1,458 research outputs found
Selection of chromosomal DNA libraries using a multiplex CRISPR system.
The directed evolution of biomolecules to improve or change their activity is central to many engineering and synthetic biology efforts. However, selecting improved variants from gene libraries in living cells requires plasmid expression systems that suffer from variable copy number effects, or the use of complex marker-dependent chromosomal integration strategies. We developed quantitative gene assembly and DNA library insertion into the Saccharomyces cerevisiae genome by optimizing an efficient single-step and marker-free genome editing system using CRISPR-Cas9. With this Multiplex CRISPR (CRISPRm) system, we selected an improved cellobiose utilization pathway in diploid yeast in a single round of mutagenesis and selection, which increased cellobiose fermentation rates by over 10-fold. Mutations recovered in the best cellodextrin transporters reveal synergy between substrate binding and transporter dynamics, and demonstrate the power of CRISPRm to accelerate selection experiments and discoveries of the molecular determinants that enhance biomolecule function
The Influence of Education Personnel Competency on Student Academic Service Satisfaction
This research aims to determine the extent to which the quality of educators and the quality of educational staff influence student satisfaction with the services they receive at an educational institution. The research method used is a quantitative research approach. The survey and research subjects included 85 education staff and 278 Indonesian Business and Computer Institute students who were randomly selected from the Indonesian Business and Computer Institute. Data was collected through a questionnaire using a Likert scale. To ensure the reliability of the data, validity and reliability tests were carried out, and the results showed that all data followed a normal distribution. The research results reveal that the quality of educators has a significant influence on the level of student satisfaction with the services they receive. Besides that, The quality of educational staff also has a significant influence on the level of student satisfaction with these services. These results confirm that both the quality of educators and the quality of educational staff play an essential role in shaping student perceptions and satisfaction with the services provided by educational institutions. Furthermore, this study also measured the coefficient of determination (R)2, which revealed that the quality of educators and educational staff strongly correlates with student satisfaction with services. In other words, these variables can explain most of the variation in student satisfaction levels. These results highlight the importance of the quality of educators and education personnel in creating an adequate and satisfying educational environment for students
Mapping load transfer from the plantar surface of the foot to the walls of the total contact cast (TCC)
Experimentation of an adaptive and autonomous RF signalling strategy for detection
In this paper we discuss a straightforward signalling strategy for target detection and shared spectrum usage. We further combine additional practical concerns such as waveform modulus and extended target matched illumination to improve detection performance in dynamic interference environments. The impetus for the straightforward, yet suboptimal, strategy are the low cost drivers for small sensing platforms, such as small unmanned aerial systems (SUAS). Herein, we discuss a complete strategy and algorithm for sensing the environment, interrogating the target response and adapting the transmitted waveform to avoid the primary users while putting more energy on target than previous non-adaptive strategies. We give simulation results and initial experimental results to corroborate the theoretical and simulated findings
A novel isolator-based system promotes viability of human embryos during laboratory processing
In vitro fertilisation (IVF) and related technologies are arguably the most challenging of all cell culture applications. The starting material is a single cell from which one aims to produce an embryo capable of establishing a pregnancy eventually leading to a live birth. Laboratory processing during IVF treatment requires open manipulations of gametes and embryos, which typically involves exposure to ambient conditions. To reduce the risk of cellular stress, we have developed a totally enclosed system of interlinked isolator-based workstations designed to maintain oocytes and embryos in a physiological environment throughout the IVF process. Comparison of clinical and laboratory data before and after the introduction of the new system revealed that significantly more embryos developed to the blastocyst stage in the enclosed isolator-based system compared with conventional open-fronted laminar flow hoods. Moreover, blastocysts produced in the isolator-based system contained significantly more cells and their development was accelerated. Consistent with this, the introduction of the enclosed system was accompanied by a significant increase in the clinical pregnancy rate and in the proportion of embryos implanting following transfer to the uterus. The data indicate that protection from ambient conditions promotes improved development of human embryos. Importantly, we found that it was entirely feasible to conduct all IVF-related procedures in the isolator-based workstations
Identifying metabolites by integrating metabolome databases with mass spectrometry cheminformatics.
