bluuebunny/crossref_metadata_2025_split huggingface dataset:
The behaviour of prestressed concrete portal frames as influenced by creep and temperature
Authors: Krishnamoorthy S. , England G. L. , Yu C. W. 
Published: July 2012

Synopsis This paper describes experiments staged to observe the long-term effects of creep upon the behaviour of axially prestressed, two-pinned portal frames subjected to long-sustained elevated temperature regimes. The test apparatus is described and experimental results are presented. It is concluded that non-uniform temperatures significantly affect the deflection behaviour of the structures and cause internal stresses and moments to undergo marked changes with time. Elastic theory is incapable a;j'estimating these changes. Other theories which recognize creep are therefore necessary.
The shear strength of uniformly loaded beams without web reinforcement
Authors: Ojha S. K. 
Published: July 2012

Synopsis This paper describes an iterative method of calculating the failure load of uniformly loaded reinforced concrete rectangular beams without shear reinforcement. Use is made of basic equations, derived in an earlier paper. By utilizing the “distortion energy principle”, it has been possible for the first time to predict the section of failure mathematically, and so also the inclination of the shear crack. In developing a failure criterion for the concrete of the compression zone, due weight has been given to the vertical stresses due to loading. The calculated results show fairly good agreement with experimental evidence.
Effects of lateral reinforcement upon the strength and deformation properties of concrete
Authors: Sargin M. , Ghosh S. K. , Handa V. K. 
Published: July 2012

Synopsis Confinement of concrete by rectilinear lateral reinforcement is discussed. An experimental investigation is described in which the main variables were: concrete strength; size, spacing and grade of lateral reinforcement; strain gradient; and thickness of cover. In the analysis of test results, laterally reinforced specimens are treated as composite members consisting of core and cover. The parameters of an analytical stress-strain relationship, which was found to describe the mechanical properties of plain and laterally reinforced concrete adequately, are determined from a regression analysis of the test results. The experimental results are compared with the strength of confined concrete as predicted by (1) a formula based on a theoretical analysis, and (2) an equation which unifies several previously proposed formulae giving the strength of laterally reinforced concrete.
An apparatus for curing to a predetermined time-temperature function
Authors: Bell F. H. 
Published: July 2012

Synopsis An automatically controlled water-curing apparatus has been designed and built at a cost for materials of $400. It can be programmed to follow predetermined time-temperature curves between 8 and 60°C to within ± 1°C, and tests with the tank unloaded have shown that, in a heating period, a temperature change from 8 to 60°C can be achieved in 7 hours. In a cooling period, the temperature can be reduced from 60 to 8°C in 55 hours.
The effect of moisture content upon the elasticity of hardened cement paste
Authors: Parrott L. J. 
Published: July 2012

Synopsis Data on the effect of moisture content upon the axial and lateral elastic compliances of hardened cement pastes with a range of porosities are presented. A number of explanations for the results are examined including one which postulates that calcium silicate hydrate can dehydrate at high humidities. The dehydration mechanism is consistent with the author's results and might help to explain data by other investigators on bulk modulus, shrinkage and sorption behaviour of hardened cement paste.
The effect of different test procedures upon the indicated strength of concrete blocks in compression
Authors: Roberts J. J. 
Published: July 2012

Synopsis Although the use of loose fibre-board caps with single blocks may increase the variation within a set of results when compared with mortar capping, the amount will depend largely upon the skill and experience of the mortar-capping operative. From an economic viewpoint, the board-capped single block specimen offers several advantages, and the sample size may be adjusted to give the required level of accuracy to the determination of block strength. The relationship between the results of tests on mortar- and board-capped specimens may be calculated, and both forms of test related directly to the performance of concrete block work walls.
Methods of measuring the air and water permeability of concrete
Authors: Figg J. W. 
Published: July 2012

