bluuebunny/crossref_metadata_2025 huggingface dataset:
Electric Prospecting Will Help
Authors: Geletii P. P.
Published: October 2016

With the development of science and technology geophysical methods of prospecting and mineral exploration have changed a little. Owing to reliable equipments, designed by modern technologies, field observations have become more accurate and owing to a powerful mathematical apparatus of modeling and interpretation, as well as software, the final geophysical data has gained perspective, faithfulness and informative value. But, at the same time, requirements to geophysical information have changed, as well as cost of work which under the conditions of oil crisis is not entirely acceptable. Another important point is that "geophysical evolution" lies in perfection and modeling of old ideas, physical essence of the methods and approach to an observation system construction, as well as the measuring principle have practically remained the same. I am falling under the impression that such methods of geophysical exploration as electrical prospecting and magnetic survey the world has completely forgotten. In essence, it does make some sense, as it is very difficult to compete with information obtained as a result of seismic exploration. But, is it always beneficial and necessary to use such expensive work? The experience in geophysical practice tells us that this question has an unambiguous answer: alternative solutions are possible nearly always.

This article describes one of such alternative solutions, i.e. a method of directional electromagnetic reception. This method was developed by analyzing already–existing methods of Applied Electric Logging, by examining their physical nature, equipments in use, methods of field observations, the efficiency and faithfulness of the information being obtained, problems and shortcomings, as well as a field of application.

The aim of this work involves drawing attention of the oil world to new methods of geophysical exploration, which are full methods of Applied Geophysics, have a number of advantages and are relatively cheap in comparison with the methods used today.

The article is organized in such a way that the reader is given an opportunity to consistently get acquainted with the method and then to find out its actuality and to draw certain conclusions, no matter whether he is a specialist in the field of geophysics, or not.
Validating Mixing Models for Dielectric Logging
Authors: Kouchmeshky Babak , Fanini Otto , Nikitenko Marina
Published: October 2016

An important element of dielectric logging is validating the mixing models that can predict a formation's electromagnetic response over a wide frequency range. The main petrophysical outputs from dielectric log interpretation include water saturation and water resistivity. The resistivity of water as an output of the interpretation provides an advantage for formations where this information is not available or varies over short depths.

The electromagnetic properties of a formation show a variation with respect to frequency that is called dispersion. To relate the dispersive behavior of a formation to petrophysical properties, certain mixing models are used that relate the properties of the aforementioned elements of the rock to that of their collective effective behavior. Interpretation success depends on the application of a suitable mixing model. This work provides a comparative study of different mixing models and their validation with respect to experimental results on sand and carbonate rocks.

Results of experiment on dielectric dispersion of rock cores are used to study the performance of commonly used mixing models. Experimental results for various values of water saturation and water resistivity at different frequency ranges are used in pursuing two goals. First, the ability of the mixing models to recreate the rocks' dielectric dispersive behavior is considered. It is shown that selecting an appropriate mixing model requires experimental data on a wide frequency range. Second, the fitted mixing models are used to invert for petrophysical parameters. These parameters are compared with known values from experiment to quantify the error associated with using each mixing model.

Dielectric Logging service is poised to play an important role in Formation Evaluation of unconventional and/or non-Archie environments, only if appropriate mixing models are developed and applied. Paper provides guidelines on choosing the appropriate mixing model to improve accuracy of dielectric data processing.
New Life for Old Fields: Identification of Bypassed Productive Zones, Formation Evaluation and Formation Testing Through Casing with Modern Wireline Tools
Authors: Zozulya A. , Petrakov Y. , Karpekin Y. , Blinov V. , Weinheber P. , Karipov I.
Published: October 2016

The Volga Urals basin of Western Russia has a very long production history and consequently many of the original target reservoirs have become depleted. The Uzenskoe field is no exception. Originally placed on production in 2008 the original target layers in the lower Cretaceous formations have since depleted. It was assumed that potentially productive reservoirs exist in the overlying layers; however, these had never been evaluated. Using a variety of through-casing measurements these layers were investigated for productive potential. Integrated interpretation of the acquired data was used evaluate lithology, rock composition, saturation and porosity to identify potentially productive layers. These layers were then perforated and tested with a wireline conveyed formation tester inside casing. Fluid type was verified, samples were acquired and pressure transient analysis was performed to determine layers permeability. The entire evaluation took less than three days of rig time comparing very favorably with alternative methods.

In this paper we discuss the planning, execution and interpretation of this evaluation exercise.
Competent Utilization of Multistage Acid Fracturing Technology to Increment Well Productivity during Stimulation of Low Permeability Gas Carbonate Reservoirs – Case Study
Authors: Guizada Pablo
Published: October 2016

Tight gas reservoirs and specifically low permeability gas-bearing carbonate formations require stimulation to produce commercial gas rates. Certain carbonate reservoirs in Saudi Arabia are highly heterogeneous and the degree of heterogeneity changes over the field and within well drainage areas. Horizontal multi-stage acid fracturing technology has become the preferred completion method in such reservoirs to stimulate these carbonate formations to maximize reservoir contact and enhance well productivity. Due to the degree of heterogeneity of these formations, a number of factors should be considered and a set of best practices should be implemented to overcome the reservoir challenges and achieve the expected results.

