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1.
Mil Psychol ; : 1-13, 2023 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-37699140

RESUMO

Sensemaking and decision-making are fundamental components of applied Intelligence, Surveillance, and Reconnaissance (ISR). Analysts acquire information from multiple sources over a period of hours, days, or even over the scale of months or years, that must be interpreted and integrated to predict future adversarial events. Sensemaking is essential for developing an appropriate mental model that will lead to accurate predictions sooner. Decision Support Systems (DSS) are one proposed solution to improve analyst decision-making outcomes by leveraging computers to conduct calculations that may be difficult for human operators and provide recommendations. In this study, we tested two simulated DSS that were informed by a Bayesian Network Model as a potential prediction-assistive tool. Participants completed a simulated multi-day, multi-source intelligence task and were asked to make predictions regarding five potential outcomes on each day. Participants in both DSS conditions were able to converge on the correct solution significantly faster than the control group, and between 36-44% more of the sample was able to reach the correct conclusion. Furthermore, we found that a DSS representing projected outcome probabilities as numerical, rather than using verbal ordinal labels, were better able to differentiate which outcomes were extremely unlikely than the control group or verbal-probability DSS.

3.
Crit Care Med ; 44(9): 1663-74, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-27071068

RESUMO

OBJECTIVES: Cardiac arrest is associated with morbidity and mortality because of cerebral ischemia. Therefore, we tested the hypothesis that higher regional cerebral oxygenation during resuscitation is associated with improved return of spontaneous circulation, survival, and neurologic outcomes at hospital discharge. We further examined the validity of regional cerebral oxygenation as a test to predict these outcomes. DESIGN: Multicenter prospective study of in-hospital cardiac arrest. SETTING: Five medical centers in the United States and the United Kingdom. PATIENTS: Inclusion criteria are as follows: in-hospital cardiac arrest, age 18 years old or older, and prolonged cardiopulmonary resuscitation greater than or equal to 5 minutes. Patients were recruited consecutively during working hours between August 2011 and September 2014. Survival with a favorable neurologic outcome was defined as a cerebral performance category 1-2. INTERVENTIONS: Cerebral oximetry monitoring. MEASUREMENTS AND MAIN RESULTS: Among 504 in-hospital cardiac arrest events, 183 (36%) met inclusion criteria. Overall, 62 of 183 (33.9%) achieved return of spontaneous circulation, whereas 13 of 183 (7.1%) achieved cerebral performance category 1-2 at discharge. Higher mean ± SD regional cerebral oxygenation was associated with return of spontaneous circulation versus no return of spontaneous circulation (51.8% ± 11.2% vs 40.9% ± 12.3%) and cerebral performance category 1-2 versus cerebral performance category 3-5 (56.1% ± 10.0% vs 43.8% ± 12.8%) (both p < 0.001). Mean regional cerebral oxygenation during the last 5 minutes of cardiopulmonary resuscitation best predicted the return of spontaneous circulation (area under the curve, 0.76; 95% CI, 0.69-0.83); regional cerebral oxygenation greater than or equal to 25% provided 100% sensitivity (95% CI, 94-100) and 100% negative predictive value (95% CI, 79-100); regional cerebral oxygenation greater than or equal to 65% provided 99% specificity (95% CI, 95-100) and 93% positive predictive value (95% CI, 66-100) for return of spontaneous circulation. Time with regional cerebral oxygenation greater than 50% during cardiopulmonary resuscitation best predicted cerebral performance category 1-2 (area under the curve, 0.79; 95% CI, 0.70-0.88). Specifically, greater than or equal to 60% cardiopulmonary resuscitation time with regional cerebral oxygenation greater than 50% provided 77% sensitivity (95% CI,:46-95), 72% specificity (95% CI, 65-79), and 98% negative predictive value (95% CI, 93-100) for cerebral performance category 1-2. CONCLUSIONS: Cerebral oximetry allows real-time, noninvasive cerebral oxygenation monitoring during cardiopulmonary resuscitation. Higher cerebral oxygenation during cardiopulmonary resuscitation is associated with return of spontaneous circulation and neurologically favorable survival to hospital discharge. Achieving higher regional cerebral oxygenation during resuscitation may optimize the chances of cardiac arrest favorable outcomes.