Novel metabolites distinct from canonical pathways can be identified through the integration of three cheminformatics tools: BinVestigate, which queries the BinBase gas chromatography-mass spectrometry (GC-MS) metabolome database to match unknowns with biological metadata across over 110,000 samples; MS-DIAL 2.0, a software tool for chromatographic deconvolution of high-resolution GC-MS or liquid chromatography-mass spectrometry (LC-MS); and MS-FINDER 2.0, a structure-elucidation program that uses a combination of 14 metabolome databases in addition to an enzyme promiscuity library. We showcase our workflow by annotating N-methyl-uridine monophosphate (UMP), lysomonogalactosyl-monopalmitin, N-methylalanine, and two propofol derivatives
Fast interior point solution of quadratic programming problems arising from PDE-constrained optimization
Interior point methods provide an attractive class of approaches for solving linear, quadratic and nonlinear programming problems, due to their excellent efficiency and wide applicability. In this paper, we consider PDE-constrained optimization problems with bound constraints on the state and control variables, and their representation on the discrete level as quadratic programming problems. To tackle complex problems and achieve high accuracy in the solution, one is required to solve matrix systems of huge scale resulting from Newton iteration, and hence fast and robust methods for these systems are required. We present preconditioned iterative techniques for solving a number of these problems using Krylov subspace methods, considering in what circumstances one may predict rapid convergence of the solvers in theory, as well as the solutions observed from practical computations
Recent Southern Ocean warming and freshening driven by greenhouse gas emissions and ozone depletion
Recommended age groups and frequency of mammography screening : a systematic review
Esta revisão teve por objetivo avaliar a
força de evidência do atual indicador de desempenho
português relativo ao rastreio do Câncer da
Mama através da mamografia, de modo a determinar
o grupo etário e a periodicidade recomendadas.
Foram pesquisados artigos nas principais
bases de dados internacionais de literatura médica.
Incluímos artigos publicados entre Janeiro de
2006 e Janeiro de 2012 que correspondiam aos
objetivos da revisão. Foi utilizada a taxonomia
SORT para a classificação dos resultados. Dos 253
artigos encontrados foram selecionados cinco que
cumpriam os critérios de inclusão. Estes incluem
três revisões sistemáticas (RS), uma meta-análise
(MA) e uma norma de orientação clínica (NOC)
baseada numa RS. Os artigos selecionados avaliaram
a redução da mortalidade por câncer da
mama através do rastreio com mamografia. A realização
do rastreio mamográfico entre os 50 e os
69 anos é recomendado em todos os artigos que
avaliam esta faixa etária. A NOC recomenda o
rastreio bienal. Em suma, a mamografia deverá
ser realizada entre os 50 e os 69 anos com uma
periodicidade bienal. Estes resultados vão ao encontro
do atual indicador de desempenho do rastreio
do câncer da mama em Portugal.The scope of this review was to assess the strength of evidence for the current Portuguese performance indicator on breast cancer screening with mammography in order to determine the recommended age group and periodicity for screening. A search for articles was conducted in the main international databases of medical literature. Articles published between January 2006 and January 2012 addressing the objectives of this review were included. The SORT taxonomy was used to classify the results. Of the 253 articles, five articles met the inclusion criteria and were selected for review. These included three systematic reviews, one meta-analysis and one clinical guideline based on a systematic review. A reduction in breast cancer mortality with mamography screening was the outcome in all articles selected. Mammography screening between 50 and 69 years was recommended in all articles that assess this age group. The clinical guidelines recommended screening every two years. In conclusion, the current literature recommends mammography for women every two years between the ages of 50 and 69 years. This is consistent with the current performance indicator for breast cancer screening in Portugal
Language and social/emotional problems identified at a universal developmental assessment at 30 months
Non peer reviewedPublisher PD
- …