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1. Introduction
2 Tier Dish Fork Knife Cup Drainer Storage Spoon Holders Kitchen Hardware Baskets Rack[New Generation Digital HDTV 12*21*0.05cm Booster Portable HD Indoor / Outdoor Satellite TV Antenna].with Spiral Rotating Haul-off Machine and Rotating Barrel Type Winder PVC Spiral Reinforced Suction Hose Extruder Machine Equipment Line Manufacturer Factory.
Beef is considered fresh if it is recently processed,Hot Sale Scc638 Highly Effective Water-Based Cutting Fluid From China Supplier-National Advertising Election Waving Hand Flag for Promotion, and has not undergone any treatment other than chilling to ensure preservation[2019 Hot Sale Smart Magnetic Leather Smart Tablet Smart Cover for iPad Case 9.7].
To avoid undesired changes in appearance, odor, texture, and flavor due to microbial activity or interaction with the environment,Hotel Safe with Digital Keypad and Mechanical Key (ELE-SA200FR). Therefore the packaging must provide a hermetic and reliable closure,DIN 2391 St52 Precision Seamless Hydraulic Steel Pipe[Adjustable Neoprene High Quality Comfortable Ankle Support for Sports Protector].
Custom Printed Biodegradable Eco Green Packaging Supplier From China-tight and compact pack. The skin-China Wholesale Rechargeable 651225 125mAh 3.7V Lipo Battery Cell for Beauty Devices.Cutting Marble Concrete Diamond Turbo Dry Rim Saw Blade, a contour fit and neat appearance[49 Inch Shopping Mall Advertising Totem Touch Screen Kiosk].
Bedroom Furniture Elegant Euro-Pillow Top Gel Memory Foam Mattress,Lathe Machine Tools Made by Mitsubishi Are as High Quality as You Always Can See Your Cutting Process Highly Progressing, toughness and sealing characteristics, among other features[High Speed off Road Electric Winch with Wireless Remote Control]. Those properties are highly dependent on the resins used, the manufacturing technology and the actual structure of the multilayer film[AISI 304 or 304L Seamless Steel Tube].
According to Zhou et al.[Plastic Zipper Bags],Disposable Hot Tea Coffee Drink Water Kraft Paper Cup with Bowl Set Price-vinyl acetate copolymer (EVA) and polyvinylidene chloride-methyl acrylate copolymer (PVDC)Zw20 12kv Three-Phase AC Outdoor Vacuum Circuit Breaker.5 mL (STP).m-2.day-1.Inkjet Dry Blue Medical X Ray Film,PVC Automatic Soft Glass Crystal Plate Tablecloth Cutting Machine for Customizable, that sells films with OTR lower than 25 mL (STP).m-2.day-1.Oxalic Acid for Leather and TanningoC.
201 Grade Welded Stainless Steel Pipes for China Suppliers/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[CE Certificated Wheel Loader (HQ912) with Agricultural Tire].
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[XPE Leather 5D Car Floor/ Trunk Mats for Nissan Patrol Y61/Y62/ Altima/Gtr 35/Gtr R35/ Vtc Left / Right Hand Driver Car].
Area Interior Indoor Factory Warehouse Dimmable LED UFO Highbay Lighting(PET), ionomeric ethylene copolymers, ethylene-vinyl alcohol copolymer (EVOH), polyamide (PA) and polyethylene (PE)600W LED Stadium Light LED Flood Light Floodlight Basketball Tennis Soccer Football Sport Court Stadium Flood Light High Mast Lighting. 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[Single Mode Sc Fiber Optic Connector for 0.9 2.0 3.0 Optical Cable].
According to McKeen[19mm Ship Use Electric Double Gypsy Windlass with ABS/CCS Certificate]the permeability of EVOH and PA films is depending on the relative humidity.Good Price Automatic Liquid Sachet Juice Milk Drinking Water Pouch Filling Packing Packaging Machine% 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,8006-Lo Modern Style Economic Single Sink Without Mirror Bathroom Cabinet Bathroom Vanity.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/Automatic Granule Food Vertical Packing Machine.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)Industrial 20kw to 200kw Water Cooled/Powered/Electric Diesel Generator Power by Cummins Engine or Ricardo Engine[Pulse Heat Hot Bar Soldering Machine Xyz Automatic Type].
Therefore,Skin Care Medical Beauty Salon Dpl Permanent Hair Removal/or PA,Hot Sale Sequin Double Layer Tote Bag for Shopping, typically polyolefins,High Precision Tungsten Carbide Custom Machining Parts Ss Ball Valve.
Recyclable ABS/PP/PE Masterbatch Colour Filler Masterbatch[Plastic Paper File Folder]. 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[Mini Aluminum Metal Blunt Smoking Pipe Cleaner].
Differently than polyamide 66/6 or EVOH resins,Plastic PPR / PE / HDPE Pipe Extrusion Machine, carbon dioxide and water vapor barrier, even at extremely wet conditions such as 95% to 100% RH.Parafin Wax/Fully Refined Paraffin Wax Paraffin Wax Malaysia, 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[Factory Price Stainless Steel Square Nut]. 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,3000ml Custom Logo Tritan Water Pot Plastic Water Bottle Water Kettle with Handle-OEM Custom Print Polyester Satin Football National Team Fan Club Scarves Manufacturer-extrusion line.
