bluuebunny/crossref_metadata_2025 huggingface dataset:
Human attitudes towards herpetofauna: The influence of folklore and negative values on the conservation of amphibians and reptiles in Portugal
Authors: Ceríaco Luis MP
Published: February 2012

Background

Human values and folklore of wildlife strongly influence the effectiveness of conservation efforts. These values and folklore may also vary with certain demographic characteristics such as gender, age, or education. Reptiles and amphibians are among the least appreciated of vertebrates and are victims of many negative values and wrong ideas resulting from the direct interpretation of folklore. We try to demonstrate how these values and folklore can affect the way people relate to them and also the possible conservation impacts on these animals.

Methods

A questionnaire survey distributed to 514 people in the district of Évora, Portugal, was used to obtain data regarding the hypothesis that the existence of wrong ideas and negative values contributes to the phenomenon of human-associated persecution of these animals. A structural equation model was specified in order to confirm the hypothesis about the possible relationships between the presence of perceptions and negative values about amphibians and reptiles and persecution and anti-conservation attitudes. Sociodemographic variables were also added.

Results

The results of the model suggest that the presence of folklore and negative values clearly predicts persecution and anti-conservation attitudes towards amphibians and reptiles. Also, the existence of folklore varies sociodemographically, but negative values concerning these animals are widespread in the population.

Conclusions

With the use of structural equation models, this work is a contribution to the study of how certain ideas and values can directly influence human attitudes towards herpetofauna and how they can be a serious conservation issue.
Biological conversion assay using Clostridium phytofermentans to estimate plant feedstock quality
Authors: Lee Scott J , Warnick Thomas A , Pattathil Sivakumar , Alvelo-Maurosa Jesús G , Serapiglia Michelle J , McCormick Heather , Brown Virginia , Young Naomi F , Schnell Danny J , Smart Lawrence B , Hahn Michael G , Pedersen Jeffrey F , Leschine Susan B , Hazen Samuel P
Published: February 2012

Background

There is currently considerable interest in developing renewable sources of energy. One strategy is the biological conversion of plant biomass to liquid transportation fuel. Several technical hurdles impinge upon the economic feasibility of this strategy, including the development of energy crops amenable to facile deconstruction. Reliable assays to characterize feedstock quality are needed to measure the effects of pre-treatment and processing and of the plant and microbial genetic diversity that influence bioconversion efficiency.

Results

We used the anaerobic bacterium Clostridium phytofermentans to develop a robust assay for biomass digestibility and conversion to biofuels. The assay utilizes the ability of the microbe to convert biomass directly into ethanol with little or no pre-treatment. Plant samples were added to an anaerobic minimal medium and inoculated with C. phytofermentans, incubated for 3 days, after which the culture supernatant was analyzed for ethanol concentration. The assay detected significant differences in the supernatant ethanol from wild-type sorghum compared with brown midrib sorghum mutants previously shown to be highly digestible. Compositional analysis of the biomass before and after inoculation suggested that differences in xylan metabolism were partly responsible for the differences in ethanol yields. Additionally, we characterized the natural genetic variation for conversion efficiency in Brachypodium distachyon and shrub willow (Salix spp.).

Conclusion

Our results agree with those from previous studies of lignin mutants using enzymatic saccharification-based approaches. However, the use of C. phytofermentans takes into consideration specific organismal interactions, which will be crucial for simultaneous saccharification fermentation or consolidated bioprocessing. The ability to detect such phenotypic variation facilitates the genetic analysis of mechanisms underlying plant feedstock quality.
PinX1 regulation of telomerase activity and apoptosis in nasopharyngeal carcinoma cells
Authors: Lai Xiao-Fen , Shen Cong-Xiang , Wen Zhong , Qian Yu-Hong , Yu Chao-Sheng , Wang Jun-Qi , Zhong Ping-Neng , Wang Hai-Li
Published: February 2012

Background

Human interacting protein X1 (PinX1) has been identified as a critical telomerase inhibitor and proposed to be a putative tumor suppressor gene. Loss of PinX1 has been found in a large variety of malignancies, however, its function in inhibiting telomerase activity of tumor cells is not well documented. Here we show that PinX1 is essential for down-regulation telomerase activity of nasopharyngeal carcinoma.

Methods

Expression vectors of human PinX1 (pEGFP-C3-PinX1) and its small interfering RNA (PinX1-FAM-siRNA) were constructed and transfected into NPC. Their effects on mRNA of telomerase catalytic subunit (hTERT), telomerase activity, cell proliferation, cell migration, wound healing, cell cycles and apoptosis were examined using semi-quantitative RT-PCR, stretch PCR, MTT assay, Transwell, scratch assay and flow cytometry, respectively.

Results

Transfection of pEGFP-C3-PinX1 and PinX1-FAM-siRNA increased and reduced PinX1 mRNA by 1.6-fold and 70%, respectively. Over-expression of PinX1 decreased hTERT mRNA by 21%, reduced telomerase activity, inhibited cell growth, migration and wound healing ability, arrested cells in G0/G1 phase, and increased apoptotic index. In contrast, down-regulation of PinX1 did not alter the above characteristics.

