507 research outputs found
Effect of mattress deflection on CPR quality assessment for older children and adolescents
Appropriate chest compression (CC) depth is associated with improved CPR outcome. CCs provided in hospital are often conducted on a compliant mattress. The objective was to quantify the effect of mattress compression on the assessment of CPR quality in children.
Methods: A force and deflection sensor (FDS) was used during CPR in the Pediatric Intensive Care Unit and Emergency Department of a children's hospital. The sensor was interposed between the chest of the patient and hands of the rescuer and measured CC depth. Following CPR event, each event was reconstructed with a manikin and an identical mattress/backboard/patient configuration. CCs were performed using FDS on the sternum and a reference accelerometer attached to the spine of the manikin, providing a means to Calculate the mattress deflection.
Results: Twelve CPR events with 14,487 CC (11 patients, median age 14.9 years) were recorded and reconstructed: 9 on ICU beds (9296 CC), 3 on stretchers (5191 CC). Measured mean CC depth during CPR was 47 +/- 8 mm on ICU beds, and 45 +/- 7 mm on stretcher beds with overestimation of 13 +/- 4 mm and 4 +/- 1 mm, respectively, due to mattress compression. After adjusting for this, the proportion of CC that met the CPR guidelines decreased from 88.4 to 31.8% on ICU beds (p < 0.001), and 86.3 to 64.7% on stretcher (p < 0.001 The proportion of appropriate depth CC was significantly smaller on ICU beds (p < 0.001).
Conclusion: CC conducted on a non-rigid surface may not be deep enough. FDS may overestimate CC depth by 28% on ICU beds, and 10% on stretcher beds
Reactivity of blended SCMC for sustainable ternary cements
The Cement industry is responsible for huge CO2 emission; still, numerous efforts are being applied to increase the efficiency of cement plants. The CO2 emissions from cement production can also be reduced by replacing clinker content with supplementary cementitious materials (SCMs). Ternary cements are one of the most efficient ways to reduce the clinker content up to 50% without affecting the performance of cement. Before replacing clinker with any of the SCM’s, their reactivity must have to be studied properly. This paper will focus mainly on the reactivity of blended SCMs for ternary cements. Reactivity of different blends having calcined clay with limestone and fly ash with slag was studied in the presence of calcium hydroxide using isothermal calorimeter. The effect of different proportions of calcium hydroxide, accelerators, and temperature on reactivity was also studied. Additionally, the compressive strength of cement mortar cubes having 50% replacement of OPC was studied and further, the reactivity data of blends from calorimeter was compared with the compressive strength of mortars. It was observed that the compressive strength of calcined clay and limestone cement with different proportions was ranging from 38.17 to 32.70 MPa. Where as in the case of fly ash and slag cement having different proportions was ranging from 29.26 to 43.73 MPa. A reasonable good correlation was observed with the calorimeter energy data and strength
Effect of storage temperature and duration on sugar content and sensory acceptability of strawberry pulp
Experiment was conducted to study the effect of different treatments on preservation of strawberry pulp at ambient and low storage temperature condition. The samples were pasteurized at 100°C for 15 minutes (T1), sodium benzoate 250 ppm (T2) and sodium benzoate 500 ppm (T3). The respective samples were stored for two months at room (25±5°C) and low (7±2°C) temperature conditions and reducing sugars; total sugar and sensory evaluation were recorded at three days of interval period. The results showed that the total sugar (%) increased in pulp sample maximum in T6 (5.9%) and minimum in T1 (4.8%), the maximum value regarding reducing sugars was recorded in T6 (4.9%) and minimum in T1 (1.4%) after 60th days of storage. However, reducing sugars and total sugar decreased in the stored pulp at room temperature and spoiled completely on 18th day of storage. The acceptability of organoleptic score decrease with the duration of storage in both ambient and low temperature. Among different treatments, sodium benzoate @ 500 ppm was found most effective and maintained the qualitative characteristics of preserved pulp at low (7±2°C) temperature condition. In future, these experimental results may prove very useful for storage of strawberry pulp for longer duration in better quality
Performance analysis of anomalous photocatalytic activity of Cr-doped TiO2 nanoparticles [Cr(x)TiO2(1-x)]
