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1.
Nat Commun ; 11(1): 3311, 2020 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-32620867

RESUMO

Geoscientists mainly identify subsurface geologic features using exploration-derived seismic data. Classification or segmentation of 2D/3D seismic images commonly relies on conventional deep learning methods for image recognition. However, complex reflections of seismic waves tend to form high-dimensional and multi-scale signals, making traditional convolutional neural networks (CNNs) computationally costly. Here we propose a highly efficient and resource-saving CNN architecture (SeismicPatchNet) with topological modules and multi-scale-feature fusion units for classifying seismic data, which was discovered by an automated data-driven search strategy. The storage volume of the architecture parameters (0.73 M) is only ~2.7 MB, ~0.5% of the well-known VGG-16 architecture. SeismicPatchNet predicts nearly 18 times faster than ResNet-50 and shows an overwhelming advantage in identifying Bottom Simulating Reflection (BSR), an indicator of marine gas-hydrate resources. Saliency mapping demonstrated that our architecture captured key features well. These results suggest the prospect of end-to-end interpretation of multiple seismic datasets at extremely low computational cost.

2.
J Anesth ; 2020 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-32533332

RESUMO

PURPOSE: The aim of the study is to compare the femoral triangle (FT) and adductor canal (AC) blocks in terms of the analgesic efficacy and ambulatory outcomes in the context of multimodal analgesia following total knee arthroplasty (TKA). METHODS: Patients presenting for TKA were assigned to a preoperative ultrasound-guided single-injection FT or AC block. Combined spinal and epidural anesthesia with bupivacaine was administered for TKA. Perioperatively a multimodal analgesic regimen was applied up to 48 h after surgery. The primary outcome was the average pain score during movement in the first 24 h postoperatively. The secondary outcomes included pain scores at rest and during movement at postoperative predetermined time points, cumulative opioid consumption in oral morphine equivalents, functional mobility measured by the timed "Up and Go" (TUG) test and muscle strength in the lower extremity. RESULTS: Ninety-eight patients completed the study. Patients in the FT group had lower median pain scores during movement in the first 24 h postoperatively than those in the AC group (1.3 [1.0-3.3] vs. 3.0 [1.7-4.3]; median difference: - 1.0, adjusted 95% CI from - 1.7 to - 0.3, P = 0.010). There were significant differences in the pain scores at rest and during movement at 12 and 24 h postoperatively between the two groups (P = 0.008 and 0.005, respectively). Cumulative oral morphine equivalent consumption in the first and second 24 h postoperatively, Functional mobility reflected by the TUG test and muscle strength in the lower extremity showed no significantly statistically differences between the two groups. CONCLUSIONS: The preoperative FT block provided improved analgesic outcomes without compromising functional mobility in the context of multimodal analgesia following TKA compared with the AC block. TRIAL REGISTRATION: https://www.chictr.org.cn. Identifier: ChiCTR-INR-17012716.

4.
Artigo em Inglês | MEDLINE | ID: mdl-32433103

RESUMO

Advances in combat casualty care have improved combat survivability over the past two decades. However, these outcomes remain incompletely framed in the broader context of combat casualty outcomes over the past eighty years. We hypothesized that starting with World War II, combat survival worsened at the beginning of each new conflict but then improved over time. To evaluate long-term trends in combat casualty outcomes, monthly combat injuries and deaths during World War II, the Korean conflict, the Vietnam conflict, Operation Iraqi Freedom (OIF), and Operation Enduring Freedom (OEF) were collated. From these numbers, we calculated the monthly case fatality rate (CFR), the killed in action rate (%KIA), and the died of wounds rate (%DOW). We analyzed these metrics for significant trends during and between each conflict using linear and Loess regression. We then simulated alternate outcome scenarios by eliminating outcome variability. In this comprehensive analysis, CFR decreased over the study period in parallel with a decrease in %KIA. When examining individual conflicts, however, several unfavorable trends emerged including a spike in all fatality measures at the end of Vietnam and a rise in %DOW over the course of Korea and OIF. In comparing CFR at the beginning of each conflict to the best CFR from the prior conflict, high mortality outliers occurred in every conflict after a period of relative peace, and a clear "peacetime effect" occurred in both World War II and Vietnam. Eliminating these negative trends and the attendant preventable deaths would have reduced combat fatalities over the course of eighty years by 107,256 (39.7%). In summary, although combat mortality rates have generally improved since World War II, closer examination indicates several unfavorable trends both during and between conflicts. Identifying factors behind these trends will reveal further opportunities to improve combat casualty outcomes in the future. LEVEL OF EVIDENCE: III, Epidemiological.

