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This work presents a generalization of the Kraynik-Reinelt (KR) boundary conditions for nonequilibrium molecular dynamics simulations. In the simulation of steady, homogeneous flows with periodic boundary conditions, the simulation box deforms with the flow, and it is possible for image particles to become arbitrarily close, causing a breakdown in the simulation. The KR boundary conditions avoid this problem for planar elongational flow and general planar mixed flow [T. A. Hunt, S. Bernardi, and B. D. Todd, J. Chem. Phys. 133, 154116 (2010)] through careful choice of the initial simulation box and by periodically remapping the simulation box in a way that conserves image locations. In this work, the ideas are extended to a large class of three-dimensional flows by using multiple remappings for the simulation box. The simulation box geometry is no longer timeperiodic (which was shown to be impossible for uniaxial and biaxial stretching flows in the original work by Kraynik and Reinelt [Int. J. Multiphase Flow 18, 1045 (1992)]. The presented algorithm applies to all flows with nondefective flow matrices, and in particular, to uniaxial and biaxial flows. [ABSTRACT FROM AUTHOR]

We present early-time (t < +50 d) observations of SN 2019muj (=ASASSN-19tr), one of the best-observed members of the peculiar SN Iax class. Ultraviolet and optical photometric and optical and near-infrared spectroscopic follow-up started from ∼5 d before maximum light [ t max(B) on |$58707.8$| MJD] and covers the photospheric phase. The early observations allow us to estimate the physical properties of the ejecta and characterize the possible divergence from a uniform chemical abundance structure. The estimated bolometric light-curve peaks at 1.05 × 1042 erg s−1 and indicates that only 0.031 M⊙ of 56Ni was produced, making SN 2019muj a moderate luminosity object in the Iax class with peak absolute magnitude of |$M_\rm {V} = -16.4$| mag. The estimated date of explosion is t 0 = |$58698.2$| MJD and implies a short rise time of t rise = 9.6 d in B band. We fit of the spectroscopic data by synthetic spectra, calculated via the radiative transfer code tardis. Adopting the partially stratified abundance template based on brighter SNe Iax provides a good match with SN 2019muj. However, without earlier spectra, the need for stratification cannot be stated in most of the elements, except carbon, which is allowed to appear in the outer layers only. SN 2019muj provides a unique opportunity to link extremely low-luminosity SNe Iax to well-studied, brighter SNe Iax. [ABSTRACT FROM AUTHOR]

We present panchromatic observations and modeling of the Calcium-rich supernova (SN) 2019ehk in the star-forming galaxy M100 (d ≈ 16.2 Mpc) starting 10 hr after explosion and continuing for ∼300 days. SN 2019ehk shows a double-peaked optical light curve peaking at t = 3 and 15 days. The first peak is coincident with luminous, rapidly decaying Swift-XRT–discovered X-ray emission (at 3 days; Lx ∝ t−3), and a Shane/Kast spectral detection of narrow Hα and He ii emission lines (v ≈ 500) originating from pre-existent circumstellar material (CSM). We attribute this phenomenology to radiation from shock interaction with extended, dense material surrounding the progenitor star at r < 1015 cm and the resulting cooling emission. We calculate a total CSM mass of ∼7 × 10−3 (MHe/MH ≈6) with particle density n ≈ 109 cm−3. Radio observations indicate a significantly lower density n < 104 cm−3 at larger radii r > (0.1–1) × 1017 cm. The photometric and spectroscopic properties during the second light-curve peak are consistent with those of Ca-rich transients (rise-time of tr = 13.4 ± 0.210 days and a peak B-band magnitude of MB = −15.1 ± 0.200 mag). We find that SN 2019ehk synthesized (3.1 ± 0.11) × 10−2 of and ejected Mej = (0.72 ± 0.040) total with a kinetic energy Ek = (1.8 ± 0.10) × 1050 erg. Finally, deep HST pre-explosion imaging at the SN site constrains the parameter space of viable stellar progenitors to massive stars in the lowest mass bin (∼10) in binaries that lost most of their He envelope or white dwarfs (WDs). The explosion and environment properties of SN 2019ehk further restrict the potential WD progenitor systems to low-mass hybrid HeCO WD+CO WD binaries. [ABSTRACT FROM AUTHOR]

