bluuebunny/crossref_metadata_2025 huggingface dataset:
How Do Disadvantaged Parents View Tensions in Their Relationships? Insights for Relationship Longevity Among At‐Risk Couples*
Authors: Waller Maureen R.
Published: March 2008

Abstract: Drawing on longitudinal, qualitative interviews with parents in the Fragile Families Study, this paper examines the narrative frames through which partners in stable and unstable unions viewed tensions over economic issues, domestic responsibilities, personal problems, communication, trust, and their family and social networks. These interviews suggest that parents in stable unions framed tensions as manageable within the context of a relationship they perceived to be moving forward, whereas those in unstable unions viewed tensions as intolerable in relationships they considered volatile. Three years later, parents’ narrative frames generally guided their decisions about maintaining or dissolving relationship, but some parents changed their interpretations in response to unexpected positive or negative events, with important implications for union longevity.
Virulence of the entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae to sweet potato weevil Cylas puncticollis and effects on fecundity and egg viability
Authors: Ondiaka S. , Maniania N.K. , Nyamasyo G.H.N. , Nderitu J.H.
Published: March 2008

The virulence of eight isolates of Metarhizium anisopliae and four isolates of Beauveria bassiana (Ascomycota: Hypocreales) to adult Cylas puncticollis (Coleoptera: Curculionidae) was tested in the laboratory. Insects were sprayed with a standard concentration of 1.0 × 107 conidia mL−1 using Burgerjon’s spray tower. All the isolates tested were pathogenic to C. puncticollis. Mortality varied between 77.5% and 84.2% with isolates of B. bassiana and between 62.5% and 89.2% with isolates of M. anisopliae, 26 days post‐treatment. The lethal time to 50% mortality for the 12 isolates varied between 9.7 and 18.5 days. Four isolates, M. anisopliae International Centre of Insect Physiology and Ecology (ICIPE) 18 and ICIPE 62 and B. bassiana ICIPE 275 and ICIPE 114 were selected for dose–response mortality [lethal concentration to 50% mortality (LC50)] bioassays. Five concentrations (1.0 × 106, 3.0 × 106, 1.0 × 107, 3.0 × 107 and 1.0 × 108 conidia mL−1) of both fungal species were used. B. bassiana ICIPE 275 was the most active isolate with LC50 value of 0.7 × 106 conidia mL−1. The effect of fungal infection on feeding, fecundity and egg viability of C. puncticollis adult females was also investigated under laboratory conditions. M. anisopliae isolate ICIPE 18 and B. bassiana isolate ICIPE 114 were tested for feeding experiment using six concentrations (0, 1.0 × 106, 3.0 × 106, 1.0 × 107, 3.0 × 107 and 1.0 × 108 conidia mL−1). For reproduction potential (fecundity and egg viability) bioassays, five concentrations (0, 1.0 × 106, 3.0 × 106, 1.0 × 107 and 3.0 × 107 conidia mL−1) of M. anisopliae isolate ICIPE 18 were used. Adult sweet potato weevils (SPWs) treated with M. anisopliae at the concentrations of 3.0 × 107 and 1.0 × 108 conidia mL−1 consumed significantly less food than weevils in the control and B. bassiana treatments at all the concentrations, except at the higher concentration of 1.0 × 108 conidia mL−1, 14 days post‐treatment. Female weevils in the control treatments laid more eggs than fungus‐treated females. Percentage egg viability differences between controls and fungus treatments were significant at all the concentrations tested, 10 days post‐treatment. These results show that B. bassiana and M. anisopliae are pathogenic to SPWs and infection can reduce feeding, fecundity and egg viability.
Discovery of X-ray pulsations from the HMXB source AXJ1749.1-2733
Authors: Karasev D. I. , Tsygankov S. S. , Lutovinov A. A.
Published: March 2008

We are reporting the discovery of X-ray pulsations from the source AXJ1749.1-2733 with the period of ∼132 s based on the XMM–Newton data obtained in 2007 March. The observed pulse profile has a double-peaked structure with the pulse fraction of about 25–30 per cent in the 3–10 keV energy band. We have also found that a periodicity with practically the same period has been detected from the source by the IBIS telescope onboard the INTEGRAL observatory during an outburst on 2003 September 9 in the 20–50 keV energy band. Due to the double-peaked pulse profile, there is an additional peak on both periodograms of ∼66 s; therefore we have also investigated the possibility that the last value is the true pulse period. The source spectrum obtained by the XMM–Newton observatory in the soft energy band is being heavily absorbed (NH≃ 2 × 1023 cm−2) due to a strong intrinsic absorption in the binary system that leads to the conclusion that AXJ1749.1-2733 is a new transient X-ray pulsar in the high-mass X-ray binary system.
The dark energy equation of state
Authors: Usmani A. A. , Ghosh P. P. , Mukhopadhyay Utpal , Ray P. C. , Ray Saibal
Published: March 2008

We perform a study of cosmic evolution with an equation of state parameter by selecting a phenomenological Λ model of the form, . This simple proposition explains both linearly expanding and inflationary universes with a single set of equation. We note that the inflation leads to a scaling in the equation of state parameter, ω(t), and hence in equation of state. In this approach, one of its two parameters has been pin pointed and the other has been delineated. It has been possible to show a connection between dark energy and Higgs–Boson.
Leadership Structure and Corporate Governance in Switzerland*
Authors: Schmid Markus M. , Zimmermann Heinz
Published: March 2008

The question of whether the CEO should also serve as chairman of the board continues to be a controversial issue in corporate governance. While “agency cost” arguments would lead one to advocate separation of the top decision‐making and control functions, there are efficiency and coordination arguments for vesting the powers of the CEO and chair in the same person. And helping to keep the controversy alive, the empirical evidence on U.S. companies is inconclusive, with no clear loss of value associated with having combined CEO/chairmen.

