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1.
Hum Brain Mapp ; 45(11): e26754, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39046031

RESUMO

Only a small number of studies have assessed structural differences between the two hemispheres during childhood and adolescence. However, the existing findings lack consistency or are restricted to a particular brain region, a specific brain feature, or a relatively narrow age range. Here, we investigated associations between brain asymmetry and age as well as sex in one of the largest pediatric samples to date (n = 4265), aged 1-18 years, scanned at 69 sites participating in the ENIGMA (Enhancing NeuroImaging Genetics through Meta-Analysis) consortium. Our study revealed that significant brain asymmetries already exist in childhood, but their magnitude and direction depend on the brain region examined and the morphometric measurement used (cortical volume or thickness, regional surface area, or subcortical volume). With respect to effects of age, some asymmetries became weaker over time while others became stronger; sometimes they even reversed direction. With respect to sex differences, the total number of regions exhibiting significant asymmetries was larger in females than in males, while the total number of measurements indicating significant asymmetries was larger in males (as we obtained more than one measurement per cortical region). The magnitude of the significant asymmetries was also greater in males. However, effect sizes for both age effects and sex differences were small. Taken together, these findings suggest that cerebral asymmetries are an inherent organizational pattern of the brain that manifests early in life. Overall, brain asymmetry appears to be relatively stable throughout childhood and adolescence, with some differential effects in males and females.


Assuntos
Encéfalo , Imageamento por Ressonância Magnética , Caracteres Sexuais , Humanos , Adolescente , Masculino , Criança , Feminino , Pré-Escolar , Lactente , Encéfalo/diagnóstico por imagem , Encéfalo/crescimento & desenvolvimento , Encéfalo/anatomia & histologia , Fatores Etários , Desenvolvimento Infantil/fisiologia , Lateralidade Funcional/fisiologia , Desenvolvimento do Adolescente/fisiologia
2.
Public Health ; 178: 120-123, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31677418

RESUMO

BACKGROUND: Public health and environmental challenges facing the world in the 21st century, including the ageing population, increasing urbanisation, rise of non-communicable diseases and climate instability, require an interdisciplinary response. A significant proportion of the population's time is spent indoors, be it at home, school, work or in leisure time; the work of an architect can cover all of these sectors, but their role in health and well-being remains an under explored area. OBJECTIVE: This article examines the architecture profession's potential to contribute to improved health and well-being of the population through healthier buildings and places. METHODOLOGY: This short communication adopts a descriptive approach. First, it maps the remit, skills and influence of the architecture profession and applies this to a well-accepted public health model, the prevention pyramid. Second, it uses themes identified by the Royal Society for Public Health to discuss ways to improve engagement with the architecture profession as part of the wider public health workforce. RESULTS: This article finds that the remit, skills and potential influence of architects places them in a key position to improve the health and well-being of the population. Despite this, there has been relatively little engagement between public health and this profession. Much more attention to date has been on integrating the planning sector with public health. CONCLUSION: Opportunities for improved engagement exist through partnership working, incorporating health into both undergraduate and postgraduate education and continuing professional development training, building the evidence base and developing architecture and health-related policy and legislation.


Assuntos
Arquitetura , Ambiente Construído/organização & administração , Mão de Obra em Saúde , Saúde Pública , Humanos
3.
J Chem Phys ; 148(13): 134312, 2018 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-29626854

RESUMO

Time and polarization-resolved stimulated emission depletion (STED) measurements are used to investigate excited state evolution following the two-photon excitation of enhanced green fluorescent protein (EGFP). We employ a new approach for the accurate STED measurement of the hitherto unmeasured degree of hexadecapolar transition dipole moment alignment α40 present at a given excitation-depletion (pump-dump) pulse separation. Time-resolved polarized fluorescence measurements as a function of pump-dump delay reveal the time evolution of α40 to be considerably more rapid than predicted for isotropic rotational diffusion in EGFP. Additional depolarization by homo-Förster resonance energy transfer is investigated for both α20 (quadrupolar) and α40 transition dipole alignments. These results point to the utility of higher order dipole correlation measurements in the investigation of resonance energy transfer processes.


