It is unclear why the severity of influenza varies in healthy adults or why the burden of severe influenza shifts to young adults when pandemic strains emerge. One possibility is that ...cross-protective T cell responses wane in this age group in the absence of recent infection. We therefore compared the acute cellular immune response in previously healthy adults with severe versus mild pandemic H1N1 infection.
49 previously healthy adults admitted to the National Hospital of Tropical Diseases, Viet Nam with RT-PCR-confirmed 2009 H1N1 infection were prospectively enrolled. 39 recovered quickly whereas 10 developed severe symptoms requiring supplemental oxygen and prolonged hospitalization. Peripheral blood lymphocyte subset counts and activation (HLADR, CD38) and differentiation (CD27, CD28) marker expression were determined on days 0, 2, 5, 10, 14 and 28 by flow cytometry. NK, CD4 and CD8 lymphopenia developed in 100%, 90% and 60% of severe cases versus 13% (p<0.001), 28%, (p = 0.001) and 18% (p = 0.014) of mild cases. CD4 and NK counts normalized following recovery. B cell counts were not significantly associated with severity. CD8 activation peaked 6-8 days after mild influenza onset, when 13% (6-22%) were HLADR+CD38+, and was accompanied by a significant loss of resting/CD27+CD28+ cells without accumulation of CD27+CD28- or CD27-CD28- cells. In severe influenza CD8 activation peaked more than 9 days post-onset, and/or was excessive (30-90% HLADR+CD38+) in association with accumulation of CD27+CD28- cells and maintenance of CD8 counts.
Severe influenza is associated with transient T and NK cell deficiency. CD8 phenotype changes during mild influenza are consistent with a rapidly resolving memory response whereas in severe influenza activation is either delayed or excessive, and partially differentiated cells accumulate within blood indicating that recruitment of effector cells to the lung could be impaired.
Kurz is widely used in folk medicine in Eastern Asia and is associated with various ethnopharmacological properties including hepatoprotective, antipyretic, analgesic, antidysenteric, and ...anthelmintic activities. Previous phytochemical investigations reported the presence of numerous triterpenes (mostly cycloartanes, ursanes, lupanes, and oleananes) along with dozens of flavonoids. However, the extracts of
and isolated flavonoids have not been evaluated for their alpha-glucosidase inhibition. In the frame of our efforts dedicated to the chemical investigation of Vietnamese medicinal plants and their biological activities, a phytochemical study of the MeOH extract of the leaves of
using bioactive guided isolation was undertaken. In this paper, the isolation and structure elucidation of twelve known compounds, 5-hydroxy-3,7,4'-trimethoxyflavone (
), ayanin (
), kumatakenin (
), rhamnocitrin (
), ombuin (
), myricetin-3,7,3',5'-tetramethyl ether (
), gardenin D (
), luteolin (
), apigenin (
), mearnsetin (
), isoorientin (
), and vitexin (
) were reported. Bromination was applied to compounds
and
to provide four new synthetic analogues
-
. All isolated and synthesized compounds were evaluated for alpha-glucosidase inhibition and antibacterial activity. Compounds
and
showed moderate antibacterial activity against methicillin-resistant
while others were inactive. All compounds failed to reveal any activity toward extended spectrum beta-lactamase-producing
. Compounds
,
,
-
, and
-
showed good alpha-glucosidase inhibition with IC
values in the range of 30.5-282.0 µM. The kinetic of enzyme inhibition showed that
and
were noncompetitive type inhibition against alpha-glucosidase. In silico molecular docking model indicated that compounds
and
were potential inhibitors against enzyme
-glucosidase.
Multilayer neural networks are among the most powerful models in machine learning, yet the fundamental reasons for this success defy mathematical understanding. Learning a neural network requires ...optimizing a nonconvex high-dimensional objective (risk function), a problem that is usually attacked using stochastic gradient descent (SGD). Does SGD converge to a global optimum of the risk or only to a local optimum? In the former case, does this happen because local minima are absent or because SGD some-how avoids them? In the latter, why do local minima reached by SGD have good generalization properties? In this paper, we consider a simple case, namely two-layer neural networks, and prove that—in a suitable scaling limit—SGD dynamics is captured by a certain nonlinear partial differential equation (PDE) that we call distributional dynamics (DD). We then consider several specific examples and show how DD can be used to prove convergence of SGD to networks with nearly ideal generalization error. This description allows for “averaging out” some of the complexities of the landscape of neural networks and can be used to prove a general convergence result for noisy SGD.
