bluuebunny/crossref_metadata_2025 huggingface dataset:
The new headquarters for the Lombardy Regional Government: a transparent inner court roof structure
Authors: Bassignana Mario , Bertelli Marco
Published: March 2010

The use of innovative solutions and research into lightness demands new and more complex design skills. The traditional approach to the solution of structures has been superseded by an iterative approach where all the aspects of every element designed play an important role. For the transparent inner court canopy at the Lombardy Regional Government headquarters, the project is the result of the different aspects of the building: the supporting buildings, the dimensions of the structure, the time of construction and, above all, the use of an ETFE pneumatic membrane roof covering. It is the ETFE roofing in particular that permits the design of lighter supporting frameworks. This article describes the whole building, focusing on the design steps for the transparent canopy in particular (Figs. 1 and 2).
High‐performance steels for pressure vessels
Authors: Gottlieb Joachim , Kern Andreas , Schriever Udo , Steinbeck Gregor
Published: March 2010

As consumption of energy in the world is rising, there is growing interest in the building of pressure vessels as well as apparatus engineering and equipment construction for the storage of gases or technical liquids. For these applications, like boilers, reactors and columns, unalloyed or Nb‐microalloyed steels with a minimum yield strength of up to 460 MPa have been used and produced as heavy plates according to rules and international standards and specifications (i.e. DIN EN 10028, ASTM, ASME).

The production and properties of modern steels for welded pressure vessels, which meet the actual requirements very well, are discussed here. In this respect, thanks to specific secondary metallurgy during steelmaking, targeted Nb‐microalloying, innovative rolling strategies and (if necessary) optimized heat treatment conditions, it is possible to produce a fine‐grained microstructure in order to cover the highest material property requirements, in particular toughness and resistance to brittle failure. Multiple certifications of different steel grades according to different specifications for plates made from pressure vessel steels are common practice. Additionally, important aspects regarding the processing behaviour of modern steels for pressure vessels are stress‐relief heat treatment and welding. Here, modern pressure vessel steels meet the highest demands for a practice‐oriented processing of plates.
People: Steel Construction 1/2010
Authors: Schardt Richard , Andrä Hans‐Peter , Eilzer Wolfgang , Jung Rolf , Wickbold Thomas
Published: March 2010

Minoru Yamada at 80

Holger Svensson reaches 65
Optimal Suppression of Protein Phosphatase 2A Activity Is Critical for Maintenance of Human Embryonic Stem Cell Self-Renewal
Authors: Yoon Byung Sun , Jun Eun Kyoung , Park Gyuman , Jun Yoo Seung , Moon Jai-Hee , Soon Baik Cheong , Kim Aeree , Kim Hyunggee , Kim Jong-Hoon , Young Koh Gou , Taek Lee Hoon , You Seungkwon
Published: March 2010

The self-renewal of embryonic stem cells involves a balance between processes governed by crosstalk between intrinsic and extrinsic factors. We hypothesized that protein serine/threonine phosphatase 2A (PP2A) may play a central role in the signaling pathways that regulate human embryonic stem cell (hESC) self-renewal. Biochemical analyses revealed that PP2A activity gradually increases over the course of hESC differentiation; PP2A/C and PP2A/A levels also increased. The overexpression of PP2A/C or the addition of PP2A activator C2-ceramide promoted hESC differentiation. Accordingly, the addition of PP2A inactivator okadaic acid (OA) maintained hESC self-renewal in the absence of basic fibroblast growth factor (bFGF). The hESCs maintained with OA expressed pluripotency markers and exhibited substantial telomerase activity with normal karyotypes. The hESCs were able to differentiate into derivatives of the three germ layers, both in vitro and in vivo. Furthermore, the addition of OA and bFGF enabled the maintenance of hESC self-renewal without feeder cells, even in chemically defined xeno-free media. These findings shed a light on the role of PP2A in hESC differentiation and provide a novel strategy for maintaining the self-renewal capability of hESC in bFGF-free, feeder cell-free, and xeno-free media through the optimal suppression of PP2A activity using OA.
Engineering Cell-Permeant FLP Recombinase for Tightly Controlled Inducible and Reversible Overexpression in Embryonic Stem Cells
Authors: Patsch Christoph , Peitz Michael , Otte David M. , Kesseler Daniela , Jungverdorben Johannes , Wunderlich Frank Thomas , Brüstle Oliver , Zimmer Andreas , Edenhofer Frank
Published: March 2010

Combined application of DNA recombinases Cre and FLP enables tightly controlled independent and/or sequential gene regulations. However, in practice, such dual recombinase strategies are hampered by the comparably low efficiency of the FLP recombinase. Here, we present the engineering of a recombinant cell-permeant FLP protein (TAT-FLP) that induces recombination in >75% of fibroblasts and mouse as well as human embryonic stem (ES) cells. We show that TAT-FLP ideally complements the strength of cell-permeant Cre recombinase for genetic engineering as exemplified by FLP-ON-Cre-OFF, an inducible transgene expression cassette that enables tightly controlled expression in a reversible manner. We exemplify this concept by conditional overexpression of LacZ and the caudal-related homeobox transcription factor CDX2. We expect our FLP transduction system to become widely useful for numerous genetic interventions addressing complex biological questions and the generation of transgene-free therapeutically applicable ES cell-derived cells.
Mapping of serotonin transporters by positron emission tomography with [11c]DASB in conscious common marmosets: Comparison with rhesus monkeys
Authors: Yokoyama Chihiro , Yamanaka Hajime , Onoe Kayo , Kawasaki Akihiro , Nagata Hiroko , Shirakami Keiko , Doi Hisashi , Onoe Hirotaka
Published: March 2010

