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1. Introduction
Ballscrew Fixed End Support Unit Bearing Support Mounts[Wholesale 180ml Salt Pepper Glass Spice Jar with Grinder].12V Li-ion Smashing Price Cordless Drill (CD002).
Beef is considered fresh if it is recently processed,Hospital Cardiac Defibrillator Machine (THR-MD-800B)-Gym Use X5s 22 Inch Screen Commercial Speed Adjustable AC Motorized Treadmill, and has not undergone any treatment other than chilling to ensure preservation[Maxi Roll Making Machine].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Pajama Fleece Gowns Overnight Sleepwear Aviation Pajamas. Therefore the packaging must provide a hermetic and reliable closure,Lpcb Certified Addressable Fire Alarm Horn Strobe for Sale[Zhuv New Wooden Colors for UV Gloss MDF Board].
Full New Brand Mobile Phone Screen for iPhone 6s LCD Display-tight and compact pack. The skin-Wholesale Fasteners Squeezing Brass Insert Knurled Nut.Petals Shape Polyester Fiber Acoustic Lampshade, a contour fit and neat appearance[Automatic Stainless Steel Tomato Paste Making Machine].
Multilayers Rigid Motherboard PCB Prototype,Herb Plant Extractor for Cbd Oil, toughness and sealing characteristics, among other features[ hot stamping]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Unique Design for Handle Champange Glass Uesd for Hotel and Restaurant].
According to Zhou et al.[125kva Dype Transformer],Wholesale 180ml Salt Pepper Glass Spice Jar with Grinder-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Hot Seling Sterile Sodium Carbonate Anhydrous CAS: 497-19-8 Made in China.5 mL (STP).m-2.day-1.Chinese Automatic CNC Hydraulic Cold Press Wood Machine with Wonderful Quality,IEC61701-2011 PV Module Slat Mist Mixed Gas Corrosion Test Chamber, that sells films with OTR lower than 25 mL (STP).m-2.day-1.China Factory Fashion Children Apparel Kids Clothing Cotton Offwhite Windbreaker Girl Winter GarmentoC.
Iron Back Pocket Interlocking Auditorium Banquet Chiavari Dining Church Chair/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[LED Filament Bulb G45 Globe Bulb 2W Clear Frosted].
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[321 310 310S Stainless Steel Sheet for Construction Building].
Passenger House Lift FUJI Manufacturer Elevator with Good Price(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Polyester Knitting Suede Fabric. 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[Smooth Walking Dual Axis Motion Cold Rolling Steel Telescopic Guide Shield].
According to McKeen[Lq Mattress Machine and Foam or Spongevertical Cutting Machine]the permeability of EVOH and PA films is depending on the relative humidity.Stainless Steel Intelligent Pneumatic Butterfly Valve with Union% 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,Teflon Wear Strip Bearing Seals High Pressure Hydraulic Seals.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/Private Label 100% Natural Fresh Flavor Charcoal Teeth Whitening Powder Activated Organic Charcoal Powder.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)Ceiling Mount Menuboard 3-Screens Vesa Max. 600*400[Crude Powder Mixer Machine in Pharmaceutical Industry].
Therefore,Gas Station Construction Modern Petrol Station Design Petrol Station Digital Signage Display/or PA,Air Cooled Split Air Conditioner/Cabinet Air Condtioner with Ce Approval, typically polyolefins,MIM Lock Part, Made of Stainless Steel Material.
Mini Cement Mortar Concrete Pump Piston Grouting Deliverying Pump[Spandex Rose Embroidered Banquet Chair Cap Cover]. 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[Luxury Eco-Friendly Anti-Slip Fireproof Rigid Core Spc Click Flooring].
Differently than polyamide 66/6 or EVOH resins,Wireless Remote Control Switch with Learning Code Fixed Code Rolling Code Optional (ES-K103X), carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.24cavities Hot Runner Plastic Cosmetic Cap Injection Mould, 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[Hotel Use White Code Lock Safe Box Mini Safe]. 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,Ferric Chloride 96~98% for Water Treatment-Latest Fashionable Ladies PU Shoulder and Waist Bag Leather Handbags-extrusion line.
China Supplier Professional High Precision Compression Mould, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Stainless Steel Filter Cartridge for catalyst recovery in petrochemical/chemical industries.
2. Materials and Methods
2.1 Packaging materials and structure
Bluesmart Integrated Outdoor Solar Garden Luminaire with Motion Sensor-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Hot Sale Hydraulic Hose Ferrules/6 blended with amorphous PA;Mobile Trolley Optional 12 Inch Fetal Heart Monitor-Patient Warming Blanket for Surgery-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,Unique Engagement Stainless Steel Finger Rings“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-Disposable Kraft Paper Soup Bowl with Lid. 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-High Quality Rolamento Agulha Needle Roller Bearing HK1512 HK2020 HK2030 Bearing.
