703 research outputs found
A fifty year record of winter glacier melt events in southern Chile, 38°–42°S
Little is known about the frequency and potential mass balance impact of winter glacier melt events. In this study, daily atmospheric temperature soundings from the Puerto Montt radiosonde (41.43°S) are used to reconstruct winter melting events at the glacier equilibrium line altitude in the 38°–42°S region of southern Chile, between 1960 and 2010. The representativeness of the radiosonde temperatures to near-surface glacier temperatures is demonstrated using meteorological records from close to the equilibrium line on two glaciers in the region over five winters. Using a degree-day model we estimate an average of 0.28 m of melt and 21 melt days in the 15 June–15 September period each year, with high inter-annual variability. The majority of melt events are associated with midlatitude migratory high pressure systems crossing Chile and northwesterly flows, that force adiabatic compression and warm advection, respectively. There are no trends in the frequency or magnitude of melt events over the period of record, but the annual frequency of winter melt days shows a significant, although rather weak and probably non-linear, relationship to late winter and early spring values of a multivariate El Niño Southern Oscillation Index (MEI)
The Effect of Browse Species When Fed as a Supplement to Low Quality Native Grass Hay on Animal Performance
A pen trial was conducted to measure the impact of some browse species when fed as a supplement on the nitrogen (N) and dry matter intake of cattle receiving low quality native grass hay. There were 8 treatments consisting of a nil-supplement control treatment, a urea supplement control, a green oaten hay control and 5 treatment groups based on browse supplements (Albizia lebbeck, Carissa spp. and Bursaria spp.). Treatment effect on increased native pasture intake was related to the amount of supplementary nitrogen (N), such that there was a significant linear relationship between dry matter intake of native pasture and the intake of supplementary N. Similarly, there was a significant relationship between total dry matter intake and total intake of N
Controls on advance of tidewater glaciers: results from numerical modeling applied to Columbia Glacier
This is the published version, also available here: http://dx.doi.org/10.1029/2006JF000551.A one-dimensional numerical ice flow model is used to study the advance of a tidewater glacier into deep water. Starting with ice-free conditions, the model simulates glacier growth at higher elevations followed by advance on land to the head of the fjord. Once the terminus reaches a bed below sea level, calving is initiated. A series of simulations was carried out with various boundary conditions and parameterizations of the annual mass balance. The results suggest that irrespective of the calving criterion and accumulation rate in the catchment area, it is impossible for the glacier terminus to advance into deeper water (>300 m water depth) unless sedimentation at the glacier front is included. The advance of Columbia Glacier, Alaska, is reproduced by the model by including “conveyor belt” recycling of subglacial sediment and the formation of a sediment bank at the glacier terminus. Results indicate slow advance through the deep fjord and faster advance in shallow waters approaching the terminal moraine shoal and the mouth of the fjord
Having co-morbid cardiovascular disease at time of cancer diagnosis:Already one step behind when it comes to HRQoL?
Background The relation between cardiovascular disease (CVD) present at the time of cancer diagnosis and Health-Related Quality of Life (HRQoL) assessed years after cancer diagnosis has – to our knowledge – not been studied. The objective is, therefore, to examine the relation between co-morbid CVD at cancer diagnosis and HRQoL among cancer survivors diagnosed with colorectal, thyroid, prostate, endometrium, ovarian cancer, melanoma, (non-)Hodgkin lymphoma, chronic lymphocytic leukemia (CLL), or multiple myeloma (MM) in an exploratory population-based cross-sectional study. Material and methods Analyses were performed on combined data sets from the PROFILES and Netherlands Cancer Registry (NCR). Data on co-morbid CVD at cancer diagnosis was extracted from the NCR. HRQoL was measured via PROFILES at a median of 4.6 years after cancer diagnosis. General Linear Model Analyses were run for the total group of cancer survivors and for each malignancy. Results In total, 5930 cancer survivors (2281 colorectal, 280 thyroid, 1054 prostate, 177 endometrium, 389 ovarian cancer, 212 melanoma, 874 non-Hodgkin and 194 Hodgkin lymphoma, 242 CLL, and 227 MM survivors) were included. For the total group, survivors who had a CVD at cancer diagnosis (n = 1441, 23.4%) reported statistically significant and clinically important lower scores on global QoL and physical functioning and higher scores for dyspnea (p < .05) compared to those without CVD. Co-morbid CVD at cancer diagnosis was negatively related to global QoL, the five functional scales and the symptoms fatigue and dyspnea across most malignancies (i.e., colorectal, and prostate cancer, non-Hodgkin lymphoma, ovarium cancer, melanoma, and CLL). No significant relations were found among thyroid and endometrium cancer, Hodgkin lymphoma and MM survivors, likely due to small numbers. Conclusion In conclusion, co-morbid CVD at cancer diagnosis was negatively related to HRQoL, especially to global QoL, physical and role functioning, and the symptoms fatigue and dyspnea
