1,542 research outputs found
Geochemical characteristics and structural setting of lithium–caesium–tantalum pegmatites of the Dorchap Dyke Swarm, northeast Victoria, Australia
The Dorchap Dyke Swarm hosts the first recorded occurrence of lithium–caesium–tantalum (LCT) pegmatites in Victoria, Australia. Syn-orogenic emplacement of pegmatite dykes occurred along a northwest-trending shear system during the Benambran Orogeny. Pegmatites are derived from fractionated melt associated with the Mount Wills Granite, which is an S-type, peraluminous granite originating from supracrustal melting of Ordovician sedimentary sequences. A distinct, eastward-oriented fractionation trend across the Dorchap Dyke Swarm has highlighted a 20 × 8 km highly fractionated zone in the northeastern Dorchap Range, which includes spodumene- and petalite-bearing pegmatites. A distinct pattern of elemental enrichment (P > Cs > Be > N
The Early Paleogene Succession at Tora, New Zealand; Stratigraphy and Paeloclimate: A Critical North Island Eocene Temperature Record and a Crucial Linkage Between the Depositional Settings of the Central and Southern East Coast Basin
This study has utilised the Mg/Ca paleothermometry method to provide a new, North Island reference of sea temperatures in the Southwest Pacific during a period of extreme global warming, referred to as the Early Eocene Climatic Optimum (EECO; ~53-50 Ma). This period of Earth’s history is of great interest as it represents the warmest climates of the Cenozoic. Importantly the climate dynamics of this period as simulated by computer models do not appear to match paleo-proxy data, specifically with regard to the latitudinal distribution of heat. Development of this paleoceanographic record involved detailed mapping of three sections in the Wairarapa region (41.506199 S, 175.517663 E) of New Zealand’s North Island. Three primary stratigraphic sections (Pukemuri, Awheaiti and Te Oroi Streams) were described and dated using foraminiferal and calcareous nannofossil biostratigraphy, with supplementary observations and measurements included from sections at Manurewa and Te Kaukau Points. These sediments are primarily siliciclastic sandstones and mudstones in composition, and sedimentary structures within these sections include turbidite sequences, channelisation and synsedimentary slumping, suggesting the EECO interval here is represented by sedimentation within a mid-bathyal submarine channel and fan environment. In contrast, the Early Paleocene Manurewa and Awhea Formations have previously been interpreted as a shallow, marginal marine environment which is at odds with benthic foraminiferal paleodepth indicators and trace fossil assemblages identified in this study.
Selected genera of planktic foraminifera were extracted from the EECO interval and paleo-water temperatures determined from Mg/Ca values measured by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA ICPMS). This method was selected as it allows specific targeting of analysis sites, enabling avoidance of contaminated and altered parts of the test. This method also provides simultaneous measurements of other trace elements (Al, Si, Ti, Mn, Zn, Sr, Ba) that can be used as a guide to preservation state of the test (for example, Al, Ti and Si are considered indicators of detrital contamination levels). Four foraminifera genera were selected as suitable paleotemperature indicators of separate components of the water column. Morozovella spp. and Acarinina spp. were selected for surface mixed layer paleotemperature estimates, Subbotina spp. for thermocline temperature values, and Cibicides spp. for bottom water temperature determinations.SEM images, combined with trace element data were used to parse the resulting Mg/Ca data and only those that met strict quality criterion, including low detrital contamination and lack of visual evidence for recrystalisation were used for temperature reconstruction. Planktic Mg/Ca data were converted to temperature using the relationship (Mg/Ca = [Mg/Casw-t]/[Mg/Casw-0] × 0.38 0.09 × T) and benthic Mg/Ca temperatures calculated using (Mg/Ca = [Mg/Casw-t]/[Mg/Casw-0] × 0.87 0.109 × T), each assuming an early Eocene seawater Mg/Ca value of 4.1 mol/mol. Calibrated Mg/Ca results show peak sea surface temperatures of 29°C for Morozovella and Acarinina in the East Coast Basin during the Early Eocene, with bottom water temperatures of 17°C obtained from Cibicides. These data are consistent with the high sea surface temperatures reconstructed by previous workers in the nearby Canterbury Basin. The data from this new reference point support the idea that the EECO was characterised by a lower, possibly absent latitudinal temperature gradient in the midlatitude Southwest Pacific, than numerical models suggest, indicating a fundamental gap in the knowledge of climate dynamics in conditions much warmer than today
In-depth critical analysis of complications following robot-assisted radical cystectomy with intracorporeal urinary diversion
Background:
Robot-assisted radical cystectomy with intracorporeal urinary diversion (iRARC) is an attractive option to open cystectomy, but the benefit in terms of improved outcomes is not established.
