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Bioactive Materials 2020年第1期5卷 26-33页

作者： Afrah Al Hegy Ryan Smith eric R.Gauthier joy e.gray-munro Dept.of Chemistry and Biochemistry Laurentian UniversitySudburyOntarioP3E 2C6Canada

Magnesium and its alloys are promising candidates for a new generation of biodegradable metals in orthopaedic applications due to their excellent biocompatibility,biodegradability,and mechanical properties that are similar to natural bone.However,direct in vitro assessment of these materials in the presence of cells is complicated by degradation products from the alloy that lead to a false positive for the most commonly used cell adhesion and cell proliferation assays.In this paper,a cyanine dye was used to quantitatively evaluate the in vitro biocompatibility of a Mg AZ31 alloy by both direct and indirect methods.The cytotoxicity of the corrosion products was evaluated via an indirect method;a 25%decrease in cell viability compared to control samples was observed.Moreover,direct assessment of cell adhesion and proliferation showed a statistically significant increase in cell number at the surface after 72 h.In addition,the degradation rate and surface characteristics of the Mg AZ31 alloy were evaluated for both direct and indirect tests.The degradation rate was unaffected by the presence of cells while evidence of an increase in calcium phosphate deposition on the magnesium alloy surface in the presence of cells was observed.This study demonstrates that a cyanine dye based assay provides a more accurate assessment of the overall in vitro biocompatibility of biodegradable metals than the more commonly used assays reported in the literature to date.

关键词： Magnesium alloys Biocompatibility Direct method Indirect method Cyanine dye Cell adhesion Cell proliferation Cytotoxicity

Influence of mixed organosilane coatings with variable RGD surface densities on the adhesion and proliferation of human osteosarcoma Saos-2 cells to magnesium alloy AZ31

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Bioactive Materials 2017年第1期2卷 35-43页

作者： Xiaoxi Yang Afrah Al Hegy eric R.Gauthier joy gray-munro Dept.of Chemistry and Biochemistry Laurentian UniversitySudburyOntarioP3E 2C6Canada

In the last decade,the use of magnesium and its alloys as biodegradable implant materials has become increasingly accepted.However,surface modification of these materials to control the degradation rate in the early stages of healing and improve their biocompatibility is crucial to the successful implementation of magnesium alloy implants in medicine.Cell adhesion and proliferation at the implant surface is a vital factor for successful integration of a biomaterial within the body.Cells accomplish this task by binding to ligands such as the arginine-glycine-aspartic acid peptide sequence(RGD)commonly found on adhesive proteins present in the extracellular matrix.In this paper,we report a biomimetic surface modification strategy involving deposition of a mixed organosilane layer on Mg AZ31 followed by covalent immobilization of RGD peptides through a heterobifunctional cross-linker molecule.Our results indicate that with optimized deposition conditions uniform organosilane coatings were successfully deposited on the Mg AZ31 substrate.Furthermore,we have demonstrated that the surface density of immobilized RGD can be varied by depositing organosilane layers from solutions containing two different organosilanes in specified ratios.Increases in cell adhesion and cell proliferation were observed on the surface modified substrates.

关键词： Magnesium alloys Biodegradable Biomimetic RGD peptide Surface modification Cell adhesion Organosilane

Analysis of cellulolytic and hemicellulolytic enzyme activity within the Tipula abdominalis （Diptera： Tipulidae） larval gut and characterization of Crocebacterium ilecola gen. nov., sp. nov., isolated from the Tipula abdominalis larval hindgut

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Insect Science 2010年第3期17卷 291-302页

作者： Theresa e. Rogers joy Doran-Peterson Microbiology Department University of Georgia Athens Georgia USA

