6,322 research outputs found
Weighted and unweighted network of amino acids within protein
The information regarding the structure of a single protein is encoded in the
network of interacting amino acids. Considering each protein as a weighted and
unweighted network of amino acids we have analyzed a total of forty nine
protein structures that covers the three branches of life on earth. Our results
show that the probability degree distribution of network connectivity follows
Poisson's distribution; whereas the probability strength distribution does not
follow any known distribution. However, the average strength of amino acid node
depends on its degree (k). For some of the proteins, the strength of a node
increases linearly with k. On the other hand, for a set of other proteins,
although the strength increases linaerly with k for smaller values of k, we
have not obtained any clear functional relationship of strength with degree at
higher values of k. The results also show that the weight of the amino acid
nodes belonging to the highly connected nodes tend to have a higher value. The
result that the average clustering coefficient of weighted network is less than
that of unweighted network implies that the topological clustering is generated
by edges with low weights. The ratio of average clustering coefficients of
protein network to that of the corresponding classical random network varies
linearly with the number (N) of amino acids of a protein; whereas the ratio of
characteristic path lengths varies logarithmically with N. The power law
behaviour of clustering coefficients of weighted and unweighted network as a
function of degree k indicates that the network has a signature of hierarchical
network. It has also been observed that the network is of assortative type
A Lesson from COVID-19 in the Importance of Sex Disaggregated Data: Sex Differences in SARS-CoV-2 Infection and Mortality Rates
Background: Emerging surveillance data from the COVID 19 pandemic suggest better outcomes in women.
Objective: This analysis aims to determine the magnitude of sex differences in SARS-CoV-2 infection rates and survival at a country level.
Methods: Data was sourced from the Global Health 50/50 (GH 50/50) website https://globalhealth5050.org/covid19, housed at University College of London, which collects government reported national surveillance data on confirmed cases of COVID 19 and confirmed deaths. This analysis used data completely disaggregated by sex, cutoff date 5/8/2020.
Results: Of 78 countries, with 3,044,513 confirmed cases of COVID 19 and 181,742 deaths, data were completely disaggregated by sex in 36 countries, partially disaggregated in 26, and not disaggregated in 16. In countries, with completely disaggregated data, 1,240, 803 cases of COVID-19 were reported on May 3, 4, 5 or 6, 2020 in 31 countries, and between Feb 28 and April 28 in 5 countries. The average proportion of cases in women was 50.3%: range 22% (Pakistan) to 63% (Netherlands). Deaths were reported in 83,388 individuals. The mean proportion of deaths in women was 39.2% (range 20% to 53%). The mean ratio of deaths (men to women) was 1.62 (range 0.9 to 3.2).
Discussion: This analysis of surveillance data from 36 countries shows a sex difference in mortality from COVID-19, with men more likely to die than women. Possible explanations include sex differences in the immune system, gender differences in environmental exposures or access to healthcare, and differences in comorbidities. Additional research to assess potential causes, and collect and analyze data by age, race, and ethnicity as well as sex and gender would be of value. These observations highlight the importance of disaggregating data by sex and gender in order to understand disease susceptibility, prevalence, and outcomes.https://jdc.jefferson.edu/sexandgenderhealth/1017/thumbnail.jp
Efficacy and Safety of Vibegron for the Treatment of Overactive Bladder in Women: A Subgroup Analysis From the Double-Blind, Randomized, Controlled EMPOWUR Trial
Importance The international phase 3 EMPOWUR trial demonstrated efficacy and safety of vibegron, a newer b3-adrenergic receptor agonist, in adults with overactive bladder (OAB). Women are disproportionately affected by OAB, especially those with bothersome symptoms, such as urge urinary incontinence (UUI). Objective This subgroup analysis from EMPOWUR assessed efficacy and safety of vibegron in women. Study Design In EMPOWUR, patients with OAB were randomized 5:5:4 to 12 weeks of treatment with once-daily vibegron 75 mg, placebo, or tolterodine 4-mg extended release. Efficacy end points included change from baseline at week 12 in mean daily number of micturitions, UUI episodes, and urgency episodes. Safety was assessed through adverse events (AEs). Results Of the patients included in the analysis, 1286 (84.9%) were women (vibegron, n = 463; placebo, n = 459; tolterodine, n = 364). At week 12, women receiving vibegron showed significant reductions (95% confidence intervals of least squares mean differences does not include 0) from baseline versus placebo in mean daily micturitions, UUI episodes, and urgency episodes, with least squares mean differences (95% confidence intervals) of −0.5 (−0.8 to −0.2), −0.7 (−1.0 to −0.4), and −0.8 (−1.3 to −0.4), respectively. Treatment-emergent AE incidence was similar with vibegron (39%) and placebo (35%); the most common AE with incidence higher with vibegron (4.3%) than placebo (2.6%) was headache. Conclusions In this subgroup analysis, women receiving vibegron showed significant reductions in key efficacy end points versus placebo and favorable safety profile, consistent with the overall results from EMPOWUR, suggesting that vibegron is efficacious and safe for the treatment of OAB in this patient population
A N A L Y S I S A N D C O M M E N T A R Y Revenge Pornography: Mental Health Implications and Related Legislation
Network 'small-world-ness': a quantitative method for determining canonical network equivalence
Background: Many technological, biological, social, and information networks fall into the broad class of 'small-world' networks: they have tightly interconnected clusters of nodes, and a shortest mean path length that is similar to a matched random graph (same number of nodes and edges). This semi-quantitative definition leads to a categorical distinction ('small/not-small') rather than a quantitative, continuous grading of networks, and can lead to uncertainty about a network's small-world status. Moreover, systems described by small-world networks are often studied using an equivalent canonical network model-the Watts-Strogatz (WS) model. However, the process of establishing an equivalent WS model is imprecise and there is a pressing need to discover ways in which this equivalence may be quantified.
