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Persistent organic pollutants and chemicals of emerging Arctic concern in the Arctic environment

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Environmental Science and Ecotechnology 2024年第2期18卷 1-3页

作者： Yi-Fan Li roland Kallenborn Zifeng Zhang International Joint Research Center for Persistent Toxic Substances(IJRC-PTS) State Key Laboratory of Urban Water Resource and EnvironmentHarbin Institute of TechnologyHarbin 150090China International Joint Research Center for Arctic Environment and Ecosystem(IJRC-AEE) Polar AcademyHarbin Institute of Technology(PA-HIT)Harbin 150090China Heilongjiang Provincial Key Laboratory of Polar Environment and Ecosystem(HPKL-PEE) Harbin 150090China IJRC-PTS-NA TorontoONM2J 3N8Canada Faculty of Chemistry Biotechnology and Food Sciences(KBM)Norwegian University of Life Sciences(NMBU)NOe1433 AsNorway

Environmental pollutants,such as persistent organic pollutants(POPs),enter the Arctic mainly via long-range transport(LRT)through atmospheric and ocean/river *** the other hand,chemicals of emerging Arctic concern(CEACs)are often introduced as local contaminants from industrial,municipal,or infrastructure-related *** of their origins,all these contaminants negatively impact the health of the environment and the indigenous ***,in recent decades,the Arctic has been experiencing unprecedented climate *** combination of Arctic environmental changes and the introduction of new anthropogenic contaminants as chemical aids for exploiting Arctic resources led to a severe imbalance in the Arctic ***,an international consortium of Arctic experts asked for internationally coordinated actions to mitigate the serious problems that environmental pollution causes on Arctic ecosystems and people,according to the Berlin statement[1].

关键词： Arctic statement pollution

A Golden Touch in the Design of multifunctional Porphyrin metallacages:Host-Guest Chemistry for Drug-Target Interactions

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CCS Chemistry 2024年第7期6卷 1662-1671页

作者： Tamara Rodríguez-Prieto Darren Wragg Nicole Heiduk mihyun Park Nicole Strittmatter roland A.Fischer Angela Casini Guillermo moreno-Alcántar Chair of medicinal and Bioinorganic Chemistry Department of ChemistrySchool of Natural SciencesTechnical University of Munich85748 Garching b.München Professorship for Analytical Chemistry Department of ChemistrySchool of Natural SciencesTechnical University of Munich85748 Garching b.München Chair of Inorganic and metalOrganic Chemistry Department of ChemistrySchool of Natural SciencesTechnical University of Munich85748 Garching b.München munich Data Science Institute(mDSI) Technical University of Munich85748 Garching b.München

The use of three-dimensional self-assembled metallacages(mCgs)as multimodal drug platforms holds great ***,the synthesis of mCgs with increased complexity and functionality is a great challenge since understanding of the interaction of mCgs with biological targets is still *** this context,this work reports on the integration of a gold(III)porphyrin scaffold into a prismatic mCg structure and explores its application for multimodal therapy of cancer in vitro,namely enabling both photodynamic therapy and *** experimental approaches with a state-of-the-art metadynamics theoretical study,we discovered that the gold cage shows unprecedented host-guest interaction-driven selective stabilization of guanine-quadruplex(G4)structures-validated anticancer drug targets-disclosing a new mechanism to pursue in the design of supramolecular drugs.

关键词： gold metallacages porphyrins G4stabili-zation host-guestchemistry anticanceragents

Physico-Chemical and Structural Assessment of Akono Riparian Forest Watershed, Tributary of the Nyong Basin (Centre-Cameroon) at Different Stages of Degradation

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Journal of Environmental Protection 2024年第5期15卷 552-571页

作者： Nwamo roland Didier Gordon Nwutih Ajonina Ndzougou Nkodo Colette Rose Tomedi Eyango minette Department of management of Aquatic Ecosystems Institute of Fisheries and Aquatic Sciences at Yabassi University of Douala Yabassi Cameroon Cameroon Wildlife Conservation Society Mangrove & Coastal Wetlands Research Centre Mouanko Cameroon Department of Aquaculture Institute of Fisheries and Aquatic Sciences at Yabassi University of Douala Yabassi Cameroon

