







*BacShield® has not been reviewed or accepted by the EPA for pathogenic efficacy claims.
*BacShield® has not been reviewed or accepted by the EPA for pathogenic efficacy claims.
One hundred microliter of feline coronavirus (1×105 pfu/ml) suspension was inoculated onto the sterile 6 well tissue culture plates. 0.3% chitosan solution or vehicle control (1% acetic acid) was sprayed using an electrospray gun. After incubating for 15 and 30 min, the wells were rinsed with EMEM media which were transferred to monolayer of CRFK cells grown in the 6 well tissue culture plate. After viral absorption for 1 hour, EMEM was removed and then 0.5% soft agar in EMEM was overlaid. After incubating for 72 hours, viral plaque indicated by a clear circle was determined by 0.3% crystal violet staining. A treatment with 0.3% chitosan for 15 min decreased feline coronavirus from 1×104 pfu to 1×101 pfu and treatment for 30 min completely killed feline corona virus, while a treatment with vehicle control (1% acetic acid) did not affect the viability of feline coronavirus.
The report indicates that 0.3% chitosan solution applied via electrostatic sprayer was effective at initially reducing the number of “pfu’s” (plaque forming units, which is similar to “cfu’s colony forming units” when working with bacteria) and furthermore at 30 minutes left no viable virus. The pfu or cfu does not exactly correspond to the actual number of virus particles or bacteria cells, but it is close. The difference is that more than one virus particle or bacteria cell could be the cause of one of the colonies which shows up on the petri dish. However, the absence of a plaque or colony is almost certainly evidence that there is not any virus or bacteria present. So, in a nutshell, trying two different methods to treat a 1X10^4 (10,000 units per ml) virus load, one with 1% acetic acid and one with 0.3% chitosan, showed that the acetic acid did not reduce the count while the chitosan reduced counts by 99.9% in 15 minutes and the chitosan treatment completely eliminated (within limits of experiment) the virus in the 30 minute contact.
*BacShield® has not been reviewed or accepted by the EPA for pathogenic efficacy claims.
BacShield RTU is a revolutionary solution that will be used to restore the public’s confidence in returning to commercial spaces. Confidence is the key. The public is seeking solutions to safe environments. Prevention measures must include surface protection. This means surfaces must be cleaned and free of pathogenic organisms. The question is how do we insure they remain microbial free after cleaning and resumed occupancy.
In a disposable society, the options for a sustainable, on-going protection system of defense against microbes has not been considered. Today, that system of defense is available. It is BacShield RTU.
BacShield RTU is an EPA registered (#81446-2) Bacteria growth inhibitor and odor causing bacteria anti-microbial. BacShield RTU dries on the surface to create an invisible anti-microbial shield. BacShield RTU provides long lasting protection. BacShield RTU contains no phosphates, is ammonia free and bleach free making it low VOC and has extremely high PEL or Personal Exposure Limits which means the applicator does not need PPE or Personal Protective Equipment (Respirators) to install. (EPA-HQ-OPP-2007-0566-0019, Chitin Case 6063).
BacShield RTU is for indoor and outdoor use! BacShield RTU cleans and protects which makes your cleaning program more effective. The persistence of the film means that the material’s properties allow it to continue working for long periods after application. This reduces the cost of cleaning and reduces the environmental impact of repeated application of cleaning chemistry.
Additional EPA Registrations are being sought based on extensive testing from Microchem Laboratories and at major universities including Mississippi State University. Until these claims are registered with the EPA, no claim or representation can be made or implied as to the suitability of BacShield RTU on these organisms.
The primary benefits are:
A. Persistent or ON-GOING antimicrobial activity. BacShield RTU has been tested on a large list of other microbes for 21-days, 35-days, 130-days and for 12-months on mold and mildew.
B. Non-Toxic & All-Natural- It can be sprayed in a mist without Lung Damage (low PPE, very high PEL). The national supply is also running low on PPE organic respirators. This is a Very big point. Respirators can be used where there is a greater need than chemical application. Post application, waste water supplies are not contaminated.
C. Available – Raw material to manufacture millions of gallons is immediately available and BacShield RTU can cover 6,000- 9,000 ft2 per gallon.
D. Sustainable – BacShield RTU is derived from the Polysaccharide from Crustacean Shells. It is the second most prevalent polymer on earth.
