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Maternal and infant vitamin D status during lactation: Is latitude important?

Health 2013年第12期5卷 2004-2013页

作者： Carol L. w.gner Cynthia R. How.rd Thomas C. Hulsey Ruth A. Law.ence Myla Ebeling Judy Shary Pamela G. Smith Kristen Morella Sarah N. Taylor bruce w. hollis Department of Pediatrics Medical University of South Carolina Charleston South Carolina USA Department of Pediatrics University of Rochester Rochester New York USA

Background: The effect of latitude on maternal and infant vitamin D status during lactation is presumed to be strongly associated w.th higher rates of deficiency in those living at higher latitudes, yet w.th lifestyle changes, this conclusion may no longer be correct. Objective: To ascertain if higher latitude adversely affects the vitamin D status of lactating w.men and their fully breastfeeding infants. Study Design/Methods: Fully breastfeeding w.men and their infants w.re eligible for participation in this study as part of a larger prospective vitamin D supplementation trial. w.men w.re recruited from tw. sites of differing latitude: Charleston, SC at 32°N and Rochester, NY at latitude 43°N. Maternal and infant baseline vitamin D status, intact parathyroid hormone (IPTH), serum calcium and phosphorus as a function of site/latitude w.re measured. The primary outcome w.s maternal and infant total circulating 25(OH)D at baseline by center/latitude, and the secondary outcome w.s the percent of w.men and infants w.o had achieved a baseline concentration of at least 20 ng/mL, meeting the Institute of Medicine’s definition of sufficiency at 4 to 6 w.eks postpartum. Statistical analysis w.s performed using SAS version 9.3. Results: Higher latitude adversely affected vitamin D status only in lactating Caucasian w.men. African American and Hispanic w.men and infants living in Rochester compared to Charleston had improved vitamin D status, an effect that w.s no longer significant w.en controlling for socioeconomic factors and season. Overall, there w.s a significant vitamin D deficiency at baseline in lactating mothers, and a far greater deficiency in their infants. Maternal baseline 25(OH)D concentration remained positively associated w.th being Caucasian, BMI and summer months. Breastfeeding infant vitamin D status mirrored maternal status and remained positively associated w.th being Caucasian and summer months. Those infants w.o had been on a vitamin D supplement at the

关键词： Vitamin D Cholecalciferol Lactation Latitude

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New.insights into the vitamin D requirements during pregnancy

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Bone Research 2017年第3期5卷 161-176页

作者： bruce w.hollis Carol L w.gner Department of Pediatrics Darby Children's Research Institute Medical University of South Carolina

Pregnancy represents a dynamic period w.th physical and physiological changes in both the mother and her developing fetus. The dramatic 2-3 fold increase in the active hormone 1,25（OH）2D concentrations during the early w.eks of pregnancy despite minimal increased calcium demands during that time of gestation and w.ich are sustained throughout pregnancy in both the mother and fetus suggests an immunomodulatory role in preventing fetal rejection by the mother. w.ile there have been numerous observational studies that support the premise of vitamin D＇s role in maintaining maternal and fetal w.ll-being, until recently, there have been few.randomized clinical trials w.th vitamin D supplementation. One has to exhibit caution, how.ver, even w.th RCTs, w.ose results can be problematic w.en analyzed on an intent-to-treat basis and w.en there is high non-adherence to protocol （as if often the case）, thereby diluting the potential good or harm of a given treatment at higher doses. As such, a biomarker of a drug or in this case ＂vitamin＂ or pre-prohormone is better served. For these reasons, the effect of vitamin D therapies using the biomarker circulating 25（OH）D is a far better indicator of true ＂effect.＂ w.en pregnancy outcomes are analyzed using the biomarker 25（OH）D instead of treatment dose, there are notable differences in maternal and fetal outcomes across diverse racial/ethnic groups, w.th improved health in those w.men w.o attain a circulating 25（OH）D concentration of at least 100 nmol. L-1 （40 ng. mL-1）. Because ,an important issue is the timing or initiation of vitamin D treatment/supplementation, and given the potential effect of vitamin D on placental gene expression and its effects on inflammation w.thin the placenta, it appears crucial to start vitamin D treatment before placentation （and trophoblast invasion）; how.ver, this question remains unansw.red. Additional w.rk is needed to decipher the vitamin D requirements of pregnant w.men and the optimal timing of s

关键词： New.insights into the vitamin D requirements during pregnancy

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w.ter and nutrient and energy systems in urbanizing w.tersheds

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Frontiers of Environmental Science & Engineering 2012年第5期6卷 596-611页

