bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping the Hydrocarbon Envelope From Inside a Wellbore—Reducing Uncertainty During Infill Drilling
Authors: Mnich Cheryl , Bisain Amarjit , Perna Ferdinando , Mearns Leanne , Saputra Eky , Anderson Callum , Dupuis Christophe
Published: September 2015

In 2014 ConocoPhillips (U.K) Ltd. drilled a third development well, a horizontal infill, in the Brodgar gas condensate field (central North Sea) to target a low relief structure 6,000 ft west of the existing production wells. A new deep resistivity tool was successfully used in this well to aid geosteering and mapping of the hydrocarbon envelope.

A pilot well was originally proposed to reduce uncertainty around the hydrocarbon-water contact (HWC) and the top structure depth at the target location. However during data acquisition planning, extensive simulations of the response of the deep directional resistivity (DDR) logging-while-drilling (LWD) tool were carried out to evaluate its capability to reduce these uncertainties. The simulations gave confidence in the ability of the DDR tool to: (1) detect the reservoir 50 ft true vertical depth (TVD) away before wellbore arrives at top reservoir; and (2) effectively map the top and base of the entire reservoir zone. The decision was made to drop the pilot well and apply this new technology to mitigate the risks and meet the well plan and production objectives. This decision was supported by detailed reservoir simulation work and uncertainty modelling.

The tool response showed the range of hydrocarbon column height upon landing at the initial target location to be between 70 and 110 ft (mid case predrill simulations predicted a column of 104 ft). Due to mechanical issues, this initial wellbore had to be abandoned and sidetracked at the 13 3/8-in shoe. As the sidetrack was a twin of the abandoned hole, the DDR LWD tool was not required for landing the sidetrack but was used for geosteering the horizontal section. The tool provided a real-time resistivity profile that could be interpreted up to 80 ft above and below the wellbore resulting in an accurate “map” of the hydrocarbon envelope. The tool has helped to significantly reduce uncertainty on top structure depth and on water encroachment behaviour, leading to re-interpretation of the seismic, static, and dynamic models.

For ConocoPhillips (U.K) Ltd. this case study has demonstrated the value of applying new technology to reduce subsurface uncertainties and eliminate unnecessary well cost.
Digital Oil Field Powered with New Empirical Equations for Oil Rate Prediction
Authors: Espinoza R..
Published: September 2015

Empirical equations have always been used to fit and later predict oil rate production. The most common and widely use empirical equation are those we use during production decline analysis. With decline analysis equations we are able to predict in most cases production decline as a consequence of reservoir pressure decline. However, these equations will not perform as desired when a sudden reduction on the oil rate of a well has occurred as a consequence of changes on the well head parameters such as a change of the production choke or the gas oil ratio (GOR). These unexpected changes of the oil rate are not able to be predicted with most common used decline analysis equations and generally speaking with deterministic equation sets.

In this paper, a new empirical equation is described to allow the calculation of oil rate from a given well when only information of choke size and well head pressure is available. Calculated production from this equation shows outstanding result in terms of precision when compared with other equations available in the literature like Gilbert, W.E. (1954) and Ros, N.C.J. (1961). In addition, this equation can serve as a great operational surveillance tool when incorporated into a centralized production system and database. Finally, the methodology is described in a way that the reader can apply and adjust the equation to be used in oil fields with naturally flowing wells and stable water cuts.
Advanced Intelligent Completion Solution for Extended Reach Wells
Authors: Basak Debasmita , Gurses Sule
Published: September 2015

Extended Reach Drilling (ERD) wells can be extremely long and technically challenging from drilling through completions, clean up, stimulation and production optimization. This paper will focus on the key challenges associated with ERD well completion, real-time clean up, production monitoring and optimization and will present an advanced intelligent solution enabled by new technologies to handle these complex challenges.

As the fields become more mature, there is an increasing requirement for real time flow profile understanding and interventions to correct unwanted flow profile anomalies such as water production, gas breakthrough, etc. to have better production and reservoir management. By combining real-time data monitoring and active control with optimal zonal isolation along the wellbore has been proven to be one of the most efficient and effective completion strategies in the industry for the abovementioned requirements. The operator can proactively manage production, eliminate or reduce interventions and associated production downtime, well costs and risks. However, getting the invention less permanent intelligent completions to the Total Depth (TD) of ERD wells is one of the major challenges and hence very long horizontal ERD wells are typically completed partially leaving out stretches of reservoir section unmonitored and uncontrolled. Also, conventional intelligent completions have clear limitations on number of flow control valves and sensors that can be deployed in a well, mainly limited by the maximum number of control lines, which can be deployed with the completion. The limitation comes from the feedthrough port limitation of critical completion tools such as tubing hanger, production packer etc. and also from the completion deployment challenges faced with increasing number of control lines. This limits the ability to have an optimal segmentation along the wellbore in many cases.

Another important challenge that our industry faces is in effectively using real-time monitoring data to make informed decisions and take required actions efficiently. Traditionally the whole process of data gathering from down hole tools to decision making and taking reasonable action is long ranging from months to years and requires multi-disciplinary expertise. As a result the well controllability, reservoir management and hence production optimization are compromised due to technology solutions limitation.

