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Ultrafast laser science witnesses a transformative change due to the introduction of robust, high repetition rate Yb based solid state lasers. We prove the ability of hollow-core fiber (HCF) post compression to keep pace with the constantly raising average powers and pulse energies provided by state-of-the-art lasers. Over a wide range of input parameters, HCFs can provide high transmissions in the 80%–90% range with greater than 10-fold compression. First, we describe a double stage HCF setup that compresses 80 W, 2 mJ, 338 fs pulses centered at 1030 nm down to sub-two optical cycles (6 fs FWHM) with 56 W output power. This 56-fold pulse compression is paired with an overall throughput of 70% and very good long term stability (1.5% StDev over 8 hours). Next, power scaling to 300 W with variable pulse energy and repetition rate (from 100 kHz, 3 mJ to 25 kHz, 12 mJ) is presented. We compressed 1.3 ps pulses of down to 100 fs in a single HCF at 300 W level. Finally, we reveal the potential of utilizing the ultrabroadband HCF output as a spectroscopy platform that can provide various, simultaneous outputs covering a wavelength range from 430 nm up to 12 $\mu$m.

The parallel 29Si magic angle spinning nuclear magnetic resonance (MAS NMR) and Fourier-transform infrared study of synthetic micas made it possible to compare structural features of the tetrasilicic magnesium mica K(Mg2.5□0.5) Si4O10(OH)2(TMM) and their K(Mg3)(Si3.5Mg0.5)O10(OH)2(TMMA) and K(Mg3)(Si3.5Be0.5)O10(OH)2(TMMB) derivatives. In the TMM mica, SiO4tetrahedra are elongated in the plane aband shortened along the c* direction with respect to those of the phlogopite (Phl) K(Mg3)(Si3Al)O10(OH)2. The substitution of Si4+by R2+(Mg2+or Be2+) produces, besides the 29Si MAS NMR signal of Si (3Si) at −91.2 ppm, new components at −84.4 or −87.5 ppm that correspond to Si (2Si1Mg) or Si(2Si1Be) environments. Tetrahedral cation distributions in TMM/TMMA, TMM/TMMB solid solutions are investigated with respect to the TMM/Phl series by means of NMR and Monte Carlo simulations, concluding that divalent Mg2+and Be2+are further dispersed than trivalent Al3+cations in tetrahedral sheets of micas. In three analyzed series, cation distributions display features between those of the homogeneous dispersion of charges of phlogopites and the maximum dispersion of charges of TMM derivatives. In three series, the location of charge deficits that compensate K+cations changes from octahedral in TMM to tetrahedral sheets in phlogopite and TMMA and TMMB derivatives.

Study Design Cross-sectional observational study in a prospective cohort.Objective To analyze the cervical alignment characteristics and their chain of correlation in a sample of asymptomatic individuals.Methods Asymptomatic adults who had full spinal radiographs performed. Cervical radiographic parameters were measured, including upper cervical curvature (McGregor line-C2), lower cervical curvature (C2-C7), McGregor slope, and sagittal vertical axis from C2-C7 (CSVA) and T1-slope (T1S). Subjects were stratified by age into 3 groups (18-39 years, 40-59 years, and >60 years), and radiographic parameters were compared across age groups and based on sex.Results 102 asymptomatic subjects (mean age, 50 years) were included. The T1S significantly increased with age, accompanied by an increase in C2-C7 lordosis. The cervical sagittal alignment, represented by CSVA, did not significantly differ based on age. There was a close correlation among the cervical sagittal parameters, such that the CSVA may be predicted based on the T1S and C2-C7 lordosis. Comparisons of the normative values identified in the present study with those reported in previous studies demonstrate variability in what constitutes normal in different populations.Conclusion This analysis of cervical alignment in a sample of asymptomatic volunteers revealed that with increasing age there is an observed increase in the sagittal inclination of the base of the cervical spine (T1S) that is accompanied by an increase in cervical lordosis as a means of maintaining cervical sagittal alignment (CSVA). The variability in what constitutes normal values for cervical parameters suggests that further study is warranted using standardized methodologies across diverse populations.

