bluuebunny/crossref_metadata_2025 huggingface dataset:
The Vacancy Effect on Thermal Interface Resistance between Aluminum and Silicon by Molecular Dynamics
Authors: Zhang Yingying , Qian Xin , Peng Zhan , Yang Nuo
Published: February 2015

Thermal transport across interfaces is an important issue for microelectronics, photonics, and thermoelectric devices and has been studied both experimentally and theoretically in the past. In this paper, thermal interface resistance (1/G) between aluminum and silicon with nanoscale vacancies was calculated using non-equilibrium molecular dynamics (NEMD). Both phonon-phonon coupling and electron-phonon coupling are considered in calculations. The results showed that thermal interface resistance increased largely due to vacancies. The effect of both the size and the type of vacancies is studied and compared. And an obvious difference is found for structures with different type/size vacancies.
An REU in Glass Science – Lessons and Legacy for Undergraduate Materials Education
Authors: Heffner William , Jain Himanshu
Published: February 2015

Two important goals of the International Materials Institute for New Functionality in Glass (IMI-NFG) have been: (a) to facilitate international collaboration in glass research and, (b) to support the training of a professional workforce [1]. The REU program has been an important component of its mission since 2005. Glass science provides the central theme of our program, which has both an international and domestic component. In this paper we provide a summary of our accomplishments and experiences with this innovative, materials focused, multidisciplinary REU program. While glass provides the unifying theme of our program, the research topics and project advisers come from various departments, including not only materials science and engineering, but also biology, physics, environmental and civil engineering, electrical engineering, etc. This mode of REU operation has provided an effective means to introduce faculty from other departments to new, interdisciplinary applications of glass as an enabling material for their own work.

For the domestic REU, we partner with the Physics REU Program at Lehigh, sharing many crucial administrative aspects including housing, seminars and social events. The complementary approach of the two REU programs has been very beneficial to both of them. We summarize approaches to recruitment, selection and creating an environment conducive to cohesive and motivated community of young researchers. While the majority of student experiences have been through individual projects, we have also experimented with small teams headed by a single adviser. Because the teams can exploit the combined strengths of its members, they can accommodate a greater diversity of individual student skills and experiences. Such projects tend to provide opportunity for open-ended exploration within the context of a general goal. Some of the projects are specifically focused on developing low-cost, hands-on demonstrations for teaching glass science to others through a more experiential and intuitive approach. All of these REU projects have been incorporated in an on-line collection of activities for the science education community at large, as reported previously [2,3].

For the international component of REU, we have supported glass faculty in the country, who wish to engage their undergraduate students in a glass based summer research in the lab of an international colleague. These experiences require considerable preparation and individual attention. Here we discuss the challenges and successful strategies to deal with both the international and domestic programs.
Oxidation Protection of Multiphase Mo-Containing γ-TiAl-Based Alloys under Cyclic Test Conditions
Authors: Donchev A. , Pflumm R. , Galetz M. , Mayer S. , Clemens H. , Schütze M.
Published: February 2015

Intermetallic titanium aluminides solidifying via the disordered β-phase are of great interest for several high-temperature applications in automotive and aircraft industries. In this paper the thermocyclic oxidation behavior of three β-solidifying γ-TiAl-based alloys at 800°C and 900°C in air, with and without fluorine treatment, is reported for the first time. The behavior of the well-known TNM alloy (Ti-43.5Al-4Nb-1Mo-0.1B, in at.%) is compared with that of two Nb-free model alloys which contain different amounts of Mo (Ti-44Al-3Mo and Ti-44Al-7Mo, in at.%). During thermocyclic high-temperature exposure in air a mixed oxide scale develops on all three untreated alloys. Small additions of fluorine in the subsurface region of the alloys change the oxidation mechanism from mixed oxide scale formation to alumina at both temperatures. The oxidation resistance of the fluorine treated samples was significantly improved compared to the untreated samples.
Nanosecond Fast Switching Processes Observed in Gapless-Type, Ta2O5–Based Atomic Switches
Authors: Tsuruoka Tohru , Hasegawa Tsuyoshi , Aono Masakazu
Published: February 2015

The switching speed of a Cu/Ta2O5/Pt atomic switch between a high-resistance (OFF) state and a low-resistance (ON) state was evaluated by transient current measurements under the application of a short voltage pulse. It was found that the SET time from the OFF state to the ON state decreased as low as 1 ns, and the RESET time from the ON state to the OFF state reached a few ns using moderate pulse amplitudes. The switching time depends strongly on the pulse amplitude and the cell resistance before applying a voltage pulse. This observation indicates that oxide-based atomic switches hold potential for fast-switching memory applications. It was also found that Cu nucleation on the Pt electrode is likely to the rate-limiting process determining the SET time and the REST time appears to be preferentially determined by thermochemical reaction.
Symptom Accommodation Related to Social Anxiety Symptoms in Adults: Phenomenology, Correlates, and Impairment
Authors: Joogoolsingh Nayana , Wu Monica S. , Lewin Adam B. , Storch Eric A.
Published: February 2015