New all electrical solution with reliable downhole wet connects and integrated answer product software for data management and analysis of real-time data presented here is a key intelligent end to end solution. This paper gives details of this new generation technology solution that enables above mentioned challenges.
ICS and IT: Managing Cyber Security Across the Enterprise
Authors: Effendi Asif , Davis Robert
Published: September 2015

Industrial Control Systems (ICS) were originally built on proprietary technology and primarily focused on “up-time” and “safety”. Being isolated from the business environment they were independent islands of networked devices. However, ongoing advancements in business technology, brought with it new possibilities, such as the ability to access data and systems located inside of the previously isolated ICS environments. At this point many Industrial Control Systems (ICS) moved from proprietary technologies, to using the same protocols as business IT systems. This paradigm shift has led to an evolving convergence of business and process control networks, which has generated the effect of increased efficiency and visibility to field operations, but also brought with it new cyber security challenges.

Modern technologies contain well known cyber exploits and vulnerabilities which are now inherited in the ICS environment. As a result, ICS environments find themselves directly in the crosshairs of cyber attackers. Effective management of these cyber security challenges and exposures in the ICS environment has emerged as an important and dynamic element in the operational safety, security, and reliability of the infrastructure in the oil & gas industry.

Many of the principles for protection and controls used in the enterprise environment should now be adapted to fit the ICS environment. However, requirements within the ICS differ significantly from the enterprise and should be considered.

This paper will provide an oil and gas industry insight into cyber security programs and countermeasures, and will explore the similarities and differences between IT and ICS protection and risk management.
Converting ESP Real-Time Data to Flow Rate and Reservoir Information for a Remote Oil Well
Authors: Camilleri L.. , El Gindy M.. , Rusakov A.. , Adoghe S..
Published: September 2015

Flow-rate testing is the most fundamental and essential form of reservoir surveillance and is typically performed on a monthly basis using a test separator. This case study reviews the results from modelling a well located in a jungle for which poor testing quality precluded inflow analysis. The main causes were logistical difficulties, large flow transients, and phase segregation in the flowline between the wellhead and test separator.

A virtual flowmetering technique was investigated to determine a trend of reservoir pressure and skin and identify production optimisation opportunities. The algorithms used real-time data from permanent downhole gauges and electric submersible pump (ESP) surface controllers, which provided the necessary measurement frequency, resolution, and repeatability to capture well performance transients and provide a full production history. The liquid rate calculation used the principle that the power absorbed by the pump is equal to that generated by the motor. Water cut was calculated by modelling the production tubing pressure drop with a multiphase correlation.

Virtual flowmetering is demonstrated to provide a credible alternative where test separators and multiphase meters cannot be deployed owing to logistical difficulties such as in swampy terrain or on unmanned platforms and subsea. Furthermore, the high frequency, resolution, and repeatability of this particular flowmetering technique are greater than those obtained with traditional monthly, or even weekly, test separator data. This case study illustrates how these three attributes enhance nodal analysis, pressure transient analysis (PTA), and superposition, which enabled monitoring the well's reservoir pressure and well interference without the need to conduct pressure buildups.

Additional value comes from extending the application of this virtual flowmetering technique to wells that do not have testing difficulties, especially those that are under producing and require detailed diagnostics (e.g., PTA). The technique is also well suited to application in true real time because it is analytical, valid across the full pump range, and able to capture transients without requiring an iterative process. Is real-time flow rate just around the corner?
Enhance the Drilling & Tripping Performance on Automated Rigs with fully automated performance measurement
Authors: El Afifi Sameh , Albassam Bassam , Fahmy Fadi Atef
Published: September 2015

This paper describes the development and implementation of a unique new capability to automatically measure the performance of drilling crews and Invisible Lost Time; the supporting technology service makes it possible to carry out detailed comparisons of the performance of crews across a large number of installations. This technology service uses rig sensor data to automatically generate an objective description of the drilling process using the patented “Automated Operations Recognition System” without the need of additional personnel or equipment on the rig site.

This simply will help improving rig performance of drilling and tripping operations and allow benchmarking and comparison between different rigs and different crews etc.

The service is used to; Analyze the drilling process at a high level of quality and detail which complements traditional morning reporting. The patented “Automatized Operations Recognition System” has the potential to significantly reduce total well time by setting standardized and objective benchmarks in order to identify non-productive or “Invisible Lost Time”, otherwise known as “ILT” and to maintain an increase in performance.Uses a well-defined set of Key Performance Indicators (KPI) to measure drilling performance accurately in order to make Invisible Lost Time visible.Compare actual performance with predefined practices, and then maintain performance-optimized procedures once they are in place.Optimize an organization’s performance through benchmarking and trend analysis using Automated Drilling Performance Measurement system.

Among many of the examples presented in the paper will be one on the variation in the tripping slip to slip connection time and drilling weight to weight time of 4 wells on 3 rigs.

