bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential Effects of Gonadotropin-Releasing Hormone (GnRH)-I and GnRH-II on Prostate Cancer Cell Signaling and Death
Authors: Maiti Kaushik , Oh Da Young , Moon Jung Sun , Acharjee Sujata , Li Jian Hua , Bai Dong Gyu , Park Hee-Sae , Lee Keesook , Lee Young Chul , Jung Neon Chul , Kim Kyungjin , Vaudry Hubert , Kwon Hyuk Bang , Seong Jae Young
Published: July 2005

Context: GnRH is known to directly regulate prostate cancer cell proliferation, but the precise mechanism of action of the peptide is still under investigation.

Objective: This study demonstrates differential effects of GnRH-I and GnRH-II on androgen-independent human prostate cancer cells.

Results: Both GnRH-I and GnRH-II increased the intracellular Ca2+ concentration ([Ca2+]i) either through Ca2+ influx from external Ca2+ source or via mobilization of Ca2+ from internal Ca2+ stores. Interestingly, the [Ca2+]i increase was mediated by activation of the ryanodine receptor but not the inositol trisphosphate receptor. Trptorelix-1, a novel GnRH-II antagonist but not cetrorelix, a classical GnRH-I antagonist, completely inhibited the GnRH-II-induced [Ca2+]i increase. Concurrently at high concentrations, trptorelix-1 and cetrorelix inhibited GnRH-I-induced [Ca2+]i increase, whereas at low concentrations they exerted an agonistic action, inducing Ca2+ influx. High concentrations of trptorelix-1 but not cetrorelix-induced prostate cancer cell death, probably through an apoptotic process. Using photoaffinity labeling with 125I-[azidobenzoyl-d-Lys6]GnRH-II, we observed that an 80-kDa protein specifically bound to GnRH-II.

Conclusions: This study suggests the existence of a novel GnRH-II binding protein, in addition to a conventional GnRH-I receptor, in prostate cancer cells. These data may facilitate the development of innovatory therapeutic drugs for the treatment of prostate cancer.
Long-Term Follow-Up of 106 Multiple Sclerosis Patients Undergoing Interferon-β 1a or 1b Therapy: Predictive Factors of Thyroid Disease Development and Duration
Authors: Caraccio N. , Dardano A. , Manfredonia F. , Manca L. , Pasquali L. , Iudice A. , Murri L. , Ferrannini E. , Monzani F.
Published: July 2005

Background: Conflicting data have been reported on the association between interferon (IFN)-β therapy of multiple sclerosis (MS) patients and thyroid disease development.

Aims: The goals of this study are as follows: to assess the actual occurrence of thyroid dysfunction and autoimmunity during long-term IFN-β therapy; to establish the possible presence of predictive factors for thyroid dysfunction development and duration; and to suggest an effective follow-up protocol for patients receiving long-term IFN-β therapy.

Study Protocol: A total of 106 MS patients (76 women) underwent IFN-β 1a or 1b therapy for up to 84 months (median, 42 months). Thyroid function and autoimmunity were assessed at baseline and every 3–6 months throughout the treatment course.

Results: Baseline thyroid autoimmunity was detected in 8.5% of patients and hypothyroidism in 2.8%. Thyroid dysfunction (80% hypothyroidism, 92% subclinical, 56% transient) developed in 24% (68% with autoimmunity) of patients and autoimmunity in 22.7% (45.5% with dysfunction), without significant differences between the two cytokines; 68% of dysfunctions occurred within the first year. Autoimmunity emerged as the only predictive factor for dysfunction development (relative risk, 8.9), whereas sustained disease was significantly associated with male gender (P < 0.003).

Conclusions: Both incident thyroid autoimmunity and dysfunction frequently occur in MS patients during IFN-β therapy, particularly within the first year of treatment. Thyroid dysfunction is generally subclinical and transient in over than half of cases; preexisting or incident autoimmunity emerged as the only significant predictive factor for thyroid dysfunction development. Thyroid function and autoimmunity assessment is mandatory within the first year of IFN-β therapy; thereafter, serum TSH measurement only in patients with thyroid disease could be sufficient.
Stress and temperature distribution at layer interface excited by pulsed laser heating
Authors: Hosseini-Tehrani P , Eslami M. R
Published: July 2005

The stress and temperature distributions at a layer interface are important controlling factors in the crack initiation at a layer interface under laser pulse heating. In this paper, a boundary element method is presented to calculate the stresses and temperature at a layer interface considering the Green-Lindsay (GL) theory of generalized thermoelasticity. The layer absorbs the thermal energy from a pulsed laser in its surface plane. The pulse duration is of the order of the characteristic time for heat to diffuse across the layer thickness; hence heat conduction through the thickness of the layer cannot be neglected. The effects of the pulse duration and layer thickness on the stresses and temperature distributions of the layer are studied. Comparisons between the classical, Lord-Shulman, and GL theories are made.
Reliability-Based Optimization and Robust Design of a Coil Tube-Spring with Non-Normal Distribution Parameters
Authors: Zhang Y. M. , He X. D. , Liu Q. L. , Wen B. C.
Published: July 2005

