bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and Field Application of an Iron Tolerant Scale Inhibitor for use in Fracturing Completions and Production
Authors: Davies H. , Toole M. , Higgins R.
Published: June 2018

Produced waters are increasingly found to contain high levels of dissolved iron, with typical ferrous iron concentrations ranging from a few ppm to several hundred ppm. The presence of iron can cause issues in production, one problem being a detrimental effect on the performance of scale inhibitors. The aim of this work was to investigate scale inhibitor chemistries with improved iron tolerance, and apply a new product in the field to address a severe inorganic scale issue that had been encountered.

Using static bottle tests to assess brine compatibility and anaerobic dynamic scale loop tests to assess scale inhibition efficiency, a wide variety of scale inhibitor chemistries containing different functional groups were screened. The aim was to identify an inhibitor which would give the best performance against calcium carbonate scale in the presence of up to 100ppm Fe2+. Previous studies have shown that the inhibition of calcium carbonate scale is more adversely affected by the presence of iron than the inhibition of barium sulfate scale, and as calcium carbonate was the main challenge in the field case the emphasis was placed on inhibiting this scale type.

Initial compatibility studies revealed the additives with the best brine compatibility, and around nine additives were taken forward for performance testing. It was found that acrylic acid based copolymers demonstrated reasonable scale control at 5-20 ppm Fe2+, but at higher iron the high dose levels required meant that the limit of compatibility was reached before complete scale control had been achieved. The best performing additive for calcium carbonate was found to be a phosphonate derivative. A field trial was conducted in a predominantly calcium carbonate scaling environment as a proof of concept and scale inhibitor residuals were monitored over a 5-month period. After this successful study, further lab experiments were performed with the chosen inhibitor to demonstrate good calcium carbonate control in the presence of up to 100 ppm Fe2+.

A comprehensive investigation of different scale inhibitor types resulted in an optimum chemistry to control calcium carbonate scale in the presence of high concentrations of ferrous iron. Applying this chemistry in the field has demonstrated better scale control than was being achieved with the previous scale inhibitor.
Development of the First Readily Biodegradable OECD306 Phosphonated Amino Acid Chemistry for the Control of Calcium Carbonate and Calcium Sulphate in HTHP and UHT Unconventional Productions
Authors: Di Toto Raul Antonio , Bruyneel Frederic , Parravicini Davide , Kan Amy T. , Tomson Mason B. , Yan Fei
Published: June 2018

The paper describes the development of the first readily biodegradable - in seawater - phosphonated amino acid chemistry (PHAAC), which is able to control calcite and calcium sulphate scale under unconventional HTHP1 conditions (simulated Shearwater field conditions and T/P up to 250°C/1,000bar). This novel chemistry is aimed to support unconventional and ultra HTHP productions in a cost-wise sustainable manner.

The chemistry development is described from the selection of the suitable chemical functionalities through the evaluation of the "must have" properties – brine compatibility, thermal resistance, eco-toxicity profile – to the assessment of performance for calcite, calcium and barium sulphate by dynamic and static scale inhibition tests under uniquely severe conditions (T= 55°C-250°C, salinity = max. 250,000ppm, Calcium = max. 18,960ppm). Successful squeeze simulation was tested at high temperature with a high Ca connate water. Software simulations - Pitzer electrolyte theory - were used to preliminary screen out and define conditions.

The novel chemistry, when compared to industry benchmark inhibitors from low (55°C) to ultra high temperature (250°C), showed an extremely positive overall performance gap. The product thermal resistance evaluation and its impact on chemical stability, properties and performance, is presented showing that stability of the chemical structure - only 1.3% degradation after 7 days at 160°C - eliminates the performance drop when conditions get severe. Minimum inhibitor concentration of the novelty chemistry is up to 10 folds less than conventional chemistries in dynamic scale rig tests and squeeze life is excellent, allowing remarkable cost saving in treating scale in extreme conditions. Detrimental effect of Fe++ on performance and chemical compatibilities are also assessed. Negligible toxicity against marine species and readily biodegradability in seawater makes the chemistry suitable for offshore operations in OSPAR countries. Presented results coupled to ease of detection proof that the new experimental environmentally friendly scale inhibitor can be successfully deployed in HTHP applications for the control of calcium carbonate and calcium sulphate under extremely severe regimes.

The novel chemistry is the first readily biodegradable (OECD306) phosphonate for scale inhibitor applications in HTHP unconventional conditions. It sets new levels of performance in the control of frequently encountered scale types in O&G. The documented inhibitor properties and performance, confirm that it can be a game changer for flow assurance strategies in unconventional productions.
Scale Management in Monoethylene Glycol MEG Systems - A Review
Authors: Seiersten Marion , Kundu Shiv Shankar
Published: June 2018

The paper reviews operational issues that arise when MEG is used for hydrate inhibition, especially when it is regenerated and recirculated. Thermodynamic equilibrium software can assess the scaling risk to some extent. Utilisation of data on nucleation and growth of scale formers like calcium carbonate can enhance the accuracy of the predictions.

The presence of MEG and the conditions encountered in MEG systems favour aragonite crystallisation when the MEG solutions become supersaturated in CaCO3. MEG retards the growth rate of all three CaCO3 polymorphs, but the reduction is smaller for aragonite than for calcite and vaterite. The growth rate of siderite is also slowed down by MEG. However, MEG does not inhibit the nucleation and growth of carbonates.

