Storyboard Your Educational Videos

Resus Review

Videos for medical education have moved way beyond videotaped chalkboard lectures. The badly light, noisy audio, and monotone lectures will not be missed. Medical education at every level (medical school, resident, and continuing medical education) is adopting new techniques. Video is critical for interactive-learning and in flipped classrooms. Students are more engaged when video is used, and retain more of what they are taught. Students have come to expect high production values, and this is a challenge for the educators making the videos.

Storyboard Your Education Videos

There are myriad ways video is being used:

  • Teaching concepts
  • Demonstrate procedures
  • Introduce simulation scenarios
  • Patient education
  • Screencast lectures
  • Recording online meetings

Producing High Quality Video

The best of the videos being made today are professional, educational, moving, and creative. We are all inspired by TED and Kahn Academy, and strive to produce videos that are dynamic and can hold an audience’s attention while simultaneously educating them. The are storytelling at its best. This level of professionalism, requires a large investment. Not necessarily of money. Professional quality audio and video recording equipment, editing software, graphics, storage, and distribution, have plummeted in price and are widely available.

What educators often find they lack is the expertise need to use these tools to the level they desire. We have been trained as physicians. Some have sought out additional training in education, but audio-video production is its own profession that has its own vocabulary, grammar, and techniques. Things people spend careers learning and perfecting, just as we do as doctors.

As physician educators we may not have the spare time to invest. If this is the case, seeking out expertise for help is perfectly acceptable. But it is still your responsibility to design the education content. To define the educational objectives, design the instruction and teaching method, and create and refine your content. These are done before any recording or editing is started.

Defining Objectives for Your Lesson

The process should with defining the list of educational objectives for the content. This should be 4-5 items. I find it useful to place them in ascending learning level. For example, objective 1 should be achieved by all learners and objective 5 would be met only by the advanced students. The ACGME has encouraged the use of milestones in residency education, which can serve as a framework for our educational project. Well thought out objectives though, can focus the rest of the work.

I like to image the content creation cycle. It begins with an idea and the educational objectives you have defined. We usually need to research the topic and review the latest literature. Next we create and outline and write the script. This can then storyboarded, which allows us to record, edit, and share the video.

Content Creation Cycle

Content Creation Cycle

There are a large number of forms your teaching session can take. In a previous post we discusseed a number of options for a flipped classroom.

Using Storyboards

If you have decided to incorporate video, it is critical to plan the video. Shooting, editing, recording audio, producing graphics is very time-consuming and expensive, so planning the video helps you define your video. It tells everyone what shots will be required, what graphics are needed.

I have found that the best way to do this is by storyboarding your video, after the objectives have been defined and the content material developed. The idea of storyboarding and techniques were originally created by Walt Disney. A storyboard allows you to plan how you will visually tell your story. This allows the scope the production before picking up the camera.

The important thing about storyboards is that they give you a way to decide how you will split up your script into individual segments, either with or without placeholder images, so that you can then get a clearer overview of your digital story plan. It is the equivalent of creating an outline for paper or blog post.

Creating storyboards may seem like a tedious extra step. However, storyboarding can be a valuable component in the creative process by allowing you to organize images and text in a blueprint fashion. It allows you to visualize how the project will be put together and help illustrate what holes exist since you can see the entire plan laid out in front of you. Storyboarding can also inspire new ideas as well as lets you easily rearrange existing resources before the final development begins and changes would be harder to make.

Storyboards may be created in a variety of ways, both digitally and manually on paper. You can use a computer, iPad, notecards, notebook, or even loose leaf copier paper. I personally favor digital storyboarding, and am a fan of using Paper on iPad. But there is really no restrictions on how you work.

A storyboard is a sequential description of the elements of the story such as images, text, narration, music, transitions, shots. They are arranged in in the chronological order in which they will appear in the story.

Things to include in your storyboard:

  • Boxes are read left-to-right.
  • In each box draw the basic composition. Art is not the key here. Sick figures are fine.
  • Key props should be included.
  • Indicate camera changes — pan, zoom in/out, focus rack
  • Blocking (position and movement of the actors) should be indicated.
  • Changes between shots (eg jump cuts, fades) should be indicated if important to the storytelling
  • As the story becomes more developed, I find it useful to add notes for music cues, sound effects, and ambient noise.

