Two-dimensional time-resolved particle image velocimetry(TR-PIV)and stereographic particle image velocimetry(SPIV)techniques were used to investigate the effect of leading-edge tubercles on the flow over low-aspect-ra...Two-dimensional time-resolved particle image velocimetry(TR-PIV)and stereographic particle image velocimetry(SPIV)techniques were used to investigate the effect of leading-edge tubercles on the flow over low-aspect-ratio wing models.The angle of attack is fixed at 10°,and the Reynolds number based on chord length is 5.8×10^(3).It is shown that the leading-edge tubercles can effectively mitigate flow separation in the model and also reduce the contribution of wake vortex to the fluctuating energy of flow.Counter-rotating vortex pairs(CVPs)initiated from the peak of leading-edge tubercles can promote nearby momentum exchange,enhance mixing of the flow and increase the energy contained in the boundary layer,which results in resisting the larger adverse pressure gradient.Therefore,it is concluded that CVPs play an important role in mitigating the flow separation for wings with leading-edge tubercles.展开更多
BACKGROUND Several previous studies have reported an unusual root formation in which a fractured apical fragment of an immature root continued to develop independent of the main root after trauma to an immature tooth....BACKGROUND Several previous studies have reported an unusual root formation in which a fractured apical fragment of an immature root continued to develop independent of the main root after trauma to an immature tooth.To date,there have been only rare reports of the continuing apical formation of the fractured root associated with dens evaginatus(DE).This paper presents a case of a separated root tip formation associated with a fractured tubercle of DE.CASE SUMMARY An 11-year-old boy was referred for gingival sinus on the buccal side of the right mandibular second premolar(tooth#45).Clinically,tooth#45 was free of caries,but there was a sign of a fractured tubercle of DE on the occlusal surface.Radiography showed that the root canal of tooth#45 was widely radiolucent.A separated root apex was found apically under the main root and was nearly completely formed with an apical orifice at the apical tip.Tooth#45 was diagnosed as tubular fracture of DE with chronic apical periodontitis.A revascularization technique was recommended to treat the tooth.At 3-mo and 1-yr follow-up,the patient remained asymptomatic.Periapical radiography revealed that the separated root tip distally drifted with closure of the apex.However,the root length and thickness of the main root did not increased.CONCLUSION Clinicians should be aware that even if tubercle of DE is fractured in an immature tooth,the root tip may be separated from the main root and completely formed.展开更多
BACKGROUND Tibial tubercle osteotomy(TTO) is a well-established surgical technique to deal with a stiff knee in revision total knee arthroplasty(RTKA). However, several reports have described potential osteotomy-relat...BACKGROUND Tibial tubercle osteotomy(TTO) is a well-established surgical technique to deal with a stiff knee in revision total knee arthroplasty(RTKA). However, several reports have described potential osteotomy-related complications such as nonunion, tibial tubercle migration and fragmentation, and metalware related pain.AIM To evaluate the literature and estimate the efficiency of TTO in RTKA in terms of osteotomy union, knee mobility and complications.METHODS MEDLINE, Scopus, and the Cochrane Central Register of Controlled Trials were investigated for completed studies until February 2020. The principle outcome of the study was the incidence of union of the osteotomy. Secondary outcomes were the knee range of motion as well as the TTO-related and overall procedure complication rate.RESULTS Fifteen clinical studies with a total of 593 TTOs were included. The TTO union rate was 98.1%. Proximal migration and anterior knee pain were the most common TTO-related complications accounting for 6.9% and 6.4% of all cases,respectively. However, only 2.2% of cases suffering from anterior knee pain needed hardware removal. Knee flexion was improved from 82.9° preoperatively to 100.1° postoperatively and total knee range of motion was increased from 73.4° before surgery to 97° after surgery. Stiffness requiring manipulation under anesthesia was recorded in 4.6% of cases. No major complications were reported.CONCLUSION The current systematic review supports the use of TTO in RTKA, as it is associated with high union rate, significant improvement in knee motion and low osteotomy-related complication risk that rarely leads to secondary tibial tubercle procedures.展开更多
To distinguish the taxonomy of Yihuang wild rice found in Yihuang County, Jiangxi Province, China in 1999, the botanical characteristics of Yihuang wild rice were retrieved by genus, and species; at the same time, the...To distinguish the taxonomy of Yihuang wild rice found in Yihuang County, Jiangxi Province, China in 1999, the botanical characteristics of Yihuang wild rice were retrieved by genus, and species; at the same time, the tubercle characters on lemma in Yihuang wild rice, O. rufipogon, 0. officinalis, 0. meyeriana, and O. granulata, were also observed by scanning electron microscopy. The retrieval result by genus showed that Yihuang wild rice is Leersia Soland. Ex Swartz., not Oryza L., Hygroryza Nees and Chikusichloa Koidz. The retrieval result by species showed that Yihuang wild rice is L. sayanuka Ohwi, not L. hexandra Swartz., L. japonica (Makino) Honda and L. oryzoides (L.) Swartz. The results of the SEM observation on tubercles on lemma showed that the tubercle characters on lemma of Yihuang wild rice belongs to "inlaid- silica-peak" type, which is different from the three types of wild rice existing in China, O. rufipogon, O. officinalis, O. Meyeriana, and also O. granulata, but is similar to L. tisseranti, thereby gives a proof of the above retrieval results. It could be concluded that Yihuang wild rice does not belong to Oryza L., but to Leersia sayanuka Ohwi of Leersia Soland. Ex Swartz.展开更多
BACKGROUND Identification of the morphology of the genial tubercles (GTs) is valuable for different dental applications. The morphological pattern of the GTs is still controversial, and therefore, the study of its mor...BACKGROUND Identification of the morphology of the genial tubercles (GTs) is valuable for different dental applications. The morphological pattern of the GTs is still controversial, and therefore, the study of its morphology using cone beam computed tomography (CBCT) plays a valuable role in resolving the controversy. AIM To assess the morphological pattern, dimensions and position of the GTs using CBCT among a selected Saudi population. METHODS CBCT records of 155 Saudi subjects (49 female and 106 male) were used to assess the pattern and size of the GTs and to determine the distance from the apices of the lower central incisors to the superior border of the incisors (I-SGT) and the distance from the inferior border of the GTs to the menton (IGT-M). RESULTS The results of this study showed that the most common morphological pattern was of two superior GTs and a rough impression below them (36.8%), followed by two superior GTs and a median ridge representing fused inferior GTs below them (22.6%) and a single median eminence or projection (20%). The classically described pattern, of two superior and two inferior GTs placed one above the other, was found in only 14.2% of cases, while 6.4% of the studied cases had no GTs. The mean width and height were 6.23 ± 1.93 mm and 6.67 ± 3.04 mm, respectively, while the mean I-SGT and IGT-M measurements were 8.26 ± 2.7 mm and 8.13 ± 3.07 mm, respectively. CONCLUSION The GTs are a controversial anatomical landmark with wide variation in their morphological pattern. The most common pattern among the studied Saudi sample was of two superior GTs and a rough impression below them, and there were no significant differences between males and females.展开更多
