bluuebunny/crossref_metadata_2025 huggingface dataset:
SPATIAL GENETIC STRUCTURE IN POPULATIONS OF HOSTA CAPITATA AND HOSTA MINOR (LILIACEAE)
Authors: CHUNG MYONG GI , Park Ki Bae
Published: April 2013

The spatial distribution of genotypes was examined in each of two populations ofHosta capitataandH. minorusing spatial autocorrelation analysis of enzyme polymorphisms. Although these two species have a similar life history and similar ecological traits, this study indicates that the pattern of spatial genetic distribution in the species differed. The percentage of significant Moran'sIfor all distance classes differs (20% and 14% inH. capitata;33% and 53% inH. minor).Significant positive Moran'sIvalues were detected in the shorter distance classes forH. capitata(distance class 1–3, 0–4.5 m), whereas these values forH. minorwere observed in longer distance classes (distance classes 5–6, 0–10.4 m). Approximate minimum patch area forH, capitata(7–20 m2) is smaller than that ofH. minor(38–78 m2). As the weights of seeds are nearly the same in both species and seedlings grow near maternal individuals in both species, and gene flow via seed is expected to be at the same level, the observed difference in patterns of spatial genetic distribution may in part be due to the differences between both species in terms of the extent of gene flow via pollen dispersal, selective forces, and other unknown factors of their reproductive biology.
ESTIMATING HERITABILITY OF FAMILIES DERIVED FROM SINGLE PLANTS AT AN ADVANCED GENERATION OF SELF-FERTILIZING SPECIES: DEVELOPING GENERAL FORMULAS AND ESTIMATING SPRING WHEAT TRAITS
Authors: Beharav Alex , Pinthus J. Moshe , Cahaner Avigdor
Published: April 2013

Genetic expectations of total genetic variance, and between-family and within-family variance components were developed for any given generation (Fn) derived from single selfed plants of an earlier generation (Fk). A formula to estimate the heritability (h2) in any desired generation (Fn) was developed on the basis of these expectations. This formula estimates the value of the genetic variance from the phenotypic variance adjusted to the F2 generation. Heritability estimates of culm length, heading date, and mean grain weight from two populations of F6 families, each derived from a single F5 plant, were computed using this formula, and a formula which estimates the value of the genetic variance from the phenotypic variance in the Fn generation (“Fn estimates”). The FN h2 estimates at F6 were always higher than those adjusted to F2 variance, due to the increase in additive variance and the reduction in dominance variance.
VEGETATION-ENVIRONMENT RELATIONSHIPS IN THE ULTRAMAFIC AREA OF MONTE FERRATO, ITALY
Authors: Chiarucci Alessandro , Riccucci Michele , Celesti Carlo , De Dominicis Vincenzo
Published: April 2013

Relationships between some environmental features and species composition and abundance of grassland and dwarf shrub vegetation were investigated on Monte Ferrato, one of the best known ultramafic (serpentine) sites of Italy. The main aim was to test the importance of the available fraction of soil metals in causing the typical infertility of ultramafic soils. The physical and chemical features of soil were determined for each plot in which species composition and cover were recorded. The plots were classified by cluster analysis and ANOVA was applied to compare the environmental variables of groups of plots. Canonical Correspondence Analysis (CCA) was used to detect the principle factors related to the gradient of species composition within the plant communities. It was found that the grassland and dwarf vegetation of Monte Ferrato is not negatively influenced by soil content of nickel and other metals. Pine canopy cover, which provides additional nutrient input and protects against erosion, was found to be important for evolution of the garigues into grasslands. The evolution of grassland turf induced the retention of higher levels of exchangeable cations, including potentially toxic metals, in the evolved soil.
POSSIBLE ROLE OF BIOGENIC CRUSTS IN PLANT SUCCESSION ON THE SHARON SAND DUNES, ISRAEL
Authors: Kutiel Pua
Published: April 2013

Sand dunes in the coastal plain are subjected to stabilization processes due to the increase of vegetation cover of both vascular and non-vascular plants (e.g., mosses, lichens, fungi, and cyanobacteria). The non-vascular plants form intimate associations with surface soils known as biogenic crusts. These crusts play a major role in pedologic and overland geomorphic processes. The spatial distribution of biogenic crusts on semi-stabilized and stabilized sand dunes of the Sharon coastal plain, and their effect on organic matter content and water regime in the soil, were analyzed. Results indicated that a small and discontinuous area of the semi-stabilized sand dunes was covered by biogenic crusts. This crust was mainly composed of mosses and was concentrated beneath shrubs. Nevertheless, 88% of the stabilized sand dunes were covered with biogenic crusts composed mainly of cyanobacteria. The levels of organic matter and the water content in the upper soil layer (0–2 cm) of the crusted sand were significantly higher than levels in the uncrusted sand. The water regime in the upper soil layer covered with mosses was higher than that covered by cyanobacteria crust. The water regime in the soil determined by the biogenic crust may play an important role in the vascular plant succession of the sand dunes.
ANNUAL VEGETATION OF THE COASTAL SAND DUNES OF THE NORTHERN SHARON, ISRAEL
Authors: Kutiel Pua
Published: April 2013

