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1.
Nature ; 623(7989): 938-941, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37783227

RESUMO

Large constellations of bright artificial satellites in low Earth orbit pose significant challenges to ground-based astronomy1. Current orbiting constellation satellites have brightnesses between apparent magnitudes 4 and 6, whereas in the near-infrared Ks band, they can reach magnitude 2 (ref. 2). Satellite operators, astronomers and other users of the night sky are working on brightness mitigation strategies3,4. Radio emissions induce further potential risk to ground-based radio telescopes that also need to be evaluated. Here we report the outcome of an international optical observation campaign of a prototype constellation satellite, AST SpaceMobile's BlueWalker 3. BlueWalker 3 features a 64.3 m2 phased-array antenna as well as a launch vehicle adaptor (LVA)5. The peak brightness of the satellite reached an apparent magnitude of 0.4. This made the new satellite one of the brightest objects in the night sky. Additionally, the LVA reached an apparent V-band magnitude of 5.5, four times brighter than the current International Astronomical Union recommendation of magnitude 7 (refs. 3,6); it jettisoned on 10 November 2022 (Universal Time), and its orbital ephemeris was not publicly released until 4 days later. The expected build-out of constellations with hundreds of thousands of new bright objects1 will make active satellite tracking and avoidance strategies a necessity for ground-based telescopes.

2.
Development ; 150(17)2023 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37602510

RESUMO

Positional information in development often manifests as stripes of gene expression, but how stripes form remains incompletely understood. Here, we use optogenetics and live-cell biosensors to investigate the posterior brachyenteron (byn) stripe in early Drosophila embryos. This stripe depends on interpretation of an upstream ERK activity gradient and the expression of two target genes, tailless (tll) and huckebein (hkb), that exert antagonistic control over byn. We find that high or low doses of ERK signaling produce transient or sustained byn expression, respectively. Although tll transcription is always rapidly induced, hkb converts graded ERK inputs into a variable time delay. Nuclei thus interpret ERK amplitude through the relative timing of tll and hkb transcription. Antagonistic regulatory paths acting on different timescales are hallmarks of an incoherent feedforward loop, which is sufficient to explain byn dynamics and adds temporal complexity to the steady-state model of byn stripe formation. We further show that 'blurring' of an all-or-none stimulus through intracellular diffusion non-locally produces a byn stripe. Overall, we provide a blueprint for using optogenetics to dissect developmental signal interpretation in space and time.


Assuntos
Núcleo Celular , Drosophila , Animais , Difusão , Embrião de Mamíferos , Optogenética
3.
Phys Chem Chem Phys ; 26(17): 13316-13326, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38639914

RESUMO

In this article we present a quantitative analysis of the second positive system of molecular nitrogen and the first negative system of the molecular nitrogen cation excited in the presence of ionizing radiation. Optical emission spectra of atmospheric air and nitrogen surrounding 210Po sources were measured from 250 to 400 nm. Multi-Boltzmann and non-Boltzmann vibrational distribution spectral models were used to determine the vibrational temperature and vibrational distribution function of the emitting N2(C3Πu) and N2+(B2Σ+u) states. A zero-dimensional kinetic model, based on the electron energy distribution function (EEDF) and steady-state excitation and de-excitation of N2(X1Σ+g), N2+(B2Σ+u), N2+(X2Σ+g), N4+, O2+, and N2(C3Πu, v), was developed for the prediction of the relative spectral intensity of both the N2+(B2Σ+u → X2Σ+g) emission band and the vibrational bands of N2(C3Πu → B3Πg) for comparison with the experimental data.

