bluuebunny/crossref_metadata_2025 huggingface dataset:
ANALYZING THE EFFECT OF NOZZLE DIAMETER IN FUSED DEPOSITION MODELING FOR EXTRUDING POLYLACTIC ACID USING OPEN SOURCE 3D PRINTING
Authors: Sukindar Nor Aiman , Ariffin M. K. A. , Baharudin B. T. Hang Tuah , Jaafar Che Nor Aiza , Ismail Mohd Idris Shah
Published: October 2016

Fused deposition modeling (FDM) is one of the Rapid Prototyping (RP) technologies. The 3D Printer has been widely used in the fabrication of 3D products. One of the main issues has been to obtain a high quality for the finished parts. The present study focuses on the effect of nozzle diameter in terms of pressure drop, geometrical error as well as extrusion time. While using polylactic acid (PLA) as a material, the research was conducted using Finite Element Analysis (FEA) by manipulating the nozzle diameter, and the pressure drop along the liquefier was observed. The geometrical error and printing time were also calculated by using different nozzle diameters. Analysis shows that the diameter of the nozzle significantly affects the pressure drop along the liquefier which influences the consistency of the road width thus affecting the quality of the product’s finish. The vital aspect is minimizing the pressure drop to be as low as possible, which will lead to a good quality final product. The results from the analysis demonstrate that a 0.2 mm nozzle diameter contributes the highest pressure drop, which is not within the optimum range. In this study, by considering several factors including pressure drop, geometrical error and printing time, a 0.3 mm nozzle diameter has been suggested as being in the optimum range for extruding PLA material using open-source 3D printing. The implication of this result is valuable for a better understanding of the melt flow behavior of the PLA material and for choosing the optimum nozzle diameter for 3D printing.
THE INFLUENCE OF SURFACE TYPES ON FOOT KINEMATICS DURING RUNNING AND WALKING: A SYSTEMATIC REVIEW
Authors: Abdul Yamin Noor Arifah Azwani , Basaruddin Khairul Salleh , Rusli Wan Mohd Radzi , Razak Norazian , Salleh Ahmad Faizal
Published: October 2016

Variations in running or walking surfaces may contribute to injury, due to the modification of lower extremity motion depending on surface conditions. Limited sources clearly identify that injuries can be caused by altering foot kinematics on numerous surface types. The purpose of this review paper is to identify the relationship between type of surface and foot kinematics whilst running or walking. The search strategy was completed via the Science Direct database and manual searching using a reference list of the reviewed articles. The quality of the reviewed articles was identified via methodological quality assessment. Twelve full-text articles were involved in the quality assessment out of a total of 1455 citations yielded at the beginning of the electronic search. Most of the reviewed papers classified as “high quality” did so by providing sufficient information on research objectives, study design, equipment design, study interest, main outcomes as well as key findings. The majority of the reviewed articles espoused that foot kinematics changing in relation to running or walking surface type and the category of participant. The application of dynamic modelling and finite element analysis was recommended to identify the injury in detail. Thus, further research is suggested to enhance knowledge of injuries caused by running or walking on different surfaces.
CYTOTOXIC ACTIVITY OF LUVUNGA SCANDENS AGAINST HUMAN CANCER CELL LINES
Authors: Al-Zikri Putri Nur Hidayah , Taher Muhammad , Susanti Deny , Arief Ichwan Solachuddin Jauhari
Published: October 2016

Luvunga scandens belongs to the family of Rutaceae which usually inhabit tropical and moist environment. This plant is known as ‘Mengkurat Jakun’ among locals and used traditionally to treat fever and fatigue via decoction. The aim of this study was to investigate the cytotoxic activity of the leaves and stems extracts of L. scandens extract. Extracts of the leaves and stems were obtained from sequential extraction procedures by various organic solvents. All extracts were subjected to cytotoxic study by 3-(4, 5-dimethylthaizol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay. In in vitro cytotoxicity assay, all L. scandens extracts exhibited cytotoxicity against human breast adenocarcinoma (MCF-7) and human lung adenocarcinoma (A549) cell lines. The IC50 values of dichloromethane and methanol extracts from the leaves of L. scandens against MCF-7 cell line were 62.5 µg/mL and 88.0 µg/mL, respectively, whereas IC50 of methanol extract from stem was 81.0 µg/mL. All extracts were less active against A549 cell line where IC50 value were not be determined. The present findings revealed the potential of L. scandens as a cytotoxic agent against MCF-7 cell line. However, further studies should be planned to evaluate role of the plant in cytotoxic activity.
A FACTORIAL ANALYSIS STUDY ON FACTORS CONTRIBUTION TO FERULIC ACID PRODUCTION FROM OIL PALM FROND WASTE
Authors: Ahmad Khushairi Zulsyazwan , Wan Yussof Hafizuddin , Rodzri Nurul Atikah , Abu Samah Rozaimi , Zainol Norazwina
Published: October 2016

