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The COVID-19 pandemic has caused unprecedented health care challenges mandating surgical service reconfiguration. Within our hospital, emergency and elective streams were separated and self-contained Protected Elective Surgical Units were developed to mitigate against infection-related morbidity. Aims of this study were to determine the risk of COVID-19 transmission and mortality and whether the development of Protected Elective Surgical Units can result in significant reduction in risk.A retrospective observational study of consecutive patients from 18 specialties undergoing elective or emergency surgery under general, spinal, or epidural anaesthetic over a 12-month study period was undertaken. Primary outcome measures were 30-day postoperative COVID-19 transmission rate and mortality. Secondary adjusted analyses were performed to ascertain hospital and Protected Elective Surgical Unit transmission rates.Between 15 March 2020 and 14 March 2021, 9,925 patients underwent surgery: 6,464 (65.1%) elective, 5,116 (51.5%) female, and median age 57 (39-70). A total of 69.5% of all procedures were performed in Protected Elective Surgical Units. Overall, 30-day postoperative COVID-19 transmission was 2.8% (3.4% emergency vs 1.2% elective P .001). Protected Elective Surgical Unit postoperative transmission was significantly lower than non-Protected Elective Surgical Unit (0.42% vs 3.2% P .001), with an adjusted likely in-hospital Protected Elective Surgical Unit transmission of 0.04%. The 30-day all-cause mortality was 1.7% and was 14.6% in COVID-19-positive patients. COVID-19 infection, age 70, male sex, American Society of Anesthesiologists grade 2, and emergency surgery were all independently associated with mortality.This study has demonstrated that Protected Elective Surgical Units can facilitate high-volume elective surgical services throughout peaks of the COVID-19 pandemic while minimising viral transmission and mortality. However, mortality risk associated with perioperative COVID-19 infection remains high.

Myocardial perforation is a rare yet serious complication following cardiac pacemaker or defibrillator device procedures. In this article, the authors describe a case of right ventricular pacemaker lead perforation presenting to our hospital’s medical assessment unit with a clinical presentation suggestive of an acute pulmonary embolism. Treatment dose low molecular weight heparin (LMWH) was commenced while awaiting CT scan. CT images were negative for PE however demonstrated RV lead perforation. Echocardiogram demonstrated pericardial effusion with the tip of RV lead in the pericardial free space. A rapid deterioration in the patient’s haemodynamics prompted an emergency pericardial drain insertion and successful RV lead re-position in the cardiac catheter lab. The patient recovered well and was discharged with routine pacemaker clinic follow-up.

Successful academic-clinical partnerships are mutually beneficial for academic nursing and clinical organizations, supporting the long-term success of nursing programs while simultaneously improving patient outcomes. Advocated by the American Association of Colleges of Nursing in their 2016 report, Advancing Healthcare Transformation: New Era for Academic Nursing, this position paper provides six actions for transforming academic nursing. However, developing sustainable academic-practice models has proven challenging despite this roadmap, as research has not substantiated their benefits. This article describes an innovative academic-practice model that transitioned advanced practice registered nurses practicing at Le Bonheur Children's Hospital to full-time faculty, with a continued primary clinical practice role, in the College of Nursing at the University of Tennessee Health Science Center. We present the origin, development, and implementation of this academic-practice partnership model, offering recommendations for its replication by other universities and clinical agencies on this journey. Creating a sustainable model requires a shared vision, buy-in at all levels, frequent and transparent communication, planning that considers the individual policies of the partnering agencies, and persistence despite leadership changes. Two years into the partnership and remaining intact despite critical leadership changes within the clinical agency, the next phase of the relationship will permit us to document the model's impact on academic and clinical outcomes.

All UK H&I laboratories and transplant units operate under a single national kidney offering policy, but there have been variations in approach regarding when to undertake the pre-transplant crossmatch test. In order to minimize cold ischaemia times for deceased donor kidney transplantation we sought to find ways to be able to report a crossmatch result as early as possible in the donation process. A panel of experts in transplant surgery, nephrology, specialist nursing in organ donation and H&I (all relevant UK laboratories represented) assessed evidence and opinion concerning five factors that relate to the effectiveness of the crossmatch process, as follows: when the result should be ready for reporting; what level of donor HLA typing is needed; crossmatch sample type and availability; fairness and equity; risks and patient safety. Guidelines aimed at improving practice based on these issues are presented, and we expect that following these will allow H&I laboratories to contribute to reducing CIT in deceased donor kidney transplantation.

