2,303 research outputs found
Correlation between crime and vegetation : a case study of Jefferson County, Kentucky.
Conflicting evidence exists about environmental determinants of crime. While scholars agree there is a relationship between environmental factors and crime, there is not consistency among measures of associations. Looking specifically at the influence of vegetation, there is disagreement as to whether vegetation promotes or deters crime. Some studies show criminals use vegetation as a tool to conceal themselves, while others show vegetation serves as a territory marker, which discourages criminals. My research explores these factors within Jefferson County, Kentucky’s largest and most urban, using NDVI as a proxy for vegetation cover and spatially explicit crime densities aggregated to the census block group level. Of over 30 types of crime, I subset crimes to those that tend to occur outdoors: assault, auto theft, burglary, robbery, and theft. Percent of occupied houses, percent owned/mortgaged houses, median age, per capita income, educational attainment, population density and percent in poverty were considered as potentially cofounding aspects of this relationship. The explanatory power of vegetation in regards to crime density was tested using multivariate ordinary least squares regression. The study found that even after accounting for other socioeconomic factors, crime and vegetation have a statistically significant negative relationship. This research provides evidence in exploring the influence of vegetation on crime and, combined with ongoing research into criminal motivations, provides insight into how vegetation conditions might better be included in managing crime in urban areas
An Index for Measuring Community Resilience to Flooding in Baton Rouge, Louisiana
The greater Baton Rouge area in Louisiana has been impacted by repeated floods throughout its history. The most recent flood in August 2016 resulted in damages to over 80,000 homes and businesses and upwards of $430 million in public assistance granted by the Federal Emergency Management Agency. East Baton Rouge Parish and neighboring Livingston and Ascension parishes are expected to face compounded pressures and risks with the threat of increasing frequency of flood events coupled with expanding populations due to continuing suburbanization and inland migration from those living on Louisiana\u27s coast. The purpose of this research is to create and validate an index to measure community resilience to flooding across Ascension, East Baton Rouge, and Livingston parishes from 1983- 2016. Using a combination of environmental and socioeconomic variables, the index is applied to three different years where historic and devastating flooding has occurred in the region: 1983, 1993, and 2016. A brief history of suburban sprawl, flood mitigation strategies, and land use changes provides a framework to measure the efficacy of the index. This historic perspective allows for a better understanding of how capacity for building resilience has evolved, and how we might expect it to progress in the future. This research helps understand how community resilience has changed over time after repeated flood events. Furthermore, this will help quantify the components that lend themselves to community resilience, so that future natural hazards may be recognized and their harmful effects may be mitigated
Effective gauge group of pure loop quantum gravity is SO(3): New estimate of the Immirzi parameter
We argue that the effective gauge group for {\it pure} four-dimensional loop
quantum gravity(LQG) is SO(3) (or ) instead of SU(2) (or ).
As a result, links with half-integer spins in spin network states are not
realized for {\it pure} LQG, implying a modification of the spectra of area and
volume operators. Our observations imply a new value of
for the Immirzi parameter which is obtained from matching the
Bekenstein-Hawking entropy to the number of states from LQG calculations.
Moreover, even if the dominant contribution to the entropy is not assumed to
come from configurations with the minimum spins, the results of both pure LQG
and the supersymmetric extension of LQG can be made compatible when only
integer spins are realized for the former, while the latter also contains
half-integer spins, together with an Immirzi parameter for the supersymmetric
case which is twice the value of the SO(3) theory. We also verify that the
coefficient of logarithmic correction to the Bekenstein-Hawking
entropy formula is robust, independent of whether only integer, or also
half-integer spins, are realized.Comment: new value of Immirzi parameter is ~0.170; dominance of miminum spin
configurations is not assumed in comparing with Bekenstein-Hawking formula;
typos corrected. Version pressed in PL
The role of neuronal NLRP1 inflammasome in Alzheimer's disease : bringing neurons into the neuroinflammation game
The innate immune system and inflammatory response in the brain have critical impacts on the pathogenesis of many neurodegenerative diseases including Alzheimer’s disease (AD). In the central nervous system (CNS), the innate immune response is primarily mediated by microglia. However, non-glial cells such as neurons could also partake in inflammatory response independently through inflammasome signalling. The NLR family pyrin domain-containing 1 (NLRP1) inflammasome in the CNS is primarily expressed by pyramidal neurons and oligodendrocytes. NLRP1 is activated in response to amyloid-β (Aβ) aggregates, and its activation subsequently cleaves caspase-1 into its active subunits. The activated caspase-1 proteolytically processes interleukin-1β (IL-1β) and interleukin-18 (IL-18) into maturation whilst co-ordinately triggers caspase-6 which is responsible for apoptosis and axonal degeneration. In addition, caspase-1 activation induces pyroptosis, an inflammatory form of programmed cell death. Studies in murine AD models indicate that the Nlrp1 inflammasome is indeed upregulated in AD and neuronal death is observed leading to cognitive decline. However, the mechanism of NLRP1 inflammasome activation in AD is particularly elusive, given its structural and functional complexities. In this review, we examine the implications of the human NLRP1 inflammasome and its signalling pathways in driving neuroinflammation in AD
Procalcitonin as a marker of bacterial infection in the emergency department: an observational study
INTRODUCTION: Procalcitonin (PCT) has been proposed as a marker of infection in critically ill patients; its level is related to the severity of infection. We evaluated the value of PCT as a marker of bacterial infection for emergency department patients. METHODS: This prospective observational study consecutively enrolled 120 adult atraumatic patients admitted through the emergency department of a 3000-bed tertiary university hospital in May 2001. Fifty-eight patients were infected and 49 patients were not infected. The white blood cell counts, the serum C-reactive protein (CRP) level (mg/l), and the PCT level (ng/ml) were compared between the infected and noninfected groups of patients. RESULTS: A white blood cell count >12,000/mm(3 )or <4000/mm(3 )was present in 36.2% of the infected patients and in 18.4% of the noninfected patients. The best cut-off serum levels for PCT and CRP, identified using the Youden's Index, were 0.6 ng/ml and 60 mg/l, respectively. Compared with CRP, PCT had a comparable sensitivity (69.5% versus 67.2%), a lower specificity (64.6% versus 93.9%), and a lower area under the receiver operating characteristic curve (0.689 versus 0.879). PCT levels, but not CRP levels, were significantly higher in bacteremic and septic shock patients. Multivariate logistic regression identified that a PCT level ≥ 2.6 ng/ml was independently associated with the development of septic shock (odds ratio, 38.3; 95% confidence interval, 5.6–263.5; P < 0.001). CONCLUSIONS: PCT is not a better marker of bacterial infection than CRP for adult emergency department patients, but it is a useful marker of the severity of infection
Strenuous physical activity, exercise, and pelvic organ prolapse : a narrative scoping review
Introduction and hypothesis
High-intensity physical activity and exercise have been listed as possible risk factors for pelvic organ prolapse (POP). The aim of the present study is to conduct a literature review on the prevalence and incidence of POP in women who engage in regular physical activity. In addition, we review the effects of a single exercise or a single session of exercise on pelvic floor support. Finally, the effect of exercises on POP in the early postpartum period is reviewed.
