bluuebunny/crossref_metadata_2025 huggingface dataset:
THE ANALYSIS OF OIL WELLS CONSTRUCTION IN ABNORMAL CONDITIONS IN EASTERN SIBERIA OIL-FIELDS
Authors: Parfiryev V. A. , Paleyev S. A. , Vaganov Yu. V.
Published: November 2018

The paper presents an analysis of oil wells construction at oil fields of Eastern Siberia. The petrophysical formation cross-section affecting the quality of oil wells construction is characterized. In addition, drilling and casing experience under those mining and geological conditions demonstrates that, as of today, there are no readily available technologies that would afford safe and efficient construction of oil wells in that region. The analysis of the oil wells construction gives grounds to demonstrate indispensability of a comprehensive approach to solving the problems of construction and operation of oil wells at oil fields of the Talakangroup of deposits.
REFINEMENT OF PALEOFACIAL MODEL OF BATHONIAN AGE DEPOSITS IN URNENSKOYE AND UST-TEGUSSKOYE LICENSE AREAS
Authors: Aleksandrov V. M. , Korost D. V. , Ponomarev A. A.
Published: November 2018

By results of the conducted complex analysis geological-geophysical information paleofacies model of the reservoir J2 refined within the Urnenskoye and Ust-Tegusskoye license areas. These sediments accumulated in tidal coast, complicated deltaic complex.
EFFECT OF THERMAL PROPERTIES OF ROCKS TO STEAM STIMULATION
Authors: Durkin S. M. , Menshikova I. N.
Published: November 2018

The results of analysis of effect of thermal properties of rocks to steam stimulation by numerical simulation are considered. Several hydrodynamic models of oil pool of Yarega field with different thermal properties: thermal conductivity and heat capacity of rocks - are created. It concluded that the uncertainty of initial information about thermal properties of rocks can significantly affect on development indicators.
RAPID PHASE TRANSITION AS POTENTIAL HAZARD DURING LNG TRANSPORTATION
Authors: Permyakov V. N. , Shvets V. S.
Published: November 2018

The paper describes the issue of an understudied phenomenon of rapid phase transition (RPT) of liquefied natural gas in case it is released into water: due to a lack of a physic-mathematical model of underwater RPT it is impossible to get qualitative risk assessment of LNG releases into water. The authors analyzed the history of LNG-tanker failures, described the main reasons of the occurrence their failure and analyzed publicly available information about the LNG RPT phenomenon.
GRAINSIZE AND MICROSTRUCTURE OF THE DEPOSITS OF THE KARA SEA SHELF
Authors: Kalashnikova O. S. , Kurchatova A. N. , Slagoda E. A. , Tikhonravova Ya. V.
Published: November 2018

Results of the study samples of offshore deposits of the Kara Sea, taken during VNII Okeangeologia expedition in 2007 are considered in this article. Particle size analysis of samples performed by laser diffraction. Mineralogical analysis was performed by X-ray. The triangular diagram of particle size distribution composition, diagram of the dynamogenetic and diagram of genetic facies for determine the transportation routes of clastic particles have been built by the interpretation of the data, on which lithogenetic types of deposits were identified.
HYDROGEOCHEMICAL CONDITIONSOF WESTERN AND EASTERN MESSOYAKHSK DEPOSITS
Authors: Salnikova Yu. I. , Abdrashitova R. N. , Beshentsev V. A.
Published: November 2018

Hydrogeochemical conditions of the West and East Messoyakhsk fields are discussed in the article. These conditions of the complex hydrogeological Mesozoic basin are important in the formation and preservation of oil and gas deposits. The geological structure is characterized by the presence of a large number of disjunctive dislocations. The fields belong to the Elysion geodynamic water drive system - the Omsk-Gydansk structural zone. This determined the conditions and intensity of oil and gas generation.
FORECAST OF WETTABILITY INDEX IN PRODUCTIVE FORMATIONSBY VOLUME OF RESIDUAL WATER CONTENT
Authors: Akhmetov R. T. , Zeigman Yu. V. , Mukhametshin V. V. , Andreev A. V. , Sultanov Sh. Kh.
Published: November 2018

The paper demonstrates that the hydrophilic behavior of productive formations is primarily determined by the water retaining capacity. Especially it concerns carbonaceous reservoirs characterized by a lack of or low gel cement content. In terrigenous reservoirs the water retaining capacity is greatly affected by the variability of gel cement mineral composition. At a permanent mineral composition of interstitial clay there may be present a correlational relationship between the hydrophilic behavior and water retaining capacity of a productive reservoir.
3D GEOLOGICAL MODELING WITH ACOUNT OF SEDIMENTOLOGICAL CYCLOTHEMS BY THE EXAMPLE OF THE RESERVOIR PK1IN YAMBURGSKOYE FIELD
Authors: Barsukova A. M. , Kazantsev G. V.
Published: November 2018

The analysis has showed the variability of reservoir characteristics in a vertical sense and the bimodal distribution of the porosity. Results that are empirically established in the analysis of the quality of framework was obtained using detailed correlation and separation of facies in reliance on electrometric models byV. S. Muromtsev and core material analysis.
EVALUATION OF THE HYDROCARBON POTENTIALOF LOWER PALEOZOIC SEDIMENTS IN THE NORTH-WESTOF THE EAST EUROPEAN PLATFORM
Authors: Sokolovskiy A. P. , Samitova V. I.
Published: November 2018

A geological model of the structure and accumulation of lower paleozoic sediments in the north-west of the East European platform is overviewed. Prospects of oil and gas potential are estimated and land leases for prospecting wells are marked.
ASPECTS OF OPTIMIZATION OF DRILLING DIRECTIONAL WELLS
Authors: Kuznetsov V. G. , Grechin E. G. , Nikiforov D. A. , Savin E. N.
Published: November 2018