The authors use their recent research on Swiss companies, for which separation of the CEO and chair has long been the rule, to shed light on whether one leadership structure clearly dominates. But like most previous studies of U.S. companies, the authors report no evidence of a systematic difference in valuation between companies with combined and those with dual leadership. The authors also investigated whether companies with CEO‐chairmen use other governance mechanisms to counteract potential agency problems associated with giving the CEO effective control. Consistent with this hypothesis, the authors report that CEO/chairmen tend to have larger percentage ownership than CEOs who are not chairmen, but at the same time they find that the value of the firm appears to rise with increases in CEO equity holdings up to a certain point—around 40–50%— and then declines with further increases above that point. The suggestion here is that the potential for agency costs associated with combining the two leadership functions appears to be managed by providing larger—though not too large—equity incentives for CEO/chairmen.

Finally, the authors investigated whether firm value is significantly related to firm‐level corporate governance as measured by a broad survey‐based index for a representative sample of Swiss firms. The results show a positive and significant relationship between the governance index and firm value—one that proves robust after controlling for a series of other governance mechanisms related to ownership structure and board characteristics as well as the possible “endogeneity” of these mechanisms.
LOW SELF‐CONTROL, ROUTINE ACTIVITIES, AND FRAUD VICTIMIZATION*
Authors: HOLTFRETER KRISTY , REISIG MICHAEL D. , PRATT TRAVIS C.
Published: March 2008

Recent research has used both routine activity/lifestyle frameworks and self‐control theory to explain victimization. Thus far, combined tests of these theories have focused on offending populations and street crime victimization. Whether these frameworks also explain exposure to and likelihood of nonviolent victimization (e.g., fraud) in general‐population samples remains an open empirical question. Building on prior work, we assess the independent effects of routine consumer activities (i.e., remote purchasing) and low self‐control on the likelihood of fraud targeting and victimization. Using a representative sample of 922 adults from a statewide survey in Florida, the results confirm our expectation that remote‐purchasing activities increase consumers' risk of being targeted for fraud. Low self‐control has no effect on whether consumers are targeted, but it does significantly increase the likelihood of fraud victimization.
THE RELEVANCE OF PEACE TO STUDIES OF DRUG MARKET VIOLENCE*
Authors: JACQUES SCOTT , WRIGHT RICHARD
Published: March 2008

Goldstein's (1985) concept of systemic violence has contributed substantially to criminological thought and research, but its power can be enhanced by connecting it to a broader typology of social life: the resource exchange—social control typology. That typology connects systemic violence logically with two important yet neglected forms of drug market behavior: peaceful resource exchange and peaceful social control. This article, which is based on 50 in‐depth interviews with individuals involved actively or recently in drug selling, describes the various forms of violent and nonviolent resource exchange and social control in illicit drug markets, stating them in quantitative terms that are conceptually distinct and empirically observable. We conclude by discussing 1) the implications of peaceful behavior for a fuller understanding of violence and 2) the relevance of the resource exchange‐social control typology to criminological theory and research.
A LIFE‐COURSE PERSPECTIVE ON SPIRITUALITY AND DESISTANCE FROM CRIME*
Authors: GIORDANO PEGGY C. , LONGMORE MONICA A. , SCHROEDER RYAN D. , SEFFRIN PATRICK M.
Published: March 2008

Spirituality is a component of many drug and alcohol treatment strategies, and faith‐based programming is also common within prison settings. Yet research on religiosity—crime linkages has often relied on general youth or adult samples or has included a short time line for gauging positive effects. Life‐course researchers focused on serious delinquents, in turn, have often emphasized other factors associated with long‐term crime patterns, such as marital attachment and job stability, or the criminality of the individual's social ties. This study draws on quantitative and qualitative data derived from a long‐term follow‐up of a sample of serious adolescent male and female offenders to explore the role of spirituality and religious participation as influences on adult patterns of criminal involvement (N= 152). The respondents were first interviewed as adolescents, in 1982, and again as adults in 1995 and 2003. Results of longitudinal analyses that take into account self‐report and incarceration histories at both time periods do not reveal a significant association between these indices of religiosity and the likelihood of evidencing a pattern of sustained desistance. Our analysis of indepth life‐history interviews conducted with most respondents over these two time periods and 41 additional interviews focused specifically on spirituality and religion are used to explore in more detail the promise and challenges associated with relying on religiosity as a catalyst for sustained behavior change.
ON THE RELATIONSHIP BETWEEN FAMILY STRUCTURE AND ANTISOCIAL BEHAVIOR: PARENTAL COHABITATION AND BLENDED HOUSEHOLDS*
Authors: APEL ROBERT , KAUKINEN CATHERINE
Published: March 2008