Maximizing stimulated reservoir volume is one of the key aspects of the success of this technology. To maximize the stimulated reservoir volume, effective placement of the hydraulic fractures for every stage must be achieved, which is one of the most challenging factors. Effective placement of hydraulic fractures depends mainly on the following factors: placement of the horizontal wellbore along the minimum-stress direction and proper annular isolation to induce independent fractures across each stage. This goal becomes even more challenging to achieve with acid fracturing treatments. Failure to isolate the stages can lead to hydraulic communication between the fracture stages, allowing the pumped frac stage to propagate to the previously open frac stage, preventing the creation of separate fractures, affecting the well's productivity and ultimate recovery. A second factor that governs multi-stage completion effectiveness is the use of swellable packers to ensure proper isolation between the various stages, which was observed in the field.

This paper describes the application of Multi-Stage Fracturing (MSF) completion technology. Field cases describing the deployment of the MSF completions and the obtained results after stimulation is presented, as well as the main conclusions and recommendations for successful implementation of this technology are highlighted.
Maximize Efficiency of Coiled Tubing-Conveyed Perforation with Advanced Gun Deployment System and Real-Time Correlation in High-H2S/High-Pressure Wells
Authors: Panferov Rostislav , Burov Anton , Zhandin Alexander , Ghioca Gelu , Boulter Derek
Published: October 2016

Well completion and commissioning operations offshore present a variety of technical and operational challenges in the quest to maximize well productivity and optimize the economic value together with focus on safety. This is very relevant to the perforation operations performed in hostile and high-pressure reservoir conditions encountered in a complex development project in the Caspian basin. We provide description of the project and the innovative solution applied, including challenges faced, experience gained, and lessons learned.

To overcome challenges, we selected electric-line-enabled (e-line-enabled) coiled tubing (CT) for precise depth control, and the latest advanced gun deployment system for conveyance of long gun strings under pressure. Innovative solutions implemented throughout the project included the perforation-shock-resistant bottomhole assembly (BHA), two independent emergency disconnects, and tuned software to predict and evaluate shock load and dynamic underbalance. Some of the unique technical solutions were designed specifically for this project: high-pressure and H2S-rated connectors; specialized tool deployment stack; 15,000-psi working pressure 5.12-in. ID H2S-rated rounded scallop guns; shock-resistant electrical disconnect; and high-tensile CT logging head disconnect weak points.

To date, more than 10 well commissioning operations were successfully completed with this innovative method—e-line-enabled CT perforation under high pressure. This perforation technique proved to effectively minimize operational time, associated risks, improper equipment use, and footprint on location. Such approach allowed safe and efficient perforation in a controlled well environment that resulted in accurate depth control and managed detonation shock load and overbalanced conditions, which avoided any well fluid influx or H2S release. The developed solution required seamless integration of innovative techniques and hardware, including e-line enabled CT, the CT logging head, the gun deployment system for pressurized well conditions, wireline tools and specialized perforation equipment. The design was optimized to perforate the well in three or four runs at overbalanced condition (squeeze mode) in a single rig-up job instead of more than 20 wireline runs. Additionally, the use of CT granted flexibility and increased operational safety to perform pumping operations for well displacement and well control, injection of H2S scavenger, and stimulation, as per Operator's plan, without or with only partial rig-down.

This is the first time that the described CT perforation operation using such techniques has been performed in the Caspian region. The experience demonstrates a method to safely and efficiently facilitate perforation jobs under challenging conditions in the future.
Successful CT Intervention for Re-Frac on Horizontal Oil Well After 2 Years of Production Completed with Full Bore Liner with Frac Ports Controlled by Shifting Tool
Authors: Mazitov M. R. , Valiullin A. S. , Burdin K. V. , Starodubtseva K. A. , Demenchuk I. A. , Serikov D. A.
Published: October 2016

In 2016 it was received the first experience of Coiled Tubing Intervention for Re-frac on horizontal oil well after 2 years of production completed with full bore MSF liner with frac ports operated by CT shifting tool.

The main tasks for Coiled Tubing service setted by customer were effective wellbore preparation of horizontal oil well after 2 years of continuous production, the following frac ports opening and closing by CT in predetermined order for selective fracturings and final clean out and nitrogen kick-off for getting well into production.
Drilling Waste Reduction During Well Construction in the Fields of LLC LUKOIL-West Siberia
Authors: Khalimova Aliya , Shcherbakov Andrey
Published: October 2016

A group of wells of TPE "Pokachevneftegaz" LLC "LUKOIL-WEST SIBERIA" (given in 2015) were selected as an object of study. A comparative analysis of the volume of drilling waste (DW) formation has brought to light that the actual values exceed the normative values. To determine a reason for the excess is currently difficult due to the absence of accounting of the formation of DW during the process of drilling wells in the fields of LLC "LUKOIL-WEST SIBERIA".

