bluuebunny/crossref_metadata_2025 huggingface dataset:
Artificial neural network as a predictive tool for emissions from heavy-duty diesel vehicles in Southern California
Authors: Hashemi N , Clark N. N.
Published: August 2007

An artificial neural network (ANN) was trained on chassis dynamometer data and used to predict the oxides of nitrogen (NO x), carbon dioxide (CO2), hydrocarbons (HC), and carbon monoxide (CO) emitted from heavy-duty diesel vehicles. Axle speed, torque, their derivatives in different time steps, and two novel variables that defined speed variability over 150 seconds were defined as the inputs for the ANN. The novel variables were used to assist in predicting off-cycle emissions. Each species was considered individually as an output of the ANN. The ANN was trained on the Highway cycle and applied to the City/Suburban Heavy Vehicle Route (CSHVR) and Urban Dynamometer Driving Schedule (UDDS) with four different sets of inputs to predict the emissions for these vehicles. The research showed acceptable prediction results for the ANN, even for the one trained with only eight inputs of speed, torque, their first and second derivatives at one second, and two variables related to the speed pattern over the last 150 seconds. However, off-cycle operation (leading to high NO x emissions) was still difficult to model. The results showed an average accuracy of 0.97 for CO2, 0.89 for NO x, 0.70 for CO, and 0.48 for HC over the course of the CSHVR, Highway, and UDDS.
A study of the dimethyl ether spray characteristics and ignition delay
Authors: Kim Y , Lim J , Min K
Published: August 2007

The characteristics of the spray behaviour and ignition delay of dimethyl ether (DME) were investigated in both experiment and simulation. DME spray images were taken in a constant-volume vessel by using Mie scattering and shadowgraph methods to measure the spray tip penetration and the spray angle of the liquid and vapour phase. The images were acquired at low- and high-temperature conditions and it was found that the spray development was dependent on the ambient density. The ignition delay of DME spray was also measured under high pressure and temperature conditions and compared with that of diesel spray in the same conditions.

To predict the ignition and combustion characteristics of DME, a reduced chemical kinetic mechanism consisting of 28 species and 45 reactions was derived from a detailed mechanism. Calculated results in homogeneous conditions agreed well with the measured data from shock tube experiments. Then three-dimensional simulation of spray development and ignition delay of DME spray was performed using a flamelet model associated with a computational fluid dynamics (CFD) code and the reduced chemical kinetic mechanism. The results showed good agreement with the above experimental results.
Stress and fatigue analysis of a bow-door arm
Authors: Karlsson U , Ulfvarson A , Johnson E , Kjell G
Published: August 2007

Bow-door systems are designed according to the class rules, of which the IACS UR S8 rules serve as a base. Even though bow-door arms, with the purpose of carrying the bow-doors in an open position, are subjected to some dynamic loads, they are dimensioned according to static loads. On one ferry, a large crack arose in one of the bow-door arms. If the arm had cracked off completely, the bow-door would probably have been lost at sea, as the arm was part of the locking arrangement.

This analysis has been carried out in order to analyse whether arms, dimensioned according to a static load, should be allowed to be a part of the locking arrangements of bow-doors. The analysis was carried out with field measurements, in the form of strain and acceleration measurements on an arm during the different load cases it is subjected to. The measured results were applied on a finite element model of the arm in order to find the stress and stress ranges everywhere in the arm during the different load cases. With this information, areas subjected to large stress ranges were identified for which fatigue calculations were carried out.

None of the load cases proved to give rise to any serious fatigue, except for the bow propellers, which, in certain situations, excite the arms into resonance cycling. The resonance gives rise to a great number of stress cycles with amplitudes large enough to cause fatigue failure.
An experimental investigation of hydrodynamic damping due to vertical baffle arrangements in a rectangular tank
Authors: Younes M F , Younes Y K , El-Madah M , Ibrahim I M , El-Dannanh E H
Published: August 2007

The present work is concerned with an experimental study of the hydrodynamic damping provided by using vertical baffles in partially filled rectangular tanks. The damping ratio is evaluated for different vertical baffle dimensions, shapes, numbers, and arrangements. A small-scale test rig consisting of a partially filled rectangular tank with a pendulum suspension is designed and constructed to measure the transient responses of the system. The baffles are fitted to attenuate the lateral motion of the liquid slosh. Lower mounted and upper mounted vertical baffles of different heights and numbers are tested. Lower mounted vertical baffles with holes of different sizes and numbers are considered. Finally, the effect of a combination between upper, lower, and holed vertical baffles on the system damping is investigated. The results show that the size and location of the vertical baffles significantly influence the hydrodynamic damping. In general, the damping ratio increases as the tip of the lower mounted baffle plate is close to the liquid free surface and the location of the plate is close to the centre of the tank. Increasing the baffle numbers increases the damping ratio. The upper mounted vertical baffles are more suitable for a chargeable tank. The twin side upper mounted baffles and centre-holed lower mounted baffle arrangements give a maximum damping ratio.
Potential seasonal predictability of the observed Euro‐Atlantic atmospheric variability using SST forced ECHAM4‐T42 simulations
Authors: Friederichs P. , Frankignoul C.
Published: August 2007

To estimate the potential seasonal predictability of the Euro‐Atlantic atmospheric variability, canonical correlation analysis is used, and a comparison is made between the NCEP reanalysis with ensemble simulations of ECHAM4‐T42 forced with observed sea surface temperature (SST) and sea‐ice boundaries for 1951–94 and changing CO2 concentration. The method identifies those atmospheric modes of variability that have similar temporal evolution in the observations and the ensemble mean of the simulations. Signals due to long‐term changes in the forcing were first reduced by removing a third‐order polynomial from all data.

