bluuebunny/crossref_metadata_2025 huggingface dataset:
Ethical Issues in End‐of‐Life Geriatric Care: The Approach of Three Monotheistic Religions—Judaism, Catholicism, and Islam
Authors: Clarfield A. Mark , Gordon Michael , Markwell Hazel , Alibhai Shabbir M. H.
Published: July 2003

Ethical dilemmas pervade modern geriatric medicine. What is considered right or wrong will differ depending on, among other things, the patient's religion. The three Abrahamic monotheistic religions, Judaism, Christianity (its Catholic variant), and Islam all have carefully considered positions on medical ethics. Although much is held in common, there are significant differences. The authors present three clinical cases, each of which presents ethical dilemmas typical of geriatric care, especially at the end of life. On the basis of these scenarios, the normative ethical position of each religion is compared and contrasted. It is hoped that this approach will offer the geriatrician a useful approach to treating patients in an increasingly multicultural society.
Integrative Review of Physical Activity Intervention Research with Aging Adults
Authors: Conn Vicki S. , Minor Marian A. , Burks Kathryn J. , Rantz Marilyn J. , Pomeroy Sherry H.
Published: July 2003

This paper reviews randomized, controlled trials (RCTs) that have attempted to increase physical activity behavior by aging adults. A systematic review was necessary because numerous studies target older adults, and previous reviews have addressed a limited range of primary studies. Computerized database, ancestry, and extensive search strategies by authors of research reported in English between 1960 and 2000 located diverse intervention trials. RCTs reporting endurance physical activity or exercise behavioral outcomes for at least five subjects were included. Integrative review methods were used to summarize extant research. Forty‐two studies were retrieved. Seventeen RCTs with 6,391 subjects were reviewed. A wide variety of intervention strategies were reported. The most common interventions were self‐monitoring, general health education, goal setting, supervised center‐based exercise, problem solving, feedback, reinforcement, and relapse prevention education. Few studies individually adapted motivational interventions, used mediated intervention delivery, or integrated multiple theoretical frameworks into the intervention. Links between individual intervention components and effectiveness were not clear. Common methodological weaknesses included small samples, untested outcome measures, and time‐limited longitudinal designs. Significant numbers of aging adults increased their physical activity in response to experimental interventions. The amount of increased activity rarely equaled accepted behavior standards to achieve positive health outcomes. Further work is essential to identify successful strategies to increase activity by larger numbers of elders and to accelerate the increase in activity by those who change activity behaviors. Sex and ethnic differences need further investigation. There is a vital need for rigorously designed studies to contribute to this science.
Metastatic Prostate Cancer: Complications and Treatment
Authors: McMurtry Cynthia T. , McMurtry James M.
Published: July 2003

Despite highly successful treatments for localized prostate cancer, approximately 35% to 40% of men will eventually experience a detectable rise in serum prostate specific antigen. A portion of these men will go on to experience clinically expressed extracapsular disease, with as many as two‐thirds having evidence of bone involvement. Diagnosis of skeletal involvement involves serum markers of disease progression and radiological evaluation. Skeletal‐related events are numerous and include bone pain, spinal cord compression, vertebral collapse, and pathological fractures. Current treatments for advanced prostate cancer include individual or combined hormonal therapies, chemotherapy, radiotherapy, surgical treatments, and most recently, antiresorptive medications.
Current Status of Metals as Therapeutic Targets in Alzheimer's Disease
Authors: Finefrock Anne E. , Bush Ashley I. , Doraiswamy P. Murali
Published: July 2003

There is accumulating evidence that interactions between β‐amyloid and copper, iron, and zinc are associated with the pathophysiology of Alzheimer's disease (AD). A significant dyshomeostasis of copper, iron, and zinc has been detected, and the mismanagement of these metals induces β‐amyloid precipitation and neurotoxicity. Chelating agents offer a potential therapeutic solution to the neurotoxicity induced by copper and iron dyshomeostasis. Currently, the copper and zinc chelating agent clioquinol represents a potential therapeutic route that may not only inhibit β‐amyloid neurotoxicity, but may also reverse the accumulation of neocortical β‐amyloid. A Phase II double‐blind clinical trial of clioquinol with B12 supplementation will be published soon, and the results are promising. This article summarizes the role of transition metals in amyloidgenesis and reviews the potential promise of chelation therapy as a treatment for AD.
The Associations Between Physical Activity and Inflammatory Markers in High‐Functioning Older Persons: MacArthur Studies of Successful Aging
Authors: Reuben David B. , Judd‐Hamilton Leslie , Harris Tamara B. , Seeman Teresa E.
Published: July 2003

OBJECTIVES: To determine the relationships between recreational activity, house/yard work activity, work activity, and total physical activity and high levels of two peripheral blood markers of inflammation: interleukin‐6 (IL‐6) and C‐reactive protein (CRP).

DESIGN: Cross‐sectional study.

SETTING: Three communities (Durham, NC; New Haven, CT; and East Boston, MA).

PARTICIPANTS: Eight hundred seventy persons aged 70 to 79 who were in the top third of community‐dwelling older persons with respect to physical and cognitive functioning.