Background and Objectives: Socially anxious individuals often engage in various safety and avoidant behaviors to temporarily decrease distress. Similarly, friends or family members may engage in accommodating behaviors, commonly manifesting through the facilitation of avoidance, completion of tasks, or schedule modifications. Studies examining symptom accommodation in adult social anxiety are lacking, so this study seeks to better understand symptom accommodation and its consequent impairment in socially anxious adults. Design and Methods: There were 380 undergraduate students who completed a battery of self-report questionnaires through an online system. Constructs assessed include social anxiety, symptom accommodation, and impairment as well as related variables such as general anxiety, fear of negative evaluation, alcohol use, and anxiety sensitivity. Results: Symptom accommodation was positively correlated with social anxiety symptoms, functional impairment, general anxiety, anxiety sensitivity, fear of negative evaluation, and alcohol use. Individuals with considerable social anxiety reported significantly higher levels of symptom accommodation than individuals who reported lower levels of social anxiety. Anxiety sensitivity predicted symptom accommodation beyond the contribution of social anxiety. Symptom accommodation mediated the relationship between social anxiety and impairment. Conclusions: These data help elucidate the presentation and impact of symptom accommodation related to social anxiety. Implications for assessment, treatment, and future directions are presented.
Measuring Public Health Practice and Outcomes in Chronic Disease: A Call for Coordination
Authors: Porterfield Deborah S. , Rogers Todd , Glasgow LaShawn M. , Beitsch Leslie M.
Published: February 2015

A strategic opportunity exists to coordinate public health systems and services researchers’ efforts to develop local health department service delivery measures and the efforts of divisions within the Centers for Disease Control and Prevention’s National Center for Chronic Disease Prevention and Health Promotion (NCCDPHP) to establish outcome indicators for public health practice in chronic disease.

Several sets of outcome indicators developed by divisions within NCCDPHP and intended for use by state programs can be tailored to assess outcomes of interventions within smaller geographic areas or intervention settings.

Coordination of measurement efforts could potentially allow information to flow from the local to the state to the federal level, enhancing program planning, accountability, and even subsequent funding for public health practice.
Cervical Cancer Screening in a Sexually Transmitted Disease Clinic: Screening Adoption Experiences From a Midwestern Clinic
Authors: Meyerson Beth E. , Sayegh M. Aaron , Davis Alissa , Arno Janet N. , Zimet Gregory D. , LeMonte Ann M. , Williams James A. , Barclay Lynn , Van Der Pol Barbara
Published: February 2015

Objectives. We examined whether a sexually transmitted disease (STD) clinic could reach women who had not received a Papanicolau (Pap) test in the past 3 years. We also explored staff attitudes and implementation of cervical cancer screening.

Methods. Women (n = 123) aged 30 to 50 years were offered cervical cancer screening in an Indiana STD clinic. We measured effectiveness by the patients' self-reported last Pap test. We explored adoption of screening through focus groups with 34 staff members by documenting their attitudes about cervical cancer screening and screening strategy adaptation. We also documented recruitment and screening implementation.

Results. Almost half (47.9%) of participants reported a last Pap test 3 or more years previously; 30% had reported a last Pap more than 5 years ago, and 11.4% had a high-risk test outcome that required referral to colposcopy. Staff supported screening because of mission alignment and perceived patient benefit. Screening adaptations included eligibility, results provision, and follow-up.

Conclusions. Cervical cancer screening was possible and potentially beneficial in STD clinics. Future effectiveness-implementation studies should expand to include all female patients, and should examine the degree to which adaptation of selected adoption frameworks is feasible.
Regulatory Enforcement and Fiscal Impact in Local Health Agencies
Authors: Costich Julia F. , Rabarison Kristina M. , Rabarison Monika K.
Published: February 2015

Objectives. We used a cross-sectional, retrospective study design to analyze the association between local health agency regulatory activities and revenues from nonclinical fees and fines (NFF).

Methods. We extracted data from the 2010 National Association of County and City Health Officials (NACCHO) Profile Survey, the most recent report including NFF information, and used 2-part multivariable regression models to identify relationships between regulatory activities and revenue. We also interviewed LHD directors on access to revenue from fines.

Results. NFFs generated substantial revenue for most LHDs, increasing in scope and amount with jurisdiction size for all but the largest municipalities. The greatest proportion of net revenue came from public pools, campgrounds and recreational vehicles, and solid waste disposal. For small and mid-sized LHDs, enforcement activities generated revenue in a dose–response pattern, with higher returns for increased activities. LHDs in decentralized governance states collected more NFF revenue than those in centralized states. States vary regarding LHD access to revenue from sanctions.

Conclusions. The fiscal impact of changes in regulatory activity needs careful assessment to avoid unanticipated consequences of applicable law.
The Impacts of Local Health Department Consolidation on Public Health Expenditures: Evidence From Ohio
Authors: Hoornbeek John , Morris Michael E. , Stefanak Matthew , Filla Joshua , Prodhan Rohit , Smith Sharla A.
Published: February 2015

We examined the effects of local health department (LHD) consolidations on the total and administrative expenditures of LHDs in Ohio from 2001 to 2011.

