bluuebunny/crossref_metadata_2025 huggingface dataset:
Spectrally Consistent Scattering, Absorption, and Polarization Properties of Atmospheric Ice Crystals at Wavelengths from 0.2 to 100 μm
Authors: Yang Ping , Bi Lei , Baum Bryan A. , Liou Kuo-Nan , Kattawar George W. , Mishchenko Michael I. , Cole Benjamin
Published: September 2012

A data library is developed containing the scattering, absorption, and polarization properties of ice particles in the spectral range from 0.2 to 100 μm. The properties are computed based on a combination of the Amsterdam discrete dipole approximation (ADDA), the T-matrix method, and the improved geometric optics method (IGOM). The electromagnetic edge effect is incorporated into the extinction and absorption efficiencies computed from the IGOM. A full set of single-scattering properties is provided by considering three-dimensional random orientations for 11 ice crystal habits: droxtals, prolate spheroids, oblate spheroids, solid and hollow columns, compact aggregates composed of eight solid columns, hexagonal plates, small spatial aggregates composed of 5 plates, large spatial aggregates composed of 10 plates, and solid and hollow bullet rosettes. The maximum dimension of each habit ranges from 2 to 10 000 μm in 189 discrete sizes. For each ice crystal habit, three surface roughness conditions (i.e., smooth, moderately roughened, and severely roughened) are considered to account for the surface texture of large particles in the IGOM applicable domain. The data library contains the extinction efficiency, single-scattering albedo, asymmetry parameter, six independent nonzero elements of the phase matrix (P11, P12, P22, P33, P43, and P44), particle projected area, and particle volume to provide the basic single-scattering properties for remote sensing applications and radiative transfer simulations involving ice clouds. Furthermore, a comparison of satellite observations and theoretical simulations for the polarization characteristics of ice clouds demonstrates that ice cloud optical models assuming severely roughened ice crystals significantly outperform their counterparts assuming smooth ice crystals.
Incorporating the Effects of 3D Radiative Transfer in the Presence of Clouds into Two-Stream Multilayer Radiation Schemes
Authors: Hogan Robin J. , Shonk Jonathan K. P.
Published: September 2012

This paper presents a new method for representing the important effects of horizontal radiation transport through cloud sides in two-stream radiation schemes. Ordinarily, the radiative transfer equations are discretized separately for the clear and cloudy regions within each model level, but here terms are introduced that represent the exchange of radiation laterally between regions and the resulting coupled equations are solved for each layer. This approach may be taken with both the direct incoming shortwave radiation, which is governed by Beer’s law, and the diffuse shortwave and longwave radiation, governed by the two-stream equations. The rate of lateral exchange is determined by the area of cloud “edge.” The validity of the method is demonstrated by comparing with rigorous 3D radiative transfer calculations in the literature for two cloud types in which the 3D effect is strong, specifically cumulus and aircraft contrails. The 3D effect on shortwave cloud radiative forcing varies between around −25% and around +100%, depending on solar zenith angle. Even with an otherwise very simplistic representation of the cloud, the new scheme exhibits good agreement with the rigorous calculations in the shortwave, opening the way for efficient yet accurate representation of this important effect in climate models.
The Regional Atmospheric Water Budget over Southwestern Germany under Different Synoptic Conditions
Authors: Sasse Romi , Schädler Gerd , Kottmeier Christoph
Published: September 2012

This study addresses the question of how complex topography in a low-mountain region affects the partitioning and the variability of the atmospheric water budget components (WBCs) as a function of synoptic-scale flow conditions. The WBCs are calculated for regions of different size and location in southwestern Germany and the summer months from 2005 to 2009 using the high-resolution regional climate model COSMO-CLM driven by Global Model (GME) analyses. Comparisons with observations from the Convective and Orographically-induced Precipitation Study (COPS) performed in summer 2007 show that the model is capable of simulating the atmospheric water budget reasonably (absolute mean error between 0.1 and 0.7 kg m−2 day−1). To investigate the influence of synoptic weather conditions, the daily WBCs are classified based on the inflow direction of the air masses and the cyclonality at 500 hPa. Using statistical tests, four groups out of the six synoptic conditions have significantly different distributions of the WBCs. This can be explained by differences in the air mass features and the influence of high/low pressure systems. The sensitivity of the modeled WBCs to topography and land cover is investigated by comparing a region in the flat upper Rhine Valley with one in the mountainous Black Forest/Swabian Jura. Compared to the Rhine Valley, increases of evapotranspiration (+5% to +16%), precipitation (+26% to +57%), and moisture convergence (+24% to +93%) are noticeable in the low-mountain region. Local modifications of the synoptic-scale flow, thermally induced winds, and land use cause this intensification of the atmospheric water budget, especially on the windward slopes of the mountains.
Dissipation of Turbulent Kinetic Energy Inferred from Seagliders: An Application to the Eastern Nordic Seas Overflows
Authors: Beaird Nicholas , Fer Ilker , Rhines Peter , Eriksen Charles
Published: September 2012

