bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of Music Therapy on Dental Anxiety in Periodontal Surgery
Authors: ÖZCAN Muhammed Furkan , HENDEK Meltem , BARIŞ Kubilay , OLGUN Ebru
Published: February 2024

Effect of Music Therapy on Dental Anxiety in Periodontal Surgery
Introduction: Pharmacological or non-pharmacological methods are applied to eliminate fear and anxiety problems related to dental treatments in many patients. As a non-invasive, non-pharmacological method with an anxiolytic effect, music therapy is preferred in the management of anxiety and fear. This study aimed to investigate the effect of music therapy on dental anxiety in patients scheduled to undergo periodontal surgery.
Material and Method: The study included a total of 46 patients, 23 in the study group and 23 in the control group, who were scheduled to undergo periodontal surgery. During the surgical procedure, the patients in the study group listened to music using in-ear headphones that isolated ambient sounds. The patients in the control group wore in-ear headphones to isolate ambient sounds, but they did not listen to any music. All patients were asked to complete the Modified Dentistry Anxiety Scale (MDAS), the State-Trait Anxiety Inventory-State (STAI-S), and the Dental Fear Survey (DFS) before and after surgery. Systolic blood pressure (SBP) and diastolic blood pressure were measured as vital signs before and after surgery, and the Visual Analog Scale (VAS) scores were recorded twice (at the end of and 30 minutes after the surgical procedure).
Results: In the study group, the post-test MDAS, STAI-S, and DFS measurement values showed statistically significant decreases compared to the pre-test measurement values (P<0.001, P=0.009, and P<0.001, respectively), but there was no statistically significant difference in the control group (P=0.093, P=0.923, and P=0.460, respectively). In both the study and control groups, the post-test VAS measurement values statistically significantly decreased compared to the pre-test measurement values (P=0.002 and P=0.019, respectively). While the post-test SBP values decreased statistically significantly in the study group compared to the pre-test measurement values (P=0.020), there was no statistically significant difference in the control group (P=0.705). No statistically significant difference was found between the pre-test and post-test measurement values of the DFS scores in the study or control group (P=0.083 and P=0.160, respectively).
Clinical significance: This study is the first clinical study to evaluate the effect of music on anxiety in periodontal surgery simultaneously with four different scales. Music therapy was found to be effective in reducing dental anxiety and fear during periodontal surgery.
Guillaume Devin : une démarche de sciences sociales de l’international
Authors: Dudouet François-Xavier , Petiteville Franck , Vion Antoine , wihtol de Wenden Catherine
Published: February 2024

Les relations internationales sont un objet sociologique comme les autres. À la différence des pères fondateurs de la discipline outre-Manche et outre-Atlantique, très attachés à une ligne de séparation entre les affaires du dedans (recherche de la vie bonne) et les affaires du dehors (recherche de la survie), Guillaume Devin n’entend pas embrasser une lecture théorique figée de la réalité internationale, mais à ouvrir les manières de la saisir et ce, en mobilisant une pluralité de références sociologiques, mais aussi au-delà. L’objet de cet article sera de mettre en relief les singularités de ce geste scientifique en prenant en considération l’ensemble des disciplines connexes qui lui ont servi en partie de matrices (droit, histoire) et en insistant sur quelques prolongements et enseignements méthodologiques de ce geste.
Le multilatéralisme en mouvements
Authors: Guilbaud Auriane , Larhant Morgan , Leloup Mathilde , Tanke Sarah , Tordjman Simon
Published: February 2024

Les organisations internationales s’imposent depuis 1945 comme des arènes incontournables des politiques étrangères. Pour autant, en dépit d’une intensification de l’activité éditoriale dans l’immédiat post-guerre froide, le multilatéralisme ne constitue au début des années 2000 qu’un domaine résiduel des études internationales francophones. Aborder les organisations internationales comme une « forme majeure de l’action internationale » et s’attacher à en accroître l’intelligibilité supposent de rompre avec une lecture de l’international encore dominée par le jeu de la puissance et la volonté de domination. Cette entreprise intellectuelle – qui prit rapidement des dimensions collectives (co-écriture et co-direction d’ouvrages, directions de mémoires de Master et de thèses de doctorats, création et animation du Groupe de Recherche sur l’Action Multilatérale [gram]) – est également une réhabilitation de la solidarité et de la coopération comme clés de lecture du jeu politique international. Plutôt que la permanence, il s’agit, chez Guillaume Devin, de privilégier l’étude des marges de manoeuvre, des jeux d’acteurs, et du changement de ces institutions en même temps que d’instaurer une lecture large de leur fonctionnalité.
Les structures sociales des organisations internationales : la production de l’équivoque
Authors: Amicelle Anthony , Crespy Cécile , Tordjman Simon
Published: February 2024

Dès la seconde moitié du vingtième siècle, l’expansion des organisations internationales(oi) s’accompagne d’appels à en résorber la complexité pour en accroître la lisibilité et l’efficacité. Régulièrement rappelée par les États-membres et les fonctionnaires internationaux, la réduction des doublons et des concurrences intra et inter-organisationnels constituerait une condition indispensable à la revitalisation du multilatéralisme et un objectif consensuel des réformes qui le travaillent. Considérant ces imbrications au-delà de leurs seules dimensions institutionnelles, et en s’appuyant sur trois cas d’études (Groupe d’Action Financière [gafi],ocde, Nations unies), l’article propose un renversement de perspective en saisissant les articulations entre différents espaces sociaux et registres d’action comme un élément structurant de production du multilatéralisme. Loin d’éroder leur pouvoir normatif, ces relations et les arrangements auxquels elles donnent lieu au sein de nombreusesoileur fournissent en retour des ressources importantes pour affirmer leur propre autorité et légitimité.
Stratégies d’accès aux écoles secondaires par des parents dans le marché scolaire montréalais : entre reproduction et mobilité sociale
Authors: Grenier Véronique , Castonguay-Payant Justine
Published: February 2024