In forested stream ecosystems of the north and eastern United States, larvae of the aquatic crane fly Tipula abdominalis are important shredders of leaf litter detritus. T. abdominalis larvae harbor a dense and diverse microbial community in their hindgut that may aide in the degradation oflignocellulose. In this study, the activities ofcellulolytic and hemicellulolytic enzymes were demonstrated from hindgut extracts and from bacterial isolates using model sugar substrates. One of the bacterial isolates was further characterized as a member of the family Microbacteriaceae. Taxonomic position of the isolate within this family was determined by a polyphasic approach, as is commonly employed for the separation of genera within the family Microbacteriaceae. The bacterial isolate is Gramtype positive, motile, non-sporulating, and rod-shaped. The G ＋ C content of the DNA is 64.9 mol%. The cell wall contains B2y type peptidoglycan, D- and L-diaminobutyric acid as the diamino acid, and rhamnose as the predominant sugar. The predominant fatty acids are 12-methyltetradecanoic acid （ai-C15：0） and 14-methylhexadecanoic acid （ai-C17：0）. The isolate forms a distinct lineage within the family Microbacteriaceae, as determined by 16S rRNA sequence analysis. We propose the name Crocebacterium ilecola gen. nov., sp. nov., to accommodate this bacterial isolate. The type species is T202T （ATCC BAA-1359; GenBank Accession DQ826511）.

关键词： cellulolytic hemicellulolytic hindgut

Insights into the role of major bioactive dietary nutrients in lamb meat quality:a review

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Journal of Animal Science and Biotechnology 2022年第4期13卷 951-966页

作者： JavierÁlvarez-Rodríguez Olaia Urrutia Sandra Lobón Guillermo Ripoll Juan Ramón Bertolín Margalida joy Departament de Ciència Animal Universitat de Lleida25198 LleidaSpain Departamento de Agronomía Biotecnología y AlimentaciónIS-FOOD InstituteEscuela Técnica Superior de Ingeniería Agronómica y BiocienciasUniversidad Pública de NavarraPamplonaSpain Centro de Investigación y Tecnología Agroalimentaria de Aragón(CITA) Avda.Montañana 93050059 ZaragozaSpain Instituto Agroalimentario de Aragón–IA2(CITA-Universidad de Zaragoza) Avda.Miguel Servet17750013 ZaragozaSpain.

Feed supplementation withα-linolenic acid(ALA)and linoleic acid(LA)increases their content in muscle,ALA increases n-3 polyunsaturated fatty acids and decrease n-6/n-3 ratio in muscle,and LA increases rumenic acid.However,high LA supplementation may have negative effects on lambs’lipid oxidative stability of meat.When the sources of ALA and LA are fed as fresh forage,the negative effects are counterbalanced by the presence of other bioactive compounds,as vitamin e(mainlyα-tocopherol)and polyphenols,which delay the lipid oxidation in meat.There is a wide consensus on the capability of vitamin e delaying lipid oxidation on lamb meat,and its feed content should be adjusted to the length of supplementation.A high dietary inclusion of proanthocyanidins,phenolic compounds and terpenes reduce the lipid oxidation in muscle and may improve the shelf life of meat,probably as a result of a combined effect with dietary vitamin e.However,the recommended dietary inclusion levels depend on the polyphenol type and concentration and antioxidant capacity of the feedstuffs,which cannot be compared easily because no routine analytical grading methods are yet available.Unless phenolic compounds content in dietary ingredients/supplements for lambs are reported,no specific association with animal physiology responses may be established.

关键词： Fatty acid Forage Oilseed Polyphenol Vitamin e

Seasonal dynamics,kinetics,and effects of 2-hydroxyestradiol-17βon some steroidogenic enzymes in the ovary of the catfish Heteropneustes fossilis

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Aquaculture and Fisheries 2022年第5期7卷 462-473页

作者： Tapan Kumar Chourasia Radha Chaube Keerikkattil Paily joy Department of Zoology Institute of ScienceBanaras Hindu UniversityVaranasi221005India Hokkaido University Fisheries Sciences.3-1-1 Minato-ChoHakodateHokkaido041-8611Japan. Department of Biotechnology Cochin University of Science and TechnologyKochi682022India

