bluuebunny/crossref_metadata_2025 huggingface dataset:
Depression symptoms in movement disorders: Comparing Parkinson's disease, dystonia, and essential tremor
Authors: Miller Kimberly M. , Okun Michael S. , Fernandez Hubert F. , Jacobson Charles E. , Rodriguez Ramon L. , Bowers Dawn
Published: February 2007

Depression is common in Parkinson's disease (PD) and affects 30 to 50% of all patients. In contrast to the wealth of research on depression in PD, little is known about the occurrence of depression in other movement disorders. The primary objective of the current study was to determine whether the high prevalence of depression symptoms seen in PD is also found in other movement disorders, by directly comparing rates of specific depression symptoms and depression severity across PD, dystonia, and essential tremor (ET). Three hundred and fifty‐four patients with PD, 83 patients with dystonia, and 53 patients with ET completed the Beck Depression Inventory (BDI). We found no significant between‐groups differences for depression severity, frequency, or endorsement of specific depression symptoms. Forty‐eight percent of PD patients, 37.3% of dystonia patients, and 34% of ET patients were found to be at least mildly depressed (BDI score of 10 or higher). The most commonly endorsed symptoms were fatigability, difficulty with work, anhedonia, and sleep disturbance. Clinicians should be aware that depression is a frequent problem in dystonia and ET, in addition to PD, and inquire about depression symptoms in these patients so that they can be appropriately treated © 2007 Movement Disorder Society
Stimulation of subthalamic fibre tracts reduces dyskinesias in STN‐DBS
Authors: Herzog J. , Pinsker M. , Wasner M. , Steigerwald F. , Wailke S. , Deuschl G. , Volkmann J.
Published: February 2007

Rarely, the postoperative management of patients with subthalamic deep brain stimulation (STN‐DBS) is complicated by pharmacologically intractable dyskinesias. Here we report that in three of these patients additional stimulation of a proximal contact located within the subthalamic white matter may lead to a significant reduction of dyskinesias associated with STN‐DBS. We propose that pallidofugal fiber tracts play a major role in the etiopathology of dyskinesias and their blockade through DBS may explain our observations. © 2007 Movement Disorder Society
Memory activation reveals abnormal EEG in preclinical Huntington's disease
Authors: van der Hiele Karin , Jurgens Caroline K. , Vein Alla A. , Reijntjes Robert H.A.M. , Witjes‐Ané Marie‐Noëlle W. , Roos Raymund A.C. , van Dijk Gert , Middelkoop Huub A.M.
Published: February 2007

The EEG is potentially useful as a marker of early Huntington's disease (HD). In dementia, the EEG during a memory activation challenge showed abnormalities where the resting EEG did not. We investigated whether memory activation also reveals EEG abnormalities in preclinical HD. Sixteen mutation carriers for HD and 13 nonmutation carriers underwent neurological, neuropsychological, MRI and EEG investigations. The EEG was registered during a rest condition, i.e. eyes closed, and a working memory task. In each condition we determined absolute power in the theta (4–8 Hz) and alpha (8–13 Hz) bands and subsequently calculated relative alpha power. The EEG during eyes closed did not differ between groups. The EEG during memory activation showed less relative alpha power in mutation carriers as compared to nonmutation carriers, even though memory performance was similar [F (1,27) = 10.87; P = 0.003]. Absolute powers also showed less alpha power [F (1,27) = 7.02; P = 0.013] but similar theta power. No correlations were found between absolute and relative alpha power on the one hand and neuropsychological scores, motor scores or number of CAG repeats on the other. In conclusion, memory activation reveals functional brain changes in Huntington's disease before clinical signs become overt. © 2007 Movement Disorder Society
Reliability of the Burke‐Fahn‐Marsden scale in a multicenter trial for dystonia
Authors: Krystkowiak Pierre , du Montcel Sophie Tezenas , Vercueil Laurent , Houeto Jean‐Luc , Lagrange Christelle , Cornu Philippe , Blond Serge , Benabid Alim‐Louis , Pollak Pierre , Vidailhet Marie ,   The SPIDY Group (French Pallidal Stimulation Group for Dystonia)
Published: February 2007

Background

The multicenter SPIDY trial (pallidal stimulation for generalized, idiopathic dystonia) recently reported a marked improvement in dystonia which was assessed by the Burke‐Fahn‐Marsden (BFM) scale. However, the reliability of this tool has rarely been evaluated and its use in a multicenter study has never been assessed prospectively.

Purpose

To evaluate the concordance between three unblinded clinical raters and one single‐blinded rater for 10 prospective series of ratings on the BFM scale in 22 dystonic patients of the SPIDY study.

Methods

Ten assessments on the BFM scale were performed under various stimulation conditions at different time points (before surgery and 1, 3, 6, and 12 months afterwards). Patients were first evaluated by three unblinded clinical raters (one per center). All assessments were videotaped and sent to a blinded rater. Intra‐ and inter‐rater reliability was assessed using intraclass correlation coefficients.

Results

The intra‐rater reliability at inclusion was better for the blinded rater than for the clinical raters. The inter‐rater reliability (comparing the blinded rater with each clinical rater) was “very good” at inclusion, “fair” at month 1 and was “good” at month 3, month 6, and month 12.

