bluuebunny/crossref_metadata_2025 huggingface dataset:
Lack of variant specific CD8+ T-cell response against mutant and pre-existing variants leads to outgrowth of particular clones in acute hepatitis C
Authors: Ulsenheimer Axel , Paranhos-Baccalà Gláucia , Komurian-Pradel Florence , Raziorrouh Bijan , Kurktschiev Peter , Diepolder Helmut M , Zachoval Reinhart , Spannagl Michael , Jung Maria-Christina , Gruener Norbert H
Published: September 2013

Background

CTL escape mutations have been described during acute hepatitis C in patients who developed chronic disease later on. Our aim was to investigate the mutual relationship between HCV specific CD8+ T cells and evolution of the viral sequence during early acute HCV infection.

Results

We sequenced multiple clones of NS3 1406 epitope in 4 HLA-A*02 patients with acute hepatitis C genotype 1b infection. Pentamers specific for the variants were used to monitor the corresponding CD8+ T cell response. We observed outgrowth of mutations, which induced only a weak and thus potentially insufficient CD8+ T cell response. In one patient we observed outgrowth of variant epitopes with similarities to a different genotype rather than de novo mutations most probably due to a lack of responsiveness to these likely pre-existing variants. We could show that in acute hepatitis C CTL escape mutations occur much earlier than demonstrated in previous studies.

Conclusions

The adaption of the virus to a new host is characterized by a high and rapid variability in epitopes under CD8+ T cell immune pressure. This adaption takes place during the very early phase of acute infection and strikingly some sequences were reduced below the limit of detection at some time points but were detected at high frequency again at later time points. Independent of the observed variability, HCV-specific CD8+ T cell responses decline and no adaption to different or new antigens during the course of infection could be detected.
Manipulating the sleeping beauty mutase operon for the production of 1-propanol in engineered Escherichia coli
Authors: Srirangan Kajan , Akawi Lamees , Liu Xuejia , Westbrook Adam , Blondeel Eric JM , Aucoin Marc G , Moo-Young Murray , Chou C Perry
Published: September 2013

Background

While most resources in biofuels were directed towards implementing bioethanol programs, 1-propanol has recently received attention as a promising alternative biofuel. Nevertheless, no microorganism has been identified as a natural 1-propanol producer. In this study, we manipulated a novel metabolic pathway for the synthesis of 1-propanol in the genetically tractable bacterium Escherichia coli.

Results

E. coli strains capable of producing heterologous 1-propanol were engineered by extending the dissimilation of succinate via propionyl-CoA. This was accomplished by expressing a selection of key genes, i.e. (1) three native genes in the sleeping beauty mutase (Sbm) operon, i.e. sbm-ygfD-ygfG from E. coli, (2) the genes encoding bifunctional aldehyde/alcohol dehydrogenases (ADHs) from several microbial sources, and (3) the sucCD gene encoding succinyl-CoA synthetase from E. coli. Using the developed whole-cell biocatalyst under anaerobic conditions, production titers up to 150 mg/L of 1-propanol were obtained. In addition, several genetic and chemical effects on the production of 1-propanol were investigated, indicating that certain host-gene deletions could abolish 1-propanol production as well as that the expression of a putative protein kinase (encoded by ygfD/argK) was crucial for 1-propanol biosynthesis.

Conclusions

The study has provided a novel route for 1-propanol production in E. coli, which is subjected to further improvement by identifying limiting conversion steps, shifting major carbon flux to the productive pathway, and optimizing gene expression and culture conditions.
Analysis of the microRNA transcriptome and expression of different isomiRs in human peripheral blood mononuclear cells
Authors: Vaz Candida , Ahmad Hafiz M , Bharti Richa , Pandey Priyatama , Kumar Lalit , Kulshreshtha Ritu , Bhattacharya Alok
Published: September 2013

Background

MicroRNAs (miRNAs) have been recognized as one of the key regulatory non-coding RNAs that are involved in a number of basic cellular processes. miRNA expression profiling helps to identify miRNAs that could serve as biomarkers. Next generation sequencing (NGS) platforms provide the most effective way of miRNA profiling, particularly as expression of different isoforms of miRNA (IsomiRs) can be estimated by NGS. Therefore, it is now possible to discern the overall complexity of miRNA populations that participate in gene regulatory networks. It is thus important to consider different isoforms of miRNA as part of total profiling in order to understand all aspects of the biology of miRNAs.

Results

Here next generation sequencing data of small RNAs derived from normal peripheral blood mononuclear cells (PBMC) and Chronic myeloid leukemia (CML) patients has been used to generate miRNA profiles using a computation pipeline which can identify isomiRs that are natural variants of mature miRNAs. IsomiR profiles have been generated for all the 5p and 3p miRNAs (previously known as major mature miRNA and minor or miRNA*) and the data has been presented as a composite total miRNA transcriptome. The results indicated that the most abundant isomiR sequence of about 68% miRNAs, did not match the reference miRNA sequence as entered in the miRBase and that there is a definite pattern in relative concentration of different isomiRs derived from same precursors. Finally, a total of 17 potential novel miRNA sequences were identified suggesting that there are still some new miRNAs yet to be discovered.

