BACKGROUND While most complications of cervical surgery are reversible,some,such as symptomatic postoperative spinal epidural hematoma(SEH),which generally occurs within 24 h,are associated with increased morbidity an...BACKGROUND While most complications of cervical surgery are reversible,some,such as symptomatic postoperative spinal epidural hematoma(SEH),which generally occurs within 24 h,are associated with increased morbidity and mortality.Delayed neurological dysfunction is diagnosed in cases when symptoms present>3 d postoperatively.Owing to its rarity,the risk factors for delayed neurological dysfunction are unclear.Consequently,this condition can result in irreversible neurological deficits and serious consequences.In this paper,we present a case of postoperative SEH that developed three days after hematoma evacuation.CASE SUMMARY A 68-year-old man with an American Spinal Injury Association(ASIA)grade C injury was admitted to our hospital with neck pain and tetraplegia following a fall.The C3-C7 posterior laminectomy and the lateral mass screw fixation surgery were performed on the tenth day.Postoperatively,the patient showed no changes in muscle strength or ASIA grade.The patient experienced neck pain and subcutaneous swelling on the third day postoperatively,his muscle strength decreased,and his ASIA score was grade A.Magnetic resonance imaging showed hypointense signals on T1 weighted image(T1WI)and T2WI located behind the epidural space,with spinal cord compression.Emergency surgical intervention for the hematoma was performed 12 h after onset.Although hypoproteinemia and pleural effusion did not improve in the perioperative period,the patient recovered to ASIA grade C on day 30 after surgery,and was transferred to a functional rehabilitation exercise unit.CONCLUSION This case shows that amelioration of low blood albumin and pleural effusion is an important aspect of the perioperative management of cervical surgery.Surgery to relieve the pressure on the spinal cord should be performed as soon as possible to decrease neurological disabilities.展开更多
Background: Early excision and grafting has been the preferred method of managing major burns around the world since 1970. Considering the advances in health care and the development of new antibiotics over the past 5...Background: Early excision and grafting has been the preferred method of managing major burns around the world since 1970. Considering the advances in health care and the development of new antibiotics over the past 50 years, delayed grafting as a technique for the management of burns over 15%-20% of total body surface area (TBSA) could have comparable results to that of early excision. This study aims to highlight the outcomes of practicing delayed grafting in burn patients. Methods: A case series analysis was performed of 51 patients who were admitted to the burns unit in Sultan Qaboos Hospital Salalah with over 20% TBSA between January 2014 and December 2019. The patients received prophylactic antibiotics and silver sulphadiazine dressing until the burn eschar had completely separated, followed by grafting. Results: Two patients were lost during the entire duration of the study. The mortality rate was comparable to that of early excision, while the rate of hypertrophic scarring was lower than the range reported by other studies. Conclusion: In the management of patients with over 20% TBSA, delayed grafting after complete separation of eschar is still a valid technique.展开更多
In this paper, we treat the spread of COVID-19 using a delayed stochastic SVIRS (Susceptible, Infected, Recovered, Susceptible) epidemic model with a general incidence rate and differential susceptibility. We start wi...In this paper, we treat the spread of COVID-19 using a delayed stochastic SVIRS (Susceptible, Infected, Recovered, Susceptible) epidemic model with a general incidence rate and differential susceptibility. We start with a deterministic model, then add random perturbations on the contact rate using white noise to obtain a stochastic model. We first show that the delayed stochastic differential equation that describes the model has a unique global positive solution for any positive initial value. Under the condition R<sub>0</sub> ≤ 1, we prove the almost sure asymptotic stability of the disease-free equilibrium of the model.展开更多
Objective: Vascular injuries usually present immediately after the penetration, but the delayed onset of vascular symptoms caused by vessel dissection or aneurysm after a traumatic event is extremely rare. Vertebral a...Objective: Vascular injuries usually present immediately after the penetration, but the delayed onset of vascular symptoms caused by vessel dissection or aneurysm after a traumatic event is extremely rare. Vertebral artery injury is a low-frequency but high-mortality injury. We aim to report evidence of delayed onset of vascular symptoms following penetrating trauma in the neck. Materials and Methods: A case report. Results: A 19-year-old boy was referred to our hospital and complained of a mass in the right part of his neck (right mandibular angle). He gave a history of penetrating trauma to his neck 2 months ago. The mass was expanding during these 2 months and doesn’t respond to antibiotic therapy. In the examination, 3 × 3 cm, firm, nonmobile, and without tenderness and pain mass was palpated in the second level of his neck. Doctors ordered a Doppler sonography in the hospital where a yin-yang pattern was reported. A 36 × 43 × 40 mm heterogeneous, solid, and hypodense area close to C1-C2-C3 with vascular flow was discovered in the right submandibular area after computed tomography (CT)-angiography. The patient was referred to an interventional neurologist for angiography and due to the lack of flow at the distal of the V3 segment, he decided to sacrifice this artery by two coils. Conclusion: Penetrating neck injuries are usually asymptomatic, but these injuries are often accompanied by hemorrhage, neurological symptoms, dysphagia, odynophagia, and windpipe. Penetrating lesions of the vertebral artery are rare and very difficult to diagnose. Also, these lesions are challenging for surgeons due to complex anatomy and difficult surgical exposure. So, endovascular treatment was used to treat the patient.展开更多
This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consens...This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consensus protocol is designed by using delayed and memorized state information.Under the proportional-integral consensus protocol,the consensus problem of the multi-agent system is transformed into the problem of asymptotic stability of the corresponding linear time-invariant time-delay system.Note that the location of the eigenvalues of the corresponding characteristic function of the linear time-invariant time-delay system not only determines the stability of the system,but also plays a critical role in the dynamic performance of the system.In this paper,based on recent results on the distribution of roots of quasi-polynomials,several necessary conditions for Hurwitz stability for a class of quasi-polynomials are first derived.Then allowable regions of consensus protocol parameters are estimated.Some necessary and sufficient conditions for determining effective protocol parameters are provided.The designed protocol can achieve consensus and improve the dynamic performance of the second-order multi-agent system.Moreover,the effects of delays on consensus of systems of harmonic oscillators/double integrators under proportional-integral consensus protocols are investigated.Furthermore,some results on proportional-integral consensus are derived for a class of high-order linear time-invariant multi-agent systems.展开更多
Targeted muscle reinnervation has been proposed for reconstruction of neuromuscular function in amputees.However,it is unknown whether performing delayed targeted muscle reinnervation after nerve injury will affect re...Targeted muscle reinnervation has been proposed for reconstruction of neuromuscular function in amputees.However,it is unknown whether performing delayed targeted muscle reinnervation after nerve injury will affect restoration of function.In this rat nerve injury study,the median and musculocutaneous nerves of the forelimb were transected.The proximal median nerve stump was sutured to the distal musculocutaneous nerve stump immediately and 2 and 4 weeks after surgery to reinnervate the biceps brachii.After targeted muscle reinnervation,intramuscular myoelectric signals from the biceps brachii were recorded.Signal amplitude gradually increased with time.Biceps brachii myoelectric signals and muscle fiber morphology and grooming behavior did not significantly differ among rats subjected to delayed target muscle innervation for different periods.Targeted muscle reinnervation delayed for 4 weeks can acquire the same nerve function restoration effect as that of immediate reinnervation.展开更多
