bluuebunny/crossref_metadata_2025 huggingface dataset:
Full‐field ERG, multifocal ERG and multifocal VEP in patients with retinitis pigmentosa and residual central visual fields
Authors: Gränse Lotta , Ponjavic Vesna , Andréasson Sten
Published: December 2004

Purpose:  To evaluate (with three different electrophysiological methods) the residual retinal function in a selected group of patients with retinitis pigmentosa and remaining small central visual fields.

Methods:  Fourteen patients from several different genetic subgroups, who had been followed with visual acuity and visual field testing for periods up to 32 years, were examined. Ophthalmological examination included full‐field electroretinography (ERG), multifocal electroretinography (mfERG) and multifocal visual evoked potential (mfVEP).

Results:  The ERGs were severely reduced in all patients. The mfERGs demonstrated the residual central retinal function in five of the patients. The mfVEPs showed measurable amplitudes centrally in most of the patients. The follow‐up examinations demonstrated the slowly progressive course of the disease with preservation or only slight further loss of visual fields over a period of 7–32 years.

Conclusion:  Patients with retinitis pigmentosa may not always follow the typical natural course with progressive loss of visual fields, which may in some patients remain unaffected over several decades. Multifocal ERG and mfVEP may be clinically useful for evaluating remaining visual function in these patients.
Encouraging results of photodynamic therapy with Visudyne in a clinical patient material of age‐related macular degeneration
Authors: Frennesson Christina I. , Nilsson Sven Erik G.
Published: December 2004

Purpose:  To investigate the effects of photodynamic therapy (PDT) on subfoveal choroidal neovascularization (CNV) in age‐related macular degeneration (AMD) in a Swedish patient material with smaller lesions than those investigated in the TAP (Treatment of Age‐related Macular Degeneration with Photodynamic Therapy) and VIP (Verteporfin in Photodynamic Therapy) Studies.

Methods:  Photodynamic therapy with verteporfin was performed according to the results and recommendations of the TAP and VIP Studies. The patients were followed up for 12 months and retreatment was performed every 12 weeks when leakage from CNV was present. Of the 100 eyes in the first 100 patients with a follow‐up period of 12 months, 59% had a predominantly classic lesion, 36% had an occult‐only lesion and 5% had a minimally classic lesion. The greatest linear dimension (GLD) was ≤3 MPS (Macular Photocoagulation Study) disc diameters (DD) in 73%, 39% and 20% of lesions, respectively, for the three groups. The actual lesion area was ≤3 MPS disc areas (DA) in 85%, 50% and 40% of lesions, respectively. There was a positive correlation (p < 0.05) between the duration of symptoms and GLD, as well as between the duration of symptoms and the lesion area (p < 0.02).

Results:  At 12 months, visual acuity had remained stable or increased by ≥3 lines (ETDRS) in 61% of patients with predominantly classic lesions, in 61% of patients with occult‐only lesions and in 60% of patients with minimally classic lesions. Leakage had stopped after 2.9 ± 0.9 treatments in 77% of the total group of patients.

Conclusion:  The visual outcome was comparable to those of the TAP and VIP Studies (p > 0.3). Regarding the effect on leakage, however, our results are far better than those of the TAP and VIP Studies. The proportion of patients in which leakage had stopped was almost three times that of the TAP (27%) and VIP (26%) Studies. It seems likely that this difference was caused by the fact that the lesions in our study were much smaller, on average, than those in the TAP and VIP Studies.
Epithelial ingrowth after LASIK treatment with scraping and phototherapeutic keratectomy
Authors: Fagerholm Per , Molander Nils , Podskochy Alexander , Sundelin Staffan
Published: December 2004

Purpose:  To evaluate the effect of phototherapeutic keratectomy (PTK) in combination with manual scraping when removing epithelial ingrowth under a LASIK flap.

Material and Methods:  Three patients, who had undergone several surgeries following LASIK in order to remove epithelial ingrowth that was threatening vision, were treated with a flap lift, manual abrasion and PTK. The PTK was performed on both the stromal and the flap side with the aim of eliminating the threat and improving vision. Two patients underwent primary surgery to remove epithelial ingrowth with manual abrasion and PTK. The influence on vision, topography and cell recurrences was evaluated.

Results:  Uncorrected visual acuity (UCVA) and best spectacle‐corrected visual acuity (BSCVA) improved in four cases and remained good in the fifth case. The refraction did not change significantly. Topography disclosed changes in the irregular astigmatism, explaining the improved BSCVA. Central epithelial ingrowth did not recur, whereas peripheral ingrowth did. The peripheral ingrowth did not progress, except in case 1, where a cyst formed that required surgery.

Conclusions:  It is our belief that adding PTK to manual scraping improves the prognosis for eyes with epithelial ingrowth. It is mainly the central ingrowth that is positively affected. Improved adhesion between the stroma and the flap is one possible explanation.
Reduced thirst in patients with a vasospastic syndrome
Authors: Teuchner Barbara , Orgül Selim , Ulmer Hanno , Haufschild Timo , Flammer Josef
Published: December 2004

Purpose:  To compare thirst, drinking behaviour, and endothelin‐1 (ET‐1) plasma levels between vasospastic and non‐vasospastic subjects.