Several numerical schemes are proposed for the solution of Nonequilibrium Langevin Dynamics (NELD), and the strong rate of convergence for each scheme is analyzed. The schemes considered here employ specialised periodic boundary conditions that deform with the flow, namely Lees-Edwards and Kraynik-Reinelt boundary conditions and their generalisations. We show that care must be taken when implementing standard stochastic integration schemes with these boundary conditions in order to avoid a breakdown in the strong order of convergence. [ABSTRACT FROM AUTHOR]

We develop a rigorous error analysis for coarse-graining of defect-formation free energy. For a one-dimensional constrained atomistic system, we establish the thermodynamic limit of the defect-formation free energy and obtain explicitly the rate of convergence. We then construct a sequence of coarse-grained energies with the same rate but significantly reduced computational cost. We illustrate our analytical results through explicit computations for the case of harmonic potentials and through numerical simulations. [ABSTRACT FROM AUTHOR]

Background: Diabetic kidney disease (DKD) is the leading cause of end-stage renal disease in the Western world. Early and accurate identification of DKD offers the best chance of slowing the progression of kidney disease. An important method for evaluating risk of progressive DKD is abnormal albumin excretion rate (AER). Due to the high variability in AER, most guidelines recommend the use of more than or equal to two out of three AER measurements within a 3- to 6-month period to categorise AER. There are recognised limitations of using AER as a marker of DKD because one quarter of patients with type 2 diabetes may develop kidney disease without an increase in albuminuria and spontaneous regression of albuminuria occurs frequently. Nevertheless, it is important to investigate the long-term intra-individual variability of AER in participants with type 2 diabetes.Methods: Consecutive AER measurements (median 19 per subject) were performed in 497 participants with type 2 diabetes from 1999 to 2012 (mean follow-up 7.9 ± 3 years). Baseline clinical characteristics were collected to determine associations with AER variability. Participants were categorised as having normo-, micro- or macroalbuminuria according to their initial three AER measurements. Participants were then categorised into four patterns of AER trajectories: persistent, intermittent, progressing and regressing. Coefficients of variation were used to measure intra-individual AER variability.Results: The median coefficient of variation of AER was 53.3%, 76.0% and 67.0% for subjects with normo-, micro- or macroalbuminuria at baseline. The coefficient of variation of AER was 37.7%, 66% and 94.8% for subjects with persistent, intermittent and progressing normoalbuminuria; 43%, 70.6%, 86.1% and 82.3% for subjects with persistent, intermittent, progressing and regressing microalbuminuria; and 55.2%, 67% and 82.4% for subjects with persistent, intermittent and regressing macroalbuminuria, respectively.Conclusion: High long-term variability of AER suggests that two out of three AER measurements may not always be adequate for the optimal categorisation and prediction of AER. [ABSTRACT FROM AUTHOR]

Much work has gone into the construction of quasicontinuum energies that reduce the coupling error along the interface between atomistic and continuum regions. The largest consistency errors are typically pointwise O(1/ε) errors, where ε is the reference atomic spacing, and in some cases this has been reduced to pointwise O(1) errors. In this paper, we show that one cannot create a coupling method that has o(1)-consistency in the interface if the interface has a bounded number of degrees of freedom. We use this to give an upper bound on the order of accuracy in discrete w1, p-norms in one dimension. [ABSTRACT FROM AUTHOR]

We propose a derivation of a nonequilibrium Langevin dynamics for a large particle immersed in a background flow field. A single large particle is placed in an ideal gas heat bath composed of point particles that are distributed consistently with the background flow field and that interact with the large particle through elastic collisions. In the limit of small bath atom mass, the large particle dynamics converges in law to a stochastic dynamics. This derivation follows the ideas of [P. Calderoni, D. Dürr and S. Kusuoka, J. Stat. Phys. 55 (1989) 649–693. D. Dürr, S. Goldstein and J. Lebowitz, Z. Wahrscheinlichkeit 62 (1983) 427–448. D. Dürr, S. Goldstein and J.L. Lebowitz. Comm. Math. Phys. 78 (1981) 507–530.] and provides extensions to handle the nonzero background flow. The derived nonequilibrium Langevin dynamics is similar to the dynamics in [M. McPhie, P. Daivis, I. Snook, J. Ennis and D. Evans, Phys. A 299 (2001) 412–426]. Some numerical experiments illustrate the use of the obtained dynamic to simulate homogeneous liquid materials under shear flow. [ABSTRACT FROM AUTHOR]

