bluuebunny/crossref_metadata_2025 huggingface dataset:
Single-well S-wave imaging using multicomponent dipole acoustic-log data
Authors: Tang Xiao-Ming , Patterson Douglas J.
Published: December 2009

Single-well S-wave imaging has several attractive features because of its directional sensitivity and usefulness for fracture characterization. To provide a method for single-well acoustic imaging, we analyzed the effects of wave radiation, reflection, and borehole acoustic response on S-wave reflection measurements from a multicomponent dipole acoustic tool. A study of S-wave radiation from a dipole source and the wave’s reflection from a formation boundary shows that the S-waves generated by a dipole source in a borehole have a wide radiation pattern that allows imaging of reflectors at various dip angles crossing the borehole. More importantly, the azimuthal variation of the S-waves, in connection with the multicomponent nature of a cross-dipole tool, can determine the strike of the reflector. We used our theoretical foundation for borehole S-wave imaging to formulate an inversion procedure for field data processing. Application to field data validates the theoretical results and demonstrates the advantages of S-wave imaging. Application to near-borehole fracture imaging clearly demonstrates S-wave azimuthal sensitivity to fracture orientation.
Fast 3D target-oriented reverse-time datuming
Authors: Dong Shuqian , Luo Yi , Xiao Xiang , Chávez-Pérez Sergio , Schuster Gerard T.
Published: December 2009

Imaging of subsalt sediments is a challenge for traditional migration methods such as Kirchhoff and one-way wave-equation migration. Consequently, the more accurate two-way method of reverse-time migration (RTM) is preferred for subsalt imaging, but its use can be limited by high computation cost. To overcome this problem, a 3D target-oriented reverse-time datuming (RTD) method is presented, which can generate redatumed data economically in target areas beneath complex structures such as salt domes. The redatumed data in the target area then can be migrated inexpensively using a traditional migration method. If the target area is much smaller than the acquisition area, computation costs are reduced significantly by the use of a novel bottom-up strategy to calculate the extrapolated Green’s functions. Target-oriented RTD is tested on 2D and 3D SEG/EAGE synthetic data sets and a 3D field data set from the Gulf of Mexico. Results show that target-oriented RTD combined with standard migration can image sediments beneath complex structures accurately with much less calculation effort than full volume RTM. The requirement is that the area over the target zone is smaller than that of the acquisition survey.
Direct downward continuation from topography using explicit wavefield extrapolation
Authors: Al-Saleh Saleh M. , Margrave Gary F. , Gray Sam H.
Published: December 2009

Downward-continuation migration algorithms are powerful tools for imaging complicated subsurface structures. However, they usually assume that extrapolation proceeds from a flat surface, whereas most land surveys are acquired over irregular surfaces. Our method downward continues data directly from topography using a recursive space-frequency explicit wavefield-extrapolation method. The algorithm typically handles strong lateral velocity variations by using the velocity value at each spatial position to build the wavefield extrapolator in which the depth step usually is kept fixed. To accommodate topographic variations, we build space-frequency wavefield extrapolators with laterally variable depth steps (LVDS). At each spatial location, the difference between topography and extrapolation depth is used to determine the depth step. We use the velocity and topographic values at each spatial lateral position to build extrapolators. The LVDS approach does not add more data nor does it require preprocessing prior to extrapolation. We implemented the LVDS method and applied it to a source profile prestack migration technique. We also implemented the previously developed zero-velocity layer approach to use for comparison. For both algorithms, we modeled the acoustic source as an approximate free-space Green’s function, not as a simple extrapolated spatial impulse. Tests on a synthetic data set modeled from rough topography and comparisons with the zero-velocity layer approach confirm the method’s effectiveness in imaging shallow and deep structures beneath rugged topography.
Pathologic Complete Response Rates in Young Women With BRCA1-Positive Breast Cancers After Neoadjuvant Chemotherapy
Authors: Byrski Tomasz , Gronwald Jacek , Huzarski Tomasz , Grzybowska Ewa , Budryk Magdalena , Stawicka Malgorzata , Mierzwa Tomasz , Szwiec Marek , Wiśniowski Rafal , Siolek Monika , Dent Rebecca , Lubinski Jan , Narod Steven
Published: December 2009

Purpose

To estimate the rate of pathologic complete response (pCR) to neoadjuvant chemotherapy in BRCA1 mutation carriers according to chemotherapy regimen.

Patients and Methods

From a registry of 6,903 patients, we identified 102 women who carried a BRCA1 founder mutation and who had been treated for breast cancer with neoadjuvant chemotherapy. Pathologic complete response was evaluated using standard criteria.

Results

Twenty-four (24%) of the 102 BRCA1 mutation carriers experienced a pCR. The response rate varied widely with treatment: a pCR was observed in one (7%) of 14 women treated with cyclophosphamide, methotrexate, and fluorouracil (CMF); in two (8%) of 25 women treated with doxorubicin and docetaxel (AT); in 11 (22%) of 51 women treated with doxorubicin and cyclophosphamide (AC) or fluorouracil, doxorubicin, and cyclophosphamide (FAC), and in 10 (83%) of 12 women treated with cisplatin.

