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In-situ nonvolatile and volatile modulation for optical neural networks

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Advanced Photonics 2023年第5期5卷 1-2页

作者： Carlos A.Ríos Ocampo University of Maryland Department of Materials Science&EngineeringCollege ParkMarylandUnited States University of Maryland Institute for Research in Electronics and Applied PhysicsCollege ParkMarylandUnited States

High-performance integrated optical memristors are crucial in developing optical neural networks based on in-memory *** devices are building blocks capable of modulating the transmission of a propagating mode in a multilevel and nonvolatile fashion,thus allowing storage and multiplication of analog signals in the same device.1 Chalcogenide phase change materials(PCMs)are candidates for high-performance devices.

关键词： optical networks neural

Non-symmetric differentially subordinate martingales and sharp weak-type bounds for Fourier multipliers

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Science China Mathematics 2024年第8期67卷 1807-1826页

作者： Meryem Akboudj Yong Jiao Adam osękowski School of Mathematics and Statistics Hunan Key Laboratory of Analytical Mathematics and ApplicationsCentral South UniversityChangsha 410075China Faculty of Mathematics Informatics and MechanicsUniversity of WarsawWarsaw 02-097Poland

Let p>2 be a given *** this paper,we prove,with the best constant,the weak-type(p,p)inequality■for a large class of non-symmetric Fourier multipliers T_(m) obtained via modulation of jumps of certain Lévy *** particular,the estimate holds for appropriate linear combinations of second-order Riesz transforms and skew versions of the Beurling-Ahlfors operator on the complex *** proof rests on a novel probabilistic bound for Hilbert-space-valued martingales satisfying a certain non-symmetric subordination *** applications to harmonic functions and Riesz systems on Euclidean domains are indicated.

关键词： weak-type bound Fourier multiplier martingale differential subordination laminate

Antimicrobial, cytotoxicity, anticancer and antioxidant activities of Jatropha zeyheri ***(Euphorbiaceae)

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Asian Pacific Journal of Tropical Biomedicine 2019年第7期9卷 307-314页

作者： NI Mongalo os Soyingbe TJ Makhafola University of South Africa College of Agriculture and Environmental Sciences LaboratoriesPrivate Bag X06Florida0610South Africa Research Innovation&Engagements PortfolioMangosuthu University of TechnologyP O Box 12363Durban4026South Africa

Objective: To evaluate the antimicrobial, antioxidant, cytotoxicity and anticancer activity of fractions from Jatropha zeyheri roots and to explore the phytochemical profile of the most biologically active ***: Fractions from Jatropha zeyheri ethyl acetate extract were investigated for antimicrobial activity against a plethora of pathogenic microorganisms of different origins. The cytotoxicity studies of fractions were evaluated in vitro using tetrazolium-based calorimetric assay against human dermal fibroblast, colon adenocarcinoma(Caco-2), breast cancer(MCF-7) and lung cancer(A547) cell lines. The anti-oxidant activity of fractions was determined in vitro against 2,2-diphenyl-1-picrylhydrazyl(DPPH), 2,2′-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt(ABTS) and chelation of iron(Fe2+). Gas chromatography mass spectrometry analysis was performed to detect phytochemical constituents in fraction with potent biological ***: Fraction 2 of Jatropha zeyheri roots exhibited the lowest minimum inhibitory concentration of 40 μg/mL against Klebsiella pneumoniae and 80 μg/mL against Candida albicans, Staphylococcus aureus and Mycoplasma hominis. The fractions revealed some varying degrees of cytotoxicity against human dermal fibroblasts yielding LC50 values ranging from 28.96 to 166.52 μg/mL. Fraction 3 exhibited the highest selectivity index value of 2.08 against Klebsiella pneumoniae. Moreover, fraction 2 selectively inhibited the growth of Caco-2 with LC50 of 8.83 μg/mL, compared to other cancerous cell lines. Fraction 2 of Jatropha zeyheri further exhibited IC50 of 19.66, 22.63 and 1.82 μg/mL against DPPH, ABTS and Fe2+, respectively. Gas chromatography mass spectrometry analysis revealed the presence of cyclotetracosane(10.08%), 9-hexacosene(9.40%), hexadecanoic acid(3.90%),(Z)-9-octadecenamide(3.63%), octacosane(2.27%), 11-n-decylheneicosane(2.23%), ethyl vallesiachotamate(2.17%), heneicosanoic acid(2.10%), and octadecanoic a

关键词： Antimicrobial activity Selectivity index Jatropha zeyheri GC-MS Antioxidant activity Anti-proliferative effect

Hepatocellular carcinoma and food contamination: Ochratoxin A as a great prompter

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World Journal of Gastroenterology 2013年第24期19卷 3723-3725页

作者： Raphael JF Felizardo Niels os Cmara Division of Nephrology Department of Medicine Federal University of Sao PauloSao Paulo CEP 05508-900 Brazil Department of Immunology Institute of Biomedical Sciences University of S o PauloSao Paulo CEP 05508-900 Brazil

