bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving Ballistic Performance of Polyurethane Foam by Nanoparticle Reinforcement
Authors: Uddin M. F. , Mahfuz H. , Zainuddin S. , Jeelani S.
Published: January 2010

We report improving ballistic performance of polyurethane foam by reinforcing it with nanoscaleTiO2particles. Particles were dispersed through a sonic cavitation process and the loading of particles was 3 wt% of the total polymer. Once foams were reinforced, sandwich panels were made and impacted with fragment simulating projectiles (FSPs) in a 1.5-inch gas gun. Projectile speed was set up to have complete penetration of the target in each experiment. Test results have indicated that sandwich with nanophased cores absorbed about 20% more kinetic energy than their neat counterpart. The corresponding increase in ballistic limit was around 12% over the neat control samples. The penetration phenomenon was also monitored using a high-speed camera. Analyses of digital images showed that FSP remained inside the nanophased sandwich for about 7 microseconds longer than that of a neat sandwich demonstrating improved energy absorption capability of the nanoparticle reinforced core. Failure modes for energy absorption have been investigated through a microscope and high-speed images.
The Impact on Geographic Location Accuracy due to Different Satellite Orbit Ephemerides
Authors: Celestino Claudia C. , Sousa Cristina T. , Yamaguti Wilson , Kuga Helio Koiti
Published: January 2010

The current Brazilian System of Environmental Data Collection is composed of several satellites (SCD‐1 and 2, CBERS‐2 and 2B), Data Collection Platforms (DCPs) spread mostly over the Brazilian territory, and ground reception stations located in Cuiabá and Alcântara. An essential functionality offered to the users is the geographic location of these DCPs. The location is computed by the in‐house developed “GEOLOC” program which processes the onboard measured Doppler shifts suffered by the signal transmitted by the DCPs. These data are relayed and stored on ground when the satellite passes over the receiving stations.
Another important input data to GEOLOC are the orbit ephemeris of the satellite corresponding to the Doppler data. In this work, the impact on the geographic location accuracy when using orbit ephemeris which can be obtained through several sources is assessed. First, this evaluation is performed by computer simulation of the Doppler data, corresponding to real existing satellite passes. Then real Doppler data are used to assess the performance of the location system. The results indicate that the use of precise ephemeris can improve the performance of GEOLOC by reducing the location errors, and such conclusion can then be extended to similar location systems.
Rikkunshito and Ghrelin
Authors: Hattori Tomohisa
Published: January 2010

Rikkunshito is a popular Japanese traditional medicine that is prescribed in Japan to treat various gastrointestinal tract disorders. In a double-blind controlled study, rikkunshito significantly ameliorated dysmotility-like dyspepsia and brought about a generalized improvement in upper gastric symptoms such as nausea and anorexia when compared with a control group. Several studies in rats have shown enhanced gastric emptying and a protective effect on gastric mucosa injury with rikkunshito administration. In addition, rikkunshito in combination with an anti-emetic drug is effective against anorexia and vomiting that occur as adverse reactions to chemotherapy in patients with advanced breast cancer. However, the mechanism by which rikkunshito alleviates gastrointestinal disorders induced by anticancer agents remains unclear. It has recently been shown that rikkunshito ameliorates cisplatin-induced anorexia by mediating an increase in the circulating ghrelin concentration. Moreover, Fujitsuka et al. found that decreased contractions of the antrum and duodenum in rats treated with a selective serotonin reuptake inhibitor were reversed by rikkunshito via enhancement of the circulating ghrelin concentration. These findings show that rikkunshito may be useful for treatment of anorexia and may provide a new strategy for improvement of upper gastrointestinal dysfunction.
A Continuation Method for Weakly Kannan Maps
Authors: Ariza-Ruiz David , Jiménez-Melado Antonio
Published: January 2010

The first continuation method for contractive maps in the setting of a metric space was given by Granas. Later, Frigon extended Granas theorem to the class of weakly contractive maps, and recently Agarwal and O'Regan have given the corresponding result for a certain type of quasicontractions which includes maps of Kannan type. In this note we introduce the concept of weakly Kannan maps and give a fixed point theorem, and then a continuation method, for this class of maps.
Stability Analysis of Interconnected Fuzzy Systems Using the Fuzzy Lyapunov Method
Authors: Yeh Ken , Chen Cheng-Wu
Published: January 2010

The fuzzy Lyapunov method is investigated for use with a class of interconnected fuzzy systems. The interconnected fuzzy systems consist of J interconnected fuzzy subsystems, and the stability analysis is based on Lyapunov functions. Based on traditional Lyapunov stability theory, we further propose a fuzzy Lyapunov method for the stability analysis of interconnected fuzzy systems. The fuzzy Lyapunov function is defined in fuzzy blending quadratic Lyapunov functions. Some stability conditions are derived through the use of fuzzy Lyapunov functions to ensure that the interconnected fuzzy systems are asymptotically stable. Common solutions can be obtained by solving a set of linear matrix inequalities (LMIs) that are numerically feasible. Finally, simulations are performed in order to verify the effectiveness of the proposed stability conditions in this paper.
Depression among Centenarians and the Oldest Old: Contributions of Cognition and Personality
Authors: Margrett Jennifer , Martin Peter , Woodard John L. , Miller L. Stephen , MacDonald Maurice , Baenziger Joan , Siegler Ilene C. , Davey Adam , Poon Leonard
Published: January 2010

