bluuebunny/crossref_metadata_2025 huggingface dataset:
Expanding Laparoscopic Cholecystectomy to Rural Mongolia
Authors: Straub Catherine M. , Price Raymond R. , Matthews Douglas , Handrahan Diana L. , Sergelen Davaatseren
Published: February 2011

Background

Although laparoscopic cholecystectomy was first introduced in Mongolia in 1994, the benefits of the laparoscopic approach have been largely unavailable to the majority of the population. The burden of gallbladder disease in Mongolia is significant. Despite the barriers to expanding laparoscopic surgery in Mongolia (lack of physical resources and adequate training opportunities, a difficult political situation, and an austere environment), the Health Sciences University of Mongolia (HSUM) began looking for ways to further the development of laparoscopy for the entire country, including the rural areas where half the population resides.

Methods

Combined didactic and practical training courses lasting 2 weeks were developed collaboratively by a private nongovernmental organization and HSUM. The courses were taught at tertiary care centers in the capital city (Ulaanbaatar) and in a smaller, rural city (Erdenet), the regional northern referral center. Demographic data, preoperative diagnosis, ultrasound and operative findings, operative times, length of hospital stay, and intraoperative and postoperative complication rates were compared from 2007–2008 from hospitals in Ulaanbaatar and Erdenet.

Results

A total of 36 surgeons participated in the training classes, and a total of 410 laparoscopic cholecystectomies were performed. Ultrasound was used as a diagnostic tool in all cases. There was no significant difference in intraoperative or postoperative complications between hospitals in the capital, where the procedures were performed by skilled laparoscopic surgeons, and in Erdenet, where the training courses first introduced laparoscopic cholecystectomy. Neither were there differences in complication rates between cases during the teaching and nonteaching periods.

Conclusions

Laparoscopic cholecystectomy can be expanded safely to the regional diagnostic referral centers in rural Mongolia through short‐term training courses as a method to markedly improve access and outcomes for the 50% of the country previously denied the benefits of minimally invasive surgery.
Setting the Bar for Laparoscopic Resection of Sporadic Insulinoma
Authors: Richards Melanie L. , Thompson Geoffrey B. , Farley David R. , Kendrick Michael L. , Service John F. , Vella Adrian , Grant Clive S.
Published: February 2011

Background

Laparoscopic insulinoma resection (LIR) for sporadic disease is increasingly supported as a feasible and safe operation in small series of patients. To determine whether LIR is an acceptable alternative to the open operation, it is necessary to compare LIR to historical controls. The purpose of this study was to identify the skills and technology needed for LIR and establish outcome standards.

Methods

A database of patients with benign sporadic insulinoma who underwent an open procedure at the Mayo Clinic was reviewed for demographics, imaging, operative/pathology reports, and outcomes. Outcomes were compared to a world‐wide meta‐analysis of patients who had undergone LIR reported in the English literature between 1996 and 2009.

Results

Two hundred fifteen patients underwent a primary open operation for benign sporadic insulinoma. Solitary tumors were found in 97%. Meta‐analysis identified 232 patients who underwent LIR. The open and LIR groups underwent comparable operations that included enucleations (64 vs. 68%) and distal pancreatectomies (28 vs. 35%) (p = 0.06). The mean estimated blood loss, operating time, and length of stay were comparable between the open and LIR groups (p = NS). Pancreatic fistula occurred more often in the LIR group (24 vs. 11%, p < 0.05). A curative operation was performed in 98% of control patients and in 99% of the LIR group (p = NS).

Conclusions

Multiple insulinomas are rare and a focused resection guided by imaging may be performed. LIR is associated with an increased incidence of pancreatic fistula. Success of LIR will depend on accurate multimodality preoperative imaging, skilled use of lap‐US to replace palpation for localization, and safe methods to dissect the tumor adjacent to the pancreatic duct.
Impacts of changes in climate variability on regional vegetation in China: NDVI‐based analysis from 1982 to 2000
Authors: Meng Meng , Ni Jian , Zong Meijuan
Published: February 2011

Three methods were used to distinguish the characteristics of changes in climate variability and normalized difference vegetation index (NDVI) during the period from 1982 to 2000 in China. Great changes in climate variability and an increased trend in NDVI were observed. The changes in precipitation variability were greater than the changes in temperature variability in each month, which is attributed to changes in the monsoon system in East Asia. The abrupt changes in climate and NDVI were more significant in 1983 than in the other years due to the impacts of El Niño/Southern Oscillation (ENSO). Using these results, the influences of changes in climate variability on vegetation were studied in the whole nation, and eight regions were defined according to the vegetation division map of China. The results show that abrupt climate changes at a small scale cannot cause abrupt NDVI changes directly. At a nationwide level, over a longer time scale the persistence of above/below average temperature determines the changes in NDVI; at a shorter time scale, changes in the magnitude of precipitation influence NDVI significantly. Such regional climate variability affects vegetation in different ways owing to the diversity of vegetation types, climatic conditions and topography of the land.
Percentage of protein, lipids, and carbohydrates in the diet of badger (Meles meles) populations across Europe
Authors: Remonti Luigi , Balestrieri Alessandro , Prigioni Claudio
Published: February 2011

