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The Use of Geophysical Methods to Discriminate between Brine Layers and Freshwater Taliks in Permafrost Regions

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冰川冻土 2004年第S1期26卷 301-309页

作者： Kenji Yoshikawa Vladimir Romanovsky Nataria Duxbury jerry brown Alexandre Tsapin Water and Environmental Research Center Institute of Northern Engineering University of Alaska Fairbanks PO Box 755860 Fairbanks AK 99775-5860 USA Geophysical Institute University of Alaska Fairbanks 903 Koyukuk Drive P.O. Box 757320 Fairbanks AK 99775-7320 USA Jet Propulsion Laboratory 4800 Oak Grove Drive MS 183-301 Pasadena CA 91109 USA International Permafrost Association P.O. Box 7 Woods Hole MA 02543 USA

Direct current resistivity and ground penetrating radar surveys were employed to obtain the value of the resistivity and dielectric constant in the brine near the Barrow, Alaska. The geophysical surveys were undertaken together with the permafrost drilling program for the measuring of the ground temperature regime and for the core sampling. The sampled cores were measured for their physical and chemical properties in the laboratory under different temperature conditions ((-60) to (20) ℃). Laboratory results support field observations and led to the development of a technique for distinguishing freshwater taliks and brine layers in permafrost. These methods were also employed in freshwater taliks near Council, Alaska. The electrical resistivity is a powerful and sensitive parameter for brine detection. However, the resistivity is a less sensitive indicator of the soil type or water content under highly saline conditions. High frequency dielectric constant is an ideal second parameter for the indication of the soil type, liquid water content and other physical properties. The imaginary part of the dielectric constant and resistivity have a significant dependence upon salinity, i.e. upon freezing temperature. The ground temperature regime and the freezing point of the brine layer are important parameters for studying the electric properties of permafrost terrain.

关键词： geophysical method resistivity and dielectric constant talik Barrow,Alaska

Role of N-formyl peptide receptor 2 in germinal matrix hemorrhage:an intrinsic review of a hematoma resolving pathway

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Neural Regeneration Research 2024年第2期19卷 350-354页

作者： jerry Flores Jiping Tang Department of Physiology&Pharmacology Loma Linda University School of MedicineLoma LindaCAUSA

Germinal matrix hemorrhage is one of the leading causes of morbidity,mortality,and acquired infantile hydrocephalus in preterm infants in the United States,with little progress made in its clinical *** clots have been shown to elicit secondary brain injury after germinal matrix hemorrhage,by disrupting normal cerebrospinal fluid circulation and absorption after germinal matrix hemorrhage causing post-hemorrhagic hydrocephalus *** evidence suggests that rapid hematoma resolution is necessary to improve neurological outcomes after hemorrhagic *** articles have demonstrated the beneficial effects of stimulating the polarization of microglia cells into the M2 phenotype,as it has been suggested that they play an essential role in the rapid phagocytosis of the blood clot after hemorrhagic models of stroke.N-formyl peptide receptor 2(FPR2),a G-protein-coupled receptor,has been shown to be neuroprotective after ***2 activation has been associated with the upregulation of phagocytic macrophage clearance,yet its mechanism has not been fully *** literature suggests that FPR2 may play a role in the stimulation of scavenger receptor *** receptor CD36 plays a vital role in microglia phagocytic blood clot clearance after germinal matrix ***2 has been shown to phosphorylate extracellular-signal-regulated kinase 1/2(ERK1/2),which then promotes the transcription of the dual-specificity protein phosphatase 1(DUSP1)*** this review,we present an intrinsic outline of the main components involved in FPR2 stimulation and hematoma resolution after germinal matrix hemorrhage.

关键词： AnxA1 FPR2 GMH hematoma resolution hemorrhagic stroke M1 M2 microglia polarization microglia phagocytosis

International Permafrost Association

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Episodes 2005年第4期28卷 301-302页

作者： Dr. jerry brown Dr. Hanne H. Christiansen President International Permafrost Association P.O. Box 7 Woods Hole MA 02543 USA International Permafrost Association Secretariat The University Centre in Svalbard （ UNIS）P.O Box 1569171 Longyearbyen NOR WAY

The International Permafrost Association, founded in 1983, has as its objectives to foster the dissemination of knowledge concerning permafrost and to promote cooperation among persons and national and international organisations engaged in scientific investigation and engineering work related to permafrost and seasonally frozen ground. The IPA became an Affiliated Organisation of the International Union of Geological Sciences （IUGS） in July 1989.

