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En este trabajo se evaluó la electrocoagulación con electrodos de grafito como técnica avanzada para el tratamiento de agua residuales del proceso de depilado en curtiembres, con el objeto de reducir la turbiedad, carbono orgánico total y concentración de sulfuros en este tipo de efluentes. Las propiedades inertes del grafito ofrecen la ventaja de no generar la dilución de iones metálicos en el agua. En este sentido, se analizó el efecto del tiempo de reacción (30 min y 60 min), el número de electrodos de grafito (2 y 4) y la intensidad de corriente aplicada (12 A y 24 A) sobre el porcentaje de disminución o reducción de concentración de las variables mencionadas previamente. Para el desarrollo del proyecto se planteó un diseño experimental de tipo factorial 23. El volumen de agua para cada ensayo fue de 0.002 m3 y la temperatura del agua fue de 20 °C ± 2 °C. Las variables de respuesta para determinar la efectividad del proceso fueron el porcentaje de remoción de turbiedad, Carbono Orgánico Total y Demanda Química de Oxígeno. Los resultados experimentales fundamentados en el Análisis de Varianza permitieron establecer que los factores de proceso o variables experimentales seleccionadas influyen sobre los porcentajes de remoción de las variables de respuesta, además, se determinó que las condiciones de mayor remoción de sulfuros y turbiedad se lograron con 4 electrodos, 24 A y 60 minutos de tiempo de reacción, para esas condiciones la densidad de corriente aplicada fue de 107.14 A/m2. Los mayores porcentajes de remoción fueron 41.46 %, 75.02 % y 35.73 % para sulfuros, turbiedad y Carbono Orgánico Total respectivamente. Durante los ensayos no se observó desgaste en los electrodos y tampoco cambios de color en el agua.

Cancer immunotherapy holds great promise for the treatment of solid tumors, but its effectiveness is hindered by the recruitment of regulatory T cells (Tregs), which inhibit anti-tumor immune responses. We report here that cytosolic dsDNA, a characteristic of many cancer cells, upregulates expression of the Treg-recruitment chemokine CCL22 in multiple types of malignant epithelial cells. We also identified that interferon regulatory factor 3 (IRF3) is a key regulator of CCL22 in response to dsDNA. Both IRF3 and NF-κB are activated downstream of the stimulator of interferon genes (STING), a primary effector protein responding to multiple cytosolic dsDNA sensors. IRF3 activation by STING triggers robust expression of type I interferons, which can boost anti-tumor immune responses. Thus, STING agonists have been used clinically to activate IRF3 during immunotherapy. However, STING activation in some cases is reported to paradoxically foster a pro-tumor, immunosuppressive environment. Our finding that IRF3 regulates CCL22 in response to dsDNA suggests a possible mechanism contributing to STING-mediated immunosuppression. In addition, we found that cultured cancer cells appear able to evolve mechanisms to co-opt nucleic acid sensing pathways to upregulate CCL22, suggesting that these pathways may contribute to acquired immune evasion in tumors with increased cytosolic dsDNA.

With one in 59 children diagnosed with autism, higher education institutions are experiencing increasing enrollments of autistic students. Furthermore, autistic students are disproportionately more likely to identify as gay and lesbian in their sexual orientation and as transgender or genderqueer in their gender identity compared with nondisabled peers. This case study challenges readers to consider the role that educational leaders can play in addressing the complexities of supporting a student named Erik, a gay, autistic student who is considering “coming out.” Readers are also challenged to consider implications about addressing campus climate issues for students with multiple, intersecting identities.

