33 research outputs found

    Dual isotope analyses indicate efficient processing of atmospheric nitrate by forested watersheds in the northeastern U.S.

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    Author Posting. © Springer, 2008. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Biogeochemistry 90 (2008): 15-27, doi:10.1007/s10533-008-9227-2.Nitrogen from atmospheric deposition serves as the dominant source of new nitrogen to forested ecosystems in the northeastern U.S.. By combining isotopic data obtained using the denitrifier method, with chemistry and hydrology measurements we determined the relative importance of sources and control mechanisms on nitrate (NO3-) export from five forested watersheds in the Connecticut River watershed. Microbially produced NO3- was the dominant source (82-100%) of NO3- to the sampled streams as indicated by the Ύ15N and Ύ18O of NO3-. Seasonal variations in the Ύ18O-NO3- in streamwater are controlled by shifting hydrology and temperature affects on biotic processing, resulting in a relative increase in unprocessed NO3- export during winter months. Mass balance estimates find that the unprocessed atmospherically derived NO3- stream flux represents less than 3% of the atmospherically delivered wet NO3- flux to the region. This suggests that despite chronically elevated nitrogen deposition these forests are not nitrogen saturated and are retaining, removing, and reprocessing the vast majority of NO3- delivered to them throughout the year. These results confirm previous work within Northeastern U.S. forests and extend observations to watersheds not dominated by a snow-melt driven hydrology. In contrast to previous work, unprocessed atmospherically derived NO3- export is associated with the period of high recharge and low biotic activity as opposed to spring snowmelt and other large runoff events.This work was funded by an EPA STAR Fellowship (FP-91637501-1) and a grant from QLF/The Sound Conservancy to RTB

    The co-occurrence of autistic and ADHD dimensions in adults: an etiological study in 17 770 twins

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    Autism spectrum disorder (ASD) and attention deficit/hyperactivity disorder (ADHD) often occur together. To obtain more insight in potential causes for the co-occurrence, this study examined the genetic and environmental etiology of the association between specific ASD and ADHD disorder dimensions. Self-reported data on ASD dimensions social and communication difficulties (ASDsc), and repetitive and restricted behavior and interests (ASDr), and ADHD dimensions inattention (IA), and hyperactivity/impulsivity (HI) were assessed in a community sample of 17 770 adult Swedish twins. Phenotypic, genetic and environmental associations between disorder dimensions were examined in a multivariate model, accounting for sex differences. ASDr showed the strongest associations with IA and HI in both sexes (rp 0.33 to 0.40). ASDsc also correlated moderately with IA (females rp 0.29 and males rp 0.35) but only modestly with HI (females rp 0.17 and males rp 0.20). Genetic correlations ranged from 0.22 to 0.64 and were strongest between ASDr and IA and HI. Sex differences were virtually absent. The ASDr dimension (reflecting restricted, repetitive and stereotyped patterns of behavior, interests and activities) showed the strongest association with dimensions of ADHD, on a phenotypic, genetic and environmental level. This study opens new avenues for molecular genetic research. As our findings demonstrated that genetic overlap between disorders is dimension-specific, future gene-finding studies on psychiatric comorbidity should focus on carefully selected genetically related dimensions of disorders

