2,212 research outputs found
Role of the cluster structure of Li in the dynamics of fragment capture
Exclusive measurements of prompt -rays from the heavy-residues with
various light charged particles in the Li + Pt system, at an energy
near the Coulomb barrier (E/ 1.6) are reported. Recent dynamic
classical trajectory calculations, constrained by the measured fusion,
and capture cross-sections have been used to explain the excitation energy
dependence of the residue cross-sections. These calculations distinctly
illustrate a two step process, breakup followed by fusion in case of the
capture of and clusters; whereas for He + and He +
configurations, massive transfer is inferred to be the dominant mechanism.
The present work clearly demonstrates the role played by the cluster structures
of Li in understanding the reaction dynamics at energies around the Coulomb
barrier.Comment: 6 pages, 4 figures, Accepted for publication in Phys. Letts.
In Vitro Effect on Plasmodium falciparum and In Vivo Effect on Plasmodium berghei of Annomaal, an Oily Fraction Obtained from the Seeds of Annona squamosa
Malaria remains a life-threatening health problem and is responsible for the high rates of mortality and morbidity in the tropical and subtropical regions of the world. The increasing threat of drug resistance to available artemisinin-based therapy warrants an urgent need to develop new antimalarial drugs that are safer, more effective, and have a novel mode of action. Natural plants are an excellent source of inspiration in searching for a new antimalarial agent. This research reports a systematic investigation for determining the antimalarial potential of the seeds of A. squamosa. The study shows that the crude seed extract (CSE), protein, saponin, and the oily fractions of the seeds were nontoxic at a 2000 mg/kg body weight dose when tested in Wistar rats, thus revealing high safety is classified as class 5. The oily fraction, Annomaal, demonstrated pronounced antimalarial activity with low IC50 (1.25 ± 0.183 μg/mL) against P. falciparum in vitro. The CSE and Annomaal significantly inhibited the growth of P. berghei parasites in vivo with 58.47% and 61.11% chemo suppression, respectively, while the standard drug artemether showed chemo suppression of 66.75%. Furthermore, the study demonstrated that oral administration of Annomaal at a daily dose of 250 mg/kg/day for 3 days was adequate to provide a complete cure to the P. berghei-infected mice. Annomaal thus holds promise as being patient-compliant due to the shorter treatment schedule, eliminating the need for frequent dosing for extended time periods as required by several synthetic antimalarial drugs. Further studies are needed to determine the active compounds in the oily fraction responsible for antimalarial activity
Internet of things
Manual of Digital Earth / Editors: Huadong Guo, Michael F. Goodchild, Alessandro Annoni .- Springer, 2020 .- ISBN: 978-981-32-9915-3Digital Earth was born with the aim of replicating the real world within the digital world. Many efforts have been made to observe and sense the Earth, both from space (remote sensing) and by using in situ sensors. Focusing on the latter, advances in Digital Earth have established vital bridges to exploit these sensors and their networks by taking location as a key element. The current era of connectivity envisions that everything is connected to everything. The concept of the Internet of Things(IoT)emergedasaholisticproposaltoenableanecosystemofvaried,heterogeneous networked objects and devices to speak to and interact with each other. To make the IoT ecosystem a reality, it is necessary to understand the electronic components, communication protocols, real-time analysis techniques, and the location of the objects and devices. The IoT ecosystem and the Digital Earth (DE) jointly form interrelated infrastructures for addressing today’s pressing issues and complex challenges. In this chapter, we explore the synergies and frictions in establishing an efficient and permanent collaboration between the two infrastructures, in order to adequately address multidisciplinary and increasingly complex real-world problems. Although there are still some pending issues, the identified synergies generate optimism for a true collaboration between the Internet of Things and the Digital Earth
MesonNet 2013 International Workshop. Mini-proceedings
The mini-proceedings of the MesonNet 2013 International Workshop held in
Prague from June 17th to 19th, 2013, are presented. MesonNet is a research
network within EU HadronPhysics3 project (1/2012 -- 12/2014). The web page of
the conference, which contains all talks, can be found at
http://ipnp.mff.cuni.cz/mesonnet13Comment: 106 pages, 53 contributions. Mini-proceedings of the MesonNet 2013
International Workshop. Editors: K. Kampf, A. Kupsc, and P. Masjua
CEREBROSIDE GALACTOSIDASE: A METHOD FOR DETERMINATION AND A COMPARISON WITH OTHER LYSOSOMAL ENZYMES IN DEVELOPING RAT BRAIN 1
