bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental and numerical analysis of a sphere falling into a viscous fluid
Authors: Cruchaga Marcela , Löhner Rainald , Celentano Diego
Published: August 2011

The experimental and numerical analysis of spheres falling into viscous flows is considered. The physical model is built using a set of silicone and glass spheres falling into oil and water. The rigid‐body trajectory of the sphere and the free surface evolution are obtained from videos. The numerical results are obtained using two different finite element codes. The first code uses a fractional step approach with adaptive meshes and time‐step sizes whereas the second code uses a monolithic fully coupled fixed‐mesh technique. The results exhibit a good comparison between both numerical techniques and with the experiments. Copyright © 2011 John Wiley & Sons, Ltd.
The Role of External Sources of Information in Children's Evaluative Food Categories
Authors: Nguyen Simone P.
Published: August 2011

Evaluative food categories are value‐laden assessments, which reflect the healthfulness and palatability of foods (e.g. healthy/unhealthy, yummy/yucky). In a series of three studies, this research examines how 3‐ to 4‐year‐old children (N = 147) form evaluative food categories based on input from external sources of information. The results indicate that children prefer to ask a mom and teacher over a cartoon and child for information about the evaluative status of foods. However, children are cautious to accept information about healthy foods from all of the external sources compared with unhealthy, yummy and yucky foods. The results also indicate that providing information about the positive taste of healthy foods helps to encourage children to select healthy foods to eat. Taken together, these results have potential implications for children's health and nutrition education. Copyright © 2011 John Wiley & Sons, Ltd.
3,5,3′triiodo‐L‐thyronine induces SREBP‐1 expression by non‐genomic actions in human HEP G2 cells
Authors: Gnoni Gabriele V. , Rochira Alessio , Leone Antonella , Damiano Fabrizio , Marsigliante Santo , Siculella Luisa
Published: August 2011

Liver is an important target for thyroid hormone actions. T3 exerts its effects by two mechanisms: (i) Genomic actions consisting of T3 link to nuclear receptors that bind responsive elements in the promoter of target genes, (ii) non‐genomic actions including integrin αvb3 receptor‐mediated MAPK/ERK and PI3K/Akt/mTOR‐C1 activation. SREBP‐1a, SREBP‐1c, and SREBP‐2 are transcription factors involved in the regulation of lipogenic genes. We show in Hep G2 cells that T3 determined a dose‐ and time‐dependent increase in the level of the precursor form of SREBP‐1 without affecting SREBP‐1 mRNA abundance. T3 also induced phosphorylation of ERK1/2, Akt and of mTOR‐C1 target S6K‐P70, and the cytosol‐to‐membrane translocation of PKC‐α. Modulation of SREBP‐1 protein level by T3 was dependent on MAPK/ERK, PI3K/Akt/mTOR‐C1 pathway activation since the MEK inhibitor PD98059 or the PI3K inhibitor LY294002 abolished the stimulatory effect of T3. Conversely, the effect of T3 on SREBP‐1 level was enhanced by using rapamycin, mTOR‐C1 inhibitor. These data suggest a negative control of mTOR‐C1 target S6K‐P70 on PI3K/Akt pathway. The effect of T3 on SREBP‐1 content increased also by using PKC inhibitors. These inhibitors increased the action of T3 on Akt phosphorylation suggesting that conventional PKCs may work as negative regulators of the T3‐dependent SREBP‐1 increase. T3 effects were partially abrogated by tetrac, an inhibitor of the T3‐αvβ3 receptor interaction and partially evoked by T3 analog T3–agarose. These findings support a model in which T3 activates intracellular signaling pathways which may be involved in the increment of SREBP‐1 level through an IRES‐mediated translation mechanism. J. Cell. Physiol. 227: 2388–2397, 2012. © 2011 Wiley Periodicals, Inc.
Effects of environmental perturbations during postnatal development on the phenotypic integration of the skull
Authors: Gonzalez Paula Natalia , Oyhenart Evelia Edith , Hallgrímsson Benedikt
Published: August 2011

Integration and modularity are fundamental determinants of how natural selection effects evolutionary change in complex multivariate traits. Interest in the study of the specific developmental basis of integration through experimental approaches is fairly recent and it has mainly focused on its genetic determinants. In this study, we present evidence that postnatal environmental perturbations can modify the covariance structure by influencing the variance of some developmental processes relative to the variances of other processes that contribute to such structure. We analyzed the effects of the reduction of nutrient supply in different ontogenetic stages (i.e. before and after weaning, and from birth to adulthood) in Rattus norvegicus. Our results show that this environmental perturbation alters the phenotypic variation/covariation structure of the principal modules of the skull (base, vault, and face). The covariance matrices of different treatment groups exhibit low correlations and are significantly different, indicating that the treatments influence covariance structure. Postnatal nutrient restriction also increases the variance of somatic growth. This increased variance drives an increase in overall integration of cranial morphology through the correlated allometric effects of size variation. The extent of this increase in integration depends on the time and duration of the nutritional restriction. These results support the conclusion that environmental perturbations can influence integration and thus covariance structure via developmental plasticity. J. Exp. Zool. (Mol. Dev. Evol.) 316:547–561, 2011. © 2011 Wiley Periodicals, Inc.
Regulation of P‐glycoprotein by human immunodeficiency virus‐1 in primary cultures of human fetal astrocytes
Authors: Ashraf Tamima , Ronaldson Patrick T. , Persidsky Yuri , Bendayan Reina
Published: August 2011

