bluuebunny/crossref_metadata_2025 huggingface dataset:
Familial Hemiplegic Migraine CaV2.1 Channel Mutation R192Q Enhances ATP-gated P2X3 Receptor Activity of Mouse Sensory Ganglion Neurons Mediating Trigeminal Pain
Authors: Nair Asha , Simonetti Manuela , Birsa Nicol , Ferrari Michel D , van den Maagdenberg Arn MJM , Giniatullin Rashid , Nistri Andrea , Fabbretti Elsa
Published: August 2010

Background:

The R192Q mutation of the CACNA1A gene, encoding for the α1 subunit of voltage-gated P/Q Ca2+ channels (Cav2.1), is associated with familial hemiplegic migraine-1. We investigated whether this gain-of-function mutation changed the structure and function of trigeminal neuron P2X3 receptors that are thought to be important contributors to migraine pain.

Results:

Using in vitro trigeminal sensory neurons of a mouse genetic model knockin for the CACNA1A R192Q mutation, we performed patch clamp recording and intracellular Ca2+ imaging that showed how these knockin ganglion neurons generated P2X3 receptor-mediated responses significantly larger than wt neurons. These enhanced effects were reversed by the Cav 2.1 blocker ω-agatoxin. We, thus, explored intracellular signalling dependent on kinases and phosphatases to understand the molecular regulation of P2X3 receptors of knockin neurons. In such cells we observed strong activation of CaMKII reversed by ω-agatoxin treatment. The CaMKII inhibitor KN-93 blocked CaMKII phosphorylation and the hyperesponsive P2X3 phenotype. Although no significant difference in membrane expression of knockin receptors was found, serine phosphorylation of knockin P2X3 receptors was constitutively decreased and restored by KN-93. No change in threonine or tyrosine phosphorylation was detected. Finally, pharmacological inhibitors of the phosphatase calcineurin normalized the enhanced P2X3 receptor responses of knockin neurons and increased their serine phosphorylation.

Conclusions:

The present results suggest that the CACNA1A mutation conferred a novel molecular phenotype to P2X3 receptors of trigeminal ganglion neurons via CaMKII-dependent activation of calcineurin that selectively impaired the serine phosphorylation state of such receptors, thus potentiating their effects in transducing trigeminal nociception.
Displaced proximal humeral fractures: an Indian experience with locking plates
Authors: Aggarwal Sameer , Bali Kamal , Dhillon Mandeep S , Kumar Vishal , Mootha Aditya K
Published: August 2010

Background

The treatment of displaced proximal humerus fractures, especially in elderly, remains controversial. The objective of this study was to evaluate functional outcome of locking plate used for fixation of these fractures after open reduction. We also attempted to evaluate the complications and predictors of loss of fixation for such an implant.

Methods

Over two and a half years, 56 patients with an acute proximal humerus fracture were managed with locking plate osteosynthesis. 47 of these patients who completed a minimum follow up of 1 year were evaluated using Constant score calculation. Statistical analysis was done using SPSS 16 and a p value of less than 0.05 was taken as statistically significant.

Results

The average follow up period was around 21.5 months. Outcomes were excellent in 17%, good in 38.5%, moderate in 34% while poor in 10.5%. The Constant score was poorer for AO-OTA type 3 fractures as compared to other types. The scores were also inferior for older patients (> 65 years old). Complications included screw perforation of head, AVN, subacromial impingement, loss of fixation, axillary nerve palsy and infection. A varus malalignment was found to be a strong predictor of loss of fixation.

Conclusion

Locking plate osteosynthesis leads to satisfactory functional outcomes in all the patients. Results are better than non locking plates in osteoporotic fractures of the elderly. However the surgery has steep learning curve and various complications could be associated with its use. Nevertheless we believe that a strict adherence to the principles of locking plate use can ensure good result in such challenging fractures.
BACE1-/- mice exhibit seizure activity that does not correlate with sodium channel level or axonal localization
Authors: Hitt Brian D , Jaramillo Thomas C , Chetkovich Dane M , Vassar Robert
Published: August 2010

Background

BACE1 is a key enzyme in the generation of the Aβ peptide that plays a central role in the pathogenesis of Alzheimer's disease. While BACE1 is an attractive therapeutic target, its normal physiological function remains largely unknown. Examination of BACE1-/- mice can provide insight into this function and also help anticipate consequences of BACE1 inhibition. Here we report a seizure-susceptibility phenotype that we have identified and characterized in BACE1-/- mice.

Results

We find that electroencephalographic recordings reveal epileptiform abnormalities in some BACE1-/- mice, occasionally including generalized tonic-clonic and absence seizures. In addition, we find that kainic acid injection induces seizures of greater severity in BACE1-/- mice relative to BACE1+/+ littermates, and causes excitotoxic cell death in a subset of BACE1-/- mice. This hyperexcitability phenotype is variable and appears to be manifest in approximately 30% of BACE1-/- mice. Finally, examination of the expression and localization of the voltage-gated sodium channel α-subunit Nav1.2 reveals no correlation with BACE1 genotype or any measure of seizure susceptibility.

