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In the present work the synthesis and characterization of BaTi(O 1 - x S x ) 3 chalcogenide system is presented. The sample was synthesized by annealing in a tubular quartz furnace through high-temperature sulfurization processes, using powdered barium titanate as the precursor and under a reactive atmosphere CS 2 . After the synthesis process, the elemental composition of the obtained samples was determined by energy-dispersed X-ray fluorescence, finding a maximum concentration of 23.9% sulfur. XRD obtained the crystalline characteristics of the samples. The samples are crystalline with a hexagonal perovskite structure. Finally, using diffuse reflectance UV–Vis spectroscopy in the range of 200–800 nm, samples exhibiting more than 20% of sulfur showed a very low reflectance (<0.04), which leads to a high absorption coefficient that exceeds 10 5 cm - 1 in the ultraviolet region. And it is greater than 10 4 cm - 1 , for the rest of the measured spectral range. Furthermore, using the Tauc procedure, it was possible to determine the bandgap for the samples. BaTi( O 1 - x S x ) 3 has a direct bandgap and the value is gradually reduced to lower energies as a function of sulfur concentration. [ABSTRACT FROM AUTHOR]

In recent days, we live the mobile health revolution as medical apps are flourishing in the marketplace for all the different mobile devices. Diabetes apps are the most prevalent chronic disease-specific apps available commercially for Android or iOS. This study presents a selection through a holistic evaluation of some mobile apps for preventing or managing diabetes. After the selection, the study presents an evaluation from two perspectives: 1) mapping the implemented persuasion strategies in the mobile apps and 2) a usability evaluation with real users. This paper presents an evaluation of six mobile apps (Diabetes Prevent, my Sugar, Intellin Diabetes, Social Diabetes, Glucose Buddy, and One-Touch Reveal) for diabetes management or prevention. The results reveal that most of the apps are focus on controlling the disease. They had an accepted SUS score. However, they are not implementing the persuasion strategies as it should be done for medical systems. These findings suggested that it is essential to develop mobile applications based on international regulations towards covering aspects such as diagnosis, prevention, monitoring, treatment, and alleviation of disease. Furthermore, the applications should include persuasion strategies and integrating usability guidelines to change user's attitudes and behaviors and improve user satisfaction in mobile apps. [ABSTRACT FROM AUTHOR]

The combination of sedimentation, electrocoagulation (EC) and ozonation processes was investigated to treat wastewater from a medium-density fiberboard panel industry. The set-up of the EC process was composed of aluminum anodes and iron cathodes. For the sedimentation, the residence time was studied in a range from 5 to 120 min, achieving 80% suspended solids removal at 60 min. Three current densities have been investigated for EC: 57.1, 128.6 and 214.3 A/m2. The addition of 20 mL/min of polyamide (100 mg/L) was also tested using 200 mL/min of wastewater at an initial pH of 7.5 in order to analyze its effect on the pollutant removal, and therefore, on EC performance. The best operating EC conditions were 214.3 A/m2 of current density by the addition of polyamide aqueous solution. After EC, chemical oxygen demand (COD), color and turbidity removals of 66.3%, 99.7% and 99.9%, respectively, were obtained. For the ozonation process, an ozone flow of 2.5 g/h was fed to the wastewater, at an initial pH of 7.4. The effect of various ozone doses on COD, color and turbidity removal has also been studied. The highest achieved removal rates were 38.0%, 10.5% and 0.3% for COD, color and turbidity, respectively, at 20 min ozonation time. For the overall treatment, the removal percentages of these parameters were 90.9%, 99.7% and 99.9%, respectively. Furthermore, the combined treatment increased the wastewater biodegradability by a factor of 4.5. Thus, the combined processes of sedimentation, EC and ozonation can be a suitable alternative to reduce contaminant load in effluents from wood industries, and therefore, to comply with the Ecuadorian regulations. [ABSTRACT FROM AUTHOR]

Purpose: Performing a systematic review and meta-analysis to assess the evidence of intra-arterial therapies in liver metastatic breast cancer (LMBC) patients. Methods: A systemic literature search was performed in PubMed, EMBASE, SCOPUS for studies regarding intra-arterial therapies in LMBC patients. Full text studies of LMBC patients (n ≥ 10) published between January 2010 and December 2020 were included when at least one outcome among response rate, adverse events or survival was available. Response rates were pooled using generalized linear mixed models. A weighted estimate of the population median overall survival (OS) was obtained under the assumption of exponentially distributed survival times. Results: A total of 26 studies (1266 patients) were included. Eleven articles reported on transarterial radioembolization (TARE), ten on transarterial chemoembolization (TACE) and four on chemo-infusion. One retrospective study compared TARE and TACE. Pooled response rates were 49% for TARE (95%CI 32–67%), 34% for TACE (95%CI 22–50%) and 19% for chemo-infusion (95%CI 14–25%). Pooled median survival was 9.2 months (range 6.1–35.4 months) for TARE, 17.8 months (range 4.6–47.0) for TACE and 7.9 months (range 7.0–14.2) for chemo-infusion. No comparison for OS was possible due to missing survival rates at specific time points (1 and 2 year OS) and the large heterogeneity. Conclusion: Although results have to be interpreted with caution due to the large heterogeneity, the superior response rate of TARE and TACE compared to chemo-infusion suggests first choice of TARE or TACE in chemorefractory LMBC patients. Chemo-infusion could be considered in LMBC patients not suitable for TARE or TACE. Level of Evidence: 3a- [ABSTRACT FROM AUTHOR]

