bluuebunny/crossref_metadata_2025 huggingface dataset:
Electron tomography of the microtubule cytoskeleton in multinucleated hyphae of Ashbya gossypii
Authors: Gibeaux Romain , Lang Claudia , Politi Antonio Z. , Jaspersen Sue L. , Philippsen Peter , Antony Claude
Published: September 2012

We report the mechanistic basis guiding the migration pattern of multiple nuclei in hyphae of Ashbya gossypii. Using electron tomography, we reconstructed the cytoplasmic microtubule (cMT) cytoskeleton in three tip regions with a total of 13 nuclei and also the spindle microtubules of four mitotic nuclei. Each spindle pole body (SPB) nucleates three cMTs and most cMTs above a certain length grow according to their plus-end structure. Long cMTs closely align for several microns along the cortex, presumably marking regions where dynein generates pulling forces on nuclei. Close proximity between cMTs emanating from adjacent nuclei was not observed. The majority of nuclei carry duplicated side-by-side SPBs, which together emanate an average of six cMTs, in most cases in opposite orientation with respect to the hyphal growth axis. Such cMT arrays explain why many nuclei undergo short-range back and forth movements. Only occasionally do all six cMTs orient in one direction, a precondition for long-range nuclear bypassing. Following mitosis, daughter nuclei carry a single SPB with three cMTs. The increased probability that all three cMTs orient in one direction explains the high rate of nuclear bypassing observed in these nuclei. The A. gossypii mitotic spindle was found to be structurally similar to that of Saccharomyces cerevisiae in terms of nuclear microtubule (nMT) number, length distribution and three-dimensional organization even though the two organisms differ significantly in chromosome number. Our results suggest that two nMTs attach to each kinetochore in A. gossypii and not only one nMT like in S. cerevisiae.
A flavonol present in cocoa [(−)epicatechin] enhances snail memory
Authors: Fruson Lee , Dalesman Sarah , Lukowiak Ken
Published: September 2012

Dietary consumption of flavonoids (plant phytochemicals) may improve memory and neuro-cognitive performance, though the mechanism is poorly understood. Previous work has assessed cognitive effects in vertebrates; here we assess the suitability of Lymnaea stagnalis as an invertebrate model to elucidate the effects of flavonoids on cognition. (−)Epicatechin (epi) is a flavonoid present in cocoa, green tea and red wine. We studied its effects on basic snail behaviours (aerial respiration and locomotion), long-term memory (LTM) formation and memory extinction of operantly conditioned aerial respiratory behaviour. We found no significant effect of epi exposure (15 mg l−1) on either locomotion or aerial respiration. However, when snails were operantly conditioned in epi for a single 0.5 h training session, which typically results in memory lasting ~3 h, they formed LTM lasting at least 24 h. Snails exposed to epi also showed significantly increased resistance to extinction, consistent with the hypothesis that epi induces a more persistent LTM. Thus training in epi facilitates LTM formation and results in a more persistent and stronger memory. Previous work has indicated that memory-enhancing stressors (predator kairomones and KCl) act via sensory input from the osphradium and are dependent on a serotonergic (5-HT) signalling pathway. Here we found that the effects of epi on LTM were independent of osphradial input and 5-HT, demonstrating that an alternative mechanism of memory enhancement exists in L. stagnalis. Our data are consistent with the notion that dietary sources of epi can improve cognitive abilities, and that L. stagnalis is a suitable model with which to elucidate neuronal mechanisms.
Backward flight in hummingbirds employs unique kinematic adjustments and entails low metabolic cost
Authors: Sapir Nir , Dudley Robert
Published: September 2012

Backward flight is a frequently used transient flight behavior among members of the species-rich hummingbird family (Trochilidae) when retreating from flowers, and is known from a variety of other avian and hexapod taxa, but the biomechanics of this intriguing locomotor mode have not been described. We measured rates of oxygen uptake () and flight kinematics of Anna's hummingbirds, Calypte anna (Lesson), within a wind tunnel using mask respirometry and high-speed videography, respectively, during backward, forward and hovering flight. We unexpectedly found that in sustained backward flight is similar to that in forward flight at equivalent airspeed, and is about 20% lower than hovering . For a bird that was measured throughout a range of backward airspeeds up to a speed of 4.5 m s−1, the power curve resembled that of forward flight at equivalent airspeeds. Backward flight was facilitated by steep body angles coupled with substantial head flexion, and was also characterized by a higher wingbeat frequency, a flat stroke plane angle relative to horizontal, a high stroke plane angle relative to the longitudinal body axis, a high ratio of maximum:minimum wing positional angle, and a high upstroke:downstroke duration ratio. Because of the convergent evolution of hummingbird and some hexapod flight styles, flying insects may employ similar kinematics while engaged in backward flight, for example during station keeping or load lifting. We propose that backward flight behavior in retreat from flowers, together with other anatomical, physiological, morphological and behavioral adaptations, enables hummingbirds to maintain strictly aerial nectarivory.
Exogenous versus Endogenous Separation
Authors: Fujita Shigeru , Ramey Garey
Published: September 2012

