36 results about "Functional stability" patented technology

The invention relates to a self-cleaning nano coating material and a preparation process thereof, and belongs to the technical field of functional coatings. The coating material is prepared from nano silicon dioxide, nano aluminum oxide, graphene nanosheets, nitrogen-doped titanium dioxide, fluorinated silane, polyurethane, polydimethylsiloxane, a microcapsule repairing system, ethanol and deionized water according to a specific proportion through a multi-layer composite structure. The preparation process comprises the steps of base material surface pretreatment, reinforced particle surface modification, base material dissolution, functional additive introduction and multi-layer coating preparation. Through bottom layer enhancement, middle layer flexible buffering and surface layer functional design, excellent mechanical strength, wide-spectrum photocatalytic performance, self-repairing capacity and environmental adaptability are achieved. The problems that in the prior art, a self-cleaning coating is insufficient in mechanical performance, low in photocatalytic efficiency, lack of a self-repairing function and poor in weather resistance are solved, the service life of the coating is remarkably prolonged, and the functional stability of the coating is remarkably improved.

Provided are variant Cas12f4 polypeptides, fusion proteins containing variant Cas12f4 polypeptides, nucleic acids encoding variant Cas12f4 polypeptides and fusion proteins, compositions and methods related to those variant Cas12f4 polypeptides and fusion proteins, and modified host cells comprising the variant Cas12f4 polypeptides and / or encoding nucleic acids. The variant Cas12f4 polypeptides disclosed herein exhibit improved functionality, stability, and / or other desirable properties and may be used in combination with guide Cas12f4 RNAs that can be used in a variety of applications ex vivo, in vitro, and in vivo.

The present disclosure relates to compositions, methods, processes, kits and devices for selecting, designing, preparing, manufacturing, formulating and / or using polynucleotides having internal ribosome entry site (IRES) sequences, IRES-like sequences, or combinations thereof. In particular, the present disclosure relates to compositions, methods, processes, kits and devices for selecting, designing, preparing, manufacturing, formulating and / or using cyclic polynucleotides (e.g., cyclic RNAs). The present disclosure also relates to methods of improving expression, functional stability, immunogenicity, ease of manufacture and / or half-life of therapeutic products encoded by the circular RNA.

The invention discloses a construction method of a human epidermal organoid, and belongs to the technical field of organoid cell culture. The method is mainly used for optimizing a culture method of human epidermal organoid, and particularly relates to an efficient epidermal organoid culture technology based on a specific culture medium and an enzyme digestion system. According to the method, a # imgabs0 # human epidermal organ complete culture medium is adopted for preparation, and a basic culture medium and an additive are mixed to form the complete culture medium suitable for cell growth. The primary specimens are treated, and the steps of cleaning, digestion, cell collection and the like are included, so that the activity and functions of cells are ensured. Through accurate inoculation and culture conditions, the formation and growth of the organoid are promoted, and the culture in a proper environment is ensured, so that the formation efficiency of the organoid is improved. The organoid is subjected to passage and cryopreservation treatment, so that the activity and functional stability of the organoid in the long-term storage and use process are ensured.

A method and system for guiding joint replacement procedures based on functional stability analysis of a joint. The method comprises communicatively connecting to a plurality of sensors worn by an individual at muscles in a joint area and performing an initial measurement that evaluates strength and activity level of the muscles. The initial measurement includes a recording of data values from the plurality of sensors during a preoperative testing procedure. The initial measurement is compared with reference data, wherein the reference data includes measurements of healthy people with normal muscle function. The method further comprises generating joint replacement recommendations based on the comparison.

Circular RNA and precursor RNA polynucleotides, along with related compositions and methods are described herein. In some embodiments, the circular RNA comprises, in the following order, a 3' self-spliced exon segment, an intervening region, and a 5' self-spliced exon segment. In some embodiments, the precursor RNA is a linear RNA comprising a 5' combined accessory element comprising a 3' permuted intron segment; an intervening region; and a 3' combined accessory element comprising a 5' permuted intron segment. In some embodiments, the circular RNA and / or precursor RNA polynucleotides comprise a coding region comprising an expression sequence. In some embodiments, the precursor RNA polynucleotide comprises a monotron. In some embodiments, the circular RNA has improved expression, functional stability, immunogenicity, ease of manufacturing, and / or half-life when compared to linear RNA. In some embodiments, the methods and constructs result in improved circularization efficiency and / or splicing efficiency as compared to a control RNA polynucleotide comprising a native intronic sequence. Also provided herein are precursor RNA polynucleotides, circular RNA polynucleotides, and DNA polynucleotides, including polynucleotides comprising at least one modified A, C, G, or U nucleotide or nucleoside. Also presented herein are methods and compositions for the manufacture and preparation of circularized RNAs, along with methods of administering said circular RNAs and related compositions to a subject in need thereof for treatment or prevention purposes.

