bluuebunny/crossref_metadata_2025 huggingface dataset:
Training mid-level health cadres to improve health service delivery in rural Bangladesh
Authors: Rawal Lal B. , Mahmud Kawkab , Islam Sheikh Md. S. , Mahumud Rashidul A. , Nuruzaman Md. , Ahmed Syed M.
Published: March 2016

Introduction

In recent years, the government of Bangladesh has encouraged private sector involvement in producing mid-level health cadres including Medical Assistants (MAs). The number of MAs produced has increased significantly. We assessed students’ characteristics, educational services, competencies and perceived attitudes towards health service delivery in rural areas.

Methods

We used a mixed method approach using quantitative (questionnaire survey) and qualitative (key informant interviews and roundtable discussion) methods. Altogether, five public schools with 238 students and 30 private schools with 732 students were included. Statistical analyses were performed using STATA v-12. Qualitative data were analyzed thematically.

Findings

The majority of the students in both public (66%) and private medical assistant training schools (MATS) (61%) were from rural backgrounds. They spent the majority of their time in classroom learning (public 45% versus private 42%) and the written essay exam was the common form of a students’ performance assessment. Compared with students of public MATS, students of private MATS were more confident in different aspects of educational areas, including managing emerging health needs (P<0.001); evidence-based practice (P=0.002); critical thinking and problem solving (P=0.02), and use of IT/computer skills (P<0.001). Students were aware of not having adequate facilities in rural areas (public 71%, private 65%), but they perceived working in rural areas will offer several benefits, including use of learnt skills; friendly rural people; and opportunities for real-life problem solving, etc.

Conclusion

This study provides a current picture of MATS students’ characteristics, educational services, competencies and perception towards working in rural areas. The MA students in both private and public sectors showed a greater level of willingness to serve in rural health facilities. The results are promising to improve health service delivery, particularly in rural and hard-to-reach areas of Bangladesh.
Production of Helium in Massive Objects
Authors: Wagoner Robert V.
Published: March 2016

The production of helium within supermassive stars, supermassive disks, and ‘little bangs’ is discussed. The conclusions are summarized at the end of the paper.
New Techniques in Space Radio-Astronomy
Authors: Steinberg J.-L.
Published: March 2016

In spite of the title of this paper, it is not easy to point out many significant developments in the techniques of space radio-astronomy in the last few years. Radio-astronomers are limited in their endeavours by several difficulties which they have not yet been able to overcome completely. I still remember F.G. Smith, in his 1965 Liège Symposium talk, saying that “space radioastronomy is in great danger of turning to geophysics”. This statement seems still valid three years later.

However, we might consider that this tendency to deal with geophysical phenomena more than with observations of real astrophysical significance, is after all, not so bad. First of all, it is becoming more and more difficult to define the boundary between geophysics and astrophysics. And second, the Earth environment can be used as a laboratory where a number of processes which are assumed to take place in celestial bodies can be studied in situ. Some types of radio emissions observed by space telescopes are still to be explained and could very well lead to the understanding of mechanisms overlooked by the theoreticians. Radiophysical methods make a very powerful tool to study these phenomena, which occur in a medium that is now being extensively probed by rockets and satellites which send a continuous flow of data to the Earth, about 100000 bits per second, according to Parker.
Bibliography on Galactic Structure in the Direction of Polar Caps
Authors: Gliese W. , Jaschek C. , McCarthy M. F.
Published: March 2016

The notion of preparing a bibliography on the topic of today’s Joint Discussion originated at about the same time in Heidelberg, Strasbourg and Castel Gandolfo. Letters and lists were exchanged as we prepared for our work here today; you must judge the results of this draft and help us with your suggestions. New IAU policy prefers that bibliographical materials be limited to Reports on Astronomy of the various commissions; hence there is no place in Highlights of Astronomy for the full Bibliography. Both the Director of the Vatican Observatory and the Director of the Strasbourg Centre de Données Stellaires have offered to publish the final listing. We are grateful to both and shall accept the Strasbourg offer; it is planned that it will appear in the January 1977 issue of the Information Bulletin.

After listing the author, year of publication, an abbreviated publication reference together with Volume and page references and the title of the paper, we have listed, wherever possible, three additional sets of numbers. The first gives the approximate number of stars discussed in the paper; the second, the approximate magnitude range; and the third, the lower limit of the (absolute) latitude of stars contained in the paper. It should be noted that it was not always possible to furnish all these data for each article listed. Still to be added to the present compilation are the Reference Numbers to the Astronomy and Astrophysics Numeration in preparation by Gliese, a full list of bibliographical abbreviations used prepared by Jaschek and an Author Index and a preface written by McCarthy.
M Dwarfs and the Missing Mass
Authors: Thé P. S.
Published: March 2016

This is a short report on our study of the M dwarfs in the South Galactic Pole region in connection with the problem of the missing mass and the luminosity function of intrinsically faint stars. The M-type stars found in our objective prism survey with the Lembang Schmidt telescope have been studied in collaboration with Dr. D.H.P. Jones for the discrimination between dwarfs and giants. Furthermore, these stars are all observed photo-electrically in Kron’s R, I-system at La Silla, Chile. Results of the work will be published soon. A blink survey has been initiated at Nymegen using copies of red and blue Mt. Palomar Sky survey plates to find faint red stars in the S.G.P.-region.