Monocytes play a key role in pathophysiology of antiphospholipid syndrome (APS), nevertheless it is unclear if microRNA expression is associated with particular APS features. Identify whether miR-19b-3p and miR-20a-5p expression in monocytes are associated with hallmarks of the APS. Fifty-seven APS patients and 18 healthy controls were studied. Expression of miR-19b-3p and miR-20a-5p was measured in monocytes by RT-qPCR. Both miR-19b-3p (AUC = 0.835, 95% CI 0.733–0.938; P < 0.001) and miR-20a-5p (AUC = 0.857, 0.757–0.957; P < 0.001) discriminated APS patients from healthy individuals. A cut-off point of 1.98 for miR-19-3p and 2.18 for miR-20a-5p showed that APS patients with low microRNA expression had higher levels of IgM and IgG anticardiolipin antibodies than patients with high microRNA expression. In addition, APS patients with low microRNA expression had higher IgG anti-β2 glycoprotein I antibody levels than their counterparts with high microRNA expression. Finally, miR-19b-3p and miR-20a-5p expression levels were significantly higher in APS patients using oral anticoagulants. Monocyte expression of miR-19b-3p and miR-20a-5p is low in APS, and patients with the lowest microRNA expression presented the highest levels of antiphospholipid antibodies. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the hard tissue volumetric and soft tissue contour linear changes in implants with two different implant surface characteristics after a ligature-induced peri-implantitis. Material and methods: In eight beagle dogs, implants with the same size and diameter but distinct surface characteristics were placed in the healed mandibular sites. Test implants had an external monolayer of multi-phosphonate molecules (B+), while control implants were identical but without the phosphonate-rich surface. Once the implants were osseointegrated, oral hygiene was interrupted and peri-implantitis was induced by placing subgingival ligatures. After 16 weeks, the ligatures were removed and peri-implantitis progressed spontaneously. Bone to implant contact (BIC) and bone loss (BL) were assessed three-dimensionally with Micro-Ct (μCT). Dental casts were optically scanned and the obtained digitalized standard tessellation language (STL) images were used to assess the soft tissue vertical and horizontal contour linear changes. Results: Reduction of the three-dimensional BIC percentage during the induction and progression phases of the experimental peri-implantitis was similar for both the experimental and control implants, without statistically significant differences between them. Soft tissue analysis revealed for both implant groups an increase in horizontal dimension after the induction of peri-implantitis, followed by a decrease after the spontaneous progression period. In the vertical dimension, a soft tissue dehiscence was observed in both groups, being more pronounced at the buccal aspect. Conclusions: The added phosphonate-rich surface did not provide a more resistant environment against experimental peri-implantitis, when assessed by the changes in bone volume and soft tissue contours. Clinical relevance: Ligature-induced peri-implantitis is a validated model to study the tissue changes occurring during peri-implantitis. It was hypothesized that a stronger osseointegration mediated by the chemical bond of a phosphonate-rich implant surface would develop an environment more resistant to the inflammatory changes occurring after experimental peri-implantitis. These results, however, indicate that the hard and soft tissue destructive changes occurring at both the induction and progression phases of experimental peri-implantitis were not influenced by the quality of osseointegration. [ABSTRACT FROM AUTHOR]

Retinoblastoma represents 3% of cancers in children under fifteen years of age. The standard paediatric treatment for saving the affected eye is supraselective intra-arterial chemotherapy performed in interventional rooms. In order to address the radiation toxicity due to the angiography, the aim of this study was to determine the typical dose value corresponding to the procedure, estimate the paediatric patients' eye lens dose and study the relationship between dose indicators and dose to the lens. An automatic dose management software was installed in two interventional rooms to obtain the distribution of the dose indicators kerma-area product and reference-point air kerma, getting a typical value 16 Gy·cm2 and 130 mGy, respectively (n = 35). The eye lens dose estimates were obtained with photoluminescent dosimeters placed on the patient's eyelids. In the left eye, the entrance surface air kerma was 44.23 ± 2.66 mGy, and 12.72 ± 0.89 mGy in the right eye (n = 10). There was a positive correlation between dose to the lens per procedure and dose indicators, with R2 > 0.65 for both eyes. Based on this information, the threshold for the onset of radiation-induce cataracts (500 mGy) will be exceeded if the treatment is performed for more than 8 sessions. [ABSTRACT FROM AUTHOR]

