Entanglement purification is a vital protocol to produce a high-quality entangled state from an ensemble of identical states. Based on the particular scheme of entanglement purification [Phys. Rev. A87, 052316 (2013)], the effect of phase fluctuation is investigated. The convergence pattern of the initial states can be divided into two kinds of regions, corresponding to the purified outcomes being a maximally entangled state (MES) or a separable state. And there is the fractal-like structure near the boundary between these two regions. It is found that the phase noise plays a positive role in generating an MES for an initial states near some fractal boundary, which can only become the separable one if the noise is absent. It is also found that the minimal iteration steps to achieve the maximally entangled state with the phase noise can be decreased, which can save the resource in the protocol.
The Borexino experiment for solar neutrino physics and other rare phenomena requires an extremely low radioactive background to disentangle the very few events due to neutrino interactions. Therefore, the Borexino scintillator has to satisfy the most stringent radiopurity requirements, being about eight orders of magnitude less radioactive than an ordinary material. This was achieved by means of scintillator purification techniques and of a special care during all the production, handling and procurement of the scintillator solvent. This paper describes the methodology and the quality control procedures that were employed during the production, handling and shipping of the solvent.
Knowledge of distribution coefficient values is essential in estimating the refining efficiency, and plays an important role during the purification process, typically zone refining. The effective distribution coefficient "Keff" of impurities Se, Fe, Cr and Pb in tellurium was determined in the present study and found to be 0.48, 0.05, 0.25 and 0.19, respectively. The results are validated by comparing with the available published data, and we observed a difference of less than one order, which was reasonably comparable. The influence of "Keff" on zone refining efficiency was examined and it was noticed that the effective distribution coefficient increases with respect to the translation rate, which is minimum at an optimum lower translation rate (= 30 mm/h). The relative solute concentration C/C0 is determined experimentally, which shows the best fit of experimental values with Pfann's equation. The impurity profile along the length of the zone refined ingot is also discussed.
This research investigated the feasibility of effective cost filter materials for groundwater purification in the small and medium scale households in Vietnamese rural areas. The trial models could treat 30 L of groundwater with aeration flow 5 L/min for 15 min. After 24 h of sedimentation, the water was filtered through layers of gravel (h = 11 cm), sea sand (h = 11 cm), activated carbon (h = 15 cm), manganese sand (h = 12 cm), sea sand (h = 11 cm) and gravel (h = 11 cm). After treatment process, the concentration of Fe and Mn ions of the output trial models was lower than the Vietnamese standard for drinking water. The model has a simple structure and easy assembly for washing the filter materials which continued to be used for the next filtration process. These models provide in rural areas, where it promising solutions for supplying drinking water to households is difficult to get clean ground water.
We present an application of high-aspect-ratio (high-AR) silicon structures (black silicon) with high water repellency and good wettability by oils and solvents. The fabrication of black silicon consists of a deep reactive-ion etching process for extremely-high-AR silicon structures and surface treatment with C4F8 gas. Such high-AR structures were found to be highly resistant against wetting by water, but they also have good wetting characteristics with respect to certain liquids such as ethanol, hexane and mineral oil. To determine the relationship between the AR of nanostructures and wetting selectivity, four different black silicon samples with different pattern heights were used. The static contact angles of various liquid were measured for the analysis of wetting properties of the four black silicon samples. To explore feasible applications, ethanol–water separation was performed as a miniaturized experimental simulation of environmental remediation.
INDIA – A novel form of gene regulation in bacteria.
INDIA – Algal biofuels are no energy panacea.
JAPAN – Medical Data Vision enhances the quality of medical care with Actian Vectorwise.
SINGAPORE – Singapore heart surgeon to receive honour from The Royal College of Surgeons of Edinburgh.
SINGAPORE – ELGA® to deliver innovative water purification at new Singapore General Hospital expansion.
AUSTRALIA – Specialised Therapeutics Australia: New drug to fight hospital superbug infection.
AUSTRALIA – Group of genes hold the clue in migraine cases.
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BRAZIL – Science can do more for sustainable development.
MIDDLE EAST – Particles and persecution: why we should care about Iranian physicists.
EUROPE – Medicyte coordinates EU-funded collaboration on Biomimetic Bioartificial Liver.
EUROPE – Selvita and Orion Pharma achieve a research milestone in Alzheimer's Disease Program.
EUROPE – Zinforo (ceftaroline fosamil) receives positive CHMP opinion in the European Union for the treatment of patients with serious skin infections or community acquired pneumonia.
USA – Vein grown from girl's own stem cells transplanted.
USA – Hidden vitamin in milk yields remarkable health benefits - Weill Cornell researchers show tiny vitamin in milk, in high doses, makes mice leaner, faster and stronger.
USA – New report finds biotechnology companies are participating in 39% of all projects in development for new medicines and technologies for neglected diseases.
USA – TriReme Medical receives FDA clearance for expanded matrix of sizes of Chocolate PTA balloon catheter.
USA – New data show investigational compound dapagliflozin demonstrated significant reductions in blood sugar levels when added to sitagliptin in adults with type 2 diabetes at 24 weeks, with results maintained over 48 weeks.