Although originally evolved as predators, several species of mammalian carnivores exhibit a great trophic diversity, ranging from hypercarnivory to a high consumption of vegetable food. Habitat characteristics influence food availability and consequently could affect the nutritional composition of the diet of generalist species. By reviewing the available literature, we tested the hypothesis that intraspecific differences in the food habits of badgers (Meles meles) living in different habitats across Europe could affect the percentage of macronutrients (i.e., protein, lipids, and carbohydrates) in their diet. Notwithstanding the different composition of the diet, the percentage of protein and lipids fed by badgers did not vary among temperate forest‐pasture mosaics, Mediterranean woodlands, or scrublands and arable lands, suggesting a certain form of regulation of the diet balance. The percentage of carbohydrates was similar in the first two habitats, while it was fivefold higher in arable lands, where cereals were the main food of badgers and were consumed throughout the year. Earthworm consumption by badgers was positively related to the latitude, while the lack of any latitudinal or altitudinal pattern in protein consumption reflected the absence of a gradient in carnivory. A slight inverse latitudinal gradient in lipids consumption probably depended on the use, in southern Europe, of vegetal foods rich in lipids. We hypothesize that in agricultural landscapes dominated by crop cultivations, the decline of animal prey (i.e., earthworms, insects, and vertebrates) due to habitat loss forced badgers to increase the percentage of protein in their diet by over‐eating cereals, with the consequence of a disproportionate increase in carbohydrate consumption.
Plant clipping may cause overestimation of soil respiration in a Tibetan alpine meadow, southwest China
Authors: Li Guoyong , Sun Shucun
Published: February 2011

The chamber‐based method is currently the most popular approach used for measuring soil respiration of various ecosystems. When this method is applied, aboveground plant tissues within the chamber need to be clipped some time (usually 24 h) before measuring soil respiration. However, plant clipping may change soil temperature and hence soil respiration because soil respiration is highly temperature‐dependent, particularly in cold regions. To determine to what extent soil respiration may be changed by the clipping, we measured soil temperature and respiration of an alpine meadow of southwest China using a chamber‐based method over an annual cycle. Based on the measurements, an exponential equation was built to describe the relationship between soil respiration and temperature. Concurrently we measured the soil temperature in clipped and unclipped plots on sunny days of the study months in another independent experiment; subsequently soil respiration was estimated for these plots using the exponential equation. Though daily mean soil temperature was insignificantly different between the clipped and unclipped plots, the clipping increased soil temperature at 5 cm depth by up to 4.3°C at daytime but decreased by up to 1.4°C at nighttime during the growing season. The changes were 2.2 and 1.5°C at daytime and nighttime, respectively, in the non‐growing season. It was calculated that the clipping manipulation caused an overestimation of soil respiration by 28.6 and 21.2% for the growing and non‐growing seasons, respectively; nevertheless, this calculated overestimation should differ from the actual one because the data were collected on sunny days only.
Integrated Countercurrent Two‐Stage Extraction and Cream Demulsification in Enzyme‐Assisted Aqueous Extraction of Soybeans
Authors: de Moura J. M. L. N. , Maurer D. , Jung S. , Johnson L. A.
Published: February 2011

Countercurrent two‐stage extraction and cream demulsification were fully integrated and demonstrated on laboratory scale (2 kg soybeans) wherein the enzyme used for demulsifying the cream was used in the extraction steps of enzyme‐assisted aqueous extraction processing (EAEP). Protease enzyme (Protex 6L) entered the integrated EAEP process in the demulsification step and the skim, which contained the enzyme, resulting from breaking the cream emulsion was recycled upstream into the second extraction stage and then to the first extraction stage. Oil, protein and solids extraction yields of 96.1 ± 1.4%, 89.3 ± 1.0%, and 81.2 ± 2.0%, respectively, were achieved with steady‐state operation of integrated EAEP. Higher degrees of protein hydrolysis (DH) were obtained when using the integrated process compared with the process when not recycling the enzyme. Higher extents of hydrolysis probably increased emulsion formation thereby affecting lipid distribution among the fractions. Overall free oil recovery was reduced due to more oil shifting to the skim fraction.
Zukunftsperspektiven mittel- und osteuropäischer Großwohnsiedlungen zwischen Wohnungsmarkt, Bewohnerinitiative und Förderpolitik
Authors: S. Neugebauer Carola , Wiest Karin , Krupickaite Dovile
Published: February 2011

The differentiation of housing supply and demand in Central-Eastern European urban regions since 1990 adumbrates the reassessment of socialist large scale housing estates as housing location. The importance of this market segment in terms of housing supply as well as its need for refurbishment stresses on the significance of large-scale housing estates in urban development. Against this background the authors analyse the current social and edificial situations in four selected large-scale housing estates in Central-Eastern Europe. Potential perspectives for its developments are discussed as opportunities and needs for action, resulting from the interplay of regional housing market structures, public policy of subsidies and dwellers’ behaviour between mobility and do-it-yourself initiatives.
Initial evidence for the role of CACNA1C on subcortical brain morphology in patients with bipolar disorder
Authors: Perrier E. , Pompei F. , Ruberto G. , Vassos E. , Collier D. , Frangou S.
Published: February 2011

Background

The polymorphism rs1006737 within the CACNA1C gene is associated with increased risk for bipolar disorder (BD) and variations in brain morphology and function of subcortical regions. Here we sought to investigate the influence of CACNA1C polymorphism on key subcortical brain structures implicated in the pathophysiology of BD.

