bluuebunny/crossref_metadata_2025 huggingface dataset:
Exploring the folkbiological conception of human nature
Authors: Linquist Stefan , Machery Edouard , Griffiths Paul E. , Stotz Karola
Published: January 2011

Integrating the study of human diversity into the human evolutionary sciences requires substantial revision of traditional conceptions of a shared human nature. This process may be made more difficult by entrenched, ‘folkbiological’ modes of thought. Earlier work by the authors suggests that biologically naive subjects hold an implicit theory according to which some traits are expressions of an animal's inner nature while others are imposed by its environment. In this paper, we report further studies that extend and refine our account of this aspect of folkbiology. We examine biologically naive subjects' judgments about whether traits of an animal are ‘innate’, ‘in its DNA’ or ‘part of its nature’. Subjects do not understand these three descriptions to be equivalent. Both innate and in its DNA have the connotation that the trait is species-typical. This poses an obstacle to the assimilation of the biology of polymorphic and plastic traits by biologically naive audiences. Researchers themselves may not be immune to the continuing pull of folkbiological modes of thought.
Understanding the nature of wealth and its effects on human fitness
Authors: Mulder Monique Borgerhoff , Beheim Bret A.
Published: January 2011

Studying fitness consequences of variable behavioural, physiological and cognitive traits in contemporary populations constitutes the specific contribution of human behavioural ecology to the study of human diversity. Yet, despite 30 years of evolutionary anthropological interest in the determinants of fitness, there exist few principled investigations of the diverse sources of wealth that might reveal selective forces during recent human history. To develop a more holistic understanding of how selection shapes human phenotypic traits, be these transmitted by genetic or cultural means, we expand the conventional focus on associations between socioeconomic status and fitness to three distinct types of wealth—embodied, material and relational. Using a model selection approach to the study of women's success in raising offspring in an African horticultural population (the Tanzanian Pimbwe), we find that the top performing models consistently include relational and material wealth, with embodied wealth as a less reliable predictor. Specifically, child mortality risk is increased with few household assets, parent nonresidency, child legitimacy, and one or more parents having been accused of witchcraft. The use of multiple models to test various hypotheses greatly facilitates systematic comparative analyses of human behavioural diversity in wealth accrual and investment across different kinds of societies.
Macro-evolutionary studies of cultural diversity: a review of empirical studies of cultural transmission and cultural adaptation
Authors: Mace Ruth , Jordan Fiona M.
Published: January 2011

A growing body of theoretical and empirical research has examined cultural transmission and adaptive cultural behaviour at the individual, within-group level. However, relatively few studies have tried to examine proximate transmission or test ultimate adaptive hypotheses about behavioural or cultural diversity at a between-societies macro-level. In both the history of anthropology and in present-day work, a common approach to examining adaptive behaviour at the macro-level has been through correlating various cultural traits with features of ecology. We discuss some difficulties with simple ecological associations, and then review cultural phylogenetic studies that have attempted to go beyond correlations to understand the underlying cultural evolutionary processes. We conclude with an example of a phylogenetically controlled approach to understanding proximate transmission pathways in Austronesian cultural diversity.
Evolutionary accounts of human behavioural diversity
Authors: Brown Gillian R. , Dickins Thomas E. , Sear Rebecca , Laland Kevin N.
Published: January 2011

Human beings persist in an extraordinary range of ecological settings, in the process exhibiting enormous behavioural diversity, both within and between populations. People vary in their social, mating and parental behaviour and have diverse and elaborate beliefs, traditions, norms and institutions. The aim of this theme issue is to ask whether, and how, evolutionary theory can help us to understand this diversity. In this introductory article, we provide a background to the debate surrounding how best to understand behavioural diversity using evolutionary models of human behaviour. In particular, we examine how diversity has been viewed by the main subdisciplines within the human evolutionary behavioural sciences, focusing in particular on the human behavioural ecology, evolutionary psychology and cultural evolution approaches. In addition to differences in focus and methodology, these subdisciplines have traditionally varied in the emphasis placed on human universals, ecological factors and socially learned behaviour, and on how they have addressed the issue of genetic variation. We reaffirm that evolutionary theory provides an essential framework for understanding behavioural diversity within and between human populations, but argue that greater integration between the subfields is critical to developing a satisfactory understanding of diversity.
On the number of independent cultural traits carried by individuals and populations
Authors: Lehmann Laurent , Aoki Kenichi , Feldman Marcus W.
Published: January 2011

In species subject to individual and social learning, each individual is likely to express a certain number of different cultural traits acquired during its lifetime. If the process of trait innovation and transmission reaches a steady state in the population, the number of different cultural traits carried by an individual converges to some stationary distribution. We call this the trait-number distribution. In this paper, we derive the trait-number distributions for both individuals and populations when cultural traits are independent of each other. Our results suggest that as the number of cultural traits becomes large, the trait-number distributions approach Poisson distributions so that their means characterize cultural diversity in the population. We then analyse how the mean trait number varies at both the individual and population levels as a function of various demographic features, such as population size and subdivision, and social learning rules, such as conformism and anti-conformism. Diversity at the individual and population levels, as well as at the level of cultural homogeneity within groups, depends critically on the details of population demography and the individual and social learning rules.
miR-191 regulates mouse erythroblast enucleation by down-regulating Riok3 and Mxi1
Authors: Zhang Lingbo , Flygare Johan , Wong Piu , Lim Bing , Lodish Harvey F.
Published: January 2011

