Tuning the aspect ratio of silver nanospheroids embedded in silica: erratum.

We present a corrigendum to our Letter [Opt. Lett.35, 703 (2010)10.1364/OL.35.000703]. In the original Letter we inadvertently included in Fig. 2(a) a TEM micrograph corresponding to a different, but very similar, sample. This corrigendum replaces Fig. 2(a) with a correct version. Since the main results are rather based in optical absorption measurements, and their modeling by using the T-matrix method, this correction does not affect the results and conclusions of the original Letter.

Cleavage and activation of LIM kinase 1 as a novel mechanism for calpain 2-mediated regulation of nuclear dynamics.

Calpain-2 (CAPN2) is a processing enzyme ubiquitously expressed in mammalian tissues whose pleiotropic functions depend on the role played by its cleaved-products. Nuclear interaction networks, crucial for a number of molecular processes, could be modified by CAPN2 activity. However, CAPN2 functions in cell nucleus are poorly understood. To unveil CAPN2 functions in this compartment, the result of CAPN2-mediated interactions in cell nuclei was studied in breast cancer cell (BCC) lines. CAPN2 abundance was found to be determinant for its nucleolar localization during interphase. Those CAPN2-dependent components of nucleolar proteome, including the actin-severing protein cofilin-1 (CFL1), were identified by proteomic approaches. CAPN2 binding, cleavage and activation of LIM Kinase-1 (LIMK1), followed by CFL1 phosphorylation was studied. Upon CAPN2-depletion, full-length LIMK1 levels increased and CFL1/LIMK1 binding was inhibited. In addition, LIMK1 accumulated at the cell periphery and perinucleolar region and, the mitosis-specific increase of CFL1 phosphorylation and localization was altered, leading to aberrant mitosis and cell multinucleation. These findings uncover a mechanism for the role of CAPN2 during mitosis, unveil the critical role of CAPN2 in the interactions among nuclear components and, identifying LIMK1 as a new CAPN2-target, provide a novel mechanism for LIMK1 activation. CFL1 is crucial for cytoskeleton remodeling and mitosis, but also for the maintenance of nuclear structure, the movement of chromosomes and the modulation of transcription frequently altered in cancer cells. Consequently, the role of CAPN2 in the nuclear compartment might be extended to other actin-associated biological and pathological processes.

Enhanced ultrafast optomagnetic effects in room-temperature ferromagnetic Pt nanoclusters embedded in silica by ion implantation.

Ferromagnetic-like behavior at room temperature (300 K) was observed in Pt particles embedded in ion-implanted silica matrices. Results in samples integrated by ultra-small photoluminescent Pt clusters (<2 nm) were compared with samples containing exclusively larger plasmonic Pt nanoparticles (>3 nm). The ferromagnetic behavior coexists simultaneously with a diamagnetic response. Enhanced diamagnetic response of one order of magnitude was observed compared to typical diamagnetism in pure silica, and it is increased with the mean diameter of the Pt particles. Besides, a larger sensitivity to an external field was observed in the ferromagnetic response of the nanostructures with a characteristic saturation at 20 kOe. This ferromagnetic behavior was only observed in the samples with nucleated Pt particles. The magnitude of the saturation magnetization shows up to a fivefold increase in the samples with smaller particle size and larger particle density. Saturation magnetization was observed between 3-15 × 10-4 emu g-1, with remanent magnetization of 0.2-0.6 × 10-4emu g-1, measured at 300 K. Coercitive fields also decrease in samples with smaller size and particles density, with values of 114 and 300 Oe. At lower temperatures (5 K) the saturation magnetization increases, as it would be expected from a ferromagnetic state. Optomagnetic response was studied by inverse Faraday effects and induced photomagnetization with circular polarized picosecond pulsed light at 1064 nm wavelength. Results showed that samples with a stronger ferromagnetic response exhibit larger Faraday rotation up to 5.3 × 103deg cm-1 by light excitations with irradiances between 50 and 180 GW cm-2. These findings have immediate applications in multifunctional solid-state magneto-optical devices such as optical isolators, high-data storage devices and ultrafast all-optical switching of magnetization.

Surface morphology of amorphous SiO2 substrates bombarded with 1.0 MeV Si+ ions.

Surface pattern formation on amorphous SiO2 substrates by implantation of 1.0 MeV Si+ ions at a current of 1.3 µA at 70° angle is reported. Surface micrometer sized ripples perpendicular to the ion beam direction are formed, observed by scanning electron microscopy and atomic force microscopy. The morphological features are more or less similar for different fluences. The formation of surface ripples at this energy is discussed in terms of ion stopping mechanisms and patterns obtained within the low- and medium-energy ranges.

