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Hydromechanical characterization of gas transport amidst uncertainty for underground nuclear explosion detection

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journal of Rock Mechanics and Geotechnical Engineering 2024年第6期16卷 2019-2032页

作者： Wenfeng Li Chelsea W.Neil j William Carey Meng Meng Luke P.Frash philip H.Stauffer Earth and Environmental Sciences Los Alamos National LaboratoryLos AlamosNM87544USA Department of Mineral Engineering New Mexico TechSocorroNM87801USA

Given the challenge of definitively discriminating between chemical and nuclear explosions using seismic methods alone,surface detection of signature noble gas radioisotopes is considered a positive identification of underground nuclear explosions(UNEs).However,the migration of signature radionuclide gases between the nuclear cavity and surface is not well understood because complex processes are involved,including the generation of complex fracture networks,reactivation of natural fractures and faults,and thermo-hydro-mechanical-chemical(THMC)coupling of radionuclide gas transport in the *** this study,we provide an experimental investigation of hydro-mechanical(HM)coupling among gas flow,stress states,rock deformation,and rock damage using a unique multi-physics triaxial direct shear rock testing *** testing system also features redundant gas pressure and flow rate measurements,well suited for parameter uncertainty *** porous tuff and tight granite samples that are relevant to historic UNE tests,we measured the Biot effective stress coefficient,rock matrix gas permeability,and fracture gas permeability at a range of pore pressure and stress *** Biot effective stress coefficient varies from 0.69 to 1 for the tuff,whose porosity averages 35.3%±0.7%,while this coefficient varies from 0.51 to 0.78 for the tight granite(porosity<1%,perhaps an underestimate).Matrix gas permeability is strongly correlated to effective stress for the granite,but not for the porous *** experiments reveal the following key engineering implications on transport of radionuclide gases post a UNE event:(1)The porous tuff shows apparent fracture dilation or compression upon stress changes,which does not necessarily change the gas permeability;(2)The granite fracture permeability shows strong stress sensitivity and is positively related to shear displacement;and(3)Hydromechanical coupling among stress states,rock damage,and gas flow appears to be

关键词： Underground nuclear explosion uncertainty quantification Radionuclide transport Biot effective stress coefficient Fracture permeability Matrix permeability

Adaptive neural network control of a 2-DOF helicopter system considering input constraints and global prescribed performance

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Science China(Information Sciences) 2024年第7期67卷 224-239页

作者： Zhijia ZHAO jiale WU Zhijie LIU We HE C.L.philip CHEN School of Mechanical and Electrical Engineering Guangzhou University School of Intelligence Science and Technology and Key Laboratory of Intelligent Bionic Unmanned Systems of Ministry of Education University of Science and Technology Beijing School of Computer Science and Engineering South China University of Technology Pazhou Lab

In this study, an adaptive neural network(NN) control is proposed for nonlinear two-degree-offreedom(2-DOF) helicopter systems considering the input constraints and global prescribed ***, radial basis function NN(RBFNN) is employed to estimate the unknown dynamics of the helicopter system. Second, a smooth nonaffine function is exploited to approximate and address nonlinear constraint functions. Subsequently, a new prescribed function is proposed, and an original constrained error is transformed into an equivalent unconstrained error using the error transformation and barrier function transformation methods. The analysis of the established Lyapunov function proves that the controlled system is globally uniformly bounded. Finally, the simulation and experimental results on a constructed Quanser's test platform verify the rationality and feasibility of the proposed control.

关键词： adaptive NN control 2-DOF helicopter global prescribed performance input constraints

Distinct vibrational signatures and complex phase behavior in metallic oxygen

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Matter and Radiation at Extremes 2024年第2期9卷 4-11页

作者： philip Dalladay-Simpson Bartomeu Monserrat Li Zhang Federico Gorelli Center for High Pressure Science Technology Advanced Research 1690 Cailun RoadShanghai 201203China Department of Materials Science and Metallurgy University of Cambridge27 Charles Babbage RoadCambridge CB3 OFSUnited Kingdom Cavendish Laboratory University of CambridgeJ.J.Thomson AvenueCambridge CB3 OHEUnited Kingdom Istituto Nazionale di Ottica Consiglio Nazionale delle Ricerche(CNR-INO)50125 FlorenceItaly Shanghai Advanced Research in Physical Sciences(SHARPS) ShanghaiChina

