10,991 research outputs found
Synthesis and application of zeolite and glass fiber supported zero valent iron nanoparticles as membrane component for removal nitrate and Cr (+6) ions
In the present paper the synthesis and characterization of zeolite and glass fiber supported zero valent iron
nanoparticles (Ze-ZVI, GF-ZVI NPs) are reported.ZVI, Ze-ZVI and GF-ZVI NPs size, composition and
morphology were characterized by Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM),
Energy Dispersive Spectroscopy (EDS). Synthesized nanostructures were tested as reducing agents of nitrate
and hexavalent Chromium. Batch experiments were carried for revealing of efficacy of prepared nanomaterials
(ZE-ZVI NPs and GF-ZVI NPs). Nitrate removal efficiency (at initial concentration 50 mg/mL) was rapidly
increased from 26% to 76% for GF-ZVI NPs at 60-240 min time interval for and from 34% to 90% for ZE-ZVI
NPs at the same time interval.Also was studied the efficacy of prepared nanostructures ZE-ZVI and ZE-ZVI
NPs as membrane component with 5% of ZVI NPS weight contentfor the removal of nitrate from water
solution that made 85% for ZE-ZVI NPs and 76% for GF-ZVI NPs, respectively. The results of this study
indicate that the application of GF-ZVI and ZE-ZVI NPs as membrane component is advantageous because it
allows to prevent the additional pollution of treated solution caused by unreacted ZVI NPs
Cannabinoids in the treatment of epilepsy: current status and future prospects
Cannabidiol (CBD) is one of the prominent phytocannabinoids found in Cannabis sativa, differentiating from Î9-tetrahydrocannabinol (THC) for its non-intoxicating profile and its antianxiety/antipsychotic effects. CBD is a multi-target drug whose anti-convulsant properties are supposed to be independent of endocannabinoid receptor CB1 and might be related to several underlying mechanisms, such as antagonism on the orphan GPR55 receptor, regulation of adenosine tone, activation of 5HT1A receptors and modulation of calcium intracellular levels. CBD is a lipophilic compound with low oral bioavailability (6%) due to poor intestinal absorption and high first-pass metabolism. Its exposure parameters are greatly influenced by feeding status (ie, high fatcontaining meals). It is mainly metabolized by cytochrome P 450 (CYP) 3A4 and 2C19, which it strongly inhibits. A proprietary formulation of highly purified, plant-derived CBD has been recently licensed as an adjunctive treatment for Dravet syndrome (DS) and Lennox-Gastaut syndrome (LGS), while it is being currently investigated in tuberous sclerosis complex. The regulatory agenciesâ approval was granted based on four pivotal double-blind, placebocontrolled, randomized clinical trials (RCTs) on overall 154 DS patients and 396 LGS ones, receiving CBD 10 or 20 mg/kg/day BID as active treatment. The primary endpoint (reduction in monthly seizure frequency) was met by both CBD doses. Most patients reported adverse events (AEs), generally from mild to moderate and transient, which mainly consisted of somnolence, sedation, decreased appetite, diarrhea and elevation in aminotransferase levels, the last being documented only in subjects on concomitant valproate therapy. The interaction between CBD and clobazam, likely due to CYP2C19 inhibition, might contribute to some AEs, especially somnolence, but also to CBD clinical effectiveness. Cannabidivarin (CBDV), the propyl analogue of CBD, showed anti-convulsant properties in pre-clinical studies, but a plant-derived, purified proprietary formulation of CBDV recently failed the Phase II RCT in patients with uncontrolled focal seizures
Role of structure of the Pp/magnetite nanocomposites on their thermal properties
The thermal degradation behaviour of polypropylene and its magnetite composites have been investigated by
differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). Distribution of magnetite
nanoparticles in a polymer matrix has been studied by scanning and transmission electron microscopy and also
atomic force microscopy. The thermal and mechanical properties of nanocomposites based on polypropylene
and magnetite nanoparticles have also been investigated. It has shown that, the introduction of Fe3O4
nanoparticles in polypropylene increases its thermal stability of about 1000C. The maximum increase in the
thermal stability of PP was observed in the case of a 20% weight content of Fe3O4 nanoparticles in
polypropylene
An Update on Circular RNA in Pediatric Cancers
Circular RNAs (circRNAs) are a class of single-stranded closed noncoding RNA molecules which are formed as a result of reverse splicing of mRNAs. Despite their relative abundance, only recently there appeared an increased interest in the understanding of their regulatory importance. Among their most relevant characteristics are high stability, abundance and evolutionary conservation among species. CircRNAs are implicated in several cellular functions, ranging from miRNA and protein sponges to transcriptional modulation and splicing. Additionally, circRNAsâ aberrant expression in pathological conditions is bringing to light their possible use as diagnostic and prognostic biomarkers. Their use as indicator molecules of pathological changes is also supported by their peculiar covalent closed cyclic structure which bestows resistance to RNases. Their regulatory role in cancer pathogenesis and metastasis is supported by studies involving human tumors that have investigated different expression profiles of these molecules. As endogenous competitive RNA, circRNAs can regulate tumor proliferation and invasion and they arouse great consideration as potential therapeutic biomarkers and targets for cancer. In this review, we describe the most recent findings on circRNAs in the most common pediatric solid cancers (such as brain tumors, neuroblastomas, and sarcomas) and in more rare ones (such as Wilms tumors, hepatoblastomas, and retinoblastomas)
Decoherence by Correlated Noise and Quantum Error Correction
We study the decoherence of a quantum computer in an environment which is
inherently correlated in time and space. We first derive the nonunitary time
evolution of the computer and environment in the presence of a stabilizer error
correction code, providing a general way to quantify decoherence for a quantum
computer. The general theory is then applied to the spin-boson model. Our
results demonstrate that effects of long-range correlations can be
systematically reduced by small changes in the error correction codes.Comment: 4 pages, 1 figure, Phys. Rev. Lett. in pres
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The characterization, management, and future considerations for ErbB-family TKI-associated diarrhea.