Cet article examine les stratégies mobilisées lors du choix de l’école secondaire par des parents dans le marché scolaire montréalais. Mobilisant une sociologie compréhensive et un cadre d’analyse articulant les facteurs microsociologiques et macrosociologiques, il se penche sur l’orchestration des stratégies d’accès, telle que réalisée par des parents, et à partir de quels ancrages celle-ci est élaborée. S’appuyant sur cinquante-sept entretiens semi-dirigés, l’article illustre la mobilisation de différentes ressources et stratégies afin d’atténuer les limites et contraintes établies par le marché scolaire montréalais. Les parents dotés de capitaux culturels, économiques et sociaux ont une certaine aisance à mobiliser les structures à leur avantage, à déjouer les contraintes, à comprendre le marché scolaire montréalais et à se l’approprier, soulevant un enjeu relatif à l’équité devant les options. Quelques parents moins dotés en capitaux établissent aussi des stratégies d’accès, indiquant de possibles phénomènes de mobilité sociale ascendante à travers le choix.
Manager de rayon en intégré ou en indépendant ?
Authors: Racine Florent
Published: February 2024

Afin de comprendre la dynamique du groupe des managers de rayon des grandes
surfaces alimentaires, cet article propose de comparer l’évolution des conditions de travail
et d’emploi sur ses deux principaux segments professionnels et de saisir la relation qui en
découle. Ces managers travaillent en effet soit dans une enseigne dite « intégrée », soit
dans une enseigne dite « indépendante », structure juridique qui a une influence
déterminante sur leurs conditions de travail et d’emploi. C’est particulièrement le cas
depuis le tournant des années 2010 où les difficultés économiques croissantes des enseignes
intégrées les poussent à réorganiser les rayons et le poste de manager. Chez les
indépendants — qui phagocytent les parts de marchés de leurs concurrents —, la situation est
tout autre et le poste de manager n’a que peu évolué depuis les années 2000. Ce qui
interroge inévitablement sur l’évolution des relations entre les segments.
Maisons de soins palliatifs au Québec et aide médicale à mourir : liaisons dangereuses ?
Authors: de Gabory Thomas , Caenepeel Didier
Published: February 2024

La pratique de l’aide médicale à mourir au sein des services de soins palliatifs, et plus précisément dans les maisons de soins palliatifs au Québec, remet en question leur raison d’être. Cet article, s’appuyant sur la méthode d’analyse en éthique clinique, a pour objectifs, d’une part, d’analyser ce qu’est la raison d’être des soins palliatifs et des maisons de soins palliatifs telles qu’elles existent au Québec et, d’autre part, de mettre en perspective cette raison d’être avec l’aide médicale à mourir introduite récemment dans ces milieux. Cet article dégage les effets possiblement délétères de l’offre de l’aide médicale à mourir sur la raison d’être des soins palliatifs et plus particulièrement des maisons de soins palliatifs. Ces effets sont d’ordre temporel (la temporalité de l’apprivoisement du mourir), relationnel (les relations soignants-patient-proches) et communautaire (les communautés qui se forment avec et autour des patients).
Psychoacoustic Foundations of Major-Minor Tonality
Authors: Parncutt Richard
Published: February 2024

A fascinating interdisciplinary approach to how everyday Western music works, and why the tones, melodies, and chords combine as they do.

Despite the cultural diversity of our globalized world, most Western music is still structured around major and minor scales and chords. Countless thinkers and scientists of the past have struggled to explain the nature and origin of musical structures. In Psychoacoustic Foundations of Major-Minor Tonality, music psychologist Richard Parncutt offers a fresh take, combining music theory—Rameau's fundamental bass, Riemann's harmonic function, Schenker's hierarchic analysis, Forte's pitch-class set theory—with psychology—Bregman's auditory scene, Terhardt's virtual pitch, Krumhansl's tonal hierarchy. Drawing on statistical analyses of notated music corpora, Parncutt charts a middle path between cultural relativism and scientific positivism to bring music theory into meaningful discourse with empirical research.

Our musical subjectivity, Parncutt explains, depends on our past musical experience and hence on music history and its social contexts. It also depends on physical sound properties, as investigated in psychoacoustics with auditory experiments and mathematical models. Parncutt's evidence-based theory of major-minor tonality draws on his interdisciplinary background to present a theory that is comprehensive, creative, and critical. Examining concepts of interval, consonance, chord root, leading tone, harmonic progression, and modulation, he asks:

• Why are some scale tones and chord progressions more common than others?

• What aspects of major-minor tonality are based on human biology or general perceptual principles? What aspects are culturally arbitrary? And what about colonial history?

Original and provocative, Psychoacoustic Foundations of Major-Minor Tonality promises to become a foundational text in both music theory and music cognition.
ScRNA-seq of Diverse Pheochromocytoma Patients Reveals Distinct Microenvironment Characteristics and Supports an Informative Molecular Classification System
Authors: Qin Sen , Xu Yawei , Yu Shimiao , Han Wencong , Fan Shiheng , Ai Wenxiang , Zhang Kenan , Wang Yizhou , Zhou Xuehong , Shen Qi , Gong Kan , Sun Luyang , Zhang Zheng
Published: February 2024

