Self-amplified photo-induced gap quenching in a correlated electron material.

Capturing the dynamic electronic band structure of a correlated material presents a powerful capability for uncovering the complex couplings between the electronic and structural degrees of freedom. When combined with ultrafast laser excitation, new phases of matter can result, since far-from-equilibrium excited states are instantaneously populated. Here, we elucidate a general relation between ultrafast non-equilibrium electron dynamics and the size of the characteristic energy gap in a correlated electron material. We show that carrier multiplication via impact ionization can be one of the most important processes in a gapped material, and that the speed of carrier multiplication critically depends on the size of the energy gap. In the case of the charge-density wave material 1T-TiSe2, our data indicate that carrier multiplication and gap dynamics mutually amplify each other, which explains-on a microscopic level-the extremely fast response of this material to ultrafast optical excitation

Differential impact of two risk communications on antipsychotic prescribing to people with dementia in Scotland: segmented regression time series analysis 2001-2011

The two risk communications were associated with reductions in antipsychotic use, in ways which were compatible with marked differences in their content and dissemination. Further research is needed to ensure that the content and dissemination of regulatory risk communications is optimal, and to track their impact on intended and unintended outcomes. Although rates are falling, antipsychotic prescribing in dementia in Scotland remains unacceptably hig

Microscopic observation of magnon bound states and their dynamics

More than eighty years ago, H. Bethe pointed out the existence of bound states of elementary spin waves in one-dimensional quantum magnets. To date, identifying signatures of such magnon bound states has remained a subject of intense theoretical research while their detection has proved challenging for experiments. Ultracold atoms offer an ideal setting to reveal such bound states by tracking the spin dynamics after a local quantum quench with single-spin and single-site resolution. Here we report on the direct observation of two-magnon bound states using in-situ correlation measurements in a one-dimensional Heisenberg spin chain realized with ultracold bosonic atoms in an optical lattice. We observe the quantum walk of free and bound magnon states through time-resolved measurements of the two spin impurities. The increased effective mass of the compound magnon state results in slower spin dynamics as compared to single magnon excitations. In our measurements, we also determine the decay time of bound magnons, which is most likely limited by scattering on thermal fluctuations in the system. Our results open a new pathway for studying fundamental properties of quantum magnets and, more generally, properties of interacting impurities in quantum many-body systems.Comment: 8 pages, 7 figure

Granulocyte-Colony Stimulating Factor (G-CSF) Improves Motor Recovery in the Rat Impactor Model for Spinal Cord Injury

Granulocyte-colony stimulating factor (G-CSF) improves outcome after experimental SCI by counteracting apoptosis, and enhancing connectivity in the injured spinal cord. Previously we have employed the mouse hemisection SCI model and studied motor function after subcutaneous or transgenic delivery of the protein. To further broaden confidence in animal efficacy data we sought to determine efficacy in a different model and a different species. Here we investigated the effects of G-CSF in Wistar rats using the New York University Impactor. In this model, corroborating our previous data, rats treated subcutaneously with G-CSF over 2 weeks show significant improvement of motor function

Alkali activation of vitreous calcium aluminosilicate derived from glass fiber waste