Using RNA-seq technology, we found that the majority of microRNAs (miRNAs) present in CFU-E erythroid progenitors are down-regulated during terminal erythroid differentiation. Of the developmentally down-regulated miRNAs, ectopic overexpression of miR-191 blocks erythroid enucleation but has minor effects on proliferation and differentiation. We identified two erythroid-enriched and developmentally up-regulated genes, Riok3 and Mxi1, as direct targets of miR-191. Knockdown of either Riok3 or Mxi1 blocks enucleation, and either physiological overexpression of miR-191 or knockdown of Riok3 or Mxi1 blocks chromatin condensation. Thus, down-regulation of miR-191 is essential for erythroid chromatin condensation and enucleation by allowing up-regulation of Riok3 and Mxi1.
MCM-BP regulates unloading of the MCM2–7 helicase in late S phase
Authors: Nishiyama Atsuya , Frappier Lori , Méchali Marcel
Published: January 2011

Origins of DNA replication are licensed by recruiting MCM2–7 to assemble the prereplicative complex (pre-RC). How MCM2–7 is inactivated or removed from chromatin at the end of S phase is still unclear. Here, we show that MCM-BP can disassemble the MCM2–7 complex and might function as an unloader of MCM2–7 from chromatin. In Xenopus egg extracts, MCM-BP exists in a stable complex with MCM7, but is not associated with the MCM2–7 hexameric complex. MCM-BP accumulates in nuclei in late S phase, well after the loading of MCM2–7 onto chromatin. MCM-BP immunodepletion in Xenopus egg extracts inhibits replication-dependent MCM dissociation without affecting pre-RC formation and DNA replication. When excess MCM-BP is incubated with Xenopus egg extracts or immunopurified MCM2–7, it binds to MCM proteins and promotes disassembly of the MCM2–7 complex. Recombinant MCM-BP also releases MCM2–7 from isolated late-S-phase chromatin, but this activity is abolished when DNA replication is blocked. MCM-BP silencing in human cells also delays MCM dissociation in late S phase. We propose that MCM-BP plays a key role in the mechanism by which pre-RC is cleared from replicated DNA in vertebrate cells.
The Unfolded Protein Response: How Protein Folding Became a Restrictive Aspect for Innate Immunity and B Lymphocytes1
Authors: Costa C. Z. F. , da Rosa S. E. A. , de Camargo M. M.
Published: January 2011

Chaperone production is an essential step for proper folding of certain proteins. Accumulation of misfolded/unfolded proteins within the endoplasmic reticulum (ER) lumen triggers a signalling pathway named unfolded protein response (UPR). Upon activation, the UPR pathway augments transcription of ER chaperones increasing protein folding, decreases protein translation to ameliorate the ER overload, increases protein degradation, and activates the apoptotic programme if all previous measures fail. In this review, we will cover the chaperones involved in folding of proteins related to the immune response, followed by an overview of the UPR pathway. Lastly, we will discuss data from this last decade that demonstrate how the improper activation of the UPR pathway has been uncovered as a mechanism responsible for failure to mount a proper immune response, both innate and adaptive.
Leptospirosis: Aspects of Innate Immunity, Immunopathogenesis and Immune Evasion From the Complement System
Authors: Fraga T. R. , Barbosa A. S. , Isaac L.
Published: January 2011

Leptospirosis is a neglected infectious disease caused by spirochetes from the genus Leptospira. It constitutes a major public health problem in developing countries, with outcomes ranging from subclinical infections to fatal pulmonary haemorrhage and Weil′s syndrome. To successfully establish an infection, leptospires bind to extracellular matrix compounds and host cells. The interaction of leptospires with pathogen recognition receptors is a fundamental issue in leptospiral immunity as well as in immunophatology. Pathogenic but not saprophytic leptospires are able to evade the host complement system, circulate in the blood and spread into tissues. The target organs in human leptospirosis include the kidneys and the lungs. The association of an autoimmune process with these pathologies has been explored and diverse mechanisms that permit leptospires to survive in the kidneys of reservoir animals have been proposed. However, despite the intense research aimed at the development of a leptospirosis vaccine supported by the genome sequencing of Leptospira strains, there have been relatively few studies focused on leptospiral immunity. The knowledge of evasion strategies employed by pathogenic leptospires to subvert the immune system is of extreme importance as they may represent targets for the development of new treatments and prophylactic approaches in leptospirosis.
Jasmonic acid perception by COI1 involves inositol polyphosphates in Arabidopsis thaliana
Authors: Mosblech Alina , Thurow Corinna , Gatz Christiane , Feussner Ivo , Heilmann Ingo
Published: January 2011