Background: Published findings on breast cancer risk associated with different types of menopausal hormone therapy (MHT) are inconsistent, with limited information on long-term effects. We bring together the epidemiological evidence, published and unpublished, on these associations, and review the relevant randomised evidence. Methods: Principal analyses used individual participant data from all eligible prospective studies that had sought information on the type and timing of MHT use; the main analyses are of individuals with complete information on this. Studies were identified by searching many formal and informal sources regularly from Jan 1, 1992, to Jan 1, 2018. Current users were included up to 5 years (mean 1·4 years) after last-reported MHT use. Logistic regression yielded adjusted risk ratios (RRs) comparing particular groups of MHT users versus never users. Findings: During prospective follow-up, 108 647 postmenopausal women developed breast cancer at mean age 65 years (SD 7); 55 575 (51%) had used MHT. Among women with complete information, mean MHT duration was 10 years (SD 6) in current users and 7 years (SD 6) in past users, and mean age was 50 years (SD 5) at menopause and 50 years (SD 6) at starting MHT. Every MHT type, except vaginal oestrogens, was associated with excess breast cancer risks, which increased steadily with duration of use and were greater for oestrogen-progestagen than oestrogen-only preparations. Among current users, these excess risks were definite even during years 1–4 (oestrogen-progestagen RR 1·60, 95% CI 1·52–1·69; oestrogen-only RR 1·17, 1·10–1·26), and were twice as great during years 5–14 (oestrogen-progestagen RR 2·08, 2·02–2·15; oestrogen-only RR 1·33, 1·28–1·37). The oestrogen-progestagen risks during years 5–14 were greater with daily than with less frequent progestagen use (RR 2·30, 2·21–2·40 vs 1·93, 1·84–2·01; heterogeneity p Interpretation: If these associations are largely causal, then for women of average weight in developed countries, 5 years of MHT, starting at age 50 years, would increase breast cancer incidence at ages 50–69 years by about one in every 50 users of oestrogen plus daily progestagen preparations; one in every 70 users of oestrogen plus intermittent progestagen preparations; and one in every 200 users of oestrogen-only preparations. The corresponding excesses from 10 years of MHT would be about twice as great.

The work presented in this paper details both an experimental program and an associated numerical modeling effort to characterize and predict the ballistic response of S-2 glass/SC15 epoxy composite panels. The experimental program consisted of ¼ inch diameter soft carbon steel spheres impacting ¼ and ½ inch thick flat composite panels at velocities ranging from 220 to 1570 m/s. High speed cameras were used to capture the impact event and resulting residual velocity of the spheres for each test configuration. After testing, each panel was inspected both visually and with ultrasonic C-scan techniques to determine the extent and depth of damage imparted on the panel by the impactor. The numerical modeling efforts utilized the anisotropic multi-constituent composite model (MCM) within the CTH shock physics hydrocode. The MCM model allows for evaluation of damage at the constituent level through continuum averaged stress and strain fields. The model also accounts for the inherent coupling of the equation of state and strength response that occurs in anisotropic composite materials. Finally, the simulation results are compared against the experimentally measured residual velocity as a quantitative metric and against the measured damage extent and patterns as a qualitative metric. The comparisons show good agreement in residual velocity and damage extent.

The phase transition of crystalline and amorphous silica materials to a stishovite-like high-pressure phase has received considerable interest. While most work has focused on pure SiO2 glass (fused silica), studies identifying a similar high-pressure phase transformation in soda-lime glass have not been performed. Marked differences in the network structure and compressibility of soda-lime glass as compared to fused silica raise questions as to how a stishovite transition might manifest in these glasses. In this work, new plate impact experiments on soda-lime glass have been performed to ∼110 GPa to measure the Hugoniot response in the high-pressure regime. Results of these tests were unable to find evidence of a transition to a high-pressure polymorph under shock loading. A glass constitutive model is proposed to capture this newly measured high-pressure response. Good agreement between time resolved measurements and simulation results from the CTH hydrocode with this model implemented are shown, along with additional insights into the apparent glass behavior.

This article details the implementation and application of the glass-specific computational constitutive model by Holmquist and Johnson (J Appl Mech 78:051003, 2011) to simulate the dynamic response of soda-lime glass under high rate and high pressure shock conditions. The predictive capabilities of this model are assessed through comparison of experimental data with numerical results from computations using the CTH shock physics code. The formulation of this glass model is reviewed in the context of its implementation within CTH. Using a variety of experimental data compiled from the open literature, a complete parameterization of the model describing the observed behavior of soda-lime glass is developed. Simulation results using the calibrated soda-lime glass model are compared to flyer plate and Taylor rod impact experimental data covering a range of impact and failure conditions spanning an order of magnitude in velocity and pressure. The complex behavior observed in the experimental testing is captured well in the computations, demonstrating the capability of the glass model within CTH.

Background: Cancer Antigen 125 (CA125) is currently the best available ovarian cancer screening biomarker. However, CA125 has been limited by low sensitivity and specificity in part due to normal variation between individuals. Personal characteristics that influence CA125 could be used to improve its performance as screening biomarker. Methods: We developed and validated linear and dichotomous (≥35 U/mL) circulating CA125 prediction models in postmenopausal women without ovarian cancer who participated in one of five large population-based studies: Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO, n = 26,981), European Prospective Investigation into Cancer and Nutrition (EPIC, n = 861), the Nurses' Health Studies (NHS/NHSII, n = 81), and the New England Case Control Study (NEC, n = 923). The prediction models were developed using stepwise regression in PLCO and validated in EPIC, NHS/NHSII and NEC. Result: The linear CA125 prediction model, which included age, race, body mass index (BMI), smoking status and duration, parity, hysterectomy, age at menopause, and duration of hormone therapy (HT), explained 5% of the total variance of CA125. The correlation between measured and predicted CA125 was comparable in PLCO testing dataset (r = 0.18) and external validation datasets (r = 0.14). The dichotomous CA125 prediction model included age, race, BMI, smoking status and duration, hysterectomy, time since menopause, and duration of HT with AUC of 0.64 in PLCO and 0.80 in validation dataset. Conclusions: The linear prediction model explained a small portion of the total variability of CA125, suggesting the need to identify novel predictors of CA125. The dichotomous prediction model showed moderate discriminatory performance which validated well in independent dataset. Our dichotomous model could be valuable in identifying healthy women who may have elevated CA125 levels, which may contribute to reducing false positive tests using CA125 as screening biomarker. © 2019 The Author(s).

