bluuebunny/crossref_metadata_2025 huggingface dataset:
Bypassing Skepticism to Add Reserve: Cases of Successful Hydraulic Fracturing in Karim Formation
Authors: Al Kalbani M.. , Al Saadi H.. , Mirza M.. , Kurniadi S. D. , Hilal Ahmed , Al Kalbani M. S. , Kelkar S..
Published: October 2018

When oil prices are low, the oil industry tends to reduce its capital expenditure to fund new projects, such as exploration and development projects. The reduction in exploration activity ultimately affects the operators’ reserve balance. These conditions push each operator to use innovative solutions to increase reserves. Hydraulic fracturing is considered one of these solutions because it enables revisiting the possibility of producing an uneconomic reservoir with the existing wells. One reservoir that is being reevaluated is the Karim formation located in the Karim Small Fields (KSF), the Sultanate of Oman.

The Karim formation is divided into three segments, with the most promising being the Lower Khaleel, which was initially considered uneconomic to develop. The Khaleel is a sandstone formation at approximately 2000 m depth, with fair porosity and permeability and containing moderate-viscosity oil. The current recovery factor in the Khaleel is still less than 5%, and it is not considered for a full-field development plan due to low production results.

Because the wells drilled in the Khaleel formation were not prepared for a fracturing operation, several challenges appeared during early review, including the well trajectory and azimuth, completion condition, intervention strategy, data availability, and reservoir understanding on the formation water source and its connection to the Khaleel. The project was separated into three phases: feasibility and technical study phase, fracturing trials and evaluation phase, and fracturing understanding and optimization phase. Results are available for the first two phases, and a plan has been formulated for the third phase.

The feasibility and technical study involves understanding the geology, geomechanics, and petrophysics of the wells in which a fracturing operation was performed previously in a different formation. This study was followed by a candidate selection step involving more than 10 existing wells. The candidate selection process used a novel workflow to incorporate all the challenges into the selection criteria. Results of the candidate selection phase led to selection of the top three wells for fracturing operations in the Khaleel formation. Two out of three wells were selected for hydraulic fracturing treatment in the initial trial phase. Observations and results have been obtained from the execution of the trial hydraulic fracture jobs in these wells.
A Model for Acid Fracture Conductivity Based on Asperity Deformation with Coupled Normal-Shear Behavior of Rough Surfaces
Authors: Zhang Wenyu , Jin Xiao , Zhu Ding
Published: October 2018

Natural fractures are oftentimes not orientated in the direction of in-situ principal stresses. When developing naturally fractured reservoirs, the complex fracture network is affected by the shear stresses acting on the fracture surfaces. In some rare cases, the main fracture may not align with the principal stresses. Under such circumstances, shear stresses and displacements during fracture closure will impact the overall conductivity, especially for acid fracturing treatment, where flow paths are supported by the roughness of unevenly acid-etched fracture walls.

In this paper, we present a new approach to model acid fracture conductivity by allowing combined normal and shear loading on fracture walls. The closure of rough surfaces is modeled as elastic deformation of asperities. The model considers the mechanics of asperity contacts and statistical descriptions of interface roughness and asperity contact orientation for shear slippage between asperities. A numerical simulation algorithm is implemented to evaluate the fracture displacement under complex loading conditions. The overall conductivity is then obtained from numerical simulation based on deformed fracture apertures. The model was validated with the experimental observation under normal closure condition. A parametric study was carried out to evaluate the rock mechanical properties and fracture geometries on the conductivity behavior of acid fracturing.

Modeling results show that the interface closure behavior can be significantly affected by the asperity contact orientations. If slipping among asperities is considered, larger deformations during fracture closure are observed from simulation comparing to results from conventional fracture closure models based on summit-to-summit asperity contact. Sensitivity analysis indicates that the overall conductivity of a fracture depends on mechanical properties of the rock, distribution of asperity contact orientation, and shear loading conditions.

The new approach proposed in this paper provides access to acid fracture conductivity estimation under various in-situ stress conditions and fracture orientations. This model can be helpful in evaluating fracture treatment in reservoirs with natural fractures or complex subsurface structures.
Good Tests Cost Money, Bad Tests Cost More - A Critical Review of DFIT and Analysis Gone Wrong
Authors: Hawkes R. V. , Bachman R.. , Nicholson K.. , Cramer D. D. , Chipperfield S. T.
Published: October 2018

Analysis of mini-frac or, as commonly referred to in North America, Diagnostic Fracture Injection Tests (DFITs), have traditionally been the sub-discipline of completion & hydraulic fracture stimulation engineers. Conducting such tests has direct and indirect costs resulting from the test itself and the extended time required for the pressure falloff, that delays the completion of the well. The benefits must therefore outweigh the costs if the test is to be justified. The value is evident as these tests are performed regularly around the world as it is one of only a few processes that can help quantify within the same test both geomechanical properties and reservoir performance drivers.

The authors will present examples and lessons learned from regions around the world. In addition, the availability of a large quantity of public, high-quality data from oil & gas operators in Western Canada operating in shale and ultra-tight formations enable an assessment of the successes and failures of wellbore completions, reservoir types, and operator procedures. This treasure-trove of data will help completion engineers regardless of their basin of operations to overcome one of industries challenging questions "did the test achieve its objectives."
A Theoretical Model for GHG Emissions Due to Biochar Application in Tropical Agricultural Soils
Authors: Novais Sarah Vieira , Oliveira Zenero Mariana Delgado , Frade Elizio , Lima Renato , Pelegrino Cerri Carlos Eduardo
Published: October 2018

Core Ideas

Biochar mitigates greenhouse gas (GHG) emissions when applied to soils.

