bluuebunny/crossref_metadata_2025 huggingface dataset:
Spectrum redistribution for cognitive radios using discriminatory spectrum double auction
Authors: Lu Luxi , Jiang Wei , Bai Lin , Chen Chen , He Jianhua , Xiang Haige , Luo Wu
Published: May 2011

With the reformation of spectrum policy and the development of cognitive radio, secondary users will be allowed to access spectrums licensed to primary users. Spectrum auctions can facilitate this secondary spectrum access in a market‐driven way. To design an efficient auction framework, we first study the supply and demand pressures and the competitive equilibrium of the secondary spectrum market, considering the spectrum reusability. In well‐designed auctions, competition among participants should lead to the competitive equilibrium according to the traditional economic point of view. Then, a discriminatory price spectrum double auction framework is proposed for this market. In this framework, rational participants compete with each other by using bidding prices, and their profits are guaranteed to be non‐negative. A near‐optimal heuristic algorithm is also proposed to solve the auction clearing problem of the proposed framework efficiently. Experimental results verify the efficiency of the proposed auction clearing algorithm and demonstrate that competition among secondary users and primary users can lead to the competitive equilibrium during auction iterations using the proposed auction framework. Copyright © 2011 John Wiley & Sons, Ltd.
Random time source protocol in wireless sensor networks and synchronization in industrial environments
Authors: Wang Fuqiang , Zeng Peng , Yu Haibin , Xiao Yang
Published: May 2011

Reliability is a crucial aspect of time synchronization for industrial wireless applications in wireless sensor networks. Existing time synchronization algorithms often provide good synchronization in laboratory environments; however, outdoor environments with associated radio interference influence the performance of time synchronization. In this paper, we propose a random time source protocol for industrial wireless applications in wireless sensor network synchronization. Each synchronized node randomly selects its time source for each period in order to prevent reliance on a fixed time source because this may lead to resynchronization once the source fails. We have implemented the algorithm on the SIA2420 platform using TinyOS, and the results show the reliability of our protocol. Copyright © 2011 John Wiley & Sons, Ltd.
Factors affecting mourning dove harvest in Missouri
Authors: Bonnot Thomas W. , Schulz John H. , Millspaugh Joshua J.
Published: May 2011

Mourning dove (Zenaida macroura) management efforts have focused on reducing uncertainties in harvest management at national and regional scales, but there remains considerable interest in issues related to local, intensively managed areas. Our objective was to evaluate effects of different local management strategies, including field management and regulations, and weather, on the number of hunts and the number of doves harvested annually. We collected harvest information from dove hunters, and area management characteristics from wildlife managers on 9 public hunting areas in Missouri, USA from 2005 to 2009. Number of hunts on an area was best explained by number of hectares of crop on the area; however, acreage above 50 ha offered limited increases in the number of hunts on a site. The most supported model for the number of doves harvested contained a positive effect of acreage of sunflowers (Helianthus annuus) in good or excellent condition. This model was followed by a closely competing model reflecting increases in the number of doves harvested when an area used daily lottery and shot‐type restrictions; however, complete overlap between these 2 regulations prevented separation of their individual effects. To manipulate hunting opportunities and harvest levels in Missouri, managers can be most effective by controlling hectares and condition of managed croplands, especially sunflowers. However, further work is needed to assess the relative impacts of lottery regulations and nontoxic‐shot restrictions on dove harvest. © 2011 The Wildlife Society.
Structural and Vibrational Studies of Sr2[W(CN)8]·10H2O
Authors: Daszkiewicz Marek , Marchewka Mariusz K. , Typilo Iryna , Gulay Lubomir D. , Semenyshyn Dariya
Published: May 2011

The crystal structure of distrontium octacyanotungstate decahydrate, Sr2[W(CN)8]·10H2O, was solved using X‐ray single crystal diffraction. The tungsten atom lies on a two fold axis. Eight cyanide anions create tetragonal antiprismatic coordination sphere of tungsten atom. The two edge‐sharing tetragonal antiprisms of [Sr(NC)3(OH2)5], create a dimer, [Sr2(CN)6(H2O)6(μ‐H2O)2], which lies on the inversion center. One symmetry independent water molecule is located in a void of 40 Å3. Vibrational (FT‐IR and FT‐Raman spectroscopic) behavior of main structural units is discussed. It was spectroscopically confirmed that the geometry of [W(CN)8]4– anion is slightly distorted from that corresponding to “free” anion. The number of observed bands is significantly lower than that expected for C2 point group.
Homogenization of a 1D nonlinear dynamical problem for periodic composites
Authors: Andrianov I.V. , Danishevs'kyy V.V. , Topol H. , Weichert D.
Published: May 2011

In this paper we study wave propagation through a composite material built up of a periodically repeated one‐dimensional structure of coated inclusions and matrix material by the application of the asymptotic homogenization method. We take into account geometrical nonlinearity, which is described by the Cauchy‐Green strain tensor and physical nonlinearity by the Murnaghan elastic potential. We take into account structural nonlinearity by considering the bonding between two materials to be imperfect. As a result we obtain homogenized equations for the low‐frequency range.
Venous Thromboembolism After Surgery for Benign Prostatic Hyperplasia
Authors: Bergqvist David
Published: May 2011