Assuntos
Isquemia Encefálica/diagnóstico , Circulação Cerebrovascular/fisiologia , Parada Cardíaca/fisiopatologia , Parada Cardíaca/terapia , Idoso , Isquemia Encefálica/etiologia , Isquemia Encefálica/mortalidade , Reanimação Cardiopulmonar , Feminino , Parada Cardíaca/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Oximetria , Alta do Paciente , Valor Preditivo dos Testes , Estudos Prospectivos , Taxa de Sobrevida , Resultado do Tratamento , Reino Unido , Estados Unidos
5.
Hosp Pediatr ; 4(3): 135-40, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24785555

RESUMO

BACKGROUND: The Pediatric Early Warning System (PEWS) was created to identify unstable patients before their deterioration. Rapid response teams (RRTs) were developed to assist with management of such patients. In 2009, our institution mandated the activation of RRTs if a PEWS score was elevated (ie, ≥5). OBJECTIVES: The goal of this study was to examine changes in characteristics of RRT calls before and after the implementation of a mandatory hospital policy requiring RRT activation due to an elevated PEWS score. METHODS: This study was a retrospective database review, with RRT data from June 2007 to December 2010 examined. A total of 44 RRTs were recorded before mandatory triggering and 69 RRTs afterward in the study period (P = .32). RESULTS: Compared with the premandatory group, the mandatory triggering group found that tachycardia was a more frequent trigger for RRTs, with an increase of 26.1% (P = .004). RRTs triggered by a change in mental status/agitation decreased by 22.9% (P = .009). An increase of 15.1% of RRTs required no interventions with mandatory triggering. Nighttime RRTs increased by17.5% (P = .07). There was a trend toward decreased PICU transfers in the mandatory triggering group, with no significant change in code blue calls. CONCLUSIONS: A hospital policy of mandating RRT activation based on PEWS scores increased nighttime calls and altered the primary reasons for RRT activation in our center, with no evidence of improvements in patient care. These findings should be interpreted with caution given the relatively rare outcomes the policy is intended to prevent; however, our findings highlight the difficulties inherent in evaluating methods to improve pediatric patient safety.


Assuntos
Equipe de Respostas Rápidas de Hospitais/organização & administração , Índice de Gravidade de Doença , Criança , Indicadores Básicos de Saúde , Equipe de Respostas Rápidas de Hospitais/estatística & dados numéricos , Humanos , Programas Obrigatórios , Modelos Organizacionais , Política Organizacional , Pediatria/organização & administração , Pediatria/normas , Estudos Retrospectivos , Taquicardia
6.
Brain Imaging Behav ; 7(4): 543-53, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23955490

RESUMO

To assess the feasibility of a cognitive rehabilitation program in breast cancer survivors (BCS) with persistent post-treatment cognitive complaints. BCS with cognitive complaints, 18-months to 5-years post-treatment, were recruited for a once-weekly, five-week, group cognitive training intervention. Outcome measures included self-reported mood and cognitive function, and neurocognitive tests administered at pre-intervention, immediate-, two-month and four-month post-intervention. A sub-study in eight participants evaluated resting state quantitative electroencephalography (qEEG) changes from pre- to immediate post-intervention in relationship to post-intervention changes in cognitive complaints. Twenty-seven BCS completed the protocol and tolerated the intervention well. We observed significant reductions in total and memory-specific cognitive complaints from pre-intervention to immediate post-intervention (p = 0.031 and p = 0.009, respectively) and at four-months post-intervention (p < 0.0001 and p < 0.001, respectively). Significant improvement in neurocognitive tests were found for Symbol Digit, Stroop, and Trails A tests (df = 26, all p's <0.05). Effect sizes for changes from pre-intervention to immediate and to four-month post intervention ranged from 0.429 to 0.607, and from 0.439 to 0.741, respectively. Increase in qEEG absolute alpha power over the course of the intervention was associated with reduced complaints at immediate post-intervention (r = -0.78, p = 0.021), two-months (r range = -0.76 to -0.82, p-value range 0.004 to 0.03), and four-months (r = -0.71, p = 0.048). A five-week group cognitive training intervention is feasible and well tolerated. Cognitive complaints and neurocognitive test performances showed positive changes. qEEG may serve as a potential biomarker for improvement in self-reported complaints. A randomized clinical trial is underway to test the efficacy of the intervention.