We obtained data from annual records maintained by the state of Ohio and through interviews conducted with senior local health officials and identified 20 consolidations of LHDs occurring in Ohio in this time period. We found that consolidating LHDs experienced a reduction in total expenditures of approximately 16% (P = .017), although we found no statistically significant change in administrative expenses.

County health officials who were interviewed concurred that their consolidations yielded financial benefits, and they also asserted that their consolidations yielded public health service improvements.
Emerging Frontiers: State of the Society
Authors: Spath Jeff
Published: February 2015

President's column

This is my final column and I will use it to update you on the state of the society in the context of my goals for the year and the status of the strategic initiatives adopted last year by the SPE Board of Directors.

Let me begin by stressing that by all objective measures, SPE continues to be a highly successful organization with impressive growth rates in its annual membership, professional section, and student chapters; a significant increase in the number and quality of member-requested meetings; and a strong financial position. In addition, over the past year, SPE has added several valuable programs and services, expanded the reach of its programs geographically and topically, strengthened our offices around the world, and collaborated with an increasing number of other organizations to create greater value for our members and the industry as a whole.

Strategy Implementation

With respect to the new strategy that I was charged with implementing, I am pleased to say that much progress has been made in each of the four initiatives. The priority of competency development happened to coincide with a personal goal of mine to address the industry challenges and the SPE opportunities around management of the “big crew change.” For example, accelerating competency development and reducing the time to autonomous decision making form a large part of the crew-change solution and offer a huge opportunity to strengthen and grow SPE training. In the last year, SPE has provided 188 training courses to 3,491 attendees vs. 115 courses to 2,377 attendees in 2012, an increase of 47% and 63%, respectively. With the rollout of the free SPE Competency Assessment program at the upcoming Annual Technical Conference and Exhibition (ATCE) in Amsterdam, I expect the training metrics to continue to grow significantly.

Increasing the petroleum engineering faculty numbers and supporting faculty development and retention is another necessary tactic in addressing the issue of today’s industry demographics. In this area, we have added a permanent faculty position to the Board of Directors in order to understand and solve academic issues pertaining to industry needs and demands. Last year, we also reintroduced the Petroleum Engineering Education Colloquium, which successfully brought together industry and academic leaders to discuss and resolve issues on educating the next generation of graduates. I would like to thank Cindy Reese, Technical Director for Management and Information, for enhancing the dialogue and increasing our focus on faculty attraction and retention.
2013 Education Forum - Milestones in the First Year
Authors: Chase R. , Reece C.
Published: February 2015

Talent & Technology

As capability development is one of its key strategic objectives, SPE sponsored a forum in August 2013 on the need to ensure an appropriately educated upstream engineering workforce in 2020 and beyond. The attendees concluded that our petroleum engineering educational systems will be significantly challenged to produce the qualified talent that the oil and gas industry will need in 2020 unless the industry and academia make this issue a priority and collaborate on ways to resolve the anticipated underlying gaps (SPE-169906- WP). Forum participants volunteered to champion specific and actionable initiatives designed to help improve our industry’s ability to meet its resourcing needs in the next decade. As we mark the first anniversary of the forum, here are some of the efforts being advanced by the participants.

Sharing Resources. Laboratories are a key challenge for many educational institutions for several reasons. Higher-than-normal enrollments put pressure on having adequate laboratory space for all students to complete laboratory requirements. Additionally, laboratory equipment at many universities is in need of upgrade due to technology advancements. Most schools are unable to increase or upgrade their laboratory space or equipment because of limited funds. With the advent of automated laboratory equipment, the capability of sharing laboratories virtually is one of the initiatives that forum participants were interested in exploring. One forum team conducted a pilot survey of schools in the United States to determine the laboratory capabilities at each school, and their needs and level of interest in sharing facilities either physically or virtually. Several schools have indicated an interest in sharing facilities. The next step is to conduct a pilot to test the concept.

Another resource sharing opportunity that has made progress is a secure website where design problems, data sets, etc., can be shared among faculty. The next steps involve the faculty uploading materials that they would like to share on the website and to promote the website to faculty.
Technology Focus: Drilling Management and Automation (September 2014)
Authors: Cunha J.C.
Published: February 2015

Technology Focus

If you look for the meaning of “automation,” you will find a definition such as “automatically controlled operation of an apparatus, process, or system by mechanical or electronic devices that take the place of human labor.” Another definition is “the technique of making an apparatus, a process, or a system operate automatically.”

I prefer the second one, not only because there is no mention of any replacement of human labor, but also because it implicitly calls for human interaction. It is the “technique of making,” and we are the ones making. That is the reason this section is called Drilling Management and Automation. We are interested in the state of the art of automated tools that will help us manage our operations better, making them more efficient and safer. Right now, our industry is involved in the development of several automated tools and processes to improve the quality of drilling operations. Early kick detection, smart blowout-preventer activation, automated managed-pressure-drilling systems, intelligent wellbore steering/positioning, and seismic while drilling are some of the areas with remarkable developments in recent years.

