bluuebunny/crossref_metadata_2025 huggingface dataset:
Implications of ignoring telemetry error on inference in wildlife resource use models
Authors: Montgomery Robert A. , Roloff Gary J. , Hoef Jay M. Ver
Published: May 2011

Global Positioning System (GPS) and very high frequency (VHF) telemetry data redefined the examination of wildlife resource use. Researchers collar animals, relocate those animals over time, and utilize the estimated locations to infer resource use and build predictive models. Precision of these estimated wildlife locations, however, influences the reliability of point‐based models with accuracy depending on the interaction between mean telemetry error and how habitat characteristics are mapped (categorical raster resolution and patch size). Telemetry data often foster the assumption that locational error can be ignored without biasing study results. We evaluated the effects of mean telemetry error and categorical raster resolution on the correct characterization of patch use when locational error is ignored. We found that our ability to accurately attribute patch type to an estimated telemetry location improved nonlinearly as patch size increased and mean telemetry error decreased. Furthermore, the exact shape of these relationships was directly influenced by categorical raster resolution. Accuracy ranged from 100% (200‐ha patch size, 1‐ to 5‐m telemetry error) to 46% (0.5‐ha patch size, 56‐ to 60‐m telemetry error) for 10 m resolution rasters. Accuracy ranged from 99% (200‐ha patch size, 1‐ to 5‐m telemetry error) to 57% (0.5‐ha patch size, 56‐ to 60‐m telemetry error) for 30‐m resolution rasters. When covariate rasters were less resolute (30 m vs. 10 m) estimates for the ignore technique were more accurate at smaller patch sizes. Hence, both fine resolution (10 m) covariate rasters and small patch sizes increased probability of patch misidentification. Our results help frame the scope of ecological inference made from point‐based wildlife resource use models. For instance, to make ecological inferences with 90% accuracy at small patch sizes (≤5 ha) mean telemetry error ≤5 m is required for 10‐m resolution categorical rasters. To achieve the same inference on 30‐m resolution categorical rasters, mean telemetry error ≤10 m is required. We encourage wildlife professionals creating point‐based models to assess whether reasonable estimates of resource use can be expected given their telemetry error, covariate raster resolution, and range of patch sizes. © 2011 The Wildlife Society.
Separation of asymmetric triacylglycerols into their enantiomers by recycle high‐performance liquid chromatography
Authors: Gotoh Naohiro , Wada Shun , Nagai Toshiharu
Published: May 2011

A recycle HPLC system equipped with a polysaccharide‐based chiral column was used for the enantiomeric separation of asymmetric triacylglycerols (TAGs). When the chiral columns were screened by the resolution of 1,2‐dipalmitoyl‐3‐oleoyl‐rac‐glycerol separation was achieved only with the cellulose tris‐ (3,5‐dimethylphenylcarbamate) chiral selector. The resolution of other TAG enantiomers was also examined, and 1,2‐dioleoyl‐3‐palmitoyl‐rac‐glycerol, 1,2‐dipalmitoyl‐3‐linoleoyl‐rac‐glycerol, 1,2‐dipalmitoyl‐3‐eicosapentaenoyl‐rac‐glycerol, 1,2‐dipalmitoyl‐3‐docosahexaenoyl‐rac‐glycerol, and 1,2‐docosahexaenoyl‐3‐palmitoyl‐rac‐glycerol were resolved into their respective enantiomers. However, neither 1,2‐dioleoyl‐3‐linoleoyl‐rac‐glycerol, consisting of only unsaturated fatty acids, nor 1,2‐dipalmitoyl‐3‐stearoyl‐rac‐glycerol, consisting of only saturated fatty acids, was resolved. In addition, 1,2‐eicosapentaenoyl‐3‐palmitoyl‐rac‐glycerol was not resolved clearly, even in the recycle runs. These results suggest that asymmetric TAGs having both a palmitic acid moiety and an unsaturated fatty acid moiety at the sn‐1 or sn‐3 positions might be resolved on a cellulose tris‐ (3,5‐dimethylphenylcarbamate) chiral column.
Promoter methylation of cyclin A1 is associated with human papillomavirus 16 induced head and neck squamous cell carcinoma independently of p53 mutation
Authors: Weiss Daniel , Basel Tuerker , Sachse Florian , Braeuninger Andreas , Rudack Claudia
Published: May 2011

Aberrant promoter methylation of specific genes and infection with human papillomavirus 16 (HPV16) are known risk factors for the development of Head and Neck Squamous Cell Carcinoma (HNSCC). Little knowledge exists on the interaction of HPV16 infection and promoter methylation in HNSCC. The promoter methylation status of 12 genes (TIMP3, CDH1, CDKN2A, DAPK1, transcription factor 21 (TCF21), CD44, MLH1, MGMT, RASSF1, cyclin A1 (CCNA1), LARS2, and CEBPA) was evaluated by methylation‐specific polymerase chain reaction in 55 primary HNSCC and 31 controls. The results were correlated with HPV16 status and clinicopathological characteristics. CCNA1 and p53 protein expression were additionally determined by immunohistochemistry and compared with p53 mutation status. Methylation of DAPK1 (P = 0.043), CCNA1 (P = 0.016) and TCF21 (P = 0.0005) was significantly more present in HNSCC than in controls. The genes TIMP3 (P = 0.018) and CCNA1 (P = 0.015) showed higher methylation frequency in HPV16 positive HNSCC compared to HPV16 negative tumors. CCNA1 methylation did not correlate with CCNA1 protein expression and p53 mutation, respectively. Methylation of TCF21 was associated with higher age (P = 0.044) and nicotine abuse (P = 0.035). Methylation of CCNA1 was significantly more present in females (P = 0.003). Methylation of TCF21 and CCNA1 are important risk factors for HNSCC development. CCNA1 methylation may play a crucial role in HPV16‐induced carcinogenesis of HNSCC independently of p53. © 2011 Wiley‐Liss, Inc.
TMKink: A method to predict transmembrane helix kinks
Authors: Meruelo Alejandro D. , Samish Ilan , Bowie James U.
Published: May 2011

