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Intelligent Machine Learning Based Brain Tumor Segmentation through Multi-Layer Hybrid U-Net with CNN Feature Integration

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Computers, Materials & Continua 2024年第4期79卷 1301-1317页

作者： Sharaf j.Malebary Department of Information Technology Faculty of Computing and Information TechnologyKing Abdulaziz UniversityP.O.Box 344Rabigh21911Saudia Arabia

Brain tumors are a pressing public health concern, characterized by their high mortality and morbidity ***, the manual segmentation of brain tumors remains a laborious and error-prone task, necessitatingthe development of more precise and efficient methodologies. To address this formidable challenge, we proposean advanced approach for segmenting brain tumorMagnetic resonance Imaging (MrI) images that harnesses theformidable capabilities of deep learning and convolutional neural networks (CNNs). While CNN-based methodshave displayed promise in the realm of brain tumor segmentation, the intricate nature of these tumors, markedby irregular shapes, varying sizes, uneven distribution, and limited available data, poses substantial obstacles toachieving accurate semantic segmentation. In our study, we introduce a pioneering Hybrid U-Net framework thatseamlessly integrates the U-Net and CNN architectures to surmount these challenges. Our proposed approachencompasses preprocessing steps that enhance image visualization, a customized layered U-Net model tailoredfor precise segmentation, and the inclusion of dropout layers to mitigate overfitting during the training ***, we leverage the CNN mechanism to exploit contextual information within brain tumorMrI images,resulting in a substantial enhancement in segmentation *** experimental results attest to the exceptionalperformance of our framework, with accuracy rates surpassing 97% across diverse datasets, showcasing therobustness and effectiveness of our approach. Furthermore, we conduct a comprehensive assessment of ourmethod’s capabilities by evaluating various performance measures, including the sensitivity, jaccard-index, andspecificity. Our proposed model achieved 99% accuracy. The implications of our findings are profound. Theproposed Hybrid U-Net model emerges as a highly promising diagnostic tool, poised to revolutionize brain tumorimage segmentation for radiologists and clinician

关键词： Brain tumor Hybrid U-Net CLAHE transfer learning MrI images

The secondary injury cascade after spinal cord injury: an analysis of local cytokine/chemokine regulation

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Neural regeneration research 2024年第6期19卷 1308-1317页

作者： Daniel j.Hellenbrand Charles M.Quinn Zachariah j.Piper ryan T.Elder raveena r.Mishra Taylor L.Marti Phoebe M.Omuro rylie M.roddick jae Sung Lee William L.Murphy Amgad S.Hanna Department of Neurosurgery University of Wisconsin-Madison School of Medicine and Public Health Department of Biomedical Engineering University of Wisconsin-Madison Department of Orthopedics and rehabilitation University of Wisconsin-Madison Department of Materials Science and Engineering University of Wisconsin-Madison Forward BIO Institute University of Wisconsin-Madison

After spinal cord injury, there is an extensive infiltration of immune cells, which exacerbates the injury and leads to further neural degeneration. Therefore, a major aim of current research involves targeting the immune response as a treatment for spinal cord injury. Although much research has been performed analyzing the complex inflammatory process following spinal cord injury, there remain major discrepancies within previous literature regarding the timeline of local cytokine regulation. The objectives of this study were to establish an overview of the timeline of cytokine regulation for 2 weeks after spinal cord injury, identify sexual dimorphisms in terms of cytokine levels, and determine local cytokines that significantly change based on the severity of spinal cord injury. rats were inflicted with either a mild contusion, moderate contusion, severe contusion, or complete transection, 7 mm of spinal cord centered on the injury was harvested at varying times post-injury, and tissue homogenates were analyzed with a Cytokine/Chemokine 27-Plex assay. results demonstrated pro-inflammatory cytokines including tumor necrosis factor α, interleukin-1β, and interleukin-6 were all upregulated after spinal cord injury, but returned to uninjured levels within approximately 24 hours post-injury, while chemokines including monocyte chemoattractant protein-1 remained upregulated for days post-injury. In contrast, several anti-inflammatory cytokines and growth factors including interleukin-10 and vascular endothelial growth factor were downregulated by 7 days post-injury. After spinal cord injury, tissue inhibitor of metalloproteinase-1, which specifically affects astrocytes involved in glial scar development, increased more than all other cytokines tested, reaching 26.9-fold higher than uninjured rats. After a mild injury, 11 cytokines demonstrated sexual dimorphisms; however, after a severe contusion only leptin levels were different between female and male rats. In conclus

