Search

BACKGROUND: Coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has rapidly spread throughout the world. In this study, we aimed to identify the risk factors for severe COVID-19 to improve treatment guidelines. METHODS: A multicenter, cross-sectional study was conducted on 313 patients hospitalized with COVID-19. Patients were classified into two groups based on disease severity (nonsevere and severe) according to initial clinical presentation. Laboratory test results and epidemiological and clinical characteristics were analyzed using descriptive statistics. Univariate and multivariate logistic regression models were used to detect potential risk factors associated with severe COVID-19. RESULTS: A total of 289 patients (197 nonsevere and 92 severe cases) with a median age of 45.0 (33.0, 61.0) years were included in this study, and 53.3% (154/289) were male. Fever (192/286, 67.1%) and cough (170/289, 58.8%) were commonly observed, followed by sore throat (49/289, 17.0%). Multivariate logistic regression analysis suggested that patients who were aged ≥ 65 years (OR: 2.725, 95% confidence interval [CI]: 1.317-5.636; P = 0.007), were male (OR: 1.878, 95% CI: 1.002-3.520, P = 0.049), had comorbid diabetes (OR: 3.314, 95% CI: 1.126-9.758, P = 0.030), cough (OR: 3.427, 95% CI: 1.752-6.706, P 

A skeletonization scheme is proposed to accelerate the evaluation of scattering/radiation fields. The proposed scheme performs well for targets with multiscale feature as well as scenarios where multiple excitations are involved. Numerical experiments on targets with complex configurations are conducted to show the performance of the proposed method.

Understanding the roles of phenotypic plasticity in adaptive evolution has gained recognition for decades. Studies involving multiple taxa have shown that gene expression plasticity serves as “long-term memory” to facilitate re-adaptations to ancestral environments. Nevertheless, the general pattern and the underlying genetic basis of expression plasticity remain unclear. The transposable elements (TEs) play crucial roles in gene expression regulation and are widely distributed within the genome. Given this, we re-analyzed the transcriptomic data of chicken (Gallus gallus) generated from a reciprocal transplant experiment to examine whether expression shifts of TEs are involved in the re-adaptation process. Similar to the protein-coding genes, the plastic changes of TEs overwhelmingly exceed the genetic changes in the re-adaptation process. Further, the associated TEs co-expressed with diverse genes to perform a regulatory activity. Thus, our study supports the general function of phenotypic plasticity in adaptive evolution, and suggests a regulatory functions of TEs in this process.

Polycystic ovary syndrome (PCOS) is a disease related to reproductive endocrine abnormalities in women of reproductive age, often accompanied by metabolic diseases such as hyperandrogenemia, insulin resistance and dyslipidemia. However, the etiology and mechanism of PCOS are still unclear. In recent years, more and more studies have found that epigenetic factors play an important role in PCOS. DNA methylation is the most widely studied epigenetic modification. At present, changes of DNA methylation have been found in serum, ovarian, hypothalamus, skeletal muscle, adipose tissue of PCOS patients, and these changes are closely related to insulin resistance, lipid metabolism and follicular development of PCOS. Although the current research on DNA methylation in PCOS is not in-depth, it indicated up a good direction for future research on the etiology and mechanism of PCOS. This review discussed the relationship between DNA methylation and PCOS. It is expected to help accelerate the application of DNA methylation in the diagnosis and treatment of PCOS.

Sabia schumanniana Diels (SSD) is a plant whose stems are used in traditional folk medicine for the treatment of lumbago and arthralgia. Previous studies have revealed chemical constituents of SSD, including triterpenoids and aporphine alkaloids. Aporphine alkaloids contain a variety of active components, which might facilitate the effective treatment of lumbago and arthralgia. However, only 5-oxoaporphine (fuseine) has been discovered in SSD to date. In this study, we sought to systematically identify the aporphine alkaloids in SSD. We established a fast and reliable method for the detection and identification of these aporphine alkaloids based on ultra-high-performance liquid chromatography (UHPLC)-Q-Exactive-Orbitrap/mass spectrometry combined with parallel reaction monitoring (PRM). We separated all of the analyzed samples using a Thermo Scientific Hypersil GOLD™ aQ C18 column (100 mm × 2.1 mm, 1.9 μm). Finally, we identified a total of 70 compounds by using data such as retention times and diagnostic ions. No fewer than 69 of these SSD aporphine alkaloids have been reported here for the first time. These findings may assist in future studies concerning this plant and will ultimately contribute to the research and development of new drugs.

