bluuebunny/crossref_metadata_2025_split huggingface dataset:
Are ontogenetic shifts in diet linked to shifts in feeding mechanics?Scaling of the feeding apparatus in the banded watersnakeNerodia fasciata
Authors: Vincent Shawn E. , Moon Brad R. , Herrel Anthony , Kley Nathan J. 
Published: June 2007

SUMMARYThe effects of size on animal behaviour, ecology, and physiology are widespread. Theoretical models have been developed to predict how animal form,function, and performance should change with increasing size. Yet, numerous animals undergo dramatic shifts in ecology (e.g. habitat use, diet) that may directly influence the functioning and presumably the scaling of the musculoskeletal system. For example, previous studies have shown that banded watersnakes (Nerodia fasciata) switch from fish prey as juveniles to frog prey as adults, and that fish and frogs represent functionally distinct prey types to watersnakes. We therefore tested whether this ontogenetic shift in diet was coupled to changes in the scaling patterns of the cranial musculoskeletal system in an ontogenetic size series (70–600 mm snout–vent length) of banded watersnakes. We found that all cranial bones and gape size exhibited significant negative allometry, whereas the muscle physiological cross-sectional area (pCSAs) scaled either isometrically or with positive allometry against snout–vent length. By contrast, we found that gape size, most cranial bones, and muscle pCSAs exhibited highly significant positive allometry against head length. Furthermore, the mechanical advantage of the jaw-closing lever system remained constant over ontogeny. Overall, these cranial allometries should enable watersnakes to meet the functional requirements of switching from fusiform fish to bulky frog prey. However, recent studies have reported highly similar allometries in a wide diversity of vertebrate taxa, suggesting that positive allometry within the cranial musculoskeletal system may actually be a general characteristic of vertebrates.
Assessment of the pressure–volume relationship of the single ventricle of the grass shrimp, Palaemonetes pugio
Authors: Guadagnoli J. A. , Tobita K. , Reiber C. L. 
Published: June 2007

SUMMARY
The ventricular pressure–volume (PV) relationship has been used extensively to study the mechanics and energetics in multi-chambered hearts of closed circulatory system vertebrates. In the current study we applied the use of PV loops in the assessment of cardiac mechanics and energetics in the single ventricle of a decapod crustacean possessing an open circulatory system. Anatomical differences between multi-and single-chambered hearts include multiple ostia entering and valved multiple arterial systems exiting the ventricle, and the neurogenic origin of the heartbeat in decapod crustaceans. However, the microscopic architecture and excitation–contraction coupling events are similar in both systems. Ventricular pressure and area were obtained independently and integrated into pressure–area loops. Area was then converted to volume to generate PV loops. Based on the PV loops generated in this study, the ventricle of Palaemonetes pugio processes the same primary phases of the cardiac cycle as ventricles from the multi-chambered hearts of vertebrates: (1)isovolumic contraction, (2) ventricular emptying, (3) isovolumic relaxation and (4) ventricular filling. The area enclosed by the PV loop provides a measure of stroke work and when multiplied by heart rate provides an assessment of cardiac work. This initial examination of PV loops from a single-ventricle decapod crustacean demonstrates the utility of this technique to further elucidate the cardiac mechanics and energetics of this system, and in particular during times of physiological stress.
A male sex pheromone in a parasitic wasp and control of the behavioral response by the female's mating status
Authors: Ruther Joachim , Stahl Lina M. , Steiner Sven , Garbe Leif A. , Tolasch Till 
Published: June 2007

SUMMARY
Male insects may increase their chance of successful reproduction by releasing pheromones that attract females or elicit sexual acceptance. In parasitic wasps, male pheromones have been suggested for a few species but no chemicals have been identified so far. Here we report the first identification of a male sex pheromone in parasitic Hymenoptera. In abdomens of male jewel wasps, Nasonia vitripennis Walker, we found a mixture of(4R,5R)- and(4R,5S)-5-hydroxy-4-decanolide (HDL), which was released intermittently and attracted virgin females, but no males, in an olfactometer bioassay. However, only a few minutes after copulation mated females avoided the male-derived pheromone. Neither preference nor avoidance was shown by mated females after 24 h and even after they had been allowed to oviposit for 6 days. Nasonia vitripennis females normally mate only once. Thus,their variable response to the sex attractant depending on the mating status makes sense from an evolutionary perspective. Firstly, it increases the chance of virgins to be inseminated. Secondly, by terminating the response or even avoiding the male pheromone, mated females decrease the probability of encountering males and being disturbed by their courtship activities when searching for new oviposition sites.
Evaluation of mass flowrate through an axial gas turbine stage using different computational methods
Authors: Najjar Y. S. H. , Akeel S. A. M. S. 
Published: June 2007

