bluuebunny/crossref_metadata_2025 huggingface dataset:
Properties Database of Working Medium for Full Scope Simulation of Coal-Fired Power Plant
Authors: Yu Tong , Yuan Jing Qi
Published: August 2013

A properties database of working medium is developed based on the IAWPS-IF97 mathematical model to satisfy the demand of the accurate properties of full scope simulation of coal-fired power plant. The database provides the continuous relationship of the specific enthalpy, the density and the specific heat capacity as the function of the pressure and temperature. On this basis, a graphical user interface is designed to ensure the database can be used as a separate software kit. The error caused by regression algorithm can be avoided in the properties database. The properties database is suit for full scope simulation of coal-fired power plants and can also be used in the nuclear power plant. The results show that a single-step execution of matrix calculation of the properties database costs no more than 1ms CPU time in the Pentium IV 1.6GHz computer, fast enough for most real-time applications. Compared with the Chinese Standard, the mean relative error of the properties is less than 0.1% in full operation scope.
The Prime Mover Selection Analysis of Distributed Energy System
Authors: Yuan Yan Zhou , Zheng Pu Yan , Chen Xiu Wen , Zhou Zhi Yun , Wang Jian Gang
Published: August 2013

The performance and application characteristic of various prime movers (gas turbines, gas engines and micro-turbines) were analyzed and compared; the criterion of selecting a DES prime mover was revealed and a method for designing the optimum capacity of a DES prime mover was given; The prime mover variable load characteristic, the impact of the start-stop and multi-station modular combination optimization are not fully considered, which will be the future research directions of DES configuration optimization .
Experimental Analysis of Effects of Non-Structural Factors on Performance of Liquid-Gas Ejector Driven by Aqueous LiBr Solution
Authors: Wang Rui , Gao Hong Tao
Published: August 2013

Miniaturization and high-efficiency plays an important role in the further development of absorption refrigeration. In order to improve the mass transfer efficiency, liquid-gas ejector is intended to be used in refrigeration system. Experimental analysis of effects of non-structural factors on Liquid-Gas Ejector driven by aqueous LiBr solution is presented. Solution concentration, solution temperature, evaporator temperature and back pressure are varied to analyze the ejector performance. The results show that the large difference between refrigerant vapor pressure and partial pressure of solution enhances absorption of water into aqueous lithium bromide solution. The optimal solution concentration range is 56.61wt%~57.61wt% when the throat diameter of convergent-divergent nozzle is 1.5mm. Cooling capacity increases with the decreasing of back pressure.
Dynamic Process of Generator Self-Excitation Considering the Load in Power Grid
Authors: Teng Yu Fei , Ding Li Jie , Zhang Hua
Published: August 2013

The dynamic process analysis of the generator self-excitation was proposed in this paper, considering the effect of the active power load in the isolated system. Firstly, generator self-excitation generation mechanism was introduced in this paper. Then, with a simple analysis system, two situations, which include the undercompensation system and the over compensation system, are discussed to analyze the dynamic process of the generator self-excitation phenomenon. Analysis results show that when there is the active power load in the isolated power system, the rotate speed of the generator in this system can be limited after the load rejection faults occurrence in system. Therefore, the overvoltage of the system caused by self-excitation can be limited obviously. Hence, the equipment in the system can be protected.
Reliability Evaluation of HVDC System Using FTA-FD Method Considering Different Capacities of AC Filters
Authors: Wang Xin Ze , Zeng Yuan , Xu Xuan , Li Jian She , Su Yin Sheng , Li Peng
Published: August 2013

HVDC technology is more and more common in practical projects, of which reliability will affect the whole power system. As different evaluation methods, FTA and FD method had their own advantages and disadvantages, this paper combined FTA method with FD method. Firstly FTA method was used to get basic parameters of each subsystem, then combined each subsystem to a whole equivalent model with FD method. What's more, different capacities of AC filters were also under consideration. Finally, an actual example was given to demonstrate validity of the method that this paper proposed. Compared with Zusim software, the result is more accurate.
Study on the Transition to Low-Carbon Electricity in Coal Industry in Shandong
Authors: Liu Zhong Wen , Gao Bin , Gao Peng Zhao
Published: August 2013

Economic development of Shandong province is over-reliance on coal resources, which produces shackles for the development of economy in Shandong. No matter from the current economic growth mode, the structure of energy consumption and current environmental pollution, the development model of economy in Shandong requires the transition to a low-carbon model, and there is an urgent requirement to go low carbon development path. This paper analysis that the energy structure in the presence of low carbon development of coal industry in Shandong province is not coordinated, the industrial structure is irrational, the extensive mode of development has not fundamentally change and there are some achievements in low carbon technology innovation and the development of circular economy. The paper provides the path for transition to low-carbon electricity in coal industry in Shandong through coal production, coal utilization, coal technology of low-carbon transition and other aspects.
A New Improved Decomposition Model Based on Laspeyres Index: A Case of CO2 Emission in China from 1996-2011
Authors: Wang Li Ning , Ma Ding , Chen Wen Ying
Published: August 2013