The reduction in biochar pH leads to higher GHG mitigation.

Enhancing biochar pyrolysis temperature also leads to higher GHG mitigation.

CO2 emission is explained negatively by the variables soil texture and biochar pH.

CO2 emission is explained positively by pyrolysis temperature and biochar dose.

Biochar, a pyrolysis product, has the potential to reduce greenhouse gas (GHG) emissions while increasing the soil water holding capacity. The purpose of this paper is to model biochars GHG emission based on its applied dose, its pH value, pyrolysis temperature and soil texture. Poultry manure and sugarcane straw biochar produced at two temperatures (350 and 650°C), were applied in three doses (12.5, 25, and 50 Mg ha−1), to sandy and clayey soils at two soil pH values (original 7.5 and adjusted to 5.5). The concentrations of CO2, CH4 and N2O were determined using gas chromatography. Increasing the biochar pyrolysis temperature and reducing the soil pH to 5.5 reduced the CO2, CH4, and N2O emissions from the soil. The mitigating effect of biochars was more evident in the sandy soil, since the clayey soil was highly buffed. The CO2 emission, explained negatively by the variables soil texture and biochar pH and positively by the variables pyrolysis temperature and biochar dose, had the final equation: CO2 = 82.28 – 0.05Cclay – 0.08pH + 6.98Tpyrolysis + 0.64Dbiochar (R2 = 0.65).
Cover Crops Reduce Nitrate Leaching in Agroecosystems:A Global Meta‐Analysis
Authors: Thapa Resham , Mirsky Steven B. , Tully Katherine L.
Published: October 2018

Cover crops are well recognized as a tool to reduce NO3− leaching from agroecosystems. However, their effectiveness varies from site to site and year to year depending on soil, cash and cover crop management, and climate. We conducted a meta‐analysis using 238 observations from 28 studies (i) to assess the overall effect of cover crops on NO3− leaching and subsequent crop yields, and (ii) to examine how soil, cash and cover crop management, and climate impact the effect of non‐leguminous cover crops on NO3− leaching. There is a clear indication that nonleguminous cover crops can substantially reduce NO3− leaching into freshwater systems, on average by 56%. Nonlegume–legume cover crop mixtures reduced NO3− leaching as effectively as nonlegumes, but significantly more than legumes. The lack of variance information in most published literature prevents greater insight into the degree to which cover crops can improve water quality. Among the factors investigated, we identified cover crop planting dates, shoot biomass, and precipitation relative to long‐term mean precipitation as potential drivers for the observed variability in nonleguminous cover crop effectiveness in reducing NO3− leaching. We found evidence indicating greater reduction in NO3− leaching with nonleguminous cover crops on coarse‐textured soils and during years of low precipitation (<90% of the long‐term normal). Earlier fall planting and greater nonleguminous shoot biomass further reduced NO3− leaching. Overall, this meta‐analysis confirms many prior studies showing that nonleguminous cover crops are an effective way to reduce NO3− leaching and should be integrated into cropping systems to improve water quality.

Core Ideas

Nonleguminous cover crops reduced NO3− leaching by 56% over no cover crop controls.

Nonlegume–legume mixtures reduced NO3− leaching equivalent to nonlegumes, but significantly more than legumes.

Cover crop planting date, shoot biomass, and precipitation affected nonlegume effects on NO3− leaching.

Nonlegumes reduced NO3− leaching more effectively on coarse‐textured soils and in drier years.

Earlier planting dates and greater shoot biomass enhanced NO3− leaching reductions with nonlegumes.
The Effect of Lithology and Agriculture at the Susquehanna Shale Hills Critical Zone Observatory
Authors: Li Li , DiBiase Roman A. , Del Vecchio Joanmarie , Marcon Virginia , Hoagland Beth , Xiao Dacheng , Wayman Callum , Tang Qicheng , He Yuting , Silverhart Perri , Szink Ismaiel , Forsythe Brandon , Williams Jennifer Z. , Shapich Dan , Mount Gregory J. , Kaye Jason , Guo Li , Lin Henry , Eissenstat David , Dere Ashlee , Brubaker Kristen , Kaye Margot , Davis Kenneth J. , Russo Tess , Brantley Susan L.
Published: October 2018

Core Ideas

Two new subcatchments are used to test the importance of lithology and land use.

Differences in lithology and land use result in differences in soils and waters.

Despite differences, all catchments have a shallow and a deep water table.

The relative importance of flow paths controls distinct chemistry response to discharge.

Cross‐site comparison will ultimately enable upscaling from the catchment to large scale.

The footprint of the Susquehanna Shale Hills Critical Zone Observatory was expanded in 2013 from the forested Shale Hills subcatchment (0.08 km2) to most of Shavers Creek watershed (163 km2) in an effort to understand the interactions among water, energy, gas, solute, and sediment. The main stem of Shavers Creek is now monitored, and instrumentation has been installed in two new subcatchments: Garner Run and Cole Farm. Garner Run is a pristine forested site underlain by sandstone, whereas Cole Farm is a cultivated site on calcareous shale. We describe preliminary data and insights about how the critical zone has evolved on sites of different lithology, vegetation, and land use. A notable conceptual model that has emerged is the “two water table” concept. Despite differences in critical zone architecture, we found evidence in each catchment of a shallow and a deep water table, with the former defined by shallow interflow and the latter defined by deeper groundwater flow through weathered and fractured bedrock. We show that the shallow and deep waters have distinct chemical signatures. The proportion of contribution from each water type to stream discharge plays a key role in determining how concentrations, including nutrients, vary as a function of stream discharge. This illustrates the benefits of the critical zone observatory approach: having common sites to grapple with cross‐disciplinary research questions, to integrate diverse datasets, and to support model development that ultimately enables the development of powerful conceptual and numerical frameworks for large‐scale hindcasting and forecasting capabilities.
Possibilities of using phospho-soda in patients with complicated colon preparation for endoscopy
Authors: Titaeva A. A. , Belousova E. A. , Tereshchenko S. G.
Published: October 2018