MEASUREMENTS: Blood levels of IL‐6 and CRP and self‐reported recreational activity, house/yard work activity, work activity, and total physical activity.

RESULTS: The adjusted odds ratios (AORs) for individuals with high levels of recreational activity to have values in the top tertiles of IL‐6 and CRP were 0.65 (95% confidence interval (CI) = 0.48–0.87) and 0.70 (95% CI = 0.51–0.95), respectively. The AORs for those with a high level of house/yard work activity to have values in the top tertile of IL‐6 and CRP were 0.90 (95% CI = 0.67–1.20) and 0.70 (95% CI = 0.50–0.96), respectively. High levels of house/yard work and recreational activity were independently associated with lower risk of high CRP.

CONCLUSION: The association between high levels of recreational activity and lower levels of the inflammatory markers IL‐6 and CRP suggests a mechanism for its protective effect and supports interventions that increase physical activity in older persons. Such potential benefits of increased physical activity on inflammatory markers will need to be confirmed in clinical trials.
Using the Family Covenant in Planning End‐of‐Life Care: Obligations and Promises of Patients, Families, and Physicians
Authors: Doukas David J. , Hardwig John
Published: July 2003

Physicians and families need to interact more meaningfully to clarify the values and preferences at stake in advance care planning. The current use of advance directives fails to respect patient autonomy. This paper proposes using the family covenant as a preventive ethics process designed to improve end‐of‐life planning by incorporating other family members—as agreed to by the patient and those family members—into the medical care dialogue. The family covenant formulates advance directives in conversation with family members and with the assistance of a physician, thereby making advance directives more acceptable to the family, and more intelligible to other physicians. It adds the moral force of a promise to the obligation of respecting a patient's preferences about end‐of‐life care. These negotiations between patient, family, and physician, from early planning phases through implementation, should greatly reduce the incidence of family disagreements on what the patient would have wanted. The family covenant ensures advance directive discussions within the family, promotes and respects the autonomy of other family members, and might even spur others in the family to complete advance directives through additional covenants. The family covenant holds the potential to transform moral quagmires into meaningful moral conversation.
Henry George and Classical Growth Theory: A Significant Contribution to Modeling Scale Economies
Authors: Whitaker John
Published: July 2003

It is widely recognized that the analysis of economic growth in Henry George's Progress and Poverty was considerably influenced by the British classical tradition, especially the writings of Adam Smith, David Ricardo, and John Stuart Mill. What has been less clearly perceived is that George made significant extensions to the classical theory. This paper's aim is to provide an interpretation, and to some extent a “rational reconstruction,” of George's positive analysis, largely leaving aside the striking normative lessons he drew from it. George's unsatisfactory treatment of capital is disposed of in Section I, while Section II—the core of the paper—follows George's lead in aggregating capital and labor into a single productive factor which is employed in a given natural environment. Section III adds the complication of improvement in the arts of production, and Section IV deals briefly with George's views on land speculation. Section V assesses, comparing George with his contemporary Alfred Marshall.
The Structure of Sprawl: Identifying and Characterizing Employment Centers in Polycentric Metropolitan Areas
Authors: Anderson Nathan B. , Bogart William T.
Published: July 2003

This paper applies a consistent framework to four comparably sized metropolitan areas to identify and characterize their employment centers. Employment centers are identified as places that exceed a threshold employment density and a threshold employment level. They are also characterized as specializing on the basis of location quotient analysis. We find clear evidence of specialization in every employment center in the four metropolitan areas studied. Our interpretation is that what we are observing is a systematic change in metropolitan structure rather than a random sprawling of firms. We also find some evidence that the size distribution of employment centers follows the rank‐size rule. This suggests that there is structure not only in the distribution of economic activity among the employment centers but also in their size distribution. Because less than 50 percent of metropolitan employment is within employment centers, future research should focus on understanding the more diffuse employment patterns. The rank‐size rule gives some guidance as to the expected size distribution of employment throughout the metropolitan area.
The Completely Decentralized City: The Case for Benefits Based Public Finance
Authors: Foldvary Fed E.
Published: July 2003

An alternative to centralized top‐down city governance is a multi‐level bottom‐up structure based on small neighborhood contractual communities. This paper analyzes the voting rules and public finances of decentralized, contractual urban governance and the likely outcome of such a constitutional structure, substantially reduced transfer seeking or rent seeking. Tax and service substitution, with lower‐level funding and services substituting for higher‐level public finance, is the general process by which the governance would devolve. Land rent is the most feasible source of such decentralized public finance, and local communities could also engage in local currency and credit services. Some empirical examples demonstrate the implementation of some of these governance structures.
Making the Country Work for the City: Von Thünen's Ideas in Geography, Agricultural Economics and the Sociology of Agriculture
Authors: Block Daniel , DuPuis E. Melanie
Published: July 2003