Evidence for metallization in dense oxygen has been reported for over 30 years[Desgreniers et al.,***.94,1117(1990)]at a now routinely accessible 95 GPa[Shimizu et al.,Nature 393,767(1998)].However,despite the longevity of this result and the technological advances since,the nature of the metallic phase remains poorly constrained[Akahama et al.,***.74,4690(1995);Goncharov et al.,***.B 68,224108(2003);Ma,***.B 76,064101(2007);and Weck et al.,***.102,255503(2009)].In this work,through Raman spectroscopy,we report the distinct vibrational characteristics of metallicζ-O_(2) from 85 to 225 *** comparison with numerical simulations,weﬁnd reasonable agreement with the candidate structure up to about 150 *** higher pressures,the C2/mstructure is found to be unstable and incompatible with experimental *** candidate structures,and Ci,with C2/m C2/conly two molecules in the primitive unit cell,are found to be stable and more compatible with measurements above 175 GPa,indicative of the dissociation of(O_(2))4 ***,we report and discuss a strong hysteresis and metastability with the precursory phaseϵ-O_(2).Theseﬁndings will reinvigorate experimental and theoretical work into the dense oxygen system,which will have importance for oxygen-bearing chemistry,prevalent in the deep Earth,as well as fundamental physics.

关键词： metallic phase vibrational

Lipid nanoparticles deliver mRNA to the blood-brain barrier

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Nano Research 2024年第10期17卷 9126-9134页

作者： Yanina Kuzminich Avraham Shakked Randi Calkins Sebastian Rudden Camille jones jessie Doan Bora jang Elisa Schrader Echeverri Ryan Zenhausern Liming Lian David Loughrey Hannah E.Peck Rachelle Wiese Dorothy Koveal philip j.Santangelo james E.Dahlman George C.Woodruff School of Mechanical Engineering Georgia Institute of TechnologyAtlantaGA 30332USA Parker H.Petit Institute for Bioengineering and Biosciences Georgia Institute of TechnologyAtlantaGA 30332USA Wallace H.Coulter Department of Biomedical Engineering Emory University School of Medicine and Georgia Institute of TechnologyAtlantaGA 30332USA

Lipid nanoparticles(LNPs)have delivered RNA to hepatocytes in patients after intravenous *** clinical data support efforts to design LNPs that transfect cells in the central nervous system(CNS).However,delivery to the CNS has been difficult,in large part because quantifying on-target delivery alongside common off-target cell types in adult mice remains *** we report methods to isolate different cell types from the CNS,and subsequently present mRNA delivery readouts using a liver-detargeted *** data suggest that LNPs without targeting ligands can transfect cerebral endothelial cells in mice after intravenous *** the difficulty of crossing the blood-brain barrier,they also underscore the value of quantifying delivery in the CNS with cell-type resolution instead of whole-tissue resolution.

关键词： lipid nanoparticle mRNA nanomedicine central nervous system blood-brain barrier

The impact of COVID-19 on clinical outcomes of burn patients

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Burns & Trauma 2023年第1期11卷 792-799页

作者： Elliot T.Walters Alen Palackic Camila Franco-Mesa Nikhil R.Shah Michael j.erickson Steven E.Wolf Department of Surgery University of Texas Medical Branch301 UniversityGalvestonTXUSA Division of Plastic Aesthetic and Reconstructive SurgeryDepartment of SurgeryMedical University of GrazGrazAustria

