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In recent years, about 150 low-mass white dwarfs (WDs), typically with masses below 0.4 M⊙, have been discovered. The majority of these low-mass WDs are observed in binary systems as they cannot be formed through single-star evolution within Hubble time. In this work, we present a comprehensive analysis of the double low-mass WD eclipsing binary system J2102−4145. Our investigation encompasses an extensive observational campaign, resulting in the acquisition of approximately 28 h of high-speed photometric data across multiple nights using NTT/ULTRACAM, SOAR/Goodman, and SMARTS-1m telescopes. These observations have provided critical insights into the orbital characteristics of this system, including parameters such as inclination and orbital period. To disentangle the binary components of J2102−4145, we employed the XTGRID spectral fitting method with GMOS/Gemini-South and X-shooter data. Additionally, we used the PHOEBE package for light curve analysis on NTT/ULTRACAM high-speed time-series photometry data to constrain the binary star properties. Our analysis unveils remarkable similarities between the two components of this binary system. For the primary star, we determine Teff,1 = 13 688−72+65 K, log g1 = 7.36 ± 0.01, R1 = 0.0211 ± 0.0002 R⊙, and M1 = 0.375 ± 0.003 M⊙, while, the secondary star is characterised by Teff,2 = 12952−66+53 K, log g2 = 7.32 ± 0.01, R2 = 0.0203−0.0003+0.0002 R⊙, and M2 = 0.314 ± 0.003 M⊙. Furthermore, we found a notable discrepancy between Teff and R of the less massive WD, compared to evolutionary sequences for WDs from the literature, which has significant implications for our understanding of WD evolution. We discuss a potential formation scenario for this system which might explain this discrepancy and explore its future evolution. We predict that this system will merge in ∼800 Myr, evolving into a helium-rich hot subdwarf star and later into a hybrid He/CO WD. [ABSTRACT FROM AUTHOR]

Object recognition is a complex cognitive process that relies on how the brain organizes object-related information. While spatial principles have been extensively studied, less studied temporal dynamics may also offer valuable insights into this process, particularly when neural processing overlaps for different categories, as it is the case of the categories of hands and tools. Here we focus on the differences and/or similarities between the time-courses of hand and tool processing under electroencephalography (EEG). Using multivariate pattern analysis, we compared, for different time points, classification accuracy for images of hands or tools when compared to images of animals. We show that for particular time intervals (~ 136–156 ms and ~ 252–328 ms), classification accuracy for hands and for tools differs. Furthermore, we show that classifiers trained to differentiate between tools and animals generalize their learning to classification of hand stimuli between ~ 260–320 ms and ~ 376–500 ms after stimulus onset. Classifiers trained to distinguish between hands and animals, on the other hand, were able to extend their learning to the classification of tools at ~ 150 ms. These findings suggest variations in semantic features and domain-specific differences between the two categories, with later-stage similarities potentially related to shared action processing for hands and tools. [ABSTRACT FROM AUTHOR]

We report the detection of periodic variations on the |$T_\mathrm{eff}\simeq 32\, 000$|  K DA white dwarf star HE 1017−1352. We obtained time series photometry using the 4.1-m Southern Astrophysical Research telescope on three separate nights for a total of 16.8 h. From the frequency analysis, we found four periods of 605, 556, 508, and 869 s with significant amplitudes above the 1/1000 false alarm probability detection limit. The detected modes are compatible with low harmonic degree g-mode non-radial pulsations with radial order higher than ∼9. This detection confirms the pulsation nature of HE 1017−1352 and thus the existence of the new pulsating class of hot DA white dwarf stars. In addition, we detect a long period of 1.52 h, compatible with a rotation period of DA white dwarf stars. [ABSTRACT FROM AUTHOR]

We perform ground-based photometric observations of 22 DA white dwarf stars, 10 already known ZZ Cetis and 12 candidates with atmospheric parameters inside the classical instability strip. We report on the discovery of four new variable DA white dwarf stars. Two objects are near the middle of the instability strip, SDSS J082804.63+094956.6 and SDSS J094929.09+101918.8, and two red edge pulsators, GD 195 and L495−82. In addition, we classified four objects as possible variables, since evidence of variability was detected in the light curve, but the signal-to-noise ratio was not sufficient to establish a definite detection. Follow-up observations were performed for 10 known ZZ Ceti stars to verify period stability and search for new periodicities. For each confirmed variable, we perform a detailed asteroseismological fit and compare the structural parameters obtained from the best-fitting models with those obtained from spectroscopy and photometry from Gaia. Finally we present a study of the asteroseismological properties of a sample of 91 ZZ Ceti stars. [ABSTRACT FROM AUTHOR]