Mass flowrate is very important, as it determines the frontal area, volume, size, and weight of the engine, and consequently, the momentum drag at certain flight conditions, specific fuel consumption, and the aircraft total loading. The mass flowrate is also needed to determine the shaft power and the thrust power developed by the engine when the specific work output is obtained. Different computational methods have been used in this research to find out their relative accuracy in determining the mass flow passing through an already designed, but not built, stage. The methods employed are free vortex variation of density using approximate scheme including mean radius, arithmetic average density, and numerical integration using the trapezoidal and Simpson's rule. Moreover, closed-form integration (theoretical) with free vortex, linear variation, and parabolic variation of density along the height of the blade was considered. The arithmetic average method was found to give the highest accuracy. The mean-radius method is the least accurate but the simplest. Hence, it is advised to be used especially in quick estimates. The difference in accuracy is not so great to justify using tedious and time-consuming methods.
The development of a model for in vitro testing of femoral stems in impaction bone grafting
Authors: Heal J S , Gozzard C , Gheduzzi S , Grimm B , Learmonth I D , Miles A W 
Published: June 2007

Comprehension of the biomechanical behaviour of orthopaedic implants is essential. This paper describes the development of an in vitro model to investigate the behaviour of femoral implants in the revision setting. The development of a femoral model and a bone graft substitute is described. The properties of human, bovine, ovine morselized bone graft, and a graft substitute were compared. On measuring hoop strain after impaction bone grafting there was no significant difference between the ovine bone graft and graft substitute with the size 1 Exeter stem. The results suggest that this bone graft substitute is a viable alternative for in vitro testing. The authors recommend the use of the graft substitute and the femoral model to predict femoral stem biomechanics.
Identification of Vertebral Fracture and Non-Osteoporotic Short Vertebral Height in Men: The MrOS Study
Authors: Ferrar Lynne , Jiang Guirong , Cawthon Peggy M , San Valentin Ria , Fullman Robin , Lambert Lori , Cummings Steven R , Black Dennis M , Orwoll Eric , Barrett-Connor Elizabeth , Ensrud Kris , Fink Howard A , Eastell Richard 
Published: June 2007

Abstract
Non-osteoporotic SVH may mimic VF but is excluded in ABQ. In men, this led to discordance between ABQ and other methods, but SVH was not linked to low bone density. Exclusion of SVH could reduce false positives.
Introduction: Non-osteoporotic short vertebral height (SVH) may mimic vertebral fracture (VF). The aims were to (1) compare the prevalence of VF in elderly men using the algorithm-based qualitative (ABQ), semiquantitative (SQ), and triage-quantitative morphometric (triage-QM) methods; (2) identify reasons for discordance between methods; and (3) determine whether SVH identified by ABQ is linked to low BMD.
Materials and Methods: We studied a subset of 732 men ages ≥65 yr participating in the Osteoporotic Fractures in Men (MrOS) Study. Criteria for VF were (1) ABQ: endplate depression; (2) SQ: estimated vertebral height reduction ≥20%; (3) triage-QM: vertebral height ratio &gt;3 SD below the reference mean, on radiographs showing evidence of VF. Criteria for SVH (ABQ) were apparent “reduction” in vertebral height ≥ ∼15%, without evidence of endplate depression.
Results: The prevalence of at least one VF was 10% (ABQ); 13% (SQ) and 11% (QM-triage) and of at least one SVH (ABQ) was &gt;50%. Agreement between methods was moderate (κ = 0.42–0.62). Discordance between methods related mainly to classification of mild thoracic wedging or possible traumatic VF by ABQ. Mean BMD was lower in men with VF (any diagnostic method) than in those without (two-sample t-test, p &lt; 0.05). For ABQ, BMD was similar in men with SVH (no VF) and men with normal vertebrae (ANOVA, p &gt; 0.05). Mean BMD was significantly lower than expected in 40 men with VF identified by all three methods and average or more than average in those identified by a single method.
Conclusions: Among elderly men (1) the prevalence of VF ranges from 10% to 13%: (2) agreement between diagnostic methods is moderate: discordance relates mainly to differential classification of mild thoracic deformities or ABQ definition of VF as traumatic; and (3) SVH identified by ABQ is common and not linked to low BMD.
Microcrack Frequency and Bone Remodeling in Postmenopausal Osteoporotic Women on Long-Term Bisphosphonates: A Bone Biopsy Study
Authors: Chapurlat Roland D , Arlot Monique , Burt-Pichat Brigitte , Chavassieux Pascale , Roux Jean Paul , Portero-Muzy Nathalie , Delmas Pierre D 
Published: June 2007

