bluuebunny/crossref_metadata_2025 huggingface dataset:
Frequency‐domain equalisation for block CDMA transmission
Authors: Adachi F. , Nakajima A. , Takeda K. , Liu L. , Tomeba H. , Yui T. , Fukuda K.
Published: June 2008

In next generation wireless network, significantly higher rate data services of close to 1 Gpbs are expected. The wireless channels for such a broadband data transmission become severe frequency‐selective. Frequency‐domain equalisation (FDE) technique may play an important role for broadband data transmission using multi‐carrier (MC)‐ and direct‐sequence code division multiple access (DS‐CDMA). The performance can be further improved by the use of multi‐input/multi‐output (MIMO) antenna diversity technique. The downlink performance is significantly improved with FDE. However, the uplink performance is limited by the multiple access interference (MAI). To remove the MAI while gaining the frequency diversity effect through the use of FDE, two‐dimensional (2D) block spread CDMA can be used. Recently, particular attention has been paid to MIMO space division multiplexing (SDM) to significantly increase the throughput without expanding the signal bandwidth. In this paper, we present a comprehensive performance comparison of MC‐ and DS‐CDMA using FDE. Copyright © 2008 John Wiley & Sons, Ltd.
Range improvement of UWB systems using adaptive multicarrier spread‐spectrum and MIMO techniques
Authors: Stephan Antoine , Baudais Jean‐Yves , Hélard Jean‐François
Published: June 2008

In this paper, we investigate the use of multiple‐input multiple‐output (MIMO) techniques with a linear precoded orthogonal frequency division multiplexing (LP‐OFDM) waveform, known as spread‐spectrum multicarrier multiple access (SS‐MC‐MA), for high data rate ultra‐wideband (UWB) systems. This scheme is an evolution of the well‐known multiband OFDM (MB‐OFDM) solution supported by the WiMedia Alliance. The aim of this paper is to improve the UWB system range while not significantly increasing the system complexity compared to the WiMedia solution. Firstly, an analytical study of the single‐input single‐output (SISO) LP‐OFDM waveform allows to find how to efficiently precode an OFDM signal in order to improve the system range. To go further and exploit the available spatial diversity, a MIMO component is added and a new geometric statistic MIMO channel model is considered. Secondly, a global MIMO LP‐OFDM system study is led to highlight the benefits of combining MIMO and LP techniques for UWB applications. The analytical and simulation results show that the joint use of MIMO and LP‐OFDM leads to a significant range improvement compared to the WiMedia solution. Copyright © 2008 John Wiley & Sons, Ltd.
Food group intake and risk of subtypes of esophageal and gastric cancer
Authors: Navarro Silvera Stephanie A. , Mayne Susan T. , Risch Harvey , Gammon Marilee D. , Vaughan Thomas L. , Chow Wong‐Ho , Dubrow Robert , Schoenberg Janet B. , Stanford Janet L. , West A. Brian , Rotterdam Heidrun , Blot William J. , Fraumeni Joseph F.
Published: June 2008

Incidence rates for adenocarcinomas of the esophagus and gastric cardia have been increasing rapidly, while rates for non‐cardia gastric adenocarcinoma and esophageal squamous cell carcinoma have declined. We examined food group intake as a risk factor for subtypes of esophageal and gastric cancers in a multicenter, population‐based case–control study in Connecticut, New Jersey and western Washington state. Associations between food groups and risk were estimated using adjusted odds ratios (OR), based on increasing intake of one serving per day. Total vegetable intake was associated with decreased risk of esophageal adenocarcinoma (OR = 0.85, 95% CI = 0.75, 0.96). Conversely, total meat intake was associated with increased risk of esophageal adenocarcinoma (OR = 1.43, 95% CI = 1.11, 1.83), gastric cardia adenocarcinoma (OR = 1.37, 95% CI = 1.08, 1.73) and noncardia gastric adenocarcinoma (OR = 1.39, 95% CI = 1.12, 1.71), with red meat most strongly associated with esophageal adenocarcinoma risk (OR = 2.49, 95% CI = 1.39, 4.46). Poultry was most strongly associated with gastric cardia adenocarcinoma (OR = 1.89, 95% CI = 1.15, 3.11) and noncardia gastric adenocarcinoma (OR = 1.90, 95% CI = 1.19, 3.03). High‐fat dairy was associated with increased risk of both esophageal and gastric cardia adenocarcinoma. Higher intake of meats, particularly red meats, and lower intake of vegetables were associated with an increased risk of esophageal adenocarcinoma, while higher intake of meats, particularly poultry, and high‐fat dairy was associated with increased risk of gastric cardia adenocarcinoma. © 2008 Wiley‐Liss, Inc.
UV irradiation increases ROS production via PKCδ signaling in primary murine fibroblasts
Authors: Bossi Orit , Gartsbein Marina , Leitges Michael , Kuroki Toshio , Grossman Shlomo , Tennenbaum Tamar
Published: June 2008