Plant responses to wounding are part of their defense responses against insects, and are tightly regulated. The isoleucin conjugate of jasmonic acid (JA‐Ile) is a major regulatory molecule. We have previously shown that inositol polyphosphate signals are required for defense responses in Arabidopsis; however, the way in which inositol polyphosphates contribute to plant responses to wounding has so far remained unclear. Arabidopsis F‐box proteins involved in the perception of JA‐Ile (COI1) and auxin (TIR1) are structurally similar. Because TIR1 has recently been shown to contain inositol hexakisphosphate (InsP6) as a co‐factor of unknown function, here we explored the possibility that InsP6 or another inositol polyphosphate is required for COI1 function. In support of this hypothesis, COI1 variants with changes in putative inositol polyphosphate coordinating residues exhibited a reduced interaction with the COI1 target, JAZ9, in yeast two‐hybrid tests. The equivalent COI1 variants displayed a reduced capability to rescue jasmonate‐mediated root growth inhibition or silique development in Arabidopsis coi1 mutants. Yeast two‐hybrid tests using wild‐type COI1 in an ipk1Δ yeast strain exhibiting increased levels of inositol pentakisphosphate (InsP5) and reduced levels of InsP6 indicate an enhanced COI1/JAZ9 interaction. Consistent with these findings, Arabidopsis ipk1‐1 mutants, also with increased InsP5 and reduced InsP6 levels, showed increased defensive capabilities via COI1‐mediated processes, including wound‐induced gene expression, defense against caterpillars or root growth inhibition by jasmonate. The combined data from experiments using mutated COI1 variants, as well as yeast and Arabidopsis backgrounds altered in inositol polyphosphate metabolism, indicate that an inositol polyphosphate, and probably InsP5, contributes to COI1 function.
Sphingolipids involvement in plant endomembrane differentiation: the BY2 case
Authors: Aubert Anne , Marion Jessica , Boulogne Claire , Bourge Mickael , Abreu Susana , Bellec Yannick , Faure Jean‐Denis , Satiat‐Jeunemaitre Béatrice
Published: January 2011

Sphingolipids play an essential role in the functioning of the secretory pathway in eukaryotic organisms. Their importance in the functional organization of plant cells has not been studied in any detail before. The sphingolipid synthesis inhibitor fumonisin B1 (FB1), a mycotoxin acting as a specific inhibitor of ceramide synthase, was tested for its effects on cell growth, cell polarity, cell shape, cell cycle and on the ultrastructure of BY2 cells. We used cell lines expressing different GFP‐tagged markers for plant cell compartments, as well as a Golgi marker fused to the photoconvertible protein Kaede. Light and electron microscopy, combined with flow cytometry, were applied to analyse the morphodynamics and architecture of compartments of the secretory pathway. The results indicate that FB1 treatment had severe effects on cell growth and cell shape, and induced a delay in cell division processes. The cell changes were accompanied by the formation of the endoplasmic reticulum (ER)‐derived tubular aggregates (FB1‐induced compartments), together with an inhibition of cargo transport from the ER to the Golgi apparatus. A change in polar localization of the auxin transporter PIN1 was also observed, but endocytic processes were little affected. Electron microscopy studies confirmed that molecular FB1 targets were distinct from brefeldin A (BFA) targets. We propose that the reported effects of inhibition of ceramide biosynthesis reflect the importance of sphingolipids during cell growth and establishment of cell polarity in higher plant cells, notably through their contribution to the functional organization of the ER or its differentiation into distinct compartments.
Cytokinin promotes flowering of Arabidopsis via transcriptional activation of the FT paralogue TSF
Authors: D’Aloia Maria , Bonhomme Delphine , Bouché Frédéric , Tamseddak Karim , Ormenese Sandra , Torti Stefano , Coupland George , Périlleux Claire
Published: January 2011

Cytokinins are involved in many aspects of plant growth and development, and physiological evidence also indicates that they have a role in floral transition. In order to integrate these phytohormones into the current knowledge of genetically defined molecular pathways to flowering, we performed exogenous treatments of adult wild type and mutant Arabidopsis plants, and analysed the expression of candidate genes. We used a hydroponic system that enables synchronous growth and flowering of Arabidopsis, and allows the precise application of chemicals to the roots for defined periods of time. We show that the application of N6‐benzylaminopurine (BAP) promotes flowering of plants grown in non‐inductive short days. The response to cytokinin treatment does not require FLOWERING LOCUS T (FT), but activates its paralogue TWIN SISTER OF FT (TSF), as well as FD, which encodes a partner protein of TSF, and the downstream gene SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1). Treatment of selected mutants confirmed that TSF and SOC1 are necessary for the flowering response to BAP, whereas the activation cascade might partially act independently of FD. These experiments provide a mechanistic basis for the role of cytokinins in flowering, and demonstrate that the redundant genes FT and TSF are differently regulated by distinct floral‐inducing signals.
Isolation and functional characterization of an influx silicon transporter in two pumpkin cultivars contrasting in silicon accumulation
Authors: Mitani Namiki , Yamaji Naoki , Ago Yukiko , Iwasaki Kozo , Ma Jian Feng
Published: January 2011

A high accumulation of silicon (Si) is required for overcoming abiotic and biotic stresses, but the molecular mechanisms of Si uptake, especially in dicotyledonous species, is poorly understood. Herein, we report the identification of an influx transporter of Si in two Cucurbita moschata (pumpkin) cultivars greatly differing in Si accumulation, which are used for the rootstocks of bloom and bloomless Cucumis sativus (cucumber), respectively. Heterogeneous expression in both Xenopus oocytes and rice mutant defective in Si uptake showed that the influx transporter from the bloom pumpkin rootstock can transport Si, whereas that from the bloomless rootstock cannot. Analysis with site‐directed mutagenesis showed that, among the two amino acid residues differing between the two types of rootstocks, only changing a proline to a leucine at position 242 results in the loss of Si transport activity. Furthermore, all pumpkin cultivars for bloomless rootstocks tested have this mutation. The transporter is localized in all cells of the roots, and investigation of the subcellular localization with different approaches consistently showed that the influx Si transporter from the bloom pumpkin rootstock was localized at the plasma membrane, whereas the one from the bloomless rootstock was localized at the endoplasmic reticulum. Taken together, our results indicate that the difference in Si uptake between two pumpkin cultivars is probably the result of allelic variation in one amino acid residue of the Si influx transporter, which affects the subcellular localization and subsequent transport of Si from the external solution to the root cells.
The shade avoidance syndrome in Arabidopsis: a fundamental role for atypical basic helix–loop–helix proteins as transcriptional cofactors
Authors: Galstyan Anahit , Cifuentes‐Esquivel Nicolás , Bou‐Torrent Jordi , Martinez‐Garcia Jaime F.
Published: January 2011

