Acsesor: A New Framework for Auditable Custodial Secret Storage and Recovery

Custodial secret management services provide a convenient centralized user experience, portability, and emergency recovery for users who cannot reliably remember or store their own credentials and cryptographic keys. Unfortunately, these benefits are only available when users compromise the security of their secrets and entrust them to a third party. This makes custodial secret management service providers ripe targets for exploitation, and exposes valuable and sensitive data to data leaks, insider attacks, and password cracking, among other dangers. Several password managers and cryptocurrency wallets today utilize non-custodial solutions, where their users are in charge of a high-entropy secret, such as a cryptographic secret key or a long passphrase, that controls access to their data. One can argue that these solutions have a stronger security model, as the service provider no longer constitutes a single point of trust. However, the obvious downside is that it is very difficult for people to store cryptographic secrets reliably, making emergency recovery a serious problem. We present Acsesor: a new framework for auditable custodial secret management with decentralized trust. Our framework offers a middle-ground between a fully custodial (centralized) and fully non-custodial (user-managed/distributed) recovery system: it enhances custodial recovery systems with cryptographically assured access monitoring and a distributed trust assumption. In particular, the Acsesor framework distributes the recovery process across a set of (user-chosen) guardians. However, the user is never required to interact directly with the guardians during recovery, which allows us to retain the high usability of centralized custodial solutions. Additionally, Acsesor retains the strong resilience guarantees that custodial systems provide against fraud attacks. Finally, by allowing the guardians to implement flexible user-chosen response policies, Acsesor can address a broad range of problem scenarios in classical secret management solutions. For example, a slow recovery policy, where the guardians wait for a predefined time until responding, can replace the cumbersome passphrases many cryptocurrency wallets implement today for emergency recovery. We also instantiate the Acsesor framework with a base protocol built of standard primitives: standard encryption schemes and privacy-preserving transparency ledgers. Our construction requires no persistent storage from its users and supports an expansive array of configuration options and extensions

Sex Differences in the Superficial Femoral Artery Occlusion Pressure

The measurement of arterial occlusion pressure (AOP) prior to the use of blood flow restriction during exercise is recommended. Not all previous studies that have included both male and female participants have reported sex differences in AOP. PURPOSE: The purpose of this study was to compare the superficial femoral artery AOP of the dominant and non-dominant legs between males and females. METHODS: Ultrasound (GE LOGIQ) was used to detect blood flow through the superficial femoral artery of both legs in a random order in 20 males and 20 females. Circumference of the upper thigh, leg volume, and skinfold thickness were measured in both legs. Blood pressure was continuously monitored using a CNAP device. An inflatable cuff was placed around the upper thigh. The cuff was inflated to 50 mmHg and then inflated continuously (10 mmHg/10 s) until arterial blood flow and pulse waves were no longer detectable by the ultrasound. The AOP was then measured in the opposite leg. The AOP data were analyzed with a mixed model analysis of variance while maintaining a family-wise p-value of 0.05. RESULTS: The AOP of the dominant leg in males (209.4 ± 29.4 mmHg) and females (212.3 ± 8.3 mmHg) were not significantly different (p=0.844). Likewise, the AOP of the non-dominant leg in males (206.8 ± 32.5 mmHg) was not significantly different (p=0.804) than the AOP in the non-dominant legs of females (203.5 ± 50.9 mmHg). When combining the data for the dominant and non-dominant legs, the average AOP for males (208.1 ± 30.6 mmHg) and females (207.9 ± 53.1 mmHg) were not significantly different (p=0.986). Thigh circumference was the only variable that significantly (p=0.027) contributed to AOP. On the average the thigh circumference in the dominant and non-dominant legs of males (59.6 ± 5.5; 59.2 ± 5.2 cm) was greater than that for females (56.0 ± 2.9; 55.6 ± 3.2 cm), respectively. There were no sex differences in thigh skinfold thickness or thigh volume between males and females in either the dominant or non-dominant legs. CONCLUSION: There were no significant differences in AOP of the superficial femoral artery of the dominant and non-dominant legs between males females despite males having larger legs. Factors other than limb circumference likely have a role in determining AOP