Ultraviolet (UV) irradiation is a major environmental factor responsible for a high incidence of premature skin aging, referred to as photoaging, as well as skin cancer and melanoma. UVA irradiation represents 90% of the solar UV light reaching the earth's surface, and yet the mechanisms by which it exerts its biological effects are not clear. UVA penetrates into the skin tissue, reaching the basal layers of the active dividing cells and, therefore, the contribution of UVA to skin damage may be significant. The majority of UVA energy is absorbed by unidentified photosensitizers in the cells which are postulated to generate reactive oxygen species (ROS). It has been believed that both chronological aging and photoaging share the same molecular features and, as such, it is very common to utilize UV irradiation for induction of skin aging. To determine the involvement of protein kinase isoforms in chronological aging and photoaging, we utilized in vitro aging model systems of primary murine fibroblasts and primary fibroblasts isolated from PKC null mice. We show for the first time distinct involvement of PKC isoforms PKCδ and PKCα in photoaging versus cellular senescence. While chronological aging is accompanied by overexpression and activation of PKCα, UV irradiation and ROS production are associated with photoaging accompanied by PKCδ downregulation and nuclear translocation. J. Cell. Biochem. 105: 194–207, 2008. © 2008 Wiley‐Liss, Inc.
Study of a newly isolated thermophilic bacterium capable of Kuhemond heavy crude oil and dibenzothiophene biodesulfurization following 4S pathway at 60 °C
Authors: Torkamani Sarah , Shayegan Jalal , Yaghmaei Soheila , Alemzadeh Iran
Published: June 2008

BACKGROUND: To meet stringent emission standards stipulated by regulatory agencies, the oil industry is required to bring down the sulfur content in fuels. As some compounds cannot be desulfurized by existing desulfurizing processes (such as hydrodesulfurization, HDS) biodesulfurization has become an interesting topic for researchers. Most of the isolated biodesulfurizing microorganisms are capable of desulfurization of refined products whose predominant sulfur species are dibenzothiophenes so biocatalyst development is still needed to desulfurize the spectrum of sulfur‐bearing compounds present in whole crude.

RESULTS: The first desulfurizing bacterium active at 60 °C has been isolated, which reduces DBT concentration from 2 mmol L−1 to 0.1 mmol L−1 after 95 h, following the 4S pathway. Its DBT desulfurization pattern was represented by the Michaelis‐Menten equation. Various parameters such as Vmax, Km, µm, Ks and maximum specific DBT desulfurization rate were calculated which are 0.092 mmol L−1 h−1, 3.554 mmol L−1, 0.157 h−1, 3.722 mmol L−1 and 0.192 mmol L−1 DBT g−1 DCW (dry cell weight) h−1, respectively. It can desulfurize 50% of the sulfur content of Kuhemond heavy crude oil (KHC oil) with an initial sulfur content of 7.6%wt in 6 days. Its maximum specific desulfurization rate for KHC oil is equivalent to 0.005 g sulfur g−1 DCW h−1. The bacterium was isolated during a heavy crude oil biodesulfurization project initiated by PEDEC, a subsidiary of National Iranian Oil Company.

CONCLUSION: The KHC oil sulfur removal efficiency of the bacterium is approximately five times that of BBRC‐9016 bacterium. It removes sulfur selectively without using sulfur‐containing compounds as its carbon source. By applying various media during its isolation, the probability of screening the correct microorganism is increased. Copyright © 2008 Society of Chemical Industry
The influence of femoral internal and external rotation on cartilage stresses within the patellofemoral joint
Authors: Besier Thor F. , Gold Garry E. , Delp Scott L. , Fredericson Michael , Beaupré Gary S.
Published: June 2008

Internal and external rotation of the femur plays an important role in defining the orientation of the patellofemoral joint, influencing contact areas, pressures, and cartilage stress distributions. The purpose of this study was to determine the influence of femoral internal and external rotation on stresses in the patellofemoral cartilage. We constructed finite element models of the patellofemoral joint using magnetic resonance (MR) images from 16 volunteers (8 male and 8 female). Subjects performed an upright weight‐bearing squat with the knee at 60° of flexion inside an open‐MR scanner and in a gait laboratory. Quadriceps muscle forces were estimated for each subject using an electromyographic‐driven model and input to a finite element analysis. Hydrostatic and octahedral shear stresses within the cartilage were modeled with the tibiofemoral joint in a “neutral” position and also with the femur rotated internally or externally by 5° increments to ±15°. Cartilage stresses were more sensitive to external rotation of the femur, compared with internal rotation, with large variation across subjects. Peak patellar shear stresses increased more than 10% with 15° of external rotation in 75% of the subjects. Shear stresses were higher in the patellar cartilage compared to the femoral cartilage and patellar cartilage stresses were more sensitive to femoral rotation compared with femoral cartilage stress. Large variation in the cartilage stress response between individuals reflects the complex nature of the extensor mechanism and has clinical relevance when considering treatment strategies designed to reduce cartilage stresses by altering femoral internal and external rotation. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
Three‐dimensional knee joint kinematics during golf swing and stationary cycling after total knee arthroplasty
Authors: Hamai Satoshi , Miura Hiromasa , Higaki Hidehiko , Shimoto Takeshi , Matsuda Shuichi , Okazaki Ken , Iwamoto Yukihide
Published: June 2008

The expectation of returning to sports activities after total knee arthroplasty (TKA) has become more important to patients than ever. To our knowledge, no studies have been published evaluating the three‐dimensional knee joint kinematics during sports activity after TKA. Continuous X‐ray images of the golf swing and stationary cycling were taken using a large flat panel detector for four and eight post‐arthroplasty knees, respectively. The implant flexion and axial rotation angles were determined using a radiographic‐based, image‐matching technique. Both the golf swing from the set‐up position to the top of the backswing, and the stationary cycling from the top position of the crank to the bottom position of the crank, produced progressive axial rotational motions (p = 0.73). However, the golf swing from the top of the backswing to the end of the follow‐through produced significantly larger magnitudes of rotational motions in comparison to stationary cycling (p < 0.01). Excessive internal–external rotations generated from the top of the backswing to the end of the follow‐through could contribute to accelerated polyethylene wear. However, gradual rotational movements were consistently demonstrated during the stationary cycling. Therefore, stationary cycling is recommended rather than playing golf for patients following a TKA who wish to remain physically active. © 2008 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res
Synthesis of Block Copolypeptides by Click Chemistry
Authors: Agut Willy , Agnaou Reda , Lecommandoux Sébastien , Taton Daniel
Published: June 2008