Conclusion

A low rate of pCR was observed in women with breast cancer and a BRCA1 mutation who were treated with AT or CMF. A high rate of pCR was seen after treatment with cisplatin. An intermediate rate of PCR was associated with AC or FAC. The relative benefits of AC and platinum therapy need to be confirmed through follow-up of this and other cohorts.
Prognostic Role of KRAS and BRAF in Stage II and III Resected Colon Cancer: Results of the Translational Study on the PETACC-3, EORTC 40993, SAKK 60-00 Trial
Authors: Roth Arnaud D. , Tejpar Sabine , Delorenzi Mauro , Yan Pu , Fiocca Roberto , Klingbiel Dirk , Dietrich Daniel , Biesmans Bart , Bodoky György , Barone Carlo , Aranda Enrique , Nordlinger Bernard , Cisar Laura , Labianca Roberto , Cunningham David , Van Cutsem Eric , Bosman Fred
Published: December 2009

Purpose

Mutations within the KRAS proto-oncogene have predictive value but are of uncertain prognostic value in the treatment of advanced colorectal cancer. We took advantage of PETACC-3, an adjuvant trial with 3,278 patients with stage II to III colon cancer, to evaluate the prognostic value of KRAS and BRAF tumor mutation status in this setting.

Patients and Methods

Formalin-fixed paraffin-embedded tissue blocks (n = 1,564) were prospectively collected and DNA was extracted from tissue sections from 1,404 cases. Planned analysis of KRAS exon 2 and BRAF exon 15 mutations was performed by allele-specific real-time polymerase chain reaction. Survival analyses were based on univariate and multivariate proportional hazard regression models.

Results

KRAS and BRAF tumor mutation rates were 37.0% and 7.9%, respectively, and were not significantly different according to tumor stage. In a multivariate analysis containing stage, tumor site, nodal status, sex, age, grade, and microsatellite instability (MSI) status, KRAS mutation was associated with grade (P = .0016), while BRAF mutation was significantly associated with female sex (P = .017), and highly significantly associated with right-sided tumors, older age, high grade, and MSI-high tumors (all P < 10−4). In univariate and multivariate analysis, KRAS mutations did not have a major prognostic value regarding relapse-free survival (RFS) or overall survival (OS). BRAF mutation was not prognostic for RFS, but was for OS, particularly in patients with MSI-low (MSI-L) and stable (MSI-S) tumors (hazard ratio, 2.2; 95% CI, 1.4 to 3.4; P = .0003).

Conclusion

In stage II-III colon cancer, the KRAS mutation status does not have major prognostic value. BRAF is prognostic for OS in MS-L/S tumors.
Provision of Spiritual Care to Patients With Advanced Cancer: Associations With Medical Care and Quality of Life Near Death
Authors: Balboni Tracy Anne , Paulk Mary Elizabeth , Balboni Michael J. , Phelps Andrea C. , Loggers Elizabeth Trice , Wright Alexi A. , Block Susan D. , Lewis Eldrin F. , Peteet John R. , Prigerson Holly Gwen
Published: December 2009

Purpose

To determine whether spiritual care from the medical team impacts medical care received and quality of life (QoL) at the end of life (EoL) and to examine these relationships according to patient religious coping.

Patients and Methods

Prospective, multisite study of patients with advanced cancer from September 2002 through August 2008. We interviewed 343 patients at baseline and observed them (median, 116 days) until death. Spiritual care was defined by patient-rated support of spiritual needs by the medical team and receipt of pastoral care services. The Brief Religious Coping Scale (RCOPE) assessed positive religious coping. EoL outcomes included patient QoL and receipt of hospice and any aggressive care (eg, resuscitation). Analyses were adjusted for potential confounders and repeated according to median-split religious coping.

Results

Patients whose spiritual needs were largely or completely supported by the medical team received more hospice care in comparison with those not supported (adjusted odds ratio [AOR] = 3.53; 95% CI, 1.53 to 8.12, P = .003). High religious coping patients whose spiritual needs were largely or completely supported were more likely to receive hospice (AOR = 4.93; 95% CI, 1.64 to 14.80; P = .004) and less likely to receive aggressive care (AOR = 0.18; 95% CI, 0.04 to 0.79; P = .02) in comparison with those not supported. Spiritual support from the medical team and pastoral care visits were associated with higher QOL scores near death (20.0 [95% CI, 18.9 to 21.1] v 17.3 [95% CI, 15.9 to 18.8], P = .007; and 20.4 [95% CI, 19.2 to 21.1] v 17.7 [95% CI, 16.5 to 18.9], P = .003, respectively).

Conclusion

Support of terminally ill patients' spiritual needs by the medical team is associated with greater hospice utilization and, among high religious copers, less aggressive care at EoL. Spiritual care is associated with better patient QoL near death.
Nilotinib As Front-Line Treatment for Patients With Chronic Myeloid Leukemia in Early Chronic Phase
Authors: Cortes Jorge E. , Jones Dan , O'Brien Susan , Jabbour Elias , Konopleva Marina , Ferrajoli Alessandra , Kadia Tapan , Borthakur Gautam , Stigliano Denise , Shan Jianqin , Kantarjian Hagop
Published: December 2009

Purpose

Although most patients with chronic myeloid leukemia (CML) in chronic phase respond well to front-line therapy with imatinib, some patients do not achieve the desirable end point, and others may eventually lose response or are intolerant.

Patients and Methods

Patients with newly diagnosed CML in chronic phase were treated with nilotinib 400 mg twice daily on an empty stomach as initial therapy.