In addition, the variation among different drilling crews on each rig which showed huge differences when comparing similar operations. The paper will also present the potential savings after implementing this initiative.
Collaborative Working in Shell - Value Achieved, More to Follow
Authors: van den Berg Frans G. , McCallum G. A. , Wallace Stewart
Published: September 2015

Collaborative Work Environments (CWEs) have been implemented in the majority of Shell’s assets. The large scale deployment was achieved through a structured programme, taking assets and projects through a standard CWE design, implementation and embedding approach.

This paper provides an overview of the progress of Shell’s CWE programme. It shows its reach, the value achieved, the learnings and the response to the current low cost environment. It also looks forward to further opportunities for collaborative working in wider business areas in an oil and gas company.
Enhanced Kick Detection with Low-Cost Rig Sensors Through Automated Pattern Recognition and Real-Time Sensor Calibration
Authors: Pournazari Parham , Ashok Pradeepkumar , van Oort Eric , Unrau Sean , Lai Stephen
Published: September 2015

In recent years, the drilling industry has been exploring the use of sophisticated downhole sensors and more elaborate surface sensors to improve prediction and detection of trouble events such as kicks, fracture breathing and lost circulation. The use of such sensors, however, comes at a considerable additional cost and is often difficult to justify on low-cost land-based wells. On the other hand, the conventional suite of low-cost surface sensors often drift out of calibration and, without manual intervention, can provide bad data that may lead to missed or false alarms. It would be highly desirable if the conventional sensors could still be used but with improved robustness and precision for event detection. This paper reviews existing event detection methods and their shortcomings, and proposes a new method that not only addresses these shortcomings, but also improves the quality of the sensor data gathered.

This paper presents a pattern-recognition system that allows for fast analysis of sensor patterns to identify events, and a real-time sensor calibration methodology that uses a combination of a physics- based model and machine-learning techniques to improve the quality and usability of rig sensor data. Focus is on gains/kick events in particular. The calibration algorithm analyzes the quality of sensors in a mud circulation system and calibrates these sensors to yield meaningful data. This leads to a much higher accuracy in the sensed data, e.g. by mitigating flow sensor drift. The presented event detection system can then more reliably detect a kick, lost circulation or a fracture breathing event with reduced frequency of false/missed alarms.

The proposed method has been tested and implemented on actual mud circulation sensor data from the field. Using the analyzed data we demonstrate how real-time calibration can high-grade the data from a simple flow paddle sensor into much more accurate flow rate readings. We also show how sensor calibration allows for increased confidence in the values of other sensors as well, such as the pump stroke counter readings. Ultimately, the method presented in this paper allows one to extract more meaningful information from inexpensive surface sensors and make drilling trouble event predictions that are much more accurate than currently available industry methods.
Fusion of Real Time Data Transmission and Visualization to Optimize Exploration Well Testing Operations
Authors: Miyajan Ramzi , Khudiri Musab , Wuhaimed Ali , Gill Harmohan , Nahdi AbdulHakim , Kashif Muhammad , Meraj Hamood
Published: September 2015

One of the critical operations during the exploration phase is well testing required determining fluid type, flow rate, and the sustainability of the production. With the right planning, technology and implementation, well testing can ensure reservoir quality and production such as, permeability, initial reservoir pressure, hydraulic fracture parameters, near wellbore formation damage, geometry of the reservoir, and reserve quantities.

Exploration Well Testing Operations require a complex integration of various services including surface well testing, artificial lift via coiled tubing, downhole data transmission and on-site operational activities. The increase in exploration activities involves various service companies’ proprietary data acquisition systems that introduce a challenge for decision makers due to segmented data and information. This calls for establishing an integrated unified viewer combining the operational data for engineers to enable real-time data supervision, technical support and decision making from the headquarters to well-site locations reducing operational risks and optimize required cost.

This paper highlights the progress of the real time data transmission interface to support highly active exploration well testing operations in Saudi Aramco.
Real Time Well Testing: A Game Changer – Experience and Lessons Learned Over 100 Well Tests Performed In the North Sea
Authors: Hollaender F.. , Shumakov Y.. , Sarac S.. , Theuveny B..
Published: September 2015

Obtaining accurate and representative well testing information is critical for the proper characterization of a reservoir, with confidence and quality of data being of paramount importance during a well test. Over the last few years, well testing has become real-time enabled, following in the footsteps of drilling, wireline logging and production operations. However, making a better well test is not just about enabling the technology. It is also about ensuring that the right people have access to the right data and that adequate decision-making processes are available. This requires that reservoir engineers are trained in operational aspects, rig crew are able to communicate and implement remotely taken decisions, and the “end-users” of the well test are fully engaged in the real time monitoring, analysis and execution processes.

The real-time well testing approach presented in this paper is the result of the evolution from basic real-time data transmission to a reliable real-time data delivery and analysis infrastructure that has taken place over the last five years. Throughout the 100 real-time well tests completed in the North Sea, the workflows used to process and analyze the data have evolved significantly, enabling the processed information to be leveraged for decision-making and to update test programs. Recently developed downhole tools and components controlled remotely via a wireless acoustic telemetry system, and providing real-time access to downhole pressure data, have enhanced and broadened the applicable workflows and capabilities.

