bluuebunny/crossref_metadata_2025 huggingface dataset:
Pilot clinical study of a novel minimally invasive bipolar microneedle radiofrequency device
Authors: Hantash Basil M. , Renton Bradley , Berkowitz R. Laurence , Stridde Braden C. , Newman James
Published: February 2009

Background and Objectives

Noninvasive bipolar and monopolar radiofrequency (RF) deep dermal heating devices have previously been described. A novel minimally invasive RF device employing a bipolar microneedle electrode system is introduced and its resultant thermal effects on human skin in vivo were characterized for the first time.

Study Design/Materials and Methods

An investigational 35 W RF device was configured to operate in bipolar mode delivering energy directly within the dermis using 5 microneedle electrode pairs with real‐time feedback of tissue temperature for treatment control. Superficial cooling was achieved using a Peltier device. A range of pulse durations between 1 and 25 seconds, and lesion temperatures between 60 and 80°C were tested in vivo on 15 human subjects. Thermal effects were assessed histologically using either hematoxylin & eosin (H&E) or nitroblue‐tetrazoliumchloride (NBTC) staining. Treatment effects and adverse events were also monitored clinically.

Results

The investigational bipolar RF device delivered controlled heating within dermal tissue. Histological staining with H&E revealed the presence of zones of denatured collagen within the reticular dermis. Lesions were generated at preselected temperatures between 60 and 80°C. Fractional lesions separated by zones of sparing as well as contiguous lesion patterns were demonstrated. Histological staining with H&E and NBTC revealed sparing of adnexal structures and adipose tissue. No major adverse events were observed.

Conclusions

A novel fractional RF device utilizing a minimally invasive bipolar microneedle delivery system for the treatment of human tissue was developed. Treatment of 15 human subjects illustrated the controlled creation of dermally located thermal coagulation zones, herein known as radiofrequency thermal zones. We discovered that varying the pulse length allowed for fractional sparing of dermal tissue. To our knowledge, this is the first report to describe use of a direct real‐time temperature and impedance feedback system to control energy delivery during deep dermal heating. Lasers Surg. Med. 41:87–95, 2009. © 2009 Wiley‐Liss, Inc.
The effects of multiple passes on the epidermal thermal damage pattern in nonablative fractional resurfacing
Authors: Manstein Dieter , Zurakowski David , Thongsima Siremon , Laubach Hans , Chan Henry H.
Published: February 2009

Background and Objective

Nonablative fractional resurfacing is a concept of cutaneous re‐modeling whereby laser‐induced microscopic treatment zones (MTZs) are surrounded by normal viable tissue. Such thermal damage pattern with a small diameter of individual lesions allows fast re‐epithelialization with minimal side effects. The purpose of this in vitro study was to determine the fraction of thermal injury per unit surface area (fill factor) and lesion size in relation to pulse energy and number of passes.

Methods

Full thickness abdominal skin samples were exposed ex vivo to the Fraxel SR 750 laser (Reliant Technologies, Mountain View, CA). One set of exposures was performed for pulse energies in the range of 8 to 40 mJ for a single pass at 250 MTZ/cm2. A second set of exposures was performed at 10 mJ with number of passes from 1 to 30. The thermal damage pattern was assessed by incubation of epidermal sheets with NitroBlueTetrazoliumChloride (NBTC) stain. Size of individual MTZ and fill factor were determined by image analysis (ImageJ, NIH, Bethesda, MD) of digital micrographs.

Results

Width of the thermal injury zone was directly related to the pulse energy used. The fill factor did not have a uniform relationship with the number of passes. Due to the stochastic placement of individual MTZs, even for greater number of passes, some residual undamaged tissue was found. Due to formation of thermal damage clusters, defined as overlapping individual MTZs, the size of the resulting clustering lesions which we defined as microscopic treatment cluster (MTC) increased linearly as a function of the number of passes.

Conclusion

We have described the fill factor as it relates to the number of passes and have demonstrated that the average size of individual lesions depends on the number of passes. Clustering of MTZs lead to the development of MTC, the average size of which increased with the number of passes. The clinical implications of these findings are contingent on further studies. Lasers Surg. Med. 41:149–153, 2009. © 2009 Wiley‐Liss, Inc.
Fractional deep dermal ablation induces tissue tightening
Authors: Rahman Zakia , MacFalls Heather , Jiang Kerrie , Chan Kin F. , Kelly Kristen , Tournas Joshua , Stumpp Oliver F. , Bedi Vikramaditya , Zachary Christopher
Published: February 2009

Background and Objective

Due to the significant risk profile associated with traditional ablative resurfacing, a safer and less invasive treatment approach known as fractional deep dermal ablation (FDDA™) was recently developed. We report the results of the first clinical investigation of this modality for treatment of photodamaged skin.

Study Design/Materials and Methods

Twenty‐four subjects received treatments on the inner forearm with a prototype fractional CO2 laser device (Reliant Technologies Inc., Mountain View, CA) at settings of 5–40 mJ/MTZ and 400 MTZ/cm2. Clinical and histological effects were assessed by study investigators 1 week, 1 month, and 3 months following treatment. Thirty subjects were then enrolled in a multi‐center study for treatment of photodamage using the same device. Subjects received 1–2 treatments on the face and neck, with energies ranging from 10 to 40 mJ/MTZ and densities ranging from 400 to 1,200 MTZ/cm2. Study investigators assessed severity of post‐treatment responses during follow‐up visits 48 hours, 1 week, 1 month, and 3 months following treatment. Using a standard quartile improvement scale (0–4), subjects and investigators assessed improvement in rhytides, pigmentation, texture, laxity and overall appearance 1 and 3 months post‐treatment.

