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1.
Forensic Sci Res ; 7(3): 358-365, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36353327

RESUMEN

Forensic anthropologists are often responsible for the management of long-term unidentified individuals. Others have contextualised these decedents-many of whom likely belonged to socially, politically, and/or economically marginalised groups in life-as part of a larger identification crisis in the US. However, there has been little discussion surrounding how this humanitarian crisis has manifested in academic institutions, where anthropologists often provide medicolegal consultation and act as long-term stewards of the unidentified. The Identification & Repatriation Initiative was created at the Forensic Anthropology Centre at Texas State University (FACTS) to recognise and investigate unidentified human remains in long-term storage. Our paper outlines common challenges that were encountered during our initial reassessment of unidentified cases at FACTS, emphasising the detrimental impacts of inconsistent procedures, loss of context, and case fatigue. It is likely that other academic institutions face similar challenges, and by highlighting these issues we hope to help initiate a larger conversation concerning ethical stewardship of human remains in these settings. By incorporating humanitarian perspectives into forensic casework, anthropologists in academia can better advocate for the long-term unidentified.Key pointsForensic anthropologists at academic institutions are qualified to act as consultants on forensic casework when requested by jurisdictional authorities and are often responsible for the long-term management of unidentified human remains.The long-term unidentified represent a vulnerable population and academic institutions are not exempt from calls for humanitarian approaches to identification.The Identification and Repatriation Initiative was created at the Forensic Anthropology Centre at Texas State University to acknowledge and investigate unidentified human remains in long-term storage.This paper considers possible ways for humanitarian action to be incorporated into academic settings and suggests anthropologists can better advocate for the unidentified through procedural standardisation, institutional and interagency collaboration and ethical stewardship.

2.
Psychol Trauma ; 14(6): 1016-1025, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32134288

RESUMEN

OBJECTIVE: This study evaluated the effects of a mind-body skills group (MBSG) intervention on posttraumatic stress disorder (PTSD) symptoms. METHOD: Veterans (n = 108; mean age = 55.97 [SD = 11.72]; 96% male) at a PTSD specialty clinic in the Veterans Affairs Health Care System were randomized to a 10-week MBSG program or standard treatment. PTSD was the primary outcome measure. Secondary outcomes included anger, sleep, depression, anxiety, posttraumatic growth, and health-related quality of life. RESULTS: MBSG participants had significantly greater improvement in the total PTSD score after 10 weeks compared to the standard treatment group. Hyperarousal and avoidance scores significantly improved at 10 weeks and improvements in the hyperarousal symptoms were maintained at 2-month follow-up. MBSG participants also had significant decreases in anger and sleep disturbance. There were no significant differences in the other secondary outcomes. CONCLUSIONS: This MBSG intervention offers promise in helping Veterans with PTSD and its related symptoms. (PsycInfo Database Record (c) 2022 APA, all rights reserved).


Asunto(s)
Trastornos del Sueño-Vigilia , Trastornos por Estrés Postraumático , Veteranos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Calidad de Vida , Trastornos del Sueño-Vigilia/complicaciones , Trastornos por Estrés Postraumático/complicaciones , Trastornos por Estrés Postraumático/terapia , Resultado del Tratamiento
3.
JACC Cardiovasc Imaging ; 14(12): 2337-2349, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34274269