Conclusion

Blinding (rather than video) is probably the key factor in better intra‐rater reliability and can produce more accurate rating than clinical rating. Consequently, a blind procedure should be performed systematically in multicenter studies. As inter‐rater reliability is good in trained unblinded raters, the BFM scale may also be used in the follow up of dystonic patients in movement disorders centers, in clinical practice. © 2007 Movement Disorder Society
Refinement of the DYT15 locus in myoclonus dystonia
Authors: Han Fabin , Racacho Lemuel , Lang Anthony E. , Bulman Dennis E. , Grimes David A.
Published: February 2007

Inherited myoclonus dystonia (MD) is an autosomal dominant disorder in which we previously mapped a novel locus to chromosome18p11 (OMIM number: 607488). Since no further informative STS markers were found within the flanking shared regions, we utilized single nucleotide polymorphisms (SNP) for fine‐mapping. All known or predicted genes within this region were directly sequenced. We identified three recombinant SNPs in the distal region but none from the proximal region. Our previous linked region has now been reduced to 3.18 Mb but direct sequencing of all seven known and four predicted genes with EST support did not identify any mutations. © 2007 Movement Disorder Society
Oxidative stress, chronic disease, and muscle wasting
Authors: Moylan Jennifer S. , Reid Michael B.
Published: February 2007

Underlying the pathogenesis of chronic disease is the state of oxidative stress. Oxidative stress is an imbalance in oxidant and antioxidant levels. If an overproduction of oxidants overwhelms the antioxidant defenses, oxidative damage of cells, tissues, and organs ensues. In some cases, oxidative stress is assigned a causal role in disease pathogenesis, whereas in others the link is less certain. Along with underlying oxidative stress, chronic disease is often accompanied by muscle wasting. It has been hypothesized that catabolic programs leading to muscle wasting are mediated by oxidative stress. In cases where disease is localized to the muscle, this concept is easy to appreciate. Transmission of oxidative stress from diseased remote organs to skeletal muscle is thought to be mediated by humoral factors such as inflammatory cytokines. This review examines the relationship between oxidative stress, chronic disease, and muscle wasting, and the mechanisms by which oxidative stress acts as a catabolic signal. Muscle Nerve, 2007
Anti‐MuSK myasthenia gravis presenting with Epstein–Barr virus‐associated mononucleosis and immune‐mediated diabetes mellitus
Authors: Bhibhatbhan Arunee , Kline Gregory , Vincent Angela , Toth Cory
Published: February 2007

We report a young woman with the abrupt onset of infectious mononucleosis due to Epstein–Barr virus associated with a subsequent autoimmune form of diabetes mellitus and myasthenia gravis with anti–muscle‐specific kinase (MuSK) antibodies. The simultaneous onset of these two autoimmune diseases preceded by a systemic viral illness supports a causal relationship between MuSK antibodies and myasthenia gravis and suggests the possibility of a viral trigger in some cases. Muscle Nerve, 2007
In vivo magnetic resonance spectroscopy of transgenic mouse models with altered high‐energy phosphoryl transfer metabolism
Authors: Renema W. Klaas Jan , Kan Hermien E. , Wieringa Bé , Heerschap Arend
Published: February 2007

Studies of transgenic mice provide powerful means to investigate the in vivo biological significance of gene products. Mice with an under‐ or overexpression of enzymes involved in high‐energy phosphoryl transfer (∼P) are particulary attractive for in vivo MR spectroscopy studies as the substrates of these enzymes are metabolites that are visible in MR spectra. This review provides a brief overview of the strategies used for generation and study of genetically altered mice and introduces the reader to some practical aspects of in vivo MRS studies on mice. The major part of the paper reviews results of in vivo MRS studies on transgenic mice with alterations in the expression of enzymes involved in ∼P metabolism, such as creatine kinase, adenylate kinase and guanidinoacetate methyl transferase. The particular metabolic consequences of these enzyme deficiencies in skeletal muscle, brain, heart and liver are addressed. Additionally, the use of ∼P systems as markers of gene expression by MRS, such as after viral transduction of genes, is described. Finally, a compilation of tissue levels of metabolites in skeletal muscle, heart and brain of wild‐type and transgenic mice, as determined by in vivo MRS, is given. During the last decade, transgenic MRS studies have contributed significantly to our understanding of the physiological role of phosphotransfer enzymes, and to the view that these enzymes together build a much larger metabolic energy network that is highly versatile and can dynamically adapt to intrinsic genotoxic and extrinsic physiological challenges. Copyright © 2007 John Wiley & Sons, Ltd.
Structural topology optimization for the design of broadband dielectric resonator antennas using the finite difference time domain technique
Authors: Nomura Tsuyoshi , Sato Kazuo , Taguchi Kenji , Kashiwa Tatsuya , Nishiwaki Shinji
Published: February 2007

