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1.
J Adv Nurs ; 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38308427

RESUMO

AIM: To identify Attributes, Characteristics and Demonstrations of nursing practice from both nurses' and people perspectives in today's healthcare environments. A secondary aim was to identify relevant differences between female and male nurses in the context of ACDs. DESIGN: This systematic review was informed by the Joanna Briggs Institute Convergent Integrated Approach to Mixed Study Systematic Reviews. METHODS: The search included articles ranging from the years 2000 to 2023 across 10 electronic databases and multiple grey literature outlets. McMaster critical review forms and the Mixed Methods Appraisal Tool were used to appraise article quality. The Convergent Integrated Approach to Mixed Study Systematic Reviews was used to guide data synthesis. RESULTS: Twenty articles were included in this review, 13 qualitative, five quantitative and two mixed-methods studies. Three themes emerged, including knowledge, practice skills and interpersonal relationships. Differences in Attributes, Characteristics and Demonstrations of professional practice between women and men in nursing were also explored. CONCLUSION: Findings suggest that evolving healthcare environments challenge nurses to remain focused on patient-centred and compassionate care. The review also supports nurses caring in a manner that empowers people, increases well-being, and reduces suffering. IMPACT: Identified characteristics and attributes of nursing practice, including emphasis on continuous learning, interpersonal relationships and compassion, have a profound impact on nursing. Nurses should remain adaptable, compassionate and patient-focused in an ever-evolving healthcare environment. These foundational care principles are necessary for improving patient outcomes, enhancing trust between people and healthcare providers, and increasing inclusivity and diversity in the nursing workforce. WIDER GLOBAL COMMUNITY: Nurses worldwide should strive to embody these attributes to provide high-quality, patient-centred care in an inclusive environment in today's demanding healthcare environment. Gender-specific differences in the perception and expression of professional Attributes, Characteristics and Demonstrations can inform inclusion and diversity efforts in the workplace. REPORTING METHOD: This systematic review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. PATIENT OR PUBLIC CONTRIBUTION: No Patient or Public Contribution.

2.
Circulation ; 145(13): e776-e801, 2022 03 29.
Artigo em Inglês | MEDLINE | ID: mdl-35164535

RESUMO

Out-of-hospital cardiac arrest is a global public health issue experienced by ≈3.8 million people annually. Only 8% to 12% survive to hospital discharge. Early defibrillation of shockable rhythms is associated with improved survival, but ensuring timely access to defibrillators has been a significant challenge. To date, the development of public-access defibrillation programs, involving the deployment of automated external defibrillators into the public space, has been the main strategy to address this challenge. Public-access defibrillator programs have been associated with improved outcomes for out-of-hospital cardiac arrest; however, the devices are used in <3% of episodes of out-of-hospital cardiac arrest. This scientific statement was commissioned by the International Liaison Committee on Resuscitation with 3 objectives: (1) identify known barriers to public-access defibrillator use and early defibrillation, (2) discuss established and novel strategies to address those barriers, and (3) identify high-priority knowledge gaps for future research to address. The writing group undertook systematic searches of the literature to inform this statement. Innovative strategies were identified that relate to enhanced public outreach, behavior change approaches, optimization of static public-access defibrillator deployment and housing, evolved automated external defibrillator technology and functionality, improved integration of public-access defibrillation with existing emergency dispatch protocols, and exploration of novel automated external defibrillator delivery vectors. We provide evidence- and consensus-based policy suggestions to enhance public-access defibrillation and guidance for future research in this area.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Parada Cardíaca Extra-Hospitalar , Reanimação Cardiopulmonar/métodos , Desfibriladores , Cardioversão Elétrica/métodos , Humanos , Parada Cardíaca Extra-Hospitalar/terapia , Alta do Paciente , Guias de Prática Clínica como Assunto
3.
Pediatr Blood Cancer ; 70(8): e30398, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37140091

