Radiation accounts for a significant fraction of the human body and environment heat exchange and strongly impacts thermal comfort and safety. The direct radiative exchange between an individual and ...a source or sink can be quantified using the effective (
f
eff
) and projected radiation area factors (
f
p
). However, these factors have not been quantified for half of the population of the USA with an above-average body mass index (BMI). Here, we address this gap by developing thirty male and thirty female computational manikin models that cover the 1 to 99 percentile variation in height and BMI of adults in the USA. The radiative simulations reveal that the
f
eff
and the
f
p
angular distributions are nearly independent of gender, height, and BMI. Appreciable relative differences from the average models only emerge for manikins with BMI above 80th percentile. However, these differences only occur at low zenith angles and, in absolute terms, are small as compared to variations induced by, for example, the zenith angle increase. We also use the manikin set to evaluate whether the body shape impacts the quality of human representation with several levels of geometrical simplification. We find that the “box/peg” body representation, which is based on the hemispherical
f
p
average, is independent of the body shape. In turn, the
f
p
distributions averaged over the azimuth angle range, representing the rotationally symmetric humans, are only impacted to the same degree as for the anatomical manikins. We also show that the anatomical manikins can be closely approximated by the multi-cylinder and sphere representation, at least from a radiation perspective. The developed anatomical manikin set is freely available and can be used to compute how body shape impacts a variety of external heat transport processes.
Inhalation toxicity testing, which provides the basis for hazard labeling and risk management of chemicals with potential exposure to the respiratory tract, has traditionally been conducted using ...animals. Significant research efforts have been directed at the development of mechanistically based, non-animal testing approaches that hold promise to provide human-relevant data and an enhanced understanding of toxicity mechanisms. A September 2016 workshop, “Alternative Approaches for Acute Inhalation Toxicity Testing to Address Global Regulatory and Non-Regulatory Data Requirements”, explored current testing requirements and ongoing efforts to achieve global regulatory acceptance for non-animal testing approaches. The importance of using integrated approaches that combine existing data with in vitro and/or computational approaches to generate new data was discussed. Approaches were also proposed to develop a strategy for identifying and overcoming obstacles to replacing animal tests. Attendees noted the importance of dosimetry considerations and of understanding mechanisms of acute toxicity, which could be facilitated by the development of adverse outcome pathways. Recommendations were made to (1) develop a database of existing acute inhalation toxicity data; (2) prepare a state-of-the-science review of dosimetry determinants, mechanisms of toxicity, and existing approaches to assess acute inhalation toxicity; (3) identify and optimize in silico models; and (4) develop a decision tree/testing strategy, considering physicochemical properties and dosimetry, and conduct proof-of-concept testing. Working groups have been established to implement these recommendations.
•Drivers for acute inhalation toxicity testing were summarized.•The workshop explored non-animal testing approaches for acute inhalation toxicity.•Mechanistic determinants of dosimetry and toxic effects were reviewed.•Four key recommendations addressed data gathering and method development needs.
Four studies probe Ps’ sensitivity to absolute and relative savings. In three studies, Ps read scenarios forcing a tradeoff of saving more lives (230 vs. 225) vs. saving a larger proportion of a ...population (225
÷
230
=
75% vs. 230
÷
920
=
25%). Ps’ preferences were driven by both absolute and relative savings. Maximizing relative savings, called “proportion dominance” (PD), at the expense of absolute savings is non-normative, and most participants concur with this argument upon reflection (Studies 2 and 3). PD is related to individual differences, such that people scored as “rational” thinkers exhibited less PD than people scored as “experiential” thinkers (Studies 1 and 3). Finally, a fourth study extends these results, finding proportion dominance in other domains using a different paradigm. These four studies demonstrate both the generality (across domains and paradigms) and the variability (inter- and intra-individual) of proportion dominance.