The common marmoset (Callithrix jacchus) is unique among the primates in its small body size, reproductive efficacy, and characteristic social behavior, making it useful as an animal model in neuroscientific research. To assess the brain serotonergic systems, we investigated the binding of [11C]‐3‐amino‐4‐(2‐dimetylaminomethyl‐phenylsulfanyl)‐benzonitrile ([11C]DASB) to brain serotonin transporter (SERT) in conscious common marmosets using positron emission tomography (PET), and compared with findings for rhesus monkeys. Both species showed globally similar distribution patterns of [11C]DASB uptake in the brain, with highest activity in the midline of the brain and lowest in the cerebellum, and higher activity in some subcortical regions than in surrounding cortex, while the common marmoset brain showed almost equal or rather higher binding potential (BP) values (BPND) in cortical regions and hippocampus, and lower BPND than the rhesus monkey brain in some subcortical regions. Test‐retest reproducibility of BPND at an interval of several months was high, indicating reliable and stable measurements of serotonin transporters in both species. These results suggest that SERT imaging by PET with [11C]DASB under conscious state is valuable for investigating the physiological serotonergic functions in common marmosets (182). Synapse 2010. © 2010 Wiley‐Liss, Inc.
Hippocampal epigenetic modification at the doublecortin gene is involved in the impairment of neurogenesis with aging
Authors: Kuzumaki Naoko , Ikegami Daigo , Tamura Rie , Sasaki Takuya , Niikura Keiichi , Narita Michiko , Miyashita Kazuhiko , Imai Satoshi , Takeshima Hideyuki , Ando Takayuki , Igarashi Katsuhide , Kanno Jun , Ushijima Toshikazu , Suzuki Tsutomu , Narita Minoru
Published: March 2010

Recent research has suggested that epigenetic mechanisms, which exert lasting control over gene expression without altering the genetic code, could mediate stable changes in brain function. A growing body of evidence supports the idea that epigenetic changes play a role in the etiology of aging and its associated brain dysfunction. The present study was undertaken to evaluate the age‐related changes in the expression of doublecortin, which is a marker for neuronal precursors, along with epigenetic modification in the hippocampus of aged mice. In the present study, the doublecortin‐positive cells were almost completely absent from the dentate gyrus of the hippocampus of 28‐month‐old mice. Furthermore, the expression level of doublecortin mRNA was significantly decreased in the hippocampus of aged mice. Under these conditions, a significant decrease in H3K4 trimethylation and a significant increase in H3K27 trimethylation at doublecortin promoters were observed with aging without any changes in the expression of their associated histone methylases and demethylases in the hippocampus. These findings suggest that aging produces a dramatic decrease in the expression of doublecortin along with epigenetic modifications in the hippocampus. Synapse 2010. © 2010 Wiley‐Liss, Inc.
Effects of repeated electroconvulsive seizure on cell proliferation in the rat hippocampus
Authors: Ito Masanobu , Seki Tatsunori , Liu Juan , Nakamura Kyoko , Namba Takashi , Matsubara Yoichiro , Suzuki Toshihito , Arai Heii
Published: March 2010

Electroconvulsive therapy (ECT) is known as a successful treatment for severe depression. Despite great efforts, the biological mechanisms underlying the beneficial effects of ECT remain largely unclear. In this study, animals received a single, 10, or 20 applications of electroconvulsive seizure (ECS), and then cell proliferation and apoptosis were investigated in the subgranular zone (SGZ) of the dentate gyrus. We analyzed whether a series of ECSs could induce changes in the dentate gyrus in a dose‐response fashion. A single‐ECS seizure significantly increased cell proliferation in the SGZ by ∼2.3‐fold compared to sham treatment. After 10 ECSs, a significant increase in cell proliferation was observed in the SGZ by ∼2.4‐fold compared to sham treatment. Moreover, 10 ECSs induced a significant increase in cell proliferation by 1.3‐fold compared to a single‐ECS group. However, cell proliferation did not differ between the group with 20 ECSs and sham group. In addition, a significant increase in the number of apoptotic cells was found in the group with 10 ECSs, whereas no significant change in it was found in either a single ECS or 20 ECSs group compared to sham treatment. These findings indicate that the optimal number of treatments and duration of stimulation requires investigation. Further studies are needed to elucidate the intracellular mechanisms underlying both effective and excessive ECT. Synapse 64:814–821, 2010. © 2010 Wiley‐Liss, Inc.
Bioactive secondary metabolites from symbiotic marine dinoflagellates: symbiodinolide and durinskiols
Authors: Kita Masaki , Ohno Osamu , Han Chunguang , Uemura Daisuke
Published: March 2010