The efficient generation, accurate detection, and detailed physical tracking of energetic electrons are of applied interest for high harmonics generation, electron-impact spectroscopy, and femtosecond time-resolved scanning tunneling microscopy. We here investigate the generation of photoelectrons (PEs) by exposing plasmonic nanostructures to intense laser pulses in the infrared (IR) spectral regime and analyze the sensitivity of PE spectra to competing elementary interactions for direct and rescattered photoemission pathways. Specifically, we measured and numerically simulated emitted PE momentum distributions from prototypical spherical gold nanoparticles (NPs) with diameters between 5 and 70 nm generated by short laser pulses with peak intensities of 8.0 × 1012and 1.2 × 1013W/cm2, demonstrating the shaping of PE spectra by the Coulomb repulsion between PEs, accumulating residual charges on the NP, and induced plasmonic electric fields. Compared to well-understood rescattering PE cutoff energies for strong-field photoemission from gaseous atomic targets (10× the ponderomotive energy), our measured and simulated PE spectra reveal a dramatic cutoff-energy increase of two orders of magnitude with a significantly higher contribution from direct photoemission. Our findings indicate that direct PEs reach up to 93 % of the rescattered electron cutoff energy, in contrast to 20 % for gaseous atoms, suggesting a novel scheme for the development of compact tunable tabletop electron sources.

Study Design: Cross-sectional study.Objectives: Thus, this study aimed to assess the epidemiological profile of a patient sample that underwent spinal surgery regarding their nutritional and vitamin D status.Methods: Serum albumin and vitamin D (25-hydroxyvitamin D) levels were measured in patients with different spinal surgical approaches and various pathologies at a single institution. 112 patients were retrospectively identified for inclusion and stratified by age into 4 age groups and by pathology. The nutritional status of the patients was classified in vitamin D inadequacy (< 30ng/mL), vitamin D deficiency (<20ng/mL), and hypoalbuminemia (<3.5g/dL). Data was analyzed comparing vitamin D, and albumin means considering gender, age group, and pathologies.Results: Twenty-eight (25.2%) patients had hypoalbuminemia. There was no difference between gender (p = 0.988); there was a significant decrease in albumin concentration increasing the age (p < 0.001). The prevalence of hypoalbuminemia was significantly higher in patients with trauma, tumor and infection than in those patients with degenerative and deformity diseases (p = 0.003). The prevalence of vitamin D inadequacy was 33.7%, and that of deficiency was 62.2%, while severe deficiency (< 10 ng/mL) in 16.3%. The vitamin D concentration was significantly different among the pathologies (P = 0.047), the lower concentration occurring in patients with tumor.Conclusion: Older patients, as well as patients with tumor and infectious pathologies, seem to have a higher prevalence of hypoalbuminemia, inferring malnutrition. There was a low epidemic level of vitamin D concentration, almost all patients presenting some degree of hypovitaminosis D, independent of age, gender and nutritional status.

A promising alternative to Gaussian beams for use in strong field science is Bessel–Gauss (BG or Bessel-like) laser beams, as they are easily produced with readily available optics and provide more flexibility of the spot size and working distances. Here we use BG beams produced with a lens-axicon optical system for higher-order harmonic generation (HHG) in a thin gas jet. The finite size of the interaction region allows for scans of the HHG yield along the propagation axis. Further, by measuring the ionization yield in unison with the extreme ultraviolet (XUV), we are able to distinguish regions of maximum ionization from regions of optimum XUV generation. This distinction is of great importance for BG fields, as the generation of BG beams with axicons often leads to oscillations of the on-axis intensity, which can be exploited for extended phase-matching conditions. We observed such oscillations in the ionization and XUV flux along the propagation axis for the first time. As is the case for Gaussian modes, the harmonic yield is not maximum at the point of highest ionization. Finally, despite Bessel beams having a hole in the center in the far field, the XUV beam is well collimated, making BG modes a great alternative when spatial filtering of the fundamental is desired.