The goal of this research work is to decrease the volume of DW formed during construction of wells in the fields of LLC "LUKOIL-WEST SIBERIA" by setting up controls over the volume of their formation, specifically: carrying out a unique calculation of norms of DW formation for each well when developing the project documentation;accounting the formation of DW during the process of drilling.

An analysis of the effective governing documents (GD) that are used in the calcuation of the norms of DW formation has shown that: the following documents do not take into account the use of modern and effective equipment and drilling solution systems that are used during well construction on the fields of LLC "LUKOIL-WESTERN SIBERIA";the empirical coefficents of the losses of drilling solution due to the use of cleansing systems (CS) found in the GD are outdated and using them is inexpedient.

"Regulation of accounting of drilling waste during drilling wells in the fields of LLC "LUKOIL-WEST SIBERIA" is developed in 2016 in the framework of which: works on the development of forms of calculation of the norms of DW formation were made, coefficients of losses of drilling solution when using CS were established, and actions in regards to accounting of DW formation during the process of drilling wells were suggested. The document is approved and brought into action on 14.3.2016.

A trial calculation of the volumes of DW formation is made for the researched group of wells in compliance with the methodology layed out in the regulation. A comparative analysis in regards to the volumes of DW formation has shown that actual values exceeded that predicated values (using the regulation) by 34.6%. Actions for the introduction of accounting of DW formations should allow correct values for the actual volumes of DW formation to be established during the process of well construction and allow their manipulation in the direction of the normative values.

According to the acquired results, and also data in regards to the volumes of DW formation, an assessment of the economic effectiveness is made and a positive effect is established. The introduction of control over the objects of DW formation should allow for the elimination of heightened unplanned expenditures in the future. On the basis of the regulation calculations of norms of DW formation are made for every well during the preparation of the projection documentation for the well construction since March 2016.
The Kosmos Innovation Model - Using Integrative Processes to Redefine Social Investments for Greater Social Impact in Ghana
Authors: Adashie Ruth , Gyan-Kesse Benjamin , Sarpong George , Boakye-Agyei Kwame
Published: October 2016

This paper examines the Kosmos Innovation model that demonstrates impactful results combining integrative but innovative social investment approaches altogether for an impactful social change.

The Kosmos Innovation model was applied to a set of young entrepreneurs with ICT and Agribusiness background. They went through the three main tenets of the model, which are Collaboration, Incubation and Acceleration. Through observations and analysis, these components were deployed to facilitate connections for knowledge sharing, excite and inspire budding entrepreneurs to use technology as a conduit for development and engage small holder businesses to scale up private sector solutions. Processes are compared and impactful approaches were identified.

This long-term project has just begun but key impact indicators and KPIs on social change, business change and market system changes are beginning to emerge. The goal of investing in one entrepreneur at a time within the innovative but integrated approach of providing collaborative and synergistical platforms, incubation of new ideas and ideals, the acceleration of potential on-going projects have energized stakeholder perceptions about agriculture. Combining the three pronged approach at the same time is creating positive social, business and market changes.

This paper describes the processes and results of the model and discusses the novelty of the new approach and its ability to combine integrative approaches all at the same time, to develop both start-up and small scale entrepreneurs.
Solutions for Management of Oil on Drilled Cuttings in the New Deepwater Oil Province of Ghana
Authors: Mac-Acquaye Victoria , Aidoo Ato
Published: October 2016

The management of residual oil on drilled cuttings poses a major environmental consideration for offshore drilling. Often the methods employed are dictated by regulatory regimes. Where ‘zero discharge’ is specified by regulators then ‘skip and ship’ or ‘cuttings reinjection’ become the primary technologies available. In regulatory regimes where a degree of marine discharge is permitted, the cuttings driers or offshore thermal desorption technologies are used to reduce the % amount of oil on cuttings prior to discharge to the ocean.

Conventional cuttings driers, the technology currently used in Ghana, typically give 3% or more of oil on cuttings by weight of cuttings. Though this is relatively low and tolerable in some jurisdictions, both legislators and operators have a commitment to further reduce discharges in a progressive manner.

Most of Ghana's oilfields fall in deepwater areas and cuttings re-injection methods are not being actively considered in the near term due to less mature deepwater technology and cost. The offshore treatment using offshore thermal desorption offers an alternative method to treat drilled cuttings offshore and reduce the oil concentration on cuttings to typically less than 0.5% by weight prior to marine discharge. An overview of the method is however offered in this paper.

The Skip and ship methods where cuttings are shipped onshore and treated to remove oil on cuttings before being disposed of onshore, is used in other deepwater areas. Special offshore cuttings handling equipment plus a marine and road logistics network as well as onshore treatment infrastructure are required to support such activities.

This paper will look at the relative merits of offshore cuttings treatment by thermal desorption technology compared to skip and ship methods. It will consider the merits of each method in the context of projected Ghana drilling activity, onshore infrastructure requirements and other considerations.
Business Continuity Management in a Dynamic Environment – Lessons From Macondo
Authors: Ajimoko Tayo
Published: October 2016

Business Continuity (BC) is defined as the capability of the organization to continue delivery of products or services at acceptable predefined levels following a disruptive incident. (Source: ISO 22301:2012)

Business continuity management (BCM) is a framework for identifying an organization's risk of exposure to internal and external threats. The goal of BCM is to provide the organization with the ability to effectively respond to threats such as natural disasters or data breaches and protect the business interests of the organization.