Dear Editor,I am Bing Li from the Department of Ophthalmology,Peking Union Medical College Hospital in Beijing, China,and I write to present a case report of choroidal and ciliary body tubercles.Ocular tuberculosis (T...Dear Editor,I am Bing Li from the Department of Ophthalmology,Peking Union Medical College Hospital in Beijing, China,and I write to present a case report of choroidal and ciliary body tubercles.Ocular tuberculosis (TB) is an extrapulmonary tuberculous condition with variable manifestations[1].展开更多
Corner stall receives noticeable attention in the aeroengine field as an important phenomenon in highly-load compressors.Non-uniform leading-edge tubercles,as an effective method to delay stall,are introduced into the...Corner stall receives noticeable attention in the aeroengine field as an important phenomenon in highly-load compressors.Non-uniform leading-edge tubercles,as an effective method to delay stall,are introduced into the compressor.In this paper,the shape of leading-edge tubercles was controlled by a third-order Fourier function.To judge corner stall,a more precise stall indicator for compressor cascade with flow control methods was defined.Besides,the total kinetic energy of the secondary flow at large incidence was adopted as a parameter for stall evaluation to save computing resources.The results of multiobjective optimization reveal that the loss coefficient exhibited negligible variation at design incidence,while the total kinetic energy of secondary flow showed a significant reduction at large incidence,resulting in a substantial increase in stall incidence.In the optimal profiling cases,the stall incidencewas delayed from 7.9°to 11.6°.The major purpose of the research is to provide proper design guidelines for nonuniformleading-edge tubercles and uncover the flow controlmechanisms of leading-edge profiling.Hence,the geometric features that meet different optimization objectives were extracted through geometric analysis near the Pareto Front and through Self-OrganizingMap(SOM)dataminingmethods in the optimization database.Besides,flow field analysis reveals the flow control mechanism of leading-edge tubercles.The convex-concave-convex structure at the 0%-70%blade height region can form two branches of leading-edge vortex pairs that are opposite in the rotation direction to the passage vortex.The two branches of leading-edge vortex pairs mixed with the leading-edge separation vortex to form two stronger mixed vortices,which can effectively suppress the development of passage vortex and delay stall incidence.展开更多
The influences of leading-edge tubercle amplitude on airfoil flow field have been analyzed at high angle of attack.The accuracy of a large eddy simulation(LES)research is validated through quantitative comparisons wit...The influences of leading-edge tubercle amplitude on airfoil flow field have been analyzed at high angle of attack.The accuracy of a large eddy simulation(LES)research is validated through quantitative comparisons with corresponding experimental results.Then,a proper orthogonal decomposition(POD)analysis has been carried out based on the unsteady flow field and the fluid mechanisms of corresponding POD modes have been identified.Consequently,the influences of leading-edge tubercle amplitude have been uncovered.Since the streamwise vorticity is larger than that of small amplitude cases,the momentum transfer process at peaks is more obvious for large amplitude,leading to delayed flow separation.Both amplitude and wavelength play important roles in the generation of laminar separation bubble(LSB)at troughs.Moreover,the Karman vortex shedding process takes place at specific trough sections as pairs of periodic spatial structures exist in the dominant POD modes.The destruction of Karman vortex shedding process is strengthened along with the increase of amplitude.展开更多
BACKGROUND De-Quervain’s tenosynovitis is a disorder arising from the compression and irritation of the first dorsal extensor compartment of the wrist.Patients who fail conservative treatment modalities are candidate...BACKGROUND De-Quervain’s tenosynovitis is a disorder arising from the compression and irritation of the first dorsal extensor compartment of the wrist.Patients who fail conservative treatment modalities are candidates for surgical release.However,risks with surgery include damage to the superficial radial nerve and an incomplete release due to inadequate dissection.Currently,there is a paucity of literature demonstrating the exact anatomic location of the first dorsal extensor compartment in reference to surface anatomy.Thus,this cadaveric study was performed to determine the exact location of the first extensor compartment and to devise a reliable surgical incision to prevent complications.AIM To describe the location of the first dorsal compartment in relation to bony surface landmarks to create replicable surgical incisions.METHODS Six cadaveric forearms,including four left and two right forearm specimens were dissected.Dissections were performed by a single fellowship trained upper extremity orthopaedic surgeon.Distance of the first dorsal compartment from landmarks such as Lister’s tubercle,the wrist crease,and the radial styloid were calculated.Other variables studied included the presence of the superficial radial nerve overlying the first dorsal compartment,additional compartment subsheaths,number of abductor pollicis longus(APL)tendon slips,and the presence of a pseudo-retinaculum.RESULTS Distance from the radial most aspect of the wrist crease to the extensor retinaculum was 5.14 mm±0.80 mm.The distance from Lister’s tubercle to the distal aspect of the extensor retinaculum was 13.37 mm±2.94 mm.Lister’s tubercle to the start of the first dorsal compartment was 18.43 mm±2.01 mm.The radial styloid to the initial aspect of the extensor retinaculum measured 2.98 mm±0.99 mm.The retinaculum length longitudinally on average was 26.82 mm±3.34 mm.Four cadaveric forearms had separate extensor pollicis brevis compartments.The average number of APL tendon slips was three.A pseudo-retinaculum was present in four cadavers.Two cadavers had a superficial radial nerve that crossed over the first dorsal compartment and retinaculum proximally(7.03 mm and 13.36 mm).CONCLUSION An incision that measures 3 mm proximal from the radial styloid,2 cm radial from Lister’s tubercle,and 5 mm proximal from the radial wrist crease will safely place surgeons at the first dorsal compartment.展开更多