Background: An estimated 20% of adults over the age of 55 experience clinical mental disorders such as depression and anxiety. For older adults, mental health concerns are often undetected, concomitant with physical challenges, and ultimately go untreated. These realities have significant implications for older adults’ day-to-day functioning, particularly among the oldest old. Objective: The present study examined the ability of cognition and personality in explaining depression within a sample of octogenarians and centenarians. Methods: Participants were assessed during the most recent cross-sectional data collection of the Georgia Centenarian Study. The final eligible sample included 76 octogenarians (mean: 84.25 years, SD: 2.82; range: 81–90) and 158 centenarians and near centenarians (mean: 99.82 years, SD: 1.72; range: 98–109). Results: Hierarchical regression analyses were conducted to examine the relation between key variables and depressive symptoms in the two age groups. Blocks entered into the analyses included: demographics (i.e. age group, residential status, sex, and ethnicity) and functioning, memory and problem-solving ability, and personality (i.e. extraversion and neuroticism). Models differed for octogenarians and centenarians. Decreased problem-solving ability was related to greater depressive symptoms among octogenarians. For centenarians, institutional residence and increased neurotic tendencies were related to greater depressive symptoms. Conclusion: Study findings demonstrate the need to examine a variety of factors which influence mental health in later life and to consider the unique contexts and differential experiences of octogenarians and centenarians.
Distal and Proximal Resource Influences on Economic Dependency among the Oldest Old
Authors: MacDonald Maurice , Aneja Aradhana , Martin Peter , Margrett Jennifer , Poon Leonard W.
Published: January 2010

Background: As exceptional survivors, centenarians may have characteristics that reduce their dependency on family and community support systems despite the expectation that their extreme age creates a burden on those systems. The Georgia Centenarian Study obtained information about assistance for income, medical care, and caregiving of all types for a sample of centenarians and octogenarians. Previous studies have not established which characteristics may contribute to economic dependency among the oldest old. Objective: To identify distal and proximal resource influences on economic dependency, considering past lifestyle, proximal health, economic resources, personality, and coping behavior. Methods: Analysis sample sizes ranged from 109 to 138 octogenarians and centenarians. Blockwise multiple regressions predicted whether they received income assistance, number of medical care events, number of caregiving types, and total caregiving hours. Results: Past life style, gender, ethnicity, socioeconomic status, functional health, and coping were not related to economic dependency. With the exception of the number of types of care, centenarians were not more dependent than octogenarians. Cognitive ability had the strongest effects for medical care and caregiving services. ‘Extraversion’, ‘ideas’, ‘neuroticism’, and ‘competence’ personality factors had significant effects for caregiving types and total hours of care received. Conclusion: Monitoring and intervention to maintain cognitive ability are critical practices for autonomy and reduced economic dependency among the oldest old. Psychological resources are more important influences on social support than functional health and other proximal economic resources.
Social Resources and Longevity: Findings from the Georgia Centenarian Study
Authors: Randall G. Kevin , Martin Peter , McDonald Maurice , Poon Leonard W.
Published: January 2010

Background: As the proportion of adults aged 85 and older increases, investigations of resources essential for adapting to the challenges of aging are required. Objective: To comprehensively investigate the social resources of cognitively intact centenarians participating in the Georgia Centenarian Study and the association between these resources and residence status. Methods: Two widely used measures of social resources were investigated among participants living in private homes, personal care facilities, and nursing homes. Logistic regression was used to determine significant predictors of nursing home residence. Results: Differences in levels of social resources were found between centenarians and octogenarians, and among centenarians in different living situations. Analyses revealed differential findings between self- and proxy reports. Controlling for education, activities of daily living, and financial ability to meet needs, only one of the two social resources measures significantly reduced the odds of nursing home residence. Conclusion: The findings of this study add to the existing literature on one of the basic adaptive resources (social resources) for centenarians. Whether a more specific assessment of network contact is employed, or a more global assessment is used, differences in these constructs exist between centenarians and octogenarians, among centenarians in differing living conditions, and across types of informants. Researchers examining the different resources that may contribute to extraordinary longevity and positive adaptation may find it essential to differentiate between the oldest old and centenarians, and to account for differences based upon measure, reporter type, and centenarian residence status.
Synchronous Ventriculoscopic and Microsurgical Resection of Complex Craniopharyngiomas
Authors: Filis Andreas K. , Moon Karam , Cohen Alan R.
Published: January 2010

Background: Surgical resection of craniopharyngiomas may be challenging sometimes because of the size, location and tenacity. Simultaneous endoscopic and microsurgical resection is a novel way to approach such lesions. The aim of this report is to discuss the usefulness of combined endoscopic and microsurgical approaches in treating complex craniopharyngiomas along with a review of the literature. Methods: A child with hydrocephalus and a large suprasellar craniopharyngioma underwent synchronous endoscopic and microsurgical resection of the lesion. Results: Gross total resection of the tumor was achieved. There were no postoperative complications. Hydrocephalus was also treated successfully. Conclusions: Neuroendoscopy can complement microsurgery in approaching complex craniopharyngiomas particularly when these tumors are large and accompanied by hydrocephalus.
Mortality in First 5 Years in Infants With Functional Single Ventricle Born in Texas, 1996 to 2003
Authors: Fixler David E. , Nembhard Wendy N. , Salemi Jason L. , Ethen Mary K. , Canfield Mark A.
Published: January 2010

Background—

Infants with functional single ventricle have a high risk of death during the early years of life. Studies have reported improvement in postoperative survival, but they do not include preoperative deaths or those occurring before transfer. The purpose of this population-based study was to estimate 5-year survival in infants with functional single ventricle, to define factors associated with survival, and to estimate improvement in outcome.

