Siloxane based Organic-Inorganic Hybrid Polymers and their Applications for Nanostructured Optical/Photonic Components

We have studied the preparation of organic-inorganic hybrid polymer precursors  by  sol-gel  technique  and  their  utilization  for  nanostructured  optical components for photonic applications. The gel polymer precursors were prepared from  siloxane  modified  by  polymerizable  acrylate  groups,  which  can  be processed  further  by  photopolymerization  process.  Molecular  structure characterizations by means of the FTIR measurements indicate the conversion of C=C  bonds  into  C-C  bonds  after  photopolymerization.  This  bond  co nversion produces  high  cross-linking  between  the  organic  and  inorganic  moieties, resulting  in  thermally  stable and chemically resistant thin polymer layer which provide  unique  advantages  of  this  material  for  particular  optical/photonic applications.  By  employing  laser  interference  technique,  gratings  with periodicity between 400-1000 nm have been successfully fabricated. Application of  those  sub-micron  periodicity  of  grating  structure  as  active  elements  in optically  pumped  polymer  laser  system  and  Surface Plasmon Resonance  (SPR) based  measurement  system  have  been  also  explored.  The  experimental  results therefore  also  show  the  potential  applications  of  this  hybrid  polymer  as  a building material for micro/nano-photonics components.

Siloxane Based Organic-Inorganic Hybrid Polymers and Their Applications for Nanostructured Optical/Photonic Components

We have studied the preparation of organic-inorganic hybrid polymer precursors by sol-gel technique and their utilization for nanostructured optical components for photonic applications. The gel polymer precursors were prepared from siloxane modified by polymerizable acrylate groups, which can be processed further by photopolymerization process. Molecular structure characterizations by means of the FTIR measurements indicate the conversion of C=C bonds into C-C bonds after photopolymerization. This bond co nversion produces high cross-linking between the organic and inorganic moieties, resulting in thermally stable and chemically resistant thin polymer layer which provide unique advantages of this material for particular optical/photonic applications. By employing laser interference technique, gratings with periodicity between 400-1000 nm have been successfully fabricated. Application of those sub-micron periodicity of grating structure as active elements in optically pumped polymer laser system and Surface Plasmon Resonance (SPR) based measurement system have been also explored. The experimental results therefore also show the potential applications of this hybrid polymer as a building material for micro/nano-photonics components

Remdesivir and three other drugs for hospitalised patients with COVID-19: final results of the WHO Solidarity randomised trial and updated meta-analyses.

BACKGROUND World Health Organization expert groups recommended mortality trials of four repurposed antiviral drugs - remdesivir, hydroxychloroquine, lopinavir, and interferon beta-1a - in patients hospitalized with coronavirus disease 2019 (Covid-19). METHODS We randomly assigned inpatients with Covid-19 equally between one of the trial drug regimens that was locally available and open control (up to five options, four active and the local standard of care). The intention-to-treat primary analyses examined in-hospital mortality in the four pairwise comparisons of each trial drug and its control (drug available but patient assigned to the same care without that drug). Rate ratios for death were calculated with stratification according to age and status regarding mechanical ventilation at trial entry. RESULTS At 405 hospitals in 30 countries, 11,330 adults underwent randomization; 2750 were assigned to receive remdesivir, 954 to hydroxychloroquine, 1411 to lopinavir (without interferon), 2063 to interferon (including 651 to interferon plus lopinavir), and 4088 to no trial drug. Adherence was 94 to 96% midway through treatment, with 2 to 6% crossover. In total, 1253 deaths were reported (median day of death, day 8; interquartile range, 4 to 14). The Kaplan-Meier 28-day mortality was 11.8% (39.0% if the patient was already receiving ventilation at randomization and 9.5% otherwise). Death occurred in 301 of 2743 patients receiving remdesivir and in 303 of 2708 receiving its control (rate ratio, 0.95; 95% confidence interval [CI], 0.81 to 1.11; P = 0.50), in 104 of 947 patients receiving hydroxychloroquine and in 84 of 906 receiving its control (rate ratio, 1.19; 95% CI, 0.89 to 1.59; P = 0.23), in 148 of 1399 patients receiving lopinavir and in 146 of 1372 receiving its control (rate ratio, 1.00; 95% CI, 0.79 to 1.25; P = 0.97), and in 243 of 2050 patients receiving interferon and in 216 of 2050 receiving its control (rate ratio, 1.16; 95% CI, 0.96 to 1.39; P = 0.11). No drug definitely reduced mortality, overall or in any subgroup, or reduced initiation of ventilation or hospitalization duration. CONCLUSIONS These remdesivir, hydroxychloroquine, lopinavir, and interferon regimens had little or no effect on hospitalized patients with Covid-19, as indicated by overall mortality, initiation of ventilation, and duration of hospital stay. (Funded by the World Health Organization; ISRCTN Registry number, ISRCTN83971151; ClinicalTrials.gov number, NCT04315948.)