(1) A method is described for assaying brain for cerebroside galactosidase activity. The enzyme was liberated by sonication and addition of sodium taurocholate, then by digestion with pancreatic enzymes. It was further purified by precipitation at pH 3. The enzyme was then incubated with an emulsion of galactose-labelled cerebroside in taurocholate and oleate at pH 4·5, and the liberated galactose was determined by scintillation counting. (2) The content of cerebroside galactosidase in rat brain at various ages has been determined. The enzyme was present before cerebroside appears in noticeable amounts (4 days) and the amount rose considerably during the period of active cerebroside deposition and myelination. The amount then remained at a high concentration even in the adult. (3) Comparison with other lysosomal brain enzymes was made in the age study. Nitrophenyl galactoside hydrolase also increased during myelination but levelled off earlier; its activity paralleled the amount of ganglioside. Nitrophenyl glucoside hydrolase started at a lower level and decreased with age. Sulphatase activity rose during myelination, then decreased somewhat after 15 days. Ceramidase followed a pattern similar to that of nitrophenyl galactoside hydrolase; it is suggested that both of these enzymes reflect ganglioside metabolism. (4) The relative amounts of brain enzymes in different states were determined as a function of age in the case of cerebrosidase, nitrophenyl galactoside hydrolase and sulphatase. The proportion found in the high speed supernatant fraction was low but increased after myelination. The proportion that could be ‘solubilized’ by sonication decreased after myelination but the values differed greatly for the three enzymes. This treatment solubilized one-seventh of the cerebrosidase, half the nitrophenyl galactosidase and three-quarters of the sulphatase.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66425/1/j.1471-4159.1969.tb06849.x.pd
Evidence of a new shell closed nucleus governing slow quasi-fission
Mass distributions of fission fragments arising from the slow quasi-fission
process have been derived by comparing the measured distributions with the
theoretical distributions based on compound nuclear fission model for several
reactions. The mass-distributions corresponding to quasi-fission events for all
the systems show the following common features: (1) they are double peaked with
fixed peak-centroids and nearly same width at different incident energies, (2)
the yield of quasi-fission events decreases with the increasing projectile
energy, and (3) peak corresponding to lighter fragment is observed at A
96 for all the systems, whereas the peak of heavier fragment increases linearly
with the mass of the di-nuclear system. All the above observations are quite
similar to the ones observed in well known asymmetric fission of actinides,
thus providing clear evidences of shell effect in slow quasi-fission where the
lighter fragment is possibly nuclei around Zr, a new doubly magic
nucleus. This finding has great implications in the study of nuclear reactions,
structure and particularly in super-heavy element synthesis where quasi-fission
is synonymous
Modification of Hydrophilic and Hydrophobic Surfaces Using an Ionic-Complementary Peptide
Ionic-complementary peptides are novel nano-biomaterials with a variety of biomedical applications including potential biosurface engineering. This study presents evidence that a model ionic-complementary peptide EAK16-II is capable of assembling/coating on hydrophilic mica as well as hydrophobic highly ordered pyrolytic graphite (HOPG) surfaces with different nano-patterns. EAK16-II forms randomly oriented nanofibers or nanofiber networks on mica, while ordered nanofibers parallel or oriented 60° or 120° to each other on HOPG, reflecting the crystallographic symmetry of graphite (0001). The density of coated nanofibers on both surfaces can be controlled by adjusting the peptide concentration and the contact time of the peptide solution with the surface. The coated EAK16-II nanofibers alter the wettability of the two surfaces differently: the water contact angle of bare mica surface is measured to be <10°, while it increases to 20.3±2.9° upon 2 h modification of the surface using a 29 µM EAK16-II solution. In contrast, the water contact angle decreases significantly from 71.2±11.1° to 39.4±4.3° after the HOPG surface is coated with a 29 µM peptide solution for 2 h. The stability of the EAK16-II nanofibers on both surfaces is further evaluated by immersing the surface into acidic and basic solutions and analyzing the changes in the nanofiber surface coverage. The EAK16-II nanofibers on mica remain stable in acidic solution but not in alkaline solution, while they are stable on the HOPG surface regardless of the solution pH. This work demonstrates the possibility of using self-assembling peptides for surface modification applications
Clinical experience with the Bicarbon heart valve prosthesis
BACGROUND: We have previously reported mid-term results of a study, which ended in January 2000, on the Bicarbon valve. The study concluded that the valve showed excellent clinical results, associated with a low incidence of valve-related complications. In the present study, the same patients were prospectively followed for an additional 5 years. METHODS: Forty-four patients had aortic valve replacement (AVR), 48 had mitral valve replacement (MVR), and 13 had both aortic and mitral valve replacement (DVR). The mean age of the 105 patients was 61.2 ± 11.3 years. The mean follow-up was 6.1 ± 1.9 years with a cumulative follow-up of 616 patient-years. RESULTS: There were 5 early deaths (4.7%: 4 in the AVR group and 1 in the MVR group) and 21 late deaths (3.4%/patient-year: 5 valve related deaths and 16 valve unrelated deaths). Survival at 8 years was 75.2 ± 7.0% in the AVR group, 76.6 ± 6.2% in the MVR group, and 55.4 ± 16.1% in the DVR group. The linearized incidence of thrombo-embolic complications, hemorrhagic complications, and paravalvular leaks in all patients was 0.65 ± 1.48%, 0.81 ± 1.69%, and 0.16 ± 0.54%/patient-year respectively. No other complications were observed. CONCLUSION: The Bicarbon prosthetic heart valve has shown excellent long-term clinical results, associated with a low incidence of valve-related complications
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