BACKGROUND Endoscopic submucosal dissection(ESD)is a treatment for early gastric cancer with the advantages of small invasion,fewer complications,and a low local recurrence rate.However,there is a high risk of complic...BACKGROUND Endoscopic submucosal dissection(ESD)is a treatment for early gastric cancer with the advantages of small invasion,fewer complications,and a low local recurrence rate.However,there is a high risk of complications such as bleeding and perforation,and the operation time is also longer.ESD operation time is closely related to bleeding and perforation.AIM To investigate the influencing factors associated with ESD operation time and postoperative delayed hemorrhage to provide a reference for early planning,early identification,and prevention of complications.METHODS We conducted a retrospective study based on the clinical data of 520 patients with early gastric cancer in the Second Affiliated Hospital of Hainan Medical University from January 2019 to December 2021.The baseline data,clinical features,and endoscopic and pathological characteristics of patients were collected.The multivariate linear regression model was used to investigate the influencing factors of ESD operation time.Logistic regression analysis was carried out to evaluate the influencing factors of postoperative delayed hemorrhage.RESULTS The multivariate analysis of ESD operation time showed that the maximum lesion diameter could affect 8.815%of ESD operation time when other influencing factors remained unchanged.The operation time increased by 3.766%or 10.247%if the lesion was mixed or concave.The operation time increased by 4.417%if combined with an ulcer or scar.The operation time increased by 3.692%if combined with perforation.If infiltrated into the submucosa,it increased by 2.536%.Multivariate analysis of delayed hemorrhage after ESD showed that the maximum diameter of the lesion,lesion morphology,and ESD operation time were independent influencing factors for delayed hemorrhage after ESD.Patients with lesion≥3.0 cm(OR=3.785,95%CI:1.165-4.277),lesion morphology-concave(OR=10.985,95%CI:2.133-35.381),and ESD operation time≥60 min(OR=2.958,95%CI:1.117-3.526)were prone to delayed hemorrhage after ESD.CONCLUSION If the maximum diameter of the lesion in patients with early gastric cancer is≥3.0 cm,and the shape of the lesion is concave,or accompanied by an ulcer or scar,combined with perforation,and infiltrates into the submucosa,the ESD operation will take a longer time.When the maximum diameter of the lesion is≥3.0 cm,the shape of the lesion is concave in patients and the operation time of ESD takes longer time,the risk of delayed hemorrhage after ESD is higher.展开更多
Delayed bleeding is a major and serious adverse event of endoscopic submucosal dissection(ESD)for early-stage gastrointestinal tumors.The rate of post-ESD bleeding for gastric cancer is higher(around 5%-8%)than that f...Delayed bleeding is a major and serious adverse event of endoscopic submucosal dissection(ESD)for early-stage gastrointestinal tumors.The rate of post-ESD bleeding for gastric cancer is higher(around 5%-8%)than that for esophagus,duodenum and colon cancer(around 2%-4%).Although investigations into the risk factors for post-ESD bleeding have identified several procedure-,lesion-,physician-and patient-related factors,use of antithrombotic drugs,especially anticoagulants[direct oral anticoagulants(DOACs)and warfarin],is thought to be the biggest risk factor for post-ESD bleeding.In fact,the post-ESD bleeding rate in patients receiving DOACs is 8.7%-20.8%,which is higher than that in patients not receiving anticoagulants.However,because clinical guidelines for management of ESD in patients receiving DOACs differ among countries,it is necessary for endoscopists to identify ways to prevent post-ESD delayed bleeding in clinical practice.Given that the pharmacokinetics(e.g.,plasma DOAC level at both trough and T_(max))and pharmacodynamics(e.g.,anti-factor Xa activity)of DOACs are related to risk of major bleeding,plasma DOAC level and anti-FXa activity may be useful parameters for monitoring the anti-coagulate effect and identifying DOAC patients at higher risk of post-ESD bleeding.展开更多
BACKGROUND Tooth avulsion is one of the most severe types of dental trauma.Most avulsed teeth undergo long-term ankylosis and replacement resorption after delayed reimplantation and exhibit a poor prognosis.The aim of...BACKGROUND Tooth avulsion is one of the most severe types of dental trauma.Most avulsed teeth undergo long-term ankylosis and replacement resorption after delayed reimplantation and exhibit a poor prognosis.The aim of this work was to improve the success rate of avulsed teeth after delayed reimplantation using autologous platelet-rich fibrin(PRF).CASE SUMMARY Case 1 was a 14-year-old boy who fell and knocked out his left upper central incisor 18 h prior to his arrival at the department.The diagnoses were avulsion of tooth 21,lateral luxation of tooth 11 and alveolar fracture of teeth 11 and 21.In case 2,a 17-year-old boy fell 2 h prior to his presentation to the hospital,and his left upper lateral incisor was completely knocked out of the alveolar socket.The diagnoses included avulsion of tooth 22,complicated crown fracture of tooth 11and complicated crown-root fracture of tooth 21.The avulsed teeth were reimplanted along with autologous PRF granules and splinted using a semiflexible titanium preshaped labial arch.The root canals of the avulsed teeth were filled with calcium hydroxide paste,and root canal filling was performed 4 wk after reimplantation.The reimplanted teeth showed no symptoms of inflammatory root resorption or ankylosis at the 3-,6-,and 12-mo follow-up examinations after reimplantation with autologous PRF.In addition to the avulsed teeth,the other injured teeth were treated using corresponding conventional treatment methods.CONCLUSION These cases provide examples of the successful use of PRF to reduce pathological root resorption of the avulsed teeth,and the application of PRF may provide new healing opportunities for traditionally“hopeless”avulsed teeth.展开更多
BACKGROUND Mortality rates after pancreaticoduodenectomy(PD)have significantly decreased in specialized centers.However,postoperative morbidity,particularly delayed gastric emptying(DGE),remains the most frequent comp...BACKGROUND Mortality rates after pancreaticoduodenectomy(PD)have significantly decreased in specialized centers.However,postoperative morbidity,particularly delayed gastric emptying(DGE),remains the most frequent complication following PD.AIM To identify risk factors associated with DGE after the PD procedure.METHODS In this retrospective,cross-sectional study,clinical data were collected from 114 patients who underwent PD between January 2015 and June 2018.Demographic factors,pre-and perioperative characteristics,and surgical complications were assessed.Univariate and multivariate analyses were performed to identify risk factors for post-PD DGE.RESULTS The study included 66 males(57.9%)and 48 females(42.1%),aged 33-83 years(mean:62.5),with a male-to-female ratio of approximately 1.4:1.There were 63 cases(55.3%)of PD and 51 cases(44.7%)of pylorus-preserving pancreatoduodenectomy.Among the 114 patients who underwent PD,33(28.9%)developed postoperative DGE.Univariate analysis revealed significant differences in four of the 14 clinical indexes observed:pylorus preservation,retrocolonic anastomosis,postoperative abdominal complications,and early postoperative albumin(ALB).Logistic regression analysis further identified postoperative abdominal complic-ations[odds ratio(OR)=4.768,P=0.002],preoperative systemic diseases(OR=2.516,P=0.049),and early postoperative ALB(OR=1.195,P=0.003)as significant risk factors.CONCLUSION Postoperative severe abdominal complications,preoperative systemic diseases,and early postoperative ALB are identified as risk factors for post-PD DGE.展开更多
