bluuebunny/crossref_metadata_2025_split huggingface dataset:
Liner Materials Exposed To Toxic and Hazardous Wastes
Authors: Haxo H.E. , Haxo Robert S. , Nelson Nancy A. , Haxo Paul D. , White Richard M. , Dakessian Suren 
Published: January 2008

A research project was undertaken to assess the relative effectiveness and durability of a wide variety of liner materials when exposed to hazardous wastes under conditions simulating various aspects of service in waste storage and disposal facilities. The materials studied included compacted soil, admixes, sprayed-on asphalt and 32 polymeric membranes. Four partially crystalline polymeric sheetings, though not compounded for use as liners, were included in the study because of their known chemical resistance and their use in applications requiring good chemical and ageing resistance. The lining materials were exposed in test cells to 10 hazardous wastes (two acidic, two alkaline, three oil, a blend of lead, a pesticide and a briny industrial waste) and three media of known composition—deionized water, 5% aqueous solution of salt and a saturated solution of low-concentration (0.1%) tributyl phosphate. The polymeric materials were also exposed to wastes or environmental conditions under a variety of conditions that included primary one-sided exposure, immersion testing, two types of outdoor exposure and a pouch test. Some of the exposures were as long as 2700 days. New methods for testing polymeric materials are presented. Results indicated that some of the liner materials performed satisfactorily in contact with certain wastes but, because waste combinations can be highly specific, compatibility testing is needed to select a liner for a given waste.
The Use of Industrial Sludges as Raw Materials in the Cement Industry
Authors: Riganti V. , Fiumara A. , Odobez G.B. 
Published: January 2008

Sludge arising from physico-chemical treatment of industrial waste waters can be used as a component of clinker meals in cement plants. The material on which the present experimental work is focused was obtained from industrial sludge poor in organic matter and rich in aluminium, iron and heavy-metal hydroxides. The metals are rendered inert by cement-based binders in full compliance with the current Italian provisions. The material was checked to verify that its components comply with the acceptability limits established by the users, and to assess the level of pollution produced at the processing site. The eluate obtained with CO2-treated water from the treated material does not show appreciable release of heavy-metals. Emission values at the chimney of the cement plant depend on the effectiveness of the gas filtering system. The addition of treated industrial sludge to kiln feed does not have an appreciable effect on the cement-plant chimney dust, and reduces operating cost, without affecting the properties of the product (clinker) and the plant's operating stability.
Performance Appraisal in North Carolina Municipalities
Authors: Daley Dennis 
Published: January 2008

This study surveys performance appraisal practices, focusing upon North Carolina municipal governments. General appraisal procedures involving performance standards, specific types of performance appraisal systems, add-on practices (designed to enhance appraisal effectiveness), and the various purposes underlying appraisals are examined. In addition, the effects of city and organizational size and that of governmental structure on these personnel practices are studied. In general, performance appraisal practices are little used among North Carolina's municipal governments. Under a third claim generic procedures, and a sixth do not have any specific system. Among add-on options only interviews and interim appraisals garner use in as much as a quarter of the towns. Purposes fare somewhat better, with nearly half using performance appraisal as a guide for merit pay decisions. For the most part, performance appraisal is but marginally used in aiding personnel decisions. Population and workforce effects are somewhat in evidence among the Tarheel towns. Larger communities and organizations are slightly more likely to engage in these practices. However, a somewhat more clear cut case can be made with regard to professional managers. While the employment of a town manager is not a sufficient condition, it may be a necessary one if performance appraisal practices are to be properly employed.
Fire Retardant Wood-Fiber Insulating Board
Authors: Östman Birgit A-L. 
Published: January 2008

Two types of fire retardant insulating wood-fiber boards have been developed in laboratory and mill scale. Both include treatments which are incorporated in the normal wet process for manufacturing such boards with a concentration of the fire retardant to one side of the board. One type involves addition of a calcium borate mineral, colemanite, to the top fiber layer of the board. Scandinavian class II and British class 1 are achieved. The other type involves addition of a pre-condensate of melamine-dicyandiamide-phosphoric acid mixed with a commercial phosporus-nitrogen compound on the wet lap. Scandinavian class I and British class 1 are achieved. The first type, colemanite, creates no problem in normal board production or in respect to product properties. It is readily suited to full scale application. The second type has a better fire classification but is accompanied by production and product problems, e.g. mildew growth at humid exposure, and needs further development. Both board types have been exposed in ceiling application for 8 years without any reduction in fire classification.
The Lane County Survey: An Episode in the Development of Rural Planning
Authors: Hibbard Michael 
Published: January 2008