Ochratoxin A (OTA) is a secondary metabolite of Asper-gillus and Penicillium, microorganisms that can be haz-ardous to health when present as food contaminants. OTA is a potent member of a group of mycotoxins. Prolonged exposure to mycotoxins in the diet is related to cancer, among other diseases. Hepatocellular car-cinoma (HCC) accounts for 70%-90% of primary liver cancers and is the third leading cause of cancer-related deaths worldwide. In a recent study, Ibrahim et al proposed a correlation between the incidence of HCC and contamination with OTA. Analysis of OTA in serum samples showed that HCC patients had the highest incidence of OTA of the subjects examined (5-fold higher than that of the control group). OTA levels were significantly increased in HCC patients. This study demonstrates that chronic exposure to high levels of OTA may be associated with a high risk of liver cancer development. Future epidemiologic studies of HCC should focus on good practices in food preparation, food storage and the consumption of OTA-containing foods.

关键词： Ochratoxin A Mycotoxin Food contamination Hepatocellular carcinoma Liver cancer Egypt

Current advances in using tolerogenic dendritic cells as a therapeutic alternative in the treatment of type 1 diabetes

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World Journal of Diabetes 2021年第5期12卷 603-615页

作者： William de Jesús Ríos-Ríos Sorely Adelina Sosa-Luis Honorio Torres-Aguilar Department of Biochemical Sciences Faculty Universidad Autónoma“Benito Juárez”de OaxacaOaxaca 68120Mexico Department of Molecular Biomedicine Centro de Investigación y de Estudios Avanzados del Instituto Politécnico NacionalMexico City 07360Mexico

Type 1 diabetes(T1D)is an autoimmune disease characterized by the destruction of insulin-producingβ-cells of the pancreatic islets by autoreactive T cells,leading to high blood glucose levels and severe long-term *** typical treatment indicated in T1D is exogenous insulin administration,which controls glucose levels;however,it does not stop the autoimmune *** strategies have been implemented aimed at stoppingβ-cell destruction,such as cellular *** cells(DCs)as an alternative in cellular therapy have gained great interest for autoimmune disease therapy due to their plasticity to acquire immunoregulatory properties both in vivo and in vitro,performing functions such as anti-inflammatory cytokine secretion and suppression of autoreactive lymphocytes,which are dependent of their tolerogenic phenotype,displayed by features such as semimature phenotype,low surface expression of stimulatory molecules to prime T cells,as well as the elevated expression of inhibitory *** may be obtained and propagated easily in optimal amounts from peripheral blood or bone marrow precursors,such as monocytes or hematopoietic stem cells,respectively;therefore,various protocols have been established for tolerogenic(tol)DCs manufacturing for therapeutic research in the treatment of *** this review,we address the current advances in the use of tolDCs for T1D therapy,encompassing protocols for their manufacturing,the data obtained from preclinical studies carried out,and the status of clinical research evaluating the safety,feasibility,and effectiveness of tolDCs.

关键词： Type 1 diabetes Dendritic cells Autoimmunity Immune tolerance Cell therapy Immunotherapy.

Knowledge of aflatoxin contamination in groundnut and the risk of its ingestion among health workers in Ibadan,Nigeria

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Asian Pacific Journal of Tropical Biomedicine 2011年第6期1卷 493-495页

作者： Ilesanmi FF Ilesanmi os Nigerian Stored Products Research Institute Department of Community Medicine University College Hospital

Objective:To assess the awareness and knowledge of aflatoxin contamination in groundnut and the risk of its ingestion among health workers in ***:The study was a descriptive cross-sectional *** instrument was a semi-structured self administered questionnaire. The respondents were health workers from a public health ***:A total of 417 health workers participated out of which males were 60.2%.The mean age of respondents was(28.0±4.9) years *** made up 83.0%while others were nurses.95%of the respondents had previous awareness of aflatoxin and class room lectures was the most common source of information(56%).Occupation and religion both showed a significant association with previous awareness of aflatoxin(Possibility of incorporating aflatoxin awareness into routine health talk to increase the level of awareness of patients and their relatives.

关键词： Mycotoxins Groundnut Contamination Health risks Ingestion Neoplasm Aflatoxin

Floral biology and pollination mechanisms of four Mexico-endemic Fuchsia species with contrasting reproductive systems

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Journal of Plant Ecology 2018年第1期11卷 123-135页

作者： Clementina González Anai Alvarez-Baños Eduardo Cuevas CONACYT-Instituto de Investigaciones sobre los Recursos Naturales Universidad Michoacana de San Nicolás de HidalgoAv.San Juanito Itzícuaro s/nCol.Nueva EsperanzaMorelia Michoacán 58330México Facultad de Biología Universidad Michoacana de San Nicolás de HidalgoAv.Francisco J.Mújica S/NCiudad UniversitariaMoreliaMichoacán 58030México Departamento de Biología Vegetal y Ecología Universidad de SevillaApartado 109541080 SevillaSpain