This paper assesses how various approaches to modeling the separation margin affect the quantitative ability of the Mortensen-Pissarides labor matching model. The model with a constant separation rate fails to produce realistic volatility and productivity responsiveness of the separation rate and worker flows. The specification with endogenous separation succeeds along these dimensions. Allowing for on-the-job search enables the model to replicate the Beveridge curve. All specifications, however, fail to generate sufficient volatility of the job finding rate. While adopting the Hagedorn-Manovskii calibration remedies this problem, the volume of job-to-job transitions in the on-the-job search specification becomes essentially zero. (JEL E24, J41, J64)
Measurement of transplanted pancreatic volume using computed tomography: reliability by intra- and inter-observer variability
Authors: Lundqvist Eva , Segelsjö Monica , Andersson Anna , Magnusson Anders , Biglarnia Ali-Reza
Published: September 2012

Background

Unlike other solid organ transplants, pancreas allografts can undergo a substantial decrease in baseline volume after transplantation. This phenomenon has not been well characterized, as there are insufficient data on reliable and reproducible volume assessments. We hypothesized that characterization of pancreatic volume by means of computed tomography (CT) could be a useful method for clinical follow-up in pancreas transplant patients.

Purpose

To evaluate the feasibility and reliability of pancreatic volume assessment using CT scan in transplanted patients.

Material and Methods

CT examinations were performed on 21 consecutive patients undergoing pancreas transplantation. Volume measurements were carried out by two observers tracing the pancreatic contours in all slices. The observers performed the measurements twice for each patient. Differences in volume measurement were used to evaluate intra- and inter-observer variability.

Results

The intra-observer variability for the pancreatic volume measurements of Observers 1 and 2 was found to be in almost perfect agreement, with an intraclass correlation coefficient (ICC) of 0.90 (0.77-0.96) and 0.99 (0.98-1.0), respectively. Regarding inter-observer validity, the ICCs for the first and second measurements were 0.90 (range, 0.77-0.96) and 0.95 (range, 0.85-0.98), respectively.

Conclusion

CT volumetry is a reliable and reproducible method for measurement of transplanted pancreatic volume.
Estimating the potential of tissue donation in Scotland
Authors: Galea G
Published: September 2012

The Scottish National Blood Transfusion Service became the preferred provider of tissues in 2000. At that time, the only tissues procured were heart valves and some tendons from multiorgan donors. These sources and the range of tissues were not enough to provide for the clinical needs of Scottish patients. A systematic review was undertaken using the International Classification of Disease codes to assess what the potential pool of tissue donors would be by region, hospital and hospital department. Such data would enable us to focus our limited resources to maximize the yield of tissues to meet clinical demand. The data from this study were validated by a case-note audit in one hospital in Edinburgh. It was shown that the maximum tissue donor potential of approximately 48.5 per million population was in the central belt of Scotland in hospitals with large emergency medicine departments.
Digital acrometastases as first sign of hepatocellular carcinoma
Authors: Rauf M S , Motta L , Connolly C
Published: September 2012

Digital acrometastases as a primary presentation of hepatocellular carcinoma (HCC) is rare. A 66-year-old man with no history of malignancy presented to the plastic surgery department with two skin lesions, one on the bridge of his nose and one on distal phalanx of left little finger. A working diagnosis of cutaneous metastases was made. Immediately prior to admission for excision of these lesions he was admitted with right upper quadrant pain and a jaundiced discolouration of the skin. The lesions were excised as planned and histopathological examination revealed metastatic HCC. A subsequent magnetic resonance imaging showed a lobulated mass consistent with primary HCC.
Non-stroke admissions to a hyperacute stroke unit
Authors: Reid J M , Currie Y , Baird T
Published: September 2012

A significant proportion of patients presenting to hyperacute stroke units (HSUs) are diagnosed with non-stroke (NS). This study aimed to assess the rate and diagnoses of NS patients admitted to a HSU and the implications for clinical service provision. Admissions to the HSU at the Southern General Hospital, Glasgow, were retrospectively assessed (March 2007–September 2007). NS patients were identified by two parallel ascertainment methods and NS diagnosis was confirmed by case-note and discharge letter review. Of 375 presentations, 116 (31%) were due to NS. NS diagnosis was more likely for local referrals than from regional hospitals (41% versus 19%; P = 0.0002). Compared with stroke/transient ischaemic attack patients, NS patients were significantly younger, more likely to have an magnetic resonance imaging (MRI) scan and had a shorter length of hospital stay. Common NS diagnoses were migraine (22%), functional neurological disorder (14%), syncope (12%) and seizure (6%). NS patients who had an MRI scan were more likely to have a length of stay ≥2 days (75% versus 53%; P = 0.03). NS makes up one-third of acute stroke-like presentations with a high frequency of neurological conditions. NS patients tend to be younger and require significant investigation. The increased use of MRI and neurological services has implications for providing a hyperacute stroke service.
Duration of l-dopa and dopamine agonist monotherapy in Parkinson's disease
Authors: Nissen T , Newman E J , Grosset Ka , Daghem M , Pal G , Stewart M , Odin P , Macphee G J , Grosset D G
Published: September 2012