The synthesis of bioactive steroids is catalyzed by an array of enzymes of diverse properties and actions.In the present study,seasonal dynamics and kinetics of key steroidogenic enzymes,17α-hydroxylase(Cyp17a),3β-hydroxysteroid dehydrogenase(Hsd3b),20α-hydroxysteroid dehydrogenase(Hsd20a)and 20β-hydroxysteroid dehydrogenase(Hsd20b)were investigated in the female catfish Heteropneustes fossilis.Further,the effects of the estrogen metabolite 2-hydroxyestradiol-17β(2-OHe2)and human chorionic gonadotropin(hCG)on activities of the above enzymes,cytochrome P450 aromatase(Cyp19a1),and steroid products including testosterone and cortisol were determined.The enzymes under investigation showed significant seasonal variations across the annual ovarian cycle with low activity in the gonad resting phase.The enzymes Hsd3b and Cyp17a showed high activity during early oogenesis but the activities of Hsd20a and Hsd20b were higher towards late oogenesis in the spawning phase.Hsd3b and Cyp17a elicited high apparent Km values(low substrate affinity)and high apparent Vmax in the vitellogenic phase compared to the postvitellogenic phase.Hsd20a did not elicit any significant differences in the kinetic parameters between the two phases.Hsd20b showed high apparent Km values(low substrate affinity)and high Vmax in the postvitellogenic phase.The incubation of ovarian slices with 2-OHe2 for 24 h increased dose-dependently Hsd3b,Cyp17a,Hsd20a and Hsd20b activities,similar to hCG.The levels of the corresponding C21 steroid products,progesterone(P4),17α-hydroxyprogesterone(17-OHP4),17,20α-dihydroxy-4-pregnen-3-one(17,20α-DP)and 17,20β-dihydoxy-4-pregnen-3-one(17,20β-DP),and cortisol were elevated.However,2-OHe2 decreased significantly the C19 and C18 steroids,testosterone and e2 levels,and Cyp19a activity.The co-incubation with hCG and 2-OHe2 produced a synergistic effect on the enzyme activities except that of CYP19a.The co-incubation reversed the inhibitory effect of 2-OHe2.The data show that 2-OHe2 exerts a dual role on steroidogenesis,sti

关键词： Catfish ovary Steroidogenic enzyme activity and kinetics 2-Hydroxyestradiol-17β Steroidogenic shift Human chorionic gonadotropin

Genetic differentiation between and within Northern Native American language groups:an argument for the expansion of the Native American CODIS database

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Forensic Sciences Research 2022年第4期7卷 662-672页

作者： Jessica A.Weise Jillian Ng Robert F.Oldt joy Viray Kelly L.McCulloh David Glenn Smith Sreetharan Kanthaswamy Forensic Science Graduate Program University of CaliforniaDavisCAUSA Molecular Anthropology Laboratory Department of AnthropologyUniversity of CaliforniaDavisCAUSA School of Mathematical and Natural Sciences Arizona State UniversityGlendaleAZUSA Sacramento County District Attorney’s Crime Laboratory SacramentoCAUSA California National Primate Research Center University of CaliforniaDavisCAUSA

The National Research Council recommends that genetic differentiation among subgroups of ethnic samples be lower than 3%of the total genetic differentiation within the ethnic sample to be used for estimating reliable random match probabilities for forensic use.Native American samples in the United States’Combined DNA Index System(CODIS)database represent four language families:Algonquian,Na-Dene,eskimo-Aleut,and Salishan.However,a minimum of 27 Native American language families exists in the US,not including language isolates.Our goal was to ascertain whether genetic differences are correlated with language groupings and,if so,whether additional language families would provide a more accurate representation of current genetic diversity among tribal populations.The 21 short tandem repeat(STR)loci included in the Globalfiler^(■)PCR Amplification Kit were used to characterize six indigenous language families,including three of the four represented in the CODIS database(i.e.Algonquian,Na-Dene,and eskimo-Aleut),and two language isolates(Miwok and Seri)using major population genetic diversity metrics such as F statistics and Bayesian clustering analysis of genotype frequencies.Most of the genetic variation(97%)was found to be within language families instead of among them(3%).In contrast,when only the three of the four language families represented in both the CODIS database and the present study were considered,4%of the genetic variation occurred among the language groups.Bayesian clustering resulted in a maximum posterior probability indicating three genetically distinct groups among the eight language families and isolates:(1)eskimo,(2)Seri,and(3)all other language groups and isolates,thus confirming genetic subdivision among subgroups of the CODIS Native American database.This genetic structure indicates the need for an increased number of Native American populations based on language affiliation in the CODIS database as well as more robust sample sets for those language families.