These tools and systems are already allowing a much safer, more controlled, and more efficient operation. And the ability to position the wellbore in the ideal spot, a dream for engineers and geologists alike, is very close to becoming a reality. And this will be delivered with improved performance and operational safety, which is ultimately what drilling management is all about. Two years ago, at the SPE Annual Technical Conference and Exhibition in San Antonio, Texas, while talking at the Subsurface Hydrocarbon Containment luncheon, I used the expression “well control” and emphasized to the audience that I was not referring to operations performed when a well is kicking and has to be controlled. Instead, the intended meaning was related to a drilling operation in which the well is under control 100% of the time—no kicks, no wellbore collapses, no incidents. Sensible management and automated tools and systems can make this possible.

All of the selected articles for this month have good examples of improved performance through the use of automation; but, most important, they bring outstanding examples of our profession’s inventiveness and superb drilling-operations management. Enjoy. JPT
Influences on the thermomechanical fatigue crack growth of the nickel alloy 617*
Authors: Schlesinger Michael , Schweizer Christoph , Brontfeyn Yakiv
Published: February 2015

The following contribution deals with the experimental investigation and theoretical evaluation of fatigue crack growth under isothermal and non-isothermal conditions at the nickel alloy 617. The microstructure and mechanical properties of alloy 617 are influenced significantly by the thermal heat treatment and the following thermal exposure in service. Hence, a solution annealed and a long-time service exposed material condition is studied. The crack growth measurement is carried out by using an alternate current potential drop system, which is integrated into a thermomechanical fatigue (TMF) test facility. The measured fatigue crack growth rates results in a function of material condition, temperature and load waveform. Furthermore, the results of the non-isothermal tests depend on the phase between thermal and mechanical load (in-phase, out-of-phase). A fracture mechanic based, time dependent model is upgraded by an approach to consider environmental effects, where almost all model parameters represent directly measureable values. A consistent description of all results and a good correlation with the experimental data can be achieved.
Ratcheting behavior of bearing support structures during windmilling in aero engines*
Authors: Narayanan Govindarajan , Rezaei Khosrow
Published: February 2015

A major safety concern in commercial civil aviation is losing a fan blade from jet engine during its normal operation either due to bird strike or limited fatigue. The assessment of fatigue strength of the support structures like bearing and intermediate connection in aero engine during windmilling has become an essential requirement for safe-fly-home situation. Windmilling is the rotation of a non-operating engine due to the airflow induced forces on the blades caused by the forward motion of the aircraft. The imbalanced rotation during windmilling post fan blade off (FBO) creates unavoidable vibratory loads in transient nature which leads to shorter fatigue life of the support structures. Since the repeated imbalance loads beyond elastic limit of the structure can cause the accumulation of plastic deformation, which exceeds the critical strain limit of the structure. This article deals with the ratcheting behavior (low cycle fatigue) of bearing support structures during windmilling post FBO in aero engine. When the accumulated plastic strain exceeds the critical strain limit of the bearing structure, then it experiences ratcheting fatigue failure.
Is this Seat Taken?
Authors: O'Malley Tara , Vaishnav Maulik
Published: February 2015

The Chicago Transit Authority (CTA) in Illinois conducted a research study to inform the purchase of rail cars. The study comprised customer surveys, qualitative observations of customer behavior, and quantitative analysis of station dwell times. Traditionally, CTA rail cars were configured with transverse seats of various quantities, standing areas, and supporting infrastructure for standees, such as poles. Since November 2011, CTA has been phasing in the 5000-series car, which offers longitudinal seats with the potential for more standing room and increased capacity especially during peak periods. The study reported in this paper used multiple methodologies to compare customer preference, passenger flow and behavior, and train operation of three rail car types on the basis of the impact of seat configuration. Results indicated that most customers preferred transverse seats. Rail cars with longitudinal seats were unable to accommodate more people than other cars, because the varied length of people's legs restricted room for standing riders. Customers found comfortable standing spaces in existing 3200-series cars with 2 × 1 seating, which created staggered standing room in the center aisle. The availability of many poles in this series and fewer weather panels led to shortened dwell times and increased capacity. The study questioned whether longitudinal seats could increase car capacity. Contrary to theoretical estimates and expectations, CTA found no evidence that more standing room increased car capacity. Further research is encouraged on systems in which rail cars differ in their dimensions from narrow CTA rail cars to understand how customer interactions and preferences for other seating configurations affect rail car capacity.
Significance of ST-segment Depression during Paroxysmal Supraventricular Tachycardia
Authors: Zaman Shahana , Sayami Lima Asrin , Rahim Muhammad Abdur , Islam AKM Monwarul , Ullah Mohammad , Nabi Shaila , Ali M Atahar
Published: February 2015

