Science AMA Series: I’m Dr. Dean Elterman, a urologic surgeon at the University Health Network in Toronto. My clinic and research focus are on men’s health, urinary health in both men and women, and prostate health. AMA!


Hi Reddit!

I’m Dr. Dean Elterman, a urologic surgeon at the University Health Network in Toronto. My focus on urology and its related diseases has led me to look more closely at how this field fits with overall male health. I’ve published research showing how the urologic community has a leading role to play in helping define the health issues that face men in the 21st century and improving their health outcomes and mortality rates.

There are many factors such as ‘masculine identity’, social determinants and even the Y-chromosome itself that affect men’s health and longevity, and we’ve seen the evidence that up to 80 per cent of men refuse to see a physician until they are convinced by a spouse or partner to do so. The science and medical communities need to find ways to overcome these barriers so men can achieve good health, and one of those ways is through awareness and open discussion which is why I’m excited to host today’s AMA on what you need to know about your prostate health.

Information about prostate health has changed a lot over the years. I’m happy to answer your questions about enlarged prostate, prostate cancer, the traditional and new treatments that exist for both, and when to consider having prostate health conversations with your healthcare practitioner. Note that I’m not able to provide medical advice online, but can point you in the direction of valuable online resources.

I am live now and answering your questions– Ask me anything! AMA!

Thanks very much for your thoughtful questions and for this important discussion. I am now done my AMA session - apologies if I didn't get to answer your question and thank you for participating!

To learn more about my research at the Krembil Research Institute and University of Toronto, [please click here]

( You can read other research I’ve worked on about how men’s health fits with urologic health here.

How do you respond to studies questioning the efficacy of prostate screenings? Is there good scientific evidence that they are beneficial on average?


Hi Millers_Tale - thanks for tuning in. There have been a number of conflicting studies with respect to the efficacy of prostate cancer screening using PSA on a population-basis; meaning should we test every man with PSA. There were two very large studies, one in the U.S. called the PLCO and another in Europe called the ERSPC, that were designed to see whether screening or lack of screening resulted in reducing deaths from prostate cancer.

The American study, was flawed as many men in the non-screening group received PSA tests. That study did not show an advantage to PSA screening. The European study, which had 180,000 men enrolled, is now the largest PSA screening study to date and has followed men for over 13 years. This study demonstrated that PSA screening will lead to early detection and a reduction in prostate cancer deaths. The study showed that screening benefit men under the age of 60 the most.

The take home message I would give when it comes to PSA screening, is that a man should have a conversation with his physician about the risks and benefits of having PSA blood test. I think the harms that have been the focus of so much controversy really surround the over treatment of cancer and not the over diagnosis. Thanks for tuning in today.

Hey doc,

What're your thoughts on the current state of testosterone replacement therapy? Many agree that the current bloodwork range is skewed since it's too large and doesn't take enough variables into account for each patient, such as age (so someone who is 27 and another person who is 77 may have the same levels, but since they're both "in range" they're both normal).

Does the positives outweigh the negatives of TRT? Do you consider it safe overall?


Hi PoppaDR3W -- thanks for these questions, Testosterone Replacement Therapy has definitely been a hot topic lately:

Men’s levels of testosterone decline starting in their 20s - this is a natural phenomenon. We know that there are advantages to having a testosterone level within the “normal range”. Normal laboratory values are based upon historical groups of patients and is what we use as reference range for a variety of blood tests. When talking about testosterone levels and replacement, we typically look at a number of factors most importantly whether the man is symptomatic from having low testosterone and whether his total testosterone blood sample is low. TRT should only be considered in men who have at least two morning testosterone levels measured to be low and are symptomatic i.e. fatigue, depression, low libido, erectile dysfunction, loss of muscle mass, weight gain to name a few. TRT should be taken under the supervision of a physician.

Looking at the evidence as a whole, the positives of having a normal level of testosterone with the use of TRT outweigh the negatives. I am not an advocate, however, of taking TRT recreationally or in the cases of men without documented low testosterone. Thanks for your question.

Hello Dr. Elterman, thanks for doing this AMA! I am a 23 year old man who has never been to an urologist out of fear of circumcision. My foreskin is a bit too tight and I am scared that the solution to this might be circumcision for most doctors, even when I read that there are cremes available that might help this problem. What can you tell me that might alleviate these fears and get me to go to a doctor?