The expected duration of initial antiparkinson monotherapy before the need for supplementation is not clearly defined for routine practice. The aim of this study was to define the length of l-dopa (L-3, 4-dihydrophenylalanine) and dopamine agonist monotherapy. The duration of monotherapy and discontinuation rates were investigated in a natural observational setting by plotting Kaplan–Meier survival curves. Out of 345 patients, 180 (52.2%) received l-dopa and 165 (47.8%) received a dopamine agonist as initial monotherapy. Half of the patients starting l-dopa received supplementary therapy within 3.6 years (95% confidence interval, 3.2-4.6), significantly longer than for dopamine agonist monotherapy (half required a second agent at 2.3 years [2.0-2.9]; P = 0.00017). Discontinuation of l-dopa therapy was 1%. Dopamine agonists were stopped (due to side-effects like impulse control disorders [6%], somnolence [4%] and light-headedness [3%]) in 20% over four years. The duration and tolerability of l-dopa and dopamine agonists as initial Parkinson's disease monotherapy are defined in this study; this may form part of the information exchange with patients.
Electrocardiographic enigma of a classical disease: pellagra
Authors: Kavitha B , Balasubramanian R , Kumar Thirumal
Published: September 2012

Pellagra is caused by a deficiency of niacin. It is endemic in Africa and Asia where the staple diet of the many refugees or displaced people is corn-based and, therefore, nicotinic acid–deficient. It is also frequently seen in developed countries among chronic alcoholics or, occasionally, those suffering from anorexia nervosa. The usual manifestations are diarrhoea, dementia and dermatitis (the 3Ds), which if left untreated may lead to death. Cardiac manifestations and electrocardiographic changes are rarely seen in those suffering from pellagra. We present a case of pellagra in an alcoholic who presented with the classical rash over the upper limbs along with electrocardiographic changes but without any cardiac symptoms, both of which resolved dramatically after he had been given niacin supplements.
Pricing and Hedging with Discontinuous Functions: Quasi–Monte Carlo Methods and Dimension Reduction
Authors: Wang Xiaoqun , Tan Ken Seng
Published: September 2012

Quasi–Monte Carlo (QMC) methods are important numerical tools in the pricing and hedging of complex financial instruments. The effectiveness of QMC methods crucially depends on the discontinuity and the dimension of the problem. This paper shows how the two fundamental limitations can be overcome in some cases. We first study how path-generation methods (PGMs) affect the structure of the discontinuities and what the effect of discontinuities is on the accuracy of QMC methods. The insight is that the discontinuities can be QMC friendly (i.e., aligned with the coordinate axes) or not, depending on the PGM. The PGMs that offer the best performance in QMC methods are those that make the discontinuities QMC friendly. The structure of discontinuities can affect the accuracy of QMC methods more significantly than the effective dimension. This insight motivates us to propose a novel way of handling the discontinuities. The basic idea is to align the discontinuities with the coordinate axes by a judicious design of a method for simulating the underlying processes. Numerical experiments demonstrate that the proposed method leads to dramatic variance reduction in QMC methods for pricing options and for estimating Greeks. It also reduces the effective dimension of the problem.

This paper was accepted by Assaf Zeevi, stochastic models and simulation.
Diagnostic Accuracy Under Congestion
Authors: Alizamir Saed , de Véricourt Francis , Sun Peng
Published: September 2012

In diagnostic services, agents typically need to weigh the benefit of running an additional test and improving the accuracy of diagnosis against the cost of delaying the provision of services to others. Our paper analyzes how to dynamically manage this accuracy/congestion trade-off. To that end, we study an elementary congested system facing an arriving stream of customers. The diagnostic process consists of a search problem in which the service provider conducts a sequence of imperfect tests to determine the customer's type. We find that the agent should continue to perform the diagnosis as long as her current belief that the customer is of a given type falls into an interval that depends on the congestion level as well as the number of performed tests thus far. This search interval should shrink as congestion intensifies and as the number of performed tests increases if additional conditions hold. Our study reveals that, contrary to diagnostic services without congestion, the base rate (i.e., the prior probability of the customer type) has an effect on the agent's search strategy. In particular, the optimal search interval shrinks when customer types are more ambiguous a priori, i.e., as the base rate approaches the value at which the agent is indifferent between types. Finally, because of congestion effects, the agent should sometimes diagnose the customer as being of a given type, even if test results indicate otherwise. All these insights disappear in the absence of congestion.

This paper was accepted by Martin Lariviere, operations management.
First-Party Content and Coordination in Two-Sided Markets
Authors: Hagiu Andrei , Spulber Daniel
Published: September 2012

The strategic use of first-party content by two-sided platforms is driven by two key factors: the nature of buyer and seller expectations (favorable versus unfavorable) and the nature of the relationship between first-party content and third-party content (complements or substitutes). Platforms facing unfavorable expectations face an additional constraint: their prices and first-party content investment need to be such that low (zero) participation equilibria are eliminated. This additional constraint typically leads them to invest more (less) in first-party content relative to platforms facing favorable expectations when first- and third-party content are substitutes (complements). These results hold with both simultaneous and sequential entry of the two sides. With two competing platforms—incumbent facing favorable expectations and entrant facing unfavorable expectations—and multi-homing on one side of the market, the incumbent always invests (weakly) more in first-party content relative to the case in which it is a monopolist.