A new method for solving volume-surface integral equation is proposed. The four sub-blocks of the impedance matrix are compressed in a form of hierarchical semi-separable (HSS) structure by randomized low-rank decompositions. To accelerate the convergence of the iterative solution, an HSS-based preconditioner is also proposed. Numerical experiments are conducted on an on-chip power grid model to study the performance of the method. This method can be further extended to the multilevel fast multipole algorithm for solving large-scale problems.

Introduction High-quality synthesized evidence of sweet taste analgesia in neonates exists. However, Chinese databases have never been included in previous systematic reviews of sweet solutions for procedural pain. Objective To conduct a systematic review of Chinese literature evaluating analgesic effects of sweet solutions for neonates. Data sources: Wang Fang, China National Knowledge Infrastructure and Chinese Biomedical Literature Database. Data extraction and analysis: Two authors screened studies for inclusion and conducted risk of bias ratings and data extraction. A third author resolved any conflicts. Meta-analyses were performed using RevMan 5.2 software, on mean differences in pain outcomes using random effects models. Results Thirty-one trials (4999 neonates) were included; 26 trials used glucose, 4 used sucrose, and 1 trial evaluated both solutions. Sweet solutions reduced standardized mean pain scores (n = 21 studies; −1.68, 95% confidence interval −2.08, −1.27) and cry duration (n = 6 studies; −25.60, 95% confidence interval −36.47, −14.72 s) but not heart rate change (n = 7 studies; −17.64, 95% confidence interval −52.71, 17.43). No included studies cited the previously published systematic reviews of sweet solutions. Conclusions This systematic review of Chinese databases showed the same results as previously published systematic reviews. No trials included in this review cited the English systematic reviews, highlighting a parallel research agenda.

Skeletonization is employed to accelerate the multilevel fast multipole algorithm (MLFMA) solution of the method of moments matrix system arising from volume integral equations (VIEs). The acceleration is conducted in two aspects: 1) speedup of the calculation of near-field interactions of the MLFMA and 2) improvement of the iterative convergence. Numerical experiments indicate that the proposed algorithm can significantly reduce the runtime and memory usage without degrading the accuracy, in comparison with the VIE solver purely accelerated by the MLFMA. Additionally, for piecewise homogeneous complex plasmonic structures, the proposed algorithm can be more efficient and accurate than the commonly used surface integral equation solver.

In this paper, we study a fully nonlinear inverse curvature flow in sphere and hyperbolic space, and prove a non-collapsing property for this flow using maximum principle. Precisely, when ambient space is sphere, we show that upon some conditions on speed function, the radius of the largest touching interior ball is bounded below by a multiple of the reciprocal of the speed. Where ambient space is hyperbolic, we obtain an upper bound of the curvature of the largest touching interior ball for star-shaped inverse mean curvature flow.

Thermoplasmonics leads to enhanced heat generation due to the localized surface plasmon resonances. The measurement of heat generation is fundamentally a complicated task, which necessitates the development of theoretical simulation techniques. In this paper, an efficient and accurate numerical scheme is proposed for applications with complex metallic nanostructures. Light absorption and temperature increase are, respectively, obtained by solving the volume integral equation (VIE) and the steady-state heat diffusion equation through the method of moments (MoM). Previously, methods based on surface integral equations (SIEs) were utilized to obtain light absorption. However, computing light absorption from the equivalent current is as expensive as O ( N s N v ) , where Ns and Nv, respectively, denote the number of surface and volumetric unknowns. Our approach reduces the cost to O ( N v ) by using VIE. The accuracy, efficiency and capability of the proposed scheme are validated by multiple simulations. The simulations show that our proposed method is more efficient than the approach based on SIEs under comparable accuracy, especially for the case where many incidents are of interest. The simulations also indicate that the temperature profile can be tuned by several factors, such as the geometry configuration of array, beam direction, and light wavelength.

In this paper, we study the evolution of convex hypersurfaces by a fully nonlinear function of curvature minus an external force field c . We prove that the flow will preserve the convexity for any c . When c g on the initial surface, where g is the fully nonlinear function, we prove that the flow will expand the hypersurface for all time. If on initial surface M 0 the minimal principal radius of curvature r min satisfies r min > n c and minimum of the support function s satisfies s min > n c , then after a scaling the hypersurface will converge to a sphere. If c > g on the initial surface M 0 and the diameter of M 0 satisfies diam ( M 0 ) 2 n c , we show that the maximal existence time of the flow is finite.