Recent research proves that wings with leading-edge tubercles have the ability to perform efficiently in post-stall region over the conventional straight wing. Moreover, the conventional straight wing outperforms the ...Recent research proves that wings with leading-edge tubercles have the ability to perform efficiently in post-stall region over the conventional straight wing. Moreover, the conventional straight wing outperforms the tubercled wing at a pre-stall region which is quintessential. Even though tubercled wing offers great performance enhancement, because of the complexity of the flow, the trough region of the tubercled wing is more prone to flow separation. Henceforth, the present paper aims at surface blowing – an active flow control technique over the tubercled wing to enhance the aerodynamic efficiency by positively influencing its lift characteristics without causing any additional drag penalty. Flow parameters like blowing velocity ratios and the location of blowing were chosen to find the optimised configuration keeping the amplitude and frequency of the leading-edge tubercles constant as 0.12 c and 0.25 c respectively. Numerical investigations were carried out over the baseline tubercled wing and tubercled wing with surface blowing at various blowing jet velocity ratios 0.5, 1 and 2 over four different chordwise locations ranging from 0.3 c to 0.8 c.The results confirm that blowing at various x/c with different blowing velocity ratios performs better than the conventional tubercled wing. Comparatively, blowing velocity ratio 2 at 0.3 c shows peak performance of about 28% enhancement in the lift characteristics relative to the baseline model. Particularly, in the pre-stall region, 25–50% increase in aerodynamic efficiency is evident over the tubercled wing with surface blowing compared with the baseline case. Additionally,attempts were made to delineate the physical significance of the flow separation mechanism due to blowing by visualizing the streamline pattern.展开更多
The brains of ray-finned fishes form a morphocline of increasing complexity,from cladistians through teleosts.This is particularly apparent in the posterior tubercle of the diencephalon.In cladistians,the posterior tu...The brains of ray-finned fishes form a morphocline of increasing complexity,from cladistians through teleosts.This is particularly apparent in the posterior tubercle of the diencephalon.In cladistians,the posterior tubercle consists of a periventricular nucleus and a migrated nucleus medianus that is fused across the midline.In more advanced ray-finned fishes,such as gars and bowfins,the posterior tubercle comprises numerous additional mi-grated nuclei,termed the preglomerular complex,in addition to a more well developed nucleus medianus.In teleosts,the most derived ray-finned fishes,there is an even more elaborate preglomerular complex,but there is no recognizable nucleus medianus.In an attempt to explain the variation in the posterior tubercle of the diencephalon in ray-finned fishes,the immunohistochemistry and connections of nucleus medianus were examined in cladistians,gars and bowfins.In each of these taxa,nucleus medianus exhibits large numbers of calretinin-positive neurons and has ascending projections that terminate in several divisions of the pallium.Although teleosts,such as goldfish,also exhibit numerous cell groups in the posterior tubercle that are rich in calretinin,none of these cell groups has connections that are comparable to those of nucleus medianus in non-teleost ray-finned fishes.It is possible,therefore,that nucleus medianus was lost with the origin of teleosts.展开更多
Numerical studies are conducted to explore the noise reduction effect of leading-edge tubercles inspired by humpback whale flippers.Large eddy simulations are performed to solve the flow field,while the acoustic analo...Numerical studies are conducted to explore the noise reduction effect of leading-edge tubercles inspired by humpback whale flippers.Large eddy simulations are performed to solve the flow field,while the acoustic analogy theory is used for noise prediction.In this paper,a baseline airfoil with a straight leading-edge and three bionic airfoils with tubercled leading-edges are simulated.The tubercles have sinusoidal profiles and the profiles are determined by the tubercle wavelength and amplitude.The tubercles used in this study have a fixed wavelength of 0.1c with three different amplitudes of 0.1c,0.15c and 0.2c,where c is the mean chord of the airfoil.The freestream velocity is set to 40 m/s and the chord based Reynolds number is 400,000.The predicted flow field and acoustic field of the baseline airfoil are compared against the experiments and good agreements are found.A considerable noise reduction level is achieved by the leading-edge tubercles and the tubercle with larger amplitude can obtain better noise reduction.The underlying flow mechanisms responsible for the noise reduction are analyzed in detail.展开更多
This paper studies the bionic tubercle airfoils based on the NACA 0020 prototype airfoil,with 7 models derived from different designs of the span-chord ratios and different tubercle types,along with the option of the ...This paper studies the bionic tubercle airfoils based on the NACA 0020 prototype airfoil,with 7 models derived from different designs of the span-chord ratios and different tubercle types,along with the option of the wave airfoil surface matching the leading-edge tubercle.Open water experiments are conducted to test the airfoil profile at a Reynolds number of 3×10^5 and an angle of attack of 0°-30°.Data are recorded by a four-component force balance and the resulted lift,drag,and force moment are analyzed.From the analysis of the hydrodynamic characteristics and the flow field characteristics,it is shown that the stall of the tubercle airfoils is milder without an evident stalling angle as compared with that of the normal airfoil profile.The lift coefficient of the optimized airfoil is significantly elevated at the angle where the NACA 0020 airfoil is in the stall condition.The lift-drag ratio is also markedly improved at the same angle.The optimal airfoil profile is finally identified and a further optimization plan is proposed based on the comparison results against the CFD numerical simulation.展开更多
Infraglenoid tubercle avulsion fractures are extremely rare injuries.We report a 38-year-old male with glenoid cavity fracture and infraglenoid tubercle avulsion of the left shoulder following a fall from bike.He refu...Infraglenoid tubercle avulsion fractures are extremely rare injuries.We report a 38-year-old male with glenoid cavity fracture and infraglenoid tubercle avulsion of the left shoulder following a fall from bike.He refused surgery and was treated nonoperatively.Follow-up radiography and CT at 18 months revealed a malunited infraglenoid tubercle with signs of early glenohumeral osteoarthritis.He did not have shoulder instability or pain and had a fair-good functional outcome.There are no previously published data on the anatomic outcome of nonoperatively treated displaced infraglenoid tubercle avulsion fractures based on CT.展开更多
Introduction: Tuberculosis is a chronic infectious disease that remains a global public health problem. Children, accounting for 10% of cases, are particularly vulnerable to this disease. Based on a case of multifocal...Introduction: Tuberculosis is a chronic infectious disease that remains a global public health problem. Children, accounting for 10% of cases, are particularly vulnerable to this disease. Based on a case of multifocal tuberculosis in a 14-month-old infant, the authors conducted a literature review on this condition. Observation: The case involved a 14-month-old infant referred from a health center for persistent symptoms including anemia, fever, and lateral deviation of the mouth during crying. Clinical examination revealed an infectious and meningeal syndrome, as well as facial paralysis. The results of brain imaging, cerebrospinal fluid examination, fundus examination, and gastric lavage fluid examination led to the conclusion of multifocal tuberculosis in the infant without association with HIV. Improvement was observed one week after the start of antituberculosis treatment, with complete recovery without sequelae after 12 months. Conclusion: Although rare, multifocal tuberculosis does exists and its diagnosis remains challenging in infants. Early treatment generally leads to favorable outcomes, especially in the absence of HIV coinfection.展开更多
