294 research outputs found
How does split announcement affect stock liquidity? Evidence from Bursa Malaysia
Β© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This study examines the impact of stock splits on stock liquidity in Bursa Malaysia from 2004β2018. The study uses event study methodology and investigates liquidity changes, the role of liquidity, and the relationship between abnormal returns and liquidity as well. We found a significant liquidity improvement on the splits announcement, announcement of book closing date and split execution date (Ex-date), while it declined after the split Ex-date. The findings also indicate that firms with a low-level liquidity prior to split announcements experienced an increase in liquidity after Ex-date. Using panel data analysis, we find that the fixed effect model is more appropriate than the pooled OLS, and the abnormal announcement returns are driven by stock liquidity
Support in Clinical Settings as Perceived by Nursing Students in Iran: A Qualitative Study
Background: Although support is one of the most substantial needs of nursing students during clinical education, it is not clearly defined in the literature.
Objectives: The current study aimed to explore the concept of support in clinical settings as perceived by nursing students.
Materials and Methods: A qualitative content analysis was used to explore the meaning of student support in clinical settings. A purposive sampling with maximum variation was used to select the participants among bachelor nursing students in the nursing school of Babol University of Medical Sciences in the north of Iran. Semi-structured interviews were conducted to gather the perceptions and experiences of seventeen nursing students. Conventional content analysis was applied to analyze the data.
Results: In the current study, the main theme, nurturance, was emerged with seven subthemes of humanistic behavior with the student, respectful communication with students, accepting the student in the clinical setting, sustaining confidence, need based supervision, accepting the profession in the society and empowerment.