This study aims at describing and characterizing the annual vegetation of the northern Sharon sand dunes and its relationship with organic matter content, texture, and field capacity of the upper soil layer (0–30 cm). Eleven annual plant units were determined. These units differ in plant composition, plant density, total biomass, species richness, and species diversity in correspondence with the upper soil layer properties. The plant biomass and the species richness increased with the increase of organic matter content and field capacity. However, species diversity and the average number of species per sampling square increased from shifting to semi- stabilized sand dunes, and then decreased at the stabilized dunes where the organic matter and field capacity were high. Changes in the annual vegetation gradient, together with that of the soil properties, provided a detailed description of the succession scenario on the sand dunes of this area.
SPECIES DIVERSITY IN THE TRIBE AGARICEAE PAT. (HIGHER BASIDIOMYCETES) OF ISRAEL MYCOBIOTA
Authors: Wasser Solomon P.
Published: April 2013

A taxonomic study of the tribe Agariceae Pat. (Higher Basidiomycetes) of Israel is given. The tribe Agariceae is represented by 38 species and infraspecific taxa related to 3 genera:MelanophyllumVel.,AgaricusL: Fr. emend. Karst., andGyrophragmiumMont. Three species:Agaricus boniiS. Wasser,A. nevoiS. Wasser, andA. herinkiiS. Wasser, were described as new for science earlier.Melanophyllum haematospermum(Bull: Fr.) Kreisel,Agaricus aestivalisMoell. var.flavotacta(Moell.) Moell.,A. bitorquis(Quél.) Sacc.,A. campestrisL: Fr. Var.floccipes(Moell.) Pil.,A. geesteraniiBas et Heinem.,A. gennadii(Chat. et Bond.) P.D. Orton var.microsporus(Bohus) S. Wasser,A. impudicus(Rea) Pil.,A. praeclaresquamosusFreeman,A. pequinii(Bond.) Konr. et Maubl.,A. silvaticusSchaeff. varpallensPil.,A. xanthodermaGen. var.lepiotoidesR. Mre,A. vaporarius(Pers.) Cappelli, andA. lanipes(Moell. et J. Schaeff.) Sing, are new for Israel and some of them for Asia or for the Middle East. Synonyms, locations, and dates of collection in Israel, peculiarities, general distribution, as well as taxonomic remarks to some taxa are given.
ROLE OF CHARRED WOOD, HEAT-SHOCK, AND LIGHT IN GERMINATION OF POSTFIRE PHRYGANA SPECIES FROM THE EASTERN MEDITERRANEAN BASIN
Authors: Keeley E. Jon , Babr-Keeley Melanie
Published: April 2013

Seeds of 22 species collected from recently burned phrygana were tested for their response to fire-type cues of charred wood and heat-shock. All Cistus species were stimulated by brief heat-shock, as shown in previous studies; however, none responded to charred wood. Only one of the 22 species was stimulated by charred wood, and only in dark-inhibited seeds, and this response did not occur in the light. The lack of charred-wood-induced germination is in contrast to the substantial proportion of species with this germination response reported for mediterranean-type vegetation in California, the Cape region of South Africa, and Western Australia. Phrygana has many species with heat-shock-stimulated germination, primarily in the Fabaceae and Cistaceae. This germination cue is widespread in these two families, thus, the presence of heat-shock-stimulated germination is a result of homologous, rather than covergent, adaptations in mediterranean-climate ecosystems. Germination response to light was not randomly distributed with respect to fire-type response. Heat-shock-stimulated species were almost uniformly light neutral, in contrast to more opportunistic colonizing species with non-refractory seeds, in which half of the species responded positively or negatively to light.
NITROGEN FIXATION AND CARBON METABOLISM IN VICIA FABA ROOT NODULES OVER ONTOGENY
Authors: Ocaña Antonio , Caba Juan Manuel , Ligero Francisco , Lluch Carmen
Published: April 2013

The evolution of growth, nodulation, nitrogen fixation, and activities of root-nodule enzymes related to sucrose breakdown (sucrose synthase, alkaline invertase), pentose phosphate pathway (glucose-6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase), malate dehydrogenase, phosphoenolpyruvate carboxylase, and NADP-dependent isocitrate dehydrogenase, were followed over the complete life-cycle of faba bean in a growth chamber. The aim was to study the ontogenic changes of these parameters to obtain information on the carbon metabolism in nodules ofVicia faba, an amide-exporting legume. The maximum values of the relative growth rate and the specific acetylene-reducing activity were registered during the vegetative period. At pod-filling, the specific and total acetylene-reducing activity per plant declined in parallel with the enzyme activities of carbon metabolism. Contrary to reports for other legume species, inV. fabaroot nodule activity of sucrose synthase exceeded alkaline invertase values by 2-fold or more during the vegetative period. The activity of the two enzymes was similar at flowering and pod formation. The enzymes of carbon metabolism registered two maxima, one before and one after a trough (day 32), which marked the change from the vegetative to the reproductive period.
MORPHOLOGICAL AND ANATOMICAL INVESTIGATIONS OF BALLOTA NIGRA L. SUBSP. ANATOLICA P.H. DAVIS USED AS FOLK MEDICINE
Authors: Ezer Nurten , Şahin F.P , Toker M.C
Published: April 2013

No previous significant and detailed botanical study exists on Ballota nigra L. subsp. anatolica P.H. Davis, which is endemic in Turkey and is used in folk medicine. B. nigra has been reported as Marrubium nigrum and it is difficult to separate from Stachys. The aim of this study is to provide information on the anatomical, morphological, and cytological properties of Ballota nigra subsp. anatolica. Phytochemical screening methods were also applied for identifying the major chemical groups in this species. Chromosome shapes and chromosome number were determined. Flavonoids, phenylpropanoid heterosides, tannins, saponins, volatile oil, terpenic compounds, and sugars were detected in the aerial parts of the plant.
SALT/WATER RELATIONSHIPS IN MANGROVES
Authors: Hanagata Nobutaka , Takemura Taro , Karube Isao , Dubinsky Zvy
Published: April 2013

Mangroves form extensive, unique communities in tropical coastal areas and tidal lowlands, dominating 60–75% of tropical shorelines. The aim of the present review is to summarize the current knowledge concerning the mechanisms underlying the most striking feature of these plants—their unique ability to obtain water from the surrounding sea. Mangroves are thought to accomplish this by rejecting potentially harmful salts. Some species actively excrete those salts leaking into the plant by means of specialized salt glands in their leaves. Mangroves are rooted in anaerobic soils, a condition giving rise to the spectacular aerial roots, such as pneumatophores and stilt roots, characteristic of mangroves, that provide oxygen to submerged tissues.