We present, to the best of our knowledge, a novel method for the generation of multiple Bessel-like (Bessel–Gauss) beams with tilted wavefronts whose optical phases can be controlled independently. In the far field multiple field-free regions develop that are persistent to interference effects and the optical phase. The extent of these field-free regions can be controlled through the tilt angle of the wavefront with a theoretical maximum resolution of 0.1 mrad. Experimentally we employ a spatial light modulator, a lens, and an axicon, each suitable for narrow-band (continuous-wave) and broadband operation. Because of the simplicity in the optical elements, the number of noninterfering Bessel-like beams can be scaled on demand for applications that require multiple sources for coherent imaging or multiple intense beams over a controllable region with the added benefit of a field-free region for detection. Here, for reasons of clarity, we characterized two beams.

Background: Despite the clinical importance, it has remained unclear which changes in the trunk muscle function parameters are more associated with the presence of vertebral fracture (VF). Aims: The aim of this study was to verify the association between the trunk muscle function performance and the presence of VF in older women with low bone mass. The secondary aim was to evaluate the correlation between trunk muscle function and both fall history and muscle mass. Methods: This cross-sectional study was composed by 94 women over 60 years within value of T-Score lumbar spine BMD  &lt;− 1.0 DP. Multidimensional evaluations were performed: appendicular skeletal muscle mass index (ASMI) was determined by the total body DEXA; the radiographic evaluations measured the degree of thoracic kyphosis and classification of VF. The trunk muscle function parameters, such as peak torque (PT), rate of torque development (RTD) and torque steadiness (TS) were evaluated by isokinetic dynamometer. The trunk muscle endurance was evaluated by the timed loaded standing test. The adjusted multivariate logistic regression model and multivariate linear regression were performed to verify the association between the variables studied. Results: The results showed that the trunk muscle function parameter with greater association with the presence of VF is TS extensors (OR = 1.70; p&lt; 0.001). The other two significant muscle parameters were: RTD30flexors (OR = 0.31; p= 0.033) and PT extensors (OR = 0.13; p= 0.009). No statistical association was found between the presence of VF and the ASMI and trunk muscle endurance. No correlation between trunk muscle function and fall history was observed. There was a weak correlation between ASMI and extensor PT (R2= 0.21; p= 0.027) and extensor RTD30(R2= 0.21; p= 0.026). Conclusions: This study demonstrated that deficit in trunk muscle function has shown a strong association with the presence of VF, highlighting issues heretofore unexplored regarding the association between VF with muscle power and motor control.

INTRODUCTION:

We generate few-cycle laser pulses from both the depleted pump and the signal of an optical parametric amplifier using self-phase modulation in a single hollow-core fiber. Despite the depleted pump’s poor spatial quality entering the fiber, it produces a field with less than 2.5 cycles. Moreover, we can simultaneously (same fiber) generate 4 cycle pulses from the signal. The coherent combination of both pulses allows for bandwidth spanning from 500 to 1500 nm. The geometry allows for minimal path differences of the two fields, paving a route for generating multi-octave, synthesized light transients centered in the near-infrared.

Denticulate ligaments (DLs) are pial extensions on each side of the spinal cord, comprising about 20 to 21 pairs of fibrous structures connecting the dura mater to the spinal cord. These ligaments are significant anatomical landmarks in the surgical approach to intradural structures. To our knowledge, there is no previous study on the detection of DLs using MRI.

Underfunding of the surgical treatment of complex spinal deformities has been an important reason for the steadily growing waiting lists in publicly funded healthcare systems. The aim of this study is to characterize the management of the treatment of spinal deformities in the public healthcare system.

Communicative methodology is the basis of the Learning Communities project. This is a school experience based on successful educational actions identified through research. Several pieces of evidence about the impact of this methodological approach will be presented within the framework of policy-making processes in educational issues on a national and international level. The dialogical process driven in the Basque Country of Spain among policy makers, teachers, families, and students will be described in the context of the Learning Communities project and how this process has changed the nature of educational policies. The effects of the use of communicative methodology in the project INCLUD-ED: Strategies for Inclusion and Social Cohesion in Europe from Education will also be explained. Both examples will demonstrate the link between dialogic policy and social transformation as well as the steps carried out in terms of educational policy.