We follow up on our previous work (Le Bris, C. & Legoll, F. (2007) Derivation of symplectic numerical schemes for highly oscillatory Hamiltonian systems. C. R. Acad. Sci., 344, 277–282 and Le Bris, C. & Legoll, F. (2010) Integrators for highly oscillatory Hamiltonian systems: an homogenization approach. Discrete Continuous Dyn. Syst. Ser. B, 13, 347–373) which presented a possible approach for deriving symplectic schemes for a certain class of highly oscillatory Hamiltonian systems. The approach considers the Hamilton–Jacobi form of the equations of motion, formally homogenizes it and infers an appropriate symplectic integrator for the original system. In Le Bris & Legoll (2007) and Le Bris & Legoll (2010), the case of a system exhibiting a single constant fast frequency was considered. The present work successfully extends the approach to systems that have either one varying fast frequency or several constant fast frequencies. Some related issues are also examined. [ABSTRACT FROM AUTHOR]

Investigates the relationship between individual differences in anxiety and eyewitness performance. Instructions designed to produce evaluative threat were given to anxious and nonanxious subjects at encoding and/or at retrieval. Performances of the subjects; Results.

Investigates the effect of self-reported vividness of visual imagery on the ability to discriminate between memories derived from two external sources of information. Testing of the recognition proficiency of high and low imagers; Role of vivid visual imagery as a variable underpinning confusions in eyewitness testimony.

Bryant (1996) outlined a recent Federal Court case where an applicant claimed to be suffering from posttraumatic stress disorder (PTSD) following exposure to atomic testing in Maralinga. In his paper, Bryant (1996) discusses the legal definition of a stressor, highlighting the ambiguity which remains in the DSM-IV definition of the stressor criterion (American Psychiatric Association, 1994). In this comment, our aim is not to question Bryant's argument concerning the ambiguity of the stressor criterion, but to question the view that there might be some way of objectifying the definition of a stressor in the diagnosis of PTSD, thereby standardising the diagnosis. Our perspective on the PTSD diagnosis is necessarily biased by our experience as clinicians and researchers in the field of war-related trauma. Although PTSD has been conceptualised as an anxiety reaction that follows in the wake of exposure to an extreme event, there may not be a discrete class of stressors that cause PTSD. In supporting this view, we argue that the etiology of PTSD is multidimensional. It follows that PTSD cannot be understood in terms of a cause-effect type relationship between the stressor and symptoms, as is required for the assessment of compensation/litigation claims in the courtroom setting. [ABSTRACT FROM AUTHOR]

Background: Self-reported physical health status of Australian Vietnam veterans was determined 20-25 years after the war and its relation to combat was investigated.Method: An epidemiological cohort study of a simple random sample of Army veterans posted to Vietnam between 1964 and 1972 was conducted with personal interviews using the Australian Bureau of Statistics Health Interview Survey questionnaire to compare veterans with the Australian population and a 21-item combat exposure index used to measure the relationship of combat to physical health.Results: Veterans reported greater health service usage and more recent health actions than population expectations. They also reported excess health problems in almost all recent illness disease categories except endocrine conditions and cardiovascular conditions; only 6 of 37 chronic disease groups were not elevated compared to the population. Adjustment for non-response changed estimates only slightly. Combat exposure was significantly related to reports of recent and chronic mental disorders, recent hernia and chronic ulcer, recent eczema and chronic rash, deafness, chronic infective and parasitic disease, chronic back disorders and symptoms, signs and ill-defined conditions.Conclusion: Combat exposure may have significantly increased reports of only some health problems. A general position to complain as a result of psychological conditions due to combat is not consistent with the lack of relationship between combat and reports of physical conditions. [ABSTRACT FROM AUTHOR]

