bluuebunny/crossref_metadata_2025 huggingface dataset:
The Effectiveness of Riparian ‘Restoration’ on Water Quality—A Case Study of Lowland Streams in Canterbury, New Zealand
Authors: Collins Kathryn E. , Doscher Crile , Rennie Hamish G. , Ross James G.
Published: May 2012

In New Zealand, around half of the lowland water bodies do not meet water quality standards, primarily due to widespread changes in land use. Riparian restoration has been occurring in New Zealand for over 30 years in an effort to minimize this impact, however, little monitoring of restoration effectiveness has been undertaken. This study evaluated the impact of riparian plantings on water quality of lowland streams in the Lake Ellesmere catchment. A paired‐catchment design on four river reaches was used to compare restored riparian buffers with control sites upstream. Chemical water quality sampling was used in conjunction with a macroinvertebrate community assessment. Equivocal benefits of riparian restoration were observed, with improvements in some variables but not in others. Riparian restoration had a positive effect on water quality in terms of increasing dissolved oxygen and decreasing turbidity. However, conductivity increased at planted sites and no changes were observed in other variables. These findings may be affected by the insufficient width of all four buffers, and gaps in the buffer system contributing to poor water quality. Although variable responses were seen in invertebrate community composition, this research suggests that even narrow planted buffer strips may be effective in improving some water quality parameters. The overall mixed results present a fair assessment of the benefits of riparian restoration that may be expected within a relatively short time following vegetation establishment. Even when no baseline data have been established prior to restoration, this research showed monitoring can demonstrate the effectiveness of riparian restoration.
Genetic Delineation of Local Provenance in Persoonia longifolia: Implications for Seed Sourcing for Ecological Restoration
Authors: Stingemore Jessica A. , Krauss Siegfried L.
Published: May 2012

Restoration of diverse native plant communities typically requires the collection of large amounts of seed. Thus, practitioners often struggle to find adequate supplies near project sites and need to know from how far they can collect without compromising restoration success—how far does local provenance extend? We addressed this issue by assessing genetic variation within, and differentiation among, 12 potential seed source populations of Persoonia longifolia, a key component of the jarrah forest of Western Australia. An analysis of molecular variance of 66 polymorphic amplified fragment length polymorphism markers partitioned 92% of the total genetic variation within populations and 8% among populations, indicating relatively weak but statistically significant population genetic differentiation. Ordination of these genetic data showed marked west/east and north/south gradients. Pairwise population genetic dissimilarity was correlated with both geographic distance and environmental distance derived from five climate variables. However, partial Mantel tests showed that the relationship between genetic and geographic distance was not independent of environmental distance, suggesting a non‐neutral signature in these markers. Bayesian outlier analysis identified two markers, and spatial analysis method tests identified highly significant associations between these two markers and three environmental variables. Frequency differences at these markers across populations suggested the possibility of climatically adapted provenances. The global significance value from analyses of similarities for these two markers correlated to a general provenance distance of 47 km, in contrast to a threshold of 60 km for the complete dataset. Guidelines for seed sourcing that consider these population genetic data should lead to more effective ecological restoration with this species.
Is the wait‐for‐patient‐to‐come approach suitable for African newcomers to Alberta, Canada?
Authors: Amin Maryam , Perez Arnaldo
Published: May 2012

Objectives

A qualitative study was conducted to identify psychosocial barriers to providing and obtaining preventive dental care for preschool children among African recent immigrants.

Methods

Seven focus groups were conducted with 48 mothers of 3‐ to 5‐year‐old children from Ethiopian, Eritrean, and Somali communities in Edmonton. Participants had lived in Canada for 5 years or less. Three debriefing interviews were conducted with the community health workers who facilitated the focus groups in participants' first languages. Data analysis consisted of assigning codes, grouping codes into existing or new categories of barriers, grouping identified categories into domains, and organizing categories and domains around a general perspective of psychosocial barriers to prevention of caries.

Results

Barriers to prevention of early childhood caries (ECC) were associated with home‐based prevention, early detection, and access to professional care. Barriers to parental prevention were related to health beliefs, knowledge, oral health approach, and skills. Barriers to early detection included perceived role of caregivers and dentists, perceived identity of ECC, ways of detecting cavities, and parental self‐efficacy. Access barriers were related to parental knowledge of preventive services, attitudes toward dentists and dental services, English skills, and external constraints concerned dental insurance, social support, time, and transportation.

Conclusions

Preventive interventions should be aimed at assisting primary caregivers with providing and obtaining adequate dental care for their children through enhancing oral health literacy, developing new set of oral health–related skills, reducing environmental constraints, and strengthening their intention of obtaining professional preventive dental services.
Association of BDNF Gene Polymorphism with Bipolar Disorders in Han Chinese Population
Authors: Wang Z. , Li Z. , Chen J. , Huang J. , Yuan C. , Hong W. , Yu S. , Fang Y.
Published: May 2012

