bluuebunny/crossref_metadata_2025 huggingface dataset:
Contribution of Fast and Slow Conducting Myelinated Axons to Single-Peak Compound Action Potentials in Rat Spinal Cord White Matter Preparations
Authors: Velumian Alexander A. , Wan Yudi , Samoilova Marina , Fehlings Michael G.
Published: December 2010

Unlike recordings derived from optic nerve or corpus callosum, compound action potentials (CAPs) recorded from rodent spinal cord white matter (WM) have a characteristic single-peak shape despite the heterogeneity of axonal populations. Using a double sucrose gap technique, we analyzed the CAPs recorded from dorsal, lateral, and ventral WM from mature rat spinal cord. The CAP decay was significantly prolonged with increasing stimulus intensities suggesting a recruitment of higher threshold, slower conducting axons. At 3.5 mm conduction distance, a hidden higher threshold, slower conducting component responsible for prolongation of CAP decay was uncovered in 22 of 25 of dorsal WM strips by analyzing the stimulus-response relationships and a normalization-subtraction procedure. This component had a peak conduction velocity (CV) of 5.0 ± 0.2 (SE) m/s as compared with 9.3 ± 0.5 m/s for the lower threshold peak ( P < 0.0001). Oxygen-glucose deprivation (OGD), along with its known effects on CAP amplitude, significantly ( P < 0.015) shortened the CAP decay. The hidden higher threshold, slower conducting component showed greater sensitivity to OGD compared with the lower threshold, faster conducting component, suggesting a differential sensitivity of axonal populations of spinal cord WM. At longer conduction distances and lower temperatures (9.8 mm, 22–24°C), the slower peak could be directly visualized in CAPs at higher stimulation intensities. A detailed analysis of single-peak CAPs to identify their fast and slow conducting components may be of particular importance for studies of axonal physiology and pathophysiology in small animals where the conduction distance is not sufficiently long to separate the CAP peaks.
Dynamics of Within-, Inter-, and Cross-Modal Attentional Modulation
Authors: Kida Tetsuo , Inui Koji , Tanaka Emi , Kakigi Ryusuke
Published: December 2010

Numerous studies have demonstrated effects of spatial attention within single sensory modalities (within-modal spatial attention) and the effect of directing attention to one sense compared with the other senses (intermodal attention) on cortical neuronal activity. Furthermore, recent studies have been revealing that the effects of spatial attention directed to a certain location in a certain sense spread to the other senses at the same location in space (cross-modal spatial attention). The present study used magnetoencephalography to examine the temporal dynamics of the effects of within-modal and cross-modal spatial and intermodal attention on cortical processes responsive to visual stimuli. Visual or tactile stimuli were randomly presented on the left or right side at a random interstimulus interval and subjects directed attention to the left or right when vision or touch was a task-relevant modality. Sensor-space analysis showed that a response around the occipitotemporal region at around 150 ms after visual stimulation was significantly enhanced by within-modal, cross-modal spatial, and intermodal attention. A later response over the right frontal region at around 200 ms was enhanced by within-modal spatial and intermodal attention, but not by cross-modal spatial attention. These effects were estimated to originate from the occipitotemporal and lateral frontal areas, respectively. Thus the results suggest different spatiotemporal dynamics of neural representations of cross-modal attention and intermodal or within-modal attention.
Iterative Schemes for Fixed Points of Relatively Nonexpansive Mappings and Their Applications
Authors: Plubtieng Somyot , Sriprad Wanna
Published: December 2010

We present two iterative schemes with errors which are proved to be strongly convergent
to a common element of the set of fixed points of a countable family of relatively nonexpansive mappings
and the set of fixed points of nonexpansive mappings in the sense of Lyapunov functional in a real uniformly
smooth and uniformly convex Banach space. Using the result we consider strong convergence theorems for
variational inequalities and equilibrium problems in a real Hilbert space and strong convergence theorems
for maximal monotone operators in a real uniformly smooth and uniformly convex Banach space.
Taxonomic Review of theCaudatella heterocaudata(McDunnough) andC. hystrix(Traver) Complexes (Insecta: Ephemeroptera: Ephemerellidae)
Authors: Jacobus Luke M.
Published: December 2010

Caudatella columbiella(McDunnough, 1935), new combination, (Insecta: Ephemeroptera: Ephemerellidae) is removed from synonymy withCaudatella heterocaudata(McDunnough, 1929), and a new junior synonym is recognized, based on comparative examination of type material and larval exuviae associated with adults from the type locale ofC. columbiella(=C. californica(Allen and Edmunds, 1961), new status, new synonym).Caudatella circia(Allen and Edmunds, 1961), new status, is recognized as a strict specific synonym ofC. heterocaudata(McDunnough, 1929) (=C. circia(Allen and Edmunds, 1961), new synonym). A neotype is designated forCaudatella hystrix(Traver, 1934), based on a specimen collected in Western Montana, USA, during June 2000. Morphological differences between the type specimen ofC. hystrixand the type specimens of its two junior synonyms,Ephemerella cascadiaAllen and Edmunds, 1961, andE. spinosaMayo, 1952, are detailed. An identification key for larvae of the genusCaudatellais included.
A Gentleman with Anemia and Cholestasis
Authors: Law Siu-Tong , Lee Wai-Ki , Li Michael Kin-Kong , Lok Ka-Ho
Published: December 2010