In the last several decades, the American family has undergone considerable change, with less than half of all adolescents residing with two married biological parents. Using the National Longitudinal Survey of Youth 1997, we construct an elaborate measure of family structure and find considerable heterogeneity in the risk of antisocial and delinquent behavior among groups of youth who reside in what are traditionally dichotomized as intact and nonintact families. In particular, we find that youth in “intact” families differ in important ways depending on whether the two biological parents are married or cohabiting and on whether they have children from a previous relationship. In addition, we find that youth who reside with a single biological parent who cohabits with a nonbiological partner exhibit an unusually high rate of antisocial behavior, especially if the custodial parent is the biological father.
Moral Judgment and Moral Neuroscience: Intersections, Definitions, and Issues
Authors: Killen Melanie , Smetana Judith
Published: March 2008

ABSTRACT—
The moral neurosciences are an emerging area of research that has the potential to improve our understanding of the biological basis of morality. Thus far, however, research on moral neuroscience and moral judgment development has proceeded independently and with little interconnection. The current article discusses how morality has been defined and assessed in several new and prominent lines of research in the moral neurosciences and in research over the past 30 years on moral judgment development. It discusses how the 2 lines of research could be better integrated and points to strengths and limitations in the current field. Finally, suggestions are provided for further research.
The Impact of Trafficking on Children: Psychological and Social Policy Perspectives
Authors: Rafferty Yvonne
Published: March 2008

ABSTRACT—
Child trafficking and commercial sexual exploitation (CSE) are egregious crimes, extreme forms of child maltreatment, and major violations of children’s human rights. Although empirical research is sorely lacking on the impact of such crimes on children’s developmental well‐being, numerous reports describe the physical and emotional trauma, humiliation, violence, degradation associated with treatment as a commodity, and unrelenting fear and abuse. This paper provides an overview of the impact of trafficking and CSE on children and the practical implications of related research in the areas of child maltreatment and victimization. Findings suggest that trafficking and CSE present grave risks to the physical, psychological, spiritual, and social–emotional development of young victims. Implications for psychology and social policy, in terms of prevention and psychosocial rehabilitation for children who have been victimized, are also presented.
Prorenin and (pro)renin receptor: a review of available data from in vitro studies and experimental models in rodents
Authors: Nguyen Geneviève , Danser A. H. Jan
Published: March 2008

The discovery of a (pro)renin receptor [(P)RR] and the introduction of renin inhibitors in the clinic have brought renin and prorenin back into the spotlight. The (P)RR binds both renin and its inactive precursor prorenin, and such binding triggers intracellular signalling that upregulates the expression of profibrotic genes, potentially leading to cardiac and renal fibrosis, growth and remodelling. Simultaneously, binding of renin to the (P)RR increases its angiotensin I‐generating activity, whereas binding of prorenin allows the ‘inactive’ renin precursor to become fully enzymatically active. Therefore, the (pro)renin receptor system could be considered as having two functions, an angiotensin‐independent function related to (P)RR‐induced intracellular signalling and its downstream effects and an angiotensin‐dependent function related to the increased catalytic activity of receptor‐bound (pro)renin. A (P)RR blocker has already been described which blocks both functions, thus preventing diabetic nephropathy, cardiac fibrosis and ocular neovascularization. On‐going experimental studies should now determine which of the two functions plays the more important role in pathological situations. The results of these studies are extremely important in view of the clinical use of renin inhibitors, since it is well known that their administration results in increased levels of both renin and prorenin. Although this rise can be interpreted as evidence of effective renin–angiotensin system blockade, it could also result in increased (P)RR activation.
Design of a High Yielding Photonic Light Delivery System to be Used in Photodynamic Therapy for Esophageal Cancer, With Microwave Antenna Imprinted Balloon Catheter for Oxygen Enhancement
Authors: Premasiri Amaranath , Happawana Gemunu , Evans Gary , Rosen Arye
Published: March 2008

Photodynamic therapy (PDT) is a minimally invasive treatment with high effectiveness in the management of cancer of the upper gastrointestinal tract. A higher mortality rate associated with surgery and the higher morbidity in the older age group both make PDT a better treatment method for the treatment of esophageal cancer [1–3]. However, limitations in the best docimetry protocols performance of PDT are due to ineffectiveness of the light delivery and in the unavailability of sufficient oxygen required for singlet oxygen generation to bring cellular death [4–7]. The Introduction of an inexpensive high power semiconductor diode lasers for the light delivery system makes PDT efficient, low cost and portable [8–10]. However, the metallic water cooling systems used in the existing semiconductor cooling designs make those systems non-flexible and cumbersome in size [9].
Sterile Medical Device Package Development: From Concept to Market
Authors: Montgomery G. Jordan , Troutman Randall J.
Published: March 2008

