3,963 research outputs found
Toward Self-Determination in the U.S. Territories: The Restorative Justice Implications of Rejecting the \u3cem\u3eInsular Cases\u3c/em\u3e
Conservatives and liberals alike are increasingly calling for condemnation of the Insular Casesâa series of U.S. Supreme Court cases from the early 1900s, in which the Court developed the doctrine of territorial incorporation to license the United Statesâ indefinite holding of overseas colonial possessions. In March 2021, members of the U.S. House of Representatives introduced House Resolution 279, which declares that the Insular Cases should be rejected as having no place in U.S. constitutional law. Moreover, in 2022, Justice Gorsuch called for the Supreme Court to squarely overrule the cases.
For many, rejecting the Insular Cases is a long-overdue reckoning for U.S. colonialism. Nonetheless, some representatives and scholars from the U.S. territories have raised concerns about potential implications for existing local laws in the territories. Many of these local laws protect Indigenous territorial peoples from further colonial harms. If the proposed bill or Supreme Courtâs overruling of the cases functioned to extend the U.S. Constitution in full to the territories, these laws may be found invalid under current constitutional jurisprudence.
This Article employs a contextual framework for Indigenous peoples to explore the nuanced restorative-justice implications of rejecting the Insular Cases. It emphasizes the varying perspectives of Indigenous peoples of the present-day U.S. territories, who would be most impacted by the measure. Finally, flowing from this restorative justice framework, this Article demands that any resolution to the Insular Cases forward the human rights principle of self-determination for Indigenous peoplesânot mere equality
Single-cell analysis of [Ca<sup>2+</sup>]i signalling in sub-fertile men:characteristics and relation to fertilization outcome
STUDY QUESTIONWhat are the characteristics of progesterone-induced (CatSper-mediated) single cell [Ca2+]i signals in spermatozoa from sub-fertile men and how do they relate to fertilizing ability?SUMMARY ANSWERSingle cell analysis of progesterone-induced (CatSper-mediated) [Ca2+]i showed that reduced progesterone-sensitivity is a common feature of sperm from sub-fertile patients and is correlated with fertilization rate.WHAT IS KNOWN ALREADYStimulation with progesterone is a widely used method for assessing [Ca2+]i mobilization by activation of CatSper in human spermatozoa. Although data are limited, sperm population studies have indicated an association of poor [Ca2+]i response to progesterone with reduced fertilization ability.STUDY DESIGN, SIZE, DURATIONThis was a cohort study using semen samples from 21 donors and 101 patients attending the assisted conception unit at Ninewells Hospital Dundee who were undergoing ART treatment. Patients were recruited from January 2016 to June 2017.PARTICIPANTS/MATERIALS, SETTING, METHODSSemen donors and patients were recruited in accordance with local ethics approval (13/ES/0091) from the East of Scotland Research Ethics Service (EoSRES) REC1. [Ca2+]i responses were examined by single cell imaging and motility parameters assessed by computer-assisted sperm analysis (CASA).MAIN RESULTS AND THE ROLE OF CHANCEFor analysis, patient samples were divided into three groups IVF(+ve) (successful fertilization; 62 samples), IVF-FF (failed fertilization; eight samples) and ICSI (21 samples). A further 10 IVF samples showed large, spontaneous [Ca2+]i oscillations and responses to progesterone could not be analysed. All patient samples loaded with the [Ca2+]i-indicator fluo4 responded to progesterone stimulation with a biphasic increase in fluorescence (transient followed by plateau) which resembled that seen in progesterone-stimulated donor samples. The mean normalized response (progesterone-induced increase in fluorescence normalized to resting level) was significantly smaller in IVF-FF and ICSI patient groups than in donors. All samples were further analysed by plotting, for each cell, the relationship between resting fluorescence intensity and the progesterone-induced fluorescence increment. In donor samples these plots overlaid closely and had a gradient of â 2 and plots for most IVF(+ve) samples closely resembled the donor distribution. However, in a subset (â 10%) of IVF(+ve) samples, 3/8 IVF-FF samples and one-third of ICSI samples the gradient of the plot was significantly lower, indicating that the response to progesterone of the cells in these samples was abnormally small. Examination of the relationship between gradient (regression coefficient of the plot) in IVF samples and fertilization rate showed a positive correlation. In IVF-FF and ICSI groups, the proportion of cells in which a response to