检索结果-南通市图书馆

Bioprospecting optimal phenology for bioactive molecules in native golden yellow Pleurotus citrinopileatus Singer

Asian Pacific Journal of Tropical Biomedicine 2016年第2期6卷 132-142页

作者： Godfrey Nattoh Erastus Gatebe fredrick musieba Julius Mathara Department of Molecular Biology and Biotechnology Pan African University Institute for Basic SciencesTechnology and Innovation Research Technology and Innovation Department Kenya Industrial Research and Development Institute Department of Chemistry Jomo Kenyatta University of Agriculture Science and Technology Department of Food Science and Technology Jomo Kenyatta University of Agriculture Science and Technology

Objective: To bioprospect optimal phenological phases as source of novel molecules from native golden yellow Pleurotus citrinopileatus across four phenologies in both aqueous and ethanol extracts, and identify novel molecules responsible for these ***: Standard qualitative assay, Folin–Ciocalteu assay; aluminium chloride spectrophotometric, 2, 2-diphenyl-1-picrylhydrazyl, 2, 20-azinobis(3-ethylbenzothiazoline-6-suslfonic acid, ferricyanide reducing antioxidant power were used to determine total flavonoid, polyphenols, radical scavenging, and reducing power. Spectrophotometric methods were used for lycopene, b-carotene, and total carotenoids, while liquid chromatography quadrupole time of flight mass spectrometry was used for identification and comparative quantitation of polyphenols and flavonoids across the four phenological states. Chem Spider? database was used for the identification of compounds based on their empirical formula, accurate mass and literature review of previously reported compounds in ***: Primordial phases exhibited higher contents of secondary metabolites than mature basidiocarps. Polyphenols content differed across physiological phases with primordials exhibiting significant high contents(P < 0.05) [(13.803 ± 0.797) mg gallic acid equivalent/g dry weight]. Distribution of total flavonoids was significantly different(P < 0.05) across physiological states and ranged from(3.311 ± 0.730) to(14.824 ± 0.890) mg quercetin equivalent g dry weight. Ten polyphenol acids and seven flavonoids compounds identified varied across these phases with primordials exhibiting relatively high peak areas. Total antioxidant activities showed a positive correlation with total polyphenols(r = 0.969;P < 0.05) and total flavonoids(r = 0.960; P < 0.05) across these ***: These findings provide evidence that primordials of golden yellow mushroom as opposed to their fruiting bodies are potent sources of bioactive health molecule

关键词： Bioprospecting Primordial Phenology Bioactive molecules Liquid chromatography-quadrupole time of flight mass spectrometry Edible fungi

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

An Efficient Smoothing and Thresholding Image Segmentation Framework with Weighted Anisotropic-Isotropic Total Variation

引用

Communications on Applied Mathematics and Computation 2024年第2期6卷 1369-1405页

作者： Kevin Bui Yifei Lou fredrick Park Jack Xin Department of Mathematics University of CaliforniaIrvineIrvineCA 92697-3875USA Department of Mathematics University of North CarolinaChapel HillChapel HillNC 27599.USA Department of Mathematics and Computer Science Whittier CollegeWhittierCA 90602USA

In this paper,we design an efficient,multi-stage image segmentation framework that incorporates a weighted difference of anisotropic and isotropic total variation(AITV).The segmentation framework generally consists of two stages:smoothing and thresholding,thus referred to as smoothing-and-thresholding(SaT).In the first stage,a smoothed image is obtained by an AITV-regularized Mumford-Shah(MS)model,which can be solved efficiently by the alternating direction method of multipliers(ADMMs)with a closed-form solution of a proximal operator of the l_(1)-αl_(2) *** convergence of the ADMM algorithm is *** the second stage,we threshold the smoothed image by K-means clustering to obtain the final segmentation *** experiments demonstrate that the proposed segmentation framework is versatile for both grayscale and color images,effcient in producing high-quality segmentation results within a few seconds,and robust to input images that are corrupted with noise,blur,or *** compare the AITV method with its original convex TV and nonconvex TVP(O

关键词： Image segmentation Non-convex optimization Mumford-Shah(MS)model Alternating direction method of multipliers(ADMMs) Proximal operator

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

A Case Report on Cutaneous Larva Migrans (CLM)

引用

Case Reports in Clinical Medicine 2024年第9期13卷 353-357页

作者： fredrick Sinyinza Charles Lukanga Kimera Linda Ndesipandula Lukolo Department of Maternal & Child Health Paediatrics School of Medicine University of Namibia Windhoek Namibia Department of Obstetrics & Gynaecology Onandjokwe Intermediate Hospital Ministry of Health & Social Services Windhoek Namibia Department of Community and Family Medicine School of medicine University of Namibia Windhoek Namibia

