4,482 research outputs found
Editorial: The Natural Killer Cell Interactome in the Tumor Microenvironment: Basic Concepts and Clinical Application
NK cell activity is impaired in cancer patients, supporting the use of adoptive NK cell therapy, which is becoming a credible immunotherapy for hematological malignancies. This is even more so the case after the presentation of the first clinical study using anti-CD19 NK CAR cells, which showed a good clinical activity in the absence of toxicity. The possibility of targeting solid tumors is being studied by numerous laboratories, but the tumor microenvironment supports immune suppression. Unveiling the molecular and cellular mechanisms explaining this immunosuppression is a major goal.
For this special issue, we pointed to several specific subjects, such as the metabolic interactions of NK cells with tumor targets that would regulate their function or novel molecular strategies for generating off-the-shelf NK cell cancer immunotherapies. A total of 10 manuscripts have been accepted for publication, of which five are original research and five are reviews or minireviews. Regarding the original research articles, Alvarez et al. have described the indirect contribution of the PD-1/PD-L1 system to the regulation of NK cell exhaustion using an in vivo murine model. They showed that a PD-1 blockade increased CD8+ T cell activation rates, which competed for IL-2 and resources with NK cells, retarding their activation but also their subsequent exhaustion. Federici et al. developed an exhaustive work characterizing NK-cell derived extracellular vesicles (NKEVs), separating true exosomes from microvesicles..
Use of Unpalatable Forages by Ruminants: The Influence of Experience with the Biophysical and Social Environment
Unpalatable forage resources (low nutrient density, potentially toxic metabolites) are widespread and represent a challenge for ruminant nutrition, health, and welfare. Our objective was to synthesize the role of biophysical and social experience on the use of unpalatable forages by ruminants, and highlight derived behavioural solutions for the well-being of soils, plants, and animals. Environmental experiences early in life modulate gene expression and promote learning, which alters morpho-physiological and psychological mechanisms that modify behavioural responses and change food and habitat selection. In this process, ruminants can become better adapted to the habitat where they are reared. Moreover, experiential learning provides flexibility in diet selection, which is critical for changing foraging environments. Learned associations between unpalatable and palatable foods, if ingested in appropriate amounts, sequence, and close temporal association, induce the development of preference for the former type of food. In this way, a more uniform use of resources can be achieved from the landscape level down to the individual plant, with the associated benefits to ecosystem integrity and stability. Ruminants can also learn the medicinal benefits of ingesting foods with toxins (e.g., condensed tannins and saponins with antiparasitic properties). This knowledge on behavioural processes can be translated into behavioural applications that provide low-cost solutions to many challenges that producers face in managing sustainable livestock production systems
Spectrum of the Relativistic Particles in Various Potentials
We extend the notion of Dirac oscillator in two dimensions, to construct a
set of potentials. These potentials becomes exactly and quasi-exactly solvable
potentials of non-relativistic quantum mechanics when they are transformed into
a Schr\"{o}dinger-like equation. For the exactly solvable potentials,
eigenvalues are calculated and eigenfunctions are given by confluent
hypergeometric functions. It is shown that, our formulation also leads to the
study of those potentials in the framework of the supersymmetric quantum
mechanics
TropicalâNorth Pacific Climate Linkages over the Past Four Centuries
Analyses of instrumental data demonstrate robust linkages between decadal-scale North Pacific and tropical Indo-Pacific climatic variability. These linkages encompass common regime shifts, including the noteworthy 1976 transition in Pacific climate. However, information on Pacific decadal variability and the tropical high-latitude climate connection is limited prior to the twentieth century. Herein tree-ring analysis is employed to extend the understanding of North Pacific climatic variability and related tropical linkages over the past four centuries. To this end, a tree-ring reconstruction of the December-May North Pacific index (NPI)-an index of the atmospheric circulation related to the Aleutian low pressure cell-is presented (1600-1983). The NPI reconstruction shows evidence for the three regime shifts seen in the instrumental NPI data, and for seven events in prior centuries. It correlates significantly with both instrumental tropical climate indices and a coral-based reconstruction of an optimal tropical Indo-Pacific climate index, supporting evidence for a tropical-North Pacific link extending as far west as the western Indian Ocean. The coral-based reconstruction (1781-1993) shows the twentieth-century regime shifts evident in the instrumental NPI and instrumental tropical Indo-Pacific climate index, and three previous shifts. Changes in the strength of correlation between the reconstructions over time, and the different identified shifts in both series prior to the twentieth century, suggest a varying tropical influence on North Pacific climate, with greater influence in the twentieth century. One likely mechanism is the low-frequency variability of the El Nino-Southern Oscillation (ENSO) and its varying impact on Indo-Pacific climate.</p
Influence of Gravity on noncommutative Dirac equation
In this paper, we investigate the influence of gravity and noncommutativity
on Dirac equation. By adopting the tetrad formalism, we show that the modified
Dirac equation keeps the same form. The only modification is in the expression
of the covariant derivative. The new form of this derivative is the product of
its counterpart given in curved space-time with an operator which depends on
the noncommutative -parameter. As an application, we have computed the
density number of the created particles in presence of constant strong electric
field in an anisotropic Bianchi universe.Comment: 9 pages, correct some miprints, Accepted for publication in journal
of Mod. Phys. Letters
Two electron entanglement enhancement by an inelastic scattering process
In order to assess inelastic effects on two fermion entanglement production,
we address an exactly solvable two-particle scattering problem where the target
is an excitable scatterer. Useful entanglement, as measured by the two particle
concurrence, is obtained from post-selection of oppositely scattered particle
states. The matrix formalism is generalized in order to address non-unitary
evolution in the propagating channels. We find the striking result that
inelasticity can actually increase concurrence as compared to the elastic case
by increasing the uncertainty of the single particle subspace. Concurrence
zeros are controlled by either single particle resonance energies or total
reflection conditions that ascertain precisely one of the electron states.
Concurrence minima also occur and are controlled by entangled resonance
situations were the electron becomes entangled with the scatterer, and thus
does not give up full information of its state. In this model, exciting the
scatterer can never fully destroy phase coherence due to an intrinsic limit to
the probability of inelastic events.Comment: 8 pages, to appear in Phys. Rev
Environmental and Animal Benefits when Beef Cattle Consume Condensed and Hydrolysable Tannins
This fact sheet describes the environmental and animal benefits when cattle consume condensed and hydrolysable tannins, and includes producer concerns
Bound states of scalar particles in the presence of a short range potential
We analyze the behavior of the energy spectrum of the Klein-Gordon equation
in the presence of a truncated hyperbolic tangent potential. From our analysis
we obtain that, for some values of the potential there is embedding of the
bound states into the negative energy continuum, showing that, in opposition to
the general belief, relativistic scalar particles in one-dimensional short
range potentials can exhibit resonant behavior and not only the Schiff-Snyder
effect.Comment: To appear in Modern Physics Letters
Scattering of a Klein-Gordon particle by a Woods-Saxon potential
We solve the Klein-Gordon equation in the presence of a spatially
one-dimensional Woods-Saxon potential. The scattering solutions are obtained in
terms of hypergeometric functions and the condition for the existence of
transmission resonances is derived. It is shown how the zero-reflection
condition depends on the shape of the potential.Comment: 10 pages, Revtex. To appear in Phys. Rev.
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