The April 2010 Deepwater Horizon (DWH) Macondo blowout resulted in death of 11 people and the US government estimated that approximately 5 million barrels of crude oil was discharged into the ocean. The well was declared officially sealed about 5 months after the blowout. In July 2015, British Petroleum (BP) agreed to pay $18.7 Billion in fines, the largest corporate settlement in US history. This paper will catalogue the major BCM lessons learnt from the incident.

BCM includes disaster recovery, business recovery, crisis management, incident management, emergency management and contingency planning. It is aimed at identifying risk, threats and vulnerabilities that could impact an entity's continued operations and provides a framework for building organizational resilience and the capability for an effective response.

This paper will concentrate on the efficiency and effectiveness of BP's crisis management, disaster recovery and contingency planning in a flux environment in the wake of the disaster. The theatre of the Macondo blowout was set against a backdrop of transitioning internal environment and a changing external environment. Transcripts of media communications, results of emergency response and intervention plans and rationale will serve as pointers for deconstructing BCM plan outcomes.

Observations, conclusions and recommendations from copious volumes of investigation reports reviews and published reports as well as accounts of successful BCM from other landmark blowouts and oil spills in the industry will be employed in distilling the keys lessons that will give any other operator facing such a disaster a head start in future.
Effects of revegetation on soil moisture under different precipitation gradients in the Loess Plateau, China
Authors: Tian Fei , Feng Xiaoming , Zhang Lu , Fu Bojie , Wang Shuai , Lv Yihe , Wang Pei
Published: October 2016

Revegetation can alter catchment water balance and result in soil desiccation. Large-scale revegetation took place in the Loess Plateau of China to control soil erosion and improve environmental conditions. However, the dynamic nature of soil moisture in response to revegetation under different climatic conditions is still unclear mainly due to lack of long-term in situ observations. To overcome this challenge, a biophysically based ecohydrological model (WAVES) was used to examine the effects of revegetation on soil moisture. Results showed that trees consume more water (100% of precipitation) than shrub (97.6%) and grass (98.3%), and therefore are more likely to result in soil desiccation. No runoff occurred under the tree scenario, while for shrub and grass, runoff accounted for 2.4% and 1.7% of precipitation, respectively. In areas with mean annual precipitation (MAP) less than 400 mm, tree planting resulted in soil water deficit, while in areas with MAP exceeding 600 mm, no soil water deficit occurred. Within this MAP range (400 < MAP < 600 mm), this could lead to soil water deficit during dry years. Extending this analysis to the entire Loess Plateau, 40% of the region will face reduced soil moisture when converting cropland to trees.
Analysis of the Influence of Food Colorings in Esthetic Orthodontic Elastomeric Ligatures
Authors: Dias da Silva Vanessa , de Lima Eduardo Martinelli S , Dias Caroline , Osório Leandro Berni
Published: October 2016

Proposition:

The purpose of this study was to evaluate in vitro the color changes of esthetic orthodontic elastomeric ligatures of different shades when exposed to four food colorings commonly found in the diet of patients.

Materials and Methods:

The sample consisted of esthetic orthodontic elastomeric ligatures in the colors pearl, pearl blue, pearl white and colorless, which were immersed for 72 hours in five different solutions: distilled water (control group), coffee, tea, Coca-Cola ® and wine. The color changes of the esthetic orthodontic elastomeric ligatures were measured with the aid of a spectrophotometer, at T1 - as provided by the manufacturer; and T2 - after colorings process.

Results:

The results indicated that the esthetic orthodontic elastomeric ligatures of all initial hues are susceptible to pigmentation. Among the evaluated colors, all changed the finished look and the color of the samples tested. In ascending order, the color of the samples was as follows: distilled water, Coca-Cola®, black tea, wine and coffee.

Conclusion:

The substances that have a greater potential for pigmentation in esthetic orthodontic elastomeric ligatures were black tea, wine and coffee, respectively. All shades of esthetic orthodontic elastomeric ligatures are susceptible to color change.
La capacitación como estrategia de desarrollo turístico para las comunidades: Caso Centro Shuar Tsuer Entsa, Naranjal
Authors: Torres Quiroga Sergio Javier , Barreth Alba Caicedo
Published: October 2016

