96 research outputs found

    Termites in the woodwork

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    Termites eat and digest wood, but how do they do it? Combining advanced genomics and proteomics techniques, researchers have now shown that microbes found in the termites' hindguts possess just the right tools. Most animals, from insects to mammals, carry complex communities of microbes in their digestive tracts. In the case of wood-eating termites, these gut microbes are particularly important: they are thought to provide most of the capabilities needed for efficient digestion of wood, which is otherwise a largely inaccessible food source. They also help to compensate for the paucity of some nutrients in wood, for example by fixing atmospheric nitrogen, and they synthesize essential amino acids and other compounds for their hosts [1, 2]. Despite their importance, relatively little is known about gut microbes in termites. This is partly because gut microbes are often difficult to grow in pure culture (as is the case for most microbes sampled from natural environments). Furthermore, a single termite can harbor a very complex assemblage of hundreds of different microbial lineages, whose members may vary widely in terms of abundance and growth rates. Without access to cultivated strains, researchers have to rely on so-called 'cultivation-independent' molecular techniques to analyze such communities. A clever combination of these techniques has now been applied to a section of the termite hindgut, aiming to identify molecular tools used by the microbes in this compartment to degrade wood [3]. Here, we review the procedures and results of this study, and discuss insights into the biological system as well as implications for the generation of biofuels

    Quantitative Assessment of Nucleocytoplasmic Large DNA Virus and Host Interactions Predicted by Co-occurrence Analyses

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    Nucleocytoplasmic large DNA viruses (NCLDVs) are highly diverse and abundant in marine environments. However, the knowledge of their hosts is limited because only a few NCLDVs have been isolated so far. Taking advantage of the recent large-scale marine metagenomics census, in silico host prediction approaches are expected to fill the gap and further expand our knowledge of virus-host relationships for unknown NCLDVs. In this study, we built co-occurrence networks of NCLDVs and eukaryotic taxa to predict virus-host interactions using Tara Oceans sequencing data. Using the positive likelihood ratio to assess the performance of host prediction for NCLDVs, we benchmarked several co-occurrence approaches and demonstrated an increase in the odds ratio of predicting true positive relationships 4-fold compared to random host predictions. To further refine host predictions from high-dimensional co-occurrence networks, we developed a phylogeny-informed filtering method, Taxon Interaction Mapper, and showed it further improved the prediction performance by 12-fold. Finally, we inferred virophage-NCLDV networks to corroborate that co-occurrence approaches are effective for predicting interacting partners of NCLDVs in marine environments