Assuntos
Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/efeitos da radiação , Fótons , Polarização de Fluorescência , Transferência Ressonante de Energia de Fluorescência , Luz , Modelos Químicos , Termodinâmica
4.
J Chem Phys ; 148(13): 134311, 2018 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-29626864

RESUMO

In this work, we present a complete theoretical description of the excited state order created by two-photon photoselection from an isotropic ground state; this encompasses both the conventionally measured quadrupolar (K = 2) and the "hidden" degree of hexadecapolar (K = 4) transition dipole alignment, their dependence on the two-photon transition tensor and emission transition dipole moment orientation. Linearly and circularly polarized two-photon absorption (TPA) and time-resolved single- and two-photon fluorescence anisotropy measurements are used to determine the structure of the transition tensor in the deprotonated form of enhanced green fluorescent protein. For excitation wavelengths between 800 nm and 900 nm, TPA is best described by a single element, almost completely diagonal, two-dimensional (planar) transition tensor whose principal axis is collinear to that of the single-photon S0 → S1 transition moment. These observations are in accordance with assignments of the near-infrared two-photon absorption band in fluorescent proteins to a vibronically enhanced S0 → S1 transition.


Assuntos
Proteínas de Fluorescência Verde/química , Proteínas de Fluorescência Verde/efeitos da radiação , Fótons , Polarização de Fluorescência , Raios Infravermelhos , Modelos Químicos
5.
Paediatr Respir Rev ; 15(4): 325-32, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24958089

RESUMO

Children in indigenous populations have substantially higher respiratory morbidity than non-indigenous children. Indigenous children have more frequent respiratory infections that are, more severe and, associated with long-term sequelae. Post-infectious sequelae such as chronic suppurative lung disease and bronchiectasis are especially prevalent among indigenous groups and have lifelong impact on lung function. Also, although estimates of asthma prevalence among indigenous children are similar to non-indigenous groups the morbidity of asthma is higher in indigenous children. To reduce the morbidity of respiratory illness, best-practice medicine is essential in addition to improving socio-economic factors, (eg household crowding), tobacco smoke exposure, and access to health care and illness prevention programs that likely contribute to these issues. Although each indigenous group may have unique health beliefs and interfaces with modern health care, a culturally sensitive and community-based comprehensive care system of preventive and long term care can improve outcomes for all these conditions. This article focuses on common respiratory conditions encountered by indigenous children living in affluent countries where data is available.


Assuntos
Pneumopatias/epidemiologia , Grupos Populacionais , Criança , Humanos , Pneumopatias/etnologia
6.
J Exp Biol ; 216(Pt 21): 3947-53, 2013 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-24133149

RESUMO

Maximal performance is an essential metric for understanding many aspects of an organism's biology, but it can be difficult to determine because a measured maximum may reflect only a peak level of effort, not a physiological limit. We used a unique opportunity provided by a frog jumping contest to evaluate the validity of existing laboratory estimates of maximum jumping performance in bullfrogs (Rana catesbeiana). We recorded video of 3124 bullfrog jumps over the course of the 4-day contest at the Calaveras County Jumping Frog Jubilee, and determined jump distance from these images and a calibration of the jump arena. Frogs were divided into two groups: 'rental' frogs collected by fair organizers and jumped by the general public, and frogs collected and jumped by experienced, 'professional' teams. A total of 58% of recorded jumps surpassed the maximum jump distance in the literature (1.295 m), and the longest jump was 2.2 m. Compared with rental frogs, professionally jumped frogs jumped farther, and the distribution of jump distances for this group was skewed towards long jumps. Calculated muscular work, historical records and the skewed distribution of jump distances all suggest that the longest jumps represent the true performance limit for this species. Using resampling, we estimated the probability of observing a given jump distance for various sample sizes, showing that large sample sizes are required to detect rare maximal jumps. These results show the importance of sample size, animal motivation and physiological conditions for accurate maximal performance estimates.


