bluuebunny/crossref_metadata_2025 huggingface dataset:
The Difficulties of Measuring the Water Saturation and Porosity of Snow
Authors: Colbeck S. C.
Published: September 2017

Liquid saturation and porosity control most of the important material properties of wet snow, hence accurate measurements of these two parameters is of the utmost importance for both field research and glaciological applications. For example, the movement of liquid water through snow is highly sensitive to the volume of water present and accurate measurements of the water saturation are necessary in order to infer the temporal and spatial variations in the flow field. Nevertheless, most of the instruments in use are not capable of making accurate determinations of saturation.

An error analysis shows that only direct measurements of the liquid volume can provide accurate values of water saturation, hence the melting calorimeter is inherently inaccurate. While centrifuges extract some of the liquid for direct measurement, there is always some residual liquid left depending on the grain size and structural parameters of the ice matrix. Therefore, some uncertainty exists over the interpretation of the data obtained from centrifuges. High-frequency capacitance probes can be used either in situ or on the surface and are very sensitive to the volume of liquid present. Capacitance probes are by far the best of the available devices. Remote-sensing techniques, like the active microwave system, require more development for use in operational forecasting schemes and as research tools.
A Recording Snow Lysimeter
Authors: Herrmann A.
Published: September 2017

An instrument which continuously records the run-off from a small, well-defined snow cover is described. The lysimeter is reasonably priced and effective, requiring only modest service attention; details of the records which it takes are given also. The relevance of the instrument to snow hydrology and to the energetics of a snow-cover is discussed.
Polar Firn Densification and Grain Growth
Authors: Alley Richard B. , Bolzan John F. , Whillans Ian M.
Published: September 2017

A 50 m firn core from Dome C, East Antarctica, was found to consist of coarse firn, which comprised 90 to 95% of the core, and fine firn. Coarse firn was characterized by large crystals with a vertical shape orientation near the surface, connected to nearest neighbors by relatively large necks in a structure different from closest packing. Fine firn was of higher density and consisted of smaller, more spherical crystals connected by relatively narrow necks in a more nearly closest-packed configuration.

Higher surface free energy in fine firn causes crystals and necks to grow more rapidly than in coarse firn. However, we find that coarse firn densifies more rapidly with time, contrary to the predictions of unconfined sintering models. Load-driven densification due to a power-law creep mechanism is found to account for the larger coarse-firn densification rate. However, if the exponent in the power law exceeds one, then densification rates are predicted to increase with depth due to increasing load, contrary to observed behavior. We speculate that different mechanisms may control the densification process in fine and coarse firn.
Late Glacial Input of Eolian Continental Dust in the Dome C Ice Core: Additional Evidence from Individual Microparticle Analysis
Authors: Briat M. , Royer A. , Petit J. R. , Lorius C.
Published: September 2017

399 individual microparticles in nine samples from the Dome C ice core were studied under scanning electron microscope and analysed by an energy dispersive X-ray system. The studied particles were either continental quartz or various silico-aluminates of continental or volcanic origin. Observations lead to the conclusion that the increase in micro particle concentration by a factor of 10 to 20 during the last glacial stage is explained by a large input of continental dust, as already indicated by trace element analysis (Petit and others 1981) and previously suggested by chemical analysis of other polar ice cores (Cragin and others 1977).This increase is considered to be a consequence of the ice-age climate and earth surface conditions which were characterized by the increase of arid regions and more vigorous atmospheric circulation. Both these conclusions are further supported by the existence of a higher quartz content in the Antarctic ice core as was already found in tropical deep-sea core studies.
Possible Causes of the Variation in Microparticle Concentration in an Ice Core from Mizuho Station, Antarctica
Authors: Fujii Yoshiyuki , Ohata Tetsuo
Published: September 2017

Variation of the microparticle concentration in an ice core from Mizuho station, East Antarctica, does not show the annual cycle that has been demonstrated for ice cores from Antarctica and Greenland by other authors. Possible reasons for the lack of a annual cycle are considered and two causes are suggested. (1) Semi-annual variation of microparticle concentration as observed in drift-snow. The low particle concentration in March and in August to October is not due to minor particle transport, but to the dilution of microparticles transported mainly from arid regions in the southern hemisphere through the troposphere by falling snow. (2) Discontinuous surface-layer formation. A seasonal or an annual sequence of the variation in microparticle concentration in surface snow layers may be interrupted by the absence of surface snow-layer formation.
Microparticle Analysis of the Ross Ice Shelf Q-13 Core and Preliminary Results From THE J-9CORE
Authors: Mosley-Thompson Ellen , Thompson Lonnie G.
Published: September 2017

The concentration and size distribution of microparticles are measured on the Ross Ice Shelf at three sites: Q-13, base camp, and J-9. Results from the analysis of 2 611 samples representing the 100 m core from site Q-13 are presented. Increasing particle concentrations since 1800 are interpreted as a reflection of the gradual movement of the Q-13 drill site northward toward the Ross Sea under greater influence of the dissipating cyclonic storms in the Ross embayment. A substantial increase in particle concentrations found between 1920–40 may reflect an increase in the frequency and/or intensity of cyclonic storms dissipating in the Ross Sea. This is under investigation. Preliminary microparticle analyses of a small portion of each of 39 sections from the 416 m J-9 core indicate a substantial increase in particle concentrations between 250 and 350 m, possibly signaling the presence of late glacial, or Wisconsin, ice
Present-Day Glaciation in the South Shetland Islands
Authors: Orheim Olav , Govorukha L.S.
Published: September 2017

This paper presents mass-balance results from Deception Island for 1968–69 to 1973–74, from King George Island for the balance years 1969–70 and 1970–71, and from Livingston Island from 1971–72 to 1973–74.