A novel synthetic methodology to diblock copolypeptides was developed by ring‐opening polymerization (ROP) ofN‐carboxyanhydrides (NCAs) fromα‐ω‐functionalized initiators combined with the Huisgen 1,3 dipolar cycloaddition (click chemistry). Poly(γ‐benzyl‐L‐glutamate) (PBLGlu) and poly(trifluoroacetyl‐L‐Lysine) (PTFALys) containing either an azide or an alkyne functional group inα‐position were first synthesized by ROP of the corresponding NCA at room temperature in DMF as a solvent, using appropriateω‐amino‐containingα‐alkyne andα‐azido difunctional initiators. The copper(I)‐catalyzed coupling reactions ofα‐azido‐PBLGlu with theα‐alkyne‐PTFALys, on the one hand, and of theα‐alkyne‐PBLGlu with theα‐azido‐PTFALys, on the other hand were suitably accomplished in DMF. This afforded the targeted PBLGlu‐b‐PTFALys diblock copolypeptides possessing a triazole group in between the two blocks, as evidenced by SEC, IR, and NMR analysis. Block copolypeptides could be successfully purified by selective extraction with chloroform.

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The Electrical Conductivity of Graphite Nanoplatelet Filled Conjugated Polyacrylonitrile
Authors: Green Maya , Marom Gad , Li Jing , Kim Jang‐Kyo
Published: June 2008

The electrical conductivity of composites of exfoliated graphite nanoplatelets (GNPs), including bromine‐doped GNP, and conjugated polyacrylonitrile has been investigated. The focal point is the dual nature of the graphite nanoparticles, which exhibit both intrinsic electrical conductivity and doping capability of semi‐conductive polymers such as conjugated polyacrylonitrile to form charge‐transfer complexes. The conductivity is particularly enhanced in conjugated polyacrylonitrile composites (e.g., with 6 wt.‐% graphite nanoplatelets) where the value rises from 1 × 10−10 to 2 × 10−3 S · cm−1, which reflects jointly the conductivity of the doped semi‐conductive polymer together with the percolation‐based conductivity of the particles.

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Two‐dimensional chemotaxis models with fractional diffusion
Authors: Biler Piotr , Wu Gang
Published: June 2008

In this paper we study the Cauchy problem for the fractional diffusion equationut+ (−Δ)α/2u=∇·(u∇(Δ−1u)), generalizing the Keller–Segel model of chemotaxis, for the initial datau0in critical Besov spacesḂ(ℝ2) withr∈[1, ∞], where 1<α<2. Making use of some estimates of the linear dissipative equation in the frame of mixed time–space spaces, the Chemin ‘mono‐norm method,’ Fourier localization technique and the Littlewood–Paley theory, we obtain a local well‐posedness result. We also consider analogous ‘doubly parabolic’ models. Copyright © 2008 John Wiley & Sons, Ltd.
The generalized totally geodesic Radon transform and its application to texture analysis
Authors: Bernstein Swanhild , Hielscher Ralf , Schaeben Helmut
Published: June 2008

The generalized totally geodesic Radon transform associates the mean values over spherical tori to a functionfdefined on 𝕊3⊂ℍ, where the elements of 𝕊3are considered as quaternions representing rotations. It is introduced into the analysis of crystallographic preferred orientation and identified with the probability density function corresponding to the angle distribution functionW. Eventually, this communication suggests a new approach to recover an approximation offfrom data samplingW. At the same time it provides additional clarification of a recently suggested method applying reproducing kernels and radial basis functions by instructive insight into its involved geometry. The focus is on the correspondence of geometrical and group features rather than on the mapping of functions and their spaces. Copyright © 2008 John Wiley & Sons, Ltd.
Management of iatrogenic foreign bodies of the bladder and urethra following pelvic floor surgery
Authors: Frenkl Tara L. , Rackley Raymond R. , Vasavada Sandip P. , Goldman Howard B.
Published: June 2008

Objective

Literature regarding the management of iatrogenic foreign body in the bladder and urethra following female pelvic reconstructive surgery, especially mesh erosion, are sparse. We present our recent experience with the removal of iatrogenic foreign bodies from the bladder and urethra and propose a treatment algorithm.

Methods

A retrospective review yielded 22 patients with iatrogenic foreign body in the bladder or urethra between 1/1998 and 12/2005. Presenting complaints, cystoscopic findings, operative techniques, and outcomes were reviewed.

Results

Source surgery of the iatrogenic foreign bodies included bladder suspension in 9 patients, synthetic sling in 11 patients, abdominal sacrocolpopexy and porcine dermis sling in 1 patient each. The majority of patients presented with multiple voiding dysfunctions including overactive bladder symptoms (11), incontinence (5), chronic pelvic or urethral pain (7), urinary tract infections (7), obstructive voiding symptoms (5), and gross hematuria (3). Eleven cases were managed endoscopically, 4 using the holmium laser. One patient required subsequent cystorrhaphy. Four patients were managed with urethroplasty, 4 with cystorrhaphy, and the remainder utilizing a combination of techniques. No patients required complex reconstruction with interposition flaps.