Dielectric resonator antennas (DRAs) are a relatively new class of antenna that utilizes the radiation phenomena of dielectric resonators in open space. Since mainly analytical approaches have been applied to investigate DRA designs, the current DRA forms are limited to simple geometric shapes and high‐performance DRAs with complex shapes have not yet been developed. Topology optimization is capable of yielding high‐performance structures, and has been extensively applied to a variety of structural optimization problems. Applying it to the task of DRA design may be extremely useful for the design of high‐performance antennas. On the other hand, the finite difference time domain (FDTD) method has been used to numerically evaluate general antenna performance, since it is numerically robust during time domain analyses and can handle complex models. Thus, the integration of topology optimization with the FDTD method has the potential to enable innovative designs of advanced antennas that offer exceptional performance. In this research, we propose a new topology optimization method for the design of DRAs that aim to operate with enhanced bandwidths, using the FDTD method. First, the concept of topology optimization is briefly discussed, and a way to integrate topology optimization with the FDTD method is proposed. Next, design requirements are clarified and the corresponding objective functions and the optimization problem are formulated. An optimization algorithm is constructed based on these formulations. Finally, several DRA design examples are presented to confirm the usefulness of the proposed method. Copyright © 2007 John Wiley & Sons, Ltd.
Lysis at the anterior vertebral body margin: evidence for brucellar spondylitis?
Authors: Mays S. A.
Published: February 2007

Recently, palaeopathologists have begun to diagnose brucellosis in skeletal remains from minor lytic lesions located on the anterior margins of one or some few vertebral bodies, taking these lesions to represent brucellar epiphysitis. However, review of the literature indicates that these lesions have been sporadically noted for some time by palaeopathologists and various different interpretations have been placed upon them. In view of this, a study of these vertebral marginal lesions (VML) was undertaken in a large series of archaeological skeletons from England, with the aim of characterising their morphology and frequency and shedding light upon their causes. In the study material, VML were found only in the lumbar spine, where they occurred with a prevalence of approximately 4%. It was argued that VML are consistent with two principal alternative diagnoses: brucellosis and traumatic anterior disc herniation. Differentiating these possibilities for the VML in the study material was difficult, but the balance of the evidence seemed to favour traumatic anterior disc herniation as the more likely cause. It is concluded that VML should not be used to identify the presence of brucellosis in skeletal remains unless there is further evidence, in the form of additional skeletal lesions or biomolecular evidence for residual brucella bacterial DNA, to support such a diagnosis. Copyright © 2007 John Wiley & Sons, Ltd.
Effect of needle diameter on nanofiber diameter and thermal properties of electrospun poly(methyl methacrylate)
Authors: Macossay Javier , Marruffo Alexis , Rincon Roman , Eubanks Tom , Kuang Anxiu
Published: February 2007

The effect of needle diameter on the resulting electrospun poly(methyl methacrylate) (PMMA) average nanofiber diameter has been evaluated for three different needle gauges. The resulting nanofibers were observed and analyzed by scanning electron microscopy (SEM), suggesting a lack of correlation between the needle diameter used and the resulting average nanofiber diameter. Thermogravimetric analysis (TGA) indicated an increase in the thermal stability of PMMA nanofibers when compared to powdered PMMA, while differential scanning calorimetry (DSC) studies evidenced lower glass transition temperatures (Tg) for PMMA nanofibers in the first heating cycle. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis of novel silicone modified acrylic resins and their film properties
Authors: Özgümüş S. , İyim T. B. , Acar I. , Küçükoğlu E.
Published: February 2007

New silicone modified acrylic resins were synthesized and some of their film properties were investigated. At first, macromer (MC) was synthesized by the condensation reaction of the reactive polysiloxane intermediate (Z‐6018) and 2‐hydroxyethyl methacrylate (HEMA) in toluene as solvent at 110°C under nitrogen atmosphere. Then, MC was reacted with 2‐dimethylaminoethyl methacrylate (DMAEMA) at different mole ratios (1:1, 1:3, 1:5) by using benzoyl peroxide as initiator in toluene to obtain novel silicone acrylic resins. These resins were characterized by Fourier Transform Infrared Spectrometry (FT‐IR), and their thermal properties were investigated using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) techniques. The properties of the films prepared from these resins were determined. The results showed that these resins are thermally stable polymers and all films are flexible, semi‐gloss and have excellent drying, adhesion properties. Copyright © 2007 John Wiley & Sons, Ltd.
Biofunctional properties of polyester fibers grafted with chitosan and collagen
Authors: Jou Chi‐Hsiung , Lin Shang‐Ming , Yun Ling , Hwang Mou‐Chuan , Yu Da‐Guang , Chou Wen‐Li , Lee Jui‐Sheng , Yang Ming‐Chien
Published: February 2007

Poly(ethylene terephthalate) (PET) fiber was treated with 60Co‐γ‐ray and grafted with acrylic acid (AA). The resulting fibers were further grafted with chitosan (CS) via esterification. Afterward collagen (COL) was immobilized onto CS‐grafting fibers. The antibacterial activity of CS against Staphylococus aureus, Escherichia coli, and Pseudomonas aeruginosa was preserved after COL‐immobilization. After immobilizing COL, the L929 fibroblasts cell proliferation was promoted than CS‐grafting PET fiber. The results indicate that by grafting with CS and immobilizing with COL, PET fibers exhibited both antibacterial activity against four pathological bacteria and improvement in the proliferation of fibroblast. Copyright © 2007 John Wiley & Sons, Ltd.
The psychosocial impact of parental cancer on children and adolescents: a systematic review
Authors: Osborn Tessa
Published: February 2007

