312 research outputs found

    High spin polarization and the origin of unique ferromagnetic ground state in CuFeSb

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    CuFeSb is isostructural to the ferro-pnictide and chalcogenide superconductors and it is one of the few materials in the family that are known to stabilize in a ferromagnetic ground state. Majority of the members of this family are either superconductors or antiferromagnets. Therefore, CuFeSb may be used as an ideal source of spin polarized current in spin-transport devices involving pnictide and the chalcogenide superconductors. However, for that the Fermi surface of CuFeSb needs to be sufficiently spin polarized. In this paper we report direct measurement of transport spin polarization in CuFeSb by spin-resolved Andreev reflection spectroscopy. From a number of measurements using multiple superconducting tips we found that the intrinsic transport spin polarization in CuFeSb is high (\sim 47\%). In order to understand the unique ground state of CuFeSb and the origin of large spin polarization at the Fermi level, we have evaluated the spin-polarized band structure of CuFeSb through first principles calculations. Apart from supporting the observed 47\% transport spin polarization, such calculations also indicate that the Sb-Fe-Sb angles and the height of Sb from the Fe plane is strikingly different for CuFeSb than the equivalent parameters in other members of the same family thereby explaining the origin of the unique ground state of CuFeSb.Comment: 6 pages, 4 figure

    New aspects and strategies for methane mitigation from ruminants.

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    The growing demand for sustainable animal production is compelling researchers to explore the potential approaches to reduce emissions of greenhouse gases from livestock that are mainly produced by enteric fermentation. Some potential solutions, for instance, the use of chemical inhibitors to reduce methanogenesis, are not feasible in routine use due to their toxicity to ruminants, inhibition of efficient rumen function or other transitory effects. Strategies, such as use of plant secondary metabolites and dietary manipulations have emerged to reduce the methane emission, but these still require extensive research before these can be recommended and deployed in the livestock industry sector. Furthermore, immunization vaccines for methanogens and phages are also under investigation for mitigation of enteric methanogenesis. The increasing knowledge of methanogenic diversity in rumen, DNA sequencing technologies and bioinformatics have paved the way for chemogenomic strategies by targeting methane producers. Chemogenomics will help in finding target enzymes and proteins, which will further assist in the screening of natural as well chemical inhibitors. The construction of a methanogenic gene catalogue through these approaches is an attainable objective. This will lead to understand the microbiome function, its relation with the host and feeds, and therefore, will form the basis of practically viable and eco-friendly methane mitigation approaches, while improving the ruminant productivity

    Association of bull semen protein estimates and SDS-PAGE profiles on semen freezability

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    It is vital to identify the ejaculate with good freezability by determining the biochemical makeup of the ejaculate at the pre-freeze stage. The present study targeted to assess the use of the protein estimates and profiles at the pre-freeze stage as markers of freezability in Frieswal populations. Storing the proteins for proteomic studies is always tricky in the case of animal studies, where accessibility to liquid nitrogen is limited. Hence alternative storing approaches need to be optimized. The second part of this study examined the protein concentration and protein profiles of RNALater and frozen stored sperm cells to assess the use of RNALater preservation in sperm proteomic studies. Sperm and seminal plasma protein concentrations were quantified using Bradford assay, and total protein quantities were derived. The seminal plasma and sperm protein profiles were generated with SDS-PAGE. The protein estimates and SDS-PAGE profiles of good and poor freeze-groups were similar. Also, sperm and seminal plasma protein concentration were not correlated with the semen volume and sperm count. Even though the yield was comparatively less, the protein profiles of sperm preserved by RNALater were similar to that of frozen sperms. The present study results indicate that the protein estimates and qualitative profiles of sperm and seminal plasma proteins may not be sufficient to reveal the differences in the proteome of good and poor freezable bulls at the macro level. Hence, the protein estimates and profiles of neat semen may not be helpful for the prediction of freezability at the pre-freeze stage. Secondly, this study indicates that RNALater preservation helps store sperms for proteome analysis studies

    Beyond Teenage and Young Adult Cancer Care: Care Experiences of Patients Aged 25-39 Years Old in the UK National Health Service.

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    AimsAdolescents and young adults aged 15-39 years with cancer face unique medical, practical and psychosocial issues. In the UK, principal treatment centres and programmes have been designed to care for teenage and young adult patients aged 13-24 years in an age-appropriate manner. However, for young adults (YAs) aged 25-39 years with cancer, little access to age-specific support is available. The aim of this study was to examine this possible gap by qualitatively exploring YA care experiences, involving patients as research partners in the analysis to ensure robust results.Materials and methodsWe conducted a phenomenological qualitative study with YAs diagnosed with any cancer type between ages 25 and 39 years old in the last 5 years. Participants took part in interviews or focus groups and data were analysed using inductive thematic analysis. Results were shaped in an iterative process with the initial coders and four YA patients who did not participate in the study to improve the rigor of the results.ResultsSixty-five YAs with a range of tumour types participated. We identified seven themes and 13 subthemes. YAs found navigating the healthcare system difficult and commonly experienced prolonged diagnostic pathways. Participants felt under-informed about clinical details and the long-term implications of side-effects on daily life. YAs found online resources overwhelming but also a source of information and treatment support. Some patients regretted not discussing fertility before cancer treatment or felt uninformed or rushed when making fertility preservation decisions. A lack of age-tailored content or age-specific groups deterred YAs from accessing psychological support and rehabilitation services.ConclusionsYAs with cancer may miss some benefits provided to teenagers and young adults in age-tailored cancer services. Improving services for YAs in adult settings should focus on provision of age-specific information and access to existing relevant support

