Arjuna

Terminalia arjuna, frequently referred to as arjuna, belongs to the family of Combretaceae. Its bark preparation is being utilized in the Indian subcontinent for anginal pain, hypertension, heart disease, and dyslipidemia, based upon the observations of ancient physicians for centuries.It is an ayurvedic remedy that has been mentioned since vedic period in many ancient Indian medicinal texts including Charaka Samhita, Sushruta Samhita, and Astang Hridayam. [1]

History

According to the Mahabharata – among the most reputable books of Indian mythology – Arjuna was among 5 brothers and a central character in this ancient Indian legendary. Son of the god Indra and renowned for his talent in archery, he was known for his steadfastness and single mindedness in pursuing his objectives. His commitment to Lord Krishna made him the magnificent knowledge of the Bhagavad-Gita and the character of Arjuna signifies purity, stability, commitment and valour. It is stated that the hero of this legendary was called after the Terminalia Arjuna tree because of its protective impacts. The Arjuna herb was understood for its function in protecting vigor and was nicknamed “Guardian of the Heart”, displaying similar characteristics to the hero of the Indian legend. In Sanskrit the word Arjuna means “shining”, alluding to the silvery sparkling quality of the external bark of the tree. Once a year this bark peels away to expose the inner red recovery bark, making it available for harvest without damage to the tree. [2]

Description

Arjuna grows to about 20– 25 metres high; generally has a strengthened trunk, and forms a wide canopy at the crown, from which branches drop downwards. It has oval, cone-shaped leaves which are green on the top and brown listed below; smooth, grey bark; it has pale yellow flowers which appear between March and June; its glabrous, 2.5 to 5 cm fibrous woody fruit, divided into five wings, appears between September and November. The tree does not experience any major illness or pests, but it is prone to Phyllactinia terminale and rot due to polystictus affinis.

Distribution and habitat

The arjuna is seen across the Indian Subcontinent, and generally discovered growing on river banks or near dry river beds in Uttar Pradesh, Bihar, Maharashtra, Madhya Pradesh, West Bengal, Odisha and south and central India, together with Sri Lanka and Bangladesh. It has actually also been planted in Malaysia, Indonesia and Kenya. [3]

Classification

• Kingdom: Plantae
• Division: Magnoliophyta
• Class: Magnoliopsida
• Order: Myrtales
• Family: Combretaceae
• Genus: Terminalia
• Types: T. arjuna
• Zoological name: Terminalia arjuna

Other names: Arjuna, Koha, Kahu, Arjan, White Marudah, White Murdh, Arjuna Myrobalan, Orjun, Yerra maddi, Sadada, Sadaru and much more. [4]

Characteristics of the Arjuna Tree

Arjuna, likewise called arjun, is a stunning, deciduous tree that can reach heights up to 100 feet and has actually been valued for its wood and therapeutic homes for generations. It grows throughout the damp, marshy, sub-Himalayan regions of India and Sri Lanka, producing clusters of little white or yellow flowers amid its cone-shaped leaves. The most sought-after part of the tree is its red inner bark, which is respected as a tonic for the heart and is considered comparable to hawthorn in European herbalism. The thick, white-to-pinkish-gray external bark molts naturally once a year and is harvested when the trees are mature. Offering the tree time to recuperate and regrow its bark is a key part to sustainable harvesting. Centuries ago, the arjuna tree was provided a name befitting its standard role of safeguarding the heart, much like its mythological name brought fortitude, strength, and protection to his family in battle.The term “arjuna” implies “intense,” “white,” or “shining” in Sanskrit, much like the light-reflective bark of the arjuna tree.

Phytochemistry

The significant constituents of T. arjuna in stem bark, root bark, fruits, leaves and seeds are well identified. The preliminary phytochemical analysis of existing compounds in T. arjuna was performed according to various basic procedures. As bark was considered to be the most important constituent from the medical viewpoint, initially reported that the bark had 34% ash content consisting totally of pure calcium carbonate. Aqueous extract of T. arjuna is reported to have 23% calcium salts and 16% tannins. Organic extracts of T. arjuna bark were also prepared utilizing the consecutive methods with a number of organic solvents such as hexane, benzene, chloroform, acetone, dichloromethane, ethyl acetate, butanol, ethanol, methanol and ether, etc, to extract numerous phytochemical constituents. The chemical structures of available compounds were validated by numerous innovative techniques like HPLC, UPLC, LC-ESI-MS/MS analysis.26, 27, 55, 56 Polyphenols, flavonoids, tannins, triterpenoids, saponins, sterols and minerals are the major constituents of T. arjuna. Such amino acids like tryptophan, tyrosine, histidine and cysteine are likewise the main ingredients in T. arjuna. [5]