Methods

Structural magnetic resonance imaging scans were acquired from 41 euthymic patients with BD and 40 healthy controls, who were also genotyped for the CACNA1C rs1006737 polymorphism. The effect of diagnosis, genotype and their interaction was examined in predefined volumes of interest in the basal ganglia, hypothalamus and amygdala extracted using SPM5.

Results

Carriers of the CACNA1C rs1006737 risk allele showed increased grey matter density in the right amygdala and right hypothalamus irrespective of diagnosis. An interaction between genotype and diagnosis was observed in the left putamen which was smaller in BD patients carrying the risk allele than in healthy controls.

Conclusions:

The CACNA1C rs1006737 polymorphism influences anatomical variation within subcortical regions involved in emotional processing.
The course of depressive symptoms and prescribing patterns of antidepressants in schizophrenia in a one-year follow-up study
Authors: Lako I.M. , Taxis K. , Bruggeman R. , Knegtering H. , Burger H. , Wiersma D. , Slooff C.J.
Published: February 2011

Background

Antidepressants are frequently prescribed in patients with psychotic disorders, but little is known about their effects in routine clinical practice. The objective was to investigate the prescribing patterns of antidepressants in relation to the course of depressive symptoms in patients with psychotic disorders.

Methods

A cohort of 214 Dutch patients with psychotic disorders received two assessments of somatic and psychiatric health, including a clinician-rated screening for depressive symptoms, as part of annual routine outcome monitoring.

Results

Depressive symptoms were prevalent among 43% (93) of the patients. Antidepressants were prescribed for 40% (86) of the patients and the majority 83% (71) continued this therapy after one year. Multivariable analysis showed that patients with more severe psychopathology had a higher risk to develop depressive symptoms the following year (OR [95% CI]=0.953 [0.912–0.995]). For patients with depressive symptoms at baseline, polypharmacy was a potential risk factor to keep having depressive symptoms (OR [95% CI]=1.593 [1.123–2.261]). Antidepressant use was not an independent predictor in both analyses.

Conclusions

Routine outcome monitoring in patients with psychotic disorders revealed a high prevalence of depressive symptoms. Antidepressants were frequently prescribed and continued in routine clinical practice.
Baseline and prodromal characteristics of first- versus multiple-episode mania in a French cohort of bipolar patients
Authors: Azorin J.-M. , Kaladjian A. , Adida M. , Fakra E. , Hantouche E. , Lancrenon S.
Published: February 2011

Objective:

To identify some of the main features of bipolar disorder for both first-episode (FE) mania and the preceding prodromal phase, in order to increase earlier recognition.

Methods:

One thousand and ninety manic patients (FE=81, multiple-episodes [ME]=1009) were assessed for clinical and temperamental characteristics.

Results:

Compared to ME, FE patients reported more psychotic and less depressive symptoms but were comparable with respect to temperamental measures and comorbid anxiety. The following independent variables were associated with FE mania: a shorter delay before correct diagnosis, greater substance use, being not divorced, greater stressors before current mania, a prior diagnosis of an anxiety disorder, lower levels of depression during index manic episode, and more suicide attempts in the past year.

Conclusion:

In FE patients, the diagnosis of mania may be overlooked, as they present with more psychotic symptoms than ME patients. The prodromal phase is characterised by high levels of stress, suicide attempts, anxiety disorders and alcohol or substance abuse. Data suggest to consider these prodromes as harmful consequences of temperamental predispositions to bipolar disorder that may concur to precipitate mania onset. Their occurrence should therefore incite clinicians to screen for the presence of such predispositions, in order to identify patients at risk of FE mania.
A conceptual model of valley incision, planation and terrace formation during cold and arid permafrost conditions of Pleistocene southern England
Authors: Murton Julian B. , Belshaw Roger K.
Published: February 2011

Staircases of gravelly river terrace deposits in southern England occupy valleys typically underlain by frost-susceptible and brecciated bedrocks. The valleys developed during the Quaternary by alternating episodes of (1) brecciation, incision and planation through the bedrock, forming wide low-relief erosion surfaces; and (2) aggradation in braidplains of gravel a few meters thick that bury the erosion surfaces. A conceptual model to account for some of the terraces proposes that brecciation resulted from ice segregation in the ice-rich layer in the upper meters of Pleistocene permafrost, making them vulnerable to fluvial thermal erosion and therefore predisposing the bedrock to planation. The low gradients of the valleys were adjusted such that rivers transferred fine materials out of the basins but lacked the competence to remove gravel, which therefore accumulated within floodplains. The model challenges the prevailing view of incision during climate transitions. It attributes incision and planation to very cold and arid permafrost conditions, when rivers had limited discharges and hillslopes supplied limited volumes of stony debris into valley bottoms.
Growth and instability of a laminar plume in a strongly stratified environment
Authors: LOMBARDI M. , CAULFIELD C. P. , COSSU C. , PESCI A. I. , GOLDSTEIN R. E.
Published: February 2011