Aims The evolution of the outstanding variation of reproductive systems in angiosperms has been considered an important driver of line-age *** related hermaphroditic and dioecious species with biotic pollination provide the opportunity to study and compare traits related to pollinator attraction and their con-sequences on reproductive components.A higher predictability of pollination syndromes is expected in dioecious species,which are dependent on pollinators,than in self-compatible hermaphroditic *** species may suffer pollen limitation depending on the quality of floral rewards and the kind and abundance of pollina-tors,whereas no pollen limitation is expected in hermaphroditic spe-cies with autonomous ***,in the absence of pollen limitation,more or better seeds are expected in dioecious species,according to the sexual specialization *** In natural populations of the hermaphroditic Fuchsia fulgens and Fuchsia arborescens and dioecious Fuchsia parviflora and Fuchsia obconica,all endemic to Mexico,we first described flower phenol-ogy,flower production and longevity and nectar volume and ***,we evaluated the correspondence between floral visitors and pollination *** hermaphrodite plants,we determined the level of herkogamy and the potential for autonomous ***,we evaluated the effect of pollen limitation on fruit set and seed number and assessed seed germination for all *** Findings In contrast to our prediction,dioecious species did not show a higher correspondence between pollination syndromes and floral visitors than did hermaphrodites;however,male flowers exhib-ited a higher correspondence than female *** pollen limitation was detected in dioecious species,for which visitation rate did not differ between male and female *** her-maphroditic *** showed pollen limitation for seed number,despite the presence of auto

关键词： dioecy herkogamy hermaphroditism pollen limitation pollination syndromes

High-risk symptoms and quantitative faecal immunochemical test accuracy: Systematic review and meta-analysis

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World Journal of Gastroenterology 2019年第19期25卷 2383-2401页

作者： Noel Pin Vieito Sara Zarraqui?os Joaquín Cubiella Department of Gastroenterology Complexo Hospitalario Universitario de Ourense Instituto de Investigación Sanitaria Galicia Sur Department of Biochemistry Genetics and Immunology Faculty of Biology University of Vigo

BACKGROUND The quantitative faecal immunochemical test for haemoglobin(FIT) has been revealed to be highly accurate for colorectal cancer(CRC) detection not only in a screening setting, but also in the assessment of patients presenting lower bowel symptoms. Therefore, the National Institute for Health and Care Excellence has recommended the adoption of FIT in primary care to guide referral for suspected CRC in low-risk symptomatic patients using a 10 μg Hb/g faeces ***, it is unknown whether FIT′s accuracy remains stable throughout the broad spectrum of possible *** To perform a systematic review and meta-analysis to assess FIT accuracy for CRC detection in different clinical *** A systematic literature search was performed using MEDLINE and EMBASE databases from inception to May 2018 to conduct a meta-analysis of prospective studies including symptomatic patients that evaluated the diagnostic accuracy of quantitative FIT for CRC detection. Studies were classified on the basis of brand,threshold of faecal haemoglobin concentration for a positive test result,percentage of reported symptoms(solely symptomatic, mixed cohorts) and CRC prevalence(< 2.5%, ≥ 2.5%) to limit heterogeneity and perform subgroup analysis to assess the influence of clinical spectrum on FIT′s accuracy to detect *** Fifteen cohorts including 13073 patients(CRC prevalence 0.4% to 16.8%) were identified. Pooled estimates of sensitivity for studies using OC-Sensor at 10 μg Hb/g faeces threshold(n = 10400) was 89.6% [95% confidence interval(CI): 82.7%to 94.0%). However, pooled estimates of sensitivity for studies formed solely by symptomatic patients(n = 4035) and mixed cohorts(n = 6365) were 94.1%(95%CI: 90.0% to 96.6%) and 85.5%(95%CI: 76.5% to 91.4%) respectively(P <0.01), while there were no statistically significant differences between pooled sensitivity of studies with CRC prevalence < 2.5%(84.9%, 95%CI: 73.4% to 92.0%)and ≥ 2.5%(91.7%, 95%CI: 83.

关键词： Bowel disease Colorectal cancer Diagnostic accuracy Faecal haemoglobin Faecal immunochemical test Faecal occult blood test Inflammatory bowel disease Significant colonic lesion

Vector-valued operators, optimal weighted estimates and the C_p condition

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Science China Mathematics 2020年第7期63卷 1339-1368页

作者： María Eugenia Cejas Kangwei Li Carlos Pérez Israel Pablo Rivera-Ríos BCAM—Basque Center for Applied Mathematics Bilbao 48009Spain CONICET Departamento de MatematicaFacultad de Ciencias ExactasUniversidad Nacional de La PlataLa Plata 1900Argentina Department of Mathematics University of the Basque CountryBilbao 48080Spain Ikerbasque Basque Foundation of ScienceBilbao 48013Spain INMABB CONICETDepartamento de MatematicaUniversidad Nacional del SurBahia Blanca 8000Argentina

In this paper some new results concerning the C_p classes introduced by Muckenhoupt(1981)and later extended by Sawyer(1983),are *** particular,we extend the result to the full expected range p>0,to the weak norm,to other operators and to their vector-valued *** of those results rely upon sparse domination,which in the vector-valued case are provided as *** will also provide sharp weighted estimates for vector-valued extensions relying on those sparse domination results.

关键词： A_p weights quantitative estimates C_p estimates vector-valued extensions sparse domination maximal functions Calderon-Zygmund operators commutators