Conclusions: Nursing students support in the clinical education requires a nurturing care; a care that leads to the sense of worthiness and respectability in students and contributes to the improvement of their clinical abilities
Investigation on microstructure and oxidation behavior of Cr-modified aluminide coating on Ξ³-TiAl alloys
Microstructure and oxidation behavior of aluminide coating has been investigated. The layers were examined by optical microscopy, scanning electron microscopy (SEM) equipped with EDS and X-ray diffraction method. The isothermal oxidation behaviors of samples were investigated at 950Β°C for 200 h. The results indicated that TiAlβ were formed on substrate. In addition, aluminide coating improved the oxidation resistance of Ξ³-TiAl alloys by forming a protective alumina scale. Moreover, during oxidation treatment the interdiffusion of TiAlβ layer with Ξ³-TiAl substrate results in depletion of aluminum in the TiAlβ layer and growth of TiAlβ layer. After oxidation treatment the coating layer maintained a microstructure with phases including TiAlβ, TiAlβ and AlβOβ.ΠΠΎΡΠ»ΡΠ΄ΠΆΠ΅Π½ΠΎ ΠΌΡΠΊΡΠΎΡΡΡΡΠΊΡΡΡΡ Π°Π»ΡΠΌΡΠ½ΡΠ΄Π½ΠΎΠ³ΠΎ ΠΏΠΎΠΊΡΠΈΠ²Ρ ΡΠ° ΠΉΠΎΠ³ΠΎ ΠΏΠΎΠ²Π΅Π΄ΡΠ½ΠΊΡ ΠΏΡΠ΄ ΡΠ°Ρ Π²ΠΈΡΠΎΠΊΠΎΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ½ΠΎΠ³ΠΎ ΠΎΠΊΠΈΡΠ»Π΅Π½Π½Ρ. Π¨Π°ΡΠΈ Π°Π»ΡΠΌΡΠ½ΡΠ΄ΡΠ² ΡΠΈΡΠ°Π½Ρ Π²ΠΈΠ²ΡΠ°Π»ΠΈ Π·Π° Π΄ΠΎΠΏΠΎΠΌΠΎΠ³ΠΎΡ ΠΎΠΏΡΠΈΡΠ½ΠΎΡ ΠΌΡΠΊΡΠΎΡΠΊΠΎΠΏΡΡ, ΡΠΊΠ°Π½ΡΠ²Π½ΠΎΡ Π΅Π»Π΅ΠΊΡΡΠΎΠ½Π½ΠΎΡ ΠΌΡΠΊΡΠΎΡΠΊΠΎΠΏΡΡ (SΠΠ) Π· Π²ΠΈΠΊΠΎΡΠΈΡΡΠ°Π½Π½ΡΠΌ Π΄ΠΈΡΠΏΠ΅ΡΡΠ½ΠΎΠ³ΠΎ ΡΠ΅Π½ΡΠ³Π΅Π½ΠΎΡΠΏΠ΅ΠΊΡΡΠΎΠΌΠ΅ΡΡΠ° (EDS) ΡΠ° ΡΠ΅Π½ΡΠ³Π΅Π½ΡΠ²ΡΡΠΊΠΈΠΌ Π΄ΠΈΡΡΠ°ΠΊΡΡΠΉΠ½ΠΈΠΌ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ. ΠΠΈΠΏΡΠΎΠ±ΠΎΠ²ΡΠ²Π°Π½Π½Ρ ΠΏΡΠΎΠ²ΠΎΠ΄ΠΈΠ»ΠΈ ΠΏΡΠΈ 950Β°C Π²ΠΏΡΠΎΠ΄ΠΎΠ²ΠΆ 200 h. ΠΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΎ, ΡΠΎ Π½Π° ΠΏΡΠ΄ΠΊΠ»Π°Π΄ΡΡ Π· ΡΠΈΡΠ°Π½ΠΎΠ²ΠΎΠ³ΠΎ ΡΠΏΠ»Π°Π²Ρ ΡΡΠ²ΠΎΡΠΈΠ²ΡΡ TiAlβ. ΠΠΎΠΊΡΠΈΠ² Π· Π°Π»ΡΠΌΡΠ½ΡΠ΄Ρ ΡΠΈΡΠ°Π½Ρ ΠΏΠΎΠΊΡΠ°ΡΡΡ ΡΡΡΠΉΠΊΡΡΡΡ Π΄ΠΎ ΠΎΠΊΠΈΡΠ»Π΅Π½Π½Ρ ΡΠΏΠ»Π°Π²ΡΠ² Π· Ξ³-TiAl, ΡΡΠ²ΠΎΡΡΡΡΠΈ Π·Π°Ρ
