Voice Onset Time Production In Individuals Wth Alzheimer\u27s Disease

In the present study, voice onset time (VOT) measurements were compared between a group of individuals with moderate Alzheimer\u27s disease (AD) and a group of healthy age- and gender-matched peers. Participants read a list of consonant-vowel-consonant (CVC) words, which included the six stop consonants. Recordings were gathered and digitized. The VOT measurements were made from oscillographic displays obtained from the Brown Laboratory Interactive Speech System (BLISS) implemented on an IBM-compatible computer. VOT measures for the participants\u27 six stop consonant productions were subjected to statistical analysis. The results of the study indicated that differences in VOT values were not statistically significant in the speakers with Alzheimer\u27s disease from the normal control speakers

Temporal order processing of syllables in the left parietal lobe

Speech processing requires the temporal parsing of syllable order. Individuals suffering from posterior left hemisphere brain injury often exhibit temporal processing deficits as well as language deficits. Although the right posterior inferior parietal lobe has been implicated in temporal order judgments (TOJs) of visual information, there is limited evidence to support the role of the left inferior parietal lobe (IPL) in processing syllable order. The purpose of this study was to examine whether the left inferior parietal lobe is recruited during temporal order judgments of speech stimuli. Functional magnetic resonance imaging data were collected on 14 normal participants while they completed the following forced-choice tasks: (1) syllable order of multisyllabic pseudowords, (2) syllable identification of single syllables, and (3) gender identification of both multisyllabic and monosyllabic speech stimuli. Results revealed increased neural recruitment in the left inferior parietal lobe when participants made judgments about syllable order compared with both syllable identification and gender identification. These findings suggest that the left inferior parietal lobe plays an important role in processing syllable order and support the hypothesized role of this region as an interface between auditory speech and the articulatory code. Furthermore, a breakdown in this interface may explain some components of the speech deficits observed after posterior damage to the left hemisphere

Evaluation of the paraphyletic assemblages within Lonchophyllinae, with description of a new tribe and genus

In the past decade, six new species and one new genus have been described in the Lonchophyllinae (Chiroptera: Phyllostomidae), increasing the number of recognized taxa in the subfamily to four genera and 17 species. During this time, three studies, both morphologic and genetic, indicated the genus Lonchophylla was paraphyletic with respect to other genera in the subfamily. Using tissues from museum voucher specimens, including the holotypes of specimens of Xeronycteris vieirai and Lonchophylla pattoni, issues related to the previous paraphyletic assemblages were addressed. A combination of mitochondrial (Cytb), nuclear data (Fgb-I7, TSHB-I2), chromosome diploid and fundamental numbers, and morphologic characters was used to determine whether all species of Lonchophylla share a common ancestor after diverging from other genera in the subfamily. Based on gene sequence data, a basal, monophyletic, statistically supported radiation within the subfamily Lonchophyllinae was observed in all phylogenetic analyses. We conclude that this assemblage merits recognition as a new tribe and genus, and, therefore, present formal descriptions of the genus as Hsunycteris and the tribe as Hsunycterini. Several other issues related to paraphyly within both the genus Hsunycteris and tribe Lonchophyllini were not resolvable at this time, including that the genus Lonchophylla is paraphyletic and Hsunycteris thomasi contains four genetic species. A species in the genus Hsunycteris remains undescribed because it was not possible to determine which of two lineages the type specimen of H. thomasi is actually a member. Until additional genetic and/or morphologic data are available, resolution of all paraphyletic relationships is not possible. Future studies that focus on utilizing morphologic and genetic (both mitochondrial and nuclear) data from the type specimens of species of Lonchophylla and species of Hsunycteris thomasi are needed to resolve these remaining questions

An Improved Trajectory Model to Evaluate the Collection Performance of Snow Gauges