We investigated the optical absorption of the fundamental band edge and the origin of the emission from β-FeSi2 nanoparticles synthesized by ion-beam-induced epitaxial crystallization of Fe+ implanted SiO2/Si(100) followed by thermal annealing. From micro-Raman scattering and transmission electron microscopy measurements it was possible to attest the formation of strained β-FeSi2 nanoparticles and its structural quality. The optical absorption near the fundamental gap edge of β-FeSi2 nanoparticles evaluated by spectroscopic ellipsometry showed a step structure characteristic of an indirect fundamental gap material. Photoluminescence spectroscopy measurements at each synthesis stage revealed complex emissions in the 0.7–0.9 eV spectral region, with different intensities and morphologies strongly dependent on thermal treatment temperature. Spectral deconvolution into four transition lines at 0.795, 0.809, 0.851, and 0.873 eV was performed. We concluded that the emission at 0.795 eV may be related to a radiative direct transition from the direct conduction band to an acceptor level and that the emission at 0.809 eV derives from a recombination of an indirect bound exciton to this acceptor level of β-FeSi2. Emissions 0.851 and 0.873 eV were confirmed to be typical dislocation-related photoluminescence centers in Si. From the energy balance we determined the fundamental indirect and direct band gap energies to be 0.856 and 0.867 eV, respectively. An illustrative energy band diagram derived from a proposed model to explain the possible transition processes involved is presented. [ABSTRACT FROM AUTHOR]

In this work we present a study of photoluminescence (PL) on Si nanocrystals (NC) produced by ion implantation on SiO2 targets at temperatures ranging between room temperature and 800 °C and subsequently annealed in N2 atmosphere. The PL measurements were performed at low excitation power density (20 mW/cm2) in order to avoid nonlinear effects. Broad PL spectra were obtained, presenting a line-shape structure that can be reproduced by two superimposed peaks at around 780 and 950 nm. We have observed that both PL intensity and line-shape change by varying the annealing as well as the implantation temperatures. Implantations performed at 400 °C or higher produce a remarkable effect in the PL line shape, evidenced by a strong redshift, and a striking intensity increase of the peak located at the long-wavelength side of the PL spectrum. In addition we have studied the PL dependence on the excitation power density (from 0.002 to 15 W/cm2). The samples with broad NC size distribution containing large grains, as revealed by transmission electron microscopy observations presented a PL spectrum whose line shape was strongly dependent on the excitation power density. While high excitation power densities (saturation regime) induce only the short-wavelength part of the PL spectrum, low excitation power densities bring out the appearance of the hidden long-wavelength part of the emission. The present results are explained by current models. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • [Emim][MeSO 3 ] is used as electrolyte additive for HER in 25–85 °C temperature range. • [Emim][MeSO 3 ] addition accelerates H 2 evolution rate at temperatures up to 45 °C. • IL-addition leads to higher exchange current density and lower HER activation energy. • Significant decrease of impedance is observed in presence of the IL below 45 °C. Abstract Use of room-temperature ionic liquids (RTILs) as electrolyte additives for highly efficient alkaline water electrolysis at low temperatures is evaluated. The hydrogen evolution reaction (HER) was studied with platinum cathode in 8 M KOH solution with and without addition of 2 vol.% of [Emim][MeSO 3 ] in the 25–85 °C temperature range using voltammetry, chronoamperometry and electrochemical impedance spectroscopy measurements. Catalytic effect of IL's presence in the electrolyte is evidenced for temperatures up to 45 °C by an increase of the exchange current density values, as well as a significant decrease of the overall impedance in the entire potential range. Thus, a lower activation energy of 38 kJ mol−1 is determined for HER in IL-added KOH compared to that of 48 kJ mol−1 for HER in IL-free KOH. [ABSTRACT FROM AUTHOR]

We introduce a model for the execution of large market orders in limit order books, and use a linear combination of self-exciting Hawkes processes to model asset-price dynamics, with the addition of a price-impact function that is concave in the order size. A criterion for a general price-impact function is introduced, which is used to show how specification of a concave impact function affects order execution. Using our model, we examine the immediate and permanent impacts of large orders, analyse the potential for price manipulation, and show the effectiveness of the time-weighted average price strategy. Our model shows that price depends on the balance between the intensities of the Hawkes process, which can be interpreted as a dependence on order-flow imbalance. [ABSTRACT FROM AUTHOR]

Addresses the important parameters which can influence the radiation induced diffusion mechanism of xenon ions implanted into a photoresist film. Overview of the trapping-detrapping mechanism of the radiation induced diffusion process; Role of nuclear energy transfer in the radiation induced diffusion mechanism; Results of the argon bomabardment experiments.

Presents a study which examined the recrystallization via solid phase epitaxial growth of amorphized silicon layers implanted with iron. Observation of the push-out of iron atoms; Experimental methods; Results and discussion.

Examines the effects of ion bombardment on the phase equilibria and ordering of iron-nickel alloys. Details on the experiment; Results of the study; Conclusions.

