bluuebunny/crossref_metadata_2025 huggingface dataset:
Risk Factors for the Development of Metachronous Liver Metastasis in Colorectal Cancer Patients After Curative Resection
Authors: Chuang Shih‐Chang , Su Yu‐Chung , Lu Chien‐Yu , Hsu Hung‐Te , Sun Li‐Chu , Shih Ying‐Ling , Ker Chen‐Guo , Hsieh Jan‐Sing , Lee King‐Teh , Wang Jaw‐Yuan
Published: December 2010

Background

Metachronous liver metastasis (MLM) occurs in 20–40% of colorectal cancer (CRC) patients following surgical treatment. The aim of the present study was to determine the risk factors affecting the development of MLM in CRC patients following curative resection.

Methods

A total of 1,356 patients who underwent curative intent resection for CRC were retrospectively studied. Of these patients, those who with 30 days postoperative mortality (n = 23), incomplete medical record (n = 32), synchronous liver metastasis (n = 148) and UICC stage IV (n = 54) were excluded, and finally 1,099 patients were analyzed, including 977 patients without liver metastasis and 122 patients with MLM‐only. Clinical and pathological records for each patient were reviewed from medical charts. The clinicopathologic characteristics of 1,099 patients were investigated.

Results

The median timing of developing MLM was 13 months with a range of 4 to 79 months. Univariate analysis identified that preoperative serum carcinoembryonic antigen (CEA) level, depth of invasion, lymph nodes metastasis, vascular invasion, and perineural invasion were significantly correlated with the development of MLM (all P < 0.05). Meanwhile, a multivariate analysis showed that preoperative serum carcinoembryonic antigen (CEA) level > 5 ng/ml (Odds Ratio [OR] = 1.591; 95% Confidence Interval [CI], 1.065–2.377; P = 0.024), tumor depth (OR = 2.294; 95% CI, 1.103–4.768; P = 0.026), positive lymph node metastasis (OR = 2.004; 95% CI, 1.324–3.031; P = 0.001) and positive vascular invasion (OR = 1.872; 95% CI, 1.225–2.861; P = 0.004) were independent prognostic factors contributing to the occurrence of MLM.

Conclusions

The present study demonstrates that preoperative serum CEA level, tumor depth, lymph node metastasis, and positive vascular invasion could affect the occurrence of MLM in CRC patients following curative resection, and thus could help to define these high‐risk patients who would benefit from enhanced surveillance and therapeutic program(s).
Analysis of the Clinicopathologic Features of Papillary Thyroid Microcarcinoma Based on 7‐mm Tumor Size
Authors: Lee Kwan Ju , Cho Yun Jung , Kim Say Jun , Lee Sang Chul , Kim Jeong Goo , Ahn Chang Joon , Lee Dong Ho
Published: December 2010

Background

We examined the clinicopathologic features of papillary thyroid microcarcinomas (PTMCs) measuring ≤7 mm and compared them with those of PTMCs >7 mm.

Methods

Between January 2007 and June 2009, a total of 275 patients with PTMCs underwent surgery. They were divided into two groups. Group I included patients with tumors ≤7 mm, and group II included those with tumors >7 mm but ≤10 mm. We compared the two groups’ clinicopathologic features.

Results

Total thyroidectomy was more often performed in group II (p = 0.003). Central lymph node metastases were identified in 30.6% of the patients in group I and in 47.8% of the patients in group II (p = 0.005). A statistically significant difference between the two groups was also found for capsule invasion (p < 0.0001), extrathyroidal extension (p = 0.005), and lymphovascular invasion (p = 0.025). On the multivariate analysis, central lymph node metastasis was the only independent factor associated with tumor size.

Conclusion

A PTMC ≤7 mm is less likely to have aggressive features, including central lymph node metastasis, capsule invasion, extrathyroidal extension, and lymphovascular invasion, than a PTMC >7 mm. Because the aggressiveness of PTMC was found mainly in the patients with tumors >7 mm, we think that a cutoff value of 7 mm may be considered the threshold of aggressiveness of PTMCs.
Computed Tomography Volumetric Fat Parameters versus Body Mass Index for Predicting Short‐term Outcomes of Colon Surgery
Authors: Cecchini Stefano , Cavazzini Egildo , Marchesi Federico , Sarli Leopoldo , Roncoroni Luigi
Published: December 2010

Background

At present, the impact of obesity on short‐term outcomes of general surgery remains controversial, especially in the field of laparoscopy. Most studies on the subject have used the body mass index (BMI) to define obesity without distinguishing between visceral and subcutaneous storage. Computed tomography (CT) volumetric analysis permits accurate evaluation of site‐specific volume of adipose tissue. The purpose of this study was to compare CT volumetric fat parameters and the BMI for predicting short‐term outcomes of colon surgery.

Methods

A retrospective analysis was conducted of 231 consecutive patients undergoing elective colon resection, with open or laparoscopic technique, from January 2007 to April 2009. CT volumetric quantification of abdominal visceral and subcutaneous adipose tissue was performed. Intraoperative and perioperative data were collected.