Recent studies have used numerical models to estimate the collection efficiency\ud of solid precipitation gauges when exposed to the wind, in both\ud shielded and unshielded configurations. The models used computational fluid\ud dynamics (CFD) simulations of the airflow pattern generated by the aerodynamic\ud response to the gauge/shield geometry. These are used as initial conditions\ud to perform Lagrangian tracking of solid precipitation particles. Validation\ud of the results against field observations yielded similarities in the overall\ud behavior, but the model output only approximately reproduced the dependence\ud of the experimental collection efficiency on wind speed. This paper\ud presents an improved snowflake trajectory modeling scheme due to the inclusion\ud of a dynamically-determined drag coefficient. The drag coefficient\ud was estimated using the local Reynolds number as derived from CFD simulations\ud within a time-independent Reynolds Averaged Navier-Stokes (RANS)\ud approach. The proposed dynamic model greatly improves the consistency of\ud results with the field observations recently obtained at the Marshall, CO Winter\ud Precipitation Testbed

Cerebral perfusion in chronic stroke: Implications for lesion-symptom mapping and functional MRI

Lesion-symptom mapping studies are based upon the assumption that behavioral impairments are directly related to structural brain damage. Given what is known about the relationship between perfusion deficits and impairment in acute stroke, attributing specific behavioral impairments to localized brain damage leaves room for speculation, as impairments could also reflect abnormal neurovascular function in brain regions that appear structurally intact on traditional CT and MRI scans. Compared to acute stroke, the understanding of cerebral perfusion in chronic stroke is far less clear. Utilizing arterial spin labeling (ASL) MRI, we examined perfusion in 17 patients with chronic left hemisphere stroke. The results revealed a decrease in left hemisphere perfusion, primarily in peri-infarct tissue. There was also a strong relationship between increased infarct size and decreased perfusion. These findings have implications for lesion-symptom mapping studies as well as research that relies on functional MRI to study chronic stroke

Deciphering endothelial heterogeneity in health and disease at single cell resolution: progress and perspectives

Endothelial cells (ECs) constitute the inner lining of vascular beds in mammals and are crucial for homeostatic regulation of blood vessel physiology, but also play a key role in pathogenesis of many diseases, thereby representing realistic therapeutic targets. However, it has become evident that ECs are heterogeneous, encompassing several subtypes with distinct functions, which makes EC targeting and modulation in the disease-context challenging. The rise of the new single cell era has led to an emergence of studies aimed at interrogating transcriptome diversity along the vascular tree, and has revolutionized our understanding of EC heterogeneity from both a physiological and pathophysiological context. Here, we discuss recent landmark studies aimed at teasing apart the heterogeneous nature of ECs. We cover driving (epi)genetic, transcriptomic and metabolic forces underlying EC heterogeneity in health and disease, as well as current strategies used to combat disease-enriched EC phenotypes, and propose strategies to transcend largely descriptive heterogeneity towards prioritization and functional validation of therapeutically targetable drivers of EC diversity. Lastly, we provide an overview of the most recent advances and hurdles in single EC OMICs

State of the field: digital history

Computing and the use of digital sources and resources is an everyday and essential practice in current academic scholarship. The present article gives a concise overview of approaches and methods within digital historical scholarship, focussing on the question: How have the Digital Humanities evolved and what has that evolution brought to historical scholarship? We begin by discussing techniques in which data are generated and machine searchable, such as OCR/HTR, born-digital archives, computer vision, scholarly editions, and Linked Data. In the second section, we provide examples of how data is made more accessible through quantitative text and network analysis. We close with a section on the need for hermeneutics and data-awareness in digital historical scholarship. The technologies described in this article have had varying degrees of effect on historical scholarship, usually in indirect ways. For example, technologies such as OCR and search engines may not be directly visible in a historical argument; however, these technologies do shape how historians interact with sources and whether sources can be accessed at all. It is with this article that we aim to start to take stock of the digital approaches and methods used in historical scholarship which may serve as starting points for scholars to understand the digital turn in the field and how and when to implement such approaches in their work

Airway glucose concentrations and effect on growth of respiratory pathogens in cystic fibrosis