4.
BMC Health Serv Res ; 24(1): 343, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491374

RESUMO

BACKGROUND: Critical care nurses (CCNs) are routinely exposed to highly stressful situations, and at high-risk of suffering from work-related stress and developing burnout. Thus, supporting CCN wellbeing is crucial. One approach for delivering this support is by preparing CCNs for situations they may encounter, drawing on evidence-based techniques to strengthen psychological coping strategies. The current study tailored a Resilience-boosting psychological coaching programme [Reboot] to CCNs. Other healthcare staff receiving Reboot have reported improvements in confidence in coping with stressful clinical events and increased psychological resilience. The current study tailored Reboot for online, remote delivery to CCNs (as it had not previously been delivered to nurses, or in remote format), to (1) assess the feasibility of delivering Reboot remotely, and to (2) provide a preliminary assessment of whether Reboot could increase resilience, confidence in coping with adverse events and burnout. METHODS: A single-arm mixed-methods (questionnaires, interviews) before-after feasibility study design was used. Feasibility was measured via demand, recruitment, and retention (recruitment goal: 80 CCNs, retention goal: 70% of recruited CCNs). Potential efficacy was measured via questionnaires at five timepoints; measures included confidence in coping with adverse events (Confidence scale), Resilience (Brief Resilience Scale), depression (PHQ-9) and burnout (Oldenburg-Burnout-Inventory). Intention to leave (current role, nursing more generally) was measured post-intervention. Interviews were analysed using Reflexive Thematic Analysis. RESULTS: Results suggest that delivering Reboot remotely is feasible and acceptable. Seventy-seven nurses were recruited, 81% of whom completed the 8-week intervention. Thus, the retention rate was over 10% higher than the target. Regarding preliminary efficacy, follow-up measures showed significant increases in resilience, confidence in coping with adverse events and reductions in depression, burnout, and intention to leave. Qualitative analysis suggested that CCNs found the psychological techniques helpful and particularly valued practical exercises that could be translated into everyday practice. CONCLUSION: This study demonstrates the feasibility of remote delivery of Reboot and potential efficacy for CCNs. Results are limited due to the single-arm feasibility design; thus, a larger trial with a control group is needed.


Assuntos
Esgotamento Profissional , Tutoria , Resiliência Psicológica , Humanos , Depressão , Intenção , Esgotamento Profissional/prevenção & controle , Esgotamento Profissional/psicologia , Capacidades de Enfrentamento , Cuidados Críticos , Inquéritos e Questionários
5.
Opt Express ; 30(17): 30822-30831, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-36242179

RESUMO

We demonstrate a hermetically sealed packaging system for integrated photonic devices at cryogenic temperatures with plug-and-play functionality. This approach provides the ability to encapsulate a controlled amount of gas into the optical package allowing helium to be used as a heat-exchange gas to thermalize photonic devices, or condensed into a superfluid covering the device. This packaging system was tested using a silicon-on-insulator slot waveguide resonator which fills with superfluid 4He below the transition temperature. To optimize the fiber-to-chip optical integration 690 tests were performed by thermally cycling optical fibers bonded to various common photonic chip substrates (silicon, silicon oxide and HSQ) with a range of glues (NOA 61, NOA 68, NOA 88, NOA 86H and superglue). This showed that NOA 86H (a UV curing optical adhesive with a latent heat catalyst) provided the best performance under cryogenic conditions for all the substrates tested. The technique is relevant to superfluid optomechanics experiments, as well as quantum photonics and quantum optomechanics applications.

6.
J Surg Oncol ; 126(2): 356-364, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35319106

RESUMO

BACKGROUND: Little is known about the drivers of readmission in patients undergoing Orthopaedic oncologic resection. The goal of this study was to identify factors independently associated with 90-day readmission for patients undergoing oncologic resection and subsequent prosthetic reconstruction for primary tumors involving bone. METHODS: This was a retrospective comparative cohort study of patients treated from 2008 to 2019 who underwent endoprosthetic reconstruction for a primary bone tumor or soft tissue tumor involving bone, as well as those who underwent a revision endoprosthetic reconstruction if the primary endoprosthetic reconstruction was performed for an oncologic resection. The primary outcome measure was unplanned 90-day readmission. RESULTS: A total of 149 patients were identified who underwent 191 surgeries were for a primary bone or soft tissue tumor. The 90-day readmission rate was 28.3%. Female gender, depression, higher tumor grade, vascular reconstruction, longer procedure duration, longer length of stay (LOS), multiple surgeries during an admission and disposition to a Skilled Nursing Facility were associated with readmission (p < 0.05). In a multivariate analysis, female sex, higher tumor grade and longer procedure duration were independently associated with risk of readmission (p < 0.05). CONCLUSIONS: Readmission rates are high following endoprosthetic reconstruction for Orthopaedic oncologic resections. Further work is necessary to help minimize unplanned readmissions.


