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胎儿心音信号的数字分析

北京生物医学工程 1991年第4期10卷 202-208页

作者：周礼杲 Kartmann P. Nagel j. Schaldach m 清华大学电机系德国Erlangan大学

本文研究了胎儿第一心音与第二心音的频谱,比较了它们的特点.从而提出了分离第一心音与第二心音信号的频率滤波方法的设想.还提出了应用Hilbert交换由心音和心电测定射血前期的方案.探讨了研制胎儿心音监护仪的可能方案.

关键词：胎儿心音功率谱 Hilbert交换

Identification of Carbon Black in military Textiles Using Infrared Imaging Techniques

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Optics and Photonics journal 2013年第4期3卷 27-30页

作者： j. R. Andrés R. Hidalgo-Gato j. m. López-Higuera F. j. madruga Photonic Engineering Group University of Cantabria Santander Spain

The carbon black has been used in military fabrics to comply with the color requirements and infrared radiation lessening criteria. Currently, military industries don’t distinguish between fabrics with carbon black fibers or with carbon black into dyes or prints. The latter initially allows us to comply with the color specifications in the visible and infrared, but fabrics are degraded with use losing that initial capacity. The inclusion of carbon black in the fiber gets that the fabric doesn’t degrade with the wear, washed and dried, ensuring the accomplishment of the specifications all the time. The use of infrared imaging will allow us to define a method to discriminate those textiles with carbon black in their fibers from those which are dyed or printed.

关键词： military Textiles Fabrics Infrared Imaging Step-Heating Carbon Black Thermal Response

major Limb Amputations: Etiological and Clinical Profile in a Hospital in Sub-Saharan Africa

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Open journal of Orthopedics 2021年第2期11卷 40-46页

作者： S. Diao A. N. Kassé j. D. Diouf j. C. Sané B. Thiam m. B. Diallo m. H. Sy Department of Orthopedics and Trauma Surgery General Hospital Idrissa Pouye Dakar Sénégal

Introduction: During the 19th and 20th centuries, the Wars were the cause of many amputations among military and civilians. Despite the absence of armed conflict in our country, we notice a high frequency of major amputations in our activity. Objective: The aim of this work was to study the causes of major amputations observed in our practice in order to develop preventive measures. Materials and Method: This was a descriptive retrospective study over a 6-year period, from January 1, 2008 to December 31, 2014. The following parameters were studied: epidemiological aspects (age according to WHO age groups and gender of patients), type of amputation, level of amputation and causes. Results: Two hundred and fifty-two patients were included. The distribution of amputations by cause and age group showed two distinct entities: The forms of the young subject where there was a predominance of tumour and traumatic causes;and the forms of the elderly person caused by vascular infections and conditions. Infections were the main cause of amputation in both sexes. Conclusion: The causes of major limb amputations vary according to age and limb: tumor and trauma in young people and for the upper limb, infectious and vascular in the elderly and for the lower limb.

关键词： Diabetes Disarticulation Infections Limb major Amputation Tumors

The unfolded protein response signaling and retinal müller cell metabolism

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Neural Regeneration Research 2018年第11期13卷 1861-1870页

作者： Kristen Kelly joshua j.Wang Sarah X.Zhang Department of Ophthalmology and Neuroscience Program Ross Eye InstituteUniversity at BuffaloState University of New York SUNY Eye Institute State University of New YorkBuffaloNYUSA

The retina is one of the most energy demanding tissues in the body. Like most neurons in the central nervous system, retinal neurons consume high amounts of adenosine-5′-triphosphate（ATP） to generate visual signal and transmit the information to the brain. Disruptions in retinal metabolism can cause neuronal dysfunction and degeneration resulting in severe visual impairment and even blindness. The homeostasis of retinal metabolism is tightly controlled by multiple signaling pathways, such as the unfolded protein response（UPR）, and the close interactions between retinal neurons and other retinal cell types including vascular cells and müller glia. The UPR is a highly conserved adaptive cellular response and can be triggered by many physiological stressors and pathophysiological conditions. Activation of the UPR leads to changes in glycolytic rate, ATP production, de novo serine synthesis, and the hexosamine biosynthetic pathway, which are considered critical components of müller glia metabolism and provide metabolic support to surrounding neurons. When these pathways are disrupted, neurodegeneration occurs rapidly. In this review, we summarize recent advance in studies of the UPR in müller glia and highlight the potential role of the UPR in retinal degeneration through regulation of müller glia metabolism.