Primary sclerosing cholangitis is a rare cause of cholestasis caused by progressive inflammation and fibrosis of both intrahepatic and extrahepatic bile ducts leading to multifocal ductal strictures. Herein, we report a case of primary sclerosing cholangitis and inflammatory bowel disease. The concomitant diagnosis of these two diseases is not typical. The management includes the treatment of inflammatory bowel disease and potential complications of primary sclerosing cholangitis, including dominant strictures of bile duct, portal hypertension, gallbladder diseases, cholangiocarcinoma, and colonoscopic surveillance.
A New Approach for the Solution of Three‐Dimensional Magnetohydrodynamic Rotating Flow over a Shrinking Sheet
Authors: Motsa S. S. , Shateyi S.
Published: December 2010

The numerical solution of magnetohydrodynamic (MHD) and rotating flow over a porous shrinking sheet is obtained by the new approach known as spectral homotopy analysis method (SHAM). Using a similarity transformation, the governing equations for the momentum are reduced to a set of ordinary differential equations and are solved by the SHAM approach to determine velocity distributions and shear stress variations for different governing parameters. The SHAM results are analysed and validated against numerical results obtained using MATLAB′s built‐in bvp4c routine, and good agreement is observed.
Interactions of Overweight, Poor Oral Health, and Stress Related to Chronic Disease in an Aging Population
Authors: Albright Julia W.
Published: December 2010

The prevalence of excess body mass (XBM), poor oral health (POH), and stress in a secluded population of aged (≥60 years) Hmong immigrants was surveyed. The findings were related to the prevalence of diabetes in the same population. Diabetes was associated separately with POH (OR 2.4; CL 1.3, 4.2) or with XBM (OR 2.5; CL 1.4, 4.8). The association of diabetes with the combination of XBM and POH was striking (OR 5.1; CL 3.4, 7.5); that apparent synergism has not been fully appreciated. We describe a mechanism that explains the synergism. The concept of “thrifty genotype” is a plausible explanation of XBM in the elderly Hmong immigrants and possibly the current older Laotian population. POH is common among elderly Laotians as it is in most developing countries. We conclude that synergism of XBM and POH significantly elevates the prevalence of diabetes among aging populations and probably other age groups as well.
No Weight Catch-Up Growth of SGA Infants Is Associated with Impaired Insulin Sensitivity during the Early Postnatal Period
Authors: Han Tong-yan , Wang Xin-li , Cui Yun-pu , Ye Hong-mao , Tong Xiao-mei , Piao Mei-hua
Published: December 2010

Objective. To investigate the relationship between weight catch-up growth and insulin sensitivity in small for gestational age (SGA) infants.Methods. Forty-four singleton SGA subjects met the inclusion criteria and finished-3-month followup. Body weight, length, fasting glucose, and fasting insulin (FI) levels were measured at 3 days and 3 months. Insulin sensitivity was evaluated by FI and homeostasis model assessment (HOMA).Results. According to the change of weight Z-score, forty-four subjects were divided into two groups: noncatch-up growth (NCUG) and catch-up growth (CUG). By 3 months of age, the body weight, body length and BMI of NCUG group were significantly lower than those of CUG group. The FI and HOMA were significantly higher in NCUG group. The change of weight Z-score during 3 months was inversely related to the HOMA at 3 months.Conclusion. Our data exemplified that no weight catch-up growth during the first 3 months was associated with impaired insulin sensitivity in SGA infants.
Generation and Analysis of Expressed Sequence Tags fromOlea europaeaL.
Authors: Ozdemir Ozgenturk Nehir , Oruç Fatma , Sezerman Ugur , Kuçukural Alper , Vural Korkut Senay , Toksoz Feriha , Un Cemal
Published: December 2010

Olive (Olea europaeaL.) is an important source of edible oil which was originated in Near-East region. In this study, two cDNA libraries were constructed from young olive leaves and immature olive fruits for generation of ESTs to discover the novel genes and search the function of unknown genes of olive. The randomly selected 3840 colonies were sequenced for EST collection from both libraries. Readable 2228 sequences for olive leaf and 1506 sequences for olive fruit were assembled into 205 and 69 contigs, respectively, whereas 2478 were singletons. Putative functions of all 2752 differentially expressed unique sequences were designated by gene homology based on BLAST and annotated using BLAST2GO. While 1339 ESTs show no homology to the database, 2024 ESTs have homology (under 80%) with hypothetical proteins, putative proteins, expressed proteins, and unknown proteins in NCBI-GenBank. 635 EST's unique genes sequence have been identified by over 80% homology to known function in other species which were not previously described in Olea family. Only 3.1% of total EST's was shown similarity with olive database existing in NCBI. This generated EST's data and consensus sequences were submitted to NCBI as valuable source for functional genome studies of olive.
On Properties of Solutions for Two Functional Equations Arising in Dynamic Programming
Authors: Liu Zeqing , Ume JeongSheok , Kang ShinMin
Published: December 2010