Conclusions

PinX1 may play important roles in NPC proliferation, migration and apoptosis and has application potential in tumor-targeted gene therapy.
The clinical use of biomarkers as prognostic factors in Ewing sarcoma
Authors: van Maldegem Annmeik M , Hogendoorn Pancras CW , Hassan Andrew B
Published: February 2012

Ewing Sarcoma is the second most common primary bone sarcoma with 900 new diagnoses per year in Europe (EU27). It has a poor survival rate in the face of metastatic disease, with no more than 10% survival of the 35% who develop recurrence. Despite the remaining majority having localised disease, approximately 30% still relapse and die despite salvage therapies. Prognostic factors may identify patients at higher risk that might require differential therapeutic interventions. Aside from phenotypic features, quantitative biomarkers based on biological measurements may help identify tumours that are more aggressive. We audited the research which has been done to identify prognostic biomarkers for Ewing sarcoma in the past 15 years. We identified 86 articles were identified using defined search criteria. A total of 11,625 patients were reported, although this number reflects reanalysis of several cohorts. For phenotypic markers, independent reports suggest that tumour size > 8 cm and the presence of metastasis appeared strong predictors of negative outcome. Good histological response (necrosis > 90%) after treatment appeared a significant predictor for a positive outcome. However, data proposing biological biomarkers for practical clinical use remain un-validated with only one secondary report published. Our recommendation is that we can stratify patients according to their stage and using the phenotypic features of metastases, tumour size and histological response. For biological biomarkers, we suggest a number of validating studies including markers for 9p21 locus, heat shock proteins, telomerase related markers, interleukins, tumour necrosis factors, VEGF pathway, lymphocyte count, and a number of other markers including Ki-67.
Histone deacetylase inhibitors enhance expression of NKG2D ligands in Ewing sarcoma and sensitize for natural killer cell-mediated cytolysis
Authors: Berghuis Dagmar , Schilham Marco W , Vos Hanneke I , Santos Susy J , Kloess Stephan , Buddingh' Emilie P , Egeler R Maarten , Hogendoorn Pancras CW , Lankester Arjan C
Published: February 2012

Background

Ewing sarcoma patients have a poor prognosis despite multimodal therapy. Integration of combination immunotherapeutic strategies into first-/second-line regimens represents promising treatment options, particularly for patients with intrinsic or acquired resistance to conventional therapies. We evaluated the susceptibility of Ewing sarcoma to natural killer cell-based combination immunotherapy, by assessing the capacity of histone deacetylase inhibitors to improve immune recognition and sensitize for natural killer cell cytotoxicity.

Methods

Using flow cytometry, ELISA and immunohistochemistry, expression of natural killer cell receptor ligands was assessed in chemotherapy-sensitive/-resistant Ewing sarcoma cell lines, plasma and tumours. Natural killer cell cytotoxicity was evaluated in Chromium release assays. Using ATM/ATR inhibitor caffeine, the contribution of the DNA damage response pathway to histone deacetylase inhibitor-induced ligand expression was assessed.

Results

Despite comparable expression of natural killer cell receptor ligands, chemotherapy-resistant Ewing sarcoma exhibited reduced susceptibility to resting natural killer cells. Interleukin-15-activation of natural killer cells overcame this reduced sensitivity. Histone deacetylase inhibitor-pretreatment induced NKG2D-ligand expression in an ATM/ATR-dependent manner and sensitized for NKG2D-dependent cytotoxicity (2/4 cell lines). NKG2D-ligands were expressed in vivo, regardless of chemotherapy-response and disease stage. Soluble NKG2D-ligand plasma concentrations did not differ between patients and controls.

Conclusion

Our data provide a rationale for combination immunotherapy involving immune effector and target cell manipulation in first-/second-line treatment regimens for Ewing sarcoma.
Clustering of HIV-1 Subtypes Based on gp120 V3 Loop electrostatic properties
Authors: López de Victoria Aliana , Kieslich Chris A , Rizos Apostolos K , Krambovitis Elias , Morikis Dimitrios
Published: February 2012

Background

The V3 loop of the glycoprotein gp120 of HIV-1 plays an important role in viral entry into cells by utilizing as coreceptor CCR5 or CXCR4, and is implicated in the phenotypic tropisms of HIV viruses. It has been hypothesized that the interaction between the V3 loop and CCR5 or CXCR4 is mediated by electrostatics. We have performed hierarchical clustering analysis of the spatial distributions of electrostatic potentials and charges of V3 loop structures containing consensus sequences of HIV-1 subtypes.

Results

Although the majority of consensus sequences have a net charge of +3, the spatial distribution of their electrostatic potentials and charges may be a discriminating factor for binding and infectivity. This is demonstrated by the formation of several small subclusters, within major clusters, which indicates common origin but distinct spatial details of electrostatic properties. Some of this information may be present, in a coarse manner, in clustering of sequences, but the spatial details are largely lost. We show the effect of ionic strength on clustering of electrostatic potentials, information that is not present in clustering of charges or sequences. We also make correlations between clustering of electrostatic potentials and net charge, coreceptor selectivity, global prevalence, and geographic distribution. Finally, we interpret coreceptor selectivity based on the N6X7T8|S8X9sequence glycosylation motif, the specific positive charge location according to the 11/24/25 rule, and the overall charge and electrostatic potential distribution.

