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The primary reservoirs of avian influenza (AI) are wild birds in the orders Anseriformes (ducks, geese, and swans) and Charadriiformes (gulls, terns, and shorebirds). In these hosts, low-pathogenic forms of [...]

Much of the knowledge about cryptochrome function in Drosophila stems from analyzing the [cry.sup.b] mutant. Several features of this variant's light responsiveness imply either that [CRY.sup.b] retains circadian-photoreceptive capacities or that additional CRY-independent light-input routes subserve these processes. Potentially to resolve these issues, we generated cry knock-out mutants ([cry.sup.0]'s) by gene replacement. They behaved in an anomalously rhythmic manner in constant light (LL). However, [cry.sup.0] flies frequently exhibited two separate circadian components in LL, not observed in most previous [cry.sup.b] analyses. Temperature-dependent circadian phenotypes exhibited by [cry.sup.0] flies suggest that CRY is involved in core pacemaking. Further locomotor experiments combined [cry.sup.0] with an externally blinding mutation ([norpA.sup.P24]), which caused the most severe decrements of circadian photoreception observed so far. [cry.sup.b] cultures were shown previously to exhibit either aperiodic or rhythmic eclosion in separate studies. We found [cry.sup.0] to eclose in a solidly periodic manner in light:dark cycles or constant darkness. Furthermore, both [cry.sup.0] and [cry.sup.b] eclosed rhythmically in LL. These findings indicate that the novel [cry.sup.0] type causes more profound defects than does the [cry.sup.b] mutation, implying that [CRY.sup.b] retains residual activity. Because some [norpA.sup.P24] [cry.sup.0] individuals can resynchronize to novel photic regimes, an as-yet undetermined light-input route exists in Drosophila.

A previous study of histone H3 in Saccharomyces cerevisiae identified a mutant with a single amino acid change, leucine 61 to tryptophan, that confers several transcriptional defects. We now present several lines of evidence that this H3 mutant, H3-L61W, is impaired at the level of transcription elongation, likely by altered interactions with the conserved factor Spt16, a subunit of the transcription elongation complex yFACT. First, a selection for suppressors of the H3-L61W cold-sensitive phenotype has identified novel mutations in the gene encoding Spt16. These genetic interactions are allele specific, suggesting a direct interaction between H3 and Spt16. Second, similar to several other elongation and chromatin mutants, including spt16 mutants, an H3-L61W mutant allows transcription from a cryptic promoter within the FLO8 coding region. Finally, chromatin-immunoprecipitation experiments show that in an H3-L61W mutant there is a dramatically altered profile of Spt16 association over transcribed regions, with reduced levels over 5'-coding regions and elevated levels over the 3' regions. Taken together, these and other results provide strong evidence that the integrity of histone H3 is crucial for ensuring proper distribution of Spt16 across transcribed genes and suggest a model for the mechanism by which Spt16 normally dissociates from DNA following transcription.

The social adjustment attitude function that drives homophobia and homophobic communication in fraternities is examined. The results show that attitudes towards homosexual fraternity members and participants' negative communication regarding gays was mediated by members' hetero-identity concern, whereas, attitudes were directly related to perceptions of others' communication.

Analysis of over 2,000 moments of social interaction collected through smartphone-based experience sampling showed that, over a week-long period, people who have experienced negative relations with others (relative to those who have not), interacted with individuals from less-established relationships, perceived less partner responsiveness during interactions (particularly from their established relationship partners), and were more likely to report being alone than engaged in positive communication episodes. People with high negative relations with others also tended to have lower perceptions of affective well-being and relational connection, and greater perceptions of stress-related cognition, during moments of social interaction. Yet, results also indicated that while positive communication appears harder to come by for people with high negative relations with others, these individuals gain outsized benefits from positive interaction when it occurs (e.g., sharper increases in well-being and decreases in stress). This suggests that heightened negative relations with others might lead people to "hyperabsorb" the benefits of positive moments of communication. The results have implications for key perspectives on communication, relational life, and well-being (i.e., affection deprivation, appraisal, implicit vigilance, and resource insufficiency) and suggest potential routes for intervention development for people with difficult relational lives. [ABSTRACT FROM AUTHOR]