Conclusions

Inclusion of different isoforms provides a detailed miRnome of a cell type or tissues. Availability of miRnome will be useful for finding biomarkers of different cell types and disease states. Our results also indicate that the relative expression levels of different isoforms of a miRNA are likely to be dynamic and may change with respect to changes in the cell or differentiation status.
Ultra low concentration deltamethrin loaded patch development and evaluation of its repellency against dengue vector Aedes (S) albopictus
Authors: Chattopadhyay Pronobesh , Dhiman Sunil , Devi Kangujam Adiya , Banerjee Subham , Rabha Bipul , Chaurasia Ashwani , Veer Vijay
Published: September 2013

Background

Mosquito repellents and emanators confer protection against mosquito bites through spatial action of emanated vapours which are released into the adjoining environment. Synthetic insecticides released into the environment in ultra low volume vapour phase deter the mosquitoes from biting humans in a protected space.

Methods

Formulation patches were prepared using the solvent evaporation method over a backing membrane and using Dibutylphthalate (DBT) as a plasticizer. The effect of formulation variables on the deltamethrin release from the patch matrices were studied under accelerated conditions, whereas, HPLC was used for quantitative estimation of deltamethrin. The prepared patch formulations were subjected to physicochemical studies, such as, deltamethrin content, thickness, weight variation, percent moisture content, moisture uptake, surface area and surface pH determination. Deltamethrin-polymer interaction and compatibility was ascertained using DSC and FT-IR, while surface morphology and deltamethrin distribution in the patch were studied using SEM technique. Repellent activity of the patch formulations was evaluated against Ae. albopictus mosquitoes.

Results

Blends of polymeric combinations of polyvinylpyrrolidone (PVP) and ethyl-cellulose (EC) with admixture of deltamethrin provided prolonged repellent activity against Ae. albopictus mosquitoes. Physicochemical characterisation indicated the suitability of deltamethrin patch formulation with the polymeric combinations of PVP and EC. Patches were very effective against laboratory reared Ae. albopictus mosquitoes. No significant difference was observed between the performance of test patches and commercially available repellent cream Mosqshield®.

Conclusion

Deltamethrin loaded patches provided effective repellency against Ae. albopictus mosquitoes. The study emphasised that deltamethrin released to the environment in low concentration could be an excellent spatial repellent against hematophagous mosquitoes.
Candidate microRNA biomarkers of pancreatic ductal adenocarcinoma: meta-analysis, experimental validation and clinical significance
Authors: Ma Ming-Zhe , Kong Xiang , Weng Ming-Zhe , Cheng Kun , Gong Wei , Quan Zhi-Wei , Peng Cheng-Hong
Published: September 2013

Background

The diagnostic and prognostic value of microRNA (miRNA) expression aberrations in pancreatic ductal adenocarcinoma (PDAC) has been studied extensively in recent years. However, differences in measurement platforms and lab protocols as well as small sample sizes can render gene expression levels incomparable.

Methods

A comprehensive meta-review of published studies in PDAC that compared the miRNA expression profiles of PDAC tissues and paired neighbouring noncancerous pancreatic tissues was performed to determine candidate miRNA biomarkers for PDAC. Both a miRNA vote-counting strategy and a recently published Robust Rank Aggregation method were employed. In this review, a total of 538 tumour and 206 noncancerous control samples were included.

Results

We identified a statistically significant miRNA meta-signature of seven up- and three down-regulated miRNAs. The experimental validation results showed that the miRNA expression levels were in accordance with the meta-signature. The results from the vote-counting strategy were consistent with those from the Robust Rank Aggregation method. The experimental validation confirmed that the statistically unique profiles identified by the meta-review approach could discriminate PDAC tissues from paired nonmalignant pancreatic tissues. In a cohort of 70 patients, the high expression of miR-21 (p=0.018, HR=2.610; 95% CI=1.179-5.777) and miR-31 (p=0.039, HR=2.735; 95% CI=1.317-6.426), the low expression of miR-375 (p=0.022, HR=2.337; 95% CI=1.431-5.066) were associated with poor overall survival following resection, independent of clinical covariates.

Conclusions

The identified miRNAs may be used to develop a panel of diagnostic and prognostic biomarkers for PDAC with sufficient sensitivity and specificity for use in a clinical setting.
p66Shc regulates vesicle-mediated secretion in mast cells by affecting F-actin dynamics
Authors: Masi Giulia , Mercati David , Vannuccini Elisa , Paccagnini Eugenio , Riparbelli Maria Giovanna , Lupetti Pietro , Pelicci Pier Giuseppe , Baldari Cosima T , Ulivieri Cristina
Published: September 2013