    PEMBINAAN NARAPIDANA YANG MENGALAMI GANGGUAN JIWA DI DALAM LEMBAGA PEMASYARAKATAN

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    PEMBINAAN NARAPIDANA YANG MENGALAMI GANGGUAN JIWADI LEMBAGA PEMASYARAKATAN Agusriadi Dahlan Ali Suhaimi ABSTRAKLembaga Pemasyarakatan sebelumnya disebut Penjara adalah tempat orang-orang yang melakukan kriminalitas dan pelanggaran hukum lainnya agar mereka dapat menyadari kesalahannya dan mempertanggungjawabkan apa yang telah mereka perbuat. Hukuman yang mereka terima sebagai balasan yang setimpal terhadap perbuatan mereka, meskipun nilai-nilai kemanusiaan beserta hak asasinya kurang diperhatikan. Lembaga Pemasyarakatan merupakan tempat yang stressfull atau menekan yang dapat berpengaruh terhadap fisik dan kejiwaan (psikologi) seseorang ditambah kecemasan yang berlebihan sehingga muncul depresi yang mengakibatkan seseorang melakukan bunuh diri. Akibat stress melahirkan depresi dan depresi biasanya akan terjadi kegoncangan kejiwaan yang luar biasa yang dapat mengakibatkan seseorang menjadi tidak waras (gila). Undang-Undang No.12/1995 tentang Lembaga Pemasyarakatan maupun Peraturan Pemerintah No. 99 Tahun 2012 tentang Perubahan Kedua Atas Peraturan Pemerintah Nomor 32 Tahun 1999 tentang Syarat dan Tata Cara Pelaksanaan Hak Warga Binaan Pemasyarakatan tidak menjelaskan ketentuan terhadap narapidana yang gila di dalam lapas sebagaimana yang pernah terjadi di Lapas Kelas II-A Lambaro, Aceh Besar dan Rutan Klas I Tanjung Gusta, Medan. Selanjutnya yang bersangkutan dikirim ke Lapas Kelas Klass II-B Meulaboh tanggal 27 Januari 2014. Selama tujuh hari di Lapas Klass II-B Meulaboh Zabir bin Ilyas kemudian di titipkan di Rumah Sakit Jiwa Banda Aceh karena penyakitnya sudah mencapai stadium empat untuk mendapatkan perawatan dan penyembuhan kejiwaannya. Bagaimanakah pengaturan dan pembinaan terhadap narapidana yang mengalami gangguan kejiwaan dalam Lembaga Pemasyarakatan. Kemudian bagaimanakah kepastian hukum bagi narapidana yang sedang mengalami gangguan kejiwaan, dan bagaimana status hukum bagi narapidana yang sembuh dari gangguan kejiwaan. Penelitian dan pengkajian ini bertujuan untuk mengetahui pengaturan dan pembinaan terhadap narapidana yang mengalami gangguan kejiwaan dalam Lapas dan mengidentifikasi kepastian hukum bagi narapidana yang sedang mengalami gangguan kejiwaan serta mengetahui status hukum bagi narapidana yang sembuh dari gangguan kejiwaan.Metode yang digunakan adalah metode penelitian yuridis-normatif dengan menggunakan jenis penelitian deskriptis analisis dalam rangka untuk menemukan aturan hukum, prinsip-prinsip hukum, norma maupun doktrin-doktrin hukum dengan pendekatan undang-undang, kasus. Sumber data adalah data sekunder berupa bahan hukum primer, bahan hukum sekunder, dan bahan hukum tersier.Hasil penelitian menunjukkan bahwa Pengaturan tentang perawatan narapidana yang mengalami gangguan kejiwaan dalam Lembaga Pemasyarakatan di Indonesia belum diatur, baik dalam Undang-Undang Nomor 12 Tahun 1995 tentang Lembaga Pemasyarakatan maupun PP No. 99 Tahun 2012 tentang PP No. 99 Tahun 2012 tentang Perubahan Kedua Atas PP No.32 Tahun 1999 tentang Syarat dan Tata Cara Pelaksanaan Hak Warga Binaan Pemasyarakatan. Namun bila narapidana sakit atau gangguan kesehatan lainnya yang tidak termasuk gangguan kejiwaan ada aturan tentang perawatan medis. Adapun mengenai narapidana yang mengalami gangguan kejiwaan di Lembaga Pemasyarakatan di Indonesia hingga kini belum ada kepastian hukum karena kasus seperti ini sangat langka terjadi di Indonesia. Pihak otoritas hanya menggunakan hak diskresi yang dimilikinya untuk menyelesaikan kasus tersebut sebagaimana terjadi di Lapas Porong Surabaya. Tetapi di Aceh kasus ini baru pertama kali terjadi yang dialami Zabir bin Ilyas pada tahun 2014. Pimpinan Lapas memutuskan memasukkan Zabir bin Ilyas ke Rumah Sakit Jiwa Banda Aceh. Terkait status hukum narapidana yang sembuh dari gangguan kejiwaan masih tetap sebagai tersangka (ditahan). Tidak ada keringanan hukuman apalagi sampai dibebaskan sebelum masa hukuman habis dijalankan. Hingga kini tidak ada satupun aturan yang mengatur baik secara implisit maupun ekplisit yang mengatur tentang narapidana yang sembuh dari penyakit kejiwaan (gila).Disarankan kepada Pemerintah agar merevisi Undang-Undang Nomor 12 Tahun 1995 tentang Lembaga Pemasyarakatan dan memasukkan salah satu pasal yang mengatur mengenai narapidana yang mengalami gangguan kejiwaan di dalam Lembaga Pemasyarakatan. Agar terwujudnya kepastian hukum di Indonesia mengenai narapidana yang mengalami gangguan kejiwaan dalam lebaga pemasyarakatan untuk membuat regulasi legal baik berupa undang-undang khusus atau melalui Peraturan Pemerintah. Kemudian disarankan agar narapidana yang mengalami gangguan kejiwaan dalam Lembaga Pemasyarakatan dapat dibebaskan dan dikembalikan ke keluarganya atau dimasukkan ke rumah sakit jiwa hingga sembuh.Kata Kunci : Pembinaan, Narapidana, Gangguan Jiwa, Lembaga Pemasyarakatan.Banda Ace