Conclusions

The diagnosis of iatrogenic foreign bodies in the lower urinary tract requires a high index of suspicion and a low threshold for performing cystoscopy. From this series, we have found that sutures can most often be managed successfully with endoscopic techniques, whereas mesh is best managed with cystorrhaphy and/or urethroplasty. To our knowledge, our series represents the largest number of reported iatrogenic foreign body removals at a single institution. Neurourol. Urodynam. 27:491–495, 2008. © 2008 Wiley‐Liss, Inc.
The under‐controlled do it first: Childhood personality and sexual debut
Authors: Atkins Robert , Hart Daniel
Published: June 2008

The relationship of childhood personality type to the timing of first sexual intercourse was investigated through survival analysis. Participants from the Child Sample of the National Longitudinal Survey of Youth were categorized into one of the three personality types at 5 or 6 years of age: under‐controlled, resilient, and over‐controlled. Those categorized as under‐controlled at 5 or 6 years of age were more likely than those resilient or over‐controlled to have sexual intercourse before the age of 16. The extent to which three early adolescent factors—team/club membership, church attendance, and peer influence—mediate the association of childhood personality type to the timing of first sexual intercourse was also explored. The association of childhood personality to timing of first sexual intercourse was partially mediated by peer influence at 11 or 12 years of age. The findings are interpreted in light of their implications for researchers and practitioners interested in improving the health and well‐being of children and adolescents. © 2008 Wiley Periodicals, Inc. Res Nurs Health 31:626–639, 2008
A survey of Hong Kong nurses' perceptions of barriers to and facilitators of research utilization
Authors: Chau Janita P.C. , Lopez Violeta , Thompson David R.
Published: June 2008

A survey of 1,487 nurses was conducted to examine barriers to and facilitators of research utilization. Characteristics of the organization were the greatest barriers to research utilization; the highest ranked of these were inadequate facilities, lack of authority to change practice, lack of time, and lack of cooperation from physicians. The three highest ranked organizational facilitators were managerial support, colleague support, and education to increase nursing knowledge. Age and years of working experience were not significantly correlated with any of the subscales. To integrate the use of research evidence into the culture of various clinical settings, and with the aim of extending evidence‐based practice into the private and primary health care sectors in Hong Kong, local organizational barriers and facilitators need to be addressed. © 2008 Wiley Periodicals, Inc. Res Nurs Health 31:640–649, 2008
Prevalence of urinary incontinence among community‐dwelling adults receiving home care
Authors: Moulin M.F.M.T. Du , Hamers J.P.H. , Ambergen A.W. , Janssen M.A.P. , Halfens R.J.G.
Published: June 2008

We conducted a cross‐sectional survey in 2005 to determine the prevalence of and factors associated with urinary incontinence (UI) in adults receiving home care. Of the 2,866 patients surveyed, 46% suffered from UI; 6.5% had stress, 16.6% had urge, 9% had mixed, and 17.6% had functional incontinence. No diagnosis regarding type of UI had been established in 50.2%. Factors associated with UI were advanced age, higher body mass index, and impaired mobility. UI is prevalent in older persons receiving home care, but the lack of diagnosis of type of UI in half of the participants surveyed impedes management of UI. © 2008 Wiley Periodicals, Inc. Res Nurs Health 31:604–612, 2008
The role of the initial bone marrow aspirate in the diagnosis of hemophagocytic lymphohistiocytosis
Authors: Gupta Abha , Tyrrell Pascal , Valani Rahim , Benseler Susanne , Weitzman Sheila , Abdelhaleem Mohamed
Published: June 2008

Background

The identification of hemophagocytosis (HPC) in tissue or bone marrow (BM) represents only one of 5/8 criteria needed for the diagnosis of hemophagocytic lymphohistiocytosis (HLH). Yet, confirmation of HPC in bone marrow aspirates (BMA) is often relied upon to make therapeutic decisions. There is no standardized reporting criteria for the definition of “positive” BMA, and likely differs between institutions. The purpose of this study was to quantify the number of HPC in the initial BMA in patients diagnosed with HLH at our institution.

Procedure

Patient charts were retrospectively reviewed. Numbers of HPC were counted per 500 nucleated cells in initial BMA.

Results

Fifty‐eight percent of patients had at least one HPC per 500 nucleated cells. Median number of HPC per 500 cells was 1 (0–12). Median time from initial BMA to HLH diagnosis was 0 days (−3 to 11), suggesting that HLH diagnosis was made regardless of the results of this initial BMA.

Conclusion

The number of HPC at initial BMA is often low and variable, confirming that a BMA lacking HPC does not rule out the diagnosis of HLH, and a negative initial BMA should not delay therapy. We recommend that the BMA report should document negative as well as any positive findings of HPC. Pediatr Blood Cancer 2008;51:402–404. © 2008 Wiley‐Liss, Inc.
Estimation of the nucleation and crystal growth contributions to the overall crystallization energy barrier
Authors: Lorenzo A. T. , Müller A. J.
Published: June 2008