关键词： unfolded protein response retina müller glia metabolism neurodegeneration X-box binding protein 1 glycolysis glucose transporter

metabolomic studies in the inborn error of metabolism alkaptonuria reveal new biotransformations in tyrosine metabolism

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Genes & Diseases 2022年第4期9卷 1129-1142页

作者： Brendan P.Norman Andrew S.Davison juliette H.Hughes Hazel Sutherland Peter j.m.Wilson Neil G.Berry Andrew T.Hughes Anna m.milan jonathan C.jarvis Norman B.Roberts Lakshminarayan R.Ranganath George Bou-Gharios james A.Gallagher Institute of Life Course and medical Sciences University of LiverpoolWilliam Henry Duncan Building6 West Derby StreetLiverpoolL78TXUK Department of Clinical Biochemistry&metabolic medicine Liverpool Clinical LaboratoriesRoyal Liverpool University HospitalPrescot StreetLiverpoolL78XPUK School of Sport&Exercise Sciences Liverpool John Moores UniversityTom Reilly BuildingByrom StreetLiverpoolL33AFUK Department of Chemistry University of LiverpoolCrown StreetLiverpoolL697ZDUK

Alkaptonuria (AKU) is an inherited disorder of tyrosine metabolism caused by lack of active enzyme homogentisate 1,2-dioxygenase (HGD). The primary consequence of HGD deficiency is increased circulating homogentisic acid (HGA), the main agent in the pathology of AKU disease. Here we report the first metabolomic analysis of AKU homozygous Hgd knockout (Hgd−/−) mice to model the wider metabolic effects of Hgd deletion and the implication for AKU in humans. Untargeted metabolic profiling was performed on urine from Hgd−/− AKU (n = 15) and Hgd+/− non-AKU control (n = 14) mice by liquid chromatography high-resolution time-of-flight mass spectrometry (Experiment 1). The metabolites showing alteration in Hgd−/− were further investigated in AKU mice (n = 18) and patients from the UK National AKU Centre (n = 25) at baseline and after treatment with the HGA-lowering agent nitisinone (Experiment 2). A metabolic flux experiment was carried out after administration of 13C-labelled HGA to Hgd−/−(n = 4) and Hgd+/−(n = 4) mice (Experiment 3) to confirm direct association with HGA. Hgd−/− mice showed the expected increase in HGA, together with unexpected alterations in tyrosine, purine and TCA-cycle pathways. metabolites with the greatest abundance increases in Hgd−/− were HGA and previously unreported sulfate and glucuronide HGA conjugates, these were decreased in mice and patients on nitisinone and shown to be products from HGA by the 13C-labelled HGA tracer. Our findings reveal that increased HGA in AKU undergoes further metabolism by mainly phase II biotransformations. The data advance our understanding of overall tyrosine metabolism, demonstrating how specific metabolic conditions can elucidate hitherto undiscovered pathways in biochemistry and metabolism.

关键词： Alkaptonuria Biotransformation metabolism metabolomics mice

Stable gravastars： Guilfoyle＇s electrically charged solutions

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Chinese Physics C 2018年第11期42卷 120-130页

作者： Ayan Banerjee j.R. Villanueva Phongpichit Channuie Kimet jusufi Department of mathematics Jadavpur University Kolkata-700032 India Instituto de Fisica y Astronomia Facultad de Ciencias Universidad de Valparaiso Gran Bretana 1111 Valparaiso Chile School of Science Walailak University Nakhon Si Thammarat 80160 Thailand Physics Department State University of Tetovo Ilinden Street nn 1200 Macedonia

Compelling alternatives to black holes, namely, gravitational vacuum stars （gravastars）, which are multilayered compact objects, have been proposed to avoid a number of theoretical problems associated with event horizons and singularities. In this work, we construct a spherically symmetric thin-shell charged gravastar model where the vacuum phase transition between the de Sitter interior and the external Reissner-Nordstrom spacetime （RN） are matched at a junction surface, by using the cut-and-paste procedure. Gravastar solutions are found among the Guilfoyle exact solutions where the gravitational potential We and the electric potential field Ф obey a particular relation in a simple form a（b-εФ）^2＋b1, where a, b and bl are arbitrary constants. The simplest ansatz of Guilfoyle＇s solution is implemented by the following assumption： that the total energy density 8πρm＋Q^2/r^4 is constant, where Q（r） is the electric charge up to a certain radius r. We show that, for certain ranges of the parameters, we can avoid the horizon formation, which allows us to study the linearized spherically symmetric radial perturbations around static equilibrium solutions. To lend our solution theoretical support, we also analyze the physical and geometrical properties of gravastar configurations.

