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1.
Rev Sci Instrum ; 95(9)2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39240152

RESUMO

Neutron time-of-flight (nTOF) detectors are crucial in diagnosing the performance of inertial confinement fusion (ICF) experiments, which implode targets of deuterium-tritium fuel to achieve thermonuclear conditions. These detectors utilize the fusion neutron energy spectrum to extract key measurements, including the hotspot ion temperature and fuel areal density. Previous work [Danly et al., Rev. Sci. Instrum. 94, 043502 (2023)] has demonstrated adding 1D spatial resolution to an nTOF-like detector using a neutron aperture and streak camera to measure the ion temperature profile of an ICF implosion. By contrast, the study presented herein explores modifying the 1D detector to use a fast photomultiplier tube (PMT) to validate the design of a 2D spatially resolved instrument based on reconstruction from 1D profiles. The modification would collect time-of-flight traces from separate scintillators in an imaging array with one PMT using optical fibers of varying lengths to time-multiplex the signals. This technique has been demonstrated in ride-along experiments on the OMEGA laser with 20 fiber-coupled scintillator channels connected to a Photek PMT210. Results provide constraints on the fiber lengths and PMT gating requirements to promote pulse fidelity throughout all channels. Calibration of the detector to fixed nTOFs can provide a preliminary estimate of the instrument response function (IRF), although measurement of the IRF is currently under way. These results suggest that nTOF signals can potentially be time-multiplexed with fibers so long as the design is strategic to mitigate signal-to-noise reduction, modal dispersion, and charge build-up in the PMT, which has implications beyond ion temperature imaging.

2.
Rev Sci Instrum ; 95(8)2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39133088

RESUMO

Protons from the Los Alamos Neutron Science Center have been used for pulsed radiography in dynamic experiments for the past 25 years. Pulses of protons are imaged on a scintillator, and the light from these images is captured by fast gated cameras. The need for fast, bright scintillators has led to some compromises in image quality due to tiling the scintillators and backgrounds with totally internally reflected light. We show how large-grain scintillator screens, made using a thin plastic binder, solve these problems.

3.
Rev Sci Instrum ; 95(5)2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38717263

RESUMO

Neutron radiography is a technique uniquely suited to applications in nuclear diagnostics, non-destructive testing, and subcritical experiments. The spatial resolution of neutron radiographs is degraded by optical blur in the imaging system and the neutron source size, where the ideal source is point-like to optimize the point-spread function. A potential neutron source for radiography is the dense plasma focus (DPF), a coaxial Z-pinch that produces thermonuclear and beam-target neutrons. To assess if the source size is suitable for radiography, a neutron imaging system was used to measure the source size of the 4 MA Sodium DPF at the Nevada National Security Site operating with deuterium-tritium gas-fill. The source size was measured using the edge-spread function of tungsten objects, each having a rolled (convex) edge. The spot size was found to be 7-12 mm full-width at half-max (FWHM) assuming a Gaussian source, though comparison is presented for Lorentzian and Bennett distributions. The average FWHM was found to be 8.6 ± 1.2 mm vertically and 10.8 ± 1.2 mm horizontally with respect to the image plane, averaging over varied edges and alignments. The results were sensitive to source alignment and edge metrology, which introduced notable uncertainties. These results are consistent with separate experimental measurements as well as magnetohydrodynamics simulations of this DPF, which suggest that neutron production can originate from pinches ∼5-7 mm off-axis. These results suggest that the DPF should be used for radiography at low magnification (M < 1) where spot size does not dominate spatial blur.

4.
Science ; 383(6687): 1062-1064, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38452091

RESUMO

As people get richer, and ecosystem services scarcer, policy-relevant estimates of ecosystem value must rise.


Assuntos
Ecossistema , Política Ambiental , Humanos , Conservação dos Recursos Naturais , Política Ambiental/economia , Análise Custo-Benefício
5.
Phys Rev E ; 109(2-2): 025203, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38491694

RESUMO

An indirect-drive inertial fusion experiment on the National Ignition Facility was driven using 2.05 MJ of laser light at a wavelength of 351 nm and produced 3.1±0.16 MJ of total fusion yield, producing a target gain G=1.5±0.1 exceeding unity for the first time in a laboratory experiment [Phys. Rev. E 109, 025204 (2024)10.1103/PhysRevE.109.025204]. Herein we describe the experimental evidence for the increased drive on the capsule using additional laser energy and control over known degradation mechanisms, which are critical to achieving high performance. Improved fuel compression relative to previous megajoule-yield experiments is observed. Novel signatures of the ignition and burn propagation to high yield can now be studied in the laboratory for the first time.