A hallmark of membrane protein structure is the large number of distorted transmembrane helices. Because of the prevalence of bends, it is important to not only understand how they are generated but also to learn how to predict their occurrence. Here, we find that there are local sequence preferences in kinked helices, most notably a higher abundance of proline, which can be exploited to identify bends from local sequence information. A neural network predictor identifies over two‐thirds of all bends (sensitivity 0.70) with high reliability (specificity 0.89). It is likely that more structural data will allow for better helix distortion predictors with increased coverage in the future. The kink predictor, TMKink, is available at http://tmkinkpredictor.mbi.ucla.edu/.
Charged residues at protein interaction interfaces: Unexpected conservation and orchestrated divergence
Authors: Zhao Nan , Pang Bin , Shyu Chi‐Ren , Korkin Dmitry
Published: May 2011

Protein–protein interactions play an essential role in the functioning of cell. The importance of charged residues and their diverse role in protein–protein interactions have been well studied using experimental and computational methods. Often, charged residues located in protein interaction interfaces are conserved across the families of homologous proteins and protein complexes. However, on a large scale, it has been recently shown that charged residues are significantly less conserved than other residue types in protein interaction interfaces. The goal of this work is to understand the role of charged residues in the protein interaction interfaces through their conservation patterns. Here, we propose a simple approach where the structural conservation of the charged residue pairs is analyzed among the pairs of homologous binary complexes. Specifically, we determine a large set of homologous interactions using an interaction interface similarity measure and catalog the basic types of conservation patterns among the charged residue pairs. We find an unexpected conservation pattern, which we call the correlated reappearance, occurring among the pairs of homologous interfaces more frequently than the fully conserved pairs of charged residues. Furthermore, the analysis of the conservation patterns across different superkingdoms as well as structural classes of proteins has revealed that the correlated reappearance of charged residues is by far the most prevalent conservation pattern, often occurring more frequently than the unconserved charged residues. We discuss a possible role that the new conservation pattern may play in the long‐range electrostatic steering effect.
Probing the structure of membrane proteins with electron spin echo envelope modulation spectroscopy
Authors: Mayo Daniel , Zhou Andy , Sahu Indra , McCarrick Robert , Walton Parker , Ring Adam , Troxel Kaylee , Coey Aaron , Hawn Jaclyn , Emwas Abdul‐Hamid , Lorigan Gary A.
Published: May 2011

A new approach has been developed to probe the structural properties of membrane peptides and proteins using the pulsed electron paramagnetic resonance technique of electron spin echo envelope modulation (ESEEM) spectroscopy and the α‐helical M2δ subunit of the acetylcholine receptor incorporated into phospholipid bicelles. To demonstrate the practicality of this method, a cysteine‐mutated nitroxide spin label (SL) is positioned 1, 2, 3, and 4 residues away from a fully deuterated Val side chain (denoted i + 1 to i + 4). The characteristic periodicity of the α‐helical structure gives rise to a unique pattern in the ESEEM spectra. In the i + 1 and i + 2 samples, the 2H nuclei are too far away to be detected. However, with the 3.6 residue per turn pattern of an α‐helix, the i + 3 and i + 4 samples reveal a strong signal from the 2H nuclei of the Val side chain. Modeling studies verify these data suggesting that the closest 2H‐labeled Val to SL distance would in fact be expected in the i + 3 and i + 4 samples. This technique is very advantageous, because it provides pertinent qualitative structural information on an inherently difficult system like membrane proteins in a short period of time (minutes) with small amounts of protein (μg).
Quantification of extraprostatic perineural spread and its prognostic value in pT3a pN0 M0 R0 prostate cancer patients
Authors: Aumayr Klaus , Breitegger Michael , Mazal Peter R. , Koller Anke , Marberger Michael , Susani Martin , Haitel Andrea
Published: May 2011

BACKGROUND

The prognostic relevance of the amount of extraprostatic cancer spread in nerves in prostate cancer patients is not well established.

METHODS

Eighty‐eight patients were included in our study with pT3a pN0 M0 R0 prostate cancer treated with retropubic prostatectomy. Eighty‐seven of them showed perineural invasion, 54 were confined to the prostate, 33 showed cancer spread in extraprostatic nerves, which was quantified by counting each transverse section of nerves infiltrated by cancer in totally embedded specimens. Biochemical relapse was established by serum PSA levels of ≥0.2 ng/ml as well as PSA ≥ 0.4 ng/ml and higher according to the EAU guidelines.