Background: ST-segment depression in ECG is a common finding during paroxysmal supraventricular tachycardia. The exact mechanism and etiology of this ST-segment depression is not always evident. In this study we have tried to evaluate the significance of ST-segment depression during supraventricular tachycardia. Methods: Hospitalized patients for elective electrophysiological study with previous (EPS) history of supraventricular tachycardia with or without ST-segment depression were evaluated clinically, by coronary angiogram and EPS. Data were analyzed by appropriate statistical methods and comparison made between groups with ST-segment depression (Group A) and without ST-segment depression (Group B). Results: Total number of patients was 66. Equal number of patients (33) was in each group. The mean age of patients was 43.8 years. There was female predominance (M:F ratio 2:3). The mean heart rate during supraventricular tachycardia was 161 beats/min. Age, sex, coronary artery disease risk factors and heart rate during an episode of supraventricular tachycardia did not have any significant influence on ST-segment depression. Significant coronary artery disease was found in two patients in Group A and one patient in Group B. Electrophysiological study revealed that Atrio ventricular reentry tachycardia (AVRT) and AV nodal reentry tachycardia (AVNRT) were present in 28 (42.4%) and 38 (57.6%) cases respectively. Patients of group A exhibit AVRT significantly more than patients of group B.The sensitivity of ST-segment depression in correctly diagnosing coronary artery disease (CAD) was 66.7% while the specificity was 50.8%. The sensitivity of ST-segment depression in correctly differentiating AVRT was 83.3% while the specificity was 66.7%. The positive predictive value (PPV) and Negative predictive value (NPV) of the test were 75% and 76.9% respectively. Conclusion: ST-segment depression during episode of supraventricular tachycardia is a poor indicator of coronary artery disease. Presence of ST-segment depression can differentiate AVRT from AVNRT. However, >2 mm ST-segment depression was proved to be an excellent predictor of AVRT. DOI: http://dx.doi.org/10.3329/cardio.v7i2.22249 Cardiovasc. j. 2015; 7(2): 93-97
Association of Hypertension on Development of Coronary Collaterals in Severe Coronary Artery Disease
Authors: Hossain Solaiman , Majumder Abdullah Al Shafi , Ullah Mohammad , Shaha Chandan Kumar , Mannan Md Abdul
Published: February 2015

Objectives: Coronary collaterals appear to play important role in coronary artery disease morbidity and mortality. In this study it was intended to determine whether hypertension is associated with development of coronary collaterals in patients with severe coronary artery disease. Methods: This was an observational cross-sectional study carried out in the department of cardiology of National Institute of Cardiovascular Diseases, Dhaka, Bangladesh during the period from October 2010 to June 2011. A total of 334 patients were examined to include in the study. Among them 118 patient of severe coronary artery disease (CAD) were included who fulfilled the inclusion and exclusion criteria. From where 63 patients were CAD with hypertension (Group -I) and 55 patients were CAD without hypertension (Group -II). Based on Rentrop Grading the study patients were divided in two groups, patients with poor collaterals (Grade 0& 1) and good collaterals (Grade 2&3). Data compared the coronary collaterals in hypertensive patients with those without hypertension with severe coronary artery disease. Results: The data showed that good collateral circulations were higher with duration of hypertension. The difference were statistically significant in duration <5 years and duration >10 years in both groups (p<0.05). The pattern of vessel involvement in double vessel disease and triple vessel disease (p <.001) and dyslipidemia (p<0.004) appeared to be significant predictor of hypertension controlling for other factors in the model. People with hypertension are around four times more likely to have good collateral circulation, multiple vessel disease and around 12 times more likely to have dyslipidemia. Conclusion: It is concluded that the patients of hypertension develop higher grades of coronary collaterals which increases with duration of hypertension in patients of severe coronary artery disease. Involvements of coronary arteries were more extensive in patients of hypertension with coronary artery disease. DOI: http://dx.doi.org/10.3329/cardio.v7i2.22250 Cardiovasc. j. 2015; 7(2): 98-103
Prevalence of Hypertension among the Bangladeshi Adult Population: A meta-analysis of Studies between 2004 and 2014
Authors: Chowdhury Shaibal , Chowdhury Purnima
Published: February 2015

Background: Hypertension has become a significant problem in many developing countries undergoing epidemiological transition from communicable to non-communicable chronic diseases. Previous studies covering up to 1999 reported a prevalence of ll.3% in the adult population of Bangladesh. Methods: We have searched National Institute of Cardiovascular Diseases (NICVD) Library and PubMed@ Resources Guide for published Hypertension prevalence studies between 2004 and 2014. A meta-analysis was conducted to estimate the prevalence of hypertension among the adult Bangladeshi population. We have considered population-based studies that had a clear definition of hypertension, and were conducted in adults (>18 years). We have marked seventeen articles, of which only six articles fulfill the selection criteria were included for the current analysis. Then the prevalence of hypertension and their 95% CIs for the individual studies were calculated by using the data presented. Finally a pooled estimate was obtained from six studies. Results: The pooled estimate for the prevalence of hypertension in 2972 adults was 20.88% (18.75% - 22.87%) which almost double than the previous estimated value. Conclusion: The meta-analysis clearly demonstrates the high burden of hypertension among the adult population of rural Bangladesh and underscores the importance of instituting screening for asymptomatic individuals with potentially harmful hypertensive disorder, especially in primary health-care settings to combat the growing epidemic of Noncommunicable Diseases. Large scale studies can be done including all the high risk population to represent the actual scenario of hypertension in Bangladeshi adult population. DOI: http://dx.doi.org/10.3329/cardio.v7i2.22251 Cardiovasc. j. 2015; 7(2): 104-107
Association of Creatinine Clearance Rate and Coronary Angiographic Severity in Patients with Coronary Artery Disease
Authors: Hossain Mofazzal , Khan HI Lutfur Rahman , Chowdhury Abdul Wadud , Abdullah Abu Sadique , Amin Md Gaffar , Alam Mohammad Sarwar , Kabir SM Eftar Jahan , Khan Tunaggina Afrin , Faruk Chowdhury Omar
Published: February 2015