This paper proposes the application of reliability-based optimization and robust design methods of a coil tube-spring. The perturbation method, the Edgeworth series, the reliability-based optimization, the reliability sensitivity technique, and the robust design method are employed to present practical and effective approaches of reliability-based optimization and robust design for coil tube-spring with non-normal distribution parameters, on the condition of the known first four moments of the original random variables. Theoretical formulae for reliability-based optimization and robust design are obtained. The respective programmes can be used to obtain the reliability-based optimization and robust design parameters of a coil tube-spring with non-normal distribution parameters accurately and quickly.
Noise Due to Firecracker Explosions
Authors: Čudina M , Prezelj J
Published: July 2005

During New Year's Eve and some festivals some people are subjected to a great number of firecracker explosions. The peak sound pressure levels, originating from the explosions, can cause annoyance, fire hazards, loss of hearing, serious personal injuries, and even deaths. The immission of a peak sound pressure level at a given location due to an individual firecracker depends mainly on its sound power, the distance from explosion, and the sound pressure distribution in the time and frequency domain. In this paper, some practical measurements have been taken over a New Year's Eve and the results were compared with other days. Special emphasis is given to statistical aspects and probability distribution function of peak sound pressure levels, originating from a great number of firecracker random explosions. Results have shown that the probability distribution closely follows the Rayleigh distribution, but when the number of explosions in unit time is high enough, it tends to a Gaussian (normal) distribution.
Vision-Based Measurement of Part Deformation and Misalignment for Deformable Cylindrical Peg-in-Hole Tasks
Authors: Kim J. Y.
Published: July 2005

For successful assembly of deformable parts, information about their deformation and possible misalignments between the holes and their respective mating parts is essential. Such information can be mainly acquired from visual sensors. In this paper, part deformation and misalignment in cylindrical peg-in-hole tasks are measured by using a visual sensing system. First, the configuration and the specifications of the system, such as resolution, are described. Next, a series of experiments to measure the position of an arbitrary point are performed and its measurement accuracy is investigated. Then, an algorithm to estimate the centre-line and deformation of a cylindrical peg and an algorithm to divide and recognize a peg and a hole separately in an image are presented. On the basis of these algorithms, a series of experiments to measure part shape as part deformation are performed. Finally, an algorithm to select two views from the four on the image plane and an algorithm to estimate the centre of an occluded hole are presented. On the basis of these algorithms, a series of experiments to measure misalignment are performed. Experimental results show that the errors in measuring part deformation are approximately less than five or seven times the standard resolution of the system, and the errors in measuring misalignment are less than three or four times the standard resolution. Thereby, the system and the proposed algorithms are effective in measuring part deformation and misalignment and will dramatically increase the success rate in deformable assembly operations.
Gold-nanoparticle-dispersed Boron-doped Diamond Electrodes for Electrochemical Oxidation of Oxalic Acid
Authors: Ivandini Tribidasari A , Naono Yasutomo , Nakajima Atsushi , Einaga Yasuaki
Published: July 2005

Electrochemical behavior of gold-nanoparticle-dispersed diamond electrodes have been studied for the oxidation of oxalic acid in phosphate buffer solution. Comparison is made with gold, as-deposited diamond and gold-implanted diamond. The electrodes combine the high catalytic activity of gold and the low background current of diamond electrodes. Moreover, the electrodes can overcome the problem of stability as it is found when using other electrodes.
Recycled Catalysis of a Hydrophobic Vitamin B12 in an Ionic Liquid
Authors: Shimakoshi Hisashi , Kudo Sei , Hisaeda Yoshio
Published: July 2005

Recycled use of a hydrophobic vitamin B12, heptamethyl cobyrinate perchlorate, in the dechlorination of 1,1-bis(4-chlorophenyl)-2,2,2-trichloroethane (DDT) with a visible light irradiation system containing a [Ru(II)(bpy)3]Cl2 photosensitizer was achieved using an ionic liquid as reaction medium.
Synergy Effect of Graphite Silica and TiO2 on Photocatalytic Hydrogen Production
Authors: Ikeda Miyuki , Kusumoto Yoshihumi
Published: July 2005

The photocatalytic production of hydrogen gas from water–methanol mixtures was performed in contact with a suspended mixture of titanium dioxide (TiO2) and graphite silica (GS), one of natural minerals. A drastic synergy effect for hydrogen production was found for GS in collaboration with TiO2. It is suggested that the clay fraction in GS is one of the key components for the synergy effect.
Ion-based Organic Nanoparticles: Synthesis, Characterization, and Optical Properties of Pseudoisocyanine Dye Nanoparticles
Authors: Yao Hiroshi , Ou Zhongmin , Kimura Keisaku
Published: July 2005

We demonstrate a simple and versatile method for preparing ion-based organic nanoparticles in aqueous solution. Ion association between a cationic pseudoisocyanine dye and a tetraphenylborate anion in water produced the dye nanoparticles from several tens to hundreds of nanometers. Particle size could be controlled by changing the molar ratio of the loaded anions to the dye cations.
Cyclooxygenase-2 expression in Warthin's tumour
Authors: Loy A H C , Putti T C , Tan L K S
Published: July 2005

Objectives: To determine whether cyclooxygenase-2 (COX-2) is overexpressed in Warthin's tumours, and to characterize its pattern of expression.