Conclusions

Our data indicate that BACE1 deficiency predisposes mice to spontaneous and pharmacologically-induced seizure activity. This finding has implications for the development of safe therapeutic strategies for reducing Aβ levels in Alzheimer's disease. Further, we demonstrate that altered sodium channel expression and axonal localization are insufficient to account for the observed effect, warranting investigation of alternative mechanisms.
Systems approach to investigating host-pathogen interactions in infections with the biothreat agent Francisella. Constraints-based model of Francisella tularensis
Authors: Raghunathan Anu , Shin Sookil , Daefler Simon
Published: August 2010

Background

Francisella tularensis is a prototypic example of a pathogen for which few experimental datasets exist, but for which copious high-throughout data are becoming available because of its re-emerging significance as biothreat agent. The virulence of Francisella tularensis depends on its growth capabilities within a defined environmental niche of the host cell.

Results

We reconstructed the metabolism of Francisella as a stoichiometric matrix. This systems biology approach demonstrated that changes in carbohydrate utilization and amino acid metabolism play a pivotal role in growth, acid resistance, and energy homeostasis during infection with Francisella. We also show how varying the expression of certain metabolic genes in different environments efficiently controls the metabolic capacity of F. tularensis. Selective gene-expression analysis showed modulation of sugar catabolism by switching from oxidative metabolism (TCA cycle) in the initial stages of infection to fatty acid oxidation and gluconeogenesis later on. Computational analysis with constraints derived from experimental data revealed a limited set of metabolic genes that are operational during infection.

Conclusions

This integrated systems approach provides an important tool to understand the pathogenesis of an ill-characterized biothreat agent and to identify potential novel drug targets when rapid target identification is required should such microbes be intentionally released or become epidemic.
Subchondral bone microstructural damage by increased remodelling aggravates experimental osteoarthritis preceded by osteoporosis
Authors: Bellido Miriam , Lugo Laura , Roman-Blas Jorge A , Castañeda Santos , Caeiro Jose R , Dapia Sonia , Calvo Emilio , Largo Raquel , Herrero-Beaumont Gabriel
Published: August 2010

Introduction

Osteoporosis (OP) increases cartilage damage in a combined rabbit model of OP and osteoarthritis (OA). Accordingly, we assessed whether microstructure impairment at subchondral bone aggravates cartilage damage in this experimental model.

Methods

OP was induced in 20 female rabbits, by ovariectomy and intramuscular injections of methylprednisolone hemisuccinate for four weeks. Ten healthy animals were used as controls. At week 7, OA was surgically induced in left knees of all rabbits. At 22 weeks, after sacrifice, microstructure parameters were assessed by micro-computed tomography, and osteoprotegerin (OPG), receptor activator of nuclear factor-κB ligand (RANKL), alkaline phosphatase (ALP) and metalloproteinase 9 (MMP9) protein expressions were evaluated by Western Blot at subchondral bone. In addition, cartilage damage was estimated using the histopathological Mankin score. Mann-Whitney and Spearman statistical tests were performed as appropriate, using SPSS software v 11.0. Significant difference was established at P < 0.05.

Results

Subchondral bone area/tissue area, trabecular thickness and polar moment of inertia were diminished in OPOA knees compared with control or OA knees (P < 0.05). A decrease of plate thickness, ALP expression and OPG/RANKL ratio as well as an increased fractal dimension and MMP9 expression occurred at subchondral bone of OA, OP and OPOA knees vs. controls (P < 0.05). In addition, the severity of cartilage damage was increased in OPOA knees vs. controls (P < 0.05). Remarkably, good correlations were observed between structural and remodelling parameters at subchondral bone, and furthermore, between subchondral structural parameters and cartilage Mankin score.

Conclusions

Microstructure impairment at subchondral bone associated with an increased remodelling aggravated cartilage damage in OA rabbits with previous OP. Our results suggest that an increased subchondral bone resorption may account for the exacerbation of cartilage damage when early OA and OP coexist simultaneously in same individuals.
Association of invasion-promoting tenascin-C additional domains with breast cancers in young women
Authors: Guttery David S , Hancox Rachael A , Mulligan Kellie T , Hughes Simon , Lambe Sinead M , Pringle J Howard , Walker Rosemary A , Jones J Louise , Shaw Jacqueline A
Published: August 2010

Introduction

Tenascin-C (TNC) is a large extracellular matrix glycoprotein that shows prominent stromal expression in many solid tumours. The profile of isoforms expressed differs between cancers and normal breast, with the two additional domains AD1 and AD2 considered to be tumour associated. The aim of the present study was to investigate expression of AD1 and AD2 in normal, benign and malignant breast tissue to determine their relationship with tumour characteristics and to perform in vitro functional assays to investigate the role of AD1 in tumour cell invasion and growth.

Methods

Expression of AD1 and AD2 was related to hypoxanthine phosphoribosyltransferase 1 as a housekeeping gene in breast tissue using quantitative RT-PCR, and the results were related to clinicopathological features of the tumours. Constructs overexpressing an AD1-containing isoform (TNC-14/AD1/16) were transiently transfected into breast carcinoma cell lines (MCF-7, T-47 D, ZR-75-1, MDA-MB-231 and GI-101) to assess the effect in vitro on invasion and growth. Statistical analysis was performed using a nonparametric Mann-Whitney test for comparison of clinicopathological features with levels of TNC expression and using Jonckheere-Terpstra trend analysis for association of expression with tumour grade.