Assuntos
Locomoção , Rana catesbeiana/fisiologia , Animais , Fenômenos Biomecânicos , Metabolismo Energético , Modelos Biológicos , Motivação , Probabilidade , Ranidae , Gravação de Videoteipe
7.
Eur Arch Psychiatry Clin Neurosci ; 263(6): 485-95, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23229688

RESUMO

The nucleus basalis has not been examined in detail in severe mental illness. Several studies have demonstrated decreases in glia and glial markers in the cerebral cortex in schizophrenia, familial bipolar disorder and recurrent depression. Changes in neocortical neuron size and shape have also been reported. The nucleus basalis is a collection of large cholinergic neurons in the basal forebrain receiving information from the midbrain and limbic system, projecting to the cortex and involved with attention, learning and memory, and receives regulation from serotonergic inputs. Forty-one cases aged 41-60 years with schizophrenia or major depressive disorder with age-matched controls were collected. Formalin-fixed paraffin-embedded coronal nucleus basalis sections were histologically stained for oligodendrocyte identification with cresyl-haematoxylin counterstain, for neuroarchitecture with differentiated cresyl violet stain and astrocytes were detected by glial fibrillary acid protein immunohistochemistry. Cell density and neuroarchitecture were measured using Image Pro Plus. There were larger NB oval neuron soma in the combined schizophrenia and major depression disorder groups (p = 0.038), with no significant change between controls and schizophrenia and major depression disorder separately. There is a significant reduction in oligodendrocyte density (p = 0.038) in the nucleus basalis in schizophrenia. The ratio of gemistocytic to fibrillary astrocytes showed a greater proportion of the former in schizophrenia (18.1 %) and major depressive disorder (39.9 %) than in controls (7.9 %). These results suggest glial cell abnormalities in the nucleus basalis in schizophrenia possibly leading to cortical-limbic disturbance and subcortical dysfunction.


Assuntos
Núcleo Basal de Meynert/patologia , Neurônios/patologia , Esquizofrenia/patologia , Adulto , Análise de Variância , Núcleo Basal de Meynert/metabolismo , Núcleo Basal de Meynert/fisiopatologia , Mapeamento Encefálico , Contagem de Células , Transtorno Depressivo Maior/patologia , Feminino , Proteína Glial Fibrilar Ácida/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Neuroglia/metabolismo , Neuroglia/patologia , Neurônios/metabolismo
9.
Clin Rheumatol ; 41(7): 2197-2203, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35099673

RESUMO

There is a gap in clinical knowledge regarding associations between specific inborn errors of immunity (IEIs) and rheumatologic diseases. This study reports the frequency of rheumatologic conditions in a large cohort of patients with IEI using the USIDNET (United States Immunodeficiency Network) registry. We used the USIDNET registry to conduct the analysis. We included all IEI patients within the registry for whom a diagnosed rheumatologic disease was reported. The total number of patients with IEI in our query was 5058. Among those, 278 (5.49%) patients had a diagnosis of rheumatologic disease. This cohort included 172 (61.8%) female and 106 (38.2%) male patients. Rheumatologic complications were highest in the interferonopathies (66.6%), autoimmune lymphoproliferative syndrome (ALPS) (13.7%), and immunoglobulin G subclass deficiency (IgGSD) (11.11%). Additionally, disease patterns were noted to be different in various IEI disease groups. Inflammatory myopathies were the most common rheumatologic condition in patients with X-linked agammaglobulinemia (1.65%), Sjogren's syndrome was the most common rheumatologic disease reported in ALPS patients (6.85%), and systemic lupus erythematosus was the most common rheumatologic disease in patients with chronic mucocutaneous candidiasis (CMC) (7.41%). Rheumatoid arthritis (RA) report rate was highest in patients with IgGSD (3.70%), specific antibody deficiency (SAD) (3.66%), and ALPS (2.74%). This study reports that rheumatologic diseases are frequently observed in patients with IEI. The frequency of different rheumatologic conditions was variable based on the underlying diagnosis. Clinicians caring for patients with IEI should be vigilant to monitor for rheumatologic complications. Key Points • The rates of reported rheumatologic diseases in the USIDNET registry are different in individual IEIs. • Further studies are needed to guide clinicians for detecting rheumatologic conditions earlier in patients with IEI.


