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Experimental study on energy characteristics and ignition performance of recessed multichannel plasma igniter 被引量:3
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作者 Bang-Huang Cai Hui-Min Song +3 位作者 Min Jia Yun Wu Wei Cui Sheng-Fang Huang 《Chinese Physics B》 SCIE EI CAS CSCD 2020年第6期339-348,共10页
In the extreme conditions of high altitude,low temperature,low pressure,and high speed,the aircraft engine is prone to flameout and difficult to start secondary ignition,which makes reliable ignition of combustion cha... In the extreme conditions of high altitude,low temperature,low pressure,and high speed,the aircraft engine is prone to flameout and difficult to start secondary ignition,which makes reliable ignition of combustion chamber at high altitude become a worldwide problem.To solve this problem,a kind of multichannel plasma igniter with round cavity is proposed in this paper,the three-channel and five-channel igniters are compared with the traditional ones.The discharge energy of the three igniters was compared based on the electric energy test and the thermal energy test,and ignition experiments was conducted in the simulated high-altitude environment of the component combustion chamber.The results show that the recessed multichannel plasma igniter has higher discharge energy than the conventional spark igniter,which can increase the conversion efficiency of electric energy from 26%to 43%,and the conversion efficiency of thermal energy from 25%to 73%.The recessed multichannel plasma igniter can achieve greater spark penetration depth and excitation area,which both increase with the increase of height.At the same height,the inlet flow helps to increase the penetration depth of the spark.The recessed multichannel plasma igniter can widen the lean ignition boundary,and the maximum enrichment percentage of lean ignition boundary can reach 31%. 展开更多
关键词 high altitude extreme condition recessed multichannel plasma igniter discharge energy lean ignition boundary
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Characteristics and threshold voltage model of GaN-based FinFET with recessed gate
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作者 Chong Wang Xin Wang Slab +9 位作者 Xue-Feng Zheng Yun Wang Yun-Long He Ye Tianl Qing He Ji Wul Wei Mao Xiao-Hua Ma Jin-Cheng Zhang Yue Hao 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第9期535-539,共5页
In this work, AlGaN/GaN FinFETs with different fin widths have been successfully fabricated, and the recessed-gate FinFETs are fabricated for comparison. The recessed-gate FinFETs exhibit higher transconductance value... In this work, AlGaN/GaN FinFETs with different fin widths have been successfully fabricated, and the recessed-gate FinFETs are fabricated for comparison. The recessed-gate FinFETs exhibit higher transconductance value and positive shift of threshold voltage. Moreover, with the fin width of the recessed-gate FinFETs increasing, the variations of both threshold voltage and the transconductance increase. Next, transfer characteristics of the recessed-gate FinFETs with different fin widths and recessed-gate depths are simulated by Silvaco software. The relationship between the threshold voltage and the AlGaN layer thickness has been investigated. The simulation results indicate that the slope of threshold voltage variation reduces with the fin width decreasing. Finally, a simplified threshold voltage model for recessed-gate FinFET is established,which agrees with both the experimental results and simulation results. 展开更多
关键词 ALGAN/GAN FINFET recessed gate threshold voltage
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Influence of dry-etching damage on the electrical properties of an AlGaN/GaN Schottky barrier diode with recessed anode
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作者 钟健 姚尧 +9 位作者 郑越 杨帆 倪毅强 贺致远 沈震 周桂林 周德秋 吴志盛 张伯君 刘扬 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第9期479-483,共5页
The influences of dry-etching damage on the electrical properties of an AlGaN/GaN Schottky barrier diode with ICPrecessed anode was investigated for the first time. It was found that the turn-on voltage is decreased w... The influences of dry-etching damage on the electrical properties of an AlGaN/GaN Schottky barrier diode with ICPrecessed anode was investigated for the first time. It was found that the turn-on voltage is decreased with the increase of dry-etching power. Furthermore, the leakage currents in the reverse bias region above pinch-off voltage rise as radio frequency(RF) power increases, while below pinch-off voltage, leakage currents tend to be independent of RF power.Based on detailed current–voltage–temperature(I–V –T) measurements, the barrier height of thermionic-field emission(TFE) from GaN is lowered as RF power increases, which results in early conduction. The increase of leakage current can be explained by Frenkel–Poole(FP) emission that higher dry-etching damage in the sidewall leads to the higher tunneling current, while below pinch-off voltage, the leakage is only related to the AlGaN surface, which is independent of RF power. 展开更多