Methods: Twenty-one paraffin-embedded Warthin's tumour specimens were analysed by immunohistochemical staining for expression of human COX-2. Semi-quantitative analysis of the staining was performed.

Results: In all of the specimens, we found that there was overexpression of COX-2 within the epithelial component of the tumours, with no expression in the lymphoid components. There was also overexpression of COX-2 in the salivary duct system of normal parotid tissue.

Conclusions: Our results suggest that COX-2 is up-regulated in the epithelial component of Warthin's tumours. Our findings support the hypothesis that Warthin's tumours originate from heterotopic ductal epithelial cells of the parotid gland. The role of COX-2 expression in the pathogenesis of Warthin's tumours remains to be determined.
Triple-layer laryngeal closure for intractable aspiration
Authors: Mehmet Guven , Ibrahim Aladag , Ahmet Eyibilen , Yuksel Kaplan
Published: July 2005

Impaired laryngeal protective function can result in intractable aspiration, which causes recurrent life-threatening pneumonia. Several surgical operations have been developed to treat intractable aspiration. In this case, we report a successful case of triple-layer laryngeal closure, which was performed in a patient with type II diabetes mellitus and nutritional failure due to intractable aspiration that had been caused by several stroke attacks. Triple-layer laryngeal closure is a unique modified technique that combines laryngotracheal separation and glottic closure operations. The method that we performed can be done more safely in patients who have higher post-operative and general anaesthesia risks.
Post-operative Herpes simplex virus encephalitis after surgical resection of acoustic neuroma: a case report
Authors: Filipo Roberto , Attanasio Giuseppe , De Seta Elio , Viccaro Marika
Published: July 2005

Herpes simplex virus (HSV) encephalitis is a life-threatening consequence of HSV infection of the central nervous system. Although HSV encephalitis is rare, mortality rates reach 70 per cent in the absence of therapy and only a minority of individuals return to normal function. Antiviral therapy is most effective when started early, necessitating prompt diagnosis.

A case of atypical HSV encephalitis is reported. The appearance of a strong headache followed by impairment of consciousness and hypertone of arms and legs complicated the post-operative course in a 33-year-old patient who underwent surgical removal of an acoustic neuroma. Several brain magnetic resonance imaging (MRI) and computed tomography scans performed in the first week after onset of symptoms of infection did not establish a proper diagnosis. Diffusion-weighted MRI detected brain abnormalities on the fourth day after onset of symptoms, and polymerase chain reaction identification of HSV 1 DNA confirmed the diagnosis. A positive prognosis was achieved due to the decision to start specific, high-dose antiviral therapy based on clinical suspicion, before a firm diagnosis was established.
Parathyroid carcinoma: a report of two cases and a concise review and update of the literature
Authors: Babar-Craig Humera , Quaglia Alberto , Stearns Michael
Published: July 2005

Parathyroid carcinoma is very rare and when diagnosed can be difficult to treat as more than 50 per cent have persistent or recurrent disease. Patients generally present with profound symptoms of hypercalcaemia and a palpable neck mass. We describe a case of parathyroid carcinoma in primary hyperparathyroidism and a case in tertiary hyperparathyroidism in a renal dialysis patient. Most studies in the literature are retrospective but recent trends in presentation, treatment options and complications have been reviewed and are summarized in this paper.
Do English NHS waiting time targets distort treatment priorities in orthopaedic surgery?
Authors: Appleby John , Boyle Seán , Devlin Nancy , Harley Mike , Harrison Anthony , Thorlby Ruth
Published: July 2005

Objectives: To assess and quantify the impact of guarantees on maximum waiting times on clinical decisions to admit patients from waiting lists for orthopaedic surgery.

Methods: Before and after comparative study, analysing changes in waiting times distributions between 1997/8 and 2001/2 for waiting list and booked inpatients and day cases admitted for elective treatments in trauma and orthopaedics in English hospitals.

Results: The 2001/2 maximum waiting time target of 15 months did change the pattern of admissions for trauma and orthopaedic elective inpatients, with a net increase in admissions in that year, compared with 1997/8 (and over and above the 30,259 (7.6%) overall increase in all admissions) of patients who had waited around 15 months, of 9333. There was little indication that these additional admissions displaced shorter wait patients. In absolute and proportional terms, admissions increased for all waiting time categories except very short waiters – one to two weeks (an absolute fall of 2901 and a relative fall of 6591), and those waiting 40–41 weeks. The latter fall was only 111 patients in absolute terms (or 577 relative to the expected increase), however. The former much larger reduction may be an indication of clinical distortions, but it is unclear why very short wait (presumably more urgent) patients should disproportionately suffer compared with longer wait (presumably less urgent) cases. In addition, there was little indication that more minor cases usurped more major cases: 57% of the increase consisted of knee and hip replacement procedures, for example.

Conclusions: While the 2001/2 waiting times target demonstrably changed admission patterns (and was a major contribution to the reduction in long waits), the extent to which this represented significant and clinically relevant distortions is questionable given the lack of widely accepted admission criteria. However, as targets become progressively tougher, there is a need to monitor consultants' concerns more closely.
An economic analysis of implementing the SIGN third molar guideline: implications for the design and analysis of implementation studies
Authors: Tilley Colin , McIntosh Emma , Bahrami Maryam , Clarkson Jan , Deery Chris , Pitts Nigel
Published: July 2005

Objectives: To compare the cost-effectiveness of four third molar guideline implementation strategies.