P‐glycoprotein (P‐gp), a drug efflux pump, is known to alter the bioavailability of antiretroviral drugs at several sites, including the brain. We have previously shown that human immunodeficiency virus‐1 (HIV‐1) glycoprotein 120 (gp120) induces proinflammatory cytokine secretion and decreases P‐gp functional expression in rat astrocytes, a cellular reservoir of HIV‐1. However, whether P‐gp is regulated in a similar way in human astrocytes is unknown. This study investigates the regulation of P‐gp in an in vitro model of gp120‐triggered human fetal astrocytes (HFAs). In this system, elevated levels of interleukin‐6 (IL‐6), IL‐1β, and tumor necrosis factor‐α were detected in culture supernatants. Pretreatment with CCR5 neutralizing antibody attenuated cytokine secretion, suggesting that gp120‐CCR5 interaction mediated cytokine production. Treatment with gp120 (R5‐tropic) resulted in reduced P‐gp expression (64%) and function as determined by increased (1.6‐fold) cellular accumulation of [3H]digoxin, a P‐gp substrate. Exposure to R5 or R5/X4‐tropic viral isolates led to a downregulation in P‐gp expression (75% or 90%, respectively), and treatment with IL‐6 also showed lower P‐gp expression (50%). Moreover, IL‐6 neutralizing antibody blocked gp120‐mediated P‐gp downregulation, suggesting that IL‐6 is a key modulator of P‐gp. Gp120‐ or IL‐6‐mediated downregulation of P‐gp was attenuated by SN50 (a nuclear factor‐κB [NF‐κB] inhibitor), suggesting involvement of NF‐κB signaling in P‐gp regulation. Our results suggest that, similarly to the case with rodent astrocytes, pathophysiological stressors associated with brain HIV‐1 infection have a downregulatory effect on P‐gp functional expression in human astrocytes, which may ultimately result in altered antiretroviral drug accumulation within brain parenchyma. © 2011 Wiley‐Liss, Inc.
The new indirubin derivative inhibitors of glycogen synthase kinase‐3, 6‐BIDECO and 6‐BIMYEO, prevent tau phosphorylation and apoptosis induced by the inhibition of protein phosphatase‐2A by okadaic acid in cultured neurons
Authors: Martin Ludovic , Magnaudeix Amandine , Wilson Cornelia M. , Yardin Catherine , Terro Faraj
Published: August 2011

Alterations in glycogen synthase kinase‐3β (GSK3β) and protein phosphatase‐2A (PP2A) have been proposed to be involved in the abnormal tau phosphorylation and aggregation linked to Alzheimer's disease (AD). Interconnections between GSK3β and PP2A signaling pathways are well established. Targeting tau kinases was proposed to represent a therapeutic strategy for AD. However, which tau kinases should be blocked and to what extent, keeping in mind that kinases have physiological roles? Because most kinase inhibitors are relatively specific and many of them interfere with the cell cycle, it is necessary to develop more specific tau kinase inhibitors devoid of cell toxicity. Here, we used the PP2A inhibition by okadaic acid (OKA) in primary cultured cortical neurons as an in vitro model of increased tau phosphorylation and apoptosis. We tested the effects of two newly characterized indirubin derivative inhibitors of GSK3, 6‐BIDECO (6‐bromoindirubin‐3′‐[O‐(N,N‐diethylcarbamyl)‐oxime] and 6‐BIMYEO (6‐bromoindirubin‐3′‐[O‐(2‐morpholin‐1‐ylethyl)‐oxime] hydrochloride) on OKA‐induced tau phosphorylation and neuronal apoptosis. Both compounds exhibit higher selectivity toward GSK3 compared with other tau kinases (for 6‐BIDECO, IC50 is 0.03 μM for GSK3, >10 μM for CDK1, and 10 μM for CDK5; for 6‐BIMYEO, IC50 is 0.11 μM for GSK3, 1.8 μM for CDK1, and 0.9 μM for CDK5). We show that 6‐BIDECO and 6‐BIMYEO used at micromolar concentrations are not neurotoxic and potently reversed tau phosphorylation and apoptosis induced by OKA. The neuroprotection by these compounds should be further validated in animal models of AD. © 2011 Wiley‐Liss, Inc.
A crystallization conditions study of the Ti‐doped barium hexaferrite powders synthesized with the glass crystallization technique for microwave applications
Authors: Quiroz P. , Halbedel B.
Published: August 2011

For microwave applications Titanium doped M‐type hexagonal ferrites have been synthesized by means of glass crystallization technique varying the crystallization parameters and the melt doping concentrations. The chosen melt dopings were x = 5.4 and 7.2 mole‐% TiO2 with the following basic composition (mole‐%): 40 BaO + 33 B2O3 + (27‐x) Fe2O3 + x TiO2. We have studied the dependencies between the magnetic properties, the valence of the iron ions in the glasses and the powders, the formation of new dielectric phases and the microwave absorption. After the Ti4+ ions substitutions, the magnetocrystalline anisotropy changed, this effect was observed in the static magnetic properties (JHC and MS) measured using a vibration sample magnetometer. Furthermore the Ti4+ ions preferably occupy mainly the 2a as well as slightly the 2b sites in the lattice of the barium hexaferrite, which are studied using Mössbauer spectroscopy. Besides, the X‐ray diffraction studies proved that the formation of the ferrimagnetic (BaFe12‐xTixO12) and dielectric (BaTi6O13) phases are dependent on the crystallization parameters. The controlled influencing of lattice sites occupation and of the Fe2+ content in the ferrimagnetic phase as well as the controlled formation of the dielectric phase rate during the annealing are possibilities to optimize the microwave absorption of Ti‐doped barium hexaferrite powders synthesized by glass crystallization technique.
Evaluation of drug efflux transporter liabilities of darifenacin in cell culture models of the blood–brain and blood–ocular barriers
Authors: Miller Donald W. , Hinton Martha , Chen Fang
Published: August 2011

Aims

The objective of the present study was to evaluate drug efflux transporter interactions of darifenacin and examine the impact of such transporter interactions on darifenacin permeability in an in vitro model of the blood–brain barrier (BBB) and blood–ocular barrier (BOB).