Pheochromocytomas (PCCs) are rare neuroendocrine tumors that originate from chromaffin cells in the adrenal gland. However, the cellular molecular characteristics and immune microenvironment of PCCs are incompletely understood. Here, we performed single-cell RNA sequencing (scRNA-seq) on 16 tissues from 4 sporadic unclassified PCC patients and 1 hereditary PCC patient with Von Hippel-Lindau (VHL) syndrome. We found that intra-tumoral heterogeneity was less extensive than the inter-individual heterogeneity of PCCs. Further, the unclassified PCC patients were divided into two types, metabolism-type (marked by NDUFA4L2 and COX4I2) and kinase-type (marked by RET and PNMT), validated by immunohistochemical staining. Trajectory analysis of tumor evolution revealed that metabolism-type PCC cells display phenotype of consistently active metabolism and increased metastasis potential, while kinase-type PCC cells showed decreased epinephrine synthesis and neuron-like phenotypes. Cell-cell communication analysis showed activation of the annexin pathway and a strong inflammation reaction in metabolism-type PCCs and activation of FGF signaling in the kinase-type PCC. Although multispectral immunofluorescence staining showed a lack of CD8 + T cell infiltration in both metabolism-type and kinase-type PCCs, only the kinase-type PCC exhibited downregulation of HLA-I molecules that possibly regulated by RET , suggesting the potential of combined therapy with kinase inhibitors and immunotherapy for kinase-type PCCs; in contrast, the application of immunotherapy to metabolism-type PCCs (with antigen presentation ability) is likely unsuitable. Our study presents a single-cell transcriptomics-based molecular classification and microenvironment characterization of PCCs, providing clues for potential therapeutic strategies to treat PCCs.
Dynamic simulations of feeding and respiration of the early Cambrian periderm-bearing cnidarian polyps
Authors: Zhang Yiheng , Wang Xing , Han Jian , Xiao Juyue , Yong Yuanyuan , Yu Chiyang , Yue Ning , Sun Jie , He Kaiyue , Hao Wenjing , Zhang Tao , Wang Bin , Wang Deng , Yang Xiaoguang
Published: February 2024

Although fossil evidence suggests the existence of an early muscular system in the ancient cnidarian jellyfish from the early Cambrian Kuanchuanpu biota (
ca
. 535 Ma), south China, the mechanisms underlying the feeding and respiration of the early jellyfish are conjectural. Recently, the polyp inside the periderm of olivooids was demonstrated to be a calyx-like structure, most likely bearing short tentacles and bundles of coronal muscles at the edge of the calyx, thus presumably contributing to feeding and respiration. Here, we simulate the contraction and expansion of the microscopic periderm-bearing olivooid
Quadrapyrgites
via the fluid-structure interaction computational fluid dynamics (CFD) method to investigate their feeding and respiratory activities. The simulations show that the rate of water inhalation by the polyp subumbrella is positively correlated with the rate of contraction and expansion of the coronal muscles, consistent with the previous feeding and respiration hypothesis. The dynamic simulations also show that the frequent inhalation/exhalation of water through the periderm polyp expansion/contraction conducted by the muscular system of
Quadrapyrgites
most likely represents the ancestral feeding and respiration patterns of Cambrian sedentary medusozoans that predated the rhythmic jet-propelled swimming of the modern jellyfish. Most importantly for these Cambrian microscopic sedentary medusozoans, the increase of body size and stronger capacity of muscle contraction may have been indispensable in the stepwise evolution of active feeding and subsequent swimming in a higher flow (or higher Reynolds number) environment.To the best of our knowledge, our study is the first to simulate the feeding and respiration patterns of Quadrapyrgites by introducing a dynamic fluid-structure coupling method, revealing the relationship between the ancient medusozoans and modern jellyfish.
Overnight fasting facilitates safety learning by changing the neurophysiological response to relief from threat omission
Authors: Papalini Silvia , Beckers Tom , Van Oudenhove Lukas , Vervliet Bram
Published: February 2024

Excessive avoidance and slow extinction of fear are hallmarks of anxiety disorders. We have previously found that overnight fasting diminishes excessive avoidance and speeds up fear extinction by decreasing subjective relief during threat omissions. Since relief tracks the reward prediction error signal that governs safety learning, we hypothesized that these effects of fasting might be linked to a decreased activation in brain regions related to reward prediction error processing. Hence, we replicated our previous study in a 3T-MRI scanner. Overnight fasting increased effective avoidance and sped up fear extinction learning. During extinction, the fasting group showed lower activations in the ventromedial prefrontal cortex and nucleus accumbens in response to threat omissions signaled by a safe cue. Nucleus accumbens activations were modulated by relief in the control group. This study provides support for overnight fasting as an adjunct to treatments for anxiety, but the effects should be investigated in anxious patients.
Allosteric modulation of the CXCR4:CXCL12 axis by targeting receptor nanoclustering via the TMV-TMVI domain
Authors: García-Cuesta Eva M , Martínez Pablo , Selvaraju Karthik , Ulltjärn Gabriel , Gómez Pozo Adrián Miguel , D'Agostino Gianluca , Gardeta Sofia , Quijada-Freire Adriana , Blanco Gabella Patricia , Roca Carlos , Hoyo Daniel del , Jiménez-Saiz Rodrigo , García-Rubia Alfonso , Soler Palacios Blanca , Lucas Pilar , Ayala-Bueno Rosa , Santander Acerete Noelia , Carrasco Yolanda , Oscar Sorzano Carlos , Martinez Ana , Campillo Nuria E , Jensen Lasse D , Rodriguez Frade Jose Miguel , Santiago César , Mellado Mario
Published: February 2024

