Background:Soil acidifcationn caused by anthropogenic activities may aft soil biochemical cydling,bidiversity,productivity,and multiple eosystem-related functions in drylands.However,to date,such information is lackin...Background:Soil acidifcationn caused by anthropogenic activities may aft soil biochemical cydling,bidiversity,productivity,and multiple eosystem-related functions in drylands.However,to date,such information is lacking to support this hypothesis.Methods Based on a transect survey of 78 naturally assembled shrub communities,we caloulated acid deposition flux in Northwest China and evaluated its likely ecological ffets by testing three altemnative hypotheses,namely:.nidche complementarity,mass ratio,and vegetation quantity hypotheses Rao's quadratic entopy and community-weighted mean traits were employed to represent the complementary aspect of niche complementarity and mass ratio effects,respectively.Resulbs:We observed that in the past four decades,the concentrations of exchangeable base cations in soil in Northwest China have decreased significantly to the extent of having faced the risk of depletion,whereas changes in the calium carbonate content and pH of soil were not significant.Adid deposition primani ly increased the aboweground biomass and shrub density in shrublands but had no sigmificant effect on shrub richness and ecasystem multifunctionality(EMF),indicating that acid deposition had positive but weak ecological effects on dryland ecosystems.Community wd ghted mean of functional traits(representing the mass ratio hypothesis)correlated negatively with EMF,whereas both Rao's quadratic entropy(representing the niche complementarity hypothesis)and aboveground biomass(representing the vegetation quantity hypothesis)correlated positively but insignifcantly with EMF.These biodiversity-EMF relationships highlight the fragility and instability of drylands relative to forest ecasystems.Concuions:The findings from this study serve as important reference points to understand the ris of soil acidification in arid regions and its impacts on biodiversity-EMF relationships.展开更多
With the boom of the communication systems on some independent platforms(such as satellites,space stations,airplanes,and vessels),co-site interference is becoming prominent.The adaptive interference cancellation metho...With the boom of the communication systems on some independent platforms(such as satellites,space stations,airplanes,and vessels),co-site interference is becoming prominent.The adaptive interference cancellation method has been adopted to solve the co-site interference problem.But the broadband interference cancellation performance of traditional Adaptive Co-site Interference Cancellation System(ACICS)with large delay mismatching and antenna sway is relatively poor.This study put forward an Adaptive Co-site Broadband Interference Cancellation System With Two Auxiliary Channels(ACBICS-2A).The system model was established,and the steady state weights and Interference Cancellation Ratio(ICR)were deduced by solving a time-varying differential equation.The relationship of ICR,system gain,modulation factor,interference signal bandwidth and delay mismatching degree was acquired through an in-depth analysis.Compared with traditional adaptive interference cancellation system,the proposed ACBICS-2A can improve broadband interference cancellation ability remarkably with large delay mismatching and antenna sway for the effect of auxiliary channel.The maximum improved ICR is more than 25 dB.Finally,the theoretical and simulation results were verified by experiments.展开更多
Proximity effects between superconductors and ferromagnets(SC/FM)hold paramount importance in comprehending the spin competition transpiring at their interfaces.This competition arises from the interplay between Coope...Proximity effects between superconductors and ferromagnets(SC/FM)hold paramount importance in comprehending the spin competition transpiring at their interfaces.This competition arises from the interplay between Cooper pairs and ferromagnetic exchange interactions.The proximity effects between transition metal nitrides(TMNs)are scarcely investigated due to the formidable challenges of fabricating high-quality SC/FM interfaces.We fabricated heterostructures comprising SC titanium nitride(TiN)and FM iron nitride(Fe_(3)N)with precise chemical compositions and atomically well-defined interfaces.The magnetoresistance of Fe_(3)N/TiN heterostructures shows a distinct magnetic anisotropy and strongly depends on the external perturbations.Moreover,the superconducting transition temperatureT_(C) and critical field of TiN experience notable suppression when proximity to Fe_(3)N.We observe the intriguing competition of interfacial spin orientations near𝑇T_(C)(∼1.25 K).These findings not only add a new materials system for investigating the interplay between superconductor and ferromagnets,but also potentially provide a building block for future research endeavors and applications in the realms of superconducting spintronic devices.展开更多
Based on the conventional observation data and NCEP/NCAR reanalysis data,the circulation situation,influencing systems and causes of the heavy rain during September 20-21,2010 in Ulanqab City were analyzed from the ev...Based on the conventional observation data and NCEP/NCAR reanalysis data,the circulation situation,influencing systems and causes of the heavy rain during September 20-21,2010 in Ulanqab City were analyzed from the evolution process of weather circulation situation and the changes of various physical quantity fields.The results show that there was an obvious frontal zone between 45-52°N,which brought strong cold air.The transport of warm and humid air outside the subtropical high and typhoon was the main water vapor source of the strong precipitation,and the southwest jet at 700 hPa transported abundant water vapor.There was a broad inverted trough to the south of 45°N,with a central value of 1000.0 hPa.Ulanqab City was on the top of the inverted trough,stable and less moved,which was conducive to the occurrence of systematic heavy precipitation.The rainstorm was a strong precipitation process caused by the intersection of cold air brought by the southward movement of the upper frontal zone and warm and humid air outside the subtropical high.After the precipitation,the invasion of strong cold air brought frost and cold wave weather to Ulanqab City.展开更多
Based on the data of national observation stations of CMISS system,artificial encrypted observation data of snow depth,ERA5 reanalysis data,the snowfall process in Ulanqab City from March 17 to 19,2022 was analyzed.It...Based on the data of national observation stations of CMISS system,artificial encrypted observation data of snow depth,ERA5 reanalysis data,the snowfall process in Ulanqab City from March 17 to 19,2022 was analyzed.It is found that the influencing system of the snowfall process was upper-air trough combined with ground inverted trough.Snowfall was not proportional to snow depth,and the relationship between the maximum snow depth and total snowfall varied in different value intervals.A large intensity of snowfall was a necessary condition for the formation of abundant accumulated snow when ground temperature was higher than 0℃.After the formation of accumulated snow,ground temperature changed less,and it was easy to produce accumulated snow as ground temperature was lower.The lower the temperature,the more conducive to the generation of accumulated snow.展开更多