Analysis of the Russian and foreign expertisein optimizing the drilling process suggeststhe need to develop new methods for solving the problems associated with the process of drilling directional wells, in order to prevent possible complications and on their basis solvethe optimization problems in the field of drilling, which seems a relevant scientific and practical task.
EFFECT OF PHYSICOCHEMICAL PROPERTIES OF ASPHALT-RESIN-PARAFFIN COMPONENTS ON THE INTENSITY OF THE FORMATION OF ASPHALT-RESIN-PARAFFIN DEPOSITS
Authors: Bayda A. A. , Grebnev A. N. , Mozyrev A. G. , Agaev S. G.
Published: November 2018

There was obtained an empirical equation describing the relationship between the intensity of the formation of asphalt-resin-paraffin deposits and physicochemical properties of asphalt-resin-paraffin components. The intensity of the formation of the asphalt-resin-paraffin deposits is a function of the melting temperature and density of asphalt-resin-paraffin components. The equation is valid for the formation of a paraffin type deposits in the asphalt-resin-paraffin components melting temperature range from 65.0 to 91.2 °C and their density from 0,799 to 0.851.
ON THE POSSIBILITY OF CLARIFYING THE TECTONIC ZONING OF NIZHNEVARTOVSKY ARCH AND ALEKSANDROVSKY MEGASWELL BASED ON THE CORRELATION ANALYSISOF STRATIGRAPHIC BOUNDARIES
Authors: Kekhter Ya. R.
Published: November 2018

The paper presents the problem of studying the sedimentary basins of the Nizhnevartovsky arch and Aleksandrovsky megswell. In particular, the main task at first is to establish zones of maximum accumulation of sediments, the total thickness of the sedimentary discharge of the basin and its boundaries (study of the depths of the occurrence, that is the relief of the surface of the basement). On the basis of the existing catalog of stratigraphic breakdowns it is suggested to claryfy them, to analyze the tectonic development and growth of structures.
PROBLEMS OF COMPATIBILITY OF FORMATION WATER AND INJECTED WATER IN THE OIL FIELDS OF WESTERN SIBERIA
Authors: Semenova T. V.
Published: November 2018

A method of maintaining reservoir pressure using a system for formation pressure maintenance of oil reservoirs in the oil fields of Western Siberia is extremely wide-spread. In oil fields as a system for formation pressure maintenance are widely used almost all types of water resources including surface water, groundwater and industrial wastewater. Different calculation methods for predicting the formation and precipitation of salts based on quantitative criteria are used to forecast possible precipitation of calcium carbonate in the flooded oil reservoir areas.
MATERIAL COMPOSITION AND PROSPECTS OF OIL AND GAS BEARING OF TRIASSIC AND PERMIAN-TRIASSIC SEDIMENTS IN THE WEST OF THE TERRITORY OF KHANTY-MANSIYSK AUTONOMOUS OKRUG - UGRA
Authors: Yakovleva N. P. , Myasnikova G. P. , Chernova G. A.
Published: November 2018

In the paper the material composition of volcanic-sedimentary Triassic and Permian-Triassic sediments of Severo-Sosvinsky and Sherkalinsky grabens is considered. The scheme of distribution of Triassic and Permian-Triassic sediments of the western territory of Khanty-Mansiysk Autonomous Okrug - Ugra is presented. The sections of the wells, that have revealed the sediments, specific for grabenlike depressions, are described. The oil and gas content of volcanic-sedimentary sediments of Permian-Triassic age in the west of Khanty-Mansiysk Autonomous Okrug - Ugra was analyzed.
LITOLOGICAL CHARACTERISTIC OF ONE OF LAYERS OF UPPERJURASSIC SEDIMENTS OF THE T FIELD
Authors: Begma D. S. , Belkina V. A.
Published: November 2018

The relevance of the discussed issue is predetermined by the fact that almost all geological issues are solved on the basis of the models, which accuracy increases considerably, when using sedimentological component. Sedimentological factors control the conditions of formation, placement and quality of a reservoir and caps. It means that consideration of sedimentological models increases the efficiency of exploration for oil and gas, particularly the preparation of sediments for development and their operational drilling.
PERFECTION OF THE PYROLYSIS PROCESS
Authors: Magaril E. R. , Magaril R. Z. , Trushkova L. V.
Published: November 2018

There were obtained the values of the relative reactivity of different types of bonds in interaction with hydrogen atoms, methyl radicals, as well as values of the effective relative reactivity when using an inert diluent, enabling to improve knowledge about the pyrolysis of raw materials of a given composition. A method was developed for increasing the selectivity of the pyrolysis for the desired products of the process (lower olefins), reducing the yield of liquid products of condensation and specific energy consumption, based on the influence of hydrogen on the thermal reactions of alkanes and alkenes.
POSSIBILITIES OF MODELING OF COMPOSITIONS OF ALLOYS Fe-Ni-Co AIMING TO FORECAST THE PHASE TRANSFORMATIONS
Authors: Zhilin A. S. , Newkirk J. W. , Amine T. .. , Ramazanova V. R. , Tokarev V. V.
Published: November 2018

In the paper the possibility of use of computational modeling for prediction of processes of phase transformation by example of small series of Fe-Ni-Co alloys has been shown. Due to complexity of structure for-mation processes in these alloys the relation between modeling and experimental work was described. Modeling allows to predict basic transformations in alloys, but it doesn`t display the real composition of structural components.
RESEARCH OF NON-STATIONARY THERMAL FIELD IN RESERVOIRAND WELLBORE WITH MULTIPHASE FILTRATION
Authors: Kanafin I. V. , Sharafutdinov R. F. , Zakirov M. F. , Ramazanov A. Sh.
Published: November 2018