One of the major social concerns at the turn of the twentieth century—how best to cope with massive urbanization and industrialization—stimulated the rise of modern American urban and regional planning. Most of those active in the nascent field of planning directed their efforts toward the receiving end of the population shift, the cities. But the changes in rural places, and especially the meaning of rural change for society as a whole, also received much attention. A variety of activities sprang up in the 1910s and '20s in an effort to strengthen rural institutions. In this article I focus on one category of those activities, the rural survey. The surveys are an important precursor to current approaches to rural socio-economic development planning: they highlight the key roles that culture and community play in the development process. I first describe the perceived situation in rural America at the turn of the century. Next I discuss the development of the rural survey as a method to diagnose rural problems. I then examine one example of a rural survey, that done in Lane County, Oregon, in 1915 and '16. Finally, I consider the legacy of rural surveys—their impact on the development of planning for rural areas.
Introduction to the Series
Authors: Sarnat Harvey B. 
Published: January 2008

The accompanying article, "How to construct a neural tube," is the first in a new series. This series is designed to present new data on ontogeny and molecular genetic programming in terms meaningful to practicing clinicians who treat children with neurologic diseases. This new series, entitled The New Neuroembryology, is about development. Development is a term that to the neuroscientist represents a well-programmed sequence of anatomic and physiologic changes that occur from conception to maturity. Many clinicians, however, use the same term in reference to the functional acquisition of skills, and a whole discipline, developmental pediatrics, has evolved in this context. Both uses are correct— related but different. The New Neuroembryology is about molecular genetic programming of the nervous system, induction, trophic factors, cellular proliferation, apoptosis, adhesion molecules, migrations, intercellular communication, and substrates of cellular differentiation and maturation: normal and abnormal. Breakthroughs in biologic science that change forever our understanding of primordial life processes are rare events, despite the misperceptions and hyperbole of the popular media. A fountainhead of new molecular genetic information on embryonic and fetal development has erupted in the past decade and even the most skeptical and cautious scientist would concede that it does represent a conceptual breakthrough. The new concepts disclosed are inspiring not only in terms of depth of understanding, but also in their promise of new approaches to diagnosis and perhaps even treatment that were not even wildly speculated just a few years ago. These new data explain ontogeny as histology has never done to elucidate the pathogenesis and mechanisms of malformations of the nervous system. The Journal of Child Neurology proudly acknowledges this conceptual revolution in our chosen specialty as we enter a new decade and introduce pediatric neurology into a new millennium.
Restoring Cardiac Function: An Emerging Spectrum of Therapeutic Options
Authors: Kantrowitz Adrian 
Published: January 2008

A spectrum of techniques for restoring cardiac function is emerging. Among patients with global congestive heart failure (CHF), cardiac transplantation may help a small minority for whom allografts are available; the total artificial heart may eventually benefit a larger number. For patients with left-sided CHF, parallel-assist techniques maximally augment cardiac output. In-series techniques can help others without major arrhythmias and some residual cardiac output. As compared with parallel assist, in-series methods offer lesser hemodynamic augmentation but greater intrinsic reliability and the possibility of deactivation of support for hours or days without increased risk. Additional advantages include simplicity of management and documented long-term clinical efficacy.
Thermedics' Approach to Ventricular Support Systems
Authors: Szycher M. , Clay W. , Gernes D. , Sherman C. 
Published: January 2008

Temporary and permanent ventricular assist systems, developed by Thermedics, Inc., are described, including rationale, design, operation and surgical applications. Clinical data are presented for pneumatically driven temporary left ventricular assist devices (LVAD). Usefulness of this device rests on the assumption that tissue of a weakened heart can recover if relieved for a time by an LVAD. The surgical implantation of an LVAD is reported in a case where the patient later received a heart transplant. The concept and technology of the subsystems of a permanent ventricular assist system (VAS), now ready for preclinical trials, are discussed. Design of a low-speed, torque-motor driven blood pump is described. Details are presented on transcutaneous energy transmission by means of a transformer, one of whose coils is embedded under the skin. Though less efficient than percutaneous transmission, the method eliminates infection risk. Special types of polyurethanes are analyzed in respect to their biocompatibility. It is concluded that flocking of the polyurethane surface allows the growth of a biological lining which is highly antithrombogenic. Sintered metal powders are found to be most efficient for fabrication of rigid pump components. A lenticular pump design is proposed to solve the problem of pressure differentials in the sealed device. Cardiac endocrine functions are cited in support of using assist devices that leave the heart in place.
Societal and Ethical Considerations of Artificial Hearts
Authors: Paquin Michael 
Published: January 2008

