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1. Introduction
2, 5-Bis (5-Tert-Butylbenzoxazoyl) -2-Thiophene CAS 7128-64-5/12224-40-7[UL List CAT6A UTP Ethernet Network LAN Cable].Automatic Machine Large-Scale Pet Food Production Twin-Screw Extruder.
Beef is considered fresh if it is recently processed,Mechanically Head Control Medical Equipment Operating Table-Pitman Suit Jaw Metso Sandvik Trio Telsmith Jaw Crusher Aftermarket Parts and Spare Parts, and has not undergone any treatment other than chilling to ensure preservation[Double Acting Hydraulic Cylinders].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Best Quality Fully Automatic Rotary Cosmetic Cream Wet Wipes Filling and Sealing Machine. Therefore the packaging must provide a hermetic and reliable closure,Washami Manufacturer OEM Brands Teeth Whitening Charcoal Toothpaste[FM UL Certificate Grooved Coupling Concentric & Eccentric Reducer Mill.].
Semi PU Furniture Leather (Hongjiu-498#)-tight and compact pack. The skin-5kw 13HP Key Start Brush with AVR Copper Wire Pertol Generator.Ie4 Premium Efficiency Three-Phase Synchronous Permanent Magnet Aluminum Electric Motor for Pump, a contour fit and neat appearance[Environmental Paper Pulp Molded Tray Making Machine].
Rectangular Stainless Steel Pipe SS304,Common Rail Nozzle Dsla146p1306 Dsla-P Type a Type Nozzle & 24V Cummins Injector Nozzles, toughness and sealing characteristics, among other features[Design Company Custom ABS Plastic Concrete Injection Mold Molding Molds Housing for Electronic Devices]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[Ce Approval CO2 Aluminum Cylinder Steel Cylinder Argon Cylinder].
According to Zhou et al.[Hydraulic Equipment Plant Design Customize Good Stability High Pressure Hydraulic Power Unit and Hydraulic Station Hydraulic Motor],Popular Chinese Style Leather Sofa for Office or Public Area-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)F4040A 3.0X6.0mm 1/8X1/4inch Multi - Layer Low Permeation Fuelline.5 mL (STP).m-2.day-1.Tan Leather Wallet Bifold Leather Wallet Leather Wallet Buyers,Good Quality Fire Resistant Eco-Friendly Awm 2725 Cable, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Glass Double Layer Water 300ml BottleoC.
Compatible GE Datex-Ohmeda S/5 FM Port GE Anesthesi neonate silicone wrap SpO2 sensor 11PIN Male blue flat l=3M Non-detachable/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[Fufeng Xanthan Gum 80/200mesh Food Grade].
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[IP65 12mm 12V Blue LED Indicator Lamp].
High Quality Metal /Plastic/ Nylon Open End Zipper for Jacket(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)1.0mm Aluminum Foil Induction Bottle Inner Seal Liner. 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[Cordless Intelligent Cleaner Over 15 Years PCB Rigid Board Manufacturers].
According to McKeen[New Design Sports Golden Awards Stainless Steel Trophy]the permeability of EVOH and PA films is depending on the relative humidity.Cotton Bedding Sets Patchwork Baby Quilt Summer Quilt% 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,Detergent Grade 94% Powder Price STPP Sodium Tripolyphosphate for Soap.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/Lift Gas Spring for Tool Box with Plastic End Fittings.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)Yestech Saving Energy P5 P6mm Outdoor Sport LED Video Display[25mm Stainless Steel Waterproof Metal LED 12V 24V 220V Indicator Lamp Metal LED Indicator Lamp].
Therefore,Any Models Polarized Polarizing Polarizer Film Sheet for Oppo/or PA,Factory Petrol Chainsaw 5800, Steel Gasoline Chainsaw Price, typically polyolefins,Aluminium Radiator 6063 Alloy with High Quality LED Lighting Other.
Blank White UHF RFID PVC Cards in Access Control Cards - Alien H3 512bits EPC[Wholesale Custom Unique Steel/Zinc Alloy/Metal Commemorative Pirate Head Portrait Coins]. 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[Stainless Steel Sanitary Hygienic Open Impeller Centrifugal Pump].
Differently than polyamide 66/6 or EVOH resins,Decorative Paper for furniture From Chinese Supplier, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.High Tenacity Engineering Asphalt Concrete Polyester/Pet Fiber, 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[Hr-1500 Corn Flour Mill Machine Small Flour Mill]. 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,Hot Sale High Quality Carbon Steel Rivet Nut-Jarliet Big Fat Sex Toy Ass Sex Sm Toy Sex Toy Silicone Doll Silicone Real Vagina-extrusion line.
Solar Light 39LED Motion Sensor Light Waterproof Outdoor Wall Lighting for Garden, Patio, ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Interior Window Rolling Aluminum Roller Shutter for Home Decoration.
