711 research outputs found
Neonatal Intensive Care Units Nurses' Attitude Toward Advantages and Disadvantages of Open vs Closed Endotracheal Suction
Background: The vital issue of protecting the airway and maintaining ventilation in preterm infants makes tracheal suctioning an important procedure. The decision to use closed or open endotracheal suction method depends on the clinical status of infants and the nurses’ skills and preferences.
Objectives: The current study aimed to compare the two methods based on the perceptions of the nurses working in Neonatal Intensive Care Units (NICU).
Patients and Methods: A comparative-descriptive study carried out on 35 NICU nurses in Taleghani and Al-Zahra teaching hospitals in Tabriz, Iran, in 2013. Data were collected by self-administered questionnaire (13 Items). Data analysis, including t-test was performed using SPSS Ver. 13. A P ≤ 0.05 was considered statistically sigÂnificant.
Results: According to the nurses’ point of view, there are differences between characteristics of open and closed endotracheal suctioning methods (P < 0.001). By using closed endotracheal suction, the risk of traumatizing airway, developing pneumonia, increasing intracranial pressure, prolonging emergency suctioning, developing intra-ventricular hemorrhage, blood stream infection, physiological instability and lowering positive end-expiratory pressure (PEEP) are reduced. Meanwhile, lower cost, lower risk of extubation, comfort and easy washing procedure were reported as advantages of open suction.
Conclusion: Closed endotracheal suctioning was evaluated to be better than the open method in the preterm neonates. More studies, especially experimental and efficient cost analysis, are recommended
Effect of using different levels of pistachio by-products silage on composition and blood parameters of Holstein dairy cows
The goal of this research was to study about the effect of using pistachio hulls silage in cow's nutrition. The initial experiment was about the effect of several feed additives on chemical and fermentative characteristic of pistachio hulls silages. This experiment was designed with 5 treatments and 4 replications in each treatment in a complete randomized design. Additives for preparing pistachio hulls silage were in the sequence of 1.5% citrus pulp (in base of dry matter), 1.5% ground barley, 1.5% beet pulp, 1.5% molasses and one control treatment without any additives. Silages were sampled for chemical analysis and fermentative characteristics. Results of the analysis showed no significant variation between the treatments in respect of ash. In the second experiment, the application of pistachio hulls silage in the nutrition of lactating cows was studied. Eight lactating cows in one Latin square design experiment were used. Treatments included various amounts of pistachio hulls silage replaced with corn silage (in base of dry mater). The results show no significant variation between the treatments in milk, blood, rumen factors and digestibility factors that can show pistachio hulls silage that can be replaced with corn silage up to 15% (%dry matter) in dairy cows ration without any significant variation in cows production.Key words: Dairy cattle's, milk production, pistachio by-product, silage, tannin
An Investigation on Adoption of Socio-Culturally Based Teaching Strategies Among Iranian Clinical Nurse Educators
Background: In today’s complex healthcare environments, the traditional teaching strategies and learning models are unable to prepare learners to confront with rapid changes. Some education scholars believe that the teaching strategies based on socioculturally theory are more responsible and efficient.
Objectives: The present study was conducted to investigate socio-culturally-based teaching strategies being adopted or assigned by Iranian clinical nurse educators as high priorities.
Patients and Methods: A descriptive study was conducted on 38 nurse educators from two nursing and midwifery faculties in Tabriz and Urmia, Iran. Data were collected over a period of 2 months in 2010 using the Phillip’s Adoption Appraisal Instrument, developed by Bonk & Kim. The instrument items have been ranked on a 4-point Likert-type scale and ordered in 10 subscales. The data were analyzed using SPSS software version 13.0. The overall mean, standard deviation, and confidence interval 95% were calculated for each subscale to determine the rank distribution of subscales.
Results: All strategies were known as a moderate adoption (2.72 ± 0.44 of 4), however prioritizing in adoption of socio-culturally-based teaching strategies from clinical nurse educators’ viewpoints indicated that 60% of strategies were evaluated as the most adopted strategies, 10% as the least, and the other 30% in moderate mode.