Background: Cancer antigen 125 (CA125) is the most promising ovarian cancer screening biomarker to date. Multiple studies reported CA125 levels vary by personal characteristics, which could inform personalized CA125 thresholds. However, this has not been well described in premenopausal women. Methods: We evaluated predictors of CA125 levels among 815 premenopausal women from the New England Case Control Study (NEC). We developed linear and dichotomous (-35 U/mL) CA125 prediction models and externally validated an abridged model restricting to available predictors among 473 premenopausal women in the European Prospective Investigation into Cancer and Nutrition Study (EPIC). Results: The final linear CA125 prediction model included age, race, tubal ligation, endometriosis, menstrual phase at blood draw, and fibroids, which explained 7% of the total variance of CA125. The correlation between observed and predicted CA125 levels based on the abridged model (including age, race, and menstrual phase at blood draw) had similar correlation coefficients in NEC (r = 0.22) and in EPIC (r= 0.22). The dichotomous CA125 prediction model included age, tubal ligation, endometriosis, prior personal cancer diagnosis, family history of ovarian cancer, number of miscarriages, menstrual phase at blood draw, and smoking status with AUC of 0.83. The abridged dichotomous model (including age, number of miscarriages, menstrual phase at blood draw, and smoking status) showed similar AUCs in NEC (0.73) and in EPIC (0.78). Conclusions: We identified a combination of factors associated with CA125 levels in premenopausal women. Impact: Our model could be valuable in identifying healthy women likely to have elevated CA125 and consequently improve its specificity for ovarian cancer screening. © 2019 American Association for Cancer Research.

We demonstrate single-shot multi-frame imaging of quasi-2D cylindrically converging shock waves as they propagate through a multi-layer target sample assembly. We visualize the shock with sequences of up to 16 images, using a Fabry-Perot cavity to generate a pulse train that can be used in various imaging configurations. We employ multi-frame shadowgraph and dark-field imaging to measure the amplitude and phase of the light transmitted through the shocked target. Single-shot multi-frame imaging tracks geometric distortion and additional features in our images that were not previously resolvable in this experimental geometry. Analysis of our images, in combination with simulations, shows that the additional image features are formed by a coupled wave structure resulting from interface effects in our targets. This technique presents a new capability for tabletop imaging of shock waves that can be extended to experiments at large-scale facilities.

In many structural applications the use of composite material systems in both retrofit and new design modes has expanded greatly. The performance benefits from composites such as weight reduction with increased strength, corrosion resistance, and improved thermal and acoustic properties, are balanced by a host of failure modes whose genesis and progression are not yet well understood. As such, structural health monitoring (SHM) plays a key role for in-situ assessment for the purposes of performance/operations optimization, maintenance planning, and overall life cycle cost reduction. In this work, arrays of fiber Bragg grating optical strain sensors are attached to glass-epoxy solid laminate composite specimens that were subsequently subjected to specific levels of fully reversed cyclic loading. The fatigue loading was designed to impose strain levels in the panel that would induce damage to the laminate at varying numbers of cycles. The objectives of this test series were to assess the ability of the fiber Bragg grating sensors to detect fatigue damage (using previously developed SHM algorithms) and to establish a dataset for the development of a prognostic model to be applied to a random magnitude of fully reversed strain loading. The prognostic approach is rooted in the Failure Forecast Method, whereby the periodic feature rate-of-change was regressed against time to arrive at a failure estimate. An uncertainty model for the predictor was built so that a probability density function could be computed around the time-of-failure estimate, from which mean, median, and mode predictors were compared for robustness.

On-going research into the complexities of polyurea behavior under shock loading has led to some breakthroughs in the predictive simulation of how this nominally soft polymer responds under high velocity impact conditions. This work expands upon a previously reported modified pressure-dependent viscoelastic constitutive model for polyurea and its performance under ballistic impact. Specifically, we present recent enhancements to the model including nonlinearites in the Hugoniot and improvements in the high-temperature viscoelastic behavior, which substantially improves accuracy and extends the model’s range of applicable conditions. These improvements are demonstrated through correlation of computations for a suite of normal and pressure-shear plate impact experiments well documented in the open literature. Additionally, microparticle impact experiments were performed on polyurea using a laser-induced particle impact test (LIPIT) technique. High-speed imaging of the impact mechanics revealed elastic particle rebound at low velocity but penetration at high velocity. Simulation of these LIPIT experiments demonstrates good accuracy of the polyurea model under these conditions as well as provides insight into the mechanisms governing the results observed.

