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Health Risk Assessment of Heavy Metals in the Water of the LoutétéRiver, Mfouati District, Southeast Congo

Journal of Geoscience and Environment Protection 2022年第12期10卷 77-86页

作者： ifo grace mazel Diamouangana Mpissi Zita Flora Bibila Mafoumba Jean Claude Matini Laurent Laboratoire de Chimie Minérale et Appliquée Faculté des Sciences et Techniques Université Marien N’GOUABI Brazzaville Republic of the Congo Parcours chimie Faculté des Sciences et Techniques Université Marien N’GOUABI Brazzaville Republic of the Congo Département des Sciences Exactes Ecole Normale Supérieure Université Marien N’GOUABI Brazzaville Republic of the Congo Faculté des Sciences Appliquées Université DENIS SASSOU N’GUESSO Brazzaville Republic of the Congo

The overall objective of this study was to assess the health risk of water in the Loutété River contaminated with heavy metals. Six surface water samples were collected during the dry season (October 2014). The physico-chemical parameters (pH, electrical conductivity, total dissolved salts) were measured using a HANNA brand device. The values of these physico-chemical parameters are below the WHO standards. The concentrations of heavy metals Cr, Cu, Fe, Pb, Zn and Mn were determined by ICP-OES. These obtained in (μg/L) are in the range: Cr (0.08 - 5.8);Cu (0.6 - 14.5);Fe (0.2 - 386.05);Pb (1.02 - 370.09);Zn (8.02 - 248.7) and Mn (37.1 - 328.08). These concentrations are below the WHO drinking water guideline value in all samples for Cr, Cu, Mn and Zn, 50, 2000, 400 and 3000 μg/L respectively. Concentrations of As, Fe and Pb exceeded the WHO guideline value for drinking water at the following stations: S1 for arsenic, S4 for iron, and for Pb at all stations except S5. The health risk assessment for adults due to ingestion exposure gave HQing. values 1 for lead. In the case of ingestion, HQing. < 1 for the heavy metals Cr, Cu, Zn, Mn, with the exception of the following metals Arsenic, Lead and Iron.

关键词： Hazard Quotient Non-Carcinogenic Risk Heavy Metals

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Study of the Curing Temperature of 600°C, 700°C and 800°C of Mouyondzi Clay on the Mechanical, Physical and Microstructural Properties of Geopolymer Obtained

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Journal of Minerals and Materials Characterization and Engineering 2022年第2期10卷 185-197页

作者： Vezolo Stanislas ifo grace mazel Foutou Paul Mozalin Loubaki Raunel Diamouangana Zita Flora Moutou Joseph-Marie Laboratoire de Chimie Minérale et Appliquée Faculté des Sciences et Techniques Université Marien NGOUABI Brazzaville Republic of the Congo Faculté des Sciences et Techniques Université Marien NGOUABI Brazzaville Republic of the Congo Ecole Normale Supérieure Université Marien Ngouabi Brazzaville Republic of the Congo

This work consists of determining the right curing temperature for Mouyondzi clay, with a view to obtaining a very reactive metakaolinic amorphous phase, which will give us a geopolymer with good physical and mechanical performance. The kaolin-dominant Mouyondzi clay was calcined at 600℃, 700℃ and 800℃ with a heating rate of one degree per minute. In order to achieve the objective of this work, the performance of geopolymer was measured by compressive strength on geopolymer prisms of 28 days of age, by XRD and IRFT of geopolymer powders, calcined clay and raw clay, and by SEM of geopolymer blocks. Analysis of the results shows that the resistance value increases with the curing temperature of the clay and reaches a maximum of 49 MPa at 800℃. At 600℃ we already have 31 MPa, the equivalent of Portland cement with the addition. The XRD confirms the disappearance of clay species from 600℃. At 800℃ there is not yet the appearance of a new crystalline phase. Quartz is the only mineral species present. We can therefore confirm that at 800℃, the geopolymer obtained exhibits higher physical and mechanical performance than the other curing temperatures studied for Mouyondzi clay. This is confirmed by the appearance of a new aluminosilicate phase in the IRFT spectra and in the SEM images appearing as a continuous plate.