We introduce and study two new functional equations, which contain a lot of known functional equations as special cases, arising in dynamic programming of multistage decision processes. By applying a new fixed point theorem, we obtain the existence, uniqueness, iterative approximation, and error estimate of solutions for these functional equations. Under certain conditions, we also study properties of solutions for one of the functional equations. The results presented in this paper extend, improve, and unify the results according to Bellman, Bellman and Roosta, Bhakta and Choudhury, Bhakta and Mitra, Liu, Liu and Ume, and others. Two examples are given to demonstrate the advantage of our results over existing results in the literature.
Modelling and Analysis of a Pest‐Control Pollution Model with Integrated Control Tactics
Authors: Chen Yiping , Liu Zhijun , Qin Wenjie
Published: December 2010

A hybrid impulsive pest control model with stage structure for pest and Holling
II functional response is proposed and investigated, in which the effects of impulsive pesticide
input in the environment and in the organism are considered. Sufficient conditions for global
attractiveness of the pest‐extinction periodic solution and permanence of the system are obtained,
which show that there exists a globally asymptotically stable pest‐extinction periodic
solution when the number of natural enemies released is more than some critical value, whereas
the system can be permanent when the number of natural enemies released is less than another
critical value. Furthermore, numerical simulations are carried out to illustrate our theoretical
results and facilitate their interpretation.
Two‐Phase Generalized Reduced Gradient Method for Constrained Global Optimization
Authors: El Mouatasim Abdelkrim
Published: December 2010

The random perturbation of generalized reduced gradient method for optimization under nonlinear differentiable constraints is proposed. Generally speaking, a particular iteration of this method proceeds in two phases. In the Restoration Phase, feasibility is restored by means of the resolution of an auxiliary nonlinear problem, a generally nonlinear system of equations. In the Optimization Phase, optimality is improved by means of the consideration of the objective function, on the tangent subspace to the constraints. In this paper, optimal assumptions are stated on the Restoration Phase and the Optimization Phase that establish the global convergence of the algorithm. Some numerical examples are also given by mixture problem and octagon problem.
A Molecular Mechanics Study of Morphologic Interaction between Graphene and Si Nanowires on a SiO2Substrate
Authors: Zhang Zhao , Li Teng
Published: December 2010

We study the morphologic interaction between graphene and Si nanowires on a SiO2substrate, using molecular mechanics simulations. Two cases are considered: (1) a graphene nanoribbon intercalated by a single Si nanowire on a SiO2substrate and (2) a blanket graphene flake intercalated by an array of Si nanowires evenly patterned in parallel on a SiO2substrate. Various graphene morphologies emerge from the simulation results of these two cases, which are shown to depend on both geometric parameters (e.g., graphene nanoribbon width, nanowire diameter, and nanowire spacing) and material properties (e.g., graphene-nanowire and graphene-substrate bonding strength). While the quantitative results at the atomistic resolution in this study can be further used to determine the change of electronic properties of graphene under morphologic regulation, the qualitative understandings from this study can be extended to help exploring graphene morphology in other material systems.
Clustering ofMycobacterium tuberculosisCases in Acapulco: Spoligotyping and Risk Factors
Authors: Nava-Aguilera Elizabeth , López-Vidal Yolanda , Harris Eva , Morales-Pérez Arcadio , Mitchell Steven , Flores-Moreno Miguel , Villegas-Arrizón Ascencio , Legorreta-Soberanis José , Ledogar Robert , Andersson Neil
Published: December 2010

Recurrence and reinfection of tuberculosis have quite different implications for prevention. We identified 267 spoligotypes ofMycobacterium tuberculosisfrom consecutive tuberculosis patients in Acapulco, Mexico, to assess the level of clustering and risk factors for clustered strains. Point cluster analysis examined spatial clustering. Risk analysis relied on the Mantel Haenszel procedure to examine bivariate associations, then to develop risk profiles of combinations of risk factors. Supplementary analysis of the spoligotyping data used SpolTools. Spoligotyping identified 85 types, 50 of them previously unreported. The five most common spoligotypes accounted for 55% of tuberculosis cases. One cluster of 70 patients (26% of the series) produced a single spoligotype from the Manila Family (Clade EAI2). The high proportion (78%) of patients infected with cluster strains is compatible with recent transmission of TB in Acapulco. Geomatic analysis showed no spatial clustering; clustering was associated with a risk profile of uneducated cases who lived in single-room dwellings. The Manila emerging strain accounted for one in every four cases, confirming that one strain can predominate in a hyperendemic area.
Quantitative Cartilage Imaging in Knee Osteoarthritis
Authors: Eckstein Felix , Wirth Wolfgang
Published: December 2010

Quantitative measures of cartilage morphology (i.e., thickness) represent potentially powerful surrogate endpoints in osteoarthritis (OA). These can be used to identify risk factors of structural disease progression and can facilitate the clinical efficacy testing of structure modifying drugs in OA. This paper focuses on quantitative imaging of articular cartilage morphology in the knee, and will specifically deal with different cartilage morphology outcome variables and regions of interest, the relative performance and relationship between cartilage morphology measures, reference values for MRI-based knee cartilage morphometry, imaging protocols for measurement of cartilage morphology (including those used in the Osteoarthritis Initiative), sensitivity to change observed in knee OA, spatial patterns of cartilage loss as derived by subregional analysis, comparison of MRI changes with radiographic changes, risk factors of MRI-based cartilage loss in knee OA, the correlation of MRI-based cartilage loss with clinical outcomes, treatment response in knee OA, and future directions of the field.
Antiretroviral Treatment-Associated Tuberculosis in a Prospective Cohort of HIV-Infected Patients Starting ART
Authors: Worodria William , Massinga-Loembe Marguerite , Mayanja-Kizza Harriet , Namaganda Jane , Kambugu Andrew , Manabe Yukari C. , Kestens Luc , Colebunders Robert
Published: December 2010