The invention discloses a low-color-interference high-stability water-based marking environment-friendly coating and a production method thereof, and relates to the technical field of curing coatings. The invention discloses a low-color-interference high-stability water-based marking environment-friendly coating. The coating is prepared from the following components in parts by mass: 40-60 parts of base resin, 30-40 parts of wear-resistant filler, 0.5-1.5 parts of a dispersing agent, 0.1-0.5 part of a defoaming agent, 1-3 parts of a coalescing agent, 0.1-0.5 part of a thickening agent, 1-3 parts of an anti-freezing agent, 0.5-2 parts of an antioxidant and 10-20 parts of deionized water. By adding the antioxidant with a specific structure, the problems of discoloration, aging and the like caused by oxidation of the coating are effectively inhibited, the service life of the coating is remarkably prolonged, and the attractiveness and functional stability of marked lines are improved.

The invention provides a regulatory T cell with improved phenotype and functional stability and a preparation method and application thereof. The regulatory T cell disclosed by the invention is co-expressed by membrane protein GARP and TGF-beta, and specifically, the TGF-beta comprises a C33S point mutation precursor TGF-beta 1; further, the regulatory T cell co-expresses a cytokine and a sorting marker, specifically, the cytokine comprises IL-10, and the sorting marker comprises a truncated nerve growth factor receptor tNGFR. The regulatory T cell has more stable phenotype and function stability in in-vivo and in-vitro environments, has important enlightenment value for improving the function stability problem of the regulatory T cell in an inflammatory environment, and has wide application prospects in the fields of treatment of autoimmune diseases, intervention of organ transplantation rejection and the like.

The invention relates to the field of food / medicine auxiliary materials, in particular to a compound functional starch composition and a preparation method thereof. The compound functional starch composition is prepared from the following raw materials in parts by mass: 65 to 100 parts of compound starch matrix, 1 to 5 parts of thickening agent, 3 to 6 parts of water-retaining agent, 1 to 3 parts of compatilizer, 0.1 to 0.3 part of antioxidant, 3 to 5 parts of microcrystalline cellulose, 1 to 3 parts of citric acid, 0.5 to 1.5 parts of sodium trimetaphosphate, 3 to 6.5 parts of functional anhydride and 180 to 250 parts of deionized water. The finally prepared composite functional starch composition not only has excellent functionality, but also can maintain good storage stability, compatibility stability and freeze-thaw stability, and can endow the starch composition with good processing application performance while improving the loading efficiency of the composite functional starch composition. Therefore, the functionality and the functional stability of the starch composition are greatly improved, the application range of the starch composition in the field of food / medicine auxiliary materials is expanded, and the starch composition has a very excellent application prospect.

The invention relates to a composite coating structure with a low-ductility functional coating matched with a high-ductility base material, the composite coating structure covers the surface of a base material, a coating formed by combining a low-ductility material and a high-ductility material is adopted, the low-ductility material is an active material which plays a role, and the high-ductility material is an active material which plays a role. The low-ductility material and the high-ductility material form reticular structure pattern distribution in the composite coating structure, the high-ductility material forms a framework of a reticular structure, and the low-ductility material is embedded into each unit body defined by the framework. Compared with the prior art, the method has the advantages that the ductility of the low-ductility functional coating is improved, so that the low-ductility functional coating is matched with a high-ductility substrate material, and the mechanical property and the functional stability of the original functional coating are improved.

