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Background Sodium-glucose Cotransporter 2 inhibitors (SGLT2-i) have shown improved cardiovascular outcomes in type 2 diabetes mellitus (T2DM) that surpass their hypoglycaemic power. However, the inclusion criteria in the pivotal studies were broad in terms of cardiovascular disease, and there are no specific studies on patients with coronary artery disease (CAD). Purpose To compare, in patients with T2DM and extensive CAD, the hazard ratio (HR) of all-cause death in patients treated with or without SLGT2-I, adjusted by IPTW and treatment (revascularization) strategy. Secondary: To compare the adjusted HR of cardiovascular (CV) death, myocardial infarction (MI), stroke, or heart failure admission (HF) in patients treated with or without SLGT-I. Methods A single-centre retrospective observational study in patients with T2DM, with the first diagnosis of extensive CAD defined by >50% stenosis in LM or 3-vessels, and alive at discharge. The study was approved by the research ethics committee and recruited consecutive patients from 2015 (year of first SLGT2-I approval) to 2020. Patients with prior revascularization, severe renal failure (filtration rate Results We recruited 420 patients with a mean age of 71.2±11.1 years; 78.6% were male, 82.6% had hypertension, 72% hyperlipemia, 50.2% were smokers or former smokers, 52.9% had a history of previous myocardial infarction and 10.7% of stroke. Mean LVEF (%) was 51.5±1.5, creatinine clearance 73.94±22 ml/min and glycated haemoglobin (%) 7.3±1.2. The presentation was acute coronary syndrome in 44.3% (27% ST elevation/73% non-ST elevation). LM was affected in 29%; 3-vessel CAD was found in 86.7%; 2-vessel in 8.3%; 1-vessel in 3.8%, and 1.2% exclusively in the LM. Treatment strategy was PCI + OMT in 48.3%, CABG + OMT 39.8% and OMT only in 21.9%. T2DM treatment, secondary prevention treatment and metabolic control at follow up are presented in Table 1. A total of 104 patients (24.8%) started treatment with SGLT2-I during a mean of 1.6±1 years. At a mean follow-up of 3±1.6 years, mortality was 16.4%, CV mortality was 9.5%, 6.9% had a MI,3.3% had a stroke, and 11.4% had HF admission. Patients treated with SLGT2-I had a lower risk of all-cause death, cardiovascular death and the composite of CV death or HF (Table 2). After IPTW, the risk of all-cause death was persistently lower in the SLGT-I group Conclusion This real-life study found that in T2DM patients with LM or MVD only 1 out of 4 patients was treated with SGLT2-I as a part of their secondary prevention treatment. Those with SGLT2-I had a reduced risk of all-cause death (HR 0.34 [0.12–0.91], p=0,033) after IPTW and treatment (revascularization) strategy adjustment. Funding Acknowledgement Type of funding sources: None.

Background New-onset chest pain occurs in around 20% of patients with long COVID syndrome (LCS). Being the vascular endothelium one of the targets of the SARS-CoV-2 virus, we hypothesized that new onset anginal symptoms in LCS could be due to endothelium dysfunction and other non-obstructive causes of myocardial ischaemia. Methods We investigated 11 consecutive patients who developed new onset anginal chest pain, suggestive of myocardial ischaemia, after documented SARS-CoV-2 infection. Intracoronary assessment included endothelium-dependent evaluation with acetylcholine testing (Ach), and endothelium-independent assessment with coronary flow reserve (CFR) and microcirculatory resistance (MR). Criteria for positiveness of these tests and medical treatment recommendation were obtained from 2019 ESC guidelines and 2020 EAPCI consensus document on ischaemia with non-obstructive coronary arteries (INOCA). Results Mean patient age was 56 years (SD ± 15); 10 (91%) were female. In the acute COVID-19 phase, 4 patients (36%) had had pulmonary infiltrates and 2 (18%) required hospitalization. Conclusive non-invasive tests were obtained in 7 (64%), showing exercise-related myocardial ischaemia in 6 (86%). Coronary angiography ruled out obstructive epicardial stenoses in all the patients. Ach testing revealed abnormal endothelium-dependent responses in 9 (82%) patients: 5 (56%) had epicardial vessel and 4 (44%) microvascular spasm. Endothelium-independent assessment was abnormal in 6 (54%) cases, with abnormal CFR in 2 (33%), abnormal MR in 2 (33) and both abnormal CFR and MR in 2 (33%) patients. The most frequent endotype was combined endothelium dependent- and independent abnormalities (6/9, 67%). Stratified medical treatment according to endotype led to significant improvement in Seattle Angina Scores for angina frequency (+22 points, p=0.013) and a notable trend towards angina stability (+25 points, p=0.093) at a mean follow-up time of 222 days. Conclusions Myocardial ischaemia of non-obstructive origin is common in patients with chest pain and LCS. Vasomotor abnormalities related to endothelial dysfunction occurred in 82% of patients, frequently associated to impaired microvascular vasodilation or high microvascular resistance. Stratified medical treatment led to significant improvement in angina stability and frequency. Funding Acknowledgement Type of funding sources: None.

