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关键词： MATLAB   常微分方程课程   微分方程的解析解   微分方程数值解   向量场  

摘要： 本文探讨利用MATLAB的符号运算、数值计算与绘图功能,解决常微分方程课程教学中的三个问题:求解析解及积分曲线的绘制;求方程的数值解;绘制方程的向量场。

关键词： 惠特尼   微分拓扑   嵌入定理   纤维丛   示性类  

摘要： 哈斯勒·惠特尼是20世纪美国著名的拓扑学家,1982年沃尔夫数学奖获得者。惠特尼在图论、可微映射、代数拓扑、几何积分、奇点理论领域做出了重大贡献,开创了微分流形的拓扑学,使得拓扑学的中心逐渐从欧洲转移到美国。惠特尼与中国数学家有着深刻的学术联系,因而对中国数学的发展产生了深远影响。

关键词： mouth   halitosis   sulfur compounds   L-cysteine  

摘要： Oral halitosis is characterized by a foul, unpleasant breath that emanates from the oral cavity due to local or systemic conditions. Approximately 90% of offensive odors are caused by volatile sulfur compounds (VSCs). L-cysteine, used as a test solution to control bad breath, induces the formation of VSCs and serves as a preliminary rinse. The study aim was to investigate the effectiveness of L-cysteine solution in differentiating the origin of oral halitosis using a gas chromatography apparatus. Methods: In total, 37 patients with an average age of 49.56 years were evaluated and divided into two groups: halimetry before the use of L-cysteine (n = 37) and halimetry after the use of L-cysteine (n = 37). Patients over 18 years of age, without severe systemic health impairment or infectious/contagious diseases, and who did not use medicines that influenced their breath were included. Halimetry was performed using the OralCroma (TM) device. In the halimetry before the use of L-cysteine group, 5.40%, 5.40%, and 64.86% of the patients had high levels of sulfide, methyl mercaptan, and dimethyl sulfide, respectively. After the use of L-cysteine, 48.64%, 8.10%, and 37.84% of the patients had high levels of sulfide, methyl mercaptan, and dimethyl sulfide. In this study, L-cysteine proved to be important for the assessment of oral halitosis and effective in differentiating the origin of oral halitosis;therefore, this compound could be used for the differential diagnosis of oral halitosis origin using the OralChroma (TM) device.

关键词： Actinobacteria   Biocontrol   Genome   Laccase  

摘要： The genus Streptomyces has been explored in industrial sectors due to its endurance to environmental stresses, the production of a plethora of biomolecules, the biological remediation of soils, and alleviating plant stresses. The whole genome of NGL1 and HMS4 was sequenced due to the specific laccase activity against 2,6-dimethoxyphenol (2,6-DMP) and differential plant beneficial attributes. The deduced genome of 8.85 Mbp and 7.73 Mbp in size with a G+C content of 72.03% and 72.3% was obtained for NGL1 and HMS4, respectively. A total of 8438 and 7322 protein coding genes, 155 (130 tRNA, 25 rRNA) and 145 tRNA (121 tRNA, 24 rRNA) coding genes were predicted in NGL1 and HMS4, respectively. The comparative genomics of NGL1 and HMS4 showed 185 and 162 genes encoding for carbohydrate-active enzymes, respectively. The genomic ability of these strains to encode carbohydrate-active enzymes, laccase, and diversity of BGCs, along with plant beneficial attributes to suppress the plant pathogens can be used for several industrial and agricultural applications.

关键词： Integro-differential equations   Multi-variable order   The Bernstein polynomials   Operational matrix   Collocation points  

摘要： Integro-differential equations are developed as models in enormous fields of engineering and science such as biological models, population growth, aerospace systems and industrial mathematics. In this work, we consider a general class of nonlinear fractional integro-differential equations with variable order derivative. We use the operational matrices based on the Bernstein polynomials to obtain numerical solution of this type of equations. By utilizing the operational matrices along with the Newton-Cotes collocation points, the problem under study is reduced to a system of nonlinear algebraic equations. An error estimate of the numerical solution is proved. Finally, some examples are included to show the accuracy and validity of the proposed method.

关键词： Cranial nerve palsy   Ocular motor nerve   Trochlear nerve   Abducens nerve   Magnetic resonance imaging   Cerebrospinal fluid  

摘要： Background Ocular motor nerve palsies (OMNP) frequently cause patients to present in an emergency room. In the following study, we report the differential diagnosis of OMNP by use of magnetic resonance imaging (MRI) and CSF examination as a standard. Method We performed a data analysis of N = 502 patients who presented with oculomotor, trochlear, and/or abducens nerve palsy in the emergency room of the Department of Neurology, University of Ulm, between January 2006 and December 2019. We report clinical and MRI scan findings in all patients;furthermore, the CSF of 398 patients has been analysed. Results Abducens nerve palsies were most common (45%), followed by palsies of the oculomotor (31%) (CNP III) and trochlear nerve (15%). Multiple OMNPs were seen in 9% of our cohort. The most common causes included inflammations (32.7%), space-occupying lesions, such as aneurysms or neoplasms (17.3%), diabetes mellitus (13.3%), and brainstem infarctions (11%). Still 23.4% of the patients could not be assigned to any specific cause after differential diagnostic procedures and were described as idiopathic. One of three patients with an inflammation and 39% of the patients with space-occupying lesions showed additional cranial nerve deficits. Conclusion Inflammation and space-occupying processes were the most frequent causes of OMNP, although brainstem infarctions also play a significant role, in particular in CNP III. The presence of additional CNPs increases the probability of an inflammatory or space-occupying cause.