Assuntos
Atividades Cotidianas , Neoplasias da Mama/complicações , Transtornos Cognitivos/etiologia , Transtornos Cognitivos/reabilitação , Adulto , Idoso , Neoplasias da Mama/reabilitação , Transtornos Cognitivos/psicologia , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Qualidade de Vida , Sobreviventes , Resultado do Tratamento
7.
Proc Natl Acad Sci U S A ; 110(15): 5785-90, 2013 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-23530201

RESUMO

The late pre-Hispanic period in the US Southwest (A.D. 1200-1450) was characterized by large-scale demographic changes, including long-distance migration and population aggregation. To reconstruct how these processes reshaped social networks, we compiled a comprehensive artifact database from major sites dating to this interval in the western Southwest. We combine social network analysis with geographic information systems approaches to reconstruct network dynamics over 250 y. We show how social networks were transformed across the region at previously undocumented spatial, temporal, and social scales. Using well-dated decorated ceramics, we track changes in network topology at 50-y intervals to show a dramatic shift in network density and settlement centrality from the northern to the southern Southwest after A.D. 1300. Both obsidian sourcing and ceramic data demonstrate that long-distance network relationships also shifted from north to south after migration. Surprisingly, social distance does not always correlate with spatial distance because of the presence of network relationships spanning long geographic distances. Our research shows how a large network in the southern Southwest grew and then collapsed, whereas networks became more fragmented in the northern Southwest but persisted. The study also illustrates how formal social network analysis may be applied to large-scale databases of material culture to illustrate multigenerational changes in network structure.


Assuntos
Apoio Social , Arqueologia/métodos , Cerâmica , Bases de Dados Factuais , Sistemas de Informação Geográfica , Geografia , História Medieval , Migração Humana , Humanos , Sudoeste dos Estados Unidos , Fatores de Tempo , Estados Unidos
8.
Breast Cancer Res Treat ; 134(2): 759-67, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22706631

RESUMO

Low serum vitamin D levels have been associated with poor outcomes in women diagnosed with early breast cancer. However, no randomized controlled trials (RCTs) have been performed to determine whether vitamin D supplementation might be an effective intervention in this population. We prospectively evaluated vitamin D adequacy and supplementation rates in a contemporary cross-sectional sample of breast cancer patients from 2 large urban centers and examined the feasibility of an RCT of vitamin D supplementation. Women with recently diagnosed early breast cancer were prospectively identified and recruited in Toronto and Los Angeles between March 2009 and January 2010. Anthropometric measurements, dietary, lifestyle, and medication histories were obtained by means of structured questionnaires and interviews. Tumor and treatment characteristics were abstracted from clinical records and blood samples were collected for analysis of 25-OH vitamin D. 173 eligible patients (median age 57) were enrolled. Clinical and treatment characteristics were similar between centres. 84.4 % of women reported use of vitamin D-containing supplements with median daily doses of 1,400 IU. Median 25-OH vitamin D levels were 85.5 and 98.5 nmol/L (P = 0.1), and levels of deficiency (<50 nmol/L), insufficiency (50-72 nmol/L), and adequacy (>72 nmol/L) were 3.8, 23.8, 72.5 % (Toronto) and 4.3, 20.7, 75 % (Los Angeles). 25-OH vitamin D levels were strongly correlated with vitamin D supplement use (r = 0.41, P < 0.0001). 68 % of women expressed willingness to participate in a vitamin D supplementation RCT; however, only 12.7 % of the study population met the pre-specified feasibility criteria (25-OH vitamin D <72 nmol/L, willing to participate, and taking ≤1,000 IU vitamin D supplement/day). Both vitamin D levels and supplementation rates are higher than in previous reports. While the majority of women would be willing to participate in an RCT of vitamin D supplementation, low levels of deficiency/insufficiency and high rates of supplement use would limit the feasibility of such a study.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto , Vitamina D/uso terapêutico , Vitaminas/uso terapêutico , Neoplasias da Mama/sangue , Quimioterapia Adjuvante , Suplementos Nutricionais , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Aceitação pelo Paciente de Cuidados de Saúde , Seleção de Pacientes , Placebos , Estatísticas não Paramétricas , Vitamina D/sangue , Vitaminas/sangue
10.
Aviat Space Environ Med ; 77(1): 26-31, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16422450