Methods:  We compared 67 subjects with a primary vasospastic syndrome with 64 age‐ and sex‐matched non‐vasospastic control subjects. A detailed medical history was recorded, including a questionnaire containing queries about thirst and drinking behaviour, history of migraine or unspecific headache, history of episodes of low blood pressure, and smoking habits. Body mass index (BMI) was calculated and blood samples were drawn for ET‐1 measurements.

Results:  Subjects with a vasospastic syndrome reported a reduced desire to drink and a lower estimated quantity of daily fluid intake, more often forgot to drink, more often had both migraine and unspecific headache, more often had episodes of low blood pressure, and had an increased plasma level of ET‐1. These features differed statistically significantly between the two groups. There was also a non‐significant trend among vasospastic subjects to smoke less and to have a smaller BMI.

Conclusion:  A reduced desire to drink is found frequently among vasospastic subjects.
Nitroxide conjugate of a thermally responsive elastin‐like polypeptide for noninvasive thermometry
Authors: Dreher Matthew R. , Elas Martyna , Ichikawa Kazuhiro , Barth Eugene D. , Chilkoti Ashutosh , Rosen Gerald M. , Halpern Howard J. , Dewhirst Mark
Published: December 2004

Hyperthermia, as an adjuvant with radiation and chemotherapy, has shown promise in the treatment of cancer. The relevant biological effects of a hyperthermia treatment are both time and temperature‐dependent, creating a need for accurate thermometry. We present a novel noninvasive thermometry modality that combines a temperature responsive biopolymer, the elastin‐like polypeptide (ELP), and nitroxide to produce an ELP‐nitroxide conjugate. When examined with electron paramagnetic resonance (EPR) spectroscopy, the ELP‐nitroxide conjugate has temperature‐dependent spectral line widths whose predictive accuracy is ∼0.3 °C (80 μM). We believe that the temperature‐dependent changes observed in the EPR spectrum are due to the combined effect of temperature, viscosity and effective radius on the rotational correlation time of the ELP‐nitroxide conjugate.
Comparison of small photon beams measured using radiochromic and silver‐halide films in solid water phantoms
Authors: Zeidan Omar A. , Li Jonathan G. , Low Daniel A. , Dempsey James F.
Published: December 2004

In this study, we compared the dosimetric properties of four of the most commonly used films for megavoltage photon‐beam dosimetry when irradiated under identical conditions by small multileaf‐collimator (MLC) defined beamlets. Two silver‐halide films (SHFs), Kodak XV2 and EDR2, and two radiochromic films (RCFs), Gafchromic HS and MD55‐2, were irradiated by MLC‐defined beamlets from a Varian linac equipped with a 120‐leaf MLC. The beamlets were delivered with the accelerator gantry set laterally ( rotation) upon a solid‐water compression film phantom at source‐to‐surface distance which was positioned with the films parallel to the beam axis. Beamlets were delivered at central axis, , and off‐axis for both leaf‐end and leaf‐side defined beamlets. The film dosimetry was performed using a quantitative optical density (OD) imaging system that was validated in a previous study. No significant differences between SHF and RCF measurements were observed in percentage depth doses, horizontal depth profiles, or two‐dimension spatial isodose distributions in both the central axis and off‐axis measurements. We found that regardless of the type of film used, RCF or SHF, a consistent data set for small beam dose modeling was generated. Previous validation studies based on the use of RCF and OD imaging system would indicate that all film produce an accurate result for small beam characterization.
Determination of the reference air kerma rate for brachytherapy sources and the related uncertainty
Authors: van Dijk Eduard , Kolkman‐Deurloo Inger‐Karine K. , Damen Patricia M. G.
Published: December 2004

Different methods exist to determine the air kerma calibration factor of an ionization chamber for the spectrum of a high‐dose‐rate (HDR) or pulsed‐dose‐rate (PDR) source. An analysis of two methods to obtain such a calibration factor was performed: (i) the method recommended by [Goetsch et al., Med. Phys. 18, 462–467 (1991)] and (ii) the method employed by the Dutch national standards institute NMi [Petersen et al., Report S‐EI‐94.01 (NMi, Delft, The Netherlands, 1994)]. This analysis showed a systematic difference on the order of 1% in the determination of the strength of HDR and PDR sources depending on the method used for determining the air kerma calibration factor. The definitive significance of the difference between these methods can only be addressed after performing an accurate analysis of the associated uncertainties. For an NE 2561 (or equivalent) ionization chamber and an in‐air jig, a typical uncertainty budget of 0.94% was found with the NMi method. The largest contribution in the type‐B uncertainty is the uncertainty in the air kerma calibration factor for isotope , , as determined by the primary or secondary standards laboratories. This uncertainty is dominated by the uncertainties in the physical constants for the average mass‐energy absorption coefficient ratio and the stopping power ratios. This means that it is not foreseeable that the standards laboratories can decrease the uncertainty in the air kerma calibration factors for ionization chambers in the short term. When the results of the determination of the reference air kerma rates in, e.g., different institutes are compared, the uncertainties in the physical constants are the same. To compare the applied techniques, the ratio of the results can be judged by leaving out the uncertainties due to these physical constants. In that case an uncertainty budget of 0.40% (coverage ) should be taken into account. Due to the differences in approach between the method used by NMi and the method recommended by Goetsch et al., an extra type‐B uncertainty of 0.9% has to be taken into account when the method of Goetsch et al. is applied. Compared to the uncertainty of 1% found for the air calibration of , the difference of 0.9% found is significant.
Removal of bone in CT angiography of the cervical arteries by piecewise matched mask bone elimination
Authors: van Straten Marcel , Venema Henk W. , Streekstra Geert J. , Majoie Charles B. L. M. , den Heeten Gerard J. , Grimbergen Cornelis A.
Published: December 2004