Enzymatic hydrolysis of fibre-pressed oil palm frond (FPOPF) was done using mix culture for the production of ferulic acid. Mix culture was prepared by acclimatizing the soil obtained from palm oil plantation with FPOPF substrate for 30 days. The substrate had a ratio of FPOPF to water of 1:10. Design Expert 7.1 was used to aid the experimental design. A half fractional two-level factorial analysis with five factors was selected for the experimental design resulting in a total of 16 runs. The factors controlled were temperature (A; 26°C and 40°C), pH value (B; 5 and 9), agitation speed (C; 0 and 150 rpm), inoculum percentage (D; 2% and 10%), and response time (E; 1 and 3 days). The result obtained showed that the experimental design model was significant with a coefficient of determination value of 0.8978. Two factors that contributed the most to the process were temperature and pH value. This model was proved to be repeatable with a validation test percentage error at 4.15% to 6.83%.
IMPLEMENTING ACTIVE FORCE CONTROL TO REDUCE VIBRATION OF A SHORT LENGTH DRIVE SHAFT
Authors: Mohebbi Mustafa , Hashemi Mahdi , Mailah Musa
Published: October 2016

Vibration is a physical phenomenon involving repeated oscillatory movements or fluctuations at certain frequency and typically undesirable in many applications since it may cause undue failure or damage to the system. In this paper, the vibration of a three degree-of-freedom (DOF) model representing a short length drive shaft has been effectively and robustly suppressed through the implementation of a novel Active Force Control (AFC) used in conjunction with a classic proportional-integral-derivative (PID) controller. The shaft vibration caused by its support and constraint during its operation was simulated using MATLAB and Simulink considering a number of operating and loading conditions. The results proved that when a pure PID controller was implemented, the vibration is indeed reduced but at the expense of longer execution time and producing noticeable frequency oscillation with slight offset. On the other hand, when the AFC loop was engaged by adding it directly in series with the PID controller (PID+AFC) to produce a 2 DOF controller without any need to further tune the PID controller gains, the vibration is significantly reduced with the amplitude hovering a zero datum without any offset and yielding an extremely low frequency trending.
CHARACTERISTICS OF 1500 CC LPG FUELED ENGINE AT VARIOUS OF MIXER VENTURI AREA APPLIED ON TESLA A-100 LPG VAPORIZER
Authors: Setiyo Muji , Waluyo Budi , Husni Mohammad , Karmiadji Djoko Wahyu
Published: October 2016

In the first generation of LPG kit, are called Converter and Mixer (CM), the engine power is influenced strongly by the size of mixer venturi, but this case has not been widely discussed. LPG has lower carbon content than gasoline, so it requires less air to burn. Theoretically, the amount of air to burn LPG is 46% lower than gasoline. However, in practice, the venturi area of the mixer is made from 7.5 mm2 to 10 mm2 per output hp engine. To confirm this, the mixers with venturi area of 705, 960, and 1256 mm2 are applied in Toyota 5A-FE LPG-fueled engine with Tesla A-100 LPG vaporizer. The engine performance characteristics were tested using the Hofmann Dynatest Pro chassis dynamometer and the emissions were tested using QRO-401 engine gas analyzer. The result shows that the venturi area of the mixer has a major influence on the engine power, which generates specific power characteristics. However, differences in the mixer size have little effect on emissions. This study concluded that the Toyota 5A-FE LPG-fueled engine is recommended to use a mixer with venturi area of 960 mm2 (35 mm in diameter).
RE-STORM: REAL-TIME ENERGY EFFICIENT DATA ANALYSIS ADAPTING STORM PLATFORM
Authors: Patan Rizwan , M. Rajasekhara Babu
Published: October 2016

It is necessary to model an energy efficient and stream optimization towards achieve high energy efficiency for Streaming data without degrading response time in big data stream computing. This paper proposes an Energy Efficient Traffic aware resource scheduling and Re-Streaming Stream Structure to replace a default scheduling strategy of storm is entitled as re-storm. The model described in three parts; First, a mathematical relation among energy consumption, low response time and high traffic streams. Second, various approaches provided for reducing an energy without affecting response time and which provides high performance in overall stream computing in big data. Third, re-storm deployed energy efficient traffic aware scheduling on the storm platform. It allocates worker nodes online by using hot-swapping technique with task utilizing by energy consolidation through graph partitioning. Moreover, re-storm is achieved high energy efficiency, low response time in all types of data arriving speeds.it is suitable for allocation of worker nodes in a storm topology. Experiment results have been demonstrated the comparing existing strategies which are dealing with energy issues without affecting or reducing response time for a different data stream speed levels. Finally, it shows that the re-storm platform achieved high energy efficiency and low response time when compared to all existing approaches.
DATA ANALYTICS IN SPATIAL EPIDEMIOLOGY: A SURVEY
Authors: Kather Sharmila Banu , Tripathy BK
Published: October 2016

Spatial data analysis is being used efficiently and the governments have realized that georeferenced data yields more insight with time and locations. Epidemiology is about the study of origin and distribution of diseases and dates back to the 1600s with the instance of cholera in London. Data Science has been evolving and when analyzed with Soft Computing techniques like Rough Set Theory (RST), Fuzzy Sets, Granulation Computing which encompasses the data in its original nature, results can be obtained with accrued accuracy. This survey paper highlights Spatial Data Mining methods used in the field of Epidemiology, identifies crucial challenges and discusses of the use of Soft Computing methods.
REARING SYSTEMS RELATED TO GASTROINTESTINAL PARASITES IN GOATS FROM SELECTED AREA IN TERENGGANU
Authors: Hashim Najat , Mat Yusof Afzan
Published: October 2016