The purpose of this mixed method research using concurrent nested (embedded) design was to investigate the relationship between the extent of practice of management functions and the extent of practice of management skills of school administrators. The management functions were very good which was obtained from the planning, organizing, leading, and controlling. The management skill was very good which was obtained from conceptual and design, interpersonal or human and technical. The capabilities on organizing and controlling need maintenance or even enhancement while the constraints on planning and leading need to be addressed by the administrators in their practice of millennial management functions. The only capability on skills is on the human relations/interpersonal skills need maintenance or enhancement while the constraints on conceptual and technical skills need improvements. The validated output is humbly recommended for use by the school administrators to enhance the practice of management functions and management skills. The result of this study is further recommended as basis of future researchers in assessing the performance of school administrators of other countries.

First-principles calculations have been carried out to investigate the stability, structural and electronic properties of two-dimensional (2D) hydrogenated GaAs with three possible geometries: chair, zigzag-line and boat configurations. The effect of van der Waals interactions on 2D H-GaAs systems has also been studied. These configurations were found to be energetic and dynamic stable, as well as having a semiconducting character. Although 2D GaAs adsorbed with H tends to form a zigzag-line configuration, the energy differences between chair, zigzag-line and boat are very small which implies the metastability of the system. Chair and boat configurations display a [Formula: see text]-[Formula: see text] direct bandgap nature, while pristine 2D-GaAs and zigzag-line are indirect semiconductors. The bandgap sizes of all configurations are also hydrogen dependent, and wider than that of pristine 2D-GaAs with both PBE and HSE functionals. Even though DFT-vdW interactions increase the adsorption energies and reduce the equilibrium distances of H-GaAs systems, it presents, qualitatively, the same physical results on the stability and electronic properties of our studied systems with PBE functional. According to our results, 2D buckled gallium arsenide is a good candidate to be synthesized by hydrogen surface passivation as its group III-V partners 2D buckled gallium nitride and boron nitride. The hydrogenation of 2D-GaAs tunes the bandgap of pristine 2D-GaAs, which makes it a potential candidate for optoelectronic applications in the blue and violet ranges of the visible electromagnetic spectrum.

Graphene/MoS$_2$ van der Waals (vdW) heterostructures have promising technological applications due to their unique properties and functionalities. Many experimental and theoretical research groups across the globe have made outstanding contributions to benchmark the properties of graphene/MoS$_2$ heterostructures. Even though some research groups have already made an attempt to model the graphene/MoS$_2$ heterostructures using {\it first-principles} calculations, there exists several discrepancies in the results from different theoretical research groups and the experimental findings. In the present work, we revisit this problem by first principles approach and address the existing discrepancies about the interlayer spacing between graphene and MoS$_2$ monolayers in graphene/MoS$_2$ heterostructures, and the location of Dirac points near Fermi-level. We find that the Tkatchenko--Scheffler method efficiently evaluates the long-range vdW interactions and accurately predicts interlayer spacing between graphene and MoS$_2$ sheets. We further investigate the electronic, mechanical and vibrational properties of the optimized graphene/MoS$_2$ heterostructures created using 5$\times$5/4$\times$4 and 4$\times$4/3$\times$3 supercell geometries having different magnitudes of lattice mismatch. The effect of the varying interlayer spacing on the electronic properties of heterostructures is discussed. Our phonon calculations reveal that the interlayer shear and breathing phonon modes, which are very sensitive to the weak vdW interactions, play vital role in describing the thermal properties of the studied systems. The thermodynamic and elastic properties of heterostructures are further discussed. A comparison between our results and the results reported from other research groups is presented.

The purpose of this study is to study the model of international trade cooperation between Thailand, Laos, and Myanmar, to develop the well-being of the people along the northern border of Thailand, in order to reduce poverty of the people living in the area of the 3 countries. The study is done from documents, in-depth interviews with 50 Thai, Laos and Myanmar business people in the trading field, those involved in supporting the trading, local people in the area, and 25 main informants. From the study it is found that: 1) The model of creating the link of international trading between the countries and the sustainable development of well-being for the people in the area, is the expansion of economic growth, leading to employment, earning income, reducing the poverty, having no impact on society and the environment, 2) The model of international trading cooperation between the countries to develop the well-being of the people, through 3 channels of driving forces: Price Channel, Enterprise Channel and Government Channel. Driving in 3 dimensions: Economic Dimension, Environmental Dimension and Social Dimension.

