153 research outputs found
Modeling Flocks and Prices: Jumping Particles with an Attractive Interaction
We introduce and investigate a new model of a finite number of particles
jumping forward on the real line. The jump lengths are independent of
everything, but the jump rate of each particle depends on the relative position
of the particle compared to the center of mass of the system. The rates are
higher for those left behind, and lower for those ahead of the center of mass,
providing an attractive interaction keeping the particles together. We prove
that in the fluid limit, as the number of particles goes to infinity, the
evolution of the system is described by a mean field equation that exhibits
traveling wave solutions. A connection to extreme value statistics is also
provided.Comment: 35 pages, 9 figures. A shortened version appears as arXiv:1108.243
Maternal Genetic Mutations as Gestational and Early Life Influences in Producing Psychiatric Disease-Like Phenotypes in Mice
Risk factors for psychiatric disorders have traditionally been classified as genetic or environmental. Risk (candidate) genes, although typically possessing small effects, represent a clear starting point to elucidate downstream cellular/molecular pathways of disease. Environmental effects, especially during development, can also lead to altered behavior and increased risk for disease. An important environmental factor is the mother, demonstrated by the negative effects elicited by maternal gestational stress and altered maternal care. These maternal effects can also have a genetic basis (e.g., maternal genetic variability and mutations). The focus of this review is “maternal genotype effects” that influence the emotional development of the offspring resulting in life-long psychiatric disease-like phenotypes. We have recently found that genetic inactivation of the serotonin 1A receptor (5-HT1AR) and the fmr1 gene (encoding the fragile X mental retardation protein) in mouse dams results in psychiatric disease-like phenotypes in their genetically unaffected offspring. 5-HT1AR deficiency in dams results in anxiety and increased stress responsiveness in their offspring. Offspring of 5-HT1AR deficient dams display altered development of the hippocampus, which could be linked to their anxiety-like phenotype. Maternal inactivation of fmr1, like its inactivation in the offspring, results in a hyperactivity-like condition and is associated with receptor alterations in the striatum. These data indicate a high sensitivity of the offspring to maternal mutations and suggest that maternal genotype effects can increase the impact of genetic risk factors in a population by increasing the risk of the genetically normal offspring as well as by enhancing the effects of offspring mutations
Effectiveness of different trap design in mass trapping of Bothynoderes punctiventris Germar
The discovery of an aggregation attractant for Bothynoderes punctiventris Germ. raised several questions for possible improvements of IPM of Bothynoderes punctiventris in sugar beet. First results on exploration of possibilities for its use for monitoring purposes as well as for mass trapping of adults of the pest are described in this paper. Trap design effectiveness was evaluated in the overwintering fields of sugar beet weevil for two years in localities in Serbia and Hungary. Among trap designs tested it was proved that baited CSALOMON® TAL trap design was optimal
Pregnancy Outcome Following Pelvic Infection
To determine whether a previous pelvic infection has an effect on the outcome of a subsequent
pregnancy, we identified women with a diagnosis of pelvic inflammatory disease (PID), amnionitis,
and postpartum or postabortal endometritis-salpingitis by a retrospective chart review of all patients
admitted to the Department of Obstetrics and Gynecology at The New York Hospital-Cornell
Medical Center between 1975 and 1977 and between 1985 and 1988. Antimicrobial regimens
effective against Chlamydia trachomatis were initiated in 1985. Controls were randomly selected
patients presenting during the same time period for routine examinations who had normal Pap
smears and no infections. Both groups were comparable for age, race, gravity, and parity. Differences
were evaluated by chi square analysis, using the Yates correction factor. We identified 183
women with a history of the above infections who subsequently conceived, and 82 controls. There
were no differences in outcome between the two index groups. Term vaginal deliveries occurred in
14.2% of the women with a prior pelvic infection and in 56% of the controls (P < 0.001). Among the
97 women who had had PID, 21 (21.6%) had a spontaneous abortion in the subsequent pregnancy,
as opposed to 6 (7.3%) of the controls (P = 0.013). In addition, eight of the women with PID (but no
controls) went into preterm labor (P = 0.021). An increased incidence of preterm labor (P = 0.001)
was also observed in women with a history of amnionitis. A history of endometritis was not
associated with an increased prevalence of abnormal outcome in subsequent pregnancies. PID and
amnionitis may adversely affect the outcome of subsequent pregnancies
The common truncation variant in pancreatic lipase related protein 2 (PNLIPRP2) is expressed poorly and does not alter risk for chronic pancreatitis
A nonsense variant (p.W358X) of human pancreatic lipase related protein 2 (PNLIPRP2) is present in different ethnic populations with a high allele frequency. In cell culture experiments, the truncated protein mainly accumulates inside the cells and causes endoplasmic reticulum stress. Here, we tested the hypothesis that variant p.W358X might increase risk for chronic pancreatitis through acinar cell stress. We sequenced exon 11 of PNLIPRP2 in a cohort of 256 subjects with chronic pancreatitis (152 alcoholic and 104 non-alcoholic) and 200 controls of Hungarian origin. We observed no significant difference in the distribution of the truncation variant between patients and controls. We analyzed mRNA expression in human pancreatic cDNA samples and found the variant allele markedly reduced. We conclude that the p.W358X truncation variant of PNLIPRP2 is expressed poorly and has no significant effect on the risk of chronic pancreatitis