RESUMO

BACKGROUND: Acute lymphoblastic leukemia (ALL) remains one of the most common causes of cancer-related mortality in children. Phosphoinositide 3-kinases (PI3Ks) are a family of lipid kinases, and aberrations in the PI3K pathway are associated with several hematological malignancies, including ALL. Duvelisib (Copiktra) is an orally available, small molecule dual inhibitor of PI3Kδ and PI3Kγ, that is Food and Drug Administration (FDA) approved for the treatment of relapsed/refractory chronic lymphocytic leukemia and small lymphocytic lymphoma. Here, we report the efficacy of duvelisib against a panel of pediatric ALL patient-derived xenografts (PDXs). PROCEDURES: Thirty PDXs were selected for a single mouse trial based on PI3Kδ (PIK3CD) and PI3Kγ (PIK3CG) expression and mutational status. PDXs were grown orthotopically in NSG (NOD.Cg-Prkdcscid IL2rgtm1Wjl /SzJAusb) mice, and engraftment was evaluated by enumerating the proportion of human versus mouse CD45+ cells (%huCD45+ ) in the peripheral blood. Treatment commenced when the %huCD45+ reached greater than or equal to 1%, and events were predefined as %huCD45+ greater than or equal to 25% or leukemia-related morbidity. Duvelisib was administered per oral (50 mg/kg, twice daily for 28 days). Drug efficacy was assessed by event-free survival and stringent objective response measures. RESULTS: PI3Kδ and PI3Kγ mRNA expression was significantly higher in B-lineage than T-lineage ALL PDXs (p-values <.0001). Duvelisib was well-tolerated and reduced leukemia cells in the peripheral blood in four PDXs, but with only one objective response. There was no obvious relationship between duvelisib efficacy and PI3Kδ or PI3Kγ expression or mutation status, nor was the in vivo response to duvelisib subtype dependent. CONCLUSIONS: Duvelisib demonstrated limited in vivo activity against ALL PDXs.


Assuntos
Leucemia Linfocítica Crônica de Células B , Linfoma de Células B , Leucemia-Linfoma Linfoblástico de Células Precursoras , Criança , Humanos , Animais , Camundongos , Xenoenxertos , Fosfatidilinositol 3-Quinases , Camundongos Endogâmicos NOD , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Linfoma de Células B/patologia , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamento farmacológico
4.
Pediatr Blood Cancer ; : e30503, 2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37339930

RESUMO

BACKGROUND: While children with acute lymphoblastic leukemia (ALL) experience close to a 90% likelihood of cure, the outcome for certain high-risk pediatric ALL subtypes remains dismal. Spleen tyrosine kinase (SYK) is a prominent cytosolic nonreceptor tyrosine kinase in pediatric B-lineage ALL (B-ALL). Activating mutations or overexpression of Fms-related receptor tyrosine kinase 3 (FLT3) are associated with poor outcome in hematological malignancies. TAK-659 (mivavotinib) is a dual SYK/FLT3 reversible inhibitor, which has been clinically evaluated in several other hematological malignancies. Here, we investigate the in vivo efficacy of TAK-659 against pediatric ALL patient-derived xenografts (PDXs). METHODS: SYK and FLT3 mRNA expression was quantified by RNA-seq. PDX engraftment and drug responses in NSG mice were evaluated by enumerating the proportion of human CD45+ cells (%huCD45+ ) in the peripheral blood. TAK-659 was administered per oral at 60 mg/kg daily for 21 days. Events were defined as %huCD45+ ≥ 25%. In addition, mice were humanely killed to assess leukemia infiltration in the spleen and bone marrow (BM). Drug efficacy was assessed by event-free survival and stringent objective response measures. RESULTS: FLT3 and SYK mRNA expression was significantly higher in B-lineage compared with T-lineage PDXs. TAK-659 was well tolerated and significantly prolonged the time to event in six out of eight PDXs tested. However, only one PDX achieved an objective response. The minimum mean %huCD45+ was significantly reduced in five out of eight PDXs in TAK-659-treated mice compared with vehicle controls. CONCLUSIONS: TAK-659 exhibited low to moderate single-agent in vivo activity against pediatric ALL PDXs representative of diverse subtypes.