Results

Quantitative RT-PCR detected AD1 and AD2 mRNA expression in 34.9% and 23.1% of 134 invasive breast carcinomas, respectively. AD1 mRNA was localised by in situ hybridisation to tumour epithelial cells, and more predominantly to myoepithelium around associated normal breast ducts. Although not tumour specific, AD1 and AD2 expression was significantly more frequent in carcinomas in younger women (age ≤40 years; P < 0.001) and AD1 expression was also associated with oestrogen receptor-negative and grade 3 tumours (P < 0.05). AD1 was found to be incorporated into a tumour-specific isoform, not detected in normal tissues. Overexpression of the TNC-14/AD1/16 isoform significantly enhanced tumour cell invasion (P < 0.01) and growth (P < 0.01) over base levels.

Conclusions

Together these data suggest a highly significant association between AD-containing TNC isoforms and breast cancers in younger women (age ≤40 years), which may have important functional significance in vivo.
Evolutionary divergence in the fungal response to fluconazole revealed by soft clustering
Authors: Kuo Dwight , Tan Kai , Zinman Guy , Ravasi Timothy , Bar-Joseph Ziv , Ideker Trey
Published: August 2010

Background

Fungal infections are an emerging health risk, especially those involving yeast that are resistant to antifungal agents. To understand the range of mechanisms by which yeasts can respond to anti-fungals, we compared gene expression patterns across three evolutionarily distant species - Saccharomyces cerevisiae, Candida glabrata and Kluyveromyces lactis - over time following fluconazole exposure.

Results

Conserved and diverged expression patterns were identified using a novel soft clustering algorithm that concurrently clusters data from all species while incorporating sequence orthology. The analysis suggests complementary strategies for coping with ergosterol depletion by azoles - Saccharomyces imports exogenous ergosterol, Candida exports fluconazole, while Kluyveromyces does neither, leading to extreme sensitivity. In support of this hypothesis we find that only Saccharomyces becomes more azole resistant in ergosterol-supplemented media; that this depends on sterol importers Aus1 and Pdr11; and that transgenic expression of sterol importers in Kluyveromyces alleviates its drug sensitivity.

Conclusions

We have compared the dynamic transcriptional responses of three diverse yeast species to fluconazole treatment using a novel clustering algorithm. This approach revealed significant divergence among regulatory programs associated with fluconazole sensitivity. In future, such approaches might be used to survey a wider range of species, drug concentrations and stimuli to reveal conserved and divergent molecular response pathways.
HLH54Fis required for the specification and migration of longitudinal gut muscle founders from the caudal mesoderm ofDrosophila
Authors: Ismat Afshan , Schaub Christoph , Reim Ingolf , Kirchner Katharina , Schultheis Dorothea , Frasch Manfred
Published: August 2010

HLH54F, the Drosophila ortholog of the vertebrate basic helix-loop-helix domain-encoding genes capsulin and musculin, is expressed in the founder cells and developing muscle fibers of the longitudinal midgut muscles. These cells descend from the posterior-most portion of the mesoderm, termed the caudal visceral mesoderm (CVM), and migrate onto the trunk visceral mesoderm prior to undergoing myoblast fusion and muscle fiber formation. We show that HLH54F expression in the CVM is regulated by a combination of terminal patterning genes and snail. We generated HLH54F mutations and show that this gene is crucial for the specification, migration and survival of the CVM cells and the longitudinal midgut muscle founders. HLH54F mutant embryos, larvae, and adults lack all longitudinal midgut muscles, which causes defects in gut morphology and integrity. The function of HLH54F as a direct activator of gene expression is exemplified by our analysis of a CVM-specific enhancer from the Dorsocross locus, which requires combined inputs from HLH54F and Biniou in a feed-forward fashion. We conclude that HLH54F is the earliest specific regulator of CVM development and that it plays a pivotal role in all major aspects of development and differentiation of this largely twist-independent population of mesodermal cells.
Old Franconian and Middle Dutch  and Velar Palatalization
Authors: van der Hoek Michel
Published: August 2010

Our understanding of the relative chronology and linguistic geography of velar palatalization in West Germanic remains limited. A major obstacle is the lack of evidence for the earlier stages of the western Franconian dialects. An examination of the origins of the spelling , common in medieval Dutch as well as in the Old High German Isidor, reveals a relationship with velar palatalization. The view that  goes back to Merovingian Latin and that its later use in Middle Dutch is a borrowing of an Old French spelling practice is untenable. Instead, the spelling is an internal development by Germanic scribes of an established model with diacritical  inherited from Latin. If Gmc. *g in the western Franconian dialects is analyzed as a voiced velar fricative, then the distinction  points to an opposition between velar and palatalized reflexes of Gmc. *g.
Die Textstruktur der ›Lex Burgundionum‹ und der ›Lex Salica‹
Authors: Seebold Elmar
Published: August 2010

The first part of the Lex Burgundionum corresponds in principle to the first part of the Lex Salica, but between the paragraphs of LB later material has been (unsystematically) introduced, whereas the regulations of LS have been extended and larger parts have been shifted to the beginning and the end of the original first part. Later additions in LB stand disconnectedly side by side, whereas to the original first part of LS a set of specifically Germanic regulations has been added.
Substitutionen in der minne. Lancelot und Ginover
Authors: Witthöft Christiane
Published: August 2010