Geography, as the discipline responsible for describing the organization of space, has developed several ways of dealing with the phenomenon of the central city and its surrounding hinterlands. One of the most prominent of models used is von Thünen's Isolated State, a predictive model of how rural hinterlands organize agricultural production in relation to an urban center. Despite today's globalized food provisioning system, there are still some agricultural commodities that remain in U.S. city hinterlands. The most prominent of these is milk. The spatial organization of dairying is therefore a topic in which von Thünen's notions of centrality are still pertinent. In addition, outside of geography, his ideas had a significant effect on the agricultural economists who formulated dairy marketing policy. This paper will examine von Thünen and notions of centrality in the formulation of dairy policy in the United States. His contribution has been very important to agricultural economists and agricultural geographers but less important to sociologists of agriculture, who see the spatial organization of food production around cities due as much to contingent, local political outcomes as to law‐like notions of centrality. Comparative historical method in sociology has been particularly useful in determining the role of predictive models and contingency in determining the spatial organization of milksheds.
Development of Iterative Methods for the Exact Determination of Acid Dissociation Constants and Specific Reaction Rates in Various Ionic or Electrochemical Systems. A Review
Authors: Papanastasiou Georgios , Kokkinidis Georgios
Published: July 2003

Theory and iterative methods for analysis of potentiometric titration data are presented in this paper. The methods concern titrations of (i) weak monoprotic acids, (ii) mixtures of weak acids with their conjugate bases (buffer solutions), (iii) mixtures of two monoprotic acids, (iv) solutions of polyprotic (di- and triprotic) acids with overlapping ionisation steps, and (v) mixtures of two diprotic acids. Using equations derived without approximations and data exclusively resulting from the buffer region of a titration curve, it is possible to extract the accurate values of the concentration(s) and thermodynamic dissociation constant(s) of the titrated acid(s), even when the titration is stopped well before the end-point of the titration. The main principles of the iterative methods can also be applied to the evaluation of chronoamperometric curves for various electrochemical mechanisms (ECECE, ECE, irreversible, quasi-reversible, and CE). Thus, it is possible to extract the kinetic parameters k1 and k2 of an ECECE mechanism using exclusively chronoamperometric data. The analysis of the chronoamperometric curves for the other mechanisms (ECE, irreversible, quasi-reversible, and CE) permits the extraction of the corresponding kinetic parameters even when the values of the diffusion coefficient D and the effective area A of the electrode are not known. A review with 52 references.
Temperature Effect on the Two-Dimensional Phase Transition Kinetics of Adenine Adsorbed at the Hg Electrode/Aqueous Solution Interface
Authors: Fontanesi Claudio , Andreoli Roberto , Benedetti Luca , Giovanardi Roberto , Ferrarini Paolo
Published: July 2003

The kinetics of the liquid-like → solid-like 2D phase transition of adenine adsorbed at the Hg/aqueous solution interface is studied. Attention is focused on the effect of temperature on the rate of phase change; an increase in temperature is found to cause a decrease of transition rate.
Modulation of Internuclear Communication in Multinuclear Ruthenium(II) Polypyridyl Complexes
Authors: Browne Wesley R. , Weldon Frances , Guckian Adrian , Vos Johannes G.
Published: July 2003

The syntheses and characterisation of a series of mononuclear and dinuclear ruthenium polypyridyl complexes based on the bridging ligands 1,3-bis-[5-(2-pyridyl)-1H-1,2,4-triazol-3-yl]benzene, 1,4-bis-[5-(2-pyridyl)-1H-1,2,4-triazol-3-yl]benzene, 2,5-bis-[5-(2-pyridyl)-1H-1,2,4-triazol-3-yl]thiophene, 2,5-bis-[5-pyrazinyl-1H-1,2,4-triazol-3-yl]thiophene are reported. Electrochemical studies indicate that in these systems, the ground state interaction is critically dependent on the nature of the bridging ligand and its protonation state, with strong and weak interactions being observed for thiophene- and phenylene-bridged complexes, respectively.
Redox-Induced Ring Shuttling and Evidence for Folded Structures in Long and Flexible Two-Station Rotaxanes
Authors: Yamamoto Tohru , Tseng Hsian-Rong , Stoddart J. Fraser , Balzani Vincenzo , Credi Alberto , Marchioni Filippo , Venturi Margherita
Published: July 2003

Two dumbbell-shaped components with tetraarylmethane-type stoppers - one hydrophobic and one hydrophilic - and a rod-like section containing a tetrathiafulvalene (TTF) unit and a 1,5-dioxynaphthalene (DNP) moiety as electron-donating units, and their [2]rotaxanes, incorporating the cyclobis(paraquat-p-phenylene) (CBPQT4+) cyclophane as their electron-accepting ring component, have been synthesized, the latter using template-directed protocols. The two amphiphilic [2]rotaxanes, which differ from each other only in the lengths of the polyether chains associated with their hydrophilic stoppers, were designed in order (i) to have them exhibit enhanced amphiphilicities and, by altering the lengths of polyether chains, (ii) to improve the qualities of their Langmuir-Blodgett films, and by removing the phenolic residues, (iii) to increase the oxidative stabilities of these switchable molecules, and so extend the lifetimes of electronic devices fabricated from amphiphilic hysteretic molecular switches of this type. UV-VIS absorption and 1H NMR spectra, as well as electrochemical measurements, show that both [2]rotaxanes exist to all intents and purposes in solution as the translational isomer in which the CBPQT4+ cyclophane surrounds the TTF unit. Evidence has also been obtained for the presence in solution of folded conformations of these [2]rotaxanes. While ox/red stimulation of the TTF unit causes shuttling of the CBPQT4+ cyclophane between the TTF and DNP stations, reduction of CBPQT4+ causes unfolding of the [2]rotaxane molecules.
Electrochemical Oxidative Coupling of 4-Hydroxycinnamic Ester Derivatives: A Convenient Methodology for the Biomimetic Synthesis of Lignin Precursors
Authors: Neudorffer Anne , Deguin Brigitte , Hamel Céline , Fleury Maurice-Bernard , Largeron Martine
Published: July 2003