Recent data suggest that brain‐derived neurotrophic factor (BDNF) plays an essential role in neuronal plasticity and etiology of bipolar disorders (BPD). However, results from different studies have been inconsistent. In present study, 342 patients who met DSM‐IV (Diagnostic and Statistical Manual of Mental Disorders, 4th Edition) criteria for bipolar disorders type I (BPD‐I) or type II (BPD‐II) and 386 matched health controls were enrolled, and TaqMan® SNP Genotyping Assays (Applied Biosystems, Foster City, CA, USA) were applied to detect the functional polymorphism rs6265 (Val66Met) of BDNF gene. Treatment response to lithium and valproate was retrospectively determined. The association between Val66Met polymorphism and BPD, treatment response to mood stabilizers, was estimated. The genotype and allele distribution of Val66Met polymorphism between BPD patients and control subjects showed significant difference (genotype: χ2 = 6.18, df = 2, P = 0.046; allele: χ2 = 5.01, df = 1, P = 0.025) with Met allele as risk factor for disease susceptibility (OR = 0.79, 95%CI as 0.64–0.97). The post hoc analysis interestingly showed that Met allele had opposite effect on the treatment response for BPD‐I and BPD‐II separately. For BPD‐I patients, the response score in Val/Val group was significantly lower than that in Met allele carriers (t = −2.27, df = 144, P = 0.025); for BPD‐II patients, the response score in Val/Val group was significantly higher than that in Met allele carriers (t = 2.33, df = 26, P = 0.028). Although these results should be interpreted with caution because of the limited sample for Val/Val genotype in BPD‐II patients (N = 5), these findings strengthen the hypothesis that BDNF pathway gets involved in the etiology and pharmacology of BPD and suggest the differences between BPD‐I and BPD‐II.
Characteristics of older and younger patients with suspected paracetamol toxicity
Authors: Kane Alice , Mitchell Sarah J , Carroll Peter R , Matthews Slade , Hilmer Sarah N
Published: May 2012

Aim:  The aim of this study was to compare the characteristics of older and younger patients with suspected paracetamol toxicity.

Methods:  A retrospective audit of the medical records of older (≥65 years, n= 25) and younger (20–30 years, n= 50) patients with a detectable paracetamol level at a Sydney hospital.

Results:  Older patients showed a different clinical pattern of suspected paracetamol toxicity and were more likely than younger patients to have multifactorial elevation of liver function tests. Additionally, older age was more likely to be associated with chronic therapeutic paracetamol dosing (71% older, 6% younger, P < 0.001), or with accidental toxic exposure (90% older, 29% younger, P < 0.001), while younger patients were more likely to have a deliberate high‐dose exposure (10% older, 71% younger, P < 0.001).

Conclusions:  The age‐related differences in paracetamol exposure, paracetamol levels and liver function tests described in this population should be considered when ordering and interpreting paracetamol levels.
What’s the Harm in Asking About Suicidal Ideation?
Authors: Mathias Charles W. , Michael Furr R. , Sheftall Arielle H. , Hill‐Kapturczak Nathalie , Crum Paige , Dougherty Donald M.
Published: May 2012

Both researchers and oversight committees share concerns about patient safety in the study‐related assessment of suicidality. However, concern about assessing suicidal thoughts can be a barrier to the development of empirical evidence that informs research on how to safely conduct these assessments. A question has been raised if asking about suicidal thoughts can result in iatrogenic increases of such thoughts, especially among at‐risk samples. The current study repeatedly tested suicidal ideation at 6‐month intervals for up to 2‐years. Suicidal ideation was measured with the Suicidal Ideation Questionnaire Junior, and administered to adolescents who had previously received inpatient psychiatric care. Change in suicidal ideation was tested using several analytic techniques, each of which pointed to a significant decline in suicidal ideation in the context of repeated assessment. This and previous study outcomes suggest that asking an at‐risk population about suicidal ideation is not associated with subsequent increases in suicidal ideation.
Accident Occurrence and Functional Health Patterns: A Pilot Study of Relationships in a Graduate Population
Authors: Sheerin Fintan K. , Curtis Elizabeth , de Vries Jan
Published: May 2012

PURPOSE:  This pilot study sought to examine the relationship between functional health patterns and accident proneness.

METHODS:  A quantitative‐descriptive design was employed assessing accident proneness by collecting data on the occurrence of accidents among a sample of university graduates, and examining this in relation to biographical data and information collated using the Functional Health Pattern Assessment Screening Tool (FHPAST). Data were analyzed using descriptive and inferential statistics.

FINDINGS:  One FHPAST factor predicted more frequent sports accidents. Age was also shown to be a significant predictor but in a counterintuitive way, with greater age predicting less accident proneness.

CONCLUSION:  The FHPAST may have a role to play in accident prediction.

IMPLICATIONS FOR NURSING PRACTICE:  Functional health pattern assessment may be useful for predicting accidents.
SECTION OF MATHEMATICS AND ENGINEERING: THE CORRELATION OF FOUR‐BAR STRAIGHT‐LINE MOTION DEVICES BY MEANS OF THE ROBERTS THEOREM AND A DIRECT PROOF OF THE LATTER*
Authors: de Jonge A. E. Richard
Published: May 2012

This paper deals with all the known straight‐line mechanisms of four bars showing their variants in numerous figures. Next it considers a new and simple direct proof of the Roberts Theorem and shows that the general assumption of two mechanisms existing which describe the same coupler curve when one hinge is replaced by a sliding pair holds true only for the “outer” or fixed hinges, but not for the inner or moving hinges, in which case there exists only one mechanism. This was not known previously.