Unmanned Aerial Vehicle(UAV)communication is a promising technology that provides swift and flexible ondemand wireless connectivity for devices without infrastructure support.With recent developments in UAVs,spectrum ...Unmanned Aerial Vehicle(UAV)communication is a promising technology that provides swift and flexible ondemand wireless connectivity for devices without infrastructure support.With recent developments in UAVs,spectrum and energy efficient green UAV communication has become crucial.To deal with this issue,Spectrum Sharing Policy(SSP)is introduced to support green UAV communication.Spectrum sensing in SSP must be carefully formulated to control interference to the primary users and ground communications.In this paper,we propose spectrum sensing for opportunistic spectrum access in green UAV communication to improve the spectrum utilization efficiency.Different from most existing works,we focus on the problem of spectrum sensing of randomly arriving primary signals in the presence of non-Gaussian noise/interference.We propose a novel and improved p-norm-based spectrum sensing scheme to improve the spectrum utilization efficiency in green UAV communication.Firstly,we construct the p-norm decision statistic based on the assumption that the random arrivals of signals follow a Poisson process.Then,we analyze and derive the approximate analytical expressions of the false-alarm and detection probabilities by utilizing the central limit theorem.Simulation results illustrate the validity and superiority of the proposed scheme when the primary signals are corrupted by additive non-Gaussian noise and arrive randomly during spectrum sensing in the green UAV communication.展开更多
针对飞鸟和旋翼无人机目标识别的迫切需求,开展微多普勒测量实验研究.首先对飞鸟翅膀扑翼运动、无人机目标主体运动和旋翼转动进行建模分析与参数化表征,从雷达动目标回波中提取多普勒频移信息;然后利用短时傅里叶变换转换为时频图,对...针对飞鸟和旋翼无人机目标识别的迫切需求,开展微多普勒测量实验研究.首先对飞鸟翅膀扑翼运动、无人机目标主体运动和旋翼转动进行建模分析与参数化表征,从雷达动目标回波中提取多普勒频移信息;然后利用短时傅里叶变换转换为时频图,对目标微多普勒特征进行精细化描述,并从雷达参数、目标类型、观测条件等多个角度重点分析了微动特征的影响因素;最后利用K波段线性调频连续波雷达开展飞鸟和两款典型旋翼无人机("御MAVIC Air 2"和"悟Inspire 2")微动测量实验,对微动参数进行估计,验证了理论模型的正确性.实测数据分析表明:目标旋翼叶片长度越大、转速越高,微多普勒频率越大;叶片数目增多导致微动特征重叠;雷达观测角度、调制周期以及时频分析的时间窗长均会对微动特性产生重要影响.展开更多
High spectrum efficiency(SE)requirement and massive connections are the main challenges for the fifth generation(5G)and beyond 5G(B5G)wireless networks,especially for the case when Internet of Things(IoT)devices are l...High spectrum efficiency(SE)requirement and massive connections are the main challenges for the fifth generation(5G)and beyond 5G(B5G)wireless networks,especially for the case when Internet of Things(IoT)devices are located in a disaster area.Non-orthogonal multiple access(NOMA)-based unmanned aerial vehicle(UAV)-aided network is emerging as a promising technique to overcome the above challenges.In this paper,an emergency communications framework of NOMA-based UAV-aided networks is established,where the disasters scenarios can be divided into three broad categories that have named emergency areas,wide areas and dense areas.First,a UAV-enabled uplink NOMA system is established to gather information from IoT devices in emergency areas.Then,a joint UAV deployment and resource allocation scheme for a multi-UAV enabled NOMA system is developed to extend the UAV coverage for IoT devices in wide areas.Furthermore,a UAV equipped with an antenna array has been considered to provide wireless service for multiple devices that are densely distributed in disaster areas.Simulation results are provided to validate the effectiveness of the above three schemes.Finally,potential research directions and challenges are also highlighted and discussed.展开更多
AIM To compare the efficacy,improved quality of life,and prognosis in patients undergoing either subtotal colonic bypass with antiperistaltic cecoproctostomy(SCBAC) or subtotal colonic bypass plus colostomy with antip...AIM To compare the efficacy,improved quality of life,and prognosis in patients undergoing either subtotal colonic bypass with antiperistaltic cecoproctostomy(SCBAC) or subtotal colonic bypass plus colostomy with antiperistaltic cecoproctostomy(SCBCAC) for the treatment of slow transit constipation.METHODS Between October 2010 and October 2014,aged patients with slow transit constipation who were hospitalized and underwent laparoscopic surgery in our institute weredivided into two groups: the bypass group,15 patients underwent SCBAC,and the bypass plus colostomy group,14 patients underwent SCBCAC. The following preoperative and postoperative clinical data were collected: gender,age,body mass index,operative time,first flatus time,length of hospital stay,bowel movements(BMs),Wexner fecal incontinence scale,Wexner constipation scale(WCS),gastrointestinal quality of life index(GIQLI),numerical rating scale for pain intensity(NRS),abdominal bloating score(ABS),and ClavienDindo classification of surgical complications(CD) before surgery and at 3,6,12,and 24 mo after surgery.RESULTS All patients successfully underwent laparoscopic surgery without open surgery conversion or surgeryrelated death. The operative time and blood loss were significantly less in the bypass group than in the bypass plus colostomy group(P = 0.007). No significant differences were observed in first flatus time,length of hospital stay,or complications with CD > 1 between the two groups. No patients had fecal incontinence after surgery. At 3,6,and 12 mo after surgery,the number of BMs was significantly less in the bypass plus colostomy group than in the bypass group. The parameters at 3,6,12,and 24 mo after surgery in both groups significantly improved compared with the preoperative conditions(P < 0.05),except NRS at 3,6 mo after surgery in both groups,ABS at 12,24 mo after surgery and NRS at 12,24 mo after surgery in the bypass group. WCS,GIQLI,NRS,and ABS significantly improved in the bypass plus colostomy group compared with the bypass group at 3,6,12,and 24 mo after surgery(P < 0.05) except WCS,NRS at 3,6 mo after surgery and ABS at 3 mo after surgery. At 1 year after surgery,a barium enema examination showed that the emptying time was significantly better in the bypass plus colostomy group than in the bypass group(P = 0.007).CONCLUSION Laparoscopic SCBCAC is an effective and safe procedure for the treatment of slow transit constipation in an aged population and can significantly improve the prognosis. Its clinical efficacy is more favorable compared with that of SCBAC. Laparoscopic SCBCAC is a better procedure for the treatment of slow transit constipation in an aged population.展开更多
