bluuebunny/crossref_metadata_2025 huggingface dataset:
Korchagina P–108: Breaking ERD Records Offshore North Caspian Sea: A Case Study
Authors: Zvyagin Vasily , Dubovik Alexander , Rizvanov Rail , Huseynov Mammad , Sissenov Olzhas , Baskakov Sergey
Published: November 2016

LUKOIL's drilling operations on Korchagina field offshore Caspian, involving 16 extended reach wells were recently culminated by completing the longest well on the project. Well P-108 was planned to the total depth of 9000 mMD and required precise engineering and special techniques especially with respect to lower completion installation. This paper provides a case history of the challenging lower completions deployment along with the well design summaries and operational parameters that led to successful execution.

Based on the previous experience, installation of the lower completions on the long reach wells requires rotation. With a standard lower completions design incorporating sections of 6⅝-in and 5½-in stand alone screens, the torsional loads were exceeding torque limitations of the completions and running strings. The approach used for this well was based on the best design and operational practices from the previously drilled extended reach wells and comprising of selection of optimal screen sizes, running string optimization, friction factor reduction, hole condition management, cooperation with geomechanics and well placement teams throughout the course of drilling the section was planned on this well for successful execution.

The well was successfully drilled and completed at a shallower total depth than planned - 8005 mMD, due to geological reasons. Nevertheless, this well broke several records on the project: the longest well, the longest completions string – 5032 m, the highest daily footage in 9½-in section – 837 m. It also broke one of the world records: the longest 9½-in one bit run – 4895 m. During well planning and execution stage, key elements of well design and implementation were subjected to intense analysis through systematic optimization processes. Along with management of well construction parameters and practices, this resulted in technical integration of multiple discipline, such as well engineering, completions engineering, geomechanics, mud engineering, well placement, directional drilling. Understanding the key challenges of the well and collaborative work between an operator and service providers in addressing the issues, allowed to achieve exceptional results in drilling and completing the longest well on the project without HSE or environmental impact.

Successful execution of the well has established new benchmarks on the projects and on the Northern Caspian and pushed the limits of extended reach drilling (ERD) wells on Korchagina to world class ERD wells. Design considerations and applied techniques provided in this case history can be used for the future ERD wells with non-trivial conditions with regards to the lower completions installation.
Quasi-3D (Q3D) Hydraulic Fracture Model: An Enhanced Workflow to Model Height Growth in Asymmetric Multilayer Formations
Authors: Tayyab Imran
Published: November 2016

Pseudo-3D (P3D) fracture models have been extensively researched. However most of these models are either very simple or too complex. This study proposes a workflow, based on equilibrium height concept (EHC) and layered reservoir data, to calculate fracture height along length axis and optimally size frac treatments.

The main calculation is based on Linear Elastic Fracture Mechanics. It estimates the fracture height by equating stress intensity factor at tip & bottom of frac to fracture toughness of that layer. The original model was designed for a 3-layer system, which inadequately captured formation heterogeneity especially when fracking interbedded reservoirs. To overcome the limitation, this workflow extrapolates the EHC using reservoir layer table where rock properties are defined with respect to depth. Initially a fracture height is assumed to calculate treatment pressure, which is then compared with pressure from 2D models. If the difference is greater than error limit, higher height is assumed to rerun the model. For each height, fracture top & bottom depths are calculated using frac geometric description. These depths are correlated with reservoir table to obtain rock parameters for those layers. This algorithm is run iteratively until a solution is achieved within error limit. As rock parameters are correlated for each run, any layer above and below the target zone can act as bounding layer therefore no grouping of layers is required. Further, the frac is divided in number of units along the length axis and optimum width & net pressure is calculated for each unit to estimate its height. Final output is a schematic of fracture height all along the length axis that is calculated from reservoir description. Number of units in which frac is divided along length axis to calculate height should be a compromise between resolution and computational time. As height is calculated from P3D module for all units, this is analogous to 3D models that work on mesh-grids, hence workflow is named Quasi-3D (Q3D) model. Finally, the calculated height can be used in Unified Fracture Design module to optimally size the frac treatment honoring height constraints.

Q3D model results are compared with original model to evaluate differences and quantify its superiority over previous algorithms. The use of multilayer model allows the understanding of height growth therefore penetration into unwanted layers can be avoided. As height is also calculated away from wellbore, dipping of fracture or unwanted zone penetration away from the wellbore can also be observed and avoided by adjusting treatment size. Lastly, couple of worked examples are discussed to demonstrate the working of this model. Q3D model allows estimation of frac height in asymmetric multilayer lithology without grouping layers. Further, complete cross-section of height is constructed along the length axis emulating working of 3D models.
Integrating Seismic Inversion and Petrophysical HRA Classes for Reservoir Modeling of Submarine Fluvial Channels
Authors: Ahmad Ammar , Khan Waqar A. , Baig Muhammad Zeeshan
Published: November 2016

In this paper a workflow is presented where seismic inversion facies probability trends along with facies classification from Heterogeneous Rock Analysis (HRA) have been integrated to model the submarine channels to slope fan lobe systems. The slope fans (which were dominantly showing a mix system i.e. sand – shale) and submarine channels were extremely heterogeneous in terms of facies classification. In addition both these depositional systems represented highly variable geomorphology, where fluvial channels ranged from minimum of 5 meters thickness to maximum 15 meters (which represented both amalgamated / stacked channels). The slope fans ranged from few 100's of meter spatial spread to 2 km with sand thickness ranging from 10 – 30 meters.

