bluuebunny/crossref_metadata_2025_split huggingface dataset:
On the study of liquid crystalline materials using positron annihilation spectroscopy
Authors: Singh K. Chandramani 
Published: October 2009

AbstractPositron annihilation spectroscopy (PAS) has emerged as a powerful technique for investigating structural changes, phase transformations and micro environmental transformations in a variety of systems. Positron lifetime technique has been employed to investigate various liquid crystalline materials, both thermotropic and lyotropic. Investigations in thermotropic liquid crystalline materials, besides detection of various phase transformations, have revealed solid crystalline polymorphism in some systems. In some thermotropic liquid crystalline materials, the ortho‐positronium (o‐Ps) pick‐off lifetime shows changes which strongly support (i) retention of some memory of more ordered solid phases on passing to the liquid crystalline phase, (ii) strong tendency for the molecules in the mesophases to undergo anti‐parallel bimolecular association, and (iii) the formation of cybotactic groups in a nematic medium. The present paper illustrates some of these features. A work on supercooled states has demonstrated the possibility of using PAS for studying various intra‐ and inter‐molecular motions associated with the molecules of liquid crystalline materials. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The SOP model of change as a new way of looking at causality
Authors: Glassop Linda Irene 
Published: October 2009

AbstractThis research note sets out a multi‐faceted view of causality referred to as the structure‐organization‐process (SOP) model of change. The SOP model is an ontological schema that can be utilized wherever order can be found. A case study on the periodic table and the structure of DNA provide the first insight that the model might be a general organizing principle. More case studies are required to evaluate the applicability of the SOP model. Copyright © 2009 John Wiley & Sons, Ltd.
Mobility and handoff management in vehicular networks: a survey
Authors: Zhu Kun , Niyato Dusit , Wang Ping , Hossain Ekram , In Kim Dong 
Published: October 2009

AbstractMobility management is one of the most challenging research issues for vehicular networks to support a variety of intelligent transportation system (ITS) applications. The traditional mobility management schemes for Internet and mobilead hocnetwork (MANET) cannot meet the requirements of vehicular networks, and the performance degrades severely due to the unique characteristics of vehicular networks (e.g., high mobility). Therefore, mobility management solutions developed specifically for vehicular networks would be required. This paper presents a comprehensive survey on mobility management for vehicular networks. First, the requirements of mobility management for vehicular networks are identified. Then, classified based on two communication scenarios in vehicular networks, namely, vehicle‐to‐vehicle (V2V) and vehicle‐to‐infrastructure (V2I) communications, the existing mobility management schemes are reviewed. The differences between host‐based and network‐based mobility management are discussed. To this end, several open research issues in mobility management for vehicular networks are outlined. Copyright © 2009 John Wiley & Sons, Ltd.
Security analysis and improvements of IEEE standard 802.16 in next generation wireless metropolitan access network
Authors: Xiong Naixue , Yang Fan , Li Hong‐Yan , Park Jong Hyuk , Dai Yuanshun , Pan Yi 
Published: October 2009

AbstractNext generation communications (NGC) represents advanced communication environments featuring objects that are focused on users. It is crucial to protect information and digital forensics for NGC. In this paper, we aim to address network security for NGC, including IEEE standard 802.16 that are associated with NGC utilization.The IEEE standard 802.16 is a wireless air interface technology in Wireless Metropolitan Access Network (WMAN). Now in the new era of wireless networking, it is the solution for ‘last mile’ problem. Point‐to‐MultiPoint (PMP) network architecture network mode and mesh network mode are two optional networking modes proposed in this standard. However, the security problems in its original protocol may be becoming the most serious obstacle in its marketable producing process. In this paper, explanation and analysis of the security mechanism are based on PMP and mesh networking modes, respectively. This paper focuses on authentication & authorization, which is the most important part but not explicitly defined in original security design of IEEE standard 802.16. Two improved schemes focused on authentication & authorization based on the two modes are proposed to strengthen 802.16 WMAN security, respectively. The relevant analysis and simulation results prove that our schemes are effective. Copyright © 2009 John Wiley & Sons, Ltd.
Quinoline‐n‐butylcyanoacrylate‐based nanoparticles for brain targeting for the diagnosis of Alzheimer's disease
Authors: Kulkarni Padmakar V. , Roney Celeste A. , Antich Peter P. , Bonte Frederick J. , Raghu Anjanapura V. , Aminabhavi Tejraj M. 
Published: October 2009