The accumulation areas of all localities are in the soaked fades, with a firn/ice transition at King George Island at 12 to 20 m depth. Of the glaciers studied, only “Gl” on Deception Island terminates wholly on land and has a relatively large ablation area.

The mass-balance curves are similar for King George Island and Livingston Island, with equilibrium lines at around 150 m elevation. “Gl“ on Deception Island has more negative summer balances, and the equilibrium line ranged from 275 to 370 m during the six balance years. Here, there were no years of positive net mass balance, and large negative net values during the 1970–71 to 1972–73 balance years. This resulted from a lowered albedo caused by ash from the August 1970 eruption. Ash layers from the Deception Island eruptions are also observed on Livingston Island and King George Island, where they form stratigraphic markers in the accumulation areas of the glaciers.

Annual balance variations from 1957–58 to 1970–71, based on stratigraphic studies at Deception Island and King George Island, show good correlations, indicating that the variations reflect changes in regional climate.
Dynamic behaviour of rutford ice stream
Authors: Stephenson S.N , Doake C.S.M
Published: September 2017

The grounding-line region of Rutford Ice Stream was surveyed from the ground during 1978–79 and 1979–80, and from the air in 1980–81. Maps of surface elevation and ice thickness of an area of 1 000 km2 allow the grounding line to be delineated and show that the ice stream consists of several distinct fingers of thick ice trending parallel to the flow. In one area, the floating ice is more than 2 000 m thick. Hydrostatic tiltmeters were used to pinpoint the grounding line. Repeated survey of a network of stakes gave velocity and strain-rates for both longitudinal and transverse profiles. Radio echo-fading pattern studies showed the ice to be completely sliding near the grounding line. Modelling of the ice stream, using steady-state theory, shows that the bottom melting rate is around 1.8 m a−1. The small surface and bottom gradients imply that the position of the grounding line may be sensitive to small changes in ice thickness.
Spatial Distribution of Microparticles Within Antarctic Snow-Fall
Authors: Thompson Lonnie G. , Thompson Ellen Mosley
Published: September 2017

The concentration and size distribution of water insoluble microparticles were measured in 2 332 snow and firn samples from (a) two sites on the Antarctic Peninsula, (b) the Byrd station strain network, West Antarctica, (c) the Q-13 and base camp sites on the Ross Ice Shelf, and (d) the South Pole and Dome C sites in East Antarctica. These near-surface microparticle studies indicate that, while the number of particles per unit volume of sample remains fairly uniform from site to site, the annual particle accumulation is greatest at locations nearest the coast and decreases rapidly with distance inland. The relationship between particle accumulation and distance from the coast is analogous to a relationship between snow accumulation and distance from the coast. Ten times more particles are deposited annually at stations within 50 km of the coast than at the South Pole and Dome C sites. The size distribution data reveal that, with the possible exception of the Q-13 site, the particulates deposited in Antarctica are well-sorted, indicating little contribution from local sources.
Anomalous Behaviour of Antarctic ice Cores Studied by Electrical and Mechanical Damping Measurements
Authors: Vassoille R. , Perez J. , Tatibouet J. , Duval P. , Maccagnan M.
Published: September 2017

In order to obtain new information concerning the anomalous properties of Antarctic ice previously observed through electrical measurements, we have studied specimens from a coastal site by means of internal friction measurements in the 1 Hz range. The results have been compared to previous ones obtained with polar ice from Dome C and electrical measurements have been made on the same samples in order to confirm the anomalous behaviour of such material.

Two possible explanations of the anomalous properties of polar ice are discussed, namely the role of impurities and the ageing effect. It seems improbable that impurities could be responsible for such properties due to their low concentration. Some experiments, however, lead us to interpret the behaviour of polar ice in terms of modifications with time of the concentration and distribution of intrinsic point defects present at the beginning of the existence of the ice microcrystals
Radio Echo-Sounding Of Shirase Glacier And The Yamato Mountains Area
Authors: Wada Makoto , Yamanouchi Takashi , Mae Shinji
Published: September 2017

In 1979, the National Institute of Polar Research (NIPR) developed a 179 MHz airborne radio echo-sounder (NIPR-A), and installed it in a Pilatus Porter PC-6 aircraft. The peak power of the sounder is about lkW and the pulse width is 0.3 ys. Soundings were carried out in Antarctica on Shirase Glacier and the Yamato Mountains in January 1980. The total flight distance over the Shirase Glacier was about 500 km in six flights, while, on the Yamato Mountains area, about 80 km long, two north-south flights and three eastwest flights were carried out.

In spite of poor wave penetration, the presence of many sub-glacial uplands (1 000 to 2 000 m a.s.l.) near the Yamato Mountains area was revealed. Discussion is concentrated on the bedrock and surface topography of the bare ice area near Motoi Nunatak in the southeast Yamato Mountains, because the previous traverse party covered this area and many meteorites have been discovered here.