Siloxane based Organic-Inorganic Hybrid Polymers and their Applications for Nanostructured Optical/Photonic Components

We have studied the preparation of organic-inorganic hybrid polymer precursors by sol-gel technique and their utilization for nanostructured optical components for photonic applications. The gel polymer precursors were prepared from siloxane modified by polymerizable acrylate groups, which can be processed further by photopolymerization process. Molecular structure characterizations by means of the FTIR measurements indicate the conversion of C=C bonds into C-C bonds after photopolymerization. This bond conversion produces high cross-linking between the organic and inorganic moieties, resulting in thermally stable and chemically resistant thin polymer layer which provide unique advantages of this material for particular optical/photonic applications. By employing laser interference technique, gratings with periodicity between 400-1000 nm have been successfully fabricated. Application of those sub-micron periodicity of grating structure as active elements in optically pumped polymer laser system and Surface Plasmon Resonance (SPR) based measurement system have been also explored. The experimental results therefore also show the potential applications of this hybrid polymer as a building material for micro/nano-photonics components

Siloxane based Organic-Inorganic Hybrid Polymers and their Applications for Nanostructured Optical/Photonic Components

We have studied the preparation of organic-inorganic hybrid polymer precursors  by  sol-gel  technique  and  their  utilization  for  nanostructured  optical components for photonic applications. The gel polymer precursors were prepared from  siloxane  modified  by  polymerizable  acrylate  groups,  which  can  be processed  further  by  photopolymerization  process.  Molecular  structure characterizations by means of the FTIR measurements indicate the conversion of C=C  bonds  into  C-C  bonds  after  photopolymerization.  This  bond  co nversion produces  high  cross-linking  between  the  organic  and  inorganic  moieties, resulting  in  thermally  stable and chemically resistant thin polymer layer which provide  unique  advantages  of  this  material  for  particular  optical/photonic applications.  By  employing  laser  interference  technique,  gratings  with periodicity between 400-1000 nm have been successfully fabricated. Application of  those  sub-micron  periodicity  of  grating  structure  as  active  elements  in optically  pumped  polymer  laser  system  and  Surface Plasmon Resonance  (SPR) based  measurement  system  have  been  also  explored.  The  experimental  results therefore  also  show  the  potential  applications  of  this  hybrid  polymer  as  a building material for micro/nano-photonics components.

Mapping genomic loci implicates genes and synaptic biology in schizophrenia

Schizophrenia has a heritability of 60-80%1, much of which is attributable to common risk alleles. Here, in a two-stage genome-wide association study of up to 76,755 individuals with schizophrenia and 243,649 control individuals, we report common variant associations at 287 distinct genomic loci. Associations were concentrated in genes that are expressed in excitatory and inhibitory neurons of the central nervous system, but not in other tissues or cell types. Using fine-mapping and functional genomic data, we identify 120 genes (106 protein-coding) that are likely to underpin associations at some of these loci, including 16 genes with credible causal non-synonymous or untranslated region variation. We also implicate fundamental processes related to neuronal function, including synaptic organization, differentiation and transmission. Fine-mapped candidates were enriched for genes associated with rare disruptive coding variants in people with schizophrenia, including the glutamate receptor subunit GRIN2A and transcription factor SP4, and were also enriched for genes implicated by such variants in neurodevelopmental disorders. We identify biological processes relevant to schizophrenia pathophysiology; show convergence of common and rare variant associations in schizophrenia and neurodevelopmental disorders; and provide a resource of prioritized genes and variants to advance mechanistic studies.11Nsciescopu

Mapping genomic loci implicates genes and synaptic biology in schizophrenia

Schizophrenia has a heritability of 60–80%1, much of which is attributable to common risk alleles. Here, in a two-stage genome-wide association study of up to 76,755 individuals with schizophrenia and 243,649 control individuals, we report common variant associations at 287 distinct genomic loci. Associations were concentrated in genes that are expressed in excitatory and inhibitory neurons of the central nervous system, but not in other tissues or cell types. Using fine-mapping and functional genomic data, we identify 120 genes (106 protein-coding) that are likely to underpin associations at some of these loci, including 16 genes with credible causal non-synonymous or untranslated region variation. We also implicate fundamental processes related to neuronal function, including synaptic organization, differentiation and transmission. Fine-mapped candidates were enriched for genes associated with rare disruptive coding variants in people with schizophrenia, including the glutamate receptor subunit GRIN2A and transcription factor SP4, and were also enriched for genes implicated by such variants in neurodevelopmental disorders. We identify biological processes relevant to schizophrenia pathophysiology; show convergence of common and rare variant associations in schizophrenia and neurodevelopmental disorders; and provide a resource of prioritized genes and variants to advance mechanistic studies