In my experience as a foreign teacher for more than a decade in Thailand, I always reminded my students that education is a key to open up new door of opportunities locally and internationally. Everyone needs a key that is fulfilling, invigorating and self-sustaining. Opportunities rarely knock on us. The feeling of being left behind others in terms of skills and abilities in the academic performance is a big challenge to identify learning strategy to progress. The classroom environment is unhealthy if this happened and experienced by some slow learners. At present, students who are now considered millennial is said to be smart and brain based. The only thing teachers must know is how to support and develop their existing brilliance so that they can compete with national and global professions. Reading is one of the four significant language skills for academic success and professional development (Dorkchandra 2010). Reading is one of the most salient education tools because it is our convenient means to access into the rich repository of knowledge accumulated and preserved by mankind in printed matter. It is largely through reading that we require much of the information of concepts which to be remembered. Reading is considered as the most important subjects in the curriculum. The significance of reading as a school subject cannot refuse. Every student who fails to comprehend on what they are reading may unsubstantially provide answers on questions being asked upon them. Skill in reading is a fundamental factor, a must needs that enable help or inspire that child to succeed in school and later in his activities. Failure or incompetence in the other subjects in the curriculum maybe attributed to lack of interest, skill proficiency, weakness and comprehension in reading. If the child experience in reading were not positive his vocational adoption and efficiency would be severely affected. Findings and Discussions This chapter presents, analyzes and interprets the finding of the study. The table shows the data of the pretest and posttest. Table 1 show that the weighted averages mean of the posttest (18.18) was greater than the pretest (16.86). The averages mean of the pretest scores and posttest scores was 1.28 As a result, the comprehension level of the students when difficult words are unlocked prior to story reading has a higher mean (18.18) rather than the pretest (16.86). This means that it is really an effective strategy in teaching. This could help the students develop their critical thinking and to help them understand the story well. Moreover, it really arouses the interest of the learners to participate in the classroom discussion. Conclusion and Recommendation Based on the data gathered and tabulated, the researcher concluded that; 1. There is a difference between the pretest and posttest where the posttest scores are higher than the pretest scores. 2. Unlocking difficult words in reading stories is very effective in improving reading comprehension of students. Recommendations: Based on the following findings and conclusion of this study in improving performance in reading comprehension, the researcher recommends that; 1. The result of this study should inspire English teachers to unlocked difficult words after reading the short story in improving students’ performance. 2. Seminar-workshop must be conducted to equip teachers with the reading knowledge and skills needed in unlocking difficult words before reading them story. 3. Unlocking difficult words should be conducted for the students especially the slow learners. 4. Parents should be updated and informed of their children’s reading deficiencies so they can help them to overcome their difficulties on reading comprehension.

This research has the purpose of studying the correlation between the quality of airline services and the loyalty of the users of Thailand domestic airlines. The sample group consisted of users of domestic airline services, by stratified random sampling, using the airlines in stratification. 384 people in the sample group are from the Krejcie and Morgan chart. Tools used are questionnaires. Statistic are by means, pearson’s simple correlation moment product. From the study it is found that 1) The quality levels of Thailand domestic airline services are high 2) The levels of the loyalty of the users of domestic airline services are high and 3) The quality of airline services has an overall correlation with the loyalty of the users of airline services at a high level, with statistic significant at .01 and correlation coefficient at .720.

Dynamic mechanical analysis (DMA) measurements have been used for determining the viscoelastic behaviour of polystyrene (PS) nanocomposites containing a 1 wt.% of single- or multi-walled carbon nanotubes, both pristine (SWCNT and MWCNT) and modified by previous treatment with a room-temperature ionic liquid (SWCNTm and MWCNTm). Two sets of multiple frequency tests have been carried out. The Arrhenius relationship has been used to estimate the apparent activation energies for the glass transition. Master curves have been generated using the time–temperature superposition principle. The nanocomposites show an increase of the activation energy up to an 8% with respect to PS, in the order PS + MWCNT > PS + MWCNTm > PS + SWCNTm > PS + SWCNT > PS. The nanophases also induce a displacement of the onset of the storage modulus to longer times following the order PS + SWCNTm > PS + SWCNT > PS + MWCNT > PS + MWCNTm > PS, at 40 °C. At higher temperatures, the storage modulus onset is very similar for all materials. In the case of PS + SWCNTm, the period of time for the onset of the storage modulus is multiplied by a factor of 28 with respect to PS. The surface modification of the SWCNT by the ionic liquid could improve the interfacial compatibility. The results described here show that a very low proportion of carbon nanotubes can effectively improve the long-term stability of PS under service temperature conditions.

Multi-walled carbon nanotubes, both neat (MWCNT) and modified (MWCNTm) by the room-temperature ionic liquid (IL) 1-octyl-3-methylimidazolium tetrafluoroborate ([OMIM]BF4), were added in a 1 wt% to polystyrene (PS) to obtain the new nanocomposites (PS + MWCNT and PS + MWCNTm). Friction coefficients and abrasive wear from instantaneous penetration depth, residual depth and viscoelastic recovery were determined for compression-moulded materials as a function of applied normal load and of the number of successive scratches. The new nanocomposites improve the abrasion resistance of neat PS and of the analogous PS nanocomposites containing neat and IL-modified single-walled carbon nanotubes. The lowest friction coefficient and residual depth values, after 15 scratches, under the whole range of applied loads are obtained for PS + MWCNTm, with maximum reduction under the most severe conditions. The influence of sliding direction with respect to flow was studied for injection-moulded PS + MWCNTm under multiple scratching. The most severe surface damage is observed in the transverse direction to injection flow, while the lowest friction coefficient and the highest abrasion resistance and viscoelastic recovery values are obtained in the direction parallel to injection flow, due to the higher mobility of the polymer chains and the additives. Thermal analysis (DSC and TGA), Raman spectroscopy, transmission electron microscopy, X-ray diffraction and XPS surface analysis have been used as characterization techniques. XPS shows that the IL molecules are present on the nanotube surface. According to TGA, the IL content in MWCNTm can be estimated to be of a 12 wt%. Mechanisms of surface damage are discussed upon scanning electron microscopy, 3-D surface topography, surface roughness and profilometry observations.

FRIDA will be a near infrared imager and integral field spectrograph covering the wavelength range from 0.9 to 2.5 microns. FRIDA will work in two observing modes: direct imaging and integral field spectroscopy. This paper presents the main structure of the FRIDA mechanisms control system. In order to comply with a high level of re-configurability FRIDA will comprise eight cryogenic mechanisms and one room temperature mechanism. Most of these mechanisms require high positioning repeatability to ensure FRIDA fulfills with high astronomical specifications. In order to set up the mechanisms positioning control parameters a set of programs have been developed to perform several tests of mechanisms in both room and cryogenic environments. The embedded control software for most of the FRIDA mechanisms has been developed. A description of some mechanisms tests and the software used for this purpose are presented.