Kumar has put forward the idea that Oort’s missing mass is to be found as a large number of very low mass stars (0.01-0.07 Mθ) in the solar neighbourhood. His idea is backed up by the fact that stars within this mass range have been found by double star observers. Staller suggested that the low velocity M dwarfs found in the directions of the galactic poles represent Kumar’s very low mass stars. This proposal is ment not only for giving an answer to the problem of the missing mass but also for those problem connected with the observed small velocity dispersion (10-15 km/sec) of the low velocity M dwarfs. Staller estimated the contracting and cooling times of these stars to be about 5 x 108 to 109 years. In the lifetime of our galaxy (about 10 years) 10 to 20 generations of these low mass stars have been created and evolve to very faint degenerated black dwarfs. The mass density of these stars, in the solar neighbourhood, will be large enough to solve the problem of the missing mass. The stars we observe at present as low velocity M stars are genuinely young red stars, and their small velocity dispersion will therefore not contradict Spitzer and Schwarzschild’s mechanism for the creation of “velocity dispersion by encounters with interstellar clouds. The age of the older very faint black dwarfs is comparable to that of our galaxy. These stars should therefore have a large velocity dispersion. Staller has shown that on the average the low mass stars have a velocity dispersion larger than 21 km/sec, and therefore the whole group of low mass stars is satisfying Toomre’s stability criterion for the galactic disk, such as newly derived by Biermann.
Global Oscillations of the Sun
Authors: Deubner Franz-Ludwig
Published: March 2016

The topic of this Joint Discussion has received enormously increased interest in the last couple of years, owing to its potential for the investigation of the structure of the interior of the sun, including related topics like the structure of the convection zone, solar metal abundance, and the still unsettled neutrino problem.

The first stimuli came from the startling observations of Hill et al. (1976) in Arizona, Severny et al. (1976) on Crimea, and Brookes et al. (1976) in Birmingham, accompanied by a large volume of theoretical papers, the details of analysis of which soon went beyond the actual status of the observational facts.

We then witnessed, however, the success of considerable refinements of the techniques of observation, together with an obvious widespread temptation to push the interpretation of many of the new results to the limits of optimism. Yet, despite of the still increasing body of data suggesting the reality of the solar origin of the observed phenomena, much scepticism was prompted by the complicated statistics and the intricate numerical procedures involved in the data analysis, as well as by the great uncertainty about the significance and the amounts of “noise” contributed to the signal by electronics, changes of the conditions of the ray path within the telescope, terrestrial atmospheric inhomogeneities and solar quasi-stationary motions.
A Summary of the Joint Discussion at Patras on Solar Luminosity Variations
Authors: Eddy J. , Foukal P.
Published: March 2016

The most interesting result in solar luminosity studies in the past decade has been the detection of significant variations in the total irradiance by precision radiometers on the NIMBUS-7 and SMM spacecraft. A substantial fraction of the observed variation can be attributed to sunspot blocking. Thermal storage models indicate that the blocked flux can be stored in a slight increase of the thermal and potential energy of the convective zone. The thermal storage time is likely to far exceed one solar activity cycle, implying an 11-year modulation of the solar constant at a level of about 0.1%. Direct observations of the 11-year or longer variations are more difficult but there is some evidence for secular trends below about 0.4% amplitude over the 14-year period of modern sampling. Ongoing stellar photometric programs suggest that luminosity changes exceeding 1% may have been detected in young, chromospherically active stars.

H. S. Hudson (University of California, San Diego) reviewed observations of short-term solar irradiance variations from spacecraft, commenting principally on the precision measurements of the solar constant (S) made by the Active Cavity Radiometer (ACRIM) on the Solar Maximum Mission (SMM) spacecraft (Willson et al., 1981).
Current Trends in Meteor Spectroscopy
Authors: Millman Peter M.
Published: March 2016

A detailed summary of the progress of meteor spectroscopy over more than a century has been published recently (Millman 1980), and only a few historical facts will be noted here. Serious research in this field was initiated by Alexander Stewart Herschel, a grandson of Sir William Herschel, in 1863 (Herschel 1865). Originally, the observational data were entirely visual records but, in the first decade of the twentieth century, a brief program for the photography of meteor spectra was carried out at the Moscow Observatory by S. Blajko (1907). Interest in this type of observation developed slowly and further programs were not attempted until the thirties. At the outbreak of World War II some 60 meteor spectra had been photographed. In the post-war period a general interest in the upper atmosphere led to the development of more efficient meteor cameras which employed replica gratings, and later electronic image-intensification systems recording on video tape (Hemenway et al. 1971; Clifton et al. 1979). As a result several thousand meteor spectra are now available for study.
Workshop of Women in Astronomy
Authors: Torres-Peimbert Silvia
Published: March 2016

This workshop was organized to analyze the present problems of women as astronomers and to focus on possible ways to improve the situation in view of the various contexts in the different countries.