ΠΈΡΠ½Ρ ΠΏΠ»ΡΠ²ΠΊΡ Π· ΠΎΠΊΡΠΈΠ΄Ρ Π°Π»ΡΠΌΡΠ½ΡΡ. ΠΡΠ΄ ΡΠ°Ρ ΠΎΠΊΠΈΡΠ»Π΅Π½Π½Ρ Π΄ΠΈΡΡΠ·ΡΠΉΠ½Π° Π²Π·Π°ΡΠΌΠΎΠ΄ΡΡ TiAlβ Π· ΠΏΡΠ΄ΠΊΠ»Π°Π΄ΠΊΠΎΡ Ξ³-TiAl ΡΠΏΡΠΈΡΠΈΠ½ΡΡ Π·ΠΌΠ΅Π½ΡΠ΅Π½Π½Ρ ΠΊΡΠ»ΡΠΊΠΎΡΡΡ Π°Π»ΡΠΌΡΠ½ΡΡ Ρ ΡΠ°ΡΡ TiAlβ ΡΠ° Π·Π±ΡΠ»ΡΡΠ΅Π½Π½Ρ ΡΠ°ΡΡ TiAlβ. ΠΡΡΠ»Ρ ΠΎΠΊΠΈΡΠ»Π΅Π½Π½Ρ Π² ΠΏΠΎΠΊΡΠΈΠ²Ρ ΡΡΠ²ΠΎΡΡΡΡΡΡΡ ΠΌΡΠΊΡΠΎΡΡΡΡΠΊΡΡΡΠ° Π· ΡΠ°Π·Π°ΠΌΠΈ, ΡΠΎ ΠΌΡΡΡΡΡΡ TiAlβ, TiAlβ ΡΠ° AlβOβ.ΠΡΡΠ»Π΅Π΄ΠΎΠ²Π°Π½ΠΎ ΠΌΠΈΠΊΡΠΎΡΡΡΡΠΊΡΡΡΡ Π°Π»ΡΠΌΠΈΠ½ΠΈΠ΄Π½ΠΎΠ³ΠΎ ΠΏΠΎΠΊΡΡΡΠΈΡ ΠΈ Π΅Π³ΠΎ ΠΏΠΎΠ²Π΅Π΄Π΅Π½ΠΈΠ΅ ΠΏΡΠΈ Π²ΡΡΠΎΠΊΠΎΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ½ΠΎΠΌ ΠΎΠΊΠΈΡΠ»Π΅Π½ΠΈΠΈ. Π‘Π»ΠΎΠΈ Π°Π»ΡΠΌΠΈΠ½ΠΈΠ΄Π° ΡΠΈΡΠ°Π½Π° ΠΈΠ·ΡΡΠ°Π»ΠΈ Ρ ΠΏΠΎΠΌΠΎΡΡΡ ΠΎΠΏΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΈ, ΡΠΊΠ°Π½ΠΈΡΡΡΡΠ΅ΠΉ ΡΠ»Π΅ΠΊΡΡΠΎΠ½Π½ΠΎΠΉ ΠΌΠΈΠΊΡΠΎΡΠΊΠΎΠΏΠΈΠΈ (SΠΠ) Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ Π΄ΠΈΡΠΏΠ΅ΡΡΠ½ΠΎΠ³ΠΎ ΡΠ΅Π½ΡΠ³Π΅Π½ΠΎΡΠΏΠ΅ΠΊΡΡΠΎΠΌΠ΅ΡΡΠ° (EDS) ΠΈ ΡΠ΅Π½ΡΠ³Π΅Π½ΠΎΠ²ΡΠΊΠΈΠΌ Π΄ΠΈΡΡΠ°ΠΊΡΠΈΠΎΠ½Π½ΡΠΌ ΠΌΠ΅ΡΠΎΠ΄ΠΎΠΌ. ΠΡΠΏΡΡΠ°Π½ΠΈΡ ΠΏΡΠΎΠ²ΠΎΠ΄ΠΈΠ»ΠΈ ΠΏΡΠΈ 950Β°C Π² ΡΠ΅ΡΠ΅Π½ΠΈΠ΅ 200 h. Π£ΡΡΠ°Π½ΠΎΠ²Π»Π΅Π½ΠΎ, ΡΡΠΎ Π½Π° ΠΏΠΎΠ΄ΠΊΠ»Π°Π΄ΠΊΠ΅ ΠΈΠ· ΡΠΈΡΠ°Π½ΠΎΠ²ΠΎΠ³ΠΎ ΡΠΏΠ»Π°Π²Π° ΠΎΠ±ΡΠ°Π·ΠΎΠ²Π°Π»ΡΡ TiAlβ. ΠΠΎΠΊΡΡΡΠΈΠ΅ ΠΈΠ· Π°Π»ΡΠΌΠΈΠ½ΠΈΠ΄Π° ΡΠΈΡΠ°Π½Π° ΡΠ»ΡΡΡΠ°Π΅Ρ ΡΡΠΎΠΉΠΊΠΎΡΡΡ ΠΊ ΠΎΠΊΠΈΡΠ»Π΅Π½ΠΈΡ ΡΠΏΠ»Π°Π²ΠΎΠ² ΠΈΠ· Ξ³-TiAl, ΠΎΠ±ΡΠ°Π·ΠΎΠ²ΡΠ²Π°Ρ Π·Π°ΡΠΈΡΠ½ΡΡ ΠΏΠ»Π΅Π½ΠΊΡ ΠΈΠ· ΠΎΠΊΠΈΡΠ»Π° Π°Π»ΡΠΌΠΈΠ½ΠΈΡ. ΠΠΎ Π²ΡΠ΅ΠΌΡ ΠΎΠΊΠΈΡΠ»Π΅Π½ΠΈΡ Π΄ΠΈΡΡΡΠ·ΠΈΠΎΠ½Π½ΠΎΠ΅ Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΠ΅ TiAlβ Ρ ΠΏΠΎΠ΄ΠΊΠ»Π°Π΄ΠΊΠΎΠΉ Ξ³-TiAl Π²Π»Π΅ΡΠ΅Ρ ΡΠΌΠ΅Π½ΡΡΠ΅Π½ΠΈΠ΅ ΠΊΠΎΠ»ΠΈΡΠ΅ΡΡΠ²Π° Π°Π»ΡΠΌΠΈΠ½ΠΈΡ Π² ΡΠ»ΠΎΠ΅ TiAlβ ΠΈ ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΠ΅ ΡΠ»ΠΎΡ TiAlβ. ΠΠΎΡΠ»Π΅ ΠΎΠΊΠΈΡΠ»Π΅Π½ΠΈΡ Π² ΠΏΠΎΠΊΡΡΡΠΈΠΈ ΠΎΠ±ΡΠ°Π·ΡΠ΅ΡΡΡ ΠΌΠΈΠΊΡΠΎΡΡΡΡΠΊΡΡΡΠ° Ρ ΡΠ°Π·Π°ΠΌΠΈ, ΠΊΠΎΡΠΎΡΡΠ΅ ΡΠΎΠ΄Π΅ΡΠΆΠ°Ρ TiAlβ, TiAlβ ΠΈ AlβOβ
The Effect of Experience on Recognition of Motherβs Voice in Preterm Infants
Background: According to existing theories, supportive cares provided through specific kinds of stimuli affect the growth, development
and neurobehavioral functioning of preterm infants. Some of the studies indicate that the fetal heart rate response to
motherβs voice begins in the week 32 of pregnancy. However, the fact that whether preterm infant is able to recognize motherβs live
voice from the voice of a stranger woman is unknown.
