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We present the accretion of magnetized supersonic winds onto a rotating black hole in three dimensions. We select representative spin-wind orientations in order to illustrate its effects on the evolution and morphology of the shock cone. The most important finding in the magnetized case, unlike the purely hydrodynamical scenario, is the formation of rarified spots where the magnetic field pressure dominates over the gas pressure. In these rarified spots we find the formation of eddies within the shock cone., Comment: 9 pages, 10 figures. Accepted for publication in MNRAS

Chemical protein synthesis (CPS) is a consolidated field founded on the high chemospecificity of amide-forming reactions, most notably the native chemical ligation (NCL), but also on new technologies such as the Ser/Thr ligation of C-terminal salicylaldehyde esters and the α-ketoacid-hydroxylamine (KAHA) condensation. NCL was conceptually devised for the ligation of peptides having a C-terminal thioester and an N-terminal cysteine. The synthesis of C-terminal peptide thioesters has attracted a lot of interest, resulting in the invention of a wide diversity of different methods for their preparation. The

In this research, changes in several characteristics of partially reduced titania were studied. The reduction process used made it possible to gradually observe changes in the material depending on the amount of reducing agent used. We used NaBH4 to impregnate commercial TiO2 with isopropyl alcohol. Impregnated TiO2 nanoparticles were dried and thermally treated in a nitrogen flow to obtain blue titania samples. Thorough spectroscopic characterization showed that oxygen atoms from hydroxyl groups, as well as from the surface, and the lattice of TiO2 was consumed. This caused changes in the surface and even in the bulk of TiO2 when the amount of reducing agent used was increased. Structural, optical, superficial, and textural characteristics were studied using XRD, Raman, DRS UV-Vis-NIR, Mid-DRIFT, XPS, and nitrogen adsorption/desorption isotherms. A photocatalytic test of the degradation of methylene blue dye was performed. Among different effects on the mentioned characteristics, we found evidence of changes in the surface properties of the blue titania samples and their probable effect on the photocatalytic properties. The reduction process implied a preponderant decrease in the surface hydrophilicity of the reduced samples, an effect shown for the first time in this type of material.

Let A ∈ C n × n and z 0 ∈ C be given, we compute the distance with respect to the spectral norm from A to the set of matrices that have z 0 as an eigenvalue of algebraic multiplicity at least 3 and geometric multiplicity at least 2, with an additional hypothesis on the maximum of a function. Furthermore, we determine a nearest matrix B to A in this set.

Multifunctional biocompatible materials have evoked considerable interest in the field of medical applications. Here we report the thermal decomposition preparation of homogeneous fluorescent-magnetic particles with a composite structure containing CoFe2O4 nanoparticles as nucleation seeds for fluorescent Gd2-xO3:Eux. The composite exhibited a wide range of fluorescence transitions in the whole visible spectrum, displaying 18 different emission peaks when excited at a 250 nm wavelength. Moreover, at low temperature the peaks of the composite were wider than the peaks of the fluorescent material, which may be attributed to a set of new energy levels due to a combination of Stark splitting with the magnetic field of CoFe2O4. Because this material is intended to be used for biomedical applications, the potential toxicity of the composite was tested using an invertebrate hemocyte cell model. The cells showed slight morphological and biochemical changes upon exposure to the composite; however, there was no increase in cell death at concentrations of up to 40 ppm. In addition, the material could be tracked by its fluorescence inside the cells, when excited at a more bio-friendly and less energetic wavelength of 405 nm. Furthermore, MRI showed T1 and T2 dual contrast with relaxivity values in the range of most reported materials.