progesterone could be detected was significantly lower than in donors and IVF (+ve) patients. Approximately 20% of cells in donor, IVF(+ve) and ICSI samples generated [Ca2+]i oscillations when challenged with progesterone but in IVF-FF samples only â 10% of cells generated oscillations and there was a significantly greater proportion of samples where no oscillations were observed. Levels of hyperactivated motility were lower in IVF(+ve) and IVF-FF groups compared to controls, IVF-FF also having lower levels than IVF(+ve).LIMITATIONS, REASONS FOR CAUTIONThis is an in vitro study and caution must be taken when extrapolating these results in vivo.WIDER IMPLICATIONS OF THE FINDINGSThis study reveals important details of impaired [Ca2+]i signalling in sperm from sub-fertile men that cannot be detected in population studies
Electron microscopic analysis of rotavirus assembly-replication intermediates
AbstractRotaviruses (RVs) replicate their segmented, double-stranded RNA genomes in tandem with early virion assembly. In this study, we sought to gain insight into the ultrastructure of RV assembly-replication intermediates (RIs) using transmission electron microscopy (EM). Specifically, we examined a replicase-competent, subcellular fraction that contains all known RV RIs. Three never-before-seen complexes were visualized in this fraction. Using in vitro reconstitution, we showed that ~15-nm doughnut-shaped proteins in strings were nonstructural protein 2 (NSP2) bound to viral RNA transcripts. Moreover, using immunoaffinity-capture EM, we revealed that ~20-nm pebble-shaped complexes contain the viral RNA polymerase (VP1) and RNA capping enzyme (VP3). Finally, using a gel purification method, we demonstrated that ~30â70-nm electron-dense, particle-shaped complexes represent replicase-competent core RIs, containing VP1, VP3, and NSP2 as well as capsid proteins VP2 and VP6. The results of this study raise new questions about the interactions among viral proteins and RNA during the concerted assemblyâreplicase process
Exploring Stress Mindset and Perceived Stress between College Student-Athletes and Non-Athletes
International Journal of Exercise Science 15(5): 1554-1562, 2022. Oneâs beliefs about the nature of stress (e.g., stress mindset) play a large role in the extent to which one experiences the detrimental or beneficial outcomes of stress. Stress mindset has been explored in college students, but there is limited research on stress mindsets in student-athletes. Sport can serve as a buffer to the negative impacts of stress for some student-athletes; however, pressures associated with sport participation increase stress in other student-athletes. Therefore, the purpose was to examine potential differences in stress mindset and perceived stress between non-athletes and college student-athletes. We hypothesized college student-athletes would report higher stress mindset scores but lower perceived stress scores. A total of 272 students (n = 87 student-athletes; n = 185 non-athletes) completed a demographic questionnaire, the Perceived Stress Scale, and the Stress Mindset Measure via an online survey. No significant differences were observed between student-athletesâ and non-athletesâ stress mindset scores; however, significant differences were observed between student-athletesâ and non-athletesâ perceived stress. Thus, student-athletes and non-athletes shared a similar view of stress, but student-athletes reported a lower level of perceived stress than non-athletes. While there appears to be no statistically significant differences in stress mindset between college non-athletes and student-athletes, both groups reported holding a stress-is-debilitating mindset. Implications for practitioners working with the college population are discussed
Use of a geometric rule or absolute vectors: Landmark use by Clarkâs nutcrackers (\u3ci\u3eNucifraga columbiana\u3c/i\u3e)
Clarkâs nutcrackers (Nucifraga columbiana) were trained to search for a hidden goal located in the center of a four-landmark array. Upon completion of training, the nutcrackers were presented with tests that expanded the landmark array in the east-west direction, north-south direction and in both directions simultaneously. Although the birds learned to search accurately at the center of the landmark array during training, this search pattern did not transfer to the expansion tests. The nutcrackers searched at locations defined by absolute distance and/or direction relationships with landmarks in the training array. These results contrast with those from experiments with nutcrackers in which an abstract geometric rule was learned. This difference appears due to differences in the experimental paradigms used during training
Barriers to and facilitators of implementing complex workplace dietary interventions: Process evaluation results of a cluster controlled trial