This study was the first attempt to compare the prevalence of gastrointestinal parasites in goats in three different rearing systems. A total of 287 fecal samples were randomly collected from goats in three farms in Terengganu, Malaysia. The samples were processed by using sodium chloride floatation method and observed microscopically. Out of 287 goats, 280 (97.6%) were infected with gastrointestinal parasites. Goats reared under the intensive rearing system reported the highest prevalence of infection (99%), followed by extensive rearing system (98.3%) and the lowest prevalence was reported in the goats reared under the semi-intensive rearing system (96%). The following gastrointestinal parasites were identified in goats in accordance of predominant: Eimeria spp. (89.2%), Strongyloides spp. (45.6%), Strongyle spp. (20.6 %), Moniezia spp. (13.9%) and Trichuris spp. (8.4). Three species showed predominant in goats under the semi- intensive rearing system were Strongyle spp., Strongyloides spp., and Trichuris spp. with the percentage of 33.1%, 83.1% and 10.5%, respectively. Moniezia spp. was the highest in goats under the extensive rearing system which occurred at 26.7%, whereby Eimeria spp. was predominant under intensive rearing system with the infection rate of 99%. The finding suggested that the rearing system might not influence the occurrence of GI parasites in goats. Further study should be conducted to validate this finding.
FLAME PROPAGATION AND BURNING RATES OF METHANE-AIR MIXTURES USING SCHLIEREN PHOTOGRAPHY
Authors: Suhaimi Mohd Suardi , Saat Aminuddin , A. Wahid Mazlan , Mohd Sies Mohsin
Published: October 2016

Different methodology have been shown to produce different results for Markstein length and laminar burning velocity of methane-air mixture.This study attempts to determine the aforesaid parameters using the newly developed closed vessel combustion chamber with Schlieren photography. Markstein length and burning rate of methane-air mixture was determined under the initial pressure of 1 atm, temperature range of 298-302K and equivalence ratio range of 0.7-1.3. Experiments were performed in a centrally ignited 29.16L cylindrical constant volume combustion chamber. Ignition energy was set at 25mJ for each experiment. The images of spherically expanding flame were recorded using Schlieren photography technique at a speed of 2000 frame per second. Analysis of the flame area yield flame radii from which the flame speed and stretch rate could be obtained. These parameters would allow the determination of Markstein length and burning rate of the flame. Results show that Markstein length magnitude increases proportionally with equivalence ratio with a magnitude ranging from 0.125cm to 0.245cm. Maximum burning rate occurs at equivalence ratio of 1.1 with a magnitude of 0.366 m/s. Flame of each equivalence ratio also exhibits fluctuation arising from acoustic disturbance. This disturbance becomes more apparent at higher equivalence ratio.
Amalan Standard Halal Di Negara-Negara Asia Tenggara
Authors: Md. Sawari Siti Salwa , Ghazali Mohd Al'Ikhsan
Published: October 2016

Halal global market shows a significant growth in line with the increasing numbers of world Muslims population. The increasing demand of halal products market is expected to continue to rise in the future. It is therefore, a need to have a standard implementation for halal product all over the world in order to assure the uniformity of halal certification accreditation. By such, this study is to investigate halal standards, and its implementations in Asian countries. In conducting this study, a qualitative approach was applied by utilising library research in collecting the related data. Result of this study indicates that halal standards in Malaysia and other South East Asian countries (Indonesia, Thailand, Brunei and Singapore) are regulated and governed by their own responsible party. Referring to the implementation halal standard, each country has its own characteristics of halal assurance system.Keywords: South East Asian Countries, Standard Halal, Assurance system.
Al-Qadi Abu Ya‘la: Thoughts and Influence on the Development of Legal Theory of Islamic Civilization and Sciences of Jurisprudence
Authors: Yusuf Abdul Azeez
Published: October 2016

Abstract: Al-Qāḍī Abū Ya‘lā ibn al-Farrā’ (380-458 A.H / 990-1065 C.E) is regarded as the most prominent Hanbali scholar and one of the early Muslim jurists who played dynamic roles in formulating a systematic legal framework and constitutional theory on Islamic system of government during the first half of the 5th/11th Century in Baghdad, and which are still found to be relevant in the modern day constitutional legal theories. Attempt would, therefore, be made in this paper to examine the contributions of this Leading Legal Luminary to the Legal theory of Islamic civilization and sciences of jurisprudence of the Ḥanbali Madhhab (Hanbali School of Law). Other areas of relevance critically examined in this paper are his education and legal background, contemporary pursuits of intellectuals and prominent fuqahā’ (jurists) of his time, as well as a detailed account of his notable students, works and influence in the development of the Ḥanbali Madhhab  Key words: Islamic Civilization, Islamic Jurisprudence, Hanbali Madhhab, Hanbali Scholars, Legal theory.
KONSEP ASAS PEMBENTUKAN INDIKATOR BANDAR SEJAHTERA MENURUT PERSPEKTIF ISLAM
Authors: Lagiman Norizam Bin , Ngah Ibrahim , Mustari Ismail , Bashirun Siti Norashikin
Published: October 2016

