Weak Reduction Research Articles

Statin use after esophageal cancer diagnosis and survival: A population based cohort study

BackgroundA recent epidemiological study of esophageal cancer patients concluded statin use post-diagnosis was associated with large (38%) and significant reductions in cancer-specific mortality. We investigated statin use and cancer-specific mortality in a large population-based cohort of esophageal cancer patients. MethodsNewly diagnosed [2009–2012] esophageal cancer patients were identified from the Scottish Cancer Registry and linked with the Prescribing Information System and Scotland Death Records (to January 2015). Time-dependent Cox regression models were used to calculate hazard ratios (HR) for cancer-specific mortality and 95% confidence intervals (CIs) by post-diagnostic statin use (using a 6 month lag to reduce reverse causation) and to adjust these HRs for potential confounders. Results1921 esophageal cancer patients were included in the main analysis, of whom 651 (34%) used statins after diagnosis. There was little evidence of a reduction in esophageal cancer-specific mortality in statin users compared with non-users after diagnosis (adjusted HR=0.93, 95% CI, 0.81, 1.07) and no dose response associations were seen. However, statin users compared with non-users in the year before diagnosis had a weak reduction in esophageal cancer-specific mortality (adjusted HR=0.88, 95% CI, 0.79, 0.99). ConclusionsIn this large population-based esophageal cancer cohort, there was little evidence of a reduction in esophageal cancer-specific mortality with statin use after diagnosis.

Low-light image enhancement using variational optimization-based retinex model

This paper presents an optimization-based low-light image enhancement method using spatially adaptive �������� -norm based Retinex model. The proposed method adaptively enforces the regularization parameter using the spatially adaptive weight map, which is generated using the bright channel prior (BCP) and local variance map. Since the proposed weight map assigns the smaller weight value at the bright and edge region, the proposed method can perform weak noise reduction to preserve the edges and textures. In addition, the simplified version of the proposed method is presented using the FFT and quantized weight values for the application to consumer devices. Experimental results show that the proposed method can provide better enhanced result without the ι2 -norm minimization artifacts at the low computational cost.

The vectorial λ-calculus

We describe a type system for the linear-algebraic λ-calculus. The type system accounts for the linear-algebraic aspects of this extension of λ-calculus: it is able to statically describe the linear combinations of terms that will be obtained when reducing the programs. This gives rise to an original type theory where types, in the same way as terms, can be superposed into linear combinations. We prove that the resulting typed λ-calculus is strongly normalising and features weak subject reduction. Finally, we show how to naturally encode matrices and vectors in this typed calculus.

Recent Evidence of Large-Scale Receding Snow Water Equivalents in the European Alps

Abstract Snow plays a critical role in the water cycle of many mountain regions and heavily populated areas downstream. In this study, changes of snow water equivalent (SWE) time series from long-term stations in five Alpine countries are analyzed. The sites are located between 500 and 3000 m above mean sea level, and the analysis is mainly based on measurement series from 1 February (winter) and 1 April (spring). The investigation was performed over different time periods, including the last six decades. The large majority of the SWE time series demonstrate a reduction in snow mass, which is more pronounced for spring than for winter. The observed SWE decrease is independent of latitude or longitude, despite the different climate regions in the Alpine domain. In contrast to measurement series from other mountain ranges, even the highest sites revealed a decline in spring SWE. A comparison with a 100-yr mass balance series from a glacier in the central Alps demonstrates that the peak SWEs have been on a record-low level since around the beginning of the twenty-first century at high Alpine sites. In the long term, clearly increasing temperatures and a coincident weak reduction in precipitation are the main drivers for the pronounced snow mass loss in the past.