Since the storyboard is a visual plan for your film, it useful to become familiar with the basic language used in film.

  • Understand the different kinds of shorts. Long shot (also called an establishing shot since it lets audiences see the whole scene), medium shot, close up. There are variations in between, but each shot conveys its own king of emotion and action. It is a general rule that when cutting between shots, that you should not have two of the same type in a row
  • For every action shot, you should also film a reaction shot.
  • Avoid panning like crazy. In a single shot, you should not pan in more than one direction as it can be quite disconcerting to the audience. This is the reason I think Prezi did not catch on. While the idea was interesting, the zoom in/out and all around caused too much distraction.
  • Shoot to edit. Fast paced news recording generally shoot shots in sequence. Boy walks up to balloon stand, close of boy’s face looking at the balloons, medium shot of boy paying, close up of money exchanging hands, medium shot of seller handing the balloon to the boy, etc. Unfortunately, this is not always the most efficient way of getting all the shots and duplicates setups. If your have thought through your storyboard, you can plan the shots out of order and edit them together afterwards.

Example Storyboard

As an example, the gallery below is an early storyboard for a video demonstrating the use of a Minnesota Tube.

EVO-Competition-MN-Tube-Storyboard-1 EVO-Competition-MN-Tube-Storyboard-2 EVO-Competition-MN-Tube-Storyboard-3 EVO-Competition-MN-Tube-Storyboard-4 EVO-Competition-MN-Tube-Storyboard-5 EVO-Competition-MN-Tube-Storyboard-6 EVO-Competition-MN-Tube-Storyboard-7 EVO-Competition-MN-Tube-Storyboard-8 EVO-Competition-MN-Tube-Storyboard-9

Share your tips for producing educational videos.

Storyboard Your Educational Videos

ARVD diagnosis and advanced treatment

Resus Review

Arrhythmogenic right ventricular dysplasia (ARVD, now also called ARVC for arrhythmogenic right ventricular cardiomyopathy) is an inherited cardiomyopathy. It is inherited in an autosomal dominant pattern with variable penetrance. It can be found in 1:1000 of the population, and is a significant cause of sudden cardiac death in young athletes.

The normal myocardium of the right ventricle becomes replaced by a chaotic mix of fibrous tissue and fat interspersed within myocardium. The myocardium becomes extremely thinned. The left ventricular may also be involved, but often to a lesser extent. These pathologic changes usually become evident by the time the patient is 20-30 years old.

The effect of these morphologic changes is right ventricular failure and rhythm abnormalities. Ventricular tachycardia and ventricular fibrillation is common, and unfortunately can result in sudden cardiac death (SCD). Structural remodelling of the myocardial wall progresses with the course of the disease, and this generates more and more foci for initiating arrhythmias.

The diagnosis can be challenging due to nonspecific clinical features. It is important to gather structural, functional, and electrophysiologic information about the patient’s heart to make the diagnosis. The first diagnostic criteria were laid out in 1994 by the International Task Force, and revised in 2010. However, it is usually arrhythmia (especially ventricular tachycardia), that first brings the healthy patient medical attention.

Simplified diagnostic criteria of ARVD (2 required). Adopted from Circulation 2010;121:1533.

  • Structural. Regional RV akinesia, dyskinesia, or aneurysm with either dilated RVOT or decreased EF by echo, MRI, or angiography.
  • Tissue. Residual myocytes <50% of RV free wall by biopsy.
  • Repolarization abnormalities. Inverted T waves in the right precordial leads (V1-v#) in the absence of complete RBBB
  • Depolarization/conduction abnormalities. Epsilon wave in the right precordial leads (V1 – V3)
  • Arrhythmias. Nonsustained or sustained ventricular tachycardia of LBBB morphology with superior axis.
  • Family history. First degree relative diagnosed with ARVD.