In the paper the mathematical formulation of a task of temperature filed in the wellbore and reservoir sys-tem with multiphase fluid filtration is considered. The mathematical models of two-phase non-isothermal filtration of fluid in porous media are described, which take into account non-stationary thermo hydrodynamic processes, barothermic effect, oil degassing when reservoir pressure lowers below saturation pressure. The mathematical models are developed for two-phase flow in vertical wellbore. The paper shows the results of numerical solution of formation of temperature field in reservoir and wellbore system and testing results on analytical solutions.
FEATURES OF GEOLOGICAL STRUCTURE AND PETROLEUM POTENTIAL OF CARBONATE SEDIMENTS ON THE WEST SIBERIAN PLATE TERRITORY
Authors: Moroz M. L. , Tugareva A. B.
Published: November 2018

The article considers the wells that have penetrated the carbonate sediments with the geological and paleontological information. By the late Devonian epoch paleogeographic scheme they are located in certain megazones with their inherent characteristics of sedimentation. Examples of lateral relations of carbonate or shalecarbonate rocks with subordinate volcanic rocks on Lovinsky and Khanty-Mansi areas are given. A variety of types of carbonate rocks is associated with structural features of basins in which there was sedimentation, as well as various secondary processes. Based on new geological information, obtained in recent years on Galyanovsk, South Galyanovsk, Khanty-Mansi and other areas, the areas of distribution of carbonate deposits within the Frolovskaya megadepression are clarified. Their petroleum potential is associated with reef structures is mostly confined to near rim parts of the deep depressions of the basement, a reliable mapping of which is possible with more detailed geophysical work.
ANALYSIS OF INCREASING IN WELLS PRODUCTIVITY AFTER HYDRAULIC FRACTURING
Authors: Abass S. Y.
Published: November 2018

In the article an analysis was made of the flow characteristics of fluids at different fracture points formed as a result of hydraulic fracturing of the formation. The effect of damaged formations on the filtration properties of the formation and the behavior of fluids in the fracture and how the flow rate decreases as a result of the destroyed formation were also studied.
CALCULATION OF OPTIMAL INJECTION RATE FOR DISPERSED WATERFLOODING SYSTEM
Authors: Vaganov L. A. , Sencov A. Yu. , Ankudinov A. A. , Polyakova N. S.
Published: November 2018

The article presents a description of the settlement method of necessary injection rates calculation, which is depended on the injected water migration into the surrounding wells and their mutual location. On the basis of the settlement method the targeted program of geological and technical measures for regulating the work of the injection well stock was created and implemented by the example of the BV7 formation of the Uzhno-Vyintoiskoe oil field.
FEATURES OF APPLICATION OF MODEL OF THE STATIONARY TWO-PHASE FILTRATION FOR OIL FIELDS DEVELOPMENT
Authors: Korotenko V. A. , Grachev S. I. , Kushakova N. P.
Published: November 2018

The article discusses the differential equation of the stationary two-phase filtration, the obtained as a spe-cial case of nonlinear non-stationary equations. It is established that for the formulation of solutions it is necessary to use the dependence of water-saturation and oil-saturation factors on the pressure of water pumped into the reservoir. With the advance bringing into the development of the injection well, it has been established, that the water and oil flow rates and the water-cut coefficient depend on the selected coefficients of the relative permeability and the outer boundary of the drainage area. The merits and demerits of the stationary filtration model are estimated.
BERRIASIAN-HAUTERIVIAN SHALE SEQUENCE AND ASSOCIATED PINCH-OUT TRAP PROSPECTS OF THE YAMAL PENINSULA
Authors: Kurkin A. A. , Yankova N. V. , Kuznetsov V. I. , Stulikov S. K.
Published: November 2018

Based on detailed seismic and well data interpretation, a Berriasian-Early Hauterivian voskhodnaya sequence of shale was distinguished as a part of Akhskaya suite in the south-west of the Yamal Peninsula. Subsequent conventional west dipping clinoforms are pinching-out on the top of the sequence, forming stratigraphic traps, characterized by seismic anomalies. Hydrocarbon prospectivity of the traps is proved by well tests.
VERTICAL HYDRODYNAMIC ZONING OF THE YAMAL-KARA DEPRESSION (NORTHERN AREAS OF WESTERN SIBERIA)
Authors: Novikov D. A.
Published: November 2018

The article presents the study results of hydrodynamic zoning of hydrocarbon reservoirs of the Yamal-Kara depression located in the north West Siberian megabasin. The study area has two types of natural water-driven systems: expelled system (geostatic and geodynamic) in the basin centre and infiltration system in the basin margins. Piezominimum zones extending along the main oil and gas seeps (Bolshayakheta and Kara megasyneclises) have been found that correspond to the largest petroleum plays (Vankor-Suzunskaya, Bovanenkovskaya, Urengoiskaya and others).
GENERAL CLASSIFICATION OF UNDERGROUND GAS STORAGES
Authors: Arsan Sh. A. , Yagafarov A. K. , Vaganov Yu. V.
Published: November 2018

The article contains general information about Underground Gas Storages (UGS). The classification of Underground Gas Storage facilities is suggested, according to the operating regime and their purpose, as well as general classification of UGS.
JUSTIFICATION OF THE CHOICE OF EFFECTIVE SYSTEM OF AUTOMATICFIRE EXTINGUISHING IN THE COMPRESSOR DEPARTMENT
Authors: Omelchuk M. V. , Korotkova Yu. S. , Vorontsova A. O.
Published: November 2018

The article considers fire extinguishing systems in the compressor departments, the analysis of advantages and disadvantages each of them. Scientific justification of the choice of system of au-tomatic fire extinguishing is given. The most of effective system of automatic fire extinguishing in the compressor department is usage of gas fire extinguishing with using of FK-5-1-12 Freon. The author presents the example of calculation of mass of this fire extinguishing agent necessary for fire suppression in the compressor department of 18 000 m3.
INNOVATIONS AND RENOVATIONS OF ENHANCED OIL RECOVERY BY ACOUSTIC FIELDS
Authors: Shatalova N. V.
Published: November 2018

