855 research outputs found

    Cauchy's residue theorem for a class of real valued functions

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    Let [a,b][a,b] be an interval in R\mathbb{R} and let FF be a real valued function defined at the endpoints of [a,b][a,b] and with a certain number of discontinuities within [a,b][a,b] . Having assumed FF to be differentiable on a set [a,b]\E[a,b] \backslash E to the derivative ff, where EE is a subset of [a,b][a,b] at whose points FF can take values ±∞\pm \infty or not be defined at all, we adopt the convention that FF and ff are equal to 0 at all points of EE and show that KH−vt∫abf=F(b)−F(a)\mathcal{KH-}vt\int_{a}^{b}f=F(b) -F(a)%, where KH−\mathcal{KH-} vtvt denotes the total value of the \textit{% Kurzweil-Henstock} integral. The paper ends with a few examples that illustrate the theory.Comment: 6 page

    Neonatal deaths in infants born weighing ≄ 2500 g in low and middle-income countries

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    Background: Babies born weighing ≄ 2500 g account for more than 80% of the births in most resource-limited locations and for nearly 50% of the 28-day neonatal deaths. In contrast, in high-resource settings, 28-day neonatal mortality among this group represents only a small fraction of the neonatal deaths. Yet mortality risks for birth weight of ≄ 2500 g is limited. Knowledge regarding the factors associated with mortality in these babies will help in identifying interventions that can reduce mortality.Methods: The Global Network\u27s Maternal Newborn Health Registry (MNHR) is a prospective, population-based observational study that includes all pregnant women and their pregnancy outcomes in defined geographic communities that has been conducted in research sites in six low-middle income countries (India, Pakistan, Democratic Republic of Congo, Guatemala, Kenya and Zambia). Study staff enroll all pregnant women as early as possible during pregnancy and conduct follow-up visits to ascertain delivery and 28-day neonatal outcomes. We analyzed the neonatal mortality rates (NMR) and risk factors for deaths by 28 days among all live-born babies with a birthweight ≄ 2500 g from 2010 to 2018 across the Global Network sites.Results: Babies born in the Global Network sites from 2010 to 2018 with a birthweight ≄ 2500 g accounted for 84.8% of the births and 45.4% of the 28-day neonatal deaths. Among this group, the overall NMR was 13.1/1000 live births. The overall 28-day NMR for ongoing clusters was highest in Pakistan (29.7/1000 live births) and lowest in the Zambian/Kenyan sites (9.3/1000) for ≄ 2500 g infants. ≄ 2500 g NMRs declined for Zambia/Kenya and India. For Pakistan and Guatemala, the NMR remained almost unchanged over the period. The ≄ 2500 g risks related to maternal, delivery and newborn characteristics varied by site. Maternal factors that increased risk and were common for all sites included nulliparity, hypertensive disease, previous stillbirth, maternal death, obstructed labor, severe postpartum hemorrhage, and abnormal fetal presentation. Neonatal characteristics including resuscitation, hospitalization, congenital anomalies and male sex, as well as lower gestational ages and birthweights were also associated with increased mortality.Conclusions: Nearly half of neonatal deaths in the Global Network sites occurred in infants born weighing ≄ 2500 g. The NMR for those infants was 13.1 per 1000 live births, much higher than rates usually seen in high-income countries. The changes in NMR over time varied across the sites. Even among babies born ≄ 2500 g, lower gestational age and birthweight were largely associated with increased risk of mortality. Since many of these deaths should be preventable, attention to preventing mortality in these infants should have an important impact on overall NMR.Trial registration: https://ClinicalTrials.gov Identifier: NCT01073475

    Permeability and conductivity of platelet-reinforced membranes and composites

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    We present large scale simulations of the diffusion constant DD of a random composite consisting of aligned platelets with aspect ratio a/b>>1a/b>>1 in a matrix (with diffusion constant D0D_0) and find that D/D0=1/(1+c1x+c2x2)D/D_0 = 1/(1+ c_1 x + c_2 x^2), where x=avf/bx= a v_f/b and vfv_f is the platelet volume fraction. We demonstrate that for large aspect ratio platelets the pair term (x2x^2) dominates suggesting large property enhancements for these materials. However a small amount of face-to-face ordering of the platelets markedly degrades the efficiency of platelet reinforcement.Comment: RevTeX, 5 pages, 4 figures, submitted to PR

    Data quality monitoring and performance metrics of a prospective, population-based observational study of maternal and newborn health in low resource settings