Alkalinity in recycled MEG will enhance the scaling risk downstream of the MEG injection point when there is calcium in the produced water. Scale can be mitigated by scale inhibitors, but the selection process must ensure that the chemicals are tested at relevant conditions; i.e. with the expected MEG concentration, alkalinity and pH.

Many MEG recovery units have a pre-treatment system for controlled removal of carbonates and to some extent hydroxides. This reduces the amount of scale that may form in the regeneration system. In the pre-treatment, alkalinity dosed as hydroxide and/or carbonate forces precipitation of calcium, strontium and iron carbonates and magnesium hydroxide. The supersaturation is generally so high that scale inhibitors are not able to prevent precipitation of the solids.
Simulating Squeeze Treatments in Wells Completed with Inflow Control Devices
Authors: Kaur Amarpreet , Stalker Robert , Graham Gordon M.
Published: June 2018

The advent of wells with extremely long producing intervals, extended-reach and multilateral wells, typically completed in heterogeneous formations, brings with it challenges regarding completion design to maximize overall production in a sustained manner. Judicious placement of Inflow Control Devices (ICDs) can ensure a more even inflow of fluids along the full length of the interval, delaying water or gas breakthrough and in some cases restricting water production. Such devices also influence the placement of chemical treatments, such as scale-inhibitor "squeeze" treatments, which in turn affects the subsequent treatment lifetimes and efficiency.

This paper presents a new analytical model to explicitly simulate the effect of ICDs on squeeze treatments and, in particular, on treatment placement and consequent lifetimes. The explicit method of modelling ICDs, which is based on Bernoulli's theorem of constricted flow through a pipe, is compared with other implicit phenomenological approaches, such as modelling the effect of an ICD as a damaged region using a dual-permeability model. By this comparison, the relevance of dual permeability modelling for simulating ICDs is presented. The relationship between chemical placement and inhibitor return has been clearly demonstrated in other publications (James et al., 2005, Sorbie et al. 2005). This paper illustrates the additional effects that ICDs bring to the placement challenge, highlighting the key parameters that can influence the zonal injectivity behaviour. The presence of ICDs in the well is shown not only to benefit the well's inflow profile during production but can also favourably influence the outcome of squeeze chemical treatments.

In summary, the paper describes the development of an important new tool to assist in the design of optimum chemical treatment strategies in wells completed with ICDs, without the need to use more complex reservoir simulators for near-wellbore treatment in complex completions.
Iron Sulphide Inhibition and Interaction with Zinc and Lead Sulphide
Authors: Al-Harbi B. G. , Graham A. J. , Sorbie K. S.
Published: June 2018

Iron sulphide (FeS), zinc sulphide (ZnS) and lead sulphide (PbS) are considered to be among the most challenging scales in terms of inhibition and removal. They can form by direct reaction of aqueous sulphide species with dissolved Fe, Zn and/or Pb and by the exchange between aqueous sulphide species with preformed iron compounds, such as iron oxide hydroxide. These existing iron compounds may have formed during production and/or intervention, such as an acid treatment. Similarly, PbS and ZnS can form by extracting sulphide from a more soluble sulphide scale i.e. Zn exchanging with Fe in FeS. The objective of this work was to investigate FeS formation and inhibition under a range of conditions including pH, temperature, salinity and proposed mode of formation. In addition, the interaction between iron, zinc and lead within solutions containing sulphide species was investigated

The majority of this study was conducted under anaerobic conditions, with the scale formation and/or inhibition experiments being monitored by inductively coupled plasma (ICP) analysis, pH and particle size measurements. Among the tested scale inhibitors, two showed high efficiency against iron sulphide, however high pH and salinity had a detrimental impact on the performance of one of these products. Interestingly, these scale inhibitors prevented iron sulphide deposition even under aerobic conditions i.e. iron hydroxide partially preformed. Moreover, at sufficiently high concentrations of scale inhibitor, the deposition of zinc sulphide and lead sulphide was prevented even when these scales were formed via cation displacement i.e. zinc and lead displaced sulphide ions from pre-formed iron sulphide. The route of formation for FeS, ZnS and PbS was seen to have a significant impact on the inhibition process.

The particle sizes of inhibited (suspended) FeS were significantly lower than the blank FeS samples, with this effect increasing with increased scale inhibitor concentration. This difference in particle size may have an important influence on in-line filter blocking tests and produced water quality issues.
Application of Electroless Nickel Coating as a Scaling Resistant Alloy in Thermal Production
Authors: Zhu Da , Gong Lu , Qiu Xiaoyong , Hu Wenjihao , Huang Jun , Zhang Ling , Fattahpour Vahidoddin , Mahmoudi Mahdi , Luo Jing-Li , Zeng Hongbo
Published: June 2018

The scaling has been found to be a major problem in thermal production, such as in the Steam-Assisted Gravity Drainage (SAGD) operation. In addition to providing a favorite environment for corrosion, scaling could result in extreme plugging in sand control devices. Therefore, any coatings for the equipment and completion in thermal production should provide significant anti-scaling surface properties.

