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We use frequency-dependent connectedness measures to study the role played by the telecommunications (telecoms) sector in sectoral default risk connectedness at three frequency bands, i.e. the shor...

Acute diarrhoea continues to be a leading cause of morbidity, hospitalisation, and mortality worldwide, and probiotics have been proposed as a complementary therapy in the treatment of acute diarrhoea. The goal of this study is to assess the efficacy and safety of three combined probiotic strains, Bifidobacterium lactis Bi-07, Lactobacillus rhamnosus HN001, and Lactobacillus acidophilus NCFM, as an adjunct to rehydration therapy in treatment of acute watery diarrhoea in hospitalised children. Eligible diarrheal children were randomised into intervention group (IG, n=96, conventional treatment for diarrhoea in combination with probiotics) and control group (CG, n=98, conventional treatment for diarrhoea without probiotics). The primary assessments of this study were duration of diarrhoea and hospital stay and improvement in diarrhoea symptoms. Significantly more children in the IG showed improvements in diarrhoea (defined as a decrease of stool frequency to no more than four times per day and an improved stool consistency within 24-48 h after the treatment) than those in the CG (96.9 vs 79.6%, P

We describe a unique ABO compatible and 9/10 HLA-matched case of successful allogeneic hematopoietic cell transplantation (HCT) after effective desensitization of a strong anti-HLA-A24 donor-specific antibody (DSA) with mean fluorescence intensity of approximately 18 000. Due to absence of a suitable matched unrelated donor the patient sibling was considered the best available donor, and it was decided to desensitize patient prior to transplant. The strength of HLA-A24 DSA slowly decreased over the course of treatment, necessitating a total of 23 sessions of therapeutic plasma exchange in order to bring the DSA strength to undetectable levels, followed by a successful transplant. In summary, the outcome of this case shows effective application of desensitization treatment to remove strong DSA in HCT patients.

Lithium niobate (LN), an outstanding and versatile material, has influenced our daily life for decades: from enabling high-speed optical communications that form the backbone of the Internet to realizing radio-frequency filtering used in our cell phones. This half-century-old material is currently embracing a revolution in thin-film LN integrated photonics. The success of manufacturing wafer-scale, high-quality, thin films of LN on insulator (LNOI), accompanied with breakthroughs in nanofabrication techniques, have made high-performance integrated nanophotonic components possible. With rapid development in the past few years, some of these thin-film LN devices, such as optical modulators and nonlinear wavelength converters, have already outperformed their legacy counterparts realized in bulk LN crystals. Furthermore, the nanophotonic integration enabled ultra-low-loss resonators in LN, which unlocked many novel applications such as optical frequency combs and quantum transducers. In this Review, we cover -- from basic principles to the state of the art -- the diverse aspects of integrated thin-film LN photonics, including the materials, basic passive components, and various active devices based on electro-optics, all-optical nonlinearities, and acousto-optics. We also identify challenges that this platform is currently facing and point out future opportunities. The field of integrated LNOI photonics is advancing rapidly and poised to make critical impacts on a broad range of applications in communication, signal processing, and quantum information., Review article. 94 pages, 44 figures, 497 references

To solve the problem of robot visual servoing on unknown object, we apply deep learning to the robotics control and propose a manipulator visual positioning method based on deep learning. Firstly, we use a well-trained object detection network based on deep learning to recognize and detect objects in the first frame image, which is captured by the camera mounted on the robot; Then, user randomly selects object to be manipulated through human-computer interaction according to the result of recognition and detection. In the sequence of subsequent images, robotics control system can detect the object to be manipulated using this object class label information and well-trained object detection network; Finally, we can calculate the features error and design the visual sliding mode controller to control the manipulator to position the unknown object randomly selected by the user in the first frame image. We conduct two robotics experiments of visual positioning on unknown object in the complex nature scenes using a MOTOMAN-SV3X industrial manipulator. Experimental results show that our manipulator visual positioning method can position an unknown object without having to known any model information about the object prior to the positioning task execution, and it is an effective manipulator visual positioning on unknown object method.