Composite materials are used as alternatives to conventional metallics in a multitude of applications including military ground vehicles, aircraft, space launch and re-entry vehicles and even personnel protection where weight savings are critical. In application, these materials are susceptible to high velocity impacts from various threats and it is essential that the response of these materials, under relevant conditions, be understood in order to provide optimized effective designs. This work details an on-going effort to validate the anisotropic multiple constituent model (MCM) within the CTH hydrocode. Within the CTH framework, the anisotropic MCM model is coupled with an equation of state (EOS) and provides continuum averaged stress and strain fields for each constituents (fiber and resin) of a composite microstructure from which progressive damage evaluations can be performed. In this paper we focus on recent validation efforts where woven S2/SC15 (glass/epoxy) composite panels were impacted with steel spheres at various impact velocities and angles of obliquity. The experimental testing was performed at the Shock Thermodynamics Applied Research (STAR) Facility at Sandia National Laboratories to provide data for further validation of the MCM model under oblique impact conditions. Oblique impacts result in stress fields which exercise the anisotropy of the strength model and the EOS coupling of the MCM model more robustly. Results are presented for both the CTH MCM model predictions and the experimental testing. The primary comparison metrics evaluated are the predicted and observed damage extent, overall damage pattern, and residual velocity of the projectile.

This paper details a numerical modeling and experimental test program focused on high energy ballistic impacts on composite rib-stiffened structures. The numerical model used in this paper is designated as the Multiconstituent Composite Model (MCM), which is implemented within the CTH shock physics code for simulation of ballistic impact damage on composite structures. The presented work utilized a building block approach, where component level flat panels were studied first, followed by sub-structure level T-joint specimens, both fabricated from a carbon/epoxy composite material. All numerical studies and experimental tests utilized the military grade 0.50 caliber M2 Ball round as a projectile. Following testing, each panel was inspected both visually and using Ultrasonic C-Scan techniques to determine the extent of damage sustained upon impact. Finally, comparisons of the experimental data with the numerical predictions are presented and discussed. Both the flat panel and T-joint damage predictions were in good agreement with the experimental data.

Impact loading response of unidirectional and plain weave fiber reinforced polymer composite materials is typically modeled using a Lagrangian method such as the finite element method. However, these methods often lack a coupled equation of state. In anisotropic materials, the pressure (equation of state) and deviatoric (strength) portions of the stress tensor are coupled: a shear stress can produce a volumetric response and a volumetric strain can produce a shear stress. High-velocity impacts of composite materials instigate a coupled pressure and stress response, so an equation of state is important in determining the non-uniform stress response of the material. A new composite model, which couples the pressure response to the constitutive response of the material, has been implemented in an Eulerian large deformation, strong shock wave, solid mechanics code. Experiments of steel projectiles perforating composite targets were numerically simulated to begin to validate this new composite model. This paper will discuss the coupled equation of state and strength response, and compare the results of these experiments with the results predicted by the model.

The longitudinal strain and polarization of a soft polycrystalline ferroelectric ceramic (lead zirconate titanate, PZT) were measured under uniaxial compressive stress at elevated temperatures utilizing a novel testing fixture. Ferroelectric ceramics have not previously been characterized under these conditions due to experimental complexity. In addition to nonlinear macroscopic constitutive behavior, the linear elastic moduli have been measured throughout the loading cycle, allowing for the determination of the relative contributions from the linear and nonlinear ferroelastic behavior as a function of stress and temperature. Experimental results show a strong temperature dependence of ferroelastic switching. The ferroelastic properties of unpoled and poled materials for temperatures up to the Curie point are contrasted with the spontaneous strain, elucidating the role of tetragonality in ferroelastic switching. When thermal changes are considered, marked changes in the maximum strain are observed.

Failure of composite materials often results from damage accumulation in the individual constituents (fiber and matrix) of the composite. At times, damage may even be limited to a single constituent. The ability to accurately predict not only ultimate strength values but also intermediate constituent level failures is crucial to the success of introducing composite materials into demanding structural applications. In this paper, we develop two progressive failure models for the analysis of a plain weave composite material. The formulations are based on treating the weave as consisting of separate but linked continua representing the warp fiber bundles, fill fiber bundles, and pure matrix pockets. Retaining constituent identities allows one to access constituent (phase averaged) stress fields that are used in conjunction with both a stress based and damage based failure criterion to construct a nonlinear progressive failure algorithm for the woven fabric composite material. The MCT decomposition and the nonlinear progressive failure algorithm are incorporated within the framework of a traditional finite element analysis. The constituent based progressive failure algorithm combined with both the stress based and damage based failure criteria are compared against experimental data for a plain weave, woven fabric composite under various loading conditions. The analytical results from the damage based approach show a marked improvement over the stress based predictions and are in excellent agreement with the experimental data.

April 2005 marked the fifth anniversary of the adoption of ANSI/MSE 2000, the Management System for Energy. As required by American National Standard Institute (ANSI) procedures, this national standard was revised and again approved by a national review board during the year. To make the standard easier to understand and implement, the format was revised to a process model based on the “plan-do-check-act” process. This change keeps ANSI/MSE 2000:2005 compatible with the current ISO 9001 (quality management) and 14001 (environmental management) standards. This review of revisions includes the reasoning behind each change or addition and the application of changes. An accompanying standard, The Guide to Implementing ANSI/MSE 2000, is also presented and discussed.