This paper presents a detailed study, including field and laboratory testing, on application of the Electroless Nickel Coating (EN-coating) in thermal production environment. Initially, EN-coated and uncoated carbon steel samples were tested in laboratory to assess the scale, hardness and adhesion of inorganic and organic materials.

Successful laboratory testing lead to a field testing plan, which involves deploying the EN-coated and uncoated samples into a horizontal well for thermal production. The specimens were recovered after certain time and a comprehensive X-ray Photoelectron Spectroscopy (XPS) and Energy-Dispersive Spectroscopy (EDS) were performed to assess accumulation of fouling substances on EN-coated and uncoated carbon steel.

This study suggests the application of the EN-coating technology to solve the problems caused by scale, and adhesion of organic and inorganic material in thermal production. The comprehensive laboratory testing and field data from the SAGD wells shows that EN-coating significantly improves the well integrity in the harsh thermal production environment.
Effect of Squeeze Treatment Stages Mixing During Injection on Lifetime
Authors: Vazquez Oscar , Mackay Eric , Raga Manuel , Ross Gill
Published: June 2018

Scale inhibitor squeeze treatments are used to prevent scale deposition in production wells. A treatment consists of injecting a scale inhibitor slug at a concentration between 5 and 15%, referred to as the main treatment, followed by an overflush, which will push the chemical slug deeper into the reservoir. During injection, the stages might undergo some degree of mixing in the tubing. This paper addresses the impact such mixing would have on the squeeze lifetime. A consequence of mixing between main treatment and overflush stages in the well tubing would be that although the same overall mass of scale inhibitor was injected, it would be distributed over a larger volume of water and therefore be exposed to the rock formation at a lower concentration than planned in the design. The degree of mixing in the tubing depends on a number of factors, such as tubing length and diameter, and the pumping rate. The phenomenon is described by the longitudinal dispersion coefficient, which may be calculated.

The resulting calculation may be defined as the spreading of a solute along the longitudinal axis, which leads to the spread of an initial high concentration slug with a low spatial variance to a final stage of low concentration with high spatial variance. The main objective of the paper is to study the effect of the degree of mixing of the main and overflush stages on the squeeze treatment lifetime. The net effect of full mixing would be that instead of there being two different stages at very different scale inhibitor concentration, a single stage at a lower concentration might be exposed to the rock formation. Two mixing profiles were considered, a short and long tubing; where the total injected volume is greater than and less than the total tubing volume, respectively. A number of levels of mixing were considered and compared to the base case, where no mixing was allowed. The results showed that squeeze lifetime is not significantly reduced if mixing occurs in a short tubing interval, whereas it can be reduced by up to 20% in a longer tubing interval.
Simulation of Squeeze Treatment/Tracer Programme Designs
Authors: Vazquez Oscar , Giannakouras Ilias , Mackay Eric
Published: June 2018

One of the biggest challenges in designing squeeze treatments is ensuring appropriate chemical placement along the completion interval. Generally, the chemical slug is bull-headed; therefore, in long horizontal wells and/or crossflow wells, exposing the chemical to all the completion intervals might be difficult. In this paper we introduce a method to evaluate placement efficiency. If placement is inadequate, some sections of the well will be unprotected, resulting in an undesirable situation: the well may appear to be protected because the inhibitor return concentrations measured at surface are above the threshold, but there is a loss of production due to scale deposition in areas of the well not contacted by chemical. In these circumstances inhibitor placement can be accurately determined by production logging, but this can be prohibitively expensive. An alternative is to use tracers to evaluate the layer flow rate distribution, and therefore quantify chemical placement. The objective of this paper is to determine if a tracer package could be deployed as part of a squeeze treatment in challenging wells, in particular in the overflush stage. If there are zones in the wellbore at different pressures, then producing the tracer back in steps at different rates will result in the tracer return concentration profile having characteristic features that can be interpreted to estimate chemical placement.

Two three layer cases with crossflow are considered. In both cases, a tracer package was included in the overflush, and the resulting return profiles showed clearly the desired features. The main advantage of this approach is that there is no significant increase in the operational expense. The only additional expense will be the cost of the specific tracer and the subsequent analysis. It is envisaged that the cost is less than 5% of the total squeeze treatment cost. The results of this novel multi-rate post squeeze production stage following injection of tracer demonstrate the feasibility of including such a tracer package in a squeeze treatment. Data collected may then be used to optimise the design of subsequent treatments, to ensure that appropriate placement is achieved by rate control or by diversion, if necessary.
Extending Reservoir Knowledge from the Produced Data
Authors: Ishkov Oleg , Mackay Eric
Published: June 2018

Understanding the reservoir connectivity advances engineering and management decisions and enhances overall field performance. A method to investigate injector to producer connectivity from an identified proportion of the injected brine in the produced water is proposed.

Chloride, sodium, boron and lithium are ideal tracers: typically they do not participate in geochemical reactions. These ions track injection water without retardation, and if their concentration differences with formation brine are high enough to overcome measurement errors, then they may be used as indicators of the mixing ratio between injection and formation brines. This paper proposes the use of this mixing ratio to distinguish brines and to calculate the normalised contribution of injected water in the cumulative produced water volume. A producer to injector connectivity plot allows engineers to categorise the pressure support for production wells in one plot.