Determination of uric acid in serum using isotachophoresis
An operational system is described for the isotachophoretic determination of uric acid in serum, making use of column coupling. The method has been compared with a standard enzymatic procedure. With the present technique small amounts of serum (ca. 3 μl) can be applied without any pretreatment. Urate recovery was 99.0–100.5%. Under the non-physiological measuring conditions used, 12–28% of control serum uric acid was bound to macromolecules of molecular weight exceeding 25,000. The day-to-day variations of the isotachophoretic procedure were smaller than those of the enzymatic method, whereas standard deviations were comparable. The isotachophoretic procedure is less influenced by certain metabolites
Associations between overweight and obesity and risk factors for cardiovascular disease and fatty liver in young offenders serving community orders
Purpose: The health of young offenders supervised in the community has not been previously studied. This paper describes the prevalence of overweight, obesity and obesity associated cardiovascular and hepatic risk factors in a sample of young offenders supervised in the community in New South Wales, Australia. Methods: During 2003-2005, 802 (85% male) young offenders took part in a comprehensive health survey that included direct measurement of height and weight as well as blood sampling. Results: The prevalence of combined overweight and obesity was 33.7% in boys and 35.3% in girls; both rates were higher than those of a comparable community sample. Cardiovascular risk factor prevalence was extremely high compared with other published studies, with over 90% of boys and almost 80% of girls having low levels of HDL cholesterol, and over 40% of both boys and girls having elevated LDL cholesterol. Risk factors for fatty liver disease were also prevalent with almost 15% of boys, and 30% of girls having raised ALT suggesting hepatic cell injury. Cardiovascular and fatty liver disease risk factors were significantly associated with overweight and obesity among boys, but not girls in this sample. Young people of Aboriginal or Torres Strait Islander decent were at no greater risk than the rest of the population. Conclusions: Young offenders are among the most disadvantaged people in Australian society and are particularly vulnerable to a range of health problems. The high prevalence of risk factors represents a substantial health burden for these young people in early adulthood. Timely intervention is required to address the complex health needs of this under-served population
Automatic Identification of Patients With Unexplained Left Ventricular Hypertrophy in Electronic Health Record Data to Improve Targeted Treatment and Family Screening
Background: Unexplained Left Ventricular Hypertrophy (ULVH) may be caused by genetic and non-genetic etiologies (e.g., sarcomere variants, cardiac amyloid, or Anderson-Fabry's disease). Identification of ULVH patients allows for early targeted treatment and family screening. Aim: To automatically identify patients with ULVH in electronic health record (EHR) data using two computer methods: text-mining and machine learning (ML). Methods: Adults with echocardiographic measurement of interventricular septum thickness (IVSt) were included. A text-mining algorithm was developed to identify patients with ULVH. An ML algorithm including a variety of clinical, ECG and echocardiographic data was trained and tested in an 80/20% split. Clinical diagnosis of ULVH was considered the gold standard. Misclassifications were reviewed by an experienced cardiologist. Sensitivity, specificity, positive, and negative likelihood ratios (LHR+ and LHR-) of both text-mining and ML were reported. Results: In total, 26,954 subjects (median age 61 years, 55% male) were included. ULVH was diagnosed in 204/26,954 (0.8%) patients, of which 56 had amyloidosis and two Anderson-Fabry Disease. Text-mining flagged 8,192 patients with possible ULVH, of whom 159 were true positives (sensitivity, specificity, LHR+, and LHR- of 0.78, 0.67, 2.36, and 0.33). Machine learning resulted in a sensitivity, specificity, LHR+, and LHR- of 0.32, 0.99, 32, and 0.68, respectively. Pivotal variables included IVSt, systolic blood pressure, and age. Conclusions: Automatic identification of patients with ULVH is possible with both Text-mining and ML. Text-mining may be a comprehensive scaffold but can be less specific than machine learning. Deployment of either method depends on existing infrastructures and clinical applications
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