关键词 AlGaN/GaN Schottky barrier diodes recessed anode etching damage TUNNELING
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Novel approach of ultrasound-guided lateral recess block for a patient with lateral recess stenosis: A case report 被引量:1
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作者 Jiao Yang Xin-Ling Li Qing-Bing Li 《World Journal of Clinical Cases》 SCIE 2024年第5期1010-1017,共8页
BACKGROUND Ultrasound guide technology,which can provide real-time visualization of the needle tip and tissues and avoid many adverse events,is widely used in mini-mally invasive therapy.However,the studies on ultraso... BACKGROUND Ultrasound guide technology,which can provide real-time visualization of the needle tip and tissues and avoid many adverse events,is widely used in mini-mally invasive therapy.However,the studies on ultrasound-guided Lateral recess block(LRB)are limited,this is probably because there is no recognized standard method for ultrasound scanning.This study aimed to evaluate the effect of ultrasound-guided LRB in patients with lateral recess stenosis(LRS).CASE SUMMARY A 65-year-old patient complained of low back pain accompanied occasionally by pain and numbness in the left lower limb.Physical examination showed ten-derness on the spinous process and paraspinal muscles from L1 to S1,extensor hallucis longus and tibialis anterior weakness(muscle strength:4-),and a positive straight leg raising test in the left lower limb(60°).Magnetic resonance imaging showed L4–L5 disc degeneration with left LRS and nerve root entrapment.Subsequently,the patient was diagnosed with LRS.This patient was treated with a novel ultrasound-guided LRB approach.The patient’s symptoms significantly improved without any complications at 1 wk postoperatively and at the 3-month follow-up.CONCLUSION This is the first report on the LRS treatment with ultrasound-guided LRB from the contralateral spinous process along the inner side of the articular process by out-plane technique.Further studies are expected to investigate the efficacy and safety of ultrasound-guided LRB for patients with LRS. 展开更多
关键词 Lateral recess stenosis ULTRASOUND Lateral recess block Real-time visualization Low back pain Case report
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A low on-resistance SOI LDMOS using a trench gate and a recessed drain 被引量:2
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作者 葛锐 罗小蓉 +6 位作者 蒋永恒 周坤 王沛 王琦 王元刚 张波 李肇基 《Journal of Semiconductors》 EI CAS CSCD 2012年第7期43-46,共4页
An integrable silicon-on-insulator (SOl) power lateral MOSFET with a trench gate and a recessed drain (TGRD MOSFET) is proposed to reduce the on-resistance. Both of the trench gate extended to the buried oxide (... An integrable silicon-on-insulator (SOl) power lateral MOSFET with a trench gate and a recessed drain (TGRD MOSFET) is proposed to reduce the on-resistance. Both of the trench gate extended to the buried oxide (BOX) and the recessed drain reduce the specific on-resistance (Ron, sp) by widening the vertical conduction area and shortening the extra current path. The trench gate is extended as a field plate improves the electric field distribution. Breakdown voltage (BV) of 97 V and Ron, sp of 0.985 mf2-cm2 (l/os = 5 V) are obtained for a TGRD MOSFET with 6.5/xm half-cell pitch. Compared with the trench gate SOI MOSFET (TG MOSFET) and the conventional MOSFET, Ron' sp of the TGRD MOSFET decreases by 46% and 83% at the same BV, respectively. Compared with the SOI MOSFET with a trench gate and a trench drain (TGTD MOSFET), BV of the TGRD MOSFET increases by 37% at the same Ron,sp. 展开更多
关键词 trench gate recessed drain ON-RESISTANCE breakdown voltage
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Comprehensive analysis of glacier recession(2000-2020)in the Nun-Kun Group of Glaciers,Northwestern Himalaya
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作者 Shakil Ahmad ROMSHOO Ummer AMEEN +1 位作者 Mustafa Hameed BHAT Tariq ABDULLAH 《Journal of Mountain Science》 SCIE CSCD 2024年第3期768-785,共18页
Himalayan glaciers are shrinking rapidly,especially after 2000.Glacier shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger scale.In t... Himalayan glaciers are shrinking rapidly,especially after 2000.Glacier shrinkage,however,shows a differential pattern in space and time,emphasizing the need to monitor and assess glacier changes at a larger scale.In this study,changes of 48 glaciers situated around the twin peaks of the Nun and Kun mountains in the northwestern Himalaya,hereafter referred to as Nun-Kun Group of Glaciers(NKGG),were investigated using Landsat satellite data during 2000-2020.Changes in glacier area,snout position,Equilibrium Line Altitude(ELA),surface thickness and glacier velocity were assessed using remote sensing data supplemented by field observations.The study revealed that the NKGG glaciers have experienced a recession of 4.5%±3.4%and their snouts have retreated at the rate of 6.4±1.6 m·a^(-1).Additionally,there was a 41%increase observed in the debris cover area during the observation period.Using the geodetic approach,an average glacier elevation change of-1.4±0.4 m·a^(-1)was observed between 2000 and 2012.The observed mass loss of the NKGG has resulted in the deceleration of glacier velocity from 27.0±3.7 m·a^(-1)in 2000 to 21.2±2.2 m·a^(-1)in 2020.The ELA has shifted upwards by 83.0±22 m during the period.Glacier morphological and topographic factors showed a strong influence on glacier recession.Furthermore,a higher recession of 12.9%±3.2%was observed in small glaciers,compared to 2.7%±3.1%in larger glaciers.The debris-covered glaciers showed lower shrinkage(2.8%±1.1%)compared to the clean glaciers(9.3%±5%).The glacier depletion recorded in the NKGG during the last two decades,if continued,would severely diminish glacial volume and capacity to store water,thus jeopardizing the sustainability of water resources in the basin. 展开更多