One of the most suitable approaches for the production of inorganic nanotubes is by means of carbon nanotube (CNT) templates coated by atomic layer deposition (ALD). This approach is attractive because it has the potential of controlling the wall thickness down to the Angstroms level. However, it is a recognized fact that the chemistry of the substrate surface can delay the full coverage at the initial stages of the ALD coating process, mainly due to nucleation issues. This is an important issue that might restrict laying down homogeneous coatings within the ultrathin range, which is the foundation for producing self-supported inorganic nanotubes. Here, we explore the early stage of the TiO nucleation on CNT templates systematically functionalized with different chemical groups (COOH, OH) or N-doped. The effects of the functionalization on the nucleation process from tetrakis (dimethylamino) titanium and water were meticulously studied by means of transmission electron microscopy. Observations revealed grain-like growth of TiO over pristine, purified and -OH-functionalized CNTs. In contrast, COOH functionalization yielded good conformality, which was improved on N-doped CNTs. Results were confirmed by X-rays photoelectron spectroscopy analysis. We recommend either COOH or N-doped CNTs for the production of ultrathin TiO nanotubes. [ABSTRACT FROM AUTHOR]

Emerging evidence proposes a link between immune changes and pain, which is consistent with the inflammation theory and the increased incidence of neurodegenerative diseases. Flavonoids have long been used because of their anti-inflammatory potential activity and they are considered a promising alternative to alleviate neuropathic pain. The aim of this study was to investigate the antihyperalgesic effect of hesperidin and the presence of pro-inflammatory cytokines evaluated at peripheral and central levels in the chronic constriction injury as model of neuropathic pain in rats. Mechanical and thermal hyperalgesia were assessed in the aesthesiometer and plantar tests, respectively, as related to the presence of cytokines concentrations (TNF-α, IL-1β and IL-6) in sciatic nerve and segments of the spinal cord after 15 days chronic constriction injury model in rats receiving vehicle or hesperidin. Antihyperalgesic response of hesperidin (100 mg/kg) was associated to the presence of cytokines mainly at several sections of the spinal cord suggesting not only peripheral but also its involvement in central sensitization in the experimental neuropathic pain. [ABSTRACT FROM AUTHOR]

Rockfall is a phenomenon which, when uncontrolled, may cause extensive material damage and personal injury. One of the structures used to avoid accidents caused by debris flows or rockfalls is flexible barriers. The energy dissipating devices which absorb the energy generated by rock impact and reduce the mechanical stresses in the rest of the elements of the structure are an essential part of these kinds of structures. This document proposes an overview of the performance of energy dissipating devices, as well as of the role that they fulfil in the barrier. Furthermore, a compilation and a description of the dissipating elements found in the literature are proposed. Additionally, an analysis has been performed of the aspects taken into account in the design, such as experimental (quasi-static and dynamic) tests observing the variation of the behaviour curve depending on the test speed and numerical simulations by means of several finite element software packages. [ABSTRACT FROM AUTHOR]

Esophageal cancer (EC) is an aggressive tumor that represents the 6th most common cause of cancer death worldwide. The estimated incidence in Spain is 2090 cases/year. Two main pathological subtypes exist, squamous cell carcinoma and adenocarcinoma. The main differences between them are localization and underlying factors which are the principal cause of the recent incidence changes observed in west countries. Staging techniques and treatment options which combine surgery, chemotherapy and radiotherapy, reflected the high complexity of the EC management. An undeniably multidisciplinary approach is, therefore, required. In this guide, we review the status of current diagnosis and treatment, define evidence and propose recommendations. [ABSTRACT FROM AUTHOR]

Background: Malignant gastrointestinal obstruction is a secondary complication of cancers in an advanced state. Treatment has consisted of gastrojejunostomy. However, the endoscopic placement of metallic stents has provided positive results. This study aimed to compare the efficiency of both therapeutic options.Methods: A total of 41 patients with gastrointestinal obstruction caused by inoperable neoplasm were treated endoscopically with enteral stent (24 patients) or gastrojejunostomy (17 patients).Results: In the endoscopic group (EG) 24 patients (100%) achieved efficient gastric emptying, as compared with 82.3% in the surgical group (SG). The difference was not significant. The average time for initiating oral food tolerance was 2.4 days for the EG and 5 days for the SG (p < 0.001). The average inpatient time was 7.1 days for the EG and 11.5 days for the SG (p < 0.001). Mortality at 30 days was lower in the EG (16.6%) than in the SG (29.4%) (p < 0.05). The survival time was 20 weeks for the EG and 21.6 weeks for the SG. The difference was not significant. The rate of complications was 4% in the (EG) and 17.6% in the (SG), with the difference was not significant.Conclusion: Endoscopic treatment of malignant gastrointestinal obstruction provides an adequate palliation of the symptoms. It is less invasive, avoids the morbidity associated with open gastrojejunostomy, and achieves a faster start to oral food and a shorter hospital stay, leading to a higher quality of life. [ABSTRACT FROM AUTHOR]