    Microbial community functioning during plant litter decomposition

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    International audienceAbstract Microbial life in soil is fueled by dissolved organic matter (DOM) that leaches from the litter layer. It is well known that decomposer communities adapt to the available litter source, but it remains unclear if they functionally compete or synergistically address different litter types. Therefore, we decomposed beech, oak, pine and grass litter from two geologically distinct sites in a lab-scale decomposition experiment. We performed a correlative network analysis on the results of direct infusion HR-MS DOM analysis and cross-validated functional predictions from 16S rRNA gene amplicon sequencing and with DOM and metaproteomic analyses. Here we show that many functions are redundantly distributed within decomposer communities and that their relative expression is rapidly optimized to address litter-specific properties. However, community changes are likely forced by antagonistic mechanisms as we identified several natural antibiotics in DOM. As a consequence, the decomposer community is specializing towards the litter source and the state of decomposition (community divergence) but showing similar litter metabolomes (metabolome convergence). Our multi-omics-based results highlight that DOM not only fuels microbial life, but it additionally holds meta-metabolomic information on the functioning of ecosystems

    Predictive functional profiling of microbial communities using 16S rRNA marker gene sequences

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    Profiling phylogenetic marker genes, such as the 16S rRNA gene, is a key tool for studies of microbial communities but does not provide direct evidence of a community’s functional capabilities. Here we describe PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States), a computational approach to predict the functional composition of a metagenome using marker gene data and a database of reference genomes. PICRUSt uses an extended ancestral-state reconstruction algorithm to predict which gene families are present and then combines gene families to estimate the composite metagenome. Using 16S information, PICRUSt recaptures key findings from the Human Microbiome Project and accurately predicts the abundance of gene families in host-associated and environmental communities, with quantifiable uncertainty. Our results demonstrate that phylogeny and function are sufficiently linked that this ‘predictive metagenomic’ approach should provide useful insights into the thousands of uncultivated microbial communities for which only marker gene surveys are currently available

    Comparative metagenomic, phylogenetic and physiological analyses of soil microbial communities across nitrogen gradients

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    Terrestrial ecosystems are receiving elevated inputs of nitrogen (N) from anthropogenic sources and understanding how these increases in N availability affect soil microbial communities is critical for predicting the associated effects on belowground ecosystems. We used a suite of approaches to analyze the structure and functional characteristics of soil microbial communities from replicated plots in two long-term N fertilization experiments located in contrasting systems. Pyrosequencing-based analyses of 16S rRNA genes revealed no significant effects of N fertilization on bacterial diversity, but significant effects on community composition at both sites; copiotrophic taxa (including members of the Proteobacteria and Bacteroidetes phyla) typically increased in relative abundance in the high N plots, with oligotrophic taxa (mainly Acidobacteria) exhibiting the opposite pattern. Consistent with the phylogenetic shifts under N fertilization, shotgun metagenomic sequencing revealed increases in the relative abundances of genes associated with DNA/RNA replication, electron transport and protein metabolism, increases that could be resolved even with the shallow shotgun metagenomic sequencing conducted here (average of 75 000 reads per sample). We also observed shifts in the catabolic capabilities of the communities across the N gradients that were significantly correlated with the phylogenetic and metagenomic responses, indicating possible linkages between the structure and functioning of soil microbial communities. Overall, our results suggest that N fertilization may, directly or indirectly, induce a shift in the predominant microbial life-history strategies, favoring a more active, copiotrophic microbial community, a pattern that parallels the often observed replacement of K-selected with r-selected plant species with elevated N

    Bacterial Diversity in Oral Samples of Children in Niger with Acute Noma, Acute Necrotizing Gingivitis, and Healthy Controls

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    Noma is a devastating gangrenous disease that leads to severe facial disfigurement, but its cause remains unknown. It is associated with high morbidity and mortality and affects almost exclusively young children living in remote areas of developing countries, particularly in Africa. Several factors have been linked to the disease, including malnutrition, immune dysfunction, lack of oral hygiene, and lesions of the mucosal gingival barrier, particularly the presence of acute necrotizing gingivitis, and a potentially non-identified bacterial factor acting as a trigger for the disease. This study assessed the total bacterial diversity present in 69 oral samples of 55 children in Niger with or without acute noma or acute necrotizing gingivitis using culture-independent molecular methods. Analysis of bacterial composition and frequency showed that diseased and healthy site bacterial communities are composed of similar bacteria, but differ in the prevalence of a limited group of phylotypes. We failed to identify a causative infectious agent for noma or acute necrotizing gingivitis as the most plausible pathogens for both conditions were present also in sizeable numbers in healthy subjects. Most likely, the disease is initiated by a synergistic combination of several bacterial species, and not a single agent