Background:Multiple studies have shown the SARS-CoV-2 virus(COVID-19)to be associated with deleterious outcomes in a wide range of *** impact of COVID-19 has not been well investigated among burned *** suspect that patients will have worsened respiratory and thrombotic complications,ultimately leading to increased *** objective of this study is to determine the impact a concurrent infection of COVID-19 has on clinical outcomes after a burn ***:This is a retrospective,propensity matched,cohort *** examined a de-identified database of electronic medical records of over 75 million patients across 75 health care associations in the United States for patients treated for thermal burns from 1 january 2020,to 31 july 2021,and those who also were diagnosed with COVID-19 infection within one day before or after injury based on International Classification of Disease,tenth revision(ICD-10)*** participants included adults who were treated for a burn injury during the study ***:We included 736 patients with burn injury and concomitant COVID-19 infection matched to 736 patients with burn injury and no concurrent COVID-19 infection(total 1472 patients,mean age 36.3±24.3).We found no significant increase in mortality observed for patients with concurrent COVID-19(OR 1.203,95%CI 0.517-2.803;p=0.6675).We did observe significant increase in infections(OR 3.537,95%CI 2.798-4.471;p=0.0001),thrombotic complications(OR 2.342,95%CI 1.351-4.058;p=0.0018),as was the incidence of hypertrophic scarring(OR 3.368,95%CI 2.326-4.877;p=0.0001).Conclusions:We observed that concurrent COVID-19 infection was associated with an increase in infections,thrombosis and hypertrophic scarring but no increase in mortality in our cohort of burn patients.

关键词： COVID-19 infection mortality burn thrombosis scarring

Boosting Adaptive Weighted Broad Learning System for Multi-Label Learning

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IEEE/CAA journal of Automatica Sinica 2024年第11期11卷 2204-2219页

作者： Yuanxin Lin Zhiwen Yu Kaixiang Yang Ziwei Fan C.L.philip Chen the School of Computer Science and Engineering in South China University of Technology IEEE the Pengcheng Laboratory

Multi-label classification is a challenging problem that has attracted significant attention from researchers, particularly in the domain of image and text attribute annotation. However, multi-label datasets are prone to serious intra-class and inter-class imbalance problems, which can significantly degrade the classification performance. To address the above issues, we propose the multi-label weighted broad learning system(MLW-BLS) from the perspective of label imbalance weighting and label correlation mining. Further, we propose the multi-label adaptive weighted broad learning system(MLAW-BLS) to adaptively adjust the specific weights and values of labels of MLW-BLS and construct an efficient imbalanced classifier set. Extensive experiments are conducted on various datasets to evaluate the effectiveness of the proposed model, and the results demonstrate its superiority over other advanced approaches.

关键词： Learning systems Adaptation models Correlation Adaptive systems Annotations Boosting Classification algorithms Broad learning system label correlation mining label imbalance weighting multi-label imbalance CLASSIFICATION ENSEMBLE

The Effects of Zinc Sulfate on the in Vitro Digestibility of Feeds in Cervids

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Open journal of Animal Sciences 2024年第3期14卷 157-167页

作者： Reese j. Thibodeaux philip M. Urso Stanley F. Kelley Marcy M. Beverly Chris R. Stewart Ian C. Dunn Gentech Diagnostics Dallas Texas USA Department of Animal Science South Dakota State University Brookings South Dakota USA School of Agricultural Sciences Sam Houston State University Huntsville Texas USA 3-S Texas Outdoors/3-S Whitetails Bedias Texas USA

The captive white-tailed deer industry has an estimated impact of 1.6 billion USD in the state of Texas alone. However, nutritional requirements for cervids are determined through research based on sheep and goats. The objective of this study was to determine the effects of zinc on differences in dry matter digestibility in vitro for white-tailed does (Odocoileus virginianus). Deer (n = 2) were ethically harvested, rumens were collected, and placed into a cooler containing warm water. Rumen contents were agitated, and fluid was filtered using cheese cloth while applying CO2. Fluid was placed into four separate incubator jars with filter bags containing a 1:1 alfalfa to coastal hay blend. Zinc doses of 0.073 mg/kg/d equivalents were added to two of the jars ( Zn), and the additional two jars received 0.00 mg/kg/d (CON). Following 48 h of incubation, in vitro true digestibility (IVTD) showed no significant differences between the control and the treatment groups. Average dry matter digested in vitro was 91.87% and 95.13%, respectively. There were no differences detected in ADF, NDF, IVTD, or OM between the treatment groups. While no detectable differences were observed in this study, this methodology did prove to be viable and functional for microbial digestion in vitro. This study can be replicated with multiple experimental units to confirm the observations of increased digestibility. Formal nutritional guidelines can be created to allow for more efficient feeding of cervids thereby reducing feed costs and continuing the growth of the captive deer industry.

