221 research outputs found
Contracts in Practice
Contracts are a form of lightweight formal specification embedded in the
program text. Being executable parts of the code, they encourage programmers to
devote proper attention to specifications, and help maintain consistency
between specification and implementation as the program evolves. The present
study investigates how contracts are used in the practice of software
development. Based on an extensive empirical analysis of 21 contract-equipped
Eiffel, C#, and Java projects totaling more than 260 million lines of code over
7700 revisions, it explores, among other questions: 1) which kinds of contract
elements (preconditions, postconditions, class invariants) are used more often;
2) how contracts evolve over time; 3) the relationship between implementation
changes and contract changes; and 4) the role of inheritance in the process. It
has found, among other results, that: the percentage of program elements that
include contracts is above 33% for most projects and tends to be stable over
time; there is no strong preference for a certain type of contract element;
contracts are quite stable compared to implementations; and inheritance does
not significantly affect qualitative trends of contract usage
Effect of RecA inactivation and detoxification systems on the evolution of ciprofloxacin resistance in Escherichia coli
Background
Suppression of SOS response and overproduction of reactive oxygen species (ROS) through detoxification system suppression enhance the activity of fluoroquinolones.
Objectives
To evaluate the role of both systems in the evolution of resistance to ciprofloxacin in an isogenic model of Escherichia coli.
Methods
Single-gene deletion mutants of E. coli BW25113 (wild-type) (ÎrecA, ÎkatG, ÎkatE, ÎsodA, ÎsodB), double-gene (ÎrecA-ÎkatG, ÎrecA-ÎkatE, ÎrecA-ÎsodA, ÎrecA-ÎsodB, ÎkatG-ÎkatE, ÎsodB-ÎsodA) and triple-gene (ÎrecA-ÎkatG-ÎkatE) mutants were included. The response to sudden high ciprofloxacin pressure was evaluated by mutant prevention concentration (MPC). The gradual antimicrobial pressure response was evaluated through experimental evolution and antibiotic resistance assays.
Results
For E. coli BW25113 strain, ÎkatE, ÎsodB and ÎsodB/ÎsodA mutants, MPC values were 0.25 mg/L. The ÎkatG, ÎsodA, ÎkatG/katE and ÎrecA mutants showed 2-fold reductions (0.125 mg/L). The ÎkatG/ÎrecA, ÎkatE/ÎrecA, ÎsodA/ÎrecA, ÎsodB/ÎrecA and ÎkatG/ÎkatE/ÎrecA strains showed 4â8-fold reductions (0.03â0.06 mg/L) relative to the wild-type. Gradual antimicrobial pressure increased growth capacity for ÎsodA and ÎsodB and ÎsodB/ÎsodA mutants (no growth in 4 mg/L) compared with the wild-type (no growth in the range of 0.5â2 mg/L). Accordingly, increased growth was observed with the mutants ÎrecA/ÎkatG (no growth in 2 mg/L), ÎrecA/ÎkatE (no growth in 2 mg/L), ÎrecA/ÎsodA (no growth in 0.06 mg/L), ÎrecA/ÎsodB (no growth in 0.25 mg/L) and ÎrecA/ÎkatG/ÎkatE (no growth in 0.5 mg/L) compared with ÎrecA (no growth in the range of 0.002â0.015 mg/L).
Conclusions
After RecA inactivation, gradual exposure to ciprofloxacin reduces the evolution of resistance. After suppression of RecA and detoxification systems, sudden high exposure to ciprofloxacin reduces the evolution of resistance in E. coli.Plan Nacional de I+D+i 2013-2016 and the Instituto de Salud Carlos III (projects and PI17/01501 and PI20-00239)SubdirecciĂłn General de Redes y Centros de InvestigaciĂłn Cooperativa, Ministerio de EconomĂa, Industria y Competitividad, Spanish Network for Research in Infectious Diseases (REIPI; RD16/0016/0001 and REIPI RD16/ 0016/0009
Till death (or an intruder) do us part: intrasexual-competition in a monogamous Primate
Polygynous animals are often highly dimorphic, and show large sex-differences in the degree of intra-sexual competition and aggression, which is associated with biased operational sex ratios (OSR). For socially monogamous, sexually monomorphic species, this relationship is less clear. Among mammals, pair-living has sometimes been assumed to imply equal OSR and low frequency, low intensity intra-sexual competition; even when high rates of intra-sexual competition and selection, in both sexes, have been theoretically predicted and described for various taxa. Owl monkeys are one of a few socially monogamous primates. Using long-term demographic and morphological data from 18 groups, we show that male and female owl monkeys experience intense intra-sexual competition and aggression from solitary floaters. Pair-mates are regularly replaced by intruding floaters (27 female and 23 male replacements in 149 group-years), with negative effects on the reproductive success of both partners. Individuals with only one partner during their life produced 25% more offspring per decade of tenure than those with two or more partners. The termination of the pair-bond is initiated by the floater, and sometimes has fatal consequences for the expelled adult. The existence of floaters and the sporadic, but intense aggression between them and residents suggest that it can be misleading to assume an equal OSR in socially monogamous species based solely on group composition. Instead, we suggest that sexual selection models must assume not equal, but flexible, context-specific, OSR in monogamous species.Wenner-Gren Foundation, L.S.B. Leakey Foundation, the National Geographic Society, National