Decisions, both moral and mundane, about saving individuals or resources at risk are often influenced not only by numbers saved and lost, but also by proportions of groups saved and lost. Consider ...choosing between a program that saves 60 of 240 lives at risk and one that saves 50 of 100. The first option maximizes absolute number saved; the second, proportion saved. In two studies, we show that the influence of proportions on such decisions depends on how items at risk are mentally represented. In particular, we show that proportions have greater influence on people's decisions to the extent that the items at risk are construed as forming groups, as opposed to distinct individuals. Construal was manipulated by means of animated displays in which resources at risk moved either independently (promoting individual construal) or jointly (promoting group construal). Results support the hypothesis that (a) decision makers form mental representations which vary in the degree to which resources at risk are construed as groups versus individuals and (b) construal of resources as groups promotes the influence of proportions on decisions and moral judgments.
Predicting human thermal comfort and safety requires quantitative knowledge of the convective heat transfer between the body and its surrounding. So far, convective heat transfer coefficient ...correlations have been based only upon measurements or simulations of the average body shape of an adult. To address this knowledge gap, here we quantify the impact of adult human body shape on forced convection. To do this, we generated fifty three-dimensional human body meshes covering 1st to 99th percentile variation in height and body mass index (BMI) of the USA adult population. We developed a coupled turbulent flow and convective heat transfer simulation and benchmarked it in the 0.5 to 2.5 m·s
−1
air speed range against prior literature. We computed the overall heat transfer coefficients, h
overall
, for the manikins for representative airflow with 2 m·s
−1
uniform speed and 5% turbulence intensity. We found that h
overall
varied only between 19.9 and 23.2 W·m
−2
K
−1
. Within this small range, the height of the manikins had negligible impact while an increase in the BMI led to a nearly linear decrease of the h
overall
. Evaluation of the local coefficients revealed that those also nearly linearly decreased with BMI, which correlated to an inversely proportional local area (i.e., cross-sectional dimension) increase. Since even the most considerable difference that exists between 1st and 99th percentile BMI manikins is less than 15% of h
overall
of the average manikin, it can be concluded that the impact of the human body shape on the convective heat transfer is minor.
Comments on an article by Arthur B. Markman et al. (see record 2018-15854-001). Markman provides a thought-provoking perspective on the relationships between lab and field research, using his own ...research program on regulatory fit as an instructive example. He discusses characteristics of typical lab and field studies, identifies some examples of productive relationships, and analyzes the failure to communicate between lab and field researchers, focusing on the relationship between academic cognitive psychology research programs and naturalistic decision making programs. He also provides useful advice about how to facilitate interactions between researchers of each type. Markman “types” NDM studies as high in external validity and low in internal validity and implies that much of laboratorybased judgment and decision-making research is low in external validity but high in internal validity. We think taking a broader view of research that engages with the field may lead to different conclusions about the nature and inevitability of tradeoffs between lab and field. (PsycInfo Database Record (c) 2022 APA, all rights reserved)
There is great interest in assessing the in vivo toxicity of chemicals using nonanimal alternatives. However, acute mammalian toxicity is not adequately predicted by current in silico or in vitro ...approaches. Mechanisms of acute toxicity are likely conserved across invertebrate, aquatic, and mammalian species, suggesting that dose-response concordance would be high and in vitro mechanistic data could predict responses in multiple species under conditions of similar bioavailability. We tested this hypothesis by comparing acute toxicity between rat, daphnia, and fish and by comparing their respective acute data to inhibition of mitochondria membrane potential (MMP) using U.S. Environmental Protection Agency ToxCast in vitro high-throughput screening data. Logarithmic scatter plots of acute toxicity data showed a clear relationship between fish, daphnia, and intravenous rat but not oral rat data. Similar plots versus MMP showed a well-delineated upper boundary for fish, daphnia, and intravenous data but were scattered without an upper boundary for rat oral data. Adjustments of acute oral rat toxicity values by simulating fractional absorption and CYP-based metabolism as well as removing compounds with hydrolyzable linkages or flagged as substrates for glucuronidation delineated an upper boundary for rat oral toxicity versus MMP. Mitochondrial inhibition at low concentrations predicted highly acutely toxic chemicals for fish and daphnia but not the rat where toxicity was often attenuated. This use of a single high-throughput screening assay to predict acute toxicity in multiple species represents a milestone and highlights the promise of such approaches but also the need for refined tools to address systemic bioavailability and the impact of limited absorption and first pass metabolism.
