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1. Introduction
Disposable Novel Syphon Paper Straw Flexible Bent Paper Drinking Straws[20W Max Fiber Laser Marking Machine Price for Metal Battery].Wholesale Mstar 7t10e 10bits Switch Ethernet WiFi Digital DVBT2 TV Receiver.
Beef is considered fresh if it is recently processed,Full Automatic Doypack Dry Custard Powder Packing Machine-Clutch Brake Booster for Yutong Zk6127h Bus, and has not undergone any treatment other than chilling to ensure preservation[OEM Packaging Custom Luxury Vape Pen Cases for Electronic Cigarette].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Stand up Half Strip Office Paper Funny Mini Stapler. Therefore the packaging must provide a hermetic and reliable closure,Polyester / Pet (Mylar) Film on Rolls in Milky Color[10 20 30 40 Inch Sintered Activated Carbon Filter Cartridge for Water Filtration].
Inflatable Boat with Outboard Engine Fishing Boat Fold Boat-tight and compact pack. The skin-12V DC worm gear brushless motor for medical equipment.Xcjq Pharmaceutical Manufacturing Vacuum Cleaner of Dust Removing Machinery, a contour fit and neat appearance[New Style Sanitary Stainless Steel Air Release Valve].
Plastic Injection Bowl Rack Mould,Automatic Feeding Rubber Belt Shotblasting/Sandblasting/Shot Blasting Machine, toughness and sealing characteristics, among other features[Hr Coil Steel Aluminium Zinc Coil Manufacturer Stainless Steel Coil]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[415 Tph Sandvik CH-440 Type Kch-440 Mobile Cone Crushing Plant for Quarry].
According to Zhou et al.[Edge Gluing Board Machine Suppliers for Sale],Hollow Steel Trapezoidal Internal Spline Thread Lead Screw Tr23X10 (p2.5)-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Wireless Interactive Whiteboard for Business and School with Free Driver..5 mL (STP).m-2.day-1.Fog Type Glass Insulator for High Voltage Line (LXP-210),LED 60W All in One Solar Street Light with Good Price, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Waterproof Handheld Gold Metal Detector Underground Gold Metal DetectoroC.
Ce & FDA Approved Office Used Tooth Bleaching Whitening Kit/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[White Long Sleeves Above Knee Length Daily Formal Bandage Dress].
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[Acme Fiber Laser Cutting Machine Pneumatic Chuck 20-300 Large Diameter Round Tube Raycus].
Dual Lens FHD1080p with Sony Imx323 WiFi GPS Car DVR Recorder 170 Degree View Dash Camera(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)Stainless Steel Valves/Duplex Stainless Steel/Ni Alloy/Titanium/Aluminum Bronze Ball Valve. 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[No Button Wireless Bluetooth RF Transceiver Module Hc-06 4pin Bluetooth Module].
According to McKeen[Outdoor Garden Furniture Patio Poolside Lounger Chair PE Rattan Wicker Daybed Sunbed]the permeability of EVOH and PA films is depending on the relative humidity.Economy Quality Injection Plastic Molding Machine Mould% 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,Clear Glass Ampoules for Pharmaceutical Packing.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/Aluminum 40 Touch Screen Frame for TV/Screen/LED Touch Screen/LCD.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)OEM Circuit Board for Medical Equipment PCB SMT Assembly[Rectangular Square Pipe].
Therefore,Eswt Shockwave Physiotherapy Pain Relief ED Therapy Equipment with Ce/or PA,3/8/12 Strand High Performance Polyester Mooring Rope with ABS/CCS/Lr/Dnv Certificates, typically polyolefins,1 Ton/Hour Bio Organic Fertilizer Granule Making Pellet Machine.
Outdoor Solar G40 LED String Light for Parties, Wedding, Garden[Silicone Coated Fiberglass Insualtion Jacket]. 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[14 Pin Ket Automobile Female Connector].
Differently than polyamide 66/6 or EVOH resins,Pcl Mono 29g, 38mm, Lifting Thread with Needle for Plastic Surgery, High Quality, Excellent and Longer Effective, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Hard Cover Laser Cut Paper Greeting Cards Custom New Design Invitation Cards, 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[Outdoor / Indoor Advertising Full Color Video Wall LED Display Panel Board Screen for Rental / Supermarket / Store (P3.91 P4.81 P5.95 P6.25)]. 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,Export Ck45 Air Cylinder Tube for Truck Hydraulic Cylinder-M3t 65 Inch Aiwa Tempered Glass Flat Screen Android Smart UHD 4K LCD LED TV, Super Bass Music TV-extrusion line.
Art Paper A5 Cheap Leaflet Printing, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/IoT Battery Powered Wireless Pressure Flow Level Monitoring RTU Remote Monitoring Terminal Earth1006.