The article present a survey of the current status of the oil industry raw materials base, trends and results of research of an acoustic technology, using of the borehole technical noise. The aim of the research is a theoretical justification and innovative solutions development of acoustic waves transforming and applying them for improving of standards of hydrocarbon production perfor-mance without using of additional energy sources. As an example, the approved acoustic technologies, developed by applying of new methods to the deep investigated acoustic phenomenon - standing acoustic waves, are used. The result is a substantiation of a new acoustic technology, which is developed by means of innovative and renovative technical solutions.
INFLUENCE OF THE TIME STORAGE OF ICE POWDER ON KINETICS OF FORMATION AND GROWTH OF FREON-12 GAS HYDRATE
Authors: Madygulov M. Sh. , Zavodovsky A. G. , Shchipanov V. P.
Published: November 2018

The article explores the influence a storage time on the samples of pure ice powder and mod-ified ice powder with polyvinylpyrrolidone on process formation and growth of the gas hydrate by used P-V-T measurements. It has been established that increased storage time of the pure ice powder leads to a decrease the rate of growth of gas hydrate. Fresh modified ice powder has induction time of hydrate formation which increased in a polyvinylpyrrolidone concentration. At long-term storage of modified ice powder with a polyvinylpyrrolidone concentration less 0,3 % the induction time don’t registrate and growth rate of gas hydrate likes zero. In the samples of modified ice powder with a polyvinylpyrrolidone concentration more 0,75 % after 10 days a storage were retained growth rate of gas hydrate likes fresh modified ice powder. There is no induction effect.
DEVELOPMENT OF METHODOLOGICAL BASIS I4.0 FOR PRODUCTION SYSTEMS OF OIL REFINING INDUSTRY
Authors: Andieva E. Yu. , Tolkacheva E. V.
Published: November 2018

The article suggests a formal presentation of the concept with the intentional usage of mnemonic names, which forms the methodological basis for the introduction of I4.0 for production systems of the oil refining industry. The concept is based on definition and formal representation of the digital twin of a production system of production of oil products and control systems of this production system. The article contains new terms and definitions that significantly affect the presentation of the processes of digitizing production systems in the oil refining industry.
HYDROGEOCHEMICAL CONDITIONS OF THE MESOZOIC HYDROGEOLOGICAL BASIN IN THE TERRITORY OF THE YARUDEY OIL AND GAS CONDENSATE FIELD
Authors: Beshentsev V. A. , Sabanina I. G. , Beshentseva O. G. , Abdrashitova R. N.
Published: November 2018

Hydrogeochemical conditions of the Yarudey oil and gas condensate field are largely determined by its position within the elysion lithostatic water pressure system and the presence of a large number of faults in the base plate. In the article we explore the main features of the Neocomian and the Jurassic hydrogeological complexes of the field. Underground waters of the Mesozoic hydrogeological basin are characterized by chloride sodium ion-salt composition. They belong to the hydrocarbonate sodium type according to V. A. Sulin’s classification, mineralization is 7,0 g/l in the Neocomian complex and is 11,1 g/l in the Jurassic complex. The existence of complex hydrogeochemical conditions is confirmed by the nature of the change in the genetic sodiumchlorine coefficient (up to 1,4) and boron-bromine coefficients (up to 0,49).
SYNTHESIS AND PROPERTIES OF EMULSIFIERS OF INVERT EMULSIONS BASED ON FATTY ACID MONOETHANOLAMIDES
Authors: Ovchinnikov V. P. , Talanov I. A. , Yakovlev I. G. , Gerasimov D. S. , Rozhkova V. ..
Published: November 2018

The article discusses the results of synthesis of various derivatives of carboxylic acids and ethanolamine, namely monoethanolamides of stearic and tridecanoic acids. We used azeotropic distillation method for the synthesis. This research allows to value applicability of monoethanolamides as emulsifier invert emulsion.
The 50 most cited publications in endoscopic third ventriculostomy: a bibliometric analysis
Authors: Zagzoog Nirmeen , Attar Ahmed , Reddy Kesh
Published: November 2018

OBJECTIVE

Although endoscopic third ventriculostomy (ETV) for the treatment of hydrocephalus was introduced in 1923, the method was relegated to the sidelines in favor of extracranial techniques. Since the 1990s to the beginning of the current century, however, ETV has undergone a remarkable resurgence to become the first-line treatment for obstructive hydrocephalus, and for some groups, the procedure has been applied for communicating hydrocephalus as well. In the present study, the authors identified the top 50 cited ETV works. These articles represent works of significance that document current practices and provide guidance for future inquiry.

METHODS

The top 50 cited articles pertaining to ETV were identified using bibliometric data obtained with the Harzing’s Publish or Perish software search engine. These high-impact works were evaluated for publication properties including year, country of authorship, category, and journal.

RESULTS

The top 50 works were cited an average of 141.02 times with a mean of 9.45 citations per year. Articles published in 2005 were the most numerous in the top 50 group. These top articles were most frequently published in the Journal of Neurosurgery: Pediatrics. Most of the articles were clinical studies reporting on patients in the pediatric age group. The country of most authorship was the US, although many other countries were among the top 50 works.

CONCLUSIONS

The present report discusses the bibliometric analysis of the top 50 ETV articles. This list may be useful to those interested in the progress and current status of this procedure.
Assessment of costs in open surgery and stereotactic radiosurgery for vestibular schwannomas
Authors: Abou-Al-Shaar Hussam , Azab Mohammed A. , Karsy Michael , Guan Jian , Alzhrani Gmaan , Gozal Yair M. , Jensen Randy L. , Couldwell William T.
Published: November 2018

OBJECTIVE

Microsurgical resection and radiosurgery remain the most widely used interventions in the treatment of vestibular schwannomas. There is a growing demand for cost-effectiveness analyses to evaluate these two treatment modalities and delineate the factors that drive their total costs. Here, the authors evaluated specific cost drivers for microsurgical and radiosurgical management of vestibular schwannoma by using the Value Driven Outcomes system available at the University of Utah.

