1,505 research outputs found
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Lifestyle and health factors associated with progressing and remitting trajectories of untreated lower urinary tract symptoms among elderly men.
BackgroundKnowledge of factors associated with the course of lower urinary tract symptoms (LUTS) before treatment is needed to inform preventive interventions. In a prospective study of elderly men untreated for LUTS, we identified factors associated with symptom progression and remission.MethodsIn community-dwelling US men aged ≥65 years, the American Urological Association Symptom Index (AUA-SI) was repeated four times, once at baseline (2000-2002) and then every 2 years thereafter. Analyses included 1740 men with all four AUA-SI assessments, who remained free from diagnosed prostate cancer, and who reported no treatment for LUTS or BPH during follow-up that averaged 6.9 (±0.4) years. LUTS change was determined with group-based trajectory modelingof the repeated AUA-SI measures. Multivariable logistic regression was then used to determine the baseline factors associated with progressing compared with stable trajectories, and with remitting compared with progressing trajectories. Lifestyle, body mass index (BMI) (kg/m(2)), mobility, mental health (Short-Form 12), medical history and prescription medications were considered for selection. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated for variables in each model.ResultsWe identified 10 AUA-SI trajectories: 4 stable (1277 men, 73%), three progressing (345 men, 20%), two remitting (98 men, 6%) and one mixed (20 men, 1%). Men in progressing compared with stable trajectories were more likely to have mobility limitations (OR=2.0, 95% CI: 1.0-3.8), poor mental health (OR=1.9, 95% CI: 1.1-3.4), BMI≥25.0 kg m(-2) (OR=1.7, 95% CI: 1.0-2.8), hypertension (OR=1.5, 95% CI: 1.0-2.4) and back pain (OR=1.5, 95% CI: 1.0-2.4). Men in remitting compared with progressing trajectories more often used central nervous system medications (OR=2.3, 95% CI: 1.1-4.9) and less often had a history of problem drinking (OR=0.4, 95% CI: 0.2-0.9).ConclusionsSeveral non-urological lifestyle and health factors were independently associated with risk of LUTS progression in older men
Feasibility study of combined dynamic imaging and lymphaticovenous anastomosis surgery for breast cancer-related lymphoedema.
Background Breast cancer-related lymphoedema (BCRL) presents a significant healthcare burden and adversely affects quality of life of breast cancer survivors. A prospective feasibility study was performed on lymphaticovenous anastomosis (LVA) for the treatment of BCRL.Methods Patients with BCRL underwent near-infrared spectroscopy with indocyanine green lymphatic mapping to identify suitable lymphatic channels for LVA. End-to-end anastomoses to subdermal venules were performed and patients recommenced compression garment therapy (CGT) after surgery. Volumetric assessment of the affected limb was performed at regular intervals using infrared perometry to calculate the excess volume reduction.Results Over a 24-month interval, 27 patients with BCRL underwent LVA. The mean duration of lymphoedema was 3·5 (range 0·5-18) years, and the mean number of LVAs performed was 3 (range 2-5). Twenty-four of the 27 patients completed 12-month follow-up. Patients exhibited three patterns of volumetric response following LVA: sustained response (16 patients), transient response (5) or no response (6). Sustained responders showed an excess volume reduction of -33·2 per cent at 12 months, and this correlated positively with the number of LVAs performed (r = -0·56, P = 0·034). Overall, ten patients were able to downgrade CGT after surgery, and two patients were CGT-free at 12 months.Conclusion LVA resulted in a sustained volume reduction in selected patients and may offset the burden of CGT. Further work is required to identify biomarkers that predict a favourable response to LVA surgery
Vacuum Stability, Perturbativity, and Scalar Singlet Dark Matter
We analyze the one-loop vacuum stability and perturbativity bounds on a
singlet extension of the Standard Model (SM) scalar sector containing a scalar
dark matter candidate. We show that the presence of the singlet-doublet quartic
interaction relaxes the vacuum stability lower bound on the SM Higgs mass as a
function of the cutoff and lowers the corresponding upper bound based on
perturbativity considerations. We also find that vacuum stability requirements
may place a lower bound on the singlet dark matter mass for given singlet
quartic self coupling, leading to restrictions on the parameter space
consistent with the observed relic density. We argue that discovery of a light
singlet scalar dark matter particle could provide indirect information on the
singlet quartic self-coupling.Comment: 25 pages, 10 figures; v2 - fixed minor typos; v3 - added to text
discussions of other references, changed coloring of figures for easier black
and white viewin
Bridging Time Scales in Cellular Decision Making with a Stochastic Bistable Switch
Cellular transformations which involve a significant phenotypical change of
the cell's state use bistable biochemical switches as underlying decision
systems. In this work, we aim at linking cellular decisions taking place on a
time scale of years to decades with the biochemical dynamics in signal
transduction and gene regulation, occuring on a time scale of minutes to hours.