Endoscopic screening is the main method of colon examination. An important factor for the accurate diagnosis of various pathological changes in the mucous membrane of the lower part of the digestive tract is the degree of its visualization, which directly depends on the quality of preparation for colonoscopy. There are many colon cleansers, but the peristaltic motion of the gut slows down in various diseases and syndromes, which results in the reduced accuracy of endoscopy.

The paper presents the analysis of colon preparation quality using Phospho-soda (Casen Recordati, S.L., Spain) for colonoscopy in 198 patients with pathological conditions that impedes passage of all bowel contents: inflammatory bowel disease, acromegaly, and hypotonia of the large intestine. The authors carried out a comparative analysis with a control group, which included 106 patients without factors that slowed down the peristaltic motion of the intestine, who were preparing for endoscopic examination according to a similar scheme.

The study showed that using Phospho-soda to prepare for endoscopic examination in patients with decreased colonic tone resulted in the efficacy of the drug comparable with its efficacy in a group of patients without dysmotility.
Detoxification therapy for chronic gastrointestinal diseases
Authors: Balukova E. V.
Published: October 2018

Enterosorption, as one of the methods of detoxification therapy, has become widespread in clinical practice and is successfully used in the treatment of various diseases of the gastrointestinal tract (GI tract). Safety and ease of use, absence of contraindications and the possibility of combination with other medicines allow individualizing therapeutic tactics, avoiding the side effects of therapy and achieving high treatment effectiveness while reducing its duration.
Planejamento Setorial e Regional: um modelo de integração entre ferramentas de previsão aplicado ao transporte rodoviário de cargas
Authors: Blois Henrique Dias , Finamore Eduardo Belisario Monteiro de Castro
Published: October 2018

Esta pesquisa visa analisar o setor de transporte por meio de um modelo que integra Cenários Prospectivos a Dinâmicas de Sistemas visando prever alternativas futuras para o transporte rodoviário de cargas na Região do COREDE Produção do Rio Grande do Sul/Brasil. Na primeira ferramenta de pesquisa foi adotado o método descrito por Grumbach (2012), no qual peritos contribuem para a construção dos cenários. Após a geração dos cenários, foi realizada a integração com a modelagem hard da Dinâmica de Sistemas que busca disponibilizar alternativas que possibilitem análise, descrição e simulação de tendências para os próximos cinco anos.  Os resultados mostram um conjunto de cenários e ações ao apontar oportunidades e ameaças do ambiente externo, pontos fortes e fracos do ambiente interno, fundamentando decisões estratégicas e operacionais no presente. Também realiza previsões para o setor através de simulação, bem como discute a possibilidade da implementação de uma agência de desenvolvimento regional, como um agente facilitador do modelo proposto.  O modelo de integração proposto nesse estudo mostrou-se útil porque reduziu o número de incertezas futuras, construídas pela redução de eventos com maior probabilidade de ocorrência. Essa característica é importante pois focaliza o investidor naqueles eventos que podem de fato interferir na evolução do sistema analisado.
Tecnificação de Produtores e Estruturas de Governança no Sistema Agroindustrial de Leite
Authors: Acosta Daniela Caldas , Souza José Paulo de , Bankuti Sandra Mara Schiavi
Published: October 2018

As evoluções observadas na trajetória do Sistema Agroindustrial (SAG) do leite no Brasil refletiram no modo de operação e nas relações dos segmentos produtor e processador. Embora esse SAG apresente crescimento, a diversidade no nível tecnológico do segmento de produção rural tem efeito sobre o desempenho da cadeia de forma geral, e se estende para a estrutura das relações, impactando na distribuição de valor nas transações. Assim, toma-se como base a proposta de entender a estratégias de organização dos segmentos que integram a cadeia produtiva por intermédio da Economia dos Custos de Transação e Teoria dos Custos de Mensuração, de forma pontual no estado do Paraná. Para isso, o seguinte objetivo foi definido: compreender como se dão as relações entre o segmento produtor e processador no SAG de leite, ao se considerar o nível de especialização tecnológica dos produtores nas diferentes regiões do estado do Paraná. Para isso, utilizou-se procedimentos metodológicos sustentados em pressupostos qualitativos, e pesquisa descritiva. Os dados primários foram obtidos a partir de entrevistas semiestruturadas com produtores e processadores localizados nas diferentes regiões do Estado. Como resultado identificou-se que as estruturas de governança predominantes  são de forma híbrida, envolvendo contratos formais e, em sua maioria, informais, requerendo confiança e reputação. A contratação formal se associa a níveis elevados de tecnificação no segmento de produção rural, sendo encontrada apenas na região Centro-Oriental do Estado, indicando que a elevação na capacidade produtiva tem influência na definição dos arranjos, e consequente obtenção de eficiência e melhor distribuição de valor.
Aplicação do Método Mesmis para Análise da Sustentabilidade de Sistemas de Produção da Pecuária Familiar em Área do Bioma Pampa no Rio Grande do Sul
Authors: Nicoloso Carolina Da silveira , Silveira Vicente Celestino Pires , Coelho Filho Roblein Cristal , Quadros Fernando Luiz Ferreira de
Published: October 2018