Residue conversion by combining catalytic hydrotreating and delayed coking has been evaluated comparatively with both processes alone.Optimal operating conditions are defined to achieve the greatest economic benefit f...Residue conversion by combining catalytic hydrotreating and delayed coking has been evaluated comparatively with both processes alone.Optimal operating conditions are defined to achieve the greatest economic benefit for upgrading an atmospheric residue from a heavy crude oil.A literature model was adapted to simulate the hydrotreating reactor,and for delayed coking,correlations reported in the literature were used.The results with both approaches were employed to calculate the techno-economic feasibility of the combined process scheme.The combination of hydrotreating and delayed coking presented an increase in light fractions of 29% and a reduction in coke production of 47.8%.Based on the calculated net benefit values,it was demonstrated that the combination of hydrotreating and delayed coking is technically and economically better than using each process alone,with highest benefit of 57.7 USD·m^(-3).展开更多
Cryptojacking is a type of resource embezzlement attack,wherein an attacker secretly executes the cryptocurrency mining program in the target host to gain profits.It has been common since 2017,and in fact,it once beca...Cryptojacking is a type of resource embezzlement attack,wherein an attacker secretly executes the cryptocurrency mining program in the target host to gain profits.It has been common since 2017,and in fact,it once became the greatest threat to network security.To better prove the attack ability the harm caused by cryptojacking,this paper proposes a new covert browser-based mining attack model named Delay-CJ,this model was deployed in a simulation environment for evaluation.Based on the general framework of cryptojacking,Delay-CJ adds hybrid evasion detection techniques and applies the delayed execution strategy specifically for video websites in the prototype implementation.The results show that the existing detection methods used for testing may become invalid as result of this model.In view of this situation,to achieve a more general and robust detection scheme,we built a cryptojacking detection system named CJDetector,which is based on cryptojacking process features.Specifically,it identifies malicious mining by monitoring CPU usage and analyzing the function call information.This system not only effectively detects the attack in our example but also has universal applicability.The recognition accuracy of CJDetector reaches 99.33%.Finally,we tested the web pages in Alexa 50K websites to investigate cryptojacking activity in the real network.We found that although cryptojacking is indeed on the decline,it remains a part of network security threats that cannot be ignored.展开更多
Objective To evaluate the utility of computed tomography perfusion(CTP)both at admission and during delayed cerebral ischemia time-window(DCITW)in the detection of delayed cerebral ischemia(DCI)and the change in CTP p...Objective To evaluate the utility of computed tomography perfusion(CTP)both at admission and during delayed cerebral ischemia time-window(DCITW)in the detection of delayed cerebral ischemia(DCI)and the change in CTP parameters from admission to DCITW following aneurysmal subarachnoid hemorrhage.Methods Eighty patients underwent CTP at admission and during DCITW.The mean and extreme values of all CTP parameters at admission and during DCITW were compared between the DCI group and non-DCI group,and comparisons were also made between admission and DCITW within each group.The qualitative color-coded perfusion maps were recorded.Finally,the relationship between CTP parameters and DCI was assessed by receiver operating characteristic(ROC)analyses.Results With the exception of cerebral blood volume(P=0.295,admission;P=0.682,DCITW),there were significant differences in the mean quantitative CTP parameters between DCI and non-DCI patients both at admission and during DCITW.In the DCI group,the extreme parameters were significantly different between admission and DCITW.The DCI group also showed a deteriorative trend in the qualitative color-coded perfusion maps.For the detection of DCI,mean transit time to the center of the impulse response function(Tmax)at admission and mean time to start(TTS)during DCITW had the largest area under curve(AUC),0.698 and 0.789,respectively.Conclusion Whole-brain CTP can predict the occurrence of DCI at admission and diagnose DCI during DCITW.The extreme quantitative parameters and qualitative color-coded perfusion maps can better reflect the perfusion changes of patients with DCI from admission to DCITW.展开更多
Aggregation-induced thermally activated delayed fluorescence(TADF)phenomena have attracted extensive attention recently.In this paper,several theoretical models including monomer,dimer,and complex are used for the exp...Aggregation-induced thermally activated delayed fluorescence(TADF)phenomena have attracted extensive attention recently.In this paper,several theoretical models including monomer,dimer,and complex are used for the explanation of the luminescent properties of(R)-5-(9H-carbazol-9-yl)-2-(1,2,3,4-tetrahydronaphthalen-1-yl)isoindoline-1,3-dione((R)-ImNCz),which was recently reported[Chemical Engineering Journal 418129167(2021)].The polarizable continuum model(PCM)and the combined quantum mechanics and molecular mechanics(QM/MM)method are adopted in simulation of the property of the molecule in the gas phase,solvated in acetonitrile and in aggregation states.It is found that large spin–orbit coupling(SOC)constants and a smaller energy gap between the first singlet excited state and the first triplet excited state(△E_(st))in prism-like single crystals(SC_(p)-form)are responsible for the TADF of(R)-lmNCz,while no TADF is found in block-like single crystals(SC_(b)-form)with a larger △E_(st).The multiple ultralong phosphorescence(UOP)peaks in the spectrum are of complex origins,and they are related not only to ImNCz but also to a minor amount of impurities(ImNBd)in the crystal prepared in the laboratory.The dimer has similar phosphorescence emission wavelengths to the(R)-lmNCz-SC_(p) monomers.The complex composed of(R)-lmNCz and(R)-lmNBd contributes to the phosphorescent emission peak at about 600 nm,and the phosphorescent emission peak at about 650 nm is generated by(R)-lmNBd.This indicates that the impurity could also contribute to emission in molecular crystals.The present calculations clarify the relationship between the molecular aggregation and the light-emitting properties of the TADF emitters and will therefore be helpful for the design of potentially more useful TADF emitters.展开更多
A viable strategy for enhancing photovoltaic performance is to comprehend the underlying quantum physical regime of charge transfer in a double quantum dots(DQD) photocell. This work explored the photovoltaic performa...A viable strategy for enhancing photovoltaic performance is to comprehend the underlying quantum physical regime of charge transfer in a double quantum dots(DQD) photocell. This work explored the photovoltaic performance dependent spatially correlated fluctuation in a DQD photocell. The effects of spatially correlated fluctuation on charge transfer and output photovoltaic efficiency were explored in a proposed DQD photocell model. The results revealed that the charge transport process and the time to peak photovoltaic efficiency were both significantly delayed by the spatially correlated fluctuation, while the anti-spatially correlated fluctuation reduced the output peak photovoltaic efficiency. Further results revealed that the delayed response could be suppressed by gap difference and tunneling coefficient within two dots. Subsequent investigation demonstrated that the delayed response was caused by the spatial correlation fluctuation slowing the generative process of noise-induced coherence, which had previously been proven to improve the quantum photovoltaic performance in quantum photocells. And the reduced photovoltaic properties were verified by the damaged noise-induced coherence owing to the anti-spatial correlation fluctuation and a hotter thermal ambient environment. The discovery of delayed response generated by the spatially correlated fluctuations will deepen the understanding of quantum features of electron transfer, as well as promises to take our understanding even further concerning quantum techniques for high efficiency DQD solar cells.展开更多