CXCR4 is a ubiquitously expressed chemokine receptor that regulates leukocyte trafficking and arrest in both homeostatic and pathological states. It also participates in organogenesis, HIV-1 infection, and tumor development. Despite the potential therapeutic benefit of CXCR4 antagonists, only one, plerixafor (AMD3100), which blocks the ligand-binding site, has reached the clinic. Recent advances in imaging and biophysical techniques have provided a richer understanding of the membrane organization and dynamics of this receptor. Activation of CXCR4 by CXCL12 reduces the number of CXCR4 monomers/dimers at the cell membrane and increases the formation of large nanoclusters, which are largely immobile and are required for correct cell orientation to chemoattractant gradients. Mechanistically, CXCR4 activation involves a structural motif defined by residues in TMV and TMVI. Using this structural motif as a template, we performed in silico molecular modeling followed by in vitro screening of a small compound library to identify negative allosteric modulators of CXCR4 that do not affect CXCL12 binding. We identified AGR1.137, a small molecule that abolishes CXCL12-mediated receptor nanoclustering and dynamics and blocks the ability of cells to sense CXCL12 gradients both in vitro and in vivo while preserving ligand binding and receptor internalization.
Knockdown of PHOX2B in the retrotrapezoid nucleus reduces the central CO2 chemoreflex in rats
Authors: Cardani Silvia , Janes Tara A. , Betzner William , Pagliardini Silvia
Published: February 2024

PHOX2B is a transcription factor essential for the development of the autonomic nervous system. Heterozygous mutations in the PHOX2B coding region are responsible for the occurrence of Congenital Central Hypoventilation Syndrome (CCHS), a rare neurological disorder characterised by inadequate chemosensitivity and life-threatening sleep-related hypoventilation. Animal studies suggest that chemoreflex defects are caused in part by the improper development or function of PHOX2B expressing neurons in the retrotrapezoid nucleus (RTN), a central hub for CO
2
chemosensitivity.Although the function of PHOX2B in rodents during development is well established, its role in the adult respiratory network remains unknown. In this study, we investigated whether reduction in PHOX2B expression in chemosensitive neuromedin-B (NMB) expressing neurons in the RTN altered respiratory function. Four weeks following local RTN injection of a lentiviral vector expressing the short hairpin RNA (shRNA) targeting
Phox2b
mRNA, a reduction of PHOX2B expression was observed in
Nmb
neurons compared to both naïve rats and rats injected with the non-target shRNA. PHOX2B knockdown did not affect breathing in room air or under hypoxia, but ventilation was significantly impaired during hypercapnia. PHOX2B knockdown did not alter
Nmb
expression but reduced the expression of both
Task2
and
Gpr4
, two CO
2
sensors in the RTN. We conclude that PHOX2B in the adult brain has an important role in CO
2
chemoreception and reduced PHOX2B expression in CCHS beyond the developmental period may contribute to the impaired central chemoreflex function.
سفری به یک رهسپار سرد
Authors: مهاجر سولماز , اونه ویبکه , پانیری جولیانا , اودونه داویده , آب نیکی محمد , همتی نژاد فرشته
Published: February 2024

تمرکز: تراوش های سرد کجا هستند و درآنجا چه اتفاقی می افتد و دانشمندان چگونه آنها را مطالعه می کنند.

 

اهداف یادگیری: پس از این درس، دانش آموزان باید بتوانند:

۱. با مشاهده و توصیف نقشه های علمی مجموعه داده های مختلف را به هم مرتبط کنند.

۲. بین دی اکسید کربن و گاز متان تفاوت قائل شوند.

۳. باورهای غلط در مورد گازهای گلخانه ای تصریح کنند.

۴. توضیح دهند که تراوش سرد چیست و چرا بیشتر هیدرات های گاز متان در حاشیه قاره رخ می دهد.

۵. برخی از روش هایی را که دانشمندان برای مکان یابی و مطالعه هیدرات های  گاز متان استفاده می کنند، شرح دهید.

 

پیش نیازها :قبل از این درس، دانش آموزان باید با درک نقشه ها، ساختار مولکولی و پیوند، و اثر گلخانه ای و گازها آشنا شوند.

 

کلید واژه ها: اقیانوس منجمد شمالی، متان، دی اکسید کربن، هیدرات گاز، تراوش سرد، گازهای گلخانه ای.
مجسمه سازی درشت، نیمه بزرگ و ریز زیاگان
Authors: ماریچ فیلیپ , پوتو مارگریتا پائولا , زیمرمن هایکه جین , پانیری جولیانا , آب نیکی محمد , همتی نژاد فرشته
Published: February 2024

تمرکز

درک از تنوع زیستی اقیانوس منجمد شمالی و کف اقیانوس، با تمرکز ویژه بر گونه های کمتر شناخته شده. چه نوع درشت، نیمه بزرگ و ریز زیاگان (گونه هایی) در کف اقیانوس زندگی می کنند و چه شکلی هستند؟

 

اهداف آموزشی

در این فعالیت، دانش‌آموزان (یک، دو یا چند) گونه‌هایی را که در یا نزدیک به کف اقیانوس منجمد شمالی زندگی می‌کنند شناسایی می‌کنند و با استفاده از خاک رس مدل‌سازی می‌کنند. از طریق این فعالیت، دانش آموزان امیدوارند که تفاوت های درشت، نیمه بزرگ و ریز زیاگان اقیانوس منجمد شمالی را درک کنند.