AbstractA survey of research activity on nanoparticles (NPs) based on polymeric devices that could cross the blood–brain barrier (BBB) is given along with the presentation of our own data on the development of NPs of n‐butyl‐2‐cyanoacrylate (BCA) for brain delivery to aid the early diagnosis of Alzeimer's disease (AD), a neurodegenerative disorder of the elderly people, the most prevalent form of dementia. Typical data are presented on in vivo detection of amyloid peptides (Aβ) (amyloid plaques) that are used as targets for developing the biological markers for the diagnosis of AD. In order to develop efficient in vivo probes, polymeric n‐butyl‐2‐cyanoacrylate (PBCA) NPs have been prepared and encapsulated with the radio‐labeled amyloid affinity drug 125I‐clioquinol (CQ, 5‐chloro‐7‐iodo‐8‐hydroxyquinoline) to improve the transport to brain and amyloid plaque retention of 125I‐CQ using the NPs of PBCA. The 125I‐CQ discriminately binds to the AD post‐mortem brain tissue homogenates versus control. 125I‐CQ‐PBCA NPs labeled the Aβ plaques from the AD human post‐mortem frontal cortical sections on paraffin‐fixed slides. Storage phosphor imaging verified preferential uptake by AD brain sections compared to cortical control sections. The 125I‐CQ‐PBCA NPs crossed the BBB in wild type mouse, giving an increased brain uptake measured in terms of % ID/g i.e., injected dose compared to 125I‐CQ. Brain retention of 125I‐CQ‐PBCA NPs was significantly increased in the AD transgenic mice (APP/PS1) and in mice injected with aggregated Aβ42 peptide versus age‐matched wild type controls. The results of this study are verified by in vivo storage phosphor imaging and validated by histopathological staining of plaques and select metal ions, viz. Fe2+ and Cu2+. The 125I‐CQ‐PBCA NPs had more efficient brain entry and rapid clearance in normal mice and enhanced the retention in AD mouse brain demonstrating the ideal in vivo imaging characteristics. The 125I‐CQ‐PBCA NPs exhibited specificity for Aβ plaques both in vitro and in vivo. This combination offered radio‐iodinated CQ‐PBCA NPs as the promising delivery vehicle for in vivo single photon emission tomography (SPECT) (123I) or PET (124I) amyloid imaging agent. The importance of the topic in relation to brain delivery and other similar type of work published in this area are covered to highlight the importance of this research to medical disciplines. WIREs Nanomed Nanobiotechnol 2010 2 35–47This article is categorized under:

Therapeutic Approaches and Drug Discovery > Nanomedicine for Neurological Disease
Complex mathematical models of biology at the nanoscale
Authors: Bewick Sharon , Yang Ruoting , Zhang Mingjun 
Published: October 2009

AbstractMathematical modeling of nanobiosystems is an exciting and rapidly growing new field of research that offers the potential to guide and improve technological developments in both nanomedicine and nanobiomaterial science. Unlike the more traditional fields of science and engineering, however, models of nanobiosystems are notoriously complex. In this paper, we highlight some of the primary sources of complexity in nanobiosystems. In particular, we focus on complexity that arises from the inherent nonlinearity of natural systems, noise generated by low copy numbers of relevant biological constituents, heterogeneity that stems from structure in physical systems at the nanoscale, strong coupling between processes that occur at different scales, and the large dimensions necessary to represent typical biological systems. We then suggest how different mathematical modeling techniques are currently being explored and developed to deal with the complicated and computationally demanding problems that can arise when modeling nanobiosystems. Although a relatively new field, mathematical descriptions of nanobiology are becoming increasingly more common and more important for both directing and interpreting experimental studies on nanobiosystems. The goal of this review is to emphasize the challenges associated with modeling nanobiosystems to inspire renewed effort in this highly interdisciplinary, but certainly rewarding, field. Copyright © 2009 John Wiley & Sons, Inc.This article is categorized under:

