Biphasic synthetic bone substitute use in orthopaedic and trauma surgery: clinical, radiological and histological results

Searching for an alternative to bone grafts in orthopedic and trauma surgery, two biphasic synthetic calcium phosphate ceramics BCP are made: the first, Eurocer 400®, in granule form with a high interconnected porosity for void-filling, and the second, Eurocer 200®, available in different shapes, with a good mechanical resistance in compression. Two hundred cases are reported with more than a six-month follow-up. The first 72 cases relating to hip arthroplasty revision surgery (29 involving acetabular and 43 femoral stem loosening) are exposed with some technical details. The next 71 cases concerning trauma and sequels are displayed with technical particulars. The remaining 57 other cold orthopedic indications are then enumerated. The very good biocompatibility of these ceramics is confirmed. Radiological incorporation is quickly seen in all the cases, faster with the filling substitute than with the second one, which, however, presents no mechanical failures when classical technical principles are respected. Finally, some histological studies are presented; the ceramics are progressively resorbed and bone reconstruction in and close to the substitutes is noticed. Therefore, the use of biophasic ceramics in almost all orthopedic and trauma surgery is recommended.     

Vicenza International Courses on hemodialysis: Educational events where science meets clinical practice

International Vicenza Courses represent important educational events held yearly in the city of Palladio. Claudio Ronco organizes since 1982 international courses on peritoneal dialysis, hemodialysis and critical care nephrology. The faculty is outstanding and the content very informative and useful for beginners and for experts in the various fields. Every year the entire course is recorded in a DVD and the proceedings are available at the beginning of the course. Information can be obtained at http://www.vicenzanephrocourses.com .     

The popularization of science: Some basic measurements

Four pairs of articles provide a framework for the bibliometric analysis of presentations of scientific findings to non-specialist audiences. One member of each pair is a professional-level review article; the other is its counterpart as published inScientific American. Two of the pairs were published in the mid-1960's and two pairs were published in the mid-1980's. The pace and scope of popular reportage improved over the twenty-year span but the readability index for popular treatments suggests that there are stil serious barriers to mass audience consumption. Examination of the personal references in the popular presentations reveals linkage patterns that are analogous to those found by citation and co-citation analyses.     

Sumatran megathrust earthquakes: from science to saving lives

Most of the loss of life, property and well-being stemming from the great Sumatran earthquake and tsunami of 2004 could have been avoided and losses from similar future events can be largely prevented. However, achieving this goal requires forging a chain linking basic science-the study of why, when and where these events occur-to people's everyday lives. The intermediate links in this chain are emergency response preparedness, warning capability, education and infrastructural changes. In this article, I first describe our research on the Sumatran subduction zone. This research has allowed us to understand the basis of the earthquake cycle on the Sumatran megathrust and to reconstruct the sequence of great earthquakes that have occurred there in historic and prehistoric times. On the basis of our findings, we expect that one or two more great earthquakes and tsunamis, nearly as devastating as the 2004 event, are to be expected within the next few decades in a region of coastal Sumatra to the south of the zone affected in 2004. I go on to argue that preventing future tragedies does not necessarily involve hugely expensive or high-tech solutions such as the construction of coastal defences or sensor-based tsunami warning systems. More valuable and practical steps include extending the scientific research, educating the at-risk populations as to what to do in the event of a long-lasting earthquake (i.e. one that might be followed by a tsunami), taking simple measures to strengthen buildings against shaking, providing adequate escape routes and helping the residents of the vulnerable low-lying coastal strips to relocate their homes and businesses to land that is higher or farther from the coast. Such steps could save hundreds and thousands of lives in the coastal cities and offshore islands of western Sumatra, and have general applicability to strategies for helping the developing nations to deal with natural hazards.     

Using clinical practice analysis to improve care

BACKGROUND: Improving clinical outcomes requires that physicians examine and change their clinical practice. Sustaining outcome improvements requires a dedicated and dynamic program of analyzing and improving patient care. In 1992 North Mississippi Health Services (NMHS) implemented a program to improve physicians' clinical efficiency. CLINICAL PRACTICE ANALYSIS ( CPA): CPA uses evidenced-based guidelines and examines each physician's resource utilization, processes, and outcomes for a diagnosis or procedure. Clinical practice profiles are developed, and individual performance is compared to local and national benchmarks and presented to physicians. The CPA process is used on its own or as a component of more comprehensive performance improvements projects. Physicians have been engaged in outcome improvement by more than 55 CPA projects. RESULTS: NHMS has progressively reduced its Medicare loss and its length of stay (LOS) to 4.9 days. Mortality and readmission rates have been reduced in specific diagnoses. The community-acquired pneumonia project reduced the LOS from 7.7 to 5.1 days, decreaesed the mortality rate from 8.9% to 5.0%, and decreased the cost of care from $4,269 to $3,834. The ischemic stroke project reduced the aspiration pneumonia rate from 6.4% to 0% and mortality from 11.0% to 4.6%. Patients' average LOS decreased from 10.7 days to 6.5 days, and their cost of care was reduced by $1,100 per patient. DISCUSSION: Providing individualized data has engaged physicians in improving outcomes. The program has evolved from improving efficiency to managing outcomes and from simple CPA projects to integrated performance improvement projects; however, the CPA process remains the cornerstone of the current process.     