We report on a Spanish family in which three members of different generations were diagnosed with hereditary spherocytosis (HS). Additionally, one of them II-I (44-years-old), presented iron overload with hepatic deposit and needed treatment with periodic phlebotomies. The rest of the family members presented normal analytical values in iron metabolism. To investigate the presence of H63D and C282Y mutations in the HFE gene, patient II-I was found to be compound heterozygous and was the only family member presenting HS and this genetic condition in HFE. We propose a synergistic effect of HS and mutations in HFE as the cause of the iron deposits. [ABSTRACT FROM AUTHOR]

A novel low voltage tunable linear transconductor is presented. The approach is based on quasi-floating gate transistors achieving higher transconductance and better dc common mode rejection than previous implementations. A dynamic biasing technique improves the sensibility of the linearity to process variations. Measurement results of the circuit, designed in a 0.5 μm CMOS process from 1.4 V power supply, confirm the advantages of the proposed approach with a very high speed operation of 50 MHz of gain-bandwidth product, a IM3 of −40 dB and a nominal power consumption of only 490 μW. [ABSTRACT FROM AUTHOR]

This study compared the clinical and radiographic outcome of three techniques of anterior fusion for cervical disc herniation: Cloward fusion with autograft, Cloward fusion with freeze-dried bone, and BAK-C device fusion. In a cohort of 84 consecutive patients, 34 were treated by classic autograft Cloward's technique, in 26 patients freeze-dried xenograft Surgibone was used and in the last 24 patients a BAK-C titanium device was implanted. The mean follow-up period of this last group was 14.6 months. All patients were operated by the same surgeon at the same hospital and all underwent single-level surgery. Results were evaluated on the basis of patient satisfaction and postoperative capacity to work. There was no significant difference between the three groups related to the preoperative assessment. The analysis revealed that BAK-C patients had significantly shorter hospital stays. No postoperative cervical collar was worn by BAK-C patients and they had the highest percentage of excellent clinical results. Concerning radiographic evaluation, BAK-C achieved a more stable fixation of the involved segment without complications in contrast with the two others, which presented a significant incidence of extrusion, collapse, kyphosis and pseudarthrosis. Measurement of the progressive kyphosis grade shows statistically significant differences between the three groups. BAK-C patients had the lowest kyphosis grade at the end of the follow-up. There is an important correlation between collapse, collapse with kyphosis and pseudarthrosis with bad clinical results. In conclusion, the BAK-C device showed significant advantages, including higher patient satisfaction, unnecessary postoperative collar, early rehabilitation and a lower rate of complications. Furthermore, BAK-C is cost effective because of it shortens postoperative hospital stay and allows an earlier return to work. [ABSTRACT FROM AUTHOR]

This paper studies goodness-of-fit tests for the bivariate Poisson distribution. Specifically, we propose and study several Cramér-von Mises type tests based on the empirical probability generating function. They are consistent against fixed alternatives for adequate choices of the weight function involved in their definition. They are also able to detect local alternatives converging to the null at a certain rate. The bootstrap can be used to consistently estimate the null distribution of the test statistics. A simulation study investigates the goodness of the bootstrap approximation and compares their powers for finite sample sizes. Extensions for testing goodness-of-fit for the multivariate Poisson distribution are also discussed. [ABSTRACT FROM AUTHOR]

The geometric and the electronic structures, the magnetic moments, and the magnetocrystalline anisotropy energy of bcc-Fe nanowires with z-axis along the (110) direction are calculated in the framework of ab initio theories. In particular, we report a systematic study of free standing nanowires with geometries and sizes ranging from diatomic to 1 nm wide with 31 atoms per unit cell. We found that for nanowires with less than 14 atoms per unit cell, the ground-state structure is body-centered tetragonal. We also calculated the contributions of the dipolar magnetic energy to the magnetic anisotropy energy and found that in some cases, this contribution overcomes the magnetocrystalline part, determining thereby the easy axis direction. These results emphasize the importance and competition between both contributions in low dimensional systems. [ABSTRACT FROM AUTHOR]

A novel automatic frequency tuning circuit for continuous-time filters is presented. Based on the switched-capacitor technique, the circuit offers an advantage in terms of simplicity resulting from the use of only two matched current sources, an operational amplifier with relaxed specifications and a transconductor that is a replica of the filter transconductors. Despite the simplicity of the scheme, the accuracy of the system is less than 1 % of frequency error. The circuit has been designed in a 0.5 μm CMOS technology with a 3.3 V power supply and simulation results confirm the suitability of the proposed approach. [ABSTRACT FROM AUTHOR]

