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Leveraging Epidemiology to Improve Risk Assessment.
The field of environmental public health is at an important crossroad. Our current biomonitoring efforts document widespread exposure to a host of chemicals for which toxicity information is lacking. At the same time, advances in the fields of genomics, proteomics, metabolomics, genetics and epigenetics are yielding volumes of data at a rapid pace. Our ability to detect chemicals in biological and environmental media has far outpaced our ability to interpret their health relevance, and as a result, the environmental risk paradigm, in its current state, is antiquated and ill-equipped to make the best use of these new data. In light of new scientific developments and the pressing need to characterize the public health burdens of chemicals, it is imperative to reinvigorate the use of environmental epidemiology in chemical risk assessment. Two case studies of chemical assessments from the Environmental Protection Agency Integrated Risk Information System database are presented to illustrate opportunities where epidemiologic data could have been used in place of experimental animal data in dose-response assessment, or where different approaches, techniques, or studies could have been employed to better utilize existing epidemiologic evidence. Based on the case studies and what can be learned from recent scientific advances and improved approaches to utilizing human data for dose-response estimation, recommendations are provided for the disciplines of epidemiology and risk assessment for enhancing the role of epidemiologic data in hazard identification and dose-response assessment
Evolution of Mass Outflow in Protostars
We have surveyed 84 Class 0, Class I, and flat-spectrum protostars in
mid-infrared [Si II], [Fe II] and [S I] line emission, and 11 of these in
far-infrared [O I] emission. We use the results to derive their mass outflow
rates. Thereby we observe a strong correlation of mass outflow rates with
bolometric luminosity, and with the inferred mass accretion rates of the
central objects, which continues through the Class 0 range the trend observed
in Class II young stellar objects. Along this trend from large to small
mass-flow rates, the different classes of young stellar objects lie in the
sequence Class 0 -- Class I/flat-spectrum -- Class II, indicating that the
trend is an evolutionary sequence in which mass outflow and accretion rates
decrease together with increasing age, while maintaining rough proportionality.
The survey results include two which are key tests of magnetocentrifugal
outflow-acceleration mechanisms: the distribution of the outflow/accretion
branching ratio b, and limits on the distribution of outflow speeds. Neither
rule out any of the three leading outflow-acceleration,
angular-momentum-ejection mechanisms, but they provide some evidence that disk
winds and accretion-powered stellar winds (APSWs) operate in many protostars.
An upper edge observed in the branching-ratio distribution is consistent with
the upper bound of b = 0.6 found in models of APSWs, and a large fraction
(0.31) of the sample have branching ratio sufficiently small that only disk
winds, launched on scales as large as several AU, have been demonstrated to
account for them.Comment: Version submitted to ApJ: 36 pages, 3 tables, 8 figure
Workplace bullying and employee outcomes: a moderated mediated model
This paper investigates the relationship between workplace bullying and employee outcomes in a healthcare setting. Drawing on HR process theory, we investigate the mediating role of the perceived effectiveness of implementation of anti-bullying practices on employee outcomes and whether targeted line manager training was a moderator of that relationship. Our multi-level analysis (utilising responses from 1,507 employees within forty-seven hospitals with matched HR Director interviews), finds that the relationship between workplace bullying and employee outcomes is partially mediated by employees’ perceived effective implementation of intended anti-bully practices. The mediated relationship is moderated by targeted line manager training in anti-bullying practices. The mediated moderation model illustrates that it is effective implementation of anti-bullying practices enhanced by targeted training that is required to reduce bullying probabilities and their associated negative employee outcomes. The paper contributes to resource based view (RBV) of the firm, HR process and human capital theories. The implications for future research and practice are discussed
Constraining the Chemical Signatures and the Outburst Mechanism of the Class 0 Protostar HOPS 383
We present observations toward HOPS 383, the first known outbursting Class 0
protostar located within the Orion molecular cloud using ALMA, VLA, and SMA.