Synopsis This paper describes simple and portable apparatus for estimating the air and water permeability of concrete in situ. The methods used require a small hole 5·5 mm diameter and 30 mm deep to be drilled in the specimen. The hole is plugged with a catalysed liquid silicone rubber which sets to give a resilient seal to the small cavity in the concrete. A gas- and liquid-tight connection is obtained by inserting a hypodermic needle through the silicone ruhber. The results obtained using the apparatus on laboratory-prepared concrete show good correlation with both water/cement ratio and compressive strength; it is suggested that the proposed methods may prove useful for predicting the durability of concrete. The techniques are sensitive enough to detect differences in aggregate porosity. The moisture content of the concrete has a major injiuence on the readings; a miniaturized moisture meter is being developed so that corrections can be made for this effect.
A method for determining the shear strength of reinforced concrete beams with small av/d ratios
Authors: Desayi Prakash 
Published: July 2012

Synopsis Some of the limitations of the methods available for determining the ultimate strength of reinforced concrete beams with a < av/d < 1·0 are discussed in the light of the results of an experimental programme. A method for determining the shear strength of such beams is presented which takes into account the splitting strength of concrete and the influence of any steel crossing the failure crack. The nominal ultimate shear stress calculated by the proposed method is found to be comparable with a total of 161 test results on concrete and plaster of Paris beams reported in the literature, including tests by the author on reinforced concrete beams without web reinforcement.
Free and bound water in cement pastes
Authors: Harris D. H. C. , Windsor C. G. , Lawrence C. D. 
Published: July 2012

Synopsis Quasi-elastic neutron scattering has been used to investigate the nature of the bonding of water molecules in cement pastes of various porosities. The experiments show that it is possible, to quite a good approximation, to speak of the water as being either ‘bound’ with negligible mobility, or ‘free’ with the full mobility of bulk water. There is no evidence for any hydration state of intermediate mobility. The ratio offree to total water in saturated specimens given by these experiments is considerably less than that obtained from conventional weight-loss measurements under controlled drying.
Uniaxial tensile creep and failure of concrete
Authors: Domone P. L. 
Published: July 2012

Synopsis This paper describes a series of experiments carried out on concrete under uniaxial tensile stress, using a test method developed previously. The properties assessed include the effect of mix proportions and curing conditions upon the short-term failure stress and strain and upon the tensile creep under a load of 35% of the ultimate short-term strength. The effect of variable humidity states upon the tensile creep was also investigated, and the results interpreted from the viewpoint of creep hypotheses for compressive loading. Where possible, the observed effects are related to the microstructure of cement gel. Finally, the effects upon creep of the level of loading and of the long-term strength of concrete in tension have been determined, and compared with the established behaviour in compression.
The prediction of crack widths in reinforced concrete beams
Authors: Albandar F. A-A. , Mills G. M. 
Published: July 2012

Synopsis Two parameters, concrete cover and average effective area of concrete surrounding each bar, were varied in a factorial experiment on rectangular reinforced concrete beams. Crack widths were measured from full-scale photographic plates taken of the tensile region for the series of nine beams loaded to a selected steel stress. Comparisons are made between the observed mean and maximum crack widths, predicted values from previously suggested formulae, and a new formula proposed by the authors which incorporates the two parameters varied together with the average concrete strain at the level considered.
The strip method of slab design: unique or lower-bound solutions?
Authors: Fernando J. S. , Kemp K. O. 
Published: July 2012

Synopsis The yield conditions in moment fields produced by the strip method of slab design are examined and rules are derived for yield lines in a collapse mechanism to be consistent with the unique solution. It appears that the strip method does not always produce a unique solution for the collapse load, but the exceptions are rare.
Some experimental studies on a reinforced concrete slab-beam system
Authors: Datta T. K. , Ramesh C. K. 
Published: July 2012

Synopsis Experimental tests on nineteen single-panel square slab-beam models are reported in order to study the enhancement of the load-carrying capacity due to the development of compressive membrane forces. The variables included are the percentage of reinforcement, and the degree of edge restraint at the surrounds of the slab provided by the varying lateral rigidity of the edge beams. The ultimate loads of the models are predicted by a method proposed by the authors and compared with the experimentally obtained values for good agreement. An empirical recommendation for the enhanced capacity due to T-beam action alone, which induces some precompression in the slab, is also made.
Shear strength of prestressed concrete beams without web reinforcement
Authors: Mahgoub M. O. 
Published: July 2012