Simple Summary: Probiotics are recognized for their beneficial health-promoting properties, through competitive exclusion, promoting maintenance of intestinal epithelial integrity and host immune system homeostasis. The use of some spore-forming bacteria from the genus Bacillus has earned interest as a direct-fed microbial in recent years as a potential alternative to antibiotic growth promoters and growth enhancers. The present study evaluates the use of a Bacillus subtilis spore-based direct-fed microbial (Zymospore®, Vetanco, Villa Martelli, Argentina) compared to an antibiotic growth promoter on the performance of broiler chickens under experimental intestinal challenge conditions. The results suggest that Zymospore® increases the diversity of the broiler fecal microbiota and is an acceptable substitute for commonly used antibiotic growth promoters under defined and non-defined intestinal dysbiosis conditions. Direct-fed microbials (DFM) are added to broiler chicken diets in order to promote the proliferation of beneficial intestinal bacterial populations, which may lead to gains in performance efficiency and, potentially, reduce the level of enteric pathogens in the broiler chickens. The selection and laboratory evaluation of Bacillus subtilis strains as well as the experimental trial results of a novel Bacillus-based commercial DFM product are described. Fifteen wild-type Bacillus subtilis strains were characterized and assayed for their enzyme production capability, spore resistance to pH, salinity, and temperature, and ability to inhibit the growth of E. coli and Salmonella spp. The final DFM formulation was evaluated and compared to an antibiotic growth promoter (AGPs) in two experimental trials. In Experiment 1, broilers were given a defined challenge of Eimeria spp. and Clostridium perfringens to induce intestinal dysbiosis. The optimal dose of the DFM was determined to be 0.3 kg/ton of feed. At this dose, the broilers fed the DFM performed as well as the Flavomycin®-fed broilers. Further, intestinal microbiome analysis indicates that the use of the DFM enhances bacterial diversity of the gut flora by day 5 of age, increasing levels of lactic acid bacteria (LAB) and Clostridiales by 25 days of age, which may enhance the digestion of feed and promote growth of the birds. In Experiment 2, the broilers were raised on recycled litter and given an undefined challenge orally to mimic commercial growth conditions. In this trial, the DFM performed as well as the bacitracin methylene disalicylate (BMD)-11%-fed birds. The results of the present studies suggest that this novel DFM, Zymospore®, improves the performance of broiler chickens under experimental challenge conditions as effective as an AGP, providing a safe and effective substitute to the poultry industry. [ABSTRACT FROM AUTHOR]

The cacophony (cac) locus of Drosophila melanogaster, which encodes a calcium-channel subunit, has been mutated to cause courtship-song defects or abnormal responses to visual stimuli. However, the most recently isolated cac mutant was identified as an enhancer of a comatose mutation's effects on general locomotion. We analyzed the [cac.sup.TS2] mutation in terms of its intragenic molecular change and its effects on behaviors more complex than the fly's elementary ability to move. The molecular etiology of this mutation is a nucleotide substitution that causes a proline-to-serine change in a region of the polypeptide near its EF hand. Given that this motif is involved in channel inactivation, it was intriguing that [cac.sup.TS2] males generate song pulses containing larger-than-normal numbers of cycles--provided that such males are exposed to an elevated temperature. Similar treatments caused only mild visual-response abnormalities and generic locomotor sluggishness. These results are discussed in the context of calcium-channel functions that subserve certain behaviors and of defects exhibited by the original cacophony mutant. Despite its different kind of amino-acid substitution, compared with that of [cac.sup.TS2], [cac.sup.S] males sing abnormally in a manner that mimics the new mutant's heat-sensitive song anomaly.

A new way was developed to isolate rhythmically expressed genes in Drosophila by modifying the classic enhancer-trap method. We constructed a P element containing sequences that encode firefly luciferase as a reporter for oscillating gene expression in live flies. After generation of 1176 autosomal insertion lines, bioluminescence screening revealed rhythmic reporter-gene activity in 6% of these strains. Rhythmically fluctuating reporter levels were shown to be altered by clock mutations in genes that specify various circadian transcription factors or repressors. Intriguingly, rhythmic luminescence in certain lines was affected by only a subset of the pacemaker mutations. By isolating genes near 13 of the transposon insertions and determining their temporal mRNA expression pattern, we found that four of the loci adjacent to the trapped enhancers are rhythmically expressed. Therefore, this approach is suitable for identifying genetic loci regulated by the circadian clock. One transposon insert caused a mutation in the rhythmically expressed gene numb. This novel numb allele, as well as previously described ones, was shown to affect the fly's rhythm of locomotor activity. In addition to its known role in cell fate determination, this gene and the phosphotyrosine-binding protein it encodes are likely to function in the circadian system.

Although male partner resistance to female condom use has been reported, little is understood about circumstances under which partners will agree to female condom use. This study documents the experiences of couples who have worked together to achieve female condom use. As part of a prospective female condom efficacy study, female participants (age 18-34) received a behavioral intervention and an assortment of take-home items. Selected women and their partners were recruited for a qualitative interview focusing on their experience with the female condom. Interviews were transcribed, double-coded, and verified using a standard retrieval coding system. Twenty-six pairs of linked interviews were analyzed dyadically: 9 couples who used the female condom 'consistently,' 12 'experimenters,' and 5 'non-users.' Women who successfully promoted the female condom to their partners used multiple presentation strategies. Initial male partner reaction did not predict continued use beyond the first trial. In conclusion, employment of multiple strategies facilitates successful introduction of the female condom into a sexual partnership. [Article copies available for a fee from The Haworth Document Delivery Service: 1-800-HAWORTH. E-mail address: Website: [c] 2002 by The Haworth Press, Inc. All rights reserved.] KEYWORDS. Female condom, barrier method, contraception, qualitative