What You Should Know About Concussions https://www.rallypoint.com/command-post/what-you-should-know-about-concussions <div class="images-v2-count-1"><div class="content-picture image-v2-number-1" id="image-724952"> <div class="social_icons social-buttons-on-image"> <a href='https://www.facebook.com/sharer/sharer.php?u=https%3A%2F%2Fwww.rallypoint.com%2Fanswers%2Fwhat-you-should-know-about-concussions%3Futm_source%3DFacebook%26utm_medium%3Dorganic%26utm_campaign%3DShare%20to%20facebook' target="_blank" class='social-share-button facebook-share-button'><i class="fa fa-facebook-f"></i></a> <a href="https://twitter.com/intent/tweet?text=What+You+Should+Know+About+Concussions&amp;url=https%3A%2F%2Fwww.rallypoint.com%2Fanswers%2Fwhat-you-should-know-about-concussions&amp;via=RallyPoint" target="_blank" class="social-share-button twitter-custom-share-button"><i class="fa fa-twitter"></i></a> <a href="mailto:?subject=Check this out on RallyPoint!&body=Hi, I thought you would find this interesting:%0D%0AWhat You Should Know About Concussions%0D%0A %0D%0AHere is the link: https://www.rallypoint.com/answers/what-you-should-know-about-concussions" target="_blank" class="social-share-button email-share-button"><i class="fa fa-envelope"></i></a> </div> <a class="fancybox" rel="0953af4f47a7d0974c66d1c7eaae5420" href="https://d1ndsj6b8hkqu9.cloudfront.net/pictures/images/000/724/952/for_gallery_v2/2daf7d12.jpg"><img src="https://d1ndsj6b8hkqu9.cloudfront.net/pictures/images/000/724/952/large_v3/2daf7d12.jpg" alt="2daf7d12" /></a></div></div>By USPHS CAPT Tricia Booker <br />Traumatic Brain Injury Center of Excellence <br /><br />Having your bell rung. Getting knocked out. Seeing stars. <br /><br />You might use one of those terms to describe a hard hit to your head. But your doctor might call it something else: a possible traumatic brain injury.<br /><br />TBI is the disruption (often temporary) of normal brain function caused by a jolt or blow to the head, and the military population is especially susceptible. Nearly 459,000 service members worldwide were diagnosed with a first-time TBI from 2000 through the first quarter of 2022, according to the Department of Defense. Concussion—also known as mild TBI—accounts for over 80% of these, making it by far the most common type of active-duty TBI. <br /><br />But a diagnosis requires a medical exam. With a population that has volunteered to put their lives on the line to protect and defend, it may be tempting to prioritize the mission over medicine, downplaying or ignoring any symptoms. Retired U.S. Marine Corps Capt. William Greeson, who was treated for brain injury at the end of a long military career, says this attitude is especially true for what he calls “military alphas.”<br /><br />“[Their attitude is] ‘I’m going to go out front, I’m going to lead, I’m going to get it done, and we&#39;ll talk about this later,’ ” he said. “And then later never comes.”<br /><br />At the Military Health System’s Traumatic Brain Injury Center of Excellence, we believe later should come sooner. With that in mind, let’s clear up some myths about the most common type of TBI. Can you separate fact from fiction in the following statements? <br /><br />Concussions only happen on the battlefield.<br />False. About 8% of active-duty concussions are from battle injuries, and only 20% happen during deployment. The rest are sustained while doing things like playing contact sports, participating in military training, or crashing a vehicle.<br /><br />You don’t have to get “knocked out” to have a concussion. <br />True. Concussions temporarily change how the brain works. This can be a brief loss of consciousness. More often, consciousness is altered, such as, being dazed or seeing stars, or unaffected.