Nutrient

Five bark powder samples of Arjuna (Terminalia arjuna) having different origins including two industrial brand names were examined for 8 minor (Al, Na, K, Mg, Ca, P, Cl, Fe) and 19 trace (As, Ba, Br, Co, Cr, Cs, Cu, Eu, Hg, La, Mn, Rb, Sb, Sc, Sm, Sr, Th, V, Zn) aspects by INAA. Also concentrations of Ni, Cd and Pb were determined by AAS and of Sn by ICP-MS. Arjuna bark powder is enhanced in Ca, Mg, K Cl and Fe with considerable amounts of Mn and Numerous toxic components such as As, Hg and Pb were likewise found. [6]

Microscopy

Transverse section of fresh bark shows cork composed of uniformly arranged numerous layers of little, tangentially extended cells. Below cork is a region of cortex, composed of thin-walled, basically brick-shaped parenchymatous cells consisting of cluster crystals of calcium oxalate. A few groups of sclerenchymatous pericyclic fibers are spread in the cortex. Secondary phloem includes phloem parenchyma made up of thin-walled, polygonal cells with wavy walls including cluster crystals of calcium oxalate and pigmented cells. Phloem fibres, made up of sclerenchymatous cells, happen in groups and are scattered in the form of spots in parenchyma. Narrow and nearly straight medullary rays are likewise present. [7]

Prospective advantages

There’s minimal research on arjunarishta, and the majority of it was performed in animals. Therefore, no definitive conclusions can be made about its efficiency in human beings.

High in antioxidants

Antioxidants are substances that neutralize highly unsteady molecules called free radicals. Free extreme damage is connected to chronic conditions like heart problem, type 2 diabetes, and cancer. Lots of components in arjunarishta, such as T. arjuna, V. vinifera, and W. fruticosa, include substances that work as antioxidants, including flavonoids, triterpenoids, glycosides, and phenolic acids.In test-tube and animal research studies, T. arjuna, V. vinifera, and W. fruticosa anti-oxidants have been shown to reduce the development and spread of cancers in the stomach, liver.However, it’s uncertain whether taking arjunarishta would produce similar outcomes, as these research studies were carried out utilizing concentrated extracts. It’s likewise unclear whether these benefits would apply to human beings.

May help blood sugar control

Animal research study suggests that arjunarishta and its components may decrease blood sugar level levels.In a mouse study, researchers discovered that both arjunarishta and T. arjuna extract reduced fasting blood sugar level levels considerably more than a control.Similarly, a research study in rats with diabetes found that treatment with a T. arjuna extract for 15 days significantly lowered and stabilized fasting blood sugar levels.Additional studies in mice with diabetes have actually also discovered the mixture’s components to considerably reduce fasting blood sugar levels.However, arjunarishta includes jaggery– an unrefined sugar item. As such, while most of the ingredients may aid blood glucose control in animal studies, arjunarishta as a whole may disagree for people with diabetes.Human research studies on arjunarishta’s results on blood sugar management are needed before suggesting it for this purpose.

Other possible benefits

Arjunarishta and its active ingredients have been connected with other possible benefits, including:.

May minimize cancer threat. Animal and test-tube research studies suggest that specific components in arjunarishta might have anticancer properties. Still, human research studies are needed in this area.May have anti-asthmatic properties. Animal research recommends that a few of the blend’s ingredients may have anti-asthmatic residential or commercial properties and help in reducing lung inflammation. Again, human studies are needed.May help aerobic workout efficiency. A study in 30 healthy young people discovered that T. arjuna, a key active ingredient in arjunarishta, improved aerobic workout endurance. [8]

Advantages of Arjun Fruit

Removes foul breath

Bad breath is one of the most common way of life issues that accompany lots of people. You would not wish to go to your work place having foul breath. Eating arjun fruit can really improve your mouth odor and can have benefits associated with oral health. This fruit has compounds that have recovery residential or commercial properties that can even aid your gum issues and bleeding from the teeth. You can actually have arjun fruit as soon as every early morning to begin your day with a fresh mouth.