Methods

Cell membranes expressing human P‐glycoprotein (P‐gp), multidrug resistance‐associated protein (MRP), and breast cancer resistance protein (BCRP) were examined for ATPase activity following darifenacin exposure (0–10 µM). Primary cultured bovine brain microvessel endothelial cells (BBMEC) and P‐gp transfected Manin–Darby canine kidney epithelial cells (MDCKMDR1) were used to examine darifenacin permeability and drug efflux transporter responses.

Results

Concentration‐dependent increases in ATPase activity was observed in P‐gp membranes following darifenacin exposure. Both MRP and BCRP membrane preparations were unresponsive to darifenacin. Studies in both BBMEC and MDCKMDR1 monolayers confirmed a P‐gp interaction for darifenacin and significantly greater efflux (basolateral to apical) permeability for darifenacin that was reduced by the P‐gp inhibitor, elacridar.

Conclusions

Darifenacin is a substrate for the P‐gp drug efflux transporter present in both BBB and BOB. The P‐gp drug efflux transporter liabilities of darifenacin may limit its penetration into brain and ocular tissue thereby reducing side effect potential. Neurourol. Urodynam. Neurourol. Urodynam. 30: 1633–1638, 2011. © 2011 Wiley Periodicals, Inc.
Botulinum toxin outcomes for idiopathic overactive bladder stratified by indication: Lack of anticholinergic efficacy versus intolerability
Authors: Makovey Iryna , Davis Tanya , Guralnick Michael L. , O'Connor R. Corey
Published: August 2011

Aims

To determine if the outcomes of intradetrusor botulinum toxin A (BTX‐A) injections for the management of refractory overactive bladder (OAB) symptoms are different if performed due to lack of anticholinergic efficacy versus medication intolerability.

Methods

Retrospective chart review was performed on all patients undergoing intradetrusor BTX‐A (BOTOX®, Allergan Inc., Irvine, CA) injections from 2004 to 2010 for the management of refractory idiopathic OAB with or without urge incontinence. All patients failed anticholinergic medications due to either lack of efficacy or intolerable side effects. Patient outcomes following BTX‐A injections (150–200 units) were compared based on the primary reason for discontinuing anticholinergic medications (lack of efficacy vs. intolerability). Successful BTX‐A injections were defined as those producing symptomatic OAB improvement warranting future repeat injections upon return of symptoms.

Results

A total of 85 patients were included in the study. Overall, 58/85 (68%) reported symptomatic improvement following BTX‐A injections. Successful outcomes were reported in 34/57 (60%) patients treated secondary to lack of anticholinergic efficacy versus 24/28 (86%) due to intolerable side effects (P = 0.02).

Conclusions

BTX‐A injections are more successful in patients with anticholinergic intolerability as compared to patients with poor medication efficacy (86% vs. 60%, P = 0.02). Neurourol. Urodynam. Neurourol. Urodynam. 30: 1538–1540, 2011. © 2011 Wiley Periodicals, Inc.
Hospitalised ischaemic cerebrovascular accident and risk factors in a primary care database
Authors: Martín‐Merino Elisa , Ruigomez Ana , Johansson Saga , García‐Rodríguez Luis‐Alberto
Published: August 2011

Purpose

Ischaemic cerebrovascular accident (ICVA) is a common cause of morbidity and mortality. Identification of risk factors can reduce its incidence. We aim to estimate the incidence rate (IR) of hospitalised ICVA in the general population by sex and quantify its risk associated with several factors.

Methods

We followed up 907 001 individuals aged 40–84 years during a mean of 3.63 years to ascertain the first episode of hospitalised ICVA between 2000 and 2004 using a UK primary care database. We evaluated the risk factors for ICVA through unconditional logistic regression (OR) with a nested case–control analysis, using 2953 incident cases and 10 000 random controls frequency‐matched by age, sex and year.

Results

The IR of hospitalised ICVA was 1.94 (95%CI: 1.87–2.01) per 1000 person‐years in men and 1.59 (95%CI: 1.53–1.65) in women. The IR ratio adjusted by age was 1.35 (95%CI: 1.28–1.43). Major risk factors for the first ICVA were atrial fibrillation (AF) (OR of 1.96 (95%CI: 1.59–2.42) for men and 3.54 (95%CI: 2.85–4.39) for women), smoking, epilepsy and hypertension. AF patients on anticoagulant therapy presented a reduced risk of ICVA (OR: 0.39; 95%CI: 0.27–0.56) in both sexes. Hypertensive women that discontinued the treatment had an increased risk (OR: 2.53; 95%CI: 1.63–3.91).