METHODS

The authors retrospectively reviewed all cases involving microsurgical and radiosurgical treatment of vestibular schwannomas at their institution between November 2011 and September 2017. Patient and tumor characteristics, subcategory costs, and potential cost drivers were analyzed.

RESULTS

The authors identified 163 vestibular schwannoma cases, including 116 managed microsurgically and 47 addressed with stereotactic radiosurgery (SRS). There were significant differences between the two groups in age, tumor size, and preoperative Koos grade (p < 0.05), suggesting that indications for treatment were markedly different. Length of stay (LOS) and length of follow-up were also significantly different. Facility costs were the most significant contributor to both microsurgical and SRS groups (58.3% and 99.4%, respectively); however, physician professional fees were not specifically analyzed. As expected, microsurgical treatment resulted in an average 4-fold greater overall cost of treatment than for SRS cases (p < 0.05), and there was a greater variation in costs for open cases as well. Costs remained stable over time for both open resection and SRS. Multivariable analysis showed that LOS (β = 0.7, p = 0.0001), discharge disposition (β = 0.2, p = 0.004), nonserviceable hearing (β = 0.1, p = 0.02), and complications (β = 0.2, p = 0.005) affected cost for open surgery, whereas no specifically examined factor could be identified as driving costs for SRS.

CONCLUSIONS

This analysis identified the fact that facility utilization constitutes the majority of total costs for both microsurgery and SRS treatment modalities of vestibular schwannomas. LOS, discharge disposition, nonserviceable hearing, and complications contributed significantly to the total costs for the microsurgical group, whereas none of the factors could be identified as driving total costs for the SRS group. This information may be used to establish policies and protocols to reduce facility costs, with the goal of decreasing the total costs without jeopardizing patient care.
Comparing costs of microsurgical resection and stereotactic radiosurgery for vestibular schwannoma
Authors: Schnurman Zane , Golfinos John G. , Epstein David , Friedmann David R. , Roland J. Thomas , Kondziolka Douglas
Published: November 2018

OBJECTIVE

Given rising scrutiny of healthcare expenditures, understanding intervention costs is increasingly important. This study aimed to compare and characterize costs for vestibular schwannoma (VS) management with microsurgery and radiosurgery to inform practice decisions and appraise cost reduction strategies.

METHODS

In conjunction with medical records, internal hospital financial data were used to evaluate costs. Total cost was divided into index costs (costs from arrival through discharge for initial intervention) and follow-up costs (through 36 months) for 317 patients with unilateral VSs undergoing initial management between June 2011 and December 2015. A retrospective matched cohort based on tumor size with 176 patients (88 undergoing each intervention) was created to objectively compare costs between microsurgery and radiosurgery. The full sample of 203 patients treated with resection and 114 patients who underwent radiosurgery was used to evaluate a broad range of outcomes and identify cost contributors within each intervention group.

RESULTS

Within the matched cohort, average index costs were significantly higher for microsurgery (100% by definition, because costs are presented as a percentage of the average index cost for the matched microsurgery group; 95% CI 93–107) compared to radiosurgery (38%, 95% CI 38–39). Microsurgery had higher average follow-up costs (1.6% per month, 95% CI 0.8%–2.4%) compared to radiosurgery (0.5% per month, 95% CI 0.4%–0.7%), largely due to costs incurred in the initial months after resection. A major contributor to total cost and cost variability for both resection and radiosurgery was the need for additional interventions in the follow-up period, which were necessary due to complications or persistent functional deficits. Although tumor size was not associated with increased total costs for radiosurgery, linear regression analysis demonstrated that, for patients who underwent microsurgery, each centimeter increase in tumor maximum diameter resulted in an estimated increase in total cost of 50.2% of the average index cost of microsurgery (95% CI 34.6%–65.7%) (p < 0.001, R2 = 0.17). There were no cost differences associated with the proportion of inpatient days in the ICU or with specific surgical approach for patients who underwent resection.

CONCLUSIONS

This study is the largest assessment to date based on internal cost data comparing VS management with microsurgery and radiosurgery. Both index and follow-up costs are significantly higher when tumors were managed with resection compared to radiosurgery. Larger tumors were associated with increased resection costs, highlighting the incremental costs associated with observation as the initial management.
Coil and Onyx embolization of a torcular herophili dural arteriovenous fistula in a full-term neonate with advanced heart failure using a transumbilical approach
Authors: Koutsouras George W. , Rahmani Redi , Schmidt Tyler , Silberstein Howard , Bhalla Tarun
Published: November 2018

Neonatal dural arteriovenous fistulas (DAVFs) are rare, but if left untreated will advance to life-threatening neurological and cardiovascular compromise. Endovascular treatment is the preferred treatment modality for DAVFs. The goal of endovascular therapy is to obliterate feeding vasculature and prevent secondary complications. Endovascular access can be difficult to obtain in a neonate. The authors present the case of a full-term, normal birth weight neonate with severe congestive heart failure secondary to a congenital DAVF of the torcular herophili that was successfully treated with transumbilical arterial coil embolization and a liquid embolic agent.
Case-matched comparative analysis of spinal deformity correction in arthrogryposis multiplex congenita versus adolescent idiopathic scoliosis
Authors: Xu Liang , Chen Zhonghui , Qiu Yong , Chen Xi , Li Song , Du Changzhi , Zhou Qingshuang , Sun Xu
Published: November 2018

OBJECTIVE

As scoliosis in arthrogryposis multiplex congenita (AMC) is unusual and the number of cases reviewed in previous studies is also relatively small, no previous study exists that has directly compared the results of spinal deformity correction between AMC and adolescent idiopathic scoliosis (AIS) patients. The aim of this study was to compare the radiographic and clinical outcomes of surgical correction of spinal deformity associated with AMC versus AIS.