Objective Chimney endovascular aneurysm repair (Ch-EVAR) is a cheap and immediately available method for treatment of juxtarenal aortic aneurysms (JRAAs). The aim of this study was to report experiences and results with balloon expandable stent (BES) for Ch-EVAR. Methods From January 2008 to June 2013 (mean time, 26 ± 13 months), 42 patients who underwent Ch-EVAR were retrospectively reviewed. All patients were thought to be at high risk for open surgery and were unsuitable (because of financial issues and fear of delays) for fenestrated endovascular aneurysm repair (FEVAR). Results 42 patients (35 males; mean age 71 ± 7 years) underwent chimney procedures for 56 renal arteries with 70 BESs (59 hippocampus and 11 genesis). Median follow up was 26 months (range 6–64 months). Primary technical success was 100%. Thirty day mortality was 0%. Completion angiography showed that eight cases (19%) had a type I endoleak. The 6 month follow up CT scans demonstrated three cases with complete regression of endoleak, two cases without aneurysmal growth, and three cases with an increase in aneurysmal diameter of less than 10 mm. Three patients had contrast induced nephropathy (CIN) after Ch-EVAR, two of whom had acute renal failure (ARF) and continue to require hemodialysis. Two deaths occurred during follow up, both unrelated to the aorta: one with a hemispheric stroke at 6 months and one with respiratory failure at 12 months. Therefore, the overall follow up mortality was 5%. Occlusion of one chimney stent occurred 3 months after the procedure, meaning renal artery patency rate was 98%. The aneurysm diameter reduced from 74 ± 9 mm to 64 ± 10 mm during follow up ( p Conclusion Ch-EVAR can be used to treat JRAAs with suitable anatomical conditions. However, complications of type I endoleak were not uncommon, and, therefore, further studies are required to prove its efficiency for JRAAs.

Tubular structures play an important role in energy absorbing components and structural members requiring high strength-to-weight ratio. The theory of buckling of circular, square and rectangular tubes is relatively well established in the literature. The study of buckling of triangular tubes, however, has received much less attention. In this paper, an analytical solution for the elastic buckling of isosceles triangular tubes was obtained by considering the buckling characteristics of individual walls of the triangular tube with appropriate edge conditions. The results from this analytical solution were compared with previously published work in the literature and finite element simulations. The comparison revealed good agreement between these results.

Hypertrophic cardiomyopathy (HCM) is often transmitted to the offspring of affected individuals. This case report describes the role of genetic screening in a 39-year-old woman with a family history of sudden cardiac death. The patient wished to become pregnant and was seeking medical consultation. In addition to electro- and echocardiograms, genomic DNA was isolated and direct sequencing was employed to screen the patient for some of the most common genes that cause HCM. A pathogenic heterozygous mutation c.700 g > a p.Arg186Gln in TNNI3 was identified, which was not found in 200 normal control chromosomes. Mutation-specific genetic testing was also performed in four family members, and the same mutation was absent. Genetic screening appears cost effective in familiar members with a known mutation, provides important information about the affected individual, and can facilitate the future management of family members and offspring.

Bananas (Musa spp.) are subject to a number of diseases that are difficult to diagnose early in development when control measures are most likely to be successful. Rapidly spreading new diseases, such as Xanthomonas wilt present unique diagnostic challenges. Surveys conducted in East and West Africa documented the lack of sufficient equipment, supplies, reference materials and training in the majority of plant pathology laboratories charged with disease diagnoses. To begin to address these issues, the International Plant Diagnostic Network (IPDN) was established in East and West Africa in 2006, through the Integrated Pest Management Collaborative Research Support Program (IPM CRSP). The IPDN is a diagnostic, communication and data network, modeled in part on the United States National Plant Diagnostic Network. Software for digital imaging and diagnosis and information management provides a platform for enhanced diagnosis and communication amongst clinicians and their clientele. Improved diagnostics tools and protocols were also developed and tested, including a PCR assay for Xanthomonas wilt. Training programs were conducted in Benin in 2006, Kenya and the United States of America in 2007, and Uganda and Mali in 2008, to enhance technical capacity amongst diagnosticians in East and West Africa. Initiatives such as IPDN can benefit by collaboration with other similar internet-based initiatives in Africa. One such activity is the East Africa Phytosanitary Information Committee (EAPIC). EAPIC is linked to the Food and Agricultural Organization's International Plant Portal to provide the official national plant protection organization posting of plant pests for each respective country, which now includes Kenya, Tanzania, Uganda and Zambia. The plant pest list will serve as a foundation from which to develop harmonized border inspection protocols, which in turn support capacity building efforts in plant pest survey, identification and communication systems, such as IPDN.