Conclusions

We propose that in addition to the sequence and the net charge of the V3 loop of each subtype, the spatial distributions of electrostatic potentials and charges may also be important factors for receptor recognition and binding and subsequent viral entry into cells. This implies that the overall electrostatic potential is responsible for long-range recognition of the V3 loop with coreceptors CCR5/CXCR4, whereas the charge distribution contributes to the specific short-range interactions responsible for the formation of the bound complex. We also propose a scheme for coreceptor selectivity based on the sequence glycosylation motif, the 11/24/25 rule, and net charge.
Advances in on-sea-ice seismic reflection methods using an air gun: McMurdo Sound, Antarctica
Authors: Sunwall David A. , Speece Marvin A. , Pekar Stephen F.
Published: February 2012

During the austral spring of 2008, 48 km of multichannel seismic reflection data were collected on a sea-ice platform east of New Harbor, Southern McMurdo Sound, Antarctica. These seismic data were collected to support the Antarctic Geological Drilling Program whose goal is to recover sedimentary rock cores from the continental margin of Antarctica and to better understand the climatic, cryospheric, and tectonic history of Antarctica. A Generator-Injector air gun, deployed through holes drilled in the sea ice, was used for a seismic source, and reflected energy was recorded on a snow streamer consisting of 60 gimbaled geophones. The Offshore New Harbor seismic system has increased the rate of data acquisition by 53% compared to previous Antarctic air-gun/snow-streamer seismic systems. In addition to conventional on-sea-ice seismic data processing, new processing steps were used to correct problems associated with the use of a Generator-Injector air gun in a sea-ice environment. Source timing errors, caused by miscommunications between the Generator-Injector air gun and air-gun controller, were corrected. Newly discovered bubble-plume static errors and bubble-plume wavelet distortions degraded seismic data quality and are attributed to bubble plumes created by the Generator-Injector air-gun blast. Our investigation shows that these bubble plumes were preserved for at least 40 hours beneath the sea ice and created isolated low-velocity zones. Using finite-element methods, we reproduced static errors and wavelet distortions by incorporating the effects of bubble plumes into the finite-element model. The results of finite-element modeling confirmed our hypothesis that bubble-plume static errors and bubble-plume wavelet distortions were caused by near-surface low-velocity features. Therefore, we incorporated new processing steps which remove bubble-plume effects and improve the quality of final seismic sections.
Suppressing nonphysical reflections in Green’s function estimates using source-receiver interferometry
Authors: King Simon , Curtis Andrew
Published: February 2012

Seismic interferometry retrieves the Green’s function propagating between two receiver locations using their recordings from an enclosing boundary of sources. Theory requires that sources completely surround the two receivers, but constraints in exploration seismology restrict sources to locations near the surface of the earth. Seismic interferometry by crosscorrelation then introduces usually undesirable nonphysical reflections (spurious multiples) in the Green’s function estimates. We found that the dominant nonphysical reflections can be converted into physical reflections via convolution using source-receiver interferometry. The resultant Green’s functions display fewer nonphysical reflections and show significantly better agreement with the true Green’s functions than those obtained using crosscorrelational interferometry. Nonphysical reflections can be further suppressed by iterating the convolution step. By comparing the velocity spectra of the Green’s functions retrieved by crosscorrelational and source-receiver interferometry, we can retrospectively identify the dominant nonphysical reflections introduced by crosscorrelational interferometry. We found that the nonphysical reflections are particularly important for constructing the primary reflections and internal multiples in source-receiver interferometry. This is because the primary reflections and internal multiples cannot be created via the convolution of physical reflections. Instead, the primary reflections and internal multiples are retrieved by the appropriate convolution between a nonphysical and physical reflection. We compared crosscorrelational interferometry and source-receiver interferometry using synthetic towed streamer data for a 1D acoustic and 2.5D elastic model, respectively. We also found that the nonphysical reflections obtained using crosscorrelational interferometry allow for the direct estimation of interval velocities and layer thicknesses without the need to use Dix inversion in the 1D example.
Cortisol Induces Aromatase Expression in Human Placental Syncytiotrophoblasts Through the cAMP/Sp1 Pathway
Authors: Wang Wangsheng , Li Jianneng , Ge Yuchun , Li Wenjiao , Shu Qun , Guan Haiyan , Yang Kaiping , Myatt Leslie , Sun Kang
Published: February 2012

