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Provenance of sediments from Barra del Tordo and Tesoro beaches, Tamaulipas state, northwestern Gulf of Mexico

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Journal of Palaeogeography 2021年第3期10卷 382-398页

作者： Mayla A.Ramos-Vazquez john s.Armstrong-Altrin Posgrado en Ciencias del Mar y Limnologpa Universidad Nacional Autonoma de MexicoCiudad UniversitariaCiudad de Mexico 04510Mexico Universidad nacional Autonoma de Mexico Instituto de Ciencias del Mar y LimnologiaUnidad de Procesos Oceanicos y CosterosCiudad UniversitariaCiudad de Mexico 04510Mexico

The mineralogy, bulk sediment geochemical composition, and U–Pb ages of detrital zircons retrieved from the Barra del Tordo(Tordo) and Tesoro beach sediments in the northwestern Gulf of Mexico were analyzed to determine their provenance. The beach sediments are mainly composed of quartz, ilmenite, magnetite, titanite,zircon, and anorthite. The weathering proxies such as the Chemical Index of Alteration(CIA), Chemical Index of Weathering(CIW), and Plagioclase Index of Alteration(PIA), reveal a moderate-to-high intensity of weathering in the source area. The chondrite-normalized rare earth element(REE) patterns are similar to felsic igneous rocks, with large negative europium anomaly(Eu/Eu^(*)= ~ 0.47–0.80 and ~ 0.57–0.67 in the Tordo and Tesoro beach sediments,respectively).Three major zircon U–Pb age groups are identified in the Tordo and Tesoro beach sediments, i.e., Proterozoic(~2039–595 Ma), Mesozoic(~ 244–70.3 Ma), and Cenozoic(~ 65.9–1.2 Ma). The differences of the zircon age spectrum between the Tordo and Tesoro beach sediments are not significant. The comparison of zircon U–Pb ages in this study with ages of potential source terranes suggests that the Mesozoic and Cenozoic zircons of the studied Tordo and Tesoro beach sediments were derived from the Eastern Alkaline Province(EAP) and Mesa Central Province(MCP). similarly, the likely sources for the Proterozoic zircons were the sierra Madre Oriental(sMOr) and Oaxaquia in the northwestern Gulf of Mexico. The results of this study further indicate that the sediments delivered to the beaches by rivers and redistributed by longshore currents were crucial in determining the sediment provenance.

关键词： Geochemistry sedimentary provenance Zircon U–Pb Beach sediment Rare earth elements Mexico

Impaired gluconeogenesis in a porcine model of paracetamol induced acute liver failure

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World Journal of Gastroenterology 2011年第11期17卷 1457-1461页

作者： Konstantinos J Dabos Henry R Whalen Philip n newsome john A Parkinson neil C Henderson Ian H sadler Peter C Hayes john n Plevris Liver Cell Biology Laboratory Department of HepatologyUniversity of EdinburghEdinburghEH16 4SAUnited Kingdom Gastroenterology Unit Ioannina General Hospital Hatzikosta450-01 IoanninaGreece Gastroenterology Department Hatzikosta General HospitalLeoforos Makrygianni450-01 IoanninaGreece Department of Chemistry University of EdinburghEdinburghEH16 6AAUnited Kingdom

AIM:To investigate glucose homeostasis and in particular gluconeogenesis in a large animal model of acute liver failure(ALF).METHODs:six pigs with paracetamol induced ALF under general anaesthesia were studied over 25 *** samples were withdrawn every five hours from a central *** animals were used as controls and were maintained under anaesthesia *** 1 H nMR spectroscopy we identified most gluconeogenic amino acids along with lactate and pyruvate in the animal plasma ***:no significant changes were observed in the concentrations of the amino acids studied in the animals maintained under anaesthesia *** we look at the ALF animals,we observed a statistically significant rise of lactate(Pnd pyruvate(Pnd of the *** also observed statistically significant rises in the concentrations of alanine(Pne(Pnine(Psine(Pnylalanine(Pnd isoleucine(Pne levels decreased significantly(PnCLUsIOn:Our pig model of ALF is characterized by an altered gluconeogenetic capacity,an impaired tricarboxylic acid(TCA)cycle and a glycolytic state.