Developing the packaging system for medical device products is often an after thought in the product development life cycle. The sterile package is a critical part of the device, as the device must be sterile in order to be used; therefore the package provides the device with utility at the point of use. Although the packaging for a medical device is as critical to the device function as the device itself, the process and methods that must be followed to effectively design, develop, and implement a sterile package assembly are established but often misunderstood. Medical device packaging development is directly related to factors associated with the physiological and pathological environment, the development of the device, and regulatory issues surrounding the possible markets of distribution. It is critical that the proper packaging development be applied to a device to ensure that it is both safe and effective.
Development of a Multi-Axis Peripheral Stent Durability/Fatigue Test Instrument
Authors: Anderson S. E. , Schneider B. A. , Graen M. D. , Nesdahl K. , Seeman S. R. , Nickel T. D.
Published: March 2008

Structural failures of metallic stents in peripheral arteries such as the superficial femoral artery (SFA) have challenged industry to devise a suitable mechanical durability/fatigue model to simulate the clinical conditions. Previous mechanical durability testing for stents has consisted of pulsatile fatigue of a straight stent in a straight tube. The stents are distended to diametric levels expected in the target native artery and cycled to duplicate 10 years of simulated life. This is at least 380 million cycles. High speed pulsatile fatigue test instruments have been able to reproduce those distentions at test frequencies of 60 Hz resulting in a simulated 10 year life of less than 90 days.
A New Direct Electron Imaging System for Biomedical Applications
Authors: Li Shengdong , Kleinfelder Stuart
Published: March 2008

High resolution electron imaging of biological assemblies such as proteins, viruses, and cells are important for biomedical diagnosis and drug discovery. We report on the design of a new CMOS direct-detection camera system for electron imaging. The active pixel sensor array includes 512 by 550 pixels, each 5 by 5 μm in size, with a ~8 μm epitaxial layer to achieve an effective fill factor of 100%. Spatial resolution of 2.3 μm for a single incident e- has been measured. A sample image of a mouse’s muscle cell is presented.
Mortality of white spruce during a spruce beetle outbreak on the Kenai Peninsula in Alaska
Authors: Werner Richard A. , Holsten Edward H.
Published: March 2008

White spruce (Piceaglauca (Moench) Voss) stands in the Resurrection Creek watershed in south-central Alaska were infested by spruce bettles, Dendroctonusrufipennis Kirby, between 1974 and 1975. Thirty permanent plots were established within the infested area in 1976 to evaluate the immediate and long-term impact on white spruce stands. Plots were revisited annually for 5 years. Between 1976 and 1980, 29% of all white spruce was killed by spruce beetles. This loss accounted for 59% of the commercial white spruce volume in the watershed. Mortality was greatest in the larger diameter classes during the early part of the infestation, but smaller diameter trees were subsequently attacked as the number of noninfested trees declined. The impact of spruce beetles on structure and species composition of white spruce stands is given along with a discussion of management implications.
Litter decomposition in coastal hemlock stands: impact of nitrogen fertilizers on decay rates
Authors: Gill Ranjit S. , Lavender Denis P.
Published: March 2008

Urea, gypsum-coated urea, and calcium nitrate fertilizers differentially affected indigenous rates of litter decomposition on the forest floor for coastal stands of western hemlock (Tsugaheterophylla (Raf.) Sarg.). These differences were most pronounced during the first 6 months after fertilization. Urea and gypsum-coated urea both stimulated the rates of litter decomposition, although the effect of gypsum-coated urea was more gradual. In contrast, calcium nitrate somewhat retarded existing decomposition rates during the first 6 months; after 12 months, it had little or no impact. The significant (P < 0.05) positive correlation of percentage of lignin in litter with time renders it an important qualitative measure of decomposition rates in studies utilizing litter bags.
Na–Picotransporter type I activity causes a transient intracellular alkalinization during ATP depletion in rabbit medullary thick ascending limb cells
Authors: Jans F. , Ameloot M. , Wouters P. , Steels P.
Published: March 2008

The cellular pathophysiology of renal ischemia–reperfusion injury was investigated in primary cell cultures from rabbit medullary thick ascending limb (MTAL). Metabolic inhibition (MI) was achieved with cyanide and 2-deoxyglucose. Sixty minutes of MI caused a profound but reversible decrease in intracellular concentration of ATP ([ATP]i). Intracellular pH (pHi) first decreased after initiation of MI, followed by a transient alkalinization. When [ATP]ireached its lowest value (<1% of control), the cells slowly acidified to reach a stable pHiof 6.92 after 50 min of MI. In the presence of EIPA (10 µmol/L), the pattern of changes in pHiwas unchanged and acidification was not increased, indicating that the Na+/H+exchangers were inactive during ATP depletion. When inorganic phosphate (Pi) or Na+was omitted from the apical solutions during MI, the transient alkalinization was no longer observed and the cytosol slowly acidified. Experiments on Na+-dependent alkalinizations revealed the presence of a Na–Picotransporter in the apical cell membrane. With indirect immunofluorescence, the Na–Picotransporter expressed in these primary cell cultures could be identified as Na–Pitype I. Although the exact physiological role of Na–Pitype I still is unresolved, these experiments demonstrate that apical Na–Pitype I activity is increased at the onset of ATP depletion in MTAL cells.
Evidence that the etiology of the syndrome containing type 2 diabetes mellitus results from abnormal magnesium metabolism
Authors: Wells Ibert C.
Published: March 2008

