bluuebunny/crossref_metadata_2025 huggingface dataset:
Chromatin dynamics during cellular differentiation in the female reproductive lineage of flowering plants
Authors: Baroux Célia , Autran Daphné
Published: May 2015

Sexual reproduction in flowering plants offers a number of remarkable aspects to developmental biologists. First, the spore mother cells – precursors of the plant reproductive lineage – are specified late in development, as opposed to precocious germline isolation during embryogenesis in most animals. Second, unlike in most animals where meiosis directly produces gametes, plant meiosis entails the differentiation of a multicellular, haploid gametophyte, within which gametic as well as non‐gametic accessory cells are formed. These observations raise the question of the factors inducing and modus operandi of cell fate transitions that originate in floral tissues and gametophytes, respectively. Cell fate transitions in the reproductive lineage imply cellular reprogramming operating at the physiological, cytological and transcriptome level, but also at the chromatin level. A number of observations point to large‐scale chromatin reorganization events associated with cellular differentiation of the female spore mother cells and of the female gametes. These include a reorganization of the heterochromatin compartment, the genome‐wide alteration of the histone modification landscape, and the remodeling of nucleosome composition. The dynamic expression of DNA methyltransferases and actors of small RNA pathways also suggest additional, global epigenetic alterations that remain to be characterized. Are these events a cause or a consequence of cellular differentiation, and how do they contribute to cell fate transition? Does chromatin dynamics induce competence for immediate cellular functions (meiosis, fertilization), or does it also contribute long‐term effects in cellular identity and developmental competence of the reproductive lineage? This review attempts to review these fascinating questions.
Complex interactions among residues within pore region determine the K+ dependence of a KAT1‐type potassium channel AmKAT1
Authors: Yang Guangzhe , Sentenac Hervé , Véry Anne‐Aliénor , Su Yanhua
Published: May 2015

KAT1‐type channels mediate K+ influx into guard cells that enables stomatal opening. In this study, a KAT1‐type channel AmKAT1 was cloned from the xerophyte Ammopiptanthus mongolicus. In contrast to most KAT1‐type channels, its activation is strongly dependent on external K+ concentration, so it can be used as a model to explore the mechanism for the K+‐dependent gating of KAT1‐type channels. Domain swapping between AmKAT1 and KAT1 reveals that the S5–pore–S6 region controls the K+ dependence of AmKAT1, and residue substitutions show that multiple residues within the S5–Pore linker and Pore are involved in its K+‐dependent gating. Importantly, complex interactions occur among these residues, and it is these interactions that determine its K+ dependence. Finally, we analyzed the potential mechanism for the K+ dependence of AmKAT1, which could originate from the requirement of K+ occupancy in the selectivity filter to maintain its conductive conformation. These results provide new insights into the molecular basis of the K+‐dependent gating of KAT1‐type channels.
Modeling and Characterization of a Photovoltaic Array Based on Actual Performance Using Cascade-Forward Back Propagation Artificial Neural Network
Authors: Ameen Ammar Mohammed , Pasupuleti Jagadeesh , Khatib Tamer , Elmenreich Wilfried , Kazem Hussein A.
Published: May 2015

This paper proposes a novel prediction model for photovoltaic (PV) system output current. The proposed model is based on cascade-forward back propagation artificial neural network (CFNN) with two inputs and one output. The inputs are solar radiation and ambient temperature, while the output is output current. Two years of experimental data for a 1.4 kWp PV system are utilized in this research. The monitored performance is recorded every 2 s in order to consider the uncertainty of the system’s output current. A comparison between the proposed model and other empirical and statistical models is done in this paper as well. Moreover, the ability of the proposed model to predict performance with high uncertainty rate is validated. Three statistical values are used to evaluate the accuracy of the proposed model, namely, mean absolute percentage error (MAPE), mean bias error (MBE), and root mean square error (RMSE). These values are used to measure the deviation between the actual and the predicted data in order to judge the accuracy of the proposed model. A simple estimation of the deviation between the measured value and the predicted value with respect to the measured value is first given by MAPE. After that, the average deviation of the predicted values from measured data is estimated by MBE in order to indicate the amount of the overestimation/underestimation in the predicted values. Third, the ability of predicting future records is validated by RMSE, which represents the variation of the predicted data around the measured data. Eventually, the percentage of MBE and RMSE is calculated with respect to the average value of the output current so as to present better understating of model’s accuracy. The results show that the MAPE, MBE, and RMSE of the proposed model are 7.08%, −0.21 A (−4.98%), and 0.315 A (7.5%), respectively. In addition to that, the proposed model exceeds the other models in terms of prediction accuracy.
Thermal Behavior in a Transient State of a Case of Hollow Block: Transfer Function Coefficients
Authors: Ait-Taleb T. , Abdelbaki A. , Zrikem Z.
Published: May 2015

The aim of this work is to determine the empirical transfer function coefficients (TFCs) for the case of a hollow tile with two air cells deep in the vertical direction. We start with the prediction of combined heat transfer by conduction, natural convection, and radiation by using a detailed numerical simulation when the system is submitted to the realistic time varying temperatures. Then, the results of the simulation (the time-varying heat fluxes at the hollow tile surfaces) are used to obtain empirical TFCs by using an identification method. The dynamic responses of the hollow tile that are predicted using both the TFCs and the simulation program are compared for thermal excitations that differ from those used to derive the coefficients. The results show a good harmony between the two procedures’ predictions. In addition, other different comparisons in terms of the overall thermal conductance coefficients are presented and discussed.
Effective Community-Based Physical Activity Interventions for Older Adults Living in Rural and Regional Areas: A Systematic Review
Authors: Moore Melissa , Warburton Jeni , O’Halloran Paul D. , Shields Nora ,   Kingsley
Published: May 2015