To set up a framework for this analysis the statistical data from the IAU membership (Bergeron 1992) is presented in Table 1. This table only includes countries with 50 or more members and is ordered by the fraction of women participation; values for the overall membership are included.
Helioseismology, solar evolution and other physics
Authors: Demarque P. , Chaboyer B. , Guenther D.B. , Pinsonneault M.H.
Published: March 2016

The last few years have seen rapid progress in solar interior modeling, and standard solar models (SSM) now predict a p-mode oscillation spectrum which agrees, within the estimated uncertainties in the physical input, with the observed oscillation spectrum of the Sun (Guenther et al., 1992a, 1992b; Guzik & Cox, 1993). This is the result of a number of improvements in the input physics, most notably the advances in opacities for the solar interior (Rogers & Iglesias, 1994) and the low temperature regions of the Sun (Kurucz, 1991). The agreement between the observed solar p-mode frequencies and the frequencies predicted by the SSM is not yet perfect, however, and understanding these discrepancies has become a focus of our research.
The Luminosity Determination
Authors: Gómez A.E. , Turon C.
Published: March 2016

The Hertzprung-Russel (HR) diagram luminosity calibration relies basically on three kinds of data: trigonometric parallaxes, kinematical data (proper motions and radial velocities) and cluster distances obtained by the zero-age main sequence fitting procedure. The most fundamental method to calculate the absolute magnitude is the use of trigonometric parallaxes, but up to now, accurate data only exist for stars contained in a small volume around the sun. Individual absolute magnitudes are obtained using trigonometric parallaxes or photometric and spectroscopic calibrations. In these calibrations the accuracy on the absolute magnitude determination ranges from ±0.m2 in the main sequence to ±0m5 in the giant branch. On the other hand, trigonometric parallaxes, kinematical data or cluster distances have been used to make statistical calibrations of the absolute magnitude. The standard error on the mean absolute magnitude calibrations ranges from ±0m3 to ±0m6 on the mean sequence, from ±0m5 to ±0m7 on thegiant branch and is of about 1mfor supergiants.

Future improvements in the absolute magnitude determination will depend on the improvement of the basic data from the ground and space. A brief overview of the new available data is presented. In particular, the analysis of the first 30 months data of the Hipparcos mission (H30) (from the 37 months data of the whole mission) allows to perform a statistical evaluation of the improvements expected in the luminosity determination.
Lithium Depletion in Late-Type Stars Through Wind-Driven Mixing
Authors: Zahn J.-P.
Published: March 2016

A well established property of late-type stars is that their rotation rate and their lithium abundance both decline with age. We understand why such stars are spun down while losing so little mass (Schatzman 1962), but we are still working on a theory which would explain all aspects of the observed lithium depletion. Although most agree that some kind of mixing must occur below the convective envelope of late-type stars, which transports 7Li to the depth where it is destroyed through nuclear burning, the physical process which is responsible for this transport is still in debate. However the most recent observations of the lithium abundance in close binary stars clearly show that there is a causal link between the destruction of lithium and the loss of angular momentum: consistently, tidally-locked binaries tend to display more lithium than single stars of the same effective temperature, as observed in the Hyades (Soderblom et al. 1990, Thorburn et al. 1993) and among old disk stars and halo stars (Spite et al. 1994).
Nomenclature in Kuiper Belt
Authors: Gladman Brett
Published: March 2016

Given the advances in our understanding of the dynamical structure in the Kuiper Belt since 1990, this paper re-examines nomenclature issues regarding dynamical structures in the belt.
A TNO Survey Project with the 2.2m Telescope at ESO La Silla
Authors: Boehnhardt Hermann , Hainaut Olivier
Published: March 2016

We propose a wide-shallow TNO search to be done with the Wide Field Imager (WFI) instrument at the 2.2m MPG/ESO telescope in La Silla/Chile. The WFI is a half-deg camera equipped with an 8kx8k CCD (0.24 arcsec/pixel). It was used in 1999 to run a pilot project for a TNO search. Using the images of typically 24mag limiting brightness and an automatic detection software (developed at ESO Chile) it was possible to discover 6 TNOs in a small search area of 1.5 sdeg. The project is now continued on a somewhat larger scale in order to discover more TNOs in a systematic way and to reach operational status for a full on-line detection of the objects as well as astrometric and photometric reduction at the telescope. The final goal is to perform a survey of a major part of the sky (typically 2000 sdeg in and out of the ecliptic) down to 24mag. Follow-up astrometry and photometry of the expected more than 3000 discovered objects will secure their orbital and physical characterisation for synoptic dynamical and taxonomic studies of the transneptunian population.
History of Cometary Exploration at Kyiv University
Authors: Churyumov K.I.
Published: March 2016

The comet explorers at Kyiv University took part in numerous international observational programs for study of comets: C/1973 E1 Kohoutek in 1974, 27P/Crommelin in 1984, 1P/ Halley in 1986, 23P/Brorsen-Metcalf in 1989, D/Shoemaker-Levy 9 in 1994, C/1996 B2 Hyakutake in 1996, C/1995 O1 Hale-Bopp in 1997, C/1999 S4 (LINEAR) in 2000 and others. Two comets, 67P/Churyumov-Gerasimenko in 1969 and C/1986 N1 (Churyumov-Solodovnikov) in 1986, were discovered. During 1939-2000 more than 1000 scientific papers devoted to comets were published in different journals, books and proceedings.
The Status of Oxygen Abundances in Metal-Poor Stars
Authors: Peterson Ruth C.
Published: March 2016

