bluuebunny/crossref_metadata_2025 huggingface dataset:
Earnings Benchmarks and the Information Content of Quarterly Foreign Earnings of U.S. Multinational Companies
Authors: Lacina Michael J. , Marks Barry R. , Shin Haeyoung
Published: March 2013

The meeting of earnings benchmarks is considered important for investors. The chief financial officers of U.S. companies state that the three most important earnings thresholds to meet are the earnings in the same quarter last year, the analysts' earnings forecast for the current quarter, and zero earnings. These earnings benchmarks have been defined in terms of total earnings. For U.S. multinational firms, total earnings consist primarily of domestic earnings and foreign earnings. We conduct an event study where we examine (1) the stock market reaction to meeting or beating quarterly domestic and foreign earnings benchmarks and (2) the market reaction to the changes in quarterly domestic and foreign earnings, while we control for meeting or beating the analysts' earnings forecast and the analysts' earnings forecast surprise. We find that the quarterly financial statement disclosure of domestic and foreign earnings under Statement of Financial Accounting Standards No. 131 supplies investors with valuable information that was not previously disseminated through financial analysts or other sources. The stock market reaction to meeting or beating foreign earnings from the same quarter in the prior year is stronger than the market reaction to meeting or beating domestic earnings from the same quarter in the prior year.
A Model of Tiered Settlement Networks
Authors: CHAPMAN JAMES , CHIU JONATHAN , MOLICO MIGUEL
Published: March 2013

Payment and settlement networks typically involve various tiers of intermediation. This paper develops a model of settlement system to study the endogenous structure of tiered settlement networks, and the welfare consequences of clearing agent (CA) failure. We offer two explanations for tiering: private information regarding participant’s credit worthiness and economies of scale in the participation in the settlement system. CAs play a monitoring and cost‐saving role in the settlement network. As a result, a failure of a CA can lead to a large and persistent welfare loss to the economy.
State Banks and the National Banking Acts: Measuring the Response to Increased Financial Regulation, 1860–1870
Authors: JAREMSKI MATTHEW
Published: March 2013

The National Banking Acts and their supporting legislation led to 263 state bank closures and 934 charter conversions between 1863 and 1870. This paper measures and analyzes these sudden changes using the period's first complete bank‐level census. The data suggest that the national capital requirements prevented many existing banks from converting to a national charter, whereas a tax on state bank notes was responsible for the large number of closures. The legislation also prevented new national banks from replacing closed state banks and, instead, encouraged note and security brokers to open new banks in developing areas along the Manufacturing Belt.
Gross Loan Flows
Authors: CRAIG BEN R. , HAUBRICH JOSEPH G.
Published: March 2013

Changes in net lending hide the much larger and more variable gross lending flows. We present a series of stylized facts about gross loan flows and how they vary over time, bank size, and the business cycle. We look at both the intensive (increases and decreases) and extensive (entry and exits) margins. In contrast to the standard result with net lending, gross lending quantities respond to monetary policy.
Anticipation of Future Consumption: A Monetary Perspective
Authors: FARIA JOÃO RICARDO , MCADAM PETER
Published: March 2013

We adapt the monetary model (Sidrauski 1967) to study the hypothesis of anticipation of future consumption. We assume that anticipation of future consumption affects an agent’s instantaneous utility and that all effects of future consumption on current well‐being are captured by the stock of future consumption. Monetary policy effectiveness is thereby reduced and a zero nominal lower interest rate (and thus the Friedman rule) is destabilizing. Given this, we can derive a “just stable” equilibrium nominal interest rate with matching definitions for inflation and monetary growth. We demonstrate that these implied lower bounds match their historical analogues well.
The Money Market Meltdown of the Great Depression
Authors: DUCA JOHN V.
Published: March 2013

Consistent with theories of financial frictions, this study finds that higher corporate risk premia and flight‐to‐quality events contributed to the increased use of a collateralized form of business lending (bankers acceptances) in real levels and relative to that of noncollateralized commercial paper (which plunged) during the Great Depression. These short‐lived instruments are more timely measures of credit availability than are bank/business failures and bank loan outstandings. These shifts in the composition of external finance were large, supporting the view that financial frictions rose and credit availability fell during the Great Depression.
Core Measures of Inflation as Predictors of Total Inflation
Authors: CRONE THEODORE M. , KHETTRY N. NEIL K. , MESTER LORETTA J. , NOVAK JASON A.
Published: March 2013

Policymakers tend to focus on core inflation measures because they are thought to be better predictors of total inflation over time horizons of import to policymakers. We find little support for this assumption. While some measures of core inflation are less volatile than total inflation, core inflation is not necessarily the best predictor of total inflation. The relative forecasting performance of models using core inflation and those using only total inflation depends on the inflation measure and time horizon of the forecast. Unlike previous studies, we provide a measure of the statistical significance of the difference in forecast errors.
The Long and Large Decline in State Employment Growth Volatility
Authors: CARLINO GERALD A. , DEFINA ROBERT , SILL KEITH
Published: March 2013