Presents information on a study that examined the effects of xenon bombardment on carbonitrides produced by nitrogen implantation in a low-carbon steel via conversion electron Mössbauer spectroscopy and nuclear reaction analysis. Dissolution of the produced carbonitrides; Modification of the thermal behavior of the precipitates; Irradiation with argon ions.

Deals with a study which used the Rutherford backscattering technique to determine the range parameters of Bi ions implanted into AZ111 photoresist film at energies from ten to 400 keV. Experimental procedure and data analysis; Results and discussion; Conclusions.

Different subsets of asthma patients may be recognized according to the exposure trigger and the frequency and severity of clinical signs and symptoms. Regarding the exposure trigger, generally asthma can be classified as allergic (or atopic) and nonallergic (or nonatopic). Allergic and nonallergic asthma are distinguished by the presence or absence of clinical allergic reaction and in vitro IgE response to specific aeroallergens. The mechanisms of allergic asthma have been extensively studied with major advances in the last two decades. Nonallergic asthma is characterized by its apparent independence from allergen exposure and sensitization and a higher degree of severity, but little is known regarding the underlying mechanisms. Clinically, allergic and nonallergic asthma are virtually indistinguishable in exacerbations, although exacerbation following allergen exposure is typical of allergic asthma. Although they both show several distinct clinical phenotypes and different biomarkers, there are no ideal biomarkers to stratify asthma phenotypes and guide therapy in clinical practice. Nevertheless, some biomarkers may be helpful to select subsets of atopic patients which might benefit from biologic agents, such as omalizumab. Patients with severe asthma, uncontrolled besides optimal treatment, notwithstanding nonatopic, may also benefit from omalizumab therapy, although currently there are no randomized double-blind placebo controlled clinical trials to support this suggestion. However, omalizumab discontinuation according to each patient’s response to therapy and pharmacoeconomical analysis are questions that remain to be answered. [ABSTRACT FROM AUTHOR]

X Fragile Syndrome is pointed as the greatest cause of inherited mental retardation and the second most common genetic cause of mental retardation. It reaches all ethnic groups and races, but with low prevalence. It is estimated that one on every 1000 male births carries the syndrome and that one on every 2000 female born alive is affected. Although not specific, numerous physical and cognitive changes may be related to the syndrome, such as mental deficiency, facial dysmorphism and behavioral changes. This study aimed to briefly review the available literature about X Fragile Syndrome and present a case report of a newborn diagnosed with the disease. Thus, Brazilian databases were consulted and, to assist in the diagnosis of other individuals who may have the syndrome, an ethics committee approved the clinical report in order to bring public initial symptomatology, clinical exams and evolution of a patient with X Fragile Syndrome. It is necessary to acquire the syndrome's diagnosis as soon as possible, since it has no cure and the treatment consists of improving and prolonging the quality of life of the affected patient. Genetic counseling is also indicated in most cases to prevent further onset of the syndrome. [ABSTRACT FROM AUTHOR]

Developing novel and efficient electrocatalysts is vital to overcome most of the technical and economic issues associated with the hydrogen production via water electrolysis. Herein, Pd-based alloy nanoparticles, namely AuPd and FePd, assembled on reduced graphene oxide (rGO) are investigated as cathode electrocatalysts for hydrogen evolution reaction (HER) in alkaline water electrolysis. TEM, HR-TEM, XRD and ICP-MS are used to carry out the structural and morphological characterisation of the as-prepared rGO-AuPd and rGO-FePd nanocomposites and their electrocatalytic activity and stability is studied by voltammetry and chronoamperometry measurements. rGO-AuPd and rGO-FePd show HER onset overpotentials of 80 and 140 mV, respectively. A Tafel slope of 149 mV dec −1 is evaluated for rGO-AuPd at 25 °C, while rGO-FePd has worse performance. It is shown that rGO-AuPd nanocomposites are good candidates for application as novel electrocatalysts for the HER in alkaline media. [ABSTRACT FROM AUTHOR]

A child born from an Onchocerca volvulus infected mother is at increased risk of developing a high microfilarial load. High microfilarial loads are associated with a higher risk of developing onchocerciasis-associated epilepsy (OAE). Onchocerciasis is targeted for elimination through mass drug administration with ivermectin, which excludes pregnant women because of the potential teratogenic effect of ivermectin. Therefore, many pregnant women are O. volvulus infected during pregnancy in onchocerciasis-endemic areas. The consequence of such an infection on the risk of their children developing epilepsy has never been investigated. A case-control study was conducted in eight rural villages in Mahenge, Tanzania, an onchocerciasis endemic area with a high prevalence of epilepsy. Participants were enrolled in September 2021 and March 2022. Cases were persons with epilepsy, with a mean age of 26.3 (SD 9.0) years. Of these, 48.6% reported a history of nodding seizures. Controls were age-matched healthy individuals. Available mothers of participants were examined for palpable onchocerciasis nodules and tested with Ov16 ELISA. Seventy mothers of epilepsy cases and 49 of controls agreed to participate. Of these, 30 (42.8%) of mothers of cases and 19 (38.7%) of mothers of controls had palpable nodules (p-value = 0.80); 83.7%, 14.3% and 2% had one, two or three nodules, respectively. Ov16 positivity of the mothers of cases was 72.0% and of controls 75.8%. Using a logistic regression controlled for village and mothers' age, mothers of persons with epilepsy were more likely to present palpable nodules (OR = 2.65, 95% CI 1.06-7.11). Persons with OAE generally live in households close to blackfly breeding sites. Their mothers are likely to have similar high exposures to blackflies, explaining the high prevalence of nodules. Whether an O. volvulus infection in pregnant women may lead to an increased risk of OAE needs further investigation. [ABSTRACT FROM AUTHOR]

