Carbon-fiber tips for scanning probe microscopes and molecular electronics experiments

We fabricate and characterize carbon-fiber tips for their use in combined scanning tunneling and force microscopy based on piezoelectric quartz tuning fork force sensors. An electrochemical fabrication procedure to etch the tips is used to yield reproducible sub-100-nm apex. We also study electron transport through single-molecule junctions formed by a single octanethiol molecule bonded by the thiol anchoring group to a gold electrode and linked to a carbon tip by the methyl group. We observe the presence of conductance plateaus during the stretching of the molecular bridge, which is the signature of the formation of a molecular junction.Comment: Conference Proceeding (Trends in NanoTechnology 2011, Tenerife SPAIN); Nanoscale Research Letters, (2012) 7:25

Reliability and reproductibility of skin temperature of overweight subjects by an infrared thermograpy software designed for human beings

The technical improvement and new applications of Infrared Thermography (IRT) with healthy subjects should be accompanied by results about the reproducibility of IRT measurements in different popula-tion groups. In addition, there is a remarkable necessity of a larger supply on software to analyze IRT images of human beings. Therefore, the objectives of this study were: firstly, to investigate the reproducibility of skin temperature (Tsk) on overweight and obese subjects using IRT in different Regions of Interest (ROI), moments and side-to-side differences (?T); and secondly, to check the reliability of a new software called Termotracker®, specialized on the analysis of IRT images of human beings. Methods: 22 overweight and obese males (11) and females (11) (age: 41,51±7,76 years; height: 1,65±0,09 m; weight: 82,41±11,81 Kg; BMI: 30,17±2,58 kg/m²) were assessed in two consecutive thermograms (5 seconds in-between) by the same observer, using an infrared camera (FLIR T335, Sweden) to get 4 IRT images from the whole body. 11 ROI were selected using Termotracker® to analyze its reproducibility and reliability through Intra-class Correlation Coefficient (ICC) and Coefficient of Variation (CV) values. Results: The reproducibility of the side-to-side differences (?T) between two consecutive thermograms was very high in all ROIs (Mean ICC = 0,989), and excellent between two computers (Mean ICC = 0,998). The re-liability of the software was very high in all the ROIs (Mean ICC = 0,999). Intraexaminer reliability analysing the same subjects in two consecutive thermograms was also very high (Mean ICC = 0,997). CV values of the different ROIs were around 2%. Conclusions: Skin temperature on overweight subjects had an excellent reproducibility for consecutive ther-mograms. The reproducibility of thermal asymmetries (?T) was also good but it had the influence of several factors that should be further investigated. Termotracker® reached excellent reliability results and it is a relia-ble and objective software to analyse IRT images of humans beings

Total and high molecular weight adiponectin have similar utility for the identification of insulin resistance

<p>Abstract</p> <p>Background</p> <p>Insulin resistance (IR) and related metabolic disturbances are characterized by low levels of adiponectin. High molecular weight adiponectin (HMWA) is considered the active form of adiponectin and a better marker of IR than total adiponectin. The objective of this study is to compare the utility of total adiponectin, HMWA and the HMWA/total adiponectin index (S_Aindex) for the identification of IR and related metabolic conditions.</p> <p>Methods</p> <p>A cross-sectional analysis was performed in a group of ambulatory subjects, aged 20 to 70 years, in Mexico City. Areas under the receiver operator characteristic (ROC) curve for total, HMWA and the S_Aindex were plotted for the identification of metabolic disturbances. Sensitivity and specificity, positive and negative predictive values, and accuracy for the identification of IR were calculated.</p> <p>Results</p> <p>The study included 101 men and 168 women. The areas under the ROC curve for total and HMWA for the identification of IR (0.664 <it>vs</it>. 0.669, <it>P </it>= 0.74), obesity (0.592 <it>vs</it>. 0.610, <it>P </it>= 0.32), hypertriglyceridemia (0.661 <it>vs</it>. 0.671, <it>P </it>= 0.50) and hypoalphalipoproteinemia (0.624 <it>vs</it>. 0.633, <it>P </it>= 0.58) were similar. A total adiponectin level of 8.03 μg/ml was associated with a sensitivity of 57.6%, a specificity of 65.9%, a positive predictive value of 50.0%, a negative predictive value of 72.4%, and an accuracy of 62.7% for the diagnosis of IR. The corresponding figures for a HMWA value of 4.25 μg/dl were 59.6%, 67.1%, 51.8%, 73.7% and 64.2%.</p> <p>The area under the ROC curve of the S_Aindex for the identification of IR was 0.622 [95% CI 0.554-0.691], obesity 0.613 [95% CI 0.536-0.689], hypertriglyceridemia 0.616 [95% CI 0.549-0.683], and hypoalphalipoproteinemia 0.606 [95% CI 0.535-0.677].</p> <p>Conclusions</p> <p>Total adiponectin, HMWA and the S_Aindex had similar utility for the identification of IR and metabolic disturbances.</p