This study documents a general decline in the volatility of employment growth during the period 1956–2002 and examines its possible sources. We use a panel design that exploits the considerable state‐level variation in volatility during the period. The roles of monetary policy, oil prices, industrial employment shifts, and a coincident index of business cycle variables are explored. Overall, these four variables taken together explain as much as 31% of the fluctuations in employment growth volatility. Individually, each of the four factors is found to have significantly contributed to fluctuations in employment growth volatility, although to differing degrees.
Analysis of constant tissue remodeling in Syrian hamster Harderian gland: intra‐tubular and inter‐tubular syncytial masses
Authors: Coto‐Montes Ana , García‐Macía Marina , Caballero Beatriz , Sierra Verónica , Rodríguez‐Colunga María J. , Reiter Russel J. , Vega‐Naredo Ignacio
Published: March 2013

The Syrian hamster Harderian gland (HG) has a marked sexual dimorphism and exhibits an extraordinary rate of porphyrinogenesis. The physiological oxidative stress, derived from constant porphyrin production, is so high that the HG needs additional survival autophagic mechanisms to fight against this chronic exposure, provoking the triggering of a holocrine secretion in female glands that forms two types of secretory masses: intra‐tubular‐syncytial and inter‐tubular‐syncytial masses. The aim of this work was to study the development of this inter‐tubular holocrine secretion. To approach this task, we have considered that the steps developed during the formation of the so‐called invasive masses consist of the growth of epithelial cells, cell detachment from the basal lamina and invasion of surrounding tissues. The presence of these masses, particularly in the female HG, are closely linked to sexual dimorphism in redox balance and to alterations in the expression of certain factors such as cytokeratins, P‐cadherin, matrix metalloproteinases, cathepsin H, proliferating cell nuclear antigen, p53, CD‐31 and vascular endothelial growth factor, which seem to be involved in tissue remodeling. The results document unusual mechanisms of secretion in Syrian hamster HG: an extraordinary system of massive secretion through the conjunctive tissue, disrupting the branched structure of the gland.
Hysteroscopic management of displaced levonorgestrel‐releasing intrauterine system
Authors: Kuzel David , Hrazdirova Lucie , Kubinova Kristyna , Dundr Pavel , Cibula David , Mara Michal
Published: March 2013

Aim

This study was designed to evaluate feasibility and effectiveness of hysteroscopic intervention in the management of symptoms related to the displaced levonorgestrel‐releasing intrauterine system (LNG‐IUS).

Material and Methods

One hundred and thirteen patients with displaced LNG‐IUS presenting with irregular uterine bleeding, pelvic pain or asymptomatic displacement were recruited for hysteroscopic examination. Displaced LNG‐IUS was relocated by hysteroscopic intervention and the effect on symptoms and LNG‐IUS position was followed.

Results

The displaced LNG‐IUS was successfully relocated by hysteroscope in 112 (99.1%) of 113 cases. Following LNG‐IUS relocation, 71 (79.8%) patients of 89 with preoperative irregular uterine bleeding had amenorrhea or vaginal spotting, and 14 of 15 (93.3%) patients with preoperative pelvic pain became asymptomatic. LNG‐IUS expulsion was recorded in two patients 7 and 21 days after hysteroscopy.

Conclusion

Displaced LNG‐IUS can cause clinical symptoms (e.g. irregular bleeding, pain). Hysteroscopic relocation of displaced LNG‐IUS is a feasible method in the management of these symptoms. Risk of spontaneous expulsion associated with hysteroscopy is low.
Age at menarche and pregnancy‐related pelvic pain
Authors: Kirkeby Mette J. , Biering Karin , Olsen Jørn , Juhl Mette , Nohr Ellen A.
Published: March 2013

Aim

Menarcheal age is a predictor of several complications related to pregnancy and diseases later in life. We aimed to study if menarcheal age is a risk factor for pregnancy‐related pelvic pain.

Material and Methods

A nested case–control study was conducted within the Danish National Birth Cohort, a cohort of pregnant women, recruited during 1996–2002, and their children. In the second trimester of pregnancy the women provided information about age at menarche and potential confounders. Selection of cases (n = 2227) was based on self‐reported pelvic pain during pregnancy from an interview done 6 months post‐partum. The controls (n = 2588) were randomly selected among women who did not report pelvic pain. We used logistic regression analysis to calculate odds ratios (OR) for pregnancy‐related pelvic pain according to age at menarche.

Results

In the cohort, 18.5% of all pregnant women reported pregnancy‐related pelvic pain. Compared to women who were 12–14 years old at menarche, the adjusted OR for overall pelvic pain were 1.4 (95% confidence interval [CI] 1.1–1.7) in women 11 years or younger and 0.8 (95%CI 0.6–0.9) in women 15 years or older. The corresponding adjusted OR for severe pelvic pain were 1.6 (95%CI 1.3–2.0) and 0.7 (95%CI 0.6–0.9). When age was analyzed as a continuous variable, the odds for overall and severe pelvic pain decreased with 14% and 16%, respectively, for each increasing year.