Pristine single-walled carbon nanotubes (CNTs) were dispersed in the room-temperature ionic liquid (IL) 1-octyl, 3-methylimidazolium tetrafluoroborate ([OMIM]BF4) by grinding and ultrasounds. Excess IL was removed to obtain single-walled carbon nanotubes modified by [OMIM]BF4 (mCNTs). mCNTs were added in a 1 wt.% to polystyrene (PS), polymethylmethacrylate (PMMA) and polycarbonate (PC) to obtain PS + mCNT, PMMA + mCNT and PC + mCNT. The dry tribological performance of the new nanocomposites was studied against AISI 316L stainless steel pins and compared with that of the neat polymers and with the nanocomposites containing pristine carbon nanotubes without IL (PS + CNT; PMMA + CNT and PC + CNT). The maximum wear rate and friction coefficient reduction is obtained for PS + mCNT. Results are discussed upon the basis of optical, SEM and TEM microscopy, thermogravimetric analysis (TGA), Raman spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS).

ABINIT is a package whose main program allows one to find the total energy, charge density, electronic structure and many other properties of systems made of electrons and nuclei, (molecules and periodic solids) within Density Functional Theory (DFT), Many-Body Perturbation Theory (GW approximation and Bethe-Salpeter equation) and Dynamical Mean Field Theory (DMFT). ABINIT also allows to optimize the geometry according to the DFT forces and stresses, to perform molecular dynamics simulations using these forces, and to generate dynamical matrices, Born effective charges and dielectric tensors. The present paper aims to describe the new capabilities of ABINIT that have been developed since 2009. It covers both physical and technical developments inside the ABINIT code, as well as developments provided within the ABINIT package. The developments are described with relevant references, input variables, tests and tutorials. Program summary: . Program title: ABINIT. . Catalogue identifier: AEEU_v2_0. . Program summary URL: . http://cpc.cs.qub.ac.uk/summaries/AEEU_v2_0.html . . Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland. . Licensing provisions: GNU General Public License, version 3. . No. of lines in distributed program, including test data, etc.: 4845789. . No. of bytes in distributed program, including test data, etc.: 71340403. . Distribution format: tar.gz. . Programming language: Fortran2003, PERL scripts, Python scripts. . Classification: 7.3, 7.8. . External routines: (all optional) BigDFT [2], ETSF_IO [3], libxc [4], NetCDF [5], MPI [6], Wannier90 [7], FFTW [8]. . Catalogue identifier of previous version: AEEU_v1_0. . Journal reference of previous version: Comput. Phys. Comm. 180 (2009) 2582. . Does the new version supersede the previous version?: Yes. The abinit-7.10.5 version is now the up to date stable version of ABINIT. . Nature of problem: . This package has the purpose of computing accurately material and nanostructure properties: electronic structure, bond lengths, bond angles, primitive cell size, cohesive energy, dielectric properties, vibrational properties, elastic properties, optical properties, magnetic properties, non-linear couplings, electronic and vibrational life-times, and others. . Solution method: . Software application based on Density Functional Theory, Many-Body Perturbation Theory and Dynamical Mean Field Theory, pseudopotentials, with plane waves or wavelets as basis functions. . Reasons for new version: . Since 2009, the abinit-5.7.4 version of the code has considerably evolved and is not yet up to date. The abinit- 7.10.5 version contains new physical and technical features that allow electronic structure calculations impossible to carry out in the previous versions. . Summary of revisions: . •new physical features: quantum effects for the nuclei treated by the Path-integral Molecular Dynamics; finding transition states using image dynamics (NEB or string methods); two component DFT for electron-positron annihilation; linear response in a Projector Augmented-Wave approach -PAW-, electron-phonon interactions and temperature dependence of the gap; Bethe Salpeter Equation -BSE-; Dynamical Mean Field Theory (DMFT).•new technical features: development of a PAW approach for a wavelet basis; parallelisation of the code on more than 10,000 processors; new build system.•new features in the ABINIT package: tests; test farm; new tutorials; new pseudopotentials and PAW atomic data tables; GUI and postprocessing tools like the AbiPy and APPA libraries. . Running time: . It is difficult to answer to the question as the use of ABINIT is very large. On one hand, ABINIT can run on 10,000 processors for hours to perform quantum molecular dynamics on large systems. On the other hand, tutorials for students can be performed on a laptop within a few minutes. . References: . 1 http://www.gnu.org/copyleft/gpl.txt 2 http://bigdft.org 3 http://www.etsf.eu/fileformats 4 http://www.tddft.org/programs/octopus/wiki/index.php/Libxc 5 http://www.unidata.ucar.edu/software/netcdf 6 https://en.wikipedia.org/wiki/Message_Passing_Interface 7 http://www.wannier.org 8M. Frigo and S.G. Johnson, Proceedings of the IEEE, 93, 216-231 (2005). . . (Less)

FRIDA is a diffraction-limited imager and integral-field spectrometer that is being built for the adaptive-optics focus of the Gran Telescopio Canarias. In imaging mode FRIDA will provide scales of 0.010, 0.020 and 0.040 arcsec/pixel and in IFS mode spectral resolutions of 1500, 4000 and 30,000. FRIDA is starting systems integration and is scheduled to complete fully integrated system tests at the laboratory by the end of 2017 and to be delivered to GTC shortly thereafter. In this contribution we present a summary of its design, fabrication, current status and potential scientific applications., To appear in the proceedings of SPIE conference 9908 "Ground-based and Airborne Instrumentation for Astronomy VI". 8 pages