BACKGROUND For children with abdominal Henoch-Schonlein purpura presenting abdominal pain as an initial symptom and severe clinical manifestations,but without purpura appearance on the skin,the diagnosis and treatment...BACKGROUND For children with abdominal Henoch-Schonlein purpura presenting abdominal pain as an initial symptom and severe clinical manifestations,but without purpura appearance on the skin,the diagnosis and treatment are relatively difficult.This study summarized the characteristics of this group of patients by literature review and provided additional references for further refinement of glucocorticoid therapy in this vasculitis.CASE SUMMARY A 6-year-old girl presented mainly with repeated abdominal pain and had received short-term out-of-hospital treatment with hydrocortisone.On day 7 after onset,gastroscopy revealed chronic non-atrophic gastritis and erosive duodenitis without purpuric rash,and no obvious resolution of the abdominal pain was found after treatment against infection and for protection of gastric mucosa.On day 14 the inflammatory indices continued to rise and the pain was relieved after enhanced anti-infective therapy,but without complete resolution.On day 19,the patient presented with aggravated abdominal pain with purplish-red dots on the lower limbs,by which Henoch-Schonlein purpura was confirmed.After 5 d of sequential treatment with methylprednisolone and prednisone,abdominal pain disappeared and she was discharged.CONCLUSION Henoch-Schonlein purpura-related rash may appear after long-term abdominal pain,and should be distinguished from acute and chronic gastrointestinal diseases at the early stage without typical rash.For bacterial infection-induced Henoch-Schonlein purpura,glucocorticoid therapy alone without clearing the infection may not relieve symptoms.展开更多
Knee dislocations frequently involve vascular injuries that demand early diagnosis and timely intervention. Time of ischemia is pivotal in determining the outcome for the limb, delays in treatment beyond 8 hours signi...Knee dislocations frequently involve vascular injuries that demand early diagnosis and timely intervention. Time of ischemia is pivotal in determining the outcome for the limb, delays in treatment beyond 8 hours significantly increase the risk of limb loss. Unfortunately, this critical window is often missed in resource-limited settings. Here we report a 25-year-old female sustained a left knee injury after falling into a trench. She was diagnosed with an open knee dislocation accompanied by a popliteal artery injury. However, revascularization was delayed for 18 hours due to limited resources, including the unavailability of a thrombectomy catheter. Postoperatively, the patient received anticoagulation therapy with serial limb assessments and after 3 weeks the laceration healed and the limb was still viable. Knee dislocations frequently result in vascular injury (popliteal artery most common), making prompt diagnosis and intervention essential for limb preservation. In settings with limited resources, like ours, delayed presentation and transfer to specialized centers contribute to prolonged ischemic times. Nonetheless, viable limbs should be revascularized in stable patients, even with prolonged ischemia. This case highlights the importance of limb revascularization despite delay. Efforts should be made to improve prompt diagnosis, timely referral, and availability of necessary equipment for vascular repair to optimize outcomes in similar cases.展开更多
Nausea and vomiting are common adverse reactions of antitumor therapy,among which chemotherapy-induced nausea and vomiting(CINV)has been studied most intensively.Because of insufficient prevention or insufficient atte...Nausea and vomiting are common adverse reactions of antitumor therapy,among which chemotherapy-induced nausea and vomiting(CINV)has been studied most intensively.Because of insufficient prevention or insufficient attention,CINV brings a series of harms to can-cer patients and even lead to the delay or termination of antitumor therapy.Delayed CINV is often underestimated because it mostly occurs outside the hospital,and patients cannot report it immediately.In recent years,the proportion of outpatient chemotherapy and day-time chemotherapy patients in China has increased year by year.Therefore,the prevention of delayed CINV is particularly important.Currently,the challenges faced by delayed CINV include the need to deeply explore its physiological and pathological mechanisms,improve its risk assessment standards,and optimize its prevention programs.However,there is still lack of practice guidelines or consensus on delayed CINV.Therefore,the Committee of Neoplastic Supportive-Care of China Anti-Cancer Association organized multidisciplinary experts in this field to formulate this consensus based on the analysis and discussion of current evidence-based medical research in combination with clinical problems that need to be solved urgently.展开更多
Delays in sowing have significant effects on the grain yield,yield components,and grain protein concentrations of winter wheat.However,little is known about how delayed sowing affects these characteristics at differen...Delays in sowing have significant effects on the grain yield,yield components,and grain protein concentrations of winter wheat.However,little is known about how delayed sowing affects these characteristics at different positions in the wheat spikes.In this study,the effects of sowing date were investigated in a winter wheat cultivar,Shannong 30,which was sown in 2019 and 2020 on October 8(normal sowing)and October 22(late sowing)under field conditions.Delayed sowing increased the partitioning of ^(13)C-assimilates to spikes,particularly to florets at the apical section of a spike and those occupying distal positions on the same spikelet.Consequently,the increase in grain number was the greatest for the apical sections,followed by the basal and central sections.No significant differences were observed between sowing dates in the superior grain number in the basal and central sections,while the number in apical sections was significantly different.The number of inferior grains in each section also increased substantially in response to delayed sowing.The average grain weights in all sections remained unchanged under delayed sowing because there were parallel increases in grain number and ^(13)C-assimilate partitioning to grains at specific positions in the spikes.Increases in grain number m^(–2) resulted in reduced grain protein concentrations as the limited nitrogen supply was diluted into more grains.Delayed sowing caused the greatest reduction in grain protein concentration in the basal sections,followed by the central and apical sections.No significant differences in the reduction of the grain protein concentration were observed between the inferior and superior grains under delayed sowing.In conclusion,a 2-week delay in sowing improved grain yield through increased grain number per spike,which originated principally from an increased grain number in the apical sections of spikes and in distal positions on the same spikelet.However,grain protein concentrations declined in each section because of the increased grain number and reduced N uptake.展开更多
Regarding delay-induced predator-prey models, much research has been done on delayed destabilization, but whether delays are stabilizing or destabilizing is a subtle issue. In this study, we investigate predator-prey ...Regarding delay-induced predator-prey models, much research has been done on delayed destabilization, but whether delays are stabilizing or destabilizing is a subtle issue. In this study, we investigate predator-prey dynamics affected by both delays and the Allee effect. We analyze the consequences of delays in different feedback mechanisms. The existence of a Hopf bifurcation is studied, and we calculate the value of the delay that leads to the Hopf bifurcation. Furthermore, applying the normal form theory and a center manifold theorem, we consider the direction and stability of the Hopf bifurcation. Finally, we present numerical experiments that validate our theoretical analysis. Interestingly, depending on the chosen delay mechanism, we find that delays are not necessarily destabilizing. The Allee effect generally increases the stability of the equilibrium, and when the Allee effect involves a delay term, the stabilization effect is more pronounced.展开更多