Due to some drawbacks of the Divisia inedex and its relevant decomposition methods, such as difficult affording accurate estimations in period-wise and cross-region decompositions with large discrete change data and involving logarithmic calculations. This paper introduces a new decomposition index based on Laspeyres index (LI), leaving no unexplained residuals. It distributes interactive term among related factors according to different contribution rates of each factor which are related to the changes of these factors. An empirical illustration, decomposing changes in CO2 emissions in China from 1996 to 2011 by both the proposed method (WLI) and Sun's Laspeyres index (SLI) methods time-series and period-wise methods, is carried out.
Predict Channel Sand Body Distribution Characteristics of South Eighth District Based on RMS Amplitude Attributes & Frequency Division
Authors: Hu Yu Shuang , Zhu Si Miao
Published: August 2013

A big tendency in oil industry is underestimating the heterogeneity of the reservoir and overestimating the connectivity, which results in overly optimistic estimates of the capacity. With the development of seismic attributes, we could pick up hidden reservoir lithology and physical property information from the actual seismic data, strengthen seismic data application in actual work, to ensure the objectivity of the results. In this paper, the channel sand body distribution in south eighth district of oilfield Saertu is predicted through seismic data root-mean-square amplitude and frequency division to identify sand body boundaries, predict the distribution area channel sand body characteristics successfully, which consistent with the sedimentary facies distribution. The result proves that seismic attribute analysis has good practicability in channel sand body prediction and sedimentary facies description.
Research Status of Gold Recovery from Thiosulfate Leaching Solution
Authors: Meng Qi , Cui Yi Qi , Tong Xiong , Dong Peng , Wang Kai
Published: August 2013

The main recovery methods of gold from thiosulfate leaching solution are introduced, such as replacement precipitation, carbon adsorption, ionexchange resin adsorption, and solvent extraction. Research status of different process and their advantages/disadvantages are reviewed briefly. The research prospects on the methods are also given.
Blank Unfolding Calculation for Blades of Stamping Welded Hydrodynamic Torque Converter
Authors: Tan Yue , Ma Wen Xing , Liu Chun Bao
Published: August 2013

Based on the total content of plastic deformation theory, this paper calculated blank unfolding of stamping welded hydrodynamic torque converter blades by applying the finite element inverse approach. Through numerical calculation for stamp forming of the blade blank unfolding, the calculation results showed that the size and shape of the blank forming results were consistent with three-dimensional blade design model. Using the finite element inverse algorithm we can obtain the initial blank shape of torque converter blades more precisely and rapidly, so as to accurately cut the blank material in the blade production stage.
Research on Communication Automation with Design and Implementation of FTP Based on Serv-U
Authors: Ji Hong
Published: August 2013

With the rapid development of network technology, communication automation system is widely used. It includes cabling system, broadband network system, mobile phone coverage system, cable and digital communication system. Use of the network is one of the functions of communication automation, and FTP (File Transfer Protocol) is one of the widely used protocols in the Internet. Based on the network platform, people use FTP service to transfer files and share information resources. The paper discusses the construction, working principle and access methods of FTP site. According to the security problems of FTP service, the paper researches on communication automation and proposes the security strategy of FTP technology. Combined with the engineering example, it introduces the concrete steps and methods of setting up FTP server based on server software Serv-U. Using FTP technology, it realizes allocation and rational use of information resources and also constructs a reliable, efficient, unified information platform. The FTP system runs normally.
Sonication Parameters Analysis of MWCNTs Monodispersion in Aqueous Solution of Triton X-100
Authors: Lu Shao Wei , Zeng Xian Jun , Nie Peng , Zhang Chun Xu
Published: August 2013

Monodispersion of multi-walled carbon nanotubes with assistance of surfactants has become a usual procedure. A parametric analysis of sonication was performed in order to optimize the preparation procedure of MWCNTs monodispersion solution. MWCNTs solutions were characterized with results of UV-VIS absorbance and FT-IR spectra in order to find the optimal sonication time and power. Perfect sonication time obtained at the higher absorption peak 2.699 in 400nm is 42min, which can be define as sonication cycle. MWCNTs can achieve its optimum dispersion situation, when onication power is 270w, In this case, zeta potential can get as high as-45.2mv. Film achieved under combination of two kinds of optimization parameters is more smoothy and integrated.
The Rate of Immune Escape Vanishes When Multiple Immune Responses Control an HIV Infection
Authors: van Deutekom Hanneke W. M. , Wijnker Gilles , de Boer Rob J.
Published: August 2013

During the first months of HIV infection, the virus typically evolves several immune escape mutations. These mutations are found in epitopes in viral proteins and reduce the impact of the CD8+ T cells specific for these epitopes. Recent data show that only a subset of the epitopes escapes, that most of these escapes evolve early, and that the rate of immune escape slows down considerably. To investigate why the evolution of immune escape slows down over the time of infection, we have extended a consensus mathematical model to allow several immune responses to control the virus together. In the extended model, most escapes also occur early, and the immune escape rate becomes small later, and typically only a minority of the epitopes escape. We show that escaping one of the many immune responses provides little advantage after viral setpoint has been approached because the total killing rate hardly depends on the breadth of the immune response. If the breadth of the immune response slowly wanes during disease progression, the model predicts an increase in the rate of immune escape at late stages of infection. Overall, the most striking prediction of the model is that HIV evolves a small number of immune escapes, in both relative and absolute terms, when the CTL immune response is broad.
Prevention of Hemoglobinopathies in Turkey
Authors: Çürük Mehmet Akif , Yalın Erdinç , Aksoy Kıymet
Published: August 2013

