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There are consequences of moving quickly in this world. Here we investigate how two very different species, mantis shrimp (Odontodactylus scyllarus) and cane toads (Bufo marinus), negotiate forces that result from moving rapidly in different environments. To study the mechanical principles and fluid dynamics of ultrafast power-amplified systems, we built Ninjabot, a physical model of the extremely fast mantis shrimp. While mantis shrimp produce damaging cavitation upon impact with their prey, they do not cavitate during the forward portion of their strike despite extreme speeds. In order to study cavitation onset in non-linear flows common during the mantis shrimp strike, we used Ninjabot to produce strikes of varying kinematics and measured cavitation presence or absence. We found that in rotating and accelerating biological conditions, cavitation inception is best explained only by maximum linear velocity. Thus, studies of cavitation onset in biological conditions only need to focus on maximum velocity. On land, moving quickly requires avoiding or preparing for impact with other objects, often the ground. Within anurans (frogs and toads), a group well known for jumping, cane toads are known to perform particularly controlled landings in which the forelimbs are used to decelerate and balance the body after impact as the hind limbs are lowered to the ground. Here I explore whether and how toads modulate landing preparation depending on hopping and landing conditions and what this can tell us about how they utilize sensory information to help them perform controlled landings. We found that toads modulate three components of impact preparation to specific hop conditions: 1) They position the forelimbs to hit the ground first by protracting and abducting the humeri, 2) They prepare and brace for impact by extending the elbows and activating underlying musculature to stiffen the joint and 3) they control torques during the landing by retracting the hind limbs and rotating the forelimbs to align with the impact angle. By perturbing landing conditions we found that toads tune these components to specific landing conditions with a combination of passive and active control and toads do so by primarily relying on non-visual sensory feedback.

We compared the diagnostic accuracy of emergency medicine residents (EMRs) and radiology residents (RRs) in performing focused abdominal sonography for trauma (FAST). The cohort in this prospective study comprised 200 unstable patients (163 males and 37 females; mean ± standard deviation of age, 34.3 ± 16.4 y) who presented with trauma. These patients were evaluated using FAST, first by EMRs and subsequently by RRs. Patients with positive FAST results underwent further diagnostic procedures such as computed tomography, diagnostic peritoneal lavage and laparotomy. Those with negative FAST results underwent clinical follow-up for 72 h until their condition deteriorated or they were discharged. Sensitivity, specificity, positive and negative predictive values and accuracy in evaluating free intraperitoneal fluid were 80%, 95%, 57%, 98% and 94% when FAST was performed by EMRs and 86%, 95%, 59%, 98% and 94% when FAST was performed by RRs. The level of agreement between EMRs and RRs was moderate (κ = 0.525). FAST is a useful screening tool for initial assessment of free abdominal fluid in patients with trauma. Our results indicate that EMRs can perform sonography on trauma patients as successfully as RRs.

Excessively fouled ballast can result a high amount of plastic settlement and reduction of vertical and lateral resistance of the track. A significant portion of railroad maintenance costs is associated with degraded fouled ballast. Therefore, it is important to understand the effects of ballast fouling at different moisture levels on the behavior of ballast under repeated loading conditions. Development of the testing equipment and procedure to better simulate and evaluate the performance of ballast under heavy loading and high traffic conditions can help the railroad industry to better understand the track risk factors. In this study a modified railroad ballast box test apparatus has been used to evaluate the effect of fouling on the plastic deformation of ballast in different moisture conditions up to 2,500,000 cycles, or the equivalent of 300MGT of heavy axle load traffic. The tests have been conducted under equivalent Heavy-Axle Load (HAL) loading conditions and for ballasts with

International audience; Aim: Patients with diabetes are at greater risk of cardiovascular events. Insulin resistance (IR) and hyperinsulinaemia are both related to an increased cardiovascular risk, but whether IR predicts coronary heart disease (CHD) independently of other risk factors in patients with type 2 diabetes (T2D) is a topic of considerable controversy. The aim of the present study was to evaluate the prospective relationship of fasting insulin, HOMA-IR, fasting plasma glucose (FPG) and 2-h post-load glucose (2hPG) load with CHD incidence among such patients. Methods A total of 2607 patients with T2D were enrolled in a community-dwelling cohort and followed for an average of 7.2 years. Conventional CHD risk factors, FPG, 2hPG, fasting insulin levels and HOMA-IR index were measured at baseline. Cox regression hazard ratios (HRs) were used to assess CHD risk. Results A total of 299 ‘hard’ CHD events were registered (in 114 women and 185 men). Increasing levels of fasting insulinaemia were positively associated with CHD incidence. This correlation persisted after controlling for gender, body mass index, blood pressure, lipid profile, medication use and HbA1c [HR for each increase in quartile (fully adjusted model): 1.18 (95% CI: 1.06–1.32); P < 0.01]. 2hPG showed a non-linear association with incident CHD [HR of highest vs lowest quartile: 1.64 (95% CI: 1.03–2.61)]. Fasting glycaemia was not associated with CHD risk, whereas HOMA-IR had a direct and independent correlation with CHD risk [HR for each one-quartile increase: 1.19 (95% CI: 1.07–1.34); P < 0.01]. Conclusion Fasting insulin levels are positively associated with incidence of CHD in T2D. Furthermore, 2hPG appears to be a significant predictor of incident CHD independently of other risk factors, including HbA1c. These findings suggest that strategies targeting the reduction of insulinaemia and post-load glycaemia may be useful for preventing cardiovascular complications