Based on the electrochemical oxidative coupling of 4-hydroxycinnamic ester derivatives, a straightforward biomimetic synthesis of lignin precursors is reported. This one-pot procedure leads to various naturally occurring coupling products whose distribution depends on aromatic substituents.
Rehabilitation of ligamentous ankle injuries: a review of recent studies
Authors: Zöch C , Fialka-Moser V , Quittan M
Published: July 2003

There are many treatment modalities for ankle rehabilitation. These are reviewed, and the most effective training programme for rapid restoration of ankle movement, strength, endurance, and proprioception is selected.
Effects of supramaximal exercise on the electromyographic signal
Authors: Hunter A M , St Clair Gibson A , Lambert M I , Nobbs L , Noakes T D
Published: July 2003

Aim:To determine the neuromuscular recruitment characteristics during supramaximal exercise.

Methods:Ten healthy subjects completed the Wingate anaerobic test (WAT) cycling protocol. Electromyographic (EMG) data and rate of fatigue were recorded throughout the cycling.

Results:The mean (SD) rate of fatigue (decrease in power output) was 44.5 (8.6)%. No significant change was found in EMG amplitude. A significant decrease (p<0.01) in mean power frequency spectrum was found over the 30 second period.

Conclusions:During WAT, mean power frequency spectrum was attenuated with no decline in EMG amplitude, which may be caused by an accumulation of metabolites in the periphery. However, it is also possible that the feedback loop from intramuscular metabolism to the central nervous system is unable, within the 30 second period of the WAT, to affect neural recruitment strategy.
Effects of different sodium concentrations in replacement fluids during prolonged exercise in women
Authors: Twerenbold R , Knechtle B , Kakebeeke T H , Eser P , Müller G , von Arx P , Knecht H
Published: July 2003

Objective:To investigate the effect of different sodium concentrations in replacement fluids on haematological variables and endurance performance during prolonged exercise.

Methods:Thirteen female endurance athletes completed three four hour runs on a 400 m track. Environmental conditions differed between the three trials: 5.3°C and snow (trial 1), 19.0°C and sunny weather (trial 2), 13.9°C and precipitation (trial 3). They consumed 1 litre of fluid an hour during the trials with randomised intake of fluids: one trial (H) with high sodium concentration (680 mg/l), one trial (L) with low sodium concentration (410 mg/l), and one trial with only water (W). Before and after the trials, subjects were weighed and blood samples were taken for analysis of [Na+]plasma, packed cell volume, and mean corpuscular volume.

Results:The mean (SD) decrease in [Na+]plasmaover the whole trial was significantly (p<0.001) less in trial H (2.5 (2.5) mmol/l) than in trial W (6.2 (2.1) mmol/l). Mild hyponatraemia ([Na+]plasma= 130–135 mmol/l) was observed in only six women (46%) in trial H compared with nine (69%) in trial L, and 12 (92%) in trial W. Two subjects (17%) in trial W developed severe hyponatraemia ([Na+]plasma<130 mmol/l). No significant differences were found in performance or haematological variables with the three different fluids. There was no significant correlation between[Na+]plasmaafter the run and performance. There was a significant correlation between changes in [Na+]plasmaand changes in body weight.

Conclusions:Exercise induced hyponatraemia in women is likely to develop from fluid overload during prolonged exercise. This can be minimised by the use of replacement fluids of high sodium concentration. Sodium replacement of at least 680 mg/h is recommended for women in a state of fluid overload during endurance exercise of four hours. However, higher [Na+]plasmaafter the run and smaller decreases in [Na+]plasmaduring the trials were no indication of better performance over four hours.
Football and doping: study of African amateur footballers
Authors: Ama P F M , Betnga B , Ama Moor V J , Kamga J P
Published: July 2003

Objective:To investigate use and awareness of lawful and unlawful substances by amateur footballers in Yaounde, Cameroon.

Methods:A total of 1116 amateur footballers (1037 male and 79 female) out of 1500 contacted participated in this study. They were divided into three groups: elite players (n = 314); local players (n = 723); female players (n = 79). They answered a questionnaire of 30 items grouped under six main topics: identification of players; use of lawful substances subject to certain restrictions on the International Olympic Committee (IOC) list; use of IOC banned substances; doping behaviour; awareness of doping; food supplements. The results of the questionnaire were scrutinised using Microstat software, and the level of significance was p<0.05.