The purpose of this systematic review was to assess the characteristics and effectiveness of community-based interventions designed to increase physical activity participation in older adults (aged 65 years or more) living in rural or regional areas. Relevant peer-reviewed literature was obtained, using four primary electronic search engines, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement. The initial search identified 4,690 articles. After removal of duplicates and excluded articles, seven articles were included in the review. Few consistencies existed between intervention types, duration, outcome measures, and follow-up. Results provide some evidence to support the effectiveness of community-based interventions that include low- to moderate-intensity exercise to increase physical activity, physical function, and psychological state. However, without more rigorous studies it is difficult to identify the most critical characteristics of community-based interventions for older adults in rural and regional settings.
Validity of a Self-Report Recall Tool for Estimating Sedentary Behavior in Adults
Authors: Gomersall Sjaan R. , Pavey Toby G. , Clark Bronwyn K. , Jasman Adib , Brown Wendy J.
Published: May 2015

Background:

Sedentary behavior is continuing to emerge as an important target for health promotion. The purpose of this study was to determine the validity of a self-report use of time recall tool, the Multimedia Activity Recall for Children and Adults (MARCA) in estimating time spent sitting/lying, compared with a device-based measure.

Methods:

Fifty-eight participants (48% female, [mean ± standard deviation] 28 ± 7.4 years of age, 23.9 ± 3.05 kg/m2) wore an activPAL device for 24-h and the following day completed the MARCA. Pearson correlation coefficients (r) were used to analyze convergent validity of the adult MARCA compared with activPAL estimates of total sitting/lying time. Agreement was examined using Bland-Altman plots.

Results:

According to activPAL estimates, participants spent 10.4 hr/day [standard deviation (SD) = 2.06] sitting or lying down while awake. The correlation between MARCA and activPAL estimates of total sit/lie time was r = .77 (95% confidence interval = 0.64–0.86; P < .001). Bland-Altman analyses revealed a mean bias of +0.59 hr/day with moderately wide limits of agreement (–2.35 hr to +3.53 hr/day).

Conclusions:

This study found a moderate to strong agreement between the adult MARCA and the activPAL, suggesting that the MARCA is an appropriate tool for the measurement of time spent sitting or lying down in an adult population.
The shape and structure of cometary nuclei as a result of low-velocity accretion
Authors: Jutzi M. , Asphaug E.
Published: May 2015

Collisions give comets their shape

The shape and structure of comets are relicts of collision processes from long ago. Despite recent and ongoing spacecraft missions that offer direct measurements of cometary nuclei, it is difficult to test what is important in comet shaping. Jutzi and Asphaug ran ∼100 three-dimensional collision simulations across a wide range of target and impactor masses and trajectories. Slow and less violent collisions produced the layering and bi-lobed shapes of actual comets.

Science
, this issue p.
1355
Epigenetic silencing by the HUSH complex mediates position-effect variegation in human cells
Authors: Tchasovnikarova Iva A. , Timms Richard T. , Matheson Nicholas J. , Wals Kim , Antrobus Robin , Göttgens Berthold , Dougan Gordon , Dawson Mark A. , Lehner Paul J.
Published: May 2015

Keeping quiet one gene at a time

Chromosomal DNA comes in two flavors—euchromatin, which contains most of the expressed genes, and heterochromatin, which usually remains quiet. But what keeps genes within heterochromatin silent? Tchasovnikarova
et al.
examined the basis for this type of silencing in mammalian cells (see the Perspective by Brummelkamp). They identified a complex of proteins in human cells they called HUSH that kept particular parts of the genome silent by changing associated histone methylation marks.

Science
, this issue p.
1481
, see also p.
1433
Draft Genome Sequence of the Archiascomycetous Yeast
Saitoella complicata
Authors: Yamauchi Kenta , Kondo Shinji , Hamamoto Makiko , Takahashi Yurika , Ogura Yoshitoshi , Hayashi Tetsuya , Nishida Hiromi
Published: May 2015

The draft genome sequence of the archiasomycetous yeast
Saitoella complicata
was determined. The assembly of newly and previously sequenced data sets resulted in 104 contigs (total of 14.1 Mbp;
N
50
, 239 kbp). On the newly assembled genome, a total of 6,933 protein-coding sequences (7,119 transcripts, including alternative splicing forms) were identified.
Draft Genome Sequence of
Vibrio
sp. Strain Vb278, an Antagonistic Bacterium Isolated from the Marine Sponge
Sarcotragus spinosulus
Authors: Gonçalves Ana C. S. , Franco Telma , Califano Gianmaria , Dowd Scot E. , Pohnert Georg , Costa Rodrigo
Published: May 2015

We report here the draft genome sequence of
Vibrio
sp. Vb278, a biofilm-producing strain isolated from the marine sponge
Sarcotragus spinosulus
, showing
in vitro
antibacterial activity. The annotated genome displays a range of symbiotic factors and the potential for the biosynthesis of several biologically active natural products.
Draft Genome Sequence of Enterohemorrhagic Escherichia coli O157 NCCP15739, Isolated in the Republic of Korea
Authors: Kwon Taesoo , Cho Seung-Hak
Published: May 2015

Enterohemorrhagic
Escherichia coli
(EHEC) is the main cause of the recent outbreaks of diarrhea, hemolytic-uremic syndrome (HUS), and hemorrhagic colitis worldwide. Herein, we present the draft genome sequence of the NCCP15739 isolate from a patient in the Republic of Korea.
Complete Genome Sequence of Microcystis aeruginosa NIES-2549, a Bloom-Forming Cyanobacterium from Lake Kasumigaura, Japan
Authors: Yamaguchi Haruyo , Suzuki Shigekatsu , Tanabe Yuuhiko , Osana Yasunori , Shimura Yohei , Ishida Ken-ichiro , Kawachi Masanobu
Published: May 2015