One of the dominant effects of glucocorticoids in triggering parturition in certain animal species is to drive the placental conversion of progesterone to estrogen. However, in the human placenta, estrogen is formed using dehydroepiandrosterone from the fetal adrenal glands rather than progesterone as precursor. Although aromatization of dehydroepiandrosterone is crucial in estrogen synthesis in human placenta, it is not known whether glucocorticoids affect aromatase expression. Human term placental syncytiotrophoblasts were used to examine the effect of cortisol on aromatase expression. The signaling pathway and transcription factors involved were identified in this study. Results showed that cortisol induced aromatase expression in a concentration-dependent manner, which was mediated indirectly by glucocorticoid receptor and required the participation of other proteins. The induction of aromatase by cortisol could be blocked by either specificity protein 1 (Sp1) antagonist mithramycin or knockdown of Sp1 expression. The induction of aromatase and Sp1 by cortisol could be prevented by inhibitors of the cAMP pathway, whereas activators of the cAMP pathway induced Sp1 and aromatase expression as well as Sp1 binding to aromatase promoter. Concomitantly, cortisol treatment and activation of the cAMP pathway led to increased acetylation and decreased methylation of histone 3 at the aromatase promoter. In conclusion, cortisol stimulates aromatase expression through the cAMP/Sp1 pathway in human placental syncytiotrophoblasts. These findings reveal a novel role of cortisol in increasing the local level of estrogen within the placenta that would help transform the myometrium to a contractile state, thereby contributing to a cascade of events leading to human parturition.
Potassium Channel Mutant KCNJ5 T158A Expression in HAC-15 Cells Increases Aldosterone Synthesis
Authors: Oki Kenji , Plonczynski Maria W. , Luis Lam Milay , Gomez-Sanchez Elise P. , Gomez-Sanchez Celso E.
Published: February 2012

Primary aldosteronism is the most common cause of secondary hypertension, most frequently due to an aldosterone-producing adenoma or idiopathic hyperaldosteronism. Somatic mutations of the potassium channel KCNJ5 in the region of the selectivity filter have been found in a significant number of aldosterone-producing adenomas. There are also familial forms of primary aldosteronism, one of which, familial hyperaldosteronism type 3 which to date has been found in one family who presented with a severe abnormality in aldosterone and 18-oxocortisol production and hypertrophy and hyperplasia of the transitional zone of the adrenal cortex. In familial hyperaldosteronism type 3, there is a genomic mutation causing a T158A change of amino acids within the selectivity filter region of the KCNJ5 gene.

We are reporting our studies demonstrating that lentiviral-mediated expression of a gene carrying the T158A mutation of the KCNJ5 in the HAC15 adrenal cortical carcinoma cell line causes a 5.3-fold increase in aldosterone secretion in unstimulated HAC15-KCNJ5 cells and that forskolin-stimulated aldosterone secretion was greater than that of angiotensin II. Expression of the mutated KCNJ5 gene decreases plasma membrane polarization, allowing sodium and calcium influx into the cells. The calcium channel antagonist nifedipine and the calmodulin inhibitor W-7 variably inhibited the effect. Overexpression of the mutated KCNJ5 channel resulted in a modest decrease in HAC15 cell proliferation.

These studies demonstrate that the T158A mutation of the KCNJ5 gene produces a marked stimulation in aldosterone biosynthesis that is dependent on membrane depolarization and sodium and calcium influx into the HAC15 adrenal cortical carcinoma cells.
Postnatal Aromatase Blockade Increases c-fos mRNA Responses to Acute Restraint Stress in Adult Male Rats
Authors: Bingham Brenda , Wang Nancy X. R. , Innala Leyla , Viau Victor
Published: February 2012

Recent evidence suggests that the aromatization of testosterone to estrogen is important for the organizing effects of neonatal testosterone on neuroendocrine responses to acute challenges. However, the extent to which neonatal inhibition of aromatase alters the stress-induced activation of neural pathways has not been examined. Here we assessed central patterns of c-fos mRNA induced by 30 min of restraint in 65-d-old adult male rats that were implanted with sc capsules of the aromatase inhibitor 1,4,6-androstatriene-3,17-dione (ATD), introduced within 12 h of birth and removed on d 21 of weaning. Neonatal ATD decreased the expression of arginine vasopressin within extrahypothalamic regions in adults, confirming reduced estrogen exposure during development. As adults, ATD-treated animals showed higher corticosterone responses at 30 min of restraint exposure compared with control animals as well as higher c-fos expression levels in the paraventricular nucleus of the hypothalamus. ATD treatment also increased stress-induced c-fos within several limbic regions of the forebrain, in addition to areas involved in somatosensory processing. Based on these results, we propose that the conversion of testosterone to estrogen during the neonatal period exerts marked, system-wide effects to organize adult neuroendocrine responses to homeostatic threat.
Estrogenic Action on Arterial Smooth Muscle: Permissive for Maintenance of CRHR2 Expression
Authors: Wang Shan , Zhu Xiaoyan , Cong Binhai , You Xingji , Wang Yangkai , Wang Weizhong , Ni Xin
Published: February 2012