<br /><br />You can have a concussion even without a blow to the head. <br />True. A concussion may be caused by a sudden increase or decrease in speed, even if the head doesn’t strike anything. For example, the external forces present in cases of whiplash or blast injury may be strong enough to shake the brain, causing it to hit the skull and leading to potential damage. <br /><br />If you don’t have a headache, you’re fine. <br />False. A headache is the most common symptom of concussion, but it’s just one of many. Concussion symptoms can be physical, cognitive, or emotional, causing a wide variety of issues such as irritability, fatigue, balance difficulties, sleep disturbance, dizziness, ringing in the ears, blurred vision, and concentration or memory difficulties. Some symptoms are warrant a trip to your local emergency department. These include: <br /> <br />• Worsening headache <br />• Slurred speech or difficulty speaking<br />• Unsteadiness on feet <br />• Seizures <br />• Double or blurred vision <br />• Weakness or numbness anywhere in your body <br />• Decreasing levels of alertness <br />• Disorientation (not knowing where you are, difficulty recognizing people or places)<br />• Any unusual behavior (such as increased aggression, anger, irritability, or crying)<br />• Repeated vomiting <br />• Feeling that something “just isn’t right” <br /> <br />Symptoms of a concussion appear immediately after the injury. <br />False. Concussion symptoms can start immediately after the injury—or gradually over the next 48 hours. The good news is that they often resolve within days or weeks. <br /><br />Most people fully recover from a concussion, particularly if it’s their first. Service members can usually return to full duty in 2–4 weeks.<br />However, the time it takes to heal depends on the individual, the nature of the injury, any history of concussions or migraines, and associated conditions such post-traumatic stress disorder, depression, anxiety, and substance-use disorder. <br /><br />You should seek medical care and follow your doctor’s progressive return to activity guidance because a concussion can impact memory, concentration, coordination, reaction time, and other areas—that may affect job performance or unit readiness and safety. This is also why you must be medically cleared before picking up that basketball or your car keys; otherwise, symptoms like dizziness, balance problems, and fatigue can put you at risk of re-injury. <br /><br />Visit <a target="_blank" href="https://rly.pt/TBICoE">https://rly.pt/TBICoE</a> for more information about all types of TBI, as well as provider resources and support for service members, veterans, families, and caregivers. <div class="pta-link-card answers-template-image type-default"> <div class="pta-link-card-picture"> <img src="https://d1ndsj6b8hkqu9.cloudfront.net/link_data_pictures/images/000/745/185/qrc/open-uri20221003-10507-1dq6vra"> </div> <div class="pta-link-card-content"> <p class="pta-link-card-title"> <a target="blank" href="https://rly.pt/TBICoE">Traumatic Brain Injury Center of Excellence</a> </p> <p class="pta-link-card-description">TBICoE unifies a system of TBI health care, reliably advancing the science for the warfighter and ready to meet future brain health challenges.</p> </div> <div class="clearfix"></div> </div> Mon, 03 Oct 2022 12:23:49 -0400 What You Should Know About Concussions https://www.rallypoint.com/command-post/what-you-should-know-about-concussions <div class="images-v2-count-1"><div class="content-picture image-v2-number-1" id="image-724952"> <div class="social_icons social-buttons-on-image"> <a href='https://www.facebook.com/sharer/sharer.php?u=https%3A%2F%2Fwww.rallypoint.com%2Fanswers%2Fwhat-you-should-know-about-concussions%3Futm_source%3DFacebook%26utm_medium%3Dorganic%26utm_campaign%3DShare%20to%20facebook' target="_blank" class='social-share-button facebook-share-button'><i class="fa fa-facebook-f"></i></a> <a href="https://twitter.com/intent/tweet?text=What+You+Should+Know+About+Concussions&amp;url=https%3A%2F%2Fwww.rallypoint.com%2Fanswers%2Fwhat-you-should-know-about-concussions&amp;via=RallyPoint" target="_blank" class="social-share-button twitter-custom-share-button"><i class="fa fa-twitter"></i></a> <a href="mailto:?subject=Check this out on RallyPoint!&body=Hi, I thought you would find this interesting:%0D%0AWhat You Should Know About Concussions%0D%0A %0D%0AHere is the link: https://www.rallypoint.com/answers/what-you-should-know-about-concussions" target="_blank" class="social-share-button email-share-button"><i class="fa fa-envelope"></i></a> </div> <a class="fancybox" rel="8de3c4980110145aed2baba94b684bc2" href="https://d1ndsj6b8hkqu9.cloudfront.net/pictures/images/000/724/952/for_gallery_v2/2daf7d12.jpg"><img src="https://d1ndsj6b8hkqu9.cloudfront.net/pictures/images/000/724/952/large_v3/2daf7d12.jpg" alt="2daf7d12" /></a></div></div>By USPHS CAPT Tricia Booker <br />Traumatic Brain Injury Center of Excellence <br /><br />Having your bell rung. Getting knocked out. Seeing stars. <br /><br />You might use one of those terms to describe a hard hit to your head. But your doctor might call it something else: a possible traumatic brain injury.