Significant covariability in the 500 hPa geopotential height over the Euro‐Atlantic region is found from autumn to spring. The best agreement between the patterns is seen in late winter, where a mixed Pacific–North America (PNA) and tropical/northern‐hemisphere teleconnection pattern is the dominant signal. Although it tends to modulate the North Atlantic Oscillation (NAO), the direct influence over Europe is limited. In all cases, the covariability seems to be due to remote forcing by tropical Pacific SST. However, the model response to the El Niño Southern Oscillation (ENSO) always shows a PNA pattern, while the related observed signal undergoes large seasonal changes.

The sea level pressure (SLP) over the Euro‐Atlantic region seems to be much less sensitive to remote ENSO forcing, although traces of its influence can be detected in late winter. On the other hand, a highly significant covariability is found between modelled and observed SLP anomalies in autumn, reflecting the influence of the North Atlantic SST on the NAO. However, the model does not reproduce the observed SLP structure. It is also shown that the reproducibility of the NAO in the undetrended ECHAM4 ensemble simulations in winter that was found by Latif et al. in the same simulations is related to long‐term trends in tropical Pacific and Indian Ocean SST variability. However, its origin cannot be determined as the CO2 concentration was specified from the observations in the simulations. Copyright © 2003 Royal Meteorological Society
On a threefold classification of extratropical cyclogenesis
Authors: Plant R. S. , Craig G. C. , Gray S. L.
Published: August 2007

A recently proposed extension to the twofold extratropical cyclogenesis classification scheme of Petterssen and Smebye is discussed. A third class of extratropical cyclone (type C) is described, in which initial development is controlled by a pre‐existing upper‐level potential vorticity (PV) anomaly. In its early stages, such a system is indistinguishable from the classical type B cyclone of the Petterssen and Smebye scheme. However, subsequent development cannot be understood in terms of a co‐operative interaction of the upper‐level feature with a low‐level baroclinic zone. Rather, the cyclogenetic dynamics of type C systems are dominated by the action of strong midlevel latent heating. Such heating can generate important anomalies of PV that act to suppress the formation of a low‐level thermal anomaly and that interact destructively with the pre‐existing upper‐level feature.

Candidate type C events are identified using recently developed, height‐attributable, quasi‐geostrophic, vertical‐motion diagnostics. The application of one such diagnostic to a climatology of instantaneous cyclonic features suggests that type C events may occur with reasonable frequency. The generic behaviour of system types in the proposed threefold classification scheme is compared with the actual dynamics of some cyclones from the Fronts and Atlantic Storm‐Track EXperiment (FASTEX). The analysis is based on piecewise PV inversions and numerical simulations. This approach is able to provide a good description of a case of standard type B development, consistent with the qualitative description of Petterssen and Smebye and with the quasi‐geostrophic diagnostics. Within the same framework, two systems are discussed whose behaviours do not fit the simple A/B classification, but are consistent with the proposed type C mechanism. Copyright © 2003 Royal Meteorological Society
Nonlinear growth of singular‐vector‐based perturbations
Authors: Reynolds C. A. , Rosmond T. E.
Published: August 2007

The nonlinearity of singular‐vector‐based (SV‐based) perturbation growth is examined within the context of a global atmospheric forecast model. The characteristics of these nonlinearities and their impact on the utility of SV‐based diagnostics are assessed both qualitatively and quantitatively. Nonlinearities are quantified by examining the symmetry of evolving positive and negative ‘twin’ perturbations. Perturbations initially scaled to be consistent with estimates of analysis uncertainty become significantly nonlinear by 12 h. However, the relative magnitude of the nonlinearities is a strong function of scale and metric. Small scales become nonlinear very quickly while synoptic scales can remain significantly linear out to three days. Phase differences between the positive and negative perturbation patterns relative to each other can result in significant nonlinearities even when the basic anomaly patterns are quite similar. Thus, SVs may be qualitatively useful even when nonlinearities are large.

Post‐time forecast corrections using SV‐based pseudo‐inverse perturbations show that, despite significant nonlinear perturbation growth, the nonlinear forecast corrections are similar to the expected linear corrections, even at 72 h. When the nonlinear correction does differ significantly from the expected linear correction, the nonlinear correction is usually better, indicating that in some cases the pseudo‐inverse correction effectively suppresses error growth outside the subspace defined by the leading (dry) SVs. Because a significant portion of the nonlinear growth occurs outside of the dry SV subspace, an a priori relative nonlinearity index based on the full perturbations is not a good predictor of when pseudo‐inverse‐based corrections will be ineffective. However, one can construct a reasonable predictor of pseudo‐inverse ineffectiveness by considering the nonlinearities in the synoptic scales or in the SV subspace only. Copyright © 2003 Royal Meteorological Society
The Material with Built-in Noise-Damping
Authors: Wiman Ulf
Published: August 2007