Results

A total of 187 patients were enrolled. BMI showed a direct correlation with fat volumetric parameters but not with the visceral/subcutaneous fat ratio. Operating time was correlated with subcutaneous fat storage and BMI in the laparoscopic right colectomy subgroup. No associations were found with the conversion rate. Length of the hospital stay was correlated with the visceral/subcutaneous fat ratio in the laparoscopic left colectomy subgroup. Whereas the overall postoperative complication rate and mortality were not associated with fat parameters, the postoperative surgical complication rate was associated with visceral volumetric parameters in the laparoscopic left colectomy subgroup.

Conclusions

Short‐term outcomes of colon surgery are better predicted by fat volumetric parameters than by the BMI. This study has provided new elements for discussion on the impact of visceral and subcutaneous adiposity in laparoscopic and traditional colon surgery.
Reference Accuracy in the General Surgery Literature
Authors: Awrey Julianne , Inaba Kenji , Barmparas Galinos , Recinos Gustavo , Teixeira Pedro G. R. , Chan Linda S. , Talving Peep , Demetriades Demetrios
Published: December 2010

Background

Reference inaccuracy in scientific articles brings the scientific validity of the research into question and may create difficulty when accessing the cited background data. The objective of this study was to examine the reference accuracy in the general surgery literature and its correlation with the journal impact factor.

Methods

Five general surgery journals were chosen with varying impact factors. From the year 2007, one issue was randomly chosen from each journal, and from each issue 180 citations were randomly chosen for review. Three investigators evaluated the chosen references for primary, citational, and quotational errors. The impact factor of each journal was compared to the percentage of errors detected.

Results

The total number of errors per journal ranged from 31.3 to 39.3%, with a total of 35.4% of all citations reviewed containing some type of error. The most common error type detected was incorrect citation of the primary source supporting a statement, the incidence of which ranged from 13.8 to 25.2%, depending on the journal, and accounting for 53.6% of the total errors found. Citational errors, which included incorrect author names, pagination, dates, and issue and volume numbers, ranged from 1.8 to 18.1% and accounted for 20.4% of the total errors detected. Qualitative errors, which occurred when the author misquoted another author’s written assertions or conclusions, ranged from 7.4 to 16.0% and accounted for 34.7% of the total errors detected. Quantitative errors (misquoted numerical data) ranged from 3.1 to 8.6% and accounted for 17.9% of the total errors detected. No association between impact factor and error rate was demonstrated.

Conclusions

Reference inaccuracy is common in the general surgery literature. The impact factor has no clear association with the error rate, demonstrating that journal quality does not necessarily correlate with reference quality. Further investigation into potential methods for improving reference accuracy in the general surgery literature is warranted.
Single port laparoscopic cholecystectomy: which technique, which surgeon, for which patient? A study of the implementation in a teaching hospital
Authors: Mutter D. , Callari C. , Diana M. , Dallemagne B. , Leroy J. , Marescaux J.
Published: December 2010

Background

Single port cholecystectomy is increasingly performed. This procedure can be challenging, and we lack factors predicting the operative difficulty.

Aims

To assess the role of surgeon experience and identify possible predictive factors of intraoperative difficulties.

Patients and methods

Sixty‐one selected patients were prospectively enrolled between January 2008 and August 2010. Six surgeons were involved (3 seniors, 3 juniors).

Anthropometrics of the patients, types of ports, exposure methods and intraoperative data were recorded. Pain was assessed with the visual analogic scale at postoperative day 1 (POD 1 VAS).

Results

Fifty‐eight patients with symptomatic gallstones and three with acute cholecystitis underwent single port cholecystectomy. The mean BMI, weight and height were 25.7 kg/m2 (SD 4.45), 71.8 kg (SD 14.83) and 166 cm SD 0.07, respectively. Mean operative time was 68.4 min (SD 26.98). Anthropometrics had no influence on operative time. Senior surgeons performed more rapidly, but the difference was not significant. The overall mean POD 1 VAS was 2.26, (SD 1.81). The mean hospital stay was 2.22 days, (SD 0.9). No complications occurred. An additional exposure method was necessary in 19 procedures. This cluster presented a significantly higher operating time (81.5 min, SD 31.69 vs. 62.7, SD 22.74;p = 0.01) and POD 1 VAS (1.92 vs. 3;p = 0.031).

Conclusion

Single trocar cholecystectomy can be implemented safely in teaching hospitals. Anthropometrics are not predictive of operative difficulties. The need for additional exposure systems affects the operative time and pain negatively, reflecting greater technical difficulties. Research to optimize instruments may help to solve these problems.
Surface Properties and Micellar Molecular Interaction in Binary Systems of a Biosurfactant Sodium Deoxycholate (NaDC) with Conventional Surfactants
Authors: Wang Zhongni , Wu Tonghao , Zhou Wu , Wei Xilian , Zhao Jing
Published: December 2010

Surface tension for the binary mixtures of a biosurfactant sodium deoxycholate (NaDC) with three different conventional surfactants (p‐(1,1,3,3‐tetramethylbutyl)phenol polyoxyethylene, polyoxethylene‐10‐oleyl ether, and sodium oleate) were measured in buffer solutions at different temperatures. Surface properties were determined as well as the micellar characteristics like composition, micellar molecular interaction parameter (β), activity coefficients (f1, f2), and the free energy of micellization were analyzed using some theoretical models, including Clint, Rubingh, Motomura and Maeda models. The results reveal that all the three investigated systems show non‐ideality in the micelle formation by the deviation in the experimental critical micelle concentration (CMC), f1, f2, and negative β values from the ideal values. The proportion of NaDC in the mixed micelle (X1) calculated by all models increases with increasing the molar fraction of NaDC in solution (αNaDC), but the X1 values are very small even at the high αNaDC. Moreover, by using the Maeda theory, the results suggest the chain‐chain interaction among surfactants does not seem to be strong. It is noted that two break points were observed in the surface tension plots of pure NaOL and NaDC/NaOL mixture solutions. Interestingly, by introducing moderate NaDC or decreasing the temperature, the first break point disappeared for the two systems.
The Health Promoting Properties of the Conjugated Isomers of α‐Linolenic Acid
Authors: Hennessy Alan A. , Ross R. Paul , Devery Rosaleen , Stanton Catherine
Published: December 2010