Microcystis aeruginosa
NIES-2549 is a freshwater bloom-forming cyanobacterium isolated from Lake Kasumigaura, Japan. We report the complete 4.29-Mbp genome sequence of NIES-2549 and its annotation and discuss the genetic diversity of
M. aeruginosa
strains. This is the third genome sequence of
M. aeruginosa
isolated from Lake Kasumigaura.
Complete Genome Sequence of Uropathogenic Escherichia coli Strain CI5
Authors: Mehershahi Kurosh S. , Abraham Soman N. , Chen Swaine L.
Published: May 2015

Escherichia coli
represents the primary etiological agent responsible for urinary tract infections, one of the most common infections in humans. We report here the complete genome sequence of uropathogenic
Escherichia coli
strain CI5, a clinical pyelonephritis isolate used for studying pathogenesis.
Complete Genome Sequence of Mycoplasma synoviae Strain WVU 1853
T
Authors: May Meghan A. , Kutish Gerald F. , Barbet Anthony F. , Michaels Dina L. , Brown Daniel R.
Published: May 2015

A hybrid sequence assembly of the complete
Mycoplasma synoviae
type strain WVU 1853
T
genome was compared to that of strain MS53. The findings support prior conclusions about
M. synoviae
, based on the genome of that otherwise uncharacterized field strain, and provide the first evidence of epigenetic modifications in
M. synoviae
.
Want to Inspire Science Students to Consider a Research Career? Host a Scientist in Your Classroom
Authors: Baynham Patricia J.
Published: May 2015

Most biology students have limited exposure to research since this is not a public activity and the pace of science does not lend itself to television dramatization. In contrast, medicine is the subject of numerous TV shows, and students’ experience visiting doctors may lead them to think they want to become physicians. One effective way to encourage these students to consider a research career is to invite engaging scientists to speak about their career paths and lives during class. Students are most likely to be influenced by people they consider to be like themselves. While this method is well-suited to a lecture format where the scientist can address a larger audience, the laboratory would also be appropriate.
AML transformation after autologous stem cell transplant for multiple myeloma
Authors: Gupta Sanjeev Kumar , Chandramohan Jagan , Kumar Lalit
Published: May 2015

A 59-year-old male patient was diagnosed as multiple myeloma in 2005 and received chemotherapy consisting of thalidomide, cyclophosphamide, and dexamethasone. The patient subsequently received high-dose melphalan followed by autologous stem cell transplantation and maintenance therapy with thalidomide. During the follow-up, the patient developed fever and cytopenias in 2012. The work up revealed 55% blasts in the marrow with myeloid phenotype leading to a diagnosis of acute myeloma leukaemia (AML). The karyotype was normal (46,XY) on conventional cytogenetics. The therapy was initiated, however, the patient expired within 1 month of diagnosis. The treatment related factors like alkylating agents are usually taken as the responsible agents for therapy-related AML, however, recent studies have proposed a multifactorial pathogenesis of leukaemic transformation in multiple myeloma.
Diagnosis and treatment of chlamydia and gonorrhoea in general practice in England 2000–2011: a population-based study using data from the UK Clinical Practice Research Datalink
Authors: Wetten Sally , Mohammed Hamish , Yung Mandy , Mercer Catherine H , Cassell Jackie A , Hughes Gwenda
Published: May 2015

Objectives

To determine the relative contribution of general practices (GPs) to the diagnosis of chlamydia and gonorrhoea in England and whether treatment complied with national guidelines.

Design

Analysis of longitudinal electronic health records in the Clinical Practice Research Datalink (CPRD) and national sexually transmitted infection (STI) surveillance databases, England, 2000–2011.

Setting

GPs, and community and specialist STI services.

Participants

Patients diagnosed with chlamydia (n=1 386 169) and gonorrhoea (n=232 720) at CPRD GPs, and community and specialist STI Services from 2000–2011.

Main outcome measures

Numbers and rates of chlamydia and gonorrhoea diagnoses; percentages of patients diagnosed by GPs relative to other services; percentage of GP patients treated and antimicrobials used; percentage of GP patients referred.

Results

The diagnosis rate (95% CI) per 100 000 population of chlamydia in GP increased from 22.8 (22.4–23.2) in 2000 to 29.3 (28.8–29.7) in 2011 (p<0.001), while the proportion treated increased from 59.5% to 78.4% (p=0.001). Over 90% were prescribed a recommended antimicrobial. Over the same period, the diagnosis rate (95% CI) per 100 000 population of gonorrhoea in GP ranged between 3.2 (3–3.3) and 2.4 (2.2–2.5; p=0.607), and the proportion treated ranged between 32.7% and 53.6% (p=0.262). Despite being discontinued as a recommended therapy for gonorrhoea in 2005, ciprofloxacin accounted for 42% of prescriptions in 2007 and 20% in 2011. Over the study period, GPs diagnosed between 9% and 16% of chlamydia cases and between 6% and 9% of gonorrhoea cases in England.

Conclusions

GP makes an important contribution to the diagnosis and treatment of bacterial STIs in England. While most patients diagnosed with chlamydia were managed appropriately, many of those treated for gonorrhoea received antimicrobials no longer recommended for use. Given the global threat of antimicrobial resistance, GPs should remain abreast of national treatment guidelines and alert to treatment failure in their patients.
Comparing the impact of personal and parental risk factors, and parental lifespan on all-cause mortality and cardiovascular disease: findings from the Midspan Family cohort study
Authors: Hart Carole , McCartney Gerry , Gruer Laurence , Watt Graham
Published: May 2015

Background

We aimed to identify which personal and parental factors best explained all-cause mortality and cardiovascular disease (CVD).