RESUMEN

OBJECTIVES: The aim of this meta-analysis was to assess the diagnostic performance of various CMR imaging parameters for evaluating acute cardiac transplant rejection. BACKGROUND: Endomyocardial biopsy is the current gold standard for detection of acute cardiac transplant rejection. Cardiac magnetic resonance (CMR) is uniquely capable of myocardial tissue characterization and may be useful as a noninvasive alternative for the diagnosis of graft rejection. METHODS: PubMed and Web of Science were searched for relevant publications reporting on the use of CMR myocardial tissue characterization for detection of acute cardiac transplant rejection with endomyocardial biopsy as the reference standard. Pooled sensitivity, specificity, and hierarchical modeling-based summary receiver-operating characteristic curves were calculated. RESULTS: Of 478 papers, 10 studies comprising 564 patients were included. The sensitivity and specificity for the detection of acute cardiac transplant rejection were 84.6 (95% CI: 65.6-94.0) and 70.1 (95% CI: 54.2-82.2) for T1, 86.5 (95% CI: 72.1-94.1) and 85.9 (95% CI: 65.2-94.6) for T2, 91.3 (95% CI: 63.9-98.4) and 67.6 (95% CI: 56.1-77.4) for extracellular volume fraction (ECV), and 50.1 (95% CI: 31.2-68.9) and 60.2 (95% CI: 36.7-79.7) for late gadolinium enhancement (LGE). The areas under the hierarchical modeling-based summary receiver-operating characteristic curve were 0.84 (95% CI: 0.81-0.87) for T1, 0.92 (95% CI: 0.89-94) for T2, 0.78 (95% CI: 0.74-0.81) for ECV, and 0.56 (95% CI: 0.51-0.60) for LGE. T2 values demonstrated the highest diagnostic accuracy, followed by native T1, ECV, and LGE (all P values <0.001 for T1, ECV, and LGE vs T2). CONCLUSIONS: T2 mapping demonstrated higher diagnostic accuracy than other CMR techniques. Native T1 and ECV provide high diagnostic use but lower diagnostic accuracy compared with T2, which was related primarily to lower specificity. LGE showed poor diagnostic performance for detection of rejection.


Asunto(s)
Medios de Contraste , Trasplante de Corazón , Gadolinio , Trasplante de Corazón/efectos adversos , Humanos , Imagen por Resonancia Magnética , Imagen por Resonancia Cinemagnética , Espectroscopía de Resonancia Magnética , Miocardio/patología , Valor Predictivo de las Pruebas , Estudios Prospectivos
4.
J Rural Health ; 37(4): 788-800, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33978989

RESUMEN

PURPOSE: To determine the effectiveness of telephone motivational coaching delivered by veteran peers to improve mental health (MH) treatment engagement among veterans. METHODS: Veterans receiving primary care from primarily rural VA community-based outpatient clinics were enrolled. Veterans not engaged in MH treatment screening positive for ≥1 MH problem(s) were randomized to receive veteran peer-delivered feedback on MH screen results and referrals plus 4 sessions of telephone motivational coaching (intervention) versus veteran peer-delivered MH results and referrals without motivational coaching (control). Blinded telephone assessments were conducted at baseline, 8, 16, and 32 weeks. Cox proportional hazard models compared MH clinician-directed treatment initiation between groups; descriptive analyses compared MH treatment retention, changes in MH symptoms, quality of life, and self-care. FINDINGS: Among 272 veterans screening positive for ≥1 MH problem(s), 45% who received veteran peer telephone motivational coaching versus 46% of control participants initiated MH treatment (primary outcome) (hazard ratio: 1.09, 95% CI: 0.76-1.57), representing no between-group differences. In contrast, veterans receiving veteran peer motivational coaching achieved significantly greater improvements in depression, posttraumatic stress disorder and cannabis use scores, quality of life domains, and adoption of some self-care strategies than controls (secondary outcomes). Qualitative data revealed that veterans who received veteran peer motivational coaching may no longer have perceived a need for MH treatment. CONCLUSIONS: Among veterans with MH problems using predominantly rural VA community clinics, telephone peer motivational coaching did not enhance MH treatment engagement, but instead had positive effects on MH symptoms, quality of life indicators, and use of self-care strategies.


Asunto(s)
Tutoría , Veteranos , Humanos , Salud Mental , Calidad de Vida , Teléfono
5.
Hum Biol ; 93(2): 83-104, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-37733460