Background Hyperprolactinemia is a common adverse reaction in patients with schizophrenia who take antipsychotic drugs;it often leads to treatment noncompliance in patients and has an adverse effect on their prognosis...Background Hyperprolactinemia is a common adverse reaction in patients with schizophrenia who take antipsychotic drugs;it often leads to treatment noncompliance in patients and has an adverse effect on their prognosis.Aims This study aimed to explore the risk factors of elevated prolactin(PRL)caused by risperidone(RIS)and olanzapine(OLZ)and the relationship between PRL and fasting plasma glucose and lipids.Methods Patients with schizophrenia were divided into two groups:264 patients who were taking RIS and 175 patients who were taking OLZ.These two groups were further divided according to serum PRL levels:an elevated PRL group(>30ng/mL)and a normal PRL group(PRL<30ng/mL).The demographics,medication dosage,fasting plasma glucose,total cholesterol and triglycerides were compared in the two groups.Logistic regression analysis was performed to explore the risk factors of elevated PRL levels.Results Compared with the OLZ group,the RIS group had a greater number of patients with elevated PRL(155/264 vs 58/175).Either the RIS or the OLZ group,the proportion of elevated PRL was greater in female patients(RIS:x^2=6.76,p=0.009;OLZ:x^2=12.98,p<0.001)and with higher doses of the related drugs(RIS:U=-3.73,p<0.001;OLZ:U=-2.31,p=0.021).In patients taking RIS,the elevated PRL subgroup took the drug for a longer period(U=-2.76,p=0.006)and had lower triglyceride levels(U=2.76,p=0.006).In patients taking OLZ,the elevated PRL subgroup had lower fasting plasma glucose levels(U=2.29,p=0.022).Logistic regression analysis showed that gender,dose and fasting glucose levels were significantly associated with elevated PRL levels(RIS:p=0.001,OLZ:p<0.001;RIS:p<0.001;OLZ:p=0.003;RIS:p=0.020,OLZ:p=0.001,respectively).Conclusion Compared with OLZ,RIS had a greater effect on PRL in patients with schizophrenia,and in patients with schizophrenia taking RIS or OLZ,gender and dose were significantly correlated with the PRL value.Moreover,the plasma glucose level of the group with elevated PRL was lower than that of the group with normal PRL.The results also showed that high serum PRL may be associated with a favourable glucose metabolic profile in patients with schizophrenia taking RIS or OLZ.Further studies are warranted to confirm this association.展开更多
BACKGROUND Internal rectal prolapse(IRP)is one of the most common causes of obstructive constipation.The incidence of IRP in women is approximately three times that in men.IRP is mainly treated by surgery,which can be...BACKGROUND Internal rectal prolapse(IRP)is one of the most common causes of obstructive constipation.The incidence of IRP in women is approximately three times that in men.IRP is mainly treated by surgery,which can be divided into two categories:Abdominal procedures and perineal procedures.This study offers a better procedure for the treatment of IRP.AIM To compare the clinical efficacy of laparoscopic integral pelvic floor/ligament repair(IPFLR)combined with a procedure for prolapse and hemorrhoids(PPH)and the laparoscopic IPFLR alone in the treatment of IRP in women.METHODS This study collected the clinical data of 130 female patients with IRP who underwent surgery from January 2012 to October 2014.The patients were divided into groups A and B.Group A had 63 patients who underwent laparoscopic IPFLR alone,and group B had 67 patients who underwent the laparoscopic IPFLR combined with PPH.The degree of internal rectal prolapse(DIRP),Wexner constipation scale(WCS)score,Wexner incontinence scale(WIS)score,and Gastrointestinal Quality of Life Index(GIQLI)score were compared between groups and within groups before surgery and 6 mo and 2 years after surgery.RESULTS All laparoscopic surgeries were successful.The general information,number of bowel movements before surgery,DIRP,GIQLI score,WIS score,and WCS score before surgery were not significantly different between the two groups(all P>0.05).The WCS score,WIS score,GIQLI score,and DIRP in each group 6 mo,and 2 years after surgery were significantly better than before surgery(P<0.001).In group A,the DIRP and WCS score gradually improved from 6 mo to 2 years after surgery(P<0.001),and the GIQLI score progressively improved from 6 mo to 2 years after surgery(P<0.05).In group B,the DIRP,WCS score and WIS score significantly improved from 6 mo to 2 years after surgery(P<0.05),and the GIQLI score 2 years after surgery was significantly higher than that 6 mo after surgery(P<0.05).The WCS score,WIS score,GIQLI score,and DIRP of group B were significantly better than those of group A 6 mo and 2 years after surgery(all P<0.001,Bonferroni)except DIRP at 2 years after surgery.There was a significant difference in the recurrence rate of IRP between the two groups 6 mo after surgery(P=0.011).There was no significant difference in postoperative grade I-III complications between the two groups(P=0.822).CONCLUSION Integral theory–guided laparoscopic IPFLR combined with PPH has a higher cure rate and a better clinical efficacy than laparoscopic IPFLR alone.展开更多
Objective: Hypoxia is a significant feature of solid tumors, including pancreatic ductal adenocarcinoma(PDAC). It is associated with tumor invasion, metastasis, and drug resistance. However, the spatial distribution o...Objective: Hypoxia is a significant feature of solid tumors, including pancreatic ductal adenocarcinoma(PDAC). It is associated with tumor invasion, metastasis, and drug resistance. However, the spatial distribution of hypoxia-related heterogeneity in PDAC remains unclear.Methods: Spatial transcriptomics(STs), a new technique, was used to investigate the ST features of engrafted human PDAC in the ischemic hind limbs of nude mice. Transcriptomes from ST spots in the hypoxic tumor and the control were clustered using differentially-expressed genes. These data were compared to determine the spatial organization of hypoxia-induced heterogeneity in PDAC. Clinical relevance was validated using the Tumor Cancer Genome Atlas and KM-plotter databases. The CMAP website was used to identify molecules that may serve as therapeutic targets for PDAC.Results: ST showed that the tumor cell subgroups decreased to 7 subgroups in the hypoxia group, compared to 9 subgroups in the control group. Different subgroups showed positional characteristics and different gene signatures. Subgroup 6 located at the invasive front showed a higher proliferative ability under hypoxia. Subgroup 6 had active functions including cell proliferation, invasion, and response to stress. Expressions of hypoxia-related genes, LDHA, TPI1, and ENO1, induced changes. CMAP analysis indicated that ADZ-6482, a PI3 K inhibitor, was targeted by the invasive subgroup in hypoxic tumors.Conclusions: This study is the first to describe hypoxic microenvironment-induced spatial transcriptome changes in PDAC, and to identify potential treatment targets for PDAC. These data will provide the basis for further investigations of the prognoses and treatments of hypoxic tumors.展开更多