Methods
This is a narrative scoping review. We searched PubMed and Ovid Medline, the Physiotherapy Evidence Database (PEDro), and the Cochrane Database of Systematic Reviews up to May 2022 with the following MeSH terms: “physical activity” AND “exercise” AND “pelvic floor” AND “pelvic organ prolapse”.
Results
Eight prevalence studies were retrieved. Prevalence rates of symptomatic POP varied between 0 (small study within different sports) and 23% (Olympic weightlifters and power lifters). Parity was the only factor associated with POP in most studies. Three studies evaluated the pelvic floor after a single exercise or one session of exercise and found increased vaginal descent or increased POP symptoms. One prospective cohort study reported the development of POP after 6 weeks of military parashot training, and one randomized trial reported increased POP symptoms after transverse abdominal training. There is scant knowledge on exercise and POP in the postpartum period.
Conclusions
Prevalence of POP in sports varies widely. Experimental and prospective studies indicate that strenuous exercise increased POP symptoms and reduced pelvic floor support
Are hypopressive and other exercise programs efective for the treatment of pelvic organ prolapse?
Introduction and hypothesis
Pelvic floor muscle training (PFMT) is effective for the treatment of pelvic organ prolapse (POP), but other exercise programs have also been promoted and used. The aim of this review was to evaluate the effect of hypopressive and other exercise programs besides PFMT for POP.
Methods
A literature search was conducted on Ovid Medline, EMBASE, CINAHL, Cochrane, PEDro, and Scopus databases from January 1996 to 30 December 2021. Only randomized controlled trials (RCTs) were included. The keywords were combinations of “pelvic organ prolapse” or “urogenital prolapse,” and “exercise therapy,” “hypopressive exercise,” “Kegel,” “pelvic floor muscle training,” “pelvic floor muscle exercises,” “Pilates,” “treatment,” “yoga,” “Tai Chi.” Methodological quality was assessed using the PEDro rating scale (0–10).
Results
Seven RCTs containing hypopressive exercise, yoga or breathing and hip muscle exercises in an inverted position were retrieved and analyzed. PEDro score ranged from 4 to 7. There was no additional effect of adding hypopressive exercise to PFMT, and PFMT was more effective than hypopressive exercise alone. The studies that included the term “yoga” included regular PFMT and thus can be classified as PFMT. Hip exercises in an inverted position added to PFMT vs PFMT alone showed better improvement in some secondary outcomes but not in the primary outcome, POP stage.
Conclusions
There are few RCTs assessing the effects of other exercise programs besides PFMT in the treatment of POP. To date, there is no evidence that other exercise programs are more effective than PFMT for POP
Even-Odd Layer-Dependent Anomalous Hall Effect in Topological Magnet MnBi2Te4 Thin Films
A central theme in condensed matter physics is to create and understand the
exotic states of matter by incorporating magnetism into topological materials.
One prime example is the quantum anomalous Hall (QAH) state. Recently, MnBi2Te4
has been demonstrated to be an intrinsic magnetic topological insulator and the
QAH effect was observed in exfoliated MnBi2Te4 flakes. Here, we used molecular
beam epitaxy (MBE) to grow MnBi2Te4 films with thickness down to 1 septuple
layer (SL) and performed thickness-dependent transport measurements. We
observed a non-square hysteresis loop in the antiferromagnetic state for films
with thickness greater than 2 SL. The hysteresis loop can be separated into two
AH components. Through careful analysis, we demonstrated that one AH component
with the larger coercive field is from the dominant MnBi2Te4 phase, while the
other AH component with the smaller coercive field is from the minor Mn-doped
Bi2Te3 phase in the samples. The extracted AH component of the MnBi2Te4 phase
shows a clear even-odd layer-dependent behavior, a signature of
antiferromagnetic thin films. Our studies reveal insights on how to optimize
the MBE growth conditions to improve the quality of MnBi2Te4 films, in which
the QAH and other exotic states are predicted.Comment: 23 pages, 4 figures, comments are welcom
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