A female patient presented for follow-up care approximately ten years post-cardiac transplantation. HLA antibody testing revealed multiple class I and class II donor specific antibodies (DSA), including anti-HLA A1 (MFI > 2500), DQ6, and DQ7/DQ8/DQ9 antibodies (DQ antibodies have MFIs >15,000). Per our current testing protocols, the sample was reflexed to C1q to determine if any DSAs were complement- fixing. As expected, based on antibody strength, the class II DSAs were C1q positive, while anti-HLA A1 was C1q negative. Interestingly, C1q testing revealed reactivity for anti-HLA B8 which was not previously detected by our standard IgG testing methodology. While anti-HLA B8 was not a DSA to the previous transplant, we wanted to determine the underlying cause for the positive reactivity seen with C1q testing: prozone effect or IgM? Since our laboratory routinely treats all sera tested for HLA antibodies with EDTA prior to testing, we thought prozone was unlikely as previous studies performed in our lab demonstrated the removal of this effect. Nonetheless, to rule out prozone with another method, IgG testing was repeated using a series of dilutions (Neat, 1:4, 1:16, 1:64, and 1:256). This testing did not yield positive reactivity for anti-HLA B8, and therefore prozone effect was excluded, indicating that EDTA methodology is robust to overcome prozone effect. To confirm the isotype of this antibody, IgM testing was conducted in three sera using the same assays as the IgG testing which produced positive results. In conclusion, anti-HLA B8 was determined to be complement-fixing and of the IgM isotype. Unexpectedly, our results supported the absence of an IgM-IgG isotype class switch for the period of testing performed in our lab spanning 17 months. *RLU and JJX contributed equally to this work.

Background Endovascular repair by stent graft has been developed as a safe and less-invasive treatment for descending thoracic and abdominal aortic diseases. In case of involvement of the aortic arch, the challenge in endovascular repair is to maintain blood flow to the brain and upper extremities. Several studies have been done trying to repair this difficult part of the aorta with different stent grafts, and we have developed a new stent-graft device for aortic arch reconstitution. We implanted the new device in canine models to test its feasibility. Methods and results The new stent graft was composed of three components: parts I and II were both bifurcated, one with long, narrow limb and the other short and wide, and part III was a tubular component. Ten adult hybrid dogs were operated with the new stent-graft procedure, and eight were successfully implanted with the stent grafts. The technical success rate was 80% (8 of 10). Five dogs survived for 3 months without obvious cerebral, visceral or limb ischaemia. Autopsies showed that the implanted stent grafts were patent and the vital side branches of aortic arch were well preserved. Conclusions Our study demonstrates that it is possible to reconstruct aortic arch with the new branched stent grafts. The advantage of this device is that it is modular, more adaptable and surgical bypass could be possibly avoided.

Background Glucocorticoid resistance has been associated with Th17-driven inflammation, the mechanisms of which are not clear. We determined whether human and mouse Th17 cells are resistant to glucocorticoid-induced apoptosis. Methods Freshly isolated human blood Th17 cells and in vitro differentiated Th17 cells from IL-17F red fluorescent protein reporter mice were treated with dexamethasone, a potent glucocorticoid. Apoptosis was measured using annexin V and DAPI staining. Screening of apoptosis genes was performed using the apoptosis PCR array. Levels of molecules involved in apoptosis were measured using quantitative RT-PCR, flow cytometry, and Western blotting. Knockdown of BCL-2 in murine Th17 cells was performed via retroviral transduction. Cytokines were measured using ELISA. A murine Th17-driven severe asthma model was examined for Th17 glucocorticoid sensitivity in vivo. Results Human and mouse Th17 cells and mouse Th2 cells were resistant to glucocorticoid-induced apoptosis. Th17 cells had glucocorticoid receptors levels comparable to those in other T effectors cells. Th17 cells had high levels of BCL-2, knockdown of which sensitized Th17 cells to dexamethasone-induced apoptosis. Production of IL-22, but not IL-17A and IL-17F, was suppressed by glucocorticoids. STAT3 phosphorylation in Th17 cells was insensitive to glucocorticoid inhibition. Lung Th17 cells in the murine severe asthma model were enhanced, rather than suppressed, by glucocorticoids. Conclusion Th17 cells are resistant to glucocorticoid-induced apoptosis and cytokine suppression, at least in part due to high levels of BCL-2. These findings support a role of Th17 cells in glucocorticoid-resistant inflammatory conditions such as certain endotypes of asthma.