This review aimed to identify (i) whether early stage parental cancer is associated with an increased risk of psychosocial difficulties amongst children and adolescents; (ii) which factors are associated with variations in psychosocial functioning amongst these children and adolescents. Searches of four electronic databases and the reference lists of relevant articles revealed 10 studies which satisfied the inclusion criteria for the first review question and thirteen studies for the second. Limitations in methodological quality and modest numbers of studies examining the same variables, restricted the conclusions which could be drawn. Overall, the evidence suggests that children and adolescents do not generally experience elevated levels of serious psychosocial difficulties compared to reference groups, but they are at a slightly increased risk for internalising type problems. Adolescent daughters appear to be the most negatively affected group. The prevalent use of measures of child psychopathology may be masking more context‐specific problems and lower levels of distress. Family variables, especially family communication/expressiveness, are consistently associated with child/adolescent psychosocial functioning and there is suggestive evidence for the role of maternal depression/adjustment and parenting variables. There is little evidence that medical/treatment variables are important predictors of child outcomes. These findings have implications for identifying families with children most in need of support and indicating variables to target in interventions. Copyright © 2007 John Wiley & Sons, Ltd.
Psychological adjustment of survivors of localised prostate cancer: investigating the role of dyadic adjustment, cognitive appraisal and coping style
Authors: Wootten Addie C. , Burney Sue , Foroudi Farshad , Frydenberg Mark , Coleman Grahame , Ng Kim T.
Published: February 2007

Objectives: The aim of this study was to identify the factors that contribute to psychological adjustment in prostate cancer patients two or more years post‐treatment.

Method: One hundred and sixty‐seven men who had undergone treatment for localised prostate cancer participated in this study. In the sample 63 participants had undergone external beam radiotherapy (EBRT), 55 radical prostatectomy (RP), 27 EBRT plus hormone therapy (EBRT/HT), and the remainder a combination of treatments. Patients completed the UCLA‐PCI, the POMS, CISS, DAS and a threat appraisal questionnaire.

Results: The majority of patients reported relatively positive adjustment in most domains except sexual functioning. For those who reported ongoing psychological difficulty mood disturbance was associated with sexual bother, dyadic adjustment, threat appraisal, self‐efficacy appraisal and emotion‐focussed coping. Lower levels of urinary bother were associated with the use of more task‐focussed coping. Emotion‐focussed coping and threat appraisal mediated the relationship between sexual bother and mood disturbance. Emotion‐focussed coping moderated the influence of dyadic adjustment on mood disturbance.

Conclusions: Dyadic adjustment, threat appraisal and coping style play a significant role in the long‐term psychological adjustment of prostate cancer patients. The results of the current study indicate that the use of emotion‐focussed coping to manage sexual bother appears to result in poor psychological adjustment, which indicates the need for further education or intervention to manage sexual dysfunction.

Ethics Clearance: Human ethics approval was granted from Southern Health, Peter MacCallum Cancer Centre and the Monash University Ethics Committee before commencement of data collection. Copyright © 2007 John Wiley & Sons, Ltd.
X‐ray absorption and molecular dynamics study of cation binding sites in the purple membrane
Authors: Sepulcre Francesc , Cordomí Arnau , Proietti M. Grazia , Perez Juan J. , García Joaquin , Querol Enric , Padrós Esteve
Published: February 2007

The present work describes the results of a study aimed at identifying candidate cation binding sites on the extracellular region of bacteriorhodopsin, including a site near the retinal pocket. The approach used is a combined effort involving computational chemistry methods (computation of cation affinity maps and molecular dynamics) together with the Extended X‐Ray Absorption Fine Structure (EXAFS) technique to obtain relevant information about the local structure of the protein in the neighborhood of Mn2+ ions in different affinity binding sites. The results permit the identification of a high‐affinity binding site where the ion is coordinated simultaneously to Asp212− and Asp85−. Comparison of EXAFS data of the wild type protein with the quadruple mutant E9Q/E74Q/E194Q/E204Q at pH 7.0 and 10.0 demonstrate that extracellular glutamic acid residues are involved in cation binding. Proteins 2007 © 2007 Wiley‐Liss, Inc.
Effect of doping location on photoconductive spectrum of SiGe quantum dots
Authors: Schacham S. E. , Vardi A. , Le Thanh V. , Finkman E.
Published: February 2007

Comparative analysis of photoconductive (PC) spectra obtained from SiGe quantum dots grown on Si shows large dependence on the location of doping. The sample with doping in the silicon barrier has much larger response than the sample in which the doping was placed in the wetting layer, i.e. in the self assembled dots. This is due to the penetration of the wave‐function into the barrier in the first structure, as shown by the 1‐D simulation. Several peaks in the infrared were observed, ranging from 70 to 220 meV, associated with inter‐level transitions of holes in the valance band of the dot or the wetting layer. The overall spectra and the relative intensity of the various peaks change drastically with bias magnitude and polarity. The PC signals increase super‐linearly with bias, indicating that the carriers are released into the quasi‐continuum through tunneling. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Terahertz radiation from coherent confined optical phonons in GaAs/AlAs multiple quantum wells
Authors: Nakayama M. , Mizoguchi K. , Kojima O. , Furuichi T. , Mizumoto A. , Saito S. , Syouji A. , Sakai K.
Published: February 2007