关键词 Nun-Kun range Glacier recession Glacier snout Remote Sensing HIMALAYA Glacier velocity
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Identifying flow regime in the aquifer of fractured rock system in Germi Chai Basin,Iran
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作者 VAEZIHIR Abdorreza SEPEHRIPOUR Ali TABARMAYEH Mehri 《Journal of Mountain Science》 SCIE CSCD 2024年第2期574-589,共16页
Considering the importance of fractured rock aquifers in the hydrogeologic process,this research aimed to analyze the flow regime,internal degree of karstification,and estimate storage volume in fractured rock aquifer... Considering the importance of fractured rock aquifers in the hydrogeologic process,this research aimed to analyze the flow regime,internal degree of karstification,and estimate storage volume in fractured rock aquifers of the Germi Chai Basin in northwest Iran,which is attributed to its active tectonics,erosion,and the lithological diversity.Given the geological setting,the hypothesis is that this basin is characterized by a high degree of karstification and diffuse or intermediate flow regime leading to variation in discharge flow rate.The hydrodynamic and hadrochemical analysis was conducted on 9 well distributed springs across the basin from 2019 to 2020.The maximum flow rate in most of the springs appeared in the early wet season despite their different levels of fluctuations on the monthly discharge time series.Analyzing the spring recession curve form revealed an aquifer containing multiple micro-regimes withαrecession coefficients and a degree of karstification ranging between 0.001 to 0.06 and 0.55 to 2.61,respectively.These findings indicated a dominant diffuse and intermediate flow system resulting from the development of a high density of fractures in this area.The electrical conductivity of the spring changes inversely proportional to the change in flow discharge,indicating the reasonable hydrological response of the aquifer to rainfall events.Hydrograph analysis revealed that the delay time of spring discharge after rainfall events mostly varies between 10 to 30 days.The total dynamic storage volume of the spring for a given period(2019-2020)was estimated to be approximately 1324 million cubic meters reflecting the long-term drainage potential and high perdurability of dynamic storage.Estimating the maximum and minimum ratio revealed that the springs recharging system in Germi Chai Basin comes under the slow aquifers category.This finding provides valuable insight into the hydrogeological properties of fractured rock aquifers contributing to effective water management strategy. 展开更多
关键词 Fractured rock aquifer Hydrodynamic and hadrochemical analysis Germi Chai Basin Recession coefficient
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Detection of Novel BEST1 Variations in Autosomal Recessive Bestrophinopathy Using Third-generation Sequencing
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作者 Jia-xun LI Ling-rui MENG +6 位作者 Bao-ke HOU Xiao-lu HAO Da-jiang WANG Ling-hui QU Zhao-hui LI Lei ZHANG Xin JIN 《Current Medical Science》 SCIE CAS 2024年第2期419-425,共7页
Objective:Autosomal recessive bestrophinopathy(ARB),a retinal degenerative disease,is characterized by central visual loss,yellowish multifocal diffuse subretinal deposits,and a dramatic decrease in the light peak on ... Objective:Autosomal recessive bestrophinopathy(ARB),a retinal degenerative disease,is characterized by central visual loss,yellowish multifocal diffuse subretinal deposits,and a dramatic decrease in the light peak on electrooculogram.The potential pathogenic mechanism involves mutations in the BEST1 gene,which encodes Ca2+-activated Cl−channels in the retinal pigment epithelium(RPE),resulting in degeneration of RPE and photoreceptor.In this study,the complete clinical characteristics of two Chinese ARB families were summarized.Methods:Pacific Biosciences(PacBio)single-molecule real-time(SMRT)sequencing was performed on the probands to screen for disease-causing gene mutations,and Sanger sequencing was applied to validate variants in the patients and their family members.Results:Two novel mutations,c.202T>C(chr11:61722628,p.Y68H)and c.867+97G>A,in the BEST1 gene were identified in the two Chinese ARB families.The novel missense mutation BEST1 c.202T>C(p.Y68H)resulted in the substitution of tyrosine with histidine in the N-terminal region of transmembrane domain 2 of bestrophin-1.Another novel variant,BEST1 c.867+97G>A(chr11:61725867),located in intron 7,might be considered a regulatory variant that changes allele-specific binding affinity based on motifs of important transcriptional regulators.Conclusion:Our findings represent the first use of third-generation sequencing(TGS)to identify novel BEST1 mutations in patients with ARB,indicating that TGS can be a more accurate and efficient tool for identifying mutations in specific genes.The novel variants identified further broaden the mutation spectrum of BEST1 in the Chinese population. 展开更多