The paper discusses a model to estimate the diffraction loss in stacked quantum well slabs for optically pumped lasers. Two quantum well slabs, cleaved from the same strip, are stacked together with the front sides facing each other to form the laser cavity. Misalignment and different slab sizes are possible, which may result in additional diffraction loss. The model is based on the diffraction integral theory to calculate the fundamental mode in a plane mirror resonator. Model results suggest that, for a small misalignment size of a few percent of the wavelength, the diffraction loss is relatively small compared with other sources of loss in the laser system. Hence, the stacked scheme is feasible for the long wavelength far-infrared region but not suitable for shorter wavelengths in the mid- or near-infrared regions. This model is in general applicable to other optically pumped quantum well lasers.

OBJECTIVE To explore the role of contrast-enhanced ultrasound (CEUS) in the early evaluation of microvacularization in patients with aggressive B-cell lymphoma treated by R-CHOP. MATERIALS AND METHODS Fifty-two patients with aggressive B-cell lymphoma underwent combined rituximab-CHOP treatment (CHOP: cyclophosphamide, hydroxydaunomycin, vincristine, prednisonetreatment). Before the treatment and after the first two cycles of R-CHOP, CEUS was performed to assess the microvascularization of tumors. In addition, PET/CT examination was also included in this study before and after the treatment. Ideal cut-off value of CEUS parameters was calculated using receiver-operating characteristic (ROC) curve analysis to predict the treatment outcome. The response to treatment, progression-free survival (PFS) and overall survival (OS) were then compared according to PET/CT and CEUS results. The correlation between CEUS parameters and PET/CT results was investigated based on these analyses. RESULTS All patients were non-Hodgkin lymphomas (NHL) with CD20 positive. The variations of CEUS parameters (peak intensity and mean intensity) at the mid-term of R-CHOP treatment significantly associated with results of treatment response (P < 0.001), and were also positive correlation with PET/CT results (P = 0.001). The CEUS positive or negative results were determined by cut-off points of peak intensity and mean intensity (4.70 and 4.15dB). The median time of clinical follow-up was 35.4 months. Kaplan-Meier survival analysis demonstrated that PET/CT and CEUS were both good predictors for PFS and OS rate in these patients.

A 71 year old female was initially diagnosed with myelodysplastic syndrome (del 5q) which progressed to AML one year later. Patient had pancytopenia, experienced bruising, and needed blood transfusions. Allogeneic stem cell transplant was recommended and she presented to the University of Chicago Medicine for allo-stem cell transplant work up. This patient had one potential related donor (sibling), who was a 9/10 match (mismatch at HLA-A). When examining the patient’s HLA antibodies, it was found that she was highly sensitized, and anti-HLA-A24 was a donor specific antibody (DSA). A search for matched unrelated donors was conducted but no suitable donors were found. It was decided to accept her sibling and desensitize the patient prior to transplant. The desensitization protocol consisted of plasmapheresis (PP), with IVIG (100 mg/kg) given after each PP. The initial MFI of the DSA was >18,000 and showed evidence of rebound after each PP. As a result, PP was performed daily or every other day, with A24 MFI measurement before and after each PP (Figure). While the strength of A24 decreased over the course, a total of 18 sessions of PP were needed to decrease the strength to Download : Download high-res image (161KB) Download : Download full-size image

Aim Autoimmunity introduces a variety of difficulties in interpretation of solid phase HLA antibody testing due to autoantibodies present in patient serum. However, because autoantibodies may be present without obvious symptoms or a clear diagnosis, this information is always available when interpreting HLA test results. The current study sought to establish a mechanism for detecting these patients and generate an algorithm for handling samples with autoantibodies. Methods We retrospectively searched the electronic medical record to identify patients with autoimmune disease who were tested by our lab for HLA alloantibodies, and further cataloged any issues encountered during testing of these patients’ samples. This information was subsequently used to formulate an algorithm for testing autoimmune samples. Results A total of 214 patients with diagnosed autoimmunity were identified, including patients with organ-specific autoimmune conditions, most commonly type 1 diabetes mellitus (n = 43, 20%), and systemic autoimmune conditions, most commonly systemic lupus erythematosus (n = 29, 13.6%) and Sarcoidosis (n = 6, 2.8%). The most common issues encountered during testing were found to be high background on solid-phase antibody testing (n = 38, 17.8%), difficulties in assigning Ab specificities (n = 10, 4.7%), many allele specific antibody assignments (n = 5, 2.3%); and antibodies against self HLA antigens (n = 1, 0.5%). A workflow was designed to detect these patients and handle their samples (Fig. 1). Conclusions Using patients with diagnosed autoimmunity, we identified a high rate of interference of autoantibodies with solid phase HLA antibody assays. Extrapolating these results to a testing algorithm, we hope to be able to more readily detect and document patient samples that require special handling for autoantibody interference, even in the absence of an official autoimmunity diagnosis. Download : Download high-res image (170KB) Download : Download full-size image