Chemical protein synthesis (CPS) is a consolidated field founded on the high chemospecificity of amide-forming reactions, most notably the native chemical ligation (NCL), but also on new technologies such as the Ser/Thr ligation of C-terminal salicylaldehyde esters and the α-ketoacid-hydroxylamine (KAHA) condensation. NCL was conceptually devised for the ligation of peptides having a C-terminal thioester and an N-terminal cysteine. The synthesis of C-terminal peptide thioesters has attracted a lot of interest, resulting in the invention of a wide diversity of different methods for their preparation. The N-acylurea (Nbz) approach relies on the use of the 3,4-diaminobenzoic (Dbz-COOH) and the 3-amino-(4-methylamino)benzoic (MeDbz-COOH) acids; the latter disclosed to eliminate the formation of branching peptides. Dbz-COOH has been also used for the development of the benzotriazole (Bt)-mediated NCL, in which the peptide-Dbz-CONH2 precursor is oxidized to a highly acylating peptide-Bt-CONH2 species. Here, we have brought together the Nbz and Bt approaches in a versatile linker, the 1,2-diaminobenzene (Dbz). The Dbz combines the robustness of MeDbz-COOH and the flexibility of Dbz-COOH: it can be converted into the Nbz or Bt C-terminal peptides. Both are ligated in high yields, and the reaction intermediates can be conveniently characterized. Our results show that the Bt precursors have faster NCL kinetics that is reflected by a rapid transthioesterification (, This work has received funding from the grants RTI2018-096323-I00, PDI2021-128902OB-I00 (Spanish Ministerio de Ciencia e Innovación) and LCF/PR/HR20/52400006 (‘la Caixa’ Foundation). I. S.-C. thanks the AGAUR (Generalitat of Catalunya) for a predoctoral fellowship (2021 FI-B 00142), and P. K. thanks the Erasmus+ programme (European Commission) for a mobility fellowship. Rosaria Ragozzino (Erasmus+, University of Naples) is acknowledged for the preliminary electrophoretic experiments.

Regarding the pseudospectra of matrices it is easy to derive some conclusions from computer made graphics. However, those conclusions might be false without further analysis. Indeed, it happened when discussing the presence of a local maximum at the origin for the least singular value of the characteristic matrix of the n × n real Toeplitz matrix whose first row and first column are ( − 1 , − b , − b 2 , … , − b n − 1 ) and ( − 1 , 0 , 0 , … , 0 ) T , respectively, which was first taken into account by Demmel. In this paper, we determine the value of a local maximum for the last singular value of the characteristic matrix of such Toeplitz matrices in the cases n = 3 and n = 5 . We also specify the point where this local maximum is attained at.

In this work we report a series of Cu(II) complexes [Cu(N-N)2(X)]+, (N-N=substituted 1,10-phenanthroline derivatives and X=Cl- or NO3-), with tunable E1/2 for electrochemical reduction [CuII(N-N)2(X)]++1e-⇌[CuI(N-N)2]+X-. The disproportion of O2•- was explored in presence of the electro-generated species [CuI(N-N)2]+ using cyclic voltammetry in a non-aqueous media, arising a new simple method to propose a SOD-like mechanism, which can be used as a quick guide test for a compound, before being proven in biological assays. It was found that complexes with high negative half wave potential values (E1/2) for Cu(II)/Cu(I) couple shown a current increment for oxygen reduction, related to the capability of the disproportion of this reactive oxygen species.

The boundary of the ordinary e-pseudospectrum of a square matrix is contained in the boundary of the strict e-pseudospectrum. This content relation may be strict in some cases.

Porous Si-SiO2 UV microcavities are used to modulate a broad responsivity photodetector (GVGR-T10GD) with a detection range from 300 to 510 nm. The UV microcavity filters modified the responsivity at short wavelengths, while in the visible range the filters only attenuated the responsivity. All microcavities had a localized mode close to 360 nm in the UV-A range, and this meant that porous Si-SiO2 filters cut off the photodetection range of the photodetector from 300 to 350 nm, where microcavities showed low transmission. In the short-wavelength range, the photons were absorbed and did not contribute to the photocurrent. Therefore, the density of recombination centers was very high, and the photodetector sensitivity with a filter was lower than the photodetector without a filter. The maximum transmission measured at the localized mode (between 356 and 364 nm) was dominant in the UV-A range and enabled the flow of high energy photons. Moreover, the filters favored light transmission with a wavelength from 390 nm to 510 nm, where photons contributed to the photocurrent. Our filters made the photodetector more selective inside the specific UV range of wavelengths. This was a novel result to the best of our knowledge.

The effect of the gaseous atmosphere in the growth of gallium arsenide (GaAs) films was studied. The films have been grown by close-spaced vapor transport (CSVT) technique in a home-made hot filament chemical vapor deposition (HFCVD) reactor using molecular hydrogen and molecular nitrogen as the transport agent. An important point about the gaseous atmosphere is the ease in creating volatile compounds when it makes contact with the GaAs source, this favors the transport of material in a CSVT system. Chemical reactions are proposed in order to understand the significant difference produced from the gaseous atmosphere. The films grown with hydrogen are (almost) continuous and have homogeneous layers with preferential orientation (111). The films grown with nitrogen are granular and rough layers with the coexistence of the orientations (111), (220) and (311) in the crystals. The incorporation of impurities in the films was corroborated by energy dispersive spectroscopy (EDS) showing traces of oxygen and nitrogen for the case of the samples obtained with nitrogen. Films grown in a hydrogen atmosphere show a higher band gap than those grown in a nitrogen atmosphere. With the results of XRD and micro-Raman we observe a displacement and broadening of the peaks, characteristic of a structural disorder. The calculations of the FWHM allow us to observe the crystallinity degree and determine an approximate crystallite size using the Scherrer&rsquo, s equation.

