Yeda Research and Development (Israel)

Abstract Alzheimer’s disease (AD) is characterized by toxic protein accumulation in the brain. Ubiquitination is essential for protein clearance in cells, making altered ubiquitin signaling crucial in AD development. A defective variant, ubiquitin B + 1 (UBB +1 ), created by a non-hereditary RNA frameshift mutation, is found in all AD patient brains post-mortem. We now detect UBB +1 in human brains during early AD stages. Our study employs a 3D neural culture platform derived from human neural progenitors, demonstrating that UBB +1 alone induces extracellular amyloid-β (Aβ) deposits and insoluble hyperphosphorylated tau aggregates. UBB +1 competes with ubiquitin for binding to the deubiquitinating enzyme UCHL1, leading to elevated levels of amyloid precursor protein (APP), secreted Aβ peptides, and Aβ build-up. Crucially, silencing UBB +1 expression impedes the emergence of AD hallmarks in this model system. Our findings highlight the significance of ubiquitin signalling as a variable contributing to AD pathology and present a nonclinical platform for testing potential therapeutics.

Abstract Separation of metallic single‐walled carbon nanotubes (m‐SWNTs) using various amines in different concentrations was investigated. The SWNTs dispersions were characterized with Vis–NIR and Raman spectrometers. The proportion of m‐SWNTs toward semiconducting SWNTs increased with an increase of concentration of amines. SWNTs thin films were prepared from the SWNTs dispersion. The sheet resistance of SWNTs films decreased with an increase of proportion of m‐SWNTs.

Probablemente uno de los mayores retos a la hora de abordar la ansiedad sea delimitar adecuadamente lo que el constructo abarca. El propósito de este trabajo es realizar una revisión del constructo ansiedad en la psicología a fin de contribuir en su delimitación. En primer lugar, se examina el origen del término ansiedad y se lo discrimina de otros términos coincidentes o estrechamente relacionados como angustia, miedo y estrés. A continuación, se realiza un recorrido histórico sobre el concepto ansiedad y su evolución en la psicología hasta arribar a la conceptualización más actualizada. Finalmente adoptando como marco teórico la teoría cognitiva de la ansiedad (Clark & Beck, 2012), se delimita el constructo ansiedad y se realiza una diferenciación entre ansiedad normal, ansiedad como rasgo de personalidad y ansiedad patológica.

Since adult stem cells are responsible for replenishing tissues throughout life, it is vital to understand how failure to undergo apoptosis can dictate stem cell behavior both intrinsically and non-autonomously. Here, we report that depletion of pro-apoptotic Bax protein bestows hair follicle stem cells with the capacity to eliminate viable neighboring cells by sequestration of TNFα in their membrane. This in turn induces apoptosis in "loser" cells in a contact-dependent manner. Examining the underlying mechanism, we find that Bax loss-of-function competitive phenotype is mediated by the intrinsic activation of NFκB. Notably, winner stem cells differentially respond to TNFα, owing to their elevated expression of TNFR2. Finally, we report that in vivo depletion of Bax results in an increased stem cell pool, accelerating wound-repair and de novo hair follicle regeneration. Collectively, we establish a mechanism of mammalian cell competition, which can have broad therapeutic implications for tissue regeneration and tumorigenesis.

<p align="justify">Este artículo es resultado de la investigación interinstitucional entre el Doctorado en Educación de la Universidad Santo Tomás y la Universidad San Buenaventura de Cali, programa de Maestría en Educación: Desarrollo Humano y el proyecto de Doctorado en Educación. Se hace una síntesis de lo que se encontró a través de la búsqueda en los documentos de los doctorados en educación en Colombia, durante el periodo 2000-2010, con relación a las investigaciones sobre ciencia, tecnología y sociedad, y sus aportes a la consolidación de las teorías pedagógicas con impacto en el desarrollo social del país.</p>

Abstract A number of methods of synthesis of methanol labelled with 18 O or with 17 O have been evaluated. The best method is considered to be the partial hydrolysis of trimethyl phosphate. Ethanol‐ 18 O can be prepared analogously by the partial hydrolysis of triethyl phosphate. The most accurate method for the isotopic analysis of oxygen in methanol is by pyrolysis in a specially designed vessel, the hydrogen being extracted through a palladium tube and the residual carbon monoxide analysed mass‐spectrometrically.