In maximum intensity projection (MIP) images of CT angiography (CTA) scans, the arteries are often obscured by bone. A bone removal method is presented that uses an additional, nonenhanced scan to create a mask of the bone by thresholding and dilation. After registration of the CTA scan and the additional scan, the bone in the CTA scan is masked. As the cervical area contains bones that can move with respect to each other, these bones are separated first using a watershed algorithm, and then registered individually. A phantom study was performed to evaluate and quantify the tradeoff between the removal of the bone and the preservation of the arteries contiguous to the bone. The influence of algorithm parameters and scan parameters was studied. The method was clinically evaluated with data sets of 35 patients. Best results were obtained with a threshold of and a dilation of 8 in‐plane voxels and two out‐of‐plane voxels. The mean width of the soft tissue layer, which is also masked, was approximately . The mAs value of the nonenhanced scan could be reduced from without a loss of quality. In 32 cases the bones were registered correctly and removed completely. In three cases the bone separation was not completely successful, and consequently the bone was not completely removed. The piecewise matched mask bone elimination method proved to be able to obtain MIP images of the cervical arteries free from overprojecting bone in a fully automatic way and with only a slight increase of radiation dose.
Localization of human X chromosomal mental retardation (MRX) genes in chicken and comparison with the chicken genome sequence data
Authors: Kohn M. , Kehrer-Sawatzki H. , Hameister H.
Published: December 2004

In an ongoing study human X chromosomal mental retardation genes (MRX) were mapped in the chicken genome. Up to now the homologs of 13 genes were localized by FISH techniques. Four genes from HSAXp (TM4SF2, RSK2/RPS6KA3, NLGN4, ARX) map to GGA1q13→q31, and seven genes from HSAXq (OPHN1, AGTR2, ARHGEF6, PAK3, FACL4/ACS4, FMR2, ATRX) to GGA4p. The gene-rich region of HSAXq28 proved to be much less conserved. GDI1 localized to GGA1pter and SLC6A8 to a mid-sized microchromosome. The order of the genes was determined from the newly available genome sequence data from chicken, which reveals exact colinearity between the genes in HSAXp and GGA1q13→q31, but completely scrambled gene order between the genes with common synteny from HSAXq and GGA4p. This result supports the hypothesis that the human X chromosome is a real ancient autosomal linkage group.
Genotypic Diversity among Isoniazid-Resistant Isolates of Mycobacterium tuberculosis from Rashid Hospital in Dubai, United Arab Emirates
Authors: Ahmad Suhail , Fares Esther
Published: December 2004

Objective: To perform molecular fingerprinting for strain relatedness among isoniazid-resistant Mycobacterium tuberculosis isolates recovered from tuberculosis (TB) patients in the United Arab Emirates (UAE). Materials and Methods: Thirty-two consecutive isoniazid-resistant M. tuberculosis strains isolated from TB patients (4 natives and 28 expatriates) at Rashid Hospital, Dubai, UAE were analyzed. The typing was carried out by touchdown double-repetitive-element PCR (DRE-PCR). The status of R463 or L463 polymorphism and the presence of S315T mutation in the katG gene were also determined for isolates exhibiting cluster pattern in DRE-PCR. Results: All the 32 isolates (28 from expatriate patients and 4 from UAE nationals) exhibited 21 distinct patterns in DRE-PCR with 20 of 32 isolates exhibiting unique patterns and the remaining 12 exhibiting cluster ‘A’ pattern. All the isolates (19 of 19) yielding two or more DNA fragments in DRE-PCR were unique strains. The genotypic heterogeneity among 10 of the 12 cluster isolates was suggested by the varying susceptibility of these isolates to anti-TB drugs, presence of R463 or L463 polymorphism in the katG gene and the presence or absence of S315T mutation in the katG gene. Conclusion: The genotypic diversity among isoniazid-resistant M. tuberculosis isolates mostly recovered from expatriate patients indicates that most expatriates were infected with a unique strain imported, most likely, from their country of origin and that their latent infection was reactivated in UAE.
Coagulation and Fibrinolysis Parameters in Type 2 Diabetic Patients with and without Diabetic Vascular Complications
Authors: Erem Cihangir , Hacıhasanoğlu Arif , Çelik Şükrü , Ovalı Ercüment , Ersöz H. Önder , Ukinç Kubilay , Deger Orhan , Telatar Münir
Published: December 2004