Results

Among 51 patients in chronic phase observed for at least 3 months, 50 (98%) achieved a complete cytogenetic remission (CCyR), and 39 (76%) achieved a major molecular response (MMR). Responses occurred rapidly, with 96% of patients achieving CCyR by 3 months and 98% achieving CCyR by 6 months. The projected event-free survival at 24 months is 90%, and all patients are alive after a median follow-up time of 17 months. Grade ≥ 3 neutropenia occurred in 12% of patients, and thrombocytopenia in occurred 11%. Nonhematologic toxicity was usually grade 1 to 2 and manageable. The actual median dose at 12 months was 800 mg (range, 200 to 800 mg).

Conclusion

Nilotinib is an effective option for the initial management of CML in early chronic phase, producing high rates of CCyR and MMR, with most patients reaching these responses early during their therapy.
Investigation of the potential for vascular bubble formation in a repetitively diving dolphin
Authors: Houser D. S. , Dankiewicz-Talmadge L. A. , Stockard T. K. , Ponganis P. J.
Published: December 2009

The production of venous gas emboli (VGE) resulting from altered dive behavior is postulated as contributing to the stranding of beaked whales exposed to mid-frequency active sonar. To test whether nitrogen gas uptake during repetitive breath-hold diving is sufficient for asymptomatic VGE formation in odontocetes, a bottlenose dolphin (Tursiops truncatus Montagu) was trained to perform 10–12 serial dives with 60 s surface intervals to depths of 30, 50, 70 or 100 m. The dolphin remained at the bottom depth for 90 s on each dive. Doppler and/or two-dimensional imaging ultrasound did not detect VGE in the portal and brachiocephalic veins following a dive series. Van Slyke analyses of serial, post-dive blood samples drawn from the fluke yielded blood nitrogen partial pressure (PN2) values that were negligibly different from control samples. Mean heart rate (HR; ±1 s.d.) recorded during diving was 50±3 beats min–1 and was not significantly different between the 50, 70 and 100 m dive sessions. The absence of VGE and elevated blood PN2 during post-dive periods do not support the hypothesis that N2 supersaturation during repetitive dives contributes to VGE formation in the dolphin. The diving HR pattern and the presumed rapid N2 washout during the surface-interval tachycardia probably minimized N2 accumulation in the blood during dive sessions.
Fibre type-specific expression patterns of myosin heavy chain genes in adult torafugu Takifugu rubripes muscles
Authors: Akolkar D. B. , Kinoshita S. , Yasmin L. , Ono Y. , Ikeda D. , Yamaguchi H. , Nakaya M. , Erdogan O. , Watabe S.
Published: December 2009

Comprehensive in silico studies, based on the total fugu genome database, which was the first to appear in fish, revealed that torafugu Takifugu rubripes contains 20 sarcomeric myosin heavy chain (MYH) genes (MYH genes) (Ikeda et al., 2007). The present study was undertaken to identify MYH genes that would be expressed in adult muscles. In total, seven MYH genes were found by screening cDNA clone libraries constructed from fast, slow and cardiac muscles. Three MYH genes, fast-type MYHM86-1, slow-type MYHM8248 and slow/cardiac-type MYHM880, were cloned exclusively from fast, slow and cardiac muscles, respectively. Northern blot hybridization substantiated their specific expression, with the exception of MYHM880. In contrast, transcripts of fast-type MYHM2528-1 and MYHM1034 were found in both fast and slow muscles as revealed by cDNA clone library and northern blot techniques. This result was supported by in situ hybridization analysis using specific RNA probes, where transcripts of fast-type MYHM2528-1 were expressed in fast fibres with small diameters as well as in fibres of superficial slow muscle with large diameters adjacent to fast muscle. Transcripts of fast-type MYHM86-1 were expressed in all fast fibres with different diameters, whereas transcripts of slow-type MYHM8248 were restricted to fibres with small diameters located in a superficial part of slow muscle. Interestingly, histochemical analyses showed that fast fibres with small diameters and slow fibres with large diameters both contained acid-stable myofibrillar ATPase, suggesting that these fibres have similar functions, possibly in the generation of muscle fibres irrespective of their fibre types.
Gravikinesis inStylonychia mytilusis based on membrane potential changes
Authors: Krause Martin , Bräucker Richard , Hemmersbach Ruth
Published: December 2009

The graviperception of the hypotrichous ciliate Stylonychia mytilus was investigated using electrophysiological methods and behavioural analysis. It is shown that Stylonychia can sense gravity and thereby compensates sedimentation rate by a negative gravikinesis. The graviresponse consists of a velocity-regulating physiological component (negative gravikinesis) and an additional orientational component. The latter is largely based on a physical mechanism but might, in addition, be affected by the frequency of ciliary reversals, which is under physiological control. We show that the external stimulus of gravity is transformed to a physiological signal, activating mechanosensitive calcium and potassium channels. Earlier electrophysiological experiments revealed that these ion channels are distributed in the manner of two opposing gradients over the surface membrane. Here, we show, for the first time, records of gravireceptor potentials in Stylonychia that are presumably based on this two-gradient system of ion channels. The gravireceptor potentials had maximum amplitudes of approximately 4 mV and slow activation characteristics (0.03 mV s–1). The presumptive number of involved graviperceptive ion channels was calculated and correlates with the analysis of the locomotive behaviour.
Lateral line diversity among ecologically divergent threespine stickleback populations
Authors: Wark A. R. , Peichel C. L.
Published: December 2009