Breakdown of the coherence effects and Fermi liquid behavior in YbAl3 nanoparticles.

A change in the Kondo lattice behavior of bulk YbAl3 has been observed when the alloy is shaped into nanoparticles (≈12 nm). Measurements of the electrical resistivity show inhibited coherence effects and deviation from the standard Fermi liquid behavior (T 2-dependence). These results are interpreted as being due to the effect of the disruption of the periodicity of the array of Kondo ions provoked by the size reduction process. Additionally, the ensemble of randomly placed nanoparticles also triggers an extra source of electronic scattering at very low temperatures (≈15 K) due to quantum interference effects.

Reliability of the MDi Psoriasis® Application to Aid Therapeutic Decision-Making in Psoriasis. / Fiabilidad de una aplicación de ayuda a la toma de decisiones terapéuticas en el paciente con psoriasis (MDi Psoriasis®).

BACKGROUND: Therapeutic decisions in psoriasis are influenced by disease factors (e.g., severity or location), comorbidity, and demographic and clinical features. OBJECTIVE: We aimed to assess the reliability of a mobile telephone application (MDi-Psoriasis) designed to help the dermatologist make decisions on how to treat patients with moderate to severe psoriasis. METHOD: We analyzed interobserver agreement between the advice given by an expert panel and the recommendations of the MDi-Psoriasis application in 10 complex cases of moderate to severe psoriasis. The experts were asked their opinion on which treatments were most appropriate, possible, or inappropriate. Data from the same 10 cases were entered into the MDi-Psoriasis application. Agreement was analyzed in 3 ways: paired interobserver concordance (Cohen's κ), multiple interobserver concordance (Fleiss's κ), and percent agreement between recommendations. RESULTS: The mean percent agreement between the total of 1210 observations was 51.3% (95% CI, 48.5-54.1%). Cohen's κ statistic was 0.29 and Fleiss's κ was 0.28. Mean agreement between pairs of human observers only, excluding the MDi-Psoriasis recommendations, was 50.5% (95% CI, 47.6-53.5%). Paired agreement between the recommendations of the MDi-Psoriasis tool and the majority opinion of the expert panel (Cohen's κ) was 0.44 (68.2% agreement). CONCLUSIONS: The MDi-Psoriasis tool can generate recommendations that are comparable to those of experts in psoriasis.

Magnetic phase diagram of superantiferromagnetic TbCu2 nanoparticles.

The structural state and static and dynamic magnetic properties of TbCu2 nanoparticles are reported to be produced by mechanical milling under inert atmosphere. The randomly dispersed nanoparticles as detected by TEM retain the bulk symmetry with an orthorhombic Imma lattice and Tb and Cu in the 4e and 8h positions, respectively. Rietveld refinements confirm that the milling produces a controlled reduction of particle sizes reaching ≃6 nm and an increase of the microstrain up to ≃0.6%. The electrical resistivity indicates a metallic behavior and the presence of a magnetic contribution to the electronic scattering which decreases with milling times. The dc-susceptibility shows a reduction of the Néel transition (from 49 K to 43 K) and a progressive increase of a peak (from 9 K to 15 K) in the zero-field-cooled magnetization with size reduction. The exchange anisotropy is very weak (a bias field of ≃30 Oe) and is due to the presence of a disordered (thin) shell coupled to the antiferromagnetic core. The dynamic susceptibility evidences a critical slowing down in the spin-disordered state for the lowest temperature peak associated with a spin glass-like freezing with a tendency of zv and ß exponents to increase when the size becomes 6 nm (zv ≃ 6.6 and ß ≃ 0.85). A Rietveld analysis of the neutron diffraction patterns 1.8 ≤ T ≤ 60 K, including the magnetic structure determination, reveals that there is a reduction of the expected moment (≃80%), which must be connected to the presence of the disordered particle shell. The core magnetic structure retains the bulk antiferromagnetic arrangement. The overall interpretation is based on a superantiferromagnetic behavior which at low temperatures coexists with a canting of surface moments and a mismatch of the antiferromagnetic sublattices of the nanoparticles. We propose a novel magnetic phase diagram where changes are provoked by a combination of the decrease of size and the increase of microstrain.

Nanoparticle containing channel waveguides produced by a multi-energy masked ion-implantation process.

We present the fabrication and characterization of channel waveguides based on composites containing silver nanoparticles. The substrate employed is silica and the nanoparticles were produced by a masked ion-implantation technique. Multiple implantation processes were made at different energies in order to produce waveguides with an appropriate width. We also present results for the characterization of the waveguiding properties of the devices produced.