To substitute an individual in most intimate proximity and to play sexual masquerade between the sexes appears to have been a global narrative pattern of various genres. The following considerations though are neither concerned with a widely noticed phenomenon of narration in general nor with the variety of comparable variants in respect to form and content but they are concentrating on a particular practice of narrative transformation. In ›Prose Lancelot‹ the dual substitution of Ginover touches the central meaning of an adultery love between her and Lancelot. It is reflecting the conflict of clerical and courtly discourse characteristic for ›Prose Lancelot‹. The substitution as narrative core is confronted with courtly, biblical and novellistic patterns of narration.
Offensive jokes: How do they impact long-term relationships?
Authors: Hall Jeffrey A. , Sereno Ken
Published: August 2010

This article explores the impact of the use of negative humor on relational satisfaction and the importance of humor in long-term relationships from a coorientation perspective. Dyadic data from 123 couples were gathered using a survey measuring positive and negative humor use. These data were analyzed using structural equations modeling and the Actor-Partner Independence Model (Kenny et al., Dyadic data analysis, The Guilford Press, 2006: 144). Negative humor weakly predicted relational outcomes, but was valuable when partners saw themselves as possessing a shared sense of humor. Men acknowledge that their own public negative humor use negatively impacts the importance of humor in their relationship. Perceived similarity in negative humor use positively predicts relational satisfaction for both partners, and positively predicts the importance of humor for men, regardless of how much positive humor the couple uses. Accurately knowing a partner's negative humor use, or having greater understanding, negatively predicted relational outcomes.
Prolactin secretion patterns: basic mechanisms and clinical implications for reproduction
Authors: Egli Marcel , Leeners Brigitte , Kruger Tillmann H C
Published: August 2010

Prolactin (PRL) is one of the most versatile hormones in the mammalian body affecting reproductive, sexual, metabolic, immune, and other functions. It is therefore not surprising that the neural control of PRL secretion is complex, involving the coordinated actions of several hypothalamic nuclei. A plethora of experimental data exists on the hypothalamic control of hormone secretion under various physiological stimuli. There have been even mathematical models and computer studies published, which help to understand the complex hypothalamic–pituitary network. Nevertheless, the putative role of PRL for human reproduction still has to be clarified. Here, we review data on the underlying mechanisms controlling PRL secretion using both experimental and mathematical approaches. These investigations primarily focus on rhythmic secretion in rats during early pregnancy or pseudopregnancy, and they point to the important role of oxytocin as a crucial PRL-releasing factor. Recent data on human studies and their theoretical and clinical implications are reviewed as well. In particular, studies demonstrating a sustained PRL surge after sexual climax in males and females are presented, indicating possible implications for both sexual satiation and reproductive functions. Taking these data together, there is evidence for the hypothesis that the PRL surge induced by sexual activity, together with the altered PRL rhythmic pattern, is important for successful initialization of pregnancy not only in rodents but also possibly in humans. However, further investigations are needed to clarify such a role in humans.
Globalization of Pediatric Research: Analysis of Clinical Trials Completed for Pediatric Exclusivity
Authors: Pasquali Sara K. , Burstein Danielle S. , Benjamin Daniel K. , Smith P. Brian , Li Jennifer S.
Published: August 2010

OBJECTIVE:

We evaluated the setting of published studies conducted under the US Pediatric Exclusivity Provision, which provides economic incentives to pharmaceutical companies to conduct drug studies with children.

METHODS:

Published studies containing the main results of trials conducted in 1998–2007 under the Pediatric Exclusivity Provision were included. Data were extracted from each study and described, including the therapeutic area of drug studied, number of patients enrolled, number of sites, and location where the study was conducted, if reported.

RESULTS:

Overall, 174 trials were included (sample size: 8–27 065 patients); 9% did not report any information regarding the location or number of sites where the study was conducted. Of trials that did report such information, 65% were conducted in ≥1 country outside the United States, and 11% did not include any sites in the United States. Fifty-four countries were represented, and 38% of trials enrolled patients in ≥1 site located in a developing/transition country, including more than one-third of infectious disease, cardiovascular, and allergy/immunology trials.

CONCLUSIONS:

The majority of published pediatric trials conducted under the Pediatric Exclusivity Provision included sites outside the United States, and more than one-third of trials enrolled patients in developing/transition countries.
Microwave dielectric properties and compatibility with silver of low-fired Ba5Nb4O15 ceramics by BaCu(B2O5) addition
Authors: Zhou Huanfu , Wang Hong , Zhang Minghuia , Yang Haibo
Published: August 2010

The influence of BaCu(B2O5) (BCB) addition on the sintering temperature and microwave dielectric properties of Ba5Nb4O15 ceramics has been investigated. The addition of small amount of BCB can effectively lower the sintering temperature of Ba5Nb4O15 ceramics from 1400 to 875 °C and induce no obvious degradation of the microwave dielectric properties. The reduced sintering temperature was attributed to the BCB liquid phase. Typically, the 1.5 wt% BCB-added Ba5Nb4O15 ceramic sintered at 875 °C for 2 h exhibited good microwave dielectric properties of Q × f = 28,655 GHz, εr = 40.2, and τf = 60 ppm/°C. The dielectric ceramic demonstrated stability against the reaction with the Ag electrode, which suggests that the ceramics could be applied in multilayer microwave devices requiring low sintering temperatures.
Formation of highly conductive composite coatings and their applications to broadband antennas and mechanical transducers
Authors: Liao Kang-Shyang , Talla Jamal A. , Yambem Soniya D. , Birx Donald , Chen Guo , Coldren Faith , Carroll David L. , Ci Lijie , Ajayan Pulickel M. , Zhang Donghui , Curran Seamus A.
Published: August 2010