The transition zones especially railroad bridge transitions are one the weakest track sections that need more maintenance in order to keep a good track performance. These locations are also commonly create noise and vibration pollution which is unpleasant specifically in urban parts of the city. A new product known as Resiliently Bound Ballast (RBB) is a new engineered material composed of Ballast, tire derived aggregate (TDA) and proprietary elastomeric epoxy binder which can be manufactured with different mixtures to meet various engineering properties. In order to study the workability of this material in railroad bridges, in this research a one dimensional (1D) two degree of freedom (2DOF) composite RBB-Ballast track on concrete deck bridge has been modeled with different RBB thicknesses from 0.01 in. (0.025 cm) to 23.99 in. (60.94 cm) and material damping of 2.5, 5 and 10 %. The range of properties for RBB are based upon values obtained from static and dynamic testing. The results show that the most peak amplitude reduction occurs between 2.5% to 5% damping, RBB has the ability to dissipate energy over a broader range of frequencies and as the damping increases, the RBB thickness becomes more effective in track dynamic performance.

Reduced-intensity conditioning (RIC) has offered many primary immunodeficiency disorder (PID) patients who are ineligible for myeloablative regimens a chance of cure. However, the beneficial role of RIC was questioned following reports suggesting higher chance of rejection and lower symptom resolution rate in mixed chimerism settings. Forty-five children affected by PIDs with a median age of 21 months underwent allogeneic hematopoietic stem cell transplantation in our institute from 2007 to 2013. All patients received an identical RIC regimen. Forty-one patients had successful primary engraftment (91%). Of the successful engraftments, 80% (n=33) had stable full donor chimerism at last contact. Overall, eleven transplant-related mortalities were reported including five patients due to sepsis, three children due to grade IV acute GvHD, two due to chronic GvHD and one patient due to sepsis after primary graft failure. The median post-transplantation follow-up of deceased patients was 55 days. Five-year overall survival and disease-free survival was 75.6% and 68.89%, respectively. All surviving patients with successful engraftment became disease free, regardless of having full or mixed chimerism. Our study suggests that RIC regimen provides satisfactory rates of successful engraftment and full chimerism. Furthermore, patients with mixed chimerism were stable in long-term follow-up and this chimerism status offered the potential to resolve symptoms of immunodeficiency.

In recent years there has been an increase in the knowledge of, and need for, non-invasive monitoring of ballast in order to identify the problematic sections of track and decrease the maintenance cost. Various technologies such as Ground Penetrating Radar (GPR) are becoming accepted for investigating the condition of ballast. However since these techniques were not originally developed for engineering applications, their applicability in ballast evaluations can be sometimes uncertain. Continued empirical studies and condition specific calibrations are needed to demonstrate repeatable and quantifiable results. In this study large-scale track models with trapezoidal section area were constructed at the University of Massachusetts to investigate the effects of breakdown fouling, and the effects of changing geotechnical properties on GPR traces. This paper presents the design and construction of large scale track models, and methods used for GPR data collection. GPR data are presented in this paper that demonstrate sensitivity to the track model properties and variables. In particular, the experiments are being used to evaluate changes in GPR data with changing geotechnical properties of the ballast such as density, water content, grain size distribution (GSD), and fouling percentage.

Diabetic neuropathy (DN) is the most common complication of diabetes mellitus (DM) and also the major cause of morbidity and mortality in diabetic patients. There have been recent speculations that circulating 25-hydroxyvitamin D (25(OH)-D) could be involved in DN development and progression. This study explored the association between serum 25(OH)-D and DN in diabetic subjects by performing strict matching of possible confounders. Overall, 33 diabetic subjects with DN and 29 controls matched in terms of age, sex, BMI, height and disease duration entered this study. Nerve conduction velocity (NCV) was performed to determine the existence and severity of large fiber neuropathy. 25(OH)-D had significantly lower value in DN group (21.2 ± 11.5 vs. 13.5 ± 5.1 ng/mL, P = 0.001). None of the other observed variables showed a significant association with existence and severity of DN. After adjustment for all studied variables, serum vitamin D had an independent and inverse association with both DN presence and severity, as each 1 ng/mL increase in serum 25(OH)-D was correlated with 2.2 and 3.4 % decrease in the presence and severity of NCV impairment, respectively. While adjusted for demographic variables, comorbidities and treatment of DM, our results imply that decreased levels of circulating 25(OH)-D may contribute to increased risk of large fiber neuropathy in type 2 diabetic subjects.