关键词 autosomal recessive bestrophinopathy BEST1 gene third-generation sequencing MUTATION
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New recessive compound heterozygous variants of RP1L1 in RP1L1 maculopathy
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作者 Wen-Chao Cao Qing-Shan Chen +2 位作者 Run Gan Tao Huang Xiao-He Yan 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2024年第1期107-112,共6页
AIM:To identify a maculopathy patient caused by new recessive compound heterozygous variants in RP1L1.METHODS:Comprehensive retinal morphological and functional examinations were evaluated for the patient with RP1L1 m... AIM:To identify a maculopathy patient caused by new recessive compound heterozygous variants in RP1L1.METHODS:Comprehensive retinal morphological and functional examinations were evaluated for the patient with RP1L1 maculopathy.Targeted sequence capture array technique was used to screen potential pathologic variants.Polymerase chain reaction and Sanger sequencing were used to confirm the screening results.RESULTS:Fundus examination showed round macular lesions appeared in both eyes.Optical coherence tomography showed that the inner segment/outer segment continuity was disorganized and disruptive in the left eye,but it was uneven and slightly elevated in the right eye.Fundus autofluorescence showed patchy hyper-autofluorescence in the macula.Visual field examination indicates central defects in both eyes.Electroretinogram(ERG)and multifocal ERG showed no obvious abnormalities.Fundus fluorescein angiography in the macula showed obviously irregular hyper-fluorescence in the right eye and slightly hyper-fluorescence in the left eye.We found that the proband carried a missense variant(c.1972C>T)and a deletion variant(c.4717_4718del)of RP1L1,which were originated from the parents and formed compound heterozygous variants.Both variants are likely pathogenic according to the ACMG criteria.Multimodal imaging,ERG and detailed medical history are important diagnostic tools for differentiating between acquired and inherited retinal disorders.CONCLUSION:A maculopathy case with detailed retinal phenotype and new recessive compound heterozygous variants of RP1L1 is identified in a Chinese family,which expands the understanding of phenotype and genotype in RP1L1 maculopathy. 展开更多
关键词 MACULOPATHY RECESSIVE compound heterozygous variants RP1L1
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3M syndrome patient with a novel mutation:A case rep
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作者 Ming-Ran Luo Si-Ming Dai +7 位作者 Yin Li Qian Wang Hao Liu Peng Gao Jia-Yun Liu Jian Chen Shu-Jie Zhao Guo-Yong Yin 《World Journal of Clinical Cases》 SCIE 2024年第8期1454-1460,共7页
BACKGROUND A rare autosomal recessive genetic disorder,3M syndrome,is characterized by severe intrauterine and postnatal growth retardation.Children with 3M syndrome typically exhibit short stature,facial deformities,... BACKGROUND A rare autosomal recessive genetic disorder,3M syndrome,is characterized by severe intrauterine and postnatal growth retardation.Children with 3M syndrome typically exhibit short stature,facial deformities,long tubular bones,and high vertebral bodies but generally lack mental abnormalities or other organ damage.Pathogenic genes associated with 3M syndrome include CUL7,OBSL1 and CCDC8.The clinical and molecular characteristics of patient with 3M syn-drome are unique and serve as important diagnostic indicators.CASE SUMMARY In this case,the patient displayed square shoulders,scoliosis,long slender tubular bones,and normal neurological development.Notably,the patient did not exhibit the typical dysmorphic facial features,relative macrocephaly,or growth retardation commonly observed in individuals with 3M syndrome.Whole exon sequencing revealed a novel heterozygous c.56681+1G>C(Splice-3)variant and a previously reported nonsense heterozygous c.3341G>A(p.Trp1114Ter)variant of OBSL1.Therefore,it is important to note that the clinical features of 3M syndrome may not always be observable,and genetic confirmation is often required.Additionally,the identification of the c.5683+1G>C variant in OBSL1 is notewor-thy because it has not been previously reported in public databases.CONCLUSION Our study identified a new variant(c.5683+1G>C)of OBSL1 that contributes to expanding the molecular profile of 3M syndrome. 展开更多
关键词 3M syndrome CUL7 OBSL1 CCDC8 Autosomal recessive Case report
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Factors that influence the results of indirect decompression employing oblique lumbar interbody fusion