A high sub-ice ridge with three peaks extends east of Motoi Nunatak, and from 22 to 28 km east of Motoi Nunatak there is a short ridge with two peaks. From 12 to 20 km up-glacier from Motoi Nunatak, a long but comparatively low ridge surrounds Motoi Nunatak ridge like an arc. Finally, the sub-ice flow lines near Motoi Nunatak are deduced from new and earlier data.
Glacier Fluctuations in George VI Sound Area, West Antarctica (Abstract only)
Authors: Clapperton C.M. , Sugden D.E.
Published: September 2017

George VI Sound lies between Alexander Island and the Antarctic Peninsula and is over 20 km wide and 500 km long. At present an ice shelf fills the sound and is nourished largely by ice from the Antarctic Peninsula which flows across the sound to ground against the coast of Alexander Island. Ice-free areas, comprising small nunataks and larger massifs, fringe both sides of the sound and contain evidence of the former glacial history of the area. This paper describes the field evidence in detail and uses geomorphological and sedimentary analyses to put forward a relative glacial chronology, constrained by two absolute dates.

The chronology distinguishes:

(1) a maximum state during which all ice-free areas were submerged by ice flowing into George VI Sound from both the Antarctic Peninsula and Alexander Island and thence along the sound as an ice stream. This occurred in the late Wisconsin and followed an interstadial or interglacial when George VI Sound was free of an ice shelf.

(2) a valley-based stadial during overall deglaciation represented by pronounced marginal moraines on Alexander Island.

(3) deglaciation to a stage where there was less landbased ice on Alexander Island than today. At this stage isostatic recovery was incomplete, relative sealevel was higher, and George VI Ice Shelf penetrated further into embayments on Alexander Island than at present.

(4) probable disappearance of George VI Ice Shelf by 6.5 14C ka BP.

(5) neoglacial readvance of local glaciers on Alexander Island to form three closely spaced terminal moraines and the growth of a new George VI Ice Shelf which was again more extensive than at present.

(6) subsequent oscillations of both smaller Alexander Island glaciers and George VI Ice Shelf probably during the Little Ice Age. These fluctuations are similar to those in other sub-Antarctic Islands in the Scotia Sea and also in southern Chile.
Ice Flow Along AN Iagp Flow Line, Wilkes Land, Antarctica (Abstract only)
Authors: Young N.W. , SheehY D. , Hamley T.
Published: September 2017

Trilateration and single line surveys have been made to about 900 km inland of Casey, Wilkes Land, to measure surface elevation, ice thickness, horizontal velocity, and other parameters. On the large scale the velocity U increases smoothly from 8 m a−1, 800 km inland, to 280 m a−1 inland of the fast outlet streams. This increase in velocity is associated with a corresponding increase in the large-scale smoothed (over about 30 ice thicknesses) basal shear stress τb from 0.4 to 1.5 bar. The mean shear strain-rate through the ice sheet U/Z = kτb4, where Z is the ice thickness (range 4 500 to 1 700 m).

At scales of one to several ice thicknesses large variations occur in surface slope and ice thickness without proportionally large velocity variations, because of the effect of the longitudinal stress. Detailed measurements made over a 30 km section indicated that the surface longitudinal strain-rate gradient varied from -1.7 to +1.3×l0−6 a−1 m−1 along with variations in surface slope of from -3.5 to +1.5%.

A multilayer model, based on the solution of the biharmonic equation for the stream function, was used in a study of the ice flow associated with these surface undulations. Given the bedrock topography and large-scale flow parameters, the model closely predicted the measured surface profile when the variation of the surface accumulation rate over an undulation was also considered.
Some Evidence of Long-Distance Transport, Local Sources and Fractionation Between Air and Snow for Metallic Aerosols Deposited in Antarctic Snows Since the 1880s (Abstract only)
Authors: Buat-Menard P , Boutron C
Published: September 2017

Using instrumental neutron activation analysis, we have determined the concentrations of Na, CI, Al, Sc, V, Cr, Mn, Co, Fe, Zn, As, Se, Br, Sb, and J in ultra-clean dated snow samples collected in central East Antarctica. These samples had been previously analysed by flameless atomic absorption spectrometry (Boutron 1980). For the elements determined by both techniques (Na, Al, Mn, Fe, and Zn) the results are in remarkable agreement. These new data confirm and extend the conclusion that background concentrations of trace elements observed at present in Antarctic snow are close to those observed about 100 a BP and thus that Antarctic aerosol is still little affected by global atmospheric pollution. These data also confirm that, for several metals, episodes of anomalously high concentrations are in phase with increased sulphate and acidity, which could result from volcanic fallout. However, during such episodes, a straightforward relationship between the rate of increase in trace metals and the rate of increase in sulphate and acidity is not observed. This also affects volatile elements such as Cl, Br, Se, and I. This is probably due to a combined effect of local versus long-range transport of volcanic aerosols together with a physico-chemical segregation between the various components of this aerosol.
Analysis Of Interannual Changes In Antarctic Sea-Ice Cover Using Passive Microwave Observations (Abstract only)
Authors: Zwally H.J. , Comiso J.C. , Parkinson C.L. , Carsey F.D. , Campbell W.J. , Gloersen P.
Published: September 2017