The lateral line is a mechanoreceptive sensory system that allows fish to sense objects and motion in their local environment. Variation in lateral line morphology may allow fish in different habitats to differentially sense and respond to salient cues. Threespine sticklebacks (Gasterosteus aculeatus) occupy a diverse range of aquatic habitats; we therefore hypothesized that populations within the G. aculeatus species complex might show variation in the morphology of the lateral line sensory system. We sampled 16 threespine stickleback populations from marine, stream and lake (including benthic and limnetic) habitats and examined the distribution, type and number of neuromasts on different regions of the body. We found that the threespine stickleback has a reduced lateral line canal system, completely lacking canal neuromasts. Although the arrangement of lines of superficial neuromasts on the body was largely the same in all populations, the number of neuromasts within these lines varied across individuals, populations and habitats. In pairwise comparisons between threespine sticklebacks adapted to divergent habitats, we found significant differences in neuromast number. Stream residents had more neuromasts than marine sticklebacks living downstream in the same watershed. In two independent lakes, benthic sticklebacks had more trunk neuromasts than sympatric limnetic sticklebacks, providing evidence for parallel evolution of the lateral line system. Our data provide the first demonstration that the lateral line sensory system can vary significantly between individuals and among populations within a single species, and suggest that this sensory system may experience different selection regimes in alternative habitats.
In-line motion causes high thrust and efficiency in flapping foils that use power downstroke
Authors: Licht S. C. , Wibawa M. S. , Hover F. S. , Triantafyllou M. S.
Published: December 2009

We show experimentally that flapping foil kinematics consisting of a power downstroke and a feathering upstroke together with a properly timed in-line motion, similar to those employed in forelimb propulsion of sea turtles, can produce high thrust and be hydrodynamically as efficient as symmetrically flapping foils. The crucial parameter for such asymmetrically flapping foils is a properly sized and timed in-line motion, whose effect is quantified by a new parameter, the advance angle, defined as the angle of the foil trajectory with respect to the horizontal, evaluated at the middle of the power downstroke. We show, in particular, that optimal efficiency in high aspect ratio rigid foils, accompanied by significant thrust production, is obtained for Strouhal numbers in the range 0.2–0.6 for Reynolds number equal to 13,000, and for values of the advance angle around 0.55π (100 deg.). The optimized kinematics consist of the foil moving back axially during the downstroke, in the direction of the oncoming flow, and rotating with a large pitch angle. This causes the force vector to rotate and become nearly parallel to the steady flow, thus providing a large thrust and a smaller transverse force. During the upstroke, the foil is feathering while it moves axially forward, i.e. away from the vorticity shed during the power stroke; as a result, the transverse force remains relatively small and no large drag force is produced. Observations from turtles confirm qualitatively the findings from the foil experiments.
Heart rate as a predictor of energy expenditure in undisturbed fasting and incubating penguins
Authors: Groscolas R. , Viera V. , Guerin N. , Handrich Y. , Côté S. D.
Published: December 2009

Heart rate (fH) measurement offers the possibility to monitor energy expenditure (EE) in wild animals if the EE/fH relationship for the species, physiological stages and activities of interest is known. This relationship has been extensively studied using oxygen consumption rate () measurement in captive, repeatedly handled king penguins (Aptenodytes patagonicus). Unfortunately, the potential effects of stress on the observed relationships resulting from handling and confinement were not considered. This study is the first involving undisturbed animals, and determines the EE/fH relationship in naturally fasting and freely incubating or captivity-acclimatized male and female king penguins. EE determination was based on (1) the measurement of body mass loss during periods of phase II fasting, and (2) the calculation of its energy equivalent from changes in body composition, i.e. 23.9 kJ g–1. fH levels in freely incubating and captivity-acclimatized birds were found to be 50–70% lower than those previously reported for resting king penguins during measurements. Significant EE/fH relationships were found in freely incubating and captive males and females (R2=0.59 to 0.84), with no difference observed between genders. The best overall relationship was obtained by including fasting duration (t, days) in the model: EE=818+43.7×fH+36.3t–1.4t×fH (R2=0.91). This equation yielded EE estimates approximately 26% higher than the previously reported ‘best’ predictive equation in king penguins, and even more so when fH was low. This result suggests that stress induces a disproportionate increase of fHvs O2 consumption, and that the use of EE/fH relationships obtained in stressed birds could lead to underestimated EE values.
The distinction between retractor and protractor muscles of the freshwater snail's male organ has no physiological basis
Authors: de Boer P. A. C. M. , Jansen R. F. , ter Maat A. , van Straalen N. M. , Koene J. M.
Published: December 2009