To develop a version of the modified Japanese Orthopaedic Association (mJOA) scale that had been translated into Portuguese and cross-culturally adapted for the Brazilian population.

Solid‐phase microextraction (SPME) using a 100 μm poly(dimethylsiloxane) (PDMS) fiber, followed by gas chromatography (GC‐MS) determination, has been applied to the analysis of some monoterpenoids in honey. The extraction was performed by direct immersion of the fiber using a sampling period of 15 min with constant magnetic stirring (1100 rpm) and an extraction temperature of 20°C. A 7 mL sample volume of an aqueous solution of honey with 25% of NaCl was placed in 15 mL glass vial fitted with screw cap and PTFE/silicone septum. Desorption was performed directly in the gas chromatograph injector port during 5 min at 250°C using the splitless mode. The method is sensitive with detection limits between 11 and 25 μg L–1, precise with coefficients of variation in the range 1.28 and 3.71%, and linear over more than one order of magnitude. The related conditions were used for honey sample analyses with recoveries between 71.8 and 90.9%. SPME remains an attractive alternative technique due to its rapidity and because it is a solvent free extraction method.

Resumen: La Oncología Médica es una especialidad amplia en la que se integran numerosos aspectos de la medicina y requiere la interacción continua con el resto de especialidades. Los cuidados paliativos forman parte de ese abanico de materias que un oncólogo médico debe manejar. La paliación debe figurar como una actividad constante en todas las fases de la enfermedad; sin embargo, en los últimos años ha ido desapareciendo del ámbito oncológico y en muchas ocasiones se ha desarrollado y elaborado por médicos no oncólogos. En esto han influido numerosos factores socioeconómicos y políticos, la existencia de nuevos profesionales capacitados para desarrollar esta función y los propios oncólogos médicos. En el presente trabajo se revisa la situación actual de los cuidados paliativos y se propone un modelo de integración de niveles de actuación con el objetivo de dar una continuidad al tratamiento de los pacientes oncológicos desde el inicio del proceso hasta su finalización.

We studied the effects of the novel Na+/Ca2+exchange inhibitor KB‐R7943, 2‐[2‐[4‐(4‐nitrobenzyloxy)phenyl]ethyl]isothiourea methanesulphonate, on the native nicotinic receptors present at the bovine adrenal chromaffin cells, as well as on rat brain α3β4and α7nicotinic acetylcholine receptors (AChRs) expressed in Xenopusoocytes.As expected, KB‐R7943 blocked the Na+‐gradient dependent 45Ca2+uptake into chromaffin cells (IC50of 5.5 μM); but in addition, the compound also inhibited the 45Ca2+entry and the increase of cytosolic Ca2+concentration, [Ca2+]c, stimulated by 5 s pulses of ACh (IC50of 6.5 and 1.7 μM, respectively).In oocytes expressing α3β4and α7nicotinic AChRs, voltage‐clamped at −60 mV, inward currents elicited by 1 s pulses of 100 μMACh (IACh) were blocked by KB‐R7943 with an IC50of 0.4 μMand a Hill coefficient of 0.9.Blockade of α3β4currents by KB‐R7943 was noncompetitive; moreover, the blocker (0.3 μM) became more active as the ACh concentration increased (34 versus 66% blockade at 30 μMand 1 mMACh, respectively).Inhibition of α3β4currents by 0.3 μMKB‐R7943 was more pronounced at hyperpolarized potentials. If given within the ACh pulse (10 μM), the inhibition amounted to 33, 64 and 80% in oocytes voltage‐clamped at −40, −60 and −100 mV, respectively. The onset of blockade was faster and the recovery slower at −100 mV; the reverse was true at −40 mV.In conclusion, KB‐R7943 is a potent blocker of nicotinic AChRs; moreover, it displays many features of an open‐channel blocker at the rat brain α3β4AChR. These results should be considered when KB‐R7943 is to be used to study Ca2+homeostasis in cells expressing nicotinic AChRs and the Na+/Ca2+exchanger.

