bluuebunny/crossref_metadata_2025 huggingface dataset:
Leveraging Intelligent-Field Data for Full Field Pressure Transient Analysis
Authors: Al-Wehaibi B.. , BinAkresh S.. , Issaka M.. , Al-Shamrani S..
Published: September 2015

The last several years have seen an explosion in the number new fields and increments being equipped with Intelligent Field technology, which includes remote monitoring and control of wells in real-time, as well as the acquisition of high frequency pressure and rate data from permanent downhole monitoring systems (PDHMS). This paper shows how this Intelligent Field data is being leveraged to obtain full-field reservoir characterization using both analytical and numerical pressure transient analysis methods. Utilizing data from a Saudi Aramco “intelligent” field, collected over a seven-month period, the paper employs pressure transient analysis to investigate the presence of reservoir boundaries and heterogeneities, and to obtain reservoir and well properties. This work reveals the importance of Intelligent Field data, how it can add value for the pressure trainset analysis, and how it is essential in the multiwell interpretation technique to yield accurate analysis. Major heterogeneity in the reservoir of this field was successfully detected and analyzed using the numerical multiwell interpretation technique, made available by Intelligent Field technology. The results are also compared with pressure transient analysis results from wireline gauge data collected through traditional buildup tests conducted on the same wells, to illustrate the distinct advantages of using Intelligent Field data over traditional wireline test data.
Seismic While-Drilling, Real-Data Reposition the Well in the Seismic Volume and Improve the Accuracy of the Depth Prognosis of the Target Events
Authors: El Tokhy M.. , Fahmy A.. , El marakeby H.. , Cox M.. , Okasha M.. , Khattab H. M. , El Hosary A..
Published: September 2015

Recording VSP data on wireline is a routine operation and its benefits and short comings are well understood. Recording a similar dataset while drilling allowing Real Time processing of the Seismic traces has several potential advantages in terms of time saving and decision making for the client without the need to pull the pipe out of the hole.

The Baker Hughes Seismic While tool was deployed in highly deviated well in Mediterranian Sea to acquire VSP traces from a Vertical Incidence VSP configuration (Source above receiver). The data is both recorded in memory and a trace extract transmitted to surface using the mud pulse system for real time QC and processing
LEAN Methodology in a Long Term Velocity String Campaign, a Step Forward in Snubbing Operations
Authors: Romero Javier , Janusz Norbert , Farei Ibrahim
Published: September 2015

LEAN concepts have been applied in a wide range of industrial areas to identify and eliminate the waste in every stage of different processes, currently improve efficiency and lower production costs has become popular among Oil and Gas senior-level management. Minimizing waste is the base on which LEAN concepts are built. A LEAN endeavor seeks to eliminate activities or processes that consume resources, add cost or require unproductive time without creating value. The concepts can be described as striving for excellence in operations in which each employee seeks to eliminate waste and participates in the smooth flow of value to the customer. As part of a complete new strategy to ensure permanent improvements within the whole operational environment Petroleum Development Oman (PDO) has applied LEAN on drilling and other corporate core areas. This paper presents a LEAN application to optimize the Snubbing Interventions in order to ensure a significant CAPEX and OPEX reduction in an extensive deliquification campaign for gas wells thru the implementation of high end Velocity String (VS) completions.

The projects involve the application of LEAN methodology from the early planning stages using in many cases re-engineering to the functional specifications, material selection and operational procedures. This re-engineering includes a deep review of every intervention activity, the application of new technologies and the analysis of major issues during previous snubbing interventions, followed by the measurement of the real operational times and deep technical brainstorming on every stage of the intervention process. All those factors have contributed with a significant amount of improvements along the intervention campaign.
Using Trees, Bagging, and Random Forests to Predict Rate of Penetration During Drilling
Authors: Hegde Chiranth , Wallace Scott , Gray Ken
Published: September 2015

Predicting rate of penetration (ROP) has always been of fundamental interest to the drilling industry. Early predictions can assist the engineer in changing parameters to reduce non-productive time (NPT) and achieve optimum ROP. This paper illustrates methods to predict the ROP in a computationally efficient manner using only data available at the surface. These methods can then be incorporated into real time drilling operations, first through a passive diagnostic tool, and then an integrated real-time control loop.

In this work, statistical learning techniques such as trees, bagged trees, and random forests (RF) are used to predict ROP. Trees provide easy interpretability and hence are favored over other non-linear techniques. However, accuracy is imperative in this procedure. Accuracy can be increased by using bootstrap aggregating (bagging) or Random Forests. These techniques are applied, using the statistical software computing package R and its numerous libraries. Statistical learning techniques have been applied to a data set which had nine predictors.

Applying trees to a data set yields great visualization of the data, but the lack of accuracy and can result in substantial overfitting. This shortcoming was rectified using bagging or RF methods to substantially increase accuracy. The results were promising in all cases and acceptable for real time predictions.

Scalability is another concern for real time operations. Computational efficiency of the methods were evaluated, and the best method was based on a combination of computational efficiency and accuracy. Potential time savings which would result from applying the model in real-time optimizations and demonstration of the power of machine learning techniques are included in this paper. Future improvements will be incorporated in real-time prediction during drilling.