Histological and Immunohistochemical Evaluation of the Efficacy of a New Cosmetic Formulation in the Treatment of Skin Photoaging

Objective. Mechanism of action of cosmetic products is not often studied. The aim of this study is to determine the histological, immunohistochemical, and clinical changes of a new cosmetic formulation. Methods. Prospective, single-blind, patient-controlled, randomized study in 10 volunteers with mild to moderate skin photoaging on the back of their hands. The product was applied on one hand and a standard cream on the other hand, twice a day for three months. Standardized photographs were taken on basal (T0) and final visit (T1) and skin biopsies were performed. Changes on histological and immunohistochemical markers were studied. Subjective clinical changes were determined. Results. After treatment, a 26.3% improvement on epidermal thickness was detected and a significant increase on collagens I and III, elastin, and fibronectin fibers was achieved (p<0.05). As the expression of MMPs remained stable, this improvement of dermal matrix was attributed to the stimulation of their synthesis. A significant clinical improvement on the treated hand was obtained, compared to control hand. Conclusion. This new cosmetic product with combination of three registered technologies (IFC-CAF, WGC, and RetinSphere), focused on regenerating dermal matrix and activating proliferation of skin cells, has shown to be efficient in the reversion of skin photoaging

Taxonomic variations in the gut microbiome of gout patients with and without tophi might have a functional impact on urate metabolism

Objective: To evaluate the taxonomic composition of the gut microbiome in gout patients with and without tophi formation, and predict bacterial functions that might have an impact on urate metabolism. Methods: Hypervariable V3–V4 regions of the bacterial 16S rRNA gene from fecal samples of gout patients with and without tophi (n=33 and n=25, respectively) were sequenced and compared to fecal samples from 53 healthy controls. We explored predictive functional profles using bioinformatics in order to identify diferences in taxonomy and metabolic pathways. Results: We identifed a microbiome characterized by the lowest richness and a higher abundance of Phascolarctobacterium, Bacteroides, Akkermansia, and Ruminococcus_gnavus_group genera in patients with gout without tophi when compared to controls. The Proteobacteria phylum and the Escherichia-Shigella genus were more abundant in patients with tophaceous gout than in controls. Fold change analysis detected nine genera enriched in healthy controls compared to gout groups (Bifdobacterium, Butyricicoccus, Oscillobacter, Ruminococcaceae_UCG_010, Lachnospiraceae_ND2007_group, Haemophilus, Ruminococcus_1, Clostridium_sensu_stricto_1, and Ruminococcaceae_ UGC_013). We found that the core microbiota of both gout groups shared Bacteroides caccae, Bacteroides stercoris ATCC 43183, and Bacteroides coprocola DSM 17136. These bacteria might perform functions linked to one-carbon metabo‑ lism, nucleotide binding, amino acid biosynthesis, and purine biosynthesis. Finally, we observed diferences in key bacterial enzymes involved in urate synthesis, degradation, and elimination. Conclusion: Our fndings revealed that taxonomic variations in the gut microbiome of gout patients with and with‑ out tophi might have a functional impact on urate metabolism. Keywords: Gout, Gut microbiota, Uric acid metabolis

Clash of Titans: A MUSE dynamical study of the extreme cluster merger SPT-CL J0307-6225