We have investigated the characteristics of the intense terahertz (THz) electromagnetic radiation in (GaAs)35/(AlAs)35 multiple quantum wells with an optical gating method, where the radiation source is coherent longitudinal optical (LO) phonons confined in the GaAs layers. It is found that the intensity of the THz wave from the coherent GaAs‐like LO phonon is enhanced under the condition that the pump‐pulse energy is resonant with the energies of the confined heavy‐hole and light‐hole excitons, which suggests the considerable contribution of the Fröhlich interaction to the generation mechanism. The period‐number dependence of the THz‐wave intensity demonstrates that the THz wave generated in each GaAs layer is constructively superimposed. Moreover, the temperature dependence of the THz‐wave intensity is discussed from an aspect of disturbance by thermal phonons. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Spin‐controlled LEDs and VCSELs
Authors: Hövel S. , Gerhardt N. C. , Brenner C. , Hofmann M. R. , Lo F.‐Y. , Reuter D. , Wieck A. D. , Schuster E. , Keune W.
Published: February 2007

Two different concepts for transferring spin‐optoelectronics to practical room temperature operation devices are explained. First, electrical spin injection in the absence of an external magnetic field and up to room temperature is demonstrated for the first time using Fe/Tb‐multilayers as Schottky‐injectors on common LED‐structures. Complete switching of the polarization from one orientation to the opposite is feasible within ±0.3 T.

Second, the amplification of spin‐information in vertical‐cavity surface‐emitting lasers (VCSELs) is demonstrated by optical test experiments. The output polarization of the VCSEL is unambiguously controlled by the polarized optical excitation. Furthermore, only a spin polarization degree of 30% for the electrons in the active region is required to generate a 100% polarized emission at room temperature for both pulsed and continuous optical excitation.

Finally, we suggest a combination of both concepts in an electrically pumped spin‐VCSEL. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Confinement effects on optical phonons in spherical, rod‐, and tetrapod‐shaped nanocrystals detected by Raman spectroscopy
Authors: Nobile Concetta , Kudera Stefan , Fiore Angela , Carbone Luigi , Chilla Gerwin , Kipp Tobias , Heitmann Detlef , Cingolani Roberto , Manna Liberato , Krahne Roman
Published: February 2007

Spherical, rod‐ and tetrapod shaped CdSe nanocrystals are investigated by Raman spectroscopy and the longitudinal‐optical and surface optical phonons are observed. We find that the position of the longitudinal‐optical phonon slightly red‐shifts with decreasing diameter, whereas the position of the surface optical phonon depends significantly on diameter and length of the rods or the tetrapod arms. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Interface photonic states at the boundary between a metal and a dielectric Bragg mirror
Authors: Shelykh I. A. , Kaliteevskii M. , Kavokin A. V. , Brand S. , Abram R. A. , Chamberlain J. M. , Malpuech G.
Published: February 2007

Tamm states of light are localized interface modes inside the light‐cone. In contrast to the surface modes they can have a zero in‐plane wave‐vector. We show that they can be formed in both TE and TM polarizations at the boundary between the isotropic media with a negative dielectric constant (e.g. a metal below the plasmon resonance) and a periodical dielectric Bragg structure. It is shown that the order of layers in Bragg structure is crucial for the appearance of the Tamm states. The in‐plane dispersion of the interface states is parabolic with effective masses slightly different for TE and TM polarizations, both of the order of 10–5 of the free electron mass. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Synthesis of localized 2D‐layers of silicon nanoparticles embedded in a SiO2 layer by a stencil‐masked ultra‐low energy ion implantation process
Authors: Dumas C. , Grisolia J. , Ressier L. , Arbouet A. , Paillard V. , Ben Assayag G. , Claverie A. , van den Boogaart M. A. F. , Brugger J.
Published: February 2007

We propose an original approach called “stencil‐masked ion implantation process” to perform a spatially localized synthesis of a limited number of Si nanoparticles (nps) within a thin SiO2 layer. This process consists in implanting silicon ions at ultra‐low energy through a stencil mask containing a periodic array of opened windows (from 50 nm to 2 µm). After the stencil removal, a thermal annealing is used to synthesize small and spherical embedded nps. AFM observations show that the stencil windows are perfectly transferred into the substrate without any clogging or blurring effect. The samples exhibit a 3 nm localized swelling of the regions rich in Si nps. Moreover, photoluminescence (PL) spectroscopy shows that due to the quantum confinement only the implanted regions containing the Si nps are emitting light. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Contactless electroreflectance and photoluminescence study of highly strained InGaAs(Sb) double quantum wells
Authors: Hsu H. P. , Korotcov A. , Huang Y. S. , Chen W. C. , Su Y. K. , Tiong K. K.
Published: February 2007