Turbulent mixing is an important process controlling the descent rate, water mass modification, and volume transport augmentation due to entrainment in the dense overflows across the Greenland–Scotland Ridge. These overflows, along with entrained Atlantic waters, form a major portion of the North Atlantic Deep Water, which pervades the abyssal ocean. Three years of Seaglider observations of the overflows across the eastern Greenland–Scotland Ridge are leveraged to map the distribution of dissipation of turbulent kinetic energy on the Iceland–Faroe Ridge. A method has been applied using the finescale vertical velocity and density measurements from the glider to infer dissipation. The method, termed the large-eddy method (LEM), is compared with a microstructure survey of the Faroe Bank Channel (FBC). The LEM reproduces the patterns of dissipation observed in the microstructure survey, which vary over several orders of magnitude. Agreement between the inferred LEM and more direct microstructure measurements is within a factor of 2. Application to the 9432 dives that encountered overflow waters on the Iceland–Faroe Ridge reveals three regions of enhanced dissipation: one downstream of the primary FBC sill, another downstream of the secondary FBC sill, and a final region in a narrow jet of overflow along the Iceland shelf break.
Massive Flap Donor Sites and the Role of Negative Pressure Wound Therapy
Authors: Schmedes Gregg W. , Banks Caroline A. , Malin Barry T. , Srinivas Pamela B. , Skoner Judith M.
Published: September 2012

Objective

Report our experience with negative pressure wound therapy (NPWT) applied to massive scapular and latissimus free flap donor sites, in the setting of microvascular reconstruction for extensive head and neck defects.

Study Design

Retrospective case series with chart review.

Setting

Tertiary academic referral center.

Subjects and Methods

Retrospective review was conducted of all patients who underwent scapular or latissimus free tissue transfer by the senior author for head and neck reconstruction, over a 5‐year period (2006‐2011). In addition to NPWT details, comprehensive patient data were abstracted and compiled, including demographics, operative details, hospital stay, postoperative follow‐up, and donor site complications.

Results

Ninety‐four patients underwent reconstruction of extensive postablative head and neck defects using either a scapular or latissimus free flap. Mean harvested flap skin paddle size was 140 cm2. All donor sites were closed primarily. Fifty‐two patients (55%) had NPWT applied over closed donor site incisions postoperatively. The other 42 patients (45%) received only conventional incision care. Major donor site complications occurred in 12% (n = 5) of the patients who did not undergo NPWT, as compared with a 6% (n = 3) complication rate among patients in the NPWT‐treated group.

Conclusion

This is the first study to examine NPWT in the postoperative treatment of closed high‐tension wounds following scapular or latissimus dorsi harvest for reconstruction of extensive head and neck defects. Our results suggest that NPWT is a safe technique in the management of massive scapular and latissimus free flap harvest sites that may decrease associated major donor wound complications.
Simultaneous SNP identification and assessment of allele-specific bias from ChIP-seq data
Authors: Ni Yunyun , Weber Hall Amelia , Battenhouse Anna , Iyer Vishwanath R
Published: September 2012

Background

Single nucleotide polymorphisms (SNPs) have been associated with many aspects of human development and disease, and many non-coding SNPs associated with disease risk are presumed to affect gene regulation. We have previously shown that SNPs within transcription factor binding sites can affect transcription factor binding in an allele-specific and heritable manner. However, such analysis has relied on prior whole-genome genotypes provided by large external projects such as HapMap and the 1000 Genomes Project. This requirement limits the study of allele-specific effects of SNPs in primary patient samples from diseases of interest, where complete genotypes are not readily available.

Results

In this study, we show that we are able to identify SNPs de novo and accurately from ChIP-seq data generated in the ENCODE Project. Our de novo identified SNPs from ChIP-seq data are highly concordant with published genotypes. Independent experimental verification of more than 100 sites estimates our false discovery rate at less than 5%. Analysis of transcription factor binding at de novo identified SNPs revealed widespread heritable allele-specific binding, confirming previous observations. SNPs identified from ChIP-seq datasets were significantly enriched for disease-associated variants, and we identified dozens of allele-specific binding events in non-coding regions that could distinguish between disease and normal haplotypes.

Conclusions

Our approach combines SNP discovery, genotyping and allele-specific analysis, but is selectively focused on functional regulatory elements occupied by transcription factors or epigenetic marks, and will therefore be valuable for identifying the functional regulatory consequences of non-coding SNPs in primary disease samples.
An expanded myeloid derived suppressor cell population does not play a role in gammaherpesvirus-exacerbated breast cancer metastases
Authors: Nelson Daniel A , Chauhan Vinita S , Tolbert Melanie D , Bost Kenneth L
Published: September 2012

Background

Mice latently infected with murine gammaherpesvirus 68 (HV-68) and transplanted with 4 T1 breast cancer cells developed exacerbated metastatic lesions when compared to controls. The mechanisms responsible for this viral-exacerbated disease were not clear. The ability of HV-68 infection to induce S100A8 and S100A9 production and to expand a population of CD11b+Gr-1+ cells suggested that increased numbers, or activity, of viral-expanded myeloid derived suppressor cells (MDSCs) might contribute to HV-68-associated metastatic breast cancer in this model. We questioned whether mock or HV-68 infected mice with significant breast cancer might have differences in the number and/or activity of MDSCs.

Methods

Myeloid-derived macrophages and dendritic cells were isolated from normal mice and cultured in vitro with HV-68 to assess S100A8 and S100A9 mRNA and protein expression. In vivo studies were performed using groups of mice that were mock treated or infected with HV-68. After viral latency was established, 4 T1 breast cancer cells were transplanted in mice. When primary breast tumors were present mice were euthanized and cells isolated for phenotyping of myeloid cell populations using FACS, and for ex vivo analysis of suppressor activity. Serum from these animals was also collected to quantify S100A8 and S100A9 levels.