City is the central development of the human civilization. The emergence of Islam as a greatest religion and most glorious began from the city. The aims of the study are to identify the concepts, principles and characteristics of wellbeing Islamic city and to establish indicators based on Islamic scholars opinion. It is also to measure the level of wellbeing city based on the indicators produced and to identify the implications of planning policy and urban community development. Result shows that, economic, faith and physical scored highest for developing cultural-economic indicators among the population endowment scored min 4.91. Faith-resident reading al-Quran as a daily practice indicator scored 4.90 and physical indicators of the existence of a clean environment scored min 4.89. Overall, the study found that the wellbeing of a city influenced by spiritual compared with physical factors.Keywords: Indicator, City, Development, Well Being, Urban Planning
THE WORD ‘ALLAH’ AND ITS USAGE: AN ANALYSIS INTO THE HISTORY OF THE ARABIC LANGUAGE
Authors: Yaacob Solehah
Published: October 2016

The issue of the word ‘Allah’ is evidence that Malaysia’s society is not yet deeply enlightened on the origins of the Arabic language, that is, the language of the Qur’an. To explain this issue in more details towards the origins of this language of the Qur’an, research on the word ‘Allah’ is sample proof that the nahw systems have been practiced, thus the word ‘Allah’ through an Arabic linguistic nahw approach has to be phrased to determine when did this word appear. Ibnu Manzur, in his book Lisaan al- Arab, had discussed the meaning of the word ‘Allah’ in depth. The word ‘Allah’ in fact originates from the word إِلاَهٌ from the wazn فِعَالٌ that then became wazn مَفْعُوْلٌ or مَأْلُوْهٌ meaning ‘who is worshipped’. Sibawaih had also mentioned, in his book al-Kitab, that pre-Islamic Arabs had used the word لاهٌ, with omission of the second `Lam` in this word ‘Allah’. This means that when the word لاهٌ is perfect or complete in nominative rules it is pronounced as `الله ` where this is only used in the Qur’an. Therefore, Books before the Qur’an had not used the word ‘الله’. Thus research such as this one has to be discussed in details, since this word ‘Allah’ involves the Aqidah of the Muslim Ummah. Keywords: Word “Allah”, Arabic Language, Arabic Literature
TAWARRUQ BERASASKAN KREDIT PRABAYAR TELEFON: TINJAUAN TERHADAP PRODUK PEMBIAYAAN PERIBADI DI RHB ISLAMIC BANK
Authors: Kasmon Siti Aishah , Noordin Kamaruzaman
Published: October 2016

Tawarruq was introduced in Malaysia as an alternative to controversial bayʻ al-ʻῑnah. However, the second type of tawarruq which is organized tawarruq was disputed by among scholars. The opponents claimed that the implementation of organized tawarruq is not complying Shariah requirements. The introduction of airtime credit as an underlying asset in tawarruq transaction by Sedania As Salam Capital Sdn Bhd (Sedania) is seems to neutralize the argumentation. Hence, this study aimed to review the implementation of tawarruq in personal financing product using airtime credit at Sedania’s first client which is RHB Islamic Bank (RHBIB). Interview sessions with the representatives of Sedania and RHBIB will be held in collecting the information of the modus operandi and also using the literature review in studying the tawarruq concept. The study found that choosing Sedania as a platform in doing tawarruq transaction by using airtime credit as the commodity is the best solution in personal financing product. However, the consumption of this underlying asset in bigger market such as corporate banking and treasury should be considered and more research about this are suggested.     Keywords: Tawarruq, Airtime Credit, RHB Islamic Bank, Sedania as Salam Capital Sdn Bhd, Personal Financing, Underlying Asset
INTENTION TO CONTRIBUTE IN CORPORATE WAQF: APPLYING THE THEORY OF PLANNED BEHAVIOUR
Authors: Hasbullah Nurul Adilah , Khairi Khairil Faizal , Ab. Aziz Muhammad Ridhwan
Published: October 2016

Corporate waqf has contributed a great change into the waqf system as a whole and been generally accepted as a way of waqf practice. However, the literature that discusses about the factors influencing people to contribute or involve in this practice is very limited. Prior to action, intention is taken place. Therefore, this study aims to examine the factors influencing people’s intention to contribute in corporate waqf, particularly to the employees of Majlis Agama Islam Wilayah Persekutuan (MAIWP), based on the theory of planned behaviour (TPB). A set of a questionnaire was constructed in order to measure the validity of the theory towards people’s intention in contributing for corporate waqf. The result of this study found that attitude, subjective norm and perceived behavioural control were significantly related to intention to contribute in corporate waqf among people.Keywords: Corporate Waqf, Intention to Contribute in Corporate Waqf, Theory of Planned Behaviour
APLIKASI TAKAFUL MODEL WAKAF DI MALAYSIA: KEPERLUAN DAN PERMASALAHANNYA
Authors: Rosele Muhammad Ikhlas , Johari Abdul Hakim
Published: October 2016

Takaful coverage schemes are increasingly accepted by society today, especially in Malaysia. However, it does not mean that the system has been set up by takaful companies really meet the Shariah principles or does not arise any issues. Among the issues that arise are the tabarru' contract in takaful practices have a downside though is not seen. A variety of solutions put forward to overcome that issue, among them introducing the waqf based takaful model. Therefore, this research will do a review and preliminary analysis of the needs of the waqf based takaful model in Malaysia. In addition, this study will identify the problems that exist if the waqf based takaful model applied in Malaysia. Kata Kunci: Takaful, model wakaf, tabarru’, keperluan.
Potensi Keterdedahan Risiko Syariah Syarikat Pengendali Takaful Terpilih Di Malaysia
Authors: Mohamed Yusof Mohd Faiz , Borhan Joni Tamkin , Romli Nurhanani
Published: October 2016