We present the design concept and validation of a cryogenic lens mount for a noncemented doublet for the near-infrared diffraction limited instrument FRIDA. The design uses an autocentering mount that maintains the relative alignment of the lenses, acting against any displacement that may be induced by external forces by automatically returning the lenses to their nominal positions. Autocentering techniques have been used for instruments at room temperature with relatively relaxed image quality requirements. We present in detail its application to a mount for a cryogenic instrument working at the diffraction limit. The design has been tested on the collimator of FRIDA, a noncemented doublet of CaF2 and S-FTM16. We describe the alignment requirements of the system, and we show the calculations that ensure that the lenses will suffer both appropriate stresses and temperature differences. We present the experimental validation of a prototype, demonstrating that the design delivers an excellent performance without inducing unnecessary stresses on the optical components, provided that the lenses are previously aligned with very high precision.

FRIDA (inFRared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias (GTC)) is designed as a diffraction limited instrument that will offer broad and narrow band imaging and integral field spectroscopy capabilities with low, intermediate and high (R ~ 30,000) spectral resolutions, to operate in the wavelength range 0.9 – 2.5 μm. The integral field unit is based on a monolithic image slicer and the imaging and IFS observing modes will use the same Teledyne 2Kx2K detector. FRIDA will be based on a Nasmyth B of GTC, behind the adaptive optics (AO) system. The key scientific objectives of the instrument include studies of solar system bodies, low mass objects, circumstellar outflow phenomena in advanced stages of stellar evolution, active galactic nuclei high redshift galaxies, including resolved stellar populations, semidetached binary systems, young stellar objects and star forming environments. FRIDA subsystems are presently being manufactured and tested. In this paper we present the challenges to perform the verification of some critical specifications of a cryogenic and diffraction limited NIR instrument as FRIDA. FRIDA is a collaborative project between the main GTC partners, namely, Spain, Mexico and Florida.

FRIDA will be a near infrared imager and integral field spectrograph covering the wavelength range from 0.9 to 2.5 microns. Primary observing modes are: direct imaging and integral field spectroscopy. This paper describes the main advances in the development of the electronics and control system for both the mechanisms and house-keeping of FRIDA. In order to perform several tests of mechanisms in both room and cryogenic environments, a set of programs had been developed. All variables of the vacuum control system were determined and the main control structure based on one Programmable Logic Controller (PLC) had been established. A key function of the FRIDA’s control system is keeping the integrity of cryostat during all processes, so we have designed a redundant heating control system which will be in charge of avoiding cryostat inner overheating. In addition, some improvements of cryogenic and room temperature cabling structure are described.

FRIDA is a diffraction limited imager and integral field spectrometer that is being built for the Gran Telescopio Canarias. FRIDA has been designed and is being built as a collaborative project between institutions from Mexico, Spain and the USA. In imaging mode FRIDA will provide scales of 0.010, 0.020 and 0.040 arcsec/pixel and in IFS mode spectral resolutions R ~ 1000, 4,500 and 30,000. FRIDA is starting systems integration and is scheduled to complete fully integrated system tests at the laboratory by the end of 2015 and be delivered to GTC shortly after. In this contribution we present a summary of its design, fabrication, current status and potential scientific applications.

The nulling coronagraph, first proposed by Roddier and Roddier, uses a small mask (less than half the size of the central Airy spot) that shifts the phase of the incoming light by 180° to strongly attenuate the Airy spot as well as the rings. We report on both theoretical and laboratory performance. In our laboratory experiment, we reduce the peak intensity of the Airy pattern by a factor of 16. We derive estimates of the performance of a nulling coronagraph used on a telescope equipped with an adaptive optics system, based upon the performance of the University of Hawaii Hokupa'a adaptive optics system. On a 3.6 m telescope at 1.65 μm, it is found that a tip/tilt amplitude lower than 20 mas is needed for such a coronagraph to yield an extinction better than 2 stellar mag.

FRIDA has been conceived as the first science instrument for the adaptive optics system of the Gran Telescopio Canarias (GTC). It is designed to be installed at the Nasmyth A platform, behind the GTC adaptive optics system. FRIDA will be a diffraction limited, near infrared imager and integral field spectrograph sensitive from 0.9 to 2.5 μm. It may also include provisions for future upgrades such as coronographic masks and long slits. FRIDA is a collaborative project between the Instituto de Astronomia, UNAM, Mexico, the Instituto de Astrofisica de Canarias, Spain, and the Astronomy Department of the University of Florida, USA.

The electronic band structures of MoS2 monolayer and 2H1 bulk polytype are studied within density-functional theory (DFT) and many-body perturbation theory (GW approximation). Interlayer van der Waals (vdW) interactions, responsible for bulk binding, are calculated with the postprocessing Wannier functions method. From both fat bands and Wannier functions analysis, it is shown that the transition from a direct band gap in the monolayer to an indirect band gap in bilayer or bulk systems is triggered by medium- to short-range electronic interactions between adjacent layers, which arise at the equilibrium interlayer distance determined by the balance between vdW attraction and exchange repulsion. The semiconductor-to-semimetal (S-SM) transition is found from both theoretical methods: around c=10.7 A and c=9.9 A for DFT and GW, respectively. A metallic transition is also observed for the interlayer distance c=9.7 A. Dirac conelike band structures and linear bands near Fermi level are found for shorter c lattice parameter values. The VdW correction to total energy was used to estimate the pressure at which S-SM transition takes place from a fitting to a model equation of state.