The sensitivity of various methods of oxygen-abundance determination to the structure of the model atmosphere in a classical analysis is described, with emphasis on the treatment of convection. Oxygen-abundance results presented during this meeting are outlined. Because the oxygen diagnostics are sensitive in different ways to the choice of model stellar parameters and to the treatment of convection, it is not surprising that different methods applied by different groups give different results. Most are consistent with an increase in [O/Fe] as [Fe/H] declines, but the slope is uncertain still, and the scatter is large at very low abundances. The trend may continue to low [Fe/H], but more stars and more checks are needed.
Beagle 2: The Astrobiology Lander on ESA’s Mars Express Mission
Authors: Sims M.R. , Pillinger C.T. ,   on behalf of the Beagle 2 consortium
Published: March 2016

Due for launch in 2003 as part of the Mars Express mission, the primary goal of the Beagle 2 lander is the detection of extinct or extant life on Mars. Atmospheric studies, analysis of subsurface material and regime, and the first attempt at in-situ radiometric dating of rocks on another planet make Beagle 2 unique among planetary missions. The lander is named after Darwin’s ship, H.M.S Beagle.
Observations of Galactic Magnetic Fields
Authors: Beck Rainer
Published: March 2016

Magnetic fields are anchored in gas clouds. Field lines are tangled in spiral arms, but highly regular between the arms. The similarity of pitch angles between gaseous and magnetic arms suggests a coupling between the density wave and the magnetic wave. Observations of large-scale patterns in Faraday rotation favour a dynamo origin of the regular fields. Fields in barred galaxies do not reveal the strong shearing shocks observed in the cold gas, but swing smoothly from the upstream region into the bar. Magnetic fields are important for the dynamics of gas clouds, for the formation of spiral structures, bars and halos, and for mass and angular momentum transport in central regions.
Galactic Dynamos
Authors: Moss David
Published: March 2016

There is a broad agreement between the predictions of galactic dynamo theory and observations; although there are still some unresolved difficulties, the theory appears to be robust. Now attention is turning from generic models to studies of particular features of the large-scale magnetic fields, and also to models for specific galaxies. The effects of noncircular flows, for example driven by the interaction of spiral arms and galactic bars with the dynamo, are of current interest.
Intergalactic Globular Clusters
Authors: West Michael J. , Côté Patrick , Ferguson Henry C. , Gregg Michael D. , Jordán Andrés , Marzke Ronald O. , Tanvir Nial R. , Hippel Ted von
Published: March 2016

We confirm and extend our previous detection of a population of intergalactic globular clusters in Abell 1185, and report the first discovery of an intergalactic globular cluster in the nearby Virgo cluster of galaxies. The numbers, colors and luminosities of these objects can place constraints on their origin, which in turn may yield new insights to the evolution of galaxies in dense environments.
Observations of Solar-Like Oscillations
Authors: Kjeldsen Hans , Bedding Timothy R.
Published: March 2016

The solar-like oscillations are oscillations that are expected to be excited by near-surface convection. Apart from the Sun itself, we now have a number of stars where p-mode solar-like oscillations have been detected. In this paper we present a short presentation of those recently discovered oscillations.
Binary Stars in the Local Group: The Playing Field
Authors: Mateo Mario L.
Published: March 2016

As an introduction to the stage on which Extragalactic Binaries exist I will present an overview of the stellar populations of the Local Group Galaxies. This will highlight the (few) similarities in the star formation histories of Local Group galaxies as well as the better-known variety that has been uncovered in recent studies. In the few cases where this is possible, the direct role of binaries in the interpretation of the star forming histories of these galaxies will be described. The possible role of binaries in helping to shape the star-formation history will be described more generally with some emphasis on the sorts of observations that can be carried out to investigate this more fully.
Chemistry of Collapse and Disk Accretion
Authors: Charnley S. B. , Rodgers S. D.
Published: March 2016

Recent results relevant for the survival and chemical alteration of interstellar material at the nebular accretion shock are summarised.
The Potential for Astronomy in Antarctica
Authors: Burton M. G.
Published: March 2016

The motivation for holding Special Session 2 at the 25th IAU GA is described, together with an outline of the rational for pursuing astronomy in Antarctica.
The AST/RO Survey of the Galactic Center Region
Authors: Stark Antony A.
Published: March 2016

AST/RO is a 1.7m diameter submillimeter-wave telescope at the geographic South Pole. A key AST/RO project is the mapping of CI and CO J = 4→3 and J = 7 → 6 emission from the inner Milky Way (Martin et al. 2003). These data are released for general use.
Compact Wide-Field Astronomical Telescopes for Dome C
Authors: Viotti Roberto F. ,   the TRT team
Published: March 2016

We describe our project for a small and compact telescope, based on the TRT design, for wide-field observations from Dome C on the Antarctic Plateau, and discuss the main scientific goals.
Longitudinal characterization of dysfunctional T cell-activation during human acute Ebola infection
Authors: Agrati C , Castilletti C , Casetti R , Sacchi A , Falasca L , Turchi F , Tumino N , Bordoni V , Cimini E , Viola D , Lalle E , Bordi L , Lanini S , Martini F , Nicastri E , Petrosillo N , Puro V , Piacentini M , Di Caro A , Kobinger G P , Zumla A , Ippolito G , Capobianchi M R
Published: March 2016