Objectives: The present study aimed to compare the effects of motherβs voice and a strangerβs voice on the heart rate of preterm
infants hospitalized in a neonatal intensive care unit (NICU).
Methods: In a clinical trial study, 66 preterm infants hospitalized in the NICU were randomly assigned into three groups of 22
(i.e. motherβs voice and strangerβs voice groups and a silent group). The infantsβ heart rates were recorded by a monitoring system
in all of the three groups each five minutes for 30 minutes overall (10 minutes before, during and after the intervention) in three
consecutive days. Both one-way and repeated measures analysis of variance were used to analyze the data in terms of significant
differences. Also, the chi-square test and analysis of variance were used to compare the demographic variables of the groups.
Results: The heart rate of the infants in the motherβs voice group, strangerβs voice group and the silent group were 133.99 οΏ½ 2.72,
134.26 οΏ½ 2.43 and 137.94 οΏ½ 2.92 per minutes, respectively (P > 0.588) and changed to 143.42 οΏ½ 2.85, 133.22 οΏ½ 2.15 and 138.28 οΏ½ 2.21,
respectively (P = 0.016). Moreover, the infantsβ heart rates were respectively 136.87οΏ½3.38, 132.68οΏ½2.22 and 138.19οΏ½2.65 per minutes,
10 minutes after the intervention (P > 0.345).
Conclusions: No significant difference was found between the mean heart rates of the three groups neither before, nor 10 minutes
after the intervention. However, a significant difference was observed among the three groups during the intervention. Therefore,
we can conclude that the preterm infants can recall and differentiate their mothersβ voice from the voice of a stranger. Then, an
opportunity can be provided during the developmental care for the infants to hear their mothersβ voice
Effects of essential oils of Satureja bachtiarica and Nigella sativa on the efficacy of lactococcosis vaccine in rainbow trout (Oncorhynchus mykiss)
Lactococcosis has been defined as acute septicaemia, which causes economic losses in farmed fish, especially in rainbow trout. This study was done to evaluate the effects of the essential oils of Satureja bachtiarica and Nigella sativa on the efficacy of lactococcosis vaccine in rainbow trout. A total number of 270 fishes with a mean weight of 120 g were obtained; they were randomly divided into nine groups, each with three replicates, after two weeks of adaptation. The groups were: no injection group, vaccine only group, DMSO injection group, vaccine with 50, 100, and 200 micrograms Intraperitoneal injection (IP) injection. Two, four, and six weeks after vaccination, serological and haematological parameters were evaluated. In the sixth week, 1.7Γ10^7 cfu as LD50 96 hrs of Lactococcus garvieae were IP injected and the relative survival percentage was calculated. The results indicated that N. sativa essence is effective on the leukocyte population as the highest number of leukocytes were found in fish receiving high concentration of N. sativa. The relative survival rate of the studied fish decreased with decreasing concentrations of the N. sativa essential oil concentration, with a significant difference with control groups (p<0.05). However, using S. bachtiarica was not significantly effective on the relative survival rate of fish. The results of this study indicated that N. sativa essential oil can be used as adjuvant for L. garvieae vaccine, since it resulted in increasing leukocytes and the relative survival rate although S. bachtiarica was not effective on immune parameters of the studied fish
Thermal Management Systems and Waste Heat Recycling by Thermoelectric Generators-An Overview
With the fast evolution in greenhouse gas (GHG) emissions (e.g., CO2,Β N2O) caused by fossil fuel combustion and global warming, climate change has been identified as a critical threat to the sustainable development of human society, public health, and the environment. To reduce GHG emissions, besides minimizing waste heat production at the source, an integrated approach should be adopted for waste heat management, namely, waste heat collection and recycling. One solution to enable waste heat capture and conversion into useful energy forms (e.g., electricity) is employing solid-state energy converters, such as thermoelectric generators (TEGs). The simplicity of thermoelectric generators enables them to be applied in various industries, specifically those that generate heat as the primary waste product at a temperature of several hundred degrees. Nevertheless, thermoelectric generators can be used over a broad range of temperatures for various applications; for example, at low temperatures for human body heat harvesting, at mid-temperature for automobile exhaust recovery systems, and at high temperatures for cement industries, concentrated solar heat exchangers, or NASA exploration rovers. We present the trends in the development of thermoelectric devices used for thermal management and waste heat recovery. In addition, a brief account is presented on the scientific development of TE materials with the various approaches implemented to improve the conversion efficiency of thermoelectric compounds through manipulation of Figure of Merit, a unitless factor indicative of TE conversion efficiency. Finally, as a case study, work on waste heat recovery from rotary cement kiln reactors is evaluated and discussed.Sadeq Hooshmand Zaferani, Mehdi Jafarian, Daryoosh Vashaee, and Reza Ghomashch
