5-0 Polypropylene versus 5-0 fast absorbing plain gut for cutaneous wound closure: a randomized evaluator blind trial

Mixed opinions exist regarding cosmetic outcomes of 5-0 fast absorbing plain (FG) gut relative to nonabsorbable suture material, such as 5-0 polypropylene (PP). High quality randomized trials comparing these two suture materials are lacking. To determine whether the use of PP during layered repair of linear cutaneous surgery wounds improves scar cosmesis compared to wound closure with FG. A randomized, split wound, comparative effectiveness trial was undertaken. Patients were evaluated 3 months after the intervention by two blinded physicians using the validated patient observer scar assessment scale (POSAS). Patient assessments were also captured using the same instrument as well as scar width and complications. The mean sum of the six components of the POSAS was 10.26 vs 12.74 for PP and FG, respectively, significantly (p < 0.001) in favor of PP. Mean observer overall opinion similarly showed better outcomes for PP than for FG [1.88 vs 2.52, respectively (p < 0.006)]. The mean sum of the patient assessed components of the POSAS for PP and FG was 12.3 vs 14.34, respectively (p = 0.11). Patient overall opinion significantly favored PP (2.41 vs 3.14, p = 0.043). PP resulted in small but statistically significant better cosmetic outcomes than FG. Pain experienced during suture removal was minimal for most patients

Constraining the Origin and Age of the Thermal and Cold Water in the Lake Natron Basin, Northern Tanzania

Springs on the eastern and western shores of Lake Natron Basin (LNB), located within the eastern branch of the East Africa Rift System (EARS) in Northern Tanzania had a discharge temperature that ranged between 34.0 °C and 51.2 °C, while the pH varied from 8.0 to 10.7. The electrical conductivity (EC) ranged between 5,007 µS/cm and 49,200 µS/cm. Cold waters had a temperature of 31.9 °C to 32.5 °C, while the pH ranged between 8.0 and 8.3, and the EC ranged between 1,401 µS/cm and 3,806 µS/cm. The stable isotope composition varied between -2.4 ‰ and -5.3 ‰ for δ18O, and -15.5 ‰ to -29.3 ‰ for δ2H. The isotopic composition of thermal and cold water of LNB indicates a significant contribution of meteoric water in the recharge of the hydrothermal system. However, thermal water is affected by evaporation, water-rock interaction, carbon dioxide (CO2) exchange and condensation processes. Tritium analysis indicated that the spring water in the LNB hydrothermal system has a residence time of more than 50 years. Keywords:    thermal water; Lake Natron Basin; stable isotopes; springs. &nbsp

Interfacial charge transfer in nanoscale polymer transistors

Interfacial charge transfer plays an essential role in establishing the relative alignment of the metal Fermi level and the energy bands of organic semiconductors. While the details remain elusive in many systems, this charge transfer has been inferred in a number of photoemission experiments. We present electronic transport measurements in very short channel ($L < 100$ nm) transistors made from poly(3-hexylthiophene) (P3HT). As channel length is reduced, the evolution of the contact resistance and the zero-gate-voltage conductance are consistent with such charge transfer. Short channel conduction in devices with Pt contacts is greatly enhanced compared to analogous devices with Au contacts, consistent with charge transfer expectations. Alternating current scanning tunneling microscopy (ACSTM) provides further evidence that holes are transferred from Pt into P3HT, while much less charge transfer takes place at the Au/P3HT interface.Comment: 19 preprint pages, 6 figure

Proteins associated with pancreatic cancer survival in patients with resectable pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal disease with a dismal prognosis. However, while most patients die within the first year of diagnosis, very rarely, a few patients can survive for &gt;10 years. Better understanding the molecular characteristics of the pancreatic adenocarcinomas from these very-long-term survivors (VLTS) may provide clues for personalized medicine and improve current pancreatic cancer treatment. To extend our previous investigation, we examined the proteomes of individual pancreas tumor tissues from a group of VLTS patients (survival ≥10 years) and short-term survival patients (STS, survival &lt;14 months). With a given analytical sensitivity, the protein profile of each pancreatic tumor tissue was compared to reveal the proteome alterations that may be associated with pancreatic cancer survival. Pathway analysis of the differential proteins identified suggested that MYC, IGF1R and p53 were the top three upstream regulators for the STS-associated proteins, and VEGFA, APOE and TGFβ-1 were the top three upstream regulators for the VLTS-associated proteins. Immunohistochemistry analysis using an independent cohort of 145 PDAC confirmed that the higher abundance of ribosomal protein S8 (RPS8) and prolargin (PRELP) were correlated with STS and VLTS, respectively. Multivariate Cox analysis indicated that 'High-RPS8 and Low-PRELP' was significantly associated with shorter survival time (HR=2.69, 95% CI 1.46-4.92, P=0.001). In addition, galectin-1, a previously identified protein with its abundance aversely associated with pancreatic cancer survival, was further evaluated for its significance in cancer-associated fibroblasts. Knockdown of galectin-1 in pancreatic cancer-associated fibroblasts dramatically reduced cell migration and invasion. The results from our study suggested that PRELP, LGALS1 and RPS8 might be significant prognostic factors, and RPS8 and LGALS1 could be potential therapeutic targets to improve pancreatic cancer survival if further validated