Hi lordureq, thanks for tuning in. The first thing I would say is that if you have any health concern, you should really seek medical advice. Fear of seeing the doctor will only lead to any potential problem being overlooked. I can’t speak to your case specifically but the medical condition associated with a tight foreskin is called Phimosis. We would only treat this condition if it results in infections beneath the foreskin or in the urinary tract, or if it interferes with sexual function such as causing pain with erections. Some topical creams that contain a steroid can loosen the tight ring of skin though the success rate for this is relatively low. If it’s really interfering with your life, some sort of surgical intervention may be required. There are some alternatives to a circumcision such as preputioplasty which is a limited incision to open up the tight area just enough without removing the entire foreskin. Don’t let your fear prevent you from seeing a physician, that’s the best way to find out about alternatives that may exist. Thanks for your question!

As a early 30's man considering vasectomy as a viable form of birth control, is there anything I should be concerned about health wise? Has there been any link to prostate cancer or lowered testosterone?

Thanks for your time!


Hi BarefootDogTrainer,

Thanks for tuning in today. Vasectomy is one of the most commonly performed surgeries in North America. It is a highly effective form of birth control/contraception. Even though there are surgeries to reverse a vasectomy, I would counsel my patients that they should consider vasectomy as permanent contraception. One concern following vasectomy may be chronic testicular pain though this a rare occurrence. While there have been some studies that looked at associations between vasectomy and other diseases such as prostate cancer, none have demonstrated a causal link. Thanks for your question!

Hi Dr. Elterman, thank you for this AMA! My question to you is, how helpful are PSA levels towards diagnosing prostate cancer and BPH? What other diagnostic options would you say are up and coming in the field of urology that would have better PPV than PSA levels? Thanks!


Hi Infamouscurry,

Great question! Prior to the era of PSA testing, most men would present with advanced forms of prostate cancer and rates of death directly as a result of prostate cancer were much higher than they are today. While PSA is not a perfect test for the diagnosis of prostate cancer, it has allowed us to detect cancers at earlier stages and prevent many of these deaths.

We use the change in PSA over time as an indicator that cancer may be present within the prostate, there’s been a lot of controversy around PSA testing based upon a number of recent large studies. The general consensus amongst the urologic community is that PSA testing remains a valuable tool to identify men at risk for prostate cancer. My belief is that if PSA is used wisely, and we don’t over treat cancers that will cause no harm to men, such as Gleason 6 prostate cancer, then we should still use it until a better test becomes available. In terms of new and up and coming tests, we are currently offering the PCA 3 urine test as well as the 4K score, a type of blood test.

In terms of BPH, PSA is a good substitute for prostate size as well as response to treatment. I hope that helped to answer your question.

Hi Dr. Elterman!

A coworker's husband (prostate cancer survivor) just had his prostate removed. What can they expect in terms of his sexual function during and after recovery?


Hi Blaklwyr13,

Thanks for your question. Though I can’t speak to your co-worker’s husband’s specific case, in general, after prostate removal the average rate of erectile dysfunction is approximately 62%. The two main consequences of prostate removal (radical prostatectomy)are urinary incontinence and erectile dysfunction.

However, there are many treatments available for erectile dysfunction. I actually gave a webinar on this very topic. There are a wide variety of different treatments including: pills, injections, vacuum devices (penis pumps), and surgical implants. Here is the link to my webinar that discusses these options in more detail: However, this is another discussion that a patient should have with his physician in order to choose the best option for his situation. Thanks again for turning in.

Dr Dean Elterman, Thank you for doing this AMA. What can 20-30 year old males do to avoid, mitigate, or completely eradicate any of the health problems that you study? In particular, are there any food / drinks that should be avoided or consumed more frequently? Any specific exercises that can weaken or strengthen any of the organs, muscles, or tissues related to the parts of the body that you study?


Hi zziTizz, thanks for tuning in today. There are many things you can do proactively to ensure that you stay healthy as you age. Here is an article I wrote about that very topic:

In general, healthy eating, regular exercise, and stress management in your 20s and 30s will prevent obesity, cardiovascular disease, and burnout in later life. There is a direct relationship between the processes that lead to metabolic syndrome and diabetes and erectile dysfunction. It’s really important to look at men’s health holistically and see the connections between all of our body systems. Thank you again for your question!