Freshwater bodies are natural resources that should be exploited to the fullest, while maintaining the sustainability of ecosystems and ecosystem services which they support. Riparian forests are more important as they contain rivers which are vital sources of fresh water for local populations. However, the quality and quantity of water issued from the watershed depend on the structural state of these forests. The aim of this work was to assess the physico-chemical and structural state of the Akono gallery forest. To achieve this, fieldwork consisted of selecting six major streams of the watershed including Ndjolong, menyeng adzap, Emomodo, mvila, Negbe and Ossoé kobok. On each of these, two stations, one intact and one degraded, were marked by transects. The method involved measuring Hydrometric parameters (depth, length, width) of the stream and Physico-chemical parameters of water in the streams while dendrometric parameters were measured along 100 m-transects laid using the point-centred quarter method modified for water bodies to collect tree, shrub and palm variables such as trunk diameter, crown diameter and height. macrophytes and species identification were carried out using standard botanical procedures. Results showed that, the majority of physico-chemical parameters measured differed significantly between intact and degraded stations (P Pentachletra mancrophylla, whereas on degraded sites, this index was low and characterized by the relative dominance of species Piptadeniastrum africanum. Sorensen’s index (0.56) and CFA showed that the different stands were homogeneous. We can affirm that the riparian forests of Akono watershed are towards a state of stability notwithstanding the perpetuation of anthropological actions.

关键词： Akono Gallery Forest Physico-Chemical Parameters Floristic Diversity Dendrometric Parameters

Assessment of Selenium Contamination in Sediments of the Aby and Tendo Lagoons in Côte d’Ivoire

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International Journal of Geosciences 2024年第4期15卷 334-349页

作者： Stéphane Jean Claon Kouakou Serge Kouassi Kossonou roland N’Guettia m’bassidjé Arsène Seka Guei Jokebed Dakouo Allico Joseph Djaman Kouakou Luc Kouadio Analytical Sciences and Public Health Department University of F&#233lix Houphou&#235t-Boigny Abidjan C&#244te d&#8217Ivoire Water Quality Control and Analysis Laboratory (LACQUE) Office National de l&#8217Eau Potable (ONEP) Abidjan C&#244te d&#8217Ivoire Biology and Health Laboratory University of F&#233lix Houphou&#235t-Boigny Abidjan C&#244te d&#8217Ivoire Laboratory of Environmental Sciences (LSE) University of Nangui Abrogoua Abidjan C&#244te d&#8217Ivoire Department of medical and Fundamental Biochemistry Institut Pasteur of C&#244te d&#8217Ivoire Abidjan C&#244te d&#8217Ivoire

Selenium is a trace element that can have both beneficial and harmful effects on aquatic life. The Aby Lagoon is a coastal environment in Côte d’Ivoire that receives selenium inputs from various natural and anthropogenic sources. The aim of this study was to assess the levels of selenium in the sediments of the Aby Lagoon and its tributaries, the Tanoe River and the Tendo Lagoon, and to examine the spatial and seasonal variations of selenium concentrations. Sediment samples were collected from different sites and seasons, and selenium concentrations were measured by atomic fluorescence spectrometry. The results showed that the average concentration of selenium in the sediments of the Aby Lagoon was 0.82 mg/kg, indicating moderate contamination. The concentration of selenium varied between sites and seasons, with higher values in the channel of the Tendo Lagoon and during the dry season. The study highlighted the complexity of selenium dynamics in aquatic ecosystems, and the need to take into account seasonal and spatial variability as well as interactions between environmental factors. The study also suggested potential ecotoxicological risks for some sensitive organisms in certain areas of the lagoon. This study contributes to the knowledge of the dynamics of selenium in lagoon ecosystems and to the assessment of the environmental risks associated with its presence.