文摘BACKGROUND While most complications of cervical surgery are reversible,some,such as symptomatic postoperative spinal epidural hematoma(SEH),which generally occurs within 24 h,are associated with increased morbidity and mortality.Delayed neurological dysfunction is diagnosed in cases when symptoms present>3 d postoperatively.Owing to its rarity,the risk factors for delayed neurological dysfunction are unclear.Consequently,this condition can result in irreversible neurological deficits and serious consequences.In this paper,we present a case of postoperative SEH that developed three days after hematoma evacuation.CASE SUMMARY A 68-year-old man with an American Spinal Injury Association(ASIA)grade C injury was admitted to our hospital with neck pain and tetraplegia following a fall.The C3-C7 posterior laminectomy and the lateral mass screw fixation surgery were performed on the tenth day.Postoperatively,the patient showed no changes in muscle strength or ASIA grade.The patient experienced neck pain and subcutaneous swelling on the third day postoperatively,his muscle strength decreased,and his ASIA score was grade A.Magnetic resonance imaging showed hypointense signals on T1 weighted image(T1WI)and T2WI located behind the epidural space,with spinal cord compression.Emergency surgical intervention for the hematoma was performed 12 h after onset.Although hypoproteinemia and pleural effusion did not improve in the perioperative period,the patient recovered to ASIA grade C on day 30 after surgery,and was transferred to a functional rehabilitation exercise unit.CONCLUSION This case shows that amelioration of low blood albumin and pleural effusion is an important aspect of the perioperative management of cervical surgery.Surgery to relieve the pressure on the spinal cord should be performed as soon as possible to decrease neurological disabilities.
文摘Background: Early excision and grafting has been the preferred method of managing major burns around the world since 1970. Considering the advances in health care and the development of new antibiotics over the past 50 years, delayed grafting as a technique for the management of burns over 15%-20% of total body surface area (TBSA) could have comparable results to that of early excision. This study aims to highlight the outcomes of practicing delayed grafting in burn patients. Methods: A case series analysis was performed of 51 patients who were admitted to the burns unit in Sultan Qaboos Hospital Salalah with over 20% TBSA between January 2014 and December 2019. The patients received prophylactic antibiotics and silver sulphadiazine dressing until the burn eschar had completely separated, followed by grafting. Results: Two patients were lost during the entire duration of the study. The mortality rate was comparable to that of early excision, while the rate of hypertrophic scarring was lower than the range reported by other studies. Conclusion: In the management of patients with over 20% TBSA, delayed grafting after complete separation of eschar is still a valid technique.
文摘In this paper, we treat the spread of COVID-19 using a delayed stochastic SVIRS (Susceptible, Infected, Recovered, Susceptible) epidemic model with a general incidence rate and differential susceptibility. We start with a deterministic model, then add random perturbations on the contact rate using white noise to obtain a stochastic model. We first show that the delayed stochastic differential equation that describes the model has a unique global positive solution for any positive initial value. Under the condition R<sub>0</sub> ≤ 1, we prove the almost sure asymptotic stability of the disease-free equilibrium of the model.
文摘Objective: Vascular injuries usually present immediately after the penetration, but the delayed onset of vascular symptoms caused by vessel dissection or aneurysm after a traumatic event is extremely rare. Vertebral artery injury is a low-frequency but high-mortality injury. We aim to report evidence of delayed onset of vascular symptoms following penetrating trauma in the neck. Materials and Methods: A case report. Results: A 19-year-old boy was referred to our hospital and complained of a mass in the right part of his neck (right mandibular angle). He gave a history of penetrating trauma to his neck 2 months ago. The mass was expanding during these 2 months and doesn’t respond to antibiotic therapy. In the examination, 3 × 3 cm, firm, nonmobile, and without tenderness and pain mass was palpated in the second level of his neck. Doctors ordered a Doppler sonography in the hospital where a yin-yang pattern was reported. A 36 × 43 × 40 mm heterogeneous, solid, and hypodense area close to C1-C2-C3 with vascular flow was discovered in the right submandibular area after computed tomography (CT)-angiography. The patient was referred to an interventional neurologist for angiography and due to the lack of flow at the distal of the V3 segment, he decided to sacrifice this artery by two coils. Conclusion: Penetrating neck injuries are usually asymptomatic, but these injuries are often accompanied by hemorrhage, neurological symptoms, dysphagia, odynophagia, and windpipe. Penetrating lesions of the vertebral artery are rare and very difficult to diagnose. Also, these lesions are challenging for surgeons due to complex anatomy and difficult surgical exposure. So, endovascular treatment was used to treat the patient.
基金supported in part by the National Natural Science Foundation of China (NSFC)(61703086, 61773106)the IAPI Fundamental Research Funds (2018ZCX27)
文摘This paper is concerned with consensus of a secondorder linear time-invariant multi-agent system in the situation that there exists a communication delay among the agents in the network.A proportional-integral consensus protocol is designed by using delayed and memorized state information.Under the proportional-integral consensus protocol,the consensus problem of the multi-agent system is transformed into the problem of asymptotic stability of the corresponding linear time-invariant time-delay system.Note that the location of the eigenvalues of the corresponding characteristic function of the linear time-invariant time-delay system not only determines the stability of the system,but also plays a critical role in the dynamic performance of the system.In this paper,based on recent results on the distribution of roots of quasi-polynomials,several necessary conditions for Hurwitz stability for a class of quasi-polynomials are first derived.Then allowable regions of consensus protocol parameters are estimated.Some necessary and sufficient conditions for determining effective protocol parameters are provided.The designed protocol can achieve consensus and improve the dynamic performance of the second-order multi-agent system.Moreover,the effects of delays on consensus of systems of harmonic oscillators/double integrators under proportional-integral consensus protocols are investigated.Furthermore,some results on proportional-integral consensus are derived for a class of high-order linear time-invariant multi-agent systems.
基金supported in part by the National Natural Science Foundation of China,Nos.U1913601,81927804the Key-Area Research and Development Program of Guangdong Province,No.2020B0909020004(GL)the National Natural Science Foundation of China,Nos.81960419,82260456(both to LY)。
文摘Targeted muscle reinnervation has been proposed for reconstruction of neuromuscular function in amputees.However,it is unknown whether performing delayed targeted muscle reinnervation after nerve injury will affect restoration of function.In this rat nerve injury study,the median and musculocutaneous nerves of the forelimb were transected.The proximal median nerve stump was sutured to the distal musculocutaneous nerve stump immediately and 2 and 4 weeks after surgery to reinnervate the biceps brachii.After targeted muscle reinnervation,intramuscular myoelectric signals from the biceps brachii were recorded.Signal amplitude gradually increased with time.Biceps brachii myoelectric signals and muscle fiber morphology and grooming behavior did not significantly differ among rats subjected to delayed target muscle innervation for different periods.Targeted muscle reinnervation delayed for 4 weeks can acquire the same nerve function restoration effect as that of immediate reinnervation.
