bluuebunny/crossref_metadata_2025 huggingface dataset:
Ritualized fighting and biological armor: the impact mechanics of the mantis shrimp's telson
Authors: Taylor J. R. A. , Patek S. N.
Published: October 2010

Resisting impact and avoiding injury are central to survival in situations ranging from the abiotic forces of crashing waves to biotic collisions with aggressive conspecifics. Although impacts and collisions in biology are ubiquitous, most studies focus on the material properties of biological structures under static loading. Here, we examine the mechanical impact properties of the mantis shrimp's telson, a piece of abdominal armor that withstands repeated, intense impacts from the potent hammer-like appendages used by conspecifics during ritualized fighting. We measured the coefficient of restitution, an index of elasticity, of the telson and compared it with that of an adjacent abdominal segment that is not impacted. We found that the telson behaves more like an inelastic punching bag than an elastic trampoline, dissipating 69% of the impact energy. Furthermore, although the abdominal segment provides no mechanical correlates with size, the telson's coefficient of restitution, displacement and impact duration all correlate with body size. The telson's mineralization patterns were determined through micro-CT (Computed Tomography) and correspond to the mechanical behavior of the telson during impact. The mineralized central region of the telson ‘punched’ inward during an impact whereas the surrounding areas provided elasticity owing to their reduced mineralization. Thus, the telson effectively dissipates impact energy while potentially providing the size-related information crucial to its role in conspecific assessment. This study reveals the mechanical infrastructure of impact resistance in biological armor and opens a new window to the biomechanical underpinnings of animal behavior and assessment.
Biosilicification of loricate choanoflagellate: organic composition of the nanotubular siliceous costal strips of Stephanoeca diplocostata
Authors: Gong Ningping , Wiens Matthias , Schröder Heinz C. , Mugnaioli Enrico , Kolb Ute , Müller Werner E. G.
Published: October 2010

Loricate choanoflagellates (unicellular, eukaryotic flagellates; phylum Choanozoa) synthesize a basket-like siliceous lorica reinforced by costal strips (diameter of approximately 100 nm and length of 3 μm). In the present study, the composition of these siliceous costal strips is described, using Stephanoeca diplocostata as a model. Analyses by energy-dispersive X-ray spectroscopy (EDX), coupled with transmission electron microscopy (TEM), indicate that the costal strips comprise inorganic and organic components. The organic, proteinaceous scaffold contained one major polypeptide of mass 14 kDa that reacted with wheat germ agglutinin. Polyclonal antibodies were raised that allowed mapping of the proteinaceous scaffold, the (glyco)proteins, within the costal strips. Subsequent in vitro studies revealed that the organic scaffold of the costal strips stimulates polycondensation of ortho-silicic acid in a concentration- and pH-dependent way. Taken together, the data gathered indicate that the siliceous costal strips are formed around a proteinaceous scaffold that supports and maintains biosilicification. A scheme is given that outlines that the organic template guides both the axial and the lateral growth of the strips.
DDX6 recruits translational silenced human reticulocyte 15-lipoxygenase mRNA to RNP granules
Authors: Naarmann Isabel S. , Harnisch Christiane , Müller-Newen Gerhard , Urlaub Henning , Ostareck-Lederer Antje , Ostareck Dirk H.
Published: October 2010

Erythroid precursor cells lose the capacity for mRNA synthesis due to exclusion of the nucleus during maturation. Therefore, the stability and translation of mRNAs that code for specific proteins, which function in late stages of maturation when reticulocytes become erythrocytes, are controlled tightly. Reticulocyte 15-lipoxygenase (r15-LOX) initiates the breakdown of mitochondria in mature reticulocytes. Through the temporal restriction of mRNA translation, the synthesis of r15-LOX is prevented in premature cells. The enzyme is synthesized only in mature reticulocytes, although r15-LOX mRNA is already present in erythroid precursor cells. Translation of r15-LOX mRNA is inhibited by hnRNP K and hnRNP E1, which bind to the differentiation control element (DICE) in its 3′ untranslated region (3′UTR). The hnRNP K/E1-DICE complex interferes with the joining of the 60S ribosomal subunit to the 40S subunit at the AUG. We took advantage of the inducible human erythroid K562 cell system that fully recapitulates this process to identify so far unknown factors, which are critical for DICE-dependent translational regulation. Applying RNA chromatography with the DICE as bait combined with hnRNP K immunoprecipitation, we specifically purified the DEAD-box RNA helicase 6 (DDX6) that interacts with hnRNP K and hnRNP E1 in a DICE-dependent manner. Employing RNA interference and fluorescence in situ hybridization, we show that DDX6 colocalizes with endogenous human (h)r15-LOX mRNA to P-body–like RNP granules, from which 60S ribosomal subunits are excluded. Our data suggest that in premature erythroid cells translational silencing of hr15-LOX mRNA is maintained by DDX6 mediated storage in these RNP granules.
What Influences How Higher-Status People Respond to Lower-Status Others? Effects of Procedural Fairness, Outcome Favorability, and Concerns About Status
Authors: Blader Steven L. , Chen Ya-Ru
Published: October 2010