Methods

In 1996, data were collected on 2338 adult offspring of the participants in the 1972–1976 Renfrew and Paisley prospective cohort study. Recorded risk factors were assigned to 5 groups: mid-life biological and behavioural (BB), mid-life socioeconomic, parental BB, early-life socioeconomic and parental lifespan. Participants were followed up for mortality and hospital admissions to the end of 2011. Cox proportional hazards models were used to analyse how well each group explained all-cause mortality or CVD. Akaike's Information Criterion (AIC), a measure of goodness-of-fit, identified the most important groups.

Results

For all-cause mortality (1997 participants with complete data, 111 deaths), decreases in AIC from the null model (adjusting for age and sex) to models including mid-life BB, mid-life socioeconomic, parental BB, early-life socioeconomic and parental lifespan were 55.8, 21.6, 10.3, 7.3 and 5.9, respectively. For the CVD models (1736 participants, 276 with CVD), decreases were 37.8, 3.7, 6.7, 17.3 and 0.4. Mid-life BB factors were the most important for both all-cause mortality and CVD; mid-life socioeconomic factors were important for all-cause mortality, and early-life socioeconomic factors were important for CVD. Parental lifespan was the weakest factor.

Conclusions

As mid-life BB risk factors best explained all-cause mortality and CVD, continued action to reduce these is warranted. Targeting adverse socioeconomic factors in mid-life and early life may contribute to reducing all-cause mortality and CVD risk, respectively.
Online learning for all
Authors: Doherty Simon
Published: May 2015

Last year, Simon Doherty, president of the North of Ireland Veterinary Association and the BVA's NI Branch, completed a number of MOOCs (massive open online courses) having read about them in Vet Record Careers; here, he describes his experiences.
Excavating the history of ancient veterinary practices
Authors: Binois Annelise
Published: May 2015

People have lived alongside animals for many centuries, and it can be assumed that they also treated them when they were sick. There are some texts that describe early veterinary care, but details are lacking and medical instruments are hard to come by in archaeological sites. However, as Annelise Binois explains, archaeological findings can provide a lot more information than might be thought, and can start to give a glimpse of the vast history of veterinary medicine.
Virulence and antimicrobial susceptibility of clinical and environmental strains of Aeromonas spp. from northeastern Brazil
Authors: Castelo-Branco Débora de Souza Collares Maia , Guedes Glaucia Morgana de Melo , Brilhante Raimunda Sâmia Nogueira , Rocha Marcos Fábio Gadelha , Sidrim José Júlio Costa , Moreira José Luciano Bezerra , Cordeiro Rossana de Aguiar , Sales Jamille Alencar , Riello Giovanna Barbosa , Alencar Lucas Pereira de , Paiva Manoel de Araújo Neto , Vasconcelos David Caldas , Bezerra de Menezes Isis Sousa , Ponte Yago Brito de , Sampaio Célia Maria de Souza , Monteiro André Jalles , Bandeira Tereza de Jesus Pinheiro Gomes
Published: May 2015

The aims of the present study were to isolate and identify clinical and environmental strains of Aeromonas spp. by means of biochemical tests and the automated method VITEK 2 and to investigate the presence of the virulence genes cytotoxic enterotoxin (act), hemolysin (asa-1), and type III secretion system (ascV), and also the in vitro antimicrobial susceptibility of the strains. From the clinical isolates, 19 Aeromonas hydrophila, 3 Aeromonas veronii bv. sobria, and 1 Aeromonas caviae were identified, while from the environmental strains, 11 A. hydrophila, 22 A. veronii bv. sobria, 1 A. veronii bv. veronii, and 1 A. caviae were recovered. The gene act was detected in 69.5% of clinical isolates, asa-1 in 8.6%, and ascV in 34.7%. In the environmental strains, the detection rates were 51.4%, 45.7%, and 54.2% for the genes act, asa-1, and ascV, respectively. Resistance to amoxicillin–clavulanate and piperacillin–tazobactam was observed in 15 and 3 clinical strains, respectively, and resistance to ceftazidime, meropenem, imipenem, ciprofloxacin, and trimethoprim–sulfamethoxazole was observed in 1 strain for each drug. Resistance to amoxicillin–clavulanate and piperacillin–tazobactam was detected in 17 and 1 environmental strain, respectively. Higher resistance percentages were observed in clinical strains, but environmental strains also showed this phenomenon and presented a higher detection rate of virulence genes. Thus, it is important to monitor the antimicrobial susceptibility and pathogenic potential of the environmental isolates.
Topological gauge fixing II: A homotopy formulation
Authors: Gallot L. , Pilon E. , Thuillier F.
Published: May 2015

We revisit the implementation of the metric-independent Fock–Schwinger gauge in the Abelian Chern–Simons field theory defined in ℝ3 by means of a homotopy condition. This leads to the Lagrangian [Formula: see text] in terms of curvatures F and of the Poincaré homotopy operator h. The corresponding field theory provides the same link invariants as the Abelian Chern–Simons theory. Incidentally the part of the gauge field propagator which yields the link invariants of the Chern–Simons theory in the Fock–Schwinger gauge is recovered without any computation.
Direct writing of porous tissue scaffolds based on Vaseline-doped hydroxyapatite inks
Authors: Li Ya-Yun , Li Long-Tu , Li Bo
Published: May 2015