文摘BACKGROUND Endoscopic submucosal dissection(ESD)is a treatment for early gastric cancer with the advantages of small invasion,fewer complications,and a low local recurrence rate.However,there is a high risk of complications such as bleeding and perforation,and the operation time is also longer.ESD operation time is closely related to bleeding and perforation.AIM To investigate the influencing factors associated with ESD operation time and postoperative delayed hemorrhage to provide a reference for early planning,early identification,and prevention of complications.METHODS We conducted a retrospective study based on the clinical data of 520 patients with early gastric cancer in the Second Affiliated Hospital of Hainan Medical University from January 2019 to December 2021.The baseline data,clinical features,and endoscopic and pathological characteristics of patients were collected.The multivariate linear regression model was used to investigate the influencing factors of ESD operation time.Logistic regression analysis was carried out to evaluate the influencing factors of postoperative delayed hemorrhage.RESULTS The multivariate analysis of ESD operation time showed that the maximum lesion diameter could affect 8.815%of ESD operation time when other influencing factors remained unchanged.The operation time increased by 3.766%or 10.247%if the lesion was mixed or concave.The operation time increased by 4.417%if combined with an ulcer or scar.The operation time increased by 3.692%if combined with perforation.If infiltrated into the submucosa,it increased by 2.536%.Multivariate analysis of delayed hemorrhage after ESD showed that the maximum diameter of the lesion,lesion morphology,and ESD operation time were independent influencing factors for delayed hemorrhage after ESD.Patients with lesion≥3.0 cm(OR=3.785,95%CI:1.165-4.277),lesion morphology-concave(OR=10.985,95%CI:2.133-35.381),and ESD operation time≥60 min(OR=2.958,95%CI:1.117-3.526)were prone to delayed hemorrhage after ESD.CONCLUSION If the maximum diameter of the lesion in patients with early gastric cancer is≥3.0 cm,and the shape of the lesion is concave,or accompanied by an ulcer or scar,combined with perforation,and infiltrates into the submucosa,the ESD operation will take a longer time.When the maximum diameter of the lesion is≥3.0 cm,the shape of the lesion is concave in patients and the operation time of ESD takes longer time,the risk of delayed hemorrhage after ESD is higher.
基金Supported by the Grant-in-Aid for Scientific Research in Japan,No.21K07949.
文摘Delayed bleeding is a major and serious adverse event of endoscopic submucosal dissection(ESD)for early-stage gastrointestinal tumors.The rate of post-ESD bleeding for gastric cancer is higher(around 5%-8%)than that for esophagus,duodenum and colon cancer(around 2%-4%).Although investigations into the risk factors for post-ESD bleeding have identified several procedure-,lesion-,physician-and patient-related factors,use of antithrombotic drugs,especially anticoagulants[direct oral anticoagulants(DOACs)and warfarin],is thought to be the biggest risk factor for post-ESD bleeding.In fact,the post-ESD bleeding rate in patients receiving DOACs is 8.7%-20.8%,which is higher than that in patients not receiving anticoagulants.However,because clinical guidelines for management of ESD in patients receiving DOACs differ among countries,it is necessary for endoscopists to identify ways to prevent post-ESD delayed bleeding in clinical practice.Given that the pharmacokinetics(e.g.,plasma DOAC level at both trough and T_(max))and pharmacodynamics(e.g.,anti-factor Xa activity)of DOACs are related to risk of major bleeding,plasma DOAC level and anti-FXa activity may be useful parameters for monitoring the anti-coagulate effect and identifying DOAC patients at higher risk of post-ESD bleeding.
基金Supported by Natural Science Foundation of China,No.31971248National Clinical Research Center for Oral Diseases Project of Military Stomatology,No.LCA202007。
文摘BACKGROUND Tooth avulsion is one of the most severe types of dental trauma.Most avulsed teeth undergo long-term ankylosis and replacement resorption after delayed reimplantation and exhibit a poor prognosis.The aim of this work was to improve the success rate of avulsed teeth after delayed reimplantation using autologous platelet-rich fibrin(PRF).CASE SUMMARY Case 1 was a 14-year-old boy who fell and knocked out his left upper central incisor 18 h prior to his arrival at the department.The diagnoses were avulsion of tooth 21,lateral luxation of tooth 11 and alveolar fracture of teeth 11 and 21.In case 2,a 17-year-old boy fell 2 h prior to his presentation to the hospital,and his left upper lateral incisor was completely knocked out of the alveolar socket.The diagnoses included avulsion of tooth 22,complicated crown fracture of tooth 11and complicated crown-root fracture of tooth 21.The avulsed teeth were reimplanted along with autologous PRF granules and splinted using a semiflexible titanium preshaped labial arch.The root canals of the avulsed teeth were filled with calcium hydroxide paste,and root canal filling was performed 4 wk after reimplantation.The reimplanted teeth showed no symptoms of inflammatory root resorption or ankylosis at the 3-,6-,and 12-mo follow-up examinations after reimplantation with autologous PRF.In addition to the avulsed teeth,the other injured teeth were treated using corresponding conventional treatment methods.CONCLUSION These cases provide examples of the successful use of PRF to reduce pathological root resorption of the avulsed teeth,and the application of PRF may provide new healing opportunities for traditionally“hopeless”avulsed teeth.
文摘BACKGROUND Mortality rates after pancreaticoduodenectomy(PD)have significantly decreased in specialized centers.However,postoperative morbidity,particularly delayed gastric emptying(DGE),remains the most frequent complication following PD.AIM To identify risk factors associated with DGE after the PD procedure.METHODS In this retrospective,cross-sectional study,clinical data were collected from 114 patients who underwent PD between January 2015 and June 2018.Demographic factors,pre-and perioperative characteristics,and surgical complications were assessed.Univariate and multivariate analyses were performed to identify risk factors for post-PD DGE.RESULTS The study included 66 males(57.9%)and 48 females(42.1%),aged 33-83 years(mean:62.5),with a male-to-female ratio of approximately 1.4:1.There were 63 cases(55.3%)of PD and 51 cases(44.7%)of pylorus-preserving pancreatoduodenectomy.Among the 114 patients who underwent PD,33(28.9%)developed postoperative DGE.Univariate analysis revealed significant differences in four of the 14 clinical indexes observed:pylorus preservation,retrocolonic anastomosis,postoperative abdominal complications,and early postoperative albumin(ALB).Logistic regression analysis further identified postoperative abdominal complic-ations[odds ratio(OR)=4.768,P=0.002],preoperative systemic diseases(OR=2.516,P=0.049),and early postoperative ALB(OR=1.195,P=0.003)as significant risk factors.CONCLUSION Postoperative severe abdominal complications,preoperative systemic diseases,and early postoperative ALB are identified as risk factors for post-PD DGE.