AbstractBackgroundPulmonary decline accelerates in cystic fibrosis-related diabetes (CFRD) proportional to severity of glucose intolerance, but mechanisms are unclear. In people without CF, airway glucose (AG) concentrations are elevated when blood glucose (BG)≥8 mmol L−1 (airway threshold), and are associated with acquisition of respiratory infection.MethodsTo determine the relationship between BG and AG, 40 CF patients underwent paired BG and AG (nasal) measurements. Daily time with BG>airway threshold was compared in 10 CFRD, 10 CF patients with normal glucose tolerance (CF-NGT) and 10 healthy volunteers by continuous BG monitoring. The effect of glucose at airway concentrations on bacterial growth was determined in vitro by optical densitometry.ResultsAG was present more frequently (85%-vs.-19%, p<0.0001) and at higher concentrations (0.5–3 mmol L−1-vs.-0.5–1 mmol L−1, p<0.0001) when BG was ≥8 mmol L−1-vs.-<8 mmol L−1. Daily time with BG≥8 mmol L−1 was CFRD (49±25%), CF-NGT (6±5%), healthy volunteers (1±3%), p<0.0001. Staphylococcus aureus growth increased at ≥0.5 mmol L−1 (p=0.006) and Pseudomonas aeruginosa growth above 1–4 mmol L−1 glucose (p=0.039).ConclusionsBG≥8 mmol L−1 predicted elevated AG concentrations in CF, at least in nasal secretions. CFRD patients spent ∼ 50% day with BG>airway threshold, implying persistently elevated AG concentrations. Further studies are required to determine whether elevated airway glucose concentrations contribute to accelerated pulmonary decline in CFRD

Training the workforce in evidence-based public health: An evaluation of impact among US and international practitioners

INTRODUCTION: The Prevention Research Center in St. Louis developed a course on evidence-based public health in 1997 to train the public health workforce in implementation of evidence-based public health. The objective of this study was to assess use and benefits of the course and identify barriers to using evidence-based public health skills as well as ways to improve the course. METHODS: We used a mixed-method design incorporating on-site pre- and post-evaluations among US and international course participants who attended from 2008 through 2011 and web-based follow-up surveys among course participants who attended from 2005 through 2011 (n = 626). Respondents included managers, specialists, and academics at state health departments, local health departments, universities, and national/regional health departments. RESULTS: We found significant improvement from pre- to post-evaluation for 11 measures of knowledge, skill, and ability. Follow-up survey results showed at least quarterly use of course skills in most categories, majority endorsement of most course benefits, and lack of funding and coworkers who do not have evidence-based public health training as the most significant barriers to implementation of evidence-based public health. Respondents suggested ways to increase evidence-based decision making at their organization, focusing on organizational support and continued access to training. CONCLUSION: Although the evidence-based public health course is effective in improving self-reported measures of knowledge, skill, and ability, barriers remain to the implementation of evidence-based decision making, demonstrating the importance of continuing to offer and expand training in evidence-based public health

Bactericidal activities and post-antibiotic effects of ofloxacin and ceftriaxone against drug-resistant Salmonella enterica serovar Typhi.

BACKGROUND: The clinical response to ceftriaxone in patients with typhoid fever is significantly slower than with ofloxacin, despite infection with Salmonella enterica serovar Typhi (S. Typhi) isolates with similar susceptibilities (MIC 0.03-0.12 mg/L). The response to ofloxacin is slower if the isolate has intermediate susceptibility (MIC 0.25-1.0 mg/L). OBJECTIVES: To determine the bactericidal activity and post-antibiotic effect (PAE) of ceftriaxone and ofloxacin against S. Typhi. METHODS: The mean time to reach a 99.9% reduction in log10 count (bactericidal activity) and PAE of ceftriaxone and ofloxacin were determined for 18 clinical isolates of S. Typhi in time-kill experiments (MIC range for ofloxacin 0.06-1.0 mg/L and for ceftriaxone 0.03-0.12 mg/L). RESULTS: The mean (SD) bactericidal activity of ofloxacin was 33.1 (15.2) min and 384.4 (60) min for ceftriaxone. After a 30 min exposure to ofloxacin, the mean (SD) duration of PAE was 154.7 (52.6) min. There was no detectable PAE after 1 h of exposure to ceftriaxone. For ofloxacin, bactericidal activity and PAE did not significantly differ between isolates with full or intermediate susceptibility provided ofloxacin concentrations were maintained at 4×MIC. CONCLUSIONS: Infections with S. Typhi with intermediate ofloxacin susceptibility may respond to doses that maintain ofloxacin concentrations at 4×MIC at the site of infection. The slow bactericidal activity of ceftriaxone and absent PAE may explain the slow clinical response in typhoid