141 research outputs found
Alloys based on NiAl for high temperature applications
The NiAl alloys for potential high temperature applications were studied. Alloys were prepared by powder metallurgy techniques. Flow stress values at slow strain rates and high temperatures were measured. Some ternary alloying additions (Hf, Ta and Nb) were identified. The mechanism of strengthening in alloys containing these additions appears to be a form of particle dislocation interaction. The effects of grain size and stoichiometry in binary alloys are also presented
An Overview On Web Scraping Techniques And Tools
From the evolution of WWW, the scenario of internet user and data exchange is fastly changes. As common people join the internet and start to use it, lots of new techniques are promoted to boost up the network. At the same time, to enhance computers and network facility new technologies were introduces which results into automatically decreasing in cost of hardware and website�s related costs. Due to all these changes, large number of users are joined and use the internet facilities. Daily use of internet cose in to a tremendous data is available on internet. Business, academician, researchers all are share their advertisements, information on internet so that they can be connected to people fastly and easily. As a result of exchange, share and store data on internet, a new problem is arise that how to handle such data overload and how the user will get or access the best information in least efforts. To solve this issues, researcher spotout new technique called Web Scraping. Web scraping is very imperative technique which is used to generate structured data on the basis of available unstructured data on the web. Scaping generated structured data then stored in central database and analyze in spreadsheets. Traditional copy-and-paste, Text grapping and regular expression matching, HTTP programming, HTML parsing, DOM parsing, Webscraping software, Vertical aggregation platforms, Semantic annotation recognizing and Computer vision web-page analyzers are some of the common techniques used for data scraping. Previously most user uses the common copy-pest technique for gathering and analyzing data on the internet, but it is a tedious technique where lot of data copied by the user and store on computer files. As compared to this technique web scraping software is easiest scraping technique. Now a days, there are lots of software are available in the market for web scraping. Our paper is focused on the overview on the information extraction technique i.e. web scraping, different techniques of web scraping and some of the recent tools used for a web scraping
A review of issues and challenges
Determining the ages of young planetary surfaces relies on using populations
of small, often sub-km diameter impact craters due to the higher frequency at
which they form. Smaller craters however can be less reliable for estimating
ages as their size-frequency distribution is more susceptible to alteration
with debate as to whether they should be used at all. With the current
plethora of meter-scale resolution images acquired of the lunar and Martian
surfaces, small craters have been widely used to derive model ages to
establish the temporal relation of recent geologic events. In this review
paper, we discuss the many factors that make smaller craters particularly
challenging to use and should be taken into consideration when crater counts
are confined to small crater diameters. Establishing confidence in a model age
ultimately requires an understanding of the geologic context of the surface
being dated as reliability can vary considerably and limitations of the dating
technique should be considered in applying ages to any geologic
interpretation
A simple method of estimating folic acid absorption (a modified faecal excretion method)
This article does not have an abstract
Modification of secondary craters on the Martian South Polar Layered Deposits
Secondary crater fields are important stratigraphic markers that can shed light on resurfacing processes that have occurred since their formation. We examine the morphologies of secondary craters formed from the ejection of material from two large impacts on the Martian South Polar Layered Deposits (SPLD): McMurdo crater at 84.5°S, 0°W, and an unnamed impact at 80.8°S, 284°W. The morphologies of these secondary craters allow us to impose constraints on the modification history of the SPLD. We have quantified crater morphologies using data sets from the Mars Global Surveyor and Mars Odyssey missions. We find a complete lack of secondary craters smaller than 300 m in diameter in both crater fields, which implies that at least the upper 30 m of the deposits have been resurfaced since the time of these impacts. Secondary crater depth-to-diameter ratios are low (average of 0.016), indicating that significant degradation has occurred since their emplacement. We find that vertical resurfacing alone is not enough to explain the observed depth-to-diameter distribution and suggest that viscous relaxation of craters coupled with a small amount of vertical resurfacing best fits the data. In the McMurdo field, high depth-to-diameter craters are found preferentially on steeper terrain associated with scarps cutting through the secondary field. This observation suggests that crater modification exhibits a dependence on slope. We comment on possible mechanisms that may explain this observation. The morphologies of secondary craters on the SPLD point to modification processes without lunar parallel and not yet fully modeled for Mars