En la presente investigación se buscó diagnosticar la situación turística en el Centro Shuar Tsuer Entsa, y el progreso de los habitantes shuaras en esta actividad. Este estudio de carácter cualitativo, bajo los métodos lógico y analítico, se analizó el problema desde la conclusión general del comportamiento organizativo, social y económico de los pobladores locales. El objetivo general consistió en formular una estrategia de desarrollo turístico para los habitantes del centro Shuar Tsuer Entsa que sirva para impulsar el turismo sustentable en el lugar. Lo cual antepuso la hipótesis de la preparación de los prestadores de servicio en temas turísticos que aportaría en la organización de la comunidad y desarrollo sustentable del centro Shuar Tsuer Entsa. Como resultado obtenido luego de la aplicación de encuestas a visitantes, se recibió la calificación del servicio recibido y sugerencias en la implementación de servicios; mientras que en las entrevista a los 37 shuaras intervinientes en el servicio al visitante se recopiló información de su percepción del turismo, participación comunitaria, forma de liderazgo, nivel de comunicación, conocimientos relacionados al turismo y medio ambiente y predisposición en capacitarse. El beneficio obtenido del estudio fue esbozar la organización social del centro Shuar Tsuer Entsa, distribución de funciones, lineamiento de normas y gestionar un trabajo directo de atención al cliente a través de la capacitación en diversos temas. Como conclusión y recomendación para los líderes del Centro Shuar se sugirió vincularse con organismos públicos y universidades, que continúen el asesoramiento y socialización de sus productos turísticos bajo las normativas del turismo sustentable.
DRUG-RESISTANT TUBERCULOSIS: RECENT APPROACH IN POLYMER BASED NANOMEDICINE
Authors: Shaji Jessy , Shaikh Mahmood
Published: October 2016

Tuberculosis (TB) had been a leading chronic bacterial infection since decades. Current therapeutic management of Mycobacterium tuberculosis (MTB) is inadequate due to the lengthy course of treatment, drug-related side effects and ill-planned therapy, and these factors can lead to therapeutic failure and the emergence of drug-resistant TB. The Multi-drug-resistant (MDR) TB needs a lengthy course of treatment with second-line antitubercular drugs (ATDs) having higher side effects and cost. The misuse of second-line ATDs may result in extremely drug-resistant (XDR) strain which is very difficult to treat and require high doses of drugs resulting in more toxicity and side effects. This review highlights the need for novel drug delivery for the treatment of drug-susceptible and resistant TB. The characteristics of the nanoparticulate system in ATDs delivery and its approach in the MDR and XDR TB are discussed. The lung is the site of infection in pulmonary TB and the targeted drug delivery to the site of infection helps in achieving increased efficacy with less dose further reducing the side effects and toxicity. The symbiotic association of nanotechnology and pulmonary drug delivery give rise to an efficient inhalable polymer based nanoparticulate system containing ATDs for the better management of drug-susceptible and resistant TB. Various ATDs loaded polymer based nanocarrier systems like Alginate, PLGA, Chitosan and Gelatin nanocarriers are discussed in detail. Thus, this review highlights the current research in pulmonary drug delivery of polymer based ATDs nanomedicine and their importance in control of drug-resistant TB.
IDENTIFICATION AND MOLECULAR CHARACTERIZATION OF BACTERIA HAVING ANTIMICROBIAL AND ANTIBIOFILM ACTIVITY
Authors: Sharma Garima , Dang Shweta , Gupta Sanjay , Gabrani Reema
Published: October 2016

Objective: The aim of the current study was to isolate and identify the bacteriocinogenic strain exhibiting broad range antimicrobial activity and antibiofilm activity from soil of animal farms.

Methods: In the current study, bacterial strains were isolated from soil of twelve different regions of animal farm all over India and screened for antimicrobial activity against Staphylococcus epidermidis, Micrococcus luteus, Pseudomonas fluorescence and Escherichia coli. Antibiofilm ability of these selected strains was checked on preformed biofilm of S. epidermidis and in addition biofilm disruption potential was also determined. The potent bacterial strain was identified at molecular level by 16S ribosomal DNA (rDNA) sequencing.

Results: 30 out of 231 strains isolated from soil were selected on the basis of antibacterial activity against S. epidermidis. One potential candidate (GAS 101) exhibited ≥99% inhibition against S. epidermidis, M. luteus, P. fluorescence and E. coli and also showed antibiofilm activity. GAS 101 16S rDNA sequencing data identified it as Bacillus subtilis. The sequence of B. subtilis was submitted to genbank under accession no. KJ564301.

Conclusion: B. subtilis GAS 101 isolated from soil of animal farm showed the antibacterial activity against all indicator organisms and also displayed antibiofilm activity against preformed biofilm and inhibited biofilm formation of S. epidermidis.
SELF-MEDICATION PRACTICE AMONG CONSUMERS IN SANA’A CITY
Authors: Albawani Sami Mohammed , Hassan Yahaya Bin , Abd-aziz Noorizan , Gnansan Shubashini
Published: October 2016

Objective: To determine the prevalence of self-medication practice and its associated risk factors in Sana’a City.

Methods: A cross-sectional descriptive study was carried out on consumers attending community pharmacies in Sana’a City. A self-administered questionnaire containing open-ended and closed-ended questions was developed and used for this study. Chi-square test and multiple logistic regressions were used in this study.

