Nutrient Transport in the Mammary Gland: Calcium, Trace Minerals and Water Soluble Vitamins.

Milk nutrients are secreted by epithelial cells in the alveoli of the mammary gland by several complex and highly coordinated systems. Many of these nutrients are transported from the blood to the milk via transcellular pathways that involve the concerted activity of transport proteins on the apical and basolateral membranes of mammary epithelial cells. In this review, we focus on transport mechanisms that contribute to the secretion of calcium, trace minerals and water soluble vitamins into milk with particular focus on the role of transporters of the SLC series as well as calcium transport proteins (ion channels and pumps). Numerous members of the SLC family are involved in the regulation of essential nutrients in the milk, such as the divalent metal transporter-1 (SLC11A2), ferroportin-1 (SLC40A1) and the copper transporter CTR1 (SLC31A1). A deeper understanding of the physiology and pathophysiology of these transporters will be of great value for drug discovery and treatment of breast diseases.

Apatani phonology and lexicon, with a special focus on tone

Despite being one of the most extensively researched of Eastern Himalayan languages, the basic morphological and phonological-prosodic properties of Apatani (Tibeto-Burman > Tani > Western) have not yet been adequately described. This article attempts such a description, focusing especially on interactions between segmental-syllabic phonology and tone in Apatani. We highlight three features in particular – vowel length, nasality and a glottal stop – which contribute to contrastively-weighted syllables in Apatani, which are consistently under-represented in previous descriptions of Apatani, and in absence of which tone in Apatani cannot be effectively analysed. We conclude that Apatani has two “underlying”, lexically-specified tone categories H and L, whose interaction with word structure and syllable weight produce a maximum of three “surface” pitch contours – level, falling and rising – on disyllabic phonological words. Two appendices provide a set of diagnostic procedures for the discovery and description of Apatani tone categories, as well as an Apatani lexicon of approximately one thousand entries.

Altered transmission of HOX and apoptotic SNPs identify a potential common pathway for clubfoot.

Clubfoot is a common birth defect that affects 135,000 newborns each year worldwide. It is characterized by equinus deformity of one or both feet and hypoplastic calf muscles. Despite numerous study approaches, the cause(s) remains poorly understood although a multifactorial etiology is generally accepted. We considered the HOXA and HOXD gene clusters and insulin-like growth factor binding protein 3 (IGFBP3) as candidate genes because of their important roles in limb and muscle morphogenesis. Twenty SNPs from the HOXA and HOXD gene clusters and 12 SNPs in IGFBP3 were genotyped in a sample composed of non-Hispanic white and Hispanic multiplex and simplex families (discovery samples) and a second sample of non-Hispanic white simplex trios (validation sample). Four SNPs (rs6668, rs2428431, rs3801776, and rs3779456) in the HOXA cluster demonstrated altered transmission in the discovery sample, but only rs3801776, located in the HOXA basal promoter region, showed altered transmission in both the discovery and validation samples (P = 0.004 and 0.028). Interestingly, HOXA9 is expressed in muscle during development. An SNP in IGFBP3, rs13223993, also showed altered transmission (P = 0.003) in the discovery sample. Gene-gene interactions were identified between variants in HOXA, HOXD, and IGFBP3 and with previously associated SNPs in mitochondrial-mediated apoptotic genes. The most significant interactions were found between CASP3 SNPS and variants in HOXA, HOXD, and IGFBP3. These results suggest a biologic model for clubfoot in which perturbation of HOX and apoptotic genes together affect muscle and limb development, which may cause the downstream failure of limb rotation into a plantar grade position.

PREPARATION AND CHARACTERIZATION OF COVALENTLY LINKED ENZYME-ANTIBODY CONJUGATES AND THEIR USE IN MEASURING MINUTE QUANTITIES OF PROTEIN ANTIGENS