E. Inexpensive – Material cost is less than $ 0.015 ft2. (Companies are charging $ 0.14 to over $ 3.00 a ft2 to spray EPA List-N disinfectants during the pandemic)
F. Ease & Efficacy of Application – BacShield RTU can be applied by steamer, electrostatic sprayer or foggers. Steam is the recommended method under the Steam & Shield patented process as the dry steam destroys bacteria and virus and applies the BacShield RTU in a method that dries fast with a hard coating shell for increased durability and longevity.
*BacShield® has not been reviewed or accepted by the EPA for pathogenic efficacy claims.
The tests herein were conducted at Mississippi State University by Cooper Brookshire1, Michael Flose1, Issac Jumper1, Joo Youn Park1, Stanley Weller2, Lloyd Starks2, Keun Seok Seo1
1College of Veterinary Medicine, Mississippi State University, Mississippi state, MS 39762
2NOVTECH, LLC, Chattanooga, TN 37421
Presented at the US Army Medical Research and Development Conference on (DATE).
Antimicrobial and antibiofilm effect of chitosan solutions against methicillin resistant Staphylococcus aureus
Tested to 35 Days Persistent Kill
*BacShield® has not been reviewed or accepted by the EPA for pathogenic efficacy claims.
It is impossible to maintain a facility and expect a healthy environment if the surfaces are not tested, the data collected and evaluated, the success or failure is scored and the results are reported and acted upon to make changes if necessary.
This process may be easier than one may think. SilTanium does not sell or represent any of the equipment that is widely available on the market. However, the short guideline below may aid a service provider or facility decision maker in choosing a system that meets their needs.
The advantages of testing are clear. What may not be clear is that testing opens the possibility to save money too. Changes to chemicals used may reduce cost or increase effectiveness. Clear process direction to contractors and service providers may improve contract value.
Measuring results can be a facility internal operation or part of a service providers system. SilTanium lists service providers that may be able to help in this area in the Service / Installation Partners in our main menu.
Measure:
1. Test surfaces
2. Data information collection
3. Data evaluation
4. Score results
5. Report results so additional training or systems will be added as required
Directions for Use
1. Using an Ultrasnap testing device, take a swab sample of an area about 4 inches squared or 10 centimeters squared. (Or the equivalent on an uneven surface.) The Ultrasnap swabs come pre-moistened with special liquid that breaks down biofilm and exposes ATP. Or collect a water sample with an Aquasnap testing device. (Aquasnap devices will have slightly different directions.)
2. Place Ultrasnap swab back into swab tube.
3. Holding the swab tube firmly, use your thumb and forefinger to break the snap valve on the tube by bending it back and forth.
4. Squeeze the end bulb twice, expelling all of the liquid down the swab shaft.
5. Bathe swab bud in the liquid (this is a testing reagent) by shaking the tube for 5 seconds.
6. Open lid on SystemSURE and place Ultrasnap tube into testing chamber and close lid.
7. Press OK button to initiate reading. Results will be displayed in 15 seconds.
8. Read results.
a. Easy to understand PASS (check mark) CAUTION (!) or FAIL (X) symbols make results easy to understand immediately.
b. Results are displayed in Relative Light Units (RLU). More contamination = higher RLU results.
c. Programmed location names for each sample are displayed on the screen, along with a location number, making it easy to tell where each testing sample came from. Up to 251 location names can be programmed.
d. Upper and lower pass/fail limits are set for each location and are displayed on screen.
e. 20 sample plans can be created. Each sample plan has specific programmed locations that should be tested when running a particular plan.
f. User identification can be assigned to track performance and traceability.
9. SystemSURE Plus comes with SURE-Trend data analysis and charting software so you can connect it with your computer and make a database of what you have tested.
Example test performed by DPM, certified BacShield Service Provider
Test performed at a local, well-run restaurant. The hostess walked us in, sprayed disinfectant on the table, and wiped the surface off. We were happy to see that the table was disinfected. Just to be sure it was truly disinfected; the following test was administered:
Test 1 – Table Disinfected Before Seating Us
Note: 50 or below is hospital-grade disinfection.
We discussed leaving the restaurant after seeing this result.
Test 2 (Retest):
1. Cleaned Surface with Prep Chemical
2. Applied BacShield® and Allowed Dry Time
3.. Retested
A major change to the surface environment. Now 20 points lower than max hospital grade disinfecting.