Evidence is reviewed supporting the presence of an inherited structural defect in the plasma membranes of somatic cells of humans who have type 2 diabetes mellitus and sodium-sensitive essential hypertension. This magnesium-binding defect (MgBD) consists of a decreased content of tightly bound Mg2+ion in the cell membrane and limits the amount of Mg2+that enters the cell, some of which combines with ATP4–, produced by the cell, to form MgATP2–, the currency of metabolic energy. Consequently, in both prediabetes and overt diabetes, the intracellular concentration of the interdependent Mg2+and MgATP2–ions is significantly less than normal. These 2 ions are required as cofactors and (or) substrates for some 300 enzyme systems in human metabolism, many of which are involved with insulin. Thus the decreased activities of particular ones of these enzyme systems due to the decreased intracellular [Mg2+] and its dependent [MgATP2–] are responsible for (i) insulin resistance and (ii) decreased insulin secretion and (or) production, the 2 pathophysiological processes required for the occurrence of type 2 diabetes mellitus. These 2 processes can account for all of the morbid symptoms associated with this disease. Thus, the decreased intracellular concentration of the interdependent Mg2+and MgATP2–ions constitutes the etiology of genetic predisposition to type 2 diabetes mellitus and can be corrected by 2 identified peptide Mg2+-binding promoters that are derived from the carboxyl terminal of the tachykinin substance P and occur in normal blood plasma. Decreased intracellular [Mg2+] and [MgATP2–] can also result from a dietary deficiency of magnesium or from an abnormal accumulation of saturated fatty acids in cell membranes, which inhibits the entrance of Mg2+into the cell; thus it is also the etiology not only of diabetes caused by magnesium deficiency, but also of the “lipotoxic” type 2 diabetes mellitus. Although these pathologies cannot be corrected by the Mg2+-binding promoters, they can be corrected, respectively, by dietary magnesium supplementation or by exercise plus dietary caloric and lipid restriction. Theoretically, the disease syndrome containing type 2 diabetes mellitus may involve approximately 30% of the population.
Altered expression of epithelial junctional proteins in atopic asthma: possible role in inflammation
Authors: de Boer W.I. , Sharma H.S. , Baelemans S.M.I. , Hoogsteden H.C. , Lambrecht B.N. , Braunstahl G.J.
Published: March 2008

Epithelial cells form a tight barrier against environmental stimuli via tight junctions (TJs) and adherence junctions (AJs). Defects in TJ and AJ proteins may cause changes in epithelial morphology and integrity and potentially lead to faster trafficking of inflammatory cells through the epithelium. Bronchial epithelial fragility has been reported in asthmatic patients, but little is known about the expression of TJ and AJ proteins in asthma. We studied epithelial expression of zonula occludens-1 (ZO-1) and AJ proteins E-cadherin, α-catenin, and β-catenin in bronchial biopsies from nonatopic nonasthmatic (healthy) subjects (n = 14), and stable atopic asthmatic subjects (n = 22) at baseline conditions. Immunostaining for these proteins was semi-quantified for separate cellular compartments. E-cadherin, α-catenin and β-catenin were present in the cellular membrane and less in the cytoplasm. Only β-catenin was present in the nucleus in agreement with its potential function as transcription factor. ZO-1 was present in the apicolateral membrane of superficial cells. α-Catenin expression was significantly lower in subjects with asthma than without and correlated inversely with numbers of eosinophils within the epithelium. ZO-1 and E-cadherin expression were significantly lower in asthmatic than in nonasthmatic subjects. Expression of β-catenin was not different. Our results suggest that the lower epithelial α-catenin, E-cadherin and (or) ZO-1 expression in patients with atopic asthma contributes to a defective airway epithelial barrier and a higher influx of eosinophils in the epithelium.
Late protective effect of pharmacological preconditioning with total flavones of rhododendra against myocardial ischemia–reperfusion injury
Authors: Zhang Jian-Hua , Chen Zhi-Wu , Wu Zheng
Published: March 2008

The aim of the present study was to investigate the protective effect of total flavones of rhododendra (TFR) pharmacological preconditioning against myocardial ischemia–reperfusion (I/R) injury and its probable mechanisms in rats. Rat myocardial I/R injury was induced by ligating and untying the left anterior descending coronary artery. Male Sprague–Dawley rats were anesthetized and the chests were opened. All animals were subjected to 30 min of occlusion and 1 h of reperfusion. Twenty-four hours before the 30-minute occlusion, rats received 3 cycles of 5 min intravenous perfusion of TFR (10, 20, 40 mg/kg) or morphine hydrochloride (0.3 mg/kg) or normal saline interspersed with drug-free periods. Changes in the ST segment of ECG, the content of cardiac troponin I (cTnI), malondialdehyde (MDA), and nitric oxide (NO), and the activity of superoxide dismutase (SOD), lactate dehydrogenase (LDH), creatine phosphokinase (CK), and nitric oxide synthase (NOS) in serum were measured. Infarct size (IS), as a percentage of the area at risk (AAR), was determined by TTC staining. The expression of inducible nitric oxide synthase (iNOS) mRNA in rat myocardium was detected by RT-PCR and the expression of iNOS protein was detected by Western blot. Pretreatment with TFR (10, 20, 40 mg/kg) markedly inhibited I/R-induced ST segment elevation of ECG. TFR (20, 40 mg/kg) pretreatment decreased I/R-induced IS/AAR, markedly inhibited the increase of MDA content and the activity of CK and LDH, and also significantly inhibited the decline of NO content and the activity of NOS and SOD in serum. TFR (40 mg/kg) preconditioning significantly inhibited the increase of serum cTnI induced by I/R injury and increased the expression of iNOS both at mRNA and protein levels in rat myocardium. Our findings indicate that TFR preconditioning has a protective effect against myocardial I/R injury in rats. The cardioprotection involves the stimulation of NO release and the inhibition of lipid peroxidation.
Can lizard richness be driven by termite diversity? Insights from the Brazilian Cerrado
Authors: Costa G. C. , Colli G. R. , Constantino R.
Published: March 2008

