Dynamics in a three-generational family: Teens, grandparents, and babies.

A sample of 64 2-grandparent, working-class families with a teen and her child under 2 yrs was used to test the hypothesis that grandmothers have a direct influence on their grandchild and that grandparents also have an indirect effect on the young child through their influence on the teen's nurturance and perceptions of family support. Hypotheses were based on research concerning fathers, the authors' previous research showing direct grandfather effects, and the literature on modeling, mediation, and surrogate parenting. Major findings from the path analyses were that grandfathers had a direct effect on children and that grandmothers had neither direct nor indirect influence. Results are discussed in terms of the salience of nurturant grandfathers in these families and the unique role they may play in the family. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The effects of age and gender on perceived facial attractiveness: A reply to McLellan and McKelvie.

Comments on B. McLellan and S. J. McKelvie's study (see record 1993-45212-001) investigating the effects of age and gender on attractiveness of photographs of faces. The results of this study are challenged in the context of sociobiological theory for the following reasons: (1) the implicit assumption that facial attractiveness can be used as an indicator of human mate choice is questionable; (2) age categories of Ss choosing photographs of faces were too broad to test the validity of a sociobiological hypothesis; and (3) results were not accurately interpreted. (French abstract) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Adaptive Exponentially Weighted Moving Average Schemes Using a Kalrnan Filter

Two adaptive exponentially weighted moving average control schemes are proposed. The weighting coefficient is updated using a Kalman filter algorithm. The two test statistics incorporate an integral error term. Simulated average run lengths indicate the proposed schemes are sensitive to small process shifts, but do tend to ring false alarms when there is no process change. For medium and large process changes and trends their performance is comparable to that, of Lucas's combined Shewhart-CUSUM control scheme. Some application of the proposed schemes to correlated data indicate robust performance. Conclusions are drawn that the Kalman filter used to model a process together with a detection mechanism applied to the residuals closely resembles the work done in control theory.     

Study of cellular architecture and micromechanical properties of cuajilote fruits (Parmentiera edulis D.C.) using different microscopy techniques

The cuajilote (Parmentiera edulis D.C.) tree produces fibrous fruits with a high content of lignocellulosic compounds. However, this fruit and their fibers have been scarcely studied. For this reason, an integral study of their cellular architecture, physicochemical, micromechanical, and structural properties in two maturity stages were carried out. Physicochemical tests, light, confocal and electron microscopy, microindentation, and X‐ray diffraction were used for the characterization of fruit and their fibers. Chemical analysis showed that the unripe fruits have the highest cellulose content (42.17%), but in ripe fruit the cellulose content decreases (32.76%) while lignin content increases from 35.26 to 40.79%, caused by the lignification of the sclerenchyma fibers. Microstructural and micromechanical studies in the different regions of the fruit provided relevant information about its cellular architecture, distribution of lignocellulosic compounds and its role in the micromechanical properties of their fibers. The thickening cell wall of sclerenchyma fibers was caused by the cellular lignification of the ripe fruits. According to the physicochemical and structural studies, cuajilote fibers are comparable to other fibers obtained from crops rich in lignocellulosic compounds. The current study provided new knowledge about the cellular architecture of fruit and criteria for selecting the ripening stage adequate for the extraction of cellulose or lignin. Furthermore, information regarding the micromechanical properties of their fibers and which structural arrangement could be more convenient for mechanical reinforcement of biodegradable materials was obtained.     

Extracts of edible and medicinal plants in inhibition of growth, adherence, and cytotoxin production of Campylobacter jejuni and Campylobacter coli

Abstract: Campylobacter spp. is recognized as one of the most common cause of food‐borne bacterial gastroenteritis in humans. Campylobacter infection causes campylobacteriosis, which can range from asymptomatic to dysentery‐type illnesses with severe complications, such as Guillian‐Barre syndrome. Epidemiological studies have revealed that consumption of poultry products is an important risk factor of this disease. Adherence and cytotoxic activity of the bacteria to host mucosal surfaces have been proposed to be critical steps in pathogenesis. Innovative tools for controlling Campylobacter, such as natural products from plants, represent good alternatives for use in foods or as therapeutic agents. In this study, 28 edible or medicinal plants species were analyzed for their bactericidal effects on the growth of Campylobacter jejuni and C. coli. The extracts of Acacia farnesiana, Artemisia ludoviciana, Opuntia ficus‐indica, and Cynara scolymus were the most effective against these microorganisms at minimal bactericidal concentrations (MBCs) of 0.3, 0.5, 0.4, and 2.0 mg/mL, respectively. No effect on growth was detected with lower concentrations of extract (25%, 50%, or 75% of the MBC) added to the media. The effect of each extract (75% of the MBC) on adherence and cytotoxicity of C. jejuni and C. coli was evaluated in Vero cells. Adherence of Campylobacter to Vero cells was significantly affected by all the extracts. Cytotoxic activity of bacterial cultures was inhibited by A. farnesiana and A. ludoviciana. These plant extracts are potential candidates to be studied for controlling Campylobacter contamination in foods and the diseases associated with this microorganism. Practical Application: Innovative tools for controlling Campylobacter, such as natural products from plants, represent good alternatives for use in foods or as therapeutic agents. The extracts of Acacia farnesiana, Artemisia ludoviciana, Opuntia ficus‐indica, and Cynara scolymus were the most effective against these microorganisms. Adherence and cytotoxic activity of the bacteria to host mucosal surfaces which are critical steps in pathogenesis were decreased by these extracts. Our results point to these plants as potential candidates for the control of Campylobacter contamination in foods, the treatment of the diseases associated with this microorganism, and as feed supplements to reduce on‐farm prevalence of Campylobacter.     