A quantitative comparison of seasonal and interannual Antarctic sea-ice coverage over the four years 1973-76 has been accomplished through the use of passive microwave imagery from the Nimbus-5 satellite. For the entire Southern Ocean both the total ice extent (area with ice concentration greater than 15%) and the actual ice area (the spatially-integrated ice concentration) have decreased over this period of 4 a, but not uniformly in all regions. From 1973 to 1976 the annual-mean value of total ice extent decreased from 13.8 × 106 km2 to 12.1 × 106 km2, yielding an average decrease of 4.0% a−1. The inter-annual difference is greatest during the spring, as the ice decays, with the decrease in the December-mean averaging 8.4% a−1, the largest of any month. The decrease in the November-mean averaged 4.5% a−1. The overall decrease was principally due to the consistent yearly decrease of ice In the Weddell Sea sector (60°W to 20°E). Other sectors show less consistency. For instance, the ice in the Ross Sea sector (130°W to 160°E) increased from 1973 to 1974 and then decreased from 1974 to 1976, and no consistent trend is apparent in the ice extent between 20°E and 160°E. The total ice extent in the Bellingshausen- Amundsen seas sector (60°W to 130°W) actually increased slightly from 1973 to 1976. The area of the open water within the ice pack behaved differently from the total ice area, Increasing each year from February to November but having no clear interannual trend. A detailed analysis of the passive microwave imagery for the Antarctic region is planned for publication in an atlas.
Estimation of Precipitation and Accumulation for the Iagp Area from Rawinsonde Data (Abstract only)
Authors: Bromwich D.H.
Published: September 2017

Routine upper-air observations for the year 1972 are used to construct the atmospheric water vapor budget between the coast and the line joining the highest points of the terrain between the meridians 55°E and 110°E. This gives seasonal and annual values of precipitation for an area of 2.4 × 106 km2. Annual accumulation amounts are then estimated for the whole budget region. By assuming that the accumulation poleward of the 2 000 m elevation contour equals the 1972 precipitation, the annual areallyaveraged precipitation (and thus the accumulation) is computed for the coastal slopes below 2 000 m.

Rigorous analysis of the rawinsonde data from five coastal stations and one on the plateau is a feature of this study. A special attempt is made to resolve the key boundary-layer properties. A systematic and important bias in the record due to missed observations during storms is demonstrated. The use of estimates for these missing values, which are obtained from multilinear regression equations, increases the computed annual poleward water-vapor transport at two stations by more than 30%.

Regions of net water-vapor inflow to and outflow from the continent were found to be organized in the same fashion as the mean circulation in the lower troposphere: the budget region is under the influence of a cyclonic vortex centered offshore. There was a poleward-directed, integrated (surface to 300 mbar) eddy flux of water vapor at all points along the coast. 43% of the annual precipitation fell during the period June to August due to a particularly stormy sequence mainly at one station.

The annual accumulation between the coast and the crest of the terrain is estimated with an uncertainty of 17%, and for the coastal slopes with an uncertainty of 39%. Comparison of the multiannually averaged accumulation derived from glaciological measurements with the computed values for a single year shows agreement within the limits of error.

In conclusion, the water-vapor budget approach produces accumulation values similar to the glaciological measurements. This approach offers a viable alternative method for monitoring the seasonal and annual accumulation over large parts of East Antarctica.
A Turbulent Mixture Theory for the Atmospheric Mixture of Snow and Air
Authors: Decker Rand , Brown R. L.
Published: September 2017

A theory based on classical fluid mechanics for an incompressible, chemically non-reacting, atmospheric mixture of air and entrained snow particles is derived. These continuum equations of motion are then expanded to include turbulent flow. The reduced, one-dimensional equations of this theory are further refined by order-of-magnitude analysis and correlation of the turbulent terms to mean flou parameters. The resulting one-dimensional, turbulent equations of motion for the snow contain apparent turbulent forces which enhance entrainment of snow where gradients of the air flow are high. These turbulent equations of motion are then solved numerically for snow particle velocity and concentration as a function of height above the surface. The results are similar to observed profiles of snow concentration and the superposition of the solution of this turbulent mixture theory for snow entrainment with an appropriate solution for the saltation layer will eventually lead to a working continuum theory for blowing snow.
Laboratory Experiments on Crystal Orientation in NaCl Ice
Authors: Langhorne Patricia J.
Published: September 2017

Over extensive areas of the Arctic and Antarctic, the c-axes of the grains in a sea-ice sheet develop a preferred orientation in a particular direction in the Horizontal plane, causing the physical and electromagnetic properties of the material to be anisotropic. A number of mechanisms have been proposed for this alignment, the more likely including the tilting of floes, horizontal temperature gradient, horizontal deviatone stresses, and oceanic currents. Laboratory experiments have been performed at the Scott Polar Research Institute to distinguish the effects of these mechanisms on the fabric of sea ice. Ho correlation was found between the development of the preferred orientation of c-axes and any of the first three mechanisms. However, in the presence of a current, the strength of the alignment increases rapidly with depth in the ice, the mean c-axis direction coinciding with the current direction. A significant reduction in alignment was produced when the flow was reduced to zero. In addition, upstream deflection of the columnar axis was observed in flowing brine. These results indicate the importance of fluid motion in controlling the rate of transport of solute from the interface and hence the relative growth rates of grains of different orientations.
Recycling of Sulfuric Acid in the Valorization of Biomass Residues
Authors: Havasi Dávid , Pátzay György , Stelén Gábor , Tukacs József M. , Mika László T.
Published: September 2017

