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Superglassy membranes synthesised by polymers of intrinsic microporosity (PIMs) suffer from physical aging and show poor gas permeance over time, especially thin membranes, due to the fast rearrangement of nonequilibrium polymer chains. Herein, we constructed a novel PIM-1 thin film nanocomposite membrane (TFN) using nanosized UiO-66−NH2 (≈10 nm)/carboxylated PIM-1 (cPIM-1) as the composite filler. Unlike conventional fillers, which interact with the polymer only via the surface, the UiO-66−NH2/cPIM-1 forms a stable three-dimensional (3D) network intertwining with the polymer chains, being very effective to impede chain relaxation, and thus physical aging. Nanosizing of UiO-66−NH2 was achieved by regulating the nucleation kinetics using carbon quantum dots (CQD) during the synthesis. This led to increased surface area, and hence more functional groups to bond with cPIM-1 (via hydrogen bonding between −NH2 and −COOH groups), which also improved interfacial compatibility between the 3D network and polymer chains avoiding defect formation. As a result, the novel TFN showed significantly improved performance in gas separation along with reduced aging (i.e. ≈6 % loss in CO2 permeability over 63 days); the aged membranes had a CO2 permeance of 2504 GPU and ideal selectivity values of 37.2 and 23.8 for CO2/N2 and CO2/CH4, respectively.

A novel approach to improve the initial performance as well as to prevent physical aging of superglassy high free volume polymer PIM-1 is reported. Bis(phenyl)fluorene-based polymer of intrinsic microporosity (Cardo-PIM-1) was used at different loadings in PIM-1 to fabricate thin film composite (TFC) membranes and freestanding membranes. The gas performances of both TFCs and thick freestanding membranes exhibited similar trends; higher CO2 permeance and higher CO2/CH4 selectivity at relatively low loadings (≤5 wt %). TFCs containing 5 wt % Cardo-PIM-1 achieved a CO2 permeance of (12600 ± 866 GPU), which corresponds to about a threefold increase as compared to the pristine TFC-PIM-1 membranes (2850 ± 254 GPU) and higher CO2/CH4 selectivity (14.6 ± 1.3) as compared to pure PIM-1 (10 ± 3). With regards to physical aging, PIM-1 TFC membranes experienced a 96 % reduction in CO2 permeance after 1 year. However, for the TFCs containing 5 wt % cardo the reduction was considerably lower (59%) and all took place at an initial stage of up to 37 days, remaining at a good and stable CO2 permeance of c.a. 5000 GPU for the remaining testing period of up to one year.

This report presents a model state legislative bill to provide for the special needs of gifted and talented students. The model bill utilizes a "best practices" framework and attempts to be fiscally responsible and provide maximum flexibility while meeting the needs of gifted and talented students. The model legislation itself begins with a statement of purpose followed by a section defining the population of gifted and talented students and stating a policy of nondiscrimination. A section on supervision of gifted and talented programs covers the Office of State Coordinator, the duties of the Office of State Coordinator, and collaboration with the State Advisory Board. The section on the State Advisory Board for Gifted and Talented Education includes guidelines for Board establishment, Board membership, and Board duties. Specific program responsibilities and criteria are presented in the section on gifted and talented programs. In addition, a definition and nondiscrimination policy statement are offered on the issue of traditionally underserved populations. The final section makes appropriation recommendations. Following the model legislation, analysis is provided for each of the Bill's sections. (DB)

The polymer of intrinsic microporosity PIM-1 was synthesized with different topologies and negligible network content. A more rapid heating rate from room temperature yielded a predominantly di-substituted PIM-1 (D-PIM-1), whereas a marginally lower heating rate produced a more branched structure (B-PIM-1). Both polymers were acid-hydrolyzed to give carboxylic acid functionalization (cPIM-1), as indicated by FT-IR, 1H NMR, and elemental analysis. Both PIM-1 and cPIM-1 were processed into self-supported membranes and into thin film composite (TFC) membranes on a polyacrylonitrile support. For a 70% hydrolyzed polymer (D-cPIM-1-70%), the initial CO2 permeance reached 7700 GPU, with ideal selectivity of 56 for CO2/N2 and 37 for CO2/CH4. D-PIM-1 and D-cPIM-1-70% showed 85% and 52% CO2 permeance drop after 60 days’ aging, respectively. B-PIM-1, with initial CO2 permeance of 3100 GPU and ideal selectivity of 19 for CO2/N2 and 11 for CO2/CH4, showed only a 65% decrease. Polymer that was both branched and hydrolyzed (B-cPIM-1-73&81%), with CO2 permeance of 3200 GPU and selectivity of 64 for CO2/N2 and 45 for CO2/CH4, showed no decrease of CO2 permeance after 60 days. The branched structure is crucial for reducing membrane aging. Plasticization gave rise to reduced selectivity in mixed gas experiments, but nevertheless TFC membranes prepared from B-cPIM-1-81% were able to concentrate CO2 to 38% from a 10% CO2/90% N2 mixture at 4.8 bar.