Models were developed to describe the vaporization of well-mixed wall films of multi-component engine fuels based on continuous thermodynamics and applied to describing multi-component fuel spray-wall interactions. All the models were implemented into the KIVA3V Release 2.0 code. Validation calculations were conducted for pulsed injection cases and compared with experimental wall film thickness data under different air-fuel ratios and inflow conditions in an inclined pipe, which simulates an intake port of port fuel injection engines. Calculations with single-component iso-octane fuel were also conducted for comparison. The influence of wall temperature, inflow-air velocity and injection angle on the gasoline wall film characteristics was studied. The results indicate that the multi-component fuel film is composed of increasingly heavy species as the vaporization proceeds. The fuel-film structure which results from spray-pipe-wall interaction is greatly different from that resulting from spray-plane-wall interaction. An increase in the wall temperature significantly decreases both the film thickness and the film area. The injection angle significantly changes the wall film structure. Although the inflow velocity enhances the fuel vaporization rate, it has a relatively small effect on the fuel film movement along the pipe wall.

The rock bream fish Oplegnathus fasciatus is one of the most popular aquaculture species in China. In the present study, 15 novel polymorphic microsatellite loci were isolated and characterized from a wild population of O. fasciatus from the Zhoushan coast of China. The number of alleles per polymorphic locus ranged from 4 to 9 in a sample of 30 individuals. Observed and expected heterozygosities per locus varied from 0.267 to 0.767 and from 0.395 to 0.859, respectively. Eleven of the 15 microsatellite loci conformed to Hardy-Weinberg equilibrium. No significant linkage disequilibrium between pairs of loci was detected. The present microsatellite markers could provide a useful tool for the genetic analyses of O. fasciatus.

Numerical simulations of direct injection (DI) heavy-duty diesel engine combustion over the entire engine operating range were conducted using the KIVA code, with modifications to the spray, combustion, turbulence, and heat transfer models. In this work, the effect of the rates of species conversion from reactants to products in the combustion model was investigated, and a characteristic-time combustion model was formulated to allow consideration of multiple characteristic time scales for the major chemical species. In addition, the effect of engine operating conditions on the model formulation was assessed, and correlations were introduced into the combustion model to account for the effects of residual gas and Exhaust Gas Recirculation (EGR). The predictions were compared with extensive engine test data. The calculation results had good overall agreement with the experimental cylinder pressure and heat release results, and the multiple-time-scale combustion model is shown to give improved emissions predictions compared to a previous single-time-scale model. Overall, the NO{sub x} predictions are in good agreement with the experiments. The soot predictions are also in reasonable agreement with the measured particulates at medium and high loads. However, at light loads, the agreement deteriorates, possibly due to the neglect of the contribution of SOF in themore » soot model predictions.« less

Fabric systems with through-the-thickness reinforcement have better ballistic strength than those without it. The focus of the current project is to develop the computational capability to evaluate multilayer fabric systems with through-the thickness reinforcement as well as its failure mechanism after ballistic impact. In this project, a numerical model has been established to generate the micro-geometry of fabrics fabricated using TexTech needle-punching technology. A hybrid mesh model has been developed which produces results close to those obtained using full field uniform mesh and yet uses less computer resource by a factor of ten or more. Furthermore, a post-processor has been developed which can display the ballistic perforation process step by step and enables the analysis of the fabric failure mechanism. Based on the work accomplished, we have established the capacity to (1) simulate the fabrication procedure of needle-punching the through-the-thickness fibers into multi-layer fabric systems, (2) conduct ballistic simulations of the TexTech fabric systems with various layer configurations, (3) compare numerical ballistic simulation results to experimental results, and (4) provide information for optimal hybrid design of multilayer fabric systems with through-the-thickness reinforcement.

Methods An inflammatory pain rat model, produced by a complete Freund adjuvant (CFA) injection into the hind paw of each rat, was combined with a conditioned place avoidance (CPA) test. On day one, time spent by the rats in each of two distinct compartments during a 10min period was recorded. On day two, each rat explored one of the conditioning compartments for 30 min. Two hours after the CFA injection, each rat was allowed to explore the second compartment for 30 min. On day three, the time spent by the rats in each compartment was recorded again.