Background:Calcaneus is the largest bone of foot and the main load-bearing structure of heel.The incidence of simple calcaneal tubercle avulsion fracture is low,accounting for about 1%to 3%of all calcaneal fractures.B...Background:Calcaneus is the largest bone of foot and the main load-bearing structure of heel.The incidence of simple calcaneal tubercle avulsion fracture is low,accounting for about 1%to 3%of all calcaneal fractures.Beavis II fracture has large bone fracture,obvious displacement,obvious soft tissue irritation,and often leads to skin necrosis.It needs surgical treatment,reduction and fixation as soon as possible.Although open reduction and tension screw internal fixation is used for Beavis II calcaneal tubercle fracture,but the failure rate is more common.Methods:This study retrospectively analyzed the surgical treatment of calcaneal tubercle Beavis II fracture over 55 years old in our hospital from January 2013 to January 2019.The patients were treated with tension screw combined with locking plate,and followed up and analyzed.Results:12 patients in this group were followed up for 12 to 36 months(mean 20 months).After operation,the fracture healed smoothly in all patients,the healing time was 8 to 12 weeks(mean 10.7 weeks),and there were no complications such as poor incision healing,fracture displacement,internal fixation loosening,fracture and so on.When the patients were followed up 18 weeks after operation,the AOFAS score was 47 to 100,with an average of 91.1,of which 8 cases were excellent,3 good and 1 poor,with an excellent and good rate of 91.7%.Conclusion:Our hospital has been treated with tension screw combined with locking plate,fixed firmly,can early functional exercise,achieved good results.展开更多
The majority of orthopaedic surgeons even currentlyagree that primary total arthroplasty in valgus knees with a deformity of more than ten degrees may prove challenging. The unique sets of bone and soft tissue abnorma...The majority of orthopaedic surgeons even currentlyagree that primary total arthroplasty in valgus knees with a deformity of more than ten degrees may prove challenging. The unique sets of bone and soft tissue abnormalities that must be addressed at the time of the operation make accurate axis restoration, component orientation and joint stability attainment a difficult task. Understanding the specific pathologic anatomic changes associated with the valgus knee is a prerequisite so as to select the proper surgical method, to optimize component position and restore soft-tissue balance. The purpose of this article is to review the valgus knee anatomical variations, to assess the best pre-operative planning and to evaluate how to choose the grade of constraint of the implant. It will also be underlying the up-to-date main approaches and surgical techniques be proposed in the English literature both for bone cuts and soft tissue management of valgus knees.展开更多
In order to rapidly diagnose and differentiate tuberculosis from other bacterial infections, a 16S rRNA gene (16s rDNA)-directed multiplex PCR system was developed. In this system, a pair of universal primers and a ...In order to rapidly diagnose and differentiate tuberculosis from other bacterial infections, a 16S rRNA gene (16s rDNA)-directed multiplex PCR system was developed. In this system, a pair of universal primers and a tubercle bacillus (Tb)-specific primer were designed based on highly con- served regions and Tb species-specific variable region of bacterial 16s rDNA. A 360bp fragment was detected in all bacteria tested, and a 210bp fragment was found only in Tb. 19 species of known bac- teria including Tb were used for evaluating specificity, universality and sensitivity of the PCR. Candi- da albicans and human diploid cell served as controls. It was found that both 210bp and 360bp frag- ments were amplified only in Tb, and only 360 bp fragment was detected in other 18 species of gener- al bacteria. Candida albicans and human cells were negative for both 360bp and 2l0bp fragments. The lowest detectable level of the PCR was 10 fg of DNA for Escherichia coli and 100 fg of DNA for Tb. The results indicated that this multiplex PCR system for the simultaneous detection of Tb and other common bacteria had higher specificity and sensitivity, as well as good universality and might be useful to rapidly diagnose bacterial infections and effectively distinguish tuberculosis from other bacterial involvement.展开更多
Anterior knee pain is a common symptom in general orthopedic practice and is reported in 8% of women and 2% of men over the age of 55 years. The treatment of isolated patellofemoral arthritis is controversial. Many pa...Anterior knee pain is a common symptom in general orthopedic practice and is reported in 8% of women and 2% of men over the age of 55 years. The treatment of isolated patellofemoral arthritis is controversial. Many patients can be effectively managed conservatively. Analysis was done on 14 patients (17 knees) with symptomatic isolated patellofemoral osteoarthritis between 2001 and 2007. 3 patients had additional procedures like tibial tubercle osteotomy and lateral release, tibial tubercle osteotomy with medical plication and iliotibial band lengthening and lateral retinacular release. The operation should be viewed as a soft-tissue procedure involving resurfacing of the femoral trochlea and the articular surface of the patella. Proper balance of the extensor mechanism must be done at the time of surgery to ensure correct tracking of the patella which in turn results in the best outcome for the replacement.展开更多
The retroesophageal right subclavian artery may be associated with multiple neurovascular variations, which may impact various cervicothoracic surgeries. During the dissection of 27 cadavers, the authors detected a re...The retroesophageal right subclavian artery may be associated with multiple neurovascular variations, which may impact various cervicothoracic surgeries. During the dissection of 27 cadavers, the authors detected a retroesophageal right subclavian artery in old man arising from distal aortic arch, crossed ventrally by left recurrent laryngeal nerve and dorsally by thoracic duct. On the right side, the aberrant subclavian artery was associated with nonrecurrent laryngeal nerve crossing a large tortuous inferior thyroid artery at multiple intersection points. Importantly, the nonrecurrent laryngeal nerve gave rise to extra laryngeal branch passing over Zuckerkandl’s tubercle of thyroid gland before its termination into the larynx. The relationships of the aberrant subclavian artery in the present case to thoracic duct, recurrent and nonrecurrent laryngeal nerves may have clinical relevance to various operations such as thyroidectomy, esophagectomy and surgical correction of the aberrant vessel. Therefore, these relationships should be well known by surgeons for prevention of iatrogenic damage of essential neurovascular structures during various surgeries.展开更多
基金financial support from the National Natural Science Foundation of China under grand No.11721202。
文摘Two-dimensional time-resolved particle image velocimetry(TR-PIV)and stereographic particle image velocimetry(SPIV)techniques were used to investigate the effect of leading-edge tubercles on the flow over low-aspect-ratio wing models.The angle of attack is fixed at 10°,and the Reynolds number based on chord length is 5.8×10^(3).It is shown that the leading-edge tubercles can effectively mitigate flow separation in the model and also reduce the contribution of wake vortex to the fluctuating energy of flow.Counter-rotating vortex pairs(CVPs)initiated from the peak of leading-edge tubercles can promote nearby momentum exchange,enhance mixing of the flow and increase the energy contained in the boundary layer,which results in resisting the larger adverse pressure gradient.Therefore,it is concluded that CVPs play an important role in mitigating the flow separation for wings with leading-edge tubercles.