InGaAs(Sb)/GaAs double quantum wells (DQWs) structures grown with Sb assistance under different Sb/V ratios by metalorganic vapor‐phase epitaxy (MOVPE) have been characterized as a function of temperature in the temperature range between 17 and 300 K by the techniques of contactless electroreflectance (CER) and photoluminescence (PL). The interband transition energies are determined via a lineshape fit to the CER spectra and exhibit a slight redshift with the incorporation of Sb. The PL spectra show redshifted peak location with decreasing intensity and broadened full width at half maximum with increasing Sb/V ratio during MOVPE growth. A careful analysis of CER and PL spectra has led to the identification of various excitonic transitions. The anomalous temperature variation of PL spectra has been attributed to the carrier localization effect resulted from the presence of Sb clusters at the QW interfaces. The parameters that describe the temperature dependence of the interband transition energies are evaluated and discussed. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
InGaAs/GaAs quantum wells and quantum dots on GaAs(11n) substrates studied by photoreflectance spectroscopy
Authors: Rojas‐Ramirez J. S. , Yee‐Rendón C. M. , Cruz‐Hernandez E. , Contreras‐Guerrero R. , Vazquez‐Lopez C. , Melendez‐Lira M. , Lopez‐Lopez M.
Published: February 2007

Pseudomorphic InGaAs/GaAs quantum wells (QWs) and self‐assembled InAs quantum dots (QDs) were grown by molecular beam epitaxy (MBE) on GaAs(11n)A substrates. Photoreflectance spectroscopy was employed to investigate the transitions in the heterostructures. The transitions in QWs have two contributions, a blue shift due to the compressive strain, and a red shift due to the quantum confined Stark effect produced by the piezoelectric field. A traditional theoretical interpretation of the QWs transitions employing a simple well model with sharp interfaces shows discrepancies with the experimental results. In order to satisfactorily explain the transitions we proposed to include segregation effects of Indium at the wells interfaces. The matrix transfer method was implemented to numerically solve the Schrödinger equation taking into account In segregation effects by including an asymmetric potential well with a profile depending on the details of the In incorporation. With segregation effects included, the calculated transitions fit very well the PR spectra. On the other hand, the transitions in self‐assembled QDs were obtained by fitting the PR spectra employing a first derivative line‐shape function. For n = 2, 4, 5, two functions were required to fit the spectra. For n = 3 only one function was required, in agreement with the more uniform QDs size distribution observed by atomic force microscopy on GaAs(113)A. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electronic band structure of wurtzite InN around the fundamental gap in the presence of biaxial strain
Authors: Bhattacharyya Jayeeta , Ghosh Sandip
Published: February 2007

We present results of a theoretical study of the electronic band structure of wurtzite InN films under biaxial strain in the C ‐plane (0001) and in planes that correspond to non‐polar orientations such as the A ‐plane (11$ \bar 2 $0) and the M ‐plane (1$ \bar 1 $00). The calculations are performed under the k · p perturbation theory approach using the Bir–Pikus Hamiltonian. The results show that the fundamental bandgap of InN shifts by 30 meV (14 meV) for isotropic tensile (compressive) strain in the C ‐plane with out‐of‐plane contraction (dilation) of 0.2%. For films of non‐polar orientations, the c‐axis lies in the film plane and the strain is expected to be different between directions parallel and perpendicular to c. Such anisotropic strain give rise to valence band mixing which results in dramatic changes in the optical polarization properties as evidenced by the calculated oscillator strengths of the interband transitions. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Modulation spectroscopy of AlGaN/GaN heterostructures: The influence of electron–hole interaction
Authors: Goldhahn R. , Winzer A. T. , Dadgar A. , Krost A. , Weidemann O. , Eickhoff M.
Published: February 2007

A detailed analysis of electroreflectance (ER) spectra for AlGaN/GaN heterostructures containing a two‐dimensional electron gas (2DEG) is presented. The properties of two samples with different Al‐content in the barrier layer are compared. Calculated field‐dependent dielectric functions (DF) for GaN and AlGaN which take into account electron–hole interaction (exciton effects) provide the basis for the modeling of the spectra. It is demonstrated that the Seraphin coefficients exhibit a strong spectral dependence around the gap which cannot be neglected in a fit of ER spectra. The use of the calculated DFs in a multi‐layer model allows to reproduce all peculiarities of experimental ER spectra for both, the GaN channel layer and the AlGaN barrier layer, despite the inhomogeneous field distribution. The determined AlGaN barrier field strengths are very close to the values obtained by applying the asymptotic formulation of the Franz–Keldysh effect. Finally, the polarization gradient at the AlGaN/GaN boundary is estimated from these field strengths. The gradient is slightly lower than theoretically predicted which confirms previous studies. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electroreflectance and photoreflectance spectra of tricolor III‐nitride detector structures
Authors: Drabinska Aneta , Korona K. P. , Pakula K. , Baranowski J. M.
Published: February 2007

Results of photoreflectance and electroreflectance on tunable UV detector are presented. The active region of the detector consists of three layers: GaN, Al0.1Ga0.9N, and Al0.2Ga0.8N. Due to different spontaneous and piezoelectric polarization two‐dimensional electron gases with high electron concentration are formed at each interface. 2D electron gas may be depleted from particular interfaces by applied reverse bias to the Schottky diode. Therefore to the active region of the detector successive layers are enclosed. The photoreflectance spectra show that in “clean” structure low electric field is present in the active region of the detector and on both interfaces the 2D electron gases are present. In electroreflectance measurement with external electric field applied, there is possibility to observe the evolution of the electric field in these layers and the depletion of 2D electron gases from interfaces. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Antinociceptive and antiinflammatory activities of pine (Pinus densiflora) pollen extract
Authors: Choi Eun‐Mi
Published: February 2007