关键词： Forensic sciences population genetics Native Americans North America languages short tandem repeats(STRs or microsatellites)

PoreScript:Semi-automated pore size algorithm for scaffold characterization

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Bioactive Materials 2022年第7期7卷 1-8页

作者： Dana Jenkins Karim Salhadar Grant Ashby Anita Mishra joy Cheshire Felipe Beltran Melissa Grunlan Sebastien Andrieux Cosima Stubenrauch elizabeth Cosgriff-Hernandez Department of Biomedical engineering University of Texas–AustinAustinTX78712USA Department of Biomedical engineering Texas A&M UniversityCollege StationTX77843USA Universite de Strasbourg CNRSInstitut Charles Sadron UPR22F-67000StrasbourgFrance Institut für Physikalische Chemie Universitat StuttgartPfaffenwaldring 55D-70569StuttgartGermany

The scaffold pore size influences many critical physical aspects of tissue engineering,including tissue infiltration,biodegradation rate,and mechanical properties.Manual measurements of pore sizes from scanning electron micrographs using ImageJ/FIJI are commonly used to characterize scaffolds,but these methods are both time-consuming and subject to user bias.Current semi-automated analysis tools are limited by a lack of accessibility or limited sample size in their verification process.The work here describes the development of a new MATLAB algorithm,PoreScript,to address these limitations.The algorithm was verified using three common scaffold fabrication methods(e.g.,salt leaching,gas foaming,emulsion templating)with varying pore sizes and shapes to demonstrate the versatility of this new tool.Our results demonstrate that the pore size characterization using PoreScript is comparable to manual pore size measurements.The PoreScript algorithm was further evaluated to determine the effect of user-input and image parameters(relative image magnification,pixel intensity threshold,and pore structure).Overall,this work validates the accuracy of the PoreScript algorithm across several fabrication methods and provides user-guidance for semi-automated image analysis and increased throughput of scaffold characterization.

关键词： Pore size measurement Polymer scaffolds MATLAB program Tissue engineering

Knowledge Management Strategy for Handling Cyber Attacks in e-Commerce with Computer Security Incident Response Team (CSIRT)

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Journal of Information Security 2022年第4期13卷 294-311页

作者： Fauziyah Fauziyah Zhaosun Wang Gabriel joy School of Computer and Communication engineering University of Science and Technology Beijing Beijing China Faculty of economics and Business University of Indonesia Depok Indonesia

electronic Commerce (e-Commerce) was created to help expand the market share network through the internet without the boundaries of space and time. However, behind all the benefits obtained, e-Commerce also raises the issue of consumer concerns about the responsibility for personal data that has been recorded and collected by e-Commerce companies. The personal data is in the form of consumer identity names, passwords, debit and credit card numbers, conversations in email, as well as information related to consumer requests. In Indonesia, cyber attacks have occurred several times against 3 major e-Commerce companies in Indonesia. In 2019, users’ personal data in the form of email addresses, telephone numbers, and residential addresses were sold on the deep web at Bukalapak and Tokopedia. even though e-Commerce affected by the cyber attack already has a Computer Security Incident Response Team (CSIRT) by recruiting various security engineers, both defense and attack, this system still has a weakness, namely that the CSIRT operates in the aspect of handling and experimenting with defense, not yet on how to store data and prepare for forensics. CSIRT will do the same thing again, and so on. This is called an iterative procedure, one day the attack will come back and only be done with technical handling. Previous research has succeeded in revealing that organizations that have Knowledge Management (KM), the organization has succeeded in reducing costs up to four times from the original without using KM in the cyber security operations. The author provides a solution to create a knowledge management strategy for handling cyber incidents in CSIRT e-Commerce in Indonesia. This research resulted in 4 KM Processes and 2 KM enablers which were then translated into concrete actions. The KM Processes are Knowledge Creation, Knowledge Storing, Knowledge Sharing, and Knowledge Utilizing. While the KM enabler is Technology Infrastructure and People Competency.