关键词：国际冻土会议学术交流行业管理气候变化冻土工程

IDS-INT:Intrusion detection system using transformer-based transfer learning for imbalanced network traffic

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Digital Communications and Networks 2024年第1期10卷 190-204页

作者： Farhan Ullah Shamsher Ullah Gautam Srivastava jerry Chun-Wei Lin School of Software Northwestern Polytechnical UniversityXian710072ShaanxiChina Knowledge Unit of Systems and Technology University of Management and TechnologySialkot 51040Pakistan Department of Math and Computer Science Brandon UniversityBrandonMB R7A 6A9Canada Department of Computer Science and Math Lebanese American UniversityBeirut1102Lebanon Western Norway University of Applied Sciences BergenNorway Research Centre for Interneural Computing China Medical UniversityTaichungTaiwanChina

A network intrusion detection system is critical for cyber security against llegitimate *** terms of feature perspectives,network traffic may include a variety of elements such as attack reference,attack type,a subcategory of attack,host information,malicious scripts,*** terms of network perspectives,network traffic may contain an imbalanced number of harmful attacks when compared to normal *** is challenging to identify a specific attack due to complex features and data imbalance *** address these issues,this paper proposes an Intrusion Detection System using transformer-based transfer learning for Imbalanced Network Traffic(IDS-INT).IDS-INT uses transformer-based transfer learning to learn feature interactions in both network feature representation and imbalanced ***,detailed information about each type of attack is gathered from network interaction descriptions,which include network nodes,attack type,reference,host information,***,the transformer-based transfer learning approach is developed to learn detailed feature representation using their semantic ***,the Synthetic Minority Oversampling Technique(SMOTE)is implemented to balance abnormal traffic and detect minority ***,the Convolution Neural Network(CNN)model is designed to extract deep features from the balanced network ***,the hybrid approach of the CNN-Long Short-Term Memory(CNN-LSTM)model is developed to detect different types of attacks from the deep *** experiments are conducted to test the proposed approach using three standard datasets,i.e.,UNsWNB15,CIC-IDS2017,and *** explainable AI approach is implemented to interpret the proposed method and develop a trustable model.

关键词： Network intrusion detection Transfer learning Features extraction Imbalance data Explainable AI Cybersecurity

Aerodynamics of a Tandem-Bladed Axial Compressor Rotor under Circumferential Distortion at Different Rotational Speeds

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Journal of Thermal Science 2024年第4期33卷 1340-1356页

作者： Amit KUMAR jerry T.JOHN A.M.PRADEEP R.A.DAKKERMANS Dragan KOZULOVIC Department of Aerospace Engineering Indian Institute of Technology BombayMumbai400076India Department of Automotive and Aeronautical Engineering Hamburg University of Applied Sciences20099HamburgGermany Institute of Jet Propulsion Bundeswehr University Munich85577NeubibergGermany

For most aircraft engines,inflow distortion is *** distortion is known to degrade the aerodynamic performance and stable operating limits of a *** rotor configuration is an arrangement that effectively controls the growth of the boundary layer over the suction surface of the ***,a higher total pressure rise can be achieved through this unconventional design approach involving the splitting of the blade into forward and aft *** is expected that the effect of inlet flow distortion would be more severe for a tandem-rotor design due to the greater flow turning inherent in such ***,this aspect needs to be thoroughly *** present study discusses the effect of circumferential distortion on the tandem-rotor at different rotational ***-annulus RANS simulations using ANSYS CFX are used in the present *** performance of the rotor at a particular flow coefficient and different rotational speeds is *** total pressure and efficiency are observed to drop at lower mass flow rates under the influence of circumferential *** loss region in each blade passage is mainly associated with the blade wake,tip leakage vortex,secondary flow,and boundary ***,their contribution varies from passage to passage,particularly in the distorted *** the lower span,the wake width is found to be higher than that at a higher *** to the redistribution of the mass flow,the circumferential extent reduces at a higher *** the undistorted sector,the strength of the tip leakage vortex is significantly higher at the design rotational speed than at lower *** distortion near the tip region promotes an early vortex breakdown even at the design operating *** adversely affects the total pressure,efficiency,and stall *** clean flow conditions,this phenomenon is only observed near the stall *** the design operating condition,the breakdown of the forward rotor tip l

关键词： tandem rotor circumferential distortion loss tip leakage vortex vortex breakdown diffusion factor aerodynamics of compressor blade