Objective:
To evaluate the early postoperative morbidity and mortality of patients undergoing iRARC and conduct a critical analysis of complications using standardised reporting criteria as stratified according to urinary diversion.
Design, setting, and participants:
A total of 134 patients underwent iRARC for bladder cancer at a single centre between June 2011 and July 2015.
Intervention:
Radical cystectomy with iRARC.
Outcome measurements and statistical analysis:
Patient demographics, pathologic data, and 90-d perioperative mortality and complications were recorded. Complications were reported according to the Clavien-Dindo (CD) classification and stratified according to urinary diversion type and either surgical or medical complications. The chi-square test and t test were used for categorical and continuous variables respectively. Multivariable logistic regression was performed on variables with significance in univariate analysis.
Results and limitations:
The 90-d all complication rate following ileal conduit and continent diversion was 68% and 82.4%, and major complications were 21.0% and 20.6% respectively. The 90-d mortality was 3% and 2.9% for ileal conduit and continent diversion patients, respectively. On multivariate analysis, the blood transfusion requirement was independently associated with major complications (p = 0.002) and all 30-d (p = 0.002) and 90-d (p = 0.012) major complications. Male patients were associated with 90-d major complications (p = 0.015). Critical analysis identified that surgical complications were responsible for 39.4% of all 90-d major complications. The incidence of surgical complications did not decline with increasing number of iRARC cases performed (p = 0.742, r = 0.31). Limitations of this study include its retrospective nature, limited sample size, and limited multivariate analysis due to the low number of major complications events.
Conclusions:
Although complications following iRARC are common, most are low grade. A critical analysis identified surgical complications as a cause of major complications. Addressing this issue could have a significant impact on lowering the morbidity associated with iRARC.
Patient summary:
We looked at the surgical outcomes in bladder cancer patients treated with minimally invasive robotic surgery. We found that surgical complications account for most major complications and previous surgical experience may be a confounding factor when interpreting results from a different centre even in a randomised trial setting
GIS-Based Expert Systems Model for Predicting Habitat Suitability of Blackside Dace
This study presents a GIS-based predictive habitat suitability model for the blackside dace, a federally-listed threatened species of the Upper Cumberland River basin in southeastern Kentucky. The model is a rules-based system which incorporates expert knowledge about habitat preferences for the species. The five habitat factors identified by experts and included in this model are stream gradient, canopy coverage, riparian vegetation type, riparian zone width, and stream order. Using GIS, the five habitat parameters were parameterized and combined across the entire stream network. Combinations were evaluated by blackside dace experts in terms of habitat suitability. The resulting model was tested against known blackside dace occurrences using locational modeling statistics. This analysis demonstrates success at identifying stream areas of both high and low likelihood of occurrences. Model results could be of particular usefulness to transportation planners in identifying sensitive areas in the landscape that may impact transportation planning
Benefits of robotic cystectomy with intracorporeal diversion for patients with low cardiorespiratory fitness: a prospective cohort study
Background:
Patients undergoing radical cystectomy have associated comorbidities resulting in reduced cardiorespiratory fitness. Preoperative cardiopulmonary exercise testing (CPET) measures including anaerobic threshold (AT) can predict major adverse events (MAE) and hospital length of stay (LOS) for patients undergoing open and robotic cystectomy with extracorporeal diversion. Our objective was to determine the relationship between CPET measures and outcome in patients undergoing robotic radical cystectomy and intracorporeal diversion (intracorporeal robotic assisted radical cystectomy [iRARC]).
