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Warrants (Details Narrative) - USD ($)	Apr. 08, 2019	Jul. 22, 2016	Jun. 02, 2016	Apr. 30, 2021	Apr. 30, 2020
Number of common stock shares sold	1,542,000
Warrant liabilities
Pre-funded Warrants [Member]
Warrant to purchase shares common stock	3,385,680
Warrant exercise price per share	$ 0.01
Common Warrants [Member]
Warrant to purchase shares common stock	4,927,680
Warrant exercise price per share	$ 3.85
Class of warrant or right, expiration period	5 years
Warrants [Member]
Number of exercised warrants				732,500
June Purchase Agreement [Member]
Number of common stock shares sold			20,850
Warrant to purchase shares common stock			7,298
Class of warrant or right, number of securities called by each warrant or right			0.35
Combined purchase price per share			$ 92.00
Warrant exercise price per share			$ 121.60
Class of warrant or right, expiration period			5 years
Number of exercised warrants
Second Amended Purchase Agreement [Member]
Number of common stock shares sold		29,750
Warrant to purchase shares common stock		8,925
Class of warrant or right, number of securities called by each warrant or right		0.30
Combined purchase price per share		$ 135.00
Warrant exercise price per share		$ 187.20
Class of warrant or right, expiration period		5 years
Number of exercised warrants

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Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

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Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=123467817&loc=d3e21475-112644

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Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=123874694&loc=d3e19207-110258

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