264 research outputs found
Inverse Orbital Torque via Spin-Orbital Entangled States
While current-induced torque by orbital current has been experimentally found
in various structures, evidence for its reciprocity has been missing so far.
Here, we report experimental evidences of strong inverse orbital torque in
YIG/Pt/CuOx (YIG = Y3Fe5O12) mediated by spin-orbital entangled electronic
states in Pt. By injecting spin current from YIG to Pt by the spin pumping via
ferromagnetic resonance and by the spin Seebeck effect, we find a pronounced
inverse spin Hall effect-like signal. While a part of the signal is explained
as due to the inverse spin-orbital Hall effect in Pt, we also find substantial
increase of the signal in YIG/Pt/CuOx structures compared to the signal in
YIG/Pt. We attribute this to the inverse orbital Edelstein effect at Pt/CuOx
interface mediated by the spin-orbital entangled states in Pt. Our work paves
the way toward understanding of spin-orbital entangled physics in
nonequilibrium and provides a way for electrical detection of the orbital
current in orbitronic device applications.Comment: 8 pages, four figure
Exploring orbital-charge conversion mediated by interfaces with copper through spin-orbital pumping
We investigated how different materials affect the orbital-charge conversion
in heterostructures with the naturally oxidized cooper capping layer. When we
added a thin layer of onto yttrium iron garnet stacks, we
observed a significant reduction in the charge current signal measured by means
the spin pumping effect technique. This finding contrasts with the results of a
prior study conducted on YIG/Pt/CuOx, which reported the opposite effect. On
the other hand, when we added the same layer to
structures, there was not much change in the spin pumping signal. This occurred
because Ti does not generate much orbital current at the interface,
unlike Pt, due to its weaker spin-orbit coupling. Interestingly, when we added
the layer to structures, the spin pumping
signal increased. However, in structures,
the signal decreased. Finally, we delve into a theoretical analysis of the spin
(orbital) Hall effect in YIG/Heavy-metal systems. These findings have the
potential to advance research in the innovative field of orbitronics and
contribute to the development of new technologies based on spin-orbital
conversion.Comment: 21 pages, 6 figures
Surface-state mediated spin-to-charge conversion in Sb films via bilateral spin current injection
The spin-to-charge conversion phenomena is investigated in a trilayer
structure consisting of Co(12 nm)/Sb(t)/Py(12 nm), where the thickness t of the
antimony layer is varied. Using the spin-pumping technique, a pure spin current
is injected from both FM layers into the middle layer, the DC voltage is then
measured. We observe a spin-to-charge mechanism in the Sb layer that exhibits
striking similarities to the inverse Rashba-Edelstein effect (IREE), driven by
surface states.Comment: 6 pages, 4 figure
Produção de fitoalexinas e suscetibilidade de diversos genótipos de soja ao tamanduá-da-soja Sternechus subsignatus em casa de vegetação.
Encrypted antimicrobial peptides from plant proteins.
Abstract Examples of bioactive peptides derived from internal sequences of proteins are known for decades. The great majority of these findings appear to be fortuitous rather than the result of a deliberate and methodological-based enterprise. In the present work, we describe the identification and the biological activities of novel antimicrobial peptides unveiled as internal fragments of various plant proteins founded on our hypothesis-driven search strategy. All putative encrypted antimicrobial peptides were selected based upon their physicochemical properties that were iteratively selected by an in-house computer program named Kamal. The selected peptides were chemically synthesized and evaluated for their interaction with model membranes. Sixteen of these peptides showed antimicrobial activity against human and/or plant pathogens, some with a wide spectrum of activity presenting similar or superior inhibition efficacy when compared to classical antimicrobial peptides (AMPs). These original and previously unforeseen molecules constitute a broader and undisputable set of evidences produced by our group that illustrate how the intragenic concept is a workable reality and should be carefully explored not only for microbicidal agents but also for many other biological functions
Estudos preliminares relacionados ao metabolismo de resistência e tolerância à ferrugem asiática da soja.
Intragenic antimicrobial peptides (IAPs) from human proteins with potent antimicrobial and anti-inflammatory activity
Following the treads of our previous works on the unveiling of bioactive peptides encrypted
in plant proteins from diverse species, the present manuscript reports the occurrence of four
proof-of-concept intragenic antimicrobial peptides in human proteins, named Hs IAPs.
These IAPs were prospected using the software Kamal, synthesized by solid phase chemistry,
and had their interactions with model phospholipid vesicles investigated by differential
scanning calorimetry and circular dichroism. Their antimicrobial activity against bacteria,
yeasts and filamentous fungi was determined, along with their cytotoxicity towards erythrocytes.
Our data demonstrates that Hs IAPs are capable to bind model membranes while
attaining α-helical structure, and to inhibit the growth of microorganisms at concentrations
as low as 1μM. Hs02, a novel sixteen residue long internal peptide (KWAVRIIRKFIKGFISNH2)
derived from the unconventional myosin 1h protein, was further investigated in its
capacity to inhibit lipopolysaccharide-induced release of TNF-α in murine macrophages.
Hs02 presented potent anti-inflammatory activity, inhibiting the release of TNF-α in LPSprimed
cells at the lowest assayed concentration, 0.1 μM. A three-dimensional solution
structure of Hs02 bound to DPC micelles was determined by Nuclear Magnetic Resonance.
Our work exemplifies how the human genome can be mined for molecules with biotechnological
potential in human health and demonstrates that IAPs are actual alternatives to antimicrobial
peptides as pharmaceutical agents or in their many other putative applications
Pilot, randomized, placebo-controlled clinical field study to evaluate the effectiveness of bupivacaine liposome injectable suspension for the provision of post-surgical analgesia in dogs undergoing stifle surgery
Abstract Background Local anesthetics are an important component of perioperative pain management, but the duration of action of available products is limited. We hypothesized that a single local infiltration of a novel bupivacaine liposome injectable suspension (AT-003) would provide clinically effective analgesia over a 72-h period. In a masked, randomized, placebo-controlled, multi-center pilot field study, dogs undergoing lateral retinacular suture placement for cranial cruciate insufficiency were randomly assigned to surgical site infiltration with AT-003 (5.3 mg/kg) or an equivalent volume of saline. Infiltration of the surgical site was done prior to closure. Primary outcome measure was the Glasgow Composite Measure Pain Scale (CMPS-SF) assessed prior to surgery and at 2, 4, 8, 12, 24, 30, 36, 48, 54, 60 and 72 h following surgery by trained individuals. Provision for rescue analgesia was employed. Repeated measures analysis of variance were utilized to test for possible differences between treatment groups and a success/failure analysis was also employed, based on the need for rescue analgesia. Results Forty-six dogs were enrolled and evaluated. For CMPS-SF scores there was a significant overall treatment effect (p = 0.0027) in favor of AT-003. There were significantly more successes in the AT-003 group compared to placebo over each time period (p = 0.0001 for 0–24 h, p = 0.0349 for 0–48 h, and p = 0.0240 for 0-72 h). No significant adverse events were seen. Conclusions AT-003 (bupivacaine liposome injectable suspension) provided measurable local analgesia over a 72-h period following post-stifle surgery surgical site tissue infiltration. Further work is indicated to develop this product for clinical use
Study of the number of occlusal contacts in maximum intercuspation before orthodontic treatment in subjects with Angle Class I and Class II Division 1 malocclusion
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