A CMOS highly linear voltage-controlled transconductor suitable for Gm-C filter design is presented. The control loop to program the transconductance maintains the input transistors in triode region with a compact topology. Measurement results for the transconductor fabricated in a 0.5-μm CMOS technology feature a spurious-free dynamic range (SFDR) of 72 dB for 1 V differential inputs at 1 MHz. The voltage to current converter ensures a high linearity level for a wide transconductance range. Functionality of the transconductor is shown in a fifth-order Gm-C tunable complex filter well suited for a dual-mode Bluetooth/Zigbee transceiver. [ABSTRACT FROM AUTHOR]

Several long-term temporal analyses of the structure of Robertsonian (Rb) hybrid zones in the western house mouse, Mus musculus domesticus, have been performed. Nevertheless, the detection of gradual or very rapid variations in a zone may be overlooked when the time elapsed between periods of study is too long. The Barcelona chromosomal polymorphism zone of the house mouse covers about 5000, km2 around the city of Barcelona and is surrounded by 40 chromosome telocentric populations. Seven different metacentrics and mice with diploid numbers between 27 and 40 chromosomes and several fusions in heterozygous state (from one to seven) have been reported. We compare the present (period 2008-2010) and past (period 1996-2000) structure of this zone before examining its dynamics in more detail. Results indicate that there is not a Rb race in this area, which is consistent with the proposal that this zone was probably originated in situ, under a primary intergradation scenario. The lack of individuals with more than five metacentrics in heterozygous state in the current period suggests that selection acted against such mice. By contrast, this situation did not occur for mice with fewer than five fusions in heterozygous condition. Changes in human activity may affect the dynamics of gene flow between subpopulations, thus altering the chromosomal composition of certain sites. Although these local variations may have modified the clinal trend for certain metacentrics, the general staggered structure of the zone has not varied significantly in a decade. [ABSTRACT FROM AUTHOR]

Network operators are willing to provide a range of services in the hope of maximizing their profits: from the highly available connectivity services for key business customers to the unprotected or even best effort services for residential customers. These services are being provided through IP/multiprotocol label switching (MPLS) over wavelength-switched optical networks (WSON) networks. Such multilayer network enables the application of optimal load balancing between the packet and the optical layer, optimizing both the cost of the packet layer and the utilization of the WSON. To provide highly available services, redundant network resources need to be added to the network providing survivability against failures; generally speaking, the higher the survivability degree, the higher both the capital and the operational expenditures (CAPEX and OPEX, respectively) of the network. In this work, we design networks to meet specific availability objectives considering single failures in optical links, IP/MPLS nodes, and optoelectronic ports. The benefits of the designed networks are evaluated from an economic perspective defining costs and revenues models and using Net Present Value as a metric to evaluate future cash flows after an investment. To this end, CAPEX and OPEX, including power consumption and maintenance, and penalties as a consequence of service level agreement breaches are considered. Exhaustive numerical results on several reference network scenarios demonstrate how the value of the network can be maximized by tuning availability objectives. [ABSTRACT FROM AUTHOR]

The effects due to d-orbital polarization in collision processes between a single rhodium atom and a 12 atom rhodium cluster are investigated by means of ab initio molecular dynamics. For the initial configuration of the 12 atom rhodium targets we adopt two different low energy structures. The kinetic energy and impact parameter of the projectile are chosen in such a way that fusion, scattering and fragmentation of the cluster do occur. The collision is treated by means of density functional theory molecular dynamics (DFT-MD). Both spin unpolarized and polarized treatments are implemented in order to clearly distinguish the effects that are due to d-orbital polarization. We find a novel block dynamics, of parts of the cluster, which is due to the directional nature of d-bonds. In addition, the treatment of the collisions by means of high temperature DFT dynamics yields promising minimal energy configurations, which are target dependent but are difficult to obtain otherwise. [ABSTRACT FROM AUTHOR]

Study design:Pharmacologically blocking the spinal cord produces sedative effects and reduces anesthesia requirements in patients and animals. Whether spinal cord injury also reduces anesthesia requirements remains unclear.Methods:We retrospectively analyzed data from urethane-anesthetized rats15 to assess anesthesia requirements immediately after complete thoracic transection of the spinal cord. The depth of anesthesia was monitored up to 12 h after spinal transection by the reflexes to noxious stimuli and by electrophysiological recordings from the infragranular layers of the primary somatosensory cortex. Whenever animals displayed electrophysiological and/or behavioral signs of activation, we delivered an additional dose of anesthesia. Anesthetic requirements in animals receiving spinal transection (n=11) were compared with control animals receiving 'sham' lesion (n=9).Results:The cumulative dose necessary to maintain a stable level of anesthesia was significantly lower in transected animals compared with control animals. By about 7 h after spinal cord injury, on average the cumulative dose of urethane was only 1.13±0.14 of the original dose, compared with 1.64±0.19 of the original dose in control animals.Conclusions:Spinal transection immediately decreased anesthetic requirements in rats. To establish whether these results are relevant for patients with spinal cord injury will require further investigation. [ABSTRACT FROM AUTHOR]