Hip fracture are an important cause of morbidity and mortality in old patients. The one-year mortality after a hip fracture increase between 14 to 47%. The main objective was to analyze the risk factors associated with mortality after a hip fracture in a low-income population.Retrospective study of patients with traumatic hip fracture in a four-year period in an orthopedic training hospital. The data collected was age, gender, Charlson comorbidity index (CCI), delay time in days for surgery, duration in hours for surgical procedure, transfusion. Two groups were analyzed, alive patients and deceased patients.A total of 96 patients with traumatic hip fracture was analyzed. Mortality rate in the first year was pf 16.6%, and at the end of the follow-up was 32.2%. The alive patients showed better values of CCI with a value of 4.2 ± 1.1 versus 5.2 ± 1.0 in the deceased patients. When compared delay time for surgery and duration of surgical procedure did not observe significant difference between patients alive and deceased.The delay time of surgery did not affect the mortality after a traumatic hip fracture in old patients with economic low-income.Las fracturas de cadera representan una causa importante de morbimortalidad en los adultos mayores. La mortalidad a un año posterior a una fractura de cadera incrementa entre 14 y 47%. El objetivo de este estudio fue analizar los factores de riesgo que impactan la tasa de mortalidad posterior a una fractura de cadera en una población de bajos recursos.Se analizaron de manera retrospectiva pacientes con fractura de cadera traumática en un período de cuatro años en un hospital universitario con entrenamiento ortopédico. Los datos recolectados incluyeron edad, género, índice de comorbilidad de Charlson (CCI), tiempo en días para la cirugía y duración del procedimiento quirúrgico, así como necesidad de transfusión. Se analizaron dos grupos, pacientes vivos y pacientes fallecidos.Se evaluó un total de 96 adultos mayores con fractura de cadera. La tasa de mortalidad durante el primer año fue de 16.6%, mientras que al final del seguimiento fue de 32.2%. El grupo de sobrevivientes presentó una mejor evaluación de acuerdo con el CCI con valor de 4.2 ± 1.1 versus 5.2 ± 1.0 en los pacientes fallecidos. No se encontró diferencia estadísticamente significativa en la mortalidad entre ambos grupos al comparar los días de espera de tiempo quirúrgico y la duración de la cirugía.El retraso de la cirugía no afecta la tasa de mortalidad después de una fractura de cadera en pacientes de edad avanzada con bajo ingreso económico.

The use of high-quality seeds is essential for the crop to express its full potential. The application of seed treatment constitutes a widely spread operation, every year new products are discovered and used for seed treatment, which can provide a protective effect against pests that attack the seeds, as well as physiological effects to favor the growth and initial development of plants, however, little is known about the influence of insecticides on seed germination and the emergence of soybean seedlings. The experiment was carried out in the Seed Quality Analysis Laboratory and in the experimental field of the Agrarian Sciences Faculty of the National University of Asunción-Paraguay. The objective consisted of evaluating the efficacy of chemical insecticides applied to soybean seeds to control lepidopteran caterpillars during the implantation of the crop, and the effect on the germination of seeds in the laboratory and the emergence in the field. Commercial soybean seeds were used and the treatments were the following (in cc of c.p./100 kg seeds): control (without treatment), thiamethoxam (200), cyantraniliprole + thiamethoxam (200), thiamethoxam + lambda-cyhalothrin (200), imidacloprid (400), imidacloprid + thiodicarb (500) and fipronil (200). The variables evaluated were: germination under laboratory conditions, number of larvae presented at 14, 21 and 28 days after emergence, seedling emergence and efficacy of chemical products in the field. The design used in the field was complete block to the random and in laboratory fully randomized, with seven treatments and 4 replications with a total of 28 experimental units for both trials. The data obtained were compared through the analysis of variance using the statistical software SASM-Agri and those variables that presented significant statistical differences between the means of the treatments were compared using the Scott-Knott test at 5% probability, while efficacy was determined by the Abbot formula. The data show that the chemical insecticides did not affect the germination of seeds in the doses tested. The highest percentages of emergence in the field were obtained with the insecticides thiamethoxam, cyantraniliprole + thiamethoxam, imidacloprid and imidacloprid + thiodicarb. At 28 day after seedling emergence the active ingredients cyantraniliprole + thiamethoxam and imidacloprid + thiodicarb achieved the greatest reduction in the lepidoptera population. Seed treatment with the active ingredients used in this study is an effective practice for the control of Spodoptera frugiperda, Spodoptera cosmioides and Agrotis ipsilon caterpillars during the initial stage of soybean cultivation.