Experimental studies of laminar plumes descending under gravity into stably stratified environments have shown the existence of a critical injection velocity beyond which the plume exhibits a bifurcation to a coiling instability in three dimensions or a sinuous instability in a Hele-Shaw flow. In addition, flow visualization has shown that, prior to the onset of the instability, a stable base flow is established in which the plume penetrates to a depth significantly smaller than the neutral buoyancy depth. Moreover, the fresh water that is viscously entrained by the plume recirculates within a ‘conduit’ whose boundary with the background stratification appears sharp. Beyond the bifurcation, the buckling plume takes the form of a travelling wave of varying amplitude, confined within the conduit, which disappears at the penetration depth. To determine the mechanisms underlying these complex phenomena, which take place at a strikingly low Reynolds number but a high Schmidt number, we study here a two-dimensional arrangement, as it is perhaps the simplest system which possesses all the key experimental features. Through a combination of numerical and analytical approaches, a scaling law is found for the plume's penetration depth within the base flow (i.e. the flow where the instability is either absent or artificially suppressed), and the horizontal cross-stream velocity and concentration profile outside the plume are determined from an asymptotic analysis of a simplified model. Direct numerical simulations show that, with increasing flow rate, a sinuous global mode is destabilized giving rise to the self-sustained oscillations as in the experiment. The sinuous instability is shown to be a consequence of the baroclinic generation of vorticity, due to the strong horizontal gradients at the edge of the conduit, a mechanism that is relevant even at very low Reynolds numbers. Despite the strength of this instability, the penetration depth is not significantly affected by it, instead being determined by the properties of the plume in the vicinity of the source. This scenario is confirmed by a local stability analysis. A finite region of local absolute instability is found near the source for sinuous modes prior to the onset of the global instability. Sufficiently far from the source the flow is locally stable. Near the onset of the global instability, varicose modes are also found to be locally, but only convectively, unstable.
A single self-deceived or several subselves divided?
Authors: Kenrick Douglas T. , White Andrew E.
Published: February 2011

Would we lie to ourselves? We don't need to. Rather than a single self equipped with a few bivariate processes, the mind is composed of a dissociated aggregation of subselves processing qualitatively different information relevant to different adaptive problems. Each subself selectively processes the information coming in to the brain as well as information previously stored in the brain.
Self-deceive to countermine detection
Authors: Lu Hui Jing , Chang Lei
Published: February 2011

Having evolved to escape detection of deception completely, self-deception must respond to social conditions registering different probabilities of detection. To be adaptive, it must have a mechanism to keep truthful information temporarily from the self during deception and retrieve it after deception. The memory system may serve this mechanism and provides a paradigm in which to conduct research on self-deception.
Reviewing the logic of self-deception
Authors: Fridland Ellen
Published: February 2011

I argue that framing the issue of motivated belief formation and its subsequent social gains in the language of self-deception raises logical difficulties. Two such difficulties are that (1) in trying to provide an evolutionary motive for viewing self-deception as a mechanism to facilitate other-deception, the ease and ubiquity of self-deception are undermined, and (2) because after one has successfully deceived oneself, what one communicates to others, though untrue, is not deceptive, we cannot say that self-deception evolved in order to facilitate the deception of others.
Understanding self-deception demands a co-evolutionary framework
Authors: Gangestad Steven W.
Published: February 2011

The foundational theme of the target article is that processes of self-deception occur in a functional context: a social one through which self-deceptive processes enhance fitness by affecting an actor's performances. One essential component of this context not addressed explicitly is that audiences should have been selected to resist, where possible, enhancements falsely bolstered by self-deception. Theoretical implications follow.
The selfish goal: Self-deception occurs naturally from autonomous goal operation
Authors: Huang Julie Y. , Bargh John A.
Published: February 2011

Self-deception may be a natural consequence of active goal operation instead of an adaptation for negotiating the social world. We argue that because autonomous goal programs likely drove human judgment and behavior prior to evolution of a central executive or “self,” these goal programs can operate independently to attain their desired end states and thereby produce outcomes that “deceive” the individual.
Representations and decision rules in the theory of self-deception
Authors: Pinker Steven
Published: February 2011

Self-deception is a powerful but overapplied theory. It is adaptive only when a deception-detecting audience is in the loop, not when an inaccurate representation is invoked as an internal motivator. First, an inaccurate representation cannot be equated with self-deception, which entails two representations, one inaccurate and the other accurate. Second, any motivational advantages are best achieved with an adjustment to the decision rule on when to act, not with a systematic error in an internal representation.
The evolutionary route to self-deception: Why offensive versus defensive strategy might be a false alternative
Authors: Frey Ulrich , Voland Eckart
Published: February 2011

Self-deception may be the result of social manipulation and conflict management of social in-groups. Although self-deception certainly has offensive and defensive aspects, a full evolutionary understanding of this phenomenon is not possible until strategies of other parties are included into a model of self-perception and self-representation.
Reflections on self-deception
Authors: von Hippel William , Trivers Robert
Published: February 2011