This paper also presents the evolution of remote connectivity systems and the exploitation of their technical capabilities to their full potential so that off-site experts can witness, collaborate and support operations on a 24/7 basis. By these means, the right expertise can be utilized regardless of location. In addition, we present several case studies where real time data delivery, remote monitoring and support were crucial for continuous quality assurance and for successful pressure transient analysis which led to better reservoir characterization. The change in the mindset of management in both operating companies and service suppliers is essential to ensure that the power of real-time enabled well testing is fully leveraged.
Collaborative Work Environment Implementation: A Step Change in Deepwater Operation Integration
Authors: Udofia Emmanuel , Tulalian Robert , Akintunde Atanda , Martins Amos
Published: September 2015

Collaborative Working Environment (CWE) is an enhanced operation integration concept through the use of seamless connection of hardware and software tools, defined business processes, people and tele-presence facility. Additionally Collaborative Working Environment is any form (physical or virtual) in which teams can come together to discuss, in a bid to reach a common decision. It is expected, the solutions from this implementation will provide a common data-set for faster decision making through collaboration between functions or teams regardless of location.

The went operational in Shell Nigeria Offshore assets Operations Collaboration Centre took place in December 2014 and this paper aims to describe the benefits in the project implementation and process embedment. The discussion will equally highlight the change brought about in Bonga asset operation integration following the delivery of the collaborative working environment in the offshore asset with Bonga field being the first deepwater field sub-Sahara Africa. Key indicators in observed benefits include; impact on safety, team-integration, speed in quality decision making and significant reduction in cost related to field logistics. In extension, overall impact on the business objective and work culture has been reviewed. It has been established that with this project implementation exceptional benefit has been achieved in team collaboration and quality decision making.

It is acknowledged that this way of working has delivered short term benefits but the objective is to sustain and improve on the day-to-day operational benefits. The recommendations from this paper could assist in similar project implementation and embedment efforts elsewhere in the oil and gas industry.
Analysis of Pharyngeal Airway Using Lateral Cephalogram vs CBCT Images: A Cross-sectional Retrospective Study
Authors: Bronoosh Pegah , Khojastepour Leila
Published: September 2015

Background : As the basic biological relationship of form and function, changes in the normal pattern of nasopharyngeal space can profoundly affect the development of the craniofacial growth. The lateral cephalogram, part of the patient’s normal records for orthodontic treatment, may show some of these changes either at the initial examination or later during treatment. The validity of the information the lateral cephalogram may present, have been questioned previously. The aim of this study was to assess correlation between the area and the volume measurements of pharyngeal airway size in a lateral cephalogram and a 3-dimensional (3D) cone-beam computed tomography (CBCT) scan in adolescent subjects. Materials and Methods : CBCT scan and a lateral cephalogram of 35 subjects which were taken within 1 week were included in this study. Airway area of the region of interest from the lateral cephalogram and airway volume over the same of region of interest from the CBCT scan were assessed for all patients. The correlation between the area and the volume measurements were evaluated statistically by Pearson’s correlation coefficient test. Mann Whitney U Test was used for comparing the area and the volume measurements in different sex. Results : Strong correlation was found between lateral cephalogram and CBCT measurements of pharyngeal airway. (r=0.831). Conclusion : Pharyngeal airway area on a lateral cephalogram is correlated strongly with volumetric data on CBCT images. Henceforth the use of CBCT images for volume measurements in orthodontic patients can aid in the better evaluation of airways and acted as a diagnostic instrument in this area.
Evaluation of the Root and Canal Morphology of Maxillary Permanent Molars and the Incidence of the Second Mesiobuccal Root Canal in Greek Population Using Cone-beam Computed Tomography
Authors: Nikoloudaki Georgia E. , Kontogiannis Taxiarchis G. , Kerezoudis Nikolaos P.
Published: September 2015

Objectives: Cone-Beam Computed Tomography is an alternative imaging technique which has been recently introduced in the field of Oral & Maxillofacial Radiology. It has rapidly gained great popularity among clinicians due to its ability to detect lesions and defects of the orofacial region and provide three-dimensional information about them. In the field of Endodontics, CBCT can be a useful tool to reveal tooth morphology irregularities, additional root canals and vertical root fractures. The objective of this study is to evaluate the root and root canal morphology of the maxillary permanent molars in Greek population using Cone-Beam Computed Tomography.Materials and Methods:273 cone-beam computed tomography (CBCT) images were examined. The number of roots and root canals of the first and second maxillary molars were evaluated. Root canal configuration was classified according to Weine’s classification by two independent examiners and statistical analysis was performed.Results:A total of 812 molars (410 first and 402 second ones) were evaluated. The vast majority of both first and second molars had three roots (89.26% and 85.07%, respectively). Most first molars had four canals, while most second molars had three. In the mesiobuccal roots, one foramen was recorded in 80.91% of all teeth. Other rare morphologic variations were also found, such as fusion of a maxillary second molar with a supernumerary tooth.Conclusion:Within the limitations of this study, it can be concluded that more attention should be given to the detection of additional canals during root canal treatment in maxillary permanent molars. Towards this effort, CBCT can provide the clinician with supplemental information about the different root canal configurations for successful Root Canal Treatment.
Effect of Septal Deviation, Concha Bullosa and Haller’s Cell on Maxillary Sinus’s Inferior Pneumatization; a Retrospective Study
Authors: Göçmen Gökhan , Borahan Mehmet Oğuz , Aktop Sertac , Dumlu Asım , Pekiner Filiz Namdar , Göker Kamil
Published: September 2015