Commencement of antiretroviral treatment (ART) in severely immunosuppressed HIV-infected persons is associated with unmasking of subclinical disease. The subset of patients that are diagnosed with tuberculosis (TB) disease while on ART have been classified as ART-associated TB. Few studies have reported the incidence of ART-associated TB and unmasking TB-IRIS according to the International Network for the Study of HIV-Associated IRIS (INSHI) consensus definition. To determine the incidence and predictors of ART-associated TB, we screened 219 patients commencing ART at the Infectious Diseases Clinic in Kampala, Uganda for TB by symptoms, sputum microscopy, and chest X-rays and followed them for one year. Fourteen (6.4%) patients were diagnosed with TB during followup. Eight (3.8%) patients had ART-associated TB (incidence rate of 4.3 per 100 person years); of these, three patients fulfilled INSHI criteria for unmasking TB-associated IRIS (incidence rate of 1.6 per 100 person years). A body mass index of less than 18.5 kg/m2BMI (HR 5.85 95% CI 1.24–27.46,P=.025) and a C-reactive protein greater than 5 mg/L (HR 8.23 95% CI 1.36–38.33,P=.020) were risk factors for ART-associated TB at multivariate analysis. In conclusion, with systematic TB screening (including culture and chest X-ray), the incidence of ART-associated TB is relatively low in settings with high HIV and TB prevalence.
Dark Matter: A Primer
Authors: Garrett Katherine , Duda Gintaras
Published: December 2010

Dark matter is one of the greatest unsolved mysteries in cosmology at the present time. About 80% of the Universe's gravitating matter is nonluminous, and its nature and distribution are for the most part unknown. In this paper, we will outline the history, astrophysical evidence, candidates, and detection methods of dark matter, with the goal to give the reader an accessible but rigorous introduction to the puzzle of dark matter. This paper targets advanced students and researchers new to the field of dark matter, and includes an extensive list of references for further study.
Immunobiomarkers in Small Cell Lung Cancer: Potential Early Cancer Signals
Authors: Chapman Caroline J. , Thorpe Alison J. , Murray Andrea , Parsy-Kowalska Celine B. , Allen Jared , Stafford Kelly M. , Chauhan Alok S. , Kite Thomas A. , Maddison Paul , Robertson John F. R.
Published: December 2010

Purpose: We investigated the presence of autoantibodies as immunobiomarkers to a panel of tumor-associated antigens in a group of individuals with small cell lung cancer (SCLC), a disease group that has a poor overall cancer prognosis and therefore may benefit most from early diagnosis.

Experimental Design: Sera from 243 patients with confirmed SCLC and normal controls matched for age, sex, and smoking history were analyzed for the presence of these early immunobiomarkers (i.e., autoantibodies to p53, CAGE, NY-ESO-1, GBU4-5, Annexin I, SOX2, and Hu-D) by ELISA.

Results: Autoantibodies were seen to at least 1 of 6 antigens in 55% of all the SCLC patients' sera tested, with a specificity of 90% compared with controls. Using a higher assay cutoff to achieve a specificity of 99%, autoantibodies were still detectable in 42% of SCLC patients (receiver operator characteristic area under the curve = 0.76). There was no significant difference in sensitivity when analyzed by stage of the cancer or by patient age or gender. The frequency of autoantibodies to individual antigens varied, ranging from 4% for GBU4-5 to 35% for SOX2. Levels of Annexin I autoantibodies were not elevated in patients with SCLC. Antibodies were also detected in 4 separate patients whose sera were taken up to 3 months before tumor diagnosis.

Conclusion: The presence of an autoantibody to one or more cancer-associated antigens may provide an important addition to the armamentarium available to the clinician to aid early detection of SCLC in high-risk individuals. Clin Cancer Res; 17(6); 1474–80. ©2011 AACR.
Physician and Patient Influences on Provider Performance
Authors: Funkhouser Ellen , Houston Thomas K. , Levine Deborah A. , Richman Joshua , Allison Jeroan J. , Kiefe Catarina I.
Published: December 2010

Background—

Efforts to improve the quality of care for patients with cardiovascular disease frequently target the decrease of physician-level performance variability. We assessed how variability in providing β-blockers to ambulatory postmyocardial infarction (MI) patients was influenced by physician and patient level characteristics.

Methods and Results—

β-Blocker prescription and patient characteristics were abstracted from charts of post-MI patients treated by 133 primary care physicians between 2003 and 2007 and linked to physician and practice characteristics. Associations of β-blocker prescription with physician- and patient-level characteristics were examined using mixed-effects models, with physician-level effects as random. Mean physician-specific predicted probabilities and the intraclass correlations, which assessed the proportion of variance explainable at the physician level, were estimated. Of 1901 patients without major contraindication, 69.1% (range across physicians, 20% to 100%) were prescribed β-blockers. Prescription varied with comorbidity from 78.3% in patients with chronic kidney disease to 54.7% for patients with stroke. Although physician characteristics such as older physician age, group practice, and rural location were each positively associated with β-blocker prescription, physician factors accounted for only 5% to 8% of the variance in β-blocker prescription; the preponderance of the variance, 92% to 95%, was at the patient level. The mean physician-specific probability of β-blocker prescription (95% confidence interval) in the fully adjusted model was 63% (61% to 65%).