EVALUATION OF THE EFFICACY AND SAFETY OF THE ART REGIMENS CONTAINING LOW DOSES PHOSPHAZID

In 20 patients, treated with regime of ART including phosphazid at a dose of 800 mg/day, his daily dose was reduced to 400 mg. In 19 of 20 patients the phosphazod’ dose reduction was due to the development of adverse events related to therapy. After changing the phosphazid’ daily dose the patients seen during the 1 year. Lowering the phosphazid’ dose did not lead to virological failure of the regime of ART and/ or progression of HIV-infection. On the background of lower doses in almost all patients observed a significant improvement in health- the reduction of weakness, disappearance of nausea and headaches. The analysis of laboratory data through 48 weeks after the change daily dose of the phosphazid also showed improvement in these indicators.

Parameterization of stochastic multiscale triads

Abstract. We discuss applications of a recently developed method for model reduction based on linear response theory of weakly coupled dynamical systems. We apply the weak coupling method to simple stochastic differential equations with slow and fast degrees of freedom. The weak coupling model reduction method results in general in a non-Markovian system; we therefore discuss the Markovianization of the system to allow for straightforward numerical integration. We compare the applied method to the equations obtained through homogenization in the limit of large timescale separation between slow and fast degrees of freedom. We numerically compare the ensemble spread from a fixed initial condition, correlation functions and exit times from a domain. The weak coupling method gives more accurate results in all test cases, albeit with a higher numerical cost.

Ephedrine treatment for autoimmune myasthenia gravis

We studied the effect and safety of ephedrine as add-on treatment for patients with myasthenia gravis with acetylcholine receptor antibodies (AChR MG), who do not sufficiently respond to standard treatment. Four patients with AChR MG were included in a placebo-controlled, double-blind, and randomised, multiple crossover series of n-of-1 trials. Each n-of-1 trial consisted of 3 cycles, in which two 5-day intervention periods were followed by 2 days washout. In each cycle, ephedrine 50 mg daily in 2 doses was compared with placebo in the alternate treatment period. Primary outcome was a change in QMG score. Add-on treatment with ephedrine compared with placebo improved QMG score by 1.0 point (95% confidence interval 0.21–1.79), which was significant for the group of trial patients as well as for the population treatment effect. Ephedrine also showed a significant trial average treatment effect for all secondary outcomes, improving MG Composite by 2.7, MG-ADL by 1.0 and VAS score for muscle strength by 1.1. Adverse events were mild and included palpitations, tremor and restlessness. Although all ECGs were normal, ephedrine prolonged the corrected QT interval. Ephedrine as add-on treatment for myasthenia gravis resulted in a small but consistent reduction of symptoms and weakness in patients with moderate disease severity.

Study on oil–source correlation by analyzing organic geochemistry characteristics: a case study of the Upper Triassic Yanchang Formation in the south of Ordos Basin, China

In the south of the Ordos Basin, the oil source of the Upper Triassic Yanchang Formation is confused all the time, which affects further exploration. In this study, oil sources from the oil layers of Ch6, Ch8 and Ch9 are all analyzed and confirmed. Through their carbon isotope value and biomarkers, characteristics of crude oils from the Yanchang Formation are analyzed. Then, the oil–source relation is discussed, with the source rocks’ features. Finally, the oil–source relation is calculated through cluster analysis. It is believed that the oils from the Yanchang Formation deposit in a similar redox environment, with weak oxidation–weak reduction, and have all entered maturity stage. Ch9 crude oil is more mature than crude oils from Ch6 and Ch8, and has more advanced plants and fewer algae. Gas chromatography (GC) and gas chromatography–mass spectrometry (GC–MS) analysis show that crude oils from Ch6 and Ch8 may come from Ch7, and Ch9 crude oil may not. Cluster analysis displays that crude oils from Ch6 and Ch8 have closer squared Euclidean distance with Ch7 source rocks than Ch9 crude oil does, indicating crude oils from Ch6 and Ch8 stem from Ch7 source rocks. And Ch9 crude oil has rather close squared Euclidean distance with Ch9 source rocks, illustrating Ch9 crude oil may be from Ch9 source rocks. This research may provide the theoretical basis for the next exploration deploy in the south of Ordos Basin.