Methods and Results—

Patients with hypoplastic left heart syndrome, pulmonary atresia intact ventricular septum, single ventricle, and tricuspid atresia born in 1996 to 2003 were identified from the Texas Birth Defects Registry and linked to state and national birth and death vital records. We examined the effects of defect type, birth era, birth weight, gestational age, maternal race/ethnicity, extracardiac anomalies, sex, and maternal age and education on survival. Five-year survival varied by defect type: hypoplastic left heart syndrome, 38.0% (95% confidence interval, 32.6 to 43.5); single ventricle, 56.1% (95% confidence interval, 49.9 to 61.7); pulmonary atresia intact ventricular septum, 55.7% (95% confidence interval, 45.8 to 64.4); and tricuspid atresia, 74.6% (95% confidence interval, 62.4 to 83.4). The presence of extracardiac defects increased the adjusted risk of death by 84%. Non-Hispanic blacks had an adjusted risk of death that was 41% higher than that for non-Hispanic whites, and Hispanics had a 26% higher risk. Patients born in 2001 to 2003 had a 47% lower risk than those born in 1996 to 2000.

Conclusions—

This population-based study demonstrates significant improvement in overall 5-year survival, particularly in cases of hypoplastic left heart syndrome and single ventricle. Additional studies are needed to determine the factors causing racial/ethnic and regional differences in outcome.
Longitudinal Tracking of Left Atrial Diameter Over the Adult Life Course: Clinical Correlates in the Community
Authors: McManus David D. , Xanthakis Vanessa , Sullivan Lisa M. , Zachariah Justin , Aragam Jayashri , Larson Martin G. , Benjamin Emelia J. , Vasan Ramachandran S.
Published: January 2010

Background—

Increased left atrial diameter (LAD) is associated with elevated risk of atrial fibrillation (AF) and cardiovascular disease. Information is limited regarding the short- or long-term correlates of LAD.

Methods and Results—

We evaluated clinical correlates of LAD for a 16-year period in 4403 Framingham Study participants (mean age, 45 years; 52% women; median observations/participant=3) using multilevel modeling. We related age, sex, body mass index (BMI), systolic and diastolic blood pressure (BP), diabetes, and antihypertensive treatment to LAD. Sex-specific growth curves for LAD were estimated for individuals with low, intermediate, and high risk factor burden. We also related risk factors to changes in LAD during a 4-year period in 3365 participants. Age, male sex (3.83 mm compared to women), greater BMI, higher systolic BP (0.24 mm per 10 mm Hg increment), and antihypertensive treatment (0.54 mm) were associated positively with LAD (
P
<0.001). Men had a greater increase in LAD with BMI than women (2.02 versus 1.77 mm in women, per 5-unit increment), and individuals receiving antihypertensive treatment experienced a greater increase in LAD with age (0.95 versus 0.63 mm per 10-year age increment) when compared with those not receiving antihypertensive treatment. Overall, greater risk factor burden was positively associated with LAD. These risk factors were also associated positively with 4-year change in LAD (
P
<0.001).

Conclusions—

Our longitudinal study of a large community-based sample identified higher BP and greater BMI as key modifiable correlates of LAD, suggesting that maintaining optimal levels of these risk factors through the life course may prevent atrial remodeling and AF.
Analysis of Ventricular Activation Using Surface Electrocardiography to Predict Left Ventricular Reverse Volumetric Remodeling During Cardiac Resynchronization Therapy
Authors: Sweeney Michael O. , van Bommel Rutger J. , Schalij Martin J. , Borleffs C. Jan Willem , Hellkamp Anne S. , Bax Jeroen J.
Published: January 2010

Background—

Cardiac resynchronization therapy for heart failure with left bundle branch block reduces left ventricular (LV) conduction delay, contraction asynchrony, and LV end-systolic volume (“reverse remodeling”). Up to one third of patients do not improve, and the electric requirements for reverse remodeling are unclear. We hypothesized that reverse remodeling is predicted by the left bundle branch block ventricular activation sequence, the paced activation sequence, and interactions between these 2 conditions.

Methods and Results—

Twelve-lead ECGs during left bundle branch block and cardiac resynchronization therapy were analyzed in 202 consecutive patients (New York Heart Association class III to IV heart failure, ejection fraction ≤35%) for predictors of reverse remodeling (≥10% reduction in end-systolic volume) at 6 months. Greater longest baseline LV activation time predicted increased odds of reverse remodeling (odds ratio [confidence interval]=1.30 [1.11, 1.52] per 10-ms increase), whereas higher QRS scores for LV scar predicted reduced reverse remodeling (odds ratio [confidence interval]=0.49 [0.27, 0.88] for each 1-point increase from 0 to 4; 0.92 [0.83, 1.01] for each 1-point increase >4). After cardiac resynchronization therapy, increasing R amplitudes in leads V
1
through V
2
(odds ratio [confidence interval]=2.76 [1.01, 7.51] for each 1× increase over [baseline R×4.5]) and left→right frontal axis shift (odds ratio [confidence interval]=2.00 [0.99, 4.02]), indicators of ventricular activation wavefront fusion, were positive predictors of reverse remodeling. Predicted probability of reverse remodeling ranged from <20% for patients with adverse predictors to 99% for those with positive predictors.