Conclusions

Men had higher incidence of hospitalised ICVA than women. AF was the major risk factor for ICVA (more in women than men), followed by smoking. Among AF patients, those under anticoagulant therapy showed a significant reduced risk of first ICVA. Antihypertensive drug discontinuation increased the risk of ICVA among women. Copyright © 2011 John Wiley & Sons, Ltd.
Optimal response‐adaptive randomized designs for multi‐armed survival trials
Authors: Sverdlov Oleksandr , Tymofyeyev Yevgen , Wong Weng Kee
Published: August 2011

We considered design issues for multiple treatment arms in survival intervention trials and used optimal design theory to allocate patients adaptively in such trials. We proposed three types of optimal designs: one ensures that we have the most precise estimates of the treatment effects, another guarantees that we have the minimal sample size subject to user‐specified allocation ratio assignments among treatment arms, and the third ensures that the design has minimal total hazard for the cohort. The latter two types of optimal designs are also subject to user‐specified power constraints for testing contrasts among treatment effects. The operating characteristics of these optimal designs along with balanced designs are compared theoretically and by simulation, including their robustness properties with respect to model misspecifications. Our results show that the proposed optimal designs are frequently unbalanced and that they are generally more efficient and more ethical than the popular balanced designs. We also apply our response‐adaptive allocation strategy to redesign a three‐arm head and neck cancer trial and make comparisons. Copyright © 2011 John Wiley & Sons, Ltd.
Composite Truss Bridges: new trends, design and research
Authors: Reis António , Oliveira Pedro José J.
Published: August 2011

Developments and new trends in composite truss bridges are reviewed, and recent designs are presented for road and railway bridges. The structural scheme may range from a continuous truss girder to a cable‐stayed bridge with a double deck for both road and rail traffic.

Composite decks with 3D tubular triangular trusses for road bridges are discussed; design issues are outlined and some results for the elastoplastic redistribution of internal forces at ULS, based on recent numerical and experimental research studies, are presented.

Recent designs of skew semi‐through composite trusses, for High Speed Railway, are reported in what concerns the dynamic behaviour under traffic loading and the stability of the compressed chord. The Base Case Design of a cable‐stayed bridge, 540 m long main span, with a double composite truss deck, for the new railroad crossing of the Tagus River in Lisbon, is discussed.
Effectiveness of Pre‐counseling Genetic Education Workshops at a Large Urban Community Health Center Serving Low‐Income Chinese American Women
Authors: Sim Shao‐Chee , Zhou Xiaojie Diana , Hom Laureen D. , Chen Christine , Sze Rebecca
Published: August 2011

Chinese American pregnant women and women of childbearing age face economic, cultural and linguistic barriers in accessing mainstream health care services. The Charles B. Wang Community Health Center developed a culturally and linguistically competent genetic education workshop for high‐risk Chinese American prenatal patients. Patients referred for genetic counseling for thalassemia, abnormal triple screen results, and/or advanced maternal age were recruited to participate in the workshop. The workshop provided basic “genetic 101” education, focusing on topics that were directly relevant to the patients’ reasons for referral. The effectiveness of the workshop was measured using a quasi‐experimental design with pre‐post surveys administered to intervention and control group participants. The evaluation also included a genetic counselor assessment and a pilot study of genetic counseling appointment length. Overall, workshop participants showed significant increases in knowledge, positive attitude and self‐efficacy regarding genetic services as compared to their control group counterparts. The pilot appointment length study data revealed that the workshop reduced the length of the genetic counseling appointment time by 40%. These positive findings suggest that it would be worthwhile to replicate the genetic education workshop at other health agencies serving Chinese‐speaking populations and that further evaluation research should be conducted.
Investigation of the Stability of Quaternary Ammonium Methyl Carbonates
Authors: Weisshaar Duane E. , Earl Gary W. , Amolins Michael W. , Mickalowski Kyle L. , Norberg Justin G. , Rekken Brian D. , Burgess Angela M. , Kaemingk Bethany D. , Behrens Katherine C.
Published: August 2011

Quaternary ammonium compounds are used commercially for a variety of applications and some are of interest as ionic liquids. For many years dimethyl carbonate has been touted as a green reagent, including its use for methylation (quaternization) of tertiary amines. In addition, substitution of the methyl carbonate by other anions can be efficiently and cleanly accomplished by reaction with the corresponding acid. How stable are these methyl carbonate quaternary compounds? High field 13C NMR shows that in the presence of water, the methyl carbonate is converted to bicarbonate. Headspace GCMS indicates that the alkylammonium methyl carbonate salts are stable below 170–180 °C while the bicarbonate salts are stable to only about 140 °C. Thermal decomposition occurs by decarboxylation and by dealkylation.
Effects of Multiple Endorsements and Consumer–Celebrity Attachment on Attitude and Purchase Intention
Authors: Ilicic Jasmina , Webster Cynthia M.
Published: August 2011

This study examines consumer–celebrity attachment within multiple endorsement situations. A 2 × 2 factorial design manipulates attachment strength to the celebrity and endorsement situation while controlling for celebrity attractiveness, familiarity and match-up. Results show strong attachment to a celebrity encourages positive attitude towards the advertisement and brand regardless of the number of endorsements. A significant interaction effect is found for purchase intention, suggesting that both attachment and the number of endorsements influence likelihood of purchase. When consumers are more attached to a celebrity and view that celebrity endorsing multiple brands, this negatively impacts their purchase intention. Yet, when consumers have a weak attachment, their purchase intention is increased with multiple endorsements.
How Salmonella oxidises H2 under aerobic conditions
Authors: Parkin Alison , Bowman Lisa , Roessler Maxie M. , Davies Rosalind A. , Palmer Tracy , Armstrong Fraser A. , Sargent Frank
Published: August 2011