Background Cassia angustifolia, or senna, is a plant belonging to the Fabaceae family, widely used as a laxative and as a colouring agent in hair dyes. Senna is rarely reported as an occupational allergic sensitizer in the current literature. Aims To describe the case and diagnostic approach of a suspected occupational senna allergy. Case report A male phytopharmaceutical warehouse worker reported bronchial, conjunctival and nasal symptoms immediately upon exposure to senna. We were able to document in vitro sensitization, finding IgE-binding proteins in senna, and in vivo sensitization through positive skin tests and conjunctival provocation test. Conclusion Our study confirms that senna may cause occupational rhinoconjunctivitis symptoms with an IgE-dependent mechanism and is the first to confirm it through specific conjunctival provocation test. [ABSTRACT FROM AUTHOR]

Investigates the effect of noble gas irradiation on Fe-Ni multilayers with a very thin modulation and nominal composition in the Invar region Fe0.63Ni0.37. Evaluation of the formation/stability of the Fe-Ni phases formed under irradiation with different ions and doses; Magnetic hysteresis curves obtained.

Discusses a study which examined the iron-nitrogen phase transformations produced by the simultaneous use of temperature and ion bombardment. Principle behind nitrogen implantation; Description of the experimental setup; Findings.

Presents information on a study which determined the depth distribution of ion-implanted [sup10]boron in AZ111 photoresist in the 30-150 kiloelectrovolts energy range. Aspects of ion-implanted and irradiated polymers; Experimental procedure; Results and discussion; Conclusions.

Neuroplasticity - the capacity of the brain to change as a response to internal and external pressures - has been studied from a number of different perspectives. Perhaps one of the most powerful models is the study of populations that have been congenitally deprived of a sense. It has been shown that the right Auditory Cortex ( AC) of congenitally deaf humans is neuroplastically modified in order to represent visual properties of a stimulus. One unresolved question is how this visual information is routed to the AC of congenitally deaf individuals. Here, we performed volumetric analysis of subcortical auditory and visual brains regions - namely the thalamus (along with three thalamic nuclei: the pulvinar, the lateral geniculate nucleus and the medial geniculate nucleus), and the inferior and superior colliculi - in deaf and hearing participants in order to identify which structures may be responsible for relaying visual information toward the altered AC. Because there is a hemispheric asymmetry in the neuroplastic changes observed in the AC of the congenitally deaf, we reasoned that subcortical structures that also showed a similar asymmetry in their total volume could have been enlisted in the effort of relaying visual information to the neuroplastically altered right AC. We show that for deaf, but not for hearing individuals, the right thalamus, right lateral geniculate nucleus and right inferior colliculus are larger than their left counterparts. These results suggest that these subcortical structures may be responsible for rerouting visual information to the AC in congenital deafness. [ABSTRACT FROM AUTHOR]

The copper complexes has been synthesized resulting in a yield of 90%. The melting point of the complex and UV-Vis spectroscopy suggested complexation with high purity. The atomic absorption spectroscopy flame determined, together with the gravimetric analysis, the stoichiometric ratio obtained between metal and ligand for the complex. The potentiometric titration proposed which active sites are related to coordination with the metal, such coordination's sites were confirmed by infrared spectroscopy. Studies about the adsorption of chemical modifiers in the glassy carbon of the electrode surface resulting in obtaining ideal conditions for the electrode modification estimating the exact time of contact with modifier sunder ultrasound in different means of dissolution. The electrochemical properties of the electrodes howed improvements in electrochemical response to the redox couple Fe3-/4- than the unmodified electrode through organic dissolution. [ABSTRACT FROM AUTHOR]

