446 research outputs found
Contributing Causes of Injury or Death in Grain Entrapment, Engulfment, and Extrication
No full textObjectives: Grain entrapments and engulfments are one of most common hazards associated with grain storage facilities, with over 1,140 such entrapments/engulfments documented since the 1970s. The objective of the study was to determine the factors that contribute to injury or death in grain entrapment, engulfment, and extrication cases. Methods: A literature review, including data contained in the Purdue Agricultural Confined Spaces Incident Database (PACSID), was conducted to determine the conditions that the body experiences during an entrapment or engulfment in grains and during extrication efforts. Results: Based on the review, the conditions a human body faces during an entrapment, engulfment, or extraction can be split into two broad categories—environmental and physiological/psychological. The environmental factors depend on the grain’s properties, depth of entrapment or engulfment, position of the victim’s body, and characteristics of the storage unit, which include the grain’s lateral pressure, vertical pressure, and weight, as well as friction, oxygen availability and diffusion rate, and grain temperature. The physiological and psychological factors are related to the individual’s age and physical and psychological conditions, and manifest themselves in terms of oxygen consumption, asphyxiation (including aspiration, lack of oxygen, compression or splinting of the thorax), blood flow, and heart rate. Conclusion: Of all the above factors, a review of fatality data contained in the PACSID indicate that aspiration, asphyxiation, grain weight, and lateral pressure are most likely the primary cause of death for most entrapment victims. Research gaps found by this study include an understanding of the impact of lateral pressure on lung expansion and oxygen availability and consumption rate, and the need for more case studies to accurately determine cause of death.This is the Submitted Manuscript of an article published by Taylor & Francis as Issa, Salah Fuad, William E. Field, Charles V. Schwab, Fadi S. Issa, and Eric A. Nauman. "Contributing Causes of Injury or Death in Grain Entrapment, Engulfment, and Extrication." Journal of Agromedicine 22, no. 2 (2017): 159-169. Available online: https://doi.org/10.1080/1059924X.2017.1283277. Posted with permission.</p
sj-pdf-1-jhs-10.1177_17531934231164959 - Supplemental material for Computerized adaptive testing for the patient evaluation measure (PEM) in patients undergoing cubital tunnel syndrome surgery
No full textSupplemental material, sj-pdf-1-jhs-10.1177_17531934231164959 for Computerized adaptive testing for the patient evaluation measure (PEM) in patients undergoing cubital tunnel syndrome surgery by Joris S. Teunissen, Steven E. R. Hovius, Dietmar J. O. Ulrich, Fadi Issa,
Jeremy N. Rodrigues, Conrad J. Harrison in Journal of Hand Surgery (European Volume)</p
Transgender as a Humanitarian Category
No full textAbstract In this article, the author foregrounds transgender as a useful category of analysis to shed light on the issue of gender variance and its articulations within the encounter between Syrian queer and gender-variant refugees and the humanitarian-asylum complex. Based on ethnographic fieldwork conducted with Syrian queer and gender-variant refugees in Istanbul in 2014 and 2015, this article contends that transgender as a term first circulates among the queer and gender-variant circles as a thinkable possibility primarily through its function as a humanitarian category, especially as propagated by the United Nations High Commissioner for Refugees (UNHCR). By highlighting this specific encounter, the author attempts to demonstrate, however, that rather than focusing on what the term does to the persons it interpellates, one must map out and document the ways the term is taken up and negotiated by the Syrian queer and gender-variant populations themselves, a method that could help ameliorate the negativity attached to transgender as a Western term and show that other systems of identification and histories of gender variance in the Syrian or Syrian diasporic contexts do not simply disappear or are subsumed by transgender, but are further complicated by it and continue to exist alongside it
Measurement of Left Ventricular Dimensions and Ejection Fraction in Neonates by Three-Dimensional Echocardiography: A Comparative Study Between Philips QLAB and TOMTEC Software-Are the Values Interchangeable?
No full textModulation of regulatory T cell function through specific molecular pathways in transplantation
No full textRegulatory T cells (Tregs) are crucial mediators of immune homeostasis that have shown immense promise as a cellular therapy for immune-mediated pathologies such as transplant rejection. Methods to optimise current Treg-based therapies are critical for its successful and widespread translation to the clinical setting. The aim of this study was to investigate the role of two molecular pathways for the modulation of Treg biology and function.