LIF is a pleiotropic cytokine that can act as an immunomodulatory factor in different biological processes, such as embryo implantation, organ transplantation tolerance and multiple sclerosis. Here, we have observed that in tumors expressing LIF, its blockade inhibits tumor growth, and that the anti-tumor effect of LIF neutralization is mediated by the polarization of tumor-associated myeloid cells (TAMCs). LIF sustains the expression of CCL22, MRC1 and CD163 in human healthy monocytes and in TAMCs from mouse syngeneic (non-small cell lung cancer, ovarian cancer and colorectal cancer) models, patient-derived xenograft models and organotypic cultures from glioblastoma. We show that LIF blockade down-regulates CCL22 secretion by TAMCs preventing regulatory T cell and inducing effector T and NK cell tumor infiltration, leading to an increase in tumor cell apoptosis and an anti-tumor response. A positive correlation between M2-like markers and LIF expression has been observed in glioblastoma patients, and high levels of these factors confer poor prognosis. Moreover, we have studied one of the multiple mechanisms through which LIF could modulate the inhibition of effector T and NK cells: the regulation of PD-1/PDL1 axis. We have seen that after anti-LIF treatment of tumor-bearing mice, the expression of PDL1 decreases in tumor cells and in TAMCs. Furthermore, a positive correlation between PDL1 and LIF expression has been observed in glioblastoma patients, and both proteins also correlate with CD44 expression, a marker for cancer-initiating cell (CIC) population. High levels of these three factors confer poor prognosis. Thus, we have found that LIF acts as an immune-suppressor in cancer recapitulating its normal function in other biological processes. LIF is a bridge between the innate and adaptive immune responses through the induction of CCL22 in TAMCs and subsequent regulation of regulatory and effector T and NK cells. Our results identify LIF as a promising immuno-oncology therapeutic target and establish the translational potential of anti-LIF agents.

FRIDA will be a common-user near infrared imager and integral field spectrograph covering the wavelength range from 0.9 to 2.5 microns. Primary observing modes driven the instrument design are two: direct imaging and integral field spectroscopy. FRIDA will be installed at the Nasmyth-B platform of the Gran Telescopio Canarias (GTC) behind the GTC Adaptive Optics (GTCAO) system. Instrument will use diffraction-limited optics to avoid degrading the high Strehl ratios derived by the GTCAO system in the near infrared. High-performance astronomical instruments with a high reconfiguration degree as FRIDA, not only depends on optical and mechanical efficient designs but also on the good quality of its electronics and control systems design. In fact, astronomical instruments operating performance on telescope greatly relies on electronics and control system. This paper describes the main design topics for the FRIDA electronics and mechanisms control system, pointing on the development that these areas have reached on the project status. FRIDA Critical Design Review (CDR) was held on September 2011.

OSIRIS (Optical System for Imaging and low Resolution Integrated Spectroscopy) was the optical Day One instrum ent for the 10.4m Spanish telescope GTC . It is installed at the Observatorio del Roque de Los Muchachos (La Palma, Spain). This instrument has been operational since March -2009 and covers from 360 to 1000 nm. OSIRIS observing modes include direct imaging w ith tunable and conventional filters, long slit and low resolution spectroscopy. OSIRIS wide field of view and high efficiency provide a powerful tool for the scientific exploitation of GTC. OSIRIS was developed by a Consortium formed by the Instituto de A strofisica de Canarias (IAC) and the Instituto de Astronomia de la Universidad Nacional Autonoma de Mexico (IA -UNAM). The latter was in charge of the optical design, the manufacture of the camera and collaboration in the assembly, integration and verificat ion process. The IAC was responsible for the remaining design of the instrument and it was the project leader. The present paper considers the development of the instrument from its design to its present situation in which is in use d by the scientific comm unity. Keywords: Tunable filter s, imaging, spectroscopy, fast spectrophotometry, GTC , camera, optical instruments

FRIDA (inFRared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias) has been designed as a cryogenic and diffraction limited instrument that will offer broad and narrow band imaging and integral field spectroscopy (IFS). Both, the imaging mode and IFS observing modes will use the same Teledyne 2Kx2K detector. This instrument will be installed at Nasmyth B station, behind the GTC Adaptive Optics system. FRIDA will provide the IFS mode using a 30 slices Integral Field Unit (IFU). This IFU design is based on University of Florida FISICA where the mirror block arrays are diamond turned on monolithic metal blocks. FRIDA IFU is conformed mainly by 3 mirror blocks with 30 spherical mirrors each. It also has a Schwarzschild relay based on two off axis spherical mirrors and an afocal system of two parabolic off axis mirrors. Including two insertion mirrors the IFU holds 96 metal mirrors. Each block or individual mirror is attached on its own mechanical mounting. In order to study beam interferences with mechanical parts, ghosts and scattered light, an iterative optical-mechanical modeling was developed. In this work this iterative modeling is described including pictures showing actual ray tracing on the opto-mechanical components.