Results

Clinical and histologic results demonstrated that fractional delivery of a 10,600 nm CO2 laser source offers an improved safety profile with respect to traditional ablative resurfacing, while still effectively resurfacing epidermal and dermal tissue. Forearm and facial treatments were well‐tolerated with no serious adverse events observed. Eighty‐three percent of subjects exhibited moderate or better overall improvement (50–100%), according to study investigator quartile scoring.

Conclusions

FDDA™ treatment is a safe and promising new approach for resurfacing of epidermal and deep dermal tissue targets. Lasers Surg. Med. 41:78–86, 2009. © 2009 Wiley‐Liss, Inc.
Optimal pulse durations for the treatment of leg telangiectasias with an alexandrite laser
Authors: Ross E.V. , Meehan K.J. , Gilbert S. , Domankevitz Y.
Published: February 2009

Background and Objectives

Determine optimal settings using a long pulse 755 nm alexandrite laser in the treatment of superficial leg veins.

Study Design\Materials and Methods

Fifteen patients with Fitzpatrick skin types I–III with telangiectasia ranging from 0.2 to 1.0 mm were enrolled. Spot size varied from 3 to 6 mm. Pulse durations ranged from 3 to 100 milliseconds. For each pulse duration, test sites were performed to determine threshold radiant exposures using persistent bluing and/or immediate stenosis (closure) as the clinical endpoint. Test sites were re‐evaluated 21 days later. Optimal settings, those that resulted in the greatest clearance with minimal side effects (pain, purpura, epidermal damage, pigment changes), were used to treat a larger area of like‐sized vessels. Follow‐up evaluations were conducted 12 weeks after a single treatment using the optimal setting. Polarized digital photographs were obtained at each visit. Improvement was determined by blinded evaluation of pre/post‐treatment photographs.

Results

Fourteen patients completed the study. Radiant exposure thresholds for immediate vessel changes depended on vessel diameter, with larger radiant exposures required for smaller spot sizes and smaller vessels. The average threshold radiant exposure for closure was 89 J/cm2. The optimal pulse duration was 60 milliseconds for most of the patients. With this pulse width, clearance approached 65% 12 weeks after a single treatment. Transient hyperpigmentation occurred in four patients. Increasing the pulse duration improved epidermal tolerance and decreased the likelihood of purpura.

Conclusions

By lengthening the pulsewidth beyond 3 milliseconds, a long pulse alexandrite laser achieves satisfactory clearance with an improved side effect profile. Lasers Surg. Med. 41:104–109, 2009. © 2009 Wiley‐Liss, Inc.
Fluorescence detection and diagnosis of non‐melanoma skin cancer at an early stage
Authors: de Leeuw Jaap , van der Beek Nick , Neugebauer W. Dieter , Bjerring Peter , Neumann H.A. Martino
Published: February 2009

Background

The occurrence of non‐melanoma skin cancer (NMSC), including actinic keratosis (AK) is increasing all over the world. The detection and diagnosis of NMSC is not optimal in clinical practice. Complementary methods for detection and accurate demarcation of NMSC at an early stage are needed in order to limit the damage caused by tumours.

Objective

The purpose of the present study was to use a large area skin fluorescence detection system to detect early NMSCs (clinical visible as well as non‐visible lesions) in the face, neck, chest, back and hands of patients treated with UV and outdoor workers.

Methods

Fluorescence detection with a purpose‐made digital camera and software (Dyaderm®) combined with 5‐aminolevulinic acid (5‐ALA) encapsulated in liposomes.

Results

In 93 consecutively referred patients positive skin fluorescence was detected in 61 patients. After histological examination the positive fluorescence appeared to be correlated to benign lesions in 28 patients (sebaceous gland hyperplasia in 22 patients) and to (pre‐) malignant lesions in 33 patients (actinic keratosis in 29, BCC in 3 and SCC in 1 patient). False negative fluorescence was found in only one lesion. In five patients the FD technique used in this study appeared to be more sensitive for the identification of (pre‐) malignant lesions than the clinical examination. This is in contrast with FD techniques used in previous studies.

Conclusion

Diagnostic skin fluorescence using liposomal encapsulated 5‐ALA and a specialised computerised detection and visualisation system offers the possibility for detection of NMSC at an early, pre‐clinical stage. The technique is well suited to examine large areas of skin. It also identifies areas of most interest for performing confirmatory skin biopsies, as well as pre‐operative assessment of boundaries of skin malignancies, and finally, the technique is applicable in the control and follow‐up of skin cancer treatment. Lasers Surg. Med. 41:96–103, 2009. © 2009 Wiley‐Liss, Inc.
Specific pH‐Responsive Folate‐Conjugate Microgels Designed for Antitumor Therapy
Authors: Pérez‐Alvarez Leyre , Sáez‐Martínez Virginia , Hernaez Estíbaliz , Herrero M. , Katime Issa
Published: February 2009

Colloidal nanosized folate‐conjugated hydrogels for targeted chemotherapy were prepared via a versatile and efficient postsynthetic modification pathway starting from P(NPA‐co‐NIPAM). The modifications included the introduction of 4‐methylpyridine as pH‐sensitive pendant groups and the conjugation of folic acid to the microgel network. The microgels showed a specific swelling at pH < 6 (endosomes) as judged by DLS studies varying the external pH. The relative composition of the microgels shows a clear influence on the pH volume transition shifting. The potential of the microgels for anticancer drug release at pH = 5.0 was confirmed. Therefore, they are a promising targeting carrier for improved anticancer chemotherapy.