Finally, this paper demonstrates the application of the Roberts Theorem to the correlation of the four‐bar straight‐line mechanisms described and depicted in the first part. It also shows that the real reason for the results of the correlation lies in the position of the various mechanisms in the curvature system.
SECTION OF GEOLOGICAL SCIENCES: THE NATURE OF GEOLOGY AND ITS PLACE AMONG THE NATURAL SCIENCES*
Authors: Spieker Edmund M.
Published: May 2012

To learn without thinking is useless;

to think without learning is dangerous

Confucius
SUBCULTURAL STUDIES OF HOMELESS MEN*
Authors: Levinson Boris M.
Published: May 2012

This stupid world where

Gadgets are gods and we go on talking

Many about much, but remain alone

Alive but alone, belonging‐where?

Unattached as tumbleweed. (Auden, 1946. p.44.)
SECTION OF CHEMICAL SCIENCES: APPROACHES TO CYCLOBUTADIENE*
Authors: MÜLLER Eugen , Sauerbier Michael , Heiss Jürgen
Published: May 2012

We tried to prepare a cyclobutadiene system by irradiating compounds containing triple bonds in an appropriate geometry, e.g. o‐bis(phenylethinyl)‐benzene and 1, 2‐diethinyl‐4, 5‐dimethyl‐benzene. Instead of cyclobutadiene derivatives still unknown dimeric systems are formed in an escape reaction. These new systems are bis‐azulenes that formally contain a s‐indacene but preferentially have a quasi‐aromatic character. There are strong indications that cyclobutadiene is an unstable intermediate of the photoreaction.
VIOLATION OF THE NONCROSSING RULE: THE HUBBARD HAMILTONIAN FOR BENZENE*
Authors: Heilmann Ole J. , Lieb Elliott H.
Published: May 2012

Abstract

The Hubbard Hamiltonian, while not one of the most successful models for φ electrons in benzene, has been extensively investigated in the literature. As part of our general study of that model, we have computed all the energy levels for all values of the repulsion parameter—a task that has not been undertaken before. After extracting all the symmetry of the model we found, to our great surprise, many instances of permanent degeneracy of levels with different symmetry and also crossing of levels of the same symmetry. We can also demonstrate that there is no hidden symmetry to account for these effects. Since these results run counter to one of the oldest folk theorems in quantum chemistry, our otherwise uninspiring graphs may be of general interest.
PLEISTOCENE GEOLOGY OF CROTON POINT, N.Y.*
Authors: Markl Rudi G.
Published: May 2012

Abstract

Croton Point, a peninsula projecting westward into the Hudson River, is inferred to have originated by deltaic deposition of glacial outwash in a postglacial lake that formerly existed in the Hudson valley.
HEAT TRANSFER THROUGH FABRICS AS RELATED TO THERMAL INJURY*†
Authors: Stoll Alice M. , Chianta Maria A.
Published: May 2012

Abstract

Heat is transferred through fabrics by convection, conduction, and radiation and, under certain circumstances, by vaporization. Each mode is subject to different physical principles, but the effect of the total heat absorbed by underlying skin is the same: If the resultant skin temperature rise is sufficiently high and maintained sufficiently long, injury results. The extent of injury is predicted under certain controlled conditions, and these conditions may be used to disclose protection principles appropriate to each mode of transfer.
FROM MENDELÉEV'S ATOM TO THE COLLAPSING STAR*†
Authors: Wheeler John Archibald
Published: May 2012

Abstract

A decade before Planck's 1900 formulation of the quantum principle, Mendeléev, out of his researches on chemistry and the periodic system of the elements, recognized the general character that the new principle must have, dealing with no “deathlike inactivity,” establishing “individuality amid continuity,” and destined to “hasten the advent of true chemical mechanics.” Implicit in the Bohr‐Rutherford 1911 model of the atom was the paradox of atomic collapse. No cheap way out offered itself. Only application of the quantum principle resolved the paradox. This development led (1917) to the “chemical mechanics” envisaged in outline by Mendeléev. It may be symbolized today by an electron orbit with the shape of a double necklace, the “chemical orbit” (Robert Powers). A new crisis confronts physics today in the predicted phenomenon of gravitational collapse, both at the level of a star (“black hole physics”) and at the level of the universe itself. Again, no way out is evident except to call on the quantum principle. It leads to the conclusion that the dynamics of the universe goes on in superspace. In superspace, alternative dynamical histories of the universe (cycles of expansion and recontraction) not only dynamically couple to each other in the era of collapse, as well as one can judge, but also “coexist.” If the vision of Clifford and Einstein in updated form is taken as guide and particles are regarded as quantum states of excitation of a dynamic geometry, then it is natural to believe that each period of collapse sees the universe “reprocessed,” with the previous spectrum of particle masses extinguished and a new pattern of masses established. On this view, particle masses are as far removed from any possibility of being calculated from first principles as the “initial conditions of dynamics” themselves. For an early test of this framework of ideas nothing looks so promising as the prediction that a black hole, formed by whatever combination of baryons, photons, leptons, and other entities, is characterized by nothing but mass, charge, and angular momentum (“transcendence of the law of conservation of baryons and leptons”).
CARDIAC PERFORMANCE AND METABOLISM IN SHOCK DUE TO ACUTE MYOCARDIAL INFARCTION IN MAN: RESPONSE TO CATECHOLOMINES AND MECHANICAL CARDIAC ASSIST*†
Authors: Mueller Hiltrud , Ayres Stephen M. , Giannelli Stanley , Conklin E. Foster , Mazzara James T. , Grace William J.
Published: May 2012