<br /><br />TBI is the disruption (often temporary) of normal brain function caused by a jolt or blow to the head, and the military population is especially susceptible. Nearly 459,000 service members worldwide were diagnosed with a first-time TBI from 2000 through the first quarter of 2022, according to the Department of Defense. Concussion—also known as mild TBI—accounts for over 80% of these, making it by far the most common type of active-duty TBI. <br /><br />But a diagnosis requires a medical exam. With a population that has volunteered to put their lives on the line to protect and defend, it may be tempting to prioritize the mission over medicine, downplaying or ignoring any symptoms. Retired U.S. Marine Corps Capt. William Greeson, who was treated for brain injury at the end of a long military career, says this attitude is especially true for what he calls “military alphas.”<br /><br />“[Their attitude is] ‘I’m going to go out front, I’m going to lead, I’m going to get it done, and we&#39;ll talk about this later,’ ” he said. “And then later never comes.”<br /><br />At the Military Health System’s Traumatic Brain Injury Center of Excellence, we believe later should come sooner. With that in mind, let’s clear up some myths about the most common type of TBI. Can you separate fact from fiction in the following statements? <br /><br />Concussions only happen on the battlefield.<br />False. About 8% of active-duty concussions are from battle injuries, and only 20% happen during deployment. The rest are sustained while doing things like playing contact sports, participating in military training, or crashing a vehicle.<br /><br />You don’t have to get “knocked out” to have a concussion. <br />True. Concussions temporarily change how the brain works. This can be a brief loss of consciousness. More often, consciousness is altered, such as, being dazed or seeing stars, or unaffected.<br /><br />You can have a concussion even without a blow to the head. <br />True. A concussion may be caused by a sudden increase or decrease in speed, even if the head doesn’t strike anything. For example, the external forces present in cases of whiplash or blast injury may be strong enough to shake the brain, causing it to hit the skull and leading to potential damage. <br /><br />If you don’t have a headache, you’re fine. <br />False. A headache is the most common symptom of concussion, but it’s just one of many. Concussion symptoms can be physical, cognitive, or emotional, causing a wide variety of issues such as irritability, fatigue, balance difficulties, sleep disturbance, dizziness, ringing in the ears, blurred vision, and concentration or memory difficulties. Some symptoms are warrant a trip to your local emergency department. These include: <br /> <br />• Worsening headache <br />• Slurred speech or difficulty speaking<br />• Unsteadiness on feet <br />• Seizures <br />• Double or blurred vision <br />• Weakness or numbness anywhere in your body <br />• Decreasing levels of alertness <br />• Disorientation (not knowing where you are, difficulty recognizing people or places)<br />• Any unusual behavior (such as increased aggression, anger, irritability, or crying)<br />• Repeated vomiting <br />• Feeling that something “just isn’t right” <br /> <br />Symptoms of a concussion appear immediately after the injury. <br />False. Concussion symptoms can start immediately after the injury—or gradually over the next 48 hours. The good news is that they often resolve within days or weeks. <br /><br />Most people fully recover from a concussion, particularly if it’s their first. Service members can usually return to full duty in 2–4 weeks.