Urocortin (Ucn), a member of CRH family, has been implicated to be one of the endogenous regulators in the cardiovascular system and exerts its effects locally via an autocrine/paracrine fashion. Previous studies have shown the gender difference in CRH-induced vasodilation in human skin, which is related to the concentration of estrogens during the menstrual cycle. The aim of this study was to investigate whether estrogens modulate Ucn/CRH receptor type 2 (CRHR2) expression in vascular smooth muscle, thereby leading to vasodilation. We performed sham operation or bilateral ovariectomy (OVX) on female Sprague Dawley rats. OVX rats were sc administered 17β-estradiol (E2) at a dose of 30 μg/kg·d or with placebo for 12 wk. Primary smooth muscle cells of aorta were used for the in vitro study. It was found that the Ucn-induced vasodilation and CRHR2 expression were decreased in OVX rats and restored by E2 replacement treatment for 12 wk. E2 increased the expression of CRHR2 in cultured smooth muscle cells, which was blocked by estrogen receptor-β antagonist. Ucn significantly suppressed the phenylephrine-induced phospholipase Cβ3 activation, inositol 1,4,5-trisphosphate (IP3) production, and intracellular Ca2+ elevation. Ucn stimulated the expression of active GTP-bound Gαs protein and cAMP production. The suppressive effects of Ucn on phenylephrine-induced IP3 production and intracellular Ca2+ elevation were blocked by the inhibitors of adenylate cyclase and protein kinase A. Our results demonstrate that estrogen maintains the expression of CRHR2 in aorta smooth muscle, thereby enhancing vasodilator actions of Ucn. Ucn exerts its vasorelaxant effects via Gαs-cAMP-protein kinase A signaling, leading to down-regulation of the phospholipase Cβ-IP3-Ca2+ signaling pathway.
Stable isotope tracer reveals that viviparous snakes transport amino acids to offspring during gestation
Authors: Van Dyke James U. , Beaupre Steven J.
Published: February 2012

Viviparity and placentation have evolved from oviparity over 100 times in squamate reptiles (lizards and snakes). The independent origins of placentation have resulted in a variety of placental morphologies in different taxa, ranging from simple apposition of fetal and maternal tissues to endotheliochorial implantation that is homoplasious with mammalian placentation. Because the eggs of oviparous squamates transport gases and water from the environment and calcium from the eggshell, the placentae of viviparous squamates are thought to have initially evolved to accomplish these functions from within the maternal oviduct. Species with complex placentae have also been shown to rely substantially, or even primarily, on placental transport of organic nutrients for embryonic nutrition. However, it is unclear whether species with only simple placentae are also capable of transporting organic nutrients to offspring. Among viviparous squamates, all of the snakes that have been studied thus far have been shown to have simple placentae. However, most studies of snake placentation are limited to a single lineage, the North American Natricinae. We tested the abilities of four species of viviparous snakes – Agkistrodon contortrix (Viperidae), Boa constrictor (Boidae), Nerodia sipedon (Colubridae: Natricinae) and Thamnophis sirtalis (Colubridae: Natricinae) – to transport diet-derived amino acids to offspring during gestation. We fed [15N]leucine to pregnant snakes, and compared offspring 15N content with that of unlabeled controls. Labeled females allocated significantly more 15N to offspring than did controls, but 15N allocation did not differ among species. Our results indicate that viviparous snakes are capable of transporting diet-derived amino acids to their offspring during gestation, possibly via placentation.
In the face of hypoxia: myoglobin increases in response to hypoxic conditions and lipid supplementation in cultured Weddell seal skeletal muscle cells
Authors: De Miranda Michael A. , Schlater Amber E. , Green Todd L. , Kanatous Shane B.
Published: February 2012

A key cellular adaptation to diving in Weddell seals is enhanced myoglobin concentrations in their skeletal muscles, which serve to store oxygen to sustain a lipid-based aerobic metabolism. The aim of this study was to determine whether seal muscle cells are inherently adapted to possess the unique skeletal muscle adaptations to diving seen in the whole animal. We hypothesized that the seal skeletal muscle cells would have enhanced concentrations of myoglobin de novo that would be greater than those from a C2C12 skeletal muscle cell line and reflect the concentrations of myoglobin observed in previous studies. In addition we hypothesized that the seal cells would respond to environmental hypoxia similarly to the C2C12 cells in that citrate synthase activity and myoglobin would remain the same or decrease under hypoxia and lactate dehydrogenase activity would increase under hypoxia as previously reported. We further hypothesized that β-hydroxyacyl CoA dehydrogenase activity would increase in response to the increasing amounts of lipid supplemented to the culture medium. Our results show that myoglobin significantly increases in response to environmental hypoxia and lipids in the Weddell seal cells, while appearing similar metabolically to the C2C12 cells. The results of this study suggest the regulation of myoglobin expression is fundamentally different in Weddell seal skeletal muscle cells when compared with a terrestrial mammalian cell line in that hypoxia and lipids initially prime the skeletal muscles for enhanced myoglobin expression. However, the cells need a secondary stimulus to further increase myoglobin to levels seen in the whole animal.
The accessory role of the diaphragmaticus muscle in lung ventilation in the estuarine crocodile Crocodylus porosus
Authors: Munns Suzanne L. , Owerkowicz Tomasz , Andrewartha Sarah J. , Frappell Peter B.
Published: February 2012