Data on immune responses during human Ebola virus disease (EVD) are scanty, due to limitations imposed by biosafety requirements and logistics. A sustained activation of T-cells was recently described but functional studies during the acute phase of human EVD are still missing. Aim of this work was to evaluate the kinetics and functionality of T-cell subsets, as well as the expression of activation, autophagy, apoptosis and exhaustion markers during the acute phase of EVD until recovery. Two EVD patients admitted to the Italian National Institute for Infectious Diseases, Lazzaro Spallanzani, were sampled sequentially from soon after symptom onset until recovery and analyzed by flow cytometry and ELISpot assay. An early and sustained decrease of CD4 T-cells was seen in both patients, with an inversion of the CD4/CD8 ratio that was reverted during the recovery period. In parallel with the CD4 T-cell depletion, a massive T-cell activation occurred and was associated with autophagic/apoptotic phenotype, enhanced expression of the exhaustion marker PD-1 and impaired IFN-gamma production. The immunological impairment was accompanied by EBV reactivation. The association of an early and sustained dysfunctional T-cell activation in parallel to an overall CD4 T-cell decline may represent a previously unknown critical point of Ebola virus (EBOV)-induced immune subversion. The recent observation of late occurrence of EBOV-associated neurological disease highlights the importance to monitor the immuno-competence recovery at discharge as a tool to evaluate the risk of late sequelae associated with resumption of EBOV replication. Further studies are required to define the molecular mechanisms of EVD-driven activation/exhaustion and depletion of T-cells.
Long non-coding RNA C2dat1 regulates CaMKIIδ expression to promote neuronal survival through the NF-κB signaling pathway following cerebral ischemia
Authors: Xu Q , Deng F , Xing Z , Wu Z , Cen B , Xu S , Zhao Z , Nepomuceno R , Bhuiyan M I H , Sun D , Wang Q J , Ji A
Published: March 2016

Increasing evidence has demonstrated a significant role of long non-coding RNAs (lncRNAs) in diverse biological processes. However, their functions in cerebral ischemia remain largely unknown. Through an lncRNA array analysis in a rat model of focal cerebral ischemia/reperfusion (I/R), we have identified CAMK2D-associated transcript 1 (C2dat1) as a novel I/R-induced lncRNA that regulated the expression of CaMKIIδ in murine models of focal cerebral ischemia. C2dat1 mRNA was upregulated in a time-dependent manner in mouse cortical penumbra after focal ischemic brain injury, which was accompanied by increased expression of CaMKIIδ at transcript and protein levels. The expression patterns of C2dat1 and CAMK2D were confirmed in mouse Neuro-2a cells in response to in vitro ischemia (oxygen-glucose deprivation/reoxygenation, OGD/R). Knockdown of C2dat1 resulted in a significant blockade of CaMKIIδ expression, and potentiated OGD/R-induced cell death. Mechanistically, reduced CaMKIIδ expression upon silencing C2dat1 inhibited OGD/R-induced activation of the NF-κB signaling pathway. Further analysis showed that the downregulation of IKKα and IKKβ expression and phosphorylation, and subsequent inhibition of IκBα degradation accounted for the inhibition of the NF-κB signaling activity caused by silencing C2dat1. In summary, we discovered a novel I/R-induced lncRNA C2dat1 that modulates the expression of CaMKIIδ to impact neuronal survival, and may be a potential target for therapeutic intervention of ischemic brain injury.
Pdcd4 restrains the self-renewal and white-to-beige transdifferentiation of adipose-derived stem cells
Authors: Bai Y , Shang Q , Zhao H , Pan Z , Guo C , Zhang L , Wang Q
Published: March 2016

The stemness maintenance of adipose-derived stem cells (ADSCs) is important for adipose homeostasis and energy balance. Programmed cell death 4 (Pdcd4) has been demonstrated to be involved in the development of obesity, but its possible roles in ADSC function and adipogenic capacity remain unclear. In this study, we demonstrate that Pdcd4 is a key controller that limits the self-renewal and white-to-beige transdifferentiation of ADSCs. Pdcd4 deficiency in mice caused stemness enhancement of ADSCs as evidenced by increased expression of CD105, CD90, Nanog and Oct4 on ADSCs, together with enhanced in situ proliferation in adipose tissues. Pdcd4 deficiency promoted proliferation, colony formation of ADSCs and drove more ADSCs entering the S phase accompanied by AKT activation and cyclinD1 upregulation. Blockade of AKT signaling in Pdcd4-deficient ADSCs led to a marked decline in cyclinD1, S-phase entry and cell proliferation, revealing AKT as a target for repressing ADSC self-renewal by Pdcd4. Intriguingly, depletion of Pdcd4 promoted the transdifferentiation of ADSCs into beige adipocytes. A reduction in lipid contents and expression levels of white adipocyte markers including C/EBPα, PPAR-γ, adiponectin and αP2 was detected in Pdcd4-deficient ADSCs during white adipogenic differentiation, substituted by typical beige adipocyte characteristics including small, multilocular lipid droplets and UCP1 expression. More lactate produced by Pdcd4-deficient ADSCs might be an important contributor to the expression of UCP1 and white-to-beige transdifferentiation. In addition, an elevation of UCP1 expression was confirmed in white adipose tissues from Pdcd4-deficient mice upon high-fat diet, which displayed increased energy expenditure and resistance to obesity as compared with wild-type obese mice. These findings provide evidences that Pdcd4 produces unfavorable influences on ADSC stemness, which contribute to adipose dysfunction, obesity and metabolic syndromes, thereby proposing Pdcd4 as a potential intervening target for regulating ADSC function.
Cigarette smoking and the oral microbiome in a large study of American adults
Authors: Wu Jing , Peters Brandilyn A , Dominianni Christine , Zhang Yilong , Pei Zhiheng , Yang Liying , Ma Yingfei , Purdue Mark P , Jacobs Eric J , Gapstur Susan M , Li Huilin , Alekseyenko Alexander V , Hayes Richard B , Ahn Jiyoung
Published: March 2016