<br />However, the time it takes to heal depends on the individual, the nature of the injury, any history of concussions or migraines, and associated conditions such post-traumatic stress disorder, depression, anxiety, and substance-use disorder. <br /><br />You should seek medical care and follow your doctor’s progressive return to activity guidance because a concussion can impact memory, concentration, coordination, reaction time, and other areas—that may affect job performance or unit readiness and safety. This is also why you must be medically cleared before picking up that basketball or your car keys; otherwise, symptoms like dizziness, balance problems, and fatigue can put you at risk of re-injury. <br /><br />Visit <a target="_blank" href="https://rly.pt/TBICoE">https://rly.pt/TBICoE</a> for more information about all types of TBI, as well as provider resources and support for service members, veterans, families, and caregivers. <div class="pta-link-card answers-template-image type-default"> <div class="pta-link-card-picture"> <img src="https://d1ndsj6b8hkqu9.cloudfront.net/link_data_pictures/images/000/745/185/qrc/open-uri20221003-10507-1dq6vra"> </div> <div class="pta-link-card-content"> <p class="pta-link-card-title"> <a target="blank" href="https://rly.pt/TBICoE">Traumatic Brain Injury Center of Excellence</a> </p> <p class="pta-link-card-description">TBICoE unifies a system of TBI health care, reliably advancing the science for the warfighter and ready to meet future brain health challenges.</p> </div> <div class="clearfix"></div> </div> Tricia Booker Mon, 03 Oct 2022 12:23:49 -0400 2022-10-03T12:23:49-04:00 Response by SFC David Reid, M.S, PHR, SHRM-CP, DTM made Oct 3 at 2022 12:40 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7909931&urlhash=7909931 <div class="images-v2-count-0"></div>For sometime, these type of injuries were not discussed and or highlighted. As lovers of football, our minds somewhat focuses just on our favorite teams. But this message helps us more to understand the impact of these injuries. The NFL has stepped in an developed protocols. Other sports such as the NBA has also defined fouls as flagrant or not. If the fouls are determined to be flagrant players are removed from playing and fined. SFC David Reid, M.S, PHR, SHRM-CP, DTM Mon, 03 Oct 2022 12:40:57 -0400 2022-10-03T12:40:57-04:00 Response by SFC David Reid, M.S, PHR, SHRM-CP, DTM made Oct 3 at 2022 12:46 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7909945&urlhash=7909945 <div class="images-v2-count-0"></div>Also, the NFL surveys equipment such as helmets to insure that they aid in avoiding severe injuries to the head. SFC David Reid, M.S, PHR, SHRM-CP, DTM Mon, 03 Oct 2022 12:46:43 -0400 2022-10-03T12:46:43-04:00 Response by MSG Private RallyPoint Member made Oct 3 at 2022 1:05 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7909974&urlhash=7909974 <div class="images-v2-count-0"></div>Disclaimer: If you looked like Tua Tagovailoa last week (posturing), you might have a concussion. MSG Private RallyPoint Member Mon, 03 Oct 2022 13:05:14 -0400 2022-10-03T13:05:14-04:00 Response by SFC Jim Ruether made Oct 3 at 2022 5:30 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7910441&urlhash=7910441 <div class="images-v2-count-0"></div>I think there are many more concussions on the playing field then just the reciever that takes a hard hit. Those linemen live day in and day out with hard hits. SFC Jim Ruether Mon, 03 Oct 2022 17:30:11 -0400 2022-10-03T17:30:11-04:00 Response by SFC Casey O'Mally made Oct 3 at 2022 11:58 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7910999&urlhash=7910999 <div class="images-v2-count-0"></div>Think you have a concussion? It&#39;s all in your head. SFC Casey O'Mally Mon, 03 Oct 2022 23:58:07 -0400 2022-10-03T23:58:07-04:00 Response by SSgt Richard Kensinger made Oct 4 at 2022 10:45 AM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7911713&urlhash=7911713 <div class="images-v2-count-0"></div>The concussive injuries in combatants is far more serious than those in collision sports like American football, boxing and hockey.<br />Combatants also exhibit increased suicidal risk, complex PTSD, mixed substance abuse and profound moral injuries.