Por representar um conjunto de ecossistemas muito antigos, o Bioma Pampa apresenta flora e fauna próprias e grande biodiversidade, ainda não completamente descrita pela ciência. Desde a colonização ibérica, a pecuária extensiva (bovinos de corte e ovinos) sobre os campos nativos tem sido a principal atividade econômica da região. A progressiva introdução e expansão das monoculturas e das pastagens com espécies exóticas têm levado a uma rápida degradação e descaracterização das paisagens naturais do Pampa. O objetivo deste artigo é avaliar a sustentabilidade de diferentes sistemas de produção da pecuária familiar no Rio Grande do Sul. Foi utilizado o método MESMIS para a analise de sustentabilidade de três grupos de sistemas de produção identificados: Campo Nativo (CN), Campo Nativo e Cultivos (CN+C) e Campo Nativo e Soja (CN+S). Foi identificada diferença significativa (p<0,05) para o atributo “Produtividade” entre os sistemas CN+C e CN+S, sendo o primeiro superior ao segundo. Para os demais atributos de sustentabilidade não houve diferenças significativas entre os sistemas de produção da pecuária familiar estudados.
O Comportamento de Consumidores Diante da Prática do Greenwashing
Authors: Fialho Letícia Sousa , Marquesan Fábio Freitas Schiling
Published: October 2018

Os consumidores mesmo assumindo um papel primordial e impulsionador ao exigir das empresas ações que sigam normas de preservação ambiental, têm dificuldade de identificar aquelas tidas como verdadeiramente sustentáveis e essa confusão incentiva o greenwashing. Diante disso, o Conselho Nacional de Autorregulamentação Publicitária – CONAR, órgão responsável em receber, avaliar e julgar possíveis denúncias de greenwashing tem buscado impedir que os consumidores sejam ludibriados com falsas mensagens ambientais. Nesse quadro, este artigo objetiva averiguar o comportamento dos consumidores frente à prática greenwashing. A pesquisa possui caráter qualitativo e utilizou como fonte de dados tanto o sítio do CONAR por meio de uma pesquisa documental, quanto à aplicação de questionário com o apoio do software de desenvolvimento de pesquisa Survey Monkey. Os resultados demonstraram que mesmo os consumidores sendo céticos em relação à publicidade verde, eles não tem o conhecimento adequado sobre o significado do greenwashing, não buscam verificar a veracidade das informações anunciadas e estão divididos entre denunciar ou não um caso de greenwashing, justificando especialmente não ter conhecimento do CONAR. Conclui-se que a consciência do consumidor está mudando gradativamente, mas ainda assim é necessário um comportamento mais crítico em se tratando do greenwashing a fim desta prática ser diminuída.
A Legislação e a Nova Agenda Urbana: aporte para a gestão das cidades e de atividades econômicas urbanas
Authors: Bernardy Rógis Juarez , Silveira Rogério Leandro Lima da
Published: October 2018

Diversos fatores influenciam na dinamicidade de uma cidade, tais como as características demográficas, a diversidade de atividades econômicas e a espacialização dos setores produtivos no ambiente urbano, a formação urbana horizontal unifamiliar e vertical mista e as condições da legislação municipal, que regulamenta e induz o uso do solo urbano. A legislação relacionada ao planejamento é particularmente interessante, pois, por um lado, possui menor capacidade de influenciar em áreas urbanas centrais, com usos mais consolidados, por outro, apresenta expressiva potencialidade para induzir o desenvolvimento em áreas urbanas orgânicas, em constante transformação, chamadas de policêntricas e não centrais. Esta pesquisa visa analisar a funcionalidade urbana vinculada à produção econômica por comércio, indústria e serviço, a partir de estudo das determinações legais contidas nos Planos Diretores de três cidades médias, localizadas no sul do Brasil: Passo Fundo (RS), Chapecó (SC) e Cascavel (PR). Enquadra-se como uma pesquisa qualitativa com base em fontes de legislações de Planos Diretores municipais, quanto à produção do uso do solo por atividades econômicas e sua conformidade com o Estatuto da Cidade (2001). Como resultados se observou que as legislações são flexíveis, indutoras do desenvolvimento urbano, pois permitem o uso do solo multifuncional, híbrido ou miscigenado, portanto, não são regulamentadoras, embora pouco vincule os instrumentos do Estatuto da Cidade (2001) para a produção do uso do solo para atividades econômicas, particularidade que poderia auxiliar na organização urbana e em orientações de investimentos econômicos futuros nestas cidades.
Agenda Governamental: influências na sua construção nos municípios integrantes da 31ª Secretaria de Desenvolvimento Regional de Itapiranga – SC
Authors: Söthe Ari , Junior Oklinger Mantovaneli , Kegel Patricia Luiza
Published: October 2018