Hemoglobinopathies are the most common genetic disorders in Turkey. The incidence of beta thalassemia and sickle cell trait (HbAS) is 2.0% and 0.3% respectively. In addition to HbS, 51 abnormal hemoglobins and 42 different beta thalassemia mutations have been detected by DNA analysis. In Turkey, beta thalassemia and sickle cell anemia cause major health problems. For thirty years, screening programs for carriers, genetic counseling and prenatal diagnosis have sought to prevent hemoglobinopathies. In 1983, the first prenatal diagnosis center was established for sickle cell anemia and beta thalassemia at Hacettepe University, Ankara. After many populationscreening studies, a law was passed in 1993 by the Turkish Parliament for the eradication of hemoglobinopathies. Forty-one premarital screening centers were set up by the Ministry of Health in the 33 provinces where most of the transfusion-dependent thalassemic patients live. The mothers at risk for hemoglobinopathies were given genetic counseling and directed to prenatal diagnosis centers. Since 1990, four prenatal diagnosis centers have been established at university hospitals in Adana, Antalya, Istanbul and Izmir. A total of 5255 prenatal diagnoses have been made for sickle cell anemia and beta thalassemia in 5 centers; 1338 fetuses have been diagnosed as homozygous or compound heterozygotes for hemoglobinopathies. Prenatal diagnosis was performed on families who had decided to terminate the pregnancy if it were to be found that the fetus was affected.
The motivational value of rewards amongst Malawi’s health professionals
Authors: Chanza Alfred W.D. , Snelgar Robin J. , Louw Gerrit J.
Published: August 2013

Orientation: Reward administrators of Malawi’s health sector seem to misunderstand the intrinsic and extrinsic values of financial and non-financial rewards.Research purpose: This study focuses on assessing the motivational value of rewards amongst health professionals in Malawi’s Ministry of Health (MoH).Motivation for the study: Malawian studies indicate that Malawi’s MoH has become dysfunctional largely due to reward-related problems faced by its health professionals.Research design, approach and method: This study was a non-experimental design with an explanatory and evaluative approach, utilising both quantitative (questionnaire) and qualitative methods (literature review, interviews and focus group discussions).Main findings: The study confirmed the existence of reward-related problems amongst health professionals in Malawi’s MoH. Initially, statistical testing of the hypothesised model collapsed, suggesting that no relationship existed amongst the variables. However, statistical testing of the re-specified model suggests that there is a positive relationship between financial and non-financial rewards. Through the structural equation modeling (SEM) exercise, an inverse (negative) relationship between financial and non-financial rewards was established.Practical/managerial implications: The re-specified model symbolises a pragmatic departure from theoretical claims that financial rewards (salaries or money in general) are not a motivator. The graphic model suggests to managers and policy-makers that both financial and non-financial rewards are very important and valuable in any employment relationship.Contribution/value-add: An inverse (causal) relationship between financial and non-financial rewards has been established, graphically demonstrated and scientifically explained.
Endovascular treatment of hepatocellular carcinoma with drug eluting microparticles (DC-Beads): CT evaluation of response to the treatment
Authors: Boatta Emanuele , Corona Mario , Cannavale Alessandro , Fanelli Fabrizio , Cirelli Carlo , Medici Lorenzo de
Published: August 2013

Background and Study Aims: Our aim was to assess the efficacy and tolerability of drug-eluting beads-transarterial chemoembolization (DEB-TACE) in the treatment of hepatocellular carcinoma (HCC), evaluating the response to the treatment after 1, 6, 12, and 24 months with multidetector computed tomography (MDCT) comparing European Association for the study of the Liver (EASL) and modified Response Evaluation Criteria in Solid Tumors (mRECIST) criteria. Materials and Methods: We enrolled 154 patients with uni- or multifocal HCC who underwent a DEB-TACE. A total of 278 HCC nodules were treated. CT follow-up was performed at 1, 6, 12, and 24 months after the procedure according to the EASL and RECIST criteria evaluating overall target and target nodule response. We also analyzed the shrinking of nodules in relation to response to treatment. Results: A total of 278 nodules of HCC underwent TACE by using DC-Beads: At 24, months complete response was similar for EASL and RECIST criteria (112 vs. 121 nodules) with optimal accordance between methods and readers with k = 0.9. Partial Response resulted significantly different among the two methods within the first month, otherwise was similar after 24-month follow-up. Similar results in both methods were found for nodules classified as Stable Disease (P > 0.05). Progressive Disease results were similar in both the groups according to both the classification criteria without any significant difference (P > 0.05). Conclusion: Our study confirmed that EASL and mRECIST criteria are both effective methods for patient follow-up, however with some technical differences.
Acute stress-related psychological impact in children following devastating natural disaster, the Sikkim earthquake (2011), India
Authors: Mondal Rakesh , Banerjee Indira , Sabui Tapas , Saren Abhisek , Sarkar Sumantra , Hazra Avijit , Majumder Debabrata , Dutta Sudip , Pan Partha
Published: August 2013