Crocodilians use a combination of three muscular mechanisms to effect lung ventilation: the intercostal muscles producing thoracic movement, the abdominal muscles producing pelvic rotation and gastralial translation, and the diaphragmaticus muscle producing visceral displacement. Earlier studies suggested that the diaphragmaticus is a primary muscle of inspiration in crocodilians, but direct measurements of the diaphragmatic contribution to lung ventilation and gas exchange have not been made to date. In this study, ventilation, metabolic rate and arterial blood gases were measured from juvenile estuarine crocodiles under three conditions: (i) while resting at 30°C and 20°C; (ii) while breathing hypercapnic gases; and (iii) during immediate recovery from treadmill exercise. The relative contribution of the diaphragmaticus was then determined by obtaining measurements before and after transection of the muscle. The diaphragmaticus was found to make only a limited contribution to lung ventilation while crocodiles were resting at 30°C and 20°C, and during increased respiratory drive induced by hypercapnic gas. However, the diaphragmaticus muscle was found to play a significant role in facilitating a higher rate of inspiratory airflow in response to exercise. Transection of the diaphragmaticus decreased the exercise-induced increase in the rate of inspiration (with no compensatory increases in the duration of inspiration), thus compromising the exercise-induced increases in tidal volume and minute ventilation. These results suggest that, in C. porosus, costal ventilation alone is able to support metabolic demands at rest, and the diaphragmaticus is largely an accessory muscle used at times of elevated metabolic demand.
Net superoxide levels: steeper increase with activity in cooler female and hotter male lizards
Authors: Ballen Cissy , Healey Mo , Wilson Mark , Tobler Michael , Wapstra Erik , Olsson Mats
Published: February 2012

Ectotherms increase their body temperature in response to ambient heat, thereby elevating their metabolic rate. An often inferred consequence of this is an overall upregulation of gene expression and energetic expenditure, and a concomitant increased production of reactive oxygen species (e.g. superoxide) and, perhaps, a shortened lifespan. However, recent work shows that this may be a superficial interpretation. For example, sometimes a reduced temperature may in fact trigger up-regulation of gene expression. We studied temperature and associated activity effects in male and female Australian painted dragon lizards (Ctenophorus pictus) by allowing the lizards to bask for 4 h versus 12 h, and scoring their associated activity (inactive versus active basking and foraging). As predicted, long-basking lizards (hereafter ‘hot’) showed heightened activity in both sexes, with a more pronounced effect in females. We then tested for sex-specific effects of basking treatment and activity levels on the increase in net levels of superoxide. In males, short-baskers (hereafter ‘cold’) had significantly more rapidly decreasing levels of superoxide per unit increasing activity than hot males. In females, however, superoxide levels increased faster with increasing activity in the cold than in the hot basking treatment, and females earlier in the ovarian cycle had lower superoxide levels than females closer to ovulation. In short, males and females differ in how their levels of reactive oxygen species change with temperature-triggered activity.
How to make a sexy snake: estrogen activation of female sex pheromone in male red-sided garter snakes
Authors: Parker M. Rockwell , Mason Robert T.
Published: February 2012

Vertebrates indicate their genetic sex to conspecifics using secondary sexual signals, and signal expression is often activated by sex hormones. Among vertebrate signaling modalities, the least is known about how hormones influence chemical signaling. Our study species, the red-sided garter snake (Thamnophis sirtalis parietalis), is a model vertebrate for studying hormonal control of chemical signals because males completely rely on the female sex pheromone to identify potential mates among thousands of individuals. How sex hormones can influence the expression of this crucial sexual signal is largely unknown. We created two groups of experimental males for the first experiment: Sham (blank implants) and E2 (17β-estradiol implants). E2 males were vigorously courted by wild males in outdoor bioassays, and in a Y-maze E2 pheromone trails were chosen by wild males over those of small females and were indistinguishable from large female trails. Biochemically, the E2 pheromone blend was similar to that of large females, and it differed significantly from Shams. For the second experiment, we implanted males with 17β-estradiol in 2007 but removed the implants the following year (2008; Removal). That same year, we implanted a new group of males with estrogen implants (Implant). Removal males were courted by wild males in 2008 (implant intact) but not in 2009 (removed). Total pheromone quantity and quality increased following estrogen treatment, and estrogen removal re-established male-typical pheromone blends. Thus, we have shown that estrogen activates the production of female pheromone in adult red-sided garter snakes. This is the first known study to quantify both behavioral and biochemical responses in chemical signaling following sex steroid treatment of reptiles in the activation/organization context. We propose that the homogametic sex (ZZ, male) may possess the same targets for activation of sexual signal production, and the absence of the activator (17β-estradiol in this case) underlies expression of the male phenotype.
Is solid always best? Cranial performance in solid and fenestrated caecilian skulls
Authors: Kleinteich Thomas , Maddin Hillary C. , Herzen Julia , Beckmann Felix , Summers Adam P.
Published: February 2012

Caecilians (Lissamphibia: Gymnophiona) are characterized by a fossorial lifestyle that appears to play a role in the many anatomical specializations in the group. The skull, in particular, has been the focus of previous studies because it is driven into the substrate for burrowing. There are two different types of skulls in caecilians: (1) stegokrotaphic, where the squamosal completely covers the temporal region and the jaw closing muscles, and (2) zygokrotaphic, with incomplete coverage of the temporal region by the squamosal. We used 3-D imaging and modeling techniques to explore the functional consequences of these skull types in an evolutionary context. We digitally converted stegokrotaphic skulls into zygokrotaphic skulls and vice versa. We also generated a third, akinetic skull type that was presumably present in extinct caecilian ancestors. We explored the benefits and costs of the different skull types under frontal loading at different head angles with finite element analysis (FEA). Surprisingly, the differences in stress distributions and bending between the three tested skull types were minimal and not significant. This suggests that the open temporal region in zygokrotaphic skulls does not lead to poorer performance during burrowing. However, the results of the FEA suggest a strong relationship between the head angle and skull performance, implying there is an optimal head angle during burrowing.
Optimal Interventions in Markets with Adverse Selection
Authors: Philippon Thomas , Skreta Vasiliki
Published: February 2012