Porous Si-SiO2 UV microcavities are used to modulate a broad responsivity photodetector (GVGR-T10GD) with a detection range from 300 to 510 nm. The UV microcavity filters modified the responsivity at short wavelengths, while in the visible range the filters only attenuated the responsivity. All microcavities had a localized mode close to 360 nm in the UV-A range, and this meant that porous Si-SiO2 filters cut off the photodetection range of the photodetector from 300 to 350 nm, where microcavities showed low transmission. In the short-wavelength range, the photons were absorbed and did not contribute to the photocurrent. Therefore, the density of recombination centers was very high, and the photodetector sensitivity with a filter was lower than the photodetector without a filter. The maximum transmission measured at the localized mode (between 356 and 364 nm) was dominant in the UV-A range and enabled the flow of high energy photons. Moreover, the filters favored light transmission with a wavelength from 390 nm to 510 nm, where photons contributed to the photocurrent. Our filters made the photodetector more selective inside the specific UV range of wavelengths. This was a novel result to the best of our knowledge.

Background: The enzymatic replacement therapy (ERT) availability for Gaucher disease (GD) has changed the landscape of the disease, several countries have screening programs. These actions have promoted the early diagnosis and avoided many complications in pediatric patients. In Spain ERT has been available since 1993 and 386 patients have been included in the Spanish Registry of Gaucher Disease (SpRGD). The aim of this study is to analyze the impact of ERT on the characteristics at time of diagnosis and initial complications in pediatric Gaucher disease patients. Aim: To analyze the impact of ERT on the characteristics at time of diagnosis and initial complications in pediatric Gaucher disease patients. Methods: A review of data in SpRGD from patients' diagnosed before 18 years old was performed. The cohort was split according the year of diagnosis (= 1995, cohort B). Results: A total of 98 pediatric patients were included, GD1: 80, GD3: 18; mean age: 7.2 (0.17-16.5) years, 58 (59.2%) males and 40 (40.8%) females. Forty-five were diagnosed = 1995. Genotype: N370S/N370S: 2 (2.0%), N370S/L444P: 27 (27.5%), N370S/other: 47 (48%), L444P/L444P: 7 (7.1%), L444P/D409H: 2 (2.0%), L444P/other: 3 (6.2%), other/other: 10 (10.2%). The mean age at diagnosis was earlier in patients diagnosed after 1995 (p < 0.001) and different between the subtypes, GD1: 8.2 (0.2-16.5) years and GD3: 2.8 (0.17-10.2) years (p < 0.001). There were more severe patients in the group diagnosed before 1994 (p = 0.045) carrying L444P (2), D409H (2), G377S (1), G195W (1) or the recombinant mutation. The patients' diagnosed = 1994 showed worse cytopenias, higher chance of bone vascular complications at diagnosis and previous spleen removal. The patients started ERT at a median time after diagnosis of 5.2 years [cohort A] and 1.6 years [cohort B] (p < 0.001). Conclusions: The early diagnosis of Gaucher disease in the era of ERT availability has permitted to reduce the incidence of severe and irreversible initial complication in pediatric patients, and this has permitted better development of these patients. This is the largest pediatric cohort from a national registry.

Let ( A , B ) ∈ C n × n × C n × m and M be an (A, B)-invariant subspace. Let C ( A , B ) be the controllability subspace of the pair (A, B). If M ∩ C ( A , B ) = M ∩ Im B , under additional hypotheses, necessary and sufficient conditions for the stability of the subspace M are given.

