588 research outputs found
Sorting networks implemented as νMOS circuits
A new realisation for n-input sorters is presented. Resorting to the neuron-MOS (νMOS) concept and to an adequate electrical scheme, a compact and efficient implementation is obtained.Comisión Interministerial de Ciencia y Tecnología TIC95-0094, TIC97-064
A practical floating-gate Muller-C element using vMOS threshold gates
This paper presents the rationale for vMOS-based realizations of digital circuits when logic design techniques based on threshold logic gates are used. Some practical problems in the vMOS implementation of threshold gates have been identified and solved. The feasibility and versatility of the proposed technique as well as its potential as a low-cost design technique for CMOS technologies have been shown by experimental results from a multiple-input Muller C-element. The proposed new realization exhibits better performance related to delay and area and power consumption than the traditional logic implementation
Fate of Artificially Injected Oxygen in the Hypolimnion of a Two-Basin Lake: Amisk Lake, revisited
The first author visited Texas A&M University funded by U.S. National Science Foundation
grant CBET 1033514. It was during that visit that, under the supervision of Scott Socolofsky, the
double-plume model was implemented into the 3D hydrodynamic model. Meteorological data
for Atmore AGDM station was provided by the Alberta Climate Information Service, found at
https://acis.alberta.ca. The data displayed in the figures can be accessed at
https://zenodo.org/record/4565311.Bubble-plume diffusers are increasingly used to add dissolved oxygen (DO) to the hypolimnion
of lakes and reservoirs. Bubble plumes are successful at replenishing hypolimnetic DO, but they
also introduce mixing energy that induces subtle changes in the thermal structure of the
reservoir, driving changes in plume behavior. To account for this complex plume-reservoir
interaction, a double bubble-plume model is coupled with a three-dimensional hydrodynamic
model. The coupled model is used to reassess a field-scale analysis of the bubble-plume diffuser
in two-basin Amisk Lake, aiming at evaluating the relative role of bubble-induced circulation
and internal-seiching in driving inter-basin transport under stratified conditions. A large-scale
plume-induced circulation was previously thought to be the main driver of inter-basin oxygen
transport. This interpretation was based on the attribution of the time-averaged circulation in the
channel due to plume operation. However, the intrinsic complexity of the hydraulic system and
the sparseness of the field data introduced large uncertainties in the previous analysis. Here, we
demonstrate that the time-averaged circulation is primarily the result of wind-driven internal
seiches. Oxygen exchange is shown to be controlled by the interaction between internal seichedriven
horizontal transport along the channel, and, the rate at which added oxygen reaches the
layers above the sill, which is mainly controlled by plume-induced circulation. Internal-seiche
driven transport through basin constrictions will vary depending on the magnitude of the wind
forcing, depth of the thermocline and the channel geometry. These results highlight the
importance of understanding water movement prior to introducing restoration actions in lakes.National Science Foundation (NSF) CBET 103351
CARACTERIZACIÓN DE EXOSOMAS PRODUCIDOS POR CÉLULAS OVIDUCTALES IN VIVO E IN VITRO, EN LA ESPECIE BOVINA
Recent studies have shown that extracellular vesicles may play an important role in modulating the fertilization capacity of sperm during their journey through the female reproductive tract. Extracellular vesicles (EVs), exosomes and micro vesicles, are a type of heterogeneous structures present in most body fluids, including bovine oviductal fluid. EVs contain various compounds derived from the original cell, such as proteins, lipids, mRNA, miRNA and DNA. EVs in the oviduct are produced by epithelial cells and their functions include interaction with spermatozoa, maintenance of their viability, participation in oocyte maturation and in the fertilization process.
During the in vitro fertilization process and in order to improve it by mimicking in vivo conditions, numerous researchers have used bovine oviductal epithelial cell (BOEC) cultures with remarkable improvements. These cells produce, among others components, VEs, for this reason, in this work we have proposed a comparative study of the EVs present in the bovine oviductal fluid (OF) collected at times close to ovulation (in vivo) and those produced in BOEC cultures after 7 days of culture (in vitro) comparing the size, population distribution and protein concentration in both types. The EVs were identified by electron microscopy, their size by laser light scattering and their protein concentration by Bradford's method.