The ECG changes in ARVD include:

  • Epsilon wave (most specific finding, seen in 30% of patients). From Slow RV.
  • Epsilon wave seen in ARVD

  • T wave inversions in V1-3 (85% of patients)
  • Prolonged S-wave upstroke of 55ms in V1-3 (95% of patients)
  • ARVD ECG T Wave Inversion

  • Localised QRS widening of 110ms in V1-3
  • Paroxysmal episodes of ventricular tachycardia with a LBBB morphology

Therapies are directed at preventing heart failure, malignant arrhythmias, and sudden cardiac death. Treats can include:

  • Avoid strenuous sports and activity.
  • ICD implantation after episode of sustained VT.
  • Class III antiarrhythmic (sotalol, amiodarone) therapy if there are unacceptable number of ICD discharges.
  • Consideration of radiofrequency ablation (RFA).
  • Bilateral cardiac sympathetic denervation via thoracoscopy if refractory to all other therapy
  • Heart transplantation

Conventional treatment begins with avoidance of high-intensity activity that can precipitate arrhythmias. ICD implantation is recommended once evidence of ventricular tachycardia has occurred for the patient. Medical antiarrhythmic therapy is usually added as the disease progresses and the ICD discharges are either intolerable or unsuccessful.

If patients are not tolerate of antiarrhythmic treatment or do not achieve unsuccesful clinical improvement, RFA has been the standard backup therapy. However, because of the progressive nature of the disease, even if the original arrhythmia foci are ablated, further remodelling can produce additional initiated sites. Recurrence rates of ventricular arrhythmias after RFA are 50-75% after ablation.

Standard ablation is performed by transvenous approach and performed on the endocardial surface. However, patient’s have a higher success rate for RFA if ablation is performed on epicardial foci also. This requires pericardial access, usually obtained percutaneously with a micropuncture needle. Once confirmed that the pericardial space has been entered, and that there are not interfering adhesions, the tract can de dilated for a sheath insertion. The mapping and ablation catheter can then act on the epicardial surface of the heart. With this endo-epicardial combined approach, there are reports that up to 85% of patients may remain free of arrhythmias.

End-stage heart failure or refractory arrhythmias may require that the patient is considered for heart transplantation.

ARVD diagnosis and advanced treatment

Helping Patients Navigate the Emergency Department

Resus Review

Patients come to the department because the are hurt, suffering, confused, feeling ill, or scared. This is usually their first visit seeking emergency care, and can be overwhelmed by the system. One of the keys to providing patient centered care is inform them as much as possible about the what to expect and what is going on while they are in the emergency department.

Helping Patients Navigate the Emergency Department

Understanding the process comforts the patient that they are actively being cared for, and not forgotten. This can be done in many ways. It occurs during every personal interaction, at transitions of care, and periodically during the visit.

One way to augment this communication, is to providing written material to the patient with basic information. The letter below is a sample of what can be provided to an emergency department patient to help them understand the emergency department and what to expect.

To Patients and Visitors of Our Emergency Department

Visiting an emergency department is an unexpected and stressful experience. Our team in the Emergency Department are highly trained to provide the care you need no matter what the problem, on an unscheduled basis, without an appointment, irrespective of the ability to pay.

We want you to understand how you will be cared for during your visit.

Our Emergency Department offers 3 distinct services to appropriately meet your needs. These services are:

  • Urgent Care. As the name suggests, this area of the Emergency Department is designed to provide rapid care for non-life threatening illnesses and injuries. Theese services are available 7 days a week from 7 am to 10 pm.
  • Emergency Department. Equipment and services to treat stable, urgent and emergent illnesses and injuries are available 24 hours a day.
  • Stabilization Center. Capabilities include specialized emergency resuscitation, diagnostic, surgical and critical care services that are specifically organized for immediate response to provide care and treatment for patients with immediate life-threatening problems.

Triage

Your treatment begins at this point. In the Emergency Department, it is extremely important that the most critically ill and injured patients are seen first. This process is called “triage”. The triage nurse will:

  • Confirm the reason for your visit, your name and birth date.
  • Ask about any medications you are taking and any allergies you may have.
  • Obtain a brief medical history.
  • Take your vital signs: blood pressure, pulse, respiration and temperature.
  • Assess the urgency of your condition.
  • Some patients may have preliminary tests or x-rays done.
  • Basic treatments for pain, fever, shortness of breath may be started if indicated.
  • If your doctor referred you to the Emergency Department, the Triage Nurse will still have to determine the urgency of your condition. Even if your doctor has phoned ahead, you may have to wait if there are more urgent patients requiring treatment.

It is very important that you notify the triage nurse if your condition changes at any point while you are waiting.

Consult the triage nurse before eating or drinking as it may affect your treatment plan.

How long will I wait?

