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Hospitalization dynamics during the first COVID-19 pandemic wave: SIR modelling compared to Belgium, France, Italy, Switzerland and New York City data

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Infectious Disease Modelling 2021年第1期6卷 398-404页

作者： gregory Kozyreff Optique Nonlineaire Theorique Universite libre de Bruxelles(U.L.B.)CP 231Belgium

Using the classical Susceptible-Infected-Recovered epidemiological model,an analytical formula is derived for the number of beds occupied by Covid-19 *** analytical curve is fitted to data in Belgium,France,New York City and Switzerland,with a correlation coefficient exceeding 98.8%,suggesting that finer models are unnecessary with such macroscopic *** fitting is used to extract estimates of the doubling time in the ascending phase of the epidemic,the mean recovery time and,for those who require medical intervention,the mean hospitalization *** variations can be observed among different outbreaks.

关键词： COVID-19 modelling Hospitalization Dynamics Pandemic Belgium SIR

Reduced texaphyrin:A ratiometric optical sensor for heavy metals in aqueous solution

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Frontiers of Chemical Science and Engineering 2020年第1期14卷 19-27页

作者： Harrison D.Root gregory Thiabaud Jonathan L.Sessler Department of Chemistry The University of Texas at AustinAustinTX 78712-1224USA

We report here a water-soluble metal cation sensor system based on the as-prepared or reduced form of an expanded porphyrin,*** metal complexation,a change in the redox state of the ligand occurs that is accompanied by a color change from red to *** long employed for synthesis in organic media,we have now found that this complexation-driven redox behavior may be used to achieve the naked eye detectable colorimetric sensing of several number of less-common metal ions in aqueous *** to In(Ⅲ),Hg(Ⅱ),Cd(Ⅱ),Mn(Ⅱ),Bi(Ⅲ),Co(Ⅱ),and Pb(Ⅱ)cations leads to a colorimetric response within 10 *** process is selective for Hg(Ⅱ)under conditions of competitive ***,among the subset of responseproducing cations,In(Ⅲ)proved unique in giving rise to a ratiometric change in the ligand-based fluorescence features,including an overall increase in *** cation selectivity observed in aqueous media stands in contrast to what is seen in organic solvents,where a wide range of texaphyrin metal complexes may be *** formation of metal cation complexes under the present aqueous conditions was confirmed by reversed phase highperformance liquid chromatography,ultra-violet-visible absorption and fluorescence spectroscopies,and highresolution mass spectrometry.

关键词： texaphyrin fluorescent sensor ion-sensing indium mercury

Forecast Hesitancy: Why are People Reluctant to Believe, Accept, or Respond to Various Weather, Water, and Climate Hazard-Related Forecasts?

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International Journal of Disaster Risk Science 2021年第4期12卷 600-609页

作者： Michael H.Glantz gregory E.Pierce Consortium for Capacity Building(CCB) Institute for Arctic and Alpine Research(INSTAAR)University of ColoradoBoulderCO80301USA

Current discussions of the social phenomenon of“vaccine hesitancy”with regard to Covid-19 provide an opportunity to use hesitancy as a means to shift thinking about untimely and delayed responses to forecasts of hydrometeorological ***,that is,provides a paradigm through which such regrettably delayed responses to hydromet hazards might be better understood and effectively *** exaggeration,just about every hydromet event provides an example of how hesitancy hinders individual,community,and national government risk-reducing preventive and mitigative responses to forecasts of foreseeable,relatively near-term climate,water,or weather *** for such hesitancy(for vaccine and forecast use alike)include—among others—lack of trust in the science,lack of confidence in government,and persistent concern about the uncertainties that surround forecasting—both meteorological and public *** such,a better understanding of the causes that lead to individual and group hesitancy can better inform hydromet forecasters and affected communities about ways in which beneficial actions in response to timely forecasts are often *** better understanding will facilitate,where necessary,targeted interventions to enhance the societal value of forecasting by reducing this long-observed challenge of“forecast hesitancy.”First,this article focuses on incidents of“vaccine hesitancy”that,for various reasons,people around the world are even now experiencing with regard to several now-available,and confirmed efficacious,Covid-19 *** of such incidents of indecisiveness first increased dramatically over the first few months of 2021,despite the strong scientific confidence that vaccination would significantly lower personal risk of contracting as well as spreading the ***,the notion of forecast hesitancy with regard to hydrometeorological hazards is discussed.