<br />Rich SSgt Richard Kensinger Tue, 04 Oct 2022 10:45:39 -0400 2022-10-04T10:45:39-04:00 Response by LTC David Salvadorini made Oct 5 at 2022 1:19 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7913656&urlhash=7913656 <div class="images-v2-count-0"></div>Make the MRI more friendly and avoid sedation or claustrophobia. <a target="_blank" href="http://www.Cinemavision.biz">http://www.Cinemavision.biz</a> <div class="pta-link-card answers-template-image type-default"> <div class="pta-link-card-picture"> <img src="https://d1ndsj6b8hkqu9.cloudfront.net/link_data_pictures/images/000/745/625/qrc/open-uri20221005-7476-ct5x38"> </div> <div class="pta-link-card-content"> <p class="pta-link-card-title"> <a target="blank" href="http://www.Cinemavision.biz">Cinemavision</a> </p> <p class="pta-link-card-description">Reduce Sedation</p> </div> <div class="clearfix"></div> </div> LTC David Salvadorini Wed, 05 Oct 2022 13:19:25 -0400 2022-10-05T13:19:25-04:00 Response by CPT Stephen Feldman made Oct 5 at 2022 1:53 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7913699&urlhash=7913699 <div class="images-v2-count-0"></div>I suffered a TBI when I was hanged outside a C-130 almost 47 years ago. I hit my head on the step and knocked myself out. Today, I still suffer some of the problems that developed from that concussion. The other problems suffered from hitting the plane resulted in a medical discharge with 16 years of service and over 19 operations over the years. But the concussion, in my opinion, has been the most impactful to my life. CPT Stephen Feldman Wed, 05 Oct 2022 13:53:06 -0400 2022-10-05T13:53:06-04:00 Response by SrA Travis Ebmeyer made Oct 5 at 2022 3:02 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7913827&urlhash=7913827 <div class="images-v2-count-0"></div>The whole getting the proper care is a process. Starts with a psychiatrist, then mri, ptsd treatment and then hopefully(at least this is were i am now at in the process) tbi care at the shepherd center? Some of the other places are 1- 1.5 yrs out. SrA Travis Ebmeyer Wed, 05 Oct 2022 15:02:55 -0400 2022-10-05T15:02:55-04:00 Response by CMSgt Elbert E. Clayton made Oct 5 at 2022 6:17 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7914202&urlhash=7914202 <div class="images-v2-count-0"></div>Last month, at age 83 plus, I suffered my second &quot;syncope&quot; episode (no. 1 was four years ago). Both times I fainted and fell in the exact same place and fractured ribs and knees. I have also had multiple other problems from two tours in Vietnam. PTSD and Agent Orange afflictions (Diabetes, Prostate Cancer, High Blood Pressure, Blood Sugar control, etc.). After the latest fainting episode and a three-day hospital stay, my heart Physician prescribed multiple full body X-Rays, and Scans, etc. Nothing was found as causative of the recent &quot;Syncope&quot; episodes, but he did find evidence of a previous &quot;Stroke&quot; years ago. I cannot remember ever having any stroke in my entire life. However, after reading the above Rallypoint information post, I have remembered an incident which occurred in late 1962, in the &quot;Cholon&quot; district of Saigon. Cholon was well known at the time as unsafe but especially so at night (it became Viet Cong territory). Unfortunately, about 4 or 5 USAF enlisted members, including myself, visited a bar there and were enjoying ourselves with a few beers. Needing to go to the bathroom, I excused myself and walked towards the rear of the bar. The entrance to the men&#39;s and women&#39;s area was covered with a long length Beaded Curtain. As I stepped through this beaded doorway, I was struck just over my right eyebrow with some very heavy object which slit my eyebrow and knocked me unconscious for several minutes. My friends missed me after about 15 minutes and came looking for me. They found me and rushed me to the Tan Son Nhut AB by taxi and I received a few stitches and returned to work the next morning around 0400 as usual. I will relate this to my Physician tomorrow. I will also start wearing a Heart Monitor for the next thirty days next week per my physician&#39;s direction. I post this to thank RallyPoint for the information. CMSgt Elbert E. Clayton Wed, 05 Oct 2022 18:17:01 -0400 2022-10-05T18:17:01-04:00 Response by SGT Thomas Seward made Oct 6 at 2022 1:27 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7915781&urlhash=7915781 <div class="images-v2-count-0"></div>In 1982, at Ft McClellan, I got a skull fracture, stitches on my scalp, and broke C3 - C7. I’m guessing that was a TBI.