Background Although acupuncture analgesia is well documented, its mechanisms have not been thoroughly clarified. We previously showed that electroacupuncture (EA) activates supraspinal serotonin- and norepinephrine-containing neurones that project to the spinal cord. This study investigates the involvement of spinal alpha(2)-adrenoceptors (α2-ARs) and 5-hydroxytryptamine (serotonin) receptors (5-HTRs) in EA effects on an inflammatory pain rat model. Methods Inflammatory hyperalgesia was induced by injecting complete Freund's adjuvant (CFA, 0.08 ml) into the plantar surface of one hind paw and assessed by paw withdrawal latency (PWL) to a noxious thermal stimulus. The selective α2a-AR antagonist BRL-44408, α2b-AR antagonist imiloxan hydrochloride, 5-HT2B receptor (5-HT2BR) antagonist SB204741, 5-HT3R antagonist LY278584, or 5-HT1AR antagonists NAN-190 hydrobromide, or WAY-100635 were intrathecally administered 20 min before EA or sham EA, which was given 2 h post-CFA at acupoint GB30. Results EA significantly increased PWL compared with sham [7.20 (0.46) vs 5.20 (0.43) s]. Pretreatment with α2a-AR [5.35 (0.45) s] or 5-HT1AR [5.22 (0.38) s] antagonists blocked EA-produced anti-hyperalgesia; α2b-AR, 5-HT2BR, and 5-HT3R antagonist pretreatment did not. Sham plus these antagonists did not significantly change PWL compared with sham plus vehicle, indicating that the antagonists had little effect on PWL. Immunohistochemical staining demonstrated that α2a-ARs are on primary afferents and 5-HT1ARs are localized in N-methyl-d-aspartic acid (NMDA) subunit NR1-containing neurones in the spinal dorsal horn. Conclusions The data show that α2a-ARs and 5-HT1ARs are involved in the EA inhibition of inflammatory pain and that the NMDA receptors are involved in EA action.

Microstructurally sensitive fatigue short crack growth can occur in many engineering components devoid of large defects. Continuum mechanics principles, including linear elastic fracture mechanics, used in damage tolerance design and life prediction methods are not applicable in these situations and therefore new concepts need to be developed to characterize this type of growth. A microstructurally sensitive model of fatigue crack growth is presented in which the effect of microstructure is dominant in the early stage of growth but plays a negligible role after the crack has gone through the transition from structure-sensitive to structure-insensitive growth. The effect of both microstructure and structure sensitive variables on the transition from short cracks to continuum mechanics and the conditions for crack instability leading to final failure are examined. The microstructural variables incorporated in the equations that describe the model are those controlling the extent and intensity of crack tip plasticity such as grain size, precipitation and dispersion hardening, strain hardening and misorientation between grains. It is expected that the concepts developed within the model will form the basis for the design of new crack-resistant materials.

— A theoretical study of the conditions for coalescence of two fatigue cracks in a multi-crack system is presented. As both cracks grow, the near-side plastic zone sizes of the interacting cracks increase more rapidly than the off-side zone sizes which results in higher overall crack propagation rates for an interacting crack growth system than the simple addition of individual crack growth rates. The use of a single crack growth model to predict failure in the presence of two or more cracks may therefore underestimate the interaction between cracks and lead to un-conservative predictions. Some of the theoretical predictions were confirmed by published results of experimental measurements of crack interaction distances in multi-crack systems.

Buckling of plates and tubes plays an important role in structural safety and energy absorption. Although buckling of plates and tubes has been studied theoretically and experimentally in the past, the effects of aspect ratio and side constraint on buckling of multi-wall structures and tubes has not been investigated systematically. In this work, finite element simulations have been carried out to investigate the buckling behavior of multi-wall structures and tubes. A series of one- to three-panel walls and square tubes with various aspect ratios were simulated. The critical aspect ratios causing buckling mode transition were obtained and compared with theoretical predictions available in the literature. Effects of wall angle and side constraint on buckling behavior were investigated. The relevance of research findings to honeycomb-like structures was discussed.Copyright © 2011 by ASME

— Plane strain, elastic-plastic, finite element analyses have been undertaken to simulate stable crack growth in an A508 forging steel for three different sizes of compact tension specimen and for small scale yielding by enforcing the same experimentally-measured deformation theory J resistance curve. The results show that path-dependence of the numerically calculated J-integral occurs from the very beginning of crack growth, and the degree of path-dependence is not strongly related to the amount of crack growth expressed as a proportion of the uncracked ligament. Crack tip stresses and strains are only mildly sensitive to changes in specimen size for the range of crack extension investigated. Small specimens appear to produce more intense deformation than small scale yielding and therefore cause more damage. For a tough steel such as A508 the parameter bσf/Jd, appears to be the most important in limiting the validity of J-characterized fields of deformation ahead of the growing crack.