The challenge in this depositional setting was to map the channels and slope fans both on seismic dataset and then later on to accurately delineate their dimensions and geomorphology. In order to establish the realistic sand thickness parameters using simple geostatistical variograms along with trends maps were not enough therefore, seismic inversion fluvial channel probability cubes were used to determine both the vertical and spatial spread of these depositional patterns.

The petrophysical rock classes derived from the Heterogeneous Rock Analysis method captured the facies variation within these depositional systems very effectively. The HRA classes integrated with the core results captured 4 main rock classes which were; Sand Channels, Channel Levee and Proixmal Slope fan facies (dominantly sands) to distal shalier fractions.

These 4 (Four) facies were then integrated with the inverted seismic results to check for consistency if these were good enough to be calibrated. The seismic inversion resulted in the contruction of several different probability guided trends to maps the fluvial channels and the slope fans. These geomorphological patterns helped in the quantitative delineation of the fluvial channels to the slope fans.

The next step was to analyze the geomorphological parameters of these depositional systems in context of the seismic probability trends. As a result several different orders of fan systems were observed, the largest being several km wide and 2 – 4 km in length while the smallest fan lobes were documented to be having 100 – 200 m spread to 400 – 500 m length. The dimensions of these geobodies were then extracted and integrated into the reservoir model which very effectively captured the facies variation and spatial distribution of these depositional bodies initially based on the seismic inversion results.

The resulting model suggested that only one half of the analyzed reservoir section contained the good quality sands which displayed better communication and connectivity. These sands were then targeted for further field development and lead to the successful testing of the newly drilled well in the area which also lead to opening of a new area for field development.
Workflow for Static Pressure Correction in Gas Condensate Reservoirs – An Improved Approach
Authors: Ali Hamza , Akram Agha Hassan , Khan Waqar A. , Shah Abdur Rahman , Jibran Ali , Bajwa Ali Iqbal
Published: November 2016

In the wellbore, phase segregation and density changes become significant during gauge pressure measurements. Static pressure surveys capture this change in density, provided the gauge is stationed at different depths in the lower part of the tubing, where this change is most expected. These static pressures are then corrected to datum depth to determine the depletion across the field.

Conventionally, a one step pressure correction is used to correct the pressures from the gauge station to datum depth using the wellbore pressure gradient. This approach assumes that the same gradient exists, both in the reservoir and in the wellbore, which is generally not true in the case of gas condensate reservoirs, as well as oil & water producers.

This paper presents a two-step pressure correction workflow for gas condensate reservoirs.It proposes to establish a gradient from pressure measurements acquired from lower gauge stations, as segregated fluid density changes even in the liquid column. This is the wellbore gradient. It makes use of PVT parameters to determine the gradient developed by the reservoir fluid, which is independent of the wellbore gradient, to ensure that the correction to datum depth incorporates the actual reservoir conditions.

It was observed that two step correction, which makes use of reservoir fluid gradient in 2nd step, provides pressure values comparable with formation testing results in contrast to single step corrected pressures. This paper presents a step by step workflow and emphasizes how important it is to make use of actual reservoir conditions while correcting pressure measurements. Advantages and disadvantages of each correction method are also discussed
Improved Porosity – Permeability Relationship Using Data Mining Techniques
Authors: Bashir Muhammad Omer , Dahraj Naeem Ul.
Published: November 2016

It is normally understood in the industry that permeability and porosity are related but relationship can be strong or weak based on heterogeneity, anisotropy and lithology of the reservoir. So far linear models have been arbitrarily being tried to fit and matched with the data thereby resulting in a poor relationship. This paper seeks to explore data mining techniques for pattern recognition including Kohonen self-organizing maps and other unsupervised learning techniques.

Kohonen self-organizing maps and principal component analysis are applied over permeability –porosity data to first cluster the data into various sets. This data can then be linked back to the formations and a predictor can be built thereby giving a tool for reservoir characterization. Then a linear model is to be built with the linearity being assessed by Shapiro Wilk Test and Quantile – Quantile (Q-Q) plot.

This technique develops a relationship with a much better fit between permeability and porosity in respective ranges and thereby creating a higher cue-efficient of determination i.e. R squared value.
Advantages and Disadvantages of Asynchronous Online Extension Programming for Delivering Master Producer Content
Authors: Marble S. Christopher , Fulcher Amy , Toman John
Published: November 2016

Budget reductions for the Cooperative Extension Service have made traditional extension programming (face-to-face, live programming) difficult for extension professionals. Attending traditional extension programming can also prove to be challenging for industry practitioners due to the need to delay or reschedule work activities and the need to travel to participate. The Tennessee Master Nursery Producer program (TMNP) is a professional development extension program designed to enhance the sustainability of the Tennessee nursery crops industry. The TMNP was first offered as a traditional extension program in 2012. Although the program was successful, it demanded substantial time from faculty and staff to coordinate the program, prepare presentations, and travel. Recurring travel expenses required a significant financial commitment from both extension personnel and participants. An asynchronous online program was developed to address these challenges and to increase accessibility, exploit the economies of scale, and standardize curriculum. The objective of this article is to describe the advantages and disadvantages that were identified offering nursery production subject matter as a traditional live classroom and subsequently as an asynchronous online program in terms of development cost, administrative and technological requirements, and economic impacts.
Quantification of uncertainty in reference evapotranspiration climate change signals in Belgium
Authors: Hosseinzadehtalaei Parisa , Tabari Hossein , Willems Patrick
Published: November 2016