Conclusions

The risk of pregnancy‐related pelvic pain decreased with increasing menarcheal age in an ‘exposure‐response’ pattern. A low menarcheal age is a risk indicator and may be a risk factor for pregnancy‐related pelvic pain.
Aster Yellows Subgroup 16SrI‐C Phytoplasma in Rhododendron hybridum
Authors: Přibylová Jaroslava , Špak Josef , Fránová Jana
Published: March 2013

Symptoms of unknown aetiology on Rhododendron hybridum cv. Cunningham's White were observed in the Czech Republic in 2010. The infected plant had malformed leaves, with irregular shaped edges, mosaic, leaf tip necrosis and multiple axillary shoots with smaller leaves. Transmission electron microscopy showed phytoplasma‐like bodies in phloem cells of the symptomatic plant. Phytoplasma presence was confirmed by polymerase chain reaction using phytoplasma‐specific, universal and group‐specific primer pairs. Restriction fragment length polymorphism analysis of 16S rDNA enabled classification of the detected phytoplasma into the aster yellows subgroup I‐C. Sequence analysis of the 16S‐23S ribosomal operon of the amplified phytoplasma genome from the infected rhododendron plant (1724 bp) confirmed the closest relationship with the Czech Echinacea purpurea phyllody phytoplasma. These data suggest Rhododendron hybridum is a new host for the aster yellows phytoplasma subgroup 16SrI‐C in the Czech Republic and worldwide.
Comparative accuracy of several published formulae for the estimation of serum osmolality in cats
Authors: Dugger D. T. , Mellema M. S. , Hopper K. , Epstein S. E.
Published: March 2013

Objective

To determine the osmole gap utilizing 18 previously published formulae for the estimation of serum osmolality in cats.

Procedures

Serum samples were frozen at −80°C after routine biochemical analysis. An Advanced Micro Osmometer 3300 was used to measure serum osmolality. Eighteen previously reported formulae were used to calculate osmolality from biochemical analysis results. The calculated osmolality was subtracted from the measured osmolality to determine the osmole gap. Osmole gaps for azotaemic and hyperglycaemic cats were compared to those from cats without azotaemia or hyperglycaemia using each formula.

Results

The osmole gaps varied dependent on the formula used and the presence or absence of hyperglycaemia or azotaemia. Eleven formulae led to calculated osmolality and osmole gaps that were not statistically different when hyperglycaemia, azotaemia or both were present. Four of these 11 formulae resulted in osmole gaps near zero. For each formula used, the osmole gap increased with increasing osmolality.

Clinical Significance

Multiple formulae to calculate serum osmolality can be used, but they result in significantly different osmole gaps. Clinicians should be aware of the specific reference interval for the formula being used. The formula [2(Na+) + glucose +BUN] is recommended as it is easy to use and reliable even in the presence of hyperglycaemia and/or azotaemia.
The efficacy of n‐butyl‐cyanoacrylate tissue adhesive for closure of canine laparoscopic ovariectomy port site incisions
Authors: Pope J. F. A. , Knowles T.
Published: March 2013

Objectives

To evaluate the efficacy of n‐butyl‐cyanoacrylate used to close port site skin incisions following canine laparoscopic ovariectomy and to assess owner attitudes to surgical adhesive.

Methods

The case records of dogs undergoing laparoscopic ovariectomy at a single centre during a 42‐month period were examined. Dogs with incisions closed with n‐butyl‐cyanoacrylate were included. Cases with less than 8 weeks follow‐up were excluded. Data relating to dehiscence, swelling, erythema, discharge or hypersensitivity postoperatively were recorded and reviewed. Postal questionnaires were sent to the dogs’ owners.

Results

A total of 289 dogs satisfied inclusion criteria. No complications occurred in 602 of 695 (86 · 6%) incisions. Complications occurred in 93 of 695 (13 · 4%) incisions: 33 of 695 (4 · 7%) dehisced, 38 of 695 (5 · 5%) swelled postoperatively, 59 of 695 (8 · 5%) developed erythema and 29 of 695 (4 · 2%) developed a discharge. Complications were significantly more likely for a 10 mm incision than for a 5 mm incision (P < 0 · 001). There were no reported cases of hypersensitivity relating to the use of n‐butyl‐cyanoacrylate, nor any long‐term adverse reactions. When owners scored incisions for scarring using a visual analogue scale (0: excellent, 10: poor) the mean and median scores were 0 · 7 and 0, respectively.

Clinical Significance

This study suggests that n‐butyl‐cyanoacrylate is an acceptable method for closing laparoscopic port sites in dogs.
Evaluation of accuracy of the Finnish elbow dysplasia screening protocol in Labrador retrievers
Authors: Lappalainen A. K. , Mölsä S. , Liman A. , Snellman M. , Laitinen‐Vapaavuori O.
Published: March 2013

Objective

To determine whether the current Finnish screening method using a single flexed mediolateral view as scored by osteophyte is sufficient to diagnose mild elbow dysplasia in Labrador retrievers and to determine if an additional craniocaudal oblique projection would result in improvement in the screening protocol.

Materials and Methods

Thirteen dogs with one mildly affected elbow joint and one elbow joint without radiological evidence of osteophytes were studied. Radiographic and computed tomography studies were performed and the results compared with each other.

Results

Medial compartment disease was observed in 14 of 26 joints based on computed tomography. The sensitivity and specificity of the grading based mainly on osteoarthritis was 79 and 92%, respectively. A strong association existed between elbow dysplasia based on computed tomography and medial humeral epicondylar osteophytes on the craniocaudal projection.