This approach was applied to North Sea field data. A mineral scaling risk analysis was performed using the Injector Contribution characteristic plot. Wells being supported by commingled injected seawater and aquifer water were most at risk of BaSO4 precipitation. Historic data for a field case were analysed to examine potential scaling regimes. A set of well candidates for enhanced oil recovery to reduce residual oil in the oil leg was also identified. Most of the water produced in these wells came from injectors, rather than from the aquifer. Those wells have good communication throughout the oil leg and as a result quick water breakthrough occurs. As well as resulting in an early onset of BaSO4 scaling, an Enhanced Oil Recovery (EOR) chemical that is injected would more quickly reach the producers and therefore the potential for chemical EOR applications can be measured. This suggested metric helps to identify that other wells do not experience much seawater production, but are more strongly supported by the aquifer, and so there would be no apparent benefit in reducing residual oil by injecting chemical. This set of wells might benefit potentially from infill drilling nearby, or conformance control methods.

The proposed technique does not require additional sampling to be performed over and above the measured historical produced water compositions that are routinely collected by operators during offshore production for scale management purposes. The analysis to select well candidates for EOR or areas for infill drilling is significantly more challenging using a conventional approach, and we propose that this novel metric of "Producer to Injector connectivity" will be beneficial for the decision making process.
Effect of Test Approaches & Conditions on Corrosion Inhibitor Screening
Authors: Thomson Hunter , Carpenter Ian , Madjitey Rodney , Simpson Caroline , Graham Gordon M. , Frigo Dario M.
Published: June 2018

Laboratory-based assessments of corrosion inhibitors for chemical qualification generally rely on approaches designed to replicate all key aspects of the corroding environment (ppCO2, field crude, brine composition, system temperature, pressure, wall shear, etc.). However, the time and costs associated with testing under fully field representative conditions (e.g. High Pressure/ High Temperature (HP/HT) autoclave or flow loop tests), often restrict the use of such tests to chemicals at dose rates pre-qualified by simpler screening tests, especially when many different formulations are submitted for potential qualification.

This paper includes illustrative examples of how apparently small changes to the test methodology in these preliminary screening tests can have significant influence on the relative ranking and absolute performance of the chemicals tested, specifically:

the effect of pre-corrosion; adjustment of brine chemistry to avoid artefacts from scale deposition; appropriate pH control (representative of the in situ field conditions where high ppCO2 may be present) partitioning between hydrocarbon and aqueous phases can be affected by minor procedural differences.

The net effect is that product ranking can be significantly affected, potentially leading to the qualification of less effective products, or more significantly to the de-selection of otherwise effective products, prior to the more detailed field representative autoclaves / flow loops. More so, since many of the artefacts can be transferred from the screening tests to the field representative tests, product performance and ranking in the more field representative HP/HT tests can also be affected, if critical control of the test conditions is not adhered to.

Examples are provided from both generic corrosion inhibitor formulations as well as case studies using field specific formulations. This will assist in improving the design of corrosion inhibitor screening programs and eliminating common errors and artefacts.
Assessment of the Equivalent Sandbed Roughness and the Interfacial Friction Factor in Hole Cleaning With Water in a Fully Eccentric Horizontal Annulus
Authors: Bizhani Majid , Kuru Ergun
Published: June 2018

In this study, we have investigated the turbulent flow of water over the sandbed deposited in a horizontal eccentric annulus. The primary objective was to determine the effect of the presence of a sandbed on the parameters strongly involved in the bed-erosion process, such as the local fluid-velocity profiles near the interface, the equivalent sandbed roughness, and the average and the interfacial friction factors. The particle-image-velocimetry (PIV) technique was used to measure the velocity distribution at the water/sandbed interface. The bedload transport of particles caused an abrupt increase in the equivalent sandbed roughness. Analyses of the velocity profiles in the wall units confirmed that the sandbed roughness is variable and can be several times greater than the mean particle size. The interfacial ( fi) and the average friction factors ( fa) were evaluated and compared with flow under the stationary-bed and the bedload-transport conditions. The interfacial friction factor increased dramatically at the onset of the bed erosion. We have also found that depending on the bed height (or the surface area of the bed at the interface), the interfacial friction factor can be significantly different from the average friction factor. The results presented here provide much-needed experimental data for the validation of the mechanistic, semimechanistic (empirical), and numerical [computational-fluid-dynamics (CFD)] models of the bed erosion process. The major conclusion of the study is that the difference between the average and interfacial friction factors should be taken into account for more-realistic multilayer modeling of the hole cleaning.
Manure and Residue Inputs Maintained Soil Organic Carbon in Upper Midwest Conservation Production Systems
Authors: Weyers Sharon L. , Johnson Jane M.F. , Archer David W. , Gesch Russ W. , Forcella Frank
Published: June 2018

Core Ideas

Management potential to enhance sustainability was evaluated through change in SOC.

Manure application stabilized but did not increase SOC in organic systems.

Loss of SOC was prevented with manure and high residue inputs.