6G IoT networks aim for providing significantly higher data rates and extremely lower latency.However,due to the increasingly scarce spectrum bands and ever-growing massive number IoT devices(IoDs)deployed,6G IoT netw...6G IoT networks aim for providing significantly higher data rates and extremely lower latency.However,due to the increasingly scarce spectrum bands and ever-growing massive number IoT devices(IoDs)deployed,6G IoT networks face two critical challenges,i.e.,energy limitation and severe signal attenuation.Simultaneous wireless information and power transfer(SWIPT)and cooperative relaying provide effective ways to address these two challenges.In this paper,we investigate the energy self-sustainability(ESS)of 6G IoT network and propose an OFDM based bidirectional multi-relay SWIPT strategy for 6G IoT networks.In the proposed strategy,the transmission process is equally divided into two phases.Specifically,in phase1 two source nodes transmit their signals to relay nodes which will then use different subcarrier sets to decode information and harvest energy,respectively.In phase2 relay nodes forward signals to corresponding destination nodes with the harvested energy.We maximize the weighted sum transmission rate by optimizing subcarriers and power allocation.Our proposed strategy achieves larger weighted sum transmission rate comparing with the benchmark scheme.展开更多
BACKGROUND Sternal tumors are difficult to diagnose, and usually need to be differentiated from other diseases such as tuberculosis, osteosarcoma, intrathoracic thyroid and thymoma. The sternum is a rare site of Hodg...BACKGROUND Sternal tumors are difficult to diagnose, and usually need to be differentiated from other diseases such as tuberculosis, osteosarcoma, intrathoracic thyroid and thymoma. The sternum is a rare site of Hodgkin’s lymphoma, which is often misdiagnosed as tuberculosis on routine histopathology.CASE SUMMARY We reported a 47-year-old female patient with chest pain in the upper sternum for 1 mo. Chest computed tomography found a mass in the upper sternum.Pathology and immunohistochemistry of the biopsy confirmed the diagnosis of typical Hodgkin’s lymphoma(mixed cellularity subtype). Patient was diagnosed with primary sternal Hodgkin’s lymphoma and administered 6 cycles of adriamycin, bleomycin, vinblastine, and dacarbazine chemotherapy. Patient had no tumor recurrence and progression at a follow-up visit 2 years later.CONCLUSION This study highlights the rarity of primary sternal Hodgkin’s lymphoma and the challenges of its diagnosis. A Pub Med and Web of Science search revealed 10 reported cases of sternal involvement in Hodgkin’s lymphoma.展开更多
Passive detection of moving target is an important part of intelligent surveillance. Satellite has the potential to play a key role in many applications of space-air-ground integrated networks(SAGIN). In this paper, w...Passive detection of moving target is an important part of intelligent surveillance. Satellite has the potential to play a key role in many applications of space-air-ground integrated networks(SAGIN). In this paper, we propose a novel intelligent passive detection method for aerial target based on reservoir computing networks. Specifically, delayed feedback networks are utilized to refine the direct signals from the satellite in the reference channels. In addition, the satellite direct wave interference in the monitoring channels adopts adaptive interference suppression using the minimum mean square error filter. Furthermore, we employ decoupling echo state networks to predict the clutter interference in the monitoring channels and construct the detection statistics accordingly. Finally, a multilayer perceptron is adopted to detect the echo signal after interference suppression. Extensive simulations is conducted to evaluate the performance of our proposed method. Results show that the detection probability is almost 100% when the signal-to-interference ratio of echo signal is-36 dB, which demonstrates that our proposed method achieves efficient passive detection for aerial targets in typical SAGIN scenarios.展开更多
Packed-bed reactors(PBRs)hold great promise for environmental applications,but a deeper understanding of the behavior of plasma discharge within PBRs is required.To this end,a partial-discharge alternative equivalent ...Packed-bed reactors(PBRs)hold great promise for environmental applications,but a deeper understanding of the behavior of plasma discharge within PBRs is required.To this end,a partial-discharge alternative equivalent circuit for PBRs was established in this work.Dielectric particles(glass beads or glass sand)were used to place focus on the effects of the particle size and shape on the partial discharge behavior of the oxygen PBRs.Some electrical characterizations were explored(e.g.the effective dielectric capacitance,partial discharge coefficient,and corrected burning voltage)that may differ from long-standing interpretations.The findings indicate that the suppressive effect of surface discharge on filament discharge is stronger with the decrease of the particle size.For partial discharge,the effective dielectric capacitance is always less than the dielectric capacitance.The corrected burning voltage and partial discharge tendency increase with the decrease of the particle size.As compared to an empty reactor,the average electric field in the PBR was found to be improved by 3–4 times,and the ozone energy efficiency and production were promoted by more than 20%and 15%,respectively.The plasma processing capacity can therefore be improved by choosing a relatively large size or a complex,irregularly-shaped packing material that is suitable for the discharge gap.展开更多
基金financially supported by the third xinjiang scientific expedition program (grant no.2022xjkk0901)the Strategic Priority Research Program of Chinese Academy of Sciences (No.XDA2006030102)the National Natural Sciences Foundation of China(No.42171068 and No.42330503)。
文摘Background:Soil acidifcationn caused by anthropogenic activities may aft soil biochemical cydling,bidiversity,productivity,and multiple eosystem-related functions in drylands.However,to date,such information is lacking to support this hypothesis.Methods Based on a transect survey of 78 naturally assembled shrub communities,we caloulated acid deposition flux in Northwest China and evaluated its likely ecological ffets by testing three altemnative hypotheses,namely:.nidche complementarity,mass ratio,and vegetation quantity hypotheses Rao's quadratic entopy and community-weighted mean traits were employed to represent the complementary aspect of niche complementarity and mass ratio effects,respectively.Resulbs:We observed that in the past four decades,the concentrations of exchangeable base cations in soil in Northwest China have decreased significantly to the extent of having faced the risk of depletion,whereas changes in the calium carbonate content and pH of soil were not significant.Adid deposition primani ly increased the aboweground biomass and shrub density in shrublands but had no sigmificant effect on shrub richness and ecasystem multifunctionality(EMF),indicating that acid deposition had positive but weak ecological effects on dryland ecosystems.Community wd ghted mean of functional traits(representing the mass ratio hypothesis)correlated negatively with EMF,whereas both Rao's quadratic entropy(representing the niche complementarity hypothesis)and aboveground biomass(representing the vegetation quantity hypothesis)correlated positively but insignifcantly with EMF.These biodiversity-EMF relationships highlight the fragility and instability of drylands relative to forest ecasystems.Concuions:The findings from this study serve as important reference points to understand the ris of soil acidification in arid regions and its impacts on biodiversity-EMF relationships.