How do individuals with higher status react to their encounters with lower-status counterparts? Four studies explore this issue, focusing on higher-status parties' concerns with the outcome favorability and procedural fairness of those encounters. Across a wide range of contexts and bases of status, Study 1 found an interaction effect in which outcome favorability had a stronger relationship with higher-status parties' reactions when procedural fairness was high rather than low, in sharp contrast to previous findings in the justice literature. Studies 2, 3, and 4 explored the mechanism underlying this novel finding, testing the proposal that this interaction pattern is rooted in higher-status individuals' use of outcome and procedure information to determine whether their counterpart is validating—or challenging—their relatively higher status position. They conduct this test by examining the moderating influence of dispositional factors that vary the extent to which individuals are interested in social information from their lower-status counterpart regarding their relative status position. In particular, they test the prediction that the interaction will be accentuated among individuals who are (1) low in self-esteem, (2) high in need to belong, (3) low in power distance orientation, and (4) high in general concern about status. Results confirm these predictions. Theoretical and practical implications of these findings for social exchanges at work, organizational justice, and status are discussed.
E-mail as a Source and Symbol of Stress
Authors: Barley Stephen R. , Meyerson Debra E. , Grodal Stine
Published: October 2010

The increasing volume of e-mail and other technologically enabled communications are widely regarded as a growing source of stress in people's lives. Yet research also suggests that new media afford people additional flexibility and control by enabling them to communicate from anywhere at any time. Using a combination of quantitative and qualitative data, this paper builds theory that unravels this apparent contradiction. As the literature would predict, we found that the more time people spent handling e-mail, the greater was their sense of being overloaded, and the more e-mail they processed, the greater their perceived ability to cope. Contrary to assumptions of prior studies, we found no evidence that time spent working mediates e-mail-related overload. Instead, e-mail's material properties entwined with social norms and interpretations in a way that led informants to single out e-mail as a cultural symbol of the overload they experience in their lives. Moreover, by serving as a symbol, e-mail distracted people from recognizing other sources of overload in their work lives. Our study deepens our understanding of the impact of communication technologies on people's lives and helps untangle those technologies' seemingly contradictory influences.
The Enabling Role of Social Position in Diverging from the Institutional Status Quo: Evidence from the UK National Health Service
Authors: Battilana Julie
Published: October 2010

This study examines the relationship between social position, both within the field and within the organization, and the likelihood of individual actors initiating organizational changes that diverge from the institutional status quo. I explore this relationship using data from 93 change projects conducted by clinical managers at the National Health Service in the United Kingdom. The results show social position, both within the field and within the organization, influences actors' likelihood to initiate two types of organizational change that diverge from the institutional status quo, namely, (1) changes that diverge from the institutionalized template of role division among organizations and (2) changes that diverge from the institutionalized template of role division among professional groups in a field. The findings indicate that these two types of divergent organizational change are likely to be undertaken by individual actors with different profiles in terms of social position within the field and the organization.
Patients’ Knowledge of Risk Factors for Dental Disease. A Pilot Service Evaluation in a General Dental Practice
Authors: Aggarwal Vishal R , Javidi Hanieh , Joughin Amy , Crawford Fiona IJ , Sharif Mohammad O
Published: October 2010

The major dental diseases, including erosion, caries and periodontal disease, are preventable, and the Department of Health has produced guidelines in a ‘Prevention Toolkit’ to aid prevention of these diseases in primary care.

Aim

To investigate patients’ knowledge of the key themes in the Prevention Toolkit and to compare their knowledge of the different dental diseases.

Methods

Patients attending a general dental practice in North West England were asked to complete a questionnaire while they waited to see their dentist. The questionnaire had been piloted for readability, relevance of questions, and ease of use. It included nine true/false questions on key prevention messages. Data from the respondents were used to assess whether there were differences in knowledge by age or gender and between the types of dental diseases. Results were analysed using chi-square tests.

Results

105 patients completed the questionnaire. Of the 420 questions relating to periodontal diseases, 322 (77%) were answered correctly and 196 (47%) of the 420 questions on caries were answered correctly; however, only 32 (31%) of the 105 questions relating to erosion were answered correctly. There were significantly lower levels of knowledge of caries ( P<0.01) compared with periodontal diseases. Worryingly, 47 (45%) of 105 respondents stated incorrectly that brushing teeth immediately after consuming a ‘fizzy’ drink would protect the teeth.

Conclusion

The results of this pilot service evaluation indicate that in the practice concerned, more needs to be done to promote disease prevention at the primary care level. The current questionnaire could form a valuable tool to audit and reinforce patients’ knowledge, although it needs further development and validation. Longitudinal evaluation of the questionnaire, linking it with disease outcome measures, has the potential to indicate whether change in knowledge translates into behavioural change.
Testing the predictors of boredom at school: Development and validation of the precursors to boredom scales
Authors: Daschmann Elena C. , Goetz Thomas , Stupnisky Robert H.
Published: October 2010

Background. Boredom has been found to be an important emotion for students' learning processes and achievement outcomes; however, the precursors of this emotion remain largely unexplored.