We study the design of interventions to stabilize financial markets plagued by adverse selection. Our contribution is to analyze the information revealed by participation decisions. Taking part in a government program carries a stigma, and outside options are mechanism dependent. We show that the efficiency of an intervention can be assessed by its impact on the market interest rate. The presence of an outside market determines the nature of optimal interventions and the choice of financial instruments (debt guarantees in our model), but it does not affect implementation costs. (JEL D82, D86, G01, G20, G31)
Understanding International Prices: Customers as Capital
Authors: Drozd Lukasz A , Nosal Jaromir B
Published: February 2012

The article develops a new theory of pricing to market driven by dynamic frictions of building market shares. Our key innovation is a capital theoretic model of marketing in which relations with customers are valuable. We discipline the introduced friction using data on differences between short-run and long-run price elasticity of international trade flows. We show that the model accounts for several pricing “puzzles” of international macroeconomics. (JEL E13, F14, F31, F41, F44, M31)
Compulsory Licensing: Evidence from the Trading with the Enemy Act
Authors: Moser Petra , Voena Alessandra
Published: February 2012

Compulsory licensing allows firms in developing countries to produce foreign-owned inventions without the consent of foreign patent owners. This paper uses an exogenous event of compulsory licensing after World War I under the Trading with the Enemy Act to examine the effects of compulsory licensing on domestic invention. Difference-in-differences analyses of nearly 130,000 chemical inventions suggest that compulsory licensing increased domestic invention by 20 percent. (JEL D45, L24, N42, O31, O34)
Testing Efficient Risk Sharing with Heterogeneous Risk Preferences
Authors: Mazzocco Maurizio , Saini Shiv
Published: February 2012

We propose a method that enables one to test efficient risk sharing even when households have different risk preferences. The method is composed of three tests. The first one determines whether in the data households have homogeneous risk preferences. The second and third tests evaluate efficient risk sharing when the hypothesis of homogeneous risk preferences is rejected. We use this method to test efficient risk sharing in rural India. Using the first test, we strongly reject the hypothesis of identical risk preferences. Using the second and third tests, we reject efficiency at the village but not at the caste level. (JEL D12, D86, G22, O12, O18, R23, Z13)
A Structural Analysis of Disappointment Aversion in a Real Effort Competition
Authors: Gill David , Prowse Victoria
Published: February 2012

We develop a novel computerized real effort task, based on moving sliders across a screen, to test experimentally whether agents are disappointment averse when they compete in a real effort sequential-move tournament. We predict that a disappointment averse agent, who is loss averse around her endogenous choice-acclimating expectations-based reference point, responds negatively to her rival's effort. We find significant evidence for this discouragement effect, and use the Method of Simulated Moments to estimate the strength of disappointment aversion on average and the heterogeneity in disappointment aversion across the population. (JEL C91, D12, D81, D84)
Was the New Deal Contractionary?
Authors: Eggertsson Gauti B
Published: February 2012

Can government policies that increase the monopoly power of firms and the militancy of unions increase output? This paper shows that the answer is yes under certain “emergency” conditions. These emergency conditions—zero interest rates and deflation—were satisfied during the Great Depression in the United States. The New Deal, which facilitated monopolies and union militancy, was therefore expansionary in the model presented. This conclusion is contrary to a large previous literature. The main reason for this divergence is that this paper incorporates rigid prices and the zero bound on the short-term interest rate. JEL: E23, E32, E52, E62, J51, N12, N42
Collective Moral Hazard, Maturity Mismatch, and Systemic Bailouts
Authors: Farhi Emmanuel , Tirole Jean
Published: February 2012

The article shows that time-consistent, imperfectly targeted support to distressed institutions makes private leverage choices strategic complements. When everyone engages in maturity mismatch, authorities have little choice but intervening, creating both current and deferred (sowing the seeds of the next crisis) social costs. In turn, it is profitable to adopt a risky balance sheet. These insights have important consequences, from banks choosing to correlate their risk exposures to the need for macro-prudential supervision. (JEL D82, E52, E58, G01, G21, G28)
Efficient Pollution Regulation: Getting the Prices Right: Comment
Authors: Fraas Art , Lutter Randall
Published: February 2012

The cost-effectiveness of cap-and-trade emissions regulations has become widely accepted. A 2009 proposal by Muller and Mendelsohn would replace conventional ton-for-ton trading with trading based on estimates of marginal damages by pollutant and by source. This proposal faces difficulties arising from the negative marginal damage estimates—neglected in Muller and Mendelsohn (2009)—for nitrogen oxide (NOx) emissions from many urban counties. Such estimates imply nonconvexities in air chemistry that complicate trading and could result in trades that increase emissions by both buyer and seller. Uncertainty in source-specific damages also creates rent-seeking opportunities and the potential for costly litigation. JEL: H53, Q53, Q58
Can General Practitioner Commissioning Deliver Equity and Excellence? Evidence from Two Studies of Service Improvement in the English NHS
Authors: Gridley Kate , Spiers Gemma , Aspinal Fiona , Bernard Sylvia , Atkin Karl , Parker Gillian
Published: February 2012

Objectives

To explore some of the key assumptions underpinning the continued development of general practitioner-led commissioning in health services.