We shall also discuss recent studies that have focused on physiological issues in mangroves, such as oscillatory behavior of their stomata, the structure and function of salt glands, and the compatible solutes in their leaves, which balance the osmotic pressure of the seawater. Salinity effects on their germination, distribution, CO2assimilation, respiration, and the functioning of some of their enzymes have also been examined.

Finally, we shall draw attention to open questions related to the salt and water regime of mangroves and the underlying mechanisms responsible for their remarkable success in a hostile environment.
ANATOMICAL STUDIES ON THE SCILLA VERNA (HYACINTHACEAE) COMPLEX
Authors: Almeida Da Silva Rubim M. , Rosselló A. Josep
Published: April 2013

The phytodermology and leaf and scape anatomy were studied in wild populations of theScilla vernacomplex (Scilla vernaHudson,S. rambureiBoiss,S. odorataLink,S. monophyllosLink.,S. pauiLacaita, andS. merinoiOrtiz et al.) and several unrelated species (Scilla peruvianaL.,S. hyacinthoidesL.,S. lilio-hyacinthusL., andS. obtusifoliaPoiret) in order to determine diagnostic characters to be used in intertaxa relationships. With the exception of leaf shape transection, all examined characters show little variation within taxa. Of the characters examined, those that show discrete variation between the studied taxa are the presence of trichomes, heterogeneity of chlorenchyma, presence of mucilaginous cavities, and epidermal extensions of the leaf margins. The close anatomical similarity observed between theScillataxa precludes its broad use for diagnosis. Within the complex, onlyScilla monophyllosandS. pauicould be distinguished by the anatomical features. No clear relationship has arisen between leaf stomatal measurements and ploidy level of the taxa.
ALGAL VEGETATION IN THE ELAT CORAL REEF RESERVE
Authors: Lundberg Barbro , Popper Nurit
Published: April 2013

During 1993–1996, algal vegetation was studied in three stations in Elat: two stations in the Hof Almog Nature Reserve and a third station at Taba, further south. In the Hof Almog stations, filamentous turf comprised more than half of the algal vegetation, macroalgae were scarce except for Lobophora variegata and crustose red algae, and total algal cover was low. In Taba, cover by macroalgae, e.g., Cystoseira myrica and Sargassum spp., and total algal cover was higher than in Hof Almog. Around the world, Cystoseira and Sargassum have disappeared or decreased in polluted areas. The almost total absence of these genera in the Hof Almog stations, in contrast to their ample occurrence at Taba, indicates pollution in Hof Almog but less in Taba. Numerous species found in earlier studies are absent in Elat, while other species are recorded for the first time in the present study.
EFFECTS OF PB2+ ON ROOT GROWTH, CELL DIVISION, AND NUCLEOLUS OF BRASSICA JUNCEA L.
Authors: Jiang Wusheng , Liu Donghua
Published: April 2013

The effects of different concentrations (10−5-10−2M) of lead nitrate on root growth and nucleoli in root tip cells of Brassica juncea L. were investigated. The results showed that lead nitrate has a stimulatory effect on root growth at lower concentrations, and an inhibitory effect at higher concentrations. Pb has toxic effects on chromosomal morphology, including c-mitosis and anaphase bridges, and on nucleoli, causing some particulate silver-stained material scattered in the nuclei and inducing irregularly shaped nucleoli. Once the nucleolus was affected, the root growth almost or completely stopped.
EFFECTS OF DIFFERENT PHYSIOCHEMICAL FACTORS ON REGENERATION OF CYMBOPOGON POLYNEUROS STAPF VIA CALLUS CULTURE AND SUBSEQUENT CHROMOSOMAL STABILITY
Authors: Das Anath Bandhu
Published: April 2013

In vitro regeneration of Cymbopogon polyneuros Stapf was obtained through callus culture using leaf base, node, and root as explants. Callus was induced from different explants with 2–5 mg/1 α-naphthalene acetic acid (NAA) and 1–2 mg/1 kinetin in Murashige and Skoog's (MS) basal medium. High frequency shoots were noticed from leaf-base callus supplemented with 3.5 mg/1 6-benzylaminopurine (BA), L-arginine, adenine, and a low level of NAA (0.2 mg/1). About 80–85 shoot buds were obtained from ca. 200 mg of callus per culture. The individual shoots produced root in the presence of 0.5–3 mg/1 indole 3-butyric acid or its potassium salt. Regenerated plants were cytologically and phenotypically stable. Regenerants were transplanted into soil and subsequently transferred to the field.
EFFECTS OF MELOIDOGYNE INCOGNITA, FUSARIUM OXYSPORUM F.SP. PISI, RHIZOBIUM SP., AND DIFFERENT SOIL TYPES ON GROWTH, CHLOROPHYLL, AND CAROTENOID PIGMENTS OF PEA
Authors: Siddiqui Zaki A. , Mir Riaz A. , Mahmood Irshad
Published: April 2013