The results showed that the EVs size evaluated per intensity were similar between both experimental groups. On the other hand, differences were observed in terms of protein concentration. EVs obtained in vivo contained a greater amount of protein in their cargo than the EVs obtained in vitro.Regarding the identification of VEs by transmission electron microscopy, only those obtained in vivo could be observed. This fact could be due to the place where they have been collected, to the method of culture of bovine oviductal epithelial cells or the shortage in their production.Las vesículas extracelulares (VEs), exosomas y micro vesículas son un tipo de estructuras heterogéneas presentes en la mayoría de los fluidos orgánicos incluyendo el fluido oviductal. Las VEs contienen varios compuestos derivados de la célula original, como proteínas, lípidos, ARNm, miARN y ADN. Las VEs en el oviducto son producidas por las células epiteliales y entre sus funciones se encuentran: interacción con los espermatozoides, mantener la viabilidad de estos, participar en la maduración de los ovocitos y en el proceso de fecundación.
Durante la fecundación in vitro y, con el fin de mejorarla imitando las condiciones in vivo, numerosos investigadores han utilizado cultivos de células del epitelio oviductal bovino (CEOB) con notables mejoras. Estas células producen, entre otros componentes VEs, por ello, en este trabajo hemos planteado un estudio comparativo de VEs presentes en el fluido oviductal (FO) bovino recogido en momentos próximos a la ovulación (in vivo) y de aquellas VEs producidas en cultivos de CEOB a los 7 días de cultivo (in vitro) comparando el tamaño, la distribución de la población y la concentración de proteína en ambos tipos. Las VEs se identificaron mediante microscopía electrónica, su tamaño mediante dispersión de luz láser y la concentración de proteínas mediante el método Bradford.
Los resultados mostraron que el tamaño de las VEs fue similar entre ambos grupos experimentales. Por otro lado, sí que se observaron diferencias en cuanto a la concentración de proteínas. Las VEs obtenidas in vivo contenían mayor cantidad de proteína en su cargo que en las VEs obtenidas in vitro.
En cuanto a identificación de las VEs mediante microscopía electrónica de transmisión, solo pudieron ser observadas aquellas obtenidas in vivo. Este hecho podría deberse al lugar de dónde han sido recogidas, al método de cultivo de células epiteliales oviductales bovinas o la escasez en su producción
Immobilization in diabetic rats results in altered glucose tolerance A model of reduced locomotion/activity in diabetes
A Rat Immobilization Model Based on Cage Volume Reduction: A Physiological Model for Bed Rest?
Bed rest has been an established treatment in the past prescribed for critically illness or convalescing patients, in order to preserve their body metabolic resource, to prevent serious complications and to support their rapid path to recovery. However, it has been reported that prolonged bed rest can have detrimental consequences that may delay or prevent the recovery from clinical illness. In order to study disuse-induced changes in muscle and bone, as observed during prolonged bed rest in humans, an innovative new model of muscle disuse for rodents is presented. Basically, the animals are confined to a reduced space designed to restrict their locomotion movements and allow them to drink and eat easily, without generating physical stress. The animals were immobilized for either 7, 14, or 28 days. The immobilization procedure induced a significant decrease of food intake, both at 14 and 28 days of immobilization. The reduced food intake was not a consequence of a stress condition induced by the model since plasma corticosterone levels –an indicator of a stress response– were not altered following the immobilization period. The animals showed a significant decrease in soleus muscle mass, grip force and cross-sectional area (a measure of fiber size), together with a decrease in bone mineral density. The present model may potentially serve to investigate the effects of bed-rest in pathological states characterized by a catabolic condition, such as diabetes or cancer
On the relativistic precession and oscillation frequencies of test particles around rapidly rotating compact stars
Whether analytic exact vacuum(electrovacuum) solutions of the
Einstein(Einstein-Maxwell) field equations can accurately describe or not the
exterior spacetime of compact stars remains still an interesting open question
in Relativistic Astrophysics. As an attempt to establish their level of
accuracy, the radii of the Innermost Stable Circular Orbits (ISCOs) of test
particles given by analytic exterior spacetime geometries have been compared
with the ones given by numerical solutions for neutron stars (NSs) obeying a
realistic equation of state (EoS). It has been so shown that the six-parametric
solution of Pach\'on, Rueda, and Sanabria (2006) (hereafter PRS) is more
accurate to describe the NS ISCO radii than other analytic models. We propose
here an additional test of accuracy for analytic exterior geometries based on
the comparison of orbital frequencies of neutral test particles. We compute the
Keplerian, frame-dragging, as well as the precession and oscillation
frequencies of the radial and vertical motions of neutral test particles for
the Kerr and PRS geometries; then we compare them with the numerical values
obtained by Morsink and Stella (1999) for realistic NSs. We identify the role
of high-order multipole moments such as the mass quadrupole and current
octupole in the determination of the orbital frequencies especially in the
rapid rotation regime. The results of this work are relevant to cast a
separatrix between black hole (BH) and NS signatures as well as probe the
nuclear matter EoS and NS parameters from the Quasi-Periodic Oscillations
(QPOs) observed in Low Mass X-Ray Binaries.Comment: 14 pages, 10 figure
A rat immobilization model based on cage volume reduction: a physiological model for bed rest?