关键词： Tropical Estuarine Selenium Sediments Aby Lagoon Seasonal Distribution

Assessment of Nitrates and Nitrites in Borehole Water from the Southern and the Northern Region of Côte d’Ivoire (West Africa)

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Open Journal of modern Hydrology 2024年第2期14卷 87-105页

作者： Jean Stéphane Claon Kouassi Kouakou Serge Sérikipré Laurent Seka m’Bassidjé Arsène N’Guettia Kossonou roland Traoré Aïcha Djamanallico Joseph Kouadio Kouakou Luc Analytical Sciences and Public Health Department University of Félix Houphou&#235t-Boigny Abidjan C&#244te d’Ivoire Water Quality Control and Analysis Laboratory (LACQUE) Office National de l’Eau Potable (ONEP) Abidjan C&#244te d’Ivoire Biology and Health Laboratory University of Félix Houphou&#235t-Boigny Abidjan C&#244te d’Ivoire Department of medical and Fundamental Biochemistry Institut Pasteur of C&#244te d’Ivoire Abidjan C&#244te d’Ivoire Laboratory of Environmental Sciences (LSE) University of Nangui Abrogoua Abidjan C&#244te d’Ivoire

This study aimed to evaluate the quality of water from village boreholes by measuring physicochemical parameters such as nitrates, nitrites, and total organic carbon (TOC). Forty-five (45) village pumps from the Southern (Basse Côte) and the Northern (Korhogo) region of Cte d’Ivoire (west Africa) were sampled. Physicochemical parameters such as temperature, pH, conductivity at 25˚C, and turbidity were determined in situ, while nitrite and nitrate were analyzed according to ISO 10304-1 (2007) standard and total organic carbon (TOC) by NF EN 1484 (1997) standard. The results showed that the borehole waters of the Basse Côte and Korhogo analyzed are acidic, with an average temperature of 27.51˚C ± 0.16˚C and 29.95˚C ± 0.51˚C respectively for the Basse Côte and Korhogo regions. The borehole waters of the Basse Côtedo not contain nitrites, while those of Korhogo have average nitrite contents of 0.32 mg/l. The average nitrate rate in the waters of the Basse Côte and Korhogo are 12.08 ± 2.11 mg/l and 11.03 ± 3.18 mg/l respectively. The average TOC concentration of the waters of the Basse Côte is 1.28 ± 0.32 mg/l and that of Korhogo is 0.56 ± 0.09 mg/L. The study showed that the borehole waters of the Basse Côte and Korhogo have average temperatures between 27.4˚C and 29.95˚C with a slightly acidic pH value and acceptable salinity. The TOC concentrations obtained at the different sampling points were all below the French standard (2 mg/L) except for certains pumps of the Basse Côte. The water samples from the Basse Côte were devoid of nitrite. On the other hand, those from Korhogo revealed the presence of nitrite. Also, the borehole waters of the regions of the Basse Côte and Korhogo contain relatively high nitrate contents, presumably due to anthropometric activity. Overall, our study on the quality of drinking water showed that the waters analyzed are in compliance with international standards and safe for consumption.

关键词： Drinking Water pH Turbidity TOC Nitrates Nitrites Health Effect

Impact of a national basic skills in colonoscopy course on trainee performance: An interrupted time series analysis

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World Journal of Gastroenterology 2020年第23期26卷 3283-3292页

作者： Keith Siau James Hodson John T Anderson roland valori Geoff Smith Paul Hagan marietta Iacucci Paul Dunckley Joint Advisory Group on Gastrointestinal Endoscopy Royal College of PhysiciansLondon NW14LEUnited Kingdom NIHR Biomedical Research Centre University of BirminghamBirmingham B152TTUnited Kingdom Institute of Translational medicine University Hospitals BirminghamBirmingham B152TTUnited Kingdom Department of Gastroenterology Gloucestershire Hospitals NHSFTCheltenham GL537ANUnited Kingdom Department of Gastroenterology Imperial College NHS Foundation TrustLondon NW14LEUnited Kingdom Endoscopy Department Derby Royal HospitalDerby GL13NNUnited Kingdom