Conclusions: Due to the importance of socio-culturally-based theory strategies in clinical settings and the moderate adoption of strategies from clinical nurse educators’ viewpoints,educational planners and policymakers should prepare required prepositions to progress the adoption and the usage of these strategies
Coordination of OLTC and Smart Inverters for Optimal Voltage Regulation of Unbalanced Distribution Networks
Photovoltaic (PV) smart inverters can improve the voltage profile of
distribution networks. A multi-objective optimization framework for
coordination of reactive power injection of smart inverters and tap operations
of on-load tap changers (OLTCs) for multi-phase unbalanced distribution systems
is proposed. The optimization objective is to minimize voltage deviations and
the number of tap operations simultaneously. A novel linearization method is
proposed to linearize power flow equations and to convexify the problem, which
guarantees convergence of the optimization and less computation costs. The
optimization is modeled and solved using mixed-integer linear programming
(MILP). The proposed method is validated against conventional rule-based
autonomous voltage regulation (AVR) on the highly-unbalanced modified IEEE 37
bus test system and a large California utility feeder. Simulation results show
that the proposed method accurately estimates feeder voltage, significantly
reduces voltage deviations, mitigates over-voltage problems, and reduces
voltage unbalance while eliminating unnecessary tap operations. The robustness
of the method is validated against various levels of forecast error. The
computational efficiency and scalability of the proposed approach are also
demonstrated through the simulations on the large utility feeder.Comment: Accepted for Electric Power Systems Research. arXiv admin note: text
overlap with arXiv:1901.0950
Potential nutritive value of some forage species used as ruminants feed in Iran
A study was conducted to determine rumen degradability (in sacco) of dry matter and in vitro gas production of the most important forage species grown in Iran, to compare forage species according to calculated degradation and in vitro gas production parameters, and to establish prediction equations for relative feed value (RFV) from gas production parameters. Thus, six forage species consisting of Lucerne, Eruca sativa, Crocus sativus, Cardaria draba, Setaria Spp., and Triticum aestivum forages were evaluated. Crude protein (CP) contents in the forages ranged from 139.60 to 246.30 g kg-1 DM. The neutral detergent fiber (NDF), acid detergent fiber (ADF) and organic matter (OM) were 273.30 to 596.60, 210.00 to 310.00, and 820.00 to 946.70 g kg-1 DM, respectively. The highest DM degradation and in vitro gas producton parameters were found for E. sativa. Also the relative feed value (RFV), relative forage quality (RFQ), dry mater intake and effective dry matter digestibility calculated for E. sativa was significantly (P < 0.05) higher than other forages. The variation of RFV explained by the gas production parameters ranged (R2) from 0.023 to 0.846. The gas production at 6, 24 and 48 h incubation times explained 0.836, 0.800 and 0.805 of variation of RFV, respectively. There was a negative correlation between in vitro gas production in different time incubation with NDF, ADF and a positive correlation between gas production parameters and CP content of forage species. The study shows that these forages relatively had a good nutritive value in comparison of Lucerne, and therefore, may serve as potential supplements for ruminants in Iran, and it seems that RFV index of six forage species such as used in this present study may be predicted from in vitro gas production parameters.Keywords: Forage species, in vitro gas production, in situ degradability, relative feed valu
Effect of Channel Boundary Conditions in Predicting Hydraulic Jump Characteristics using an ANFIS-Based Approach
