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Directionality based fast fractional pel motion estimation for H.264

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Journal of Systems Engineering and Electronics 2009年第3期20卷 457-462页

作者： Zhang Wei Fan fen Wang Xiaoyang zhu Weile School of Electronic Engineering Univ. of Electronic Science and Technology of China Chengdu 610054 P. R. China

Motion estimation is an important and intensive task in video coding applications. Since the complexity of integer pixel search has been greatly reduced by the numerous fast ME algorithm, the computation overhead required by fractional pixel ME has become relatively significant. To reduce the complexity of the fractional pixel ME algorithm, a directionality-based fractional pixel ME algorithm is proposed. The proposed algorithm efficiently explores the neighborhood positions which with high probability to be the best matching around the minimum one and skips over other unlikely ones. Thus, the proposed algorithm can complete the search by examining only 3 points on appropriate condition instead of 17 search points in the search algorithm of reference software. The simulation results show that the proposed algorithm successfully optimizes the fractional-pixel motion search on both half and quarter-pixel accuracy and improves the processing speed with low PSNR penalty.

关键词： fast encoding fractional pel motion search

Effect of medical care linkage-continuous management mode in patients with posterior circulation cerebral infarction undergoing endovascular interventional therapy

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World Journal of Clinical Cases 2022年第29期10卷 10478-10486页

作者： fen-Xia zhu Qian Ye Department of Interventional Medicine The First Affiliated Hospital of Soochow UniversitySuzhou 215006Jiangsu ProvinceChina

BACKGROUND Acute cerebral infarction is a severe type of ischemic stroke that can be divided into anterior circulation cerebral infarction and posterior circulation cerebral infarction(PCCI).PCCI affects the structure of the posterior circulation brain,because posterior part of the brain,which has more complex anatomical structures and more prone to posterior circulation vascular ***,improving the prognosis of PCCI patients is *** To explore the effect of medical care linkage-continuous management mode(MCLMM)on endovascular interventional therapy(EIT)for *** Sixty-nine patients with PCCI who received EIT and conventional nursing intervention were selected as the control group,and 78 patients with PCCI who received EIT and MCLMM intervention were selected as the observation *** incidence of postoperative complications,compliance and disease selfmanagement behavior after six months of intervention,modified Rankin scale(mRS)and Barthel index(BI)scores in the acute phase and after one year of intervention,and recurrence within one year were compared between the two *** The total incidence rate of postoperative complications in the observation group(7.69%)was lower than that in the control group(18.84%)(P<0.05).The scores for medical compliance behavior(regular medication,appropriate diet,and rehabilitation cooperation rates)and disease self-management behavior(self-will,disease knowledge,and self-care ability)in the observation group were higher than those in the control group(P<0.05).After one year of intervention,in the observation group,the mRS score was significantly lower,and the BI score was significantly higher than those in the control group(P<0.05).The recurrence rate within one year in the observation group(3.85%)was significantly lower than that in the control group(13.04%)(P<0.05).CONCLUSION MCLMM can reduce the incidence of complications after EIT for PCCI,improve patient compliance behavior and disease se

关键词： Medical care linkage-continuous management mode Posterior circulation cerebral infarction Cerebral infarction Medical care Interventional therapy

Insecticidal activities of garlic substances against adults of grain moth, Sitotroga cerealella （Lepidoptera： Gelechiidae）

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Insect Science 2012年第2期19卷 205-212页

作者： feng-Lian Yang fen zhu Chao-Liang Lei Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory Huazhong Agricultural UniversityWuhanChina