Science Foundation (BCS- 0621020), the University of Pennsylvania Research Foundation and the Zoological Society of San Diego, German
Science Foundation (HU 1746-2/1
Electron impact ionization of 1-propanol
10 pags., 5 figs., 3 tabs.Experimental measurements of the cations created in electron impact ionization have been undertaken for the primary isomer of propanol using a Hidden Quadrupole Mass Spectrometer (EPIC 300), with a mass resolution of 1 amu. The mass spectra recorded at an incident electron energy of 70 eV reveals the relative probability of forming 50 different cations, by either direct ionization or dissociative ionization. Individual partial ionization cross sections (PICS) for 31 different cations were measured for the first time in this work, for the incident electron energy range from 10 to 100 eV. Also, appearance energies (AEs) and Wannier exponents for the 16 most intense cations formed in electron collisions with 1-propanol are reported. Where possible, those results are compared to those from an earlier investigation. Total Ionization Cross Sections (TICS) were also obtained from the sum of the measured PICS, for nearly all cations measured, and are compared to relevant data reported in the literature. In addition, as a part of this study, theoretical TICS were calculated using the Binary-encounter Bethe (BEB) and independent atom model with screening corrected additivity rule (IAMâSCAR) methods. Good agreement between current measured and calculated TICSs and corresponding earlier results was typically found.M.C.A.L. acknowledges financial support from Conselho Nacional de Desenvolvimento CientĂfico e TecnolĂłgico (CNPq),FundacĂŁo de Amparo Ă Pesquisa do Estado de Minas Gerais(FAPEMIG) and FINEP (under project CT-Infra), while M.J.B. thanks CNPq for his âSpecial Visiting Professorâ award. K.L.N. thanks CNPq for an âAttracting Young Talent Grantâ under the âScience WithoutBordersâ program. Some financial assistance from the Australian Research Council is also noted. Finally, S. Ghosh acknowledges forhis grant from PNPD/CAPES while G. Garcia thanks the Spanish Ministerio de Economia, Industria y Competitividad for his projectgrant FIS 2016 â80440 and the EU project FP7-ITN â ARGENT â608163.Peer Reviewe
Perinatal depression in the Spanish context: consensus report from the general council of psychology of Spain
Background: Perinatal depression is a major public health problem, with an estimated prevalence of approximately 15% during the first postpartum year. Despite the high prevalence of postpartum depression, there is no consensus regarding assessment and treatment in the Spanish context. The General Council of Psychology of Spain convened a working group of experts in the field, including both academics and healthcare professionals, to review and propose recommendations based on evidence and best practices that could be applied in the Spanish context. Method: A literature search was completed in various databases (e.g., Medline, PsychInfo) including a combination of terms related to peripartum depression (PPD) assessment and diagnosis, prevention, treatment, and cost-effectiveness. A narrative synthesis of the literature has been conducted together with a critical overview of PPD with a special focus on the Spanish context. Results: In this consensus report, developing questions including prevalence and assessment tools, comparative effectiveness of preventive and treatment interventions, and cost-effectiveness of PPD management have been analyzed. Conclusions: The General Council of Psychology of Spain network advocates the establishment of compulsory screening protocols in all the autonomous regions. Also, it is necessary to promote the inclusion in maternal education of programs for the promotion of mental well-being and selective/indicated prevention carried out by a psychology professional with specialized training in the area. This consensus document also promotes the presence of a psychology professional with specialized training in the area.