Assuntos
Neoplasias Ósseas , Sarcoma , Neoplasias de Tecidos Moles , Neoplasias Ósseas/patologia , Neoplasias Ósseas/cirurgia , Estudos de Coortes , Feminino , Humanos , Readmissão do Paciente , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos , Fatores de Risco , Sarcoma/cirurgia , Neoplasias de Tecidos Moles/cirurgia
7.
J Arthroplasty ; 37(2): 232-237, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34740789

RESUMO

BACKGROUND: Orthopedic oncology patients are particularly susceptible to increased readmission rates and poor surgical outcomes, yet little is known about readmission rates. The goal of this study is to identify factors independently associated with 90-day readmission for patients undergoing oncologic resection and subsequent prosthetic reconstruction for metastatic disease of the hip and knee. METHODS: This is a retrospective comparative cohort study of all patients treated from 2013 to 2019 at a single tertiary care referral institution who underwent endoprosthetic reconstruction by an orthopedic oncologist for metastatic disease of the extremities. The primary outcome measure was unplanned 90-day readmission. RESULTS: We identified 112 patients undergoing 127 endoprosthetic reconstruction surgeries. Metastatic disease was most commonly from renal (26.8%), lung (23.6%), and breast (13.4%) cancer. The most common type of skeletal reconstruction performed was simple arthroplasty (54%). There were 43 readmissions overall (33.9%). When controlling for confounding factors, body mass index >40, insurance status, peripheral vascular disease, and longer hospital length of stay were independently associated with risk of readmission (P ≤ .05). CONCLUSION: Readmission rates for endoprosthetic reconstructions for metastatic disease are high. Although predicting readmission remains challenging, risk stratification presents a viable option for helping minimize unplanned readmissions. LEVEL OF EVIDENCE: III.


Assuntos
Neoplasias , Readmissão do Paciente , Estudos de Coortes , Humanos , Extremidade Inferior , Neoplasias/epidemiologia , Neoplasias/cirurgia , Complicações Pós-Operatórias , Estudos Retrospectivos , Fatores de Risco
8.
J Ment Health ; 31(3): 392-401, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34643159

RESUMO

OBJECTIVES: To conduct a 1-year evaluation of James' Place, a suicidal crisis centre delivering a clinical intervention in a community setting. DESIGN: A case series study, following men entering the service during the first year of operation. PARTICIPANTS: Men experiencing a suicidal crisis referred to the service (N = 265), with N = 176 going on to engage in therapy. INTERVENTION: The James' Place Model is a therapeutic intervention offered to men who are in a suicidal crisis. Trained therapists provide a range of therapeutic approaches and interventions, focusing on decreasing suicidal distress and supporting men to develop resilience and coping strategies. MAIN OUTCOME MEASURES: CORE-34 Clinical Outcome Measure (CORE-OM). RESULTS: For all subscales of the CORE-OM there was a significant reduction in mean scores between assessment and discharge (p < 0.001), with all outcomes demonstrating a large effect size. All reductions illustrated a clinically significant change or a reliable change. CONCLUSIONS: Our results support the use of the James' Place Model for men in suicidal distress to aid in potentially preventing suicides in this high-risk group of the population.HighlightsEvaluates a brief psychological clinical intervention delivered in the community.Model effectively reduces suicide risk and findings can inform future services.Accessed men receiving an innovative intervention at the time of suicidal crisis.


Assuntos
Ideação Suicida , Prevenção do Suicídio , Suicídio , Intervenção em Crise , Humanos , Masculino , Modelos Psicológicos , Intervenção Psicossocial , Suicídio/psicologia
9.
Am J Transplant ; 21(2): 582-592, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32741100

RESUMO

Vascularized composite allografts (VCAs) can restore fully functional anatomic units in patients with limb amputations or severe facial tissue loss. However, acute rejection of the skin is frequently observed and underscores the importance of developing tolerance induction protocols. In this study, we have characterized the skin immune system in VCAs. We demonstrate infiltration of recipient leukocytes, regardless of rejection status, and in tolerant mixed hematopoietic chimeras, the co-existence of these cells with donor leukocytes in the absence of rejection. Here we characterize the dermal T cell and epidermal Langerhans cell components of the skin immune system in our porcine model of VCA tolerance, and the kinetics of cutaneous chimerism in both of these populations in VCAs transplanted to tolerant and nontolerant recipients, as well as in host skin. Furthermore, in biopsies from the first patient to receive a hand transplant in our program, we demonstrate the presence of recipient T cells in the skin of the transplanted limb in the absence of clinical or histological evidence of rejection.