A novel type of 40 vol.% hydroxyapatite ( HAp ), Ca 10( PO 4)6( OH )2, suspension doped with Vaseline was developed, and porous three-dimensional (3D) scaffolds were fabricated by using a direct ink writing (DIW) method. The preparation of the HAp inks and the principles of the DIW technique were investigated. The microporosity of the scaffold wall increased after introducing the Vaseline, whereas macroporosity can be produced by varying the DIW technique. The micromorphology test results show that the samples sintered at 1150°C for 2 h formed ceramics with a set amount of pores, which benefit cell growth by providing more locations for cells to attach and proliferate. Under a microscope, the proliferations of human liver carcinoma cell line ( HepG2 ) cells can be observed on the 3D HAp scaffolds. The DIW method has the advantages of a rapid process, ease of design and high precision control, potentially inspiring the design and application of biomaterials and scaffolds.
Many-body origin of supersolidity
Authors: Yu Yongle
Published: May 2015

We present a microscopic many-body argument for supersolidity. We suggest that super-solidity can be realized in 20 Ne .
Hierarchical Scheduling Optimization Scheme in Hybrid Cloud Computing Environments
Authors: Li Chunlin , Li LaYuan
Published: May 2015

The paper proposes hierarchical scheduling optimization scheme in hybrid cloud. Our proposed hierarchical scheduling takes advantage of the interaction of cloud users, private cloud and public cloud. For high level optimization in hybrid cloud, the objective of public cloud provider optimization is to maximize the revenue of providing virtual machines (VMs) and minimize the energy cost. The private cloud users' applications give the unique optimal payment to public cloud providers under deadline and cost constraint to maximize the satisfaction of private cloud user applications. The objective of low-level scheduling optimization is to minimize the cost and execution time of private cloud application. From the simulation results, the revenue, execution success ratio and resource utilization of our proposed hierarchical scheduling algorithm are better than other related works.
A GLUING LEMMA FOR ITERATED FUNCTION SYSTEMS
Authors: KAMAE TETURO , LUO JUN , TAN BO
Published: May 2015

We obtain a special version of gluing lemma related to the theory of iterated function systems (IFS). As an application, we verify that a family of concrete n-dimensional self-affine tiles {Tn, r : 0 ≤ r < 3, n ≥ 3} are homeomorphic with the unit cube [0,1]n. The tiles Tn, r are "nontrivial" in the sense that each of them is neither a self-affine polytope nor the product of an interval with an (n - 1)-dimensional self-affine tile.
Return to Rodinia? Moderate to high palaeolatitude of the São Francisco/Congo craton at 920 Ma
Authors: Evans D. A. D. , Trindade R. I. F. , Catelani E. L. , D'Agrella-Filho M. S. , Heaman L. M. , Oliveira E. P. , Söderlund U. , Ernst R. E. , Smirnov A. V. , Salminen J. M.
Published: May 2015

Moderate to high palaeolatitudes recorded in mafic dykes, exposed along the coast of Bahia, Brazil, are partly responsible for some interpretations that the São Francisco/Congo craton was separate from the low-latitude Rodinia supercontinent at about 1050 Ma. We report new palaeomagnetic data that replicate the previous results. However, we obtain substantially younger U–Pb baddeleyite ages from five dykes previously thought to be 1.02–1.01 Ga according to the
40
Ar/
39
Ar method. Specifically, the so-called ‘A-normal’ remanence direction from Salvador is dated at 924.2±3.8 Ma, within error of the age for the ‘C’ remanence direction at 921.5±4.3 Ma. An ‘A-normal’ dyke at Ilhéus is dated at 926.1±4.6 Ma, and two ‘A-normal’ dykes at Olivença have indistinguishable ages with best estimate of emplacement at 918.2±6.7 Ma. We attribute the palaeomagnetic variance of the ‘A-normal’ and ‘C’ directions to lack of averaging of geomagnetic palaeosecular variation in some regions. Our results render previous
40
Ar/
39
Ar ages from the dykes suspect, leaving late Mesoproterozoic palaeolatitudes of the São Francisco/Congo craton unconstrained. The combined ‘A-normal’ palaeomagnetic pole from coastal Bahia places the São Francisco/Congo craton in moderate to high palaeolatitudes at
c.
920 Ma, allowing various possible positions of that block within Rodinia.
Palaeomagnetism and U–Pb geochronology of
c.
1570 Ma intrusives from Åland archipelago, SW Finland – implications for Nuna
Authors: Salminen Johanna M. , Klein Robert , Mertanen Satu , Pesonen Lauri J. , Fröjdö Sören , Mänttäri Irmeli , Eklund Olav
Published: May 2015

We report new palaeomagnetic and isotope age data of Early Mesoproterozoic (i.e. Subjotnian) intrusions from the Åland archipelago, SW Finland. The palaeomagnetic results reveal dual-polarity magnetizations with a pronounced reversal asymmetry occurring in dykes. We explain the asymmetry by an unremoved secondary component, which is affecting more N-polarity dykes. Other explanations, such as the age difference of magnetization between normal and reversed polarity dykes, are discussed. The primary nature of magnetization in dykes for both normal (N) and reversed (R) groups is verified by positive baked contact tests. A dyke showing reversed polarity from Korsö is dated 1575.9±3.0 Ma (U–Pb) in this study. This and previous U–Pb data tighten the magmatic activity in Åland to 1580–1570 Ma. We combined new palaeomagnetic data with those from earlier studies to provide a new key-palaeomagnetic pole for Baltica. Our data positions Baltica on equatorial latitudes, supporting the NENA (North Europe–North America) connection between Baltica and Laurentia at 1.59–1.58 Ga. Palaeomagnetic data support that NENA was valid at 1.75, 1.58, 1.46, and 1.26 Ga, forming the core of Mesoproterozoic Nuna (a.k.a. Columbia) supercontinent.
Tectonostratigraphic evolution of the
c.
780–730 Ma Beck Spring Dolomite: Basin Formation in the core of Rodinia
Authors: Smith Emily F. , MacDonald Francis A. , Crowley James L. , Hodgin Eben B. , Schrag Daniel P.
Published: May 2015