关键词： astrocytes chemokines cytokines inflammation macrophages microglia secondary damage spinal cord injury

Prevalence and Factors Associated with Positivity of Antinuclear Antibodies (ANA) Patterns, Native Anti-DNA and Extractable Nuclear Antigens (ENA) Antibodies: Experience from a Laboratory in Dakar

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Open journal of rheumatology and Autoimmune Diseases 2024年第1期14卷 26-36页

作者： Diop Abdou Diallo Thierno Abdoulaye Ndiaye Babacar Mahou Chantal Diop Marième Gaye Dubrous Phillippe Seck Abdoulaye medical Biology Laboratory Pasteur Institute of Dakar Dakar Senegal Cheikh Anta Diop University of Dakar Dakar Senegal

Background: Diagnosis of autoimmune diseases (AID) is challenging, due to overlapping features with other non-immune disorders. Anti-nuclear antibodies (ANA) are sensitive screening tests but anti-deoxyribonucleic acid-antibody (anti-DNA), and anti-extractable nuclear antigens (anti-ENA) are specific for AIDs. We aimed to look at ANA patterns in our patients and correlated them with anti-ENA for proper interpretation and better patient management cost-effectively. methods: A retrospective study was conducted over 1 year from january to December 2022 who were tested for ANA at biology medical laboratory of Pasteur Institute of Dakar. Anti-ENA and anti-DNA results were also analyzed for ANA-positive patients. Statistical analysis was performed using STATA 14.0, p results: 216 patients were analyzed. Women predominated at 79.2% and mean age was 48 years [CI 95%, 46 - 50], with extremes of 10 and 89. Most represented age group was [41 - 60] with 38%. ANA was positive in 27 (12.5%) of patients, 59.2% of whom were strongly positive (titer of 1/1000, 1/3200 or 1/6400). The most common pattern was nuclear speckled, which was found in 77.8% of samples. Anti-ENA and anti-DNA positivity in ANA-positive patients was found respectively in 63% (17/27) and 1.4% (3/27) of the samples analyzed. Most commonly identified anti-ENA was anti-Sm 29.6%, anti-SSA 29.6%, anti-ro-52 25.9%, anti-rNP 18.5% and anti-SSB 14.8% which was associated with speckled pattern. Association results indicated a significant relationship between both tests and between ANA titer in the anti-ENA- and ANA-positive patients (p 0.001). Conclusions: ANA, Anti-ENA and anti-DNA antibodies are essential for AIDS diagnosis. However, the testing repertoire should follow an algorithm comprising of clinical features, followed by ANA results with nuclear, mitotic, and cytoplasmic patterns, anti-ENA, and anti-DNA for a more meaningful, and cost-effective diagnostic approach.

关键词： Antinuclear Antibodies Extractable Nuclear antigen Autoimmune Disease Indirect Immunofluorescence

Laboratory evaluation of toxicity of selected insecticides against egg and larval stages of cotton pink bollworm, Pectinophora gossypiella (Saunders) (Lepidoptera: Gelechiidae)

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journal of Cotton research 2024年第1期7卷 15-28页

作者： BUSNOOr Abhishek V. WADASKAr r.M. FAND Babasaheb B. TAMBE V.j. PILLAI T. MAHULE D.j. NAGrArE V.S. PrASAD Y.G. Entomology Section College of Agriculture(Dr.Panjabrao Deshmukh Krishi Vidyapeeth)Nagpur 440001MaharashtraIndia Indian Council of Agricultural research-Central Institute for Cotton research Nagpur 441108MaharashtraIndia