Synopsis This paper represents a detailed study, based on dimensional analysis, of the factors which seem to affect the shear strength of prestressed concrete beams under one- or two-point loading. Fifty-eight pre-tensioned concrete beams of seven different cross-sections were tested. The load at the first inclined tension crack rather than the ultimate load is taken to limit the capacity of these beams in shear because of the indeterminate factors involved in calculating the latter. An expression for predicting this inclined cracking load is derived and compared, for specific cases, with other published expressions. Other published test results are in a good agreement with the derived expression.
Influence of binary aggregate proportions upon some concrete properties
Authors: Nwokoye Daniel N. 
Published: July 2012

Synopsis The paper reports work continuing two earlier researches and exploiting further the use of ultrasonic-pulse-velocity tests to examine the internal structure of concrete and its influence upon certain physical and mechanical properties. It is found that binary aggregate proportions affect (a) the relationships between paste pulse velocity and cube strength and (b) the dynamic elastic moduli of cement paste; mortar, quasi-mortar {cement paste plus coarse aggregate) and concrete phases and also have some influence upon the workability of concrete. For the particular mixes tested, the maximum dynamic modulus, maximum concrete pulse velocity and the maximum loose and rodded bulk densities of the combined aggregates all occurred at the optimum coarse-aggregate content for workability. The test further confirmed that, in predicting the elastic modulus of concrete, the elastic modulus of the quasimortar merits as much consideration as that of the mortar itself. The curves for both moduli due to changes in the volume fraction of sand and coarse aggregates intersect at a point influenced by the age of the concrete
Ice thickness, areal and volumetric changes of Davies Dome and Whisky Glacier (James Ross Island, Antarctic Peninsula) in 1979–2006
Authors: Engel Zbynĕk , Nývlt Daniel , Láska Kamil 
Published: July 2012

AbstractThis study calculates area, volume and elevation changes of two glaciers on James Ross Island, Antarctica, during the period 1979-2006. Davies Dome is a small ice cap. Whisky Glacier is a valley glacier. Ground-penetrating radar surveys indicate ice thickness, which was used for calculations of the bed topography and volume of both glaciers. Maximum measured ice thicknesses of Davies Dome and Whisky Glacier are 83 ± 2 and 157 ± 2 m, respectively. Between 1979 and 2006, the area of the ice cap decreased from 6.23 ± 0.05 km2 to 4.94 ± 0.01 km2 (-20.7%), while the area of the valley glacier reduced from 2.69 ± 0.02 km2 to 2.40 ± 0.01 km2 (-10.6%). Over the same period the volume of the ice cap and valley glacier reduced from 0.23 ± 0.03 km3 to 0.16 ± 0.02 km3 (-30.4%) and from 0.27 ± 0.02 km3 to 0.24 ± 0.01 km3 (-10.6%), respectively. The mean surface elevation decreased by 8.5±2.8 and 10.1 ±2.8m. The average areal (~0.048-0.011 km2a-1) and volumetric (~0.003−0.001 km3 a-1) changes are higher than the majority of other estimates from Antarctic Peninsula glaciers.
Mass-balance parameters derived from a synthetic network of mass-balance glaciers
Authors: Machguth Horst , Haeberli Wilfried , Paul Frank 
Published: July 2012

AbstractGlacier mass-balance parameters such as the equilibrium-line altitude (ELA) play an important role when working with large glacier samples. While the number of observational mass-balance series to derive such parameters is limited, more and more modeled data are becoming available.Here we explore the possibilities of analyzing such 'synthetic' mass-balance data with respect to mass-balance parameters. A simplified energy-balance model is driven by bias-corrected regional climate model output to model mass-balance distributions for 94 glaciers in the Swiss Alps over 15 years. The modeling results in realistic interannual variability and mean cumulative mass balance. Subsequently model output is analyzed with respect to 18 topographic and mass-balance parameters and a correlation analysis is performed. Well-known correlations such as for ELA and median elevation are confirmed from the synthetic data. Furthermore, previously unreported parameter relationships are found such as a correlation of the balance rate at the tongue with the accumulation-area ratio (AAR) and of the glacier elevation range with the AAR. Analyzing modeled data complements in situ observations and highlights their importance: the small number of accurate mass-balance observations available for validation is a major challenge for the presented approach.
Prevalence and Risk Factors of Metallo β-lactamase Producing Pseudomonas aeruginosa and Acinetobacter species in Burns and Surgical Wards in a Tertiary Care Hospital
Authors: Kumar Simit H , De Anuradha S , Baveja Sujata M , Gore Madhuri A 
Published: July 2012