A construção das agendas governamentais com a participação dos diversos atores precede o planejamento das políticas públicas. Diante disso, o presente artigo busca descrever a influência dos diversos eventos, atores e questões na construção das agendas dos municípios integrantes de abrangência da 31 Secretaria de Desenvolvimento Regional (SDR) de Itapiranga - SC. Inicialmente por meio da fundamentação teórica foram abordados os principais conceitos sobre políticas públicas e agenda governamental e seus diversos atores. Posteriormente foi realizada uma pesquisa descritiva e exploratória, de abordagem qualitativa, de levantamento por meio de entrevistas junto aos municipios pesquisados. A descrição dos dados evidencia que os entrevistados visualizam as agendas governamentais, como mecanismo fundamental na definição das ideias que devem prevalecer e integrar os planos governamentais. Denota-se que, a mídia tem influência sobre os diversos atores que participam do planejamento e implementação das agendas. Infere-se que a agenda pública é influenciada pelas demandas imediatas e setoriais. Por outro lado, a agenda de políticas públicas governamentais é influenciada por diversos eventos como, frustrações de receitas, judicialização de políticas, agenda eleitoral, entre outros. O fluxo das questões na construção da agenda governamental tem uma pequena competição, seu sucesso ocorre em função da força dos atores e disponibilidade de recursos. As questões são influenciadas pela sua compreensão como problema e suas possíveis soluções, assim como, em alguns casos pelas barganhas políticas. Conclui-se que, diversos atores como a mídia, políticos, lideranças, judiciário, conselhos e os próprios agentes do governo são influentes no processo de construção das agendas.
Immersion in Water During Active Labor Decreases Postpartum Hematocrit Fall Following Vaginal Delivery
Authors: Buyuk Gul Nihal , Kahyaoglu Serkan , Turgut Ezgi , Yumuşak Omer Hamid , Kose Caner , Ustun Yaprak
Published: October 2018

OBJECTIVE: The objective of the study was to investigate the effect of immersion in water strategy during labor on postpartum bleeding by calculating the postpartum reduction rates of the hematocrit values of the patients.STUDY DESIGN: The study groups consisted of 84 women undergoing vaginal delivery with immersion in water during labor (group 1) and the control group (group 2) of 84 women undergoing normal vaginal delivery. Patients who have received additional medical and surgical interventions for alleviation of postpartum hemorrhage, patients who have undergone an episiotomy and/or perineal trauma were not included in the study. All data were taken from patients who have delivered with spontaneous vaginal delivery. Postpartum hematocrit fall rates of the groups have been compared and the effect of immersion in water on postpartum hemorrhage has been evaluated.RESULTS: The study groups consisted of 84 women undergoing vaginal delivery with immersion in water during labor (Group 1) and the control group (Group 2) of 84 women undergoing vaginal delivery at the hospital. The women in the two groups were matched with respect to age, parity, birth weight and gestational age. The mean age of the women was 29.8±4.8 and 30.5±4.9 respectively. The mean hematocrit difference in the first group was 2.08 ± 1.88 and in the second group was 3.81 ± 1.55. The mean percentage of hematocrit reduction in the first group was 5.71% and in the second group 10.23%.CONCLUSION: Our data showed that mean hematocrit level decreases among women following vaginal delivery more than women who give birth vaginally within immersion in water during labor. The percentage of hematocrit reduction in the water birth group was lower than in the control group. Water birth seems to facilitate uterine contractions more efficiently following vaginal delivery.
Development of an Information System of Structures and Force Field Parameters of Chemical Compounds from Sri Lankan Flora
Authors: Rathnayake Samith , Weerasinghe Samantha
Published: October 2018

Background:

Sri Lanka offers a huge diversity of flora with a large proportion of those
being endemic to the island. Both the endemic and native plants species serve as a rich bank of
phytochemicals.

Method:

In this study, “Sri Lankan Flora” an online web-based information system of phytochemical
compounds isolated from the flora of Sri Lanka was proposed.

Results:

The database contained 3D structures of those compounds, calculated quantitativestructure-
activity relationship (QSAR) data and the GROMOS 54a7 force field parameters for each
and every compound. The manually curated chemical structures, activities and force field parameters
provide a possible direct avenue for computer-aided drug discovery. The present study is a
continuing project with a wider goal of building up a database, not only for assisting the computeraided
drug designing process, but also for other chemical applications, as the database includes
structural, physical, chemical and dynamic properties of chemical compounds of the flora of Sri
Lanka. The database is freely accessible at http://science.cmb.ac.lk/tools/slflora.
Aripiprazole: An FDA Approved Bioactive Compound to Treat Schizophrenia- A Mini Review
Authors: Kumar Arvind , Singh Harpreet , Mishra Amrita , Mishra Arun K.
Published: October 2018

Objective:

Aripiprazole, a synthetic compound, obtained by chemical modification of the
structure of quinolinone is considered as an atypical antipsychotic drug. The present review is an attempt
to summarize the updated information related to reported chemistry and pharmacology of Aripiprazole.

Development:

Aripiprazole, under development by Otsuka Pharmaceutical, was approved by the U.S.
Food and Drug Administration (USFDA) by the end of 2002 with an aim to treat patients with schizophrenia.
This drug got approved by European Commission in February 2013 to treat the patients having
severe manic episodes in bipolar I disorder Additionally, it got approval in Japan in January 2006 and in
Canada in 2014.

Pharmacology:

Aripiprazole shows high specificity for dopamine receptor especially D2 and D3, serotonin
5-HT1A and serotonin 5-HT2A receptors, reasonable specificity for dopamine D4, serotonin 5-
HT2C and 5-HT7, alpha1-adrenergic and histamine H1 receptors. It also shows moderate specificity for
the serotonin reuptake. The major side effects include headache, agitation, akithesia, anxiety, tachycardia,
insomnia, postural hypotension, constipation, vomiting, dizziness, nervousness and somnolence.