关键词： Zinc IVDMD In Vitro Cervids

Bone targeted therapies for the prevention of skeletal morbidity in men with prostate cancer

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Asian journal of Andrology 2014年第3期16卷 341-347页

作者： philip j Saylor Division of Hematology-Oncology Massachusetts General Hospital Cancer Center Boston Massachusetts USA.

Men with prostate cancer suffer substantially from bone-related complications. Androgen deprivation therapy itself is a cause of loss of bone mineral density and is associated with an increased incidence of osteoporotic fractures. In advanced disease, bone is by far the most common site of metastasis. Complications of bone metastases prominently include pain and the potential for skeletal events such as spinal cord compression and pathologic fractures. Elevated osteoclast activity is an important aspect of the pathophysiology of both treatment-related osteoporosis and skeletal complications due to metastases. The osteoclast is therefore a therapeutic target. Denosumab is a fully human monoclonal antibody to receptor activator of nuclear factor-K-B ligand that was designed to potently inhibit osteoclast activity and is the central focus of this review. Bisphosphonates, radiopharmaceuticals and systemically-active hormonal agents such as abiraterone acetate and enzalutamide have each been shown to improve skeletal morbidity in specific clinical situations. Denosumab is the only agent that has been shown to prevent osteoporotic fractures in men receiving androgen deprivation therapy and at elevated risk for fracture. It has also demonstrated superiority to the potent bisphosphonate zoledronic acid for the prevention of skeletal-related events in men with castration-resistant prostate cancer metastatic to bone. Efficacy and toxicity data will be discussed.

关键词： denosumab osteoporosis osteopenia osteoclast RANK (receptor activator of nuclear factor-kappa B) skeletal-relatedevents

Adding Value to Crop Production Systems by Integrating Forage Cover Crop Grazing

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American journal of Plant Sciences 2024年第3期15卷 180-192页

作者： Robert B. Mitchell Daren D. Redfearn Kenneth P. Vogel Terry j. Klopfenstein Galen erickson P. Stephen Baenziger Bruce E. Anderson Mary E. Drewnoski jay Parsons Steven D. Masterson Marty R. Schmer Virginia L. jin USDA-ARS Wheat Sorghum and Forage Research Unit University of Nebraska-Lincoln Lincoln NE USA Department of Agronomy and Horticulture University of Nebraska-Lincoln Lincoln NE USA Department of Animal Science University of Nebraska-Lincoln Lincoln NE USA Department of Agricultural Economics University of Nebraska-Lincoln Lincoln NE USA USDA-ARS Agroecosystem Management Research Unit University of Nebraska-Lincoln Lincoln NE USA

In addition to their value as cereal grains, wheat (Triticum aestivum L.) and triticale (× Triticosecale Wittmack) are important cool-season annual forages and cover crops. Yearling steer (Bos taurus) performance was compared in the spring following autumn establishment as for age cover crops after soybean [Glycine max (L.) Merr.] grain harvest. Replicated pastures (0.4 ha) were no-till seeded in three consecutive years into soybean stubble in autumn, fertilized, and grazed the following spring near Ithaca, NE, USA. Each pasture (n = 3) was continuously stocked in spring with four yearling steers (380 ± 38 kg) for 17, 32, and 28 d in 2005, 2006, and 2007, respectively. In 2005, average daily gain (ADG) for steers grazing triticale exceeded the ADG for wheat by 0.31 kghd-1d-1. In 2006, wheat ADG exceeded that for triticale by 0.12 kghd-1d-1. In 2007, steers grazing wheat lost weight, while steers grazing triticale gained 0.20 kghd-1d-1. Based on the 3-year average animal gains valued at $1.32 kg-1, mean net return ($ ha-1 yr-1) was $62.15 for triticale and $22.55 for wheat. Since these grazed cover crops provide ecosystem services in addition to forage, grazing could be viewed as a mechanism for recovering costs and adds additional value to the system. Based on this 3-year grazing trial, triticale was superior to wheat and likely will provide the most stable beef yearling performance across years with variable weather for the western Cornbelt USA.

关键词： Cover crops Soybean Triticale Wheat