Aim. In the current study, scales assessing the precursors to boredom in academic achievement settings were developed and tested.

Sample. Participants were 1,380 grade 5–10 students in mathematics classes.

Method. The Precursors to Boredom Scales were tested for structural and convergent validity with multi‐level confirmatory factor analyses (ML‐CFA), and differences in the perception of the precursors of boredom due to gender were investigated.

Results. The first ML‐CFA found support for the structural validity of the Precursors to Boredom Scales. In a second ML‐CFA, the newly developed boredom scales showed good convergent validity with several key aspects of instructional quality. Finally, the results supported previous research that found no gender differences in academic self‐concept and interest.

Conclusion. The precursors contained in our scales are empirically separable. Implications of the current findings for research on boredom among students are discussed.
Brand Attachment and Brand Attitude Strength: Conceptual and Empirical Differentiation of Two Critical Brand Equity Drivers
Authors: Park C. Whan , Macinnis Deborah J. , Priester Joseph , Eisingerich Andreas B. , Iacobucci Dawn
Published: October 2010

Research has not verified the theoretical or practical value of the brand attachment construct in relation to alternative constructs, particularly brand attitude strength. The authors make conceptual, measurement, and managerial contributions to this research issue. Conceptually, they define brand attachment, articulate its defining properties, and differentiate it from brand attitude strength. From a measurement perspective, they develop and validate a parsimonious measure of brand attachment, test the assumptions that underlie it, and demonstrate that it indicates the concept of attachment. They also demonstrate the convergent and discriminant validity of this measure in relation to brand attitude strength. Managerially, they demonstrate that brand attachment offers value over brand attitude strength in predicting (1) consumers’ intentions to perform difficult behaviors (those they regard as using consumer resources), (2) actual purchase behaviors, (3) brand purchase share (the share of a brand among directly competing brands), and (4) need share (the extent to which consumers rely on a brand to address relevant needs, including those brands in substitutable product categories).
How Complementarity and Substitution Alter the Customer Satisfaction–Repurchase Link
Authors: Voss Glenn B. , Godfrey Andrea , Seiders Kathleen
Published: October 2010

Customer satisfaction is universally acknowledged as a key driver of customer repurchase behavior, but recent evidence suggests that satisfaction has no effect on repurchase under certain circumstances. In this study, the authors develop a framework for understanding the complex relationships among satisfaction, moderating variables, and repurchase. They propose that the satisfaction–repurchase link is subject to complementary and substitute effects and present satiation and inertia as key theoretical mechanisms that explain and predict those effects. In weak-satiation purchase categories, complementary effects are more likely, which suggests that managers should invest in customer satisfaction and complementary initiatives simultaneously. In strong-satiation purchase categories, substitute effects are more likely, which suggests that managers should invest in either customer satisfaction or substitute initiatives. An empirical test combining survey and longitudinal purchase data from two categories—fashion apparel and automobile service—provides a remarkable degree of support for the propositions. The findings offer new theoretical insights and substantive guidance for managers to effectively allocate resources to initiatives that complement or substitute for customer satisfaction.
International Perspectives
Authors: Gadzinowski J. , Mazela J. , Papiernik E. , Draper E.S. , Kollée L.A.A , Agostino R. , Zeitlin J. ,   on behalf of MOSAIC Group
Published: October 2010

Regionalized level III perinatal care was implemented in Poland in 1998, but no comparative analyses of neonatal mortality and morbidity between other European regions and Poland are yet available. Given the large differences in policy and organization of health care between European countries, studying clinical outcomes within this context provides an opportunity to explore the effectiveness of regionalized care. The aim of this analysis was to compare the specific position of neonatal care in Poland with that of other European regions participating in the Models of OrganiSing Access to Intensive Care for very preterm babies (MOSAIC) project. In 1988, there were 18,798 live births in the 11 neonatal units in the Wielkopolska region; in 2003, there were 42,619 live births in the MOSAIC program from 53 neonatal units in the Wielkopolska and Lubuskie regions. There was no change in the rate of very preterm live births between 1988 and 2003, but the mortality rate among infants between 27 and 31 weeks of gestation differed significantly. The in-hospital mortality rate in the two Polish regions was higher in 2003 compared with other MOSAIC participants (35.3%and 17.3%, respectively). There was also a higher rate of congenital malformations, intraventricular hemorrhage, and periventricular leukomalacia. There were also clear differences in organization of perinatal care, with fewer level III centers per 10,000 deliveries in Polish regions compared with other European regions (0.25 and 1.33, respectively) and longer distances of neonatal transport (97 km and 29 km, respectively).
Cytomegalovirus infection after kidney transplantation, susceptibility to CMV-infection in association with HLA-genotype — Doctoral dissertation summary
Authors: Varga Marina
Published: October 2010