Methods: Fifty-one dental practices in Scotland were randomized to one of four implementation strategies. The effectiveness of the strategies was measured by general dental practitioners' compliance with the guideline.

Results: The effectiveness of the guideline depended crucially upon the type of patient treated. In particular, for a minority of patients (14%) with no clinical signals of their 'type', the implementation strategies generate potentially large gains in evidence-based practice. However, the cost per patient of achieving these gains is large given that the costs are incurred for all patients, but benefits accrue only to a minority.

Discussion: The results show that the type of patient presenting for treatment can influence the effectiveness, cost-effectiveness and therefore policy conclusions. Consequently, the design and analysis of studies need to be sufficiently sensitive to detect subtle interaction effects. This may explain the dearth of guideline implementation trials with significant findings. The results also suggest that a more cost-effective implementation method in primary care dentistry may be to subsidize treatment conditional upon patient type.
Numerical Solution of Binary Liquid-Phase Adsorption onto Porocel Clay Using Linear, Freundlich and Langmuir Isotherms
Authors: Olafadehan Olaosebikan A. , Susu Alfred A.
Published: July 2005

A generalized mathematical model is presented to describe the process of multi-component adsorption onto porous media in fixed beds. The model was applied to the binary adsorption, without reaction, of aromatics and sulphur compounds onto a fixed bed of Porocel clay for kerosene deodorization using linear, Freundlich and Langmuir isotherms independently. A computational scheme for the solution of the model equations is presented. The scheme is based on orthogonal collocation for spatial discretization of the resulting set of coupled hyperbolic and parabolic partial differential equations for the macro-and micro-system, respectively. Michelsen's modified third-order semi-implicit Runge-Kutta method combined with step-size adjustment strategy was used to integrate the resulting 4N ordinary differential equations.

Excellent agreement between the simulated results and pilot plant data was obtained for the breakthrough profiles for the non-linear adsorption isotherms of Freundlich and Langmuir. No agreement was obtained for the linear isotherm. Also, using the Freundlich and Langmuir isotherms, the exit concentration of the less preferentially adsorbed component (aromatics) exceeded its inlet concentration to the adsorption column for a certain period. This is indicative of the behaviour of competitive multi-component adsorption: relative to aromatics, sulphur compounds are selectively adsorbed onto Porocel clay. The relationship between solid- and liquid-phase concentration profiles for the Freundlich isotherm revealed the formation of multiple adsorption layers upon the primary mono-molecular layer. Again, for the Freundlich isotherm, the structure of the profiles exhibited a highly pronounced maximum for sulphur. An experimental breakthrough time of 8 h was also predicted for both aromatics and sulphur compounds using the non-linear Freundlich and Langmuir isotherms.
Ion-Exchange and Adsorption Properties of Titania Gels Prepared from Titanous Chloride and Hydrogen Peroxide
Authors: Yacoub Nahed , Ramadan Adham R. , Ragai Jehane
Published: July 2005

A study was carried out of the uptake of Cu2+, Ni2+, Co2+ and Ca2+ cations by hydrous titanium oxides prepared at different pH values using titanous chloride as the starting material and hydrogen peroxide as the oxidizing agent. Characterization of the oxides was carried out by nitrogen adsorption and infrared studies. The oxides were found to be amphoteric in nature and exhibited an isoelectric point of 6.6. An attempt was made to elucidate the mechanism of cation uptake which does not entail a simple ion-exchange mechanism.
Experimental Investigation of the Characteristics of a Savonius Wind Turbine
Authors: Sharma K. K. , Gupta R. , Singh S. K. , Singh S. R.
Published: July 2005

Many tests have been conducted on models in a wind tunnel for an optimum configuration of a Savonius rotor wind turbine. Three types of Savonius rotor have been used (a simple Savonius rotor of mild steel, an overlapped Savonius rotor of mild steel and one overlapped Savonius rotors of aluminium). The effect of different design parameters, namely rotor shape, overlap between rotor blades was studied. The results have corroborated some of the original findings of Savonius.
Finite Element Analysis of the Cross-Section of Wind Turbine Blades; A Comparison between Shell and 2D-Solid Models
Authors: Pardo Daniel R. , Branner Kim
Published: July 2005

A very detailed 2D-solid finite element model is developed representing the load-carrying box girder of a wind turbine blade. Using typical geometrical values for the girder dimensions and public available material data, the overall cross-sectional behaviour is analysed for a simple compressive line load. The results are compared with result from similar shell models, which typically are used for practical design. Usually, good agreement between the shell models and the detailed 2D-solid model is found for the deflections, strains and stresses in regions with loads from pure bending. However, large differences can exist in regions where the loading is dominated by shear. It is found that geometrical non-linearity starts to become important when deflections are of the same order as the laminate thickness.
Performance of Doubly Fed Induction Generator (DFIG) during Network Faults
Authors: Anaya-Lara O. , Wu X. , Cartwright P. , Ekanayake J. B. , Jenkins N.
Published: July 2005