关键词： Geopolymer Compressive Strength Mouyonszi Clay Amorphous Phase

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Employing electrochemically derived pH gradients for Lab-on-PCB protein preconcentration devices

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Microsystems & Nanoengineering 2024年第1期10卷 79-87页

作者： grace Maxted Pedro Estrela Despina Moschou Department of Electronic and Electrical Engineering University of BathBath BA27AYUK Centre for Bioengineering and Biomedical Technologies(CBio) University of BathBath BA27AYUK

Protein preconcentration is an essential sample preparation step for analysis in which the targeted proteins exist in low concentrations,such as bodily fluids,water,or ***,very few practical implementations of miniaturized protein preconcentration devices have been demonstrated in practice,and even fewer have been integrated with other microanalytical *** approaches rely heavily on additional chemicals and reagents and introduce complexity to the overall *** this paper,we propose a novel miniaturized isoelectric focusing-based protein preconcentration screening device based on electrochemically derived pH gradients rather than existing chemical reagent *** this way,we reduce the need for additional chemical reagents to zero while enabling device incorporation in a seamlessly integrated full protein analysis microsystem via Lab-on-PCB *** apply our previously presented Lab-on-PCB approach to quantitatively control the pH of a solution in the vicinity of planar electrodes using electrochemical acid generation through redox-active self-assembled *** presented device comprises a printed circuit board with an array of gold electrodes that were functionalized with 4-aminothiophenol;this formed a self-assembled monolayer that was electropolymerized to improve its electrochemical *** preconcentration was performed in two *** first was open and needed the use of a holder to suspend a well of fluid above the electrodes;the second used microfluidic channels to enclose small volumes of *** here are the resulting data for protein preconcentration in both these forms,with a quantitative concentration factor shown for the open form and qualitative proof shown for the microfluidic.

关键词： electrochemical proof qualitative

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Relating estimates of wood properties of birch to stem form, age and species

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Journal of Forestry Research 2024年第3期35卷 1-11页

作者： grace Jones Maria Ulan Mateusz Liziniewicz Johan Lindeberg Stergios Adamopoulos Teagasc Forestry Development Department Ashtown Research CentreDublin 15 D15DY05Ireland Research Institutes of Sweden(RISE) GoteborgSweden The Forest Research Institute of Sweden(Skogforsk) Ekebo 225026890SvalovSweden Department of Forestry and Wood Technology Linnaeus University35195VaxjoSweden Department of Forest Biomaterials and Technology Swedish University of Agricultural SciencesBox 700875007 UppsalaSweden

Birch has long suffered from a lack of active forest management,leading many researchers to use mate-rial without a detailed management *** collected from three birch(Betula pendula Roth,*** Ehrh.)sites in southern Sweden were analyzed using regression analysis to detect any trends or differences in wood proper-ties that could be explained by stand history,tree age and stem *** sites were genetics trials established in the same *** of acoustic velocity(AV)from non-destructive testing(NDT)and predicted AV had a higher correlation if data was pooled across sites and other stem form factors were considered.A subsample of stems had radial profiles of X-ray wood density and ring width by year created,and wood density was related to ring number from the pith and ring *** seemed likely that wood density was negatively related to ring width for both birch *** models had slight improvements if site and species were included,but only the youngest site with trees at age 15 had both birch *** paper indicated that NDT values need to be considered separately,and any predictive models will likely be improved if they are specific to the site and birch species measured.

关键词： Acoustic velocity Non-destructive testing Predictive models Regression analysis Wood density

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Eco-ableism and access circularity in natural building

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Frontiers of Architectural Research 2024年第2期13卷 235-248页

作者： grace Schleck Lola Ben-Alon Barnard College Department of Architecture New YorkUSA Columbia University Graduate School of Architecture Planningand Preservation(GSAPP)New YorkUSA

The climate crisis disproportionately impacts disabled people. Yet climate-related advocacy, planning, and policymaking often neglect to thoughtfully include disabled people. Responding to this gap, disabled and neurodivergent environmental activists coined the term eco-ableism to describe discrimination and silencing toward disabled and neurodivergent people (i.e., ableism) arising in environmental spaces (i.e., eco-ableism). Relatedly, building operations and construction practices contribute a significant percentage of global, energy-related CO_(2) emissions annually, which calls into question the relationships between the impending climate crisis, disability justice, and architecture. Climate-specific, natural building materials and methods present a potential pathway toward a more sustainable built future: low-carbon, locally sourced, minimally processed, and nontoxic materials. Despite a critical overlap, there is little published research on material access in the production phase and human access in the occupation phase of natural buildings. Applying eco-ableism and material circularity in an architectural framework, this research aims to investigate the gaps and possibilities of access, natural material applications, and resulting US natural buildings informed by scholarship in critical disability studies and semi-structured interviews with natural building professionals.