The shade avoidance syndrome (SAS) refers to a set of plant responses aimed at anticipating eventual shading by potential competitors. The SAS is initiated after perception of nearby vegetation as a reduction in the red to far‐red ratio (R:FR) of the incoming light. Low R:FR light is perceived by the phytochromes, triggering dramatic changes in gene expression that, in seedlings, eventually result in an increased hypocotyl elongation to overgrow competitors. This response is inhibited by genes such as PHYTOCHROME RAPIDLY REGULATED 1 (PAR1), PAR2 and LONG HYPOCOTYL IN FR 1 (HFR1), which are transcriptionally induced by low R:FR. Although PAR1/PAR2 and HFR1 proteins belong to different groups of basic helix–loop–helix (bHLH) transcriptional regulators, they all lack a typical basic domain required for binding to E‐box and G‐box motifs in the promoter of target genes. By overexpressing derivatives of PAR1 and HFR1 we show that these proteins are actually transcriptional cofactors that do not need to bind DNA to directly regulate transcription. We conclude that protein–protein interactions involving the HLH domain of PAR1 and HFR1 are a fundamental aspect of the mechanism by which these proteins regulate gene expression, most likely through interaction with true transcription factors that do bind to the target genes and eventually unleash the observed SAS responses.
Arabidopsis SNARE protein SEC22 is essential for gametophyte development and maintenance of Golgi‐stack integrity
Authors: El‐Kasmi Farid , Pacher Tobias , Strompen Georg , Stierhof York‐Dieter , Müller Lena M. , Koncz Csaba , Mayer Ulrike , Jürgens Gerd
Published: January 2011

Membrane traffic contributes to plant growth and development. However, the functional significance of SNARE proteins involved in membrane fusion of the early secretory pathway has not been explored with respect to plant development. Here we analyze the Arabidopsis v‐SNARE SEC22. Loss of SEC22 function impairs gametophyte development, as indicated by reciprocal crosses between wild‐type plants and plants heterozygous for T‐DNA insertions in the SEC22 gene. sec22 mutant pollen becomes abnormal during the bicellular stage, eventually giving rise to degenerated pollen grains. Most mutant embryo sacs fail to support embryogenesis and display unfused polar nuclei in their central cell. Immunolocalization by both light and electron microscopy revealed an association of mutant‐complementing Myc‐tagged SEC22 with the central and peripheral endoplasmic reticulum (ER). Ultrastructural analysis of developing sec22 mutant pollen demonstrated Golgi fragmentation and consumption. As a consequence, the plasma membrane‐targeted syntaxin SYP124 was retained in the ER. Our results suggest that SEC22 plays an essential role in early secretory traffic between the ER and the Golgi.
The Challenge of New Daily Persistent Headache
Authors: Evans Randolph W. , Seifert Tad D.
Published: January 2011

(Headache 2011;51:145‐154)

New daily persistent headache is a rare chronic daily headache of long duration characterized by the abrupt onset of persistent headache that generally develops over less than 3 days and does not remit. While it was initially thought to be a benign, self‐limiting disorder, further research has shown that a significant percentage of patients continue to suffer for many years, often experiencing pain that is refractory to treatment. This article reviews the symptoms, pathophysiology, diagnostic criteria, diagnostic testing, treatment, and prognosis.
Health‐related quality of life and postoperative recovery in fast‐track hysterectomy
Authors: WODLIN NINNIE BORENDAL , NILSSON LENA , KJØLHEDE PREBEN
Published: January 2011

Objective. To determine whether health‐related quality of life (HRQoL) and postoperative recovery of women who undergo abdominal hysterectomy in a fast‐track program under general anesthesia (GA) differ from women who receive spinal anesthesia with intrathecal morphine (SA). Design. Secondary analysis from an open randomized controlled multicenter study. Setting. Five hospitals in south‐east Sweden. Population. One hundred and eighty women admitted for abdominal hysterectomy for benign disease were randomized; 162 completed the study, 80 with GA and 82 with SA. Methods. The HRQoL was measured preoperatively using the EuroQoL EQ‐5D and the Short‐Form‐36 health survey (SF‐36) questionnaires. The EQ‐5D was used daily for 1 week; thereafter, once weekly for 4 weeks and again 6 months after operation. The SF‐36 was completed at 5 weeks and 6 months. Dates of commencing and ending sick leave were registered. Main Outcome Measures. Changes in HRQoL; duration of sick leave. Results. The HRQoL improved significantly faster in women after SA than after GA. Sick leave was significantly shorter after SA than after GA (median 22.5 vs. 28 days). Recovery of HRQoL and duration of sick leave were negatively influenced by postoperative complications. In particular, the mental component of HRQoL was negatively affected by minor complications, even 6 months after the operation. Conclusions. Spinal anesthesia with intrathecal morphine provided substantial advantages in fast‐track abdominal hysterectomy for benign gynecological disorders by providing faster recovery and shorter sick leave compared with general anesthesia.
Mode of anesthesia and postoperative symptoms following abdominal hysterectomy in a fast‐track setting
Authors: WODLIN NINNIE BORENDAL , NILSSON LENA , ÅRESTEDT KRISTOFER , KJØLHEDE PREBEN ,   for the ‘GASPI’ Study Group
Published: January 2011

