bluuebunny/crossref_metadata_2025 huggingface dataset:
Integrated Microreactors for Reaction Automation: New Approaches to Reaction Development
Authors: McMullen Jonathan P. , Jensen Klavs F.
Published: June 2010

Applications of microsystems (microreactors) in continuous-flow chemistry have expanded rapidly over the past two decades, with numerous reports of higher conversions and yields compared to conventional batch benchtop equipment. Synthesis applications are enhanced by chemical information gained from integrating microreactor components with sensors, actuators, and automated fluid handling. Moreover, miniaturized systems allow experiments on well-defined samples at conditions not easily accessed by conventional means, such as reactions at high pressure and temperatures. The wealth of synthesis information that could potentially be acquired through use of microreactors integrated with physical sensors and analytical chemistry techniques for online reaction monitoring has not yet been well explored. The increased efficiency resulting from use of continuous-flow microreactor platforms to automate reaction screening and optimization encourages a shift from current batchwise chemical reaction development to this new approach. We review advances in this new area and provide application examples of online monitoring and automation.
Gas-Phase Chemistry of Multiply Charged Bioions in Analytical Mass Spectrometry
Authors: Huang Teng-Yi , McLuckey Scott A.
Published: June 2010

Ion chemistry has long played an important role in molecular mass spectrometry (MS), as it is central to the use of MS as a structural characterization tool. With the advent of ionization methods capable of producing gaseous ions from large biomolecules, the chemistry of gaseous bioions has become a highly active area of research. Gas-phase biomolecule-ion reactions are usually driven by interactions with neutral molecules, photons, electrons, ions, or surfaces. Ion dissociation or transformation into different ion types can be achieved. The types of reaction products observed depend on the characteristics of the ions, the transformation methods, and the time frame of observation. This review focuses on the gas-phase chemistries of ions derived from the electrospray ionization of peptides, proteins, and oligonucleotides, with particular emphasis on their utility in bioanalysis. Various ion-transformation strategies, which further facilitate structural interrogation by converting ions from one type to another, are also summarized.
Cytotoxic T Cells inH. pylori-Related Gastric Autoimmunity and Gastric Lymphoma
Authors: Bergman Mathijs P. , D'Elios Mario M.
Published: June 2010

Helicobacter pyloriinfection is the major cause of gastroduodenal pathologies, but only a minority of infected patients develop gastric B-cell lymphoma, gastric autoimmunity, or other life threatening diseases, as gastric cancer or peptic ulcer. The type of host immune response againstH. pylori, particularly the cytolytic effector functions of T cells, is crucial for the outcome of the infection. T cells are potentially able to kill a target via different mechanisms, such as perforins or Fas-Fas ligand interaction. InH. pylori-infected patients with gastric autoimmunity cytolytic T cells, that cross-recognize different epitopes ofH. pyloriproteins and -ATPase autoantigen, infiltrate the gastric mucosa and lead to gastric atrophy via long-lasting activation of Fas ligand-mediated appotosis and perforin-induced cytotoxicity. On the other hand, gastric T cells from MALT lymphoma exhibit defective perforin- and Fas-Fas ligand-mediated killing of B cells, with consequent abnormal help for B-cell proliferation, suggesting that deregulated and exhaustiveH. pylori-induced T cell-dependent B-cell activation can support both the onset and the promotion of low-grade B-cell lymphoma.
Existence of Positive Solutions for a Functional Fractional Boundary Value Problem
Authors: Bai Chuanzhi
Published: June 2010

We study the existence of positive solutions for a boundary value problem of fractional‐order functional differential equations. Several new existence results are obtained.
Conservation Laws in Quantum-Correlation-Function Dynamics
Authors: Wang Wei , Takeda Mitsuo
Published: June 2010

For a complete and lucid discussion of quantum correlation, we introduced two new first-order correlation tensors defined as linear combinations of the general coherence tensors of the quantized fields and derived the associated coherence potentials governing the propagation of quantum correlation. On the basis of these quantum optical coherence tensors, we further introduced new concepts of scalar, vector and tensor densities and presented some related properties, such as conservation laws and the wave-particle duality for quantum correlation, which provide new insights into photon statistics and quantum correlation.
Second Law Analysis for a Variable Viscosity Reactive Couette Flow under Arrhenius Kinetics
Authors: Kobo N. S. , Makinde O. D.
Published: June 2010

This study investigates the inherent irreversibility associated with the Couette flow of a reacting variable viscosity combustible material under Arrhenius kinetics. The nonlinear equations of momentum and energy governing the flow system are solved both analytically using a perturbation method and numerically using the standard Newton Raphson shooting method along with a fourth‐order Runge Kutta integration algorithm to obtain the velocity and temperature distributions which essentially expedite to obtain expressions for volumetric entropy generation numbers, irreversibility distribution ratio, and the Bejan number in the flow field.
Compressed Sensing Inspired Image Reconstruction from Overlapped Projections
Authors: Yang Lin , Lu Yang , Wang Ge
Published: June 2010