BACKGROUND The Joint Advisory Group on Gastrointestinal Endoscopy basic skills in colonoscopy(BSC) course was introduced in 2009 to improve colonoscopy training within the United Kingdom, but its impact on trainee performance is *** To assess whether attendance of the BSC could improve colonoscopy *** Trainees awarded colonoscopy certification between 2011-2016 were stratified into 3 groups according to pre-course procedure count( 140).Study outcomes, comprising the unassisted caecal intubation rate(CIR) and the performance indicator of colonic intubation(PICI), were studied over the 50 procedures pre and post-course. Interrupted time series analyses were performed to detect step-change changes attributable to the *** A total of 369 trainees with pre-course procedure counts of 140(n = 130) were included. Over the 50 pre-course procedures,significant linear improvements in CIR were found, with average increases of 4.2,3.6 and 1.7 percentage points(pp) per 10 procedures performed in the 140 groups respectively(all P mprovement in CIR, increasing from 46% in the last pre-course procedure, to 51% in the first procedure post-course(P = 0.005). The CIR step-change was not significant in the 70-140(68% to 71%;P = 0.239) or > 140(86% to 87%;P = 0.354) groups. For PICI, significant step-change improvements were seen in all three groups, with average increases of 5.6 pp(P mprovement in PICI, regardless of prior procedural experience. However, CIR data suggest that the optimal timing of course attendance appears to be at earlier stages of training(< 70 procedures).

关键词： Colonoscopy Training Course Competency development Skills Endoscopy

metastatic Spinal Tumors: Diagnostic methods, management and Prognosis at the Yaounde Central Hospital and Yaounde General Hospital

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Open Journal of modern Neurosurgery 2024年第2期14卷 158-169页

作者： Nassourou Oumarou Haman Figuim Bello Orlane Ndome Toto roland Ndouh Nchufor Nya Durand Bakop Ronaldo Foalou Anu Vincent de Paul Djientcheu Faculty of medicine and Biomedical Sciences University of Yaounde 1 Yaounde Cameroon Neurosurgery Department Yaounde General Hospital Yaounde Cameroon Cameroon Academy of Young Scientists Yaounde Cameroon Department of Neurosurgery Garoua General Hospital Garoua Cameroon Faculty of medicine and Pharmaceutical Sciences University of Douala Douala Cameroon Department of Neurosurgery Douala General Hospital Douala Cameroon Facuty of Health Sciences University of Bamenda Bamenda Cameroon

Introduction: metastatic spinal tumors (mST) refer to secondary involvement of the vertebral column by hematogenously-disseminated metastatic cells. They could affect either the bony structures or the spinal cords. mechanical instability and neurologic deficits resulting from spinal cord compression are the most common manifestations. Surgical intervention remains the most effective treatment for about 20% of patients who present with spinal cord compression. The prognosis is relatively poor. This work has as objectives to describe: the diagnostic tools, the different modalities of management and the prognostic elements of spine metastasis. methodology: We conducted an ambispective cross-sectional descriptive study;with retrospective data collection from January 2015 to December 2021 and prospective collection from January to April 2022 in the “Neurosurgery” unit of the Yaounde Central Hospital and the “Oncology and Neurosurgery” units of Yaounde General Hospital. Result: We included 101 patients. The m/F sex ratio was 1.66. The average age of the participants was 56.44 years (±14.19 SD) with a median of 58 years. metastatic spinal tumors were discovered in 61.39% of patients with a previously known primary tumor and 21.78% of patients had newly discovered tumors. The neurologic examination revealed a vertebral syndrome in 79.21% of cases, radicular syndrome in 60.40% and sub-lesional syndrome in 59.89%. Sensory disorders accounted for 39.60% and sphincter disorders accounted for 34.65%. According to the degree of severity, the lesions were classified as Frankel E (37.62%) followed by Frankel D (21.78%). metastatic lesions were mostly found at the thoracic vertebrae (68.25%) and lumbar vertebrae (22.22%). The most represented primary tumors were: prostate tumors (41.58%) and breast tumors (23.76%);followed by malignant hemopathies (15.84%). Computed-tomography scan (CT-scan) was the most frequent diagnostic imaging technique used (71.28%). Analgesic treatment mostly

关键词： metastases Spinal Tumors Diagnosis Prognosis Spinal Cord Compression

Transient receptor potential channels as predictive marker and potential indicator of chemoresistance in colon cancer

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Oncology Research 2024年第1期32卷 227-239页