Symbiotic relationships play critical roles in marine ecosystems. Among symbionts, marine dinoflagellates have attracted the attention of natural products chemists, biologists, and ecologists, since they are rich sources of unique bioactive secondary metabolites. The polyol compound symbiodinolide, which was isolated from the symbiotic dinoflagellate Symbiodinium sp., exhibits significant voltage‐dependent N‐type Ca2+ channel‐opening activity and may serve as a defense substance to prevent digestion of the host animals. Durinskiols are also unique long carbon‐chain polyol compounds that were isolated from the dinoflagellate Durinskia sp. We found a selective cleavage reaction of allylic 1,2‐diol using an olefin metathesis catalyst, and developed a fluorescent‐labeling method for MS/MS analysis to achieve the structural elucidation of huge polyol compounds. This review highlights recent advances in structural and biological studies on symbiodinolide, durinskiols, and related polyol compounds. © 2010 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 10: 57–69; 2010: Published online in Wiley InterScience (www.interscience.wiley.com) DOI 10.1002/tcr.200900007
Linear diversity precoding design criterion for finite block‐fading parallel MIMO channels
Authors: Sykora Jan , Knize Milan
Published: March 2010

A novel optimal two stage coding for finite set of parallel flat‐fading MIMO channels with single common information source with specific constant rate requirement is derived. The optimality of suggested coding is achieved in terms of the capacity versus outage performance. The well‐known optimal coding rule relies on Gaussian codewords spanned over the whole available finite set of parallel channels. We prove that the equivalent preprocessing to the ideal interleaving is to re‐code independent parallel channels codewords by a linear inner precoder from a special class of unitary precoders complying with the optimality criterion derived in the paper. Performing such linear mixture of codewords sharing common Gaussian block‐wise codebook, the same capacity versus the outage is guaranteed without any interleaving over parallel channels. We utilize a virtual multiple access (VMA) channel approach to derive the optimality criterion. Selected precoders with various space‐time or time‐only domain span were tested against this criterion and we provide the optimality results on variety of the channel parameters. We showed that the temporal processing is the most important one to achieve the optimality of the precoder. A full space‐time precoding does not perform better than one which is temporal‐only. Copyright © 2010 John Wiley & Sons, Ltd.
Unsteady two‐dimensional potential‐flow model for thin variable geometry airfoils
Authors: Gaunaa Mac
Published: March 2010

In the present work, analytical expressions for distributed and integral unsteady two‐dimensional forces on a variable geometry airfoil undergoing arbitrary motion are derived under the assumption of incompressible, irrotational, inviscid flow. The airfoil is represented by its camber line as in classic thin‐airfoil theory, and the deflection of the airfoil is given by superposition of chord‐wise deflection mode shapes. It is shown from the expressions for the forces that the influence from the shed vorticity in the wake is described by the same time lag for all chord‐wise positions on the airfoil. This time‐lag term can be approximated using an indicial function approach, making the practical calculation of the aerodynamic response numerically very efficient by use of Duhamel superposition. Furthermore, the indicial function expressions for the time‐lag terms are formulated in their equivalent state‐space form, allowing for use of the present theory in problems employing the eigenvalue approach, such as stability analysis.

The analytical expressions for the integral forces can be reduced to Munk's steady and Theodorsen's unsteady results for thin airfoils, and numerical evaluation shows excellent agreement with other unsteady two‐dimensional thin‐airfoil results.

Apart from the obvious applications within active load control/reduction, the present theory can be used for various applications which up to the formulation of the present theory have been possible only using much more computational costly methods. An example that highlights this feature is the propulsive performance of a soft heaving propulsor presented in this paper. Copyright © 2010 John Wiley & Sons, Ltd.
Formation of an Acyl‐Ethynyl‐Methylidyne Complex of Cobalt: Structure of Co3{μ3‐CC(O)C≡C[Ru(dppe)Cp*]}(CO)8(PPh3)
Authors: Bruce Michael I. , Zaitseva Natasha N. , Skelton Brian W. , White Allan H.
Published: March 2010

The reaction between Ru(C≡CH)(dppe)Cp* and Co3(μ3‐CBr)(CO)9 in the presence of Pd(PPh3)4/CuI afforded dark red Co3{μ3‐CC(O)C≡C[Ru(dppe)Cp*]}(CO)8(PPh3), whose formation may involve attack of the Ru‐ethynyl fragment on an intermediate cluster‐bound CCO ligand; abstraction of PPh3 from the palladium catalyst also occurs.
Synthesis, Characterization and Fluorescent Properties of Three One‐Dimensional Coordination Polymers Derived from Polypyridyl Ligands
Authors: Heine Johanna , Westemeier Hauke , Dehnen Stefanie
Published: March 2010

Three one‐dimensional coordination polymers, [MnCl2(4‐pyterpy)]∙2CHCl3 (1), [Mn(NO3)2(4‐pyterpy)]∙CHCl3 (2) and [Ag(NO3)(3‐pyterpy)]∙H2O (3) (4‐pyterpy = 4′‐(4‐pyridyl)‐2,2′:6′,2″‐terpyridine and 3‐pyterpy = 4′‐(3‐pyridyl)‐2,2′:6′,2″‐terpyridine) were synthesized and characterized by X‐ray diffraction. All three compounds exhibit a rare “head‐to‐tail” coordination of the multidentate ligand, but differ significantly in their polymer chain conformations. Additionally, the fluorescent properties of all three compounds were investigated and show a weak, ligand‐centered fluorescence at 416–418 nm.
The importance of forest patch networks for the conservation of the Thorn‐tailed Rayaditos in central Chile
Authors: Vergara Pablo M. , Hahn Ingo J. , Zeballos Horacio , Armesto Juan J.
Published: March 2010