Multicontinuum theory (MCT) is based on the two-constituent decomposition developed by Hill [Hill R. Elastic properties of reinforced solids: some theoretical principles. J Mech Phys Sol 1963;11:357–72] to calculate the constituent level stress/strain fields of a composite material from the ‘smeared’ composite stress/strain fields. The work presented in this paper expands previous isothermal MCT work to include thermal effects related to large temperature gradients caused by fires. Analytical fire conditions are simulated using a 1-D heat diffusion equation, which provides time-dependent temperature gradients through the thickness of the composite. Results illustrate that when the composite materials are subjected to extreme thermal conditions, the thermal residual stresses resulting from the fiber and matrix coefficient of thermal expansion mismatch are significant. Progressive failure simulations are performed using the thermal–mechanical MCT algorithm, in which an increased rate of failure is observed for a composite material when it is subjected to large external temperature gradients similar to those experienced in fire environments.

An accurate assessment of accumulative damage of a composite ship structure subjected to fire is strongly reliant on the accurate characterization of the time dependent temperature distribution within the composite system. Current state-of-the-art analysis tools assume that thermal–mechanical properties of composite structures are independent of temperature change and mass loss. In this paper, a temperature and mass dependent heat diffusion model is developed to characterize the temperature and mass dependent heat conduction, energy consumption resulting from the decomposition, and the energy transfer associated with vaporous migration. The temperature dependent thermal conductivity and specific heat capacity are determined for the composite at a given resin decomposition stage using a recently developed small-scale test apparatus. Given the temperature dependent thermal properties of the fiber and resin materials, the resulting temperature dependent thermal properties of a woven fabric composite are computed from the newly developed thermal–mechanical analysis tool (TMAT). To assess the effect of using single heating rate based mass loss on the composite fire response prediction, the kinetic parameters are obtained from the post-processing of thermogravimetric analysis (TGA) test data conducted at various heating rates. The effects of temperature dependent thermal conductivity, specific heat capacity, and kinetic parameters determined at different heating rates are explored through the application of the temperature and mass dependent fire model to a composite plate subjected to a hydrocarbon fire. The accuracy of the temperature and mass dependent thermal model is demonstrated by comparing its response prediction with available experimental data.

The inability to accurately predict the onset of failure in modern fabric-reinforced composite materials has hindered the implementation of these materials into the mainstream applications. Excessive qualification and structural testing must be performed on composite members as a result of uncertainty in the performance of the material, resulting in significantly higher expenses associated with these materials. This situation can only be improved through the rigorous development of both improved failure and material response prediction capabilities and improved experimental verification. The current study addresses these issues, as well as explores recent developments in numerical predictions and experimental techniques. A combined numerical investigation of damage initiation mechanics and experimental verification of predicted results for a woven glass–vinyl ester composite material is performed. More specifically, 18-oz biased (5 warp/4 fill rovings) plain weave E-glass–vinyl ester laminate with warp rovings oriented in [0/90]s and [0/90/±45]s configurations are investigated. Experimental data for the E-glass–vinyl ester [0/90]s laminate is summarized in a two-dimensional biaxial failure envelope. The feasibility of using thickness-tapered cruciform specimens for generating the experimental biaxial test data is also addressed. Finally, numerical predictions of failure of the fabric-reinforced laminate are developed and compared against the experimental failure envelope for the cross-ply laminate.

C&A Floorcoverings has long had a business strategy of environmental stewardship. So when its management heard of the new ANSI national standard for the management of energy, it was a natural extension of both corporate environmental policy and the desire to plan and sustain the savings from energy projects. ANSI/MSE 2000: A Management System for Energy, is a management standard that provides both the support and the flexibility needed to institute and sustain an energy management system that aligns management energy policy, energy goals, targets, and projects with business objectives. A dialogue between a developer of the standard and an implementer of the standard in an industrial facility highlights the successes and difficulties encountered along the way. MSE 2000 was developed and written by expert staff from the Georgia Tech EDI Energy and Environmental Management Center (EEMC) to address common problems seen over its 25-year history. As a member of the EEMC Advisory Board, C&A Floorcoverings was exposed to MSE 2000 while it was still in a draft format. Because this approach fit in so well with its overall business objectives, management supported implementation of the standard in the plant. Resulting changes to energy efficiency and conservation efforts are highlighted, including the development of documentation and follow-up of project results. Implementation has been slow, due to the difficulties in focusing tight resources on the implementation, but management has actively participated in the development of a formal energy policy and approved energy goals and targets. This involvement guarantees that management objectives will drive the energy management system. Regular management reviews of results are held to ensure that this alignment continues. The result has been sustainable savings in energy consumption and costs, as well as continued improvement in energy operations. Because of the alignment with management objectives, the system has other benefits as well, such as a measurable decrease in environmental impacts and the active encouragement of sustainable energy sources.

An ongoing challenge within the structural analysis community is to accurately predict damage and progressive failure in large-scale structural components composed of composite materials. Multicontinuum technology (MCT) provides a means to produce constituent (fiber and matrix) level stress and strain information within the framework of commercial finite element analysis. Constituent level stress/strain information forms the basis for a progressive failure algorithm that has successfully been used to predict coupon failure in a wide range of composite materials and laminate configurations. In this paper, MCT is used to analyze the failure of rib-stiffened panels associated with advanced composite grid-stiffened structure (AGS) designs. More specifically, MCT is used to predict and analyze the separation of the rib to skin interface for comparison with tee pulloff and tee bend test data. Predictions for the initial and final separation of the rib to skin interfaces are shown to be in good agreement with experimental test data. The results also lend insight into design and manufacturing considerations that are key to the strength and performance of the rib to panel interface.