The recycling of depleted high global warming mixtures of fluorinated gases (F-gases) with close-boiling or azeotropic behavior requires advanced separation processes to obtain effectively the pure components. Herein, several types of PIM-1 membranes were tested for the first time towards the separation of hydrofluorocarbons and hydrofluoroolefins, showing extraordinarily high permeability coefficients for the value-added difluoromethane (R-32), up to 4100 barrer, coupled with high selectivity for the F-gas pairs of interest. Additionally, the solubility of selected F-gases in PIM-1 was measured and fitted to the dual-mode and Guggenheim, Anderson and de Boer sorption models. The separation performance of the standard PIM-1 and a highly branched PIM-1 was examined with the mixture R-410A (containing R-32 and pentafluoroethane R-125) to assess the influence of the membrane topology on the mixed-gas permeation properties over time (physical aging). Considering that the branched PIM-1 membrane was the least impacted by the aging phenomena, it was used to recover high purity R-32 (concentration in the permeate side as high as 98.9 vol % was achieved) from refrigerant gas mixtures R-410A and R–454B (mixture of R-32 and R-1234yf) in continuous long-term experiments. Results showed the great potential of PIM-1 membranes for the separation of R-32 from refrigerant mixtures collected from end-of-life equipment.

Loss of free volume over time (i.e. aging) is the main hurdle towards the commercial use of super glassy polymers for gas separation membranes. Aging takes place at a much faster rate in polymeric thin films, with permeability reductions of over 50% in only a few days. In this work 2D reduced holey graphene oxide (rHGO) nanosheets containing amine groups were added into thin films of the super-glassy polymer of intrinsic microporosity PIM-1. At filler loadings of 1 wt% of rHGO-tris(4-aminophenyl)amine, the CO2 permeance after 1 year of physical aging was 846 ± 37 GPU, which remained very close to that of the fresh membrane tested right after preparation (1050 ± 70 GPU), and was double that of 1 year-aged purely PIM-1 thin film composite membranes (432 ± 4 GPU). Membranes with lower filler concentrations of 0.1 wt% showed CO2 permeance values of 604 ± 34 GPU after 1 year of aging, but they aged quite rapidly; the initial CO2 permeance values of the fresh thin film nanocomposite (TFN) membrane at filler loading of 0.1 wt% was 3351 ± 662 GPU. The aging behaviour was also investigated in several tens of micrometres thick membranes (up to 2 years) for filler loadings of 0.1 wt% and the gas separation performance showed similar tendencies to that of thin films; leading to higher CO2 permeability without sacrificing CO2/CH4 selectivity.

We present the open-source Bayesian Atmospheric Radiative Transfer (BART) retrieval package, which produces estimates and uncertainties for an atmosphere's thermal profile and chemical abundances from observations. Several BART components are also stand-alone packages, including the parallel Multi-Core Markov chain Monte Carlo (MC3), which implements several Bayesian samplers; a line-by-line radiative-transfer model, transit; a code that calculates Thermochemical Equilibrium Abundances, TEA; and a test suite for verifying radiative-transfer and retrieval codes, BARTTest. The codes are in Python and C. BART and TEA are under a Reproducible Research (RR) license, which requires reviewed-paper authors to publish a compendium of all inputs, codes, and outputs supporting the paper's scientific claims. BART and TEA produce the compendium's content. Otherwise, these codes are under permissive open-source terms, as are MC3 and BARTTest, for any purpose. This paper presents an overview of the code, BARTTest, and an application to eclipse data for exoplanet HD 189733 b. Appendices address RR methodology for accelerating science, a reporting checklist for retrieval papers, the spectral resolution required for synthetic tests, and a derivation of the effective sample size required to estimate any Bayesian posterior distribution to a given precision, which determines how many iterations to run. Paper II, by Cubillos et al., presents the underlying radiative-transfer scheme and an application to transit data for exoplanet HAT-P-11b. Paper III, by Blecic et al., discusses the initialization and post-processing routines, with an application to eclipse data for exoplanet WASP-43b. We invite the community to use and improve BART and its components at http://GitHub.com/ExOSPORTS/BART/., Comment: 38 pages, 17 figures, submitted to The Planetary Science Journal