基金the Mexican Institute of Petroleum(IMP)for the financial support。
文摘Residue conversion by combining catalytic hydrotreating and delayed coking has been evaluated comparatively with both processes alone.Optimal operating conditions are defined to achieve the greatest economic benefit for upgrading an atmospheric residue from a heavy crude oil.A literature model was adapted to simulate the hydrotreating reactor,and for delayed coking,correlations reported in the literature were used.The results with both approaches were employed to calculate the techno-economic feasibility of the combined process scheme.The combination of hydrotreating and delayed coking presented an increase in light fractions of 29% and a reduction in coke production of 47.8%.Based on the calculated net benefit values,it was demonstrated that the combination of hydrotreating and delayed coking is technically and economically better than using each process alone,with highest benefit of 57.7 USD·m^(-3).
基金This work is partially sponsored by National Key R&D Program of China(No.2019YFB2101700)National Science Foundation of China(No.62172297,No.61902276)+1 种基金the Key Research and Development Project of Sichuan Province(No.2021YFSY0012)Tianjin Intelligent Manufacturing Special Fund Project(No.20211097,No.20201159).
文摘Cryptojacking is a type of resource embezzlement attack,wherein an attacker secretly executes the cryptocurrency mining program in the target host to gain profits.It has been common since 2017,and in fact,it once became the greatest threat to network security.To better prove the attack ability the harm caused by cryptojacking,this paper proposes a new covert browser-based mining attack model named Delay-CJ,this model was deployed in a simulation environment for evaluation.Based on the general framework of cryptojacking,Delay-CJ adds hybrid evasion detection techniques and applies the delayed execution strategy specifically for video websites in the prototype implementation.The results show that the existing detection methods used for testing may become invalid as result of this model.In view of this situation,to achieve a more general and robust detection scheme,we built a cryptojacking detection system named CJDetector,which is based on cryptojacking process features.Specifically,it identifies malicious mining by monitoring CPU usage and analyzing the function call information.This system not only effectively detects the attack in our example but also has universal applicability.The recognition accuracy of CJDetector reaches 99.33%.Finally,we tested the web pages in Alexa 50K websites to investigate cryptojacking activity in the real network.We found that although cryptojacking is indeed on the decline,it remains a part of network security threats that cannot be ignored.
基金supported by the National Natural Science Foundation of China,Research on Brain Magnetic Resonance Image Segmentation Based on Particle Computation(No.61672386).
文摘Objective To evaluate the utility of computed tomography perfusion(CTP)both at admission and during delayed cerebral ischemia time-window(DCITW)in the detection of delayed cerebral ischemia(DCI)and the change in CTP parameters from admission to DCITW following aneurysmal subarachnoid hemorrhage.Methods Eighty patients underwent CTP at admission and during DCITW.The mean and extreme values of all CTP parameters at admission and during DCITW were compared between the DCI group and non-DCI group,and comparisons were also made between admission and DCITW within each group.The qualitative color-coded perfusion maps were recorded.Finally,the relationship between CTP parameters and DCI was assessed by receiver operating characteristic(ROC)analyses.Results With the exception of cerebral blood volume(P=0.295,admission;P=0.682,DCITW),there were significant differences in the mean quantitative CTP parameters between DCI and non-DCI patients both at admission and during DCITW.In the DCI group,the extreme parameters were significantly different between admission and DCITW.The DCI group also showed a deteriorative trend in the qualitative color-coded perfusion maps.For the detection of DCI,mean transit time to the center of the impulse response function(Tmax)at admission and mean time to start(TTS)during DCITW had the largest area under curve(AUC),0.698 and 0.789,respectively.Conclusion Whole-brain CTP can predict the occurrence of DCI at admission and diagnose DCI during DCITW.The extreme quantitative parameters and qualitative color-coded perfusion maps can better reflect the perfusion changes of patients with DCI from admission to DCITW.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.11974216,11874242,21933002 and 11904210)Shandong Provincial Natural Science Foundation,China(Grant No.ZR2019MA056)+1 种基金the support of the Taishan Scholar Project of Shandong Provincethe project funded by China Postdoctoral Science Foundation(Grant No.2018M642689)。
文摘Aggregation-induced thermally activated delayed fluorescence(TADF)phenomena have attracted extensive attention recently.In this paper,several theoretical models including monomer,dimer,and complex are used for the explanation of the luminescent properties of(R)-5-(9H-carbazol-9-yl)-2-(1,2,3,4-tetrahydronaphthalen-1-yl)isoindoline-1,3-dione((R)-ImNCz),which was recently reported[Chemical Engineering Journal 418129167(2021)].The polarizable continuum model(PCM)and the combined quantum mechanics and molecular mechanics(QM/MM)method are adopted in simulation of the property of the molecule in the gas phase,solvated in acetonitrile and in aggregation states.It is found that large spin–orbit coupling(SOC)constants and a smaller energy gap between the first singlet excited state and the first triplet excited state(△E_(st))in prism-like single crystals(SC_(p)-form)are responsible for the TADF of(R)-lmNCz,while no TADF is found in block-like single crystals(SC_(b)-form)with a larger △E_(st).The multiple ultralong phosphorescence(UOP)peaks in the spectrum are of complex origins,and they are related not only to ImNCz but also to a minor amount of impurities(ImNBd)in the crystal prepared in the laboratory.The dimer has similar phosphorescence emission wavelengths to the(R)-lmNCz-SC_(p) monomers.The complex composed of(R)-lmNCz and(R)-lmNBd contributes to the phosphorescent emission peak at about 600 nm,and the phosphorescent emission peak at about 650 nm is generated by(R)-lmNBd.This indicates that the impurity could also contribute to emission in molecular crystals.The present calculations clarify the relationship between the molecular aggregation and the light-emitting properties of the TADF emitters and will therefore be helpful for the design of potentially more useful TADF emitters.
基金the National Natural Science Foundation of China (Grant Nos. 62065009 and 61565008)Yunnan Fundamental Research Projects, China (Grant No. 2016FB009)。
文摘A viable strategy for enhancing photovoltaic performance is to comprehend the underlying quantum physical regime of charge transfer in a double quantum dots(DQD) photocell. This work explored the photovoltaic performance dependent spatially correlated fluctuation in a DQD photocell. The effects of spatially correlated fluctuation on charge transfer and output photovoltaic efficiency were explored in a proposed DQD photocell model. The results revealed that the charge transport process and the time to peak photovoltaic efficiency were both significantly delayed by the spatially correlated fluctuation, while the anti-spatially correlated fluctuation reduced the output peak photovoltaic efficiency. Further results revealed that the delayed response could be suppressed by gap difference and tunneling coefficient within two dots. Subsequent investigation demonstrated that the delayed response was caused by the spatial correlation fluctuation slowing the generative process of noise-induced coherence, which had previously been proven to improve the quantum photovoltaic performance in quantum photocells. And the reduced photovoltaic properties were verified by the damaged noise-induced coherence owing to the anti-spatial correlation fluctuation and a hotter thermal ambient environment. The discovery of delayed response generated by the spatially correlated fluctuations will deepen the understanding of quantum features of electron transfer, as well as promises to take our understanding even further concerning quantum techniques for high efficiency DQD solar cells.