Multicontinuum theory (MCT) refers to the use of phase averaged constituent stress/strain fields for predicting failure in composite structural analysis. Given the composite material mechanical properties as well as those of the constituents, well known closed form algebraic expressions exist to decompose the composite stress/strain fields down to the constituent level. Recent research indicates constituent based failure algorithms show a great deal of promise in predicting material failure when coupled to nonlinear finite element codes. A limitation of MCT is that the traditional constituent decomposition is only valid for materials composed of two constituents. In this paper, the MCT decomposition is generalized to handle composite materials composed of three constituents. The application of interest is a woven fabric composite material. The three constituents consist of the warp bundles, fill bundles, and pure matrix pockets. Numerical results are presented for the proposed three-constituent decomposition and are shown to be in good agreement with phase averaged stresses obtained from direct volume averaging of finite element micromechanics models.

There is limited evidence on the association between dietary folate intake and the risk of breast cancer (BC) by hormone receptor expression in the tumors. We investigated the relationship between dietary folate and BC risk using data from the European Prospective Investigation into Cancer and Nutrition (EPIC). A total of 367993 women age 35 to 70 years were recruited in 10 European countries. During a median follow-up of 11.5 years, 11575 women with BC were identified. Dietary folate intake was estimated from country-specific dietary questionnaires. Cox proportional hazards regression models were used to quantify the association between dietary variables and BC risk. BC tumors were classified by receptor status. Subgroup analyses were performed by menopausal status and alcohol intake. Intake of other B vitamins was considered. All statistical tests were two-sided. A borderline inverse association was observed between dietary folate and BC risk (hazard ratio comparing top vs bottom quintile [HRQ5-Q1] = 0.92, 95% CI = 0.83 to 1.01, P (trend) = .037). In premenopausal women, we observed a statistically significant trend towards lower risk in estrogen receptor-negative BC (HRQ5-Q1 = 0.66, 95% CI = 0.45 to 0.96, P (trend) = .042) and progesterone receptor-negative BC (HRQ5-Q1 = 0.70, 95% CI = 0.51 to 0.97, P (trend) = .021). No associations were found in postmenopausal women. A 14% reduction in BC risk was observed when comparing the highest with the lowest dietary folate tertiles in women having a high (> 12 alcoholic drinks/week) alcohol intake (HRT3-T1 = 0.86, 95% CI = 0.75 to 0.98, P (interaction) = .035). Higher dietary folate intake may be associated with a lower risk of sex hormone receptor-negative BC in premenopausal women.

Chronic villitis is a common condition in human placentae. In some cases an infectious cause can be demonstrated, such as infection with cytomegalovirus and rubella virus. Most often it is of unknown aetiology, the so-called VUE (villitis of unknown aetiology). We describe two cases with identification of specific infectious agents, each demonstrating previously unreported findings, i.e. persistent varicella antigen in the villi in case 1, and presence of toxoplasma cysts in Wharton's jelly in case 2. The identification of the pathogens, varicella virus and toxoplasma, would easily have been overlooked in routine study of the placenta and were possible because of clinical suspicion.

Experimental and epidemiological evidence suggests that prolactin might play a role in the etiology of breast cancer. We analyzed the relationship of prediagnostic circulating prolactin levels with the risk of breast cancer by menopausal status, use of postmenopausal hormone replacement therapy (HRT) at blood donation, and by estrogen and progesterone receptor status of the breast tumors. Conditional logistic regression was used to analyze the data from a case-control study nested within the prospective European EPIC cohort, including 2250 invasive breast cancer and their matched control subjects. Statistically significant heterogeneity in the association of prolactin levels with breast cancer risk between women who were either pre- or postmenopausal at the time of blood donation was observed (P-het = 0.04). Higher serum levels of prolactin were associated with significant increase in the risk of breast cancer among postmenopausal women [odds ratio (OR)(Q4-Q1) = 1.29 (95% confidence interval, CI, 1.05-1.58), P-trend = 0.09]; however, this increase in risk seemed to be confined to women who used postmenopausal HRT at blood donation [ORQ4-Q1 = 1.45 (95% CI 1.08-1.95), P-trend = 0.01], whereas no statistically significant association was found for the non-users of HRT [ORQ4-Q1 = 1.11 (95%CI 0.83-1.49), P-trend = 0.80] (P-het = 0.08). Among premenopausal women, a statistically non-significant inverse association was observed [ORQ4-Q1 = 0.70 (95% CI 0.48-1.03), P-trend = 0.16]. There was no heterogeneity in the prolactin-breast cancer association by hormone receptor status of the tumor. Our study indicates that higher circulating levels of prolactin among the postmenopausal HRT users at baseline may be associated with increased breast cancer risk.

Cancer of unknown primary site (CUP) may be called an "orphan" disease, as it is diagnosed when metastases are detected while the primary tumor typically remains undetected, and because little research has been done on its primary causes. So far, few epidemiological studies, if any, have addressed possible risk factors for CUP. We analyzed data from the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort (N 5 476,940). During prospective follow-up, a total of 651 cases of incident cases of CUP were detected (ICD-O-2 code C809). Proportional hazards models were conducted to examine the associations of lifetime history of smoking habits, alcohol consumption, levels of education and anthropometric indices of adiposity with risk of being diagnosed with CUP. Risk of being diagnosed with CUP was strongly related to smoking, with a relative risk of 3.66 [95% C.I., 2.24-5.97] for current, heavy smokers (26+ cigarettes/day) compared to never smokers (adjusted for alcohol consumption, body mass index, waist circumference and level of education) and a relative risk of 5.12 [3.09-8.47] for cases with CUP who died within 12 months. For alcohol consumption and level of education, weaker associations were observed but attenuated and no longer statistically significant after adjusting for smoking and indices of obesity. Finally, risk of CUP was increased by approximately 30 per cent for subjects in the highest versus lowest quartiles of waist circumference. Our analyses provide further documentation, in addition to autopsy studies, that a substantial proportion of cancers of unknown primary site may have their origin in smoking-related tumors, in particular. © 2014 UICC.

