Predicting knee cartilage loss using adaptive partitioning of cartilage thickness maps

This study investigates whether measures of knee cartilage thickness can predict future loss of knee cartilage. A slow and a rapid progressor group was determined using longitudinal data, and anatomically aligned cartilage thickness maps were extracted from MRI at baseline. A novel machine learning framework was then trained using these maps. Compared to measures of mean cartilage plate thickness, group separation was increased by focusing on local cartilage differences. This result is central for clinical trials where inclusion of rapid progressors may help reduce the period needed to study effects of new disease-modifying drugs for osteoarthritis.     

Neural coding of nociceptive stimuli—from rat spinal neurones to human perception

Translational studies are key to furthering our understanding of nociceptive signalling and bridging the gaps between molecules and pathways to the patients. This requires use of appropriate preclinical models that accurately depict outcome measures used in humans. Whereas behavioural animal studies classically involve reports related to nociceptive thresholds of, for example, withdrawal, electrophysiological recordings of spinal neurones that receive convergent input from primary afferents permits investigation of suprathreshold events and exploration of the full-range coding of different stimuli. We explored the central processing of nociceptive inputs in a novel parallel investigation between rats and humans. Using radiant laser pulses, we first compared the electrophysiological responses of deep wide dynamic range and superficial nociceptive-specific neurones in the rat dorsal horn with human psychophysics and cortical responses. Secondly, we explored the effects of spatial summation using laser pulses of identical energy and different size. We observed 3 main findings. Firstly, both rodent and human data confirmed that neodymium–yttrium aluminium perovskite laser stimulation is a nociceptive-selective stimulus that never activates Aβ afferents. Secondly, graded laser stimulation elicited similarly graded electrophysiological and behavioural responses in both species. Thirdly, there was a significant degree of spatial summation of laser nociceptive input. The remarkable similarity in rodent and human coding indicates that responses of rat dorsal horn neurones can translate to human nociceptive processing. These findings suggest that recordings of spinal neuronal activity elicited by laser stimuli could be a valuable predictive measure of human pain perception.     

我国疾病预防控制中心人员编制配置水平的空间分析

目的:本文分析了2004—2019年省级疾病预防控制中心(以下简称疾控中心)编制人员空间分布及变化特征,提出人员优化配置建议。方法:通过GeoDa分析编制人员全局和局域空间差异。结果:我国疾控中心编制人员配置总体上由西向东递减;2019年,23个省疾控中心人员数量不符合编制标准,14个省专业技术人员占比、3个省卫生技术人员占比低于标准;人力资源全局空间聚集水平不断下降,西部高—高聚集、东部低—低聚集,差异有统计学意义;不同时间段人力资源空间格局及其演变趋势受重大事件或政策影响。结论:疾控中心人力资源总体空间分布差距不断缩小,但省级水平分布不均,内部结构有待改善;应兼顾提升编制人员整体数量、改善不同类别编制人员占比,针对性弥补疾控中心的人员缺口。     

Local Ecological Factors,Ultrafine Particulate Concentrations,and Asthma Prevalence Rates in Buffalo,New York,Neighborhoods

Previous to this study various healthcare utilization studies and house-to-house surveys had shown that Buffalo's west side had a high utilization rate for asthma and high asthma prevalence in comparison with neighboring communities. The relative contributions of traffic-related pollution and personal and local ecological factors to the high asthma rates were still unknown. To investigate the potential roles of personal home environmental factors and local ecological factors in variations of asthma prevalence in Buffalo neighborhoods, we conducted a cross-sectional survey of a systematic random sample of 2000 households in the city of Buffalo, New York, with a response rate of 80.4%. We found that the odds of having at least one person with asthma per household on Buffalo's west side was 2.57 times [95% confidence interval (CI) = 1.85–3.57] that of Buffalo's east side. There were no statistically significant differences in the odds of finding at least one person with asthma in households of other Buffalo neighborhoods. We further found no difference in the odds of having asthma on Buffalo's west side even after correcting for race/ethnicity, household triggers of asthma, and socioeconomic factors. Monitoring ultrafine particulates showed increased levels in communities downwind of the Peace Bridge Complex and major roadways supplying it. A multiple-regression model showed that asthma prevalence may be influenced by humidity and ultrafine particulate concentrations. These results suggest that increased asthma risk may be influenced by chronic exposure to personal and local ecological factors.     