The effects ofMeloidogyne incognita, Fusarium oxysporumf.sp.pisi, Rhizobiumsp., and different soil types on growth and chlorophyll and carotenoid pigments of pea were examined in single, simultaneous, and sequential inoculations. Soil with a 3:1 (v:v) clay:sand ratio produced the most plant growth and the largest concentrations of chlorophyll and carotenoid pigments when compared with the other soil types.Meloidogyne incognitaandF. oxysporumalone caused similar reductions in plant growth and concentrations of chlorophyll and carotenoid pigments while inoculation of the latter pathogen induced wilt symptoms.M. incognitaandF. oxysporuminteracted to show severe wilt symptoms compared withF. oxysporumalone. In single inoculation,Rhizobiumsp. increased plant growth and chlorophyll and carotenoid pigment concentrations while its inoculation with pathogens reduced damage caused by them. Inoculation ofRhizobiumsp. prior to pathogens was more effective in reducing damage than simultaneous inoculation. Inoculation of the pathogens prior toRhizobiumsp. resulted in more damage than simultaneous inoculation.F. oxysporumandRhizobiumsp. decreased nematode multiplication. The severity of wilt disease was greatest in 1:3 and 0:4 clay:sand ratio, while least in 3:1 clay:sand mixture.
NUCLEATED XYLEM FIBERS IN SOME INDIAN SPECIES
Authors: S. Rajput Kishore , Rao K.S.
Published: April 2013

Xylem fibers were found to have retained their nucleus in 27 species of 17 genera. These fibers were characterized by thick lignified walls with narrow lumen and tapering ends. Their length and width varied among the species studied and were greatest in Phyllanthes emblica Linn. and least in Antigonon leptopus H. & A. Depending on the species, the fibers were either septate or nonseptate. Each compartment of the septate fibers was accompanied by a single nucleus. The nuclei of these fibers were oval to oblong or fusiform in shape. Accumulation of starch in the lumina of the nucleated fibers was a common feature in all the species. Occurrence of nucleated fibers and its possible significance is discussed.
ZYGOTIC EMBRYO CULTURE OF TAXUS CHINESIS VAR. MAIREI AND PLANT REGENERATION THROUGH ORGANOGENESIS
Authors: Xie Deyu , Guo Zhongchen
Published: April 2013

When different media were compared for their effect on zygotic embryo culture, DCR was found more effective than MS medium. From these embryos, adventitious bud induction was achieved by optimizing formular conditions as described in this paper. Adventitious buds were formed from calli derived from hypocotyls of germinated embryos. Finally, adventitious roots were induced and complete plantlets were obtained.
An investigation into the psychometric properties of the CORE‐OM in patients with eating disorders
Authors: Jenkins Paul E. , Turner Hannah M.
Published: April 2013

Aim: The current study aimed to explore the psychometric properties of the CORE‐OM (Clinical Outcomes in Routine Evaluation – Outcome Measure) when used in an eating disorder sample. Method: The CORE‐OM was administered at assessment to 360 individuals referred to an eating disorders service. Principal component analysis was conducted to look at the psychometric structure of the CORE‐OM, and psychometric properties were investigated using analyses of reliability and validity. Results: Analyses of the psychometric structure suggested a three‐component solution reflecting negatively worded, positively worded and risk items. The CORE‐OM showed good acceptability, acceptable internal and test‐retest reliabilities, as well as good convergent and known groups validity. Conclusions: The results of the current study support the CORE‐OM as a reliable and valid measure for assessing psychological distress in eating disorders.
Attributable Burden of Hospital-OnsetClostridium difficileInfection: A Propensity Score Matching Study
Authors: Tabak Ying P. , Zilberberg Marya D. , Johannes Richard S. , Sun Xiaowu , McDonald L. Clifford
Published: April 2013

Objective.

To determine the attributable in-hospital mortality, length of stay (LOS), and cost of hospital-onsetClostridium difficileinfection (HO-CDI).

Design.

Propensity score matching.

Setting.

Six Pennsylvania hospitals (2 academic centers, 1 community teaching facility, and 3 community nonteaching facilities) contributing data to a clinical research database.

Patients.

Adult inpatients between 2007 and 2008.

Methods.

We defined HO-CDI in adult inpatients as a positiveC. difficiletoxin assay result from a specimen collected more than 48 hours after admission and more than 8 weeks following any previous positive result. We developed an HO-CDI propensity model and matched cases with noncases by propensity score at a 1 : 3 ratio. We further restricted matching within the same hospital, within the same principal disease group, and within a similar length of lead time from admission to onset of HO-CDI.

Results.

Among 77,257 discharges, 282 HO-CDI cases were identified. The propensity score-matched rate was 90%. Compared with matched noncases, HO-CDI patients had higher mortality (11.8% vs 7.3%;P<.05), longer LOS (median [interquartile range (IQR)], 12 [9–21] vs 11 [8–17] days;P< .01), and higher cost (median [IQR], $20,804 [$ll,059-$38,429] vs $16,634 [$9,413–$30,319];P< .01). The attributable effect of HO-CDI was 4.5% (95% confidence interval [CI], 0.2%–8.7%;P<.05) for mortality, 2.3 days (95% CI, 0.9–3.8;P<.01) for LOS, and $6,117 (95% CI, $1,659–$10,574;P<.01) for cost.

Conclusions.