Results:(a) Use by our footballers of a banned substance (cocaine) and substances subject to certain restrictions (alcoholic drinks, methylated spirits, and banga (marijuana)). (b) Doping behaviour: use by our footballers of substances with similar effects to some IOC banned substances but not listed as such: tobacco, liboga, wie-wie (narcotic), bilibili (locally made alcohol drink). (c) A large intake of vitamin C (food supplements) in all three groups. In contrast, the footballers’ knowledge of doping was vague.

Conclusion:Preventive actions and an epidemiological study of doping among footballers are urgently required.
A 16 year study of injuries to professional boxers in the state of Victoria, Australia
Authors: Zazryn T R , Finch C F , McCrory P
Published: July 2003

Objectives:Concerns about the significant injury risks in boxers have been well documented. To inform the continuing debate, updated information about the risk of injury for participants, and suitable means of modifying or preventing these risks, need to be identified.

Methods:Data describing all professional boxing fight outcomes and injuries sustained during competition, from August 1985 to August 2001, were obtained from the Victorian Professional Boxing and Combat Sports Board.

Results:A total of 107 injuries were recorded from 427 fight participations, corresponding to an injury rate of 250.6 injuries per 1000 fight participations. The most commonly injured body region was the head/neck/face (89.8%), followed by the upper extremities (7.4%). Specifically, injuries to the eye region (45.8%) and concussion (15.9%) were the most common. About three quarters of all injuries were lacerations/open wounds or superficial. No information was available on the mechanism of injury.

Conclusions:Future research should collect information on the mechanism of injury, as this is crucial for the development and implementation of effective injury prevention strategies. A suggested boxing injury report form is provided to facilitate this.
Don’t save the ball!
Authors: Macgregor D M
Published: July 2003

Objectives:To identify, over a period of 12 months, all attendances at an accident and emergency department by children over the age of 5 years with an injury to a wrist, hand, or finger, and to examine those sustained as a result of a blow from a ball.

Methods:The case notes of all children aged 6–13 years attending the Accident and Emergency Department of the Royal Aberdeen Children’s Hospital in the year 2001 as a result of a wrist, hand, or finger injury sustained from a blow by a ball were reviewed, and the cause, type, and severity of the injury noted.

Results:A total of 187 children were identified; 69% were boys and football was the main sport involved. Most (93%) were radiographed, and 40% were positive; most fractures were sustained outwith school. Hand dominance was not significant.

Conclusions:These injuries are common and may be preventable with modification of rules, equipment, and coaching. A register of youth sporting injuries may show if there are any detrimental long term effects.
Impact of school sports injury: Table 1
Authors: Abernethy L , MacAuley D
Published: July 2003

Background:Most injuries in school occur during sport. Objectives: To explore the impact of sports injury in supervised school sport.

Method:A prospective study of sports injury in children of secondary school age presenting to the accident and emergency department. Each patient was identified on registration, matched with medical records after discharge, and contacted later by telephone to complete a structured interview. Patients were only included if their injury was sustained during supervised school sport.

Results:During the study period, 194 patients aged 11–18 attended the accident and emergency department with an injury, 51% of which occurred during school sport. Injuries occurred most commonly in rugby (43%), followed by physical education and games together (17.5%). Most injuries werexrayed (72%). Just over 12% of pupils lost no time from sport, most (71%) were back to sport within three weeks, and 2.7% were injured for more than eight weeks. Almost a third of parents needed to take time off from work to deal with the injured child.

Conclusion:School sports injuries are important. They account for just over half of all injuries in secondary school children. They cause significant disruption to school and sport and have important implications for the wider family.
Insulin as a drug of abuse in body building
Authors: Evans P J , Lynch R M
Published: July 2003

A theoretical benefit of insulin abuse by body builders is that it is undetectable by currently available tests. A case is presented that highlights the dangers of such abuse.
Popliteus tendon rupture: a case report and review of the literature
Authors: Guha A R , Gorgees K A , Walker D I
Published: July 2003

Isolated rupture of the popliteus musculotendinous unit is an uncommon injury. A case is here reported of a semiprofessional athlete with a ruptured popliteus tendon without significant instability of the knee. The diagnosis was made by magnetic resonance imaging and confirmed by arthroscopy.
Avulsion fracture of the anterior superior iliac spine following apophysitis
Authors: Pointinger H , Munk P , Poeschl G P
Published: July 2003

The case of an avulsion fracture occurring in an 18 year old athlete after repeated running is presented. The fracture involved the tensor fascia lata muscle and the external oblique abdominal muscle. It was treated by open reduction and internal fixation with two screws. The patient returned to full training, including long distance running, only four weeks after the operation.
Unusual limb injury associated with sport parachuting
Authors: Ng A B Y , Alfred A , Donaldson D Q , Bale R S
Published: July 2003