The discovery and characterization of oncofetal proteins have led to significant advances in early cancer diagnosis and therapeutic monitoring of patients undergoing cancer chemotherapy. These tumor-associated antigens are presently measured by sensitive, specific immunoassay techniques based on the detection of minute amounts of labeled antigen or antibody incorporated into immune complexes, which must be isolated from free antigen and antibody.^ Since there are several disadvantages with using radioisotopes, the most common immunolabel, one major objective was to prepare covalently coupled enzyme-antibody conjugates and evaluate their use as a practical alternative to radiolabeled immune reagents. An improved technique for the production of enzyme-antibody conjugates was developed that involves oxidizing the carbohydrate moieties on a glycoprotein enzyme, then introducing antibody in the presence of polyethylene glycol (PEG). Covalent enzyme-antibody conjugates involving alkaline phosphatase and amyloglucosidase were produced and characterized.^ In order to increase the sensitivity of detecting the amyloglucosidase-antibody conjugate, an enzyme cycling assay was developed that measures glucose, the product of maltose cleavage by amyloglucosidase, in the picomole range. The increased sensitivity obtained by combined usage of the amyloglucosidase-antibody conjugate and enzyme cycling assay was then compared to that of conventional enzyme immunoassay (EIA).^ For immune complex isolation, polystyrene tubes and protein A-bearing Staphylococcus aureus were evaluated as solid phase matrices, upon which antibodies can be immobilized. A sandwich-type EIA, using antibody-coated S. aureus, was developed that measures human albumin (HSA) in the nanogram range. The assay, using an alkaline phosphatase-anti-HSA conjugate, was applied to the determination of HSA in human urine and evaluated extensively for its clinical applicability.^ Finally, in view of the clinical significance of alpha-fetoprotein (AFP) as an oncofetal antigen and the difficulty with its purification for use as an immunogen and assay standard, a chemical purification protocol was developed that resulted in a high yield of immunochemically pure AFP. ^

Information-Centric Networking in Mobile and Opportunistic Networks

Information Centric Networking (ICN) as an emerging paradigm for the Future Internet has initially been rather focusing on bandwidth savings in wired networks, but there might also be some significant potential to support communication in mobile wireless networks as well as opportunistic network scenarios, where end systems have spontaneous but time-limited contact to exchange data. This chapter addresses the reasoning why ICN has an important role in mobile and opportunistic networks by identifying several challenges in mobile and opportunistic Information-Centric Networks and discussing appropriate solutions for them. In particular, it discusses the issues of receiver and source mobility. Source mobility needs special attention. Solutions based on routing protocol extensions, indirection, and separation of name resolution and data transfer are discussed. Moreover, the chapter presents solutions for problems in opportunistic Information-Centric Networks. Among those are mechanisms for efficient content discovery in neighbour nodes, resume mechanisms to recover from intermittent connectivity disruptions, a novel agent delegation mechanisms to offload content discovery and delivery to mobile agent nodes, and the exploitation of overhearing to populate routing tables of mobile nodes. Some preliminary performance evaluation results of these developed mechanisms are provided.

Swiss Adolescents' Career Aspirations: Influence of Context, Age, and Career Adaptability

This study investigated the content, realism, stability, and coherence of the career aspirations of 262 students in seventh grade in Switzerland (ages 13-15 years). The content analysis revealed that 82% of the participants named at least one realistic career aspiration, and aspirations showed clear resemblance to existing opportunities in the environment. Quantitative analyses confirmed the hypotheses that realism and stability of aspirations over a 10-month period could better be predicted by individual degree of career adaptability as measured by planfulness and exploration than by chronological age when grade level was controlled for. Coherence of aspirations was not related to age or adaptability. Students attending basic scholastic requirements school tracks reported more adaptability but not more realistic, stable, or coherent aspirations compared to students in advanced requirements tracks.

Completion and Publication Rates of Randomized Controlled Trials in Surgery: An Empirical Study.