Background: Psychological stress following natural disaster is common. Despite several earthquakes in India, data on evaluation of acute stress among the child victims in the early postdisaster period is scarce. Immediately following a devastating earthquake (6.9 Richter) at Sikkim on September, 18 2011, many children attended North Bengal Medical College, the nearest government tertiary care institution, with unusual stress symptoms. Objective: Evaluation of acute stress symptoms in children in the immediate postearthquake period. Materials and Methods: This was a cross‑sectional study done over 4 weeks and includes all the children from 1 to 12 years presenting with unusual physical or behavioral symptoms. Those with major injuries requiring admission were excluded. They were divided into two age groups. For older children (8-12 years) the 8‑item Children Impact of Event Scale (CIES) was used for screening of stress. Unusual symptoms were recorded in younger children (1-8 years) as CIES is not validated < 8 years. Result: A total of 84 children (2.66%) out of 3154 had stress symptoms. Maximum attendance was noted in first 3 days (65.47%) and declined gradually. In children ≥ 8 years, 48.78% had psychological stress, which was statistically significant on CIES scores without any gender predilection. Static posturing (41.86%), sleeplessness (32.55%), anorexia (9.30%), recurrent vomiting (13.95%), excessive crying (13.95%), or night‑awakenings (4.65%) were found in younger children (n = 43) and three required admission. Conclusion: This study represent the first Indian data showing statistically significant psychological impact in older children (8-12 years) and various forms of physical stress symptoms in young children (1-8 years) following earthquake.
The role of lumbar puncture and pressure.lowering therapy for transverse dural sinus thrombosis
Authors: Grant Joshua , Carey Andrew , Margo Curtis , Reed Murtagh , Drucker Mitchell
Published: August 2013

Transverse (lateral) sinus thrombosis is a well-known complication of acute otitis media and mastoiditis in the pediatric and adult population. Thrombosis involving the transverse sinus can ultimately cause elevation of intracranial pressure (ICP) as a result of decreased cerebrospinal fluid absorption. If treatment to lower ICP is not undertaken, it can lead to ophthalmological complications including irreversible vision loss. The following case report describes an 11-year-old girl who was diagnosed with AOM by her pediatrician and subsequently presented to the emergency department complaining of nausea, vomiting, headache, and diplopia.
Fourth ventricular ependymoma with a distant intraventricular metastasis: Report of a rare case
Authors: Ambekar Sudheer , Ranjan Manish , Somanna Sampath , Prasad Chandrajit , Santosh Vani
Published: August 2013

Ependymoma is one of the uncommon tumors of the central nervous system (CNS) in the adult age group. These tumors have a distinct propensity for metastasis, both within and outside the CNS. However, dissemination at the time of first presentation and retrograde dissemination of the tumor is rare. We report the case of a patient with fourth ventricular anaplastic ependymoma who presented with left lateral ventricular metastasis which was anatomically different from the primary tumor. We describe the clinic‑pathological detail of the patient and discuss the probable pathophysiological basis for this rare presentation and its significance in management of the patient.
Evaluation of outcome and prognostic factors in patients of glioblastoma multiforme: A single institution experience
Authors: Kumar Narendra , Kumar Pankaj , Angurana Shabab Lalit , Khosla Divya , Mukherjee Kanchan Kumar , Aggarwal Rupali , Kumar Ritesh , Bera Anjan , Sharma Suresh Chander
Published: August 2013

Aims: We present retrospective analysis of patients of glioblastoma multiforme (GBM) and discuss clinical characteristics, various treatment protocols, survival outcomes, and prognostic factors influencing survival. Materials and Methods: From January 2002 to June 2009, 439 patients of GBM were registered in our department. The median age of patients was 50 years, 66.1% were males, and 75% underwent complete or near-total excision. We evaluated those 360 patients who received radiotherapy (RT). Radiotherapy schedule was selected depending upon pre-RT Karnofsky Performance Status (KPS). Patients with KPS < 70 (Group I, n = 48) were planned for RT dose of 30-35 Gy in 10-15 fractions, and patients with KPS ≥ 70 (Group II, n = 312) were planned for 60 Gy in 30 fractions. In group I, six patients and in group II, 89 patients received some form of chemotherapy (lomustine or temozolomide). Statistical Analysis Used: Statistical analysis was done using Statistical Package for Social Sciences, version 12.0. Overall survival (OS) was calculated using Kaplan-Meier method, and prognostic factors were determined by log rank test. The Cox proportional hazards model was used for multivariate analysis. Results: The median follow-up was 7.53 months. The median and 2-year survival rates were 6.33 months and 2.24% for group I and 7.97 months and 8.21% for group II patients, respectively ( P = 0.001). In multivariate analysis, site of tumor (central vs. others; P = 0.006), location of tumor (parietal lobe vs. others; P = 0.003), RT dose (<60 Gy vs. 60 Gy; P = 0.0001), and use of some form of chemotherapy ( P = 0.0001) were independent prognostic factors for survival. Conclusions: In patients with GBM, OS and prognosis remains dismal. Whenever possible, we should use concurrent and/or adjuvant chemotherapy to maximize the benefits of post-operative radiotherapy. Patients with poor performance status may be considered for hypofractionated RT schedules, which have similar median survival rates as conventional RT.
Factors associated with death and predictors of one.month mortality from stroke in Kano, Northwestern Nigeria
Authors: Femi Owolabi Lukman , Mansur Nagoda
Published: August 2013