This paper addresses the dynamic modelling of large (MW) capacity Doubly Fed Induction Generators (DFIG) wind turbines using Pscad/Emtdc™ and Matlab/Simulink™. Suitable speed and reactive power controllers are implemented and described. Application studies are conducted to observe the performance of the DFIG during power system disturbances such as three-phase faults developing in different points of the network. These studies are used to determine the DFIG's fault current contribution and power converter rating required for fault ride-through capability and protection requirements. Simulations results are presented and discussed using typical turbine and network data for wind farm facilities.
Realistic Performance Requirements for Steel in Structures
Authors: Bjorhovde Reidar
Published: July 2005

Steel offers significant advantages for construction: it has high strength and stiffness and ample deformation and stress redistribution capacities for many applications, it does not crack or otherwise fracture under normal conditions, and is available in many grades and geometric forms. On the other hand, structures will be subjected to high deformation demands due to various conditions during fabrication, construction and service. A dynamically loaded structure may experience fatigue or fracture; seismic events create major deformation demands on structural members and connections; and fabrication methods such as welding require very large local deformability of the steel under certain conditions.

However, the chemical composition and metallurgical structure of steel are very complex, and the models that are used by codes to reflect the mechanical response bear little resemblance to what it will experience under actual conditions. For example, steel is anisotropic, as a result of production operations and other plastic deformation effects. Although the anisotropy normally is of no consequence, it will affect the response of the steel in many loading and deformation demand situations. For another, the behavior of steel is a function of deformation history, to the effect that it may respond as a high strength, low ductility material, given the prior occurrence of large displacements.

The paper addresses the properties of a range of structural steels, how these are incorporated into design standards and how the standards define deformation characteristics and demands. Several examples from practice illustrate the primary behavioral characteristics. However, most of today's design requirements are strength-oriented, with focus on element load-carrying and load-transfer capacities. With the current move towards performance-based design standards and especially the demands imposed by seismic and other extreme load conditions, it is clear that deformation considerations need to be better recognized and incorporated into the structural design criteria.
Steel-Concrete Composite Shell Roofs: Structural Concept and Feasibility
Authors: Teng J. G. , Wong H. T. , Wang Z. C. , Dong S. L.
Published: July 2005

This paper describes a new structural system, namely steel-concrete composite shells, for enclosing large spaces and presents test and numerical simulation results to demonstrate its feasibility. These composite shells are formed by pouring concrete on a thin stiffened steel base shell which serves as both the permanent formwork and the tensile steel reinforcement. The thin steel shell, constructed by bolting together open-topped modular units consisting of a base plate with surrounding edge plates, is a steel shell with thin stiffeners in both directions. The new system retains all the benefits of thin concrete shells, but eliminates the need for temporary formwork and minimises the required falsework. In this paper, the background to the development of this new structural system is first given, followed by a description of its structural features. Advantages of this new structural system over existing systems are next discussed. Possible failure modes of the new structural system are also outlined. Finally, a study to demonstrate the feasibility of constructing these shell roofs of large spans with very thin steel sheets and a limited amount of shoring is presented. In this feasibility study, a finite element model was developed for bolted steel arches as a conservative approximation of bolted steel shells, and was verified using results from simple connection tests. Both the connection tests and the verification of the finite element model are given in this paper before presenting the results from the parametric study.
Considering Catenary Action in Designing End-Restrained Steel Beams in Fire
Authors: Yu H. X. , Liew J. Y. Richard
Published: July 2005

When a building compartment is subjected to fire attack, there are complex interactions between the fire affected members with the surrounding members. The behaviour of the steel frame members in fire can be drastically different from that of its member in isolation. This paper studies the behaviour of steel beams with the increase of temperature from beam action phase to catenary action phase and until failure. The load bearing mechanism in the catenary action phase is discussed and the failure criterion is defined. A new ultimate limit state based on 15% maximum strain of steel material at elevated temperature is proposed to determine the ultimate load capacity of beams failed in the catenary action phase. Wide ranges of beam parameters including various beam sizes and span lengths with different degrees of end restraints are studied. Comparison of results with those obtained from nonlinear finite element analysis shows that the proposed design method could enhance the critical temperature of steel beams by over 200 °C if proper attention is given to the integrity of connections to resist the catenary force. In this respect, methods to estimate the catenary force and beam deflection are provided.
Paradoxical effects of praise and criticism: Social, dimensional and temporal comparisons
Authors: Möller Jens
Published: July 2005

Background. When developing a domain‐specific academic self‐concept, students are not restricted to social comparisons; they may also make temporal or dimensional comparisons.

Aims. The main purpose of this study was to examine whether these different types of comparison trigger paradoxical effects of praise and criticism in the sense described by Meyer (1992). University students participated in Study 1 (N=120) and Study 4 (N=83). The Study 2 sample consisted of 180 seventh to ninth grade students, and Study 3 investigated paradoxical effects with a sample of 130 elementary school students.

Methods. Participants were presented with vignettes describing the results of 2 students (social comparison condition) versus 1 student in 2 subjects (dimensional comparison) versus 1 student in 2 subsequent tests (temporal comparison). In all cases, the results were identical. Participants were then informed about a teacher's response to these results (praise vs. criticism vs. neutral response), and were asked to estimate the ability of the 2 stimulus persons.