5.
J Interprof Care ; 36(5): 735-749, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35129041

RESUMO

Interprofessional collaboration (IPC) is a practice model to promote healthcare quality. Since the World Health Organization highlighted the importance of IPC in 2010, a large volume of IPC-related research has been published. Multiple systematic reviews have been conducted to synthesize the literature from varying perspectives. Although systematic reviews are a compelling approach to synthesizing primary research, a systematic meta-review was needed to summarize the systematic reviews to offer information for healthcare professionals, researchers, and policymakers. This systematic meta-review was designed to synthesize the systematic reviews of IPC, emphasizing the IPC-related facilitators, barriers, and outcomes between 2010 and 2020. An electronic search for systematic reviews was performed in December 2020. The databases searched included PubMed, CINAHL, PsycINFO, and Cochrane Database of Systematic Reviews. Thirty-six systematic reviews met the inclusion criteria. Factors facilitating or impeding IPC were classified into three levels: organization, team, and individual. Major outcomes related to patients, healthcare professionals, and organizations. The facilitators, barriers, and outcomes are mutually interrelated. Highly effective collaboration is a process from relationship building to working together and collaborating. Improving IPC requires organizational, teams, and individuals' combined efforts. When highly effective collaborations occur, all stakeholders can benefit - organizations, professionals, and patients.


Assuntos
Comportamento Cooperativo , Pessoal de Saúde , Relações Interprofissionais , Atenção à Saúde/organização & administração , Pessoal de Saúde/psicologia , Humanos , Qualidade da Assistência à Saúde , Revisões Sistemáticas como Assunto
6.
Circulation ; 142(16_suppl_1): S41-S91, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-33084391

RESUMO

This 2020 International Consensus on Cardiopulmonary Resuscitation (CPR) and Emergency Cardiovascular Care Science With Treatment Recommendations on basic life support summarizes evidence evaluations performed for 22 topics that were prioritized by the Basic Life Support Task Force of the International Liaison Committee on Resuscitation. The evidence reviews include 16 systematic reviews, 5 scoping reviews, and 1 evidence update. Per agreement within the International Liaison Committee on Resuscitation, new or revised treatment recommendations were only made after a systematic review. Systematic reviews were performed for the following topics: dispatch diagnosis of cardiac arrest, use of a firm surface for CPR, sequence for starting CPR (compressions-airway-breaths versus airway-breaths-compressions), CPR before calling for help, duration of CPR cycles, hand position during compressions, rhythm check timing, feedback for CPR quality, alternative techniques, public access automated external defibrillator programs, analysis of rhythm during chest compressions, CPR before defibrillation, removal of foreign-body airway obstruction, resuscitation care for suspected opioid-associated emergencies, drowning, and harm from CPR to victims not in cardiac arrest. The topics that resulted in the most extensive task force discussions included CPR during transport, CPR before calling for help, resuscitation care for suspected opioid-associated emergencies, feedback for CPR quality, and analysis of rhythm during chest compressions. After discussion of the scoping reviews and the evidence update, the task force prioritized several topics for new systematic reviews.


Assuntos
Reanimação Cardiopulmonar/normas , Doenças Cardiovasculares/terapia , Serviços Médicos de Emergência/normas , Cuidados para Prolongar a Vida/normas , Adulto , Reanimação Cardiopulmonar/métodos , Doenças Cardiovasculares/diagnóstico , Desfibriladores , Prática Clínica Baseada em Evidências , Humanos , Parada Cardíaca Extra-Hospitalar/diagnóstico , Parada Cardíaca Extra-Hospitalar/terapia
7.
J Adv Nurs ; 76(5): 1211-1220, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32056270