A new method for calculation of electric field via impedance matrix of volume-surface integral equation is proposed. A set of auxiliary mesh is established and the auxiliary SWG coefficients of electric field are obtained. This method can be accelerated by fast algorithms such as MLFMA. Numerical experiments are conducted on a package interconnection to study the performance of the method.

The development of sensitive myocardial-specific cardiac biomarkers allows for detection of very small amounts of myocardial injury or necrosis. Myocardial injury (MI) as a prelude of the serious perioperative complication myocardial infarction, should be paid more attention, especially in elderly susceptible patients. Myocardial injury after abdominal surgery in elderly patients has not been described yet. The objectives of this study were to identify the incidence, predictors, characteristics and the impact of MI on outcome in elderly patients underwent abdominal surgery. Patients aged ≥ 65 who underwent abdominal surgery longer than 2 h between January 2016 and March 2017 were reviewed. Patients with peak troponin I level of 0.04 ng/ml or greater (abnormal laboratory threshold) within once-administration-period and without non-ischemia troponin elevation proof (e.g., sepsis) were assessed for characteristics and prognosis. Risk factors of MI were determined by multivariable regression. Among 285 patients with whole information, 36 patients (12.6%) suffered MI, only 2 patients (0.7%) fulfilled definition of myocardial infarction. With most of them occurred within first 7 days after surgery. Multivariable analysis showed that coronary artery disease (CAD) history [odds ratio (OR) 2.817, P = 0.015], non-laparoscopic surgery (OR 5.181, P = 0.030), blood loss ≥ 800 ml (OR 3.430, P = 0.008), non-venous maintain (OR 2.105, P = 0.047), and infection (OR 4.887, P = 0.008) as risk factors for MI. MI was associated with longer hospital stay (P = 0.006), more cardiac consultation (P = 0.011), higher infection(P = 0.016) and reoperation(P = 0.026) rate. MI is common in elderly patients who underwent abdominal surgery, while myocardial infarction is infrequent. They are both associated with risk factors and worse prognosis. MI deserves more attention especially in elderly patients. Troponin I measurement is a useful test after massive surgery, which can help risk-stratifying patients, effective preventing, prompt managing and predicting outcomes. Routine monitoring of cardiac biomarkers especially within 7 days after abdominal surgery in elderly patients is recommended.

The skeletonization accelerated multilevel fast multipole algorithm (MLFMA) in terms of surface integral equation (SIE) is extended to the method of moments (MoM) solution of volume integral equation (VIE). Boxes at the finest MLFMA level are recursively divided into smaller ones and the associated rank-deficient submatrices are approximated by skeletonization. Numerical experiments are conducted to study the performance of the proposed algorithm.

The fast algorithm which combines interpolative decomposition (ID) and the multilevel fast multipole algorithm (MLFMA) is extended to the method of moments (MoM) solution of volume integral equations (VIE) from that of surface integral equations (SIE). Boxes in the finest level in MLFMA are further divided and the rank-deficient submatrices of the near-field interactions are approximated by the data sparse representation through the ID. Numerical experiments are conducted to study the performance of the fast solver.

In this paper, a numerical scheme is presented to accurately model thermoplasmonics for arbitrarily shaped nanostructures. The volume integral equation (VIE) is utilized to calculate the light absorption, then the temperature profile is obtained by the moment of method (MoM) solution of the steady-state thermal equation. The accuracy and capability of proposed scheme are demonstrated by numerical simulations including gold rods with hemi-spherical caps and a chain of 15 gold spheres.

The fast direct solver based on skeletonization is extended to the method of moments (MoM) solution of volume integral equations (VIE). The impedance matrix is approximated by the hierarchical data sparse representation through skeletonization. The inverse matrix is then implicitly computed. Numerical experiments are conducted to study the performance of the direct solver.