A systematic review has been performed on venous thromboembolism after surgery for benign prostatic hyperplasia. The risk of deep vein thrombosis is two to four times higher after open surgery than after transurethral resection. The risk after the newer transurethral methods (laser, radiofrequency, heat) is not known. Specific studies on thromboprophylaxis are few and have limited numbers of patients. Nonetheless, thromboprophylaxis (heparin) reduces the frequency of postoperative deep vein thrombosis after open surgery. Studies on patients undergoing transurethral resection are lacking. Antifibrinolytic treatment to diminish bleeding does not seem to increase the risk of thrombosis.
Outcome of Radical Resection and Postoperative Radiotherapy for Thyroid Carcinoma Showing Thymus‐like Differentiation
Authors: Sun Tuanqi , Wang Zhuoying , Wang Jian , Wu Yi , Li Duanshu , Ying Hongmei
Published: May 2011

Background

Carcinoma showing thymus‐like differentiation (CASTLE) is a rare disease that is difficult to diagnose. The aim of this study was to assess the effects of combined‐modality treatment in CASTLE patients.

Methods

We retrospectively studied patients identified between January 1, 2000 and December 31, 2009 as having CASTLE and who subsequently underwent surgery and radiotherapy or chemotherapy. Preoperative laboratory findings, ultrasonographic (US) and computed tomographic (CT) features, and fine‐needle aspiration biopsy (FNAB) specimens were evaluated.

Results

Seven patients with CASTLE were identified (four men, three women). The median age at initial diagnosis was 48 years (range 25–56 years). The five newly diagnosed patients were treated with curative surgery and postoperative radiotherapy, whereas two patients with recurrent disease were treated with salvage surgery plus radiotherapy or chemotherapy. All patients were disease‐free at a median follow‐up period of 34 months (range 12–61 months). The pattern of immunohistochemical staining was similar to that of thymic carcinoma. Specimens from all seven patients stained positively for CD5, CD117, and cytokeratin but were uniformly negative for thyroglobulin, thyroid transcription factor 1 (TTF‐1), and calcitonin.

Conclusions

Patients with CASTLE have excellent outcomes after curative resection and postoperative radiotherapy compared with patients with anaplastic thyroid carcinoma. Even patients with local recurrent disease benefited from salvage surgery with subsequent operation and/or radiotherapy. CD5 immunohistochemical staining on FNAB samples may help identify the possible entities that are part of the differential diagnosis.
The chemotactic interaction between CCL21 and its receptor, CCR7, facilitates the progression of pancreatic cancer via induction of angiogenesis and lymphangiogenesis
Authors: Zhao Bin , Cui Kai , Wang Chang‐Liang , Wang Ai‐Liang , Zhang Bo , Zhou Wu‐Yuan , Zhao Wen‐Hua , Li Sheng
Published: May 2011

Background

In this study, we report the influence of CCL21 and its receptor, CCR7, on the progression of pancreatic cancer and illuminates the correlation between the CCL21/CCR7 axis and the angiogenesis and lymphangiogenesis of pancreatic adenocarcinoma (PAC).

Methods

A total of 30 patients with pancreatic cancer was involved in the current study. The expression of CCL21 and CCR7 in cancerous tissues, paracancerous tissues and normal pancreas were investigated using real‐time PCR, Western blot and immunohistochemistry, respectively. In addition, we assessed microvessel density (MVD) and microlymphatic vessel density (MLVD) in tumor tissues using immunohistochemistry.

Results

Compared to paracancerous tissues and normal pancreas, CCL21 expression in cancerous tissues was detected at a significantly low level. In contrast, the CCR7 expression was considerably higher in cancerous tissues than in normal pancreas and paracancerous tissues. Additionally, a significant correlation between the expression pattern of the CCL21/CCR7 axis and clinicopathological features, such as lymph node metastasis, was identified. Furthermore, we found that CCL21 expression was significantly associated with MVD but not significantly associated with MLVD, while CCR7 expression was significantly associated with MLVD but not significantly associated with MVD.

Conclusions

The chemotactic interaction between CCR7 and its ligand, CCL21, may be a critical event during progression in pancreatic cancer, and its underlying mechanism may be induction of angiogenesis and lymphangiogenesis regulated by this chemotactic interaction.
Preoperative identification of intraoperative blood loss of more than 1,500 mL during elective hepatectomy
Authors: Yamamoto Yusuke , Shimada Kazuaki , Sakamoto Yoshihiro , Esaki Minoru , Nara Satoshi , Kosuge Tomoo
Published: May 2011

Background

Despite recent advances in surgical techniques, hepatectomies remain one of the most hemorrhagic procedures in abdominal surgery. It is important to identify preoperatively patients who are at high risk of suffering massive intraoperative blood loss.

Methods

The clinical records of 251 patients who underwent an elective hepatectomy for liver tumors between September 2007 and December 2009 were reviewed retrospectively. A multivariate logistic regression analysis of preoperative factors potentially influencing intraoperative blood loss was performed. We set the cut‐off value of the amount of blood loss for safe hepatectomy as less than 1,500 mL because no patients with blood loss of less than 1,500 mL received blood transfusion in this study. A scoring system to predict blood loss of more than 1,500 mL was constructed and validated in a cohort of 59 subsequent patients.