The key idea discussed in this paper is to reconstruct an image from overlapped projections so that the data acquisition process can be shortened while the image quality remains essentially uncompromised. To perform image reconstruction from overlapped projections, the conventional reconstruction approach (e.g., filtered backprojection (FBP) algorithms) cannot be directly used because of two problems. First, overlapped projections represent an imaging system in terms of summed exponentials, which cannot be transformed into a linear form. Second, the overlapped measurement carries less information than the traditional line integrals. To meet these challenges, we propose a compressive sensing‐(CS‐) based iterative algorithm for reconstruction from overlapped data. This algorithm starts with a good initial guess, relies on adaptive linearization, and minimizes the total variation (TV). Then, we demonstrated the feasibility of this algorithm in numerical tests.
A School-Based Exercise Intervention Program Increases Muscle Strength in Prepubertal Boys
Authors: Stenevi-Lundgren Susanna , Daly Robin M. , Karlsson Magnus K.
Published: June 2010

This prospective controlled intervention study over 12 months evaluated the effect of exercise on muscular function, physical ability, and body composition in pre-pubertal boys. Sixty-eight boys aged 6–8 years, involved in a general school-based exercise program of 40 min per school day (200 min/week), were compared with 46 age-matched boys who participated in the general Swedish physical education curriculum of mean 60 min/week. Baseline and annual changes of body composition were measured by dual energy X-ray absorptiometry (DXA), stature, and body mass by standard equipments, isokinetic peak torque (PT) of the knee extensors, and flexors at 60 and 180 deg/sec by computerized dynamometer (Biodex) and vertical jump height (VJH) by a computerized electronic mat. The annual gain in stature and body mass was similar between the groups whereas the increase in total body and regional lean mass (P<.001) and fat mass (P<.001) was greater in the exercise group. The one-year gain in body mass-adjusted knee extensor and flexor PT at 180 deg/sec was significantly greater in the intervention group compared with the control group (P<.01, adjusted for age at baseline andP<.001, adjusted for age and muscle strength at baseline, resp.). There was no group difference in VJH. In conclusion, the increase in school-based physical education from 60 to 200 minutes per week enhances the development of lean body mass and muscle strength in pre-pubertal boys.
Pubertal Pathways in Girls Enrolled in a Contemporary British Cohort
Authors: Christensen Krista Yorita , Maisonet Mildred , Rubin Carol , Holmes Adrianne , Flanders W. Dana , Heron Jon , Golding Jean , McGeehin Michael A. , Marcus Michele
Published: June 2010

Data from the Avon Longitudinal Study of Parents and Children were used to describe initiation of secondary sexual characteristic development of girls. Tanner stages of breast and pubic hair and menarche status were self-reported via mailed questionnaires, administered from ages 8–14. Initiation pathway was categorized as breast [thelarche] or pubic hair [pubarche] development alone, or synchronous. Average ages at beginning breast and pubic hair development were estimated using survival analysis. Factors associated with initiation pathway were assessed using logistic regression. Among the 3938 participants, the median ages at beginning breast and pubic hair development were 10.19 (95% CI: 10.14–10.24) and 10.95 (95% CI: 10.90–11.00) years. Synchronous initiation was the most commonly reported pathway (46.3%), followed by thelarche (42.1%). Girls in the pubarche pathway were less likely to be obese or overweight at age 8 or have an overweight or obese mother. Girls in the thelarche pathway were less likely to be of nonwhite race or be the third born or later child.
Conditions for Oscillation of a Neutral Differential Equation
Authors: Yan Weiping , Yan Jurang
Published: June 2010

For a neutral differential equation with positive and changeable sign
coefficients
[x(t)−a(t)x(δ(t))]′ + p(t)F(x(τ(t))) − q(t)G(x(σ(t))) = 0,
oscillation criteria are established, where q(t) is not required as nonnegative. Several new results are obtained.
Topological Entropy of Cournot‐Puu Duopoly
Authors: Cánovas Jose S. , López Medina David
Published: June 2010

The aim of this paper is to analyze a classical duopoly model introduced by Tönu Puu in 1991. For that, we compute the topological entropy of the model and characterize those parameter values with positive entropy. Although topological entropy is a measure of the dynamical complexity of the model, we will show that such complexity could not be observed.
Energy from Waste: Reuse of Compost Heat as a Source of Renewable Energy
Authors: Irvine G. , Lamont E. R. , Antizar-Ladislao B.
Published: June 2010

An in-vessel tunnel composting facility in Scotland was used to investigate the potential for collection and reuse of compost heat as a source of renewable energy. The amount of energy offered by the compost was calculated and seasonal variations analysed. A heat exchanger was designed in order to collect and transfer the heat. This allowed heated water of C to be obtained. The temperature could be further increased to above C by passing it through multiple tunnels in series. Estimated costs for installing and running the system were calculated. In order to analyse these costs alternative solar thermal and ground source heat pump systems were also designed. The levels of supply and economic performance were then compared. A capital cost of 11,662 and operating cost of 1,039 per year were estimated, resulting in a cost of 0.50 per kWh for domestic water and 0.10 per kWh for spatial heat. Using the heat of the compost was found to provide the most reliable level of supply at a similar price to its rivals.
Measuring the Cytochrome c Nitrite Reductase Activity—Practical Considerations on the Enzyme Assays
Authors: Silveira Célia M. , Besson Stéphane , Moura Isabel , Moura José J. G. , Almeida M. Gabriela
Published: June 2010