作者： WEI HU THOmAS WARTmANN mARCO STRECKER ARISTOTELIS PERRAKIS roland CRONER ARPAD SZALLASI WENJIE SHI ULF D.KAHLERT The Fourth Clinical medical College of Yangzhou University Nantong Rich HospitalNantongChina molecular and Experimental Surgery Clinic for General-Visceral-Vascular and Transplant SurgeryFaculty of Medicine and University Hospital MagdeburgOtto-von-Guericke UniversityMagdeburgGermany Department of Pathology and Experimental Cancer Research Semmelweis UniversityBudapestHungary

Transient receptor potential(TRP)channels are strongly associated with colon cancer development and *** study leveraged a multivariate Cox regression model on publicly available datasets to construct a TRP channels-associated gene signature,with further validation of signature in real world samples from our hospital treated patient ***-meier(K-m)survival analysis and receiver operating characteristic(ROC)curves were employed to evaluate this gene signature’s predictive accuracy and robustness in both training and testing cohorts,***,the study utilized the CIBERSORT algorithm and single-sample gene set enrichment analysis to explore the signature’s immune infiltration landscape and underlying functional *** support vector machine algorithm was applied to evaluate the signature’s potential in predicting chemotherapy *** findings unveiled a novel three TRP channels-related gene signature(mCOLN1,TRPm5,and TRPV4)in colon adenocarcinoma(COAD).The ROC and K-m survival curves in the training dataset(AUC=0.761;p=1.58e-05)and testing dataset(AUC=0.699;p=0.004)showed the signature’s robust predictive capability for the overall survival of COAD *** of the immune infiltration landscape associated with the signature revealed higher immune infiltration,especially an increased presence of m2 macrophages,in high-risk group patients compared to their low-risk ***-risk score patients also exhibited potential responsiveness to immune checkpoint inhibitor therapy,evident through increased CD86 and PD-1 expression ***,the TRPm5 gene within the signature was highly expressed in the chemoresistance group(p=0.00095)and associated with poor prognosis(p=0.036)in COAD patients,highlighting its role as a hub gene of ***,this signature emerged as an independent prognosis factor for COAD patients(p=6.48e-06)and expression of model gene are validated by public data a

关键词： Colon cancer Transient receptor potential channels Prognostic signature Chemotherapy efficiency TRPm5

Process Design for Hybrid Sheet metal Components

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Acta metallurgica Sinica(English Letters) 2015年第12期28卷 1518-1524页

作者： Rico Haase roland müller Dirk Landgrebe Peter Scholz matthias Riemer Fraunhofer Institute for machine Tools and Forming Technology IWU

The global trends towards improving fuel efficiency and reducing CO;emissions are the key drivers for lightweight solutions. In sheet metal processing, this can be achieved by the use of materials with a supreme strength-toweight and stiffness-to-weight ratio. Besides monolithic materials such as high-strength or light metals, in particular metal–plastic composite sheets are able to provide outstanding mechanical properties. Thus, the adaption of conventional, wellestablished forming methods for the processing of hybrid sheet metals is a current challenge for the sheet metal working industry. In this work, the planning phase for a conventional sheet metal forming process is studied aiming at the forming of metal–plastic composite sheets. The single process steps like material characterization, FE analysis, tool design and development of robust process parameters are studied in detail and adapted to the specific properties of metal–plastic composites. In material characterization, the model of the hybrid laminate needs to represent not only the mechanical properties of the individual combined materials, but also needs to reflect the behaviour of the interface zone between *** on experience, there is a strong dependency on temperature as well as strain rate. While monolithic materials show a moderate anisotropic behaviour, loads on laminates in different directions generate different strain states and completely different failure modes. During the FE analysis, thermo-mechanic and thermo-dynamic effects influence the temperature distribution within tool and work pieces and subsequently the forming behaviour. During try out and production phase,those additional influencing factors are limiting the process window even more and therefore need to be considered for the design of a robust forming process. A roadmap for sheet metal forming adjusted to metal–plastic composites is presented in this paper.

关键词： Characterization Hybrids Interface Layered structures Processing Sheet forming