Classical kinetic theories of polymer crystallization were applied to isothermal crystallization kinetics data obtained by polarized optical microscopy (PLOM) and differential scanning calorimetry (DSC). The fitted parameters that were proportional to the energy barriers obtained allow us to quantitatively estimate the nucleation and crystal growth contributions to the overall energy barrier associated to the crystallization process. It was shown that the spherulitic growth rate energy barrier found by fitting PLOM data is almost identical to that obtained by fitting the isothermal DSC crystallization data of previously self‐nucleated samples. Therefore, we demonstrated that by self‐nucleating the material at the ideal self‐nucleation (SN) temperature, the primary nucleation step can be entirely completed and the data obtained after subsequent isothermal crystallization by DSC contains only contributions from crystal growth or secondary nucleation. In this way, by employing SN followed by isothermal crystallization, we propose a simple method to obtain separate contributions of energy barriers for primary nucleation and for crystal growth, even in the case of polymers where PLOM data are very difficult to obtain (because they exhibit very small spherulites). Comparing the results obtained with poly(p‐dioxanone), poly(ε‐caprolactone), and a high 1,4 model hydrogenated polybutadiene, we have interpreted the differences in primary nucleation energy barriers as arising from differences in nuclei density. © 2008 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 46: 1478–1487, 2008
Identification and characterization of a novel O‐superfamily conotoxin from Conus litteratus
Authors: Wang Lei , Pi Canhui , Liu Junliang , Chen Shangwu , Peng Can , Sun Dandan , Zhou Maojun , Xiang Hui , Ren Zhenghua , Xu Anlong
Published: June 2008

A novel conotoxin named lt6c, an O‐superfamily conotoxin, was identified from the cDNA library of venom duct of Conus litteratus. The full‐length cDNA contains an open reading frame encoding a predicted 22‐residue signal peptide, a 22‐residue proregion and a mature peptide of 28 amino acids. The signal peptide sequence of lt6c is highly conserved in O‐superfamily conotoxins and the mature peptide consists of six cysteines arranged in the pattern of CCCCCC that is defined the O‐superfamily of conotoxins. The mature peptide fused with thioredoxin, 6‐His tag, and a Factor Xa cleavage site was successfully expressed in Escherichia coli. About 12 mg lt6c was purified from 1L culture. Under whole‐cell patch‐clamp mode, lt6c inhibited sodium currents on adult rat dorsal root ganglion neurons. Therefore, lt6c is a novel O‐superfamily conotoxin that is able to block sodium channels. Copyright © 2008 European Peptide Society and John Wiley & Sons, Ltd.
The climatology of small‐scale orographic precipitation over the Olympic Mountains: Patterns and processes
Authors: Minder Justin R. , Durran Dale R. , Roe Gerard H. , Anders Alison M.
Published: June 2008

The climatology of small‐scale patterns of mountain precipitation is poorly constrained, yet important for applications ranging from natural hazard assessment to understanding the geologic evolution of mountain ranges. Synthesizing four rainy seasons of high‐resolution precipitation observations and mesoscale model output (from the Penn State/NCAR MM5), reveals a persistent small‐scale pattern of precipitation over the ∼10 km wide, ∼800 m high ridges and valleys of the western Olympic Mountains, Washington State, USA. This pattern is characterized by a 50–70% excess accumulation over the ridge crests relative to the adjacent valleys in the annual mean. While the model shows excellent skill in simulating these patterns at seasonal time‐scales, major errors exist for individual storms.

Investigation of a range of storm events has revealed the following mechanism for the climatological pattern. Regions of enhanced condensation of cloud water are produced by ascent in stable flow over the windward slopes of major ridges. Synoptically generated precipitation grows by collection within these clouds, leading to enhanced precipitation which is advected by the prevailing winds.

Instances of atypical patterns of precipitation suggest that under certain conditions (during periods with a low freezing level, or convective cells) fundamental changes in small‐scale patterns may occur. However, case‐studies and composite analysis suggest that departures from the pattern of ridge‐top enhancement are rare; the basic patterns and processes appear robust to changes in temperature, winds, and background rainfall rates. Copyright © 2008 Royal Meteorological Society
Secure, pseudonymous, and auditable communication in vehicularad hocnetworks
Authors: Kamat Pandurang , Baliga Arati , Trappe Wade
Published: June 2008

Vehicularad hocnetworks (VANETs) represent a promising new communication technology that can facilitate many new forms of automotive applications. Many of the applications that will run on these networks will require a high degree of security and privacy. In this paper, we present a robust and efficient security framework for vehicular networks suited for both inter‐vehicular and vehicle‐to‐infrastructure communication. Our system uses identity‐based cryptography (IBC) to provide authentication, confidentiality, non‐repudiation, and message integrity. It exploits the implicit authentication provided by IBC to significantly reduce the security/privacy‐related communication overhead. Additionally, it provides scalable, user‐customizable security and privacy using short‐lived, authenticated, and unforgeable, pseudonyms. This feature can be used by VANET applications that require quantifiable trust and privacy to provide differentiated service based on various levels of trust and privacy thresholds. Copyright © 2008 John Wiley & Sons, Ltd.
Preparation and Application of Fluorinated Cationic Surfactants
Authors: Mohamed M. Z.
Published: June 2008

Four fluorinated cationic surfactants were prepared by condensing 2,2,3,3, tetrafluoro‐1‐propyl chloroacetate with stoichiometric amounts of pyridine, 2‐hydroxypyridine, 8‐hydroxyquinoline and 8‐hydroxyquinaldine to produce four quaternary ammonium salts. The surface and biocidal properties of these surfactants were investigated. Surface properties of their solutions including surface tension, critical micelle concentration (CMC), effectiveness (Πcmc), maximum surface excess (Γmax) and minimum surface area (Amin) were investigated with respect to different concentrations at 25 °C. Standard free energies of micellization and adsorption of the prepared surfactants in the aqueous solution were studied. The biocidal activity was determined via the inhibition zone diameter of prepared compounds which tested against six strains as a representative group of microorganisms.
Fluorescence Techniques Using Dehydroergosterol to Study Cholesterol Trafficking
Authors: McIntosh Avery L. , Atshaves Barbara P. , Huang Huan , Gallegos Adalberto M. , Kier Ann B. , Schroeder Friedhelm
Published: June 2008