Waiting times depend on the seriousness of your condition and the condition of the other patients waiting for care. We take care of patients with the most serious problem first. Staff can only approximate waiting time, and this may change as additional patients arrive. Our promise is to speed your treatment as much as possible, and always keep you informed of the process.

Who will I see while in the Emergency Department

You will meet many people during your visit to the emergency department. These include:

  • Nurses
  • Physicians
  • Residents and medical students
  • Radiology Technicians
  • Lab Technicians
  • Healthcare Assistants
  • Paramedics
  • Security Officers
  • Clerks

Everyone who visits you should introduce themselves and clearly state their role in your care. A badge with this information should be prominently visible. If at anytime you are unclear who someone is or what their role is, please ask.

Registration

During the registration process, the clerk will ask you a number of demographic questions (address, phone number, emergency contacts) for your record and obtain a signature for consent for us to treat you. Also, you will be asked for insurance information if available.

All patients, regardless of ability to pay or insurance status are treated.

Emergency Department Treatment Area

Once you are taken into an exam room, you will be assigned a primary care nurse. He/she may initiate certain treatments based upon your condition, including drawing blood, placing an intravenous (IV) catheter, or checking your heart rate, blood pressure or oxygen level.

You may be initially seen by a resident or medical, who will obtain a detailed history and perform a physical exam. As needed, additional tests or treatments may be ordered at that time.

All of your care will directed by the the supervising emergency physician attending who will also examine you and discuss your problem with you.

Tests and Treatments

Tests and treatments assist the physician in determining the appropriate plan of care for you. Lab results typically take 1-2 hours, depending on the type of test.

X-rays may be ordered. Some radiology studies, such as CT scans, may require that you drink contrast in either juice or water. To ensure accurate results, you may be required to wait up to 4 hours.

Some patients will have cardiogram/EKG which will be shown to the ED physician within 10 minutes of its completion.

You will be informed throughout all stages of assessment and treatment.

After your results have been completed, we will develop a plan of care with you. This plan of care will be discussed with you in detail. We encourage you to ask questions regarding your care at any time. Some illnesses and injuries may require you to be admitted to the hospital or to follow-up with a physician in the office. If at any time you are concerned about treatment or delays, please ask your nurse or doctor.

Leaving the Emergency Department

You will be given instructions prior to leaving the Emergency Department. Items include:

  • Name of the physician or nurse practitioner who treated you.
  • List of any new medications or changes to previous medications.
  • Information on your condition.
  • Who, when, and where to follow up with.

If you do not understand any of the instructions, please ask us. If questions arise once you get home, please call the Emergency Department at (XXX) XXX-XXXX or follow-up with your primary care physician.

Admission to the Hospital

Some conditions and treatments may require you to be admitted to the hospital. While the hospital prepares a room for you, you will wait in the Emergency Department. The wait time will depend on the type of bed you need. While you are still in the emergency department, you will continue to be cared for by the staff. This includes any needed treatments, evaluations, and comfort.

Privacy

Your privacy and confidentiality is a vital component of showing you respect. Your condition and medical information will only be available to those who need to know the information as part of your care.

We expect that patients, friends and family respect the privacy of others as well.

Visitors

We understand and support the need for family and friends in the Emergency Department. At times, we must limit visitation in order to provide quality care in a private and safe environment. Patients may be limited to two visitors at the bedside. While visiting, please remain in the patient’s room.
Depending on current activities in the Emergency Department, it may not be appropriate for children to visit. Adult supervision of children is required at all times.

Security

Your personal security is a basic expectation while you are in the emergency department. Our campus security officers and peace officers are a visible and dedicated to providing a safe place for you to receive care. Protecting patients does require verifying identities of visitors and obtaining passes.

We strongly recommend that all money and valuables be sent home with family or friends.

Escorts are available from the hospital to your vehicle.

Food

Patients who are awaiting treatment should not eat or drink anything until cleared by the healthcare team, as it may worsen their condition or delay therapy.

Food is available for friends and family, in the cafeteria. It is located on the second floor. Any staff member will be happy to direct you. Vending machines are also available in the Emergency Department lobby for your convenience. The coffee shop is located just off the main hospital lobby.

Cell Phones

We understand that communication with loved ones is important during emergency situations. Cell phones are permitted in the Emergency Department. We ask that you respect others while using your phone by speaking in a low volume.