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作者 Andrey E Bokov Svetlana Y Kalinina +2 位作者 Mingiyan I Khaltyrov Alexandr P Saifullin Anatoliy A Bulkin 《World Journal of Orthopedics》 2024年第8期734-743,共10页
BACKGROUND Indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal stenosis.On the other hand,the reported rate of revision surgery after indirect decompression highl... BACKGROUND Indirect decompression is one of the potential benefits of anterior reconstruction in patients with spinal stenosis.On the other hand,the reported rate of revision surgery after indirect decompression highlights the necessity of working out prediction models for the radiographic results of indirect decompression with assessing their clinical relevance.AIM To assess factors that influence radiographic and clinical results of the indirect decompression in patients with stenosis of the lumbar spine.METHODS This study is a single-center cross-sectional evaluation of 80 consecutive patients(17 males and 63 females)with lumbar spinal stenosis combined with the instability of the lumbar spinal segment.Patients underwent single level or bisegmental spinal instrumentation employing oblique lumbar interbody fusion(OLIF)with percutaneous pedicle screw fixation.Radiographic results of the indirect decompression were assessed using computerized tomography,while MacNab scale was used to assess clinical results.RESULTS After indirect decompression employing anterior reconstruction using OLIF,the statistically significant increase in the disc space height,vertebral canal square,right and left lateral canal depth were detected(Р<0.0001).The median(M)relative vertebral canal square increase came toМ=24.5%with 25%-75%quartile border(16.3%;33.3%)if indirect decompression was achieved by restoration of the segment height.In patients with the reduction of the upper vertebrae slip,the median of the relative increase in vertebral canal square accounted for 49.5%with 25%-75%quartile border(2.35;99.75).Six out of 80 patients(7.5%)presented with unsatisfactory results because of residual nerve root compression.The critical values for lateral recess depth and vertebral canal square that were associated with indirect decompression failure were 3 mm and 80 mm2 respectively.CONCLUSION Indirect decompression employing anterior reconstruction is achieved by the increase in disc height along the posterior boarder and reduction of the slipped vertebrae in patients with degenerative spondylolisthesis.Vertebral canal square below 80 mm2 and lateral recess depth less than 3 mm are associated with indirect decompression failures that require direct microsurgical decompression. 展开更多
关键词 Indirect decompression Anterior reconstruction Central lumbar spinal stenosis Degenerative spondylolisthesis Lateral recess stenosis Spinal instability Oblique lateral interbody fusion
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Methylmalonic Acidemia: An Unusual Cause of Chronic Renal Disease in Adults
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作者 Kamel El Reshaid Abdulrahman Al Kanderi 《Open Journal of Nephrology》 2024年第3期334-339,共6页
Background: Methylmalonic aciduria (MMA) is a genetic disorder of aminoacid metabolism, due to mutations in methylmalonyl-CoA mutase, which leads to the accumulation of methylmalonic acid in body fluids. Patients typi... Background: Methylmalonic aciduria (MMA) is a genetic disorder of aminoacid metabolism, due to mutations in methylmalonyl-CoA mutase, which leads to the accumulation of methylmalonic acid in body fluids. Patients typically present at the age of 1 month to 1 year with dehydration, renal impairment as well as neurologic manifestations viz. seizure, encephalopathy, strokes and disease in the globus pallidi. The case: a 26-year-old man presented with severe acute on top of chronic renal disease with serum creatinine at 590 umol/L and bilateral 8 cm kidneys with thin and echogenic cortex. He had: (a) hypernatremic dehydration, metabolic acidosis and high ammonia level with (b) a history of multiple similar attacks since the age of 8 months. Diagnosis of MMA was confirmed by high serum and urine enzymatic levels as well as genetic testing. His initial management included support with replacements of fluids, electrolytes, and bicarbonates as well as intravenous dextrose, vitamin B12 and broad-spectrum antibiotic (Meropenem) for his chest infection. Subsequently, he received 1) CARBAGLU (carglumic acid) for 7 days to lower his ammonia level to Conclusion: Untreated homozygous MMA variants, can achieve adulthood with significant renal disease yet their morbidity and mortality can be ameliorated with diet and specific therapy. 展开更多
关键词 Methylmalonic Acidemia Kidney Failure Metabolic Acidosis Autosomal Recessive Amino Acid Disorder Kreps Cycle Hyperammonia Vitamin 12 CARNITINE
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GaN metal-oxide-semiconductor field-effect transistors on AIGaN/GaN heterostructure with recessed gate