An analytical procedure is presented for the time‐dependent analysis of a partially prestressed concrete cross section subjected to an increasing load history, The load history is such that cracking of the cross section occurs under a moment increment that is applied after a period of sustained bending. The age‐adjusted effective modulus method is used to include the time‐dependent effects of creep and shrinkage in the concrete both before and after cracking. The analysis is divided into several stages and attention is focussed on the solution of the nonlinear problem created by cracking at some time after first loading. Solution of the nonlinear equations to find the depth of cracking on the cross section and the stresses and strains in both the concrete and the steel is achieved using an iterative Newton‐Raphson procedure. The effect of cracking on the stress and strain distributions determined prior to cracking are examined and the inherent difficulties associated with the ageing of concrete are treate...

This contributions describes the successful implementation of a novel method for in-line continuous deposition of a-Si:H p-i-n solar cells by Hot Wire Chemical Vapour Deposition (HWCVD). As HWCVD does not use RF power supplies, there are no high frequency electromagnetic fields, and thus, scaling up is not hampered by finite wavelength effects or rigorous requirements to avoid inhomogeneous electrical fields. The hot catalytic wire in HWCVD is a linear source of radicals mounted perpendicular to the transport direction. We demonstrate the homogeneous in-line deposition of HWCVD solar cells on upward-facing substrates. The downward, dust-free deposition of thin film silicon greatly simplifies the mounting of the substrates, which can either be rigid or a flexible web, for in-line manufacturing at reduced cost. Amorphous (protocrystalline) as well as nanocrystalline silicon thin films with device-quality properties have been achieved on moving substrates. The local deposition rate is relatively high, at 1 nm/s, and a linear speed up to 30 cm/min has been used to produce device-quality i-layers with protocrystalline nature. We have recently further improved our thus deposited p-i-n solar cells to 8.3% efficiency (despite air breaks after the p-layer and before the n-layer). The potential for high deposition rate and fast roll-to-roll deposition is also discussed.

A module-based approach is promoted for introducing FEM applications into undergraduate engineering courses. A Learning Module (LM) is defined as a well-structured, compact, and self-sufficient learning resource that provides a learner the desired contents in a precise and concise manner, enabling the learner to learn efficiently and effectively. Each LM is designed to be equivalent to one week’s learning time. A navigatable and editable multi-media (NEMM) format of presentation for learning modules is proposed. Critical to the construction of a learning module is the principle of conceptual analysis which allows the extraction of general concepts, principles, and procedures from FEM software specifics. Two learning modules are developed, and their efficacy in FEM learning is assessed. The pedagogical foundations behind the module-based learning are explored from the cognitive science perspective. The advantages and disadvantages of the module-based learning are discussed.Copyright © 2010 by ASME

The finite element method (FEM) has become an indispensable tool for design, analysis, and modeling in a vast array of engineering and applied science disciplines. Despite its importance, however, FEM is typically not a required undergraduate course. In this work, a module-based approach is promoted for introducing FEM applications into undergraduate engineering courses without the need for a major revision of the course content or the existing curricula. A Learning Module (LM) is defined as a well-structured, compact, and self-sufficient learning resource that provides a learner the required content in a precise and concise manner, enabling the learner to learn efficiently and effectively. The organization and essential components of an FEM learning module are discussed in detail. Critical to the construction of a learning module is the principle of conceptual analysis which allows the extraction of general concepts, principles, and procedures from FEM software dependent specifics. The application of conceptual analysis throughout the development of learning modules is demonstrated and discussed. The pedagogical foundations behind the module-based learning are explored from the cognitive science perspective, and implications of module-based learning in undergraduate education are discussed.Copyright © 2009 by ASME

