bluuebunny/crossref_metadata_2025_split huggingface dataset:
Computing almost shortest paths
Authors: Elkin Michael 
Published: February 2006

We study the <i>s-sources almost shortest paths</i>
(abbreviated <i>s-ASP</i>) problem. Given an unweighted
graph <i>G</i> &equals; (<i>V,E</i>),
and a subset <i>S</i> &sube; <i>V</i>
of <i>s</i> nodes, the goal is to compute almost
shortest paths between all the pairs of nodes <i>S</i>
&times; <i>V</i>. We devise an algorithm with
running time
<i>O</i>(&mid;<i>E</i>&mid;<i>n</i><sup>&rho;</sup>
&plus; <i>s</i> &middot;
<i>n</i><sup>1 &plus; &zeta;)</sup>
for this problem that computes the paths
<i>P</i><sub><i>u,w</i></sub>
for all pairs (<i>u,w</i>) &isin;
<i>S</i> &times; <i>V</i> such that the
length of
<i>P</i><sub><i>u,w</i></sub>
is at most (1 &plus; &epsi;)
<i>d</i><sub><i>G</i></sub>(<i>u,w</i>)
&plus; &beta;(&zeta;,&rho;,&epsi;), and
&beta;(&zeta;,&rho;,&epsi;) is constant when
&zeta;, &rho;, and &epsi; are arbitrarily small
constants.
We also devise a distributed protocol for the
<i>s</i>-ASP problem that computes the paths
<i>P</i><inf><i>u,w</i></inf>
as above, and has time and communication complexities of
<i>O</i>(<i>s</i> &middot;
<i>Diam(G)</i> &plus;
<i>n</i><sup>1 &plus;
&zeta;/2</sup>) (respectively,
<i>O</i>(<i>s</i> &middot;
<i>Diam(G)</i> log<sup>3</sup>
<i>n</i> &plus; <i>n</i><sup>1
&plus; &zeta;/2</sup> log <i>n</i>)) and
<i>O</i>(&mid;<i>E</i>&mid;
<i>n</i><sup>&rho;</sup> &plus;
<i>s</i> &middot; <i>n</i><sup>1
&plus; &zeta;)</sup> (respectively,
<i>O</i>(&mid;<i>E</i>&mid;
<i>n</i><sup>&rho;</sup> &plus;
<i>s</i> &middot; <i>n</i><sup>1
&plus; &zeta;</sup> &plus;
<i>n</i><sup>1 &plus; &rho; &plus;
&zeta;(&rho; &minus; &zeta;/2)/2)) in the
synchronous (respectively asynchronous) setting.
Our sequential algorithm, as well as the distributed protocol,
is based on a novel algorithm for constructing (1 &plus;
&epsi;, &beta;(&zeta;,&rho;, &epsi;))-spanners
of size <i>O</i>(<i>n</i><sup>1
&plus; &zeta;</sup>), developed in this article. This
algorithm has running time of
<i>O</i>(&mid;<i>E</i>&mid;
<i>n</i><sup>&rho;</sup>), which is
significantly faster than the previously known algorithm given in
Elkin and Peleg [2001], whose running time is
<i>&Otilde;</i>(<i>n</i><sup>2
&plus; &rho;</sup>). We also develop the first
distributed protocol for constructing (1 &plus;
&epsi;,&beta;)-spanners. The communication complexity of
this protocol is near optimal.
The next frontier of users' preferences
Authors: Vitali Fabio 
Published: February 2006

What do you do when you notice a blatant error on a Web page? Write the author? Ignore it? Chalk it up to ignorance? If I feel the error is important---whether or not I think the webmaster is likely to listen to me---I may go looking for an address. But honestly, don't you sometimes wish you could just make the change yourself? In this Whiteboard, Fabio Vitali explores cross-editing and the emerging technology that may make this possible... or seem to be possible...
This will be the last Whiteboard. Although I'll miss it, after six years it's time to do something different.
---Elizabeth Buie
Analysis of Mean Climate Conditions in Senegal (1971–98)
Authors: Fall Souleymane , Niyogi Dev , Semazzi Fredrick H. M. 
Published: February 2006