This paper was accepted by Bruno Cassiman, business strategy.
Vertical Differentiation with Variety-Seeking Consumers
Authors: Zeithammer Robert , Thomadsen Raphael
Published: September 2012

We analyze price and quality competition in a vertically differentiated duopoly in which consumers have a preference for variety. The preference for variety is a consequence of diminishing marginal utility for repeated experiences with the same product. We find consumer variety seeking can either soften or intensify price competition, depending on the difference in firm qualities and the strength of consumer preference for variety. When the qualities are similar (or the consumer preference for variety is strong), prices and profits are higher than would be obtained in the absence of variety seeking. On the other hand, if qualities differ enough (or the preference for variety is weak), stronger preferences for variety are associated with more intense price competition and lower profits. When firms set their qualities before competing on price and the range of feasible qualities is restricted such that variety seeking softens competition, competing firms choose to minimally differentiate themselves from each other. The preference for variety can drive the firms to offer multiunit discounts, and the greater price flexibility from these discounts does not necessarily reduce profits relative to simple unit pricing.

This paper was accepted by J. Miguel Villas-Boas, marketing.
Competitive Incentives: Working Harder or Working Smarter?
Authors: Bracha Anat , Fershtman Chaim
Published: September 2012

Almost all jobs require a combination of cognitive effort and labor effort. This paper focuses on the effect that competitive incentive schemes have on the chosen combination of these two types of efforts. We use an experimental approach to show that competitive incentives may induce agents to work harder but not necessarily smarter. This effect was stronger for women.

This paper was accepted by John List, behavioral economics.
How Costly Is Diversity? Affirmative Action in Light of Gender Differences in Competitiveness
Authors: Niederle Muriel , Segal Carmit , Vesterlund Lise
Published: September 2012

Affirmative action is often criticized for causing reverse discrimination and lowering the qualifications of those hired under the policy. However, the magnitude of such adverse effects depends on whether the best suited candidate is hired absent the policy. Indeed affirmative action may compensate for the distortion discrimination imposes on the selection of candidates. This paper asks whether affirmative action can have a similar corrective impact when qualified individuals fail to apply for a job. We evaluate the effect of introducing a gender quota in an environment where high-performing women fail to enter competitions they can win. We show that guaranteeing women equal representation among winners increases their entry. The response exceeds that predicted by the change in probability of winning and is in part driven by women being more willing to compete against other women. The consequences are substantial as the boost in supply essentially eliminates the anticipated costs of the policy.

This paper was accepted by Uri Gneezy, behavioral economics.
Differences in long-term fixation between mobile-bearing and fixed-bearing knee prostheses at ten to 12 years’ follow-up
Authors: Pijls B. G. , Valstar E. R. , Kaptein B. L. , Nelissen R. G. H. H.
Published: September 2012

This single-blinded randomised controlled trial investigated whether one design of mobile-bearing (MB) total knee replacement (TKR) has any advantage over a fixed-bearing (FB) design on long-term fixation as measured by radiostereometry. The amount of wear underneath the mobile bearing was also evaluated. A series of 42 knees was randomised to MB or FB tibial components with appropriate polyethylene inserts and followed for between ten and 12 years, or until the death of the patient. The polyethylene in the MB group was superior in that it was gamma-irradiated in inert gas and was calcium-stearate free; the polyethylene in the FB group was gamma-irradiated in air and contained calcium stearate. In theory this should be advantageous to the wear rate of the MB group. At final follow-up the overall mean migration was 0.75 mm (sd 0.76) in the MB group and 0.66 mm (sd 0.4) in the FB group, with the FB group demonstrating more posterior tilt and the MB group more internal rotation. In the FB group there was one revision for aseptic loosening, but none in the MB group. There were no significant differences in clinical or radiological scores.

For the MB group, the mean linear wear rate on the under-surface was 0.026 mm/year (sd 0.014). This was significantly smaller than the wear rate of 0.11 mm/year (sd 0.06) in the MB between femur and polyethylene (p < 0.001). Nevertheless, even in a best-case setting the mobile bearings of this TKR design had no apparent advantage in terms of fixation over the FB knee prosthesis at ten to 12 years. The wear underneath the mobile bearing was small and is unlikely to be clinically relevant.
Does obesity influence clinical outcome at nine years following total knee replacement?
Authors: Collins R. A. , Walmsley P. J. , Amin A. K. , Brenkel I. J. , Clayton R. A. E.
Published: September 2012

A total of 445 consecutive primary total knee replacements (TKRs) were followed up prospectively at six and 18 months and three, six and nine years. Patients were divided into two groups: non-obese (body mass index (BMI) < 30 kg/m2) and obese (BMI ≥ 30 kg/m2). The obese group was subdivided into mildly obese (BMI 30 to 35 kg/m2) and highly obese (BMI ≥ 35 kg/m2) in order to determine the effects of increasing obesity on outcome. The clinical data analysed included the Knee Society score, peri-operative complications and implant survival. There was no difference in the overall complication rates or implant survival between the two groups.