Conclusions—

β-Blocker prescription rates were surprisingly low. The contribution of physician factors to overall variability in β-blocker prescription, however, was limited. Increasing evidence-based use of β-blockers may not be accomplished by focusing mostly on differential performance across physicians.
Lifetime Costs of Medical Care After Heart Failure Diagnosis
Authors: Dunlay Shannon M. , Shah Nilay D. , Shi Qian , Morlan Bruce , VanHouten Holly , Hall Long Kirsten , Roger Véronique L.
Published: December 2010

Background—

Heart failure (HF) care constitutes an increasing economic burden on the health care system, and has become a key focus in the health care debate. However, there are limited data on the lifetime health care costs for individuals with HF after initial diagnosis.

Methods and Results—

Olmsted County residents with incident HF from 1987 to 2006 were identified. Direct medical costs incurred from the time of HF diagnosis until death or last follow-up were obtained using population-based administrative data through 2007. Costs were inflated to 2008 US dollars using the general Consumer Price Index. Inpatient, outpatient, and total costs were estimated using a 2-part model with adjustment for right censoring of data. Predictors of total costs were examined using a similar model. A total of 1054 incident HF patients were identified (mean age, 76.8 years; 46.1% men). After a mean follow-up of 4.6 years, 765 (72.6%) patients had died. The estimated total lifetime costs were $109 541 (95% confidence interval, $100 335 to 118 946) per person, with the majority accumulated during hospitalizations (mean, $83 980 per person). After adjustment for age, year of diagnosis, and comorbidity, diabetes mellitus and preserved ejection fraction (≥50%) were associated with 24.8% (
P
=0.003) and 23.6% (
P
=0.041) higher lifetime costs, respectively. Higher costs were observed at initial HF diagnosis and in the months immediately before death in those surviving >12 months after diagnosis.

Conclusions—

HF imposes a significant economic burden, primarily related to hospitalizations. Variations in cost over a lifetime can help identify strategies for efficient management of patients, particularly at the end of life.
Cost-Effectiveness of Genetic Testing in Family Members of Patients With Long-QT Syndrome
Authors: Perez Marco V. , Kumarasamy Narmadan A. , Owens Douglas K. , Wang Paul J. , Hlatky Mark A.
Published: December 2010

Background—

Family members of patients with established long-QT syndrome (LQTS) often lack definitive clinical findings, yet may have inherited an LQTS mutation and be at risk of sudden death. Genetic testing can identify mutations in 75% of patients with LQTS, but genetic testing of family members remains controversial.

Methods and Results—

We used a Markov model to assess the cost-effectiveness of 3 strategies for treating an asymptomatic 10-year-old, first-degree relative of a patient with clinically evident LQTS. In the genetic testing strategy, relatives undergo genetic testing only for the mutation identified in the index patient, and relatives who test positive for the mutation are treated with β-blockers. This strategy was compared with (1) empirical treatment of relatives with β-blockers and (2) watchful waiting, with treatment only after development of symptoms. The genetic testing strategy resulted in better survival and quality-adjusted life years at higher cost, with a cost-effectiveness ratio of $67 400 per quality-adjusted life year gained compared with watchful waiting. The cost-effectiveness of the genetic testing strategy improved to less than $50 000 per quality-adjusted life year gained when applied selectively either to (1) relatives with higher clinical suspicion of LQTS (pretest probability 65% to 81%), or to (2) families with a higher than average risk of sudden death, or to (3) larger families (2 or more first-degree relatives tested).

Conclusions—

Genetic testing of young first-degree relatives of patients with definite LQTS is moderately expensive, but can reach acceptable thresholds of cost-effectiveness when applied to selected patients.
Regional Variation in the Use of Implantable Cardioverter-Defibrillators for Primary Prevention
Authors: Matlock Dan D. , Peterson Pamela N. , Heidenreich Paul A. , Lucas F. Lee , Malenka David J. , Wang Yongfei , Curtis Jeptha P. , Kutner Jean S. , Fisher Elliott S. , Masoudi Frederick A.
Published: December 2010

Background—

Although the use of implantable cardioverter-defibrillators (ICDs) for the primary prevention of sudden cardiac death varies by sex, race, and hospital, geographic variation in ICD use remains unexplored. Our objective was to quantify regional variations in the utilization of primary prevention ICDs in the United States, and to evaluate if an association exists between utilization and physician supply or the proportion of patients meeting the trial inclusion criteria.

Methods and Results—

This is a cross-sectional analysis among the Medicare, fee-for-service population from the National Cardiovascular Data Registry. Using hospital referral regions, we calculated the age-, sex-, and race-adjusted rates of ICD placement for each region and assessed the correlation between these rates and (1) physician supply and (2) the proportion of patients meeting trial inclusion criteria. Substantial variation was found across quintiles of rate ratios of ICD implantation, ranging from 0.39 to 1.77 (compared with a national mean rate of 1.0). This ratio was not correlated with the supply of cardiologists (
R
2
=0.01), electrophysiologists (
R
2
=0.01), or with the proportion of patients meeting trial inclusion criteria (
R
2
<0.01). Over all, 13% of all patients receiving ICDs did not meet trial criteria.