RESUMO

INTRODUCTION: Helicopter cockpits are very noisy and this noise must be reduced for effective communication. The standard U.S. Army aviation helmet is equipped with a noise-canceling acoustic microphone, but some ambient noise still is transmitted. Throat microphones are not sensitive to air molecule vibrations and thus, transmittal of ambient noise is reduced. It is possible that throat microphones could enhance speech communication in helicopters, but speech intelligibility with the devices must first be assessed. In the current study, speech intelligibility of signals generated by an acoustic microphone, a throat microphone, and by the combined output of the two microphones was assessed using the Modified Rhyme Test (MRT). METHODS: Stimulus words were recorded in a reverberant chamber with ambient broadband noise intensity at 90 and 106 dBA. Listeners completed the MRT task in the same settings, thus simulating the typical environment of a rotary-wing aircraft. RESULTS: Results show that speech intelligibility is significantly worse for the throat microphone (average percent correct = 55.97) than for the acoustic microphone (average percent correct = 69.70), particularly for the higher noise level. In addition, no benefit is gained by simultaneously using both microphones. A follow-up experiment evaluated different consonants using the Diagnostic Rhyme Test and replicated the MRT results. DISCUSSION: The current results show that intelligibility using throat microphones is poorer than with the use of boom microphones in noisy and in quiet environments. Therefore, throat microphones are not recommended for use in any situation where fast and accurate speech intelligibility is essential.


Assuntos
Acústica , Amplificadores Eletrônicos , Ruído Ocupacional , Inteligibilidade da Fala , Adulto , Medicina Aeroespacial , Feminino , Humanos , Masculino , Faringe
12.
J Nutr ; 134(1): 79-85, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14704297

RESUMO

Dietary Mg intake has been linked to osteoporosis. Previous studies have demonstrated that severe Mg deficiency [0.04% of nutrient requirement (NR)] results in osteoporosis in rodent models. We assessed the effects of more moderate dietary Mg restriction (10% of NR) on bone and mineral metabolism over a 6-mo experimental period in rats. At 2, 4 and 6 mo, serum Mg, Ca, parathyroid hormone (PTH), 1,25-dihydroxy-vitamin D, alkaline phosphatase, osteocalcin and urine pyridinoline were measured. Femurs and tibiae were collected for measurement of mineral content, microcomputerized tomography, histomorphometry, and immunocytochemical localization. By 2 mo, profound Mg deficiency had developed as assessed by marked hypomagnesemia and up to a 51% reduction in bone Mg content. These features continued through 6 mo of study. Serum Ca was slightly but significantly higher in Mg-deficient rats than in controls at all time points. At 2 mo, serum PTH was elevated in Mg-deficient rats but was significantly decreased at 6 mo in contrast to control rats in which PTH rose. Serum 1,25-dihydroxy-vitamin D was significantly lower than in controls at 4 and 6 mo. A significant fall in both serum alkaline phosphatase and osteocalcin suggested decreased osteoblast activity. Histomorphometry demonstrated decreased bone volume and trabecular thickness. This was confirmed by microcomputerized tomography analysis, which also showed that trabecular volume, thickness and number were significantly lower in Mg-deficient rats. Increased bone resorption was suggested by an increase in osteoclast number over time compared with controls as well as surface of bone covered by osteoclasts and eroded surface, but there was no difference in osteoblast numbers. The increased bone resorption may be due to an increase in TNF-alpha because immunocytochemical localization of TNF-alpha in osteoclasts was 199% greater than in controls at 2 mo, 75% at 4 mo and 194% at 6 mo. The difference in TNF-alpha may be due to substance P, which was 250% greater than in controls in mononuclear cells at 2 mo and 266% at 4 mo. These data demonstrated that a Mg intake of 10% of NR in rats causes bone loss that may be secondary to the increased release of substance P and TNF-alpha.


Assuntos
Doenças Ósseas/etiologia , Dieta , Deficiência de Magnésio/complicações , Magnésio/administração & dosagem , Substância P/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Envelhecimento , Fosfatase Alcalina/sangue , Aminoácidos/sangue , Animais , Peso Corporal , Densidade Óssea , Remodelação Óssea , Osso e Ossos/química , Calcitriol/sangue , Cálcio/sangue , Imuno-Histoquímica , Macrófagos/química , Magnésio/sangue , Megacariócitos/química , Necessidades Nutricionais , Osteocalcina/sangue , Osteoclastos/química , Hormônio Paratireóideo/sangue , Ratos , Ratos Sprague-Dawley , Fator de Necrose Tumoral alfa/análise
13.
Biomaterials ; 24(26): 4785-97, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14530076