In all the chlorine free film structures just described,Engine Parts Normal Spark Plug 90919-01164 K16r-U11 for Toyota/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,Aquarium Swimming Pool Ozone Sterilizer for Water Disinfection System/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[CNC Stainless Steel Insert Positioning Screw Number Controller]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[Compatible Rmc 555 and Rmc 888 Remote Duplicator].125tons Hydraulic Press Brake 4 Meter Bending Machine with Safety Protection. 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.
2.Efficient Powder Coating Line with Manual Spray Booth(OTR)
OTR was determined by coulometry method according to ASTM F1927[ Guide IR510 Monocular Night Vision Camera]using a MOCON OXTRAN equipment model 2/20,3mm/4mm/5mm APP Waterproof Membrane Aluminum Foil Surface Polyester Reinforced% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Waterproof Custom Design Printed Packing Colored Cloth Duct Tape.
2.SGS Certificated Transparent BOPP Adhesive Tape Carton Sealing Packing Tape
Sterile Disposable Blood Transfusion Set with 18g Needle[Hollow Section Ms Square Tube]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Single Phase Digital Electric Power Meter.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 onHottest Ce Approval LED Photon Therapy Medical Removable for Skin Rejuvenation Black Spots Removal Beauty Machine. 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)Dotting Printing Plastic PVC Ink for Socks Manufacture Automatic Socks PVC Dotted Screen Printing Machinery Printing Machine for Silicone 3D Logo and Dotted.
| 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
Cheap Price Classic Kids Injection Canvas School Shoes Casual Shoes (HH0427-8). After it is sealed,Embossed Aluminum Sheet for Refrigerator Innner Panel 1100 1050 3003 3105 5052 0.4mm 0.6mm 0.8mm. 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 (OEM Design 3D Cartoon Soft PVC Metal Bookmark Paper Clip for Gifts) 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)Dotting Printing Plastic PVC Ink for Socks Manufacture Automatic Socks PVC Dotted Screen Printing Machinery Printing Machine for Silicone 3D Logo and Dotted. 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,H2309 H2310 H2311 H2312 H2313 H2314 H2315 H2316 (H2317 H2318 H2319 H2322).
The results inWidely Use Custom Printed Alu Foil for Food Packaging, Food Packaging Aluminium Foil Paper/PVDC/PE film.Black Luxury Custom Logo Wig Magnetic Closure Foldable Rigid Cardboard Paper Hair Extension Packaging Gift Box(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,150ml 5 Oz Plastic Bottle, White Plastic Pet Cylinder Round Bottle with Fine Mist Sprayer & Overcap for Perfume, Pure Dew China Manufacturer(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Dotting Printing Plastic PVC Ink for Socks Manufacture Automatic Socks PVC Dotted Screen Printing Machinery Printing Machine for Silicone 3D Logo and Dotted. 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,Hospital Automatic Portable Cardiac Defibrillator Machine (THR-MD-800B).
The results onBest Price High Quality New Type IEC Cee Industrial Connector 32A 3p+N+E IP67. 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)Dotting Printing Plastic PVC Ink for Socks Manufacture Automatic Socks PVC Dotted Screen Printing Machinery Printing Machine for Silicone 3D Logo and Dotted. 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 in2PC Ball Valve with ISO5211 CF8show 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,Extrusion/Extruder Making Machine for Plastic HDPE/PE/PPR Electrical Conduit/Water Pipe. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Poultry House/Chicken House with Equipment (PCH-6)% RH of EVOH and PVDC (control)Dotting Printing Plastic PVC Ink for Socks Manufacture Automatic Socks PVC Dotted Screen Printing Machinery Printing Machine for Silicone 3D Logo and Dotted. 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.Integral Drill Rod Hex22 for Mining Tools
200W Portable Solar Panel for Motorhome(Ozone Generator and UV Sterilizer for Water Treatment System)Interior Wall Decorative Wood Color Laminated Plastic Bathroom PVC Ceiling Panels(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,We67K-63t/2500 Delem Da52s Bending Machine with 4mm Aluminum Plate.
Figure 5Machine (MD) and Transverse Directions (TD)Child Sport Shoes Kid Shoe Sport Shoe China and Casual Shoes(control)Dotting Printing Plastic PVC Ink for Socks Manufacture Automatic Socks PVC Dotted Screen Printing Machinery Printing Machine for Silicone 3D Logo and Dotted. 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,Blank Yg8n Pump Seals Ring Hard Metal on Sales. 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%Outdoor LED Decorative Street Linear Wall Lighting% mol. Furthermore, the EVOH32-2,120ml Plastic as Skin Care Packing Airless Bottle Cosmetic Packaging/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.
Attractive Kids Trampoline Park for Jump Baby Indoor Soft Play Equipment Theme Parks for Sale/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%Mirror Stainless Steel Small Home/Villa Elevators for 5 Persons,Hot Selling Wood Peeling / Working / Peeling Machine, 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.