Matching accuracy of capacitors at the first stage of the residue amplifier limits the overall resolution in pipelined analog-to-digital converters. A new residue amplifier is presented in this paper which is inherently insensitive not only to capacitor ratio but also to amplifier offset voltage and gain errors. Experimental and simulation results are provided to show how the proposed technique senses and compensates these errors. [ABSTRACT FROM AUTHOR]

Collision processes between a single gold atom and a gold cluster are investigated by means of ab initio techniques. The targets we consider are minimum energy 13 gold atom clusters. The kinetic energy of the projectile and its impact parameter are chosen within a range such that the three regimes we are mainly interested in studying (fusion, scattering and fragmentation) are realized. The results of the collision processes are treated using density functional theory molecular dynamics (DFT-MD), analyzed in detail, and compared with previous work, which was carried out using phenomenological potentials and classical molecular dynamics. The differences between classical MD and DFT-MD are quite significant. [ABSTRACT FROM AUTHOR]

This work presents the fabrication and characterisation of a versatile lab-on-a-chip system that combines magnetic capture and electrochemical detection. The system comprises a silicon chip featuring a series of microband electrodes, a PDMS gasket that incorporates the microfluidic channels, and a polycarbonate base where permanent magnets are hosted; these parts are designed to fit so that wire bonding and encapsulation are avoided. This system can perform bioassays over the surface of magnetic beads and uses only 50 μL of bead suspension per assay. Following detection, captured beads are released simply by sliding a thin iron plate between the magnets and the chip. Particles are captured upstream from the detector and we demonstrate how to take further advantage of the system fluidics to determine enzyme activities or concentrations, as flow velocity can be adjusted to the rate of the reactions under study. We used magnetic particles containing β-galactosidase and monitored the enzyme activity amperometrically by the oxidation of 4-aminophenol, enzymatically produced from 4-aminophenyl-β- d-galactopyranoside. The system is able to detect the presence of enzyme down to approximately 50 ng mL−1. [ABSTRACT FROM AUTHOR]

OBJECTIVE: We have carried out a bibliometric analysis of scientific publications related to attention-deficit hyperactivity disorder (ADHD) and its pharmacological treatment over the period 1980-2005. METHOD: We selected (in EMBASE and MEDLINE databases) documents that contained in their title the descriptors attention deficit hyperactivity disorder, attention deficit disorder, ADHD and ADD. As bibliometric indicators of production and dispersion we applied Price's Law and Bradford's Law, respectively. We also calculated the national participation index (PI) and correlated it with overall PI in biomedical and health sciences, with PI in the discipline of Psychiatry and with the social-health indicators (per capita Gross Domestic Product, number of physicians and total per capita expenditure on health). RESULTS: We obtained 5,269 original documents (2,325 corresponded to pharmacological therapy). Our results indicate fulfilment of Price's Law, since scientific production on ADHD undergoes exponential growth (correlation coefficient r = 0.9859, vs. r = 0.9011 after linear adjustment). The most widely studied drugs are methylphenidate (1,251 documents). Division into Bradford zones yields a nucleus occupied exclusively by the Journal of the American Academy of Child and Adolescent Psychiatry (500 articles). A total of 866 different journals were employed. Twelve of the first 20 used journals have an Impact Factor > 2. The principal producer country is the United States (PI = 44.2). Only four countries, of the 20 major producers in health sciences, surpass their own PI in the field of Psychiatry (Brazil, China, Spain and the United States). The correlation between PI and total number of physicians for each country situates Canada, Australia, the United States and Israel in the top positions. CONCLUSION: Productivity on ADHD has undergone exponential growth in the period 1980-2005, without evidence a saturation point. [ABSTRACT FROM AUTHOR]

The emerging role of glycans as versatile biochemical signals in diverse aspects of cellular sociology calls for establishment of sensitive methods to monitor carbohydrate recognition by receptors such as lectins. Most of these techniques involve the immobilization of one of the binding partners on a surface, e.g. atomic force microscopy, glycan array and Surface Plasmon Resonance (SPR), hereby simulating cell surface presentation. Here, we report the synthesis of fluorescent glycoconjugates, with a functionalization strategy which avoids the frequently occurring ring opening at the reducing end for further immobilization on a surface or derivatization with biotin. In order to improve the versatility of these derivatized glycans for biological studies, a new approach for the synthesis of biotinylated and fluorescent glycans has also been realized. Finally, to illustrate their usefulness the neoglycoconjugates were immobilized on different surfaces, and the interaction analysis with a model lectin, the toxin from mistletoe, proved them to act as potent ligands, underscoring the merit of the presented synthetic approach. [ABSTRACT FROM AUTHOR]

Presents a study on the influence of inflammatory nociception on the anxiolytic-like effect of diazepam and buspirone in rats. Study procedure; Several tests performed in the study; Study findings.