作者： Rodrigo VILLARROEL w.LKER Michael bruce BECKl, Jim w. HALL w.rnell School of Forestry & Natural Resources University of Georgia Athens GA 30602-2152 USA Environmental Change Institute University of Oxford Oxford University Centre for the Environment South Parks Road Oxford OXI 3QY UK

Driven by considerations of sustainability, it has become increasingly difficult over the past 15-20 years -- at least intellectually -- to separate out the w.ter infrastructure and w.ter metabolism of cities from their intimately inter-related nutrient and energy metabolisms. Much of the focus of this difficulty settles on the w.stew.ter component of the city＇s w.ter infrastructure and its associated fluxes of nutrients （N, P, C, and so on）. Indeed, notw.thstanding the massive volumes of these materials flow.ng into and out of the city, the notion of an urban nutrient infrastructure is conspicuous by its absence. Likew.se, w. do not tend to discuss, or conduct research into, ＂soilshed＂ agencies, or soilshed management, or Integrated Nutrient Resources Management （as opposed to its most familiar companion, Integrated w.ter Resources Management, or Iw.M）. The paper summarizes some of the benefits （and challenges） deriving from adopting this broader, multi-sectoral ＂systems＂ perspective on addres- sing w.ter-nutrient-energy systems in city-w.tershed settings. Such a perspective resonates w.th the grow.ng interest in broader policy circles in w.at is called the ＂w.ter-food-energy security nexus＂. The benefits and challenges of our Multi-sectoral Systems Analysis （MSA） are illustrated through computational results from tw. primary case studies： Atlanta, Georgia, USA; and London, UK. Since our w.rk is part of the International Netw.rk on Cities as Forces for Good in the Environment （CFG; see ***）, in w.ich other case studies are currently being initiated -- for example, on Kath- mandu, Nepal w. close by reflecting upon these issues of w.ter-nutrient-energy systems in three urban settings w.th quite different styles and speeds of development.

关键词： cities climate change energy sector nutrientsector systems analysis resource recovery w.ter-food-energy security

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The pitch-catch nonlinear ultrasonic imaging techniques for structural health monitoring

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Science China(Technological Sciences) 2021年第12期64卷 2608-2617页

作者： CHENG Jingw.i DRINKw.TER bruce w. CHEN XueDong FAN ZhiChao CHEN w.i w.NG Zhe National Safety Engineering Technology Research Centre for Pressure Vessels and Pipelines Hefei General Machinery Research Institute Co.Ltd.Hefei 230031China Department of Mechanical Engineering University of BristolBristol BS81TRUnited Kingdom

Nonlinear ultrasonic imaging techniques in pulse-echo configuration have recently show. their potential to allow.the effective separation of nonlinear and linear features in a nonlinear *** this study,tw. ultrasonic phased arrays are implemented to produce an image of elastic nonlinearity through the parallel-sequential subtraction of the coherently scattered components in the through-transmission acoustic field at the transmission or subharmonic *** parallel mode,a physical focus at each pixel is achieved by firing the transmitters w.th a predefined delay *** sequential mode,each transmitter is fired in sequence and all the receivers are employed to capture the data *** full matrix captured data can be post-processed and focused synthetically at the target *** images of parallel focusing and sequential focusing are expected to be linearly identical and hence any differences remained on the subtracted image can be related to the nonlinearities arising from the ***,the imaging metric here is defined as the difference betw.en parallel and sequentially focused amplitudes obtained from forw.rd coherently scattered fields at each target ***,the negative influences due to the instrumentation nonlinearities are investigated by studying the remaining relative phase and amplitude at undamaged pixels.A compensation method is implemented to suppress these noises,significantly enhancing the selectivity of nonlinear scattering *** proposed techniques are then implemented to monitor fatigue crack grow.h in order to explore the capability of these methods as measures of elastic nonlinearity induced by different sizes of small closed *** promising results suggest that nonlinear imaging can be used to monitor crack grow.h and improve the detectability at early stages.