OBJECTIVE: To investigate the prevalence of discontinuation and nonpublication of surgical versus medical randomized controlled trials (RCTs) and to explore risk factors for discontinuation and nonpublication of surgical RCTs. BACKGROUND: Trial discontinuation has significant scientific, ethical, and economic implications. To date, the prevalence of discontinuation of surgical RCTs is unknown. METHODS: All RCT protocols approved between 2000 and 2003 by 6 ethics committees in Canada, Germany, and Switzerland were screened. Baseline characteristics were collected and, if published, full reports retrieved. Risk factors for early discontinuation for slow recruitment and nonpublication were explored using multivariable logistic regression analyses. RESULTS: In total, 863 RCT protocols involving adult patients were identified, 127 in surgery (15%) and 736 in medicine (85%). Surgical trials were discontinued for any reason more often than medical trials [43% vs 27%, risk difference 16% (95% confidence interval [CI]: 5%-26%); P = 0.001] and more often discontinued for slow recruitment [18% vs 11%, risk difference 8% (95% CI: 0.1%-16%); P = 0.020]. The percentage of trials not published as full journal article was similar in surgical and medical trials (44% vs 40%, risk difference 4% (95% CI: -5% to 14%); P = 0.373). Discontinuation of surgical trials was a strong risk factor for nonpublication (odds ratio = 4.18, 95% CI: 1.45-12.06; P = 0.008). CONCLUSIONS: Discontinuation and nonpublication rates were substantial in surgical RCTs and trial discontinuation was strongly associated with nonpublication. These findings need to be taken into account when interpreting surgical literature. Surgical trialists should consider feasibility studies before embarking on full-scale trials.

Achievements and Prospects of Tef Improvement - Proceedings of the Second International Workshop, November 7-9, 2011, Debre Zeit, Ethiopia

These proceedings on ‘Achievements and Prospects of tef Improvement’ is the outcome of the Second International Tef Workshop held at Debre Zeit (Ethiopia), the location which represents the major tef growing areas in the country as well as the oldest and biggest center on tef research. As an indigenous crop, the bulk of tef research is carried out in the country by scientists based at various higher-learning and research institutions. Hence, unlike major crops of the world such as wheat and rice, research on tef benefited little from modern improvement techniques. However, in the recent years, there is an increasing interest by several researchers and funding organizations in developed nations to promote tef research and development through implementation of modern genetic and genomic tools. The recent efforts and progresses made on tef research and development were presented and discussed in detail at the workshop. The tef research and development in Ethiopia has recently shown tremendous improvement. This is witnessed by the decision of the Ethiopian government to award a Gold Medal in November 2012 to our Institute for the discovery and promotion of a very popular Quncho variety. At this juncture, I would like to congratulate all involved in research and development of tef as the achievement was obtained due to concerted efforts of the tef community. The editors of the proceedings did a wonderful job of undertaking the painstaking task of editing all 23 manuscripts presented at the workshop. In addition, the proceedings include a 44-point roadmap for future tef research and development which can be used as a guideline for researchers, development workers and policy makers. I would like to extend my thanks to sponsors of the workshop and the publication of the proceedings.

Cross-Country Evidence on Output Growth Volatility: Nonstationary Variance and GARCH Models

This paper revisits the issue of conditional volatility in real GDP growth rates for Canada, Japan, the United Kingdom, and the United States. Previous studies find high persistence in the volatility. This paper shows that this finding largely reflects a nonstationary variance. Output growth in the four countries became noticeably less volatile over the past few decades. In this paper, we employ the modified ICSS algorithm to detect structural change in the unconditional variance of output growth. One structural break exists in each of the four countries. We then use generalized autoregressive conditional heteroskedasticity (GARCH) specifications modeling output growth and its volatility with and without the break in volatility. The evidence shows that the time-varying variance falls sharply in Canada, Japan, and the U.K. and disappears in the U.S., excess kurtosis vanishes in Canada, Japan, and the U.S. and drops substantially in the U.K., once we incorporate the break in the variance equation of output for the four countries. That is, the integrated GARCH (IGARCH) effect proves spurious and the GARCH model demonstrates misspecification, if researchers neglect a nonstationary unconditional variance.

Dynamic Stock Market Interactions between the Canadian, Mexican, and the United States Markets: The NAFTA Experience

This paper explores the dynamic linkages that portray different facets of the joint probability distribution of stock market returns in NAFTA (i.e., Canada, Mexico, and the US). Our examination of interactions of the NAFTA stock markets considers three issues. First, we examine the long-run relationship between the three markets, using cointegration techniques. Second, we evaluate the dynamic relationships between the three markets, using impulse-response analysis. Finally, we explore the volatility transmission process between the three markets, using a variety of multivariate GARCH models. Our results also exhibit significant volatility transmission between the second moments of the NAFTA stock markets, albeit not homogenous. The magnitude and trend of the conditional correlations indicate that in the last few years, the Mexican stock market exhibited a tendency toward increased integration with the US market. Finally, we do note that evidence exists that the Peso and Asian financial crises as well as the stock-market crash in the US affect the return and volatility time-series relationships.