Laminated Visco-Lam is a material with built-in noise-damping qualities that could gain significant use in the manufacture of everything from automobiles to computers and white goods.
Instrumentation and metrology for single RNA counting in biological complexes or nanoparticles by a single-molecule dual-view system
Authors: Zhang Hui , Shu Dan , Huang Faqing , Guo Peixuan
Published: August 2007

Limited by the spatial resolution of optical microscopy, direct detection or counting of single components in biological complexes or nanoparticles is challenging, especially for RNA, which is conformationally versatile and structurally flexible. We report here the assembly of a customized single-molecule dual-viewing total internal reflection fluorescence imaging system for direct counting of RNA building blocks. The RNA molecules were labeled with a single fluorophore by in vitro transcription in the presence of a fluorescent AMP. Precise calculation of identical or mixed pRNA building blocks of one, two, three, or six copies within the bacteriophage phi29 DNA packaging motor or other complexes was demonstrated by applying a photobleaching assay and evaluated by binomial distribution. The dual-viewing system for excitation and recording at different wavelengths simultaneously will enable the differentiation of different complexes with different labels or relative motion of each labeled component in motion machines.
Cloning and expression profiling of testis-expressed piRNA-like RNAs
Authors: Ro Seungil , Park Chanjae , Song Rui , Nguyen Dan , Jin Jingling , Sanders Kenton M. , McCarrey John R. , Yan Wei
Published: August 2007

Using a novel small RNA cloning method, we identified 630 piRNA-like RNAs (pilRNAs) from the mouse testis, and 498 of them are novel. These pilRNA genes were mapped to all chromosomes as 71 clusters, and the majority of them (∼84%) are derived from intergenic, intronic, and exonic sequences. One of the structural characteristics for pilRNAs is that a single locus can encode numerous homologous pilRNAs with overlapping sequences. Hundreds or even thousands of pilRNAs from a single pilRNA gene cluster are all produced from a single long transcript. Expression profiling for 64 pilRNAs revealed that ∼14% of all the pilRNAs analyzed displayed a ubiquitous expression pattern, although the majority of (∼86%) pilRNAs were preferentially or exclusively expressed in meiotic and haploid male germ cells of the testis. Our semiquantitative analyses also suggest that the testis is the organ with the highest expression of pilRNAs both in number and in abundance. The large number, high abundance, unique genomic locations, and biogenesis all suggest that pilRNAs have important regulatory roles not only in spermatogenesis but also in other biological processes.
Improved amber and opal suppressor tRNAs for incorporation of unnatural amino acids in vivo. Part 2: Evaluating suppression efficiency
Authors: Rodriguez Erik A. , Lester Henry A. , Dougherty Dennis A.
Published: August 2007

The incorporation of unnatural amino acids into proteins is a valuable tool for addition of biophysical probes, bio-orthogonal functionalities, and photoreactive cross-linking agents, although these approaches often require quantities of protein that are difficult to access with chemically aminoacylated tRNAs. THG73 is an amber suppressor tRNA that has been used extensively, incorporating over 100 residues in 20 proteins. In vitro studies have shown that the Escherichia coli Asn amber suppressor (ENAS) suppresses better than THG73. However, we report here that ENAS suppresses with <26% of the efficiency of THG73 in Xenopus oocytes. We then tested the newly developed Tetrahymena thermophila Gln amber suppressor (TQAS) tRNA library, which contains mutations in the second to fourth positions of the acceptor stem. The acceptor stem mutations have no adverse effect on suppression efficiency and, in fact, can increase the suppression efficiency. Combining mutations causes an averaging of suppression efficiency, and increased suppression efficiency does not correlate with increased ΔG of the acceptor stem. We created a T. thermophila opal suppressor, TQOpS′, which shows ∼50% suppression efficiency relative to THG73. The TQAS tRNA library, composed of functional suppressor tRNAs, has been created and will allow for screening in eukaryotic cells, where rapid analysis of large libraries is not feasible.
Diverse mechanisms and machineries for import of mitochondrial proteins
Authors: Milenkovic Dusanka , Müller Judith , Stojanovski Diana , Pfanner Nikolaus , Chacinska Agnieszka
Published: August 2007

Mitochondria are ubiquitous organelles that play an essential role in energy conversion and biosynthetic pathways in eukaryotic cells. Most mitochondrial proteins must be imported from the cytosol and sorted into one of the four mitochondrial subcompartments, the outer membrane, the intermembrane space, the inner membrane and the matrix. Studies in recent years revealed a remarkable diversity of mechanisms and machineries that are required for the import of proteins into mitochondria. At least four different pathways for the sorting and assembly of nuclear-encoded mitochondrial proteins have been identified.
Cellular expression of plasma prekallikrein in human tissues
Authors: Fink Edwin , Bhoola Kanti D. , Snyman Celia , Neth Peter , Figueroa Carlos D.
Published: August 2007