Cadmium sulfide/titanium dioxide (CdS/TiO2) composite films were grown on glass by the chemical bath deposition (DBQ) and sol-gel/dip coating methods, respectively, in order to increase the photocatalytic activity of TiO2 in photodegradation processes. The influence of the CdS deposition time on the morphology, optical absorption, and phononic modes of the composites were examined. Scanning electron microscopy (SEM) images showed clearly the CdS deposit on the TiO2 surface. The absorbance spectra indicated that the absorption of composites depends on the CdS deposition time and the absorption edges are shifted to the visible range. Micro Raman spectra exhibited the phonons associated with the TiO2 anatase and the longitudinal optic (LO) phonon of CdS whose intensity increases with the CdS deposition time. Photodegradation of methylene blue (MB) under visible light irradiation was observed in all films and the results were compared with those obtained with TiO2 films. The decomposition is higher for the composite with the CdS deposition time of 15 min. This optimal deposition time allows maximal enhancement of the charge carriers transfer to TiO2 involved in the photocatalysis. No signal associated with cadmium was detected by the atomic absorption spectroscopy (AAS), which means that the CdS photocorrosion does not occur since trap centers such as OH-Cd-S and Cl−, which trap holes and inhibit the photocorrosion, are produced during the growth process.

Let (A,B)∈ C n×n × C n×m . Suppose that the number of nonconstant (i.e., ≠1 ) invariant factors of the polynomial matrix λ[I n ,0]−[A,B] is less than k. For all complex number λ denote by σ n−(k−1) (λ[I n ,0]−[A,B]) the greatest (n−(k−1)) th singular value of the matrix λ[I n ,0]−[A,B] . The minimum absolute value of the real function of complex variable λ↦σ n−(k−1) (λ[I n ,0]−[A,B]) gives the distance from (A,B) to the set of pairs with more or equal number of nonconstant invariant factors. When k=1 , this specializes in the formula of Eising for the distance from a controllable pair (A,B) to the nearest uncontrollable pair. The complex numbers λ lying in the sublevel set {λ∈ C | σ n (λ[ I n , 0 ]−[ A , B ])⩽e} of the function λ↦σ n (λ[I n ,0]−[A,B]), are the uncontrollable modes of all the pairs that are within an e tolerance of (A,B) . All the results of this paper are an immediate consequence of the Singular Value Decomposition of a matrix and of the interpretation of the singular values as the distances to the nearest matrices of lower ranks.

Instituto de Física y Matemáticas. Maestría en Ciencias en el Área de Física From the perspective of the general theory of relativity, gravity is a manifestation of the curvature of space-time, which tells us that the dynamic state of a system is determined from the distribution of matter and vice versa; currently astrophysical processes involving the presence of strong gravitational fields produced by compact objects such as white dwarfs known, neutron stars and black holes, stars, all the product of the gravitational collapse of stars at some stage they have lost the fuel needed to counteract gravity. Therefore, an important tool in relativistic astrophysics is the understanding and management of the evolution of space-time matter is, it seems important to solve the Einstein equations in the presence of matter. It's certainly not a trivial issue, it requires the knowledge of the general theory of relativity and the decomposition 3 + 1 space-time and as the models are more realistic, the equations presented do not have an analytic solution as a ideally, then resort to numerical methods for a computer to do the calculations, and so be able to approximate the solution of a problem. This paper presents the necessary elements to evolve the process of accretion of an ideal gas in a spherically symmetric black hole, only radial flows, which would mean that the ideal gas moves radially towards the black hole, it will produce accrete matter and increase its size which will produce a change in the space-time. Desde la perspectiva de la teoría general de la relatividad, la gravedad es una manifestación de la curvatura del espacio-tiempo, lo cual nos dice que el estado dinámico de un sistema estará determinado a partir de la distribución de materia y viceversa; en la actualidad los procesos astrofísicos involucran la presencia de campos gravitacionales fuertes, producidos por objetos compactos como las estrellas conocidas como enanas blancas, estrellas de neutrones y agujeros negros, todos ellos producto del colapso gravitacional de estrellas en alguna fase en que se han quedado sin el combustible necesario para contrarrestar la gravedad. Por tanto, una herramienta importante en la astrofísica relativista es el conocimiento y manejo de la evolución de espacio-tiempo con materia es decir, parece importante saber resolver las ecuaciones de Einstein en presencia de materia. Desde luego no es un tema trivial, se requiere del conocimiento de la teoría general de la relatividad y la descomposición 3+1 del espacio-tiempo y conforme los modelos son más realistas, las ecuaciones que se presentan no tienen un solución analítica como en una situación ideal, entonces se recurre a los métodos numéricos para que una computadora haga los cálculos, y así ser capaces de aproximar la solución de algún problema. En este trabajo se presentan los elementos necesarios para evolucionar el proceso de acreción de un gas ideal en un hoyo negro esféricamente simétrico, con flujos radiales solamente, lo cual quiere decir que se supondría que el gas ideal se mueve radialmente hacia el agujero negro, lo cual producirá que éste acrete materia y aumente su tamaño lo cual producirá un cambio en el espacio-tiempo.