THE EFFECT OF DAILY PHYSICAL EDUCATION LESSONS ON HUNGARIAN STUDENT'S PHYSICAL ACTIVITY LEVELS AND BODY COMPOSITION
Lifestyle, physical activity level and nutritional habits as well as environmental factors are having a greater and greater detrimental effect on the health of various populations. In the present study we systematically researched the physical status of schoolchildren. It is well known that as children grow up, the amount of spontaneous physical activity they perform decreases as they have more mental tasks to do these negative factors can be offset with daily physical education. We measured children participating in physical education on a daily basis, consisting of 5th (10-11 years old) and 9th (14-15 years old) grade students and control groups of 4th (9-10 years old) and 8th (13-14 years old) grade students, respectively, for a total of 196 persons (94 girls and 102 boys). Habitual physical activity was obtained with Actigraph, (GT1M/GT3X) and body fat percentage was calculated from anthropometrical measurements. As expected, we were able to observe a linear correlation between the physical activity levels and the body composition of the participants. The more time the subjects spent performing MVPA (Moderate and Vigorous Physical Activity), the less body fat they had. The recommended MVPA is a minimum of one hour per day, but these Hungarian children had two hours of MPVA per day. Our results lead us to conclude that ninety minutes of additional physical education per week for 7-8 months cannot be considered sufficient for a full impact analysis nor for schoolchildren’s physical activity needs or body composition, though an increase in the amount of time spent in physical education classes shows beneficial effects for these children
THE EFFECT OF DAILY PHYSICAL EDUCATION LESSONS ON HUNGARIAN STUDENT'S PHYSICAL ACTIVITY LEVELS AND BODY COMPOSITION
Lifestyle, physical activity level and nutritional habits as well as environmental factors are having a greater and greater detrimental effect on the health of various populations. In the present study we systematically researched the physical status of schoolchildren. It is well known that as children grow up, the amount of spontaneous physical activity they perform decreases as they have more mental tasks to do these negative factors can be offset with daily physical education. We measured children participating in physical education on a daily basis, consisting of 5th (10-11 years old) and 9th (14-15 years old) grade students and control groups of 4th (9-10 years old) and 8th (13-14 years old) grade students, respectively, for a total of 196 persons (94 girls and 102 boys). Habitual physical activity was obtained with Actigraph, (GT1M/GT3X) and body fat percentage was calculated from anthropometrical measurements. As expected, we were able to observe a linear correlation between the physical activity levels and the body composition of the participants. The more time the subjects spent performing MVPA (Moderate and Vigorous Physical Activity), the less body fat they had. The recommended MVPA is a minimum of one hour per day, but these Hungarian children had two hours of MPVA per day. Our results lead us to conclude that ninety minutes of additional physical education per week for 7-8 months cannot be considered sufficient for a full impact analysis nor for schoolchildren’s physical activity needs or body composition, though an increase in the amount of time spent in physical education classes shows beneficial effects for these children
SURFACE TREATMENT AND EXAMINATION OF GRADE 2 AND GRADE 5 TITANIUM
Surface characteristics play an important role in the implant-bone integration that is required for the long-term reliability of dental and orthopedic implants. In this paper, we investigate the effect of acid etching on the mass reduction and roughness of grade 2 and grade 5 Ti under controlled experimental conditions. Three different etching compounds were investigated: 30% HCl, 85% H3PO4 and the compound of 30% (COOH)2 × 2H2O and 30% H2O2 in various treatment intervals under controlled temperature. Stereo microscopy, scanning electron microscopy, roughness and weight measurements were carried out on the samples. We found that neither 85% H3PO4 nor the compound of 30% (COOH)2 × 2H2O and 30% H2O2 were able to remove the machining marks from the surface of Ti discs in our experimental setting. On the other hand, etching in 30% HCl yielded even surfaces both on Ti grade 2 and 5 discs. We also found that etching at higher temperatures in 30% HCl resulted in significant mass loss
SURFACE TREATMENT AND EXAMINATION OF GRADE 2 AND GRADE 5 TITANIUM
Surface characteristics play an important role in the implant-bone integration that is required for the long-term reliability of dental and orthopedic implants. In this paper, we investigate the effect of acid etching on the mass reduction and roughness of grade 2 and grade 5 Ti under controlled experimental conditions. Three different etching compounds were investigated: 30% HCl, 85% H3PO4 and the compound of 30% (COOH)2 × 2H2O and 30% H2O2 in various treatment intervals under controlled temperature. Stereo microscopy, scanning electron microscopy, roughness and weight measurements were carried out on the samples. We found that neither 85% H3PO4 nor the compound of 30% (COOH)2 × 2H2O and 30% H2O2 were able to remove the machining marks from the surface of Ti discs in our experimental setting. On the other hand, etching in 30% HCl yielded even surfaces both on Ti grade 2 and 5 discs. We also found that etching at higher temperatures in 30% HCl resulted in significant mass loss
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