Cholesterol itself has very few structural/chemical features suitable for real‐time imaging in living cells. Thus, the advent of dehydroergosterol [ergosta‐5,7,9(11),22‐tetraen‐3β‐ol, DHE] the fluorescent sterol most structurally and functionally similar to cholesterol to date, has proven to be a major asset for real‐time probing/elucidating the sterol environment and intracellular sterol trafficking in living organisms. DHE is a naturally occurring, fluorescent sterol analog that faithfully mimics many of the properties of cholesterol. Because these properties are very sensitive to sterol structure and degradation, such studies require the use of extremely pure (>98%) quantities of fluorescent sterol. DHE is readily bound by cholesterol‐binding proteins, is incorporated into lipoproteins (from the diet of animals or by exchange in vitro), and for real‐time imaging studies is easily incorporated into cultured cells where it co‐distributes with endogenous sterol. Incorporation from an ethanolic stock solution to cell culture media is effective, but this process forms an aqueous dispersion of DHE crystals which can result in endocytic cellular uptake and distribution into lysosomes which is problematic in imaging DHE at the plasma membrane of living cells. In contrast, monomeric DHE can be incorporated from unilamellar vesicles by exchange/fusion with the plasma membrane or from DHE‐methyl‐β‐cyclodextrin (DHE‐MβCD) complexes by exchange with the plasma membrane. Both of the latter techniques can deliver large quantities of monomeric DHE with significant distribution into the plasma membrane. The properties and behavior of DHE in protein‐binding, lipoproteins, model membranes, biological membranes, lipid rafts/caveolae, and real‐time imaging in living cells indicate that this naturally occurring fluorescent sterol is a useful mimic for probing the properties of cholesterol in these systems.
Synthesis of Carbonated Vernonia Oil
Authors: Mann Noel , Mendon Sharathkumar K. , Rawlins James W. , Thames Shelby F.
Published: June 2008

The research objective was to determine whether naturally occurring epoxy functional vernonia oil would result in lower viscosity compounds after converting the virgin oil into the cyclic carbonate using supercritical carbon dioxide as the reactant. The cyclic carbonate was produced using relatively mild conditions as described in the paper. Carbonated vernonia oil retains the characteristic low viscosity of vernonia oil, and offers potential as a valuable, biobased intermediate for synthesizing low viscosity resins.
Evaluation of time memory in acutely depressed patients, manic patients, and healthy controls using a time reproduction task
Authors: Mahlberg Richard , Kienast Thorsten , Bschor Tom , Adli Mazda
Published: June 2008

Patients with affective disorders have often been reported to experience subjective changes in how they perceive the flow of time. Time reproduction tasks provide information about the memory component of time perception and are thought to remain unaffected by pulse rate disturbances in the pacemaker of the internal clock.

In our study, 30 patients with acute depression, 30 patients with acute mania, and 30 healthy subjects of all age groups were presented with a time reproduction task. Participants were asked to observe a stimulus presented on a computer screen for a certain length of time and, subsequently, to reproduce the stimulus for a similar length of time by pressing the space bar on the computer keyboard. Stimuli were presented to each subject for 1, 6, and 37 s.

On average, the time intervals reproduced by manic patients were shorter than those reproduced by depressed patients. Manic patients reproduced the short time interval (6 s) correctly, but under-reproduced the long time interval (37 s, P < 0.001). Depressed patients correctly reproduced the long time interval, but over-reproduced the short time interval (P < 0.001).

Remembering time intervals as having been longer than they actually were may lead to a slowed experience of time, as has been described in depressed patients; precisely the converse seems to apply to manic patients.
Kunneth theorems and unstable operations in 2-adic KO-cohomology
Authors: Bousfield A.K.
Published: June 2008

We develop Kunneth theorems and obtain detailed results on unstable operations in 2-adic KO-cohomology and, more generally, in united 2-adic K-cohomology. These results are needed for work on the K-localizations of spaces at the prime 2 and should be of independent interest. Our proofs of relations for unstable operations rely on Atiyah's Real K-theory and on a convenient mod 2 simplification of 2-adic KO-cohomology.
Myochroidea, a new genus of corticolous, crustose lichens to accommodate the Lecidea leprosula group
Authors: PRINTZEN Christian , SPRIBILLE Toby , TØNSBERG Tor
Published: June 2008

The new lichen genus Myochroidea is described to accommodate four species of the Lecidea leprosula group. Myochroidea is characterized by a crustose, areolate, minutely crenate to almost coralloid or indistinct, grey-brown to olive-brown thallus, reddish brown apothecia with an often persistent margin, moderately branched and anastomosing paraphyses with often swollen, pigmented apical cells, asci of the Micarea-type, and colourless, one-celled, fusiform to broadly ellipsoid ascospores. The new combinations Myochroidea leprosula (Arnold) Printzen, T. Sprib. & Tønsberg comb. nov., M. porphyrospoda (Anzi) Printzen, T. Sprib. & Tønsberg comb. nov., M. rufofusca (Anzi) Printzen, T. Sprib. & Tønsberg comb. nov. and the new species M. minutula Printzen, T. Sprib. & Tønsberg are published. Lecidea porphyroplaca Hinteregger & Poelt is a synonym of M. rufofusca. Descriptions of the four species and an identification key are provided. Myochroidea leprosula and M. rufofusca are reported as new to North America.
Paul and the Nomos in Light of Ritual Theory
Authors: GRUENWALD ITHAMAR
Published: June 2008

