bluuebunny/crossref_metadata_2025_split huggingface dataset:
Formulating tightest bounds on causal effects in studies with unmeasured confounders
Authors: Kuroki Manabu , Cai Zhihong 
Published: September 2008

AbstractThis paper considers the problem of evaluating the causal effect of an exposure on an outcome in observational studies with both measured and unmeasured confounders between the exposure and the outcome. Under such a situation, MacLehose et al. (Epidemiology 2005; 16:548–555) applied linear programming optimization software to find the minimum and maximum possible values of the causal effect for specific numerical data. In this paper, we apply the symbolic Balke–Pearl linear programming method (Probabilistic counterfactuals: semantics, computation, and applications. Ph.D. Thesis, UCLA Cognitive Systems Laboratory, 1995; J. Amer. Statist. Assoc. 1997; 92:1172–1176) to derive the simple closed‐form expressions for the lower and upper bounds on causal effects under various assumptions of monotonicity. These universal bounds enable epidemiologists and medical researchers to assess causal effects from observed data with minimum computational effort, and they further shed light on the accuracy of the assessment. Copyright © 2008 John Wiley & Sons, Ltd.
Pericallosal lipoma associated with Pai syndrome: prenatal imaging findings
Authors: Chousta A. , Ville D. , James I. , Foray P. , Bisch C. , Depardon P. , Rudigoz R.‐C. , Guibaud L. 
Published: September 2008

AbstractPai syndrome is a rare disorder characterized by the association of a midline pericallosal lipoma, median cleft (palate or lip) and cutaneous polyps of the face. Only seven cases have been reported in the medical literature and we are not aware of any previously reported prenatally detected cases. In this article, we present the prenatal ultrasound and magnetic resonance imaging findings of a syndromic pericallosal lipoma with associated anomalies that led to the prenatal diagnosis of Pai syndrome. We underline the impact on parental counseling following prenatal detection of pericallosal lipoma. Copyright © 2008 ISUOG. Published by John Wiley & Sons, Ltd.
Characterization of basal seminal traits and reproductive endocrine profiles in North American river otters and Asian small‐clawed otters
Authors: Bateman Helen L. , Bond Jennifer B. , Campbell Mark , Barrie Michael , Riggs Gary , Snyder Barb , Swanson William F. 
Published: September 2008

AbstractIn this study, fecal samples were collected from 24 North American river (NARO) and 17 Asian small‐clawed otters (ASCO) for 6–36 months and semen collected seasonally from NARO males (n=4/season) via electroejaculation. Our main objectives were to: (1) characterize endocrine parameters by longitudinal monitoring of fecal hormone metabolites and (2) investigate semen collection and basal seminal traits in NARO. NARO demonstrated a distinct seasonality in the spring, with females having a monoestrual estrogen elevation lasting 15.33±1.98 (mean±SEM) days and males peaking in testosterone production for 25.50±7.51 days. Pregnancy was characterized by 7–9 months of basal fecal progesterone, presumably corresponding to embryonic diapause, followed by a rapid increase over the final 68–73 days to term. Pseudopregnancy exhibited a similar late winter progesterone peak of 68–72 days, which could not be differentiated from pregnancy. Geographic latitude possibly influenced the timing of increased testosterone in males and increased progesterone in pregnant/pseudopregnant females. In ASCO, monitoring of fecal estrogens did not allow consistent detection of peak values associated with behavioral estrus. Both pregnancy and pseudopregnancy were characterized by a moderate rise in fecal progesterone for 14–16 days postovulation followed by a marked increase. Total gestation length was 67–77 days compared with 62–84 days for pseudopregnancy. In NARO, optimal sperm recovery and quality occurred only in the spring, corresponding with seasonal increases in testicular volume and fecal testosterone. These findings represent the first comprehensive information on normative endocrine and seminal traits in freshwater otter species. Zoo Biol 28:107–126, 2009. © 2008 Wiley‐Liss, Inc.
Solution Strategies and Achievement in Dutch Complex Arithmetic: Latent Variable Modeling of Change
Authors: Hickendorff Marian , Heiser Willem J. , van Putten Cornelis M. , Verhelst Norman D. 
Published: September 2008

