Search results for "Negative"

Estimation Of The Genetic Parameters Of Eight Soybean Varieties In The Wasegi Village At Prafi District Manokwari Regency

2020

This study aims to estimate genetic parameters including genetic diversity coefficient, phenotypic diversity coefficient, heritability value, and the correlation between the character of plants from eight soybean varieties. The research was conducted from August to December 2017, in the Wasafi Village of Prafi District, Manokwari Regency. The study was designed using Randomized Block Design (RBD) with 8 treatments of soybean varieties. Each treatment was repeated 4 times, to obtain 32 experimental units. The data obtained were analyzed using ANOVA and if it had a significant effect, it was further tested using the Duncan Multiple Range Test (DMRT) at the 95% level, through the Costat progra…

2006

Understanding evolutionary processes that drive genome reduction requires determining the tempo (rate) and the mode (size and types of deletions) of gene losses. In this study, we analysed five endosymbiotic genome sequences of the gamma-proteobacteria (three different Buchnera aphidicola strains, Wigglesworthia glossinidia, Blochmannia floridanus) to test if gene loss could be driven by the selective importance of genes. We used a parsimony method to reconstruct a minimal ancestral genome of insect endosymbionts and quantified gene loss along the branches of the phylogenetic tree. To evaluate the selective or functional importance of genes, we used a parameter that measures the level of ad…

Amplified fragment length polymorphism (AFLP) and biochemical typing of Photobacterium damselae subsp. damselae.

2002

Aims: The aim of the present study was to characterize subspecifically Photobacterium damselae subsp. damselae strains isolated from cultured Sparus aurata and Dicentrarchus labrax by means of phenotypic and molecular typing techniques (amplified fragment length polymorphism, AFLP). Methods and Results: Seventy-one strains of P. damselae subsp. damselae were isolated from 38 cultured fishes at different fish farms located on the Mediterranean coast near Valencia, Spain. Most fish studied were asymptomatic and some were recovered during infectious outbreaks. Phenotypic characterization revealed a considerable degree of variability within the subspecies, including some characters, such as pro…

EFFECT OF DELETERIOUS MUTATION-ACCUMULATION ON THE FITNESS OF RNA BACTERIOPHAGE MS2

2000

RNA viruses show the highest mutation rate in nature. It has been extensively demonstrated that, in the absence of purifying selection, RNA viruses accumulate deleterious mutations at a high rate. However, the parameters describing this accumulation are, in general, poorly understood. The present study reports evidences for fitness declines by the accumulation of deleterious mutations in the bacteriophage MS2. We estimated the rate of fitness decline to be as high as 16% per bottleneck transfer. In addition, our results agree with an additive model of fitness effects.

Some notes on the geographical distribution of the human red cell acid phosphatase phenotypes

1972

Basing on the data of 65 populations the geographical variability of the human red cell acid phosphatase phenotypes resp. alleles was studied. We found a marked distribution gradient: The frequency of pB-alleles increases with the increase of the mean annual temperature of the various biotops, whereas the pA-allele frequencies show a clear decrease. For this allele we calculated a significant negative correlation between its frequency and the mean annual temperature: r=-0.71; P<0.001. We suppose that the pB-allele is in some way adaptive under the climatic conditions of tropical biotops. The possible reasons are discussed.

New Vocabulary for Bacterial Communication

2019

Abstract Quorum sensing (QS) is widely accepted as a procedure that bacteria use to converse. However, prevailing thinking places acyl homoserine lactones (AHLs) at the forefront of this communication pathway in Gram‐negative bacteria. With the advent of high‐throughput genomics and the subsequent influx of bacterial genomes, bioinformatics analysis has determined that the genes encoding AHL biosynthesis, originally discovered to be indispensable for QS (LuxI‐like proteins and homologues), are often absent in QS‐capable bacteria. Instead, the sensing protein (LuxR‐like proteins) is present with an apparent inability to produce any outgoing AHL signal. Recently, several signals for these Lux…

Acogimiento en familia extensa: perfil psicosocial de las familias y de los menores acogidos

2021

[EN] Extended family foster care family is the most frequent protective measure for minors in Spain. The objectives of the present study are to analyze the family profile according to different dimensions, knowing the state of psychosocial health care of minors in foster care and study the relationship between family and minor variables. The sample consisted of 101 families and 121 minors between 6 and 17 years old (M = 10.07; DT = 3.92), living in the province of Valencia. The evaluation was carried out through individual interviews with every family. Results show good functionality of families taking into account the family climate, the level of stress, the educational styles and the supp…

The Food4toddlers study - study protocol for a web-based intervention to promote healthy diets for toddlers: a randomized controlled trial

2019

Abstract Background Eating habits are established during childhood and track into adolescence and later in life. Given that these habits have a large public health impact and influence the increasing rates of childhood obesity worldwide, there is a need for effective, evidence-based prevention trials promoting healthy eating habits in the first 2 years of life. The aim of this study was to develop and evaluate the effect of an eHealth intervention called Food4toddlers, aiming to promote healthy dietary habits in toddlers by targeting parents’ awareness of their child’s food environment (i.e., how food is provided or presented) and eating environment (e.g., feeding practices and social inter…

Editorial Commentary on “The role of periodontal microorganisms in the pathogenesis of myocardial infarction. From PCR techniques to microbiome seque…

2021

The effects of small-scale disturbance on forest birds: a meta-analysis

2010

Small-scale disturbance is a significant process in all major forest biomes. Some silvicultural practices, particularly group selection harvesting, intend to emulate natural small-scale disturbance by harvesting small clearcuts in the continuous forest. We conducted a meta-analysis on the effects of small-scale harvesting on North American breeding forest birds. We extracted species richness and relative abundance of several functional bird groups and guilds from published studies and compared them between gap-dominated and unlogged forest as a function of forest type and the size and age of the gap. The abundance of many bird groups was higher in the gap-dominated than in the continuous f…