This article wishes to handle the subject of the Nomos in Paul from a new perspective, namely from Religious Studies, within a framework where rituals and Ritual Studies receive priority. Nomos is generally translated as ‘the Law’ (with a capital ‘L’), meaning the Torah of Moses, the Pentateuch; by implication, it also covers the rabbinic modes of Torah explication. Commonly, the term and the negation of its religious relevance mark the manner in which Christianity views itself as superseding Judaism. However, the article argues that this understanding of the term and its significance in the writings of Paul is wrongly oriented. Paul himself discusses the issue of religious rules and regulations as part of the life of the communities, which he addresses in his Letters. If Paul is taken at his own words, rituals are important components in Christianity. Thus, the ‘Protestant’ oriented criticism of the cult is tantamount to making Paul address issues that Paul has no intention to take at their face value. This article, therefore, intends to reach new conclusions with regard to the common understanding of Paul's handling of the subject of the Law.
Measuring the Temple of God: Revelation 11.1–2 and the Destruction of Jerusalem
Authors: DULK MATTHIJS DEN
Published: June 2008

Rev 11.1–2 refers to the destruction of the temple in 70 ce. The measuring of the temple area does not signify that it will be protected, as is commonly thought, but symbolises that it falls under God's judgment. The underlying idea is that the destruction of the temple at the hands of the Gentiles has been possible only because it was preceded by God's judgment, a notion also found in contemporary apocalyptic literature. John argues that God has given the Gentiles the authority to ‘trample the holy city’, including the temple, for a limited period of time.
Identification: The missing link between joint attention and
imitation?
Authors: HOBSON JESSICA A. , HOBSON R. PETER
Published: June 2008

In this paper we outline our hypothesis that human intersubjective
engagement entails identifying with other people. We tested a prediction
derived from this hypothesis that concerned the relation between a
component of joint attention and a specific form of imitation. The
empirical investigation involved “blind” ratings of videotapes
from a recent study in which we tested matched children with and without
autism for their propensity to imitate the self-/other-orientated
aspects of another person's actions. The results were in keeping with
three a priori predictions, as follows: (a) children with autism
contrasted with control participants in spending more time looking at the
objects acted upon and less time looking at the tester; (b) participants
with autism showed fewer “sharing” looks toward the tester,
and although they also showed fewer “checking” and
“orientating” looks, they were specifically less likely to
show any sharing looks; and, critically, (c) within each group,
individual differences in sharing looks (only) were associated with
imitation of self–other orientation. We suggest that the propensity
to adopt the bodily anchored psychological stance of another person is
essential to certain forms of joint attention and imitation, and that a
weak tendency to identify with others is pivotal for the developmental
psychopathology of autism.This research was
supported by the Economic and Social Research Council (award reference
R000239355), the Baily Thomas Charitable Foundation, and the Tavistock
Clinic, London (with NHS R&D funding). The manuscript was completed
while the authors were at the Center for Advanced Study in the Behavioral
Sciences, Stanford. We are grateful to the staff, students, and parents at
Edith Borthwick School, Helen Allison School, Springhallow School, and
Swiss Cottage School for their generous involvement in this project; Dave
Williams, Valentina Levi, and Susana Caló for their assistance with
ratings of joint attention; and Tony Lee and Rosa García
Pérez for their many contributions to the research.
Rainfall and sampling uncertainties: A rain gauge perspective
Authors: Villarini Gabriele , Mandapaka Pradeep V. , Krajewski Witold F. , Moore Robert J.
Published: June 2008

Rain gauge networks provide rainfall measurements with a high degree of accuracy at specific locations but, in most cases, the instruments are too sparsely distributed to accurately capture the high spatial and temporal variability of precipitation systems. Radar and satellite remote sensing of rainfall has become a viable approach to address this problem effectively. However, among other sources of uncertainties, the remote‐sensing based rainfall products are unavoidably affected by sampling errors that need to be evaluated and characterized. Using a large data set (more than six years) of rainfall measurements from a dense network of 50 rain gauges deployed over an area of about 135 km2 in the Brue catchment (south‐western England), this study sheds some light on the temporal and spatial sampling uncertainties: the former are defined as the errors resulting from temporal gaps in rainfall observations, while the latter as the uncertainties due to the approximation of an areal estimate using point measurements. It is shown that the temporal sampling uncertainties increase with the sampling interval according to a scaling law and decrease with increasing averaging area with no strong dependence on local orography. On the other hand, the spatial sampling uncertainties tend to decrease for increasing accumulation time, with no strong dependence on location of the gauge within the pixel or on the gauge elevation. For the evaluation of high resolution satellite rainfall products, a simple rule is proposed for the number of rain gauges required to estimate areal rainfall with a prescribed accuracy. Additionally, a description is given of the characteristics of the rainfall process in the area in terms of spatial correlation.
Numerical study of airflow in the unsaturated zone induced by sea tides
Authors: Guo Hai‐Peng , Jiao Jiu J.
Published: June 2008