This and companion papers by Harrington et al. and Blecic et al. present the Bayesian Atmospheric Radiative Transfer (BART) code, an open-source, open-development package to characterize extrasolar-planet atmospheres. BART combines a thermochemical equilibrium abundances (TEA), a radiative-transfer (Transit), and a Bayesian statistical (MC3) module to constrain atmospheric temperatures and molecular abundances for given spectroscopic observations. Here, we describe the Transit radiative-transfer package, an efficient line-by-line radiative-transfer C code for one-dimensional atmospheres, developed by P. Rojo and further modified by the UCF exoplanet group. This code produces transmission and hemisphere-integrated emission spectra. Transit handles line-by-line opacities from HITRAN, Partridge \& Schwenke ({\water}), Schwenke (TiO), and Plez (VO); and collision-induced absorption from Borysow, HITRAN, and ExoMol. Transit emission-spectra models agree with models from C. Morley (priv. comm.) within a few percent. We applied BART to the {\Spitzer} and {\Hubble} transit observations of the Neptune-sized planet HAT-P-11b. Our results generally agree with those from previous studies, constraining the {\water} abundance and finding an atmosphere enhanced in heavy elements. Different conclusions start to emerge when we make different assumptions from other studies. The BART source code and documentation are available at https://github.com/exosports/BART., Comment: Accepted for publication at PSJ

This and companion papers by Harrington et al. 2021, submitted and Cubillos et al. 2021, submitted describe an open-source retrieval framework, Bayesian Atmospheric Radiative Transfer (BART), available to the community under the reproducible-research license via https://github.com/exosports/BART . BART is a radiative-transfer code (transit, https://github.com/exosports/transit , Rojo 2009, 2009ASPC..420..321R), initialized by the Thermochemical Equilibrium Abundances (TEA, https://github.com/dzesmin/TEA , Blecic et al. 2016, arXiv:1505.06392) code, and driven through the parameter phase space by a differential-evolution Markov-chain Monte Carlo (MC3, https://github.com/pcubillos/mc3 , Cubillos et al. 2017, arXiv:1610.01336) sampler. In this paper we give a brief description of the framework, and its modules that can be used separately for other scientific purposes; outline the retrieval analysis flow; present the initialization routines, describing in detail the atmospheric profile generator and the temperature and species parameterizations; and specify the post-processing routines and outputs, concentrating on the spectrum band integrator, the best-fit model selection, and the contribution functions. We also present an atmospheric analysis of WASP-43b secondary eclipse data obtained from space- and ground-based observations. We compare our results with the results from the literature, and investigate how the inclusion of additional opacity sources influence the best-fit model., Comment: 16 pages, 14 figures

Background: Cutibacterium acnes is a commensal, gram-positive, facultatively anaerobic bacillus that resides in the dermis. Historically thought to be a contaminant when identified on cultured specimens, recent advances in diagnostic technology have now implicated it as the most common organism responsible for postoperative shoulder infections. Despite a recognition of the role of this organism and a significant research interest in recent years, there is clear lack of consensus guideline on strategies to prevent, diagnose, and treat postoperative shoulder infection. Method: The electronic databases PubMed, MEDLINE, CINAHL, Scopus, and Web of Science were searched in March 2020. All experimental and nonexperimental studies that investigate C acnes in shoulder surgery were included. Inclusion was limited to articles published after 2000 and written in English; reviews, gray literature, or abstracts were excluded. A total of 70 studies were included in this review. This scoping review was performed in accordance with the Extended Preferred Reporting Items of Systematic Reviews and Meta-Analyses Statement for Scoping Reviews (PRISMA-ScR). Results: Standard surgical prophylactic regimens such as intravenous antibiotics and topical chlorhexidine are ineffective at removing C acnes from the deep layer of the dermis, and there is a shift toward using topical benzoyl peroxide with significantly improved efficacy. An improved understanding of the bacteria has demonstrated that a prolonged culture time of up to 14 days is needed, especially in cases of established infection. Advances in diagnostics such as sonication and molecular-based testing are promising. Although usually thought to be susceptible to a broad range of antibiotics, resistance is emerging to clindamycin. An improved understanding of its ability to form a biofilm highlights the difficulty in treating an established infection. Conclusion: The role of C acnes causing postoperative infection following shoulde

Bone healing is a complicated process of tissue regeneration that is influenced by multiple biological and biomechanical processes. In a minority of cases, these physiological processes are complicated by issues such as nonunion and/or fracture-related infection (FRI). Based on a select few in vivo experimental animal studies, construct stability is considered an important factor influencing both prevention and treatment of FRI. Stephan Perren played a pivotal role in the evolution of our current understanding of the critical relationship between biomechanics, fracture healing and infection. Furthermore, his concept of strain theory and the process of fracture healing is familiar to several generations of surgeons and has influenced implant development and design for the past 50 years. In this review we describe the role of biomechanical stability on fracture healing, and provide a detailed analysis of the preclinical studies addressing this in the context of FRI. Furthermore, we demonstrate how Perren's concepts of stability are still applied to current surgical techniques to aid in the prevention and treatment of FRI. Finally, we highlight the key knowledge gaps in the underlying basic research literature that need to be addressed as we continue to optimize patient care.