The angoumois grain moth, Sitotroga cerealella （Olivier）, is one of the most serious stored grain pests around the world. In attempts to reduce the losses caused by the moth and to suppress its populations, the fumigant activities, behavioral influence and ovipositional inhibition of garlic （Allium sativum） essential oil and its two major components, diallyl disulfide and diallyl trisulfide, were investigated against the adult grain moth. Their effects on reduction in survival of first instar larvae to adult emergence were also evaluated. Results showed that these three materials （garlic essential oil, diallyl disulfide and diallyl trisulfide） had significant fumigant activity with 50% lethal concentration values at 1.33, 0.99, and 1.02/zL/L air space, respectively; meanwhile, the three materials possessed high behavioral deterrent activities against adults in the Y-tube olfactometer. When applied to rice grains, these materials reduced adult longevity and inhibited oviposition, with ovipositional inhibition above 70% at a concentration of 1.5uL/25 g in either no-choice or two-choice tests. In short, the study showed that both diallyl disulfide and diallyl trisulfide, like garlic essential oil, acted as fitrnigants, produced behavioral deter- rence and inhibited oviposition against angoumois grain moth. Our work here indicates that diallyl disulfide and diallyl trisulfide may serve as potential alternatives for grain protectants since both of them can be prepared easily from readily available chemicals.

关键词： behavioral deterrence essential oil fumigant garlic oviposition inhibition,Sitotroga cerealella

Preparation of SiC_p/Al_2O_3-Al Composites by Directed Metal Oxidation

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Chinese Journal of Aeronautics 2006年第B12期19卷 47-50页

作者： LIN Ying YANG Hai-bo WANG fen zhu Jian-feng School of Materials Science and Engineering Shaanxi University of Science ＆ Technology Xianyang 712081 China

SiCp/Al2O3-Al composites were synthesized by means of direct metal oxidation method. The composition and microstructures of the composites were investigated using X-ray diffraction （XRD）, scanning electron microscopy （SEM） and metallurgical microscope. The effects of technical parameters on the properties of the product were analyzed. The results indicate that the composite possesses a dense microstructure, composed of three interpenetrated phases. Of them, SiO2 layer prohibits the powdering of the composites; Mg promotes the wetting and infiltration of the system and Si restricts the interfacial reaction while improving the wetting ability between reinforcement and matrix.

关键词： SiCD/Al2O3-Al composites: directed metal oxidation Al-Mg-Si alloy SiC reinforcement

Eicosanoids mediate nodulation reactions to bacterial Escherichia coil K 12 infections in larvae of the oriental blowfly, Chrysomya megacephala

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Insect Science 2009年第5期16卷 387-392页

作者： Fu Zhao Bing Chen Yong Wang fen zhu Chao-Liang Lei Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory Huazhong Agricultual University Wuhan China State Key Laboratory of Integrated Management of Pest Insects and Rodents Institute of Zoology Chinese Academy of Sciences BeijingChina

Nodulation is the predominant cellular defense reaction to bacterial challenges in insects. In this study, third instar larvae of Chrysomya megacephala were injected with bacteria, Escherichia coli K 12 （10^6 CFU/mL, 2μL）, immediately prior to injection of inhibitors of eicosanoid biosynthesis, which sharply reduced nodulation response. Test larvae were treated with specific inhibitors ofphospholipase A2 （dexamethasone）, cyclo- oxygenase （indomethacin, ibuprofen and piroxicam）, dual cyclo-oxygenase/lipoxygenase （phenidone） and lipoxygenase （esculetin） and these reduced nodulation except esculetin. The influence of bacteria was obvious within 2 h of injection （5 nodules/larva）, and increased to a maximum after 8 h （with 15 nodules/larva）, and then significantly reduced over 24 h （9 nodules/larva）. The inhibitory influence of dexamethasone was apparent within 2 h of injection （4 vs. 5 nodules/larva）, and nodulation was significantly reduced, compared to control, over 24 h （5 vs. 8 nodules/larva）. Increased dosages of ibuprofen, indomethacin, piroxicam and phenidone led to decreased numbers of nodules. Nodules continued to exist during the pupal stage. However, the effects of dexamethasone were reversed by treating bacteria-injected insects with an eicosanoid-precursor polyunsaturated fatty acid, arachidonic acid. These findings approved our view that eicosanoid can mediate cellular defense mechanisms in response to bacterial infections in another Dipteran insect C. rnegacephala.