The invention discloses a preparation method and application of an algae cell extract doped chitosan active composite membrane. Specifically, chitosan is adopted as a matrix, and two kinds of algal oil are introduced to enhance the functional performance of the membrane: one kind is that chlorella oil is directly doped into a chitosan solution, and the membrane is formed through a solution casting method, so that the mechanical performance and the antioxidant activity of the membrane can be effectively improved; and the other method comprises the following steps: combining schizochytrium limacinum oil with soybean protein isolate, preparing a stable Pickering emulsion by adopting an ultrasonic-assisted method, then mixing the stable Pickering emulsion with a chitosan matrix, and remarkably improving the homogeneity, the mechanical property and the functional stability of the membrane after the membrane is formed. The film material has good film-forming property, biodegradability and wide food fresh-keeping application potential.

The invention belongs to the technical field of yeast strains and fermentation, and discloses a yeast S19k and application thereof. The strain is hansenula polymorpha S19K. According to the method, the exclusive strain S19k of the red wine is screened, and a sequential inoculation process is combined, so that the limitation of the prior art in the aspects of aroma complexity, color stability and environmental tolerance is broken through, and a differentiated solution is provided for producing area personalization of the domestic red wine. According to the invention, a traditional single enzyme activity screening mode is broken through, a comprehensive screening system of the bacterial strain and the enzyme produced by the bacterial strain in a gradient wine brewing stress environment is constructed, and the functional stability of the bacterial strain in a real brewing environment is ensured. Compared with existing patents, the strain specificity, the metabolism regulation and control mechanism and the industrial adaptability are remarkably innovated, and higher market competitiveness and technical barriers are achieved.

The present application belongs to the field of nutritional composition and biological medicine technology, and particularly relates to a composition for protecting and preserving liver, a preparation method, application and product thereof. The composition of the present application is composed of extract of Silybum marianum, glucoraphanin and extract of Cynara scolymus. The composition of the present application can intervene the pathological process of liver injury from multiple dimensions such as antioxidation, anti-inflammation, regulation of lipid metabolism and repair of hepatocytes through synergistic effect of the three components, significantly reduces the levels of glutamic-pyruvic transaminase and glutamic-oxalacetic transaminase, reduces the accumulation of liver fat, improves the antioxidant capacity of the body, effectively prevents or improves alcoholic, chemical, non-alcoholic fatty and autoimmune liver injury, delays the progression of liver fibrosis, and comprehensively maintains the structural integrity and functional stability of the liver.

The present disclosure relates to compositions, methods, processes, kits and devices for the selection, design, preparation, manufacture, formulation, and / or use of a polynucleotide having an Internal Ribosome Entry Site (IRES) sequence, an IRES-like sequence or a combination thereof. In particular, the present disclosure relates to compositions, methods, processes, kits and devices for the selection, design, preparation, manufacture, formulation, and / or use of a circular polynucleotide (e.g., a circular RNA). The present disclosure also relates to a method of improving expression, functional stability, immunogenicity, ease of manufacturing and / or half-life of a therapeutic product encoded by the circular RNA.

The present application relates to the technical field of biological medicine, in particular to a cell preservation composition beneficial to long-distance transportation of cells and a preparation process and application thereof, the composition realizes high survival rate and functional stability of cells in long-distance transportation and short-term storage through synergistic effect of specific active ingredients and serum-free substitutes, combined with buffer system and cytokine support.

The invention discloses a synthetic flora for enhancing drought resistance of corn and application of the synthetic flora, and belongs to the technical field of plant stress resistance. The invention discloses a synthetic flora capable of enhancing drought resistance of corn. The synthetic flora is prepared by mixing Acinetobacter sp., Pseudamine bacter granuli, Device and Streptomyces coelicola in an isovolumetric manner, and the synthetic flora is prepared by mixing Acinetobacter sp., Pseudamine bacter granuli, the Device and the Streptomyces coelicola in an isovolumetric manner. The synthetic flora disclosed by the invention has excellent environmental adaptability and ecological safety, can effectively break through the application bottlenecks of low colonization efficiency, poor functional stability and the like caused by regional difference of the existing microbial preparations, can realize stable colonization and efficient expression of drought resistance functions under different moisture conditions, and has wide application prospects. Therefore, the survivability of crops under drought stress is obviously improved.