Drug delivery to central nervous system (CNS) diseases is very challenging since the presence of the innate blood–brain barrier (BBB) and the blood-cerebrospinal fluid barrier that impede drug ...delivery. Among new strategies to overcome these limitations and successfully deliver drugs to the CNS, nanotechnology-based drug delivery platform, offers potential therapeutic approach for the treatment of some common neurological disorders like Alzheimer’s disease, frontotemporal dementia, amyotrophic lateral sclerosis, Parkinson’s disease, Huntington’s disease. This review aimed to highlight advances in research on the development of nano-based therapeutics for their implications in therapy of CNS disorders. The challenges during clinical translation of nanomedicine from bench to bed side is also discussed.
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•Summarize current strategies and new trends of CNS drug.•Emphasis on nanotechnology-based drug delivery systems for CNS management.•Advantages of the nanomedicine therapeutics.•Current trends and challenges in the clinical translation of nanomedicine for CNS disorders.
Intravoxel incoherent motion (IVIM) imaging concurrently measures diffusion and perfusion parameters and has potential applications for brain tumor classification. However, the effectiveness of IVIM ...for the differentiation between pilocytic astrocytoma and ependymoma has not been verified. The aim of this study was to determine the potential diagnostic role of IVIM for the distinction between ependymoma and pilocytic astrocytoma.
Between February 2019 and October 2020, 22 children (15 males and 7 females; median age 4 years) with either ependymoma or pilocytic astrocytoma were recruited for this prospective study. IVIM parameters were fitted using 7 b-values (0-1,500 s/mm2), to develop a bi-exponential model. The diffusivity (D), perfusion fraction (f), and pseudo diffusivity (D*) were measured in both tumors and the adjacent normal-appearing parenchyma. These IVIM parameters were compared using the Mann-Whitney U test. Receiver operating characteristic (ROC) curve analysis was employed to assess diagnostic performance.
The median D values for ependymoma and pilocytic astrocytoma were 0.87 and 1.25 × 10-3 mm2/s (p < 0.05), respectively, whereas the f values were 0.11% and 0.15% (p < 0.05). The ratios of the median D values for ependymoma and pilocytic astrocytoma relative to the median D values for the adjacent, normal-appearing parenchyma were 1.45 and 2.10 (p < 0.05), respectively. ROC curve analysis found that the D value had the best diagnostic performance for the differentiation between pilocytic astrocytoma and ependymoma, with an area under the ROC curve of 1.
IVIM is a beneficial, effective, non-invasive, and endogenous-contrast imaging technique. The D value derived from IVIM was the most essential factor for differentiating ependymoma from pilocytic astrocytoma.
Summary
We propose a surrogate model for two‐scale computational homogenization of elastostatics at finite strains. The macroscopic constitutive law is made numerically available via an explicit ...formulation of the associated macroenergy density. This energy density is constructed by using a neural network architecture that mimics a high‐dimensional model representation. The database for training this network is assembled through solving a set of microscopic boundary value problems with the prescribed macroscopic deformation gradients (input data) and subsequently retrieving the corresponding averaged energies (output data). Therefore, the two‐scale computational procedure for nonlinear elasticity can be broken down into two solvers for microscopic and macroscopic equilibrium equations that work separately in two stages, called the offline and online stages. The finite element method is employed to solve the equilibrium equation at the macroscale. As for microscopic problems, an FFT‐based collocation method is applied in tandem with the Newton‐Raphson iteration and the conjugate‐gradient method. Particularly, we solve the microscopic equilibrium equation in the Lippmann‐Schwinger form without resorting to the reference medium. In this manner, the fixed‐point iteration that might require quite strict numerical stability conditions in the nonlinear regime is avoided. In addition, we derive the projection operator used in the FFT‐based method for homogenization of elasticity at finite strain.
•Ag/rGO was successfully synthesized by co-precipitation.•L-ascorbic acid (environmentally friendly and abundant) was used as the reducing agent.•AgNPs with size 16 ± 3.7 nm were decorated on ...rGO.•Amount of reducing agents and catalysts, reaction time and type of dye significantly affect the antibacterial activity.•Ag/rGO effectively inhibited the development of Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa.
The present study involved the preparation of silver-reduced graphene oxide (Ag/rGO) using co-precipitation method. The characteristics of Ag/rGO were confirmed by X-ray Diffraction patterns, Fourier transformation infrared spectroscopy, Raman spectroscopy, transmission electron microscopy, Brunauer–Emmett–Teller specific surface area, scanning electron microscopy, and energy-dispersive spectroscopy. The results demonstrated that silver nanoparticles (AgNPs) having diameter of 16 ± 3.7 nm were uniformly integrated on reduced graphene oxide (rGO) The as-synthesized Ag/rGO had a specific area of 54m2/g and 67.36 wt% silver. Antibacterial and catalytic properties of Ag/rGO were then further investigated. Ag/rGO was found to effectively inhibit the developing of gram-negative and gram-positive bacteria such as Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa with the bactericidal rates of 89.35, 95.67, and 99.99 %, respectively. In addition, the catalytic property of Ag/rGO in the reduction of organic dyes was tested with different dosage of reducing agent, amount of catalyst, type of dye, and reaction time. More than 99 % of dyes in aqueous solution at 20 mg/L concentration were reduced after 30 min with amounts of Ag/rGO and sodium borohydride of 10 and 30 mg successively. All results confirmed the potential application of Ag/rGO in the treatment of infected water and dye contamination.