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作者 Qingpeng WANG Jin-Ping AO +4 位作者 Pangpang WANG Ying JIANG Liuan LI Kazuya KAWAHARADA Yang LIU 《Frontiers of Materials Science》 SCIE CSCD 2015年第2期151-155,共5页
GaN metal-oxide-semiconductor field-effect transistors (MOSFETs) on AIGaN/GaN heterostructure with a recess gate were fabricated and characterized. The device showed good pinch-off characteristics and a maximum fiel... GaN metal-oxide-semiconductor field-effect transistors (MOSFETs) on AIGaN/GaN heterostructure with a recess gate were fabricated and characterized. The device showed good pinch-off characteristics and a maximum field-effect mobility of 145.2 cm2.V-1.s-1. The effects of etching gas of CI2 and SiCI4 were investigated in the gate recess process. SiCI4-etched devices showed higher channel mobility and lower threshold voltage. Atomic force microscope measurement was done to investigate the etching profile with different etching protection mask. Compared with photoresist, SiO2- masked sample showed lower surface roughness and better profile with stepper sidewall and weaker trenching effect resulting in higher channel mobility in the MOSFET. 展开更多
关键词 gallium nitride MOSFET recess gate dry etching
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PIC-integrable,uniformly tensile-strained Ge-on-insulator photodiodes enabled by recessed SiN_(x) stressor
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作者 YIDING LIN DANHAO MA +5 位作者 KWANG HONG LEE RUI-TAO WEN GOVINDO SYARANAMUAL LIONEL CKIMERLING CHUAN SENG TAN JURGEN MICHEL 《Photonics Research》 SCIE EI CAS CSCD 2021年第7期1255-1263,共9页
Mechanical strain engineering has been promising for many integrated photonic applications. However,for the engineering of a material electronic bandgap,a trade-off exists between the strain uniformity and the integra... Mechanical strain engineering has been promising for many integrated photonic applications. However,for the engineering of a material electronic bandgap,a trade-off exists between the strain uniformity and the integration compatibility with photonic-integrated circuits (PICs). Herein,we adopted a straightforward recess-type design of a silicon nitride (SiNx) stressor to achieve a uniform strain with enhanced magnitude in the material of interest on PICs. Normal-incidence,uniformly 0.56% tensile strained germanium (Ge)-on-insulator (GOI) metal-semiconductor-metal photodiodes were demonstrated,using the recessed stressor with 750 MPa tensile stress. The device exhibits a responsivity of 1.840.15 A∕W at 1550 nm. The extracted Ge absorption coefficient is enhanced by -3.2×to 8340 cm^(-1) at 1612 nm and is superior to that of In_(0.53)Ga_(0.47)As up to 1630 nm limited by the measurement spectrum. Compared with the nonrecess strained device,additional absorption coefficient improvement of 10%–20% in the C-band and 40%–60% in the L-band was observed. This work facilitates the recessstrained GOI photodiodes for free-space PIC applications and paves the way for various (e.g.,Ge,GeSn or III-V based) uniformly strained photonic devices on PICs. 展开更多
关键词 RECESS STRAINED stress
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The impact of earlier flood recession on metacommunity diversity of wintering waterbirds at shallow lakes in the middle and lower Yangtze River floodplain 被引量:2
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作者 Zhenhua Wei Lizhi Zhou 《Avian Research》 SCIE CSCD 2023年第2期223-230,共8页
The hydrological regime in wetlands plays an important role in the process of wintering waterbird metacommunity assemblage.However,increasing frequency of extreme climate and the intensification of human activities,su... The hydrological regime in wetlands plays an important role in the process of wintering waterbird metacommunity assemblage.However,increasing frequency of extreme climate and the intensification of human activities,such as the construction of sluices and dams,have resulted in frequently abnormal hydrological regime in the middle and lower Yangtze River floodplain.In recent years,earlier flood recession has become one of the main hydrological problems faced in the shallow lakes,having a great impact on wetland biodiversity.It is necessary to understand the impact of earlier flood recession on waterbirds,an indicator of wetland biodiversity,and the metacommunity concept is helpful to elucidate the underlying mechanism involved in the processes of assemblage by waterbird communities.In this study,we surveyed the wintering waterbirds at three sub-lakes of Caizi Lakes during 2019-2020 and 2020-2021 and compared the richness,abundance,alpha and beta diversity of waterbirds in and among local metacommunities under earlier flood recession and normal hydrological regime.The results showed that the earlier flood recession reduced the species richness in the early stage and abundance in the late stage,it also reduced the Shannon-Wiener index in the early stage and increased the dissimilarity between and within waterbird metacommunities in the late stage.The partition of beta diversity showed that the turnover component played a major role in the process of waterbird metacommunity assemblage.It was found that the earlier flood recession reduced the richness,abundance in different stages of flood recession,which also increased the turnover of waterbirds.Metacommunities with high habitat heterogeneity had better resistance to abnormal hydrological regime,which resulted in high dissimilarity between and within metacommunities.The results of this study provide important information for waterbird conservation and water level management at shallow lakes in the middle and lower Yangtze River floodplain. 展开更多