TheArabidopsis thalianaKAT1, an inward-rectifying potassium channel, shares molecular features with theShakerfamily of outward rectifier K+ channels. The KAT1 amino-acid sequence reveals the presence of a positively charged S4 and a segment containing the TXGYGD signature sequence in the pore (P) region. To test whether the inward-rectifying properties of KAT1 are due to reverse orientation in the membrane, such that the voltage sensor is oriented in the opposite direction of the electric field compared with theShakerK+ channel, we have inserted a flag epitope in the NH2 terminus or the S3-S4 loop. The KAT1 and tagged constructs expressed functional channels in whole cells,Xenopusoocytes and COS-7. The electrophysiological properties of both tagged constructs were similar to those of the wild type. Immunofluorescence with an antibody against the flag epitope and an anti-C terminal KAT1 determined the membrane localization of these epitopes and the orientation of the KAT1 channel in the membrane. Our data confirm that KAT1 in eukaryotic cells has an orientation similar to theShakerK+ channel. [ABSTRACT FROM AUTHOR]

The Arabidopsis thaliana KATI, an inward-rectifying potassium channel, shares molecular features with the Shaker family of outward rectifier K+ channels. The KATI amino-acid sequence reveals the presence of a positively charged S4 and a segment containing the TXGYGD signature sequence in the pore (P) region. To test whether the inward-rectifying properties of KATI are due to reverse orientation in the membrane, such that the voltage sensor is oriented in the opposite direction of the electric field compared with the Shaker K+ channel, we have inserted a flag epitope in the NH, terminus or the S3-S4 loop. The KATI and tagged constructs expressed functional channels in whole cells, Xenopus oocytes and COS-7. The electrophysiological properties of both tagged constructs were similar to those of the wild type. Immunofluorescence with an antibody against the flag epitope and an anti- C terminal KATI determined the membrane localization of these epitopes and the orientation of the KATI channel in the membrane. Our data confirm that KATI in eukaryotic cells has an orientation similar to the Shaker K+ channel. [ABSTRACT FROM AUTHOR]

Summary. Neprilysin has recently been reported to be the major physiological Aβ-degradating enzyme. In this study we describe a new biallelic polymorphism in the 3′UTR of the neprilysin gene in a representative population sample. The *159C/C genotype was found to be associated with an increased risk for Alzheimer's disease in an age-dependent manner. Adjusting for sex and APOE status, an odds ratio of 2.74 (p < 0.05) was observed among patients under 75 years old. [ABSTRACT FROM AUTHOR]

In the present work several known mammalian leukocyte functions such as directed mobility, proliferative response to mitogens, antibody-dependent cellular cytotoxicity (ADCC) and natural killer (NK)-mediated cytotoxicity were studied in female and male Mauremys caspica turtles. Since the reptilian thymus shows seasonal variations in its structure, we have performed all the assays along the seasonal cycle. Our results show that thymic cells from M. caspica are able to migrate through a chemo-attractant gradient, to proliferate in response to the mitogens phytohaemagglutinin (PHA) and concanavalin A (Con A), and to kill tumoral target cells by both ADCC-mediated and NK-mediated cytotoxicity. Those functions were differentially affected by the seasonal cycle; in general, in autumn the functions studied showed the smallest values for both sexes, while in summer the highest values of cytotoxicity and chemotaxis were found in females. The proliferative responses to PHA and Con A were higher for both sexes in spring and for females in winter than in the other seasons. In summary, thymic cells from M. caspica show a wide range of immune functions, and these are modulated heterogeneously by the seasonal cycle in both sexes. [ABSTRACT FROM AUTHOR]

Cites a study published in 'Agroforestry Systems,' where fine root biomass and fine root productivity were measured during one year in plantations of cocao planted in alluvial soil in Turrialba, Costa Rica. Variance in fine root biomass at the beginning of rainy season; Way to minimize nutrient competition between shade trees and cocao; Estimation of nutrient inputs in fine root turnover.