Results

Intraoperative blood loss of more than 1,500 mL was recognized in 35 of 251 patients (13.9%). Prothrombin activity < 70%, nonperipheral location of the tumor, involvement of hepatic veins, body mass index ≥ 23.0, and major hepatectomy were independently associated with intraoperative blood loss of more than 1,500 mL. The score was calculated by assigning 1 point for each of the 5 risk factors. The area under the receiver operating characteristic curve (AUC) was 0.814 (95% CI 0.731−0.898). This scoring system was highly predictive in the subsequent validation group of 59 patients (AUC = 0.839, 95% CI 0.710−0.969).

Conclusion

This predictive scoring system is considered to be useful for identifying before hepatectomy those patients with a high risk of intraoperative blood loss of more than 1,500 mL.
What is a problem?
Authors: Schmidt Jan C.
Published: May 2011

Among others, the term “problem” plays a major role in the various attempts to characterize interdisciplinarity or transdisciplinarity, as used synonymously in this paper. Interdisciplinarity (ID) is regarded as “problem solving among science, technology and society” and as “problem orientation beyond disciplinary constraints” (cf. Frodeman et al.: The Oxford Handbook of Interdisciplinarity. Oxford University Press, Oxford, 2010). The point of departure of this paper is that the discourse and practice of ID have problems with the “problem”. The objective here is to shed some light on the vague notion of “problem” in order to advocate a specific type of interdisciplinarity: problem-oriented interdisciplinarity. The outline is as follows: Taking an ex negativo approach, I will show what problem-oriented ID does not mean. Using references to well-established distinctions in philosophy of science, I will show three other types of ID that should not be placed under the umbrella term “problem-oriented ID”: object-oriented ID (“ontology”), theory-oriented ID (epistemology), and method-oriented ID (methodology). Different philosophical thought traditions can be related to these distinguishable meanings. I will then clarify the notion of “problem” by looking at three systematic elements: an undesired (initial) state, a desired (goal) state, and the barriers in getting from the one to the other. These three elements include three related kinds of knowledge: systems, target, and transformation knowledge. This paper elaborates further methodological and epistemological elements of problem-oriented ID. It concludes by stressing that problem-oriented ID is the most needed as well as the most challenging type of ID.
Item Selection in Multidimensional Computerized Adaptive Testing—Gaining Information from Different Angles
Authors: Wang Chun , Chang Hua-Hua
Published: May 2011

Over the past thirty years, obtaining diagnostic information from examinees’ item responses has become an increasingly important feature of educational and psychological testing. The objective can be achieved by sequentially selecting multidimensional items to fit the class of latent traits being assessed, and therefore Multidimensional Computerized Adaptive Testing (MCAT) is one reasonable approach to such task. This study conducts a rigorous investigation on the relationships among four promising item selection methods: D-optimality, KL information index, continuous entropy, and mutual information. Some theoretical connections among the methods are demonstrated to show how information about the unknown vector θ can be gained from different perspectives. Two simulation studies were carried out to compare the performance of the four methods. The simulation results showed that mutual information not only improved the overall estimation accuracy but also yielded the smallest conditional mean squared error in most region of θ. In the end, the overlap rates were calculated to empirically show the similarity and difference among the four methods.
Arthroscopic Arthrolysis for Arthrofibrosis of the Knee after Total Knee Replacement
Authors: Hegazy Alaa M. , Elsoufy Mohamed A.
Published: May 2011

Background

Arthrofibrosis is an uncommon but potentially debilitating complication following total knee replacement which can result in chronic pain and poor recovery of range of motion. The treatment of this condition remains difficult and controversial.

Questions/aims of study

We reviewed our results of arthroscopic arthrolysis of arthrofibrosis of the knee after total knee replacement to assess the potential for this technique to improve range of motion and provide improvement in knee function and pain as measured by the Knee Society Score (KSS).

Methods

Eight patients were treated for arthrofibrosis after total knee replacement with arthroscopic management. The patients included five females and three males. The average age was 67.4 years. Initial rehabilitation efforts, which included manipulation under anesthesia, had failed. Arthroscopic arthrolysis was performed to release fibrous bands in the suprapatellar pouch and to reestablish the medial and lateral gutters. Lateral release of the patellar retinaculum was performed. Intensive physiotherapy and continuous passive motion began immediately post-operatively. The average follow-up was 37.4 months. The KSS was used for assessment of pain and function before arthroscopy and at the latest follow-up.

Results

Six of the eight patients experienced improvement in the KSS. The average functional score showed improvement from 68 points pre-operatively to 86 at the time of final follow-up. The average pain scores improved from 30 points pre-operatively to 41 at the time of final follow-up.