Many animals are equipped with organs that can be everted, a notable example being male copulatory organs. The ability to protrude or evert an organ generally requires protractor and retractor muscles. Male copulatory behaviour of the pond snail Lymnaea stagnalis (L.) involves eversion (protraction) and retraction of the relatively large penis-carrying organ. For this preputium, protractor and retractor muscle bands have been defined, which implies eversion and retraction through the activity of these muscle bands. However, no physiological data are available that confirm that the terms protractor and retractor are appropriate. To test whether eversion and retraction are possible without protractor and/or retractor muscle bands, lesion experiments were performed. The results show that with either one or several muscle bands lesioned, snails were still capable of everting their preputium and using it for copulation. However, the majority of animals that had six or more muscle bands lesioned were unable to retract its preputium. Hence, retractor muscle bands serve their designated function whereas protractor muscle bands do not. We therefore suggest that a different terminology is used in which all muscle bands are retractors and, based on their location, are either called distal or proximal retractors. The findings furthermore indicate that the preputium muscle bands are normally contracted, possibly in a catch state, retaining the organ inside without high-energy expenditure.
Molt cycle regulation of protein synthesis in skeletal muscle of the blackback land crab, Gecarcinus lateralis, and the differential expression of a myostatin-like factor during atrophy induced by molting or unweighting
Authors: Covi J. A. , Bader B. D. , Chang E. S. , Mykles D. L.
Published: December 2009

In decapod crustaceans, claw muscle undergoes atrophy in response to elevated ecdysteroids while thoracic muscle undergoes atrophy in response to unweighting. The signaling pathways that regulate muscle atrophy in crustaceans are largely unknown. Myostatin is a negative regulator of muscle growth in mammals, and a myostatin-like cDNA is preferentially expressed in muscle of the land crab, Gecarcinus lateralis (Gl-Mstn). Contrary to prediction, levels of Gl-Mstn mRNA decreased dramatically in both the claw closer and weighted thoracic muscles when molting was induced by either eyestalk ablation (ESA) or multiple limb autotomy (MLA). However, the effect of molt induction was greater in the claw muscle. By late premolt, Gl-Mstn mRNA in the claw muscle decreased 81% and 94% in ESA and MLA animals, respectively, and was negatively correlated with ecdysteroids. Gl-Mstn mRNA in thoracic muscle decreased 68% and 82% in ESA and MLA animals, respectively, but was only weakly correlated with ecdysteroid. Claw and thoracic muscles also differed to varying extents in the expression of ecdysteroid receptor (Gl-EcR and Gl-RXR), elongation factor-2 (Gl-EF-2), and calpain T (Gl-CalpT) in response to molt induction, but levels of the four transcripts were not correlated with ecdysteroid. The downregulation of Gl-Mstn expression in premolt claw muscle coincided with 11- and 13-fold increases in protein synthesis in the myofibrillar and soluble protein fractions, respectively. Furthermore, the rate of the increase in the synthesis of soluble proteins was greater than that of myofibrillar proteins during early premolt (1.4:1, soluble:myofibrillar), but the two were equivalent during late premolt. By contrast, Gl-Mstn mRNA increased 3-fold and Gl-CalpT mRNA decreased 40% in unweighted thoracic muscle; there was little or no effect on Gl-EF-2, Gl-EcR, and Gl-RXR mRNA levels. These data indicate that Gl-Mstn expression is negatively regulated by both ecdysteroids and load-bearing contractile activity. The downregulation of Gl-Mstn in claw muscle may induce the elevated protein turnover associated with remodeling of the contractile apparatus during molt-induced atrophy. The upregulation of Gl-Mstn in unweighted thoracic muscle suggests that this factor is also involved in disuse atrophy when hemolymph ecdysteroid levels are low.
Ecophysiological response of Adélie penguins facing an experimental increase in breeding constraints
Authors: Beaulieu M. , Spée M. , Lazin D. , Ropert-Coudert Y. , le Maho Y. , Ancel A. , Raclot T.
Published: December 2009

Foraging strategies play a key role in breeding effort. Little is known, however, about their connection with hormonal and nutritional states, especially when breeding constraints vary. Here, we experimentally increased foraging costs and thus breeding constraints by handicapping Adélie penguins (Pygoscelis adeliae) with dummy devices representing 3–4% of the penguins' cross-sectional area. We examined food-related stress (via plasma corticosterone concentration) and nutritional state (via metabolite levels). Concurrently, we investigated the use of ecological niches via the isotopic signature of red blood cells indicating the trophic position (δ15N) and the spatial distribution (δ13C) of penguins. Handicapped birds performed ∼70% longer foraging trips and lost ∼60% more body mass than controls and their partners. However, corticosterone levels and the nutritional state were unchanged. The isotopic signature revealed that males and females differed in their foraging behaviour: upper trophic levels contributed more in the males' diet, who foraged in more pelagic areas. Handicapped and partner birds adopted the same strategy at sea: a shift towards higher δ13C values suggested that they foraged in more coastal areas than controls. This change in foraging decisions may optimize feeding time by decreasing travelling time. This may partly compensate for the presumed lower foraging efficiency of handicapped birds and for the energetic debt of their partners who had to fast ∼70% longer on the nest. We propose that this flexible use of ecological niches may allow birds facing increased breeding constraints to avoid chronic stress and to minimize the impact on their body condition.
Regulation of sarcoendoplasmic reticulum Ca2+-ATPase (SERCA) in turtle muscle and liver during acute exposure to anoxia
Authors: Ramnanan C. J. , McMullen D. C. , Bielecki A. , Storey K. B.
Published: December 2009