RESULTS

Extraprostatic but not intraprostatic perineural infiltration was significantly more often found in tumors of higher Gleason score. Intraprostatic number of infiltrated nerves (NIN) correlated with extraprostatic NIN. There was no association between extraprostatic or intraprostatic NIN and Gleason score, lymphatic, or blood vessel invasion. Extraprostatic neural infiltration in ≤10 nerves extended relapse free survival in univariate analysis for PSA 0.2 and 0.4 ng/ml (P = 0.002 and P < 0.000001, respectively) and remained significant in multivariate analysis for PSA 0.4 ng/ml (P = 0.039).

CONCLUSIONS

High amount of extraprostatic NIN correlates with tumor progression and seems to be an independent prognostic parameter. Prostate 71:1790–1795, 2011. © 2011 Wiley Periodicals, Inc.
Pathological significance and predictive value for biochemical recurrence of c‐Fes expression in prostate cancer
Authors: Miyata Yasuyoshi , Watanabe Shin‐ichi , Matsuo Tomohiro , Hayashi Tomayoshi , Sakai Hideki , Xuan Jim W. , Greer Peter A. , Kanda Shigeru
Published: May 2011

BACKGROUND

c‐Fes is a proto–oncogene encoded non‐receptor protein–tyrosine kinase (PTK). However, genetic studies have indicated that it has anti‐tumorigenic effects in certain cancers. The pathological and clinical significance of c‐Fes in prostate cancer are unknown.

METHODS

Expression of c‐Fes was evaluated in normal glands, prostatic intraepithelial neoplasia (PIN), cancer cells in tissues of knock‐in mouse adenocarcinoma prostate (KIMAP) model, and prostate cancer patients free of metastasis. Expression of c‐Fes was analyzed by immunohistochemistry, and quantified by using the immunoreactivity score (IRS) (staining intensity × percentage of positive cells). Relationships between c‐Fes expression and pT stage, Gleason's score (GS), and biochemical recurrence in patients who underwent radical surgery were also investigated.

RESULTS

In KIMAP, the percentage in normal glands, PIN and cancer cells positive for c‐Fes expression were 0 (0/7), 25.0 (2/8), and 100% (7/7), respectively. In human tissues, c‐Fes expression was also significantly higher in cancer cells than in normal cells and PIN, and it correlated with pT stage (P < 0.001) and GS (P = 0.047). Multivariate analysis showed that c‐Fes expression was an independent predictor of poor outcome poor prognosis (hazard ratio = 3.21, 95% confidence interval = 1.11–9.37, P = 0.032).

CONCLUSION

The results suggested that c‐Fes expression is a useful predictor of biochemical recurrence after radical surgery. The results also suggested that c‐Fes is a potentially useful therapeutic target in prostate cancer and a predictor of biochemical recurrence after radical prostatectomy. Prostate 72:201–208, 2012. © 2011 Wiley Periodicals, Inc.
Functional surfaces in heterogeneous catalysis: A short review
Authors: Rosenthal Dirk
Published: May 2011

Heterogeneous catalysis and functional surfaces are intimately connected. Surface functionalities mediate the catalytic reactions. However, the surface must fulfil several requirements: adsorption of the reactants on the surface must be energetically favoured (but reversible), the surface functionalities must enhance the dissociation of chemical bonds in the reactant and the formation of new ones which will lead to the reaction's product(s), and finally the product(s) must be able to desorb and leave the surface. It was shown that for the ammonia synthesis on ruthenium single crystalline surfaces, both the geometric and electronic functionalities of step edges are crucial to dissociate nitrogen. Another well‐investigated reaction is the catalytic oxidation of carbon monoxide over platinum and oxidized ruthenium. For both metals, the surface is dynamic, which leads to a change in its functionalities during reaction. These few examples of simple reactions already show the complexity of the necessary surface functionalities for heterogeneous catalysis and the problems connected with the understanding of rather simple reaction mechanisms. The key objective in catalysis research consists in tailoring the geometric and electronic properties of catalysts depending on the target reactions. One attempt in this direction is the investigation of binary alloys and, more recently, of intermetallic compounds. Here, the adsorption properties of the reactants could be drastically changed. A completely different way of changing adsorption properties also exists for semiconductor surfaces: the direct application of electric fields leads to a change of charge carriers near the surface – the electro‐adsorptive effect (EAE).
Spectral phase interference: A tool for the study of adsorption processes on solid surfaces
Authors: Kusterer Jan , Bakowsky Udo , Keusgen Michael
Published: May 2011

Spectral phase interference (SPI) has attracted considerable attention during last years as method for biomolecular interaction analysis (BIA). The advantages of this method are real time measurements independently from the refraction index of the investigated solution. Therefore, this method was applied for evaluating the influence of mouth rinsing solutions like chlorhexidine digluconate (CHX)‐solutions on the pellicle formation upon a tooth model. The tooth model was a based glass chip, type ‘K0’. The surface of this activated glass chip is comparable to the surface of the enamel of a tooth. After surface activation, saliva was applied in order to deposit a pellicle layer. The pellicle is the primary protein layer formed on the surface of a tooth. This layer has the function to prevent a direct contact of bacteria with the tooth surface. As a disadvantage, this layer is the docking point and primary nutrition reservoir for bacteria forming the plaque. Analysing the interaction of this bio layer with mouth rinsing solutions is essential to evaluate effects on the formation of plaque. In this investigation, evidences for positive effects of CHX‐solutions and amino fluorides on the formation of the pellicle have been found. Treatment with these solutions resulted in a dose dependent enhanced thickness of the pellicle. It can be assumed, that these modified pellicle layers are more resistant against bacteria attack.
Effect of magnetic field on the capacitance of the La0.5Ca0.5MnO3‐based heterojunction
Authors: Lu H. X. , Sun J. R. , Zhao J. L. , Shen B. G.
Published: May 2011