Assuntos
Aloenxertos Compostos , Animais , Rejeição de Enxerto/etiologia , Sobrevivência de Enxerto , Humanos , Leucócitos , Suínos , Quimeras de Transplante
10.
J Trauma Stress ; 34(6): 1228-1237, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33650171

RESUMO

Individuals with posttraumatic stress disorder (PTSD) are at increased risk for suicidal thoughts and behaviors; however, clinicians often report apprehension about recommending trauma-focused therapy to patients with an increased risk of suicide. The present study aimed to evaluate the safety, tolerability, and response to cognitive processing therapy (CPT) among a sample of military veterans with PTSD and increased suicide risk. A secondary aim was to provide a clinically useful definition of high suicide risk. Chart review was used to classify the suicide risk level of 290 veterans who participated in CPT at a Veterans Affairs clinic. Treatment outcomes in veterans with different suicide risk levels were also gathered and compared. Over 50% (n = 155) of the sample demonstrated increased suicide risk, and 1.0% (n = 3) engaged in suicidal behavior after initiating treatment. To date, hospital records show no suicide deaths since 2016 among clinic patients who received CPT. Suicide risk level was not associated with CPT tolerability, and PTSD symptom change was equivalent across groups, ps = .085-.976. Veterans across groups reported clinically significant reductions in PTSD symptoms. The tested suicide risk categorization schemes performed similarly in differentiating the odds of CPT completion and PTSD symptom reduction. These results suggest that veterans with PTSD and an increased risk of suicide, including those with previous suicide attempts and current ideation, can tolerate and benefit from CPT. Additional variables must be considered to truly determine the acute and imminent suicide risk that would deem CPT to be contraindicated.


Assuntos
Terapia Cognitivo-Comportamental , Transtornos de Estresse Pós-Traumáticos , Veteranos , Terapia Cognitivo-Comportamental/métodos , Humanos , Transtornos de Estresse Pós-Traumáticos/psicologia , Transtornos de Estresse Pós-Traumáticos/terapia , Ideação Suicida , Tentativa de Suicídio , Veteranos/psicologia
11.
Int J Biometeorol ; 65(1): 45-58, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32666310

RESUMO

The atmosphere is host to a complex electric environment, ranging from a global electric circuit generating fluctuating atmospheric electric fields to local lightning strikes and ions. While research on interactions of organisms with their electrical environment is deeply rooted in the aquatic environment, it has hitherto been confined to interactions with local electrical phenomena and organismal perception of electric fields. However, there is emerging evidence of coupling between large- and small-scale atmospheric electrical phenomena and various biological processes in terrestrial environments that even appear to be tied to continental waters. Here, we synthesize our current understanding of this connectivity, discussing how atmospheric electricity can affect various levels of biological organization across multiple ecosystems. We identify opportunities for research, highlighting its complexity and interdisciplinary nature and draw attention to both conceptual and technical challenges lying ahead of our future understanding of the relationship between atmospheric electricity and the organization and functioning of biological systems.


Assuntos
Ecossistema , Eletricidade , Atmosfera
12.
J Shoulder Elbow Surg ; 30(11): e647-e658, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34273534

RESUMO

BACKGROUND: In recent years, there has been growing interest in the use of reverse total shoulder arthroplasty (rTSA) for reconstruction of the proximal humerus after oncologic resection. However, the indications and outcomes of oncologic rTSA remain unclear. METHODS: We conducted a systematic review to identify studies that reported outcomes of patients who underwent rTSA for oncologic reconstruction of the proximal humerus. Extracted data included demographic characteristics, indications, operative techniques, outcomes, and complications. Weighted means were calculated according to sample size. RESULTS: Twelve studies were included, containing 194 patients who underwent rTSA for oncologic reconstruction of the proximal humerus. The mean patient age was 48 years, and 52% of patients were male. Primary malignancies were present in 55% of patients; metastatic disease, 30%; and benign tumors, 9%. The mean humeral resection length was 12 cm. The mean postoperative Musculoskeletal Tumor Society score was 78%; Constant score, 60; and Toronto Extremity Salvage Score, 77%. The mean complication rate was 28%, with shoulder instability accounting for 63% of complications. Revisions were performed in 16% of patients, and the mean implant survival rate was 89% at a mean follow-up across studies of 53 months. CONCLUSIONS: Although the existing literature is of poor study quality, with a high level of heterogeneity and risk of bias, rTSA appears to be a suitable option in appropriately selected patients undergoing oncologic resection and reconstruction of the proximal humerus. The most common complication is instability. Higher-quality evidence is needed to help guide decision making on appropriate implant utilization for patients undergoing oncologic resection of the proximal humerus.