6.
RSC Chem Biol ; 4(10): 804-816, 2023 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-37799586

RESUMO

Amide peptide backbone methylation is a characteristic post-translational modification found in a family of ribosomally synthesized and post-translationally modified peptide natural products (RiPPs) called borosins. Previously, we bioinformatically identified >1500 putative borosin pathways in bacteria; however, none of the pathways were associated with a known secondary metabolite. Through in-depth characterization of a borosin pathway in Shewanella oneidensis MR-1, we have now identified a bacterially derived borosin natural product named Shewanellamide A. Borosin identification was facilitated by the creation and analysis of a series of precursor variants and crystallographic interrogation of variant precursor and methyltransferase complexes. Along with assaying two proteases from S. oneidensis, probable boundaries for proteolytic maturation of the metabolite were projected and confirmed via comparison of S. oneidensis knockout and overexpression strains. All in all, the S. oneidensis natural product was found to be a 16-mer linear peptide featuring two backbone methylations, establishing Shewanellamide A as one of the few borosin metabolites yet identified, and the first from bacteria.

7.
Res Child Adolesc Psychopathol ; 51(12): 1933-1944, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37875642

RESUMO

Despite the five million children in the U.S. with an incarcerated parent, there is limited research on risk and protective factors for this population. We analyzed data from the National Survey for Children's Health (2018) to: (1) examine associations among parental incarceration and other adverse childhood experiences (ACEs), (2) characterize the association between parental incarceration and youth mental health outcomes, (3) examine differences in positive childhood experiences (PCEs; collective socialization, community engagement, neighborhood amenities, and family problem solving) by parental incarceration status, (4) examine whether PCEs were protective against mental health problems and if there was an interaction with parental incarceration status, and (5) examine the interaction between PCEs, parental incarceration, and ACEs on mental health problems. Results revealed that children with incarcerated parents had higher odds of experiencing other ACEs, higher odds of having mental health problems, and experienced fewer PCEs compared to children without incarcerated parents. Further, although PCEs were associated with a lower odds of mental health problems for both children with and without incarcerated parents, they did not mitigate the negative impact of parental incarceration on mental health outcomes. While PCEs attenuated the association between ACEs and mental health, parental incarceration status did not significantly moderate the interaction. These results highlight vulnerabilities and potential protective factors for children with incarcerated parents and have important implications for the development of multilevel intervention strategies that seek to promote resilience and reduce risk for this population.


Assuntos
Experiências Adversas da Infância , Criança , Adolescente , Humanos , Pais/psicologia , Saúde Mental , Socialização , Estabelecimentos Correcionais
8.
Int J Dev Disabil ; 69(5): 644-653, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37547550

RESUMO

Background: Individuals with neurodevelopmental disorders (NDD) are facing unprecedented challenges due to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic. Congregate living, and conditions associated with NDD place increased challenges during infectious disease outbreaks and there is a need to understand evidence-based response procedures. The aim was to (1) map and synthesize literature regarding emergency response protocol in supported living environments for individuals with NDD and (2) identify gaps in the literature of response protocols in supported living environments for individuals with NDD. Methods: A scoping review was conducted to understand the published literature on emergency response across supported living environments for individuals with NDD during emergency situations and infectious disease outbreaks. Results: The ten studies included in the review detailed protocols including treatment, testing, isolation, surveillance, improved cleaning, use of protective equipment, and contact with public health professionals. The environment of supported living settings, and symptoms associated with NDD impacted the spread and severity of disease. Conclusion: The research findings highlight the susceptibility, severity and impact of infectious disease outbreaks for individuals with NDD in supported living environments. This research will promote the establishment and development of appropriate care and response during emergency situations in supported living environments.

9.
Phys Rev Lett ; 131(6): 065101, 2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37625041

RESUMO

The change in the power balance, temporal dynamics, emission weighted size, temperature, mass, and areal density of inertially confined fusion plasmas have been quantified for experiments that reach target gains up to 0.72. It is observed that as the target gain rises, increased rates of self-heating initially overcome expansion power losses. This leads to reacting plasmas that reach peak fusion production at later times with increased size, temperature, mass and with lower emission weighted areal densities. Analytic models are consistent with the observations and inferences for how these quantities evolve as the rate of fusion self-heating, fusion yield, and target gain increase. At peak fusion production, it is found that as temperatures and target gains rise, the expansion power loss increases to a near constant ratio of the fusion self-heating power. This is consistent with models that indicate that the expansion losses dominate the dynamics in this regime.