AbstractThis paper presents a GIS-based analysis of climate variability over Senegal, West Africa. It responds to the need for developing a climate atlas that uses local observations instead of gridded global analyses. Monthly readings of observed rainfall (20 stations) and mean temperature (12 stations) were compiled, digitized, and quality assured for a period from 1971 to 1998. The monthly, seasonal, and annual temperature and precipitation distributions were mapped and analyzed using ArcGIS Spatial Analyst. A north–south gradient in rainfall and an east–west gradient in temperature variations were observed. June exhibits the greatest variability for both quantity of rainfall and number of rainy days, especially in the western and northern parts of the country. Trends in precipitation and temperature were studied using a linear regression analysis and interpolation maps. Air temperature showed a positive and significant warming trend throughout the country, except in the southeast. A significant correlation is found between the temperature index for Senegal and the Pacific sea surface temperatures during the January–April period, especially in the El Niño zone. In contrast to earlier regional-scale studies, precipitation does not show a negative trend and has remained largely unchanged, with a few locations showing a positive trend, particularly in the northeastern and southwestern regions. This study reveals a need for more localized climate analyses of the West Africa region because local climate variations are not always captured by large-scale analysis, and such variations can alter conclusions related to regional climate change.
The Effect of Humidity on the Survival of MRSA on Hard Surfaces
Authors: Makison C. , Swan J. 
Published: February 2006

Methicillin resistant Staphylococcus aureus(MRSA) is an ongoing clinical problem world-wide and a recognised cause of nosocomial infection. In the UK it has been reported that approximately 100,000 patients acquire nosocomial infections per annum, of which 6000 die [1]. If MRSA survives for long periods in health-care environments, this may contribute to infection transmission from fomites. We evaluated the effect of humidity on the survival of MRSA on five different hard surfaces commonly found in health-care establishments. Adjusting the humidity of such environments may provide an inexpensive way of reducing MRSA prevalence. Tiles (1cm2) of five surface types including wood and Formica were inoculated with 5 105–5 106 ATCC EMRSA15 cells suspended in PBS with 1% BSA. EMRSA15 was chosen as it is the most common of two prevalent strains in UK hospitals. Multiple samples of each surface type were then incubated at 42%, 52% and 65% relative humidity (RH) at 23°C (room temperature). Cells from samples of each surface type were re-suspended; agar plates were inoculated and incubated overnight at 37°C and the number of colonies counted. Samples were taken every day for the first week, twice weekly for the following 2 weeks and once a week thereafter. Numbers of viable cells decreased over time from 5105–5106 at day one to below 2 104 by day 22. Minor differences in the rate of decline occurred with different humidities and surface types, generally showing a steep decline in numbers in the first 10 days and a slower decline thereafter. After 57 days numbers were less than 600 but some still persisted.
A Densitometric and Morphometric Analysis of the Skeleton in Adults with Varying Degrees of Growth Hormone Deficiency
Authors: Murray Robert D. , Adams Judith E. , Shalet Stephen M. 
Published: February 2006

Context: Low bone mass is a characteristic feature of the adult GH deficiency (GHD) syndrome, but recent dual-energy x-ray absorptiometry (DXA) studies in patients with GH-receptor and GHRH-receptor gene mutations suggest that the situation is more complex.
Objective: The objective was to define bone areal and volumetric densities and morphometry in hypopituitary adults.
Design: The study was a cross-sectional case-controlled study performed between 1999 and 2001.
Setting: The study was undertaken at an endocrine tertiary referral center.
Patients: Thirty patients with GHD, 24 with GH insufficiency (GHI) [peak GH, 3–7 μg/liter (9–21 mU/liter)], and 30 age- and sex-matched controls were included for study.
Main Outcome Measures: DXA and peripheral quantitative computed tomography (pQCT) derived bone density and morphometry were measured.
Results: No densitometric or morphometric abnormalities were detected in GHD patients who acquired their deficiency during adult life. GHD adults of childhood-onset (CO-GHD) showed decreased bone mineral density at the lumbar spine and hip on DXA. pQCT of the radius showed that CO-GHD patients have normal trabecular bone mineral density and only a 2% decrease in cortical density. Radial bone area was reduced 14.5%, cortical thickness 20%, and cortical cross-sectional area 23%, culminating in a reduction in cortical bone of 25%. The “apparent” low DXA bone density in CO-GHD adults therefore relates primarily to reduced cortical thickness and smaller bone area. DXA and pQCT data derived from adults with GHI revealed no evidence of densitometric or morphometric abnormalities.
Conclusions: 1) Adult-onset GHD patients have normal bone density and size. 2) CO-GHD adults have marginally reduced cortical density but significantly reduced cortical bone as a result of reduced cortical thickness and bone size. 3) GHI has no measurable impact on the skeleton.
Overweight Humans Are Resistant to the Weight-Reducing Effects of Melanocortin4–10
Authors: Hallschmid Manfred , Smolnik Rüdiger , McGregor Gerard , Born Jan , Fehm Horst L. 
Published: February 2006