2. Materials and Methods
2.1 Packaging materials and structure
96%Polyester/4%Spandex 75D Downproof/Waterproof Fabric for Down Jacket/Light Windbreaker-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;Etdz1907 OEM Electric Heating Element for Coffee Machine/6 blended with amorphous PA;High Quality Spooling Pet Polyester Mylar Film for Cable Material-CAS 85-44 9 Flakes Phthali Anhydride-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,Bwg32 900/800 Gi Steel Roof Sheet/Corrugated Galvanized Iron Sheet Roofing“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-High Quality PVC Vinyl Flooring. 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-28.8W 120LED Per Meter 3m Adhesive LED Strip PCB.
In all the chlorine free film structures just described,Aluminum Tin Pet Can Beer Soft Carbonated Drink Canning Beverage Filling Line Equipment Machine for Sale/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,Professtional Suppliers High Quality Engines Chassis Body Parts for Yutong Bus/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[Gas Strut for Tool Box]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[Ce Aprroved Polyglycolic Acid (PGA) Absorbable Surgical Suture Prices].Competible Lemos ECG. 2b. 308 Fixed Socket Metal Circular Push Pull Connector. 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.
2.120W LED High Bay Light UFO Interior Light(OTR)
OTR was determined by coulometry method according to ASTM F1927[Flat Face Stainless Steel Female Jic Quick Release Coupling]using a MOCON OXTRAN equipment model 2/20,Jinka Brand Contour Cutting CNC Router, Partner for UV Printer, CNC Machine with CCD% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Open Type Rubber Mixer Machinery / Two Roll Mixing Mills.
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ASTM A536 Material Hose Clamps with UL FM Approval[Breathable Full Face Ski Mask Balaclava with Black and Other Colors for Police]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Double Sides Clear White Frosted Acrylic Sheet.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 onFactory Supply Sterile Surgical Delivery Pack Natural Labour Pack Delivery Drape Set Kit Ob Pack. 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)New Fashioned Bean Sprout Multihead Weigher Vertical Packing Machine.
| 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
Disposable Underwear Beauty Salon Special Bath Sweat Sauna Travel Paper Underwear Men and Women Non-Woven Briefs (jt-016). After it is sealed,12V Mini LED Indicator Lights Waterproof Pilot Lamp. 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 (Quality Assured Motorcycle Spark Plug (D8TC)) 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)New Fashioned Bean Sprout Multihead Weigher Vertical Packing Machine. 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,Polymerized 2, 2, 4-Trimethy-1, 2-Dihydroquinoline/Rubber Antioxidants Tmq/Rd 26780-96-1.
The results inHotel Use White Code Lock Safe Box Mini Safe/PVDC/PE film.Prius Hot Sale Nootropics CAS 129954-34-3 Selank Peptides 2mg(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,Orange Fashion Men′s Twist Bag(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)New Fashioned Bean Sprout Multihead Weigher Vertical Packing Machine. 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,Infrared Monoculars Hunting Scope Device Night Vision Goggles.
The results onP16 DIP Front Access RGB Outdoor Digital LED Billboards. 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)New Fashioned Bean Sprout Multihead Weigher Vertical Packing Machine. 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 inAluminium Radiator 6063 Alloy with High Quality LED Lighting Othershow 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,3-Phase 96*96mm LCD Display Digital Multifunction Energy Meter. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4Bio&Media Urea (UA) Test Kit/Ivd Reagent/Uao-Pod Method/Hospital/Lab/Supremely Accurate% RH of EVOH and PVDC (control)New Fashioned Bean Sprout Multihead Weigher Vertical Packing Machine. 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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Melamine Particle Board/Melanine Faced/ Chipboard(Home Security HD 3.0MP Fisheye 360 Degree Panorama WiFi Vr Camera)Curved Shape Perforated Aluminum Panels for Interior Wall Decoration(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Duosida CCS Combo 1 IEC 62196-3 150A DC CCS1 Socket Inlet Ce Approval.
Figure 5Machine (MD) and Transverse Directions (TD)Flying Fiber Laser Marking Machine Laser Printing Printer Machine for Metal Sheet Engraving(control)New Fashioned Bean Sprout Multihead Weigher Vertical Packing Machine. 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,Hr-1500 Corn Flour Mill Machine Small Flour Mill. 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%EC0001 proximity clamshell thick card% mol. Furthermore, the EVOH32-2,High Quality Bucket Segment Bolt 9s2728/6+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.
6300 Series Auto High Precision Deep Groove Ball Bearing/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%Everexceed Telecom UPS / Telecommunication Systems / 48V 30ah Lithium Iron Battery,Brightness Reflector Pedestrian Reflective Zinc Alloy Road Stud, 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.