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Many technological applications in photonics require devices to function reliably under extreme conditions, including high temperatures. To this end, materials and structures with thermally stable optical properties are indispensable. State-of-the-art thermal photonic devices based on nanostructures suffer from severe surface diffusion-induced degradation, and the operational temperatures are often restricted. Here, we report on a thermo-optically stable superabsorber composed of bilayer refractory dielectric materials. The device features an average absorptivity ∼95% over >500 nm bandwidth in the near-infrared regime, with minimal temperature dependence up to 1500 °C. Our results demonstrate an alternative pathway to achieve high-temperature thermo-optically stable photonic devices.

● First evidence of BNI capacity in canola. ● BNI level was higher in canola cv. Hyola 404RR than in B. humidicola, the BNI positive control. ● BNI in canola may explain increased N immobilization and mineralization rates following a canola crop which may have implications for N management in rotational farming systems that include canola. A range of plant species produce root exudates that inhibit ammonia-oxidizing microorganisms. This biological nitrification inhibition (BNI) capacity can decrease N loss and increase N uptake from the rhizosphere. This study sought evidence for the existence and magnitude of BNI capacity in canola ( Brassica napus). Seedlings of three canola cultivars, Brachiaria humidicola (BNI positive) and wheat ( Triticum aestivum) were grown in a hydroponic system. Root exudates were collected and their inhibition of the ammonia oxidizing bacterium, Nitrosospira multiformis, was tested. Subsequent pot experiments were used to test the inhibition of native nitrifying communities in soil. Root exudates from canola significantly reduced nitrification rates of both N. multiformis cultures and native soil microbial communities. The level of nitrification inhibition across the three cultivars was similar to the well-studied high-BNI species B. humidicola. BNI capacity of canola may have implications for the N dynamics in farming systems and the N uptake efficiency of crops in rotational farming systems. By reducing nitrification rates canola crops may decrease N losses, increase plant N uptake and encourage microbial N immobilization and subsequently increase the pool of organic N that is available for mineralization during the following cereal crops.

Some have argued that the field of kinesiology is losing its vitality because of overspecialization and fragmentation; exercise science scholars are no longer able to find points of convergence with those in kinesiology subdisciplines other than their own. I contend, however, that this is not an accurate portrayal of every subdiscipline. Qualitative research in the sociology of physical activity lends itself to an interdisciplinary and broadly based understanding of human movement. To illustrate my claim, I present and explain six dimensions of the body: the imagined body, the consumer body, the disciplined body, the practiced body, the discursive body, and the transgressive body. Each of these dimensions ("bodies" of knowledge) may be thought of as a "social movement", both in the literal sense of moving one's body in socially constructed ways, but also in the figurative sense of scholarly movement that crosses and blurs disciplinary boundaries.

This study explores the female body ideal and its implications for health and fitness practices in African-American culture. Employing Patricia Hill Collins's (1986) notion of the "outsider-within," we analyze a focus group discussion on women's body ideals, exercise, and fitness. Our group comprises 9 young, college-educated African-American women who reject the White-American ideal of thinness, yet recognize that the "thick" (full-figured) African-American ideal is problematic, especially when considered in the context of the dominant culture's biomedical model. Prompted by their examination of popular mass media images selected by the coauthors, the women discursively negotiate between two contrasting cultural standards: an unrealistically slender body ideal and a heavier body weight and shape that may lend itself to the kinds of diseases associated with obesity.

For example, in Figure 2, the photo on the left shows Margaret cutting the mundalurra bark and on the right, Rhonda drew Margaret cutting the tree for sugarbag (bush honey). Specifically, as the hill will soon show, jidan la Kantri enabled the research process to respond to the ways Country inspires, interrupts and redirects the stories of Ngalakgan storytellers, as well as the ways in which Country tells its own stories. (Margaret, Rhonda and Lillian, 8 May 2019 At the bottom of hill about to walk up See https://youtu.be/qhqiiL1%5f1rM for spoken story) The incomprehensible cruelty which Duncan and the prisoners endured, and were forced into, is evident in Margaret's words and tone. Keywords: Co-creative multisensory methods; recuperative research; decolonizing approaches; indigenous methodologies; roper Kriol; participatory research; métodos co-creativos multisensoriales; investigación recuperativa; enfoques descolonizantes; metodologías indígenas; Roper Kriol; investigación participativa; méthodes multisensorielles de cocréation; recherche de récupération; approches de décolonisation; méthodologies indigènes; recherche participative EN Co-creative multisensory methods recuperative research decolonizing approaches indigenous methodologies roper Kriol participatory research ZH métodos co-creativos multisensoriales investigación recuperativa enfoques descolonizantes metodologías indígenas Roper Kriol investigación participativa méthodes multisensorielles de cocréation recherche de récupération approches de décolonisation méthodologies indigènes recherche participative 1097 1117 21 10/12/22 20221001 NES 221001 1. [Extracted from the article]