Context: By enhancing energy expenditure and suppressing appetite, melanocortin peptides derived from proopiomelanocortin play a primary role in the hypothalamic regulation of body weight. In a recent study in normal-weight adults, the 6-wk intranasal administration of the MSH/ACTH4–10 core fragment of proopiomelanocortin resulted in a distinct reduction of body weight and body fat, accompanied by significant decreases in leptin and insulin plasma concentrations.
Objective: The present study aimed to generalize this finding to overweight patients.
Design, Subjects, and Intervention: MSH/ACTH4–10 (0.5 mg) and placebo were intranasally administered once in the morning and once in the evening over a period of 12 wk in 23 overweight men (body mass index, mean ± sem: 29.72 ± 0.43 kg/m2).
Results: MSH/ACTH4–10 did not induce any significant reduction in body weight, body fat, and plasma levels of insulin and leptin as compared with the effects of placebo. Melanocortin treatment was accompanied by reduced cortisol concentrations.
Conclusions: We conclude that contrasting with normal-weight humans, overweight subjects are not susceptible to the effects of melanocortin administration on hypothalamic weight regulatory systems. In overweight subjects, a decreased sensitivity to ACTH/MSH peptides may derive from alterations at the level of the melanocortin receptor or at subsequent steps in the processing of the body fat signal.
The Effects of Growth Hormone and/or Testosterone in Healthy Elderly Men: A Randomized Controlled Trial
Authors: Giannoulis Manthos G. , Sonksen Peter H. , Umpleby Margot , Breen Louise , Pentecost Claire , Whyte Martin , McMillan Carolyn V. , Bradley Clare , Martin Finbarr C. 
Published: February 2006

Context: Declines in GH and testosterone (Te) secretion may contribute to the detrimental aging changes of elderly men.Objective: To assess the effects of near-physiological GH with/without Te administration on lean body mass, total body fat, midthigh muscle cross-section area, muscle strength, aerobic capacity, condition-specific quality of life (Age-Related Hormone Deficiency-Dependent Quality of Life questionnaire), and generic health status (36-Item Short-Form Health Survey) of older men.Design, Settings, and Participants: A 6-month, randomized, double-blind, placebo-controlled trial was performed on 80 healthy, community-dwelling, older men (age, 65–80 yr).Interventions: Participants were randomized to receive 1) placebo GH or placebo Te, 2) recombinant human GH (rhGH) and placebo Te (GH), 3) Te and placebo rhGH (Te), or 4) rhGH and Te (GHTe). GH doses were titrated over 8 wk to produce IGF-I levels in the upper half of the age-specific reference range. A fixed dose of Te (5 mg) was given by transdermal patches.Results: Lean body mass increased with GHTe (P = 0.008) and GH (P = 0.004), compared with placebo. Total body fat decreased with GHTe only (P = 0.02). Midthigh muscle (P = 0.006) and aerobic capacity (P &lt; 0.001) increased only after GHTe. Muscle strength changes were variable; one of six measures significantly increased with GHTe. Significant treatment group by time interactions indicated an improved Age-Related Hormone Deficiency-Dependent Quality of Life questionnaire score (P = 0.007) in the GH and GHTe groups. Bodily pain increased with GH alone, as determined by the Short-Form Health Survey (P = 0.003). There were no major adverse effects.Conclusion: Coadministration of low dose GH with Te resulted in beneficial changes being observed more often than with either GH or Te alone.
Real-Time Prognosis for Metastatic Thyroid Carcinoma Based on 2-[18F]Fluoro-2-Deoxy-d-Glucose-Positron Emission Tomography Scanning
Authors: Robbins Richard J. , Wan Qiang , Grewal Ravinder K. , Reibke Roland , Gonen Mithat , Strauss H. William , Tuttle R. Michael , Drucker William , Larson Steven M. 
Published: February 2006