We test predictions of the Morton and James hypothesis, which states that high termite diversity promotes high lizard diversity. We explore consumption of termites by lizards in the Brazilian Cerrado, a system that shares many similarites with arid Australia whose fauna formed the basis for the original hypothesis. We found that Cerrado lizards prey heavily on termites. Several species had >40% of their diet consisting of termites, some species reached up to 80%. However, lizards prey on termites independently of their diversity in the environment and do not show niche segregation in relation to termite resource. Hence, our results in the Cerrado do not support the hypothesis that termite diversity can promote lizard diversity. The diets of Cerrado lizards have a high proportion of termites; however, the diets of desert lizards from the Australian and the Kalahari deserts have a much higher proportion of termites when compared with those from the Cerrado and the Amazon. Differences in termite consumption by lizards across ecosystems do not seem to be related to local termite diversity. We hypothesize that overall prey availability can explain this pattern. Several arthropod groups are abundant in the Cerrado and the Amazon. In deserts, other prey types may be less abundant; therefore, termites may be the best available resource.
Growing with kin does not bring benefits to tadpoles in a genetically impoverished amphibian population
Authors: Orizaola Germán , Laurila Anssi
Published: March 2008

The effect of intraspecific competition can be modified through the interaction with genetic relatedness among the competing individuals. Theory of kin selection predicts that organisms should modify their behaviour to increase the fitness of their relatives and consequently their inclusive fitness. However, in populations with low genetic variation, the recognition of kin and nonkin individuals could be compromised. In this study, we tested the influence of density and relatedness on larval development in a genetically impoverished population of the pool frog ( Rana lessonae Camerano, 1882), exposing individuals from four families to two densities and to competition by full-sibling and nonkin larvae. Larvae in high-density treatment were smaller than those in low-density treatment. No effect of kin, or interaction between density and kin, was detected. However, significant differences were detected in body size among the families and high heritability for size was found in both densities. Lack of variation in recognition alleles may explain the lack of kin effects on growth, whereas variation has been maintained in life-history traits either owing to their polygenic inheritance or owing to maternal effects.
Behavioural plasticity in variable environments
Authors: Komers Petr E.
Published: March 2008

The plasticity of behaviour consists of an array of behavioural responses to varying environmental conditions. It is widely predicted that the range of behavioural responses will increase with environmental variability. According to this prediction, the slopes of a response curve representing behavioural plasticity would be identical in environments with different variability. However, the range of behaviours can also increase with the slope of the curve, so that in a given range of environments, the plasticity of behaviour would vary. For example, where two environments are similar in terms of resource availability, the costs of exploiting the resource may differ. An improved ability to assess costs and benefits is predicted to increase behavioural plasticity because it decreases the costs and increases the benefits of alternative behaviours. Moreover, because trade-offs change with age and plasticity is related to trade-offs, plasticity should also change with age. While the ability of animals to adjust to current trade-offs is fundamental for behavioural ecology, demonstration of ranges, slopes, and shapes of plastic behavioural responses is virtually absent from the literature. Knowledge concerning the ability of animals to adjust to environmental fluctuations is important for making predictions about population viability, but empirical evidence is greatly needed to validate current generalizations.
Foraging behaviour of American oystercatchers in response to declining prey densities
Authors: Tuckwell Joanne , Nol Erica
Published: March 2008

American oystercatchers (Haematopus palliatus) responded to declines in the density of oysters (Crassostrea virginica) on a commercial oyster bed examined in 1979 and 1995 by increasing the number of species of prey eaten and search times, but not peck rates or handling times. Seasonal changes in foraging behaviour included oystercatchers choosing larger oysters with longer handling times in winter than in autumn, but with subsequently greater profitability and higher intake rates. Time budgets of foraging birds were similar in the two seasons. Oystercatchers ate fewer mussels in winter than in autumn, and fewer mussels than oysters at all times. Search and handling times for mussels were similar in autumn of the 2 years. After a commercial harvest of oysters at a second site, handling times for oysters did not decline; however, search times were significantly more variable, niche breadth was greater, and there was a trend towards longer search times post harvest. The recorded changes in foraging behaviour indicated a close match between search and handling times and prey density and size and behavioural flexibility of foraging birds in response to sometimes drastic changes in their prey base.
Treatment of experimental alveolar echinococcosis with albendazole: a 1H NMR spectroscopic study
Authors: Modha A. , Novak M. , Blackburn B. J.
Published: March 2008