We conducted laboratory tests with six species of plants to determine their ability to remove benzene, trichloroethylene (TCE) and toluene from air. The objective of this proof-of-principal study was to evaluate the idea that phytoremediation techniques might be used to lower the concentrations of indoor air pollutants, such as volatile or semi-volatile organic compounds. Plants were exposed to the pollutants singly or in mixtures in an airtight chamber, and concentrations of the pollutants in the chamber were monitored through time to assess plant effects on the pollutants. In several experiments, we measured air temperature and CO2, as well. Lower surfaces of leaves of several of the species we tested were also examined by scanning electron microscopy to determine stomate abundance and size, and to provide information about leaf-surface elemental composition (by X-ray emission spectroscopy). Several of the species demonstrated an extensive ability to remove benzene from air. Gas chromatography methods allowed a reasonably direct, continuous monitoring of the kinetics and overall efficiency of the pollutant-removal process. We found that pollutant removal efficiency varied in response to plant species and the pollutant. Of the pollutants tested, benzene was most efficiently removed from air by Pelargonium domesticum, Ficus elastica and Chlorophytum comosum. Kalanchoe blossfeldiana, a common ornamental plant, appeared to take up benzene selectively over toluene, and TCE was removed efficiently from the air by C. comosum. Pentane, sometimes used as an internal standard in GC/MS, was removed from air by at least four of the species. For C. comosum, TCE appeared to lower the removal rates of benzene and pentane. Low-vacuum scanning electron microscopy provided information on stomate size and density and permitted rapid initial elemental analysis of the plant-leaf surface by X-ray emission spectroscopy. Our results indicate that simple tests for pollutant uptake, morphological and chemical features of plants, and plant detoxification enzyme activity might be used in multivariate fashion to identify plant species capable of removing volatile or semi-volatile pollutants from air. [ABSTRACT FROM AUTHOR]

The life expectancy of HIV-positive individuals has been prolonged in recent years, as a consequence of the wide use of antiretroviral drugs and primary prophylaxis for the most common opportunistic infections. In HIV-positive persons infected parenterally, chronic viral liver disease (CVLD), mainly that caused by hepatitis C virus (HCV), is frequently seen. Moreover, chronic hepatitis C seems to present a more accelerated course in HIV-infected patients, leading to cirrhosis and liver failure in a shorter period of time. The aim of the present study was to investigate the impact of CVLD on the morbidity and mortality of HIV-positive patients. A retrospective analysis of the causes of hospital admission during a 4.5-year period in a reference centre for AIDS situated in Madrid was performed. Decompensated liver disease (encephalopathy, ascites, jaundice), or complications directly related to it (gastrointestinal bleeding, hepatorenal syndrome, peritonitis) were diagnosed in 143 (8.6%) of 1670 hospital admissions. These episodes of CVLD corresponded to 105 different individuals, a quarter of whom had two or more re- admissions. HCV alone or in combination with other hepatotropic viruses was involved in 93 (88.6%) patients admitted for CVLD. Death directly associated with CVLD occurred in 15 individuals, which represented 4.8% of the total causes of inhospital mortality during the study period, and represented the fifth cause of death in hospital for HIV-infected patients. In conclusion, CVLD represents an important cause of hospital admission and death in HIV-infected drug users. [ABSTRACT FROM AUTHOR]

Stability of Schiff bases from Pyridoxal-5′-phosphate and α- and non α-amino acids and amines have been studied in a wide range of pH. Furthermore the transamination process for the PLP-serine Schiff base and the cyclization reaction of PLP-histidine Schiff base have also been studied. Results show that the α-position on carboxyl group of amino acids plays an important role on the mechanism of hydrolysis of imine bond. Absence of ionic groups in the surroundings of that bond seems to be an important fact of stability. In the transamination reaction, the rate-determining step is the isomerization of the Schiff base to ketoimine, since the rate constants for disappearance of Schiff base coincide with the rate constants for PMP formation. This process is catalyzed by the OH/HO system and the monoprotonated amino acid. [ABSTRACT FROM AUTHOR]

Surgical gastrojejunostomy is the standard treatment for malignant gastric outlet obstruction, although it is associated with significant morbidity and mortality. The aim of this study was to evaluate the efficacy and feasibility of a newly designed expandable metal stent (Wallstent Enteral) to treat malignant gastric outlet obstruction. Six patients (five women, one man; mean age 76 years) underwent stenting. Stents 20-22 mm in diameter and 60-90 mm in length were deployed through a duodenoscope channel under endoscopic and fluoroscopic control, without previous stricture dilation. In all six cases the stent was adequately positioned and food intake was possible in the next 24 h. The mean time for hospital discharge was 2.5 days (1-5 days), without complications related to the procedure. Five patients died in the follow-up from progression of their cancer and one remains alive; none had recurrent obstruction. The median survival time was 9 weeks (95% CI: 3-15 weeks). In conclusion, endoscopic self-expandable stent (Wallstent Enteral) placement is safe and effective palliation for malignant gastric outlet obstruction and appears to be a therapeutic alternative to surgical gastrojejunostomy. [ABSTRACT FROM AUTHOR]

Presents a letter to the editor about the diagnosis of aortoesophageal fistula.

In group A there was a fall in PVRI while SVRI was maintained stable, both of them were statistically significant (#). Urine output, FENa and FECl were slightly higher in group A, but none of these were statistically significant (*). [ABSTRACT FROM AUTHOR]