Composite fermions close to the one-half filling of the lowest Landau level revisited

By strictly adhering to the microscopic theory of composite fermions for the Landau-level filling fractions nu_e = p/(2 p + 1), we reproduce, with remarkable accuracy, the surface-acoustic-wave (SAW)-based experimental results by Willett and co-workers concerning two-dimensional electron systems with nu_e close to 1/2. Our results imply that the electron band mass m_b, as distinct from the composite fermion mass m_*, must undergo a substantial increase under the conditions corresponding to nu_e approximately equal to 1/2. In view of the relatively low aerial electronic densities n_e to which the underlying SAW experiments correspond, our finding conforms with the experimental results by Shashkin et al. [Phys. Rev. B 66, 073303 (2002)], concerning two-dimensional electrons in silicon, that signal sharp increase in m_b for n_e decreasing below approximately 2 x 10^{11} cm^{-2}. We further establish that a finite mean-free path l_0 is essential for the observed linearity of the longitudinal conductivity sigma_{xx}(q) as deduced from the SAW velocity shifts.Comment: 5 pages, 2 postscript figure

Study of the effect of dust concentration on the perception of community respiratory system disorders in Bandung Regency

Ambient air pollution is one of the problems that have an impact on public health globally. Dust (PM10 and PM2.5) is one that has a major contribution to health. The concentration of dust will affect public health, especially short-term respiratory system disorders. This research aims to measure dust concentration in Bandung Regency and its risks to public health. This dust concentration measurement was carried out for 3 time periods (morning, afternoon, and evening) in 3 sub-districts based on differences in land use (agricultural, residential, and industrial). Public health data were obtained based on a questionnaire on perception of respiratory system disorders suffered by the community. The results of the measurement of dust concentration showed that the concentrations of dust respectively the highest were industrial sector, agricultural sector, and residential sector. In the industrial sector, PM2.5 and PM10 obtained were considered to exceed the quality standard, while the agricultural and residential sectors still met the quality standard. Correlation analysis showed that there was no significant relationship between dust concentrations on perception of respiratory system disorders. Comparative analysis of dust concentrations showed a significant difference between dust concentrations in one sector and another. Based on prevalence ratio analysis, it was found that the concentration of dust increased the possibility of respiratory system disorders by 1.091 times. HQ calculation showed 1.835 which indicates there is a possibility the adverse effects of dust concentration in the area will occur

Secondary structure in lung surfactant SP-B peptides: IR and CD studies of bulk and monolayer phases

AbstractPulmonary surfactant protein SP-B is known to facilitate adsorption and spreading of surfactant components across the air/water interface. This property appears essential for in vivo function in the alveolar subphase and at the air/alveolar surface. Three peptides with amino acid sequences based on SP-B containing predicted α-helical regions (SP-B1-20, SP-B9-36A, SP-B40-60A) have been synthesized to probe structure-function relationships and protein-lipid interaction in bulk phase and monolayer environments. IR and CD studies are reported along with traditional surface pressure-molecular area (π-A) isotherms and IR reflection-absorption spectroscopy (IRRAS) investigations conducted at the air/water interface. In bulk phase, helix-promoting environments (methanol and aqueous dispersions of lipid vesicles), SP-B1-20 and SP-B9-36A contained significant amounts of α-helical structure, whereas varying degrees of α-helix, random coil, and β-sheet were observed in aqueous solutions and monolayers. The most striking behavior was observed for SP-B9-36A, which displayed reversible surface pressure-induced β-sheet formation. Bulk phase lipid melting curves and monolayer experiments with peptide-lipid mixtures showed subtle differences in the degree of bulk phase interaction and substantial differences in peptide surface activity. The uniqueness of IRRAS is emphasized as the importance of evaluating secondary structure in both bulk phase and monolayer environments for lung surfactant peptide mimics is demonstrated

Uji Efektivitas Ekstrak Bakteri Simbion Lamun Enhalus SP. sebagai Bioinsektisida pada Kecoa Blatella Germanica di Laboratorium

Cockroach is a vector disease that lives in the home, restaurants, hotels, hospitals, warehouses, offices, libraries, and others. This insect is very close to human life. The way to control cockroach Blatella germanica is used of insecticides. Biological insecticides is one alternative vector control. Results photochemical content of active compounds contained in the seagrass bacteria Enhalus sp. such as terpenes, alkaloids and carotenoids that can be toxic to insects as an insecticide. This study was aimed to determine the effectiveness of bacterial symbionts of seagrass extracts Enhalus sp. as bioinsektisida on Blatella germanica cockroaches. The research was conducted in April-August 2013. The samples used for this study is isolate bacterial symbiont of seagrass Enhalus sp. Blatella germanica and cockroaches. Methods used are experimental laboratories. The number of samples used for this study is 920 crawly things. Based on probit analysis are obtained at a concentration of LC50 78.203% and LC90 88.078% present in concentrations. based on the results of ANOVA were no significant differences of various concentrations of bacterial extract as seagrass Enhalus sp bioinsektisida Blatella germanica cockroaches to death with a significance of p = 0.000. Communities can apply bacterial symbionts of seagrass extracts Enhalus sp. as bioinsektisida to kill a cockroach so as to reduce the number of diseases caused by cockroache

