9,867 research outputs found
Buttons, Handles, and Keys: Advances in Continuous-Control Keyboard Instruments
This is the peer reviewed version of the following article: Buttons, Handles, and Keys: Advances in Continuous-Control Keyboard Instruments, which has been published in final form at http://dx.doi.org/10.1162/COMJ_a_00297. This article may be used for non-commercial purposes in accordance with MIT Press Journal's Terms and Conditions for Self-Archiving.
© 2015, MIT Press Journal
Staying in the science stream: patterns of participation in A-level science subjects in the UK.
This paper describes patterns of participation and attainment in A-level physics, chemistry and biology from 1961 to 2009. The A-level has long been seen as an important gateway qualification for higher level study, particularly in the sciences. This long term overview examines how recruitment to these three subjects has changed in the context of numerous policies and initiatives that seek to retain more young people in the sciences. The results show that recruitment to the pure sciences has stagnated, general trends have hardly varied and the track record of government policy in influencing change is not strong. There is no evidence for increasing achievement gaps between the sexes at A-level and even national policy requiring that all young people study science up to the age of 16 appears to have had little impact on recruitment at this leve
Prediction of stillbirth from maternal demographic and pregnancy characteristics
Objectives: To develop a model for prediction of stillbirth based on maternal characteristics and components of medical history and evaluate the performance of screening of this model for all stillbirths and those due to impaired placentation and unexplained causes.
Methods: This was a prospective screening study of 113,415 singleton pregnancies at 11+0-13+6 and 19+0-24+6 weeks’ gestation. The population included 113,019 live births and 396 (0.35%) antepartum stillbirths; 230 (58%) were secondary to impaired placentation and 166 (42%) were due to other or unexplained causes. Multivariate logistic regression analysis was used to determine the factors from maternal characteristics and medical history which provided a significant contribution to the prediction of stillbirth.
Results: The risk for stillbirth increased with maternal weight (OR 1.01 per kg after 69 kg), was higher in women of Afro-Caribbean race (OR 2.01), assisted conception (OR 1.79), cigarette smokers (OR 1.71), those with a history of chronic hypertension (OR 2.62), SLE/APS (OR 3.61) or diabetes mellitus (OR 2.55) and was increased in parous women with a history of previous stillbirth (OR 4.81). The model predicted 26% of unexplained stillbirths and 31% of those due to impaired placentation at FPR of 10%; within the impaired placentation group the DR of stillbirth at 37 weeks (38% vs 28%).
Conclusions: A model based on maternal characteristics and medical history recorded in early pregnancy can potentially predict one third of subsequent stillbirths. The extent to which such stillbirths could be prevented remains to be determined
Effect of transient pinning on stability of drops sitting on an inclined plane
We report on new instabilities of the quasi-static equilibrium of water drops
pinned by a hydrophobic inclined substrate. The contact line of a statically
pinned drop exhibits three transitions of partial depinning: depinning of the
advancing and receding parts of the contact line and depinning of the entire
contact line leading to the drop's translational motion. We find a region of
parameters where the classical Macdougall-Ockrent-Frenkel approach fails to
estimate the critical volume of the statically pinned inclined drop
Variation in ampicillin dosing for lower respiratory tract infections and neonatal bacterial infections in US children\u27s hospitals
OBJECTIVE: We examined ampicillin dosing in pediatric patients across 3 conditions: (1) bacterial lower respiratory tract infections (LRTIs) in infants and children \u3e3 months, (2) neonates with suspected or proven sepsis, and (3) neonates with suspected central nervous system (CNS) infections. We compared our findings to dosing guidance for these specific indications.
DESIGN: Retrospective cohort study.
SETTING: The study included data from 32 children\u27s hospitals in the United States.
METHODS: We reviewed prescriptions from the SHARPS study of antimicrobials, a survey of antibiotic prescribing from July 2016 to December 2017. Prescriptions were analyzed for indication, total daily dose per kilogram, and presence of antimicrobial stewardship program (ASP) review. LRTI prescriptions were compared to IDSA recommendations for community-acquired pneumonia. Neonatal prescriptions were compared to recommendations from the American Academy of Pediatrics (AAP). Prescriptions were categorized as optimal (80%-120% of recommended dosing), suboptimal (\u3c80% of recommended dosing), or excessive (\u3e120% of recommended dosing).
RESULTS: Among 1,038 ampicillin prescriptions, we analyzed 88 prescriptions for LRTI, 499 prescriptions for neonatal sepsis, and 27 prescriptions for neonatal CNS infection. Of the LRTI prescriptions, 77.3%were optimal. Of prescriptions for neonatal sepsis, 81.6% were excessive compared to AAP bacteremia recommendations but 78.8% were suboptimal compared to AAP meningitis guidelines. Also, 48.1% of prescriptions for neonatal CNS infection were suboptimal, and 50.6% of prescriptions were not reviewed by the ASP.
CONCLUSIONS: LRTI dosing is generally within the IDSA-recommended range. However, dosing for neonatal sepsis often exceeds the recommendation for bacteremia but is below the recommendation for meningitis. This variability points to an important opportunity for future antimicrobial stewardship efforts
Inhibition of protein crystallization by evolutionary negative design
In this perspective we address the question: why are proteins seemingly so
hard to crystallize? We suggest that this is because of evolutionary negative
design, i.e. proteins have evolved not to crystallize, because crystallization,
as with any type of protein aggregation, compromises the viability of the cell.
There is much evidence in the literature that supports this hypothesis,
including the effect of mutations on the crystallizability of a protein, the
correlations found in the properties of crystal contacts in bioinformatics
databases, and the positive use of protein crystallization by bacteria and
viruses.Comment: 5 page
Protein crystallization as a process step in a novel meso oscillatory flow reactor: study of lysozyme phase behavior
In the present work, it is reported for the first time the study of the applicability of a novel meso oscillatory flow reactor (meso-OFR) for protein crystallization as a process step. Crystallization assays carried out in the designed device enabled to derive a two-dimensional lysozyme phase diagram (lysozyme concentration against sodium chloride concentration). Results evidence the formation of several types of crystals (different size and shape), with a strong influence of salt concentration on crystal shape. Results also show that lysozyme remains active at the end of the experiments. Furthermore, it was possible to verify the reduction of the metastability zone when compared to lysozyme crystallization conducted under quiescent conditions. Induction times were also measured by online monitoring of the turbidity of the crystallization solution, obtained values being between 41 and 900 minutes. Beyond providing improved understanding of protein phase behavior under oscillatory flow mixing, the results are very promising regarding the feasibility of the designed methodology for protein crystallization as a process step.This work was financially supported by the European Regional Development Fund (FEDER) through COMPETE 2020-Operational Programme Competitiveness and Internationalization (POCI) (UID/EQU/00511/2013-LEPABE-Laboratory for Process Engineering, Environment, Biotechnology and Energy-EQU/00511; POCI-01-0145-FEDER-006684) and by national funds through FCT-Portuguese Foundation for Science and Technology-under the projects: UID/BIO/04469/2013; IF exploratory project [IF/01087/2014]; postdoctoral Fellowship [SFRH/BPD/96132/2013]. A. Ferreira is an Investigator FCT (IF/01087/2014)
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