Results. Study 1 and Study 2 revealed that dimensional, as well as social, comparisons following praise and criticism elicit paradoxical effects of perceived ability, reflected in corresponding estimations of student effort and teacher expectancies. There were no paradoxical effects following temporal comparisons. Study 3 did not reveal any paradoxical effects, thereby supporting the assumption that the occurrence of such effects depends on the level of cognitive development. Study 4 showed that the paradoxical effects found in Study 1 and 2 occur even when the sanctioned and the neutral achievement are presented independently.

Conclusions. Dimensional comparisons, which have been largely overlooked in the past, play a major role in ability inferences.
Spectroscopic Properties of Polycyclic Aromatic Hydrocarbons: Effect of Solvent Polarity on the Fluorescence Emission Behavior of Select Fluoranthene, Fluorenochrysene, Indenochrysene, and Indenopyrene Derivatives
Authors: Tucker Sheryl A. , Acree William E. , Cho Bongsup P. , Harvey Ronald G. , Fetzer John C.
Published: July 2005

Fluorescence emission behavior is reported for benz[def]indeno-[1,2,3hi]chrysene, fluoreno[2,3,4,9defg]chrysene, benz[def]indeno-[l,2,3qr]chrysene, dibenzo[a,e]fluoranthene, indeno[1,2,3cd]pyrene, naphtho[1,2b]fluoranthene, benzo[b]fluoranthene, fluoranthene, benzo-[ghi]fluoranthene, naphtho[2,1a]fluoranthene, naphtho[2,3b]fiuoranthene, benzo[k]fluoranthene, and benzo[j]fluoranthene dissolved in organic nonelectrolyte solvents of varying polarity. Results of these measurements are used to classify the various solutes as either probe or nonprobe molecules, depending upon whether measured emission intensity ratios vary systematically with solvent polarity. Also discussed are primary and secondary inner-filtering artifacts associated with selective quenching agents used to help identify/analyze polycyclic aromatic hydrocarbons (PAHs) in unknown mixtures. Inner-filtering artifacts are illustrated by examining fluorescence emission intensities of 13 “nonalternant” PAHs at different nitromethane concentrations and solution absorbances.
Diffraction-Induced Stray Light in Infrared Microspectroscopy and its Effect on Spatial Resolution
Authors: Sommer A. J. , Katon J. E.
Published: July 2005

Model experiments were conducted in an effort to quantitatively assess the extent of stray light, resulting from diffraction, in an FT-IR microscope system. The effects of stray light were studied under conditions employing different aperturing modes, aperture sizes, and wavelengths of light. Results and consequences of the findings are discussed with respect to the spatial resolution and quantitative integrity of the data obtainable in mapping analyses of multilayer polymer laminates.
Classification of Alloys with an Artificial Neural Network and Multivariate Calibration of Glow-Discharge Emission Spectra
Authors: Glick Mark , Hieftje Gary M.
Published: July 2005

Artificial neural networks were constructed for the classification of metal alloys based on their elemental constituents. Glow discharge-atomic emission spectra obtained with a photodiode array spectrometer were used in multivariate calibrations for 7 elements in 37 Ni-based alloys (different types) and 15 Fe-based alloys. Subsets of the two major classes formed calibration sets for stepwise multiple linear regression. The remaining samples were used to validate the calibration models. Reference data from the calibration sets were then pooled into a single set to train neural networks with different architectures and different training parameters. After the neural networks learned to discriminate correctly among alloy classes in the training set, their ability to classify samples in the testing set was measured. In general, the neural network approach performed slightly better than the K-nearest neighbor method, but it suffered from a hidden classification mechanism and nonunique solutions. The neural network methodology is discussed and compared with conventional sample-classification techniques, and multivariate calibration of glow discharge spectra is compared with conventional univariate calibration.
Infrared Spectral Search for Mixtures in Medium-Size Libraries
Authors: Lo Su-Chin , Brown Chris W.
Published: July 2005

A new algorithm is presented for searching medium-size infrared spectral libraries for the components in spectra of mixtures. The algorithm treats the spectra in the library as an m-component quantitative analysis problem in which each of the library spectra represents a standard mixture having a concentration of 1.0 for that component. Principal component regression (PCR) is used to reduce the dimensionality of the problem and to provide the regression coefficients for determining pseudo-concentrations or composition indices (CI) in mixtures. The PCR analysis is followed by the application of an adaptive filter to remove all similarity of the first target component from the mixture and from a selected subgroup of the library. This is followed by a second PCR analysis on the modified spectral data to identify the next target compound. If the correct target components are selected with successive applications of the adaptive filter, the residuals will approach zero. All components in five two- and three-component mixtures were correctly identified by this new Mix-Match algorithm, whereas only two of the five mixtures were completely identified by a typical dot-product search routine.
Photo-Oxidation of Cotton Cellulose Studied by FT-IR Photoacoustic Spectroscopy
Authors: Yang Charles Q. , Freeman James M.
Published: July 2005