RESUMEN

Human identification techniques have been a leading tool to hold perpetrators accountable, give families closure, and approximate faces on skulls. This project is a pilot study to critically examine three disciplines that fall under the human identification umbrella: forensic anthropology, forensic genetics, and forensic art. Current facial research in genetics focuses on data from living individuals, identifying specific single-nucleotide polymorphisms (SNPs) that influence specific regions of the face. This study assesses the translation of these regions to craniometric dimensions (interlandmark distances) of the underlying skull itself. The goal of this project is to provide information regarding the correlation of craniometric measurements and SNPs, as well as to encourage interdisciplinary work within the forensic sciences. We examined a selection of candidate SNPs currently identified in the literature to examine correlations between interlandmark distances and these SNPs within the same individual. A series of 99 craniometric landmarks were collected from 17 documented skulls from the Texas State Donated Skeletal Collection using a three-dimensional Microscribe digitizer. Criteria for inclusion in this study included European American ancestry, presence of intact skulls, and presence of associated donor blood cards collected at the time of body donation. Using these blood cards, DNA from each individual was extracted, amplified, and sequenced through next-generation sequencing for the chosen SNPs. Bioinformatics tests were then applied to observe the presence or absence of the major or minor alleles in specific locations on the genome. After determining the presence or absence of an SNP (minor allele), a set of statistical tests were performed, including Spearman's correlation between the craniometric measurements and the individual's genetic data variables; two-way hierarchical clustering and bootstrap forest modeling between variables that demonstrated significant correlation; a principal components analysis on the craniometric data (interlandmark measurements) and genetic data (SNP presence/absence) to check homogeneity of each data set; and a pairwise Procrustes analysis on the correlation of the two data sets as different groups. The results indicate correlations of varying degrees between the targeted craniofacial regions and the targeted SNPs. Eleven SNPs showed significant correlation (p < 0.05), but the correlations were not as expected and showed some interesting results. By group level there was no significant correlation, but there was correlation at the individual level. While some SNPs affected the soft tissues only, others showed correlations with the skull (hard tissue), a finding not previously reported. Combining craniometric and DNA analyses to leverage genotype-phenotype associations has great potential to expand the discourse of current facial approximation and thereby to provide new investigative tools for human identification in forensic anthropology.


Asunto(s)
Restos Mortales , Antropología Forense , Humanos , Marcadores Genéticos/genética , Proyectos Piloto , Genotipo
6.
J Forensic Sci ; 66(1): 190-201, 2021 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-32976653

RESUMEN

Estimating postmortem interval (PMI) of surface found skeletal remains is challenging. This novel study used UV-Vis-NIR spectroscopy to scan soil collected from cadaver decomposition islands (CDIs) ranging from 15- to 963-d postmortem and control soils. A decomposition product spectra model (DPS model) was constructed by deducting the control soil spectra from the CDI soil spectra for the estimation of postmortem indices: PMI (d), ADD4 , ADD10 , and ADD20 . The DPS model (n = 55) was calibrated and subjected to a full cross-validation. Calibration R2 and RPD for the DPS model ranged from 0.97 to 0.99 and from 6.1 to 9.9, respectively, for the four postmortem interval indices. Validation R2 and RPD for the DPS model ranged from 0.73 to 0.80 and from 1.9 to 2.2, respectively. The DPS model estimated postmortem intervals for three test CDIs in a clay soil under perennial grassland (test set 1; n = 3) and six CDIs in a sandy soil under a loblolly pine forest (test set 2; n = 6). Test set 1 had PMI prediction ranges from -69 to -117 days, -796 to +832 ADD4 , +552 to +2672 ADD10 , and -478 to -20 ADD20 of observed PMI. Test set 2 PMI prediction ranged from -198 to -65 days, -9923 to +2629 ADD4 , -6724 to +1321 ADD10 , and -2850 to +540 ADD20 of observed PMI. Test set 2 had poor predictions for two CDIs, for all measures of postmortem indices resulting in discussion of sampling depth, effect of body mass index (BMI), and scavenging.


Asunto(s)
Cambios Post Mortem , Espectroscopía Infrarroja Corta , Clima Tropical , Adulto , Anciano , Anciano de 80 o más Años , Índice de Masa Corporal , Cadáver , Femenino , Patologia Forense/métodos , Humanos , Masculino , Persona de Mediana Edad , Suelo/química
7.
Eval Program Plann ; 78: 101733, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31675509

RESUMEN

Despite widespread availability of yoga in the Veterans Health Administration (VA), it remains unclear how to best evaluate yoga programs. This is particularly problematic for programs aimed at veterans with mental health concerns, as evaluation typically focuses narrowly upon mental health symptom severity, even though program participants may have other health-related priorities. We analyzed responses to free-text questions on 237 surveys completed by veterans with mental health concerns enrolled in a yoga program at six VA clinics in Louisiana to characterize veteran participants' experiences with yoga. Qualitative analysis resulted in 15 domains reflecting veterans' individual health-related values and priorities. We use results to illustrate the potential for analysis of free-text responses to reveal valuable insights into patient experiences, demonstrating how these data can inform patient-centered program evaluation. The approach we present is more accessible to those responsible for decision-making about local programs than conventional methods of analyzing qualitive evaluation data.