Test 3:
This is the table one over that was not in use for social distancing. Another failure!
*BacShield® has not been reviewed or accepted by the EPA for pathogenic efficacy claims.
The greatest crisis facing the USA today is the loss of a dynamic and robust economy. The only way to get the population back to work is for employees and customers to be confident in their safety. The environment must be safe. Safe from disease and safe from future environmental pollution. This requires a new science and an acceptance of those realities. The science must be sure to protect health, save time and money and be safe and non-toxic.
There is one system designed to answer the challenge. Steam and Shield, the patented process using dry steam vapor to disinfect and sanitize surfaces with an aqueous solution of Chitosan all in one-step. The steam sterilizes and disinfects the surface while Chitosan inhibits growth of wide variety bacteria and other microbes. Chitosan possesses a higher antibacterial activity, a broader spectra of activity, a killing rate for a sustained period of time (months).
Chitosan interferes with the negatively charged residues of macromolecules at the cell surface. Chitosan interacts with the membrane of the cell to alter cell permeability. In another mechanism the binding of chitosan with DNA inhibits RNA synthesis.
Staphylococcus aureus laboratory test results indicate that the dry vapor steam containing chitosan sterilize and disinfect the surface of the of the chitosan treated glass for 2, 6 and 24-hours after re-inoculation with S. aureus AATCC 6538. Tests on glass and cotton continued to deliver s. aureus AATCC 6538 reduction up to 3 weeks by 99.9997% on glass and 99.998% on cotton.*
A similar test on AATCC 33592 MRSA was tested for 4 months with a reduction of 99.996% on glass and 99.992% on cotton.*
Steam and Shield, US patent # US 9,149,036 B1 (Oct 6, 2015) was designed to use the chitosan solution applied as a dry vapor steam of at least 275° F which will kill bacteria or virus on contact. The chitosan dries quickly into a hard shield which provides a clear thin film with persistent kill. In the patent, both S. aureus (AATCC 6538) and MRSA (AATCC 33592) are destroyed for weeks and months.
This means that the cleaning, removal, & disinfecting of pathogenic contaminated surfaces is cleaned and then treated for future antimicrobial protection in one simple step. The effectiveness and simplicity of the Steam and Shield system.
A. Persistent or ON-GOING antimicrobial activity. Tested to 3-weeks on S. aureus AATCC 6538 (Staph) and to 4-months & 8-days on S. aureus AATCC 33592 (MRSA).
B. Non-Toxic & All-Natural- It can be sprayed in a mist without Lung Damage (HIGH PEL). No other current item on the EPA N List (registered disinfectants) can claim this. The nation is also running on on PPE organic respirators. This is a Very big point. Respirators can be used where there is a greater need than chemical application. Post application, waste water supplies are not contaminated.
C. Available– Raw material to manufacture millions of gallons with coverage rates of 6,000- 9,000 ft2 per gallon.
D. Sustainable– Chitosan comes from the Polysaccharide from Crustacean Shells. It is the second most prevalent polymer on earth.
E. Inexpensive– Application of this material is less than $ 0.025 ft2 for material and labor. (Companies are charging $ 0.14 to over $ 3.00 a ft2 to spray EPA N List disinfectants during the pandemic)
F. Ease & Efficacy of Application- Chitosan can be applied by steamer, electrostatic sprayer or foggers. Steam is the recommended method under the Steam & Shield patented process as the dry steam destroys bacteria and virus and applies the Chitosan film in a method that dries fast with a hard coating shell for increased durability and longevity.
* Reported on Patent US 9,149,036 B1
*BacShield® has not been reviewed or accepted by the EPA for pathogenic efficacy claims.
*BacShield® has not been reviewed or accepted by the EPA for pathogenic efficacy claims.
*BacShield® has not been reviewed or accepted by the EPA for pathogenic efficacy claims.
Effect of increasing Chitosan Solution concentrations on growth of E. Coli 015H7 in broth medium
Mississippi State University
Shecoya B. White, Ph.D.