Plasma prekallikrein (PPK) is synthesised in hepatocytes and secreted into the blood, where it participates in the surface-dependent activation of blood coagulation, fibrinolysis, kinin generation and inflammation. Recently we demonstrated by quantitative RT-PCR that the human PPK gene is transcribed not only in the liver, but also in various non-hepatic human tissues at significant levels. However, up to now no reliable information is available concerning protein synthesis in the corresponding human tissues. Here we demonstrate by immunohistochemical studies that PPK or plasma kallikrein (PK) is localised in cells of different embryologically derived human tissues. In the human nephron, single cells of the distal tubules stained intensely, while the cytoplasm of cells forming proximal tubules and collecting ducts stained uniformly. PPK/PK was localised in hepatic epithelial cells of the liver, in cells of the pancreatic islet of Langerhans, in the interstitial Leydig cells of the testes, in the follicular and thecal granulosa cells of the ovary, and in the parotid gland, oesophagus, skin, respiratory tract, prostate and breast. We conclude that the cellular localisation of PPK/PK in multiple different progenitor-derived cells indicates specific cellular functions of this enzyme, in addition to its known function in the blood.
Sumoylation of the zinc finger protein ZXDC enhances the function of its transcriptional activation domain
Authors: Jambunathan Srikarthika , Fontes Joseph D.
Published: August 2007

The transcription of major histocompatibility complex class II (MHC II) genes is dependent on the co-activator protein class II trans-activator (CIITA). We have recently identified a protein known as zinc finger X-linked duplicated family member C (ZXDC) that, along with its binding partner ZXDA, forms a complex that interacts with CIITA and regulates MHC II transcription. Western blot analysis with anti-ZXDC antibodies identified two species of the ZXDC protein, one migrating near its predicted molecular mass and one with slower electrophoretic mobility. We report here that the slower migrating form is the result of sumoylation at a single lysine residue within the transcriptional activation domain of ZXDC. Three SUMO proteins (SUMO-1, -2 and -3) can modify the ZXDC protein. Multiple SUMO E3 ligase enzymes and HDAC4 can facilitate ZXDC sumoylation, and one ligase, PIASy, interacts with a specific region of the ZXDC protein. We found that sumoylation does not appear to disrupt or modulate the interaction of ZXDC with its binding partners. Rather, sumoylation of ZXDC is required for full activity of the transcriptional activation domain. Our findings suggest that sumoylation is an important regulator of ZXDC.
Molecular machinery of mitochondrial dynamics in yeast
Authors: Merz Sandra , Hammermeister Miriam , Altmann Katrin , Dürr Mark , Westermann Benedikt
Published: August 2007

Mitochondria are amazingly dynamic organelles. They continuously move along cytoskeletal tracks and frequently fuse and divide. These processes are important for maintenance of mitochondrial functions, for inheritance of the organelles upon cell division, for cellular differentiation and for apoptosis. As the machinery of mitochondrial behavior has been highly conserved during evolution, it can be studied in simple model organisms, such as yeast. During the past decade, several key components of mitochondrial dynamics have been identified and functionally characterized in Saccharomyces cerevisiae. These include the mitochondrial fusion and fission machineries and proteins required for maintenance of tubular shape and mitochondrial motility. Taken together, these findings reveal a comprehensive picture that shows the cellular processes and molecular components required for mitochondrial inheritance and morphogenesis in a simple eukaryotic cell.
Mechanisms of protein import into thylakoids of chloroplasts
Authors: Schünemann Danja
Published: August 2007

The thylakoid membrane of chloroplasts contains the major photosynthetic complexes, which consist of several either nuclear or chloroplast encoded subunits. The biogenesis of these thylakoid membrane complexes requires coordinated transport and subsequent assembly of the subunits into functional complexes. Nuclear-encoded thylakoid proteins are first imported into the chloroplast and then directed to the thylakoid using different sorting mechanisms. The cpSec pathway and the cpTat pathway are mainly involved in the transport of lumenal proteins, whereas the spontaneous pathway and the cpSRP pathway are used for the insertion of integral membrane proteins into the thylakoid membrane. While cpSec-, cpTat- and cpSRP-mediated targeting can be classified as ‘assisted’ mechanisms involving numerous components, ‘unassisted’ spontaneous insertion does not require additional targeting factors. However, even the assisted pathways differ fundamentally with respect to stromal targeting factors, the composition of the translocase and energy requirements.
Solute channels of the outer membrane: from bacteria to chloroplasts
Authors: Duy Daniela , Soll Jürgen , Philippar Katrin
Published: August 2007

Chloroplasts, unique organelles of plants, originated from endosymbiosis of an ancestor of today's cyanobacteria with a mitochondria-containing host cell. It is assumed that the outer envelope membrane, which delimits the chloroplast from the surrounding cytosol, was thus inherited from its Gram-negative bacterial ancestor. This plastid-specific membrane is thus equipped with elements of prokaryotic and eukaryotic origin. In particular, the membrane-intrinsic outer envelope proteins (OEPs) form solute channels with properties reminiscent of porins and channels in the bacterial outer membrane. OEP channels are characterised by distinct specificities for metabolites and a quite peculiar expression pattern in specialised plant organs and plastids, thus disproving the assumption that the outer envelope is a non-specific molecular sieve. The same is true for the outer membrane of Gram-negative bacteria, which functions as a permeability barrier in addition to the cytoplasmic membrane, and embeds different classes of channel pores. The channels of these prokaryotic prototype proteins, ranging from unspecific porins to specific channels to ligand-gated receptors, are exclusively built of β-barrels. Although most of the OEP channels are formed by β-strands as well, phylogeny based on sequence homology alone is not feasible. Thus, the comparison of structural and functional properties of chloroplast outer envelope and bacterial outer membrane channels is required to pinpoint the ancestral OEP ‘portrait gallery’.
A comparison of humor styles, coping humor, and mental health between Chinese and Canadian university students
Authors: Chen Guo-Hai , Martin Rod A
Published: August 2007