RESUMO

AIMS: The aim of this study was to investigate the lived experiences of male nurses in today's healthcare environment to understand the persistently low numbers of men in nursing. DESIGN: This study used interpretive description methodology, which aligns with nursing's approach to knowledge discovery by acknowledging the evolution and complexity of shared and individual experiences. METHODS: Participants, (N = 11), were recruited through the American Association for Men in Nursing using purposive sampling. Focused interviews were conducted between May 2018 - June 2018. Interviews were semi-structured, guided by open-ended questions and video and audio recorded. Data were analysed according to study design with categories and themes extracted using reliability measures. RESULTS: This study's findings reflected the unique experiences of each participant in a primarily female dominated work environment in clinical and academic settings. Our study identified thematic categories of role expectations and workplace relations for the men in the study. Role expectations were influenced by sociocultural views, professional acceptance and patient/family perceptions. Workplace relations were associated with being male, social cliques and peer support. CONCLUSION: Participants shared similar and distinctly individual experiences. Findings from this study indicate there has been progress toward improving male presence in nursing but additional efforts are needed to increase inclusivity. Findings can be used to make recommendations for professional change in nursing, strengthen diversity by refining ways to recruit more men, enhance patients' experiences and improve experiences for future male nurses. IMPACT: This study addressed low numbers of men in nursing. Main findings included role expectations and workplace relations and how they are experienced by men in nursing. Findings from this research have a multidisciplinary impact in the workplace, and affect care of patients and their families.


Assuntos
Atitude do Pessoal de Saúde , Relações Interpessoais , Papel do Profissional de Enfermagem/psicologia , Enfermeiros/psicologia , Papel Profissional/psicologia , Local de Trabalho/psicologia , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Reprodutibilidade dos Testes , Estados Unidos
8.
Sensors (Basel) ; 20(19)2020 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-32993141

RESUMO

Detailed information about temperature distribution can be important to understand structural behavior in fire. This study develops a method to image three-dimensional temperature distributions in steel-concrete composite slabs using distributed fiber optic sensors. The feasibility of the method is explored using six 1.2 m × 0.9 m steel-concrete composite slabs instrumented with distributed sensors and thermocouples subjected to fire for over 3 h. Dense point clouds of temperature in the slabs were measured using the distributed sensors. The results show that the distributed sensors operated at material temperatures up to 960 °C with acceptable accuracy for many structural fire applications. The measured non-uniform temperature distributions indicate a spatially distributed thermal response in steel-concrete composite slabs, which can only be adequately captured using approaches that provide a high density of through-depth data points.

9.
Development ; 143(12): 2056-65, 2016 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-27302396

RESUMO

For over a century, embryologists who studied cellular motion in early amniotes generally assumed that morphogenetic movement reflected migration relative to a static extracellular matrix (ECM) scaffold. However, as we discuss in this Review, recent investigations reveal that the ECM is also moving during morphogenesis. Time-lapse studies show how convective tissue displacement patterns, as visualized by ECM markers, contribute to morphogenesis and organogenesis. Computational image analysis distinguishes between cell-autonomous (active) displacements and convection caused by large-scale (composite) tissue movements. Modern quantification of large-scale 'total' cellular motion and the accompanying ECM motion in the embryo demonstrates that a dynamic ECM is required for generation of the emergent motion patterns that drive amniote morphogenesis.


Assuntos
Matriz Extracelular/metabolismo , Morfogênese , Movimento (Física) , Animais , Humanos , Invertebrados/embriologia , Organogênese
10.
Small ; 15(34): e1902728, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31276302

RESUMO

Carrier interactions in 2D nanostructures are of central importance not only in condensed-matter physics but also for a wide range of optoelectronic and photonic applications. Here, new insights into the behavior of photoinduced carriers in layered platinum diselenide (PtSe2 ) through ultrafast time-resolved pump-probe and nonlinear optical measurements are presented. The measurements reveal the temporal evolution of carrier relaxation, chemical potential and bandgap renormalization in PtSe2 . These results imply that few-layer PtSe2 has a semiconductor-like carrier relaxation instead of a metal-like one. The relaxation follows a triple-exponential decay process and exhibits thickness-dependent relaxation times. This occurs along with a band-filling effect, which can be controlled based on the number of layers and may be applied in saturable absorption for generating ultrafast laser pulses. The findings may provide means to study many-body physics in 2D materials as well as potentially leading to applications in the field of optoelectronics and ultrafast photonics.