Results

In vitro studies demonstrated that direct exposure of myeloid cells to HV-68 did not induce increased expression of S100A8 or S100A9 mRNAs or secreted protein. HV-68 infected mice with metastatic breast cancer disease had no increases in S100A8/A9 levels and no significant increases in the numbers or activation of CD11b+Gr-1+MDSCs when compared to mock treated mice with breast cancer.

Conclusions

Together these studies are consistent with the notion that expanded myeloid derived suppressor cells do not play a role in gammaherpesvirus-exacerbated breast cancer metastases. The mechanisms responsible for HV-68 induced exacerbation of metastatic breast cancer remain unclear.
Population genetic structure of the malaria vector Anopheles funestus, in a recently re-colonized area of the Senegal River basin and human-induced environmental changes
Authors: Samb Badara , Dia Ibrahima , Konate Lassana , Ayala Diego , Fontenille Didier , Cohuet Anna
Published: September 2012

Background

Anopheles funestus is one of the major malaria vectors in tropical Africa. Because of several cycles of drought events that occurred during the 1970s, this species had disappeared from many parts of sahelian Africa, including the Senegal River basin. However, this zone has been re-colonized during the last decade by An. funestus, following the implementation of two dams on the Senegal River. Previous studies in that area revealed heterogeneity at the biological and chromosomal level among these recent populations.

Methods

Here, we studied the genetic structure of the newly established mosquito populations using eleven microsatellite markers in four villages of the Senegal River basin and compared it to another An. funestus population located in the sudanian domain.

Results

Our results presume Hardy Weinberg equilibrium in each An. funestus population, suggesting a situation of panmixia. Moreover, no signal from bottleneck or population expansion was detected across populations. The tests of genetic differentiation between sites revealed a slight but significant division into three distinct genetic entities. Genetic distance between populations from the Senegal River basin and sudanian domain was correlated to geographical distance. In contrast, sub-division into the Senegal River basin was not correlated to geographic distance, rather to local adaptation.

Conclusions

The high genetic diversity among populations from Senegal River basin coupled with no evidence of bottleneck and with a gene flow with southern population suggests that the re-colonization was likely carried out by a massive and repeated stepping-stone dispersion starting from the neighboring areas where An. funestus endured.
Growth Hormone Secretagogues Preserve the Electrophysiological Properties of Mouse Cardiomyocytes Isolated from in Vitro Ischemia/Reperfusion Heart
Authors: Ma Yi , Zhang Lin , Launikonis Bradley S. , Chen Chen
Published: September 2012

Ischemic heart diseases often induce cardiac arrhythmia with irregular cardiac action potential (AP). This study aims to demonstrate that GH secretagogues (GHS) ghrelin and its synthetic analog hexarelin can preserve the electrophysiological properties of cardiomyocytes experiencing ischemia/reperfusion (I/R). Isolated hearts from adult male mice underwent 20 min global ischemia followed by 30 min reperfusion using a Langendorff apparatus. Ghrelin (10 nm) or hexarelin (1 nm) was administered in the perfusion solution either 10 min before or after ischemia, termed pre- or posttreatments. Cardiomyocytes isolated from these hearts were used for whole-cell patch clamping to measure AP, voltage-gated L-type calcium current (ICaL), transient outward potassium current (Ito), and sodium current (INa). AP amplitude and duration were significantly decreased by I/R, but GHS treatments maintained their normality. GHS treatments prevented the decrease in ICaL and INa after I/R, thereby maintaining AP amplitude. Although the significant increase in Ito after I/R partially explained the shortened AP duration, the normalization of it by GHS treatments might contribute to the preservation of AP duration. Phosphorylated p38 and c-Jun NH2-terminal kinase and the downstream active caspase-9 in the cellular apoptosis pathway were significantly increased after I/R but not when GHS treatments were included, whereas phosphorylation of ERK1/2 associated with cell survival showed increase after I/R and a further increase after GHS treatments by binding to its receptor GHS receptor type 1a. These results suggest GHS can not only preserve the electrophysiological properties of cardiomyocytes after I/R but also inhibit cardiomyocyte apoptosis and promote cell survival by modification of MAPK pathways through activating GHS receptor type 1a.
Thyroid Hormone Reduces Cholesterol via a Non-LDL Receptor-Mediated Pathway
Authors: Goldberg Ira J. , Huang Li-Shin , Huggins Lesley A. , Yu Shuiqing , Nagareddy Prabhakara R. , Scanlan Thomas S. , Ehrenkranz Joel R.
Published: September 2012

Although studies in vitro and in hypothyroid animals show that thyroid hormone can, under some circumstances, modulate the actions of low-density lipoprotein (LDL) receptors, the mechanisms responsible for thyroid hormone's lipid-lowering effects are not completely understood. We tested whether LDL receptor (LDLR) expression was required for cholesterol reduction by treating control and LDLR-knockout mice with two forms of thyroid hormone T3 and 3,5-diiodo-l-thyronine. High doses of both 3,5-diiodo-l-thyronine and T3 dramatically reduced circulating total and very low-density lipoprotein/LDL cholesterol (∼70%) and were associated with reduced plasma T4 level. The cholesterol reduction was especially evident in the LDLR-knockout mice. Circulating levels of both apolipoprotein B (apo)B48 and apoB100 were decreased. Surprisingly, this reduction was not associated with increased protein or mRNA expression of the hepatic lipoprotein receptors LDLR-related protein 1 or scavenger receptor-B1. Liver production of apoB was markedly reduced, whereas triglyceride production was increased. Thus, thyroid hormones reduce apoB lipoproteins via a non-LDLR pathway that leads to decreased liver apoB production. This suggests that drugs that operate in a similar manner could be a new therapy for patients with genetic defects in the LDLR.
Positive Youth Development: A Measurement Framework for Sport
Authors: Vierimaa Matthew , Erickson Karl , Côté Jean , Gilbert Wade
Published: September 2012