Objetivo: Aplicar la teoría del cambio al diseño y la evaluación de un programa para promover la actividad física en 11 zonas básicas de salud.

Rat α3β4or α7neuronal nicotinic acetylcholine receptors (AChRs) were expressed in Xenopus laevisoocytes, and the effects of various toxins and non‐toxin Ca2+channel blockers studied. Nicotinic AChR currents were elicited by 1 s pulses of dimethylphenylpiperazinium (DMPP, 100 μM) applied at regular intervals.The N/P/Q‐type Ca2+channel blocker ω‐conotoxin MVIIC inhibited α3β4currents with an IC50of 1.3 μM; the blockade was non‐competitive and reversible. The α7currents were unaffected.At 1 μM, ω‐conotoxin GVIA (N‐type Ca2+channel blocker) inhibited by 24 and 20% α3β4and α7currents, respectively. At 1 μM, ω‐agatoxin IVA (a P/Q‐type Ca2+channel blocker) did not affect α7currents and inhibited α3β4currents by only 15%.L‐type Ca2+channel blockers furnidipine, verapamil and, particularly, diltiazem exhibited a preferential blocking activity on α3β4nicotinic AChRs.The mechanism of α3β4currents blockade by ω‐conotoxins and diltiazem differed in the following aspects: (i) the onset and reversal of the blockade was faster for toxins; (ii) the blockade by the peptides was voltage‐dependent, while that exerted by diltiazem was not; (iii) diltiazem promoted the inactivation of the current while ω‐toxins did not.These data show that, at concentrations currently employed as Ca2+channel blockers, some of these compounds also inhibit certain subtypes of nicotinic AChR currents. Our data calls for caution when interpreting many of the results obtained in neurons and other cell types, where nicotinic receptor and Ca2+channels coexist.

In 39 red wines from Galicia (NW Spain), some trace elements were determined by atomic spectroscopy. Data were processed using multivariate chemometric techniques involving principal component analysis, discriminant analysis and K nearest neighbours to develop a typification for wine samples of Ribeira Sacra origin. The wines with Certified Brand of Origin (CBO) Ribeira Sacra can be differentiated from the wines of two other CBOs from Galicia: Ribeiro and Valdeorras. The latter CBOs make wines with the same grape variety; hence they are possible substitutes for falsification of Ribeira Sacra wines owing to their similar organoleptic properties. By means of multivariate techniques of data exploration, two main groups of samples (Ribeira Sacra and non-Ribeira Sacra wines) were observed. Exploratory analysis results were confirmed using supervised procedures of data classification. Using lithium and iron content as key features, a satisfactory classification was achieved. © 1999 Society of Chemical Industry

PF9404C is the S‐S diesteroisomer of a novel blocker of beta adrenergic receptors with vasodilatory properties. It causes a concentration‐dependent relaxation of rat aorta helical strips pre‐contracted with 10−6Mnoradrenaline (NA; IC5033 nM). It was equipotent to nitroglycerin (NTG; IC5049 nM), but much more potent than isosorbide dinitrate (ISD; IC5015,000 nM).Oxyhaemoglobin (10 μM) shifted to the right the concentration‐response curve for the relaxation induced by PF9404C (IC50530 nM) or NTG (IC5061 nM).Either methylene blue (MB) or ODQ (1 μMeach) largely prevented the vasorelaxing responses to increasing concentrations of PF9404C or NTG.In rat aorta smooth muscle cells, PF9404C increased the formation of cyclic GMP from 3 pmol mg−1protein in basal conditions, to 53 pmol mg−1protein in 10 μMPF9404C. Neither metoprolol nor carvedilol enhanced cyclic GMP.In the electrically driven guinea‐pig left atrium, PF9404C blocked the inotropic effects of isoprenaline in a concentration‐dependent manner. Its IC50(30 nM) was similar to that for S‐propranolol (22.4 nM) and lower than the IC50s for metoprolol (120 nM) and atenolol (192 nM). The beta‐adrenergic ligand (−)‐[3H]‐CGP12177 (0.2 nM) was displaced from its binding to rat brain membranes with Kiof 7 nM, 17 nM, 170 nMand 1.2 μMrespectively for PF9404C, S‐(−)propranolol, metoprolol, and atenolol.The data are consistent with the idea that the S‐S diesteroisomer PF9404C, is a potent vasorelaxing agent, as well as a blocker of cardiac beta adrenergic receptors. The mechanism of its vasorelaxing effects involves the slow generation of NO. This molecule can, therefore, exhibit antihypertensive and cardioprotective actions through a double mechanism, NO donation and beta blockade.