The aim of this paper is to present an alternative state observer structure for online estimation purposes of the key dynamical variables in a class of batch culture for plasmid production; the latter has been extremely attractive to be used as DNA vaccines or gene therapy. A mathematical model for culture of Escherichia coli DH5α-harboring plasmid was considered a benchmark system for the application of the proposed estimation methodology. Local observability analysis revealed that the system is partially observable for plasmid concentration considering only the biomass concentration in the batch culture as the measured variable. The proposed observer is designed with a simple proportional–integral feedback of the measured biomass concentration, where under the proposed design, the observer gain´s array can compensate the main nonlinearities of the estimation error dynamics. The convergence of estimated variables to the real ones is mathematically analyzed, reaching an asymptotic behavior. Numerical experiments were performed, where a comparison with a standard extended Luenberger observer was done and the proposed estimation methodology revealed a satisfactory performance.

The limited literature on sexual assault and unwanted sexual contact indicates that students with disabilities, and specifically students with Autism Spectrum Disorder (ASD), are an at risk population. This study uses data from a multi-institution climate assessment to examine the prevalence of unwanted sexual contact. Findings indicate that students with non-ASD disabilities and students with ASD were twice as likely to report unwanted sexual contact, than their nondisabled peers were. Women students with ASD are particularly at risk. Implications for postsecondary institutions, recommendations for student affairs professionals, and areas for future research are discussed.

We report on vertically stacked gate-all-around (GAA) Si nanowire (NW) MOSFETs, integrated in a CMOS dual Work Function Metal Replacement Metal Gate (RMG) flow. The integration of a lower temperature STI module and a SiN liner, designed to mitigate the oxidation-induced NW size loss and improve the width/height aspect ratio and NW controllability, is validated electrically. Additionally, Si GAA devices with reduced vertical nanowire spacing are demonstrated. The challenges in terms of Work Function Metal thickness scaling are highlighted, and a thinner nMetal process with low V TH capability and no J G /PBTI lifetime penalty is proposed. Electrically, these process innovations lead to a large improvement of I ON /I OFF performance and short channel margin. Finally, a ring oscillator circuit demonstration is shown, with a improvement of gate delay from 24ps down to 10ps at matched V DD demonstrated.

Chromatographic techniques are used in the purification step of human recombinant erythropoietin production process to obtain a reliable product with high purity. Anion-exchange chromatography supports have proved high efficient in removing contaminants such as DNA. For that reason, the DNA removal was determined by spike studies, on three anion-exchange chromatographic supports: gel, membrane, and monolithic column, which is used in intermediate purification stage. This study showed that membrane and monolith columns have very good results in the removal of contaminants at this step. Log removal values (LRV) greater than 3.5 were obtained from DNA spike clearance studies. Monolithic column was determined as the best technological proposal, with more than 4 LRV, 7.72 mg DNA per milliliter of adsorbent and 85% protein recovery in nonspike run. The results of this study may be used as a guide in the selection of commercially available chromatography supports for intermediate purification steps in re...

The authors examine the social construction of language, labels, and knowledge associated with disabilities, arguing in favor of critical and intersectional perspectives on disability identity.

Chía (Salvia hispanica L.) seed contains more oil and protein than other grains, has a high content of omega-3 linolenic acid, essential for human nutrition. Paraguay is currently among the five largest chía producer countries in the world, with 80 000 ha planted in 2013. The experiments were carried out during the months of March and October of 2017, the field work was made in the district of Chore-San Pedro, Paraguay departament, and laboratory evaluations in the Seed Analysis and Quality Laboratory of Agrarian Sciences, National University of Asunción-Paraguay. The objective of this investigation was to determine the physiological quality effect on chia seeds with differents paraquat moments application. The variables study consisted in evaluate the seeds germinative power, calculate the vigor by measuring length of seedlings and accelerated aging, also estimate different harvest times yield. The randomized complete blocks design was used with 4 treatments with 4 repetitions. The obtained results were analyzed by ANOVA and the means were compared using the Tukey test at 5% probability. The Paraquat herbicide was applied as a desiccant to accelerate and standardize the chia harvest at different maturing times, called as early, middle and late. In all the analyzed variables it is shown that the early application obtained the best results concluding that the application of paraquat in early harvest favors the yield and the final quality of the seeds.