Summary

Systemic hemodynamics and myocardial metabolism were studied in 21 patients in shock due to acute myocardial infarction. The response to isoproterenol was determined in six, to l‐norepinephrine in eight, and to intra‐aortic counterpulsation in 10 patients. Before treatment, cardiac index was markedly reduced, averaging 1.35 L/min/m2. Mean aortic pressures ranged between 40 and 65 mm Hg, while systemic vascular resistance varied widely, averaging 1,575 dynes‐sec‐cm−5. Decreases in coronary blood flow (mean 68 ml/100 g/min) and in myocardial oxygen consumption (mean 8.11 ml/100 g/min) were associated with abnormally high myocardial oxygen extraction (mean 78%) and with lactate production (mean 9%). Isoproterenol increased cardiac index and heart rate an average of 0.85 L/min/m2 and 25 beats/min. Coronary blood flow rose an average of 12 ml/100 g/min in face of unchanged mean aortic pressure, while diastolic aortic pressure fell uniformly. Myocardial lactate metabolism deteriorated. L‐norepinephrine increased mean aortic pressure and coronary blood flow an average of 21 mm Hg and 27 ml/100 g/min. Mean myocardial oxygen consumption rose 2.24 ml/100 g/min. While myocardial lactate production shifted to extraction (mean 12%), myocardial oxygen extraction remained abnormally high (mean 73%). Cardiac index did not improve. Intra‐aortic counterpulsation increased mean aortic pressure and coronary blood flow an average of 15 mm Hg and 23 ml/100 g/min. Myocardial oxygen consumption remained essentially unchanged. Both myocardial lactate and oxygen extraction improved towards normal values (mean 15% and 61%). Cardiac index increased an average of 0.45 L/min/m2. Conclusion: Hemodynamics and myocardial metabolism were markedly abnormal in shock due to acute myocardial infarction. Isoproterenol improved cardiac performance, but myocardial oxygenation deteriorated. Therefore, isoproterenol does not seem to be helpful in coronary shock. L‐norepinephrine improved myocardial perfusion and oxygenation, while cardiac output remained unchanged. Nevertheless, l‐norepinephrine appears to be the vasoactive agent of choice in the initial treatment of coronary shock. Intra‐aortic counterpulsation changed myocardial metabolism towards normal and improved systemic perfusion. Mortality remained unchanged, however, during the three different therapeutic interventions, emphasizing the importance of early recognition of the shock state and of further aggressive diagnostic and therapeutic management.
ATHEROSCLEROTIC HEART DISEASE AND THE ENVIRONMENT*
Authors: Peacock Peter B.
Published: May 2012

Abstract

Environmental factors associated with an increase in manifest coronary artery disease are temperature extremes, noise, soft water, exposure to sulfur dioxide and carbon monoxide, and constraints imposed by the living habits of the community concerned. The important constraints are the relative nonavailability of high‐protein foods that are low in saturated fat and cholesterol, the general acceptance of cigarette smoking as permissable behavior, the lack of emphasis on preventive medicine and limitations on physical exercise.
ENTROPY PRODUCTION IN AN EXPANDING GAS‐FILLED UNIVERSE*
Authors: Anderson J. L. , Witting H. R.
Published: May 2012

Abstract

The entropy generated in an expanding gas‐filled universe is calculated for an expansion that takes place in a series of steps during which the gas is collisionless. At the end of each step the gas is allowed to thermalize before undergoing its next expansion step. The results of the calculation show that entropy is generated only during a brief period in the evolution of the gas and that the total dimensionless entropy per baryon generated (∼10) is insufficient to explain the existence of the 108 per baryon of dimensionless entropy that appears to exist in the universe.
SOME DETERMINANTS OF EXPECTANCY OF SUCCESS*
Authors: McMahan Ian D.
Published: May 2012

Abstract

Male and female subjects in sixth‐grade, tenth‐grade, and college classes attempted to solve five anagrams, stating their expectancy of success prior to each anagram and their causal attributions for success and failure following each anagram; at the conclusion of the task they assessed the factors responsible for their performance. They then stated the number of simple addition problems they expected to solve in a limited time, attempted the problems, and assessed the factors responsible for their performance. The results support a model of achievement behavior derived from attribution theory and suggest that among the determinants of expectancy of success are the person's perceptions of his ability for the task and of the outcomes of previous encounters with it, as well as achievement‐related social stereotypes such as sex‐role stereotypes. Some possible implications of the results for remedial education are suggested.
FRENCH COLONIALISM AS REFLECTED IN THE MALE‐FEMALE INTERACTION IN MOROCCO*
Authors: Vinogradov Amal
Published: May 2012

Abstract

This paper examines some of the disruptive effects of French colonialism on the traditional Moroccan society, specifically in terms of the male‐female relationship. By challenging the accepted cultural image of the male and undermining his protective functions towards the female, the French contributed to the normative dissonance of the society and exacerbated the existing sexual tensions. Moroccans complain about the inflated bride prices, marital instability, and prostitution, all of which are seen as indeces of the prevalent sexual role ambivalences and contradictions.
THE IDENTIFICATION OF RISK FACTORS IN EMPLOYED POPULATIONS*
Authors: Pell Sidney
Published: May 2012