Conclusions

Arthroscopic management can be beneficial for patients suffering from arthrofibrosis following total knee replacement. Pain and KSS clinical scores can markedly improve.
On the New Chinese Literature as an Interliterary Community
Authors: GÁLIK Marián
Published: May 2011

The aim of this essay is to point out the characteristic traits of the new Chinese literature as a “specific interliterary community” to some extent different from most of the “specific interliterary communities” of the world, for instance, Czech and Slovak literature, the Slavic literatures of Eastern Europe, or the literatures of the former socialist countries. Different from these and other communities of this kind, the new Chinese literature, especially after 1949, did not proceed with the interliterary process without points of friction, sometimes even with mutual attacks and mutual disrespect caused by political reasons: ideological differences, contradictory aims, neglect of human rights, democratic tendencies, and political propaganda. The interliterary process along which the new Chinese literature, or better to say “literatures,” is progressing, is here stressed together with “interliterariness,” the overstepping of one single literature and its coming into contact with one or more single literatures of the world. The interliterary community of Chinese literature within the whole set of its single literatures (from the mainland of China, Hong Kong, Macao, Taiwan and overseas Chinese literatures) presents an area where three different functions play their roles, of which at least one should be implemented: integrational, differentiating, and complementary. To understand the new Chinese literature in its relations within itself and the literatures of the world is a task to be fulfilled in the coming decades.
Cancellation of in vitro fertilization treatment cycles predicts treatment outcome in female infertility patients aged 40 years or older
Authors: Sugimoto Kouhei , Hashimoto Tomoko , Takahashi Eri , Saito Yukiyo , Haino Takayuki , Sasaki Hiroshi , Kusuhara Koji , Tanaka Tadao
Published: May 2011

Purpose

To investigate potential indicators of in vitro fertilization (IVF) treatment outcome for female infertility patients aged ≥ 40 years based on the clinical course.

Methods

We retrospectively examined results of 111 female infertility patients aged ≥ 40 years undergoing IVF treatment. We investigated the relationship between treatment cycle cancellation and the final outcome of IVF treatment in female infertility patients aged ≥ 40 years.

Results

A total of 44 pregnancies were achieved. Overall pregnancy rate per initiated treatment cycle was 12.1%, and 24 spontaneous abortions occurred (54.5%). No woman aged ≥ 45 years achieved pregnancy. No patients conceived after 10 treatment cycles while 42 (11.5%) oocyte pick‐up cycles and 120 (33.0%) embryo transfer cycles were canceled. Investigation of correlation with treatment cycle cancellation revealed that patients who experienced embryo transfer cancellation had a high spontaneous abortion rate while only a few patients who experienced oocyte pick‐up cancellation achieved pregnancy and even fewer achieved a successful outcome.

Conclusions

Our study suggests that, in addition to patient age and number of treatment cycles, cancellation of treatment cycle also provides another useful indicator for pregnancy outcome.
Estimating a Dynamic Model of Sex Selection in China
Authors: Ebenstein Avraham
Published: May 2011

High ratios of males to females in China, which have historically concerned researchers (Sen 1990), have increased in the wake of China’s one-child policy, which began in 1979. Chinese policymakers are currently attempting to correct the imbalance in the sex ratio through initiatives that provide financial compensation to parents with daughters. Other scholars have advocated a relaxation of the one-child policy to allow more parents to have a son without engaging in sex selection. In this article, I present a model of fertility choice when parents have access to a sex-selection technology and face a mandated fertility limit. By exploiting variation in fines levied in China for unsanctioned births, I estimate the relative price of a son and daughter for mothers observed in China’s census data (1982–2000). I find that a couple’s first son is worth 1.42 years of income more than a first daughter, and the premium is highest among less-educated mothers and families engaged in agriculture. Simulations indicate that a subsidy of 1 year of income to families without a son would reduce the number of “missing girls” by 67% but impose an annual cost of 1.8% of Chinese gross domestic product (GDP). Alternatively, a three-child policy would reduce the number of “missing girls” by 56% but increase the fertility rate by 35%.
Interfacial waves in two-layer exchange flows downslope of a bottom sill
Authors: FOULI HESHAM , ZHU DAVID Z.
Published: May 2011

An experimental study was conducted to examine the interfacial waves in two-layer exchange flows downslope of a bottom sill. The objective of the study was to understand the generation mechanisms of different interfacial waves and the generation conditions and development of Kelvin–Helmholtz (KH) instabilities in spatially varying flow field. During the flow regime of the steady maximal exchange, low-frequency oscillation of the density interface above the sill crest was observed, which resulted in periodic piling and releasing of the lower-layer fluid. This low-frequency oscillation led to the development of large-scale downslope waves that caused significant interfacial entrainment. The periodic time of those piling and releasing events was found to be inversely proportional to the square root of the reduced gravitational acceleration and to be related to the baroclinic forcing of the basin internal seiching. During late sub-maximal exchange, regular and frequent KH instabilities were generated at the interface down the slope at bulk Richardson number of approximately 0.07–0.21, which is considerably larger than previous theoretical predictions for parallel flows with a sharp density interface. Two different growth patterns of those KH instabilities were observed. Measurements of their initial growth rate and the wavelength were also obtained and compared to the theoretical predictions.
Tank-treading as a means of propulsion in viscous shear flows
Authors: OLLA PIERO
Published: May 2011