Cytomegalovirus infection is a major infectious complication of transplant recipients, causing significant morbidity and mortality. It is possible to treat this infection effectively only if we know the direct and indirect effects of it, if we take the risk-factors into account, and use sensitive and reliable diagnostic methods for early establishment of diagnosis. In order to avoid severe CMV-infection, it is possible to administer prophylactic therapy. For prophylaxis planning it is important to know the CMV-seroprevalence of Hungarian population and its characteristics. Our results have shown that the seroprevalence of Hungarian population is high: 86%. The primary CMV-infection in Hungary occurs in childhood or in early adulthood, till age of 20 years the seroprevalence is 72%. CMV-seronegative recipients should be transplanted using organs of seronegative donors, however, the chance obtaining the graft from a CMV-seronegative donor was shown to be 2% only. Since such seromatching is rear, we have to know that the constellation of negative recipient and positive donor is the highest risk-factor for developing severe primary CMV-infection. While investigating data of 147 CMV-seronegative recipients from high-risk group it has been established that CMV-infection prophylaxis is essential for high risk patients in the early post-transplant period of 3 months, the administration of any of investigated prophylactic protocols is advantageous in comparing with prophylaxis free management of those patients (P=0.006). The study has also proven that monoprophylaxis with ganciclovir or valganciclovir is the most effective and cost-effective procedure as compared to other protocols (P=0.006). It is important to take into consideration that in prophylactic groups the “late-onset” CMV-infection occurred often (25.4%), and that there were no signs of seroconversion after the primary CMV-infection in 14% of the patients. For the first time it has been found and proven that the female sex is a risk factor for CMV-infection (P=0.0006). Genetic variability influences susceptibility to infectious diseases and HLA-molecules are critical for viral antigen uptaking, processing and presenting. Our data of 129 of high-risk patients suggest that recipients positive for HLA-DQ3 are more susceptible to CMV-infection than a comparable group of patients negative for this HLA-type. This result was not due to rejection and/or treatment for rejection and was not influenced by induction therapy or number of HLA-mismatches. The multivariate Cox Regression analysis has shown that HLA-DQ3 positivity is an independent predictor of primary CMV-infection in CMV-seronegative recipients with seropositive donor grafts (P=0.001). The cognition of HLA-DQ3 is useful in the prediction of acute CMV-infection in high-risk patients, and should influence the planning of the patients' management.
Preconditioning is a method that may reduce the negative side-effect of pneumoperitoneum
Authors: Jávor Szaniszló Z. , Shanava K. , Hocsák E. , Kürthy M. , Lantos J. , Borsiczky B. , Takács I. , Horváth Sz. , Balatonyi B. , Ferencz S. , Ferencz A. , Rőth E. , Wéber Gy.
Published: October 2010

Increased intra-abdominal pressure during laparoscopy leads to hypoxia due to reduced blood flow. Aim of our study was to investigate whether preconditioning can reduce this negative effect of the pneumoperitoneum. Fifty female Wistar rats were used, divided into 5 groups. I: Sham operation (Sham), II: conventional pneumoperitoneum (PP), III: transvaginal pneumoperitoneum (TV), IV: preconditioning for 2.5 minutes in two cycles (Pre 2.5), V: preconditioning for 5 minutes (Pre 5). Malondialdehyde (MDA), reduced glutathione (GSH), sulfhydrylgroup (SH-) concentrations, superoxide-dismutase (SOD) and mieloperoxidase (MPO) activity, and anti-apoptotic pathway marker p-AKT level and inflammatory cytokine TNF-α were measured. SOD activity and GSH concentration were decreased in PP and TV groups comparing to Sham and preconditioning groups. MPO activity was decreased also in PP and TV groups comparing to the Sham group but in the preconditioning groups it has remained high. MDA concentration in plasma was increased in PP and TV groups comparing to Sham and preconditioning groups. There was no difference in the case of blood MDA and SH-concentrations between groups. Anti-apoptotic pathway marker p-AKT level was decreased in the TV group comparing to the sham and preconditioning groups. TNF-α level was increased in TV and preconditioning groups compared to the sham group. According to the results preconditioning can reduce negative effects of pneumoperitoneum.
Successful urinary tract reconstruction following ureteral necrosis in kidney transplant patient
Authors: Piros László , Deák P. Á. , Dallos G. , Máthé Zs. , Doros A.
Published: October 2010

Ureteric complications following renal transplantation are well known to cause significant morbidity and compromised graft survival. The necrosis of a major part of the ureter could be a highly detrimental situation, and hardly solvable complication, that poses great challenges. Herein we are presenting a case report to introduce a possible surgical solution following repeated ineffective radiological interventions, in a patient with ureteric necrosis that appeared 3 months after cadaveric kidney transplantation. We transplanted the right kidney to the right iliac fossa performing end-to-side vascular anastomoses and end-to-side uretero-ureterostomy. His clinical course was uneventful during 3 months, when he presented a mild borderline acute cellular rejection together with dilatation of the pyelon. Percutaneous nephrostomy was performed by interventional radiologist. During further radiologic interventions the stenosis was not permeable. We finally made up our minds for surgical solution. We found a totally necrotized graftureter. During a second operation we performed a right nephrectomy, transsecting the pyelon. After mobilization of the transplanted kidney approaching and identifying the pyelon, a large pyelopyelar anastomosis was performed with stenting. The postoperative follow-up showed excellent urine flow from the kidney to the bladder, then the TRD was removed. Surgery had to be considered only if minimally invasive procedures are infeasible or ineffective. A regimen of reconstructive methods are well-known, but all cases have to be evaluated individually. If the native kidneys can be removed, their pyelons and entire ureters should be used for reconstruction.
Spatial and Temporal Variability in Atka Mackerel Female Maturity at Length and Age
Authors: Cooper Daniel W. , McDermott Susanne F. , Ianelli James N.
Published: October 2010