This research compares the structure and correlates of the Humor Styles Questionnaire (HSQ) and Coping Humor Scale (CHS) in the Chinese context with those of Canadian samples. Chinese translations of the HSQ, CHS, and Symptom Checklist 90 (SCL-90) were administered to 354 Chinese university students (M = 23.4 years of age, SD = 3.6). As in the original Canadian samples, four humor factors were found in the HSQ: Affliative, Self-enhancing, Aggressive, and Self-defeating humor, and one factor was found in the CHS. The HSQ and CHS scale reliabilities in the Chinese sample were generally acceptable. Chinese participants, as compared to Canadian norms, reported significantly lower scores on the HSQ subscales and CHS, particularly on Aggressive humor. No significant gender differences were found on the four HSQ subscales in the Chinese sample, whereas Canadian males reported more use of Aggressive and Self-defeating humor than did females. Although no gender difference was found on Coping humor in the Canadian samples, Chinese males had significantly higher scores on this scale than did females. In both the Chinese and Canadian samples, younger participants reported more use of Affliative and Aggressive humor than did older ones. Affliative, Self-enhancing, and Coping humor were negatively correlated, while Aggressive and Selfdefeating humor were positively correlated with the subscales and General Symptomatic Index of the SCL-90. Regression results indicated that mental health is more strongly related to Self-enhancing, Self-defeating, and Coping humor than Affliative and Aggressive humor. Overall, the findings support the theoretical structure and usefulness of the HSQ and CHS in the Chinese context.
Orthographic puns: The case of Japanese kyoka
Authors: Takanashi Hiroko
Published: August 2007

This paper proposes a cognitive model for processing humor in puns written in kanji (logographs) and kana (phonographs) in kyoka. Kyoka is a genre of playful Japanese poetry, and it characteristically employs puns for language play and humor. This study shows how kyoka poets manipulate the use of kanji and kana orthography to trick their readers in different ways, directing readers to different processing routes of kanji and kana puns. Kanji puns offer direct access to one particular meaning, and the discovery of another hidden meaning is a surprise. Kana puns, on the other hand, produce semantic ambiguity, and the discovery of the two meanings results from an appreciation of their incompatibility. This study adds a visual aspect to the sound aspect of puns, and demonstrates ways in which cultural resources affect their processing.
Compounding construction in Thai: Its contribution to humor
Authors: Jaroenkiatboworn Kanjana
Published: August 2007

This paper analyzes some jokes in Thai, which is an isolating language. The focus of this paper is on a linguistic construction, which has high potential for structural ambiguities in Thai, that is, noun compound. The result of this study shows that they are a good resource for constructing two types of ambiguities in Thai jokes: case relation ambiguity, which is the ambiguity of surface realization of case relation, in which a noun or noun phrase can have more than one semantic role, and class ambiguity, which is an ambiguity that causes one word class to be mistaken for another class. As researches on puns in non-inflectional languages are rarely talked of in relation to others, this work might shed light on the study of puns from a new perspective.
Diagnostic Tests for Children Who Are Referred for the Investigation of Cushing Syndrome
Authors: Batista Dalia L. , Riar Jehan , Keil Meg , Stratakis Constantine A.
Published: August 2007

OBJECTIVE. Endogenous Cushing syndrome in children is a rare disorder that is most frequently caused by pituitary or adrenocortical tumors. Diagnostic criteria have generally been derived from studies of adult patients despite significant differences in both the physiology of the hypothalamic-pituitary-adrenal axis and the epidemiology of Cushing syndrome in childhood. The purpose of this study was to identify the tests that most reliably and efficiently diagnose pituitary or adrenal tumors in a large cohort of pediatric patients with Cushing syndrome.

METHODS. A retrospective review of clinical data of children who were referred to a tertiary care center for evaluation for Cushing syndrome during the years 1997 to 2005 was conducted. A total of 125 consecutive children were studied retrospectively; 105 were found to have Cushing syndrome, which was confirmed histologically; and 20 children who did not have Cushing syndrome or any other endocrinopathy served as the control group. The following tests were performed in all children: midnight and morning cortisol, corticotropin hormone, urinary free cortisol and 17-hydroxycorticosteroid levels, ovine corticotropin-releasing hormone stimulation test, and overnight high-dosage dexamethasone suppression test. Imaging of the pituitary and adrenal glands was also obtained. The main outcome measure was the sensitivity of these parameters for the diagnosis and differential diagnosis of Cushing syndrome at 100% specificity.

RESULTS. A midnight cortisol value of ≥4.4 μg/dL confirmed the diagnosis of Cushing syndrome in almost all children, with a sensitivity of 99% and a specificity of 100%. Suppression of morning cortisol levels >20% in response to an overnight, high-dosage dexamethasone test excluded all patients with adrenal tumors and identified almost all patients with pituitary tumors (sensitivity: 97.5%; specificity: 100%).