The bioactive properties of the conjugated linoleic acid (CLA) isomers have long been recognised and are the subject of a number of excellent reviews. However, despite this prominence the CLA isomers are not the only group of naturally occurring dietary conjugated fatty acids which have shown potent bioactivity. In a large number of in vitro and in vivo studies, conjugated α‐linolenic acid (CLNA) isomers have displayed potent anti‐inflammatory, immunomodulatory, anti‐obese and anti‐carcinogenic activity, along with the ability to improve biomarkers of cardio‐vascular health. CLNA isomers are naturally present in high concentrations in a large variety of seed oils but can also be produced in vitro by strains of lactobacilli and bifidobactena through the activity of the enzyme linoleic acid isomerase on α‐linolenic acid. In this review, we will address the possible therapeutic roles that CLNA may play in a number of conditions afflicting Western society and the mechanisms through which this activity is mediated.
Dynamic Analysis of Phorbol Esters in the Manufacturing Process of Fatty Acid Methyl Esters from Jatropha curcas Seed Oil
Authors: Ichihashi Kosuke , Yuki Dai , Kurokawa Hiroshi , Igarashi Akinori , Yajima Toshio , Fujiwara Masami , Maeno Katsuhiro , Sekiguchi Shizuo , Iwata Mitsuo , Nishino Hoyoku
Published: December 2010

Jatropha curcas seed oil, which is unsuitable as an edible oil but has received attention as a novel vegetable fat and oil resource, contains tumor‐promoting phorbol esters. Currently, six types of derivatives of 12‐deoxy‐16‐hydroxyphorbol (DHPEs) in J. curcas oil have been identified, and their toxicological safety for humans is being discussed. However, it is reported that most DHPEs disappear during the transesterification process. We investigated the dynamics of phorbol esters in the manufacturing process of fatty acid methyl esters from J. curcas seed oil. With the assumption that the precursor ion was the fragment ion (m/z = 311) from the frame unit of phorbol esters and their derivatives, we developed an LC–MS method for detecting the product ion (m/z = 165), which was obtained by cleavage of the fragment ion. The derivatives generated from the structural changes of the phorbol esters existed in fractions of glycerine–water in the manufacturing process; however, phorbol esters and their derivatives were not detected in the fatty acid methyl esters that were produced via a high‐vacuum distillation process. Investigation into the dynamics of phorbol esters confirmed that the contents of phorbol esters, including DHPEs, in the fatty acid methyl esters were under detection limits.
A new pelvic rod system for the surgical correction and fixation of pelvic obliquity in pediatric neuromuscular scoliosis
Authors: Chechik Ofir , Fishkin Michael , Wientroub Shlomo , Ovadia Dror
Published: December 2010

Purpose

To describe surgical outcomes using the new device in pediatric neuromuscular scoliosis.

Methods

All patients with neuromuscular disorders requiring surgery with pelvic fixation for the correction of scoliosis in the period 2002–2009 were operated by the new pelvic rod fixation device. Coronal and sagittal alignment before and after surgery until the latest follow-up were evaluated by standard X-rays. Intraoperative and postoperative complications were recorded.

Results

All 18 study patients (mean age at surgery 15 years, range 10–27) achieved solid fusion at a mean follow-up of 41 months. The coronal Cobb angle improved from 82° ± 31° (range 36–168) to 33° ± 25° at the last follow-up (range 9–95 months) ( P < 0.0001). Pelvic obliquity improved from 19° ± 6° (range 10–30) to 5° ± 5° (range 0–14) ( P < 0.0001). Early complications included pneumonia, urinary tract infection, disseminated intravascular coagulation (DIC), and hypovolemic shock. Three patients required debriding and received prolonged antimicrobial therapy for deep wound infection (none required implant removal). At the latest follow-up, no patient complained of lumbar pain or worsening of ambulatory status or level of activity.

Conclusion

Surgery employing the new pelvic rod fixation device allowed solid fusion and fixation with significant correction of multiplanar deformity, but the complication rate was high.
Death investigation systems and disease surveillance
Authors: McGOWAN C. R. , VIENS A. M.
Published: December 2010

Medico-legal death investigation systems have the potential to play an important role in disease surveillance. While these systems are in place to serve a public function, the degree to which they are independent of central government can vary depending on jurisdiction. How these systems use this independence may present problems for public health initiatives, as it allows death investigators to decline to participate in government-led surveillance regardless of how critical the studies may be to public health and safety. A recent illustration of this problem in the UK is examined, as well as general lessons for removing impediments to death investigation systems participating in public health research.
SOUTH SIDE BLUES: AN ORAL HISTORY OF THE CHICAGO SCHOOL
Authors: FREEDMAN CRAIG
Published: December 2010