Effects of interface decoration and ac frequency, under which the impedance is measured, on the magnetoelectric property have been experimentally studied for the heterojunctions of La0.5Ca0.5MnO3/SrTiO3:Nb and La0.5Ca0.5MnO3/LaMnO3(3nm)/SrTiO3:Nb. It is found that the impedance of the junction can be well described by an effective circuit of two R–C sub‐circuits in series well above 100 K. Magnetocapacitance emerges and develops as temperature decreases, and shows a strong frequency‐dependent character. The maximal magnetocapacitance, under a field of 5 T, is ∼30 and ∼35% with and without the buffer layer, respectively. The incorporation of the LaMnO3 layer shifts the upper temperature limit for significant magnetocapacitance from ∼120 to ∼200 K. Shrinkage of the depletion layer of the junction under magnetic field may be a main reason for the magnetoelectric effect observed here.
Pressure effects in PrT2B2C (T = Co, Ni, Pt): Applied and chemical pressure
Authors: Falconi R. , Durán A. , Núñez‐Regueiro M. , Escudero R.
Published: May 2011

High pressure electrical resistivity ρab measurements on intermetallic Pr(Co, Ni, Pt)2B2C compounds were performed down to 2 K. At ambient pressure the $\rho _{ab} (T)$ curves for the non‐superconducting Pr(Co, Ni)2B2C compounds exhibit magnetic correlations at about 10 and 4 K, respectively. At low temperatures, PrCo2B2C shows a large spin‐dependent electron scattering in comparison to PrNi2B2C. Under applied pressure, the magnetic scattering tends to be suppressed more effectively in PrCo2B2C than in PrNi2B2C. The low‐temperature behavior of $\rho _{ab} (T,P)$ for PrNi2B2C and PrCo2B2C suggests a spin fluctuation mechanism. On the other hand, the PrPt2B2C compound shows superconductivity at about 6 K and under pressure its superconducting transition temperature tends to be degraded at a rate ${\rm d}T_{{\rm c}} /{\rm d}P = {-} 0.34\;{\rm K/GPa}$, as expected in compounds with transition metals. The experimental results in Co‐, Ni‐, and Pt‐based compounds are analyzed from the point of view of the external and chemical internal pressure effects.
Ultrafast magnetization dynamics in the half‐metallic Heusler alloy Co2Cr0.6Fe0.4Al
Authors: Wüstenberg Jan‐Peter , Steil Daniel , Alebrand Sabine , Roth Tobias , Aeschlimann Martin , Cinchetti Mirko
Published: May 2011

Ultrafast demagnetization upon excitation with intense laser pulses has been observed for a variety of ferromagnetic materials. In half‐metals, long demagnetization times are expected due to the band gap for one spin direction. We have investigated the theoretically half‐metallic Heusler alloy Co2Cr0.6Fe0.4Al (CCFA), using the time‐resolved magnetooptical Kerr effect. A demagnetization time in the range of typical transition metal ferromagnets with lower spin polarization has been found, while magnetization recovery proceeds on a slower time scale. The results are discussed in the context of recent models and experimental results. We propose that for Heusler alloys the initial stage of recovery could be a better measure for the spin polarization than the demagnetization time. A simple estimate leads to a bulk spin polarization value of 0.86 for CCFA.
Physical and optical properties of mineral dust aerosol measured by aircraft during the GERBILS campaign
Authors: Johnson B. T. , Osborne S. R.
Published: May 2011

This paper presents aircraft measurements of the physical and optical properties of mineral dust from the GERBILS campaign. The campaign involved ten flights of the UK Facility for Airborne Atmospheric Measurements (FAAM) BAe‐146 aircraft over the western region of the Sahara desert. Vertical profiles showed dust layers at varying altitudes extending as high as 6.5 km. Dust layers were typically associated with a deep well‐mixed boundary layer or a residual boundary layer above (the Saharan air layer). Aerosol optical depths (AODs), measured by integrating vertical profiles of extinction coefficient, ranged from 0.3 to 2.4 (at 0.55 μm). Aircraft AODs were generally within 20% of AERONET and Microtops sun‐photometer measurements. Single‐scattering albedos at 0.55 μm were measured in the range 0.92–0.99 with a campaign mean of 0.97. The in situ size distribution compared well with AERONET retrievals made at Banizoumbou (Niger) and Dakar (Senegal). The proportion of aerosol volume associated with particles of radii >1.5 μm was highly variable and also more difficult to measure. Models of dust as spheres, spheroids and more complex irregular‐shaped particles were used to calculate single‐scattering optical properties. The single‐scattering albedo showed a low sensitivity to particle shape. The asymmetry parameter and specific extinction coefficient showed greater sensitivity to particle shape. Copyright © 2011 British Crown copyright, the Met Office. Published by John Wiley & Sons Ltd.
Assignable causes of variation and statistical models: another approach to an old topic
Authors: Adler, Y. , Shper V. , Maksimova O.
Published: May 2011