Conclusions—

Marked geographic variation in the use of primary prevention ICDs exists across the United States that is not correlated with physician supply. Although >1 in 10 patients received ICDs outside of trial criteria, this potential overuse did not explain the variation. Future studies should consider underuse or misuse of primary prevention ICDs as causes of geographic variation.
Predictability of Seasonal Sahel Rainfall Using GCMs and Lead-Time Improvements Through the Use of a Coupled Model
Authors: Ndiaye Ousmane , Ward M. Neil , Thiaw Wassila M.
Published: December 2010

The ability of several atmosphere-only and coupled ocean–atmosphere general circulation models (AGCMs and CGCMs, respectively) is explored for the prediction of seasonal July–September (JAS) Sahel rainfall. The AGCMs driven with observed sea surface temperature (SST) over the period 1968–2001 confirm the poor ability of such models to represent interannual Sahel rainfall variability. However, using a model output statistics (MOS) approach with the predicted low-level wind field over the tropical Atlantic and western part of West Africa yields good Sahel rainfall skill for all models. Skill is mostly captured in the leading empirical orthogonal function (EOF1), representing large-scale fluctuation in the regional circulation system over the tropical Atlantic. This finding has operational significance for the utility of AGCMs for short lead-time prediction based on persistence of June SST information; however, studies have shown that for longer lead-time forecasts, there is substantial loss of skill, relative to that achieved using the observed JAS SST.

The potential of CGCMs is therefore explored for extending the lead time of Sahel rainfall predictions. Some of the models studied, when initialized using April information, show potential to at least match the levels of skill achievable from assuming persistence of April SST. One model [NCEP Climate Forecasting System (CFS)] was found to be particularly promising. Diagnosis of the hindcasts available for the CFS (from lead times up to six months for 1981–2008) suggests that, especially by applying the same MOS approach, skill is achieved through capturing interannual variations in Sahel rainfall (primarily related to El Niño–Southern Oscillation in the period of study), as well as the upward trend in Sahel rainfall that is observed over 1981–2008, which has been accompanied by a relative warming in the North Atlantic compared to the South Atlantic. At lead times up to six months (initialized forecasts in December), skill levels are maintained with the correlation between predicted and observed Sahel rainfall at approximately r = 0.6. While such skill levels at these long lead times are notably higher than previously achieved, further experiments, such as over the same period and with comparable AGCMs, are required for definitive attribution of the advance to the use of a coupled ocean–atmosphere modeling approach. Nonetheless, the detrended skill achieved here by the January–March initializations (r = 0.33) must require an approach that captures the evolution of the key ocean–atmosphere anomalies from boreal winter to boreal summer, and approaches that draw on persistence in ocean conditions have not previously been successful.
Evolution of the Arctic Ocean Salinity, 2007–08: Contrast between the Canadian and the Eurasian Basins
Authors: Lique Camille , Garric Gilles , Treguier Anne-Marie , Barnier Bernard , Ferry Nicolas , Testut Charles-Emmanuel , Girard-Ardhuin Fanny
Published: December 2010

The authors investigate the variability of salinity in the Arctic Ocean and in the Nordic and Labrador Seas over recent years to see how the freshwater balance in the Arctic and the exchanges with the North Atlantic have been affected by the recent important sea ice melting, especially during the 2007 sea ice extent minimum. The Global Ocean Reanalysis and Simulations (GLORYS1) global ocean reanalysis based on a global coupled ocean–sea ice model with an average of 12-km grid resolution in the Arctic Ocean is used in this regard. Although no sea ice data and no data under sea ice are assimilated, simulation over the 2001–09 period is shown to represent fairly well the 2007 sea ice event and the different components accounting for the ocean and sea ice freshwater budget, compared to available observations. In the reanalysis, the 2007 sea ice minimum is due to an increase of the sea ice export through Fram Strait (25%) and an important sea ice melt in the Arctic (75%). Liquid freshwater is accumulated in the Beaufort gyre after 2002, in agreement with recent observations, and it is shown that this accumulation is due to both the sea ice melt and a spatial redistribution of the freshwater content in the Canadian Basin. In the Eurasian Basin, a very contrasting situation is found with an increase of the salinity. The effect of the sea ice melt is counterbalanced by an increase of the Atlantic inflow and a modification of the circulation north of Fram Strait after 2007. The authors suggest that a strong anomaly of the atmospheric conditions was responsible for this change of the circulation.
Influence of Langmuir Circulation on the Deepening of the Wind-Mixed Layer
Authors: Noh Yign , Goh Gahyun , Raasch Siegfried
Published: December 2010

Analysis of large eddy simulation data reveals that Langmuir circulation (LC) induces a significant enhancement of the mixed layer deepening, only if the mixed layer depth (MLD) h is shallow and the buoyancy jump across it ΔB is small, when simulations are initiated by applying the wind stress to a motionless mixed layer with stratification. The difference in the entrainment rate between the cases with and without LC decreases with hΔB/υL2, where υL is the velocity scale of LC. The ratio of the mixing length scale l between the cases with and without LC is close to 1 for larger Rt [=(Nl0/q)2; Rt > ∼1], but it increases to above 10 with the decrease of Rt, where N is the Brunt–Väisälä frequency and q and l0 are the velocity and length scales of turbulence in the homogeneous layer. It is also found that, in the presence of LC, the effect of stratification on vertical mixing should be parameterized in terms of Rt instead of Ri (=(N/S)2), because velocity shear S is no longer a dominant source of turbulence. The parameterization is provided by l/l0 = (1 + αRt)−1/2 with α ∼ 50, regardless of the presence of LC. However, LC makes l0 much larger than conventionally used for the boundary layer.
Semi-Adiabatic Model of the Deep Stratification and Meridional Overturning
Authors: Radko Timour , Kamenkovich Igor
Published: December 2010