Asunto(s)
Atención Dirigida al Paciente/organización & administración , Desarrollo de Programa/métodos , Evaluación de Programas y Proyectos de Salud/métodos , Encuestas y Cuestionarios/normas , Yoga , Ambiente , Promoción de la Salud/organización & administración , Estado de Salud , Humanos , Salud Mental , Estados Unidos , United States Department of Veterans Affairs/organización & administración
8.
Cochrane Database Syst Rev ; 2019(11)2019 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-31713856

RESUMEN

BACKGROUND: Irritable bowel syndrome (IBS) is a prevalent condition that currently lacks highly effective therapies for its management. Biofeedback has been proposed as a therapy that may help individuals learn to exert conscious control over sympatho-vagal balance as an indirect method of symptom management. OBJECTIVES: Our primary objective was to assess the efficacy and safety of biofeedback-based interventions for IBS in adults and children. SEARCH METHODS: We searched the Cochrane Inflammatory Bowel Disease (IBD) Group Specialized Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, the Cumulative Index to Nursing and Allied Health Literature (CINAHL), and the Allied and Complementary Medicine Database (AMED) from inception to 24 July 2019. We also searched reference lists from published trials, trial registries, device manufacturers, conference proceedings, theses, and dissertations. SELECTION CRITERIA: We judged randomized controlled trials to be eligible for inclusion if they met the Association for Applied Psychophysiology and Biofeedback definition of biofeedback, and if they compared a biofeedback intervention to an active, sham, or no-treatment control for the management of IBS. DATA COLLECTION AND ANALYSIS: Two authors independently screened trials for inclusion, extracted data, and assessed risk of bias. Primary outcomes were IBS global or clinical improvement scores and overall quality of life measures. Secondary outcome measures were adverse events, assessments of stool frequency and consistency, changes in abdominal pain, depression, and anxiety. For dichotomous outcomes, we calculated the risk ratio (RR) and 95% confidence interval (CI). For continuous outcomes, we calculated the mean difference (MD) and 95% CI. We used GRADE criteria to assess the overall certainty of the evidence. MAIN RESULTS: We identified eight randomized trials with a total of 300 adult participants for our analysis. We did not identify any trials in children. Four trials assessed thermal biofeedback. One trial assessed rectosigmoidal biofeedback. Two trials assessed heart rate variability biofeedback. Two trials assessed electrocutaneous biofeedback. Comparators were: no treatment (symptom monitoring group; three studies), attention control (pseudomeditation; two studies), relaxation control (one study), counseling (two studies), hypnotherapy (one study), standard therapy (one study), and sham biofeedback (one study). We judged all trials to have a high or unclear risk of bias. Global/Clinical improvement The clinical benefit of biofeedback plus standard therapy compared to standard therapy alone was uncertain (RR 4.20, 95% CI 1.40 to 12.58; 1 study, 20 participants; very low-certainty evidence). The same study also compared biofeedback plus standard therapy to sham biofeedback plus standard therapy. The clinical benefit in the biofeedback group was uncertain (RR 2.33, 95% CI 1.13 to 4.80; 1 study, 20 participants; very low-certainty evidence). The clinical benefit of heart rate biofeedback compared to hypnotherapy was uncertain when measured with the IBS severity scoring system (IBS-SSS) (MD -58.80, 95% CI -109.11 to -8.49; 1 study, 61 participants; low-certainty evidence). Compared to counseling, the effect of heart rate biofeedback was unclear when measured with a composite symptom reduction score (MD 7.03, 95% CI -51.07 to 65.13; 1 study, 29 participants; low-certainty evidence) and when evaluated for clinical response (50% improvement) (RR 1.09, 95% CI 0.48 to 2.45; 1 study, 29 participants; low-certainty evidence). The clinical benefit of thermal biofeedback used in a multi-component psychological intervention (MCPI) compared to no treatment was uncertain when measured with a composite clinical symptom reduction score (MD 30.34, 95% CI 8.47 to 52.21; 3 studies, 101 participants; very low-certainty evidence), and when evaluated as clinical response (50% improvement) (RR 2.12, 95% CI 1.24 to 3.62; 3 studies, 101 participants; very low-certainty evidence). Compared to attention control, the effects of thermal biofeedback within an MCPI were unclear when measured with a composite clinical symptom reduction score (MD 4.02, 95% CI -21.41 to 29.45; 2 studies, 80 participants; very low-certainty evidence) and when evaluated as clinical response (50% improvement) (RR 1.10, 95% CI 0.72 to 1.69, 2 studies, 80 participants; very low-certainty evidence). Quality of life A single trial used overall quality of life as an outcome measure, and reported that both the biofeedback and cognitive therapy groups improved after treatment. The trial did not note any between-group differences, and did not report any outcome data. Adverse events Only one of the eight trials explicitly reported adverse events. This study reported no adverse events in either the biofeedback or cognitive therapy groups (RD 0.00, 95% CI -0.12 to 0.12; 29 participants; low-certainty evidence). AUTHORS' CONCLUSIONS: There is currently not enough evidence to assess whether biofeedback interventions are effective for controlling symptoms of IBS. Given the positive results reported in small trials to date, biofeedback deserves further study in people with IBS. Future research should include active control groups that use high provider-participant interaction, in an attempt to balance non-specific effects of interventions between groups, and report both commonly used outcome measures (e.g. IBS-SSS) and historical outcome measures (e.g. the composite primary symptom reduction (CPSR) score) to allow for meta-analysis with previous studies. Future studies should be explicit in their reporting of adverse events.