The human consumption of vegetables in different parts of the world is quite high, among them tomato stands out on a larger scale and not so far, also is cucumber, both with great economic importance. Due to the problems regarding the vigor of many seeds, techniques that seek to improve the establishment of the seedlings in a uniform way have been implemented. One technique is the osmotic conditioning to which the seeds are submitted, for which compound solutions such as polyethylene glycol or potassium nitrate can be used, with which very satisfactory results are obtained under laboratory and field conditions The objective of this investigation was to evaluate the effect of different doses and osmotic solutions on the physiological quality of seeds of tomato (Solanum lycopersicum L.) and cucumber (Cucumis sativus L.) in laboratory and field conditions. The evaluated variables were germination percentage, germination speed index, root length and emergence of seedlings. The tomato seeds were conditioned with PEG-6000 (-0.2, -0.4, -0.6 and -0.8 Mpa) and stored for a 30 days period, and as for the cucumber seeds with PEG-6000 (-0.2 and -0.1 Mpa) and with KNO³ (100 mg and 300 mg) with a storage period of 45 days. It is concluded that, in tomato seeds, germination did not present statistical differences, however, the variables referring to vigor were favored with the conditioning in the presence of PEG-6000 with the (-0.2 Mpa) concentration, while in cucumber seeds the germination percentage was better using PEG 6000 compared to nitrate, while for vigor variables it behaved better in the presence of a concentration of (-0.2 Mpa) of PEG.

The aim of this paper is to study the stability, controllability and observability for a bioethanol production dynamic system. Likewise, a novel model based on the mechanism of multiple parallel coupled reactions was used to describe the kinetics of substrate, enzyme, and biomass and product formation. This model has been extended to continuous operation, which is employed as a virtual plant to enable the implementation of the properties. The maximum ethanol production conditions are obtained by manipulating the dilution rate with an optimal initial substrate concentration. A nonlinear observer is implemented to show the results of the observability analysis. Sufficient and necessary conditions for state controllability and state observability of such system are established. Results indicated that the proposed model can be applied as a way of augmenting bioethanol production, controlling and monitoring the process.

This work presents Si/SiGe superlattice finFETs (FF) for 1.8V/2.5V I/O applications in vertically-stacked Gate-All-Around horizontal nanowire technology (hNW) technology. Superlattice FF have a higher ION than I/O hNW reference devices and can be more easily integrated into a GAA hNW technology than Si I/O FF. These novel I/O FET structures exhibit competitive analog performance and are superior as ESD protection devices.

The distal radius fracture represent until 15% of all bone injuries in adults. The key in the recovery of mobility and functional outcomes are rehabilitation. The intra-articular application of magnesium sulphate has been used for postoperative pain. The objective was to determinate the improvement in pain and functional outcome of patients with distal radius fracture using intra-articular magnesium sulphate.Patients with distal radius fracture treated with percutaneous pinning and cast immobilization was included and randomized into two groups. The group 1 was applied 1.0 ml of magnesium sulphate and 1.5 ml of injectable water; meanwhile the group 2, the water was replaced with 1 ml of bupivacaine (5 mg/ml). The intra-articular infiltration was applied at the end of immobilization. Pain, functionality and movement of the wrist was evaluated for two weeks.Twenty patients, 8 male and twelve females, with a mean age of 53 years (± 17 SD) was evaluated. A significative reduction of pain during the first minute and at three minutes after intra-articular infiltration in group 2 (p 0.05). Both groups presented better articular outcomes at the two weeks (p 0.05), and a better articular movement at same point (p 0.05).The intra-articular infiltration of magnesium sulphate plus bupivacaine help to reduces the pain.Las fracturas de radio distal constituyen hasta 15% de todas las lesiones óseas en los adultos. La rehabilitación es clave en la recuperación de la movilidad y la capacidad funcional. El sulfato de magnesio intraarticular ha sido utilizado para control postoperatorio del dolor; el objetivo fue determinar la mejoría del dolor y la capacidad funcional de los pacientes con fractura de radio distal usando sulfato de magnesio intraarticular.Pacientes con fractura de radio distal tratados con clavos percutáneos e inmovilización fueron incluidos al azar en dos grupos. Grupo 1 infiltrado con 1.0 ml de sulfato de magnesio y 1.5 ml de agua estéril; en el grupo 2 esta última fue sustituida por 1 ml de bupivacaína (5 mg/ml). La infiltración se realizó al retiro de la inmovilización. El dolor, funcionalidad y rangos de movimiento fueron evaluados.20 pacientes, ocho masculinos y 12 femeninos con edad promedio de 53 años (± 17 DE) fueron evaluados. Se encontró disminución significativa en el dolor al primer minuto y a los tres minutos después de la infiltración en el grupo 2 (p 0.05). Ambos grupos presentaron una mejoría significativa en la funcionalidad articular a las dos semanas (p 0.05), así como una mejoría gradual en la movilidad articular en ese mismo período (p 0.05).La infiltración de sulfato de magnesio en combinación con bupivacaína ayuda a disminuir el dolor.