Nanotechnology Approaches to Biology > Nanoscale Systems in Biology
Surgical treatment of hilar cholangiocarcinoma in the “new era”: the Nagoya University experience
Authors: Igami Tsuyoshi , Nishio Hideki , Ebata Tomoki , Yokoyama Yukihiro , Sugawara Gen , Nimura Yuji , Nagino Masato 
Published: October 2009

AbstractObjectiveTo review our surgical experience with hilar cholangiocarcinoma in the “new era.”MethodsThe medical records of 428 patients with hilar cholangiocarcinoma who underwent treatment between 2001 and 2008 at the First Department of Surgery, the Nagoya University Hospital, were retrospectively reviewed.ResultsOf the 428 patients, 298 (70%) underwent surgical resection (R0,n = 220; R1,n = 70; R2,n = 8). Portal vein resection was performed in 111 (37%) patients, and hepatic artery resection was performed in 53 (18%) patients. Several different types of postoperative complications occurred in a total of 129 (43%) patients and led to 6 (2%) deaths. Of the 298 resected tumors, 206 (69%) were extrahepatic type tumors, and the remaining 92 (31%) were intrahepatic type tumors. Using the Bismuth classification criteria, we identified 15 (5%) type I, 21 (7%) type II, 120 (40%) type III, and 142 (48%) type IV tumors. The overall 1‐, 3‐, and 5‐year survival rates for all 298 patients were 77, 49, and 42%, respectively. The survival rates were highest among the 197 patients with pM0 disease who underwent R0 resection. Patients in this subgroup had a 5‐year survival rate of 52%. The 5‐year overall survival rate for the 55 patients with pM0 disease who underwent R1 resection was 32%. The survival rate for patients who had pM1 disease and/or underwent R2 resection was the worst of all the subgroups, but was nonetheless significantly better than that of patients with unresectable tumors. The survival rate for patients who underwent vascular resection and reconstruction was unexpectedly better, with 5‐year survival of >20%.ConclusionsThe surgical approach to hilar cholangiocarcinoma has become more challenging in the new era. Nevertheless, surgical outcomes have been improved, with decreased morbidity and mortality rates being observed. Long‐term survival has also steadily improved. These findings indicate that biliary surgeons should use an aggressive surgical strategy to treat this intractable disease.
Nanoparticles of Block Ionomer Complexes from Double Hydrophilic Poly(acrylic acid)-b-poly(ethylene oxide)-b-poly(acrylic acid) Triblock Copolymer and Oppositely Charged Surfactant
Authors: Peng Zhiping , Sun Yuelong , Liu Xinxing , Tong Zhen 
Published: October 2009

Abstract
The novel water-dispersible nanoparticles from the double hydrophilic poly(acrylic acid)-b-poly(ethylene oxide)-b-poly(acrylic acid) (PAA-b-PEO-b-PAA) triblock copolymer and oppositely charged surfactant dodecyltrimethyl ammonium bromide (DTAB) were prepared by mixing the individual aqueous solutions. The structure of the nanoparticles was investigated as a function of the degree of neutralization (DN) by turbidimetry, dynamic light scattering (DSL),ζ-potential measurement, and atomic force microscope (AFM). The neutralization of the anionic PAA blocks with cationic DTAB accompanied with the hydrophobic interaction of alkyl tails of DTAB led to formation of core–shell nanoparticles with the core of the DTAB neutralized PAA blocks and the shell of the looped PEO blocks. The water-dispersible nanoparticles with negative ζ-potential were obtained over the DN range from 0.4 to 2.0 and their sizes depended on the DN. The looped PEO blocks hindered the further neutralization of the PAA blocks with cationic DTAB, resulting in existence of some negative charged PAA-b-PEO-b-PAA backbones even when DN > 1.0. The spherical and ellipsoidal nature of these nanoparticles was observed with AFM.
Imaging on pelvic pyomyositis in children related to pathogenesis
Authors: Gonzalez Moran Gaspar , Garcia Duran Cristina , Albiñana Javier 
Published: October 2009