The present state of artificial heart research and development is analyzed in light of public perceptions affected by accounts of the experiences of those who received the Jarvik-7. On the assumption that research will continue, it is argued that the therapeutic goals of the artificial heart can be realized, and funding be obtained, only in an atmosphere of positive publicity. To this end, formation of an association of companies involved in artificial heart R & D is recommended. Such a group would articulate voluntary standards and produce reports of advances in the field. Artificial hearts, it is noted in conclusion, have been effective as temporary assist devices in patients destined to receive heart transplants.
Softening of Thermoplastic Polyurethanes: A Structure/Property Study
Authors: Zdrahala Richard J. , Spielvogel David E. , Strand Marc A. 
Published: January 2008

Softening of thermoplastic polyurethanes (TPU) in a simulated body environment (37°C n-saline) was studied as a function of composition, structure and resultant morphology of these ( AB) n type block copolymers. The structural variations were attempted by changing chemical composition and molecular weight of both hard A and soft B segments and their weight ratio in the polymer. In addition, the influence of bulk and/or surface modifiers, such as "reacted-in" polysiloxanes and fluorinated polyalkylether glycols, was also investigated. The degree of softening, expressed as a percentage decrease of the elastic modulus (5% tensile modulus) upon two hours exposure to the testing environment, is significant, reversible and depends on the ratio of hard to soft segment and the extent of microphase separation. Since these parameters can be selected during the polymer synthesis and processing into desirable shapes, the degree of softening can thus be controlled. This softening at body temperature represents one of the most notable performance advantages of these biomaterials.
Permeability of PEUU Membranes: Their Modification Towards Blood Compatibility
Authors: Jayasree G. , Sharma Chandra P. 
Published: January 2008

An attempt was made to develop haemodialysis membranes using polyether urethane urea synthesised in our laboratory. It was observed that the processing parameters such as precipitation medium, precipitation temperature etc. can influence the porosity of the membrane and subsequently the permeability property. It was also noted that the permeability of the dried membrane was negligible even though it was kept in distilled water overnight before use. The effect of pH on permeability through the membrane was studied by dialysis experiment using mixtures of various components such as urea, creatinine, uric acid, inulin, albumin, NaCl and KCI at various pH. Standard cellulose acetate (CA) membrane was used for comparison. Membranes were also prepared using biomer solution by precipitating in distilled water at room temperature and the monomer, 2-hydroxy ethyl methacrylate (HEMA) was grafted onto it by glow discharge technique. It was found that the permeability was increased by HEMA grafting with some loss of tensile strength and strain. A comparative study of fibrinogen adsorption during dialysis and adsorption by direct exposure of samples to a mixture containing urea, uric acid, creatinine, dextran, fibrinogen and electrolytes like sodium and potassium ions was also done with 125I labelled fibrinogen. Platelet adhesion studies indicated that the number of adhered platelets was less on the HEMA grafted samples which may enhance blood compatibility. Finally, the membranes were subjected to different sterilization processes possible under wet conditions such as glutaraldehyde treatment and autoclaving. The contact angle, permeability, mechanical property and platelet adhesion studies indicated that the sterilization method can affect the performance of the membrane.
Mechanical Assistance in Cardiogenic Shock
Authors: Moulopoulos Spyridon D. 
Published: January 2008

Cardiogenic shock following myocardial infarction or surgical interventions with extracorporeal circulation, not responding to conventional treatment, is an "intractable" condition, unless mechanical assistance is applied. In today's practice mechanical assistance consists in counterpulsating an intraaortic balloon or, if this does not improve the condition, in using a left ventricle bypassing pump. In spite of the complexity of the procedures and the com. plications, a number of patients can recover with or without a subsequent corrective intervention or heart transplantation. The need for developing systems for chronic assistance to non-correctable hearts and the difficulties of the endeavour are pointed out.
In vivo Testing of a Biostable Polyurethane
Authors: Szycher Michael , Reed Andrew M. , Siciliano Arthur A. 
Published: January 2008

At present all the commercially available "medical grade" urethane elastomers exhibit a phenomenon known as environmental stress cracking (ESC). This phenomenon is characterized by surface microcracking when the elastomer is elongated while in vivo. The degree of strain that is required to initiate microcracking varies from composition to composition. It has been found that harder compounds generally tend to have a higher strain threshold than corresponding softer ones. We theorized that this degradation occurs when certain enzymes (present only in vivo) attack and break down the ether linkages that link the polymer molecules together. Those elastomers that contain more ether linkages (such as the softer compositions) appear to microcrack more easily than elastomers with fewer ether linkages (such as the harder ones). The molecular composition of ChronoFlex™ urethane has been chosen so that the finished elastomer will be free of ether linkages; thus, it is expected to be immune from environmental stress cracking.
Testing Intelligent Wound Dressings
Authors: Palamand Shashi , Reed Andrew M. , Weimann Ludwig J. 
Published: January 2008