Ceramic multilayer component, comprising: a component body (110) with spaced-apart side surfaces (112) and circumferentially extending surfaces (114) that connect the side surfaces (112) to each other; internal electrodes (120) which are arranged in the longitudinal direction of the component body (110) in the component body (110); outer electrodes (130) with a front section (131a) covering the side surfaces (112) and with a band section (131b) extending from the front section (131a) and covering sections of the circumferentially extending surfaces (114); and Crack guidance patterns (140) arranged in the component body (110) and guiding the growth direction of a crack that has been generated by the circumferentially extending surfaces (114), so that the crack (C) is directed in the direction of the side surface (112), the crack propagation pattern (140) comprises: a plate without broken sections as a first metal sample (142); and a second metal pattern (144) with several gaps (144a) at fixed intervals in the longitudinal direction, wherein the second metal pattern (144) is arranged such that it is closer to the circumferentially extending surface (114) compared to the first metal pattern (142).

The invention discloses a kind of functionalized water-based paint and preparation method thereof, belong to the technical field of water-based acrylic resin coating.The functionalized water-based paint includes 75.00-90.00 parts of water-based acrylic resin, 1.00-8.00 parts of alkyd resin, 2.00-8.00 parts of hexamethoxymethyl melamine and / or silane coupling agent, 1.00-3.00 parts of dipropylene glycol butyl ether, 1.00-3.00 parts of composite fungicide and 5.00-15.00 parts of water, wherein, the composite fungicide includes the organic mildew-proof agent of isothiazolinone class of specific proportion, iodopropynyl n-butyl carbamate, 4-bromo-2,5-dichlorophenol, 4-tolyl diiodomethyl sulfone, metconazole organic mildew-proof agent, surfactant, stabilizer, benzyl alcohol and water.The functionalized water-based paint of the present invention has excellent antibacterial and mildew-proof function, high stability, strong anti-loss property, strong weather resistance, can be used outdoors for a long time.

The invention belongs to the technical field of biology. The invention relates to an antioxidant composition, in particular to an antioxidant composition and application thereof in normal-temperature preservation of boar semen. Researches find that the activity of boar sperms in the normal-temperature preservation period can be effectively improved by independently adding lycopene or antioxidant SKQ1, the combined use effect of lycopene and antioxidant SKQ1 shows a synergistic effect, and when the boar sperms are preserved to the seventh day, the average sperm activity value exceeds 70%. In addition, through combined treatment, the integrity of sperm acrosome and plasma membrane is remarkably maintained, the antioxidant enzyme activity of sperms is improved, the active oxygen and malonaldehyde level are effectively reduced, meanwhile, the mitochondrial membrane potential and the adenosine triphosphate content are remarkably improved, and the expression level of sperm P-AMPK and Nrf2 protein is improved. In conclusion, the lycopene and the SKQ1 are combined for use, oxidative stress and energy metabolism are synergistically regulated and controlled, the quality and function stability of the boar sperms in the normal-temperature preservation process are remarkably improved, and the lycopene and the SKQ1 have good application value and application prospects.

The present invention relates to a waterproof and moisture-permeable sleeping bag fabric and a preparation method thereof, belonging to the technical field of functional fabrics. It is composed of a functional surface sizing and a base fabric. The prepolymer base glue and the crosslinking moisture-permeable auxiliary agent in the functional surface sizing crosslink and polymerize on the surface of the base fabric under the initiation of ultraviolet irradiation, enabling the base fabric and the coating layer to have good bonding ability. Moreover, the crosslinked structure is supported by the warp and weft cross-network of the base fabric, having better mechanical properties, not being easily peeled off or damaged during use and washing, and having good functional stability. The prepolymer base glue is a polyurethane linear polymer containing a silicon chain segment, having excellent water resistance. The crosslinking moisture-permeable auxiliary agent is an oligomer with a polyether chain as the main chain, having certain hydrophilicity. The crosslinking forms numerous hydrophilic pores, and gaseous water can be adsorbed and diffused by these hydrophilic pores, thereby achieving a good moisture-permeable effect. However, liquid water droplets are difficult to penetrate through these tiny hydrophilic pores due to the surface tension effect, thus having waterproof performance.

The invention relates to the technical field of biological medicine, in particular to a cell preservation composition beneficial to long-distance transport of cells and a preparation process and application of the cell preservation composition beneficial to long-distance transport of the cells. And high survival rate and functional stability of cells in long-distance transportation and short-term storage are realized.