The Beck Spring Dolomite is a mixed carbonate–siliciclastic succession exposed in Death Valley, California, that was deposited between 780 and 717 Ma. Along with its bounding units, the Horse Thief Springs Formation below and unit KP1 of the Kingston Peak Formation above, the Beck Spring Dolomite were deposited in one of the ChUMP (Chuar–Uinta Mountains–Pahrump) basins with subsidence commonly attributed to the nascent rifting of Rodinia. These pre-Sturtian successions preserve eukaryotic microfossil assemblages, diverse microbialites, and large carbon isotope anomalies directly below Sturtian-age glacial deposits. Here we present new geological mapping, measured stratigraphic sections, carbon isotope chemostratigraphy and detrital zircon geochronology from the Beck Spring Dolomite and its bounding units. The carbon isotope excursion at the top of the Beck Spring Dolomite has previously been attributed to meteoric diagenesis associated with karst breccias, but here we demonstrate that these breccias are instead mass flow deposits that formed during deposition of the Kingston Peak Formation and that the carbon isotope excursion is not only reproducible throughout the basin, but is associated with transgression rather than regression and exposure. In addition, we refine local correlations and discuss the use of chemostratigraphic curves from these units for regional and global correlations. The Beck Spring Dolomite was deposited during the second of three distinct basin-forming events recorded in the Pahrump Group with basin inversion occurring between each event. The presence of syn-sedimentary faults, the character of the lateral facies change and detrital zircon provenance analyses indicate that the Beck Spring Dolomite fringed a coeval palaeo-high to the south in a tectonically active basin. Detrital zircon age distributions in the Beck Spring Dolomite show sharp probability peaks at
c.
1200, 1400 and 1800 Ma, consistent with local sources to the SW in the Mojave block rather than transcontinental rivers. The
c.
1800 Ma probability peak is less prominent in the KP1 samples. In addition, KP1 also records slump folding and is overlain by an unconformity. We suggest that these features are consistent with the emergence of a local fault to the NE. Deposition of the Beck Spring Dolomite and bounding units do not record evidence of incipient rifting of the western margin of Laurentia but instead reflect a distinct and separate tectonothermal event.

Supplementary material:

Carbon (δ
13
C) and oxygen (δ
18
O) isotopic measurements, detrital zircon laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) data, detrital zircon sample information and data from reference materials used for LA-ICPMS analyses are available at
http://www.geolsoc.org.uk/SUP18823
.
Chemoprevention in gastrointestinal physiology and disease. Anti-inflammatory approaches for colorectal cancer chemoprevention
Authors: Fajardo Alexandra M. , Piazza Gary A.
Published: May 2015

Colorectal cancer (CRC) is one of the most common human malignancies and a leading cause of cancer-related deaths in developed countries. Identifying effective preventive strategies aimed at inhibiting the development and progression of CRC is critical for reducing the incidence and mortality of this malignancy. The prevention of carcinogenesis by anti-inflammatory agents including nonsteroidal anti-inflammatory drugs (NSAIDs), selective cyclooxygenase-2 (COX-2) inhibitors, and natural products is an area of considerable interest and research. Numerous anti-inflammatory agents have been identified as potential CRC chemopreventive agents but vary in their mechanism of action. This review will discuss the molecular mechanisms being studied for the CRC chemopreventive activity of NSAIDs (i.e., aspirin, sulindac, and ibuprofen), COX-2 inhibitors (i.e., celecoxib), natural products (i.e., curcumin, resveratrol, EGCG, genistein, and baicalein), and metformin. A deeper understanding of how these anti-inflammatory agents inhibit CRC will provide insight into the development of potentially safer and more effective chemopreventive drugs.
Oxidative capacity and glycogen content increase more in arm than leg muscle in sedentary women after intense training
Authors: Nordsborg Nikolai B. , Connolly Luke , Weihe Pál , Iuliano Enzo , Krustrup Peter , Saltin Bengt , Mohr Magni
Published: May 2015

The hypothesis that the adaptive capacity is higher in human upper- than lower-body skeletal muscle was tested. Furthermore, the hypothesis that more pronounced adaptations in upper-body musculature can be achieved by “low-volume high-intensity” compared with “high-volume low-intensity” exercise training was evaluated. A group of sedentary premenopausal women aged 45 ± 6 yr (± SD) with expected high adaptive potential in both upper- and lower-extremity muscle groups participated. After random allocation to high-intensity swimming (HIS, n = 21), moderate-intensity swimming (MOS, n = 21), soccer (SOC, n = 21) or a nontraining control group (CON, n = 20), the training groups completed three workouts per week for 15 wk. Resting muscle biopsies were obtained from the vastus lateralis muscle and deltoideus muscle before and after the intervention. After the training intervention, a larger ( P < 0.05) increase existed in deltoideus muscle of the HIS group compared with vastus lateralis muscle of the SOC group for citrate synthase maximal activity (95 ± 89 vs. 27 ± 34%), citrate synthase protein expression (100 ± 29 vs. 31 ± 44%), 3-hydroxyacyl-CoA dehydrogenase maximal activity (35 ± 43 vs. 3 ± 25%), muscle glycogen content (63 ± 76 vs. 20 ± 51%), and expression of mitochondrial complex II, III, and IV. Additionally, HIS caused higher ( P < 0.05) increases than MOS in deltoideus muscle citrate synthase maximal activity, citrate synthase protein expression, and muscle glycogen content. In conclusion, the deltoideus muscle has a higher adaptive potential than the vastus lateralis muscle in sedentary women, and “high-intensity low-volume” training is a more efficient regime than “low-intensity high-volume” training for increasing the aerobic capacity of the deltoideus muscle.
Depth-dependent variations in Achilles tendon deformations with age are associated with reduced plantarflexor performance during walking
Authors: Franz Jason R. , Thelen Darryl G.
Published: May 2015