Commentators raised 10 major questions with regard to self-deception: Are dual representations necessary? Does self-deception serve intrapersonal goals? What forces shape self-deception? Are there cultural differences in self-deception? What is the self? Does self-deception have costs? How well do people detect deception? Are self-deceivers lying? Do cognitive processes account for seemingly motivational ones? And how is mental illness tied up with self-deception? We address these questions and conclude that none of them compel major modifications to our theory of self-deception, although many commentators provided helpful suggestions and observations.
Culture of deception
Authors: Gorelik Gregory , Shackelford Todd K.
Published: February 2011

We examine the self-deceptive aspects of religion and nationalism. By embracing various religious or political ideals, regardless of their truth, our ancestors could have enhanced their confidence, solidified their social ties, and manipulated their reproductive rivals. This use of culture as one's extended phenotype may increase the spread of misinformation and create global webs of deception and self-deception.
Associations and Democracy
Authors: Cohen Joshua , Rogers Joel
Published: February 2011

Since the publication of John Rawls'sA Theory of Justice, normative democratic theory has focused principally on three tasks: refining principles of justice, clarifying the nature of political justification, and exploring the public policies required to ensure a just distribution of education, health care, and other basic resources. Much less attention has been devoted to examining the political institutions and social arrangements that might plausibly implement reasonable political principles. Moreover, the amount of attention paid to issues of organizational and institutional implementation has varied sharply across the different species of normative theory. Neoliberal theorists, concerned chiefly with protecting liberty by taming power, and essentially hostile to the affirmative state, have been far more sensitive to such issues than egalitarian-democratic theorists, who simultaneously embrace classically liberal concerns with choice, egalitarian concerns with the distribution of resources, and a republican emphasis on the values of citizen participation and public debate (we sketch such a conception below in Section I). Neglect of how such values might be implemented has deepened the vulnerability of egalitarian-democratic views to the charge of being unrealistic: “good in theory but not so good in practice.”
Societal, Structural, and Conceptual Changes in Mathematics Teaching: Reform Processes in France and Germany over the Twentieth Century and the International Dynamics
Authors: Gispert Hélène , Schubring Gert
Published: February 2011

Argument

This paper studies the evolution of mathematics teaching in France and Germany from 1900 to about 1980. These two countries were leading in the processes of international modernization. We investigate the similarities and differences during the various periods, which showed to constitute significant time units and this in a remarkably parallel manner for the two countries. We argue that the processes of reform concerning the teaching of this major school subject are not understandable from within mathematics education or even within the school system. Rather, the evolution of the processes of reform prove to be intimately tied to changing conceptions of modernity according to respective social and cultural values and to changing epistemological conceptions of mathematics. It is particularly novel that we show the key impact of the changing social status of primary schooling for these modernization processes.
Asymptotics for First-Passage Times on Delaunay Triangulations
Authors: PIMENTEL LEANDRO P. R.
Published: February 2011

In this paper we study planar first-passage percolation (FPP) models on random Delaunay triangulations. In [14], Vahidi-Asl and Wierman showed, using sub-additivity theory, that the rescaled first-passage time converges to a finite and non-negative constant μ. We show a sufficient condition to ensure that μ>0 and derive some upper bounds for fluctuations. Our proofs are based on percolation ideas and on the method of martingales with bounded increments.
Szemerédi's Regularity Lemma for Matrices and Sparse Graphs
Authors: SCOTT ALEXANDER
Published: February 2011

Szemerédi's Regularity Lemma is an important tool for analysing the structure of dense graphs. There are versions of the Regularity Lemma for sparse graphs, but these only apply when the graph satisfies some local density condition. In this paper, we prove a sparse Regularity Lemma that holds for all graphs. More generally, we give a Regularity Lemma that holds for arbitrary real matrices.
Clitic placement in Spanish–English bilingual children
Authors: PÉREZ-LEROUX ANA TERESA , CUZA ALEJANDRO , THOMAS DANIELLE
Published: February 2011

Can transfer occur in child bilingual syntax when surface overlap does not involve the syntax-pragmatics interface? Twenty-three Spanish/English bilingual children participated in an elicited imitation study of clitic placement in Spanish restructuring contexts, where variable word order is not associated with pragmatic or semantic factors. Bilingual children performed poorly with preverbal clitics, the order that does not overlap with English. Distinct bilingual patterns emerged: backward repositioning, omissions (for simultaneous bilinguals) and a reduction in forward repositioning bias. We conclude that transfer should be defined in lexical terms as the result of priming effects leading to shifts in lexical items.
Endoplasmic reticulum stress and lipid dysregulation
Authors: Colgan Stephen M. , Al-Hashimi Ali A. , Austin Richard C.
Published: February 2011

Cellular cholesterol homeostasis is a fundamental and highly regulated process. Transcription factors known as sterol regulatory element binding proteins (SREBPs) coordinate the expression of many genes involved in the biosynthesis and uptake of cholesterol. Dysregulation of SREBP activation and cellular lipid accumulation has been associated with endoplasmic reticulum (ER) stress and activation of the unfolded protein response (UPR). This review will provide an overview of ER stress and the UPR as well as cholesterol homeostasis and SREBP regulation, with an emphasis on their interaction and biological relevance.
Radar rainfall estimation of stratiform winter precipitation in the Belgian Ardennes
Authors: Hazenberg P. , Leijnse H. , Uijlenhoet R.
Published: February 2011