Assuntos
Agamaglobulinemia , Artrite Reumatoide , Síndromes de Imunodeficiência , Síndrome de Sjogren , Agamaglobulinemia/complicações , Artrite Reumatoide/complicações , Feminino , Humanos , Síndromes de Imunodeficiência/complicações , Síndromes de Imunodeficiência/epidemiologia , Masculino , Sistema de Registros , Síndrome de Sjogren/complicações , Síndrome de Sjogren/epidemiologia
10.
Appl Radiat Isot ; 190: 110509, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36306679

RESUMO

To determine the safety of using argon as a deuteron beam stopping material, the  40Ar(d,p)41Ar cross section was measured at average deuteron energies of 3.6 MeV, 5.5 MeV, and 7.0 MeV using an activation method. A 16-MeV deuteron beam produced by Lawrence Berkeley National Laboratory's 88-Inch Cyclotron was degraded to each energy by nickel foils and the front wall of an aluminum gas chamber. The reduced-energy deuterons were used to activate a sample of natAr gas. After each irradiation, the gas chamber's  41Ar activation was measured with a high-purity germanium detector. The cross sections measured were larger than a previous measurement by ∼40%.


Assuntos
Ciclotrons
11.
Nano Lett ; 10(3): 923-30, 2010 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-20121212

RESUMO

We employ sub-picosecond TA spectroscopy on operating P3HT:PCBM devices to probe the effect of annealing on charge transfer dynamics and nanoscale morphology. Our measurement configuration allows us to remove the effect of high excitation densities that would otherwise dominate. Charge transfer in pristine P3HT:PCBM devices proceeds on a sub-picosecond time scale, implying molecular level intermixing and explaining the more localized character of excitons and charges. In annealed devices, annealing results in diffusion-limited charge generation with a half-life time of approximately 3 ps, complete only after 30 ps. This is the result of exclusion of PCBM molecules and ordering of P3HT domains and is correlated with improved photovoltaic efficiency. We are able to use the spectra and dynamics of optical excitations themselves to interpret blend morphologies on the appropriate time- and length scales of photoinduced charge generation.


Assuntos
Fulerenos/química , Nanoestruturas/química , Nanoestruturas/ultraestrutura , Nanotecnologia/métodos , Compostos Organosselênicos/química , Análise Espectral/métodos , Transporte de Elétrons
12.
Appl Radiat Isot ; 170: 109625, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33618214

RESUMO

A discrepancy, well outside reported uncertainties, has been observed between the accepted and measured values of the intensity ratio of the two strongest γ rays following 61Cu ß+ decay. This discrepancy has significant impact since the natNi(d,x)61Cu reaction has historically been one of only a few IAEA recommendations for use as a deuteron flux monitor and a considerable number of published cross sections measured in ratio to that beam monitor cross section may depend on the choice of either the first or second strongest γ ray in those calculations. To determine the magnitude of this error most precisely, over a hundred separate measurements of the 283 keV to 656 keV γ-ray emission ratio were collected from seven experiments and a variety of detectors and detection geometries. A weighted average of all these measurements indicates an error in the value listed in the Nuclear Data Sheets of 11% in either the primary or second-highest intensity γ ray of 61Cu, potentially introducing an 11% error in 61Cu production cross section measurements, cross sections using nickel activation as a deuteron beam current monitor, or in dose rates when 61Cu is used in nuclear medicine. General agreement with the Data Sheets with ten other intensity ratios suggests the most probable error is in the secondary (656 keV) emission, which accordingly should be updated from 10.8% to 9.69%.