Salmonella enterica serovar Typhimurium is a Gram negative bacterial pathogen and a common cause of food‐borne illness. Molecular hydrogen has been shown to be a key respiratory electron donor during infection and H2 oxidation can be catalysed by three genetically‐distinct [NiFe] hydrogenases. Of these, hydrogenases‐1 (Hyd‐1) and Hyd‐2 have well‐characterised homologues in Escherichia coli. The third, designated Hyd‐5 here, is peculiar to Salmonella and is expressed under aerobic conditions. In this work, Salmonella was genetically modified to enable the isolation and characterisation of Hyd‐5. Electrochemical analysis established that Hyd‐5 is a H2‐oxidising enzyme that functions in very low levels of H2 and sustains this activity in high levels of O2. In addition, electron paramagnetic resonance spectroscopy of the Hyd‐5 isoenzyme reveals a complex paramagnetic FeS signal at high potentials which is comparable to that observed for other O2‐tolerant respiratory [NiFe] hydrogenases. Taken altogether, Hyd‐5 can be classified as an O2‐tolerant hydrogenase that confers upon Salmonella the ability to use H2 as an electron donor in aerobic respiration.
Early physical exercise and seizure susceptibility later in life
Authors: Gomes da Silva Sérgio , de Almeida Alexandre Aparecido , Silva Araújo Bruno Henrique , Scorza Fulvio Alexandre , Cavalheiro Esper Abrão , Arida Ricardo Mario
Published: August 2011

We conducted a study to examine whether physical exercise undertaken during the period of postnatal brain development could modify seizure susceptibility later in life. Male Wistar rats aged 21 postnatal days (P21) were divided into two groups: exercise and control. Animals in the exercise group were submitted to daily exercise on the treadmill between P21 and P60. Running time and speed gradually increased over this period, reaching a maximum of 18 m/min for 60 min. After the final exercise session (P60), animals from exercise group were maintained non‐trained for 90 days. This “period without stimulus” was used to observe the influence of early physical exercise on susceptibility to seizures induced by the pilocarpine model of epilepsy at P150. The results showed that the exercise program undertaken during the period of postnatal brain development delayed the onset and reduced the intensity of pilocarpine‐induced motor symptoms in midlife rats. These findings suggest that early exercise interferes positively in the later ictogenesis process, and support the hypothesis that physical activity in early life may build a neural reserve against brain disorders.
Parotid Salivary Duct Sialocele Associated with Glandular Duct Stenosis in a Cat
Authors: Vallefuoco Rosario , Jardel Nicolas , El Mrini Meryem , Stambouli Fouzia , Cordonnier Nathalie
Published: August 2011

Feline parotid salivary duct sialocele is an uncommon disorder that has been previously reported in association with traumatic rupture of the duct in only two cats. Both cases were successfully treated by proximal duct ligation. We describe the successful surgical treatment of a parotid duct sialocele, secondary to spontaneous salivary duct stenosis, in an adult domestic shorthair cat. The cat was referred for assessment of a recurrent fluid-filled swelling on the left side of the face. Cytology of the aspirated fluid was consistent with serous saliva. The anatomical localisation of the lesion and the nature of the fluid were indicative of parotid gland/duct involvement. Retrograde sialography by parotid duct cannulation was unsuccessful because the left parotid duct opening was stenosed and obstructed by scar tissue. Surgical exploration revealed a parotid salivary duct sialocele, which was completely removed along with the parotid gland without complications.
Increases in mitochondrial biogenesis impair carcinogenesis at multiple levels
Authors: Wang Xiao , Moraes Carlos T.
Published: August 2011

Although mitochondrial respiration is decreased in most cancer cells, the role of this decrease in carcinogenesis and cancer progression is still unclear. To better understand this phenomenon, instead of further inhibiting mitochondrial function, we induced mitochondrial biogenesis in transformed cells by activating the peroxisome proliferator‐activated receptors (PPARs)/peroxisome proliferator‐activated receptor gamma co‐activator 1α (PGC‐1α) pathways. This was achieved by treating the cells with bezafibrate, a PPARs panagonist that also enhances PGC‐1α expression. We confirmed that bezafibrate treatment led to increased mitochondrial proteins and enzyme functions. We found that cells with increased mitochondrial biogenesis had decreased growth rates in glucose‐containing medium. In addition, they became less invasive, which was directly linked to the reduced lactate levels. Surprisingly, even though bezafibrate‐treated cells had higher levels of mitochondrial markers, total respiration was not significantly altered. However, respiratory coupling, and ATP levels were. Our data show that by increasing the efficiency of the mitochondrial oxidative phosphorylation system, cancer progression is hampered by decreases in cell proliferation and invasiveness.
Hip Strength and Knee Pain in High School Runners: A Prospective Study
Authors: Finnoff Jonathan T. , Hall Mederic M. , Kyle Kelli , Krause David A. , Lai Jim , Smith Jay
Published: August 2011

Objective

To determine whether pre‐injury hip muscle weakness is associated with the development of patellofemoral pain (PFP) in high school running athletes.

Design

Prospective cohort study.

Setting

Academic institution sports medicine center.

Participants

High school running athletes.

Methods

Baseline hip strength of high school running athletes was assessed at the beginning of the running season. Strength testing was repeated in athletes who developed PFP. Peak hip muscle strengths and strength ratios were compared between the injured and non‐injured groups.