Radars are known for their ability to obtain a wealth of information about spatial storm field characteristics. Unfortunately, rainfall estimates obtained by this instrument are known to be affected by multiple sources of error. Especially for stratiform precipitation systems, the quality of radar rainfall estimates starts to decrease at relatively close ranges. In the current study, the hydrological potential of weather radar is analyzed during a winter half‐year for the hilly region of the Belgian Ardennes. A correction algorithm is proposed which corrects the radar data for errors related to attenuation, ground clutter, anomalous propagation, the vertical profile of reflectivity (VPR), and advection. No final bias correction with respect to rain gauge data was implemented because such an adjustment would not add to a better understanding of the quality of the radar data. The impact of the different corrections is assessed using rainfall information sampled by 42 hourly rain gauges. The largest improvement in the quality of the radar data is obtained by correcting for ground clutter. The impact of VPR correction and advection depends on the spatial variability and velocity of the precipitation system. Overall during the winter period, the radar underestimates the amount of precipitation as compared to the rain gauges. Remaining differences between both instruments can be attributed to spatial and temporal variability in the type of precipitation, which has not been taken into account.
Global distribution patterns of distinct clades of the photosynthetic picoeukaryote Ostreococcus
Authors: Demir-Hilton Elif , Sudek Sebastian , Cuvelier Marie L , Gentemann Chelle L , Zehr Jonathan P , Worden Alexandra Z
Published: February 2011

Ostreococcus is a marine picophytoeukaryote for which culture studies indicate there are ‘high-light’ and ‘low-light’ adapted ecotypes. Representatives of these ecotypes fall within two to three 18S ribosomal DNA (rDNA) clades for the former and one for the latter. However, clade distributions and relationships to this form of niche partitioning are unknown in nature. We developed two quantitative PCR primer-probe sets and enumerated the proposed ecotypes in the Pacific Ocean as well as the subtropical and tropical North Atlantic. Statistical differences in factors such as salinity, temperature and NO3 indicated the ecophysiological parameters behind clade distributions are more complex than irradiance alone. Clade OII, containing the putatively low-light adapted strains, was detected at warm oligotrophic sites. In contrast, Clade OI, containing high-light adapted strains, was present in cooler mesotrophic and coastal waters. Maximal OI abundance (19 555±37 18S rDNA copies per ml) was detected in mesotrophic waters at 40 m depth, approaching the nutricline. OII was often more abundant at the deep chlorophyll maximum, when nutrient concentrations were significantly higher than at the surface (stratified euphotic zone waters). However, in mixed euphotic-zone water columns, relatively high numbers (for example, 891±107 18S rDNA copies per ml, Sargasso Sea, springtime) were detected at the surface. Both Clades OI and OII were found at multiple euphotic zone depths, but co-occurrence at the same geographical location appeared rare and was detected only in continental slope waters. In situ growth rate estimates using these primer-probes and better comprehension of physiology will enhance ecological understanding of Ostreococcus Clades OII and OI which appear to be oceanic and coastal clades, respectively.
Cardiorespiratory Fitness, Different Measures of Adiposity, and Total Cancer Mortality in Women
Authors: Farrell Stephen W. , Finley Carrie E. , McAuley Paul A. , Frierson Georita M.
Published: February 2011

The objective was to examine associations among cardiorespiratory fitness (CRF), adiposity, and cancer mortality in women. Healthy women (N = 14,256) without cancer history completed a baseline health examination 1970–2005. Measures included BMI, percent body fat (%Fat), and CRF quantified as duration of a maximal treadmill test. CRF was classified as low (quintile 1), moderate (Q2–3), and high fit (Q4–5) by age. Standard BMI cutpoints were used, while participants were classified by %Fat quintiles. Cancer mortality rates were calculated following age, exam year, and smoking adjustment. During a mean follow‐up period of 15.2 ± 9.4 years, 250 cancer deaths occurred. Adjusted mortality rates across BMI groups were 4.6, 5.7, and 8.8 (P trend 0.08); %Fat 3.0, 4.9, 2.9, 3.8, and 6.9 (P trend 0.17); and CRF 7.9, 5.5, and 2.9 (P trend 0.003). When grouped into categories of fit and unfit (upper 80% and lower 20% of CRF distribution), and using BMI as the adiposity exposure, cancer mortality rates of unfit‐obese women were significantly higher than fit‐normal weight women (9.8 vs. 4.1 deaths/10,000 woman‐years; P = 0.02), while fit‐overweight and fit‐obese women had no greater risk of mortality than fit‐normal weight women. Using %Fat as the adiposity exposure, unfit‐obese women tended to have higher cancer mortality than fit‐normal weight women (7.0 vs. 3.3 deaths/10,000 woman‐years, P = 0.10). Higher levels of CRF are associated with lower cancer mortality risk in women and attenuate the risk of cancer mortality in overweight women. Using adiposity measures to estimate cancer mortality risk in women can be potentially misleading unless CRF is considered.
Circulating Omentin as a Novel Biomarker of Endothelial Dysfunction
Authors: Moreno‐Navarrete José Maria , Ortega Francisco , Castro Antoni , Sabater Mónica , Ricart Wifredo , Fernández‐Real José Manuel
Published: February 2011

