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This study investigated the adsorption properties of graphene oxide in a magnetic-assisted adsorber for the depollution of water containing heavy metals. Two samples of graphene oxide with different surface chemistry were synthetized and assessed using the magnetic-assisted adsorption systems. One graphene oxide sample exhibited a dual magnetic behavior presenting both diamagnetic and ferromagnetic phases, while the other graphene oxide was diamagnetic. The adsorption properties of these graphene oxide samples for removing Pb2+ and Cu2+ were tested and compared with and without a magnetic field exposure. The results showed that the Pb2+ removal increased using both graphene oxide samples in the magnetic-assisted configuration, while Cu2+ adsorption was less sensitive to the application of the magnetic field. A monolayer model was used to simulate all the heavy metal adsorption isotherms quantified experimentally. It was concluded that the adsorption mechanism designed to remove Pb2+ and Cu2+ using tested graphene oxide samples was mainly multi-ionic where two metallic cations could interact with one active site (i.e., oxygenated functional groups) from the adsorbent surface. The oxygenated surface functionalities of graphene oxide samples played a relevant role in determining the impact of magnetic field exposure on the heavy metal removal efficacy. Magnetic-assisted adsorption using graphene oxide is an interesting alternative to reduce the concentration of Pb2+ in polluted effluents, and it can also be applied to improve the performance of adsorbents with a limited concentration of oxygenated functional groups, which usually show poor removal of challenging water pollutants such as toxic heavy metals. [ABSTRACT FROM AUTHOR]

In the present study, biopolymeric coatings of polyhydroxybutyrate (PHB) were deposited on 316L stainless steel substrates. The PHB coatings were developed using the spin coating method. To improve the adhesion of the PHB coating on the substrate, this method uses an atmospheric plasma treatment. Adhesion tests show a 156% increase in adhesion after 5 s of surface treatment. Raman spectroscopy analysis of the polymer shows the incorporation of functional groups and the formation of new hydrogen bonds, which can help us bind drugs and promote osteogenesis after plasma treatment. Additionally, the electrochemical behaviors in artificial body fluids (Hanks' solution) of the PHB coatings on the steel were evaluated with potentiodynamic tests, which revealed a decrease in the corrosion current and resistance to the transfer of the charge from the electrolyte to the 316L steel because of the PHB coating. All the PHB coatings were characterized using scanning electron microscopy and Raman spectroscopy after the electrochemical tests. This analysis confirmed the diffusion of electrolyte species toward the surface and the degradation of the polymer chain for the first 15 s of treatment with atmospheric plasma. These findings support the claim that plasma surface modification is a quick, environmentally friendly, and cost-effective method to enhance the performance of PHB coatings on 316L stainless steel for medical devices. [ABSTRACT FROM AUTHOR]

Centimeter to meter-sized volcanic ballistic projectiles from explosive eruptions jeopardize people and properties kilometers from the volcano, but they also provide information about the past eruptions. Traditionally, projectile trajectory is modeled using simplified ballistic theory, accounting for gravity and drag forces only and assuming simply shaped projectiles free moving through air. Recently, collisions between projectiles and interactions with plumes are starting to be considered. Besides theory, experimental studies and field mapping have so far dominated volcanic projectile research, with only limited observations. High-speed, high-definition imaging now offers a new spatial and temporal scale of observation that we use to illuminate projectile dynamics. In-flight collisions commonly affect the size, shape, trajectory, and rotation of projectiles according to both projectile nature (ductile bomb versus brittle block) and the location and timing of collisions. These, in turn, are controlled by ejection pulses occurring at the vent. In-flight tearing and fragmentation characterize large bombs, which often break on landing, both factors concurring to decrease the average grain size of the resulting deposits. Complex rotation and spinning are ubiquitous features of projectiles, and the related Magnus effect may deviate projectile trajectory by tens of degrees. A new relationship is derived, linking projectile velocity and size with the size of the resulting impact crater. Finally, apparent drag coefficient values, obtained for selected projectiles, mostly range from 1 to 7, higher than expected, reflecting complex projectile dynamics. These new perspectives will impact projectile hazard mitigation and the interpretation of projectile deposits from past eruptions, both on Earth and on other planets. [ABSTRACT FROM AUTHOR]