Abstract
We sought whether microdamage could rise in postmenopausal osteoporotic women on long-term bisphosphonates, as suggested by recent animal studies. We found few microcracks in iliac bone biopsies, despite a marked reduction in bone turnover.
Introduction: Animal studies suggest that bisphosphonates (BPs) could increase microdamage frequency in a dose-dependent manner, caused by excessively suppressed bone turnover. However, there is limited data in humans receiving BP therapeutic doses for &gt;3 yr.
Materials and Methods: We measured microcrack frequency and histomorphometry parameters on transiliac bone biopsies in 50 postmenopausal osteoporotic women (mean age = 68 yr) who had received BP therapy (3 on intravenous pamidronate, 37 on oral alendronate, and 10 on oral risedronate) for at least 3 yr (mean treatment duration = 6.5 yr). We compared these results with transiliac bone biopsies obtained from 12 cadavers. We used bulk staining with green calcein as a fluorochrome. The microcracks were quantified in three 100-μm-thick sections using optic microscopy and were confirmed by laser confocal microscopy. Microcrack frequency (number of microcracks/mm2 of bone tissue) was compared between treated women and controls using nonparametric tests. We also explored predictors of microcrack frequency, including age, duration of BP therapy, and activation frequency.
Results: Among treated women, cancellous bone microcrack frequency was low (mean, 0.13 microcracks/mm2) and did not differ significantly from that observed in controls (0.05 microcracks/mm2; p = 0.59). Of note, 54% of the treated women and 58% of the controls had no observable microcracks. There was no association between microcrack frequency and the duration of BP therapy (for microcracks/mm2 and duration, Spearman r = 0.04, p = 0.80) and between patients' ages and the number of microcracks (Spearman r = −0.09, p = 0.61). Although bone remodeling parameters were suppressed in treated women, we found no relationship between microcrack density and activation frequency (Spearman r = −0.003, p = 0.99). Also, microcrack frequency was not increased in women with prevalent vertebral fracture compared with those without fractures.
Conclusions: Among postmenopausal osteoporotic women on long-term BPs, microcrack frequency in the iliac bone is low, despite a marked reduction of bone turnover.
Patterns of Men’s Use of Sexual and Reproductive Health Services
Authors: Kalmuss Debra , Tatum Carrie 
Published: June 2007

CONTEXT:  Men have been neglected as a target population for sexual and reproductive health services. As a result, little is known about the rates and antecedents of men’s service utilization. METHODS:  Data from the 2002 National Survey of Family Growth were used to examine utilization of sexual and reproductive health services among 3,611 men aged 20–44 who had ever had sex with a woman. Associations between demographic and behavioral variables and measures of service utilization were assessed in univariate and logistic regression analyses. RESULTS:  Only 48% of men reported receiving sexual and reproductive health services in the past year. The testicular exam was the most commonly received service (35%), but half of men who had had a testicular exam had received no other sexual and reproductive health services. Levels of unmet need for services among men engaging in sexual risk behaviors were substantial (32–63%). The odds of having received nontesticular services were elevated among men who were nonwhite and older, engaged in sexual risk behaviors, had had a physical exam and had public health insurance. The odds of having received only a testicular exam were elevated among men who were white, had lower levels of sexual risk, had had a physical exam and had private or no insurance. CONCLUSIONS:  Men who have sex with women are not receiving adequate levels of sexual and reproductive health care, and the care they receive is neither comprehensive nor integrated. Standards of clinical care need to be defined and communicated to men and providers.
I Wanna Hold Your Hand: The Progression of Social, Romantic and Sexual Events in Adolescent Relationships
Authors: O’Sullivan Lucia F. , Cheng Mariah Mantsun , Harris Kathleen Mullan , Brooks‐Gunn Jeanne 
Published: June 2007