11.
Arthroscopy ; 35(9): 2724-2732, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31500761

RESUMO

PURPOSE: To describe the injury rates, mechanisms, time loss, and rates of surgery for hip/groin injuries in National Collegiate Athletic Association (NCAA) athletes across 25 collegiate sports during the 2009/10 to 2013/14 academic years. METHODS: Data from the 2009/10 to 2013/14 academic years were obtained from the NCAA Injury Surveillance Program (ISP). Rates of hip/groin injuries, mechanism of injury, time lost from competition, and surgical treatment were calculated. Differences between sex-comparable sports were quantified using rate ratios and injury proportion ratios. A sport-specific biomechanical classification system, which included cutting, impingement, overhead/asymmetric, endurance, and flexibility sports, was applied for subgroup analysis. RESULTS: In total, 1,984 hip injuries were reported in 25 NCAA sports, including 9 male and female sports, 3 male-only sports, and 4 female-only sports between the years 2009/10 and 2013/14, resulting in an overall hip injury rate of 53.1/100,000 athletic exposures (AEs). In sex-comparable sports, (basketball, cross-country, lacrosse, ice hockey, indoor track, outdoor track, soccer, swimming, and tennis), men were more commonly affected than women (59.53 vs 42.27 per 100,000 AEs respectively; rate ratio, 1.41; 95% confidence interval, 1.28-1.55). Subgroup analysis demonstrated that the highest rate of hip injuries per 100,000 AEs occurred in impingement sports (96.9). Endurance sports had the highest proportion of injured athletes with time lost >14 days (9.5%). For impingement-type sports, the most common mechanism of injury was no apparent contact (48.2%). The rate of athletes undergoing surgery per 100,000 AEs was highest in impingement-type sports (2.0). CONCLUSIONS: We have identified that impingement-type sports are most frequently associated with hip injuries. Additionally, this study demonstrates that hip injuries sustained in athletes who played impingement-type sports had a significantly higher rate of surgical intervention than other sport classifications. LEVEL OF EVIDENCE: Level III, prognostic study.


Assuntos
Atletas , Traumatismos em Atletas/epidemiologia , Lesões do Quadril/epidemiologia , Estudantes , Humanos , Incidência , Estados Unidos/epidemiologia
12.
Vet Radiol Ultrasound ; 60(5): 543-551, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31146303

RESUMO

Volumetric imaging (VOL), a three-dimensional magnetic resonance imaging (MRI) technique, has been described in the literature for evaluation of the human brain. It offers several advantages over conventional two-dimensional (2D) spin echo (SE), allowing rapid, whole-brain, isotropic imaging with submillimeter voxels. This retrospective, observational study compares the use of 2D T1-weighted SE (T1W SE), with T1W VOL, for the evaluation of dogs with clinical signs of intracranial disease. Brain MRI images from 160 dogs who had T1W SE and T1W VOL sequences acquired pre- and postcontrast, were reviewed for presence and characteristics of intracranial lesions. Twenty-nine of 160 patients were found to have intracranial lesions, all visible on both sequences. Significantly better grey-white matter (GWM) differentiation was identified with T1W VOL (P < .001), with fair agreement between the two sequences (weighted κ = 0.35). Excluding a mild reduction in lesion intensity in three dogs precontrast on the T1W VOL images compared to T1W SE, and meningeal enhancement noted on the T1W VOL images in one dog, not identified on T1W SE, there was otherwise complete agreement between the two sequences. The T1W VOL sequence provided equivalent lesion evaluation and significantly improved GWM differentiation. Images acquired were of comparable diagnostic quality to those produced using a conventional T1W SE technique, for assessment of lesion appearance, number, location, mass effect, and postcontrast enhancement. T1W VOL, therefore, provides a suitable alternative T1W sequence for canine brain evaluation and can facilitate a reduction in total image acquisition time.


Assuntos
Encefalopatias/veterinária , Doenças do Cão/diagnóstico por imagem , Imageamento Tridimensional/veterinária , Imageamento por Ressonância Magnética/veterinária , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encefalopatias/diagnóstico por imagem , Encefalopatias/patologia , Cães , Feminino , Imageamento Tridimensional/métodos , Imageamento por Ressonância Magnética/métodos , Masculino , Estudos Retrospectivos
13.
J Craniofac Surg ; 29(3): 796-799, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29489569

RESUMO

Removal of the fronto-orbital bandeau is one of the most critical components for procedures designed to correct anomalies of the craniofacial skeleton and remodel the anterior calvarial vault. It is also used to improve exposure of the anterior cranial fossa. It is arguably one of the more difficult portions of some craniofacial procedures. While the technique for fronto-orbito-sphenoid osteotomy has been frequently described, it has only been minimally detailed. Separation of bone in this region remains challenging due to the bone thickness, adjacent vital structures, and limited direct visibility. The present paper describes the anatomy of this particular region, which the authors have termed the "triple point", to facilitate successful osteotomy and avoid potential injury.