关键词 Beta diversity Flood recession Hydrological regime METACOMMUNITY Shallow lake WATERBIRDS
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The R2R3-MYB transcription factor GaPC controls petal coloration in cotton
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作者 Caiping Cai Fan Zhou +4 位作者 Weixi Li Yujia Yu Zhihan Guan Baohong Zhang Wangzhen Guo 《The Crop Journal》 SCIE CSCD 2023年第5期1319-1330,共12页
Although a few cases of genetic epistasis in plants have been reported, the combined analysis of genetically phenotypic segregation and the related molecular mechanism remains rarely studied. Here, we have identified ... Although a few cases of genetic epistasis in plants have been reported, the combined analysis of genetically phenotypic segregation and the related molecular mechanism remains rarely studied. Here, we have identified a gene(named GaPC) controlling petal coloration in Gossypium arboreum and following a heritable recessive epistatic genetic model. Petal coloration is controlled by a single dominant gene,GaPC. A loss-of-function mutation of GaPC leads to a recessive gene Gapc that masks the phenotype of other color genes and shows recessive epistatic interactions. Map-based cloning showed that GaPC encodes an R2R3-MYB transcription factor. A 4814-bp long terminal repeat retrotransposon insertion at the second exon led to GaPC loss of function and disabled petal coloration. GaPC controlled petal coloration by regulating the anthocyanin and flavone biosynthesis pathways. Expression of core genes in the phenylpropanoid and anthocyanin pathways was higher in colored than in white petals. Petal color was conferred by flavonoids and anthocyanins, with red and yellow petals rich in anthocyanin and flavonol glycosides, respectively. This study provides new insight on molecular mechanism of recessive epistasis,also has potential breeding value by engineering GaPC to develop colored petals or fibers for multifunctional utilization of cotton. 展开更多
关键词 COTTON Petal color R2R3-MYB transcription factor LTR-RT insertion Flavonoid/anthocyanin biosynthesis Recessive epistasis
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Compound heterozygous mutations in tripeptidyl peptidase 1 cause rare autosomal recessive spinocerebellar ataxia type 7:A case report
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作者 Rui-Han Liu Xin-Yu Wang +5 位作者 Yuan-Yuan Jia Xing-Chen Wang Min Xia Qiong Nie Jia Guo Qing-Xia Kong 《World Journal of Clinical Cases》 SCIE 2023年第27期6618-6623,共6页
BACKGROUND Spinocerebellar ataxia recessive type 7(SCAR7)is a rare clinical manifestation beginning in childhood or adolescence.SCAR7 is caused by tripeptidyl peptidase 1(TPP1)gene mutations,and presents with cerebell... BACKGROUND Spinocerebellar ataxia recessive type 7(SCAR7)is a rare clinical manifestation beginning in childhood or adolescence.SCAR7 is caused by tripeptidyl peptidase 1(TPP1)gene mutations,and presents with cerebellar ataxia,pyramidal signs,neurocognitive impairment,deep paresthesia,and cerebellar atrophy.CASE SUMMARY Here,we describe a 25-year-old female patient in China who presented with increasing difficulty walking,falling easily,shaking limbs,instability holding items,slurred speech,coughing when drinking,palpitations,and frequent hunger and overeating.Magnetic resonance imaging showed cerebellar atrophy.Whole exome sequencing detected two compound heterozygous mutations in the TPP1 gene:c.1468G>A p.Glu490Lys and c.1417G>A p.Gly473Arg.Considering the patient’s clinical presentation and genetic test results,we hypothesized that complex heterozygous mutations cause TPP1 enzyme deficiency,which may lead to SCAR7.CONCLUSION We report the first case of SCAR7 from China.We also identify novel compound heterozygous mutations in the TPP1 gene associated with SCAR7,expanding the range of known disease-causing mutations for SCAR7. 展开更多
关键词 Spinocerebellar ataxia recessive type 7 Tripeptidyl peptidase 1 Compound heterozygous variant Case report
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In Vitro Evaluation of Two Tissue Substitutes for Gingival Augmentation
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作者 Tulio Cardoso dos Santos Carlos Nelson Elias +4 位作者 Alexandre Barboza Lemos Andresa Borges Soares André Antonio Pelegrine Lucas Novaes Teixeira Elizabeth Ferreira Martinez 《Journal of Biomaterials and Nanobiotechnology》 CAS 2023年第2期23-34,共12页