The 4Cs of positive youth development (PYD; competence, confidence, connection, and character) have been advocated as desirable athlete outcomes of sport participation, and in effect, a useful proxy measure of coaching effectiveness. However, a shortcoming of this framework has been a lack of tangible ways to accurately measure these constructs in athletes. This article reviews the sport literature and presents a concise toolkit made up of existing questionnaires and measurement techniques that can collectively be used to assess coaches' ability to facilitate PYD in athletes in organized youth sport settings. This integrative approach to the measurement of PYD in athletes is not designed to replace similar questionnaires in sport, but is simply a measurement approach grounded in the PYD literature that can be applied across a range of sport contexts. Implications for the use of this framework and toolkit in both coaching research and practice are discussed.
Effect of Low Frequency Burner Vibrations on the Characteristics of Premixed Flames
Authors: Kanthasamy C. , Raghavan Vasudevan , Srinivasan K.
Published: September 2012

Mechanical vibrations in a burner are found to affect the characteristics of premixed flames. In the present experimental investigation, the effects of axial vibrations of a tubular burner on the characteristics of laminar premixed methane-air flames are investigated. The effect of the frequency and amplitude of the burner vibrations on the flame height oscillations are studied. At a low frequency of around 10 Hz, no effect of vibrations on flame characteristics is observed. At frequencies higher than 10 Hz, the amplitude of flame height oscillations is found to increase with increase in both frequency and amplitude of burner vibrations for the range of frequencies and amplitudes considered.
Market Crashes, Correlated Illiquidity, and Portfolio Choice
Authors: Liu Hong , Loewenstein Mark
Published: September 2012

The recent financial crisis highlights the importance of market crashes and the subsequent market illiquidity for optimal portfolio selection. We propose a tractable and flexible portfolio choice model where market crashes can trigger switching into another regime with a different investment opportunity set. We characterize the optimal trading strategy in terms of coupled integro-differential equations and develop a quite general iterative numerical solution procedure. We conduct an extensive analysis of the optimal trading strategy. In contrast to standard portfolio choice models, changes in the investment opportunity set in one regime can affect the optimal trading strategy in another regime even in the absence of transaction costs. In addition, an increase in the expected jump size can increase stock investment even when the expected return remains the same and the volatility increases. Moreover, we show that misestimating the correlation between market crashes and market illiquidity can be costly to investors.

This paper was accepted by Wei Xiong, finance.
Release Time Scheduling and Hub Location for Next-Day Delivery
Authors: Yaman Hande , Karasan Oya Ekin , Kara Bahar Y.
Published: September 2012

Inspired by a real-life problem faced by one of the largest ground-based cargo companies of Turkey, the current study introduces a new facet to the hub location literature. The release time scheduling and hub location problem aims to select a specified number of hubs from a fixed set of demand centers, to allocate each demand center to a hub, and to decide on the release times of trucks from each demand center in such a way that the total amount of cargo guaranteed to be delivered to every potential destination by the next day is not below a threshold and the total routing cost is minimized. The paper introduces integer programming models to solve this problem in the special cases when the cargo uniformly arrives to each demand center during the day and the more realistic pattern of when the cargo arrivals exhibit a piecewise linear form. Several classes of valid inequalities are proposed to strengthen the formulations. Extensions with multiple service levels and discrete sets for release times are also discussed. Computational results show the computational viability of the models under realistic scenarios as well as the validity of the proposed problems in answering several interesting questions from the cargo sector's perspective.
Conditional Value-at-Risk and Average Value-at-Risk: Estimation and Asymptotics
Authors: Chun So Yeon , Shapiro Alexander , Uryasev Stan
Published: September 2012

We discuss linear regression approaches to the estimation of law-invariant conditional risk measures. Two estimation procedures are considered and compared; one is based on residual analysis of the standard least-squares method, and the other is in the spirit of the M-estimation approach used in robust statistics. In particular, value-at-risk and average value-at-risk measures are discussed in detail. Large sample statistical inference of the estimators is derived. Furthermore, finite sample properties of the proposed estimators are investigated and compared with theoretical derivations in an extensive Monte Carlo study. Empirical results on the real data (different financial asset classes) are also provided to illustrate the performance of the estimators.
Mineral Preferred Orientation and Microstructure in the Posidonia Shale in Relation to Different Degrees of Thermal Maturity
Authors: Kanitpanyacharoen Waruntorn , Kets Frans B. , Wenk Hans-Rudolf , Wirth Richard
Published: September 2012