The Price and Variety Effects of Vertical Mergers

Vertical mergers within a multi-echelon market result in equilibrium price changes, for wholesalers and retailers, alike. They may also impact the product variety that is available to the consumer, i.e., the equilibrium product assortment sold in the market. In this paper, we consider the simultaneous price and variety effects of vertical mergers in a general two-echelon base model, in which an arbitrary number of firms compete at each echelon; each of the upstream suppliers offers one or multiple products to some or all of the retailers or directly to the end consumer. We assume linear price or two-part tariff contracts, with prices selected sequentially, in a sequence of oligopolistic price competitions: the process starts with the firms at the upper echelon, followed by simultaneous price selections by the retailers in the downstream echelon. To assess the impact on product variety, we employ a demand model with the characteristic that, depending on the selected retail prices, a smaller or larger subset of all potential products is sold in the market. For an arbitrary merger of a supplier with a group of retailers, we characterize the post-merger equilibrium behavior and show how the changes of all performance measures of interest, i.e., wholesale and retail price equilibria, product assortment, sales volumes, the firms' profit levels and consumer welfare, can be computed efficiently. When the merger is strictly vertical, i.e., involves a single retailer (organization) with whom the supplier deals on an exclusive basis, we prove that the merger results in a (weak) reduction of all equilibrium prices, along with a (weak) shrinkage of the product assortment.

Statin use and breast cancer survival: a nationwide cohort study in Scotland.

BackgroundPreclinical evidence suggests that statins could delay cancer progression. Previous epidemiological findings have been inconsistent and some have been limited by small sample sizes, as well as certain time-related biases. This study aimed to investigate whether breast cancer patients who were exposed to statins had reduced breast cancer-specific mortality.MethodsWe conducted a retrospective cohort study of 15,140 newly diagnosed invasive breast cancer patients diagnosed from 2009 to 2012 within the Scottish Cancer Registry. Dispensed medication usage was obtained from linkages to the Scottish Prescribing Information System and breast cancer-specific deaths were identified from National Records of Scotland Death Records. Using time-dependent Cox regression models, hazard ratios (HR) and 95 % confidence intervals (CI) were calculated for the association between post-diagnostic exposure to statins (including simvastatin) and breast cancer-specific mortality. Adjustments were made for a range of potential confounders including age at diagnosis, year of diagnosis, cancer stage, grade, cancer treatments received, comorbidities, socioeconomic status and use of aspirin.ResultsA total of 1,190 breast cancer-specific deaths occurred up to January 2015. Overall, after adjustment for potential confounders, there was no evidence of an association between statin use and breast cancer-specific death (adjusted HR 0.93, 95 % CI 0.77, 1.12). No significant associations were observed in dose–response analyses or in analysis of all-cause mortality. For simvastatin use specifically, a weak non-significant reduction in breast cancer-specific mortality was observed compared to non-users (adjusted HR 0.89, 95 % CI 0.73, 1.08). Statin use before diagnosis was weakly associated with a reduction in breast cancer-specific mortality (adjusted HR 0.85, 95 % CI 0.74, 0.98).ConclusionOverall, we found little evidence of a protective association between post-diagnostic statin use and cancer-specific mortality in a large nation-wide cohort of breast cancer patients. These findings will help inform the decision whether to conduct randomised controlled trials of statins as an adjuvant treatment in breast cancer.