Sensitivity to hydrogen induced cracking, and corrosion performance of an API X65 pipeline steel in H2S containing environment: influence of heat treatment and its subsequent microstructural changes
In this investigation, the effect of microstructural changes and phase equilibria on corrosion behavior and hydrogen induced cracking (HIC) sensitivity of an API X65 pipeline steel was studied. For this purpose, heat treatment was performed at 850 Β°C, 950 Β°C, 1050 Β°C and 1150 Β°C to engineer the desired microstructure of this pipeline steel. Then, the microstructural evolution was performed by optical microscopy, and Field Emission Scanning Electron Microscopy (FE-SEM) equipped with Energy Dispersive X-Ray Spectroscopy (EDS). Corrosion properties were evaluated in H2S environment by open circuit potential (OCP), Potentiodynamic polarization and Electrochemical Impedance Spectroscopy (EIS). As well, HIC sensitivity of the API X65 pipeline steel was assessed by hydrogen charging of the cathode and immediately conducting the tensile test. Microscopy analyses showed that the microstructure of the steel is ferritic-pearlitic together with the islands of martensite/austenite constituents. Increasing the heat treatment temperature reduced the amount of pearlite and increased ferrite grain size. It also stabilized the ferrite content. Corrosion results indicated that no active layer was formed on the surface of this pipeline steel. Also, increasing the heat treatment temperature increased the corrosion resistance and reduced sensitivity to micro-galvanic localized corrosion. As well, results suggested that the sensitivity to HIC in the API X65 pipeline was substantially increased with increasing the amount of pearlite and reducing the amount of ferrite; i.e. at lower heat treatment temperature.publishedVersio
A time-domain control signal detection technique for OFDM
Transmission of system-critical control information plays a key role in efficient management of limited wireless network resources and successful reception of payload data information. This paper uses an orthogonal frequency division multiplexing (OFDM) architecture to investigate the detection performance of a time-domain approach used to detect deterministic control signalling information. It considers a type of control information chosen from a finite set of information, which is known at both transmitting and receiving wireless terminals. Unlike the maximum likelihood (ML) estimation method, which is often used, the time-domain detection technique requires no channel estimation and no pilots as it uses a form of time-domain correlation as the means of detection. Results show that when compared with the ML method, the time-domain approach improves detection performance even in the presence of synchronisation error caused by carrier frequency offset
Derailment-based fault tree analysis on risk management of railway turnout systems
Railway turnouts are fundamental mechanical infrastructures, which allow a rolling stock to divert one direction to another. As those are of a large number of engineering subsystems, e.g. track, signalling, earthworks, these particular sub-systems are expected to induce high potential through various kind of failure mechanisms. This could be a cause of any catastrophic event. A derailment, one of undesirable events in railway operation, often results, albeit rare occurs, in damaging to rolling stock, railway infrastructure and disrupt service, and has the potential to cause casualties and even loss of lives. As a result, it is quite significant that a well-designed risk analysis is performed to create awareness of hazards and to identify what parts of the systems may be at risk. This study will focus on all types of environment based failures as a result of numerous contributing factors noted officially as accident reports. This risk analysis is designed to help industry to minimise the occurrence of accidents at railway turnouts. The methodology of the study relies on accurate assessment of derailment likelihood, and is based on statistical multiple factors-integrated accident rate analysis. The study is prepared in the way of establishing product risks and faults, and showing the impact of potential process by Boolean algebra
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