Tight networks of interwoven carbon nanotube bundles are formed in our highly conductive composite. The composite possesses properties suggesting a two-dimensional percolative network rather than other reported dispersions displaying three-dimensional networks. Binding nanotubes into large but tight bundles dramatically alters the morphology and electronic transport dynamics of the composite. This enables it to carry higher levels of charge in the macroscale leading to conductivities as high as 1600 S/cm. We now discuss in further detail, the electronic and physical properties of the nanotube composites through Raman spectroscopy and transmission electron microscopy analysis. When controlled and used appropriately, the interesting properties of these composites reveal their potential for practical device applications. For instance, we used this composite to fabricate coatings, which improve the properties of an electromagnetic antenna/amplifier transducer. The resulting transducer possesses a broadband range up to GHz frequencies. A strain gauge transducer was also fabricated using changes in conductivity to monitor structural deformations in the composite coatings.
Hybrid processing and properties of Ni0.8Zn0.2Fe2O4/Ba0.6Sr0.4TiO3magnetodielectric composites
Authors: Yang Haibo , Wang Hong , Shui Li , He Li
Published: August 2010

Ni0.8Zn0.2Fe2O4/Ba0.6Sr0.4TiO3(NZO/BST) composites with high permittivity and low loss were synthesized via the hybrid processing route. The composites possess very dense and homogenous microstructure. The NZO/BST composites show good dielectric properties and magnetic properties with low loss in high frequency range. This indicates that this kind of magnetodielectric composites can be used in high-frequency communications for the capacitor-inductor integrating devices such as electromagnetic interference filters and antennas. The permittivities of the composites were also fitted using the combination of Maxwell–Wagner polarization and modified Curie–Weiss law.
Secondary IMC formation induced by Kirkendall voiding in Cu/Sn–3.5Ag solder joints
Authors: Kim S.H. , Yu Jin
Published: August 2010

In this investigation on the formation of multiple-layered Kirkendall voids at Cu/Sn–3.5Ag solder joints, Sn–3.5Ag solder balls were reacted with Cu under bump metallurgy (UBM), which was electroplated using bis-sodium sulfopropyl–disulfide, C6H12O6S4Na2 (SPS) additive. The sequence of multilayer Kirkendall voids and Cu–Sn IMC (intermetallic compounds) formations are explained with the aid of cross-sectional scanning electron microscopy (SEM) micrographs and schematic diagrams. During the aging treatment at 150 °C, layers of Cu6Sn5/Cu3Sn formed at the solder joints and Kirkendall voids nucleated at the Cu3Sn/Cu interface as a result of the segregation of residual S originating from SPS. However, with Kirkendall void growth, the net section area of the Cu/Cu3Sn interface decreased and the Cu flux into Cu3Sn was inhibited. As the atomic ratio of Cu against Sn in the Cu3Sn dropped, transformation of Cu3Sn into Cu6Sn5 ensued. Subsequent diffusion of Sn atoms into the remaining Cu UBM through the remaining ligament of the Cu6Sn5/Cu interface precipitated secondary Cu3Sn beneath the primary Cu3Sn/Cu interface, and the secondary Kirkendall voids formed at the new Cu3Sn/Cu interface and so on.
Structural origin of the high glass-forming ability in Y-doped bulk metallic glasses
Authors: Yang Liang , Guo Gu-Qing , Zhang Guo-Qing , Chen Lian-Yi
Published: August 2010

Structural origin of the high glass-forming ability (GFA) in multicomponent bulk metallic glasses (BMGs) caused by minor alloying was investigated using state-of-the-art synchrotron radiation techniques. It is found that a two-shell icosahedral cluster with one Y center is the basic structural unit in the representative Cu46Zr42Al7Y5 BMG, which may be densely packed with the help of shared and glue atoms, leading to enhanced ordering at short and medium range. This cluster dense packing may play a key role in achieving the high GFA in CuZrAlY alloy, which also explains the strong dependence of GFA on Y content observed in many experiments. The present work may be extended to a series of multicomponent amorphous alloys, the formation of which is strongly dependent on minor alloying.
Flowerlike submicrometer gold particles: Size- and surface roughness-controlled synthesis and electrochemical characterization
Authors: Shan Changsheng , Han Dongxue , Song Jiangfeng , Ivaska Ari , Niu Li
Published: August 2010

Flowerlike submicrometer gold particles were synthesized through a simple one-step method using p-diaminobenzene as a reductant in the presence of poly(sodium 4-styrenesulfonate) in aqueous solution. The particle size with diameters ranging from 267 to 725 nm could be tuned by varying the molar ratio of poly(sodium 4-styrenesulfonate) to HAuCl4, which also resulted in tunable roughness. The gold particles were confirmed by scanning electron microscopy, energy dispersive x-ray spectroscopy, x-ray diffraction, and x-ray photoelectron spectroscopy. Cyclic voltammetry showed that the specific surface area of the flowerlike particles was larger than that of sphere particles. The obtained flowerlike particles with higher surface area also exhibited higher electrocatalytic activity toward H2O2 and O2. The increase of electrocatalytic activity could be attributed to the increase of the active surface area.
Temperature-dependent broadband near-infrared luminescence in silicate glass ceramics containing Li2MgSiO4: Cr4+ nanocrystals
Authors: Zhuang Yixi , Zhou Jiajia , Xie Junhua , Teng Yu , Qiu Jianrong
Published: August 2010

