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In recent years, the volume of parcel shipments has increased significantly because of the rise in popularity of online shopping. This article focuses on the last mile segment of the parcel shipment, especially on the vibration behavior of the packages and van platform during transportation and the laboratory simulation of transportation vibration circumstances. The goal of this study is to measure in the field the vibration levels of small, stacked parcels and compare the results with measured vibration levels from the same measuring setup in the laboratory using ASTM D7386-16, Standard Practice for Performance Testing of Packages for Single Parcel Delivery Systems, vibration test method. For the measurements, three-layers of stacked small boxes with data recorder were set up into a delivery van to observe the vibration levels for the boxes inside and on the platform of the van, along different road conditions. The power spectral density spectra and overall Grms values of vibration intensity were presented and compared in four sections of frequency range between 1-200 Hz. The results indicate that the proposed vibration simulation does not correlate well with typical field vibration levels of the van platform and stacked packages. Based on the results, the packaging testing process can be developed as a more realistic preshipment testing process to avoid under-testing or over-testing of small parcels, thereby eliminating unnecessary packaging costs or damages. [ABSTRACT FROM AUTHOR]

BackgroundThe method of estimating distance traveled by the pulse wave, used in the calculation of pulse wave velocity (PWV), is not standardized. Our objective was to assess whether different methods of distance measurement influenced the association of PWV to cardiovascular mortality in hemodialysis (HD) patients.MethodsNinety-eight chronic HD patients had their PWV measured using three methods for distance estimation; PWV1: suprasternal notch-to-femoral site minus suprasternal notch-to-carotid site, PWV2: carotid-to-femoral site, PWV3: carotid-to-femoral site minus suprasternal notch-to-carotid site. Carotid-to-femoral distance was used to approximate torso length. Patients were followed for a median of 30 months and the association of PWV and cardiovascular mortality was assessed using survival analysis before and after stratification for torso length.ResultsThe three methods resulted in significantly different PWV values. During follow-up 50 patients died, 32 of cardiovascular causes. In log-rank tests, only tertiles of PWV1 was significantly related to outcome (P values 0.017, 0.257, 0.137, for PWV1, PWV2, and PWV3, respectively). In adjusted Cox, proportional hazards regression only PWV1 was related to cardiovascular mortality. In stratified analysis, however, among patients with below median torso length all PWV values were related to outcome, whereas in patients with above median torso length none of the PWV methods resulted in significant relationship to outcome.ConclusionsPWV calculated using suprasternal notch-to-femoral distance minus suprasternal notch-to-carotid distance provides the strongest relationship to cardiovascular mortality. Longer torso weakens the predictive value of PWV, possibly due to more tortuosity of the aorta hence, more error introduced when using surface tape measurements.American Journal of Hypertension (2011). doi:10.1038/ajh.2010.220 [ABSTRACT FROM AUTHOR]

Over the past few years gamma-hydroxybutyrate (GHB) has generated widespread media interest as a possible 'date rape drug'. Our goal was to examine the extent to which GHB is associated with drug-facilitated sexual assaults. Literature was searched systematically and 11 studies, published between 1961 and June 30, 2009, were identified dealing specifically with the role of GHB in sexual assaults. GHB was detected in 0.2-4.4% of reported sexual assaults. The results demonstrate that a wide range of drugs may be present in cases of sexual assault, and many of them are much more frequent than GHB. Our results do not support the widespread labelling of GHB as a date rape drug as the prevalence of GHB is much lower than of other substances used in sexual assaults. On the other hand, however, the possible risk of GHB in this regard should not be neglected. Nevertheless, over-sensitive and sensation seeking media reports focusing on the association of sex crime and GHB might be counterproductive and misleading as they turn the attention away from other substances that are often used in sexual assaults. [ABSTRACT FROM AUTHOR]

In previous studies, different parameters of arterial stiffness were related to cardiovascular mortality in hemodialysis patients, but their relative prognostic value has not previously been evaluated in 1 cohort. Carotid-femoral pulse wave velocity (PWV), the carotid augmentation index, carotid pulse pressure (CPP) and carotid-brachial pulse pressure amplification (AMP) were measured in 98 patients before and after hemodialysis. Patients were followed for a median of 29 months (1–34) and the association of these parameters with cardiovascular mortality were assessed using log-rank tests and Cox proportional hazards regressions. During follow-up, 25 patients died of cardiovascular causes. Increasing pre- and postdialysis PWV tertiles and decreasing predialysis AMP tertiles were significantly related to cardiovascular mortality (p = 0.012 and 0.011 for PWV, respectively; < 0.001 for AMP). Neither the carotid augmentation index nor carotid pulse pressure were related to cardiovascular mortality. The adjusted hazard ratios for 1 m/s higher pre- and postdialysis PWV were 1.24 (1.07–1.44) and 1.17 (1.06–1.28), respectively. The hazard ratio for 10% lower predialysis AMP was 1.41 (1.03–1.92). When included in the same model, both predialysis PWV and AMP remained significantly associated with cardiovascular mortality. Among different stiffness parameters, PWV is consistently related to cardiovascular mortality, irrespective of the timing of measurement. Predialysis AMP seems to provide additional prognostic information. Copyright © 2009 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

The goal of this review was to examine the current literature in the topic of problematic alcohol use, with a special focus on the epidemiological, etiological, and psychological factors to predict problem drinking in college students. We present the terminology of binge drinking used in international studies, because the diversity of definitions, units and labels tend to make international comparisons more difficult. We review the epidemiology and also short- and long-term risk factors linked to binge drinking. The biological and genetic background of alcohol use and related neurophysiologic studies are also addressed. In the last section we summarize the psychological characteristics of binge drinking besides highlighting the most recent direction of studies in the field of alcohol research, which emphasizes the role of expectations and motivation.