 

کلمات کلیدی

تنوع زیستی اقیانوس منجمد شمالی، گونه ها، جانوران.
Treatment of wastewater containing Pb and Fe using ion‐exchange techniques
Authors: Srinivasa Rao K , Dash PK , Sarangi D , Roy Chaudhury G , Misra VN
Published: March 2005

Treatment of wastewater containing lead and iron was examined using two different ion‐exchange resins namely Duolite ES 467 (containing amino‐phosphonic functional groups) and a chelating ion‐exchange resin (containing hydroxamic acid functional groups). Initially different sorption parameters such as contact time, pH, concentrations of sorbent, sorbate and chloride ion were studied. The sorption kinetics was observed to be fast and equilibrium could be reached within 30 min. Lead sorption efficiency increased with increase in pH whereas the opposite trend was observed with iron. The presence of chloride ions greatly reduced the Pb sorption efficiency in the case of Duolite ES 467. Column studies were carried out to recover Pb and Fe individually using Duolite ES 467 resin. The maximum uptake of Pb at pH 2 and 3 was observed to be 11.63 and 33.96 g dm−3 of resin respectively. Similarly, for Fe at pH 2 and 3 the uptake was observed to be 10.07 and 6.96 g dm−3 of resin respectively. In the presence of chloride ions, column studies were carried out using Duolite ES 467 for iron and chelating ion‐exchange resin containing hydroxamic acid functional groups for lead sorption. Hydroxamic acid resin's loading capacity remains constant for at least up to 20 cycles. Copyright © 2005 Society of Chemical Industry
Effects of intra‐peritoneal injection with NH4Cl, urea, or NH4Cl+urea on nitrogen excretion and metabolism in the African lungfish Protopterus dolloi
Authors: Ip Yuen K. , Peh Bee K. , Tam Wai L. , Wong Wai P. , Chew Shit F.
Published: March 2005

This study aimed to (1) determine if ammonia (as NH4Cl) injected intra‐peritoneally into the ureogenic slender African lungfish, Protopterus dolloi, was excreted directly rather than being converted to urea; (2) examine if injected urea was retained in this lungfish, leading to decreases in liver arginine and brain tryptophan levels, as observed during aestivation on land; and (3) elucidate if increase in internal ammonia level would affect urea excretion, when ammonia and urea are injected simultaneously into the fish. Despite being ureogenic, P. dolloi rapidly excreted the excess ammonia as ammonia within the subsequent 12 h after NH4Cl was injected into its peritoneal cavity. Injected ammonia was not detoxified into urea through the ornithine‐urea cycle, probably because it is energetically intensive to synthesize urea and because food was withheld before and during the experiment. In addition, injected ammonia was likely to stay in extracellular compartments available for direct excretion. At hour 24, only a small amount of ammonia accumulated in the muscle of these fish. In contrast, when urea was injected intra‐peritoneally into P. dolloi, only a small percentage (34%) of it was excreted during the subsequent 24–h period. A significant increase in the rate of urea excretion was observed only after 16 h. At hour 24, significant quantities of urea were retained in various tissues of P. dolloi. Injection with urea led to an apparent reduction in endogenous ammonia production, a significant decrease in the hepatic arginine content, and a significantly lower level of brain tryptophan in this lungfish. All three phenomena had been observed previously in aestivating P. dolloi. Hence, it is logical to deduce that urea synthesis and accumulation could be one of the essential factors in initiating and perpetuating aestivation in this lungfish. Through the injection of NH4Cl + urea, it was demonstrated that an increase in urea excretion occurred in P. dolloi within the first 12 h post‐injection, which was much earlier than that of fish injected with urea alone. These results suggest that urea excretion in P. dolloi is likely to be regulated by the level of internal ammonia in its body. J. Exp. Zool. 303A:272–282, 2005. © 2005 Wiley‐Liss, Inc.
K+‐Phosphatase activity of gill (Na+, K+)‐ATPase from the blue crab, Callinectes danae: Low‐salinity acclimation and expression of the α‐subunit
Authors: Masui D.C. , Furriel R.P.M. , Mantelatto F.L.M. , Mcnamara J.C. , Leone F.A.
Published: March 2005

The kinetic properties of a microsomal gill (Na+, K+) ATPase from the blue crab, Callinectes danae, acclimated to 15 ‰ salinity for 10 days, were analyzed using the substrate p‐nitrophenylphosphate. The (Na+, K+)‐ATPase hydrolyzed the substrate obeying Michaelian kinetics at a rate of V=102.9±4.3 U.mg−1 with K0.5=1.7±0.1 mmol.L−1, while stimulation by magnesium (V=93.7±2.3 U.mg−1; K0.5=1.40±0.03 mmol.L−1) and potassium ions (V=94.9±3.5 U.mg−1; K0.5=2.9±0.1 mmol.L−1) was cooperative. K+‐phosphatase activity was also stimulated by ammonium ions to a rate of V=106.2±2.2 U. mg−1 with K0.5=9.8±0.2 mmol.L−1, following cooperative kinetics (nH=2.9). However, K+‐phosphatase activity was not stimulated further by K+ plus NH4+ ions. Sodium ions (KI=22.7±1.7 mmol.L−1), and orthovanadate (KI=28.1±1.4 nmol.L−1) completely inhibited PNPPase activity while ouabain inhibition reached almost 75% (KI=142.0±7.1 μmol.L‐1). Western blotting analysis revealed increased expression of the (Na+, K+)‐ATPase α‐subunit in crabs acclimated to 15‰ salinity compared to those acclimated to 33‰ salinity. The increase in (Na+, K+)‐ATPase activity in C. danae gill tissue in response to low‐salinity acclimation apparently derives from the increased expression of the (Na+, K)‐ATPase α‐subunit; phosphate‐hydrolyzing enzymes other than (Na+, K+)‐ATPase are also expressed. These findings allow a better understanding of the kinetic behavior of the enzymes that underlie the osmoregulatory mechanisms of euryhaline crustaceans. J. Exp. Zool. 303A:294–307, 2005. © 2005 Wiley‐Liss, Inc.
An increase of uricogenesis in the Kuruma shrimp Marsupenaeus japonicus under nitrite stress
Authors: Cheng Sha‐Yen , Lee Won‐Chung , Chen Jiann‐Chu
Published: March 2005