Obesity appears to have a small but significant adverse effect on clinical outcome, with highly obese patients showing lower function scores than non-obese patients. However, significant improvements in outcome are sustained in all groups nine years after TKR. Given the substantial, sustainable relief of symptoms after TKR and the low peri-operative complication and revision rates in these two groups, we have found no reason to limit access to TKR in obese patients.
Risk factors associated with surgical site infection in 30 491 primary total hip replacements
Authors: Namba R. S. , Inacio M. C. S. , Paxton E. W.
Published: September 2012

We examined patient and surgical factors associated with deep surgical site infection (SSI) following total hip replacement (THR) in a large integrated healthcare system. A retrospective review of a cohort of primary THRs performed between 2001 and 2009 was conducted. Patient characteristics, surgical details, surgeon and hospital volumes, and SSIs were identified using the Kaiser Permanente Total Joint Replacement Registry (TJRR). Proportional-hazard regression models were used to assess risk factors for SSI. The study cohort consisted of 30 491 THRs, of which 17 474 (57%) were performed on women. The mean age of the patients in the whole series was 65.5 years (13 to 97; sd 11.8) and the mean body mass index was 29.3 kg/m2 (15 to 67; sd 5.9). The incidence of SSI was 0.51% (155 of 30 491). Patient factors associated with SSI included female gender, obesity, and American Society of Anesthesiologists (ASA) score ≥ 3. Age, diagnosis, diabetes and race were not associated with SSI. The only surgical factor associated with SSI was a bilateral procedure. Surgeon and hospital volumes, use of antibiotic-laden cement, fixation method, laminar flow, body exhaust suits, surgical approach and fellowship training were not associated with risk of SSI.

A comprehensive infection surveillance system, combined with a TJRR, identified patient and surgical factors associated with SSI. Obesity and chronic medical conditions should be addressed prior to THR. The finding of increased SSI risk with bilateral THR requires further investigation.
Spondylodiscitis in infancy
Authors: Tsirikos A. I. , Tome-Bermejo F.
Published: September 2012

An eight-week-old boy developed severe thoracic spondylodiscitis following pneumonia and septicaemia. A delay in diagnosis resulted in complete destruction of the T4 and T5 vertebral bodies and adjacent discs, with a paraspinal abscess extending into the mediastinum and epidural space. Antibiotic treatment controlled the infection and the abscess was aspirated. At the age of six months, he underwent posterior spinal fusion in situ to stabilise the spine and prevent progressive kyphosis. At the age of 13 months, repeat imaging showed lack of anterior vertebral body re-growth and he underwent anterior spinal fusion from T3 to T6 and augmentation of the posterior fusion. At the age of five years, he had no symptoms and radiographs showed bony fusion across the affected levels.

Spondylodiscitis should be included in the differential diagnosis of infants who present with severe illness and atypical symptoms. Delayed diagnosis can result in major spinal complications with a potentially fatal outcome.
Hepaticocholecystoenterostomy as an alternative to hepaticojejunostomy for biliary bypass
Authors: Gani J , Lewis K
Published: September 2012

INTRODUCTION

Hepaticojejunostomy is the standard biliary bypass technique for periampullary cancer when trial dissection reveals unresectable disease or endoscopic stent placement is not possible. This anastomosis can be technically demanding and potentially difficult. The simpler technique of hepaticocholecystoenterostomy (HCE) has only previously been reported in very limited numbers and without outcome data.

METHODS

All patients undergoing HCE for the management of periampullary cancer were identified from a prospectively maintained computerised database of a single surgeon and were reviewed retrospectively. The HCE technique achieves a biliary bypass by two anastomoses, using the gallbladder as a conduit. It involves an anastomosis of the infundibulum of the gallbladder to the common hepatic duct followed by a second anastomosis of the gallbladder fundus to the proximal small bowel.

RESULTS

From 1996 to 2010, 30 patients with pancreatic adenocarcinoma required a biliary bypass after a failed trial of Whipple procedure (80%) or failed endoscopic stenting (20%). There were 19 men and 11 women with a mean age of 64.5 years. The mean operative time for HCE alone was 92 minutes. The mean length of hospital stay was nine days. There was a single grade 2 complication (readmission with gastric emptying delay) and a single grade 3 complication (bile leak requiring reoperation). Thirty-day mortality was zero and the mean survival was 12 months (with one patient still alive at the time of writing). There were no readmissions with recurrent biliary obstruction or cholangitis. One patient had developed an incisional hernia by the 24 month follow-up appointment.

CONCLUSIONS

HCE in periampullary cancer is safe and effective in selected patients. It involves two simple anastomoses with good access rather than one more demanding anastomosis. Morbidity, patency and overall survival are comparable with contemporary published series of hepaticojejunostomy.
Subconvexity for twisted L -functions on GL(3)
Authors: Blomer Valentin
Published: September 2012

Let $q$ be a large prime and $\chi$ the quadratic character modulo $q$. Let $\phi$ be a self-dual cuspidal Hecke eigenform for ${\rm SL}(3, \Bbb{Z})$, and $f$ a Hecke-Maa{\ss} cusp form for $\Gamma_0(q) \subseteq {\rm SL}_2(\Bbb{Z})$. We consider the twisted $L$-functions $L(s, \phi \times f \times \chi)$ and $L(s, \phi \times \chi)$ on ${\rm GL}(3)\times {\rm GL}(2)$ and ${\rm GL}(3)$ with conductors $q^6$ and $q^3$, respectively. We prove the subconvexity bounds $$ L(1/2, \phi \times f \times \chi) \ll_{\phi, f, \varepsilon} q^{5/4+\varepsilon},\quad L(1/2+it, \phi \times \chi) \ll_{\phi, t, \varepsilon} q^{5/8+\varepsilon} $$ for any $\varepsilon > 0$.
On rigid analytic uniformizations of Jacobians of Shimura curves
Authors: Longo Matteo , Rotger Victor , Vigni Stefano
Published: September 2012