<br />It took me almost 20 years to get the record of the injury, as there was nothing in my medical records. I finally asked for the actual hospital records from the closed hospital and got a one page ER doctors hand written notes showing the injuries. SGT Thomas Seward Thu, 06 Oct 2022 13:27:41 -0400 2022-10-06T13:27:41-04:00 Response by CPL Brian Prosser made Oct 6 at 2022 3:18 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7915959&urlhash=7915959 <div class="images-v2-count-0"></div>I believe that I have breachers syndrome. I was a Mortarman when I was in and experienced thousands of rounds going down range. How do I get checked CPL Brian Prosser Thu, 06 Oct 2022 15:18:03 -0400 2022-10-06T15:18:03-04:00 Response by LCpl Stanley Wilcox made Oct 6 at 2022 7:45 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7916338&urlhash=7916338 <div class="images-v2-count-0"></div>Is there a test that can be taken to know if you have ever had a TBI? Can LCpl Stanley Wilcox Thu, 06 Oct 2022 19:45:11 -0400 2022-10-06T19:45:11-04:00 Response by SP5 Dennis Loberger made Oct 7 at 2022 1:42 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=7917787&urlhash=7917787 <div class="images-v2-count-0"></div>I boxed and played football when I was younger. I definitely had a concussion boxing. Just waiting for the problems to develop SP5 Dennis Loberger Fri, 07 Oct 2022 13:42:57 -0400 2022-10-07T13:42:57-04:00 Response by SrA Private RallyPoint Member made Jul 27 at 2023 5:50 PM https://www.rallypoint.com/command-post/what-you-should-know-about-concussions?n=8393100&urlhash=8393100 <div class="images-v2-count-0"></div>I was actually checked for TBI at the VA and they decided that I don&#39;t have it but what I have had throughout my life is 1 too many concussions. That&#39;s what happens when you&#39;re a big guy trying to work on Jets (you don&#39;t fit) in small cramped or compartmentalized spaces - heck I don&#39;t even fit in most vehicles.<br /><br />I&#39;m 6&#39; 8&quot; 320 LBS but my 2 most recent concussions came from trying to lose weight swimming the back stroke at the REC center I was 340 and have been slowly losing the weight, I ran my head into the pool wall (twice) 5 days apart. I ended up with a pinched nerve in my neck, I was angry all the time for 2 weeks.<br /><br />It was like there was no off switch for all of the pain that I was feeling, I was irritable and it was a huge wake up call when my sweet wife told me that I was scaring her and she wanted to go stay with her friend.<br /><br />I went to the Chiropractor and he is the one that adjusted the pinched nerve, and he also adjusted my face, he said that alignment was off too - before he did this, I kid you not I was unable to smile. Minutes after the adjustment, he was like &quot;there you are, we missed you. Welcome back!&quot; The way he described it he told me that there is this Halo at the top of your spine that controls how much pain your body gives to you - he told me that my pinched nerve was holding this Halo open so that my body was giving me all of the pain that it could 24/7 until he adjusted it. <br /><br />I had a CT but after a few weeks passed I was still in immense pain so I had an MRI - the one at the Department of Veterans Affairs was so old I felt like Hannibal Lecter with the mask/headgear they make you wear in order to stay still.<br /><br />The guy &quot;Jim&quot; at the VA brought me a gown to put on, and while I was still trying to tie it he brought me another gown and said to me &quot;This one is for overweight people!&quot; I was retelling this story later to my Folks and my Mom was like &quot;Did you say something to him?!&quot; No, I said. He wasn&#39;t worth my time.<br /><br />Instead I just took it, thanked him and asked him to please tie it in the back.<br /><br />They found nothing wrong - but I still feel residual effects from said concussion and I got those last 2 at the end of April, 2023. <br /><br />Always pay attention to how you feel - and please, please don&#39;t be afraid to ask someone for help! SrA Private RallyPoint Member Thu, 27 Jul 2023 17:50:42 -0400 2023-07-27T17:50:42-04:00 2022-10-03T12:23:49-04:00