Transparent glass ceramics containing Li2MgSiO4: Cr4+ nanocrystallites were prepared. Intense broadband near-infrared emission with full width at half-maximum larger than 200 nm and long fluorescence lifetime (τ > 100 μs) were observed. The temperature-dependent optical characteristics of the glass ceramics containing Li2MgSiO4: Cr4+ crystallites were compared to those of Li2MgSiO4: Cr4+ single crystals. The reason for extra-long near-infrared fluorescence lifetime was illuminated by the mixed effect between 3T2 and 1E levels. The crystal-filed-induced particular energy-level scheme makes the fluorescence lifetime of the glass ceramics containing Li2MgSiO4: Cr4+ crystallites one order longer than those of other Cr4+-doped glass ceramics.
A Noninterventional Study Documenting Use and Success of Implants With a New Chemically Modified Titanium Surface in Daily Dental Practice
Authors: Luongo Giuseppe , Oteri Giacomo
Published: August 2010

A new chemically modified titanium surface, SLActive, has recently been developed. The results obtained in controlled clinical trials indicate that this implant can be safely used and that it offers predictable results. The goal of this noninterventional study was to verify that the success rates of implants used in daily dental practice are comparable to those reported in controlled clinical trials. This study was a prospective, noninterventional study using implants with a chemically modified surface according to the daily dental practice procedures applied by private practitioners. The choice of the implantation procedure and the loading protocol were the responsibility of the investigator and were chosen according to the patient's needs. Thirty clinical centers actively participated in this study, and 226 patients were treated, of which, 8 patients were lost to follow-up. Because of the noninterventional design of the study, the patients were not selected according to strictly defined inclusion/exclusion criteria. Thus, the study included individuals with risk factors such as smoking (24%), untreated gingivitis or periodontitis (9%), and bruxism (6%). The implants were equally distributed between mandible (46%) and maxilla (54%). A bone augmentation procedure was done in 31% of the cases. Early loading (functional loading between 48 hours and 3 months after implant insertion) was applied most frequently (48%), followed by the conventional loading protocol (3 to 6 months after implant placement, 34%). Immediate restoration and immediate loading were rare (7% and 2%, respectively). Of 276 implants inserted and documented, 5 implants failures were reported, all of which were associated with a sinus floor augmentation procedure. The survival rate was 98.2% at the 1-year follow-up visit. The results showed that implants with a chemically modified surface can be successfully restored with success rates similar to those reported in formal clinical trials under more controlled conditions.
Extremely broadband and wide‐angle retardation films
Authors: Kwok H. S. , Yu X. J.
Published: August 2010

Abstract— The design and construction of retardation films with any desired dispersion properties is reported. The method is simple and requires only conventional uniaxial retardation films. As an example, the design of retardation films which have constant retardation over the entire visible spectrum is demonstrated. The design methodology will be given. Specific design examples for broadband achromatic quarter‐wave and half‐wave retardation films are disclosed. These films show almost no wavelength dependence even at large viewing angles.
Measuring and modeling per‐element angular visibility in multi‐view displays
Authors: Boev Atanas , Bregovic Robert , Gotchev Atanas
Published: August 2010

Abstract—Multi‐view displays employ an optical layer which distributes the light of an underlying TFT‐LCD panel in different directions. Certain properties of the layer create specific artifacts, such as ghost images, moiré patterns, and masking. The layer was modeled as an image‐processing channel, and the display parameters related with the model were identified, which are importantfor the design of image‐processing algorithms for artifact mitigation. The identified parameters are interleaving pattern, angular visibility, and frequency throughput of the display. A methodology for deriving these parameters for an arbitrary LCD‐based multi‐view display are presented, which does not require precisely positioned measurement equipment. As a case study, measurement and modeling results for a particular multi‐view display are also presented.
Design conditions for attractive reality in mobile‐type 3‐D display
Authors: Tsuboi Masashi , Kimura Shinji , Takaki Yasuhiro , Horikoshi Tsutomu
Published: August 2010

Abstract—An autostereoscopic 3‐D display suitable for the mobile environment is prototyped and evaluated. First, the required conditions for a 3‐D display in a mobile environment are considered, and the three major requirements are clarified: small size, viewing‐position flexibility, and application support. An application of a mobile‐type 3‐D display should be different from that of a large‐sized 3‐D display because a mobile‐type 3‐D display cannot realize the feeling of immersion while large‐sized 3‐D displays can realize it easily. From this assumption, it is considered that it is important to realize the feeling to handle a 3‐D image. Three types of 3‐D displays are developed to satisfy these requirements. They are subjectively evaluated to confirm their attractiveness. Results of the tests show that intuitive interaction can increase the reality of the 3‐D image in the sense of unity and also can improve the solidity and depth impression of the 3‐D image.
Recreation‐induced changes in boreal bird communities in protected areas
Authors: Kangas K. , Luoto M. , Ihantola A. , Tomppo E. , Siikamäki P.
Published: August 2010