Background Self-reported psychiatric status of Australian Vietnam war veterans was determined 20–25 years after the war and its relation to combat was investigated. Method A simple random sample of Australian Army Vietnam veterans was interviewed nationally using standardized interviews and self-completion tests to assess the prevalence of lifetime and current psychiatric illness and its relationship to combat. Army records were used to extract data on the cohort for use in regression-based adjustment for non-response. Results The conditions mainly affecting the Australian veterans were alcohol abuse or dependence, post-traumatic stress disorder, somatoform pain disorder and social and simple phobias. This profile is different from American studies of Vietnam veterans. All lifetime and 6-month recent disorders except depressive illness, melancholia, pathological gambling and somatization disorder were significantly related to combat exposure but not with posting to a combat unit. Less than half of the current one-month diagnoses were related to combat, possibly because of low power conferred by the relative rarity of these conditions. Conclusions The results confirm a range of psychological problems in former warriors may linger 20 or more years from their war exposure and may be directly affected by exposure to war trauma. [ABSTRACT FROM PUBLISHER]

Background: The Australian Vietnam Veterans Health Study was set up to examine the post-war health of former soldiers 20 or more years after service and to examine the relation of combat exposure to physical and mental health.Method: A prospective cohort study of a simple random sample of 1000 male Australian Army Vietnam veterans used information gathered from Army records, from personnel interview and questionnaires. Military records were used to examine response bias by determining the differences between 641 interviewed veterans, 50 known deceased veterans and 309 non-respondents (including 48 refusers and 213 non-traceable).Results: Differences were evident between respondents and non-respondents, with logistic regression modelling pointing to pre-enlistment employment, antisocial behaviour, intelligence and post-Vietnam AWOL (absent without leave) as the most important discriminants with non-respondents performing worse. Compared to respondents, deceased left school earlier, had higher rank in Vietnam and at discharge, had a higher overall number of charges but not a higher rate overall, and were less likely to have gone AWOL. Deceased also received more casualty reports than respondents and non-respondents, were better behaved during service, and were better emotionally adjusted than non-respondents. Respondents compared with the Australian population had equivalent or better current socioeconomic status.Conclusion: There seems little bias due to non-response, but deceased tend to come from and older cohort than in the other two groups. [ABSTRACT FROM AUTHOR]

Objective: The aims of this paper are to determine the risk factors for combat-related posttraumatic stress disorder (PTSD) and to examine the relative contribution of pre-military factors, pre-trauma psychiatric diagnoses, military factors such as combat posting, and combat and casualty stress exposure. Method: An epidemiological cohort study using standardised psychiatric, social and health interviews was undertaken with a national random sample of male Australian Army Vietnam veterans. Multivariate logistic regression was used to examine the relative contribution of factors derived from interview and from military records in four categories: pre-enlistment circumstances including home life, education, major life stress; pre-Vietnam psychiatric diagnoses; military experiences before and during Vietnam; and combat and stress experiences. Results: Of the 128 data items examined, significant associations were found for 39, in addition to combat stress. Pre-enlistment items accounted for about 3% of the deviance towards PTSD diagnosis, pre-enlistment psychiatric diagnosis about 13%, military variables about 7% and combat stress about 18%; all factors together accounted for 42%. Conclusions: The results confirm that pre-military and military variables make only a small but significant contribution to PTSD either alone or after controlling for combat stress; that psychiatric diagnoses of depression, dysthymia and agoraphobia make strong contributions to PTSD; but that combat stress makes the largest contribution even after controlling for the effects of other variables. Psychiatric diagnoses and combat stress appear to be independent in their effects on PTSD. [ABSTRACT FROM AUTHOR]

Examines the impact of combat-related posttraumatic stress disorder (PTSD) on Australian Vietnam veterans. Onset of PTSD and the comorbid diagnoses; Relationship of combat to comorbidity after controlling for PTSD; Use of risk factor analysis in differentiating men with lifetime PTSD and with no PTSD.

The article discusses the latest trends in the packaging industry in Europe as of July 2012. According to the author, the packaging industry has also been affected by the global economic crisis. It notes that packaging buyers have become smarter buyers and already looking for cost reductions without effecting the product quality. There is also a call for performance packaging that has the capacity to withstand extreme environmental conditions like shock, vibration and humidity.