Conservation production systems are needed in the upper Midwest to slow soil and nutrient loss through tillage‐induced erosion. However, producers are reluctant to adapt no‐till strategies because of the cool‐wet climate. With focus on strip‐tillage (ST) and a diverse 4‐yr (4y) crop rotation as alternatives to no‐till, we assessed eight integrated strategies under both conventional (CNV) and organic (ORG) management. These included conventional moldboard plow + disk tillage (CT), with (YF) fertilizer or manure, with no (NF) amendments, and 2‐yr (2y) rotations: ST‐YF‐4y, ST‐NF‐4y, ST‐YF‐2y, ST‐NF‐2y, CT‐YF‐4y, CT‐NF‐4y, CT‐YF‐2y, and CT‐NF‐2y. Temporal change and loss rates of total soil organic C (SOC) and N (SON) were measured using the equivalent soil mass method for the 0‐ to 30‐ and 0‐ to 60‐cm profiles. Soil was sampled in autumn, after harvest and before tillage, in the first, second, sixth, and eighth years of rotation between 2002 and 2009. In 2002, management had no effect on baseline measurements. Average SOC and SON from 2002–2009 were significantly greater in YF strategy systems, with no other differences among strategies occurring. Net loss in SOC, but not SON, occurred over time, and estimated rates of loss were significant for all individual management strategies, but not all integrated strategies. Under CNV, estimated rates of loss were significant in all but the CNV‐CT‐NF‐2y system. In contrast, under ORG, estimated rates of loss were significant only for ORG‐CT‐NF‐4y and ORG‐ST‐NF‐4y systems. Animal manure, particularly in combination with high residue inputs, had a positive impact for maintaining SOC.
Acute postoperative compartment syndrome in a child receiving patient‐controlled analgesia and peripheral nerve block
Authors: Ryan Sarah , Wiseman Patrick , Mannion Stephen , O'Sullivan Michael
Published: June 2018

Patient‐controlled analgesia and nerve blocks have been implicated in the delayed or missed diagnosis of acute compartment syndrome. We report a case of early successful diagnosis of acute compartment syndrome in a 15‐year‐old male, who received both morphine‐based patient‐controlled analgesia and a femoral nerve block following corrective surgery for patellofemoral instability. Our case demonstrates that multimodal analgesia, combining both patient‐controlled analgesia and a nerve block, does not necessarily prevent the early diagnosis of an evolving compartment syndrome. There must be a high level of clinical awareness amongst medical and nursing staff regarding the serious potential complication of postoperative compartment syndrome and ongoing vigilance to monitor for its symptoms and signs.
Sources of recruitment at foreign commercial banks in Jordan and their impact on the job performance proficiency
Authors: Lutfi Al-Khasawneh Akif , Mahmoud Malkawi Nazem , Ayed AlGarni Abdulla
Published: June 2018

The purpose of this study was to identify sources of recruiting as practiced by the foreign commercial banks operating in Jordan and their impact on job performance proficiency. Six foreign banks were chosen randomly, 160 questionnaires were distributed to employees from the human resource departments at these banks, 121 valid questionnaires were recovered – 76% – and statistically analyzed. Results revealed the highest level of using internal recruitment sources related to accelerating promotion. External recruitment sources related to online ads and attracting distinctive graduates. There is an impact of overall internal recruitment sources on job performance proficiency. There is no impact of the overall external recruitment sources on job performance proficiency, except external recruitment sources related to recommended employees, educational institutions, and training centers, which have impact on job performance proficiency.The study recommended to maintain the application of promotion strategies by acceleration as a source of internal employment, because they positively influence the increase in the level of performance among the employees. Maintain the follow-up of graduates at universities to attract the first of them as a source of employment, maintain contact with the training centers and select the distinguished trainees as the sources of employment, and diversify advertising methods to attract talent.
Transparency of the budget process as a prerequisite for financial decentralization in Ukraine
Authors: Shkolnyk Inna , Melnyk Tetyana , Mershchii Borys
Published: June 2018

The introduction of a qualitatively new type of relationship between citizens and authorities, one in which every person would be guaranteed real observation and protection of the rights and freedoms in these bodies activity, should be one of the priority areas of socio-political transformation in Ukraine. The urgency of the improving local finances, the formation of local budgets and the use of their funds is increasing due to changes in local self-government.
The article proposes a scientific methodological approach to assessing the level of financial decentralization in Ukraine during the period of the decentralization reform (2014–2017). The universal integral indicator of financial decentralization has been calculated, which has found that local budgets improve public funds management, which is illustrated by the growth of the integral indicator level in dynamics.
A number of recommendations are also provided for improving the budget process transparency for each of the components: budget information openness, the state and effectiveness of budgetary supervision, and public participation in the budget process. The idea of the relationship between the budget process transparency and the results of the financial decentralization reform is proposed.
Determinants of consumer retention strategies for telecom service industry in Central India
Authors: Sharma Vinod , Joseph Sunny , Poulose Jeanne
Published: June 2018