Objectives: To investigate the markers of endogenous coagulation/fibrinolysis and vascular endothelial cell function, and to assess the relationships between hemostatic parameters and diabetic vascular complications in type 2 diabetic patients. Materials and Methods: Coagulation and fibrinolysis parameters were measured in 92 type 2 diabetic patients (43 male, 49 female, mean age 50.1 ± 13.4 years) with (n = 44) and without (n = 48) vascular diabetic complications, and in 40 nondiabetic healthy subjects (20 male, 20 female, mean age 49.8 ± 15.1 years). Common lipid parameters were also measured. Results: The plasma levels of fibrinogen, antithrombin III (AT III), plasminogen activator inhibitor-1 (PAI-1), von Willebrand factor (vWF) activity and prothrombin time were found to be significantly increased in the type 2 diabetic patients compared with the healthy subjects. Glycosylated hemoglobin lc was inversely correlated with plasma protein S and activated prothrombin time. Protein C and S activities were positively correlated with plasma vWF activity, and were negatively correlated with plasma t-PA levels. vWF activity was negatively correlated with plasma t-PA levels. AT III levels were positively correlated with plasma total cholesterol levels, plasma low density lipoprotein cholesterol levels, plasma triglycerides and D-dimer levels. Plasma PAI-1 levels and factor V activity in diabetic patients with microvascular complications were significantly higher than those of the diabetic patients without microvascular complications. The plasma PAI-1 and platelet count were increased in patients with diabetic retinopathy compared with the diabetic patients without retinopathy. Plasma PAI-1 levels and factor VII activity were significantly higher in the diabetic patients with nephropathy than in diabetic patients without nephropathy. Plasma concentrations of fibrinogen and PAI-1 were significantly higher in the diabetic patients with neuropathy than the diabetic patients without neuropathy. Conclusions: The data demonstrated that patients with type 2 diabetes mellitus had a hypercoagulable state and hypofibrinolysis, thereby indicating that activation of coagulation with a reduced fibrinolytic activity may contribute to the increased risk of vascular disease in type 2 diabetic patients.
The Clinical, Radiological and Surgical Aspects of Cerebral Hydatid Cysts in Children
Authors: Tuzun Yusuf , Kadioglu Hakan Hadi , Izci Yusuf , Suma Selami , Keles Muzaffer , Aydin Ismail Hakki
Published: December 2004

A series of 13 pediatric patients underwent surgery for cerebral hydatid cysts at the Department of Pediatric Neurosurgery between 1993 and 2003. Headache and motor weakness were the main initial signs of these patients. A round cystic lesion was the characteristic appearance on computed tomography of each patient. Different cyst locations such as the liver, kidney or spleen were detected in 5 patients. Surgery using Dowling’s technique was performed in all patients as the main treatment. Intraoperative rupture and cyst recurrence were observed in only 1 patient. Subdural effusion, intraparenchymal air and hemorrhage were the main complications observed after surgery. None of the patients died after surgery. Because of its efficacy combined with excellent results, surgery is currently the method of choice in the treatment of cerebral hydatid cyst in children.
Analysis of Intracranial Volume in Apert Syndrome Genotypes
Authors: Anderson Peter J. , Netherway David J. , Abbott Amanda H. , Cox Timothy , Roscioli Tony , David David J.
Published: December 2004

Objective: Apert syndrome is caused by a mutation of the fibroblastic growth factor type 2 gene and in nearly all of the cases where the mutation has been identified it occurs in one of two adjacent sites of the gene, either position 252 or position 253. There is currently uncertainty whether a worse neurosurgical outcome occurs in association with a particular genotype. We investigated whether there were clinically subtle (but relevant) morphological differences in the craniofacial skeleton, which would result in differences in the intracranial volume, which might account for apparent differences in surgical outcome. Method: Three-dimensional CT scans of pre-operative Apert syndrome whose genotype had been identified had the intracranial volume measured using the Cavalieri estimator with correction for partial voluming effects. The values were compared to age and sex normals and then the two genotypes compared. Results: Intracranial volumes were measured for 22 cases, 16 with the 252 mutation and 6 with the 253 mutation. Conclusions: All cases except two had greater than their sex- and age-adjusted mean normal intracranial volumes. For the 252 and 253 genotypes there were no discernible differences in intracranial volumes between the two genotypes.
Polish Substantive Penal Law Against Terrorism (Selected Issues)
Authors: Indecki Krzysztof
Published: December 2004

This article studies in detail what the Polish Penal Code says about terrorism and terrorists and how just the penalties are for breaking these laws. The article analyzes the treatment of terrorism in the general and special sections of the code, paying close attention to supposed terrorism, acts committed as a precondition to terrorist acts, the terrorist act as a conventional offense, and other terrorist offenses. The author laments that there is a lack of direct regulation on these issues and discusses the various problems resulting from this lack of precision in the penal code at the beginning of 2004.
The Lack of Interactivity and Hypertextuality in Online Media
Authors: Oblak Tanja
Published: December 2004

The main focus of this article is related to the forms of mediated content that are offered in online space. Two specific aspects of new cyber-textuality are discussed - the notion of hyper-textuality and the potential of interactivity. Both characteristics are understood as new challenges that reflect specific communication potentials of the internet. In an empirical sense, the article tries to show the extent these significant forms of mediation are used in online media news. For this reason a comparison between media content in print and online media has been made. The findings reveal the lack of interactivity in practice and explore its diversity as a communication form between media producers and reader. Regarding the hypertextuality, the analysis shows the complexity of this concept, which in the realm of news media online is still maturing.
Buckling Analysis of Tri-layer Beams with Overlapped Delaminations
Authors: Msrao Parlapalli , Hao Song , Shu D.
Published: December 2004