Projections of evapotranspiration form the basis of future runoff and water availability assessment in a climate change context. The scarcity of data or insufficiency of time/funds compels the application of simple reference evapotranspiration (ETo) methods requiring less meteorological inputs for ETo projections which adds uncertainty to the projected changes. This study investigates the bias in ETo climate change signals derived from seven simple temperature- and radiation-based methods (Blaney–Criddle, Hargreaves–Samani, Schendel, Makkink, Turc, Jensen–Haise, Tabari) compared with that from the standard Penman–Monteith FAO 56 method on the basis of 12 general circulation model (GCM) outputs from the Coupled Model Intercomparison Project Phase 5 for central Belgium for four future greenhouse gas scenarios (RCP2.6, RCP4.5, RCP6.0, RCP8.5). The results show the lack of conformity on the amount of ETo changes between the simple and standard methods, with biases of over 100% for some simple methods. The uncertainty affiliated with ETo methods for monthly ETo changes is smaller but of comparable magnitude to GCM uncertainty, which is usually the major source of uncertainty, and larger for daily extreme ETo changes. This emphasizes the imperative of addressing the uncertainty associated with ETo methods for quantifying the hydrological response to climate change.
Comparison of particulate pyrite autotrophic denitrification (PPAD) and sulfur oxidizing denitrification (SOD) for treatment of nitrified wastewater
Authors: Tong Shuang , Rodriguez-Gonzalez Laura C. , Feng Chuanping , Ergas Sarina J.
Published: November 2016

The use of reduced sulfur compounds as electron donors for biological denitrification has the potential to reduce chemical and sludge disposal costs as well as carry-over of organic carbon to the effluent that often occurs with heterotrophic denitrification. Although a number of prior studies have evaluated sulfur oxidizing denitrification (SOD), no prior studies have evaluated particulate pyrite autotrophic denitrification (PPAD) in continuous flow systems. Bench-scale upflow packed bed reactors (PBRs) were set up to compare denitrification rates, by-product production and alkalinity consumption of PPAD and SOD. At an empty bed contact time of 2.9 h, average NO3−-N removal efficiencies were 39.7% and 99.9% for PPAD and SOD, respectively. Although lower denitrification rates were observed with PPAD than SOD, lower alkalinity consumption and reduced sulfur by-product formation (SO42−, S2− and SO32− plus S2O32−) were observed with PPAD. Furthermore, higher denitrification rates and lower by-product production was observed for SOD than in prior studies, possibly due to the media composition, which included sand and oyster shells. The results show that both pyrite and elemental sulfur can be used as electron donors for wastewater denitrification in PBRs.
Alternative treatments to improve the potential of rice husk as adsorbent for methylene blue
Authors: Franco Dison S. P. , Tanabe Eduardo H. , Bertuol Daniel A. , dos Reis Glaydson S. , Lima Éder C. , Dotto Guilherme L.
Published: November 2016

Alternative treatments, such as, NaOH, ultrasound assisted (UA) and supercritical CO2 (SCO2), were performed to improve the potential of rice husk as adsorbent to remove methylene blue (MB) from aqueous media. All the treatments improved the surface characteristics of rice husk, exposing its organic fraction and/or providing more adsorption sites. The Langmuir and Hill models were able to explain the MB adsorption for all adsorbents in all studied temperatures. The experimental and modeled parameters demonstrated that the MB adsorption was favored by the temperature increase and by the use of NaOH-rice husk. The maximum adsorption capacities for the MB solutions (ranging from 10 to 100 mg L−1), estimated from the Langmuir model at 328 K, were in the following order: NaOH rice-husk (65.0 mg g−1) > UA-rice husk (58.7 mg g−1) > SCO2-rice husk (56.4 mg g−1) > raw rice husk (52.2 mg g−1). The adsorption was a spontaneous, favorable and endothermic process. In general, this work demonstrated that NaOH, UA and SCO2 treatments are alternatives to improve the potential of rice husk as adsorbent.
УЛЬТРАСТРУКТУРА КЛIТИН СIМ’ЯНИКIВ ЩУРIВ, ЩО ЗАЗНАЛИ ТОКСИЧНОГО ВПЛИВУ ЦИТОСТАТИКА
Authors: Бречка Н. М. , Невзоров В. П. , Невзорова О. Ф. , Бондаренко В. О. , Малова Н. Г.
Published: November 2016