Results

Six injuries occurred in 5 of the 98 subjects who completed the study. The baseline hip external‐to‐internal strength ratio was lower in injured than in uninjured subjects (P = .008). In the injured group, hip abduction and external rotation strengths decreased from pre‐injury to post‐injury (P = .002 and P = .01, respectively). Logistic regression analysis demonstrated that a greater baseline hip abduction strength (odds ratio = 5.35, 95% confidence interval [CI] 1.46‐19.53; P < .01) and abduction‐to‐adduction strength ratio increased the risk of injury (odds ratio = 14.14, 95% CI 0.90‐221.06; P = .05), and a greater pre‐injury hip external‐to‐internal rotation strength ratio decreased the risk of injury (odds ratio < 0.01, 95% CI ≤ .01, 0.44; P = .02).

Conclusions

The findings of the current study suggest that stronger pre‐injury hip abductors (particularly in relation to their hip adductors) and weaker pre‐injury hip external rotators (particularly in relation to their hip internal rotators) are associated with the development of PFP. In addition, persons in whom PFP develops appear to lose hip abduction and external rotation strength when compared with their pre‐injury strength. Finally, a higher hip external‐to‐internal rotation strength ratio may protect against the development of PFP.
Hegemonic political parties in post-Soviet Eurasia: Towards party-based authoritarianism?
Authors: Bader Max
Published: August 2011

Hegemonic parties in authoritarian regimes can fulfill important purposes for those regimes and thereby contribute to their survival. Along with the consolidation of authoritarian regimes, hegemonic political parties have emerged in some post-Soviet states, raising questions about the role that these parties play in the survival of the regimes. This article asks which of the purposes that are frequently ascribed to ruling authoritarian parties are fulfilled by United Russia, the Yeni Azerbaijan Party, and Nur Otan of Kazakhstan, the hegemonic parties of the three strongest consolidated authoritarian regimes with a hegemonic party in the former Soviet Union. It is argued that despite the increasing prominence of the hegemonic parties, full-fledged party-based authoritarianism has not yet been established in Russia, Azerbaijan, and Kazakhstan.
Lessons from the Mental Health Act Commission for England and Wales: The Limitations of Legalism-Plus-Safeguards
Authors: PILGRIM DAVID
Published: August 2011

In 2009, the Mental Health Act Commission for England and Wales was closed down and its functions subsumed in separate organisations in the two countries. Its final biennial report, issued that year, focused on coercion and consent. This article uses some aspects of the report to discuss the implications of lawful psychiatric coercion being predicted by social group membership (correlated with race, age and gender). The work of the Commission furnished useful information in this regard, but its framework for data collection could not, and so did not, illuminate a more established picture of the class gradient in mental health problems. With the latter literature in mind, material adversity may explain the racial patterning of psychiatric populations coercively detained. However, normative aspects of risk-taking in the community and in hospital may better predict the findings on age and gender. The article concludes by querying the ameliorative impact of government appointed ‘visitorial’ bodies. Legalism-plus-safeguards is a questionable basis for meaningfully bringing discriminatory powers to book, or for reversing the differential impact of pathogenic social forces.
Cognitive mechanism of writing to dictation of logographic characters
Authors: HAN ZAIZHU , SONG LUPING , BI YANCHAO
Published: August 2011

The cognitive mechanisms for writing to dictation of Chinese syllables by healthy adults were investigated using large-sample multiple regression analyses. In the experiment, subjects wrote down a corresponding character upon hearing a syllable. We mainly examined the effects of three types of attributes (i.e., lexical, semantic, and phonology to orthography conversion [POC] ones) in predicting the production probability of specific characters out of the homophone families for target syllables. We observed significant effects for all three types of attributes, as well as interactions between POC and the lexical attributes, and between POC and the semantic attributes. We further found that the semantic effects vanished for the writing stimuli without homophones. A feedback procedure (i.e., phonetic radical transparency) was also observed to influence Chinese writing performances. Our results support the hypothesis that the extent of semantic involvement in writing (spelling) to dictation is influenced by the effectiveness of POC procedure in a certain language and/or word set. The existence of an interaction between the lexical semantic route and the POC route in writing is further consolidated.
Lott's Bricks, The Arts and Crafts movement and Arnold Mitchell
Authors: Vale Brenda , Vale Robert
Published: August 2011

Perhaps unexpectedly, architects are seldom talked about in terms of the building toys they once played with or what they constructed with them. Exceptions are Witold Rybczynski and Frank Lloyd Wright. The former describes John Ruskin mastering the laws of building for load-bearing towers and arches by the time he was seven or eight (around 1825) because of playing with wooden building blocks (introduced at the end of the 1700s). However, he also describes himself playing with Bayko. This was a Bakelite building set from the 1930s [1], probably modelled on Mobaco, a cardboard and wood Dutch construction toy [2]. Both of these toys are pre-dated by an 1887 English toy for house construction, the walls of which were made from wooden blocks threaded on to vertical wires. Rybczynski also describes watching his father and uncle build a real garden shed using concrete panels slipped between reinforcing bars, like the method used by the plastic toy but life-size.
Two‐component mixtures of normal, gamma, and Gumbel distributions for hydrological applications
Authors: Evin G. , Merleau J. , Perreault L.
Published: August 2011