As a result of his consistent attitude as citizen and doctor and his “liberal spirit”, Marañón has gone down in the history of the twentieth century as an archetype. Marañón was, above all, a moralist in the Kantian sense, an autonomous person not governed by external criteria but by duty; a thinker convinced of the transforming role of the positive sciences, towards a happier and more just society through a deep intellectual reform. Marañón, like Fernando de los Rios, integrated Kraussism, neo-Kantianism and socialism and from this ideological platform sought the necessary moral change in the Spanish people., Marañón ha pasado a la historia del siglo XX como arquetipo, debido a su actitud coherente y a su “talante liberal”. Marañón fue, sobre todo, un moralista en el sentido kantiano. Una persona autónoma que no se rigió por criterios externos, sino por deber; un convencido del papel transformador de las ciencias positivas en pos de una sociedad más feliz y más justa gracias a una profunda reforma intelectual. Marañón, como Fernando de los Ríos, integró krausismo, neokantismo y socialismo y desde esa plataforma ideológica, propugnó el necesario cambio moral del pueblo español.

We study a homogeneous linear matrix equation system related to the strict equivalence of matrix pencils. We obtain the dimension of the vector space of its solutions in terms of the invariants of the strict equivalence. We give a characterization of the strict equivalence of matrix pencils by rank tests, and we extend Roth's criterion for the corresponding nonhomogeneous system.

The paper concerns the relation between the following two quantities. (i) The Holder condition number of an eigenvalue λ of a square complex matrix. (ii) The rate of growth of the diameter and the area of the connected component of the e-pseusospectrum containing λ.

This paper provides a new characterization of feedback equivalence that can be applied to controllable and noncontrollable matrix pairs $(A,B)$. This result is based on a generalization of a theorem of Rosenbrock describing the closed-loop invariant polynomials that are attainable by applying state feedback to a given system $\dot x = Ax + Bu$.

A new algorithm providing polynomial functions of several variables interpolating any values on given points is proposed. The obtained polynomials are more simpler, in degree and number of monomials, than other ones which have appeared in the literature.

In this paper we report the fabrication and experimental characterization of photoluminescent coupled multiple microcavity 1-Dimensional photonic bandgap structures for specific photonic applications. These structures have been prepared on silicon substrate as well as free standing. The comparision with theory gave a good fit showing desired structure formation for more than 184 layered structure. These structures can be useful for a large variety of applications such as silicon lasers.

AMS Classification: 15A18, 15A21, 15A60. Let G be a square complex matrix with less than k nonconstant invariant factors. We find a complex matrix that gives an optimal approximation to G among all possible matrices that have more than or equal to k invariant factors, obtained by varying only the entries of a bottom right submatrix of G. Supported by the Ministerio de Educación y Cultura (DGESIC), Proyecto PB97-0599-CO3-01.

Human Beings are respectable because they are Human Beings; not because they have the same worth or share the same beliefs. A new generation of human rights necessitates a new process of legitimization of political institutions. This is the essence of "Democracy and Bioethics". Life as we know it is under threat and from there emerges the importance of formulating a new table of human rights; ecological and environmental rights; the rights of different groups within society and the rights of future generations. These new rights are global and therefore demand a new type of democracy; it is this call for a global democracy, which must be discussed. Bioethics, in essence is a process of deliberation and discussion and therefore it is fitting that bioethics should provide the arena for discussion. It is important to realize that one day, deliberative democracy could be the reality, and be responsible for establishing a debate which reflects the diversity of ideas within society.

La Bioética, desde hace treinta años ha promovido incesantemente la participación democrática en el ámbito de la relación sanitaria, mediante procedimientos que permiten adoptar decisiones en las cuales se expresa el parecer y los intereses de todos los involucrados. Estos procedimientos dan cuenta de una práctica constante de deliberar en conjunto, con el fin de lograr las soluciones más matizadas y correctas. Esta experiencia de la Bioética permite plantear, de manera amplia, la relación entre Democracia y Bioética, en la medida que es necesario y urgente corregir los déficits democráticos, logrando que ésta no sólo sea participativa sino que también deliberativa