Differences in Arterial Occlusion Pressure of the Superficial Femoral Artery Between the Dominant and Non-Dominant Legs

The arterial occlusion pressure (AOP) is dependent on limb circumference. Previous research seldom reports the AOP of both limbs. PURPOSE: The purpose of this study was to compare the superficial femoral artery AOP measured in the dominant and non-dominant legs. METHODS: Ultrasound (GE LOGIQ) was used to detect blood flow through the superficial femoral artery of both legs in a random order in 20 males and 20 females. Circumference of the upper thigh, leg volume, and skinfold thickness were measured in both legs. Blood pressure was continuously monitored using a CNAP device. An inflatable cuff was placed around the upper thigh. The cuff was inflated to 50 mmHg and then inflated continuously (10 mmHg/10 s) until arterial blood flow and pulse waves were no longer detectable by the ultrasound. The AOP was then measured in the opposite leg. The AOP data were analyzed with a mixed model analysis of variance while maintaining a family-wise p-value of 0.05. RESULTS: In males, the AOP of the dominant (209.4 ± 29.4 mmHg) and non-dominant legs (206.8 ± 32.5 mmHg) were not significantly different (p=0.790). Likewise, in females the AOP of the dominant (212.3 ± 58.3 mmHg) and non-dominant legs (203.5 ± 50.9 mmHg) were not significantly different (p=0.386). When combining the data for males and females, the AOP of the dominant (210.9 ± 45.6 mmHg) and non-dominant legs (205.2 ± 40.7 mmHg) were not significantly different (p=0.412). Thigh circumference was the only variable that significantly (p=0.027) contributed to AOP. In both males and females, there were no differences in thigh skinfold thickness, circumference, and volume between the dominant and non-dominant legs. The dominant leg was larger in 24 (60%) of the subjects; the larger leg had a higher AOP in 19 (47.5%) of the subjects; and the dominant leg had a higher AOP in 26 (65%) of the subjects. Although the AOP between the dominant and nondominant legs was not statistically significant, the largest difference in AOP between the two legs was 124 mmHg. CONCLUSION: There were no significant differences in AOP of the superficial femoral artery between the dominant and non-dominant legs in either males or females. Because of the potentially larger differences in the AOP between the two legs, we recommend measuring the AOP in both limbs when using blood flow restriction during exercise

Reliability of Arterial Occlusion Pressure Measurements Using Two Different Cuff Inflation Protocols

Although previous studies have used two different cuff inflation protocols to measure AOP, no studies have reported the reliability of AOP measurements using both protocols. PURPOSE: The purpose of this study was to evaluate the reliability of two measurements of AOP in the superficial femoral artery using two different cuff inflation protocols. METHODS: Ultrasound (GE LOGIQ) was used to detect blood flow through the superficial femoral artery of both legs in 20 males and 20 females. The AOP of the artery was measured twice in each leg. The artery was occluded using a continuous (CONT) cuff inflation protocol in one leg and an increment (INCR) cuff inflation protocol in the opposite leg. The CONT protocol involved inflating the cuff to 50 mmHg then continuously inflating the cuff at a rate of 10 mmHg/10 s until blood flow could no longer be detected using the ultrasound. The INCR protocol involved initially inflating the cuff to 50 mmHg for 30 s, and then deflating the cuff for 10 s. The cuff was then inflated incrementally with each subsequent inflation increasing by 30 mmHg for 30 s followed by deflating the cuff for 10 s. Once blood flow was occluded, cuff pressure was decreased in increments of 10 mmHg until there was evidence of blood flow. The cuff was then gradually inflated until blood flow was no longer detected. The pressure at which blood flow could no longer be detected was recorded as the AOP. The data were analyzed with a mixed model analysis of variance while maintaining a family-wise p-value of 0.05. RESULTS: The difference in the two measurements of AOP using the CONT and INCR cuff inflation protocols in males (0.9 ± 5.4 and 0.5 ± 5.1 mmHg) and females (1.9 ± 11.4 and 2.3 ± 12.2 mmHg), or when combining the data from males and females (0.4 ± 8.9 and 0.9 ± 9.3 mmHg), respectively, were not statistically significant. The correlations between the two measurements of AOP using the CONT and INCR cuff inflation protocols all exceeded 0.99. CONCLUSION: Measurements of AOP using a continuous or increment cuff inflation protocol are highly reliable. Either cuff inflation protocol can be used when making multiple measurements of AOP

