558 research outputs found

    Foraminifera On The Beach Of Malalayang Dua

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    Beach as one on the landform that reflects the work of hydro-oceanographic factors, generally in the form of loose sedimentary material. Loose sediment is a collection of organic and inorganic particles that accumulate widely and are irregular in shape. One example of organism in marine waters that contributes to the availability of organic particles in the beach landform is foraminifera. Foraminifera is a single-celled organism that has the ability to form shells from substances of CaCO3 which originate from itself or from the surrounding environment. This study was aimed to classify physical sediments on the Malalayang Dua beach according to the points of sediment sampling, and see how the composition of foraminifera in the beach area and analyze the presence of foraminifera in relation to the granulometry of beach sediments. From the result of the study, it is found that the composition of grain size of sediment on the beach of Malalayang Dua is different, in stasion 1A, 1B, 2A, and 2B the sediment were mostly composed by fine grains while in station 3A and 3B were of coarse-grained sediment. A number of a species of foraminifera (dead test) was found in the study, and the number of tests was highes in fine sediments compared to coarse sediment.Keywords : Beach Landform, Malalayang Dua Coast, Foraminifera ABSTRAKGisik sebagai salah satu bentuklahan yang merefleksikan kerja faktor-faktor hidro-oseanografi, umumnya berwujud material sedimen lepas. Sedimen lepas adalah kumpulan partikel organik dan anorganik yang terakumulasi secara luas dan bentuknya tidak beraturan. Salah satu organisme di perairan laut yang berkontribusi terhadap ketersediaan partikel organik di gisik adalah foraminifera. Foraminifera merupakan organisme bersel tunggal yang mempunyai kemampuan membentuk cangkang dari zat-zat CaCO3yang berasal dari dirinya sendiri atau dari lingkungan sekitarnya. Penelitian ini bertujuan untuk mengelompokkan sedimen gisik di pantai Malalayang Dua menurut titik-titik pengambilan sampel sedimen, dan melihat bagaimana komposisi foraminifera di kawasan gisik serta menganalisis keberadaan foraminifera dalam kaitannya dengan granulometri sedimen gisik. Dari hasil penelitian komposisi ukuran butir sedimen pada lahan gisik di pantai Malalayang Dua berbeda menurut stasiun yang ditetapkan, di ruang pantai ke arah Timur yaitu stasiun 1A, 1B, 2A, 2B komposisi sedimennya berukuran halus, sedangkan di ruang pantai ke arah Barat yaitu stasiun 3A dan 3B komposisi sedimennya berukuran kasar, komposisi sedimen di setiap stasiun gisik litoral dan sublitoral menampilkan adanya perbedaan tingkat kekasaran partikel sedimen. Dari hasil penelitian ditemukan 9 cangkang foraminifera. Pada komposisi sedimen gisik yang berukuran halus ditemukan jumlah cangkang foraminifera yang lebih banyak dibandingkan dengan gisik yang komposisi sedimen berukuran kasar.Kata kunci : Lahan Gisik, Pantai Malalalayang Dua, Foraminifer

    Measurements of total odd nitrogen (NOy) aboard MOZAIC in-service aircraft: instrument design, operation and performance

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    A small system for the unattended measurement of total odd nitrogen (NOy, i.e., the sum of NO and its atmospheric oxidation products) aboard civil in-service aircraft in the framework of MOZAIC is described. The instrument employs the detection of NO by its chemiluminescence with O-3 in combination with catalytic conversion of the other NOy compounds to NO at 300degreesC on a gold surface in the presence of H-2. The instrument has a sensitivity of 0.4-0.7 cps/ppt and is designed for unattended operation during 1-2 service cycles of the aircraft (400-800 flight hours). The total weight is 50 kg, including calibration system, compressed gases, mounting, and safety measures. The layout and inlet configuration are governed by requirements due to the certification for passenger aircraft. Laboratory tests are described regarding the conversion efficiency for NO2 and HNO3 (both > 98%). Interference by non-NOy species is <1% for CH3CN and NH3, <5 x 10(-5) % for N2O (corresponding to <0.2 ppt fake NOy from ambient N2O) and 100% for HCN. The time response of the instrument is <1 s (90% change) for NO2. The response for HNO3 is nonlinear: 20 s for 67%, 60 s for 80%, and 150 s for 90% response, respectively

    Demographic, Clinical, and Behavioral Determinants of 7-Year Weight Change Trajectories in Roux-en-Y Gastric Bypass Patients.