An exact solution to the buckling behavior of tri-layer beams with two overlapped delaminations is presented for the first time. In addition, new nondimensionalized parameters, axial and bending stiffnesses and effective slenderness ratio, are introduced. The characteristic equation governing buckling is derived by using the Euler-Bernoulli beam theory, performing proper linearization and by imposing appropriate equilibrium, kinematical continuity, and boundary conditions. Results of the present method are compared with those of homogeneous beams having single and double equal delaminations reported previously, and showed an excellent agreement. A parametric study has been carried out. The buckling load varies monotonically with the normalized axial stiffness whereas it does not with the normalized bending stiffness, where a transition region is observed. The effect of spanwise delamination location on critical buckling load is discussed for a tri-layer beam of carbon/epoxy, glass/epoxy, and carbon/epoxy. The accurate solution can serve as a benchmark solution for other numerical schemes.
Conductivity of Composites Containing Anisotropic Graded Fibers
Authors: Gu G. Q. , Yu K. W.
Published: December 2004

The conductivity of two-dimensional composites with fibers of graded anisotropic materials, whose conductivity profile in the radial direction is different from that in the tangential direction, is investigated in this paper. A formalism for treating the conducting properties of graded composites with anisotropic inclusions is proposed. The three model graded fibers, whose conductivities have the power-law, linear, and exponential profiles, respectively, are studied in detail. In these cases, the potentials in the host and fiber regions are both derived analytically. The effective conductivity for these kinds of graded composites is calculated based on the analytical solutions for graded fibers.
No Effect of a Video-Based Awareness Program on the Rate of Soccer Injuries
Authors: Arnason Arni , Engebretsen Lars , Bahr Roald
Published: December 2004

Background

The injury rate in soccer is high, and effective injury prevention methods are needed.

Purpose

To test the effect of a video-based awareness program on the incidence of acute injuries in soccer.

Study Design

Randomized control trial; Level of evidence, 1.

Methods

Participants were elite male soccer players from the top 2 divisions in Iceland. Fifteen of 20 teams completed thestudy: 7 intervention teams (127 players) and 8 control teams (144 players) chosen by random. Just before the start of the 2000soccer season, the intervention teams were visited with an intervention program. The program included a 15-minutepresentation with information on the injury risk of playing elite soccer, typical injuries, and their mechanisms. Then the players workedtogether in pairs and analyzed video sequences to develop preventive strategies. The 12 video sequences were selected fromthe previous Icelandic soccer season, representing 3 typical injury mechanisms that accounted for more than half of all incidentsrecorded. During the season, team physical therapists prospectively recorded all acute injuries, and coaches recorded trainingexposure on a special form. Injury incidence was compared between groups and between the 1999 and 2000 seasons for teamsthat participated in both seasons.

Results

No difference was observed in injury incidence between the intervention (6.6 ± 0.7 injuries per 1000 player hours) andcontrol groups (6.6 ± 0.7 injuries per 1000 player hours). Furthermore, there was no difference in injury location or type.

Conclusion

The video-based injury awareness program showed no effect on injury rate.
A Systematic Approach to Magnetic Resonance Imaging Interpretation of Sports Medicine Injuries of the Knee
Authors: Sanders Timothy G. , Miller Mark D.
Published: December 2004

Magnetic resonance imaging is performed more commonly on the knee than on any other joint, and it is an excellent diagnostic tool that can aid in the evaluation of a host of sports-related injuries involving the ligaments, tendons, menisci, osseous structures, and articular surfaces. A thorough evaluation of the images, however, can be a daunting task, as the study often contains dozens of images obtained with multiple pulse sequences and in several imaging planes. A systematic approach will facilitate an accurate and timely evaluation of this complex examination and will ensure that all of the clinically relevant structures are adequately assessed. This article will provide a systematic approach to the interpretation of a magnetic resonance examination of the knee. The normal imaging appearance of each anatomical structure will be described, and the optimal pulse sequence and imaging plane for the evaluation of each structure will be discussed. Finally, the signs of injury will be described and illustrated.
Trends in Perceived Job Quality, 1989 to 1998
Authors: Handel Michael J.
Published: December 2004

There is significant controversy over recent trends in the material and intrinsic quality of jobs. Neo-Fordist theories argue that material conditions such as pay, job security, promotion opportunities, and effort requirements have deteriorated for most of the workforce. Post-Fordist theories argue that new work systems are raising levels of intrinsic rewards such as job challenge, autonomy, and cooperation and are also offering higher wages. This article tests both theories using repeated cross-sectional data from the General Social Survey. Results suggest workers’ perceptions of the quality of their jobs remained remarkably stable on most dimensions. It is possible that this reflects various obstacles to recognizing objective changes such as flexible standards of evaluation. But stability may indicate that both schools of thought overestimate the extent of recent changes.
Hemodialysis Membranes Based on Functionalized High-density Polyethylene
Authors: Abd El-Rehima Hassan. A.
Published: December 2004

Grafting vinyl acetate (VAc) and maleic anhydride (MAn) comonomer onto high-density polyethylene (HDPE) was performed by means of gamma rays. Conditions for the minimum homopolymer formation, maximum grafting yield and alternate copolymer grafts were carried out. Further chemical treatment with sodium hydroxide, hydrochloric acid, ammonium hydroxide, sulfamic acid and amino pyridine were made on the grafted membranes to increase functionality. The swelling, mechanical, solute permeability and biocompatibility properties of these copolymers were evaluated for possible application as dialysis membranes. The introduction of functional groups on HDPE membranes enhanced their hydration and transport flux. The treated grafting membranes showed improved permeability towards urea, creatinine and uric acid over the ungrafted HDPE. The permeability rate of the solutes through the membranes depended on the molecular weight and the size of the solutes. The presence of hydrophilic groups on the membranes reduced protein adsorption and enhanced membrane transport. The swelling, solute dialysis permeability and protein low affinity properties of HDPE-g-(VAc-alt-MAn) treated with sulfamic acid or 2-aminopyridine indicate potential use as hemodialysis membranes.
Generation and Storage of Electricity from Power Harvesting Devices
Authors: Sodano Henry A. , Inman Daniel J. , Park Gyuhae
Published: December 2004