Argues that mediation is extension of the self along paths of social practice, discourse, and technology. Argues that communication should be studied from that perspective, which is more consistent with the everyday experience of communication. Illustrates the theory with an analysis of the empowerment and disempowerment of men and women through watching televised football. (RS)

Examines specularity (the pleasure derived from looking at television) in the context of sports. Argues that televised sports' popularity reflects: (1) fetishism (motivation by fascinated desire); (2) voyeurism (uninvited viewing); and (3) narcissism (identification with athletes). Describes a study of sports telecast viewing. Argues against "totalization" of television criticism through overgeneralization about programing and viewing. (SG)

Porphyromonas gingivalis, a Gram-negative oral anaerobe, is strongly associated with chronic adult periodontitis, and it utilizes FimA fimbriae to persistently colonize and evade host defenses in the periodontal crevice. The FimA-related gene cluster (the fim gene cluster) is positively regulated by the FimS-FimR two-component system. In this study, comparative analyses between fimbriate type strain ATCC 33277 and fimbria-deficient strain W83 revealed differences in their fimS loci, which encode FimS histidine kinase. Using a reciprocal gene exchange system, we established that FimS from W83 is malfunctional. Complementation analysis with chimeric fimS constructs revealed that W83 FimS has a defective kinase domain due to a truncated conserved G3 box motif that provides an ATP-binding pocket. The introduction of the functional fimS from 33277 restored the production, but not polymerization, of endogenous FimA subunits in W83. Further analyses with a fimA-exchanged W83 isogenic strain showed that even the fimbria-deficient W83 retains the ability to polymerize FimA from 33277, indicating the assembly of mature FimA by a primary structure-dependent mechanism. It also was shown that the substantial expression of 33277-type FimA fimbriae in the W83 derivative requires the introduction and expression of the functional 33277 fimS. These findings indicate that FimSR is the unique and universal regulatory system that activates the fim gene cluster in a fimA genotype-independent manner. doi: 10.1128/JB.01474-09

Periodontitis is a biofilm-mediated disease. Porphyromonas gingivalis is an obligate anaerobe consistently associated with severe manifestations of this disease. As an opportunistic pathogen, the ability to proliferate within and disseminate from subgingival biofilm (plaque) is central to its virulence. Here, we report the isolation of a P. gingivalis transposon insertion mutant altered in biofilm development and the reconstruction and characterization of this mutation in three different wild-type strains. The mutation responsible for the altered biofilm phenotype was in a gene with high sequence similarity (~61%) to a glycosyltransferase gene. The gene is located in a region of the chromosome that includes up to 16 genes predicted to be involved in the synthesis and transport of capsular polysaccharide. The phenotype of the reconstructed mutation in all three wild-type backgrounds is that of enhanced biofilm formation. In addition, in strain W83, a strain that is encapsulated, the glycosyltransferase mutation resulted in a loss of capsule. Further experiments showed that the W83 mutant strain was more hydrophobic and exhibited increased autoaggregation. Our results indicate that we have identified a gene involved in capsularpolysaccharide synthesis in P. gingivalis and that the production of capsule prevented attachment and the initiation of in vitro biofilm formation on polystyrene microtiter plates.

Mutans streptococci are major etiological agents of dental caries, and several of their secreted products contribute to bacterial accumulation on teeth. Of these, Streptococcus mutans glucan binding protein B (GbpB) is a novel, immunologically dominant protein. Its biological function is unclear, although GbpB shares homology with a putative peptidoglycan hydrolase from S. agalactiae and S. pneumoniae, indicative of a role in murein biosynthesis. To determine the cellular function of GbpB, we used several approaches to inactivate the gene, analyze its expression, and identify interacting proteins. None of the transformants analyzed were true gbpB mutants, since they all contained both disrupted and wild-type gene copies, and expression of functional GbpB was always conserved. Thus, the inability to obtain viable gbpB null mutants supports the notion that gbpB is an essential gene. Northern blot and real-time PCR analyses suggested that induction of gbpB expression in response to stress was a strain-dependent phenomenon. Proteins that interacted with GbpB were identified in pull-down and coimmunoprecipitation assays, and these data suggest that GbpB interacts with ribosomal protein L7/L12, possibly as part of a protein complex involved in peptidoglycan synthesis and cell division.