Background The species-rich genus Impatiens is mainly distributed throughout much of tropical Africa, India, southwest Asia, southern China and Japan. There are more than 270 species recorded in China, most of which are restricted to the southwest. An unknown species of Impatiens was collected from Yunnan, southwest China. Results Impatiens pandurata Y. H. Tan & S. X. Yu, a new species of Balsaminaceae from Jinping County and Malipo County, Yunnan, China is similar to I. apalophylla and I. clavigera in having racemose inflorescences, 4 lateral sepals, hammer-shaped capsules and ellipsoid seeds, but differs in having leaves with oblanceolate blades aggregated at the top of the stem, 3–5-flowered racemes, a yellow lower sepal without reddish patches, yellowish flowers, and a dorsal petal with stalks at the base. Molecular phylogenetic analyses of sequences from both nuclear ribosomal and plastid genes confirm that this new species is distinct from morphologically similar species previously recorded. Conclusion With the support of careful morphological studies and phylogenetic analysis, I. pandurata is a species new to science. Electronic supplementary material The online version of this article (doi:10.1186/s40529-015-0108-4) contains supplementary material, which is available to authorized users.

The direct solver based on skeletonization consists of two stages: selecting skeletons and computing the inverse matrix. The selection of skeletons can be expensive although Huygens' principle is employed to avoid filling in the complete impedance matrix. A fast matrix filling strategy is proposed to alleviate the difficulty by making use of Taylor series. Numerical experiments indicate the proposed method can significantly accelerate the matrix filling process with no loss in accuracy.

In cancer cells, loss of E-cadherin gene expression caused dysfunction of the cell-cell junction system, triggering cancer invasion and metastasis. Therefore, E-cadherin is an important tumor-suppressor gene. To understand how E-cadherin gene expression is regulated in cancer cells, we have used E-cadherin-positive and -negative expressing cells to find out the possible up- or down regulating transcription factors in human E-cadherin regulatory sequences. Functional analysis of human E-cadherin regulatory sequences constructs indicated that AML1, Sp1, and p300 may play important roles in promoting E-cadherin expression. In addition, we found there are four HNF3-binding sites in human E-cadherin regulatory sequences. The exogenous HNF3 can enhance the E-cadherin promoter activity in metastatic breast cancer cells and the metastatic breast cancer cells stably transfected with HNF3 showed re-expression of E-cadherin. The HNF3 stable transfectants changed from mesenchymal-like into epithelial morphology. The transwell assays showed the re-expressed E-cadherin reduced cell motility of metastatic breast cancer cells. These results suggested HNF3 may play important roles in the upregulation of the E-cadherin promoter, with the consequent re-expression of E-cadherin, thus reducing the metastatic potential of breast cancer cells. These findings suggested HNF3 plays important roles in the upregulation of the E-cadherin gene and may be able to reduce the motility of metastatic breast cancer cells.

The activation of MAPK pathways in spinal cord and subsequent production of proinflammatory cytokines in glial cells contribute to the development of spinal central sensitization, the basic mechanism underlying bone cancer pain (BCP). Our previous study showed that spinal CXCL12 from astrocytes mediates BCP generation by binding to CXCR4 in both astrocyters and microglia. Here, we verified that CXCL12/CXCR4 signaling contributed to BCP through a MAPK-mediated mechanism. In naive rats, a single intrathecal administration of CXCL12 considerably induced pain hyperalgesia and phosphorylation expression of spinal MAPK members (including extracellular signal-regulated kinase, p38, and c-Jun N-terminal kinase), which could be partially prevented by pre-treatment with CXCR4 inhibitor AMD3100. This CXCL12-induced hyperalgesia was also reduced by MAPK inhibitors. In bone cancer rats, tumor cell inoculation into the tibial cavity caused prominent and persistent pain hyperalgesia, and associated with up-regulation of CXCL12 and CXCR4, activation of glial cells, phosphorylation of MAPKs, and production of proinflammatory cytokines in the spinal cord. These tumor cell inoculation-induced behavioral and neurochemical alterations were all suppressed by blocking CXCL12/CXCR4 signaling or MAPK pathways. Taken together, these results demonstrate that spinal MAPK pathways mediated CXCL12/CXCR4-induced pain hypersensitivity in bone cancer rats, which could be druggable targets for alleviating BCP and glia-derived neuroinflammation. Following tumor cell inoculation, chemokine CXCL12 from astrocytes spreads around the spinal environment, resulting in functional activation of CXCR4-expressing astrocytes and microglia. Once glia are activated, they may initiate MAPK (mitogen-activated protein kinase) pathways, and subsequently produce proinflammatory cytokines and chemokines. Among them, CXCL12 could reinforce the astrocytic and microglial activation in autocrine and paracrine manners. Such positive feedback loops sustain perseverant neuroinflammation, facilitate glial activation, and finally lead to bone cancer pain. IL = interleukin; TNF = tumor necrosis factor.