[Evaluation of isometric force in lower limbs and body composition in preterm infants]. / Valoración de fuerza isométrica en extremidades inferiores y composición corporal en prematuros.

INTRODUCTION: Strength is a physical quality with a clear influence on quality of life. It is determined by the structure of the musculoskeletal system, and depends on the muscular structure. It has been described that prematurity conditions both qualities. The aims of this study are to determine whether prematurity is associated with strength or body composition and evaluate the relationship between prematurity, strength and muscle mass. MATERIAL AND METHODS: Case-control study. Participants were premature 7-to-11 year-old children and full-term birth controls. Strength was measured by a strength gauge and body composition from DEXA (duel-energy X-ray absorptiometry) scans. A total of 89 subjects were included and divided into three groups: 30 prematures with birth-weight ≤ 1500g, 29 prematures with birth-weight 1500-2000g, and 30 controls. RESULTS: Weight and BMI z-score was lower in the premature group. No differences were found in muscular mass or strength between groups. A ratio was established between strength and weight or muscular mass. It was observed that it was possible for them to move four times their weight, without finding any differences between groups or a relationship with birth-weight. CONCLUSIONS: Between 7 and 11 years of age, children who were premature have lower weight and BMI than the rest of the children. However, there were no differences in body composition or strength between preterm children and controls.

[Treatment of obesity in a hospital endocrinology clinic. Influence of parental body mass index]. / Tratamiento de la obesidad en la consulta de endocrinología de un hospital. Influencia del índice de masa corporal de los padres.

INTRODUCTION: Parental obesity is a risk factor for childhood obesity. The aim of this study was to determine if parental obesity influences the adherence and success of obesity treatment in a hospital paediatric endocrinology clinic. MATERIAL AND METHODS: An analytical, prospective, longitudinal study was conducted on obese children aged 4-14. An initial body mass index (BMI), and again at 6 months after receiving health, hygiene and dietary recommendations. Success was considered as a decrease of 0.5 in the BMI Z-score, and adherence to attending the 6-month review. Parental BMI was determined to identify overweight. The χ(2) test was used for qualitative variables and the T-Student test for quantitative (significance, p<<.05). RESULTS: The study included 100 children (52 male), 9.9±2.7 years old, BMI 28.1± 4.5kg/m(2) and BMI Z-Score 3.11±0.98. (85% had a BMI Z-score>3). More than half (59%) of the children had one or both parents obese (41 fathers and 37 mothers were obese). Treatment was not adhered to by 25 children. Adherence was worse if both parents were obese OR 3.65 (1.3 to 10.5) (P<=.01) and adherence was better if the mother was not obese, although the father was (P=.01). The treatment had significant success in 40 patients. If the mother was the only obese one in the family, the possibility of treatment failure was greater OR 5.6 (1.4 to 22.4) (P<.01) CONCLUSIONS: A high percentage of children with severe obesity have obese parents. The mother has an important influence on adherence and response to treatment for the severely obese child.

[Amount of sleep and changes in its patterns in children less than two years old]. / Cuantificación del sueño y presencia de alteraciones en la duración del sueño en niños menores de 2 años.

OBJECTIVES: The aim is to study the sleep duration and the 24-hour sleep distribution pattern in children under 2 years-old from two different areas of Spain, as well as to determine the prevalence of abnormal sleep duration and the influence of age on this prevalence, and compare them with the already published data. MATERIAL AND METHODS: An observational, descriptive and cross-sectional study on children from two health centers: one in Castilla y León and the other in Asturias. Their parents completed the Brief Infant Sleep Questionnaire (BISQ). Daytime and nighttime sleep duration was assessed, with percentiles being used to evaluate the results. Two groups were created: one according to the age (children under or above 6 months), and the other according to the area. RESULTS: A total of 125 children were studied (73 males). The nighttime sleep duration increased from 8.28±2.06 hours to 10.43±1.21 hours (P=.0001) and the daytime sleep decreased from 4.61±2.66 to 1.96±0.79 hours (P=.0001) for children under 6 months and above 6 months, respectively. The children from Castilla y León slept more during daytime than those from Asturias (3.91±2.67 vs 3.00±2.09 hours, P=.041). Nineteen children had a total sleep duration below the 2nd percentile. A sleep duration below normal percentiles was observed in children under 6 months (14/72 vs 5/53, P=.006). CONCLUSIONS: As children grow older, they substitute daytime sleep for nighttime sleep. Approximately 15% of the children under 2 years-old may have changes in sleep duration, and is more common in children under 6 months.