Conclusions—

Ventricular activation with the use of the ECG accurately predicts LV reverse remodeling during cardiac resynchronization therapy. Greater longest baseline LV activation time and smaller scar volume combined with wavefront fusion on the paced ECG, anticipate higher probability of reverse remodeling.
Individual/Neighborhood Social Factors and Blood Pressure in the RECORD Cohort Study
Authors: Chaix Basile , Bean Kathy , Leal Cinira , Thomas Frédérique , Havard Sabrina , Evans David , Jégo Bertrand , Pannier Bruno
Published: January 2010

Recent studies have started to suggest that, beyond effects of individual socioeconomic profiles, socioeconomic characteristics of residential neighborhoods are independently associated with blood pressure. However, mechanisms involved in these associations remain unknown. To distinguish between different mechanisms, we investigated whether specific risk factors of hypertension (physical inactivity, alcohol consumption, smoking, body mass index, waist circumference, and resting heart rate) intervene as mediators in the associations between individual or neighborhood socioeconomic characteristics and systolic blood pressure. We relied on data from the RECORD Cohort Study (Residential Environment and CORonary heart Disease) on 5941 participants recruited in 2007–2008, aged 30 to 79 years, residing in 1824 neighborhoods in the Paris metropolitan area. Systolic blood pressure increased independently and regularly with both decreasing individual education and decreasing residential neighborhood education. Body mass index/waist circumference and resting heart rate mediated an appreciable share of the associations between education and blood pressure and, adding validity to the finding, were the 2 most significant mediators for the effects of both individual education and neighborhood education. We found that 52% (95% CI: 25% to 79%) of the association between neighborhood education and blood pressure was mediated by body mass index/waist circumference and 20% (95% CI: 5% to 36%) by resting heart rate. Future research will have to clarify the exact mechanisms through which body weight and shape and resting heart rate intervene as mediators in the associations between individual/neighborhood education and blood pressure.
Spiral Arterial Remodeling Is Not Essential for Normal Blood Pressure Regulation in Pregnant Mice
Authors: Burke Suzanne D. , Barrette Valérie F. , Bianco Juares , Thorne Julie G. , Yamada Aureo T. , Pang Stephen C. , Adams Michael A. , Croy B. Anne
Published: January 2010

Maternal cardiovascular adaptations occur in normal pregnancy, systemically, and within the uterus. In humans, gestational control of blood pressure is clinically important. Transient structural remodeling of endometrial spiral arteries normally occurs in human and mouse pregnancies. In mice, this depends on uterine natural killer cell function. Using normal and immune-deficient mice, we asked whether spiral artery remodeling critically regulates gestational mean arterial pressure and/or placental growth. Radiotelemetric transmitters were implanted in females and hemodynamic profiles to a dietary salt challenge and to pregnancy were assessed. Implantation sites from noninstrumented females were used for histological morphometry. Both normal and immune-deficient mice had normal sensitivity to salt and showed similar 5-phase gestational patterns of mean arterial pressure correlating with stages of placental development, regardless of spiral artery modification. After implantation, mean arterial pressure declined during the preplacental phase to reach a midgestation nadir. With gestation day 9 opening of placental circulation, pressure rose, reaching baseline before parturition, whereas heart rate dropped. Heart rate stabilized before parturition. Placental sizes deviated during late gestation when growth stopped in normal mice but continued in immune-deficient mice. As an indication of the potential for abnormal hemodynamics, 2 pregnant females delivering dead offspring developed late gestational hypertension. This study characterizes a dynamic pattern of blood pressure over mouse pregnancy that parallels human gestation. Unexpectedly, these data reveal that spiral artery remodeling is not required for normal gestational control of blood pressure or for normal placental growth.
Chronic Angiotensin II Infusion Causes Differential Responses in Regional Sympathetic Nerve Activity in Rats
Authors: Yoshimoto Misa , Miki Kenju , Fink Gregory D. , King Andrew , Osborn John W.
Published: January 2010