Methods:
A single institution prospective cohort study in patients undergoing iRARC for muscle invasive and high-grade bladder cancer. Inclusion: patients undergoing standardised CPET before iRARC. Exclusions: patients not consenting to data collection. Data on CPET measures (AT, ventilatory equivalent for carbon dioxide [VE/VCO2] at AT, peak oxygen uptake [VO2]), and patient demographics prospectively collected. Outcome measurements included hospital LOS; 30-day MAE and 90-day mortality data, which were prospectively recorded. Descriptive and regression analyses were used to assess whether CPET measures were associated with or predicted outcomes.
Results:
From June 2011 to March 2015, 128 patients underwent radical cystectomy (open cystectomy, n = 17; iRARC, n = 111). A total of 82 patients who underwent iRARC and CPET and consented to participation were included. Median (interquartile range): age = 65 (58–73); body mass index = 27 (23–30); AT = 10.0 (9–11), Peak VO2 = 15.0 (13–18.5), VE/VCO2 (AT) = 33.0 (30–38). 30-day MAE = 14/111 (12.6%): death = 2, multiorgan failure = 2, abscess = 2, gastrointestinal = 2, renal = 6; 90-day mortality = 3/111 (2.7%). AT, peak VO2, and VE/VCO2 (at AT) were not significant predictors of 30-day MAE or LOS. The results are limited by the absence of control group undergoing open surgery.
Conclusions:
Poor cardiorespiratory fitness does not predict increased hospital LOS or MAEs in patients undergoing iRARC. Overall, MAE and LOS comparable with other series
The impact of dietary supplementation of arginine during gestation in a commercial swine herd: II. Offspring performance
Arginine (Arg) is an important amino acid of pig fetal development; however, whether Arg improves postnatal performance is ill-defined. Therefore, the influence of Arg supplementation at different gestational stages on offspring performance was evaluated in a commercial swine herd. Sows (n = 548) were allocated into 4, diet by stage of gestation treatments: Control (n = 143; 0% suppl. Arg), or dietary treatments supplemented with 1% L-Arg (free-base; Ajinomoto Animal Nutrition North America, Inc., Chicago, IL): from 15 to 45 d of gestation (n = 138; Early-Arg); 15 d of gestation to farrowing (n = 139; Full-Arg); and from day 85 of gestation to farrowing (n = 128; Late-Arg). All offspring were individually identified and weighed at birth; at weaning, a subset was selected for evaluation of carcass performance at market. All data were analyzed using birth weight (BiWt) and age as covariates. Wean weights (WW) and prewean (PW) ADG tended to increase (P = 0.06) in progeny from sows supplemented with Arg, as compared to progeny from Control sows. Preplanned contrast comparisons revealed an increased (P = 0.03) BiWt for pigs from sows receiving 1% L-Arg prior to day 45 of gestation (Early-Arg and Full-Arg; 1.38 kg/pig), as compared to pigs from sows not supplemented prior to day 45 of gestation (Control and Late-Arg; 1.34 kg/pig). No difference in BiWt was observed (1.36 kg/pig; P = 0.68) for Arg supplementation after day 85 of gestation (Full-Arg and Late-Arg), as compared to those not receiving Arg supplementation after day 85 (Control and Early-Arg); although WW and PW ADG were greater (P = 0.02), respectively. A 3.6% decrease (P = 0.05) in peak lean accretion ADG occurred when dams received 1% L-Arg prior to day 45 of gestation (Early-Arg and Full-Arg), however, no other significant differences were detected in finishing growth parameters or carcass characteristics (P ≥ 0.1). Pig mortality rates tended (P = 0.07) to decrease in progeny of dams supplemented Arg after day 85 (3.6%) compared to dams not provided additional Arg during late gestation (4.9%). Collectively, these data suggest that Arg provided during late gestation may improve WW and PW ADG, however, finishing performance was not affected. While Arg supplementation provided some moderate production benefits, further investigation is warranted to comprehensively understand the gestational timing and biological role of Arg supplementation during fetal and postnatal development in commercial production systems
The role of the genetic counsellor: a systematic review of research evidence
