126 research outputs found
Fracture strength estimation of L3-L4 intervertebral disc using FEA
Mechanical stress and fracture analysis of the human lumbar intervertebral discs are important in assessing disorders related to lower back pain and ageing. Finite element modelling and simulation approaches assist in easier prediction of the disc behaviour under different load conditions. The causes of mechanical failure and morphological changes still remain partially speculative. The present study addresses the issue by developing a finite element model of an L3-L4 lumbar intervertebral disc subjected to different axial compressive loadings. The morphological deformations and stress concentration regions within the disc are analyzed and reported. A mathematical relation is established to estimate the breaking strength of an L3-L4 intervertebral disc, thus indicating the risk of disc failure based on the applied load
Model of LPG Refrigerator: A Literature Review
This work investigates the result of an experimental study carried out to determine the Coefficient of performance of domestic refrigerator when a propane-butane mixture is liquefied petroleum gas (LPG) which is available and comprises 56.4% butane, 24.4%propane, and 17.2% isobutene. This paper also presented an experimental investigation of COP by the effect of changing capillary tube length, capillary tube inner diameter and capillary coil diameter on the mass flow rate of refrigerant in an adiabatic helical capillary tube. Large amount of electricity supply is not available easily in large part of underdevelopment country like India. It will also prove to be an effective for remote area such as research sites, mines, & deserts where electricity is generally not available. The LPG is cheaper and possesses an environmental free in nature with no ozone depletion potential (ODP). Also LPG is available as a side product in local refineries. The results of the present work indicate the successful use of this propane-butane mixture as an alternative refrigerant to CFCs and HFCs in domestic refrigerator. It would include Experimental setup of working model and detailed observation of the LPG refrigerator and represents its application in refinery, hotel, chemical industries where requirement of LPG is more. Keywords: LPG refrigerator, domestic refrigerator, eco friendly refrigerants, Mixed Refrigerant
A Meta-analysis of Standard Versus Ultrasound-Assisted Catheter-Directed Thrombolysis in the Management of Acute Pulmonary Embolism
Background: Standard catheter-directed thrombolysis (SCDT) harnesses the therapeutic benefit of systemic thrombolytics while minimizing bleeding complications in patients presenting with pulmonary embolism (PE). Ultrasound-assisted catheter-directed thrombolysis (USAT) theoretically improves upon SCDT by disrupting fibrin and increasing the surface area exposed to thrombolytic agent. However, it is unclear if this translates into improved outcomes.
Methods: A systematic search of prior publications comparing SCDT and USAT in patients with intermediate or high-risk PE was conducted. Primary outcomes of interest were bleeding events, ICU and hospital length of stay. Secondary outcomes included changes in pulmonary artery systolic pressure (PASP), mean pulmonary artery pressure (mPAP), and right ventricle to left ventricle diameter (RV/LV) ratio. Studies that lacked comparison groups were excluded. Bias assessments were performed using the Cochrane tools for randomized and nonrandomized studies. Data was collated utilizing the Cochrane Review Manager software, and all analyses assumed random effects.
Results: Our search yielded 7 observational studies and 1 randomized control trial. The studies included a total of 543 patients who underwent either SCDT (n = 273) or USAT (n = 270) for intermediate or high-risk PE. The synthesized analysis showed no significant differences in bleeding between the groups. There were no differences in ICU or hospital lengths of stay, changes in PASP, or mPAP. Reductions in RV/LV ratio were greater with SCDT (mean difference, −0.16; 95% CI, −0.27 to −0.06; P =.003).