The properties and microstructure of alkali-activated (AA) vitreous calcium aluminosilicate (VCAS) are presented in this paper. VCAS is manufactured from a by-product of the glass fiber industry and has been activated using NaOH and KOH solutions. The microstructure and mechanical properties of AA VCAS pastes and mortars are reported. The results show that depending on the type and concentration of hydroxide solution used, mortar samples with compressive strengths up to 77 MPa can be formed after curing for three days at 65 °C. The research demonstrates the potential of VCAS to produce AA cements and the importance of alkali type and concentration in optimizing properties and microstructure.Mitsuuchi Tashima, M.; Soriano Martinez, L.; Borrachero Rosado, MV.; Monzó Balbuena, JM.; Cheeseman, CR.; Paya Bernabeu, JJ. (2012). Alkali activation of vitreous calcium aluminosilicate derived from glass fiber waste. Journal of Sustainable Cement-Based Materials. 1(3):83-93. doi:10.1080/21650373.2012.742610S839313Mahasenan N, Smith S, Humphreys K. The cement industry and global climate change: current and potential future cement industry CO2emissions. Greenhouse Gas Control Technologies – 6th International Conference. Oxford: Pergamon; 2003. p. 995–1000.Schneider, M., Romer, M., Tschudin, M., & Bolio, H. (2011). Sustainable cement production—present and future. Cement and Concrete Research, 41(7), 642-650. doi:10.1016/j.cemconres.2011.03.019WBCSD – World Business Council for Sustainable Development. Cement industry energy and CO2performance – Getting numbers right. Edited by WBCSD, Geneva-Switzerland (ISBN 978-3-940388-48-3). 2009.Shi, C., Jiménez, A. F., & Palomo, A. (2011). New cements for the 21st century: The pursuit of an alternative to Portland cement. Cement and Concrete Research, 41(7), 750-763. doi:10.1016/j.cemconres.2011.03.016Duxson, P., Fernández-Jiménez, A., Provis, J. L., Lukey, G. C., Palomo, A., & van Deventer, J. S. J. (2006). Geopolymer technology: the current state of the art. Journal of Materials Science, 42(9), 2917-2933. doi:10.1007/s10853-006-0637-zFernández-Jiménez, A., Palomo, A., & Criado, M. (2005). Microstructure development of alkali-activated fly ash cement: a descriptive model. Cement and Concrete Research, 35(6), 1204-1209. doi:10.1016/j.cemconres.2004.08.021Hossain, A. B., Shirazi, S. A., Persun, J., & Neithalath, N. (2008). Properties of Concrete Containing Vitreous Calcium Aluminosilicate Pozzolan. Transportation Research Record: Journal of the Transportation Research Board, 2070(1), 32-38. doi:10.3141/2070-05Neithalath, N., Persun, J., & Hossain, A. (2009). Hydration in high-performance cementitious systems containing vitreous calcium aluminosilicate or silica fume. Cement and Concrete Research, 39(6), 473-481. doi:10.1016/j.cemconres.2009.03.006Tashima MM, Soriano L, Borrachero MV, Monzó J, Payá J. Effect of curing time on the microstructure and mechanical strength development of alkali activated nbinders based on vitreous calcium aluminosilicate (VCAS). Bull. Mater. Sci. in press.Hemmings RT, Nelson RD, Graves PL, Cornelius BJ. White pozzolan composition and blended cements containing same. Patent US6776838. 2004.Provis, J. L., Lukey, G. C., & van Deventer, J. S. J. (2005). Do Geopolymers Actually Contain Nanocrystalline Zeolites? A Reexamination of Existing Results. Chemistry of Materials, 17(12), 3075-3085. doi:10.1021/cm050230iCriado, M., Fernández-Jiménez, A., de la Torre, A. G., Aranda, M. A. G., & Palomo, A. (2007). An XRD study of the effect of the SiO2/Na2O ratio on the alkali activation of fly ash. Cement and Concrete Research, 37(5), 671-679. doi:10.1016/j.cemconres.2007.01.013Rees, C. A., Provis, J. L., Lukey, G. C., & van Deventer, J. S. J. (2007). In Situ ATR-FTIR Study of the Early Stages of Fly Ash Geopolymer Gel Formation. Langmuir, 23(17), 9076-9082. doi:10.1021/la701185gLee, W. K. W., & van Deventer, J. S. J. (2003). Use of Infrared Spectroscopy to Study Geopolymerization of Heterogeneous Amorphous Aluminosilicates. Langmuir, 19(21), 8726-8734. doi:10.1021/la026127eGarcía-Lodeiro, I., Fernández-Jiménez, A., Blanco, M. T., & Palomo, A. (2007). FTIR study of the sol–gel synthesis of cementitious gels: C–S–H and N–A–S–H. Journal of Sol-Gel Science and Technology, 45(1), 63-72. doi:10.1007/s10971-007-1643-6Barbosa VFF. Sintese e caracterização de polissialatos (Synthesis and characterization of polysialates) [PhD thesis] (in Portuguese). Instituto Militar de Engenharia. Rio de Janeiro - Brazil. 190 p. 1999.Bernal, S. A., Rodríguez, E. D., Mejía de Gutiérrez, R., Gordillo, M., & Provis, J. L. (2011). Mechanical and thermal characterisation of geopolymers based on silicate-activated metakaolin/slag blends. Journal of Materials Science, 46(16), 5477-5486. doi:10.1007/s10853-011-5490-zBoccaccini, A. R., Bücker, M., Bossert, J., & Marszalek, K. (1997). Glass matrix composites from coal flyash and waste glass. Waste Management, 17(1), 39-45. doi:10.1016/s0956-053x(97)00035-4Kourti, I., Rani, D. A., Deegan, D., Boccaccini, A. R., & Cheeseman, C. R. (2010). Production of geopolymers using glass produced from DC plasma treatment of air pollution control (APC) residues. Journal of Hazardous Materials, 176(1-3), 704-709. doi:10.1016/j.jhazmat.2009.11.089Lampris, C., Lupo, R., & Cheeseman, C. R. (2009). Geopolymerisation of silt generated from construction and demolition waste washing plants. Waste Management, 29(1), 368-373. doi:10.1016/j.wasman.2008.04.007Wu, H.-C., & Sun, P. (2007). New building materials from fly ash-based lightweight inorganic polymer. Construction and Building Materials, 21(1), 211-217. doi:10.1016/j.conbuildmat.2005.06.052Kourti, I., Amutha Rani, D., Boccaccini, A. R., & Cheeseman, C. R. (2011). Geopolymers from DC Plasma–Treated Air Pollution Control Residues, Metakaolin, and Granulated Blast Furnace Slag. Journal of Materials in Civil Engineering, 23(6), 735-740. doi:10.1061/(asce)mt.1943-5533.000017