The sensitivity of southeastern United States climate to varying irrigation vigor

AbstractFour regional climate model runs centered on the Southeast United States (SEUS) assuming a crop growing season of May through October are irrigated at 25% (IRR25), 50% (IRR50), 75% (IRR75), and 100% (IRR100) of the root zone porosity to assess the sensitivity of the SEUS climate to irrigation. A fifth run, assuming no irrigation (CTL), is used as the basis for comparison. Across all IRR runs, it is found that there is a general reduction in seasonal mean precipitation over the irrigated cells relative to CTL. This manifests as an increase in dry (0–1 mm/d) days and reduction in > 1 mm/d rainfall events. A comparative moisture budget reveals that area‐averaged precipitation over the irrigated cells displays a reduction in precipitation and runoff in IRR100 with a weaker reduction in IRR25. This is despite an increase in vertically integrated moisture convergence and local evaporation. We find that irrigation increases the lower atmospheric stability, which in turn reduces the convective rainfall over the irrigated areas. Seasonally averaged temperatures reduce over irrigated areas, with the intensity of the reduction increasing with irrigation vigor. This is largely attributed to a repartitioning of sensible heat flux into latent heat flux. There is also, however, a small increase of heat flow to deeper soil layers. Precipitation ahead of transient cold fronts is also reduced by irrigation as they pass over irrigated cells, owing to the increased stability in the lower troposphere. The intensity of this precipitation reduction becomes more intense as irrigation vigor increases. Lastly, heat waves in the SEUS are reduced in intensity over irrigated cells.

Binder-Free Anode of Cyclized-PAN Coating Si/SiO x Composite for Lithium Ion Batteries

Silicon and its oxides are attractive anode materials in energy storage devices, because of their high theoretical Li-storage capacities (Si: ~3580 mA h g− 1; SiO: ~2600 mA h g− 1; and SiO2: ~1680 mA h g− 1), low lithiation potential (<0.5 V vs. Li/Li+), low cost and environmental benignity.1,2 These silicon-based anodes can be used both in traditional lithium ion batteries and in more recent Li-S and Li-O2 batteries as a replacement for the dendrite-forming lithium metal anodes.3 Currently, the most critical challenge is to improve their low initial coulombic efficiency and accommodate the structure degradation and instability of the solid-electrolyte interface caused by the large volume change. Here, we propose a binder-free structured Si/SiO x anode that can tackle the above issues. We introduce a unique electrode fabrication technique based on directly encapsulating Si/SiO x particles into cyclized polyacrylonitrile (PAN) frameworks as a monolithic, multi-core, cross-linking composite electrode. In this composite, the micro-nano Si/SiO x particles reduced by high-energy ball-milling SiO act as active materials, and the cyclized PAN serves both as binders and conductive agents. Owing to the high electrochemical activity of Si/SiO x and the good mechanical resiliency of cyclized PAN, this specific composite structure enhances the utilization efficiency of silicon oxides and accommodates its large volume expansion, as well as its good ionic and electronic conductivity. The cyclized-PAN