Oral history has always held a rather ambiguous position within the study of economics. While widely read and enjoyed, such interviews are secretly scorned, dismissed as merely a lightweight diversion. Yet, to conduct revealing and insightful work of this type is difficult, requiring a firm grasp of economics, especially individual contributions to the discipline. This article examines my own attempts to come to grips with the methodology and ideology of the Chicago School through a series of conversations with some nineteen of George Stigler’s contemporaries. Oral history, if skillfully conducted, can prove to be one of the more useful tools in recapturing and understanding the past history of economics as a fiercely fought over discipline.
RULES FOR SUBATOMIC DERIVATION
Authors: WIĘCKOWSKI BARTOSZ
Published: December 2010

In proof-theoretic semantics the meaning of an atomic sentence is usually determined by a set of derivations in an atomic system which contain that sentence as a conclusion (see, in particular, Prawitz, 1971, 1973). The paper critically discusses this standard approach and suggests an alternative account which proceeds in terms of subatomic introduction and elimination rules for atomic sentences. A simple subatomic normal form theorem by which this account of the semantics of atomic sentences and the terms from which they are composed is underpinned, shows moreover that the proof-theoretic analysis of first-order logic can be pursued also beneath the atomic level.
Large offset monochromators at PETRA III
Authors: Horbach J. , Degenhardt M. , Hahn U. , Heuer J. , Peters H. B. , Schulte-Schrepping H. , Donat A. , Lüdecke H.
Published: December 2010

For the beamlines of the new synchrotron radiation source PETRA III, fixed-exit double crystal monochromators with specific features were developed. To achieve a compact arrangement of the canted undulator beamlines at Sectors 2, 4 and 6, it is necessary to shift one of the two beamlines in vertical direction. This is done by so-called large offset monochromators. Two of these monochromators (LOM500 and Mono-P06) accept the white beam and are therefore cooled with liquid nitrogen. The third one accepts a monochromatic beam and has no cooling system. The challenge with this device (LOM1250) is the large offset of the beam by 1.25 m. The energy range in combination with the large vertical beam offset demands for a relative crystal movement of roughly 3 m along the beam direction. This is implemented by translating each crystal by up to 1.5 m. It is equipped with a visible laser-based stabilization which allows compensating thermal drift of the mechanical components involved in the positioning of the crystals. With this novel approach the X-ray beam is not attenuated by beam position monitors.
Horizontal structure of sporadic E layer observed with a rocket‐borne magnesium ion imager
Authors: Kurihara J. , Koizumi‐Kurihara Y. , Iwagami N. , Suzuki T. , Kumamoto A. , Ono T. , Nakamura M. , Ishii M. , Matsuoka A. , Ishisaka K. , Abe T. , Nozawa S.
Published: December 2010

To study the spatial structure of midlatitude sporadic E (Es) layers, the ultraviolet resonant scattering by magnesium ions (Mg+) in an Es layer was observed during the evening twilight with the Magnesium Ion Imager (MII) on the sounding rocket launched from the Uchinoura Space Center in Kagoshima, Japan. The in situ electron density measured by an onboard impedance probe showed that the Es layer was located at an altitude of 100 km during both the ascent and descent of the flight. Simultaneous observation with a ground‐based ionosonde at Yamagawa identified the signature of horizontally “patchy” structures in the Es layer. The MII successfully scanned the horizontal Mg+ density perturbations in the Es layer and found that they had patchy and frontal structures. The horizontal scale and alignment of the observed frontal structure is generally consistent with a proposed theory. To our knowledge, this is the first observation of the two‐dimensional horizontal structure of Mg+ in an Es layer.
Transport driven by eddy momentum fluxes in the Gulf Stream Extension region
Authors: Greatbatch R. J. , Zhai X. , Claus M. , Czeschel L. , Rath W.
Published: December 2010

The importance of the Gulf Stream Extension region in climate and seasonal prediction research is being increasingly recognised. Here we use satellite‐derived eddy momentum fluxes to drive a shallow water model for the North Atlantic Ocean that includes the realistic ocean bottom topography. The results show that the eddy momentum fluxes can drive significant transport, sufficient to explain the observed increase in transport of the Gulf Stream following its separation from the coast at Cape Hatteras, as well as the observed recirculation gyres. The model also captures recirculating gyres seen in the mean sea surface height field within the North Atlantic Current system east of the Grand Banks of Newfoundland, including a representation of the Mann Eddy.
Mechanics of pressure solution seam growth and evolution
Authors: Zhou Xiaoxian , Aydin Atilla
Published: December 2010