关键词： Disaster risk reduction Forecast Forecast hesitancy Hesitancy Hydromet hazards Vaccine hesitancy

The Black-winged Monarch(Monarcha frater):Geographic variation,taxonomy,a"new"population,and an enduring mystery in migration

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Avian Research 2023年第3期14卷 467-477页

作者： Leo Joseph Julian Teh Paul Sweet Phil gregory Australian National Wildlife Collection CSIRO National Research Collections AustraliaCanberra2601Australia American Museum of Natural History New YorkUSA Sicklebill Safaris TopazQueensland4885Australia

The Black-winged Monarch(Monarcha frater)inhabits low-mid elevation forests across New Guinea and far northeastern *** its four recognized subspecies,*** is migratory,breeding in tropical north-eastern Australia from approximately November–*** non-breeding range of ***,apart from some individuals overwintering in Australia,has been unknown for>100 *** from 194 New Guinean and Australian specimens and a literature review have not solved this mystery;the narrow latitudinal range of the intratropical migration may inhibit use of GPS loggers in resolving the migration *** work in central and western parts of southern New Guinea is *** data,however,revealed an essentially overlooked population in north-western New Guinea east of the Bird's Head Peninsula phenotypically indistinguishable from nominate *** of that *** genomic analysis of the complex will be largely done from toepad skin because frozen tissue samples for DNA analysis exist only of four individuals of what we suggest should be elevated to species rank as *** discuss how genomic analysis might distinguish among alternative taxonomic hypotheses of one,two or three *** suggest English names for what we consider to be three diagnosable taxa worth recognizing at species rank in this group:Arfak Monarch corresponding to ***(Bird's Head Peninsula and the“new”population of north-western New Guinea);Pearly Monarch for ***(Australia and still unknown non-breeding range),and Masked Monarch for ***(including kunupi,elsewhere in New Guinea).

关键词： Australia Migration monarch flycatcher Monarcha frater New Guinea Taxonomy

Association between Placental Malaria and Severe Pre-Eclampsia in Two University Hospitals of Yaounde City

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Open Journal of Obstetrics and Gynecology 2024年第9期14卷 1488-1511页

作者： Ayissi gregory Astrid Ruth Ndolo Kondo Ndoumba Afouba Alice Noa Ndoua Claude Cyrille Essiben Félix Meka Esther Belinga Etienne Metogo Junie Engo Engo Samuel Désiré Bodo Edmond Lemaire Tchente Nguefack Charlotte Foumane Pascal Mboudou Emile Télésphore Department of Obstetrics and Gynecology Faculty of Medicine and Biomedicals Sciences University of Yaound I Yaounde Cameroon Department of Obstetrics and Gynecology Faculty of Medicine and Pharmaceuticals Sciences University of Douala Douala Cameroon Department of Morphological and Anatomo-Pathological Sciences Faculty of Medicine and Pharmaceutical Sciences University of Dschang Dschang Cameroon. Department of Morphological and Anatomo-Pathological Sciences Faculty of Medicine and Biomedicals Sciences University of Yaound I Yaounde Cameroon

Context: Pre-eclampsia and placental malaria, are two diseases that share pathophysiological similarities, such as placental ischemia, endothelial dysfunction and production of pro-inflammatory cytokines. Objective: The objective of our study was to investigate the association between placental malaria lesions and severe pre-eclampsia. Methodology: We conducted a prospective analytical cross-sectional study in two University Hospitals in the city of Yaounde (Yaounde Central Hospital and the Gynaecological Obstetrics and Paediatrics Hospital), and in the laboratory of the Centre Pasteur in Yaounde over an eight-month period (1st January 2021 – 1st September 2021). All patients with pre-eclampsia diagnosed according to the criteria of the International Society for the Study of Hypertension (ISSHP) and free of chronic metabolic or infectious pathology were included in this study. The patients were divided into two groups: group 1 (mild pre-eclampsia) and group 2: severe pre-eclampsia. Socio-demographic, clinical and histopathological characteristics specific to pre-eclampsia and placental malaria were investigated. Statistical analysis was performed with SPSS 23.0 software, Chi 2 was used to compare categorical variables, Student t-test was used to compare means, and logistic regression was used to assess the association between placental malaria lesions and PES. Results: The mean age of our study population was 29.93 ± 7.36 years versus 28.28 ± 7.18 years in patients with mild and severe pre-eclampsia respectively. Pre-eclampsia placental lesions (accelerated villous maturation, infarction) were significantly greater in patients with severe pre-eclampsia (p Conclusion: Placental malaria lesions were significantly associated with severe pre-eclampsia and increased the risk of developing severe pre-eclampsia placental lesions by a factor of 10.

关键词： Mild Pre-Eclampsia Severe Pre-Eclampsia Malaria Placental Lesions Association

Single-Li^+ conductivity in ionomeric network

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Chinese Journal of Chemistry 1993年第5期11卷 429-434页

作者： FARRINGTON gregory C. Department of Materials and Engineer University of PennsylvaniaPhiladelphiaPA 19104USA

Ionomeric networks(IN)with lithium sulfate and sait-solvating oligo(oxyethylene)chain were synthesized on the purpose of improving the conductivity of single-Li^+-ionic ***^+-ionic conductivity depends considerably on the salt content of the INs although the apparent degree of cross- linking is fixed in a constant of 10 mol%.As salt content(Li/O value)equals 0.0467,conductivity of the IN containing neither small-molecular salt nor low molecular weight plasticizer reaches a maximum of 7×10^(-6) S/cm at 25℃.Temperature-conductivity relationship of the INs shows curved Arrhenins plots,suggesting that the ionic conduction is primarily influenced by segmental motion of the polymer *** addition,WLF(Williams-Landel-Ferry)equation is used to analyze the conductivity data, from which the related WLF parameters are determined.