The impacts of human‐induced disturbance on birds have been studied in growing extent, but there are relatively few studies about the effects of recreation on forest bird communities in protected areas. In this paper, the relative importance of recreation as well as environmental variables on bird communities in Oulanka National Park, in northeastern Finland, was investigated using general additive models (GAM). Bird data collected using the line transect method along hiking trails and in undisturbed control areas were related to number of visits, area of tourism infrastructure, and habitat variables. We further examined the impact of spatial autocorrelation by calculating an autocovariate term for GAMs. Our results indicate that number of visits affects the occurrence and composition of bird communities, but it had no impact on total species richness. Open‐cup nesters breeding on the ground showed strongest negative response to visitor pressure, whereas the open‐cup nesters nesting in trees and shrubs were more tolerant. For cavity‐nesting species, recreation had no significant impact. The contribution of the number of visits was generally low also in models in which it was selected, and the occurrence of birds was mainly determined by habitat characteristics of the area. However, our results show that the recreation‐induced disturbance with relatively low visitor pressure can have negative impacts on some bird species and groups of species and should be considered in management of protected areas with recreational activities.
Linking River, Floodplain, and Vadose Zone Hydrology to Improve Restoration of a Coastal River Affected by Saltwater Intrusion
Authors: Kaplan D. , Muñoz‐Carpena R. , Wan Y. , Hedgepeth M. , Zheng F. , Roberts R. , Service R. Rossmanith
Published: August 2010

Floodplain forests provide unique ecological structure and function, which are often degraded or lost when watershed hydrology is modified. Restoration of damaged ecosystems requires an understanding of surface water, groundwater, and vadose (unsaturated) zone hydrology in the floodplain. Soil moisture and porewater salinity are of particular importance for seed germination and seedling survival in systems affected by saltwater intrusion but are difficult to monitor and often overlooked. This study contributes to the understanding of floodplain hydrology in one of the last bald cypress [Taxodium distichum (L.) Rich.] floodplain swamps in southeast Florida. We investigated soil moisture and porewater salinity dynamics in the floodplain of the Loxahatchee River, where reduced freshwater flow has led to saltwater intrusion and a transition to salt‐tolerant, mangrove‐dominated communities. Twenty‐four dielectric probes measuring soil moisture and porewater salinity every 30 min were installed along two transects—one in an upstream, freshwater location and one in a downstream tidal area. Complemented by surface water, groundwater, and meteorological data, these unique 4‐yr datasets quantified the spatial variability and temporal dynamics of vadose zone hydrology. Results showed that soil moisture can be closely predicted based on river stage and topographic elevation (overall Nash–Sutcliffe coefficient of efficiency = 0.83). Porewater salinity rarely exceeded tolerance thresholds (0.3125 S m−1) for bald cypress upstream but did so in some downstream areas. This provided an explanation for observed vegetation changes that both surface water and groundwater salinity failed to explain. The results offer a methodological and analytical framework for floodplain monitoring in locations where restoration success depends on vadose zone hydrology and provide relationships for evaluating proposed restoration and management scenarios for the Loxahatchee River.
The Origin and Fate of Arsenic in Coalbed Natural Gas–Produced Water Ponds
Authors: Sowder J. T. , Kelleners T. J. , Reddy K. J.
Published: August 2010

Coalbed natural gas (CBNG)–produced water contains small amounts of trace metals that can accumulate over time in produced water retention ponds. Within the Powder River Basin (PRB) of Wyoming, high concentrations of trace metals in pond water and their effect on shallow groundwater are potential concerns. A pond with a maximum As concentration of 146 mg L−1 was studied in detail to determine the potential for groundwater pollution and to explain the cause for the high concentration of As. Infiltration characteristics, subsurface hydrology, outfall and pond water quality, isotope signatures, and trace metal balances were examined to assess the hydrology and geochemistry of the pond. The results indicated minimum or no infiltration of pond water and no measurable contamination of the shallow groundwater. The high As concentrations in the pond were determined to be the result of semi‐continuous inputs of CBNG‐produced water with low As concentrations (0.20–0.48 mg L−1), exasperated by low pond volumes during drought conditions. Because of reduced infiltration and high evaporation rates, As became concentrated over time. Reduced infiltration was most likely caused by the high sodium concentration and high sodium adsorption ratio of the CBNG‐produced water, which disrupt soil structure. The findings for the pond and the techniques used may serve as a template for future impact assessments of other CBNG‐produced water ponds and are relevant for the approximately 4000 ponds currently permitted in the PRB and for future ponds. Further studies are recommended in the use of playa landforms to store marginal‐quality produced water.
Phosphorus Release from Ash and Remaining Tissues of Two Wetland Species after a Prescribed Fire
Authors: Liu G. D. , Gu B. , Miao S. L. , Li Y. C. , Migliaccio K. W. , Qian Y.
Published: August 2010