The use of tank-treading as a means of propulsion for microswimmers in viscous shear flows is taken into account. We discuss the possibility of a vesicle to control the drift in an external shear flow, by locally varying the bending rigidity of its membrane. By analytical calculation in the quasi-spherical limit, the stationary shape and the orientation of the tank-treading vesicle in the external flow are determined, working to lowest order in the membrane inhomogeneity. The membrane inhomogeneity acts in the shape evolution equation as an additional force term, which can be used to balance the effect of the hydrodynamic stresses, thus allowing the vesicle to assume shapes and orientations that are impossible otherwise. The vesicle shapes and orientations required for migration transverse to the flow, together with the bending rigidity profiles leading to such shapes and orientations, are determined. Considering the variations in the concentration experienced during tank-treading, a simple model is presented, in which a vesicle is able to migrate up or down the gradient of a concentration field by stiffening or softening of its membrane.
A cross-sectional study ontrans-fatty acids and risk markers of CHD among middle-aged men representing a broad range of BMI
Authors: Nielsen Birgit M. , Nielsen Marie M. , Jakobsen Marianne U. , Nielsen Carina J. , Holst Claus , Larsen Thomas M. , Bendsen Nathalie T. , Bysted Anette , Leth Torben , Hougaard David M. , Skogstrand Kristin , Astrup Arne , Sørensen Thorkild I. A. , Jess Tine
Published: May 2011

Intake oftrans-fatty acids (TFA), especially industrially produced TFA (I-TFA), has been associated with the risk of CHD through influence on serum lipid levels. Other causal pathways remain less investigated. In the present cross-sectional study of middle-aged men representing a broad range of BMI, the association between intake of TFA, I-TFA and ruminant TFA (R-TFA) and obesity-associated risk markers of CHD was assessed. The study comprised 393 Danish men (median age 49 years) with a median BMI of 28·4 kg/m2. Intake of TFA was estimated based on 7 d dietary records, whereas outcomes of interest (waist circumference, sagittal abdominal diameter, percentage of truncal fat, C-reactive protein, IL-6, blood lipids, blood pressure, HbA1c and insulin sensitivity index) were obtained through clinical examination. The associations were assessed by linear regression analysis. The median intake of total TFA among the 393 men was 1·3 g/d, covering a daily I-TFA intake of 0·4 g (10–90th percentile 0·0–1·0) and R-TFA intake of 0·9 g (10–90th percentile 0·4–1·8). Intake of these amounts of TFA showed no significant associations with abdominal fatness, inflammatory markers, blood lipids, blood pressure and insulin homeostasis. Among middle-aged men with a generally low intake of TFA, neither I-TFA nor R-TFA was significantly related to obesity-associated risk markers of CHD. The decreased average intake of I-TFA in Denmark since 1995 is suggested to effectively prevent occurrence of the adverse metabolic changes and health consequences, which have formerly been observed in relation to, especially, I-TFA intake.
The efficacy of Phaseolus vulgaris as a weight-loss supplement: a systematic review and meta-analysis of randomised clinical trials
Authors: Onakpoya Igho , Aldaas Salsabil , Terry Rohini , Ernst Edzard
Published: May 2011

A variety of dietary supplements are presently available as slimming aids, but their efficacy has not been proven. One such slimming aid is the bean extract, Phaseolusvulgaris. The aim of the present systematic review is to evaluate the evidence for or against the efficacy of P. vulgaris. Electronic and non-electronic searches were conducted to identify relevant human randomised clinical trials (RCT). Hand searches of bibliographies were also conducted. No age, time or language restrictions were imposed. The eligibility of studies was determined by two reviewers independently, and the methodological quality of the included studies was assessed. We identified eleven eligible trials, and six were included. All the included RCT had serious methodological flaws. A meta-analysis revealed a statistically non-significant difference in weight loss between P. vulgaris and placebo groups (mean difference (MD) − 1·77 kg, 95 % CI − 3·33, 0·33). A further meta-analysis revealed a statistically significant reduction in body fat favouring P. vulgaris over placebo (MD − 1·86 kg, 95 % CI − 3·39, − 0·32). Heterogeneity was evident in both analyses. The poor quality of the included RCT prevents us from drawing any firm conclusions about the effects of P. vulgaris supplementation on body weight. Larger and more rigorous trials are needed to objectively assess the effects of this herbal supplement.
Gene–PUFA interactions and obesity risk
Authors: Jourdan C. , Kloiber S. , Nieters A. , Seiler H. , Himmerich H. , Kohli M. A. , Lucae S. , Wolfram G. , Gieger C. , Wichmann H.-E. , Linseisen J.
Published: May 2011

Although there are indications for modulatory effects of PUFA on associations between SNP and obesity risk, scientific evidence in human subjects is still scarce. The present analyses investigated interaction effects between SNP in candidate genes for obesity and PUFA in erythrocyte membranes on obesity risk. Within the second Bavarian Food Consumption Survey (cross-sectional, population-based), 568 adults provided blood samples. Fatty acid composition of erythrocyte membranes was analysed by means of GC. Genotyping was performed for twenty-one genes, including cytokines, adipokines, neurotransmitters and transcription factors. In addition, plasma IL-6 concentrations were analysed. For the statistical analysis, a logistic regression model assuming additive genetic effects was chosen. About 20 % of the study participants were classified as obese (BMI ≥ 30 kg/m2). Several significant gene–PUFA interactions were found, indicating regulatory effects of PUFA by gene variants of IL-2, IL-6, IL-18, TNF receptor family member 1B and 21, leptin receptor and adiponectin on obesity risk. After stratification by genotype, the strongest effects were found for rs2069779 (IL-2) and all tested PUFA as well as for rs1800795 (IL-6) and linoleic or arachidonic acid. The obesity risk of minor allele carriers significantly decreased with increasing fatty acid content. The genetic PUFA–IL-6 interaction was also reflected in plasma IL-6 concentrations. If replicated in a prospective study with sufficient statistical power, the results would indicate a beneficial effect of high PUFA supply for a substantial proportion of the population with respect to obesity risk.
Hepcidin expression in the liver of rats fed a magnesium-deficient diet
Authors: Ishizaki Natsumi , Kotani Megumi , Funaba Masayuki , Matsui Tohru
Published: May 2011