CONTEXT:  Despite the vast amount of existing research on adolescent sexual behavior, little is known about the trajectory of social, romantic and sexual events within an adolescent’s relationship. METHODS:  A subsample of participants in Wave 2 of the National Longitudinal Study of Adolescent Health (8,438 respondents aged 12–21) provided data on the sequence of 15 social, romantic and sexual events that occurred in a recent romantic relationship. Proportions reporting each event and average relative rankings were assessed for all respondents, for different racial and ethnic groups, and for respondents who belonged to the same racial or ethnic group as their partner. Logistic regression was used to compare proportions; ordinary least square regression was used to analyze the mean sequential ranking of each event. RESULTS:  Social and romantic events, such as spending time with one’s partner in a group and holding hands, were far more common than sexual events, such as touching one’s partner without clothing, and typically preceded sexual events in the trajectory of relationship events. Romantic events were the most common across three of the four major U.S. racial and ethnic groups. Asian and Hispanic respondents tended to have low proportions reporting sexual events compared with white respondents. Black adolescents were the only group for whom talking about prevention of pregnancy and STDs preceded sexual events. Reports from male and female adolescents were similar. CONCLUSION:  Recognition of the diversity of relationship experiences may prompt the development of more effective interventions for adolescents who engage in risky sexual behavior.
Proximate Composition and Collagen Concentration of Processing Residue of Channel Catfish
Authors: Li Menghe H , Robinson Edwin H , Oberle Daniel F , Bosworth Brian G 
Published: June 2007

Abstract
Residues—including heads, skin, viscera, frames, and trimmings—from the channel catfish Ictalurus punctatus processing industry have generally been made into catfish meal and catfish oil that are used in animal feeds. There may be more efficient uses for these materials, such as producing collagen and other products. A study was conducted to determine the percentages of each component of the processing residue relative to whole fish weight and their crude protein, crude fat, moisture, ash, and collagen concentrations. Of a market-size channel catfish, the head accounted for 24% of the whole weight, the frame 13.6%, the viscera 10.8%, the skin 4.7%, and the trimmings 3.7%. These processing residues represent a total of 56.8% of the total fish weight. The highest crude protein and collagen concentrations were found in the skin (protein, 19.9% of wet tissue and 82.1% of dry matter; collagen, 14.2% of wet tissue and 58.7% of dry matter). The viscera had the highest fat level (32.7% of wet tissue and 69.6% of dry matter). The head remnants had the highest ash concentration (6.9% of wet tissue and 19.9% of dry matter). The skin had a high collagen concentration and is therefore a good candidate for collagen production.
Preliminary Investigations of Hydrogen Peroxide Treatment of Selected Ornamental Fishes and Efficacy against External Bacteria and Parasites in Green Swordtails
Authors: Russo Riccardo , Curtis Eric W. , Yanong Roy P. E. 
Published: June 2007

Abstract
The objectives of these preliminary studies were to evaluate the use of hydrogen peroxide (H2O2) for the treatment of selected species of ornamental fishes and its efficacy in treating external bacteria and parasites. In the first part of the study, fish of five species (serpae tetra Hyphessobrycon eques (also known as Serpa tetra H. serpae), tiger barb Puntius tetrazona, blue gourami Trichogaster trichopterus, suckermouth catfish Hypostomus plecostomus, and green swordtail Xiphophorus hellerii) were exposed to H2O2 for 1 h at concentrations between 6 and 34 mg/L or for 24 h at concentrations between 1 and 6 mg/L. The results were species specific: green swordtails tolerated all of the treatments, serpae tetras and tiger barbs were sensitive only to the highest concentration, and mortalities of suckermouth catfish and blue gourami were recorded in every treatment. In the second part of the study, clinically healthy green swordtails and fish infested with external motile rod-shaped bacteria (i.e., Ichthyobodo spp., Trichodina spp., and Gyrodactylus spp.) were treated with several concentrations of H2O2. A single H2O2 treatment of 3.1 mg/L or more for 1 h effectively eliminated external bacteria, concentrations of 6.5 mg/L or more appeared to effectively kill Ichthyobodo spp., and none of the treatments tested was effective against Trichodina spp. or Gyrodactylus spp. These preliminary findings suggest that H2O2 is effective for treating certain external bacterial infections and flagellate infestations in some species of ornamental fish at the dosages tested. Other treatment regimens may need to be tested for effectiveness against Trichodina spp. and Dactylogyrus spp.
Genetic and Environmental Influences on Life History Traits in Lake Trout
Authors: McDermid Jenni L. , Ihssen Peter E. , Sloan William N. , Shuter Brian J. 
Published: June 2007