Assistant Professor
Food Science, Nutrition and Health Promotion
Figure 1. Results from imaging of bioluminescent E. Coli strains cultured in the presence of chitosan dilutions. The stock Chitosan solution was diluted in either LB broth or BHI broth to yield the following final concentrations: 25.00%, 12.50%, 6.25%, 3.13%, 1.06%, or 0% (control). Bioluminescent images were then taken every three hours for twenty-four hours using IVIS Lumina XRMS machine. To confirm IVIS microtiter data E. coli (9 log CFU/ml) was inoculated into BHI broth containing either 6.25% or 12.50% Chitosan solution and incubated for twenty-four hours. Samples were plated and incubated for an additional twenty-four hours at 37◦C to determine microbial growth. Colonies were then counted, and CFU/mL was calculated.
Table 1. Actual plate counts from microtiter plates treated with increasing concentrations of Chitosan solution.
*BacShield® has not been reviewed or accepted by the EPA for pathogenic efficacy claims.
This information contained on this website is confidential, privileged and only for the information of the intended recipient and may not be used, published or redistributed without the prior written consent of Siltanium Corporation.
Surface, Air, Measure
All surfaces in an environment require cleaning and disinfection. This includes floors, walls, ceilings and all furniture and fixtures.
Some areas require daily care, some more periodic care scheduled weekly, monthly, quarterly or annually. Some processes vary in intensity and timing. Restroom sinks and toilets are cleaned daily, while floors are mopped once or twice a week and deep scrubbed and extracted annually or bi-annually. Carpet may be lightly vacuumed daily or weekly but monthly or quarterly are cleaned with a deeper method like low-moisture extraction or steam cleaning. Walls and ceilings are generally only wiped when visually dirty and thoroughly cleaned once a year.
Personal effects in a work space are generally only cleaned and disinfected by the employee. Common work space is dusted but rarely sanitized or disinfected. Racks and shelves that contain merchandise for sale in retail stores may only be cleaned once or twice a year.
These cleaning systems, intensity levels and time frequencies are not enough since the tragic COVID-19 outbreak. To insure all employees and customers entering any facility that there is a true Shield of protection, the following items must be in place.
The chemicals and equipment may vary based on the specific environmental needs and facility managers purchasing preferences, but training, frequency, and measuring the antibacterial results must become a serious and enforced protocol.
In addition, the application BacShield, will act as an added insurance policy to eliminate the growth of microbes while no one is watching or working.
Quality Facility Care Protocols Include:
Surface:
Proper frequency schedules must be implemented, managed and enforced.
1. Sweep, Vacuum, Dust and mop
2. Disinfect and Sanitize
a. Protective gear
i. Gloves
ii. Masks
b. Disinfect with steam OR
c. Disinfect with chemicals
i. Use only chemicals proven to achieve pathogen destruction
d. Maintain quality standards
i. Test surfaces for microbial activity
ii. Adjust processes to meet standards
3. Protect
a. Sustained Systems with Bacteria growth inhibitor and odor causing bacteria anti-microbial. BacShield RTU dries on the surface to create an invisible anti-microbial shield.
Air:
1. HVAC Filters
a. Change as recommended by equipment manufacturer
i. Evaluate enhanced particulate filters
ii. Evaluate other microbe destruction systems such as UV Light and Hepa.
b. Install enhanced systems or service items to location such as UV light sterilization and air purifiers
Measure:
1. Test- Facility
2. Data information collection
3. Data evaluation
4. Score results
5. Report results so additional training or systems will be added as required
Ron Gilmer
Ron plays a multifunctional roll at SilTanium coordinating operations and distribution and overseeing sales information and communication relationships.
Ron comes to SilTanium with sales and marketing experience and executive level management in plant operations. Distinguished skills in business development, continuous process improvement, and new process integration. Other core competency in lean manufacturing technologies, production processes, cost containment, facility and equipment control, project management, quality and performance improvement, and human resources.
Professional Background:
Operations manager with top gun powder and architectural coating.
Operations manager with Jinsung T.E.C.
Application engineer with The Valspar Corporation
Production manager with Suzuki Manufacturing of America
Senior shift supervisor with Kobelco of America, Inc.
Production supervisor with utility trailer manufacturing corporation.
A Native of Daleville, Alabama Ron now resides in Calhoun Georgia with his wife Stacy. Ron has two Daughters Cassie and Ashley. Ron received an Industrial Engineering Degree from Auburn University. Military Service with the Army National Guard.