The biomass-based production of levulinic acid requires aqueous mineral acid as catalyst. In the present study, the possible reuse of sulfuric acid in the biomass conversion was investigated. The acid can either be reused after extracting the product or before extraction. The results show that both methods are applicable for producing levulinic acid while reducing the sulfuric acid demand of the process. Conversion of D-fructose showed similar results after five recycle steps in both post- and pre-extraction methods. The post-extraction method was successfully repeated four times with cooked tea leaves. The sulfuric acid applied for the conversion of a simulated household waste was successfully recycled eight times with pre-extraction plus once by post-extraction without significant change in the product formation.
Medical Management of Stable Angina: Systematic Therapeutic Approach
Authors: Mahmood Manzoor , Hoque Harisul
Published: September 2017

Abstract not availableUniversity Heart Journal Vol. 12, No. 1, January 2016; 1
Short Term Clinical Outcome in Patients with Mitral Valve Replacement with or without Preservation of Subvalvular Apparatus
Authors: Husain Sabrina Sharmeen , Ahmed Chaudhury Meshkat , Mohmmad Sohan Arif , Mahmud Sohel , Rahman Md Mustafizur , Zaman SM Mustafa , Khaled Md Fakhrul Islam , Osmany DMMF
Published: September 2017

Background: Preservation of subvalvular apparatus (SAP) during mitral valve replacement (MVR) was introduced about forty years back, but the outcome of this procedure is not well studied yet. Our study aimed to measure the in-hospital outcome of this procedure in rheumatic patients.Method: 44 patients of rheumatic heart disease undergoing for MVR in the department of cardiac surgery, BSMMU were enrolled for the study. The technique of SAP was according to choice of surgeon. Patients were divided into two groups- I) with preservation: complete preservation, where entire chordo-papillary apparatus was preserved & partial preservation, where posterior leaflet was preserved, II) no preservation: where subvalvular apparatus was completely excised. Surgical technique was different according to patients requirement and one of either technique was adopted by Fuster et al or Miki et al. Patients demographic profile and mitral valve status were recorded. Outcome was recorded in terms of hemoynamic outcome and in hospital death. Data was analyzed by Chi squired test.Result: Mean±SD of age of patients was 32±8 years, 29±7years in group-I, 36±9years in group-II. There was no significant difference in age distribution between two groups. Both groups were female predominant, 82% in group-I and 73% in group-II. Low cardiac output syndrome was observed in 4.5% of group-I and 32% in group-II (P-value was <0.001). Left ventricular failure was observed as 0% & 32% respectively (p value was <0.001). Inotropic agent was needed 45% & 75% respectively (p value was <0.01). In hospital death occurred in 4.5% & 13.5% in two groups respectively with no significant difference.Conclusion: Hemodynamic outcome and in hospital mortality was better when subvalvular apparatus was preserved during mitral valve replacement in rheumatic population.University Heart Journal Vol. 12, No. 1, January 2016; 3-7
Prognostic value of serum Uric Acid in-hospital Mortality and Morbidity in Patients with acute Myocardial Infarction
Authors: Hossain Md Deldar , Ferdousi Sheuly , Islam Md Saiful , Paul Debatosh , Sultana Ttuhin , Hoque Harisul , Rahman Md Quddusur , Banerjee Sajal Krishna , Ahmed Annashimuddin
Published: September 2017

Coronary artery disease (CAD) is one of the leading causes of death in the world and also in Bangladesh. This study was carried out to evaluate that Serum uric acid is a prognostic tool in acute myocardial infarction. In this study, 108 AMI cases were enrolled. All the patients were treated and managed identically by conventional standard management protocol. During hospital stay, patients were assessed for any kind of clinical outcomes e.g good recovery, mortality and morbidity (acute LVF, cardiogenic shock, arrhythmia and heart block). Patients with higher serum uric acid (SUA>6.5mg%, Group-II) were compared with Patients with lower serum uric acid (SUA<6.5mg%, Group-I). In Group I (n=66), good recovery, morbidity and mortality were found in 43 (65.2%), 21 (31.8%), 2(3.0%) patients and in Group II (n=42), good recovery, morbidity, mortality were 13 (31%), 23 (54.8%) and 6 (14.3%) patients respectively. In group II patients having high Serum uric acid concentration had low good recovery but high morbidity and mortality compared to group I patients. In group I (n=66), good outcome and bad outcome was found in 43(65.2%), and 23 (34.8%) patients and in group II (n=42), those were in 13 (31%) and 29 (69%) patents. Logistic regression analysis of serum uric acid concentration of study subjects were done considering uric acid as independent variable but outcome as dependent variable. It was shown that the odds ratio of mortality was 5.38(95% CI p<0.007), odds ratio of morbidity was 4.10(95% CI p<0.001) and odds ratio of bad outcome was 4.67(95% CI p<0.001). This findings indicates a patient having high uric acid had 5.38 times increased mortality, 4.10 times increased morbidity and 4.67 times increased bad outcome than patients having low serum uric acid concentration.University Heart Journal Vol. 12, No. 1, January 2016; 8-11
Incidence of Malignancy Related Pericardial Effusion in a Tertiary Hospital
Authors: Fatema Nilufar , Rahman Wahidur , Samdani Tasrina Shamnaz , Rahman M Asadur , Rahman Afsana , Siddiqua Ayesha , Aziz Ahmed Monjurul , Sultan Md Ashraf Uddin , Sharmin Farzana , Arzu Jahanara
Published: September 2017