Why do consumers embrace some algorithms and find others objectionable? The moral relevance of the domain in which an algorithm operates plays a role. The authors find that consumers believe that ...algorithms are more likely to use maximization (i.e., attempting to maximize some measured outcome) as a decision‐making strategy than human decision makers (Study 1). Consumers find this consequentialist decision strategy to be objectionable in morally relevant tradeoffs and disapprove of algorithms making morally relevant tradeoffs as a result (Studies 2, 3a, & 3b). Consumers also object to human employees making morally relevant tradeoffs when they are trained to make decisions by maximizing outcomes, consistent with the notion that their objections to algorithmic decision makers stem from concerns about maximization (Study 4). The results provide insight into why consumers object to some consumer relevant algorithms while adopting others.
Is morally motivated decision making different from other kinds of decision making? There is evidence that when people have sacred or protected values (PVs), they reject trade-offs for secular values ...(e.g., "You can't put a price on a human life") and tend to employ deontological rather than consequentialist decision principles. People motivated by PVs appear to show quantity insensitivity. That is, in trade-off situations, they are less sensitive to the consequences of their choices than are people without PVs. The current study examined the relation between PVs and quantity insensitivity using two methods of preference assessment: In one design, previous results were replicated; in a second, PVs were related to increased quantity sensitivity. These and other findings call into question important presumed properties of PVs, suggesting that how PVs affect willingness to make trade-offs depends on where attention is focused, a factor that varies substantially across contexts.
The treatment of children with embryonal brain tumors (EBT) includes craniospinal irradiation (CSI). There are limited data regarding the effect of CSI on pulmonary function.
Protocol SJMB03 enrolled ...patients 3 to 21 years of age with EBT. Pulmonary function tests (PFTs) (forced expiratory volume in 1 second FEV1 and forced vital capacity FVC by spirometry, total lung capacity TLC by nitrogen washout or plethysmography, and diffusing capacity of the lung for carbon monoxide corrected for hemoglobin DLCO(corr)) were obtained. Differences between PFTs obtained immediately after the completion of CSI and 24 or 60 months after the completion of treatment (ACT) were compared using exact Wilcoxon signed-rank tests and repeated-measures models.
Between June 24, 2003, and March 1, 2010, 303 eligible patients (spine dose: ≤ 2345 cGy, 201; >2345 cGy, 102; proton beam, 20) were enrolled, 260 of whom had at least 1 PFT. The median age at diagnosis was 8.9 years (range, 3.1-20.4 years). The median thoracic spinal radiation dose was 23.4 Gy (interquartile range IQR, 23.4-36.0 Gy). The median cyclophosphamide dose was 16.0 g/m(2) (IQR, 15.7-16.0 g/m(2)). At 24 and 60 months ACT, DLCO(corr) was <75% predicted in 23% (27/118) and 25% (21/84) of patients, FEV1 was <80% predicted in 20% (34/170) and 29% (32/109) of patients, FVC was <80% predicted in 27% (46/172) and 28% (30/108) of patients, and TLC was <75% predicted in 9% (13/138) and 11% (10/92) of patients. DLCO(corr) was significantly decreased 24 months ACT (median difference MD in % predicted, 3.00%; P = .028) and 60 months ACT (MD in % predicted, 6.00%; P = .033) compared with the end of radiation therapy. These significant decreases in DLCO(corr) were also observed in repeated-measures models (P = .011 and P = .032 at 24 and 60 months ACT, respectively).
A significant minority of EBT survivors experience PFT deficits after CSI. Continued monitoring of this cohort is planned.
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