Omentin is a novel soluble lectin expressed mainly in the stromal‐vascular cells from visceral adipose tissue with vasodilator effect in isolated blood vessels. To gain insight in the relationship between obesity and cardiovascular risk factors, we aimed to explore the interaction among circulating omentin, metabolic parameters, and endothelial function. Circulating omentin (enzyme‐linked immunosorbent assay) was studied in 248 white men (148 with normal glucose tolerance (NGT) and 100 with impaired glucose tolerance (IGT)). Insulin sensitivity was measured using the frequently sampled intravenous glucose tolerance test. Vascular reactivity was measured by high‐resolution ultrasound of the brachial artery. Circulating omentin concentration was significantly increased in lean compared with overweight and obese subjects (53.7 ± 16.9 vs. 45.2 ± 16.8 and vs. 40.1 ± 15.5 ng/ml, P < 0.0001). Circulating omentin concentration correlated with age, BMI, waist‐to‐hip ratio (WHR), percentage of fat mass, systolic and diastolic blood pressure, endothelium‐dependent and independent vasodilation (EDV and EIV), C‐reactive protein, and interleukin‐6 (IL‐6). In IGT subjects, circulating omentin concentration also correlated with insulin sensitivity, although this association did not remain significant after controlling for BMI. In a multiple linear regression analysis, circulating omentin concentration (P = 0.01), systolic blood pressure (P = 0.04), and BMI (P = 0.04) contributed independently to EDV after controlling for age and C‐reactive protein in IGT subjects. In NGT subjects, only circulating omentin concentration (P = 0.01) was significantly associated with EDV. In conclusion, circulating omentin concentration could be a useful marker of endothelial function.
Obesity, Overweight, and Their Life Course Trajectories in Veterans and Non‐Veterans
Authors: Koepsell Thomas D. , Littman Alyson J. , Forsberg Christopher W.
Published: February 2011

Veterans comprise a large and growing segment of the US population. Results from national telephone surveys suggest higher prevalence of overweight among Veterans compared with demographically similar non‐Veterans, based on self‐reported height and weight. Using 1999–2008 data from the National Health and Nutrition Examination Survey (NHANES), we compared 3,768 Veterans and 21,974 non‐Veterans on: (i) several measures of adiposity based on direct anthropometry; (ii) life‐course of self‐reported BMI; and (iii) behaviors related to weight loss or maintenance. Whether Veterans were more likely than demographically similar non‐Veterans to be obese or overweight depended on the adiposity measure employed. On BMI, Veterans were about equally likely to be obese (30+ kg/m2), but more likely to be overweight (25–29.9 kg/m2) by both self‐report and by direct measurement (significantly so only by self‐report). On waist‐stature ratio, a roughly similar pattern was observed. On waist circumference, Veterans tended to have larger values than demographically similar non‐Veterans, with more Veterans in the largest two categories. But on dual‐photon X‐ray absorptiometry, Veterans were less likely to have 35+% body fat than non‐Veterans of similar age, gender, and race/ethnicity. Life‐course trends in self‐reported BMI suggested a possible burst of weight gain after military discharge. These results suggest that Veterans may, on average, have less excess body fat than non‐Veterans—a pattern not revealed by standard anthropometric measures.
Poly(urethane/malonamide) dendritic structures featuring blocked/deblocked isocyanate units
Authors: Chen Yung-Chung , Wu Wen-Yi , Juang Tzong-Yuan , Dai Shenghong A. , Su Wen-Chiung , Liu Ying-Ling , Lee Rong-Ho , Jeng Ru-Jong
Published: February 2011

Novel reactive dendritic structures possessing terminal blocked isocyanates were synthesized, which allows further replacement of reactive exterior groups with desired functionality.
Variational second order density matrix study of $\mathrm{F_3^-}$F3−: Importance of subspace constraints for size-consistency
Authors: van Aggelen Helen , Verstichel Brecht , Bultinck Patrick , Neck Dimitri Van , Ayers Paul W. , Cooper David L.
Published: February 2011

Variational second order density matrix theory under “two-positivity” constraints tends to dissociate molecules into unphysical fractionally charged products with too low energies. We aim to construct a qualitatively correct potential energy surface for \documentclass[12pt]{minimal}\begin{document}$\mathrm{F_3^-}$\end{document}F3− by applying subspace energy constraints on mono- and diatomic subspaces of the molecular basis space. Monoatomic subspace constraints do not guarantee correct dissociation: the constraints are thus geometry dependent. Furthermore, the number of subspace constraints needed for correct dissociation does not grow linearly with the number of atoms. The subspace constraints do impose correct chemical properties in the dissociation limit and size-consistency, but the structure of the resulting second order density matrix method does not exactly correspond to a system of noninteracting units.
Charge regulation and ionic screening of patchy surfaces
Authors: Boon N. , van Roij R.
Published: February 2011