Kuruma shrimp Marsupenaeus japonicus Bate, under the stress of 0.36 and 1.39 mM nitrite at 30 ‰ (parts per thousand, g kg−1) for 48 h, were examined for nucleotide‐related compounds, specific activities of xanthine dehydrogenase (XDH), xanthine oxidase (XOD), and uricase. The levels of total nucleotide‐related compounds, including xanthine and hypoxanthine, in the gill increased directly with ambient nitrite, whereas the levels of total nucleotide‐related compounds, including xanthine and hypoxanthine, in the hepatopancreas were inversely related to ambient nitrite. Specific activity of XOD in the hepatopancreas increased directly with ambient nitrite, whereas no significant difference in uricase activity in the hepatopancreas was observed among three treatments. In another experiment, M. japonicus, following 48 h exposure to 0.36 and 1.39 mM nitrite, were examined for ammonia, urea, and urate levels in tissues. Hemolymph urea and exoskeleton urate levels increased directly with ambient nitrite, whereas hemolymph urate and exoskeleton urea levels were inversely related to ambient nitrite. It is concluded that M. japonicus exhibited uricogenesis and uricolysis, and an increase of uricogenesis occurred for the shrimp under nitrite stress. Urate produced in the hepatopancreas was transported and accumulated in the epidermis, and removed along with the exoskeleton at the time of molting. J. Exp. Zool. 303A:308–318, 2005. © 2005 Wiley‐Liss, Inc.
Static SIMS studies of fatty alcohols, amines and esters on gold and aluminium–magnesium alloy surfaces
Authors: Miller D. J. , Sun L. , Walzak M. J. , McIntyre N. S. , Chvedov D. , Rosenfeld A.
Published: March 2005

Static secondary ion mass spectrometry was used to study the chemical reactions and lateral distributions of fatty amines, alcohols and esters spin coated onto gold surfaces and commercial aluminium–magnesium (Al–Mg) alloy surfaces, cleaned using UV–ozone. The aim of this study is to develop an understanding of the interactions of model lubricants with metal surfaces, such as gold and aluminium. This static SIMS study of organic thin films has been able to identify specific reaction products on the aluminium surface for each functional group. This work demonstrates that organic molecules with alcohol, ester and amine functional groups undergo specific chemical reactions with oxidized Al–Mg alloy surfaces. For example, films composed of the fatty alcohol dodecanol were observed to emit monomers, dimers and trimers with discrete distributions. In addition, negative secondary ion mass spectra indicate that a surface carboxylate is formed from the alcohol. The formation of carboxylate reaction products was confirmed by Fourier transform infrared spectroscopy. On Al–Mg alloy surfaces, a direct interaction with the amine and aluminium oxide surface is observed by the detection of a molecular ion that corresponds to the mass of dodecylamine and AlO−, characteristic of aluminium oxide. Ethyl laurate was shown to eliminate the ethyl group, leaving the laurate anion. This study demonstrates the ability of time‐of‐flight (ToF) SIMS to discriminate and detect chemical reaction products formed between model lubricant molecules and metal surfaces. As a result of this study, the use of ToF‐SIMS to identify reaction products of model lubricants can be extended to provide a better understanding of the interactions of lubricants and metal surfaces at high temperatures and pressures that more closely resemble the conditions encountered in industrial rolling processes. Copyright © 2005 John Wiley & Sons, Ltd.
Vagal heart rate responses to chronic beta‐blockade in human heart failure relate to cardiac norepinephrine spillover
Authors: Kubo Toshihiko , Parker John D. , Azevedo Eduardo R. , Atchison Deborah J. , Newton Gary E. , Picton Peter , Floras John S.
Published: March 2005

We have documented a pre‐junctional β‐2 adrenoceptor mediated reduction in cardiac norepinephrine spillover (CNES) in heart failure patients receiving chronic β‐blockade. Our present objective was to ascertain the consequence of this decrease for vagal heart rate (HR) regulation by determining CNES, arterial baroreflex sensitivity for HR (BRS) and arterial baroreflex modulation of muscle sympathetic nerve activity (MSNA) before and upon 4 months of β‐blockade with either carvedilol or metoprolol. In 19 heart failure patients in sinus rhythm (age: 55±2 [mean±S.E.]; ejection fraction: 20±2%), β‐blockade increased BRS from 4.8±0.9 to 7.9±1.3 ms/mm Hg (P<0.005) but had no effect on arterial baroreflex modulation of MSNA. Changes in CNES and BRS were inversely related (r=–0.52; n=16, P<0.05). Chronic β‐blockade in heart failure augments reflex vagal control of HR at an efferent site of interaction involving blockade of cardiac sympathetic pre‐junctional β‐2 adrenoceptors that facilitate NE release.
China's Poor Regions: Rural–Urban Migration, Poverty, Economic Reform and Urbanization. By MEI ZHANG. [London and New York: RoutledgeCurzon, 2003. 205 pp. ISBN 0 415 32145-X]. On the Move: Women in Rural-to-Urban Migration in Contemporary China. Edited by ARIANNE M. GAETANO and TAMARA JACKA. [New York: Columbia University Press, 2004. 368 pp. Hard cover $69.50, £46.50, ISBN 0-231-12706-5; paperback $29.50, £20.00, ISBN 0 231-12707-3.]
Authors: Gao Mobo
Published: March 2005

China's Poor Region is based on the author's PhD thesis and has a foreword by Peter Nolan, the distinguished scholar at Cambridge. It is a questionnaire survey plus two-ended interviews of subjects in Shanxi province. It is important to point out that the subjects of the investigation are migrants internal to Shanxi and are mostly male workers at coal mines or construction sites. This is very different from the subjects of the second book reviewed, which deals only with women, but also involves migrants from across China.