Increasing process spread has made SRAM stability a major concern in SoC integration. Previous approaches to SRAM stability testing focused on the CUT but did not address the impact of variation on testing circuitry itself. This paper presents a very simple voltage generator scheme that considers controllability and observability of testing circuitry while dealing with process variations. The proposed design can be easily tuned with a bias voltage to combat variations. Experimental results with 0.18um technology show that voltage deviation within the range of ±2% can be achieved, which greatly increases the robustness of testing circuitry against variations.

The study's aim was to assess the impact of the PET/CT on the therapeutic strategy of the patients with colorectal cancer metastasis.Fifteen patients who were suspicious of postoperative colorectal cancer metastasis were included in the study. Each patient received a positron emission tomography/computed tomography (PET/CT) after received contrast-enhanced computed tomography (ceCT). The therapeutic strategies were made before and after the PET/ CT respectively. The lesions confirmed by pathology or periodic follow up of ceCT (3 and 6 mo).Intrahepatic metastases were present in 5 of the 15 patients, total 9 lesions. The specificities of the PET/CT and ceCT were 100%. The patients with intrahepatic metastases were detected by PET/CT and ceCT with a sensitivity of 100% and 80%, respectively (p = 0.0009). Extrahepatic metastases were present in 11 of the 15 patients, total 32 lesions. The specificities of the PET/CT and ceCT were 75% and 50%, respectively. PET/ CT and ceCT were with a sensitivity of 100% and 63.6%, respectively (p = 0.0177). The therapeutic strategies were changed after received PET/CT in 6 (40%) of the 15 patients.PET/CT is superior to ceCT for the detection of the metastatic lesions of the colorectal cancer, and is a valuable tool to help select the correct therapeutic strategies.

Surface-enhanced Raman spectra of natural tissue and cancerous tissue of lung from 300 to 1700 cm(-1) were measured. In the cancerous tissue of lung, the orderly conformations of amides III and amides I of the main chains in protein such as alpha-helix, beta-corner and no rules curly were damaged seriously; conversely, the extendable vibration of skeleton C-N and skeleton C-C increased. Side chains change became complicated. In general, the content of nucleic acids increases in the cancer tissue of lung. The lengthways conformations of lecithoid chains is out-of-order in the cancerous tissue of lung compared with the natural ones.

Fetal bovine serum was treated by ozone for 1 hour and 3 hours before getting its surface-enhanced Raman spectra from 200 to 1 800 cm(-1). Treated with ozone for 1 hour, it shows a significant decrease in band intensity. Treated with ozone for 3 hours, the band intensity has a further decrease but not so obviously, which means that oxidation of ozone is short lived. Treated with ozone, the orderly conformations of main chains in protein such as alpha-helix, beta-sheet and beta-corner are damaged seriously. Aromatic side chains and C-S of Cys and Met also are damnified greatly. All this means that strong oxidation of ozone results in denaturation, conformational changes and even degradation in protein.

Impatiens tianlinensis S. X. Yu & L. J. Zhang, a new species of the Balsaminaceae from Cenwang Laoshan Mountain, Tianlin County, Guangxi Region, is described and illustrated. This species closely resembles I. apalophylla and I. clavigera var. auriculata in having racemose inflorescences, 4 lateral sepals, hammer-shaped capsules and ellipsoid seeds, but differs in having sessile glanduliferous petioles, few-flowered inflorescences, incurved spur, yellow lower sepal without reddish patches, yellowish petals and lower sepal, and acuminate dorsal petal apex. The molecular data, from nuclear ribosomal and plastid genes, as well as pollen characters also support that the species is new to science.

To summarize hemodynamic and metabolic changes during bypass, and to evaluate the bypass in liver transplantation.Fifty-four patients underwent orthotopic liver transplantation with venovenous bypass from May 2000 to May 2002. Their clinical features were analysed.SHR, MAP, CVP, CO, PaO(2), PaCO(2), serum K(+), Na(+), Ca(2+), BUN values were not significantly changed during bypass. Compared to the pre-bypass stage, pH was decreased in the post-bypass stage (P0.05), serum lactic acid value was increased in the bypass and post-bypass stage (P0.05), active clotting time was increased in the bypass stage (P0.05), serum creatinine value was increased on first postoperative day (P0.05).Venovenous bypass could improve hemodynamic and metabolic stability in the anhepatic phase, but it also could increase operation duration, liver ischemic time and cost.