Dead plant tissues and ash from a prescribed fire play an important role in nutrient balance and cycling in the Florida Everglades ecosystem. The objective of this study was to assess the dynamic changes in total phosphorus release (TPr) from ash or tissues of either cattail (Typha domingensis Pers.) or sawgrass (Cladium jamaicense Crantz) to water. Natural‐dead (senesced‐dead) and burning‐dead (standing‐dead due to a prescribed fire) cattail and sawgrass were collected from highly (H) and moderately (M) impacted zones in the Florida Everglades. This experiment was conducted by incubation and water‐extraction of the materials in plastic bottles for 65 d at room temperature (24 ± 1°C). Results showed that 63 to 88%, 17 to 48%, 9 to 20%, and 13 to 28% of total P (TPp) were released as TPr from cattail and sawgrass ash, cattail tissues from the H zone, cattail tissues, and sawgrass tissues from the M zone, respectively. TPp means total P of plant tissues, whereas TPr is total P release from the tissues or ash. Most of the TPr was released within 24 h after burning. The quick release of TPr observed in this experiment may help explain the P surge in the surface water immediately following a fire in the marsh. These findings suggest that prescribed burning accelerates P release from cattail and sawgrass. They also imply that it is very important to keep the water stagnant in the first 24 h to maximize the benefits of a prescribed fire in the Everglades.
Lateral Movement of Soil Fumigants 1,3‐Dichloropropene and Chloropicrin from Treated Agricultural Fields
Authors: Wang D. , Gao S. , Qin R. , Browne G.
Published: August 2010

The soil fumigants 1,3‐dichloropropene (1,3‐D) and chloropicrin (CP) are often used for controlling soil‐borne plant pathogens and parasitic nematodes before reestablishing new vineyards and orchards. To evaluate crop safety and environmental risks with the replant fumigation, four field experiments were performed over 2 yr to examine 1,3‐D and CP lateral movement away from the treated fields. Shank injection with or without a virtually impermeable film (VIF) was used in two vineyard fumigation experiments, and spot drip application without tarp cover was used in two orchard experiments. Results showed that 1,3‐D and CP gases moved laterally to 6 m from the treated fields when the fumigants were applied by shank injection. The maximum 1,3‐D or CP soil gas concentration at 6 m was approximately 10 ng cm−3 when the fumigated plot was not cover with a tarp. With VIF, the measured maximum concentration increased to approximately 100 ng cm−3 In the spot drip application, maximum 1,3‐D and CP gas concentrations reached approximately 100 ng cm−3 but at 1.5 m radial distance from the point of fumigant injection.
Water Quality Trends at Inflows to Everglades National Park, 1977–2005
Authors: Hanlon E. A. , Fan X. H. , Gu B. , Migliaccio K. W. , Li Y. C. , Dreschel T. W.
Published: August 2010

Restoration of the Florida Everglades is important for the health of the natural system, including both the “River of Grass” and its downstream estuaries. Water quality improvement is one indicator of successful restoration in this complex ecosystem. Using the period of record of 1977 through 2005, we evaluated data from seven inflow sites to the Everglades National Park (ENP) for temporal trends of various forms of phosphorus (P) and nitrogen (N) and analyzed them using principal component analysis and factor analysis without flow adjustments. Locally estimated scatter plot smoothing (LOESS) trend lines identified two inflection points (three time periods) of changing trend in total P (TP) concentration at the seven sites. Results indicated that overall water quality in ENP inflow improved from 1977 to 2005, with significant downward trends in TP concentration. The overall trend of TP is probably mediated by hydrology, which is evident by a negative relationship between flow and annual average TP concentration at the majority of stations within the available data, although additional changes in vegetation due to hydroperiod may have some effects. Total N (TN), total Kjeldahl N, and total organic N concentrations also generally decreased at inflow sites. Water quality standards for TP, TN, and NH4+–N were exceeded at selected sites during the study period. Principle component analysis and factor analysis detected a grouping of sampling sites related to the water delivery system that could be used as indicators to better manage monitoring resources. Study results suggest that water quality data analyses could provide additional insight into the success of a restoration management plan and on how monitoring may be modified for more efficient use of resources.
Runoff Losses of Sediment and Phosphorus from No‐Till and Cultivated Soils Receiving Dairy Manure
Authors: Verbree David A. , Duiker Sjoerd W. , Kleinman Peter J.A.
Published: August 2010

Managing manure in no‐till systems is a water quality concern because surface application of manure can enrich runoff with dissolved phosphorus (P), and incorporation by tillage increases particulate P loss. This study compared runoff from well‐drained and somewhat poorly drained soils under corn (Zea mays, L.) production that had been in no‐till for more than 10 yr. Dairy cattle (Bos taurus L.) manure was broadcast into a fall planted cover crop before no‐till corn planting or incorporated by chisel/disk tillage in the absence of a cover crop. Rainfall simulations (60 mm h−1) were performed after planting, mid‐season, and post‐harvest in 2007 and 2008. In both years and on both soils, no‐till yielded significantly less sediment than did chisel/disking. Relative effects of tillage on runoff and P loss differed with soil. On the well‐drained soil, runoff depths from no‐till were much lower than with chisel/disking, producing significantly lower total P loads (22–50% less). On the somewhat poorly drained soil, there was little to no reduction in runoff depth with no‐till, and total P loads were significantly greater than with chisel/disking (40–47% greater). Particulate P losses outweighed dissolved P losses as the major concern on the well‐drained soil, whereas dissolved P from surface applied manure was more important on the somewhat poorly drained soil. This study confirms the benefit of no‐till to erosion and total P runoff control on well‐drained soils but highlights trade‐offs in no‐till management on somewhat poorly drained soils where the absence of manure incorporation can exacerbate total P losses.