Conclusion:

The present article embarks the available information on Aripiprazole with emphasis on its
clinical pharmacology, mechanism of action, pharmacokinetics, pharmacodynamics, metabolism and
clinical trials.
Mechanistic Insights into Protonated Diamines-catalyzed Decarboxylation of Oxaloacetate
Authors: Fan Chuangang , Song Mingzhi
Published: October 2018

The chemical mechanisms of protonated diamines-catalyzed decarboxylation of oxaloacetic
acid anions in water solutions have been studied by using density functional theory. The calculated results
show that the activated Gibbs free energy of the decarboxylation step is the highest in the whole
diamine-catalytic processes for OA2-, and protonated ethylenediamine (ENH+) is the best catalyst of
the five diamines, which is consistent with the study of Thalji et al. However, for OA-, different with
OA2-, the dehydration step is the rate-determining one except 1,3-diaminopropane, and protonated 1,4-
diaminobutane is the best catalyst of the five catalysts. The results also indicate that the second amino
group participates in the reaction as the proton acceptor or proton donor, and it assists in decarboxylation
by hydrogen bonds, decreasing the active Gibbs free energy barrier of the whole catalytic process.
These results provide insight into the precise catalytic mechanism of several enzymes whose reactions
are known to proceed via an imine intermediate.
Anticancer and Antiviral Diketopiperazine Produced by the Red Sea Endophytic Fungus Penicillium chrysogenum
Authors: Hawas Usama W. , Abou El-Kassem Lamia T.
Published: October 2018

Scale-up fermentation of the endophytic fungus Penicillium chrysogenum in biomaltpeptone
media followed by cytotoxicity-guided fractionation led to the isolation of haenamindole, an
unusual diketopiperazine (DKP) alkaloid, along with other five known DKPs. Haenamindole was elucidated
on the basis of comprehensive 1D and 2D NMR spectroscopic including 15N-HSQC and 15NHMBC
and mass spectrometric analyses. The compound possesses the secondary hydroxamic acid
functionality of N-piperazindione ring system confirmed by methylation in sodium dimethyl sulfate
and dry dimethylformamide to yield haenamindole-22-N-methyl ether. However, haenamindole
demonstrated weak HCV protease activity with an IC50 value of 76.3µM, its cytotoxicity profiling in a
panel of up to 12 cell lines indicated significant cytotoxicity of the compound with pronounced selectivity
for colon-38 cancer cells compared to the human normal cells.
Synthesis and Biological Evaluation of PF-543 Derivative
Authors: Kim Seon Woong , Lee Taeho , Lee Joo-Youn , Kim Sanghee , Jun Hee-Sook , Park Eun-Young , Baek Dong Jae
Published: October 2018

PF-543 has been known as a substance that strongly inhibits SK1. However, it also exhibits antineoplastic activity that is lower than other inhibitors of SK1. In this study, we compared PF-543 and synthesized a newly designed derivative of PF-543 (compound 2) in which two aromatic structures were connected in para-form. The synthesized derivative showed inhibitory effect on SK1, similar to that of PF-543. However, it was more cytotoxic to HT29, AGS, and PC3 cells than PF-543. We also carried out a docking study for SK1 and demonstrated that the synthesized derivative showed interaction with SK1 similar to PF-543. Results obtained from this study suggest that the structure of compound 2 may be well substituted for the structure of PF-543 in terms of biological activity, providing us important structural information for the design of new derivatives of PF-543.
Chemical Profiles and Bio-Activities of Different Extracts of Terfezia Species and their Other Associated Fungi
Authors: Ghareeb Mosad A. , Khalaf Omar M. , Abdel-Aziz Mohamed S. , Saad Amal M. , Madkour Hassan M.F. , El-Ziaty Ahmed K. , Refahy Laila A.
Published: October 2018

Background:

Desert truffles (Terfezia species) are known by their vital nutritional benefits as they are considered as rich sources of vitamins, fatty acid, minerals and proteins.

Methods:

The chemical constituents of the different solvent extracts of Terfezia species were isolated and identified by column chromatography, spectroscopic and GC-MS analyses. Also, the ethyl acetate and acetone extracts of different fungal isolates, associated Terfezia, after grown on rice medium were screened for their antimicrobial, anticancer and antioxidant activities via disc agar plate, micro culture tetrazolium (MTT) and 2,2-azino-di-[3-ethylbenzo-thiazolin-sulphonate] (ABTS) assays, respectively. The promising fugal strains were molecularly identified by 18SrRNA tool.

Results:

Bio-guided separation of methylene chloride, ethyl acetate and n-butanol fractions of Terfezia species led to identification of nine compounds namely; (R)-4,8-dihydroxy-7-hydroxymethyl-6- methoxy isochroman-1-one (1), 4-deoxy-4α-phorbal-12-(2,3-dimethyl)butyrate-13-isobutyrate (2), oxyphylline B (3), terfezien A (4), latilagascene D (5), amaiouine (6), senbusine acetate (7), terfezien B (8) and marinoquinoline D (9). Moreover, sixteen compounds were identified in the n-hexane extract via GC-MS analysis, accounting for 93.69% of the total detected components in the extract. While, twenty five components were detected in the methylene chloride extract, representing 43.86% from total detected components in the extract. Eight fungal strains were isolated from Terfezia sp., powder by serial dilution methods and these fungi were cultivated on solid rice medium. Also, their ethyl acetate and acetone extracts were subjected to biological studies including antimicrobial, antioxidant and anticancer activities. The three potent fungal strains (1M, 4M and 8M) were identified by the molecular technique 18SrRNA as Aspergillus niger 1M-EGY-IQ, Penicillium crustosum 4M-EGY-IQ, and Fusarium proliferatum 8M-EGY-IQ for 1M, 4M and 8M, respectively.