Bed rest has been an established treatment in the past prescribed for critically illness or convalescing patients, in order to preserve their body metabolic resource, to prevent serious complications and to support their rapid path to recovery. However, it has been reported that prolonged bed rest can have detrimental consequences that may delay or prevent the recovery from clinical illness. In order to study disuse-induced changes in muscle and bone, as observed during prolonged bed rest in humans, an innovative new model of muscle disuse for rodents is presented. Basically, the animals are confined to a reduced space designed to restrict their locomotion movements and allow them to drink and eat easily, without generating physical stress. The animals were immobilized for either 7, 14, or 28 days. The immobilization procedure induced a significant decrease of food intake, both at 14 and 28 days of immobilization. The reduced food intake was not a consequence of a stress condition induced by the model since plasma corticosterone levels-an indicator of a stress response- were not altered following the immobilization period. The animals showed a significant decrease in soleus muscle mass, grip force and cross-sectional area (a measure of fiber size), together with a decrease in bone mineral density. The present model may potentially serve to investigate the effects of bed-rest in pathological states characterized by a catabolic condition, such as diabetes or cancer
The program for biodiversity research in Brazil: The role of regional networks for biodiversity knowledge, dissemination, and conservation
The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes
J-PLUS: The javalambre photometric local universe survey
ABSTRACT: TheJavalambrePhotometric Local UniverseSurvey (J-PLUS )isanongoing 12-band photometricopticalsurvey, observingthousands of squaredegrees of theNorthernHemispherefromthededicated JAST/T80 telescope at the Observatorio Astrofísico de Javalambre (OAJ). The T80Cam is a camera with a field of view of 2 deg2 mountedon a telescopewith a diameter of 83 cm, and isequippedwith a uniquesystem of filtersspanningtheentireopticalrange (3500–10 000 Å). Thisfiltersystemis a combination of broad-, medium-, and narrow-band filters, optimallydesigned to extracttherest-framespectralfeatures (the 3700–4000 Å Balmer break region, Hδ, Ca H+K, the G band, and the Mg b and Ca triplets) that are key to characterizingstellartypes and delivering a low-resolutionphotospectrumforeach pixel of theobservedsky. With a typicaldepth of AB ∼21.25 mag per band, thisfilter set thusallowsforanunbiased and accuratecharacterization of thestellarpopulation in our Galaxy, itprovidesanunprecedented 2D photospectralinformationforall resolved galaxies in the local Universe, as well as accuratephoto-z estimates (at the δ z/(1 + z)∼0.005–0.03 precisionlevel) formoderatelybright (up to r ∼ 20 mag) extragalacticsources. Whilesomenarrow-band filters are designedforthestudy of particular emissionfeatures ([O II]/λ3727, Hα/λ6563) up to z < 0.017, theyalsoprovidewell-definedwindowsfortheanalysis of otheremissionlines at higherredshifts. As a result, J-PLUS has thepotential to contribute to a widerange of fields in Astrophysics, both in thenearbyUniverse (MilkyWaystructure, globular clusters, 2D IFU-likestudies, stellarpopulations of nearby and moderate-redshiftgalaxies, clusters of galaxies) and at highredshifts (emission-line galaxies at z ≈ 0.77, 2.2, and 4.4, quasi-stellarobjects, etc.). Withthispaper, wereleasethefirst∼1000 deg2 of J-PLUS data, containingabout 4.3 millionstars and 3.0 milliongalaxies at r < 21mag. With a goal of 8500 deg2 forthe total J-PLUS footprint, thesenumbers are expected to rise to about 35 millionstars and 24 milliongalaxiesbytheend of thesurvey.Funding for the J-PLUS Project has been provided by the Governments of Spain and Aragón through the Fondo de Inversiones de Teruel, the Spanish Ministry of Economy and Competitiveness (MINECO; under grants AYA2017-86274-P, AYA2016-77846-P, AYA2016-77237-C3-1-P, AYA2015-66211-C2-1-P, AYA2015-66211-C2-2, AYA2012-30789, AGAUR grant SGR-661/2017, and ICTS-2009-14), and European FEDER funding (FCDD10-4E-867, FCDD13-4E-2685
- …