Applied versus basic science in the literature of plant biology: A bibliometric perspective

Applied and basic approaches to scientific inquiry were compared through a bibliometric analysis of two Canadian journals in plant biology. No differences were found between the journals in the distribution of citations across different sections of research articles (that is, Introduction, Methods, Results, and Discussion). Moreover, no contrasts were found in the frequency of multiple authorships or in the age distribution of cited works. However, the journals differed significantly on three other bibliometric measures: author affiliation, number of references per article, and publication format of cited works.     

Radiation protection standards: their evolution from science to philosophy

The concept of applying constraints on individual sources to a small fraction of the public dose limit has been deemed inappropriate when shielding the medical X-ray sources. This represents a broad-based consensus of medical physics and radiological societies in the United States, and the report series on the shielding design for medical X-ray sources (including dental, X-ray imaging and therapeutic X ray) from the National Council on Radiation Protection and Measurements (NCRP) utilises 1 mSv y(-1) as a source control limit. In the present study, the rationale for such a conclusion is discussed, and a somewhat critical look at the current model of radiation protection of the public is made.     

Light-coloured grey asphalt pavements: from theory to practice

This paper presents the technological development and application of hydrated lime in treating the surface of asphalt concrete to develop light-coloured, grey asphalt pavements. When appropriately applied on the surface of fresh asphalt concrete, hydrated lime makes the surface grey, significantly increases its albedo and effectively reduces the pavement's temperature caused by hot weather. Two application case studies are presented, focusing on how to ensure hydrated lime's long-term effectiveness on the surface of asphalt pavements and take into account the effect of the subsequent reduced temperature on the resilient modulus of asphalt concrete in the design of long-life flexible pavements. The increased asphalt concrete modulus, owing to lowered temperature, can reduce the design thickness of the asphalt concrete without sacrificing pavement performance. This also has a positive influence on reduced pavement heat island effects. It is concluded that the appropriate use of hydrated lime on asphalt pavement surfaces is an effective and economical method to produce light-coloured, grey asphalt pavements.     

Artificial intelligence in science of measurements: from measurement instruments to perceptive agencies

This paper motivates, from historical, philosophical, and industrial points of view, the adoption of a novel scheme for developing complex measuring systems as perceptive agencies. The general concept of agency, a cooperative multiagent system defined within distributed artificial intelligence and robotics, is discussed together with its particular application to the field of intelligent instruments. An embryonic example of perceptive agency applied to the field of environmental monitoring is reported.     

Biocompatibility of wear-resistant coatings in orthopaedic surgery in vitro testing with human fibroblast cell cultures

The in vitro biocompatibility of six wear-resistant coatings that were devised as an alternative to polyethylene in resurfacing hip arthroplasties was assessed. The coatings were applied on glass-cover slips via the chemical vapour deposition (CVD) and physical vapour deposition (PVD) methods. Testing was performed in human fibroblast cultures and toxicity was evaluated by use of total cell surface quantitation, light and scanning electron microscopy. Multiple cracks were observed in the tungstenhydrogencarbide (WCH) and chromiumcarbide (CrC) coatings immediately after adding the growth medium. These surface alterations were not related to the presence of fibroblasts. Because of these surface changes, the general biocompatibility of WCH and CrC could not be assessed. Chromiumoxide (Cr₂O₃) caused severe alterations in cellular morphology followed by significant cytotoxicity. Alumina (Al₂O₃), titaniumnitride (TiN) and titaniumcarbide (TiC) coatings caused no adverse effects on cells in culture. The fibroblasts showed a rapid and logarithmically stable growth curve on these three materials. They merit further investigation as a wear-resistant coating for orthopaedic implants.     

