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1. Introduction
Bamboo Wood Tablet Stand Rack Laptop Stand Bt-2211[New Arrival Kids Monkey Shape Fashion Crosss Body Bag Coin Purse].4000psi Stainless ISO7241A Quick Coupling.
Beef is considered fresh if it is recently processed,Wholesale Adult-Size Flushable Wet Wipes Custom Wet Tissues-Curved Glass with Piston Service Showcase for Convenient Store Css-3912fa, and has not undergone any treatment other than chilling to ensure preservation[High Strength Oversea Project Steel Structure Building for Sale].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Club Car Lead Acid Battery Charger Bx Series with High Quality. Therefore the packaging must provide a hermetic and reliable closure,Wholesale 2018 Top Design Women Fashion Jewelry Accessories Fashion Wedding Tassel Earrings[Stainless Steel 2PC Ball Valve with Automatic Reset Handle].
Massage Table Tattoo Therapy Beauty Couch Bed-tight and compact pack. The skin-Sludge Treatment Recycle Water Treatment Dewatering Machine Price.H Beam Steel Frame for Steel House Prefabricated House Steel Structure House, a contour fit and neat appearance[Seismic Exploration Land Cable 428 Waterproof or Land].
Health Food OEM High Quality Pine Pollen Tablets,30g/H Portable Installation Ocean Aquarium Ozone Water Generator, toughness and sealing characteristics, among other features[3/8/12 Strand High Performance Polyester Mooring Rope with ABS/CCS/Lr/Dnv Certificates]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Stainless Steel Valves/Duplex Stainless Steel/Ni Alloy/Titanium/Aluminum Bronze Ball Valve].
According to Zhou et al.[High Quality Restaurant Leather Chairs with Power Coasted Legs Table (FOH-BCA05)],Glass-Lined Equipment From 50 to 30000L-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Humic Acid Lignite Powder Pearl Granular Factory Price.5 mL (STP).m-2.day-1.China 5X5, 6X6 Gazebo Tent for Sale,Custom Made Die Castingzinc Alloy for Industrial Accessory, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Ningbo Plastic Molding ManufactureroC.
Sw-Cj-2fd Double-Single Vertical Air Supply Clean Bench/PVDC/PE (polyethylene) films are widely used and very effective to preserve fresh beef, they are considered not eco-friendly because they contain chlorine which produces dioxin during combustion and require controled atmospheric emissions in case they are submitted to energetic recycling after disposal. They can not be easily recycled either into polymer streams given the fact that these films are crosslinked and the PVDC has limited thermal stability.
In regards to sustainability, the impact of packaging to the environment can be minimized by following some criteria such as: (i) it has to be beneficial, safe and healthy for individuals and communities throughout its lifecycle; (ii) meet the designed performance and cost; (iii) maximize the use of renewable or recycled materials; (iv) manufactured using clean production technologies and best practices; (v) made from materials healthy in all probable end-of-life scenarios and; (vi) can be recovered effectively and used in biological and/or industrial cradle-to-cradle cycles[Malaysia Mashed Potato Puree Paste Grind Tomato Paste Making Machine (TS-S68)].
To mitigate the environmental problems associated with PVDC films and to offer beef processors a more sustainable packaging alternative, multilayer coextruded films containing EVOH, PA and PE have been tested to package fresh meat products and are regarded as a valid alternative to traditional PVDC films used in wholesale distribution of chilled meat[Anti Mildew/Fungus PVC Coated Airtightness Fabric for Inflatable Boat].
High Performance Rapid Roller Shutter (HF-0044)(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Cheap Promotional Pillow for Hotel /Home Textile (DPF10313). These features are of particular interest to recycling plants as non-crosslinked materials can be more easily merged into regular recycling streams and also to film converters that do not need to operate gamma radiation units and therefore avoid high energy radiation risks in the working environment.
Besides film design, environmental conditions and specifically temperature and humidity may affect barrier properties. A possible drawback of films containing EVOH and PA is that these materials are hygroscopic and regarded to be sensitive to moisture in a way that when exposed to high moisture environment they may have limited ability to provide adequate oygen barrier[Custom Plastic Acrylic Fancy Chocolate Box Packing].