Influence of Voxelotor–hemoglobin complexes in the estimation of hemoglobin S levels by the current standard of care laboratory evaluation techniques
BackgroundSickle cell disease is an inherited disorder characterized by the presence of sickle hemoglobin (HbS). The process of Hb molecule polymerization is a pivotal step in the sickling process. Voxelotor, a recently approved novel therapeutic agent, is known to interfere with polymerization. We aim to study the impact of Voxelotor on Hb variants analysis using high performance liquid chromatography (HPLC).Material and methodsWe are reporting the impact of Voxelotor on Hb variants analysis using HPLC after an informed consent and medical research committee approval. Data was collected from eight patients who are enrolled in the GBT440-034OL study using electronic medical records, to evaluate the Hb levels, hemolytic markers and the clinical response.ResultsOur patients were well-balanced for gender, with a mean age of 31.1 years (19–50). Six patients showed a significant improvement in the Hb level, with reduced reticulocytes, bilirubin, LDH and an improved clinical outcome. Interestingly, these patients showed the appearance of a split band of Hb S and D on HPLC impacting significantly on HbS level. Two patients did not show any improvement on laboratory parameters, and no changes on their HPLC analysis.ConclusionsWe report here eight patients on Voxelotor therapy, six of which showed improved hemolytic markers and anemia and demonstrated the appearance of HbD peak on the HPLC chromatogram. Therefore, the absence of HbD on HPLC or other laboratory methods for estimating HbS in patients on Voxelotor therapy, gives the clinician a possible hint regarding the patient's compliance with the drug
Predicting risk factors for thromboembolic complications in patients with sickle cell anaemia - lessons learned for prophylaxis
Objective: To assess the clinical and laboratory predictors of venous thromboembolism (VTE) in patients with sickle cell anaemia (SCA) and its relationship to morbidity and mortality.
Methods: This retrospective case-control study analysed data from patients with SCA that experienced VTE compared with matched control patients with SCA but no VTE (2:1 ratio).
Results: A total of 102 patients with SCA were enrolled (68 cases with VTE and 34 controls). Amongst the 68 cases (median age, 29.5 years), 26 (38.2%) presented with isolated pulmonary embolism (PE). A higher prevalence of splenectomy (73.5% versus 35.3%) was observed in the cases compared with the controls. A significantly higher prevalence of central venous catheter (CVC) insertion (42.6% versus 8.8%) was observed in the cases compared with the controls. High white blood cell counts, serum lactic dehydrogenase (LDH), bilirubin and C-reactive protein (CRP) and low haemoglobin (Hb) and HbF were significant risk factors for VTE. Forty-two cases (61.8%) developed acute chest syndrome, 10 (14.7%) had a stroke and seven (10.3%) died.
Conclusions: VTE in patients with SCA has a high impact on morbidity and mortality. PE was the leading presentation of VTE, with CVC insertion, high LDH, bilirubin, CRP and white blood cell counts along with low Hb and HbF constituting other significant risk factors
Microbial competition for phosphorus limits the CO2 response of a mature forest
The capacity for terrestrial ecosystems to sequester additional carbon (C) with rising CO2 concentrations depends on soil nutrient availability1,2. Previous evidence suggested that mature forests growing on phosphorus (P)-deprived soils had limited capacity to sequester extra biomass under elevated CO2 (refs. 3–6), but uncertainty about ecosystem P cycling and its CO2 response represents a crucial bottleneck for mechanistic prediction of the land C sink under climate change7. Here, by compiling the first comprehensive P budget for a P-limited mature forest exposed to elevated CO2, we show a high likelihood that P captured by soil microorganisms constrains ecosystem P recycling and availability for plant uptake. Trees used P efficiently, but microbial pre-emption of mineralized soil P seemed to limit the capacity of trees for increased P uptake and assimilation under elevated CO2 and, therefore, their capacity to sequester extra C. Plant strategies to stimulate microbial P cycling and plant P uptake, such as increasing rhizosphere C release to soil, will probably be necessary for P-limited forests to increase C capture into new biomass. Our results identify the key mechanisms by which P availability limits CO2 fertilization of tree growth and will guide the development of Earth system models to predict future long-term C storage
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