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Bone Research 2015年第1期3卷 40-45页

作者： douglas j digirolamo Vandana Singhal Xiaoli Chang Se-jin Lee Emily L Germain-Lee Department of Orthopaedic Surgery Johns Hopkins University School of Medicine Bone & Osteogenesis Imperfecta Department Kennedy Krieger Institute Department of Molecular Biology and Genetics Johns Hopkins University School of Medicine Department of Pediatrics Johns Hopkins University School of Medicine

Osteogenesis imperfecta（OI） comprises a group of heritable connective tissue disorders generally defined by recurrent fractures, low bone mass, short stature and skeletal fragility. Beyond the skeletal complications of OI,many patients also report intolerance to physical activity, fatigue and muscle weakness. Indeed, recent studies have demonstrated that skeletal muscle is also negatively affected by OI, both directly and indirectly. Given the well-established interdependence of bone and skeletal muscle in both physiology and pathophysiology and the observations of skeletal muscle pathology in patients with OI, we investigated the therapeutic potential of simultaneous anabolic targeting of both bone and skeletal muscle using a soluble activin receptor 2B（ACVR2B） in a mouse model of type Ⅲ OI（oim）. Treatment of 12-week-old oim mice with ACVR2 B for 4 weeks resulted in significant increases in both bone and muscle that were similar to those observed in healthy,wild-type littermates. This proof of concept study provides encouraging evidence for a holistic approach to treating the deleterious consequences of OI in the musculoskeletal system.

关键词： bone Administration of soluble activin receptor 2B increases bone and muscle mass in a mouse model of osteogenesis imperfecta

Osteoblast-restricted Disruption of the Growth Hormone Receptor in Mice Results in Sexually Dimorphic Skeletal Phenotypes

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Bone Research 2013年第1期1卷 85-97页

作者： Vandana Singhal Brian C.Goh Mary L.Bouxsein Marie-Claude Faugere douglas j.digirolamo Department of Orthopaedic Surgery Johns Hopkins University School of MedicineBaltimoreMDUSA Center for Advanced Orthopedic Studies Beth Israel Deaconess Medical Center and Harvard Medical SchoolBostonMAUSA Albert B.Chandler Medical Center University of KentuckyLexingtonKYUSA

Growth hormone （GH） exerts profound anabolic actions during postnatal skeletal development, in part, through stimulating the production of insulin-like growth factor-1 （IGF-1） in liver and skeletal tissues. To examine the requirement for the GH receptor （GHR） in osteoblast function in bone, we used Cre-LoxP methods to disrupt the GHR from osteoblasts, both in vitro and in vivo. Disruption of GHR from primary calvarial osteoblasts in vitro abolished GH-induced signaling, as assessed by jAK2/STAT5 phosphorylation, and abrogated GH-induced proliferative and anti-apoptotic actions. Osteoblasts lacking GHR exhibited reduced IGF-l-induced Erk and Akt phosphorylation and attenuated IGF-1-induced proliferation and anti-apoptotic action. In addition, differentiation was modestly impaired in osteoblasts lacking GHR, as demonstrated by reduced alkaline phosphatase staining and calcium deposition. In order to determine the requirement for the GHR in bone in vivo, we generated mice lacking the GHR specifically in osteoblasts （△GHR）, which were born at the expected Mendelian frequency, had a normal life span and were of normal size. Three week-old, female AGHR mice had significantly reduced osteoblast numbers, consistent with the in vitro data. By six weeks of age however, female AGHR mice demonstrated a marked increase in osteoblasts, although mineralization was impaired; a phenotype similar to that observed previously in mice lacking IGF-1R specifically in osteoblasts. The most striking phenotype occurred in male mice however, where disruption of the GHR from osteoblasts resulted in a ＂feminization＂ of bone geometry in 16 week-old mice, as observed by faCT. These results demonstrate that the GHR is required for normal postnatal bone development in both sexes. GH appears to serve a primary function in modulating local IGF-1 action. However, the changes in bone geometry observed in male AGHR mice suggest that, in addition to facilitating IGF-1 action, GH may function to a greater

关键词： growth hormone osteoblasts knockout mice bone sexual dimorphism

Free perforation of the small intestine in collagenous sprue

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World journal of Gastroenterology 2009年第35期15卷 4446-4448页