Background and Study Aims: Intraoperative interstitial brachytherapy has been found to be effective when used during laparotomy to improve local control in patients with locally advanced pancreatic cancer. In this study, we report the results of using endoscopic ultrasound- (EUS-)guided interstitial brachytherapy in patients with advanced pancreatic cancer, with respect to tumor response, clinical response, safety, and complications.Patients and Methods: Fifteen patients (eight men, seven women; median age 61 years) with unresectable pancreatic adenocarcinoma were enrolled into the study, eight patients with stage III disease and seven patients with stage IV disease. A mean number of 22 radioactive seeds per patient were implanted into the tumors by EUS-guided needle puncture. The mean total implanted activity was 20 mCi, the minimum peripheral dose was 14 000 cGy, and the mean volume of implants was 52 cm3. Patients were followed-up by examination and by imaging tests every 2 - 3 months: clinical end points included the Karnofsky performance status and pain responses, tumor response (assessed by computed tomography and/or EUS), and survival.Results: During a median follow-up period of 10.6 months, the objective tumor response was classified as “partial” in 27 % of patients (with a median duration of partial response of 4.5 months), ”minimal” in 20 % patients, and indicative of “stable disease” in 33 % of patients. Clinical benefit was shown in 30 % of patients, mostly due to reduction in pain, but this lasted for a limited time. Local complications (pancreatitis and pseudocyst formation) occurred in three patients; grade III hematologic toxicity occurred in three patients without serious clinical sequelae.Conclusions: EUS-guided intraoperative interstitial brachytherapy had a moderate local tumor effect and showed some clinical benefit in 30 % of the patients in this study. Combination of this form of treatment with external radiation and/or chemotherapy should be tested in future trials.

An overview on the use of information technology in agricultural water management is presented. This includes examples of past uses of databases, software and modeling, expert systems, real-time expert systems, and fuzzy logic, knowledge delivery systems, emerging technologies, and large-scale water management systems.

A programmable analog neural computer and selected applications are described. The machine was assembled from over 100 custom VLSI modules containing neurons, synapses, routing switches, and programmable synaptic time constants. Connection symmetry and modular construction allow expansion to arbitrary size. The network runs in real-time analog mode. Connection architecture as well as neuron and synapse parameters are controlled by a digital host that monitors the network performance through a digital/analog interface. Programming and monitoring software has been developed. Several application examples, including the dynamic decomposition of acoustical patterns, are described. The machine is intended to real-time, real-world computations. In current configuration its maximal speed is equivalent to that of a digital machine capable of more than 10/sup 12/ FLOPS. >

A multichip, programmable analog neural network for real-time dynamic computations is described. The network's interconnection structure, the neuron characteristics, synaptic connections, and synaptic time constant are modifiable. The chips are designed to allow a modular and expandable gross architecture that can be adjusted to the complexity of the task. The network operates fully analog in real time. However, a digital host is used to set the network parameters and monitor the neuron outputs. A prototype neural computer consisting of 72 neurons has been assembled and tested. The network has been successfully configured for several applications and found to have a performance that is equivalent to a digital machine of 10/sup 11/ FLOPS. >

Background MG53 preconditioning has been proven to protect the hearts against ischemia/reperfusion (I/R) injury, manifested mainly by reduced myocardial specific biomarker, and decreased infarct size. This study is to observe the effects of MG53 preconditioning on ischemia/reperfusion-induced arrhythmias in the Langendorff perfused rat hearts. Methods 24 healthy adult SD rats,were randomly divided into Sham group (group S), I/R group (group I/R), MG53 preconditioning group (group M), 8 in each group. In vitro heart was perfused for 20 min before the left coronary artery was occluded 30 min followed by 30 min reperfusion. Compared ECG, LDH of perfused fluid, myocardial infarct size was measured with TTC staining and expression of Caspase3 was measured with Western blot. Results Dring reperfusion period, compared with group I/R, the LDH in group M reduced significantly, group M had no ventricular fibrillation (VF), greatly decreased the times of ventricular premateure beat (VPB), shorten the duration of ventricular tachycardia (VT), reduced the incidence of ventricular tachycardia and the arrhythmia score. Myocardial infract size and expression level of Caspase had no significant change in two groups. Conclusions MG53 preconditioning paly a protection role on ischemia/reperfusion-induced arrhythmias in the isolated rat hearts.

University of PennsylvaniaDepartment of Electrical EngineeringandDepartment of Biochemistry and Biophysics#Philadelphia, PA 19104, USA This paper gives an overview of the principles andhardware realizations of artificial neural networks. The first section describes the operation of neural networks, using simple examples to illustrate someof its key properties. Next the different architectures are described, including single and multiple perceptron networks, Hopfield and Kohonen nets. A brief discussion of the learning rules employed infeedforward and feedback networks follows. The final section discusses hardware implementations of neural systems with emphasis on analog VLSI. Different approaches for the realizations of neurons and synapses are described. A brief comparison between analog and digital techniques is given. 1. INTRODUCTION Over the last decade, much research has been done on brain-like machines such as adaptive and learning systems, artificial neural systems, associative memories,fuzzy cognitive maps, array processors, parallel machines