Family planning programs are believed to have substantial long-term benefits for women's health and well-being, yet few studies have established either extent or direction of long-term effects. The Matlab, Bangladesh, maternal and child health/family planning (MCH/FP) program afforded a 12-y period of well-documented differential access to services. We evaluate its impacts on women's lifetime fertility, adult health, and economic outcomes 35 y after program initiation. We followed 1,820 women who were of reproductive age during the differential access period (born 1938-1973) from 1978 to 2012 using prospectively collected data from the Matlab Health and Demographic Surveillance System and the 1996 and 2012 Matlab Health and Socioeconomic Surveys. We estimated intent-to-treat single-difference models comparing treatment and comparison area women. MCH/FP significantly increased contraceptive use, reduced completed fertility, lengthened birth intervals, and reduced age at last birth, but had no significant positive impacts on health or economic outcomes. Treatment area women had modestly poorer overall health (+0.07 SD) and respiratory health (+0.12 SD), and those born 1950-1961 had significantly higher body mass index (BMI) in 1996 (0.76 kg/m2) and 2012 (0.57 kg/m2); fewer were underweight in 1996, but more were overweight or obese in 2012. Overall, there was a +2.5 kg/m2 secular increase in BMI. We found substantial changes in lifetime contraceptive and fertility behavior but no long-term health or economic benefits of the program. We observed modest negative health impacts that likely result from an accelerated nutritional transition among treated women, a transition that would, in an earlier context, have been beneficial.

PIM-1/holey graphene oxide (GO) mixed matrix membranes (MMMs) have been prepared and their gas separation performance for CO2/CH4 mixtures assessed. Nanopores have been created in the basal plane of gas-impermeable GO by chemical etching reactions, and the resulting holey flakes have been further chemically functionalized, either with octadecylamine (ODA) or with PIM-1 moieties, to aid their dispersion in PIM-1. It is found that nanopores barely promote gas transport through the graphene-like nanofiller for fresh membranes (tested right after preparation); however, the prepared hybrid PIM-1/holey GO membranes exhibit higher CO2 permeability and CO2/CH4 selectivity than the pure polymer membrane 150 days after preparation and 13 and 15% higher CO2 permeability for filler contents of 0.1% of octadecylamine-functionalized holey GO and 1% of (PIM-1)-functionalized holey GO, respectively. The most significant improvement is observed for the mitigation of physical aging, as MMMs using 10% of (PIM-1)-functionalized holey GO nanofillers are capable of maintaining up to 70% of their initial CO2 permeability after 150 days, whereas only 53% is kept for pure PIM-1 after the same period. The gas permeability of the nanofiller has been rationalized with the aid of the Maxwell–Wagner–Sillars equation.

Introduction: Fracture-related infection (FRI) is a serious complication related to orthopedic trauma, both from an infectious disease and a surgical point of view. The lack of scientific data with respect to diagnostic criteria and treatment principles of this entity has hampered efforts for an evidence-based approach and, as such, practices to prevent and treat FRI are often extrapolated from peri-prosthetic joint infection (PJI) literature. Recently, consensus guidelines were developed with respect to prevention, diagnosis and treatment of FRI. Areas covered: This review will define FRI and approaches to prevent and treat this complication will be discussed, with an emphasis on antimicrobial and surgical considerations. Guidelines focusing on FRI will be highlighted and aspects of pre-clinical research with imminent translational potential described. Expert opinion: New strategies are currently under investigation to improve the outcome of this sometimes-devastating complication. Local delivery of antimicrobials seems to be a promising approach; however, further high-quality clinical research is necessary to demonstrate efficacy. Delivery mechanisms for local antimicrobials include polymethyl methacrylate, implant coatings, collagen fleece, hydrogels and ceramics. The reintroduction of antimicrobials such as bacteriophage therapy has demonstrated promise in the management of drug-resistant organisms.

Introduction: Plasma biomarkers for Alzheimer's disease (AD) diagnosis/stratification are a "Holy Grail" of AD research and intensively sought; however, there are no well-established plasma markers.Methods: A hypothesis-led plasma biomarker search was conducted in the context of international multicenter studies. The discovery phase measured 53 inflammatory proteins in elderly control (CTL; 259), mild cognitive impairment (MCI; 199), and AD (262) subjects from AddNeuroMed.Results: Ten analytes showed significant intergroup differences. Logistic regression identified five (FB, FH, sCR1, MCP-1, eotaxin-1) that, age/APOe4 adjusted, optimally differentiated AD and CTL (AUC: 0.79), and three (sCR1, MCP-1, eotaxin-1) that optimally differentiated AD and MCI (AUC: 0.74). These models replicated in an independent cohort (EMIF; AUC 0.81 and 0.67). Two analytes (FB, FH) plus age predicted MCI progression to AD (AUC: 0.71).Discussion: Plasma markers of inflammation and complement dysregulation support diagnosis and outcome prediction in AD and MCI. Further replication is needed before clinical translation. (C) 2019 The Authors. Published by Elsevier Inc. on behalf of the Alzheimer's Association. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).