Hello. To your knowledge, what does the current literature say about the relationship between varicoceles and low testosterone or depression-like symptoms in men?


Hello arise_chckn, thanks very much for your question. Varicoceles are essentially varicose veins of the testicles. When you have varicoceles, this may raise the temperature of the testes as well as cause other abnormalities resulting in testicular dysfunction. Untreated varicoceles can lead to testicle shrinkage and in turn less testosterone is produced by the testicles.

The classic appearance of a clinically significant varicocele is a “bag of worms” if your scrotum has this appearance or you’re losing testicular volume (size) then you should have this checked by a urologic professional.

Low levels of testosterone can result in depression-like symptoms, which is the consensus across the field of urology. This can include low energy, difficulty concentrating, fatigue, lethargy. Varicoceles have been associated with infertility but if surgically corrected, fertility and testosterone levels may return to normal. Thank you again for tuning in.

Given the statistic you provided regarding 80% of men refusing to seek medical help until convinced by a partner/spouse, I'm wondering how that figure has changed over the years. Or how it varies generationally - i.e., are baby boomers better/worse? are millenials better/worse?


Hi Izawwlgood - thanks for the question. Research has supported the notion that the preservation of masculinity is often what prevents men from admitting vulnerability and seeking help. During the 20th century, we spent a lot of time improving the health of women and children who are typically seen as disadvantaged groups. In the meantime, men were out in the workforce and there was little emphasis placed upon their health needs. Many of my older patients come from a generation where they would not complain of ailments until they became disabling. I have seen a generational shift in my younger patients who are proactive about their health and savvy about looking up their symptoms (for better or worse). Great organizations like Movember have really engaged young people to have conversations about men’s health and to encourage friends and family members to get checked out for prostate and testicular cancer as well as mental health concerns. I would expect that 80% figure to decrease as time goes on. Thanks again for tuning in.

I have recently been diagnosed with prostate cancer. I have sought out what would be the best course of action for my treatment. There is very little online information for guidance. For example, If you are this age, and at this stage, this has been shown to be the best course of action. I feel a database would be helpful in making a logical decision for a course of action. Is there a source(s) where such demographics could be found for the public?


Hi mikeoc1969 - I'm sorry to hear about your diagnosis and thanks for sending in your question. There are some good existing “decision aids” that currently exist. Here is the link to one that I helped develop and that launched recently: It has been supported through a grant from the Movember Foundation and Prostate Cancer Canada. I hope this will help answer some questions you might have. Thanks again for tuning in and all the best.

As a youngish man experiencing urinary issues it is very difficult to get doctors to take the issues seriously because I am not in the age group of people who normally suffer for these things.

In your experience, regarding urinary issues and young men, is this normal?

Also, how do young men with these issues go about getting help without being constantly dismissed?



Hi NonOpinionated,

Thanks for your question. In general, urinary issues become more common as men age. That being said, young men can certainly be afflicted by a variety of urinary concerns. Young people can develop an overactive bladder whose symptoms include: urinary urgency, frequency, and waking up at night with urgency to urinate. It’s important to rule out a urinary tract infection or prostatitis which can also result in bothersome urinary symptoms. Other causes may include pelvic floor dysfunction, or an anatomic obstruction such as scar tissue. I think it’s important to find a healthcare professional who will take your concerns seriously and do a thorough evaluation of all these potential causes. Thank you for your question.

I'm a 33 year old healthy female and last January I started experiencing what I thought was a UTI- but it was different from any UTI that I had ever had before in that the main symptom was greatly exaggerated urgency which, while somewhat intrusive during my day to day, was mostly intruding in my life right before bed in that I would feel like I had a full bladder and would get up to go urinate, maybe 10 times (with only a few drops coming out) until I would get tired enough to fall asleep on what felt like a full bladder. I have been to my regular doctor, my gynecologist, and a urologist and got negative UTI tests back at all three. My regular doctor knows this has continued and has said it's likely nothing serious and nothing can really be done about it except for me to try to train my bladder to get used to this new normal. Do you have any advice as to what I can do to get used to this so I can fall asleep at night?