Purpose: Maxillary sinus’s inferior pneumatization is a physiological process, which increase with time and accelerates following extraction. The aim of this study was to determine the prevalence of nasal septal deviation (NSD), concha bullosa (CB), and Haller’s cells (HC) and to examine the correlation of maxillary sinus inferior pneumatization (MSIP) with these anatomical variations. Material and Methods : 300 (150 m, 150 f) CBCT scans taken at the Marmara University School of Dentistry from 2011 to 2014 were retrospectively reviewed for the presence of CB, NSD, HC and MSIP. The correlation between pneumatization to the anatomic variants was then compared. Data were analyzed with a Chi-square test. Results : Of the 300 CBCT scans, 44.3% have CB, 37.3% NSD, 19.3% HC and 27.7% MSIP. There was no statistical significancewhen comparing the relationship of patients with CB, NSD, HC and pneumatization. Conclusion : NSD, CB and HC do not have a definite role on sinus’s inferior pneumatization. Further studies should be conducted including potential factors related pneumatization with more sample size for further correlation with NSD, CB,HC.
Relationship Between the Thickness of Cortical Bone at Maxillary
Mid-palatal Area and Facial Height Using CBCT
Authors: Johari Masume , Kaviani Farzaneh , Saeedi Arman
Published: September 2015

Introduction : Orthodontic mini-implants have been incorporated into orthodontic treatment modalities. Adequate bone at mini-implant placement site can influence the success or failure of anchorage. The present study was to determine the thickness of cortical bone in the maxillary mid-palatal area at predetermined points for the placement of orthodontic mini-implants using Cone Beam CT technique in order to evaluate the relationship of these values with the facial height. Materials and Methods : A total of 161 patients, consisting of 63 males (39.13%) and 98 females (60.87%), were evaluated in the present study; 38% of the subjects had normal facial height, 29% had short face and 33% had long face. In order to determine which patient belongs to which facial height category, i.e. normal, long or short, two angular and linear evaluations were used: the angle between S-N and Go-Me lines and the S-Go/N-Me ratio. Twenty points were evaluated in all the samples. First the incisive foramen was located. The paracoronal cross-sections were prepared at distances of 4, 8, 16 and 24 mm from the distal wall of the incisive foramen and on each cross-section the mid-sagittal and para-sagittal areas were determined bilaterally at 3- and 6-mm distances (a total of 5 points). The thicknesses of the cortical plate of bone were determined at the predetermined points. Results : There was a significant relationship between the mean cortical bone thickness and facial height (p<0.01), with significantly less thickness in long faces compared to short faces. However, the thickness of cortical bone in normal faces was similar to that in long and short faces. Separate evaluation of the points showed that at point a16 subjects with short faces had thicker cortical bone compared to subjects with long and normal faces. At point b8 in long faces, the thickness of the cortical bone was significantly less than that in short and normal faces. At point d8, the thickness of the cortical bone in subjects with short faces was significantly higher than that in subjects with long faces. Conclusion : At the point a16 the cortical bone thickness in short faces was significantly higher than normal and long faces. The lower thickness of the cortical bone in the palatal area at points b8 and d8 in subjects with long faces might indicate a lower anchorage value of these points in these subjects.
Evaluation of a Mathematical Model for Digital Image Enhancement
Authors: Geha Hassem , Nasseh Ibrahim , Noujeim Marcel
Published: September 2015

Objective: The purpose of this study is to compare the detected number of holes on a stepwedge on images resulting from the application of the 5th degree polynomial model compared to the images resulting from the application of linear enhancement.Material and Methods:A 10-step aluminum step wedge with holes randomly drilled on each step was exposed with three different kVp and five exposure times per kVp on a Schick33®sensor. The images were enhanced by brightness/contrast adjustment, histogram equalization and with the 5th degree polynomial model and compared to the original non-enhanced images by six observers in two separate readings.Results:There was no significant difference between the readers and between the first and second reading. There was a significant three-factor interaction among Method, Exposure time, and kVp in detecting holes. The overall pattern was: “Poly” results in the highest counts, “Original” in the lowest counts, with “B/C” and “Equalized” intermediate.Conclusion:The 5th degree polynomial model showed more holes when compared to the other modalities.
Assessment of the Horizontal and Vertical Position of Mental Foramen in Indian Population in Terms of Age and Sex in Dentate Subjects by Pano-ramic Radiographs: A Retrospective Study with Review of Literature
Authors: Parnami Priyanka , Gupta Deepak , Arora Vishal , Bhalla Saurabh , Kumar Adarsh , Malik Rashi
Published: September 2015