13.
J Clin Microbiol ; 48(3): 831-5, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20042626

RESUMO

Nonserotypeable pneumococci (NSP) are commonly carried by Australian Indigenous children in remote communities. The purpose of this study was to characterize carriage isolates of NSP from Indigenous children vaccinated with the seven-valent pneumococcal conjugate vaccine (PCV7) and to use these data to guide decisions on reporting of NSP. A total of 182 NSP were characterized by BOX typing, antibiogram analysis, and multilocus sequence typing (MLST) of common BOX types. NSP positive for the wzg capsule gene were analyzed by a multiplex PCR-based reverse line blot hybridization assay (mPCR/RLB-H) targeting capsule genes to determine the serotype. Among 182 NSP, 49 BOX types were identified. MLST of 10 representative isolates found 7 STs, including ST448 (which accounted for 11% of NSP). Non-penicillin susceptibility was evident in 51% of the isolates. Pneumococcal wzg sequences were detected in only 23 (13%) NSP, including 10 that contained an approximately 1.2-kb insert in the region. mPCR/RLB-H identified serotype 14 wzy sequences in all 10 NSP, and 1 also contained a serotype 3-specific wze sequence. Among the remaining 13 wzg-positive NSP, few belonged to the serotypes represented in PCV7. It appears that most NSP identified in Australian Indigenous children are from a true nonencapsulated lineage. Few NSP represented serotypes in PCV7 that suppress capsular expression. High rates of carriage and penicillin resistance and the occasional presence of capsule genes suggest a role for NSP in the maintenance and survival of capsulated pneumococci. To avoid the inflation of pneumococcal carriage and antibiotic resistance rates, in clinical trials, we recommend separate reporting of rates of capsular strains and NSP and the exclusion of data for NSP from primary analyses.


Assuntos
Cápsulas Bacterianas/genética , Portador Sadio/epidemiologia , Infecções Pneumocócicas/epidemiologia , Vacinas Pneumocócicas/imunologia , Streptococcus pneumoniae/classificação , Streptococcus pneumoniae/isolamento & purificação , Austrália/epidemiologia , Cápsulas Bacterianas/biossíntese , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Proteínas de Transporte/genética , Portador Sadio/microbiologia , Criança , Pré-Escolar , Impressões Digitais de DNA , Genótipo , Vacina Pneumocócica Conjugada Heptavalente , Humanos , Mutação INDEL , Lactente , Recém-Nascido , Epidemiologia Molecular , Resistência às Penicilinas , Infecções Pneumocócicas/microbiologia , Grupos Populacionais , Sorotipagem , Streptococcus pneumoniae/genética
14.
Phys Rev Lett ; 104(17): 177701, 2010 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-20482142

RESUMO

We present direct spectroscopic evidence for substantial subnanosecond charge recombination in polymer-polymer blend photovoltaic devices. Early dynamics are dominated by exciton-charge interactions associated with high initial excitation densities. Independent of density, 30% of charges subsequently recombine geminately within just 2 nanoseconds, in contrast with fullerene blends. The remainder recombines with a half-life of approximately 200 ns. The morphological invariance of subnanosecond recombination suggests that its origin is inherent in the molecular structure at the polymer-polymer interface.

15.
Science ; 172(3986): 945-6, 1971 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-5573565

RESUMO

L-N-Acetylhistidine crystallizes from aqueous solution as the monohydrate. The crystals are triclinic, space group P1, with two formula units per cell. The structural solution was accomplished by direct methods. The two independent molecules have very different conformations, one open and one closed. These two conformations are compared with those found in other histidine structures.