The thermal maturity of samples of the Posidonia Shale collected from the Hils Syncline, northern Germany, varies significantly as a function of location indicating variations in local history. Synchrotron X-ray diffraction was used to document the composition and the preferred orientation of four samples of the Posidonia Shale with different degrees of maturity (0.68–1.45%, Ro) to determine possible effects on diagenesis and preferred orientation. Overall, the degree of preferred orientation of all clay minerals (illite-smectite, illite-mica, and kaolinite) and in all samples is similar, with (001) pole figure maxima ranging from 3.7 to 6.3 multiples of a random distribution (m.r.d.). Calcite displays weak preferred orientation, with c axes perpendicular to the bedding plane (1.1–1.3 m.r.d.). Other constituent phases such as quartz, feldspars, and pyrite have a random orientation distribution. The difference in thermal history, which causes significant changes in the maturity of organic matter, influenced the preferred orientation of clay minerals only marginally as most of the alignment seems to have evolved early in their history. Synchrotron X-ray microtomography was used to characterize the three-dimensional microstructure of a high-maturity sample. Low-density features, including porosity, fractures, and kerogen, were observed to be elongated and aligned roughly parallel to the bedding plane. The volume of low-density features was estimated to be ~7 vol.%, consistent with previous petrophysical measurements of porosity of 8–10 vol.%. Transmission electron microscopy analysis of samples with different degrees of maturity (0.74%Ro and 1.45%Ro) was used to document microstructures at the nanoscale as well as the presence of kerogen. In the high-maturity sample, pores were less abundant while minerals were more deformed as shown by fractured calcite and by kinked and folded illite. Some of the porosity was aligned with clay platelets.
Health, masks and music: Narratives of empowerment in a South African community music therapy project based in a tuberculosis hospital
Authors: Oosthuizen Helen
Published: September 2012

This article introduces the Music Therapy Community Clinic’s (MTCC) Music for Health Project based in a tuberculosis (TB) hospital in South Africa. The value of this community music therapy project is explored from various narrative frameworks pertaining to health and the TB disease.
Initially viewed from a reductionist medical narrative with a primary focus on treatment of physical symptoms, music therapy offers patients a diversion from their illness, but is perhaps a luxury rather than an essential form of therapy. The project is then considered from a narrative framework
of empowerment, placing TB as a disease that predominantly affects those who are disempowered through poverty, stigmatization and isolation. Three case studies explore how community music therapy serves to empower patients on individual and collective levels, and consider possibilities this
may hold for influencing the health behaviour of patients. As TB is becoming a pertinent issue worldwide, the article may offer possibilities for the role of creative approaches in the care of TB patients.
ITRS lithography roadmap: status and challenges
Authors: Neisser Mark , Wurm Stefan
Published: September 2012

Recent ITRS lithography roadmaps show a big technology decision approaching the semiconductor industry about how to do leading edge lithography. The need is rapidly approaching for the industry to select an option for the 22-nm half pitch, but no decision has been made yet. The main options for the 22-nm half pitch are extreme ultraviolet (EUV), ArF immersion lithography with multiple patterning, and maskless lithography. For the 16-nm half pitch, directed self-assembly (DSA) is also an option. The EUV has the most industry investment and is the closest to current lithography in the way it works but still faces challenges in tool productivity and defect-free masks. The nanoimprint needs to overcome the defect, contamination, and overlay challenges before it can be applied to the semiconductor production. Maskless lithography may be used first for prototyping and small volume products where mask costs per chip produced would be very high. Double patterning could be extended to multiple pattering, but would give tremendous process complexity and exponentially rising mask costs due to the many exposures needed per level. The DSA, which only recently has emerged from the research stage, has the potential for very high resolution but represents a huge change in how critical dimensions are formed and controlled.
Rapamycin Delays Disease Onset and Prevents PrP Plaque Deposition in a Mouse Model of Gerstmann–Sträussler–Scheinker Disease
Authors: Cortes Constanza J. , Qin Kefeng , Cook Julie , Solanki Ani , Mastrianni James A.
Published: September 2012

Autophagy is a cell survival response to nutrient deprivation that delivers cellular components to lysosomes for digestion. In recent years, autophagy has also been shown to assist in the degradation of misfolded proteins linked to neurodegenerative disease (Ross and Poirier, 2004). In support of this, rapamycin, an autophagy inducer, improves the phenotype of several animal models of neurodegenerative disease. Our Tg(PrP-A116V) mice model Gerstmann–Sträussler–Scheinker disease (GSS), a genetic prion disease characterized by prominent ataxia and extracellular PrP amyloid plaque deposits in brain (Yang et al., 2009). To determine whether autophagy induction can mitigate the development of GSS, Tg(PrP-A116V) mice were chronically treated with 10 or 20 mg/kg rapamycin intraperitoneally thrice weekly, beginning at 6 weeks of age. We observed a dose-related delay in disease onset, a reduction in symptom severity, and an extension of survival in rapamycin-treated Tg(PrP-A116V) mice. Coincident with this response was an increase in the autophagy-specific marker LC3II, a reduction in insoluble PrP-A116V, and a near-complete absence of PrP amyloid plaques in the brain. An increase in glial cell apoptosis of unclear significance was also detected. These findings suggest autophagy induction enhances elimination of misfolded PrP before its accumulation in plaques. Because ataxia persisted in these mice despite the absence of plaque deposits, our findings also suggest that PrP plaque pathology, a histopathological marker for the diagnosis of GSS, is not essential for the GSS phenotype.
Robo2–Slit and Dcc–Netrin1 Coordinate Neuron Axonal Pathfinding within the Embryonic Axon Tracts
Authors: Zhang Changwen , Gao Jingxia , Zhang Hefei , Sun Liu , Peng Gang
Published: September 2012