State of the art statistical learning and machine learning techniques are applied to prediction of ROP, whereas previous prediction methods have not been based on real-time drilling data. The result is a computationally efficient model which can determine the right features for prediction at each step, while also incorporating engineering judgement and maintaining integrity of the statistical principles being employed. These methods can easily be extended to other drilling parameters such as MSE or Torque and Drag.
Integrated Operations on Offshore Formation Testing
Authors: Wang X.. , Xiao D.. , Dai Y.. , Lei G.. , Coskun S. B. , Fang Y..
Published: September 2015

Integrated operation (IO), the technologies used to enable distributed collaboration, was introduced to the petroleum industry many years ago, and is being successfully used for production optimization and real-time drilling operation. Previous operations prove it adds value to the industry.

The paper presents a workflow to develop and implement IO on offshore formation testing, which is formation pressure measurement and fluid sampling. The nature of offshore formation testing requires fast and effective decision-making during operation. And each decision is invaluable in the operation process. This paper is to give an answer of how to maximize the value of formation testing by IO.

Offshore formation testing brings together individuals from various disciplines, locations (offshore/onshore) and organizations (oil company/service supplier). The decision-making calls for contributions from all individuals. More importantly, the decision depends on real-time updated data which is measured and monitored from test. These features of formation testing coincide with the application of IO theory, which focuses on cooperation across disciplines using real-time information.

This paper describes the specializations of offshore formation testing operation, and lists the top benefits by the implementation of IO. Experiences are learned from other offshore-related disciplines in the petroleum industry. An optimal workflow to improve the decision-making process in formation testing is suggested. Furthermore, the responsibilities of individuals who are involved in formation testing are defined. At the end, we illustrate an example of the application of this model.
Multifaceted Simulation facilitate Drilling Performance analysis
Authors: Hani Ibrahim , Brahosky Daniel
Published: September 2015

This paper describes the procedures and steps implemented in the introduction and the instigation of a Drilling Performance Analysis Workflow. The task of drilling performance or offset analysis is paramount to the understanding and enactment of a successful drilling campaign, conversely in order to gain exceptional knowledge and profound understanding of problems root cause and the interdependency of the individual relationships a more comprehensive methodology has to be employed.

An Operator experienced several BHA failures in multiple and sequential runs that generated significant non productive time NPT within the multimillion dollar operation. Traditionally, the root cause analysis of a problem follows a certain path involving confirmation by the equipment manufacturing centre that the tools were prepared to specifications, while in parallel the drilling engineers scrutinize the environment where the tools were used and attempt to identify the culprit(s). The conclusion may combine the two findings, nonetheless our observation was that this is not generally the dominant outcome.

Hence, we embarked on developing a unique multifaceted workflow to tackle these inadequacies utilizing several 3-D and 4-D simulation and analysis tools. Individual workflows were established focusing on understanding the interrelated events and using 3D/ 4D modeling tools to relate events in the context of the environment and the interdependency of the BHA behavior and the milieu including exacerbating weather conditions. The software technology integrates data from various databases and organizes it in ways that aid visualization. Any particular areas of interest can be further examined thoroughly looking simultaneously at the geological references, telectric logging data, drilling parameters, and weather conditions all at a glance. The unique arrangement allows offset data from previous wells to be examined concurrently while the subject well is being drilled to assess the timeline of the issue or the recurring possibilities.

Utilizing the software to gather the information and assemble it in a manner that allow the engineers to spend more time analyzing the outcome rather than gathering and arranging data is a significant achievement on its own. The benefits extend to create a system of ownership with accountability for all involved personnel at the base who prepare the tools, at the office who plan and follow up the daily operations, and those who execute the plans at the wellsite.

The approch was proven to add significant value, with the next two well section drilled without any issues avoiding and improving the operator's time versus the planned authority for expenditure (AFE).
Saudi Aramco Real-Time Drilling Operation Activity Recognition & Analysis Engine
Authors: Khudiri Musab , Contreras William , Sanie Faisal , Jovin Tony , Hickin Gary , Kashif Muhammad
Published: September 2015

In recent years, the potential value of real-time drilling data has been well documented and applied across the globe within the Oil & Gas Industry. The information is traditionally used for timely and effective decision-making for drilling operations. Real-Time work processes has helped the industry by saving millions of dollars and mitigating the occurrence of critical hole problems. Drilling departments capitalize on the benefits of real-time data even in the planning stages of a well in order to prepare detailed drilling programs based on the history of any nearby wells. The easy access of real-time active and historical data assists the avoidance of incidents based on the witnessed reaction of the formation during the drilling process.

In order to do more with the data obtained, further analysis is required on the surface data to calculate the witnessed performance for certain activities on the rig site. The first step is to analyze surface data to prepare an operational recognition system. To automatically recognize drilling activities, an algorithm was developed that uses therealtime surface parameters data to calculate the current operation state, this is based on a 2-level activity classification hierarchy. The second step is then to use the results of the operational recognition system to determine key performance indictors based on the witnessed operations. It is therefore key that both calculated methods are as accurate as possible.