Проведено електронно-мiкроскопiчне дослiдження iнтерстицiальних ендотелiоцитiв, ендоте-лiоцитiв кровоносних капiлярiв i гематотестикулярного бар’єру, клiтин Сертолi та сперматоген-них клiтин сiм’яникiв щурiв, що зазнали впливу цитостатика. Показано, що цитостатик викликаєрозвиток мiтохондрiальної дисфункцiї, зниження активностi п’єзобiосiнтезу, дистрофiчнi тадеструктивнi змiни органел. Цi змiни пов’язанi з розвитком мiтохондрiальної дисфункцiї, яка недозволяє адекватно пiдтримувати високий рiвень бiоенергетичного забезпечення нормальноговнутрiшньоклiтинного метаболiзму. Поряд з цим, вiдсутнiсть деформацiй внутрiшньоклiтиннихмембран вказує на низький рiвень активностi п’єзобiосiнтезу.Ультраструктурна органiзацiя клiтин гематотестикулярного бар’єру сiм’яникiв зазнає ряддеструктивних процесiв пов’язаних з руйнуванням мембран, з пригнiченням п’єзобiосiнтезу.В сперматоцитах знижується ступiнь конденсацiї, спостерiгається вiдшарування акросоми вiдядра, деструкцiя дiлянок плазматичної мембрани джгутикiв, набухання з просвiтленням матри-ксу мiтохондрiй, руйнування крист, вiдсутнiсть дiнеїнових нiжок поблизу дуплетiв мiкротрубо-чок вказує на порушення рухливостi сперматозоїдiв
THE FEATURES OF ACUTE MYOCARDIAL INFARCTION IN PATIENTS WITH TYPE 2 DIABETES AND OBESITY BEFORE AND AFTER REPERFUSION THERAPY
Authors: Bilovol O. M. , Kravchun P. P. , Kadykova O. I. , Rynchàk P. I. , Gabisoniia T. N.
Published: November 2016

The features and central cardiohemodynamics indexes were estimated in patients with acute myocardial infarction, type 2 diabetes and obesity before and after reperfusion therapy. It was examined 58 patients with acute myocardial infarction, type 2 diabetes and obesity. Restoration of coronary blood flow by reperfusion therapy in patients with acute myocardial infarction, type 2 diabetes and obesity positive impacted on the clinical condition of the patient, increases the contractile function of the myocardium and promotes adaptive left ventricular remodeling. In patients with acute myocardial infarction, type 2 diabetes and obesity was found a significant reduction in the incidence of hospitalizations, improve the clinical course of chronic heart failure, coronary reserve increase of the heart after percutaneous coronary intervention compared with thrombolytic therapy.
Cardiovascular Phenotypes in Children with CKD: The 4C Study
Authors: Schaefer Franz , Doyon Anke , Azukaitis Karolis , Bayazit Aysun , Canpolat Nur , Duzova Ali , Niemirska Ana , Sözeri Betul , Thurn Daniela , Anarat Ali , Ranchin Bruno , Litwin Mieczyslav , Caliskan Salim , Candan Cengiz , Baskin Esra , Yilmaz Ebru , Mir Sevgi , Kirchner Marietta , Sander Anja , Haffner Dieter , Melk Anette , Wühl Elke , Shroff Rukshana , Querfeld Uwe ,   for the 4C Study Consortium
Published: November 2016

Background and objectives

Cardiovascular disease is the most important comorbidity affecting long-term survival in children with CKD.

Design, setting, participants, & measurements

The Cardiovascular Comorbidity in Children with CKD Study is a multicenter, prospective, observational study in children ages 6–17 years old with initial GFR of 10–60 ml/min per 1.73 m2. The cardiovascular status is monitored annually, and subclinical cardiovascular disease is assessed by noninvasive measurements of surrogate markers, including the left ventricular mass index, carotid intima-media thickness, and central pulse wave velocity. We here report baseline data at study entry and an explorative analysis of variables associated with surrogate markers.

Results

A total of 737 patients were screened from October of 2009 to August of 2011 in 55 centers in 12 European countries, and baseline data were analyzed in 688 patients. Sixty-four percent had congenital anomalies of the kidney and urinary tract; 26.1% of children had uncontrolled hypertension (24-hour ambulatory BP monitoring; n=545), and the prevalence increased from 24.4% in CKD stage 3 to 47.4% in CKD stage 5. The prevalence of left ventricular hypertrophy was higher with each CKD stage, from 10.6% in CKD stage 3a to 48% in CKD stage 5. Carotid intima-media thickness was elevated in 41.6%, with only 10.8% of patients displaying measurements below the 50th percentile. Pulse wave velocity was increased in 20.1%. The office systolic BP SD score was the single independent factor significantly associated with all surrogate markers of cardiovascular disease. The intermediate end point score (derived from the number of surrogate marker measurements >95th percentile) was independently associated with a diagnosis of congenital anomalies of the kidney and urinary tract, time since diagnosis of CKD, body mass index, office systolic BP, serum phosphorus, and the hemoglobin level.