The study aimed to evaluate the antinociceptive and antiinflammatory activity of pine (Pinus densiflora) pollen in mice. The antinociceptive activity was determined using acetic acid‐induced abdominal constriction and formalin‐induced licking, and the hot plate test. Antiinflammatory effects were evaluated using carrageenan‐ and formalin‐induced paw edema, and arachidonic acid‐induced ear edema in mice. The ethanol extract of pine pollen (100 and 200 mg/kg, p.o.) produced a significant inhibition of both phases of the formalin pain test in mice, a reduction in mouse writhing induced by acetic acid and an elevation of the pain threshold in the hot plate test in mice. The pine pollen extract also produced a significant inhibition of carrageenan‐ and formalin‐induced paw edema as well as arachidonic acid‐induced ear edema in mice. The inhibitions were similar to those produced by aminopyrine and indomethacin, p.o. The different polyphenols found in pine pollen could account for the antinociceptive and antiinflammatory actions. The results obtained indicate that the extract possesses analgesic and antiinflammatory effects. Copyright © 2007 John Wiley & Sons, Ltd.
An instrument for recording the rate of rainfall or the wind velocity
Authors: Bibby J. R.
Published: February 2007

An instrument is described which records the number of times an electrical circuit is made and broken in successive two minute intervals. This can be arranged to give an autographic record of the rate of rainfall, or, in conjunction with a cup anemometer, of the wind speed.
The evaluation of the coefficient of eddy diffusivity
Authors: Longley Richmond W.
Published: February 2007

Observational data have been substituted into a modified form of the equation of heat transfer. By a statistical analysis of the resultant equations, values of the coefficient of eddy diffusivity for various stable lapse rates are obtained. It was found necessary in the analysis to define a “point of best fit,” and to derive the normal equations for obtaining this point.
Notes on upper air hygrometry–‐I calculation of the relative humidity from hair hygrometer readings during balloon ascents
Authors: Glückauf E.
Published: February 2007

A method is described for calculating the relative humidity from the data obtainable from balloon hair hygrograph records under conditions in which the hair does not reach equilibrium with its surroundings. Based on and checked by means of laboratory measurements, the method gives consistent results if applied to the Dines meteorograph.
Dynamical control of atmospheric pressure
Authors: Priestley C. H. B.
Published: February 2007

Any dynamical expression for the pressure tendency consists fundamentally of a number of potentially large terms. A mechanism of control is here put forward to explain the fact that the realised pressure tendency invariably emerges as a small residual of its much larger primary components.

The field of flow determines the pressure change, but itself depends dynamically on the instantaneous pressuretendencyfield. It is this mutual interaction between the two fields which constitutes the brake or control on the mutability of the pressure field.

The essential link is the path curvature. The mechanism of control in typical cases may thus be studied by replacing the true wind by the (suitably defined) gradient wind. A number of applications are made with the object of explaining the broad features of the translation of idealisd pressure systems and an indication is given of how the principle may be used to clarify some problems of development.
Notes on the theory of tropical cyclones
Authors: Sawyer J. S.
Published: February 2007

The conditions under which continued outward motion is possible in a circular vortex are investigated theoretically, and the results applied to the development of tropical cyclones, in order to give a possible explanation of the removal of air from the storm centre and the associated fall of pressure.

The development of a storm by this mechanism is described and necessary conditions for such development are found to be:—(a) A lapse rate which will give rise to vertical instability and development of convection cloud. (b) A distribution of circulation at some level aloft such that anticyclonic circulation increases outward at a rate exceeding a certain value. (c) A distribution in the vertical of horizontal rotation such that cyclonic circulation decreases with height.

The importance of horizontal turbulence in producing the calm “eye” of the storm is considered, and the relation between tropical cyclones and fronts is briefly discussed.
Notes on the measurement and estimation of atmospheric radiation
Authors: Robinson G. D.
Published: February 2007

A series of measurements of the infra red emission of the atmosphere has been made at Kew Observatory with Dines and Linke‐Fuessner radiometers. Precautions necessary during the calibration and use of these instruments are discussed, the results obtained with them compared, and the accuracy of the measurements assessed.

Computation of the atmospheric emission by Elsasser's method is discussed, and compared with the experimental results. It is suggested that the divergence found is due to over‐estimation of the emissivity of water vapour in the presence of carbon dioxide by Elsasser, together with the presence of a variable additional component of radiation of from 0 to 8 per cent of the total. Some comments are made on the possible origin of this radiation. A modification of the method of F. A. Brooks is used to derive values of water vapour emissivity from the measurements, and by combining these with the laboratory values of Elsasser and Brooks an emissivity curve is obtained which differs from that now generally accepted. This is used to compute the water vapour radiation, and the construction of an empirical radiation chart is described.