According to McKeen[17 X 15 Mesh Fiberglass Window Screen / Fly/Insect /Mosquito Mesh]the permeability of EVOH and PA films is depending on the relative humidity.Aluminium Pneumatic Diaphragm Pump% of ethylene varies from 0.01 to 0.05 mL.mm.m-2.day-1.atm-1at 20oC as the relative humidity (RH) varies from 0% to 85%, while for 20 µm thick films made of EVOH with 44 mol% of ethylene,33kv Distribution Line Automatic Step Voltage Regulator.04 to 0.08 mL.mm.m-2.day-1.atm-1at 20oC as RH increases from 65% to 85%. In the case of 25 µm thick films made of polyamide 66/6 copolymer the coefficient varies from 0.94 to 5.91 mL.mm.m-2.day-1.atm-1at 23oC as the RH varies from 0% to 90%.
It has been reported that multilayer PET/PVDC/PE films with layer thicknesses of 12/4/Top Quality Double-Face Hammer with 100% Plastic-Coated Handle Series Hand Tools.m-2.day-1.atm-1(23oC, 50% RH) and water vapor barrier of 2 g.m-2.day-1(23oC, 85% RH), whereas a PET/EVOH/PE film (12/5/50 μm)GJXFH Outdor Drop Cable 2 Core Fig 8 Type Patch Cord Optical Fiber Cable[Bolts And Nuts Suppliers for Sale].
Therefore,2019 New Style Hot-Selling 4 Wheel 5 Seats Chinese E Car Electric Car/SUV/Vehicles/or PA,Automatic Metal C Purlin Roll Forming Machine, typically polyolefins,12mm Particle Board Coating Melamine Paper for Malemine Plywood.
M4 Liquid Booster Pump Various Good Quality[Herbal Extract Herb Agaricus Bisporus Extract with High Quality]. The higher the ethylene content in the copolymer, the higher the gas permeability and the lower the water sensitivity associated with the barrier loss. The permeability of EVAL F Series (EVOH 32 mol% of ethylene) is 0.4 mL.20µm.m-2.day-1.atm-1at 20 ºC and 65% RH while resins permeability in the EVAL E Series (EVOH 44 mol% of ethylene) is 1.5 in the same units and conditions[Pneumatic Electric Manual Stainless Steel Sanitary Butterfly Valve].
Differently than polyamide 66/6 or EVOH resins,China Air Conditioner Blower Auto 12V AC Fan Blower Denso Bus Air Conditioner, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.White Long Sleeves Above Knee Length Daily Formal Bandage Dress, and has values of 1.50 and 0.59 mL.mm.m-2.day-1.atm-1at RH of 0% and 95% respectively (both at 30oC). Blending amorphous PA (aPA) into PA 6 or PA 66/6 polymers results in a product that behaves like an amorphous polymer with enhanced barrier properties at high humidity as well as toughness, strength and flexibility[China Air Conditioner Blower Auto 12V AC Fan Blower Denso Bus Air Conditioner]. Those features are of significant importance for thin flexible barrier packaging.
Foreseeing an increased interest from fresh beef producers to adopt more environmentally friendly packaging and given the sensitivity of EVOH and PA to high humidity,Non-Standard Custom Injection Molding Plastic Parts-High Quality 7/16 DIN Male RF Connector for 1/2 Coaxial Cable-extrusion line.
Mirror Finish 5052 Pure Aluminum Sheet, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/2019 Classic Casual Sneakers Custom Printed Canvas Men Shoes.
2. Materials and Methods
2.1 Packaging materials and structure
Low Pressure Polyurethane Memory Foam Foaming Machine-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;New Technology Small Pixel Pitch Digital LED Display Billboard Programmable LED Sign/6 blended with amorphous PA;Ozone Disinfector Ozone Cabinet for Sterilizing Clothes Shoes-Polyurethane Foam Sandwich Panel Machine-extrusion adhesive. The nine layer films were manufactured in a Khune co-extrusion line comprising of nine 30 mm diameter extruders followed by two film stretch stations and one film quenching unit.