Spatial and temporal variability in maturity at length and maturity at age was examined for female Atka mackerel Pleurogrammus monopterygius in the eastern and central Aleutian Islands of Alaska. Postovulatory follicles (POFs) were evaluated as a potential character to distinguish spent mature fish from immature fish. We estimated that POFs remain in the ovaries for approximately 1 month after spawning, therefore allowing us to include some collections of recently spent fish for maturity estimates. Maturity-at-length data varied significantly among geographic areas and years, whereas maturity-at-age data failed to indicate differences. These results are probably attributable to different growth rates between the areas. An age-based model was developed to account for differences in year-class strengths, and modeling results showed that length at maturity could vary by as much as 4 cm over time because of variable recruitment. Maturity in Atka mackerel seems to be determined more by age than by somatic body size.
Characterisation of permeability to gas of geosynthetic clay liners in unsaturated conditions
Authors: Mendes M.J.A. , Pierson P. , Touze-Foltz N. , Mora H. , Palmeira E.M.
Published: October 2010

ABSTRACT: This paper is a contribution to the characterisation of permeability to gas of unsaturated GCLs, with applications in cover liners of municipal solid waste landfills. Conducting such tests at low gas pressure gradient limits the risk of moisture distribution change in the bentonite, which has been observed under high pressure gradients. However, a consequence of a low pressure gradient is a small gas flow rate that is difficult to measure with good accuracy. Therefore a solution may be the use of transient state tests, such as the falling pressure test adapted to GCL permeability characterisation. This paper shows the influence of the main parameters related to the test, and to the material tested (natural or activated calcium bentonite, moisture content, presence or not of small cracks in the bentonite). The results obtained showed good repeatability for gas differential pressures up to 40 kPa for the test conditions employed in this work. The results showed that the gravimetric moisture content of the GCL necessary to attain a certain permeability value depends on the nature of the bentonite, which was not observed in terms of volumetric moisture content. However, other factors were shown to be more important than the nature of bentonite in GCL permeability to gas: the desiccation due to the gas flow can significantly increase the permeability, which compromises the GCL's performance as a gas barrier.
Climate and predation dominate juvenile and adult recruitment in a turtle with temperature‐dependent sex determination
Authors: Schwanz Lisa E. , Spencer Ricky-John , Bowden Rachel M. , Janzen Fredric J.
Published: October 2010

Conditions experienced early in life can influence phenotypes in ecologically important ways, as exemplified by organisms with environmental sex determination. For organisms with temperature‐dependent sex determination (TSD), variation in nest temperatures induces phenotypic variation that could impact population growth rates. In environments that vary over space and time, how does this variation influence key demographic parameters (cohort sex ratio and hatchling recruitment) in early life stages of populations exhibiting TSD? We leverage a 17‐year data set on a population of painted turtles, Chrysemys picta, to investigate how spatial variation in nest vegetation cover and temporal variation in climate influence early life‐history demography. We found that spatial variation in nest cover strongly influenced nest temperature and sex ratio, but was not correlated with clutch size, nest predation, total nest failure, or hatching success. Temporal variation in climate influenced percentage of total nest failure and cohort sex ratio, but not depredation rate, mean clutch size, or mean hatching success. Total hatchling recruitment in a year was influenced primarily by temporal variation in climate‐independent factors, number of nests constructed, and depredation rate. Recruitment of female hatchlings was determined by stochastic variation in nest depredation and annual climate and also by the total nest production. Overall population demography depends more strongly on annual variation in climate and predation than it does on the intricacies of nest‐specific biology. Finally, we demonstrate that recruitment of female hatchlings translates into recruitment of breeding females into the population, thus linking climate (and other) effects on early life stages to adult demographics.
DELAY DISCOUNTING OF QUALITATIVELY DIFFERENT REINFORCERS IN RATS
Authors: Calvert Amanda L. , Green Leonard , Myerson Joel
Published: October 2010

Humans discount larger delayed rewards less steeply than smaller rewards, whereas no such magnitude effect has been observed in rats (and pigeons). It remains possible that rats' discounting is sensitive to differences in the quality of the delayed reinforcer even though it is not sensitive to amount. To evaluate this possibility, Experiment 1 examined discounting of qualitatively different food reinforcers: highly preferred versus nonpreferred food pellets. Similarly, Experiment 2 examined discounting of highly preferred versus nonpreferred liquid reinforcers. In both experiments, an adjusting‐amount procedure was used to determine the amount of immediate reinforcer that was judged to be of equal subjective value to the delayed reinforcer. The amount and quality of the delayed reinforcer were varied across conditions. Discounting was well described by a hyperbolic function, but no systematic effects of the quantity or the quality of the delayed reinforcer were observed.
THE IDENTITIES HIDDEN IN THE MATCHING LAWS, AND THEIR USES
Authors: Thorne David R.
Published: October 2010