Throughout history, mankind has made music. While music is artistic, it is also scientific and informed by natural occurrences within the physical world. Mathematical relationships between frequencies, the harmonic series, the materials necessary to build musical instruments, and naturally measured time provide bases for the musical elements of pitch, timbre, and rhythm. Though scientific discovery can inform the practice of music, the origin of music cannot be explained through scientific or evolutionary means because music is not a necessity for survival. The fact that music does exist and has natural bases suggests that music is designed, and its elements were placed in the physical world by a Creator who is beyond that which is physical.

We present {\em Spitzer} secondary-eclipse observations of the hot Jupiter HAT-P-13 b in the 3.6 {\micron} and 4.5 {\micron} bands. HAT-P-13 b inhabits a two-planet system with a configuration that enables constraints on the planet's second Love number, \math{k\sb{2}}, from precise eccentricity measurements, which in turn constrains models of the planet's interior structure. We exploit the direct measurements of \math{e \cos \omega} from our secondary-eclipse data and combine them with previously published radial velocity data to generate a refined model of the planet's orbit and thus an improved estimate on the possible interval for \math{k\sb{2}}. We report eclipse phases of \math{0.49154 \pm 0.00080} and \math{0.49711 \pm 0.00083} and corresponding \math{e \cos \omega} estimates of \math{-0.0136 \pm 0.0013} and \math{-0.0048 \pm 0.0013}. Under the assumptions of previous work, our estimate of \math{k\sb{2}} of 0.81 {\pm} 0.10 is consistent with the lower extremes of possible core masses found by previous models, including models with no solid core. This anomalous result challenges both interior models and the dynamical assumptions that enable them, including the essential assumption of apsidal alignment. We also report eclipse depths of 0.081\% {\pm} 0.008\% in the 3.6 {\micron} channel and 0.088 \% {\pm} 0.028 \% in the 4.5 {\micron} channel. These photometric results are non-uniquely consistent with solar-abundance composition without any thermal inversion., Comment: Accepted for publication by The Astrophysical Journal December 12, 2016

Chemically-induced protein association is involved in key regulatory pathways throughout the body. Many natural products exert their downstream effect by the stabilisation of naturally occurring interactions, either by an allosteric effect or by the direct binding of two distinct protein partners. The targeting of these interactions by small-molecules is a relatively under developed field, with the inhibition of existing protein-protein interactions (PPIs) a more investigated target. One such method to investigate PPI inhibition is a bacterial reverse two-hybrid system (RTHS), which has been successfully coupled to a split-intein based library of cyclic peptides to identify novel inhibitors (split-intein circular ligation of peptides and proteins, SICLOPPS). Here, the existing RTHS technology was rebuilt to enable the screening of cyclic peptides for their ability to induce dimerisation of two target proteins. The well-studied mTOR-FKBP12 interaction, with heterodimerisation induced by the natural product rapamycin, was used to build and validate a novel two-hybrid system. This utilises the tetracycline repressor to reverse the transcriptional control from the RTHS, leading to a selectable phenotype upon dimerisation. Rapamycin addition successfully results in the association of these target proteins, leading to the downstream expression of two essential reporter genes and a fluorescent protein. This rapamycin-dependent interaction can be identified both by an agarbased growth assay, and a liquid media-based fluorescent assay. A large number of SICLOPPS libraries were screened with little success at replicating the action of brapamycin. The SICLOPPS technology was optimised and expanded, enabling an improved screening platform for the future.

Background. The epidemic of sexually transmitted hepatitis C virus (HCV) infection among human immunodeficiency virus (HIV)-infected men who have sex with men (MSM) has been documented for over a decade. Despite this, there is no consensus as to the risk factors for sexual acquisition of HCV in these men. Methods. We obtained paired semen and blood samples at 2-week intervals from HIV-infected MSM with recent and chronic HCV infection and quantified HCV in semen. Results. Hepatitis C virus was quantified in 59 semen specimens from 33 men. Hepatitis C virus was shed in 16 (27%) of semen specimens from 11 (33%) of the men. Median HCV viral load (VL) in semen was 1.49 log10 IU/mL. Hepatitis C virus VL in blood was significantly higher at the time of HCV shedding in semen than when HCV shedding in semen was not detected (P = .002). Furthermore, there was a significant correlation between the HCV VL in blood and semen overall (rs = 0.41; P = .001), and in the subgroup with recent HCV infection (rs = 0.37; P = .02), but not in the subgroup with chronic HCV infection (rs = 0.34; P = .1). Conclusions. One third of HIV-infected MSM coinfected with HCV shed HCV into their semen. Based on the HCV VL in semen in this study, an average ejaculate would deliver up to 6630 IU of virus into the rectum of the receptive partner. Therefore, our data strongly support that condoms should be used during anal intercourse among MSM to prevent transmission of HCV.

