528 research outputs found

    Pengaruh Lama Waktu Penyimpanan dan Penyinaran Cahayaterhadap Sitronelal Serta Uji Toksisitas dengan Menggunakan Metode Bslt(brine Shrimp Lethality Test)

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    Pada penelitian ini pengaruh lama waktu penyimpanan dan penyinaran cahaya pada sitronelal diuji untuk mengetahui Perubahan kandungan. Toksisitas sitronelal sebelum dan setelah penyimpanan dan penyinaran juga diuji menggunakan metode BSLT. Penyimpanan sitronelal dilakukan dalam botol vial Bening dan vial gelap yang disimpan dalam kotak kayu dengan perlakuan penyimpanan yang berbeda selama 4 minggu. Kotak yang pertama disinari lampu selama 24 jam (selanjutnya disebut kotak A), kotak kedua adalah kotak yang dua sisinya terbuat dari kasa selanjutnya disebut kotak B), dan kotak ketiga adalah kotak tertutup yang berwarna hitam (selanjutnya disebut kotak C). Analisis kandungan sitronelal sebelum dan sesudah penyimpanan menggunakan Kromatografi Gas-Spektrometer Massa (KG-SM). Hasil analisa KG-SM menunjukkan bahwa persen area berubah dari 45,29% menjadi 52,58% dan terdapat perbedaan jumlah puncak sampel setelah disimpan selama 2 minggu dalam kotak C dalam botol vial Bening. Sampel ini kemudian diuji toksisitasnya dengan BSLT. Hasil uji BSLT menunjukkan besarnya nilai LC50 sitronelal awal sebesar 71,1 ppm dan sebesar 132,79 ppm pada sitronelal setelah 2 minggu penyimpanan serta 324,97 ppm pada sitronelal setelah 4 minggu penyimpanan sehingga menunjukkan bahwa sitronelal dengan penyimpanan 2 minggu lebih toksik dibanding dengan sitronelal yang disimpan selama 4 mingg

    Oxygen declines and the shoaling of the hypoxic boundary in the California Current

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    6 páginas, 4 figuras, 1 tabla.We use hydrographic data from the California Cooperative Oceanic Fisheries Investigations program to explore the spatial and temporal variability of dissolved oxygen (DO) in the southern California Current System (CCS) over the period 1984–2006. Large declines in DO (up to 2.1 μmol/kg/y) have been observed throughout the domain, with the largest relative DO declines occurring below the thermocline (mean decrease of 21% at 300 m). Linear trends were significant (p < 0.05) at the majority of stations down to 500 m. The hypoxic boundary (∼60 μmol/kg) has shoaled by up to 90 m within portions of the southern CCS. The observed trends are consistent with advection of low-DO waters into the region, as well as decreased vertical oxygen transport following near-surface warming and increased stratification. Expansion of the oxygen minimum layer could lead to cascading effects on benthic and pelagic ecosystems, including habitat compression and community reorganization.We acknowledge the California Current Ecosystem Long-Term Ecosystem Research (CCE-LTER) project, supported by a grant from NSF (OCE-0417616), and grants from the NSF (OCE-0526640), the David and Lucile Packard Foundation and the NOAA Fisheries and the Environment (FATE) program.Peer reviewe

    Peritoneal carcinomatosis from gastric cancer: a multi-institutional study of 159 patients treated by cytoreductive surgery combined with perioperative intraperitoneal chemotherapy