John A Duffy Jr
In 2018 John, along with Pro Football Hall of Famer Ray Lewis and three other partners, came together to form LEGENDS Access (legendsaccess.com). LEGENDS Access is a world class sports marketing organization specializing in Sports and Entertainment LEGENDS. As the Executive Vice President and Chief Commercial Officer, John works closely with the LEGEND community and corporate clients including Sports Illustrated, MillerCoors. UPS, Capital One, DrinkTru Inc., HealthRight Products and BodyChek Wellness.
John also created Celly U.S.A. a consulting firm optimizing Corporate Partnerships for Sports and Entertainment Venues as well as consulting for major brands focused on foodservice channel development. One of John’s major clients included L.A. Libations, a next-generation beverage incubator/accelerator and innovation partner of The Coca-Cola Company.
For the prior 22 years John was employed by the Coca-Cola System in leadership roles of increasing responsibility. Most recently (Vice President of National Sales) leading the organization responsible for Coca-Cola’s Sysco Foodservice business across North America and accounting for over $1 billion in revenue. Prior to this role John built and led the organization responsible for all sports, entertainment, and marketing asset agreements across the Eastern United States as Vice President of Marketing Assets. John and his team were accountable for more than 100 of the most iconic sports & entertainment partnerships including Madison Square Garden, Boston Red Sox, Universal Studios, Tampa Bay Lightning, Atlanta Braves, University of Alabama, University of GA, Boston College, Atlanta Hawks, Boston Bruins and Walt Disney World.
A native of Bourne, Massachusetts John resides in Kennesaw, Georgia with his wife Wendy, son John and daughters Catherine and Julia. John holds a BA in Economics from the University of Massachusetts, Dartmouth and an MBA from Suffolk University in Boston. John is a member of the Kennesaw State University Athletics Association and is a USA Hockey Certified Level 4 Youth Hockey Coach. John is also active in the fight to eradicate Human Trafficking working with the SAWT League (Sports World Against Trafficking).
Tom McNiff
In 2001, McNiff started the SilTanium Corporation. SilTanium is a technology innovator and specialty clear coatings manufacturer with an internal service division operating in the southeast United States. In 2011, SilTanium started the Alliance Partner program of training and supporting select companies in the United States to deliver the SilTanium developed and branded coating systems nationwide.
Prior to 2001, McNiff owned and operated a nylon recycling company using carpet fiber waste steams as a feedstock for compounded resins primarily sold in the automotive parts sector. His career started in the carpet business as a salesman and transitioned to the management of a recycling initiative to divert carpet waste from the landfill through converting it to a plastic / wood sheet as a replacement for rain forest plywood in flooring underlayment.
Born in upstate New York, McNiff lived in Lancaster, Pennsylvania and Southern Pines, North Carolina. A graduate of East Carolina University, McNiff now resides in Cartersville Georgia with his wife Linda and three children.
Process Installation Instructions for Steam and Shield and BacShield
BacShield can be applied in may ways from wiping and common garden sprayer to Dry Steam applicators (The preferred one-step process called Steam & Shield) to electrostatic sprayers and foggers.
When using the Steam and Shield patented method, it is critical to apply steam according to the patent and manufacturers instructions. The chitosan treatment solution (BacShield RTU) is used in the form of a vapor to sterilize a surface and simultaneously coat the surface with a dry film of chitosan. If the chitosan treatment solution is an aqueous solution then the vapor will be steam. Any kind of steam generating system can be used to convert the chitosan aqueous treatment solution to steam. However, dry vapor steam is preferred wherein the steam is at a temperature of at least 275° F., preferably 275° F. to 310° F. Dry vapor steam is steam having a temperature ranging from 240° F. to 310° F., a water moisture content of 4% to 6%, and pressure up to 140 PSI.
In order to sanitize and disinfect a surface and apply a film of chitosan to the surface using the chitosan treatment solution, the chitosan treatment solution is placed in the dry vapor steam generating system. The chitosan treatment solution is heated in the dry vapor steam generating system to produce vapor steam at a temperature of at least 275° F. The steam is 60 applied to the surface for 1 to 20 seconds, preferably 5 to 10 seconds, at an angle of preferably approximately 90°, and at a distance of 1 to 20 inches, preferably 6-10 inches. After application of the steam the surface has a thin film of chitosan deposited thereon. A composition of steam and chitosan is 65 formed in the generation of dry vapor steam from the chitosan treatment solution. No chitosan treatment solution in its liquid form is applied to the surface in this process. The steam sterilizes/disinfects the surface. The chitosan in the steam vapor deposits on the surface forming a water resistant anti- microbial durable film of chitosan. The chitosan film inhibits growth of microbes on the surface for a sustained period of time. The method is referred to as the chitosan vapor steam treatment or the chitosan dry vapor steam treatment.