Mg deficiency accelerates Fe accumulation in the liver, which may induce various metabolic disturbances. In the present study, we examined the gene expression of Hepcidin, a peptide hormone produced in the liver to regulate intestinal Fe absorption negatively, in Mg-deficient rats. Although liver Fe concentration was significantly higher in rats fed an Mg-deficient diet for 4 weeks than in rats fed a control diet, Hepcidin expression in the liver was comparable between the dietary groups. Previous studies revealed that Fe overload up-regulated Hepcidin expression through transcriptional activation by Fe-induced bone morphogenetic protein (Bmp) 6, a growth/differentiation factor belonging to the transforming growth factor-β family, in the liver. Mg deficiency up-regulated the expression of Bmp6 but did not affect the expression of inhibition of DNA binding 1, a sensitive Bmp-responsive gene. In addition, the expression of Bmp receptors such as activin receptor-like kinase 2 (Alk2), activin receptor type IIA (Actr2a), activin receptor type IIB (Actr2b) and Bmp type II receptor (Bmpr2) was lower in the liver of Mg-deficient rats than in that of control rats. The present study indicates that accumulation of hepatic Fe by Mg deficiency is a stimulant inducing Bmp6 expression but not Hepcidin expression by blunting Bmp signalling possibly resulting from down-regulation of the receptor expression. Unresponsive Hepcidin expression may have a role in Mg deficiency-induced changes related to increased liver Fe.
Dietary glycaemic index and glycaemic load among Australian children and adolescents
Authors: Chun Yu Louie Jimmy , Buyken Anette E. , Heyer Kristina , Flood Victoria M.
Published: May 2011

There are no published data regarding the overall dietary glycaemic index (GI) and glycaemic load (GL) of Australian children and adolescents. We therefore aim to describe the dietary GI and GL of participants of the 2007 Australian National Children's Nutrition and Physical Activity Survey (2007ANCNPAS), and to identify the main foods contributing to their GL. Children, aged 2–16 years, who provided two 24 h recalls in the 2007ANCNPAS were included. A final dataset of 4184 participants was analysed. GI of each food item was assigned using a previously published method. GL was calculated, and food groups contributing to the GL were described by age group and sex. The weighted mean dietary GI and GL of the participants were 54 (sd5) and 136 (sd44), respectively. Among the nutrients examined, Ca had the highest inverse relationship with GI (P < 0·001), while percentage energy from starch was most positively associated with GI. The association between fibre density and GI was modest, and percentage energy from sugar had an inverse relationship with GI. Daily dietary GL contributed by energy-dense and/or nutrient-poor (EDNP) items in subjects aged 14–16 years was more than doubled that of subjects aged 2–3 years. To conclude, Australian children and adolescents were having a high-GI dietary pattern characterised by high-starchy food intake and low Ca intake. A significant proportion of their dietary GL was from EDNP foods. Efforts to reduce dietary GI and GL in children and adolescents should focus on energy-dense starchy foods.
The distribution of SNP marker effects for faecal worm egg count in sheep, and the feasibility of using these markers to predict genetic merit for resistance to worm infections
Authors: KEMPER KATHRYN E. , EMERY DAVID L. , BISHOP STEPHEN C. , ODDY HUTTON , HAYES BENJAMIN J. , DOMINIK SONJA , HENSHALL JOHN M. , GODDARD MICHAEL E.
Published: May 2011

Genetic resistance to gastrointestinal worms is a complex trait of great importance in both livestock and humans. In order to gain insights into the genetic architecture of this trait, a mixed breed population of sheep was artificially infected withTrichostrongylus colubriformis(n=3326) and thenHaemonchus contortus(n=2669) to measure faecal worm egg count (WEC). The population was genotyped with the Illumina OvineSNP50 BeadChip and 48 640 single nucleotide polymorphism (SNP) markers passed the quality controls. An independent population of 316 sires of mixed breeds with accurate estimated breeding values for WEC were genotyped for the same SNP to assess the results obtained from the first population. We used principal components from the genomic relationship matrix among genotyped individuals to account for population stratification, and a novel approach to directly account for the sampling error associated with each SNP marker regression. The largest marker effects were estimated to explain an average of 0·48% (T. colubriformis) or 0·08% (H. contortus) of the phenotypic variance in WEC. These effects are small but consistent with results from other complex traits. We also demonstrated that methods which use all markers simultaneously can successfully predict genetic merit for resistance to worms, despite the small effects of individual markers. Correlations of genomic predictions with breeding values of the industry sires reached a maximum of 0·32. We estimate that effective across-breed predictions of genetic merit with multi-breed populations will require an average marker spacing of approximately 10 kbp.
Mapping Mendelian traits in asexual progeny using changes in marker allele frequency
Authors: LOGESWARAN SAYANTHAN , BARTON NICK H.
Published: May 2011