Hi SleepingAnima - Thanks for this question. Without speaking to your specific condition, many young women experience of a urinary tract infection but end up having negative urine cultures. It is considered normal for women to have up to two urinary infections per year. I was interviewed about this topic recently which you can read here:

Some women may have a urinary tract infection which clears but the symptoms persist as a result of the development of pelvic floor dysfunction. The muscles that surround tour bladder in the pelvis become hypertonic (too tight) and they result in the same symptoms as a UTI such as urinary frequency and urgency. The single best treatment that a person can seek if they have these symptoms in the absence of an infection is pelvic floor physiotherapy performed by an accredited physiotherapist. The last thing I would say is that doing Kegel exercises will only make this condition worse as you are tightening an already over tight pelvis. Many thanks for tuning in.

I am 61 and have BPH. Is there anything that I can do to reduce how often I have to pee at night? I haven't slept for eight hours straight in at least three or four years. I'm up every hour and a half. I'm on high blood pressure medicine with a diuretic and a baby aspirin a day, Zantac for my reflux. Is this my fate for life? edit: punctuation.


Hi Leatherneck55, thanks for tuning in. I will confine my answer to the general topic of nighttime peeing without getting into the specifics of your case - you should speak to your healthcare provider about your case. Nighttime urinating also called nocturia, can be a symptom of several possible underlying conditions. Men who have an enlarged prostate may not empty their bladder completely and as a result may be up throughout the night as the bladder fills up. Another possibility is that men can develop overactive bladders, which can result in nighttime urgency forcing them to wake up from their sleep with the strong urge to urinate. Another interesting condition is called nocturnal polyuria, which is the overproduction of urine at night. There are several causes of this including sleep apnea (respiratory interruptions while sleeping), congestive heart failure, diabetes, or prescription drug-related (side effects of any medications). Sometimes, a solution may be as simple as taking your diuretic in the morning, and elevating your legs in the evening to reabsorb the fluid in swollen ankles, and possibly use a CPAP (breathing machine) if you have sleep apnea. Thanks for the question.

Hey Dr. Im 33. When I was 29 I was disgnosed with prostatitis. It took me 5 MDs and a specialist (and thousands of dollars) to diagnose. Is this some elusive thing? Why would it be so hard to figure out... Thanks for the AMA.


Hi FortCollinsEnt, thanks for your question.

Prostatitis means inflammation of the prostate - think appendicitis, meningitis, etc. What can be elusive though is that there are different types of prostatitis such as bacterial or non-bacterial. In the absence of finding a bacteria, it may difficult to target with a specific drug. There are other conditions which can look like prostatitis such as an overactive bladder or bladder pain syndrome/chronic pelvic pain syndrome. Also, there is no one specific treatment for prostatitis. It often requires a combination of antibiotics, anti-inflammatories, pelvic floor physiotherapy and psychological support. Thanks for your question.

I'm 27 and sometimes when I hear people older than me pee in the next urinal, it comes out in increments. Why is this and does this happen to everyone? How do I prevent it? Is it from possible prostate cancer, masturbation, or sex?


Hi o-rka: great question, thanks for sending it in. One of the symptoms of an enlarged prostate is the obstruction of urine flow. Prostate enlargement is much more common in older men, affecting 50% of 50 year old men and up to 80% of 80 year old men. Men may have a difficult time initiating their stream (hesitancy) and the flow may come out in stops and starts (intermittency). Other symptoms of prostate enlargement may include a slow flow, straining to empty, and post-void dribbling.

Staying healthy and paying attention to changes to your body and peeing are the best strategies you can employ as you get older. Thanks for tuning in!

Hi Dr. Elterman! I really appreciate you doing this! I'm currently in class right now, and thought I would ask 2 questions:

How do you tell the difference between distal straight/convoluted tubules in the kidneys? (I thought I was being funny but... now I can't tell)

Why is it that so many men develop prostate cancer and what types of diets/lifestyle changes can one undertake to limit the chances of that happening?


Hi Tamatone - Thanks for your question. Prostate cancer is the most common cancer in men (other than skin cancer). We’re still finding out all of the causes of prostate cancer but certainly family history, and possibly inflammation earlier in life are factors in the development of the genetic mutations that cause prostate cancer. An active lifestyle and healthy eating are important in preventing many types of cancer, as is minimizing red meats and other carcinogens. Many thanks again for tuning in.

How much of an affect does getting a vasectomy have on acquiring prostate cancer?