Hydraulic jump is a phenomenon which is used to dissipate the kinetic energy of the flow and prevent scour below overflow spillways, chutes and sluices. This paper applies adaptive neuro-fuzzy inference system (ANFIS) as a Meta model approach to estimate hydraulic jump characteristics in channels with different bed conditions (i.e. channels with different shapes and appurtenances). In hydraulic jump characteristics modeling, different input combinations were developed and tested using 1700 experimental data. The obtained results indicated that the applied method has high capability in modeling hydraulic jump characteristics. It was observed that the developed models for expanding channel with a block performed more successful than other channels. For rectangular channels, it was found that the basin with rough bed led to better predictions compared to the basin with a step. In the prediction of jump length, the superior performance was obtained for the model with input combinations of Froude number and the relative height of jump. From the sensitivity analysis, it was induced that, Fr1 (upstream Froude number) is the most significant parameter in modeling process. Also comparison between ANFIS and semi-empirical equations indicated the great performance of the ANFIS
Effect of nanocurcumin and fish oil as natural anti-inflammatory compounds vs. glucocorticoids in a lipopolysaccharide inflammation model on Holstein calves’ health status
Curcumin (CUR) and fish oil (FO) are among the most well-known types of natural anti-inflammatory compounds. The aim of this study was to assess the effect of nanocurcumin and fish oil vs. glucocorticoids on Holstein calves' health status. A lipopolysaccharide (LPS) challenge (0.5 mu g kg(-1) BW) was used to induce an acute phase response. A total of 42 male Holstein calves were randomized into 7 groups: negative control (CON), positive control (LPS, injected once), 250 mg/kg BW per day fish oil + LPS (FO250), 350 mg/kg BW per day fish oil + LPS (FO350), 2 mg/kg BW per day nanocurcumin + LPS (NCUR2), 4 mg/kg BW per day nanocurcumin + LPS (NCUR4), and 0.3 mg/kg BW dexamethasone (injected once) + LPS (DEX). The duration of this experiment was 11 days, with application of the LPS challenge on day 8. Calves were weighed on days 0, 7, 9, 10, and 11 to record the average daily weight gain; diets offered and refused were recorded daily throughout the experiment. Blood collection and clinical scoring were conducted at successive time points until 72 h post LPS challenge. The data obtained also comprised rectal temperature (RT), respiratory rate (RR), heart rate (HR), concentrations of tumor necrosis factor-alpha (TNF-alpha), interleukin 6 (IL-6), serum amyloid A (SAA), and haptoglobin (Hp). This experiment could not uncover significant effects of LPS, FO, NCUR, and DEX on the area under the curve (AUC) of the RT, HR, and RR; in addition, there was no difference between FO and NCUR vs. LPS in sickness behavior, however, DEX group significantly recovered faster than others (P < 0.01). There was no significant difference between groups in dry matter intake (DMI) and average daily gain (ADG) during three days post LPS challenge. The concentrations of TNF-alpha, IL-6, and SAA were lower in the DEX group (P < 0.05). Finally, no effects of FO and NCUR on cytokines and acute phase proteins (APPs) could be observed in this study. In conclusion, supplementation of FO and NCUR was not able to impact the acute phase response (APR) in calves, as levels of inflammatory cytokines and APPs as well as sickness behavior remained unchanged. It seems that the anti-inflammatory effects of FO and CUR on APR, as has been observed for other animal species, do not manifest that clearly in calves
Low secondary electron yield engineered surface for electron cloud mitigation
Secondary electron yield (SEY or δ) limits the performance of a number of devices. Particularly, in high-energy charged particle accelerators, the beam-induced electron multipacting is one of the main sources of electron cloud (e-cloud) build up on the beam path; in radio frequency wave guides, the electron multipacting limits their lifetime and causes power loss; and in detectors, the secondary electrons define the signal background and reduce the sensitivity. The best solution would be a material with a low SEY coating and for many applications δ < 1 would be sufficient. We report on an alternative surface preparation to the ones that are currently advocated. Three commonly used materials in accelerator vacuum chambers (stainless steel, copper, and aluminium) were laser processed to create a highly regular surface topography. It is shown that this treatment reduces the SEY of the copper, aluminium, and stainless steel from δmax of 1.90, 2.55, and 2.25 to 1.12, 1.45, and 1.12, respectively. The δmax further reduced to 0.76-0.78 for all three treated metals after bombardment with 500 eV electrons to a dose between 3.5 × 10-3 and 2.0 × 10-2 C·mm-2
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