The case is reported of an open injury of the right arm sustained during a parachute jump. The fracture was managed in the usual way with wound debridement, wound irrigation, skeletal stabilisation, and reconstruction of the soft tissues. Good shoulder and elbow function were achieved. The combined effort of an orthopaedic trauma surgeon and plastic surgeon is essential to improve outcomes in such cases.
Isolated dislocation of the proximal tibiofibular joint in a long jumper
Authors: Laing A J , Lenehan B , Ali A , Prasad C V R
Published: July 2003

Acute traumatic proximal tibiofibular joint dislocation is an exceedingly rare injury. This is a case report in a rare horizontal type joint variant, following a long jump injury. The diagnostic approach when this injury is suspected is described.
Localised pigmented villonodular synovitis: an uncommon cause of knee pain mimicking a meniscal tear
Authors: Roach R , dos Remedios I
Published: July 2003

A previously well 30 year old man presented with a short history of intra-articular mechanical locking, swelling, and anteromedial joint line pain. There was localised tenderness, and McMurray’s test was positive. Arthroscopy revealed a 3.6 × 2.6 × 1.5 cm firm pedicular localised pigmented villonodular synovitis originating from the insertion of the anterior horn of the medial meniscus. Owing to its size and consistency, mini-arthrotomy was required. This allowed a return to sporting activities. Localised pigmented villonodular synovitis can mimic symptoms of a meniscal tear.
Visual Basic Representations
Authors: Plotkin Eugene , Semenov Andrei , Vavilov Nikolai
Published: July 2003

We depict the weight diagrams (alias, crystal graphs) of basic and adjoint representations of complex simple Lie algebras/algebraic groups and describe some of their uses.
Monoid Presentations and Associated Groupoids
Authors: Gilbert N. D.
Published: July 2003

We consider properties of a 2-complex associated by Squier to a monoid presentation. We show that the fundamental groupoid admits a monoid structure, and we establish a relationship between its group completion and the fundamental group of the 2-complex. We also treat a modified complex, due to Pride, for monoid presentations of groups, and compute the structure of the fundamental groupoid in this setting.
Derived Varieties and Derived Equational Theories
Authors: Denecke K. , Koppitz J. , Marszałek R.
Published: July 2003

This paper describes a derivation process for varieties and equational theories using the theory of hypersubstitutions and M-hyperidentities. A hypersubstitution σ of type τ is a map which takes each n-ary operation symbol of the type to an n-ary term of this type. If [Formula: see text] is an algebra of type τ then the algebra [Formula: see text] is called a derived algebra of [Formula: see text]. If V is a class of algebras of type τ then one can consider the variety vσ(V) generated by the class of all derived algebras from V. In the first two sections the necessary definitions are given. In Sec. 3 the properties of derived varieties and derived equational theories are described. On the set of all derived varieties of a given variety, a quasiorder is developed which gives a derivation diagram. In the final section the derivation diagram for the largest solid variety of medial semigroups is worked out.
Complete Congruences on Lattices of Varieties and of Pseudovarieties
Authors: Pastijn F. , Trotter P. G.
Published: July 2003

Three methods for the construction of all complete congruences on the lattice Lv( V ) of subvarieties of a variety V are introduced. It is shown that there exists an order preserving embedding of the lattice of complete congruences on the lattice Lp( P ) of all subpseudovarieties of a given pseudovariety P into the direct product of the lattices of complete congruences on lattices of subvarieties of varieties generated by members of P; thus there are methods for constructing all complete congruences on Lp( P ). By way of application, 2ℵ0 complete congruences and complete endomorphisms are constructed on any lattice Lv( V ), where V is a certain epigroup variety which includes all bands; there is an analogous application for the lattice of all pseudovarieties of semigroups.
On Pointlike Sets and Joins of Pseudovarieties
Authors: Steinberg Benjamin
Published: July 2003

In this paper we give a criterion for a subset of a semigroup to be pointlike for the join or wreath product of two pseudovarieties. As a consequence we obtain a criterion for membership in the join of two pseudovarieties. Applications include pointlikes for J ∨ G.
The Gap Between Partial and Full
Authors: Almeida J. , Volkov M. V.
Published: July 2003

We show that the interval of the lattice of semigroup pseudovarieties between the pseudovarieties generated by all semigroups of full and respectively, partial, order-preserving transformations of a finite chain, contains a chain isomorphic to the chain of real numbers (with the usual order). Similar results are proved for several related intervals.
On The Schützenberger Product of Three Copies of a Free Group
Authors: Neto O. , Sezinando H.
Published: July 2003

We show that the Schützenberger product "cut down to generators" of three copies of a free group is a relatively free monoid with involution. We show that its set of idempotents has a natural structure of a semilattice. This semilattice is naturally isomorphic to the semilattice of idempotents of a free inverse monoid.
A Variety with Undecidable Equational Theory and Solvable Word Problem
Authors: Crvenković Siniša , Dolinka Igor
Published: July 2003

In this paper, we exhibit an example of a variety with only one binary operation having recursive base, undecidable equational theory and solvable word problem.
A Variety Where the Set of Subalgebras of Finite Simple Algebras is Not Recursive
Authors: Kublanovsky Stanislav , Sapir Mark
Published: July 2003