We used Porphyromonas gingivalis gene microarrays to compare the total gene contents of the virulent strain W83 and the avirulent type strain, ATCC 33277. Signal ratios and scatter plots indicated that the chromosomes were very similar, with approximately 93% of the predicted genes in common, while at least 7% of them showed very low or no signals in ATCC 33277. Verification of the array results by PCR indicated that several of the disparate genes were either absent from or variant in ATCC 33277. Divergent features included already reported insertion sequences and ragB, as well as additional hypothetical and functionally assigned genes. Several of the latter were organized in a putative operon in W83 and encoded enzymes involved in capsular polysaccharide synthesis. Another cluster was associated with two paralogous regions of the chromosome with a low G+C content, at 41%, compared to that of the whole genome, at 48%. These regions also contained conserved and species-specific hypothetical genes, transposons, insertion sequences, and integrases and were located adjacent to tRNA genes; thus, they had several characteristics of pathogenicity islands. While this global comparative analysis showed the close relationship between W83 and ATCC 33277, the clustering of genes that are present in W83 but divergent in or absent from ATCC 33277 is suggestive of chromosomal islands that may have been acquired by lateral gene transfer.

The complete 2,343,479-bp genome sequence of the gram-negative, pathogenic oral bacterium Porphyromonas gingivalis strain W83, a major contributor to periodontal disease, was determined. Whole-genome comparative analysis with other available complete genome sequences confirms the close relationship between the Cyto-phaga-Flavobacteria-Bacteroides (CFB) phylum and the green-sulfur bacteria. Within the CFB phyla, the genomes most similar to that of P. gingivalis are those of Bacteroides thetaiotaomicron and B. fragilis. Outside of the CFB phyla the most similar genome to P. gingivalis is that of Chlorobium tepidum, supporting the previous phylogenetic studies that indicated that the Chlorobia and CFB phyla are related, albeit distantly. Genome analysis of strain W83 reveals a range of pathways and virulence determinants that relate to the novel biology of this oral pathogen. Among these determinants are at least six putative hemagglutinin-like genes and 36 previously unidentified peptidases. Genome analysis also reveals that P. gingivalis can metabolize a range of amino acids and generate a number of metabolic end products that are toxic to the human host or human gingival tissue and contribute to the development of periodontal disease.

This article is a series of personal narratives that captures the author's athletic experiences throughout her life, including swimming, horseback riding, basketball, and running. The author relates these experiences to her social development, exploring issues such as gender, sex role, norms, and body image.

This article, based upon a comparative analysis of televised coverage of the 'Final Four' of the women's and men's 1993 NCAA basketball tournaments, sheds light on some of the mechanisms through which an 'audience preference' is socially constructed for men's sports over women's sports. First, we examine the temporal framing of the women's and men's tournaments by the sports/media complex. Next, we present a comparative description of the visual and verbal televised presentation of the women's and men's games. On the basis of these comparisons, we argue that the sports/media complex actively constructs audiences that are likely to see the men's Final Four as a dramatic, historic event that they simply 'must' watch, while fans are likely to see the women's Final Four as a nonevent or, at best, as just another game. This, we argue, serves to situate viewers of men's sports at a nexus of power and pleasure, while simultaneously containing the potential challenge that female athleticism poses to hegemonic masculinity. Finally, we discuss, in light of socialist-feminist theory, the potentially contradictory outcomes of recent hints of increased televised coverage of women's basketball.

In vitro mutagenization of the cloned gene for L(+)-lactate dehydrogenase (LDH) from Streptococcus mutants yielded an Escherichia coli transformant expressing a thermolabile LDH activity. Introduction of the ldh(Ts) gene into S. mutants on a suicide vector to create a heterodiploid showing both wild-type and thermolabile CDH activities led to the isolation of self-recombinants, with only one ldh gene.