ABSTRACT
Introduction: The production of Metallo-β-lactamases (MBLs) is one of the resistance mechanisms of Pseudomonas aeruginosa and Acinetobacter species. There is not much Indian data on the prevalence of MBLs in burns and surgical wards.
Materials and Methods: A total of 145 non-duplicate isolates of carbapenem-resistant Pseudomonas aeruginosa and Acinetobacter species, isolated from pus/wound swabs and endotracheal secretions from burns and surgical wards, were tested for MBL production by modified ethylene diamine tetra acetic acid (EDTA) disc synergy and double disc synergy tests.
Results: Prevalence of MBLs was 26.9% by both the above tests. All MBL-positive isolates were multidrug resistant. Only 6.06% (2/33) P.aeruginosa and 16.67% (1/06) Acinetobacter species were susceptible to piperacillin-tazobactam and netilmycin, respectively. These patients had multiple risk factors like >8 days hospital stay, catheterization, IV lines, previous antibiotic use, mechanical ventilation, etc. Graft application and surgical intervention were significant risk factors in MBL-positive patients. Overall mortality in MBL-positive patients was 34.21%.
Conclusion: Emergence of MBL-producing Pseudomonas aeruginosa and Acinetobacter species in this hospital is alarming, which reflect excessive use of carbapenems and at the same time, pose a therapeutic challenge to clinicians as well as to microbiologists. Therefore, a strict antibiotic policy and implementation of proper infection control practices will go a long way to prevent further spread of MBLs. Detection of MBLs should also become mandatory in all hospitals.
Ophthalmomyiasis Externa Caused by Oestrus ovis
Authors: Shankar Mahesh Kumar , Diddapur Seethalakshmi Krishnamurthy , Nadagir Shobha Dhruv , Kota Subramanya Giliyar 
Published: July 2012

ABSTRACTA 50-year-old male presented with foreign body sensation, pain, and redness in left eye. Slit-lamp biomicroscopy revealed tiny larvae crawling around the conjunctival sac. The larvae, numbering 13, were mechanically removed under topical anesthesia and identified under light microscope as first-stage larvae of Oestrus ovis causing ophthalmomyiasis externa.
Primary Pulmonary Sporotrichosis in a Sub-Himalayan Patient
Authors: Singhai Monil , Rawat Vinita , Verma Pankaj , Jha Pawan Kumar , Shree Divya , Goyal Rajeev ,   Umesh
Published: July 2012

ABSTRACTPrimary pulmonary sporotrichosis, a rare fungal disease was found in chronic alcoholic farmer from the sub-Himalayan region, an endemic mycoses area. Primary pulmonary sporotrichosis is a hidden entity, at times mimicking tuberculosis, and often under or lately diagnosed due to lack of awareness. We should consider the possibility of pulmonary sporotrichosis in patients with chronic cough and cavitary parenchymal disease, particularly in chronic alcoholics, gardeners, and forest workers. Sputum culture for fungus as a part of diagnostic studies is needed especially in endemic mycoses areas for early detection and management of such fungal diseases.
Reducing Donor Site Morbidity When Reconstructing the Nipple Using a Composite Nipple Graft
Authors: Lee Taik Jong , Noh Hyung Joo , Kim Eun Key , Eom Jin Sup 
Published: July 2012