基金National Natural Science Foundation of China,No.81801028Natural Science Foundation of Zhejiang Province,No.LQ19H140001.
文摘BACKGROUND Several previous studies have reported an unusual root formation in which a fractured apical fragment of an immature root continued to develop independent of the main root after trauma to an immature tooth.To date,there have been only rare reports of the continuing apical formation of the fractured root associated with dens evaginatus(DE).This paper presents a case of a separated root tip formation associated with a fractured tubercle of DE.CASE SUMMARY An 11-year-old boy was referred for gingival sinus on the buccal side of the right mandibular second premolar(tooth#45).Clinically,tooth#45 was free of caries,but there was a sign of a fractured tubercle of DE on the occlusal surface.Radiography showed that the root canal of tooth#45 was widely radiolucent.A separated root apex was found apically under the main root and was nearly completely formed with an apical orifice at the apical tip.Tooth#45 was diagnosed as tubular fracture of DE with chronic apical periodontitis.A revascularization technique was recommended to treat the tooth.At 3-mo and 1-yr follow-up,the patient remained asymptomatic.Periapical radiography revealed that the separated root tip distally drifted with closure of the apex.However,the root length and thickness of the main root did not increased.CONCLUSION Clinicians should be aware that even if tubercle of DE is fractured in an immature tooth,the root tip may be separated from the main root and completely formed.
文摘BACKGROUND Tibial tubercle osteotomy(TTO) is a well-established surgical technique to deal with a stiff knee in revision total knee arthroplasty(RTKA). However, several reports have described potential osteotomy-related complications such as nonunion, tibial tubercle migration and fragmentation, and metalware related pain.AIM To evaluate the literature and estimate the efficiency of TTO in RTKA in terms of osteotomy union, knee mobility and complications.METHODS MEDLINE, Scopus, and the Cochrane Central Register of Controlled Trials were investigated for completed studies until February 2020. The principle outcome of the study was the incidence of union of the osteotomy. Secondary outcomes were the knee range of motion as well as the TTO-related and overall procedure complication rate.RESULTS Fifteen clinical studies with a total of 593 TTOs were included. The TTO union rate was 98.1%. Proximal migration and anterior knee pain were the most common TTO-related complications accounting for 6.9% and 6.4% of all cases,respectively. However, only 2.2% of cases suffering from anterior knee pain needed hardware removal. Knee flexion was improved from 82.9° preoperatively to 100.1° postoperatively and total knee range of motion was increased from 73.4° before surgery to 97° after surgery. Stiffness requiring manipulation under anesthesia was recorded in 4.6% of cases. No major complications were reported.CONCLUSION The current systematic review supports the use of TTO in RTKA, as it is associated with high union rate, significant improvement in knee motion and low osteotomy-related complication risk that rarely leads to secondary tibial tubercle procedures.
基金supported by the National Natural Science Foundation of China(30560073)the Key Technologies R&D Program of Jiangxi Province,China(200210100210).
文摘To distinguish the taxonomy of Yihuang wild rice found in Yihuang County, Jiangxi Province, China in 1999, the botanical characteristics of Yihuang wild rice were retrieved by genus, and species; at the same time, the tubercle characters on lemma in Yihuang wild rice, O. rufipogon, 0. officinalis, 0. meyeriana, and O. granulata, were also observed by scanning electron microscopy. The retrieval result by genus showed that Yihuang wild rice is Leersia Soland. Ex Swartz., not Oryza L., Hygroryza Nees and Chikusichloa Koidz. The retrieval result by species showed that Yihuang wild rice is L. sayanuka Ohwi, not L. hexandra Swartz., L. japonica (Makino) Honda and L. oryzoides (L.) Swartz. The results of the SEM observation on tubercles on lemma showed that the tubercle characters on lemma of Yihuang wild rice belongs to "inlaid- silica-peak" type, which is different from the three types of wild rice existing in China, O. rufipogon, O. officinalis, O. Meyeriana, and also O. granulata, but is similar to L. tisseranti, thereby gives a proof of the above retrieval results. It could be concluded that Yihuang wild rice does not belong to Oryza L., but to Leersia sayanuka Ohwi of Leersia Soland. Ex Swartz.