In the embryonic vertebrate brain, early born neurons establish highly stereotyped embryonic axonal tracts along which the neuronal interconnections form. To understand the mechanism underlying neuron axonal pathfinding within the embryonic scaffold of axon tracts, we studied zebrafish anterior dorsal telencephalic (ADt) neuron development. While previous studies suggest the ADt neuronal axons extend along a commissural tract [anterior commissure (AC)] and a descending ipsilateral tract [supraoptic tract (SOT)], it is unclear whether individual ADt neuronal axons choose specific projection paths at the intersection between the AC and the SOT. We labeled individual ADt neurons using a forebrain-specific promoter to drive expression of fluorescent proteins. We found the ADt axonal projection patterns were heterogeneous and correlated with their soma positions. Our results suggest that cell intrinsic differences along the dorsal ventral axis of the telencephalon regulate the axonal projection choices. Next, we determined that the guidance receptors roundabout2 (Robo2) and deleted in colorectal cancer (Dcc) were differentially expressed in the ADt neurons. We showed that knocking down Robo2 function by injecting antisense morpholino oligonucleotides abolished the ipsilateral SOT originating from the ADt neurons. Knocking down Dcc function did not prevent formation of the AC and the SOT. In contrast, the AC was specifically reduced when Netrin1 function was knocked down. Further mechanistic studies suggested that Robo2 responded to the repellent Slit signals and suppressed the attractive Netrin signals. These findings demonstrate how Robo2–Slit and Dcc–Netrin coordinate the axonal projection choices of the developing neurons in the vertebrate forebrain.
Synthesis of Novel Lithium Salts containing Pentafluorophenylamido-based Anions and Investigation of their Thermal and Electrochemical Properties
Authors: Huber Benedikt , Linder Thomas , Hormann Kristof , Frömling Till , Sundermeyer Jörg , Roling Bernhard
Published: September 2012

Three novel lithium salts, lithium bis(pentafluorophenyl)amide LiN(Pfp)2, lithium pentafluorphenyl(trifluormethylsulfonyl)imide LiN(Pfp)(Tf) and lithium pentafluorphenyl(nonafluorbutylsulfonyl)imide LiN(Pfp)(Nf) were synthesized and characterized with respect to their thermal and electrochemical properties. LiN(Pfp)2 decomposes at 108 ºC, whereas Li-N(Pfp)(Tf) and Li-N(Pfp)(Nf) show a much higher thermal stability of 307 ºC and 316 ºC, respectively. The ionic conductivity at 100 ºC measured by means of impedance spectroscopy decreases in the order LiN(Pfp)(Tf) > LiN(Tf)2
> LiN(Pfp)(Nf). Both, the activation energy and entropy for ion conduction in the new salts are lower than in LiN(Tf)2 (LiTFSI), most likely due to the lower symmetry of the new anions. The electrochemical stability and ionic conductivity of LiN(Pfp)(Tf) and LiN(Pfp)(Nf) solutions (0.1 mol/l) in ethylene carbonate/dimethyl carbonate (1:3 w/w) are slightly lower than those of the LiTFSI solution, but still sufficient for application in lithium ion batteries. The high thermal stability of the novel salts and their stability towards hydrolysis makes them attractive candidates for overcoming the drawbacks of LiPF6-based electrolytes at elevated temperatures.
Double Responsive Hydrogels based on Tertiary Amine Methacrylate Star Block Copolymers
Authors: Schmalz Alexander , Schmalz Holger , Müller Axel H. E.
Published: September 2012

Double hydrophilic stimuli-responsive star block copolymers with poly(2-(dimethylamino)ethyl methacrylate) (PDMA) inner blocks and poly(2-(diethylamino)ethyl methacrylate) (PDEA) outer blocks were synthesized using ATRP. Different multifunctional initiators based on sugar scaffolds were employed in a core-first approach with sequential polymerization of both blocks yielding stars with 4 and 6 arms, respectively, and varying length of the PDEA outer block. The star block copolymers show pH- and temperature-responsive aggregation as revealed by dynamic light scattering and turbidimetry. The impact of pH, PDEA block length and arm number on the gelation behavior was investigated by tube inversion and rheology.
Solubilisation of Oils of Different Polarity in Aqueous Solutions of Pluronic Triblock Copolymers
Authors: Liu Hsin-Yi , Prévost Sylvain , Gradzielski Michael
Published: September 2012

The micellisation behaviour of Pluronic F108 was studied as a function of the addition of various more or less polar additives, such as hexanol, geraniol, toluene, methyl heptanoate, polyproylene oxide (PPO), and nitropropane. It is observed that the critical micellisation temperature (CMT) is substantially reduced upon the solubilisation of most of the additives (but not for methyl heptanoate and PPO) and at the same time the concomitant enthalpy of micellisation becomes larger. Both changes in CMT and enthalpy of micellisation are linear with respect to the concentration of additive. The pronouncedness of this effect is related to the polarity of the additive (as characterised for instance by its water solubility) and for instance similar effects are achieved for much smaller amounts of geraniol compared to hexanol. The structural evolution of the Pluronic solutions upon addition of the additives was also followed by SANS experiments and show that relatively small amounts of added solubilisate can have a very pronounced effect on the extent of the micellisation and size of the aggregates formed, i.e., effectively lowering the CMT by rendering the amphiphilic system more hydrophobic and especially the medium chain alcohols show pronounced synergism.
Terminology inaccuracies in the interpretation of imaging results in detection of cervical lymph node metastases in papillary thyroid cancer
Authors: Mulla Mubashir , Schulte Klaus-Martin
Published: September 2012

Cervical lymph nodes (CLNs) are the most common site of metastases in papillary thyroid cancer (PTC). Ultrasound scan (US) is the most commonly used imaging modality in the evaluation of CLNs in PTC. Computerised tomography (CT) and 18fluorodeoxyglucose positron emission tomography (18FDG PET–CT) are used less commonly. It is widely believed that the above imaging techniques should guide the surgical approach to the patient with PTC.