Assuntos
Anormalidades Craniofaciais/cirurgia , Osso Frontal/cirurgia , Órbita/cirurgia , Osteotomia/métodos , Osso Esfenoide/anatomia & histologia , Osso Esfenoide/cirurgia , Fossa Craniana Anterior/anatomia & histologia , Fossa Craniana Anterior/cirurgia , Osso Frontal/anatomia & histologia , Humanos , Órbita/anatomia & histologia
14.
J Biol Chem ; 291(47): 24406-24417, 2016 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-27707879

RESUMO

MAGI-1 is a multidomain cytosolic scaffolding protein that in the kidney is specifically located at the podocyte slit diaphragm, a specialized junction that is universally injured in proteinuric diseases. There it interacts with several essential molecules, including nephrin and neph1, which are required for slit diaphragm formation and as an intracellular signaling hub. Here, we show that diminished MAGI-1 expression in cultured podocytes reduced nephrin and neph1 membrane localization and weakened tight junction integrity. Global magi1 knock-out mice, however, demonstrated normal glomerular histology and function into adulthood. We hypothesized that a second mild but complementary genetic insult might induce glomerular disease susceptibility in these mice. To identify such a gene, we utilized the developing fly eye to test for functional complementation between MAGI and its binding partners. In this way, we identified diminished expression of fly Hibris (nephrin) or Roughest (neph1) as dramatically exacerbating the effects of MAGI depletion. Indeed, when these combinations were studied in mice, the addition of nephrin, but not neph1, heterozygosity to homozygous deletion of MAGI-1 resulted in spontaneous glomerulosclerosis. In cultured podocytes, MAGI-1 depletion reduced intercellular contact-induced Rap1 activation, a pathway critical for proper podocyte function. Similarly, magi1 knock-out mice showed diminished glomerular Rap1 activation, an effect dramatically enhanced by concomitant nephrin haploinsufficiency. Finally, combined overexpression of MAGI-1 and nephrin increased Rap1 activation, but not when substituting a mutant MAGI-1 that cannot bind nephrin. We conclude that the interaction between nephrin and MAGI-1 regulates Rap1 activation in podocytes to maintain long term slit diaphragm structure.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas de Membrana/metabolismo , Podócitos/metabolismo , Proteínas rap1 de Ligação ao GTP/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/genética , Animais , Moléculas de Adesão Celular , Ativação Enzimática , Glomerulosclerose Segmentar e Focal/genética , Glomerulosclerose Segmentar e Focal/metabolismo , Glomerulosclerose Segmentar e Focal/patologia , Guanilato Quinases , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Proteínas rap1 de Ligação ao GTP/genética
15.
J Struct Eng (N Y N Y) ; 143(1)2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28239230

RESUMO

This paper presents high temperature measurements using a Brillouin scattering-based fiber optic sensor and the application of the measured temperatures and building code recommended material parameters into enhanced thermomechanical analysis of simply supported steel beams subjected to combined thermal and mechanical loading. The distributed temperature sensor captures detailed, nonuniform temperature distributions that are compared locally with thermocouple measurements with less than 4.7% average difference at 95% confidence level. The simulated strains and deflections are validated using measurements from a second distributed fiber optic (strain) sensor and two linear potentiometers, respectively. The results demonstrate that the temperature-dependent material properties specified in the four investigated building codes lead to strain predictions with less than 13% average error at 95% confidence level and that the Europe building code provided the best predictions. However, the implicit consideration of creep in Europe is insufficient when the beam temperature exceeds 800°C.