The cytochrome c nitrite reductase (ccNiR) from Desulfovibrio desulfuricans ATCC 27774 is
able to reduce nitrite to ammonia in a six‐electron transfer reaction. Although extensively
characterized from the spectroscopic and structural points‐of‐view, some of its kinetic aspects
are still under explored. In this work the kinetic behaviour of ccNiR has been evaluated in a
systematic manner using two different spectrophotometric assays carried out in the presence of
different redox mediators and a direct electrochemical approach. Solution assays have proved
that the specific activity of ccNiR decreases with the reduction potential of the electronic carriers
and ammonium is always the main product of nitrite reduction. The catalytic parameters were
discussed on the basis of the mediator reducing power and also taking into account the location
of their putative docking sites with ccNiR. Due to the fast kinetics of ccNiR, electron delivering
from reduced electron donors is rate‐limiting in all spectrophotometric assays, so the estimated
kinetic constants are apparent only. Nevertheless, this limitation could be overcome by using a
direct electrochemical approach which shows that the binding affinity for nitrite decreases whilst
turnover increases with the reductive driving force.
Use of Sawing Waste from Zeolitic Tuffs in the Manufacture of Ceramics
Authors: Pansini M. , de Gennaro R. , Parlato L. , de'Gennaro M. , Langella A. , Marocco A. , Cappelletti P. , Mercurio M.
Published: June 2010

This paper investigates the thermal transformation of powders of volcanic tuffs that are used as building stones and aims at thermally transforming them into ceramics. The following positive indications concerning this thermal transformation were found: (1) the structural evolution which brings products similar to traditional ceramics, (2) the good ability to give rise to dense and compact final products, and (3) the good mechanical properties and the lovely appearance of the final products. Nevertheless, the high values of linear shrinkages recorded in this work seem to strongly hinder the thermal transformation of this powder-like waste into ceramics. However, mixing this by-product with other powder-like waste exhibiting higher-dimensional stability, such as those deriving from sawing of granites, appears proper.
Socioeconomic Impacts on Survival Differ by Race/Ethnicity among Adolescents and Young Adults with Non-Hodgkin's Lymphoma
Authors: Kent Erin E. , Morris Rebecca A. , Largent Joan A. , Ziogas Argyrios , Sender Leonard S. , Anton-Culver Hoda
Published: June 2010

Shorter survival has been associated with low socioeconomic status (SES) among elderly non-Hodgkin's lymphoma (NHL) patients; however it remains unknown whether the same relationship holds for younger patients. We explored the California Cancer Registry (CCR), to investigate this relationship in adolescent and young adult (AYA) NHL patients diagnosed from 1996 to 2005. A case-only survival analysis was conducted to examine demographic and clinical variables hypothesized to be related to survival. Included in the final analysis were 3,489 incident NHL cases. In the multivariate analyses, all-cause mortality (ACM) was higher in individuals who had later stage at diagnosis (P<.05) or did not receive first-course chemotherapy (P<.05). There was also a significant gradient decrease in survival, with higher ACM at each decreasing quintile of SES (P<.001). Overall results were similar for lymphoma-specific mortality. In the race/ethnicity stratified analyses, only non-Hispanic Whites (NHWs) had a significant SES-ACM trend (P<.001). Reduced overall and lymphoma-specific survival was associated with lower SES in AYAs with NHL, although a significant trend was only observed for NHWs.
The Emerging Role of HLA-E-Restricted CD8+T Lymphocytes in the Adaptive Immune Response to Pathogens and Tumors
Authors: Pietra Gabriella , Romagnani Chiara , Manzini Claudia , Moretta Lorenzo , Mingari Maria Cristina
Published: June 2010

Human leukocyte antigen (HLA)-E is a nonclassical major histocompatibility complex (MHC) class I molecule of limited sequence variability that is expressed by most tissues albeit at low levels. HLA-E has been first described as the ligand of CD94/NKG2 receptors expressed mainly by natural killer (NK) cells, thus confining its role to the regulation of NK-cell function. However, recent evidences obtained by our and other groups indicate that HLA-E complexed with peptides can interact withαβT-cell receptor (TCR) expressed on CD8+T cells. Although, HLA-E displays a selective preference for nonameric peptides, derived from the leader sequence of various HLA class I alleles, several reports indicate that it can present also “noncanonical” peptides derived from both stress-related and pathogen-associated proteins. Because HLA-E displays binding specificity for innate CD94/NKG2 receptors, as well as all the features of an antigen-presenting molecule, its role in both natural and acquired immune responses has recently been re-evaluated.
Surgical Treatment of Pancreatic Neuroendocrine Tumors: Report of 112 Cases
Authors: Gao Chuntao , Fu Xiuqing , Pan Yi , Li Qiang
Published: June 2010