Objective : To familiarize new criteria to access vertical position of mental foramen in panoramic radiographs. Furthermore, to determine and compare the position and symmetry of mental foramen in horizontal as well as in vertical plane in Indian population and to compare the results with those reported for other populations in the literature. Further gender differences in mental foramen position were also accessed to comment on the reliability of panoramic radiographs for sex determination. Methods and Material : Six hundred digital panoramic radiographs were selected and studied regarding the location and symmetry of mental foramen. They were also compared with the other studies in the literature. The method employed is similar to that described by Al Jasser and Nwoku for horizontal position and Fishal et al. for vertical position of mental foramen. Certain modifications were carried out in Fishal’s criteria for vertical position assessment. Results : The commonest position of the mental foramen in horizontal plane was in line with the longitudinal axis of the second premolar (61.0%) while in vertical plane it was found to be located inferior to the apex of second premolar (72.2%). Conclusion : Mental foramen exists in different locations and possesses many variations. Hence, Individual, gender, age, race and assessing technique largely influence these variations. It suggests that the clinicians should carefully identify these anatomical landmarks, by analyzing all influencing factors, prior to their diagnostic or the other dental, surgical and implant operation.
Digital DICOM in Dentistry
Authors: Burgess Jeff
Published: September 2015

Similar to Medicine, digital communication, information processing, and x-ray imaging have changed the face of dentistry. The incorporation of digital systems into medical and dental practice has necessitated development of a standard that allows reliable transmission of information between the devices taking the images, devices storing the images, and devices displaying the images. This standard is termed as DICOM. The following article briefly reviews how DICOM came about, how dentistry is involved, the various elements that are part of the DICOM system, and how DICOM is currently used in dentistry.
Pontine Infarct Presenting with Atypical Dental Pain: A Case Report
Authors: Goel Rajat , Kumar Sanjeev , Panwar Ajay , Singh Abhishek B
Published: September 2015

Orofacial pain’ most commonly occurs due to dental causes like caries, gingivitis or periodontitis. Other common causes of ‘orofacial pain’ are sinusitis, temporomandibular joint(TMJ) dysfunction, otitis externa, tension headache and migraine. In some patients, the etiology of ‘orofacial pain’ remains undetected despite optimal evaluation. A few patients in the practice of clinical dentistry presents with dental pain without any identifiable dental etiology. Such patients are classified under the category of ‘atypical odontalgia’. ‘Atypical odontalgia’ is reported to be prevalent in 2.1% of the individuals. ‘Atypical orofacial pain’ and ‘atypical odontalgia’ can result from the neurological diseases like multiple sclerosis, trigeminal neuralgia and herpes infection. Trigeminal neuralgia has been frequently documented as a cause of ‘atypical orofacial pain’ and ‘atypical odontalgia’. There are a few isolated case reports of acute pontine stroke resulting in ‘atypical orofacial pain’ and ‘atypical odontalgia’. However, pontine stroke as a cause of atypical odontalgia is limited to only a few cases, hence prevalence is not established. This case is one, where a patient presented with acute onset atypical dental pain with no identifiable dental etiology, further diagnosed as an acute pontine infarct on neuroimaging. A 40 years old male presented with acute onset, diffuse teeth pain on right side. Dental examination was normal. Magnetic resonance imaging(MRI) of the brain had an acute infarct in right pons near the trigeminal root entry zone(REZ). Pontine infarct presenting with dental pain as a manifestation of trigeminal neuropathy, has rarely been reported previously. This stresses on the importance of neuroradiology in evaluation of atypical cases of dental pain.
N-alkylphenothiazines - synthesis, structure and application as ligands in metal complexes
Authors: Krstic Milena , Sovilj Sofija , Borozan Suncica , Rancic Milica , Poljarevic Jelena , Grguric-Sipka Sanja
Published: September 2015

Phenothiazines are a large group of heterocyclic, aromatic molecules with
nitrogen and sulphur between two benzene rings. Their derivatives,
N-alkylphenothiazines have supstitutient on heterocyclic nitrogen atom which
gives them different properties. Also, a series of these molecules have
substitution on carbon atom at place 2 of phenothiazine benzene ring.
Alkylphenothiazines contain aminoalkyl substituent and their alkyl, acyl and
sulphonil derivatives, as well as monocyclic and bicyclic heterocycles
attached at thiazine nitrogen atom or directly linked to benzene ring. The
N-alkylphenothiazines have been known as antipsychotic drugs, but they also
possess antibacterial, antifungal, anticancer activity, and ability to react
with macromolecules and to coordinate to the metals. Metal complexes with
N-alkylphenothiazines are biological active compounds with different
antimicrobial activities and cytotoxic effect against tumor cell lines. Their
large field of application of N-alkylphenothiazines is very attractive in
terms of synthesis of new related derivatives, metal complexes, studying
their properties and applications. This article presents a review of the
literature and a contemporary view at N-alkylphenothiazines - their synthesis
and application, as well as their metal complexes which have promising
biological effects.
Midline shift threshold value for hemiparesis in chronic subdural hematoma
Authors: Jukovic Mirela , Stojanovic Dejan
Published: September 2015