We report the synthesis and characterisation of pristine and chromium (Cr) metal ion-doped titanium dioxide nanoparticles [Cr(x)TiO2(1-x)] to study the anomalous effect of Cr doping on the photocatalytic property of TiO2. The presence of dopants generates more number of recombination pairs and increases surface coverage sites which decreases photocatalytic activity. We study the structural morphology of the synthesised Cr(x)TiO2(1-x) samples using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy analysis. The effect of Cr3+ ions on the optical properties of TiO2 has been studied using various imaging and spectroscopic techniques. Further, the effect of doping of Cr on the photocatalytic activity of TiO2 has been analysed in detail. The concentration of Cr in TiO2 has been chosen as 0, 1, 5 and 10% by weight. It has been observed that the pristine TiO2 exhibits better photocatalytic activity as compared to Cr-doped TiO2 irrespective of the Cr concentration. This can be attributed to the fact that due to Cr doping in TiO2, the number of available adsorption sites for malachite green reduces which degrades its photocatalytic activity. It is also confirmed by photoluminescence (PL) and time-resolved photoluminescence spectroscopy. PL intensity increases, and lifetime decreases with increase in doping concentration. Radiative recombination of electron and hole pairs of Cr3+ in TiO2 degrades its photocatalytic activity. The degradation efficiency is found to be 96% in the case of pristine TiO2 which reduces to 12% when doped with x = 10% concentration of chromium. Therefore, it is observed that in comparison with Cr-doped TiO2, pristine TiO2 exhibits an improved photocatalytic activity which shows the anomalous effect of Cr doping on the photocatalytic property of TiO2
Geo-spatial technology application for prioritization of land resources in Udham Singh Nagar District of Uttarakhand, India
A loss of soil resources by prolific watersheds is a frequent problem confronting hydrologists and watershed managers. Soil erosion is a major factor in losses of soil. Different models are used for prediction of the amount of soil loss by erosion. In the present study, modelling using Revised Universal Soil Loss equation (RUSLE) is integrated with Remote Sensing (RS) and Geographical Information Systems (GIS) techniques and employed to estimate soil erosion and prioritization of watersheds of Udham Singh Nagar district of Uttarakhand, India. The results showed that Udham Singh Nagar district’s major portion (38.66%) is covered with agriculture land and only 17.57% area is covered with forest. Water-bodies have occupied 2.18% area of US Nagar district. A large variation has been noticed in case of built-up land which has been recorded as 5.71%. US Nagar has more agricultural land. Udham Singh Nagar is having plane topography hence the range of soil erosion is from 0 to 40 ton/ha/year. However, most region of Udham Singh Nagar district falls under the category of 0-2 ton/ha/year soil erosion. The value of soil losses in most of cases is less than 1 t/ha/yr except in case of 11 watersheds,where it is slightly higher than 1 t/ha/yr. Moreover, it has been concluded that major portion of Udham Singh Nagar districtwere slight prone category of soil erosion, and therefore, no major plan/activity is required for reducing soil losses. Only checking large amount of runoff and enhancing organic matter build up in the soil will suffice the purpose
Quantitative study of hydration of C3S and C2S by thermal analysis. Evolution and composition of C-S-H gels formed
This research is part of a European project (namely, CODICE project), main objective of which is modelling, at a multi-scale, the evolution of the mechanical performance of non-degraded and degraded cementitious matrices. For that, a series of experiments were planned with pure synthetic tri-calcium silicate (C3S) and bi-calcium silicate (C2S) (main components of the Portland cement clinker) to obtain different calcium–silicate–hydrate (C–S–H) gel structures during their hydration. The characterization of those C–S–H gels and matrices will provide experimental parameters for the validation of the multi-scale modelling scheme proposed. In this article, a quantitative method, based on thermal analyses, has been used for the determination of the chemical composition of the C–S–H gel together with the degree of hydration and quantitative evolution of all the components of the pastes. Besides, the microstructure and type of silicate tetrahedron and mean chain length (MCL) were studied by scanning electron microscopy (SEM) and 29Si magic-angle-spinning (MAS) NMR, respectively. The main results showed that the chemical compositions for the C–S–H gels have a CaO/SiO2 M ratio almost constant of 1.7 for both C3S and C2S compounds. Small differences were found in the gel water content: the H2O/SiO2 M ratio ranged from 2.9 ± 0.2 to 2.6 ± 0.2 for the C3S (decrease) and from 2.4 ± 0.2 to 3.2 ± 0.2 for the C2S (increase). The MCL values of the C–S–H gels, determined from 29Si MAS NMR, were 3.5 and 4 silicate tetrahedron, for the hydrated C3S and C2S, respectively, remaining almost constant at all hydration periods