We present MUSE spectroscopy, Megacam imaging, and Chandra X-ray emission for SPT-CL J0307-6225, a z = 0.58 major merging galaxy cluster with a large BCG-SZ centroid separation and a highly disturbed X-ray morphology. The galaxy density distribution shows two main overdensities with separations of 0.144 and 0.017 arcmin to their respective BCGs. We characterize the central regions of the two colliding structures, namely 0307-6225N and 0307-6225S, finding velocity derived masses of M200, N = 2.44 ± 1.41 × 1014M⊙ and M200, S = 3.16 ± 1.88 × 1014M⊙, with a line-of-sight velocity difference of |Δv| = 342 km s-1. The total dynamically derived mass is consistent with the SZ derived mass of 7.63 h70-1 ± 1.36 × 1014M⊙. We model the merger using the Monte Carlo Merger Analysis Code, estimating a merging angle of 36+14-12 ° with respect to the plane of the sky. Comparing with simulations of a merging system with a mass ratio of 1:3, we find that the best scenario is that of an ongoing merger that began 0.96+0.31-0.18 Gyr ago. We also characterize the galaxy population using Hδand [O ii] λ3727 Å lines. We find that most of the emission-line galaxies belong to 0307-6225S, close to the X-ray peak position with a third of them corresponding to red-cluster sequence galaxies, and the rest to blue galaxies with velocities consistent with recent periods of accretion. Moreover, we suggest that 0307-6225S suffered a previous merger, evidenced through the two equally bright BCGs at the centre with a velocity difference of ∼674 km s-1

Planck pre-launch status: Low Frequency Instrument calibration and expected scientific performance

We give the calibration and scientific performance parameters of the Planck Low Frequency Instrument (LFI) measured during the ground cryogenic test campaign. These parameters characterise the instrument response and constitute our best pre-launch knowledge of the LFI scientific performance. The LFI shows excellent $1/f$ stability and rejection of instrumental systematic effects; measured noise performance shows that LFI is the most sensitive instrument of its kind. The set of measured calibration parameters will be updated during flight operations through the end of the mission.Comment: Accepted for publications in Astronomy and Astrophysics. Astronomy & Astrophysics, 2010 (acceptance date: 12 Jan 2010

Precise measurement of the W-boson mass with the CDF II detector

We have measured the W-boson mass MW using data corresponding to 2.2/fb of integrated luminosity collected in proton-antiproton collisions at 1.96 TeV with the CDF II detector at the Fermilab Tevatron collider. Samples consisting of 470126 W->enu candidates and 624708 W->munu candidates yield the measurement MW = 80387 +- 12 (stat) +- 15 (syst) = 80387 +- 19 MeV. This is the most precise measurement of the W-boson mass to date and significantly exceeds the precision of all previous measurements combined

Evidence for t\bar{t}\gamma Production and Measurement of \sigma_t\bar{t}\gamma / \sigma_t\bar{t}

Using data corresponding to 6.0/fb of ppbar collisions at sqrt(s) = 1.96 TeV collected by the CDF II detector, we present a cross section measurement of top-quark pair production with an additional radiated photon. The events are selected by looking for a lepton, a photon, significant transverse momentum imbalance, large total transverse energy, and three or more jets, with at least one identified as containing a b quark. The ttbar+photon sample requires the photon to have 10 GeV or more of transverse energy, and to be in the central region. Using an event selection optimized for the ttbar+photon candidate sample we measure the production cross section of, and the ratio of cross sections of the two samples. Control samples in the dilepton+photon and lepton+photon+\met, channels are constructed to aid in decay product identification and background measurements. We observe 30 ttbar+photon candidate events compared to the standard model expectation of 26.9 +/- 3.4 events. We measure the ttbar+photon cross section to be 0.18+0.08 pb, and the ratio of the cross section of ttbar+photon to ttbar to be 0.024 +/- 0.009. Assuming no ttbar+photon production, we observe a probability of 0.0015 of the background events alone producing 30 events or more, corresponding to 3.0 standard deviations.Comment: 9 pages, 3 figure