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Multifunctional xGnP/LLDPE Nanocomposites Prepared by Solution Compounding Using Various Screw Rotating Systems
Authors: Kim Sumin , Do Inhwan , Drzal Lawrence T.
Published: February 2009

xGnP‐Reinforced LLDPE nanocomposites have been prepared using co‐, counter‐ and modified co‐rotating screw systems. The highest tensile strength and modulus were shown in the case of composites made by counter‐rotating screws. The percolation threshold of exfoliated graphite nanoplatelet/LLDPE nanocomposites was between 12 and 15 wt.‐%. The change of crystallinity caused by exfoliated graphite nanoplatelet loading was monitored using DSC and XRD. It was found that solution mixing showed better dispersion of exfoliated graphite nanoplatelets than melt mixing, and counter‐rotating screws produced better dispersion of the exfoliated graphite nanoplatelets than co‐ and modified co‐rotating screws even though bubbling appeared during mixing in the barrel.

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A Template‐Free Method toward Urchin‐Like Polyaniline Microspheres
Authors: Wang Junsheng , Wang Jixiao , Wang Zhi , Zhang Fengbao
Published: February 2009

Urchin‐like PANI microspheres with an average diameter of 5–10 µm have been successfully prepared. Their surfaces consist of highly oriented nanofibers of ≈30 nm diameter and 1 µm length. The solvent composition plays an important role in the formation process of urchin‐like PANI microspheres. The structure of the products has been characterized by FT‐IR, UV‐vis, and XRD. To investigate the self‐assembly of urchin‐like PANI microspheres, the effect of polymerization time on the morphology of the products has been studied. The morphological evolution process indicates that the urchin‐like microspheres originate from the self‐assembly of nanoplates, which then grow into urchin‐like microstructures with nanofibers on the surface.

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Macromol. Theory Simul. 2/2009
Authors: Camesasca Marco , Manas‐Zloczower Ica
Published: February 2009

Cover: Illustration of the use of Rényi entropies to characterize both the scale and intensity of segregation in a two‐component system: the higher the global minimum at the same resolution, the smaller the intensity of segregation; the smaller the resolution (linear bin size) at which the global minimum occurs, the smaller the scale of segregation. Further details can be found in the article by M. Camesasca, and I. Manas‐Zloczower* on page 87.
Low‐frequency scattering by a penetrable body with an eccentric soft or hard core
Authors: Lucas‐Lekatsas John , Kostopoulos Vassilis
Published: February 2009

A plane wave is scattered by an acoustically soft or hard sphere, covered by a penetrable non‐concentric spherical lossless shell that disturbs the propagation of the incident wave field. The dimensions of the coated sphere are much smaller than the wavelength of the incident field. Low‐frequency theory reduces this scattering problem to a sequence of potential problems, which can be solved iteratively. Exactly one bispherical coordinate system exists that fits the given geometry of the obstacle. For the case of a soft and hard core, the exact low‐frequency coefficients of the zeroth and the first‐order for the near field as well as the first‐ and second‐order coefficients for the normalized scattering amplitude are obtained and the cross sections are calculated. Discussion of the results and their physical meaning is included. Copyright © 2009 John Wiley & Sons, Ltd.
A review of complementary and alternative medicine (CAM) by people with multiple sclerosis
Authors: Olsen Sherri A.
Published: February 2009

Multiple sclerosis (MS) is a chronic, unpredictable disease of the central nervous system without a known cure. Because of this, people with MS often seek complementary and alternative medicines (CAM) to manage their disease symptoms. The goal of this review article was to describe the use of CAM by individuals diagnosed with MS. Evidence was obtained by searching Medline (1950–2007), EBSCOhost and PubMed for studies relating CAM to MS. Results from the literature showed that people with MS reported that they used CAM from 27 to 100%. The major reasons for choosing CAM were as follows: conventional treatment was not effective, anecdotal reports of CAM's help, and doctor referral. The types of CAM reported by people with MS included exercise, vitamins, herbal and mineral supplements, relaxation techniques, acupuncture, cannabis and massage. The major symptoms treated by CAM as noted in the literature were pain, fatigue and stress. There is a need for further research to evaluate the effectiveness of CAM with MS patients and their application by occupational therapists. The limitation of this literature review was the low response rate in many of the surveys reported. Copyright © 2009 John Wiley & Sons, Ltd.
The predictive value of 18 and 22 week uterine artery Doppler in patients with low first trimester maternal serum PAPP‐A
Authors: Cooper Stephanie , Johnson Jo‐Ann M. , Metcalfe Amy , Pollard Jeffery , Simrose Rebecca , Connors Gregory , Jones Donna , Roggensack Anne , Krause Richard , Lange Ian
Published: February 2009

Objective

To determine if the addition of uterine artery (UA) Doppler pulsatility index (PI) at 18 and 22 weeks of gestation improves the predictive accuracy of low first trimester pregnancy associated plasma protein A (PAPP‐A) in the detection of adverse obstetrical outcomes.