Rolliebijou: Thanks for your question -- Please see my answer to BarefootDogTrainer's question in this AMA for more information. Thanks for tuning in!

My dad was diagnosed with stage four colon cancer almost exactly one year ago. He's always found a way to make people laugh through hard times (He jokes that if he lives too long he might actually have to pay some of his credit card bills hahaha). I know medical advances take more time than he has, so please don't take this as a "how are you folks going to save my dad's life?" Sort of question...

What, in your opinion, is the most exciting recent advance in prostate cancer research? As a follow up question, where do you think this may lead us in the next twenty years?

Edit: I took out a bit about my dad's PSA levels because they sound absurdly high.


Hi JayShocker - thanks for your question and I’m sorry to hear about your dad’s diagnosis. There is a lot of encouraging work going on in prostate cancer research. We are entering an era of personalized medicine thanks to advances in genome-sequencing technologies. I think over time we will be able to use genetic information to identify the types of prostate cancers which will actually cause harm to men and those which will remain harmless (indolent). Stay tuned! Thanks again for your question.

Are kidney stones hereditary? I get them, my mom got them, my daughter gets them. It seems to happen earlier with each generation - mom at 40 something, myself at 18, daughter at 9.

I also have a lot of confusion on how to prevent them. My daughter and I both get calcium oxalate - so that means we should avoid leafy greens, artificial colors right? Sometimes it seems unavoidable to consume those.


Hi toadallyfroggincool - thanks for tuning in. I can’t give you specific medical advice. But, in general, there are many types of kidney stones and some are hereditary. Mutations of certain genes may result in abnormal metabolism of certain amino acids and other substances. People who have stones that run in their family may have one of these underlying metabolic disorders. If that’s the case, they should probably see a kidney stone specialist (nephrologist or urologist) and get some advice on what foods should be avoided and other dietary or medical modifications that need to be instituted. Many thanks again for your question.

Does regular ejaculation prevent prostate cancer?


Hi Year_Of_The_Horse: thanks for tuning in today. Although there is a bit of research in this area, to date there is no evidence that frequent ejaculation may have a protective role against prostate cancer.

Hi Dr. Elterman.

Recently I was diagnosed with a varicocele, and naturally I've been looking up the solutions for treating them that my doctor will use once my appointment comes up.

Can you help me understand these procedures? I've read one is a low recurrence rate but this is basically the regular surgical option.. I have also read of laproscopic or radiologic methods, but they evidently have a higher rate of complications and potentially ineffective.

Can you comment on which of these has the highest rate of efficacy along with the lowest rate of recurrence? I've read horror stories of embolization with little wires and having extreme pains lasting after the procedures, and I'm REALLY not too excited about getting my boys worked on (even though it's super important but.. knives!! doctors!! :( )

Thank you!


Hi AltoRhombus - thanks for tuning in to my AMA. There are a number of treatment options available to men who have varicoceles. A microsurgical approach where a very small incision is made in the groin is a very effective and minimally invasive option for men. The alternatives, which include laparoscopic ligation and interventional radiology embolization are also reasonable alternatives. Each treatment will always come with its own specific set of risks and benefits. Seeking the advice of an experienced urologic surgeon will help you make the right decision. Thanks again.

Good morning sir, thank you for taking your time out to do this!

I am 39, seven months away from 40. Haven had any physical checkups in at least seven years and have not seen a doctor for anything except a slight knee injury in two years.

The only thing I feel abnormal with health wise is that I am 250 pounds but only 5'9, I have trouble sleeping at night and rarely feel rested in the morning, and a certain thing happens quite prematurely more often than not.

Is there anything ultra-pressing that I should be concerned about? When I do go see a doctor, what questions should I be asking?

Thank you in advance!


Hi AnthoAmick -- thanks for tuning in. I can’t stress enough the importance of seeing a doctor on a regular basis. I think turning 40 is a great opportunity to do a full medical assessment/check up. Addressing issues such as excess weight and difficulty sleeping may significantly improve your life, and pick up on more serious conditions. Here is a great resource in terms of what questions you should ask your doctor: Thanks again.

Can enlarged prostate lead to ED?

Is there a relationship between diet and enlarged prostate? What diet/food alleviates the symptoms associated with enlarged prostate?