Assuntos
Artroplastia do Ombro , Instabilidade Articular , Articulação do Ombro , Humanos , Úmero/cirurgia , Instabilidade Articular/cirurgia , Masculino , Pessoa de Meia-Idade , Amplitude de Movimento Articular , Estudos Retrospectivos , Ombro , Articulação do Ombro/cirurgia , Resultado do Tratamento
13.
J Infect Dis ; 222(8): 1371-1382, 2020 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-32496543

RESUMO

BACKGROUND: An antigenic mismatch between the vaccine and circulating H3N2 strains was hypothesized to contribute to the severity of the 2017-2018 season in North America. METHODS: Serum and nasal washes were collected from influenza positive and negative patients during the 2017-2018 season to determine neutralizing antibody (nAb) titers and for influenza virus sequencing, respectively. RESULTS: The circulating and vaccine H3N2 virus strains were different clades, with the vaccine strain being clade 3C.2a and the circulating viruses being 3C.2a2 or 3C.3a. At enrollment, both the H3N2 negative and positive patients had greater nAb titers to the egg-adapted vaccine virus compared to the cell-grown vaccine but the H3N2-negative population had significantly greater titers to the circulating 3C.2a2. Among H3N2-positive patients, vaccination, younger age, and female sex were associated with greater nAb responses to the egg-adapted vaccine H3N2 virus but not to the cell-grown vaccine or circulating viruses. CONCLUSIONS: For the 2017-2018 circulating viruses, mutations introduced by egg adaptation decreased vaccine efficacy. No increased protection was afforded by vaccination, younger age, or female sex against 2017-2018 circulating H3N2 viruses.


Assuntos
Anticorpos Neutralizantes/imunologia , Vírus da Influenza A Subtipo H3N2/imunologia , Vacinas contra Influenza/imunologia , Influenza Humana/epidemiologia , Adolescente , Adulto , Idoso , Anticorpos Neutralizantes/sangue , Feminino , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/imunologia , Humanos , Vírus da Influenza A Subtipo H3N2/genética , Vacinas contra Influenza/administração & dosagem , Vacinas contra Influenza/genética , Influenza Humana/prevenção & controle , Influenza Humana/virologia , Masculino , Pessoa de Meia-Idade , Mutação , Fatores Sexuais , Estados Unidos/epidemiologia , Vacinação , Adulto Jovem
14.
Phys Rev Lett ; 124(19): 198701, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32469542

RESUMO

Rainfall is hypothesized to be influenced by droplet charge, which is related to the global circuit current flowing through clouds. This is tested through examining a major global circuit current increase following the release of artificial radioactivity. Significant changes occurred in daily rainfall distribution in the Shetland Islands, away from pollution. Daily rainfall changed by 24%, and local clouds optically thickened, within the nuclear weapons test period. This supports expectations of electrically induced microphysical changes in liquid water clouds from additional ionization.