Abstract

Industrial populations provide unique opportunities for epidemiologic research to study risk factors in chronic disease and identify health hazards in the work environment. In such populations, demographic, morbidity, and mortality data are readily accessible and generally reliable. Moreover, industrial populations are usually stable enough to permit long‐term follow‐up for prospective studies. In this paper, the major findings of several epidemiological studies done in a large corporation are reviewed.
NEW DELIGHTS FROM AN OLD POLYOLEFIN: A RETURN TO THE CHEMISTRY OF CYCLOOCTATETRAENE*
Authors: Paquette Leo A.
Published: May 2012

Abstract

The nonthermal structural rearrangements of cyclooctatetraene to semibullvalene and 2,3‐dihydrotriquinacen‐2‐one are described. The first pathway, which is entirely general in its scope, entails as its key step the Ag(I)‐catalyzed 1,8‐bishomocubane → snoutane isomerization reaction. Subsequent hydrolysis‐oxidation provides 9,10‐diazasnoutenes, which cannot be isolated but lose nitrogen rapidly with generation of the semibullvalenes. The equilibrium imbalances that arise upon monosubstitution and 2,8‐annulation of this divinylcyclopropane system are also outlined. Cycloaddition of TCNE to cyclooctatetraeneiron tricarbonyl affords an unusual α,π‐Fe(CO)3 complex, oxidative decomposition of which gives 2,2,3,3‐tetracyanodihydrotriquinacene. A four‐step conversion of the latter to triquinacene‐2‐carboxylic acid is outlined. Resolution of the acid and conversion of the chiral material to (+)‐2,3‐dihydrotriquinacen‐2‐one serves as a prelude to dimerization of these “halves” to potential dodecahedrane precursors. The thermally promoted degenerate isomerization and rearrangement reactions of a variety of cyclooctatetraenes are next presented. Lastly, the latent potential of the [8]annulene ring system to function as a neighboring group in carbonium ion processes is discussed.
A DISCONTINUOUS SURFACE ON THE CENTRAL NEW YORK DRUMLIN PLAIN
Authors: Miller Jesse W.
Published: May 2012

Abstract

A remarkably flat, discontinuous surface is associated with the northern portion of the Ontario Lake Plain drumlin field in central New York. Possible explanations include a preglacial or interglacial erosion surface, a glacial lake bottom, a wave‐eroded surface, and outwash surface, or a surface of glacial erosion. The most plausible hypothesis entails a glacial readvance over a wave cut and subaerially eroded plain.
A NOVEL TYPE OF RESISTANT BACTERIA INDUCED BY GENTAMICIN*
Authors: Li Koibong , Farmer J. J. , Coppola Antonio
Published: May 2012

Abstract

Following growth of Serratia marcescens in the presence of gentamicin, both a normal resistant mutant and a pleiotropic resistant variant, Serratia marcescens, were isolated. The pleiotropic variant strain differed from the parent strain in antibiotic susceptibility profile, colonial morphology, biochemical properties, and susceptibility to Serratia bacteriophages and bacteriocins but was identical in bacteriocin production. While the pleiotropic variant was stable in the absence of gentamicin, reversion to the parent was found in cultures grown aerobically, but not anaerobically. The normal resistant mutants, of apparent spontaneous origin, did not exhibit pleiotropic effects. The pleiotropic variant grew better under anaerobic conditions than it did under aerobic conditions, while the parent strain grew better aerobically. Both the parent strain and the variant were capable of adapting to either environment. The difficulty of identifying this variant in a clinical microbiology laboratory is discussed.
A STUDY OF THE SHOCK LOADING OF MATERIALS
Authors: Rolsten Robert Fred
Published: May 2012

Abstract

Elastic and inelastic processes are involved in the propagation of any particular disturbance and the literature on wave propagation is reviewed. A laser interferometer was constructed to resolve the details in the wave structure and which had sufficient sensitivity to resolve the reverberations of the elastic precursor between the free surface and the oncoming plastic wave. This non‐contacting surface technique offers the advantage of excellent time resolution (∼5 nanoseconds) and space resolution (0.06‐micron) together with small surface area requirements. The stress pulse was generated in either 6061‐T6 aluminum or aluminum oxide with an exploding foil driven Mylar flyer. A stress wave analyzing program (SWAP) was written in Fortran to compute stress time histories in problems involving one‐dimensional strain configurations in elastic, plastic, and hydrodynamic materials. SWAP uses the method of characteristics approach and represents all stress wave shapes by a series of shock waves. A sufficient amount of experimental and theoretical evidence has now been gathered to support the assertion that the critical normal fracture stress criterion for spall must be at least extended, if not totally revised. There is a stress‐dependent fracture delay time which decreases with in‐ceasing stress, not only because more cracks are nucleated, but also because the acceleration of the crack tips increases. Similarly ductile materials require more time to fracture than brittle materials because stresses are relieved not only by fracture but also by flow. The results provide additional evidence for the necessity of including a time‐related parameter in the spall criterion.
INSTRUMENTATION IN TOXICOLOGY: ASSESSING TOXIC MATERIALS AND PRODUCTS IN THE BODY*
Authors: Kay Kingsley
Published: May 2012

Abstract

Some examples of potentially toxic materials occurring in occupational or general environmental situations are given in table 1 to illustrate the magnitude of the toxicological assessment problem on which current health protection is based. The field of drugs, especially the narcotics and hallucinogens, is another area of toxicology that has assumed recent importance.