Antecedentes. La depresiĂłn perinatal es un importante problema de salud pĂșblica, con una prevalencia estimada de aproximadamente el 15% durante el primer año posparto. A pesar de la gran prevalencia de depresiĂłn posparto (DPP), no existe consenso sobre la evaluaciĂłn y el tratamiento en el contexto español. El Consejo General de PsicologĂa de España convocĂł a un grupo de trabajo de expertos en la materia, tanto acadĂ©micos como profesionales sanitarios, para revisar y proponer recomendaciones basadas en evidencias y mejores prĂĄcticas que puedan aplicarse en el contexto español. MĂ©todo. Se realizĂł una bĂșsqueda bibliogrĂĄfica en varias bases de datos (p. ej., Medline, PsychInfo) que incluĂa una combinaciĂłn de tĂ©rminos relacionados con la evaluaciĂłn y el diagnĂłstico de la DPP, prevenciĂłn, tratamiento y coste-eficacia. Se ha realizado una sĂntesis narrativa de la literatura junto con una visiĂłn crĂtica de la DPP con un enfoque especial en el contexto español. Resultados. Las preguntas de desarrollo que incluyen prevalencia y herramientas de evaluaciĂłn, la eficacia comparativa de las intervenciones preventivas y de tratamiento y la relaciĂłn coste-efectividad de la gestiĂłn de la PPD se han analizado en este informe de consenso. Conclusiones. La red del Consejo General de PsicologĂa de España aboga por el establecimiento de protocolos obligatorios de cribado en todas las Comunidades AutĂłnomas. Asimismo, es necesario promover la inclusiĂłn en la educaciĂłn materna de programas de promociĂłn del bienestar mental y la prevenciĂłn selectiva indicada llevadas a cabo por un profesional de la psicologĂa con formaciĂłn especializada en el ĂĄrea
FormulaciĂłn de producto con potencial agroindustrial a base de cidra Sechium edule (Jacq) Swartz
La AsociaciĂłn de Mujeres MultiĂ©tnicas(Asmufare) luego de un proceso de desplazamiento forzoso llegaron a habitar un territorio en la ciudad de Armenia, buscando reconstruir su cultura campesina. Actualmente cultivan y procesan cidra Sechium edule entre otros productos tradicionales. La cidra Sechium edule en Colombia es una materia prima con poco uso industrial y poco consumo domĂ©stico, a pesar de tener gran potencial nutricional y funcional debido al potencial de protecciĂłn de enfermedades; la cual puede ser empleada como materia prima para la formulaciĂłn de una galleta para personas con celiaquĂa. El objetivo de esta investigaciĂłn fue formular una galleta tipo colaciĂłn a base de cidra Sechium edule como alternativa de negocio para la asociaciĂłn de mujeres Asmufare, a partir de la caracterizaciĂłn y anĂĄlisis de mercado del producto. Se realizĂł la formulaciĂłn de la galleta, se caracterizĂł fĂsico-quĂmicamente teniendo en cuenta la normatividad y un anĂĄlisis de mercado del producto. Se logrĂł formular un producto de galleterĂa tipo colaciĂłn a base de harina y almidĂłn de cidra Sechium edule, con adiciĂłn de arroz Oryza sativa, para satisfacer las necesidades de la poblaciĂłn con celiaquĂa; el cual cumple con los estĂĄndares de clasificaciĂłn para este tipo de producto, siendo una alternativa para la poblaciĂłn fitness, donde se obtuvo una aceptaciĂłn del 87% de preferencia del consumidor potencial, con un posible precio de venta al pĂșblico de $1.544,63 que se ajusta a las expectativas de estos consumidores; logrando vincularse como potencial producto para su venta por parte de la asociaciĂłn Asmufare
Bevacizumab dose adjustment to improve clinical outcomes of glioblastoma.
Background
Glioblastoma (GBM) is one of the most aggressive and vascularized brain tumors in adults, with a median survival of 20.9âmonths. In newly diagnosed and recurrent GBM, bevacizumab demonstrated an increase in progression-free survival, but not in overall survival.
Methods
We conducted an in silico analysis of VEGF expression, in a cohort of 1082 glioma patients. Then, to determine whether appropriate bevacizumab dose adjustment could increase the anti-angiogenic response, we used in vitro and in vivo GBM models. Additionally, we analyzed VEGFA expression in tissue, serum, and plasma in a cohort of GBM patients before and during bevacizumab treatment.
Results
We identified that 20% of primary GBM did not express VEGFA suggesting that these patients would probably not respond to bevacizumab therapy as we proved in vitro and in vivo. We found that a specific dose of bevacizumab calculated based on VEGFA expression levels increases the response to treatment in cell culture and serum samples from mice bearing GBM tumors. Additionally, in a cohort of GBM patients, we observed a correlation of VEGFA levels in serum, but not in plasma, with bevacizumab treatment performance.
Conclusions
Our data suggest that bevacizumab dose adjustment could improve clinical outcomes in Glioblastoma treatment.post-print1360 K
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Rarity of monodominance in hyperdiverse Amazonian forests.
Tropical forests are known for their high diversity. Yet, forest patches do occur in the tropics where a single tree species is dominant. Such "monodominant" forests are known from all of the main tropical regions. For Amazonia, we sampled the occurrence of monodominance in a massive, basin-wide database of forest-inventory plots from the Amazon Tree Diversity Network (ATDN). Utilizing a simple defining metric of at least half of the treesââ„â10âcm diameter belonging to one species, we found only a few occurrences of monodominance in Amazonia, and the phenomenon was not significantly linked to previously hypothesized life history traits such wood density, seed mass, ectomycorrhizal associations, or Rhizobium nodulation. In our analysis, coppicing (the formation of sprouts at the base of the tree or on roots) was the only trait significantly linked to monodominance. While at specific locales coppicing or ectomycorrhizal associations may confer a considerable advantage to a tree species and lead to its monodominance, very few species have these traits. Mining of the ATDN dataset suggests that monodominance is quite rare in Amazonia, and may be linked primarily to edaphic factors
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