Ablation observations for 2008–2011 from the Programme for Monitoring of the Greenland Ice Sheet (PROMICE)

Recent estimates from the glaciological community agree that the Greenland ice sheet is losing mass at an accelerated pace due to climate change (Velicogna 2009; Khan et al. 2010; Rignot et al. 2011). This has caught the attention of the public and policy makers due to the potential impact on sea-level rise (Dahl-Jensen et al. 2009). The mass loss can be attributed approximately equally to increases in meltwater runoff from surface melt and iceberg production (van den Broeke et al. 2009)

The Raman spectra of serine and 3,3-dideutero-serine in aqueous solution

The Raman spectra of serine [[alpha]-amino-[beta]-hydroxypropionic acid; HOCH2CH(NH3)+COO-] and 3,3-dideutero-serine [HOCD2CH(NH3)+COO-] in aqueous solution were studied in the range 4000-300 cm-1. The data obtained for the deuterated compound are novel and provide compelling evidence that previously reported assignments for the undeuterated amino acid should be revised.http://www.sciencedirect.com/science/article/B6THW-4KNMB16-1/1/19da7b30f32b5efeacb053228a66c4a

Intrinsic electric field effects on few-particle interactions in coupled GaN quantum dots

We study the multiexciton optical spectrum of vertically coupled GaN/AlN quantum dots with a realistic three-dimensional direct-diagonalization approach for the description of few-particle Coulomb-correlated states. We present a detailed analysis of the fundamental properties of few-particle/ exciton interactions peculiar of nitride materials. The giant intrinsic electric fields and the high electron/ hole effective masses give rise to different effects compared to GaAs-based quantum dots: intrinsic exciton-exciton coupling, non molecular character of coupled dot exciton wave function, strong dependence of the oscillator strength on the dot height, large ground-state energy shift for dots separated by different barriers. Some of these effects make GaN/AlN quantum dots interesting candidates in quantum information processing

A ’feasibility space’ as a goal to be achieved in the development of new technologies for converting renewable energies

This method article proposes the establishment of a feasibility space as an objective to be achieved during the development of new technologies to convert energy from renewable resources. The feasibility space can also be a reference when designing an energy system based on renewable resources. The feasibility space is a set of parameter values for the design stage that define the economic and technical feasibility of an energy system or a new technology, which must be satisfied when the energy system comes into operation or when the new technology for converting power goes into operation. The study of possible feasibility spaces allows characterizing energy systems or new technologies as attractive investments, or on the other hand, as unfeasible ventures. - The method proposes to establish a goal to achieve during the development of technologies for energy conversion. - The method provides a benchmark for both the stages of design and development of generation systems and new technologies. - The feasibility space constitutes a planning tool for power systems based on renewable resources of any size

Infrared and Raman spectroscopic characterization of the hydrogen-bonding network in l-serine crystal

The IR spectra (4000-400 cm-1) of neat and isotopically substituted (ND/OD <= 10% D and [congruent with]30% D) polycrystalline l-serine ([alpha]-amino-[beta]-hydroxypropionic acid; HO-CH2-CH(NH3)+-COO-) were recorded in the temperature range 300-10 K and assigned. The isotopic-doping/low-temperature methodology, which allows for decoupling of individual proton vibrational modes from the crystal bulk vibrations, was used for estimating the lengths and energies of the different H-bonds present in l-serine crystal. To this end, the frequency shifts observed in both the NH/OH stretching and out-of-plane bending spectral regions (relatively to reference values for these vibrations in non-hydrogen-bonded l-serine molecules) were used, together with previously developed empirical correlations between these spectral parameters and the H-bond properties. In addition, the room-temperature Raman spectrum (4000-150 cm-1) of a single crystal of neat l-serine was also recorded and interpreted. A systematic comparison was made between the spectroscopic data obtained currently for l-serine and previously for dl-serine, revealing that the vibrational spectra of the two crystals reflect well the different characteristics of their hydrogen-bond networks, and also correlate accurately with the different susceptibility of the two crystals to pressure-induced strain.http://www.sciencedirect.com/science/article/B6THW-4K4WMR3-2/1/211ac428c09ebc9eb45cf3b81d93fcb

Programme for Monitoring of the Greenland Ice Sheet (PROMICE): first temperature and ablation records

The Greenland ice sheet is reacting to climate change. Yet, mass-budget estimates differ considerably, partly due to climatic variability and partly to uncertainties in the techniques of assessing mass change (IPCC 2007). Nevertheless, all recent estimates agree that the ice sheet is losing mass (e.g. 286 Gt/yr; Velicogna 2009) at an accelerating rate (Rignot et al. 2011). On top of this, the area with a negative mass budget is expanding rapidly (Khan et al. 2010). The mass loss is attributed equally to increases in both iceberg production and melting of the ice sheet (Van den Broeke et al. 2009). The increasing mass loss in recent years has caught public attention and given rise to concern worldwide due to its potential impact on sea level. In the light of this, the Programme for Monitoring of the Greenland Ice Sheet (PROMICE) was initiated in 2007 (Ahlstrøm &amp; PROMICE project team 2008), lead by the Geological Survey of Denmark and Greenland (GEUS). PROMICE undertakes surface mass-budget measurements using automatic weather stations, quantifies the mass loss by iceberg calving using remotely sensed data from satellites and airborne surveys and tracks changes in the extent of glaciers. In this paper, we focus on weather station measurements, which are crucial in calculating the energy exchange between the atmosphere and the ice sheet, and in validating model calculations of the surface mass budget. In particular, we present the observed temperatures and investigate how their high 2010 values affected ablation in southern Greenlan

Retrofitting unreinforced masonry by steel fiber reinforced mortar coating: uniaxial and diagonal compression tests