关键词： gravastar Guilfoyle exact solutions stability analysis

Evaluation of Daily Gridded meteorological Datasets over the Niger Delta Region of Nigeria and Implication to Water Resources management

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Atmospheric and Climate Sciences 2020年第1期10卷 21-39页

作者： Ibrahim Hassan Robert m. Kalin Christopher j. White jamiu A. Aladejana Department of Civil and Environmental Engineering University of Strathclyde Glasgow UK Department of Civil Engineering Abubakar Tafawa Balewa University Bauchi Nigeria Department of Geology University of Ibadan Ibadan Nigeria

Hydro-climatological study is difficult in most of the developing countries due to the paucity of monitoring stations. Gridded climatological data provides an opportunity to extrapolate climate to areas without monitoring stations based on their ability to replicate the Spatio-temporal distribution and variability of observed datasets. Simple correlation and error analyses are not enough to predict the variability and distribution of precipitation and temperature. In this study, the coefficient of correlation (R2), Root mean square error (RmSE), mean bias error (mBE) and mean wet and dry spell lengths were used to evaluate the performance of three widely used daily gridded precipitation, maximum and minimum temperature datasets from the Climatic Research Unit (CRU), Princeton University Global meteorological Forcing (PGF) and Climate Forecast System Reanalysis (CFSR) datasets available over the Niger Delta part of Nigeria. The Standardised Precipitation Index was used to assess the confidence of using gridded precipitation products on water resource management. Results of correlation, error, and spell length analysis revealed that the CRU and PGF datasets performed much better than the CFSR datasets. SPI values also indicate a good association between station and CRU precipitation products. The CFSR datasets in comparison with the other data products in many years overestimated and underestimated the SPI. This indicates weak accuracy in predictability, hence not reliable for water resource management in the study area. However, CRU data products were found to perform much better in most of the statistical assessments conducted. This makes the methods used in this study to be useful for the assessment of various gridded datasets in various hydrological and climatic applications.

关键词： Climate Research Unit (CRU) Princeton University Global meteorological Forcing Dataset (PGF) Climate Forecast System Reanalysis (CFSR) Standardised Precipitation Index (SPI)

Dispersal of the Zhujiang River(Pearl River) derived sediment in the Holocene

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Acta Oceanologica Sinica 2014年第8期33卷 1-9页

作者： GE Qian LIU j.P. XUE Zuo CHU Fengyou Key Laboratory of Submarine Geosciences State Oceanic AdministrationSecond Institute of OceanographyState Oceanic Administration Department of marine Earth and Atmospheric SciencesNorth Carolina State UniversityRaleighNC 27695USA

High-resolution Chirp profiling and coring reveals an elongated （ca. 400 km） Holocene Zhujiang River （Pearl River）-derived mud area （maximum thickness 〉 20 m） extending from the Zhujiang River Delta, southwest-ward off the Guangdong coast, to the Leizhou Peninsula. Two depo-centers, one proximal and one distal, are identified. On the continental shelf off the west Guangdong Province, the mud is deposited in water depth shallower than 50 m; while to the southeast of the Zhujiang River Estuary, the mud area can extend to the -120 m isobath. A combined analysis with the stratigraphic sequences of other muddy deposits in the West-ern Pacific marginal seas （mainly Changjiang （Yangtze） and Huanghe （Yellow） Rivers derived） indicates that the initiation of the Zhujiang River muddy deposit can be further divided into two stages： Stage 1 is before the mid-Holocene sea-level highstand （ca. 7.0 cal. ka BP）, the proximal mud was mostly deposited after 9.0 cal. ka BP, when the sea-level rose slowly after the meltwater Pulse -1C; Stage 2, after the mid-Holocene sea-level highstand, clinoform developed on the continental shelf off the west Guangdong Province, extending ca. 400 km from the Zhujiang River Estuary. The proximal clinoform thins offshore, from ca. 10 m thickness around 5-10 m water depth to less than 1-2 m around 20-30 m water depth. In addition, we also find a de-veloped distal clinoform in the east of the Leizhou Peninsula.

关键词： South China Sea Zhujiang River mud clinoform

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