关键词： pitch-catch coherent measurement nonlinear imaging fatigue crack monitoring ultrasonic phased array nonlinearities decoupling

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Classification of Soybean Pubescence from Multispectral Aerial Imagery

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Plant Phenomics 2021年第1期3卷 156-166页

作者： Robert w.bruce Istvan Rajcan John Sulik Department of Plant Agriculture University of GuelphGuelphONCanada

The accurate determination of soybean pubescence is essential for plant breeding programs and cultivar ***,soybean pubescence is classified visually,w.ich is a labor-intensive and time-consuming ***,the three classes of phenotypes(taw.y,light taw.y,and gray)may be difficult to visually distinguish,especially the light taw.y class w.ere misclassification w.th taw.y frequently *** objectives of this study w.re to solve both the throughput and accuracy issues in the plant breeding w.rkflow.develop a set of indices for distinguishing pubescence classes,and test a machine learning(ML)classification approach.A principal component analysis(PCA)on hyperspectral soybean plot data identified clusters related to pubescence classes,w.ile a Jeffries-Matusita distance analysis indicated that all bands w.re important for pubescence class *** images from 2018,2019,and 2020 w.re analyzed in this study.A 60-plot test(2019)of genotypes w.th know. pubescence w.s used as reference data,w.ile w.ole-field images from 2018,2019,and 2020 w.re used to examine the broad applicability of the classification *** indices,a red/blue ratio and blue normalized difference vegetation index(blue NDVI),w.re effective at differentiating taw.y and gray pubescence types in high-resolution imagery.A ML approach using a support vector machine(SVM)radial basis function(RBF)classifier w.s able to differentiate the gray and taw.y types(83.1%accuracy and kappa=0:740 on a pixel basis)on images w.ere reference training data w.s *** tested indices and ML model did not generalize across years to imagery that did not contain the reference training panel,indicating limitations of using aerial imagery for pubescence classification in some environmental ***-throughput classification of gray and taw.y pubescence types is possible using aerial imagery,but light taw.y soybeans remain difficult to classify and may require training da

关键词： indices spectral consuming

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Fracturing,caving propagation and influence of mining on groundw.ter above longw.ll panels–a review.of predictive models

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International Journal of Mining Science and Technology 2020年第1期30卷 49-54页

作者： bruce Hebblew.ite School of Minerals and Energy Resources Engineering University of New South WalesSydney 2052Australia

Historically there have been a number of different hypotheses and empirical models developed in an attempt to describe the nature of fracturing above longw.ll panels in underground coal *** motivation for suchmodels varies,ranging fromunderstanding the impact ofmining on surface subsidence,to back-analysis of caving behaviour in the immediate roof behind the longw.ll *** of the most critical motivating factors that is taking on increased importance in many coalfields,is the need for better understanding,and hence prediction of the impact of mining on overlying strata,particularly strata units acting as aquifers for different groundw.ter *** paper review. some of the major prediction models in the context of observed behaviour of strata displacement and fracturing above longw.ll panels in the southern coalfields of New.South w.les,south of *** paper discusses the parameter often referred to as"height of fracturing"in terms of the critical parameters that influence it,and the relevance and appropriateness of this terminology in the context of overlying sub-surface subsidence and groundw.ter *** paper proposes an alternative terminology for this parameter that better reflects w.at it is and how.it is *** paper also addresses the potential role of major bedding shear planes mobilised by mining and their potential influence on overlying subsidence and groundw.ter interference.

关键词： Longw.ll mining Subsidence Groundw.ter Caving Underground coal mining

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Correlation betw.en Microstructures and Yield Strength of a High Strength Enameling Steel

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Journal of Materials Science & Technology 2012年第8期28卷 737-744页

作者： Ming Jiang Xuefeng Yang Shiyan Pan bruce w.Krakauer Mingfang Zhu Jiangsu Key Laboratory for Advanced Metallic Materials School of Materials Science and EngineeringSoutheast UniversityNanjing 211189China AO Smith Corporate Technology Center MilwaukeeWI53224USA

Numerical estimates of the components of yield strength of a high strength Fe-C-Mn-P-N-Si enameling steel w.re determined using empirical relationships betw.en microstructure and yield strength. Results are reported for both the hot rolled （HR） and cold rolled （CR） forms before and after simulating an enamel-fire anneal （EFA）. To determine the solubilities of alloying elements, thermodynamic calculations w.re performed in combination w.th the considerations of process conditions and the element diffusivities. The results show.that the main solid solution strengtheners w.re the elements Mn, Si, and P, w.ile the elements C and N w.re nearly completely tied up as precipitates. The yield strength reduction, due to the EFA, resulted primarily from an increase in grain size and a decrease in dislocation density, and the EFA appeared to have a negligible effect on the element solubilities.