文摘BACKGROUND Identification of the morphology of the genial tubercles (GTs) is valuable for different dental applications. The morphological pattern of the GTs is still controversial, and therefore, the study of its morphology using cone beam computed tomography (CBCT) plays a valuable role in resolving the controversy. AIM To assess the morphological pattern, dimensions and position of the GTs using CBCT among a selected Saudi population. METHODS CBCT records of 155 Saudi subjects (49 female and 106 male) were used to assess the pattern and size of the GTs and to determine the distance from the apices of the lower central incisors to the superior border of the incisors (I-SGT) and the distance from the inferior border of the GTs to the menton (IGT-M). RESULTS The results of this study showed that the most common morphological pattern was of two superior GTs and a rough impression below them (36.8%), followed by two superior GTs and a median ridge representing fused inferior GTs below them (22.6%) and a single median eminence or projection (20%). The classically described pattern, of two superior and two inferior GTs placed one above the other, was found in only 14.2% of cases, while 6.4% of the studied cases had no GTs. The mean width and height were 6.23 ± 1.93 mm and 6.67 ± 3.04 mm, respectively, while the mean I-SGT and IGT-M measurements were 8.26 ± 2.7 mm and 8.13 ± 3.07 mm, respectively. CONCLUSION The GTs are a controversial anatomical landmark with wide variation in their morphological pattern. The most common pattern among the studied Saudi sample was of two superior GTs and a rough impression below them, and there were no significant differences between males and females.
文摘Dear Editor,I am Bing Li from the Department of Ophthalmology,Peking Union Medical College Hospital in Beijing, China,and I write to present a case report of choroidal and ciliary body tubercles.Ocular tuberculosis (TB) is an extrapulmonary tuberculous condition with variable manifestations[1].
基金support by the National Natural Science Foundation of China(No.52076179).
文摘Corner stall receives noticeable attention in the aeroengine field as an important phenomenon in highly-load compressors.Non-uniform leading-edge tubercles,as an effective method to delay stall,are introduced into the compressor.In this paper,the shape of leading-edge tubercles was controlled by a third-order Fourier function.To judge corner stall,a more precise stall indicator for compressor cascade with flow control methods was defined.Besides,the total kinetic energy of the secondary flow at large incidence was adopted as a parameter for stall evaluation to save computing resources.The results of multiobjective optimization reveal that the loss coefficient exhibited negligible variation at design incidence,while the total kinetic energy of secondary flow showed a significant reduction at large incidence,resulting in a substantial increase in stall incidence.In the optimal profiling cases,the stall incidencewas delayed from 7.9°to 11.6°.The major purpose of the research is to provide proper design guidelines for nonuniformleading-edge tubercles and uncover the flow controlmechanisms of leading-edge profiling.Hence,the geometric features that meet different optimization objectives were extracted through geometric analysis near the Pareto Front and through Self-OrganizingMap(SOM)dataminingmethods in the optimization database.Besides,flow field analysis reveals the flow control mechanism of leading-edge tubercles.The convex-concave-convex structure at the 0%-70%blade height region can form two branches of leading-edge vortex pairs that are opposite in the rotation direction to the passage vortex.The two branches of leading-edge vortex pairs mixed with the leading-edge separation vortex to form two stronger mixed vortices,which can effectively suppress the development of passage vortex and delay stall incidence.
基金This work was supported by the National Key R&D Program of China(Grant No.2022YFB2402801)the National Natural Science Foundation of China(Grant No.11972250 and 11672206)+1 种基金the Key Program of Tianjin Natural Science Foundation(Grant No.19JCZDJC32000)the Tianjin Natural Science Foundation(Grant No.20JCQNJC01950).
文摘The influences of leading-edge tubercle amplitude on airfoil flow field have been analyzed at high angle of attack.The accuracy of a large eddy simulation(LES)research is validated through quantitative comparisons with corresponding experimental results.Then,a proper orthogonal decomposition(POD)analysis has been carried out based on the unsteady flow field and the fluid mechanisms of corresponding POD modes have been identified.Consequently,the influences of leading-edge tubercle amplitude have been uncovered.Since the streamwise vorticity is larger than that of small amplitude cases,the momentum transfer process at peaks is more obvious for large amplitude,leading to delayed flow separation.Both amplitude and wavelength play important roles in the generation of laminar separation bubble(LSB)at troughs.Moreover,the Karman vortex shedding process takes place at specific trough sections as pairs of periodic spatial structures exist in the dominant POD modes.The destruction of Karman vortex shedding process is strengthened along with the increase of amplitude.
文摘BACKGROUND De-Quervain’s tenosynovitis is a disorder arising from the compression and irritation of the first dorsal extensor compartment of the wrist.Patients who fail conservative treatment modalities are candidates for surgical release.However,risks with surgery include damage to the superficial radial nerve and an incomplete release due to inadequate dissection.Currently,there is a paucity of literature demonstrating the exact anatomic location of the first dorsal extensor compartment in reference to surface anatomy.Thus,this cadaveric study was performed to determine the exact location of the first extensor compartment and to devise a reliable surgical incision to prevent complications.AIM To describe the location of the first dorsal compartment in relation to bony surface landmarks to create replicable surgical incisions.METHODS Six cadaveric forearms,including four left and two right forearm specimens were dissected.Dissections were performed by a single fellowship trained upper extremity orthopaedic surgeon.Distance of the first dorsal compartment from landmarks such as Lister’s tubercle,the wrist crease,and the radial styloid were calculated.Other variables studied included the presence of the superficial radial nerve overlying the first dorsal compartment,additional compartment subsheaths,number of abductor pollicis longus(APL)tendon slips,and the presence of a pseudo-retinaculum.RESULTS Distance from the radial most aspect of the wrist crease to the extensor retinaculum was 5.14 mm±0.80 mm.The distance from Lister’s tubercle to the distal aspect of the extensor retinaculum was 13.37 mm±2.94 mm.Lister’s tubercle to the start of the first dorsal compartment was 18.43 mm±2.01 mm.The radial styloid to the initial aspect of the extensor retinaculum measured 2.98 mm±0.99 mm.The retinaculum length longitudinally on average was 26.82 mm±3.34 mm.Four cadaveric forearms had separate extensor pollicis brevis compartments.The average number of APL tendon slips was three.A pseudo-retinaculum was present in four cadavers.Two cadavers had a superficial radial nerve that crossed over the first dorsal compartment and retinaculum proximally(7.03 mm and 13.36 mm).CONCLUSION An incision that measures 3 mm proximal from the radial styloid,2 cm radial from Lister’s tubercle,and 5 mm proximal from the radial wrist crease will safely place surgeons at the first dorsal compartment.