15.
BMC Infect Dis ; 20(1): 734, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33028245

RESUMO

BACKGROUND: HIV continues to be the main determinant morbidity with high mortality rates in Sub-Saharan Africa, with a high number of patients being late presenters with advanced HIV. Clinical management of advanced HIV patients is thus complex and requires strict adherence to updated, empirical and simplified guidelines. The current study investigated the impact of the implementation of a new clinical guideline on the management of advanced HIV in Kinshasa, Democratic Republic of Congo (DRC). METHODS: A retrospective analysis of routine clinical data of advanced HIV patients was conducted for the periods; February 2016 to March 2017, before implementation of new guidelines, and November 2017 to July 2018, after the implementation of new guidelines. Eligible patients were patients with CD4 < 200 cell/µl and presenting with at least 1 of 4 opportunistic infections. Patient files were reviewed by a medical doctor and a committee of 3 other doctors for congruence. Statistical significance was set at 0.05%. RESULTS: Two hundred four and Two hundred thirty-one patients were eligible for inclusion before and after the implementation of new guidelines respectively. Sex and age distributions were similar for both periods, and median CD4 were 36 & 52 cell/µl, before and after the new guidelines implementation, respectively. 40.7% of patients had at least 1 missed/incorrect diagnosis before the new guidelines compared to 30% after new guidelines, p < 0.05. Clinical diagnosis for TB and toxoplasmosis were also much improved after the implementation of new guidelines. In addition, only 63% of patients had CD4 count test results before the new guidelines compared to 99% of patients after new guidelines. Death odds after the implementation of new guidelines were significantly lower than before new guidelines in a multivariate regression model that included patients CD4 count and 10 other covariates, p < 0.05. CONCLUSIONS: Simplification and implementation of a new and improved HIV clinical guideline coupled with the installation of laboratory equipment and point of care tests potentially helped reduce incorrect diagnosis and improve clinical outcomes of patients with advanced HIV. Regulating authorities should consider developing simplified versions of guidelines followed by the provision of basic diagnostic equipment to health centers.


Assuntos
Antirretrovirais/uso terapêutico , Infecções por HIV/tratamento farmacológico , Adolescente , Adulto , Instituições de Assistência Ambulatorial , Contagem de Linfócito CD4 , República Democrática do Congo , Feminino , Guias como Assunto , Infecções por HIV/complicações , Infecções por HIV/mortalidade , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Toxoplasmose/complicações , Toxoplasmose/diagnóstico , Tuberculose/complicações , Tuberculose/diagnóstico , Adulto Jovem
16.
Public Health ; 178: 105-111, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31669907

RESUMO

BACKGROUND: The purpose of this article is to identify and describe key components of research into the teaching methods of public health to postgraduate students. STUDY DESIGN: This is a systematic review of the published literature. METHODS: A detailed search of the literature based on keywords, Boolean operators, and free-text terms, identified from PubMed, Scopus and ERIC, published in the English language, between January 2000 and December 2017, was made. Teams of independent pairs agreed studies eligible for the review and performed data extraction. RESULTS: Of the 2,442 potential studies on education of public health professionals, 86 met all the inclusion criteria. Specific study designs, data collection, and techniques for data analysis varied widely across the individual studies, and there was a lack of consistency on the whole. The number of students in each study ranged from ten to 1,300. Forty-seven studies used quantitative methods to assess the effectiveness of teaching. Curriculum evaluation was the most common focus (n = 33), followed by course evaluation (n = 22). Few studies considered inequalities in terms of the types of students registered on the different courses/programs, with just three evaluating strategies to increase students from minority ethnic groups. Most studies evaluated short-term or medium-term outcomes rather than long-term impacts of education on students' careers or the relationship of education in meeting future public health workforce demands. CONCLUSIONS: This comprehensive systematic review identified a dearth of the literature on evaluations of approaches for teaching public health to health professions students. Those studies that had been published varied to such an extent in terms of their aims, methods, analysis, and results such that it was impossible to make any consistent comparisons of the observations reported in the studies. We conclude that evidence-based approaches for teaching public health to health professions students are either not sought by faculty and programs or, if conducted, not shared. As such, there are likely to be missed opportunities for ensuring that future graduates of health professions programs are as well prepared as possible to contribute to the health of the public.


Assuntos
Ocupações em Saúde/educação , Saúde Pública/educação , Currículo , Educação de Pós-Graduação/organização & administração , Humanos , Estudantes de Ciências da Saúde , Ensino
17.
Inorg Chem ; 58(5): 2930-2933, 2019 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-30776219

RESUMO

A unique class of enantiopure N-heterocyclic carbene half-sandwich iridium complexes is reported. These compounds display stable configurations at the metal center, as demonstrated by their chiroptical properties. Remarkably, because of the nature of the naphthalimide molecule, two regioisomers containing five-membered [( R)-2a and ( S)-2a] and six-membered [( R)-2b and ( S)-2b] iridacycles were obtained. Density functional theory calculations are advanced to rationalize their relative stability.