Nowadays, various Islamic financial products have been developed and have grown tremendously in the financial markets, including Islamic equity, Islamic banking and takaful. The Islamic finance industry has its own uniqueness compared to the conventional financial industry due to the Islamic finance industry has a need for Shariah compliance in Islamic finance industry as known as Shariah risk. Globally, Islamic capital market was faced incident of Shariah risk in the end 2007 when Sheikh Taqi Uthmani has declared that 85% of sukuk issuance in the market are non Shariah compliant in the end of 2007 and cause a decrease of sukuk issuance in the following years in 2008. There are also dispute cases in Islamic banking in Malaysia such as issue of contract Bay 'Bithaman Ajil (BBA) is not shariah compliant. The takaful industry in Malaysia is also exposed to Shariah risks due to the shariah compliance requirements in all operations and activities of the takaful operator. Therefore, this study will describe the key elements that results shariah risk in Islamic finance. The research will identified potential of shariah risk using a qualitative methodology based on research data from five informants who were experienced shariah compliance management in takaful operator. This study will analyze qualitative data using a computerized program Altas.ti 7. The study infers that there are potential of Shariah risk and incident of Shariah risk in activities and operation of selected takaful operator in Malaysia.
Copula approach to select input/output variables for DEA
Authors: Alpay Olcay , Aktürk Hayat Elvan
Published: October 2016

Determination of the input/output variables is an important issue in Data Envelopment Analysis (DEA). Researchers often refer to expert opinions in defining these variables. The purpose of this paper is to propose a new approach to determine the input/output variables, it is important to keep in mind that especially when there is no any priori information about variable selection. This new proposed technique is based on a theoretical method which is called “Copula”. Copula functions are used for modeling the dependency structure of the variables with each other. Also we use the local dependence function which analyzes the point dependency of variables of copulas to define the input/output variables. To illustrate the usefulness of the proposed approach, we conduct two applications using simulated and real data and compare the efficiencies in DEA. Our results show that new approach gives values close to perfection.
Distinct subcellular mechanisms for the enhancement of the surface membrane expression of SK2 channel by its interacting proteins, α‐actinin2 and filamin A
Authors: Zhang Zheng , Ledford Hannah A. , Park Seojin , Wang Wenying , Rafizadeh Sassan , Kim Hyo Jeong , Xu Wilson , Lu Ling , Lau Victor C. , Knowlton Anne A. , Zhang Xiao‐Dong , Yamoah Ebenezer N. , Chiamvimonvat Nipavan
Published: October 2016

Key points

Ion channels are transmembrane proteins that are synthesized within the cells but need to be trafficked to the cell membrane for the channels to function.

Small‐conductance, Ca2+‐activated K+ channels (SK, KCa2) are unique subclasses of K+ channels that are regulated by Ca2+ inside the cells; they are expressed in human atrial myocytes and responsible for shaping atrial action potentials.

We have previously shown that interacting proteins of SK2 channels are important for channel trafficking to the membrane.

Using total internal reflection fluorescence (TIRF) and confocal microscopy, we studied the mechanisms by which the surface membrane localization of SK2 (KCa2.2) channels is regulated by their interacting proteins.

Understanding the mechanisms of SK channel trafficking may provide new insights into the regulation controlling the repolarization of atrial myocytes.

The normal function of ion channels depends critically on the precise subcellular localization and the number of channel proteins on the cell surface membrane. Small‐conductance, Ca2+‐activated K+ channels (SK, KCa2) are expressed in human atrial myocytes and are responsible for shaping atrial action potentials. Understanding the mechanisms of SK channel trafficking may provide new insights into the regulation controlling the repolarization of atrial myocytes. We have previously demonstrated that the C‐ and N‐termini of SK2 channels interact with the actin‐binding proteins α‐actinin2 and filamin A, respectively. However, the roles of the interacting proteins on SK2 channel trafficking remain incompletely understood. Using total internal reflection fluorescence (TIRF) microscopy, we studied the mechanisms of surface membrane localization of SK2 (KCa2.2) channels. When SK2 channels were co‐expressed with filamin A or α‐actinin2, the membrane fluorescence intensity of SK2 channels increased significantly. We next tested the effects of primaquine and dynasore on SK2 channels expression. Treatment with primaquine significantly reduced the membrane expression of SK2 channels. In contrast, treatment with dynasore failed to alter the surface membrane expression of SK2 channels. Further investigations using constitutively active or dominant‐negative forms of Rab GTPases provided additional insights into the distinct roles of the two cytoskeletal proteins on the recycling processes of SK2 channels from endosomes. α‐Actinin2 facilitated recycling of SK2 channels from both early and recycling endosomes while filamin A probably aids the recycling of SK2 channels from recycling endosomes.
Oscillatory dynamics and functional connectivity during gating of primary somatosensory responses
Authors: Wiesman Alex I. , Heinrichs‐Graham Elizabeth , Coolidge Nathan M. , Gehringer James E. , Kurz Max J. , Wilson Tony W.
Published: October 2016

Key Points

Sensory gating is important for preventing excessive environmental stimulation from overloading neural resources.