The air pressures in coastal unsaturated zones fluctuate in response to tidal fluctuations. Two‐phase air‐water flow induced by sea tides in a coastal two‐layered subsurface system is investigated through numerical simulations. The system consists of upper and lower layers with permeabilities of kU and kL, respectively. A water table exists in the lower layer. The study demonstrates that airflow in the unsaturated zone is controlled by permeabilities of both layers and the fluctuation of water level. The tide‐induced water level fluctuation may result in significant air pressure fluctuation in the unsaturated zone in an air‐confined system; that is, the permeability of the upper layer is about 2 orders of magnitude lower than that of the lower layer. In such an air‐confined system, horizontal airflow is dominant in the lower layer and vertical airflow is dominant in the upper layer. The simulation results show that the hydraulic head, rather than the sea tide, is the direct driving force of the air pressure fluctuation above the water table. The study on the relation between the air pressure amplitude and the landward distance demonstrates that the air pressure amplitudes increase to a maximum and then decrease with distance. The amplitude of air pressure fluctuation decreases progressively with kU in the lower layer. In the upper layer, however, the amplitude tends to increase with kU when kU is very low and decrease with kU when kU is relatively high. Overall, the air flux fluctuations across the atmosphere‐soil interface attenuate landward gradually, and this attenuation becomes faster as the permeability of the upper layer increases.
On the dispersion relation for the kinetic Alfvén wave in an inhomogeneous plasma
Authors: Lysak Robert L.
Published: June 2008

The kinetic Alfvén wave has been recognized as an important wave mode in magnetospheric plasmas and laboratory plasmas, and has potential application in many areas of cosmic plasma physics. The kinetic dispersion relation of this mode has been described including finite frequency and finite ion gyroradius corrections. Laboratory plasmas as well as plasmas in space often contain strong gradients perpendicular to the background magnetic field. In this case, the dispersion relation must be generalized to include changes in the plasma parameters on each side of the gradient. In the presence of such gradients, localized modes can be found in the plasma. Depending on the relative values of the Alfvén speed and the plasma beta across these gradients, these modes can be trapped within the cavity or enhancement or propagate across the gradient.
The load dependence of rate constants
Authors: Walcott Sam
Published: June 2008

As experimental techniques in biophysics have progressed at the single molecule level, there has been considerable interest in understanding how external mechanical influences (such as load) affect chemical reactions. The majority of biophysical studies investigating load-dependent kinetics use an equation where the rate constant exponentially depends on force, which is sometimes called Bell’s equation. This equation requires the determination of two parameters that describe the potential energy-strain function: k0, which is the reaction rate in the absence of load, and xc, which is the difference in strain between the reactant and transition states. However, there have been theoretical studies based on Kramers’ theory suggesting that the rate constant should have load-dependent pre-exponential terms and nonlinear load-dependent terms in the exponential. Kramers’ theory requires an exact knowledge of the potential energy-strain function, which is in general not known for an experimental system. Here, we derive a general approximation of Kramers’ theory where the potential energy–strain function is described by five parameters, which can, for small loads, be reduced to four-, three-, and finally to two parameters (Bell's equation). We then use an idealized physical system to validate our approximations to Kramers’ theory and show how they can predict parameters of interest (such as k0 and xc) better than Bell’s equation. Finally, we show previously published experimental data that are not well fitted by Bell’s equation but are adequately fitted by these more exact equations.
Filamentation of dispersive Alfvén waves in density channels: Hall magnetohydrodynamics description
Authors: Borgogno D. , Laveder D. , Passot T. , Sulem C. , Sulem P. L.
Published: June 2008

Filamentation of dispersive Alfvén waves initiated by low or high density channels (depending on the plasma beta) is simulated numerically in the framework of ideal Hall magnetohydrodynamics, and asymptotically modeled with a two-dimensional nonlinear Schrödinger equation including a linear attracting potential. Compared with the dynamics in a homogeneous plasma, the phenomenon is accelerated and occurs for a broader range of parameters. In the case of an isolated channel with a width comparable to the pump wavelength, the transverse wave collapse can be replaced by a moderate amplification. In many cases, a relatively complex dynamics takes place, characterized by an oscillation between magnetic filaments and magnetic ribbons, leading to the formation of small scales at which dissipative effects could become relevant. Alfvén vortices, governed by the equations of the reduced magnetohydrodynamics, are also identified in the simulations, in spite of their small amplitude relative to the wave. The formation of structures under the effect of periodic or random distributions of low and high density channels is also discussed.
Two-carrier transport and ferromagnetism in FeSe thin films
Authors: Wu X. J. , Zhang Z. Z. , Zhang J. Y. , Li B. H. , Ju Z. G. , Lu Y. M. , Li B. S. , Shen D. Z.
Published: June 2008

α - and β-FeSe thin films were grown by metal organic chemical vapor deposition. Compared to the other parameters, the growth temperature shows decisive influence on the phase transition of the FeSe samples. In temperature-dependent electrical measurements, n-type to p-type reversion was observed for both the α- or and β-FeSe samples. Furthermore, the p-type character of the films becomes more and more obvious with increasing the Se∕Fe atomic ratio in the samples. Ferromagnetism was observed in the α-FeSe films although which is not supported by calculation on density of states. The ferromagnetic character shows significant dependence on Se∕Fe atomic ratio in the films and was attributed to the Fe vacancies or Fe clusters in the α-FeSe thin films. The magnetic domain and hysteresis loop of the β-FeSe thin films are also studied.