Aminoacyl-tRNA synthetases (aaRSs) play a key role in deciphering the genetic message by producing charged tRNAs and are equipped with proofreading mechanisms to ensure correct pairing of tRNAs with their cognate amino acid. Duplicated aaRSs are very frequent in Nature, with 25,913 cases observed in 26,837 genomes. The oligomeric nature of many aaRSs raises the question of how the functioning and oligomerization of duplicated enzymes is organized. We characterized this issue in a model prokaryotic organism that expresses two different threonyl-tRNA synthetases, responsible for Thr-tRNAThr synthesis: one accurate and constitutively expressed (T1) and another (T2) with impaired proofreading activity that also generates mischarged Ser-tRNAThr. Low zinc promotes dissociation of dimeric T1 into monomers deprived of aminoacylation activity and simultaneous induction of T2, which is active for aminoacylation under low zinc. T2 either forms homodimers or heterodimerizes with T1 subunits that provide essential proofreading activity in trans. These findings evidence that in organisms with duplicated genes, cells can orchestrate the assemblage of aaRSs oligomers that meet the necessities of the cell in each situation. We propose that controlled oligomerization of duplicated aaRSs is an adaptive mechanism that can potentially be expanded to the plethora of organisms with duplicated oligomeric aaRSs.

Aminoacyl-tRNA synthetases (aaRSs) play a key role in deciphering the genetic message by producing charged tRNAs and are equipped with proofreading mechanisms to ensure correct pairing of tRNAs with their cognate amino acid. Duplicated aaRSs are very frequent in Nature, with 25,913 cases observed in 26,837 genomes. The oligomeric nature of many aaRSs raises the question of howthe functioning and oligomerization of duplicated enzymes is organized. We characterized this issue in a model prokaryotic organism that expresses two different threonyl-tRNA synthetases, responsible for Thr-tRNAThr synthesis: one accurate and constitutively expressed (T1) and another (T2) with impaired proofreading activity that also generates mischarged Ser-tRNAThr. Low zinc promotes dissociation of dimeric T1 into monomers deprived of aminoacylation activity and simultaneous induction of T2, which is active for aminoacylation under low zinc. T2 either forms homodimers or heterodimerizes with T1 subunits that provide essential proofreading activity in trans. These findings evidence that in organisms with duplicated genes, cells can orchestrate the assemblage of aaRSs oligomers that meet the necessities of the cell in each situation. We propose that controlled oligomerization of duplicated aaRSs is an adaptive mechanism that can potentially be expanded to the plethora of organisms with duplicated oligomeric aaRSs

With an equilibrium temperature of 1200 K, TrES-1 is one of the coolest hot Jupiters observed by {\Spitzer}. It was also the first planet discovered by any transit survey and one of the first exoplanets from which thermal emission was directly observed. We analyzed all {\Spitzer} eclipse and transit data for TrES-1 and obtained its eclipse depths and brightness temperatures in the 3.6 {\micron} (0.083 % {\pm} 0.024 %, 1270 {\pm} 110 K), 4.5 {\micron} (0.094 % {\pm} 0.024 %, 1126 {\pm} 90 K), 5.8 {\micron} (0.162 % {\pm} 0.042 %, 1205 {\pm} 130 K), 8.0 {\micron} (0.213 % {\pm} 0.042 %, 1190 {\pm} 130 K), and 16 {\micron} (0.33 % {\pm} 0.12 %, 1270 {\pm} 310 K) bands. The eclipse depths can be explained, within 1$\sigma$ errors, by a standard atmospheric model with solar abundance composition in chemical equilibrium, with or without a thermal inversion. The combined analysis of the transit, eclipse, and radial-velocity ephemerides gives an eccentricity $e = 0.033^{+0.015}_{-0.031}$, consistent with a circular orbit. Since TrES-1's eclipses have low signal-to-noise ratios, we implemented optimal photometry and differential-evolution Markov-chain Monte Carlo (MCMC) algorithms in our Photometry for Orbits, Eclipses, and Transits (POET) pipeline. Benefits include higher photometric precision and \sim10 times faster MCMC convergence, with better exploration of the phase space and no manual parameter tuning., Comment: 17 pages, Accepted for publication in ApJ