The Editors-in-Chief are retracting this article [1]. After publication concerns were raised with respect to inconsistencies between this trial protocol and the trial registry entry. Subsequent investigation has shown that patient recruitment had been completed before submission of the protocol to the journal, which is a breach of the journals editorial policy. Concerns have also been raised that one of the reviewers was added to this article as an author after revision. Michele Carenini and Wendy Moreno Pea agree with this retraction and Angelo Compare does not agree with this retraction. Vassilis Kouloulias, Vontas Apostolos, Enrico Molinari, Enzo Grossi and Efstathopoulos Efstathios did not reply to correspondence about this retraction. © 2018 The Author(s).

We report on CMOS-integrated vertically stacked gate-all-around (GAA) Si nanowire (NW) MOSFETs with in-situ doped source-drain stressors and dual work function metal gates. We demonstrate that oxidation-induced SiGe/Si fin deformation by STI densification is effectively suppressed by a SiN liner. This SiN fin protection improves the controllability of nanowire formation. In addition, highly-selective Si nano-wire release and inner spacer cavity formation without Si re-flow are demonstrated. Finally, for the first time we report functional ring oscillators based on stacked Si NW-FETs.

An increasing number of institutions utilize social media tools, including student-written blogs, on their admission websites in an effort to enhance authenticity in their recruitment marketing materials. This study offers a framework for understanding what contributes to prospective college students’ perceptions of social media authenticity and how their perceptions shape expectations of the college experience. The results of the study are based on qualitative data comprising 16 in-depth interviews, 165 journal entries, and an eight-member focus group interview with college-bound students. Prospective college students perceived student-written blogs to be authentic when student bloggers disclosed personal details and feelings about campus life, even when the topic of the blog was contrived to focus on admission and college-related activities. Recognizing a blog as authentic occurred through the process of internalizing the experience described in the blog post and identifying with the blogger.

The purpose of this grounded theory study was to explore how lived experiences affect ethnic identity development of transracial Korean American adoptees raised by White parents with the intent of informing higher education practice. Participants included 12 recently college-graduated transracial Korean American adoptees who were raised in the Midwest, rural south, and on the west coast. A theoretical model that surfaced from data collection is presented, demonstrating the complexity of transracial Korean adoptee identity.

This study investigates faculty members' experiences in a 20-month inquiry project that provided them with structured opportunities to (a) interview students of color about their educational journey, and (b) meet with other faculty members as a collaborative inquiry team to discuss student interview findings. Changes in faculty members were documented through faculty interviews, observations of inquiry meetings, and faculty's reflective journal entries. Findings revealed that faculty members developed an intimate knowledge of students' experiences coupled with an understanding of the broader social implications of being a student of color. They developed a critical consciousness and practical knowledge that informed more responsive approaches with students.

En la provincia de Tungurahua las PYMES no son ajenas a estos problemas pues además se les debe sumar aquellos de carácter estructural y coyuntural que inciden en la condición de factores de la producción, además los inadecuados métodos de gestión hacen imposible su crecimiento. Tungurahua es una provincia central que mantiene un PIB del 1.87 y por ende su ubicación geográfica es privilegiada por lo que la aplicación de estrategias de crecimiento se vuelve en fortalezas a aprovechar. Para este análisis se utilizó la empresa Inverneg S.A que tiene una cobertura hacia las provincias de Tungurahua, Cotopaxi, Bolívar, Chimborazo y Pastaza. Teniendo en cuenta que cubre a varias provincias cuenta con seis vendedores externos que tienen dificultades en el proceso de venta y últimamente en el decrecimiento de las ventas, para ello se utilizó un enfoque mixto que analice las realidades subjetivas a través de un cuestionario estructurado que responda a los constructos en estudio, luego de aplicado el estadígrafo chi cuadrado se verifico la hipótesis alternativa que manifiesta que las estrategias de crecimiento inciden en el volumen de ventas de la empresa, dando como conclusión que las empresas que no planifican y calculan sus recursos para desarrollar las estrategias se quedan estancadas y a largo tiempo tienden a desaparecer del mercado.