The concept of capturing the normally lost energy surrounding a system and converting it into electrical energy that can be used to extend the lifetime of that system’s power supply or possibly provide an endless supply of energy to an electronic device has captivated many researchers and has brought forth a growing amount of attention to power harvesting. One of the most common methods of obtaining the energy surrounding a system is to use piezoelectric materials. Piezoelectric materials have a crystalline structure that provides a unique ability to convert an applied electrical potential into a mechanical strain or vice versa, or convert an applied strain into an electrical current. The latter of these two properties allows the material to function as a power harvesting medium. In most cases the piezoelectric material is strained through the ambient vibration around the structure, thus allowing a frequently unused energy source to be utilized for the purpose of powering small electronic systems. However, the amount of energy generated by these piezoelectric materials is far smaller than that needed by most electronic devices. For this reason, the methods of accumulating and storing the energy generated, until sufficient power has been captured, is the key to developing completely self-powered systems. This article quantifies the amount of energy generated by a piezoelectric plate and investigates two methods of accumulating the energy thus produced. The first method uses a capacitor, which in early research has been the most common method of storing the energy generated and the second utilizes rechargeable nickel metal hydride batteries. The advantages of each method are discussed and the rechargeable battery is found to have more desirable qualities for power harvesting than the capacitor. Additionally, this manuscript represents, for the first time, the fact that the power output by a piezoelectric material is capable of recharging a discharged battery. Through the excitation of a piezoelectric plate, it is demonstrated that a 40 mAh battery can be charged in less than half an hour at resonance and in only a few hours with a random signal similar to that of a typical vibrating piece of machinery.
A New Kind of Self-coupled Electrorheological Damper and its Vibration Character
Authors: Zhao Xiao P. , Liu S. , Tang H. , Yin Jian B. , Luo Chun R.
Published: December 2004

The design and manufacture of a second-generation adaptive damper composed of an electrorheological (ER) fluid, and piezoelectric ceramics is presented in this paper. Compared with the first-generation dampers, there are three aspects of modification adopted in the design of this. These include (a) the number, mode of arrangement, and electrocircuit connecting style of piezoceramics, (b) load applying mechanism, and (c) hole-channel in the concentric cylinder electrode. The experiment conducted shows that the amplitude of frequency response function decreases drastically in the frequency range of 220-250 Hz under an exciting acceleration amplitude of 3.5 g (g the gravitational acceleration) and the resonance frequency moves from 198 to 208 Hz. The new damper excels the old one in antivibration performance. In the on-off state model, numerical simulations clearly show the vibration suppression effect of the damper. The design method of combining the ER fluid and the piezoelectric ceramic as a self-coupled system can be implemented extensively in other control systems, such as acoustic insulation and control.
Extension of Euler’s Problem to Axially Graded Columns: Two Hundred and Sixty Years Later
Authors: Elishakoff I. , Endres J.
Published: December 2004

A closed-form solution is obtained for the mode shape and the buckling load of an axially graded column that is clamped at one end and subjected to a concentrated load at the other. A semi-inverse method is employed to obtain the spatial distribution of the elastic modulus variation. A remarkable conclusion is reached on the existence of three columns with different elastic modulus variations, with the same analytical expression of the buckling load. The mode shape of one of the columns is represented by a rational expression while the other two involve irrational numbers.
Accommodating Type 2 Diabetes in the Chinese American Family
Authors: Chesla Catherine A. , Chun Kevin M.
Published: December 2004

In this interpretive study, the authors aimed to describe family responses to type 2 diabetes in Chinese Americans as reported by persons with diabetes (PWD) and spouses. Twenty participants representing 16 families completed multiple group interviews. The authors elicited positive and difficult diabetes care narratives and conducted narrative and thematic analysis of transcribed interview texts. Accommodation, the key family response, comprised the enactment of social concerns and practices to balance quality of life for individuals and families with quality of diabetes care. PWDs’ accommodation included negotiating disease disclosure, protecting the family’s meals, and maintaining ease in family relations despite diabetes symptoms. Accommodation by family members included developing shared diabetes care practices and indirect approaches to disagreements about diabetes management.
Research Streams in Rater Self-Efficacy
Authors: Bernardin H. John , Villanova Peter
Published: December 2004