coating Si/SiO x composite exhibits excellent electrochemical properties, including a high initial reversible capacity (2734 mA h g− 1 with 75% coulombic efficiency), excellent cycle stability (988 mA h g− 1 after 100 cycles), and good rate capability (800 mA h g− 1 at 1 A g− 1rate). Because the composite is naturally abundant and shows such excellent electrochemical performance, it is a promising anode candidate material for lithium-ion batteries. The binder-free architectural design also provides an effective way to prepare other monolithic electrode materials for advanced lithium-ion batteries. In Fig. 1A, the composite electrode exhibited a monolithic structure with coarse surface morphology, many Si/SiO x particles were exposed onto the electrode surface, and several cracks were caused by the volume contraction of the PAN’s cyclization. These specific structural properties might guarantee the infiltration of the electrolyte into the bulk electrode, which was beneficial for charge transfer and ion transport. In Fig. 1B, the Raman spectra showed a sharp band at 502 cm− 1 which was attributed to the crystalline Si, indicating that nano-Si were dispersed into silicon oxides matrices, another two bands at 1356 and 1592 cm− 1 were attributed to the D-band (disorder-induced phonon mode) and G-band (graphite band), respectively, of delocalized sp2 π bonds in nitrogen doped carbon. In Fig. 1C, the composite electrode showed a weak reduction peak at 0.52 V, which indicated that the capacity loss results from the formation of SEI, and that the reduction of SiO to Si could be negligible in the composite electrode. This was due to the existence of cyclized PAN layer coating on active materials that hindered the decomposition of the electrolyte, as well as the mechanochemical reduction of SiO to nano-Si oxides could reduce the formation of Li2O and Li-silicates. Fig. 1D showed the charge–discharge profiles of the composite electrode at the current density of 0.1 A g− 1. It delivered a high initial discharge capacity of 2733.7 mA h g− 1 and a charge capacity of 2046.6 mA h g− 1, with 75% coulombic efficiency. The second discharge capacity could maintain at 2051.2 mA h g− 1. After 100 cycles (Fig. 1E), the composite electrode revealed a high capacity retention of 987.8 mA h g− 1, with an average coulombic efficiency of 98.5% for 100 cycles. Note that the cycle performance of the composite electrode was much better than that of the pristine SiO electrode. In summary, a binder-free anode of cyclized-PAN coating Si/SiO x composite was designed, and it exhibited excellent electrochemical properties in lithium ion batteries. This unique structural design would provide new avenues for the rational engineering of electrode materials for advanced lithium ion batteries and other electrochemical devices. References 1 J.-I. Lee and S. Park, Nano Energy, 2013, 2, 146−152. 2 J. Wang, W. Bao, L. Ma, G. Tan, Y. Su, S. Chen, F. Wu, J. Lu and K. Amine, ChemSusChem, 2015, 8, 4073−4080. 3 N. Liu, Z. Lu, J. Zhao, M. T. McDowell, H.-W. Lee, W. Zhao and Y. Cui, Nat. Nanotechnol., 2014, 9, 187–192. Fig. 1 (A) SEM image, (B) Raman spectrum, (C) Cyclic voltammograms, and (D) Charge–discharge profiles of the composite electrode, and (E) Cycle performance of the pristine SiO electrode and composite electrode at a current density of 0.1 A g−1. Figure 1