The extracellular vesicular compartment has emerged as a novel system of intercellular communication; however, the mechanisms involved in membrane vesicle biogenesis and secretion are as yet unclear. Among immune cells releasing membrane vesicles—mast cells that reside near tissues exposed to the environment—are master modulators of immune responses. Here, we have addressed the role of p66Shc, a novel regulator of mast cell activation and homeostasis, in the dynamic reorganization of the actin cytoskeleton that is associated with morphological changes during secretion. We show that p66Shc is recruited as a complex with the lipid phosphatase SHIP1 to the F-actin skeleton and impairs antigen-dependent cortical F-actin disassembly and membrane ruffling through the inhibition of Vav and paxillin phosphorylation. We also show that in addition to acting as a negative regulator of antigen-dependent mast cell degranulation, p66Shc limits the basal release of granule contents by inhibiting microvesicle budding from the plasma membrane and piecemeal degranulation. These findings identify p66Shc as a critical regulator of actin dynamics in mast cells, providing a basis for understanding the molecular mechanisms involved in vesicle-mediated secretion in these cells.
Switchable Aggregation Phenomena of DNA-conjugated Poly(N-isopropylacrylamide) Driven by Transformation between ssDNA and dsDNA with Control of DNA Charges and Flexibility
Authors: Sugawara Yuuki , Tamaki Takanori , Ohashi Hidenori , Yamaguchi Takeo
Published: September 2013

It is possible to switch between the different aggregation phenomena of deoxyribonucleic acid (DNA)-conjugated poly(N-isopropylacrylamide) (PNIPAM) by controlling the balance of DNA charges and flexibility. The shift in the balance between DNA charges and flexibility occurs by changing the salt concentration in polymer solutions and the DNA fraction in polymer chains. Single-stranded DNA (ssDNA)-conjugated PNIPAM was more aggregated than double-stranded (dsDNA) when DNA charges are predominant. In contrast, dsDNA-conjugated PNIPAM was more aggregated than ssDNA when flexibility was predominant.
A New Bis-fused π-Electron Donor Composed of Tetrathiafulvalene and 2-(Xanthen-9-ylidene)-1,3-dithiole
Authors: Kato Minami , Shirahata Takashi , Misaki Yohji
Published: September 2013

Derivatives of a new bis-fused TTF analogue 2 composed of TTF and 2-(xanthen-9-ylidene)-1,3-dithiole have been synthesized. Cyclic voltammograms of 2 are composed of three pairs of redox waves, of which the third redox wave corresponds to a two-electron-transfer process. X-ray structure analysis of the ReO4− salt of bis(methylthio)-2 [(2b)ReO4(DCE)0.5] revealed that the 2b molecules form a dimerized one-dimensional stack.
Governance Institutions and Adaptation Costs: Evidence from the Fall of the Berlin Wall
Authors: Frank Douglas H.
Published: September 2013

This paper investigates how institutions governing the employment relationship influence firms' adaptation to environmental changes. After the Berlin Wall fell, migration from East Germany accounted for an abrupt increase in the supply of a key resource—labor—in the West. I study responses to this disruption among firms in the economically important machinery and equipment industry. I find that western firms adapted to migration by increasing employment unless they were affiliated with a works council, an institution that limits the firm's autonomy in managing its workforce. I also find evidence of institution-contingent responses to migration in two areas of firm strategy: vertical boundaries and the focus on exploration versus exploitation. The results suggest that “hybrid” (i.e., less hierarchical) governance institutions increase adaptation costs. The results also indicate that such adaptation costs have implications for multiple aspects of firm decision making that are nominally beyond the scope of those governance institutions.

This paper was accepted by Bruno Cassiman, business strategy.
Optimal Hiring and Retention Policies for Heterogeneous Workers Who Learn
Authors: Arlotto Alessandro , Chick Stephen E. , Gans Noah
Published: September 2013

We study the hiring and retention of heterogeneous workers who learn over time. We show that the problem can be analyzed as an infinite-armed bandit with switching costs, and we apply results from Bergemann and Välimäki [Bergemann D, Välimäki J (2001) Stationary multi-choice bandit problems. J. Econom. Dynam. Control 25(10):1585–1594] to characterize the optimal hiring and retention policy. For problems with Gaussian data, we develop approximations that allow the efficient implementation of the optimal policy and the evaluation of its performance. Our numerical examples demonstrate that the value of active monitoring and screening of employees can be substantial.

This paper was accepted by Yossi Aviv, operations management.
Outsourcing Information Security: Contracting Issues and Security Implications
Authors: Cezar Asunur , Cavusoglu Huseyin , Raghunathan Srinivasan
Published: September 2013

A unique challenge in information security outsourcing is that neither the outsourcing firm nor the managed security service provider (MSSP) perfectly observes the outcome, the occurrence of a security breach, of prevention effort. Detection of security breaches often requires specialized effort. The current practice is to outsource both prevention and detection to the same MSSP. Some security experts have advocated outsourcing prevention and detection to different MSSPs. We show that the former outsourcing contract leads to a significant disincentive to provide detection effort. The latter contract alleviates this problem but introduces misalignment of incentives between the firm and the MSSPs and eliminates the advantages offered by complementarity between prevention and detection functions, which may lead to a worse outcome than the current contract. We propose a new contract that is superior to these two on various dimensions.

This paper was accepted by Lorin Hitt, information systems.
Informed Bond Trading, Corporate Yield Spreads, and Corporate Default Prediction
Authors: Han Song , Zhou Xing
Published: September 2013

Taking advantage of recently augmented corporate bond transaction data, we examine the pricing implications of informed trading in corporate bonds and its ability to predict corporate defaults. We find that microstructure measures of information asymmetry seem to capture adverse selection in corporate bond trading reasonably well. We demonstrate that information asymmetry in bond trading has explanatory power for corporate bond yield spreads, and this result holds after controlling for the transaction costs of liquidity, credit risk, and other traditional bond pricing factors. Furthermore, information asymmetry can help forecast corporate defaults after conditioning on other default prediction variables. Such forecasting ability of informed bond trading is especially useful for private firms because the bond market constitutes the only venue for informed traders to exploit their information advantages.