Conclusions: In comparison to SCDT, USAT did not result in improved clinical or hemodynamic outcomes in patients presenting with PE
Synthesis And Antimicrobial Screening of Novel Chalcone and Pyrazoline Molecules Bearing 4-(difluoromethoxy)-3-hydroxybenzaldehyde Nucleus
Elucidation of the structural and optical properties of metal cation (Na+, K+, and Bi3+) incorporated Cs2AgInCl6 double perovskite nanocrystals
This study presents series of direct band gap Pb-free double perovskite Cs2AgInxBi1−xCl6, Cs2NaxAg1−xInCl6:Bi and Cs2KxAg1−xInCl6:Bi nanocrystal systems [Cs2B′(I)B′′(III)Cl6] synthesised using a colloidal hot-injection route. The structural properties investigated using powder XRD, TEM, solid state NMR and materials modelling approaches demonstrate that the incorporation of K+ cations into the double perovskite nanocrystal structure occurs simultaneously on both the Cs (A) site and Ag (B′(I)) positions within a series of closely related cubic and monoclinic structures. As a result of defect passivation, significant improvements in the photoluminescence quantum yield (PLQY) of ∼4.7× and ∼1.8× are exhibited in comparison to the Cs2AgInxBi1−xCl6, and Cs2NaxAg1−xInCl6:Bi nanocrystal systems, respectively. Materials modelling using the Ab Initio Random Structure Search (AIRSS) method, and the GIPAW DFT calculation of the NMR parameters from the derived structural realisations, shows that K+ incorporation induces significant short-range structural disorder and multi-phase formation. This is highlighted by the large 133Cs and 39K chemical shift dispersion characterising the MAS NMR data. Density of States (DoS) calculations describing these AIRSS generated structures suggest that increasing ionic character and reduced structural rigidity are strongly correlated with A site substitution of the K+ cation into these cubic and monoclinic phases. The 39K MAS NMR data reveals that the increasing PLQY performance maps directly with the K+ incorporation into the cubic CsKyAg1−yInCl6 phase supporting B site occupancy which is observed to be maximized at a 60 ml% K+ incorporation level. However, additional evidence indicates that low level K+ substitution primarily targets A site occupancy in a surface passivation role. The improvement to the optical properties induced by K+ and Na+ incorporation is rationalised in terms of increased covalent character and structural rigidity associated with decreased Cs+, Na+ and K+ cation mobility, as evidenced by the large (∼2 orders of magnitude) variation in the 133Cs T1 data across each compositional range
Characterization of a Multistage Continuous MSMPR Crystallization Process assisted by Image Analysis of Elongated Crystals
This work demonstrates
how quantitative image analysis can assist
in the characterization of continuous crystallization processes and
in the proper selection of mathematical models for the early assessment
of crystal quality. An active pharmaceutical ingredient presenting
an elongated crystal habit was crystallized using two stirred tank
crystallizers in series. With image analysis of the crystallization
magma, the sources of crystal breakage in the crystallization cascade
were identified, and the impact on crystal habit was evaluated quantitatively.
As it is expected for particles presenting high aspect ratios, crystal
breakage preferentially occurs in the smallest plane, perpendicular
to the largest dimension. This phenomenon is hardly avoidable in downstream
production, but it can be accounted for with a design approach based
on the real crystal dimensions. The kinetic rate equations for nucleation
and crystal growth were determined based on crystal width, from which
a model for the accurate prediction of this dimension was applied.
The predicted crystal size distribution is consistent through a moderate
degree of crystal breakage during downstream processing
Data Mining in Health Care Sector: Literature Notes
© 2019 ACM. A standout amongst the most essential strides of the knowledge discovery in database KDD is data mining. Data mining is defined as a basic advance during the time spent learning discovery in databases in which understanding strategies are utilized in order to pattern discovery. Due to the huge amount of data available within the healthcare systems, data mining is important for the healthcare sector in the clinical and diagnosis diseases. However, data mining and healthcare organizations have developed some of dependable early discovery frameworks and different healthcare related frameworks from the clinical treatment and analysis information. The main motivation of this paper is to give a survey of data extraction in health care. In addition, the benefits and obstacles of the use of data extraction strategies in health care and therapeutic information have been thought
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