Factors affecting the numbers of expected viable lactic acid bacteria in inoculant applicator tanks.

The application of correct numbers of viable microorganisms to forages at the time of ensiling is one of the most important factors affecting the probability of a beneficial effect from an inoculant. The objective of this study was to determine relationships between numbers of expected lactic acid bacteria (LAB) from silage inoculants in application tanks and various factors that might affect their viability. The pH and temperature of inoculant-water mixes were measured in applicator tanks (n=53) on farms in Wisconsin, Minnesota, South Dakota, and California during the corn harvest season of 2012. Samples were collected on-farm and plated on de Man, Rogosa, and Sharpe agar to enumerate LAB and establish the number of viable LAB (cfu/mL). Expected numbers of LAB were calculated from the minimum label guarantees for viable bacteria and mixing rates with water. In addition, the pH of the inoculant-water mixes at sampling, the ambient temperature at sampling, and the length of time that the samples had been in the tank were measured and obtained. The log difference between the measured and expected numbers of LAB was calculated and expressed as ΔM - E in log scale. Ambient temperature at sampling had no relationship with time in the tank or ΔM - E. Most (83%) of the inoculants had been mixed with water in the applicator tanks for <10h. For these samples, a negative linear correlation (R2=0.36) existed between time that the inoculant-water mixes were in the applicators tanks and ΔM - E. The pH of the inoculant-water mixes was also negatively correlated (R2=0.28) with time in the applicator tank, but pH was not related to ΔM - E. The temperatures of the inoculant-water mixtures were negatively correlated with ΔM - E (R2=0.39). Seven of 8 samples whose ΔM - E were at least -0.95 or more lower than expected (equivalent of about 1 or more log concentration less than expected) had water temperatures above 35°C. These data support our previous laboratory findings and suggest that high temperatures of inoculant-water mixes have the potential to negatively affect the final application rate of some inoculants, which may affect their overall effectiveness to improve silage fermentation.

The effect of an exogenous protease on the fermentation and nutritive value of high-moisture corn.

The objective of this study was to determine if treating high-moisture corn at harvest with an exogenous protease could accelerate the increase in in vitro ruminal starch degradation that is normally found with advancing times of ensiling. Ground high-moisture corn (HMC; 73% dry matter) was untreated or treated with an exogenous protease to achieve a final concentration of 2,000 mg of protease/kg of fresh corn. Corn was ensiled in laboratory-scale bags (approximately 500 g) that were evacuated of air, heat-sealed, and stored at 22 to 23°C for 70 and 140 d. Samples of freshly treated corn samples were collected to represent d 0 samples. Treatment of HMC with protease did not affect the gross populations of lactic acid bacteria or yeasts throughout the ensiling period. Treatment of HMC with protease resulted in higher concentrations of lactic acid and ethanol after 70 but not 140 d of ensiling. Concentrations of crude protein, water-soluble carbohydrates, and starch were unaffected by treatment with protease within each sampling day. After 70 or 140 d of ensiling, HMC that was treated with protease had higher concentrations of soluble protein (as a % of crude protein) and NH3-N, and had lower concentrations of prolamin protein, compared with untreated corn. In vitro rumen degradability (7-h incubation) of starch was greater in protease-treated versus untreated corn at all sampling days but the difference was more pronounced after 70 and 140 d compared with d 0. Concentrations of soluble protein and NH3-N were positively correlated with in vitro starch degradation. Conversely, the concentrations of prolamin protein in HMC were negatively correlated with in vitro starch degradation. Treating HMC with an exogenous protease could be a method to obtain greater potential for ruminal starch fermentation after a relatively short period of ensiling.

Effects of an exogenous protease on the fermentation and nutritive value of corn silage harvested at different dry matter contents and ensiled for various lengths of time.

