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An update on iron physiology

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World Journal of Gastroenterology 2009年第37期15卷 4617-4626页

作者： Manuel Muoz isabel Villar José Antonio García-Erce Transfusion Medicine School of Medicine University of Málaga Málaga 29071 Spain Department of Hospital Pharmacy University Hospital Miguel Servet Zaragoza 50009 Spain Hematology and Hemotherapy University Hospital Miguel Servet Zaragoza 50009 Spain

Iron is an essential micronutrient, as it is required for adequate erythropoietic function, oxidative metabolism and cellular immune responses. Although the absorption of dietary iron (1-2 mg/d) is regulated tightly, it is just balanced with losses. Therefore, internal turnover of iron is essential to meet the requirements for erythropoiesis (20-30 mg/d). Increased iron requirements, limited external supply, and increased blood loss may lead to iron deficiency (ID) and iron-deficiency anemia. Hepcidin, which is made primarily in hepatocytes in response to liver iron levels, inflammation, hypoxia and anemia, is the main iron regulatory hormone. Once secreted into the circulation, hepcidin binds ferroportin on enterocytes and macrophages, which triggers its internalization and lysosomal degradation. Thus, in chronic inflammation, the excess of hepcidin decreases iron absorption and prevents iron recycling, which results in hypoferremia and iron-restricted erythropoiesis, despite normal iron stores (functional ID), and anemia of chronic disease (ACD), which can evolve to ACD plus true ID (ACD + ID). In contrast, low hepcidin expression may lead to iron overload, and vice versa. Laboratory tests provide evidence of iron depletion in the body, or reflect iron-deficient red cell production. The appropriate combination of these laboratory tests help to establish a correct diagnosis of ID status and anemia.

关键词： Iron metabolism Iron deficiency Functionaliron deficiency, Hepcidin Anemia of chronic disease

Cell-type-specific memory consolidation driven by translational control

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Signal Transduction and Targeted Therapy 2021年第2期6卷 206-208页

作者： Qing Zhang isabel Bestard-Lorigados Weihong Song Townsend Family Laboratories Department of PsychiatryThe University of British ColumbiaVancouverBCCanada Institute of Aging School of Mental Health and Kangning HospitalThe Second Affiliated Hospital and Yuying Children’s HospitalWenzhou Medical UniversityWenzhouChina

***’s group has significantly contributed to the understanding of translational control in learning and *** a recent Nature article,they further reported the cell-typespecific translational control underlying memory consolidation.1 Long-term potentiation(LTP)has been widely acknowledged as one of the main cellular models of learning and ***,there are two components of LTP driven by different stimulations and *** early phase of LTP(E-LTP)and short-term memory(STM)are evoked for short periods and are temporary,relying primarily on modifications of pre-existing *** late phase of LTP(L-LTP)and consequent longterm memory(LTM)are elicited by strong and repetitive stimulation and are long-lasting,requiring new protein synthesis.

关键词： synthesis. translational stimulation

Two-tiered reconstruction of Late Pleistocene to Holocene changes in the freezing level height in the largest glacierized areas of the Colombian Andes

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Journal of Mountain Science 2022年第3期19卷 615-636页

作者： Daniel RUIZ-CARRASCAL Daniel GONZALEZ-DUQUE isabel RESTREPO-CORREA Department of Ecology Evolution and Environmental BiologyColumbia University in the City of New YorkNew YorkNY 10027USA Department of Civil and Environmental Engineering Vanderbilt University40024th Avenue South269 Jacobs HallNashville TN 3720USA Department of Earth Sciences Universidad EAFITCarrera 49 No.7Sur-50MedellínColombia