Patients with HO-CDI incur additional attributable mortality, LOS, and cost burden compared with patients with similar primary clinical condition, exposure risk, lead time of hospitalization, and baseline characteristics.
Network-guided sparse regression modeling for detection of gene-by-gene interactions
Authors: Lu Chen , Latourelle Jeanne , O’Connor George T. , Dupuis Josée , Kolaczyk Eric D.
Published: April 2013

Motivation: Genetic variants identified by genome-wide association studies to date explain only a small fraction of total heritability. Gene-by-gene interaction is one important potential source of unexplained total heritability. We propose a novel approach to detect such interactions that uses penalized regression and sparse estimation principles, and incorporates outside biological knowledge through a network-based penalty.

Results: We tested our new method on simulated and real data. Simulation showed that with reasonable outside biological knowledge, our method performs noticeably better than stage-wise strategies (i.e. selecting main effects first, and interactions second, from those main effects selected) in finding true interactions, especially when the marginal strength of main effects is weak. We applied our method to Framingham Heart Study data on total plasma immunoglobulin E (IgE) concentrations and found a number of interactions among different classes of human leukocyte antigen genes that may interact to influence the risk of developing IgE dysregulation and allergy.

Availability: The proposed method is implemented in R and available at http://math.bu.edu/people/kolaczyk/software.html.

Contact:  chenlu@bu.edu

Supplementary information:  Supplementary data are available at Bioinformatics online.
A powerful and efficient set test for genetic markers that handles confounders
Authors: Listgarten Jennifer , Lippert Christoph , Kang Eun Yong , Xiang Jing , Kadie Carl M. , Heckerman David
Published: April 2013

Motivation: Approaches for testing sets of variants, such as a set of rare or common variants within a gene or pathway, for association with complex traits are important. In particular, set tests allow for aggregation of weak signal within a set, can capture interplay among variants and reduce the burden of multiple hypothesis testing. Until now, these approaches did not address confounding by family relatedness and population structure, a problem that is becoming more important as larger datasets are used to increase power.

Results: We introduce a new approach for set tests that handles confounders. Our model is based on the linear mixed model and uses two random effects—one to capture the set association signal and one to capture confounders. We also introduce a computational speedup for two random-effects models that makes this approach feasible even for extremely large cohorts. Using this model with both the likelihood ratio test and score test, we find that the former yields more power while controlling type I error. Application of our approach to richly structured Genetic Analysis Workshop 14 data demonstrates that our method successfully corrects for population structure and family relatedness, whereas application of our method to a 15 000 individual Crohn’s disease case–control cohort demonstrates that it additionally recovers genes not recoverable by univariate analysis.

Availability: A Python-based library implementing our approach is available at http://mscompbio.codeplex.com.

Contact:  jennl@microsoft.com or lippert@microsoft.com or heckerma@microsoft.com

Supplementary information:  Supplementary data are available at Bioinformatics online.
Suv4-20h2 mediates chromatin compaction and is important for cohesin recruitment to heterochromatin
Authors: Hahn Matthias , Dambacher Silvia , Dulev Stanimir , Kuznetsova Anastasia Yurievna , Eck Simon , Wörz Stefan , Sadic Dennis , Schulte Maike , Mallm Jan-Philipp , Maiser Andreas , Debs Pierre , von Melchner Harald , Leonhardt Heinrich , Schermelleh Lothar , Rohr Karl , Rippe Karsten , Storchova Zuzana , Schotta Gunnar
Published: April 2013

Cohesin plays an important role in chromatid cohesion and has additional functions in higher-order chromatin organization and in transcriptional regulation. The binding of cohesin to euchromatic regions is largely mediated by CTCF or the mediator complex. However, it is currently unknown how cohesin is recruited to pericentric heterochromatin in mammalian cells. Here we define the histone methyltransferase Suv4-20h2 as a major structural constituent of heterochromatin that mediates chromatin compaction and cohesin recruitment. Suv4-20h2 stably associates with pericentric heterochromatin through synergistic interactions with multiple heterochromatin protein 1 (HP1) molecules, resulting in compaction of heterochromatic regions.Suv4-20hmutant cells display an overall reduced chromatin compaction and an altered chromocenter organization in interphase referred to as “chromocenter scattering.” We found thatSuv4-20h-deficient cells display chromosome segregation defects during mitosis that coincide with reduced sister chromatid cohesion. Notably, cohesin subunits interact with Suv4-20h2 both in vitro and in vivo. This interaction is necessary for cohesin binding to heterochromatin, asSuv4-20hmutant cells display substantially reduced cohesin levels at pericentric heterochromatin. This defect is most prominent in G0-phase cells, where cohesin is virtually lost from heterochromatin, suggesting that Suv4-20h2 is involved in the initial loading or maintenance of cohesion subunits. In summary, our data provide the first compelling evidence that Suv4-20h2 plays essential roles in regulating nuclear architecture and ensuring proper chromosome segregation.
Numerical constraints and feedback control of double-strand breaks in mouse meiosis
Authors: Kauppi Liisa , Barchi Marco , Lange Julian , Baudat Frédéric , Jasin Maria , Keeney Scott
Published: April 2013