Back ground: Malignancy related pericardial effusion (PE) may represent a terminal event in patients with therapeutically unresponsive disease. Pericardial tamponade (PT) is a co morbid condition in many diagnosed malignant cases. Selection of patients with malignancies who are responsive to available treatment may achieve significant improvement in palliation. Early detection of pericardial tamponade and appropriate intervention (Pericardiocentesis) or Subxyphoid pericardiotomy may result long term survival benefit.Objective: Early detection and management of PE and tamponade in malignant cases.Methods: Color Doppler (C-D) echocardiography was done in 260 patients with underlying malignancies on chemo or radiotherapy from oncology department of Delta Medical college and hospital from May 2016 to December 2016. These cases were reviewed retrospectively for clinical features, diagnosis and therapy for their malignancy.Results: 81% have shortness of breath, sign of pulsus paradoxus and pericardial tamponade were found in 22% and 5% patients respectively. During echocardiography, pericardial effusion was found in 102 patients. 65% have mild pericardial effusion, whereas 27% have moderate and 8% have severe PE. Effusions with malignancy comprising of 40% adenocarcinomas of lung, 15% carcinoma (Ca) of pharynx, 10% Ca breast, 10% lymphoma, 10% is Carcinoma of unknown primary, 8% Ca esophagus and 7% others (Renal, Hepatic, ovary & cheek).University Heart Journal Vol. 12, No. 1, January 2016; 23-25
Effect of Ticagrerol versus Clopidogrel on Oxidative Stress Bio-markers in Patients with Chronic Stable Angina after Percutaneous Coronary Intervention
Authors: Sharmin Elora , Dewan Jasmine Fauzia , Ahsan Syed Ali , Hoque Harisul , Ahmed Sheikh Foyez , Sultan Md Ashraf Uddin , Bhuiyan Habiba Akhter , Bhadra Shima , Barua Chaity
Published: September 2017

Background: Ischemic heart disease remains the leading cause of death in both developed and under developed countries. The use of antiplatelet drugs specifically the thienopyridine has become a standard for the treatment of acute coronary syndrome. These drugs irreversibly inhibit the platelet aggregation by blocking the P2Y12 receptor. But currently this therapeutic choice has become limited due to potential interaction with other drugs, slow hepatic conversion, genetic resistance and narrow therapeutic safety margin. Ticagrerol, a reversible P2Y12 receptor inhibitor may represent a significant advancement over currently available oral antiplatelet drugs.Objectives: The study was intended to compare the effect of Ticagrelor and Clopidogrel on oxidative stress markers in patients of chronic stable angina (CSA) following percutaneous coronary intervention (PCI).Materials & Methods: The present prospective observational study was carried out in the Department of Pharmacology, Cardiology and Microbiology, BSMMU, Dhaka from September 2014 to February 2016. The study included a total of 100 CSA patients. Patients were divided into two groups, Ticagrelor and Clopidogrel treated groups (each having 50 patients). The baseline laboratory parameters-Malondihyde (MDA), Reduced glutathione (GSH), bleeding time, clotting time and platelet count, were measured and then patients of both groups underwent PCI. The same parameters were again assessed at follow up after 4 weeks of intervention. Total 12 patients from Ticagrelor and 14 patients from Clopidogrel groups were dropped out. Comparisons of the laboratory parameters were made between two groups at baseline and at follow up and also within group before and after intervention.Result: In the present study at baseline characteristics of patients treated with ticagrelor and clopidogrel were almost identical in terms of age, sex, diabetes and hypertension. The level of plasma MDA in ticagrelor group was significantly reduced from baseline to follow up(4.5 ± 1.8 to 1.4 ± 0.7, p <0.001) and in clopidogrel group (4.2 ± 1.2 to 1.3 ± 0.7, p <0.001). GSH level was increased from 0.7 mg/dl to 2.5 mg/dl (p <0.001) in ticagrerol group and in clopidogrel group 0.6 mg/dl to 1.4 mg/dl, p <0.001).Conclusion: The study concluded that both ticagrelor and clopidogrel are similar effect on oxidative stress markers, resulting from oxidative injury processes in patients of chronic stable angina.University Heart Journal Vol. 12, No. 1, January 2016; 26-30
Pulmonary Arterial Hypertension Associated With Congenital Heart Disease
Authors: Sheikh Naveen
Published: September 2017

The management of patients with congenital heart disease (CHD) and pulmonary arterial hypertension (PAH) has changed dramatically with the development of targeted therapy with selective pulmonary vasodilators. It is important to develop evidence-based guidelines for the management of these patients, and to achieve this, a register of adult Bangladeshi patients with PAH associated with CHD should be established. At the World Symposium in Nice, France, in 2013, the consensus was reached that patients with a pulmonary resistance of < 4 Wood Units (WU)û0m2 have operable disease, and patients with a pulmonary resistanceof > 8 WUû0m2 have inoperable disease. However, these criteria are conservative. Some patients with a pulmonary resistance of > 8 WUû0m2 and a good response to a pulmonary vasodilator test have operable disease and a favorable clinical course long after repair of CHD. The criteria determining operability in patients with PAH associated with CHD in the era of pulmonary vasodilators should be established using data obtained from patient registers and/or multicenter studies. The optimal management of Eisenmenger syndrome should also be established using data obtained from patient registers. Prospective studies should be conducted to determine the life expectancy of patients with Eisenmenger syndrome in the era of targeted therapy. A relatively mild increase in pulmonary resistance may result in failure of a Fontan circulation. The effects of pulmonary vasodilators on the long-term prognosis of patients who have undergone the Fontan operation are still unclear. (Int Heart J 2015; 56: S1-S3).University Heart Journal Vol. 12, No. 1, January 2016; 31-33
Surgical Management of Ebsteins Anomaly with Atrial Septal Defect in a Young Lady: A Case Report
Authors: Rahman CM Mosabber , Alam SM Rakibul , Sunny Samir Azam , Adhikary Asit Baran
Published: September 2017