Clinical Significance

A single mediolateral flexed radiograph is reliable in diagnosing mild elbow dysplasia in Labrador retrievers. However, the craniocaudal oblique projection increases the specificity of the diagnosis, and it is proposed that it be included in the radiographic protocol in this breed.
Partial sleep restriction modulates secretory activity of thyrotropic axis in healthy men
Authors: Schmid Sebastian M. , Hallschmid Manfred , Jauch‐Chara Kamila , Kück Mareike C. , Lehnert Hendrik , Schultes Bernd
Published: March 2013

Sleep and endocrine function are known to be closely related, but studies on the effect of moderate sleep loss on endocrine axes are still sparse. We examined the influence of partial sleep restriction for 2 days on the secretory activity of the thyrotropic axis. Fifteen healthy, normal‐weight men were tested in a balanced, cross‐over study. Serum concentrations of thyrotrophin (TSH), free triiodothyronine (fT3) and free thyroxine (fT4) were monitored at 1‐h intervals during a 15‐h daytime period (08:00–23:00 h) following two nights of restricted sleep (bedtime 02:45–07:00 h) and two nights of regular sleep (bedtime 22:45–07:00 h), respectively. Serum concentrations of fT3 (P < 0.026) and fT4 (P = 0.089) were higher after sleep restriction than regular sleep, with a subsequent blunting of TSH concentrations in the evening hours of the sleep restriction condition (P = 0.008). These results indicate profound alterations in the secretory activity of the thyrotropic axis after 2 days of sleep restriction to ~4 h, suggesting that acute partial sleep loss impacts endocrine homeostasis, with potential consequences for health and wellbeing.
Clinical, polysomnographic and genome‐wide association analyses of narcolepsy with cataplexy: a European Narcolepsy Network study
Authors: Luca Gianina , Haba‐Rubio José , Dauvilliers Yves , Lammers Gert‐Jan , Overeem Sebastiaan , Donjacour Claire E. , Mayer Geert , Javidi Sirous , Iranzo Alex , Santamaria Joan , Peraita‐Adrados Rosa , Hor Hyun , Kutalik Zoltan , Plazzi Giuseppe , Poli Francesca , Pizza Fabio , Arnulf Isabelle , Lecendreux Michel , Bassetti Claudio , Mathis Johannes , Heinzer Raphael , Jennum Poul , Knudsen Stine , Geisler Peter , Wierzbicka Aleksandra , Feketeova Eva , Pfister Corinne , Khatami Ramin , Baumann Christian , Tafti Mehdi ,   European Narcolepsy Network (EU‐NN)
Published: March 2013

The aim of this study was to describe the clinical and PSG characteristics of narcolepsy with cataplexy and their genetic predisposition by using the retrospective patient database of the European Narcolepsy Network (EU‐NN). We have analysed retrospective data of 1099 patients with narcolepsy diagnosed according to International Classification of Sleep Disorders‐2. Demographic and clinical characteristics, polysomnography and multiple sleep latency test data, hypocretin‐1 levels, and genome‐wide genotypes were available. We found a significantly lower age at sleepiness onset (men versus women: 23.74 ± 12.43 versus 21.49 ± 11.83, P = 0.003) and longer diagnostic delay in women (men versus women: 13.82 ± 13.79 versus 15.62 ± 14.94, P = 0.044). The mean diagnostic delay was 14.63 ± 14.31 years, and longer delay was associated with higher body mass index. The best predictors of short diagnostic delay were young age at diagnosis, cataplexy as the first symptom and higher frequency of cataplexy attacks. The mean multiple sleep latency negatively correlated with Epworth Sleepiness Scale (ESS) and with the number of sleep‐onset rapid eye movement periods (SOREMPs), but none of the polysomnographic variables was associated with subjective or objective measures of sleepiness. Variant rs2859998 in UBXN2B gene showed a strong association (P = 1.28E‐07) with the age at onset of excessive daytime sleepiness, and rs12425451 near the transcription factor TEAD4 (P = 1.97E‐07) with the age at onset of cataplexy. Altogether, our results indicate that the diagnostic delay remains extremely long, age and gender substantially affect symptoms, and that a genetic predisposition affects the age at onset of symptoms.
High‐frequency sampling and kernel estimation for continuous‐time moving average processes
Authors: Brockwell Peter J. , Ferrazzano Vincenzo , Klüppelberg Claudia
Published: March 2013

Interest in continuous‐time processes has increased rapidly in recent years, largely because of high‐frequency data available in many applications. We develop a method for estimating the kernel function g of a second‐order stationary Lévy‐driven continuous‐time moving average (CMA) process Y based on observations of the discrete‐time process YΔ obtained by sampling Y at Δ, 2Δ, …, nΔ for small Δ. We approximate g by gΔ based on the Wold representation and prove its pointwise convergence to g as Δ → 0 for continuous‐time autoregressive moving average (CARMA) processes. Two non‐parametric estimators of gΔ, on the basis of the innovations algorithm and the Durbin–Levinson algorithm, are proposed to estimate g. For a Gaussian CARMA process, we give conditions on the sample size n and the grid spacing Δ(n) under which the innovations estimator is consistent and asymptotically normal as n → ∞. The estimators can be calculated from sampled observations of any CMA process, and simulations suggest that they perform well even outside the class of CARMA processes. We illustrate their performance for simulated data and apply them to the Brookhaven turbulent wind speed data. Finally, we extend results of Brockwell et al. (2012) for sampled CARMA processes to a much wider class of CMA processes.
Tunica Vaginalis Pedicle Flap for Reconstruction of Anterior Urethral Stricture
Authors: YAQUBI Abdul‐Ali , YUAN Wu Wen , MEI Shen Hong , XIONG Jin Tie
Published: March 2013

Objective

To evaluate the intermediate‐term clinical efficacy and success rate of tunica vaginalis (TV) pedicle flap for reconstruction of bulbo‐penile urethral stricture.