After a survey of theories of rural poverty and rural to urban migration, Zhang goes on to describe the poverty in China and discusses the Chinese government policies to tackle rural poverty. In chapters three to five, Zhang describes the methodology and results of a case study of three sampled counties of 200 households. The final chapter is a very brief conclusion which suggests, among other points, that rural migration has played – and will continue to play – a positive role in social development and in resolving rural poverty.

Reading On the Move, the first question that came to my mind was: why women? What are the gender issues that make researching female migration as a separate study worthwhile? The informative introduction chapter not only discusses the aims and rationale of focusing on women, but also contains a brief survey of modern migration in China and brings together a whole range of gender issues to the subject. For example, “Outmigration may provide an important avenue of escape for women suffering gender oppression or violence,” such as the above average rate of suicide among rural women. Women suffer – or suffer more – from the patriarchal authority of parents or in-laws, and migration has an impact on that. One chapter in the book suggests that migrant women make more independent and informed decisions on who to marry and how to spend money. Even for those women who stay at home, having a migrant in the family changes the status of the women in the household as they take up new duties and responsibilities. There are other issues such as the emotional ties between mothers and children, and returned migrant women may also find themselves in a different emotional and social situation from that of the men.
A regional‐scale particle‐tracking method for nonstationary fractured media
Authors: Öhman Johan , Niemi Auli , Tsang Chin‐Fu
Published: March 2005

A regional‐scale transport model is introduced that is applicable to nonstationary and statistically inhomogeneous fractured media, provided that hydraulic flow, but not necessarily solute transport, can be approximated by equivalent continuum properties at some block scale. Upscaled flow and transport block properties are transferred from multiple fracture network realizations to a regional model with grid elements of size equal to that found valid for continuum approximation of flow. In the regional‐scale model, flow is solved in a stochastic continuum framework, whereas the transport calculations employ a random walk procedure. Block‐wise transit times are sampled from distributions linked to each block based on its underlying fracture network. To account for channeled transport larger than the block scale, several alternative sampling algorithms are introduced and compared. The most reasonable alternative incorporates a spatial persistence length in sampling the particle transit times; this tracer transport persistence length is related to interblock channeling, and is quantified by the number N of blocks. The approach is demonstrated for a set of field data, and the obtained regional‐scale particle breakthroughs are analyzed. These are fitted to the one‐dimensional advective‐dispersive equation to determine an effective macroscale dispersion coefficient for the regional scale. An interesting finding is that this macroscale dispersion coefficient is found to be a linear function of the transport persistence, N, with a slope equal to a representative mean block‐scale dispersion coefficient and a constant that incorporates background dispersion arising from the regional heterogeneous conductivity field.
Telomerase limits the extent of base pairing between template RNA and telomeric DNA
Authors: Förstemann Klaus , Lingner Joachim
Published: March 2005

Telomerase is the ribonucleoprotein reverse transcriptase that adds telomeric DNA repeats to the ends of chromosomes. This involves annealing of the telomerase RNA template to the 3′ end of the chromosome, reverse transcription of the RNA template by the telomerase reverse transcriptase polypeptide and translocation. Here, we overexpress and partially purify the catalytically active yeast telomerase core in its natural host and probe telomerase RNA base methylation accessibility with dimethyl sulphate in the presence and absence of a DNA substrate and after substrate elongation. The length of the RNA–DNA hybrid is kept constant at seven base pairs after primer binding and elongation. Thus, new base‐pair formation at the 3′ end of the substrate during elongation coincides with disruption of base‐pair interactions at the other side of the template. Presumably, this circumvents the generation of an exceedingly high energy barrier for translocation and dissociation. Our analysis also corroborates recently proposed yeast telomerase RNA secondary structure models.
Nucleosome binding and histone methyltransferase activity of Drosophila PRC2
Authors: Nekrasov Maxim , Wild Brigitte , Müller Jürg
Published: March 2005

The Drosophila Polycomb group protein E(z) is a histone methyltransferase (HMTase) that is essential for maintaining HOX gene silencing during development. E(z) exists in a multiprotein complex called Polycomb repressive complex 2 (PRC2) that also contains Su(z)12, Esc and Nurf55. Reconstituted recombinant PRC2 methylates nucleosomes in vitro, but recombinant E(z) on its own shows only poor HMTase activity on nucleosomes. Here, we investigate the function of the PRC2 subunits. We show that PRC2 binds to nucleosomes in vitro but that individual PRC2 subunits alone do not bind to nucleosomes. By analysing PRC2 subcomplexes, we show that Su(z)12–Nurf55 is the minimal nucleosome‐binding module of PRC2 and that Esc contributes to high‐affinity binding of PRC2 nucleosomes. We find that nucleosome binding of PRC2 is not sufficient for histone methylation and that only complexes that contain Esc protein show robust HMTase activity. These observations suggest that different subunits provide mechanistically distinct functions within the PRC2 HMTase: the nucleosome‐binding subunits Su(z)12 and Nurf55 anchor the E(z) enzyme on chromatin substrates, whereas Esc is needed to boost enzymatic activity.
Demonstration of an optical polarization magnifier with low birefringence
Authors: Lintz M. , Guéna J. , Bouchiat M.-A. , Chauvat D.
Published: March 2005

In any polarimetric measurement technique, enhancing the laser polarization change of a laser beam before it reaches the analyzer can help in improving the sensitivity. Enhancement of a small polarization rotation can be performed using an optical component having a large linear dichroism, the enhancement factor being equal to the square root of the ratio of the two transmission factors. A pile of parallel plates at Brewster incidence seems appropriate for realizing such a polarization magnifier. In this article, we address the problem raised by the interference in the plates and between the plates, which affects the measurement by giving rise to birefringence. We demonstrate that wedged plates provide a convenient and efficient way to avoid this interference. We have implemented and characterized devices with four and six wedged plates at Brewster incidence, which have led to a decisive improvement of the signal-to-noise ratio in our ongoing parity violation measurement.
Fabrication of InAs quantum dots in AlAs∕GaAs DBR pillar microcavities for single photon sources
Authors: Zhang Bingyang , Solomon Glenn S. , Pelton Matthew , Plant Jocelyn , Santori Charles , Vučković Jelena , Yamamoto Yoshihisa
Published: March 2005