关键词： Eco-ableism Critical disability studies Climate crisis and architecture Naturalmaterialsand methods

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An adaptive machine learning-based optimization method in the aerodynamic analysis of a finite wing under various cruise conditions

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Theoretical & Applied Mechanics Letters 2024年第1期14卷 27-34页

作者： Zilan Zhang Yu Ao Shaofan Li grace X.Gu Department of Mechanical Engineering University of CaliforniaBerkeley 94720USA Department of Engineering Peking UniversityBeijing 100871China Department of Civil and Environmental Engineering University of CaliforniaBerkeley 94720USA

Conventional wing aerodynamic optimization processes can be time-consuming and imprecise due to the complexity of versatile flight *** of existing literature has considered two-dimensional infinite airfoil optimization,while three-dimensional finite wing optimizations are subject to limited study because of high computational *** we create an adaptive optimization methodology built upon digitized wing shape deformation and deep learning algorithms,which enable the rapid formulation of finite wing designs for specific aerodynamic performance demands under different cruise *** methodology unfolds in three stages:radial basis function interpolated wing generation,collection of inputs from computational fluid dynamics simulations,and deep neural network that constructs the surrogate model for the optimal wing *** has been demonstrated that the proposed methodology can significantly reduce the computational cost of numerical *** also has the potential to optimize various aerial vehicles undergoing different mission environments,loading conditions,and safety requirements.

关键词： Aerodynamic optimization Computational fluid dynamics Radial basis function Finite wing Deep learning neural network

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Relative carcinogenicity of tacrolimus vs mycophenolate after solid organ transplantation and its implications for liver transplant care

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World Journal of Hepatology 2024年第4期16卷 650-660页

作者： Dorothy Liu Mark M Youssef Josephine A grace Marie Sinclair Department of Gastroenterology Austin HealthMelbourne 3084VictoriaAustralia Victorian Liver Transplant Unit Austin HealthMelbourne 3084VictoriaAustralia Department of Medicine University of MelbourneMelbourne 3084VictoriaAustralia

BACKGROUND De novo malignancy is a leading cause of late morbidity and mortality in liver transplant *** immunosuppression has been shown to contribute to post-transplant malignancy(PTM)*** is emerging evidence on the differential carcinogenic risk profile of individual immunosuppressive drugs,independent of the net effect of *** inhibitors such as tacrolimus may promote tumourigenesis,whereas mycophenolic acid(MPA),the active metabolite of mycophenolate mofetil,may limit tumour *** transplantation(LT)is relatively unique among solid organ transplantation in that immunosuppression monotherapy with either tacrolimus or MPA is often achievable,which makes careful consideration of the risk-benefit profile of these immunosuppression agents particularly relevant for this ***,there is limited clinical data on this subject in both LT and other solid organ transplant *** To investigate the relative carcinogenicity of tacrolimus and MPA in solid organ *** A literature search was conducted using MEDLINE and Embase databases using the key terms“solid organ transplantation”,“tacrolimus”,“mycophenolic acid”,and“carcinogenicity”,in order to identify relevant articles published in English between 1st January 2002 to 11th August *** terms,synonyms and explosion of MeSH terms,Boolean operators and truncations were also utilised in the *** lists of retrieved articles were also reviewed to identify any additional *** duplicates,abstracts from 1230 records were screened by a single reviewer,whereby 31 records were reviewed in ***-text articles were assessed for eligibility based on pre-specified inclusion and exclusion *** A total of 6 studies were included in this *** studies were large population registries or cohort studies,which varied in transplant era,type of organ transplanted and immunosuppression protocol us

关键词： Immunosuppression Solid organ transplantation Liver transplantation Carcinogenicity Tacrolimus Mycophenolate