5.
EClinicalMedicine ; : 100375, 2020 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-32368728

RESUMO

Background: Coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is currently a pandemic affecting over 200 countries. Many cities have established designated fever clinics to triage suspected COVID-19 patients from other patients with similar symptoms. However, given the limited availability of the nucleic acid test as well as long waiting time for both the test and radiographic examination, the quarantine or therapeutic decisions for a large number of mixed patients were often not made in time. We aimed to identify simple and quickly available laboratory biomarkers to facilitate effective triage at the fever clinics for sorting suspected COVID-19 patients from those with COVID-19-like symptoms. Methods: We collected clinical, etiological, and laboratory data of 989 patients who visited the Fever Clinic at Wuhan Union Hospital, Wuhan, China, from Jan 31 to Feb 21. Based on polymerase chain reaction (PCR) nucleic acid testing for SARS-CoV-2 infection, they were divided into two groups: SARS-CoV-2-positive patients as cases and SARS-CoV-2-negative patients as controls. We compared the clinical features and laboratory findings of the two groups, and analyzed the diagnostic performance of several laboratory parameters in predicting SARS-CoV-2 infection and made relevant comparisons to the China diagnosis guideline of having a normal or decreased number of leukocytes (≤9•5 109/L) or lymphopenia (<1•1 109/L). Findings: Normal or decreased number of leukocytes (≤9•5 109/L), lymphopenia (<1•1 109/L), eosinopenia (<0•02 109/L), and elevated hs-CRP (≥4 mg/L) were presented in 95•0%, 52•2%, 74•7% and 86•7% of COVID-19 patients, much higher than 87•2%, 28•8%, 31•3% and 45•2% of the controls, respectively. The eosinopenia produced a sensitivity of 74•7% and specificity of 68•7% for separating the two groups with the area under the curve (AUC) of 0•717. The combination of eosinopenia and elevated hs-CRP yielded a sensitivity of 67•9% and specificity of 78•2% (AUC=0•730). The addition of eosinopenia alone or the combination of eosinopenia and elevated hs-CRP into the guideline-recommended diagnostic parameters for COVID-19 improved the predictive capacity with higher than zero of both net reclassification improvement (NRI) and integrated discrimination improvement (IDI). Interpretation: The combination of eosinopenia and elevated hs-CRP can effectively triage suspected COVID-19 patients from other patients attending the fever clinic with COVID-19-like initial symptoms. This finding would be particularly useful for designing triage strategies in an epidemic region having a large number of patients with COVID-19 and other respiratory diseases while limited medical resources for nucleic acid tests and radiographic examination. Funding: This work was supported by the National Natural Science Foundation of China (NSFC) and the Major Scientific and Technological Innovation Projects of Hubei Province (MSTIP).

6.
Acta Crystallogr F Struct Biol Commun ; 76(Pt 5): 222-227, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32356524

RESUMO

The bacterial type VI secretion system (T6SS) secretes many toxic effectors to gain advantage in interbacterial competition and for eukaryotic host infection. The cognate immunity proteins of these effectors protect bacteria from their own effectors. PldB is a T6SS trans-kingdom effector in Pseudomonas aeruginosa that can infect both prokaryotic and eukaryotic cells. Three proteins, PA5086, PA5087 and PA5088, are employed to suppress the toxicity of PldB-family proteins. The structures of PA5087 and PA5088 have previously been reported, but the identification of further distinctions between these immunity proteins is needed. Here, the crystal structure of PA5086 is reported at 1.90 Šresolution. A structural comparison of the three PldB immunity proteins showed vast divergences in their electrostatic potential surfaces. This interesting phenomenon provides an explanation of the stockpiling mechanism of T6SS immunity proteins.