Background: In resource-poor setting, identification of predictors of death is of paramount importance for clinicians, so that specific therapies and management strategies can be applied to patients at high risk of dying. This study aims to determine the factors associated with death and predictors of in-patient mortality for stroke among a cohort of stroke patients in two tertiary centers in Northwestern Nigeria. Materials and Methods: This was a prospective study of consecutive patients with acute stroke who were admitted to tertiary hospitals in northwestern Nigeria. A single observer, using pre-defined diagnostic criteria, recorded the information of interest including length of stay, outcome (dead or alive all through 30 days), time of death. Result: A total of 273 patients comprising 179 male and 94 female stroke patients were recruited. One hundred and seventy-four (63.7%) had infarctive stroke while 99 (36.3%) had hemorrhagic stroke (91 intracerebral and 8 sub-arachnoid hemorrhage). One-month mortality was 37%, and the majority was patients with hemorrhagic stroke (69.6%). About two-third (74.5%) of the mortalities occurred during the first week of the event. Logistic regression showed that severe systolic blood pressure, severe diastolic pressure, second or more episode of stroke, severe GCS, seizures, abnormal pupillary size, hemorrhagic stroke type, presence of aspiration pneumonitis, RBS > 200 mg/dl were independent predictors of mortality in stroke. Conclusion: The present study provides information on factors associated with death in stroke. GCS < 8, seizures, abnormal pupillary size, hemorrhagic stroke, aspiration pneumonitis were independent predictors of mortality.
Equilateral Sets and a Schütte Theorem for
the 4-norm
Authors: Swanepoel Konrad J.
Published: August 2013

A well-known theorem of Schütte (1963) gives a sharp lower bound for the ratio of the maximum and minimum distances between n + 2 points in n-dimensional Euclidean space. In this note we adapt Bárány’s elegant proof (1994) of this theorem to the space . This gives a new proof that the largest cardinality of an equilateral set in is n + 1 and gives a constructive bound for an interval (4–εn, 4 + εn) of values of p close to 4 for which it is known that the largest cardinality of an equilateral set in is n + 1.
Simulation of Power-Law Fluid Flows in Two-Dimensional Square Cavity Using Multi-Relaxation-Time Lattice Boltzmann Method
Authors: Li Qiuxiang , Hong Ning , Shi Baochang , Chai Zhenhua
Published: August 2013

In this paper, the power-law fluid flows in a two-dimensional square cavity are investigated in detail with multi-relaxation-time lattice Boltzmann method (MRT-LBM). The influence of the Reynolds number (Re) and the power-law index (n) on the vortex strength, vortex position and velocity distribution are extensively studied. In our numerical simulations, Re is varied from 100 to 10000, and n is ranged from 0.25 to 1.75, covering both cases of shear-thinning and shear-thickening. Compared with the Newtonian fluid, numerical results show that the flow structure and number of vortex of power-law fluid are not only dependent on the Reynolds number, but also related to power-law index.
Exposing Laboratory-Reared Fleas to Soil and Wild Flea Feces Increases Transmission of Yersinia pestis
Authors: Jones Ryan T. , Vetter Sara M. , Gage Kenneth L.
Published: August 2013

Laboratory-reared Oropsylla montana were exposed to soil and wild-caught Oropsylla montana feces for 1 week. Fleas from these two treatments and a control group of laboratory-reared fleas were infected with Yersinia pestis, the etiological agent of plague. Fleas exposed to soil transmitted Y. pestis to mice at a significantly greater rate (50.0% of mice were infected) than control fleas (23.3% of mice were infected). Although the concentration of Y. pestis in fleas did not differ among treatments, the minimum transmission efficiency of fleas from the soil and wild flea feces treatments (6.9% and 7.6%, respectively) were more than three times higher than in control fleas (2.2%). Our results suggest that exposing laboratory-reared fleas to diverse microbes alters transmission of Y. pestis.
Ultrasonography and Birth Defects
Authors: Rao JP , Tomar Sakshi , Bora Rishabh , Bora Neharika Malhotra
Published: August 2013

Birth defects are major global problems. Even in developed countries, the incidence of birth defects has not reduced.

The prevalence of birth defects diagnosable (65%) and preventable (2.5%). Ultrasound screening is a very reliable tool for assessing birth defects.

A well done genetic scan at 11 to 14 weeks and at 22 weeks (TIFFA) can accurately detect over 85% of birth defects.

With the advent of 3D and 4D ultrasound, the accuracy for functional defects has also increased.

With the advent of 3D and 4D ultrasound, the accuracy for functional defects has also increased.

Each pregnancy deserves a prenatal diagnostic test and ultrasound is a near ideal diagnostic test to be applied, to large
pregnant population, specially in developing countries

How to cite this article

Malhotra N, Malhotra J, Tomar S, Malhotra Bora N, Rao JP, Bora R, Malhotra K. Ultrasonography and Birth Defects. Donald School J Ultrasound Obstet Gynecol 2013;7(2):149-159.
USG Role in Perinatal Infection
Authors: Ebrashy Alaa
Published: August 2013

Prenatal diagnosis can aid the obstetrician in evaluating a mother with suspected infection that can be transmitted to the fetus. The ultrasound (US) can exclude or identify anatomical defects of fetal heart, brain, detect thoracic or abdominal lesions, evaluate the liver and spleen volume, determine the degree of hemodynamic disturbance and suggest anemia. Congenital infections present with a wide spectrum of US markers and lesions, it may present as early pregnancy loss, nonimmune hydrops fetalis (NIHF), fetal growth restriction, CNS lesions, cardiothoracic lesions and lesions of the GIT.