Analysis of Deep Ritz Methods for Semilinear Elliptic Equations

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NUMERICAL MATHEMATICS-THEORY METHODS AND APPLICATIONS 2024年第1期17卷 181-209页

作者： Chen, Mo Jiao, Yuling Lu, Xiliang Song, Pengcheng Wang, Fengru Yang, jerry Zhijian Wuhan Univ Sch Math & Stat 299 Ba Yi Rd Wuhan 430072 Peoples R China Wuhan Univ Hubei Key Lab Computat Sci 299 Ba Yi Rd Wuhan 430072 Peoples R China

In this paper, we propose a method for solving semilinear elliptical equations using a ResNet with ReLU2 activations. Firstly, we present a comprehensive formulation based on the penalized variational form of the elliptical equations. We then apply the Deep Ritz Method, which works for a wide range of equations. We obtain an upper bound on the errors between the acquired solutions and the true solutions in terms of the depth D, width W of the ReLU2 ResNet, and the number of training samples n. Our simulation results demonstrate that our method can effectively overcome the curse of dimensionality and validate the theoretical results.

关键词： Semilinear elliptic equations Deep Ritz method ReLU2 ResNet convergence rate PARTIAL-DIFFERENTIAL-EQUATIONS INFORMED NEURAL-NETWORKS MONTE-CARLO NUMERICAL-SOLUTION CONVERGENCE ALGORITHM

Helicobacter Pylori Infections in Peptic Ulcer Perforations: A Retrospective Analysis in Two Referral Hospitals in Douala, Cameroon

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Surgical Science 2020年第10期11卷 298-311页

作者： Francois Adrien Morel Bokalli Chi Fru McWright jerry brown Njoh Aseneh Takere Maseoli Mbachan Ngomba Divine Mokake Jules Clément Assob Nguedia Marcelin Ngowe Ngowe Department of Medicine Faculty of Health Sciences University of Buea Buea Cameroon Laquintinie Hospital Douala Cameroon Department of Surgery Faculty of Health Sciences University of Buea Buea Cameroon Department of Biomedical Sciences Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Department of Surgery Faculty of Medicine and Pharmaceutical Sciences University of Douala Douala Cameroon

Background: Perforations are major complications of peptic ulcer disease and surgical emergencies with important mortality and morbidity. Helicobacter pylori (H. pylori) has been identified as one of the commonest factors associated with peptic ulcer disease. However, little is known about its implication in cases of perforations in Cameroon. We aimed to determine the frequency of Helicobacter pylori infections in cases of perforated peptic ulcers, describe clinical features and outcomes of these cases in Cameroon. Method: A hospital-based retrospective cross-sectional study was conducted through the review of patients’ records admitted for peptic ulcer perforations in Laquintinie and Douala General Hospitals over a period of 5 years (January 2014 - December 2018). We defined H. pylori infection as;positive result on tissue biopsy at time of surgery. We used SPSS version 23.0 to analyse data and set an alpha value at P = 0.05. Results: We reviewed 115 cases of peptic ulcer perforation, with a mean age of 40 years and sex ratio (M:F) of 5:1. All patients underwent emergency laparotomy, 48 (41%) cases had a biopsy report and the prevalence of H. pylori infection in these cases was 47.9 %. Smoking, alcohol consumption and Non-Steroidal Anti-inflammatory Drugs (NSAIDs) use, were not associated with peptic ulcer perforation. The morbidity was at 43.7% and mortality at 14%. Mortality was increasing with a higher Mannheim Peritonitis Index score (OR: 23.51, 95% CI: 4.197 - 143.003, P-value: 0.000). Conclusion: We observed a high prevalence of H. pylori infection in patients with peptic ulcer perforations. We recommend systematic H. pylori screening in cases of perforations and that larger studies should be carried out to evaluate the association of H. pylori infection with peptic ulcer perforation in Sub-Saharan Africa.