This paper was accepted by Wei Xiong, finance.
The Impact of the Manufacturer-Hired Sales Agent on a Supply Chain with Information Asymmetry
Authors: Khanjari Neda Ebrahim , Iravani Seyed , Shin Hyoduk
Published: September 2013

This paper studies the impact of a manufacturer-hired sales agent on a supply chain comprising a manufacturer and a retailer. The sales agent is working mainly at the retailer's location to boost demand. We focus on a wholesale price contract, under which the retailer decides how much to order from the manufacturer. The information structure within the supply chain and the efficiency of the sales agent affect the supply chain members' expected profits. We show that, because of the agency issue between the sales agent and the manufacturer, when the retailer's demand forecast accuracy is similar to the manufacturer's and the wholesale price is fixed, the retailer's profit decreases as his demand forecast accuracy improves. We also illustrate that when the retailer's forecast accuracy is much better than the manufacturer's and the wholesale price is endogenous, his expected profit decreases as his forecast accuracy improves. Moreover, we demonstrate that having a more efficient sales agent is beneficial for the retailer when the wholesale price is fixed, whereas this is not always the case when the wholesale price depends on the efficiency of the sales agent.
Contracts for Changing Times: Sourcing with Raw Material Price Volatility and Information Asymmetry
Authors: Zhang Wei , Zhou Deke , Liu Liwen
Published: September 2013

We analyze and compare five contract schemes used in a supply chain: fixed price (FP), cost reimbursement (CR), procurement control (PC), index-linked payment (IL), and relational (RL) contracts. From interviews, we learned that (1) FP and RL are the two most popular schemes; (2) PC is less popular, but it is used more often than CR and IL; and (3) a couple of firms are considering CR and IL and will probably use them in the future. By presenting a two-stage contracting model that incorporates a risk-neutral buyer and a risk-averse supplier under raw material price uncertainty and information asymmetry, we show that overhedging the supplier's risk with an IL contract can be optimal for the buyer in many cases. Using the model to study the effects of price trends, risk attitudes, information asymmetry, and constraints on purchase time, we find that each contract can be optimal in certain situations from certain standpoints. In particular, when a long-term relationship is considered, RL is equivalent to IL as long as the contract is self-enforcing, and RL can replace IL when no index is available. Connecting the analytical results to the interviews, we find that firms' choices and considerations can be well understood.
Building on the past: The pâtes-de-verre sculpture of Max Stewart
Authors: Cummings Keith , Stewart Max
Published: September 2013

Professor Keith Cummings and Dr Max Stewart discuss their collaboration in an A.H.R.C.-funded project into the techniques of a glass casting process known as pâte(s)-de-verre within the works of the French pioneer of the process, Amalric Walter (1870–1959). The results of this project (completed in 2006) provided the starting point for the extension of this process, its description and publication in the form of repeatable recipes and clear scientific principles, the generation of new glass colours and their use within a personal body of glass sculpture. The article describes the journey from the original empirical investigation, through the experimental reproduction of Walter’s process, the codification of that process for publication, the extension of the process through the production of new colours and additions to the casting process itself, and their use as expressive vocabulary.
Crafts and successful ageing: The Découpage Guild Australia
Authors: Joseph Dawn , Southcott Jane
Published: September 2013

Community arts can provide older people with opportunities to enhance their quality of life, provide a sense of fulfillment and create a space for teaching, learning and sharing. Our research question asks how and why do older Australian people who are active in society engage with craft? This article discusses one particular case study from a larger ongoing joint research project, ‘Well-being and ageing: Community, diversity and the arts in Victoria’. The project, which began in 2008, has been undertaken by academic researchers from two metropolitan Australian universities in Melbourne, Victoria (Deakin University and Monash University). This research has entailed a number of case studies of individual visual and performing arts community organizations that cater for older people, active in the community. This phenomenological qualitative case study sought in-depth understandings of the group of découpers (all members of the Découpage Guild Australia). Phenomenological research entails an exploration of participants’ lifeworlds, experiences, understandings and perceptions. The data are reported under three overarching themes: Learning and Teaching; Being Creative; and Well-being. The study demonstrates that craft engagement can provide participants with new learning experiences, teaching opportunities in a collaborative community, an outlet for their creativity, which fosters an enhanced sense of self and well-being.
Pottery function and Nkore social activity
Authors: Kwesiga Philip
Published: September 2013

This article presents research regarding the instruction and production of pottery in Uganda during the twentieth century. It investigates how local low-tech pottery and community attitudes, as well as norms and values in traditional Ugandan pottery, have been displaced by competing modern technologies and selected community actions, which they in turn can be seen to influence. The proposition is that this shift in pottery manufacture reflects patterns of contemporary technological, socio-economic, cultural and power relations in Uganda in general and Nkore in particular. The proposition is further that this shift retains previous technological knowledge dispositions, specific to economic, social and cultural history in Uganda and its position in the global market. In other words, past local technology has left its mark on both past and present activities and attitudes to pottery making.
Digital Kanthas: Print waste as ornament
Authors: Rigley Steve
Published: September 2013