关键词： Lactate Pyruvate Branch chain amino acids Aromatic amino acids

One Pot synthesis and Characterization of Cesium Doped snO_2 nanocrystals via a Hydrothermal Process

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Journal of Materials science & Technology 2012年第1期28卷 15-20页

作者： K.Kaviyarasu Prem Anand Devarajan s.stanly john Xavier s.Augustine Thomas s.selvakumar Department of Physics St.Xavier's CollegePalayamkottai 627002India Department of Chemistry St.Xavier's CollegePalayamkottai 627002India L.n.Govt.College Ponneri601204India

The physico-chemical properties of cesium doped snO2 nanocrystals synthesized by wet chemical method have been investigated. scanning electron microscopy （sEM）, X-ray diffraction （XRD）, energy dispersive X-ray analysis （EDAX）, inductively coupled plasma （ICP）, atomic absorption spectroscopic （AAs） analyses, UV-vis-nIR spectral studies and dielectric studies were carried out for both pure snO2 and cesium doped snO2 nano-samples. All samples of snO2 did not show any metallic cluster, but the sample containing cesium as a dopant displayed significant activity. The products formed were chloride and water representing a competitive advantage from the stand point of environmental protection.

关键词： Wet chemical Tin oxide (snO2) Cesium doped tin oxide (Cs:snO2) Inductivelycoupled plasma (ICP) Atomic absorption spectroscopy (AAs)

GDnF to the rescue:GDnF delivery effects on motor neurons and nerves,and muscle re-innervation after peripheral nerve injuries

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neural Regeneration Research 2022年第4期17卷 748-753页

作者： Alberto F.Cintrón-Colón Gabriel Almeida-Alves Juliana M.VanGyseghem john M.spitsbergen Biological sciences Department Western Michigan UniversityKalamazooMIUSA

Peripheral nerve injuries commonly occur due to trauma,like a traffic *** nerves get severed,causing motor neuron death and potential muscle *** current golden standard to treat peripheral nerve lesions,especially lesions with large(≥3 cm)nerve gaps,is the use of a nerve autograft or reimplantation in cases where nerve root avulsions *** not tended early,degeneration of motor neurons and loss of axon regeneration can occur,leading to loss of *** surgical procedures exist,patients often do not fully recover,and quality of life *** nerves have limited regeneration,and it is usually mediated by schwann cells and neurotrophic factors,like glial cell line-derived neurotrophic factor,as seen in Wallerian *** cell line-derived neurotrophic factor is a neurotrophic factor known to promote motor neuron survival and neurite *** cell line-derived neurotrophic factor is upregulated in different forms of nerve injuries like axotomy,sciatic nerve crush,and compression,thus creating great interest to explore this protein as a potential treatment for peripheral nerve *** glial cell line-derived neurotrophic factor has shown positive effects in regeneration and functional recovery when applied in experimental models of peripheral nerve *** this review,we discuss the mechanism of repair provided by schwann cells and upregulation of glial cell line-derived neurotrophic factor,the latest findings on the effects of glial cell line-derived neurotrophic factor in different types of peripheral nerve injuries,delivery systems,and complementary treatments(electrical muscle stimulation and exercise).Understanding and overcoming the challenges of proper timing and glial cell line-derived neurotrophic factor delivery is paramount to creating novel treatments to tend to peripheral nerve injuries to improve patients'quality of life.

关键词： electrical muscle stimulation exercise glial cell line-derived neurotrophic factor glial cell line-derived neurotrophic factor delivery motor neuron nerve gap neurotrophic factor peripheral nerve injury schwann cells skeletal muscle atrophy

Reactive Oxygen species and Oxidative stress in the Pathogenesis of MAFLD

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Journal of Clinical and Translational Hepatology 2022年第5期10卷 939-946页

作者： Kathleen Clare john F.Dillon Paul n.Brennan Royal Alexandra Hospital PaisleyNHS Greater Glasgow and ClydePA29PNUK University of Dundee Ninewells Hospital and Medical SchoolDundeeDD19SYUK University of Edinburgh Edinburgh BioQuarter5 Little France DriveEH164UUUK

The pathogenesis of metabolic-associated fatty liver disease(MAFLD)is complex and thought to be dependent on multiple parallel hits on a background of genetic *** evidence suggests that MAFLD progression is a dynamic two-way process relating to repetitive bouts of metabolic stress and inflammation interspersed with endogenous anti-inflammatory reparative *** MAFLD,excessive hepatic lipid accumulation causes the production of lipotoxins that induce mitochondrial dysfunction,endoplasmic reticular stress,and over production of reactive oxygen species(ROs).Models of MAFLD show marked disruption of mitochondrial function and reduced oxidative capacitance with impact on cellular processes including mitophagy,oxidative phosphorylation,and mitochondrial *** excess,ROs modify insulin and innate immune signaling and alter the expression and activity of essential enzymes involved in lipid *** can also cause direct damage to intracellular structures causing hepatocyte injury and *** select cases,the use of anti-oxidants and ROs scavengers have been shown to diminish the proapoptopic effects of fatty *** this link,endogenous anti-oxidant pathways have been a target of interest,with nrf2 activation showing a reduction in oxidative stress and inflammation in models of *** hormone receptorβ(THRβ)agonists and nuclear peroxisome proliferationactivated receptor(PPAR)family have also gained interest in reducing hepatic lipotoxicity and restoring hepatic function in models of ***,the true interplay between the clinical and molecular components of MAFLD progression remain only partly *** recently,multiomics-based strategies are being adopted for hypothesis-free analysis of the molecular changes in *** profiling maps the unique genotype-phenotype associations in MAFLD and with various single-cell tran scriptome-based projects underway,there is hope of novel physiological insigh

