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Heterobasidion annosum (Fr.) Bref. sensu lato (s.l.) is a dangerous forest pathogen causing root and butt rot disease in most conifers of the northern hemisphere. This pathogen is most widespread in the forests of Europe and North America. The economic impact on forestry related to tree mortality, reduction in timber yield, and wood rot is calculated in millions of dollars and euros. The genus Heterobasidion (Basidiomycota; Russulales) has been relatively recently separated into three genetically distinct groups (H. annosum, H. insulare and H. araucariae) comprising a total of 12 species and one newly described hybrid taxon. These species are the best studied in terms of the ecology, the physiology of control methods, and the tree’s resistance to the pathogen. The article gives an overview of the symptoms and the etiology of the disease and provides information on ways to recognize the disease and limit the economic damage.

California has a longstanding issue with the Talent Agency Act, which states that only a licensed agent may seek out, or procure, employment for an artist. The TAA has caused major headaches for Hollywood's personal managers, who find their contracts with artists voided for engaging in even minor acts of procurement. Many commentators initiallybelieved that Marathon Entertainment Inc. v. Blasi solved the dilemma. However, it turns out that the Labor Commissioner, who has exclusive jurisdiction to hear claims arising under the TAA, continues to void contracts between California's personal managers and their clients at an alarming rate. Personal managers disapprove of the Labor Commissioner's failure to employ the doctrine of severability, as advised by the Blasi court, to these contracts. In response, the personal managers recently filed a challenge to the constitutionality of the TAA. The United States District Court for the Central District of California, however, dismissed the claim and upheld the constitutionality of the controversial Act. Because this debate spans over one hundred years, and the constitutional challenge was unsuccessful, the authors of this comment advocate a two-fold approach to correcting the dilemma: (1) place the burden of production in Labor Commissioner hearings on the artist to prove that the entire manager contract should be voided, and (2) assess statutory civil penalties to those personal managers who willfully violate the TAA by procuring employment. The authors of this Comment argue that the California legislature should consider applying this approach because it is not only easily adaptable, but also in line with the true purpose of the TAA.

Currently, a change in the species composition of the Białowieża Forest, eastern Poland, is occurring. Parallel to the dying of spruce (Picea abies L. Karst.), caused by Ips typographus (L.), there is a spread of deciduous tree species, among which hornbeam (Carpinus betulus L.) is the most active. Against the background of climate change, it is of interest to consider the possibility of reintroducing relict species in areas occupied until recently by spruce. One of these is silver fir (Abies alba Mill.), which is biologically and ecologically very similar to spruce. The Tisovik tract (the Belarusian part of the Białowieża Forest) is the most northeastern and the only preserved refuge of autochthonous silver fir in the region. Therefore, it is the most suitable source of propagation of this species outside the mountainous part of its range. The target area of our study was a 26-year old artificial stand included in the information system of forest genetic resources conserved in Europe. It was created in 1996 in the Polish part of the Białowieża Forest in the Hajnówka Forest District (Forestry Wilczy Jar) from 10 half-sib families originating from seeds collected in the Tisovik tract. The goal of the study was to assess the influence of provenance factors and spatial structure on productivity and phenotypic variation as measured by diameter (DBH). The study’s initial results showed that the provenance factor’s influence at the pole wood stage manifests itself more clearly than spatial structure. Even within the framework of individual half-sibs, there was a clear differentiation of diameters between investigated trees. Interpretation of the obtained results allowed us to conclude that there is a “threshold value” of the distance between trees in a stand of a given age, which determines the point when its increase no longer contributes to an increase in DBH. The most promising phenotypes were selected for further research and practical actions to reproduce silver fir further.

Forests are an essential component of the natural environment, as they support biodiversity, sequester carbon, and play a crucial role in biogeochemical cycles—in addition to producing organic matter that is necessary for the function of terrestrial organisms. Forests today are subject to threats ranging from natural occurrences, such as lightning-ignited fires, storms, and some forms of pollution, to those caused by human beings, such as land-use conversion (deforestation or intensive agriculture). In recent years, threats from pests and pathogens, particularly non-native species, have intensified in forests. The damage, decline, and mortality caused by insects, fungi, pathogens, and combinations of pests can lead to sizable ecological, economic, and social losses. To combat forest pests and pathogens, biocontrol may be an effective alternative to chemical pesticides and fertilizers. This review of forest pests and potential adversaries in the natural world highlights microbial inoculants, as well as research efforts to further develop biological control agents against forest pests and pathogens. Recent studies have shown promising results for the application of microbial inoculants as preventive measures. Other studies suggest that these species have potential as fertilizers.