The objective of this experiment was to evaluate the effects of adding an experimental protease to corn plants harvested at different maturities on silage fermentation and in vitro ruminal starch digestibility (IVSD). Corn plants were harvested at maturities resulting in plants with 31 or 40% dry matter (DM). Plants were chopped, kernel processed, and treated with (1) only a 0.1 M phosphate buffer (pH 5.5, 5% vol/wt of fresh forage), (2) buffer with protease to obtain a final concentration of 20mg of protease/kg of wet forage, and (3) buffer with protease to obtain a final concentration of 2,000 mg of protease/kg of wet forage. Treated forages (about 500 g) were ensiled in nylon-polyethylene pouches and stored between 21 and 23°C for 0, 45, 90, and 150 d. Data were analyzed as a 2 × 3 × 4 factorial arrangement of treatments, with the main effects of harvest DM, dose of protease, days of ensiling, and their interactions. The treatment with the highest dose of protease resulted in more robust fermentations across harvest DM with higher concentrations of lactic and acetic acids compared with untreated silage. Concentrations of soluble protein (% of crude protein) increased with time of ensiling, regardless of DM content at harvest. However, averaged over both harvest DM contents, it increased by 37% for silages treated with the high dose of protease compared with an average 11% increase for untreated silages and silage treated with the low dose of protease, between d 0 and 45. Averaged over both harvest DM contents, the concentration of soluble protein peaked in silages treated with the high dose of protease after 45 d of ensiling, whereas it peaked at d 90 in untreated silages and silage treated with the low dose of protease. Similar changes occurred in the concentration of NH3-N due to length of ensiling and treatment with protease. In fresh forages, the concentration of starch for early- and late-harvested forages was similar, but IVSD was lower in the latter. After 45 d of ensiling, IVSD was highest in both early- and late-harvested silages that were treated with the high level of protease. After 150 d of ensiling, IVSD was similar among silages treated with protease, regardless of DM at harvest. Treating corn plants with a high dose of an experimental protease at harvest accelerated proteolysis during ensiling, resulting in corn silages with levels of IVSD after 45 d of ensiling that were only obtained in untreated corn silages after 150 d of ensiling.

Physical and sexual abuse and associated mental disorders among alcoholic inpatients.

OBJECTIVE: The purpose of this study was to investigate the adult psychiatric correlates of childhood abuse among alcoholic inpatients. METHODS: The 802 patients, who included 321 women, were admitted to one of five New York State alcohol treatment inpatient centers. Each patient was interviewed, and sexual and physical abuse history, DSM-III diagnosis, and other characteristics were recorded. RESULTS: The overall prevalence of reported childhood abuse was 59% for women and 30% for men. Family history of alcoholism was associated with higher levels of physical and sexual abuse. Gender differences in types of childhood abuse (i.e., sexual abuse only, physical abuse only, dual abuse) were evident; 49% of the women and 12% of the men reported sexual abuse (with or without physical abuse), 33% of the women and 24% of the men reported physical abuse (with or without sexual abuse), and 23% of the women and 5% of the men reported dual abuse. Abuse status, and especially dual abuse, was associated with higher rates of antisocial personality disorder and suicide attempts among women and men, with generalized anxiety disorder among women, and with major depression among men. CONCLUSIONS: The findings highlight the long-term associations between sexual and physical abuse and adult coexisting mental disorders among alcoholic inpatients. Addressing unresolved intrapsychic trauma associated with childhood abuse may increase the efficacy of treatment outcomes and reduce relapse rates among alcoholics.

Coexisting problems and alcoholic family risk among adolescents.

A substantial subset of nonclinical adolescents reported single or multiple problems with regard to drinking behavior, depressive symptoms, and delinquency. Similar to previous research, boys reported higher levels of heavy and problematic drinking, whereas girls reported higher levels of depressive symptoms. Higher levels of alcohol involvement were associated with higher levels of delinquency for both boys and girls. Family history of alcoholism was associated with an overrepresentation of problem drinkers (as well as abstainers). These findings are fairly consistent with the adult alcohol typology literature in identifying coexisting problem patterns for the triumvirate of problem drinking, depressive symptoms, and antisocial behavior. Furthermore, these data support the manifestation of these patterns prior to the onset of alcohol dependence (and maybe alcohol abuse). Future longitudinal research needs to focus on the short- and long-term patterns of problem behaviors among adolescents and to identify common and unique precursors, correlates, and consequences associated with varying levels of alcohol involvement.

Individual and situational markers of condom use and sex with nonprimary partners among alcoholic inpatients: findings from the ATRISK Study.

Alcoholics in treatment have demonstrated increased rates of HIV risk behavior and infection. This study explored individual and situational variables associated with HIV risk behaviors such as condom nonuse and sex with nonprimary partners reported during structured interviews of 802 male and female alcoholic inpatients. Logistic regression analyses indicated that person variables, sexual history variables, and situation variables were independently associated with sexual risk behavior in the most recent episode. Results of paired t tests revealed that participants who had engaged in sex with both primary and nonprimary partners during the previous 6 months reported significantly more frequent alcohol and condom use in situations involving sex with nonprimary partners. Prevention efforts need to target alcoholic inpatients as a group and, within this group, to focus on both high-risk individuals and high-risk situations.