We report two studies using different methodologies to advance research in the understanding of rater self-efficacy. In the first study, an experimental investigation of the effects of a program designed to augment rater self-efficacy perceptions found that student raters provided with Self-Efficacy Training for Raters (SET-R) produced less elevated ratings subsequent to training as well as reported lower levels of performance appraisal discomfort based on responses to the Performance Appraisal Discomfort Scale (PADS). We also report the survey results conducted with appraisal participants develop a rater self-efficacy scale with high fidelity to actual appraisal situations. Accordingly, appraisal circumstances that heighten the threat appraisal of raters are described by four discrete behavioral dimensions. Two super ordinate dimensions that exhibited significant differences between more and less experienced raters may suffice for a simpler representation of the rater self-efficacy domain. These findings hold promise for advancing efforts in understanding rater self-efficacy.
The Victimization of Children and Youth: A Comprehensive, National Survey
Authors: Finkelhor David , Ormrod Richard , Turner Heather , Hamby Sherry L.
Published: December 2004

This study examined a large spectrum of violence, crime, and victimization experiences in a nationally representative sample of children and youth ages 2 to 17 years. More than one half (530 per 1,000) of the children and youth had experienced a physical assault in the study year, more than 1 in 4 (273 per 1,000) a property offense, more than 1 in 8 (136 per 1,000) a form of child maltreatment, 1 in 12 (82 per 1,000) a sexual victimization, and more than 1 in 3 (357 per 1,000) had been a witness to violence or experienced another form of indirect victimization. Only a minority (29%) had no direct or indirect victimization. The mean number of victimizations for a child or youth with any victimization was 3.0, and a child or youth with one victimization had a 69% chance of experiencing another during a single year.
The Show Must Go On
Authors: Giusta Marina Della , Scuriatti Laura
Published: December 2004

This article presents an interdisciplinary analysis of the glamorization of the courtesan image as proposed by Baz Luhrmann’s film Moulin Rouge. The film sparked the appearance of high-street fashion inspired by the image of the 19th-century Parisian courtesan, which prompted the authors to examine how and why such images might appeal to female consumers. The critical analysis reaches beyond the images themselves to identify and discuss the modes of circulation of such images, and their function in achieving both the material ends of capitalism (ever-increasing consumption and production) and the promotion of one of the system’s core values (patriarchy). Moreover, the article hopes to illustrate the possibilities offered by integrating cultural and structural analyses of current social phenomena.
How Dissociated Are Implicit and Explicit Racial Attitudes? A Bogus Pipeline Approach
Authors: Nier Jason A.
Published: December 2004

The current study examined the implicit and explicit attitudes of White Americans toward African-Americans. A variation of the Bogus Pipeline procedure was employed to determine if the apparent dissociation between implicit and explicit measures of racial attitudes that is reported in previous research might be exaggerated. The results indicated that the relationship between implicit and explicit attitudes was only significant under Bogus Pipeline conditions, while implicit and explicit attitudes were largely dissociated when they were measured under normal circumstances. Thus, it appeared that as the motivation to accurately report explicit attitudes increased, the implicit-explicit relationship strengthened and the dissociation between implicit and explicit racial attitudes was substantially reduced. The results indicate that Whites’ implicit and explicit attitudes toward African-Americans may not be as greatly dissociated as some theories of racial attitudes have presumed.
For and Against: Perceived Entitativity of Supportive and Oppositional Opinion Groups
Authors: Askevis-Leherpeux Françoise
Published: December 2004

It is argued that self-labeling of opinion groups as holding ‘for’ or ‘against’ attitudes influences perceived entitativity of such groups. Based on literature on positivity biases and Moscovici’s analysis of social change (1976), we predicted that individuals may associate support with nomicity, and should perceive supportive groups as more entitative than oppositional ones. In three studies, participants rated the entitativity of supportive and oppositional groups varying in extremity and homogeneity. The first two studies showed that support was associated with greater entitativity than opposition, but only in the case of extreme opinions. They also replicated past findings that extremity and homogeneity increase perceived entitativity. A third study showed that activating an intergroup context did not lead to an ingroup-outgroup effect, but suggested that the joint effects of favorability and extremity depend on how well-defined opinions the groups are supposed to have.
Positive Mood and the Perception of Variability Within and Between Groups
Authors: Stroessner Steven J. , Mackie Diane M. , Michalsen Venezia
Published: December 2004

Three experiments investigated the effects of positive mood on perceptions of variability within and between groups. Participants formed impressions of two different and highly variable groups under a neutral or positive mood. When participants expected to learn about both groups, positive mood increased perceived intergroup similarity but did not affect perceived intragroup variability. In contrast, when participants expected to learn about only one group, judgments of intergroup and intragroup similarity were both affected by mood. Mood and the intergroup context influenced the nature and degree of information processing and resultant judgments of variability in social groups.
Parallel β-sheet as a Novel Template for Polymerization of Diacetylene
Authors: Mori Takeshi , Shimoyama Kenji , Fukawa Youichi , Minagawa Keiji , Tanaka Masami
Published: December 2004

The peptide having diacetylene at its side group formed parallel β-sheet structure in crystalline solid, and solid-state polymerization of the diacetylene groups successfully occurred by UV irradiation or heating of the crystal.
An Approach towards Nano-size Crystals of Poly(acrylic acid): Polymerization Using Layered Double Hydroxides as Template
Authors: Wang Ge , Cai Fuli , Si Lichun , Wang Zhiqiang , Duan Xue
Published: December 2004

A new approach has been proposed and was shown to be a feasible method to produce nanosized polymer crystals of poly(acrylic acid). The new approach involves in situ polymerization of acrylic acid in the interlayers of a layered double hydroxides (LDHs) followed by exchange of the polymer anion for carbonate. The key is the use of LDHs as a template.
A Highly Selective and Sensitive Fluorescent Chemosensor for Fe3+ in Physiological Aqueous Solution
Authors: Hua Jun , Wang Yan-Guang
Published: December 2004