Cutaneous larva migrans (CLM) is a zoonotic hookworm infection of dogs and cats commonly found in low-income countries in the tropical and subtropical regions and travellers to these regions. It is caused by invasion of the skin by the parasitic larvae of hookworms which, after entry, move under the skin causing an inflammatory reaction resulting in a single or multiple tracks. Patients commonly present with a progressive, itchy, erythematous serpiginous skin rash, affecting the feet, although it can affect any other parts of the body. The diagnosis is mainly clinical, based on history and physical examination. Treatment of this condition can effectively be achieved with either albendazole or ivermectin. We present a case of a 7-year-old boy who was diagnosed with CLM after presenting to the hospital with a history of a progressive itchy rash with tracks on the left foot. Although CLM is a self-limiting disease, it causes a lot of suffering and, therefore, it is of public concern. There is a need to increase awareness of this disease among health workers, and to implement and promote preventive measures against the disease since the cause is known.

关键词： Cutaneous Larva Larva Migrans Zoonosis Tropical Disease Pruritus Hookworm Creeping Eruption

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Intracranial pressure is elevated at 24h post-stroke inmice

引用

Neuroprotection 2024年第1期2卷 60-64页

作者： Kirby E.Warren Rebecca J.Hood fredrick R.Walker Neil J.Spratt School of Biomedical Sciences and Pharmacy University of NewcastleCallaghanAustralia Hunter Medical Research Institute NewLambton HeightsAustralia School of Biomedicine Discipline of Anatomy and PathologyFaculty of Health and Medical SciencesThe University of AdelaideAdelaideAustralia Department of Neurology John Hunter HospitalNewLambton HeightsAustralia

Background:It has long been assumed that post-stroke intracranial pressure(ICP)elevation occurs because of large infarct and edema ***,we have repeatedly shown IcP elevation at 24 h post-stroke in the presence of little to no edema in *** processes are often conserved across species and types of ***,we aimed to determine if an ICP rise occurs at 24 h post-stroke in the presence of small infarct and edema volumes in ***:Mice were randomized by random number table to either photothrombotic stroke or sham surgery(n=15).Epidural ICP was recorded using a fiber optic catheter at 1 h post-stroke(baseline)and between 23 and ***:ICP was significantly higher at 24 h compared to baseline in stroke animals(n=6;10.71±6.45mmHg vs.3.74±2.20mmHg,respec-tively;p=0.03).ICP at 24 h was also significantly higher in stroke mice compared to sham(n=6;3.45±1.43mmHg;p=0.02).There was no change in ICP in sham mice(p=0.9).Edema volumes in stroke animals were small(0.04±0.04 mm3)and unlikely to have caused significant ICP ***:This study provides evidence of an edema-independent ICP elevation following small ischemic stroke in *** occurrence of this rise supports our findings in other species and suggests it is caused by a previously undescribed mechanism.

关键词： cerebraledema intracranial pressure ischemic stroke

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Effects of Papyrus Plants (Cyperus papyrus) on the Physicochemical Parameters and Nutrient Levels of Water and Sediments in Yala Swamp Wetland in Western Kenya

引用

Journal of Biophysical Chemistry 2024年第1期15卷 1-23页

作者： Violet Achieng Orodo Paul Otieno Abuom Emmanuel Amukohe Shikanga Elly Tetty Osewe Douglas Nyambane Anyona fredrick Mhina Mngube Stephen Adongo Odongo Department of Environmental Studies Maseno University Kisumu Kenya Department of Chemistry Maseno University Kisumu Kenya Department of Physical and Biological Sciences Murang’a University of Technology Murang’a Kenya Wetlands International Dar es Salaam Tanzania Department of Physical Sciences Jaramogi Oginga Odinga University of Science and Technology Bondo Kenya