The kinetics of starch digestion in the small intestine, nutrient utilisation and the performance of growing pigs that were fed diets containing maize of different particle sizes were evaluated. For the performance evaluation, 42 barrows and females (initial weight: 30.5 ± 1.78 kg) were used in a randomised block design with three treatments [maize with different geometric mean diameters (GMD) of 550, 700 and 850 μm] and seven replications. To evaluate the kinetics of starch digestion, one animal from each experimental trial was sacrificed. The small intestine was removed and separated into five equal parts. The starch digestibility in each segment was determined. To determine the total digestibility and nitrogen balance, 24 barrows (initial weight: 41.3 ± 4.72 kg) were housed in metabolism cages in a randomised block design with three treatments and eight repetitions. The animals that were fed diets containing maize of 550-μm GMD exhibited better (P = 0.008) feed conversion. However, the digestion of starch was gradual and variable among the degrees of grinding that were tested. There were higher (P = 0.008; 0.005 and 0.009) digestible energy, dry matter digestibility and nitrogen uptake in diets containing the maize ground to 550 and 700 μm in GMD. Thus, the smallest GMD of maize (550 μm) that was used in diets for growing pigs improves feed conversion. GMD of 550, 700 and 850 μm of maize were associated with rapid, intermediate and slow starch digestion, respectively. The digestion rate of starch in the small intestine of pigs can affect the efficiency of nutrient utilisation. This study aimed to evaluate the digestion kinetics of starch, nutrient utilisation and performance of growing pigs fed diets containing corn of different sizes. The smaller corn particle had higher rate of digestion and feed efficiency without impacting the digestibility of starch. This may influence the amino acid requirement of pigs and should be considered in the formulation of diets. [ABSTRACT FROM AUTHOR]

Increased expression and activity of inducible nitric oxide synthase (iNOS) may contribute to the pathogenesis of pre-eclampsia (PE) and gestational hypertension (GH). However, no previous study has examined whether genetic polymorphisms in the iNOS gene are associated with PE or GH. We examined whether two functional, clinically relevant iNOS genetic polymorphisms (the C−1026A polymorphism, rs2779249, in the promoter region, and the G2087A polymorphism, rs2297518, in exon 16) are associated with GH or with PE. We studied 565 pregnant women: 212 healthy pregnant (HP), 166 pregnant with GH and 187 pregnant with PE. Genotypes were determined by real-time PCR, using the Taqman allele discrimination assay. The PHASE 2.1 program was used to estimate haplotype distributions in the three study groups. We found no significant association between the C−1026A polymorphism and PE or GH (P>0.05). However, we found the GA genotype and the A allele for the G2087A polymorphism at higher frequency in PE, but not in GH, compared with HP (P<0.05). The haplotype analysis showed no significant intergroup differences (P>0.05). These findings suggest that iNOS genetic variants may affect the susceptibility to PE, but not to GH. [ABSTRACT FROM AUTHOR]

Synopsis Xylitol is a natural sugar derived from plants, fruits and vegetables, whose antimicrobial properties are described in the literature. This study aimed to evaluate the antimicrobial effectiveness of C-8 xylitol monoester, for its use as a preservative in cosmetic formulations. The minimum inhibitory concentration (MIC) was determined by the broth macrodilution method, and the antimicrobial effectiveness of C-8 xylitol monoester was determined by using challenge test method. The results obtained in the determination of minimum inhibitory concentration are between 1.0% and 1.25% for Staphylococcus aureus, Escherichia coli and Candida albicans and between 1.0% and 1.5% for Pseudomonas aeruginosa and Aspergillus niger. The amount of 1% of C-8 xylitol monoester was added to the lotion used in the challenge test, observing a rapid decline in the number of CFU g−1 in stages of evaluation after contamination of the product by all bacteria. The same occurs in relation to C. albicans, which shows a 90% reduction in the number of CFU g−1. Regarding A. niger, similar reduction is observed when pH value of the lotion is adjusted from 5.5 to 7.0. The results indicate that under the tests conditions, C-8 xylitol monoester has antimicrobial activity and could be considered as an alternative preservative for cosmetic formulations. [ABSTRACT FROM AUTHOR]

The paper by Yu and Saupe on the first biaxial nematic phase created excitement for a number of reasons. Some theories of biaxial phases already existed, but experimental observation was still lacking. The phase was discovered in a lyotropic system with three components, which in theory is difficult. Lyotropic liquid crystals are composed of supramolecular assemblies of amphiphilic molecules, which may change shape and size as a function of concentration and temperature. The experimental phase diagram of the lyotropic biaxial phase was rather complex, with the biaxial region inserted between nematic cylindrical and nematic discotic phases via second-order transitions. In addition, re-entrant behaviour was evident. Saupe investigated further systems experimentally, observing that the biaxial phase might be absent in cases where a direct transition between the cylindrical and discotic phases occurred. He provided a range of theoretical and experimental contributions on the properties of these lyotropics, but was very cautious regarding the detailed amphiphilic assemblies involved. The present paper reviews this area, focusing on proposals for the structure of the micellar assemblies. Emphasis is placed on recent papers which indicate a transformation of the two uniaxial shapes, in mixing conditions, both from the theoretical and the experimental point of view, and to questions still requiring further study. [ABSTRACT FROM AUTHOR]