Objective. To determine whether postoperative symptoms differ between women who undergo abdominal benign hysterectomy in a fast‐track model under general anesthesia or spinal anesthesia with intrathecal morphine. Design. Secondary analysis from a randomized, open, multicenter study. Setting. Five hospitals in south‐east Sweden. Population. One‐hundred and eighty women scheduled for benign hysterectomy were randomized; 162 completed the study; 82 were allocated to spinal and 80 to general anesthesia. Methods. The Swedish Postoperative Symptoms Questionnaire, completed daily for 1 week and thereafter once a week until 5 weeks postoperatively. Main Outcome Measures. Occurrence, intensity and duration of postoperative symptoms. Results. Women who had hysterectomy under spinal anesthesia with intrathecal morphine experienced significantly less discomfort postoperatively compared with those who had the operation under general anesthesia. Spinal anesthesia reduced the need for opioids postoperatively. The most common symptoms were pain, nausea and vomiting, itching, drowsiness and fatigue. Abdominal pain, drowsiness and fatigue occurred significantly less often and with lower intensity among the spinal anesthesia group. Although postoperative nausea and vomiting was reported equally in the two groups, vomiting episodes were reported significantly more often during the first day after surgery in the spinal anesthesia group. Spinal anesthesia was associated with a higher prevalence of postoperative itching. Conclusions. Spinal anesthesia with intrathecal morphine carries advantages regarding postoperative symptoms and recovery following fast‐track abdominal hysterectomy.
Expression of Concern: Intrauterine insemination versus timed intercourse with clomiphene citrate in polycystic ovary syndrome: a randomized controlled trial
Authors: ABU HASHIM HATEM , OMBAR OSAMA , ABD ELAAL IBRAHIM
Published: January 2011

Objective. To compare the efficacy of intrauterine insemination vs. timed intercourse with clomiphene citrate as a first‐line treatment for anovulatory infertility associated with polycystic ovary syndrome. Design. A randomized controlled trial following the CONSORT criteria. Setting. A university hospital and a private practice setting. Patients. 188 women (525 cycles) with polycystic ovary syndrome. Main outcome measures. Women received three consecutive cycles of ovulation induction with clomiphene citrate and intrauterine insemination (n=93, 259 cycles) or three consecutive cycles of clomiphene citrate with timed intercourse (n=95, 266 cycles). Outcome measures. Clinical pregnancy rate per cycle, number of growing and mature follicles, serum estradiol, endometrial thickness at the hCG day, serum progesterone, ovulation, miscarriage and live birth rates. Results. There were no differences between the two groups regarding the clinical pregnancy rate per cycle or per woman (8.49 vs. 7.89% and 23.6 vs. 22.1%; p=0.26 and p=0.33, respectively). Two twin pregnancies occurred in each group. Miscarriage and live birth rates were comparable (18.1 vs. 19% and 19.35 vs. 17.89%; p=0.31 and p=0.33, respectively). No ectopic, higher‐order pregnancies or cases of ovarian hyperstimulation syndrome occurred. No differences were found regarding the number of follicles, serum progesterone, ovulation rates, estradiol levels or endometrial thickness at the hCG day (7.7±0.4 vs. 7.5±0.6mm; p=0.54). Conclusions. Ovulation induction with clomiphene citrate and timed intercourse is as effective as that with intrauterine insemination for achieving pregnancy in polycystic ovary syndrome and could represent the initial treatment option, being less invasive and less expensive than intrauterine insemination.
Identification of the N‐terminal region of TjZNT2, a Zrt/Irt‐like protein family metal transporter, as a novel functional region involved in metal ion selectivity
Authors: Nishida Sho , Morinaga Yasuhiro , Obata Hitoshi , Mizuno Takafumi
Published: January 2011

The Zrt/Irt‐like protein (ZIP) family of transporter proteins is involved in the uptake of essential metal elements in plants. Two homologous ZIP genes from Thlaspi japonicum, TjZNT1 and TjZNT2, encode products that share high amino acid sequence similarity except at the N‐terminus and the cytoplasmic loop between transmembrane domains III and IV, and that have been shown to be Zn2+ and Mn2+ transporters, respectively. To identify the region that determines the ion selectivity of these transporters, we constructed a series of TjZNT1 and TjZNT2 chimeric genes and assayed for the Zn2+ uptake of yeast cells expressing them. As a result, the extracellular N‐terminal ends were identified as regions involved in Zn2+ selectivity. TjZNT2 possesses a 36 amino acid hydrophilic extension at its N‐terminus that is absent in native TjZNT1, and a mutant TjZNT2 lacking the N‐terminal extension was shown to possess Zn2+ uptake activity. This suggests that the extended N‐terminal region inhibits Zn2+ transport by TjZNT2. Further studies showed that it is the first 25 amino acid region of the N‐terminus that is important for the inhibition of Zn2+ transport. Furthermore, the N‐terminal truncated TjZNT2 lacked Mn2+ uptake activity. These findings suggest that the N‐terminal region is a novel substrate selector in the ZIP family of transporters.
Field Study of Enhanced TCE Reductive Dechlorination by a Full‐Scale Whey PRB
Authors: Semkiw Elizabeth S. , Barcelona Michael J.
Published: January 2011