Angiotensin II (AngII)–induced hypertension in experimental animals has been proposed to be attributed in part to activation of the sympathetic nervous system. This sympathetic activation appears to be accentuated in animals consuming a high-salt diet (AngII-salt hypertension). However, accurate quantification of sympathetic activity is difficult, and controversy remains. It is particularly important to ask which are the critical vascular beds targeted by increased sympathetic nerve activity (SNA) in AngII-salt hypertension. To address this issue, mean arterial pressure and renal SNA or lumbar SNA were continuously recorded during a 5-day control period, 11 days of AngII (150 ng/kg per minute, SC), and a 5-day recovery period in conscious rats on a high-salt (2% NaCl) diet. Although mean arterial pressure reached a new steady-state level of 30 to 35 mm Hg above control levels by the end of the AngII period, renal SNA decreased by 40% during the first 7 days of AngII and then returned toward control levels by day 10 of AngII. In contrast, lumbar SNA remained at control levels throughout the AngII period. In another experiment we measured hindlimb norepinephrine spillover in conscious rats on normal (0.4%) or high- (2.0%) salt diets before and during 14 days of AngII administration. AngII had no significant affect on hindlimb norepinephrine spillover in either group. We conclude that chronic AngII modulates renal and lumbar SNAs differentially in rats consuming a high-salt diet and that AngII-salt hypertension in the rat is not caused by increased SNA to the renal or hindlimb vascular beds.
Sympathetic Nonadrenergic Transmission Contributes to Autonomic Dysreflexia in Spinal Cord–Injured Individuals
Authors: Groothuis Jan T. , Rongen Gerard A. , Deinum Jaap , Pickkers Peter , Danser A. H. Jan , Geurts Alexander C.H. , Smits Paul , Hopman Maria T.E.
Published: January 2010

Autonomic dysreflexia is a hypertensive episode in spinal cord–injured individuals induced by exaggerated sympathetic activity and thought to be α-adrenergic mediated. α-Adrenoceptor antagonists have been a rational first choice; nevertheless, calcium channel blockers are primarily used in autonomic dysreflexia management. However, α-adrenoceptor blockade may leave a residual vasoconstrictor response to sympathetic nonadrenergic transmission unaffected. The aim was to assess the α-adrenergic contribution and, in addition, the role of supraspinal control to leg vasoconstriction during exaggerated sympathetic activity provoked by autonomic dysreflexia in spinal cord–injured individuals and by a cold pressure test in control individuals. Upper leg blood flow was measured using venous occlusion plethysmography during supine rest and during exaggerated sympathetic activity in 6 spinal cord–injured individuals and 7 able-bodied control individuals, without and with phentolamine (α-adrenoceptor antagonist) and nicardipine (calcium channel blocker) infusion into the right femoral artery. Leg vascular resistance was calculated. In spinal cord–injured individuals, phentolamine significantly reduced the leg vascular resistance increase during autonomic dysreflexia (8±5 versus 24±13 arbitrary units;
P
=0.04) in contrast to nicardipine (15±10 versus 24±13 arbitrary units;
P
=0.12). In controls, phentolamine completely abolished the leg vascular resistance increase during a cold pressure test (1±2 versus 18±14 arbitrary units;
P
=0.02). The norepinephrine increase during phentolamine infusion was larger (
P
=0.04) in control than in spinal cord–injured individuals. These results indicate that the leg vascular resistance increase during autonomic dysreflexia in spinal cord–injured individuals is not entirely α-adrenergic mediated and is partly explained by nonadrenergic transmission, which may, in healthy subjects, be suppressed by supraspinal control.
Valsartan Protects Pancreatic Islets and Adipose Tissue From the Inflammatory and Metabolic Consequences of a High-Fat Diet in Mice
Authors: Cole Banumathi K. , Keller Susanna R. , Wu Runpei , Carter Jeffrey D. , Nadler Jerry L. , Nunemaker Craig S.
Published: January 2010

Obesity, hypertension, cardiovascular disease, and inflammation are closely associated with the rising incidence of diabetes mellitus. One pharmacological target that may have significant potential to lower the risk of obesity-related diseases is the angiotensin type 1 receptor (AT1R). We examined the hypothesis that the AT1R blocker valsartan reduces the metabolic consequences and inflammatory effects of a high-fat (Western) diet in mice. C57BL/6J mice were treated by oral gavage with 10 mg/kg per day of valsartan or vehicle and placed on either a standard chow or Western diet for 12 weeks. Western diet-fed mice given valsartan had improved glucose tolerance, reduced fasting blood glucose levels, and reduced serum insulin levels compared with mice fed a Western diet alone. Valsartan treatment also blocked Western diet–induced increases in serum levels of the proinflammatory cytokines interferon-γ and monocyte chemotactic protein 1. In the pancreatic islets, valsartan enhanced mitochondrial function and prevented Western diet–induced decreases in glucose-stimulated insulin secretion. In adipose tissue, valsartan reduced Western diet–induced macrophage infiltration and expression of macrophage-derived monocyte chemotactic protein 1. In isolated adipocytes, valsartan treatment blocked or attenuated Western diet–induced changes in expression of several key inflammatory signals: interleukin 12p40, interleukin 12p35, tumor necrosis factor-α, interferon-γ, adiponectin, platelet 12-lipoxygenase, collagen 6, inducible NO synthase, and AT1R. Our findings indicate that AT1R blockade with valsartan attenuated several deleterious effects of the Western diet at the systemic and local levels in islets and adipose tissue. This study suggests that AT1R blockers provide additional therapeutic benefits in the metabolic syndrome and other obesity-related disorders beyond lowering blood pressure.
Receptor Activity-Modifying Protein 1 Increases Baroreflex Sensitivity and Attenuates Angiotensin-Induced Hypertension
Authors: Sabharwal Rasna , Zhang Zhongming , Lu Yongjun , Abboud Francois M. , Russo Andrew F. , Chapleau Mark W.
Published: January 2010