Methodology/Principal Findings: We defined a precise measure of 'small-world-ness' S based on the trade off between high local clustering and short path length. A network is now deemed a 'small-world' if S. 1-an assertion which may be tested statistically. We then examined the behavior of S on a large data-set of real-world systems. We found that all these systems were linked by a linear relationship between their S values and the network size n. Moreover, we show a method for assigning a unique Watts-Strogatz (WS) model to any real-world network, and show analytically that the WS models associated with our sample of networks also show linearity between S and n. Linearity between S and n is not, however, inevitable, and neither is S maximal for an arbitrary network of given size. Linearity may, however, be explained by a common limiting growth process.
Conclusions/Significance: We have shown how the notion of a small-world network may be quantified. Several key properties of the metric are described and the use of WS canonical models is placed on a more secure footing
Provider reimbursement following the Affordable Care Act
Decreasing healthcare expenditure has been one of the main objectives of the Affordable Care Act (ACA). To achieve this goal, the Centers for Medicare and Medicaid Services (CMS) has been tasked with experimenting with provider reimbursement methods in an attempt to increase quality, while decreasing costs. The purpose of this research was to study the effects of the ACA on physician reimbursement rates from CMS to determine the most cost effective method of delivering healthcare services. CMS has experimented with payment methods in an attempt to increase cost effectiveness. Medicare has offered shared cost savings incentives to reward quality care to both primary care providers and preventative services. CMS has determined fee-for- service payments obsolete, opting instead for a Value Based Purchasing (VBP) method of payment. Although a universal payment method has yet to be adopted, it has been evident that a VBP model and preventative care can be used to decrease healthcare expenditure
Change over time in brain serotonin transporter binding in major depression: effects of therapy measured with [(123) I]-ADAM SPECT.
Several studies have reported low brain serotonin transporter (SERT) binding in individuals with major depression. We hypothesized that the SERT standardized uptake ratio (SUR) values using [(123) I]-ADAM single photon emission computed tomography would increase in depressed subjects who responded to cognitive behavior therapy (CBT) compared to CBT nonresponders. [(123) I]-ADAM scans were acquired before and after 12 weeks of CBT from 20 depressed subjects and on two occasions 12 weeks apart from 10 nondepressed, healthy volunteers. The primary outcome measure was change over time in SUR values in the midbrain, medial temporal lobe, and basal ganglia regions. Depressed subjects demonstrated low pretreatment mean SUR values that significantly increased over time in the midbrain (P = .011), right medial temporal lobe (P = .008), and left medial temporal lobe (P = .000) regions. Treatment responders showed a significant increase over time in SUR values in left medial temporal lobe (P = .029) and right medial temporal lobe (P = .007) regions. Partial and nonresponder subjects also showed a significant increase over time in SUR values in the left medial temporal region (P = .040) (vs. healthy volunteers), but to a lesser degree. The findings suggest that low pretreatment SERT binding may increase over time in some depressed individuals who experience symptom improvement
A Primary Care Approach to the Use and Interpretation of Common Rheumatologic Tests
The results of common rheumatologic laboratory tests play an important part in the diagnosis and management of rheumatic diseases. Rheumatologic test results can often be ambiguous and can sometimes be misleading, particularly in primary care settings. Because the diagnosis of most rheumatic conditions depends on information derived from sources other than serum tests, these laboratory values are usually supportive rather than diagnostic Studies suggest that primary care physicians overuse common rheumatologic test
The topology of a discussion: the #occupy case
We analyse a large sample of the Twitter activity developed around the social
movement 'Occupy Wall Street' to study the complex interactions between the
human communication activity and the semantic content of a discussion. We use a
network approach based on the analysis of the bipartite graph @Users-#Hashtags
and of its projections: the 'semantic network', whose nodes are hashtags, and
the 'users interest network', whose nodes are users In the first instance, we
find out that discussion topics (#hashtags) present a high heterogeneity, with
the distinct role of the communication hubs where most the 'opinion traffic'
passes through. In the second case, the self-organization process of users
activity leads to the emergence of two classes of communicators: the
'professionals' and the 'amateurs'. Moreover the network presents a strong
community structure, based on the differentiation of the semantic topics, and a
high level of structural robustness when a certain set of topics are censored
and/or accounts are removed. Analysing the characteristics the @Users-#Hashtags
network we can distinguish three phases of the discussion about the movement.
Each phase corresponds to specific moment of the movement: from declaration of
intent, organisation and development and the final phase of political
reactions. Each phase is characterised by the presence of specific #hashtags in
the discussion. Keywords: Twitter, Network analysisComment: 13 pages, 9 figure
Network analysis of a corpus of undeciphered Indus civilization inscriptions indicates syntactic organization
Archaeological excavations in the sites of the Indus Valley civilization
(2500-1900 BCE) in Pakistan and northwestern India have unearthed a large
number of artifacts with inscriptions made up of hundreds of distinct signs. To
date there is no generally accepted decipherment of these sign sequences and
there have been suggestions that the signs could be non-linguistic. Here we
apply complex network analysis techniques to a database of available Indus
inscriptions, with the aim of detecting patterns indicative of syntactic
organization. Our results show the presence of patterns, e.g., recursive
structures in the segmentation trees of the sequences, that suggest the
existence of a grammar underlying these inscriptions.Comment: 17 pages (includes 4 page appendix containing Indus sign list), 14
figure
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