This paper will describe the business justification and the process formulated to generate meaningful KPI's for Saudi Aramco to allow for benchmarking and the sharing of best practices.
A System for Real-Time Drilling Performance Optimization and Automation Based on Statistical Learning Methods
Authors: Wallace Scott P. , Hegde Chiranth M. , Gray K. E.
Published: September 2015

This paper introduces a new system to optimize rate of penetration (ROP) while drilling by applying statistical learning methods for ROP prediction and providing real-time performance increases and closed-loop control. This paper establishes the viability of such a method, and then goes on to present a framework for phased development and integration into drilling rig operations. By developing such a system, the authors hope to provide a tool to the oil industry which can improve drilling efficiency, reduce non-productive time (NPT), and lower the cost of drilling.

The statistical model at the core of this system relies on complex machine learning techniques like random forests, neural networks and ensemble techniques to build a predictive performance model of the well from both real-time data and data from previously drilled offset wells. Each rock formation type is analyzed separately, allowing the model to anticipate ROP performance changes at formation boundaries. This model can then assess the controllable drilling parameters and determine whether there is an opportunity to increase ROP by adjusting these parameters to some other value.

The necessary real-time drilling data can be accessed on the WITS/WITSML protocol, and a framework for reading these data into our model in real-time was developed. By using parameter selection techniques, parameters which are significant in predicting ROP were identified. Consequently, an advanced statistical model was developed to process the available data into ROP predictions in real-time, and estimate changes on surface controllable parameters such that the optimum ROP could be reached. A three-phase testing and integration path was developed for taking this tool from concept to completion. The first phase is to apply the statistical model to data from wells which have already been drilled and determine the amount of time which could have been saved by optimizing ROP. Then the second phase is to integrate the system with real-time data acquisition and provide a passive indicator of the current well's optimization level with a red-yellow-green traffic light style indicator. The final stage is to implement closed-loop control, allowing the model to run in a fully automated state. Throughout this implementation, it was shown that there was substantial potential for ROP improvement by following the suggestions of this statistical model.

This concept is innovative as it relies only on data which can be measured in real-time on the rig floor, and does not require information about rock strength, formation drillability, or other downhole properties. This paper provides the path for integrating this new statistical drilling optimization model into drilling operations, and provides a blueprint to bring this concept from simulation to the field.
An Innovative Approach to Formation Evaluation with a Sourceless LWD Technology, A Case study from Partitioned Zone between Kuwait and Saudi Arabia
Authors: Al-Rubaiyea Jamal , Al-Bader Ahmad , Al-Houli Meshari , Al-Najim Abdul-aziz , Al-Duwaish Majed , Elsherif Ahmed
Published: September 2015

Logging While Drilling (LWD) tools with natural radioactive sources present risks to drilling and field development teams, due to the safety hazards inherent to the use of natural radioactive sources in the tools. If any natural radioactive source is left in the hole due to drilling conditions, a complex procedure is required to abandon the hole and sidetrack it.

Recently, a new sourceless LWD logging technique (NeoScope), which incorporates Pulsed Neutron Generators (PNG), was introduced to Wafra Joint Operations (JO).

The new technique provides multiple measurements (Resistivity / Density / Neutron / Sigma / Spectroscopy) from a tool located in a single 26 feet long collar. The PNG* uses electrical power generated from the Measurement-While Drilling (MWD) turbine to generate a large cloud of fast neutrons. These fast neutrons interact with the formation atoms to generate formation hydrogen index, Sigma, and spectroscopy data. In addition, the fast neutron interactions generate a secondary gamma ray cloud that can be used to measure formation density (similar to standard density measurement).

The first successful use of this tool in Wafra Joint Operations was in the first time for in South Fuwaris Field. The tool was run in a pilot hole with an inclination of 60°, cutting Ratawi Limestone and Ratawi Oolite reservoirs. The acquired data were excellent compared to conventional LWD data.

The proven success of this new technology provides risk mitigation / elimination for future operations. Extra care should be taken when using natural radioactive sources while drilling. The use of Sourceless LWD technology is a good risk elimination. Proper planning is required to ensure tool availability (only available for 8 ½” hole)
Integrated Subsurface and Drilling Work Environment Enables Geosteering to Maximize Wellbore Placement in Brown Field Development
Authors: Aillud Gary Stefan , David Richard Mohan
Published: September 2015

E&P Operators are facing challenges with the on-going development of brown fields and the increasing need for accurate wellbore placement and geosteering during infill drilling. This is driven by business plans that involve large in fill well drilling program. The planning and execution of these in fill wells will involve the drilling of highly deviated, horizontal and extended reach wells.