基金the Science and Technology Bureau of Sichuan province,No.21ZDYF1329.
文摘BACKGROUND For children with abdominal Henoch-Schonlein purpura presenting abdominal pain as an initial symptom and severe clinical manifestations,but without purpura appearance on the skin,the diagnosis and treatment are relatively difficult.This study summarized the characteristics of this group of patients by literature review and provided additional references for further refinement of glucocorticoid therapy in this vasculitis.CASE SUMMARY A 6-year-old girl presented mainly with repeated abdominal pain and had received short-term out-of-hospital treatment with hydrocortisone.On day 7 after onset,gastroscopy revealed chronic non-atrophic gastritis and erosive duodenitis without purpuric rash,and no obvious resolution of the abdominal pain was found after treatment against infection and for protection of gastric mucosa.On day 14 the inflammatory indices continued to rise and the pain was relieved after enhanced anti-infective therapy,but without complete resolution.On day 19,the patient presented with aggravated abdominal pain with purplish-red dots on the lower limbs,by which Henoch-Schonlein purpura was confirmed.After 5 d of sequential treatment with methylprednisolone and prednisone,abdominal pain disappeared and she was discharged.CONCLUSION Henoch-Schonlein purpura-related rash may appear after long-term abdominal pain,and should be distinguished from acute and chronic gastrointestinal diseases at the early stage without typical rash.For bacterial infection-induced Henoch-Schonlein purpura,glucocorticoid therapy alone without clearing the infection may not relieve symptoms.
文摘Knee dislocations frequently involve vascular injuries that demand early diagnosis and timely intervention. Time of ischemia is pivotal in determining the outcome for the limb, delays in treatment beyond 8 hours significantly increase the risk of limb loss. Unfortunately, this critical window is often missed in resource-limited settings. Here we report a 25-year-old female sustained a left knee injury after falling into a trench. She was diagnosed with an open knee dislocation accompanied by a popliteal artery injury. However, revascularization was delayed for 18 hours due to limited resources, including the unavailability of a thrombectomy catheter. Postoperatively, the patient received anticoagulation therapy with serial limb assessments and after 3 weeks the laceration healed and the limb was still viable. Knee dislocations frequently result in vascular injury (popliteal artery most common), making prompt diagnosis and intervention essential for limb preservation. In settings with limited resources, like ours, delayed presentation and transfer to specialized centers contribute to prolonged ischemic times. Nonetheless, viable limbs should be revascularized in stable patients, even with prolonged ischemia. This case highlights the importance of limb revascularization despite delay. Efforts should be made to improve prompt diagnosis, timely referral, and availability of necessary equipment for vascular repair to optimize outcomes in similar cases.
文摘Nausea and vomiting are common adverse reactions of antitumor therapy,among which chemotherapy-induced nausea and vomiting(CINV)has been studied most intensively.Because of insufficient prevention or insufficient attention,CINV brings a series of harms to can-cer patients and even lead to the delay or termination of antitumor therapy.Delayed CINV is often underestimated because it mostly occurs outside the hospital,and patients cannot report it immediately.In recent years,the proportion of outpatient chemotherapy and day-time chemotherapy patients in China has increased year by year.Therefore,the prevention of delayed CINV is particularly important.Currently,the challenges faced by delayed CINV include the need to deeply explore its physiological and pathological mechanisms,improve its risk assessment standards,and optimize its prevention programs.However,there is still lack of practice guidelines or consensus on delayed CINV.Therefore,the Committee of Neoplastic Supportive-Care of China Anti-Cancer Association organized multidisciplinary experts in this field to formulate this consensus based on the analysis and discussion of current evidence-based medical research in combination with clinical problems that need to be solved urgently.
基金Financial support was received from the National Key Research and Development Program of China(2016YFD0300403 and 2017YFD0201705)。
文摘Delays in sowing have significant effects on the grain yield,yield components,and grain protein concentrations of winter wheat.However,little is known about how delayed sowing affects these characteristics at different positions in the wheat spikes.In this study,the effects of sowing date were investigated in a winter wheat cultivar,Shannong 30,which was sown in 2019 and 2020 on October 8(normal sowing)and October 22(late sowing)under field conditions.Delayed sowing increased the partitioning of ^(13)C-assimilates to spikes,particularly to florets at the apical section of a spike and those occupying distal positions on the same spikelet.Consequently,the increase in grain number was the greatest for the apical sections,followed by the basal and central sections.No significant differences were observed between sowing dates in the superior grain number in the basal and central sections,while the number in apical sections was significantly different.The number of inferior grains in each section also increased substantially in response to delayed sowing.The average grain weights in all sections remained unchanged under delayed sowing because there were parallel increases in grain number and ^(13)C-assimilate partitioning to grains at specific positions in the spikes.Increases in grain number m^(–2) resulted in reduced grain protein concentrations as the limited nitrogen supply was diluted into more grains.Delayed sowing caused the greatest reduction in grain protein concentration in the basal sections,followed by the central and apical sections.No significant differences in the reduction of the grain protein concentration were observed between the inferior and superior grains under delayed sowing.In conclusion,a 2-week delay in sowing improved grain yield through increased grain number per spike,which originated principally from an increased grain number in the apical sections of spikes and in distal positions on the same spikelet.However,grain protein concentrations declined in each section because of the increased grain number and reduced N uptake.
基金supported by the Gansu Science and Technology Fund (20JR5RA512)the Research Fund for Humanities and Social Sciences of the Ministry of Education (20XJAZH006)+2 种基金the Fundamental Research Funds for the Central Universities (31920220066)the Gansu Provincial Education Department:Outstanding Postgraduate Innovation Star Project (2023CXZX-196)the Leading Talents Project of State Ethnic Affairs Commission of China and the Innovation Team of Intelligent Computing and Dynamical System Analysis and Application of Northwest Minzu University。
文摘Regarding delay-induced predator-prey models, much research has been done on delayed destabilization, but whether delays are stabilizing or destabilizing is a subtle issue. In this study, we investigate predator-prey dynamics affected by both delays and the Allee effect. We analyze the consequences of delays in different feedback mechanisms. The existence of a Hopf bifurcation is studied, and we calculate the value of the delay that leads to the Hopf bifurcation. Furthermore, applying the normal form theory and a center manifold theorem, we consider the direction and stability of the Hopf bifurcation. Finally, we present numerical experiments that validate our theoretical analysis. Interestingly, depending on the chosen delay mechanism, we find that delays are not necessarily destabilizing. The Allee effect generally increases the stability of the equilibrium, and when the Allee effect involves a delay term, the stabilization effect is more pronounced.