Role of US-guided invasive procedures in fetal infections includes amniocentesis-chorionic villus sampling, percutaneous umbilical blood sampling.

How to cite this article

Ebrashy A. USG Role in Perinatal Infection. Donald School J Ultrasound Obstet Gynecol 2013;7(2):160-167.
Asymptomatic Simple Ovarian Cyst in Postmenopausal Women: Syndrome of ‘Visible Ovary’
Authors: Busse Raydeen , Zalud Ivica , Kurjak Biserka Funduk
Published: August 2013

Simple cysts of the ovary are quite common, with a prevalence of 5 to 17%. Advances in the technology of ultrasound and the increasing frequency of use of TVS has made it all the more important to have knowledge of the natural history of simple asymptomatic postmenopausal cysts. Previously, due to the paucity of data, postmenopausal women with asymptomatic simple cysts were managed much too aggressively. Current available data suggest a more conservative approach with serial ultrasounds, Doppler evaluation and CA-125 levels. Further studies are needed in order to have definitive guidelines for the gynecologic practitioner.

How to cite this article

Zalud I, Busse R, Kurjak BF. Asymptomatic Simple Ovarian Cyst in Postmenopausal Women: Syndrome of ‘Visible Ovary’. Donald School J Ultrasound Obstet Gynecol 2013;7(2):182-186.
The Assessment of Fetal Behavior of a Fetus with Lissencephaly by 4D Ultrasound
Authors: Yi҇iter Alin Ba͑gül , Gönenç Gökçenur , İŞḈi Herman , Güdücü Nilgün
Published: August 2013

Lissencephaly is malformation of gyral and sulcal structures of the cerebrum as a result of abnormal neuronal migration. The most common clinical manifestations of lissencephaly are severe psychomotor retardation, developmental defects, seizures, failure to thrive, and infant or early childhood deaths. Because direct assessment of functional development of the central nervous system in fetus and infant is not feasible, patients with lissencephaly who survive infancy are usually not diagnosed until childhood. Recently, the analysis of fetal behavior has been proposed as a measure of neurological maturation, which would be valuable in the diagnostic pathway of lissencephaly. In our knowledge the assessment of fetal behavior in a fetus with lissencephaly was not published yet in the literature.

How to cite this article

Yi—iter AB, Gönenç G, ¤Õçi H, Güdücü N. The Assessment of Fetal Behavior of a Fetus with Lissencephaly by 4D Ultrasound. Donald School J Ultrasound Obstet Gynecol 2013;7(2):208-212.
Ultrasound Assessment of Postpartum Fever
Authors: Tie Wayne , Tajnert Kathrene , O'Neill Thomas J
Published: August 2013

Postpartum fever and infection remain a significant cause of morbidity in postpartum period. Ultrasound is useful for assessment of the patients who present with temperature elevation, vaginal bleeding, pelvic and/or abdominal pain and signs of infection. Sonography can also be used to detect mastitis and breast abscess. Different types of imaging may be used in patients with refractory fever from suspected pyelonephritis, renal abscess and deep vein thrombosis. This article presents a variety of case scenarios regarding the postpartum fever. By using illustrative images the learner will be able to differentiate between the most common causes of postpartum fever, and will be able to identify typical B-mode, color Doppler, and CT images that require immediate antibiotic and/or invasive treatment.

How to cite this article

Tajnert K, Tie W, O'Neill TJ, Plavsic SK. Ultrasound Assessment of Postpartum Fever. Donald School J Ultrasound Obstet Gynecol 2013;7(2):219-230.
Divergent Approaches to Health-related Behavior Change: Pampering under NACP vs Persecution under RCH II
Authors: Singh Amarjeet , Jeyashree Kathiresan , Kathirvel Soundappan
Published: August 2013

Reproductive and Child Health Program II (RCH II) is essentially the largest program within the gamut of the National Rural Health Mission (NRHM) in India which aims to improve the maternal and child health indicators of the country. The program has evolved through various strategies and witnessed major policy changes that range from training traditional birth attendants (TBAs) to targeting 100% institutional deliveries. The TBAs who were earlier encouraged have almost eclipsed into extinction in the movement toward abolishing the practice of home deliveries. A contrasting scenario is observed in the strategies adopted under the NACP (National AIDS Control Program) like condom promotion and needle exchange which attempt to make the risky behavior safer. Applying the same rationale of NACP to RCH, one can justify the earlier practice of training TBAs and providing them with sterile kits to make home deliveries safer. While different strokes are required to solve different problems a difference in the fundamental ideology of two major National Health Programs has to be justified with solid evidence base.

How to cite this article

Jeyashree K, Kathirvel S, Singh A. Divergent Approaches to Health-related Behavior Change: Pampering under NACP vs Persecution under RCH II J Postgrad Med Edu Res 2013;47(3):148-149.
Carcinoma Expleomorphic Adenoma of the Submandibular Gland
Authors: Kudpaje Akshay , Gupta Sumit , Naik Sudhir , Halkud Rajshekar , Biswas Siddharth , Shenoy Ashok M , Chavan Purshottam , Kalloli Mahesh
Published: August 2013

Background and objectives

Carcinoma expleomorphic adenoma (CXPA) is a rare neoplasm of the salivary gland which arises in the epithelial component of a pleomorphic adenoma. It is not automatically a high-grade tumor as is traditionally suggested and should be further qualified as to type, grade of carcinoma and extent, since intracapsular and minimally invasive tumors behave favorably.