In the Netherlands, national assessments at the end of primary school (Grade 6) show a decline of achievement on problems of complex or written arithmetic over the last two decades. The present study aims at contributing to an explanation of the large achievement decrease on complex division, by investigating the strategies students used in solving the division problems in the two most recent assessments carried out in 1997 and in 2004. The students’ strategies were classified into four categories. A data set resulted with two types of repeated observations within students: the nominal strategies and the dichotomous achievement scores (correct/incorrect) on the items administered.It is argued that latent variable modeling methodology is appropriate to analyze these data. First, latent class analyses with year of assessment as a covariate were carried out on the multivariate nominal strategy variables. Results showed a shift from application of the traditional long division algorithm in 1997, to the less accurate strategy of stating an answer without writing down any notes or calculations in 2004, especially for boys. Second, explanatory IRT analyses showed that the three main strategies were significantly less accurate in 2004 than they were in 1997.
Long‐Chain Omega‐3 Polyunsaturated Fatty Acids in the Blood of Children and Adolescents with Juvenile Bipolar Disorder
Authors: Clayton Edward H. , Hanstock Tanya L. , Hirneth Stephen J. , Kable Colin J. , Garg Manohar L. , Hazell Philip L. 
Published: September 2008

AbstractReduced long‐chain omega‐3 polyunsaturated fatty acids (LCn‐3PUFA), including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), have been reported in adult patients suffering from depression and bipolar disorder (BD). LCn‐3PUFA status has not previously been examined in children and adolescents with BD compared with healthy controls. Fifteen children and adolescents (9–18 years, M ± SD = 14.4 ± 3.48) diagnosed with juvenile bipolar disorder (JBD) and fifteen healthy age and sex‐matched controls were assessed for dietary intake and fasting red blood cell (RBC) membrane concentrations of LCn‐3PUFA. Fatty acid concentrations were compared between participants diagnosed with JBD and controls after controlling for dietary intake. RBC membrane concentrations of EPA and DHA were not significantly lower in participants diagnosed with JBD compared with healthy controls (M ± sem EPA = 3.37 ± 0.26 vs. 3.69 ± 0.27 µg/mL, P = 0.458; M ± sem DHA = 22.08 ± 2.23 vs. 24.61 ± 2.38 µg/mL, P = 0.528) after controlling for intake. Red blood cell DHA was negatively (r = −0.55; P = 0.044) related to clinician ratings of depression. Although lower RBC concentrations of LCn‐3PUFA were explained by lower intakes in the current study, previous evidence has linked reduced LCn‐3PUFA to the aetiology of BD. As RBC DHA was also negatively related to symptoms of depression, a randomised placebo‐controlled study examining supplementation with LCn‐3PUFA as an adjunct to standard pharmacotherapy appears warranted in this patient population.
Circulating Levels of Lectin‐Like Oxidized Low‐Density Lipoprotein Receptor‐1 are Associated with Inflammatory Markers
Authors: Lubrano Valter , Del Turco Serena , Nicolini Giuseppina , Di Cecco Pietro , Basta Giuseppina 
Published: September 2008

AbstractLectin‐like oxidized‐low‐density lipoprotein receptor‐1 (LOX‐1) is increasingly linked to atherosclerotic plaque formation and the soluble form of this receptor may reflect activities of disease. We investigated the associations among levels of sLOX‐1, oxidized‐low‐density lipoprotein (ox‐LDL), cytokines and the extension of atherosclerosis in patients with coronary artery disease (CAD). Lipid, TNF‐α, IL‐6, C reactive protein (CRP), ox‐LDL, peroxy radical and sLOX‐1 levels were measured in 29 controls and 60 patients with CAD, 30 of which with one or two vessels involved (group 1), and 30 patients with three or four vessels involved (group 2). The serum levels of sLOX‐1 were significantly and progressively higher in group 1 [611 (346–1,313) pg/ml, median (interquartile range)] and in group 2 [2,143 (824–3,201) pg/ml] than in control subjects [268 (111–767) pg/ml]. LOX‐1 levels positively correlated with IL‐6 (r = 0.38, P = 0.0042), TNF‐α (r = 0.38, P = 0.0037), CRP levels (r = 0.32, P = 0.027) and age (r = 0.25, P = 0.048). In the multivariate analysis TNF‐α resulted the only independent determinant of LOX‐1 serum levels (β‐value = 0.304, P = 0.017). These findings suggest that sLOX‐1 levels are up‐regulated during CAD progression and are associated with inflammatory markers. The measurement of the circulating soluble form of this receptor may be potentially useful in predicting CAD progression in humans.
Sesamin Supplementation Increases White Muscle Docosahexaenoic Acid (DHA) Levels in Rainbow Trout (Oncorhynchus mykiss) Fed High Alpha‐Linolenic Acid (ALA) Containing Vegetable Oil: Metabolic Actions
Authors: Trattner Sofia , Kamal‐Eldin A. , Brännäs E. , Moazzami A. , Zlabek V. , Larsson P. , Ruyter B. , Gjøen T. , Pickova J. 
Published: September 2008