Conclusions

The baseline data of this large pediatric cohort show that surrogate markers for cardiovascular disease are closely associated with systolic hypertension and stage of CKD.
Biomarkers for the Early Detection and Prognosis of Acute Kidney Injury
Authors: Malhotra Rakesh , Siew Edward D.
Published: November 2016

AKI is an increasingly common disorder that is strongly linked to short- and long-term morbidity and mortality. Despite a growing heterogeneity in its causes, providing a timely and certain diagnosis of AKI remains challenging. In this review, we summarize the evolution of AKI biomarker studies over the past few years, focusing on two major areas of investigation: the early detection and prognosis of AKI. We highlight some of the lessons learned in conducting AKI biomarker studies, including ongoing attempts to address the limitations of creatinine as a reference standard and the recent shift toward evaluating the prognostic potential of these markers. Lastly, we suggest current gaps in knowledge and barriers that may be hindering their incorporation into care and a full ascertainment of their value.
Avaliação do potencial reservatório do cão na Leishmaniose visceral em dois municípios do Estado do Ceará
Authors: Chaves Marlos Medeiros , Teixeira Maria Jânia , Pompeu Margarida Maria Lima , Sousa Raimundo Nonato , Lima José Wellington Oliveira
Published: November 2016

This study had the objective of evaluating the reservoir potential of the dog in visceral leishmaniasis (VL) besides to identify the possible more frequent clinical signs associated to the infectiousness and seropositiveness. Dogs with positive (n=38) and negative (n=11) for the serological ELISA test were studied through xenodiagnosis experiments to determine the infectiousness to phlebotomine vector Lutzomyia longipalpis. Infectiousness for Lu. longipalpis was observed in 36,84% (14) of the dogs from seropositive group and none of the seronegative (p
The Angry Earth
Authors: Barletti Juan Pablo Sarmiento
Published: November 2016

Abstract

In this article, I argue for a broadening of the conceptualisation of wellbeing in the scholarly and policy literature on the topic. I do so as, despite the calls for the inclusion of place in analyses of wellbeing, the literature on the topic still carries a dominant conception of wellbeing as a measurable index based on Euro-American practices and discourses, with their associated views of humanity and nature. I will advance the discussion on wellbeing’s intimate connection to place and place-based consciousness through an ethnographic engagement with kametsa asaiki (‘living well together’), an ethos of wellbeing pursued by indigenous Ashaninka people in the Peruvian Amazon. This is a revealing context as Peru exemplifies how extractive development initiatives tend to misrecognise or underestimate their socio-natural consequences on local pursuits of wellbeing. I argue that an understanding of the role of place and place-based consciousness in wellbeing is key to enhancing the concept’s utility in policy and practice, especially due to its centrality in the United Nations Sustainable Development Goals. In doing so, I call for further ethnographic explorations of the link between wellbeing models and understandings of humanity and nature.
Decanting the Rabelaisian Casks: Accessing Neoplatonic Poetic Fury in Baudelaire's ‘L'Âme du vin’
Authors: Hudson Robert J. , Foote Kristen
Published: November 2016

In one of the lesser-studied sections of Baudelaire's Les Fleurs du Mal, ‘Le Vin’, the poet offers a key to understanding the transcendence necessary for common post-Revolution Parisians to attain the proper poetic inspiration to create elevated verse. Divine or poetic Fury, a theoretically more robust version of other nineteenth-century ideas of intoxication, is at the heart of the section's threshold poem, ‘L'Âme du vin’, and establishes a bridge in Les Fleurs du mal linking the modern terrestrial wanderings of the ‘Tableaux parisiens’ to the celestial flights of the ‘Fleurs du mal’. Developed from Plato's Ion and Gallically codified by Rabelais, these theories filter to the aesthete Baudelaire, who decants this aged wine into a nineteenth-century vessel that lays old regime vertical hierarchies on their side and offers poetic intoxication to all who are willing to labour to become vessels of inspiration themselves.
Bacterial and Fungal Aerosols in Rural Nursery Schools in Southern Poland
Authors: Brągoszewska Ewa , Mainka Anna , Pastuszka Jozef
Published: November 2016

This study aimed to characterize airborne bacteria and fungi populations present in rural nursery schools in the Upper Silesia region of Poland during winter and spring seasons through quantification and identification procedures. Bacterial and fungal concentration levels and size distributions were obtained by the use of a six-stage Andersen cascade impactor. Results showed a wide range of indoor bioaerosols levels. The maximum level of viable bacterial aerosols indoors was about 2600 CFU·m−3, two to three times higher than the outdoor level. Fungi levels were lower, from 82 to 1549 CFU·m−3, with indoor concentrations comparable to or lower than outdoor concentrations. The most prevalent bacteria found indoors were Gram-positive cocci (>65%). Using the obtained data, the nursery school exposure dose (NSED) of bioaerosols was estimated for both the children and personnel of nursery schools. The highest dose for younger children was estimated to range: 327–706 CFU·kg−1 for bacterial aerosols and 31–225 CFU·kg−1 for fungal aerosols. These results suggest an elevated risk of adverse health effects on younger children. These findings may contribute to the promotion and implementation of preventative public health programs and the formulation of recommendations aimed at providing healthier school environments.
Quantum Quasigroups and the Quantum Yang–Baxter Equation
Authors: Smith Jonathan
Published: November 2016

Quantum quasigroups are algebraic structures providing a general self-dual framework for the nonassociative extension of Hopf algebra techniques. They also have one-sided analogues, which are not self-dual. The paper presents a survey of recent work on these structures, showing how they furnish various solutions to the quantum Yang–Baxter equation.
The Receptor Tyrosine Kinase AXL in Cancer Progression
Authors: Rankin Erinn , Giaccia Amato
Published: November 2016

