Veins composed of glaucophane + phengite + quartz cross-cut the high pressure-low temperature (HP-LT) Cycladic Blueschist Unit (CBU) of southern Evia, Greece. The veins exhibit a rheology-dependent ...distribution within layered metamorphic rock comprising cm-scale intercalations of albite-clinopyroxene metabasalt and schistose quartzite. Strain was accommodated by ductile processes in the quartzite, whereas brittle deformation produced four sets of crack-seal syntaxial veins in the coarser-grained metabasalt. All vein sets are subvertical to steeply-dipping and are oriented at high angles to one another. The geometry of the planar vein walls suggests the veins are mode-I (opening mode) fractures, whose sub-vertical orientations indicate formation during extension. Oxygen isotope thermometry using phengite-quartz pairs provides crystallization temperatures of 315–335 °C. Combined
40
Ar/
39
Ar and
in-situ
87
Rb/
87
Sr geochronology of vein-hosted phengite and glaucophane indicate crystallization and vein sealing at
c
. 22–23 Ma when the CBU is predicted to be undergoing greenschist facies metamorphism coincident with regional extension. The structural and stable isotope data are likewise consistent with a syn-exhumation extensional setting, and easily reconciled with existing petrological data indicating the CBU sustained prolonged residence near the greenschist-blueschist facies boundary. We propose a model whereby phengite and glaucophane were stabilized at greenschist facies conditions by the elevated α
SiO2
and
f
O
2
in the fluid parental to the veins. Our data provide strong new evidence for the sensitivity of nominally blueschist facies minerals to bulk system chemistry, supported by thermodynamic modelling evidence from other orogens that such HP-LT minerals may exhibit stability that spans multiple stages of orogenesis.
The synthesis of the cyclic, naturally occurring amino acid baikiain from glycine and cis‐1,4‐butenediol is reported. The key step of the synthesis is an enantioselective phase transfer catalyzed ...allylation of the benzophenone imine of glycine t‐butyl ester, catalyzed by a cinchonidine quaternary ammonium salt, which provided the allylated glycine in 82% yield and 80% e.e. Further deprotection and hydrolysis of the Schiff base followed by an intramolecular Mitsunobu ring closure reaction yielded the corresponding piperidine ring system in 77% yield, which by hydrolysis yielded baikiain hydrochloride in 36% overall yield. Hydrogenation of the double bond could provide access to (S)‐pipecolic acid, which is also an important chiral synthon.
Synthesis of the cyclic naturally occurring amino acid baikiain from glycine and cis‐1,4‐butenediol using asymmetric phase transfer catalysis is reported in a 36% overall yield and with an 80% e.e.
•Abnormally high values of theta absolute power in older adults hamper sentence processing.•Older adults at risk of cognitive decline display brain electrical signs of syntactic difficulties.•EEG ...risk (excess theta) in older adults might be an indicator for cognitive decline.
To examine the effects of working memory (WM) load and gender agreement on sentence processing as a function of the electroencephalographic risk (i.e., abnormally high values of theta absolute power) of cognitive decline in older adults.
Event-related potentials (ERPs) were collected from Spanish speakers (22 older adults belonged to the Risk group, mean age = 67.7 years; 22 older adults belonged to the Control group, mean age = 65.2 years) while reading sentences to detect grammatical errors. Sentences varied with regard to (1) the gender agreement of the noun and adjective, where gender of the adjective either agreed or disagreed with the noun, and (2) WM load (i.e., the number of words between the noun and adjective in the sentence).
The Risk group showed a lower percentage of correct answers and longer reaction times than the Control group. The Risk group also showed a different pattern of ERP components, which was characterized by smaller amplitude and longer latency of the P600a component under high WM load conditions.
The findings suggest that the Risk group shows difficulties integrating information associated with the previous sentence context.
The electroencephalographic risk factor of cognitive decline might be not only a predictor of but also an indicator of current decline.