Methods

This was a prospective interventional study. All women undergoing first trimester combined screening (FTS) at a single center, with a low maternal serum PAPP‐A level (<0.4 MoM), were included. Patients underwent bilateral UA Doppler assessments at 18 and 22 weeks of gestation. A positive test was defined as a mean PI > 1.45. Primary outcomes were obtained from chart review, and logistic regression analysis was used to compare outcomes with positive and negative tests. Positive and negative predictive value, specificity and sensitivity were calculated.

Results

Between January and October 2007, 5359 women completed FTS. Among the low PAPP‐A group (n = 289), 18 week UA Doppler was a significant predictor of low birth weight (OR = 2.28, p = 0.04) while 22 week UA Doppler significantly predicted preterm birth (OR = 12.6, p = 0.001), small for gestational age (OR = 8.24, p = 0.001) and low birth weight (OR = 2.28, p = 0.04). Test characteristics suggested improved positive and negative predictive value for Doppler at 22 versus 18 weeks for these outcomes.

Conclusions

UA Doppler at 22 weeks is a useful adjunct in patients with low PAPP‐A. However, a negative Doppler does not rule out all adverse outcomes and clinical judgment is advised in the management of these patients. Copyright © 2009 John Wiley & Sons, Ltd.
Impact of antiphosholipid biology in maternal Down syndrome screening
Authors: Brochet Christine , Morin Nathalie , Coudert Mathieu , Vauthier‐Brouzes Danièle , Costedoat‐Chalumeau Nathalie , Bernard Maguy
Published: February 2009

Objective

Women with antiphospholipid (aPL) biology present obstetric complications. The α‐fetoprotein (AFP) serum levels of these patients are higher than in general population. Because AFP is involved in the calculation of the risk of trisomy 21 (T21), we studied the effect of AFP variations in the presence of aPL during T21 screening.

Methods

The study group (aPL group) was comprised of 64 pregnancies in women with aPL antibodies. The control group was comprised of 21 655 pregnancies included in the national program for routine Down syndrome (DS) screening by maternal serum markers [human chorionic gonadotrophin (hCG) and AFP] between 14 + 0 and 18 + 6 weeks of gestation.

Results

AFP values, converted in logarithm of multiples of the median (MoM), were significantly higher in the aPL group (0.03 vs 0.10; p = 0.018). After a matricial transformation of AFP MoM and hCG MoM in the aPL group, new T21 risks presented a median of one in 1665 versus one in 2574 (p < 0.0001 with a rank‐sign test).

Conclusion

Our results highlight the fact that in the presence of aPL antibodies, the calculated risk of T21 is underestimated. Therefore, clinicians should interpret the screening borderline results in aPL patients with caution. Copyright © 2009 John Wiley & Sons, Ltd.
A strategy for identifying circulating placental RNA markers for fetal growth assessment
Authors: Pang Winnie W. I. , Tsui Michelle H. Y. , Sahota Daljit , Leung Tak Y. , Lau Tze K. , Lo Y. M. Dennis , Chiu Rossa W. K.
Published: February 2009

Objective

To evaluate whether circulating placental mRNAs in maternal plasma could serve as markers for the assessment of fetal growth or intrauterine growth restriction (IUGR).

Methods

From a panel of placental transcripts detectable in maternal plasma identified by microarray previously, we chose growth‐related transcripts, namely CSH1, GH2, KISS1, and ADAM12, as potential growth markers. Relationships between the maternal plasma mRNA concentrations with several fetal growth indicators were studied. Maternal plasma mRNA concentrations from IUGR pregnancies with or without pre‐eclampsia (PET) were compared with gestational age matched controls cross‐sectionally and longitudinally. The four transcripts were quantified by one‐step real‐time RT‐PCR.

Results

Maternal plasma GH2 mRNA significantly correlated with birth weight and fetal biometric measurements. Maternal plasma ADAM12 mRNA concentration was significantly higher in IUGR with PET than normal pregnancies in the cross‐sectional comparison. No significant difference was observed for all markers between IUGR without PET and controls in both the cross‐sectional and longitudinal comparisons.

Conclusion

This study presents a potential strategy in identifying surrogate markers for the study of fetal growth. Circulating GH2 mRNA in maternal plasma appeared to be associated with fetal growth. The utility of this strategy and the currently assessed markers could be explored in further studies. Copyright © 2009 John Wiley & Sons, Ltd.
Synthesis and photochromic properties of crown‐containing styryl derivatives of naphthopyrans
Authors: Glebov Evgeni M. , Smolentsev Artjom B. , Korolev Valeri V. , Plyusnin Victor F. , Chebunkova Anna V. , Paramonov Sergei V. , Fedorova Olga A. , Lokshin Vladimir , Samat Andre
Published: February 2009

New crown‐containing and crownless chromenes were synthesized. Their physical properties and photochemistry were characterized. Crown‐containing chromenes form inclusion complexes with Mg2+ cation. Two types of photochemical reactions were observed for all the studied chromenes. The photoreaction of the first type is cis–trans isomerization of styryl fragment in closed form. Second type of photoreaction is the reversible formation of open form responsible for the photochromism of chromenes. Arrhenius parameters of back reactions are determined. Both crownless and crown‐containing chromenes do not demonstrate cation‐dependent photochromism, which is explained by the peculiarities of the structure of open form. Copyright © 2009 John Wiley & Sons, Ltd.
A novel topology for representing protein folds
Authors: Segal Mark R.
Published: February 2009