基金supported by the Science Engineering Research Board(SERB)Department of Science&Technology(DST)+1 种基金Government of India(No.ECR/2017/001199)SERB/DST for their financial assistance in carrying out this research work through Early Career Research Award
文摘Recent research proves that wings with leading-edge tubercles have the ability to perform efficiently in post-stall region over the conventional straight wing. Moreover, the conventional straight wing outperforms the tubercled wing at a pre-stall region which is quintessential. Even though tubercled wing offers great performance enhancement, because of the complexity of the flow, the trough region of the tubercled wing is more prone to flow separation. Henceforth, the present paper aims at surface blowing – an active flow control technique over the tubercled wing to enhance the aerodynamic efficiency by positively influencing its lift characteristics without causing any additional drag penalty. Flow parameters like blowing velocity ratios and the location of blowing were chosen to find the optimised configuration keeping the amplitude and frequency of the leading-edge tubercles constant as 0.12 c and 0.25 c respectively. Numerical investigations were carried out over the baseline tubercled wing and tubercled wing with surface blowing at various blowing jet velocity ratios 0.5, 1 and 2 over four different chordwise locations ranging from 0.3 c to 0.8 c.The results confirm that blowing at various x/c with different blowing velocity ratios performs better than the conventional tubercled wing. Comparatively, blowing velocity ratio 2 at 0.3 c shows peak performance of about 28% enhancement in the lift characteristics relative to the baseline model. Particularly, in the pre-stall region, 25–50% increase in aerodynamic efficiency is evident over the tubercled wing with surface blowing compared with the baseline case. Additionally,attempts were made to delineate the physical significance of the flow separation mechanism due to blowing by visualizing the streamline pattern.
基金supported,in part,by the National Science Foundation(IBN-0236018).
文摘The brains of ray-finned fishes form a morphocline of increasing complexity,from cladistians through teleosts.This is particularly apparent in the posterior tubercle of the diencephalon.In cladistians,the posterior tubercle consists of a periventricular nucleus and a migrated nucleus medianus that is fused across the midline.In more advanced ray-finned fishes,such as gars and bowfins,the posterior tubercle comprises numerous additional mi-grated nuclei,termed the preglomerular complex,in addition to a more well developed nucleus medianus.In teleosts,the most derived ray-finned fishes,there is an even more elaborate preglomerular complex,but there is no recognizable nucleus medianus.In an attempt to explain the variation in the posterior tubercle of the diencephalon in ray-finned fishes,the immunohistochemistry and connections of nucleus medianus were examined in cladistians,gars and bowfins.In each of these taxa,nucleus medianus exhibits large numbers of calretinin-positive neurons and has ascending projections that terminate in several divisions of the pallium.Although teleosts,such as goldfish,also exhibit numerous cell groups in the posterior tubercle that are rich in calretinin,none of these cell groups has connections that are comparable to those of nucleus medianus in non-teleost ray-finned fishes.It is possible,therefore,that nucleus medianus was lost with the origin of teleosts.
基金This work is supported by the National Natural Science Foundation of China(No.52106056,51776174 and 51936010)the National Science and Technology Major Project of China(No.2017-II-0008-0022)+2 种基金the Fundamental Research Funds for the Central Universities(No.31020210QD706)the National Key Laboratory of Science and Technology on Aerodynamic Design and Research(No.614220121050103)the Key Laboratory of Aerodynamic Noise Control(No.ANCL20210104).
文摘Numerical studies are conducted to explore the noise reduction effect of leading-edge tubercles inspired by humpback whale flippers.Large eddy simulations are performed to solve the flow field,while the acoustic analogy theory is used for noise prediction.In this paper,a baseline airfoil with a straight leading-edge and three bionic airfoils with tubercled leading-edges are simulated.The tubercles have sinusoidal profiles and the profiles are determined by the tubercle wavelength and amplitude.The tubercles used in this study have a fixed wavelength of 0.1c with three different amplitudes of 0.1c,0.15c and 0.2c,where c is the mean chord of the airfoil.The freestream velocity is set to 40 m/s and the chord based Reynolds number is 400,000.The predicted flow field and acoustic field of the baseline airfoil are compared against the experiments and good agreements are found.A considerable noise reduction level is achieved by the leading-edge tubercles and the tubercle with larger amplitude can obtain better noise reduction.The underlying flow mechanisms responsible for the noise reduction are analyzed in detail.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.41176074,51409063 and 51209048)the Fundamental Research Funds for the Central Universities(Grant No.P013513013).
文摘This paper studies the bionic tubercle airfoils based on the NACA 0020 prototype airfoil,with 7 models derived from different designs of the span-chord ratios and different tubercle types,along with the option of the wave airfoil surface matching the leading-edge tubercle.Open water experiments are conducted to test the airfoil profile at a Reynolds number of 3×10^5 and an angle of attack of 0°-30°.Data are recorded by a four-component force balance and the resulted lift,drag,and force moment are analyzed.From the analysis of the hydrodynamic characteristics and the flow field characteristics,it is shown that the stall of the tubercle airfoils is milder without an evident stalling angle as compared with that of the normal airfoil profile.The lift coefficient of the optimized airfoil is significantly elevated at the angle where the NACA 0020 airfoil is in the stall condition.The lift-drag ratio is also markedly improved at the same angle.The optimal airfoil profile is finally identified and a further optimization plan is proposed based on the comparison results against the CFD numerical simulation.
文摘Infraglenoid tubercle avulsion fractures are extremely rare injuries.We report a 38-year-old male with glenoid cavity fracture and infraglenoid tubercle avulsion of the left shoulder following a fall from bike.He refused surgery and was treated nonoperatively.Follow-up radiography and CT at 18 months revealed a malunited infraglenoid tubercle with signs of early glenohumeral osteoarthritis.He did not have shoulder instability or pain and had a fair-good functional outcome.There are no previously published data on the anatomic outcome of nonoperatively treated displaced infraglenoid tubercle avulsion fractures based on CT.