Makes Bones Stronger

If you are suffering from any kind of bone issues, particularly that weakens our bones, then it can be truly effective for you to consume arjun fruit. In the aging, individuals may feel this bone concerns growing over time. Bones of older adults tend to become weaker and that is when you can actually take complete benefits of arjun fruit. You can consume it raw of make a juice out of it. It might even assist you with bone conditions like osteoporosis and arthritis. It might not have the ability to treat it but can lower its signs.

Decreases Teeth and Gum Issues

Oral health plays an extremely vital role in identifying the lifestyle, confidence and some other aspects. Eating arjun fruit can actually help you lower your gum issues and improve teeth health. Here are some typical oral issues that could be dealt with by eating arjun fruit in your diet plan-.

• Bleeding from the teeth
• Minimizes cavities
• Toothache
• Discomfort in gums
• Bleeding gums

You can have this fruit in the form of juice, or raw. You can also consume arjun fruit powder and put it in the form of a paste on the area where you are facing gum or teeth issues. However, it is much better to consult a physician first and take arjun fruit more as a treatment than a treatment.

4. Improves Heart Rate Rhythms

It has actually been observed that eating arjun fruit frequently in your diet plan can reduce the threat of heart rhythm condition. This fruit can help to maintain normal heart rate rhythm that could reduce the danger of cardiovascular disease. You can also have arjun bark powder and blend it in a glass of water with some honey to purify your blood. Arjun fruit thus could be beneficial to improve heart health as well. [9]

Extract preparation

The sun dried bark of T. arjuna was given the laboratory and powdered and extracted in water (1:8, after going through 80 mesh size) by boiling (4 h). The extracts were consequently infiltrated muslin fabric and the filtrate was spray dried. For preparation of water service of T. arjuna extracts, dried powder (500 mg), was dissolved in distilled water and then centrifuged (500g, 15 min). The supernatants were moved to micro-centrifuge tubes and saved (at − 20 ° C). The quantity of overall soluble solids in supernatant was measured using gravimetric analysis which functioned as the basis to formulate T. arjuna concentrations. [10]

Approach of Preparation Of Arjunarishta

The main ingredient arjuna is cleaned and sun-dried. It is then powdered and sieved to eliminate pollutants and strong particles.Separately, the fragrant herbs i.e. madhuka, dhataki and draksha are cleaned up, dried, powdered, sieved and kept aside. The powdered arjuna bark is then immersed in a particular quantity of water and allowed to soak overnight. In the morning, the decoction is then boiled and minimized to 1/4 quantity and passed through a muslin cloth to get rid of pollutants. Include jaggery to the clear decoction, stir it properly and filter to eliminate strong particles. Now, put the preparation in a wide-mouthed vessel, add the powdered aromatic herbs to the filtrate and seal the opening of the container.Keep it aside in the fermentation space and permit it to ferment. Keep a check on the fermentation procedure. Once the fermentation is done, filter the fermented liquid through a muslin cloth to remove solid particles and pollutants. The concoction is then poured in air-tight containers, stored in a cool, dry location and kept for maturation. [11]

What can I use it for?

Arjuna bark affects an increase in levels of superoxide dismutase, catalase and glutathione levels. This action provides defense against oxidative tension, with a specific affinity for heart tissue. Arjuna also displays a positive inotropic action upon heart muscle, stabilizing any irregular contractions and promoting a healthy high blood pressure. Arjuna mediates the inhibition of cholesterol biosynthesis within the liver, enhancing cholesterol metabolism and likewise encouraging general hepatic cellular regrowth. Arjuna has shown anti-bacterial, anti-viral and anti-mutagenic activity versus specific strains such as salmonella, E.coli and HIV. In addition, it has also revealed the capability to recover harmed and wounded skin cells, and avoid the growth of tumours.