Fourier transform infrared photoacoustic spectroscopy (FT-IR/PAS) was used to investigate the effects of ultraviolet (UV) radiation on cotton cellulose. The infrared spectroscopic data revealed that carboxylic acid was the main photo-oxidation product. It was also concluded that UV radiation was able to penetrate through the cotton fabric and caused oxidation in the bulk of the fabric. However, the highest degree of oxidation occurred in the near-surface of the fabric facing the UV radiation.
Excitation-Emission Matrix Scanning Spectrofluorometer
Authors: Senga Yasuhiro , Minami Shigeo
Published: July 2005

A compact rapid-scanning spectrofluorometer specifically designed to acquire an excitation-emission matrix (EEM) has been developed. A conventional grating monochromator is used for selecting the excitation wavelength. The induced fluorescence is monitored with the use of a variable circular interference filter. The EEM is acquired through rapid scanning of the fluorescent wavelength achieved via rotation of the filter in conjunction with slow scanning of the excitation wavelength using a computer. A Xe-arc lamp modulated at 540 Hz is used as an excitation source. The fluorescent signal is then detected by a photomultiplier tube whose output is integrated by a lock-in amplifier. The excitation flux is simultaneously monitored with the use of a quantum counter to compensate for the fluctuation of the lamp intensity. A 26 × 31 element EEM can be acquired within a minimum time of 4 min at a detection limit of 2 μg/L with the use of fluoresceine in ethanol as sample. The performance of our EEM scanning spectrofluorometer is further evaluated for other samples of different components.
Proton NMR Analysis of Octane Number for Motor Gasoline: Part II
Authors: Ichikawa M. , Nonaka N. , Takada I. , Ishimori S. , Andoh H. , Kumamoto K.
Published: July 2005

A method to evaluate the octane number of automobile gasoline by proton magnetic resonance (PMR) has been developed. Twenty-one samples, ranging in octane number from 80 to 100, were produced by preparing different blends of gasoline bases, and the dispersion of each sample in a pattern space was examined by applying the display methods, among various pattern recognition methods, to its PMR spectrum. This report concerns the result of the study, which revealed that the octane number of a given type of automobile gasoline could be visually estimated from its PMR spectrum.
Quantitative Investigation of Charge-Trapping Effects on Raman Spectra Acquired Using Charge-Coupled-Device (CCD) Detectors
Authors: Lacy W. B. , Rowlen K. L. , Harris J. M.
Published: July 2005

Changes in spectral band parameters (width, center frequency, intensity) which arise from charge-trapping artifacts in the Thomson TH 7882 charge-coupled-device (CCD) detector are reported. These parameters are measured for a Raman scattering band of carbon tetrachloride with respect to CCD geometry (parallel vs. serial binning), in the presence and absence of preflash, vs. changes in integration time (variation in detected light level). The dependence of the spectral parameters on detector temperature was also measured. The degree of charge trapping and the charge transfer efficiency were estimated from the change in peak width and intensity vs. integration time, respectively, and were found to vary with detector temperature according to an Arrhenius relationship for the serial-binning geometry; from these results, the energy barriers to charge trapping and loss in the serial register were estimated. Practical guidelines for acquisition of binned spectra with this detector are suggested.
Infrared Study of Tetraalkylureas in Dilute Solutions
Authors: Nyquist Richard A. , Luoma Davin A.
Published: July 2005

The vC=O frequency for tetraalkylureas (TAU) shifts to lower frequency, progressing in the series tetramethyl, tetraethyl, and tetrabutyl, and the strength of the intermolecular hydrogen bond between a CHCl3 proton and the C=O group increases, progressing in a series in the same order. The vC=O frequency decreases in the order hexane, carbon tetrachloride, and chloroform. The data indicate that TAU molecules exist in equilibrium with one, two, and three hydrogen-bonded complexes of CHCl3 and CCl4. These complexes, together with bulk dielectric effects of the solvent, account for the continual decrease in frequency as the mole % CCl4/C6H14, CHCl3/C6H14, or CHCl3/CCl4 increases.
Spectroscopic Behavior of Acid-Base Indicators after Immobilization on Glass Supports
Authors: Bacci M. , Baldini F. , Bracci S.
Published: July 2005

This paper describes an extensive spectrophotometric study on several acid-base indicators immobilized, by means of a silylation process, on quartz powder and on controlled pore glass. The spectrophotometric properties of the immobilized indicators are at variance with those of the free indicators with respect to pH dependence and ranges. The different behavior of both types of indicators in the liquid and immobilized phases may be explained by both a modification in the electronic structure of the indicators and a distribution of the molecules on different sites. The differences among the spectrophotometric properties of the indicators, when these are immobilized on different solid supports, can be justified by taking into account the steric hindrance and the reactivity of the indicators. Particular attention was paid to the pH-sensitive bands and their position, keeping in mind that the investigated material could possibly be used as a transducer for pH fiber-optic sensors.
Evaluation of Multielement Capability of ICP-MS
Authors: Collantes Elizabeth R. , Dunn William J.
Published: July 2005