A 40-year-old woman was found to have bilateral Adie’s pupils and generalized muscle stretch areflexia. She did not have orthostatic hypotension but, in an ECG strip in the office, she appeared to have an almost fixed heart rate. We thus studied the heart rate variability (HRV) and the systolic blood pressure variability (SBPV) in supine and standing position and also during rhythmic breathing. We found a decreased HRV in the time domain with very low standard deviation in supine and standing position and during rhythmic breathing. HRV in the frequency domain was low with a decrease in the absolute power of HF and LF and a decrease in the sympathovagal balance in supine and standing positions. SBPV in the time and frequency domains was found to be normal. This patient with Holmes-Adie syndrome had an asymptomatic severe loss of HRV and a preserved SBPV. The global decrease in the HRV in the time and frequency domains indicated that she had both vagal and sympathetic cardiac denervation, whereas the preserved SBPV suggested normal innervation of the blood vessels. [ABSTRACT FROM AUTHOR]

In acute myeloid leukemia (AML), mutations of the Fms-like tyrosine kinase 3 receptor (FLT3) and its overexpression are related with hyperleukocytosis, higher risk of relapse, and decrease of both disease-free survival and overall survival. It has been suggested that this phenomenon confers proliferative and survival advantages to the malignant blast cells. As a consequence, it is an attractive therapeutic target. As the best treatment strategy for mutated FLT3 AML remains to be defined, the addition of FLT3 inhibitor drugs to chemotherapy or to the bone marrow transplant approach has become a growing strategy. With encouraging results, this combination seems to be an attractive option. Relevant data regarding the current treatment trends on mutated FLT3 AML is reviewed here. [ABSTRACT FROM AUTHOR]

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Our understanding of the reproductive biology of corals from the Mexican southeastern Pacific is limited, and consequently, the role of reproduction in structuring coral communities is unclear. As a first attempt to understand the importance of sexual reproduction in structuring and maintaining of the coral communities from this region, we documented the reproductive cycles over 2 years (2003-2004) in three main reef-building corals species in the region. Pocillopora damicornis was shown to be hermaphroditic with asynchronous gamete development observed only in 2004; P. gigantea was characterized as both gonochoric and cosexually hermaphroditic. Absence of mature gametes was documented in both species , and an observation may be attributed to the 2003 El Niño Southern Oscillation event, which may have inhibited reproductive maturation via thermal stress. Porites panamensis was gonochoric with asynchronous development, and planulae were generally brooded. The presence of mature gametes and planulae in P. panamensis polyps suggests that this species is an important contributor to local and, likely, regional recruitment of this species. Further research should seek to identify important source populations for these coral recruits and document the exchange of larvae between coral populations of the Mexican Pacific. [ABSTRACT FROM AUTHOR]

Fungal communities from gorgonians have been poorly documented and most studies of these communities have lacked defined sampling strategies. The objectives of this study were: (1) to estimate fungal diversity in Gorgonia ventalina; (2) to compare two sampling and tissue processing strategies: tissue fragments of different sizes vs. homogenized tissue. A total of seven genera and fourteen species of fungi were isolated on culture medium and identified by sequencing the nrITS. All but one species were new reports. In both treatments Aspergillus and Penicillium were the most common genera isolated. Most species isolated from fragments were not observed from homogenized tissue and vice versa. Reducing the size fragment increased significantly the number of species isolated per fragment. To better estimate fungal diversity in sea fans a strategy is proposed that combines sampling of small tissue fragments with homogenized tissue, since each technique yielded fungal species not detected by the other. [ABSTRACT FROM AUTHOR]

Traditional time domain techniques of data analysis are often not sufficient to characterize the complex dynamics of respiration. In this paper, the respiratory pattern variability is analyzed using symbolic dynamics. A group of 20 patients on weaning trials from mechanical ventilation are studied at two different pressure support ventilation levels, in order to obtain respiratory volume signals with different variability. Time series of inspiratory time, expiratory time, breathing duration, fractional inspiratory time, tidal volume and mean inspiratory flow are analyzed. Two different symbol alphabets, with three and four symbols, are considered to characterize the respiratory pattern variability. Assessment of the method is made using the 40 respiratory volume signals classified using clinical criteria into two classes: low variability (LV) or high variability (HV). A discriminant analysis using single indexes from symbolic dynamics has been able to classify the respiratory volume signals with an out-of-sample accuracy of 100%. [ABSTRACT FROM AUTHOR]