The Effect of Healthcare Transition Services on State Level Recidivism

Every state currently offers some amount of healthcare transition services to individuals leaving prison, but there is little research on whether, and how, these services are effective at reducing recidivism. This paper focuses on the extent to which healthcare transition services are effective, and identifies which services are effective, controlling for state spending. Using data provided by the Pew Charitable Trusts, I examine how the number of services offered, as well as the amount spent on prison healthcare within a state affects the recidivism rate at the state level. The primary model is a multivariate ordinary least squares model with state-level recidivism as the dependent variable. Then, I use a separate multivariate model to examine ten transition services that are in less than 80% of states. Next, I estimate the effect of each individual service in a third model. Finally, I use a fixed-effects model to estimate how changes in both total and per-inmate healthcare spending affect recidivism. The results of these models suggest that providing more services lowers recidivism. However, not all transition services are equally effective. Community supervision and transition services that provide for people suffering from substance abuse, namely referrals or appointments, were shown to be among the most effective services. On the other end, mental health appointments were the least effective. Increased access to community supervision is the recommended policy, with individuals getting at least one meeting prior to or just following release. Further research is needed to determine why appointments for individuals suffering from mental illness are so ineffective as well as study how the selection bias of policing may be affecting the results.Bachelor of Art

Matrix Factorization at Scale: a Comparison of Scientific Data Analytics in Spark and C+MPI Using Three Case Studies

We explore the trade-offs of performing linear algebra using Apache Spark, compared to traditional C and MPI implementations on HPC platforms. Spark is designed for data analytics on cluster computing platforms with access to local disks and is optimized for data-parallel tasks. We examine three widely-used and important matrix factorizations: NMF (for physical plausability), PCA (for its ubiquity) and CX (for data interpretability). We apply these methods to TB-sized problems in particle physics, climate modeling and bioimaging. The data matrices are tall-and-skinny which enable the algorithms to map conveniently into Spark's data-parallel model. We perform scaling experiments on up to 1600 Cray XC40 nodes, describe the sources of slowdowns, and provide tuning guidance to obtain high performance

Characterization of twenty-five ovarian tumour cell lines that phenocopy primary tumours

Currently available human tumour cell line panels consist of a small number of lines in each lineage that generally fail to retain the phenotype of the original patient tumour. Here we develop a cell culture medium that enables us to routinely establish cell lines from diverse subtypes of human ovarian cancers with >95% efficiency. Importantly, the 25 new ovarian tumour cell lines described here retain the genomic landscape, histopathology and molecular features of the original tumours. Furthermore, the molecular profile and drug response of these cell lines correlate with distinct groups of primary tumours with different outcomes. Thus, tumour cell lines derived using this methodology represent a significantly improved platform to study human tumour pathophysiology and response to therapy

Identification of the transneuronal homeostatic machinery at a central synapse

Two different kinds of stabilising homeostatic behaviour have been observed in neurons. The first type involves the cell-autonomous maintenance of a cell-identity-based level of electrical activity. Neurons continually monitor their own electrical activity and can adjust many intracellular parameters, such as membrane ion channel densities, to keep this activity within a tight physiological range. The second type of homeostatic behaviour shares the same goal, to maintain a fixed level of electrical activity, but instead of adjusting intracellular parameters, the neuron recruits its synaptic partners to assist in maintaining a genetically prescribed activity level. This behaviour is most easily observed when a neuron is either electrically silenced by expressing an inwardly-rectifying potassium channel or rendered less sensitive to neurotransmitter through mutation of its postsynaptic receptors. Both of these perturbations result in increased synaptic drive from the presynaptic cells, either through increasing the number of neurotransmitter release sites or increasing the probability of release from single release sites. Many genes that are instrumental in the second type of homeostatic behaviour have been identified, mainly at the neuromuscular junction in the peripheral nervous system. However, studies on transsynaptic homeostatic compensation in an intact central nervous system have been few and far between. Also, which, if any, of the homeostatic genes are transcriptionally regulated in the nucleus after the onset of transsynaptic homeostatic adjustment, has not been adequately addressed. This thesis has developed a system to measure transcriptome-wide gene expression levels in presynaptic circuit elements after altering the firing properties of the downstream circuit in the CNS. Many transcriptionally regulated genes have been identified and are now being tested for their potential use as reporters for transsynaptic transcriptional regulation. It might be possible to capitalise on endogenous homeostatic signalling pathways to gain genetic access to synaptically connected neurons.</p