关键词： Fatty liver disease Metabolic-associated fatty liver disease nonalcoholic steatohepatitis Reactive oxidation species Oxidative stress

MR Imaging of Knee Osteoarthritis and Correlation of Findings with Reported Patient Pain

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Journal of Huazhong University of science and Technology(Medical sciences) 2010年第2期30卷 248-254页

作者：艾飞余铖张炜 john n Morelli Kacher D 李小明 Department of Radiology Tongji HospitalTongji Medical CollegeHuazhong University of Science and Technology Department of Radiology Scott & White Clinic and HospitalTexas A&M University Health Science Center Department of Radiology Brigham & Women's HospitalHarvard Medical School

summary： To evaluate lesion detection of MRI in knee joint osteoarthritis in patients with symptoms of pain, the correlation between MRI findings and varying degrees of reported pain was assessed. Twenty-eight patients （31 knees） with osteoarthritis were recruited for this study. The degree of knee pain was assessed by VRs scores. The knees were evaluated by plain film radiograph utilizing Kellgren-Lawrence scores. Multiple MR sequences were performed on a 1.5T MR-system, including sagittal and coronal dual fast spin echo （TRITE 3660/11/120 ms, slice thickness 5 mm）, coronal spin echo T1-weighted （TR/TE 360/9 ms, slice thickness 5 mm）, sagittal fat saturated 3D-spoiled gradient-recalled echo （TR/TE 50/6 ms; slice thickness 1.5 mm; flip angle 40°）, and 3D steady-state free precession （TR/TE 6/2.2 ms; slice thickness 1.6 mm; flip angle 30°） pulse sequences for the purpose of detecting abnormities of cartilage, menisci, the anterior cruciate ligaments, bone marrow edema-like lesions, osteophytes, synovitis, and joint effusions. MR findings were compared with the degree of pain using Fisher exact test with P values less than 0.05 indicating a statistically significant difference. The results showed that, of the 31 knees evaluated, mild pain was reported in 11 and severe pain in the remainder. Kellgren-Lawrence scores of all 31 evaluated OA knees were as follows： grade 1 lesions （n=6）, grade 2 lesions （n=14）, grade 3 lesions （n=8）, and grade 4 lesions （n=3）. Articular cartilaginous defects were found in 37.1% of knees. Abnormalities of the menisci and anterior cruciate ligaments, bone marrow edema-like lesions, osteophytes, synovitis, and joint effusions were detected in 32.3%, 38.7%, 45.2%, 100%, 15.1% and 67.7% of knees, respectively. Of these variables, only the differences in prevalence of joint effusions were significantly different in the mild and severe pain groups （P=0.004）. It is concluded that MRI evaluates the entire joint structure of the osteoarthritic knee,

关键词： knee osteoarthritis magnetic resonance imaging pain

Predictors of survival in autoimmune liver disease overlap syndromes

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World Journal of Hepatology 2024年第9期16卷 1269-1277页

作者： Dujinthan Jayabalan Yi Huang Luis Calzadilla-Bertot Malik Janjua Bastiaan de Boer john Joseph Wendy Cheng simon Hazeldine Briohny W smith Gerry C MacQuillan Michael C Wallace George Garas Leon A Adams Gary P Jeffrey Medical school University of Western AustraliaNed-lands 6009Western AustraliaAustralia Department of Hepatology Sir Charles Gairdner HospitalNedlands 6009Western AustraliaAustralia Department of Anatomical Pathology PathWest Laboratory MedicineNedlands 6009Western AustraliaAustralia Department of Gastroenterology and Hepatology Royal Perth HospitalPerth 6000Western AustraliaAustralia Department of Gastroenterology and Hepatology Fiona Stanley HospitalMurdoch 6150Western AustraliaAustralia Medical school University of Western AustraliaNedl-ands 6009Western AustraliaAustralia