Abstract: In the present work we have studied the photoluminescence (PL) behavior from Si nanocrystals (NCs) as a function of the excitation power density and annealing time. The NCs were produced in a SiO2 matrix by Si implantations from room temperature (RT) up to 700°C, followed by post-annealing in N2 atmosphere at high temperature. With this aim we have changed the excitation power density (from 2×10−3 W/cm2 up to 15W/cm2) and the annealing time (from 10min up to 15h). The strong PL signal, which at 15W/cm2 is composed by a single-peak structure (650–1000nm) centered at around 780nm, expands up to 1200nm showing a two-peak structure when measured at 20×10−3 W/cm2. The peak structure located at the short wavelength side is kept at ∼780nm, while the second peak, starting at around 900nm, redshifts and increases its intensity with the implantation temperature and annealing time. The effect of the annealing time on the PL spectra behavior measured at low excitation power agrees by the first time with the Si NC growth according to quantum confinement effects. [Copyright &y& Elsevier]

Abstract: In this work we present a photoluminescence (PL) study on Si nanocrystals produced by ion implantation on SiO2 targets at temperatures ranging between 25 and 800°C and subsequently annealed in N2 atmosphere. The PL measurements were performed at low excitation power (20mW/cm2) in order to avoid nonlinear effects. Broad PL spectra were obtained (from 650 up to 1050nm), presenting a line shape structure that can be reproduced by two superimposed peaks at around 780 and 950nm. We have observed that both PL intensity and line shape change by varying the annealing as well as the implantation temperatures. Implantations performed at 400°C or higher produce a remarkable effect in the PL line shape, evidenced by a strong redshift, and a striking intensity increase of the peak located at the long wavelength side of the PL spectrum. [Copyright &y& Elsevier]

Recently, we have presented the first exhaustive analysis of the world-wide airport network. Two important results of that study are that: (i) the world-wide airport network is a small-world network with power-law decaying degree and betweenness centrality distributions; (ii) the most connected cities (largest degree) are typically not the most central cities (largest betweenness centrality). This second finding is particularly significant because of results demonstrating that nodes with high betweenness tend to play a more important role in keeping networks connected than those with high degree. Here, we investigate if current network models can explain this finding and we show that they cannot. Thus, we propose a new model that explains this behavior in terms of the geo-political constraints that affect the growth of the airport network. We further hypothesize that in other infrastructures, affected by similar geo-political constraints, critical locations might not coincide with highly-connected hubs. [ABSTRACT FROM AUTHOR]

We briefly describe the toolkit used for studying complex systems: nonlinear dynamics, statistical physics, and network theory. We place particular emphasis on network theory--the topic of this special issue--and its importance in augmenting the framework for the quantitative study of complex systems. In order to illustrate the main issues, we briefly review several areas where network theory has led to significant developments in our understanding of complex systems. Specifically, we discuss changes, arising from network theory, in our understanding of (i) the Internet and other communication networks, (ii) the structure of natural ecosystems, (iii) the spread of diseases and information, (iv) the structure of cellular signalling networks, and (v) infrastructure robustness. Finally, we discuss how complexity requires both new tools and an augmentation of the conceptual framework--including an expanded definition of what is meant by a “quantitative prediction.” [ABSTRACT FROM AUTHOR]

We report on the diffusion of Bi, Er and Eu in the photoresist S1813. The implantation of Bi into the resist at low energies (E=20 keV) and fluences (Φ=1012 cm−2) allowed us to minimize both radiation damage and cluster formation. The impurity redistribution in the samples annealed between 100 and 300 °C was determined using the Rutherford backscattering technique. The results for Bi indicate regular thermal diffusion with an activation energy of Ea=680 meV. At higher fluences, the trapping in radiation-induced defects influence the migration behavior. However, the activation energy is hardly influenced (650 meV for implanted Bi at 5 × 1012 cm−2). Both the lanthanides Er and Eu implanted into the resist at fluences of 5 × 1012 and 1013 at/cm2 show quite a similar behavior as Bi implanted at the highest fluence with similar values for the activation energy (Ea(Eu)=525 meV and Ea(Er)=530 meV). [Copyright &y& Elsevier]

Ion-beam-assisted phase transformation in the Fe-N system has been studied in Fe samples implanted with N. By bombarding with Ar ions at temperatures in the 140oC < T < 420oC range, the epsilon-Fe2N -> epsilon-Fe2+xN + epsilon-Fe3.2N and epsilon-Fe3.2N + gamma-Fe4N phase transformations were induced. The ion-assisted phase transformations were studied as a function of firstly the temperature of the substrate, secondly the initial N concentration and thirdly the irradiation time. The results of the experiments show that the concomitant use of ion bombardment and temperature induces a given phase transformation at a temperature that is typically 40-50oC lower than that required for thermal annealing alone. [ABSTRACT FROM AUTHOR]