In natural environments, plants develop adaptive mechanisms at the cellular and molecular levels to cope with many external factors, e.g., insects and soil pathogens. We studied physiological stress induced by different levels of foliage removal (defoliation 30% and 60%) and by infection of root rot pathogen Phytophthora plurivora on the common Polish tree species, Betula pendula, grown in an open greenhouse. This study showed that P. plurivora damaged the root system which negatively impacted all morphological parameters. However the loss of 30% of the leaves had a positive effect on defense responses. Chlorophyll-a fluorescence parameters indicated a decrease in photosynthetic efficiency in defoliated plants, but plants inoculated with the pathogen had a higher performance index showing increased vigor of the infected plant than birches. The study demonstrated the intense immunity response of birch to P. plurivora through the expression of Hsp90 and Hsp83 genes. The trees weakened by P. plurivora became more susceptible to infection by Erysiphe ornata var. ornata.

Volunteering has been associated with increased social interactions and reduced feelings of loneliness among older adults. However, a growing number of social network analyses (SNA) conducted in the general population outside of volunteering contexts suggest that lonely individuals tended to interact with other lonely individuals in the network, reinforcing loneliness through peer associations. To better understand the psychosocial impact of peer interactions among older adults within volunteer programs, this study examines how older adults' loneliness is correlated with their peers' loneliness within the Senior Companions Program (SCP). This study collected information on the social networks within an SCP in a Midwest Metropolitan and feelings of loneliness among low-income Russian, Khmer, Somali, Nepali, and English-speaking older volunteers (N = 41). A linear network autocorrelation model (LNAM) was constructed to quantify how volunteers' loneliness is correlated with their peers' loneliness within SCP. The LNAM results indicated that less lonely volunteers tended to make friends with lonelier volunteers (ρ = -.06, p <.05) in SCP even when accounting for statistical controls. The finding that more and less lonely individuals connect indicates an altruistic tendency for less lonely individuals to interact with those who are lonelier. This may be an important pathway by which volunteering addresses loneliness. [ABSTRACT FROM AUTHOR]

Therapeutic communities (TCs) have a strong record of maintaining high quality social climates in prison units. One possible reason for this is the system of mutual monitoring among TC residents, based on the assumption that peer affirmation of behavior in accord with TC norms, and peer correction of behavior contrary to TC norms, will lead to increased resident prosocial behavior. Laboratory experiments have demonstrated that such peer monitoring can lead to cooperation, but there has been no quantitative test of this hypothesis in an actual TC. In this article we test this assumption by using the affirmations that residents of three different TCs send as a measure of prosocial behavior following the reception of peer affirmations and corrections. At all three facilities residents send more affirmations following the reception of both affirmations and corrections, with this relationship being stronger and longer lasting after receiving affirmations. No other variable consistently predicts the number of affirmations that residents send to peers. These findings imply that mutual monitoring among TC residents can lead to increased levels of prosocial behavior within the facility, and that prosocial behavior in response to peer affirmations plays a key role. (Contains 4 tables.)

Associations between suicidal behavior and social-ecological variables were examined among 1,618 Latina high school students (mean age = 15) from the nationally representative Add Health sample (68% were U.S.-born). Ideations were associated with having a suicidal friend, lower perceived father support, and overall parental caring. Attempts were associated with having a suicidal friend, and lower perceived teacher and parental support. Peer and mother relationship variables were not predictors of ideations or attempts. The protective role of father and teacher support has not previously been emphasized in the literature. Strengthening connections to parents and teachers may reduce suicidal behavior in adolescent Latinas. (Contains 2 tables.)

This article extends the work of Kellam, Ling, Merisca, Brown and Ialongo (1998) by applying a mathematical model of competition between children to peer contagion in the aggressive behaviors of elementary school students. Nonlinearity in the relationship between group aggression and individual aggression at 2-year follow-up is present. Consistent with the findings of Kellam et al. (1998). hierarchical linear modeling indicates that the relationship is statistically significant for those students whose initial parental ratings of aggressive behavior were above the sample median. In the context of competition between students, the behavior of initially aggressive students may be negatively reinforced. Lowering aggression in the school environment may therefore be the most effective way to lower the level of these students' aggressive behavior.KEY WORDS: aggressive behavior; ecological psychology; elementary school; students; peers; red queen model.

This exploratory study uses observations of the aggressive behavior of elementary school boys during three successive recess periods to test the hypothesis that aggressive behavior can spread between recess periods through peer contagion. If this hypothesis is correct, aggressive behaviors during the second recess period should mediate any correlation between aggressive behaviors during the first and third periods. Structural equation modeling supports the mediating role of the second period. This finding suggests that peer contagion in aggressive behaviors can occur quite rapidly and adds theoretical support to the use of proactive interventions within schools that curtail aggressive behaviors before they have the opportunity to spread. Implications for schools related to supervision in unstructured settings throughout the school day are discussed. (Contains 1 table, 3 figures, and 3 notes.)