USA – Zalicus successfully completes Phase 1 single ascending dose study with Z944, a novel, oral T-Type Calcium Channel Blocker.
USA – Study provides clues to clinical trial cost savings.
Imagene Labs Introduces Region’s First Complete Genetics-Based Wellness Solutions.
ASLAN Pharmaceuticals and A*STAR Enter RON Antibody Licensing and Research Collaboration Agreement.
Hidden HIV Revealed: New Insights into Latent HIV Infections.
Agilent Technologies Introduces Transformational Technology for Gas Chromatography.
Merck Joins DiViNe Consortium to Address Low Yields, High Costs of Vaccine Purification Processes.
FEI Celebrates Shipment of 1,000th Helios DualBeam System.
Complex chaos is specified by an iterated mapping on complex numbers. It has recently been found in the dynamics of qubits where each time step is conditioned on a measurement result on part of the system. We analyse the simplest case of one qubit dynamics with one complex parameter in some detail. We point out that two attractive cycles can exist and provide examples how the fractal like Julia set divides the areas of corresponding initial states. We show how to determine the set of parameters for which one, two or no stable fixed cycles exists and provide the numerically calculated images of the sets. The results can be relevant for the quantum state purification protocol based on the similar dynamics of two or more qubits and in general for any protocol based on conditioned nonlinear dynamics where truly chaotic behavior may occur.
We study in detail a very natural metric for quantum states. This new proposal has two basic ingredients: entropy and purification. The metric for two mixed states is defined as the square root of the entropy of the average of representative purifications of those states. Some basic properties are analyzed and its relation to other distances is investigated. As an illustrative application, the proposed metric is evaluated for one-qubit mixed states.
The effect of filtering operation with respect to purification and concentration of entanglement in quantum states are discussed in this paper. It is shown, through examples, that the local action of the filtering operator on a part of the composite quantum state allows for purification of the remaining part of the state. The redistribution of entanglement in the subsystems of a noise affected state is shown to be due to the action of local filtering on the non-decohering part of the system. The varying effects of the filtering parameter, on the entanglement transfer between the subsystems, depending on the choice of the initial quantum state is illustrated.
The practical potential of petroleum porphyrins still remains underestimated because of the absence of satisfactory simple and effective methods for their isolation in pure form. Our work aims to provide a solution for this problem via use of sulfuric acid loaded macroporous silica as an unprecedentedly effective adsorbent for deep petroporphyrin purification. Using chromatographic columns of reduced volume (4 cm3), a series of experiments on optimization of chromatographic conditions for silica-based sulfocationite were carried out. As a source of petroleum porphyrins, the primary concentrates of vanadyl porphyrins isolated on silica gel column from DMF extracts of heavy oil asphaltenes have been used. UV-vis and MALDI-TOF mass-spectrometric methods were employed for vanadyl porphyrin analysis and identification. We established that in a narrow range of water and acid content equal to ∼25 and ∼15 wt.%, respectively, silica-based sulfocationite becomes able to retain a bulk of polar petroleum components with exception of porphyrins, which thus leave the column first. A preparative-scale purification of vanadyl porphyrins by the sulfocationite-based method was performed for the first time and 18.5 mg of excellently pure product were obtained. Considering the extremely simple preparation and excellent purification performance of our novel sulfocationite, it could greatly facilitate access to high-purity petroleum porphyrins.
A quantum system interacting with a repeatedly measured one turns out to be subjected to a non-unitary evolution which can force the former to a specific quantum state. It is shown that in the case where the repeatedly measured system is subjected to the action of its environment, the occurrence of a competition between the dissipation and the measurements can reduce the influence of the decay on the filtering process. Both theoretical predictions and numerical results are presented.
Purification of carbon nanotubes (CNTs) is a very actively discussed topic in contemporary CNT literature. To a large extent, impurities embedded in CNTs influence the physical and chemical characteristics of the CNTs. Different purification methods yield different CNT characteristics and may be suitable for the production of different types of CNTs. Developments in the purification methods of CNTs are reviewed, and the production methods are briefly discussed and summarized. This is followed by a detailed description of the three major purification methods, viz. chemical, physical, and multi-step purification.
Multi-walled carbon nanotubes (MWCNTs) were prepared by floating catalyst (FC) method, using methane as a carbon source and iron (III) chloride (FeCl3) as a catalyst precursor, followed by purification with air oxidation and acid treatment. The as-grown and purified MWCNTs were characterized by transmission electron microscopy, scanning electron microscopy, energy dispersive spectroscopy, thermogravimetry analysis and Raman spectroscopy. The average inner and outer diameters of the MWCNTs were 25 and 39 nm, respectively. The purity and yield of the purified MWCNTs were more than 92% and 71% weight fraction, respectively.
New techniques and materials are called for wastewater treatment due to the shortage of worldwide fresh water and the increasing water demand. As a simple and efficient method, adsorption technique has been extensively applied to remove organic and inorganic pollutants from contaminated water. The application of carbon nanomaterials, such as activated carbon, carbon nanotubes (CNTs), graphenes and their derivatives/analogues, in wastewater treatment has also been investigated due to their unique properties, such as wide availability, porous structure, large surface area, tunable morphology and nontoxicity. This review highlights the recent advances of wastewater treatment utilizing carbon nanomaterial modified composites as adsorbents. The adsorption phenomenon and its mechanism are briefly discussed. Detailed discussions are focused on the selective adsorption of carbon nanomaterial composites to unique pollutants. The remaining challenges are also mentioned.