16.
Fire Saf J ; 91: 524-531, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28966437

RESUMO

A series of tests was conducted on six 2.7 m × 3.7 m shear wall specimens consisting of cold-formed steel framing sheathed on one side with sheet steel adhered to gypsum board and on the opposite side with plain gypsum board. The specimens were subjected to various sequences of simulated seismic shear deformation and fire exposure to study the influence of multi-hazard interactions on the lateral load resistance of the walls. The test program was designed to complement a parallel effort at the University of California, San Diego to investigate a six-story building subjected to earthquakes and fires. The test results reported here indicate that the fire exposure caused a shift in the failure mode of the walls from local buckling of the sheet steel in cases without fire exposure, to global buckling of the sheet steel with an accompanying 35 % reduction in lateral load capacity after the wall had been exposed to fire. This behavior appears to be predictable, which is encouraging from the standpoint of residual lateral load capacity under these severe multi-hazard actions.

17.
Langmuir ; 32(6): 1577-84, 2016 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-26794208

RESUMO

Polymerization of substrate-supported bilayers composed of dienoylphosphatidylcholine (PC) lipids is known to greatly enhance their chemical and mechanical stability; however, the effects of polymerization on membrane fluidity have not been investigated. Here planar supported lipid bilayers (PSLBs) composed of dienoyl PCs on glass substrates were examined to assess the degree to which UV-initiated polymerization affects lateral lipid mobility. Fluorescence recovery after photobleaching (FRAP) was used to measure the diffusion coefficients (D) and mobile fractions of rhodamine-DOPE in unpolymerized and polymerized PSLBs composed of bis-sorbyl phosphatidylcholine (bis-SorbPC), mono-sorbyl-phosphatidylcholine (mono-SorbPC), bis-dienoyl-phosphatidylcholine (bis-DenPC), and mono-dienoyl phosphatidylcholine (mono-DenPC). Polymerization was performed in both the Lα and Lß phase for each lipid. In all cases, polymerization reduced membrane fluidity; however, measurable lateral diffusion was retained which is attributed to a low degree of polymerization. The D values for sorbyl lipids were less than those of the denoyl lipids; this may be a consequence of the distal location of polymerizable group in the sorbyl lipids which may facilitate interleaflet bonding. The D values measured after polymerization were 0.1-0.8 of those measured before polymerization, a range that corresponds to fluidity intermediate between that of a Lα phase and a Lß phase. This D range is comparable to ratios of D values reported for liquid-disordered (Ld) and liquid-ordered (Lo) lipid phases and indicates that the effect of UV polymerization on lateral diffusion in a dienoyl PSLB is similar to the transition from a Ld phase to a Lo phase. The partial retention of fluidity in UV-polymerized PSLBs, their enhanced stability, and the activity of incorporated transmembrane proteins and peptides is discussed.


Assuntos
Bicamadas Lipídicas/química , Fluidez de Membrana/efeitos da radiação , Fosfatidilcolinas/química , Fosfatidiletanolaminas/química , Rodaminas/química , Difusão , Recuperação de Fluorescência Após Fotodegradação , Bicamadas Lipídicas/efeitos da radiação , Fosfatidilcolinas/efeitos da radiação , Fosfatidiletanolaminas/efeitos da radiação , Polimerização , Rodaminas/efeitos da radiação , Temperatura de Transição , Raios Ultravioleta
18.
Dev Dyn ; 244(11): 1357-74, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26293597

RESUMO

We introduce a new subfield of the recently created field of Evolutionary-Developmental-Anthropology (Evo-Devo-Anth): Evolutionary-Developmental-Pathology-and-Anthropology (Evo-Devo-P'Anth). This subfield combines experimental and developmental studies of nonhuman model organisms, biological anthropology, chordate comparative anatomy and evolution, and the study of normal and pathological human development. Instead of focusing on other organisms to try to better understand human development, evolution, anatomy, and pathology, it places humans as the central case study, i.e., as truly model organism themselves. We summarize the results of our recent Evo-Devo-P'Anth studies and discuss long-standing questions in each of the broader biological fields combined in this subfield, paying special attention to the links between: (1) Human anomalies and variations, nonpentadactyly, homeotic transformations, and "nearest neighbor" vs. "find and seek" muscle-skeleton associations in limb+facial muscles vs. other head muscles; (2) Developmental constraints, the notion of "phylotypic stage," internalism vs. externalism, and the "logic of monsters" vs. "lack of homeostasis" views about human birth defects; (3) Human evolution, reversions, atavisms, paedomorphosis, and peromorphosis; (4) Scala naturae, Haeckelian recapitulation, von Baer's laws, and parallelism between phylogeny and development, here formally defined as "Phylo-Devo parallelism"; and (5) Patau, Edwards, and Down syndrome (trisomies 13, 18, 21), atavisms, apoptosis, heart malformations, and medical implications.