The Meriones unguiculatus (jird) – Echinococcus multilocularis host–parasite model was used to evaluate metabolic changes in livers and cysts treated with albendazole (ABZ). Hydrogen-1 nuclear magnetic resonance spectra of liver extracts showed that livers of uninfected jirds fed olive oil contained more glycine but less glycerophosphocholine (GPC) than those of uninfected untreated controls. When ABZ was added to the olive oil and tested on uninfected animals, other modifications in the metabolic profile of the liver could be seen. While the concentration of GPC stayed reduced and that of glycine reverted to normal, the levels of glycogen, phosphocreatine/creatine (PCr/Cr), succinate, and acetate were lower than those in the normal liver. The metabolic pathology in this organ was further magnified in jirds infected with E. multilocularis. In this case, the liver was depleted of glycogen, glucose, taurine, GPC, and acetate, but had more betaine, phosphocholine, choline, PCr/Cr, and succinate. These abnormalities were markedly diminished by ABZ treatment, with only glycogen, GPC, and acetate concentrations being low when the treatment was terminated. Also, the drug suppressed the growth of the parasite by 75%, and extracts of these parasite cysts contained less glycogen, glycine, succinate, acetate, and alanine but more taurine, GPC, and PCr/Cr than extracts of those from untreated hosts.
Holocene fossil beetles from a treeline peatland in subarctic Quebec
Authors: Lavoie C. , Elias S. A. , Payette S.
Published: March 2008

We analyzed the fossil insect fauna of a palsa peatland located 10 km south and east of the treeline in subarctic Quebec (57°45′N, 76°15′W) to detect any changes in the species composition during the Holocene epoch and to infer past environmental conditions in the study area. A minimum of 802 beetle individuals were recovered from a 2-m peat section, representing 51 taxa (18 identified to the species level) and 8 families. Trechus crassiscapus, Eucnecosum brunnescens, and Olophrum rotundicolle were the most common species found in the peat. The insect assemblage was quite stable through the study interval (5850–1950 BP). The formation of the palsa (where the peat section was excavated) occurred probably after 1950 BP, raising the soil surface above water level and preventing additional peat accumulation. The proportion of boreal forest species in the faunal assemblage is high (88%). The only arctic (tundra) species found were Amara alpina and Pterostichus arcticola. Many species were out of their modern distribution range, but since collection localities are scarce in subarctic Quebec, the modern range of these species may extend to the study site. A mutual climatic range analysis, employing beetles identified to the species level, showed that the mean July temperature of the study area between 5850 and 1950 BP was possibly 2.8–5.5 °C higher than during the 20th century. This assertion is supported by other paleoecological data (pollen and charcoal remains) suggesting a cooling trend in the study area after 2000 BP. However, since the last 2000 years are missing from the sampled peat section, it was not possible to quantify the impact of the cooling trend on the beetle fauna.
Male–female morph interactions in the damselflyNehalennia irene(Hagen)
Authors: Forbes Mark R. , Schalk Gina , Miller J. Greg , Richardson Jean M. L.
Published: March 2008

Several hypotheses concerning factors that favour coexistence of female morphs in damselflies (Zygoptera: Odonata) invoke differential attraction to (or harassment of) female morphs from mate-searching males. We designed experiments to determine whether males were differentially attracted to either of two discrete female morphs in a damselfly, Nehalennia irene (Hagen). One female morph was similar in colour and pattern to the conspecific male ("androchrome") and the other was dissimilar ("gynochrome"). Males were indiscriminate in their mating attempts. Overall, males were more attracted to gynochrome females; however, males that showed high response intensity to model males were equally likely to grasp models of the gynochrome and androchrome females. During male–female encounters in the field, androchrome females were more likely to chase males, whereas gynochrome females showed more refusal displays. Other direct and indirect evidence suggests that gynochrome females may be greater targets of sexual aggression than androchrome females while at the pond's edge, but that androchrome females more often frequent the pond's edge. Whether or not these differences in behaviour translate into differential costs and benefits of being a particular morph is unknown.
Ultrastructural characteristics of spermatogenesis in three species of deep-sea hydrothermal vent mytilids
Authors: Pennec Marcel Le , Beninger Peter G.
Published: March 2008

To enhance our understanding of the reproductive biology of deep-sea hydrothermal vent mytilids, the histology of the male gonad and the ultrastructure of its gametes were studied in Bathymodiolus thermophilus, B. puteoserpentis, and B. elongatus. Specimens of B. thermophilus were collected at the 13°N site on the East Pacific ridge, while B. puteoserpentis were sampled from the Snake Pit site of the mid-Atlantic ridge and B. elongatus were obtained from the North Fiji Basin. Gonad histology conformed to the typical bivalve profile; the differences in the proportions of acinal and interacinal tissue, as well as differences in acinal fullness in B. puteoserpentis, indicate that gametogenesis is discontinuous in these deep-sea mytilids. Evidence of protandric hermaphroditism was observed in B. elongatus, which exhibited acini containing both maturing and residual male gametes and immature oocytes. The ultrastructural characteristics of the male gametes conform to those described for littoral bivalve species, and the spermatozoon is of the primitive type. No species-specific differences in spermatozoon ultrastructure were discerned. No evidence of bacterial inclusions was found in either the gametes or the associated gonad cells in any of the species examined. The male gametes are thus probably not vectors for the endosymbiotic bacteria that characterize the nutritional biology of the adults in this genus.
Cold acclimation increases activities of mitochondrial long-chain acyl-CoA synthetase and carnitine acyl-CoA transferase I in heart of rainbow trout (Oncorhynchus mykiss)
Authors: Patey Christopher P. , Driedzic William R.
Published: March 2008