Various topologies for representing 3D protein structures have been advanced for purposes ranging from prediction of folding rates to ab initio structure prediction. Examples include relative contact order, Delaunay tessellations, and backbone torsion angle distributions. Here, we introduce a new topology based on a novel means for operationalizing 3D proximities with respect to the underlying chain. The measure involves first interpreting a rank‐based representation of the nearest neighbors of each residue as a permutation, then determining how perturbed this permutation is relative to an unfolded chain. We show that the resultant topology provides improved association with folding and unfolding rates determined for a set of two‐state proteins under standardized conditions. Furthermore, unlike existing topologies, the proposed geometry exhibits fine scale structure with respect to sequence position along the chain, potentially providing insights into folding initiation and/or nucleation sites.
Design of stable α‐helices using global sequence optimization
Authors: Petukhov Michael , Tatsu Yoshiro , Tamaki Kazuyo , Murase Sachiko , Uekawa Hiroko , Yoshikawa Susumu , Serrano Luis , Yumoto Noboru
Published: February 2009

The rational design of peptide and protein helices is not only of practical importance for protein engineering but also is a useful approach in attempts to improve our understanding of protein folding. Recent modifications of theoretical models of helix‐coil transitions allow accurate predictions of the helix stability of monomeric peptides in water and provide new possibilities for protein design. We report here a new method for the design of α‐helices in peptides and proteins using AGADIR, the statistical mechanical theory for helix‐coil transitions in monomeric peptides and the tunneling algorithm of global optimization of multidimensional functions for optimization of amino acid sequences. CD measurements of helical content of peptides with optimized sequences indicate that the helical potential of protein amino acids is high enough to allow formation of stable α‐helices in peptides as short as of 10 residues in length. The results show the maximum achievable helix content (HC) of short peptides with fully optimized sequences at 5 °C is expected to be ∼70–75%. Under certain conditions the method can be a powerful practical tool for protein engineering. Unlike traditional approaches that are often used to increase protein stability by adding a few favorable interactions to the protein structure, this method deals with all possible sequences of protein helices and selects the best one from them. Copyright © 2009 European Peptide Society and John Wiley & Sons, Ltd.
Alloy softening in a martensitic stainless steel
Authors: Gupta C. , Chakravartty J. K.
Published: February 2009

A study of the tensile flow behavior in the microstrain region of a martensitic stainless steel within the temperature range 77–273 K has been carried out. The ductility and work hardening in the low‐temperature region were found to be significantly larger than those of the ambient at temperatures where alloy softening was taking place. Thermal‐activation analysis of data has attributed the low‐temperature deformation behavior to the operation of the Peierls mechanism. While the Dorn–Rajnak model was found to fit the data, the observed alloy softening was attributed to the operation of an intrinsic mechanism that promoted the double‐kink formation on dislocations within a limited temperature range below ambient. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Light soaking effect on photocurrent collection in (Zn,Mg)O/Cu(In,Ga)Se2 solar cells
Authors: Minemoto Takashi , Hori Hiroaki , Takakaura Hideyuki
Published: February 2009

The metastable behaviour, so‐called light soaking (LS) effect, on (Zn,Mg)O (ZMO)/Cu(In,Ga)Se2 (CIGS) solar cells with controlled conduction band offset (CBO) values of the ZMO/CIGS layers was characterized. When the conduction band of ZMO is higher than that of CIGS, which creates the notch of the ZMO/CIGS interface in the conduction band, metastable current‐voltage curves were observed. The metastability becomes prominent with increasing the CBO value. Quantum efficiency measurements before and after the LS revealed that the LS effect was mainly originated by the metastability in the photocurrent collection which influenced by the notch acting as a barrier for photo‐generated electrons in the CIGS layer. The model for the LS effect is discussed with simulated energy band diagrams. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Cu(In,Ga)S2 films prepared by two‐stage evaporation on ZnO coated substrates
Authors: Kaigawa R. , Morimoto A. , Funahashi K. , Fujie R. , Wada T. , Sasaki M. , Merdes S. , Klenk R.
Published: February 2009

We have prepared Cu(In,Ga)S2 films with an almost homogeneous Ga depth distribution using the two‐stage multi‐source evaporation process on soda lime glass (SLG) substrates with one of three different kinds of back contact: Mo(1000nm), ZnO(500nm), and Mo(30nm)/ZnO(500nm), respectively. We have investigated the depth profiles of Zn and Na (diffused from SLG) in Cu(In,Ga)S2 films by secondary ion mass spectroscopy (SIMS) and compare them to those in films prepared by single stage co‐evaporation. The efficiencies are higher on Mo/ZnO than they are on ZnO. It was observed by SIMS that the amount of Zn in Cu(In,Ga)S2 on Mo/ZnO is lower than it is in Cu(In,Ga)S2 on ZnO. The obtained efficiencies are generally higher with two‐stage evaporation than with single stage co‐evaporation. The Na concentration in Cu(In,Ga)S2 prepared by two‐stage evaporation is two orders of magnitude higher than in single stage co‐evaporated films. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Optical properties of Sn‐doped and Sn:Ce‐codoped CaAl2S4 and application to white light emitting phosphor
Authors: Sorimachi Hiroshi , Ohta Hitoshi , Tanaka Kunihiko , Uchiki Hisao
Published: February 2009