AbstractThe effects of including an equi‐mixture of sesamin and episesamin in fish diets based on vegetable oils of different fatty acid composition were examined. Sesamin/episesamin (hereafter named sesamin) was included at 0.58 g/100 g diet. The oil used in the feed was either a mixture of linseed and sunflower oils (6:4, by vol) or 100% linseed oil. Addition of sesamin increased the percentages of docosahexaenoic acid (DHA) in white muscle phospholipid and triacylglycerol fraction by up to 37% but the fatty acids in red muscle and liver were not affected. The expression of the peroxisome proliferator‐activated receptor PPARα was significantly down regulated in the liver of the fish fed sesamin and mixed oil diet (P < 0.05). Sesamin and episesamin were detected in liver and muscle tissues of the fish that had been fed sesamin. Fish fed sesamin had elevated levels of total cytochrome P450 (CYP) enzymes and EROD activity in the liver, indicating an induction of CYP1A in this tissue. Our conclusion was that supplementation of fish feed with sesamin increased the proportions of DHA in the white muscle.
Substrate Preferences of a Lysophosphatidylcholine Acyltransferase Highlight Its Role in Phospholipid Remodeling
Authors: Kazachkov Michael , Chen Qilin , Wang Liping , Zou Jitao 
Published: September 2008

AbstractAn important enzyme involved in phospholipid turnover is the acyl‐CoA: lysophosphatidylcholine acyltransferase (LPCAT). Here, we report characterization of a newly discovered human LPCAT (LPCAT3), which has distinct substrate preferences strikingly consistent with a role in phosphatidylcholine (PtdCho) remodeling and modulating fatty acid composition of PtdCho. LPCAT3 prefers lysophosphatidylcholine (lysoPtdCho) with saturated fatty acid at the sn‐1 position and exhibits acyl donor preference towards linoleoyl‐CoA and arachidonoyl‐CoA. Furthermore, LPCAT3 is active in mediating 1‐O‐alkyl‐sn‐glycero‐3‐phosphocholine acylation with long chain fatty acyl‐CoAs to generate 1‐O‐alkyl‐phosphatidylcholine, another very important constitute of mammalian membrane systems. These properties are precisely the known attributes of LPCAT previously ascribed to the isoform involved in Lands' cycle, and thus strongly suggest that LPCAT3 is involved in phospholipids remodeling to achieve appropriate membrane lipid fatty acid composition.
Influence of silence and attention on tinnitus perception
Authors: Knobel Keila Alessandra Baraldi , Sanchez Tanit Ganz 
Published: September 2008

ObjectiveThe purpose of this study was to study the effect of attention and sustained silence on the emergence of auditory phantom perception in normal‐hearing adults.Study DesignCross‐sectional survey.Subjects and MethodsWhile sitting in a sound booth, 66 volunteers (age range, 18–65; mean age, 37.3) performed 3 experiments of 5 minutes each, consecutively and randomly presented. Two deviated attention from auditory system (Hanoi and visual attention experiments), and 1 drove attention to the auditory system (auditory attention). After each experiment, participants were asked about their auditory and visual perception. No sound or light change was given at any moment.ResultsOf the participants, 19.7% experienced tinnitus during Hanoi, 45.5% during visual attention, and 68.2% during auditory attention experiment, with no significant differences for studied variables.ConclusionTinnitus‐like perceptions may occur in a non‐clinical population in a silent environment. Concomitant auditory attention plays an important role on the emergence of tinnitus.
Bones and words in 1870s New Zealand: the moa-hunter debate through actor networks
Authors: THODE SIMON 
Published: September 2008