Conclusion:

Terfezia sp., comprise a rich source of bioactive compounds and could be considered as an interesting candidate for the treatment of infectious diseases.
In Silico Identification of Novel Apolipoprotein E4 Inhibitor for Alzheimer’s Disease Therapy
Authors: Bano Saddia , Rasheed Muhammad Asif , Jamil Farrukh , Ibrahim Muhammad , Kanwal Sumaira
Published: October 2018

Introduction: Apolipoprotein E4 (ApoE) is a major genetic factor for developing Alzheimer’s disease (AD). It plays a vital role in brain to maintain a constant supply of neuronal lipids for rapid and dynamic membrane synthesis. Aggregation of beta amyloid plaques (Aβ) and neurofibrillary tangles in brain are responsible for onset of AD. The current study is designed to predict a drug against over activity of apoE4. 22 natural compounds (marine, microorganism and plant derivative) were used in current study.  Methods: These compounds were used as inhibitors to target apoE4 protein activity. Moreover, six synthetic compounds were docked with target protein to compare and analyze the docking results with natural compounds. S-Allyl-L-Cysteine, Epicatechin Gallate and Fulvic acid showed highest binding affinity (-7.1, - 7 and -7 kcal /mol respectively). Analysis of the docked complex showed that Epicatechin Gallate bonded with Gln156 and Asp35. Furthermore, Fulvic Acid showed hydrogen bonding with Glu27. Among synthetic compound, Tideglusib had highest binding affinity with target protein but did not show hydrogen bonding with any amino acid residue. Moreover, a natural compound S-Allyl-LCysteine also showed highest binding affinity but did not show hydrogen bonding with any amino acid residue.  Results and Conclusion: Our study highlighted Epicatechin Gallate as a potential lead compound on the basis of binding affinity and hydrogen bonding to inhibit the progression of AD.
Stability-indicating UPLC-PDA Method for Ambrisentan Tablets and Identification of a Main Degradation Product by UPLC-MS/MS
Authors: Ortigara Rodolfo , Steppe Martin , Garcia Cássia Virginia
Published: October 2018

Background:

Ambrisentan is a drug used to treat the pulmonary arterial hypertension symptoms,
commercialized as coated tablets. Drug quality control is an essential part for the development
and release of drugs for consumption; however, there are few studies related to the proposition of analytical
methods and stability study for ambrisentan.

Objective:

The development of an UPLC assay of ambrisentan in tablets with degradation product`s
elucidation was proposed.

Methods:

Tests with different solvents and chromatographic columns were carried out, achieving an optimal
condition using mobile phase in gradient mode, Waters® BEH C18 column and detection at 260 nm.

Results:

Satisfactory system suitability was obtained (theoretical plates, sensitivity and resolution
among peaks), with a reduced analysis time (6 minutes). The method was validated in accordance with
the international guidelines and it demonstrated adequate specificity, either for the drug assay as for the
identification and quantification of degradation product. It showed linearity (r= 0.999), accuracy (degradation
products recovery: 98.47 - 102.44; assay recovery: 99.98 - 104.32%) and precision (RSD:
0.69), with limits of quantification and detection in suitable magnitude in order to evaluate possible
drug degradation.

Conclusion:

UPLC method demonstrated to be fast with satisfactory robustness. The main ambrisentan
degradation product formed under thermal stress conditions was elucidated by UPLC-MS/MS and its
structure was suggested.
A Rapid and Sensitive Method for the Pharmacokinetic Study of Janumet (Sitagliptin and Metformin) Tablets by LC-MS/MS Coupled with Ion-Pair Solid Phase Extraction
Authors: Han Xiaonian , Wang Jing , Huang Jing , Peng Lirong
Published: October 2018

Background:

As first-line treatments for diabetes, sitagliptin and metformin have been
widely prescribed as a combination to enhance the therapeutic effect.

Objective:

To establish a methodology to simultaneously monitor the two drugs in vivo by a reversedphase
Liquid Chromatography-Tandem Mass Spectrometric (LC-MS/MS) method.

Methods:

The two drugs were extracted from 50 μl human plasma by ion-pair solid phase extraction.
The separation of the plasma samples was implemented on an Agilent Zorbax SB-CN column (150×4.6
mm, 5.0 µm). The mobile phase was the mixture (80:20, v/v) of methanol and 5.0 mM ammonium formate
in water (pH 4.5). An ion trap spectrometer equipped with an electrospray ionization source was
utilized to detect the elution in positive mode. Quantification of the analytes was achieved by Multiple
Reaction Monitoring (MRM) using the transitions of m/z 408.3→235.1 for sitagliptin and m/z 130.1→
60.2 for metformin.

Results:

Sitagliptin and metformin demonstrated good linearity among the range of 1.00-1000 ng/mL
and 5.00-4000 ng/mL. The intra-day and inter-day investigations displayed precisions of ≤ 3.6% and an
accuracy range of -7.5% to 6.0% for the two drugs. The mean recovery of the two drugs was 96.0% and
98.5%. Under mandatory storage conditions, both the drugs gave an acceptable stability. The throughput
of the assay was found to be more than 100 plasma samples per day ascribed to the run time of 3.0
min for each sample.