This article reflects on a body of practice-based research that considers the recycling of images found in discarded waste sheets from commercial offset-lithography. Specifically, it considers how images derived from Indian print waste might be recycled to create new forms of ornament that reflect upon cross-cultural exchange and globalization. Initially working with large-format waste sheets derived from billboard advertising in the United Kingdom, the author utilized cropping and re-contextualization to create new works. Working with waste gathered from the floors of a thriving print hub in southern India provided an opportunity to extend this exploration to consider waste sheets as catalysts for new forms of ornament, with the content directly referencing themes of historical and contemporary cultural exchange and globalization. Largely facilitated by digital tools and connectivity, a new generation of Indian designers have overseen a significant shift in Indian graphic design over the past twenty years. This has been most evident in the packaging of fireworks and hand-rolled cigarettes, where traditional and religious motifs have increasingly been marginalized in favour of the integration of western, secular imagery. Working with waste sheets used in the packaging of Indian fireworks and cigarettes, the author considers the Bengali Kantha – a traditional form of embroidered blanket – as a suitable model with which to explore new forms of ornament, connecting the traditional crafts practices of India with contemporary graphic design, and in turn provide a platform for a body of new works that reflect on perceived narrowing of the gap between graphic and textile design through digital production and print technologies.
Exhibition Review
Authors: Mallol Mònica Gaspar
Published: September 2013

‘Keypiece: Research at the Threshold’, Research Exhibition and Seminar, Sheffield Hallam University, UK, 19–20 November 2010
Publication Review
Authors: Kane Faith
Published: September 2013

Digital Visions in Fashion + Textiles: Made in Code, Sarah E. Braddock Clarke and Jane Harris (2012) London, UK: Thames & Hudson, 240 pp., ISBN 9780500516447, h/bk, £29.95
Decreased expression of cystic fibrosis transmembrane conductance regulator impairs sperm quality in aged men
Authors: Diao Ruiying , Fok Kin Lam , Zhao Li , Chen Hao , Tang Hui , Chen Jing , Zheng Aiping , Zhang Xiaohu , Gui Yaoting , Chan Hsiao Chang , Cai Zhiming
Published: September 2013

Sperm quality declines with aging; however, the underlying molecular mechanism remains elusive. The cystic fibrosis transmembrane conductance regulator (CFTR) has been shown to play an essential role in fertilizing capacity of sperm and male fertility. This study aimed to investigate the involvement of age-dependent CFTR downregulation in lowering sperm quality in old age. Two hundred and one healthy fertile men of three age groups (20–40 years,n=64; 40–60 years,n=61; and >60 years,n=76) were recruited. Expression of CFTR was determined by RT-PCR, western blot, and immunofluorescence staining. Collected sperm were treated with CFTR inhibitor or potentiator. Sperm quality was assessed by motility and bicarbonate-induced capacitation. The results showed that the expression of CFTR on the equatorial segment and neck region of sperm was significantly decreased in an age-dependent manner. Reduction of CFTR expression in sperm from old men was correlated with lowered forward motility and decreased HCO3−sensitivity required for sperm capacitation. Activation of CFTR by genistein partially rescued the decreased forward motility in sperm from old men. Decreased CFTR expression in sperm was also found to be associated with lowered sperm quality in aging mice. These results suggest that age-dependent downregulation of CFTR in sperm leads to lowered sperm quality in old age sperm. CFTR may be a pontential target for rescuing sperm motility as well as a fertility indicator in old age men.
Ovarian signalling pathways regulated by leptin during the ovulatory process
Authors: Di Yorio María Paula , Bilbao María Guillermina , Biagini-Majorel Ana María , Faletti Alicia Graciela
Published: September 2013

Leptin, a protein secreted by different tissues, is able to exert both stimulatory and inhibitory effects on the ovulatory process. Thus, we investigated whether these opposite effects involve changes in the ovarian signalling pathways in response to different levels of leptin. To this end, we performed both in vivo and in vitro assays using immature rats primed with gonadotrophins to induce ovulation. The acute treatment with leptin, which inhibits the ovulatory process, caused a significant decrease in the phosphorylation of both STAT3 and ERK1/2 and a simultaneous increase in suppressors of cytokine signalling 3 (SOCS3) protein. However, daily administration of a low dose of leptin, which induces the ovulatory process, showed increased phosphorylation of both STAT3 and ERK1/2 and a decreased expression of SOCS3 protein. Using ovarian explant cultures, we also found that leptin was able to activate both STAT3 and ERK1/2 at 10 ng/ml but only STAT3 at 300–500 ng/ml. In addition, at 100–300 ng/ml, leptin increased protein but not mRNA expression of SOCS3. The addition of specific inhibitors of JAK/STAT and MAPK signalling pathways suppressed both the increase and the decrease in leptin-induced progesterone secretion. These results indicate that i) different levels of leptin are able to regulate STAT3, ERK1/2 and SOCS3 at both intra- and extra-ovarian level and that ii) the dual action of leptin on steroidogenesis seems to occur, at least in part, through both the ERK and STAT cascades.
Evidence for Tissue-Specific JAK/STAT Target Genes inDrosophilaOptic Lobe Development
Authors: Wang Hongbin , Chen Xi , He Teng , Zhou Yanna , Luo Hong
Published: September 2013