Into the heart of arjuna

Arjuna is first and primary a cardio tonic. Arjuna is particularly shown for all heart based conditions, reinforcing, nourishing and fixing heart and capillary tissue. It will influence a decrease in any inflammation and congestion that may be impairing heart function however likewise support any emotional tension and anxiety affecting the organ.The regenerative result that this herb has on the liver, likewise makes it exceptionally rejuvenative to the liver as an organ, enhancing general efficiency and metabolism, with the added ability of enhancing cholesterol metabolic process. Arjuna recovery process with a specific focus upon broken skin and bones and damage brought on by chronic viral and bacterial infection. Arjuna is specifically suggested in angina, heart disease, cardiac arrhythmia, and hypertension. All have revealed indications of improving in human clinical trials. It has actually also been shown to lower human overall cholesterol and triglyceride levels. It lowers inflammation and congestion that can harm the heart. It can be used to treat emotional disturbance and ‘broken heart’. It strengthens the muscles of the heart in addition to toning the capillaries and improving versatility which helps to prevent high blood pressure. It helps to balance the movement of vyana vayu in the heart and manage flow. Arjuna’s affinity for the chest directs it to the lungs and to reduce efficient coughs with generous mucous in bronchitis and asthma. It can likewise treat haemoptysis influenced by increased heat and inflammation. Arjuna enhances liver function and inflammation, making it extremely suggested in cirrrosis. Arjuna is useful as an alterative for clearing the skin of inflammation common in acne, acne rosacea, pruritus and urticarial.The injury healing ability of arjuna is demonstrated in post-trauma healing of scars, post-operative healing and repairing fractures. It can also be used internally and externally for healing diabetic ulcers.The astringency of arjuna prevents premature ejaculation and uterine bleeding. [12]

How to Take Arjuna

If arjuna’s heart-nourishing powers and myriad of other benefits are calling your name, there are several ways to include this herb into your routine. To determine the manner in which is best way for you, just tune into any specific objectives and trust where your heart is called. And obviously, if you are dealing with a more intricate health condition, we advise dealing with an Ayurvedic professional for specific and individualized guidance. By itself. Arjuna can be utilized on its own for those who prefer working with a single herb. The most conventional approach for taking arjuna is the powder; try drinking it in warm water as a tea. Or try the liquid extract for a quickly, practical option.In a supplement. Arjuna is consisted of in a lot of Banyan’s supplements, consisting of Heart Formula, Tension Ease, Women’s Natural Transition, Healthy Bones, and Sweet Ease. Topically. Arjuna is a best active ingredient for our soothing and soothing herbal oils and balms. It can be discovered in Mahanarayan Oil, Daily Massage Oil, and Breast Care Balm.

Is Arjuna Safe?

Arjuna is typically thought about safe in most circumstances, making it an all set ally for lots of. That said, it’s constantly essential to approach using herbs with care. [13]

Dose

What is the advised dosage of arjuna?

Based on scientific research done on the arjuna plant so far, the following dosages have been advised.

For chest pain: 500mg of the powdered bark of the arjuna plant is advised to be taken three times per day, in addition to the standard treatment for angina for about three months.

For heart failure: 500 mg of powdered arjuna bark can be taken 3 times daily along with the traditional treatment for cardiac arrest for about 2 weeks. [14]

Instructions

1. Arjuna bark being the main ingredient is to start with washed and left for drying in the sun.
2. It is then processed to get the end product in a powdered type. Do keep in mind to sieve the powder once to eliminate the impurities or any strong particles.
3. The other herbs (madhuka, dhataki and draksha) which are used shall also be cleaned completely and sun dried.
4. These herbs are likewise processed to form powder. Keep all the herbs independently and sieve them once to clear the possibilities of strong impure particles.
5. The powdered arjuna bark is then left in water for the soaking procedure for a minimum of 24 hr.
6. The soaked product is then boiled till the amount is lowered to less than half. To get rid of the additional possibilities of pollutants, pass it through muslin fabric.
7. Now add jaggery or gud to the decoction and stir it correctly.
8. Include all the herbs and seal the container tightly.
9. Enable the preparation to ferment properly.
10. When the fermentation is done, filter it once again utilizing muslin cloth to further cleanse.
11. It is ready to use and can be kept in airtight containers. [15]

Arjuna bark for skin

The bark of Arjuna is used to treat numerous skin associated issues. It has antioxidant, anti-inflammatory and antimicrobial homes that assist in getting rid of skin issues.