Ebsteins anomaly is a rare congenital heart defect accounting for <1% of all cases. It is commonly associated with other cardiac malformations particularly, 50% of the patients are associated with atrial septal defect. We report a 22-year-old lady diagnosed to have Ebsteins anomaly with small atrial septal defect. She was surgically managed in Bangabandhu Sheikh Mujib Medical University by replacing the defective tricuspid valve withSt Jude Medical Epic porcine bio-prosthetic heart valve along with plication of atrialized portion of right ventricle and direct closure of the atrial septal defect.This resulted in excellent symptomatic improvement.University Heart Journal Vol. 12, No. 1, January 2016; 37-39
Pulmonary Embolism - A Case Report
Authors: Nahar Samsun , Momenuzzaman - , Begum Fatema , Khan KN , Anisuzzaman Quazi , Dhar Razib
Published: September 2017

PE remains a clinically challenging diagnosis, more often missed than found, with no decline in its incidental discovery at autopsy over the past 30 years. Pulmonary embolism should be considered in the differential diagnosis of every dyspnoea event that presents at an emergency department. We describe a case of 68 years old man with symptoms of dyspnoea who later diagnosed as pulmonary embolism. This case report emphasizes early diagnosis and treatment to avoid fatal outcome.University Heart Journal Vol. 12, No. 1, January 2016; 40-44
Prosthetic Valve Endocarditis: A Case Report
Authors: Huque AKM Ziaul , Khan Omar Sadeque , Shah Sanjeet Kumar , Aftabuddin Md , Adhikary Asit Baran , Morshed Nahid Mahjabin
Published: September 2017

Prosthetic valve endocarditis(PVE) is the most serious complications of valve replacement. Despite improvements in medical treatment and surgery, prosthetic valve endocarditis carries a high mortality. The best treatment strategy for these patients is still debated. Although a surgical strategy is said to be the best treatment option, some authors claim that medical treatment can be sufficient for some patients. Here we presented two cases of prosthetic valve endocarditis where both the patients were treated conservatively using multiple antibiotics. One patient improved within a short period of time, while another patient expired.University Heart Journal Vol. 12, No. 1, January 2016; 45-48
Primary Antiphospholipid syndrome presenting with acute ST elevated MI with normal coronaries
Authors: Islam Lohani Md Tajul , Chowdhury Abdul Wadud , Rahman AKM Fazlur , Sultana Sarjana , Osmany DMM F , Hasan Md Nazmul
Published: September 2017

Myocardial infarction (MI) under the age of 40 years accounts for around 3% of cases of coronary artery disease. Coronary artery atherosclerosis is less commonly the underlying aetiology in this age group and more comprehensive investigation of the cause is required. Antiphospholipid syndrome is a rare cause for MI which can be found younger age group. Here,We report a22 years young patients with MI who had normal coronary arteries on coronary angiogram that proved to have primary APS.University Heart Journal Vol. 12, No. 1, January 2016; 49-50
Prof. M Aftabuddin
Authors: Editor -
Published: September 2017

Abstract not availableUniversity Heart Journal Vol. 12, No. 1, January 2016; 55
Prof. Dr. Md. Abu Siddique
Authors: Editor -
Published: September 2017

Abstract not availableUniversity Heart Journal Vol. 12, No. 1, January 2016; 56
Editorial: Guided-Wave Optics
Authors: Malomed Boris
Published: September 2017

Guided waves represent a vast class of phenomena in which the propagation of collective excitations in various media is steered in required directions by fixed (or, sometimes, reconfigurable) conduits [...]
Size and Shape Controlled Crystallization of Hemoglobin for Advanced Crystallography
Authors: Sato-Tomita Ayana , Shibayama Naoya
Published: September 2017

While high-throughput screening for protein crystallization conditions have rapidly evolved in the last few decades, it is also becoming increasingly necessary for the control of crystal size and shape as increasing diversity of protein crystallographic experiments. For example, X-ray crystallography (XRC) combined with photoexcitation and/or spectrophotometry requires optically thin but well diffracting crystals. By contrast, large-volume crystals are needed for weak signal experiments, such as neutron crystallography (NC) or recently developed X-ray fluorescent holography (XFH). In this article, we present, using hemoglobin as an example protein, some techniques for obtaining the crystals of controlled size, shape, and adequate quality. Furthermore, we describe a few case studies of applications of the optimized hemoglobin crystals for implementing the above mentioned crystallographic experiments, providing some hints and tips for the further progress of advanced protein crystallography.
Environmental Influences on Maternal and Child Health
Authors: Theall Katherine , Johnson Carolyn
Published: September 2017