Methods

We assessed the medical records of 15 male patients who had undergone TV pedicle flap urethroplasty for reconstruction of anterior urethral stricture between January 2006 and December 2011. The surgical outcome was assessed by comparison of four parameters including the maximum flow rate (Qmax), international prostate symptom score (IPSS), residual urine (RU) and quality of life (QOL) in all patients pre‐ and postoperatively. Moreover, pre‐ and postoperative retrograde urethrography films were compared in all patients. t‐test was used for data analysis.

Results

The mean patient age was 38.1 ± 9.3 years (range: 25–55), mean stricture length was 4.2 ± 1.1 cm (range: 3–6.1 cm), and the mean follow up time was 14.6 ± 1.9 months (range: 12–18) months. There was a statistically significant difference between Q(max), IPSS, RU and QOL pre‐ and postoperatively (P < 0.01). The clinical success rate in this study was 86.6% (13/15). The early complication was one case of wound infection and subsequent wound dehiscence, one case of hematoma formation in another patient, which did not have any influence in the long‐term clinical outcome.

Conclusion

At intermediate‐term follow up, TV pedicle flap urethroplasty has a high clinical success rate with low complication. However, a large clinical trial with long‐term follow up is needed to confirm the result.
Conclusive evidence for panmixia in the American eel
Authors: Pujolar Jose M.
Published: March 2013

Eels are unique species in the biological world. The two North Atlantic eel species, the American eel (Anguilla rostrata) and the European eel (A. anguilla), occupy a broad range of habitats from the Caribbean to Greenland in the western Atlantic and from Morocco to Iceland in the eastern Atlantic, respectively. North Atlantic eels have a catadromous life cycle, spawning only in the Sargasso Sea and spending the majority of their lives in continental (fresh, brackish and coastal) waters. Despite such a wide distribution range, North Atlantic eels have been regarded as a textbook example of panmictic species. In contrast with the large amount of population genetic studies testing the panmixia hypothesis in the European eel, a relatively modest effort has been given to study the population structure of the American eel. In this issue of Molecular Ecology, Côté et al. () present the most comprehensive American eel data set to date, which includes samples of different life stages obtained throughout all its distribution range in North America. Results show a total lack of genetic differentiation among samples and provide decisive evidence for panmixia in the American eel.
Ancient DNA supports southern survival of Richardson's collared lemming (Dicrostonyx richardsoni) during the last glacial maximum
Authors: Fulton Tara L. , Norris Ryan W. , Graham Russell W. , Semken Holmes A. , Shapiro Beth
Published: March 2013

Collared lemmings (genus Dicrostonyx) are circumpolar Arctic arvicoline rodents associated with tundra. However, during the last glacial maximum (LGM), Dicrostonyx lived along the southern ice margin of the Laurentide ice sheet in communities comprising both temperate and boreal species. To better understand these communities and the fate of these southern individuals, we compare mitochondrial cytochrome b sequence data from three LGM‐age Dicrostonyx fossils from south of the Laurentide ice sheet to sequences from modern Dicrostonyx sampled from across their present‐day range. We test whether the Dicrostonyx populations from LGM‐age continental USA became extinct at the Pleistocene–Holocene transition ~11000 years ago or, alternatively, if they belong to an extant species whose habitat preferences can be used to infer the palaeoclimate along the glacial margin. Our results indicate that LGM‐age Dicrostonyx from Iowa and South Dakota belong to Dicrostonyx richardsoni, which currently lives in a temperate tundra environment west of Hudson Bay, Canada. This suggests a palaeoclimate south of the Laurentide ice sheet that contains elements similar to the more temperate shrub tundra characteristic of extant D. richardsoni habitat, rather than the very cold, dry tundra of the Northern Arctic. While more data are required to determine whether or not the LGM southern population is ancestral to extant D. richardsoni, it seems most probable that the species survived the LGM in a southern refugium.
Investigating a possible role for the bacterial signal molecules N‐acylhomoserine lactones in Balanus improvisus cyprid settlement
Authors: Tait Karen , Havenhand Jon
Published: March 2013

Increased settlement on bacterial biofilms has been demonstrated for a number of marine invertebrate larvae, but the nature of the cue(s) responsible is not well understood. We tested the hypothesis that the bay barnacle Balanus improvisus utilizes the bacterial signal molecules N‐acylhomoserine lactones (AHLs) as a cue for the selection of sites for permanent attachment. Single species biofilms of the AHL‐producing bacteria Vibrio anguillarum, Aeromonas hydrophila and Sulfitobacter sp. BR1 were attractive to settling cypris larvae of B. improvisus. However, when AHL production was inactivated, either by mutation of the AHL synthetic genes or by expression of an AHL‐degrading gene (aiiA), the ability of the bacteria to attract cyprids was abolished. In addition, cyprids actively explored biofilms of E. coli expressing the recombinant AHL synthase genes luxI from Vibrio fischeri (3‐oxo‐C6‐HSL), rhlI from Pseudomonas aeruginosa (C4‐HSL/C6‐HSL), vanI from V. anguillarum (3‐oxo‐C10‐HSL) and sulI from Sulfitobacter sp. BR1 (C4‐HSL, 3‐hydroxy‐C6‐HSL, C8‐HSL and 3‐hydroxy‐C10‐HSL), but not E. coli that did not produce AHLs. Finally, synthetic AHLs (C8‐HSL, 3‐oxo‐C10‐HSL and C12‐HSL) at concentrations similar to those found within natural biofilms (5 μm) resulted in increased cyprid settlement. Thus, B. improvisus cypris exploration of and settlement on biofilms appears to be mediated by AHL‐signalling bacteria in the laboratory. This adds to our understanding of how quorum sensing inhibition may be used as for biofouling control. Nonetheless, the significance of our results for larvae settling naturally in the field, and the mechanisms that underlay the observed responses to AHLs, is as yet unknown.
Urban land use limits regional bumble bee gene flow
Authors: Jha Shalene , Kremen C.
Published: March 2013