Conclusion:

The developed method was successfully applied to a pharmacokinetic study for a fixeddose
tablet formulation containing 50 mg sitagliptin and 500 mg metformin in 12 healthy volunteers.
Compatibility Determination of Drug-Polymer, Drug-Excipient & Drug-Intravenous Admixtures Using Chemometric-assisted UVspectrophotometry
Authors: Mohamed Amir Ibrahim , El-Khamery Amal Abd-Elaal , Herry Mohamed Ismail , Mohamed Alaa Ibrahim
Published: October 2018

Purpose:

A new multivariate chemometric approach was developed for fast and economic
compatibility determinations of ranitidine hydrochloride (as model drug) with certain pharmaceutical;
polymers (Alginate & Chitosan), excipient (Lactose) and intravenous fluids (Dextrose, Ringer & Dextrose/
Ringer). Binary mixtures of the drug and each item were prepared and investigated by chemometric-
assisted UV- spectrophotometry as well as by HPLC reference method.

Methods:

Five drug concentration levels (0.004-0.025mg/ml) of test-mixtures were used and the average
drug recovery percent after two and seven days of storage from initial concentration was determined.
Physico-chemical techniques including DSC, XRD, & FTIR were also performed to investigate
the nature of the observed drug-additive interactions.

Results:

UV-chemometric and HPLC results showed that ranitidine stability in mixture aqueous solutions
appears to be concentration dependent. The ranitidine content remained greater than 90% in alginate
& chitosan test mixtures at all used drug concentrations (0.004-0.025mg/ml), while in lactose, dextrose,
ringer & dextrose/ringer test mixtures fell below 90% at low drug concentrations (0.004-
0.009mg/ml), which suggests more ranitidine compatibility with alginate & chitosan rather than the
other additives.

Conclusion:

The developed chemometric method, employing UV absorbance data successfully used as
simple, rapid, and economic alternative tool in drug-additive compatibility determinations.
A Review on the Study of Temperature Effects in the Design of A/D Circuits based on CNTFET
Authors: Marani Roberto , Perri Anna Gina
Published: October 2018

In this paper, we review a procedure to study the effects of temperature in the design of
A/D circuits based on CNTFETs. At first, we briefly describe a compact model, already proposed by
us, in which the temperature variation in the drain current equation and in energy band gap is considered.
Then, the effects of temperature variations in the design of analog circuits, such as a cascode
current sink mirror and an Operational Transconductance Amplifier (OTA), and in the design of
digital circuits including in particular NAND and NOR logic gates, are illustrated and widely discussed.
Purification of Cinnamic Acid and Aporphine Alkaloids from Enicosanthellum pulchrum Twig Extract and their Biological Activities
Authors: Nordin Noraziah , Mohd Yazid Noor Shafifiyaz , Zajmi Asdren , Elias Marjanu Hikmah
Published: October 2018

Background:

Various methods of isolating compounds from plants have been described
previously, which include conventional or modern techniques. A preparative-HPLC (prep-HPLC)
system has become one of the most convenient methods, with high purity compound as well as consumes
less purification time.

Objective:

This study is intended to purify compounds from E. pulchrum twig extract using prep-
HPLC technique and to test all compounds in several biological activities.

Methods:

Prior to purification using prep-HPLC, the twig extract was injected onto HPLC to develop
the method through its chromatograms. The established method from HPLC was used to separate
the constituents using prep-HPLC. Purified compounds were elucidated through NMR and MS
methods as well as through comparison with previously reported data. Three different biological activities
were then conducted on the compounds, including cytotoxicity, DPPH, FRAP, and disc diffusion
assays.

Results:

Cinnamic acid (1) and two aporphine alkaloids (liridine (2) and lysicamine (3)) have been
successfully purified and identified. These compounds were first isolated from Enicosanthellum
pulchrum using prep-HPLC. Cytotoxic activity revealed that liridine (2) showed strong inhibition
against WEHI-3B leukaemic cells of 8.7 µM after 24 h of treatment. In contrast, cinnamic acid (1)
and lysicamine (3) exhibited strong inhibitions in antibacterial activity against Staphylococcus
aureus, S. epidermidis, Bacillus cereus, Pasteurella multocida and B. subtilis with more than 15 mm
of inhibition zone.

Conclusion:

These phytochemical findings exhibit three isolated compounds from twig extract of E.
pulchrum with diverse biological potential to be developed as new agents.
Speed of Things (SoT): Evolution of Isolation-to-Intermingle (I2I) Technology Transition Towards IoT
Authors: Ravishanker  , Luhach Ashish K. , Kumar Sykam V.N. , Poonia Ramesh C.
Published: October 2018

Background:

In today’s world it is highly difficult to manage the smart things and fulfill
the communication needs without the Internet as it provides ultimate means for human to human
(H2H) communication. The ‘things’ could be entities or devices that contribute for the communication.
But to enhance and improve such smart communication among the things that involves nonhuman
intervention, there is a need to add few more smart capabilities to the Internet. As the world
of Internet is on its way of transformation into a new smart world called ‘Internet of Things’ (IoT)
where the things should possess the ability of sensing, communication and control to let the things
exchange information without complete intervention of humans to provide advanced and qualitative
services, which is possible with the help of protocols.

Objective:

This paper discusses how the transition could be started and being progressed in wired
and wireless systems, and how it changes the traditional means of communication among different
devices and humans into a smart way.

Methods:

Transition here refers to how isolated things are being intermingled with each other to
generate a smart protocol communication.

Results and Conclusion:

The aim of such transition is to improve the efficiency, flexibility, adaptability
and interoperability. This paper also explores various factors that contribute to IoT.