The properties of surfaces with charge-regulated patches are studied using nonlinear Poisson–Boltzmann theory. Using a mode expansion to solve the nonlinear problem efficiently, we reveal the charging behavior of Debye-length sized patches. We find that the patches charge up to higher charge densities if their size is relatively small and if they are well separated. The numerical results are used to construct a basic analytical model which predicts the average surface charge density on surfaces with patchy chargeable groups.
A promising concept for using near-surface measuring angles in angle-resolved x-ray photoelectron spectroscopy considering elastic scattering effects
Authors: Oswald S. , Oswald F.
Published: February 2011

The increasing number of applications of very thin films requires both reliable thin-layer and interface characterization. A powerful method for characterization in the nanometer thickness range is the angle-resolved x-ray photoelectron spectroscopy (ARXPS). This is a nondestructive depth-profiling method, which can provide elemental content as well as chemical information. Two of the drawbacks of ARXPS are, that it requires dedicated mathematical modeling and that, at least up until now, its use has been restricted away from near-surface angles. In this paper we present a method for the mathematical description of a few, hitherto unaccounted, measurement effects in order to improve the simulations of ARXPS data for complex surface structures. As an immediate application, we propose a simple algorithm to consider the effects of elastic scattering in the standard ARXPS data interpretation, which in principle would allow the use of the whole angular range for the analysis; thus leading to a significant increase in the usable information content from the measurements. The potential of this approach is demonstrated with model calculations for a few thin film examples.
Anomalous electrical transport properties of polyvinyl alcohol-multiwall carbon nanotubes composites below room temperature
Authors: Chakraborty G. , Gupta K. , Meikap A. K. , Babu R. , Blau W. J.
Published: February 2011

The dc and ac electrical transport property of polyvinyl alcohol-multiwall carbon nanotubes composites has been investigated within a temperature range 77≤T≤300 K and in the frequency range 20 Hz–1 MHz in presence as well as in absence of a transverse magnetic field up to 1 T. The dc conductivity follows variable range hopping model. The magnetoconductivity of the samples changes a sign from positive to negative with an increase in temperature which can be interpreted by the dominancy of the quantum interference effect over the wave function shrinkage effect. The ac conductivity follows a power law whereas the temperature dependence of frequency exponent s can be explained by correlated barrier hopping model. The dielectric behavior of the samples has been governed by the grain and grain boundary resistance and capacitance. The ac conductivity reduces with the application of magnetic field. Although the theoretical model to explain it, is still lacking, we may conclude that this is due to the increase in grain and grain boundary resistance by the application of magnetic field.
Beyond quantum microcanonical statistics
Authors: Fresch Barbara , Moro Giorgio J.
Published: February 2011

Descriptions of molecular systems usually refer to two distinct theoretical frameworks. On the one hand the quantum pure state, i.e., the wavefunction, of an isolated system is determined to calculate molecular properties and their time evolution according to the unitary Schrödinger equation. On the other hand a mixed state, i.e., a statistical density matrix, is the standard formalism to account for thermal equilibrium, as postulated in the microcanonical quantum statistics. In the present paper an alternative treatment relying on a statistical analysis of the possible wavefunctions of an isolated system is presented. In analogy with the classical ergodic theory, the time evolution of the wavefunction determines the probability distribution in the phase space pertaining to an isolated system. However, this alone cannot account for a well defined thermodynamical description of the system in the macroscopic limit, unless a suitable probability distribution for the quantum constants of motion is introduced. We present a workable formalism assuring the emergence of typical values of thermodynamic functions, such as the internal energy and the entropy, in the large size limit of the system. This allows the identification of macroscopic properties independently of the specific realization of the quantum state. A description of material systems in agreement with equilibrium thermodynamics is then derived without constraints on the physical constituents and interactions of the system. Furthermore, the canonical statistics is recovered in all generality for the reduced density matrix of a subsystem.
Control of c-axis orientation of L1-FePd in dual-phase-equilibrium FePd/Fe thin films
Authors: Ichitsubo T. , Takashima S. , Matsubara E. , Tsukimoto S. , Tamada Y. , Ono T.
Published: February 2011

This work establishes a method of controlling the c-axis-oriented structure of α-Fe (soft magnetic)/L10-FePd (hard magnetic) thin films in the dual-phase compositional region in thermal equilibrium. Two types of thin films were prepared; one is a single-layered thin film, and the other is a multilayered film, [FePd(x nm)/Fe(5 nm)]n (x: thickness, n: the number of multilayers), both of which are deposited on silica glass substrates. For single-layered films, the ordering process is retarded by phase separation that requires long-range diffusion. In this case, the ⟨111⟩ oriented domains preferentially grow from the film surface, and the c-axis-oriented structure is not obtained. On the contrary, for multilayered films, each FePd layer can undergo ordering without phase separation subject to the constraint of strong biaxial tensile stress resulting from the difference in the thermal contractions between Fe/FePd film and the silica glass substrate. Consequently, the L10 domains with c-axis orientation in the normal direction of the film surface are preferentially formed in the initial amorphouslike structure, eventually leading to the desired c-axis-oriented structure.