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    BACKGROUND: Weight change trajectories after weight-loss surgery may vary significantly. OBJECTIVES: This study evaluated the weight trajectories of Roux-en-Y gastric bypass (RYGB) patients and identified the distinct clinical, behavioral, and demographic features of patients by trajectory. SETTING: Data from 2918 RYGB patients from a comprehensive medical center between January 2004 and November 2016 were included. METHODS: This retrospective, observational study used data for RYGB patients up to year 7 postsurgery. Group-based trajectory models were fitted for percentage weight change. Variables evaluated by trajectory included age, sex, diagnoses, medications, smoking, presurgical body mass index, preoperative weight loss, and early postoperative weight loss. RESULTS: Of 3215 possible patients, 2918 (90.8%) were included (mean age = 46.2 ± 11.2 yr, body mass index = 46.9 ± 7.9 kg/m CONCLUSION: Select clinical, demographic, and behavioral factors may increase or decrease the chance for better weight loss after RYGB

    The influence of iron status and genetic polymorphisms in the HFE gene on the risk for postoperative complications after bariatric surgery: a prospective cohort study in 1,064 patients

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    <p>Abstract</p> <p>Background</p> <p>Gastric bypass surgery is a highly effective therapy for long-term weight loss in severely obese patients, but carries significant perioperative risks including infection, wound dehiscence, and leaks from staple breakdown. Iron status can affect immune function and wound healing, thus may influence peri-operative complications. Common mutations in the HFE gene, the gene responsible for the iron overload disorder hereditary hemochromatosis, may impact iron status.</p> <p>Methods</p> <p>We analyzed 1064 extremely obese Caucasian individuals who underwent open and laparoscopic Roux-n-Y gastric bypass surgery at the Geisinger Clinic. Serum iron, ferritin, transferrin, and iron binding capacity were measured pre-operatively. All patients had intra-operative liver biopsies and were genotyped for the C282Y and H63D mutations in the HFE gene. Associations between surgical complications and serum iron measures, HFE gene status, and liver iron histology were determined.</p> <p>Results</p> <p>We found that increased serum iron and transferrin saturation were present in patients with any post-operative complication, and that increased serum ferritin was also increased in patients with major complications. Increased serum transferrin saturation was also associated with wound complications in open RYGB, and transferrin saturation and ferritin with prolonged lengths of stay. The presence of 2 or more HFE mutations was associated with overall complications as well as wound complications in open RYGB. No differences were found in complication rates between those with stainable liver iron and those without.</p> <p>Conclusion</p> <p>Serum iron status and HFE genotype may be associated with complications following RYGB surgery in the extremely obese.</p

    Advancing the use of noncoding RNA in regulatory toxicology: Report of an ECETOC workshop

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    The European Centre for the Ecotoxicology and Toxicology of Chemicals (ECETOC) organised a workshop to discuss the state-of-the-art research on noncoding RNAs (ncRNAs) as biomarkers in regulatory toxicology and as analytical and therapeutic agents. There was agreement that ncRNA expression profiling data requires careful evaluation to determine the utility of specific ncRNAs as biomarkers. To advance the use of ncRNA in regulatory toxicology, the following research priorities were identified: (1) Conduct comprehensive literature reviews to identify possibly suitable ncRNAs and areas of toxicology where ncRNA expression profiling could address prevailing scientific deficiencies. (2) Develop consensus on how to conduct ncRNA expression profiling in a toxicological context. (3) Conduct experimental projects, including, e.g., rat (90-day) oral toxicity studies, to evaluate the toxicological relevance of the expression profiles of selected ncRNAs. Thereby, physiological ncRNA expression profiles should be established, including the biological variability of healthy individuals. To substantiate the relevance of key ncRNAs for cell homeostasis or pathogenesis, molecular events should be dose-dependently linked with substance-induced apical effects. Applying a holistic approach, knowledge on ncRNAs, 'omics and epigenetics technologies should be integrated into adverse outcome pathways to improve the understanding of the functional roles of ncRNAs within a regulatory context
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