Conservation of forest birds in fragmented landscapes requires not only determining the critical patch characteristics influencing local population persistence but also identifying patch networks providing connectivity and suitable habitat conditions necessary to ensure regional persistence. In this study, we assessed the importance of patch attributes, patch connectivity, and network components (i.e., groups of interconnected patches) in explaining the occupancy pattern of the Thorn‐tailed Rayadito (Aphrastura spinicauda), a forest bird species of central Chile. Using a daily movement threshold distance, we identified a total of 16 network components of sclerophyllous forest within the study area. Among those components, patch area and vegetation structure‐composition were important predictors of patch occupancy. However, the inclusion of patch connectivity and component size (i.e., the area of a network component) into the models greatly increases the models’ accuracy and parsimony. Using the best‐fitted model, a total of 33 patches were predicted to be occupied by rayaditos within the study area, but such occupied patches were distributed in only six network components. These results suggest that persistence of rayaditos in central Chile requires the maintenance of large single patches and patch networks providing habitat and connectivity.
Overview of the physiological changes and optimal diet in the golden age generation over 50
Authors: Gille Doreen
Published: March 2010

Basically, our lifespan is determined genetically. However, several other parameters such as the environment, lifestyle and diet have a high impact on living in the best of health. Many older persons suffer from various diseases, which often cannot be avoided; however, their development can be postponed and symptoms can be mitigated by a balanced diet, moderate physical activity as well as a healthy lifestyle. These diseases are, for example, sarcopenia (degenerative loss of muscle mass), osteoporosis (decomposition of bone structure), digestive restrictions, sensory impairment, water imbalance or a compromised immune system. Psychological modifications, obesity and loss of weight also commonly occur in older adults. To define an adequate diet for elderly between the ages 50 and 80 is difficult, even impossible, because the nutritional requirements differ between the dynamic quinquagenarian and the frailer eighty-year-old. However, several studies have shown that sufficient consumption of high-quality proteins, calcium, vitamin D, anti-oxidative food compounds, water as well as adapted energy values and nourishment with high-nutrient density in combination with physical activity especially help one to remain healthy to a great age. The cornerstone of healthy ageing is the maintenance of normal bodyweight in order to prevent the development of diseases such as osteoporosis, coronary heart disease or diabetes type 2. This publication will review the physiological changes that occur with advanced age and consequential nutritional recommendations for elderly persons.
Brief report: The number of sexual partners and race‐related stress in African American adolescents: Preliminary findings
Authors: Stevens‐Watkins Danelle , Brown‐Wright Lynda , Tyler Kenneth
Published: March 2010

The current study examined the association between the number of lifetime sexual partners and race‐related stress among African American 201 high school juniors and seniors at two urban high schools in the Southeastern region of the country. Students completed the Index of Race‐Related Stress‐Brief (IRRS‐B) and the Youth Risk Behavior Survey (YRBS). African American male adolescents reported higher race‐related stress and a higher number of sexual partners compared to African American females. Controlling for gender and age of first intercourse, race‐related stress significantly predicted the number of sexual partners for African American adolescents. Preliminary findings indicate that the role of race‐related stress may prove critical in decreasing risky sexual behavior among African American adolescents.
Acoustic recordings in human ear canals to sounds at different locations
Authors: Kuwada Clinton A. , Bishop Brian , Kuwada Shigeyuki , Kim Duck O.
Published: March 2010

The head and pinna shape the sound reaching the tympanum. We explored this signal transformation in humans and a mini basketball for different sound locations in an anechoic chamber. For humans, we embedded microphones in ear molds that were custom fitted to the subject's ear canal. For the ball, the microphones were flush with the surface at ± 90 degrees azimuths on the equator. Sounds were generated with a custom point source. In the ball, the signal level was nearly flat across frequency, with no gains. In contrast, in the ears, signal level changed in a complex way across frequency, with considerable gains. For frequencies < 2 kHz, the interaural level difference (ILD) increased with decreasing distance similarly in the human ears and ball. For frequencies > 4 kHz, ILDs in the human ears were larger and more complex than those in the ball such that the human ILDs were nonmonotonic with distance whereas the ball ILDs were monotonic with distance.
TriVerse versus molecular resonance–harvested grafts in single‐stage Baha surgery
Authors: D'Eredita Riccardo , Cenzi Mario
Published: March 2010

Objectives

To assess complications occurring in patients with a bone‐anchored cochlear stimulator (Baha) following split‐thickness skin graft harvested with two surgical modalities: the TriVerse (TV) system and the molecular resonance generator (MR).

Study Design

Prospective, randomized, two‐group (TV and MR) study of 24 patients who underwent Baha surgery.

Setting

Tertiary care institution.

Subjects and Methods

All patients (5 children, age range 6‐14 yrs, median 8.3 yrs, and 16 adults, age range 30‐73 yrs, median 60 yrs) underwent the one‐stage procedure. The skin flap was harvested by use of the TV in 12 cases (2 children, 10 adults) and the MR generator in 12 (3 children, 9 adults). The main outcome measures were wound healing time, number of follow‐up visits, degree of soft tissue reactions around the abutment, and need for revision surgery were examined.

Results

There was a clear difference between the TV‐ and MR‐harvested skin graft groups in relation to severity of skin reactions and complete healing time. The TV group required from three to seven (median 4) visits as outpatients during the initial observation period until healing was complete. The MR group required only one to three (median 2) visits. Complete healing time was significantly lower in the MR group (range 7‐12 days, median 10 days) compared to the TV group (range 15‐28 days, median 16 days). In the TV group, two patients required in‐office revision of the skin graft because of partial necrosis.