While occlusive wound dressings help provide patients with moist wound healing to reduce pain and increase reepithelialization rate, the moisture vapor transmission rate (MVTR) of these dressings remains constant even though wound exudate levels may vary with time and from wound to wound. The clinician is therefore faced with exudate buildup in heavily exuding wounds and desiccation in lightly exuding wounds-a situation requiring frequent patient monitoring and dressing changes. Am "intelligent" wound dressing would have the ability to automatically respond to a wound's exudate level by self-adjusting its MVTR to maintain a constant moist wound environment. Such a dressing could help ensure that exudate buildup or wound desiccation is reduced or avoided. Three commercial wound dressings (hydrocolloid, thin film, and membrane laminate) were studied for their ability to alter their MVTR in response to varying moisture level. An efficient test methodology and experimental design was developed, which involved direct and indirect fluid contact with the dressings using two temperatures and two test methods. One dressing, a membrane laminate, was found to exhibit intelligent MVTR behavior. Data is presented which shows this dressing's ability to adjust its MVTR nearly eight-fold as a function of hydration level. Information regarding the mechanism of action of this intelligent dressing is also presented.
Modern Wound Dressings: A Systematic Approach to Wound Healing
Authors: Szycher Michael , Lee Steven James 
Published: January 2008

The advent of modern wound care management constitutes one of the most innovative applications of medical device technology. The foundation for wound care recent advances has been built upon the developments achieved in polymer technology over the last three decades. New and unique materials have been engineered to provide properties with significant technical and clinical benefits. These new wound care products were made possible by the convergence of three interrelated disciplines: (1) more complete understanding of the underlying principles of dermal wound healing processes, (2) new elastomeric polymers capable of being fabricated into protective dressings, and (3) advances in breathable adhesive technology. The following discussion provides a critical review of the current status of technology and the worldwide opportunities for improved wound management products. Particular attention is focused on the clinical applications of the newer, breathable dressing products, which approximate a temporary synthetic artificial skin.
Drape Analysis using Imaging Techniques
Authors: Robson Dean , Long Christina C. 
Published: January 2008

Many textile properties have traditionally been assessed using subjective methods dependent upon one or more of the human senses. It is generally accepted that these methods can be unreliable, and the development of more reliable and consistent objective measurement systems is a key objective for textile scientists. In this study, the application of an imaging system to the detailed objective measurement of the drape profiles of a range of wool fabrics, captured from a traditional drape tester, is investigated. Image processing and analysis software techniques are successfully implemented to enable, by the measurement of a number of key parameters, a full and automatic characterisation of the drape profiles reflecting visual impression. Drape coefficient values gathered via the instrumental technique correlate strongly with those established using the traditional cut and weigh approach. Strong parameter relationships are identified, and it is established that a three parameter combination of drape coefficient, number of nodes and variation in node severity would be required to enable good discrimination between the drape profiles of the fabric range under study.
Efficacy of Four Cleaning Solutions in Removing Smoke Damage From Apparel Fabrics
Authors: McLellan Cloud Rinn , Bondurant Lynn A. , Keith Nancy K. 
Published: January 2008

A study was conducted to determine the efficacy of selected cleaning solutions in removing visible and odorous smoke damage from dress-weight apparel fabrics of 100% polyester, 65/35% polyester/cotton, 50/50% polyester/cotton, and 100% cotton. The cleaning solutions tested involved the use of a powder detergent, a liquid detergent, a powder detergent combined with liquid bleach, and a dry-cleaning solution. The use of liquid detergent or powder detergent combined with chlorine bleach successfully removed visible and odorous smoke damage from the fabrics tested. Powder detergent and dry cleaning were the least effective in removing visible smoke damage but successfully removed odor damage. The results suggested home methods of smoke damage removal may be useful for consumers for which other methods are ineffective or unavailable.
Perceived Importance of Selected Skills to a . Group of Discount Store Buyers
Authors: Kean Rita C. 
Published: January 2008

Attention towards continuing professional development has been cited as a means of improving motivation and performance of retail store buyers. This study assessed the perceived importance of selected skills to a group of discount store buyers, using education, experience and store volume as variables. Opportunities for skill development by their employers were also examined. Fifty-seven buyers (41 %) from discount chain stores within the United States responded to a mailed questionnaire. Most were 3 1 to 45 years old, had attended college, had seven to fifteen years experience, and were employed by retail organizations whose sales volume was between $1,000,000.00 and $500,000,000.00. Results indicated even though the discount store buyers felt the use and development of selected skills highly important, minimal opportunity existed within the retail organization for skill development. Recommendations were made to stores to implement more training opportunities in order to provide development of skills the buyers deemed important.