This paper presents a fresh approach to the analysis of Shewhart control chart's performance. We consider two different types of assignable causes of variation. One—called type I—affects only the parameters of a model of the underlying distribution. The other—called type X—impacts the type of the original distribution. We analyze cases when the underlying normal distribution transforms into a uniform and log‐normal distribution after the intervention of an assignable cause of variation. It is shown that the Power Functions for control charts for individual measurements and control charts for means differ significantly from the well‐known traditional studies. We believe that this approach may open up new areas of research in the field of Statistical Process Control (SPC) and extend the spheres of SPC applications in practice. Copyright © 2011 John Wiley & Sons, Ltd.
The variable sampling interval X̄ chart with estimated parameters
Authors: Zhang Ying , Castagliola Philippe , Wu Zhang , Khoo Michael B. C.
Published: May 2011

The VSI chart has been investigated by many researchers under the assumption of known process parameters. However, in practice, these parameters are usually unknown and it is necessary to estimate them from the past data. In this paper, we evaluate and compare the performance of the VSI chart in terms of its average time to signal in the case where the process parameters are known and in the case where these parameters are estimated. We also provide new chart constants taking into account the number of phase I samples. Copyright © 2011 John Wiley & Sons, Ltd.
Electric and magnetic dipole shielding constants for the ground state of the relativistic hydrogen‐like atom: Application of the Sturmian expansion of the generalized Dirac‐Coulomb Green function
Authors: Stefańska Patrycja , Szmytkowski Radosław
Published: May 2011

The Sturmian expansion of the generalized Dirac‐Coulomb Green function (Szmytkowski, J Phys B, 1997, 30, 825; erratum 1997, 30, 2747) is exploited to derive closed‐form expressions for electric
$(\sigma_{E})$
and magnetic $(\sigma_{M})$
dipole shielding constants for the ground state of the relativistic hydrogen‐like atom with a point‐like and spinless nucleus of charge Ze. It is found that $\sigma_{E}=Z^{-1}$
(as it should be) and

where
$\gamma_{1}=\sqrt{1-(Z\alpha)^{2}}$
(α is the fine‐structure constant). This expression for $\sigma_{M}$
agrees with earlier findings of several other authors, obtained with the use of other analytical techniques, and is elementary compared to an alternative one presented recently by Cheng et al. (J Chem Phys 2009, 130, 144102), which involves an infinite series of ratios of the Euler's gamma functions. © 2011 Wiley Periodicals, Inc. Int J Quantum Chem, 2012
A robotic endoscope based on minimally invasive locomotion and wireless techniques for human colon
Authors: Gao Peng , Yan Guozheng , Wang Zhiwu , Wang Kundong , Jiang Pingping , Zhou Yilu
Published: May 2011

Background

Traditional endoscopy may cause tissue trauma and discomfort to patients because of the use of relatively long and semi‐rigid scopes.

Methods

A wireless robotic endoscope has been designed based on minimally invasive locomotion and wireless techniques for energy, monitoring, and telecontrol.

Results

The robotic endoscope can move forward or backward effectively in a smooth synthetic glass tube. The increase of the tube dip angle reduces the relative speed. The robot moves with lower efficiency because of the viscoelasticity of intestinal tissue in in vitro pig colon. The wireless power system can continuously and stably provide a minimum 378 mW energy, which exceeds the maximum system consumption. The video system realizes wireless image transmission at 30 frames per second. Doctors control the robot remotely using a communication frequency of 433 MHz.

Conclusions

The prototype robot shows the possibility of clinical application, but needs further improvement and testing. Copyright © 2011 John Wiley & Sons, Ltd.
Robotic central pancreatectomy with stented pancreaticogastrostomy: operative details
Authors: Addeo Pietro , Marzano Ettore , Nobili Cinzia , Bachellier Philippe , Jaeck Daniel , Pessaux Patrick
Published: May 2011

Background

Central pancreatectomy (CP) is increasingly being used to treat selected lesions of the central pancreatic segment. A step‐by‐step technique for robotic CP is described and a literature review provided for this minimally invasive approach.

Methods

A 55‐year‐old woman was referred to the authors' center for the treatment of a single 4 cm lesion located at the proximal part of the pancreatic body. The da Vinci Robotic surgical system® with a five trocar technique was used. The pancreatic neck was transected using an endoscopic stapler. The pancreatic body was progressively dissected from the splenic vessels right to left and sectioned with an appropriate oncologic margin. A pancreaticogastrostomy protected by a transanastomotic external stent was constructed to the distal pancreatic stump.

Results

Surgery lasted 450 min (8 min docking time) with minimal blood loss. Pathology showed a 28 mm well‐differentiated neuroendocrine pancreatic tumor with tumor‐free resection margins. The patient was discharged home on postoperative day 15 in good condition.

Conclusions

Robotic surgery can be safely used for complex pancreatic resection requiring pancreaticoenteric reconstruction. The experience reported so far is still limited but the results are encouraging; robotics shows the potential to bridge the gap between minimally invasive surgery and advanced pancreatic surgery. Copyright © 2011 John Wiley & Sons, Ltd.
Graphic and haptic simulation system for virtual laparoscopic rectum surgery
Authors: Pan Jun J. , Chang Jian , Yang Xiaosong , Zhang Jian J. , Qureshi Tahseen , Howell Robert , Hickish Tamas
Published: May 2011

Background

Medical simulators with vision and haptic feedback techniques offer a cost‐effective and efficient alternative to the traditional medical trainings. They have been used to train doctors in many specialties of medicine, allowing tasks to be practised in a safe and repetitive manner. This paper describes a virtual‐reality (VR) system which will help to influence surgeons' learning curves in the technically challenging field of laparoscopic surgery of the rectum.