Purpose Pelvic pyomyositis in children is a rare infectious condition, although it is increasingly reported in temperate climates. Often considered a primary disease, new diagnostic methods are able to identify additional foci of infection. The purpose of this study is to review our patients and to analyze the imaging studies to determine its pathogenesis. Methods A retrospective study of the clinical charts and imaging records of 11 patients was made, noting the number and location of muscles involved, as well as bone and joint involvement. Results Besides the classical form of pelvic pyomyositis, i.e., iliopsoas pyomyositis, other muscular groups were frequently affected, often with multiple involvement. Bone involvement is also frequent. Magnetic resonance imaging (MRI) gives the most useful information. Conclusion MRI is the diagnostic procedure of choice for diagnosing pelvic pyomyositis in children. It may also have an elucidating role in the debated pathogenesis of this condition. In most of the cases, pelvic pyomyositis in children could be secondary.
ON m-COVERS AND m-SYSTEMS
Authors: SUN ZHI-WEI 
Published: October 2009

AbstractLet 𝒜={as(mod ns)}ks=0 be a system of residue classes. With the help of cyclotomic fields we obtain a theorem which unifies several previously known results related to the covering multiplicity of 𝒜. In particular, we show that if every integer lies in more than m0=⌊∑ ks=11/ns⌋ members of 𝒜, then for any a=0,1,2,… there are at least ${m_0\choose \lfloor a/n_0\rfloor }$ subsets I of {1,…,k} with ∑ s∈I1/ns=a/n0. We also characterize when any integer lies in at most m members of 𝒜, where m is a fixed positive integer.
Caledonian strike-slip terrane accretion in W. Ireland: insights from very low-grade metamorphism (illite–chlorite crystallinity and b0parameter)
Authors: RICE A. H. N. , WILLIAMS D. M. 
Published: October 2009

AbstractAnalysis of pelites with detrital white-micas in the Clew Bay–Galway Bay segment of the Irish Caledonides indicates that b0data from whole-rock and < 2 μm fractions generally show differences smaller than the errors of the method, irrespective of (001) illite crystallinity values, probably due to metamorphic recrystallization. Intermediate pressure metamorphism of the Ordovician–Silurian Clew Bay Group indicates slow subduction, allowing partial thermal re-equilibration before exhumation. In contrast, the Croagh Patrick Group Laurentian shelf-sediments underwent high-pressure alteration, suggesting rapid subduction/exhumation, synchronous with strike-slip faulting. The Murrisk Group, which underwent high-intermediate pressure metamorphism in an Ordovician back-arc, forms a separate terrane to the Croagh Patrick Group to the north and also to the Ordovician Lough Nafooey and Tourmakeady groups and Rosroe Formation in the south, in which low-intermediate pressure alteration occurred. These, together with the Silurian North Galway Group, may have undergone heating due to movement over or deposition on the hot Gowlaun Detachment as the Connemara Dalradian was exhumed. The South Connemara Group also underwent a high-pressure alteration, consistent with its inferred subduction environment. Evidence of contact alteration, due to known or inferred buried late- to post-Caledonian granitoid plutons, has been found in the Clew Bay, Louisburg–Clare Island, Croagh Patrick, Murrisk and South Connemara groups. These show evidence of lower-pressure alteration than the surrounding country-rocks.
Early Intervention Services With American Indian Tribes in New Mexico
Authors: Pedersen Mette J. , Vining Christine B. 
Published: October 2009

Abstract
Typical approaches to early intervention services, as carried out in many parts of the United States, may not be practical or successful with traditional American Indian families and communities. New Mexico, home to 22 tribes (19 pueblos, Navajo, and 2 Apache tribes) with eight indigenous languages, has worked through its Part C Family Infant Toddler (FIT) Program to support services for all communities in ways that meet community and cultural norms. This has led to examination of service delivery approaches, community based services guided by local American Indian leadership, and scrutiny of early assessment and evaluation in a culturally appropriate manner, compatible with state and federal regulation. This overview of the early intervention system, its challenges and opportunities, shares features of early intervention programs serving New Mexico tribes, and speech-language services in the context of family-centered philosophy, and culturally competent service delivery.
Between Community and Hospital: Healthcare-Associated Gram-Negative Bacteremia among Hospitalized Patients
Authors: Marschall Jonas , Fraser Victoria J. , Doherty Joshua , Warren David K. 
Published: October 2009