文摘Introduction: Tuberculosis is a chronic infectious disease that remains a global public health problem. Children, accounting for 10% of cases, are particularly vulnerable to this disease. Based on a case of multifocal tuberculosis in a 14-month-old infant, the authors conducted a literature review on this condition. Observation: The case involved a 14-month-old infant referred from a health center for persistent symptoms including anemia, fever, and lateral deviation of the mouth during crying. Clinical examination revealed an infectious and meningeal syndrome, as well as facial paralysis. The results of brain imaging, cerebrospinal fluid examination, fundus examination, and gastric lavage fluid examination led to the conclusion of multifocal tuberculosis in the infant without association with HIV. Improvement was observed one week after the start of antituberculosis treatment, with complete recovery without sequelae after 12 months. Conclusion: Although rare, multifocal tuberculosis does exists and its diagnosis remains challenging in infants. Early treatment generally leads to favorable outcomes, especially in the absence of HIV coinfection.
基金the Youth Science and Technology Project of Health Commission of Shanghai Pudong New Area(Project no.PW2020B-5)the Outstanding Clinical Discipline Project of Shanghai Pudong(Grant No.PWYgy2021-04)+4 种基金the Health Industry Clinical Research Project of Shanghai Health Commission(Project no.20224Y0393)the Young Medical Talents Training Program of Pudong Health Committee of Shanghai(Grant No.PWRq 2021-08)the Outstanding Leaders Training Program of Pudong Hospital affiliated to Fudan University(Grant No.LX202201)the Talents Training Program of Pudong Hospital affiliated to Fudan University(Project no.PX202001)the Scientific Research Foundation provided by Pudong Hospital affiliated to Fudan University(Project no.YJRCJJ201906).
文摘Background:Calcaneus is the largest bone of foot and the main load-bearing structure of heel.The incidence of simple calcaneal tubercle avulsion fracture is low,accounting for about 1%to 3%of all calcaneal fractures.Beavis II fracture has large bone fracture,obvious displacement,obvious soft tissue irritation,and often leads to skin necrosis.It needs surgical treatment,reduction and fixation as soon as possible.Although open reduction and tension screw internal fixation is used for Beavis II calcaneal tubercle fracture,but the failure rate is more common.Methods:This study retrospectively analyzed the surgical treatment of calcaneal tubercle Beavis II fracture over 55 years old in our hospital from January 2013 to January 2019.The patients were treated with tension screw combined with locking plate,and followed up and analyzed.Results:12 patients in this group were followed up for 12 to 36 months(mean 20 months).After operation,the fracture healed smoothly in all patients,the healing time was 8 to 12 weeks(mean 10.7 weeks),and there were no complications such as poor incision healing,fracture displacement,internal fixation loosening,fracture and so on.When the patients were followed up 18 weeks after operation,the AOFAS score was 47 to 100,with an average of 91.1,of which 8 cases were excellent,3 good and 1 poor,with an excellent and good rate of 91.7%.Conclusion:Our hospital has been treated with tension screw combined with locking plate,fixed firmly,can early functional exercise,achieved good results.
文摘The majority of orthopaedic surgeons even currentlyagree that primary total arthroplasty in valgus knees with a deformity of more than ten degrees may prove challenging. The unique sets of bone and soft tissue abnormalities that must be addressed at the time of the operation make accurate axis restoration, component orientation and joint stability attainment a difficult task. Understanding the specific pathologic anatomic changes associated with the valgus knee is a prerequisite so as to select the proper surgical method, to optimize component position and restore soft-tissue balance. The purpose of this article is to review the valgus knee anatomical variations, to assess the best pre-operative planning and to evaluate how to choose the grade of constraint of the implant. It will also be underlying the up-to-date main approaches and surgical techniques be proposed in the English literature both for bone cuts and soft tissue management of valgus knees.
文摘In order to rapidly diagnose and differentiate tuberculosis from other bacterial infections, a 16S rRNA gene (16s rDNA)-directed multiplex PCR system was developed. In this system, a pair of universal primers and a tubercle bacillus (Tb)-specific primer were designed based on highly con- served regions and Tb species-specific variable region of bacterial 16s rDNA. A 360bp fragment was detected in all bacteria tested, and a 210bp fragment was found only in Tb. 19 species of known bac- teria including Tb were used for evaluating specificity, universality and sensitivity of the PCR. Candi- da albicans and human diploid cell served as controls. It was found that both 210bp and 360bp frag- ments were amplified only in Tb, and only 360 bp fragment was detected in other 18 species of gener- al bacteria. Candida albicans and human cells were negative for both 360bp and 2l0bp fragments. The lowest detectable level of the PCR was 10 fg of DNA for Escherichia coli and 100 fg of DNA for Tb. The results indicated that this multiplex PCR system for the simultaneous detection of Tb and other common bacteria had higher specificity and sensitivity, as well as good universality and might be useful to rapidly diagnose bacterial infections and effectively distinguish tuberculosis from other bacterial involvement.
文摘Anterior knee pain is a common symptom in general orthopedic practice and is reported in 8% of women and 2% of men over the age of 55 years. The treatment of isolated patellofemoral arthritis is controversial. Many patients can be effectively managed conservatively. Analysis was done on 14 patients (17 knees) with symptomatic isolated patellofemoral osteoarthritis between 2001 and 2007. 3 patients had additional procedures like tibial tubercle osteotomy and lateral release, tibial tubercle osteotomy with medical plication and iliotibial band lengthening and lateral retinacular release. The operation should be viewed as a soft-tissue procedure involving resurfacing of the femoral trochlea and the articular surface of the patella. Proper balance of the extensor mechanism must be done at the time of surgery to ensure correct tracking of the patella which in turn results in the best outcome for the replacement.
文摘The retroesophageal right subclavian artery may be associated with multiple neurovascular variations, which may impact various cervicothoracic surgeries. During the dissection of 27 cadavers, the authors detected a retroesophageal right subclavian artery in old man arising from distal aortic arch, crossed ventrally by left recurrent laryngeal nerve and dorsally by thoracic duct. On the right side, the aberrant subclavian artery was associated with nonrecurrent laryngeal nerve crossing a large tortuous inferior thyroid artery at multiple intersection points. Importantly, the nonrecurrent laryngeal nerve gave rise to extra laryngeal branch passing over Zuckerkandl’s tubercle of thyroid gland before its termination into the larynx. The relationships of the aberrant subclavian artery in the present case to thoracic duct, recurrent and nonrecurrent laryngeal nerves may have clinical relevance to various operations such as thyroidectomy, esophagectomy and surgical correction of the aberrant vessel. Therefore, these relationships should be well known by surgeons for prevention of iatrogenic damage of essential neurovascular structures during various surgeries.