Background: Ambiguity exists regarding the effectiveness of workplace dietary interventions. Rigorous process evaluation is vital to understand this uncertainty. This study was conducted as part of the Food Choice at Work trial which assessed the comparative effectiveness of a workplace environmental dietary modification intervention and an educational intervention both alone and in combination versus a control workplace. Effectiveness was assessed in terms of employeesâ dietary intakes, nutrition knowledge and health status in four large manufacturing workplaces. The study aimed to examine barriers to and facilitators of implementing complex workplace interventions, from the perspectives of key workplace stakeholders and researchers involved in implementation. Methods: A detailed process evaluation monitored and evaluated intervention implementation. Interviews were conducted at baseline (27 interviews) and at 7â9 month follow-up (27 interviews) with a purposive sample of workplace stakeholders (managers and participating employees). Topic guides explored factors which facilitated or impeded implementation. Researchers involved in recruitment and data collection participated in focus groups at baseline and at 7â9 month follow-up to explore their perceptions of intervention implementation. Data were imported into NVivo software and analysed using a thematic framework approach. Results: Four major themes emerged; perceived benefits of participation, negotiation and flexibility of the implementation team, viability and intensity of interventions and workplace structures and cultures. The latter three themes either positively or negatively affected implementation, depending on context. The implementation team included managers involved in coordinating and delivering the interventions and the researchers who collected data and delivered intervention elements. Stakeholdersâ perceptions of the benefits of participating, which facilitated implementation, included managersâ desire to improve company image and employees seeking health improvements. Other facilitators included stakeholder buy-in, organisational support and stakeholder cohesiveness with regards to the level of support provided to the intervention. Anticipation of employee resistance towards menu changes, workplace restructuring and target-driven workplace cultures impeded intervention implementation. Conclusions: Contextual factors such as workplace structures and cultures need to be considered in the implementation of future workplace dietary interventions. Negotiation and flexibility of key workplace stakeholders plays an integral role in overcoming the barriers of workplace cultures, structures and resistance to change
Relation between physical activity and oxygen uptake efficiency in men with CVD
Purpose: The oxygen uptake efficiency slope (OUES) represents the rate of increase in VÌO2 in response to a given VÌE during incremental exercise, indicating how effectively oxygen is taken in by the lungs, transported and used in the periphery. OUES, calculated using only submaximal exercise data is identical to the OUES calculated over the entire duration of a cardiopulmonary exercise test (CEPT) , and both maximal and submaximal OUE are significantly related to cardiorespiratory fitness (CRF) measured as VÌO2peak. Currently, little research has been published on how physical activity (PA) assessed by accelerometers is related to submaximal and maximal OUES. The purpose of this study was to determine the relation light (LIPA), moderate (MIPA) and vigorous (VIPA) intensity physical activity and maximal and submaximal OUES in men with cardiovascular disease (CVD).
Methods: A total of 56 men (mean ( SD): age of 59.3 ± 9.2 yr., VÌO2 peak (L/min) 2.0 0.50, VÌO2 peak (mL/kg/min) 23.6 5.8, were recruited during an induction to a community-based exercise referral program following completion of phase 2 cardiac rehabilitation program. Participants underwent a graded exercise test on a cycle ergometer with breath by breath open circuit spirometry after which they wore a wrist worn accelerometer (Actigraph) for 7 d. Absolute and relative submaximal and maximal OUES were calculated by plotting VÌO2 in mL/min on the x axis, and the log transformed VE on the y axis (VÌO2 = a log 10 VE + b). Exercise data up to the ventilatory anaerobic threshold and maximal exercise were used to calculate submaximal and maximal OUE, respectively.
Results: Participants performed 584.49 73.87 min of daily LIPA, 145.45 60.85 min of MIPA and no daily min of VIPA. There was a significant relation between absolute submaximal OUES (r=0.386; p<0.01), submaximal OUES/Kg (r=0.296; p<0.05) and LIPA. There was a significant relation between maximal OUES (r=0.286; p<0.05), maximal OUES/Kg (r=0.279; p<0.05) and MIPA.