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一门学科应该学习多长时间？

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中学生英语 2024年第25期 4-5页

作者： grace Fleming 苗淑华

How long should you study for a test? The answer to this question is different for everyone because it’s not just about how long you study—it’s also how effectively1you study. To study effectively, you should study at aproper2time.你应该为一次考试学习多长时间呢？这个问题的答案因人而异，因为它不仅关乎你学习的时间，还关乎你学习的效率。为了有效学习，你应该在适当的时间学习。

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Acute Colonic Pseudo-Obstruction (ACPO): An Expanding Colon with Unusual Risk Factors

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Open Journal of Internal Medicine 2024年第2期14卷 167-174页

作者： Kelly Schulte Alyson Terry grace Boyle Dmitriy Scherbak HCA Healthone Sky Ridge Medical Center Lone Tree Colorado USA

The distention of the colon without mechanical or anatomical obstruction, Acute Colonic Pseudo-obstruction (ACPO), is a common condition occurring in the critically ill. ACPO in the setting of an acute pulmonary embolism and embolic stroke is a rarity. A 76-year-old female with shortness of breath, left hemiparesis and right-sided paresthesias presented with acute pulmonary embolism and acute infarcts of the left caudate nucleus, thalamus and occipital lobe. Her hospitalization was complicated with persistent distention of the large bowel without dilation of the small bowel. Empiric antibiotics were initiated without improvement and laboratory studies including Clostridium difficile were negative. She underwent nasogastric decompression and two decompressive colonoscopies with a resolution of her symptoms. This case illustrates an example of acute abdominal distension, without underlying etiology, in the setting of acute embolism of the pulmonary and cerebral vasculature. Early identification and action with decompressive colonoscopy were key to preventing further bowel damage or rupture.

关键词： Acute Colonic Pseudo-Obstruction ACPO Ogilvie’s Syndrome Colonic Dilation Acute Embolic Infarcts Cerebrovascular Accident Pulmonary Embolism PE

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Contraceptive behaviors and awareness in an urban slum community of south India

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Asian pacific Journal of Reproduction 2024年第4期13卷 160-168页

作者： Monica Albert Sekhar Shanthi Edward Angeline grace Sushmitha G Shirley Esther Priscilla Department of Community Medicine Sree Balaji Medical College and Hospital(SBMCH)ChennaiIndia

Objective:To assess the factors associated with knowledge,attitude and behavior of contraception use among urban slum population in ***:A cross-sectional study was conducted in the urban slum of Anakaputhur,*** couples between ages of 19-49 years and living in slum areas were taken up for the study by simple random *** women,postnatal and postmenopausal women were excluded from the *** collection was done using a pretested structured questionnaire focusing on details regarding contraception knowledge,attitude,and *** analysis was done using IBM SPSS version *** test like Chi square and odds ratio(OR)were used to identify association between knowledge,attitude,and behavior of contraception with the associated variables and enter method of logistic regression analysis was ***:Out of the 360 respondents,228 were females,with a mean age of(34±5)*** 43%demonstrated adequate knowledge of contraception use,and 91%were aware of at least one contraceptive ***,72%exhibited a positive attitude towards contraceptive ***,43%(155 individuals)did not utilize any contraceptive *** contraceptive users,intrauterine devices were the most commonly adopted,followed by barrier methods and female *** was significant association between knowledge of contraception and education(aOR 7.29,95%CI 2.93-18.10,P<0.05),age(aOR 2.04,95%CI 1.19-3.50,P<0.05)and socioeconomic class(aOR 3.66,95%CI 1.71-7.85,P<0.05;aOR 3.97,95%CI 2.12-7.49,P<0.05).Regarding attitude towards contraception use,education(aOR 8.54,95%CI 2.35-31.03,P<0.05),sex(aOR 0.15,95%CI 0.06-0.37,P<0.05),age(aOR 0.53,95%CI 0.28-0.99,P<0.05),socio-economic class(aOR 4.42,95%CI 1.97-9.92,P<0.05;aOR 9.83,95%CI 3.63-26.58,P<0.05)and number of children(aOR 10.04,95%CI 4.26-23.66,P<0.05)were the variables that had a significant ***:These findings underscore the imperative for enhanced d

关键词： Family planning Unmet need Sterilization Knowledge Practice Urban slum

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