关键词： Single-Li

Potential of the neonicotinoid imidacloprid and the oxadiazine indoxacarb for controlling five coleopteran pests of stored grain

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Insect Science 2012年第1期19卷 96-101页

作者： gregory J. Daglish Manoj K. Nayak Agri-Science Queensland Department of Employment Economic Development and Innovation Brisbane Queensland Australia

The potential for using imidacloprid （a neonicotinoid） and indoxacarb （an oxadiazine） as grain protectants was investigated in bioassays against resistant strains of five stored grain beetles. The species investigated were Rhyzopertha dominica （E）（the lesser grain borer）, Sitophilus oryzae （L.）（the rice weevil）, Tribolium castaneum （Herbst）（the rust-red flour beetle）, Oryzaephilus surinamensis （L.）（the saw tooth flour beetle）, and Cryptolestesferrugineus （Stephens）（the fiat grain beetle）. Each of these species has developed resistance to one or more protectants, including organophosphorus insecticides, synthetic pyrethroids and the juvenile hormone analogue methoprene. Mortality and re- production after a 2-week exposure of adults to treated wheat depended on species, dose and insecticide. Imidacloprid had no effect on S. oryzae at any dose, but none of the other species produced any live progeny at 10 mg/kg. Indoxacarb had no effect on T. castaneum at any dose, but none of the other species produced any live progeny at 5 mg/kg. The results show that although both imidacloprid and indoxacarb can control at least four of the five key pests tested at doses comparable to those used for organophosphorus protectants, more potent neonicotinoid or oxadiazine insecticides would be needed than either of these to provide broad spectrum protection of stored grain .

关键词： beetles imidacloprid indoxacarb stored grain

Simple glycolipids of microbes:Chemistry,biological activity and metabolic engineering

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Synthetic and Systems Biotechnology 2018年第1期3卷 3-19页

作者： Ahmad Mohammad Abdel-Mawgoud gregory Stephanopoulos Department of Chemical Engineering Massachusetts Institute of Technology77 Massachusetts Ave.CambridgeMA 02139USA

Glycosylated lipids(GLs)are added-value lipid derivatives of great *** their interesting surface activities that qualify many of them to act as excellent ecological detergents,they have diverse biological activities with promising biomedical and cosmeceutical ***,especially those of microbial origin,have interesting antimicrobial,anticancer,antiparasitic as well as immunomodulatory ***,GLs are hardly accessing the market because of their high cost of *** believe that experience of metabolic engineering(ME)of microbial lipids for biofuel production can now be harnessed towards a successful synthesis of microbial GLs for biomedical and other *** review presents chemical groups of bacterial and fungal GLs,their biological activities,their general biosynthetic pathways and an insight on ME strategies for their production.

关键词： Biosurfactant Glycolipids biosynthesis Glycosyl/acyl transferases Glycosides Physiological roles Lipid biotechnology

Proteasome inhibition-induces endoplasmic reticulum dysfunction and cell death of human cholangiocarcinoma cells

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World Journal of Gastroenterology 2007年第6期13卷 851-857页

作者： Yucel Ustundag Steven F Bronk gregory J Gores Mayo Clinic College of Medicine Rochester MN 55905 United States

AIM: To determine if proteasome inhibition induces apoptosis in human cholangiocarcinoma cells, and if so, to elucidate the cellular mechanisms. METHODS: Studies were performed in the human KMCH, KMBC, and Mz-ChA-1 cholangiocarcinoma, and normal rat cell lines. MG132, a peptide aldehyde, which inhibits the chymotrypsin-like activity of the proteaosome was employed for this study. Apoptosis was assessed morphologically by 4'-6-Diamidino-2-phenylindole (DAPI) nuclear staining and fluorescence microscopy. Mitochondrial membrane potential was examined using a fluorescent unquenching assay. Ultrastructural changes during cell death were examined using transmission electron microscopy (TEM). Caspase 3/7 activity was assessed using an enzymatic-based fluorescent assay. Cytosolic-free calcium concentrations were measured using Fura-2 and digitized fluorescent microscopy. RESULTS: MG132, a proteasome inhibitor, induced apoptosis in all the cholangiocarcinoma cell lines examined. In contrast, minimal cytotoxicity was observed in normal rat cholangiocytes. Apoptosis was time-and -concentration-dependent. There was no change in the mitochondrial membrane potential between treated and untreated cells. Ultrastructural examination by transmission electron microscopy displayed the classic features of apoptosis, but in addition, there was also dramatic vacuolization of the endoplasmic reticulum (ER). Unexpectedly, no increase in caspase 3/7 activity was observed in MG132 treated cells, nor did the pancaspase inhibitor, Q-VD-OPh prevent cell death. The protein synthesis inhibitor, cycloheximide, blocked apoptosis induced by proteosome inhibitor indicating that ER dysfunction was dependent upon the formation of new proteins. CONCLUSION: Proteosome inhibition induces ERdysfunction and caspase-independent cell death selectively in human cholangiocarcinoma cells. Proteasome inhibitors warrant evaluation as anticancer agents for the treatment of human cholangiocarcinoma.

关键词： MG132 Cholangiocarcinoma Proteosome Apoptosis Calcium