Whether mixtures of distributions are employed as a flexible modeling device to estimate densities or are used to model data thought to arise from several populations, they provide an efficient tool to approximate a distribution. Indeed, mixtures of distributions can model multiple modes, different types of skewness, etc., but they can also be employed to classify observations from heterogeneous data sets. In this paper, we study mixtures of distributions with normal, gamma, and Gumbel components. Moving away from the standard normal setting, gamma mixtures are developed in order to model strictly positive hydrological data and Gumbel mixtures for extreme variates. Since the data analyzed can exhibit dependency through time, we treat both the independent and dependent cases, where the latter is modeled through a Markov process. A fairly unified approach is adopted for the different distributions and the problem is treated from the Bayesian perspective, which enables us to use marginal densities to automatically compare the adequacy of the different models for a given data set. This model‐selection framework allows us to formally test the relevance of using mixture models by computing the marginal likelihoods of single distribution models and to verify the presence of a persistence in the time series by comparing independent and identically distributed (IID) and Markovian mixture models.
Storms, floods, and the science of atmospheric rivers
Authors: Ralph F. M. , Dettinger M. D.
Published: August 2011

Imagine a stream of water thousands of kilometers long and as wide as the distance between New York City and Washington, D. C., flowing toward you at 30 miles per hour. No, this is not some hypothetical physics problem—it is a real river, carrying more water than 7–15 Mississippi Rivers combined. But it is not on land. It's a river of water vapor in the atmosphere. Atmospheric rivers (ARs) are narrow corridors of water vapor transport in the lower atmosphere that traverse long swaths of the Earth's surface as they bind together the atmospheric water cycle (Figure 1). The characteristic (indeed defining) dimensions of these ARs are (1) integrated water vapor (IWV) concentrations such that if all the vapor in the atmospheric column were condensed into liquid water, the result would be a layer 2 or more centimeters thick; (2) wind speeds of greater than 12.5 meters per second in the lowest 2 kilometers; and (3) a shape that is long and narrow, no more than 400–500 kilometers wide, and extending for thousands of kilometers, sometimes across entire ocean basins.
Assessing El Niño Southern Oscillation variability during the past millennium
Authors: Khider D. , Stott L. D. , Emile‐Geay J. , Thunell R. , Hammond D. E.
Published: August 2011

We present a reconstruction of El Niño Southern Oscillation (ENSO) variability spanning the Medieval Climate Anomaly (MCA, A.D. 800–1300) and the Little Ice Age (LIA, A.D. 1500–1850). Changes in ENSO are estimated by comparing the spread and symmetry of δ18O values of individual specimens of the thermocline‐dwelling planktonic foraminifer Pulleniatina obliquiloculata extracted from discrete time horizons of a sediment core collected in the Sulawesi Sea, at the edge of the western tropical Pacific warm pool. The spread of individual δ18O values is interpreted to be a measure of the strength of both phases of ENSO while the symmetry of the δ18O distributions is used to evaluate the relative strength/frequency of El Niño and La Niña events. In contrast to previous studies, we use robust and resistant statistics to quantify the spread and symmetry of the δ18O distributions; an approach motivated by the relatively small sample size and the presence of outliers. Furthermore, we use a pseudo‐proxy approach to investigate the effects of the different paleo‐environmental factors on the statistics of the δ18O distributions, which could bias the paleo‐ENSO reconstruction. We find no systematic difference in the magnitude/strength of ENSO during the Northern Hemisphere MCA or LIA. However, our results suggest that ENSO during the MCA was skewed toward stronger/more frequent La Niña than El Niño, an observation consistent with the medieval megadroughts documented from sites in western North America.
Stochastic relationships for periodic responses in randomly heterogeneous aquifers
Authors: Trefry M. G. , McLaughlin D. , Lester D. R. , Metcalfe G. , Johnston C. D. , Ord A.
Published: August 2011

The aim of this work is to develop a theoretical framework for the analysis of groundwater head oscillations commonly observed in bores near boundaries of surface water bodies that are subject to periodic variations in stage height. Restricting attention to the linear groundwater flow equation, the dynamics of head variations induced by periodic modes acting at boundaries are governed by a complex‐valued time‐independent equation parameterized by the modal frequency of interest. For randomly heterogeneous aquifers the hydraulic conductivity field may be regarded as a spatial random variable. Stochastic relationships between the conductivity spectrum and the induced head oscillation spectrum are generated from a stochastic perturbation approach. Spatial correlative relationships are derived for several stochastic models incorporating up to three spatial dimensions. Explicit calculations of head oscillation autocovariances and spectral densities are parameterized by conductivity statistics, including integral scale and variance, and by modal frequency. The results show that time domain head responses to periodic boundary forcing are strongly dependent on multidimensional effects and on spatial correlation structure. Computational simulations show that the stochastic variance estimators match simulated head fluctuation variances for a range of modal frequencies and aquifer diffusivities and that joint inversion of conductivity integral scale and variance is possible with moderate numbers of sampling points.
Correcting rainfall using satellite‐based surface soil moisture retrievals: The Soil Moisture Analysis Rainfall Tool (SMART)
Authors: Crow W. T. , van den Berg M. J. , Huffman G. J. , Pellarin T.
Published: August 2011

Recently, Crow et al. (2009) developed an algorithm for enhancing satellite‐based land rainfall products via the assimilation of remotely sensed surface soil moisture retrievals into a water balance model. As a follow‐up, this paper describes the benefits of modifying their approach to incorporate more complex data assimilation and land surface modeling methodologies. Specific modifications improving rainfall estimates are assembled into the Soil Moisture Analysis Rainfall Tool (SMART), and the resulting algorithm is applied outside the contiguous United States for the first time, with an emphasis on West African sites instrumented as part of the African Monsoon Multidisciplinary Analysis experiment. Results demonstrate that the SMART algorithm is superior to the Crow et al. baseline approach and is capable of broadly improving coarse‐scale rainfall accumulations measurements with low risk of degradation. Comparisons with existing multisensor, satellite‐based precipitation data products suggest that the introduction of soil moisture information from the Advanced Microwave Scanning Radiometer via SMART provides as much coarse‐scale (3 day, 1°) rainfall accumulation information as thermal infrared satellite observations and more information than monthly rain gauge observations in poorly instrumented regions.
Trapped particle effects in long-time nonlinear Landau damping
Authors: Hou Y. W. , Ma Z. W. , Yu M. Y.
Published: August 2011