The evolutionarily conserved JAK/STAT pathway plays important roles in development and disease processes in humans. Although the signaling process has been well established, we know relatively little about what the relevant target genes are that mediate JAK/STAT activation during development. Here, we have used genome-wide microarrays to identify JAK/STAT targets in the optic lobes of the Drosophila brain and identified 47 genes that are positively regulated by JAK/STAT. About two-thirds of the genes encode proteins that have orthologs in humans. The STAT targets in the optic lobe appear to be different from the targets identified in other tissues, suggesting that JAK/STAT signaling may regulate different target genes in a tissue-specific manner. Functional analysis of Nop56, a cell-autonomous STAT target, revealed an essential role for this gene in the growth and proliferation of neuroepithelial stem cells in the optic lobe and an inhibitory role in lamina neurogenesis.
Gene Amplification and Functional Diversification of Melanocortin 4 Receptor at an Extremely Polymorphic Locus Controlling Sexual Maturation in the Platyfish
Authors: Volff Jean-Nicolas , Selz Yvonne , Hoffmann Carsten , Froschauer Alexander , Schultheis Christina , Schmidt Cornelia , Zhou Qingchun , Bernhardt Wolfgang , Hanel Reinhold , Böhne Astrid , Brunet Frédéric , Ségurens Béatrice , Couloux Arnaud , Bernard-Samain Sylvie , Barbe Valérie , Ozouf-Costaz Catherine , Galiana Delphine , Lohse Martin J , Schartl Manfred
Published: September 2013

In two swordtail species of the genus Xiphophorus, the onset of puberty has been shown to be modulated at the P locus by sequence polymorphism and gene copy-number variation affecting the type 4 melanocortin hormone receptor Mc4r. The system works through the interaction of two allelic types, one encoding wild type and the other dominant-negative receptors. We have analyzed the structure and evolution of the P locus in the platyfish Xiphophorus maculatus, where as many as nine alleles of P determining the onset of sexual maturity in males and females, fecundity in females, and adult size in males are located on both the X and Y chromosomes in a region linked to the master sex-determining locus. In this species, mc4r has been amplified to up to 10 copies on both the X and Y chromosomes through recent large serial duplications. Subsequently, mc4r paralogues have diverged considerably into many different subtypes. Certain copies have acquired new untranslated regions through genomic rearrangements, and transposable element insertions and other mutations have accumulated in promoter regions, possibly explaining observed deviations from the classical mc4r transcriptional pattern. In the mc4r-coding sequence, in-frame insertions and deletions as well as nonsense and missense mutations have generated a high diversity of Mc4r-predicted proteins. Most of these variants are expressed in embryos, adults, and/or tumors. Functional receptor characterization demonstrated major divergence in pharmacological behavior for Mc4r receptors encoded by different copies of platyfish mc4r, with differences in constitutive activity as well as binding and stimulation by hormones. The high degree of allelic and copy-number variation observed between individuals can explain the high level of polymorphism for sexual maturation, fecundity, and body size in the platyfish: multiple combinations of Mc4r variants with different biochemical properties might interact to modulate the melanocortin signaling that regulates the hypothalamus–pituitary–gonadal axis.
Initiation of Meiotic Recombination in Ustilago maydis
Authors: Kojic Milorad , Sutherland Jeanette H , Pérez-Martín José , Holloman William K
Published: September 2013

A central feature of meiosis is the pairing and recombination of homologous chromosomes. Ustilago maydis, a biotrophic fungus that parasitizes maize, has long been utilized as an experimental system for studying recombination, but it has not been clear when in the life cycle meiotic recombination initiates. U. maydis forms dormant diploid teliospores as the end product of the infection process. Upon germination, teliospores complete meiosis to produce four haploid basidiospores. Here we asked whether the meiotic process begins when teliospores germinate or at an earlier stage in development. When teliospores homozygous for a cdc45 mutation temperature sensitive for DNA synthesis were germinated at the restrictive temperature, four nuclei became visible. This implies that teliospores have already undergone premeiotic DNA synthesis and suggests that meiotic recombination initiates at a stage of infection before teliospores mature. Determination of homologous recombination in plant tissue infected with U. maydis strains heteroallelic for the nar1 gene revealed that Nar+ recombinants were produced at a stage before teliospore maturation. Teliospores obtained from a spo11Δ cross were still able to germinate but the process was highly disturbed and the meiotic products were imbalanced in chromosomal complement. These results show that in U. maydis, homologous recombination initiates during the infection process and that meiosis can proceed even in the absence of Spo11, but with loss of genomic integrity.
Mapping Quantitative Trait Loci by Controlling Polygenic Background Effects
Authors: Xu Shizhong
Published: September 2013