Streptozotocin-Induced Early Thermal Hyperalgesia is independent of Glycemic State of Rats: Role of Transient Receptor Potential Vanilloid 1(TRPV1) and Inflammatory mediators
<p>Abstract</p> <p>Background</p> <p>Streptozotocin (STZ) is used as a common tool to induce diabetes and to study diabetes-induced complications including diabetic peripheral neuropathy (DPN). Previously, we have reported that STZ induces a direct effect on neurons through expression and function of the Transient receptor potential vanilloid 1 (TRPV1) channel in sensory neurons resulting in thermal hyperalgesia, even in non-diabetic STZ-treated mice. In the present study, we investigated the role of expression and function of TRPV1 in the central sensory nerve terminals in the spinal cord in STZ-induced hyperalgesia in rats.</p> <p>Results</p> <p>We found that a proportion of STZ-treated rats were normoglycemic but still exhibited thermal hyperalgesia and mechanical allodynia. Immunohistochemical data show that STZ treatment, irrespective of glycemic state of the animal, caused microglial activation and increased expression of TRPV1 in spinal dorsal horn. Further, there was a significant increase in the levels of pro-inflammatory mediators (IL-1β, IL-6 and TNF-α) in spinal cord tissue, irrespective of the glycemic state. Capsaicin-stimulated release of calcitonin gene related peptide (CGRP) was significantly higher in the spinal cord of STZ-treated animals. Intrathecal administration of resiniferatoxin (RTX), a potent TRPV1 agonist, significantly attenuated STZ-induced thermal hyperalgesia, but not mechanical allodynia. RTX treatment also prevented the increase in TRPV1-mediated neuropeptide release in the spinal cord tissue.</p> <p>Conclusions</p> <p>From these results, it is concluded that TRPV1 is an integral component of initiating and maintaining inflammatory thermal hyperalgesia, which can be alleviated by intrathecal administration of RTX. Further, the results suggest that enhanced expression and inflammation-induced sensitization of TRPV1 at the spinal cord may play a role in central sensitization in STZ-induced neuropathy.</p
Numerical benchmark campaign of cost action tu1404 – microstructural modelling
This paper presents the results of the numerical benchmark campaign on modelling of hydration and microstructure development of cementitious materials. This numerical benchmark was performed in the scope of COST Action TU1404 “Towards the next generation of standards for service life of cement-based materials and structures”. Seven modelling groups took part in the campaign applying different models for prediction of mechanical properties (elastic moduli or compressive strength) in cement pastes and mortars. The simulations were based on published experimental data. The experimental data (both input and results used for validation) were open to the participants. The purpose of the benchmark campaign was to identify the needs of different models in terms of input experimental data, verify predictive potential of the models and finally to provide reference cases for new models in the future. The results of the benchmark show that a relatively high scatter in the predictions can arise between different models, in particular at early ages (e.g. elastic Young’s modulus predicted at 1 d in the range 6-20 GPa), while it reduces at later age, providing relatively good agreement with experimental data. Even though the input data was based on a single experimental dataset, the large differences between the results of the different models were found to be caused by distinct assumed properties for the individual phases at the microstructural level, mainly because of the scatter in the nanoindentation-derived properties of the C-S-H phase.</jats:p
Identification of multiple root disease resistant wheat germplasm against cereal nematodes and dryland root rot and their validation in regions of economic importance
História da literatura portuguesa coordenada por Giulia Lanciani - primeiras páginas de um total pp. 7-108)História literária do século XVIII portuguêsGoverno de Portuga
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