Three-dimensional collagen matrices of porcine origin are being used as substitutes for soft tissue grafts in periodontal plastic surgery in search of aesthetic and natural results. This in vitro study aimed to compar... Three-dimensional collagen matrices of porcine origin are being used as substitutes for soft tissue grafts in periodontal plastic surgery in search of aesthetic and natural results. This in vitro study aimed to compare Fibro-Gide® (GeistlichBiomaterials) and Mucoderm® (BotissBiomaterials) matrices during the initial phase of soft tissue formation. For this purpose, samples of 5 × 5 mm were obtained, and then human fibroblasts were plated on them. After 24, 48 and 72 h, cell viability was assessed using an MTT assay, and the secretion of type I collagen, MMP-2, TIMP-1 and TIMP-2 was analyzed by ELISA immunoassay. The control group (C) consisted of cells plated on polystyrene without the matrices. The morphology of the surfaces was also examined using scanning electron microscopy (SEM), as was the average roughness (Ra) of the samples by a profilometer. Topographic analysis revealed that roughness was significantly higher on Mucoderm® than on Fibro-Gide® (p 0.05). The synthesis of type I collagen, MMP-2 and TIMP-1 were significantly higher from cells plated on Fibro-Gide® than on Mucoderm®, in all time points (p ® than on Mucoderm® (p ® induced an increase in type I collagen, MMP-2 and TIMP-1 and TIMP-2. 展开更多
关键词 Collagen Matrices Gingival Recession Periodontal Regeneration Matrix Metalloproteinases
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Study of the Impact of Climate Change on Water Resources in the Sangha Watershed at Ouesso Hydrological Station, Republic of the Congo-Brazzaville (1961-2020)
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作者 Guy Blanchard Matete Moukoko Christian Ngoma Mvoundou +2 位作者 Joseph Mangouende Roddy Lendzea Christian Tathy 《Journal of Water Resource and Protection》 2023年第11期611-630,共20页
The Sangha River basin is the largest sub-basin of the Congo River basin, which drains the northern part of the Republic of the Congo-Brazzaville. It is the most important economic zone in this part of the country, wi... The Sangha River basin is the largest sub-basin of the Congo River basin, which drains the northern part of the Republic of the Congo-Brazzaville. It is the most important economic zone in this part of the country, with a strong timber industry, agriculture and hydroelectricity. The catchment also boasts the country’s third-largest river port, located in the town of Ouesso. Unfortunately, increasingly frequent low-water levels in recent years have led to a decline in river navigation and economic activities. So, the aim of this study is to show the effects of climate change over the last six decades in the Sangha watershed at Ouesso hydrological station, located in the north of the Republic of the Congo-Brazzaville, and elucidate its impact on water resources. To achieve this, several statistical and hydrological methods were used. The application of change-point or shift detection tests to flow series from 1961 to 2020 revealed variability in the hydrological cycle, characterized by two major phases of homogeneous flows: a wet surplus phase and a dry deficit phase. The results show one shift in flood flows in 1971 (Buishand test), one shift in yearly average flows or modules in 1971 (Pettitt test and Buishand test), and one shift in low-water flows in 1976, with all two tests. These disruptions were accompanied by a drop in flow of around 15.63%, 21.70% and 35.67%, on average, for floods, modules, and low-water, respectively, a drop in rainfall of around 9.6% and a rise in temperature of around 0.76?C. These flows show an overall downward trend. The calculated recession coefficients show that, over the entire study period, a recession occurred in March 1985. 展开更多
关键词 Sangha Watershed Republic of the Congo Pettitt Test Buishand Test CHANGE-POINT Recession Coefficient
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Mathematical Foundations of Sustainable Economy Development
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作者 Nicholas Simon Gonchar 《Advances in Pure Mathematics》 2023年第6期369-401,共33页
The principles of sustainable economic development are formulated on the basis of the developed concept of description of economic systems. Mathematical algorithms for finding equilibrium states were built and the con... The principles of sustainable economic development are formulated on the basis of the developed concept of description of economic systems. Mathematical algorithms for finding equilibrium states were built and the conditions for complete clearing of the markets were found. The definition of the phenomenon of recession is given and theorems are established that formulate the conditions for the existence of a recession in the economic system. The recession depth parameter is introduced. For the input-output production model, the necessary and sufficient conditions under which the economic system functions in a profitable mode have been established. The conditions for supply vectors of firms for special technological mappings and consumers demand under which complete clearing of markets takes place are found. 展开更多
关键词 Technological Mapping Economic Equilibrium Clearing Market Recession Phenomenon Sustainable Economic Development
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