基金supported by the National Natural Science Foundation of China[Grant No.61771187]the Natural Science Foundation of Hubei Province[Grant No.2016CFB396]+1 种基金the Hubei Provincial Technology Innovation Special Major Project[Grant No.2019AAA018]the Major Project of Hubei Collaborative Innovation Center for High-efficiency Utilization of Solar Energy[HBSKFZD2015002].
文摘With the boom of the communication systems on some independent platforms(such as satellites,space stations,airplanes,and vessels),co-site interference is becoming prominent.The adaptive interference cancellation method has been adopted to solve the co-site interference problem.But the broadband interference cancellation performance of traditional Adaptive Co-site Interference Cancellation System(ACICS)with large delay mismatching and antenna sway is relatively poor.This study put forward an Adaptive Co-site Broadband Interference Cancellation System With Two Auxiliary Channels(ACBICS-2A).The system model was established,and the steady state weights and Interference Cancellation Ratio(ICR)were deduced by solving a time-varying differential equation.The relationship of ICR,system gain,modulation factor,interference signal bandwidth and delay mismatching degree was acquired through an in-depth analysis.Compared with traditional adaptive interference cancellation system,the proposed ACBICS-2A can improve broadband interference cancellation ability remarkably with large delay mismatching and antenna sway for the effect of auxiliary channel.The maximum improved ICR is more than 25 dB.Finally,the theoretical and simulation results were verified by experiments.
基金supported by the National Key Research and Development Program of China(Grant Nos.2020YFA0309100 and 2019YFA0308500)the National Natural Science Foundation of China(Grant Nos.U22A20263,52250308,and 11974390)+3 种基金the CAS Project for Young Scientists in Basic Research(Grant No.YSBR-084)(E.J.G.)Special Research Assistant(Q.J.),the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(Grant No.XDB33030200)(K.J.)the China Postdoctoral Science Foundation(Grant No.2022M723353)the Guangdong-Hong Kong-Macao Joint Laboratory for Neutron Scattering Science and Technology(Grant No.HTCSNS-DG-CD-0080/2021).
文摘Proximity effects between superconductors and ferromagnets(SC/FM)hold paramount importance in comprehending the spin competition transpiring at their interfaces.This competition arises from the interplay between Cooper pairs and ferromagnetic exchange interactions.The proximity effects between transition metal nitrides(TMNs)are scarcely investigated due to the formidable challenges of fabricating high-quality SC/FM interfaces.We fabricated heterostructures comprising SC titanium nitride(TiN)and FM iron nitride(Fe_(3)N)with precise chemical compositions and atomically well-defined interfaces.The magnetoresistance of Fe_(3)N/TiN heterostructures shows a distinct magnetic anisotropy and strongly depends on the external perturbations.Moreover,the superconducting transition temperatureT_(C) and critical field of TiN experience notable suppression when proximity to Fe_(3)N.We observe the intriguing competition of interfacial spin orientations near𝑇T_(C)(∼1.25 K).These findings not only add a new materials system for investigating the interplay between superconductor and ferromagnets,but also potentially provide a building block for future research endeavors and applications in the realms of superconducting spintronic devices.
文摘Based on the conventional observation data and NCEP/NCAR reanalysis data,the circulation situation,influencing systems and causes of the heavy rain during September 20-21,2010 in Ulanqab City were analyzed from the evolution process of weather circulation situation and the changes of various physical quantity fields.The results show that there was an obvious frontal zone between 45-52°N,which brought strong cold air.The transport of warm and humid air outside the subtropical high and typhoon was the main water vapor source of the strong precipitation,and the southwest jet at 700 hPa transported abundant water vapor.There was a broad inverted trough to the south of 45°N,with a central value of 1000.0 hPa.Ulanqab City was on the top of the inverted trough,stable and less moved,which was conducive to the occurrence of systematic heavy precipitation.The rainstorm was a strong precipitation process caused by the intersection of cold air brought by the southward movement of the upper frontal zone and warm and humid air outside the subtropical high.After the precipitation,the invasion of strong cold air brought frost and cold wave weather to Ulanqab City.
文摘Based on the data of national observation stations of CMISS system,artificial encrypted observation data of snow depth,ERA5 reanalysis data,the snowfall process in Ulanqab City from March 17 to 19,2022 was analyzed.It is found that the influencing system of the snowfall process was upper-air trough combined with ground inverted trough.Snowfall was not proportional to snow depth,and the relationship between the maximum snow depth and total snowfall varied in different value intervals.A large intensity of snowfall was a necessary condition for the formation of abundant accumulated snow when ground temperature was higher than 0℃.After the formation of accumulated snow,ground temperature changed less,and it was easy to produce accumulated snow as ground temperature was lower.The lower the temperature,the more conducive to the generation of accumulated snow.