Finally it is shown that the outward radiation of the ground may be obtained from the reading of an ordinary thermometer, and that by combining this with an estimate of atmospheric emission based on routine upper air data, the net infra red radiation of the surface may be estimated with an accuracy better than 15 per cent.
The significance of dynamic instability in atmospheric motions
Authors: Sawyer J. S.
Published: February 2007

A discussion is given of the criterion for a special type of dynamic instability first derived by H. Solberg, viz. :—that the anti‐cyclonic wind shear along an isentropic surface should exceed the coriolis parameter. It is concluded that this criterion has no direct bearing on the formation of extratropical cyclones but it may be important in respect of the limit which it imposes on the wind shear to the south of the “jet stream”. Dynamic instability of this type may also be important in connection with the formation of tropical cyclones and certain features of frontal structure.
Evaporation over the British Isles
Authors: Penman H. L.
Published: February 2007

Theoretical values of average annual evaporation from the British Isles are calculated from long‐term averages of air temperature, duration of sunshine, vapour pressure and wind speed for about 100 stations. Direct estimates of the same quantity are obtained from long‐term averages of annual rainfall and annual run‐off from about 40 catchment areas. The two kinds of estimate agree and are plotted on a map to show the geographical variation of evaporation. This shows an increase from 14 in. per annum in Scotland to 20 in. along the south coast.
The significance of vertical stability in synoptic development
Authors: Sumner E. J.
Published: February 2007

The connection between the development of depressions and anticyclones and the degree of vertical stability of the atmosphere is examined. It is concluded that in middle latitudes the damping due to stability is not important in the largest‐scale circulations of diameter greater than about 2,000 km, but has controlling significance for systems of diameter less than about 1,000 km. The difference in the rate of development between an ordinarily stable and a neutral atmosphere may be ten‐fold or more for the smaller systems. A very small degree of instability in depth will permit small‐scale cyclonic development to proceed rapidly.

Furthermore, the damping effect of atmospheric stability is inversely proportional to the square of the Coriolis parameter. At 10° latitude, for example, the effect becomes dominant for all practical diameters, and it would appear difficult for cyclones or anticyclones of any reasonable size to develop significantly in low latitudes, with the exception of cyclones in a vertically unstable atmosphere.
Types and spells of weather around the year in the British Isles : Annual trends, seasonal structure of the year, singularities
Authors: Lamb H. H.
Published: February 2007

From a classification of 50 years' daily weather maps (1898—1947) the outstandingly long spells of weather, lasting over 25 days, have been picked out. Frequency curves show the occurrences of these long spells on each day of the year and also the occurrences of each of the seven defined weather‐types individually. This leads to a suggested division of the year into five periods, to be considered as natural seasons, and appears to support the definition of more numerous shorter seasonal phases or episodes (singularities). Good correspondence is found with the long‐year daily or weekly mean figures of pressure, temperature, rainfall, sunshine, etc. The significance of these phenomena, their dependability as regards date and their secular persistence are discussed.
Recent work of the Thunderstorm Census Organisation
Authors: Morris Bower S.
Published: February 2007

The weakness of the definition of a day with a thunderstorm as any civil day on which thunder is heard at a station, and the great difficulty of interpreting data on such a basis, is illustrated. An example of a thunderstorm chart based on the daily areas of overhead thunderstorms drawn from a close network of recording stations is presented and is compared with the “thunder‐heard” results. A method of producing detailed period and average maps, published as County Thunderstorm Surveys, is shown. The similar charting of daily areas of lightning damage provides a convenient and reliable method of examining the distribution of storm severity, and has many practical applications.

Analyses of thunderstorms on individual days by means of hourly isochrones, published as Daily Thunderstorm Charts, present new opportunities for detailed comparison with rainfall maps and with radio thunderstorm recordings.
The lag of temperature behind solar radiation
Authors: Prescott J. A. , Collins Joyce A.
Published: February 2007

The annual march of air and sea surface temperatures has been examined by harmonic analysis and characterised by mean and amplitude and first harmonic value of phase. The phase has been expressed as the lag of temperature behind solar radiation and the data so obtained have been transferred to two world maps. A more detailed map relating to air temperatures over the United States is also given.

Coastal stations are late in phase and inland basins are earliest. Western margins of the continents show a substantially later phase than eastern margins. This is associated with a tendency towards a late phase in the sea surface temperatures of the eastern sections of the oceans.
Note on the seasonal variation of the meridional flux of angular momentum
Authors: Starr V. P. , White R. M.
Published: February 2007

A marked seasonal variation of the poleward angular‐momentum flux for the northern hemisphere in the vicinity of 30°N. latitude is obtained from an analysis of upper‐wind soundings for a period of one year. The angular‐momentum flux appears to be about twice as great during the winter as during the summer. Indications of a mean meridional circulation of the strength and character necessary to provide a substantial flux of angular momentum are lacking. It is suggested that the horizontal eddy flux of angular momentum across 30°N. latitude is sufficient to account for the drain of this momentum in middle latitudes.
Sonic and advective disturbances
Authors: Scorer R. S.
Published: February 2007

This paper describes the role of sonic disturbances in redistributing the mass of the atmosphere when heating or cooling is applied to a part of it. It is shown that the effect, for meteorological purposes, of heating is a local reduction of density and surface pressure. The pressure field thus set up causes an advective disturbance which later modifies the field by transport of mass with the wind.

It is concluded that no disturbance of meteorological significance ever travels from one place to another otherwise than by advection.