Asunto(s)
Retroalimentación Fisiológica/fisiología , Retroalimentación Psicológica/fisiología , Síndrome del Colon Irritable/terapia , Adulto , Niño , Humanos , Ensayos Clínicos Controlados Aleatorios como Asunto , Resultado del Tratamiento
9.
J Am Chem Soc ; 141(29): 11471-11480, 2019 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-31306004

RESUMEN

Complexes with weakly coordinating ligands are often formed in chemical reactions and can play key roles in determining the reactivity, particularly in catalytic reactions. Using time-resolved X-ray absorption fine structure (XAFS) spectroscopy in combination with time-resolved IR (TRIR) spectroscopy and tungsten hexacarbonyl, W(CO)6, we are able to structurally characterize the formation of an organometallic alkane complex, determine the W-C distances, and monitor the reactivity with silane to form an organometallic silane complex. Experiments in perfluorosolvents doped with xenon afford initially the corresponding solvated complex, which is sufficiently reactive in the presence of Xe that we can then observe the coordination of Xe to the metal center, providing a unique insight into the metal-xenon bonding. These results offer a step toward elucidating the structure, bonding, and chemical reactivity of transient species by X-ray absorption spectroscopy, which has sensitivity to small structural changes. The XAFS results indicate that the bond lengths of metal-alkane (W-H-C) bond in W(CO)5(heptane) as 3.07 (±0.06) Å, which is longer than the calculated W-C (2.86 Å) for binding of the primary C-H, but shorter than the calculated W-C (3.12 Å) for the secondary C-H. A statistical average of the calculated W-C alkane bond lengths is 3.02 Å, and comparison of this value indicates that the value derived from the XAFS measurements is averaged over coordination of all C-H bonds consistent with alkane chain walking. Photolysis of W(CO)6 in the presence of HSiBu3 allows the conversion of W(CO)5(heptane) to W(CO)5(HSiBu3) with an estimated W-Si distance of 3.20 (±0.03) Å. Time-resolved TRIR and XAFS experiments following photolysis of W(CO)6 in perfluoromethylcyclohexane (PFMCH) allows the characterization of W(CO)5(PFMCH) with a W-F distance of 2.65 (±0.06) Å, and doping PFMCH with Xe allows the characterization of W(CO)5Xe with a W-Xe bond length of 3.10 (±0.02) Å.

10.
Health Place ; 47: 63-70, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28755653

RESUMEN

Most chronic illness management occurs outside clinics and hospitals, in the everyday lives of individuals. We use data from semi-structured interviews with 37 veterans from Southeastern Louisiana and Northern California to illustrate how "health work" for mental health concerns are shaped by place. Using health work as an orienting concept for analysis, we discerned variation between the two study sites in how Veterans used interacting with the natural environment, cultivating time alone, and religious practice to manage their mental health and well-being. Through these findings, we advocate for a situated notion of health work that is mindful of how health-related behaviors are shaped by place and the attributes that constitute place.