FRIDA (inFRared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias) is designed as a diffraction limited instrument that will offer broad and narrow band imaging and integral field spectroscopy capabilities with low (R similar to 1,500), intermediate (R similar to 4,500) and high (R similar to 30,000) spectral resolutions to operate in the wavelength range 0.9 - 2.5 mu m. The integral field unit is based on a monolithic image slicer. The imaging and IFS observing modes will use the same Teledyne 2K x 2K detector. FRIDA will be based at the Nasmyth B platform of GTC, behind the AO system. The key scientific objectives of the instrument include studies of solar system bodies, low mass objects, circumstellar outflow phenomena in advanced stages of stellar evolution, active galactic nuclei, high redshift galaxies, resolved stellar populations, semi-detached binary systems, young stellar objects and star forming environments. FRIDA is a collaborative project between the main GTC partners, namely, Spain, Mexico and Florida. In this paper, we present the status of the instrument design as it is currently being prepared for its manufacture, after an intensive prototypes' phase and design optimization. The CDR was held in September 2011.

The method to calculate van der Waals interactions based on maximally localized Wannier functions (MLWFs), proposed by Silvestrelli [Phys. Rev. Lett. 100 (2008) 053002], has been implemented within the ab initio DFT program ABINIT. In addition to a brief review of the theoretical background behind this methodology, we present the details of the implementation, which will help users to assess van der Waals corrections in both molecular and periodic systems with a negligible additional computational cost. Some tests on argon dimer, argon FCC solid, benzene dimer and bilayer of graphene are presented. A discussion about the reliability of the method is also included., We acknowledge the support of CONACYT, Mexico, under program FNRS-CONACYT Binational collaboration. Y.P. acknowledges funding by the Spanish MEC (FIS2007-65702-C02-01), “Grupos Consolidados UPV/EHU del Gobierno Vasco” (IT-319-07), as well as a contract funded by MICINN (PTA2008-0982-I) and ETORTEK-inanoGUNE (2008–2010). X.G. and Y.P. acknowledge support from e-I3 ETSF project (Contract Number 211956). T.R. and X.G. acknowledge financial support from the Communauté française de Belgique through the NANHYMO project (ARC 07/12-003). X.G. acknowledges financial support from the FRS-FNRS Belgium (FRFC Grant numbers 2.4.589.09.F and 2.4645.08), the Walloon region Belgium (RW project number 816849, WALL-ETSF), the Interuniversity Attraction Poles Program (P6/42) – Belgian State – Belgian Science Policy. A.H.R. also acknowledges the support of Conacyt-Mexico under project 152153. C.E. acknowledges support from Universidad Jorge Tadeo Lozano, Colombia.

Polymer-matrix nanocomposites are increasingly been applied as structural materials in the aerospace, automotive and chemical industries, in a number of tribological applications including such components as bearings, gears, cams, seals, vacuum pumps and in biological or medical applications in prothesis and implants, particularly in areas where traditional fluid lubricants can not be used. The base polymers studied have now extended from the original high temperature polymers to a wide range of thermoplastics and thermosets. In the present review we will focus on recent developments on polymer nanocomposites tribology including nanoparticles, with an emphasis on polymer nanocomposites containing carbon nanotubes, which are experiencing a large expansion and, as the tribological performance is mainly a function of surface properties, we will consider not only bulk nanocomposites, but also the development of polymer matrix nanocomposite coatings, which present very promising applications in the reduction of friction and wear.

Single-walled carbon nanotubes (NT) and singlewalled carbon nanotubes modified (NTm) by the room-temperature ionic liquid 1-octyl, 3-methylimidazolium tetrafluoroborate ([OMIM]BF4), were added in a 1 wt.% to polymethylmethacrylate (PMMA) and processed by extrusion and injection moulding to obtain PMMA+NT and PMMA+NTm, respectively. Friction coefficients and abrasive wear of PMMA and PMMA nanocomposites from penetration depth, residual depth and viscoelastic recovery were determined under multiple scratching as a function of the number of passes of the indenter on the same groove. The effects of the moulding process, the additives and the sliding direction on the scratch resistance of PMMA were studied.

We describe diamond-turned material tests for the integral field unit (IFU) for the FRIDA instrument (inFRared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias). FRIDA is closely based on the design of the successful FISICA cryogenic infrared image slicing device, which used "monolithic" mirror arrays, diamond turned into single pieces of metal. FRIDA, however, will require better roughness characteristics than the 15nm RMS of FISICA to avoid light scatter in FRIDA's shorter wavelength limit (900nm). Al 6061 seems to be limited to this roughness level by its silicate inclusions so some new combination of materials that are compatible with FRIDA's Al 6061 structure must be found. To this end, we have tested six diamond-turned mirrors with different materials and different platings. We used the Zygo interferometer facility at IA-UNAM to do warm and cold profile measurements of the mirrors to investigate possible bimetallic deformation effects. We present a detailed comparison of the various performance characteristics of the test mirrors.

FRIDA (inFRared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias) has been designed as a diffraction limited instrument that will offer broad and narrow band imaging and integral field spectroscopy (IFS) capabilities with low, intermediate and high spectral resolutions to operate in the wavelength range 0.9 - 2.5 μm. The integral field unit is based on a monolithic image slicer based on the University of Florida FISICA. Both, the imaging mode and IFS observing modes will use the same Rockwell 2K×2K detector. FRIDA will be based at a Nasmyth focus of GTC, behind the GTCAO system. The FRIDA optical design, stray light analysis, tolerance analysis and manufacturing feasibility are described in this contribution.