Rainbow trout (Oncorhynchus mykiss) were acclimated to 5 or 15 °C. Hearts were excised and assayed for the activity of enzymes essential for fatty acid metabolism. The activity of long-chain acyl-CoA synthetase, the first enzyme required in either fatty acid oxidation or complex fatty acid synthesis, was increased following acclimation to low temperature. Total crude homogenates exhibited an increase in activity with either palmitate (0.037–0.047 μmol/(min∙g)), stearate (0.037–0.055 μmol/(min∙g)), or oleate (0.041–0.064 μmol/(min∙g)) as substrate. Mitochondrial preparations showed the greatest increase in activity with palmitate (0.486–0.962 nmol/(min∙g)) as substrate, whereas microsomal preparations exhibited the greatest increase in activity with oleate (0.976–1.933 nmol/(min∙g)) as substrate. The activity of carnitine acyl-CoA transferase I, which is located on the outer mitochondrial membrane and is required for fatty acid oxidation, increased following acclimation to low temperature with palmitoyl CoA (0.137–0.352 μmol/(min∙g)), stearoyl CoA (0.066–0.152 μmol/(min∙g)), or oleoyl CoA (0.137–0.224 μmol/(min∙g)) as substrate. The parallel increase in mitochondrial long-chain acyl-CoA synthetase and carnitine acyl-CoA transferase I is consistent with previous observations of an elevated capacity of heart to oxidize fatty acids as exogenous fuels following acclimation to low temperature. The increase in microsome-based long-chain acyl-CoA synthetase may contribute to heart growth at low temperature.
COVARIANT HAMILTONIAN FIELD THEORY
Authors: STRUCKMEIER JÜRGEN , REDELBACH ANDREAS
Published: March 2008

A consistent, local coordinate formulation of covariant Hamiltonian field theory is presented. Whereas the covariant canonical field equations are equivalent to the Euler–Lagrange field equations, the covariant canonical transformation theory offers more general means for defining mappings that preserve the form of the field equations than the usual Lagrangian description. It is proven that Poisson brackets, Lagrange brackets, and canonical 2-forms exist that are invariant under canonical transformations of the fields. The technique to derive transformation rules for the fields from generating functions is demonstrated by means of various examples. In particular, it is shown that the infinitesimal canonical transformation furnishes the most general form of Noether's theorem. Furthermore, we specify the generating function of an infinitesimal space-time step that conforms to the field equations.
ROLE OF MIGRATORY BIRDS UNDER ENVIRONMENTAL FLUCTUATION — A MATHEMATICAL STUDY
Authors: CHATTERJEE SAMRAT , PAL S. , CHATTOPADHYAY J.
Published: March 2008

Chatterjee and Chattopadhyay1proposed and analyzed a simple one season eco-epidemiological model to understand the role of migratory birds in an eco-epidemiological scenario. In this paper, we have modified their model taking into account standard incidence as horizontal incidence. We have studied the proposed model both in the absence and in the presence of environmental disturbances. From our analysis, we observe that in the absence of the environmental fluctuations, the disease spread by migratory birds may be controlled by either decreasing the contact rate, or increasing the recovery or predation rates. Further, we also observe that if the artificial eutrophication (or intensity of white noise) is kept under a certain threshold value, the control procedure proposed in the deterministic case is also valid in the presence of environmental disturbances.
FEW WALLED CARBON NANOTUBE PRODUCTION IN LARGE-SCALE BY NANO-AGGLOMERATE FLUIDIZED-BED PROCESS
Authors: ZHANG QIANG , YU HAO , LIU YI , QIAN WEIZHONG , WANG YAO , LUO GUOHUA , WEI FEI
Published: March 2008

Few walled carbon nanotubes (FWCNTs) have been successfully synthesized using a nano-agglomerate fluidized-bed process. FWCNTs can be obtained by fluidization of Fe ( Co / Ni )/ Mo / MgO catalysts at a high temperature with methane cracking in a nano-agglomerate fluidized-bed reactor. The products were mainly 2 to 5 walled CNTs with an outer diameter of 1–7 nm in high purity, as revealed by Raman spectrometry, SEM, and HRTEM analysis. Two keys were crucial for this process. The first key was to get the small size of activity catalyst particles which was realized by Mo addition in catalyst. The graphitization of FWCNTs strongly depended on the composition of catalyst. Fe / Mo / MgO catalyst showed the highest activity and the FWCNT product with the best graphitization. Another key for this process was that the particles must be kept in fluidized state during FWCNT formation. Detailed process information was reported in this article, which showed a potential way for the large scale production of FWCNTs, thereby the urgent need for FWCNTs in high performance will be overcome.