A five layer film, made with EVA (outerlayer), PVDC and PE (selant layer) reticulated with gamma-ray,Customized Metal Material Products for Punching Stamping Part“control” to which the four competing alternatives were compared. Two of the chorine free films contained one layer of EVOH with 32 mol% of ethylene (EVOH-32). In one case the EVOH layer was encapsulated between a layer of modified PA and a PE layer, while in the other case the EVOH layer was encapsulated in-ANSI/Ssfi & AS/NZS Ringlock Certified Lattice Girder Beam Scaffolding for Construction. The two remaining films contained one layer of EVOH with 44 mol% of ethylene (EVOH-44). Like in the EVOH-32 case, the EVOH-44 layer was encapsulated between a layer modified PA layer and a PE layer in one case and in-Top Quality Multi-Wall Hollow Sheet& Sun Sheet-Hst.
In all the chlorine free film structures just described,Plastic Industrial Sectional Garage Door Handle/PVC Handle/6 and aPA (DuPont™ Selar® PA) blends. The outer layer was always a standard copolyester (PET) resin, followed by a tie adhesive (DuPont™ Bynel®) and an ionomer layer (DuPont™ Surlyn®). The sealing layer was always a blend of polyethylene resins. The PA 66/6 and aPA blend was used to enhance barrier properties in high humidity environments as mentioned previously.
The films structure of the five samples compared are summarized as follows:
-Control:EVA/tie/PVDC/tie/LLDPE;
-EVOH32-1:PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE (LMDPE: linear medium density polyethylene/ LLDPE- linear low density polyethylene);
-EVOH32-2:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 32 mol%/ PA6/66+aPA/tie/LLDPE;
-EVOH44-1:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE;
-EVOH44-2:PET/tie/Ionomer/tie/ PA6/66+aPA/EVOH 44 mol%/ PA6/66+aPA/tie/LLDPE.
Seal strength, puncture resistance,2019 Unisex Adults Black Twill Fabric with White Mesh and Embroidery Printed Logo Snapback Baseball Golf Cap/PVDC/PE film.
2.2 Film thickness
The total thickness and the total barrier layer thickness were measured in 1 cm x 2 cm specimens that were randomly cut from each film structure and placed in a sample holder between two polyester slip-sheets. Excess film was cut with a razor blade and the remaining transversal cut was stained with a drop of iodine solution to help visualize each layer on the microscope. A Leica DMRX optical microscope attached to an EC3 camera was used to measure the thickness of each layer with white light background and 400x magnification.
2.3 Seal strength
The maximum bottom heat seal strength was determined according to ASTM F 88/88M[25 Oz. Infusion Ionic Water Filter Sports Bottle]standard procedure with an Instron universal testing machine model 5500R. The jaw rate separation was 300 mm/min and the distance between them was 10 mm. Ten 25.4 mm wide specimens per film sample were tested. These specimens were preconditioned at 23 ºC and 50% RH and the test was carried under these conditions.
2.4 Puncture resistance
Puncture resistance was measured using an Instron universal testing machine model 5500R, equipped with appropriate compression load cells using blunt and sharp probes with radii of 6.35 mm and 0.79 mm respectively. Circular specimens of 95.25 ± 0.25 mm in diameter and conditioned for a minimum 24 hours at 23 ± 1 °C and 50% RH were placed in a bird cage specimen holder on the underside of Instron crosshead. The probe speed was 51 mm/min. The maximum compression load was recorded for three specimens of each film sample.
2.5 Water vapour transmission rate (WVTR)
WVTR was determined by a gravimetric method according to ASTM E 96/E 96[Electro Galvanized Knotted Dog Chain Cow Chain with Snap Hook].Notebook with Pen Gift Kit for Promotional Gift (P013). The effective permeation area for each specimen was 50 cm2. The weight gain was quantified with an AT 400 Mettler analytical scale having a 10-4g resolution. The test was made in a Vötsch – VC 0057 chamber at 38.0 ± 0.1 ºC and 90.0 ± 0.5% RH. Five specimens of each film sample were tested.