7.
Anal Chem ; 92(10): 7240-7248, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32323972

RESUMO

The "sample-to-answer" integration and automation of circulating tumor DNA (ctDNA)-based liquid biopsy using digital PCR (dPCR) has been hampered by the complicated operations of liquids with volumes ranging from milliliter samples to nanoliter droplets. On the basis of a "3D extensible" design paradigm proposed previously, an integrated droplet digital PCR (IddPCR) microdevice was successfully developed to automate the entire process of liquid biopsy, from the extraction of ctDNA in 2 mL of plasma using magnetic beads to the generation, amplification, and screening of over 30 000 droplets for detection. A series of reagent mixing structures, including macro-, meso-, and micromixers, was designed to enable efficient reagent handling and mixing at different volume scales. The volume thresholds of the microscale and macroscale in the IddPCR device were calculated to be 40 and 100 µL, respectively, based on the fluid dynamics and sizes of the device structures, so that different mixers can be selected according to the reagent volumes. The DNA extraction efficiency obtained on the device was determined to be ∼60%, and the on-chip ddPCR demonstrated a high correlation with an R2 of 0.9986 between the readouts and the estimations by a Poisson distribution. Finally, the IddPCR microdevice was able to detect rare tumor mutations (T790M) with an occurring frequency as low as ∼1% from 2 mL of human plasma in a "sample-to-answer" manner. This work offers a feasible solution for the automation of liquid biopsy and paves the way for its broad applications in clinics.

8.
Surg Obes Relat Dis ; 16(6): 725-731, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32276776

RESUMO

BACKGROUND: Initial development of a prominent bariatric surgery mortality risk calculator comprising cases that now account for <10% of commonly performed operations. Whether the previously highly predictive model is valid with more recent data is unknown. OBJECTIVES: To validate and improve a bariatric-surgery-specific mortality calculator with updated case mix and outcomes data. SETTING: Metabolic and Bariatric Surgery Accreditation and Quality Improvement Program-accredited bariatric surgery programs. METHODS: The Metabolic and Bariatric Accreditation and Quality Improvement Program Participant Use File from years 2015 to 2017 was used for the analysis. C-statistics were calculated with observed death as the outcome and estimated 30-day mortality risk as the only predictor and receiver operating characteristic curve was plotted. Similar analyses were repeated for each body mass index (BMI) subgroup. Backward selection logistic regression was used to investigate the potential of improving the robustness of the model. RESULTS: Patients were predominantly female (n = 446,149, 80.4%) and white (n = 409,350, 73.7%) with a mean (standard deviation) age of 45.4 (12.0) years and BMI of 44.5 (8.4) kg/m2, and the most commonly performed operation was sleeve gastrectomy (n = 338,061, 60.9%). Assessing previous model using present data, area under the curve was .7412. By BMI subgroup, area under the curve for BMI <45 kg/m2 was .7645, for BMI 45 to 60 kg/m2 was .7586, and for BMI >60 kg/m2 was .6576. DISCUSSION: The present study found that the model previously developed maintains discrimination with changing surgical procedures. Though variables in the initial calculator are helpful, additional factors should be considered when weighing risk, such as sex, previous surgery, and renal function. Future studies are needed to determine whether changes in modifiable risk factors will impact mortality rates.