Boron carbide is one of the advanced ceramic materials which is used in a wide range of applications. However, this material needs a high sintering temperature (~2200°C). Using nano-size powders for producing ceramic parts results in lowering sintering temperature and also enhances toughness and hardness of the material. One of the methods for producing ceramic nano powders is attrition milling. However, as the milling balls and wall are made of steel, some impurities specially iron will be introduced to the powder during milling. Chemical analysis of the milled powder shows that more than 33wt% of the powder consists of iron. These uncontrolled impurities affect the mechanical and physical properties of sintered ceramic parts that are made of such a powder. Therefore, these impurities must be removed from the powder. Hydro metallurgical beneficiation technique with two different solvents has been used for purification of the powder. The result of chemical analysis after purification showed that the weight percentage of iron in powder dropped to 9% and 0.8% (depending on the solvents). Moreover, the sintering behavior of hot-pressed boron carbide powder with different percentages of iron as sintering aid has been studied. The results showed excellent densification and hardness of the sintered parts.
Growth factors such as human epidermal growth factor (hEGF) have recently received high interest in regenerative medicine and pharmaceutical industries mainly due to their ability to restore tissues proliferation and improvement of their biological functions. In spite of various hEGF applications, its efficient expression in Escherichia coli could not yet reach an industrial reality mainly due to the lack of the ability of folding into the correct 3D structure because of three disulfide bonds in monomer hEGF. To address these challenges, here a fusion hEGF protein with a C terminus of collagen binding domain (CBD) along with intein protein with self-splicing property and ELP sequence was constructed by a three-step cloning procedure. This enabled us to purify recombinant hEGF without using chromatography columns. Following the confirmation of the construct by colony PCR, restriction enzymes analysis and sequencing, the 62kDa band of ELP-INTEIN-hEGF-CBD were observed on SDS-PAGE and confirmed by western blotting. Subsequently, the mitotic activity in Balb/c 3T3 cells proliferation in presence of recombinant hEGF-CBD compared with commercial hEGF using methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay which showed that our purified recombinant protein stimulates the cell proliferation similar to the commercial protein. Our strategy could be considered as a new feasible approach to produce hEGF in E. coli for pharmaceutical and clinical applications.
Adult articular cartilage tissue has poor capability of self-repair. Therefore, a variety of tissue engineering approaches are motivated by the clinical need for articular repair. Alginate has been used as a biomaterial for cartilage regeneration. The alginate is a natural polymer that is extracted from seaweeds and purification. However, the main drawback is the immune rejection in vivo. To overcome this problem, we have developed the biocompability of alginate using modified Korbutt method. After alginate was purified, purified alginate microcapsules were used in cartilage regeneration. Chondrocytes were seeded in purified and nonpurified alginate microcapsules, and then cell viability, proliferation and phenotype were analyzed by 3-(4,5-dimethylthiazol-2-yl)-2,5 diphenyltetrazolium bromide (MTT) assay. Reverse transcriptase-polymerase chain reaction (RT-PCR) was conducted to confirm mRNA expression on collagen type I and collagen type II for chondrocytes phenotype. Hematoxylin and eosin (H&E) and Safranin-O histological staining showed tissue growth at the interface during the first 10 days. In this study, chondrocytes in purified alginate microcapsules had higher cell viability, proliferation and more phenotype expression than those in nonpurified alginate microcapsules. The results suggest that the purified alginate microcapsule is useful for cartilage regeneration.
The potential therapeutic value of bromelain is due to its biochemical and pharmacological properties and hence, it is desired to obtain bromelain in its highest purified form. Crude bromelain extract can be obtained from the fruit of Ananas comosus using ion exchange chromatography. Bromelain thus obtained can be subjected to either spray or freeze drying. The resulting residual activity and the specific activity were compared between the spray and freeze dried powders. Freeze dried bromelain was found to posses the specific activity twice as compared to the spray dried powder. The effect of protective agents and the bulking agents on the retention of activity was studied in both spray as well as freeze drying. The initial results have been encouraging as 90 % of the bromelain recovery was possible.
Cholera toxin B subunit (CTB) mature protein was stably expressed in transgenic tobacco plants under the control of CaMV 35S promoter and TMV Ω fragment. Fusion of the PR1b signal peptide coding sequence to the CTB mature protein gene increased the expression level by 24-fold. The tobacco-synthesized CTB (tCTB) was purified to homogeneity by a single step of immunoaffinity chromatography. The purified tCTB is predominantly in the form of pentamers with molecular weight identical to the native pentameric CTB, indicating the PR1b-CTB fusion protein has been properly processed in tobacco cells. Futhermore, we have shown that the antigenicity of the purified tCTB is indistinguishable from that of the native CTB protein by immunodiffusion and immunoelectrophoresis.
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