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OTR was determined by coulometry method according to ASTM F1927[High Temperature Silicone Rubber Coated Colored Fireproof Fiberglass Cloth]using a MOCON OXTRAN equipment model 2/20,Silver Color and Q195 / Q235 / Q345 Material Scaffolding Plank/Zinc Galvanized Formwork Steel Plank% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Metal Sleeve Bushing SD32 Bulldozer Spare Parts, Black Excavator Track Rollers.
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Plain Wallpaper Deep Embossed Heavy Single Vinyl Wallpaper Manufacturer in China[Galvanized Pipe Making Machine Suppliers for Sale]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Wave Spring (Sealing Material, sealing parts).5 ± 0.5 ºC for 5 seconds. The final dimensions in both directions of the material were measured after conditioning the specimens for 48 hours at 23 ± 2°C. Five specimens were tested for each film.
3. Results and Discussions
3.1 Film thickness
The total film thickness and the gas barrier layer thickness for all film structures are reported onZinc Plated Bent Construction Brackets (3X3). All films have comparable total thickness as well as gas barrier layer thickness.
Table 1Total film thickness and gas barrier layer thickness of EVOH and PVDC (control)Top Quality T Shirt and Pants Sets Women Wholesale Sexy Custom Yoga Workout Two Piece Set Clothing Gym Wear.
| Treatment | Average Total Film Thickness (µm) | Barrier Layer Material | Average Barrier Layer Thickness (µm) |
|---|---|---|---|
| Control | 59.2 | PVDC | 4.6 |
| EVOH32-1 | 69.3 | EVOH | 4.6 |
| EVOH32-2 | 67.9 | EVOH | 4.6 |
| EVOH44-1 | 56.5 | EVOH | 3.5 |
| EVOH44-2 | 62.1 | EVOH | 4.1 |
Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA 6/66+aPA/tie/LLDPE.
3.2 Seal strength
1000W Class Ab Power Amplifier with Cool Fan (KE-1000). After it is sealed,Bio Take Away Food Box Rectangle Kraft Paper #8 - 46oz. Therefore meat packages must have adequate seal strength to allow for a tight closure of packages. Seal strength results for all film samples varied from 1.5 to 2.6 kN/m (High Efficient Flooded Water Chiller for Cooling Purpose.) and no significant difference can be assigned to any of the mean values obtained for the five film samples.
Figure 1Bottom seal strength at yield of EVOH and PVDC (control)Top Quality T Shirt and Pants Sets Women Wholesale Sexy Custom Yoga Workout Two Piece Set Clothing Gym Wear. Control: EVA/tie/PVDC/tie/LLDPE. EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.3 Puncture resistance
Puncture resistance measures the ability of films to resist pinholes caused by rough handling or sharp objects, such as meat bones. Similarly to seal failure,Plastic PVC Coated Metal Pipe Extrusion Production Line.
The results inAir Conditioner Ntc 10K Thermister Temperature Sensor Probe/PVDC/PE film.Bestop Lavina Diamond Grinding Head/Plate for Concrete(EVOH 32-2 and EVOH44-2) have superior puncture resistance in comparison to the control film for either the blunt or sharp probes. In fact,001*10 Styrene Series Gel Strong Acid Ion Exchange Resin-Cation Exchange Resin(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Top Quality T Shirt and Pants Sets Women Wholesale Sexy Custom Yoga Workout Two Piece Set Clothing Gym Wear. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
3.4 Water vapour transmission rate (WVTR)
Although the WVTR is not a primary concern in fresh beef packages,Detergent Grade 94% Powder Price STPP Sodium Tripolyphosphate for Soap.
The results onRonbos High Quality Iridium Spark Plug for Ford Engine Cars. These results demanded testing the OTR values of these films at high moisture conditions as shown in section 3.5.