Sn‐doped CaAl2S4 polycrystals and single crystals were synthesized by solid state reaction and chemical transport reaction method, respectively. They showed broad photoluminescence (PL) spectra in the visible region under the ultraviolet excitation and their luminescence color was pale yellow under the excitation at 325 nm. Three excitation bands at 3.67, 3.80, and 3.91 eV and three emission bands at 1.75, 1.93, and 2.15 eV were observed in photoluminescence excitation and PL spectra at 16 K. These bands were attributed to Sn ions which formed Tl+‐type impurity center. For the application to white LED, Ce was co‐doped into CaAl2S4:Sn polycrystals to enhance blue emission. As a result, Sn (0.5 mol%) and Ce (0.5 mol%) co‐doped CaAl2S4 polycrystals showed white luminescence with chromatic coordinates of (0.393, 0.392) and (0.364, 0.343) under the excitation at 325 and 330 nm, respectively. The highest quantum efficiency of 43% was obtained for Sn (0.1 mol%) and Ce (0.5 mol%) co‐doped CaAl2S4 polycrystals under 320 nm excitation. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Growth of Ge and P codoped p ‐type CuInS2 bulk crystals
Authors: Kato Takamasa , Yamaguchi Hiroshi , Muranaka Tsutomu , Nabetani Yoichi , Matsumoto Takashi
Published: February 2009

Codoping of Ge and P into CuInS2 was carried out in order to grow p ‐type CuInS2 bulk crystals reproducibly in the S‐poor alloy composition region. The codoping condition for p ‐type crystal growth was made clear for the growth temperatures of 850 and 900 °C. The electrical and photoluminescence properties of codoped p ‐type crystals were also studied. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Temperature dependence of excitonic emission in CuInSe2
Authors: Yakushev M. V. , Martin R. W. , Mudryi A. V.
Published: February 2009

Radiative recombination processes in CuInSe2 (CIS) single crystals grown by the vertical Bridgman technique were studied using photoluminescence (PL) and reflectance (RF) spectroscopies at temperatures from 4.2 to 60 K, and excitation intensity from 0.6 to 30 W/cm2. Study of the quenching parameters of the A and B free‐ and first three bound‐excitons (M1, M2 and M3) in high‐quality CuInSe2 single crystal leads to estimates for the binding energy of the A (7.7 meV) and B (7.9 meV) free excitons as well as dissociation energies for the M1, M2 and M3 bound‐excitons. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Multi‐platform observations of a springtime case of Bodélé and Sudan dust emission, transport and scavenging over West Africa
Authors: Flamant C. , Lavaysse C. , Todd M. C. , Chaboureau J.‐P. , Pelon J.
Published: February 2009

The structure of the Saharan air layer over Niger and Benin during a major springtime dust event from the Bodélé region and Sudan is investigated using airborne lidar and dropsonde measurements. Aircraft operations were conducted on 13 and 14 June 2006, within the framework of the African Monsoon Multidisciplinary Analysis Special Observing Period. Complementary ground‐based and satellite observations, as well as European Centre for Medium‐range Weather Forecasts analyses are used to investigate the regional aspects of emission, transport and deposition in the period from 9 to 14 June 2006, to provide a framework for the interpretation of the airborne measurements. The study details the transport patterns of dust from eastern Saharan sources towards the southwest in the springtime, and highlights the role of the intertropical discontinuity and the Darfur mountains in injecting the aerosols from Bodélé and Sudan, respectively, over the monsoon flow, and in the African easterly jet (AEJ) region. It also illustrates the impact of the daily variability of the emissions in the source regions on the dust load advected westward by the AEJ and observed over Benin. The impact of a mesoscale convective system (MCS) on the dust load and vertical distribution observed over Benin and southern Niger was also investigated, nearly 12 hours after its passage over Benin. The only discernible impact on the dust distribution is observed to be associated with widespread subsidence in the wake of the MCS, over northern Benin and Niger. Wet scavenging related to convective or stratiform rain could not be observed, as processed air masses were replaced by fresh dust transported in the upper Saharan air layer by the AEJ. Over southern Benin, the dust distribution appeared to be mostly controlled by processes affecting the planetary boundary layer upstream, i.e. over Nigeria or Chad. Because springtime dust from remote eastern sources (such as observed in this case) is mainly transported into the AEJ, it could impact on the radiation budget in the AEJ region, thereby possibly modifying the West African weather at the synoptic scale. Copyright © 2009 Royal Meteorological Society
Comment on ‘Can multi‐model combination really enhance the prediction skill of probabilistic ensemble forecasts?’
Authors: Weigel A. P. , Bowler N. E.
Published: February 2009

This note refers to the study of Weigel et al. (2008), where the success of multi‐model ensemble combination has been evaluated with a Gaussian stochastic toy model. The authors concluded that multi‐models can outperform the best participating single models, but only if the single model ensembles are under‐dispersive. Here we introduce two improved versions of the toy model of Weigel et al. For one of these models the combination of well‐dispersed (i.e. reliable) forecasts can improve the prediction skill, but for the other model this possibility is excluded. It is argued that, for normally distributed variables, the first model may be applicable in the context of short‐ and medium‐range forecasting, but the latter may be more appropriate to seasonal forecasting. Copyright © Royal Meteorological Society and Crown Copyright, 2009.
Radiative transfer validation study from the European Aqua Thermodynamic Experiment
Authors: Newman Stuart M. , Knuteson Robert. O. , Zhou Daniel K. , Larar Allen. M. , Smith William L. , Taylor Jonathan P.
Published: February 2009

