Influence of the Difference Between Corneal and Refractive Astigmatism on LASIK Outcomes Using Solid-State Technology

Purpose: To evaluate the influence of the difference between preoperative corneal and refractive astigmatism [ocular residual astigmatism (ORA)] on outcomes obtained after laser in situ keratomileusis (LASIK) surgery for correction of myopic astigmatism using the solid-state laser technology. Methods: One hundred one consecutive eyes with myopia or myopic astigmatism of 55 patients undergoing LASIK surgery using the Pulzar Z1 solid-state laser (CustomVis Laser Pty Ltd, currently CV Laser) were included. Visual and refractive changes at 6 months postoperatively and changes in ORA and anterior corneal astigmatism and posterior corneal astigmatism (PCA) were analyzed. Results: Postoperatively, uncorrected distance visual acuity improved significantly (P < 0.01). Likewise, refractive cylinder magnitude and spherical equivalent were reduced significantly (P < 0.01). In contrast, no significant changes were observed in ORA magnitude (P = 0.81) and anterior corneal astigmatism (P = 0.12). The mean overall efficacy and safety indices were 0.96 and 1.01, respectively. These indices were not correlated with preoperative ORA (r = −0.15, P = 0.15). Furthermore, a significant correlation was found between ORA (r = 0.81, P < 0.01) and PCA postoperatively, but not preoperatively (r = 0.12, P = 0.25). Likewise, a significant correlation of ORA with manifest refraction was only found postoperatively (r = −0.38, P < 0.01). Conclusions: The magnitude of ORA does not seem to be a predictive factor of efficacy and safety of myopic LASIK using a solid-state laser platform. The higher relevance of PCA after surgery in some cases may explain the presence of unexpected astigmatic residual refractive errors.

A qualitative exploration of the impact of the economic recession in Spain on working, living and health conditions: reflections based on immigrant workers' experiences

Background: This study aimed to analyse how immigrant workers in Spain experienced changes in their working and employment conditions brought about Spain's economic recession and the impact of these changes on their living conditions and health status. Method: We conducted a grounded theory study. Data were obtained through six focus group discussions with immigrant workers (n = 44) from Colombia, Ecuador and Morocco, and two individual interviews with key informants from Romania living in Spain, selected by theoretical sample. Results: Three categories related to the crisis emerged – previous labour experiences, employment consequences and individual consequences – that show how immigrant workers in Spain (i) understand the change in employment and working conditions conditioned by their experiences in the period prior to the crisis, and (ii) experienced the deterioration in their quality of life and health as consequences of the worsening of employment and working conditions during times of economic recession. Conclusion: The negative impact of the financial crisis on immigrant workers may increase their social vulnerability, potentially leading to the failure of their migratory project and a return to their home countries. Policy makers should take measures to minimize the negative impact of economic crisis on the occupational health of migrant workers in order to strengthen social protection and promote health and well-being.

Racism, Other Discriminations and Effects on Health

We study the probability of perceived racism/other forms of discrimination on immigrant and Spanish populations within different public spheres and show their effect on the health of immigrants using a cross-sectional design (ENS-06). Variables: perceived racism/other forms of discrimination (exposure), socio-demographic (explicative), health indicators (dependent). Frequencies, prevalences, and bivariate/multivariate analysis were conducted separately for men (M) and women (W). We estimated the health problems attributable to racism through the population attributable proportion (PAP). Immigrants perceived more racism than Spaniards in workplace (ORM = 48.1; 95 % CI 28.2–82.2), and receiving health care (ORW = 48.3; 95 % CI 24.7–94.4). Racism and other forms of discrimination were associated with poor mental health (ORM = 5.6; 95 % CI 3.9–8.2; ORW = 7.3; 95 % CI 4.1–13.0) and injury (ORW = 30.6; 95 % CI 13.6–68.7). It is attributed to perceived racism the 80.1 % of consumption of psychotropics (M), and to racism with other forms of discrimination the 52.3 % of cases of injury (W). Racism plays a role as a health determinant.

Open access, repositorios, directorios de repositorios y open licenses

Este trabajo aborda el tema del acceso abierto (open access) de la literatura científica. Se analizan las declaraciones sobre las que se basan sus cimientos y las estrategias existentes para la difusión del conocimiento. Así mismo, se tratan las iniciativas que colaboran con este fin: los repositorios, los directorios de repositorios de acceso abierto y las licencias abiertas (open licenses). Por último, se pone de manifiesto la relación que existe entre el movimiento de acceso abierto y las iniciativas relacionadas con los recursos educativos abiertos.

La influencia normativa y de los propietarios del suelo en la formación del barrio de Benalúa, Alicante (1883)

El presente artículo plantea el doble objetivo de subsanar, por un lado, el vacío documental existente en relación a cómo influyeron los condicionantes sociopolíticos y económicos, normativas del momento y exigencias de los propietarios del suelo en la concepción del singular barrio de Benalúa de Alicante (España), proyectado por el arquitecto José Guardiola Picó (1883); y, por otro, difundir en el ámbito internacional el conocimiento de esta actuación relevante que, anticipándose a la ejecución del ensanche de la ciudad (1898), encabezó los primeros intentos de industrialización y control del crecimiento urbano, para que sirva de base a futuras investigaciones y estudios comparativos con actuaciones semejantes de Europa y América. De la exposición se concluyen las cualidades e identidad de un barrio pionero en atender, por iniciativa particular y de modo sectorial, la necesidad higienista y reflexión urbanística que precisaba la ciudad, reflejo de la calidad arquitectónica manifiesta desde su proyecto. Asimismo, el porqué de la aparición de ciertas variaciones dimensionales en la coherencia de su trazado, el origen de la parcela y manzana tipo que lo configuraron y otras influencias en el programa y diseño de la vivienda, que sólo pueden explicarse desde regulaciones e intereses externos a la propia génesis proyectual. Reflexiones que constatan las claves del proyecto que confirieron al barrio la capacidad de asumir, sin perder su cualidad, los sucesivos procesos de adaptación y transformación impuestos.