Asunto(s)
Enfermedad Crónica/psicología , Trastornos Mentales/terapia , Autocuidado , Veteranos/psicología , California , Femenino , Conductas Relacionadas con la Salud , Humanos , Entrevistas como Asunto , Louisiana , Masculino , Persona de Mediana Edad , Naturaleza , Investigación Cualitativa , Religión , Población Rural
11.
Can J Surg ; 60(1): 8-10, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28234583

RESUMEN

SUMMARY: As a physician, temperance advocate, chairman of the Grand General Indian Council of Ontario, the Supreme Chief Ranger of the Independent Order of Foresters, and mistakenly known as a Mohawk Chief, Dr. Oronhyatekha was a well-known, larger-than-life figure in North America and internationally. Since then, his memory has faded in mainstream society. Recently, however, he has re-emerged as a person of historical significance, designated as such by Parks Canada. Now the subject of the first full-length biography, co-authors Michelle Hamilton and Keith Jamieson, have separated out the true stories of his life from apocryphal ones. Although he was much more than a doctor, what follows is the story of how Oronhyatekha, a Mohawk boy baptized Peter Martin at the Six Nations of the Grand River, tenaciously pursued his dream of becoming a physician.


Asunto(s)
Indígenas Norteamericanos/historia , Médicos/historia , Canadá , Historia del Siglo XIX , Historia del Siglo XX , Humanos
12.
J Rural Health ; 32(4): 418-428, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27509291

RESUMEN

PURPOSE: Telephone motivational coaching has been shown to increase urban veteran mental health treatment initiation. However, no studies have tested telephone motivational coaching delivered by veteran peers to facilitate mental health treatment initiation and engagement. This study describes pre-implementation strategies with 8 Veterans Affairs (VA) community-based outpatient clinics in the West and Mid-South United States to adapt and implement a multisite pragmatic randomized controlled trial of telephone peer motivational coaching for rural veterans. METHODS: We used 2 pre-implementation strategies, Formative Evaluation (FE) research and Evidence-Based Quality Improvement (EBQI) meetings to adapt the intervention to stakeholders' needs and cultural contexts. FE data were qualitative, semi-structured interviews with rural veterans and VA clinic staff. Results were rapidly analyzed and presented to stakeholders during EBQI meetings to optimize the intervention implementation. FINDINGS: FE research results showed that VA clinic providers felt overwhelmed by veterans' mental health needs and acknowledged limited mental health services at VA clinics. Rural veteran interviews indicated geographical, logistical, and cultural barriers to VA mental health treatment initiation and a preference for self-care to cope with mental health symptoms. EBQI meetings resulted in several intervention adaptations, including veteran study recruitment, peer veteran coach training, and an expanded definition of mental health care outcomes. CONCLUSIONS: As the VA moves to cultivate community partnerships in order to personalize and expand access to care for rural veterans, pre-implementation processes with engaged stakeholders, such as those described here, can help guide other researchers and clinicians to achieve proactive and veteran-centered health care services.


Asunto(s)
Servicios de Salud Mental/estadística & datos numéricos , Tutoría , Aceptación de la Atención de Salud , Grupo Paritario , Veteranos/psicología , Ejercicio Físico/psicología , Humanos , Tutoría/métodos , Investigación Cualitativa , Población Rural , Automanejo , Estados Unidos , United States Department of Veterans Affairs/organización & administración , United States Department of Veterans Affairs/estadística & datos numéricos , Recursos Humanos
13.
Inorg Chem ; 55(2): 527-36, 2016 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-26605700

RESUMEN

The synthesis, photophysics, and photochemistry of a linked dyad ([Re]-[NiFe2]) containing an analogue ([NiFe2]) of the active site of [NiFe] hydrogenase, covalently bound to a Re-diimine photosensitizer ([Re]), are described. Following excitation, the mechanisms of electron transfer involving the [Re] and [NiFe2] centers and the resulting decomposition were investigated. Excitation of the [Re] center results in the population of a diimine-based metal-to-ligand charge transfer excited state. Reductive quenching by NEt3 produces the radically reduced form of [Re], [Re](-) (kq = 1.4 ± 0.1 × 10(7) M(-1) s(-1)). Once formed, [Re](-) reduces the [NiFe2] center to [NiFe2](-), and this reduction was followed using time-resolved infrared spectroscopy. The concentration dependence of the electron transfer rate constants suggests that both inter- and intramolecular electron transfer pathways are involved, and the rate constants for these processes have been estimated (kinter = 5.9 ± 0.7 × 10(8) M(-1) s(-1), kintra = 1.5 ± 0.1 × 10(5) s(-1)). For the analogous bimolecular system, only intermolecular electron transfer could be observed (kinter = 3.8 ± 0.5 × 10(9) M(-1) s(-1)). Fourier transform infrared spectroscopic studies confirms that decomposition of the dyad occurs upon prolonged photolysis, and this appears to be a major factor for the low activity of the system toward H2 production in acidic conditions.