Linkage between markers and genes that affect a phenotype of interest may be determined by examining differences in marker allele frequency in the extreme progeny of a cross between two inbred lines. This strategy is usually employed when pooling is used to reduce genotyping costs. When the cross progeny are asexual, the extreme progeny may be selected by multiple generations of asexual reproduction and selection. We analyse this method of measuring phenotype in asexual progeny and examine the changes in marker allele frequency due to selection over many generations. Stochasticity in marker frequency in the selected population arises due to the finite initial population size. We derive the distribution of marker frequency as a result of selection at a single major locus, and show that in order to avoid spurious changes in marker allele frequency in the selected population, the initial population size should be in the low to mid hundreds.
Anterograde–retrograde rendezvous approach for radiation-induced complete upper oesophageal sphincter stenosis: case report and literature review
Authors: Kos M P , David E F , Mahieu H F
Published: May 2011

Background:

Strictures of the hypopharynx and oesophagus are frequently observed following (chemo)radiation. Anterograde dilatation of a complete stenosis carries a high risk of perforation. An alternative is described: a combined anterograde–retrograde approach.

Case report:

A 75-year-old man developed complete stenosis of the oesophageal inlet after primary radiotherapy for laryngeal carcinoma and full percutaneous endoscopic gastrostomy feeding. To prevent creation of a false route into the mediastinum, a dilatation wire was introduced in a retrograde fashion into the oesophagus, through the gastrostomy opening. The wire was endoscopically identified from the proximal side and then passed through a perforation created by CO2 laser. Anterograde dilatation was safely performed, and the patient returned to a normal diet. There is consensus in the literature that blind anterograde dilatation carries a high risk of perforation; therefore, an anterograde–retrograde rendezvous technique is advisable.

Conclusion:

In cases of complete obstruction of the oesophageal inlet, anterograde–retrograde dilatation represents a safe technique with which to restore enteric continuity.
Site selection ofAcanthochondria cornuta(Copepoda: Chondracanthidae) inPlatichthys flesus(Teleostei: Pleuronectidae)
Authors: CAVALEIRO F. I. , SANTOS M. J.
Published: May 2011

Acanthochondria cornuta(Copepoda: Chondracanthidae) (N=4841; prevalence: 80·0%; mean±s.d.[range] intensity: 28·8±24·0 [1–110] parasites) infected the branchial chambers of the European flounder,Platichthys flesus(L.), (N=210) according to an established spatial pattern. This was independent of host size. Higher intensities resulted, most frequently, in higher numbers of infection sites, probably due to increased intraspecific competition. Preferential infection of the ocular side was supported by the recorded abundance data and reflected, probably, the fish's bottom-dwelling behaviour. As the parasite develops from one stage into another, it seems to migrate towards different sites: the copepodites and pre-adult females occurred, mainly, in the holobranchs; the adults preferred the internal wall (non-gravid/post-gravid females; adult males) or the pseudobranchs (gravid females). The ventilating water current along with the blood supply are suggested as 2 major factors in determining parasite spatial distribution within the chamber. Parasite crowding in a restricted and narrow space of the posterior region of the internal wall was recorded frequently and resembled that previously reported for the plaice. Differences to other host-parasite systems previously studied should relate with the anatomy of the respiratory apparatus. Bigamous females are reported for the first time.
Précis of O'Keefe & Nadel'sThe hippocampus as a cognitive map
Authors: O'Keefe John , Nadel Lynn
Published: May 2011

Theories of spatial cognition are derived from many sources. Psychologists are concerned with determining the features of the mind which, in combination with external inputs, produce our spatialized experience. A review of philosophical and other approaches has convinced us that the brain must come equipped to impose a three-dimensional Euclidean framework on experience – our analysis suggests that object re-identification may require such a framework. We identify this absolute, nonegocentric, spatial framework with a specific neural system centered in the hippocampus.

A consideration of the kinds of behaviours in which such a spatial mapping system would be important is followed by an analysis of the anatomy and physiology of this system, with special emphasis on the place-coded neurons recorded in the hippocampus of freely moving rats. A tentative physiological model for the hippocampal cognitive map is proposed. A review of lesion studies, in tasks as diverse as discrimination learning, avoidance, and extinction, shows that the cognitive map notion can adequately explain much of the data.