The main goal of this article is to give an explicit rigid analytic uniformization of the maximal toric quotient of the Jacobian of a Shimura curve over $\Bbb{Q}$ at a prime dividing exactly the level. This result can be viewed as complementary to the classical theorem of \v{C}erednik and Drinfeld which provides rigid analytic uniformizations at primes dividing the discriminant. As a corollary, we offer a proof of a conjecture formulated by M. Greenberg in his paper on Stark-Heegner points and quaternionic Shimura curves, thus making Greenberg's construction of local points on elliptic curves over $\Bbb{Q}$ unconditional.
Plücker forms and the theta map
Authors: Brivio Sonia , Verra Alessandro
Published: September 2012

Let ${\rm SU}_X(r,0)$ be the moduli space of semistable vector bundles of rank r and trivial determinant over a smooth, irreducible, complex projective curve $X$. The theta map $\theta_r: {\rm SU}_X(r,0) \rightarrow \Bbb{P}^N$ is the rational map defined by the ample generator of ${\rm Pic}{\rm SU}_X(r,0)$. The main result of the paper is that $\theta_r$ is generically injective if $g \gg r$ and $X$ is general. This partially answers the following conjecture proposed by Beauville: $\theta_r$ is generically injective if $X$ is not hyperelliptic. The proof relies on the study of the injectivity of the determinant map $d_E: {\wedge}^r H^0(E) \rightarrow H^0(\det E)$, for a vector bundle $E$ on $X$, and on the reconstruction of the Grassmannian $G(r,rm)$ from a natural multilinear form associated to it, defined in the paper as the Pl\"ucker form. The method applies to other moduli spaces of vector bundles on a projective variety $X$.
The construction of doubly periodic minimal surfaces via balance equations
Authors: Connor Peter , Weber Matthias
Published: September 2012

Using Traizet's regeneration method, we prove the existence of many new 3-dimensional families of embedded, doubly periodic minimal surfaces. All these families have a foliation of ${\Bbb R}^3$ by vertical planes as a limit. In the quotient, these limits can be realized conformally as noded Riemann surfaces, whose components are copies of $\Bbb{C}^*$ with finitely many nodes. We derive the balance equations for the location of the nodes and exhibit solutions that allow for surfaces of arbitrarily large genus and number of ends in the quotient.
Groupe de Brauer et points entiers de deux familles de surfaces cubiques affines
Authors: Colliot-Thélène Jean-Louis , Wittenberg Olivier
Published: September 2012

Soit~$a$ un entier non nul. Si~$a$ n'est pas de la forme $9n\pm 4$ pour un $n \in {\bf Z}$, il n'y a pas d'obstruction de Brauer-Manin \`a l'existence d'une solution de l'\'equation $x^3+y^3+z^3=a$ en entiers $x, y, z \in{\bf Z}$. D'autre part, il n'y a pas d'obstruction de Brauer-Manin \`a l'existence d'une solution de l'\'equation $x^3+y^3+2z^3=a$ en entiers $x, y, z \in {\bf Z}$.
Calabi-Yau domains in three manifolds
Authors: Martín Francisco , Meeks William H.
Published: September 2012

We prove that for every smooth compact Riemannian three-manifold
$\overline{W}$ with nonempty boundary, there exists a smooth properly
embedded one-manifold $\Delta \subset W={\rm Int}(\overline{W})$, each of
whose components is a simple closed curve and such that the domain
${\mathcal D} = W - \Delta$ does not admit any properly immersed open
surfaces with at least one annular end, bounded mean curvature, compact
boundary (possibly empty) and a complete induced Riemannian metric.
A Riemann singularity theorem for integral curves
Authors: Casalaina-Martin Sebastian , Kass Jesse Leo
Published: September 2012

We prove results generalizing the classical Riemann Singularity Theorem to the case of integral, singular curves. The main result is a computation of the multiplicity of the theta divisor of an integral, nodal curve at an arbitrary point. We also suggest a general formula for the multiplicity of the theta divisor of a singular, integral curve at a point and present some evidence that this formula should hold. Our results give a partial answer to a question posed by Lucia Caporaso in a recent paper.
Picard-Fuchs equations for relative periods and Abel-Jacobi map for Calabi-Yau hypersurfaces
Authors: Li Si , Lian Bong H. , Yau Shing-Tung
Published: September 2012

We study the variation of relative cohomology for a pair consisting of a smooth projective hypersurface and an algebraic subvariety in it. We construct an inhomogeneous Picard-Fuchs equation by applying a Picard-Fuchs operator to the holomorphic top form on a Calabi-Yau hypersurface in toric variety, and deriving a general formula for the $d$-exact form on one side of the equation. We also derive a double residue formula, giving a purely algebraic way to compute the inhomogeneous Picard-Fuchs equations for the Abel-Jacobi map, which has played an important role in the recent study of D-branes (by Morrison and Walcher). Using the variation formalism, we prove that the relative periods of toric B-branes on Calabi-Yau hypersurface satisfy the enhanced GKZ-hypergeometric system proposed in physics literature (by Alim, Hecht, Mayr, and Mertens), and discuss the relations between several works in the recent study of open string mirror symmetry. We also give the general solutions to the enhanced hypergeometric system.
The image of Galois representations attached to elliptic curves with an isogeny
Authors: Greenberg Ralph
Published: September 2012

