3,667 research outputs found

    Human embryos from overweight and obese women display phenotypic and metabolic abnormalities

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    STUDY QUESTION Is the developmental timing and metabolic regulation disrupted in embryos from overweight or obese women? SUMMARY ANSWER Oocytes from overweight or obese women are smaller than those from women of healthy weight, yet post-fertilization they reach the morula stage faster and, as blastocysts, show reduced glucose consumption and elevated endogenous triglyceride levels. WHAT IS KNOWN ALREADY Female overweight and obesity is associated with infertility. Moreover, being overweight or obese around conception may have significant consequences for the unborn child, since there are widely acknowledged links between events occurring during early development and the incidence of a number of adult disorders. STUDY DESIGN, SIZE, DURATION We have performed a retrospective, observational analysis of oocyte size and the subsequent developmental kinetics of 218 oocytes from 29 consecutive women attending for ICSI treatment and have related time to reach key developmental stages to maternal bodyweight. In addition, we have measured non-invasively the metabolic activity of 150 IVF/ICSI embryos from a further 29 consecutive women who donated their surplus embryos to research, and have related the data retrospectively to their body mass index (BMI). PARTICIPANTS/MATERIALS, SETTING, METHODS In a clinical IVF setting, we compared oocyte morphology and developmental kinetics of supernumerary embryos collected from overweight and obese women, with a BMI in excess of 25 kg/m2 to those from women of healthy weight. A Primovision Time-Lapse system was used to measure developmental kinetics and the non-invasive COnsumption/RElese of glucose, pyruvate, amino acids and lactate were measured on spent droplets of culture medium. Total triglyceride levels within individual embryos were also determined. MAIN RESULTS AND THE ROLE OF CHANCE Human oocytes from women presenting for fertility treatment with a BMI exceeding 25 kg/m2 are smaller (R2 = −0.45; P = 0.001) and therefore less likely to complete development post-fertilization (P < 0.001). Those embryos that do develop reach the morula stage faster than embryos from women of a BMI < 25 kg/m2

    A systematic literature review comparing the psychological care needs of patients with mesothelioma and advanced lung cancer

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    © 2016 Elsevier LtdPurpose Psychological distress which adversely affects a person's experience of cancer has been shown to be highly prevalent in patients with mesothelioma. Historically, the assumption has been made that the evidence guiding the supportive care needs for lung cancer is relevant to those with mesothelioma. The objective of the study was to evaluate if the psychological care needs differ between patients with pleural mesothelioma and those with advanced lung cancer. Methods A search of MEDLINE, CINAHL, PsycARTICLES, Psychology and Behavioural Sciences Collection, PsycINFO databases, grey literature and the Cochrane Library of Systematic Reviews identified 17 studies meeting a predefined inclusion criteria. These were critically appraised for quality. Data relating to psychological experiences was extracted which was then synthesised narratively and through a process of meta ethnography. Results Common themes identified across the studies created 10 key concepts. These were uncertainty, normality, hope/hopelessness, stigma/blame/guilt, family/carer concern, physical symptoms, experience of diagnosis, iatrogenic distress, financial/legal and death and dying. Key similarities and differences were identified between the mesothelioma and lung cancer evidence. Conclusions There is limited research exploring the lived experiences of those with mesothelioma and lung cancer, with the majority of them having methodological and/or reporting concerns compromising the conclusions made. However, reoccurring themes in the evidence were found suggesting a number of areas where the psychological experience of mesothelioma differs from that of advanced lung cancer. These findings warrant further research to explore further and if proven, the need for the provision of specialist mesothelioma care services is affirmed

    A systematic literature review comparing the psychological care needs of patients with mesothelioma and advanced lung cancer

    Get PDF
    © 2016 Elsevier LtdPurpose Psychological distress which adversely affects a person's experience of cancer has been shown to be highly prevalent in patients with mesothelioma. Historically, the assumption has been made that the evidence guiding the supportive care needs for lung cancer is relevant to those with mesothelioma. The objective of the study was to evaluate if the psychological care needs differ between patients with pleural mesothelioma and those with advanced lung cancer. Methods A search of MEDLINE, CINAHL, PsycARTICLES, Psychology and Behavioural Sciences Collection, PsycINFO databases, grey literature and the Cochrane Library of Systematic Reviews identified 17 studies meeting a predefined inclusion criteria. These were critically appraised for quality. Data relating to psychological experiences was extracted which was then synthesised narratively and through a process of meta ethnography. Results Common themes identified across the studies created 10 key concepts. These were uncertainty, normality, hope/hopelessness, stigma/blame/guilt, family/carer concern, physical symptoms, experience of diagnosis, iatrogenic distress, financial/legal and death and dying. Key similarities and differences were identified between the mesothelioma and lung cancer evidence. Conclusions There is limited research exploring the lived experiences of those with mesothelioma and lung cancer, with the majority of them having methodological and/or reporting concerns compromising the conclusions made. However, reoccurring themes in the evidence were found suggesting a number of areas where the psychological experience of mesothelioma differs from that of advanced lung cancer. These findings warrant further research to explore further and if proven, the need for the provision of specialist mesothelioma care services is affirmed