A novel fluorescent chemosensor in which two aza-18-crown-6 moieties are linked to a coumarin fluorophore has been synthesized for sensing Fe3+. The selective fluorescence enhancement was observed upon binding Fe3+ at physiological conditions (pH = 7.4, [NaCl] = 0.135 M, [KCl] = 0.01 M), whereas other metal ions, such as Li+, Na+, K+, Mg2+, Ca2+, Cu2+, Zn2+, Co2+, Ni2+, Mn2+, Hg2+ and Pb2+ produced no effect.
Nuclear export of metazoan replication-dependent histone mRNAs is dependent on RNA length and is mediated by TAP
Authors: ERKMANN JUDITH A. , SÀNCHEZ RICARDO , TREICHEL NATHALIE , MARZLUFF WILLIAM F. , KUTAY ULRIKE
Published: December 2004

Replication-dependent histone mRNAs are the only metazoan mRNAs that are not polyadenylated, ending instead in a conserved stem–loop sequence. Histone pre-mRNAs lack introns and are processed in the nucleus by a single cleavage step, which produces the mature 3′ end of the mRNA. We have systematically examined the requirements for the nuclear export of a mouse histone mRNA using the Xenopus oocyte system. Histone mRNAs were efficiently exported when injected as mature mRNAs, demonstrating that the process of 3′ end cleavage is not required for export factor binding. Export also does not depend on the stem–loop binding protein (SLBP) since mutations of the stem–loop that prevent SLBP binding and competition with a stem–loop RNA did not affect export. Only the length of the region upstream of the stem–loop, but not its sequence, was important for efficient export. Histone mRNA export was blocked by competition with constitutive transport element (CTE) RNA, indicating that the mRNA export receptor TAP is involved in histone mRNA export. Consistent with this observation, depletion of TAP from Drosophila cells by RNAi resulted in the restriction of mature histone mRNAs to the nucleus.
Structure–function analysis of the yeast NAD+-dependent tRNA 2′-phosphotransferase Tpt1
Authors: SAWAYA RANA , SCHWER BEATE , SHUMAN STEWART
Published: December 2004

Tpt1 is an essential 230-amino-acid enzyme that catalyzes the final step in yeast tRNA splicing: the transfer of the 2′-PO4 from the splice junction to NAD+ to form ADP-ribose 1″-2″cyclic phosphate and nicotinamide. To understand the structural requirements for Saccharomyces cerevisiae Tpt1 activity, we performed an alanine-scanning mutational analysis of 14 amino acids that are conserved in homologous proteins from fungi, metazoa, protozoa, bacteria, and archaea. We thereby identified four residues—Arg23, His24, Arg71, and Arg138—as essential for Tpt1 function in vivo. Structure–activity relationships at these positions were clarified by introducing conservative substitutions. The activity of the Escherichia coli ortholog KptA in complementing tpt1Δ was abolished by alanine substitutions at the equivalent side chains, Arg21, His22, Arg69, and Arg125. Deletion analysis of Tpt1 shows that the C-terminal 20 amino acids, which are not conserved, are not essential for activity in vivo at 30°C. These findings attest to the structural and functional conservation of Tpt1-like 2′-phosphotransferases and identify likely constituents of the active site.
Decagonal quasicrystal of a new structural type
Authors: Balanetskyy Sergiy , Grushko Benjamin , Velikanova Tamara Ya.
Published: December 2004

A stable decagonal phase of a new structural type was discovered in Al—Pd—Re. This is the second Al-based alloy system after Al—Pd—Mn where both stable icosahedral and decagonal phases are formed. In contrast to the isostructural icosahedral phases of similar Al and Pd concentrations in both systems, the new decagonal phase exhibits periodicity of ∼2.57 vs. ∼1.25 nm in Al—Pd—Mn and is formed at significantly higher Al concentration than that in Al—Pd—Mn. In the tenfold plane, the structural unit of the Al—Pd—Re decagonal phase assumed from the high-resolution electron images is τ times larger in diameter than that in Al—Pd—Mn.
Extraction and use of correlated integrated intensities with powder diffraction data
Authors: Wright Jon P.
Published: December 2004

The transformation of a powder diffraction profile into a set of correlated integrated intensities allows crystallographic calculations to be performed without modelling raw diffractometer counts. By carrying out this transformation it is possible to preserve the information about peak overlap without needing to retain the multitude of experimental details and description of the peak shape function. An implementation is described which allows problems of significant size to be tackled. Least squares refinement, issues of data quality and the generation and importance of free R-factors are discussed.
Towards EXPO2005
Authors: Altomare Angela , Caliandro Rocco , Camalli Mercedes , Cuocci Corrado , Giacovazzo Carmelo , Moliterni Anna Grazia Giuseppina , Rizzi Rosanna , Spagna Riccardo , González-Platas Javier
Published: December 2004

New procedures have been introduced in EXPO2004 (Altomare, A., Caliandro, R., Camalli, M., Cuocci, C., da Silva, I., Giacovazzo, C., Moliterni, A. G. G. & Rizzi, R. , J. Appl. Cryst. Submitted) aiming at making the solution process more straightforward, particularly for cases very resistant to the ab-initio approach.