基金supported by the International Research Center of Big Data for Sustainable Development Goals [grant number CBAS2022GSP01]the National Natural Science Foundation of China [grant numbers 42276203 and 42030406]+1 种基金the Natural Science Foundation of Shandong Province [grant number ZR2021MD001]the Laoshan Laboratory [grant number LSKJ202204302].
基金supported by the National Natural Science Foundation of China under Grant 62071364 and 62231027China Postdoctoral Science Foundation under Grant 2022M722504+1 种基金in part by the Key Research and Development Program of Shaanxi under Grant 2023-YBGY-249in part by the Fundamental Research Funds for the Central Universities under Grant XJSJ23090 and KYFZ23001.
文摘Unmanned Aerial Vehicle(UAV)communication is a promising technology that provides swift and flexible ondemand wireless connectivity for devices without infrastructure support.With recent developments in UAVs,spectrum and energy efficient green UAV communication has become crucial.To deal with this issue,Spectrum Sharing Policy(SSP)is introduced to support green UAV communication.Spectrum sensing in SSP must be carefully formulated to control interference to the primary users and ground communications.In this paper,we propose spectrum sensing for opportunistic spectrum access in green UAV communication to improve the spectrum utilization efficiency.Different from most existing works,we focus on the problem of spectrum sensing of randomly arriving primary signals in the presence of non-Gaussian noise/interference.We propose a novel and improved p-norm-based spectrum sensing scheme to improve the spectrum utilization efficiency in green UAV communication.Firstly,we construct the p-norm decision statistic based on the assumption that the random arrivals of signals follow a Poisson process.Then,we analyze and derive the approximate analytical expressions of the false-alarm and detection probabilities by utilizing the central limit theorem.Simulation results illustrate the validity and superiority of the proposed scheme when the primary signals are corrupted by additive non-Gaussian noise and arrive randomly during spectrum sensing in the green UAV communication.
文摘针对飞鸟和旋翼无人机目标识别的迫切需求,开展微多普勒测量实验研究.首先对飞鸟翅膀扑翼运动、无人机目标主体运动和旋翼转动进行建模分析与参数化表征,从雷达动目标回波中提取多普勒频移信息;然后利用短时傅里叶变换转换为时频图,对目标微多普勒特征进行精细化描述,并从雷达参数、目标类型、观测条件等多个角度重点分析了微动特征的影响因素;最后利用K波段线性调频连续波雷达开展飞鸟和两款典型旋翼无人机("御MAVIC Air 2"和"悟Inspire 2")微动测量实验,对微动参数进行估计,验证了理论模型的正确性.实测数据分析表明:目标旋翼叶片长度越大、转速越高,微多普勒频率越大;叶片数目增多导致微动特征重叠;雷达观测角度、调制周期以及时频分析的时间窗长均会对微动特性产生重要影响.
文摘High spectrum efficiency(SE)requirement and massive connections are the main challenges for the fifth generation(5G)and beyond 5G(B5G)wireless networks,especially for the case when Internet of Things(IoT)devices are located in a disaster area.Non-orthogonal multiple access(NOMA)-based unmanned aerial vehicle(UAV)-aided network is emerging as a promising technique to overcome the above challenges.In this paper,an emergency communications framework of NOMA-based UAV-aided networks is established,where the disasters scenarios can be divided into three broad categories that have named emergency areas,wide areas and dense areas.First,a UAV-enabled uplink NOMA system is established to gather information from IoT devices in emergency areas.Then,a joint UAV deployment and resource allocation scheme for a multi-UAV enabled NOMA system is developed to extend the UAV coverage for IoT devices in wide areas.Furthermore,a UAV equipped with an antenna array has been considered to provide wireless service for multiple devices that are densely distributed in disaster areas.Simulation results are provided to validate the effectiveness of the above three schemes.Finally,potential research directions and challenges are also highlighted and discussed.
基金the Medical Science and technology Project of Henan Province,No.2011030031
文摘AIM To compare the efficacy,improved quality of life,and prognosis in patients undergoing either subtotal colonic bypass with antiperistaltic cecoproctostomy(SCBAC) or subtotal colonic bypass plus colostomy with antiperistaltic cecoproctostomy(SCBCAC) for the treatment of slow transit constipation.METHODS Between October 2010 and October 2014,aged patients with slow transit constipation who were hospitalized and underwent laparoscopic surgery in our institute weredivided into two groups: the bypass group,15 patients underwent SCBAC,and the bypass plus colostomy group,14 patients underwent SCBCAC. The following preoperative and postoperative clinical data were collected: gender,age,body mass index,operative time,first flatus time,length of hospital stay,bowel movements(BMs),Wexner fecal incontinence scale,Wexner constipation scale(WCS),gastrointestinal quality of life index(GIQLI),numerical rating scale for pain intensity(NRS),abdominal bloating score(ABS),and ClavienDindo classification of surgical complications(CD) before surgery and at 3,6,12,and 24 mo after surgery.RESULTS All patients successfully underwent laparoscopic surgery without open surgery conversion or surgeryrelated death. The operative time and blood loss were significantly less in the bypass group than in the bypass plus colostomy group(P = 0.007). No significant differences were observed in first flatus time,length of hospital stay,or complications with CD > 1 between the two groups. No patients had fecal incontinence after surgery. At 3,6,and 12 mo after surgery,the number of BMs was significantly less in the bypass plus colostomy group than in the bypass group. The parameters at 3,6,12,and 24 mo after surgery in both groups significantly improved compared with the preoperative conditions(P < 0.05),except NRS at 3,6 mo after surgery in both groups,ABS at 12,24 mo after surgery and NRS at 12,24 mo after surgery in the bypass group. WCS,GIQLI,NRS,and ABS significantly improved in the bypass plus colostomy group compared with the bypass group at 3,6,12,and 24 mo after surgery(P < 0.05) except WCS,NRS at 3,6 mo after surgery and ABS at 3 mo after surgery. At 1 year after surgery,a barium enema examination showed that the emptying time was significantly better in the bypass plus colostomy group than in the bypass group(P = 0.007).CONCLUSION Laparoscopic SCBCAC is an effective and safe procedure for the treatment of slow transit constipation in an aged population and can significantly improve the prognosis. Its clinical efficacy is more favorable compared with that of SCBAC. Laparoscopic SCBCAC is a better procedure for the treatment of slow transit constipation in an aged population.