The wide variety of nest architectural designs exhibited by passerine birds allowed them to diversify into a wide variety of ecological niches and terrestrial habitats. At present, very little is known about the mechanics of building these structures. Digitizing natural biological structures such as bird nests provides the opportunity to explore their structural properties and behavior under specific conditions by means of computational manipulations, simulations, and analyses. This study describes a generic algorithm for the digitization and exploration of complex interlocked bird nests, and validates it on nests built by the Dead-Sea Sparrow (Passer moabiticus) in branches of trees using stiff dry branches. This algorithm takes as input computerized tomographic scans of the nest, identifies and isolates each branch entity within the three-dimensional data, and finally extracts the characteristics of each branch. The result is a reliable three-dimensional digital model of the nest that contains a complete geometric dataset per each of its components, e.g. dimensions and contact points with neighboring components, as well as global properties, e.g. density distribution and network structure. Based on these, we were able to simulate various models of the nest construction process. Altogether, the described algorithm and possible derivatives thereof could be a valuable tool in studying the structure-function relationships of similarly complex biological objects, and may provide further insights into the potential selective mechanisms underlying historical evolution of this distinct nest form.

OBJECTIVE: To evaluate the effect of ventral cardiac denervation in the incidence of atrial fibrillation after coronary artery bypass surgery. METHODS: Between September and November, 50 patients without history or previous diagnosis of atrial arrhythmia from the same institution presenting coronary heart disease with indication for coronary artery graft bypass surgery were enrolled in a prospective and randomized study. The exclusion criteria were: patients older than 75 years of age, previous history of atrial arrhythmia and associated heart surgeries. Denervation was performed before cardiopulmonary bypass and it was achieved by removing the adipose tissues around the superior vena cava, aorta and pulmonary artery. The groups were compared regarding demographic, clinical and operative variables. RESULTS: There were no hospital mortalities. The additional time for the denervation was 7.64+/-2.33 minutes, and there were no associated complications. Postoperative atrial fibrillation was present in two (8%) patients of the Control Group and in three (12%) patients who underwent ventral cardiac denervation. The risk of postoperative atrial fibrillation in patients undergoing ventral cardiac denervation was 22% higher than in the Control Group (0.56-2.66,confidence interval); however, this outcome was not statistically significant (p=0.64). CONCLUSION: Ventral cardiac denervation, despite being a fast and low-risk procedure, does not significantly reduce the incidence of atrial fibrillation after coronary artery bypass graft surgery.

Steel Bearing Wall with Slits has been proved to be an earthquke-resisting element with high energy absorption capacity through experiments, and the design formulae we had proposed showed good agreement to the test results. Those experiments, however, focused on the wall's behavior with an idealized boundary condition. In this paner, the experiment on the steel building frame with steel bearing wall with slit is shown. This paper aims to make dear the behaviors and the mutual effects of the wall and the frame when attached to each othe, and to check the applicability of the proposed design formulae.

Additional earthquake-resisting elements are frequently used to cope with the lack of stiffness and energy absorption capacity that inevitably comes along with ever slenderized members utilized nowadays. Steel Bearing Wall with Slits, which is easily fabricated, is an earthquake-resisting element with high energy absorption capacity with the parts of the steel plate between slits behaving as columns. Its strength and stiffness are readily controlled by altering length or pattern of slits. Stating about the experiments we have conducted, this paper explains the behavior and proposes the design formula of strength and stiffness of the individual bearing wall.

La Asamblea Constituyente en Bolivia sin lugar a dudas es un hito histrico constitutivo por su amplio carcter de participacin, deliberacin pblica e intencionalidad poltica de refundar el Estado. No obstante los numerosos obstculos en el desarrollo del proceso 1 , en la construccin sustantiva de su contenido el movimiento indgena campesino, otros actores sociales, la bancada mayoritaria y sus aliados, lograron consensuar y concretar propuestas de articulado. Uno de las principales grupos de la sociedad civil que tuvo una participacin activa fue la de los pueblos indgenas de tierras bajas. Desde una movilizacin nacional el ao 2002, plantearon la necesidad de convocar a una Asamblea Constituyente como camino para resolver problemas estructurales que provocaban una crisis sostenida de ingobernabilidad. La estrategia seguida por estos estuvo centrada en la bsqueda de aliados a su causa. En este contexto, aparece el emblemtico acuerdo, denominado Pacto de Unidad por la Asamblea Constituyente. En esta plataforma se elabor, posicion y defendi una propuesta de nueva Constitucin