The anatomical arrangement of the Achilles tendon (AT), with distinct fascicle bundles arising from the gastrocnemius and soleus muscles, may facilitate relatively independent behavior of the triceps surae muscles. A reduced capacity for sliding between adjacent tendon fascicles with age may couple gastrocnemius and soleus muscle behavior, thereby potentially contributing to diminished plantarflexor performance commonly observed in old adults. Nine healthy young (mean age, 23.9 yr) and eight healthy old (69.9 yr) adults walked at three speeds (0.75, 1.00, and 1.25 m/s) on a force-sensing treadmill. We coupled dynamic ultrasound imaging of the free AT with motion capture and inverse dynamic analyses to compute, in part: 1) depth-dependent variations in AT tissue displacements and elongations and 2) net ankle joint kinetics during push-off. The difference in displacements between superficial and deep AT regions, and in their corresponding elongations, did not differ between old and young adults at the slower two walking speeds ( P > 0.61). However, old adults walked with 41% smaller depth-dependent variations in free AT displacements and elongations at 1.25 m/s ( P = 0.02). These more uniform tendon deformations in old adults most strongly correlated with reduced peak ankle moment ( R2= 0.40), but also significantly correlated with reduced peak power generation ( R2= 0.15) and positive ankle work during push-off ( R2= 0.19) ( P > 0.01). Our findings: 1) demonstrate a potential role for nonuniform AT deformations in governing gastrocnemius and soleus muscle-tendon function and 2) allude to altered tendon behavior that may contribute to the age-related reduction in plantarflexor performance during walking.
Pneumothorax effects on pulmonary acoustic transmission
Authors: Mansy Hansen A. , Balk Robert A. , Warren William H. , Royston Thomas J. , Dai Zoujun , Peng Ying , Sandler Richard H.
Published: May 2015

Pneumothorax (PTX) is an abnormal accumulation of air between the lung and the chest wall. It is a relatively common and potentially life-threatening condition encountered in patients who are critically ill or have experienced trauma. Auscultatory signs of PTX include decreased breath sounds during the physical examination. The objective of this exploratory study was to investigate the changes in sound transmission in the thorax due to PTX in humans. Nineteen human subjects who underwent video-assisted thoracic surgery, during which lung collapse is a normal part of the surgery, participated in the study. After subjects were intubated and mechanically ventilated, sounds were introduced into their airways via an endotracheal tube. Sounds were then measured over the chest surface before and after lung collapse. PTX caused small changes in acoustic transmission for frequencies below 400 Hz. A larger decrease in sound transmission was observed from 400 to 600 Hz, possibly due to the stronger acoustic transmission blocking of the pleural air. At frequencies above 1 kHz, the sound waves became weaker and so did their changes with PTX. The study elucidated some of the possible mechanisms of sound propagation changes with PTX. Sound transmission measurement was able to distinguish between baseline and PTX states in this small patient group. Future studies are needed to evaluate this technique in a wider population.
l-Citrulline supplementation improves O2 uptake kinetics and high-intensity exercise performance in humans
Authors: Bailey Stephen J. , Blackwell Jamie R. , Lord Terrence , Vanhatalo Anni , Winyard Paul G. , Jones Andrew M.
Published: May 2015

The purpose of this study was to compare the effects of l-citrulline (Cit) and l-arginine (Arg) supplementation on nitric oxide (NO) biomarkers, pulmonary O2 uptake (V̇o2) kinetics, and exercise performance. In a randomized, placebo (Pla)-controlled, crossover study, 10 healthy adult men completed moderate- and severe-intensity cycling exercise on days 6 and 7 of a 7-day supplementation period with Pla, Arg (6 g/day), and Cit (6 g/day). Compared with Pla, plasma Arg concentration was increased by a similar magnitude with Arg and Cit supplementation, but plasma Cit concentration was only increased ( P < 0.001) with Cit supplementation. Plasma nitrite (NO2−) concentration was increased with Arg supplementation ( P < 0.05) and tended to increase with Cit supplementation ( P = 0.08) compared with Pla (83 ± 25, 106 ± 41, and 100 ± 38 nM with Pla, Arg, and Cit, respectively); however, mean arterial blood pressure was only lower ( P < 0.05) after Cit supplementation. The steady-state V̇o2 amplitude during moderate-intensity cycle exercise was not significantly different between supplements, but Cit lowered the V̇o2 mean response time (59 ± 8 and 53 ± 5 s with Pla and Cit, respectively, P < 0.05) during severe-intensity exercise, improved tolerance to severe-intensity exercise (589 ± 101 and 661 ± 107 s with Pla and Cit, respectively), and increased the total amount of work completed in the exercise performance test (123 ± 18 and 125 ± 19 kJ with Pla and Cit, respectively, P < 0.05). These variables were not altered by Arg supplementation ( P > 0.05). In conclusion, these results suggest that short-term Cit, but not Arg, supplementation can improve blood pressure, V̇o2 kinetics, and exercise performance in healthy adults.
miR-663 Suppresses Oncogenic Function of CXCR4 in Glioblastoma
Authors: Shi Yu , Chen Cong , Yu Shi-Zhu , Liu Qing , Rao Jun , Zhang Hua-Rong , Xiao Hua-Liang , Fu Ti-Wei , Long Hua , He Zhi-Cheng , Zhou Kai , Yao Xiao-Hong , Cui You-Hong , Zhang Xia , Ping Yi-Fang , Bian Xiu-Wu
Published: May 2015

Purpose: To identify the miRNA regulators of C–X–C motif chemokine receptor 4 (CXCR4) and the underlying mechanism as well as the therapeutic and prognostic values in human glioblastoma (GBM).