In Ayurveda, the Arjuna tree has been referred to as a bonanza of medical properties. Arjuna tree, fruits, leaves and roots are utilized in Ayurveda for the treatment of numerous diseases. Let us inform you that the bark of Arjuna is utilized to remove numerous types of skin associated problems. It has antioxidant, anti-inflammatory and antimicrobial properties that assist in eliminating skin issues. In today’s short article, we will tell you which skin problems are eliminated by the powder of Arjun bark–.

Dry skin

Arjun bark is an efficient medicine for those with dry skin. Its extract assists in keeping moisture in the skin. In addition to this, it increases the production of sebum in the skin. Applying a face pack made from Arjun bark on the face removes the issue of dry skin and makes the face radiance.

Great Lines and Wrinkles

Applying arjuna bark on the face helps in preventing the signs of aging. It has abundant anti-oxidant properties that secure the skin from damage caused by totally free radicals. Using the bark of Arjuna on the skin tightens up the skin and gets rid of the problem of fine lines and wrinkles.

Itching

Arjuna bark has anti-inflammatory residential or commercial properties, which removes the issue of swelling and redness on the skin. Apart from this, the use of arjuna bark is likewise advantageous in the issue of pimples and itching on the face. It cools the skin and gets rid of the issue of itching.

Pimples

Arjun bark face pack is also an efficient home remedy in the problem of acne. It has antimicrobial residential or commercial properties that get rid of the problem of acne and pimples on the skin. This.

Spots

Arjun bark face pack is really effective for people who have the issue of imperfections on the face. Applying it on the face gets rid of the problem of acne. In addition to this, the bark of Arjuna is likewise beneficial to eliminate the dark spots and tanning of the face.

How to make Arjuna bark face pack

1. To make a face pack of Arjuna bark, take the powder of the bark of this tree.
2. Now add a spoonful of raw milk or honey to it.
3. Now use this paste on the affected area of your skin.
4. After this wash off with tidy water after 15-20 minutes [16]

Interactions with Organ Systems

Stomach

The methanolic extract of Arjuna appears to protect gastric tissue from lipopolysaccharide (LPS) from Heliobactor Pylori, which is understood to induce ulcers. [57] This protective result has been kept in mind versus alcohol (7 day preload), Dexamethasone (10 day preload), and diclofenac sodium (single dosage) where 100-200mg/ kg of an 80% ethanolic extract provided absolute security against ulcer development from Dexamethasone and alcohol, while 400mg/kg of an acute dosage gave absolute protection against Diclofenac Sodium. [58] The positive control in this study, Rantidine (35mg/kg Diclofenac, 50mg/kg alcohol, 4mg/kg Dexamethasone) likewise gave outright security, [58] and these protective effects versus Diclofenac have been reproduced with a methanolic extract and thought to be associated with the anti-oxidative capacity.

Ears

One research study noted that Arjuna extracts, especially acetonic extraction, was able to cause death of Staphylococcus aureus bacteria and encompassed Escherchia Coli, Acinetobacter sp, Proteus mirabilis, and Candida albicans; [60] the authors assumed that the results suggest that Arjuna may be useful against ear infections (although admittedly initial).

Liver

In isolated hepatocytes (HepG2), 5-100mcg/ mL of the water extract of Arjuna has the ability to concentration dependently decrease the biomarkers of oxidation induced by TERT (pro-oxidative agent), with complimentary radicals (ROS) and lipid peroxidation (TBARS) being lowered as much as 69% and 62% respectively. [61] The decrease of antioxidant enzymes by TERT was also significantly attenuated as much as 60% (SOD), 82% (Catalase), and Glutathione enzymes (62-65% for peroxidase and reductase; totally avoiding any decrease in Glutathione S-transferase). [61] These antioxidant impacts are believed to underlie outcomes achieved with 50mg/kg water extract of Arjuna for 7 days prior to CCL4 induced hepatotoxicity, where Arjuna substantially prevented the increase in GPT (dosage reliant reductions approximately 50mg/kg, no added advantage at 100mg/kg), stabilized ALP, and increased hepatic levels of antioxidant levels either to manage levels (Catalase and Glutathione S-Transferase) or above control (SOD), an effectiveness comparable to Vitamin C at the exact same oral doses.