El objetivo de esta investigación fue estudiar las prácticas de los comerciantes de la industria del calzado del municipio de San José de Cúcuta que puedan ser elevadas a la categoría de costumbres mercantiles conforme al artículo 3.º del Decreto 410 de 1971. Se trató de una investigación de tipo descriptivo y sociojurídico enmarcada en el paradigma histórico-hermenéutico y el enfoque cualitativo, en la que participaron 280 comerciantes/fabricantes de calzado. Se utilizaron como instrumentos una entrevista estructurada y un cuestionario en dos etapas diferentes. Los resultados permitieron identificar seis prácticas que cumplen con los requisitos de publicidad, uniformidad, reiteración y convicción de obligatoriedad.

Probablemente uno de los mayores retos a la hora de abordar la ansiedad sea delimitar adecuadamente lo que el constructo abarca. El propósito de este trabajo es realizar una revisión del constructo ansiedad en la psicología a fin de contribuir en su delimitación. En primer lugar, se examina el origen del término ansiedad y se lo discrimina de otros términos coincidentes o estrechamente relacionados como angustia, miedo y estrés. A continuación, se realiza un recorrido histórico sobre el concepto ansiedad y su evolución en la psicología hasta arribar a la conceptualización más actualizada. Finalmente adoptando como marco teórico la teoría cognitiva de la ansiedad (Clark & Beck, 2012), se delimita el constructo ansiedad y se realiza una diferenciación entre ansiedad normal, ansiedad como rasgo de personalidad y ansiedad patológica.

The surface anionic site distribution on membranes of a monoclonal antibody-producing hybridoma cell line, and its two parental cells: normal spleen cells of immunized BALB/c mice and cells from a mouse myeloma line (NS-1), were investigated with the aid of the cationized ferritin (CF) labelling method, following glutaraldehyde/formaldehyde fixation of cells. The patch-like CF distribution on the hybridoma cells is similar to that of the NS-1 myeloma cells, but distinct from the even and continuous CF distribution of the immunized and nonimmunized normal spleen lymphocytes. The similarity in the formation of patch-like CF heaps, both on myeloma and hybrid cells is discussed in respect to the surface charge characteristic determined by cell fusion.

The monitoring of ship propulsion equipment requires sensors that are intelligent, miniaturized, and low-power. However, traditional wired and battery-based power supplies restrict the reliable deployment and long-term operation of these sensors. This paper proposes a high-power triboelectric-electromagnetic rotational energy harvester adapted for low-speed conditions. The device uses a double-rotor structure to simultaneously increase the axial triboelectric area and enhance the magnetic flux density, improving the energy conversion efficiency of both the triboelectric nanogenerator (TENG) and the electromagnetic generator (EMG). The system includes two TENGs and one EMG sharing a rotor architecture for different operation modes. Experimental comparisons show that connecting TENGs in parallel yields a better electrical output than series connections. At 150 rpm, the TENG delivers a peak open-circuit voltage of 487.02 V, a short-circuit current of 13.10 μA, and a peak power of 6.11 mW under impedance matching, while its power density is 4.03 W·m–3, compared to 350.42 W·m–3 for the EMG under the same conditions. At 300 rpm, the TENG and EMG achieve peak open-circuit voltages of 850.72 and 51.06 V, and peak short-circuit currents of 22.1 μA and 396.3 mA, respectively. This integrated system, combining triboelectric and electromagnetic energy harvesting, successfully provides self-powered shaft monitoring, offering a solution for the development of intelligent, low-power ship systems.

Through compressive test on 18 polyurethane composite panels in 4 groups, observing their failure characteristics under compression, getting test result on compressive performance and load-deformation curve, analyzing failure reason, which will set the foundation for further experimental study and theoretical analysis.