Setting

Department of Head and Neck oncosurgery, Kidwai Memorial Institute of Oncology, Bengaluru.

Case Report

A 38-year-old female was referred to our outpatient clinic with history of a painless swelling in the left side of the neck since 8 years. Fine needle aspiration revealed carcinoma of the submandibular gland. Contrast enhanced CT revealed a large heterogeneously enhancing mass lesion in the submandibular fossa with the gland not seen separately. Lymph nodes in level Ib and II were enlarged. Excision of the tumor revealed CXPA with foci of high grade mucoepidermoid carcinoma.

Conclusion

CXPA should no longer be considered a specific diagnosis but a category in which the carcinoma should be typed, graded and quantitated to impart more prognostically and therapeutically relevant data for efficient management.

How to cite this article

Naik SM, Shenoy AM, Chavan P, Halkud R, Biswas S, Kalloli M, Gupta S, kudpaje A. Carcinoma Expleomorphic Adenoma of the Submandibular Gland. J Postgrad Med Edu Res 2013;47(3):162-166.
Direct entrainment and detrainment rate distributions of individual shallow cumulus clouds in an LES
Authors: Dawe J. T. , Austin P. H.
Published: August 2013

Abstract. Probability distribution functions of shallow cumulus cloud core entrainment and detrainment rates are calculated using 4362 individual cumulus clouds isolated from LES (large eddy simulation) using a cloud tracking algorithm. Calculation of the mutual information between fractional entrainment/detrainment and a variety of mean cloud core properties suggests that fractional entrainment rate is best predicted by the mean cloud buoyancy B and the environmental buoyancy lapse rate dθρ/dz at that level, while fractional detrainment is best predicted by the mean vertical velocity w and the critical mixing fraction χc. Fractional entrainment and detrainment rates are relatively insensitive to cloud core horizontal area, and the perimeter of horizontal cloud core sections display an a0.73 dependence. This implies that cloud core mass entrainment flux E is proportional to cloud core cross-sectional area instead of cloud core surface area, as is generally assumed. Empirical best-fit relations for ε(B, dθρ/dz and δ(w, χc) are found for both individual shallow cumulus clouds and cloud ensembles. It is found that clouds with high buoyancy in strong stratification experience low entrainment rates, while clouds with high vertical velocities and critical mixing fractions experience low detrainment rates.
Similarities and differences of aerosol optical properties between southern and northern slopes of the Himalayas
Authors: Xu C. , Ma Y. M. , Yang K. , Zhu Z. K. , Wang J. M. , Amatya P. M. , Zhao L.
Published: August 2013

Abstract. The Himalayas is located at the southern edge of the Tibetan Plateau, and it acts as a natural barrier for the transport of atmospheric aerosols, e.g. from the polluted regions of South Asia to the main body of the Tibetan Plateau. In this study, we investigate the seasonal and diurnal variations of aerosol optical properties measured at the three Aerosol Robotic Network (AERONET) sites over the southern (Pokhara station and EVK2-CNR station in Nepal) and northern (Qomolangma (Mt. Everest) station for Atmospheric and Environmental Observation and Research, Chinese Academy of Sciences (QOMS_CAS) in Tibet, China) slopes of the Himalayas. While observations at QOMS_CAS and EVK2-CNR can generally be representative of a remote background atmosphere, Pokhara is an urban site with much higher aerosol load due to the influence of local anthropogenic activities. The annual mean of aerosol optical depth (AOD) during the investigated period was 0.06 at QOMS_CAS, 0.04 at EVK2-CNR and 0.51 at Pokhara, respectively. Seasonal variations of aerosols are profoundly affected by large scale atmospheric circulation. Vegetation fires, peaking during April in the Himalayan region and northern India, contribute to a growing fine mode AOD at 500 nm at the three stations. Dust transported to these sites results in an increase of coarse mode AOD during the monsoon season at the three sites. Meanwhile, coarse mode AOD at EVK2-CNR is higher than QOMS_CAS from July to September, indicating the Himalayas blocks the coarse particles carried by the southwest winds. The precipitation scavenging effect is obvious at Pokhara, which can significantly reduce the aerosol load during the monsoon season. Unlike the seasonal variations, diurnal variations are mainly influenced by meso-scale systems and local topography. In general, precipitation can lead to a decrease of the aerosol load and the average particle size at each station. AOD changes in a short time with the emission rate near the emission source at Pokhara, while does not at the other two stations in remote regions. AOD increases during daytime due to the valley winds at EVK2-CNR, while this diurnal variation of AOD is absent at the other two stations. The surface heating influences the local convection, which further controls the vertical aerosol exchange and the diffusion rate of pollutions to the surrounding areas. The Himalayas blocks most of the coarse particles across the mountains. Fine and coarse mode particles are mixed to make atmospheric composition more complex on the southern slope in spring, which leads to the greater inter-annual difference in diurnal cycles of Ångström exponent (AE) at EVK2-CNR than that at QOMS_CAS.
Borneo vortex and meso-scale convective rainfall
Authors: Koseki S. , Koh T.-Y. , Teo C.-K.
Published: August 2013