The invention discloses a finite element model construction analysis method for osteoclavicular decompression, and particularly relates to the field of osteoclavicular decompression, which comprises the following steps: extracting preoperative functional magnetic resonance image and fiber imaging data, and establishing a functional area map containing activation area and fiber trend information; then, an anisotropic elastic tensor parameter set of each functional region is constructed according to the thickness and direction consistency of the cortex, the anisotropic elastic tensor parameter set is input into the finite element model, and a combined stress field with coupled functional modal response and structural stress is established; under the condition of setting a plurality of bone window configurations, performing simulation and spatial aggregation on the displacement gradient response of the functional region, and extracting a stability drift sensitive curved surface; and finally, on the basis of response characteristics of the sensitive area, performing structural offset quantitative evaluation on each decompression scheme, outputting a bone window configuration combination causing the minimum functional stability loss, and providing structural stability support for decompression path planning.

The invention discloses stable selenol and poly (selenourethane) thereof, preparation and recovery methods and application, selenol is stable micromolecules with at least two degrees of functionality, and poly (selenourethane) is prepared by directly participating in polymerization of selenol. The selenol overcomes the limitation that selenium-containing small molecules are unstable in the environment, and the polyselenourethane has rich and adjustable performance, is stable in structure, simple in preparation method, high in reaction speed, few in side reaction in the polymerization process, high in molecular weight, suitable in polydispersity coefficient and excellent in optical performance, and can be applied to the field of electronic devices. Good mechanical properties are achieved in room-temperature and low-temperature environments; meanwhile, the polyselenourethane has good thermal responsiveness and oxygen responsiveness, chemical recovery of selenol can be achieved under the simple heating condition, the polyselenourethane can be degraded by reacting with oxygen, active oxygen and the like in the service environment, meanwhile, selenium-containing components capable of being biologically utilized are released, and the selenium-containing components can be recycled. And a new opportunity is provided for development of organic selenium chemistry and selenium-containing polymers and internal and external application of organisms.

The application relates to the field of food / medicine auxiliary materials, and more particularly to a compound functional starch composition and a preparation method thereof. The compound functional starch composition is prepared from the following raw materials in mass parts: 65-100 parts of a compound starch matrix, 1-5 parts of a thickening agent, 3-6 parts of a water retention agent, 1-3 parts of a compatibility agent, 0.1-0.3 parts of an antioxidant, 3-5 parts of microcrystalline cellulose, 1-3 parts of citric acid, 0.5-1.5 parts of sodium trimetaphosphate, 3-6.5 parts of a functional anhydride and 180-250 parts of deionized water. The finally obtained compound functional starch composition not only has excellent functionality, but also has good storage stability, compatibility stability and freeze-thaw stability; the compound functional starch composition can improve the loading efficiency and has good processing application performance, thereby greatly improving the functionality and functional stability of the compound functional starch composition, expanding the applicable range of the compound functional starch composition in the field of food / medicine auxiliary materials and having very excellent application prospect.

This invention relates to the field of medical materials technology, and discloses a biodegradable medical gauze based on plant fibers and its production process. The medical gauze is made from raw materials comprising the following parts by weight: 5-15 parts plant fiber; 0.5-2.0 parts tannic acid; 0.1-1.0 parts boric acid; and 100 parts 1-allyl-3-methylimidazolium chloride. The production process includes: dissolving the above raw materials in an ionic liquid to form a homogeneous solution, coating it into a film, then performing a coagulation and regeneration treatment in an alcohol-water solution, controlling the residual amount of ionic liquid in the final product, and finally drying. This invention achieves long-term functional stability by controlling a portion of the residual ionic liquid as an internal plasticizer during the coagulation step, while simultaneously embedding the antibacterial component tannic acid within the cellulose matrix. This solves the problems of rigidity and easy detachment of functional components in traditional regenerated cellulose materials. The resulting gauze possesses biodegradability, flexibility, and long-lasting antibacterial properties.

The invention provides modified hydroxyapatite as well as a preparation method and application thereof. According to the invention, the hydroxyapatite is subjected to body modification, and the surface of the hydroxyapatite is modified with a structural unit containing 1, 4-dihydropyridine, so that the modified hydroxyapatite with anti-inflammatory and anti-oxidation characteristics is obtained, the functional stability and safety of the hydroxyapatite are improved, and the acting effect is prolonged; moreover, the modified hydroxyapatite with different numbers of modified structural units and different antioxidant effects can be obtained by controlling the proportion of the raw materials, and the obtained modified hydroxyapatite is processed into different forms for use according to actual application requirements.