Good use has been made historically of the geosteering services provided by contractors in order to support drilling programs. This paper investigate the process of establishing an Integrated Geosteering Environment (IGE) that would enable efficient collaboration between reservoir geologist, petrophysicist, operational geologists, reservoir engineers and drillers engaged in field development. This environment makes use of a real time data to enable the drilling team to reduce risk and reservoir uncertainty while maximizing wellbore contact with the zone of interest. This will translate into reduced drilling time, better well placement and an increase in capital efficiency. The paper primarily focuses on the establishment of the IGE that will enable the development of workflows to optimize the placement of horizontal wellbore to achieve the business objective. The workflows cover predrill planning, drilling execution including 24/7 real time monitoring to steer the well, post well evaluation and update the reservoir model. This is enabled by real time data acquired while drilling along with modelling visualization tools.

Transforming from the current working environment into an Integrated Geosteering Environment combined with a real time Drilling Environment enables effective decision making and increased business agility towards achieving Operator business objectives, increasing oil recovery and sustaining the production capacity of brownfields.

There are several papers in the past addressing collaborative work environment or shared earth model. This paper discusses real time integrated workflow between sub-surface and drilling domains from a geosteering perspective.
Integrated Operations (IO) in Mining and Oil and Gas, What can we learn from each other?
Authors: Edwards A. R.
Published: September 2015

The objective of the paper is to compare and contrast the progress made in the implementation of IO in mining and oil and gas. IO or Digital Oilfield (DOF) has been a major performance improvement initiative in the oil and gas sector for over ten years with many examples now in place. IO for mining has seen a slower uptake with relatively few examples over the last five years. This paper will cover IO implementation examples from Mining in Australia and Chile and in Oil and Gas from Australia, Canada and Europe.

This paper will explore the similarities and difference in approach for the implementation of IO in mining and Oil and Gas. Specifically it will discuss:

Common drivers for IO in mining and oil and gas. Similarities between the application of IO Differences in the application of IO Single site versus a value chain approach. Remote control versus an operational support model. Characteristics of a successful implementation in both Mining and Oil and Gas. Key common lessons learned.

The results will be drawn from IO implementations in Iron Ore and Copper mining and from land based LNG and oil sands operations. The following items will be covered:

The use of remote collaboration, operations and engineering support in both mining and oil and gas. The use of remote control in land based operations in both mining and oil and gas. A comparison of the LNG value chain with the Iron Ore value chain. A comparison of the water cycle management in copper mining with the steam management in SAGD operations. Key conclusion on the similarities and difference of IO in mining and oil and gas.
Onset Latency of Motor Evoked Potentials in Motor Cortical Mapping with Neuronavigated Transcranial Magnetic Stimulation
Authors: Kallioniemi Elisa , Pitkänen Minna , Säisänen Laura , Julkunen Petro
Published: September 2015

Cortical motor mapping in pre-surgical applications can be performed using motor evoked potential (MEP) amplitudes evoked with neuronavigated transcranial magnetic stimulation. The MEP latency, which is a more stable parameter than the MEP amplitude, has not so far been utilized in motor mapping. The latency, however, may provide information about the stress in damaged motor pathways, e.g. compression by tumors, which cannot be observed from the MEP amplitudes. Thus, inclusion of this parameter could add valuable information to the presently used technique of MEP amplitude mapping. In this study, the functional cortical representations of first dorsal interosseous (FDI), abductor pollicis brevis (APB) and abductor digiti minimi (ADM) muscles were mapped in both hemispheres of ten healthy righthanded volunteers. The cortical muscle representations were evaluated by the area and centre of gravity (CoG) by using MEP amplitudes and latencies. As expected, the latency and amplitude CoGs were congruent and were located in the centre of the maps but in a few subjects, instead of a single centre, several loci with short latencies were observed. In conclusion, MEP latencies may be useful in distinguishing the cortical representation areas with the most direct pathways from those pathways with prolonged latencies. However, the potential of latency mapping to identify stressed motor tract connections at the subcortical level will need to be verified in future studies with patients.
An Inventory of Current Available Ultrasound Devices for Dental Use
Authors: Tina Le , Johan K.M. Aps
Published: September 2015

Objective : The first aim of the study was to make an inventory of the currently available ultrasound imaging devices on the market. The second aim was to identify portable ultrasound devices which could be used in general dental offices to image salivary glands, masticatory muscles and lymph nodes. Material and Methods : A list of ultrasound devices was collected from 11 international and American manufacturers using company websites and ultrasound retailer’s websites using the search engine Google®. Results : A total of 86 ultrasound machines from 11 different manufacturers were identified, of which only 14 devices are portable. Transducers are usually transferrable between devices of the same brand, and the non-portable machines have multiple transducer ports (three or four), while portable machines typically have only one or two ports. Portable machine weights range from 10 to 20 pounds, and often resemble large laptops, which are convenient to carry and take up minimal space in clinics. Conclusion : Some manufacturers provide portable and non-portable ultrasound devices. The first ones could be valuable in dental settings, as they can easily be moved around in the office.
Arachnoiditis Ossificans – A Rare Cause of Progressive Myelopathy
Authors: Steel Christopher J , Abrames Erik L , O’Brien William T
Published: September 2015