We construct a finitely based variety of algebras with two binary operations where the set of subalgebras of finite simple algebras is not recursive.
A Stochastic Model for Service Contract
Authors: Murthy D. N. P. , Asgharizadeh E.
Published: July 2003

When it is not economical to carry out maintenance in-house, out-sourcing to an external agent is an alternate viable option. In this paper, we study a simple maintenance service contract involving a single agent (providing the maintenance service) and a single customer (owner of the equipment and recipient of the maintenance service). We develop a simple model to obtain the optimal strategies for both the customer and the agent. We give a complete characterization of the strategies along with some sensitivity analysis and discuss some extensions.
An Integrated Customer-Focused Approach for Quality and Reliability
Authors: Kapur Kailash C.
Published: July 2003

Quality and reliability for a product or process is defined and evaluated by the customer. Reliability is a time oriented quality characteristic. Time is a compound noise factor, and a reliable product/process must be robust against time. Similarly, a system has several quality characteristics which create impacts on customer satisfaction. This paper develops an integration of several quality and reliability methodologies such as robust design, quality engineering, quality function deployment (QFD), reliability engineering, and strategies for system integration. The objective is to develop a customer-focused approach for quality and reliability.
Computer Aided Reliability and Robustness Assessment
Authors: Sudjianto Agus , Juneja Lokesh , Agrawal Hari , Vora Mahesh
Published: July 2003

The competitive pressure to shorten product development time has necessitated the automotive industry to rely more on Computer Aided Engineering (CAE) for analyzing and proving product reliability and robustness. The challenge of this approach is the incorporation of product variability, due to manufacturing and customer usage variations in the analysis, requires a massive computation process which may be prohibitive even with today's advanced computers. In this paper, we demonstrate the use of an efficient computational procedure based on optimal Latin Hypercube Sampling (LHS) and a "cheap-to-compute" nonlinear surrogate model using Multivariate Adaptive Regression Splines (MARS) to emulate a computationally intensive complex CAE model. The result of the analysis is the identification of sensitivity of design parameters, in addition to a computationally affordable reliability assessment. Fatigue life durability of automotive shock tower is presented as an example to demonstrate the methodology.
A Bayesian Approach for Assessing Software Quality and Productivity
Authors: Humphrey Watts S. , Singpurwalla Nozer D.
Published: July 2003

This paper introduces a statistical model for analyzing and assessing human-performance parameters such as software quality and productivity. We may refer to this model as a growth curve model because, for suitably chosen values of its constants, we can fit a learning curve to data with trend characteristics. Using data from a programming professional's experience with a range of exercises, we demonstrate the use of this model for assessing software quality and productivity. The model uses a nonhomogeneous autoregressive process, in which Bayesian statistical procedures have been developed. To obtain the desired capability, the model uses more complex statistical methods and requires more extensive initial condition estimates than methods based on exponential smoothing. As a consequence, this model should generally provide superior facilities for tracking and measuring overall trends. Since this is a trend-following model, its projections will tend to excel for highly trended data. On the other hand, since each new value is projected by applying the current trend information to the most recent data, its projections will not be very accurate in highly variable situations. The methodology of this paper is general and can be applied to situations other than those of software quality and productivity.
An Information Theoretic Approach to Predicting Software Faults
Authors: Khoshgoftaar Taghi M. , Allen Edward B.
Published: July 2003

Software measurement and modeling is intended to improve quality by predicting quality factors, such as reliability, early in the life cycle. The field of software measurement generally assumes that attributes of software products early in the life cycle are somehow related to the amount of information in those products, and thus, are related to the quality that eventually results from the development process.

Kolmogorov complexity and information theory offer a way to quantify the amount of information in a finite object, such as a program, in a unifying framework. Based on these principles, we propose a new synthetic measure of information composed from a set of conventional primitive metrics in a module. Since not all information is equally relevant to fault-insertion, we also consider components of the overall information content. We present a model for fault-insertion based on a nonhomogeneous Poisson process and Poisson regression. This approach is attractive, because the underlying assumptions are appropriate for software quality data. This approach also gives insight into design attributes that affect fault insertion.

A validation case study of a large sample of modules from a very large telecommunications system provides empirical evidence that the components of synthetic module complexity can be useful in software quality modeling. A large telecommunications system is an example of a computer system with rigorous software quality requirements.
New Results on Goodness-of-Fit Tests for the Power-Law Process and Application to Software Reliability
Authors: Crétois Emmanuelle , Gaudoin Olivier
Published: July 2003

The Power-Law process, also known as the Duane model, is a nonhomogeneous Poisson process which is widely used in reliability growth modeling. Goodness-of-fit tests for this process have been proposed by Crow, Rigdon, Klefsjö–Kumar and Park–Kim. In this paper, we propose several new tests based on chi-square, Laplace and conditional probability integral transform (CPIT) methodologies. We show that the TTT-plot test reduces to the Laplace test with Durbin's modification. We compare the power of 15 goodness-of-fit tests for the Power-Law process, and apply them to real software reliability data.
Optimal Designs of Simple Step-Stress Accelerated Life Tests for Lognormal Lifetime Distributions
Authors: Chung Sang Wook , Bai Do Sun
Published: July 2003