关键词： bacteria Chrysomya megacephala eicosanoids Escherichia coli K12 nodulation

Effects of UV-A exposures on longevity and reproduction in Helicoverpa armigera, and on the development of its F1 generation

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Insect Science 2011年第6期18卷 697-702页

作者： Chang-Yu Zhang Jian-Yu Meng Xiao-Ping Wang fen zhu Chao-Liang Lei Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and TechnologyHuazhong Agricultural University Wuhan China

Helicoverpa armigera adults display a conspicuous positive phototactic behavior to light stimuli, and are especially sensitive to ultraviolet （UV） light. The effects of UV-A （longwave） exposures on adult longevity and reproduction in H. armigera were investigated, as well as the development of the Ft generation. Paired adults were exposed to UV-A for various time periods （0, 1, 5 and 9 h/day）, until the end of adult life. The results showed that adult longevity decreased with increasing exposure time for both sexes, and a significant decrease was observed after exposure for 5 and 9 h/day. Fecundity increased when adults were exposed for 1 and 5 h/day, and a significant difference was observed in the 5 h/day group. Oviposition rates of females in all treatments were significantly higher than in the control. Exposure to UV-A for longer periods （5 and 9 h/day） caused a decline in cumulative survival of F1 immature stages, but no significant differences were found in egg hatch, pupation and eclosion. The developmental periods of F1 larvae were significantly prolonged after exposure to UV-A for 5 and 9 h/day. UV-A radiation had no significant effects on F1 pupal period.

关键词： development Helicoverpa armigera longevity oxidative stress,reproduction UV-A

Non-invasive genetic analysis indicates low population connectivity in vulnerable Chinese gorals:concerns for segregated population management

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Zoological Research 2019年第5期40卷 439-448页

作者： Jing Yang Guo-fen zhu Jian Jiang Chang-Lin Xiang Fu-Li Gao Wei-Dong Bao College of Biological Sciences and Technology Beijing Forestry University Beijing 100083 China College of Biology and Food Science Hebei Normal University for Nationalities Chengde Hebei 067000 China Beijing Songshan National Nature Reserve Administration Beijing 102115 China Inner Mongolia Saihanwula National Nature Reserve Administration Daban Inner Mongolia 025000 China

Detailed information on the size and genetic structure of wildlife populations is critical for developing effective conservation strategies, especially for those species that have suffered population decline and fragmentation due to anthropogenic activities. In the present study, we used a non-invasive approach combining fecal pellet sampling with mitochondrial DNA and nuclear DNA microsatellite marker analysis to monitor and compare the population structure of the Chinese goral (Naemorhedus griseus) in Beijing and northeast Inner Mongolia in China. Of the 307 fecal samples confirmed to be from N. griseus, 15 individuals (nine females and six males) were found in the Beijing population and 61 individuals (37 females and 24 males) were found in the Inner Mongolian population. Among these 76 individuals, we identified eight haplotypes and 13 nucleotide polymorphic sites from mtDNA and 45 alleles from 10 microsatellite loci. Spatially structured genetic variation and a significant level of genetic differentiation were observed between the two populations. In both populations, the sex ratios were skewed toward females, indicating high reproductive potential, which is crucial for population recovery and conservation of this patchily distributed vulnerable species. We suggest that managing the two populations as evolutionarily significant units with diverse genetic backgrounds could be an effective solution for present population recovery, with the possible relocation of individuals among different groups to help ensure future goral species prosperity.

关键词： Genetic diversity Mitochondrial DNA Microsatellite marker Naemorhedus griseus Non-invasive sampling Sex ratio

Neuroimaging mechanisms of high-frequency repetitive transcranial magnetic stimulation for treatment of amnestic mild cognitive impairment:a double-blind randomized sham-controlled trial

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Neural Regeneration Research 2021年第4期16卷 707-713页

作者： Li-Qiong Yuan Qing Zeng Dan Wang Xiu-Yun Wen Yu Shi fen zhu Shang-Jie Chen Guo-Zhi Huang Department of Rehabilitation Medicine and Physiotherapy Zhujiang Hospital of Southern Medical UniversityGuangzhouGuangdong ProvinceChina Department of Rehabilitation Medicine and Physiotherapy Shenzhen Baoan Hospital of Southern Medical UniversityShenzhenGuangdong ProvinceChina Rehabilitation School of Southern Medical University GuangzhouGuangdong ProvinceChina