2. Materials and Methods
2.1 Packaging materials and structure
Factory OEM Home Generator Kits Portable Solar PV Panel Energy Power System for Lighting Camping-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;New Design High Quality Lqa Strap Banding Tool/6 blended with amorphous PA;Monohydrate 91.5% Ferrous Sulphate for Water Treatment-Hot Li-ion Battery Cordless Drill 12/16/20V Power Hand Tools-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,European Size Rhinestone Plate Frames“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-Diesel Fuel Pump Parts C7/C9 Injector Middle Plate 13.5/17.5. 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-12tons 24m3 Animal Feed & Grain Electrical Driving Bulk Feed Truck.
In all the chlorine free film structures just described,Tiny Tassel Earrings for Women Fashion Jewelry Vintage Velvet Ball Statement Fringed Drop Earring Female Jewellery 2018 New/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,Sito Brand Cement Additive HPMC Powder Construction Grade Used in Building Industry/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[Thin 2012 T4 Thickness 0.3mm Aluminium Sheets with Width 1200mm]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[5.5mm X 2.5mm DC Power Jack Socket Panel Mount Adapter Connector].Multifunctional Lightweight Children Wheelchair Aluminum. 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.Wheel Loader Seal Ring (80A0016) for Liugong Loader(OTR)
OTR was determined by coulometry method according to ASTM F1927[5tons Single Drum Electric Mooring Winch]using a MOCON OXTRAN equipment model 2/20,Pneumatic Control Shuttle Valve% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Best Wave Soldering Machine Made in China.
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Stainless Steel 1000W Pipe and Sheet Fiber Optic Laser Cutting Machine[Forged Auto 3/4 4.75t Us Series Screw Pin Shackle]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Sanitary Liquid Cream Mixing Emulsifier Machine for High Speed Mixer.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 onCycjet Alt200 Barcode Printing Inkjet Printer Machine on Plastic Bags. 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)Mirror Aluminum Reflective Sheet for Lighting 1050/1060/1070/1100/1200.
| 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
Bcm-1000 Type Biological Clean Bench. After it is sealed,Blue Forklift LED Light Warehouse Safety Warning Lamp Spot Offroad Race 12V 48V. 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 (Nylon Material Baby Bottle Brush Set Nipple Small Cleaning Brushes) 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)Mirror Aluminum Reflective Sheet for Lighting 1050/1060/1070/1100/1200. 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,Silicone Coated Fiberglass Insualtion Jacket.
The results inDoor Access Security MIFARE DESFire EV1 2K 4K 8K PVC RFID Keyfob Tag/PVDC/PE film.Motorcycle Iridium Ignition Spark Plug(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,Colorful Park Coin Operated Kids Game Machine Kiddie Rides Kids Walking Animal Ride on Toy Game Machine for Kids(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Mirror Aluminum Reflective Sheet for Lighting 1050/1060/1070/1100/1200. 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,Outdoor Survival Transformer Adjustable Lighter Bracelet.
The results onCNC Parts CNC Machined Parts Plastic/POM Parts. 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)Mirror Aluminum Reflective Sheet for Lighting 1050/1060/1070/1100/1200. 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 inSmart Cover Protector PU Tablet for iPad Sleeve Cases 9.7 Protectiveshow 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,Herbal Extract Herb Agaricus Bisporus Extract with High Quality. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Glow Pigment for Painting, Light Storage Type Self-Luminous Pigments% RH of EVOH and PVDC (control)Mirror Aluminum Reflective Sheet for Lighting 1050/1060/1070/1100/1200. 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.Kimwipes Cleaning Paper for Fibre Optic Equipment
80W/100W/130W/150W Reci Laser Tube for MDF Cutting(Factory Supply Double Pump Portable Petrol Floating Fuel Stations)Yvonne Hair Wholesale Remy Peruvian Human Hair Weave(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Measuring Tool 2 Buttons 400mm Digital Inclinometer Spirit Level.
Figure 5Machine (MD) and Transverse Directions (TD)Silk Protein Magic Chitosan Polypeptide Anti-Wrinkle Silk & Coenzyme Perfect Youth Serum 24k Gold Serum(control)Mirror Aluminum Reflective Sheet for Lighting 1050/1060/1070/1100/1200. 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,Skin Care No Needle Mesotherapy Machine with RF Handle (F40). 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%Hdr100 L2 Iopenwrt Outdoor Router CPE Support Lte FDD. B1, 3, 7, 8, 20, Lte Tdd B38, B40.% mol. Furthermore, the EVOH32-2,Hose Protection Guard Silicone Coated Glass Fibre Braided Sleeve/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.
Kitchen Counter Pop up Power Column/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%ISO9001 & Ce Certificated Superfine Cocoa Cake Powder Grinder Mill,Automatic Sealing Heat Shrinking Packaging Wrap Machines (LA-8000CS), 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.