Kidneys

250-500mg/ kg of a hydroalcoholic extract of Arjuna bark (not an oral study, however the comparable injected into perfused kidneys) appears to lower oxidation and concomitantly increase antioxidant enzymes (Catalase and Glutathione. A conservation of anti-oxidant enzymes in reaction to CCL4 is observed to be of similar strength to Vitamin C and has actually noted protective results in the kidneys of Alloxan-induced diabetic rats at oral dosages of 250-500mg/ kg of the water extract.

Particles that are found in Arjuna that have actually been kept in mind to put in protective impacts on kidney cells include Casuarinin, a tannin structure, with more effectiveness than the water soluble kind of Vitamin E known as Trolox.

Urinary Tract

In vitro, Arjuna seems able to decrease development rates of calcium-based kidney stones (calcium oxalate and calcium phosphate evaluated) with the butanol extract being most efficient.

Testicles

One study using arsenic-induced testicular damage in rats noted that 4 days pretreatment with isolated Arjunolic acid can avoid oxidative testicular damange and histological changes in action to arsenic. This study noted that, in vitro, the antioxidant capacity of Arjunolic Acid peaked at a focused of 0.4 mg/mL and this appeared to associated with an oral consumption of 20mg/kg (as 50mg/kg did not give additional protective benefits) and that the total protective benefit was near outright, and sligtly less reliable than 100mg/kg Vitamin C. [17]

Preventative measures:

During Pregnancy and Breastfeeding: There is no evidence that Terminalia Arjuna is possibly unsafe during pregnancy & & breastfeeding. Please remain on the safe side and avoid utilizing it during pregnancy.

Bleeding Conditions: It might slow blood clotting and risk bleeding and bruising in people with bleeding disorders.

Surgery: Terminalia may disrupt blood glucose control and increase the danger of bleeding throughout surgical treatment. So stop utilizing it prior to two weeks before a scheduled surgical treatment.

Storage:

Two years if sealed and save far from direct sunlight. [18]

Conclusion

The everlasting interest in medicinal plants has caused the discovery of new chemical constituents and medicinal actions of arjuna. Its efficacy as an anti-ischemic agent, a powerful antioxidant, and an antiatherogenic agent has actually been amply demonstrated in numerous experimental and medical research studies. Nevertheless, major lacunae of these research studies include the lack of phytochemical standardization of the extract, bioavailability research studies, and well-designed studies to assess its long-lasting toxicity impacts. Its specific role in primary/secondary coronary avoidance needs to be investigated. In addition to this, research studies to look for the effect of arjuna on CYP450 enzymes and its interactions with other drugs like statin, aspirin, angiotensin-converting enzyme (ACE) inhibitors, and β-blocker need to be developed. Increasing the awareness concerning its medicinal use can provide an instructions to the doctors to respond to the challenges in treating heart diseases. [19]

Recommendations

1. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4220499/
2. https://www.indigo-herbs.co.uk/natural-health-guide/benefits/arjuna
3. https://en.wikipedia.org/wiki/Terminalia_arjuna
4. http://www.ecoindia.com/flora/trees/arjun-tree.html
5. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5198828/
6. https://www.researchgate.net/publication/320634680_INAA_of_essential_micronutrients_in_Terminalia_arjuna_bark_powder_a_versatile_heart_tonic
7. https://www.pharmacy180.com/article/arjuna-317/
8. https://www.healthline.com/nutrition/arjunarishta
9. https://www.sciencedirect.com/science/article/pii/S1110863013000888
10. https://www.onlymyhealth.com/arjun-fruit-benefits-1652761281
11. https://www.netmeds.com/health-library/post/arjunarishta-benefits-uses-ingredients-method-dosage-and-side-effects
12. https://www.herbalreality.com/herb/arjuna/
13. https://www.banyanbotanicals.com/info/plants/ayurvedic-herbs/arjuna-benefits/
14. https://aiwo.com/blogs/blog/terminalia-arjuna-benefits-sources-and-side-effects
15. https://wellversed.in/blogs/articles/what-is-arjunarishta-all-you-need-to-know
16. https://hindustannewshub.com/beauty-tips/these-5-skin-problems-are-removed-by-the-bark-of-arjuna-know-how-to-make-its-face-pack/
17. https://examine.com/supplements/terminalia-arjuna/research
18. https://chiltanpure.com/product/arjuna-powder/
19. https://www.sciencedirect.com/science/article/pii/S222541101630236X