Hi ed_and_food: Great questions. There is a common link between ED and enlarged prostate and that may be metabolic syndrome and endothelial dysfunction. Men who are overweight are more likely to develop the precursor to diabetes which is called metabolic syndrome, one of the consequences to this is problems with blood vessels and circulation. The arteries going to the penis are some of the smallest in our body and are most likely to be affected (blocked) resulting in erectile dysfunction. Larger waist circumference and body mass index (BMI), have also been linked to having a larger prostate. Therefore, addressing obesity and its negative metabolic effects may improve sexual function and urinary symptoms. You can learn more in this article I wrote for the Globe and Mail: Thanks for tuning in!

What are your thoughts on the longer-term use of dutastertide for hair growth?


Hi Skeptickler - Thanks for your question. Dutasteride is from a class of drugs called 5-alpha reductase inhibitors. They block the conversion of testosterone to dihydrotestosterone. When taken at a lower dose of 1 mg, it is used to promote hair growth and when taken at a higher dose of 5 mg it helps promote prostate gland shrinkage. The possible side effects of taking this medication include low libido, erectile dysfunction, and breast tenderness or growth. One entity which has been described is something called post-finasteride syndrome, which is the persistence of these symptoms after the discontinuation of drugs like dutasteride or finasteride, a similar drug. Many men take dutasteride to promote hair growth for many years and don’t experience any of these side effects. If you have concerns about the long term use of this or any drug, you should speak to a healthcare practitioner. Thanks again for tuning in.

Hi Dr. Elterman, thanks for the AMA!

You state that you find

up to 80 per cent of men refuse to see a physician until they are convinced by a spouse or partner to do so.

So, my question is - how do you change that behaviour? What interventions or culture change might make men more likely to see doctor when necessary?


Hi superhelical, thanks for this question that really gets to the heart of men’s health. A cultural change amongst men whereby we redefine masculinity as incorporating taking care of your health and yourself would be a good start. Taking time out of our busy work and personal lives to address health concerns early as opposed to waiting for a crisis will result in improved health for men. I think this may be a generational change that is taking place whereby younger men and their partners are more engaged in staying active and healthy, which includes regular health checkups. Many thanks for tuning in.

In Urology, what are the early warning signs to indicate the need for a professional evaluation (if any)? I'm aware of checking yourself which I do regularly, but what other non-obvious (blood in urine, painful urination) warning signs are there that I can be aware of?


Hi guitbit, thanks for your question. The main self-examination relating to urology is the testicular self examination:

This is an important test for young men. If you feel any change like a lump, bump or hard nodule like a pea, you should have this checked out immediately. In general, any changes to your urination, specifically blood, should also be brought to the attention of a medical professional as it could be the sign of a serious underlying condition such as bladder cancer. Thank you for tuning in.

Have suffered the embarrassment of extreme PE all my life. Are there any new treatments, uh, coming soon?


Hi thr0w_aweigh - The concern over premature ejaculation (PE) is one that is experienced by many men. One of the misconceptions is in the definition of PE. The average of amount of time that it takes for men to ejaculate during intercourse is just over 6 minutes, the definition of PE would be someone who ejaculates in less than 2 minutes. I see many men who have concerns about PE but in fact they’re expectation of stamina is overestimated. There are a number of treatments available ranging from sex therapy which includes “stop-start” technique. Successful medical treatments include the use of antidepressants namely selective serotonin reuptake inhibitors (SSRIs). Thanks for tuning in.

Hey thank you Dr. For doing this AMA, quick question. For adults in college. Use to hard drink in high school because of young age, but stopped for a while. Now in college hard drinking again, for urinary health how far enough do you have to go until you know it is bad enough for the liver. I mean some have got stomach pain but when gone to the doctor it's everything is alright. Is alcohol really affect urinary health or does it need years of damage? Thank you for your help.


Hi LuminosityVibe -- As a urologist I’m not going to specifically comment on binge drinking more than to say that it is far more harmful than drinking in moderation, and please drink responsibly! Thank you for tuning in.

Hello good sir, when do you say a guy should check his prostate? Are there any indicators that could point out to possible prostate issues?



Hello Bandukii - thanks for tuning in. Men should have a discussion with their doctor about prostate health at age 50 to determine what the best approach is to your prostate health. I recommend a baseline PSA at age 50 especially if you have a family history of prostate cancer. Many thanks again for your questions.

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