Background: In epidemiological studies and clinical trials renal function has been shown to be an independent predictor of coronary artery disease (CAD). We conducted this study to find out the association between creatinine clearance rate (CCr) and coronary angiographic severity in patients with (CAD). Method: It was a cross sectional study carried out in the department of Cardiology, Dhaka Medical College Hospital, Dhaka during the period of April, 2011 to March, 2012. All the patients with Ischaemic heart disease (IHD) admitted in the department of Cardiology who fulfill the inclusion and exclusion criteria and underwent coronary angiogram were taken as sampling population. Sampling technique was purposive and sample size was 118. By Cockcroft-Gault formula, CCr was estimated from serum creatinine. Coronary angiographic severity of coronary artery disease was assessed by vessel score and stenosis score. Statistical analysis was carried out by descriptive statistics, correlation coefficient test and one way ANOVA test. Level of significance was set at 0.05. Results: Mean CCr among study subjects was 72.57 ± 17.78 ml/min. Vessel score showed 18.6% had normal coronaries, 37.3% single vessel disease, 31.4% double vessel disease and 12.7% triple vessel disease. There was significant positive relationship between serum creatinine and vessel score, and also negative relationship between CCr and vessel score. The study also showed significant negative correlation between CCr and stenosis score. Conclusion: Angiographic severity of coronary artery disease is associated with degree of renal dysfunction. Decreased creatinine clearance is associated with more extensive CAD. DOI: http://dx.doi.org/10.3329/cardio.v7i2.22257 Cardiovasc. j. 2015; 7(2): 108-113
Association of Atherosclerotic Renal Artery Stenosis with Coronary Artery Disease
Authors: Sen Krishna Kanta , Ali Mahboob , Choudhury Amal Kumar , Karmakar Pradip Kumar , Khalequzzaman Md , Akhtaruzzaman Md , Ulubbi Salahuddin , Rahman Md Arifur , Kabir Md Shaheeen , Badiuzzaman Md , Islam Sharafat Nurul , Roy Bithi Rani
Published: February 2015

Background: The association between extent and severity of coronary artery disease (CAD) and renal artery stenosis (RAS) has been well established in many studies. The aim of this study was to assess the incidence and severity of RAS in patients with CAD. Methods: Coronary angiogram (CAG) and renal angiogram was done in standard protocol. A total of 95 patients was included in the study and divided into two groups according to the presence of significant renal artery stenosis. In Group I 45 patients were having normal or insignificant renal artery stenosis. In Group II 50 patients were having significant renal artery stenosis. All data were recorded systematically in preformed data collection form. Results: In Group I, most common CAG findings were single vessel disease (SVD) (91.1%), triple vessel disease (TVD) (2.2%) and double vessel disease (DVD) (6.7%). No patients in Group I had Left Main (LM) disease. In Group II, most common CAG findings were DVD (42.0%) followed by SVD 32.0%, TVD 26.0% and LM 8.0%. There is statistically significant difference in Vessels Score, Friesinger Score and Leaman Score between the groups (p<0.05). Conclusion: The study revealed significant association between atherosclerotic renal artery stenosis (RAS) and severity of coronary artery disease (CAD). This indicates significant atherosclerotic renal artery stenosis (RAS) predict the severity of coronary artery disease. DOI: http://dx.doi.org/10.3329/cardio.v7i2.22258 Cardiovasc. j. 2015; 7(2): 114-118
Role of Echocardiographic Imaging in Percutaneous Balloon Mitral Valvotomy
Authors: Sharma Satyavan , Kolekar Satishkumar Suresh
Published: February 2015

Mitral stenosis (MS) is a still frequently encountered in India and Bangladesh. Untreated MS contributes to the morbidity and mortality. Balloon mitral Valvotomy is effective and commonly used for relief of obstruction in symptomatic patients. The case selection is guided by clinical characteristics and imaging. Echocardiography is the most important imaging modality to assess severity of obstruction its hemodynamic consequences as well as valve morphology. Transthoracic two dimensional echocardiography is usually sufficient to provide the desired information. Trans esophageal echocardiography is used when the valve cannot be adequately assessed by trans thoracic echocardiography and to exclude intracardiac thrombi prior to intervention. Three dimensional transthoracic and trans esophageal echocardiographic assessment provides more elaborate physiological and morphological information. DOI: http://dx.doi.org/10.3329/cardio.v7i2.22261 Cardiovasc. j. 2015; 7(2): 128-136
Prevention of Hypertension in Bangladesh: A Review
Authors: Biswas Tuhin , Islam Sheikh Mohammed Shariful , Islam Anwar
Published: February 2015