基金This study was supported from the Shanghai clinical research center for mental health(19MC1911100)the Clinical tech-platform for evaluation of new drug in Psychiatry(CPEP)(2018ZX09734-005)+2 种基金the Strategic Priority Research Program of Chinese Academy of Sciences(XDA12040105)the Clinical Research Center,Shanghai Jiao Tong University School of Medicine(DLY201620)the Analysis on the change of prolactin in antipsychotics and its related factors(CRC2018DSJ01-2)。
文摘Background Hyperprolactinemia is a common adverse reaction in patients with schizophrenia who take antipsychotic drugs;it often leads to treatment noncompliance in patients and has an adverse effect on their prognosis.Aims This study aimed to explore the risk factors of elevated prolactin(PRL)caused by risperidone(RIS)and olanzapine(OLZ)and the relationship between PRL and fasting plasma glucose and lipids.Methods Patients with schizophrenia were divided into two groups:264 patients who were taking RIS and 175 patients who were taking OLZ.These two groups were further divided according to serum PRL levels:an elevated PRL group(>30ng/mL)and a normal PRL group(PRL<30ng/mL).The demographics,medication dosage,fasting plasma glucose,total cholesterol and triglycerides were compared in the two groups.Logistic regression analysis was performed to explore the risk factors of elevated PRL levels.Results Compared with the OLZ group,the RIS group had a greater number of patients with elevated PRL(155/264 vs 58/175).Either the RIS or the OLZ group,the proportion of elevated PRL was greater in female patients(RIS:x^2=6.76,p=0.009;OLZ:x^2=12.98,p<0.001)and with higher doses of the related drugs(RIS:U=-3.73,p<0.001;OLZ:U=-2.31,p=0.021).In patients taking RIS,the elevated PRL subgroup took the drug for a longer period(U=-2.76,p=0.006)and had lower triglyceride levels(U=2.76,p=0.006).In patients taking OLZ,the elevated PRL subgroup had lower fasting plasma glucose levels(U=2.29,p=0.022).Logistic regression analysis showed that gender,dose and fasting glucose levels were significantly associated with elevated PRL levels(RIS:p=0.001,OLZ:p<0.001;RIS:p<0.001;OLZ:p=0.003;RIS:p=0.020,OLZ:p=0.001,respectively).Conclusion Compared with OLZ,RIS had a greater effect on PRL in patients with schizophrenia,and in patients with schizophrenia taking RIS or OLZ,gender and dose were significantly correlated with the PRL value.Moreover,the plasma glucose level of the group with elevated PRL was lower than that of the group with normal PRL.The results also showed that high serum PRL may be associated with a favourable glucose metabolic profile in patients with schizophrenia taking RIS or OLZ.Further studies are warranted to confirm this association.
基金Supported by Medical Science and Technology Project of Henan Province,China,No.2011030031.
文摘BACKGROUND Internal rectal prolapse(IRP)is one of the most common causes of obstructive constipation.The incidence of IRP in women is approximately three times that in men.IRP is mainly treated by surgery,which can be divided into two categories:Abdominal procedures and perineal procedures.This study offers a better procedure for the treatment of IRP.AIM To compare the clinical efficacy of laparoscopic integral pelvic floor/ligament repair(IPFLR)combined with a procedure for prolapse and hemorrhoids(PPH)and the laparoscopic IPFLR alone in the treatment of IRP in women.METHODS This study collected the clinical data of 130 female patients with IRP who underwent surgery from January 2012 to October 2014.The patients were divided into groups A and B.Group A had 63 patients who underwent laparoscopic IPFLR alone,and group B had 67 patients who underwent the laparoscopic IPFLR combined with PPH.The degree of internal rectal prolapse(DIRP),Wexner constipation scale(WCS)score,Wexner incontinence scale(WIS)score,and Gastrointestinal Quality of Life Index(GIQLI)score were compared between groups and within groups before surgery and 6 mo and 2 years after surgery.RESULTS All laparoscopic surgeries were successful.The general information,number of bowel movements before surgery,DIRP,GIQLI score,WIS score,and WCS score before surgery were not significantly different between the two groups(all P>0.05).The WCS score,WIS score,GIQLI score,and DIRP in each group 6 mo,and 2 years after surgery were significantly better than before surgery(P<0.001).In group A,the DIRP and WCS score gradually improved from 6 mo to 2 years after surgery(P<0.001),and the GIQLI score progressively improved from 6 mo to 2 years after surgery(P<0.05).In group B,the DIRP,WCS score and WIS score significantly improved from 6 mo to 2 years after surgery(P<0.05),and the GIQLI score 2 years after surgery was significantly higher than that 6 mo after surgery(P<0.05).The WCS score,WIS score,GIQLI score,and DIRP of group B were significantly better than those of group A 6 mo and 2 years after surgery(all P<0.001,Bonferroni)except DIRP at 2 years after surgery.There was a significant difference in the recurrence rate of IRP between the two groups 6 mo after surgery(P=0.011).There was no significant difference in postoperative grade I-III complications between the two groups(P=0.822).CONCLUSION Integral theory–guided laparoscopic IPFLR combined with PPH has a higher cure rate and a better clinical efficacy than laparoscopic IPFLR alone.