The telecommunication industry has witnessed a tremendous growth in recent times in India. It has not only been limited to voice calls, but also integrated into every aspect of human life. This has resulted in the rapid rise of market players, offering innovative products and services. In this changing scenario, we have tried to design and check a model of various factors such as loyalty, satisfaction and switching barriers (customer relationship management, alternative attractiveness and switching cost) influencing consumer retention strategies in Indian telecom service industry.
A structured and undisguised questionnaire and a convenient sampling method have been used to collect the data from respondents from three most populous cities (Indore, Bhopal, and Ujjain) of Central India. Around 450 questionnaires were distributed, out of which 318 usable responses were received for final analysis. The instrument was checked for validity and reliability before the data was analyzed. The hypotheses were tested through Structure Equation Modelling (SEM) for direct effect, and Multiple Moderating Regression Analysis (MMRA) for moderating effect.
The results suggested that loyalty, satisfaction, switching barriers and customer relationship management are positively related and have a direct influence on consumer retention, but the relationship with alternative attractiveness has been found weak. Switching cost, as moderating variable, was found to be very effective and showed significant deviation in the relationship between independent and dependent variables.
Design and Synthesis of Benzopyranopyrimidinyl Phosphonates as Cytotoxic and Antioxidant Agents
Authors: Santhisudha Sarva , Mohan Gundluru , Rani Tenkayala Sobha , Reddy Peddaiahgari Vasu Govardhana , Reddy Cirandur Suresh
Published: June 2018

Background:

A concatenation of bioactive diethyl(2-hydroxyphenylsubstituted) benzopyrano pyrimidinyl phosphonates were synthesized under eco-friendly green conditions in the presence of palladium doped graphitic carbon nitride (Pd@g-C3N4) as catalyst.

Methods:

he title compounds were evaluated for cytotoxic activity against MCF-7, SW-480, HeLa and HL-7702 cell lines and in-vitro antioxidant activity by DPPH, NO and H2O2 methods.

Results:

he synthesized compounds manifested robust cytotoxic and antioxidant activities.

Conclusion:

Some of them showed much higher bioactivity than the standards.
Synthesis and Investigation on the Antidiabetic Effect of 3-aryl-1-(5-methylisoxazol-3-ylamino)-1-(4-nitrophenyl) Propan-1-one
Authors: Liu Jinyu , Zhou Zuwen , Liu Jian , Yan Jufang , Fan Li , Tang Xuemei , Liu Jie , Chen Feifei , Yang Dacheng
Published: June 2018

Background:

Diabetes mellitus is the third-largest non-communicable chronic disease
worldwide. There are many effective drugs, but the long-term use of these clinical drugs may cause
various side effects. Therefore, it is urgent to develop new antidiabetic molecules with higher efficacy
and lower toxicity.

Methods:

Fifteen new 3-aryl-1-(5-methylisoxazol-3-ylamino)-1-(4-nitrophenyl)propan-1-one were
synthesized directly through the Mannich reaction of 4-nitroacetophenone, 3-amino-5-
methylisoxazole and aromatic aldehydes catalyzed by concentrated hydrochloric acid. The molecular
structures of the products were fully characterized by 1H NMR, 13C NMR, ESI MS and HRMS.
The peroxisome proliferator-activated receptor (PPAR) response element and α-glucosidase inhibitory
activity of these compounds were evaluated in vitro. Molecular docking, molecular physical
parameters calculation, and molecular toxicity prediction were performed to analyze the structure-
activity relationship and evaluate the druggability of these compounds theoretically.

Results:

All compounds exhibited weak antidiabetic activities, but compound 15 showed promising
as a high performance, dual-target antidiabetic lead compound with peroxisome proliferatoractivated
receptor (PPAR) response element relative agonist activity of 99.55% at 27.2 nmol·mL−1
and α-glucosidase inhibitory activity of 35.21% at 13.6 nmol·mL−1. All compounds obtained may
have no cardiotoxicity, no acute toxicity, no carcinogenic, and within safe range of mutagenic risk.

Conclusion:

This study identified a potential PPAR lead molecule and presented an unusual strategy
for antidiabetic drug development.
Enantioselective Plasma Pharmacokinetic Study of a Novel Anti- Sichistosomiasis Agent P96 in Rat by Liquid Chromatography-tandem Mass Spectrometry
Authors: Meng Ran , Zhang Danlu , Ji Jianbo , Hu Lingyun , Sun Dequn , Wang Haina
Published: June 2018

Background:

2-Cyclopentanecarbonyl-1,2,3,6,7,11b-hexahydro-pyrazino[2,1- a]isoquinolin-
4-one (P96), was found to be a novel drug candidate with one chiral center to treat schistosomiasis
caused by Schistosoma japonicum.

Objective: To study pharmacokinetic characteristics, a simple, rapid and sensitive liquid chromatography-
tandem mass spectrometry (LC-MS/MS) method was developed and fully validated for the quantification
analysis of P96 in rat plasma.

Methods:

Chromatographic separation was performed on a C18 column with gradient eluted mobile
phase composed of acetonitrile and water at a flow rate of 0.5 mL/min. Detection was performed on a
triple-quadrupole tandem mass spectrometer using positive mode electrospray ionization in the multiple
reactions monitoring (MRM) mode.

Results:

Excellent linearity was observed in the range of 3-900 ng/mL with the lower limit of quantification
of 3 ng/mL in rat plasma for P96. The intra- and inter-day precisions exhibited less than 6.6%.
Mean recoveries ranged from 96.9% to 102.4%. This method was applied to investigate the enantioselective
differences on the pharmacokinetics between (R,S)-P96 and its enantiomers in rats after oral
administration. The enantioselective differences of (R)-P96, (S)-P96 and (R,S)-P96 were found and
compared.