In this opening introductory paper, we discuss the possibility that scaleinvariant correlations may be a feature of biological and possibly even social systems. We illustrate this possibility by reviewing recent work at Boston University. Specifically, we focus first on the apparent scale-invariant correlations in non-coding deoxyribonucleic acid (DNA) and show that this feature can be used to distinguish coding and non-coding DNA. We argue that the inflating a degassed lung is characterized by a cascade of avalanches, as the airways successively open, and that distribution functions characterizing this cascade are scale invariant. Moving from the lung to the heart, we find that the sequence of interbeat intervals is characterized by scale-invariant correlations in health, but not in disease. Moving from individual organs to entire organisms, we discuss recent experimental evidence that the foraging behaviour of the wandering albatross is governed by a scale-invariant Levy distribution. Finally, we enquire whether scale invariance describes not only animal behaviour but also human behaviour. To this end, we analyse data on urban growth patterns, on finance and on economics. For all cases, we find empirical evidence of scaling behaviour. We conclude by asking why such complex systems might display scale invariance. [ABSTRACT FROM AUTHOR]

Abstract: Nanocavities and interstitial-type defects formed by neon plasma based ion implantation (PBII) in Si followed by annealing at 900°C have been studied in comparison with conventional ion implantation. Implantations were performed at 250°C and high fluence of ≈5×1016 cm−2. Using PBII, a rather uniform layer of cavities is observed from the surface. However, the mean diameter of cavities is smaller due to the interaction with the interstitial-type defects. In contrast with conventional implantation, these latter are created all over the cavity band because of the ion energy distribution that is characteristic of plasma based ion implantation. [Copyright &y& Elsevier]

• Quasi-static delamination growth is scrutinized with physics-based principles. • SED approach is augmented to explain the physics of mixed mode delamination growth. • A physics-based relation between crack growth at different mode mixities is proposed. • Data from the literature is used to evaluate the critical SED approach. • Mixed mode I/II fracture data is obtained from mode I data and material properties. This paper demonstrates how the critical strain energy density in the delamination tip vicinity may be used to explain the physics of delamination growth under mixed mode I/II. A theory previously proposed to physically relate mode I and mode II delamination growth is further extended towards describing the onset of mixed mode I/II delamination. Subsequently, data from the literature is used to demonstrate that this new concept of the critical strain energy density approach indeed explains, based on the physics of the problem, the strain energy release rate level at which crack onset occurs. This critical strain energy density for the onset of delamination appears to be independent of the opening mode. This means that, in order to characterize the fracture behaviour of a laminate, fracture tests at only one loading mode are necessary. Because the load level at which the physical delamination onset occurs at the microscopic level is much lower than the traditional engineering definition of macroscopic onset, further work must reveal the relationship between the macroscopically visible delamination onset, and the microscopic onset. [ABSTRACT FROM AUTHOR]

Damage accumulation in neon-implanted silicon with fluences ranging from 5×1014 to 5×1016 Ne cm-2 has been studied in detail. As-implanted and annealed samples were investigated by Rutherford backscattering spectrometry under channeling conditions and by transmission electron microscopy in order to quantify and characterize the lattice damage. Wavelength dispersive spectrometry was used to obtain the relative neon content stored in the matrix. Implantation at room temperature leads to the amorphization of the silicon while a high density of nanosized bubbles is observed all along the ion distribution, forming a uniform and continuous layer for implantation temperatures higher than 250 °C. Clusters of interstitial defects are also present in the deeper part of the layer corresponding to the end of range of ions. After annealing, the samples implanted at temperatures below 250 °C present a polycrystalline structure with blisters at the surface while in the other samples coarsening of bubbles occurs and nanocavities are formed together with extended defects identified as {311} defects. The results are discussed in comparison to the case of helium-implanted silicon and in the light of radiation-enhanced diffusion. [ABSTRACT FROM AUTHOR]