10.
J Mol Model ; 26(5): 91, 2020 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-32246290

RESUMO

The mechanism of C-H bond activation of ethane was catalyzed by palladium halide cations (PdX+ (X = F, Cl, Br, H, and CH3)), which was investigated using density functional theory (DFT) at B3LYP level. The reaction mechanism was taken into account in triplet and singlet spin state potential energy surfaces. For PdF+, PdCl+, and PdBr+, the high spin states were the ground states, whereas the ground states were the low spin states in PdH+ and PdCH3+. The reaction of PdF+, PdCl+, and PdBr+ with ethane occurred via a typical "two-state reactivity" mechanism. In contrast, for PdH+ and PdCH3+, the overall reaction performed on the ground state PESs in a spin-conserving manner. The crossing points between two potential energy surfaces were observed and effectively decreased the activation barrier in PdX+/C2H6 (X = F, Cl, and Br). The minimum energy crossing points (MECP) were obtained used the algorithm in Harvey method. The natural valence electron configuration calculations were analyzed by natural bond orbital. The distribution and contribution of the front molecular orbital of the initial complexes could be further understand by the density of states. The feature of the bonding evolution in the main pathways was studied using topological analysis including localized orbital locator and atoms in molecules.

11.
Environ Res ; 186: 109527, 2020 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-32311526

RESUMO

How to reduce the risk of physical clogging is the most significant challenge during managed aquifer recharge (MAR). The prediction of occurrence and development of physical clogging has received increasing attention. In this study, chlorinated secondary wastewater (SW) was recharged into a laboratory column filled with quartz sands. The results showed that the continuous injection of reclaimed water caused a significant reduction in hydraulic conductivity by about 86% in porous media, during the 50-h injection process. The reduction was attributed to physical clogging resulting from the deposition of suspended particles with a flocculent and reticular structure, significantly increasing the surface area and the effective volume of the particle deposits. A numerical model was established based on the mass balance equations for liquid and suspended particles, coupling the particle transport-deposition model and the expressions describing the relationships between the porosity, hydraulic conductivity (K), and the concentration of deposited particles; the model was used to obtain a quantitative description of the temporal and spatial distribution of physical clogging. The bulk factor and the attachment and detachment coefficients were calibrated simultaneously. The model results provided an improved understanding of the influence degree of the three parameters on the physical clogging process. The sensitivity analysis results showed that the bulk factor had the largest sensitivity among the three parameters. In addition, a significant correlation was observed between the simulated data and the experimental data (R2 > 0.90, p < 0.01). The proposed numerical model provides a meaningful guidance tool for assessing and predicting the risk of physical clogging induced by low-density floc particles during artificial recharge with reclaimed water at a large-scale site.

12.
Sci Rep ; 10(1): 4602, 2020 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-32165676

RESUMO

In this study, two chlorophyll A/B binding protein (CAB) genes (CsCP1 and CsCP2) in tea plant were cloned. The proteins encoded by these genes belong to the external or internal antenna proteins of PS II, respectively. They may be the targets of physiological regulation for tea leaf cell PS II because they all contain multiple functional domains and modifiable sites. The CAB gene family in the tea genome consists of 25 homologous genes. We measured the expression patterns of ten genes in the CsCP1 and CsCP2 subfamily under six different stresses. CsCP1 expression was inhibited in response to 6 kinds of stress; CsCP2 expression was slightly upregulated only after cold stress and ABA treatment. However, the expression levels of CSA016997 and CSA030476 were upregulated significantly in the six stresses. The results suggested that the 10 CAB genes may have different functions in tea leaves. Moreover, changes in the expression of the 10 genes under stress appear to be related to ABA- and MeJA-dependent signalling pathways, and their responses to MeJA treatment is faster than those to ABA. In addition, we introduced our experiences for cloning the genes in the context of complex genomes.

