1,004 research outputs found
[1-(4-Chlorophenyl)-5-hydroxy-3-phenyl-1H-pyrazol-4-yl](thiophen-2-yl)methanone
In the title compound, C20H13ClN2O2S, the chlorophenyl, phenyl and thienoyl rings are oriented at dihedral angles 17.84 (7), 53.13 (8) and 34.03 (8)°, respectively, to the central pyrazole ring. An intramolecular O—H⋯O hydrogen bond occurs. In the crystal, pairs of bifurcated O—H⋯O hydrogen bonds link molecules into inversion dimers with R
2
2(12) graph-set motifs
(E)-4-Bromo-N′-(2-hydroxy-1-naphthylmethylene)benzohydrazide
The title compound, C18H13BrN2O2, was synthesized by the reaction of 2-hydroxy-1-naphthaldehyde with 4-bromobenzohydrazide. This Schiff base molecule has an E configuration about the C=N bond and is almost planar, the dihedral angle between the mean planes through the substituted benzene ring and the naphthyl system being 6.6 (2)°. There is an intramolecular O—H⋯N hydrogen bond involving the naphthyl hydroxy substituent and the N′ atom of the hydrazide group. In the crystal structure, molecules are linked through intermolecular N—-H⋯O hydrogen bonds to form chains extending along the b direction
R\'{e}nyi Divergence Deep Mutual Learning
This paper revisits Deep Mutual Learning (DML), a simple yet effective
computing paradigm. We propose using R\'{e}nyi divergence instead of the KL
divergence, which is more flexible and tunable, to improve vanilla DML. This
modification is able to consistently improve performance over vanilla DML with
limited additional complexity. The convergence properties of the proposed
paradigm are analyzed theoretically, and Stochastic Gradient Descent with a
constant learning rate is shown to converge with -bias in the
worst case scenario for nonconvex optimization tasks. That is, learning will
reach nearby local optima but continue searching within a bounded scope, which
may help mitigate overfitting. Finally, our extensive empirical results
demonstrate the advantage of combining DML and R\'{e}nyi divergence, which
further improves generalized models
A novel edge server selection method based on combined genetic algorithm and simulated annealing algorithm
Mobile edge computing is a new paradigm which provides cloud computing capabilities at the edge of pervasive radio access networks in close proximity to users. The problem of edge server selection in mobile edge environment in terms of user’s overhead is investigated in this paper. Due to the limited resources of edge server, we firstly study the task completion probability of edge servers. Secondly, we formally model the problem of edge server selection in terms of time
latency and energy consumption. More especially, the computation overhead method for completing the task in cases of both service migration and non-migration is investigated. Then, a new optimized edge server selection algorithm, called combined Genetic algorithm and simulated Annealing algorithm for edge Server Selection (GASS) is designed. Finally, a series of experiments on a real-word data-trace are conducted to evaluate the performance of GASS. The results show that GASS can effectively minimize the overhead of the user and outperform traditional heuristic algorithms
4,6-Dimethyl-2-(naphthalen-1-yl)pyrimidine
The asymmetric unit of the title compound, C16H14N2, contains two independent molecules in which the dihedral angles between the pyrimidine and naphthaline rings are 38.20 (5) and 39.35 (5)°. Intermolecular C—H⋯π contacts and π–π stacking interactions [centroid–centroid distances = 3.766 (1) and 3.792 (1) Å] are present in the crystal structure
The Role of H. pylori
Helicobacter pylori (H. pylori, Hp) colonizes the stomachs of approximately 20%–80% of humans throughout the world. The Word Healthy Organization (WHO) classified H. pylori as a group 1 carcinogenic factor in 1994. Recently, an increasing number of studies has shown an association between H. pylori infection and various extragastric diseases. Functional dyspepsia (FD) is considered a biopsychosocial disorder with multifactorial pathogenesis, and studies have shown that infection with CagA-positive H. pylori strains could explain some of the symptoms of functional dyspepsia. Moreover, CagA-positive H. pylori strains have been shown to affect the secretion of several hormones, including 5-HT, ghrelin, dopamine, and gastrin, and altered levels of these hormones might be the cause of the psychological disorders of functional dyspepsia patients. This review describes the mutual effects of H. pylori and hormones in functional dyspepsia and provides new insight into the pathogenesis of functional dyspepsia
Complex-valued neural operator assisted soliton identification
The numerical determination of solitary states is an important topic for such
research areas as Bose-Einstein condensates, nonlinear optics, plasma physics,
etc. In this paper, we propose a data-driven approach for identifying solitons