Gating in the human somatosensory cortices is a critically understudied topic, particularly in the lower extremities.

We utilize the unique capabilities of magnetoencephalographic neuroimaging to quantify the normative neural population responses and dynamic functional connectivity of somatosensory gating in the lower extremities of healthy human participants.

We show that somatosensory processing is subserved by a robust gating effect in the oscillatory domain, as well as a dynamic effect on interhemispheric functional connectivity between primary sensory cortices.

These results provide novel insight into the dynamic neural mechanisms that underlie the processing of somatosensory information in the human brain, and will be vital in better understanding the neural responses that are aberrant in gait‐related neurological disorders (e.g. cerebral palsy).

Sensory gating (SG) is a phenomenon in which neuronal responses to subsequent similar stimuli are weaker, and is considered to be an important mechanism for preventing excessive environmental stimulation from overloading shared neural resources. Although gating has been demonstrated in multiple sensory systems, the neural dynamics and developmental trajectory underlying SG remain poorly understood. In the present study, we adopt a data‐driven approach to map the spectrotemporal amplitude and functional connectivity (FC) dynamics that support gating in the somatosensory system (somato‐SG) in healthy children and adolescents using magnetoencephalography (MEG). These data underwent time‐frequency decomposition and the significant signal changes were imaged using a beamformer. Voxel time series were then extracted from the peak voxels and these signals were examined in the time and time‐frequency domains, and then subjected to dynamic FC analysis. The results obtained indicate a significant decrease in the amplitude of the neural response following the second stimulation relative to the first in the primary somatosensory cortex (SI). A significant decrease in response latency was also found between stimulations, and each stimulation induced a sharp decrease in FC between somatosensory cortical areas. Furthermore, there were no significant correlations between somato‐SG metrics and age. We conclude that somato‐SG can be observed in SI in both the time and oscillatory domains, with rich dynamics and alterations in inter‐hemispheric FC, and that this phenomenon has already matured by early childhood. A better understanding of these dynamics may provide insight to the numerous psychiatric and neurologic conditions that have been associated with aberrant SG across multiple modalities.
Altering intracellular pH reveals the kinetic basis of intraburst gating in the CFTR Cl− channel
Authors: Chen Jeng‐Haur , Xu Weiyi , Sheppard David N.
Published: October 2016

Key points

The cystic fibrosis transmembrane conductance regulator (CFTR), which is defective in the genetic disease cystic fibrosis (CF), forms a gated pathway for chloride movement regulated by intracellular ATP.

To understand better CFTR function, we investigated the regulation of channel openings by intracellular pH.

We found that short‐lived channel closures during channel openings represent subtle changes in the structure of CFTR that are regulated by intracellular pH, in part, at ATP‐binding site 1 formed by the nucleotide‐binding domains.

Our results provide a framework for future studies to understand better the regulation of channel openings, the dysfunction of CFTR in CF and the action of drugs that repair CFTR gating defects.

Cystic fibrosis transmembrane conductance regulator (CFTR) is an ATP‐gated Cl− channel defective in the genetic disease cystic fibrosis (CF). The gating behaviour of CFTR is characterized by bursts of channel openings interrupted by brief, flickery closures, separated by long closures between bursts. Entry to and exit from an open burst is controlled by the interaction of ATP with two ATP‐binding sites, sites 1 and 2, in CFTR. To understand better the kinetic basis of CFTR intraburst gating, we investigated the single‐channel activity of human CFTR at different intracellular pH (pHi) values. When compared with the control (pHi 7.3), acidifying pHi to 6.3 or alkalinizing pHi to 8.3 and 8.8 caused small reductions in the open‐time constant (τo) of wild‐type CFTR. By contrast, the fast closed‐time constant (τcf), which describes the short‐lived closures that interrupt open bursts, was greatly increased at pHi 5.8 and 6.3. To analyse intraburst kinetics, we used linear three‐state gating schemes. All data were satisfactorily modelled by the C1 ↔ O ↔ C2 kinetic scheme. Changing the intracellular ATP concentration was without effect on τo, τcf and their responses to pHi changes. However, mutations that disrupt the interaction of ATP with ATP‐binding site 1, including K464A, D572N and the CF‐associated mutation G1349D all abolished the prolongation of τcf at pHi 6.3. Taken together, our data suggest that the regulation of CFTR intraburst gating is distinct from the ATP‐dependent mechanism that controls channel opening and closing. However, our data also suggest that ATP‐binding site 1 modulates intraburst gating.
Molecular recognition at cholinergic synapses: acetylcholine versus choline
Authors: Bruhova Iva , Auerbach Anthony
Published: October 2016

Key points

Neuromuscular acetylcholine (ACh) receptors have a high affinity for the neurotransmitter ACh and a low affinity for its metabolic product choline.

At each transmitter binding site three aromatic groups determine affinity, and together provide ∼50% more binding energy for ACh than for choline.

Deprotonation of αY190 by a nearby lysine strengthens the interaction between this aromatic ring and both ACh and choline.

H‐bonds position ACh and choline differently in the aromatic cage to generate the different affinities.