Yala swamp wetland is the largest fresh water wetland ecosystem in Kenya supporting a broad biodiversity. It comprises of River Yala, the Yala swamp, Lakes Kanyaboli, Namboyo and Sare, and a portion of Lake Victoria neighboring the swamp. Approximately 2300 ha of land have been reclaimed and has been used for large-scale agriculture resulting in mass destruction of papyrus to create room for framing. Papyrus are known to be important in phytoremediation but despite this role information is limited, lacks supportive evidence and the empirical aspect on the levels of these pollutants in relation to the papyrus biomass is limited. The study is aimed at determining the effects of Cyperus papyrus on the water and sediment quality in Yala Swamp wetland. Six sampling sites were purposefully selected to monitor the variations of the physicochemical parameters (temperature, dissolved oxygen: DO, pH, biological oxygen demand: BOD, total suspended solids: TSS, turbidity, electrical conductivity: EC and total dissolved solids: TSS) and the levels selected nutrients (phosphorus and nitrates) in water and sediments as River Yala flows through Dominion Farms, Lake Sare which surrounded by Cyperus papyrus and finally into Lake Victoria. The samples were collected in triplicates during the wet and dry seasons (May and September 2015 respectively). The physicochemical parameters were measured in situ using a Hydrolab muiltimeter while the nutrients were analyzed using UV/Vis spectroscopy. Statistical analysis was done using SAS V9.0 software. The mean temperature was 26.19˚C ± 0.71˚C, DO: 3.72 ± 1.02 Mg/l, BOD: 3.9 ± 0.32 Mg/l, pH: 7.52 ± 0.17, TDS: 109 ± 86.33, EC: 173.26 ± 13.8 μS/cm, TSS: 12.42 ± 18.51 Mg/l and Turbidity: 12.29 ± 10.03 NTU. The values varied significantly at P 0.05 among all the sites. The results show that papyrus is useful in maintaining the required levels of physicochemical parameters. The study will assist in conservation of the papyrus to help phytoremediate

关键词： Adsorbing Contaminants Phytoremediation Conservation Cyperus papyrus

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Kinetics and Morphological Analysis of Silver Platinum Bimetallic Nanoparticles

引用

Acta Metallurgica Sinica(English Letters) 2016年第4期29卷 320-325页

作者： fredrick Okumu Mangaka Matoetoe Department of Chemistry Cape Peninsula University of Technology

Kinetics of a one-pot core-shell synthesis of bimetallic （BM） silver-platinum （Ag-Pt） nanoparticles （NPs） by simultaneous reduction of 1：1 mol fraction of precursors H2PtC16.6H20 and AgNO3 in aqueous solution is reported. Kinetics analysis was done by plotting UV-visible absorptions versus reaction time with a first-order fitting. Recorded constants of Ag NPs （0.079 s^-1）, Ag-Pt NPs 1：1 （0.082 s^-1）, and Pt NPs （0.006 s^-1） were obtained. The NPs suspension solutions were clear, free from AgCl precipitate, and had characteristic optical properties of 450 nm （Ag NPs）, while there were no observable bands for Pt and BM NPs. Morphological analysis using transmission electron microscopy, energy- dispersive X-ray spectroscopy （EDX）, and selected area electron diffraction （SAED） depicted spherical aggregates of Ag NPs, Pt NPs and core shell Pt-Ag NPs 1：1 of average size of 60, 2.5, and 20 mm, respectively. Presence of the Ag and Pt elemental composition in the nanoparticle suspensions was confirmed by EDX. SAED ring patterns revealed a single facecentered cubic crystalline nature of Ag NPs and showed typical Pt-based BMs randomly overlapped ring pattern with sharp diffraction spots.

关键词： Platinum Silver Bimetallic nanoparticles Kinetics Morphology

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of Bimodal Grain Size Distribution on the Strain Hardening Behavior of a Medium-Entropy Alloy

引用

Acta Metallurgica Sinica(English Letters) 2021年第4期34卷 465-475页

作者： Ibrahim Ondicho Bernard Alunda fredrick Madaraka Melody Chepkoech Department of Mechanical Engineering Dedan Kimathi University of TechnologyPrivate bag-10143Dedan KimathiNyeriKenya Materials Designand Manufacturing(MADEMA)GroupDedan Kimathi University of TechnologyPrivate Bag-10143Dedan KimathiNyeriKenya Department of Mining and Minerals Processing Engineering Taita Taveta UniversityP.O.Box 635-80300VoiKenya Department of Mechanical Engineering Howard University23006th Street NWWashingtonDCUSA

The evolution of strain hardening behavior of the Fe_(50)(CoCrMnNi)_(50) medium-entropy alloy as a function of the fraction of recrystallized microstructure and the grain size was studied using the Hollomon and Ludwigson *** specimens under study were partially recrystallized,fully recrystallized with ultrafine-grained microstructure,and fully recrystallized with coarse *** yield strength decreases steadily as the fraction of recry stallized micro structure and grain size increases due to the recovery process and the Hall-Petch ***,the bimodal grain distribution was found to have a significant impact on strain hardening during plastic *** instance,the highest ultimate tensile strength was exhibited by a 0.97 μm specimen,which was observed to contain a bimodal grain ***,using the Ludwigson equation,the effect of the bimodal grain distribution was established from the behavior of K_(2) and n_(1) *** curves tend to show very high values in the specimens with a bimodal grain distribution compared to those that show a homogenous grain ***,the bimodal grain distribution contributes to the extensive Luders strain observed in the 0.97 μm specimen,which induces a significant deviation of the Hollomon equation at lower strains.