Objectives: To review the clinical data of a group of patients with pancreatic neuroendocrine tumors (pNETs) and to investigate the role of surgery in the treatment for pNETs by analyzing clinical manifestations and postoperative course of this rare disease. Methods: A total of 112 patients (aged 21–76 years; 45 males) who underwent treatment between 1980 and 2003 were recruited in this study. Patients’ data related to demographics and characteristics, diagnostic studies, surgical and tumor characteristics and survival were retrospectively reviewed. Results: Forty-six patients (41.1%) had a well-differentiated neuroendocrine tumor (WDT), 44 (48.2%) a well-differentiated neuroendocrine carcinoma (WD-Ca) and 12 (10.7%) a poorly differentiated neuroendocrine carcinoma (PD-Ca). Nonfunctional tumors were seen in 65 (58.0%) patients, whereas functional tumors were found in 47 (42.0%) patients, including 26 insulinomas, 17 gastrinomas, 2 VIPomas, 1 glucagonoma, and 1 ACTHoma. The sensitivity of computed tomography was 87.1%. Surgical resection was performed in 99 (88.4%) patients. Thirty-eight (33.9%) patients underwent partial pancreaticoduodenectomy, 32 (28.6%) had distal pancreatectomy and 29 (25.9%) underwent enucleation. No surgery-related death occurred. The common postoperative complications were pancreatic fistula (15.2%), wound infection (13.4%) and delayed gastric emptying (6.3%). Three (5%) patients had reoperation due to intra-abdominal abscess and postoperative hemorrhage. Twenty-six (55.3%) of the 47 functional tumors were malignant, whereas 40 (61.5%) of the 65 nonfunctional tumors were malignant. Survival was significantly related to the type of neuroendocrine tumor (p = 0.001). The overall 5-year actual survival rate of patients with WD-Ca (n = 54) was 56%, significantly less than that of patients with WDT (n = 46, 91%, p = 0.001). All the patients of PD-Ca (n = 12) group died in 5 years. The 5-year survival rate differed significantly between patients with tumor node metastasis (TNM) stage I and II disease and those with stage III and IV tumors (p = 0.011). Patients with stage III had better prognosis than those with stage IV tumors (p = 0.007). Patients’ long-term survival was closely correlated with vascular invasion (p = 0.008) and resection margin (p = 0.004). Conclusions: PNETs can be safely resected. Microscopic vascular invasion and positive resection margin are helpful for predicting patient survival. Malignant cases should be treated with aggressive radical surgery to achieve complete tumor resection and potential for long-term survival.
Perforated Peptic Ulcer Disease: A Review of History and Treatment
Authors: Bertleff Mariëtta J.O.E. , Lange Johan F.
Published: June 2010

Background: In the last one hundred years much has been written on peptic ulcer disease and the treatment options for one of its most common complications: perforation. The reason for reviewing the literature was evaluating most common ideas on how to treat perforated peptic ulcers (PPU) in general, opinions on conservative treatment and surgical treatment and summarizing ideas about necessary pre-, per- and postoperative proceedings. Method: All relevant articles found by Medline, Ovid and PubMed search were used. Results: A hundred articles written between 1929 and 2009 were reviewed. Of these, 9 were about the history of treatment, 7 about conservative treatment, and 26 were about the surgical procedure of which 8 were addressing laparoscopic correction. Overall there is no consensus, but some advice is given. For conservative treatment there are only a few indications. Use of an omental patch is recommended, irrigation and drainage are not. Laparoscopic correction of PPU as well as for definitive ulcer surgery has many advantages. Conclusions: Surgery for PPU is still a subject of debate despite more than an era of published expertise, indicating the need for establishing guidelines.
Reverse Double-Stapling End-to-End Esophagogastrostomy in Proximal Gastrectomy
Authors: Kong Seong-Ho , Kim Jong Won , Lee Hyuk-Joon , Kim Woo Ho , Lee Kuhn Uk , Yang Han-Kwang
Published: June 2010

Background: Proximal gastrectomy is a surgical option for proximally located early gastric cancer. We present a new double-stapling method for proximal gastrectomy and esophagogastrostomy. Methods: We examined the safety of proximal gastrectomy by analyzing the lymph node metastasis rate in 53 patients who underwent total gastrectomy due to proximally located early gastric cancer from January 2004 to December 2008. We applied the double-stapling method used in distal gastrectomy reversely to proximal gastrectomy and esophagogastrostomy in 15 patients. Results: Retrospective analysis showed that proximal early gastric cancer metastasizes to only lymph node station 2, 3 and 7 which were completely removed during proximal gastrectomy. Fifteen patients underwent proximal gastrectomy using a new method which left no gastrostomy wound for the insertion of a circular stapler in the remaining stomach. The median operation time was 156.5 min and median postoperative hospital stay was 8.0 days. There were only 2 cases of wound complications during hospital stay. Two cases of anastomosis site strictures which developed after discharge were successfully treated with balloon dilatation. Conclusion: We presented a new ‘reverse double-stapling method’ for proximal gastrectomy, which seems to be a fast and feasible method that leaves no gastrostomy wound in the remaining stomach.
The Vascular Stapler in Uncinate Process Division during Pancreaticoduodenectomy: Technical Considerations and Results
Authors: D’souza Melroy A. , Singh Kailash , Hawaldar Rohini V. , Shukla Parul J. , Shrikhande Shailesh V.
Published: June 2010

Background: Few studies describing the use of stapling devices for uncinate process division during pancreaticoduodenectomy (PD) have data regarding outcomes. Our aim is to discuss our technique and the peri-operative outcomes with the use of the linear vascular stapler for division of the uncinate process during PD. Materials and Methods: 19 consecutive patients who underwent stapler division of the uncinate process (‘stapler’ group) were compared to 20 consecutive patients operated without stapler (‘no-stapler’ group). Results: The overall surgical morbidity in the no-stapler group was 25% (5/20) and 31.6% (6/19) in the stapler group (p = 0.731). The mean blood loss in the no-stapler group was 1,077.5 ± 594 ml compared to 778 ± 302 ml in the stapler group (p = 0.113). The mean operative duration was 498 ± 105 min in the no-stapler group and 490 ± 60 min in the stapler group (p = 0.773). The average number of lymph nodes retrieved was 6.1 ± 3 in the no-stapler group versus 5.9 ± 4 in the stapler group (p = 0.627). Neither group had positive resection margins. Conclusion: Stapler division of the uncinate process for selected periampullary tumours compares well with the conventional method, has comparable peri-operative outcomes without compromising oncological radicality and has the potential to simplify uncinate resection.
Long-Term Results of the Cut-Closed-Reconnected Roux Loop for Enterogastric Reflux
Authors: Kummer Erik W. , Gerritsen Jos J.G.M. , Klaase Joost M.
Published: June 2010