One way of deducing vertical shifts in the altitudinal distribution of Colombian high-altitude páramo environments is by inferring fluctuations in the height of the local freezing *** our research,we are implementing two complementary approaches to reconstruct Late Pleistocene to Holocene changes in the freezing level height(FLH)in two of the most extensively glacier-covered areas of the northern *** combined remote sensing and field-based geomorphological mapping with time-series reconstruction of changes in the altitude of the 0°C *** in the FLH were based on alreadypublished~30 kyr paleo-reconstructions of sea surface temperatures(SSTs)of the eastern tropical Pacific and the western tropical Atlantic,as well as on reconstructed long-term sea level changes and empirical orthogonal functions of present-day(historical)Indo-Pacific and tropical Atlantic SST *** also analyzed the probability distribution of air-sea temperature differences and the spatial distribution of grid points with SSTs above the minimum threshold necessary to initiate deep *** considered available historical nearsurface and free air temperature data of ERA-Interim reanalysis products,General Circulation Model(GCM)simulations,weather stations,and(deployed by our group)digital sensors,to assess the normal Environmental Lapse Rates(ELRs)at the regional to local *** combined maps of glacial landforms and our reconstructed FLHs provided us with a wellfounded inference of potential past glacier advances,narrowing down the coarse resolution of ice margins suggested by previous research *** extent of the areas with temperatures below the freezing point suggested here for the summits of our main study site exceeds in magnitude the corresponding glacier icecaps and front advances proposed by previous ***,our average lowest altitudes of the FLH for our comparative site are consistently above the main glacier-front advances previously su

关键词： Glacial events Colombian Andes Climate reconstruction Geomorphology Mountain glaciers Freezing level height

Common-path interferometric label-free protein sensing with resonant dielectric nanostructures

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Light(Science & Applications) 2020年第1期9卷 1086-1094页

作者： isabel Barth Donato Conteduca Christopher Reardon Steven Johnson Thomas F.Krauss Department of Physics University of YorkYO105DD YorkUK Department of Electronic Engineering University of YorkYO105DD YorkUK

Research toward photonic biosensors for point-of-care applications and personalized medicine is driven by the need for high-sensitivity,low-cost,and reliable *** the most sensitive modalities,interferometry offers particularly high performance,but typically lacks the required operational simplicity and ***,we introduce a common-path interferometric sensor based on guided-mode resonances to combine high performance with inherent *** sensor exploits the simultaneous excitation of two orthogonally polarized modes,and detects the relative phase change caused by biomolecular binding on the sensor *** wide dynamic range of the sensor,which is essential for fabrication and angle tolerance,as well as versatility,is controlled by integrating multiple,tuned structures in the field of *** approach circumvents the trade-off between sensitivity and dynamic range,typical of other phase-sensitive modalities,without increasing *** sensor enables the challenging label-free detection of procalcitonin,a small protein(13 kDa)and biomarker for infection,at the clinically relevant concentration of 1 pg mL^(−1),with a signal-to-noise ratio of *** result indicates the utility for an exemplary application in antibiotic guidance,and opens possibilities for detecting further clinically or environmentally relevant small molecules with an intrinsically simple and robust sensing modality.

关键词： dielectric integrating simplicity

A Concise Joint Transmit/Receive Antenna Selection Algorithm

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China Communications 2013年第3期10卷 91-99页

作者：王俊岭 Ana isabel Pérez-Neira 高梅国 School of Information and Electronics Beijing Institute of Technology Department of Signal Theory and Communications Universitat Politècnica de Catalunya

For reducing the computational complexity of the problem of joint transmit and receive antenna selection in Multiple-Input-Multiple-Output (MIMO) systems, we present a concise joint transmit/receive antenna selection algorithm. Using a novel partition of the channel matrix, we drive a concise formula. This formula enables us to augment the channel matrix in such a way that the computational complexity of the greedy Joint Transmit/Receive Antenna Selection (JTRAS) algorithm is reduced by a factor of 4n L , where n L is the number of selected antennas. A decoupled version of the proposed algorithm is also proposed to further improve the efficiency of the JTRAS algorithm, with some capacity degradation as a tradeoff. The computational complexity and the performance of the proposed approaches are evaluated mathematically and verified by computer simulations. The results have shown that the proposed joint antenna selection algorithm maintains the capacity perormance of the JTRAS algorithm while its computational complexity is only 1/4n L of that of the JTRAS algorithm. The decoupled version of the proposed algorithm further reduces the computational complexity of the joint antenna selection and has better performance than other decoupling-based algorithms when the selected antenna subset is small as compared to the total number of antennas.