In the first part of this study, the role of the interleukin-33 (IL-33)/ST2 axis was interrogated in Tregs. This highly pleiotropic pathway has recently been demonstrated to have an important role in Treg biology. Here, it is shown that IL-33-expanded Tregs have enhanced in vivo suppressive function in a transplantation model. An in-depth characterization of IL-33-expanded Tregs is presented, providing a detailed quantitative transcriptomic and immunophenotypic analysis. Interestingly, this reveals IL-33-expanded Tregs to harbour a phenotypic signature of enhanced potential for graft-homing.
In the second part of the study, Treg plasticity and the environmental factors which govern their phenotype and function were examined, with a particular focus on the role of hypoxia and the principal regulators of oxygen homeostasis, the HIF/PHD pathway, in modulating Treg biology. Using an array of HIF/PHD2 transgenic mouse models, the study demonstrates that silencing of the critical prolyl hydroxylase domain-containing enzyme, Phd2, induces an autoimmune-like phenotype in mice. This is driven by upregulated HIF-2a signalling, in which the suppressive function of Treg populations is significantly impaired with loss of ability to control graft rejection. Additionally, evidence is presented to demonstrate that HIF-2a may be inhibited to enhance suppressive function of both mouse and human Tregs. These findings are replicated, at least in part, in mice subjected to chronic hypoxic.
While significant progress has been made to unlock the therapeutic potential of Tregs, there remains a great deal more to be learned regarding their behaviour and function for their effective and safe implementation within the clinic. The findings presented in this thesis uncover methods for the molecular manipulation of Tregs to help exploit their versatility for therapeutic use
Social Regulation of the Escape and Swim Motor Circuits in Dopamine Receptor Type 1 Mutant Zebrafish (Danio rerio)
No full textDominance hierarchies are an evolutionary mechanism to ensure the stability of animal groups by enabling the division of resources like food and mates according to social rank. Once dominance is established, the behavior pattern of individual group members shifts according to their social rank. We are motivated to better understand the neural bases of social behavior and how social activity influence nervous system function particularly the role of neuromodulators in regulating spinal motor circuits. Using zebrafish as a model organism, we tested the importance of the dopamine type 1 receptor (DRD1) in regulating social activity and spinal motor circuits in socially dominant and submissive fish by genetically knocking the DRD1 receptor.
Our motivation stems out of the fact that in many animal species dopamine plays an important role in regulating aggression, motivation and spinal motor activity. However, it remains poorly understood how social factors can influence dopaminergic signaling and its impact on motor function. We focused out attention on two easily quantifiable behaviors: the startle escape response and swimming behaviors.
In wildtype zebrafish, we found that subordinate animals display an elevated startle response sensitivity and reduced swimming activity compared to dominant animals. However, preliminary results show that although the DRD1 KO animals display similar status-dependent behavior patterns compared to wildtype pairs, these differences are less distinct. DRD1 KO subordinates continue to display heightened escape response sensitivity and reduced swimming activity compared to dominants, but those differences are less discernable. We aim to verify these results with a larger sample size. If confirmed, our results would suggest that the DRD1 receptor potentially plays an important role in regulating motor activity in a socially status-dependent manner
Characterization of Social Status-Dependent Neuromodulation in Zebrafish (Danio rerio)
No full textIn zebrafish (Danio rerio), social interactions between adult males consist of a series of aggressive encounters that ultimately lead to the formation of stable hierarchies of either socially dominant or subordinate animals. Although it has been shown that social status leads to neurophysiological changes in brain structure and function, our understanding of the underlying mechanisms that control behavioral function remains limited. We show that socially dominant animals display increased swimming activity. Conversely, social Subordinates display decreased swimming activity, but an enhanced sensitivity of the C-start escape circuit. We also show that whole brain expression of dopamine transporter (DAT) was significantly up-regulated in Dominants compared to Subordinates. In addition, Dopamine 1 receptor (D1R) expression was down-regulated in Subordinates compared to Dominants, suggesting that there is a social-status dependent regulation of the dopaminergic (DA) system. Finally, we show that visual cues play an important role in regulating zebrafish dominance relationships and the prioritization of different motor outputs by using a zebrafish line lacking pigmentation. Taken together, our results reveal that neuromodulation by DA signaling and visual information provides a mechanism for the nervous system to adapt to changes in social conditions by permitting the animal to prioritize a socially appropriate behavioral response