BACKGROUnD survival in patients with autoimmune liver disease overlap syndromes(AILDOs)compared to those with single autoimmune liver disease is *** To investigate the survival of patients with AILDOs and assess the accuracy of non-invasive serum models for predicting liver-related *** Patients with AILDOs were defined as either autoimmune hepatitis and primary biliary cholangitis overlap(AIH-PBC)or autoimmune hepatitis and primary sclerosing cholangitis overlap(AIH-PsC)and were identified from three tertiary centres for this cohort ***-related death or transplantation(liver-related mortality)was determined using a population-based data linkage *** scores for liver-related death were compared for accuracy[including liver outcome score(LOs),Hepascore,Mayo score,model for end-stage liver disease(MELD)score and MELD incorporated with serum sodium(MELD-na)score].REsULTs Twenty-two AILDOs patients were followed for a median of 3.1 years(range,0.35-7.7).Fourteen were female,the median age was 46.7 years(range,17.8 to 82.1)and median Hepascore was 1(range,0.07-1).At five years post enrolment,57%of patients remained free from liver-related mortality(74%AIH-PBC,27%AIH-PsC).There was no significant difference in survival between AIH-PBC and *** was a significant predictor of liver-related mortality(Pn patients with AIH-PBC(n=14)but not AIH-PsC(n=8).A LOs cut-point of 6 discriminated liver-related mortality in AIH-PBC patients(P=0.012,log-rank test,100%sensitivity,77.8%specificity)(Harrell's C-statistic 0.867).The MELD score,MELD-na score and Mayo score were not predictive of liver-related mortality in any *** survival in the rare,AILDOs is *** current study supports the LOs as a predictor of liver-related mortality in AIH-PBC *** trials investigating predictors of survival in AILDOs are required.

关键词： Autoimmune liver disease overlap syndromes Liver outcome score Liver-related death Hepascore Autoimmune hepatitis Primary biliary cholangitis Primary sclerosing cholangitis

Emerging importance of shale gas to both the energy & chemicals landscape

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Journal of Energy Chemistry 2013年第1期22卷 21-26页

作者： john n. Armor GlobalCatalysis. Com L. L. C. 1608 Barkwood Dr.Orefield PA 18069 USA

This perspectives article is intended highlight the growing importance and emergence of shale gas as an energy resource and as a source of chemicals. Over the next decades huge amounts of newly discovered deposits of trapped gas are expected to be produced not only in the UsA but elsewhere providing a wealth of methane and ethane not only used for energy production, but also for conversion to lower hydrocarbon chemicals. This manuscript seeks to focus on the potential of trapped natural gas around the world. The potential new volumes of trapped gas within shale or other mineral strata coming to the marketplace offer a tremendous opportunity if scientists can invent new, cost effective ways to convert this methane to higher value chemicals. Understanding how to selectively break a single C-H bond in methane while minimizing methane conversion to C02 is critical.

关键词： applied catalysis: energy: shale gas chemical and petrochemical processes methane activation

Urban Plant Biomass Residues from the neotropics and Their Potential for Thermal Energy Generation

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Journal of Renewable Materials 2023年第9期11卷 3547-3566页

作者： john Freddy Gelves Díaz Ludovic Dorkis Richard Monroy-sepúlveda sandra Rozo-Rincón Gabriel de Jesús Camargo Vargas Competitiveness and sustainability for Development Research Group Faculty of EngineeringUniversidad Libre-Cúcuta SectionalCúcutaColombia Catalysis and nanomaterials Research Group Faculty of MinesUniversidad Nacional de Colombia-Medellín SectionalMedellínColombia Detecal Research Group Faculty of EngineeringUniversidad Libre-BogotáSectionalBogotáColombia

The material associated with tree pruning in a city in the Colombian neotropics was characterized in order to determine its energy *** species studied for their relevance in the territory were Prosopis juliflora,Licania tomentosa,Terminalia catappa,Azadirachta indica,Pithecellobium dulce,Ficus benjamina and Leucaena *** content,bulk density,hygroscopic response,elemental chemical analysis,proximal analysis,calorific value,ease of ignition and combustion,thermogravimetric and heat flow analysis,steam generation capacity,and qualitative analysis of gases(mass spectrometry)were *** results that were obtained show high initial moisture contents that vary between 37%and 67%and a variable density(when dry)between 0.21 and 0.41 g/***,it was shown that all residues have lower carbon and sulfur content compared to a reference mineral ***,the residues of some species have higher nitrogen contents compared to the same *** biomasses are characterized by their high content of volatile fractions and by having a lower content of inorganic matter compared to *** lower calorific values of these residues are between 14170 and 16928 kJ/kg,which are not negligible compared to other *** characteristic would be related to the high presence of hemicellulose in the *** gas monitoring revealed that there are different airflow needs in order to ensure complete *** generation tests showed that the calorific value should not be the most relevant criterion to establish the potential use of the waste,since leucaena leucocephala,despite having the highest calorific value,was the material with the lowest performance in steam generation.

关键词： Calorific value characterization combustion combustible material urban flora