Abstract. We have investigated how the Borneo vortex develops over the equatorial South China Sea under cold surge conditions in December during the Asian winter monsoon. Composite analysis using reanalysis and satellite datasets has revealed that absolute vorticity and water vapour are transported by strong cold surges from upstream of the South China Sea to around the equator. Rainfall is correspondingly enhanced over the equatorial South China Sea. A semi-idealized experiment reproduced the Borneo vortex over the equatorial South China Sea during a "perpetual" cold surge. The Borneo vortex is manifested as a meso-α cyclone with a comma-shaped rainband in the northeast sector of the cyclone. Vorticity budget analysis showed that the growth of the meso-α cyclone was achieved mainly by vortex stretching. The comma-shaped rainband consists of clusters of meso-β scale rainfall patches. The warm and wet cyclonic southeasterly flow meets with the cold and dry northeasterly surge forming a confluence front in the northeastern sector of the cyclone. Intense upward motion and heavy rainfall result both due to the low-level convergence and the favourable thermodynamic profile at the confluence front. At both meso-α and meso-β scales, the convergence is ultimately caused by the deviatoric strain in the confluence wind pattern but is much enhanced by nonlinear self-enhancement dynamics.
A method to correct sampling ghosts in historic near-infrared Fourier transform spectrometer (FTS) measurements
Authors: Dohe S. , Sherlock V. , Hase F. , Gisi M. , Robinson J. , Sepúlveda E. , Schneider M. , Blumenstock T.
Published: August 2013

Abstract. The Total Carbon Column Observing Network (TCCON) has been established to provide ground-based remote sensing measurements of the column-averaged dry air mole fractions (DMF) of key greenhouse gases. To ensure network-wide consistency, biases between Fourier transform spectrometers at different sites have to be well controlled. Errors in interferogram sampling can introduce significant biases in retrievals. In this study we investigate a two-step scheme to correct these errors. In the first step the laser sampling error (LSE) is estimated by determining the sampling shift which minimises the magnitude of the signal intensity in selected, fully absorbed regions of the solar spectrum. The LSE is estimated for every day with measurements which meet certain selection criteria to derive the site-specific time series of the LSEs. In the second step, this sequence of LSEs is used to resample all the interferograms acquired at the site, and hence correct the sampling errors. Measurements acquired at the Izaña and Lauder TCCON sites are used to demonstrate the method. At both sites the sampling error histories show changes in LSE due to instrument interventions (e.g. realignment). Estimated LSEs are in good agreement with sampling errors inferred from the ratio of primary and ghost spectral signatures in optically bandpass-limited tungsten lamp spectra acquired at Lauder. The original time series of Xair and XCO2 (XY: column-averaged DMF of the target gas Y) at both sites show discrepancies of 0.2–0.5% due to changes in the LSE associated with instrument interventions or changes in the measurement sample rate. After resampling, discrepancies are reduced to 0.1% or less at Lauder and 0.2% at Izaña. In the latter case, coincident changes in interferometer alignment may also have contributed to the residual difference. In the future the proposed method will be used to correct historical spectra at all TCCON sites.
An automated GC-C-GC-IRMS setup to measure palaeoatmospheric δ13C-CH4, δ15N-N2O and δ18O-N2O in one ice core sample
Authors: Sperlich P. , Buizert C. , Jenk T. M. , Sapart C. J. , Prokopiou M. , Röckmann T. , Blunier T.
Published: August 2013

Abstract. Air bubbles in ice core samples represent the only opportunity to study the mixing ratio and isotopic variability of palaeoatmospheric CH4 and N2O. The highest possible precision in isotope measurements is required to maximize the resolving power for CH4 and N2O sink and source reconstructions. We present a new setup to measure δ13C-CH4, δ15N-N2O and δ18O-N2O isotope ratios in one ice core sample and with one single IRMS instrument, with a precision of 0.09, 0.6 and 0.7‰, respectively, as determined on 0.6–1.6 nmol CH4 and 0.25–0.6 nmol N2O. The isotope ratios are referenced to the VPDB scale (δ13C-CH4), the N2-air scale (δ15N-N2O) and the VSMOW scale (δ18O-N2O). Ice core samples of 200–500 g are melted while the air is constantly extracted to minimize gas dissolution. A helium carrier gas flow transports the sample through the analytical system. We introduce a new gold catalyst to oxidize CO to CO2 in the air sample. CH4 and N2O are then separated from N2, O2, Ar and CO2 before they get pre-concentrated and separated by gas chromatography. A combustion unit is required for δ13C-CH4 analysis, which is equipped with a constant oxygen supply as well as a post-combustion trap and a post-combustion GC column (GC-C-GC-IRMS). The post-combustion trap and the second GC column in the GC-C-GC-IRMS combination prevent Kr and N2O interferences during the isotopic analysis of CH4-derived CO2. These steps increase the time for δ13C-CH4 measurements, which is used to measure δ15N-N2O and δ18O-N2O first and then δ13C-CH4. The analytical time is adjusted to ensure stable conditions in the ion source before each sample gas enters the IRMS, thereby improving the precision achieved for measurements of CH4 and N2O on the same IRMS. The precision of our measurements is comparable to or better than that of recently published systems. Our setup is calibrated by analysing multiple reference gases that were injected over bubble-free ice samples. We show that our measurements of δ13C-CH4 in ice core samples are generally in good agreement with previously published data after the latter have been corrected for krypton interferences.