关键词： Perforated Peptic Ulcers Helicobacter pylori Infections Clinical Features Outcome

Responses of growth performance,antioxidant function,small intestinal morphology and mRNA expression of jejunal tight junction protein to dietary iron in yellow-feathered broilers

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Journal of Integrative Agriculture 2024年第4期23卷 1329-1337页

作者： Kaiwen Lei Hao Wu jerry W Spears Xi Lin Xi Wang Xue Bai Yanling Huang Key Laboratory of Animal Science of State Ethnic Affairs Commission Southwest Minzu UniversityChengdu 610041China Key Laboratory of Qinghai-Tibetan Plateau Animal Genetic Resource Reservation and Utilization Southwest Minzu UniversityChengdu 610041China Department of Animal Science North Carolina State UniversityRaleighNC 27695-7621USA

This study aimed to investigate the dose-effect of iron on growth performance,antioxidant *** morphology,and mRNA expression of jejunal tight junction protein in 1-to21-d-old yellow-feathered broilers.A total of 7201-d-old yellow-feathered maleb roilers were allocated to 9 treatments with 8 replicate cages of 10 birds per *** dietary treatments were consisted of a basal diet(contained 79.6 mg Fe kg^(-1))supplemented with 0,20,40,60,80,160,320,640,and 1,280 mg Fe kg^(-1)in the form of FeSO_(4)·7H_(2)*** with the birds in the control group,birds supplemented with 20mg Fe kg^(-1)had higher average daily gain(ADG)(P<0.0001).Adding 640 and 1,280 mg Fe kg^(-1)significantly decreased ADG(P<0.0001)and average daily feed intake(ADFI)(P<0.0001)compared with supplementation of 20mg Fe kg^(-1).Malondialdehyde(MDA)concentration in plasma and duodenum increased linearly(P<0.0001),but MDA concentration in liver and jejunum increased linearly(P<0.05)or quadratically(P<0.05)with increased dietary Fe *** villus height(VH)in duodenum and jejunum,and the ratio of villus height to crypt depth(V/C)in duodenum decreased linearly(P?0.05)as dietary *** dietary Fe increased,the jejunal relative mRNA abundance of claudin-1 decreased linearly(P=0.001),but the jejunal relative mRNA abundance of zona occludens-1(ZO-1)and occludin decreased linearly(P?0.05)or quadratically(P?0.05).Compared with the supplementation of 20 mg Fe kg^(-1),the supplementation of640 mg Fe kg^(-1)or higher increased(P?0.05)MDA concentrations in plasma,duodenum,and jejunum,decreased VH in the duodenum and jejunum,and the addition of 1,280 mg Fe kg^(-1)reduced(P?0.05)the jejunal tight junction protein(claudin-1,ZO-1,occludin)mRNA *** summary,640 mg of supplemental Fe kg^(-1)or greater was associated with decreased growth performance,increased oxidative stress,disrupted intestinal morphology,and reduced mRNA expression of jejunal tight junction protein.

关键词： iron yellow-feathered broiler antioxidant function intestinal morphology tight junction protein

Chemical Determination of Base Status Metals in Soil Sediments and Particulate Matter in Wellington Industrial Estate Location

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Open Journal of Applied Sciences 2024年第5期14卷 1338-1352页

作者： Richard Tamba Simbo jerry Yeke Paye Fayia Francis Nyuma Department of Chemistry School of Basic Sciences Njala University Freetown Sierra Leone Department of Science and Mathematics College of Arts and Sciences William V.S. Tubman University Harper Liberia Department of Fisheries and Science Thomas J.R Faulkner College of Science and Technology University of Liberia Monrovia Liberia

This research study explored the levels of base status metals in soil sediments and particulate matter in the wellington industrial estate location;the main objectives were to: 1) determine sodium and potassium, 2) determine calcium and magnesium, 3) determine available iron. The following hypotheses were put forward;H0a: there is no significant difference in the concentration levels between Ca and Mg in the study area, H1a: there is significant difference in the concentration levels between Ca and Mg in the study area, H0b: there is no significant difference in the concentration levels between Na and K in the study area, H1b: there is significant difference in the concentration levels between Na and K in the study area. Six locations were used to collect samples with the aid of scoop and gravel free auger (at varying depths of 0 - 5 cm and 5 - 10 cm) which are Wellington Industrial Estate Area 1 (WIEL 1), (WIEL 2), (WIEL 3), (WIEL 4), (WIEL 5), (WIEL 6);the samples were given laboratory treatment. Flame photometer, EDTA, and Spectrophotometer were used in the determinations of sodium and potassium, calcium and magnesium, and available iron respectively. The results indicated that levels of potassium were in medium range (moderately high);sodium levels were generally low when compared to Brook’s classification table. Levels of calcium were generally low and those of magnesium were moderate based on Brook’s table of classification. Levels of available iron which fall within the range of Quijano-Guerta (2003) were high;this implies such levels can lead to toxicity. In all locations, there was decrease in the levels of each metal in the samples with (5 - 10 cm) depth.

关键词： Deposition Environment Particulate Sediment Toxicity