Different organisms display widely different numbers of the programmed double-strand breaks (DSBs) that initiate meiotic recombination (e.g., hundreds per meiocyte in mice and humans vs. dozens in nematodes), but little is known about what drives these species-specific DSB set points or the regulatory pathways that control them. Here we examine male mice with a lowered dosage of SPO11, the meiotic DSB catalyst, to gain insight into the effect of reduced DSB numbers on mammalian chromosome dynamics. An approximately twofold DSB reduction was associated with the reduced ability of homologs to synapse along their lengths, provoking prophase arrest and, ultimately, sterility. In many spermatocytes, chromosome subsets displayed a mix of synaptic failure and synapsis with both homologous and nonhomologous partners (“chromosome tangles”). The X chromosome was nearly always involved in tangles, and small autosomes were involved more often than large ones. We conclude that homolog pairing requirements dictate DSB set points during meiosis. Importantly, our results reveal that karyotype is a key factor: Smaller autosomes and heteromorphic sex chromosomes become weak links when DSBs are reduced below a critical threshold. Unexpectedly, unsynapsed chromosome segments trapped in tangles displayed an elevated density of DSB markers later in meiotic prophase. The unsynapsed portion of the X chromosome in wild-type males also showed evidence that DSB numbers increased as prophase progressed. These findings point to the existence of a feedback mechanism that links DSB number and distribution with interhomolog interactions.
Preparation, characterisation and selected functional properties of hydrolysed sodium caseinate–maltodextrin conjugate
Authors: Regan Jonathan O' , Mulvihill Daniel M
Published: April 2013

Sodium caseinate was hydrolysed to a limited, moderate or extensive degree. The hydrolysates were conjugated with maltodextrin by a Maillard‐type reaction by dry‐heat treatment at 60 °C and 79% relative humidity for 2 or 4 days. Conjugates were characterised by SDS–PAGE and gel permeation chromatography. In comparison with the hydrolysates themselves, the conjugated hydrolysates had improved solubility, particularly around the isoelectric pH of the protein. The emulsifying properties of these conjugates were assessed in oil‐in‐water (o/w) emulsions; on emulsion formation, each conjugate‐stabilised emulsion had lower mean fat globule size than the corresponding hydrolysate‐stabilised emulsion. After storage for 7 days under accelerated shelf life testing conditions, the limited and moderate hydrolysate conjugate–stabilised emulsions had improved storage stability compared with hydrolysate‐stabilised emulsions; however, further research is required to optimise the hydrolysate fraction prior to conjugation for the production of novel low molecular weight emulsifiers.
Neolithic settlement of the eastern Yemen Plateau: an exploration of locational choice and land use
Authors: Fedele Francesco G.
Published: April 2013

Knowledge of the Neolithic in the Yemeni highlands still rests on very limited sampling. The available data for the eastern belt of the plateau derive from the Italian Mission's explorations of 1981–84, still largely unpublished, and a survey conducted in Wādī Khamar in 1987 and 1990. Focusing on settlement problems, this paper attempts an examination of locational choice from a review at both the regional and local scales, including information obtained from a study of the late A. de Maigret's notebooks. Regionally, specific settlement patterns appear to emerge and significant links to mid‐Holocene environmental ‘enclaves’ can be advanced, permitting speculation on land use. On the local scale, site composition and variation are reviewed on the basis of the three excavated sites (Jabal Quṭrān, An‐Najid al‐Abyaḍ 7 and Wādī aṯ‐Ṯayyilah 3). Understanding the specificity of Neolithic settlement in the uplands is still a distant goal, and the considerable unknowns involved are outlined.
Back to Fasad… and the PPNB controversy. Questioning a Levantine origin for Arabian Early Holocene projectile points technology
Authors: Charpentier Vincent , Crassard Rémy
Published: April 2013

For decades, so‐called Fasad points have been discovered in Oman and the UAE. These lithic projectile points have been until now fossiles directeurs (or defining artefacts) for Early Holocene human occupation prior to the development of the Arabian Neolithic. It appears that many different types of points are described in the literature as Fasad points, but the actual variability of the archaeological discoveries leads to the necessity for reassessment and clarification of the very definition of this type of artefact. We propose here a new definition of the Fasad points with the creation of sub‐types. We also discuss the trend of using this lithic type as a marker for the diffusion of PPNB technology towards the south‐east from the Mediterranean Levantine Neolithic core area.
The Neolithic in Arabia: a view from the south
Authors: McCorriston Joy
Published: April 2013

Maurizio Tosi alerted prehistorians to the significant evidence that Arabia followed its own path and with Serge Cleuziou has made a compelling argument about the distinctive social structure of Arabian complexity. After a decade of research and analyses based in Wadi Sana, Hadramawt, the RASA Project can offer a hypothetical scheme of the earliest social developments in highland southern Arabia.

Domesticated animals came first;

They were probably adopted or used by hunters still prizing wild game;

Dedicated pastoralism emerged in situ, accompanied by an increase in population density and the definition of strategic territories;

In southern Arabia, a distinct Neolithic culture of sacrifice began as social‐boundary maintenance to secure resources;

Social strategies changed, with the introduction of more complex and broadly negotiated axes of power;

Agriculture was introduced late, and the first deliberate cultivation may not have involved domesticated plants. Whatever was cultivated was used to maintain Neolithic populations committed to territories;

This Neolithic culture set the foundation for subsequent Arabian cultures.
Environmental variables associated with the distribution and occupancy of habitat specialist tadpoles in naturally acidic, oligotrophic waterbodies
Authors: Simpkins Clay Alan , Shuker Jonathan D. , Lollback Gregory W. , Castley J. Guy , Hero Jean‐Marc
Published: April 2013