Assuntos
Cristalografia , Histidina , Acetatos
16.
Science ; 187(4177): 656, 1975 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-803711

RESUMO

Corneal epithelium from hamsters dying of transmissible mink encephalopathy contained a virus titer of 10-4.8 times the 50 percent lethal dose (10-4.8 LD50) per 0.05 milliliter when assayed as a cell suspension derived directly from the infected animal. After one passage in tissue culture, an equivalent concentration of cells contained only 10-0.8 LD50 per 0.05 milliliter.. It is concluded that corneal tissues are infectious; the infectivity may be mainly associated with free nerve endings. However, the most important immediate inference is that corneas from human beings affected with Creuzfeldt-Jakob disease are likely to be lethal if transplanted to healthy recipients.


Assuntos
Córnea/microbiologia , Síndrome de Creutzfeldt-Jakob/transmissão , Modelos Animais de Doenças , Vison , Doenças por Vírus Lento/transmissão , Animais , Transplante de Córnea , Cricetinae , Humanos , Transplante Homólogo , Replicação Viral , Vírus não Classificados/crescimento & desenvolvimento
17.
Science ; 192(4237): 390-1, 1976 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-1257776

RESUMO

Airpuff-elicited eyeblink, like many other reflexes, may be inhibited when an auditory stimulus precedes the reflex-eliciting stimulus by approximately 100 milliseconds. This inhibition is greater when the auditory stimulus is delivered to one ear than when it is presented binaurally.


Assuntos
Estimulação Acústica , Pálpebras/fisiologia , Reflexo , Humanos
18.
Science ; 169(3950): 1088-90, 1970 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-4988714

RESUMO

A progressive, fatal spongiform encephalopathy developed in three squirrel monkeys 11 months after inoculation with primate-passaged transmissible mink encephalopathy agent. The clinical symptoms and histopathologic and electron microscopic findings suggest that this naturally occurring disease of mink has been transmitted experimentally to squirrel monkeys.


Assuntos
Transtornos das Proteínas Sanguíneas/veterinária , Encefalopatias/veterinária , Vison , Doenças dos Macacos/patologia , Viroses/veterinária , Animais , Apraxias , Ataxia , Encefalopatias/etiologia , Encefalopatias/patologia , Córtex Cerebral/patologia , Feminino , Haplorrinos , Humanos , Microscopia Eletrônica , Doenças dos Macacos/etiologia , Medula Espinal/patologia , Tremor , Viroses/patologia
19.
Science ; 275(5303): 1113-5, 1997 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-9027309

RESUMO

During running, muscles and tendons must absorb and release mechanical work to maintain the cyclic movements of the body and limbs, while also providing enough force to support the weight of the body. Direct measurements of force and fiber length in the lateral gastrocnemius muscle of running turkeys revealed that the stretch and recoil of tendon and muscle springs supply mechanical work while active muscle fibers produce high forces. During level running, the active muscle shortens little and performs little work but provides the force necessary to support body weight economically. Running economy is improved by muscles that act as active struts rather than working machines.


Assuntos
Locomoção/fisiologia , Contração Muscular , Músculo Esquelético/fisiologia , Tendões/fisiologia , Perus/fisiologia , Animais , Fenômenos Biomecânicos , Eletromiografia , Membro Posterior , Contração Isométrica , Corrida , Estresse Mecânico , Transdutores
20.
Science ; 172(3985): 859-61, 1971 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-4102123

RESUMO

A progressive, fatal spongiform polioencephalopathy was induced in mink intracerebrally inoculated with a suspension of brain from a Suffolk sheep with naturally acquired scrapie. The clinical signs and pathological lesions of the experimental disease were indistinguishable from transmissible mink encephalopathy, a disease of undetermined origin that occurs in mink.


Assuntos
Vison , Scrapie/patologia , Animais , Córtex Cerebral/patologia , Microscopia Eletrônica , Ovinos , Coloração e Rotulagem
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