Context/Objective: Approximately 15% of thyroid cancer patients develop subsequent metastases. The clinical course of patients with metastatic thyroid carcinoma is highly variable. We hypothesized that the metabolic activity of metastatic lesions, as defined by retention of 2-[18F]fluoro-2-deoxyglucose (FDG), would correlate with prognosis.
Design/Patients: The initial FDG-positron emission tomography (PET) scans from 400 thyroid cancer patients were retrospectively reviewed and compared with overall survival (median follow-up, 7.9 yr). We examined the prognostic value of clinical information such as gender, age, serum thyroglobulin, American Joint Committee on Cancer (AJCC) stage, histology, radioiodine avidity, FDG-PET positivity, number of FDG-avid lesions, and the glycolytic rate of the most active lesion.
Results: Age, initial stage, histology, thyroglobulin, radioiodine uptake, and PET outcomes all correlated with survival by univariate analysis. However, only age and PET results continued to be strong predictors of survival under multivariate analysis. The initial American Joint Committee on Cancer stage was not a significant predictor of survival by multivariate analysis. There were significant inverse relationships between survival and both the glycolytic rate of the most active lesion and the number of FDG-avid lesions.
Conclusions: FDG-PET scanning is a simple, expensive, but powerful means to restage thyroid cancer patients who develop subsequent metastases, assigning them to groups that are either at low (FDG negative) or high (FDG positive) risk of cancer-associated mortality. We propose that the aggressiveness of therapy for metastases should match the FDG-PET status.
Dihydrotestosterone Decreases Tumor Necrosis Factor-α and Lipopolysaccharide-Induced Inflammatory Response in Human Endothelial Cells
Authors: Norata Giuseppe Danilo , Tibolla Gianpaolo , Seccomandi Paul Maria , Poletti Angelo , Catapano Alberico Luigi 
Published: February 2006

Context: An increasing body of evidence suggests that testosterone may exert beneficial effects on the development of atherosclerosis. It was suggested that testosterone may act after conversion into estradiol and activation of the estrogen receptors; however, a direct role of androgens on the vascular wall has been proposed.Objective: We investigated the effects of dihydrotestosterone on the proinflammatory response observed in human endothelial cells.Design: Human endothelial cells isolated from umbilical cords were incubated with lipopolysaccharide or TNFα in the presence or absence of dihydrotestosterone (DHT). mRNA and cellular proteins were processed for gene expression studies, and transient transfection experiments were performed to investigate molecular mechanisms involved in the effects observed.Setting: These studies took place at the Department of Pharmacological Sciences, University of Milan, Milan, Italy.Results: Lipopolysaccharide and TNFα induced VCAM-1 and ICAM-1 mRNA and protein expression, as detected by real-time quantitative PCR, fluorescence-activated cell sorting, and confocal microscopy, but this effect was inhibited when cells were incubated with DHT. In addition, DHT inhibited mRNA expression of IL-6, MCP-1, CD40, TLR4, PAI-1, and Cox-2 and the release of cytokines and chemokines such as GRO, granulocyte-macrophage colony-stimulating factor, and TNF. The DHT effect was counteracted by bicalutamide, an antagonist of the androgen receptor. Furthermore, when cells were cotransfected with a Cox-2 promoter or a 3X-NF-κB luciferase reporter vector and a plasmid expressing the human androgen receptor, DHT treatment inhibited the increase of the luciferase activity observed with TNFα.Conclusion: DHT could positively regulate endothelial function through the control of the inflammatory response mediated by nuclear factor-κB in endothelial cells.
Adolescent Girls with Polycystic Ovary Syndrome Have an Increased Risk of the Metabolic Syndrome Associated with Increasing Androgen Levels Independent of Obesity and Insulin Resistance
Authors: Coviello Andrea D. , Legro Richard S. , Dunaif Andrea 
Published: February 2006