Chromatin dynamics regulates diverse nuclear processes and influences cellular viability and tumorigenesis. The discrete chromatin states are linked to covalent histone modifications that control the extent of DNA accessibility to transacting factors. One of the most common epigenetic modifications is methylation of histone H3 at lysine 4 (H3K4). Lys4 can be mono-, di-, or tri-methylated, and the tri-methylated mark (H3K4me3) is normally associated with euchromatin and active gene transcription.1,2 The inhibitor of growth (ING) family of tumor suppressors contain a C-terminal plant homeodomain (PHD) finger. This conserved zinc-binding module is found in many nuclear proteins including transcription factors, histone modifying enzymes, and ATP dependent chromatin remodeling complexes.3-5 A subset of PHD fingers has recently been shown to bind methylated and unmodified histone tails,5-9 with the H3K4me3 mark being specifically recognized by ING proteins. Unlike ING1 and ING2, which have been identified as components of histone deacetylase (HDAC) complexes, ING5 associates with histone acetyltransferase (HAT) complexes containing MOZ (monocytic leukemia zinc finger protein)/MORF (MOZ-related factor) and HBO1.10 To establish the structural basis of chromatin targeting by the HAT associated ING proteins, we determined the crystal structure of the ING5 PHD finger in complex with its histone target (H3K4me3). We also measured binding affinities for unmodified, mono-, di-, and tri-methylated histone peptides, and showed that both full-length ING5 and methylated H3K4 are essential for the acetyltransferase activity of the MOZ/MORF and HBO1 complexes. This functional data are the first direct evidence supporting the critical role of ING5 in directing the MOZ/MORF and HBO1 complexes to chromatin, which consequently increases the local HAT activity and stimulates chromatin remodeling.

Inhibitor of growth 1 (ING1) is implicated in oncogenesis, DNA damage repair, and apoptosis. Mutations within the ING1 gene and altered expression levels of ING1 are found in multiple human cancers. Here, we show that both DNA repair and apoptotic activities of ING1 require the interaction of the C-terminal plant homeodomain (PHD) finger with histone H3 trimethylated at Lys4 (H3K4me3). The ING1 PHD finger recognizes methylated H3K4 but not other histone modifications as revealed by the peptide microarrays. The molecular mechanism of the histone recognition is elucidated based on a 2.1 A-resolution crystal structure of the PHD-H3K4me3 complex. The K4me3 occupies a deep hydrophobic pocket formed by the conserved Y212 and W235 residues that make cation-pi contacts with the trimethylammonium group. Both aromatic residues are essential in the H3K4me3 recognition, as substitution of these residues with Ala disrupts the interaction. Unlike the wild-type ING1, the W235A mutant, overexpressed in the stable clones of melanoma cells or in HT1080 cells, was unable to stimulate DNA repair after UV irradiation or promote DNA-damage-induced apoptosis, indicating that H3K4me3 binding is necessary for these biological functions of ING1. Furthermore, N216S, V218I, and G221V mutations, found in human malignancies, impair the ability of ING1 to associate with H3K4me3 or to induce nucleotide repair and cell death, linking the tumorigenic activity of ING1 with epigenetic regulation. Together, our findings reveal the critical role of the H3K4me3 interaction in mediating cellular responses to genotoxic stresses and offer new insight into the molecular mechanism underlying the tumor suppressive activity of ING1.

We report large magnetoresistance in ferromagnet/superconductor/ferromagnet structures made of La 0.7 Ca 0.3 MnO 3 and YBa 2 Cu 3 O 7 at temperatures along the resistive transition. We find that the magnetoresistance phenomenon is independent on the orientation of electric current versus field. Furthermore, the effect is also independent on the sweep rate of the magnetic field. This excludes interpretations in terms of spontaneous vortices or anisotropic magnetoresistance of the ferromagnetic layers and supports the view that the magnetoresistance phenomenon originates at the spin-dependent transport of quasiparticles transmitted from the ferromagnetic electrodes into the superconductor.