Results: A total of 400 consumers were involved in this study. The prevalence of self-medication in the past six months was found to be 90.7 % (94.1% of females and 88.3% of males). In Multivariate analysis, chewing khat, smoking, availability of medical services near the residence and the perception about death due to self-medication were significant predictors of self-medication practice. Those who chewed khat were less likely to use self-medication compared to those who did not chew khat (OR= 0.296, CI 95% 0.100-0.882, p= 0.029). Similar results showed that smokers were less likely to use self-medication compared to non-smokers (OR= 0.429, CI 95% 0.206-0.895, p= 0.024). It was also found that those who have medical services near their residence were more likely to use self-medication compared to those who do not have medical services near their residence (OR= 3.022, CI 95% 1.384-6.596, p= 0.006). Moreover, those who did not believe that self-medication leads to death were more likely to use self-medication compared to those who believed that self-medication may leads to death (OR=2.645, CI 95% 1.232-5.681, p= 0.013).

Conclusion: Self-medication practice was high among consumers in Sana’a City. Chewing khat, smoking, availability of medical services near the residence and the respondent perception about the possibility of death due to self-medication was significantly associated with self-medication.
COMPARATIVE STUDY OF RP-HPLC METHOD VERSUS FOURIER TRANSFORM CONVOLUTION CHEMOMETRIC METHODS; AN APPLICATION ON PHARMACEUTICAL BINARY MIXTURES OF CANDESARTAN CILEXETIL-PITAVASTATIN CALCIUM AND CLOPIDOGREL BISULFATE-ROSUVASTATIN CALCIUM
Authors: El Jamal Marwa K. , Gazy Azza A.
Published: October 2016

Objective: A comparative study of smart spectrophotometric chemometric assisted techniques and RP-HPLC for the determination of candesartan cilexetil (CAN)-pitavastatin calcium (PIT) and clopidogrel bisulfate (CLO)-rosuvastatin calcium (ROS), binary co-administered drugs were developed and validated.

Methods: The spectrophotometric chemometric assisted methods included two simple techniques, namely Fourier transform convolution (FF) and ratio spectra of Fourier transform convolution (FFR) methods. FFR is considered as a hybrid divisor ratio spectra method where Fourier functions are applied to divisor ratio signals. The RP-HPLC method involves a rapid separation on a C18 column using a mobile phase consisting of acetonitrile: sodium dihydrogen phosphate (adjusted to pH 2.6 using orthophosphoric acid) in the ratio of 70:30 v/v at a flow rate of 1 ml/min in isocratic mode. CLO and ROS were monitored at 220 nm however CAN and PIT were monitored at 238 nm.

Results: The spectrophotometric chemometric assisted methods proved their ability to quantify each of the studied drugs in their binary mixtures, where excellent percentage recoveries were obtained. FF and FFR method proved to be linear over the concentration range of 10-50 µg/ml for CLO, 4-20 µg/ml for ROS, 8-20 µg/ml for CAN and 2-10 µg/ml for PIT. The RP-HPLC method was able to separate the drugs in the study; retention times were found to be 3.9 min and 14.4 min for ROS-CLO, 4.2 min and 14.5 min for PIT-CAN respectively. The RP-HPLC method was found to be linear in the concentration range of 0.1-0.5 µg/ml for CLO, 0.04-0.2 µg/ml for ROS, 0.5-1 µg/ml for CAN and 0.05-0.1 µg/ml for PIT. System suitability parameters proved that peaks were well resolved from each other.

Conclusion: The spectrophotometric and chromatographic methods were validated according to ICH guidelines. Recovery was found to be in the range of 95.9 %-100.5 % in synthetic laboratory mixtures. The suggested spectrophotometric methods have the advantage over other methods that they do not require a preliminary separation. Statistical analysis between the suggested spectrophotometric chemometric assisted and RP-HPLC methods, using student’s t-and F-test revealed that there is no difference between the applied methods.
RECENT DEVELOPMENT IN ULTRAVIOLET SPECTROPHOTOMETRY THROUGH THE LAST DECADE (2006–2016): A REVIEW
Authors: Lotfy Hayam M. , Saleh Sarah S.
Published: October 2016

Several techniques have been proposed for treatment of spectrophotometric data, with the objective of extracting the largest amount of analytical information from spectra composed of unresolved bands. The instrumental development and analytical applications of UV regions absorption spectrophotometry produced in the last 10 y (since 2006) are reviewed. The methods were classified according to the spectra data used, including zero order absorption, derivative and ratio amplitudes. The proposed methods were applied to solve different complex pharmaceutical mixtures and the obtained results were accepted when compared to other reported methods. 
CYTOTOXICITY OF CLINACANTHUS NUTANS EXTRACTS ON HUMAN HEPATOMA (HepG2) CELL LINE
Authors: Hamid Hazrulrizawati Abd , Yahaya Izzah Hayati
Published: October 2016

Objective: Clinacanthus nutans is one of the herbs that has been used in Asia as a traditional medicine for the treatment of serious diseases. The aim of this study is to investigate the phytochemical constituents (flavonoids and phenolics) and cytotoxicity against human hepatoma (HepG2) cancer cell lines of C. nutans extracts.

Methods: The fractions from C. nutans were extracted from hexane, methanol, chloroform and ethyl acetate by the solvent-solvent extraction method. The crude extracts (10 mg/ml) were tested against HepG2 cell lines using 3-(4, 5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. Phytochemical screening was done to determine the total phenolic content (TPC) and total flavonoid content (TFC).