Assuntos
Evolução Biológica , Anatomia/métodos , Anatomia Comparada , Animais , Antropologia/métodos , Cromossomos Humanos Par 18 , Anormalidades Congênitas/genética , Anormalidades Congênitas/fisiopatologia , Biologia do Desenvolvimento/métodos , Síndrome de Down/genética , Síndrome de Down/fisiopatologia , Deformidades Congênitas do Pé/genética , Deformidades Congênitas da Mão/genética , Cardiopatias Congênitas/genética , Homeostase , Humanos , Cariotipagem , Patologia/métodos , Filogenia , Trissomia , Síndrome da Trissomía do Cromossomo 18
19.
Opt Express ; 23(20): 26486-98, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26480162

RESUMO

Off-normal, polarization dependent second-harmonic generation (SHG) measurements were performed ex situ on plasmonic nanostructures grown by self-assembly on nanopatterned templates. These exploratory studies of Ag nanoparticle (NP) arrays show that the sensitivity of SHG to the local fields, which are modified by the NP size, shape and distribution, makes it a promising fixed wavelength characterization technique that avoids the complexity of spectroscopic SHG. The off-normal geometry provides access to the out-of-plane SH response, which is typically an order-of-magnitude larger than the in-surface-plane response measured using normal incidence, for example in SHG microscopy. By choosing the plane of incidence orthogonal to the NP array direction, it was shown that the p-polarized SH response, as a function of input polarization, is very sensitive to NP morphology, with a change of 20% in the aspect ratio of the NPs producing a variation of a factor of 30 in the easily measureable ratio of the p-polarized SH field strength for s- and p-polarized input. The results show that such a fixed geometry could be used for the in situ characterization of anisotropic nanostructure morphology during growth by self-assembly, which could be particularly useful in situations where rotating the sample may be neither desirable nor easily accomplished.

20.
J Prof Nurs ; 53: 123-130, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38997191

RESUMO

BACKGROUND: Nursing shortages are occurring due to decreased student enrollment, nurse burnout, staffing deficits, nurse retirements, and increasingly low numbers of nursing faculty. Men are an untapped resource that can offset these crises. However, men's presence in nursing remains underwhelming. Changes aimed at improving diversity and inclusivity related to men's presence is needed in the nursing workforce. PURPOSE: Explore men's experiences in modern nursing environments to identify barriers to men's presence in nursing faculty and clinical workforce roles. METHOD: This study used interpretive description design. Data were collected through individual and group interviews. Interviews were video recorded. Interview questions were semi-structured and open ended. Data were analyzed using thematic analysis. RESULTS: Two themes were identified and reflected men's experiences in nursing: educational and professional change. Subthemes for educational change included increasing numbers of men in student and faculty roles; instructional change; admission, retention, and advising. Subthemes for professional change included inclusive hiring practices; healthy working environments; and leadership outcomes. CONCLUSION: Findings constitute calls for action. Change implementation should address barriers to diversity and inclusivity related to men's presence in nursing. Recommendations and strategies presented can guide change implementation. Change implementation is expected to strengthen the nursing profession.


Assuntos
Docentes de Enfermagem , Enfermeiros , Estudantes de Enfermagem , Humanos , Masculino , Enfermeiros/psicologia , Estudantes de Enfermagem/psicologia , Adulto , Pesquisa Qualitativa , Local de Trabalho/psicologia , Pessoa de Meia-Idade , Entrevistas como Assunto
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