Background: Hypertension is a major public health problem in both the developed and developing countries and the leading cause of morbidity and mortality globally. The risk factors for hypertension, which can largely be prevented through simple health promotion and preventive measures, are mostly known. However, evidence on strategies for prevention of hypertension in Bangladesh is not available. The aim of this review study was to identify and discuss different approaches to prevent hypertension in Bangladesh. Methods: We performed a systematic search using electronic as well as manual methods for published and unpublished reports of prevention of hypertension. We then identified and discussed prevention strategies for hypertension suitable for Bangladesh context. Results: Several methods have shown to prevent hypertension. However, the challenge remains in implementing these methods in resource poor settings. Integrated action based on comprehensive policy and stepwise implementation should be adopted taking into consideration of local needs. Hypertension prevention should focus on awareness generation, health promotion and reduction of common risk factors using a combination of population based approach and targeted individual interventions. Conclusion: Consorted actions should be taken as a priority to prevent hypertension through intersectoral, multidisciplinary and multilevel approach by the Government and stakeholders for creating greater awareness and healthy life-style. DOI: http://dx.doi.org/10.3329/cardio.v7i2.22262 Cardiovasc. j. 2015; 7(2): 137-144
Infective Endocarditis in a ?-thalassemia Major Child
Authors: Rahayuningsih Sri Endah , Kuswiyanto Rahmat Budi , Situmorang Herdiana Elizabeth , Phangkawira Evelyn
Published: February 2015

Almost all patients who develop infective endocarditis (IE) had history of congenital or acquired heart disease.We report a 9 years old boy who was diagnosed as ?-thalassemia major since age 1.5 years, admitted to hospital with chief complaint of difficulty of breathing for 1 week before admission, accompanied by fever. Holosystolic murmur of grade 3/6 was found in the lower left sternal border along with hepatosplenomegaly. Chest x-ray depicted right ventricle enlargement and opaque densities in the middle field of left lung. Blood culture showed growth of Staphylococcus aureus. Echocardiography detected thickening tricuspid valve with oscillating mass in the tricuspid valve, severe pulmonary hypertension, and minimal pericardial effusion. Diagnosis of IE was made. After clinical improvement he was discharged with good condition. The diagnosis of IE in children without heart defects is difficult to establish and right-sided IE is rare in children that a high suspicion index should be considered. DOI: http://dx.doi.org/10.3329/cardio.v7i2.22263 Cardiovasc. j. 2015; 7(2): 145-149
Transcatheter Closure of Ventricular Septal Rupture First in Bangladesh - A Case Report
Authors: Momenuzzaman NAM , Hossain Solaiman , Begum Fatema , Khan Kaisar Nasrullah , Shafique AM , Sohail KM
Published: February 2015

Ventricular septal rupture is a rare complication of acute myocardial infarction with important hemodynamic consequences. Without a rapid diagnosis and correction by surgical intervention, the short-term mortality of these patients is higher than 90%. Early diagnosis is based on clinical examination and transthoracic echocardiography. Transcatheter closure of ventricular septal rupture in selected patients may save lives. We report a patient with ventricular septal rupture in acute myocardial infarction that was closed by an Amplatzer device. DOI: http://dx.doi.org/10.3329/cardio.v7i2.22264 Cardiovasc. j. 2015; 7(2): 150-152
Trans-catheter Treatment of Lutembacher Syndrome -A Case Report
Authors: Salam ABM Abdus , Islam SK Ziarat , Hasan Kazi Abul , Azad Saiful Islam , Haque Ataul , Shariar Abdullah , Zakia Naznin Umme , Mita Shahina Akter
Published: February 2015

Lutembacher syndrome is a rare combination of congenital Atrial Septal Defect (ASD) and acquired Rheumatic Mitral Stenosis (MS).It is usually treated by surgical repair with potential risk of cardiopulmonary bypass. With the advancement of interventional methods of treatment it is amenable to nonsurgical transcatheter management. We are reporting a case of Lutembacher syndrome that was successfully treated with percutaneouos Inoue balloon mitral valvuloplasty and device closure of atrial septal defect. DOI: http://dx.doi.org/10.3329/cardio.v7i2.22267 Cardiovasc. j. 2015; 7(2): 162-165
Comprehensive Analysis Suggests Overlapping Expression of Rice ONAC Transcription Factors in Abiotic and Biotic Stress Responses
Authors: Sun Lijun , Huang Lei , Hong Yongbo , Zhang Huijuan , Song Fengming , Li Dayong
Published: February 2015