Promoting Effect of Amino on Enhancing Cycling Performance at Low Temperatures for Li-S Battery Cathodes

Comparing to lots of research on electrical performance at room temperature for lithium-sulfur (Li-S) batteries, the low-temperature behaviors of cathodes is outside the scope of concern. The amino group was reported to be a promising candidate to suppress the shuttle through the effective chemisorptions between amino and polysulfides. Herein, we demonstrate an amino-functionalized carbon materials deriving from polyimide wastes. The prepared sulfur cathode (PI-AC-56) displays better low-temperature cycle performance. As shown in Fig. 1a, an obvious difference of the discharge voltage profiles at the 100th cycle was displayed for two prepared cathodes. In contrast to AC-50 cathode, the typical two-voltage plateaus were displayed for PI-AC-56 cathode at the 100th cycle. As we know, the long-chain polysulfides could easily dissolve into the electrolyte for Li-S battery at room temperature. As reducing the temperature, the viscosity of electrolyte would increase to some extent. And the electrolyte viscosity would further increase following with the dissolution of polysulfide anion to the electrolyte, which would significantly block the migration rate of lithium ion. The further reduction reaction of polysulfides to insolvable discharge products was stemmed. Thus, the low-voltage plateau mainly controlled by the thermodynamics process disappeared for AC-50 electrode and the utilization efficiency of active material also decreased. In reverse, the presence of amino group on surface of carbon material for PI-AC-56 electrode confines the polysulfides dissolution to the electrolyte by the favourable interactions between polysulfides and amino group, which prevents the further increase of electrolyte viscosity to ensure an appropriate migration rate of lithium ion. This insured further reduction reaction for long-chain discharge products. On the other hand, the amino group also insured a homogenous distribution of insoluble discharge products due to the strong interaction between unpaired electrons in the N atom and Li+ in the Li2S, which can prevent the formation of electrochemically inactive large agglomerates. As shown in Fig. 1b, with comparation of AC-50 cathode, better cycle performance and capacity retention were also achieved for PI-AC-56 electrode. The capacity of 368 mAh g-1 after 100 cycles was retained from PI-AC-56 cathode, which was better than the only capacity of 115 mAh g-1 for AC-50 cathode. And with the increase of cycle numbers, the discharge capacity increased gradually first and then decreased, indicating that an activation process was necessary for PI-AC-56 electrode. CVs results of PI-AC-56 electrode only show a strong reduction peak at 2.31 V (vs Li/Li+) before cycle (Fig. 1c), which was also attributed to the transformation from elemental sulfur (S8) to long-chain lithium polysulfides. In addition to the weak reduction peaks at 2.11 V (vs Li/Li+), another weak reduction peak was observed at about 1.7 V (vs Li/Li+). These two peaks were corresponding to the further reduction reaction of long-chain polysulfides. The similar phenomenon was also obtained for AC-50 cathode at the initial cycle. The difference between the first reduction peak and oxidation peak for PI-AC-56 was smaller than that of AC-50 cathode, indicating the smaller electrode polar for PI-AC-56 electrode. After 100 cycles, an obvious difference was displayed from the CVs curves. A new strong reduction peak relate to the further polysulfide reduction at 1.96 V (vs Li/Li+) appeared for PI-AC-56 electrode, which was corresponding to the presence of low-voltage plateau. Although the similar results also were displayed for AC-50 electrode (Fig. 1d), the whole peak intensity of AC-50 was smaller than that of PI-AC-56 electrode. This result also revealed a fact that the total cell resistance of PI-AC-56 electrode was significantly smaller comparing to AC-50 cathode. These results confirm the positive effect of amino group on improving cycle performance by restricting dissolution of polysulfide to the electrolyte. The electron-donating effect of amino group is favourable to enhancing the reactivity of aromatic carbon rings for sulfur loading by the formation of ammonium polysulphides. Additionally, the lone-pair electrons denoted by the amino group could interact with lithium sulphides by coordination with Li atom. Working together, better cycle performance at different temperatures was achieved by the amino-functionalization. Figure 1

Chemically stable and reusable nano zero-valent iron/graphite-like carbon nitride nanohybrid for efficient photocatalytic treatment of Cr(VI) and rhodamine B under visible light

Graphite-like carbon nitride (g-C3N4) displays strong potential applications in visible-light photocatalytic for water treatment, but its applications are greatly restricted by high recombination probability of photo-generated electron-hole pairs, as well as a weak reduction ability toward the heavy metals. In this work, we reported the synthesis of nZVI-g-C3N4 nano-hybrid with highly efficiency toward the photodegradation of RhB and Cr(VI) under the visible light irradiation. The nZVI nanoparticles can well be immobilized and dispersed on the surface of g-C3N4 nanosheets by a facile borohydride-reduction method. As-synthesized nZVI-g-C3N4 has an improved photocatalytic activity much better than that of the pure g-C3N4, wherein over 92.9% of Cr(VI) and 99.9% of RhB can be removed by using nZVI-g-C3N4. The nZVI particles not only contributes to the reduction and immobilization of Cr(VI), but also accelerates the photocatalytic degradation efficiency of RhB due to a lower recombination rate of photoexcited holes and electrons. Moreover, nZVI-g-C3N4 preserves superior photodegradation efficiency after five experimental cycles. It can be attributed that nZVI-g-C3N4 photocatalyst is chemically stable, and part of nZVI can be recovered by g-C3N4. We believe that, the composite of nZVI-g-C3N4 reported here could provide guidance for the design of efficient and reusable materials to remove both the organic compounds and heavy metal ions from waste waters.