Your Satisfaction

We appreciate hearing concerns regarding your visit to the emergency department. Patient satisfaction is very important to us. If you would like to discuss any aspect of your care while in the emergency department, I want to hear from you.

Dr Emergency Physician
Chair, Department of Emergency Medicine
City Hospital
Anywhere, USA

What has worked well with the patients in your emergency department?

Helping Patients Navigate the Emergency Department

Pacemaker Lead failure

Resus Review

Pacemaker externalized

Placement of ICD/Pacemakers have become a very safe procedure. Nevertheless, acute and long-term complications can be seen.

Lead Complication
* Acute perforation
* Dislodgement
* Infection
* Vein thrombosis
* Migration
* Conduction failure
* Insulation damage
* Externalization

This problem was faced by St. Jude Medical for there Riata silicone-insulated leads, and led to a physician advisory. These events usually showed up 4-5 years after implantation and was diagnosed either in asymptomatic patients undergoing routine imaging, or more commonly as changes in conduction and electrical conduction. The most common site was the part of the lead just below the tricuspid valve.

ICD Lead Externalized Wire

Drawing of pacemaker/ICD lead with externalized wire

Unfortunately, recommendations for interval of screening and long-term follow up are not defined. Routine removal of the leads is not recommended.

ICD Lead Externalized Wire on Fluoroscopy

Fluoroscopy image of failed Pacemaker ICD Lead with externalized wire

============

Fluoroscopic screening has been performed to evaluate externalization of the recalled Riata leads, and has been demonstrated to have positive and negative predictive value (88 percent and 99 percent, respectively).3

The time-dependent risk to externalization appears to be four to five years’ post-implant.3-5 Hauser and colleagues link 22 deaths to Riata/Riata ST failure from short circuits, but no deaths were linked to conductor externalization.6 A more recent study has shown that postero-anterior and lateral chest X-rays could also be an acceptable mode of imaging for the identification of insulation breaches.7 A separate yet potentially confounding issue is the increased incidence in abrasions against pulse generators linked to Optim-coated St. Jude Medical defibrillator leads, which is beginning to appear in the literature.8 A recent retrospective analysis indicates that the continued use of dual coil leads should be discouraged as they are associated with higher complication rates.9

Conclusions
There is no consensus on how to proceed when a lead is suspected to be defective. Implanted devices ought to be interrogated, but it is not entirely clear whether fluoroscopic screening should be performed. At present, with the recalled Riata lead, the FDA calls for fluoroscopy. However, fluoroscopic evaluation of externalization may not necessarily correlate with lead electrical failure.2-5 Prophylactic replacement should be weighed against the risks of surgery. Further study of the effect of externalization on lead failure and mortality studies is warranted.

Pacemaker Lead failure

Visualizing PPV for Intuitive Understanding and Application

Resus Review

A 1978 study by Casscells showed that physicians were dismal at using PPV test characteristic (positive predictive value, Bayes estimation) for assessing the value of a laboratory test. It was repeated this year with similar disappointing results. Both studies posed a simple question on application of laboratory test results given the test characteristics.

Here is the question both studies used.

“If a test with perfect sensitivity to detect a disease whose prevalence is 1/1000 has a false positive rate of 5%, what is the chance that a person found to have a positive result actually has the disease, assuming you know nothing about the person’s symptoms or signs?”

Only 25% got it right. The others were spectacularly wrong.

Using PPV and Bayes Formula

There are several ways to solve this problem. Shown below is how calculate the answer using PPV and Bayes formula.

PPV and Bayes formula solution for problem

Visualizing PPV

While understanding the math is important, you can develop a more intuitive understanding by visualizing the population (see figure below). If a draw a sample of 1000 patients from the population (all of the dots), only one will have the disease (red dot). Since the test has a 100% sensitivity, it will be a true positive. The remaining 999 patients do not have the disease, but 50 of them will test positive (blue dots), and the rest will test negative (black dots).

Notice that the false positive blue dots far out number the true positives. If this hypothetical example, those patients would be subjected to unnecessary further workup or treatment.

Visualization of sample population

Visualization of a sample population of 1000 patients. Red dots represent true positive patients, blue are false positives, and black are true negatives.