This Special Issue of IJERPH focuses on maternal and child health (MCH), with research that highlights the role of environmental influences on MCH across a range of settings.[...]
Ambient Air Pollution and Risk for Ischemic Stroke: A Short-Term Exposure Assessment in South China
Authors: Guo Pi , Wang Yulin , Feng Wenru , Wu Jiagang , Fu Chuanxi , Deng Hai , Huang Jun , Wang Li , Zheng Murui , Liu Huazhang
Published: September 2017

Data on the association between air pollution and risk of ischemic stroke in China are still limited. This study aimed to investigate the association between short-term exposure to ambient air pollution and risk of ischemic strokes in Guangzhou, the most densely-populated city in south China, using a large-scale multicenter database of stroke hospital admissions. Daily counts of ischemic stroke admissions over the study years 2013–2015 were obtained from the Guangzhou Cardiovascular and Cerebrovascular Disease Event Surveillance System. Daily particulate matter <2.5 μm in diameter (PM2.5), sulfur dioxide (SO2), nitrogen dioxide (NO2), ozone (O3), and meteorological data were collected. The associations between air pollutants and hospital admissions for stroke were examined using relative risks (RRs) and their corresponding 95% confidence intervals (CIs) based on time-series Poisson regression models, adjusting for temperature, public holiday, day of week, and temporal trends in stroke. Ischemic stroke admissions increased from 27,532 to 35,279 through 2013 to 2015, increasing by 28.14%. Parameter estimates for NO2 exposure were robust regardless of the model used. The association between same-day NO2 (RR = 1.0509, 95% CI: 1.0353–1.0668) exposure and stroke risk was significant when accounting for other air pollutants, day of the week, public holidays, temperature, and temporal trends in stroke events. Overall, we observed a borderline significant association between NO2 exposure modeled as an averaged lag effect and ischemic stroke risk. This study provides data on air pollution exposures and stroke risk, and contributes to better planning of clinical services and emergency contingency response for stroke.
Effect of Distortion on Turbofan Tonal Noise at Cutback with Hybrid Methods
Authors: Daroukh Majd , Moreau Stéphane , Gourdain Nicolas , Boussuge Jean-François , Sensiau Claude
Published: September 2017

New ultra high bypass ratio architectures may significantly affect the fan tonal noise of future aircraft engines. Indeed, such a noise source is supposed to be dominated by the interaction of fan-blade wakes with outlet guide vanes. However, shorter nacelles in these engines are expected to trigger an important air-inlet distortion that can be responsible for new acoustic sources on the fan blades. Full annulus simulations based on the unsteady Reynolds-averaged Navier–Stokes equations are presently used to study this effect. Simulation results show that the air-inlet distortion has a main effect in the fan-tip region, leading to a strong variation of the fan-blade unsteady loading. It also significantly modifies the shape of the fan-blade wakes and, consequently, the unsteady loading of the outlet guide vanes. Acoustic predictions based on the extension of Goldstein’s analogy to an annular duct in a uniform axial flow are presented and show that the fan sources notably contribute to the fan tonal noise. The air-inlet distortion is responsible for an increase of the noise radiated by both the fan and the outlet guide vane sources, leading to a global noise penalty of up to three decibels.
Ultra-Low Power, Process-Tolerant 10T (PT10T) SRAM with Improved Read/Write Ability for Internet of Things (IoT) Applications
Authors: Singh Pooran , Vishvakarma Santosh
Published: September 2017

In this paper, an ultra-low power (ULP) 10T static random access memory (SRAM) is presented for Internet of Things (IoT) applications, which operates at sub-threshold voltage. The proposed SRAM has the tendency to operate at low supply voltages with high static and dynamic noise margins. The IoT application requires battery-enabled low leakage memory architecture in a subthreshold regime. Therefore, to improve leakage power consumption and provide better cell stability, a power-gated robust 10T SRAM is presented in this paper. The proposed cell uses a power-gated p-MOS transistor to reduce the leakage power or static power in standby mode. Moreover, due to the stacking of n-MOS transistors in 10T SRAM latch and by separating the read path from the 10T SRAM latch, the static and dynamic noise margins in read and write operations has shown significant tolerance w.r.t. the variations in device process, voltage, and temperature (PVT) values. The proposed SRAM shows significantly improved performance in terms of leakage power, read static noise margin (RSNM), write static noise margin (WSNM), write ability or write trip point (WTP), read–write energy, and dynamic read margin (DRM). Furthermore, these parameters of the proposed cell are observed at 8-Kilo bit (Kb) SRAM and compared with existing SRAM architectures. From the Monte Carlo simulation results, it is observed that the leakage power of a proposed low threshold voltage-LVT 10T SRAM is reduced by 98.76%, 98.6%, 6.7%, and 98.2% as compared to the LVT C6T, RD8T, LP9T, and ST10T SRAM, respectively, at 0.3V VDD. Additionally, in the proposed 10T SRAM, parameters such as RSNM, WSNM, WTP, and DRM are improved by 3×, 2×, 1.11×, and 1.32×, respectively, as compared to C6T SRAM. Similarly, the proposed 10T SRAM shows an improvement of 1.48×, 1.25×, and 1.1× in RSNM, WSNM, and WTP, respectively, in the parameters as compared to RD8T SRAM at 0.3 V VDD.