We report the molecular beam epitaxy growth of low-density strain-induced InAs quantum dots (QD) embedded in an AlAs∕GaAs distributed Bragg reflector structure for a triggered photon source. By optimal selection of growth temperature, InAs deposited thickness and other experimental parameters, it is possible to grow low density (10∕μm2) InAs quantum dots with a suitable emission wavelength for a triggered photon source. The empirical formulas for the refractive indices of AlAs and GaAs materials at high temperature over a wide wavelength range are constructed by combining high resolution x-ray diffraction, dynamic optical reflectivity, and optical reflectivity spectrum techniques. Utilizing the electron-beam lithography and electron-cyclotron-resonance plasma etching techniques, a micropost microcavity with the top diameter of 0.6μm and the post height of 4.2μm has been fabricated. Narrow, spectrally limited single QD emission embedded in a micropost microcavity is observed in the photoluminescence.
Potential mapping of pentacene thin-film transistors using purely electric atomic-force-microscope potentiometry
Authors: Nakamura Masakazu , Goto Naoyuki , Ohashi Noboru , Sakai Masatoshi , Kudo Kazuhiro
Published: March 2005

Potential mapping of organic thin-film transistors (TFTs) has been carried out using originally developed atomic-force-microscope potentiometry (AFMP). The technique is suitable for the accurate measurement at metal–semiconductor boundaries of working TFTs. Potential drops near metal–organic boundaries are observed for both source and drain Au top contacts of a pentacene TFT. The approximate width of the steeper potential slope is 400 nm, which is larger than the spatial resolution of AFMP. The potential drop is considered to be due to a damaged area with low carrier mobility caused by the Au evaporation, which is also reproduced by device simulation.
An Intertemporal International Asset Pricing Model: Theory and Empirical Evidence
Authors: Chang Jow‐ran , Errunza Vihang , Hogan Ked , Hung Mao‐wei
Published: March 2005

We extend Campbell's (1993) model to develop an intertemporal international asset pricing model (IAPM). We show that the expected international asset return is determined by a weighted average of market risk, market hedging risk, exchange rate risk and exchange rate hedging risk. These weights sum up to one. Our model explicitly separates hedging against changes in the investment opportunity set from hedging against exchange rate changes as well as exchange rate risk from intertemporal hedging risk. A test of the conditional version of our intertemporal IAPM using a multivariate GARCH process supports the asset pricing model. We find that the exchange rate risk is important for pricing international equity returns and it is much more important than intertemporal hedging risk.
Diagnosis and procedure‐specific survival among transfusion of recipients in 1993 and 2000, Örebro County, Sweden
Authors: Tynell E. , Norda R. , Montgomery S. M. , Björkman A.
Published: March 2005

Background and objectives  Survival rates in patients transfused in 1993 and 2000 were compared in relation to diagnoses and surgical interventions.

Materials and methods  Blood centre and hospital records of all patients transfused from March to May in Örebro County in 1993 (n = 932) and 2000 (n = 990), were matched with the national register of deaths.

Results  Relative risk of death within 1 year, adjusted for diagnoses, operations and other confounders in patients transfused in 2000 compared to 1993 was 0·78 (CI 0·66–0·91). Among those transfused 1993, 39% were alive after 7 years.

Conclusion  The improved survival among those transfused in 2000 could not be accounted for by differences in ages or case‐mix.
Decentralizing Wage Bargaining in Germany — A Way to Increase Employment?
Authors: Ochel Wolfgang
Published: March 2005

Abstract.  The area‐wide wage agreement is at the centre of Germany's system of collective bargaining. In recent years, however, there has been a tendency towards the decentralization of collective bargaining. Individual wage agreements have led to more moderate wage developments, whilst collective agreements with individual firms, and agreements at the production unit level, have not had this moderating effect. On the other hand, collective bargaining has become more flexible, leading to greater pay differentiation. The further decentralization of collective bargaining, although desirable, has given rise to objections based in constitutional law and to resistance from employees and employers.
Comprehensive Education for the Unemployed — Evaluating the Effects on Unemployment of the Adult Education Initiative in Sweden
Authors: Stenberg Anders
Published: March 2005

Abstract.  This paper evaluates the effects on unemployment in Sweden of the Adult Education Initiative (AEI) which during its run from 1997 to 2002 offered adult education to the unemployed at compulsory or upper secondary level. The AEI is compared with the vocational part of Labor Market Training (LMT) using unemployment incidence and unemployment duration as outcome variables, both measured immediately after completion of the programs. For unemployment incidence, selection on unobservables is taken into account by using a bivariate probit model. The analysis of unemployment duration considers both selection bias and censored observations. The results indicate lower incidence following participation in the AEI, but also — significant at the 10 per cent level — longer duration.
Measurement Error and Incentive Pay
Authors: Lehto Eero Lauri Oskari
Published: March 2005

Abstract.  We will analyse the optimal incentive scheme when the risk‐neutral principal contracts with many risk‐averse agents. Each agent produces an individual contribution which jointly form a total output. Agents’ efforts are unobservable and the principal cannot observe individual outputs without an error. Neither the observed individual output of an agent nor the observed total output of the whole team are then sufficient statistics for the actual individual output in the sense of Blackwell. We show that the mixed contract of the pure piece‐rate contract and of the pure team contract then dominates the pure contracts from the principal's point of view.