Pressure solution seams (PSSs) can be idealized as localized volume reduction structures (LVRSs) in terms of their mechanics. Previous mechanical analyses of LVRSs, including compaction bands, showed that the normal stresses at the tips of LVRSs are compressive and significantly amplified with respect to the remote stresses, whereas on the flanks they are slightly reduced. These results can be used to rationalize the in‐plane growth of PSSs for a certain distance, however, based on these stress conditions alone, it is not possible to explain the widening and transverse coalescence of PSSs. In this study, based on laboratory and field observations that the PSS surfaces are extremely rough, we introduced asperities with triangular, semicircular, and rectangular geometries on the flanks of the LVRSs into our mechanical model to see if these asperities can raise stresses in these locations, which may rationalize the transverse growth of PSSs. It is found that these asperities can produce strong stress perturbations on the LVRS flanks thereby inducing a significant increase in the compressive normal stresses. In addition, to account for the rate factor of the pressure solution process, a creep law was adopted to simulate growth and coalescence of the LVRSs. Using the calculated normal compressive stresses and volumetric plastic strains as proxy for the growth, we show that (1) a single LVRS is able to grow both laterally and transversely for a short distance and (2) two in‐plane aligned neighboring LVRSs with a short distance between the adjacent tips and two parallel echelon and overlapped LVRSs with a small spacing may be able to link and coalesce to form a longer and wider LVRS, respectively. The influences of the LVRS geometric configurations, the material properties within the LVRSs, and the distance and spacing of the aligned in‐plane, echelon, and overlapping neighboring parallel LVRSs on the growth and coalescence of the LVRSs are investigated and their implications specifically for the PSSs are also discussed.
Long‐term versus short‐term deformation processes at Tenerife (Canary Islands)
Authors: Tizzani Pietro , Manconi Andrea , Zeni Giovanni , Pepe Antonio , Manzo Mariarosaria , Camacho Antonio , Fernández Jose
Published: December 2010

Several geophysical investigations have identified that the Tenerife volcanic complex is affected by crustal deformation processes occurring at timescales of millions of years. Recently, space‐based geodetic observations have also detected a short‐term surface deformation, characterized by a broad subsidence pattern with maximum ground velocities of about 4 mm yr−1. For the purpose of investigating the relationship between these long‐term and short‐term deformation processes, we performed an advanced fluid dynamic analysis (FDA). We first carried out a standard dimensionless FDA to discriminate the deformation style of Tenerife and found that, at million year timescales, basement flexure mainly controls its long‐term structural evolution. Secondly, to highlight the driving forces of the short‐term deformation process, we simulated a numerical FDA based on finite element models that include topography as well as vertical and lateral material heterogeneities. Our results show that the recent surface deformation is mainly caused by a progressive sagging of the denser (less viscous) core of the island onto the weaker (but more viscous) lithosphere. Moreover, over periods comparable to the hypothesized age of loading of the oceanic crust beneath Tenerife, this tendency would result in a total flexure of about 3–4 km, which is in agreement with independent estimations based on geophysical analyses. Our study shows that a unitary physical model may explain both the deformation recorded in deep geological structures and the current active ground deformation processes occurring at the Tenerife volcano.
Response of Norwegian Sea temperature to solar forcing since 1000 A.D.
Authors: Sejrup H. P. , Lehman S. J. , Haflidason H. , Noone D. , Muscheler R. , Berstad I. M. , Andrews J. T.
Published: December 2010

We report on a 1000 year long oxygen isotope record in sediments of the eastern Norwegian Sea which, we argue, represents the temperature and transport of warm Atlantic waters entering the Nordic Sea basin via the North Atlantic Drift and the large‐scale Meridional Overturning Circulation. The single‐sample resolution of the record is 2.5–10 years and age control is provided by 210Pb and 137Cs dating, identification of historic tephra, and a 14C “wiggle‐match” dating method in which the surface reservoir 14C age in the past is constrained rather than assumed, thereby eliminating a large source of chronological uncertainty. The oxygen isotope results indicate decade‐ to century‐scale temperature variations of 1–2°C in the shallow (∼50 m deep) subsurface which we find to be strongly correlated with various proxies of past solar activity. The correlations are synchronous to within the timescale uncertainties of the ocean and solar proxy records, which vary among the records and in time with a range of about 5–30 years. The observed ocean temperature response is larger than expected based on simple thermodynamic considerations, indicating that there is dynamical response of the high‐latitude ocean to the Sun. Correlations of our results with a gridded temperature reconstruction for Europe are greater in central Europe than in coastal regions, suggesting that the temperature and transport of warm Atlantic waters entering the Nordic Basin and the pattern of temperature variability over Europe are both the proximate responses to a change in the atmospheric circulation, consistent with a forced shift in the primary modes of high‐latitude atmospheric variability.
Estimation of total lightning from various storm parameters: A cloud‐resolving model study
Authors: Barthe Christelle , Deierling Wiebke , Barth Mary C.
Published: December 2010

Because explicit prediction of the electrical activity in storms is computationally expensive and the processes are still poorly understood, an attractive way to predict lightning flash rates in numerical models is to rely on correlations between the flash rate and available model parameters. Predicted flash rates can be used for applications such as the parameterization to infer lightning‐produced nitrogen oxides. In this study, the potential for six model parameters (precipitation ice mass, ice water path, ice mass flux product, updraft volume, maximum vertical velocity, and cloud top height) to predict lightning rate has been investigated in a cloud‐resolving model framework. The Weather Research and Forecasting model (WRF) is used to simulate two different storms: the 10 July 1996 severe storm that occurred over the High Plains and the 13 July 2005 airmass thunderstorm near Huntsville, Alabama. It is shown that the WRF model reproduces the structure of the two storms. Results show that the maximum updraft velocity gives a good flash rate proxy for the severe storm. The ice mass flux product and precipitation ice mass can reproduce the flash rate trend but not the magnitude. The flash rate estimated from the cloud top height does not match the observed flash rate trend and value of the severe storm, but is in good agreement for the airmass thunderstorm. The ice water path predicts flash rate fairly well for the severe storm, but overpredicts it for the airmass thunderstorm. The updraft volume predicts flash rate poorly for both storms.
Land surface modeling inside the Biosphere 2 tropical rain forest biome
Authors: Rosolem Rafael , Shuttleworth W. James , Zeng Xubin , Saleska Scott R. , Huxman Travis E.
Published: December 2010