10.
J Intellect Disabil Res ; 67(4): 375-386, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36744441

RESUMO

BACKGROUND: It appears that students with intellectual disability (ID) are more frequently absent from school compared with students without ID. The objective of the current study was to estimate the frequency of absence among students with ID and the reasons for absence. Potential reasons included the attendance problems referred to as school refusal, where absence is related to emotional distress; truancy, where absence is concealed from parents; school exclusion, where absence is instigated by the school; and school withdrawal, where absence is initiated by parents. METHODS: Study participants were 629 parents (84.6% mothers) of Australian school students (Mage  = 11.18 years; 1.8% Aboriginal and/or Torres Strait Islander) with an ID. Participants completed a questionnaire battery that included the School Non-Attendance ChecKlist via which parents indicated the reason their child was absent for each day or half-day absence their child had over the past 20 school days. The absence data presented to parents had been retrieved from school records. RESULTS: Across all students, absence occurred on 7.9% of the past 20 school days. In terms of school attendance problems as defined in existing literature, school withdrawal accounted for 11.1% of absences and school refusal for 5.3% of absences. Students were also absent for other reasons, most commonly illness (32.0%) and appointments (24.2%). Of students with more than one absence (n = 217; 34.5%), about half were absent for more than one reason. Students attending mainstream schools had lower attendance than those attending special schools. CONCLUSIONS: Students with ID were absent for a range of reasons and often for multiple reasons. There were elevated rates of school withdrawal and school refusal. Understanding the reasons for absenteeism can inform targeted prevention and intervention supports.


Assuntos
Absenteísmo , Deficiência Intelectual , Criança , Feminino , Humanos , Deficiência Intelectual/epidemiologia , Austrália/epidemiologia , Estudantes/psicologia , Pais
11.
Sci Rep ; 13(1): 2227, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36755138

RESUMO

Contact and projection electron radiography of static targets was demonstrated using a laser-plasma accelerator driven by a kilojoule, picosecond-class laser as a source of relativistic electrons with an average energy of 20 MeV. Objects with areal densities as high as 7.7 g/cm2 were probed in materials ranging from plastic to tungsten, and radiographs with resolution as good as 90 µm were produced. The effects of electric fields produced by the laser ablation of the radiography objects were observed and are well described by an analytic expression relating imaging magnification change to electric-field strength.

12.
Rev Sci Instrum ; 93(4): 043901, 2022 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-35489888

RESUMO

We describe the use of a coplanar waveguide (CPW) whose slots are filled with a resistive film, a resistively loaded CPW (RLCPW), to measure two-dimensional electron systems (2DESs). The RLCPW applied to the sample hosting the 2DES provides a uniform metallic surface serving as a gate to control the areal charge density of the 2DES. As a demonstration of this technique, we present measurements on a Si metal-oxide-semiconductor field-effect transistor and a model that successfully converts microwave transmission coefficients into conductivity of a nearby 2DES capacitively coupled to the RLCPW. We also describe the process of fabricating the highly resistive metal film required for fabrication of the RLCPW.

13.
Phys Rev Lett ; 129(27): 275001, 2022 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-36638294

RESUMO

We present measurements of ice-ablator mix at stagnation of inertially confined, cryogenically layered capsule implosions. An ice layer thickness scan with layers significantly thinner than used in ignition experiments enables us to investigate mix near the inner ablator interface. Our experiments reveal for the first time that the majority of atomically mixed ablator material is "dark" mix. It is seeded by the ice-ablator interface instability and located in the relatively cooler, denser region of the fuel assembly surrounding the fusion hot spot. The amount of dark mix is an important quantity as it is thought to affect both fusion fuel compression and burn propagation when it turns into hot mix as the burn wave propagates through the initially colder fuel region surrounding an igniting hot spot. We demonstrate a significant reduction in ice-ablator mix in the hot-spot boundary region when we increase the initial ice layer thickness.