CONCLUSIONS. Our study suggests that among children who were referred for the evaluation of possible Cushing syndrome, a single cortisol value at midnight followed by overnight high-dosage dexamethasone test led to rapid and accurate confirmation and diagnostic differentiation, respectively, of hypercortisolemia caused by pituitary and adrenal tumors.
Trivalent Live Attenuated Intranasal Influenza Vaccine Administered During the 2003–2004 Influenza Type A (H3N2) Outbreak Provided Immediate, Direct, and Indirect Protection in Children
Authors: Piedra Pedro A. , Gaglani Manjusha J. , Kozinetz Claudia A. , Herschler Gayla B. , Fewlass Charles , Harvey Dianne , Zimmerman Nadine , Glezen W. Paul
Published: August 2007

OBJECTIVE. Live attenuated influenza vaccine may protect against wild-type influenza illness shortly after vaccine administration by innate immunity. The 2003–2004 influenza A (H3N2) outbreak arrived early, and the circulating strain was antigenically distinct from the vaccine strain. The objective of this study was to determine the effectiveness of influenza vaccines for healthy school-aged children when administered during the influenza outbreak.

DESIGN/METHODS. An open-labeled, nonrandomized, community-based influenza vaccine trial was conducted in children 5 to 18 years old. Age-eligible healthy children received trivalent live attenuated influenza vaccine. Trivalent inactivated influenza vaccine was given to children with underlying health conditions. Influenza-positive illness was compared between vaccinated and nonvaccinated children. Medically attended acute respiratory illness and pneumonia and influenza rates for Scott and White Health Plan vaccinees were compared with age-eligible Scott and White Health Plan nonparticipants in the intervention communities. Herd protection was assessed by comparing age-specific medically attended acute respiratory illness rates in Scott and White Health Plan members in the intervention and comparison communities.

RESULTS. We administered 1 dose of trivalent live attenuated influenza vaccine or trivalent inactivated influenza vaccine to 6569 and 1040 children, respectively (31.5% vaccination coverage), from October 10 to December 30, 2003. The influenza outbreak occurred from October 12 to December 20, 2003. Significant protection against influenza-positive illness (37.3%) and pneumonia and influenza events (50%) was detected in children who received trivalent live attenuated influenza vaccine but not trivalent inactivated influenza vaccine. Trivalent live attenuated influenza vaccine recipients had similar protection against influenza-positive illness within 14 days compared with >14 days (10 of 25 vs 9 of 30) after vaccination. Indirect effectiveness against medically attended acute respiratory illness was detected in children 5 to 11 and adults 35 to 44 years of age.

CONCLUSION. One dose of trivalent live attenuated influenza vaccine was efficacious in children even when administered during an influenza outbreak and when the dominant circulating influenza virus was antigenically distinct from the vaccine strain. We hypothesize that trivalent live attenuated influenza vaccine provides protection against influenza by both innate and adaptive immune mechanisms.
Phytoestrogens alter cortisol and and rostenedione secretion by porcine adrenocortical cells
Authors: Kamińska Barbara , Opalka M. , Dusza Luiza
Published: August 2007

The effect of plant-derived, nonsteroidal estrogens (genistein, daidzein and biochanin A) on cortisol and androstenedione secretion by porcine adrenocortical cells was examined. Adrenals were harvested from locally slaughtered mature gilts on days 5–9 of the oestrous cycle. Adrenocortical cells were incubated with or without genistein, daidzein, biochanin A (0.5, 5, 10 or 50 μM), oestradiol (10, 50, 100 or 500 pg/mL) and ACTH (5 nM — positive control). All incubations were performed for 8 h (95% air and 5% CO
2
, 37°C). ACTH increased cortisol and androstenedione secretion. Genistein, daidzein and biochanin A suppressed cortisol output, whereas androstenedione secretion was enhanced by these phytoestrogens. In contrast, oestradiol did not alter steroid secretion by porcine adrenocortical cells, which may suggest that phytoestrogens have a non-oestrogenic mechanism of action. Therefore, phytoestrogens present in commercial forage may influence adrenocortical function in pigs by decreasing cortisol and increasing androstenedione secretion.
Evaluation of goose serum amyloid a acute phase response by enzyme-linked immunosorbent assay
Authors: Kovács Beáta , Toussaint Mathilda , Gruys E. , Fábián Ibolya , Szilágyi L. , Janan J. , Rudas P.
Published: August 2007

Serum amyloid A (SAA) is of interest as the circulating precursor of amyloid A protein, the fibrillar component of AA (secondary) amyloid deposits, and also as an extremely sensitive and rapid major acute phase protein. Serum concentrations of acute phase proteins (APPs) provide valuable information about the diagnosis and prognosis of various diseases, and thus the relevance of APPs for monitoring the health status of domestic animals is widely accepted. More importantly, the measurement of SAA concentration assists in assessing the prognosis in secondary amyloidosis, which is a common disease of geese, affecting an increasing number of animals. In the present study we introduce a highly sensitive goose-specific ELISA method for measuring SAA concentration in goose serum or plasma samples. Samples were taken from geese of the Landes Grey and Hungarian White breeds, which were stimulated for an acute phase reaction by administration of a commercially available fowl cholera vaccine containing inactivated
Pasteurella multocida
. Strong and characteristically rapid acute phase responses were measured in both breeds, peaking at approximately 24 h after inoculation. The maximum SAA concentration was 1200 μg/ml. At 72 h post-inoculation, the concentrations returned to pre-inoculation values. There was significantly (p = 0.004) less intense response in the control groups; however, a very mild increase of SAA levels was detected due to the stress inevitably caused by the sampling procedure.
Nutritional and antioxidant status of colorectal tumor patients
Authors: Regöly-Mérei Andrea , Bereczky Mihály , Arató Györgyi , Telek Géza , Pallai Zsolt , Lugasi Andrea , Antal Magda
Published: August 2007