Background: Good knowledge, attitude and practice (KAP) of the physicians allow them to handle their patients in such a way that they prevent themselves from contracting, and their patients from spreading, the infection. However, the Iranian standardized KAP questionnaire of physicians about viral hepatitis is not available. So, we developed a standard questionnaire. Objectives: The purpose of this study was to provide a standard questionnaire as a basic tool for assessment of the present situation of the KAP of clinicians. It can also be used for evaluating educational programs and interventions on physicians in addition to any trends in their KAP about viral hepatitis. Patients and Methods: In order to design and standardize a 29-item self-administered questionnaire, we developed a cross sectional pilot study on 60 Iranian physicians. Ten experts in the field of liver diseases and/or designing the questionnaire answered questions about its validity. Cronbach's Alpha (on 60 physicians that participated in a congress) and factor analysis (on 370 persons; participants of two viral hepatitis congresses in Tehran and Zanjan and physicians of two university hospitals in Ahvaz) were used in the analysis. Results: Reliability was 0.7 according to Cronbach's Alpha score. Face validity was higher than 80%. Content validity of the whole parts of the questionnaire was 96.25% for clarity, 91.56% for relevancy, 96.25% for simplicity and 98.44% for consistency of each question with the questions' set. Factor analysis showed that 13 components account for 67.4% of the total variance. Conclusions: This study provided evidence that our questionnaire is a feasible, valid and reliable measure of physicians' KAP status in Iran. The factor analysis did not reveal a strong cluster structure. This questionnaire should be interpreted as a one-dimensional element by the sum of all items, rather than a multi-dimensional instrument.

Background and Aims Health care workers (HCWs) are at risk of contracting and spreading hepatitis B virus (HBV) and hepatitis C virus (HCV) to others. The aim of this study was to evaluate knowledge, attitudes and behavior of physicians concerning HBV and HCV. Methods A 29-item questionnaire (reliability coefficient = 0.7) was distributed at two national/regional congresses and two university hospitals in Iran. Five medical groups (dentists, general practitioners, paraclinicians, surgeons and internists) received 450 questionnaires in 2009, of which 369 questionnaires (82%) were filled out. Results Knowledge about routes of transmission of HBV and HCV, prevalence rate and seroconversion rates secondary to a needlestick injury was moderate to low. Concern about being infected with HBV and HCV was 69.4±2.1 and 76.3±2 (out of 100), respectively. Complete HBV vaccination was done on 88.1% of the participants. Sixty percent had checked their hepatitis B surface antibody (anti-HBs), and 83.8% were positive. Only 24% of the surgeons often used double gloves and 28% had reported a needlestick. There was no significant correlation between the different specialties and: concern about HBV and HCV; the underreporting of needlestick injuries; and correct knowledge of post-needlestick HBV infection. Conclusions Although our participants were afraid of acquiring HBV and HCV, knowledge about routes of transmission, prevalence, protection and post-exposure seroconversion rates was unsatisfactory. By making physicians aware of possible post-exposure prophylaxis, the underreporting of needlestick injuries could be eliminated. Continuous training about HBV and HCV transmission routes, seroconversion rates, protection, as well as hepatitis B vaccination and checking the anti-HBs level, is a matter of necessity.

Background Perhaps more than any other healthcare worker, it is the surgeons who are at an increased risk of exposure to hepatitis B (HB) virus, hepatitis C virus, and human immunodeficiency virus. The aim of this study was to evaluate surgeons' concerns regarding risk awareness and behavioral methods of protection against blood-borne pathogen transmission during surgery. Materials and methods A 31-item questionnaire with a reliability coefficient of 0.73 was used. Of 575 surgeons invited to participate from three universities and one national annual surgical society between May and July 2007, 430 (75%) returned completed forms. Results Concern about being infected with blood-borne diseases was more than 70 (from a total score of 100). Only 12.9% of surgeons always used double gloves. Complete vaccination against HB was done in about 76% of surgeons and only 56.8% had checked their HB surface antibody (anti-HBs) level. Older surgeons never used double gloves ( P = 0.001). Conclusion Iranian surgeons are not aware of the correct percentage of infected patients with and seroconversion rate of blood-borne diseases, do not use double gloves adequately, do not report their needlestick injuries, vaccinate against HB, and check anti-HBs after vaccination. Educational meetings, pamphlets, and facilities must be provided to health care workers, informing them of hazards, prevention, and postexposure prophylaxis to needlestick injuries, vaccination efficacy, and wearing double gloves.