A new mixed-model method was developed for mapping quantitative trait loci (QTL) by incorporating multiple polygenic covariance structures. First, we used genome-wide markers to calculate six different kinship matrices. We then partitioned the total genetic variance into six variance components, one corresponding to each kinship matrix, including the additive, dominance, additive × additive, dominance × dominance, additive × dominance, and dominance × additive variances. The six different kinship matrices along with the six estimated polygenic variances were used to control the genetic background of a QTL mapping model. Simulation studies showed that incorporating epistatic polygenic covariance structure can improve QTL mapping resolution. The method was applied to yield component traits of rice. We analyzed four traits (yield, tiller number, grain number, and grain weight) using 278 immortal F2 crosses (crosses between recombinant inbred lines) and 1619 markers. We found that the relative importance of each type of genetic variance varies across different traits. The total genetic variance of yield is contributed by additive × additive (18%), dominance × dominance (14%), additive × dominance (48%), and dominance × additive (15%) variances. Tiller number is contributed by additive (17%), additive × additive (22%), and dominance × additive (43%) variances. Grain number is mainly contributed by additive (42%), additive × additive (19%), and additive × dominance (31%) variances. Grain weight is almost exclusively contributed by the additive (73%) variance plus a small contribution from the additive × additive (10%) variance. Using the estimated genetic variance components to capture the polygenic covariance structure, we detected 39 effects for yield, 39 effects for tiller number, 24 for grain number, and 15 for grain weight. The new method can be directly applied to polygenic-effect-adjusted genome-wide association studies (GWAS) in human and other species.
Horizontal pressures in cylindrical metal silos and comparison with different international standards
Authors: Nascimento José W. B. do , Lopes Neto José P. , Montross Michael D.
Published: September 2013

The focus of this research was to evaluate the horizontal pressures on a cylindrical metal silo of corrugated walls and flat bottom with 1.82m diameter and 5.4m high, and to compare the values with those obtained theoretically by the ISO 11697, EP 433 and AS 3774 standards. The silo was symmetrically filled and constant speed with wheat cv. soft red for two different height/diameter ratios (H/D) and was unloaded through three orifices with a diameter of 71.6mm, one concentric and two eccentrics. Horizontal pressures were measured on the walls of the silo at three positions using hydraulic type pressure cells. The results showed that shortly after the start of the unloading, there was a mass flow above the quota of H/D = 1.2, whereas below this quota funnel flow occurred. It can be said that the EP 433 standard was more appropriate to predict horizontal pressures in silos in H/D ratio = 1.0, with eccentric unloading. For the H/D ratio = 1.5, AS 3774 standard was the one that produced values closer to the experimental.
Anaerobic reactors with biofilter and different diameter-length ratios in cassava starch industry wastewater treatment
Authors: Kunzler Kathia R. , Gomes Simone D. , Piana Pitágoras A. , Torres Douglas G. B. , Vilas Boas Marcio A. , Tavares Maria H. F.
Published: September 2013

The use of anaerobic reactors with media support in the treatment of wastewater from the cassava starch industry has emerged as a viable option because it allows the application of high organic loads and a significant reduction of the HDT needed for the treatment. This research aimed at studying the process of biodigestion in two anaerobic reactors with bamboo support, in the treatment of effluent of cassava starch, by evaluating their performance. The two reactors used present the following diameter: length ratio, 1:6 and 1:3. The organic loads applied to the systems were 0.519, 1.156, 1.471, 3.049, 4.347, 4.708 and 5.601g.L-1.d-1. Regarding the efficiency of removal of COD, TS and TVS, no statistically significant differences were obtained between the reactors. The two systems evaluated showed a stable behavior with respect to the VA/TA (volatile acidity/total alkalinity) for all submitted loads. The reactors tended to the maintenance of biogas production as a function of consumed COD for the last three organic loads applied, indicating an ability to withstand higher organic loads.
Energetic analysis of landrace varieties and hybrids of corn produced in different technological levels of management
Authors: Araujo Alisson V. de , Brandão Junior Delacyr da S. , Colen Fernando
Published: September 2013

The aim of this study was to analyze, under the energetic point of view, the cultivation of corn in three management systems (low, medium and high-tech), using two landrace varieties ('Argentino' and 'BR da Várzea'), a double hybrid cultivar (SHS 4080) and a simple hybrid (IAC 8333). Five performance indicators were used: energy efficiency, liquid cultural energy, cultural efficiency, energy balance and productive energy efficiency. From the perspective of family farming, it was verified the largest social importance of the systems under low and medium levels of technology, due to the increase employment capacity of rural labor. The liquid cultural energy and energy balance were more favorable for the system under high technological level, unlike cultural efficiency and productive energy efficiency, which were significantly higher for medium and low technological levels. The variety 'Argentino' showed lower productive energy efficiency. The variety 'BR da Várzea', on the other hand, presented the potential to generate energy as much as the hybrids. In general, the biggest sustainability in the corn crop was achieved when the management system under medium and lower levels of technology were used.
Effects of vinasse application under the physical attributes of soil covered with sugarcane straw
Authors: Costa Cicero da S. , Pedrosa Elvira M. R. , Rolim Mario M. , Santos Hugo R. B. , Cordeiro Neto Aluízio T.
Published: September 2013