The AXL receptor tyrosine kinase (AXL) has emerged as a promising therapeutic target for cancer therapy. Recent studies have revealed a central role of AXL signaling in tumor proliferation, survival, stem cell phenotype, metastasis, and resistance to cancer therapy. Moreover, AXL is expressed within cellular components of the tumor microenvironment where AXL signaling contributes to the immunosuppressive and protumorigenic phenotypes. A variety of AXL inhibitors have been developed and are efficacious in preclinical studies. These agents offer new opportunities for therapeutic intervention in the prevention and treatment of advanced disease. Here we review the literature that has illuminated the cellular and molecular mechanisms by which AXL signaling promotes tumor progression and we will discuss the therapeutic potential of AXL inhibition for cancer therapy.
Beyond Acute Pain: Understanding Chronic Pain in Infancy
Authors: DiLorenzo Miranda , Pillai Riddell Rebecca , Holsti Liisa
Published: November 2016

This topical review presents the current challenges in defining chronic pain in infants, summarizes evidence from animal and human infant studies regarding the biological processes necessary for chronic pain signaling, and presents observational/experiential evidence from clinical experts. A literature search of four databases (CINAHL, EMBASE, PsycINFO, and MEDLINE) was conducted, along with hand searches of reference lists. Evidence from animal studies suggest that important neurophysiological mechanisms, such as the availability of key neurotransmitters needed for maintenance of chronic pain, may be immature or absent in the developing neonate. In some cases, human infants may be significantly less likely to develop chronic pain. However, evidence also points to altered pain perception, such as allodynia and hyperalgesia, with significant injury. Moreover, clinicians and parents in pediatric intensive care settings describe groups of infants with altered behavioral responses to repeated or prolonged painful stimuli, yet agreement on a working definition of chronic pain in infancy remains elusive. While our understanding of infant chronic pain is still in the rudimentary stages, a promising avenue for the future assessment of chronic pain in infancy would be to develop a clinical tool that uses both neurophysiological approaches and clinical perceptions already presented in the literature.
Genetic Substrate Reduction Therapy: A Promising Approach for Lysosomal Storage Disorders
Authors: Coutinho Maria , Santos Juliana , Matos Liliana , Alves Sandra
Published: November 2016

Lysosomal storage diseases are a group of rare genetic disorders characterized by the accumulation of storage molecules in late endosomes/lysosomes. Most of them result from mutations in genes encoding for the catabolic enzymes that ensure intralysosomal digestion. Conventional therapeutic options include enzyme replacement therapy, an approach targeting the functional loss of the enzyme by injection of a recombinant one. Even though this is successful for some diseases, it is mostly effective for peripheral manifestations and has no impact on neuropathology. The development of alternative therapeutic approaches is, therefore, mandatory, and striking innovations including the clinical development of pharmacological chaperones and gene therapy are currently under evaluation. Most of them, however, have the same underlying rationale: an attempt to provide or enhance the activity of the missing enzyme to re-establish substrate metabolism to a level that is consistent with a lack of progression and/or return to health. Here, we will focus on the one approach which has a different underlying principle: substrate reduction therapy (SRT), whose uniqueness relies on the fact that it acts upstream of the enzymatic defect, decreasing storage by downregulating its biosynthetic pathway. Special attention will be given to the most recent advances in the field, introducing the concept of genetic SRT (gSRT), which is based on the use of RNA-degrading technologies (RNA interference and single stranded antisense oligonucleotides) to promote efficient substrate reduction by decreasing its synthesis rate.
Stearoyl-CoA Desaturase-1 Protects Cells against Lipotoxicity-Mediated Apoptosis in Proximal Tubular Cells
Authors: Iwai Tamaki , Kume Shinji , Chin-Kanasaki Masami , Kuwagata Shogo , Araki Hisazumi , Takeda Naoko , Sugaya Takeshi , Uzu Takashi , Maegawa Hiroshi , Araki Shin-ichi
Published: November 2016

Saturated fatty acid (SFA)-related lipotoxicity is a pathogenesis of diabetes-related renal proximal tubular epithelial cell (PTEC) damage, closely associated with a progressive decline in renal function. This study was designed to identify a free fatty acid (FFA) metabolism-related enzyme that can protect PTECs from SFA-related lipotoxicity. Among several enzymes involved in FFA metabolism, we identified stearoyl-CoA desaturase-1 (SCD1), whose expression level significantly decreased in the kidneys of high-fat diet (HFD)-induced diabetic mice, compared with non-diabetic mice. SCD1 is an enzyme that desaturates SFAs, converting them to monounsaturated fatty acids (MUFAs), leading to the formation of neutral lipid droplets. In culture, retrovirus-mediated overexpression of SCD1 or MUFA treatment significantly ameliorated SFA-induced apoptosis in PTECs by enhancing intracellular lipid droplet formation. In contrast, siRNA against SCD1 exacerbated the apoptosis. Both overexpression of SCD1 and MUFA treatment reduced SFA-induced apoptosis via reducing endoplasmic reticulum stress in cultured PTECs. Thus, HFD-induced decrease in renal SCD1 expression may play a pathogenic role in lipotoxicity-induced renal injury, and enhancing SCD1-mediated desaturation of SFA and subsequent formation of neutral lipid droplets may become a promising therapeutic target to reduce SFA-induced lipotoxicity. The present study provides a novel insight into lipotoxicity in the pathogenesis of diabetic nephropathy.
Biocatalytic Synthesis of Novel Partial Esters of a Bioactive Dihydroxy 4-Methylcoumarin by Rhizopus oryzae Lipase (ROL)
Authors: Kumar Vinod , Mathur Divya , Srivastava Smriti , Malhotra Shashwat , Rana Neha , Singh Suraj , Singh Brajendra , Prasad Ashok , Varma Anjani , Len Christophe , Kuhad Ramesh , Saxena Rajendra , Parmar Virinder
Published: November 2016