Tropical rain forests contribute substantially to regional and global energy, water, and carbon exchanges between the land surface and the atmosphere, and better understanding of the mechanisms of vegetation response to different environmental stresses is needed. The Biosphere 2 facility provides an opportunity to link laboratory‐scale and plot‐scale studies in a controllable environment. We compiled a consistent quality‐controlled time series of climate data from Biosphere 2 and used it to drive the Simple Biosphere model (SiB3) to test how well it represented the behavior of soils and vegetation inside the tropical rain forest biome of Biosphere 2 (B2‐TRF). We found that soil respiration parameterization in SiB3 was not suitable for use in B2‐TRF, so several alternative parameterizations were tested. None gave outstanding results, but a modified version of the parameterization originally proposed for SiB3 gave the best results. With this modification, SiB3 well simulated the observed net ecosystem exchange in B2‐TRF but, significantly, only after additionally modifying parameters describing the thermal tolerance of plants so that photosynthetic capacity was reduced on average but maintained to higher temperatures. This implies either that tropical rain forest species can acclimate to higher temperatures than allowed for by vegetation models or that the plant community assembly in B2‐TRF has shifted to allow continued functioning at higher temperatures, and plants in natural ecosystems could also. In either case, this suggests that the Amazon rain forest may be more resilient to climate change than hitherto thought.
Relative impact of anthropogenic modifications versus climate change on the natural flow regimes of rivers in the Northern Rocky Mountains, United States
Authors: Arrigoni Alicia S. , Greenwood Mark C. , Moore Johnnie N.
Published: December 2010

We studied discharge data from stream gauges located in natural and anthropogenically modified river basins of the Northern Rocky Mountains over 59 years. We applied linear and nonlinear models to the data to determine what, if any, alterations have occurred in the annual flow regimes. By comparing the different results from the natural and anthropogenically modified river basins, we were able to distinguish the impacts that climate change and anthropogenic modifications have had on flow regimes in the Northern Rocky Mountains over the period of record. We found that regional climate change has not significantly altered the natural flow regimes. However, we did find an underlying cyclical pattern in the total amount of annual discharge in both the natural and anthropogenically modified river basins. This suggests a strong link between the quantity of runoff and some kind of hydroclimatologic cycle. Conversely, direct basin anthropogenic modifications such as damming, irrigation, and urbanization have caused a decrease in the difference between the minimum and maximum annual discharges and a decrease in the daily variations of flows across the Northern Rocky Mountains. In general, direct anthropogenic modifications of the river basins have altered the flow regimes to a much greater extent than climate change.
Protective Role for Type 4 Metabotropic Glutamate Receptors against Ischemic Brain Damage
Authors: Moyanova Slavianka G , Mastroiacovo Federica , Kortenska Lidia V , Mitreva Rumiana G , Fardone Erminia , Santolini Ines , Sobrado Mónica , Battaglia Giuseppe , Bruno Valeria , Nicoletti Ferdinando , Ngomba Richard T
Published: December 2010

We examined the influence of type 4 metabotropic glutamate (mGlu4) receptors on ischemic brain damage using the permanent middle cerebral artery occlusion (MCAO) model in mice and the endothelin-1 (Et-1) model of transient focal ischemia in rats. Mice lacking mGlu4 receptors showed a 25% to 30% increase in infarct volume after MCAO as compared with wild-type littermates. In normal mice, systemic injection of the selective mGlu4 receptor enhancer, N-phenyl-7-(hydroxyimino)cyclopropa[b]chromen-1a-caboxamide (PHCCC; 10 mg/kg, subcutaneous, administered once 30 minutes before MCAO), reduced the extent of ischemic brain damage by 35% to 45%. The drug was inactive in mGlu4 receptor knockout mice. In the Et-1 model, PHCCC administered only once 20 minutes after ischemia reduced the infarct volume to a larger extent in the caudate/putamen than in the cerebral cortex. Ischemic rats treated with PHCCC showed a faster recovery of neuronal function, as shown by electrocorticographic recording and by a battery of specific tests, which assess sensorimotor deficits. These data indicate that activation of mGlu4 receptors limit the development of brain damage after permanent or transient focal ischemia. These findings are promising because selective mGlu4 receptor enhancers are under clinical development for the treatment of Parkinson's disease and other central nervous system disorders.
Constraint-Guided Workflow Composition Based on the EDAM Ontology
Authors: Lamprecht Anna-Lena , Naujokat Stefan , Steffen Bernhard , Margaria Tiziana
Published: December 2010

Methods for the automatic composition of services into executable workflows need detailed knowledge about the application domain, in particular about the available services and their behavior in terms of input/output data descriptions. In this paper we discuss how the EMBRACE data and methods ontology (EDAM) can be used as background knowledge for the composition of bioinformatics workflows. We show by means of a small example domain that the EDAM knowledge facilitates finding possible workflows, but that additional knowledge is required to guide the search towards actually adequate solutions. We illustrate how the ability to flexibly formulate domain-specific and problem-specific constraints supports the workflow development process.
A linked electron pair functional
Authors: Knowles Peter J. , Cooper Bridgette
Published: December 2010