    EFEKTIVITAS PENGAWASAN UNIT KERJA ANTI FRAUD PADA BANK MUAMALAT INDONESIA

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    Perkembangan perbankan syari‟ah di Indonesia demikian pesat yang ditandai dengan berdirinya Bank Muamalat Indonesia. Perkembangan ini berimplikasi pada besarnya tantangan perbankan syari‟ah di Indonesia terutama dalam mempertahankan identitasnya sebagai perusahaan yang bergerak berlandaskan prinsip-prinsip syari‟ah. Sejak berdirinya perbankan syariah,berbagai kontroversi muncul dari masyarakat, masalah yang paling banyak disorot adalah pelekatan label syariah pada institusi keuangan Islam yang masih dianggap belum layak. Keraguan masyarakat tersebut seolah terjawab dengan munculnya kasus yang cukup menggemparkan yakni kasus fraud (tindak kecurangan) yang terjadi di lembaga syariah. Bank Muamalat Indonesia merupakan bank syari‟ah pertama yang muncul dengan gagasan bank murni syari‟ah. Akan tetapi, bank Muamalat Indonesia juga tak luput dari kasus fraud yang dilakukan oleh karyawan bank tersebut. Berdasarkan Laporan Tahunan BMI menyebutkan bahwa telah terjadi peningkatan kasus fraud dari tahun sebelumnya yang berjumlah 18 kasus menjadi 82 kasus pada tahun 2016. Padahal perusahaan yang menggunakan identitas syariah seharusnya dapat lebih meminimalisir bahkan meniadakan resiko terjadinya kasus fraud dengan adanya internal control perusahaan. Dari latar belakang tersebut, peneliti berusaha mendalami peran pengawasan Unit Kerja Anti Fraud dalam fraud preventive pada Bank Muamalat Indonesia. Penelitian ini merupakan penelitin pustaka yang bersifat deskriptif analisis dengan pendekatan kualitatif. Adapun sumber bahan hukum primer yang dipakai yaitu berdasarkan Laporan Tahunan Bank Muamalat Indonesia Tahun 2016. Sedangkan sumber bahan hukum sekunder berupa buku-buku, jurnal,karya ilmiah, artikel, terkait dengan strategi anti fraud perbankan syariah. Dari hasil penelitian dikemukakan bahwa peningkatan kasus fraud yang terjadi pada Bank Muamalat Indonesia disebabkan kurang efektifnya pengawasan Unit Kerja Anti Fraud. Hal ini dikarenakan kegiatan yang dilakukan selama tahun 2016 belum menujukkan adanya usaha preventif terhadap kasus fraud. Sedangkan pencegahan merupakan pilar penting dalam keefektivan sebuah pengawasan. Tujuan perusahaan dalam mencegah fraud dapat tercapai, jika fungsi pengawasan dilakukan sebelum terjadinya penyimpangan-penyimpangan sehingga lebih bersifat mencegah (prefentive control). Oleh karena itu, keefektivan pengawasan Unit Kerja Anti Fraud diharapkan dapat meminimalisir tindak kecurangan demi mewujudkan perusahaan yang patuh terhadap ketentuan syariah sesuai dengan identitas perusahaan. vii Usaha pencegahan terjadinya kasus pada Bank Muamalat Indonesia diharapkan dapat menjadi bukti terlaksananya tatakelola perusahaan (Good Corporate Governance) pada Bank Syari‟ah dengan baik. Hal ini berdasarkan dalam dalam perbankan syariah dikenal adanya prinsip-prinsip syariah yang mendukung bagi terlaksananya prinsip GCG yakni keharusan bagi subjek hukum termasuk bank untuk menerapkan prinsip kejujuran (shiddiq), edukasi kepada masyarakat (tabligh), kepercayaan (amanah), dan pengelolaan secara profesional (fathanah)

    Dominance of biologically produced nitrate in upland waters of Great Britain indicated by stable isotopes

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    Atmospheric deposition of nitrogen (N) compounds is the major source of anthropogenic N to most upland ecosystems, where leaching of nitrate (NO3−) into surface waters contributes to eutrophication and acidification as well as indicating an excess of N in the terrestrial catchment ecosystems. Natural abundance stable isotopes ratios, 15N/14N and 18O/16O (the “dual isotope” technique) have previously been used in biogeochemical studies of alpine and forested ecosystems to demonstrate that most of the NO3− in upland surface waters has been microbially produced. Here we present an application of the technique to four moorland catchments in the British uplands including a comparison of lakes and their stream inflows at two sites. The NO3− concentrations of bulk deposition and surface waters at three sites are very similar. While noting the constraints imposed by uncertainty in the precise ή18O value for microbial NO3−, however, we estimate that 79–98% of the annual mean NO3− has been microbially produced. Direct leaching of atmospheric NO3− is a minor component of catchment NO3− export, although greater than in many similar studies in forested watersheds. A greater proportion of atmospheric NO3− is seen in the two lake sites relative to their inflow streams, demonstrating the importance of direct NO3− deposition to lake surfaces in catchments where terrestrial ecosystems intercept a large proportion of deposited N. The dominance of microbial sources of NO3− in upland waters suggests that reduced and oxidised N deposition may have similar implications in terms of contributing to NO3− leaching
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