Immunotherapies based on antibody fragments have been developed and applied to human diseases, describing novel antibody formats. The vNAR domains have a potential therapeutic use related to their ...unique properties. This work used a non-immunized Heterodontus francisci shark library to obtain a vNAR with recognition of TGF-β isoforms. The isolated vNAR T1 selected by phage display demonstrated binding of the vNAR T1 to TGF-β isoforms (-β1, -β2, -β3) by direct ELISA assay. These results are supported by using for the first time the Single-Cycle kinetics (SCK) method for Surface plasmon resonance (SPR) analysis for a vNAR. Also, the vNAR T1 shows an equilibrium dissociation constant (K
) of 9.61 × 10
M against rhTGF-β1. Furthermore, the molecular docking analysis revealed that the vNAR T1 interacts with amino acid residues of TGF-β1, which are essential for interaction with type I and II TGF-β receptors. The vNAR T1 is the first pan-specific shark domain reported against the three hTGF-β isoforms and a potential alternative to overcome the challenges related to the modulation of TGF-β levels implicated in several human diseases such as fibrosis, cancer, and COVID-19.
Piezoelectric cement-based composites could serve to monitor the strain state of structural elements or act as self-powered materials in structural health monitoring (SHM) applications. The ...incorporation of piezoelectric materials as an active phase within cement matrices has presented a highly attractive avenue until today. However, their application is challenged by the low electrical conductivity of the hydrated cement matrix. Gold nanoparticles (Au NPs) possess substantial potential for elevating the free electrical charge within the matrix, increasing its electrical conductivity between the Au NPs and the cement matrix, thereby enhancing the piezoelectric response of the composite. In this sense, the objective of this study is to investigate the effects of incorporating low concentrations of gold nanoparticles (Au NPs) (442 and 658 ppm) on the electrical and piezoelectric properties of cement-based composites. Additionally, this study considers the effects of such properties when the material is cured under a constant electric field. Electrical impedance spectroscopy was used to evaluate the polarization resistance and piezoresistive properties of the material. Additionally, open-circuit potential measurements were taken alongside the application of mechanical loads to assess the piezoelectric activity of the composites. The findings revealed a notable decrease in the composite's total electrical resistance, reaching a value of 1.5 ± 0.2 kΩ, almost four times lower than the reference specimens. In the realm of piezoelectricity, the piezoelectric voltage parameter g33 exhibited a remarkable advancement, improving by a factor of 57 when compared to reference specimens. This significant enhancement can be attributed to both the concentration of Au NPs and the electrical curing process. In summary, the outcomes of this study underscore the feasibility of creating a highly electrically conductive cement-based matrix, using low concentrations of gold nanoparticles as electric charge carries, and indicate the possible piezoelectric behavior of the studied compposite.
To quantify the physical activity levels in dogs with cranial cruciate ligament rupture before and after lateral fabellar suture stabilisation surgery.
Seventeen dogs (mean weight, 12.3±5.1 kg) with ...unilateral cranial cruciate ligament rupture were fitted with an accelerometer for seven consecutive days at four different time points: before surgery (T0), one (T1), three (T3) and six (T6) months after surgery. The total activity and times spent in sedentary activity, light to moderate activity and vigorous activity were recorded by the accelerometer, and preoperative and postoperative data were compared. At all time points, dogs underwent clinical evaluations (lameness score, stifle pain score and thigh circumference) and their owners were asked to respond to questionnaires to subjectively score the physical activity and quality of life of the dogs.
At the four time points, the dogs spent between 21.2 and 21.4 hours on sedentary behaviour, 2.3 and 2.5 hours performing light to moderate activity, and 13 to 15 minutes performing vigorous activity. There was no increase in physical activity variables or decrease in sedentary behaviour over time. Lameness scores, pain score and dogs' quality of life improved significantly during the postoperative period. At T6, 17 (100%) of 17 dogs presented no lameness, 16 (94%) of 17 dogs presented no stifle pain, 16 (94%) of 17 owners rated the quality of life as very good and excellent, and 16 (100%) of 16 owners reported a total return to normal activity levels.