Background The cryptic nature of pink bollworm Pectinophora gossypiella(Saunders)larvae enables its reduced vul-nerability to insecticidal ***,the development of resistance against Bacillus thuringiensis(Bt)toxins posed a serious threat to transgenic cotton *** necessitated determining the critical timing of spray applications on the control *** study assessed the influence of egg age(freshly laid ***-day-old)and the loca-tion of larvae(directly exposed to the insecticide residues on the boll rind *** inside the bolls)on insecticide control *** The results revealed a significant decrease in the ovicidal activity of tested insecticides with an increase in the age of eggs from one day old to three days old(paired t-test,Prvae directly exposed to the insec-ticide residues on the boll rind were more susceptible(>80%mortality)than the larvae exposed after they had bur-rowed inside the bolls(rtality).The inhibitory effects of tested insecticides on developmental biology were more pronounced in the experiment on pre-larval release insecticide treatment compared with insecticide treatment given post-larval release and entry inside the *** Egg age influences the insecticide susceptibility,as does the larval location,directly exposed vs bur-rowed inside the *** eggs and the larvae that had burrowed inside the green bolls of cotton were relatively less susceptible to the insecticide *** toxic effects of insecticides on egg and larval stages were primar-ily *** findings are significant for devising a comprehensive strategy for pink bollworm management on a sustainable basis.

关键词： Bioefficacy Cotton Insecticides Pink bollworm Pectinophora gossypiella Timings of spray

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rodent biology and ecologically based rodent management(EBrM)-25 years of progress through promoting multidisciplinary research

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Integrative Zoology 2024年第1期19卷 2-7页

作者： Grant r. SINGLETON Lyn A. HINDS rhodes MAKUNDI Steven r. BELMAIN Natural resources Institute University of Greenwich Kent UK CSIrO Health and Biosecurity Canberra ACT Australia African Centre of Excellence for Innovative rodent Pest Management and Biosensor Technology Development Sokoine University of Agriculture Morogoro Tanzania Institute of Pest Management Sokoine University of Agriculture Morogoro Tanzania

“During rodent outbreak years in eastern Africa,lo-cally,more than 80%of the potential harvest may be lost,but even in non-outbreak periods,rodents cause chronic damage to crops….The pest rodent story in Africa in-volves several species embedded in a broad and variable landscape with highly variable densities.”(Leirs et al.2010).

关键词： damage crops

Compressive property and energy absorption characteristic of interconnected porous Mg-Zn-Y alloys with adjusting Y addition

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journal of Magnesium and Alloys 2024年第1期12卷 171-185页

作者： j.A.Liu S.j.Liu B.Wang W.B.Sun X.j.Liu Z.W.Han College of Materials Science and Engineering Key Laboratory of Automobile Materials(Ministry of Education)Jilin UniversityChangchun 130022PR China Key Laboratory of Bionic Engineering(Ministry of Education) College of Biological and Agricultural EngineeringJilin UniversityChangchun130022PR China Weihai Institute for Bionics-jilin University Weihai 264205PR China

In this study,interconnected porous Mg-2Zn-xY alloys with different phase compositions were prepared by various Y additions(x=0.4,3,and 6 wt.%)to adjust the compressive properties and energy absorption *** characterization methods were then applied to identify the microstructure of the porous Mg-Zn-Y and describe the details of the second *** tests were performed at room temperature(rT),200℃,and 300℃to study the impact of the Y addition and testing temperature on the compressive properties of the porous *** experimental results showed that a high Y content promotes a microstructure refinement and increases the volume fraction of the second *** the Y content increases,different Mg-Zn-Y ternary phases appear:I-phase(Mg_(3)Zn_(6)Y),W-phase(Mg_(3)Zn_(3)Y_(2)),and LPSO phase(Mg_(12)ZnY).When the Y content ranges between 0.4%and 6%,the compressive strength increases from 6.30MPa to 9.23 MPa,and the energy absorption capacity increases from 7.33 Mj/m^(3)to 10.97 Mj/m^(3)at rT,which is mainly attributed to the phase composition and volume fraction of the second ***,the average energy absorption efficiency is independent of the Y *** addition,the compressive deformation behaviors of the porous Mg-Zn-Y are altered by the testing *** compressive strength and energy absorption capacity of the porous Mg-Zn-Y decrease due to the softening effect of the high temperature on the *** deformation behaviors at different temperatures are finally observed to reflect the failure mechanisms of the struts.