Arachnoiditis ossificans is a rare cause of chronic, progressive myelopathy. In contrast to the more common benign causes of meningeal calcification, arachnoiditis ossificans results in replacement of portions of the spinal arachnoid by bone as an end-stage complication of adhesive arachnoiditis. It is usually the sequela of prior trauma or interventional procedures. Prognosis and treatment options depend upon the location and degree of spinal stenosis with thoracic involvement being more common and more severe than lumbar spine involvement. The imaging findings on magnetic resonance imaging may be confusing; however, the findings of intraspinal ossification on computed tomography are characteristics and diagnostic. We present a classic case of arachnoiditis ossificans in an elderly man who presented with progressive myelopathy and a recent fall, along with a review of the literature. The imaging in this case not only identified the characteristic findings of arachnoiditis ossificans but also identified secondary findings of the underlying causative etiology.
Superconnectivity of networks modeled by the strong product of graphs
Authors: Casablanca R.M. , Cera M. , García-Vázquez P. , Valenzuela J.C.
Published: September 2015

Maximal connectivity and superconnectivity in a network are two important
features of its reliability. In this paper, using graph terminology, we
first give a lower bound for the vertex connectivity of the strong product
of two networks and then we prove that the resulting structure is more
reliable than its generators. Namely, sufficient conditions for a strong
product of two networks to be maximally connected and superconnected are
given
Estimating precision and accuracy of GC-TCD method for carbon dioxide, propane and carbon monoxide determination at different flow rate of carrier gas
Authors: Zuas Oman , Budiman Harry
Published: September 2015

Investigation on precision and accuracy of gas chromatography equipped with
thermal conductivity detector (GC-TCD) method for the measurement of CO2,
C3H8, and CO as pollutant models at different flow rate of helium (He)
carrier gas ranging from 17.50 to 36.25 ml/min were conducted. It was found
that percentage of relative standard deviation (%RSD) values for both
precision an accuracy show an overall gradual decrease as the carrier gas
flow rates increased up to 25 ml/min. After that, the %RSD was found to
increase with a further increase in the flow rate. These findings indicate
that the flow rate of 25 ml/min was found to be the most precise and accurate
level among all flow rates tested under experimental conditions of this
study. While the %RSD values obtained at all flow rate are given in details.
Consequently, our results suggest that the flow rate of carrier gas was a
determining parameter for varying the precision and accuracy of the GC-TCD
method. Owing to the fact that carrier gas act as a transporter of components
of the mixture in the form of vapor or gas through the column, setting of the
flow rate of carrier gas should in proper level achieve a precision and
accuracy of the GC-TCD method.
Paranoid schizophrenia versus schizoaffective disorder: Neuropsychological aspects
Authors: Leposavic Ljubica , Leposavic Ivana , Saula-Marojevic Biljana , Gavrilovic Predrag
Published: September 2015

Introduction. Neuropsychological aspects of paranoid schizophrenia have still
not been examined enough. These disorders are usually not studied separately,
but are included in the studies about schizophrenic patients with positive
symptoms. Despite the fact that schizophrenia represents a heterogeneous
group of mental disorders, usually it is not separated from schizoaffective
disorder in neuropsychological researches. Objective. The essence of this
research is to evaluate cognitive functioning of patients with paranoid
schizophrenia and schizoaffective disorder by applying neuropsychological
tests. Methods. The research included 91 subjects, right handed, from 30 to
53 years old, who were classified into three groups: inpatients with paranoid
schizophrenia in remission (n=31), inpatients with schizoaffective disorder
in remission (n=30) and healthy subjects (n=30). Results. Both groups of
patients showed poorer achievements than healthy subjects in most of the
applied tests. Patients with schizoaffective disorder showed global loss of
intellectual efficiency, executive dysfunction and compromised
visual-construction organization. Patients with paranoid schizophrenia
expressed partial loss of intellectual efficiency with verbal IQ and
executive functions preserved. Conclusion. In the remission phase, patients
with paranoid schizophrenia expressed cognitive disorders in moderate degree,
but when it comes to patients with schizoaffective disorder, more massive
cognitive deficits were registered.
Histological effects of enamel matrix derivative on exposed dental pulp
Authors: Popovic-Bajic Marijana , Danilovic Vesna , Prokic Branislav , Prokic Bogomir , Manojlovic Milica , Zivkovic Slavoljub
Published: September 2015