A modification of the variational configuration interaction functional in the first-order interacting space for molecular electronic structure is presented. The modified functional is a fully linked expression that by construction is extensive and invariant to transformations of the underlying orbital basis and is exact for an ensemble of separated two-electron subsystems. In addition, an approximation to variational coupled cluster is generated through truncation of the exponential cluster operator. When combined, these methods demonstrate accuracy that exceeds that of the standard coupled-cluster method, in particular in situations where the reference Slater determinant is not a good approximation.
Solution processed polymer light-emitting diodes utilizing a ZnO/organic ionic interlayer with Al cathode
Authors: Youn Hongseok , Yang Minyang
Published: December 2010

This letter reports polymer light-emitting diodes that employ a soluble zinc oxide (ZnO) nanoparticle (NP) and organic ionic interlayer as an electron-injection layer exhibits remarkable enhancement of device performance despite aluminum cathode. The ionic solution infiltrated into ZnO NP layer, which contains poly(ethylene oxide) and tetra-n-butylammonium tetrafluoborate, significantly lowers the large electron-injection barrier by forming a permanent interfacial dipole. The polymer, phenyl substituted poly(para-phenylene vinylene) known as “Super Yellow,” yellow light-emitting diodes employing the ZnO NP and ionic interlayer show a maximum efficiency of 6.3 cd/A at a 1209 cd/m2 and 5.4 V. The maximum brightness of the device reached 24 000 cd/m2 at 9 V.
Orientation of colloidally suspended LiNbO3 nanocrystals in externally applied electric fields
Authors: Schütze D. , Knabe B. , Ackermann M. , Buse K.
Published: December 2010

Electric fields are applied to lithium niobate nanoparticles of 41 nm radius colloidally suspended in heptane. Interferometric measurements of field-induced refractive index changes show that the particle orientation is dominated by induced dipole moments. There are indications that a permanent dipole moment of the nanoparticles of 10−26 C m along their crystallographic c-axis is present as well. An electric field of 2 kV/mm is sufficient to align 80% of the particles, such that the angle between their c-axis and the applied electric field direction is less than 70°, making applications of such a liquid with electrically controlled optical properties feasible.
Charge accumulation dynamics in organic thin film transistors
Authors: Chen X. Y. , Zhu H. , Wang S. D.
Published: December 2010

We have developed a transient current model to quantitatively describe the charge accumulation dynamics in organic thin film transistors. This model indicates that the charge accumulation process is faster at higher gate bias and/or higher field-effect mobility, and the experimental results are consistent with the theoretical expectations. A strong gate bias dependence of the field-effect mobility is observed, which suggests that the charge traps in the charge accumulation layer may limit the device performance not only at steady state but also at transient state.
Superconducting microfabricated ion traps
Authors: Wang Shannon X. , Ge Yufei , Labaziewicz Jaroslaw , Dauler Eric , Berggren Karl , Chuang Isaac L.
Published: December 2010

We fabricate superconducting ion traps with niobium and niobium nitride and trap single S88r ions at cryogenic temperatures. The superconducting transition is verified and characterized by measuring the resistance and critical current using a four-wire measurement on the trap structure, and observing change in the rf reflection. The lowest observed heating rate is 2.1(3) quanta/s at 800 kHz at 6 K and shows no significant change across the superconducting transition, suggesting that anomalous heating is primarily caused by noise sources on the surface. This demonstration of superconducting ion traps opens up possibilities for integrating trapped ions and molecular ions with superconducting devices.
Optimization of branched resonant nanostructures illuminated by a strongly focused beam
Authors: Elezgaray Juan , Berguiga Lotfi , Argoul Françoise
Published: December 2010

In the design of nanostructures to perform single molecule surface enhanced Raman spectroscopy (SM-SERS), metallic structures with very narrow gaps (<1 nm) have been shown to contain regions with electric fields compatible with SM-SERS. However, this geometrical condition does not allow many biomolecules to reach the hot-spot regions. Here, we show that optimized branched structures formed by appropriate arrangements of gold nanoparticles with gaps ≥2 nm display field enhancements >102, compatible with SM-SERS.
Energy Services for the Urban Poor: NGO Participation in Slum Electrification in India
Authors: Baruah Bipasha
Published: December 2010

Some 40% of the world's urban poor—living predominantly in informal settlements—lack access to legal electricity. Urban upgradation programmes, if they exist, prioritize water supply over electrification since water is nonsubstitutable and more essential for sustaining human life. Illegal electricity—albeit unreliable, expensive and dangerous—is also already widely available in informal settlements. I share the experiences of the Self-Employed Women's Association and Saath—two nongovermental organizations (NGOs) based in India—of participating in a multiple-stakeholder propoor electrification programme. By 2008 close to 100 000 homes had been electrified in the city of Ahmedabad and the programme is currently being replicated in smaller cities in Gujarat and in the neighbouring state of Rajasthan. I use academic literature on urban infrastructure provision and politics, project reports and evaluations, pricing surveys, and interviews with electricity utility and NGO staff to analyze the programme for its impacts upon access, tariffs, consumption patterns, quality of service, and security of land tenure. The findings indicate that NGOs can be very effective as intermediaries between utilities, municipalities, and urban poor communities. However, scaling up such programmes will require strong state involvement in developing a policy framework to facilitate NGO participation in the design and implementation of propoor electrification activities, and in the energy reform process in general.
Development of a software model to estimate daily greenhouse gas emissions of pasture-fed ruminant farming systems
Authors: Sise J. A. , Kerslake J. I. , Oliver M. J. , Glennie S. , Butler D. , Behrent M. , Fennessy P. F. , Campbell A. W.
Published: December 2010