Results obtained from an EPA multilaboratory study of the inductively coupled plasma mass spectrometry (ICP-MS) method are compared with results for graphite furnace atomic absorption spectrometry (GFAAS) for the elements As, Pb, Se, and Tl, and with results from inductively coupled plasma atomic emission spectrometry (ICP-AES) for the elements Al, Sb, Ba, Be, Cd, Ca, Cr, Co, Cu, Fe, Mg, Mn, Ni, K, Ag, Na, V, and Zn. A representative matrix set of 6 waters, 10 soils, and a predigested group of 18 samples was used. A complete two-way analysis of variance was carried out. The statistical study indicates that analytical concentrations averaged over all ICP-MS laboratories agree with those of the reference methods for a number of the elements in each matrix set. There is highly significant variation among laboratories, but replicate determinations within laboratories are satisfactory. The methods show poor agreement with reference values for samples with low analyte concentrations. Detection capabilities for ICP-MS are greater for most elements, and the proportion of outliers is comparable. Moreover, a separate analysis of variance comparing the two types of ICP-MS instruments indicates disagreement of results for some of the elements.
Infrared Study of Dimethylacetamide in Chloroform and/or Carbon Tetrachloride 1% Solutions
Authors: Nyquist Richard A. , Luoma Davin A.
Published: July 2005

In carbon tetrachloride and/or chloroform solutions, the behavior of the carbonyl stretching mode, vC=O, versus mole % CHCl3/CCl4 can be explained on the basis of the bulk dielectric effect of the solvent system and the existence of hydrogen-bonded complexes between solute and solvent and between solvent molecules.
Effects of High-Pressure Buffer Gases on Emission from Laser-Induced Plasmas
Authors: Owens Mitch , Majidi Vahid
Published: July 2005

A laser-induced plasma is used for atomization, ionization, and excitation of elements in solid samples. The analytes are placed in a variable-pressure chamber in which the surrounding gas can be modified to obtain optimum emission characteristics for a particular sample. A time-resolved system is described which can produce qualitative and semi-quantitative spectroscopic information using a single laser plasma. The effects of the plasma position relative to the sample, the chamber pressure, and the characteristics of the surrounding gases are studied. When helium was employed as the buffer gas, maximum emission intensity for the aluminum ionic transition at 281.6 nm was observed. The spectra obtained show that it is possible to obtain qualitative spectroscopic information with the formation of single plasmas by the use of time resolution. It is also demonstrated that sample excitation can be achieved directly by the plasma and indirectly by energy transfer from gases in the chamber. This method allows the use of small sample quantities with little sample preparation and is especially advantageous for solid samples which are not easily dissolved.
Holographic Notch Filter for Low-Wavenumber Stokes and Anti-Stokes Raman Spectroscopy
Authors: Yang Bijun , Morris Michael D. , Owen Harry
Published: July 2005

A holographic notch filter with a 15-nm rejection band is used as a Rayleigh line filter for Raman spectroscopy with a single-stage grating spectrograph. The filter is shown to allow acquisition of Stokes and anti-Stokes spectra as close as 72 cm−1 from the exciting line.
Time-Resolved Spectroscopy with Fourier Transform Spectrometers: Maintaining the Fellgett Advantage
Authors: McWhirter J. T. , Sievers A. J.
Published: July 2005

It is shown how the relative white light and IR zero path signals can be adjusted on FT-IR interferometers which share common optics for the two beams so that the full Fellgett advantage is recovered for time-resolved spectra. Time-resolved KBr:CN− vibrational fluorescence spectra in the electronic ground state are used to illustrate the improved measurement technique.
Influence of the Generator Frequency on the Analytical Characteristics of FAPES
Authors: Sturgeon R. E. , Willie S. N. , Luong V. T. , Dunn J. G.
Published: July 2005

A preliminary study of the influence of generator frequency on the operating and analytical characteristics of atmospheric-pressure rf He and Ar plasmas in a FAPES (Furnace Atomization Plasma Emission Spectrometry) system is presented. Apparent forward powers of 50 W were used to establish He plasmas at 13.6,27,40, and 54 MHz and Ar plasmas at 27 and 40 MHz. He and Ar excitation temperatures were of comparable magnitude (∼3400 K) and exhibited a monotonic increase with operating frequency. Both plasmas produced complex background structure due to excitation of molecular impurities. Significant was the presence of carbon-containing molecules (CN, C2) in the Ar plasma as a result of its enhanced sputtering capabilities. Analyte sensitivity increased with frequency, but detection limits were frequency independent. Sensitivities (peak height and area) for Ag, Cu, Mn, Pb, Ni, and Fe were consistently greater in the Ar plasma.
Single- and Double-Resonance Atomic Fluorescence Spectrometry with Inductively Coupled Plasma Atomization and Laser Excitation
Authors: Simeonsson Josef B. , Ng Kin C. , Winefordner James D.
Published: July 2005

Dye lasers pumped by an XeCl excimer laser were used to excite metal atoms in the inductively coupled plasma (ICP) for single- and double-resonance fluorescence spectrometry. The detection limits (3 σ) obtained with the single-resonance approach for Ag(I), Au(I), Co(I), Ni(I), Pb(I), Pd(I), Pt(I), and Sc(II) were 0.8, 4.2, 15, 3, 5, 0.7, 3.9, 3.3, and 0.2 ng/mL respectively; and with the double-resonance approach were 1.7, 6.0, 530, 5, 170, 8, 45, 29, and 13 ng/mL, respectively. Silver and lead were determined in an unalloyed copper standard reference material (#498) by both approaches, and excellent agreement with the true values was found.