Highly regioselective acylation has been observed in 7,8-dihydroxy-4-methylcoumarin (DHMC) by the lipase from Rhizopus oryzae suspended in tetrahydrofuran (THF) at 45 °C using six different acid anhydrides as acylating agents. The acylation occurred regioselectively at one of the two hydroxy groups of the coumarin moiety resulting in the formation of 8-acyloxy-7-hydroxy-4-methylcoumarins, which are important bioactive molecules for studying biotansformations in animals, and are otherwise very difficult to obtain by only chemical steps. Six monoacylated, monohydroxy 4-methylcoumarins have been biocatalytically synthesised and identified on the basis of their spectral data and X-ray crystal analysis.
Double Intramolecular Transacetalization of Polyhydroxy Acetals: Synthesis of Conformationally-Restricted 1,3-Dioxanes with Axially-Oriented Phenyl Moiety
Authors: Asare-Nkansah Samuel , Wünsch Bernhard
Published: November 2016

The synthesis of conformationally-restricted 1,3-dioxanes with a phenyl moiety fixed in an axial orientation at the acetalic center is described. Starting with diethyl 3-hydroxyglutarate (15), benzaldehyde acetal 12a and acetophenone ketal 12b bearing a protected 1,3,5-trihydroxypentyl side chain in the o-position were prepared. The first acid-catalyzed intramolecular transacetalization gave a mixture of diastereomeric 2-benzofurans 18 (ratio of diastereomers 2:2:1:1). After OH group deprotection, the second intramolecular transacetalization afforded tricyclic alcohol 14a (2-(1,5-epoxy-1,3,4,5-tetrahydro-2-benzoxepin-3-yl]ethan-1-ol). Analogous cyclizations led to the corresponding silyl ether 22a (19%) and azide 23a (13%). Whereas tricyclic alcohol 14a was obtained as a 1:1 mixture of diastereomers, the silyl ether 22a and the azide 23a afforded only one diastereomer. This observation indicates a faster cyclization of the minor diastereomers providing the thermodynamically-favored compounds with equatorially-oriented substituents in the 3-position of the tricyclic 1,5-epoxy-2-benzoxepine system. In general, acetophenone-derived ketalic compounds (b-series) required very mild reaction conditions and gave lower yields than the corresponding acetalic compounds (a-series).
Optimal Premium as a Function of the Deductible: Customer Analysis and Portfolio Characteristics
Authors: Thøgersen Julie
Published: November 2016

An insurance company offers an insurance contract ( p , K ) , consisting of a premium p and a deductible K. In this paper, we consider the problem of choosing the premium optimally as a function of the deductible. The insurance company is facing a market of N customers, each characterized by their personal claim frequency, α, and risk aversion, β. When a customer is offered an insurance contract, she/he will, based on these characteristics, choose whether or not to insure. The decision process of the customer is analyzed in detail. Since the customer characteristics are unknown to the company, it models them as i.i.d. random variables; A 1 , … , A N for the claim frequencies and B 1 , … , B N for the risk aversions. Depending on the distributions of A i and B i , expressions for the portfolio size n ( p ; K ) ∈ [ 0 , N ] and average claim frequency α ( p ; K ) in the portfolio are obtained. Knowing these, the company can choose the premium optimally, mainly by minimizing the ruin probability.
Label-Free Fluorescent Detection of Trypsin Activity Based on DNA-Stabilized Silver Nanocluster-Peptide Conjugates
Authors: Zhuo Cai-Xia , Wang Li-Hui , Feng Jing-Jing , Zhang Yao-Dong
Published: November 2016

Trypsin is important during the regulation of pancreatic exocrine function. The detection of trypsin activity is currently limited because of the need for the substrate to be labeled with a fluorescent tag. A label-free fluorescent method has been developed to monitor trypsin activity. The designed peptide probe consists of six arginine molecules and a cysteine terminus and can be conjugated to DNA-stabilized silver nanoclusters (DNA-AgNCs) by Ag-S bonding to enhance fluorescence. The peptide probe can also be adsorbed to the surface of graphene oxide (GO), thus resulting in the fluorescence quenching of DNA-AgNCs-peptide conjugate because of Förster resonance energy transfer. Once trypsin had degraded the peptide probe into amino acid residues, the DNA-AgNCs were released from the surface of GO, and the enhanced fluorescence of DNA-AgNCs was restored. Trypsin can be determined with a linear range of 0.0–50.0 ng/mL with a concentration as low as 1 ng/mL. This label-free method is simple and sensitive and has been successfully used for the determination of trypsin in serum. The method can also be modified to detect other proteases.
The Impact of Sepiolite on Sensor Parameters during the Detection of Low Concentrations of Alcohols
Authors: Suchorska-Woźniak Patrycja , Rac Olga , Fiedot Marta , Teterycz Helena
Published: November 2016