A software model has been developed to estimate greenhouse gas emissions of pasture-fed ruminant farming systems. The model estimates on-farm emissions associated with livestock (sheep and beef), fertiliser, petrol, diesel and electricity. Carbon sequestration from native and exotic forestry is then included to produce an on-farm carbon footprint, in the form of carbon dioxide equivalents. This paper describes the livestock model, which has been designed to record the movement of animals within individual farm units according to defined livestock classes. Allowances are made for unrecorded deaths, by estimating the number of animals missing within a defined time period and spreading the deaths according to expected seasonal variation in mortality. The enteric methane and nitrous oxide emissions are predicted using a combination of customised growth and lactation curves, and internationally recognised formulae to predict nutrient energy requirements. Customised growth and lactation curves allow estimation of liveweights and energy requirements associated with maintenance, growth, pregnancy and lactation on a daily basis. Daily estimation of emissions reduces errors introduced by monthly or seasonal averaging of livestock numbers and liveweights. The model has been developed into a commercial application (Alliance Group hoofprint) for use by New Zealand sheep and beef farmers, and could be adapted for other international livestock farming operations.
A Socio-Phonetic Investigation of Rhotics in Persian
Authors: Rafat Yasaman
Published: December 2010

This paper fills in the gap in the literature by providing an acoustic analysis of rhotics in Persian and considers the social variables gender and register. Through the acoustic analysis of 807 tokens, it demonstrates that that there are a number of rhotic variants in Persian in different positions in the word and finds evidence of degemination in coda position, against previous accounts. Furthermore, it suggests that on the one hand, Tehrani-Persian speaking men and women's rhotic production patterns with those of Arabic societies as men favor rhotics with more complex articulations. On the other hand it questions whether the behavior of Tehrani-Persian speaking men and women conforms to established sociolinguistic norms regarding prestige and gender.
Studying Isma‘ili Texts in Eleventh-Century Shiraz: al-Mu'ayyad and the “Conversion” of the BuyidAmirAbu Kalijar
Authors: Alexandrin Elizabeth R.
Published: December 2010

As a key primary source for the history of the eleventh-century Isma‘ili majlis, the Fatimid chief missionary al-Mu'ayyad fi al-Din al-Shirazi's autobiographical Sira offers a prime opportunity to consider the application of centralizing features of the Fatimid state in eleventh-century Buyid Shiraz. Previous studies on the Fatimid majlis have raised questions about an Isma‘ili core curriculum as well as the intended audience/s of Fatimid da‘wa teachings. This article situates al-Mu'ayyad's memoir in the broader context of the Persian and Arabic historiographical traditions in order to provide new insights into the transmission of Isma‘ili doctrines in different social settings outside of Fatimid Cairo. It concludes that Abu Kalijar's study sessions with al-Mu'ayyad suggest that Qadi al-Nu‘man's Kitab Da‘a'im al-Islam was used as a core text for introducing some of the main principles of Fatimid religio-political rule in addition to Isma‘ili doctrines to non-Isma‘ili audiences.
The Confessions of Dolgoruki: Fiction and Masternarrative in Twentieth-Century Iran
Authors: Yazdani Mina
Published: December 2010

This paper is an in-depth study ofThe Confessions of Dolgoruki, the purported memoirs of a nineteenth-century Russian ambassador to Iran, long adduced as a document proving the claim that the Bahā'īs of Iran are spies of foreign powers. It unearths several early versions of the text, contextualizes the creation ofThe Confessions, exams the zeitgeist that produced it, and tracks the changes the text went through as the dominant socio-political discourse changed over time. In discussing the range of reactionsThe Confessionsprovoked, this paper traces the intriguing path through which this text created the masternarrative of Bahā'ī espionage. Finally, a hypothesis regarding the identity of the original creator of the text is advanced.
Teacher identities in a research‐led institution: In the ascendancy or on the retreat?
Authors: Skelton Alan
Published: December 2010

This article explores how teacher identities are negotiated within a research‐led institution in the UK. Over the last decade a wide range of initiatives has been introduced to promote teaching in higher education. Research has shown, however, that these initiatives have met with limited success in terms of changing predominant values and culture. This article focuses on the formation of teacher identities in a research‐led institution—a setting that offers significant resistance to cultural change. It draws on in‐depth interviews with 11 members of university staff who want to improve their teaching to explore the under‐researched notion of ‘teacher identity’. The data revealed a complex picture. Some people are pursuing a teaching identity with clear intent, drawing on personal values to inform their teaching and feeling relatively untroubled by external constraints. Others are committed to changing prevailing culture and attitudes. There are examples of significant ‘identity struggles’ as people attempt to juggle personal commitments to teaching with the realities of the research culture. The article identifies three main teacher identities: ‘teaching specialists’, ‘blended professionals’ and ‘researchers who teach’. Variation within and across these categories suggests that teacher identities cannot be read off simply from formal role descriptions.