Neural correlates of enhanced visual short-term memory for angry faces: An fMRI study

Copyright: © 2008 Jackson et al.Background: Fluid and effective social communication requires that both face identity and emotional expression information are encoded and maintained in visual short-term memory (VSTM) to enable a coherent, ongoing picture of the world and its players. This appears to be of particular evolutionary importance when confronted with potentially threatening displays of emotion - previous research has shown better VSTM for angry versus happy or neutral face identities.Methodology/Principal Findings: Using functional magnetic resonance imaging, here we investigated the neural correlates of this angry face benefit in VSTM. Participants were shown between one and four to-be-remembered angry, happy, or neutral faces, and after a short retention delay they stated whether a single probe face had been present or not in the previous display. All faces in any one display expressed the same emotion, and the task required memory for face identity. We find enhanced VSTM for angry face identities and describe the right hemisphere brain network underpinning this effect, which involves the globus pallidus, superior temporal sulcus, and frontal lobe. Increased activity in the globus pallidus was significantly correlated with the angry benefit in VSTM. Areas modulated by emotion were distinct from those modulated by memory load.Conclusions/Significance: Our results provide evidence for a key role of the basal ganglia as an interface between emotion and cognition, supported by a frontal, temporal, and occipital network.The authors were supported by a Wellcome Trust grant (grant number 077185/Z/05/Z) and by BBSRC (UK) grant BBS/B/16178

Research of the origin of a particular Tunisian group using a physical marker and Alu insertion polymorphisms

The aim of this study was to show how, in some particular circumstances, a physical marker can be used along with molecular markers in the research of an ancient people movement. A set of five Alu insertions was analysed in 42 subjects from a particular Tunisian group (El Hamma) that has, unlike most of the Tunisian population, a very dark skin, similar to that of sub-Saharans, and in 114 Tunisian subjects (Gabes sample) from the same governorate, but outside the group. Our results showed that the El Hamma group is genetically midway between sub-Saharan populations and North Africans, whereas the Gabes sample is clustered among North Africans. In addition, The A25 Alu insertion, considered characteristic to sub-Saharan Africans, was present in the El Hamma group at a relatively high frequency. This frequency was similar to that found in sub-Saharans from Nigeria, but significantly different from those found in the Gabes sample and in other North African populations. Our molecular results, consistent with the skin color status, suggest a sub-Saharan origin of this particular Tunisian group

Population Genetics of Franciscana Dolphins (Pontoporia blainvillei): Introducing a New Population from the Southern Edge of Their Distribution

Due to anthropogenic factors, the franciscana dolphin, Pontoporia blainvillei, is the most threatened small cetacean on the Atlantic coast of South America. Four Franciscana Management Areas have been proposed: Espiritu Santo to Rio de Janeiro (FMA I), São Paulo to Santa Catarina (FMA II), Rio Grande do Sul to Uruguay (FMA III), and Argentina (FMA IV). Further genetic studies distinguished additional populations within these FMAs. We analyzed the population structure, phylogeography, and demographic history in the southernmost portion of the species range. From the analysis of mitochondrial DNA control region sequences, 5 novel haplotypes were found, totalizing 60 haplotypes for the entire distribution range. The haplotype network did not show an apparent phylogeographical signal for the southern FMAs. Two populations were identified: Monte Hermoso (MH) and Necochea (NC)+Claromecó (CL)+Río Negro (RN). The low levels of genetic variability, the relative constant size over time, and the low levels of gene flow may indicate that MH has been colonized by a few maternal lineages and became isolated from geographically close populations. The apparent increase in NC+CL+RN size would be consistent with the higher genetic variability found, since genetic diversity is generally higher in older and expanding populations. Additionally, RN may have experienced a recent split from CL and NC; current high levels of gene flow may be occurring between the latter ones. FMA IV would comprise four franciscana dolphin populations: Samborombón West+Samborombón South, Cabo San Antonio+Buenos Aires East, NC+CL+Buenos Aires Southwest+RN and MH. Results achieved in this study need to be taken into account in order to ensure the long-term survival of the species.Fil: Gariboldi, María Constanza. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; ArgentinaFil: Tunez, Juan Ignacio. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Luján; ArgentinaFil: Dejean, Cristina Beatriz. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina. Universidad de Buenos Aires. Facultad de Filosofía y Letras. Instituto de Ciencias Antropológicas. Sección Antropología Biológica; ArgentinaFil: Failla, Mauricio. Fundación Cethus; ArgentinaFil: Vitullo, Alfredo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; ArgentinaFil: Negri, Maria Fernanda. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; ArgentinaFil: Cappozzo, Humberto Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Maimónides. Área de Investigaciones Biomédicas y Biotecnológicas. Centro de Estudios Biomédicos, Biotecnológicos, Ambientales y de Diagnóstico; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Museo Argentino de Ciencias Naturales ; Argentin