Calcitonin gene-related peptide (CGRP) is a powerful vasodilator that interacts with the autonomic nervous system. A subunit of the CGRP receptor complex, receptor activity-modifying protein 1 (RAMP1), is required for trafficking of the receptor to the cell surface and high-affinity binding to CGRP. We hypothesized that upregulation of RAMP1 would favorably enhance autonomic regulation and attenuate hypertension. Blood pressure, heart rate, and locomotor activity were measured by radiotelemetry in transgenic mice with ubiquitous expression of human RAMP1 (hRAMP1) and littermate controls. Compared with control mice, hRAMP1 mice exhibited similar mean arterial pressure, a lower mean heart rate, increased heart rate variability, reduced blood pressure variability, and increased baroreflex sensitivity (2.83±0.20 versus 1.49±0.10 ms/mm Hg in controls;
P
<0.05). In control mice, infusion of angiotensin II (Ang-II) increased mean arterial pressure from 118±2 mm Hg to 153±4 and 174±6 mm Hg after 7 and 14 days of infusion, respectively (
P
<0.05). In contrast, Ang-II hypertension was markedly attenuated in hRAMP1 mice with corresponding values of mean arterial pressure of 111±2, 119±2, and 132±3 mm Hg. Ang-II induced decreases in baroreflex sensitivity and heart rate variability, and increases in blood pressure variability observed in control mice were also abrogated or reversed in hRAMP1 mice (
P
<0.05). Moreover, during the Ang-II infusion, the pressor response to the CGRP receptor antagonist CGRP
8-37
was significantly greater (
P
<0.05) in hRAMP1 mice (+30±2 mm Hg) than in control mice (+19±2 mm Hg), confirming a significantly greater antihypertensive action of endogenous CGRP in hRAMP1 mice. We conclude that RAMP1 overexpression attenuates Ang-II-induced hypertension and induces a protective change in cardiovascular autonomic regulation.
Did Theophrastus Reject Aristotle’s Account of Place?
Authors: Morison Ben
Published: January 2010

It is commonly held that Theophrastus criticized or rejected Aristotle’s account of place. The evidence that scholars put forward for this view, from Simplicius’ commentary on Aristotle’s Physics, comes in two parts: (1) Simplicius reports some aporiai that Theophrastus found for Aristotle’s account; (2) Simplicius cites a passage of Theophrastus which is said to ‘bear witness’ to the theory of place which Simplicius himself adopts (that of his teacher Damascius) ‐ a theory which is utterly different from Aristotle’s. But the aporiai have relatively straightforward solutions, and we have no reason to suppose that Theophrastus didn’t avail himself of them (and some reason to think that he did). Moreover, the text which Simplicius cites as bearing witness to Damascius’ view on closer inspection does not seem to be inconsistent with Aristotle’s account of place or natural motion.
Plants producing pyrrolizidine alkaloids: sustainable tools for nematode management?
Authors: Boppré Michael , Thoden Tim
Published: January 2010

1,2-dehydropyrrolizidine ester alkaloids (pyrrolizidine alkaloids; PAs) are a class of secondary plant metabolites found in hundreds of plant species. In vitro, PAs are known to affect plant-parasitic nematodes. Thus, PA-producing plants might be used in nematode management. So far, however, Crotalaria is the only PA-producing plant that has been used for nematode control. Consequently, we reviewed the literature on other PA plants and their effects on nematodes. This included the analysis of in vitro experiments with PA plant extracts, host tests with PA plants, as well as experiments in which PA-producing plants were used as different types of soil amendments (mulch, in situ mulching, extracts). Our results clearly show that, in addition to Crotalaria, certain other PA-producing plant species have the potential to be used in sustainable nematode management. This is especially true for management of sedentary endoparasitic nematode species. Promising applications include the use of PA plant extracts and mulches, as well as the use of PA plants for in situ mulching.
Type specimens deposited at the University of California Riverside Nematode Collection
Authors: Mundo-Ocampo Manuel , Baldwin James
Published: January 2010

The University of California Riverside Nematode Collection (UCRNC) was founded by S.A. Sher in 1953. Today it includes ca 35 000 slides and nearly 180 000 mounted specimens of nematodes from around the world, soil Tylenchida being particularly strongly represented. In addition to material mounted on slides, the collection is a repository for vials of bulked collections, scanning electron micrographs and a supporting reprint collection. The collection of name-bearing types, with more than 3200 slides, is published herein.
Acrostichus puri n. sp. (Nematoda: Diplogastridae), a phoretic associate of Augochlora pura mosieri Cockerell (Hymenoptera: Halictidae)
Authors: Zeng Yongsan , Thomas W. Kelley , Kanzaki Natsumi , Center Barbara , Giblin-Davis Robin , Ye Weimin
Published: January 2010