The European AQUA Thermodynamic Experiment (EAQUATE) brought together collocated hyperspectral measurements from the Atmospheric Infrared Sounder (AIRS) on NASA's Aqua satellite, as well as three airborne interferometers operating in the troposphere and stratosphere. Simultaneous observations of temperature, water vapour and trace gases have been used to constrain the atmospheric state, for validation of radiometric accuracy and radiative transfer modelling. The close agreement of observations with model spectra, in the 800–1200 cm−1 region, indicates that the accuracy of modelling AIRS spectra is sufficient for beneficial use of the data in operational weather forecasting. The variability of atmospheric water vapour was found to be a fundamental constraint in the modelling of the 1400–1600 cm−1 region, emphasising the requirement for a high density of observations in future validation campaigns. Copyright © Royal Meteorological Society and Crown Copyright, 2009.
Direct intramolecular gas‐phase transfer reactions during fragmentation of sildenafil and thiosildenafil analogs in electrospray ionization mass spectrometry
Authors: Reepmeyer John C.
Published: February 2009

A study is made of the mass spectral fragmentation pathways of sildenafil, thiosildenafil, and analogous compounds. A prominent gas‐phase reaction that occurs during collision‐induced dissociation (CID) of thiosildenafil compounds is the transfer of an alkyl group from the piperazine nitrogen atom to the sulfur atom of the thiocarbonyl group. This phenomenon is clearly demonstrated through a comparison of electrospray ionization mass spectral fragmentation patterns of four sildenafil‐type compounds and three related thiosildenafil derivatives. Molecular modeling and fragmentation patterns support a direct intramolecular alkyl transfer mechanism rather than an ion‐neutral complex mechanism. CID of thiohydroxyhomosildenafil results in a facile hydroxyethyl migration to the sulfur atom followed by a second intramolecular reaction to form a spiro‐1,3‐oxathiolane ring, which fragments in two directions to generate both carbonyl and thiocarbonyl product ions from this thiocarbonyl compound. While methyl migration to the thiocarbonyl sulfur atom of thiosildenafil is dominant, methyl migration to the carbonyl oxygen atom of sildenafil may occur to a small extent. Published in 2008 by John Wiley & Sons, Ltd.
Electrochemical properties of niosomes‐modified Au electrode and its interaction with 1‐anilino‐8‐naphthalene‐sulfonate
Authors: Yang Chang‐Ying , Dai Zhong‐Xu , Li Xin , Rong Fan‐Chong
Published: February 2009

The gold electrode was modified by noisomes, prepared by sonicating the mixed solution of PEG 6000/Tween 80/Span 80/H2O. Electrochemical cyclic voltammetry (CV) and impedance spectroscopy (EIS) were performed for characterizing the modification. The construction of multilayer films of octadecanethiol (ODT)‐niosomes had almost no pinholes, which elicited that niosomes‐coated electrode through ODT assembly was more effective immobilization compared to direct modification method. A large semicircle formation in the entire range of frequency indicated the complete electron‐transfer control for the redox reaction, implying a perfect blocking behavior. The Nyquist plot was consisting of two depressed semicircles after storage for 36 h in air, which implied a progressive and uniform construction manner, as expected for porous coatings. The modified electrode was used to investigate the interaction between 1‐anilino‐8‐naphthalene‐sulfonate (ANS) and noisomes. It was found that the low‐frequency semicircular arcs increase in diameter, indicating that the increase in the resistance Rp attributed mainly to the niosomes/solution interface. It was due to the binding of ANS to the niosomes‐modified electrode surface, exhibited against diffusing species through the pores. Copyright © 2009 John Wiley & Sons, Ltd.
Focused ion beam irradiation—morphological and chemical evolution in PMMA
Authors: Kochumalayil J. J. , Meiser A. , Soldera F. , Possart W.
Published: February 2009

For poly(methyl methacrylate) (PMMA) as a representative of amorphous thermoplastic polymers, the milling effects, and the chemical changes due to ion bombardment with a focused ion beam (FIB) at normal incidence are studied with scanning force microscopy (SFM), scanning electron microscopy (SEM)/energy dispersive X‐ray (EDX), and infrared (IR) spectroscopy for varying conditions of Ga+ treatment, including the effect of partial water pressure. Stopping and Range of Ions in Matter (SRIM) simulation results for 30 keV Ga+ at normal incidence show that the zone of primary ion–polymer interaction extends ca 100 nm into the PMMA. Accordingly, this interaction region is much wider than the original beam diameter. The width of the region where the recoiled ions interact strongly with the polymer chains is larger. Secondary processes, such as fragment diffusion and phonon transport, are expected to extend even farther into the polymer. SEM and SFM reveal distinct topologies of areas milled without or in presence of water vapour. Water vapour–assisted FIB milling produces more roughness and defects. The infrared attenuated total reflection spectroscopy (IR‐ATR) spectra indicate that ion milling in PMMA damages methacrylate side groups in particular. In contrary to metals, an increase in the degree of milling is found when the beam spot overlap parameter increases. Copyright © 2009 John Wiley & Sons, Ltd.
Correcting for multivariate measurement error by regression calibration in meta‐analyses of epidemiological studies
Authors:   Fibrinogen Studies Collaboration
Published: February 2009