Methods

Data from MRI of the rectum and real operation videos are used to construct the virtual models. A haptic force filter based on radial basis functions is designed to offer realistic and smooth force feedback. To handle collision detection efficiently, a hybrid model is presented to compute the deformation of intestines. Finally, a real‐time cutting technique based on mesh is employed to represent the incision operation.

Results

Despite numerous research efforts, fast and realistic solutions of soft tissues with large deformation, such as intestines, prove extremely challenging. This paper introduces our latest contribution to this endeavour. With this system, the user can haptically operate with the virtual rectum and simultaneously watch the soft tissue deformation.

Conclusions

Our system has been tested by colorectal surgeons who believe that the simulated tactile and visual feedbacks are realistic. It could replace the traditional training process and effectively transfer surgical skills to novices. Copyright © 2011 John Wiley & Sons, Ltd.
A survey of security visualization for computer network logs
Authors: Zhang Yanping , Xiao Yang , Chen Min , Zhang Jingyuan , Deng Hongmei
Published: May 2011

Network security is an important area in computer science. Although great efforts have already been made regarding security problems, networks are still threatened by all kinds of potential attacks, which may lead to huge damage and loss. Log files are main sources for security analysis. However, log files are not user friendly. It is laborious work to obtain useful information from log files. Compared with log files, visualization systems designed for security purposes provide more perceptive and effective sources for security analysis. Most security visualization systems are based on log files. In this paper, we provide a survey on visualization designs for computer network security. In this survey, we looked into different security visual analytics, and we organized them into five categories. Copyright © 2011 John Wiley & Sons, Ltd.
Privacy‐protected communication for location‐based services
Authors: Werner Martin
Published: May 2011

Location‐based services (LBSs) are emerging fast, and the problems with privacy are growing with them. Although a platform for LBSs can provide the user with high‐quality LBS browsing and powerful mechanisms to reduce the amount of location data transmitted, such a platform is dangerous because it has to manage the location data of the users and the actual service use. This aggregation of private data is a risk in itself. With this paper, we want to show that it is possible to implement most LBSs without such a platform and propose a mechanism enabling fine‐grained control of privacy for an LBS user. We make use of strong cryptographic techniques to enable a real trust relation between individuals and a weaker trust relation between an individual and a company. Copyright © 2011 John Wiley & Sons, Ltd.
Abdominal and Pelvic Injuries Caused by Road Traffic Accidents: Characteristics and Outcomes in a French Cohort of 2,009 Casualties
Authors: Cheynel Nicolas , Gentil Julie , Freitz Marc , Rat Patrick , Ortega Deballon Pablo , Bonithon Kopp C.
Published: May 2011

Background

The frequency, characteristics, and effect on outcome of abdominal and pelvic injuries (API) caused by road traffic accidents are not well known. We studied them in a well‐defined geographical area in France.

Methods

The medical data of all hospitalized victims of road traffic accidents that occurred over a 3‐year period were recorded. Injuries were coded according to the Abbreviated Injury Scale (AIS). The Injury Severity Score (ISS) was calculated. Continuous and qualitative variables were described by means and standard deviations or medians and percentages, respectively. Proportions and means were compared using the χ2 and Student tests, respectively.

Results

Of 6,977 victims of road traffic accidents, 2,009 were hospitalized (mean ISS = 7.9). API were present in 9.3% (n = 186) of all hospitalized victims and in 32.2% (n = 82) of the most severely injured (ISS ≥ 16, n = 255) hospitalized victims. The most frequently seriously injured abdominopelvic organs (AIS ≥ 3) were the spleen, the retroperitoneal organs, and the liver. The mean ISS and the mortality rate were significantly higher for victims with API than those without API (17.5 vs. 6.9, P < 0.001; 9.7% vs. 1.9%, P < 0.001). In multivariate analysis, the presence of severe API increased the mortality rate by a factor of 2.5.

Conclusions

In this study, API were present in one third of the most severely injured victims of road traffic accidents and were a significant factor of gravity and mortality. This study, conducted in France where there is no National Trauma Registry, underlined the need for establishing such registry.
Belowground responses of Picea asperata seedlings to warming and nitrogen fertilization in the eastern Tibetan Plateau
Authors: Liu Qing , Yin Huajun , Chen Jinsong , Zhao Chunzhang , Cheng Xinying , Wei Yunyan , Lin Bo
Published: May 2011

The impacts of global climatic change on belowground ecological processes of terrestrial ecosystems are still not clear. We therefore conducted an experiment in the subalpine coniferous forest ecosystem of the eastern edges of the Tibetan Plateau to study roots of Picea asperata seedlings and rhizosphere soil responses to soil warming and nitrogen availability from April 2007 to December 2008. The seedlings were subjected to two levels of temperature (ambient; infrared heater warming) and two nitrogen levels (0 or 25 g m−2year−1 N). We used a free air temperature increase from an overhead infrared heater to raise both air and soil temperature by 2.1 and 2.6°C, respectively. The results showed that warming alone significantly increased total biomass, coarse root biomass and fine root biomass of P. asperata seedlings. Both total biomass and fine root biomass were increased, but coarse root biomass was significantly decreased by nitrogen fertilization and warming combined with nitrogen fertilization. Warming induced a prominent increase in soil organic carbon (SOC) and NO3−‐N of rhizosphere soil, while nitrogen fertilization significantly decreased SOC and NH4+‐N of rhizosphere soil. The warming, fertilization and warming × N fertilization interaction decreased soil microbial C significantly, but substantially increased soil microbial N. These results suggest that nitrogen deposition combined with warmer temperatures under future climatic change possibly will have no effect on fine root production of P. asperata seedlings, but could enhance the nitrification process of their rhizosphere soils in subalpine coniferous forests.
Productivity–species richness relationship changes from unimodal to positive linear with increasing spatial scale in the Inner Mongolia steppe
Authors: Zhang Qing , Niu Jianming , Buyantuyev Alexander , Zhang Jing , Ding Yong , Dong Jianjun
Published: May 2011