    Unified dynamics of electrons and photons via Zitterbewegung and spin-orbit interaction

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    We show that when an electron or photon propagates in a cylindrically symmetric waveguide, it experiences both a Zitterbewegung effect and a spin-orbit interaction leading to identical propagation dynamics for both particles. Applying a unified perturbative approach to both particles simultaneously, we find that to first order in perturbation theory, their Hamiltonians each contain identical Darwin (Zitterbewegung) and spin-orbit terms, resulting in the unification of their dynamics. The presence of the Zitterbewegung effect may be interpreted physically as the delocalization of the electron on the scale of its Compton wavelength, or the delocalization of the photon on the scale of its wavelength in the waveguide. The presence of the spin-orbit interaction leads to the prediction of several rotational effects: the spatial or time evolution of either particle\u27s spin or polarization vector is controlled by the sign of its orbital angular momentum quantum number or, conversely, its spatial wave function is controlled by its spin angular momentum

    A Molecular Platinum Cluster Junction: A Single-Molecule Switch

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    We present a theoretical study of the electronic transport through single-molecule junctions incorporating a Pt6 metal cluster bound within an organic framework. We show that the insertion of this molecule between a pair of electrodes leads to a fully atomically engineered nano-metallic device with high conductance at the Fermi level and two sequential high on/off switching states. The origin of this property can be traced back to the existence of a HOMO which consists of two degenerate and asymmetric orbitals, lying close in energy to the Fermi level of the metallic leads. Their degeneracy is broken when the molecule is contacted to the leads, giving rise to two resonances which become pinned close to the Fermi level and display destructive interference.Comment: 4 pages, 4 figures. Reprinted (adapted) with permission from J. Am. Chem. Soc., 2013, 135 (6), 2052. Copyright 2013 American Chemical Societ

    Polymeric Bladder for Storing Liquid Oxygen

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    A proposed system for storing oxygen in liquid form and dispensing it in gaseous form is based on (1) initial subcooling of the liquid oxygen; (2) containing the liquid oxygen in a flexible vessel; (3) applying a gas spring to the flexible vessel to keep the oxygen compressed above the saturation pressure and, thus, in the liquid state; and (4) using heat leakage into the system for vaporizing the oxygen to be dispensed. In a typical prior system based on these principles, the flexible vessel is a metal bellows housed in a rigid tank, and the gas spring consists of pressurized helium in the tank volume surrounding the bellows. Unfortunately, the welds in the bellows corrugations are subject to fatigue, and, because bellows have large ullage, a correspondingly large fraction of the oxygen content cannot be expelled. In the proposed system, the flexible vessel would be a bladder made of a liquid- crystal polymer (LCP). (LCPs are strong and compatible with liquid oxygen.) In comparison with a metal bellows, a polymeric bladder would have less ullage and would weigh less. In experiments involving fatigue cycling at liquid-nitrogen temperatures, two LCPs were found to be suitable for this application

    Unequal relationships in high and low power distance societies: a comparative study of tutor - student role relations in Britain and China

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    This study investigated people's conceptions of an unequal role relationship in two different types of society: a high power distance society and a low power distance society. The study focuses on the role relationship of tutor and student. British and Chinese tutors and postgraduate students completed a questionnaire that probed their conceptions of degrees of power differential and social distance/closeness in this role relationship. ANOVA results yielded a significant nationality effect for both aspects. Chinese respondents judged the relationship to be closer and to have a greater power differential than did British respondents. Written comments on the questionnaire and interviews with 9 Chinese academics who had experienced both British and Chinese academic environments supported the statistical findings and indicated that there are fundamental ideological differences associated with the differing conceptions. The results are discussed in relation to Western and Asian concepts of leadership and differing perspectives on the compatibility/incompatibility of power and distance/closeness

    Cervical Cancer

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    This chapter in Cancer Concepts: A Guidebook for the Non-Oncologist presents provides an overview of cervical cancer. The etiology, pathology, staging, and principles of treatment will be reviewed.https://escholarship.umassmed.edu/cancer_concepts/1014/thumbnail.jp
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