Feasibility, cost, and cost-effectiveness of a telephone-based motivational intervention for underserved pregnant smokers.

This study reports on the evaluation of the feasibility, cost, and cost-effectiveness of a proactively provided telephone-based motivational smoking cessation intervention to an underserved population of pregnant smokers who may or may not receive ongoing prenatal care. As part of the New England SCRIPT randomized clinical trial comparing the efficacy of three types of smoking cessation interventions for pregnant smokers, one-third of the women (n = 358) received a motivational telephone counseling intervention (MI) delivered by trained counselors using a semistructured protocol. Although this population was very mobile, the MI counselors were able to reach 86% of the women with at least one call and 46% received all three calls. The group receiving three MI calls had a cotinine-confirmed quit rate of 23%. Cost-effectiveness analyses for those women receiving telephone counseling supported the net benefit in favor of the three phone calls compared with the women who did not receive any telephone calls, with an effectiveness to cost ratio of 1:US dollars 84. Our results suggest that telephone-based motivational smoking cessation counseling may be a feasible and cost-effective method for low-income pregnant smokers enrolled in prenatal care.     

Effects of gamma irradiation on the viability and phenotypic characteristics of Salmonella Enteritidis inoculated into specific-pathogen-free eggs

The goal of this study was to determine the effects of various levels of gamma irradiation on the phenotypic characteristics of 20 strains of Salmonella Enteritidis inoculated separately into specific-pathogen-free shell eggs. Bacterial strains were inoculated into egg yolks and exposed to (60)Co radiation at doses of 0.49 to 5.0 kGy. The eggs were maintained at 25°C and analyzed for the presence of Salmonella on days 1, 2, 4, and 7, and the recovered Salmonella isolates were characterized biochemically. All strains were resistant to doses of 0.49, 0.54, 0.59, 0.8, and 1 kGy; colony counts were ≥10(5) CFU/ml of egg yolk except for one strain, which was detected at 96 h and at 7 days after irradiation at 1 kGy, with a population reduction of 2 log CFU/ml. For the other evaluated doses, 12 strains (60.0%) were resistant at 1.5 kGy and 7 strains (35.0%) were resistant at 3.0 kGy. Among all analyzed strains, 5.0 kGy was more effective for reducing and/or eliminating the inoculated bacteria; only two (10%) strains were resistant to this level of irradiation. Salmonella colony counts were significantly reduced (P < 0.01) with increasing doses from the day 1 to 7 of observation, when microbial growth peaked. Loss of mobility, lactose fermentation, citrate utilization, and hydrogen sulfide production occurred in some strains after irradiation independent of dose and postirradiation storage time. Increases in antibiotic susceptibility also occurred: seven strains became sensitive to β-lactams, two strains became sensitive to antifolates, and one strain each became sensitive to fluoroquinolone, phenicol, nitrofurans, tetracyclines, and aminoglycosides. The results indicate that up to 5.0 kGy of radiation applied to shell eggs inoculated with Salmonella Enteritidis at 4 log CFU per egg is not sufficient for complete elimination of this pathogen from this food matrix.     

Oxidation of Fe(II) in natural waters at high nutrient concentrations

The Fe(II) oxidation kinetic was studied in seawater enriched with nutrients as a function of pH (7.2-8.2), temperature (5-35 °C), and salinity (10-36.72) and compared with the same parameters in seawater media. The effect of nitrate (0-1.77 × 10(-3) M), phosphate (0-5.80 × 10(-5) M) and silicate (0-2.84 × 10(-4) M) was studied at pH 8.0 and 25 °C. The experimental results demonstrated that Fe(II) oxidation was faster in high nutrient concentrations affecting the lifetime of Fe(II) in nutrient rich waters. Silicate displayed the most significant effects on the Fe(II) oxidation rate with values similar to those determined in seawater enriched with all the nutrients. A kinetic model was applied to the experimental results in order to account for changes in the speciation and to compute the fractional contribution of each Fe(II) species to the total rate constant as a function of pH. FeH(3)SiO(4)(+) played a key role in the Fe(II) speciation, dominating the process at pH over 8.4. At pH 8.0, FeH(3)SiO(4)(+) represented 18% of the total Fe(II) species. Model results show that when the concentration of silicate is 3 × 10(-5) M as in high nutrient low chlorophyll areas, FeH(3)SiO(4)(+) contributed at pH 8.0 by 4% increasing the rate to 11% at 1.4 × 10(-4) M. The effect of nutrients, especially silicate, must be considered in any further study in seawater media cultures and eutrophic oceanic areas.