Potential declines in native pollinator communities and increased reliance on pollinator‐dependent crops have raised concerns about native pollinator conservation and dispersal across human‐altered landscapes. Bumble bees are one of the most effective native pollinators and are often the first to be extirpated in human‐altered habitats, yet little is known about how bumble bees move across fine spatial scales and what landscapes promote or limit their gene flow. In this study, we examine regional genetic differentiation and fine‐scale relatedness patterns of the yellow‐faced bumble bee,Bombus vosnesenskii,to investigate how current and historic habitat composition impact gene flow. We conducted our study across a landscape mosaic of natural, agricultural and urban/suburban habitats, and we show thatB. vosnesenskiiexhibits low but significant levels of differentiation across the study system (FST = 0.019,Dest = 0.049). Most importantly, we reveal significant relationships between pairwiseFSTand resistance models created from contemporary land use maps. Specifically,B. vosnesenskiigene flow is most limited by commercial, industrial and transportation‐related impervious cover. Finally, our fine‐scale analysis reveals significant but declining relatedness between individuals at the 1–9 km spatial scale, most likely due to local queen dispersal. Overall, our results indicate thatB. vosnesenskiiexhibits considerable local dispersal and that regional gene flow is significantly limited by impervious cover associated with urbanization.
Development of genetic diversity, differentiation and structure over 500 years in four ponderosa pine populations
Authors: Lesser M. R. , Parchman T. L. , Jackson S. T.
Published: March 2013

Population history plays an important role in shaping contemporary levels of genetic variation and geographic structure. This is especially true in small, isolated range‐margin populations, where effects of inbreeding, genetic drift and gene flow may be more pronounced than in large continuous populations. Effects of landscape fragmentation and isolation distance may have implications for persistence of range‐margin populations if they are demographic sinks. We studied four small, disjunct populations of ponderosa pine over a 500‐year period. We coupled demographic data obtained through dendroecological methods with microsatellite data to discern how and when contemporary levels of allelic diversity, among and within‐population levels of differentiation, and geographic structure, arose. Alleles accumulated rapidly following initial colonization, demonstrating proportionally high levels of gene flow into the populations. At population sizes of approximately 100 individuals, allele accumulation saturated. Levels of genetic differentiation among populations (FSTand Jost'sDest) and diversity within populations (FIS) remained stable through time. There was no evidence of geographic genetic structure at any time in the populations' history. Proportionally, high gene flow in the early stages of population growth resulted in rapid accumulation of alleles and quickly created relatively homogenous genetic patterns among populations. Our study demonstrates that contemporary levels of genetic diversity were formed quickly and early in population development. How contemporary genetic diversity accumulates over time is a key facet of understanding population growth and development. This is especially relevant given the extent and speed at which species ranges are predicted to shift in the coming century.
Genetic signature of a range expansion and leap‐frog event after the recent invasion of Europe by the grapevine downy mildew pathogen Plasmopara viticola
Authors: Fontaine Michael C. , Austerlitz Fréderic , Giraud Tatiana , Labbé Frédéric , Papura Daciana , Richard‐Cervera Sylvie , Delmotte François
Published: March 2013

Biologic invasions can have important ecological, economic and social consequences, particularly when they involve the introduction and spread of plant invasive pathogens, as they can threaten natural ecosystems and jeopardize the production of human food. Examples include the grapevine downy mildew, caused by the oomycete Plasmopara viticola, an invasive species native to North America, introduced into Europe in the 1870s. We investigated the introduction and spread of this invasive pathogen, by analysing its genetic structure and diversity in a large sample from European vineyards. Populations of P. viticola across Europe displayed little genetic diversity, consistent with the occurrence of a bottleneck at the time of introduction. Bayesian coalescent analyses revealed a clear population expansion signal in the genetic data. We detected a weak, but significant, continental‐wide population structure, with two geographically and genetically distinct clusters in Western and Eastern European vineyards. Approximate Bayesian computation, analyses of clines of genetic diversity and of isolation‐by‐distance patterns provided evidence for a wave of colonization moving in an easterly direction across Europe. This is consistent with historical reports, first mentioning the introduction of the disease in Bordeaux vineyards (France) and sub‐sequently documenting its rapid spread across Europe. This initial introduction in the west was probably followed by a ‘leap‐frog’ event into Eastern Europe, leading to the formation of the two genetic clusters we detected. This study shows that recent population genetics methods within the Bayesian and coalescence frameworks are extremely powerful for increasing our understanding of pathogen population dynamics and invasion histories.
A Two‐Step Model Updating Algorithm for Parameter Identification of Linear Elastic Damped Structures
Authors: García‐Palencia Antonio Javier , Santini‐Bell Erin
Published: March 2013