This study evaluates the efficiency of a full‐scale, 81 m‐wide permeable reactive barrier (PRB) configured by injection of dairy whey in the downgradient region of a contaminant source zone to enhance the in situ biodegradation of high concentrations (102 to 103μg/L) of chlorinated ethenes (CEs). Ten biannual whey injections were completed in a 3.5‐year pilot phase and 1.5‐year operational phase. Improved and sustained dechlorination was observed at extraction/injection and downgradient wells in the fully‐operational phase, when dried whey masses were increased from 13.6 kg to 230–360 kg, whey slurry volumes were increased from 2300 L to 307,000–480,000 L, and extraction/injection well loops were employed for the application of whey. At extraction/injection wells, CEs decreased to low (≤10 μg/L) or undetectable levels. At downgradient wells, average trichloroethene concentrations decreased, by as much as 100% (from ≤384.2 during the pilot phase to ≤102.6 μg/L during the operational phase), while average cis‐dichloroethene concentrations decreased by as much as 57.5% (from ≤6466.1 to ≤4912.2 μg/L). Downgradient vinyl chloride averages either increased by as much as 63.8% (from ≤859.6 to ≤1407.9 μg/L) or decreased by 64.0% (from 1375.4 to 880 μg/L). Downgradient ethene + ethane averages increased by as much as 73.2% (from ≤1145.3 to ≤1347.1 μg/L). On the basis of the 2008 average market price, the estimated material cost of whey is $1.96/kg organic carbon or, for the configuration of an 81 m PRB by biannual application of 300 kg whey, $325/year. Carbon substrate cost comparisons and implications for efficient in situ treatment design are discussed.
Mao's Legacy Revisited: Its Lasting Impact on China and Post‐Mao Era Reform
Authors: Wei C. X. George
Published: January 2011

Most observers hold a positive view of China's reform since 1978 but are critical of the policies of the era of Mao Zedong, ignoring the inseparable connections between the two. This article argues that the post‐Mao era reform represents both continuity and discontinuity with the immediate past, and a complex mingling of Mao's legacy with new initiatives. The origins of many reform policies, as well as their accomplishments, could be traced back to the Mao era. They were often conditioned by, benefited from, or were built upon the outcomes of Mao's policies. These included the decisions to normalize China's relations with the United States and develop friendship with Third World countries, efforts to decentralize economic power and industrialize China without urbanization, and the move to defeat “capitalist roaders” but call Deng Xiaoping back to office. Overall, the turn toward capitalism of China has proven Mao's foresight, validated his concerns, and may be evidence of the lasting utility of Maoism.
Social Assistance in China, 1993–2002: Institutions, Feedback, and Policy Actors in the Chinese Policy Process
Authors: Hammond Daniel R.
Published: January 2011

From 1993 to 2002, the emergence of the urban resident Minimum Livelihood Guarantee (MLG) system saw a major reconfiguration and expansion of social assistance in the People's Republic of China. The development of the MLG has been a complex process. The initial emergence and design of the MLG reflect space in the Chinese state for innovations and feedback in the social assistance agenda. The expansion and development of the MLG can be explained by the interventions of key policy actors. These actors pushed the MLG for a variety of different reasons. The resources available to these actors and the outcomes of their interventions were a reflection of their institutional position in the bureaucracy. Contributing to existing studies of Chinese social policy reform, this article argues that the emergence, design, and development of the policy reflects institutional space, constraints, and feedback in the Chinese policy process.
Effect of Trade Unions on Industrial Labor Income in China
Authors: Zhang Yuan , Chen Jianqi , Wong Prins
Published: January 2011

This empirical study shows that trade unions in China do not play a significant role in affecting industrial labor income. Inactive trade unions, moreover, contribute to the deterioration of income inequality because of the existence of administrative monopoly power. China's dual market structure (i.e., the coexistence of an administrative monopoly sector and nonadministrative monopoly sector), as well as the trade unions' administrativization and bureaucratization, are main reasons that trade unions do not effectively improve China's income distribution problem. Thus, in order to optimize the structure of income distribution, trade unions in China should start a reform of de‐administrativization, reconstruction of the function of workers' rights protection, and strengthening the independence of the grassroots trade union organizations.
Multiple-Criteria Kinematic Optimization for the Design of Spherical Serial Mechanisms Using Genetic Algorithms
Authors: Zhang Xiaoli , Nelson Carl A.
Published: January 2011

A new kinematic design methodology is presented for optimization of spherical serial mechanisms. First, a new index, combining global manipulability and the uniformity of manipulability over the workspace, is presented to improve the synthesis results. This method integrates multiple criteria (workspace size, the new manipulability index, and mechanism size) linearly in one objective function. All these criteria are optimized simultaneously to lead to a solution with better performance. By changing the priorities of each criterion, different sets of desirable kinematic performance can be expressed. An adaptation of the method using a multiobjective Pareto front is also illustrated. The optimization result for a spherical bevel-geared mechanism using a genetic algorithm demonstrated that the proposed method effectively improves the quality of the optimum solution and provides insight into the workings of the mechanism. In addition, this flexible and adaptable methodology also presents a general optimization approach for linkage synthesis.
Formation of pyrite (FeS2) thin films by thermal sulfurization of dc magnetron sputtered iron
Authors: Soukup R. J. , Prabukanthan P. , Ianno N. J. , Sarkar A. , Kamler C. A. , Sekora D. G.
Published: January 2011