Improved SMB speckle filtering of polarimetric SAR data with synergistic use of orientation angle compensation and spatial majority rule

The scattering-model-based (SMB) speckle filtering for polarimetric SAR (PolSAR) data is reasonably effective in preserving dominant scattering mechanisms. However, the efficiency strongly depends on the accuracies of both the decomposition and classification of the scattering properties. In addition, a relatively weak speckle reduction particularly in distributed media was reported in the related literatures. In this work, an improved SMB filtering strategy is proposed considering the aforementioned deficiencies. First, the orientation angle compensation is incorporated into the SMB filtering process to remedy the overestimation of the volume scattering contribution in the Freeman-Durden decomposition. In addition, an algorithm to select the homogenous pixels is developed based on the spatial majority rule for adaptive speckle reduction. We demonstrate the superiority of the proposed methods in terms of scattering property preservation and speckle noise reduction using L-band PolSAR data sets of San Francisco that were acquired by the NASA/JPL airborne SAR (AIRSAR) system.

The SWI/SNF chromatin remodeling complex exerts both negative and positive control over LET-23/EGFR-dependent vulval induction in Caenorhabditis elegans

Signaling by the epidermal growth factor receptor (EGFR) generates diverse developmental patterns. This requires precise control over the location and intensity of signaling. Elucidation of these regulatory mechanisms is important for understanding development and disease pathogenesis. In Caenorhabditis elegans, LIN-3/EGF induces vulval formation in the mid-body, which requires LET-23/EGFR activation only in P6.p, the vulval progenitor nearest the LIN-3 source. To identify mechanisms regulating this signaling pattern, we screened for mutations that cooperate with a let-23 gain-of-function allele to cause ectopic vulval induction. Here, we describe a dominant gain-of-function mutation in swsn-4, a component of SWI/SNF chromatin remodeling complexes. Loss-of-function mutations in multiple SWI/SNF components reveal that weak reduction in SWI/SNF activity causes ectopic vulval induction, while stronger reduction prevents adoption of vulval fates, a phenomenon also observed with increasing loss of LET-23 activity. High levels of LET-23 expression in P6.p are thought to locally sequester LIN-3, thereby preventing ectopic vulval induction, with slight reductions in its expression interfering with LIN-3 sequestration, but not vulval fate signaling. We find that SWI/SNF positively regulates LET-23 expression in P6.p descendants, providing an explanation for the similarities between let-23 and SWI/SNF mutant phenotypes. However, SWI/SNF regulation of LET-23 expression is cell-specific, with SWI/SNF repressing its expression in the ALA neuron. The swsn-4 gain-of-function mutation affects the PTH domain, and provides the first evidence that its auto-inhibitory function in yeast Sth1p is conserved in metazoan chromatin remodelers. Finally, our work supports broad use of SWI/SNF in regulating EGFR signaling during development, and suggests that dominant SWI/SNF mutations in certain human congenital anomaly syndromes may be gain-of-functions.

The influence of different sample preparation procedures on the determination of fatty acid profiles of beef subcutaneous fat, liver and muscle by gas chromatography

Three sample preparation procedures for producing a solution of fatty acid methyl esters (FAME) from the liver, subcutaneous fat and muscle of 9 bulls were compared. Fat was extracted from fresh samples using solvents under ambient (Folch) or high temperature and pressure (ASE) conditions. As an alternative to Folch, a one-step procedure carried out on freeze-dried samples (Jenkins) was used to produce FAME solutions. All methods involved mild acid-base transmethylation and in each case 9 samples of each tissue type were analyzed in duplicate, resulting in the quantification of 77 FAs. Equal amounts of total FAs were extracted with the different methods. The effect of the method on the FA profile was low in fat, intermediate in liver, and high in muscle. Compared with Folch, ASE resulted in higher saturated and monounsaturated FAs and fewer polyunsaturated FAs (PUFAs), and a lower relative incidence of conjugated linoleic acids (CLA) in muscle (>25%) and liver (17%). Jenkins had a smaller influence than Folch on PUFAs, and caused only a weak reduction in CLA (<3.4%). ASE tended to cause greater oxidation of PUFAs and unacceptable alterations to CLAs compared with Folch. The Jenkins procedure is a valid alternative to Folch when freeze-drying of samples is appropriate.