Context: Adult women with polycystic ovary syndrome (PCOS) have an increased prevalence of the metabolic syndrome (MBS). The prevalence of MBS is also increasing in adolescents.
Objective: Our objective was to test the hypothesis that the prevalence of MBS is increased in adolescent girls with PCOS compared with the general population and to determine the factors associated with an increased risk of the MBS in PCOS.
Design and Setting: We conducted a cross-sectional case-control study at academic medical centers with general clinical research centers.
Participants: Participants included 49 adolescent girls with PCOS and 165 girls from the Third National Health and Nutrition Examination Survey (NHANES III) adolescent population of similar age and ethnic background.
Main Outcome Measure: We assessed the prevalence of MBS according to currently proposed adolescent MBS criteria.
Results: Thirty-seven percent of adolescent girls with PCOS had MBS compared with 5% of NHANES III girls (P &lt; 0.0001). None of the girls of normal body mass index (BMI) had MBS, whereas 11% of overweight and 63% of obese girls with PCOS had MBS compared with 0 and 32% of NHANES III girls, respectively. Girls with PCOS were 4.5 times more likely to have MBS than age-matched NHANES III girls after adjusting for BMI (odds ratio, 4.5; 95% confidence interval, 1.1–17.7; P = 0.03). The odds of having the MBS were 3.8 times higher for every quartile increase in bioavailable testosterone in girls with PCOS after adjusting for BMI and insulin resistance (odds ratio, 3.8; 95% confidence interval, 1.4–10.2; P = 0.008).
Conclusions: Adolescent girls with PCOS have a higher prevalence of MBS than the general adolescent population. Hyperandrogenemia is a risk factor for MBS independent of obesity and insulin resistance.
Somatic and Germline Mosaicism for a Mutation of the PHEX Gene Can Lead to Genetic Transmission of X-Linked Hypophosphatemic Rickets That Mimics an Autosomal Dominant Trait
Authors: Goji Katsumi , Ozaki Kayo , Sadewa Ahmad H. , Nishio Hisahide , Matsuo Masafumi 
Published: February 2006

Context: Familial hypophosphatemic rickets is usually transmitted as an X-linked dominant disorder (XLH), although autosomal dominant forms have also been observed. Genetic studies of these disorders have identified mutations in PHEX and FGF23 as the causes of X-linked dominant disorder and autosomal dominant forms, respectively.
Objective: The objective of the study was to describe the molecular genetic findings in a family affected by hypophosphatemic rickets with presumed autosomal dominant inheritance.
Patients: We studied a family in which the father and the elder of his two daughters, but not the second daughter, were affected by hypophosphatemic rickets. The pedigree interpretation of the family suggested that genetic transmission of the disorder occurred as an autosomal dominant trait.
Methods and Results: Direct nucleotide sequencing of FGF23 and PHEX revealed that the elder daughter was heterozygous for an R567X mutation in PHEX, rather than FGF23, suggesting that the genetic transmission occurred as an X-linked dominant trait. Unexpectedly, the father was heterozygous for this mutation. Single-nucleotide primer extension and denaturing HPLC analysis of the father using DNA from single hair roots revealed that he was a somatic mosaic for the mutation. Haplotype analysis confirmed that the father transmitted the genotypes for 18 markers on the X chromosome equally to his two daughters. The fact that the father transmitted the mutation to only one of his two daughters indicated that he was a germline mosaic for the mutation.
Conclusions: Somatic and germline mosaicism for an X-linked dominant mutation in PHEX may mimic autosomal dominant inheritance.
Limitation of the Homeostasis Model Assessment to Predict Insulin Resistance and β-Cell Dysfunction in Older People
Authors: Chang Annette M. , Smith Marla J. , Bloem Cathie J. , Galecki Andrzej T. , Halter Jeffrey B. , Supiano Mark A. 
Published: February 2006

Context: Studies in older people have shown inconsistent agreement between homeostasis model assessment of insulin resistance (HOMA-IR) and dynamic measures of insulin action and have not evaluated HOMA β-cell.
Objective: We compared measures of insulin sensitivity and β-cell function from the frequently sampled iv glucose tolerance test (FSIGT) to HOMA models.
Design/Patients/Setting/Intervention: Two hundred fourteen young and old with normal glucose tolerance (NGT) and old with impaired glucose tolerance (IGT) participated in a retrospective analysis of FSIGT data in a university medical setting.
Main Outcome Measure: Sensitivity to insulin (SI) and acute insulin response to glucose (AIRg) from FSIGT were compared with HOMA models.
Results: SI and HOMA-IR measures identified similar patterns of increasing insulin resistance in the two older groups, compared with younger people with NGT, with the greatest degree of insulin resistance in older people with IGT (P &lt; 0.05 vs. young and old NGT for both SI and HOMA-IR). Agreement between HOMA-IR and SI was moderate (weighted kappa = 0.51). AIRg was similar in young and old NGT but was markedly decreased in old IGT (P &lt; 0.05 vs. young and old NGT). HOMA-β-cell was similar in the three groups. Agreement between HOMA β-cell and AIRg was weak (weighted kappa = 0.35).
Conclusions: HOMA-IR may detect age-related insulin resistance when comparing large populations of older people. However, dynamic testing appears to be necessary to quantitate diminished insulin secretion in older people.