Conclusion:

The established method was found to be accurate, precise, and sensitive and can be applied
to investigate the stereoselective differences on pharmacokinetics between rac-P96 and its enantiomers.
Oral Aspects Identified in Atopic Dermatitis Patients: A Literature Review
Authors: Oliveira Aline Domingues Tavares , Sodré Camila Stofella , Ferreira Dennis de Carvalho , Abad Eliane de Dios , Saintive Simone , Ribeiro Márcia , Cavalcante Fernanda Sampaio , Piciani Bruna , Gonçalves Lucio Souza
Published: June 2018

Introduction:

Atopic dermatitis is a chronic inflammatory skin condition that is more prevalent in children (10-20% of the world's population) than in adults. As its etiology is multifactorial, it is important to know the most frequent oral manifestations in atopic dermatitis patients.

Methodology:

In the last decades, the correlation between atopic dermatitis and conditions and/or changes in the oral cavity has been demonstrated by several studies. The objective of this paper was to describe, through a review of the literature, the oral health conditions and/or oral aspects identified in patients with atopic dermatitis.

Search Strategy:

A descriptive literature review was carried out through a bibliographical survey based on the last 10 years, in order to answer the study questions.

Results:

As a result, we found six studies with different sample sizes, ranging from 43 to 468 patients, and the majority of them were of cross-sectional study design.

Discussion:

Two studies performed their analysis through dental exams and reported that patients with atopic dermatitis tend to have a greater frequency of carious lesions, and two studies correlatedCandidawith atopic dermatitis through mycological analyzes.

Conclusion:

There are a few studies in the literature that identify the oral aspects of atopic dermatitis. More investigations are needed in order to contribute to the knowledge of such oral aspects and the approach to treat these patients regarding oral health.
Treatment Outcome and Adverse Events of Tenofovir Disoproxil Fumarate Based Regimens as Compared to Zidovudine Based Regimens Among People Living with HIV/AIDS: A Systematic Review and Meta-Analysis of Observational Studies
Authors: Kefale Adane Teshome , Dadi Tegene Legese , Biru Tessema Tsehay , Mega Teshale Ayele
Published: June 2018

Background:

Findings from different studies report inferior clinical and virologic efficacy with TDF/3TC/NVP. But, some studies show that, there was no statistically significant difference in mortality among ZDV and TDF based regimens. The objective of this review was to systematically identify, appraise and synthesize the best available evidence on efficacy and safety of TDF based regimen as compared to ZDV based regimens.

Methods:

A three-step search strategy was used to locate published and unpublished studies. First, an initial limited search of google was undertaken followed by analysis of text words. A second extensive search was undertaken. We searched the PubMed, EMBASE, Google Scholar, Medline, and CINHAL. We did the initial search for articles on July 11-18, 2016, and updated the results on May 13, 2017.Third, the reference lists of all identified articles was searched for additional studies.

Results:

ZDV based regimens had better outcome on prevention of mortality (OR=1.31, 95%CI (1.14, 1.50), I2= 0%, Chi2= 2.51), and lower virologic failure (OR = 1.44, 95% CI [1.18, 1.76], chi2= 5.91, P= 0.003, I2=83%) while, TDF based regimens were more tolerable (OR=0.15, 95%CI (0.08, 0.30), I2= 40%, Chi2= 3.31). The difference in incidence of opportunistic infection is not significant (OR = 0.83, 95% CI [0.52, 1.32], chi2= 0.11, P= 0.42, I2=0%).

Conclusion:

There is lower mortality and lower virologic failure in ZDV group, but better safety profile among TDF based regimens.
A Wearable System for the Stress Monitoring of Air Traffic Controllers During An Air Traffic Control Refresher Training and the Trier Social Stress Test: A Comparative Study
Authors: Rodrigues Susana , Paiva Joana S. , Dias Duarte , Aleixo Marta , Filipe Rui , Cunha João Paulo Silva
Published: June 2018

Background:

Air Traffic Control (ATC) is a complex and demanding process, exposing Air Traffic Controllers (ATCs) to high stress. Recently, efforts have been made in ATC to maintain safety and efficiency in the face of increasing air traffic demands. Computer simulations have been a useful tool for ATC training, improving ATCs skills and consequently traffic safety.

Objectives:

This study aims to: a) evaluate psychophysiological indices of stress in an ATC simulation environment using a wearable biomonitoring platform. In order to obtain a measure of ATCs stress levels, results from an experimental study with the same participants, that included a stress-induced task were used as a stress ground truth; b) understand if there are differences in stress levels of ATCs with different job functions (“advisors”vs“operationals”) when performing an ATC Refresher Training, in a simulator environment.

Methods:

Two studies were conducted with ATCs: Study 1, that included a stress-induced task - the Trier Social Stress Test (TSST) and Study 2, that included an ATC simulation task. Linear Heart Rate Variability (HRV) features from ATCs were acquired using a medical-grade wearable Electrocardiogram (ECG) device. Self-reports were used to measure perceived stress.

Results:

TSST was self-reported as being much more stressful than the simulation task. Physiological data supports these results. Results from study 2 showed more stress among the “advisors” group when comparing to the “operational” group.