Background: The aim of this study was to present the long-term results of the cut-closed-reconnected (CCR)-Roux procedure for reflux gastritis. Methods: A retrospective analysis was performed on 14 patients with proven reflux gastritis and/or esophagitis who were treated at our institution with a CCR-Roux procedure between 1992 and 1997. Results: The closure of the afferent loop in the CCR-Roux procedure is effective and permanent. The CCR-Roux patients did not need a rest gastrectomy. No signs of Roux stasis syndrome were seen. There was a consistent weight gain at 2 and 5 years of follow-up. These results permit a comparison with those of the Roux-Y procedure and other alternative procedures as well. Conclusion: In the long run, the CCR-Roux procedure is effective in the treatment of reflux gastritis.
A Simple Novel Model to Predict Hospital Mortality, Surgical Site Infection, and Pneumonia in Elderly Patients Undergoing Operation
Authors: Huang Ting-Shuo , Hu Fu-Chang , Fan Chung-Wei , Lee Chun-Hui , Jwo Shyh-Chuan , Chen Huang-Yang
Published: June 2010

Background/Aims: Predicting models of operative morbidity and mortality in the geriatric population are important in the prevention of adverse surgical outcomes. Methods: A retrospective review of medical records was performed for patients over 80 years of age who underwent gastrointestinal surgery from 1998 to 2008. Results: 215 patients were identified with a mean age of 83.7 years. Overall morbidity and mortality rates were 48.8 and 14.4%, respectively. Multivariate logistic regression analysis revealed that serum albumin levels [odds ratio (OR) = 0.367, p = 0.0267], postoperative pneumonia (OR = 3.471, p = 0.0101), hollow organ perforation or anastomosis combined with leakage (OR = 7.600, p = 0.0126), and preoperative systemic inflammatory response syndrome (OR = 3.186, p = 0.0323) were significant predictors of hospital mortality. Moreover, albumin (OR = 0.270, p = 0.0002) and physical disability (OR = 3.802, p = 0.0009) were significant predictors of postoperative pneumonia, and albumin (OR = 0.491, p = 0.0212) and enterotomy (OR = 3.335, p = 0.0208) were significant predictors of surgical site infections. Conclusion: This study provides novel predicting models to identify the elderly surgical patients at high risk, who should receive more intensive preventive and perioperative care.
Sun-Induced Changes in Stratum Corneum Function Are Gender and Dose Dependent in a Chinese Population
Authors: Liu Z. , Fluhr J.W. , Song S.P. , Sun Z. , Wang H. , Shi Y.J. , Elias P.M. , Man M.-Q.
Published: June 2010

Previous studies have demonstrated that UVB radiation changes the epidermal permeability barrier and stratum corneum (SC) hydration. It is well known that sun exposure causes erythema, sunburn and melanoma. However, whether daily sun exposure alters SC integrity and epidermal permeability barrier function is largely unknown, especially in Chinese subjects. In the present study, we assess the SC integrity, SC hydration and epidermal permeability barrier function following various doses of sun exposure. A total of 258 subjects (124 males and 134 females) aged 18–50 years were enrolled. A multifunctional skin physiology monitor (Courage & Khazaka MPA5) was used to measure SC hydration and transepidermal water loss (TEWL) on the forearms. In males, basal TEWL was higher with higher doses of sun exposure than with lower doses and control, whereas in females, basal TEWL was higher with lower doses of sun exposure than with higher doses and control. In the group with higher doses of sun exposure, TEWL in females was significantly lower than that in males. The barrier recovery was faster in females than in males in both control and lower-dose groups. In both males and females, barrier recovery was delayed with higher doses of sun exposure. In males, sun exposure did not alter SC hydration, while in females SC hydration was lower with lower doses of sun exposure as compared with control and higher doses of sun exposure. These results demonstrated that sun-induced changes in SC function and SC hydration vary with gender and the extent of sun exposure.
Comprehensive Peroxidase-Based Hematologic Profiling for the Prediction of 1-Year Myocardial Infarction and Death
Authors: Brennan Marie-Luise , Reddy Anupama , Tang W. H. Wilson , Wu Yuping , Brennan Danielle M. , Hsu Amy , Mann Shirley A. , Hammer Peter L. , Hazen Stanley L.
Published: June 2010

Background—

Recognition of biological patterns holds promise for improved identification of patients at risk for myocardial infarction (MI) and death. We hypothesized that identifying high- and low-risk patterns from a broad spectrum of hematologic phenotypic data related to leukocyte peroxidase-, erythrocyte- and platelet-related parameters may better predict future cardiovascular risk in stable cardiac patients than traditional risk factors alone.

Methods and Results—

Stable patients (n=7369) undergoing elective cardiac evaluation at a tertiary care center were enrolled. A model (PEROX) that predicts incident 1-year death and MI was derived from standard clinical data combined with information captured by a high-throughput peroxidase-based hematology analyzer during performance of a complete blood count with differential. The PEROX model was developed using a random sampling of subjects in a derivation cohort (n=5895) and then independently validated in a nonoverlapping validation cohort (n=1474). Twenty-three high-risk (observed in ≥10% of subjects with events) and 24 low-risk (observed in ≥10% of subjects without events) patterns were identified in the derivation cohort. Erythrocyte- and leukocyte (peroxidase)-derived parameters dominated the variables predicting risk of death, whereas variables in MI risk patterns included traditional cardiac risk factors and elements from all blood cell lineages. Within the validation cohort, the PEROX model demonstrated superior prognostic accuracy (78%) for 1-year risk of death or MI compared with traditional risk factors alone (67%). Furthermore, the PEROX model reclassified 23.5% (
P
<0.001) of patients to different risk categories for death/MI when added to traditional risk factors.