Conclusions

In our experience, the MR‐harvested split‐thickness skin graft is superior to the TV technique.
Screening for obstructive sleep apnea/hypopnea syndrome: Subjective and objective factors
Authors: Friedman Michael , Wilson Meghan N. , Pulver Tanya , Pandya Hemang , Joseph Ninos J. , Lin Hsin‐Ching , Chang Hsueh‐Wen
Published: March 2010

Objectives

To determine the sensitivity and specificity of the Berlin Questionnaire and the Obstructive Sleep Apnea/Hypopnea Syndrome (OSAHS) score for individually predicting a diagnosis of OSAHS, and to propose a method for OSAHS screening incorporating objective and subjective factors.

Study Design

Cross‐sectional survey.

Setting

Tertiary care center.

Methods

Charts were reviewed from 223 consecutive patients for whom complete data regarding the Berlin questionnaire, OSAHS score (Friedman tongue position + tonsil size + body mass index grade), Epworth Sleepiness Scale, and visual analog scale for snoring were obtained prior to polysomnography (PSG). Sensitivity and specificity were determined for the Berlin questionnaire and OSAHS score for predicting an apnea hypopnea index (AHI) ≥ 5. Patient data were subjected to multivariate stepwise discriminant analysis and used to construct a screening system based on the Fisher's linear classification equation. Results were cross‐validated by PSG findings.

Results

In predicting an AHI ≥ 5, the sensitivity and specificity, respectively, were 0.615 and 0.226 for the Berlin questionnaire, 0.863 and 0.468 for OSAHS score, and 0.82 and 0.834 for our predictive equation. When applied case‐wise to the study population, this equation correctly predicted 82.5 percent of diagnoses. Accuracy was highest for severe OSAHS (87.4%) and lowest for mild disease (77.0%). Sensitivity was lowest for mild OSAHS (0.50).

Conclusions

Neither the Berlin questionnaire nor the OSAHS score alone was both highly sensitive and specific for diagnosing OSAHS. By incorporating subjective and objective metrics into a single predictive equation, sensitivity and specificity were maximized, and 82.5 percent of diagnoses were accurately predicted.
Reliability of airway obstruction analyses from Sleep MRI sequences
Authors: Barrera Jose E. , Chang Ray C. , Popelka Gerald R. , Holbrook Andrew B.
Published: March 2010

Objective

A real‐time MRI “movie” during natural sleep (“Sleep MRI”) allows observation of dynamic airway obstructions in obstructive sleep apnea syndrome (OSAS) patients. The purpose of this article was to determine the reliability of assessing these obstructions.

Study Design

Cross‐sectional diagnostic test evaluation.

Setting

Academic referral center.

Subjects and Methods

A total of 23 Sleep MRI sequences randomly selected from 20 consecutive OSAS patients were analyzed by two experienced sleep surgeons on two separate occasions separated by at least two weeks. Five dimensions were assessed: presence or absence of any obstruction, presence or absence of a retropalatal obstruction, presence or absence of a retroglossal obstruction, presence or absence of a swallow, and duration of an obstructive event.

Results

For all dimensions measured, intra‐rater reliability coefficients ranged from a low of 0.95 to a high of 1.0 for each rater. Inter‐rater reliability coefficients ranged from a low of 0.85 to a high of 1.0. On two separate evaluations separated by at least two weeks, rater 1 identified a retropalatal obstruction in 100 percent of sequences, whereas rater 2 did so in 91 percent and 96 percent of the sequences, respectively. Retroglossal obstruction was identified in 57 percent (rater 1) and 65 percent (rater 2) of sequences.

Conclusion

Intra‐rater and inter‐rater reliability coefficients are very high for determination of presence or absence of any obstruction, presence or absence of a retropalatal obstruction, presence or absence of a retroglossal obstruction, presence or absence of a swallow, and duration of obstruction from Sleep MRI sequences in OSAS patients.
Postoperative management following sphincter pharyngoplasty
Authors: Kilpatrick Lauren A. , Kline Richard M. , Hufnagle Kathryn E. , Vanlue Michael J. , White David R.
Published: March 2010

Objective

To evaluate postoperative airway‐associated outcomes following sphincter pharyngoplasty.

Study Design

Case series with chart review.

Setting

Academic tertiary care medical center.

Subjects and Methods

Postoperative management of sphincter pharyngoplasty (SP) conventionally includes overnight observation to monitor for upper airway obstruction. To evaluate for postoperative airway‐related outcomes, 36 patients who underwent SP between April 2003 and January 2009 were evaluated retrospectively.

Results

Mean patient age was 8.1 (SD 4.3) years. Mean follow‐up was 6.5 (SD 10.7) months. Cleft palate (36.1%), velo‐cardio‐facial syndrome (22.2%), and post‐adenoidectomy (16.7%) were the most common causes of velopharyngeal insufficiency. All patients underwent overnight observation postoperatively. Mean hospital stay was 1.2 (SD 0.5) days. Five patients remained inpatient two or three days owing to fever (2 patients), bleeding ear after concurrent otoplasty (1 patient), minimal oropharyngeal bleeding with spontaneous resolution (1 patient), and medication allergy (1 patient). No patient had a documented apneic event or desaturation below 95 percent. Although no desaturations were documented, four patients received supplemental oxygen: three for less than two hours, and one for 12 hours. All patients had adequate oral intake and pain control on oral medications prior to discharge; nine patients required one to three doses of intravenous narcotic medication for pain on postoperative day zero.