We consider an elliptic curve $E$ defined over ${\bf Q}$ which has an isogeny of prime degree $p$ defined over ${\bf Q}$. Assuming that $E$ does not have complex multiplication and that $p > 7$, we show that the image of the Galois representation defined by the action of $G_{{\bf Q}}$ on the $p$-adic Tate module is as large as possible, given the existence of such an isogeny. Under a certain additional assumption, we also prove that result for $p = 7$. For $p = 5$, we show that the image is as large as allowed by the isogenies of $p$-power degree defined over ${\bf Q}$.
Nage Lizard Classification: Free-Listing and Other Evidence for a Covert Life-Form
Authors: Forth Gregory
Published: September 2012

Speakers of a Central-Malayo-Polynesian language, the Nage of Flores Island, Indonesia, name five folk generic categories of lizards. Ethnographic questioning and observed speech indicate that Nage additionally recognize a more inclusive, but unnamed, taxon glossable as ‘lizard’. Evidence for this taxon has further been generated by a modified form of free-listing. The article analyzes the results of this method, obtained from questioning seventy-two Nage speakers, and discusses the internal structure and taxonomic status of the general ‘lizard’ category. It is concluded that ‘lizard’ is a covert life-form taxon comprising distinctly prototypical and peripheral members and contrasting especially with the overt Nage life-form nipa ‘snake’.
Binomials and the Noun-to-Verb Ratio in Puma Rai Ritual Speech
Authors: Gaenszle Martin , Bickel Balthasar , Sharma Narayan P. , Pettigrew Judith , Rai Arjun , Rai Shree Kumar , Schackow Diana
Published: September 2012

This article examines the pairing of nouns in the type of parallelism known as binominals, expressions of paired words, in Puma Rai ritual speech. Using a large corpus of ritual and everyday language texts resulting from a language documentation project among the Puma Rai in Nepal, we explore the characteristics of ritual binomials and provide a quantitative analysis of noun-to-verb ratios in the two major ritual speech genres (shamanic and priestly invocations). It is argued that the increase of nouns in the ritual language under study leads to an inversion of the noun-to-verb ratio in relation to ordinary speech.
Verbal Classifiers in Innu
Authors: Drapeau Lynn , Lambert-Brétière Renée
Published: September 2012

This article reports on verbal classifier affixes in Innu (also known as Montagnais), an Algonquian language spoken in northeastern Quebec and Labrador, Canada. Verbal classifiers are normally characterized as a form of semantic agreement whereby an affix on the verb (the classifier) categorizes the shape or substance of the referent of an argument. The analysis of a corpus of natural speech data reveals that in a significant number of cases the classifier actually introduces a new semantic argument and is the sole reference to it in the clause or discourse. Such stand-alone classifiers refer to parts of a whole, identify the theme of an impersonal verb, or express a peripheral argument.
Diphthongs in Tohono O’odham
Authors: Miyashita Mizuki
Published: September 2012

This article examines the distribution of diphthongs in Tohono O’odham (Uto-Aztecan), dividing them into two types, light and heavy, on the basis of three characteristics: stress placement (a light diphthong occurs in either stressed or unstressed syllables while a heavy diphthong occurs in only stressed positions); reduplicative processes (a light diphthong undergoes segment-retention reduplication, and a heavy diphthong, segment-skipping reduplication); and restrictions on the phonemes allowed by each type (light diphthongs can contain [i], whereas heavy diphthongs do not). This analysis has implications for the treatment of Tohono O’odham diphthongs in terms of mora theory, for the status of the high front vowel, and for pedagogy.
African American Southerners and White Physicians: Medical Care at the Turn of the Twentieth Century
Authors: Pohl Lynn Marie
Published: September 2012

Much of what scholars know about race and medicine in the late-nineteenth-and early-twentieth-century South relates to the racial beliefs of white physicians and the segregated and exploitative treatment of black patients in hospitals and public health programs. This article shifts scholarly attention to the ways African American patients and their families took part in medical practice in commonplace settings of the home and office. The author examines how African Americans called upon local physicians in the rural and small-town South, how white physicians responded, and how they interacted in cases of serious illness, injury, and surgery. The claims of black southerners to physicians' treatments, in combination with small-town physicians' continuing reliance on interpersonal practices of medical care, made for an erratic but potentially distinctive cross-racial encounter—one involving a greater degree of negotiated authority and personal care than what generally has been recognized for this time and place.
Eugenics Visualized: The Exhibit of the Third International Congress of Eugenics, 1932
Authors: Stillwell Devon
Published: September 2012

This article investigates the exhibit of the Third International Congress of Eugenics, which was organized by Harry Hamilton Laughlin and showcased at the American Museum of Natural History in 1932. It argues that the exhibit's displays shaped popular eugenic ideology by connecting particular eugenic principles to specific visual representations that were experienced in relation to binaries such as the artistically traditional and the modern, the classical and the grotesque, and the scientific and the spectacle (or the "freak" and the medical specimen). These dichotomies were, in turn, experienced within the context of the exhibit's overall theme of eugenics as anchored in the past and the future and concern over the differential birthrate. The exhibit to the Third Congress provides insight into growing tensions within the eugenics movement of the 1930s, the importance of positive eugenics, the aesthetics of heredity, and how the "scientific truths" of a given era are publicized and perpetuated.
"Life in a Germ-Free World": Isolating Life from the Laboratory Animal to the Bubble Boy
Authors: Kirk Robert G. W.
Published: September 2012