The freshwater turtle Trachemys scripta elegans naturally tolerates extended periods of anoxia during winter hibernation at the bottom of ice-locked ponds. Survival in this anoxic state is facilitated by a profound depression of metabolic rate. As calcium levels are known to be elevated in anoxic turtles, and ion pumping is an ATP-expensive process, we proposed that activity of the sarcoendoplasmic reticulum Ca2+-ATPase (SERCA) would be reduced in muscle and liver of T. s. elegans during acute (up to 20 h) exposure to anoxia. SERCA activity decreased ∼30% in liver and ∼40% in muscle after 1 h anoxia exposure and was ∼50% lower after 20 h of anoxia exposure in both tissues, even though SERCA protein levels did not change. SERCA kinetic parameters (increased substrate Km values, increased Arrhenius activation energy) were indicative of a less active enzyme form under anoxic conditions. Interestingly, the less active SERCA in anoxic turtles featured greater stability than the enzyme from normoxic animals as determined by both kinetic analysis (effect of low pH and low temperatures on Km MgATP) and conformational resistance to urea denaturation. The quick time course of deactivation and the stable changes in kinetic parameters that resulted suggested that SERCA was regulated by a post-translational mechanism. In vitro experiments indicated that SERCA activity could be blunted by protein phosphorylation and enhanced by dephosphorylation in a tissue-specific manner.
Identification of a calcitonin-like diuretic hormone that functions as an intrinsic modulator of the American lobster,Homarus americanus, cardiac neuromuscular system
Authors: Christie A. E. , Stevens J. S. , Bowers M. R. , Chapline M. C. , Jensen D. A. , Schegg K. M. , Goldwaser J. , Kwiatkowski M. A. , Pleasant T. K. , Shoenfeld L. , Tempest L. K. , Williams C. R. , Wiwatpanit T. , Smith C. M. , Beale K. M. , Towle D. W. , Schooley D. A. , Dickinson P. S.
Published: December 2009

In insects, a family of peptides with sequence homology to the vertebrate calcitonins has been implicated in the control of diuresis, a process that includes mixing of the hemolymph. Here, we show that a member of the insect calcitonin-like diuretic hormone (CLDH) family is present in the American lobster, Homarus americanus, serving, at least in part, as a powerful modulator of cardiac output. Specifically, during an ongoing EST project, a transcript encoding a putative H. americanus CLDH precursor was identified; a full-length cDNA was subsequently cloned. In silico analyses of the deduced prepro-hormone predicted the mature structure of the encoded CLDH to be GLDLGLGRGFSGSQAAKHLMGLAAANFAGGPamide (Homam-CLDH), which is identical to a known Tribolium castaneum peptide. RT-PCR tissue profiling suggests that Homam-CLDH is broadly distributed within the lobster nervous system, including the cardiac ganglion (CG), which controls the movement of the neurogenic heart. RT-PCR analysis conducted on pacemaker neuron- and motor neuron-specific cDNAs suggests that the motor neurons are the source of the CLDH message in the CG. Perfusion of Homam-CLDH through the isolated lobster heart produced dose-dependent increases in both contraction frequency and amplitude and a dose-dependent decrease in contraction duration, with threshold concentrations for all parameters in the range 10–11 to 10–10 mol l–1 or less, among the lowest for any peptide on this system. This report is the first documentation of a decapod CLDH, the first demonstration of CLDH bioactivity outside the Insecta, and the first detection of an intrinsic neuropeptide transcript in the crustacean CG.
First evidence of fine colour discrimination ability in ants (Hymenoptera, Formicidae)
Authors: Camlitepe Y. , Aksoy V.
Published: December 2009

In the present study, we report the first evidence that ants discriminate and learn perceptually close colour stimuli. Foragers of the ant species Cataglyphis aenescens and Formica cunicularia were trained in a Y-maze choice apparatus to monochromatic light stimuli of a constant intensity associated with a food reward. Two stimuli, with a mean wavelength of 40 nm perceptual distance, were chosen from the UV (340 nm vs 380 nm) and the green (510 nm vs 550 nm) range because these species are UV–green dichromats. Foragers were trained with two conditioning paradigms [absolute conditioning (AC) and differential conditioning (DC)]. In the UV range, C. aenescens foragers failed to discriminate when presented with a small colour difference in both training procedures. Foragers also failed in the green range when trained with AC but showed significant bias towards the rewarded stimulus when trained with DC. Formica cunicularia foragers achieved the task in the UV range when trained with DC only. In the green range, F. cunicularia foragers showed clear preference for the rewarded stimulus in both training conditioning procedures. Foragers never failed in choosing the rewarded stimulus in DC even when the intensity of the rewarded stimulus was reduced by one log unit. This clearly indicates that DC is of paramount importance to discriminate perceptually close colour stimuli.
Selections that optimize RNA display in the yeast three-hybrid system
Authors: Wurster Susan E. , Maher L. James
Published: December 2009

The yeast three-hybrid system (Y3H) is a powerful tool to select or confirm RNA–protein interactions. Target protein recognition of an RNA insert within a test transcript depends on at least three factors: intrinsic protein affinity for the properly folded insert, retention of RNA insert tertiary structure within a longer RNA transcript, and accessibility of the RNA insert to the target protein. Y3H reporter gene readout reflects the combination of these factors. Here, we discuss RNA insert tertiary structure and accessibility in the Y3H as “RNA display.” We review evidence that RNA display can sometimes be optimized during Y3H selections that do not increase the intrinsic affinity of an RNA insert for a target protein. This situation is more likely when a library of RNA inserts and heterogeneous flanking sequences is subjected to selection, and is less likely when point mutations are targeted to the insert in a fixed context. An RNA display vector with enhanced modularity has been developed to minimize sequence context effects in the Y3H.
Perturbation of Numerical Confidential Data via Skew-t Distributions
Authors: Lee Seokho , Genton Marc G. , Arellano-Valle Reinaldo B.
Published: December 2009