关键词： Porous magnesium rare earth elements Microstructure Compressive behavior Energy absorption characteristic

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The quasi-Gramian solution of a non-commutative extension of the higher-order nonlinear Schr?dinger equation

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Communications in Theoretical Physics 2024年第3期76卷 51-61页

作者： H W A riaz j Lin Department of Physics Zhejiang Normal UniversityJinhua 321004China

The nonlinear Schr?dinger(NLS)equation,which incorporates higher-order dispersive terms,is widely employed in the theoretical analysis of various physical *** this study,we explore the non-commutative extension of the higher-order NLS *** treat real or complex-valued functions,such as g_(1)=g_(1)(x,t)and g_(2)=g_(2)(x,t)as non-commutative,and employ the Lax pair associated with the evolution equation,as in the commutation *** derive the quasi-Gramian solution of the system by employing a binary Darboux *** soliton solutions are presented explicitly within the framework of *** visually understand the dynamics and solutions in the given example,we also provide simulations illustrating the associated ***,the solution can be used to study the stability of plane waves and to understand the generation of periodic patterns within the context of modulational instability.

关键词： integrable systems Darboux transformation solitons

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Low-Cost and Biodegradable Thermoelectric Devices Based on van der Waals Semiconductors on Paper Substrates

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Energy & Environmental Materials 2024年第1期7卷 205-210页

作者： Gulsum Ersu Carmen Munuera Federico j.Mompean Daniel Vaquero jorge Quereda jo?o Elias F.S.rodrigues jose A.Alonso Eduardo Flores jose r.Ares Isabel j.Ferrer Abdullah M.Al-Enizi Ayman Nafady Sruthi Kuriakose joshua O.Island Andres Castellanos-Gomez Materials Science Factory Instituto de Ciencia de Materiales de Madrid (ICMM-CSIC) Nanotechnology Group USAL–Nanolab Univesidad de Salamanca GISC Departamento de Física de Materiales Universidad Complutense de Madrid Departamento de Física Aplicada Centro de Investigación y Estudios Avanzados MIrE Group Departamento de Física de Materiales Universidad Autónoma de Madrid Instituto Nicolás Cabrera Universidad Autónoma de Madrid Department of Chemistry College of Science King Saud University Department of Physics and Astronomy University of Nevada Las Vegas

We present a method to fabricate handcrafted thermoelectric devices on standard office paper *** devices are based on thin films of WS2,Te,and BP（P-type semiconductors） and TiS3and TiS2（N-type semiconductors）,depo... 详细信息

关键词： paper-based electronics Seebeck effect semiconductors thermoelectrics van der Waals materials

Basis for the diversity and extent in loss of digestible nutrients created by dietary phytin: Emphasis on fowl and swine

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Animal Nutrition 2024年第1期16卷 422-428页

作者： Edwin T.Moran Michael r.Bedford Poultry Science Department Auburn University AB Vista Woodstock Court Blenheim Road

Phytin is the Ca2+-Mg2+-K+salt of phytic acid that is created and deposited in the aleurone layer and/or germ of grains and legumes. Its high presence in feedstuffs for fowl and swine diets results in it being a universal and significant impediment to optimum performance. Phytin impairs gastrointestinal recovery of a wide array of nutrients, the effect varying with the nutrient concerned. On exposure to low pH during gastric digestion, phytin dissociates into phytic acid and solubilized Ca2+. Even at low gastric pH,phytic acid is negatively charged which forms the basis of its anti-nutritive behavior. Pepsinogen has extensive basic amino acids on its activation peptide that are presented as cations at low pH which are targeted by pepsin for activation. Partially crystalized Ca2+near the enzyme?s active site further stabilizes its newly formed structure. Thus, phytic acid appears to interfere with gastric digestion by several mechanisms; interfering with pepsinogen activation by binding to the polypeptide?s basic amino acids;coordinating free Ca2+, destabilizing pepsin; binding some dietary proteins directly, further compromising gastric proteolysis. Upon digesta attaining neutrality in the duodenum, Ca2+and other cations rebind with accessible an.on., phytic acid being a significant contender. Phytate not only binds free cations but can also strip them from enzymes(e.g. Ca2+, Zn2+) which reduces their structural resistance to autolysis and ability as co-factors(e.g. Zn2+) to increase enzyme activity. Goblet cells initially employ Ca2+as an electronic shield between mucin layers enabling granule formation and cell storage. After mucin granule release, Ca2+is progressively displaced by Na+to free the viscous mucins enabling its translocation. Mucin entangles with the glycocalyx of adjacent enterocytes thereby constructing the unstirred water layer（USWL）. Excessive removal of Ca2+from mucin by phytic acid increases its fluidity facilitating its loss from the USWL with

关键词： Digestive enzyme Calcium Endogenous protein Mucin Phytin