Asunto(s)
Biomimética , Hidrogenasas/síntesis química , Fármacos Fotosensibilizantes/química , Renio/química , Aminas/química , Electroquímica , Hidrogenasas/química , Oxidación-Reducción , Espectrofotometría Infrarroja , Espectrofotometría Ultravioleta
14.
J Chem Phys ; 142(15): 154119, 2015 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-25903878

RESUMEN

In contrast to the ground state, the calculation of the infrared (IR) spectroscopy of molecular singlet excited states represents a substantial challenge. Here, we use the structural IR fingerprint of the singlet excited states of a range of coumarin dyes to assess the accuracy of density functional theory based methods for the calculation of excited state IR spectroscopy. It is shown that excited state Kohn-Sham density functional theory provides a high level of accuracy and represents an alternative approach to time-dependent density functional theory for simulating the IR spectroscopy of singlet excited states.

15.
Dalton Trans ; 44(14): 6313-9, 2015 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-25741902

RESUMEN

Visualising chemical reactions by X-ray methods is a tantalising prospect. New light sources provide the prospect for studying atomic, electronic and energy transfers accompanying chemical change by X-ray spectroscopy and inelastic scattering. Here we assess how this adventure can illuminate inorganic and catalytic chemistry. In particular X-ray inelastic scattering provides a means of exploiting X-ray free electron lasers, as a parallel to laser Raman spectroscopy.

16.
Chemistry ; 20(11): 3128-34, 2014 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-24519880

RESUMEN

At temperatures below 150 K, the photoactivated metastable endo-nitrito linkage isomer [Ni(Et4 dien)(η(2)-O,ON)(η(1)-ONO)] (Et4 dien=N,N,N',N'-tetraethyldiethylenetriamine) can be generated with 100 % conversion from the ground state nitro-(η(1)-NO2) isomer on irradiation with 500 nm light, in the single crystal by steady-state photocrystallographic techniques. Kinetic studies show the system is no longer metastable above 150 K, decaying back to the ground state nitro-(η(1)-NO2) arrangement over several hours at 150 K. Variable-temperature kinetic measurements in the range of 150-160 K show that the rate of endo-nitrito decay is highly dependent on temperature, and an activation energy of Eact =+48.6(4) kJ mol(-1) is calculated for the decay process. Pseudo-steady-state experiments, where the crystal is continually pumped by the light source for the duration of the X-ray experiment, show the production of a previously unobserved, exo-nitrito-(η(1)-ONO) linkage isomer only at temperatures close to the metastable limit (ca. 140-190 K). This exo isomer is considered to be a transient excited-state species, as it is only observed in data collected by pseudo-steady-state methods.

17.
Biochem Soc Trans ; 41(5): 1260-4, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24059517

RESUMEN

To understand the mechanism of biological processes, time-resolved methodologies are required to investigate how functionality is linked to changes in molecular structure. A number of spectroscopic techniques are available that probe local structural rearrangements with high temporal resolution. However, for macromolecules, these techniques do not yield an overall high-resolution description of the structure. Time-resolved X-ray crystallographic methods exist, but, due to both instrument availability and stringent sample requirements, they have not been widely applied to macromolecular systems, especially for time resolutions below 1 s. Recently, there has been a resurgent interest in time-resolved structural science, fuelled by the recognition that both chemical and life scientists face many of the same challenges. In the present article, we review the current state-of-the-art in dynamic structural science, highlighting applications to enzymes. We also look to the future and discuss current method developments with the potential to widen access to time-resolved studies across discipline boundaries.