The article presents the results of the detection of low-concentration C1–C4 alcohols using a planar sensor, in which a sepiolite filter was applied next to the gas-sensitive layer based on tin dioxide. The sepiolite layer is composed of tubes that have a length of several microns, and the diameter of the single tube ranges from several to tens of nanometers. The sepiolite layer itself demonstrated no chemical activity in the presence of volatile organic compounds (VOC), and the passive filter made of this material did not modify the chemical composition of the gaseous atmosphere diffusing to the gas-sensitive layer. The test results revealed that the structural remodelling of the sepiolite that occurs under the influence of temperature, as well as the effect of the filter (a compound with ionic bonds) with molecules of water, has a significant impact on the improvement of the sensitivity of the sensor in relation to volatile organic compounds when compared to the sensor without a filter.
Development and Evaluation of Applicable Optimal Terminal Box Control Algorithms for Energy Management Control Systems
Authors: Seong Yoon-Bok , Cho Young-Hum
Published: November 2016

Common energy management control systems (EMCS) in building HVAC systems could be made much more energy efficient without sacrificing comfort. Most researchers have focused on implementing optimal control algorithms in Variable Air Volume (VAV) systems with EMC functions. Previous studies have paid little attention to using terminal box EMC functions integrated with main AHU (Air Handling Unit) systems. Terminal boxes with EMCS may cause occupant discomfort and waste excessive energy if they do not have the proper operation control functions. The objective of this study is to evaluate the impact of energy consumption and estimate building energy savings on the optimal minimum air flow of single duct VAV terminal boxes and develop applicable optimal terminal box control algorithms for EMCS. This paper presents a dynamic model of a VAV terminal box with hydronic reheat, develops optimal terminal box control algorithms and applies the developed EMCS algorithms to an actual building. The results of this study show that optimal terminal box control algorithms can stably maintain the set room air temperature and reduce energy consumption for varying heating loads compared to conventional control algorithms.
Three-Dimensional Rotating Wall Vessel-Derived Cell Culture Models for Studying Virus-Host Interactions
Authors: Gardner Jameson , Herbst-Kralovetz Melissa
Published: November 2016

The key to better understanding complex virus-host interactions is the utilization of robust three-dimensional (3D) human cell cultures that effectively recapitulate native tissue architecture and model the microenvironment. A lack of physiologically-relevant animal models for many viruses has limited the elucidation of factors that influence viral pathogenesis and of complex host immune mechanisms. Conventional monolayer cell cultures may support viral infection, but are unable to form the tissue structures and complex microenvironments that mimic host physiology and, therefore, limiting their translational utility. The rotating wall vessel (RWV) bioreactor was designed by the National Aeronautics and Space Administration (NASA) to model microgravity and was later found to more accurately reproduce features of human tissue in vivo. Cells grown in RWV bioreactors develop in a low fluid-shear environment, which enables cells to form complex 3D tissue-like aggregates. A wide variety of human tissues (from neuronal to vaginal tissue) have been grown in RWV bioreactors and have been shown to support productive viral infection and physiological meaningful host responses. The in vivo-like characteristics and cellular features of the human 3D RWV-derived aggregates make them ideal model systems to effectively recapitulate pathophysiology and host responses necessary to conduct rigorous basic science, preclinical and translational studies.
The CD8+ T Cell-Mediated Immunity Induced by HPV-E6 Uploaded in Engineered Exosomes Is Improved by ISCOMATRIXTM Adjuvant
Authors: Manfredi Francesco , Di Bonito Paola , Ridolfi Barbara , Anticoli Simona , Arenaccio Claudia , Chiozzini Chiara , Baz Morelli Adriana , Federico Maurizio
Published: November 2016

We recently described the induction of an efficient CD8+ T cell-mediated immune response against a tumor-associated antigen (TAA) uploaded in engineered exosomes used as an immunogen delivery tool. This immune response cleared tumor cells inoculated after immunization, and controlled the growth of tumors implanted before immunization. We looked for new protocols aimed at increasing the CD8+ T cell specific response to the antigen uploaded in engineered exosomes, assuming that an optimized CD8+ T cell immune response would correlate with a more effective depletion of tumor cells in the therapeutic setting. By considering HPV-E6 as a model of TAA, we found that the in vitro co-administration of engineered exosomes and ISCOMATRIXTM adjuvant, i.e., an adjuvant composed of purified ISCOPREPTM saponin, cholesterol, and phospholipids, led to a stronger antigen cross-presentation in both B- lymphoblastoid cell lines ( and monocyte-derived immature dendritic cells compared with that induced by the exosomes alone. Consistently, the co-inoculation in mice of ISCOMATRIXTM adjuvant and engineered exosomes induced a significant increase of TAA-specific CD8+ T cells compared to mice immunized with the exosomes alone. This result holds promise for effective usage of exosomes as well as alternative nanovesicles in anti-tumor therapeutic approaches.