Results: Methanol extract showed the strongest cytotoxic activity against HepG2 cell line with IC 50 of 43.9367μg/ml after 24 h of treatment compared to chloroform extract and ethyl acetate, 55.6112µg/ml and 62.0655µg/ml, respectively. Hexane extract formed the lowest cytotoxicity activity with IC50 of 68.3807µg/ml. Total phenolic content (TPC) was found to be highest in chloroform, which was 119.29 mg of gallic acid equivalent (GAE) and total flavonoid content (TFC), methanol was performed the highest value, which is 937.67 mg of butylated hydroxytoluene (BHT).

Conclusion: Different active compounds present in the extracts may contribute different cytotoxicity effects of crude extracts. The relationship data of total phenolic, total flavonoid, and cytotoxic potential of C. nutans, indicates that these plants might contain valuable active compounds as a chemotherapeutic agent. Further investigations to elucidate the chemical structures of active compounds are necessary for potential compounds discovery in drugs.
ANTIFUNGAL ACTIVITY OF PIMENTA DIOICA (L.) MERRIL AN AROMATIC MEDICINAL TREE
Authors: Bhat Akhilesh , A. Raveesha K.
Published: October 2016

Objective: To assess the antifungal activities of the extracts of leaves of Pimenta dioica against human pathogenic fungi and identify the class of phytochemical responsible for the biological activity.

Methods: The shade dried, and powdered leaves of Pimenta dioica were subjected to polarity based solvent extraction by soaking. The extracts were dried in a rotary flash evaporator and subjected to antifungal activity assay against Candida albicans, Microsporum canis and M. gypseum, by disc diffusion method. Antifungal active petroleum ether extract was subjected to phytochemical analysis to identify the active compound. The extract was then subjected to Thin Layer Chromatography (TLC) and Bioautography, by agar overlay method. The fractions were collected by Preparative TLC method and subjected to antifungal activity assay by disc diffusion method. Further, the Libermann-Burchard test was conducted to detect the broad group of compounds responsible for the bioactivity.

Results: Among the five extracts viz. petroleum ether, chloroform, ethyl acetate, methanol and aqueous, the petroleum ether extract showed significant antifungal activity against Microsporum canis (50 mm), Microsporum gypseum (60 mm) and Candida albicans (23 mm). Terpenoids, tannins and flavonoids were found to be the chief constituents of the petroleum ether extract. The TLC of the extract revealed 7 spots with the Rf values 0.37, 0.42, 0.45, 0.52, 0.59, 0.76, 0.96 with the solvent system of hexane and acetone (1:0.5). The bioautography assay revealed inhibitory activity in the spots at Rf values 0.52 and 0.59. These fractions obtained by preparative TLC also confirmed the same. The phytochemical analysis of the fractions on the TLC plate suggests that the compound is triterpene or steroid.

Conclusion: The antifungal activity of Pimenta dioica and the bioactive phytochemical has been reported in the present study. Preliminary phytochemical analysis has indicated that the compounds are triterpenes or steroids. The results indicate that the active compounds are potential lead molecules for new antifungal drugs in the management of infectious fungi.
A novel complex model of hemodialysis adequacy: Predictive value and relationship with malnutrition inflammation score
Authors: Vlatkovic Vlastimir , Trbojevic-Stankovic Jasna , Nesic Dejan , Stojimirovic Biljana
Published: October 2016

Target dialysis dose to ensure the best patient outcome is still a matter of
debate. Traditional models have a number of limitations and do not
comprehensively reflect all factors involved. In this study we present a new
complex model of dialysis adequacy, the hemodialysis adequacy score (HAS),
and evaluate its prognostic value, as well as its relationship with the
malnutrition-inflammation score (MIS). The components of HAS included
paradigms of the 6 major factors known to influence the outcome of
hemodialysis (HD) patients: the modified Karnofsky index (KI), the Charlson
comorbidity index (CCI), Kt/V and URR measures of dialysis dose, body mass
index (BMI) and serum albumin level, serum levels of hemoglobin and ferritin,
intact parathyroid hormone (iPTH) and calciumphosphorus solubility product.
The score was evaluated in a 24-month prospective study on 147 HD patients.
Odds ratio analysis showed that hospitalized patients had twice the chance to
have HAS >13 compared to those who were not hospitalized during the study
period (OR=2.152, CI 95% (1.0024- 4.619). Mortality rate was significantly
higher in patients with a HAS >13 at the 12-month follow-up (?2=16.416, p
<0.0001). Patients with a HAS?13 had significantly higher survival rate
(Kaplan- Meier), while those with a HAS>13 had significantly higher
probability of death (log-rank Cox- Mantel=17.920, df=1, p <0.00023). The HAS
directly and significantly correlated with the MIS at all measurements (p
<0.0001). Results confirmed that the HAS is a useful tool to assess dialysis
adequacy with a good prognostic value. The cutoff level for the HAS at 13
points was associated with an unfavorable outcome.
Electrochemical determination of resveratrol in dietary supplements at a boron-doped diamond electrode in the presence of hexadecyltrimethylammonium bromide using square-wave adsorptive stripping voltammetry
Authors: Yardim Yavuz
Published: October 2016