We propose a new data perturbation method for numerical database security problems based on skew-t distributions. Unlike the normal distribution, the more general class of skew-t distributions is a flexible parametric multivariate family that can model skewness and heavy tails in the data. Because databases having a normal distribution are seldom encountered in practice, the newly proposed approach, coined the skew-t data perturbation (STDP) method, is of great interest for database managers. We also discuss how to preserve the sample mean vector and sample covariance matrix exactly for any data perturbation method. We investigate the performance of the STDP method by means of a Monte Carlo simulation study and compare it with other existing perturbation methods. Of particular importance is the ability of STDP to reproduce characteristics of the joint tails of the distribution in order for database users to answer higher-level questions. We apply the STDP method to a medical database related to breast cancer.
Securing the Containerized Supply Chain: Analysis of Government Incentives for Private Investment
Authors: Bakshi Nitin , Gans Noah
Published: December 2009

To mitigate the threat that terrorists smuggle weapons of mass destruction into the United States through maritime containers, the U.S. Bureau of Customs and Border Protection (CBP) inspects containers upon entry to domestic ports. Inspection-driven congestion is costly, and CBP provides incentives to firms to improve security upstream in the supply chain, thereby reducing the inspection burden at U.S. ports. We perform an economic analysis of this incentive program, called Customs-Trade Partnership Against Terrorism (C-TPAT), modeling in a game-theoretic framework the strategic interaction between CBP, trading firms, and terrorists. Our equilibrium results highlight the possibility that a properly run program can efficiently shift some of CBP's security burden to private industry. These results also suggest that CBP may have the opportunity to use strategic delay as an incentive for firms to join. Analysis of comparative statics shows that, with increasing capacity, membership in C-TPAT systematically declines.
An Analysis of Coordination Mechanisms for the U.S. Cash Supply Chain
Authors: Dawande Milind , Mehrotra Mili , Mookerjee Vijay , Sriskandarajah Chelliah
Published: December 2009

The overuse of its currency processing facilities by depository institutions (DIs) has motivated the Federal Reserve (Fed) to impose its new cash recirculation policy. This overuse is characterized by the practice of cross-shipping, where a DI both deposits and withdraws cash of the same denomination in the same business week in the same geographical area. Under the new policy, which came into effect July 2007, the Fed has imposed a recirculation fee on cross-shipped cash. The Fed intends to use this fee to induce DIs to effectively recirculate cash so that the societal cost of providing cash to the public is lowered. To examine the efficacy of this mechanism, we first characterize the social optimum and then analyze the response of DIs under a recirculation fee levied on cross-shipped cash. We show that neither a linear recirculation fee, which is the Fed's current practice, nor a more sophisticated nonlinear fee is sufficient to guarantee a socially optimal response from DIs. We then derive a fundamentally different mechanism that induces DIs to self-select the social optimum. Our mechanism incorporates a fairness adjustment that avoids penalizing DIs that recirculate their fair share of cash and rewards DIs that recirculate more than this amount. We demonstrate that the mechanism is easy to implement and tolerates a reasonable amount of imprecision in the problem parameters. We also discuss a concept of welfare-preserving redistribution wherein the Fed allows a group of DIs to reallocate (amongst themselves) their deposits and demand if such a possibility does not increase societal cost. Finally, we analyze the impact of incorporating the custodial inventory program, another component of the Fed's new policy.
Inquiring into Nostos and Its Cognates
Authors: Bonifazi Anna
Published: December 2009

Nostos is first considered as a poetic genre. In the epic tradition and within the Homeric poems, it typically designates the song about the sea travels of Greek heroes home from Troy. The identification of some extra-Homeric narrative motifs leads the author to explore the uses of nostos and of etymologically related words (such as nostimos, nosteō , and neomai ). The textual analysis highlights homeward as well as non-homeward, sea-oriented and non-sea-oriented meanings. The underlying concept is that of "surviving lethal dangers." Evidence of the semantic range in question comes from Homer as well as from other poetic texts.
A Curious Concoction: Tradition and Innovation in Olympiodorus' "Orphic" Creation of Mankind
Authors: Edmonds Radcliffe G.
Published: December 2009

Olympiodorus' Commentary on Plato's Phaedo I.3-6 has been the linchpin of the reconstructions of the supposed Orphic doctrine of original sin. While Olympiodorus links the Titans' dismemberment of Dionysus and anthropogony, he does not include any element of inherited guilt, either in his narration of the myth or in his interpretation. Moreover, his telling of the myth, which makes the anthropogony the sequel to the dismemberment of Dionysus, is an innovation made for the purposes of his own argument. Rather than preserving in fossilized form a sacred myth more than a millennium old, Olympiodorus concocts an innovative tale of his own.
Epic from Epigram: The Poetics of Valerius Flaccus' Argonautica
Authors: Dinter Martin T.
Published: December 2009