Az oxidatív stressz a colorectalis carcinogenesis egyik rizikófaktora. A gyulladásos reakciókban aktiválódnak a leukocyták, szabad gyököket termelve mutagén és mitogén hatást kifejtve elősegítik a tumorképződést. Az elhízás, a hyperlipidaemia és a hyperinzulinaemia növeli az epithelialis sejtek energiamennyiségét, ez pedig gátolhatja a mitochondrialis elektrontranszportlánc folyamatos működését. Az utóbbi következménye a fokozott szabadgyök-képződés, ami a sejtciklus szabályozási zavarához, mutációkhoz és a károsodott sejtek kontrollálatlan szaporodásához vezethet.
Célkitűzés:
Malignus és benignus colorectalis tumorokban szenvedő betegek tápláltsági állapotának és antioxidáns-státuszuk néhány paraméterének a vizsgálata.
Módszerek:
Tápanyagbevitel számítása, antropometriai mérések (testmagasság, testtömeg, derék-, csípő-, felkarkörfogat, testtömegindex, derék-csípő hányados), szérumprealbumin-meghatározás, antioxidáns-státusz biomarkereinek vizsgálata (szuperoxid-dizmutáz-, glutation-peroxidáz aktivitás, húgysav-, albuminszint, teljes antioxidáns-státusz, szabadgyök-fogó kapacitás, oxidált-fehérje-metabolit-, malondialdehid-koncentráció).
Eredmények:
A malignus tumorban szenvedő betegek élelmi rost-, A-vitamin- és folátbevitele a kívánatos érték alatt volt, és szignifikánsan kisebb volt a szérumban a prealbumin koncentrációja. A vizsgált betegek között gyakori volt a túlsúly és az elhízás. Az antioxidáns státuszt jelző biomarkerek közül szignifikáns különbségeket találtunk a betegek és a kontrollszemélyek között a szabadgyök-fogó kapacitás, az oxidált fehérjetermékek, a malondialdehid-koncentráció és a glutation-peroxidáz-aktivitás értékeiben.
Következtetések:
Az A-vitamin és a folát elégtelen bevitele, a gyakori túlsúly, illetve elhízás, valamint az antioxidáns-státuszt jelző biomarkerek kóros értékei a vizsgált betegcsoportokban a colorectalis tumor, a tápláltsági állapot és az antioxidáns-státusz közötti összefüggéseket látszanak alátámasztani.
Depression, Hopelessness, and Sleep in Cancer Patients' Desire for Death
Authors: Mystakidou Kyriaki , Parpa Efi , Tsilika Eleni , Pathiaki Maria , Galanos Antonis , Vlahos Lambros
Published: August 2007

Objective:

The aim of this study was to evaluate the prevalence of clinical characteristics and risk factors for hastened death in advanced cancer patients.

Methods:

Patients completed the Greek version of Schedule of Attitudes toward Hastened Death (G-SAHD), a sleep quality measure, the Pittsburgh Sleep Quality Index (PSQI), a Greek version of a depression inventory, the Beck Depression Inventory (BDI), a hopelessness scale, the Beck Hopelessness Scale (BHS), and a Visual Analogue Scale (VAS) for the assessment of pain.

Patients:

The final sample consisted of 102 terminally ill cancer patients attending a Palliative Care Unit.

Results:

Statistically significant associations were found between G-SAHD and patients performance status (ECOG) (χ2 = 8.62, p = 0.003). Strongest associations were observed between desire for death, depression, and hopelessness ( r = 0.468, p < 0.0005, r = 0.678, p < 0.0005, respectively). In the prediction of G-SHAD the contribution of “hopelessness” ( p < 0.0005), “depression” ( p < 0.0005), “use of sleeping medication” ( p < 0.0005), and “sleep quality” (p=0.001) was high (59% of variance).

Conclusion:

Depression, hopelessness, and sleep quality appeared to have a statistically significant relationship with desire for hastened death. Health care professionals finding desire for death in advanced cancer patients should not only consider depression and hopelessness, but also other factors such as poor sleep quality in their diagnostic formulations in order to provide the appropriate treatment.
From Hygiene to Public Health Education
Authors: Marcondes Ruth Sandoval , Candeias Nelly Martins Ferreira
Published: August 2007

This article is a review of the development of health education in Brazil (identified as “hygiene” in early times, it has evolved to “public health education”). The field has passed through infancy and adolescence facing all kinds of problems and is entering adulthood with health education leadership now in the hands of an increasing number of specialists trained in the country. The authors suggest that to hasten progress, more attention should be given to integration of health education to health programs, to stimulation of research, to preparation of health personnel, and to administrative support of health education services.
Phenomenology and Outcome of Factitious Disorders in Otolaryngology Clinic in Oman
Authors: Bhargava Deepa , Al-Abri Rashid , Rizvi Syed Gauher A. , Al Okbi Mohammed H. , Bhargava Kamlesh , Al-Adawi Samir
Published: August 2007