Methods

We performed a systematic review of imaging studies from the literature assessing the usefulness for the detection of metastatic CLNs in PTC. We evaluated the author's interpretation of their numeric findings specifically with regard to ‘sensitivity’ and ‘negative predictive value’ (NPV) by comparing their use against standard definitions of these terms in probabilistic statistics.

Results

A total of 16 studies used probabilistic terms to describe the value of US for the detection of LN metastases. Only 6 (37.5%) calculated sensitivity and NPV correctly. For CT, out of the eight studies, only 1 (12.5%) used correct terms to describe analytical results. One study looked at magnetic resonance imaging, while three assessed 18FDG PET–CT, none of which provided correct calculations for sensitivity and NPV.

Conclusion

Imaging provides high specificity for the detection of cervical metastases of PTC. However, sensitivity and NPV are low. The majority of studies reporting on a high sensitivity have not used key terms according to standard definitions of probabilistic statistics. Against common opinion, there is no current evidence that failure to find LN metastases on ultrasound or cross-sectional imaging can be used to guide surgical decision making.
Bioatividade de nanoformulações de nim sobre a traça-do-tomateiro
Authors: Ferreira Fátima Teresinha Rampelotti , Vendramim José Djair , Forim Moacir Rossi
Published: September 2012

O uso de plantas inseticidas é uma importante ferramenta para o manejo de insetos-praga. Visando ao controle de Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), nanoformulações de nim foram avaliadas. Após a estimativa de uma CL50 para uma formulação de óleo comercial de nim, bioensaios de seleção foram realizados com 22 nanoformulações. Para isso, lagartas neonatas foram alimentadas sobre folíolos tratados com soluções das nanoformulações durante 10 dias. Com as duas nanoformulações mais promissoras, NC40 aquoso e NC40 pó (NC 40=nanocápsulas de Poli- β-hidroxibutirato), foi avaliado o efeito sobre o desenvolvimento e a longevidade do inseto. A CL50 para o óleo de nim foi estimada em 0,20% ou 1,31mgL-1 de azadiractina. As nanoformulações NC40 aquoso e NC40 pó afetaram o desenvolvimento do inseto.
Metodologia alternativa para condução do teste de envelhecimento acelerado em sementes de milho
Authors: Bittencourt Sonia Regina Mudrovitsch de , Grzybowski Camila Ribeiro de Souza , Panobianco Maristela , Vieira Roberval Daiton
Published: September 2012

Os testes de vigor são rotineiramente empregados em programas internos de controle de qualidade por empresas sementeiras. Para tanto, é necessária a escolha de métodos eficientes que possibilitem a obtenção de respostas rápidas para a tomada de decisões relacionadas ao manuseio, descarte e comercialização dos lotes de sementes. A pesquisa objetivou verificar a redução do período de execução do teste de envelhecimento acelerado (EA) em sementes de milho, empregando-se, para a avaliação do desempenho das sementes após o envelhecimento, o teste de tetrazólio - TZ (viabilidade e vigor) em substituição ao de germinação (TG) em 10 lotes de sementes de sete genótipos de milho, com e sem tratamento fungicida. Os dados obtidos com a metodologia proposta (EA+TZ) foram comparados com os valores determinados pelo teste de envelhecimento acelerado realizado com a metodologia tradicional (EA+TG). O uso do teste de tetrazólio (vigor), associado ao teste de envelhecimento acelerado, possibilitou a obtenção de informações semelhantes às fornecidas pelo teste de germinação empregado para o mesmo fim, reduzindo de oito para três dias o tempo necessário para a obtenção dos resultados em sementes de milho.
Aplicação de 1-metilciclopropeno, estresse inicial com baixo oxigênio e armazenamento em ultrabaixo oxigênio na qualidade de maçã Fuji
Authors: Brackmann Auri , Gasperin Adriano Roque de , Both Vanderlei , Pavanello Elizandra Pivotto , Schorr Márcio Renan Weber , Anese Rogério de Oliveira
Published: September 2012

O objetivo deste trabalho foi avaliar o efeito da aplicação de 1-MCP em combinação com condições de estresse inicial com baixo O2 e armazenamento em atmosfera controlada com pressões parciais ultrabaixas de O2 sobre a manutenção da qualidade de maçãs Fuji. Os tratamentos avaliados foram com e sem aplicação de 1-MCP (1.000nL L-1), combinado com cinco níveis do fator condição de armazenamento (sem estresse inicial + 0,6kPa O2, 1 estresse + 0,6kPa O2, 1 estresse + 0,8kPa O2, 2 estresses + 0,6kPa O2 e sem estresse inicial + 1,0kPa O2). Cada estresse inicial foi com 0,2kPa de O2 pelo período de 14 dias. Os frutos foram armazenados nessas condições durante oito meses a -0,5°C±0,2°C e UR de 96±1%, mais sete dias de exposição a 20±1°C. Em todos os tratamentos, o CO2 foi mantido abaixo de 0,5kPa. O armazenamento sem estresse inicial por baixo O2 associado a 1,0kPa ou 0,6kPa de O2 manteve a polpa mais firme e com maior acidez titulável. Além disso, proporcionou menor ocorrência de podridão após oito meses de armazenamento mais sete dias a 20°C. O 1-MCP proporcionou menor atividade da enzima ACC oxidase, no entanto, não foi eficiente para a redução da produção de etileno e para retardar a perda da firmeza e a ocorrência de podridão. O estresse inicial de 14 dias com 0,2kPa de O2 prejudicou a conservação de maçãs Fuji.
Perfil lipídico da polpa e amêndoa da guarirova
Authors: Nozaki Vanessa Taís , Munhoz Cláudia Leite , Guimarães Rita de Cássia Avellaneda , Hiane Priscila Aiko , Andreu Maxwell Parrela , Viana Luiz Henrique , Macedo Maria Lígia Rodrigues
Published: September 2012