Acetylcholine (ACh) released at the vertebrate nerve‐muscle synapse is hydrolysed rapidly to choline (Cho), so endplate receptors (AChRs) are exposed to high concentrations of both of these structurally related ligands. To understand how these receptors distinguish ACh and Cho, we used single‐channel electrophysiology to measure resting affinities (binding free energies) of these and other agonists in adult‐type mouse AChRs having a mutation(s) at the transmitter‐binding sites. The aromatic rings of αY190, αW149 and αY198 each provide ∼50% less binding energy for Cho compared to ACh. At αY198 a phenylalanine substitution had no effect, but at αY190 this substitution caused a large, agonist‐independent loss in binding energy that depended on the presence of αK145. The results suggest that (1) αY190 is deprotonated by αK145 to strengthen the interaction between this benzene ring and the agonist's quaternary ammonium (QA) and (2) AChRs respond strongly to ACh because an H‐bond positions the QA to interact optimally with the rings, and weakly to Cho because a different H‐bond tethers the ligand to misalign the QA and form weaker interactions with the aromatic groups. The results suggest that the difference in ACh versus Cho binding energies is determined by different ligand positions within a fixed protein structure.
Suggested Guide for Geotechnical Sampling and Testing of Backfill and Borrow for Safety Related Nuclear Structures
Authors: Massoudi Nasser
Published: October 2016

For licensing, design, and construction of nuclear facilities, the investigation of engineering properties of soil borrow and backfill materials is a regulatory requirement, for they impact the performance of these facilities. For instance, the U.S. Nuclear Regulatory Commission (NRC) specifically requires that all applications for nuclear power plants address the source, quantity, static, and dynamic engineering properties of borrow and backfill materials. However, in the nuclear industry, a clear road map does not exist for meeting these requirements. As such, planning, investigation, and/or processes that are needed to address these regulatory requirements become a challenge to applicants. The absence of such a road map can also result in incomplete or unnecessary investigations, licensing cycles, and/or delays. This paper outlines a recommended practice, including steps to design a geotechnical sampling and laboratory investigation program toward addressing these regulatory requirements, with nuclear quality assurance and licensing requirements in perspective. While the steps in this paper may serve as useful guides, requirements vary from project to project; therefore, all efforts should be on developing an investigation program that is project specific in order to meet the actual project objectives. Additionally, this paper provides guidance on presenting the investigation results in regulatory documents.
Parameter Analysis of the Static Droplets Phase Transformation Under the Pressure Variation Condition
Authors: Zhao Fulong , Liu Qianfeng , Bo Hanliang
Published: October 2016

The steam-water separator is a vital important plant in the steam generator, whose function is to remove transported small droplets in the vapor stream and provide the high quality saturated steam for the steam turbine. The performance of the steam-water separator in the steam generator has a great impact on the safety and economy of the nuclear power station. The steam-water separation mechanism is far from maturity as a result of the complexity of the separator structure and the interaction of the steam, droplets together with the liquid film. Our research team tries to build a new research route about the steam-water separation mechanism from the microcosmic behavior aspects of the droplets including the production, movement, collision, extinction as well as the phase transformation. When the droplets move during the steam-water separator, the pressure could decrease continuously due to the resistance and the structure variation, which may break the liquid-vapor equilibrium and make the droplets evaporate and then could greatly influence the steam-water separating characteristics. This paper builds a hydrodynamic-kinetic model on the static droplets phase transformation under the pressure variation condition based on the physics phenomenon description of the droplets evaporation as well as the mechanism explanation. Through different kinds of calculations by change of the time step, the model has been proved to be independent on the time step. In order to make sure that the new model is correct, this paper compares the calculation results with the experimental ones and finds that the calculation results are in wonderful accordance with the existing experimental data. The relative errors between the calculation results and the experimental ones are between ± 5%. At last, this paper conducts the detailed sensitivity analysis of different relative parameters, which are useful for the understanding of the process of the droplets evaporation as well as could deepen the comprehension of the droplets phase transformation mechanism under the condition of the pressure change. The calculation results show that the evaporation characteristics of the static droplets under the pressure variation condition are predominantly influenced by the initial pressure, the ultimate pressure of the environment, as well as the difference of the initial and ultimate pressure. In addition, the initial radius of the droplets and the environment temperature can have a great impact on the droplets evaporation characteristics This model could provide the theoretical reference for further study of the process of the droplets phase transformation during transport in the steam-water separator as well as the steam-water separating performance of the separator, which can guide the design of the steam-water separation plants.
Electron Beam Weldability of AA6061-T6 Aluminum Straps for U-Mo Follower Fuel Assembly Manufacturing
Authors: Kim Soo-sung , Jeong Yong-jin , Park Jong-man , Lee Yoon-sang , Lee Chong-tak
Published: October 2016

A procedure for Electron Beam Welding (EBW) was developed for the manufacturing of a follower fuel assembly made of an AA 6061-T6 aluminum straps for a U-Mo plate-type fuel proposed to be used in the future in Korea’s Kijang Research Reactor (KJRR) project. The initial welding trials of the weld samples were carried out with a high vacuum chamber using the EBW process. After investigating the welds, EB welding parameters for the full-sized samples were optimized for the required depth of penetration and weld quality. Subsequently, the weld samples made by the filler specimens showed higher shearing strengths than those of the non-filler specimens. This procedure made by EBW process was also confirmed based on the results of the shearing strength test, an examination of the macro-cross sections, and the fracture surfaces of the welded specimens.
FLEX Loss of Instrumentation Guidance for PWRs Enhances Severe Accident Diagnostics
Authors: Lutz Robert J. , Lynde James , Pierson Steven
Published: October 2016