Methods

Qualitative data from two studies of service improvement in the English NHS were considered against England's plans for GP-led commissioning. These data were collected through in-depth interviews with a total of 187 professionals and 99 people affected by services in 10 different primary care trust areas across England between 2008 and 2009.

Results

Internationally, GPs are seen to have a central position in health systems. In keeping with this, the English policy places emphasis on the ‘pivotal role’ of general practitioners, considered to be ideally placed to commission in the best interests of their patients. However, our evidence suggests that general practitioners do not always have a pivotal role for all patients. Moreover, it is planned that the new commissioning groups in England will not be subject to top-down performance management and this raises the question of how agreed quality standards will be met under the proposed new system.

Conclusions

This paper questions the assumption that GPs are best placed to commission health services in a way that meets quality standards and leads to equitable outcomes. There is little evidence to suggest that GPs will succeed where others have failed and a risk that, without top-down performance management, service improvement will be patchy, leading to greater, not reduced, inequity.
Investigating the Governance of Autonomous Public Hospitals in England: Multi-Site Case Study of NHS Foundation Trusts
Authors: Allen Pauline , Keen Justin , Wright John , Dempster Paul , Townsend Jean , Hutchings Andrew , Street Andrew , Verzulli Rossella
Published: February 2012

Objective

To investigate the external and internal governance of NHS foundation trusts (FTs), which have increased autonomy, and local members and governors unlike other NHS trusts.

Methods

In depth, three-year case studies of four FTs; and analysis of national quantitative data on all FT hospitals and NHS Trust hospitals to give national context. Data included 111 interviews with managers, clinicians, governors and members, and local purchasers; observation of meetings; and analysis of FTs' documents.

Results

The four case study FTs were similar to other FTs. They had used their increased autonomy to develop more business-like practices. The FT regulator, Monitor, intervened only when there were reported problems in FT performance. National targets applying to the NHS also had a large effect on FT behaviour. FTs saw themselves as part of the local health economy and tried to maintain good relationships with local organisations. Relationships between governors and the FTs' executives were still developing, and not all governors felt able to hold their FT to account. The skills and experience of staff members and governors were under-used in the new governance structures.

Conclusions

It is easier to increase autonomy for public hospitals than to increase local accountability. Hospital managers are likely to be interested in making decisions with less central government control, whilst mechanisms for local accountability are notoriously difficult to design and operate. Further consideration of internal governance of FTs is needed. In a deteriorating financial climate, FTs should be better placed to make savings, due to their more business-like practices.
Wanda Ossowska (1912–2001) and Stanisława Leszczyńska (1896–1974): Polish nurses working under Nazi Occupation
Authors: Dobrowolska Barbara , Hoch Stefania , Jabkowska-Sochańska Aniela , Benedict Susan , Shields Linda
Published: February 2012

Poland was invaded by Nazi Germany on 1 September 1939 and World War II began on 3 September. Polish nurses have their place in this difficult history. In the first months of occupation, nurses focused on caring for wounded soldiers. In order to protect them from prisoner-of-war camps and execution, nurses sought safe havens for the wounded in private homes and transported them there. After their regular jobs, the nurses visited them, changed their dressings and provided them with civilian clothes so that soldiers could eventually escape. This paper describes the work of two of these nurses, Wanda Ossowska and Stanisława Leszczyńska. The first three authors (BD, SH, AJS) were nurses in Poland at that time and they present some of the information in this paper as primary source data.
Social and practical implications of fetal sex determination using ultrasound
Authors: Edwards Hazel , Thomson Nigel
Published: February 2012

Following recent debate on prenatal sex selection, the Council of Europe has resolved to encourage national ethics bodies to develop and introduce guidelines for medical staff discouraging prenatal sex selection by whatever means unless justified for the prevention of serious sex-linked genetic diseases. Ultrasound is the most common method for determining sex prenatally and is used for medical and social reasons. In some countries where male offspring are more desirable, fetal sexing during ultrasound examinations has been outlawed due to growing concern that large numbers of female fetuses are being terminated. Although Council of Europe decisions are not binding on the UK, it is timely to examine the use of ultrasound for the determination of fetal sex in the UK and to discuss some of the reasons behind why ultrasound cannot always get it right. We describe sex-linked conditions where sex identification is especially important and conditions and circumstances which make sexing difficult, including ambiguous genitalia. The social aspects of determining the sex of the fetus during an ultrasound examination are also explored as there is no doubt that many women want to know either from curiosity or to help plan for the new arrival. We recommend that ultrasound practitioners remain aware of the accuracy and limitations of ultrasound for the determination of fetal sex and should therefore exercise due caution when imparting sex information to parents.