Polypropylene/poly(ethylene terephthalate) blends containing montmorillonite (MMT) were prepared using a twin screw extruder followed by injection molding. The MMT dispersion was evaluated by X-ray ...diffraction and transmission electron microscopy. The results showed a better dispersion of the MMT when maleic anhydride grafted polypropylene (PP-MA) was used. The clay was preferentially situated in the PP/PET interphase and in the PET phase. The effect of the addition of the PP-MA and MMT on the morphology and mechanical properties was also evaluated. Scanning electron microscopy revealed the presence of elongated PET domains and fibers, besides the spherical shapes. The mechanical properties were studied through tensile and impact tests. The yield stress, Young modulus, and elongation at break increased when MMT and PP-MA were used without impair the impact strength. The dynamic mechanical properties were also evaluated. Higher
E′ values were observed for PP/PET/PP-MA/MMT, and a shoulder in the
E′′ curve, in intermediate
T
g’s of the pristine polymers, suggests the formation of an interphase between the two polymer domains.
Nutritional qualities of cocoa have been acknowledged by several authors; a particular focus has been placed on its high content of flavanols, known for their excellent antioxidant properties and ...subsequent protective effect on cardio- and cerebrovascular systems as well as for neuromodulatory and neuroprotective actions. Other active components of cocoa are methylxanthines (caffeine and theobromine). Whereas the effects of caffeine are extensively researched, the same is not the case for theobromine; this review summarizes evidence on the effect of theobromine on cognitive functions. Considering animal studies, it can be asserted that acute exposition to theobromine has a reduced and delayed nootropic effect with respect to caffeine, whereas both animal and human studies suggested a potential neuroprotective action of long-term assumption of theobromine through a reduction of Aβ amyloid pathology, which is commonly observed in Alzheimer’s disease patients’ brains. Hence, the conceivable action of theobromine alone and associated with caffeine or other cocoa constituents on cognitive modulation is yet underexplored and future studies are needed to shed light on this promising molecule.
PET nanocomposites were prepared using montmorillonite with different organic modifiers (Cloisite
® 15A, 30B and 10A). TEM, WAXD and DSC were used for the characterization. Nanocomposites of ...intercalated and exfoliated morphologies were obtained, and an average maximum distance between the platelets was observed in the intercalated morphology. The clay nucleated the PET crystallization process, and the nucleating effect was higher when Cloisite 10A was used. This study allowed the evaluation of the characteristics of the organic modifiers' influence on the intercalation and exfoliation processes in PET. Tactoids were obtained when only apolar modifiers were present. It was observed that PET nanocomposites were intercalated and exfoliated when polar modifiers were present.
To be able to achieve their physics goals, future neutrino-oscillation experiments will need to reconstruct the neutrino energy with very high accuracy. In this work, we analyze how the energy ...reconstruction may be affected by realistic detection capabilities, such as energy resolutions, efficiencies, and thresholds. This allows us to estimate how well the detector performance needs to be determined a priori in order to avoid a sizable bias in the measurement of the relevant oscillation parameters. We compare the kinematic and calorimetric methods of energy reconstruction in the context of two νμ → νμ disappearance experiments operating in different energy regimes. For the calorimetric reconstruction method, we find that the detector performance has to be estimated with an O(10%) accuracy to avoid a significant bias in the extracted oscillation parameters. Thus, in the case of kinematic energy reconstruction, we observe that the results exhibit less sensitivity to an overestimation of the detector capabilities.