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    BACKGROUND: To describe quantitative data quality monitoring and performance metrics adopted by the Global NetworkÂŽs (GN) Maternal Newborn Health Registry (MNHR), a maternal and perinatal population-based registry (MPPBR) based in low and middle income countries (LMICs). METHODS: Ongoing prospective, population-based data on all pregnancy outcomes within defined geographical locations participating in the GN have been collected since 2008. Data quality metrics were defined and are implemented at the cluster, site and the central level to ensure data quality. Quantitative performance metrics are described for data collected between 2010 and 2013. RESULTS: Delivery outcome rates over 95% illustrate that all sites are successful in following patients from pregnancy through delivery. Examples of specific performance metric reports illustrate how both the metrics and reporting process are used to identify cluster-level and site-level quality issues and illustrate how those metrics track over time. Other summary reports (e.g. the increasing proportion of measured birth weight compared to estimated and missing birth weight) illustrate how a site has improved quality over time. CONCLUSION: High quality MPPBRs such as the MNHR provide key information on pregnancy outcomes to local and international health officials where civil registration systems are lacking. The MNHR has measures in place to monitor data collection procedures and improve the quality of data collected. Sites have increasingly achieved acceptable values of performance metrics over time, indicating improvements in data quality, but the quality control program must continue to evolve to optimize the use of the MNHR to assess the impact of community interventions in research protocols in pregnancy and perinatal health.Fil: Goudar, Shivaprasad S.. KLE University. Jawaharlal Nehru Medical College; IndiaFil: Stolka, Kristen B.. Research Triangle Institute International; Estados UnidosFil: Koso Thomas, Marion. Eunice Kennedy Shriver National Institute of Child Health and Human Development; Estados UnidosFil: Honnungar, Narayan V.. KLE University. Jawaharlal Nehru Medical College; IndiaFil: Mastiholi, Shivanand C.. KLE University. Jawaharlal Nehru Medical College; IndiaFil: Ramadurg, Umesh Y.. S. Nijalingappa Medical College; IndiaFil: Dhaded, Sangappa M.. KLE University. Jawaharlal Nehru Medical College; IndiaFil: Pasha, Omrana. Aga Khan University; PakistĂĄnFil: Patel, Archana. Indira Gandhi Government Medical College and Lata Medical Research Foundation; IndiaFil: Esamai, Fabian. University School of Medicine; KeniaFil: Chomba, Elwyn. University of Zambia; ZambiaFil: Garces, Ana. Universidad de San Carlos; GuatemalaFil: Althabe, Fernando. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas; Argentina. Instituto de Efectividad ClĂ­nica y Sanitaria; ArgentinaFil: Carlo, Waldemar A.. University of Alabama at Birmingahm; Estados UnidosFil: Goldenberg, Robert L.. Columbia University; Estados UnidosFil: Hibberd, Patricia L.. Massachusetts General Hospital for Children; Estados UnidosFil: Liechty, Edward A.. Indiana University; Estados UnidosFil: Krebs, Nancy F.. University of Colorado School of Medicine; Estados UnidosFil: Hambidge, Michael K.. University of Colorado School of Medicine; Estados UnidosFil: Moore, Janet L.. Research Triangle Institute International; Estados UnidosFil: Wallace, Dennis D.. Research Triangle Institute International; Estados UnidosFil: Derman, Richard J. Christiana Care Health Services; Estados UnidosFil: Bhalachandra, Kodkany S.. KLE University. Jawaharlal Nehru Medical College; IndiaFil: Bose, Carl L.. University of North Carolina; Estados Unido

    Long‐term follow‐up of stereotactic radiosurgery for head and neck malignancies

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    BackgroundStereotactic radiosurgery is widely applied to deliver additional dose to head and neck tumors. However, its safety and efficacy remains equivocal.MethodsOne hundred eighty‐four patients with primary head and neck cancers treated between January 1990 and August 2012 with Gamma Knife stereotactic radiosurgery were retrospectively reviewed.ResultsTwo hundred fifteen sites were treated with Gamma Knife stereotactic radiosurgery among 184 patients. Fifty‐one percent of patients received concurrent external beam radiotherapy (EBRT), 72% had prior surgery, and 46% received chemotherapy. Most (44%) had squamous cell carcinoma and most patients (65%) were treated for recurrent disease. With a median follow‐up of 17.3 months, 12‐month local control was 82%. Late effects occurred in 59 patients with the most common being temporal lobe necrosis (15 patients).ConclusionRadiosurgery can provide tumor control for patients with head and neck cancers involving the skull base. Long‐term follow‐up is important in survivors to identify late effects. © 2014 Wiley Periodicals, Inc. Head Neck 37: 1557–1562, 2015Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/115998/1/hed23798.pd
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