PIP: Interviews conducted with 802 male and female inpatients at five alcohol treatment centers in the US underscored the importance of directing human immunodeficiency virus (HIV) prevention campaigns at this population. Logistic regression analyses indicated that failure to use condoms was predicted, among men, by prior condom nonuse, more lifetime sexually transmitted disease (STD) episodes, sex with a primary partner, failure to discuss prevention before intercourse, and the interaction between condom nonuse history and choice of a nonprimary partner; among women, these predictors were prior nonuse of condoms and failure to discuss STD prevention. Neither daily alcohol use nor substance use in conjunction with the sexual episode were significantly associated with failure to use a condom. Within-subject analysis, aimed at determining whether alcohol use during sex and nonprimary partner choice were situationally linked, revealed that the rate of sober sex was significantly lower in intercourse involving a nonprimary partner. Among participants who had sex with both primary and nonprimary partners in the six months preceding the interview, situations involving intercourse with nonprimary partners were more likely to include both alcohol and condom use. Only 52% of alcoholics surveyed had been tested for HIV infection. Given the situational association between alcohol use and sex with a nonprimary partner, avoidance of this scenario has the potential to prevent both alcohol relapse and HIV infection.

Substance use, risky behaviors, and victimization among a US national adolescent sample.

Data from the National Adolescent Student Health Survey were used to study the interrelations among substance use, risky (dangerous) behaviors, and victimization among 8th and 10th graders. Pearson correlations indicated significant associations between substance use and both higher levels of risky behaviors (e.g., hitchhiking, going on a blind date) and victimization among adolescents. Regression analyses indicated the potency of risky behaviors as a predictor of victimization for male adolescents, and a significant risky behavior by illicit drug use interaction for female adolescents. Results are discussed with regard to potential short- and long-term health consequences of risky behaviors and violent victimization for psychological development in adolescence and adulthood.

Intrapersonal and interpersonal functioning among middle-aged female adult children of alcoholics.

This study examined group differences among a middle-aged, middle-class, community sample (N = 616) of female adult children of alcoholics (ACOAs) and female non-ACOAs with regard to features of intra- and interpersonal functioning. Consistent with previous research, ACOAs reported higher levels of depression and lower levels of self-esteem. ACOAs also reported lower levels of perceived social support, family cohesion, and marital satisfaction and higher levels of marital conflict. ACOAs also indicated more parental role distress and perceived themselves as more powerless than non-ACOAs to control the actions of their offspring. ACOAs were more likely to drink for coping purposes (e.g., to relieve stress), although their level of alcohol consumption did not differ significantly from that of non-ACOAs. Although consistent differences were indicated between groups, ACOAs were still functioning in the nonpathological range on all measures.

Depressive symptoms and cigarette smoking among middle adolescents: prospective associations and intrapersonal and interpersonal influences.

Using data from a 4-wave longitudinal study with a school-based sample of 1,218 middle adolescents, the authors investigated the directionality (e.g., unidirectionality and bidirectionality) of the prospective relationship between depressive symptoms and cigarette use within the context of potential confounding variables and common and unique intrapersonal and interpersonal predictors. Findings indicated that serious and persistent depressive symptoms were prospective predictors of increased cigarette use across time, after controlling for baseline levels of smoking. Similarly, heavy and persistent smoking prospectively predicted increases in depressive symptoms. Intrapersonal and interpersonal predictors of cross-temporal changes in depressive symptoms and cigarette use were more unique than common. Latent growth curve modeling indicated a quadratic trend in adolescent cigarette smoking across time with an initial acceleration followed by a deceleration, though there was substantial intraindividual variation in individual trajectories.

Problem drinking and depression among DWI offenders: a three-wave longitudinal study.

Longitudinal data collected at 3 occasions of measurement from a convicted driving-while-intoxicated sample (n = 302) were used to study the interrelations between problem drinking and depressive symptomatology. Time intervals between occasions of measurement were approximately 9 months. Cross-lagged latent variable models indicated that higher levels of depression at Time 1 were significantly associated with lower levels of problem drinking at Time 2. Similarly, higher levels of problem drinking at Time 1 were significantly associated with lower levels of depression at Time 2. However, the direction of effects for the cross-lagged coefficients were reversed for the Time-2-Time-3 relations. Higher levels of depression at Time 2 were significantly associated with higher levels of problem drinking at Time 3, and higher levels of problem drinking at Time 2 were associated with higher levels of depression at Time 3. The results are interpreted to reflect a biphasic process.