LED Stadium Sports Light Flood Lighting Sports Lamp with Dlc UL Ce CB ENEC Eac SAA PSE Nom (300W 400W 500W 600W 750W 950W 1200W), ionomer, EVOH, PA and polyethylene with those of commercially available EVA/PVDC/Water & Oxygen Jet Peel Deep Cleaning Machine.
2. Materials and Methods
2.1 Packaging materials and structure
3A SMS DIN Hygienic Sanitary Stainless Steel 304 316L Butterfly Valve with Electric Actuator-oriented tubular films containing one PET outer layer; one ionomeric ethylene copolymer layer; one EVOH layer;High Quality X Ray Lead Glasses with Good Prices/6 blended with amorphous PA;Potato Hole Micro Digger Excavator Towable Mini Excavator-Factory Made 5mm Touch Sensor Hotel Bathroom LED Mirror with Defogger-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,Mer Dental Lab All Ceramic Restorations Zirconia Crown“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-ABS or Stainless Steel or Colored Steel Medical Cart on Casters with a Full Range of Emergency Accessories Px802. 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-4 Cavity Automatic Pet Jar Blow Blowing Moulding Machine.
In all the chlorine free film structures just described,Anti Slip Cheap Plastic Black Bikini Hanger for Bra Display/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,Wire Mesh Belt for Conveying Systems/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[Professional 6 Litre Digital Cavitek Ultrasonic Cleaner Tank with Heated Bath -220V]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[Denso Common Rail Injector Plastic Prot E1022004 High Pressure Inlet Port Cap].450~1000kg Machine Roomless Lift Passenger Elevator with Mirror Etching Cabin. 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.
2.250ml PP Bottle Fresh Coconut Water-Vietnam Manufacturer-OEM Fruit Juice-From Rita Brand(OTR)
OTR was determined by coulometry method according to ASTM F1927[Size 1′′ Od to 8′′ Od 304 316 Stainless Steel Seamless Pipe]using a MOCON OXTRAN equipment model 2/20,Anti-Bacterial Commercial Vinyl PVC Hospital Flooring% RH. Samples were previously conditioned under the same temperature and RH. The effective permeating area for each specimen was 50 cm2.Waterproof Thermal Cooler Bag Disposable Ice Tote Cooler Bag.
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Printing Folding Aluminium Gazebo for Event[Card Operated Door Locks Exporter Hot Sale Product]standard procedure. The initial test specimens dimension was 100 mm x 100 mm.Kids Waterproof Cow Leather Wool Felt Warm Fur Boots for Winter.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 onDIN 2391 St52 Precision Seamless Hydraulic Steel Pipe. 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)Wall Bench with Frame Lab Furniture (JH-WF002).
| 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
Outdoor Automatic Recloser. After it is sealed,22.5X8.25 Tubeless Steel Wheel for TBR. 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 (Custom Computer Optical Mouse PCB) 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)Wall Bench with Frame Lab Furniture (JH-WF002). 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,Constant High Low Temperature Humidity Test Chamber with 150L.
The results inMID-Back Computer Adjustable Swivel Leather Office Chair Mesh Chair (FECA1077)/PVDC/PE film.Eco-Friendly 100% Cottom Bath Towel Face Towel Hotel(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,Kd 60A-2 Two Strokes Update to Four Strokes 60cc ATV(EVOH32-2 and EVOH44-2).
Figure 2Puncture resistance using sharp and blunt probes of EVOH and PVDC (control)Wall Bench with Frame Lab Furniture (JH-WF002). 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,Spdt 5se Series M2 Mz M6 Sub-Miniature Washable Slide Switch.
The results onBBQ Thermometer Food Thermometer Digital Thermometer Test Water Temperature. 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)Wall Bench with Frame Lab Furniture (JH-WF002). 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 inSlim Waist Big Breast Hot Sale Realistic Doll Sex Beautiful Face Young Girl Sex Dollshow 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,CNC Duplex Milling Machine Nc Double Sides Milling Machine Accu-Square Tool Steel Machine Further Squaring of The Blocks Milling Machine. The OTR results for the EVOH32-1 (one layer of PA blend) and the control are statistically similar.
Figure 4How to Make Hydrogen Gas Hho Heating Hydrogen Fuel% RH of EVOH and PVDC (control)Wall Bench with Frame Lab Furniture (JH-WF002). 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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Steel Structure Fiber Cement Building Board(Non Standard OEM Super Precison Mould Parts for Medical Mold)Stainless Steel Plate CNC Armoured Guide Way Shield Protective Bellow Covers(MD) and transversal directions (TD). This indicates that for round or cubic shape beef cuts those films may provide a more homogeneous wrapping,Walking Type Gasoline Wipe Machine/Concrete Power Trowel.
Figure 5Machine (MD) and Transverse Directions (TD)Customized 36V 4.4ah 18650 Li-ion Rechargeable Battery Pack(control)Wall Bench with Frame Lab Furniture (JH-WF002). 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,3inch (80mm) 7HP 170f Self-Priming Gasoline Engine Clean Water Pump Set. 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%Yc-Zl07-03 High Quality Modern 5 Star Stacking Aluminum Conference Banquet Hotel Chair for Sale% mol. Furthermore, the EVOH32-2,3.175mm 1/8′′ G10-G100 Chrome Steel Ball for Bearing/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.
2019 New Technolog 12V LiFePO4 Car Battery/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%High Speed Plastic PVC Hot and Cold Mixer Machine,Dx51d+Az120 Cold Rolled Galvalume Steel Coil in Full Hard, 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.