基金supported by grants from the National Natural Science Key Foundation of China (Grants Nos. 82030092 and 81230050)。
文摘Objective: Hypoxia is a significant feature of solid tumors, including pancreatic ductal adenocarcinoma(PDAC). It is associated with tumor invasion, metastasis, and drug resistance. However, the spatial distribution of hypoxia-related heterogeneity in PDAC remains unclear.Methods: Spatial transcriptomics(STs), a new technique, was used to investigate the ST features of engrafted human PDAC in the ischemic hind limbs of nude mice. Transcriptomes from ST spots in the hypoxic tumor and the control were clustered using differentially-expressed genes. These data were compared to determine the spatial organization of hypoxia-induced heterogeneity in PDAC. Clinical relevance was validated using the Tumor Cancer Genome Atlas and KM-plotter databases. The CMAP website was used to identify molecules that may serve as therapeutic targets for PDAC.Results: ST showed that the tumor cell subgroups decreased to 7 subgroups in the hypoxia group, compared to 9 subgroups in the control group. Different subgroups showed positional characteristics and different gene signatures. Subgroup 6 located at the invasive front showed a higher proliferative ability under hypoxia. Subgroup 6 had active functions including cell proliferation, invasion, and response to stress. Expressions of hypoxia-related genes, LDHA, TPI1, and ENO1, induced changes. CMAP analysis indicated that ADZ-6482, a PI3 K inhibitor, was targeted by the invasive subgroup in hypoxic tumors.Conclusions: This study is the first to describe hypoxic microenvironment-induced spatial transcriptome changes in PDAC, and to identify potential treatment targets for PDAC. These data will provide the basis for further investigations of the prognoses and treatments of hypoxic tumors.
基金This work was supported by China National Science Foundation under Grant No.61871348by University Key Laboratory of Advanced Wireless Communications of Guangdong Province,by the Project funded by China Postdoctoral Science Foundation under Grant 2019T120531+1 种基金by the Science and Technology Development Fund,Macao,China under Grant 0162/2019/A3by the Fundamental Research Funds for the Provincial Universities of Zhejiang under Grant RFA2019001.
文摘6G IoT networks aim for providing significantly higher data rates and extremely lower latency.However,due to the increasingly scarce spectrum bands and ever-growing massive number IoT devices(IoDs)deployed,6G IoT networks face two critical challenges,i.e.,energy limitation and severe signal attenuation.Simultaneous wireless information and power transfer(SWIPT)and cooperative relaying provide effective ways to address these two challenges.In this paper,we investigate the energy self-sustainability(ESS)of 6G IoT network and propose an OFDM based bidirectional multi-relay SWIPT strategy for 6G IoT networks.In the proposed strategy,the transmission process is equally divided into two phases.Specifically,in phase1 two source nodes transmit their signals to relay nodes which will then use different subcarrier sets to decode information and harvest energy,respectively.In phase2 relay nodes forward signals to corresponding destination nodes with the harvested energy.We maximize the weighted sum transmission rate by optimizing subcarriers and power allocation.Our proposed strategy achieves larger weighted sum transmission rate comparing with the benchmark scheme.
文摘BACKGROUND Sternal tumors are difficult to diagnose, and usually need to be differentiated from other diseases such as tuberculosis, osteosarcoma, intrathoracic thyroid and thymoma. The sternum is a rare site of Hodgkin’s lymphoma, which is often misdiagnosed as tuberculosis on routine histopathology.CASE SUMMARY We reported a 47-year-old female patient with chest pain in the upper sternum for 1 mo. Chest computed tomography found a mass in the upper sternum.Pathology and immunohistochemistry of the biopsy confirmed the diagnosis of typical Hodgkin’s lymphoma(mixed cellularity subtype). Patient was diagnosed with primary sternal Hodgkin’s lymphoma and administered 6 cycles of adriamycin, bleomycin, vinblastine, and dacarbazine chemotherapy. Patient had no tumor recurrence and progression at a follow-up visit 2 years later.CONCLUSION This study highlights the rarity of primary sternal Hodgkin’s lymphoma and the challenges of its diagnosis. A Pub Med and Web of Science search revealed 10 reported cases of sternal involvement in Hodgkin’s lymphoma.
基金supported by the National Natural Science Foundation of China under Grant 62071364in part by the Aeronautical Science Foundation of China under Grant 2020Z073081001+2 种基金in part by the Fundamental Research Funds for the Central Universities under Grant JB210104in part by the Shaanxi Provincial Key Research and Development Program under Grant 2019GY-043in part by the 111 Project under Grant B08038。
文摘Passive detection of moving target is an important part of intelligent surveillance. Satellite has the potential to play a key role in many applications of space-air-ground integrated networks(SAGIN). In this paper, we propose a novel intelligent passive detection method for aerial target based on reservoir computing networks. Specifically, delayed feedback networks are utilized to refine the direct signals from the satellite in the reference channels. In addition, the satellite direct wave interference in the monitoring channels adopts adaptive interference suppression using the minimum mean square error filter. Furthermore, we employ decoupling echo state networks to predict the clutter interference in the monitoring channels and construct the detection statistics accordingly. Finally, a multilayer perceptron is adopted to detect the echo signal after interference suppression. Extensive simulations is conducted to evaluate the performance of our proposed method. Results show that the detection probability is almost 100% when the signal-to-interference ratio of echo signal is-36 dB, which demonstrates that our proposed method achieves efficient passive detection for aerial targets in typical SAGIN scenarios.
基金supported by National Natural Science Foundation of China(Nos.51806085,51676089)China Postdoctoral Science Foundation(2018M642175)the Double Innovation Talents of Jiangsu Province and Jiangsu University Youth Talent Cultivation Program Funded Project
文摘Packed-bed reactors(PBRs)hold great promise for environmental applications,but a deeper understanding of the behavior of plasma discharge within PBRs is required.To this end,a partial-discharge alternative equivalent circuit for PBRs was established in this work.Dielectric particles(glass beads or glass sand)were used to place focus on the effects of the particle size and shape on the partial discharge behavior of the oxygen PBRs.Some electrical characterizations were explored(e.g.the effective dielectric capacitance,partial discharge coefficient,and corrected burning voltage)that may differ from long-standing interpretations.The findings indicate that the suppressive effect of surface discharge on filament discharge is stronger with the decrease of the particle size.For partial discharge,the effective dielectric capacitance is always less than the dielectric capacitance.The corrected burning voltage and partial discharge tendency increase with the decrease of the particle size.As compared to an empty reactor,the average electric field in the PBR was found to be improved by 3–4 times,and the ozone energy efficiency and production were promoted by more than 20%and 15%,respectively.The plasma processing capacity can therefore be improved by choosing a relatively large size or a complex,irregularly-shaped packing material that is suitable for the discharge gap.