The long-time behavior of nonlinear Landau damping is investigated by numerically solving the Vlasov-Poisson system. The period and strength of the trapped electron oscillations are considered in detail. The results are interpreted in terms of a simple weighted-average oscillator model that takes into account of the dominance of shallowly trapped electrons.
Empirical pseudopotential calculations of the band structure and ballistic conductance of strained [001], [110], and [111] silicon nanowires
Authors: Kim Jiseok , Fischetti Massimo V.
Published: August 2011

The electronic band structure of hydrogen passivated, square cross-section, uniaxially strained [001], [110], and [111] silicon nanowires (Si NWs) has been calculated using nonlocal empirical pseudopotentials calibrated to yield the correct work function and benchmarked against first-principles calculations. We present results regarding the dependence and direct/indirect nature of the bandgap on wire diameter and uniaxial strain as well as the ballistic conductance and effective mass. As a result of practical interest, we have found that the largest ballistic electron conductance occurs for compressively strained large-diameter [001] wires while the smallest transport electron effective mass is found for larger-diameter [110] wires under tensile stress.
Efficiency enhancement of a-Si:H single junction solar cells by a-Ge:H incorporation at the p+ a-SiC:H/transparent conducting oxide interface
Authors: Kim Jeehwan , Abou-Kandil Ahmed I. , Hong Augustin J. , Saad Mohamed M. , Sadana Devendra K. , Chen Tze-Chiang
Published: August 2011

Carbon (C) incorporation in the p+ hydrogenated amorphous silicon (a-SiC:H) is highly desirable for a-Si:H based solar cells because of the following reasons: (i) it increases the band gap of the p+ layer to ∼2 eV, which allows a majority of the sun light to pass through the thin p+ layer (∼15 nm) and get absorbed in the underlying intrinsic a-Si:H layer, and (ii) it enhances built-in potential of the a-Si:H p-i-n stack, resulting in enhanced short circuit current (JSC) and open circuit voltage (VOC). Hence, it is a desire to incorporate the highest possible C % in the p+ a-Si:H. However, C incorporation results in a Schottky barrier at the p+ a-SiC:H/transparent conducting oxide (TCO) interface, which degrades the fill factor (FF) of the solar cell. In this paper, we present a method that increases the C incorporation in p+ a-SiC:H but without adversely affecting the FF, by adding a thin layer of hydrogenated amorphous germanium (a-Ge:H) buffer at the p+ a-SiC:H/TCO interface. The presence of a-Ge:H can either minimize or eliminate the Schottky barrier. We demonstrate ∼25% enhanced efficiency of the a-Si:H solar cell by using the a-Ge:H interfacial buffer compared to that without an a-Ge:H interfacial layer.
Magnetic signature of symmetry reduction in epitaxial La0.67Sr0.33MnO3 films
Authors: Barua Radhika , Lewis L. H. , Heiman D.
Published: August 2011

The magnetic properties of epitaxially grown La0.67Sr0.33MnO3 perovskite thin films were investigated to elucidate an unexpected broken symmetry between orthogonal [100] and [010] inplane directions, resulting from the magnetostructural coupling between the film and the cubic SrTiO3 (001) substrate. The films were synthesized by molecular beam epitaxy with either complete or zero A-site cation disorder. Magnetization measured in [100] and [010] directions shows differences that signal a reduction of the in-plane cubic symmetry only for T < 290 K. The magnetization asymmetry is more robust in the film with complete A-site disorder. These results are attributed to a dominant Mn3+ character at the film-substrate interface and an associated out-of-plane bonding character with hypothesized origins in both charge imbalance and strain effects.
Landscape variables influencing forest fires in central Spain
Authors: Moreno José M. , Viedma Olga , Zavala Gonzalo , Luna Belén
Published: August 2011

In assessing fire risk, it is important to determine whether all areas in a landscape burn at similar rates. This goal is complicated by the limitations of burned-area data and the temporally dynamic nature of landscapes. We assessed the differential degree of forest-fire burning for six landscape variables (land-use–land-cover type, distances to roads and towns, topography (slope, aspect, elevation)), each comprising several categories. The study area (95 × 55 km) was located in central Spain, and the study period covered 16 years. Landsat multispectral scanner images were used to annually map fire perimeters and to classify the landscape. We calculated an annual resource selection index for each category within a variable. The sizes and shapes of all fires occurring within a year were randomly distributed into the landscape 1000 times, and the corresponding resource selection index was calculated. This provided a null random-burning model against which we tested the actual resource selection index of the fires in each year. Pine woodlands showed consistent and significant positive fire selectivity, whereas deciduous woodlands showed consistent and significant negative selectivity. No differences in the resource selection indices of land-use–land-cover types were found between large (>100 ha) and small fires (<100 ha). Fires positively selected (resource selection index >1) areas at small or intermediate distances to towns and intermediate distances to roads. Selectivity for topographic variables was less marked. Our study demonstrates that landscape variables defining composition (land-use–land-cover type) or proximity to human influence are important factors for fire risk.