Productivity–species diversity relationships have been a controversial research topic in ecology with scale believed to be among the main reasons for discovering different relationships. We collected data on species diversity (richness) and productivity (peak above‐ground biomass) of the Stipa breviflora association in the Inner Mongolia grassland to examine spatial scale dependency and possible underlying mechanisms responsible for the relationships found. One local and seven different landscape scales (the first level corresponds in extent to a 100 × 100 km area, which is increased consecutively by 100 km resulting in the 700 × 700 km area at the highest level) were considered. We found that: (1) unimodal relationships dominated the local scale, but this varied depending on the position along successional gradients; (2) a positive linear relationship was common at larger spatial scales; (3) biotic processes were the most likely primary factor underlying local scale unimodal relationships, but environmental heterogeneity (precipitation patterns) was the main determinant of relationships found at larger spatial scales; (4) our study contributed to other empirical evidence and predictions of theoretical models regarding scale dependency of productivity–species richness relationships; (5) while earlier research demonstrated positive linear species richness–productivity relationships across a number of ecological scales in the Inner Mongolia steppe, our study specifically tested a spectrum of geographical scales to confirm the scale‐dependency of this relationship. Lastly, our study emphasized the critical role played by precipitation patterns in controlling biodiversity and grassland ecosystem functioning, which maintains the relatively high level of biodiversity and stable ecosystem processes.
Midday depression of tree root respiration in relation to leaf transpiration
Authors: Bekku Yukiko Sakata , Sakata Tsuyoshi , Tanaka Tadashi , Nakano Takashi
Published: May 2011

The root respiration rate often shows an exponential or a linear relationship with temperature under laboratory conditions. However, under intact conditions in the field, the root respiration rates of some tree species decreased around midday despite an increment of the root temperature (Bekku et al. 2009). To clarify the cause of midday depression, we examined the relationships between the intact root respiration and parameters of leaf gas exchange through the simultaneous field measurement of the gas exchange in the leaf and root of Quercus crispula and Chamaecyparis obtusa, which are canopy trees. There were no significant relationships between the root respiration rates (Rr) and the parameters of leaf gas exchange in the field. However, in C. obtusa, the relationships between Rr and the transpiration rates (E) at 1 h before the measurement of Rr were fitted by logarithmic function with a determination coefficient of 0.60–0.89. In the light‐manipulation experiments using saplings, Rr had significant positive correlations with E at 20 min before the measurement of Rr, root temperature (Tr), and the photosynthesis (Pn) at 20 min before the measurement of Rr. We examined which factor, Pn or E, affects the root respiration rate through a manipulation experiment using a growth chamber regulating the ambient CO2 concentration and relative humidity independently under constant air temperature and photosynthetic photon flux density. As a result, the root respiration rates changed corresponding to E and not Pn. These results suggest that the root respiration rate of trees changes significantly in the daytime and is affected by the leaf transpiration rate as well as the temperature.
Use of the eight-Plate for angular correction of knee deformities due to idiopathic and pathologic physis: Initiating treatment according to etiology
Authors: Boero Silvio , Michelis Maria Beatrice , Riganti Simone
Published: May 2011

Purpose

Angular deformities of the knee resulting from idiopathic, congenital, or acquired causes are commonly encountered in pediatric orthopedics. Whereas physiological deformities should be treated expectantly, the remaining often progress enough to warrant operative treatment, despite attempted bracing. Historical methods of surgical treatment (e.g., epiphysiodesis and stapling) have yielded to the increasingly popular method of reversible guided growth using the eight-Plate.

Methods

We studied 58 patients with knee angular deformities managed with eight-Plate guided growth. All etiologies except physiological deformities and those with very slow growth rate were included. Each patient was under appropriate medical management during the entire duration of treatment and after plate removal.

Results

In the dysplasia/syndrome group, we noted complete correction in 22 patients (78.5%), partial correction in 5 (17.9%), and no correction in 1 patient (3.6%). All cases of idiopathic deformities resolved. Patients with osteochondral dysplasias and genetic syndromes underwent earlier intervention and slower correction than those with idiopathic genu varum or valgum. The time difference in reaching a neutral mechanical axis between the two groups (11 months in idiopathic versus 18 months in pathological physis) could be explained by a significant difference in growth speeds ( P = 0.003).

Conclusion

Results indicate that early intervention is advisable for patients with osteochondral dysplasias/syndromes as subsequent correction takes longer. If rebound growth causing recurrent deformity occurs, guided growth can be safely repeated. Additionally, complications reported with other techniques such as hardware failure, physeal violation by the implant, premature physeal closure, and overcorrection were not reported while using the eight-Plate.
Acute Multifocal Haematogenous Osteomyelitis in Children
Authors: Sreenivas T. , Nataraj A. R. , Menon Jagdish , Patro D. K.
Published: May 2011

Purpose

Haematogenous multifocal osteomyelitis in children represents a dangerous form of osteomyelitis in which sepsis can develop quickly if it is not treated early. A retrospective analysis of 26 children with acute multifocal haematogenous osteomyelitis over a period of 5 years was undertaken in order to assess the clinical presentation, infective organism, laboratory investigations and risk factors involved.