Cationic liposome-DNA complexes: from liquid crystal science to gene delivery applications

At present, there is an unprecedented level of interest in the properties and structures of complexes consisting of DNA mixed with oppositely charged cationic liposomes (CLs). The interest arises because the complexes mimic natural viruses as chemical carriers of DNA into cells in worldwide human gene therapy clinical trials. However, since our understanding of the mechanisms of action of CL-DNA complexes interacting with cells remains poor, significant additional insights and discoveries will be required before the development of efficient chemical carriers suitable for long-term therapeutic applications. Recent studies describe synchrotron X-ray diffraction, which has revealed the liquid crystalline nature of CL-DNA complexes, and three-dimensional laser-scanning confocal microscopy, which reveals CL-DNA pathways and interactions with cells. The importance of the liquid crystalline structures in biological function is revealed in the application of these modern techniques in combination with functional transfection efficiency measurements, which shows that the mechanism of gene release from complexes in the cell cytoplasm is dependent on their precise liquid crystalline nature and the physical and chemical parameters (for example, the membrane charge density) of the complexes. In [section sign] 5, we describe some recent new results aimed at developing bionanotube vectors for gene delivery.     

Limits to prediction in science and design science

Design, it is argued, is inextricably bound up with the idea of science for, in carrying out design, the present as embodied in scientific knowledge forms the starting point for inventing the future. One bridge between science and design is thus contained in the notion of prediction which reveals the inevitable tensions between these activities. Prediction is concerned with the likely and possible future, design is concerned with the desirable one. Paradoxes contained therein are first explored in methodological terms and then the limits posed by scientific prediction are charted by examples using predictive computer models in urban planning.     

Discipline-based approaches to evidence-based practice: a view from nursing.

BACKGROUND: Research carried out by nurses or by others on patient problems of concern to nurses is contributing to the development of evidence-based nursing practice. In the past few decades, there has been a dramatic increase in clinical research, in health services research, and in the content and process of informatics, all focused on nursing care. The translation of findings of this research into clinical practice and the organization of nursing is less dramatic. The opportunity to implement research-based practice is great, but requires attention, methods, and resources. Also required are a database and an information system which include terms essential to nursing practice. DIMENSIONS OF NURSES' INVOLVEMENT IN EVIDENCE-BASED PRACTICE: The importance of nurses' involvement in evidence-based practice (EBP) can be viewed from three perspectives: (1) nurses' participation in medical problems and medical interventions, (2) nursing problems and nursing interventions, and (3) development and use of a standardized language that describes the problems, interventions, and outcomes important to nursing. APPLYING EBP TO COMBINED MEDICAL AND NURSING PROBLEMS: The best outcomes for a specific patient population are achieved through a combination of the medical and nursing problems and evidence-based interventions. Examples of problems of importance to nursing practice and research include pain, dehydration, incontinence, lifestyle change, confusion, immobility, knowledge deficit, noncompliance, anxiety, skin breakdown, inappropriate use of restraints, and falls. Interventions for prevention and treatment of the individual problem or combination of problems comprise the focus of nursing research and EBP.     

Workload control release mechanisms: from practice back to theory building

Much Workload Control research has focussed on the order release stage but failed to address practical considerations that impact practical application. Order release mechanisms have been developed through simulations that neglect job size variation effects while empirical evidence suggests groups of small/large jobs are often found in practice. When job sizes vary, it is difficult to release all jobs effectively—small jobs favour a short period between releases and a tight workload bounding while large jobs require a longer period between releases and a slacker workload bounding. This paper represents a return from a case study setting to theory building. Through simulation, the impact of job sizes on overall performance is explored using all three aggregate load approaches. Options tested include: using distinct load capacities for small/large jobs and prioritising based on job size or routing length. Results suggest the best solution is assigning priority based on routing length; this improved performance, especially for large jobs, and allowed a short release period to be applied, as favoured by small jobs. These ideas have also been applied to a second practical problem: how to handle rush orders. Again, prioritisation, given to rush orders, leads to the best overall shop performance.     

Estimation of radiation doses to patients and surgeons from various fluoroscopically guided orthopaedic surgeries

In this study, a mathematical method was used to estimate the entrance surface dose (ESD) to the patient and the scattered dose (Ds) to the operating surgeon during various fluoroscopically guided surgical orthopaedic procedures. For 204 patients, the procedure type, the fluoroscopy time and the highest tube potential and current values observed during fluoroscopy were recorded. For the most often performed procedures (intramedullary nailing of peritrochanteric fractures, open reduction and internal fixation of malleolar fractures and intramedullary nailing of diaphyseal fractures of the femur), the respective mean fluoroscopy times were 3.2, 1.5 and 6.3 min while the estimated mean ESDs were 183, 21 and 331 mGy, respectively. The estimated Ds rates for the hands, chest, thyroid, eyes, gonads and legs of the operating surgeon were on average to 0.103, 0.023, 0.013, 0.012, 0.066 and 0.045 mGy min(-1), respectively, and compare well with the literature. The mathematical estimation of doses cannot replace actual measurements; however, it can be used for a preliminary assessment of the radiation dose levels during various surgical procedures, so that the operator, the surgeon and the rest of the medical staff involved could be aware of the associated radiation risk and the radiation protection measures required.