Acrostichus puri n. sp., isolated from the body of a sweat bee, Augochlora pura mosieri, is described and figured. The new species is morphologically, molecularly and biologically very similar to A. halicti, i.e., these two species share a very complicated gubernaculum structure, distally hooked spicules with a triangular flap-like rostrum, stomatal polymorphism and synchronised associations with halcitid bees. The new species can be distinguished from A. halicti by its spicule morphology, distinctive squared manubrium and sharply bent (= ca 90° or L-shaped) distal tip vs an indistinctive rounded manubrium and a strongly recurved (= ca 180° or U-shaped) distal tip; gubernaculum with narrower, longer, anterior part and more complex posterior part than A. halicti, and tail of both sexes, with a long and filiform spike on the male or female tail vs a short spike (male) or conical tail (female). These two species also differ from each other by significant molecular sequence differences in SSU (2.0%), D2/D3 LSU (4.5%) and mtCOI (9.2%), and are reproductively incompatible in mating tests.
Diversity and distribution of nematodes associated with wild bees in Turkey
Authors: Keskin Nevin , Hazir Selcuk , Giblin-Davis Robin , Thomas W. Kelley , Hazir Canan , Ye Weimin , Scheuhl Erwin
Published: January 2010

The diversity and distribution of nematodes associated with soil-dwelling bees in Turkey were examined. A total of 9456 wild bees were collected and dissected to detect nematodes and 173 female and 22 male bees were positive for an overall association level of 2.1%. Halictus resurgens was the most commonly collected bee found with nematodes with 82 and 19 nematode-infested female and male bees, respectively. Sixty-four of the nematode isolates were recovered from the Black Sea region (32.8%), 59 from Central Anatolia (30.3%), 35 from the Mediterranean (17.9%), 24 from the Aegean (12.3%), six from Eastern Anatolia (3.1%) and seven from Southeast Anatolia (3.6%). In 3.9% of all bees of the family Halictidae (173/4417), nematodes were observed in the Dufour's gland, poison sac, oviduct, bursa copulatrix and abdominal cavity of dissected female bees and from the genital capsule of male bees. Only abdominal glands of 0.6% (21/3279) of female bees from the family Andrenidae were observed with nematodes. Nematodes were isolated from the genital capsule of one male bee from the family Melittidae. The poison sac was the organ where nematodes were most often observed but the highest number of nematodes occurred in the abdominal cavity. Most nematodes were in the dauer juvenile stage making identification difficult. Sequence analysis using LSU D2/D3 domains and a fragment of mitochondrial cytochrome oxidase I (mtCOI) allowed for putative identification of nematode isolates. Two or three species of Bursaphelenchus (B. anatolius, B. debrae, and potentially one or more cryptic species closest in morphology to B. anatolius) were isolated from six different halictid species (two genera; Halictus and Lasioglossum) from different geographical regions in Turkey. An additional four species of diplogastrid were recovered from the abdominal glands of andrenids; a new species of Koerneria from Andrena limata and a separate sister clade to Mononchoides composed of three other possible species from four Andrena species. An additional unknown species in the order Tylenchida (near Allantonematinae) was recovered from three species of Lasioglossum. No molecular data were obtained from three mermithid juveniles from two Andrena and one Halictus species because samples were lost in transit. The associations of most nematode isolates with bees of the families Halictidae and Andrenidae were hypothesised to be phoretic, whereas the tylenchid and mermithids were parasites.
Redescription of two Panamanian nematodes, Parasitodiplogaster citrinema Poinar & Herre, 1991 and P. popenema Poinar & Herre, 1991 (Nematoda: Diplogastrina)
Authors: Center Barbara , Giblin-Davis Robin , Herre E. Allen , Kanzaki Natsumi
Published: January 2010

Parasitodiplogaster citrinema and P. popenema were re-isolated from syconia of Ficus citrifolia and F. popenoei, respectively, from Barro Colorado Island, Panama, and are redescribed and figured herein. Both of these species were previously described as having a “well-developed stoma” and in the case of P. popenema with “stoma slightly longer than wide”. Re-examination of fresh material revealed that they share characteristic stomatal morphology, i.e., relatively wide and tube-like stomas with newly observed thorn-like stegostomatal teeth. This is distinctive from the other described Parasitodiplogaster species, which either have a relatively short and narrow stoma with protuberant, claw-like, teeth or a simple cylinder. In addition to the characters of the male papillae arrangement and spicule and gubernaculum morphology, these two species are distinguished from each other by newly-observed lip morphology characters, viz., P. citrinema has three small setae on the outer surface of each lip sector whereas P. popenema has smooth lips. Both P. citrinema and P. popenema appear typologically closest to P. sycophilon, which has a relatively wide and open stoma and seven pairs of male genital papillae, but were distinguished from P. sycophilon by the presence of stegostomatal teeth and the arrangement of the genital papillae.
Impact of Surface Flux Formulations and Geostrophic Forcing on Large-Eddy Simulations of Diurnal Atmospheric Boundary Layer Flow
Authors: Kumar Vijayant , Svensson Gunilla , Holtslag A. A. M. , Meneveau Charles , Parlange Marc B.
Published: January 2010

The impact of surface flux boundary conditions and geostrophic forcing on multiday evolution of flow in the atmospheric boundary layer (ABL) was assessed using large-eddy simulations (LES). The LES investigations included several combinations of surface boundary conditions (temperature and heat flux) and geostrophic forcing (constant, time varying, time and height varying). The setup was based on ABL characteristics observed during a selected period of the Cooperative Atmosphere–Surface Exchange Study—1999 (CASES-99) campaign. The LES cases driven by a constant geostrophic wind achieved the best agreement with the CASES-99 observations specifically in terms of daytime surface fluxes and daytime and nighttime profiles. However, the nighttime fluxes were significantly overestimated. The LES cases with the surface temperature boundary condition and driven by a time- and height-varying geostrophic forcing showed improved agreement with the observed nighttime fluxes, but there was less agreement with other observations (e.g., daytime profiles). In terms of the surface boundary condition, the LES cases driven by either surface temperature or heat fluxes produced similar trends in terms of the daytime profiles and comparisons with data from soundings. However, in reproducing the fluxes and nighttime profiles, the agreement was better with imposed temperature because of its ability to interact dynamically with the air temperature field. Therefore, it is concluded that surface temperature boundary condition is better suited for simulations of temporally evolving ABL flow as in the diurnal evolution of the ABL.
Partially Coherent Backscatter in Radar Observations of Precipitation
Authors: Jameson A. R. , Kostinski A. B.
Published: January 2010