14.
Facial Plast Surg ; 38(3): 260-273, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-34891180

RESUMO

The techniques presented in article will allow the facial plastic specialist to use the anatomy of each individual patient as a guide for the surgical release of the brow performed during endoscopic brow lift. The author presents his 15 years of experience in which he developed this approach. Five different surgical releases of the brow will be demonstrated and discussed in terms of which patients would best benefit from which release. Adopting this approach has made the predictability of the authors brow lift results much better and therefore improved patient satisfaction. This concept has not been described in the literature and the author firmly believes using a preoperative anatomical approach is a better way to approach endoscopic brow lift surgery.


Assuntos
Ritidoplastia , Endoscopia/métodos , Sobrancelhas , Testa/cirurgia , Humanos , Masculino , Satisfação do Paciente , Estudos Retrospectivos , Ritidoplastia/métodos
15.
Forensic Sci Int ; 327: 110962, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34474199

RESUMO

INTRODUCTION: Most findings of forensic pathology examinations are presented as written reports. There are currently no internationally accepted recommendations for writing forensic pathology reports. Existing recommendations are also varied and reflect the differences in the scope and role of forensic medical services and local settings in which they are to be implemented. The legal fact-finder thus faces wide variation in the quality of forensic pathology reports, which poses a threat to the reliability of legal decision-making. To address this issue, the development of the "PERFORM-P (Principles of Evidence-based Reporting in FORensic Medicine-Pathology version)" was undertaken. The goal of the PERFORM-P is to provide common practice recommendations adaptable to local requirements to promote evidence-based practice (EBP) in forensic pathology. METHODS: An international consensus study was conducted in three phases by (1) developing a long-list of items to be considered in the reporting recommendations, (2) conducting a Delphi process (an iterative survey method to transform individual opinions into group consensus) with international forensic pathologists, and (3) designing the PERFORM-P prototype and its accompanying manual. RESULTS: With assistance from 106 forensic pathologists/forensic medical practitioners from 41 countries, the PERFORM-P was developed. The PERFORM-P consists of a list of 61 items to be included in a forensic pathology report, which is accompanied by its Explanation and Elaboration (E&E) document. DISCUSSION: To prepare forensic pathology (postmortem) reports that incorporate principles of evidence-based practice, internationally accepted recommendations might be helpful. The PERFORM-P identifies recommendations for necessary elements to include in a forensic pathology report. PERFORM-P can be applied to a wide range of matters requiring forensic pathological analysis, acceptable to forensic pathologists from a representative selection of jurisdictions and medico-legal systems.


Assuntos
Consenso , Técnica Delphi , Patologia Legal/normas , Guias de Prática Clínica como Assunto/normas , Relatório de Pesquisa/normas , Adulto , Prática Clínica Baseada em Evidências , Humanos , Internacionalidade , Pessoa de Meia-Idade , Inquéritos e Questionários
16.
J Invertebr Pathol ; 175: 107453, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32798534

RESUMO

The Caribbean spiny lobster, Panulirus argus (Latreille, 1804) is a highly commercial species and comprises the largest spiny lobster fishery in the world. Although populations have declined throughout its range, there is little known regarding its diseases and pathogens. The objectives of this study were to provide illustrated and standardized methods for postmortem examination, and to describe baseline gross and microscopic pathology for P. argus. From July 2017-March 2019, a postmortem examination including comprehensive histological assessment was performed on 313 fishery-caught lobsters. Epibionts and lesions observed include branchial cirriped infestation (69%), branchial encysted nemertean worm larvae (23%), tail fan necrosis (11%), skeletal muscle necrosis (7%), antennal gland calculi (6%), branchial infarction (2%), and microsporidiosis (0.6%). This report confirms the rare prevalence of microsporidiosis in P. argus and describes nemertean worm larvae in the gill. This study also reports a condition resembling excretory calcinosis in spiny lobster. The methods and data produced by this study facilitate disease diagnosis and sustainable stock management of P. argus.


Assuntos
Pesqueiros , Palinuridae/microbiologia , Palinuridae/parasitologia , Animais , Feminino , Masculino , São Cristóvão e Névis
17.
Sci Rep ; 10(1): 13098, 2020 08 04.
Artigo em Inglês | MEDLINE | ID: mdl-32753751

RESUMO

The thermal tolerances of vertebrates are generally restricted to body temperatures below 45-47 °C, and avian and mammalian critical thermal maxima seldom exceed 46 °C. We investigated thermoregulation at high air temperatures in the red-billed quelea (Quelea quelea), an African passerine bird that occurs in flocks sometimes numbering millions of individuals. Our data reveal this species can increase its body temperature to extremely high levels: queleas exposed to air temperature > 45 °C increased body temperature to 48.0 ± 0.7 °C without any apparent ill-effect, with individual values as high as 49.1 °C. These values exceed known avian lethal limits, with tolerance of body temperature > 48 °C unprecedented among birds and mammals.