关键词： colon   cystic fibrosis   infertility   network   rectum   transcriptome  

摘要： Tweetable abstract Cystic fibrosis: an unsupervised differential correlation network reanalysis of rectal transcriptomic data reveals promising targets for mechanistic research: FAU, SRP14 and GDI2. The value of results is highlighted by already known key role of FAU in cystic fibrosis. Background: Intestinal pathology in cystic fibrosis (CF) remains mechanistically underexplored. Aim: We hypothesized that differential correlation network analysis of expression data would reveal hub genes of CF-related disturbance in the large bowel. Materials & methods: Transcriptomes of 29 rectal tissue samples were accessed at ArrayExpress (E-GEOD-15568 by Stanke et al.). Results: We identified 279 transcript pairs differentially correlating in CF and controls, including: ESRRA and RPL18 (r(CF) = 0.55;r(controls) = -0.68;p(adj) = 1.60 x 10(-100)), SRP14 and FAU (r(CF) = -0.69;r(controls) = 0.48;p(adj) = 2.99 x 10(-90)), SRP14 and GDI2 (r(CF) = -0.34;r(controls) = 0.60;p(adj) = 1.05 x 10(-78)). The genes related to membrane protein targeting (q = 8.34 x 10(-14)) and one cluster was clearly linked to male infertility. Conclusion: FAU, SRP14 and GDI2 may be involved in a compensatory protein trafficking mechanism in CF rectum, highlighting their potential therapeutic value.

摘要： Background Sex plays a crucial role in pain processing and response to analgesic drugs. Indeed, spinal glia seems to be significant in the sexual dimorphism observed in the above effects. Recently, studies have associated oxytocin with antinociceptive effects, but these have been mainly performed in male animals;consequently, the influence of sex has been poorly explored. Methods: Using a model of spinal nociception that produces pain through activation of the spinal glia, that is, intrathecal (i.t.) lipopolysaccharide (LPS) injection, we analysed the changes in the analgesic response to i.t. oxytocin in female and male rats by behavioural (punctate mechanical hypersensitivity), electrophysiological (unitary extracellular recordings of wide dynamic range [WDR] cells) and molecular biology (real-time PCR of proinflammatory genes) experiments. Results We found that LPS-induced hypersensitivity was longer in female (>96 h) than in male (approximate to 4 h) rats. Besides, spinal oxytocin preferentially prevents the LPS-induced hypersensitivity in male rather than female rats. Indeed, LPS increases the spinal neuronal-evoked activity associated with the activation of peripheral A delta- and C-fibres and post-discharge in males, whereas only C-fibre discharge was enhanced in females. The electrophysiological data correlate with the fact that spinal oxytocin only prevented TNF-alpha and IL-1 beta synthesis in male rats. Conclusions Therefore, these data suggest that oxytocin-mediated analgesia depends on a sexual dimorphism involving activation of the spinal glia. These results reinforced the idea that different strategies are required to treat pain in men and women, and that oxytocin could be used preferentially to treat pain with a significant inflammatory component in men. Significance Statement Oxytocin is a molecule that emerges as a potent analgesic in preclinical and clinical studies. We investigated the contribution of glia to the response of oxytocin-induced analg

关键词： differentiation   flow cytometry   hematology analyzer   leukocytes  

摘要： Introduction White blood cell (WBC) differential by flow cytometry can report a six-part WBC differential and enumerate blasts. Some modern hematology analyzers are also able to provide a six-part WBC differential (including immature granulocytes). Our goal was to compare the WBC differential obtained by the Abbott Alinity hq hematology analyzer to an 8-color single-tube flow cytometry method and to manual WBC differential. Methods Samples from 144 patients were tested with Alinity hq, flow cytometry, and microscopic WBC differential. The WBC count ranged from 1.22 to 359 x 10(9)/L, and 34 samples were flagged by the analyzer for abnormal WBC morphology. Results Strong concordance was demonstrated between Alinity hq and flow cytometry for all six components of the differential, with correlation coefficients ranging from 0.86 (basophils) to 1.00 (lymphocytes). Small, clinically insignificant positive difference was observed between Alinity hq and flow cytometry for mature and total neutrophils (2.51% and 1.85%) and eosinophils (0.14%), and small negative difference for immature granulocytes (-0.65%), lymphocytes (-0.61%), and basophils (-0.21%). No bias was detected between the Alinity hq and flow cytometry monocyte counts. Alinity hq and flow cytometry results agreed with the manual differential, apart from small, clinically insignificant differences. Alinity hq nucleated red blood cell concentrations were equivalent with the manual results (r = 0.95, slope = 1.16). The percentage of blasts by flow cytometry demonstrated good correlation and agreement with the manual count (r = 0.99, slope = 1.35). Conclusion Alinity hq has produced accurate six-part WBC differential in this three-way comparison, equivalent to flow cytometry and morphological classification.

关键词： Modified multiwavelet bases   Fractional integro-differential equation   Minimal search method  

摘要： This paper improves the modified multiwavelets bases of minimal search method for the fractional integro-differential equation. First, it shows the unique solvability of the equation. And then the Legendre multiwavelets are improved and the modified multiwavelets in reproducing kernel space are obtained. Subsequently, it is established a strict theory for obtaining the e-approximate solution with minimal search method. Finally, some examples show that the modified continuous multiwavelets method is more effective and stable than the Legendre multiwavelets and other methods.