NAC (NAM/ATAF/CUC) transcription factors comprise a large plant-specific gene family that contains more than 149 members in rice. Extensive studies have revealed that NAC transcription factors not only play important roles in plant growth and development, but also have functions in regulation of responses to biotic and abiotic stresses. However, biological functions for most of the members in the NAC family remain unknown. In this study, microarray data analyses revealed that a total of 63 ONAC genes exhibited overlapping expression patterns in rice under various abiotic (salt, drought, and cold) and biotic (infection by fungal, bacterial, viral pathogens, and parasitic plants) stresses. Thirty-eight ONAC genes exhibited overlapping expression in response to any two abiotic stresses, among which 16 of 30 selected ONAC genes were upregulated in response to exogenous ABA. Sixty-five ONAC genes showed overlapping expression patterns in response to any two biotic stresses. Results from the present study suggested that members of the ONAC genes with overlapping expression pattern may have pleiotropic biological functions in regulation of defense response against different abiotic and biotic stresses, which provide clues for further functional analysis of the ONAC genes in stress tolerance and pathogen resistance.
Interfacial Layer Engineering for Performance Enhancement in Polymer Solar Cells
Authors: Zeng Hao , Zhu Xucheng , Liang Yongye , Guo Xugang
Published: February 2015

Improving power conversion efficiency and device performance stability is the most critical challenge in polymer solar cells for fulfilling their applications in industry at large scale. Various methodologies have been developed for realizing this goal, among them interfacial layer engineering has shown great success, which can optimize the electrical contacts between active layers and electrodes and lead to enhanced charge transport and collection. Interfacial layers also show profound impacts on light absorption and optical distribution of solar irradiation in the active layer and film morphology of the subsequently deposited active layer due to the accompanied surface energy change. Interfacial layer engineering enables the use of high work function metal electrodes without sacrificing device performance, which in combination with the favored kinetic barriers against water and oxygen penetration leads to polymer solar cells with enhanced performance stability. This review provides an overview of the recent progress of different types of interfacial layer materials, including polymers, small molecules, graphene oxides, fullerene derivatives, and metal oxides. Device performance enhancement of the resulting solar cells will be elucidated and the function and operation mechanism of the interfacial layers will be discussed.
Soil Quality Impacts of Current South American Agricultural Practices
Authors: Wingeyer Ana , Amado Telmo , Pérez-Bidegain Mario , Studdert Guillermo , Varela Carlos , Garcia Fernando , Karlen Douglas
Published: February 2015

Increasing global demand for oil seeds and cereals during the past 50 years has caused an expansion in the cultivated areas and resulted in major soil management and crop production changes throughout Bolivia, Paraguay, Uruguay, Argentina and southern Brazil. Unprecedented adoption of no-tillage as well as improved soil fertility and plant genetics have increased yields, but the use of purchased inputs, monocropping i.e., continuous soybean (Glycine max (L.) Merr.), and marginal land cultivation have also increased. These changes have significantly altered the global food and feed supply role of these countries, but they have also resulted in various levels of soil degradation through wind and water erosion, soil compaction, soil organic matter (SOM) depletion, and nutrient losses. Sustainability is dependent upon local interactions between soil, climate, landscape characteristics, and production systems. This review examines the region’s current soil and crop conditions and summarizes several research studies designed to reduce or prevent soil degradation. Although the region has both environmental and soil resources that can sustain current agricultural production levels, increasing population, greater urbanization, and more available income will continue to increase the pressure on South American croplands. A better understanding of regional soil differences and quantifying potential consequences of current production practices on various soil resources is needed to ensure that scientific, educational, and regulatory programs result in land management recommendations that support intensification of agriculture without additional soil degradation or other unintended environmental consequences.
DXD Motif-Dependent and -Independent Effects of the Chlamydia trachomatis Cytotoxin CT166
Authors: Bothe Miriam , Dutow Pavel , Pich Andreas , Genth Harald , Klos Andreas
Published: February 2015

The Gram-negative, intracellular bacterium Chlamydia trachomatis causes acute and chronic urogenital tract infection, potentially leading to infertility and ectopic pregnancy. The only partially characterized cytotoxin CT166 of serovar D exhibits a DXD motif, which is important for the enzymatic activity of many bacterial and mammalian type A glycosyltransferases, leading to the hypothesis that CT166 possess glycosyltransferase activity. CT166-expressing HeLa cells exhibit actin reorganization, including cell rounding, which has been attributed to the inhibition of the Rho-GTPases Rac/Cdc42. Exploiting the glycosylation-sensitive Ras(27H5) antibody, we here show that CT166 induces an epitope change in Ras, resulting in inhibited ERK and PI3K signaling and delayed cell cycle progression. Consistent with the hypothesis that these effects strictly depend on the DXD motif, CT166 with the mutated DXD motif causes neither Ras-ERK inhibition nor delayed cell cycle progression. In contrast, CT166 with the mutated DXD motif is still capable of inhibiting cell migration, suggesting that CT166 with the mutated DXD motif cannot be regarded as inactive in any case. Taken together, CT166 affects various fundamental cellular processes, strongly suggesting its importance for the intracellular survival of chlamydia.