METHODS

Twenty-four adolescents with AMC were matched with 48 AIS patients in terms of Cobb angle of main curve, curve pattern, sex, age at surgery, Risser grade, and length of follow-up. Patients in both groups underwent posterior-only spinal correction and fusion procedures. The surgical outcomes and complications were analyzed and compared between the 2 groups.

RESULTS

In comparison to the AIS group, the AMC group had a significantly longer mean operation time (5.6 vs 4.4 hours, p = 0.002), more blood loss (1620 ± 250 ml vs 840 ± 260 ml, p < 0.001), and more fusion levels (14.1 ± 2.3 levels vs 12.4 ± 2.5 levels, p = 0.007) as well as a lower correction rate (44.3% ± 11.1% vs 70.8% ± 12.4%, p < 0.001) and a higher rate of loss of correction (5.0% ± 3.1% vs 2.1% ± 1.9%, p < 0.001). Nine patients in the AMC group had preoperative pelvic obliquity, which was corrected from a mean of 14.2° ± 8.4° to a mean of 4.3° ± 3.2° (p < 0.001) after the surgery. The thoracic lordosis and sagittal vertical axis were significantly improved in the AMC group. Notably, however, the AMC group was found to have higher rates of screw malpositioning (15.9% vs 9.5%, p = 0.002) and complications (8/24 [33.3%] vs 4/48 [8.3%], p = 0.016) as compared to the AIS group.

CONCLUSIONS

Correction of AMC-associated scoliosis tends to require a longer operating time and involve more fusion levels but results in less correction, more blood loss, and more complications, in comparison with AIS. In addition, more attention should be paid to pelvic obliquity and sagittal hyperlordosis in AMC patients.
Rapid cardiac ventricular pacing to facilitate embolization of vein of Galen malformations: technical note
Authors: Hockley Aaron , Tso Michael K. , Almekhlafi Mohammed A. , Lodha Abhay K. , Clegg Robin , Luntley Jeremy , Eesa Muneer , Wong John H.
Published: November 2018

OBJECTIVE

Vein of Galen aneurysmal malformations (VGAMs) in infancy have a poor natural history if left untreated. Their high-flow nature can preclude safe and accurate therapeutic vessel occlusion and the risk of inadvertent pulmonary embolism is predominant. The authors describe the technique of rapid cardiac ventricular pacing for inducing transient hypotension to facilitate the controlled embolization of VGAMs.

METHODS

Initial transjugular venous access was obtained for placing temporary pacing leads for rapid cardiac ventricular pacing immediately prior to embolization. Definitive transarterial embolization procedures for the VGAMs were then performed in the same setting in which liquid embolic agents or coils were used.

RESULTS

Beginning in 2010, a total of five procedures were performed in three infants. Transvenous rapid cardiac ventricular pacing was successfully achieved to induce systemic transient flow arrest in all but two attempts, and facilitated partial embolization with n-butyl cyanoacrylate (n-BCA) and coils in all procedures. Ventricular fibrillation occurred twice in one patient and was successfully reversed with defibrillation on both occasions. One patient failed to improve and died from refractory heart failure. Two patients stabilized following staged embolization.

CONCLUSIONS

Rapid transvenous cardiac ventricular pacing can be considered to induce transient hypotension and facilitate controlled embolization in challenging high-flow VGAMs.
Endoscope-assisted (with robotic guidance and using a hybrid technique) interhemispheric transcallosal hemispherotomy: a comparative study with open hemispherotomy to evaluate efficacy, complications, and outcome
Authors: Chandra P. Sarat , Subianto Heri , Bajaj Jitin , Girishan Shabari , Doddamani Ramesh , Ramanujam Bhargavi , Chouhan Mahendra Singh , Garg Ajay , Tripathi Madhavi , Bal Chandrasekhar S. , Sarkar Chitra , Dwivedi Rekha , Sapra Savita , Tripathi Manjari
Published: November 2018

OBJECTIVE

Endoscope-assisted hemispherotomy (EH) has emerged as a good alternative option for hemispheric pathologies with drug-resistant epilepsy.

METHODS

This was a prospective observational study. Parameters measured included primary outcome measures (frequency, severity of seizures) and secondary outcomes (cognition, behavior, and quality of life). Blood loss, operating time, complications, and hospital stay were also taken into account. A comparison was made between the open hemispherotomy (OH) and endoscopic techniques performed by the senior author.

RESULTS

Of 59 cases (42 males), 27 underwent OH (8 periinsular, the rest vertical) and 32 received EH. The mean age was 8.65 ± 5.41 years (EH: 8.6 ± 5.3 years; OH: 8.6 ± 5.7 years). Seizure frequency per day was 7 ± 5.9 (EH: 7.3 ± 4.6; OH: 15.0 ± 6.2). Duration of disease (years since first episode) was 3.92 ± 1.24 years (EH: 5.2 ± 4.3; OH: 5.8 ± 4.5 years). Number of antiepileptic drugs per patient was 3.9 ± 1.2 (EH: 4.2 ± 1.2; OH: 3.8 ± 0.98). Values for the foregoing variables are expressed as the mean ± SD. Pathologies included the following: postinfarct encephalomalacia in 19 (EH: 11); Rasmussen’s syndrome in 14 (EH: 7); hemimegalencephaly in 12 (EH: 7); hemispheric cortical dysplasia in 7 (EH: 4); postencephalitis sequelae in 6 (EH: 2); and Sturge-Weber syndrome in 1 (EH: 1). The mean follow-up was 40.16 ± 17.3 months. Thirty-nine of 49 (79.6%) had favorable outcomes (International League Against Epilepsy class I and II): in EH the total was 19/23 (82.6%) and in OH it was 20/26 (76.9%). There was no difference in the primary outcome between EH and OH (p = 0.15). Significant improvement was seen in the behavioral/quality of life performance, but not in IQ scores in both EH and OH (p < 0.01, no intergroup difference). Blood loss (p = 0.02) and hospital stay (p = 0.049) were less in EH.