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    BACKGROUND: Peritoneal carcinomatosis (PC) from gastric cancer has long been regarded a terminal disease with a short median survival. New locoregional therapeutic approaches combining cytoreductive surgery with perioperative intraperitoneal chemotherapy (PIC) have evolved and suggest improved survival. MATERIALS AND METHODS: A retrospective multicentric study was performed in French-speaking centers to evaluate the toxicity and the principal prognostic factors in order to identify the best indications. All patients had cytoreductive surgery and PIC: hyperthermic intraperitoneal chemotherapy (HIPEC) and/or early postoperative intraperitoneal chemotherapy (EPIC). RESULTS: The study included 159 patients from 15 institutions between February 1989 and August 2007. The median follow-up was 20.4 months. HIPEC was the PIC used for 150 procedures. Postoperative mortality and grade 3-4 morbidity rates were 6.5 and 27.8%, respectively. By multivariate analysis, the institution had a significant influence on toxicity. The overall median survival was 9.2 months and 1-, 3-, and 5-year survival rates were 43, 18, and 13%, respectively. The only independent prognostic indicator by multivariate analysis was the completeness of cytoreductive surgery. For patients treated by complete cytoreductive surgery, the median survival was 15 months with a 1-, 3-, and 5-year survival rate of 61, 30, and 23%, respectively. CONCLUSIONS: The therapeutic approach combining cytoreductive surgery with PIC for patients with gastric carcinomatosis may achieve long-term survival in a selected group of patients (limited and resectable PC). The high mortality rate underlines this necessarily strict selection that should be reserved to experienced institutions involved in the management of PC and gastric surgery

    The CAT Imaging Telescope for Very-High-Energy Gamma-Ray Astronomy

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    The CAT (Cherenkov Array at Themis) imaging telescope, equipped with a very-high-definition camera (546 fast phototubes with 0.12 degrees spacing surrounded by 54 larger tubes in two guard rings) started operation in Autumn 1996 on the site of the former solar plant Themis (France). Using the atmospheric Cherenkov technique, it detects and identifies very high energy gamma-rays in the range 250 GeV to a few tens of TeV. The instrument, which has detected three sources (Crab nebula, Mrk 421 and Mrk 501), is described in detail.Comment: 24 pages, 15 figures. submitted to Elsevier Preprin

    Yukawa Unification and the Superpartner Mass Scale

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    Naturalness in supersymmetry (SUSY) is under siege by increasingly stringent LHC constraints, but natural electroweak symmetry breaking still remains the most powerful motivation for superpartner masses within experimental reach. If naturalness is the wrong criterion then what determines the mass scale of the superpartners? We motivate supersymmetry by (1) gauge coupling unification, (2) dark matter, and (3) precision b-tau Yukawa unification. We show that for an LSP that is a bino-Higgsino admixture, these three requirements lead to an upper-bound on the stop and sbottom masses in the several TeV regime because the threshold correction to the bottom mass at the superpartner scale is required to have a particular size. For tan beta about 50, which is needed for t-b-tau unification, the stops must be lighter than 2.8 TeV when A_t has the opposite sign of the gluino mass, as is favored by renormalization group scaling. For lower values of tan beta, the top and bottom squarks must be even lighter. Yukawa unification plus dark matter implies that superpartners are likely in reach of the LHC, after the upgrade to 14 (or 13) TeV, independent of any considerations of naturalness. We present a model-independent, bottom-up analysis of the SUSY parameter space that is simultaneously consistent with Yukawa unification and the hint for m_h = 125 GeV. We study the flavor and dark matter phenomenology that accompanies this Yukawa unification. A large portion of the parameter space predicts that the branching fraction for B_s to mu^+ mu^- will be observed to be significantly lower than the SM value.Comment: 34 pages plus appendices, 20 figure

    Polarised Quark Distributions in the Nucleon from Semi-Inclusive Spin Asymmetries

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    We present a measurement of semi-inclusive spin asymmetries for positively and negatively charged hadrons from deep inelastic scattering of polarised muons on polarised protons and deuterons in the range 0.0030.0031 GeV2^2. Compared to our previous publication on this subject, with the new data the statistical errors have been reduced by nearly a factor of two. From these asymmetries and our inclusive spin asymmetries we determine the polarised quark distributions of valence quarks and non-strange sea quarks at Q2Q^2=10 GeV2^2. The polarised uu valence quark distribution, Δuv(x)\Delta u_v(x), is positive and the polarisation increases with xx. The polarised dd valence quark distribution, Δdv(x)\Delta d_v(x), is negative and the non-strange sea distribution, Δqˉ(x)\Delta \bar q(x), is consistent with zero over the measured range of xx. We find for the first moments 01Δuv(x)dx=0.77±0.10±0.08\int_0^1 \Delta u_v(x) dx = 0.77 \pm 0.10 \pm 0.08, 01Δdv(x)dx=0.52±0.14±0.09\int_0^1 \Delta d_v(x) dx = -0.52 \pm 0.14 \pm 0.09 and 01Δqˉ(x)dx=0.01±0.04±0.03\int_0^1 \Delta \bar q(x) dx= 0.01 \pm 0.04 \pm 0.03, where we assumed Δuˉ(x)=Δdˉ(x)\Delta \bar u(x) = \Delta \bar d(x). We also determine for the first time the second moments of the valence distributions 01xΔqv(x)dx\int_0^1 x \Delta q_v(x) dx.Comment: 17 page