In Europe, genetic counsellors are employed in specialist genetic centres or other specialist units. According to the European Board of Medical Genetics, the genetic counsellor must fulfil a range of roles, including provision of information and facilitation of psychosocial adjustment of the client to their genetic status and situation. To evaluate the extent to which genetic counsellors fulfil their prescribed roles, we conducted a systematic review of the published relevant scientific evidence. We searched five relevant electronic databases (Medline, CINAHL, SocIndex, AMED and PsychInfo) using relevant search terms and handsearched four subject-specific journals for research-based papers published in English between 1 January 2000 and 30 June 2013. Of 419 potential papers identified initially, seven satisfied the inclusion criteria for the review. Themes derived from the thematic analysis of the data were: (i) rationale for genetic counsellors to provide care, (ii) appropriate roles and responsibilities and (iii) the types of conditions included in the genetic counsellor caseload. The findings of this systematic review indicate that where genetic counsellors are utilised in specialist genetic settings, they undertake a significant workload associated with direct patient care and this appears to be acceptable to patients. With the burden on genetic services, there is an argument for the increased use of genetic counsellors in countries where they are under-utilised. In addition, roles undertaken by genetic counsellors in specialist genetic settings could be adapted to integrate genetic counsellors into multi-disciplinary teams in other specialisms
NetPyNE, a tool for data-driven multiscale modeling of brain circuits
Biophysical modeling of neuronal networks helps to integrate and interpret rapidly growing and disparate experimental datasets at multiple scales. The NetPyNE tool (www.netpyne.org) provides both programmatic and graphical interfaces to develop data-driven multiscale network models in NEURON. NetPyNE clearly separates model parameters from implementation code. Users provide specifications at a high level via a standardized declarative language, for example connectivity rules, to create millions of cell-to-cell connections. NetPyNE then enables users to generate the NEURON network, run efficiently parallelized simulations, optimize and explore network parameters through automated batch runs, and use built-in functions for visualization and analysis – connectivity matrices, voltage traces, spike raster plots, local field potentials, and information theoretic measures. NetPyNE also facilitates model sharing by exporting and importing standardized formats (NeuroML and SONATA). NetPyNE is already being used to teach computational neuroscience students and by modelers to investigate brain regions and phenomena
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Sex differences in children’s toy preferences: A systematic review, meta-regression and meta-analysis
From an early age, most children choose to play with toys typed to their own gender. In order to identify variables that predict toy preference, we conducted a meta-analysis of observational studies of the free selection of toys by boys and girls aged between 1 and 8 years. From an initial pool of 1788 papers, 16 studies (787 boys and 813 girls) met our inclusion criteria. We found that boys played with male-typed toys more than girls did (Cohen's d = 1.03, p < .0001) and girls played with female-typed toys more than boys did (Cohen's d = −0.91, p < .0001). Meta-regression showed no significant effect of presence of an adult, study context, geographical location of the study, publication date, child's age, or the inclusion of gender-neutral toys. However, further analysis of data for boys and girls separately revealed that older boys played more with male-typed toys relative to female-typed toys than did younger boys (β = .68, p < .0001). Additionally, an effect of the length of time since study publication was found: girls played more with female-typed toys in earlier studies than in later studies (β = .70, p < .0001), whereas boys played more with male-typed toys (β = .46, p < .05) in earlier studies than in more recent studies. Boys also played with male-typed toys less when observed in the home than in a laboratory (β = −.46, p < .05). Findings are discussed in terms of possible contributions of environmental influences and age-related changes in boys' and girls' toy preference
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