CONCLUSIONS

EH was as effective as the open procedure in terms of primary and secondary outcomes. It also resulted in less blood loss and a shorter postoperative hospital stay.
Ruptured intracranial aneurysm in a patient with autosomal recessive polycystic kidney disease
Authors: Perez Jennifer L. , McDowell Michael M. , Zussman Benjamin , Jadhav Ashutosh P. , Miyashita Yosuke , McKiernan Patrick , Greene Stephanie
Published: November 2018

Aneurysmal rupture can result in devastating neurological consequences and can be complicated by comorbid disease processes. Patients with autosomal recessive polycystic kidney disease (ARPKD) have a low rate of reported aneurysms, but this may be due to the relative high rate of end-stage illnesses early in childhood. Authors here report the case of a 10-year-old boy with ARPKD who presented with a Hunt and Hess grade V subarachnoid hemorrhage requiring emergency ventriculostomy, embolization, and decompressive craniectomy. Despite initial improvements in his neurological status, the patient succumbed to hepatic failure. Given the catastrophic outcomes of subarachnoid hemorrhage in young patients, early radiographic screening in those with ARPKD may be warranted.
Management of hydrocephalus in infants with severe hemophilia A: report of 2 cases
Authors: Bergin Stephen M. , Dunn Amy L. , Smith Luke G. F. , Drapeau Annie I.
Published: November 2018

The authors report on the clinical course of two infants with severe hemophilia A (HA) and concomitant progressive hydrocephalus that required management with a ventriculoperitoneal shunt. The first child, with known HA, presented with a spontaneous intracranial hemorrhage and acquired hydrocephalus. He underwent cerebrospinal fluid diversion with a temporary external ventricular drain, followed by placement of a ventriculoperitoneal shunt. The second child had hydrocephalus secondary to a Dandy-Walker malformation and was diagnosed with severe HA during preoperative evaluation. He underwent placement of a ventriculoperitoneal shunt after progression of the hydrocephalus. The authors also review the treatment of hydrocephalus in patients with HA and describe the perioperative protocols used in their two cases. Treatment of hydrocephalus in infants with HA requires unique perioperative management to avoid complications.
Nivelacijski
plan kružnih raskrižja kao sadržaj projekata javnih cesta
Authors: Pevalek Veljko , Barišić Ivica , Pilepić Damir
Published: November 2018

U radu se daje analiza i usporedba visinskog vođenja klasičnih raskrižja
u jednoj razini i kružnih raskrižja te se detektira problem neusklađenosti regulative koja propisuje obavezan sadržaj projekata za javne ceste koji se odnosi na raskrižja. Također se daju neki primjeri načina grafičkog prikaza kružnog raskrižja kao dijela sadržaja projekata
za javne ceste te potrebnih točaka iskolčenja kružnih raskrižja. Kako su se u Hrvatskoj donedavno na mjestima križanja prometnih tokova dominantno primjenjivala klasična raskrižja u jednoj razini, tako su i kod sudionika u gradnji ostali neki zahtjevi koji su neprimjenjivi za kružna raskrižja i kod zadavanja projektnih zadataka i kod izrade nacrta
kojim bi se obradilo visinsko vođenje kružnog raskrižja. Kružna raskrižja imaju različitu geometriju te su zbog toga i različiti ulazni podatci koji su potrebni za računalne programe za projektiranje prometnica od onih za projektiranje klasičnog raskrižja u jednoj razini.
Svrha izrade članka je ukazati na aktualna pitanja i probleme kod projektiranja kružnih raskrižja, dok je cilj rada preporuka sadržaja koji projekt javne ceste mora imati u slučaju projektiranja kružnog raskrižja.
Povećanje održive mobilnosti uporabom sustava Personal Rapid
Transit
Authors: Tomić Ivana , Barišić Ivica , Pilepić Damir
Published: November 2018

Neupitno je da promet negativno utječe na okoliš: onečišćuje zrak, vodu,
tlo, podiže razinu buke i vibracije, djeluje na klimatske promjene, ali
i na ljudsko zdravlje. Povećavanjem broja motornih vozila navedeni problemi svakodnevno postaju sve veći. Stoga je prioritet brojnih prometnih organizacija i urbanih sredina pronaći načine kako reducirati broj vozila na prometnicama u svrhu smanjenja zagađenja okoliša, no da pritom zadrži dosegnuti nivo mobilnosti ljudi i robe. Jedan od načina postizanja ravnoteže između smanjivanja zagađenja okoliša i povećavanja mobilnosti ljudi i robe je Personal Rapid Transit (PRT). PRT sustav je atraktivni sustav javnog gradskog prijevoza koji omogućuje neprekidnu mobilnost ljudi i robe, od točke do točke, uz minimalno zagađenje. Dosad
je implementiran u nekoliko gradova i jednu zračnu luku te svojim djelovanjem potkrepljuju sve navedene prednosti u teoriji. Predloženi su
brojni PRT sustavi, ali većina ih, nažalost, nije implementirana, iako je on potpuno ekološki transportni sustav te kao takav ima ogroman potencijal za rješavanje trenutačnih problema u transportu. Istodobno je
i poprilično složen i sklon pogrešnom shvaćanju. PRT sustav još uvijek nije doživio svoje potpuno otkriće, a mogao bi promijeniti povijest transportnih sustava. Stoga je svrha rada ukazati na pozitivne strane PRT sustava. Navedeno je prikazano na konkretnom primjeru grada Masdara i
opisano kako su se uspjeli riješiti transportni problemi i onečišćenje okoliša uz primjenu PRT sustava. Cilj rada je prikazati PRT sustav kao nov i atraktivni oblik javnog gradskog prijevoza koji može zamijeniti klasične sustave javnog gradskog prijevoza i osobne automobile.
How to measure fatigue among
pilots?
Authors: Jerman Andrej , Meško Maja
Published: November 2018