We show that a stochastic bistable switch forms a viable biochemical mechanism
to implement decision processes on long time scales. As a case study, the
mechanism is applied to model the initiation of follicle growth in mammalian
ovaries, where the physiological time scale of follicle pool depletion is on
the order of the organism's lifespan. We construct a simple mathematical model
for this process based on experimental evidence for the involved genetic
mechanisms. Despite the underlying stochasticity, the proposed mechanism turns
out to yield reliable behavior in large populations of cells subject to the
considered decision process. Our model explains how the physiological time
constant may emerge from the intrinsic stochasticity of the underlying gene
regulatory network. Apart from ovarian follicles, the proposed mechanism may
also be of relevance for other physiological systems where cells take binary
decisions over a long time scale.Comment: 14 pages, 4 figure
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The resilience of postglacial hunter-gatherers to abrupt climate change
Understanding the resilience of early societies to climate change is an essential part of exploring the environmental sensitivity of human populations. There is significant interest in the role of abrupt climate events as a driver of early Holocene human activity, but there are very few well-dated records directly compared with local climate archives. Here, we present evidence from the internationally important Mesolithic site of Star Carr showing occupation during the early Holocene, which is directly compared with a high-resolution palaeoclimate record from neighbouring lake beds. We show that-once established-there was intensive human activity at the site for several hundred years when the community was subject to multiple, severe, abrupt climate events that impacted air temperatures, the landscape and the ecosystem of the region. However, these results show that occupation and activity at the site persisted regardless of the environmental stresses experienced by this society. The Star Carr population displayed a high level of resilience to climate change, suggesting that postglacial populations were not necessarily held hostage to the flickering switch of climate change. Instead, we show that local, intrinsic changes in the wetland environment were more significant in determining human activity than the large-scale abrupt early Holocene climate events
Divergent mathematical treatments in utility theory
In this paper I study how divergent mathematical treatments affect mathematical modelling, with a special focus on utility theory. In particular I examine recent work on the ranking of information states and the discounting of future utilities, in order to show how, by replacing the standard analytical treatment of the models involved with one based on the framework of Nonstandard Analysis, diametrically opposite results are obtained. In both cases, the choice between the standard and nonstandard treatment amounts to a selection of set-theoretical parameters that cannot be made on purely empirical grounds. The analysis of this phenomenon gives rise to a simple logical account of the relativity of impossibility theorems in economic theory, which concludes the paper
Diagnostic accuracy of existing methods for identifying diabetic foot ulcers from inpatient and outpatient datasets
<p>Abstract</p> <p>Background</p> <p>As the number of persons with diabetes is projected to double in the next 25 years in the US, an accurate method of identifying diabetic foot ulcers in population-based data sources are ever more important for disease surveillance and public health purposes. The objectives of this study are to evaluate the accuracy of existing methods and to propose a new method.</p> <p>Methods</p> <p>Four existing methods were used to identify all patients diagnosed with a foot ulcer in a Department of Veterans Affairs (VA) hospital from the inpatient and outpatient datasets for 2003. Their electronic medical records were reviewed to verify whether the medical records positively indicate presence of a diabetic foot ulcer in diagnoses, medical assessments, or consults. For each method, five measures of accuracy and agreement were evaluated using data from medical records as the gold standard.</p> <p>Results</p> <p>Our medical record reviews show that all methods had sensitivity > 92% but their specificity varied substantially between 74% and 91%. A method used in Harrington et al. (2004) was the most accurate with 94% sensitivity and 91% specificity and produced an annual prevalence of 3.3% among VA users with diabetes nationwide. A new and simpler method consisting of two codes (707.1× and 707.9) shows an equally good accuracy with 93% sensitivity and 91% specificity and 3.1% prevalence.</p> <p>Conclusions</p> <p>Our results indicate that the Harrington and New methods are highly comparable and accurate. We recommend the Harrington method for its accuracy and the New method for its simplicity and comparable accuracy.</p
Guidance on stakeholder engagement practices to inform the development of areawide vector control methods
This is the final version. Available from the publisher via the DOI in this record.British Academ
Targeted analysis of four breeds narrows equine Multiple Congenital Ocular Anomalies locus to 208 kilobases
The syndrome Multiple Congenital Ocular Anomalies (MCOA) is the collective name ascribed to heritable congenital eye defects in horses. Individuals homozygous for the disease allele (MCOA phenotype) have a wide range of eye anomalies, while heterozygous horses (Cyst phenotype) predominantly have cysts that originate from the temporal ciliary body, iris, and/or peripheral retina. MCOA syndrome is highly prevalent in the Rocky Mountain Horse but the disease is not limited to this breed. Affected horses most often have a Silver coat color; however, a pleiotropic link between these phenotypes is yet to be proven. Locating and possibly isolating these traits would provide invaluable knowledge to scientists and breeders. This would favor maintenance of a desirable coat color while addressing the health concerns of the affected breeds, and would also provide insight into the genetic basis of the disease. Identical-by-descent mapping was used to narrow the previous 4.6-Mb region to a 264-kb interval for the MCOA locus. One haplotype common to four breeds showed complete association to the disease (Cyst phenotype, n = 246; MCOA phenotype, n = 83). Candidate genes from the interval, SMARCC2 and IKZF4, were screened for polymorphisms and genotyped, and segregation analysis allowed the MCOA syndrome region to be shortened to 208 kb. This interval also harbors PMEL17, the gene causative for Silver coat color. However, by shortening the MCOA locus by a factor of 20, 176 other genes have been unlinked from the disease and only 15 genes remain
Priority for the Worse Off and the Social Cost of Carbon
The social cost of carbon (SCC) is a monetary measure of the harms from carbon emission. Specifically, it is the reduction in current consumption that produces a loss in social welfare equivalent to that caused by the emission of a ton of CO2. The standard approach is to calculate the SCC using a discounted-utilitarian social welfare function (SWF)—one that simply adds up the well-being numbers (utilities) of individuals, as discounted by a weighting factor that decreases with time. The discounted-utilitarian SWF has been criticized both for ignoring the distribution of well-being, and for including an arbitrary preference for earlier generations. Here, we use a prioritarian SWF, with no time-discount factor, to calculate the SCC in the integrated assessment model RICE. Prioritarianism is a well-developed concept in ethics and theoretical welfare economics, but has been, thus far, little used in climate scholarship. The core idea is to give greater weight to well-being changes affecting worse off individuals. We find substantial differences between the discounted-utilitarian and non-discounted prioritarian SCC
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