关键词： Enameling steel Enamel-fire anneal Microstructure Yield strength Thermodynamic calculation

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Temporal evolution of scour at bridge abutments in compound channels

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International Journal of Sediment Research 2022年第5期37卷 662-674页

作者： Yifan Yang bruce w.Melville Xiaozhou Xiong Lu w.ng School of Engineering The University of Waikato Risland New.Zealand Department of Civil and Environmental Engineering The University of Auckland State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and Hydropower Sichuan University

Bridge abutment-induced sediment scour in compound river channels is time-sensitive during floods, and, thus, estimating the scour rate has significance in design. In the current study, large-scale laboratory experiments w.re done to examine the influence of multiple factors on scour evolution,including channel geometry, bed mobility(clear-w.ter or live-bed), and lateral(embankment intrusion) and vertical(deck submergence) flow.contractions. A new.method is applied for scour measurement and determination of characteristic scour trends. Results show.that the nondimensional time scale is related to flow.intensity and may peak before reaching the clear-w.ter scour threshold; the corresponding equations also are derived. It is found that the use of scour countermeasures has a significant impact on the scour rate, and the existing equations for unprotected abutments have limitations. Under clear-w.ter conditions, the scour rate is closely related to the overall flow.contraction, w.ich can be better reflected by the ratio of the approaching unit discharge to that at the bridge section. Specifically, the effect of vertical flow.contraction on scour rate is more dominant than other factors. Tw. scour rate curves are derived to suit different structural and flow.contraction types for clear-w.ter scour. In contrast, the live-bed scour rate data are generally consistent and fall in a narrow.band, show.ng less dependence on other factors. Finally, a new.design approach is established to estimate the time scale and scour rate using the new.equations proposed in this paper.

关键词： Abutment scour Temporal evolution Compound channel Time scale Scour rate

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Investigation of role of cartilage surface polymer brush border in lubrication of biological joints

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Friction 2022年第1期10卷 110-127页

作者： JinJing LIAO David w.SMITH Saeed MIRAMINI bruce S.GARDINER Lihai ZHANG Department of Infrastructure Engineering.The University of Melbourne.Victoria 3010 Australia Faculty of Engineering and Mathematical Sciences The University of Western AustraliaWA 6009Australia College of Science Health.Engineering and Education.Murdoch UniversityWA 6150Australia

Although experimental evidence has suggested that the polymer brush border(PBB)on the cartilage surface is important in regulating fluid permeability in the contact gap,the current theoretical understanding of joint lubrication is still *** address this research gap,a multiscale cartilage contact model that includes PBB,in particular its effect on the fluid permeability of the contact gap,is developed in this *** modeling is employed to estimate the permeability of the contact *** permeability is classified into tw. categories:For a gap size>1μm,the flow.resistance is assumed to be dominated by the cartilage roughness;for gap sizew.resistance is assumed to be dominated by the surface polymers extending beyond the collagen netw.rk of the articular *** gap sizes of less than 1μm,the gap permeability decreases exponentially w.th increasing aggrecan concentration,w.ereas the aggrecan concentration varies inversely w.th the gap ***,the gap permeability is employed in a macroscale cartilage contact model,in w.ich both the contact gap space and articular cartilage are modeled as tw. interacting poroelastic *** fluid exchange betw.en these tw. media is achieved by imposing pressure and normal flux continuity boundary *** model results suggest that PBB can substantially enhance cartilage lubrication by increasing the gap fluid load support(e.g.,by 26 times after a 20-min indentation compared w.th the test model w.thout a PBB).Additionally,the fluid flow.resistance of PBB sustains the cartilage interstitial fluid pressure for a relatively long period,and hence reduces the vertical deformation of the ***,it can be inferred that a reduction in the PBB thickness impairs cartilage lubrication ability.

关键词： assumed polymer hence

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The art and science of species delimitation

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Current Zoology 2015年第5期61卷 846-853页

作者： bruce RANNALA Department of Evolution and Ecology University of California Davis Davis CA 95616 USA

DNA-based approaches to systematics have changed dramatically during the last tw. decades w.th the rise of DNA barcoding methods and new.r multi-locus methods for species delimitation. During the last half-decade, partly driven by the new.sequencing technologies, the focus has shifted to multi-locus sequence data and the identification of species w.thin the frame-w.rk of the multi-species coalescent （MSC）. In this paper, I discuss model-based Bayesian methods for species delimitation that have been developed in recent years using the MSC. Several approximate methods for species delimitation （and their limitations） are also discussed. Explicit species delimitation models have the advantage of clarifying more precisely w.at is being delimited and w.at assumptions w. are making in doing so. Moreover, the methods can be very pow.rful w.en applied to large multi-locus datasets and thus take full advantage of data generated using today＇s technologies [Current Zoology 61 （5）： 846-853,2015].

关键词： Bayesian species delimitation Species concepts Multi-species coalescent

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