Environmental factors play an integral role, either directly or indirectly, in structuring faunal assemblages. Water chemistry, predation, hydroperiod and competition influence tadpole assemblages within waterbodies. We surveyed aquatic predators, habitat refugia, water height and water chemistry variables (pH, salinity and turbidity) at 37 waterbodies over an intensive 22‐day field survey to determine which environmental factors influence the relative abundance and occupancy of two habitat specialist anuran tadpole species in naturally acidic, oligotrophic waterbodies within eastern Australian wallum communities. The majority of tadpoles found were of Litoria olongburensis (wallum sedge frog) and Crinia tinnula (wallum froglet) species, both habitat specialists that are associated with wallum waterbodies and listed as Vulnerable under the IUCN Red List. Tadpoles of two other species (Litoria fallax (eastern sedge frog), and Litoria cooloolensis (cooloola sedge frog)) were recorded from two waterbodies. Tadpoles of Litoria gracilenta (graceful treefrog) were recorded from one waterbody. Relative abundance and occupancy of L. olongburensis tadpoles were associated with pH and water depth. Additionally, L. olongburensis tadpole relative abundance was negatively associated with turbidity. Waterbody occupancy by C. tinnula tadpoles was negatively associated with predatory fish and water depth and positively associated with turbidity. Variables associated with relative abundance of C. tinnula tadpoles were inconclusive and further survey work is required to identify these environmental factors. Our results show that the ecology of specialist and non‐specialist tadpole species associated with ‘unique’ (e.g. wallum) waterbodies is complex and species specific, with specialist species likely dominating unique habitats.
Density, nest site characteristics and breeding rates of the osprey (Pandion haliaetus) in the southern limit of its range in the Western Palearctic (Boa Vista, Cape Verde Islands)
Authors: Siverio Manuel , López‐Suárez Pedro , Siverio Felipe , Rodríguez Beneharo , Varo‐Cruz Nuria , López‐Jurado Luis F.
Published: April 2013

Between 2004 and 2007, we studied density, habitat features and breeding parameters of the osprey (Pandion haliaetus) population in Boa Vista Island (Cape Verde). A total of 79 nest structures were identified, 37 of which were occupied for at least 1 year during the study period. The osprey population ranged between 14 and 18 pairs, and the mean density and distance between neighbouring occupied nests were 2.58 pairs per 100 km2 and 3089 m, respectively. Occupied nests were found to be significantly further from the coastline and roads than unoccupied nests, but the distances from villages were similar. The majority (81.1%) of the 37 occupied nests were easily accessible to humans. Mean clutch size was 2.59, average productivity was 0.76 young/active nest, and breeding success was 58.8% [Correction added on 13 May 2013, after first online publication: the average productivity was changed from 0.72 to 0.76]. Density in Boa Vista was higher than that in other sedentary island populations in the Western Palearctic, whereas the productivity was the lowest of this region. Clutch size did not vary among Western Palearctic populations, but the differences observed in productivity were likely influenced by local factors that in Boa Vista are attributed to nest depredation by the brown‐necked raven (Corvus ruficollis) and to direct human persecution.
Tracheal repair in children: reduction of mortality with advent of slide tracheoplasty
Authors: Yong Matthew S. , d'Udekem Yves , Robertson Colin F. , Butt Warwick , Brizard Christian P. , Konstantinov Igor E.
Published: April 2013

Background

Severe tracheal stenosis is a rare life‐threatening condition that often requires early surgical intervention. The management of this anomaly has been associated with significant mortality and morbidity. We describe our experience with repair of this condition.

Methods

From 1986 to 2011, 20 patients underwent repair of tracheal stenosis at the Royal Children's Hospital (median age 4.9 months) and were retrospectively reviewed.

Results

Tracheal repair techniques used were as follows: patch tracheoplasty (n = 8; 40%, 8 out of 20), slide tracheoplasty (n = 7; 35%, 7 out of 20), end‐to‐end anastomosis (n = 5; 25%, 5 out of 20). Six patients (30%, 6 out of 20) had coexisting congenital intracardiac anomalies. There were 12 pulmonary artery sling (60%, 12 out of 20) patients. Overall operative mortality was 15% (n = 3; 3 out of 20). Operative mortality was 20% (n = 2; 2 out of 10) from 1986 to 2001 and decreased to 10% (n = 1; 1 out of 10) from 2002 to 2011. All early deaths occurred in patients who had undergone patch tracheoplasty. Since 2004, there were no operative deaths. Seven patients (35%, 7 out of 20) required tracheal reintervention postoperatively. There were three late deaths (17.6%, 3 out of 17) at 8, 9 and 22 months after surgery. At last follow‐up (mean 5.3 ± 6.6 years; range 1 month to 18 years), all 14 survivors remained asymptomatic.

Conclusions

Repair of tracheal stenosis in children has been associated with high morbidity and mortality. Since the introduction of slide tracheoplasty, a multidisciplinary team approach and abandonment of patch tracheoplasty, the mortality has been reduced. Survival beyond 2 years after surgery is associated with an excellent outcome.
Surgical safety checklists: a review
Authors: Tang Reuben , Ranmuthugala Geetha , Cunningham Frances
Published: April 2013

Background

Surgical checklists are designed to improve patient outcomes following surgery. While such checklists have been widely implemented worldwide, few studies examine surgical checklists within an Australian context. For this purpose, we have performed a literature review using data from OECD member nations to determine the effectiveness of surgical checklists in improving patient outcomes and factors that contribute to their successful implementation.

Method

The databases, Pubmed, Medline, EMBASE, Cochrane and CINAHL were searched using the keywords (‘surgical’ AND ‘checklist’) and ( (surgical) AND checklist) AND ( (implementation) OR (utilization) OR (usage) ). Studies were limited to those written in the English language, peer‐reviewed, published between January 2000 and December 2012, and including an abstract.

Results

Our search yielded 2242 papers, of which 72 papers were identified for their potential relevance and selected for full text review. Of these, nine papers met the inclusion criteria and were reviewed in detail. Evidence that supports the use of surgical checklists in countries with a large number of protocols already in place is limited. Adequate checklist implementation plays a central role in checklist effectiveness, which in turn is dependent on multiple factors.