Assuntos
Temperatura Corporal , Temperatura Alta , Passeriformes/fisiologia , Termotolerância , Animais
19.
S Afr Med J ; 110(3): 188-191, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32657694

RESUMO

Health promotion - keeping people healthy - is critical to ensuring that South Africa (SA)'s National Health Insurance (NHI) services and funding will not be overwhelmed by having to service and pay for large numbers of people with avoidable disease. Although the 2019 NHI Bill mentions health promotion, its lack of emphasis and the narrow approach proposed in the Bill make it unlikely that health promotion will have significant impact on population health or reducing healthcare need. Health promotion experts submit that there is in fact huge potential for carefully planned and researched health promotion to impact on population health. The establishment of a multisectoral National Health Commission or an independent Health Promotion and Development Foundation linked directly to the NHI Fund that includes several relevant government departments and civil society and researchers is proposed. Of the NHI Fund, 2% should be dedicated specifically to promoting health and preventing illness, which must support comprehensive, multisectoral health promotion interventions that go beyond awareness raising and health education. SA's specific realities and needs, including poverty and its related behavioural impacts and health consequences, must be taken into account.


Assuntos
Promoção da Saúde , Programas Nacionais de Saúde/economia , Administração Financeira , Governo , Educação em Saúde , Humanos , Doenças não Transmissíveis/mortalidade , Doenças não Transmissíveis/prevenção & controle , África do Sul
20.
Animal ; 13(11): 2519-2526, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31218983

RESUMO

The diurnal feeding patterns of dairy cows affects the 24 h robot utilisation of pasture-based automatic milking systems (AMS). A decline in robot utilisation between 2400 and 0600 h currently occurs in pasture-based AMS, as cow feeding activity is greatly reduced during this time. Here, we investigate the effect of a temporal variation in feed quality and quantity on cow feeding behaviour between 2400 and 0600 h as a potential tool to increase voluntary cow trafficking in an AMS at night. The day was allocated into four equal feeding periods (0600 to 1200, 1200 to 1800, 1800 to 2400 and 2400 to 0600 h). Lucerne hay cubes (CP = 19.1%, water soluble carbohydrate = 3.8%) and oat, ryegrass and clover hay cubes with 20% molasses (CP = 11.8%, water soluble carbohydrate = 10.7%) were offered as the 'standard' and 'preferred' (preference determined previously) feed types, respectively. The four treatments were (1) standard feed offered ad libitum (AL) throughout 24 h; (2) as per AL, with preferred feed replacing standard feed between 2400 and 0600 h (AL + P); (3) standard feed offered at a restricted rate, with quantity varying between each feeding period (20:10:30:60%, respectively) as a proportion of the (previously) measured daily ad libitum intake (VA); (4) as per VA, with preferred feed replacing standard feed between 2400 and 0600 h (VA + P). Eight non-lactating dairy cows were used in a 4 × 4 Latin square design. During each experimental period, treatment cows were fed for 7 days, including 3 days habituation and 4 days data collection. Total daily intake was approximately 8% greater (P < 0.001) for the AL and AL + P treatments (23.1 and 22.9 kg DM/cow) as compared with the VA and VA + P treatments (21.6 and 20.9 kg DM/cow). The AL + P and VA treatments had 21% and 90% greater (P < 0.001) dry matter intake (DMI) between 2400 and 0600 h, respectively, compared with the AL treatment. In contrast, the VA + P treatment had similar DMI to the VA treatment. Our experiment shows ability to increase cow feeding activity at night by varying feed type and quantity, though it is possible that a penalty to total DMI may occur using VA. Further research is required to determine if the implementation of variable feed allocation on pasture-based AMS farms is likely to improve milking robot utilisation by increasing cow feeding activity at night.


Assuntos
Ração Animal/normas , Bovinos/fisiologia , Indústria de Laticínios/instrumentação , Ingestão de Alimentos/fisiologia , Comportamento Alimentar , Ração Animal/análise , Ração Animal/classificação , Ração Animal/provisão & distribuição , Animais , Avena , Indústria de Laticínios/métodos , Dieta/veterinária , Fazendas , Feminino , Lactação , Lolium , Medicago , Leite , Robótica , Fatores de Tempo
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