This paper considers optimal designs of step-stress accelerated life tests in which each lognormally-distributed test item is first run at low stress, and if it does not fail for a specified time, then it is run at high stress until a predetermined censoring time. It is assumed that a log-linear relation exists between the lognormal location parameter and stress, and that a cumulative exposure model for the effect of changing stress holds. The optimum stress change point minimizes the asymptotic variance of maximum likelihood estimator of a specified percentile at design stress. For selected values of the design parameters, the optimum plans are tabulated. Designs of high-to-low step-stress accelerated life tests (ALTs) in which each item is first run at high stress and then at low stress, and the optimality criterion of minimizing the generalized asymptotic variance of maximum likelihood estimators of model parameters, are also considered. The effects of the incorrect pre-estimates of the design parameters are investigated.
Impact of Unspecified Interactions on the Effectiveness of Taguchi's Parameter Design
Authors: Dong Fang , Goh T. N.
Published: July 2003

The common version of Genichi Taguchi's parameter design entails a marginal analysis procedure for determining parameter settings that will maximize or minimize a response. Unless all significant parameter interactions are known a priori and provided for in the orthogonal array of the parameter design experiment, conclusions drawn from marginal analysis will not necessarily be correct. In this paper, the probability that the routine parameter design procedure will actually succeed in realizing the optimization objective is discussed, followed by illustrations based on data from the commonly cited literature.
Identify Generators for 2k - p Experiments Using Taguchi Orthogonal Arrays
Authors: Chen Chuen-Lung , Khan Muhammad Arshad , Wu Chyng-Min
Published: July 2003

Two-level fractional factorial design is an efficient technique for experiments considering a large number of factors. To evaluate the efficiency and analyze the data for such a design, we need to know the generators for the design, so that, using the generators, we can generate its defining relation and alias structure. Although knowing the generators is important for a two-level fractional factorial design, it is not unusual in actual industrial situations for the generators used in the design to be lost or overlooked while the design is performed. Since Taguchi methods has been widely applied in industry, in this research, an efficient algorithm based on Taguchi orthogonal arrays (OA's) and interaction tables is developed to identify the generators for given designs. Furthermore, with the investigation of the insights of Taguchi OA's and interaction tables, this research may provide ideas for making Taguchi methods a simple tool for developing optimal designs for 2k - p experiments.
Statistical Model Explaining the Fine Structure and Interface Reference of Localized Excitons in Type-II GaAs/AlAs Superlattices
Authors: Belousov M. V. , Chernyshov A. Yu. , Ignatev I. V. , Kozin I. E. , Kavokin A. V. , Gibbs H. M. , Khitrova G.
Published: July 2003

Raman scattering experiments have allowed the determination of the spatial distribution of the thicknesses of GaAs and AlAs layers in a gradient GaAs/AlAs superlattice. A statistical model is developed which is consistent with all the data and ways to improve interface quality are suggested. The fine structures of XΓ and ΓΓ excitons observed in photoluminescence and differential reflection are found to be governed by the fractional parts of the average thickness of the layer (in monolayers). We conclude that each structure has two scales of fluctuations which form the relief of the AlAs surface. The largest fluctuations repeat the relief of the GaAs surface. The second scale has the size of a typical XΓ exciton Bohr radius. The smaller fluctuations disappear when the thickness of the AlAs layer is equal to an integer number of monolayers, which provide interfaces of the quality. The correlation of macro-rough fluctuations on the surface of AlAs and GaAs causes an asymmetry in the densities of states of type II excitons located at either AlAs-on-GaAs or GaAs-on-AlAs interfaces. Hence the lowest PL line is formed by excitons localized across the AlAs-on-GaAs interface. On the other hand, in structures with micro-rough but uncorrelated AlAs surfaces, the lowest energy state is expected to be occupied by excitons localized across the GaAs-on-AlAs interface.
Multiple Quantum Well Heterostructures Showing Optical Nonlinearities at Low Intensity and Fast Recovery
Authors: Gastaldi L. , Rigo C. , Campi D. , Faustini L. , Coriasso C. , Cacciatore C. , Soldani D. , Bossi M. C.
Published: July 2003

This paper focuses on photogenerated carrier nonlinearities in InGaAs/InAlAs quantum wells (QWs) that use low optical power, display a relatively fast recovery time (280 ps down to 35 ps), and excellent optical properties in terms of the sharpness of the absorption edge. A guided-wave, all-optical switching device is demonstrated as an application, at a wavelength which is of interest to telecommunication systems (1.55 μm) and requires low control energy (<0.3 pJ/pulse). A key issue here is that the controlled introduction of defects in the QW heterostructures allows the time response to be fastened significantly without being detrimental to the performance of the device in terms of on-off contrast and switching energy. The preparation procedure is compatible with metalorganic-based growth techniques widespread in optoelectronics at 1.55 μm.