Oral microbiome dysbiosis is associated with oral disease and potentially with systemic diseases; however, the determinants of these microbial imbalances are largely unknown. In a study of 1204 US adults, we assessed the relationship of cigarette smoking with the oral microbiome. 16S rRNA gene sequencing was performed on DNA from oral wash samples, sequences were clustered into operational taxonomic units (OTUs) using QIIME and metagenomic content was inferred using PICRUSt. Overall oral microbiome composition differed between current and non-current (former and never) smokers (P<0.001). Current smokers had lower relative abundance of the phylum Proteobacteria (4.6%) compared with never smokers (11.7%) (false discovery rate q=5.2 × 10−7), with no difference between former and never smokers; the depletion of Proteobacteria in current smokers was also observed at class, genus and OTU levels. Taxa not belonging to Proteobacteria were also associated with smoking: the genera Capnocytophaga, Peptostreptococcus and Leptotrichia were depleted, while Atopobium and Streptococcus were enriched, in current compared with never smokers. Functional analysis from inferred metagenomes showed that bacterial genera depleted by smoking were related to carbohydrate and energy metabolism, and to xenobiotic metabolism. Our findings demonstrate that smoking alters the oral microbiome, potentially leading to shifts in functional pathways with implications for smoking-related diseases.
Genetic and life-history traits associated with the distribution of prophages in bacteria
Authors: Touchon Marie , Bernheim Aude , Rocha Eduardo P C
Published: March 2016

Nearly half of the sequenced bacteria are lysogens and many of their prophages encode adaptive traits. Yet, the variables driving prophage distribution remain undetermined. We identified 2246 prophages in complete bacterial genomes to study the genetic and life-history traits associated with lysogeny. While optimal growth temperatures and average cell volumes were not associated with lysogeny, prophages were more frequent in pathogens and in bacteria with small minimal doubling times. Their frequency also increased with genome size, but only for genomes smaller than 6 Mb. The number of spacers in CRISPR-Cas systems and the frequency of type III systems were anticorrelated with prophage frequency, but lysogens were more likely to encode type I and type II systems. The minimal doubling time was the trait most correlated with lysogeny, followed by genome size and pathogenicity. We propose that bacteria with highly variable growth rates often encounter lower opportunity costs for lysogeny relative to lysis. These results contribute to explain the paucity of temperate phages in certain bacterial clades and of bacterial lysogens in certain environments. They suggest that genetic and life-history traits affect the contributions of temperate phages to bacterial genomes.
Neogenin recruitment of the WAVE regulatory complex maintains adherens junction stability and tension
Authors: Lee Natalie K. , Fok Ka Wai , White Amanda , Wilson Nicole H. , O’Leary Conor J. , Cox Hayley L. , Michael Magdalene , Yap Alpha S. , Cooper Helen M.
Published: March 2016

To maintain tissue integrity during epithelial morphogenesis, adherens junctions (AJs) must resist the mechanical stresses exerted by dynamic tissue movements. Junctional stability is dependent on actomyosin contractility within the actin ring. Here we describe a novel function for the axon guidance receptor, Neogenin, as a key component of the actin nucleation machinery governing junctional stability. Loss of Neogenin perturbs AJs and attenuates junctional tension. Neogenin promotes actin nucleation at AJs by recruiting the Wave regulatory complex (WRC) and Arp2/3. A direct interaction between the Neogenin WIRS domain and the WRC is crucial for the spatially restricted recruitment of the WRC to the junction. Thus, we provide the first example of a functional WIRS–WRC interaction in epithelia. We further show that Neogenin regulates cadherin recycling at the AJ. In summary, we identify Neogenin as a pivotal component of the AJ, where it influences both cadherin dynamics and junctional tension.
Oxygen depletion recorded in upper waters of the glacial Southern Ocean
Authors: Lu Zunli , Hoogakker Babette A. A. , Hillenbrand Claus-Dieter , Zhou Xiaoli , Thomas Ellen , Gutchess Kristina M. , Lu Wanyi , Jones Luke , Rickaby Rosalind E. M.
Published: March 2016