Asunto(s)
Cristalografía por Rayos X/métodos , Conformación Proteica , Proteínas/química , Análisis Espectral/métodos , Rayos Láser , Estructura Molecular , Sincrotrones
18.
Mil Med ; 178(8): 854-60, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23929045

RESUMEN

The purpose of this pilot study was to evaluate the feasibility and effectiveness of a yoga program as an adjunctive therapy for improving post-traumatic stress disorder (PTSD) symptoms in Veterans with military-related PTSD. Veterans (n = 12) participated in a 6 week yoga intervention held twice a week. There was significant improvement in PTSD hyperarousal symptoms and overall sleep quality as well as daytime dysfunction related to sleep. There were no significant improvements in the total PTSD, anger, or quality of life outcome scores. These results suggest that this yoga program may be an effective adjunctive therapy for improving hyperarousal symptoms of PTSD including sleep quality. This study demonstrates that the yoga program is acceptable, feasible, and that there is good adherence in a Veteran population.


Asunto(s)
Trastornos por Estrés Postraumático/terapia , Veteranos/psicología , Yoga/psicología , Ira , Nivel de Alerta , Femenino , Humanos , Masculino , Persona de Mediana Edad , Aceptación de la Atención de Salud , Proyectos Piloto , Calidad de Vida , Trastornos Intrínsecos del Sueño/etiología , Trastornos Intrínsecos del Sueño/terapia , Trastornos por Estrés Postraumático/complicaciones , Estados Unidos
19.
J Phys Chem B ; 117(24): 7381-7, 2013 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-23718738

RESUMEN

Energy dispersive X-ray absorption spectroscopy (ED-XAS), in which the whole XAS spectrum is acquired simultaneously, has been applied to reduce the real-time for acquisition of spectra of photoinduced excited states by using a germanium microstrip detector gated around one X-ray bunch of the ESRF (100 ps). Cu K-edge XAS was used to investigate the MLCT states of [Cu(dmp)2](+) (dmp =2,9-dimethyl-1,10-phenanthroline) and [Cu(dbtmp)2](+) (dbtmp =2,9-di-n-butyl-3,4,7,8-tetramethyl-1,10-phenanthroline) with the excited states created by excitation at 450 nm (10 Hz). The decay of the longer lived complex with bulky ligands, was monitored for up to 100 ns. DFT calculations of the longer lived MLCT excited state of [Cu(dbp)2](+) (dbp =2,9-di-n-butyl-1,10-phenanthroline) with the bulkier diimine ligands, indicated that the excited state behaves as a Jahn-Teller distorted Cu(II) site, with the interligand dihedral angle changing from 83 to 60° as the tetrahedral coordination geometry flattens and a reduction in the Cu-N distance of 0.03 Å.


Asunto(s)
Cobre/química , Compuestos Organometálicos/química , Fenantrolinas/química , Teoría Cuántica , Termodinámica , Electrones , Compuestos Organometálicos/síntesis química , Espectroscopía de Absorción de Rayos X
20.
Forensic Sci Int ; 219(1-3): 57-63, 2012 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-22204892

RESUMEN

This article presents the results of a pilot study on the effects of vulture modification to human remains. A donated body from the Willed Body Donation Program was placed at the Forensic Anthropology Research Facility (FARF), an outdoor human decomposition laboratory located at Texas State University-San Marcos. The effects of vulture scavenging on the timing and sequence, and the rate of skeletonization, disarticulation, and dispersal were observed via a motion sensing camera and direct observation. Using GIS (Geographic Information Systems) and GPS (Global Positioning System) technologies and spatial analytical methods, the transport of skeletal elements was mapped in order to analyze dispersal and terrain-influenced patterns of active vulture scavenging. Results showed that the initial scavenging took place 37 days after placement at FARF. This delay in scavenging differs from previous research. After the initial appearance of the vultures, the body was reduced from a fully-fleshed individual to a skeleton within only 5h. This underscores the potential for errors in postmortem interval estimations made at vulture scavenged scenes. Additionally, spatial analysis showed that skeletal elements were dispersed by vultures to lower elevations, and that the disarticulation and dispersal of the skeletal elements occurs early in the scavenging sequence.


Asunto(s)
Carnívoros , Falconiformes , Conducta Alimentaria , Adulto , Animales , Femenino , Antropología Forense , Patologia Forense , Sistemas de Información Geográfica , Humanos , Proyectos Piloto , Factores de Tiempo
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