Conclusion

Although evidence from OECD member countries is non‐conclusive, it does suggest that surgical checklists, when effectively implemented, have the potential to be effective at reducing complication and mortality rates following surgery. Within an Australian context, more studies are needed to fully establish the potential effectiveness of surgical checklists and to monitor checklist use compliance in order to ensure greater patient safety.
Perioperative management of anticoagulation in elective surgery
Authors: McKenzie Jo‐Lyn , Douglas Genevieve , Bazargan Ali
Published: April 2013

Surgeons commonly need to treat patients receiving anticoagulant and anti‐platelet therapy. This requires risk assessment and management to balance minimization of bleeding complications and avoidance of further ischaemic or thrombotic events. This review considers the evidence available to guide management of patients on anti‐platelet and anticoagulant therapy, including some of the new classes of anti‐platelets and anticoagulants which clinicians may be less familiar with.
Evolution of diagnostic criteria for gestational diabetes mellitus
Authors: Houshmand Azadeh , Jensen Dorte Møller , Mathiesen Elisabeth R. , Damm Peter
Published: April 2013

The establishment of universal diagnostic guidelines for gestational diabetes mellitus has been a long time coming. The lack of consensus and uniformity in procedures for diagnosing this disease has been a problem ever since its existence was recognized. The USA, European countries, and Australia have each developed their own guidelines through the years, all based either on the maternal risk of subsequent diabetes, on arbitrary statistics, or on studies conducted on non‐pregnant women. None of these guidelines have been based on risk for perinatal complications. Recently, the Hyperglycemia and Adverse Pregnancy Outcomes study demonstrated that maternal hyperglycemia is associated with perinatal risk in a linear way with no obvious threshold. The International Association of Diabetes and Pregnancy Study Group has translated these results into clinical practice by proposing new diagnostic criteria for gestational diabetes mellitus, based for the first time on perinatal outcome.
Characteristics of Wenchuan earthquake victims who remained in a government‐supported transitional community
Authors: Ma Ning , Ma Hong , He Hua , Yu Xin , Caine Eric D.
Published: April 2013

Introduction

The Chinese government and provincial authorities built a large number of temporary communities to shelter survivors after the May 2008 Wenchuan earthquake. Most residents left within a few months but others remained. This study describes the characteristics and psychological status of those victims who remained in a government‐supported transitional community 12 months post‐earthquake compared to residents who departed prior to that time.

Methods

Two groups of survivors of Wenchuan earthquake who resided in a transitional community were enrolled: 86 in December 2008 and 151 in February 2009. We assessed their mental distress, symptoms of depression and post‐traumatic stress disorder and suicide risk. Forty‐three and 46 members of the two groups, respectively, had departed the transitional community at 1 year post‐earthquake.

Results

In both groups, most of the survivors who remained in the community 1 year post‐earthquake were older, female, with a lower education level and more serious personal losses. They had scored higher on self‐report measures reflecting distressing symptoms and impairment as compared with their departed neighbors, and had a higher prevalence of depression and suicide risk at the time of enrollment.

Discussion

Survivors who come to live in a transitional community following a disaster are heterogeneous. Remaining survivors were apparently more vulnerable and had a lower capacity to seek work and return to a more self‐sustaining life outside the transitional community. Such vulnerable survivors require distinctive strategies for making a successful return to independent living.
Peripheral selectivity of the novel cannabinoid receptor antagonist TM38837 in healthy subjects
Authors: Klumpers Linda E. , Fridberg Marianne , de Kam Marieke L. , Little Paul B. , Jensen Niels Ole , Kleinloog Hendrik D. , Elling Christian E. , van Gerven Joop M. A.
Published: April 2013

Aim

Cannabinoid receptor type 1 (CB1) antagonists show central side effects, whereas beneficial effects are most likely peripherally mediated. In this study, the peripherally selective CB1 antagonist TM38837 was studied in humans.

Methods

This was a double‐blind, randomized, placebo‐controlled, crossover study. On occasions 1–4, 24 healthy subjects received 5 × 4 mg THC with TM38837 100 mg, 500 mg or placebo, or placebos only. During occasion 5, subjects received placebo TM38837 + THC with rimonabant 60 mg or placebo in parallel groups. Blood collections and pharmacodynamic (PD) effects were assessed frequently. Pharmacokinetics (PK) and PD were quantified using population PK−PD modelling.

Results

The TM38837 plasma concentration profile was relatively flat compared with rimonabant. TM38837 showed an estimated terminal half‐life of 771 h. THC induced effects on VAS feeling high, body sway and heart rate were partly antagonized by rimonabant 60 mg [−26.70% [90% confidence interval (CI) −40.9, −12.6%]; −7.10%, (90%CI −18.1, 5.3%); −7.30%, (90% CI −11.5%, −3.0%) respectively] and TM38837 500 mg [−22.10% (90% CI −34.9, −9.4%); −12.20% (90% CI −21.6%, −1.7%); −8.90% (90% CI −12.8%, −5.1%) respectively]. TM38837 100 mg had no measurable feeling high or body sway effects and limited heart rate effects.

Conclusions

Rimonabant showed larger effects than TM38837, but the heart rate effects were similar. TM38837 100 mg had no impact on CNS effects, suggesting that this dose does not penetrate the brain. This TM38837 dose is predicted to be at least equipotent to rimonabant with regard to metabolic disorders in rodent models. These results provide support for further development of TM38837 as a peripherally selective CB1 antagonist for indications such as metabolic disorders, with a reduced propensity for psychiatric side effects.