作者： Hugh j Freeman douglas L Webber Departments of Medicine(Gastroenterology) University of British ColumbiaVancouverBC V6T 1W5Canada Departments of Pathology University of British ColumbiaVancouverBC V6T 1W5Canada

A 67-year-old man with celiac disease developed recurrent diarrhea,profound weakness and weight loss, with evidence of marked protein *** clinical course was refractory to a strict gluten-free diet and steroid *** studies led to definition of unrecognized collagenous sprue that caused ulceration and small intestinal *** PCR showed identical monoclonal T-cell populations in antemortem duodenal biopsies and postmortem jejunum,careful pathological evaluation demonstrated no frank ***,overt or even cryptic T-cell lymphoma may complicate collagenous sprue,however, small intestinal ulcers and perforation may also develop *** dramatic findings here may reflect an underlying or early molecular event in the eventual clinical appearance of overt T-cell lymphoma.

关键词： Collagenous sprue Intestinal perforation Celiac disease Refractory sprue Intestinal neoplasms Lymphoma

Potential influence of wildfire in modulating climate-induced forest redistribution in a central Rocky Mountain landscape

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Ecological Processes 2017年第1期6卷 52-68页

作者： john L.Campbell douglas j.Shinneman Department of Forest Ecosystems and Society Oregon State UniversityCorvallisORUSA U.S.Geological Survey Forest and Rangeland Ecosystem Science CenterBoiseIDUSA.

Introduction:Climate change is expected to impose significant tension on the geographic distribution of tree ***,tree species range shifts may be delayed by their long life spans,capacity to withstand long periods of physiological stress,and dispersal *** could theoretically break this biological inertia by killing forest canopies and facilitating species redistribution under changing *** investigated the capacity of wildfire to modulate climate-induced tree redistribution across a montane landscape in the central Rocky Mountains under three climate scenarios(contemporary and two warmer future climates)and three wildfire scenarios(representing historical,suppressed,and future fire regimes).Methods:Distributions of four common tree species were projected over 90 years by pairing a climate niche model with a forest landscape simulation model that simulates species dispersal,establishment,and mortality under alternative disturbance regimes and climate ***:Three species(douglas-fir,lodgepole pine,subalpine fir)declined in abundance over time,due to climate-driven contraction in area suitable for establishment,while one species(ponderosa pine)was unable to exploit climate-driven expansion of area suitable for *** fire frequency accelerated declines in area occupied by douglas-fir,lodgepole pine,and subalpine fir,and it maintained local abundance but not range expansion of ponderosa ***:Wildfire may play a larger role in eliminating these conifer species along trailing edges of their distributions than facilitating establishment along leading edges,in part due to dispersal limitations and interspecific competition,and future populations may increasingly depend on persistence in locations unfavorable for their establishment.

关键词： Forest disturbance Wildfire Climate change Central Rocky Mountains Climate niche Species migration Species distribution

Parallel boron nitride nanoribbons and etch tracks formed through catalytic etching

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Nano Research 2018年第9期11卷 4874-4882页

作者： Armin Ansary Mohsen Nasseri Mathias j. Boland douglas R. Strachan Department of Physics &Astronomy University of Kentucky Lexington KY40506 USA

One-dimensional （1D） catalytic etching was investigated in few-layer hexagonal boron nitride （hBN） films. Etching of hBN was shown to share a number of similarities with that of graphitic films. As in graphitic films, etch tracks in hBN commenced at film edges and occurred predominantly along certain crystal directions of its lattice, though it was shown that the tracks were generally narrower than those of few-layer graphene under similar processing conditions. It was also shown that catalytic hydrogenation can occur completely through a few-layer hBN film, demonstrating that this process can be used in the formation of isolated low-dimensional nanoscale structures from other layered 2D materials beyond graphene. This ability for thin hBN films to be etched completely through allowed for a crystalline substrate to guide the etching process, which was demonstrated with the successful etch track formation of few-layer hBN on single-crystalline sapphire substrates. The substrate-guided etching resulted in parallel few-layer hBN nanoribbons having an average width of 32 nm and spacing of 13 nm.