The plant-pathogenic fungus Mycosphaerella graminicola (asexual stage: Septoria tritici) causes septoria tritici blotch, a disease that greatly reduces the yield and quality of wheat. This disease is economically important in most wheat-growing areas worldwide and threatens global food production. Control of the disease has been hampered by a limited understanding of the genetic and biochemical bases of pathogenicity, including mechanisms of infection and of resistance in the host. Unlike most other plant pathogens, M. graminicola has a long latent period during which it evades host defenses. Although this type of stealth pathogenicity occurs commonly in Mycosphaerella and other Dothideomycetes, the largest class of plant-pathogenic fungi, its genetic basis is not known. To address this problem, the genome of M. graminicolawas sequenced completely. The finished genome contains 21 chromosomes, eight of which could be lost with no visible effect on the fungus and thus are dispensable. This eight-chromosome dispensome is dynamic in field and progeny isolates, is different from the core genome in gene and repeat content, and appears to have originated by ancient horizontal transfer from an unknown donor. Synteny plots of the M. graminicola chromosomes versus those of the only other sequenced Dothideomycete, Stagonospora nodorum, revealed conservation of gene content but not order or orientation, suggesting a high rate of intra-chromosomal rearrangement in one or both species. This observed “mesosynteny” is very different from synteny seen between other organisms. A surprising feature of the M. graminicolagenome compared to other sequenced plant pathogens was that it contained very few genes for enzymes that break down plant cell walls, which was more similar to endophytes than to pathogens. The stealth pathogenesis of M. graminicola probably involves degradation of proteins rather than carbohydrates to evade host defenses during the biotrophic stage of infection and may

This article empirically demonstrates the use of fine resolution satellite-based aerosol optical depth (AOD) to develop time and space resolved estimates of ambient particulate matter (PM) ≤2.5 μm and ≤10 μm in aerodynamic diameters (PM2.5 and PM10, respectively). AOD was computed at three different spatial resolutions, i.e., 2 km (means 2 km × 2 km area at nadir), 5 km, and 10 km, by using the data from MODerate Resolution Imaging Spectroradiometer (MODIS), aboard the Terra and Aqua satellites. Multiresolution AOD from MODIS (AODMODIS) was compared with the in situ measurements of AOD by NASA’s AErosol RObotic NETwork (AERONET) sunphotometer (AODAERONET) at Bondville, IL, to demonstrate the advantages of the fine resolution AODMODIS over the 10-km AODMODIS, especially for air quality prediction. An instrumental regression that corrects AODMODIS for meteorological conditions was used for developing a PM predictive model. The 2-km AODMODIS aggregated within 0.025◦ and 15-min intervals shows the best association with the in situ measurements of AODAERONET. The 2-km AODMODIS seems more promising to estimate time and space resolved estimates of ambient PM than the 10-km AODMODIS, because of better location precision and a significantly greater number of data points across geographic space and time. Utilizing the collocated AODMODIS and PM data in Cleveland, OH, a regression model was developed for predicting PM for all AODMODIS data points. Our analysis suggests that the slope of the 2-km AODMODIS (instrumented on meteorological conditions) is close to unity with the PM monitored on the ground. These results should be interpreted with caution, because the slope of AODMODIS ranges from 0.52 to 1.72 in the site-specific models. In the cross validation of the overall model, the root mean square error (RMSE) of PM10 was smaller (2.04 μg/m3 in overall model) than that of PM2.5 (2.5 μg/m3). The predicted PM in the AODMODIS data (~2.34 million data points) was utilized to deve

Ultraviolet, optical, and near-infrared photometry and optical spectroscopy of the broad-lined Type Ic supernova (SN) 2009bb are presented, following the flux evolution from -10 to +285 days past B-band maximum. Thanks to the very early discovery, it is possible to place tight constraints on the SN explosion epoch. The expansion velocities measured from near maximum spectra are found to be only slightly smaller than those measured from spectra of the prototype broad-lined SN 1998bw associated with GRB 980425. Fitting an analytical model to the pseudobolometric light curve of SN 2009bb suggests that 4.1 +/- 1.9M(circle dot) of material was ejected with 0.22 +/- 0.06 M(circle dot) of it being (56)Ni. The resulting kinetic energy is 1.8 +/- 0.7 x 10(52) erg. This, together with an absolute peak magnitude of M(B) = -18.36 +/- 0.44, places SN 2009bb on the energetic and luminous end of the broad-lined Type Ic (SN Ic) sequence. Detection of helium in the early time optical spectra accompanied with strong radio emission and high metallicity of its environment makes SN 2009bb a peculiar object. Similar to the case for gamma-ray bursts (GRBs), we find that the bulk explosion parameters of SN 2009bb cannot account for the copious energy coupled to relativistic ejecta, and conclude that another energy reservoir (a central engine) is required to power the radio emission. Nevertheless, the analysis of the SN 2009bb nebular spectrum suggests that the failed GRB detection is not imputable to a large angle between the line-of-sight and the GRB beamed radiation. Therefore, if a GRB was produced during the SN 2009bb explosion, it was below the threshold of the current generation of gamma-ray instruments., authorCount :27

Solo show.