AbstractThe paper describes an episode in New Zealand science commonly referred to as the moa-hunter debate. In the 1870s the geologist and curator of the Canterbury Museum Julius Haast put forward a proposal that a race distinct from the indigenous Maori hunted the giant flightless birds known as moa to extinction. James Hector, director of the New Zealand Geological Survey and manager of the New Zealand Institute, rejected this proposal and challenged Haast in what would become a bitter fight. Because moa remains in the form of semi-fossilized bones, eggshells and occasionally preserved feathers and skin were important in the debate, the paper will use the analytical method of actor-network theory (ANT) to reopen it. The paper thus provides an opportunity to study the strengths and weaknesses of ANT as a form of analysis. This analysis emphasizes a number of interesting points about the moa-hunter debate, including the ability of human actors to manipulate the meaning of common terms in order to create new theories, in this case Haast's theory of an earlier indigenous race in New Zealand. Though dismissed at the time, this was a belief that has lasted in alternative forms to the present.
Advertising cadavers in the republic of letters: anatomical publications in the early modern Netherlands
Authors: MARGÓCSY DÁNIEL 
Published: September 2008

AbstractThis paper sketches how late seventeenth-century Dutch anatomists used printed publications to advertise their anatomical preparations, inventions and instructional technologies to an international clientele. It focuses on anatomists Frederik Ruysch (1638–1732) and Lodewijk de Bils (1624–69), inventors of two separate anatomical preparation methods for preserving cadavers and body parts in a lifelike state for decades or centuries. Ruysch's and de Bils's publications functioned as an ‘advertisement’ for their preparations. These printed volumes informed potential customers that anatomical preparations were aesthetically pleasing and scientifically important but did not divulge the trade secrets of the method of production. Thanks to this strategy of non-disclosure and advertisement, de Bils and Ruysch could create a well-working monopoly market of anatomical preparations. The ‘advertising’ rhetorics of anatomical publications highlight the potential dangers of equating the growth of print culture with the development of an open system of knowledge exchange.
Effects ofn-3 fatty acids and acute exercise on endothelium-dependent vasorelaxation in healthy rat aorta
Authors: Thioub Sanéo , Mansourati Jacques , Corporeau Charlotte , Heylen Erwan , Delarue Jacques , Guerrero François 
Published: September 2008

The purpose of this study was to determine whethern-3 PUFA result in an effect on endothelial function that is in addition to that of acute exercise. For 4 weeks, male Sprague–Dawley rats were subjected to a diet based onn-3 PUFA or a standard diet. In each diet group, ten rats were submitted to an acute treadmill exercise while the remaining ten acted as sedentary controls. The running speed was progressively increased until the animals were exhausted. Endothelial function was then assessed by measuring isometric tension in rings of the thoracic aorta. In vessels precontracted with 0·1 μm-phenylephrine, responses to acetylcholine (ACh) were significantly improved following acute exercise in all diet groups. When PUFA supplementation was compared to the standard diet no significant difference was found in response to ACh, either at rest or after an acute exercise. Pretreatment of rings with Nω-nitro-l-arginine methyl esther (50 μm) inhibited the ACh-mediated vasorelaxation in all groups. Response to 10 μm-nifedipine, an L-type Ca2+channel antagonist, was similarly enhanced after acute exercise in both standard and PUFA diets. Furthermore, response to 0·01 μm-nifedipine was significantly higher after acute exercise only in the PUFA diet. In conclusion, in our ‘healthy’ rat model with ‘normal’ baseline endothelial function, acute exercise improves response to ACh while PUFA supplementation alone or in combination with acute exercise has no effect on endothelium-dependent vasorelaxation. However, PUFA may potentiate the acute exercise effect on smooth muscle cell relaxation via L-type Ca2+channel modifications.
Impact of energy deficit calculated by a predictive method on outcome in medical patients requiring prolonged acute mechanical ventilation
Authors: Faisy Christophe , Lerolle Nicolas , Dachraoui Fahmi , Savard Jean-François , Abboud Imad , Tadie Jean-Marc , Fagon Jean-Yves 
Published: September 2008