Conclusion:

Results point to the importance of the development of quantified Occupational Health (qOHealth) devices to allow monitoring and differentiation of ATCs stress responses.
Mudharabah Hasil Pertanian Di Tinjau Dari Undang Undang Dan Hukum Islam
Authors: Ash Shidiqie Jannahar Saddam
Published: June 2018

This research aims to analyze the implementation of profit sharing agreement for paddy field in Gamping Sub-district using Law No. 2 of 1960 and Islamic Law. The conclusion of this study are: The implementation of profit sharing agreement for paddy fields in Gamping Sub-district is not fully in accordance with the Law No. 2 of 1960 and the Islamic law. The agreement of profit sharing in Gamping Sub-district in general is conducted orally, based on trust, and without any witnesses. The balance of profit sharing used in general is "maro" (½ part for sharecroppers and ½ part for owner) with all the production costs borne by the sharecroppers. In the event of crop failure, it becomes the risk borne by the sharecroppers. The crop yields reaching specific nisab or limit in general are not directly paid for the zakat. The obstacles to implement the Law No. 2 of 1960 and the Islamic Law in Gamping Sub-district are because there is no socialization from any parties related to Law No. 2 of 1960 and the Islamic Law in agricultural cooperation, here is hereditary habit, the owners and sharecroppers do not want to use complicated procedure, the owners have been good enough and fair with the common system used, and the sharecroppers accept the habit in force although they feel that it is hard and unfair. The bargaining position between the owner and sharecroppers at Gamping Sub-district is devided into three phases: in the past, the number of sharecroppers was more than the number of owner; currently, the number of sharecroppers is declining; and in the future, the sharecroppers  will be lesser than the number of owner so these will increase  the bargaining position of the sharecroppers (it is the answer to implement Law No.2 of 1960 and Islamic Law.
Memahami Konsumsi Islami Upaya Meningkatkan Produk Pembiayaan Mudharabah di Bank Syariah
Authors: Mulato Tri
Published: June 2018

Perbankan syari’ah saat ini telah memiliki payung hukum yang kuat dengan hadirnya undang-undang nomor 21 tahun 2008 tentang perbankan syari’ah. Hal ini sangat berpengaruh terhadap eksistensi dari perbankan syari’ah yang semakin diminati oleh banyak kalangan. Bank syari’ah dikenal dengan konsep bagi hasil. Hanya saja produk bank syariah khususnya pada produk pembiayaan tidak semua menggunakan bagi hasil. Produk pembiayaan jual beli murabahah menjadi lebih dominan dibanding produk bagi hasil pembiayaan mudharabah. Kontribusi dari total pembiayaan di bank syariah mudharabah yaitu 6,558 persen atau 14.590.000.000.000, sedangkan pembiayaan dengan akad jual beli murabahah mencapai 61,663 % atau sebesar 137.193.000.000.000. Hal ini membuktikan bahwa bank syariah masih dominan menggunakan pembiayaan dengan akad jual beli. Bank syariah diharapkan bisa mengembangkan produk pembiayaan mudharabah maka bank syariah harus memahami dan mengetahui pola kebutuhan masyarakat dan konsumsi yang islami. untuk mencapai market share yang baru menembus 5 persen. Penulisan ini menggunakan jenis deskriptif kualitatif, Batasan dalam tulisan ini difokuskan pada produk pembiayaan mudharabah di bank syari’ah dan pola konsumsi islami. Tulisan ini menggunakan studi pustaka kajian dari berbagai sumber. Untuk meningkatkan volume produk pembiayaan mudharabah perlu memahami konsumsi yang islami. Hasil dari tulisan ini bahwa periode desember 2015 sampai oktober 2016 produk pembiayaan mudharabah di bank syariah mengalami penurunan sebesar -1,552 persen. Pola konsumsi islami memiliki banyak faktor dan bisa memberi pengaruh terhadap peningkatan produk pembiayaan mudharabah di bank syariah. Sehingga bank syariah perlu memahami konsumsi islami serta kebutuhan masyarakat dalam upaya meningkatkan potensi pengembangan produk pembiayaan mudharabah di bank syariah. Potensi pengembangan produk pembiayaan mudharabah di bank syari’ah masih sangat besar.  Potensi pengembangan produk pembiayaan mudharabah masih sangat besar dan sangat luas.

 

Kata Kunci : Konsumsi Islami, Produk Pembiayaan Mudharabah, dan Bank Syariah.
Rasionalitas dalam Ekonomi Islam
Authors: Ngasifudin Muhammad
Published: June 2018

Islamic world view of the economy is based on a paradigm that justifies the social economy as its objectivity foundaton, by positioning the race on pole position than individual interests (self interest). according to the view of conventional economic, this case is extremely irriational and does not meet the requirements of transitivity. while the islamic economic rationality can be known on the principles of islamic economics and the basic principles of the system which can be owned.
Analisis Faktor yang Menjadi Alasan Nasabah Memilih Deposito Mudharabah di BPRS XYZ
Authors: Satyarini Julia Noermawati Eka
Published: June 2018

 This research aims to explain what factors into the reasons customers choose deposit in BPRS XYZ and the sample used is that customers save their money in the form of deposit. There were 33 questionnaires from respondents who may be samples of research and then use Chocran Q Test method to analyze the data. Based on the result of the research can be conclude that customers who deposit fund in the form of deposits have different reason factor. It this can be seen from the result of acalculation that shows Q countdown (36.00) > Q table (12.592) which means refused table Ho. And the results can also be seen that the most dominant factor is the factors owned by customers and security service with the same percentage (93.94).