The plant-pathogenic fungus Mycosphaerella graminicola (asexual stage: Septoria tritici) causes septoria tritici blotch, a disease that greatly reduces the yield and quality of wheat. This disease is economically important in most wheat-growing areas worldwide and threatens global food production. Control of the disease has been hampered by a limited understanding of the genetic and biochemical bases of pathogenicity, including mechanisms of infection and of resistance in the host. Unlike most other plant pathogens, M. graminicola has a long latent period during which it evades host defenses. Although this type of stealth pathogenicity occurs commonly in Mycosphaerella and other Dothideomycetes, the largest class of plant-pathogenic fungi, its genetic basis is not known. To address this problem, the genome of M. graminicola was sequenced completely. The finished genome contains 21 chromosomes, eight of which could be lost with no visible effect on the fungus and thus are dispensable. This eight-chromosome dispensome is dynamic in field and progeny isolates, is different from the core genome in gene and repeat content, and appears to have originated by ancient horizontal transfer from an unknown donor. Synteny plots of the M. graminicola chromosomes versus those of the only other sequenced Dothideomycete, Stagonospora nodorum, revealed conservation of gene content but not order or orientation, suggesting a high rate of intra-chromosomal rearrangement in one or both species.This observed “mesosynteny” is very different from synteny seen between other organisms. A surprising feature of the M. graminicola genome compared to other sequenced plant pathogens was that it contained very few genes for enzymes that break down plant cell walls, which was more similar to endophytes than to pathogens. The stealth pathogenesis of M. graminicola probably involves degradation of proteins rather than carbohydrates to evade host defenses during the biotrophic stage of infection and ma

Ultraviolet, optical, and near-infrared photometry and optical spectroscopy of the broad-lined Type Ic supernova (SN) 2009bb are presented, following the flux evolution from -10 to +285 days past B-band maximum. Thanks to the very early discovery, it is possible to place tight constraints on the SN explosion epoch. The expansion velocities measured from near maximum spectra are found to be only slightly smaller than those measured from spectra of the prototype broad-lined SN 1998bw associated with GRB 980425. Fitting an analytical model to the pseudo-bolometric light curve of SN 2009bb suggests that 4.1+-1.9 Msun of material was ejected with 0.22 +-0.06 Msun of it being 56Ni. The resulting kinetic energy is 1.8+-0.7x10^52 erg. This, together with an absolute peak magnitude of MB=-18.36+-0.44, places SN 2009bb on the energetic and luminous end of the broad-lined Type Ic (SN Ic) sequence. Detection of helium in the early time optical spectra accompanied with strong radio emission, and high metallicity of its environment makes SN 2009bb a peculiar object. Similar to the case for GRBs, we find that the bulk explosion parameters of SN 2009bb cannot account for the copious energy coupled to relativistic ejecta, and conclude that another energy reservoir (a central engine) is required to power the radio emission. Nevertheless, the analysis of the SN 2009bb nebular spectrum suggests that the failed GRB detection is not imputable to a large angle between the line-of-sight and the GRB beamed radiation. Therefore, if a GRB was produced during the SN 2009bb explosion, it was below the threshold of the current generation of gamma-ray instruments., Comment: Accepted for publication in ApJ

I was invited by Birmingham City University, to extend the work exhibited previously at Sheffield and Hallam University (Precious in thy sight)and exhibit it at the Birmingham City University. It was an extensive solo painting exhibition, with approx 70 pieces, ranging from 20cm x 20cm to 20ft x 11ft, mixed media on paper To launch the exhibition I gave a lecture about my practise.

Gary Powell was asked to submit a collaborative project for the exhibition 'Draw'. 'Draw' was an exhibition that celebrated the crossover between design, moving image, illustration and Fine Art. lllustration, digital drawing, chance and the infinite come together in a series of collaborations between practitioners and students showing work with similar themes and starting points. 'Draw' was a celebration of drawing as both process and outcome – from design to graphic novels, film, fine art and illustration, from quick and functional sketches to epic fictitious imaginings.

Andrew Foster delivered the keynote at this nternational illustration conference. Organised annually by UCF's MA in Illustration: Authorial Practice. The Open Forum took place at the Woodlane Campus in Falmouth. The event was chaired by Amelia Johnstone with main speakers, Jonathon Rosen, Bill Bragg, Graham Rawle, Matthew Richardson and additional guests, Anna Bhushan, Andrew Foster and David Kerr. Through a day of presentations and discussion, attendees had the opportunity to explore enterprising initiatives and new autonomies in illustration including special consideration of those illustrators who generate their own projects, create their own employment and work on their own terms.

I was invited (with Gary Powell. We had worked collaboratively previously as exhibitors) by Royal College of Art to be involved in a lecture & crit with RCA students which then developed into this international exhibition which we were invited to submit artwork for.

iii, 83 leaves : ill. ; 29 cm.