关键词： MIMO systems antenna selection channel capacity

Evolution and Continuity of Linguistic Systems

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Language and Semiotic Studies 2022年第1期8卷 24-36页

作者： isabel Victoria Galleguillos Jungk Pontifical Catholic University of Sao Paulo University of Sao Paulo Brazil

In the inspiring extract highlighted in this paper,Saussure observes how the relation between the elements of the sign change and evolve over *** his Cours,he also details the elements of the linguistic sign and the principles governing them,defining language as a system of *** the natural resistance to changes in language in order to enable it to continually fulfill its function,that is,despite the necessary immutability of linguistic signs,they change over time,by being in constant contact with the communities of speakers,to whom language actually *** may seem paradoxical because language is composed of arbitrary relations between signified and signifier that seek to represent *** refers to a principle of change in language linked to a principle of *** present study focuses on the semiotic and communicational aspects of the development of linguistic systems in time,understood from a systemic *** is sought to evince how signs perpetuate themselves and evolve through their constant interaction with real communities of language *** approach can offer new insights about the continuity of linguistic systems as systems of signs that present immutable and mutable characters,and whose evolution can be understood based on open systems parameters,such as permanence,autonomy and sensitivity to flows of information,as studied by current theories and authors,showing that,to preserve its semiological life (CGL,1959,p.76),a living language must continuously reflect the purposes of its users.

关键词： linguistic systems linguistic mutability evolution continuity systems parameters

Oxidation of 4-chloro-3-methylphenol using zeolite Y-encapsulated iron(Ⅲ)-,nickel(Ⅱ)-,and copper(Ⅱ)-N,N'-disalicylidene-1,2-phenylenediamine complexes

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Chinese Journal of Catalysis 2016年第1期37卷 135-145页

作者： Solomon Legese Hailu Balachandran Unni Nair Mesfin Redi-Abshiro isabel Diaz Rathinam Aravindhan Merid Tessema 中央皮革研究所化工实验室亚的斯亚贝巴大学化学系催化与石油化学研究所

The degradation of 4-chloro-3-methylphenol（PCMC）using zeolite-encapsulated iron（III）,nickel（II）,and copper（II）complexes of N,N’-disalicylidene-1,2-phenylenediamine as catalysts,in a heterogeneous Fenton-like advanced oxidation process,was *** physicochemical properties of the catalysts were determined using powder X-ray diffraction,thermogravimetric analysis,Brunauer–Emmett–Teller surface area analysis,Fourier-transform infrared spectroscopy,elemental analysis,and scanning electron *** effects of four factors,namely initial H2O2 concentration,catalyst dosage,temperature,and pH,on the degradation of a model organic pollutant were *** results show that at low acidic pH,almost complete removal of PCMC was achieved with the iron（III）,nickel（II）,and copper（II）catalysts after 120 min under the optimum reaction conditions：catalyst dosage 0.1 g,H2O2 concentration 75 mmol/L,initial PCMC concentration 0.35mmol/L,and 50 °*** reusability of the prepared catalysts in PCMC degradation was also studied and a possible catalyst deactivation mechanism is *** possible intermediate products,degradation pathway,and kinetics of PCMC oxidation were also studied.

关键词： Ship-in-a-bottle method 4-Chloro-3-methylphenol Pseudo-first order Deactivation Hydroxyl radical

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World Journal of Gastroenterology 2022年第30期28卷 4231-4234页

作者： Manuel Muro Aurelia Collados-Ros isabel Legaz Immunology Service Instituto Murciano de investigación biosanitaria(IMIB)Hospital Clínico Universitario Virgen de la Arrixaca(HCUVA)Murcia 30120Spain Department of Legal and Forensic Medicine Biomedical Research Institute(IMIB)Regional Campus of International Excellence“Campus Mare Nostrum”Faculty of MedicineUniversity of MurciaMurcia 30100Spain

Alcohol intake is a risk factor for cancer development and metastatic disease *** vesicle(EV)-mediated interorgan communication is assumed to be significant in boosting tumorigenic pathways and disease *** research indicates that exosomes have a variety of roles in the development of cancer during pathophysiological *** involvement of EV signaling during cancer progression in the alcohol environment is ***,understanding communication networks and the role of EVs as biomarkers can contribute significantly to developing strategies to address the serious public health problems associated with alcohol consumption and cancer.

关键词： Exosomes Liver metastasis Alcohol-associated liver disease Cancer

The drama of memory in Shakespeare's history plays

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