The specific requirements in assessing toxic materials and their breakdown products in the body are: (a) to establish the concentration levels and to follow the course of the metabolism. (b) to identify target organs and measure functional changes or tissue damage in the target organs.

Important advances in the knowledge needed to meet these two requirements have been made possible by the technical ingenuity of instrument designers. Some instruments are available that permit aspects of toxicological assessment to be realized on intact body organs. Where this ideal methodology is not possible, blood samples may be drawn and small samples of tissue from selected organs may be secured by needle biopsy without harming the individuals. This material may be examined histologically by microscopy, and chemically with a variety of analytical instruments. Then there are the main body effluents—urine, feces, and exhaled air, which can also be examined in a variety of ways.
INSULIN, ADENYL CYCLATE, IONS, AND THE HEART
Authors: Kones Richard J.
Published: May 2012

Abstract

Insulin accelerates the entry of glucose and amino acids into muscle cells by acting upon the carrier‐facilitated transport mechanism. For glucose, this process is passive and leads to equilibration of intracellular and extracellular concentrations. In heart muscle, glucose transport is a rate‐limiting step for glucose uptake. During hypoxia and ischemia the heart turns to anaerobic glycolysis for energy production, and therefore maximal glucose transport becomes important. Insulin is necessary to insure proper protein synthesis, probably acting at the level of membrane‐bound polyribosomes. However, during myocardial hypoxia, insulin alone cannot restore the associated depression in protein synthesis.

Although insulin effects net and rapid potassium uptake by the heart cell and hyperpolarizes the cell, the change in the ratio of intracellular to extracellular activities of potassium is not the primary action of insulin. Rather, an insulin‐induced configurational change in the plasma membrane could simultaneously account for the effects of insulin on sodium and potassium permeability and the action on facilitated transport. Intracellular levels of adenyl cyclate are reduced by insulin in extracardiac tissues perhaps through inhibition of adenyl cyclase or stimulation of phosphodiesterase, but convincing evidence that this occurs in the heart is lacking.

Insulin secretion is depressed in patients with heart disease in proportion to the reduction in cardiac index sustained. Since the ischemic heart is dependent upon glucose as the major fuel, insulin lack may deprive the heart of adequate substrate availability under these conditions. The multivalent actions of insulin on the heart cell are especially important in view of the resurgence of interest in glucose‐insulin‐potassium therapy for the treatment of clinical heart disease.
SYSTEM ENGINEERING APPLIED TO HEALTH CARE*
Authors: de Haas E.
Published: May 2012

An early warning system for the major chronic diseases is proposed. Initial calculations made for New Jersey show that such a system eventually could save about 6000 lives per year in the state and avoid an equal number of disabilities. The backbone would be 30 Preventive Health Screening Stations, through which eventually 1 500 000 persons per year would pass. Annual operating costs of 40–50 million dollars would be more than covered by decreases in life insurance, health insurance, and welfare claims.
INSTRUMENTATION FOR WORK PHYSIOLOGY*
Authors: Kamon Eliezer
Published: May 2012

The industrial community has recently recognized the needs for close evaluation of the workers' physiological strain on the job. Consequently, a new era is forthcoming in which the challenge regarding the design and sensibility of the instruments will involve portability, direct reading of data, fast response, and simple analysis procedure. Instruments for cardiopulmonary and thermoregulatory responses were discussed in light of the widely used measurements of steady‐state responses and the future needs to measure transient responses.
‘Autonomic conflict’: a different way to die during cold water immersion?
Authors: Shattock Michael J. , Tipton Michael J.
Published: May 2012

Abstract  Cold water submersion can induce a high incidence of cardiac arrhythmias in healthy volunteers. Submersion and the release of breath holding can activate two powerful and antagonistic responses: the ‘cold shock response’ and the ‘diving response’. The former involves the activation of a sympathetically driven tachycardia while the latter promotes a parasympathetically mediated bradycardia. We propose that the strong and simultaneous activation of the two limbs of the autonomic nervous system (‘autonomic conflict’) may account for these arrhythmias and may, in some vulnerable individuals, be responsible for deaths that have previously wrongly been ascribed to drowning or hypothermia. In this review, we consider the evidence supporting this claim and also hypothesise that other environmental triggers may induce autonomic conflict and this may be more widely responsible for sudden death in individuals with other predisposing conditions.
Categorized or continuous? Strength of an association – and linear regression
Authors: Drummond Gordon B. , Vowler Sarah L.
Published: May 2012

Key points 

Correlation and regression are used with continuous variables

Plot the variables in correlation and regression relationships to aid interpretation

An association between two discrete measurements is assessed by correlation

Regression describes and quantifies a relationship between an independent factor and a dependent variable; prediction is also possible

Few biological relationships are truly linear

Regression can be distorted by outlying values

Absence of a linear regression does not mean a relationship is not present

Regression is very frequently misused and mis‐applied
Photoresponse of PbS nanoparticles–quaterthiophene films prepared by gaseous deposition as probed by XPS
Authors: Majeski Michael W. , Pleticha F. Douglas , Bolotin Igor L. , Hanley Luke , Yilmaz Eda , Suzer Sefik
Published: May 2012