The impact of environmental and climatic variation on the spatiotemporal trends of hospitalized pediatric diarrhea in Ho Chi Minh City,Vietnam

It is predicted that the integration of climate-based early warning systems into existing action plans will facilitate the timely provision of interventions to diarrheal disease epidemics in resource-poor settings. Diarrhea remains a considerable public health problem in Ho Chi Minh City (HCMC), Vietnam and we aimed to quantify variation in the impact of environmental conditions on diarrheal disease risk across the city. Using all inpatient diarrheal admissions data from three large hospitals within HCMC, we developed a mixed effects regression model to differentiate district-level variation in risk due to environmental conditions from the overarching seasonality of diarrheal disease hospitalization in HCMC. We identified considerable spatial heterogeneity in the risk of all-cause diarrhea across districts of HCMC with low elevation and differential responses to flooding, air temperature, and humidity driving further spatial heterogeneity in diarrheal disease risk. The incorporation of these results into predictive forecasting algorithms will provide a powerful resource to aid diarrheal disease prevention and control practices in HCMC and other similar settings.     

Spatial learning in a virtual reality-based task is altered in very preterm children

Very preterm births prevent a complete development of the nervous system. The hippocampus is especially vulnerable in this population since the perinatal period is critical for its growth and development. Learning and memory abilities, like spatial memory, depend on the hippocampal integrity. In this study we applied virtual-reality-based tasks to assess spatial memory in a sample of 20 very preterm children of 7 and 8 years of age. Two different conditions of difficulty were used. Very preterm children performed poorly in the task in comparison with the control group. They committed more errors than controls searching for the rewarded positions. However, no significant differences were observed in the mean speed, an index of the motor abilities and joystick handling. These results suggest that the hippocampal function is affected in this sample. Nevertheless, other variables to consider are discussed.     

A flow-based statistical model integrating spatial and nonspatial dimensions to measure healthcare access

Assessing access to healthcare for an entire healthcare system involves accounting for demand, supply, and geographic variation. In order to capture the interaction between healthcare services and populations, various measures of healthcare access have been utilized, including the popular two-step floating catchment area (2SFCA) method. However, despite the many advantages of 2SFCA, the problems, such as inappropriate assumption of healthcare demand and failure to capture cascading effects across the system have not been satisfactorily addressed. In this paper, a statistical model for evaluating flows of individuals was added to the 2SFCA method (hereafter we refer to it as F2SFCA) in order to overcome limitations associated with its current restriction. The proposed F2SFCA model can incorporate both spatial and nonspatial dimensions and thus synthesizes them into one framework. Moreover, the proposed F2SFCA model can be easily adapted to measure access for different types of individuals, over different service provider types, or with capacity constraints in a healthcare system. We implemented the proposed model in a case study assessing access to healthcare for the elderly in Taipei City, Taiwan, and compared the weaknesses and strengths to the 2SFCA method and its variations.     

Small area estimation of obesity prevalence and dietary patterns: A model applied to Rio de Janeiro city,Brazil

We propose the use of previously developed small area estimation techniques to monitor obesity and dietary habits in developing countries and apply the model to Rio de Janeiro city. We estimate obesity prevalence rates at the Census Tract through a combinatorial optimization spatial microsimulation model that matches body mass index and socio-demographic data in Brazil's 2008–9 family expenditure survey with Census 2010 socio-demographic data. Obesity ranges from 8% to 25% in most areas and affects the poor almost as much as the rich. Male and female obesity rates are uncorrelated at the small area level. The model is an effective tool to understand the complexity of the problem and to aid in policy design.     

Spatial hearing processing: electrophysiological documentation at subcortical and cortical levels

Abstract

Objective: Recognition of target signal improves when the target and distracted sources are spatially separated, an effect defined as ‘spatial release from masking’ (SRM). The neural mechanisms underpinning SRM are complicated and still need to be identified. The aim of this study was to identify whether objective correlates of SRM can be recorded in either the brainstem or cortex (or both).

Materials and methods: In response to 200 target stimulus blocks, auditory brainstem responses (ABRs), frequency-following responses (FFRs) and cortical auditory evoked potentials (CAEPs) were recorded concurrently from 13 normally hearing adults utilizing two stimulus patterns, flat and staircase, in the presence of randomized distractors at ?5, 0, 5, 10 and 15?dB SNR, and in co-located and separated spatial locations.

Results: FFR F0 amplitude increased for the flat stimuli at ?5?dB SNR, ABR wave V latency decreased for both flat and staircase stimuli in all SNRs and for P1 and N1 latencies due to the noisy CAEPs, drawing any significant conclusion could be subject to further investigation.

Conclusion: These findings suggest that SRM can be objectively recorded concurrently in both the brainstem and auditory cortex. It is speculated that the central auditory system can suppress background noise based on spatial information commencing from the brainstem and that this capability is remarkable in more difficulty listing situations. This study may pave the way to evaluate spatial processing electrophysiologically utilizing FFR amplitude, ABR and CAEPs latencies condition to confirmation of the results of this study, at least at the level of the cortex in future investigation.