An analytical model of the Atlantic deep stratification and meridional overturning circulation is presented that illustrates the dynamic coupling between the Southern Ocean and the midlatitude gyres. The model, expressed here in terms of the two-and-a-half-layer framework, predicts the stratification and meridional transport as a function of the mechanical and thermodynamic forcing at the sea surface. The approach is based on the classical elements of large-scale circulation theory—ideal thermocline, inertial western boundary currents, and eddy-controlled Antarctic Circumpolar Current (ACC) models—which are combined to produce a consistent three-dimensional view of the global overturning. The analytical tractability is achieved by assuming and subsequently verifying that the pattern of circulation in the model is largely controlled by adiabatic processes: the time-mean and eddy-induced isopycnal advection of buoyancy. The mean stratification of the lower thermocline is determined by the surface forcing in the ACC and, to a lesser extent, by the North Atlantic Deep Water formation rate. Although the vertical small-scale mixing and the diapycnal eddy-flux components can substantially influence the magnitude of overturning, their effect on the net stratification of the midlatitude ocean is surprisingly limited. The analysis in this paper suggests the interpretation of the ACC as an active lateral boundary layer that does not passively adjust to the prescribed large-scale solution but instead forcefully controls the interior pattern.
Child Abuse Experts Disagree About the Threshold for Mandated Reporting
Authors: Levi Benjamin H. , Crowell Kathryn
Published: December 2010

Context: Though reasonable suspicion serves as the standard threshold for when to report suspected child abuse, there is little guidance how to interpret the term. Objective: To examine how experts on child abuse interpret reasonable suspicion using 2 probability frameworks. Participants: Anonymous survey of clinical and research experts on child abuse. Main outcome measures: Responses on ordinal and visual analog scales quantifying the probability needed for “suspicion of child abuse” to rise to reasonable suspicion. Results: A total of 81 of 117 experts completed the survey (69% response rate, mean age 47 years, 69% female). On both the ordinal probability scale (rank order on a differential diagnosis) and the estimated probability scale (1% to 99% likelihood), experts demonstrated wide variability in defining reasonable suspicion, with no statistically significant differences found for age, race, gender, professional training, seniority, or prior education on reasonable suspicion. Conclusions: This study found no consensus in how experts on child abuse interpret reasonable suspicion.
Analysis and modeling of delamination factor in drilling glass fiber reinforced plastic using response surface methodology
Authors: Kilickap Erol
Published: December 2010

This study, through a new approach, presents a comprehensive mathematical model for correlating the interactive and higher order influences of drilling parameters on the delamination factor in drilling glass fiber reinforced plastic (GFRP) composites using response surface methodology. The purpose of this article is to investigate the influence of drilling parameters, such as cutting speed, feed, and point angle on delamination produced when drilling GFRP composite. The damage generated associated with drilling GFRP composites were observed, both at the entrance and exit during the drilling. The experiments are conducted based on Box—Behnken design. Empirical models are developed to correlate and predict the drilling parameters and delamination factor in drilling of GFRP. The developed models for delamination factor at entrance and exit are proposed that agree well with the experiment. The models can be utilized to select the level of drilling parameters. Thus time and cost were noticeably reduced.
Water sorption and mechanical performance of preheated wood/ thermoplastic composites
Authors: Kaboorani Alireza , Englund Karl R.
Published: December 2010

Wood samples heat treated at 175°C, 190°C, and 205°C with different amounts of high density polyethylene and coupling agent were used for the production of wood/plastic composites. Measuring water sorption, thickness swelling, and diffusion coefficients of composites for a 40-week period immersion in water showed that composites with wood treatment at 190°C and 205°C had considerably higher water resistance. Adding a coupling agent reduced water sorption, thickness swelling, and diffusion coefficients, more pronounced in composites with untreated wood. Measurements of flexural properties in a control state and after 4 and 12 weeks immersion periods in water proved that heat treatment is an effective way to ease detrimental effects of water on mechanical properties. Modulus of elasticity showed more sensitivity to water exposure than modulus of rupture. Strain at maximum load increased after water exposure. Treating wood at 190°C resulted in good flexural properties and excellent water resistance.
Preparation and Analysis of the Central Nervous System
Authors: Jordan William H. , Young Jamie K. , Hyten Monty J. , Hall D. Greg
Published: December 2010