A Frequency Response Functions (FRFs)‐based two‐step algorithm to identify stiffness, mass, and viscous damping matrices is developed in this work. The proposed technique uses the difference between the experimentally recorded FRF and their analytical counterparts by minimizing the resultant error function at selected frequency points. In the first step, only mass and stiffness matrices are updated while keeping the uncalibrated viscous damping matrix constant. In the second step, the damping matrix is updated via changes on the selected unknown modal damping ratios. By using a stacking procedure of the presented error function that combines multiple data sets, adverse effects of noise on the estimated modal damping ratios are decreased by averaging the FRF amplitudes at resonant peaks. The application of this methodology is presented utilizing experimentally obtained data. The presented algorithm can perform an accurate structural identification via model updating, with a viscous damping matrix that captures the variation of the modal damping ratios with natural frequencies as opposed to other conventional proportional damping matrix formulations.
In vitro antifungal activity of topical and systemic antifungal drugs against Malassezia species
Authors: Carrillo‐Muñoz Alfonso Javier , Rojas Florencia , Tur‐Tur Cristina , de los Ángeles Sosa María , Diez Gustavo Ortiz , Espada Carmen Martín , Payá María Jesús , Giusiano Gustavo
Published: March 2013

The strict nutritional requirements of Malassezia species make it difficult to test the antifungal susceptibility. Treatments of the chronic and recurrent infections associated with Malassezia spp. are usually ineffective. The objective of this study was to obtain in vitro susceptibility profile of 76 clinical isolates of Malassezia species against 16 antifungal drugs used for topical or systemic treatment. Isolates were identified by restriction fragment length polymorphism. Minimal inhibitory concentrations (MIC) were obtained by a modified microdilution method based on the Clinical Laboratory Standards Institute reference document M27‐A3. The modifications allowed a good growth of all tested species. High in vitro antifungal activity of most tested drugs was observed, especially triazole derivatives, except for fluconazole which presented the highest MICs and widest range of concentrations. Ketoconazole and itraconazole demonstrated a great activity. Higher MICs values were obtained with Malassezia furfur indicating a low susceptibility to most of the antifungal agents tested. Malassezia sympodialis and Malassezia pachydermatis were found to be more‐susceptible species than M. furfur, Malassezia globosa, Malassezia slooffiae and Malassezia restricta. Topical substances were also active but provide higher MICs than the compounds for systemic use. The differences observed in the antifungals activity and interspecies variability demonstrated the importance to studying the susceptibility profile of each species to obtain reliable information for defining an effective treatment regimen.
Crohn's disease: small bowel motility impairment correlates with inflammatory‐related markers C‐reactive protein and calprotectin
Authors: Bickelhaupt S. , Pazahr S. , Chuck N. , Blume I. , Froehlich J. M. , Cattin R. , Raible S. , Bouquet H. , Bill U. , Rogler G. , Frei P. , Boss A. , Patak M. A
Published: March 2013

Background

To evaluate the correlation between the levels of C‐reactive protein (CRP), calprotectin, and small bowel motility in patients with Crohn's disease assessed with MRI.

Methods

This prospective institutional review board approved study included magnetic resonance imaging enterography (MRE) and analyses of inflammatory markers in blood (C‐reactive protein) and feces (calprotectin). For cine MRE, a coronal 2D‐T2w sequence was used on a 1.5 T MRI system. Small bowel motility was analyzed in 13 patients using dedicated magnetic resonance MR‐motility assessment software (Motasso). Contraction frequency, amplitude, amplitude diameter ratio, and luminal diameter were determined as well as the blood levels of CRP (mg L−1) and fecal levels of calprotectin (ug g−1). Statistics were calculated using Pearson's correlation coefficient.

Key Results

A significant inverse linear correlation was found between the contraction frequency and both the level of CRP (r = −0.701, P = 0.008) and calprotectin (r = −0.805, P = 0.001). Dilatation of small bowel diameter significantly correlated with calprotectin levels (r = 0.857, P =< 0.001) but not with CRP (r = 0.447, P = 0.126). The absolute amplitude of the contractions did not correlate neither with the level of CRP (r = −0.527, P = 0.064) nor with calprotectin (r = −0.612, P = 0.026). The ratio describing the contraction amplitude relatively to the individual luminal diameter significantly correlated with calprotectin (r = 0.736, P = 0.004) and with CRP (r = 0.577, P = 0.039).

Conclusions & Inferences

Alterations of small bowel motility during CD flares significantly correlate with the level of calprotectin and CRP indicating that they represent inflammatory activity.
3‐D imaging, illustration, and quantitation of enteric glial network in transparent human colon mucosa
Authors: Liu Y. A. , Chung Y. C. , Pan S. T. , Shen M. Y. , Hou Y. C. , Peng S. J. , Pasricha P. J. , Tang S. C.
Published: March 2013

Background

Enteric glia form a network in the intestinal mucosa and have been suggested to engage in multidirectional interactions with the epithelium, blood vessels, nerves, and immune system. However, due to the dispersed nature of the glial network, standard histology cannot provide a global view of the network architecture. We prepared transparent human colon mucosa for three‐dimensional (3‐D) confocal microscopy with S100B immunostaining to reveal the location‐dependent glial network for qualitative and quantitative analyses.

Methods

Full‐thickness human colons were acquired from colectomies performed for colorectal cancer. We targeted the mucosa away from the tumor site to characterize the glial network morphology. Optical clearing (use of immersion solution to reduce scattering) was applied to generate transparent specimens for deep‐tissue microscopy.