Symbolic powers of monomial ideals and Cohen-Macaulay vertex-weighted digraphs

In this paper we study irreducible representations and symbolic Rees algebras of monomial ideals. Then we examine edge ideals associated to vertex-weighted oriented graphs. These are digraphs having no oriented cycles of length two with weights on the vertices. For a monomial ideal with no embedded primes we classify the normality of its symbolic Rees algebra in terms of its primary components. If the primary components of a monomial ideal are normal, we present a simple procedure to compute its symbolic Rees algebra using Hilbert bases, and give necessary and sufficient conditions for the equality between its ordinary and symbolic powers. We give an effective characterization of the Cohen--Macaulay vertex-weighted oriented forests. For edge ideals of transitive weighted oriented graphs we show that Alexander duality holds. It is shown that edge ideals of weighted acyclic tournaments are Cohen--Macaulay and satisfy Alexander dualityComment: Special volume dedicated to Professor Antonio Campillo, Springer, to appea

Chandra follow up of the Hectospec Cluster Survey: Comparison of Caustic and Hydrostatic Masses and Constraints on the Hydrostatic Bias

Clusters of galaxies are powerful probes with which to study cosmology and astrophysics. However, for many applications an accurate measurement of a cluster's mass is essential. A systematic underestimate of hydrostatic masses from X-ray observations (the so-called hydrostatic bias) may be responsible for tension between the results of different cosmological measurements. We compare X-ray hydrostatic masses with masses estimated using the caustic method (based on galaxy velocities) in order to explore the systematic uncertainties of both methods and place new constraints on the level of hydrostatic bias. Hydrostatic and caustic mass profiles were determined independently for a sample of 44 clusters based on Chandra observations of clusters from the Hectospec Cluster Survey. This is the largest systematic comparison of its kind. Masses were compared at a standardised radius ($R_{500}$) using a model that includes possible bias and scatter in both mass estimates. The systematics affecting both mass determination methods were explored in detail. The hydrostatic masses were found to be systematically higher than caustic masses on average, and we found evidence that the caustic method increasingly underestimates the mass when fewer galaxies are used to measure the caustics. We limit our analysis to the 14 clusters with the best-sampled caustics where this bias is minimised ($\ge210$ galaxies), and find that the average ratio of hydrostatic to caustic mass at $R_{500}$ is $M_X/M_C=1.12^{+0.11}_{-0.10}$. We interpret this result as a constraint on the level of hydrostatic bias, favouring small or zero levels of hydrostatic bias (less than $20\%$ at the $3\sigma$ level). However, we find systematic uncertainties associated with both mass estimation methods remain at the $10-15\%$ level, which would permit significantly larger levels of hydrostatic bias.Comment: 15 pages plus appendices. Updated to match version accepted for publication in A&A. Updates include additional tests of systematics. Main results are unchange

Primary Nanocrystalline Anhydrous Chondrule Mesostasis: Limited Evidence of Secondary Alteration in Most CR Chondrites

The chondrule regions generally regarded to be most susceptible to aqueous alteration are mesostasis and Fe-Ni metal nodules. In CMs, studies of mesostasis have successfully placed contraints into their asteroidal histories. Unlike CM mesostasis, only a few studies of CR mesostasis are currently available [e.g. 1-4]. Here we study the effects aqueous alteration can have on the texture, composition, and mineralogy of CR chondrule mesostasis from 9 Antarctic CR chondrites: EET 92062,5, EET 96259,13, GRA 95229,77, GRO 95577,61 LAP 02342,44, LAP 04516,4, LAP 04720,16 and MIL 07525,7 and MIL 090001,2, generously provided by the U.S. Antarctic Meteorite Collection. To our knowledge, this is the first detailed TEM and compositional study of differences between chondrule setting in CR mesostasis. Based on these data, we place constraints on the degree to which these CRs record aqueous alteration