Response to ‘Re: Kakkos et al. Efficacy and Safety of the New Oral Anticoagulants Dabigatran, Rivaroxaban, Apixaban, and Edoxaban in the Treatment and Secondary Prevention of Venous Thromboembolism: A Systematic Review and Meta-analysis of Phase III Trials’

We estimated and compared the risk of clinically identified acquired drug resistance under immediate initiation [the currently recommended antiretroviral therapy (ART) initiation strategy], initiation with CD4 cell count less than 500 cells/μl and initiation with CD4 cell count less than 350 cells/μl. Cohort study based on routinely collected data from the HIV-CAUSAL collaboration. For each individual, baseline was the earliest time when all eligibility criteria (ART-naive, AIDS free, and others) were met after 1999. Acquired drug resistance was defined using the Stanford classification as resistance to any antiretroviral drug that was clinically identified at least 6 months after ART initiation. We used the parametric g-formula to adjust for time-varying (CD4 cell count, HIV RNA, AIDS, ART regimen, and drug resistance testing) and baseline (calendar period, mode of acquisition, sex, age, geographical origin, ethnicity and cohort) characteristics. In 50 981 eligible individuals, 10% had CD4 cell count more than 500 cells/μl at baseline, and 63% initiated ART during follow-up. Of 2672 tests for acquired drug resistance, 794 found resistance. The estimated 7-year risk (95% confidence interval) of acquired drug resistance was 3.2% (2.8,3.5) for immediate initiation, 3.1% (2.7,3.3) for initiation with CD4 cell count less than 500 cells/μl, and 2.8% (2.5,3.0) for initiation with CD4 cell count less than 350 cells/μl. In analyses restricted to individuals with baseline in 2005-2015, the corresponding estimates were 1.9% (1.8, 2.5), 1.9% (1.7, 2.4), and 1.8% (1.7, 2.2). Our findings suggest that the risk of acquired drug resistance is very low, especially in recent calendar periods, and that immediate ART initiation only slightly increases the risk. It is unlikely that drug resistance will jeopardize the proven benefits of immediate ART initiation

Mortality after infection with methicillin-resistant Staphylococcus aureus (MRSA) diagnosed in the community

<p>Abstract</p> <p>Background</p> <p>Outbreak reports suggest that community-acquired methicillin-resistant <it>Staphylococcus aureus </it>(MRSA) infections can be life-threatening. We conducted a population based cohort study to assess the magnitude of mortality associated with MRSA infections diagnosed in the community.</p> <p>Methods</p> <p>We used the United Kingdom's General Practice Research Database (GPRD) to form a cohort of all patients with MRSA diagnosed in the community from 2001 through 2004 and up to ten patients without an MRSA diagnosis. The latter were frequency-matched with the MRSA patients on age, GPRD practice and diagnosis date. All patients were older than 18 years, had no hospitalization in the 2 years prior to cohort entry and medical history information of at least 2 years prior to cohort entry. The cohort was followed up for 1 year and all deaths and hospitalizations were identified. Hazard ratios of all-cause mortality were estimated using the Cox proportional hazards model adjusted for patient characteristics.</p> <p>Results</p> <p>The cohort included 1439 patients diagnosed with MRSA and 14,090 patients with no MRSA diagnosis. Mean age at cohort entry was 70 years in both groups, while co-morbid conditions were more prevalent in the patients with MRSA. Within 1 year, 21.8% of MRSA patients died as compared with 5.0% of non-MRSA patients. The risk of death was increased in patients diagnosed with MRSA in the community (adjusted hazard ratio 4.1; 95% confidence interval: 3.5–4.7).</p> <p>Conclusion</p> <p>MRSA infections diagnosed in the community are associated with significant mortality in the year after diagnosis.</p