Areas under vinasse application have been associated to favorable physical conditions for root development, aeration, infiltration and water movement in soil profile. This study aimed to evaluate changes on physical attributes of soil under sugarcane straw after vinasse application in two sugarcane growing areas (Area 1 and Area 2) under mechanized management in the state of Paraíba, Brazil. In each area, the samples were collected in the 0-0.20, 0.20-0.40 and 0.40-0.60m layers of the soil, in 36 points, distributed in a 10×10m mesh, one day before and 40 days after vinasse application. The data were submitted to multivariate analysis with repeated measures and geostatistics. The vinasse application decreased soil density and increased total porosity in both Areas and increased organic matter in Area 2. In Area 1 occurred pure nugget effect for the fractions of sand, silt and clay, independent of soil layer. In Area 2, this effect was verified mostly at superficial layers, except for the fraction of clay that presented a moderate degree of spatial dependence.
Technical and economic analysis of irrigation of asparagus bean in protected environment
Authors: Silva Wellington G. , Carvalho Jacinto A. , Oliveira Eduardo C. , Lima Júnior Joaquim A. , Silva Buno M.
Published: September 2013

This experiment was conducted in Lavras - state of Minas Gerais (MG), Brazil, in a protected environment, and aims to estimate the irrigation depths that maximize productivity and economic returns in the cultivation of asparagus bean and analyze the economic viability of irrigation management. The experimental delineation was randomized blocks with five treatments and four replications. The treatments consisted of five drip irrigation depths: 40, 70, 100, 130 and 160% of water replacement depth up to field capacity. The depths of water that maximize productivity and economic returns were obtained from the regression model adjusted to productivity data, cost of product relations and water cost. The economic viability was achieved on the benefit/cost ratio basis. The depth with the maximum economic return was estimated in 434.4mm, with a productivity of 35,160.6kg ha-1, which is economically viable for the cultivation of asparagus bean, with a expected profitability of R$ 1.70 for every real invested.
Influence of vinasse application in hydraulic conductivity of three soils
Authors: Uyeda Claudio A. , Miranda Jarbas H. de , Duarte Sergio N. , Medeiros Pedro R. F. de , Dias Carlos T. dos S.
Published: September 2013

The potassium ion, present in great amount in the vinasse because it is a monovalent cation, has the characteristic of promoting the dispersion of clay particles, in the same way as the sodium, causing a reduction in the pore space of the soil and, in its turn, reducing its permeability. To evaluate this effect of reduction by application of vinasse to the soil, an experiment was conducted for three different soils, with the objective of evaluating the effect of the application of different doses of vinasse on hydraulic conductivity of saturated soil and verifying its possible chemical changes of these soils. For that, it was used PVC columns (in a scheme of constant head permeameter to obtain the values of hydraulic conductivity of saturated soil), filled with three soils - Dark Red Latosol (DRL), Purple Latosol (PL) and Eutrophic Red Nitossol (ERN) - , in which were applied four doses of vinasse (0, 150, 300 and 450m³ ha-1), distributed in a completely randomized design with a 3x4 factorial scheme with three replications. The results evidenced that only the Dark Red Latosol (DRL) showed a reduction in the values of hydraulic conductivity of saturated soil, and in front of the application of vinasse, up to 300m³ ha-1, it was observed an increase in the concentrations of potassium, calcium and cation exchange capacity (CEC) ions.
Fragment size of corn silage according to the dry matter and forage harvester adjustments
Authors: Weirich Neto Pedro H. , Garbuio Paulo W. , Souza Nátali M. de , Delalibera Hevandro C. , Leitão Khetlen
Published: September 2013

In Brazil, the best results in milk production are found in the state of Paraná. Such results are reached through genetic selection of the animals and management of their diets, in which whole plant corn silage is widely used. Aiming the silage quality, it was evaluated the influence of dry matter content of the corn culture as forage and the harvester adjustments on the fragment size of whole plant corn silage. The fragment size of two corn hybrids silage (SPEED and 2B688) was evaluated using a 5x3 factorial, with 4 repetitions. The first factor was the harvest time of the plants (105, 108, 112, 118, and 123 days after sowing (DAS)), which determines the forage dry matter (DM) content. The second factor was the harvester adjustments (2, 6.5 and 11mm of theoretical fragment length (TFL)). The DM content did not affect the average fragment size of 2B688. For SPEED, however, the real fragment size decreased as the maturation of plants increased. The conclusion is that the DM content and harvester adjustments can affect the real fragment sizes, according to different plant genotypes. The alterations of the harvester adjustments resulted in different fragment sizes, however, it were different from those indicated by the manufacturer.
Analysis and forecast of the storage needs of soybeans in Brazil
Authors: Patino Marco T. O. , Machado Marina F. , Nascimento Geraldo T. do , Alcantara Milla R. de
Published: September 2013

The existence of a minimum storage capacity of grains as a condition for the maintenance of regulator physical stocks has been used as a strategic factor in the agribusiness expansion. However, in Brazil the storage infrastructure has not followed the growth of the agricultural sector. This fact is evident in the case of soybeans that currently represent 49% of grain production in the country, whose volume production has been increasing significantly over the years. This study aimed to predict the futureï€ needs of static storage capacity of soybeans from historical data to estimate the investment needed to install storage units in Brazil for the next five years. A statistic analysis of collected data allowed a forecast and identification of the number of storage units that should be installed to meet the storage needs of soybeans in the next five years. It was concluded that by 2015 the soybean storage capacity should be 87 million tons, and to store 49% of soybeans produced, 1,104 storage units should be installed at a cost of R$ 442 million.