Introduction. Chronic subdural hematoma (CSDH) has a variety of clinical
presentations, with numerous neurological symptoms and signs. Hemiparesis is
one of the leading signs that potentially indicates CSDH. Objective. Purpose
of this study was to determine the threshold (cut-off) value of midsagittal
line (MSL) shift after which hemiparesis is likely to appear. Methods. The
study evaluated 83 patients with 53 unilateral and 30 bilateral CSDHs in
period of three years. Evaluated computed tomography (CT) findings in
patients with CSDH were diameter of the hematoma and midsagittal line shift,
measured on non-contrast CT scan in relation with occurrence of hemiparesis.
Threshold values of MSL shift for both types of CSDHs were obtained as
maximal (equal) sensitivity and specificity (intersection of the curves).
Results. MSL is a good predictor for hemiparesis occurrence (total sample,
AUROC 0.75, p=0.0001). Unilateral and bilateral CSDHs had different threshold
values of the MSL for hemiparesis development. Results suggested that in
unilateral CSDH the threshold values of MSL could be at 10 mm (AUROC=0.65;
p=0.07). For bilateral CSDH the threshold level of MSL shift was 4.5 mm
(AUROC=0.77; p=0.01). Conclusion. Our study pointed on the phenomenon that
midsagittal line shift can predict hemiparesis occurrence. Hemiparesis in
patients with bilateral CSDH was more related to midsagittal line shift
compared with unilateral CSDH. When value of midsagittal line shift exceed
the threshold level, hemiparesis occurs with certain probability.
Influenza B viruses in the population of province of Vojvodina during the 2012/2013 season: Differentiation of B/Yamagata and B/Victoria lineages by real-time RT-PCR, antigenic and phylogenetic characterization
Authors: Radovanov Jelena , Milosevic Vesna , Hrnjakovic-Cvjetkovic Ivana , Ristic Mioljub , Djilas Milan , Nikolic Natasa , Patic Aleksandra , Kovacevic Gordana , Jovanovic-Galovic Aleksandra , Petrovic Tamas , Mikic Sandra
Published: September 2015

Introduction. At present, two phylogenetically distinct influenza B virus
lineages, B/Yamagata and B/ Victoria, co-circulate worldwide and can cause
significant morbidity and mortality. Objective. The aim of this study was to
determine the prevalences of two influenza B virus lineages in the population
of Vojvodina and to identify their antigenic and phylogenetic properties.
Methods. A total of 369 and 334 nasopharyngeal, or nasal/throat swab samples,
collected during the 2012/2013 and 2013/2014 seasons, respectively, were
tested using specific singleplex influenza A, influenza B, influenza
B/Yamagata and influenza B/Victoria real-time reverse transcription
polymerase chain reaction (RT-PCR) assays. Antigenic and genetic testing were
done by hemagglutination inhibition assay and hemagglutinin and neuraminidase
gene sequence analysis, respectively. Results. During the 2012/2013 season,
influenza B viruses were present in 53.4% (101/189) of influenza positive
samples. The B/Yamagata-like viruses (81.2%) significantly predominated over
the B/Victoria-like viruses (18.8%). Comparing to B/Victoria-like positive
patients, among B/Yamagata-like positive patients, children 5-14 years of age
were significantly more represented (5.3% vs. 35.4%, respectively), as well
as patients with mild form of illness (15.8% vs. 45.1%, respectively). The
results of sequence analysis and antigenic testing showed that tested viruses
were not closely related to B/Wisconsin/1/2010, the vaccine virus for
2012/2013. During the 2013/2014 season influenza B viruses were not detected.
Conclusion. The results of this study confirmed the health significance of
influenza B viruses and indicated that B/Yamagata-like viruses were
significantly more prevalent than B/Victoria lineage viruses, during the
2012/2013 season. They also showed a sub-optimal match between the tested
viruses and the vaccine virus for season 2012/2013.
Astasia-Abasia and Ganser syndrome in a preadolescent girl: A case report
Authors: Stankovic Miodrag , Kostic Jelena , Grbesa Grozdanko , Tosic Tatjana , Stankovic Sandra
Published: September 2015

Introduction. Astasia is the inability to maintain an upright body position
without assistance in the absence of motor weakness or sensory loss. Abasia
is described as the inability to walk or as uncoordinated walking, while
preserving mobility of the lower limbs. Ganser syndrome is described as a
dissociative disorder characterized by approximate answers, somatic
conversion symptoms, clouding of consciousness, as well as visual and
auditory pseudohallucinations. The aim of this study is to present a case
that seemed like a combination of neurological and internal disturbances, but
actually represented a psychogenic disorder. Case Outline. This paper
presents the case of a 13-year-old patient with the first manifestation of
the inability to walk and stand. Medical history, diagnostic instruments and
differential diagnostic methods have been presented in detail. The clinical
manifestation was initially interpreted as a neurological disorder. However,
after the application of diagnostic procedures and a change in family
circumstances, the patient was diagnosed with a psychogenic movement
disorder, astasia-abasia, with progressive clinical presentation that
included dissociative psychotic reactions (Ganser syndrome). Differential
diagnosis as well as the elements of the therapeutic approach have been
discussed. Conclusion. Presenting a case of psychogenic astasia-abasia in
children contributes to a better understanding and differentiating between
conditions with a clinical presentation of signs and symptoms dealt with by
other branches of medicine.
Hybrid procedure for a descending thoracic and subclavian artery aneurysm in a patient with previous abdominal aortic surgery: Case report
Authors: Radak Djordje , Tanaskovic Slobodan , Unic-Stojanovic Dragana , Jovic Miomir , Babic Srdjan , Sagic Dragan
Published: September 2015