Fast cortical dynamics encode tactile grating orientation during active touch

Touch-based object recognition relies on perception of compositional tactile features like roughness, shape, and surface orientation. However, besides roughness, it remains unclear how these different tactile features are encoded by neural activity that is linked with perception. Here, we establish a cortex-dependent perceptual task in which mice discriminate tactile gratings based on orientation using only their whiskers. Multi-electrode recordings in barrel cortex reveal weak orientation tuning in average firing rates during grating exploration despite high levels of cortical activity. Just before decision, orientation information extracted from fast cortical dynamics more closely resembles concurrent psychophysical measurements than single neuron orientation tuning curves. This temporal code conveys both stimulus and choice/action-related information, suggesting that fast cortical dynamics during exploration of a tactile object both reflect the physical stimulus and impact the decision.The submission contains txt files with descriptions of the python dictionaries that contain all the relevant data.Go-NoGo behavior, high speed videos of whisker interactions with gratings, and multi-electrode extracellular electrophysiolog

Fast cortical dynamics encode tactile grating orientation during active touch

International audienceTouch-based object recognition relies on perception of compositional tactile features like roughness, shape, and surface orientation. However, besides roughness, it remains unclear how these different tactile features are encoded by neural activity that is linked with perception. Here, we establish a cortex-dependent perceptual task in which mice discriminate tactile gratings on the basis of orientation using only their whiskers. Multielectrode recordings in the barrel cortex reveal weak orientation tuning in average firing rates (500-ms time scale) during grating exploration despite high levels of cortical activity. Just before decision, orientation information extracted from fast cortical dynamics (100-ms time scale) more closely resembles concurrent psychophysical measurements than single neuron orientation tuning curves. This temporal code conveys both stimulus and choice/action-related information, suggesting that fast cortical dynamics during exploration of a tactile object both reflect the physical stimulus and affect the decision

Olfactory modulation of barrel cortex activity during active whisking and passive whisker stimulation

International audienceRodents depend on olfaction and touch to meet many of their fundamental needs. However, the impact of simultaneous olfactory and tactile inputs on sensory representations in the cortex remains elusive. To study these interactions, we recorded large populations of barrel cortex neurons using 2-photon calcium imaging in head-fixed mice during olfactory and tactile stimulation. Here we show that odors bidirectionally alter activity in a small but significant population of barrel cortex neurons through at least two mechanisms, first by enhancing whisking, and second by a central mechanism that persists after whisking is abolished by facial nerve sectioning. Odor responses have little impact on tactile information, and they are sufficient for decoding odor identity, while behavioral parameters like whisking, sniffing, and facial movements are not odor identity-specific. Thus, barrel cortex activity encodes specific olfactory information that is not linked with odor-induced changes in behavior

Deep imaging in the brainstem reveals functional heterogeneity in V2a neurons controlling locomotion

International audienceV2a neurons are a genetically defined cell class that forms a major excitatory descending pathway from the brainstem reticular formation to the spinal cord. Their activation has been linked to the termination of locomotor activity based on broad optogenetic manipulations. However, because of the difficulties involved in accessing brainstem structures for in vivo cell type–specific recordings, V2a neuron function has never been directly observed during natural behaviors. Here, we imaged the activity of V2a neurons using micro-endoscopy in freely moving mice. We find that as many as half of the V2a neurons are excited at locomotion arrest and with low reliability. Other V2a neurons are inhibited at locomotor arrests and/or activated during other behaviors such as locomotion initiation or stationary grooming. Our results establish that V2a neurons not only drive stops as suggested by bulk optogenetics but also are stratified into subpopulations that likely contribute to diverse motor patterns