AbstractLake trout Salvelinus namaycush exhibit substantial life history variation associated with variation in climatic and biotic variables. To assess the environmental and genetic influences on lake trout life history traits, eggs were collected from two lakes in Algonquin Park, Ontario, Lake Opeongo and Louisa Lake, with contrasting ecotypes and forage bases. Eggs from both populations and interpopulation hybrids (Lake Opeongo females × Louisa Lake males) were raised to maturity in a common controlled environment. There was evidence of a genetic basis to life history variation between ecotypes. Hatchery‐reared lake trout from Louisa Lake were found to have a faster prematuration growth rate and earlier age and smaller size at maturation than Lake Opeongo lake trout, whereas Lake Opeongo lake trout had greater postmaturation growth rates. Most of the life history traits of hybrids were intermediate between those of the parent populations. These differences were also consistent with reported differences on these populations in the field. Despite differences in maturation and body size, reproductive investment did not differ significantly among the hatchery‐reared populations. There was also evidence of phenotypic plasticity in growth (juvenile and adult) and age at maturity. For fish originating from each lake, hatchery‐raised fish showed higher prematuration growth rates and younger ages at maturity than did wild fish. Hatchery‐reared fish from Louisa Lake were projected to attain asymptotic sizes nearly 50% larger than those of their wild counterparts. These data provide evidence that wild lake trout populations exhibit a plastic response to resource limitation. The combined results of this study indicate that lake trout life history characteristics are driven by both genetic and environmental influences, which should be incorporated into current life history models and used in making management decisions.
Consideration of aggressive therapeutic strategies for primary testicular lymphoma
Authors: Park Byeong‐Bae , Kim Jong Gwang , Sohn Sang Kyun , Kang Hye Jin , Lee Seung Sook , Eom Hyeon Seok , Kwon Hyuck Chan , Oh Sung Yong , Kang Jung Hun , Oh Suk Joong , Shin Ho‐Jin , Suh Cheolwon , Kim Jung Han , Kim Ho Young , Kim Kihyun , Ryoo Baek Yeol , Kim Won Seog 
Published: June 2007

AbstractTo evaluate the clinical features and treatment of primary testicular lymphoma, 45 cases were retrospectively evaluated. The median age of the patients was 59 years (range, 40–81) and most patients (76%) presented with Stages I–II. All patients underwent an orchiectomy, after which various treatments were given, chemotherapy alone in 37 patients (60%) and chemotherapy with involved field radiotherapy (IFRT) in 15 patients (33%). Prophylactic intrathecal chemotherapy was given to six patients; cranial irradiation was given in two patients. Eleven patients (24%) received prophylactic irradiation or surgery on the contralateral testis. In 40 patients able to be evaluated, complete response (CR) rate was 78%; 11 of 31 CR patients (36%) had relapsed. Relapse or disease progression was observed in 21 patients. The most frequent site (44%) was in the CNS. The median progression free survival and overall survival were 16 and 34 months, respectively. Ten patients who received prophylactic radiation to the contralateral testis had no relapse in this site. In six patients who received prophylactic intrathecal chemotherapy, there was no leptomeningeal progression, but brain parenchymal relapse occurred in two patients. In multivariate analysis, Stage I (P = 0.02) and additional IFRT after orchiectomy (P = 0.01) were found to be good prognostic factors. In conclusion, orchiectomy followed by intensive chemotherapy and IFRT including prophylaxis to the CNS and contralateral testis, should be considered as initial treatment in primary testicular lymphoma. Am. J. Hematol., 2007. © 2007 Wiley‐Liss, Inc.