The clinical recovery after extracapsular stabilisation of the stifle joint was not associated with a spontaneous increase in physical activity or a decrease in sedentary behaviour.
The modification of medical devices is an area that has attracted a lot of attention in recent years; particularly, those developments which search to modify existing devices to render them ...antimicrobial. Most of these modifications involve at least two stages (modification of the base material with a polymer graft and immobilization of an antimicrobial agent) which are both time-consuming and complicate synthetic procedures; therefore, as an improvement, this project sought to produce antimicrobial silicone (PDMS) in a single step. Using gamma radiation as both an energy source for polymerization initiation and as a source of reducing agents in solution, PDMS was simultaneously grafted with acrylic acid and ethylene glycol dimethacrylate (AAc:EGDMA) while producing antimicrobial silver nanoparticles (AgNPs) onto the surface of the material. To obtain reproducible materials, experimental variables such as the effect of the dose, the intensity of radiation, and the concentration of the silver salt were evaluated, finding the optimal reaction conditions to obtain materials with valuable properties. The characterization of the material was performed using electronic microscopy and spectroscopic techniques such as
C-CPMAS-SS-NMR and FTIR. Finally, these materials demonstrated good antimicrobial activity against
while retaining good cell viabilities (above 90%) for fibroblasts BALB/3T3.
AbstractThe transport timescales residence time, exposure time, and age of water are evaluated for the St. Louis Bay estuary, Mississippi, to investigate the impacts of freshwater inflows and tidal ...dynamics from Mississippi Sound on the estuary’s transport characteristics. The timescales are explicitly defined and computed using a hydrodynamic model and tracer experiments for a set of 11 hydrologic scenarios designed to represent permanent low, average, and high flow conditions. Results indicate that (1) the estuary’s residence time can vary between 2.0 and 134.5 days during high and low flow conditions, respectively; (2) under low flow conditions dispersive processes caused by the tidal dynamics at the estuary’s open boundary may be dominant, and the returning flows can increase the exposure times up to 30% in relation to the residence times; (3) during high flow conditions advective transport caused by the freshwater flows may be dominant resulting in exposure times similar to the residence times; and, (4) there are important spatial variations in the estuary's flushing characteristics as evaluated by the age of water.
Social support (SS) influences the elderly ability to cope with the losses of ageing process. This study was aimed at assessing SS among elderly users of a primary healthcare unit in a poor and ...violent area of Rio de Janeiro City, and at verifying its association with depression, self-perceived health (SPH), marital status and chronic illnesses.
A cross-sectional study was performed based on a convenience sample of 180 individuals aged 60 years or older. SS was measured with part of the Brazilian version of Medical Outcomes Study's SS scale, and SPH and depression were assessed, respectively, through one question and the Brazilian version of the Structured Clinical Interview for DSM-IV Axis I Disorders. SS medians were calculated for the categories of SPH, depression, marital status and chronic illnesses variables, and differences were evaluated with the Kruskal-Wallis and Mann-Whitney tests. Additionally, Pearson's chi-square test and logistic regression were employed to identify unadjusted and adjusted associations between SS and those variables.
The participant's mean age was 73 years old, and level of education was 3 years of school education on average. They were predominantly females (73.3%), and non-married (55.0%). Among them, 74.4% perceived their SS as satisfactory, 55.0% perceived their health as good, 27.8% were diagnosed with major depression and 83.3% had hypertension. Especially for those depressed and with bad SPH, the medians of SS measure were much lower than for others, reaching an unsatisfactory level. Moreover, controlling for other factors, non-depressed individuals were more likely (OR = 2.32) to have satisfactory SS.
in the violent and poor area explored in this research low SS is highly prevalent in the elderly. Depressed individuals are more likely to have low SS and this condition should be investigated in depressed elderly. The reduced scale is useful for low education individuals.
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