Conclusion

Upper airway obstruction requiring overnight observation following SP is uncommon. In otherwise healthy patients, performing SP in an outpatient setting, given appropriate recovery room evaluation for airway concerns, oral intake, and pain control, should be considered.
The influence of maternal glycaemia and dietary glycaemic index on pregnancy outcome in healthy mothers
Authors: McGowan Ciara A. , McAuliffe Fionnuala M.
Published: March 2010

Infant birth weight has increased in Ireland in recent years along with levels of childhood overweight and obesity. The present article reviews the current literature on maternal glycaemia and the role of the dietary glycaemic index (GI) and its impact on pregnancy outcomes. It is known that maternal weight and weight gain significantly influence infant birth weight. Fetal macrosomia (birth weight >4000 g) is associated with an increased risk of perinatal trauma to both mother and infant. Furthermore, macrosomic infants have greater risk of being obese in childhood, adolescence and adulthood compared to normal-sized infants. There is evidence that there is a direct relationship between maternal blood glucose levels during pregnancy and fetal growth and size at birth, even when maternal blood glucose levels are within their normal range. Thus, maintaining blood glucose concentrations within normal parameters during pregnancy may reduce the incidence of fetal macrosomia. Maternal diet, and particularly its carbohydrate (CHO) type and content, influences maternal blood glucose concentrations. However, different CHO foods produce different glycaemic responses. The GI was conceived by Jenkins in 1981 as a method for assessing the glycaemic responses of different CHO. Data from clinical studies in healthy pregnant women have documented that consuming a low-GI diet during pregnancy reduces peaks in postprandial glucose levels and normalises infant birth weight. Pregnancy is a physiological condition where the GI may be of particular relevance as glucose is the primary fuel for fetal growth.
Short-pulse laser ablation of materials at high intensities: Influence of plasma effects
Authors: Batani Dimitri
Published: March 2010

The paper is devoted to the study of plasma effects, which are present in laser ablation at relatively high intensity (I ≥ 1012 W/cm2). We start from the classical “two temperature model” of laser ablation (“cold solid approximation”) and we extend it to higher intensities where laser-induced heating and laser-induced changes in the background material become relevant. The new model is also compared to experimental results on laser ablation of solid targets from short pulse lasers at high intensities (up to 1014 W/cm2). Finally, we consider the effects on laser-ablation of laser-generated fast electrons.
Wakefield effects on the evolution of symmetric laser pulses in a plasma channel
Authors: Jha Pallavi , Malviya Amita , Upadhyay Ajay K.
Published: March 2010

The present study deals with the propagation of short laser pulses in a parabolic plasma channel. A variational technique is used to obtain simultaneous evolution equations describing the laser pulse length and spot size in the presence of relativistic and ponderomotive nonlinearities. The effect of wakefields (inside the pulse) on the propagation characteristics of the laser beam is studied. Numerical methods are used to graphically analyze the evolution of the laser pulse length and intensity.
Formal analysis of design process dynamics
Authors: Bosse Tibor , Jonker Catholijn M. , Treur Jan
Published: March 2010

This paper presents a formal analysis of design process dynamics. Such a formal analysis is a prerequisite to come to a formal theory of design and for the development of automated support for the dynamics of design processes. The analysis was geared toward the identification of dynamic design properties at different levels of aggregation. This approach is specifically suitable for component-based design processes. A complicating factor for supporting the design process is that not only the generic properties of design must be specified, but also the language chosen should be rich enough to allow specification of complex properties of the system under design. This requires a language rich enough to operate at these different levels. The Temporal Trace Language used in this paper is suitable for that. The paper shows that the analysis at the level of a design process as a whole and at subprocesses thereof is precise enough to allow for automatic simulation. Simulation allows the modeler to manipulate the specifications of the system under design to better understand the interlevel relationships in his design. The approach is illustrated by an example.
Chemical erosion rates of river basins of the Ganga system in the Himalaya: Reanalysis based on inversion of dissolved major ions, Sr, and 87Sr/86Sr
Authors: Tripathy Gyana Ranjan , Singh Sunil Kumar
Published: March 2010

Available data on chemical and Sr isotopic composition of the headwaters of the Ganga and its tributaries in the Himalaya are analyzed using inverse and the forward models to quantify the silicate and carbonate erosion rates in their basins and to parameterize the controlling factors of contemporary chemical erosion. The estimates of silicate‐derived cations based on the inverse model are lower on average by ∼20% than that derived from the forward model, a result attributable to differences in the release ratios of major ions between the two models. The inverse model yields the best fit values for the release ratio of various major ions based on measured river chemistry and therefore is more likely to be representative of the basins, unlike the forward model, in which the release ratios are assumed. Among the various tributaries, the Kosi and the Bhagirathi have relatively larger contributions from silicate weathering to the cation budget with high 87Sr/86Sr, consistent with the lithologies of their basins, which are dominated by silicates. The Ganga river system in the Himalaya is known to be supersaturated with respect to calcite during lean flow periods. The inverse model calculates the extent of Ca loss to be between ∼10%–40% with the highest for the Gandak. The silicate and carbonate erosion rates for these Himalayan rivers are relatively higher, in the ranges of 9.9–17.6 and 12.4–92.3 tons/km2/yr, respectively, compared to other global rivers. The higher chemical erosion rates in these river basins could be due to intense physical erosion caused by their higher relief and runoff.
Processes influencing seasonal hypoxia in the northern California Current System
Authors: Connolly T. P. , Hickey B. M. , Geier S. L. , Cochlan W. P.
Published: March 2010