A longitudinal study of antisocial behaviors in early adolescence as predictors of late adolescent substance use: gender and ethnic group differences.

Data from the National Longitudinal Youth Survey (NLSY) were analyzed to study interrelationships between antisocial behaviors in early adolescence (ages 14-15) and late adolescent alcohol and drug use 4 years later (when adolescents were 18-19). Correlations between classes of antisocial behaviors in early adolescence and substance use in late adolescence were of higher magnitude and more uniform for men than for women; for women, property offenses (e.g., vandalism) in early adolescence were more highly associated with alcohol use, alcohol-related problems, and illicit drug use in late adolescence than with either status offenses or transgressions against persons. Multiple regression analyses indicated that early-adolescent substance involvement was a significant predictor of late-adolescent alcohol and drug use. Additional significant predictors included early adolescent general delinquency, male gender, and non-Black ethnicity.

Coping strategies, drinking motives, and stressful life events among middle adolescents: associations with emotional and behavioral problems and with academic functioning.

A sample of 733 middle adolescents was used to study interrelations among coping strategies, drinking motives, stressful life events (major, daily positive, and daily negative), emotional and behavioral problems, and academic functioning. A main-effects (vs. stress-buffering) model was supported. Some predictors (e.g., task-oriented coping, major stressful events) were general in their predictive relations to the outcome variables, whereas others were highly specific (e.g., emotion-focused coping predicting depressed affect). Overall, the predictors accounted for 22-53% of the variance in regression equations. Positive daily events predicted higher levels of alcohol use, alcohol problems, and delinquent activity; as well as higher academic performance and lower levels of depressed affect.

The trading of sex for money or drugs, sexually transmitted diseases (STDs), and HIV-related risk behaviors among multisubstance using alcoholic inpatients.

Data from 802 multisubstance using alcoholic inpatients (481 men and 321 women) were analyzed to determine whether trading sex for money or drugs was associated with self-reported STDs, self-reported HIV infection, and perceptions of current and future probable infection. Logistic and ordinal polychotomous regression models were used to evaluate the statistical significance of sex trade on STDs and HIV-related behaviors while controlling for other potential confounding variables such as cocaine abuse and i.v. drug use. Involvement in sex trade was associated with higher cocaine abuse, with STDs, and with self-reported HIV infection. The multivariate (adjusted) models supported the significance of sex trade with regard to STDs and HIV-related behaviors. The findings indicated that, among these multisubstance using alcoholic inpatients, high levels of trading sex for money or drugs were independently associated with self-reported STDs, a cofactor of HIV infection, as well as self-reported HIV infection and perceptions of risk for infection.

A discriminant function analysis of various interferon parameters among alcoholics and heavy smokers.

A three-group design of alcoholics, heavy smokers and controls was used to investigate the status of the interferon system, including natural killer cell activity. Group differences were indicated via discriminant function analysis which correctly classified 86% of subjects. Test-retest relations were investigated for 14 subjects following a 30-day alcoholic inpatient program. Whereas significant immune suppression was indicated at the time of detoxification, recovery was evident at the 30-day follow-up. Results are discussed in terms of the significance of alcohol abuse on immune system functioning with consequences for susceptibility to viruses, bacteria and medical illnesses.

Concepts and issues in COA research.

Estimates of the number of children of alcoholics (COA's) and the prevalence of alcohol use disorders among them can vary widely from study to study depending on research design features such as sample selection, data collection strategies, and assessment methods. Although investigators agree that COA's are at higher risk for developing alcohol use disorders than children of nonalcoholics, problems with alcohol are not an inevitable consequence of COA status. Recent research has identified numerous biological, psychological, and social factors associated with a family history of alcoholism that may play a role in determining whether COA's will develop an alcohol use disorder. The conceptual model presented in this article gives a general overview of how such risk factors can interact with life stressors to influence alcohol-related behavior in COA's. (Subsequent articles in this issue explore some of the specific factors identified in the model in greater depth.).

Temperament and novelty seeking in adolescent substance use: convergence of dimensions of temperament with constructs from Cloninger's theory.