For many pathologists, neuropathology is intimidating. Practical approaches for nervous tissue histologic evaluations to meet both routine and advanced study designs can lead to rewarding neuropathology efforts. Cost-effective, high-quality histologic evaluations can occur if animals are exsanguinated quickly, brains removed carefully to maintain structural integrity and avoid dark neuron artifact, immersion-fixed quickly and thoroughly, and trimmed and processed to consistently survey multiple areas. While brightfield examination of H&E-stained sections is generally sufficient for survey evaluations, epifluorescent assessment of neuronal autofluorescence facilitates recognition of neurodegeneration in H&E-stained sections. Fluoro-Jade B or specialized immunohistochemical stains may be required to answer specific questions. Evaluations require that both technical staff and pathologists have a working knowledge of a few easily identified neuroanatomic landmarks and familiarity with use of a detailed brain atlas. At least four coronal sections should be routinely surveyed from young adult rats, with evaluation of comparable areas in other laboratory animal species. This number should be at least doubled if there is reason to suspect morphologic changes in the CNS. This article focuses on technical details of efficient specimen preparation for neuropathologic evaluations involving relatively large numbers of rodents, as well as a practical approach to basic neuroanatomic site identification.
Randomized multi-modal motion planning for a humanoid robot manipulation task
Authors: Hauser Kris , Ng-Thow-Hing Victor
Published: December 2010

Robots that perform complex manipulation tasks must be able to generate strategies that make and break contact with the object. This requires reasoning in a motion space with a particular multi-modal structure, in which the state contains both a discrete mode (the contact state) and a continuous configuration (the robot and object poses). In this paper we address multi-modal motion planning in the common setting where the state is high-dimensional, and there are a continuous infinity of modes. We present a highly general algorithm, Random-MMP, that repeatedly attempts mode switches sampled at random. A major theoretical result is that Random-MMP is formally reliable and scalable, and its running time depends on certain properties of the multi-modal structure of the problem that are not explicitly dependent on dimensionality. We apply the planner to a manipulation task on the Honda humanoid robot, where the robot is asked to push an object to a desired location on a cluttered table, and the robot is restricted to switch between walking, reaching, and pushing modes. Experiments in simulation and on the real robot demonstrate that Random-MMP solves problem instances that require several carefully chosen pushes in minutes on a PC.
Motion planning under uncertainty for robotic tasks with long time horizons
Authors: Kurniawati Hanna , Yanzhu Du  , Hsu David , Wee Sun Lee
Published: December 2010

Motion planning with imperfect state information is a crucial capability for autonomous robots to operate reliably in uncertain and dynamic environments. Partially observable Markov decision processes (POMDPs) provide a principled general framework for planning under uncertainty. Using probabilistic sampling, point-based POMDP solvers have drastically improved the speed of POMDP planning, enabling us to handle moderately complex robotic tasks. However, robot motion planning tasks with long time horizons remains a severe obstacle for even the fastest point-based POMDP solvers today. This paper proposes Milestone Guided Sampling (MiGS), a new point-based POMDP solver, which exploits state space information to reduce effective planning horizons. MiGS samples a set of points, called milestones , from a robot’s state space and constructs a simplified representation of the state space from the sampled milestones. It then uses this representation of the state space to guide sampling in the belief space and tries to capture the essential features of the belief space with a small number of sampled points. Preliminary results are very promising. We tested MiGS in simulation on several difficult POMDPs that model distinct robotic tasks with long time horizons in both 2-D and 3-D environments. These POMDPs are impossible to solve with the fastest point-based solvers today, but MiGS solved them in a few minutes.
Effect of Single-Bundle and Double-Bundle Anterior Cruciate Ligament Reconstructions on Pivot-Shift Kinematics in Anterior Cruciate Ligament– and Meniscus-Deficient Knees
Authors: Musahl Volker , Bedi Asheesh , Citak Musa , O’Loughlin Padhraig , Choi Daniel , Pearle Andrew D.
Published: December 2010

Background: Recent laboratory and clinical studies report no difference between single-bundle (SB) and double-bundle (DB) anterior cruciate ligament (ACL) reconstruction.

Hypothesis: Anatomical DB ACL reconstruction would restore knee kinematics in a complex injury model of ACL–meniscus injury closer to the intact state when compared with 2 common SB ACL reconstructions.

Study Design: Controlled laboratory study.

Methods: Five fresh-frozen cadaveric hip-to-toe lower extremity specimens were used for this study (10 knees). A surgical navigation system recorded the 3-dimensional motion path of a tracked point at the center of the medial and lateral compartments during a 68-N Lachman test and a mechanized pivot-shift test. Testing was performed on the intact knee, after ACL, medial meniscus, and lateral meniscus resection and after 3 ACL reconstructions: anatomical anteromedial SB, nonanatomical SB (posterolateral tibia to anteromedial femur), and anatomical DB. Same-sized hamstring grafts were used for all reconstructions. Repeated-measures analysis of variance with a post hoc Tukey multiple-comparison test was used to compare the anterior tibial translations of the 3 grafts during laxity testing.

Results: Regarding the Lachman test, there was no difference between the anatomical anteromedial SB and DB reconstructions. For the mechanized pivot shift, anatomical DB reconstruction restored anterior tibial translation to the intact state; however, significantly greater anterior tibial translation was detected after anatomical anteromedial SB and nonanatomical SB reconstruction, compared with the intact knee. In addition, there was no difference in medial compartment translations during the pivot shift between the intact and reconstructed states.

Conclusion: Anatomical DB ACL reconstruction was able to restore intact knee kinematics during the pivot shift even in the severe injury model.

Clinical Relevance: Double-bundle ACL reconstruction procedures may be preferred in cases of high-grade instability or meniscus deficiency.