A
bstract
We consider the strong dynamics associated with a composite Higgs model that simultaneously produces dynamical axions and solves the strong CP problem. The strong dynamics arises from a new ...Sp or SU(4) hypercolor gauge group containing QCD colored hyperfermions that confines at a high scale. The hypercolor global symmetry is weakly gauged by the Standard Model electroweak gauge group and an enlarged color group, SU(
N
+ 3)
×
SU(
N
)
′
. When hyperfermion condensates form, they not only lead to an SU(5)/SO(5) composite Higgs model but also spontaneously break the enlarged color group to SU(3)
c
×
SU(
N
)
D
. At lower energies, the SU(
N
)
D
group confines, producing two dynamical axions that eliminates all CP violation. Furthermore, small instantons from the SU(
N
)
′
group can enhance the axion mass, giving rise to TeV scale axion masses that can be detected at collider experiments. Our model provides a way to unify the composite Higgs with dynamical axions, without introducing new elementary scalar fields, while also extending the range of axion masses that addresses the strong CP problem.
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•Successfully doped Cu into ZnO lattice to enhance its photocatalytic activity.•Cu dopant prevented recombination of photo-excited e− and h+ of the ZnO.•The Cu-ZnO exhibited excellent ...photocatalytic degradation of monocrotophos pesticide.•The optimal mole ratio of Cu/ZnO in the Cu-ZnO for degradation of monocrotophos was 3%.•The optimal pH for the photocatalytic degradation of monocrotophos was pH 7.
In the work, we successfully synthesized Cu doped ZnO materials for photocatalytic degradation of monocrotophos pesticide (MCP). The used Cu metal doped into the ZnO matrix created an intermediate band to excite electron from valence band (VB) to conduction band (CD) of the ZnO leading to increase in optical absorption, decrease in band gap as well as photocatalytic performance of the material. Hence, the synthesized photocatalyst showed intense activity for photocatalytic degradation of MCP into CO2, H2O and harmless inorganic ions even under visible radiation. We also investigated that the 3Cu-ZnO photocatalyst, which the weight ratio of Cu/ZnO was 3 wt%, showed the highest MCP degradation efficiency among these synthesized Cu-ZnO. The excess dopants tended to form CuO existing on ZnO surface. The formed CuO acted as a center for recombination of produced electrons and holes resulted in decrease in photocatalytic performance of the Cu-ZnO. Finally, we investigated that the optimal pH for the degradation of MCP by the synthesized Cu doped ZnO photocatalyst was pH 7.
In the study, we used two conducting polymers, polyaniline (PANI) and polypyrrole (PPy), to sensitize Ta3N5, thereby enhancing its photocatalytic activity, and then applied this novel photocatalyst ...to overall water splitting to produce hydrogen and oxygen even under visible light irradiation. The two polymers increased the charge transfer efficiency, prevented the recombination of the generated electrons and holes of the Ta3N5 photocatalyst, and thereby enhanced its electron-hole separation efficiency and improved its photocatalytic activity for efficient visible light water splitting. The two polymers completely covering the Ta3N5 particles facilitated charge transfer for quick migration of the generated electrons and holes to the polymer surface and thus prevented contact between the holes and nitride of Ta3N5. Therefore, these conducting polymers also protected the Ta3N5 particles from self-photocorrosion during long-term water splitting. Because of the existence of the protonated nitrogen (-N+) state in PPy, the electric conductivity of PPy was lower than that of PANI, which lowered the sensitizing ability of PPy compared to that of PANI. Thus, the water splitting efficiency of Ta3N5/PANI was higher than that of Ta3N5/PPy. The production rates of H2 and O2 generated from water splitting of Ta3N5/PANI were 60.5 and 30.2 (μmol. g−1cat. h−1), respectively.
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•Polymer sensitizers enhanced the separation of e−/h+ pairs and prolonged the Ta3N5 lifetime.•Polymer cover protected Ta3N5 from self-photocorrosion (oxidation of generated holes).•Ta3N5/polymers greatly exhibited overall photocatalytic water splitting.•Lower electric conductivity lowered the sensitizing ability of the polymer.•PANI was better than PPy for enhancing the photocatalytic activity of Ta3N5.
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