Hydrogen Production by Steam Reforming of Ethanol on Rh-Pt Catalysts: Influence of CeO2, ZrO2, and La2O3 as Supports

CeO2-, ZrO2-, and La2O3-supported Rh-Pt catalysts were tested to assess their ability to catalyze the steam reforming of ethanol (SRE) for H2 production. SRE activity tests were performed using EtOH:H2O:N2 (molar ratio 1:3:51) at a gaseous space velocity of 70,600 h−1 between 400 and 700 °C at atmospheric pressure. The SRE stability of the catalysts was tested at 700 °C for 27 h time on stream under the same conditions. RhPt/CeO2, which showed the best performance in the stability test, also produced the highest H2 yield above 600 °C, followed by RhPt/La2O3 and RhPt/ZrO2. The fresh and aged catalysts were characterized by TEM, XPS, and TGA. The higher H2 selectivity of RhPt/CeO2 was ascribed to the formation of small (~5 nm) and stable particles probably consistent of Rh-Pt alloys with a Pt surface enrichment. Both metals were oxidized and acted as an almost constant active phase during the stability test owing to strong metal-support interactions, as well as the superior oxygen mobility of the support. The TGA results confirmed the absence of carbonaceous residues in all the aged catalysts.

Real-time monitoring of electrochemically active biofilm developing behavior on bioanode by using EQCM and ATR/FTIR

In the current study, the relationship between current and biomass and bio-adhesion mechanism of electrogenic biofilm on electrode were investigated using EQCM and ATR-SEIRAS linking electrochemistry. The results indicated that cellular biomass of biofilm on QCM-crystal surface showed maximum value of 6.0 μg/cm2 in initial batch and 11.5 μg/cm2 in the second batch on mature biofilm, producing a similar maximum current density of 110 μA/μg. Especially, the optimum cell biomass linking high electricity production ratio (110 μA/μg) occurred before maximum biomass coming, implying that over-growth mature biofilm is not an optimum state for enhancing power output of MFCs. On the other hand, the spectra using ATR-SEIRAS technique linking electrochemistry obviously exhibited water structure adsorption change at early biofilm formation and meanwhile the water adsorption accompanied the adsorbed bacteria and the bound cells population on the electrode increased with time. Meanwhile, the direct contact of bacteria and electrode via outer-membrane protein can be confirmed via a series spectra shift at amide I and amide II modes and water movement from negative bands displacing by adsorbed bacteria. Our study provided supplementary information about the interaction between the microbes and electrode beyond traditional electrochemistry.

Imaging of spin waves in atomically designed nanomagnets

The spin dynamics of all ferromagnetic materials are governed by two types of collective phenomenon: spin waves and domain walls. The fundamental processes underlying these collective modes, such as exchange interactions and magnetic anisotropy, all originate at the atomic scale. However, conventional probing techniques based on neutron1 and photon scattering2 provide high resolution in reciprocal space, and thereby poor spatial resolution. Here we present direct imaging of standing spin waves in individual chains of ferromagnetically coupled S = 2 Fe atoms, assembled one by one on a Cu2N surface using a scanning tunnelling microscope. We are able to map the spin dynamics of these designer nanomagnets with atomic resolution in two complementary ways. First, atom-to-atom variations of the amplitude of the quantized spin-wave excitations are probed using inelastic electron tunnelling spectroscopy. Second, we observe slow stochastic switching between two opposite magnetization states3, 4, whose rate varies strongly depending on the location of the tip along the chain. Our observations, combined with model calculations, reveal that switches of the chain are initiated by a spin-wave excited state that has its antinodes at the edges of the chain, followed by a domain wall shifting through the chain from one end to the other. This approach opens the way towards atomic-scale imaging of other types of spin excitation, such as spinon pairs and fractional end-states5, 6, in engineered spin chains.

Development and programming of Geophonino: A low cost Arduino-based seismic recorder for vertical geophones

The commercial data acquisition systems used for seismic exploration are usually expensive equipment. In this work, a low cost data acquisition system (Geophonino) has been developed for recording seismic signals from a vertical geophone. The signal goes first through an instrumentation amplifier, INA155, which is suitable for low amplitude signals like the seismic noise, and an anti-aliasing filter based on the MAX7404 switched-capacitor filter. After that, the amplified and filtered signal is digitized and processed by Arduino Due and registered in an SD memory card. Geophonino is configured for continuous registering, where the sampling frequency, the amplitude gain and the registering time are user-defined. The complete prototype is an open source and open hardware system. It has been tested by comparing the registered signals with the ones obtained through different commercial data recording systems and different kind of geophones. The obtained results show good correlation between the tested measurements, presenting Geophonino as a low-cost alternative system for seismic data recording.