13.
Pediatr Emerg Care ; 2020 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-32195977

RESUMO

INTRODUCTION: This study describes the experience at a level 1 pediatric trauma center before and after the centralization of prehospital trauma triage, focusing on the rate of undertriage of trauma patients. Before centralization, emergency physicians were responsible for triaging these patients with mainly physiology-based criteria; after centralization, paramedics in a communication center performed this function using the same criteria. METHODS: This retrospective study includes 10 years of pediatric trauma registry patients at our institution, 5 years before and after centralization of prehospital triage. Rates of undertriage were calculated by both the Cribari Method and by disposition from the emergency department. Logistic regression was used to assess the effect of centralization on the incidence of undertriage while adjusting for differences in case-mix. RESULTS: Over the 10-year study period, 1862 trauma activations meeting inclusion and exclusion criteria were recorded in the trauma registry: 893 patients in the precentralization and 969 in the postcentralization groups. After centralization of the triage process, there were statistically significant decreases in the rates of undertriage from 8.7% to 4.2% (adjusted odds ratio, 0.49; 95% confidence interval, 0.33-0.73) when analyzed by the Cribari Method and from 37.7% to 27.7% when analyzed by disposition from the emergency department (adjusted odds ratio, 0.66; 95% confidence interval, 0.64-0.81). This represents a reduction in undertriage by 51.7% and 26.5%, respectively. CONCLUSIONS: Centralization of prehospital trauma triage at a level 1 pediatric trauma facility significantly reduced undertriage rates. Trauma centers should consider similar processes to improve prehospital triage.

15.
Scanning ; 2020: 9591516, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32180859

RESUMO

In order to effectively reduce and retard corrosion of the power transmission and transformation equipment in Chengdu power grid and to improve power supply reliability, Q235 carbon steel material which is the most widely used metal material in power grid was selected as the targeted research object in this article. Exposure experiments were performed in urban atmospheric environment of Chengdu city in the southwest region of China. The corrosion behavior of Q235 carbon steel material was investigated at different seasons. The macro- and micromorphologies after corrosion were observed using a digital camera and scanning electron microscopy (SEM), respectively. Element distribution of the rust layer and the corrosion products was characterized by energy-dispersive spectroscopy (EDS), X-ray diffraction (XRD), and Fourier transform infrared spectroscopy (FTIR); the corrosion mechanism was also briefly analyzed.

16.
Neurosci Bull ; 36(6): 625-638, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32100248

RESUMO

Aloin is a small-molecule drug well known for its protective actions in various models of damage. Traumatic brain injury (TBI)-induced cerebral edema from secondary damage caused by disruption of the blood-brain barrier (BBB) often leads to an adverse prognosis. Since the role of aloin in maintaining the integrity of the BBB after TBI remains unclear, we explored the protective effects of aloin on the BBB using in vivo and in vitro TBI models. Adult male C57BL/6 mice underwent controlled cortical impact injury, and mouse brain capillary endothelial bEnd.3 cells underwent biaxial stretch injury, then both received aloin treatment. In the animal experiments, we found 20 mg/kg aloin to be the optimum concentration to decrease cerebral edema, decrease disruption of the BBB, and improve neurobehavioral performance after cortical impact injury. In the cellular studies, the optimum concentration of 40 µg/mL aloin reduced apoptosis and reversed the loss of tight junctions by reducing the reactive oxygen species levels and changes in mitochondrial membrane potential after stretch injury. The mechanisms may be that aloin downregulates the phosphorylation of p38 mitogen-activated protein kinase, the activation of p65 nuclear factor-kappa B, and the ratios of B cell lymphoma (Bcl)-2-associated X protein/Bcl-2 and cleaved caspase-3/caspase-3. We conclude that aloin exhibits these protective effects on the BBB after TBI through its anti-oxidative stress and anti-apoptotic properties in mouse brain capillary endothelial cells. Aloin may thus be a promising therapeutic drug for TBI.

17.
Stat Med ; 39(8): 1054-1067, 2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31957907

RESUMO

In many empirical studies, there exist rich individual studies to separately estimate causal effect of the treatment or exposure variable on the outcome variable, but incomplete confounders are adjusted in each study. Suppose we are interested in the causal effect of a treatment or exposure on an outcome variable, and we have available rich datasets that contain different confounders. How to integrate summary-level statistics from multiple individual datasets to improve causal inference has become a main challenge in data fusion. We propose a novel method in this article to identify the causal effect of a treatment or exposure on the continuous outcome. We show that the causal effect is identifiable and can be estimated by combining summary-level statistics from multiple datasets containing subsets of confounders and an external dataset only containing complete confounding information. Simulation studies indicate the unbiasedness of causal effect estimate by our method and we apply our method to a study about the effect of body mass index on fasting blood glucose.