The Effect of Visual Queues on Social Status Formation and Mauthner Sensitivity in Zebrafish
No full textZebrafish of the TLN strain, a genetic variant of the Tüpfel Long-fin (TL) wild-type zebrafish that does not display the trademark striped scale pattern of wild-type zebrafish, but are instead pale, were tested through a series of behavioral observations to determine the role of visual queues in dominant/subordinate relationships. TLN zebrafish did not show significant differences in swimming behavior, escape response, or escape response latency, suggesting that it is possible that visual queues play a role in the formation of dominant/subordinate relationships, and in turn would affect the neurological sensitivity of the escape pathway when exposed to a threatening auditory stimulus
THE EFFECT OF SOCIAL EXPERIENCE ON BRAIN MORPHOLOGY IN ZEBRAFISH (DANIO RERIO)
No full textAdult male Zebrafish form stable dominance relationships that consist of dominant and subordinate animals. The long-term effects of social dominance on nervous system function remain poorly understood. Here, we investigated how social stress affects the morphological architecture of the hypothalamic dopaminergic nuclei implicated in social regulation and aggression. The dopaminergic system is a prime target of social factors given dopamine’s (DA) involvement in aggression, depression, stress and anxiety. We tested the hypothesis that social dominance induces morphological reorganization of the hypothalamic dopaminergic Posterior Tubercular rostral (PTar) and Caudal (PTac) nuclei. Both nuclei receive visual and olfactory social cues and relay the integrated information to spinal cord locomotor circuits to modulate locomotor activity. To test the effect of social dominance on the number of DA neurons we used the transgenic zebrafish line Tg(dat:EGFP) that expresses EGFP in all CNS dopaminergic neurons. Using confocal imaging of brain slices coupled with digital analysis, we compared the number of DA neurons in the PT nuclei between dominant and subordinate animals after two weeks of continuous social interactions; while group-housed (6 communally housed males) served as a control group. Our results show a significant increase in the number of DA neurons in dominants compared subordinate animals, while the number of DA neurons in communals was not statistically significant from neither dominants nor subordinates. Our results demonstrate that social dominance induces morphological reconfiguration of the hypothalamic DA system in a social status-dependent manner, and likely to have broader implications on other vertebrate social species
THE EFFECT OF SOCIAL EXPERIENCE ON THE SYNERGISTIC NEUROMODULATION OF MOTOR CIRCUITS
No full textForming social groups is a critical adaptive strategy for the survival of many animal species, where conflict between members can result in dominance relationships. Dominance relationships are often formed through aggressive interactions and influence the cognitive and physiological properties of individuals in a status-dependent manner. The aim of this dissertation is to discern how zebrafish utilize aggression and visual cues to reinforce a stable dominance relationship, and what effect stable dominance has on the neurobiological processes underlying motor behavior, with a focus on dopamine signaling. Dopamine has been implicated in aggression, social regulation, and modulation of motor circuits, making it a central point of study regarding the relationship between social dominance and motor behavior. Using behavioral, pharmacological, and genetic approaches, I have found that (1) in addition to physical aggression, zebrafish alter their stripe coloration intensity to reinforce dominance, (2) stable dominance alters dopamine signaling through decreased expression of the dopamine transporter and the dopamine receptor type-1b, (3) changes in dopamine signaling manifest in altered escape and swimming locomotor behavior, and (4) dopamine acts synergistically with other neurotransmitters to regulate status-dependent motor circuit activation. Results from this dissertation have provided evidence for how stable dominance impacts modulation of motor circuits, revealing how changes in relative excitability of multiple neuromodulatory inputs provide a mechanism for the nervous system to adapt to changes in social conditions and allow animals to select a socially appropriate behavioral response
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