This paper delineates the role of physical and biological processes contributing to hypoxia, dissolved oxygen (DO) < 1.4 mL/L, over the continental shelf of Washington State in the northern portion of the California Current System. In the historical record (1950–1986), during the summer upwelling season, hypoxia is more prevalent and severe off Washington than further south off northern Oregon. Recent data (2003–2005) show that hypoxia over the Washington shelf occurred at levels previously observed in the historical data. The year 2006 was an exception, with hypoxia covering ∼5000 km2 of the Washington continental shelf and DO concentrations below 0.5 mL/L at the inner shelf, lower than any known previous observations at that location. In the 4 years studied, upwelling of low DO water and changes in source water contribute to interannual variability, but cannot account for seasonal decreases below hypoxic concentrations. Deficits of DO along salinity surfaces, indicating biochemical consumption of DO, vary significantly between surveys, accounting for additional decreases of 0.5–2.5 mL/L by late summer. DO consumption is associated with denitrification, an indicator of biochemical sediment processes. Mass balances of DO and nitrate show that biochemical processes in the water column and sediments each contribute ∼50% to the total consumption of DO in near‐bottom water. At shorter than seasonal time scales on the inner shelf, along‐shelf advection of hypoxic patches and cross‐shelf advection of seasonal gradients are both shown to be important, changing DO concentrations by 1.5 mL/L or more over 5 days.
Langerin functions as an antiviral receptor on Langerhans cells
Authors: van der Vlist Michiel , Geijtenbeek Teunis B H
Published: March 2010

Langerhans cells (LC) are the first dendritic cells (DC) to encounter pathogens entering the body via mucosa or skin. Equipped with pattern recognition receptors (PRR), LC are able to detect and respond to these pathogens. An important PRR, in human exclusively expressed by LC, is the C‐type lectin Langerin. Langerin forms a protective barrier against HIV‐1 infection by binding and degradation of this virus. In addition, antigens targeted to Langerin are presented to T cells to induce an adaptive immune response. Therefore Langerin functions as an innate anti‐viral defense mechanism and an antigen receptor involved in adaptive immune responses. Here, we review the role of Langerin in antiviral protection, its structural similarity to other C‐type lectins, and how its function and polymorphisms influence the function of Langerhans cells.
Isolation of a mouse bone marrow population enriched in stem and progenitor cells by centrifugation on a Percoll gradient
Authors: Rosca Ana‐Maria , Burlacu Alexandrina
Published: March 2010

Given the complex composition of bone marrow, a cell separation technique that results in populations enriched in progenitor cells is required for cellular differentiation and transplantation studies. In the present study, we designed a method that allows for the isolation of a progenitor‐enriched population of bone marrow by exploiting the physical properties of these cells. Bone marrow aspirate was separated on a discontinuous Percoll gradient (ranging from 1.050 to 1.083 g/cm3) that resulted in the recovery of six cell fractions. The fractions were characterized by FACS and RT–PCR (reverse transcription–PCR) analyses and evaluated for their capacity to differentiate into haematopoietic and mesenchymal cells. Fraction IV, including cells with a density of 1.070–1.076 g/ml, contained 11.68% of total bone marrow cells and was enriched in c‐kit+ and Sca‐1+ (stem cell antigen‐1) progenitor cells as compared with total bone marrow. This fraction demonstrated an increase in clonogenic capacity under specific conditions as well as a potential to generate a mesenchymal stem cell culture in a shorter period than that using bone marrow aspirate. Furthermore, this fraction lacked differentiated cell types and contained cells positive for endothelial markers, which further increases its value in cellular transplant. In conclusion, a bone marrow subpopulation that is enriched in progenitor cells and may be valuable in cellular transplant therapy can be isolated by exploiting the physical properties of these cells.
Regulation of the miR-212/132 locus by MSK1 and CREB in response to neurotrophins
Authors: Remenyi Judit , Hunter Christopher J. , Cole Christian , Ando Hideaki , Impey Soren , Monk Claire E. , Martin Kirsty J. , Barton Geoffrey J. , Hutvagner Gyorgy , Arthur J. Simon C.
Published: March 2010

Neurotrophins are growth factors that are important in neuronal development and survival as well as synapse formation and plasticity. Many of the effects of neurotrophins are mediated by changes in protein expression as a result of altered transcription or translation. To determine whether neurotrophins regulate the production of microRNAs (miRNAs), small RNA species that modulate protein translation or mRNA stability, we used deep sequencing to identify BDNF (brain-derived neurotrophic factor)-induced miRNAs in cultured primary cortical mouse neurons. This revealed that the miR-212/132 cluster contained the miRNAs most responsive to BDNF treatment. This cluster was found to produce four miRNAs: miR-132, miR-132*, miR-212 and miR-212*. Using specific inhibitors, mouse models and promoter analysis we have shown that the regulation of the transcription of the miR-212/132 miRNA cluster and the miRNAs derived from it are regulated by the ERK1/2 (extracellular-signalregulated kinase 1/2) pathway, via both MSK (mitogen and stress-activated kinase)-dependent and -independent mechanisms.
Iron-binding activity of human iron–sulfur cluster assembly protein hIscA1
Authors: Lu Jianxin , Bitoun Jacob P. , Tan Guoqiang , Wang Wu , Min Wenguang , Ding Huangen
Published: March 2010