RESUMO

Cytokines associated with osteolysis have been demonstrated in tissues surrounding failed metal-metal (MM) total hip replacements (THRs). The objective of the present study was to semi-quantify the amounts of inflammatory cytokines in tissues from 28 failed MM THRs, and determine their relationship with the quantity of metal particles. Paraffin sections were immunohistochemically stained with monoclonal antibodies: anti-IL-1-beta, anti-IL-6 and anti-TNF-alpha. Cytokines and metal particles were rated in 10 fields per tissue using standard light microscopy. Because of the use of light microscopy, only relatively large particles or agglomerations of particles were visible. Therefore, a polarized light and a semi-quantitative scheme based on the discoloration of cell cytoplasms induced by the presence of particles were used to evaluate the quantity of metal particles. Results showed an overall higher amount of IL-6 than IL-1beta while TNF-alpha remained at very low levels. For each patient, the average IL-1beta and IL-6 ratings decreased when the average particle rating increased, following a linear regression, with relatively high correlation factors (r=-0.69 for IL-1beta and r=-0.57 for IL-6). IL-1beta decreased about twice as fast as IL-6. TNF-alpha, remaining at very low levels, did not demonstrate any correlation with particle rating. When multiple tissues were available for the same patient, the correlation factors between the average cytokine and particle ratings were highly variable between samples, demonstrating the heterogeneity between the tissues from the same patient. At the cellular level, there was an even higher correlation between the quantity of metal particles and the production of IL-1beta and IL-6 (r=-0.99), while TNF-alpha did not demonstrate any correlation, remaining at very low levels. In conclusion, this study showed that tissues surrounding failed MM THRs with low to moderate quantities of metal particles can induce the production of potentially osteolytic cytokines. However, the overall number of cells producing these cytokines tended to be lower than that typically seen in tissues surrounding metal-polyethylene THRs.


Assuntos
Citocinas/metabolismo , Corpos Estranhos/metabolismo , Corpos Estranhos/patologia , Articulação do Quadril/metabolismo , Articulação do Quadril/patologia , Prótese de Quadril/efeitos adversos , Metais/análise , Medição de Risco/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Análise de Falha de Equipamento/métodos , Feminino , Corpos Estranhos/etiologia , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Falha de Prótese , Infecções Relacionadas à Prótese/etiologia , Infecções Relacionadas à Prótese/metabolismo , Infecções Relacionadas à Prótese/patologia , Estatística como Assunto , Distribuição Tecidual
14.
BMC Musculoskelet Disord ; 4: 7, 2003 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-12702215

RESUMO

BACKGROUND: Dietary magnesium (Mg) deficiency in the mouse perturbs bone and mineral homeostasis. The objective of the present study was to evaluate bone mineral density of the femur in control and Mg-deficient mice. METHODS: BALB/c mice aged 28 days at study initiation were maintained on a normal or Mg deficient (0.0002% Mg) diet, and at time points 0, 2, 4 or 6 weeks bones were harvested for bone mineral density analysis. Peripheral quantitative computed tomography (pQCT) was used to assess the trabecular metaphyseal compartment and the cortical midshaft. RESULTS: Although mean total bone density of the femoral midshaft in Mg deficient mice did not differ significantly from controls throughout the study, the trabecular bone compartment showed significantly decreased mineral content after 4 (p < 0.001) and 6 weeks (p < 0.001) of Mg depletion. CONCLUSIONS: This study demonstrates the profound effect of Mg depletion on the trabecular compartment of bone, which, with its greater surface area and turnover, was more responsive to Mg depletion than cortical bone in the appendicular skeleton of the mouse.


Assuntos
Densidade Óssea , Fêmur/metabolismo , Deficiência de Magnésio/metabolismo , Animais , Peso Corporal , Dieta , Feminino , Fêmur/patologia , Magnésio/metabolismo , Deficiência de Magnésio/patologia , Deficiência de Magnésio/fisiopatologia , Camundongos , Camundongos Endogâmicos BALB C
15.
J Exp Psychol Hum Percept Perform ; 28(2): 367-78, 2002 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11999860

RESUMO

This study evaluated the relationship between primitive and scheme-driven grouping (A. S. Bregman, 1990) by comparing the ability of different listeners to detect single note changes in 3-voice musical compositions. Primitive grouping was manipulated by the use of 2 distinctly different compositional styles (homophony and polyphony). The effects of scheme-driven processes were tested by comparing performance of 2 groups of listeners (musicians and nonmusicians) and by varying task demands (integrative and selective listening). Following previous studies, which had tested only musically trained participants, several variables were manipulated within each compositional style. The results indicated that, although musicians demonstrated a higher sensitivity to changes than did nonmusicians, the 2 groups exhibited similar patterns of sensitivity under a variety of conditions.


Assuntos
Percepção Auditiva , Música/psicologia , Voz , Logro , Estimulação Acústica , Análise de Variância , Atenção , Humanos , Fonética , Discriminação da Altura Tonal , Psicoacústica , Desempenho Psicomotor
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