PurposeDiarrhea is recognized as a common adverse event associated with tyrosine kinase inhibitors (TKIs), with those targeting the ErbB family of receptors being associated with the highest rate of diarrhea.MethodsThis paper reviews data on the incidence, timing, and duration of diarrhea associated with US Food and Drug Administration-approved ErbB family-targeted TKIs from the published literature, and sets forth recommendations for management.ResultsIn the absence of anti-diarrheal prophylaxis the incidence of any-grade diarrhea varies and typically occurs early during the course of treatment. Although it is difficult to determine if the incidence and severity of diarrhea is related to inhibition of a particular kinase target because of the multi-targeted and overlapping activity of many agents, evidence suggests that second-generation TKIs with broader target profiles (i.e., afatinib, lapatinib, neratinib) result in a higher incidence of diarrhea compared with highly specific first- (erlotinib, gefitinib) or third- (osimertinib) generation agents. The mechanisms responsible for TKI-associated diarrhea are not fully understood and are likely multi-factorial, involving dysregulated ion transport, inflammation, and mucosal injury. Management strategies have been developed-and continue to be refined-to prevent and reduce the severity and duration of TKI-associated diarrhea. For agents associated with more significant symptoms, anti-diarrheal prophylaxis reduces the incidence and severity of diarrhea, and ongoing studies are evaluating specific strategies to further reduce incidence and duration of TKI-associated diarrhea.ConclusionsContinued investigations into risk factors and pharmacogenomic markers for diarrhea may further improve management of this common toxicity
Threeâway compositional data: a multiâstage trilinear decomposition algorithm
The CANDECOMP/PARAFAC model is an extension of bilinear PCA
and has been designed to model three-way data by preserving their multidimensional
configuration. The Alternating Least Squares (ALS) procedure is the preferred
estimating algorithm for this model because it guarantees stable results. It
can, however, be slow at converging and sensitive to collinearity and over-factoring.
Dealing with these issues is even more pressing when data are compositional and
thus collinear by definition. In this talk the solution proposed is based on a multistage
approach. Here parameters are optimized with procedures that work better for
collinearity and over-factoring, namely ATLD and SWATLD, and then results are
refined with ALS
Information-flux approach to multiple-spin dynamics
We introduce and formalize the concept of information flux in a many-body
register as the influence that the dynamics of a specific element receive from
any other element of the register. By quantifying the information flux in a
protocol, we can design the most appropriate initial state of the system and,
noticeably, the distribution of coupling strengths among the parts of the
register itself. The intuitive nature of this tool and its flexibility, which
allow for easily manageable numerical approaches when analytic expressions are
not straightforward, are greatly useful in interacting many-body systems such
as quantum spin chains. We illustrate the use of this concept in quantum
cloning and quantum state transfer and we also sketch its extension to
non-unitary dynamics.Comment: 7 pages, 4 figures, RevTeX
Review on the effects of physical activity on body composition and shape in people with down syndrome
People with Down Syndrome (DS) are often characterized by overweight or obesity and result to be less active than their peers. Both overweight/obesity and physical inactivity are considered important risk factors for health, thus augmenting mortality risk. World Health Organization recommends different training programmes for health benefits in different age ranges of general population. Effects of physical activity may be even more important in preventing health consequences in people with DS. In this context, we conducted a literature search of original articles, published between May 2010 and May 2020, on the effects of physical activity on body shape, body composition and bone quality in people with DS. We found twelve articles from all the continents, investigating the effects of different types of physical activity on body fat and lean masses, bone composition and anthropometry. In sum, the included studies reported improvements in body composition (with augmented lean mass and reduced fat mass), body size (with lower weight, waist circumference and BMI) and bone quality (in terms of bone mineral content and/or bone mineral density). In particular, body composition improves after conditioning and plyometric jumps training program, 2-wheel bicycle training, whole body vibration and swimming. Body shape is significantly improved by bicycle training, interval training and swimming. Finally, bone quality shows positive results after conditioning and plyometric jumps training program, whole body vibration and weight bearing exercise. Although different types of physical activity are investigated in people with DS, however the best training programme for this population is not clear. So future studies may focus on the comparison or combination of different types of physical activity to assess which one could maximize benefits
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