18.
J Clin Exp Neuropsychol ; 42(3): 298-306, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31914851

RESUMO

Intertemporal decision-making refers to selection among options with distinct consequences over time. Older adults have to make important decisions regarding health care and finances among other difficult issues with different shorter- and longer-term outcomes. Patients with Alzheimer's disease (AD) or mild cognitive impairment (MCI), a potential harbinger of AD, may make suboptimal decisions in complex situations, possibly due to impaired capacity for temporal discounting. This study aimed to evaluate intertemporal preferences in AD and MCI patients compared to healthy matched controls. AD or MCI patients and healthy control (HC) patients participated in a computerized, Chinese version of the Intertemporal Choice Task in which they were asked to choose between sooner-smaller (SS) and later-larger (LL) options in now-trials and not-now-trials. The main evaluation parameter was the percentage of choices for delayed rewards(%LL). AD or MCI patients tended to choose SS options in now-trials and not now-trials with greater frequency compared to HC patients. Additionally, AD and MCI patients demonstrated significantly poorer performance in several cognitive tests compared to healthy groups, including the Mini Mental State Exam (MMSE) and other tests of memory, attention and executive function. Correlational analysis revealed that poor intertemporal decision-making was associated with executive function deficits in MCI patients. Reduced intertemporal decision-making capacity in MCI may stem from impaired executive function, possibly due to frontal-parietal circuit degeneration. The cognitive and neurophysiological deficits underlying reduce decision-making capacity in AD warrant further investigation.

19.
BMC Anesthesiol ; 20(1): 11, 2020 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-31914930

RESUMO

BACKGROUND: Few studies have investigated the effect of dexmedetomidine on postoperative nausea and vomiting (PONV) in patients underwent gynecological laparoscopic surgery. We investigated if adding dexmedetomidine to a morphine-based patient-controlled analgesia (PCA) could decrease the incidence of PONV in this high-risk patient population. METHODS: In this prospective, randomized, double-blind and placebo-controlled study, 122 patients underwent gynecological laparoscopic surgery were assigned into two groups. Patients in the dexmedetomidine group (Group Dex) received a loading dose of dexmedetomidine 0.4 µg/kg before the end of surgery, followed by morphine 0.5 mg/ml plus dexmedetomidine 1 µg/ml for postoperative i.v. PCA. Patients in the control group (Group Ctrl) received normal saline before the end of surgery, followed by morphine 0.5 mg/ml alone for postoperative i.v. PCA. PCA pump was programmed as followed: bolus dose 2 ml, lockout interval 8 min and background infusion at a rate of 1 ml/h. The primary outcome was the incidence of nausea and vomiting within the first postoperative 24 h. RESULTS: Although there were no significant differences in regard to the total incidence of PONV (41.0% vs 52.5%, P = 0.204), PONV score, time to first onset of PONV, or the need for rescue antiemetics within the first postoperative 24 h between the two groups, the incidence of nausea and total PONV during the first 2 h period was significantly lower in the Group Dex than in the Group Ctrl (9.8% vs 24.6%, P = 0.031 and 0.031, respectively). More patients in Group Dex were over sedated or had bradycardia during the PACU compared with Group Ctrl (P = 0.040 and 0.036, respectively). CONCLUSION: Our protocol in which dexmedetomidine was administered postoperatively - after a loading dose - to intravenous PCA morphine in patients undergoing gynecological laparoscopic surgery, had only early antiemetic effects, while no clinically meaningful antiemetic effect could be evidenced within the first 24 h after surgery. TRIAL REGISTRATION: Current control trial registered at Chictr.org.cn: ChiCTR1800017172. Date registered: 07/16/2018.

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