Soft cervical disc herniations can be treated by minimally invasive procedures with excellent results. Chemonucleolysis with chymopapain is one alternative to surgery that is shown to be innocuous within a strict technical framework. MR imaging allows an accurate diagnosis of the cause of cervical root compression, thus facilitating the choice of conventional surgery or minimally invasive procedures.

The atom distribution on several aluminosilicate frameworks has been analyzed by using a Monte Carlo method with a lattice gas model. The atom ordering is found to be dependent on the network topology, and, in particular, on the number n2of nextnearest tetrahedra in the network. For equal atomic fractions of Al and Si, increasing n2favors long-range order in the atom distribution.

Dexamethasone-based combinations have been the standard induction regimens in younger patients with multiple myeloma (MM) prior to stem cell transplantation. Bortezomib alone or in association with dexamethasone has shown significant activity in patients with both refractory/relapsed and newly diagnosed MM. We investigated the efficacy of bortezomib and dexamethasone administered on an alternating basis, the end-points of the study being response rate, kinetics of response, safety, stem cell mobilization and response postransplant. Patients with newly diagnosed MM under the age of 66 years and with adequate organ and function status were eligible. Patients were treated with bortezomib 1.3 mg/m2 on days 1, 4, 8 and 11 (cycles 1, 3, 5) and dexamethasone 40 mg p.o. on days 1–4, 9–12 and 17–20 (cycles 2, 4 and 6), followed by high dose-therapy intensification (HDT) with melphalan -200. Responses were evaluated by the EBMT criteria but a near-CR (n-CR) response category was included. Stem cell mobilization was performed after G-CSF priming. Between August, 2005 and March, 2006, 40 patients (18 M, 22F, median age 57 yrs) were enrolled. The M-protein type was IgG in 26 patients, IgA in 11 and light chain in 3. Six patients had extramedullary plasmacytomas. At the time of this analysis response data after the 6 cycles were available for 26 of the 40 patients. The overall response rate was 76% and the CR rate 15% (4 CR, 5 n-CR, 7 PR, 4 MR, 2 stable disease, 3 progressive disease, 1 non-evaluable because of treatment discontinuation due to toxicity after cycle 1). In patients who achieved at least PR the mean M-protein decrease was 84% (48% associated with bortezomib cycles and 36% with dexamethasone). Two responding patients showed disease progression immediately before HDT. In all thirteen patients mobilized to date stem cells could be adequately collected (median CD34+ cells: 4.85 x106/Kg; range 2–10.6) with only one apheresis. Toxicity was low and mainly consisted of grade 1 and 2 neutropenia, fever, GI symptoms, fatigue, peripheral neuropathy and thrombocytopenia. Ten (25%) patients developed mild peripheral neuropathy (grade 1=9 cases; grade 2=1 case) and 11 patients grade 1 thrombocytopenia. Grade 3 toxicity was only observed in 7 patients (neutropenia 6, skin/liver 1 case) and no patient developed grade 4 toxicity. Updated results on all patients along with cytogenetic data will be presented at the meeting. In conclusion, bortezomib alternating with dexamethasone is highly effective as up-front therapy in patients with MM, is associated with an extremely low toxicity and results in an excellent stem cell harvesting. The results of this trial support a short program of alternating bortezomib and dexamethasone as an effective and safe induction regimen for newly diagnosed younger myeloma patients.