To assess energy balance in very sick medical patients requiring prolonged acute mechanical ventilation and its possible impact on outcome, we conducted an observational study of the first 14 d of intensive care unit (ICU) stay in thirty-eight consecutive adult patients intubated at least 7 d. Exclusive enteral nutrition (EN) was started within 24 h of ICU admission and progressively increased, in absence of gastrointestinal intolerance, to the recommended energy of 125·5 kJ/kg per d. Calculated energy balance was defined as energy delivered − resting energy expenditure estimated by a predictive method based on static and dynamic biometric parameters. Mean energy balance was − 5439 (sem222) kJ per d. EN was interrupted 23 % of the time and situations limiting feeding administration reached 64 % of survey time. ICU mortality was 72 %. Non-survivors had higher mean energy deficit than ICU survivors (P = 0·004). Multivariate analysis identified mean energy deficit as independently associated with ICU death (P = 0·02). Higher ICU mortality was observed with higher energy deficit (P = 0·003 comparing quartiles). Using receiver operating characteristic curve analysis, the best deficit threshold for predicting ICU mortality was 5021 kJ per d. Kaplan–Meier analysis showed that patients with mean energy deficit ≧5021 kJ per d had a higher ICU mortality rate than patients with lower mean energy deficit after the 14th ICU day (P = 0·01). The study suggests that large negative energy balance seems to be an independent determinant of ICU mortality in a very sick medical population requiring prolonged acute mechanical ventilation, especially when energy deficit exceeds 5021 kJ per d.
Dose-dependent effects of walnuts on motor and cognitive function in aged rats
Authors: Willis Lauren M. , Shukitt-Hale Barbara , Cheng Vivian , Joseph James A. 
Published: September 2008

Aged rats show decrements in performance on motor and cognitive tasks that require the use of spatial learning and memory. Previously we have shown that these deficits can be reversed by the polyphenolics in fruits and vegetables. Walnuts, which contain the n-3 fatty acids α-linolenic acid and linoleic acid, are a dietary source of polyphenols, antioxidants and lipids. Thus, the present study examined the effects of walnut supplementation on motor and cognitive ability in aged rats. Fischer 344 rats, aged 19 months, were fed a control, or a 2, 6 or 9 % walnut diet for 8 weeks before motor and cognitive testing. Results for the motor testing showed that the 2 % walnut diet improved performance on rod walking, while the 6 % walnut diet improved performance on the medium plank walk; the higher dose of the 9 % walnut diet did not improve psychomotor performance and on the large plank actually impaired performance. All of the walnut diets improved working memory in the Morris water maze, although the 9 % diet showed impaired reference memory. These findings show for the first time that moderate dietary walnut supplementation can improve cognitive and motor performance in aged rats.
Travertine deposits from along the South Tibetan Fault System near Nyalam, Tibet
Authors: ZENTMYER R. , MYROW P. M. , NEWELL D. L. 
Published: September 2008

AbstractA newly investigated travertine deposit in southern Tibet provides a window into Holocene hydrological, geomorphic and climatic processes near the boundary of the Tibetan Plateau and High Himalaya. Travertine, deposited as a result of the degassing of CO2-rich groundwater as it emerges on the Earth's surface, is in many cases formed along the trace of major crustal-scale faults in primarily extensional tectonic regimes. A travertine platform measuring roughly 1 km by 0.5 km exists near the town of Nyalam in southern Tibet along a major Himalayan down-to-the-N normal fault, the South Tibetan Fault System. A wide variety of travertine depositional textures and features are recorded in the platform on a series of terraces. Active travertine deposition was observed from spring mounds and seeps along the base of the platform at the modern river level. Palaeotemperatures of spring water, calculated from δ18O of the travertine, range from 9 to 25 °C, which closely matches the temperatures recorded from modern springs in the area. A complex geomorphological landscape records interaction between growing alluvial fans, travertine accumulation, and a rapidly down-cutting river with associated fluvial terraces. River incision was contemporaneous with travertine deposition, as indicated by cemented fluvial river gravel layers interbedded with travertine. High 87Sr/86Sr ratios in the travertine (mean of 0.7168) indicate subsurface fluid interaction with radiogenic crystalline rocks of the underlying Greater Himalaya. Uranium-series ages of the travertine platform range from 5400 a (±950 a) to 11600 a (±1000 a), and indicate a younging progression from higher terraces near the valley wall to lower terraces at present-day river level. Travertine that overlies a river gravel terrace 18 m above river level formed at 11600 a. This date yields a local incision rate of 1.6 mm a−1, consistent with estimated fluvial incision rates in the High Himalaya. The range of our U-series ages coincides with an interval of higher precipitation associated with greater intensity of the Indian monsoon, which led to elevated spring discharge and carbonate precipitation in this part of the High Himalayas.