The phenomenology of factitious disorders from the Arab part of the world has been lacking in the medical literature and few reports have emerged from otolaryngology. Using an observational prospective case series study ( n =19) with long-term follow-up (two to six years), the present study reports the magnitude and mode of clinical profile of factitious disorders in a tertiary care hospital in Oman, an Arab-Islamic country. The outcome was operationalized as prognosis following culturally sensitive intervention akin to confrontation technique. The present observation suggests the prevalence of factitious disorders in the otolaryngology tertiary care setting was 0.2%. Approximately 42.1% ( n = 8) had hemorrhagic factitious disorders, 15.8% ( n = 3) were those who feigned for multiple surgical interventions. Approximately 15.8% ( n = 3) presented neurological factitious disorders while the remaining 26.3% ( n = 5) clinical profile suggested minor feigned illnesses. Objective “evidence factitia” was present in 68.4% ( n = 13) of the cases. On subsequent follow-up, nine patients with chronic forms became asymptomatic, three patients had fewer episodes, four patients were unchanged, and three patients were lost to follow-up. The prognosis was good in patients who did not have associated psychiatric illnesses as compared to those with psychiatric disorders. Factitious disorders are often incorrectly diagnosed, with all consequences in terms of adverse sequels. The observed good prognostic outcomes are discussed in the context of socio-cultural patterning and the factors that may shape the presentation of factitious disorders in Oman.
Developing Students' Metacognitive Awareness in Asynchronous Learning Networks in Comparison to Face-to-Face Discussion Groups
Authors: Michalsky Tova , Zion Michal , Mevarech Zemira R.
Published: August 2007

The main goal of the present study is to investigate empirically the effects of Asynchronic Learning Network (ALN) embedded within metacognitive instruction (META) on two components of metacognitive awareness: Knowledge about Cognition (KC) and Regulation of Cognition (RC). Participants were 202 tenth grade students: 102 students who studied under the ALN+META instructional method, and 100 students who studied under Face-to-Face interaction (F2F) embedded within META. Results indicated that ALN+META students significantly outperformed their F2F+META counterparts on both KC and RC. These results were strengthened by a qualitative analysis of RC under the different instructional methods. The improvement of RC behavior in the ALN+META written discourse clearly indicates the crucial effects of RC on the progress and success of the inquiry processes. ALN+META is a promising learning environment, carrying a great potential for enhancing metacognitive awareness among students.
Being the Same Isn't Enough: Impact of Male and Female Mentors on Computer Self-Efficacy of College Students in It-Related Fields
Authors: Goh Debbie , Ogan Christine , Ahuja Manju , Herring Susan C. , Robinson Jean C.
Published: August 2007

This study investigates the relationship between computer self-efficacy, mentoring, and the gender of mentors and students. The decline of women in IT-related programs of U.S. universities has led scholars to suggest that making more female faculty mentors available could raise female students' computer self-efficacy. This could address women's computational reticence and encourage more women to enter and remain in the programs. A survey of students from IT-related programs in five U.S. universities shows that extent of mentoring received, gender of students, and time students spent on computers as teenagers were significant predictors of computer self-efficacy. Extent of mentoring, gender of students, and gender of mentors have significant main effects on computer self-efficacy. Students with male mentors reported significantly higher computer self-efficacy while students with female mentors reported lower computer self-efficacy. Female students with no mentors reported the lowest level of computer self-efficacy.
Specific Psychiatric Morbidity among a Sample of Asthmatics in South Western Nigeria
Authors: Mosaku Samuel K. , Erhabor Gregory E. , Morakinyo Olufemi
Published: August 2007

Objective:

This study was to identify specific psychiatric morbidity among asthma patients and to compare their rates to controls.

Method:

Hundred consecutive asthmatics were screened using the General Health Questionnaire (GHQ-30), and the Present State Examination (PSE). The same instruments were also administered to 75 healthy individuals, and 75 orthopaedic patients.

Results:

Patients with asthma had a higher occurrence of psychopathology. The specific psychiatric diagnoses among asthmatics were generalized anxiety disorder (23%), depressive disorder (11%), while 2% had panic disorder.

Conclusion:

Psychiatric morbidity is more common among asthmatics, than the general population and other patient group.
A Community Approach to the Prevention of Alcohol-Related Problems: The San Francisco Experience
Authors: Wallack Lawrence
Published: August 2007

This article describes the San Francisco Prevention Project, a community level intervention designed to prevent alcohol-related problems. The intervention is based on a systems perspective and merges academic and practical perspectives at the community level. The project uses a three component approach of research, community education, and planning for action. Each component is described and a summary of the first year experience is provided.
The Impact of Preservice Teachers' Emotions on Computer Use: A Formative Analysis
Authors: Kay Robin
Published: August 2007

Previous research on the effect of technology-based preservice education programs has been assessed by examining changes in computer ability and attitudes. Systematic exploration looking at the effect of these programs on computer use has been noticeably absent. In addition, the role of emotions and use of computers has been largely ignored with one exception, computer anxiety. The purpose of the following study was to examine the impact of four basic emotions (anger, anxiety, happiness, sadness) on use of computers by preservice teachers in their coursework (university use) and in their practice teaching (field use). Happiness was reported often while learning new software—anxiety, anger, and sadness were experienced sometimes. All four emotion constructs were significantly correlated with all four university use constructs at the beginning of the laptop program. Increased positive emotions (happiness) were significantly correlated with increased use of computers at the university by the end of the program. Finally, increases in positive emotions and decreases in negative emotions were significantly related to teacher and student-based use of computers in the field.