Objective.Healthcare-associated, community-acquired bacteremia is a subcategory of community-acquired bacteremia distinguished by recent exposure of the patient to the healthcare system before hospital admission. Our objective was to apply this category to a prospective cohort of hospitalized patients with gram-negative bacteremia to determine differences in the epidemiological characteristics, treatment, and outcome of community-acquired bacteremia; healthcare-associated, community-acquired bacteremia; and hospital-acquired bacteremia.Design.A 6-month prospective cohort study.Setting.A 1,250-bed tertiary care hospital.Patients.Adults hospitalized with gram-negative bacteremia.Results.Among 250 patients, 160 (64.0%) had bacteremia within 48 hours after admission; 132 (82.5%) of these were considered to have healthcare-associated, community-acquired bacteremia, according to previously published criteria. For patients with healthcare-associated, community-acquired bacteremia, compared with patients with community-acquired bacteremia, malignancies (59 [44.7%] of 132 patients vs 3 [10.7%] of 28 patients; P = .001), open wounds at admission (42 [31.8%] vs 3 [10.7%]; P = .02), and intravascular catheter-related infections (26 [19.7%] vs 0; P = .009) were more frequent and Escherichia coli as a causative agent was less frequent (16 [57.1%] vs 33 [25.0%]; P = .001). There was no difference between these 2 groups in inadequate empirical antibiotic treatment (36 [27.3%] vs 6 [21.4%]; P = .5) and hospital mortality (18 [13.6%] vs 2 [[7.1%]; P = .5). Compared with 90 patients with hospital-acquired bacteremia, patients with healthcare-associated, community-acquired bacteremia had a higher Charlson score (odds ratio [OR], 1.31 [95% confidence interval (CI), 1.14–1.49]) but were less likely to have lymphoma (OR, 0.07 [95% CI, 0.01–0.51]), neutropenia (OR, 0.21 [95% CI, 0.07–0.61]), a removable foreign body (OR, 0.08 [95% CI, 0.03–0.20]), or Klebsiella pneumoniae infection (OR, 0.26 [95% CI, 0.11–0.62]).Conclusions.Many cases of gram-negative bacteremia that occurred in hospitalized patients were healthcare associated. The patients differed in some aspects from patients with community-acquired bacteremia and from those with hospital-acquired bacteremia, but not in mortality.
Validation of Statewide Surveillance System Data on Central Line–Associated Bloodstream Infection in Intensive Care Units in Australia
Authors: McBryde Emma S. , Brett Judy , Russo Philip L. , Worth Leon J. , Bull Ann L. , Richards Michael J. 
Published: October 2009

Objective.To measure the interobserver agreement, sensitivity, specificity, positive predictive value, and negative predictive value of data submitted to a statewide surveillance system for identifying central line-associated bloodstream infection (BSI).Design.Retrospective review of hospital medical records comparing reported data with gold standard according to definitions of central line–associated BSI.Setting.Six Victorian public hospitals with more than 100 beds.Methods.Reporting of surveillance outcomes was undertaken by infection control practitioners at the hospital sites. Retrospective evaluation of the surveillance process was carried out by independent infection control practitioners from the Victorian Hospital Acquired Infection Surveillance System (VICNISS). A sample of records of patients reported to have a central line-associated BSI were assessed to determine whether they met the definition of central line–associated BSI. A sample of records of patients with bacteremia in the intensive care unit during the assessment period who were not reported as having central line–associated BSI were also assessed to see whether they met the definition of central line-associated BSI.Results.Records of 108 patients were reviewed; the agreement between surveillance reports and the VICNISS assessment was 67.6% (κ = 0.31). Of the 46 reported central line–associated BSIs, 27 were confirmed to be central line–associated BSIs, for a positive predictive value of 59% (95% confidence interval [CI], 43%–73%). Of the 62 cases of bacteremia reviewed that were not reported as central line–associated BSIs, 45 were not associated with a central line, for a negative predictive value of 73% (95% CI, 60%–83%). Estimated sensitivity was 35%, and specificity was 87%. The positive likelihood ratio was 3.0, and the negative likelihood ratio was 0.72.Discussion.The agreement between the reporting of central line–associated BSI and the gold standard application of definitions was unacceptably low. False-negative results were problematic; more than half of central line–associated BSIs may be missed in Victorian public hospitals.