A human homologue of the iron–sulfur cluster assembly protein IscA (hIscA1) has been cloned and expressed in Escherichia coli cells. The UV–visible absorption and EPR (electron paramagnetic resonance) measurements reveal that hIscA1 purified from E. coli cells contains a mononuclear iron centre and that the iron binding in hIscA1 expressed in E. coli cells can be further modulated by the iron content in the cell growth medium. Additional studies show that purified hIscA1 binds iron with an iron association constant of approx. 2×1019 M−1, and that the iron-bound hIscA1 is able to provide the iron for the iron–sulfur cluster assembly in a proposed scaffold protein, IscU of E. coli, in vitro. The complementation experiments indicate that hIscA1 can partially substitute for IscA in restoring the cell growth of E. coli in the M9 minimal medium under aerobic conditions. The results suggest that hIscA1, like E. coli IscA, is an iron-binding protein that may act as an iron chaperone for biogenesis of iron–sulfur clusters.
A novel water resistor divider with a coaxial low-voltage arm
Authors: Jia Wei , Chen Weiqing , Mao Congguang , Zeng Jiangtao
Published: March 2010

A new style high voltage resistor divider made of saline solution has been constructed and tested. A coaxial construction is used on the low-voltage arm, as the signal extraction electrode, which can increase the attenuation ratio of the divider. The time response of divider limited by the stray parameter also can be improved. Comparing the results of calibrated experiment with the commonly used equal size copper sulfate dividers, the new probe has nearly five times increase in the attenuation ratio. The time response of the new style divider in the dimension of 30 mm in diameter and 400 mm in length can reach to 1 ns.
Ultrashort high quality electron beam from laser wakefield accelerator using two-step plasma density profile
Authors: Zhu Xiongwei
Published: March 2010

In this paper, we first use the rf linac injector mechanism to generate ultrashort high quality electron beam from laser wakefield accelerator (LWFA) with two-step plasma density profile successfully. We incorporate the physics principle in the conventional rf linac injector into the LWFA by using two-step plasma density to decrease the wavelength of the wakefield in plasma. Using this mechanism, we observe a ultrashort high quality electron beam (the rms energy spread is 1.9%, and the rms bunch length is 2 fs) in the simulation. The ultrashort intense terahertz coherent radiation (200 MW, 2 fs) can be generated with the proposed laser wakefield accelerator.
Dressed counterions: Strong electrostatic coupling in the presence of salt
Authors: Kanduč Matej , Naji Ali , Forsman Jan , Podgornik Rudolf
Published: March 2010

We reformulate the theory of strong electrostatic coupling in order to describe an asymmetric electrolyte solution of monovalent salt ions and polyvalent counterions using field-theoretical techniques and Monte Carlo simulations. The theory is based on an asymmetric treatment of the different components of the electrolyte solution. The weak coupling Debye–Hückel approach is used in order to describe the monovalent salt ions while a strong coupling approach is used to tackle the polyvalent counterions. This combined weak-strong coupling approach effectively leads to dressed interactions between polyvalent counterions and thus directly affects the correlation attraction mediated by polyvalent counterions between like-charged objects. The general theory is specifically applied to a system composed of two uniformly charged plane-parallel surfaces in the presence of salt and polyvalent counterions. In the strong coupling limit for polyvalent counterions, the comparison with Monte Carlo simulations shows good agreement for large enough values of the electrostatic coupling parameter. We delineate two limiting laws that in fact encompass all the Monte Carlo data.
Conversion of neutral nitrogen-vacancy centers to negatively charged nitrogen-vacancy centers through selective oxidation
Authors: Fu K.-M. C. , Santori C. , Barclay P. E. , Beausoleil R. G.
Published: March 2010

The conversion of neutral nitrogen-vacancy centers to negatively charged nitrogen-vacancy centers is demonstrated for centers created by ion implantation and annealing in high-purity diamond. Conversion occurs with surface exposure to an oxygen atmosphere at 465 °C. The spectral properties of the charge-converted centers are investigated. Charge state control of nitrogen-vacancy centers close to the diamond surface is an important step toward the integration of these centers into devices for quantum information and magnetic sensing applications.
Optically tuneable blue phase photonic band gaps
Authors: Liu Hu-Yi , Wang Chun-Ta , Hsu Chiao-Yun , Lin Tsung-Hsien , Liu Jui-Hsiang
Published: March 2010

This study investigates an optically switchable band gap of photonic crystal that is based on an azobenzene-doped liquid crystal blue phase. The trans-cis photoisomerization of azobenzene deforms the cubic unit cell of the blue phase and shifts the photonic band gap. The fast back-isomerization of azobenzene was induced by irradiation with different wavelengths light. The crystal structure is verified using Kossel diffraction diagram. An optically addressable blue phase display, based on Bragg reflection from the photonic band gap, is also demonstrated. The tunable ranges are around red, green, and blue wavelengths and exhibit a bright saturated color.