The invention discloses a high-strength corrosion-resistant glass fiber reinforced plastic composite material and a preparation method thereof, and the high-strength corrosion-resistant glass fiber reinforced plastic composite material comprises the following raw materials in parts: 60-100 parts of a matrix, 20-50 parts of reinforcing fibers, 1-5 parts of a modifier, 1-5 parts of a reinforcer, 1-5 parts of a curing agent, 1-5 parts of a defoaming agent, 1-5 parts of a flatting agent, 1-5 parts of a flame retardant, 1-5 parts of an ultraviolet light absorber and 1-5 parts of a pigment, the matrix is specifically made of high-performance phenolic epoxy vinyl ester resin, the reinforcing fibers are specifically made of high-strength glass fiber cloth, the matrix, the reinforcing fibers and multiple functional auxiliaries are reasonably proportioned to form a synergistic enhancement effect, the mechanical strength and corrosion resistance of the glass fiber reinforced plastic composite material are remarkably improved, and the glass fiber reinforced plastic composite material is suitable for being used in the field of glass fiber reinforced plastics. The matrix provides stable chemical resistance and binding power, the reinforcing fibers endow high tensile strength and impact resistance, the modifier optimizes the interface bonding effect, and the reinforcement fills microdefects to improve compactness, so that the material keeps long-term structural integrity and functional stability in a severe environment.

The invention relates to the technical field of textile fabrics, in particular to a bio-based antibacterial and deodorant breathable fabric and a production method thereof. The fabric is obtained by spinning and weaving the following raw materials in parts by weight: 37-43 parts of Xinjiang long stapled cotton, 40-50 parts of lyocell fibers and 12-18 parts of functional nylon fibers; the preparation method of the functional nylon fiber comprises the following steps: adding the cool feeling-moisture absorption and sweat releasing composite functional master batch in the nylon stock solution stage, and adding the bio-based antibacterial agent OPHB in an amount which is 2-5% of that of the functional nylon fiber raw material. According to the invention, through precise proportioning of raw materials, integration of composite functions and collaborative optimization of a whole-flow process, composite function collaboration of antibacterial and odor-inhibiting, cool feeling, moisture absorption and sweat releasing of the fabric is realized, the core quality is improved, and meanwhile, the fabric has green and environment-friendly properties and long-acting stability of functions, is adaptive to multi-scene requirements, and is high in industrial feasibility.

The application discloses a modified polypropylene material and a preparation method thereof, and belongs to the technical field of polypropylene materials. According to weight parts, the modified polypropylene material comprises the following raw materials: 100 parts of polypropylene resin, 30-40 parts of maleic anhydride grafted polypropylene, 25-35 parts of nano calcium carbonate, 10-14 parts of additives and 2-3 parts of silane coupling agent. The raw materials are mixed in a high-speed mixer according to the proportion, discharged and cooled, and then sent into a double-screw extruder to be melt-extruded, cooled and granulated, so that the modified polypropylene material is prepared. The polypropylene is modified by using the synthetic additives, so that the modified polypropylene material has the modification effects of flame retardation, aging resistance and mechanical strength, and the additives themselves have chemical bond effects with the polypropylene matrix, so that the defects of migration resistance and bleeding resistance of the functional components are effectively improved, and the functional stability and durability of the modified polypropylene material are improved.

The embodiment of the invention relates to the technical field of medical coating materials, in particular to a bioprosthetic valve coating and a method for forming the coating on a bioprosthetic valve. The bioprosthetic valve coating provided by the embodiment of the invention comprises a polylactic acid-glycolic acid copolymer loaded with curcumin and curcumin nanoparticles, a platelet inhibitor, a piezoelectric nanofiber membrane and hydrogel of methylacryloyl gelatin-methylacryloyl heparin (GelMA-HepMA). According to the bioprosthetic valve coating provided by the embodiment of the invention, the bioprosthetic valve can have the comprehensive performance of resisting thrombus in the early stage of implantation, resisting inflammation and oxidation in the middle stage and delaying calcification and degeneration of valve leaflets in the long term, meanwhile, endothelialization of the bioprosthetic valve is promoted, and the long-term functional stability and biocompatibility of the bioprosthetic valve are improved.