Semiconducting lead sulfide (PbS) nanoparticles were cluster beam deposited into evaporated quaterthiophene (4T) organic films, which in some cases were additionally modified by simultaneous 50 eV acetylene ion bombardment. Surface chemistry of these nanocomposite films was first examined using standard x-ray photoelectron spectroscopy (XPS). XPS was also used to probe photoinduced shifts in peak binding energies upon illumination with a continuous wave green laser and the magnitudes of these peak shifts were interpreted as changes in relative photoconductivity. The four types of films examined all displayed photoconductivity: 4T only, 4T with acetylene ions, 4T with PbS nanoparticles, and 4T with both PbS nanoparticles and acetylene ions. Furthermore, the ion-modified films displayed higher photoconductivity, which was consistent with enhanced bonding within the 4T organic matrix and between 4T and PbS nanoparticles. PbS nanoparticles displayed higher photoconductivity than the 4T component, regardless of ion modification.
Reduced risk trajectory planning in image‐guided keyhole neurosurgery
Authors: Shamir Reuben R. , Joskowicz Leo , Tamir Idit , Dabool Elad , Pertman Lihi , Ben‐Ami Adam , Shoshan Yigal
Published: May 2012

Purpose:

The authors present and evaluate a new preoperative planning method and computer software designed to reduce the risk of candidate trajectories for straight rigid tool insertion in image‐guided keyhole neurosurgery.

Methods:

Trajectories are computed based on the surgeon‐defined target and a candidate entry point area on the outer head surface on preoperative CT/MRI scans. A multiparameter risk card provides an estimate of the risk of each trajectory according to its proximity to critical brain structures. Candidate entry points in the outer head surface areas are then color‐coded and displayed in 3D to facilitate selection of the most adequate point. The surgeon then defines and/or revised the insertion trajectory using an interactive 3D visualization of surrounding structures. A safety zone around the selected trajectory is also computed to visualize the expected worst‐case deviation from the planned insertion trajectory based on tool placement errors in previous surgeries.

Results:

A retrospective comparative study for ten selected targets on MRI head scans for eight patients showed a significant reduction in insertion trajectory risk. Using the authors' method, trajectories longer than 30 mm were an average of 2.6 mm further from blood vessels compared to the conventional manual method. Average planning times were 8.4 and 5.9 min for the conventional technique and the authors' method, respectively. Neurosurgeons reported improved understanding of possible risks and spatial relations for the trajectory and patient anatomy.

Conclusions:

The suggested method may result in safer trajectories, shorter preoperative planning time, and improved understanding of risks and possible complications in keyhole neurosurgery.
Artemisinin-Derived Dimer Diphenyl Phosphate Is an Irreversible Inhibitor of Human Cytomegalovirus Replication
Authors: He Ran , Park Kyoungsook , Cai Hongyi , Kapoor Arun , Forman Michael , Mott Bryan , Posner Gary H. , Arav-Boger Ravit
Published: May 2012

We previously reported that among a series of artemisinin-derived monomers and dimers, dimer diphenyl phosphate (838) was the most potent inhibitor of human cytomegalovirus (CMV) replication. Our continued investigation of a prototypic artemisinin monomer (artesunate [AS]) and dimer (838) now reveals that both compounds have specific activity against CMV but do not inhibit lytic replication of human herpesvirus 1 or 2 or Epstein-Barr virus. AS and 838 inhibited CMV replication during the first 24 h of the virus replication cycle, earlier than the time of ganciclovir (GCV) activities and prior to DNA synthesis. Neither compound inhibited virus entry. Quantification of DNA replication and virus yield revealed a similar level of inhibition by GCV, but AS and 838 had a 10-fold-higher inhibition of virus yield than of DNA replication, suggesting that artemisinins could inhibit CMV through multiple steps: a predominant early inhibition and possibly an additional step following DNA replication. During the strong early CMV inhibition, the transcription of immediate-early genes was not significantly downregulated, and viral protein expression was reduced only after 48 h. AS and GCV were reversible CMV inhibitors, but the inhibition of CMV replication by 838 was irreversible. Combinations of GCV and 838 as well as GCV and AS were highly synergistic. Finally, treatment with 838, but not AS, prior to CMV infection demonstrated strong anti-CMV activity. These findings illustrate the unique activities of dimer 838, including early and irreversible CMV inhibition, possibly by tight binding to its target.
RmtF, a New Member of the Aminoglycoside Resistance 16S rRNA N7 G1405 Methyltransferase Family
Authors: Galimand Marc , Courvalin Patrice , Lambert Thierry
Published: May 2012

Multidrug-resistant clinical isolate
Klebsiella pneumoniae
BM4686 was highly resistant to 4,6-disubstituted 2-deoxystreptamines and to fortimicin. Resistance was due to the presence, on the 40-kb non-self-transferable plasmid pIP849, of the
rmtF
gene which was cotranscribed with the upstream
aac
(
6
′)-
Ib
gene. The deduced RmtF protein had 25 to 46% identity with members of the N7 G1405 family of aminoglycoside resistance 16S rRNA methyltransferases.
The relationship of femoral neck shaft angle and adiposity to greater trochanteric pain syndrome in women. A case control morphology and anthropometric study
Authors: Fearon AM , Stephens S , Cook JL , Smith PN , Neeman T , Cormick W , Scarvell JM
Published: May 2012

Objective

To evaluate if pelvic or hip width predisposed women to developing greater trochanteric pain syndrome (GTPS).