Key Results

Two features of the glial network were seen: (i) A dense glial population resides at the crypt base/mucosal boundary in contact with the lymphatic vessels, and (ii) from the base, the glial network elongates along the crypt axis with peri‐cryptic and peri‐vascular connections toward the opening. We quantified the mucosal glia as the S100B‐positive cells with at least two processes extending from the cell body. Examples of the global and in‐depth imaging of adenoma were given to illustrate the morphological correlation between the loss of glial fibers and the aberrant crypts.

Conclusions & Inferences

We have established a useful approach for 3‐D imaging, panoramic illustration, and quantitation of the enteric glia in the human colon mucosa to help characterize their roles with mucosal components in health and disease.
Spatial and temporal dynamics of the colonization ofPinus radiatabyFusarium circinatum, of conidiophora development in the pith and of traumatic resin duct formation
Authors: Martín‐Rodrigues Noemí , Espinel Santiago , Sanchez‐Zabala Joseba , Ortíz Amaia , González‐Murua Carmen , Duñabeitia Miren K.
Published: March 2013

Fusarium circinatumcauses pitch canker disease in a wide range of pine trees, includingPinus radiata, with devastating economic consequences.

To assess the spatial and temporal dynamics of growth of this pathogen in radiata pine, we examined the process of infection using both real‐timePCRto quantify fungal biomass inside the plant host, and confocal microscopy using a green fluorescent protein (GFP)‐tagged strain ofF. circinatum.

Pathogen growth exhibited three distinct phases: an initial exponential increase in fungal biomass, concomitant with pathogen colonization of the cortex and phloem; a slowdown in fungal growth coincident with sporulating hyphae deep within the host; and stabilization of the fungal biomass when the first wilting symptoms appeared. The number of resin ducts in the xylem was found to increase in response to infection and the fungus grew inside both constitutive and traumatic resin ducts.

These results indicate that conidiation may contribute to the spatial or temporal dissemination of the pathogen. Moreover, the present findings raise the intriguing possibility that the generation of traumatic resin ducts may be of more benefit to the fungus than to the plant.
Evolutionary and molecular analysis of Dof transcription factors identified a conserved motif for intercellular protein trafficking
Authors: Chen Huan , Ahmad Munawar , Rim Yeonggil , Lucas William J. , Kim Jae‐Yean
Published: March 2013

Cell‐to‐cell trafficking of transcription factors (TFs) has been shown to play an important role in the regulation of plant developmental events, but the evolutionary relationship between cell‐autonomous and noncell‐autonomous (NCA) TFs remains elusive.

AtDof4.1, named INTERCELLULAR TRAFFICKING DOF 1 (ITD1), was chosen as a representative NCA member to explore this evolutionary relationship. Using domain structure–function analyses and swapping studies, we examined the cell‐to‐cell trafficking of plant‐specific Dof TF family members across Arabidopsis and other species.

We identified a conserved intercellular trafficking motif (ITM) that is necessary and sufficient for selective cell‐to‐cell trafficking and can impart gain‐of‐function cell‐to‐cell movement capacity to an otherwise cell‐autonomous TF. The functionality of related motifs from Dof members across the plant kingdom extended, surprisingly, to a unicellular alga that lacked plasmodesmata. By contrast, the algal homeodomain related to the NCA KNOX homeodomain was either inefficient or unable to impart such cell‐to‐cell movement function.

The Dof ITM appears to predate the evolution of selective plasmodesmal trafficking in the plant kingdom, which may well have acted as a molecular template for the evolution of Dof proteins as NCA TFs. However, the ability to efficiently traffic for KNOX homeodomain (HD) proteins may have been acquired during the evolution of early nonvascular plants.
‘You monitor performance at every hour’: labour and the management of performance in the supermarket supply chain
Authors: Newsome Kirsty , Thompson Paul , Commander Johanna
Published: March 2013

With reference to the performance management research agenda, this article focuses on the politics of production in food manufacturing and distribution companies in the supermarket supply chain. Burawoy's concept of ‘factory regimes’ is utilised to explore the broader context of labour process change in inter‐linked organisations in the retail supply chain. The article examines the extent to which new despotic or coercive regime characteristics are emerging that weakens the power of both suppliers and labour. In revealing changes in the nature and dynamics of performance regimes within these organisations, the article exposes the connections and linkages between workplaces as distinct moments in the integrated circuit of capital.
Mapping the antecedents of telework diffusion: firm‐level evidence from Italy
Authors: Neirotti Paolo , Paolucci Emilio , Raguseo Elisabetta
Published: March 2013

Previous literature has studied telework practices predominantly from the employees' perspective rather than exploring its use at the firm level. With the objective of contributing to reducing this research gap, the relationship between firms' adoption of telework and the firms' technological, organisational and environmental contexts is explored. Data were obtained from a survey conducted between 2005 and 2009 on a sample of 1,134 Italian firms in the Piedmont region. The results show an overall increase in the diffusion of telework primarily attributable to a rise in the adoption of ‘mobile’ work rather than home‐based forms of telework. The results also show that firms that had previously adopted information systems supporting core business processes and knowledge management were more inclined to adopt telework. Telework arrangements were more widely diffused among firms facing a growing and geographically dispersed market demand, and also in the contexts of higher levels of human capital and lower capital intensity.