关键词： Metals and alloy Mechanical properties Microstructure High-entropy alloys Plastic deformation

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Circuit reorganization in cerebellar cultures after injury

引用

Neural Regeneration Research 2015年第7期10卷 1045-1046页

作者： fredrick J.Seil Department of Neurology Oregon Health & Science University

As elaborated in a recent review（Seil,2014）,we used an easily manipulable cerebellar culture system to study injury-induced reorganizational changes in a simplified central nervous system（CNS）*** structural and fu... 详细信息

关键词： Circuit reorganization in cerebellar cultures after injury cell

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

D-Dimer: Predictor of Postpartum Hemorrhage among Pre-Eclampsia at Kilimanjaro Christian Medical Centre

引用

Open Journal of Obstetrics and Gynecology 2024年第6期14卷 923-937页

作者： Husna Silim Ally Nyasatu G. Chamba Raziya Gaffur Nasra Batchu Glory Mangi Pendo S. Mlay Bariki Mchome Mtoro J. Mtoro Thomas J. Kakumbi Rafiki N. Mjema Doris Rwenyagila Eusebius Maro fredrick Mbise Gilleard Masenga Patricia S. Swai Department of Obstetrics and Gynaecology KCMC Hospital Moshi Tanzania Department of Obstetrics and Gynaecology Kilimanjaro Christian Medical University College (KCMUCo) Moshi Tanzania

Background: Postpartum hemorrhage (PPH) is the major contributor to maternal mortality and morbidity worldwide as well as in Tanzania. Studies have shown Pre-eclampsia as a risk indicator for Postpartum hemorrhage and D-dimer tends to rise in women with pre-eclampsia. Few studies that have shown the association between D-dimer and PPH have been controversial and differ according to ethnicity and lifestyle. Hence there is no suitable reference interval for D-dimer in predicting Postpartum hemorrhage among women with pre-eclampsia. Broad Objective: This study aimed to assess the association, sensitivity, and specificity of D-dimer as a laboratory predictor of postpartum hemorrhage among women with pre-eclampsia at KCMC hospital. Methodology: This was a hospital-based analytical cross-sectional study conducted at KCMC Hospital in Northern Tanzania from September 2022 to March 2023. A total of 195 women with pre-eclampsia were included in this study. Plasma D-dimer levels were taken from women with pre-eclampsia pre-delivery. Haematocrit was compared before and after delivery, and a fall of 10% was considered as Postpartum hemorrhage together with clinical assessment of the patient. Participants were divided among those who had severe features and those who did not have severe features and were further categorized into those who had PPH and those who did not have PPH. Logistic regression was used to determine the association between D-dimer and PPH adjusting for other factors. The Receiver Operating Curve (ROC) was used to evaluate the predictive value. Results: Higher median D-dimer levels were seen among women who had PPH compared to those who had no PPH. D-dimer was seen to be associated with PPH, thus for every unit increase of µg/ml of D-dimer among women who had pre-eclampsia without severe features there was a 14% significant increase in the odds of having postpartum hemorrhage and a 45% significant increase of having postpartum hemorrhage among those who had pre

关键词： D-Dimer Preeclampsia Postpartum Hemorrhage Tanzania

来源：

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

DoS detections based on association rules and frequent itemsets

引用

Journal of Harbin Institute of Technology(New Series) 2008年第2期15卷 283-289页

作者： George S Oreku fredrick JMtenzi 李建中 Dept.of Computer Science and Engineering Harbin Institute of Technology School of Computing Dublin Institute of Technology

To detect the DoS in networks by applying association rules mining techniques, we propose that association rules and frequent itemsets can be employed to find DoS pattern in packet streams which describe traffic and user behaviors. The method extracts information from the log analysis of submitted packets using the algorithm which depends on the definition of the intrusion. Large itemsets were extracted to represent the super facts to build the association analysis for the intrusion. Network data files were analysed for experiments. The analysis and experimental results are encouraging with better performance as packet frequency number increases.

关键词： data mining intrusion packets streams

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：