The structural evolution of Fe30Co70/Cu multilayers under ion irradiation is investigated in detail using x-ray techniques. The samples were irradiated with two different ions, 50 keV of He+ and 600 keV of Kr+, at room temperature. No substantial changes were observed after He+ irradiation; the He+ ions promote some disorder in the FeCo layers, an increase of the Cu(111) texture, and grain size. After Kr+ irradiation a structural phase transition from bcc to fcc occurs in the FeCo layers. A very pronounced increase of the Cu(111) texture and grain size is also observed. According to the equilibrium phase diagrams such fcc phase is not expected for the FeCo alloy at the composition of Fe30Co70. This fcc phase is imposed by the Cu fcc structure of the adjacent layers, which induce the regrowth of the FeCo layers structure from bcc to fcc during the relaxation period of the atomic collision cascades. Also, after the Kr+ irradiation a multilayer structure still persists, as showed by the x-ray reflectivity. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to synthesize the existing evidence on biomarkers related to coronavirus disease 2019 (COVID-19) patients who presented neurological events. Methods: A systematic review of observational studies (any design) following PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines and the Cochrane Collaboration recommendations was performed (PROSPERO: CRD42021266995). Searches were conducted in PubMed and Scopus (updated April 2023). The methodological quality of nonrandomized studies was assessed using the Newcastle‒Ottawa Scale (NOS). An evidence gap map was built considering the reported biomarkers and NOS results. Results: Nine specific markers of glial activation and neuronal injury were mapped from 35 studies published between 2020 and 2023. A total of 2,237 adult patients were evaluated in the included studies, especially during the acute phase of COVID-19. Neurofilament light chain (NfL) and glial fibrillary acidic protein (GFAP) biomarkers were the most frequently assessed (n = 27 studies, 77%, and n = 14 studies, 40%, respectively). Although these biomarkers were found to be correlated with disease severity and worse outcomes in the acute phase in several studies (p < 0.05), they were not necessarily associated with neurological events. Overall, 12 studies (34%) were judged as having low methodological quality, 9 (26%) had moderate quality, and 9 (26%) had high quality. Conclusions: Different neurological biomarkers in neurosymptomatic COVID-19 patients were identified in observational studies. Although the evidence is still scarce and conflicting for some biomarkers, well-designed longitudinal studies should further explore the pathophysiological role of NfL, GFAP, and tau protein and their potential use for COVID-19 diagnosis and management. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented in response to the article "Matrix Metalloproteinases (MMPs) and Tissue Inhibitors of MMPs Genetic Polymorphisms and Plasma Levels in Hypertensive Disorders of Pregnancy," by Karthikeyan and colleagues in the September 13, 2012 issue.

Presents a study which characterized multilayers of Fe[sub0.33]Zr[sub0.67] prepared by electron beam evaporation using conversion electron Mössbauer spectroscopy, Rutherford backscattering spectroscopy and x-ray diffraction. Result of the Rutherford backscattering spectrum of the as-deposited sample; Details on the x-ray diffractogram of the as-deposited samples.

An approach to control the interpore distances and nanopore diameters of 150-nm-thick thin aluminum films is reported here. The Al thin films were grown by sputtering on p-type silicon substrate and anodized with a conventional anodization process in a phosphoric acid solution. It was found that interpore distance and pore diameter are related to the aluminum grain size and can be controlled by annealing. The grain contours limit the sizes of alumina cells. This mechanism is valid for grain sizes supporting only one alumina cell and consequently only one pore. [ABSTRACT FROM AUTHOR]

In this work we explore the capabilities of the GUPIXWIN software to introduce a simple and straightforward way to obtain the efficiency of X-ray detectors commonly used in PIXE (Particle-Induced X-ray Emission) experiments. To that end, all geometrical parameters of the experimental setup including details of the detector used to detect X-rays must be well known in order to calculate the solid angle subtended by the detector’s crystal. The solid angle is calculated through a Monte Carlo program developed by Taylor and co-workers which is included in the GUPIXWIN software package. The H values are obtained from a set of experiments using standards. The results for the intrinsic efficiency of a Si(Li) detector are in good agreement with those obtained from Monte Carlo calculations and are compatible with a simple exponential law. [ABSTRACT FROM AUTHOR]

Despite 25 years of annual CDTI in Mahenge, Tanzania, the prevalence of onchocerciasis and epilepsy remained high in certain rural villages. In Uganda, bi-annual ivermectin distribution and larviciding rivers prevented new cases of onchocerciasis-associated epilepsy (OAE), including nodding syndrome (NS). In 2019, the Tanzanian government implemented a bi-annual CDTI programme in Mahenge. Additionally, we introduced a community-based awareness programme on epilepsy and onchocerciasis in four rural villages with high epilepsy and onchocerciasis prevalence (Mdindo, Msogezi, Mzelezi and Sali). We evaluated the impact of bi-annual CDTI and this community-based awareness programme on the incidence of epilepsy in these villages. We conducted pre- and post-intervention epilepsy surveys in 2017/2018 and 2021/2022, respectively. Each survey included door-to-door visits to screen all household members for suspected cases of epilepsy using a validated questionnaire and the examination of the suspected cases by a trained medical doctor to confirm the diagnosis. The annual incidence of epilepsy was presented as the number of new epilepsy cases per 100,000 persons-years and was calculated as the number of individuals who developed their first seizures during the five years before the survey divided by five times the total population included in the survey. In 2017/2018, 182 of the 5,444 (3.3%) surveyed individuals were confirmed to have epilepsy; 77.9% met the criteria of OAE, and 12.7% reported a history of nodding seizures. The incidence of epilepsy declined from 123 (95%CI: 88.2-173.9) in 2017/2018 to 34.1 (95%CI: 17.9-64.8) in 2021/2022, while that of NS declined from 26.3 (95%CI: 12.7-54.2) to 11.4 (95%CI: 3.9-33.4) in the same period. Bi-annual CDTI and a community-based awareness programme decreased the incidence of OAE in the rural study villages. This programme should be scaled up in Mahenge to prevent children from developing OAE in other rural villages with high epilepsy incidence. [ABSTRACT FROM AUTHOR]