Background Numerous procedures are available for nipple reconstruction without a single gold standard. This study presents a method for reducing donor-site morbidity in nipple reconstruction using a composite nipple graft after transverse rectus abdominis musculocutaneous flap breast reconstruction.
Methods Thirty-five patients who underwent nipple reconstruction using a composite nipple graft technique between July of 2001 and December of 2009 were enrolled in this study. To reduce the donor site morbidity, the superior or superior-medial half dome harvesting technique was applied preserving the lateral cutaneous branch of the fourth intercostal nerves. The patients were asked to complete a previously validated survey to rate the color and projection of both nipples, along with the sensation and contractility of the donor nipple; and whether, in retrospect, they would undergo the procedure again. To compare projection, we performed a retrospective chart review of all the identifiable patients who underwent nipple reconstruction using the modified top hat flap technique by the same surgeon and during the same period.
Results Thirty-five patients were identified who underwent nipple reconstruction using a composite nipple graft. Of those, 29 patients (82.9%) responded to the survey. Overall, we received favorable responses to the donor site morbidity. Projection at postoperative 6 months and 1 year was compared with the immediate postoperative results, as well as with the results of nipples reconstructed using the modified top hat flap.
Conclusions The technique used to harvest donor tissue is important. Preserving innervation of the nipple while harvesting can reduce donor site morbidity.
A Retrospective Review of Iatrogenic Skin and Soft Tissue Injuries
Authors: Lee Tae Geun , Chung Seum , Chung Yoon Kyu 
Published: July 2012

Background Even though the quality of medical and surgical care has improved remarkably over time, iatrogenic injuries that require surgical treatment including injuries caused by cast and elastic bandage pressure, extravasation, and dopamine-induced ischemia still frequently occur. The goal of this study was to estimate the incidence and analyze the distribution of iatrogenic injuries referred to our department.
Methods A retrospective clinical review was performed from April 2006 to November 2010. In total, 196 patients (116 females and 80 males) were referred to the plastic surgery department for the treatment of iatrogenic injuries. We analyzed the types and anatomic locations of iatrogenic complications, along with therapeutic results.
Results An extravasation injury (65 cases, 37.4%) was the most common iatrogenic complication in our study sample, followed by splint-induced skin ulceration, dopamine-induced necrosis, prefabricated pneumatic walking brace-related wounds and elastic bandage-induced wounds. Among these, prefabricated pneumatic walking brace-related complication incidence increased the most during the 5-year study period.
Conclusions The awareness of the very common iatrogenic complications and its causes may allow physicians to reduce their occurrence and allow for earlier detection and referral to a plastic surgeon. We believe this is the first study to analyze iatrogenic complications referred to a plastic surgery department in a hospital unit.
L’écriture de la vertu
Authors: Sublon Roland 
Published: July 2012

L’a. relit la manière dont Aristote écrit l’éthique, fondement de son projet politique, afin de pointer les ressemblances existant entre la démarche aristotélicienne et la théorisation du sujet par la psychanalyse (lacanienne), et de montrer que l’éthique d’Aristote, loin d’être fermée, principielle et nécessariste, est ouverte à l’incertitude, et donc, très actuelle, puisqu’elle a une structure de topologie moebienne, voire borroméenne. Il existe une assonance entre la manière dont Aristote écrit la vertu, la prudence, la tempérance, le plaisir et l’amitié, et la théorisation de Lacan. Dans un premier temps, l’a. examine la construction de la prudence chez Aristote. Métaphysique θ, 6 fournit une clé de lecture (généralement négligée) de l’Éthique à Nicomaque, grâce aux catégories de puissance et acte, qui permettent de penser la dimension pulsionnelle, insaisissable, de l’agent vivant, irréductible à toute chosification, et par ailleurs doué de parole. Or, puisque les catégories utilisées par Aristote sont déterminées linguistiquement (penser et parler sont indissociables), un rapprochement s’opère avec un opérateur logique de la psychanalyse : la Lettre. Celle-ci rend compte de la structure involutive propre à l’activité du sujet parlant, dans l’articulation de l’identique et du différent. L’éthique n’est-elle pas l’impossible mais nécessaire réconciliation des contraires ? Donc, la puissance de l’éthique s’actualise par la parole, mais la vertu (l’excellence) est indissociable de la prudence. Dans un deuxième temps, l’a. examine la construction de l’amitié chez Aristote. L’agent est-il déterminé dans ces choix par un principe idéal aux effets nécessaristes ? Prenant le contrepoids de l’interprétation commune, menant plus loin son analyse de la prudence et s’appuyant encore une fois sur des parallèles lacaniens, l’a. écarte résolument cette possibilité. L’expérience exige de ne pas séparer πάθος et λόγος ni d’en privilégier l’un au détriment de l’autre. La topologie moebienne de Lacan permet ainsi de penser à nouveau frais, avec Aristote, l’amitié.