Abstract. The production of antisera to HAA in donkeys is described. The antiserum is produced by the injection of antigen‐antibody complexes and is of use in diagnostic laboratories for detecting HAA‐positive sera.

<i>Background: </i>Histamine, a major mediator in endogenous and exogenous skin disorders, has been extensively investigated. Many experiments concern external provocation, yet the sequence of events as well as the influence of timing of the provocating factors require clarification. <i>Objective:</i> To document cutaneous reactivity to histamine rechallenge at different time points, as well as the response of irritated skin (irritant dermatitis) to histamine. <i>Methods:</i> Histamine was intradermally administered on the upper back of 20 volunteers at different time points to 3 sites and following SLS-induced irritant dermatitis to another site. The cutaneous vascular response was measured by laser Doppler flowmetry. <i>Results: </i>The response to a second prick when the first prick response had decayed to half its peak was significantly higher than all the other responses that resulted from a second prick (p < 0.01). The other responses did not significantly differ from each other or from the first prick response. When the histamine prick was performed over a 24-hour SLS patch, the response was greater than at all other sites (p < 0.01). <i>Conclusion:</i> An excitation state, at which the skin readily reacted to the second insult, may underlie the augmentation of the response to a histamine prick over the irritated skin. Irritation modulates cytokines, which may be the mechanism by which the response to histamine administration is enhanced. Tachyphylaxis did not occur at the time points tested, but may occur at longer intervals, necessitating further investigation.

La presente investigación se realizó en las instalaciones de la Estación Experimental Portoviejo del INIAP entre la época seca del 2008 y la época lluviosa del 2009, tuvo como objetivos: determinar la duración del ciclo biológico, el comportamiento bajo condiciones de laboratorio, y establecer la capacidad vectora de Dalbulus maidis sobre el complejo “Cinta Roja” (CR) en maíz como aporte de información local para investigaciones futuras sobre morfología, capacidad de oviposicion y fertilidad del insecto. Los resultados obtenidos demostraron en época lluviosa del 2009, que la hembra de D. maidis oviposita al pasar al estado adulto y relacionarse con el macho, ovipositando promedialmente 82 huevos durante su ciclo de vida, en temperatura promedio de 26.96°C y de humedad relativa de 80.39%. Los huevos eclosionan después de nueve días, luego se transforman en cinco estados ninfales que en promedio duran 25.61 días, pasando al estado adulto que tiene una longevidad en hembras de 44.85 días y en los machos 22.95 días. Se comprobó que es D. maidis un vector eficiente en la presencia de la enfermedad CR en plantas del híbrido de maíz INIAP H-552 (susceptible), la transmisión de la enfermedad se comprobó mediante tres metodologías adaptadas al medio. En la metodología más eficiente el promedio de hojas afectadas fue de 44.52% de síntomas del complejo CR, bajo condiciones de invernadero en época lluviosa, con temperaturas promedio de 28.51°C y humedad relativa de 79.22%.
 Palabras claves: Comportamiento, resultados, vector, metodología

Desde la perspectiva del metabolismo social, el proceso sociometabólico de apropiación se constituye en la forma primaria de intercambio entre la sociedad humana y la naturaleza. En este proceso, las sociedades se apropian de materiales, energías y servicios requeridos por los seres humanos y sus artefactos, desarticulando o desorganizando los ecosistemas y reorganizándolos con fines productivos. A partir de estas premisas, el presente análisis procuró dar cuenta de las principales transformaciones socio-ecológicas que tuvieron lugar en la Región Norte de Costa Rica, caracterizada por una incorporación lenta, tardía e incompleta al proyecto económico, social y político emanado desde el Valle Central. La explotación forestal primero, y la ganadería después, ambas actividades con una clara vocación comercial, se constituyeron en las alternativas económicas predominantes en la región, aún con marcadas diferencias intrarregionales. Esta “apropiación mercantilista” de la naturaleza, que se instauró desde los propios inicios de la colonización efectiva del territorio, trajo consigo profundas consecuencias ecológicas y ambientales, como la pérdida de biodiversidad, la simplificación de los ecosistemas, el empobrecimiento de nutrientes de los suelos, la reducción de las funciones ecológicas del bosque y, en general, la degradación de los ecosistemas.