The SMA observations reveal envelope scale continuum and molecular line
emission surrounding HOPS 383 at 0.85 mm, 1.1 mm, and 1.3 mm. The images show
that HCO and HCO peaks on or near the continuum, while
NH is reduced at the same position. This reflects the underlying
chemistry where CO evaporating close to the protostar destroys NH while
forming HCO. We also observe the molecular outflow traced by CO () and (). A disk is resolved in the ALMA
0.87 mm dust continuum, orthogonal to the outflow direction, with an apparent
radius of 62 AU. Radiative transfer modeling of the continuum gives disk
masses of 0.02 M when fit to the ALMA visibilities. The models
including VLA 8 mm data indicate that the disk mass could be up to a factor of
10 larger due to lower dust opacity at longer wavelengths. The disk temperature
and surface density profiles from the modeling, and an assumed protostar mass
of 0.5 M suggest that the Toomre parameter before the
outburst, making gravitational instability a viable mechanism to explain
outbursts at an early age if the disk is sufficiently massive.Comment: Accepted by Ap
Chemical and physical variations of cannabis smoke from a variety of cannabis samples in New Zealand
Studies have compared the chemical properties of tobacco smoke to those of cannabis smoke,
with the objective of identifying the chemical attributes responsible for the mutagenicity and
carcinogenicity of cannabis smoke. Comparative studies have included small sample sizes and
produced conflicting results. The aim of this study was to assess the major chemical and
physical variations of cannabis smoke across a range of cannabis samples of different potencies
and origins, sourced from the illegal market in New Zealand. Twelve cannabis samples were
studied ranging from 1.0% to 13.4% delta-9-tetrahydrocannabinol (D9THC) content. A smoking
machine was used to smoke “joints” (cannabis cigarettes) and the chemical/physical properties
of the smoke assessed. The chemical constituents of the smoke extracts were analysed by gas
chromatography/mass spectrometry. A range of different chemical constituents (in addition to
D9THC) were identified and their concentrations estimated. Terpenoids were identified as the
major variable in cannabis smoke, showing a 40-fold range in total terpenoid content. Analysis
of the total particulate matter showed that significantly different levels of particulate matter
were produced between the different cannabis samples, ranging from 14.6 to 66.3 mg/g of
cannabis smoked. The D9THC delivery efficiency during smoking was also investigated and
produced consistent results showing a mean and median of 12.6% and 10.8%, respectively, of
the theoretically available D9THC (ranging from 7.2% to 28.0%)
Diagnostic Utility of the Impact of Event Scale-Revised in Two Samples of Survivors of War
The study aimed at examining the diagnostic utility of the Impact of Event Scale-Revised (IES-R) as a screening tool for post-traumatic stress disorder (PTSD) in survivors of war. The IES-R was completed by two independent samples that had survived the war in the Balkans: a sample of randomly selected people who had stayed in the area of former conflict (n = 3,313) and a sample of refugees to Western European countries (n = 854). PTSD was diagnosed using the MINI International Neuropsychiatric Interview. Prevalence of PTSD was 20.1% in the Balkan sample and 33.1% in the refugee sample. Results revealed that when considering a minimum value of specificity of 0.80, the optimally sensitive cut-off score for screening for PTSD in the Balkan sample was 34. In both the Balkan sample and the refugee sample, this cut-off score provided good values on sensitivity (0.86 and 0.89, respectively) and overall efficiency (0.81 and 0.79, respectively). Further, the kappa coefficients for sensitivity for the cut-off of 34 were 0.80 in both samples. Findings of this study support the clinical utility of the IES-R as a screening tool for PTSD in large-scale research studies and intervention studies if structured diagnostic interviews are regarded as too labor-intensive and too costly
Plate versus bulk trolley food service in a hospital: comparison of patients’ satisfaction
Objective
The aim of this research was to compare plate with bulk trolley food service in hospitals in terms of patient satisfaction. Key factors distinguishing satisfaction with each system would also be identified.
Methods
A consumer opinion card (n = 180), concentrating on the quality indicators of core foods, was used to measure patient satisfaction and compare two systems of delivery, plate and trolley. Binary logistic regression analysis was used to build a model that would predict food service style on the basis of the food attributes measured. Further investigation used multinomial logistic regression to predict opinion for the assessment of each food attribute within food service style.
Results
Results showed that the bulk trolley method of food distribution enables all foods to have a more acceptable texture, and for some foods (potato, P = 0.007; poached fish, P = 0.001; and minced beef, P ≤ 0.0005) temperature, and for other foods (broccoli, P ≤ 0.0005; carrots, P ≤ 0.0005; and poached fish, P = 0.001) flavor, than the plate system of delivery, where flavor is associated with bad opinion or dissatisfaction. A model was built indicating patient satisfaction with the two service systems.
Conclusion
This research confirms that patient satisfaction is enhanced by choice at the point of consumption (trolley system); however, portion size was not the controlling dimension. Temperature and texture were the most important attributes that measure patient satisfaction with food, thus defining the focus for hospital food service managers. To date, a model predicting patient satisfaction with the quality of food as served has not been proposed, and as such this work adds to the body of knowledge in this field. This report brings new information about the service style of dishes for improving the quality of food and thus enhancing patient satisfaction
Temporal discounting in major depressive disorder.
BACKGROUND: Major depressive disorder (MDD) is associated with abnormalities in financial reward processing. Previous research suggests that patients with MDD show reduced sensitivity to frequency of financial rewards. However, there is a lack of conclusive evidence from studies investigating the evaluation of financial rewards over time, an important aspect of reward processing that influences the way people plan long-term investments. Beck's cognitive model posits that patients with MDD hold a negative view of the future that may influence the amount of resources patients are willing to invest into their future selves. METHOD: We administered a delay discounting task to 82 participants: 29 healthy controls, 29 unmedicated participants with fully remitted MDD (rMDD) and 24 participants with current MDD (11 on medication). RESULTS: Patients with current MDD, relative to remitted patients and healthy subjects, discounted large-sized future rewards at a significantly higher rate and were insensitive to changes in reward size from medium to large. There was a main effect of clinical group on discounting rates for large-sized rewards, and discounting rates for large-sized rewards correlated with severity of depressive symptoms, particularly hopelessness. CONCLUSIONS: Higher discounting of delayed rewards in MDD seems to be state dependent and may be a reflection of depressive symptoms, specifically hopelessness. Discounting distant rewards at a higher rate means that patients are more likely to choose immediate financial options. Such impairments related to long-term investment planning may be important for understanding value-based decision making in MDD, and contribute to ongoing functional impairment
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