Various theoretical equations have been proposed to predict response rate as a function of the rate of reinforcement. If both the rate and probability of reinforcement are considered, a simple identity, defining equation, or “law” holds. This identity places algebraic constraints on the allowable forms of our mathematical models and can help identify the referents for certain empirical or theoretical coefficients. This identity can be applied to both single and compound schedules of reinforcement, absolute and relative measures, and to local, global and overall rates and probabilities. The rate matching equations of Hernstein and Catania appear to have been approximations to, and to have been evolving toward, one form of this algebraic identity. Estimates of the bias and sensitivity terms in the generalized ratio and logarithmic matching models are here held to be averaging artifacts arising from fitting procedures applied to models that violate or conceal the underlying identities.
External Threats and Military Intervention: The United States and the Caribbean Basin
Authors: Gent Stephen E.
Published: October 2010

Domestic political instability provides an incentive for external military intervention by raising the opportunity costs of nonintervention. When deciding to intervene in response to instability within its sphere of influence, a regional hegemon considers the anticipated actions of other potential interveners. In particular, a hegemon has an incentive to intervene preemptively to forestall future interventions by rival powers. Given this, military intervention will be more likely when another power provides an external threat to a hegemon’s sphere of influence. A historical examination of U.S. intervention policy and behavior in the Caribbean Basin supports the theory.
South Asian Ethnicity as a Risk Factor for Major Adverse Cardiovascular Events after Renal Transplantation
Authors: Prasad G. V. Ramesh , Vangala Sai K. , Silver Samuel A. , Wong Steven C.W. , Huang Michael , Rapi Lindita , Nash Michelle M. , Zaltzman Jeffrey S.
Published: October 2010

Background and objectives

South Asians (SAs) comprise 25% of all Canadian visible minorities. SAs constitute a group at high risk for cardiovascular disease in the general population, but the risk in SA kidney transplant recipients has never been studied.

Design, setting, participants, & measurements

In a cohort study of 864 kidney recipients transplanted from 1998 to 2007 and followed to June 2009, we identified risk factors including ethnicity associated with major cardiac events (MACEs, a composite of nonfatal myocardial infarction, coronary intervention, and cardiac death) within and beyond 3 months after transplant. Kaplan-Meier methodology and multivariate Cox regression analysis were used to determine risk factors for MACEs.

Results

There was no difference among SAs (n = 139), whites (n = 550), blacks (n = 65), or East Asians (n = 110) in baseline risk, including pre-existing cardiac disease. Post-transplant MACE rate in SAs was 4.4/100 patient-years compared with 1.31, 1.16, and 1.61/100 patient-years in whites, blacks, and East Asians, respectively (P < 0.0001 versus each). SA ethnicity independently predicted MACEs along with age, male gender, diabetes, systolic BP, and prior cardiac disease. SAs also experienced more MACEs within 3 months after transplant compared with whites (P < 0.0001), blacks (P = 0.04), and East Asians (P = 0.006). However, graft and patient survival was similar to other groups.

Conclusions

SA ethnicity is an independent risk factor for post-transplant cardiac events. Further study of this high-risk group is warranted.
Evidence-Based Review of the Utility of Radiation Therapy in the Treatment of Endometrial Cancer
Authors: Dewdney SB , Mutch DG
Published: October 2010

Endometrial cancer is the most common cancer of the female genital tract in the USA and usually presents at an early stage. Most women are cured with surgery, however, some patients may require adjuvant therapy including radiation and/or chemotherapy. Risk factors determine the need for adjuvant treatment and, based on these risk factors, patients are categorized as being at low, intermediate or high risk for recurrence. In this article we will review the best level of evidence available for the use of radiation therapy within each risk stratum. The most controversy and debate is associated with patients stratified to the intermediate-risk group.
Performance of Mammography in Women Aged under 40 Years
Authors: Voogd Adri C
Published: October 2010

Evaluation of: Yankaskas BC, Haneuse S, Kapp JM, Kerlikowske K, Geller B, Buist DSM; For the Breast Cancer Surveillance Consortium: Performance of first mammography examination in women younger than 40 years. J. Natl Cancer Inst. 102(10), 692–700 (2010). By using pooled data from six mammography registries across the USA, 117,737 women aged 18–39 years were identified who had received their first mammography in the period 1995–2005. A distinction was made between diagnostic mammography for women who presented with a breast problem (n = 30,956), and screening mammography (n = 86,781). The age-adjusted positive predictive value of screening mammography was 1.3% (95% CI: 1.1–1.5%), as compared with 14.6% (95% CI: 13.3–15.8%) for diagnostic mammography. Considering the high recall rates, the high number of false-positive test results and the low cancer detection rate, the appropriateness of mammography for women younger than 40 without symptoms is questionable.
Sex-Based Differences in Vascular Function
Authors: Miller VM
Published: October 2010