This article makes the case for the importance of epigram, in terms of both form and content, for Valerius Flaccus' Argonautica . In the battle scenes of Books 3 and 6, in particular, recurrent allusions to epigrammatic themes unveil Valerius' poetics of epigram that evoke the dead for poetic purposes. As part of this, the apostrophe te quoque serves as an epitaphic gesture that marks the Argonautica , with its recurrent civil war imagery, as an epitaph on the golden age. In addition, Valerius employs these epitaphic markers as an organising device, a narrative "glue" that makes the Iliadic and the Odyssean parts of his narrative hang together.
Plagiarism and Poetic Identity in Martial
Authors: Seo J. Mira
Published: December 2009

This article addresses the significance of plagiarism as a poetic theme in Martial's Epigrams . Martial is the first classical poet to use the term plagiarius to refer to literary theft ( Ep. 1.52), and elsewhere in his epigrams, he frequently accuses other poets of appropriating or copying his work. This article argues that Martial's explicit references to plagiarism illustrate a poetic self-identity invested in the materiality of his texts: as Martial objectifies his books, he also commodifies them as articles of the marketplace. By defining his poetry as material commodities available for purchase or theft, Martial also exposes the economic fictions of Roman literary patronage.
Performative Space and Garden Transgressions in Tacitus' Death of Messalina
Authors: von Stackelberg Katharine T.
Published: December 2009

This article considers the role of gardens in Tacitus Annales Book11 as performative and transgressive space. Tacitus' account posits garden space as a nexus of narrative uncertainty between historia and fabula . This relationship is considered in the context of the transformative potential of performative space and concludes that the narrative interaction between gardens, transgression, and transformation both reference and foreshadow Julio-Claudian mythic enactments and the politics of performance.
A Conversation between Annette Baier and Anik Waldow about Hume's Account of Sympathy
Authors: Baier Annette C. , Waldow Anik
Published: December 2009

We discuss the variety of sorts of sympathy Hume recognizes, the extent to which he thinks our sympathy with others' feelings depends on inferences from the other's expression, and from her perceived situation, and consider also whether he later changed his views about the nature and role of sympathy, in particular its role in morals.
Politeness, Paris and the Treatise
Authors: Tolonen Mikko
Published: December 2009

This article analyses Hume's notion of politeness as developed in a letter he wrote in Paris in 1734 and the account of the corresponding artificial virtue in the Treatise . The analysis will help us understand Hume's admiration for French manners and why politeness is presented as one of the central artificial virtues in the Treatise . Before the Treatise , Hume had already sided with Bernard Mandeville's theoretical outlook which stood in contrast to the popular eighteenth-century understanding of politeness as a natural quality of human nature. In the Treatise , Hume developed these notions about the artificial nature of politeness into one of the cornerstones of his account of human sociability.
The Miseries of Life: Hume and the Problem of Evil
Authors: Pitson Tony
Published: December 2009

My topic is Hume's treatment of the problem of evil in the Dialogues and elsewhere in his philosophical writings. The aim is to provide an overall view of Hume's position which also takes account of the historical debate associated with the problem of evil. Critical and interpretative issues will also be addressed. We shall see that Hume is concerned mainly with a particular form of the evidential argument from evil which appears especially damaging to theistic belief in so far as it calls into question traditional views of the nature of God.
Natural Instinct, Perceptual Relativity, and Belief in the External World in Hume's Enquiry
Authors: Butler Annemarie
Published: December 2009

In part 1 of Enquiry 12, Hume presents a skeptical argument against belief in external existence. The argument involves a perceptual relativity argument that seems to conclude straightaway the double existence of objects and perceptions, where objects cause and resemble perceptions. In Treatise 1.4.2, Hume claimed that the belief in double existence arises from imaginative invention, not reasoning about perceptual relativity. I dissolve this tension by distinguishing the effects of natural instinct and showing that some of these effects supplement the Enquiry 's perceptual relativity argument. The Enquiry 's skeptical argument thus reveals the fundamental involvement of natural instinct in any belief in external existence.
Reason in Hume's Passions
Authors: Brett Nathan , Paxman Katharina
Published: December 2009

Hume is famous for the view that "reason is, and ought only to be, the slave of the passions." His claim that "we are no sooner acquainted with the impossibility of satisfying any desire, than the desire itself vanishes" is less well known. Each seems, in opposite ways, shocking to common sense. This paper explores the latter claim, looking for its source in Hume's account of the passions and exploring its compatibility with his associationist psychology. We are led to the conclusion that this view—that desires vanish when fulfilment is deemed impossible—endows reason with a power over the passions that is at odds with its role as slave, and ultimately incompatible with a proper understanding of emotions such as grief. Such emotions involve continuing to want what one believes to be impossible. The human (and Humean) imagination can sustain desires without the belief that fulfilment is possible.
Hume and the Prince of Thieves
Authors: Welchman Jennifer
Published: December 2009

Hume's readers love to hate the Sensible Knave. But hating the Knave is like hating a messenger with bad tidings. The message is that there is a gap, on Hume's account, between our motivations and our obligations to just action. But it isn't the Knave's character that is to blame, for the same gap will be found if we turn our attention to alter egos, such as Robin Hood, the benevolent "Prince of Thieves." Replacing self-interest with benevolence not only does not make the gap go away, it makes it harder to bridge. Of the two, it is benevolence, not self-interest, that actually poses the more serous challenge to Hume's account of justice.