The solution to the posed question then is easy to see. If your patient has a positive test (which 51 out of 1000 would), only 1 actually have the disease. 1/51 is then calculated at 1.96%. PPV calculation done by visualization without any formula memorization.

References

  1. N Engl J Med 1978;299(18):999. Interpretation by physicians of clinical laboratory results.
  2. JAMA Internal Medicine 2014;174(6):991. Medicine’s Uncomfortable Relationship With Math: Calculating Positive Predictive Value.

Is PPV intuitive for you? Share your thoughts below.

Visualizing PPV for Intuitive Understanding and Application

Dinitrophenol Poisoning

Resus Review

Medical knowledge, especially in toxicology, is built on experimentation and the preciously won experience over time treating the ingestions and poisonings of our patients. Ignoring these hard won lessons, and having additional patients repeat the suffering is a most pitiful waste. This has been the case with 2,4-dinitrophenol (DNP), which despite abundant evidence of its danger, continues to tempt because of its promise of weight loss.

Dinitrophenol Uses, Mechanism, and Effects

Dinitrophenol chemical structure

DNP is an industrial chemical widely used in manufacturing. Discovered in 1933, it incidentally was identified as promoting weight loss. As much as 2 lbs/week loss could be seen, which drove its use as a diet aid. DNP uncouples mitochondrial oxidative phosphorylation, interfering with the body’s ability to store energy as ATP. This leads to a dramatic increase in the metabolic rate, and hyperthermia to dissipate the heat. A secondary effect of depletion of ATP caused release of calcium from the sarcoplasmic reticulum and intractable muscle contractions which would generate additional thermal heat.

Unfortunately, its narrow therapeutic window, meant that even while taking recommended doses levels could become “toxic”, and severe side effects were seen including blindness (dinitrophenol cataracts) and death. Federal Food, Drug and Cosmetic Act of 1938 called the chemical “extremely dangerous and not fit for human consumption”. Popularity quickly waned and reported complications from the drug nearly disappeared.

Clinical Presentation and Treatment of Dinitrophenol Toxicity

Presenting symptoms usually include hyperthermia, nausea/vomiting, and diaphoresis. Severe neurological effects such as confusion, agitation, convulsions, and coma are common. The severe hyperthermia can be difficult to control, and patients die of hyperpyrexia and multiorgan failure and refractory shock.

Treatment is almost exclusively aggressive support cares.

  • Fluid resuscitation
  • Cooling for correction of hyperthermia
  • Sedation
  • Airway control

From a physiology mechanism, treatment with dantrolene would seem to offer benefit. Since dantrolene inhibits release of calcium from the sarcoplasmic reticulum, reduction in muscle contractions and heat generation should be possible. The threshold for treatment is set at 39-40°C by the U.K. National Poison Information Service (NPIS) guidelines.

Is DNP readily available?

Because of its reputation for weight loss the lessons of DNP have been forgotten or ignored, and the use of DNP is increasing along with occurrences of its toxic effects.

While DNP is certainly available over the internet, self-reported ingestions should be investigated closely. For example, on Amazon.com there are a large number of diet aids using the term DNP as a marketing ploy, without actually containing any DNP at all. True sources of DNP come from industrial or shadier sources.

DNP products available on Amazon.com

Results searching for dinitrophenol products on Amazon.com.

Most of these diet aids, consist almost entirely very large amounts of caffeine which can generate symptoms similar to DNP.

  • CNS: agitation, confusion, tremor, seizure
  • Cardiovascular: tachycardia, palpitations
  • Gastrointestinal: nausea, vomiting, diarrhea

However, the prominent feature of hyperthermia, muscle contractions, and severe lactic acidosis would not be seen in large caffeine ingestions and could be indicators of true DNP toxicity.

References

  1. Clinical features and treatment in patients with acute 2,4-dinitrophenol poisoning. Lu Y et al. J Zhejiang. University Science Biomed & Biotechnol 2011;12:189-192.
  2. 2,4-Dinitrophenol (DNP): A Weight Loss Agent with Significant Acute Toxicity and Risk of Death. Grundlingh J et al. J Med Toxicol 2011 July 8.
  3. Fatal 2,4-dinitrophenol poisoning…coming to a hospital near you. Siegmueller C, Narasimhaish R. Emerg Med J 2010 May 29.

Have you had a case of dinitrophenol poisoning? Share your experience below.

Dinitrophenol Poisoning