Iron films deposited by direct current magnetron sputtering onto glass substrates were converted into FeS2 films by thermal sulfurization. Experiments were carried out to optimize the sulfurization process, and the formation of FeS2 thin films was investigated under different annealing temperatures and times. High quality FeS2 films were fabricated using this process, and single phase pyrite films were obtained after sulfurization in a sulfur and nitrogen atmosphere at 450 °C for 1 h. Film crystallinity and phase identification were determined by using x-ray diffraction. The cubic phase pyrite films prepared were p-type, and scanning electron microscopy studies exhibited a homogeneous surface of pyrite. The authors have found that the best Ohmic contact for their pyrite thin films, using inexpensive metals, was Ni. The following were chosen for the study: Al, Mo, Fe, and Ni, and the one that led to the lowest resistance, 333 Ω, was Ni.
Flow of binary gas mixtures through small sampling orifices
Authors: Johnsen Rainer , Chatterjee B. K.
Published: January 2011

Species-dependent density changes in binary gas mixtures flowing through a small thin orifice (thickness ∼10% of diameter) have been studied experimentally using an ion drift tube, covering a limited range of the transition regime from molecular to hydrodynamic flow. The observed density changes are found to depend strongly on the mass ratio of the two flowing gases. A semiempirical formula that estimates the density changes has been derived by fitting the experimental data.
Rolling contact fatigue in high vacuum using ion plated nickel-copper-silver solid lubrication
Authors: Danyluk Mike , Dhingra Anoop
Published: January 2011

Ion plated, nickel-copper-silver coated steel ball bearings that were tested in rolling contact fatigue (RCF) experiments in high vacuum are presented in this article. ANSI T5 ball bearings were coated with approximately 10 nm of nickel-copper followed by 100 nm of silver using a dc ion plating process. The balls were then tested for RCF in vacuum in the 10−7 Torr range at 130 Hz rotational speed and at 4.1 GPa Hertzian contact stress. The significance of this work is in the extension of RCF testing to an ultrahigh vacuum (UHV) application using silver as a lubricant instead of oil. The effects of pressure and voltage on the ion plating process were also investigated using scanning electron microscopy and RCF life testing in UHV. Test results with a ball size of 5/16 in. in UHV show that deposition at voltages greater than 2.5 kV shortens the RCF life and introduces a unique failure mode. Voltage and pressure fluctuations during the deposition process result in significant thickness monitor measurement errors as well. A regulator control scheme that minimizes the process pressure overshoot is also simulated.
Correlation of plasma characteristics to etch rate and via sidewall angle in a deep reactive ion etch system using Langmuir probe and optical emission spectroscopy
Authors: Koirala S. P. , Awaah I. , Burkett S. L. , Gordon M. H.
Published: January 2011

A Langmuir probe and optical emission spectroscopy were used in a deep reactive ion etch system to correlate plasma parameters (atomic fluorine and argon emission, electron density, ion density, and electron average energy) with the etch rate and via sidewall angle. All data were obtained for coil powers ranging from 200 to 800 W, platen powers ranging from 7 to 16 W, and pressure ranging from 3.8 to 62 mTorr with constant SF6 and Ar flow rates of 112 and 18 SCCM (SCCM denotes cubic centimeter per minute at STP), respectively. Results indicate that there is a correlation with etch rate for all plasma parameters except for argon emission. For argon emission, the etch rate exhibits a double-valued relation where the etch rate can either increase or decrease with increasing argon emission intensity due to changes in pressure which affect the energy coupling efficiency. As expected, the etch rate increases for measured increases in fluorine emission, electron density, and ion density. The etch rate, however, decreases with increasing average electron energy due to collision processes. In contrast, no correlation is observed between any of the measured plasma parameters with sidewall angle. The last result is consistent with the idea that sidewall angle is primarily controlled by the passivation cycle as opposed to the etching cycle, where all the authors’ data were obtained.
EFFECTS OF COUPLING DELAYS ON SYNCHRONIZATION IN LUR'E COMPLEX DYNAMICAL NETWORKS
Authors: DING KE , HAN QING-LONG
Published: January 2011

This paper investigates the effects of coupling delays on synchronization in Lur'e complex dynamical networks. Every identical node in the network can be represented as a Lur'e system. Based on Lyapunov–Krasovskii functionals and Lur'e–Postnikov Lyapunov functionals, some delay-dependant synchronization criteria are derived by employing a delay decomposition approach. A Lur'e complex dynamical network with Chua's circuit nodes and one numerical example are given to illustrate the effectiveness of the synchronization criteria.
EXAMPLES AS INTERACTION: ON HUMANS TEACHING A COMPUTER TO PLAY A GAME
Authors: KALLES DIMITRIS , FYKOURAS ILIAS
Published: January 2011