Introduction. Direct pulp capping procedure is a therapeutic application of a
drug on exposed tooth pulp in order to ensure the closure of the pulp
chamber and to allow the healing process to take place. Objective. The aim
of this study was to examine the histological effects of Emdogain? on
exposed tooth pulp of a Vietnamese pig (Sus scrofa verus). Methods. The
study comprised 20 teeth of a Vietnamese pig. After class V preparation on
the buccal surfaces of incisors, canines and first premolars, pulp was
exposed. In the experimental group, the perforations were capped with
Emdogain? (Straumann, Basel, Switzerland), while in the control group pulp
capping was performed with MTA? (Dentsply Tulsa Dental, Johnson City, TN,
USA). All cavities were restored with glass-ionomer cement (GC Fuji VIII, GC
Corporation, Tokyo, Japan). The observational period was 28 days, after
which the animal was sacrificed and histological preparations were made. A
light microscope was used to analyze dentin bridge formation, tissue
reorganization and inflammation, and the presence of bacteria in the pulp.
Results. The formation of dentin bridge was observed in the experimental and
control groups. Inflammation of the pulp was mild to moderate in both
groups. Angiogenesis and many odontoblast-like cells, responsible for dentin
bridge formation, were observed. Necrosis was not observed in any case, nor
were bacteria present in the pulp. Conclusion. Histological analysis
indicated a favorable therapeutic effect of Emdogain? Gel in direct pulp
capping of Vietnamese pigs. Pulp reaction was similar to that of MTA?.
The analysis of the risk factors in the arterial switch operation for treatment of D-transposition of the great arteries in one Pediatric Cardiac Center in Serbia
Authors: Stajevic-Popovic Mila , Sehic Igor , Prijic Sergej , Vukomanovic Vladislav , Kosutic Jovan
Published: September 2015

Introduction. The arterial ?switch? operation has been the operation of
choice for children born with Dtransposition of the great arteries (D-TGA)
for more than 30 years in countries with developed pediatric cardiac surgery
program. After two decades of successful treatment of these children with the
atrial ?switch? corrections (Mustard or Senning operative techniques), the
arterial ?switch? operation (ASO) had been introduced as a routine technique
in one pediatric cardiac center in Serbia. Objective. The aim of this study
was the analysis of the identified risk factors involved with the ASO in the
preoperative, operative and postoperative period and their impact on the
survival of the operated children. Methods. A retrospective nonrandomized
study of 52 operated patients with D-TGA by the ASO in the period between May
1, 2003 and December 31, 2011, divided into two groups. The data collection
consisted of preoperative, operative and postoperative factors during the
in-hospital stay and until the discharge from the hospital. Descriptive and
differential statistical methods were used for analysis. Results. Ten
individual risk factors were identified as significant for the immediate
survival of children operated with the ASO technique. Conclusion. The
arterial ?switch? surgical operative technique is a complex neonatal/young
infant procedure in which the preoperative status carried a significant risk
as well as the surgical technique itself. These results differ from the
results published throughout the world and are a representation of an
evolutionary process of one center in Serbia starting the ASO procedure.
Minimally invasive esophagectomy for cancer: Single center experience after 44 consecutive cases
Authors: Bjelovic Milos , Babic Tamara , Gunjic Dragan , Veselinovic Milan , Spica Bratislav
Published: September 2015

Introduction. At the Department of Minimally Invasive Upper Digestive Surgery
of the Hospital for Digestive Surgery in Belgrade, hybrid minimally invasive
esophagectomy (hMIE) has been a standard of care for patients with resectable
esophageal cancer since 2009. As a next and final step in the change
management, from January 2015 we utilized total minimally invasive
esophagectomy (tMIE) as a standard of care. Objective. The aim of the study
was to report initial experiences in hMIE (laparoscopic approach) for cancer
and analyze surgical technique, major morbidity and 30-day mortality.
Methods. A retrospective cohort study included 44 patients who underwent
elective hMIE for esophageal cancer at the Department for Minimally Invasive
Upper Digestive Surgery, Hospital for Digestive Surgery, Clinical Center of
Serbia in Belgrade from April 2009 to December 2014. Results. There were 16
(36%) middle thoracic esophagus tumors and 28 (64%) tumors of distal thoracic
esophagus. Mean duration of the operation was 319 minutes (approximately five
hours and 20 minutes). The average blood loss was 173.6 ml. A total of 12
(27%) of patients had postoperative complications and mean intensive care
unit stay was 2.8 days. Mean hospital stay after surgery was 16 days. The
average number of harvested lymph nodes during surgery was 31.9. The overall
30-day mortality rate within 30 days after surgery was 2%. Conclusion. As
long as MIE is an oncological equivalent to open esophagectomy (OE), better
relation between cost savings and potentially increased effectiveness will
make MIE the preferred approach in high-volume esophageal centers that are
experienced in minimally invasive procedures.
Severe blunt hepatic trauma in polytrauma patient: Management and outcome
Authors: Doklestic Krstina , Djukic Vladimir , Ivancevic Nenad , Gregoric Pavle , Loncar Zlatibor , Stefanovic Branislava , Jovanovic Dusan , Karamarkovic Aleksandar
Published: September 2015