关键词： Knowledge Management Cyber Security Computer Security Incident Response Team (CSIRT)

Climate Change Community-Based and ecosystem-Based Adaptation Strategies in Selected Coastal Barangays in Masinloc, Zambales, Philippines

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American Journal of Climate Change 2022年第4期11卷 342-362页

作者： Roann P. Alberto Annie Melinda Paz-Alberto Carl Dionelle B. Ponce Kimberly joy e. Mata Central Luzon State University Science City of Mu&#241 oz Nueva Ecija Philippines

Climate change continues to intensify existing disaster risks and vulnerabilities in the Philippines. Thus, implementation of climate change adaptation strategies is vital to counter the effects of climate change. It is in this context that this study was undertaken to analyze the need or urgency to adopt community and ecosystem-based adaptation strategies among selected coastal barangays (villages) of Masinloc, Zambales, Philippines. Various methods of data collection were utilized such as secondary data collection, primary data collection through household survey, key informant interviews, and focus group. Results of the study indicate that in terms of community-based adaptation strategies, all of the seven barangays in Masinloc have moderate necessity. However, only Barangays Bani and Collat have high adaptation capacity in terms of infrastructure and disaster preparedness. The execution of several community-based adaptation strategies helps these barangays to respond immediately and appropriately to the moderate risk posed by floods and storm surges. On the other hand, in terms of ecosystem-based adaptation strategies, all of the seven barangays have moderate necessity which implies that they have moderate vulnerability and risk to flood and storm surge but have high adaptation capacity in terms of the conservation and protection of coastal resources (mangroves and sea grasses). The barangays implemented the necessary ecosystem-based adaptation mechanisms that they might need in the future. This only means that when they are faced with disaster, the local communities are prepared to respond appropriately and to cope up with the effects of extreme weather events which lead to floods and storm surge. even though most of the ecosystem-based adaptation strategies are conducted by the seven barangays, there are several community-based adaptation strategies that are still lacking which will protect them from the effect of floods and storm surges. Hence, carrying out the missing adaptation strategies, both community

关键词： Climate Change Necessity Community-Based Adaptation Strategies ecosystem-Based Adaptation Strategies Disaster Risk Assessment

Morphologic Response of a River Channel to Sand Mining in River Tyaa,Kitui County,Kenya

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Journal of environmental & earth Sciences 2020年第2期2卷 12-18页

作者： Philip Gathogo Muiruri joy A.Obando Ishmail O.Mahiri Department of Geography Kenyatta UniversityKenya43844Nairobi

Over 40 billion tons of sand is mined worldwide every year which isestimated to be higher than the natural replacement rates. In Kenya, therate of sand mining is raising concerns over its environmental effects sinceit is not regulated. This paper presents findings on the geomorphic effectsof sand mining in the ephemeral River Tyaa channel in Kitui County. Thestudy adopts the concept of feedback response mechanism of a naturalgeomorphic system. Through purposive sampling River Tyaa was selectedfor the study, where rampant sand mining was reportedly taking place.Random sampling on the five sand mining sites identified came up with arepresentative site namely Kanginga on which systematic sampling wasapplied while collecting data at both the active and control sites. Dataon channel width, depth and slope angles was obtained through physicalmeasurements while data on quantity of sand mined was obtained fromMwingi Sand Mining Cooperative. Multiple logistic regression analysiswas used to analyse data whereby the model compared active and controlsites. Test results indicated that sand mining had significantly increasedriver channel’s width (O.R. =1.531), depth (O.R. =1.527) and slope angles(O.R. =1.634) at active mining sites compared to control sites as deducedfrom the respective Odds Ratios. It concluded that sand mining had alteredchannel’s morphology resulting to adverse environmental effects such asloss of riparian vegetation and channel incision. It recommended curbingof illegal sand mining through licencing operators and reducing quantity ofsand mined by closing some mines. Furthers, it recommended monitoringthrough regular environmental Impact Assessment (e.I.A) and Audit (e.A)to inform protection of the river system from degrading.

关键词： Channel incision ephemeral stream Morphologic response Sand mining Sustainable development