Differences in Arterial Occlusion Pressure Using Two Different Cuff Inflation Protocols

The occlusion pressure used during blood flow restriction during exercise is based on the arterial occlusion pressure (AOP). Although previous studies have measured AOP using two different cuff inflation protocols, no studies have compared the AOP measured using both protocols. PURPOSE: The purpose of this study was to compare the superficial femoral artery AOP when measured using two different cuff inflation protocols. METHODS: Ultrasound (GE LOGIQ) was used to detect blood flow through the superficial femoral artery of both legs in 20 males and 20 females. An inflatable cuff was placed on the upper thigh. The superficial femoral artery was occluded using two different cuff inflation protocols in a random order in both legs. The continuous (CONT) protocol involved inflating the cuff to 50 mmHg then continuously inflating the cuff at a rate of 10 mmHg/10 s until blood flow could no longer be detected using the ultrasound. The incremental (INCR) protocol involved inflating the cuff to 50 mmHg for 30 s, and then deflating the cuff for 10 s. The cuff was then inflated incrementally with each subsequent inflation increasing by 30 mmHg for 30 s followed by deflating the cuff for 10 s. Once blood flow was occluded, cuff pressure was decreased in increments of 10 mmHg until there was evidence of blood flow. The cuff was then gradually inflated until blood flow was no longer detected. RESULTS: In males, the AOP measured in the dominant (209.4 ± 29.4; 208.2 ± 27.1) and non-dominant (206.8 ± 32.5; 206.2 ± 32.7) legs using the CONT and INCR cuff inflation protocols, respectively, were not significantly different (p\u3e0.05). Likewise, in females the AOP measured in the dominant (212.3 ± 58.3; 213.7 ± 53.9) and non-dominant (203.5 ± 50.9; 207.0 ± 50.2) legs using the CONT and INCR protocol, respectively, were not significantly different (p\u3e0.05). When combining male and female data, there were no significant differences in the AOP between the CONT and INCR cuff inflation protocols in either leg or when combining legs. CONCLUSION: Using a continuous or incremental protocol for occluding the superficial femoral artery resulted in similar AOP values. Either protocol can be used in future research as well as in settings where AOP is determined prior to the use of blood flow restriction during exercise

Differences in Arterial Occlusion Pressure as Measured using Ultrasound and a Hand-Held Doppler Device