    The mountainous Cretan dietary patterns and their relationship with cardiovascular risk factors: the Hellenic Isolated Cohorts MANOLIS study

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    Objective We carried out de novo recruitment of a population-based cohort (MANOLIS study) and describe the specific population, which displays interesting characteristics in terms of diet and health in old age, through deep phenotyping. Design Cross-sectional study where anthropometric, biochemical and clinical measurements were taken in addition to interview-based completion of an extensive questionnaire on health and lifestyle parameters. Dietary patterns were derived through principal component analysis based on a validated FFQ. Setting Geographically isolated Mylopotamos villages on Mount Idi, Crete, Greece. Subjects Adults (n 1553). Results Mean age of the participants was 61·6 years and 55·8 % were women. Of the population, 82·7 % were overweight or obese with a significantly different prevalence between overweight men and women (43·4 v. 34·7 %, P=0·002). The majority (70·6 %) of participants were married, while a larger proportion of women were widowed than men (27·8 v. 3·5 %, P<0·001). Smoking was more prevalent in men (38·7 v. 8·2 %, P<0·001), as 88·8% of women had never smoked. Four dietary patterns emerged as characteristic of the population; these were termed ‘local’, ‘high fat and sugar, ‘Greek café/tavern’ and ‘olive oil, fruits and vegetables’. Individuals more adherent to the local dietary pattern presented higher blood glucose (β=4·026, P<0·001). Similarly, individuals with higher compliance with the Greek café/tavern pattern had higher waist-to-hip ratio (β=0·012, P<0·001), blood pressure (β=1·015, P=0·005) and cholesterol (β=5·398, P<0·001). Conclusions Profiling of the MANOLIS elderly population identifies unique unhealthy dietary patterns that are associated with cardiometabolic indices

    Sociological stalking? Methods, ethics and power in longitudinal criminological research

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    Scholarship on criminal careers and desistance from crime employing longitudinal methodologies has paid scant attention to sociological and anthropological debates regarding epistemology, reflexivity and researcher positionality. This is surprising in light of a recent phenomenological turn in desistance research wherein (former) lawbreakers’ identity, reflexivity, and self-understanding have become central preoccupations. In this article I interrogate aspects of the methodological ‘underside’ (Gelsthorpe, 2007) of qualitative longitudinal research with criminalised women through an examination of the surveillant position of the researcher. Focusing on methods, ethics and power, I examine some contradictions of feminist concerns to ‘give women voice’ in research involving re-tracing an over-surveilled and highly stigmatised population. I reflect on the effects of researcher positionality through a conceptualisation of re-tracing methods as, at worst, a form of sociological stalking

    Intercalibration of the barrel electromagnetic calorimeter of the CMS experiment at start-up

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    Calibration of the relative response of the individual channels of the barrel electromagnetic calorimeter of the CMS detector was accomplished, before installation, with cosmic ray muons and test beams. One fourth of the calorimeter was exposed to a beam of high energy electrons and the relative calibration of the channels, the intercalibration, was found to be reproducible to a precision of about 0.3%. Additionally, data were collected with cosmic rays for the entire ECAL barrel during the commissioning phase. By comparing the intercalibration constants obtained with the electron beam data with those from the cosmic ray data, it is demonstrated that the latter provide an intercalibration precision of 1.5% over most of the barrel ECAL. The best intercalibration precision is expected to come from the analysis of events collected in situ during the LHC operation. Using data collected with both electrons and pion beams, several aspects of the intercalibration procedures based on electrons or neutral pions were investigated
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