Classical radar theory only considers incoherent backscatter from precipitation. Can precipitation generate coherent scatter as well? Until now, the accepted answer has been no, because hydrometeors are distributed sparsely in space (relative to radar wavelength) so that the continuum assumption used to explain coherent scatter in clear air and clouds does not hold.

In this work, a theory for a different mechanism is presented. The apparent existence of the proposed mechanism is then illustrated in both rain and snow. A new power spectrum Z( f ), the Fourier transform of the time series of the radar backscattered reflectivities, reveals statistically significant frequencies f of periodic components that cannot be ascribed to incoherent scatter. It is shown that removing those significant fs from Z( f ) at lower frequencies greatly reduces the temporal coherency. These lower frequencies, then, are associated with the increased temporal coherency. It is also shown that these fs are also directly linked to the Doppler spectral peaks through integer multiples of one-half the radar wavelength, characteristic of Bragg scatter. Thus, the enhanced temporal coherency is directly related to the presence of coherent scatter in agreement with theory.

Moreover, the normalized backscattered power spectrum Z( f ) permits the estimation of the fractional coherent power contribution to the total power, even for an incoherent radar. Analyses of approximately 26 000 one-second Z( f ) in both rain and snow reveal that the coherent scatter is pervasive in these data. These findings present a challenge to the usual assumption that the scatter of radar waves from precipitation is always incoherent and to interpretations of backscattered power based on this assumption.
Using Different Formulations of the Transformed Eulerian Mean Equations and Eliassen–Palm Diagnostics in General Circulation Models
Authors: Hardiman Steven C. , Andrews David G. , White Andy A. , Butchart Neal , Edmond Ian
Published: January 2010

Transformed Eulerian mean (TEM) equations and Eliassen–Palm (EP) flux diagnostics are presented for the general nonhydrostatic, fully compressible, deep atmosphere formulation of the primitive equations in spherical geometric coordinates. The TEM equations are applied to a general circulation model (GCM) based on these general primitive equations. It is demonstrated that a naive application in this model of the widely used approximations to the EP diagnostics, valid for the hydrostatic primitive equations using log-pressure as a vertical coordinate and presented, for example, by Andrews et al. in 1987 can lead to misleading features in these diagnostics. These features can be of the same order of magnitude as the diagnostics themselves throughout the winter stratosphere. Similar conclusions are found to hold for “downward control” calculations. The reasons are traced to the change of vertical coordinate from geometric height to log-pressure. Implications for the modeling community, including comparison of model output with that from reanalysis products available only on pressure surfaces, are discussed.
Modal and Nonmodal Growths of Symmetric Perturbations in Unbounded Domain
Authors: Xu Qin
Published: January 2010

Modal and nonmodal growths of nonhydrostatic symmetric perturbations in an unbounded domain are examined in comparison with their hydrostatic counterparts. It is shown that the modal growth rate is a function of a single internal parameter s, the slope of the cross-band wave pattern. The maximum nonmodal growth of total perturbation energy norm is produced, also as a function of s, by an optimal combination of one geostrophic neutral mode and two paired nongeostrophic growing and decaying (or propagating) modes in the unstable (or stable) region. The hydrostatic approximation inflates the maximum modal growth rate significantly (or boundlessly) as the basic-state Richardson number Ri is small (or → 0) and inflates the maximum nonmodal growth rate significantly (or boundlessly) as |s| is large (or → ∞).

Inside the unstable region, the maximum nonmodal growth scaled by the modal growth is a bounded increasing function of growth time τ but reduces to 1 at (Ri, s) = (¼, −2) where the three modes become orthogonal to each other. Outside the unstable region, the maximum nonmodal growth is a periodic function of τ and the maximum growth time τm is bounded between ¼ and ½ of the period of the paired propagating modes. The scaled maximum nonmodal growth reaches the global maximum at s = −Ri−1 ± Ri−1(1 − Ri)1/2 (the marginal-stability boundary) for any τ if Ri ≤ 1, or at s = −1 ± (1 − Ri−1)1/2 for τ = τm if Ri > 1. When the neutral mode is filtered, the nonmodal growth becomes nongeostrophic and smaller than its counterpart growth constructed by the three modes but still significantly larger than the modal growth in general. The scaled maximum nongeostrophic nonmodal growth reaches the global maximum at s = −Ri−1 ± Ri−1(1 − Ri)1/2 for any τ if Ri ≤ 1, or at s = −Ri−1/2 for τ = τm if Ri > 1. Normalized inner products between the modes are introduced to measure their nonorthogonality and interpret their constructed nonmodal growths physically.