The industry response to the Nuclear Regulatory Commission (NRC) Order EA-12-049 is based on a set of Diverse and Flexible Coping Strategies (commonly referred to as FLEX) for beyond design basis external events as described in NEI 12-06. The Pressurized Water Reactors Owners Group (PWROG) developed generic guidance for response to these Beyond Design Basis External Events (BDBEE), called FLEX Support Guidelines (FSGs). These guidelines are referenced from the plant Emergency Operating Procedures (EOPs) when it is determined that an event exhibits certain beyond design basis characteristics such as an Extended Loss of all AC Power (ELAP). These generic FLEX Support Guidelines provide a uniform basis for all PWRs to implement the FLEX guidance in NEI 12-06 that was endorsed by the NRC to maintain core, containment and spent fuel cooling.

The PWROG generic FSGs include guidance in FSG-7, “Loss of Vital Instrumentation or Control Power” for obtaining information for key plant parameters in an ELAP event. The key parameters were selected based on industry guidance and plant specific implementation. This set of key parameters will allow the licensed operators to have vital instrumentation to safely shutdown the core and maintain the core in a shutdown condition, including core, containment and spent fuel pool cooling. These parameters are used in the EOPs as well as the FSGs that are designed to mitigate a beyond design basis event. The requirements of NEI 12-06, as implemented through the FSGs, enhance both availability and reliability of instrumentation by requiring diverse methods of providing DC power for instrumentation and control as well as protection of instrumentation from the beyond design basis event.

The subsequent implementation of this guidance at the Byron Station has proven to also be beneficial for diagnosis of severe accident conditions (where core cooling could not be maintained). The same parameter values that are needed to verify core, containment and spent fuel cooling prior to core damage are also needed to diagnose severe accident conditions. Guidance provided within FSG-7, as implemented at the Byron Station, contains several layers of diverse methods to obtain parametric values for key variables that can be especially useful when the environmental qualification is exceeded for the primary instrumentation that provides this information. The methods range from the use of self-powered portable monitoring equipment to the use of local mechanical instrumentation. The FSG-7 guidance is referenced from the Byron Severe Accident Management Guidance (SAMG) to either obtain parameter information during a severe accident or to validate the information that is available from the primary instrumentation.
Orientation Relationships of Delta Hydrides in Zirconium and Zircaloy-4
Authors: Pshenichnikov Anton , Stuckert Juri
Published: October 2016

The fundamental investigation reported here was motivated by the controversial and incomplete data for zirconium δ-hydride orientation relationships. For the studies, electron back scattered diffraction analysis (EBSD) was used. Formation of zirconium δ-hydrides and their bulk distribution in zirconium and Zircaloy-4 were investigated. On the basis of the grain boundary spectra and the analysis of microtexture, the orientation relationships between δ-hydrides and the α-Zr matrix were refined. It was found that almost all authors, who criticised each other for years, have established the correct relationships. Seven variants of δ-hydride accommodation in the zirconium matrix were summarised in the table of possible orientation relationships.
The Importance of Reliable Indications for Accident Management
Authors: Lutz Robert J. , Williamson Bill T.
Published: October 2016

The accidents at the Three Mile Island Unit 2 (TMI-2) and Fukushima Daiichi Units 1, 2, and 3 demonstrate the critical importance of accurate, relevant, and timely information on the status of reactor systems during a severe accident. There is evidence that the failure of key instrumentation to provide reliable information to the control room licensed operators contributed to the severity of the accident at both TMI and Fuskushima Daiichi. These events also highlight the critical importance of understanding and focusing on the key elements of system status information in an environment where operators may be overwhelmed with superfluous and sometimes conflicting data and yet have to make urgent decisions. While progress in these areas has been made since TMI-2, the accident at Fukushima suggests there may still be some potential for further improvement in critical plant instrumentation. As a result, several approaches are being employed to provide better information to emergency response personnel during a severe accident.

The first approach being taken by the PWROG and BWROG is the identification of methods to obtain information related to key plant parameters when there is a loss of dc power for instrumentation and control. The FLEX guidance in NEI 12-06 requires that reliable instrumentation be available to ensure core, containment and spent fuel pool cooling is maintained for the beyond design basis events for which FLEX was intended. For the most part, this instrumentation that is important for FLEX is the same instrumentation that is used for diagnosis of severe accident conditions and challenges to fission product barriers. Generic FLEX Support Guidelines have been developed to provide a uniform basis for plants to meet the NEI 12-06 requirements that includes methods to obtain key parameter values in the event of a loss of all dc instrument power.

The PWROG and the BWROG have also taken a complimentary approach to provide Technical Support Guidance (TSG) for instrumentation during a severe accident. This approach identifies the primary instrumentation as well as alternate instrumentation and other tools to validate the indications from the primary instrumentation. The validation consists of: a) comparing the primary instrument indications to the alternate instrumentation, b) comparing instrument indications to related instrumentation, c) comparing instrument indications and trends to expected trends based on the accident progression and actions already implemented, and d) comparing instrument indications to information in calculational aids.