AbstractThin layers of mortar reinforced with steel fibers can be applied on one or both sides of bearing walls as an effective seismic strengthening of existing masonry buildings. To assess the effectiveness of this technique, an experimental study on masonry sub-assemblages was carried out at the University of Brescia. This paper summarizes and discusses the main results of the investigation, which included mechanical characterization tests on masonry and its components as well as on the Steel Fiber Reinforced Mortar (SFRM) used to retrofit the masonry samples. Uniaxial and diagonal compression tests were carried out on both unstrengthened wallets and masonry samples retrofitted with 25 mm thick SFRM coating. Both single-sided and double-sided retrofitting configurations for application on wall surfaces were considered. The results highlighted the ability of the technique to improve the compressive and the shear behavior of masonry, even in case of single-sided strengthening. Moreover, no premature debonding of coating was observed. Lastly, the manuscript presents the results of a numerical investigation that was performed both to simulate the diagonal compression tests described in the first part of the paper and to predict the response of panels with different strengthening configurations

Oncological safety of stromal vascular fraction enriched fat grafting in two-stage breast reconstruction after nipple sparing mastectomy: long-term results of a prospective study

OBJECTIVE: Autologous fat transfer (AFT) is commonly used to treat implant palpability and prevent fibrosis and thinning in mastectomy skin flaps. A major limit to this procedure is volume retention over time, leading to the introduction of fat enrichment with stromal vascular fraction (SVF+AFT). Oncological concerns have been raised over the injection of an increased concentration of progenitors cells (ASCs) in the SVF. The aim of the study is to evaluate the long-term cancer recurrence risk of SVF+AFT cases compared to AFT, in patients undergoing Nipple Sparing Mastectomy (NSM). PATIENTS AND METHODS: A prospective study was designed to compare three groups of patients undergoing NSM followed by SVF+AFT, AFT or none (control group), after a two-stage breast reconstruction. Patients were strictly followed-up for at least 5-years from the second stage reconstructive procedure. Loco-regional and systemic recurrence rate were evaluated over time as the primary outcome. Logistic regression was used to investigate which factors were associated with recurrence events and independent variables of interest were: surgical technique, age above 50 years old, lympho-vascular invasion, oncological stage, adjuvant or neoadjuvant chemotherapy, adjuvant radiotherapy and adjuvant hormone therapy. RESULTS: 41 women were included in G1 (SVF+AFT), 64 in G2 (AFT), and 64 in G3 (control group). Loco-regional recurrence rate was 2.4% for G1, 4.7% for G2, and 1.6% for G3. Systemic recurrence was 7.3%, 3.1%, and 3.1%, respectively. Among the variables included, there were no significant risk factors influencing a recurrence event, either loco-regional or systemic. In particular, SVF+AFT (G1) did not increase the oncological recurrence. CONCLUSIONS: Our data suggest that both centrifuged and SVF-enhanced fat transfer have a similar safety level in comparison to patients who did not undergo fat grafting in breast reconstruction after NSM

On the ordeal of quinolone preparation via cyclisation of aryl-enamines; synthesis and structure of ethyl 6-methyl-7-iodo-4-(3-iodo-4-methylphenoxy)-quinoline-3-carboxylate

Recent studies directed to the design of compounds targeting the bc(1) protein complex of Plasmodium falciparum, the parasite responsible for most lethal cases of malaria, identified quinolones (4-oxo-quinolines) with low nanomolar inhibitory activity against both the enzyme and infected erythrocytes. The 4-oxo-quinoline 3-ester chemotype emerged as a possible source of potent bc(1) inhibitors, prompting us to expand the library of available analogs for SAR studies and subsequent lead optimization. We now report the synthesis and structural characterization of unexpected ethyl 6-methyl-7-iodo-4-(3-iodo-4-methylphenoxy)quinoline-3-carboxylate, a 4-aryloxy-quinoline 3-ester formed during attempted preparation of 6-methyl-7-iodo-4-oxo-quinoline-3-carboxylate (4-oxo-quinoline 3-ester). We propose that the 4-aryloxy-quinoline 3-ester derives from 6-methyl-7-iodo-4-hydroxy-quinoline-3-carboxylate (4-hydroxy-quinoline 3-ester), the enol form of 6-methyl-7-iodo-4-oxo-quinoline-3-carboxylate. Formation of the 4-aryloxy-quinoline 3-ester confirms the impact of quinolone/hydroxyquinoline tautomerism, both on the efficiency of synthetic routes to quinolones and on pharmacologic profiles. Tautomers exhibit different cLogP values and interact differently with the enzyme active site. A structural investigation of 6-methyl-7-iodo-4-oxo-quinoline-3-carboxylate and 6-methyl-7-iodo-4-hydroxy-quinoline-3-carboxylate, using matrix isolation coupled to FTIR spectroscopy and theoretical calculations, revealed that the lowest energy conformers of 6-methyl-7-iodo-4-hydroxy-quinoline-3-carboxylate, lower in energy than their most stable 4-oxo-quinoline tautomer by about 27 kJ mol(-1), are solely present in the matrix, while the most stable 4-oxo-quinoline tautomer is solely present in the crystalline phase.Fundacao para a Ciencia e Tecnologia (FCT - Portugal) [UID/Multi/04326/2013]; QREN-COMPETE-UE; CCMAR; FCT [SFRH/BD/81821/2011, RECI/BBB-BQB/0230/2012, UI0313/QUI/2013, UID/FIS/04564/2016]; FEDER/COMPETE-UE; [PTDC/QEQ-QFI/3284/2014 - POCI-01-0145-FEDER-016617]info:eu-repo/semantics/publishedVersio