Oxygen depletion in the upper ocean is commonly associated with poor ventilation and storage of respired carbon, potentially linked to atmospheric CO2 levels. Iodine to calcium ratios (I/Ca) in recent planktonic foraminifera suggest that values less than ∼2.5 μmol mol−1 indicate the presence of O2-depleted water. Here we apply this proxy to estimate past dissolved oxygen concentrations in the near surface waters of the currently well-oxygenated Southern Ocean, which played a critical role in carbon sequestration during glacial times. A down-core planktonic I/Ca record from south of the Antarctic Polar Front (APF) suggests that minimum O2 concentrations in the upper ocean fell below 70 μmol kg−1 during the last two glacial periods, indicating persistent glacial O2 depletion at the heart of the carbon engine of the Earth’s climate system. These new estimates of past ocean oxygenation variability may assist in resolving mechanisms responsible for the much-debated ice-age atmospheric CO2 decline.
Genome-based microbial ecology of anammox granules in a full-scale wastewater treatment system
Authors: Speth Daan R. , in ’t Zandt Michiel H. , Guerrero-Cruz Simon , Dutilh Bas E. , Jetten Mike S. M.
Published: March 2016

Partial-nitritation anammox (PNA) is a novel wastewater treatment procedure for energy-efficient ammonium removal. Here we use genome-resolved metagenomics to build a genome-based ecological model of the microbial community in a full-scale PNA reactor. Sludge from the bioreactor examined here is used to seed reactors in wastewater treatment plants around the world; however, the role of most of its microbial community in ammonium removal remains unknown. Our analysis yielded 23 near-complete draft genomes that together represent the majority of the microbial community. We assign these genomes to distinct anaerobic and aerobic microbial communities. In the aerobic community, nitrifying organisms and heterotrophs predominate. In the anaerobic community, widespread potential for partial denitrification suggests a nitrite loop increases treatment efficiency. Of our genomes, 19 have no previously cultivated or sequenced close relatives and six belong to bacterial phyla without any cultivated members, including the most complete Omnitrophica (formerly OP3) genome to date.
Identification of chemicals that mimic transcriptional changes associated with autism, brain aging and neurodegeneration
Authors: Pearson Brandon L. , Simon Jeremy M. , McCoy Eric S. , Salazar Gabriela , Fragola Giulia , Zylka Mark J.
Published: March 2016

Environmental factors, including pesticides, have been linked to autism and neurodegeneration risk using retrospective epidemiological studies. Here we sought to prospectively identify chemicals that share transcriptomic signatures with neurological disorders, by exposing mouse cortical neuron-enriched cultures to hundreds of chemicals commonly found in the environment and on food. We find that rotenone, a pesticide associated with Parkinson’s disease risk, and certain fungicides, including pyraclostrobin, trifloxystrobin, famoxadone and fenamidone, produce transcriptional changesin vitrothat are similar to those seen in brain samples from humans with autism, advanced age and neurodegeneration (Alzheimer’s disease and Huntington’s disease). These chemicals stimulate free radical production and disrupt microtubules in neurons, effects that can be reduced by pretreating with a microtubule stabilizer, an antioxidant, or with sulforaphane. Our study provides an approach to prospectively identify environmental chemicals that transcriptionally mimic autism and other brain disorders.
Osteosarcoma: prognosis plateau warrants retinoblastoma pathway targeted therapy
Authors: Ballatori Sarah E , Hinds Philip W
Published: March 2016

Osteosarcoma (OS) is the most common primary bone cancer in children and adolescents, affecting ~560 young patients in the United States annually. The term OS describes a diverse array of subtypes with varying prognoses, but the majority of tumors are high grade and aggressive. Perhaps because the true etiology of these aggressive tumors remains unknown, advances in OS treatment have reached a discouraging plateau, with only incremental improvements over the past 40 years. Thus, research surrounding the pathogenesis of OS is essential, as it promises to unveil novel therapeutic targets that can attack tumor cells with greater specificity and lower toxicity. Among the candidate molecular targets in OS, the retinoblastoma (RB) pathway demonstrates the highest frequency of inactivation and thus represents a particularly promising avenue for molecular targeted therapy. This review examines the present thinking and practices in OS treatment and specifically highlights the relevance of the RB pathway in osteosarcomagenesis. Through further investigation into RB pathway-related novel therapeutic targets, we believe that a near-term breakthrough in improved OS prognosis is possible.
The influence of polymer purification on the efficiency of poly(3-hexylthiophene):fullerene organic solar cells
Authors: Bannock James H. , Treat Neil D. , Chabinyc Michael , Stingelin Natalie , Heeney Martin , de Mello John C.
Published: March 2016

We report the influence of different polymer purification procedures on the photovoltaic performance of bulk heterojunction solar cells formed from binary blends of poly(3-hexylthiophene) (P3HT) and fullerenes. Selective Soxhlet extractions and metal scavenging agents were used to remove residual monomer, magnesium salt by-products and catalyst from high-weight P3HT (Mw 121 kg/mol, PDI 1.8, RR 99%) synthesised by the Grignard metathesis (GRIM) polymerization route. Using phenyl-C61-butyric acid methyl ester (PC60BM) as an electron acceptor, we observed an increase in average power conversion efficiency from 2.3 to 4.8% in going from crude to fully purified material. Using indene-C60 bisadduct (IC60BA) in place of PC60BM, we observed a further increase to an average value of 6.6% - high for a bulk heterojunction formed from a binary blend of P3HT and C60 fullerene derivatives.
Structure Based Docking and Molecular Dynamic Studies of Plasmodial Cysteine Proteases against a South African Natural Compound and its Analogs
Authors: Musyoka Thommas M. , Kanzi Aquillah M. , Lobb Kevin A. , Tastan Bishop Özlem
Published: March 2016