Os óleos de frutos estão sendo estudados por seu potencial na indústria de alimentos e também para aumento do consumo de ácidos graxos monos e poli-insaturados. Este estudo objetivou determinar as constantes físico-químicas, composição centesimal, identificar e quantificar os principais ácidos graxos presentes na fração lipídica da polpa e da amêndoa dos frutos de guarirova, espécie Syagrus oleracea (Mart.) Becc. Foi realizada a caracterização físico-química dos óleos, composição de ácidos graxos e índices de qualidade nutricional. O óleo da amêndoa possui maior concentração de ácidos graxos saturados (89,2%), sendo representado principalmente pelo ácido láurico (48,34%). A polpa apresentou ácidos graxos monoinsaturados (24,84%) e poli-insaturados (33,25%), com maior percentual de ômega-6 (31,94%) e ômega-9 (19,15%); e menor de ômega-3 (1,31%).
Índice de enfisema pulmonar em coorte de pacientes sem doença pulmonar conhecida: influência da idade
Authors: Hochhegger Bruno , Alves Giordano Rafael Tronco , Irion Klaus Loureiro , Moreira José da Silva , Marchiori Edson dos Santos
Published: September 2012

OBJETIVO: Investigar os efeitos da idade no enfisema pulmonar, com base nos valores do índice de enfisema (IE) em uma coorte de pacientes que nunca fumou e que não possuía doença pulmonar conhecida. MÉTODOS: Foram revisados exames de TC, considerados normais, de 315 pacientes. Tabagismo, doenças cardiorrespiratórias e exposição a drogas que poderiam causar doença pulmonar foram critérios de exclusão. Dessa coorte, selecionamos 32 pacientes (16 homens e 16 mulheres), igualmente divididos em dois grupos (idade < 50 anos e idade > 50 anos), que foram pareados por gênero e índice de massa corpórea. Realizou-se a quantificação do enfisema utilizando um programa específico. O IE foi calculado com um limiar de -950 UH. O volume pulmonar total (VPT) e a densidade pulmonar média (DPM) também foram avaliados. RESULTADOS: As médias gerais de VPT, DPM e IE foram 5.027 mL, -827 UH e 2,54%, respectivamente. A comparação entre os mais velhos e os mais novos mostrou as seguintes médias: VPT, 5.229 mL vs. 4.824 mL (p > 0,05); DPM, -846 UH vs. -813 UH (p < 0,04) e IE, 3,30% vs. 1,28% (p < 0,001). Houve correlações significativas entre IE e idade (r = 0,66; p = 0,001), IE e VPT (r = 0,58; p = 0,001) e IE e DPM (r = -0,67; p < 0,001). O IE previsto por idade foi definido através da equação de regressão (r² = 0,43): p50(IE) = 0,049 × idade - 0,5353. CONCLUSÕES: É importante considerar a influência da idade na quantificação de enfisema em pacientes com mais de 50 anos. Baseado na análise de regressão, valores de IE de 2,6%, 3,5% e 4,5% podem ser considerados normais para pacientes com 30, 50 e 70 anos, respectivamente.
Evolução das políticas públicas e programas de controle da asma no Brasil sob a perspectiva dos consensos
Authors: Amaral Lígia Menezes do , Palma Pamella Valente , Leite Isabel Cristina Gonçalves
Published: September 2012

Percebe-se que muito se discute sobre políticas públicas eficazes que possibilitem o tratamento adequado da asma, oferecendo um atendimento integral e centrado no paciente asmático dentro do seu contexto social. Educar profissionais de saúde e a população de asmáticos possibilita um melhor reconhecimento dos sintomas, dos fatores desencadeantes de exacerbações e das formas para evitá-los, garantindo melhor tratamento e qualidade de vida do paciente. A asma impõe crescente carga à sociedade em termos de redução da qualidade de vida, custos com cuidados de saúde e morbidade. Por isso, torna-se de suma importância sua discussão no campo das políticas públicas.
Occurrence of micro-organic pollutants on phosphorus recovery from urine
Authors: Kemacheevakul P. , Otani S. , Matsuda T. , Shimizu Y.
Published: September 2012

Increased population growth and food prices have resulted in more demand for fertilizers, especially phosphorus (P), to be used in agriculture and production of food crops. Phosphorus is one of the important natural resources and will be exhausted in the near future. Nowadays, struvite production is a good method to recover P from urine. However, the natural urines contain high amounts of micro-organic pollutants which may cause health risks. Therefore, in this contribution, we investigated the amount of micro-organic pollutants in struvite from urine. There are various kinds of pharmaceuticals and hormones which are used in the world. Nevertheless, we focused on 10 pharmaceuticals (amoxycillin, carbamazepine, erythromycin, furosemide, atenolol, ibuprofen, norfloxacin, trimethoprim, tetracycline, and acetylsalicylic acid) and one hormone (17β-estradiol) as representatives. The experiments were carried out with synthetic and natural urines. After the production of struvite, the results from synthetic and natural urine samples showed that only tetracycline, erythromycin, and norfloxacin remained in the struvite, and, especially, tetracycline remained in struvite with quite a high amount.