18.
Nature ; 504(7478): 119-21, 2013 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-24305162

RESUMO

After the initial burst of γ-rays that defines a γ-ray burst (GRB), expanding ejecta collide with the circumburst medium and begin to decelerate at the onset of the afterglow, during which a forward shock travels outwards and a reverse shock propagates backwards into the oncoming collimated flow, or 'jet'. Light from the reverse shock should be highly polarized if the jet's magnetic field is globally ordered and advected from the central engine, with a position angle that is predicted to remain stable in magnetized baryonic jet models or vary randomly with time if the field is produced locally by plasma or magnetohydrodynamic instabilities. Degrees of linear polarization of P ≈ 10 per cent in the optical band have previously been detected in the early afterglow, but the lack of temporal measurements prevented definitive tests of competing jet models. Hours to days after the γ-ray burst, polarization levels are low (P < 4 per cent), when emission from the shocked ambient medium dominates. Here we report the detection of P =28(+4)(-4) per cent in the immediate afterglow of Swift γ-ray burst GRB 120308A, four minutes after its discovery in the γ-ray band, decreasing to P = 16(+5)(-4) per cent over the subsequent ten minutes. The polarization position angle remains stable, changing by no more than 15 degrees over this time, with a possible trend suggesting gradual rotation and ruling out plasma or magnetohydrodynamic instabilities. Instead, the polarization properties show that GRBs contain magnetized baryonic jets with large-scale uniform fields that can survive long after the initial explosion.

19.
Eur J Appl Physiol ; 119(11-12): 2599-2608, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31598781

RESUMO

PURPOSE: This study examined the effects of a novel maltodextrin-fructose hydrogel supplement (MF-H) on cycling performance and gastrointestinal distress symptoms. METHODS: Nine endurance-trained male cyclists (age = 26.1 ± 6.6, mass = 80.9 ± 10.4 kg, VO2max = 55.5 ± 3.6 mL·kg·min-1) completed three experimental trials consisting of a 98-min varied-intensity cycling protocol followed by a performance test of ten consecutive sprint intervals. In a cross-over design, subjects consumed 250 mL of a treatment beverage every 15 min of cycling. Treatments consisted of 78 g·hr-1 of either (a) MF-H, (b) isocaloric maltodextrin-fructose (ratio-matched 2:1; MF), and (c) isocaloric maltodextrin only (MD). RESULTS: There were no differences in average sprint power between treatments (MF-H, 284 ± 51 W; MF, 281 ± 46 W; and MD, 277 ± 48 W), or power output for any individual sprint. Subjective ratings of gastrointestinal distress symptoms (nausea, fullness, and abdominal cramping) increased significantly over time during the cycling trials, but few individuals exceeded moderate levels in any trial with no systematic differences in gastrointestinal discomfort symptoms observed between treatments. CONCLUSIONS: In conclusion, ingestion of a maltodextrin/fructose hydrogel beverage during high-intensity cycling does not improve gastrointestinal comfort or performance compared to MF or MD beverages.


Assuntos
Desempenho Atlético/fisiologia , Ciclismo/fisiologia , Carboidratos da Dieta/administração & dosagem , Hidrogéis/administração & dosagem , Resistência Física/efeitos dos fármacos , Adulto , Bebidas , Estudos Cross-Over , Suplementos Nutricionais , Frutose/administração & dosagem , Humanos , Masculino , Resistência Física/fisiologia
20.
J Radiol Prot ; 39(4): R37-R50, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31307030

RESUMO

This paper provides a summary of the Education and Training (E&T) activities that have been developed and organised by the European Radiation Dosimetry Group (EURADOS) in recent years and in the case of Training Courses over the last decade. These E&T actions include short duration Training Courses on well-established topics organised within the activity of EURADOS Working Groups (WGs), or one-day events integrated in the EURADOS Annual Meeting (workshops, winter schools, the intercomparison participants' sessions and the learning network, among others). Moreover, EURADOS has recently established a Young Scientist Grant and a Young Scientist Award. The Grant supports young scientists by encouraging them to perform research projects at other laboratories of the EURADOS network. The Award is given in recognition of excellent work developed within the WGs' work programme. Additionally, EURADOS supports the dissemination of knowledge in radiation dosimetry by promoting and endorsing conferences such as the individual monitoring (IM) series, the neutron and ion dosimetry symposia (NEUDOS) and contributions to E&T sessions at specific events.

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