based on dynamical solutions of real-time differential equations. Our approach
combines a machine-learning architecture called the complex-valued neural
operator (CNO) with an energy-restricted gradient optimization. The former
serves as a generalization of the traditional neural operator to the complex
domain, and constructs a smooth mapping between the initial and final states;
the latter facilitates the search for solitons by constraining the energy
space. We concretely demonstrate this approach on the quasi-one-dimensional
Bose-Einstein condensate with homogeneous and inhomogeneous nonlinearities. Our
work offers a new idea for data-driven effective modeling and studies of
solitary waves in nonlinear physical systems.Comment: 9 pages, 5 figure
Differential expression of sPLA2 following spinal cord injury and a functional role for sPLA2-IIA in mediating oligodendrocyte death
After the initial mechanical insult of spinal cord injury (SCI), secondary mediators propagate a massive loss of oligodendrocytes. We previously showed that following SCI both the total phospholipase activity and cytosolic PLA(2)-IV alpha protein expression increased. However, the expression of secreted isoforms of PLA(2) (sPLA(2)) and their possible roles in oligodendrocyte death following SCI remained unclear. Here we report that mRNAs extracted 15 min, 4 h, 1 day, or 1 month after cervical SCI show marked upregulation of sPLA(2)-IIA and IIE at 4 h after injury. In contrast, SCI induced down regulation of sPLA(2)-X, and no change in sPLA(2)-IB, IIC, V, and XIIA expression. At the lesion site, sPLA(2)-IIA and IIE expression were localized to oligodendrocytes. Recombinant human sPLA(2)-IIA (0.01, 0.1, or 2 microM) induced a dose-dependent cytotoxicity in differentiated adult oligodendrocyte precursor cells but not primary astrocytes or Schwann cells in vitro. Most importantly, pretreatment with S3319, a sPLA(2)-IIA inhibitor, before a 30 min H(2)O(2) injury (1 or 10 mM) significantly reduced oligodendrocyte cell death at 48 h. Similarly, pretreatment with S3319 before injury with IL-1 beta and TNFalpha prevented cell death and loss of oligodendrocyte processes at 72 h. Collectively, these findings suggest that sPLA(2)-IIA and IIE are increased following SCI, that increased sPLA(2)-IIA can be cytotoxic to oligodendrocytes, and that in vitro blockade of sPLA(2) can create sparing of oligodendrocytes in two distinct injury models. Therefore, sPLA(2)-IIA may be an important mediator of oligodendrocyte death and a novel target for therapeutic intervention following SCI
荆州区农村人口初发糖尿病胰岛功能的现状跟踪调查*
Objective: To study the change of islet function in patients with incipient diabetic characteristics through incipient diabetic tracking observation of the islet function in patients of Jingzhou area. Methods: Selection of 1220 cases of patients with diabetes mellitus in Jingzhou area as research object at the beginning, 12 months follow-up, the clinic after 3 months, 6 months and 12 months, all patients to detect blood sugar change, c-peptide release quantity, calculate insulin secretion index (HOMA -β) and insulin resistance index (HOMA IR), summarizes the characteristic of islet function in patients with changes. Results: ① The patients restored to basic standard blood sugar in 3 months by drug treatment, and the patient's blood glucose levels not seen obvious fluctuation after 6 months and 12 months; ② During follow-up, patients with diabetes sustained c-peptide release quantity reduction, and in three months after treatment, c-peptide release decreased obviously, and see a doctor at 6 months and 12 months after the comparison, the difference was statistically significant (P < 0.05). ③ During follow-up, insulin capacity was decreasing among patients with diabetes, within three months after the doctor had the greatest reduction, the difference was statistically significant (P < 0.05); ④ During follow-up, island hormone decreasing index, insulin resistance index continued to rise among patients with diabetes, and 6 months and 12 months, the most significant variations in 3 months (P < 0.05). Conclusion: With the extension of course, the pancreatic islet function in patients with early onset diabetes decreased gradually. It could be proved that there is a significant correlation between the two and especially seen in obvious function decline of pancreatic islets among the patients within 3 months.目的 通过对荆州区初发糖尿病患者的胰岛功能进行跟踪观察,探讨发现初发糖尿病患者胰岛功能的变化特点。方法 选取荆州区1220例初发糖尿病患者作为观察对象,跟踪随访12个月,在就诊后的3个月、6个月及12个月时,全部患者检测血糖变化、C-肽释放量,计算胰岛素分泌指数(HOMA-β)及胰岛素抵抗指数(HOMA-IR),观察总结患者的胰岛功能变化特点。结果 (1)通过药物治疗,患者血糖在3个月时基本达标,6个月及12个月时,患者的血糖水平未见明显波动;(2)随访期间,糖尿病患者C-肽释放量持续降低,且在就诊后3个月内,C-肽释放量下降明显,与就诊后6个月时及12个月时比较,差异有统计学意义(P<0.05)。(3)随访期间,糖尿病患者胰岛素放量持续降低,就诊后3个月内下降最明显,差异有统计学意义(P<0.05);(4)随访期间,糖尿病患者胰岛素分泌指数持续降低,胰岛素抵抗指数持续升高,且与6个月时和12个月时比较,3个月时变化幅度最为显著(P<0.05)。结论 随着病程的延长,初发糖尿病患者胰岛功能逐渐降低,二者具有显著相关性,且3个月内患者的胰岛功能下降最为显著
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