A sensitive electroanalytical methodology for the determination of resveratrol is presented for the first time using adsorptive stripping voltammetry at a bare boron-doped diamond (BDD) electrode. In cyclic voltammetry, resveratrol shows one irreversible and an adsorption-controlled oxidation peak at a BDD electrode. The voltammetric results indicated that in the presence of hexadecyl trimethyl ammonium bromide, the BDD electrode remarkably enhanced the oxidation of resveratrol, which leads to an improvement in the peak current with a shift of the peak potential to more positive values. Using the square-wave stripping mode, the compound yielded a well-defined voltammetric response in 0.1 M nitric acid solution containing 100 ?mol L-1 hexadecyl trimethyl ammonium bromide at 0.74 V (vs. Ag/AgCl), after 60 s accumulation at the open-circuit condition. A linear calibration graph was obtained in the concentration range 0.025 to 60.0 ?g mL-1, with a detection limit of 0.0063 ?g mL-1. The applicability of the proposed method was verified by analysis of resveratrol in commercial dietary supplements.
Blogging Slum Tourism: A Critical Discourse Analysis of Travel Blogs
Authors: Muldoon Meghan , Mair Heather
Published: October 2016

Modern slum tourism, rooted in the social justice movements of South Africa and Brazil in the early 1990s, has become an increasingly popular practice among tourists looking for experiences off the beaten path. Unsurprisingly, a form of tourism that allows wealthy travelers to experience
the "reality" of how poor people live has elicited criticism and controversy. Slum tourism has been lauded as an innovative economic opportunity for poor urban neighborhoods and has been condemned for promoting poverty voyeurism. The first author undertook a critical discourse analysis in
the winter of 2013–2014, analyzing slum tourism discourse in travel blogs. Eighteen travel blogs and 36 blogs postings were analyzed using a Foucauldian critical discourse perspective. The study found that travel bloggers use a number of structures of authority and structures of responsibility
to convince their readers of the value of this touristic practice and the integrity of the travelers who would choose to participate in slum tourism.
Superelectrophilic activation of 5-hydroxymethylfurfural and 2,5-diformylfuran: organic synthesis based on biomass-derived products
Authors: Ryabukhin Dmitry S , Zakusilo Dmitry N , Kompanets Mikhail O , A.Tarakanov Anton , Boyarskaya Irina A , Artamonova Tatiana O , Khohodorkovskiy Mikhail A , Opeida Iosyp O , Vasilyev Aleksander V
Published: October 2016

The reaction of 5-hydroxymethylfurfural (5-HMF) with arenes in superacidic trifluoromethanesulfonic acid (triflic acid, TfOH) as the solvent at room temperature for 1–24 h gives rise to 5-arylmethylfurfurals (yields of 17–91%) and 2-arylmethyl-5-(diarylmethyl)furans (yields of 10–37%). The formation of these two types of reaction products depends on the nucleophilicity of the arene. The same reactions under the action of acidic zeolites H-USY in high pressure tubes at 130 °C for 1 h result in the formation of only 5-arylmethylfurfurals (yields of 45–79%). 2,5-Diformylfuran (2,5-DFF) in the reaction with arenes under the action of AlBr3 at room temperature for 1 h leads to 5-(diarylmethyl)furfurals (yields of 51–90%). The reactive protonated species of 5-HMF and 2,5-DFF were characterized by NMR spectroscopy in TfOH and studied by DFT calculations. These reactions show possibilities of organic synthesis based on biomass-derived 5-HMF and 2,5-DFF.
PARTICLE ACCELERATION IN SOLAR FLARES AND ASSOCIATED CME SHOCKS
Authors: Petrosian Vahé
Published: October 2016

Observations relating the characteristics of electrons seen near Earth (solar energetic particles [SEPs]) and those producing flare radiation show that in certain (prompt) events the origin of both populations appears to be the flare site, which shows strong correlation between the number and spectral index of SEP and hard X-ray radiating electrons, but in others (delayed), which are associated with fast coronal mass ejections (CMEs), this relation is complex and SEPs tend to be harder. Prompt event spectral relation disagrees with that expected in thick or thin target models. We show that using a more accurate treatment of the transport of the accelerated electrons to the footpoints and to Earth can account for this discrepancy. Our results are consistent with those found by Chen & Petrosian for two flares using nonparametric inversion methods, according to which we have weak diffusion conditions, and trapping mediated by magnetic field convergence. The weaker correlations and harder spectra of delayed events can come about by reacceleration of electrons in the CME shock environment. We describe under what conditions such a hardening can be achieved. Using this (acceleration at the flare and reacceleration in the CME) scenario, we show that we can describe the similar dichotomy that exists between the so-called impulsive, highly enriched (3He and heavy ions), and softer SEP events and stronger, more gradual SEP events with near-normal ionic abundances and harder spectra. These methods can be used to distinguish the acceleration mechanisms and to constrain their characteristics.