Identification of potential drug targets as well as development of novel antimalarial chemotherapies with unique mode of actions due to drug resistance by Plasmodium parasites are inevitable. Falcipains (falcipain-2 and falcipain-3) of Plasmodium falciparum, which catalyse the haemoglobin degradation process, are validated drug targets. Previous attempts to develop peptide based drugs against these enzymes have been futile due to the poor pharmacological profiles and susceptibility to degradation by host enzymes. This study aimed to identify potential non-peptide inhibitors against falcipains and their homologs from other Plasmodium species. Structure based virtual docking approach was used to screen a small non-peptidic library of natural compounds from South Africa against 11 proteins. A potential hit, 5α-Pregna-1,20-dien-3-one (5PGA), with inhibitory activity against plasmodial proteases and selectivity on human cathepsins was identified. A 3D similarity search on the ZINC database using 5PGA identified five potential hits based on their docking energies. The key interacting residues of proteins with compounds were identified via molecular dynamics and free binding energy calculations. Overall, this study provides a basis for further chemical design for more effective derivatives of these compounds. Interestingly, as these compounds have cholesterol-like nuclei, they and their derivatives might be well tolerated in humans.
Dynamic in situ observation of voltage-driven repeatable magnetization reversal at room temperature
Authors: Gao Ya , Hu Jia-Mian , Nelson C. T. , Yang T. N. , Shen Y. , Chen L. Q. , Ramesh R. , Nan C. W.
Published: March 2016

Purely voltage-driven, repeatable magnetization reversal provides a tantalizing potential for the development of spintronic devices with a minimum amount of power consumption. Substantial progress has been made in this subject especially on magnetic/ferroelectric heterostructures. Here, we report the in situ observation of such phenomenon in a NiFe thin film grown directly on a rhombohedral Pb(Mg1/3Nb2/3)0.7Ti0.3O3(PMN-PT) ferroelectric crystal. Under a cyclic voltage applied perpendicular to the PMN-PT without a magnetic field, the local magnetization of NiFe can be repetitively reversed through an out-of-plane excursion and then back into the plane. Using phase field simulations we interpret magnetization reversal as a synergistic effect of the metastable ferroelastic switching in the PMN-PT and an electrically rotatable local exchange bias field arising from the heterogeneously distributed NiO clusters at the interface.
Transcriptome analysis in different rice cultivars provides novel insights into desiccation and salinity stress responses
Authors: Shankar Rama , Bhattacharjee Annapurna , Jain Mukesh
Published: March 2016

Drought and salinity are the major environmental factors that affect rice productivity. Comparative transcriptome analysis between tolerant and sensitive rice cultivars can provide insights into the regulatory mechanisms involved in these stress responses. In this study, the comparison of transcriptomes of a drought-tolerant [Nagina 22 (N22)] and a salinity-tolerant (Pokkali) rice cultivar with IR64 (susceptible cultivar) revealed variable transcriptional responses under control and stress conditions. A total of 801 and 507 transcripts were exclusively differentially expressed in N22 and Pokkali rice cultivars, respectively, under stress conditions. Gene ontology analysis suggested the enrichment of transcripts involved in response to abiotic stress and regulation of gene expression in stress-tolerant rice cultivars. A larger number of transcripts encoding for members of NAC and DBP transcription factor (TF) families in N22 and members of bHLH and C2H2 TF families in Pokkali exhibited differential regulation under desiccation and salinity stresses, respectively. Transcripts encoding for thioredoxin and involved in phenylpropanoid metabolism were up-regulated in N22, whereas transcripts involved in wax and terpenoid metabolism were up-regulated in Pokkali. Overall, common and cultivar-specific stress-responsive transcripts identified in this study can serve as a helpful resource to explore novel candidate genes for abiotic stress tolerance in rice.
Reconstructing the complex evolutionary history of mobile plasmids in red algal genomes
Authors: Lee JunMo , Kim Kyeong Mi , Yang Eun Chan , Miller Kathy Ann , Boo Sung Min , Bhattacharya Debashish , Yoon Hwan Su
Published: March 2016

The integration of foreign DNA into algal and plant plastid genomes is a rare event, with only a few known examples of horizontal gene transfer (HGT). Plasmids, which are well-studied drivers of HGT in prokaryotes, have been reported previously in red algae (Rhodophyta). However, the distribution of these mobile DNA elements and their sites of integration into the plastid (ptDNA), mitochondrial (mtDNA), and nuclear genomes of Rhodophyta remain unknown. Here we reconstructed the complex evolutionary history of plasmid-derived DNAs in red algae. Comparative analysis of 21 rhodophyte ptDNAs, including new genome data for 5 species, turned up 22 plasmid-derived open reading frames (ORFs) that showed syntenic and copy number variation among species, but were conserved within different individuals in three lineages. Several plasmid-derived homologs were found not only in ptDNA but also in mtDNA and in the nuclear genome of green plants, stramenopiles, and rhizarians. Phylogenetic and plasmid-derived ORF analyses showed that the majority of plasmid DNAs originated within red algae, whereas others were derived from cyanobacteria, other bacteria, and viruses. Our results elucidate the evolution of plasmid DNAs in red algae and suggest that they spread as parasitic genetic elements. This hypothesis is consistent with their sporadic distribution within Rhodophyta.