The model is extended to humans by the assumption that spatial maps are built in one hemisphere, semantic maps in the other. The latter provide a semantic deep structure within which discourse comprehension and production can be achieved. Evidence from the study of amnesic patients, briefly reviewed, is consistent with this extension.
Modeling behavioral adaptations
Authors: Clark Colin W.
Published: May 2011

Optimization models have often been useful in attempting to understand the adaptive significance of behavioral traits. Originally such models were applied to isolated aspects of behavior, such as foraging, mating, or parental behavior. In reality, organisms live in complex, ever-changing environments, and are simultaneously concerned with many behavioral choices and their consequences. This target article describes a dynamic modeling technique that can be used to analyze behavior in a unified way. The technique has been widely used in behavioral studies of insects, fish, birds, mammals, and other organisms. The models use biologically meaningful parameters and variables, and lead to testable predictions. Limitations arise because nature's complexity always exceeds our modeling capacity.
Errata
Authors: Velmans Max
Published: May 2011

On p. 662 of the target article “Is Human Information Processing Conscious,” by Max Velmans, BBS (1991), 14(4):651–69, the phrase “electrical stimuli applied 500 msec later” (sect. 5.1, para. 3, 2nd sentence) should read “electrical stimuli applied 500 msec earlier.”
B-Afferents: A fundamental division of the nervous system mediating homeostasis?
Authors: Prechtl James C. , Powley Terry L.
Published: May 2011

The peripheral nervous system (PNS) has classically been separated into a somatic division composed of both afferent and efferent pathways and an autonomic division containing only efferents. J. N. Langley, who codified this asymmetrical plan at the beginning of the twentieth century, considered different afferents, including visceral ones, as candidates for inclusion in his concept of the “autonomic nervous system” (ANS), but he finally excluded all candidates for lack of any distinguishing histological markers. Langley's classification has been enormously influential in shaping modern ideas about both the structure and the function of the PNS. We survey recent information about the PNS and argue that many of the sensory neurons designated as “visceral” and “somatic” are in fact part of a histologically distinct group of afferents concerned primarily autonomic function. These afferents have traditionally been known as “small dark” neurons or B-neurons. In this target article we outline an association between autonomic and B-neurons based on ontogeny, cell phenotype, and functional relations, grouping them together as part of a common reflex system involved in homeostasis. This more parsimonious classification of the PNS, made possible by the identification of a group of afferents associated primarily with the ANS, avoids a number of confusions produced by the classical orientation. It may also have practical implications for an understanding of nociception, homeostatic reflexes, and the evolution of the nervous system.
Précis ofThe Emperor's New Mind: Concerning computers, minds, and the laws of physics
Authors: Penrose Roger
Published: May 2011

The emperor's new mind(hereafterEmperor) is an attempt to put forward a scientific alternative to the viewpoint of “strong AI,” according to which mental activity is merely the acting out of some algorithmic procedure. John Searle and other thinkers have likewise argued that mere calculation does not, of itself, evoke conscious mental attributes, such as understanding or intentionality, but they are still prepared to accept the action the brain, like that of any other physical object, could in principle be simulated by a computer. InEmperorI go further than this and suggest that the outward manifestations ofconscious mental activity cannot even be properly simulated by calculation. To support this view, I use various arguments to show that the results of mathematical insight, in particular, do not seem to be obtained algorithmically. The main thrust ofthis work, however, is to present an overview ofthe present state of physical understanding and to show that an important gap exists at the point where, quantum and classical physics meet, as well as to speculate on how the conscious brain might be taking advantage ofwhatever new physics is needed to fill this gap to achieve its nonalgorithmic effects.
Rebooting the bootstrap argument: Two puzzles for bootstrap theories of concept development
Authors: Rips Lance J. , Hespos Susan J.
Published: May 2011

The Origin of Concepts sets out an impressive defense of the view that children construct entirely new systems of concepts. We offer here two questions about this theory. First, why doesn't the bootstrapping process provide a pattern for translating between the old and new systems, contradicting their claimed incommensurability? Second, can the bootstrapping process properly distinguish meaning change from belief change?
Oculomotor skill supports the development of object representations
Authors: Schlesinger Matthew , Amso Dima
Published: May 2011

Are infants' initial object representations innately specified? We examine the development of perceptual completion in infants by highlighting two issues. First, perceptual completion is supported by neural mechanisms that rely on experience with the environment. Second, we present behavioral and modeling data that demonstrate how perceptual completion can emerge as a consequence of changes in visual attention and oculomotor skill.
Quinian bootstrapping or Fodorian combination? Core and constructed knowledge of number
Authors: Spelke Elizabeth S.
Published: May 2011

According to Carey (2009), humans construct new concepts by abstracting structural relations among sets of partly unspecified symbols, and then analogically mapping those symbol structures onto the target domain. Using the development of integer concepts as an example, I give reasons to doubt this account and to consider other ways in which language and symbol learning foster conceptual development.
Border crossings: Perceptual and post-perceptual object representation
Authors: Burge Tyler
Published: May 2011

Carey's claim that no object representations are perceptual rests on a faulty view of perception. To delineate origins of post-perceptual (“conceptual” or “core cognitive”) representation, we need a more accurate view of perceptual representation.
What is the narrow content of fence (and other definitionally and interpretationally primitive concepts)?
Authors: Mandelbaum Eric
Published: May 2011

It's unclear what narrow content is interpersonally shared for concepts that don't originate from core cognition yet are still definitionally and interpretationally primitive. A primary concern is that for these concepts, one cannot draw a principled distinction between inferences that are content determining and those that aren't. The lack of a principled distinction imperils an account of interpersonally shared concepts.
Infants' representations of causation
Authors: Butterfill Stephen A.
Published: May 2011

It is consistent with the evidence in The Origin of Concepts to conjecture that infants' causal representations, like their numerical representations, are not continuous with adults', so that bootstrapping is needed in both cases.