This article examines a specific technology, the germ-free "isolator," tracing its development across three sites: (1) the laboratory for the production of standard laboratory animals, (2) agriculture for the efficient production of farm animals, and (3) the hospital for the control and prevention of cross-infection and the protection of individuals from infection. Germ-free technology traveled across the laboratory sciences, clinical and veterinary medicine, and industry, yet failed to become institutionalized outside the laboratory. That germ-free technology worked was not at issue. Working, however, was not enough. Examining the history of a technology that failed to find widespread application reveals the labor involved in aligning cultural, societal, and material factors necessary for successful medical innovation.
"Too Good to Be True": The Controversy over the Use of Permanganate of Potash as an Antidote to Snake Poison and the Circulation of Brazilian Physiology in the Nineteenth Century
Authors: Vimieiro Gomes Ana Carolina
Published: September 2012

This article examines an international controversy over the most visible scientific event of Brazilian physiology in the nineteenth century. In 1881, Brazilian scientist João Baptista Lacerda stated that he had found an efficient antidote to the poison of Brazilian snakes: permanganate of potash (nowadays, potassium permanganate). His findings were given great publicity in Brazil and traveled rapidly around the world. Scientists, especially in France, contradicted Lacerda's claims. They argued that permanganate of potash could not be a genuine antidote to snake bites since it could not neutralize snake venom when diffused in the body. Lacerda turned down such criticism, claiming that clinical observation provided solid evidence for the drug's local action, on the spot surrounding the bite. The controversy over the use of permanganate of potash as an antidote to snake bite illustrates different regimes of proof that could be mobilized in favor of a physiological discovery.
Media Heterotopia and Transnational Filmmaking: Mapping Real and Virtual Worlds
Authors: Chung Hye Jean
Published: September 2012

Focusing on The Fall (Tarsem Singh, 2006), The World (Zhangke Jia, 2004), and Avalon (Mamoru Oshii, 2001), this essay proposes a mode of heterotopic perception and analysis that recognizes the composited layers and material residues of globally dispersed production sites and laboring bodies in mediated transnational spaces.
A Country for Old Men: Unforgiven, The Shootist , and the Post-Heyday Western
Authors: Cloutier Jean-Christophe
Published: September 2012

This article introduces the concept of the post-heyday Western, a narrative mode featuring epic yet elderly protagonists. Focusing on Clint Eastwood's Unforgiven (1992), and Don Siegel's The Shootist (1976), it explores the old gunslinger's struggle to come to terms with the trauma of aging and his violent past.
Cranked Masculinity: Hypermediation in Digital Action Cinema
Authors: Palmer Lorrie
Published: September 2012

The mode of production and the visual aesthetic of the digital action cinema represented by Mark Neveldine and Brian Taylor's Crank (2006) and its 2009 sequel, Crank 2: High Voltage (both partially shot on Rollerblades at high speed), represent hypermediation as hypermasculinity. Reflecting the development of visual culture and a historically masculinized relationship with technology, the immersive gamespace created in this model of filmmaking indicates the narrational merging of product and process.
Fatal Attractions: "Place," the Korean War, and Gender in Niagara
Authors: Schleier Merrill
Published: September 2012

Niagara features a landscape or "place" as a star. Focusing especially on Niagara Falls' multilayered and traumatic history helps us understand the film's exploration of mental instability, eroticism, death, and even the ongoing Korean War. Yet the film's conventional plot structure is unable to resolve its gender, class, and other tensions, which reflect the fissures of midcentury America.
Television Crime Drama and Homeland Security: From Law & Order to "Terror TV"
Authors: Tasker Yvonne
Published: September 2012

This article explores the migration of themes of homeland security and political violence from sensational action formats to procedural crime dramas. It argues that, although the latter have typically developed distinctive strategies and relatively complex narratives, there are commonalities across the broad category of crime television. Themes explored include racial profiling, motive and political violence, coercion, and the ethics of interrogation within crime television.
The "Monumental" Heroine: Female Agency in Joseph Gaï Ramaka's Karmen Geï
Authors: Prabhu Anjali
Published: September 2012

Karmen Geï presents itself as a feminist African film with a scandalously revolutionary central character. These aspects of the film are reconsidered by focusing attention on the totality of its form, and by studying the politics of monumentalizing the heroine.
Belief and Introspective Knowledge in Treatise 1.3.7
Authors: Marušić Jennifer Smalligan
Published: September 2012

Hume argues that the difference between belief and mere conception consists in a difference in the manner of conception. His argument assumes that the difference between belief and mere conception must be a function of either the content conceived or of the manner of conception; however, it is unclear what justifies this assumption. I argue that the assumption depends on Hume’s confidence that we can know immediately that we believe when we believe, and that we can only have such knowledge of intrinsic features of our perceptions. I then claim that Hume’s argument against the view that the difference between belief and mere conception is a function of the content conceived faces a difficulty, because it relies on an apparently implausible view about mental representation. I propose an interpretation of the argument that avoids the difficulty and explains Hume’s puzzling claim that his account of belief answers “a new question unthought of by philosophers.”