Conclusion—

Comprehensive pattern recognition of high- and low-risk clusters of clinical, biochemical, and hematologic parameters provided incremental prognostic value in stable patients having elective diagnostic cardiac catheterization for 1-year risks of death and MI.
Exercise Pulmonary Hypertension in Asymptomatic Degenerative Mitral Regurgitation
Authors: Magne Julien , Lancellotti Patrizio , Piérard Luc A.
Published: June 2010

Background—

Current guidelines recommend mitral valve surgery for asymptomatic patients with severe degenerative mitral regurgitation and preserved left ventricular systolic function when exercise pulmonary hypertension (PHT) is present. However, the determinants of exercise PHT have not been evaluated. The aim of this study was to identify the echocardiographic predictors of exercise PHT and the impact on symptoms.

Methods and Results—

Comprehensive resting and exercise transthoracic echocardiography was performed in 78 consecutive patients (age, 61±13 years; 56% men) with at least moderate degenerative mitral regurgitation (effective regurgitant orifice area =43±20 mm
2
; regurgitant volume =71±27 mL). Exercise PHT was defined as a systolic pulmonary arterial pressure (SPAP) >60 mm Hg. Exercise PHT was present in 46% patients. In multivariable analysis, exercise effective regurgitant orifice was an independent determinant of exercise SPAP (
P
<0.0001) and exercise PHT (
P
=0.002). Resting PHT and exercise PHT were associated with markedly reduced 2-year symptom-free survival (36±14% versus 59±7%,
P
=0.04; 35±8% versus 75±7%,
P
<0.0001). After adjustment, although the impact of resting PHT was no longer significant, exercise PHT was identified as an independent predictor of the occurrence of symptoms (hazard ratio=3.4;
P
=0.002). Receiver-operating characteristics curves revealed that exercise PHT (SPAP >56 mm Hg) was more accurate than resting PHT (SPAP >36 mm Hg) in predicting the occurrence of symptoms during follow-up (
P
=0.032).

Conclusions—

Exercise PHT is frequent in patients with asymptomatic degenerative mitral regurgitation. Exercise mitral regurgitation severity is a strong independent predictor of both exercise SPAP and exercise PHT. Exercise PHT is associated with markedly low 2-year symptom-free survival, emphasizing the use of exercise echocardiography. An exercise SPAP >56 mm Hg accurately predicts the occurrence of symptoms.
Kallistatin Inhibits Vascular Inflammation by Antagonizing Tumor Necrosis Factor-α–Induced Nuclear Factor κB Activation
Authors: Yin Hang , Gao Lin , Shen Bo , Chao Lee , Chao Julie
Published: June 2010

Kallistatin is a plasma protein with anti-inflammatory properties. In this study, we investigated the role and mechanisms of kallistatin in inhibiting endothelial inflammation through its heparin-binding domain. We showed that recombinant wild-type kallistatin dose-dependently competed with tumor necrosis factor (TNF)-α binding to TNF-α receptor in endothelial cells, whereas kallistatin mutant at the heparin-binding domain had no effect. Kallistatin, but not kallistatin mutant at the heparin-binding domain, abrogated TNF-α–induced endothelial cell activation, as evidenced by inhibition of TNF receptor 1–associated death domain protein activation, inhibitor of nuclear factor κB-α degradation, nuclear factor κB translocation, and p38 mitogen-activated protein kinase phosphorylation, as well as cell adhesion molecule and cytokine expression. Moreover, kallistatin, but not kallistatin mutant at the heparin-binding domain, inhibited TNF-α–induced human monocytic THP-1 cell adhesion to endothelial cells and prevented vascular endothelial growth factor–induced endothelial permeability. In mice, kallistatin gene delivery prevented vascular leakage provoked by complement factor C5a, whereas delivery of kallistatin heparin mutant gene had no effect. Similarly, gene transfer of kallistatin, but not the kallistatin heparin mutant, inhibited collagen/adjuvant-induced arthritis in rats. These results indicate that kallistatin’s heparin-binding site plays an essential role in preventing TNF-α–mediated endothelial activation and reducing vascular endothelial growth factor–induced vascular permeability, resulting in attenuation of vascular inflammation in cultured endothelial cells and animal models. This study identifies a protective role of kallistatin in vascular injury, thereby implicating the therapeutic potential of kallistatin for vascular and inflammatory diseases.
Rainfall Reinforcement Associated with Landfalling Tropical Cyclones
Authors: Dong Meiying , Chen Lianshou , Li Ying , Lu Chungu
Published: June 2010

Landfalling tropical cyclones (TCs) often bring about heavy rainfall, which typically decreases with the weakening of the TCs. However, some TCs may suddenly be reinvigorated after they become remnants over land. Such TCs may produce even stronger rains than those at the time of their landfall. This reinvigorating phenomenon is known as “rainfall reinforcement associated with landfalling tropical cyclones” (RRLTC). The TCs triggering rainfall reinforcement account for 9.7% of the total number of TCs that make landfall on mainland China and often cause problems and surprises for forecasters. The TCs with rainfall reinforcement mostly make landfall in the area of the southeastern coast of China and move primarily along two tracks, spreading northward or westward. RRLTC often occurs in the remnant of a tropical depression that has already been downgraded from typhoon intensity, particularly in a period when the remnant has slowed down or even stagnated. The highest frequency of RRLTC occurrence is during the third day after landfall and in the northeast quadrant of a TC moving northward and the southwest quadrants of a TC moving westward.