Neutrinos were assumed to be massless particles until the discovery of the neutrino oscillation process. This phenomenon indicates that the neutrinos have non-zero masses and the mass eigenstates ...(ν1, ν2, ν3) are mixtures of their flavour eigenstates (νe, νμ, ντ). The oscillations between different flavour eigenstates are described by three mixing angles (θ12, θ23, θ13), two differences of the squared neutrino masses of the ν2/ν1 and ν3/ν1 pairs and a charge conjugation parity symmetry violating phase δCP. The Double Chooz experiment, located near the Chooz Electricité de France reactors, measures the oscillation parameter θ13 using reactor neutrinos. Here, the Double Chooz collaboration reports the measurement of the mixing angle θ13 with the new total neutron capture detection technique from the full data set, yielding sin2(2θ13) = 0.105 ± 0.014. This measurement exploits the multidetector configuration, the isoflux baseline and data recorded when the reactors were switched off. In addition to the neutrino mixing angle measurement, Double Chooz provides a precise measurement of the reactor neutrino flux, given by the mean cross-section per fission 〈σf〉 = (5.71 ± 0.06) × 10−43 cm2 per fission, and reports an empirical model of the distortion in the reactor neutrino spectrum.The Double Chooz collaboration reports the neutrino oscillation parameter θ13 from a measurement of the disappearance of reactor anti-electron neutrinos with the total neutron capture technique.
In the next generation of long-baseline neutrino oscillation experiments aiming to determine the charge-parity-violating phase δCP in the appearance channel, fine-grained time-projection chambers are ...expected to play an important role. In this study, we analyze an influence of realistic detector capabilities on the δCP sensitivity for a setup similar to that of the Deep Underground Neutrino Experiment. We find that the effect of the missing energy carried out by undetected particles is sizable. Although the reconstructed neutrino energy can be corrected for the missing energy, the accuracy of such procedure has to exceed 20%, to avoid a sizable bias in the extracted δCP value.
Background
Progressive myelomalacia (PMM) is a catastrophic disease associated with acute intervertebral disc extrusion (IVDE). Published data on the clinical characteristics of this disease are ...limited.
Objective
To describe the onset and progression of clinical signs of PMM in a large case cohort.
Animals
Fifty‐one dogs, 18 with histopathologically confirmed PMM, 33 presumptively diagnosed based on clinical signs and diagnostic imaging.
Methods
Retrospective study. Dogs with confirmed IVDE and either a histopathologic diagnosis of PMM or a high clinical suspicion were identified by medical record search. Data on nature and progression of signs were extracted.
Results
Twenty‐four of 51 dogs were Dachshunds. T12–T13 was the most common site of disc extrusion (12 of 56), and 18 of 55 of mid‐to‐caudal lumbar discs (between L3 and L6) were affected. Onset of PMM signs ranged from present at first evaluation (17/51) to 5 days after presentation, with 25 of 51 cases developing signs within 48 hours. Progression of signs from onset of PMM to euthanasia or death, excluding 7 cases euthanized at presentation, ranged from 1 to 13 days with 23 being euthanized within 3 days. Nonspecific systemic signs were documented in 30 of 51 dogs.
Conclusion and Clinical Importance
The majority of dogs developed PMM within 2 days of presentation and was euthanized within another 3 days. However, onset can be delayed up to 5 days after presentation with progression to euthanasia taking as long as 2 weeks. Mid‐to‐caudal lumbar discs might be associated with an increased risk of PMM.
The authors report their experience regarding parotidectomy performed under a three-dimensional-high-definition (3D-HD) exoscope, with the aim of evaluating its effectiveness in parotid surgery. This ...is a prospective study on nine patients treated by the same surgeon. All patients underwent parotidectomy for extrafacial primary tumours without preoperative involvement of the skin or of the facial nerve from March 2019 to June 2019 with the use of a 3D-HD exoscope. Magnification was variable from 8x to 30x with direct vision supplied by a 3D monitor. Six men and three women, mean (range) age 47.8 (19-74) years underwent parotidectomy. No patient experienced postoperative complications or definitive facial palsy. The mean (range) time of surgery was 149.4 (115 - 210) minutes. The 3D exoscope represents a valid alternative to the operative microscope or surgical loupe for parotid surgery. It is a light instrument allowing for precise surgical dissection of the parotid region by reducing the risks for iatrogenic lesions of the facial nerve using a real 3D magnification of the anatomical structures in HD. Furthermore, its use does not prolong the operative time and shows high potential for training and educational purposes since the operating room staff can better perceive the procedure and the surgeon’s fine gestures. Although the preliminary applications show promising results, there is still a need for wider scientific validation.
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