Cardiovascular disease is the leading cause of morbidity and mortality for both men and women in the USA. However, there are differences between the sexes in age-dependent onset, severity, symptoms and outcomes. Basic research into the causes of sex-dependent differences in cardiovascular disease is ongoing and includes investigation into genetic variation in expression and distribution of receptors for the sex steroids; specificity of natural and synthetic ligands that activate the sex steroid receptors; and intracellular mechanisms that are activated by the receptors in all components of the vessel wall and blood elements, which integrate to regulate vascular tone, vascular repair and remodeling in health and disease. In this era of personalized medicine, basic research into mechanisms of sex differences in vascular function will result in improved prevention, detection and treatment of cardiovascular disease in both men and women.
Flibanserin: A Potential Treatment for Hypoactive Sexual Desire Disorder in Premenopausal Women
Authors: Clayton AH , Dennerstein L , Pyke R , Sand M
Published: October 2010

Hypoactive Sexual Desire Disorder (HSDD) is defined as a persistent or recurrent deficiency of sexual fantasies and desire for sexual activity, which causes marked personal distress or interpersonal difficulty, and is not better accounted for by another psychiatric disorder or the direct physiological effects of a substance (e.g., a medication) or medical condition. HSDD is believed to be the most common form of Female Sexual Dysfunction and is associated with emotional distress and relationship problems. No pharmacologic therapy is approved for the treatment of HSDD in premenopausal or naturally postmenopausal women. Flibanserin is a 5-HT1A agonist/5-HT2A antagonist that is under investigation as a treatment for HSDD in women. The aim of this article is to present an overview of the pharmacology, clinical efficacy and safety of flibanserin. Flibanserin is an investigational drug that is not licensed for any indication in any country.
Celiac Disease: an Underappreciated Issue in Women's Health
Authors: Shah Sveta , Leffler Daniel
Published: October 2010

Celiac disease (CD) is an immune-mediated enteropathy that is secondary to gluten ingestion and classically associated with gastrointestinal symptoms. Diagnosis is based on serology and confirmatory duodenal biopsy, and the only treatment is lifelong avoidance of gluten. CD has been increasingly recognized to encompass a wide variety of manifestations that are relevant to women's health, including infertility, adverse pregnancy outcomes and reduced BMD. Currently, CD is underdiagnosed, largely owing to lack of recognition of the diverse manifestations by general practitioners. Increased awareness of the clinical spectrum of this disease, as well as targeted testing in at-risk individuals (including women with unexplained infertility and previous adverse pregnancy outcomes, and in specific populations with reduced BMD) is greatly needed in order to improve rates of diagnosis.
Regionwide Cumulative Effects Analysis of Long-Range Transportation Plans
Authors: Paulsen Chris , Crist Patrick J. , Kittel Gwen , Varley Ian
Published: October 2010

This study investigated the feasibility and limitations of a regionwide cumulative effects analysis of long-range transportation plans (LRTPs). The key to meaningful regional cumulative effects assessment and resource conservation planning is determining when a significant impact to any given resource has been reached. This study applied a select set of natural and cultural resource metrics to the 2035 long-range transportation plans of large, medium, and small metropolitan planning organizations (MPOs). A spatial analysis was conducted to calculate the cumulative loss in the distribution of four representative resources from the proposed transportation network and land use changes. The results generated information about the resource spatial distribution and retention requirements for long-term viability. The cumulative effects were measured against quantitative sustainability indicators of high, medium, and low risk; at that time, stakeholders and decision makers could make a determination of the significance of the environmental impacts before the LRTP was complete. Informed decisions can be made about trade-offs; changes can be made to plan alternatives to create more compatible plans, or mitigation of plan effects can be identified. The model used for this study is a flexible but robust model that does not impose an undue burden on a department of transportation or MPO, but it does rely on input from resource agency experts and other stakeholders. Data were readily available in a geographic information system format, and the process appears viable for most MPOs and partners.
Estimating Diesel Vehicle Emission Factors at Constant and High Speeds for Short Road Segments
Authors: Choi Hyung-Wook , Frey H. Christopher
Published: October 2010

Vehicle emission estimates with high spatial and temporal resolution are needed to estimate near-roadway air quality and human exposure to emissions. The U.S. Environmental Protection Agency's (EPA) MOBILE6 emission factor model is based on test cycles with transient speeds and durations on the order of 10 min. MOBILE6 does not report emission factors for average speeds higher than 65 mph. However, for near-roadway studies, emission factors are needed for short highway segments that represent only a few seconds of vehicle travel time at approximately constant speed and speeds greater than 65 mph. Constant-speed and high-speed correction factors for nitrogen oxides, hydrocarbons, carbon dioxide (CO2), and carbon monoxide were developed on the basis of 59,286 s of EPA dynamometer emissions data for diesel vehicles from which speed–acceleration modal models were derived. The constant speed correction factor is the ratio of the emission factor at constant speed to the emissions factor during transient cycles with an equivalent average speed. For example, the constant speed correction factor for CO2 increases from 0.71 to 1 as speed increases from 31 to 78 mph. High-speed correction factors are based on the ratio of emission factors at a constant speed greater than 65 mph to emission factors at a constant speed of 65 mph. For example, at 80 mph, the high-speed correction factor is approximately 1.5 for CO2. Sensitivity analysis of emission estimates to these correction factors was conducted for speeds of 40 to 80 mph.
Estimating In-Vehicle Concentration of and Exposure to Fine Particulate Matter
Authors: Liu Xiaozhen , Frey H. Christopher , Cao Ye
Published: October 2010