关键词： hexagonal(hBN) one-dimensional catalytic etching hydrogenation etch tracks nanoribbons

Slab and Level 2 Automation Design Guidelines for Optimum Metallurgy and Productivity for Plate and Steckel Mills

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journal of Iron and Steel Research International 2011年第S1期18卷 550-556页

作者： Stalheim douglas DGS Metallurgical Solutions Inc. 15003 NE 10th StreetVancouverWA 98684 USA

Many new steel plate processing facilities have been built in the past 10 years around the world with many more being planned for the *** is especially true in developing countries such as China,India and *** of these facilities are plate mills with either one or two stands or a Steckel mill,typically only one stand designed for the production of structural plate ***,there is a lack of understanding with both the mill builders of the world and the mill owners on the importance of properly matching up the available slab supply (either new as part of a new plate/Steckel mill complex or part of an already existing) with the desired end plate product *** mill builders and owners around the world believe that you can take any slab of any dimension and make any plate dimension you *** this is basically true with today’s Level 2 automation systems,it does not always result in optimum metallurgy/mechanical properties or *** less than optimum condition results in mechanical property failures,shape issues,productivity losses and in general a less than desirable costly processing *** is important to the overall optimization of a steel processing facility that the proper slab dimensions be used to produce the proper final plate dimensions along with achieving the required mechanical *** critical nature of this selection will be dependent on the final plate thickness and overall mechanical property *** mechanical property,shape and overall microstructure are heavily dependent on the ability to properly work the entire cross section of the slab through the rolling *** mechanical property,shape and microstructural issues are a result of improper working of the entire cross section during *** ability for a given mill to properly work the entire cross section is dependent on proper slab selection (total reduction ratio) and a proper rolling schedule either generated manual

关键词： slab dimensions optimization grain size rolling schedule automation Level 2

Metallurgical Optimization of Microalloyed Steels for Oil and Gas Transmission Pipelines

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journal of Iron and Steel Research International 2011年第S1期18卷 669-674页

作者： Stalheim douglas DGS Metallurgical Solutions Inc. 15003 NE 10th StreetVancouverWA98684 USA

The production of microalloyed steels for oil and gas transmission pipelines has increased significantly over the past *** more and more countries developing their own capabilities to produce pipeline steels to support their own internal pipeline infrastructure development,there has been an increase of steel producers working to develop their own capabilities to produce microalloyed steels for this ***,to achieve the desired mechanical property attributes for transmission pipeline applications utilizing a cost effective approach requires metallurgical optimization of the microalloyed *** achieve metallurgical optimization a basic understanding is required in the design of a cost effective alloy and then the proper processing of that alloy design to achieve the optimum microstructure/mechanical *** this sense,many producers in the world,especially those who have only recently,in the past 10 years,developed their capability to produce microalloyed transmission pipeline steels still do not achieve metallurgical optimization of their alloy and *** results in yield losses due to failures,inefficient processing causing productivity losses and additional expensive additions of alloys to compensate for failures and process *** the supplier of plate/coil has the largest percentage effect on the final cost of the pipe,the steel producer must understand proper alloy,microstructure,and process design to produce a uniform and stable plate/coil to be used in pipe *** means that strength,toughness and microstructure must be uniform down the length,across the width and through the cross *** optimization is achieved when this uniformity is achieved with a cost effective *** to that,non-uniformity results in pipe forming,welding,expansion,mechanical property and production issues resulting in downgraded pipe and cost overruns in *** paper will describe targets for p

关键词： microalloy niobium pipeline solubility grain size rolling schedule

Simulated Microbe Removal around Finger Rings Using Different Hand Sanitation Methods

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International journal of Oral Science 2009年第3期1卷 136-142页

作者： Archana A. Alur Madhavi j. Rane james P. Scheetz douglas j. Lorenz Lawrence Gettleman Ballard High School Louisville Kentucky USA School of Medicine University of Louisville Louisville Kentucky USA School of Dentistry University of Louisville Louisville Kentucky USA School of Public Health & Information Sciences University of Louisville Louisville Kentucky USA