We have found large magnetoresistance in ferromagnet/superconductor/ferromagnet heterostructures made of La0.7Ca0.3MnO3 and YBa2Cu3O7. It originates at an increase of the width of the resistive transition when the magnetizations of the ferromagnetic layers are aligned antiparallel. We find that the shape and height of the magnetoresistance peaks are not modified when the angle between current and magnetic field is changed from parallel or perpendicular. Furthermore, we find that the temperature shift of the resistance curves is independent of the current values. This favors the view that the magnetoresistance phenomenon originates at the spin dependent transport of quasiparticles transmitted from the ferromagnetic electrodes into the superconductor, and rules out interpretations in terms of spontaneous vortices or anisotropic magnetoresistance of the ferromagnetic layers.

The defense budget can be reduced and the U.S. military downsized because (1) the nation-state threat environment is markedly different than it was during the Cold War, and (2) a large military is not necessary to combat the terrorist threat. In fact, the Islamist terrorist threat is relatively undeterred by the U.S. military presence abroad, and U.S. forces abroad, particularly those deployed in Muslim countries, may do more to exacerbate than to diminish the threat. The arduous task of dismantling and degrading the terrorist network will largely be the task of unprecedented international intelligence and law enforcement cooperation, not the application of large-scale military force. To the extent the military is involved in the war on terror, it will be special forces in discrete operations against specific targets rather than large-scale military operations.

We have investigated the effect of magnetic spacer on the coupling properties in YBa 2 Cu 3 O 7 /La 0.3 Ca 0.7 MnO 3 superconducting/ferromagnet superlattices. Scaling analysis of the angular dependence of the magnetoresistance in the liquid state reveals a decoupled vortex liquid, as confirmed the magnetic field dependence of the activation energy for vortex motion. This result is discussed in terms of weak superconducting coherence along the c -direction resulting of pair breaking by spin polarized carriers.

Magnetic and transport properties are investigated in epitaxial La0.67Ca0.33MnO3 thin films grown on SrLaAlO4 under high in plane compressive strain (K3.1%). Films with thickness in the range 2‐6.5 nm show a two dimensional coherent growth mode and are significantly strained as shown by the expansion of the out of plane lattice parameter. We provide evidence for phase separation induced by the inhomogeneous strain field, free of artefacts related to composition changes at grain boundaries or structurally disordered regions characteristic of island growth. q 2005 Elsevier Ltd. All rights reserved.

We examine the interplay between ferromagnetism and superconductivity in La0.3Ca0.7MnO3/YBa2Cu3O7 superlattices showing “coexistence” of magnetism and superconductivity. A depression of the critical temperature is observed when manganite layer thickness is increased between 0.9 and 8 nm, pointing to an interplay between ferromagnetism and superconductivity over nanometer length scales. The possibility of a ferromagnetic/superconducting proximity effect to explain these results is analyzed.

Driven by the global concern about radon hazards, a wide variety of methods to measure radon and its decay products have been developed. Pin silicon photodiodes are increasingly applied in this field, their main advantages being high detection efficiency for alpha particles and low cost. In this paper, we present a system to determine the emanation factor for 222 Rn from porous material based on a pin photodiode. This equipment is valid both for field and laboratory measurements, allowing to monitor the external emanation conditions by means of temperature, humidity and pressure sensors. To illustrate the capabilities of the system, we present two case studies of samples with high and low 226 Ra content. The activity of this radionuclide in the samples had been previously determined by γ-ray spectrometry.