ChemInform Abstract: Pd@Pt Core-Shell Nanoparticles with Branched Dandelion-Like Morphology as Highly Efficient Catalysts for Olefin Reduction.

A facile synthesis based on the addition of ascorbic acid to a mixture of Na2 PdCl4, K2 PtCl6, and Pluronic P123 results in highly branched core-shell nanoparticles (NPs) with a micro-mesoporous dandelion-like morphology comprising Pd core and Pt shell. The slow reduction kinetics associated with the use of ascorbic acid as a weak reductant and suitable Pd/Pt atomic ratio (1:1) play a principal role in the formation mechanism of such branched Pd@Pt core-shell NPs, which differs from the traditional seed-mediated growth. The catalyst efficiently achieves the reduction of a variety of olefins in good to excellent yields. Importantly, higher catalytic efficiency of dandelion-like Pd@Pt core-shell NPs was observed for the olefin reduction than commercially available Pt black, Pd NPs, and physically admixed Pt black and Pd NPs. This superior catalytic behavior is not only due to larger surface area and synergistic effects but also to the unique micro-mesoporous structure with significant contribution of mesopores with sizes of several tens of nanometers.

Deposition of silver nanoparticles on polyester fiber under ultrasound irradiations

The polyester fiber containing Ag nanoparticles was prepared through the chemical reduction under ultrasound irradiation. Influences of reduction reagents on the morphological properties of Ag nanoparticles@polyester fiber were studied. The sizes of metallic nanoparticles vary significantly with the types of reduction reagents used in the synthesis. A strong reduction reaction promotes a fast reaction rate and favors the formation of smaller nanoparticle. A weak reduction reagent induces a slow reaction rate and favors relatively larger particles. The products were investigated by means of scanning electron microscopy (SEM) and X-ray powder diffraction (XRPD).

Neuroactivity of detonation nanodiamonds: dose-dependent changes in transporter-mediated uptake and ambient level of excitatory/inhibitory neurotransmitters in brain nerve terminals.

BackgroundNanodiamonds are one of the most perspective nano-sized particles with superb physical and chemical properties, which are mainly composed of carbon sp3 structures in the core with sp2 and disorder/defect carbons on the surface. The research team recently demonstrated neuromodulatory properties of carbon nanodots with other than nanodiamonds hybridization types, i.e., sp2 hybridized graphene islands and diamond-like sp3 hybridized elements.ResultsIn this study, neuroactive properties of uncoated nanodiamonds produced by detonation synthesis were assessed basing on their effects on transporter-mediated uptake and the ambient level of excitatory and inhibitory neurotransmitters, glutamate and γ-aminobutyric acid (GABA), in isolated rat brain nerve terminals. It was shown that nanodiamonds in a dose-dependent manner attenuated the initial velocity of Na+-dependent transporter-mediated uptake and accumulation of l-[14C]glutamate and [3H]GABA by nerve terminals and increased the ambient level of these neurotransmitters. Also, nanodiamonds caused a weak reduction in acidification of synaptic vesicles and depolarization of the plasma membrane of nerve terminals.ConclusionsTherefore, despite different types of hybridization in nanodiamonds and carbon dots, they exhibit very similar effects on glutamate and GABA transport in nerve terminals and this common feature of both nanoparticles is presumably associated with their nanoscale size. Observed neuroactive properties of pure nanodiamonds can be used in neurotheranostics for simultaneous labeling/visualization of nerve terminals and modulation of key processes of glutamate- and GABAergic neurotransmission. In comparison with carbon dots, wider medical application involving hypo/hyperthermia, external magnetic fields, and radiolabel techniques can be perspective for nanodiamonds.