Scientific Production on Open Access : A Worldwide Bibliometric Analysis in the Academic and Scientific Context

This research aims to diachronically analyze the worldwide scientific production on open access, in the academic and scientific context, in order to contribute to knowledge and visualization of its main actors. As a method, bibliographical, descriptive and analytical research was used, with the contribution of bibliometric studies, especially the production indicators, scientific collaboration and indicators of thematic co-occurrence. The Scopus database was used as a source to retrieve the articles on the subject, with a resulting corpus of 1179 articles. Using Bibexcel software, frequency tables were constructed for the variables, and Pajek software was used to visualize the collaboration network and VoSViewer for the construction of the keywords' network. As for the results, the most productive researchers come from countries such as the United States, Canada, France and Spain. Journals with higher impact in the academic community have disseminated the new constructed knowledge. A collaborative network with a few subnets where co-authors are from different countries has been observed. As conclusions, this study allows identifying the themes of debates that mark the development of open access at the international level, and it is possible to state that open access is one of the new emerging and frontier fields of library and information science

Scientific Production on Open Access : A Worldwide Bibliometric Analysis in the Academic and Scientific Context

This research aims to diachronically analyze the worldwide scientific production on open access, in the academic and scientific context, in order to contribute to knowledge and visualization of its main actors. As a method, bibliographical, descriptive and analytical research was used, with the contribution of bibliometric studies, especially the production indicators, scientific collaboration and indicators of thematic co-occurrence. The Scopus database was used as a source to retrieve the articles on the subject, with a resulting corpus of 1179 articles. Using Bibexcel software, frequency tables were constructed for the variables, and Pajek software was used to visualize the collaboration network and VoSViewer for the construction of the keywords' network. As for the results, the most productive researchers come from countries such as the United States, Canada, France and Spain. Journals with higher impact in the academic community have disseminated the new constructed knowledge. A collaborative network with a few subnets where co-authors are from different countries has been observed. As conclusions, this study allows identifying the themes of debates that mark the development of open access at the international level, and it is possible to state that open access is one of the new emerging and frontier fields of library and information science

Scientific Production on Open Access : A Worldwide Bibliometric Analysis in the Academic and Scientific Context

This research aims to diachronically analyze the worldwide scientific production on open access, in the academic and scientific context, in order to contribute to knowledge and visualization of its main actors. As a method, bibliographical, descriptive and analytical research was used, with the contribution of bibliometric studies, especially the production indicators, scientific collaboration and indicators of thematic co-occurrence. The Scopus database was used as a source to retrieve the articles on the subject, with a resulting corpus of 1179 articles. Using Bibexcel software, frequency tables were constructed for the variables, and Pajek software was used to visualize the collaboration network and VoSViewer for the construction of the keywords' network. As for the results, the most productive researchers come from countries such as the United States, Canada, France and Spain. Journals with higher impact in the academic community have disseminated the new constructed knowledge. A collaborative network with a few subnets where co-authors are from different countries has been observed. As conclusions, this study allows identifying the themes of debates that mark the development of open access at the international level, and it is possible to state that open access is one of the new emerging and frontier fields of library and information science

Characteristics and radiocarbon ages of four retrogressive thaw slumps on Herschel Island and King Point

Four retrogressive thaw slumps (RTS) located on Herschel Island and the Yukon coast (King Point) in the western Canadian Arctic were investigated to compare the environmental, sedimentological and geochemical setting and characteristics of zones in active and stabilised slumps and at undisturbed sites. In general, the slope, sedimentology and biogeochemistry of stabilised and undisturbed zones differ, independent of their age or location. Organic carbon contents were lower in slumps than in the surrounding tundra, and the density and compaction of slump sediments were much greater. Radiocarbon dating showed that RTS were likely to have been active around 300 a BP and are undergoing a similar period of increased activity now. This cycle is thought to be controlled more by local geometry, cryostratigraphy and the rate of coastal erosion than by variation in summer temperatures.