Design

Prospective case control study.

Participants

Four groups were included in the study: those gluteal tendon reconstructions (n=31, GTR), those with conservatively managed GTPS (n=29), those with hip osteoarthritis (n=20, OA) and 22 asymptomatic participants (ASC).

Methods

Anterior-posterior pelvic x-rays were evaluated for femoral neck shaft angle; acetabular index, and width at the lateral acetabulum, and the superior and lateral aspects of the greater trochanter. Body mass index, and waist, hip and greater trochanter girth were measured. Data were analysed using a one-way analysis of variance (ANOVA; posthoc Scheffe analysis), then multivariate analysis.

Results

The GTR group had a lower femoral neck shaft angle than the other groups (p=0.007). The OR (95% CI) of having a neck shaft angle of less than 134°, relative to the ASC group: GTR=3.33 (1.26 to 8.85); GTPS=1.4 (0.52 to 3.75); OA=0.85 (0.28 to 2.61). The OR of GTR relative to GTPS was 2.4 (1.01 to 5.6). No group difference was found for acetabular or greater trochanter width. Greater trochanter girth produced the only anthropometric group difference (mean (95% CI) in cm) GTR=103.8 (100.3 to 107.3), GTPS=105.9 (100.2 to 111.6), OA=100.3 (97.7 to 103.9), ASC=99.1 (94.7 to 103.5), (ANOVA: p=0.036). Multivariate analysis confirmed adiposity is associated with GTPS.

Conclusion

A lower neck shaft angle is a risk factor for, and adiposity is associated with, GTPS in women.
Changes in knee joint biomechanics following balance and technique training and a season of Australian football
Authors: Donnelly Cyril J , Elliott Bruce C , Doyle Tim L A , Finch Caroline F , Dempsey Alasdair R , Lloyd David G
Published: May 2012

Purpose

Determine if balance and technique training (BTT) implemented adjunct to normal Australian football (AF) training reduces external knee loading during sidestepping. Additionally, the authors determined if an athlete's knee joint kinematics and kinetics change over a season of AF.

Methodology

Eight amateur-level AF clubs (n=1,001 males) volunteered to participate in either 28 weeks of BTT or a ‘sham’ training (ST) adjunct to their normal preseason and regular training. A subset of 34 athletes (BTT, n=20; ST, n=14) were recruited for biomechanical testing in weeks 1–7 and 18–25 of the 28-week training intervention. During biomechanical testing, participants completed a series running, preplanned (PpSS) and unplanned sidestepping (UnSS) tasks. A linear mixed model (α=0.05) was used to determine if knee kinematics and peak moments during PpSS and UnSS were influenced by BTT and/or a season of AF.

Results

Both training groups significantly (p=0.025) decreased their peak internal-rotation knee moments during PpSS, and significantly (p=0.022) increased their peak valgus knee moments during UnSS following their respective training interventions.

Conclusions

BTT was not effective in changing an athlete's knee joint biomechanics during sidestepping when conducted in ‘real-world’ training environments. Following normal AF training, the players had different changes to their knee joint biomechanics during both preplanned and unplanned sidestepping. When performing an unplanned sidestepping task in the latter half of a playing season, athletes are at an increased risk of ACL injury. The authors therefore recommend both sidestepping tasks are performed during biomechanical testing when assessing the effectiveness of prophylactic training protocols.
Unrecognised ringside concussive injury in amateur boxers
Authors: Moriarity James M , Pietrzak Robert H , Kutcher Jeffrey S , Clausen Margaretha Helen , McAward Kevin , Darby David G
Published: May 2012

Objectives

Concussion is common in contact sports such as boxing. Diagnosis of concussion depends on symptom report or recognition of clinical features, and true incidence may be underestimated. Persistent morbidity is a possible risk of repeated or unrecognised concussion. This study aimed to evaluate pre and postbout cognitive performance in motivated amateur boxers in order to detect objective evidence of unrecognised cognitive impairment suggestive of concussive injury.

Methods

The study employed a prospective and observational design. Participants were amateur boxers who won at least one bout in a single elimination competition. Optimal preparticipation performance using a computerised cognitive assessment tool (CCAT, Axon Sports) and no significant deterioration in cognitive performance within 24 h postbout were required to compete. All boxers were screened for clinical evidence of concussion by a ringside physician.

Results

Of approximately 200 competing boxers, 96 were eligible having won at least one of the total 160 bouts. Mean age was 21.3 (SD 1.9) years (range 18.5–29.7). Of these, 17 (10.6%) failed their first postbout CCAT, with 12 (71%) passing a repeat test. Of the five remaining boxers, there were two boxers (1.3% of bouts) not suspected of a concussion after their bouts, who showed evolving slowing in cognitive performance typical of a concussion.

Conclusions

Cognitive impairment, as detected by subtle deterioration in reaction time measures, can occur in amateur boxers postbout that is not recognised at ringside. Although the vast majority of bouts were conducted safely, unrecognised injury may occur and be detectable using objective computerised cognitive assessment.