We present electrical conductivity measurements of BIFEVOX Bi4V2-xFexO11-y (0≤x≤0.9; 0≤y≤1), in which V (IV) ions have been systematically substituted by Fe (III) ions. Conductivity shows a power law frequency dependence described by the form σ*(ω)=σdc[1+(jω/ωp)n], known as universal dynamic response. Conversely, the electric modulus shows asymmetric peaks, characterized by stretched exponentials relaxation functions in time domain of the form φ(t)=exp(-(t/τσ)β). β is determined by the degree of correlation in the ionic motion. It´s value, β=0.56±0.03, is almost independent of temperature and iron content. Increasing Fe content leads to an exponential decrease of the conductivity and to an increase of the activation energy of the conduction process from 0.20 to 0.97 eV. These results are discussed in terms of oxygen vacancy ordering upon Fe (III) substitution.Presentamos medidas de la conductividad eléctrica del sistema BIFEVOX Bi4V2-xFexO11-y (0≤x≤0.9; 0≤y≤1), en el que se realiza la sustitución de iones V (IV) por Fe (III) de forma sistemática. La conductividad muestra un comportamiento potencial con la frecuencia, descrito por σ*(ω)=σdc[1+(jω/ωp)n], y conocido como respuesta dieléctrica universal. Análogamente, el módulo eléctrico presenta picos asimétricos, cuya función de relajación en el dominio del tiempo puede describirse mediante exponenciales “estiradas” de la forma φ(t)=exp(-(t/τσ)β). β da cuenta del grado de correlación del transporte iónico, siendo su valor, β=0.56±0.03, casi independiente de la temperatura y del contenido en Fe. Con el aumento en el contenido de Fe, la conductividad disminuye exponencialmente y la energía de activación del proceso de conducción aumenta de 0.20 a 0.97 eV. Estos resultados se discuten en términos de la ordenación de vacantes oxígeno al dopar con Fe (III).

Correlation effects in the ionic conductivity of BIFEVOX (Bi 4 V 2-x Fe x O 11-y , 0 ≤ x ≤ 0.9, 0 ≤ y ≤ 1) by impedance spectroscopy measurements have been investigated. The real part of the conductivity shows power-law frequency dependence at high frequencies, and electric modulus plots show asymmetric peaks, as a consequence of correlations in the oxygen ion diffusion. Relaxation functions in the time domain are well-described by stretched exponentials of the form o(t) = exp(-(t/τ σ ) β ), with an exponent β = 0.56 ± 0.03, which is nearly independent of temperature and Fe content. It is found that the room temperature dc conductivity decreases exponentially when Fe content is increased and the dc conductivity activation energy increases from 0.20 to 0.97 eV. Results are discussed in terms of oxygen vacancy ordering upon Fe substitution in V sites.

Good process control has been often criticized for the economic viability of large-scale production of several commercial products. In this work, the production of biodiesel from microalgae is investigated. Successful implementation of a model-based control strategy requires the identification of a model that properly captures the biochemical dynamics of microalgae, yet is simple enough to allow its implementation for controller design. This paper explores the biodiesel production in a class of continuous culture under heterotrophic conditions via closed-loop operation. A mathematical model adapted from Surisetty et al. (2010) that describe the growth of microalgae in a heterotrophic culture is studied via dynamic analysis. This model is extended to continuous operation where bifurcation analysis were carried out for the determinate the qualitative model behavior and to analyze feasible operating conditions. This project is focused on the on the use of a mixture of two substrates that are continuously fed into the reactor chamber and the continuous fermentation process is described by an unstructured mathematical model with a product inhibition on cell growth. In addition, we present the design of a nonlinear control law contains a class of bounded-type feedback of the named control error in order to regulate the substrate concentration at maximum value to lead indirectly the lipids-diesel concentration. Lipid productivity in continuous culture was 0.276 g /L d, which was an increase of 18.1% over that of the batch mode. Finally, numerical experiments proved satisfactory performance of the proposed methodology in comparison with linear PI controller.

To show that patients with intertrochanteric fractures treated with a proximal femoral nail have a better postoperative course than those treated with a DHS plate (dynamic hip screw).Patients with a BoydGriffin type II intertrochanteric fracture were randomly divided into two groups: a group of patients treated with a PFN and another one treated with a DHS plate. All patients were assessed at 2, 4, 8 and 16 weeks using the Harris scale and the visual analog scale pre- and postoperatively, as well as the operative time, incision size, intraoperative bleeding, onset of partial and/or total weight bearing, healing time, time to attain prior physical activity level, and radiographic result.32 patients met our criteria. The variables that had a significant reduction were: incision, operative time, postoperative pain according to the visual analog scale, onset of mobility, partial weight bearing and pain at 2 weeks.The proximal femoral nail has better short-term outcomes than the DHS plate; however, in the medium term both implants have the same outcomes.