Aim It is our opinion that the CDC and the WHO have underestimated cross-contamination under examination gloves in dental clinics while wearing jewelry, such as finger rings. These agencies only ＂recommend＂ removing jewelry, and only washing hands for 15 seconds with soap and warm water before donning gloves. This study examined several washing procedures and finger rings using simulated microbes. Methodology A gloved robber hand manikin was made and fitted with a flesh disposable vinyl glove. Four fingers were fitted with rings or no ring, dusted with simulated microbes, and washed with a scrub brush for 5, 15, and 25 seconds under 20℃ and 40℃ water alone, or with liquid hand soap. Light levels （in lux） of fluorescent powder before and after washing were measured and delta scores calculated for changes in light levels, equivalent to effectiveness of hand washing procedures. A full-factorial, 3-factor analysis of variance （ANOVA） was used to test for differences among levels of the three study factors-time, temperature, and soap use. Tukey＇s post hoc honestly significant difference （HSD） test was applied to significant factors to examine pair-wise differences between factor levels. Results It was found that the longer the hands with rings were washed with a scrub brush under flowing water, the more simulated microbes were removed. By 25 seconds, all methods were essentially the same. Simulated microbes were more difficult to remove from the palm compared to the back of the hand. The liquid hand soap used in this study was more effective with warm water than cold. When given a choice of washing with cold water up to 15 seconds, it would be preferable not to use soap to remove simulated microbes. Qualitatively, the outer surface of finger rings were more effectively cleaned than the crevice below the ring, and the ring with a stone setting appeared to accumulate and retain simulated microbes more than other rings. Conclusion The most effective treatment was washing wi

关键词： dental exam gloves finger ring jewelry crosscontamination hand hygiene microbes fluorescent powder dental health care workers

Texture-based latent space disentanglement for enhancement of a training dataset for ANN-based classification of fruit and vegetables

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Information Processing in Agriculture 2023年第1期10卷 85-105页

作者： Khurram Hameed douglas Chai Alexander Rassau School of Engineering Edith Cowan University270 Joondalup DriveJoondalup WA 6027PerthAustralia

The capability of Convolutional Neural Networks(CNNs)for sparse representation has significant application to complex tasks like Representation Learning(RL).However,labelled datasets of sufficient size for learning this representation are not easily *** unsupervised learning capability of Variational Autoencoders(VAEs)and Generative Adversarial Networks(GANs)provide a promising solution to this issue through their capacity to learn representations for novel data samples and classification *** this research,a texture-based latent space disentanglement technique is proposed to enhance learning of representations for novel data samples.A comparison is performed among different VAEs and GANs with the proposed approach for synthesis of new data *** different VAE architectures are considered,a single layer dense VAE and a convolution based VAE,to compare the effectiveness of different architectures for learning of the *** GANs are selected based on the distance metric for disjoint distribution divergence estimation of complex representation learning *** proposed texture-based disentanglement has been shown to provide a significant improvement for disentangling the process of representation learning by conditioning the random noise and synthesising texture rich images of fruit and vegetables。

关键词： Information Maximisation(IM) Fruit and vegetables classification Representation Learning(RL) Variational Autoencoder(VAE) Generative Adversarial Network (GAN) Latent space disentanglement

Operator Splitting for Three-Phase Flow in Heterogeneous Porous Media

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Communications in Computational Physics 2009年第6期6卷 72-84页

作者： E.Abreu j.douglas F.Furtado F.Pereira Instituto Nacional de Matematica Pura e Aplicada RJ 22460-320Brazil Department of Mathematics Purdue UniversityWest LafayetteIN 47907-1395USA Department of Mathematics University of WyomingLaramieWY 82071-3036USA Department of Mathematics and School of Energy Resources University of WyomingLaramieWY 82071-3036USA

We describe an operator splitting technique based on physics rather than on dimension for the numerical solution of a nonlinear system of partial differential equations which models three-phase flow through heterogeneous porous *** model for three-phase flow considered in this work takes into account capillary forces,general relations for the relative permeability functions and variable porosity and permeability *** our numerical procedure a high resolution,nonoscillatory,second order,conservative central difference scheme is used for the approximation of the nonlinear system of hyperbolic conservation laws modeling the convective transport of the fluid *** scheme is combined with locally conservative mixed finite elements for the numerical solution of the parabolic and elliptic problems associated with the diffusive transport of fluid phases and the pressure-velocity *** numerical procedure has been used to investigate the existence and stability of nonclassical shock waves(called transitional or undercompressive shock waves)in two-dimensional heterogeneous flows,thereby extending previous results for one-dimensional flow *** experiments indicate that the operator splitting technique discussed here leads to computational efficiency and accurate numerical results.

关键词： Operator splitting three-phase flow heterogeneous porous media central differencing schemes mixed finite elements