Experimental Design: miRNA profile analyses and bioinformatics predictions were used to identify the mediators of CXCR4, which were confirmed by luciferase reporter assay, Western blot assay and immunohistochemistry. The effects of miR-663 on CXCR4-mediated GBM malignancy were investigated by gain-of-function experiments. Orthotopic xenografts derived from constitutive or induced miR-663–expressing GBM cells were used to determine the antitumor effects of miR-663 and CXCR4-specific antagonist AMD3100. Bivariate correlation analyses were used to examine the correlation of miR-663 and CXCR4 levels in glioma. The prognostic values of miR-663 and CXCR4 were examined in 281 cases of astrocytic glioma from our hospital and 476 cases of GBM from The Cancer Genome Atlas database using the multivariate Cox regression analysis and Kaplan–Meier analysis.

Results: miR-663 negatively regulated CXCR4 expression by targeting its coding sequence in GBM and compromised the proliferative and invasive capacities of GBM cells induced by CXCR4 overexpression. Constitutive or induced miR-663 overexpression combined with CXCR4 antagonist AMD3100 suppressed orthotopic GBM growth and prolonged tumor-bearing mice survival. Clinically, miR-663 and CXCR4 were inversely correlated in GBM and composed a valuable biomarker set in predicting the outcomes of GBM patients.

Conclusions: miR-663 negatively regulated CXCR4 to inhibit its oncogenic effect. Combination of miR-663 and CXCR4 can serve as a valuable prognostic biomarker set as well as molecular targets for therapeutic intervention of GBM. Clin Cancer Res; 21(17); 4004–13. ©2015 AACR.
Two Novel Mutations in the Serpina7 Gene Are Associated with Complete Deficiency of Thyroxine-Binding Globulin
Authors: Moeller Lars C. , Appiagyei-Dankah Yaw , Köhler Birgit , Biebermann Heike , Janssen Onno E. , Führer Dagmar
Published: May 2015

Background: Thyroxine-binding globulin (TBG) is the main transport protein for T4 in blood. Until now, 22 mutations leading to complete TBG deficiency (TBG-CD) have been reported. Objective: We report two mutations associated with TBG-CD found in patients from Andrews, S.C., USA (TBG-CD-Andrews), and Berlin, Germany (TBG-CD-Berlin). Methods: Automated chemiluminescence immunoassays were used for the determination of TSH, free and total T4 and T3 (fT4, TT4, TT3) and TBG. Direct DNA sequencing was used to identify the TBG mutations in the propositi. Results: TBG-CD-Andrews was found in a 1-month-old boy who was euthyroid with normal TSH and fT4, but reduced TT4, indicating TBG deficiency. TBG was not detectable, confirming TBG-CD. No mutation in the coding region and the promoter of the TBG gene was found, but a single nucleotide substitution in intron 1 disrupts the donor splice site of exon 0 (IVS1+2T>C). Another mutation was found in an 11-year-old boy. He was also euthyroid with normal fT4 and TSH. However, TT4 and TT3 were low, suggesting TBG-CD. Sequencing revealed a 79-nucleotide deletion, ranging from intron 3 into exon 3. Conclusion: We report two novel mutations of the TBG gene associated with TBG-CD. Whereas most TBG-CDs are caused by small deletions, in TBG-CD-Andrews the disruption of a donor splice site was detected, whilst in TBG-CD-Berlin the largest deletion in the Serpina7 gene to date was found.
High-Resolution Melting Is a Sensitive, Cost-Effective, Time-Saving Technique for BRAF V600E Detection in Thyroid FNAB Washing Liquid: A Prospective Cohort Study
Authors: Marino Marco , Monzani Maria Laura , Brigante Giulia , Cioni Katia , Madeo Bruno , Santi Daniele , Maiorana Antonino , Bettelli Stefania , Moriondo Valeria , Pignatti Elisa , Bonacini Lara , Carani Cesare , Rochira Vincenzo , Simoni Manuela
Published: May 2015

Objective: The diagnostic accuracy of thyroid fine needle aspiration biopsy (FNAB) can be improved by the combination of cytological and molecular analysis. In this study, washing liquids of FNAB (wFNAB) were tested for the BRAF V600E mutation, using the sensitive and cost-effective technique called high-resolution melting (HRM). The aim was to demonstrate the feasibility of BRAF analysis in wFNAB and its diagnostic utility, combined with cytology. Design: Prospective cohort study. Methods: 481 patients, corresponding to 648 FNAB samples, were subjected to both cytological (on cells smeared onto a glass slide) and molecular analysis (on fluids obtained washing the FNAB needle with 1 ml of saline) of the same aspiration. BRAF V600E analysis was performed by HRM after methodological validation for application to wFNAB (technique sensitivity: 5.4%). Results: The cytological results of the FNAB were: 136 (21%) nondiagnostic (THY1); 415 (64%) benign (THY2); 80 (12.4%) indeterminate (THY3); 9 (1.4%) suspicious for malignancy (THY4); 8 (1.2%) diagnostic of malignancy (THY5). The BRAF V600E mutation was found in 5 THY2, 2 THY3, 6 THY4 and 6 THY5 samples. Papillary carcinoma diagnosis was histologically confirmed in all BRAF+ thyroidectomized patients. BRAF combined with cytology improved the diagnostic value compared to cytology alone in a subgroup of 74 operated patients. Conclusions: HRM was demonstrated to be a feasible method for BRAF analysis in wFNAB. Thanks to its sensitivity and cost-effectiveness, it might be routinely used on a large scale in clinical practice. In perspective, standby wFNAB samples could be analyzed a posteriori in case of indeterminate cytology and/or suspicious findings on ultrasound.