Diagnostic analysis shows that an RRLTC with a northward track can be mainly attributed to the interaction between westerly troughs and the tropical cyclone. In this way, a remnant gains baroclinic energy from the midlatitude trough. Such an interaction does not appear for northward track TCs without rainfall reinforcement. Rainfall reinforcement for TCs with a westward track is mainly due to the interaction between monsoon surge cloud clusters and tropical cyclones, which is favorable for moisture and latent heat gain. Analyses show that the westward TCs would not have rainfall reinforcement without such an interaction. RRLTC requires new energy transport into TCs. The results of the present study indicate that baroclinic potential energy and latent heat are the two major energy sources that will trigger the remnant revival and rainfall reinforcement. Land surface topography also plays an important role in increasing the rainfall of TCs.
Direct Observations of Coherent Backscatter of Radar Waves in Precipitation
Authors: Jameson A. R. , Kostinski A. B.
Published: June 2010

In previous work, it was argued that a source of radar coherent scatter occurs in the direction perpendicular to the direction of wave propagation because of the presence of grids of enhanced particle concentrations with spatial periodicities in resonance with the radar wavelength. While convincing, the evidence thus far has been indirect. In this work the authors now present direct observations of radar coherent backscattered signals in precipitation in the direction of wave propagation.

The theory is developed for the cross-correlation function of the complex amplitudes in the direction of propagation calculated for nearest neighbor range bins. Data are analyzed in snow and in rain. The results agree with the earlier conclusions in the previous work, namely that coherent scatter occurs in both rain and snow, that it is larger in snow than it is in rain, and that it can be significant at times.
An Evaluation of Rainfall Frequency and Intensity over the Australian Region in a Global Climate Model
Authors: Brown Josephine R. , Jakob Christian , Haynes John M.
Published: June 2010

Observed regional rainfall characteristics can be analyzed by examining both the frequency and intensity of different categories of rainfall. A complementary approach is to consider rainfall characteristics associated with regional synoptic regimes. These two approaches are combined here to examine daily rainfall characteristics over the Australian region, providing a target for model simulations. Using gridded daily rainfall data for the period 1997–2007, rainfall at each grid point and averaged over several sites is decomposed into the frequency of rainfall events and the intensity of rainfall associated with each event. Daily sea level pressure is classified using a self-organizing map, and rainfall on corresponding days is assigned to the resulting synoptic regimes. This technique is then used to evaluate rainfall in the new Australian Community Climate and Earth-System Simulator (ACCESS) global climate model and separate the influence of large-scale circulation errors and errors due to the representation of subgrid-scale physical processes. The model exhibits similar biases to many other global climate models, simulating too frequent light rainfall and heavy rainfall of insufficient intensity. These errors are associated with particular synoptic regimes over different sectors of the Australian continent and surrounding oceans. The model simulates only weak convective rainfall over land during the summer monsoon, and heavy rainfall associated with frontal systems over southern Australia is also not simulated. As the model captures the structure and frequency of synoptic patterns, but not the associated rainfall intensity or frequency, it is likely that the source of the rainfall errors lies in model physical parameterizations rather than large-scale dynamics.
Circulation, Heat, and Freshwater Transport at 36°N in the Atlantic
Authors: McDonagh Elaine L. , McLeod Paula , King Brian A. , Bryden Harry L. , Valdés Sinhué Torres
Published: June 2010

In May and June 2005, a transatlantic hydrographic section along 36°N was occupied. A velocity field is calculated using inverse methods. The derived 36°N circulation has an overturning transport (maximum in the overturning streamfunction) of 16.6 Sv (1 Sv ≡ 106 m3 s−1) at 1070 m. The heat transport across the section, 1.14 ± 0.12 PW, is partitioned into overturning and horizontal heat transports of 0.75 and 0.39 PW, respectively. The horizontal heat flux is set by variability at the gyre rather than by mesoscale. The freshwater flux across the section is 1.55 ± 0.18 Sv southward based on a 0.8-Sv flow from the Pacific through the Bering Strait at a salinity of 32.5 psu. The oceanic divergence of freshwater implies a net input of freshwater to the ocean of 0.75 Sv over the North Atlantic and Arctic between 36°N and the Bering Strait. Most (85%) of the recently ventilated upper North Atlantic Deep Water (water originating in the Labrador Sea) transport across the section occurs in the deep western boundary current rather than being associated with an interior pathway to the west of the mid-Atlantic ridge.
Composite Analysis of North Atlantic Extratropical Cyclones in NCEP–NCAR Reanalysis Data
Authors: Rudeva Irina , Gulev Sergey K.
Published: June 2010