A novel allele, human leukocyte antigen (HLA)-A*6824, has been identified in three unrelated individuals of northwestern European origin in a period of less than 4 months, implying that this allele may be quite common in this population. HLA-A*6824 differs from A*680102 by a single nucleotide change at position 275 in exon 2, which results in a conservative amino acid substitution from lysine to arginine in the peptide-binding groove at codon 68.

Background: Two recent genome-wide association studies (GWAS) of pancreatic ductal adenocarcinoma (PDAC), conducted, respectively, in a Japanese and in a Chinese population, identified eight novel loci affecting PDAC risk. Methods: We attempted to replicate the novel loci in a series of PDACs and healthy controls of European ancestry in the context of the newly formed PANcreatic Disease ReseArch (PANDoRA) consortium. We genotyped seven single-nucleotide polymorphisms (SNP): rs12413624, rs1547374, rs372883, rs5768709, rs6464375, rs708224, rs9502893 (one SNP identified in the Chinese GWAS is not polymorphic in Caucasians) in 1,299PDACcases and 2,884 controls.Wealso attempted stratified analysis considering the different stages of the disease and addressed the possible involvement of the selected SNPs on the survival of patients. Results: None of the SNPs were significantly associated with PDAC risk if considering the overall population of the consortium. When stratifying for country of origin, we found that in the Polish subgroup, the G allele of rs372883 was statistically significantly associated with increased risk [OR, 6.40;95% confidence interval (CI), 2.28-17.91]. However, the sample size of the subgroups was rather small; therefore, this result can be due to chance. None of the SNPs was associated with disease progression or survival. Conclusions: None of the SNPs associated with PDAC risk in two Asian populations were convincingly associated with PDAC risk in individuals of European descent. Impact: This study illustrates the importance of evaluation of PDAC risk markers across ethnic groups. © 2012 American Association for Cancer Research.

An alternative composite material failure model utilizing multicontinuum theory (MCT) is compared against experimental dynamic testing results. The investigation examines the advantages of the failure model, along with current model limitations. The experimental procedure used as the control data involved testing solid laminate glass reinforced plastic (GRP) composite specimen of varying thickness under a similar dynamic load. The testing subjected the solid laminate specimen to an air-backed, dynamic pressure load environment. All of the composite specimens were fitted with strain gauges on both the dry and wet surface of the specimen. Post test experimental analysis consisted of nondestructive ultrasonic (UT) evaluations to determine the damaged regions of the specimens. Experimental strain results and UT failure regions are compared with the composite material failure model.

Objective To examine the association between fruit and vegetable consumption and risk of different histological subtypes of lung cancer among participants of the European Prospective Investigation into Cancer and Nutrition study. Methods Multivariable Cox proportional hazard models were used to analyze the data. A calibration study in a subsample was used to reduce dietary measurement errors. Results During a mean follow-up of 8.7 years, 1,830 incident cases of lung cancer (574 adenocarcinoma, 286 small cell, 137 large cell, 363 squamous cell, 470 other histologies) were identified. In line with our previous conclusions, we found that after calibration a 100 g/day increase in fruit and vegetables consumption was associated with a reduced lung cancer risk (HR 0.94; 95% CI 0.89-0.99). This was also seen among current smokers (HR 0.93; 95% CI 0.90-0.97). Risks of squamous cell carcinomas in current smokers were reduced for an increase of 100 g/day of fruit and vegetables combined (HR 0.85; 95% CI 0.76-0.94), while no clear effects were seen for the other histological subtypes. Conclusion We observed inverse associations between the consumption of vegetables and fruits and risk of lung cancer without a clear effect on specific histological subtypes of lung cancer. In current smokers, consumption of vegetables and fruits may reduce lung cancer risk, in particular the risk of squamous cell carcinomas.

The composite material research and development performed over the last year has greatly enhanced the capabilities of CTH for non-isotropic materials. The enhancements provide the users and developers with greatly enhanced capabilities to address non-isotropic materials and their constitutive model development. The enhancements to CTH are intended to address various composite material applications such as armor systems, rocket motor cases, etc. A new method for inserting non-isotropic materials was developed using Diatom capabilities. This new insertion method makes it possible to add a layering capability to a shock physics hydrocode. This allows users to explicitly model each lamina of a composite without the overhead of modeling each lamina as a separate material to represent a laminate composite. This capability is designed for computational speed and modeling efficiency when studying composite material applications. In addition, the layering capability also allows a user to model interlaminar mechanisms. Finally, non-isotropic coupling methods have been investigated. The coupling methods are specific to shock physics where the Equation of State (EOS) is used with a nonisotropic constitutive model. This capability elastically corrects the EOS pressure (typically isotropic) for deviatoric pressure coupling for non-isotropic materials.