Introduction. Despite the fact that treatment of liver injuries has
dramatically evolved, severe liver traumas in polytraumatic patients still
have a significant morbidity and mortality. Objective. The purpose of this
study was to determine the options for surgical management of severe liver
trauma as well as the outcome. Methods. In this retrospective study 70
polytraumatic patients with severe (American Association for the Surgery of
Trauma [AAST] grade III-V) blunt liver injuries were operated on at the
Clinic for Emergency Surgery. Results. Mean age of patients was 48.26?16.80
years; 82.8% of patients were male. Road traffic accident was the leading
cause of trauma, seen in 63 patients (90.0%). Primary repair was performed in
36 patients (51.4%), while damage control with perihepatic packing was done
in 34 (48.6%). Complications related to the liver occurred in 14 patients
(20.0%). Liver related mortality was 17.1%. Non-survivors had a significantly
higher AAST grade (p=0.0001), higher aspartate aminotransferase level
(p=0.01), lower hemoglobin level (p=0.0001), associated brain injury
(p=0.0001), perioperative complications (p=0.001) and higher transfusion
score (p=0.0001). The most common cause of mortality in the ?early period?
was uncontrolled bleeding, in the ?late period? mortality was caused by
sepsis and acute respiratory distress syndrome. Conclusion. Patients with
high-grade liver trauma who present with hemorrhagic shock and associated
severe injury should be managed operatively. Mortality from liver trauma is
high for patients with higher AAST grade of injury, associated brain injury
and massive transfusion score.
Toxoplasmosis and pregnancy: Reliability of internet sources of information
Authors: Bobic Branko , Stajner Tijana , Nikolic Aleksandra , Klun Ivana , Srbljanovic Jelena , Djurkovic-Djakovic Olgica
Published: September 2015

Introduction. Health education of women of childbearing age has been shown to
be an acceptable approach to the prevention of toxoplasmosis, the most
frequent congenitally transmitted parasitic infection. Objective. The aim of
this study was to evaluate the Internet as a source of health education on
toxoplasmosis in pregnancy. Methods. A group of 100 pregnant women examined
in the National Reference Laboratory for Toxoplasmosis was surveyed by a
questionnaire on the source of their information on toxoplasmosis. We also
analyzed information offered by websites in the Serbian and Croatian
languages through the Google search engine, using ?toxoplasmosis? as a
keyword. The 23 top websites were evaluated for comprehensiveness and
accuracy of information on the impact of toxoplasmosis on the course of
pregnancy, diagnosis and prevention. Results. Having knowledge on
toxoplasmosis was confirmed by 64 (64.0%) examined women, 40.6% (26/64) of
whom learned about toxoplasmosis through the Internet, 48.4% from physicians,
and 10.9% from friends. Increase in the degree of education was found to be
associated with the probability that pregnant women would be informed via the
Internet (RR=3.15, 95% CI=1.27-7.82, p=0.013). Analysis of four interactive
websites (allowing users to ask questions) showed that routes of infection
were the most common concern, particularly the risk presented by pet cats and
dogs, followed by the diagnosis of infection (who and when should be tested,
and how should the results be interpreted). Of 20 sites containing
educational articles, only seven were authorized and two listed sources.
Evaluation confirmed that information relevant to pregnant women was
significantly more accurate than comprehensive, but no site gave both
comprehensive and completely accurate information. Only four sites (20%) were
good sources of information for pregnant women. Conclusion. Internet has
proved itself as an important source of information. However, despite
numerous websites, only a few offer reliable information to the Serbian (or
Croat) speaking community, and none present complete and accurate information
relevant to pregnant women.
Inflammatory myofibroblastic tumours of the respiratory tract: A series of three cases with varying clinical presentations and treatment
Authors: Tegeltija Dragana , Lovrenski Aleksandra , Stojanovic Goran , Bijelovic Milorad , Jelicic Ivana , Eri Zivka
Published: September 2015

Introduction. Inflammatory myofibroblastic tumor in the respiratory system is
a rare and controversial disease. It is macroscopically well-circumscribed,
non-encapsulated, firm and usually a yellowish-white mass. Histologically it
is composed of the following spindled and inflammatory cells: lymphocytes,
plasma cells, and histiocytes, including Touton type multinucleated giant
cells. Case Outline. The series included a 49-year-old man with a tracheal
inflammatory myofibroblastic tumor who complained of hoarseness; a
42-year-old man who was coughing and had a blood-stained sputum, and
inflammatory myofibroblastic tumor was in the right main and intermediate
bronchus; and a 32-yearold man with chest pain and inflammatory
myofibroblastic tumor as a solitary peripheral nodule in the left lower lobe.
In all the cases, the tumor was resected bronchoscopically and surgically.
Conclusion. Inflammatory myofibroblastic tumor of the lung and the trachea is
rare. Complete resection, when possible, should be the choice of treatment.
After the complete removal, prognosis is generally excellent and recurrences
are rare.
Anaphylaxis on graft reperfusion during orthotopic liver transplantation: A case study
Authors: Andjelic Nada , Erdeljan Svetlana , Popovic Radmila , Bozic Teodora
Published: September 2015