Composite analysis of North Atlantic midlatitudinal winter cyclones is performed using NCEP–NCAR reanalysis data for the 60-yr period from 1948 to 2007. The composites were developed using an advanced methodology involving the coordinate transform of cyclones into a nondimensional azimuthal coordinate system and the further collocation of fields. Composite analysis is performed for air–sea turbulent fluxes, heat content, precipitable water, and precipitation for 576 oceanic cyclones generated in the Gulf Stream area in winter (January–March) from 1948 to 2007. For the region of cyclone generation over the Gulf Stream, composites were analyzed for different cyclone intensities. Over the whole North Atlantic, composites were developed throughout the life cycle and for different cyclone types classified by the regions of their migration. These classifications allow the case-to-case variability to be minimized and the robustness of the composite to be boosted. In the region of cyclone generation over the Gulf Stream, characteristics of the composites strongly depend on the cyclone intensity quantified through the radial sea level pressure difference between the cyclone’s edge and its center. Stronger cyclone intensity implies larger turbulent fluxes in the rear of a cyclone and stronger precipitation in the forward part. Cyclones gradually dry with the water content and precipitation rate decreasing by about 40% and 50%–70%, respectively, during the lifetime. Although composites of air–sea turbulent fluxes show locally very strong positive fluxes in the rear part of the cyclone, the total air–sea turbulent fluxes provided by cyclones are not significantly different from the averaged background fluxes. This shows that the formation of extreme air–sea fluxes by cyclones is connected to the larger-scale circulation conditions, particularly to the cyclone–anticyclone transition zones.
Bias Correction and Multiensemble in the NAEFS Context or How to Get a “Free Calibration” through a Multiensemble Approach
Authors: Candille Guillem , Beauregard Stéphane , Gagnon Normand
Published: June 2010

Previous studies have shown that the raw combination (i.e., the combination of the direct output model without any postprocessing procedure) of the National Centers for Environmental Prediction (NCEP) and Meteorological Service of Canada (MSC) ensemble prediction systems (EPS) improves the probabilistic forecast both in terms of reliability and resolution. This combination palliates the lack of reliability of the NCEP EPS because of the too small dispersion of the predicted ensemble and the lack of probabilistic resolution of the MSC EPS. Such a multiensemble, called the North American Ensemble Forecast System (NAEFS), especially shows bias reductions and dispersion improvements that could only come from the combination of different forecast errors. It is then legitimate to wonder whether these improvements in terms of biases and dispersions, and by extension the skill improvements, are only due to the balancing between opposite model errors.

In the NAEFS framework, bias corrections “on the fly,” where the bias is updated over time, are applied to the operational EPSs. Each model of the EPS components (NCEP/MSC) is individually bias corrected against its own analysis with the same process. The bias correction improves the reliability of each EPS component. It also slightly improves the accuracy of the predicted ensembles and thus the probabilistic resolution of the forecasts. Once the EPSs are combined, the improvements due to the bias correction are not so obvious, tending to show that the success of the multiensemble method does not only come from the cancellation of different biases. This study also shows that the combination of the raw EPS components (NAEFS) is generally better than either the bias corrected NCEP or MSC ensembles.
The Vulnerability of Mobile Home Residents in Tornado Disasters: The 2008 Super Tuesday Tornado in Macon County, Tennessee
Authors: Chaney Philip L. , Weaver Greg S.
Published: June 2010

Mobile home residents are known to be highly vulnerable to tornadoes and account for a considerable portion of tornado-related fatalities. The problem is partially related to the limited protection provided by the structure; however, shortcomings in preparedness and response to warnings may also play a role. This study investigated mobile home resident preparedness and responses to warnings for identifying areas where they might be more vulnerable than permanent home residents (brick and wood-frame houses). The study site was Macon County, Tennessee, which reported the highest number of fatalities during the 2008 Super Tuesday tornado outbreak. A post-disaster survey was conducted within days of the disaster, and the study group included 127 local residents: 35% mobile home (MH) residents, 61% permanent home (PH) residents, and 4% other. An unconditional exact test was used to test for statistical significance (0.05 level) because the sample was nonrandom. The MH residents were less prepared than the PH residents in all six categories evaluated. The difference was significant in having participated in a tornado drill, having a tornado-resistant shelter on the premises, and having an emergency response plan for seeking shelter. The MH residents were also less likely to follow the plan, and the difference was significant. Furthermore, the MH residents were much less likely to take shelter in a safe location. Preparedness factors that promoted higher evacuation rates among MH residents included having participated in a tornado drill, understanding the definition of a tornado warning, and having a plan for seeking shelter.
Moderate Physical Activity Is Associated With Lower ApoB/ApoA-I Ratios Independently of Other Risk Factors in Healthy, Middle-Aged Men
Authors: Behre CarlJohan , Bergström Göran , Schmidt Caroline
Published: June 2010

Low-density lipoprotein is recognized as a primary vascular risk factor. However, recent data favor apolipoprotein (apo)B and apoA-I as risk factors with higher predictive values than conventional lipids. We investigated how leisure-time physical activity relates to the serum apoB/apoA-I ratio in middle-aged men. The results showed that compared with a sedentary lifestyle, moderate physical activity was associated with a decreased apoB/apoA-I ratio (1.01 ± 0.28 vs 0.87 ± 0.24, P < .05) and increased apoA-I levels (1.30 ± 0.20 g/L vs 1.43 ± 0.22 g/L, P < .05), whereas vigorous activity was required to observe a reduction in apoB levels (1.27 ± 0.28 g/L vs 1.14 ± 0.24 g/L, P < .05). A covariate analysis showed that leisure time physical activity was also associated with reduced apoB/apoA-I ratios after adjustment for smoking, systolic blood pressure and waist circumference. Importantly, this association was seen at moderate levels of physical activity, supporting the notion that some activity is better than none.