OSIRIS is the optical Day 1 instrument for the 10.4 m GTC telescope. OSIRIS will cover the 365 to 1000 nm spectral range, featuring an 8.6×8.6 arcmin field of view, and capabilities for direct imaging, both long-slit and multiple object spectroscopy, and fast spectrophotometry. The combination of OSIRIS wide field, tunable filters plus charge shuffling array detectors, will constitute the most powerful instrument for studying faint emission-line sources at any redshift. The present contribution gives an overview of the instrument development, currently in its verification phase before commissioning on site. © 2007 Springer.

In March 2004, the Commissioning Instrument (CI) for the GTC was accepted in the site of The Gran Telescopio Canarias (GTC) located in La Palma Island, Spain. During the GTC integration phase, the CI will be a diagnostic tool for performance verification. The CI features four operation modes-imaging, pupil imaging, Curvature Wave-front sensing (WFS), and high resolution Shack-Hartmann WFS. The imaging mode permits to qualify the GTC image quality. The Pupil Mode permits estimate the GTC stray light. The segments figure, alignment and cophasing verifications are made with both WFS modes. In this work we describe the Commissioning Instrument and show some tests results obtained during the site acceptance process at the GTC site.

FRIDA (inFRared Imager and Dissector for the Adaptive optics system of the Gran Telescopio Canarias) has been designed as a diffraction limited instrument that will offer broad and narrow band imaging and integral field spectroscopy (IFS) capabilities with low, intermediate and high spectral resolutions to operate in the wavelength range 0.9 - 2.5 μm. The integral field unit is based on a monolithic image slicer and the imaging and IFS observing modes will use the same Rockwell 2Kx2K detector. FRIDA will be based at a Nasmyth focus of GTC, behind the AO system. The main design characteristics of FRIDA are described in this contribution. FRIDA is a collaborative project between the main GTC partners, namely, Spain, Mexico and Florida, lead by UNAM.

In March 2004 was accepted in the site of Gran Telescopio Canarias (GTC) in La Palma Island, Spain, the Commissioning Instrument (CI) for the GTC. During the GTC integration phase, the CI will be a diagnostic tool for performance verification. The CI features four operation modes-imaging, pupil imaging, Curvature Wave-front sensing (WFS), and high resolution Shack-Hartmann WFS. This instrument was built by the Instituto de Astronomia UNAM in Mexico City and the Centro de Ingenieria y Desarrollo Industrial (CIDESI) in Queretaro, Qro under a GRANTECAN contract after an international public bid. Some optical components were built by Centro de Investigaciones en Optica (CIO) in Leon Gto and the biggest mechanical parts were manufactured by Vatech in Morelia Mich. In this paper we made a general description of the CI and we relate how this instrument, build under international standards, was entirely made in Mexico.

"OSIRIS (Optical System for Imaging and low Resolution Integrated Spectroscopy) is the optical Day one instrument for the GTC and the only Spanish Day One instrument. With both instrument and telescope schedules matched, OSIRIS will be available as soon as the GTC is scientifically operational. In this contribution an overview of the instrument at the middle of 2004 is given."

OSIRIS (Optical System for Imaging and low Resolution Integrated Spectroscopy) is the optical Day One instrument for the 10.4m Spanish telescope GTC to be installed in the Observatorio del Roque de Los Muchachos (La Palma, Spain). This instrument, operational in mid-2004, covers from 360 up to 1000 nm. OSIRIS observing modes include direct imaging with tunable and conventional filters, long slit and multiple object spectroscopy and fast spectrophotometry. The OSIRIS wide field of view, high efficiency and the new observing modes (tunable imaging and fast spectrophotometry) for 8-10m class telescopes will provide GTC with a powerful tool for their scientific exploitation. The present paper provides an updated overview of the instrument development, of some of the scientific projects that will be tackled with OSIRIS and of the general requirements driving the optical and mechanical design.

Under a contract with the GRANTECAN, the Commissioning Instrument (CI) is a project developed by a team of Mexican scientists and engineers from the Instrumentation Department of the Astronomy Institute at the UNAM and the CIDESI Engineering Center. The CI will verify the Gran Telescopio Canarias (GTC) performance during the commissioning phase between First Light and Day One. The design phase is now completed and the project is currently in the manufacturing phase. The CI main goal is to measure the telescope image quality. To obtain a stable high resolution image, the mechanical structures should be as rigid as possible. This paper describes the several steps of the conceptual design and the Finite Element Analysis (FEA) for the CI mechanical structures. A variety of models were proposed. The FEA was useful to evaluate the displacements, shape modes, weight, and thermal expansions of each model. A set of indicators were compared with decision matrixes. The best performance models were subjected to a re-optimization stage. By applying the same decision method, a CI Structure Model was proposed. The FEA results complied with all the instruments specifications. Displacements values and vibration frequencies are reported.

This paper describes both the electronics design (ED) and the acceptance control system (ACS) of the Commissioning Instrument (CI) for the Gran Telescopio Canarias (GTC). The CI mainly comprises ten mechanisms accurately positioned by control algorithms, which in turn are programmed according to the CI operation modes. The control system is based on a CANopen protocol and is completely compatible with the GTC control system. CANopen is a serial communication protocol based on CAN bus. The CANopen features allow for the control system high reliability. A Reliability, Availability, Maintainability, and Safety (RAMS) analysis was carried out to guarantee the CI opto-mechanics and electronics performance.