Conclusion: Submaximal and maximal OUE are related to levels of LIPA and MIPA, respectively. Submaximal OUES can potentially be used as an objective, effort independent test to estimate LIPA levels among men with CVD
Physical activity patterns and cardiorespiratory fitness in men with cardiovascular disease
Purpose: Cardiorespiratory fitness (CRF) is generally regarded as an objective and reproducible measure of recent habitual physical activity (PA). Considering that the majority of daily PA is performed at light intensity, it is likely that CRF benefits will be detected at submaximal rather than maximal exercise. The purpose of this study was to evaluate daily minutes of light (LIPA), moderate (MIPA) and vigorous (VIPA) intensity physical activity among men with cardiovascular disease (CVD), and to determine the relation between PA and submaximal (oxygen uptake efficiency slope (OUES)) and maximal (VÌO2 peak) indices of CRF.
Methods: A total 32 male participants (mean ( SD): age of 60.0 ± 8.7 yr, VÌO2 peak (L/min) 2.0 0.45, VÌO2 peak (mL/kg/min) 23.3 5.7, were recruited during an induction to a community based exercise referral program following completion of phase 2 cardiac rehabilitation. Participants underwent a graded exercise test on a cycle ergometer with breath by breath open circuit spirometry after which they wore a wrist worn accelerometer (Actigraph) for 7 d. Absolute and relative submaximal OUES were calculated by plotting VÌO2 in mL/min on the x axis, and the log transformed VE on the y axis (VÌO2 = a log 10 VE + b). Exercise data up to the ventilatory anaerobic threshold was included in the analysis.
Results: Participants performed 589.05 69.41 min of daily LIPA, 161.38 66.16 min of MIPA and no daily min of VIPA. There was no significant relation between peak VÌO2 and either LIPA or MIPA. There was a significant correlation between submaximal OUES (r=0.44; p<0.01) and LIPA. The relation between submaximal OUES/kg and LIPA min almost reached statistical significance (r=0.33; p<0.07). There was no significant relation between MIPA and OUES or OUES/kg.
Conclusion: Men with CVD spend the majority (78%) of their day performing LIPA. OUES, a submaximal measure of CRF was related LIPA whereas no relation was found between VÌO2 peak and LIPA
Submaximal oxygen uptake efficiency slope as a predictor of VO2max in men with cardiovascular disease
Purpose: Although VÌO2 max is considered the gold standard measure of cardiorespiratory fitness (CRF), it can be difficult to attain in patients with cardiovascular disease (CVD). The submaximal oxygen uptake efficiency slope (OUES) integrates cardiovascular, musculoskeletal and respiratory function during incremental exercise into a single index and has been proposed as an alternative and effort independent measure of cardiopulmonary reserve (Baba et al., 1996). The purpose of this study was to examine the relation between VÌO2 max and both submaximal absolute OUES and relative OUES (OUES.kg-1).
Methods: A total of 55 men ((mean ± SD) age, 59.08 ± 9.03 yr; VO2 max, 1.94 ± 0.53 L.min-1and 22.73 ± 5.95 mL.kg-1.min-1) were recruited during induction to a community based exercise referral program following completion of phase 2 cardiac rehabilitation. Participants performed a graded exercise test on a cycle ergometer with breath-by-breath open circuit spirometry and a 12 lead ECG. Absolute OUES and OUES.kg-1 were calculated by plotting VO2 in mL.min-1 on the x-axis, and the log transformed VE on the y-axis (VO2 = a log 10 VE + b). Exercise data up to the ventilatory anaerobic threshold (VAT) was included in the analysis.
Results: The %VÌO2 max corresponding to the VAT was 55.72 ± 11.81. Absolute OUES and OUES.kg-1 were 2164.42 ± 540.96 and 25.28 ± 5.99, respectively. There was a significant positive correlation between VÌO2 max (L.min-1) and OUES (r= 0.775; p<0.001) and between VÌO2 max (mL.kg-1.min-1) and OUES.kg-1 (r= 0.78; p<0.001).
Conclusion: Determination of VÌO2 max is not often feasible in individuals with CVD where maximal exercise testing is contraindicated or when performance may be impaired by pain, dyspnea or angina. The findings from the present study indicate that the OUES and OUES.kg-1 are significantly related to absolute and relative VÌO2 max, respectively and may be used as a valid sub maximal effort independent measure of CRF
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