Individuals with amnestic mild cognitive impairment(aMCI)have a high risk of developing Alzheimer’s *** repetitive transcranial magnetic stimulation(rTMS)is considered a potentially effective treatment for cognitive impairment in patients with aMCI,the neuroimaging mechanisms are poorly ***,we performed a double-blind randomized sham-controlled trial in which rTMS was applied to the left dorsolateral prefrontal cortex of aMCI patients recruited from a community near the Third Hospital Affiliated to Sun Yat-sen University,***-four patients with aMCI were randomly assigned to receive true rTMS(treatment group,n=12,6 men and 6 women;age 65.08±4.89 years)or sham stimulation(sham group,n=12,5 men and 7 women;age 64.67±4.77 years).rTMS parameters included a stimulation frequency of 10 Hz,stimulation duration of 2 seconds,stimulation interval of 8 seconds,20 repetitions at 80%of the motor threshold,and 400 pulses per ***/sham stimulation was performed five times per week over a period of 4 consecutive *** results showed that compared with baseline,Montreal Cognitive Assessment scores were significantly increased and the value of the amplitude of low-frequency fluctuation(ALFF)was significantly increased at the end of treatment and 1 month after *** with the sham group,the ALFF values in the right inferior frontal gyrus,triangular part of the inferior frontal gyrus,right precuneus,left angular gyrus,and right supramarginal gyrus were significantly increased,and the ALFF values in the right superior frontal gyrus were significantly decreased in the treatment *** findings suggest that high-frequency rTMS can effectively improve cognitive function in aMCI patients and alter spontaneous brain activity in cognitive-related brain *** study was approved by the Ethics Committee of Shenzhen Baoan Hospital of Southern Medical University,China(approval ***20190901)on September 3,2019 and registered

关键词： Alzheimer’s disease clinical trial cognitive function cognitive impairment functional magnetic resonance imaging neurological function repetitive transcranial magnetic stimulation

Further Analysis of the Function of AtBHLH29 in Regulating the Iron Uptake Process in Arabidopsis thaliana

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Journal of Integrative Plant Biology 2006年第1期48卷 75-84页

作者： Juan Zhang Hui-fen zhu Hui Liang Kun-Fan Liu Ai-Min Zhang Hong-Qing Ling Dao-Wen Wang Institute of Genetics and Developmental Biology the Chinese Academy of Sciences Beijing 100101 China

Using T-DNA insertion and chemical mutants, two recent studies have shown that AtBHLH29, encoding a putative basic helix-loop-helix （BHLH） protein, is involved in regulating the iron uptake process in Arabidopsis thaliana. Herein, we report that RNA interference （RNAi） mutants can be used to reveal more accurately the genetic function of AtBHLH29. We compared the iron deficiency responses of seven RNAi strains that contained decreasing amounts of AtBHLH29transcripts. Under high iron conditions （50 μmol/L iron）, only in the most severe RNAi strains （R101, R111, and R119） was plant growth significantly retarded. However, these mutants could still survive and produce seeds. This suggests that the function of AtBHLH29 is beneficial, but not absolutely essential, to plant growth when iron supply is not limiting. Under low iron conditions （less than 10 μmol/L iron）, the Rlll and R119 strains died prematurely, demonstrating that AtBHLH29 is absolutely necessary for plant survival when iron supply is restricted. The transcription of AtBHLH29 was essential for the expression of AtFRO2 （encoding the ferric chelate reductase）. In contrast, the expression of AtlRT1 （encoding the high-affinity iron transporter） was not so strongly dependent upon the transcription of AtBHLH29. By transient expression, we found that the AtBHLH29-GUS fusion protein was targeted specifically to the nucleus in plant cells. Interestingly, the nuclear localization of AtBHLH29-GUS was abolished when the four consecutive arginine residues located in the basic region of the putative AtBHLH29 protein were replaced by alanine residues by mutagenesis. The implications of our findings on further studies of the mechanism underlying the function of AtBHLH29 are discussed.

关键词： Arabidopsis AtBHLH29 basic helix-loop-helix protein iron RNA interference.