In the research lab and clinical settings, expensive ultrasound machines are used to measure arterial occlusion pressure (AOP) prior to the use of blood flow restriction during exercise. Alternatively, inexpensive hand-held Doppler ultrasound devices may be used to measure AOP in various applications and settings. PURPOSE: The purpose of this study was to compare the superficial femoral artery AOP as measured using ultrasound and a hand-held Doppler device. METHODS: Participants included 20 males and 20 females. An inflatable cuff was placed on the upper thigh. The superficial femoral artery was occluded by inflating the cuff to 50 mmHg then continuously inflating the cuff at a rate of 10 mmHg/10 s. A GE LOGIQ ultrasound was used to detect blood flow in the superficial femoral artery just below the cuff. A hand-held Doppler device was used simultaneously to detect blood flow (pulse waves) at the anterior medial malleolar artery of the ankle. The pressure at which blood flow could no longer be detected using the ultrasound and the hand-held Doppler were recorded as the AOP. The measurement of AOP using both devices simultaneously was performed on both legs in a random order. The data were analyzed with a mixed model analysis of variance while maintaining a family-wise p-value of 0.05. RESULTS: On the average, the AOP measured using the hand-held Doppler device was significantly (pCONCLUSION:Although the differences in the AOP measured using the Ultrasound and the hand-held Doppler in both legs in males and females was statistically significant, for all practical purposes, the small differences were of not practical importance. In settings in which blood flow restriction during exercise is employed, a hand-held Doppler device is a viable alternative to using expensive ultrasound machines to measure AOP

Phage Hunting at the University of Mary Washington: Genome Annotation of Hari and JackRabbit

Bacillus thuringiensis subspecies Kurstaki (BTK) is often used as a microbial insecticide for pest control and as a simulant for Bacillus anthracis in biowarfare and bioterrorism studies. Students in 2021 Phage Hunters class at University of Mary Washington isolated nine bacteriophages using the host Bacillus thuringiensis subspecies Kurstaki. Two phages, Hari and Jackrabbit, were sent to SEAPHAGES for sequencing are currently being annotated in the lab during the Spring semester. Hari was found in a soil sample obtained from King George, VA while JackRabbit was isolated from Linton, VA. Both samples were isolated from enriched cultures. Hari has a genome length of 161,978 bp, which auto-annotated with 286 features, and a direct terminal repeat of 2,633 bp. Hari is most similar to DIGNKC, SBP8a and PPIsBest by BLAST. JackRabbit has a genome length of 161,552 bp, which auto-annotated with 288 features, and a direct terminal repeat of 2,821 bp

Concert recording 2019-04-11

[Track 1]. Concert etude / Alexander Goedicke -- [Track 2]. Sonata VIII. I. Prelude: Largo II. Allemande: Allegro / Arcangelo Corelli -- [Track 3]. Oliver\u27s birthday / Bruce Broughton -- [Track 4]. Concerto [abridged] / Alexander Arutunian -- [Track 5]. Aria con variazioni / Georg Frederic Handel -- [Track 6]. Sonata for trumpet and piano. I. Lento, Allegro molto / Eric Ewazen -- [Track 7]. Concerto in E♭. I. Allegro / J.B.G. Neruda -- [Track 8]. Suite. II. Air [Track 9]. I. Prelude / William P. Latham

Measuring Brachial Artery Occlusion Pressure Using a Hand-held Doppler and Pulse Oximeter

The measurement of arterial occlusion pressure (AOP) is recommended for the safe and effective use of blood flow restriction (BFR) during training. PURPOSE: This study compared measurements of brachial artery AOP using Doppler ultrasound (US), a hand-held Doppler (HHDOP) and a pulse oximeter (PO). METHODS: The AOP of the brachial artery was measured simultaneously using US, HHDOP, and a PO in the dominant arm of males (n=36) and females (n=49). The blood flow restriction cuff was inflated using a continuous cuff inflation protocol. RESULTS: A mixed model ANOVA revealed small but significant (p \u3c 0.05) overall main effects (combined males and females) between AOP measured using US (119.8 ± 13.2 mmHg), HHDOP (119.1 ± 13.1 mmHg) and PO (118.0 ±13.2 mmHg), and between males (125.3 ± 13.1 mmHg) and females (114.3 ± 11.1 mmHg). The differences in AOP between males and females was consistent across all three methods of measuring AOP (US, HHDP, PO) and may be attributed to sex differences in limb circumference and systolic blood pressure. The small overall difference between US and HHDOP (0.74 ± 2.7 mmHg) was not significant but the difference between US and PO (1.81 ± 3.3 mmHg) measures of AOP was significant (