Fatigue represents a major problem in aviation. Therefore, it is important to identify fatigue among pilots early enough before an incident or an accident occurs. The aim of our study has been to conduct a literature review on measurements of fatigue among pilots; to find out which measurements are used to recognize fatigue and what the results of conducted studies are with the focus on the usefulness of tests for measuring fatigue. The findings are based on meta-analysis. For the purpose of our study, we have used electronic databases Google Scholar, Emerald, MedLit and Academic Search Complete. The content analysis of the articles has been used to summarize and compare qualitative data. The results obtained show that tests for measuring fatigue can be divided into two groups, objective tests and subjective tests. Pilots’ subjective fatigue is mostly evaluated using Samn-Perelli fatigue scale, which is widely used in the aviation industry and it provides data for comparison. The contribution of our study is the widened understanding of fatigue measuring and usefulness of these measurements among pilots. The findings of our research are descriptive in nature. Further studies should be focused on deeper investigation of this topic and could include case studies of fatigue among pilots with qualitative data.
El proceso de reparto de tierras comunales en Michoacán y su documentación (1827-1915)
Authors: Venegas González Alicia
Published: November 2018

Acreedor de una mención honorífica en la categoría de ensayo del Segundo Premio de Archivística “Archivo General de la Nación - México” 2016, y adecuado a la modalidad de artículo, el presente trabajo aborda un recuento histórico del reparto de tierras comunales en Michoacán, durante el siglo XIX y principios del XX, así como la descripción del acervo documental generado, correspondiente a la serie “hijuelas”, que en su momento dio sustento a las gestiones de este proceso y en la actualidad son testimonio histórico que nutren investigaciones del tema en cuestión.
COMPARISON OF STATIONARY AND CYCLIC MODES OF INJECTOR-TYPE EXTRACTING COLUMN
Authors: Myasoyedenkov V. M. , Nagiyeva J. O.
Published: November 2018

Mathematical models were developed for two operational modes of the injector-type extraction column upon separation of the initial mixture. On the basis of a numerical experiment comparison of the cyclic operational mode with the stationary operational mode was carried out with respect to the extraction degree and the energy demand. It was confirmed that, as compared to the stationary operational mode, the cyclic operational mode provides a greater degree of extraction. The ratio of the extraction degrees in these operational modes of the extractor depending on the mass transfer criterion is of an extremal type. The maximum value of this ratio falls within the range from 1 to 4 and is equal to 1.5. It was also shown that the stationary operational mode of the extractor is more energy consuming than the cyclic one. The ratio of the energy demand for the stationary operational mode of the extractor to the energy demand in the cyclic operational mode depends on the extraction degree. This ratio grows from 1 to 5 within the interval of the extraction degree from 0.1 to 0.47.
ANALYTIC SOLUTION OF NONLINEAR LEYBENSON EQUATION IN THE THEORY OF FILTRATION
Authors: Аlexeev B. V.
Published: November 2018

Analytic solution of nonlinear Leybenson equation in the theory of filtration is obtained. Analytical solutions of the partial differential equations are presented in the explicit algebraic form. The integral surfaces in three dimensions are presented.
DETERMINATION OF LAMBDA-CYHALOTHRINE IN MICRO-INCAPSULATED INSECTICIDAL COMPOSITIONS
Authors: Nosikova L. A. , Kochetov A. N.
Published: November 2018

The determination of the title compound in the model microencapsulated insecticidal tools is considered, as well as the ability to conduct analysis in mixtures with other encapsulated means on the basis of a pyrethroid (cypermethrin, deltamethrin, tetramethrin, permethrin, phenothrin, transfluthrin) and phosphorus-containing derived insecticidal substances (chlorpyrifos). The conditions of direct analytical determination and the stage of sample preparation with the previously described methods are adapted. The content of lambda-cyhalothrin together with cypermethrin in microencapsulated compositions is determined by spectrophotometric method taking into account the absorption of trace contaminants - technical substances and building blocks of microcapsules (phospholipids). RP HPLC method shows the possibility of separate determination of lambda-cyhalothrin and several pyrethroids (except for cypermethrin), and chlorpyrifos, in the hypothetical compositions in a joint encapsulating order to obtain a highly active insecticide that enable overcoming the resistance of insects to a number of inactive substances.
OBTAINING ACTIVE COMPONENTS (Tа, Rа) of BIMETALLIC CATALYSTS ON γ-Al2O3 AND TiO2 MATRICES
Authors: Kulikova E. S. , Drobot D. V. , Chistyakov A. V. , Tsodikov M. V.
Published: November 2018

Tantalum methylate of general formula Ta2(OMe)10 was synthesized by electrochemical synthesis as a precursor for obtaining oxomethylate complexes of tantalum and rhenium. The complex is used to prepare catalysts in reactions of cross-condensation and reductive dehydration of alcohols. The catalysts are based on γ-Al2O3 and TiO2. Ultradisperse and nanosized TiO2 is obtained by the supercritical fluid technology. The sample is characterized by different methods (DTA, XRD, DSC). It is shown that annealing at 340°C allows obtaining anatase modification of TiO2 with a specific urface of 27.3 sq.m/g which can serve as a matrix for drawing active components of catalysts. It is shown that the Ta-Re/Al2O3 catalyst allows transforming ethanol and mixtures of ethanol with glycerin into aliphatic hydrocarbons C3-C11. A technological scheme for obtaining active components of the catalysts for cross-condensation and reductive dehydration of alcohols is suggested.