Introduction. Hemodynamic instability is a common occurrence during liver
transplantation (LT). Hypotension and hemodynamic instability during graft
reperfusion are most commonly consequences of the postreperfusion syndrome
(PRS). Case Outline. In this report, we present a case of severe
cardiovascular collapse leading to cardiac arrest which occurred in the
course of graft reperfusion during LT. Persistent hypotension, non-responsive
to regular measures such as volume filling and the use of vasopressors,
yielded the question of whether other mechanisms were involved in causing it.
Diffuse redness of the face and body, swelling of the face, lips and tongue
with tongue prolapse, accompanied with severe cardiovascular collapse
indicated that it was an anaphylactic reaction. This caused a dilemma as to
what instigated the reaction. The trigger may have been the pharmacological
substance administered during the graft reperfusion, or the one administered
immediately prior to the reperfusion. The substances in question would most
likely be either the University of Wisconsin preservation solution (UW),
which was administered during the reperfusion, or Hepatect, which the patient
received immediately prior to reperfusion. Conclusion. The clinical syndrome
resulting from degranulation of mast cells and basophils in anaphylaxis is
very similar to the PRS in LT. Clinical features play the most important role
in establishing a timely diagnosis and early treatment of anaphylaxis. Swift
administration of epinephrine reduces the chances of a fatal outcome. Better
information on both donor and recipient can improve the efficiency of therapy
and prophylaxis for anaphylaxis.
Streptococcal necrotizing fasciitis with toxic shock syndrome and rapid fatal outcome
Authors: Kojic Miroslav , Mikic Dragan , Nozic Darko , Rakonjac Bojan
Published: September 2015

Introduction. Streptococcal necrotizing fasciitis (NF) is a serious soft
tissue infection with rapid progression of inflammatory process among
superficial or deep fascia, systemic host response to infection leading to
toxic shock syndrome (TSS), and multiple organ failure. Lethality is high.
Case Outline. A 46-year-old male without co-morbidities was admitted to the
Emergency Department with redness, swelling and pain on his right lower leg.
He became sick two day s ea rlier with m alaise, chills and shivering. On
admission he was hypotensive, anuric, with erythematous rash on his face,
neck and chest, with acute ren al failure and elevated creatine phosphokinase
level. During the next several hours, the changes on his right lower leg
rapidly spread to the whole leg, followed by skin destruction and subcutaneo
us bleeding, indicating NF. Aggressive antimicrobial, supportive and symptom
atic therapy was initiated immediately and on the same evening surgical
intervention was performed. Despite these measures, a rapid development of
severe TSS, with lethal outcome, occurred in less than 40 hours after the
admission. Stre ptococcus pyogenes (group A ?-hemolytic Streptococcus) was
isolated from the throat, skin and tissue obtained duri ng the surgery.
Conclusion. Necrotizing fasciitis is a very serious disease with unpre
dictable course. For that reason doctors must devote a great deal of a
ttention to early, i.e. timely diagnosis of this disease, whose treatment
with a multid isciplinary approach is very important.
Collisional emplacement history of the Naga-Andaman ophiolites and the position of the eastern Indian suture
Authors: Acharyya Subhrangsu K
Published: September 2015

Himalayan Journal of Sciences Vol.2(4) Special Issue 2004 p.87-8
Cenozoic tectonics of Central Asia: Basement control
Authors: Buslov Michael M
Published: September 2015

Himalayan Journal of Sciences Vol.2(4) Special Issue 2004 pp. 104-5
Cenozoic tectonics and geodynamic evolution of the Tien Shan mountain belt as response to India-Eurasia convergence
Authors: Buslov Michael M , De Grave Johan , Bataleva Elena A
Published: September 2015

Himalayan Journal of Sciences Vol.2(4) Special Issue 2004 pp. 106-7
Petrogenesis of basalts for Sangxiu Formation in the central segment from Tethyan Himalayas: Plume-lithosphere interaction
Authors: Dicheng Zhu , Guitang Pan , Xuanxue Mo , Zhongli Liao , Liquan Wang , Xinsheng Jiang , Zhidan Zhao
Published: September 2015

Himalayan Journal of Sciences Vol.2(4) Special Issue 2004 pp. 125-7
Younger hanging wall rocks along the Vaikrita Thrust of the High Himalaya: A model based on inversion tectonics
Authors: Dubey Ashok K , Bhakuni Surendra S
Published: September 2015

Himalayan Journal of Sciences Vol.2(4) Special Issue 2004 pp. 129
An Overview of Particulate Matter Measurement Instruments
Authors: Amaral Simone , De Carvalho João , Costa Maria , Pinheiro Cleverson
Published: September 2015

This review article presents an overview of instruments available on the market for measurement of particulate matter. The main instruments and methods of measuring concentration (gravimetric, optical, and microbalance) and size distribution Scanning Mobility Particle Sizer (SMPS), Electrical Low Pressure Impactor (ELPI), and others were described and compared. The aim of this work was to help researchers choose the most suitable equipment to measure particulate matter. When choosing a measuring instrument, a researcher must clearly define the purpose of the study and determine whether it meets the main specifications of the equipment. ELPI and SMPS are the suitable devices for measuring fine particles; the ELPI works in real time. In health-related studies, a Diffusion Charger is the instrument that best characterizes the surface of ultrafine particles. Several methods and different particle measuring instruments should be used to confirm the values obtained during sampling.
Advances in Environmental Psychology
Authors: Nasar Jack
Published: September 2015

When Plenum stopped publishing its edited series—Human Behavior and Environment and Advances in Environment, Behavior and Design—the field of environmental psychology suffered a loss. Scholars could go to one of the edited Plenum books to find state-of-the-art reviews on existing and emerging areas of research. [...]