    Machine learning in marine ecology: an overview of techniques and applications

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    Machine learning covers a large set of algorithms that can be trained to identify patterns in data. Thanks to the increase in the amount of data and computing power available, it has become pervasive across scientific disciplines. We first highlight why machine learning is needed in marine ecology. Then we provide a quick primer on machine learning techniques and vocabulary. We built a database of ∼1000 publications that implement such techniques to analyse marine ecology data. For various data types (images, optical spectra, acoustics, omics, geolocations, biogeochemical profiles, and satellite imagery), we present a historical perspective on applications that proved influential, can serve as templates for new work, or represent the diversity of approaches. Then, we illustrate how machine learning can be used to better understand ecological systems, by combining various sources of marine data. Through this coverage of the literature, we demonstrate an increase in the proportion of marine ecology studies that use machine learning, the pervasiveness of images as a data source, the dominance of machine learning for classification-type problems, and a shift towards deep learning for all data types. This overview is meant to guide researchers who wish to apply machine learning methods to their marine datasets.Machine learning in marine ecology: an overview of techniques and applicationspublishedVersio

    Microbial Co-occurrence Relationships in the Human Microbiome

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    The healthy microbiota show remarkable variability within and among individuals. In addition to external exposures, ecological relationships (both oppositional and symbiotic) between microbial inhabitants are important contributors to this variation. It is thus of interest to assess what relationships might exist among microbes and determine their underlying reasons. The initial Human Microbiome Project (HMP) cohort, comprising 239 individuals and 18 different microbial habitats, provides an unprecedented resource to detect, catalog, and analyze such relationships. Here, we applied an ensemble method based on multiple similarity measures in combination with generalized boosted linear models (GBLMs) to taxonomic marker (16S rRNA gene) profiles of this cohort, resulting in a global network of 3,005 significant co-occurrence and co-exclusion relationships between 197 clades occurring throughout the human microbiome. This network revealed strong niche specialization, with most microbial associations occurring within body sites and a number of accompanying inter-body site relationships. Microbial communities within the oropharynx grouped into three distinct habitats, which themselves showed no direct influence on the composition of the gut microbiota. Conversely, niches such as the vagina demonstrated little to no decomposition into region-specific interactions. Diverse mechanisms underlay individual interactions, with some such as the co-exclusion of Porphyromonaceae family members and Streptococcus in the subgingival plaque supported by known biochemical dependencies. These differences varied among broad phylogenetic groups as well, with the Bacilli and Fusobacteria, for example, both enriched for exclusion of taxa from other clades. Comparing phylogenetic versus functional similarities among bacteria, we show that dominant commensal taxa (such as Prevotellaceae and Bacteroides in the gut) often compete, while potential pathogens (e.g. Treponema and Prevotella in the dental plaque) are more likely to co-occur in complementary niches. This approach thus serves to open new opportunities for future targeted mechanistic studies of the microbial ecology of the human microbiome.National Institutes of Health (U.S.) (grant CA139193)Fonds Wetenschappelijk Onderzoek – VlaanderenJuvenile Diabetes Research Foundation InternationalNational Institutes of Health (U.S.) (grant NIH U54HG004969)Crohn's and Colitis Foundation of AmericaNational Science Foundation (U.S.) (NSF DBI-1053486)United States. Army Research Office (ARO W911NF-11-1-0473)National Institutes of Health (U.S.) (grant NIH 1R01HG005969

    Soil foraging animals alter the composition and co-occurrence of microbial communities in a desert shrubland

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    Animals that modify their physical environment by foraging in the soil can have dramatic effects on ecosystem functions and processes. We compared bacterial and fungal communities in the foraging pits created by bilbies and burrowing bettongs with undisturbed surface soils dominated by biocrusts. Bacterial communities were characterized by Actinobacteria and Alphaproteobacteria, and fungal communities by Lecanoromycetes and Archaeosporomycetes. The composition of bacterial or fungal communities was not observed to vary between loamy or sandy soils. There were no differences in richness of either bacterial or fungal operational taxonomic units (OTUs) in the soil of young or old foraging pits, or undisturbed soils. Although the bacterial assemblage did not vary among the three microsites, the composition of fungi in undisturbed soils was significantly different from that in old or young foraging pits. Network analysis indicated that a greater number of correlations between bacterial OTUs occurred in undisturbed soils and old pits, whereas a greater number of correlations between fungal OTUs occurred in undisturbed soils. Our study suggests that digging by soil-disturbing animals is likely to create successional shifts in soil microbial and fungal communities, leading to functional shifts associated with the decomposition of organic matter and the fixation of nitrogen. Given the primacy of organic matter decomposition in arid and semi-arid environments, the loss of native soil-foraging animals is likely to impair the ability of these systems to maintain key ecosystem processes such as the mineralization of nitrogen and the breakdown of organic matter, and to recover from disturbance
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