Within‐person variability in measured
values of multiple risk factors can bias their associations with disease. The multivariate regression calibration (RC) approach can correct for such measurement error and has been applied to studies in which true values or independent repeat measurements of the risk factors are observed on a subsample. We extend the multivariate RC techniques to a meta‐analysis framework where multiple studies provide independent repeat measurements and information on disease outcome. We consider the cases where some or all studies have repeat measurements, and compare study‐specific, averaged and empirical Bayes estimates of RC parameters. Additionally, we allow for binary covariates (e.g. smoking status) and for uncertainty and time trends in the measurement error corrections. Our methods are illustrated using a subset of individual participant data from prospective long‐term studies in the Fibrinogen Studies Collaboration to assess the relationship between usual levels of plasma fibrinogen and the risk of coronary heart disease, allowing for measurement error in plasma fibrinogen and several confounders. Copyright © 2009 John Wiley & Sons, Ltd.
Nanoparticles for Optical Molecular Imaging of Atherosclerosis
Authors: Douma Kim , Prinzen Lenneke , Slaaf Dick W. , Reutelingsperger Chris P. M. , Biessen Erik A. L. , Hackeng Tilman M. , Post Mark J. , van Zandvoort Marc A. M. J.
Published: February 2009

Molecular imaging contributes to future personalized medicine dedicated to the treatment of cardiovascular disease, the leading cause of mortality in industrialized countries. Endoscope‐compatible optical imaging techniques would offer a stand‐alone alternative and high spatial resolution validation technique to clinically accepted imaging techniques in the (intravascular) assessment of vulnerable atherosclerotic lesions, which are predisposed to initiate acute clinical events. Efficient optical visualization of molecular epitopes specific for vulnerable atherosclerotic lesions requires targeting of high‐quality optical‐contrast‐enhancing particles. In this review, we provide an overview of both current optical nanoparticles and targeting ligands for optical molecular imaging of atherosclerotic lesions and speculate on their applicability in the clinical setting.

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Coupled Ionic and Electronic Transport Model of Thin‐Film Semiconductor Memristive Behavior
Authors: Strukov Dmitri B. , Borghetti Julien L. , Williams R. Stanley
Published: February 2009

The memristor, the fourth passive circuit element, was predicted theoretically nearly 40 years ago, but we just recently demonstrated both an intentional material system and an analytical model that exhibited the properties of such a device. Here we provide a more physical model based on numerical solutions of coupled drift‐diffusion equations for electrons and ions with appropriate boundary conditions. We simulate the dynamics of a two‐terminal memristive device based on a semiconductor thin film with mobile dopants that are partially compensated by a small amount of immobile acceptors. We examine the mobile ion distributions, zero‐bias potentials, and current–voltage characteristics of the model for both steady‐state bias conditions and for dynamical switching to obtain physical insight into the transport processes responsible for memristive behavior in semiconductor films.
The neurokinin‐3 (NK3) and the neurokinin‐1 (NK1) receptors are differentially targeted to mesocortical and mesolimbic projection neurons and to neuronal nuclei in the rat ventral tegmental area
Authors: Lessard Andrée , Savard Martin , Gobeil Fernand , Pierce Joseph P. , Pickel Virginia M.
Published: February 2009

Tonic activation of neurokinin‐3 (NK3) receptors in dopamine neurons of the ventral tegmental area (VTA) has been implicated in the pathophysiology of schizophrenia. This psychiatric disorder is associated with a dysfunctional activity in VTA projection neurons that can affect cognitive function at the level of the medial prefrontal cortex (mPFC) as well as motor and motivational states controlled in part by mesolimbic output to the nucleus accumbens (Acb). To determine the relevant sites for NK3receptor activation within this neuronal network, we used confocal and electron microscopy to examine NK3receptors (Cy5; immunogold) and retrograde labeling of fluorogold (FG, FITC; immunoperoxidase) in the VTA of rats receiving either Acb or mPFC injections of FG. Comparison was made with neurokinin‐1 (NK1) receptors, which are also present, but less abundant then NK3receptors, in dopaminergic and GABAergic VTA neurons. There were no observable differences between NK3and NK1receptors in their primary locations in the cytoplasm and on the plasma membrane of VTA somata and dendrites with or without FG. Dendrites labeled with FG retrogradely transported from mPFC, however, contained more NK3or less NK1immunogold particles (plasmalemmal + cytoplasmic) then those retrogradely labeled following FG injection in the Acb. Moreover, only the NK3receptors were detected in neuronal nuclei in the VTA and in the nuclei of human HEK‐293T NK3‐transfected cells. The enrichment of NK3receptors in mesocortical projection neurons and nuclear distribution of these receptors may provide insight for understanding the selective antipsychotic effectiveness of NK3antagonists. Synapse 63:484–501, 2009. © 2009 Wiley‐Liss, Inc.
A hybrid genetic algorithm and optimality criteria method for optimum design of RC tall buildings under multi‐load cases
Authors: Li Gang , Lu Haiyan , Liu Xiang
Published: February 2009

This paper proposes a hybrid heuristic and criteria‐based method of optimum design that combines the advantages of both the genetic algorithm (GA) and the rigorously derived optimality criteria (OC) for structural optimum design of reinforced concrete tall buildings under multi‐load cases based on the current Chinese design codes. The entire optimum design procedure is divided into two parts: strength optimum design and stiffness optimum design, which are performed by the GA and the OC method, respectively. The optimum reinforcement detailing, which satisfies the strength, serviceability, ductility and other constraints related to the user‐specified rules and regulations in design codes, is achieved by constructing the data sets containing different available reinforcement bar diameter in a pre‐specified pattern. An adaptive feasible region technique is developed to improve the efficiency of GA. Finally, a practical frame‐shear‐wall structure (30‐storey) is optimized to illustrate the effectiveness and practicality of the proposed optimum design method. Copyright © 2009 John Wiley & Sons, Ltd.