    A retrospective analysis of clinical outcome of patients with chemo-refractory metastatic breast cancer treated in a single institution phase I unit

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    BACKGROUND AND METHODS: Novel approaches to treat chemo-refractory metastatic breast cancer (MBC) are currently under investigation. This retrospective series reviews the outcome of 70 MBC patients who have participated in 30 phase I trials at the Royal Marsden Hospital from 2002 to 2009. RESULTS: The median treatment lines before phase I trial entry for MBC was 5 (range: 1-12 lines). The overall response rate was 11.4% (95% CI: 4.0-18.9%) and the clinical benefit rate at 4 months was 20% (95% CI: 10.6-29.3). The median time to progression was 7.0 weeks (95% CI: 6.4-7.5) and median overall survival was 8.7 months (95% CI: 7.6-9.8) from start of first phase I treatment. No patients discontinued trial because of treatment-related toxicities. Abnormal lactate dehydrogenase, serum albumin <35 mg per 100 ml, >or=5 previous treatment lines, liver metastases and Eastern Cooperative Group performance status >or=2 at study entry were significantly associated with poor overall survival in multivariate analysis. CONCLUSION: This retrospective analysis provides evidence that patients with MBC tolerate phase I clinical trials and a significant proportion of patients with chemo-refractory disease, particularly those with triple-negative or Her2-positive breast cancer, may benefit from treatment

    Knowledge, Practice, and Attitudes of Physicians in Low- and Middle-Income Countries on Fertility and Pregnancy-Related Issues in Young Women With Breast Cancer

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    PURPOSE: Fertility and pregnancy-related issues are highly relevant for young ( 64 40 years) patients with breast cancer. Limited evidence exists on knowledge, practice, and attitudes of physicians from low- and middle-income countries (LMICs) regarding these issues. METHODS: A 19-item questionnaire adapted from an international survey exploring issues about fertility preservation and pregnancy after breast cancer was sent by e-mail between November 2019 and January 2020 to physicians from LMICs involved in breast cancer care. Descriptive analyses were performed. RESULTS: A total of 288 physicians from Asia, Africa, America, and Europe completed the survey. Median age was 38 years. Responders were mainly medical oncologists (44.4%) working in an academic setting (46.9%). Among responders, 40.2% and 53.8% reported having never consulted the available international guidelines on fertility preservation and pregnancy after breast cancer, respectively. 25.0%, 19.1%, and 24.3% of responders answered to be not at all knowledgeable about embryo, oocyte, or ovarian tissue cryopreservation, respectively; 29.2%, 23.6%, and 31.3% declared that embryo, oocyte, and ovarian tissue cryopreservation were not available in their countries, respectively. 57.6% of responders disagreed or were neutral on the statement that controlled ovarian stimulation can be considered safe in patients with breast cancer. 49.7% and 58.6% of responders agreed or were neutral on the statement that pregnancy in breast cancer survivors may increase the risk of recurrence overall or only in those with hormone receptor-positive disease, respectively. CONCLUSION: This survey showed suboptimal knowledge, practice, and attitudes of physicians from LMICs on fertility preservation and pregnancy after treatment completion in young women with breast cancer. Increasing awareness and education on these aspects are needed to improve adherence to available guidelines and to promote patients' oncofertility counseling

    Toward a theory of repeat purchase drivers for consumer services

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    The marketing discipline’s knowledge about the drivers of service customers’ repeat purchase behavior is highly fragmented. This research attempts to overcome that fragmented state of knowledge by making major advances toward a theory of repeat purchase drivers for consumer services. Drawing on means–end theory, the authors develop a hierarchical classification scheme that organizes repeat purchase drivers into an integrative and comprehensive framework. They then identify drivers on the basis of 188 face-to-face laddering interviews in two countries (USA and Germany) and assess the drivers’ importance and interrelations through a national probability sample survey of 618 service customers. In addition to presenting an exhaustive and coherent set of hierarchical repeat-purchase drivers, the authors provide theoretical explanations for how and why drivers relate to one another and to repeat purchase behavior. This research also tests the boundary conditions of the proposed framework by accounting for different service types. In addition to its theoretical contribution, the framework provides companies with specific information about how to manage long-term customer relationships successfully

    A diarylamine derived from anthranilic acid inhibits ZIKV replication

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    Zika virus (ZIKV) is a mosquito-transmitted Flavivirus, originally identified in Uganda in 1947 and recently associated with a large outbreak in South America. Despite extensive efforts there are currently no approved antiviral compounds for treatment of ZIKV infection. Here we describe the antiviral activity of diarylamines derived from anthranilic acid (FAMs) against ZIKV. A synthetic FAM (E3) demonstrated anti-ZIKV potential by reducing viral replication up to 86%. We analyzed the possible mechanisms of action of FAM E3 by evaluating the intercalation of this compound into the viral dsRNA and its interaction with the RNA polymerase of bacteriophage SP6. However, FAM E3 did not act by these mechanisms. In silico results predicted that FAM E3 might bind to the ZIKV NS3 helicase suggesting that this protein could be one possible target of this compound. To test this, the thermal stability and the ATPase activity of the ZIKV NS3 helicase domain (NS3Hel) were investigated in vitro and we demonstrated that FAM E3 could indeed bind to and stabilize NS3Hel
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