Before starting the process, drain the chitosan from previous use from the steam tank. Clean the reservoir with water and white vinegar. Re-fill reservoir with chitosan to the manufacturers recommended fill quantity for optimum performance.
The Chitosan solution may amber in color in the steam heating chamber. Chitosan is made from polysaccharide which is similar to sugar. Check the chitosan color as it leaves the spray end of the applicator by spraying into a clear plastic cup. The material should be clear or slightly yellow tinged. If material color should be too dark to apply on a white surface, cease operations, allow unit to completely cool and then discard the chitosan and re-fill the tank with fresh material.
Slight coloring will not affect the efficacy of the chitosan. Chitosan is carried by the water steam. The carnalized sugar type material generally stays in the steamer unit.
Steamers and foggers are also useful tools for chitosan application. However, neither unit will disinfect on contact as will dry steam. Properly prepare the surface with the proper cleaners and disinfectants.
Then use the electrostatic sprayer or fogger according to manufacturer’s directions.
Primary Benefits
Secondary Benefits
Patented Process- Steam and Shield
A method for sanitizing and disinfecting a surface using an aqueous solution of chitosan. The aqueous solution is heated to convert the aqueous solution to a steam vapor containing chitosan. The surface is treated with the steam, thereby disinfecting the surface and simultaneously depositing the chitosan from the steam onto the surface. The steam will also penetrate porous surfaces. An antimicrobial film of chitosan is thereby formed on the surface. The steam vapor sterilizes the surface and the chitosan film inhibits growth of bacteria and other microbes on the surface for several months. The steam containing the chitosan can be generated from an aqueous solution of chitosan heated in standard commercial and home-use steam generators. This chitosan vapor steam treatment of surfaces can be used on any hard surface or soft surface.
Martin, T.P., et al., “Initiated chemical vapor deposition of antimicrobial polymer coatings.” Biomaterials 28 (2007) 909-915. cited by examiner.
Torres-Giner, S., et al., “Development of Active Antimicrobial Fiber Based Chitosan Polysaccharide Nanostructures using Electrospinning”. Eng. Life. Sci. 2008, 8, No. 3, 303-314. cited by examiner .
Goy, Rejane C, et al., “A Review of the Antimicrobial Activity of Chitosan”. Polimeros: Ciencia e Tecnologia, vol. 19, No. 3, pp. 241-247, 2009. cited by examiner .
Zhao, Li-Ming, et al., “Preparation and Application of Chitosan Nanoparticles and Nanofibers”. Brazilian Journal of Chemical Engineering. vol. 28, No. 03, pp. 353-362, Jul.-Sep. 2011. cited by examiner .
Kubacka, Anna, et al., “Understanding the antimicrobial mechanism of TiO2-based nanocomposite films in a pathogenic bacterium”. Scientific Reports 4:4134, Feb. 19, 2014, pp. 1-9. cited by examiner .
Duan, J., et al., “Storability of Antimicrobial Chitosan-Lysozyme Composite Coating and Film-Forming Solutions.” Journal of Food Science, vol. 73, Nr.6, 2008, M321-M329. cited by examiner .
Tripathi, Shipra, et al., “Chitosan based antimicrobial films for food packaging applications”. e-Polymers 2008, No. 093, pp. 1-7. cited by examiner .
Coma, Veronique, “Polysaccharide-based Biomaterials with Antimicrobial and Antioxidant Properties”. Polimeros, vol. 23, N. 3, pp. 287-297, 2013. cited by examiner .
Sanchez-Gonzalez, Laura, et al., “Antimicrobial activity of polysaccharide films containing essential oils”. Food Control 22 (2011) 1302-1310. cited by examiner .
Coma, V, et al., “Edible Antimicrobial Films Based on Chitosan Matrix”. Food Microbiology and Safety, pp. 1-8. No other reference information available. cited by examiner.