Fine particulate matter (PM2.5) exposure is associated with short-term and chronic respiratory effects. It is necessary to investigate human exposure to PM2.5 to support the assessment of the association between exposure and adverse health effects. The methodology used in the current version of Stochastic Exposure and Dose Simulation Model for Particulate Matter for in-vehicle PM2.5 concentration is reviewed. An alternative approach for estimating in-vehicle PM2.5 concentration, based on the use of a dispersion model to estimate near-road PM2.5 concentration and a mass balance model to estimate in-vehicle concentration, has been specified and applied. The objectives of this paper are to (a) demonstrate the application of the alternative approach to various scenarios, (b) analyze the sensitivity of the modeling results to the key inputs, and (c) evaluate this approach. Typical inputs for the alternative approach are reviewed. Sensitivities of these inputs to the modeling results and estimated human exposure have been analyzed. The in-vehicle PM2.5 concentration was estimated to vary by more than a factor of two, depending on factors such as the cabin air exchange rate and filter efficiency of the ventilation system. Recommendations are made for field data that would be useful to better characterize variability in factors that affect in-vehicle PM2.5 concentration.
Quantitative Assessment of Environmental and Economic Benefits of Recycled Materials in Highway Construction
Authors: Lee Jin Cheol , Edil Tuncer B. , Tinjum James M. , Benson Craig H.
Published: October 2010

The benefits of using recycled materials in highway pavements was assessed quantitatively by conducting life-cycle analysis and life-cycle cost analysis on pavements consisting of conventional and recycled materials for a highway construction project in Wisconsin. Results of the analysis indicate that using recycled materials in the base and subbase layers of a pavement can result in reductions in global warming potential (20%), energy consumption (16%), water consumption (11%), and hazardous waste generation (11%) while also extending the service life of the pavement. In addition, using recycled materials in the base and subbase layers can result in a life-cycle cost savings of 21%. The savings are even greater if landfill avoidance costs are considered for the recycled materials incorporated in the pavement. Extrapolation of the benefits to conditions nationwide indicates that modest changes in pavement design to incorporate recycled materials can contribute substantially to the emission reductions required to stabilize greenhouse gas emissions at current levels.
Total en bloc spondylectomy for lung cancer metastasis to the spine
Authors: Murakami Hideki , Kawahara Norio , Demura Satoru , Kato Satoshi , Yoshioka Katsuhito , Tomita Katsuro
Published: October 2010

Object

The prognosis in patients with a distant spinal metastasis from the lung is dismal. The role of radical surgery in such cases has been questioned because of the excessive morbidity, blood loss, and operative time as well as the tumor's extreme malignancy. The purpose of this study was to evaluate the surgical results and the prognosis associated with radical surgery for lung cancer metastasis to the spine in carefully selected patients and to clarify whether there is an indication for radical surgery such as total en bloc spondylectomy (TES) in lung cancer metastasis.

Methods

The author performed a retrospective review of patients with lung cancer spinal metastasis treated by TES during a 10-year period. Total en bloc spondylectomy for lung cancer metastasis to the spine was performed in 6 patients without visceral or other bony metastases. Outcome measures were prognostic score, mean survival time, and perioperative complications. The histological type was adenocarcinoma in all 6 cases. In 4 cases the surgical strategy prognostic score was 5. In the other 2 cases the score was 6 because there were skip metastases to adjacent vertebra. In the 2 cases with adjacent vertebral metastasis, the adjacent vertebra was excised en bloc together.

Results

The mean estimated blood loss was 1076 ml and the mean operative time was 7 hours 20 minutes. Perioperative complications were found in 2 cases. One was deep infection after CSF leakage, and the other was paralysis due to postoperative hematoma. At the end of follow-up period, 4 of 6 patients are still living after a mean of 46.3 months (range 36–62 months). In the other 2 cases, 1 patient died of a heart attack and the other of mediastinitis due to surgical site infection by methicillin-resistant Staphylococcus aureus. In this series, local recurrence was not found.

Conclusions

Total en bloc spondylectomy has been shown to be associated with excessive morbidity, blood loss, and operative time; however, the procedure is becoming less invasive. The authors conclude that TES is appropriate in selected cases with controllable primary lung cancer, localized spinal metastasis, and no visceral metastasis. In such patients, improvement in the prognosis can be expected after TES. However, even in selected cases and with skilled surgical technique, the complication rate remains high. Total en bloc spondylectomy should be performed after a thorough discussion of the risks and benefits.