This paper reviews an experiment in human-computer interaction, where interaction takes place when humans attempt to teach a computer to play a strategy board game. We show that while individually learned models can be shown to improve the playing performance of the computer, their straightforward composition results in diluting what was earlier learned. This observation suggests that interaction cannot be easily distributed when one hopes to harness multiple human experts to develop a quality computer player. This is related to similar approaches in robot task learning and to classic approaches to human learning and reinforces the need to develop tools that facilitate the mix of human-based tuition and computer self-learning.
δ MESON EFFECTS ON NEUTRON STARS IN THE MODIFIED QUARK–MESON COUPLING MODEL
Authors: NIU ZHONG-MING , GAO CHUN-YUAN
Published: January 2011

The properties of neutron stars are investigated by including δ meson field in the modified quark–meson coupling model. It is found that δ meson has opposite effects on hadronic matter with or without hyperons: it softens the EOSs of hadronic matter with hyperons, while it stiffens the EOSs of pure nucleonic matter. Moreover, by replacing the isovector mesons with the contact scalar–isovector interaction, a considerable change of proton fraction is observed. It is shown that the contact scalar–isovector interaction provides an approach to satisfy the constraint of Direct Urca critical star masses. However, the inclusion of δ meson increases the proton fraction, consequently it decreases the M DU which departs farther from the Direct Urca constraint. Furthermore, the inclusion of δ meson field can increase the maximum mass of neutron star and enlarge the corresponding radius, while these quantities are decreased when the contact scalar–isovector interaction is included.
STUDIES OF 44Ti AND 48Cr NUCLEI WITHIN VARIATIONAL MEAN FIELD THEORY
Authors: ROY PRIANKA , DHIMAN SHASHI K.
Published: January 2011

We have studied the nuclear structure properties of high angular momentum states in N = Z, 44 Ti , and 48 Cr nuclei by using Hartree–Fock–Bogoliubov (HFB) method with variation after angular momentum projection (VAP-HFB) technique. Effect of Kuo–Brown "KB" and its modified effective interactions has been studied using four sets of single-particle energies (SPEs) on rotational bands of these nuclei. It is seen that the HFB theory with projected wave functions by employing the VAP method describes well the overall trends of the experimental yrast level spectrum and the transition probabilities in these nuclei. The backbending of the 48 Cr nucleus has been well reproduced by the present VAP-HFB calculations with the original "KB" effective interaction at J = 12ℏ. The modified effective interaction also gives backbending for 48 Cr but at J = 10ℏ. The shape change associated with backbending effect in 48 Cr is due to the large decrease in B(E2↓) values beyond J = 12ℏ state.
MODELING TREND AND TIME-VARYING VARIANCE OF HEART BEAT RR INTERVALS DURING STRESS TEST
Authors: CAMMAROTA CAMILLO , CURIONE MARIO
Published: January 2011

The heart beat RR intervals extracted from the electrocardiogram recorded during the stress test show a non stationary profile consisting of a decreasing trend during the exercise phase, an increasing trend during the recovery and a global minimum (acme). In addition this time series exhibits a time-varying variance. We decompose the series into a deterministic trend and random fluctuation. The trend is obtained as an exponential fit of the data; the fluctuation is modeled as a mean reverting process driven by the trend, in which the random innovation has a time-varying variance. Data analysis, performed on ambulatory recorded electrocardiograms of 10 healthy subjects, shows that the model describes correctly the data series on a scale of at least 300 beats.
PATTERNS OF HYDROPHOBICITY FOUND IN THE FIRST AND SECOND TRANSMEMBRANE DOMAINS OF SOLUTE TRANSPORTERS SUGGEST A POSSIBLE ROLE IN NASCENT PROTEIN ANCHORING AND ORGANIZATION
Authors: HODGKINSON STEVE , KASCHKA WOLFGANG P.
Published: January 2011

Solute transporters (STs) are an important subgroup of integral membrane proteins that facilitate the translocation of a diverse range of solutes such as sugars, amino acids, and neurotransmitters across cell membranes. Sequence analysis indicates that STs possess multiple stretches of hydrophobic-rich amino acids that are organized into the transmembrane domains (TMDs) of the functional protein, but exactly how the correct spatial arrangement of these domains is achieved remains a challenging problem. We hypothesized that perhaps differences in interdomain hydrophobicity might play some role in this process. To test this hypothesis, we generated a heptadic model of the alpha helix and mapped the average hydrophobicities (coaxial) and hydrophobic moments (radial) of 108 TMDs found in 9 different human ST proteins. Our results, taken together with earlier work from other groups, suggest that spatial patterns of hydrophobicity found in TMDs 1 and 2 are consistent with a role for these domains in the initial anchoring of the nascent ST protein to the endoplasmic reticulum (ER), as it emerges from the ribosome complex and perhaps in the subsequent spatial organisation of STs.
COMPUTATIONAL CHALLENGES OF TUMOR SPHEROID MODELING
Authors: CHIGNOLA ROBERTO , FABBRO ALESSIO DEL , FARINA MARCELLO , MILOTTI EDOARDO
Published: January 2011

The speed and the versatility of today's computers open up new opportunities to simulate complex biological systems. Here we review a computational approach recently proposed by us to model large tumor cell populations and spheroids, and we put forward general considerations that apply to any fine-grained numerical model of tumors. We discuss ways to bypass computational limitations and discuss our incremental approach, where each step is validated by experimental observations on a quantitative basis. We present a few results on the growth of tumor cells in closed and open environments and of tumor spheroids. This study suggests new ways to explore the initial growth phase of solid tumors and to optimize antitumor treatments.