This study investigated the convergence of temperament dimensions with constructs from C. R. Cloninger's (1987a) theory using data from a sample of 949 adolescents (M age = 13.6 years). Substantial convergence was found, and both types of constructs were related in predicted ways to self-regulation variables and adolescent substance use. Structural modeling procedures tested a mediational model for substance use; results showed mediation through self-control, academic competence, negative life events, and deviant peer affiliations. Interactions indicated that substance use could be predicted from a balance of systems for good control and poor control. Poor self-control was present for dimensions implicated in both externalizing and internalizing disorders. Results are discussed with reference to self-regulation models of substance use and the comorbidity of substance abuse and mental disorder.

Causal models of adolescent substance use: an examination of gender differences using distribution-free estimators.

On the basis of previous literature (Hays, Widaman, DiMatteo, & Stacey, 1987; Huba, Wingard, & Bentler, 1981), four alternative causal models of substance use were specified, estimated, and evaluated for adequacy of statistical fit for samples of White male (N = 9,164) and female (N = 8,421) adolescents. Results supported the adequacy of a four-variable simplex model, in which alcohol use predicted marijuana use, and marijuana use predicted enhancer and dampener hard drug use. The four-variable simplex model was robust across the male and female adolescent samples. In addition, we found comparisons of maximum likelihood and asymptotically distribution-free estimators to be relatively robust across the causal models specified with respect to the magnitude of the parameter estimates, and with respect to the significance levels of the critical ratios, although chi-square model fit statistics for the maximum likelihood estimates were highly inflated.

Cumulative sexual intercourse patterns among middle adolescents: problem behavior precursors and concurrent health risk behaviors.

PURPOSE: The purpose of this study is to document associations among problem behaviors in childhood and early adolescence and several health risk behaviors in middle adolescence, including a cumulative index of sexual intercourse risk. METHOD: A nontreatment sample of 1167 10th and 11th grade students was recruited from three homogeneous suburban high schools in western New York. Intercourse activity and number of sexual partners were assessed four times at 6-month intervals over a 2-year period via self-report questionnaires administered in classroom settings. RESULTS: Sexual intercourse activity, once initiated, was found to be relatively persistent, rather than sporadic, for most adolescents. Repeated intercourse experience with multiple partners over the assessed time periods was associated with higher levels of externalizing childhood behavior problems, earlier onset of antisocial behaviors and substance use, and higher concurrent substance use. An avoidant, withdrawn behavioral style in childhood was associated with lower rates of sexual involvement in adolescence. CONCLUSIONS: Temporal linkages among childhood precursors and adolescent sexual behaviors were identified as critical to understanding adolescent risk behaviors. These cross-time relationships may identify potential targets for future intervention/prevention efforts among high risk subsamples of children and adolescents.

Gender-specific pathways between maternal depressive symptoms, family discord, and adolescent adjustment.

Relations among maternal depressive symptoms, family discord, and adolescent psychological adjustment were examined in a sample of 443 middle adolescents and their mothers. Histories of maternal depressive symptoms, gathered at 3 occasions with 6-month intervals, were related to subsequent adolescent reports of depressive symptoms, conduct problems, and academic difficulties for girls but not for boys. Mediational tests indicated that girls' greater vulnerability to family discord (e.g., marital discord, low family intimacy, parenting impairments) accounted for the impact of maternal depressive symptoms on their social and emotional adjustment. Analyses suggest that family discord is a strong mediator in the development of girls' conduct disturbances and a modest mediator of girls' depressive symptoms. Results are discussed within a framework that integrates interpersonal models of parental depressive symptoms with the gender intensification hypothesis.

A retrospective measure of childhood behavior problems and its use in predicting adolescent problem behaviors.

Confirmatory factor analysis was used to support the dimensional structure of a four-factor retrospective measure of childhood behavior problems with a large, nonclinical adolescent sample. Acceptable levels of internal consistency and low-to-moderate levels of parent-adolescent interrater agreement were indicated for the four factors of attentional deficit/hyperactivity, oppositional behavior, conduct disorder symptoms and avoidance behaviors. The externalizing childhood problems (i.e., attentional deficit/hyperactivity, oppositional behavior, conduct disorder) were associated significantly with both internalizing (depression) and externalizing (e.g., alcohol consumption, delinquent activity) adolescent problem behaviors, as well as with an earlier age of onset for substance use. Avoidant behaviors in childhood were associated specifically with depressive symptomatology in adolescence. Results are discussed with regard to the role of childhood problems as precursors to adolescent/adult disorders.