Introduction. Hybrid procedures represent staged or simultaneous endovascular
and open surgical techniques in the treatment of complex pathologies of the
thoracic and abdominal aorta. We are presenting a patient with previous
abdominal aortic surgery in whom hybrid vascular procedure for descending
aorta and left subclavian artery aneurysm was performed. Case Outline. A
63-year-old female patient was admitted for computed tomography angiography.
Descending aorta aneurysm (7.6 cm) as well as aneurysm of the left subclavian
artery (LSA) was noted. Eight years ago she underwent abdominal aortic
aneurysm resection and aortoiliac bypass. Standard TEVAR (thoracic
endovascular aortic repair) procedure couldn?t be done due to small
dimensions of previous ?Y? graft (12.6 mm), so first we did LSA transposition
and after three days hybrid procedure. After ?Y? graft exposure, anastomosis
between the corps of ?Y? graft and tubular graft 10 mm was created and
through this conduit thoracic stent-graft was placed followed by complete ?Y?
graft replacement. After 6 months angiography showed regular postoperative
findings. Conclusion. Combined surgical and endovascular procedures in
thoracic aorta pathology treatment could be useful solutions with favorable
outcome.
Techniques of the tympanomastoidectomy with reconstruction of the posterior bone wall of the external auditory canal
Authors: Dankuc Dragan , Vlaski Ljiljana , Pejakovic Nemanja
Published: September 2015

A combined tympanoplasty method, the mobile-bridge tympanoplasty, has been
applied at the Clinic for Ear, Nose and Throat Diseases in Novi Sad since
1998. Mobile-bridge tympanoplasty is performed at our Clinic by applying
Feldmann?s procedure utilizing a microsurgical oscillating saw. It is a
combination of closed and open techniques for surgical treatment of middle
ear diseases. In addition to this technique, a method for reconstruction of
the posterior bone wall of the external auditory canal was introduced. This
procedure is applied in cases of damage or impairment of the bony ear canal
wall using mastoid cortical temporal bone graft or modeled cartilage of the
concha. Maintenance of general anatomical relations in the middle ear enables
good ventilation of pneumatic spaces of the middle ear and Eustachian tube
permeability, thus providing good conditions for ossicular chain
reconstruction. The incidence of recurrent cholesteatoma in combined
mobile-bridge tympanoplasty and tympanoplasty with reconstruction of the
posterior bone wall was 6% in total. The incidence values for the recurrent
cholesteatoma in closed tympanoplasty and in cases of open techniques were
10%. Mobile-bridge tympanoplasty and reconstruction of the posterior bone
wall of external auditory canal are methods of choice in surgical treatment
of middle ear cholesteatoma that progressed to the attic space, sinus tympani
and facial recess.
Benefits of student-centered tandem teaching in medical English
Authors: Antic Zorica
Published: September 2015

This paper addresses some of the key notions about English for special
purposes with special regard to English for medical purposes. The content was
determined by observations and based on authors? professional experience. The
starting point of a medical English course is a thorough analysis of
students? needs, which is then used in course design and definition of
appropriate learning goals. The student is at the center of learning and it
is necessary to establish a positive cooperation between students and
teachers. As medical English course is highly context-based, the inclusion of
medical teachers can offer many opportunities for a successful learning
process.
Climate change in East and Central Asia associated with the uplift of the Tibetan Plateau–A simulation with the MRI coupled atmosphere-ocean GCM
Authors: Abe Manabu , Yasunari Tetsuzo , Kitoh Akio
Published: September 2015

Himalayan Journal of Sciences Vol.2(4) Special Issue 2004 p.85-6
Plio-Pleistocene rapid uplift process of the Nepal Himalaya revealed from fission-track ages
Authors: Arita Kazunori , Ohira Hiroto
Published: September 2015

Himalayan Journal of Sciences Vol.2(4) Special Issue 2004 pp. 98-99
Renewed tectonic extrusion of high-grade metamorphic rocks in the MCT footwall since Late Miocene (Sutlej Valley, India)
Authors: Baudraz Vincent , Vannay Jean-Claude , Catlos Elizabeth , Cosca Mike , Vennemann Torsten
Published: September 2015

Himalayan Journal of Sciences Vol.2(4) Special Issue 2004 pp. 102-3
Deformation features of the Higher Himalayan Crystallines in Western Bhutan during exhumation
Authors: Carosi Rodolfo , Montomoli Chiara , Visonà Dario
Published: September 2015

Himalayan Journal of Sciences Vol.2(4) Special Issue 2004 pp. 108