The U.S. Department of Energy launched the Renewable Systems Interconnection (RSI) study in 2007 to address the challenges to high penetrations of distributed renewable energy technologies. The RSI study consists of 14 additional reports.

The rapidly growing acceptance of Elastic Memory Composite (EMC) materials for deployable space structures illustrates the fact that EMC materials offer substantial performance improvements over existing spaceflight-qualified materials. This growing acceptance has, however, revealed a pressing need for further advancement of models to accurately predict key, non-classical, aspects of the material’s behavior. A critical deformation mechanism dominating the bending response of EMC materials at elevated temperatures is fiber microbuckling occurring within the softened resin. This paper will focus on analysis efforts aimed at predicting the geometric nonlinear response of EMC materials loaded in bending including fiber microbuckling. The analysis is based on a finite strain (Lagrangian) micromechanics analysis of a lamina in bending with an initial fiber waviness. Comparison of analytical predictions to experimental results for structural applications are provided.

In this paper, we examine a modified mechanics of materials based approach for predicting average interlaminar shear stress adjacent to free edges in laminated composite structures. Finite element models are constructed to study the free edge Interlaminar Shear Stress (ILSS) response of laminates under both tensile and bending loading conditions. Based on the finite element model results it was observed that the average ILSS for a bending condition was less than that for a pure membrane loading condition for the same local in-plane strain. The results also showed that the location of the lamina interface relative to the neutral axis influenced the difference between the bending and membrane induced free edge ILSS. Motivated by the work of Joo and Sun 1 who treated the membrane loading case only, an analytical expression is proposed for predicting free edge ILSS due to bending. Unlike the expression developed by Joo and Sun, the expression proposed here for critical interface ILSS for bending is not a simple linear function of the extension-shear coupling coefficients. The agreement with finite element results is very good.

Blood concentrations of insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-3 (IGFBP-3) have recently been associated with breast cancer risk, notably in women who developed breast cancer at a young age. Prospective studies published so far, however, were relatively small and odds ratio (OR) estimates imprecise. We present the results of a large prospective case-control study nested within the European Prospective Investigation into Cancer and Nutrition on total IGIF-I, IGFBP-3 and breast cancer risk including 1081 incident cases of invasive breast cancer and 2098 matched control subjects. Increasing IGF-I and IGFBP-3 concentrations were associated with a significant increase in breast cancer risk in women who developed breast cancer after 50 years of age (highest vs lowest quintile OR 1.38 (95% confidence interval (CI) 1.02-1.86), P = 0.01, and 1.44 (95% CI 1.04-1.98), P = 0.01, respectively), but no relationship was observed in younger women (OR = 1.03 (95% CI 0.60-1.77), P = 0.81 for IGF-I, and OR = 0.92 (95% CI 0.50-1.70), P = 0.69 for IGFBP-3). There was, however, significant heterogeneity in the relationship of breast cancer with serum IGF-I and IGFBP-3 levels depending on the time interval between blood donation and tumor diagnosis. A reduction in breast cancer risk with increasing IGF-I concentrations was observed in cases with a diagnosis of cancer less than 2 years after blood donation, (OR = 0.76 (95% CI 0.57-1.03)), while an increase in risk was observed for women with a later diagnosis (above or equal to two years after blood collection, OR = 1.51 (95% CI 1.19-1.91)). A similar pattern was observed for IGFBP-3. This study confirms previous findings for an association of serum IGF-I and IGFBP-3 concentrations with breast cancer risk, particularly for women with a later diagnosis of cancer, but it does not support the hypothesis of an involvement of IGF-I in younger women.

Vitamin C is an antioxidant and inhibitor of carcinogenic N-nitroso compound production in the stomach. Higher dietary vitamin C consumption is associated with decreased risk of gastric cancer (GC) in numerous case-control studies, but data from prospective studies are limited, particularly so for blood measures of vitamin C. The objective of this study was to determine the association of plasma and dietary vitamin C levels with the risk of GC in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition (EPIC), a large cohort involving 10 European countries. Using a fluorometric method, vitamin C was measured in pre-diagnostic plasma from 215 GC cases (matched controls = 416). Conditional logistic regression models adjusted by body mass index, total energy intake, smoking status/ duration/intensity and Helicobacter pylori infection status were used to estimate relative cancer risks. No association with GC risk was observed for dietary vitamin C, whereas an inverse GC risk was observed in the highest versus lowest quartile of plasma vitamin C [odds ratio (OR) = 0.55, 95% confidence interval (CI) = 0.31-0.97, Ptrend = 0.043], which was maintained after exclusion of cases with ≤2 years follow-up (OR = 0.40, 95% CI = 0.19-0.83, Ptrend = 0.064). The inverse association was more pronounced in subjects consuming higher levels of red and processed meats, a factor that may increase endogenous N-nitroso compound production. The effect of plasma vitamin C was not different by GC anatomical subsite (cardia/non-cardia) or histological subtype (diffuse/intestinal), and there was no significant interaction of effect with H.pylori. The results of this study show, in a prospective setting, an inverse association of GC risk with high levels of plasma vitamin C and suggest an interaction with the intake of red and processed meats, whose consumption may elevate endogenous N-nitroso compound production. © 2006 Oxford University Press.