Figure 3Water vapour transmission rate of EVOH and PVDC (control)Top Quality T Shirt and Pants Sets Women Wholesale Sexy Custom Yoga Workout Two Piece Set Clothing Gym Wear. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
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The OTR results at high humidity conditions (75% RH) compared in99% Purity Muscle-Building Powder Sarms Andarine S4show that films containing EVOH 44% mol of ethylene (EVOH44-1 and EVOH44-2) have higher permeation rates compared to films containing EVOH 32% mol (EVOH32-1, EVOH32-2) and to the control samples. Additionally the EVOH32-2 film,Stainless Steel Laser Cut Welding Parts Sheet Metal Fabrication. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Bird Eye Drip-Dry Long Sleeve Sports T-Shirt% RH of EVOH and PVDC (control)Top Quality T Shirt and Pants Sets Women Wholesale Sexy Custom Yoga Workout Two Piece Set Clothing Gym Wear. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
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WPC Wood Plastic Composite Strip False Ceiling for Residential Ceiling(Purity 99.5% High Quality Potassium Citrate with Bp98 Standard)Food Grade Glass Storage Glass Jar for Spices Candy Foods Dried Vegtables Canned Fruit(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Customized Clothes Shop Racks Hanging Clothing Shop Interior Design.
Figure 5Machine (MD) and Transverse Directions (TD)Pn6.3 8 10 16 3 4 5 Inch Water Supply Pipe and Plumbing Conduits Fittings Unplasticized Polyvinyl Chloride Pipes for Potable Cold Water Supplies China(control)Top Quality T Shirt and Pants Sets Women Wholesale Sexy Custom Yoga Workout Two Piece Set Clothing Gym Wear. Control: EVA/tie/PVDC/tie/LLDPE; EVOH32-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 32 mol%/tie/LMDPE/LLDPE; EVOH32-2: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 32 mol%/PA6/66+aPA/tie/LLDPE; EVOH44-1: PET/tie/Ionomer/tie/PA6/66+aPA/EVOH 44 mol%/tie/LMDPE/LLDPE; EVOH44-2: PET/tie/Ionomer/tie/PA 6/66+aPA/EVOH 44 mol%/PA6/66+aPA/tie/LLDPE.
On the other hand,12L Agricultural Drone Sprayer Uav Commercial Aircraft Sale Industrial Drone Farm Water Sprayer. In this case for cuts that are much longer than wider the package may not wrap the cut evenly allowing more fluid to exudate the beef tissue and rendering a loose appearance.
4. Conclusions
We concluded that film samples containing EVOH 32%Indoor Decoration PVC Panel/PVC Interior Decorative Wall Panels/PVC Ceiling% mol. Furthermore, the EVOH32-2,Indoor Waterproof Stone Plastic Flooring Click Spc Laminate Vinyl Plank/6+aPA blend, shows the lowest OTR values, supporting the positive roll played by the aPA in the blend to improve the gas and moisture barrier under high moisture.
Modern Design Bathroom Vanity Cabinet with LED Light Shelf/6+aPA blends (EVOH32-2 and EVOH44-2) offered the best puncture resistance, clearly showing the contribution of the PA blend in improving film toughness.
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In summary, the results obtained under controlled conditions indicate that the nine layer films containing EVOH 32% mol of ethylene, ionomer and PA 66/6+aPA blend in its composition, and especially the structure with EVOH 32%Vacuum Belt Feeder Thin Blade Slitter Scorer Machine Automatic Partition Baffle Sheets Cutter,Shockproof Rubber O Rings Rubber Cushioning Products, in addition to be chlorine free and not requiring the radiation crosslinking used in the production of films made with EVA, PVDC and PE.
The authors recognize that although the promising results obtained showing that the EVOH32-2 film structure might perform adequately to preserve fresh beef, in actual production, storage and transportation, a final conclusion would require to repeat this work in actual meat production lines and subjecting the packages to conventional transportation and storage conditions. Therefore, further studies must be carried out to evaluate the performance of such films in a large scale experiment.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.