Studi Tentang Peran Serta Masyarakat Dalam Upaya Pencegahan Penyakit Malaria Di Puskesmas Rumbia Tengah Tahun 2016

Malaria terjadi di 106 Negara bahkan 3,3 milyar penduduk dunia tinggal di daerah beresiko tertularmalaria. Jumlah kasus malaria di dunia sebanyak 216 juta kasus, dimana 28 juta kasus terjadi di ASEAN. Tujuanumum penelitian ini adalah untuk mengetahui Studi Tentang Peran Serta Masyarakat Dalam Upaya PencegahanPenyakit Malaria Di Puskesmas Rumbia Tengah Tahun 2016. Penelitian ini bersifat Deskriptif Kuantitatif denganmenggunakan pendekatan survey. Populasi dalam penelitian ini adalah 285 kasus dan sampel di ambil dengancara random (acak), jumlah sampel sebanyak 164 responden. Variabel dalam penelitian ini yaitu pemakaiankelambu, pemasangan kawat kasa pada ventilasi rumah, pemakaian obat anti nyamuk dan pemberantasanperindukan nyamuk. Hasil penelitian menunjukkan bahwa jumlah pemakaian kelambu sebesar 64,6%,pemasangan kawat kasa sebesar 71,3%, pemakaian obat anti nyamuk sebesar 77,4% pemberantasan perindukannyamuk meliputi : pembersihan genangan air sebesar 54,9%, pembuatan saluran pembuangan air limbah (SPAL)sebesar 76,8% dan pembersihan semak belukar sebesar 74,4%

Laboratory Astrophysics Division of the AAS (LAD)

The purpose of the Laboratory Astrophysics Division (LAD) is to advance our understanding of the Universe through the promotion of fundamental theoretical and experimental research into the underlying processes that drive the Cosmos. LAD represents all areas of astrophysics and planetary sciences. The first new AAS Division in more than 30 years, the LAD traces its history back to the recommendation from the scientific community via the White Paper from the 2006 NASA-sponsored Laboratory Astrophysics Workshop. This recommendation was endorsed by the Astronomy and Astrophysics Advisory Committee (AAAC), which advises the National Science Foundation (NSF), the National Aeronautics and Space Administration (NASA), and the U.S. Department of Energy (DOE) on selected issues within the fields of astronomy and astrophysics that are of mutual interest and concern to the agencies. In January 2007, at the 209th AAS meeting, the AAS Council set up a Steering Committee to formulate Bylaws for a Working Group on Laboratory Astrophysics (WGLA). The AAS Council formally established the WGLA with a five-year mandate in May 2007, at the 210th AAS meeting. From 2008 through 2012, the WGLA annually sponsored Meetings in-a-Meeting at the AAS Summer Meetings. In May 2011, at the 218th AAS meeting, the AAS Council voted to convert the WGLA, at the end of its mandate, into a Division of the AAS and requested draft Bylaws from the Steering Committee. In January 2012, at the 219th AAS Meeting, the AAS Council formally approved the Bylaws and the creation of the LAD. The inaugural gathering and the first business meeting of the LAD were held at the 220th AAS meeting in Anchorage in June 2012. You can learn more about LAD by visiting its website at http://lad.aas.org/ and by subscribing to its mailing list

Reconstruction of Network Evolutionary History from Extant Network Topology and Duplication History

Genome-wide protein-protein interaction (PPI) data are readily available thanks to recent breakthroughs in biotechnology. However, PPI networks of extant organisms are only snapshots of the network evolution. How to infer the whole evolution history becomes a challenging problem in computational biology. In this paper, we present a likelihood-based approach to inferring network evolution history from the topology of PPI networks and the duplication relationship among the paralogs. Simulations show that our approach outperforms the existing ones in terms of the accuracy of reconstruction. Moreover, the growth parameters of several real PPI networks estimated by our method are more consistent with the ones predicted in literature.Comment: 15 pages, 5 figures, submitted to ISBRA 201

Advanced multivariate data analysis to determine the root cause of trisulfide bond formation in a novel antibody-peptide fusion

Product quality heterogeneities, such as a trisulfide bond (TSB) formation, can be influenced by multiple interacting process parameters. Identifying their root cause is a major challenge in biopharmaceutical production. To address this issue, this paper describes the novel application of advanced multivariate data analysis (MVDA) techniques to identify the process parameters influencing TSB formation in a novel recombinant antibody-peptide fusion expressed in mammalian cell culture. The screening dataset was generated with a high-throughput (HT) micro-bioreactor system (Ambr(TM) 15) using a design of experiments (DoE) approach. The complex dataset was firstly analyzed through the development of a multiple linear regression model focusing solely on the DoE inputs and identified the temperature, pH and initial nutrient feed day as important process parameters influencing this quality attribute. To further scrutinize the dataset, a partial least squares model was subsequently built incorporating both on-line and off-line process parameters and enabled accurate predictions of the TSB concentration at harvest. Process parameters identified by the models to promote and suppress TSB formation were implemented on five 7 L bioreactors and the resultant TSB concentrations were comparable to the model predictions. This study demonstrates the ability of MVDA to enable predictions of the key performance drivers influencing TSB formation that are valid also upon scale-up