Methods

Children more than 1 year of age with two or more bones involvement presenting within one week from the onset of symptoms were included in this study. All of the children were evaluated by clinical examination, blood tests and local ultrasound.

Results

The average age at presentation was 4.9 years and girls were affected more than boys, with a female to male ratio of 1.4. Lower limbs were affected in 92% of cases, and, specifically, the tibia in 73.1% of the patients. Blood culture was positive in 38.5% of our cases. The predominant microorganism isolated from surgical samples was Staphylococcus aureus, among which methicillin-resistant S. aureus (MRSA) was found in 50% of the patients. Surgical drainage of the pus was done in 24 cases, followed by appropriate antibiotics, and two cases were treated by conservative means. All of the children were successfully treated except for four, who developed chronic osteomyelitis and sequelae.

Conclusion

We conclude that acute multifocal haematogenous osteomyelitis in children needs early diagnosis by a high index of clinical suspicion and adequate treatment with timely intervention. The predominance of MRSA in our study shows the changing trend in its association with multiple bone involvement.
Electric current of an electrified jet issuing from a long metallic tube
Authors: HIGUERA F. J.
Published: May 2011

This paper presents an analysis of the transport of electric current in a jet of an electrically conducting liquid discharging from a metallic tube into a gas or a vacuum, and subject to an electric field due to a high voltage applied between the tube and a far electrode. The flow, the surface charge and the electric field are computed in the current transfer region of the jet, where conduction current in the liquid becomes surface current due to the convection of electric charge accumulated at its surface. The electric current computed as a function of the flow rate of the liquid injected through the tube increases first as the square root of this flow rate, levels to a nearly constant value when the flow rate is increased and finally sets to a linear increase when the flow rate is further increased. The current increases linearly with the applied voltage at small and moderate values of this variable, and faster than linearly at high voltages. The characteristic length and structure of the current transfer region are determined. Order-of-magnitude estimates for jets which are only weakly stretched by the electric stresses are worked out that qualitatively account for some of the numerical results.
The application of boundary layer independence principle to three-dimensional turbulent mixing layers
Authors: WYGNANSKI ISRAEL , TEWES PHILIPP , KURZ HOLGER , TAUBERT LUTZ , CHEN CHUNMEI
Published: May 2011

Turbulent mixing layers emanating from slanted trailing edges or nozzles evolve in a manner that is explainable by applying the independence principle to boundary layer flows. Although measurements downstream of a planar chevron splitter plate validate the concept, the intent of this short article is to re-examine the broader ramifications of this observation. Turbulent boundary layer growth on a yawed flat plate is re-examined as is the attached flow direction near the trailing edge of a highly swept-back wing.
Strategic Opposition and Government Cohesion in Westminster Democracies
Authors: DEWAN TORUN , SPIRLING ARTHUR
Published: May 2011

Cohesive government-versus-opposition voting is a robust empirical regularity in Westminster democracies. Using new data from the modern Scottish Parliament, we show that this pattern cannot be explained by similarity of preferences within or between the government and opposition ranks. We look at differences in the way that parties operate in Westminster and Holyrood, and use roll call records to show that the observed behavior is unlikely to be determined by preferences on any underlying issue dimension. Using a simple variant of the agenda-setting model—in which members of parliament can commit to their voting strategies—we show that the procedural rules for reaching collective decisions in Westminster systems can explain this phenomenon: in the equilibrium, on some bills, members of the opposition vote against the government irrespective of the proposal. Such strategic opposition can reinforce government cohesiveness and have a moderating effect on policy outcomes. We introduce new data from the House of Lords, the Welsh Assembly, and the Northern Ireland Assembly to distinguish our claims from competing accounts of the data.
The Structure of Inequality and the Politics of Redistribution
Authors: LUPU NOAM , PONTUSSON JONAS
Published: May 2011

Against the current consensus among comparative political economists, we argue that inequality matters for redistributive politics in advanced capitalist societies, but it is the structure of inequality, not the level of inequality, that matters. Our theory posits that middle-income voters will be inclined to ally with low-income voters and support redistributive policies when the distance between the middle and the poor is small relative to the distance between the middle and the rich. We test this proposition with data from 15 to 18 advanced democracies and find that both redistribution and nonelderly social spending increase as the dispersion of earnings in the upper half of the distribution increases relative to the dispersion of earnings in the lower half of the distribution. In addition, we present survey evidence on preferences for redistribution among middle-income voters that is consistent with our theory and regression results indicating that left parties are more likely to participate in government when the structure of inequality is characterized by skew.
Economics, History, and Causation
Authors: Morck Randall , Yeung Bernard
Published: May 2011

Economics and history both strive to understand causation: economics by using instrumental variables econometrics, and history by weighing the plausibility of alternative narratives. Instrumental variables can lose value with repeated use because of an econometric tragedy of the commons: each successful use of an instrument creates an additional latent variable problem for all other uses of that instrument. Economists should therefore consider historians' approach to inferring causality from detailed context, the plausibility of alternative narratives, external consistency, and recognition that free will makes human decisions intrinsically exogenous.