1,720,975 research outputs found
Very low cost chaos-based entropy source for the retrofit or design augmentation of networked devices
No full textModern cryptographic protocols require good entropy sources. Unfortunately, many networked devices lack subsystems dedicated to this task, being potentially susceptible to random number generator (RNG) attacks. Yet, most of these systems allow software upgrades and host communication ports, providing the option of a retrofit. This work illustrates how chaotic dynamics can be used to design a sub-10$ entropy source capable of an over 48kbit/s rate and offering multiple serial communication abilities. Operation is based on a standard microcontroller and exploits a loop built around one of its analog to digital converters (ADCs). The design offers self-testing features and enables an experimental validation of some recent results on the choice of the best state quantization function to employ when using chaotic maps as RNGs
Very low cost entropy source based on chaotic dynamics retrofittable on networked devices to prevent RNG attacks
No full textGood quality entropy sources are indispensable in most modern cryptographic protocols. Unfortunately, many currently deployed networked devices do not include them and may be vulnerable to Random Number Generator (RNG) attacks. Since most of these systems allow firmware upgrades and have serial communication facilities, the potential for retrofitting them with secure hardware-based entropy sources exists. To this aim, very low-cost, robust, easy to deploy solutions are required. Here, a retrofittable, sub 10$ entropy source based on chaotic dynamics is illustrated, capable of a 32 kbit/s rate or more and offering multiple serial communication options including USB, I2C, SPI or USART. Operation is based on a loop built around the Analog to Digital Converter (ADC) hosted on a standard microcontroller
Partial tendon tear as unusual cause of trigger finger. a case report
Full text linkWe report a case of post-traumatic trigger finger due to a partial longitudinal tear of the flexor digitorum superficialis. The suspect came from the clinical history and the young age of the patient. It was successfully treated with tendon flap suture and pulley A1 release
Salter-Harris type III and IV displaced fracture of the hallux in young gymnasts: A series of four cases at 1-year follow-up
No full textThe purpose of this study was to describe four exceptional cases of Salter-Harris type III and IV fractures of the proximal phalanx of the hallux in young high-level gymnasts. All gymnasts underwent the same mechanism of injury of hyperadduction, which indicates a role of the abductor hallucis muscle in the genesis and displacement of these fractures. An open reduction and internal fixation was performed to achieve an anatomical reduction and avoid chronic disability. At 1-year follow-up, all patients had an excellent American Orthopaedic Foot and Ankle Society (AOFAS) score (100 points), and there was no shortening or angulation of the first ray and no evidence of degenerative joint disease on X-ray. Moreover, all the gymnasts had returned to pre-injury levels of sporting activity. To our knowledge, there are no previous studies that address these types of injuries and how they are handled in gymnasts.The purpose of this study was to describe four exceptional cases of Salter-Harris type III and IV fractures of the proximal phalanx of the hallux in young high-level gymnasts. All gymnasts underwent the same mechanism of injury of hyperadduction, which indicates a role of the abductor hallucis muscle in the genesis and displacement of these fractures. An open reduction and internal fixation was performed to achieve an anatomical reduction and avoid chronic disability. At 1-year follow-up, all patients had an excellent American Orthopaedic Foot and Ankle Society (AOFAS) score (100 points), and there was no shortening or angulation of the first ray and no evidence of degenerative joint disease on X-ray. Moreover, all the gymnasts had returned to pre-injury levels of sporting activity. To our knowledge, there are no previous studies that address these types of injuries and how they are handled in gymnasts
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Isokinetic flexion strength recovery after ACL reconstruction. a comparison between all inside graft-link technique and full tibial tunnel technique
No full textIntroduction: Recently, a new minimally invasive single bundle technique for anatomic ACL reconstruction has been described, called the ‘All-Inside graft-link technique’. One of the advantages of this procedure is the reduced morbidity at the donor site as the graft choice is the quadrupled semitendinosus, thus sparing the gracilis tendon. The aim of this study was to evaluate isokinetic flexion strength recovery in patients who underwent a gracilis sparing technique compared to those with a full-tibial tunnel technique using a doubled gracilis and semitendinosus tendons (DGST) graft. Methods: Patients were divided into two groups: Group A (22 patients) who underwent ACL reconstruction performed with an All-Inside graft-link technique; Group B (22 patients) who underwent ACL reconstruction with an Out-In technique and DGST graft. At a mean follow-up of 13 months, quadriceps and hamstring isokinetic peak torque deficits were recorded. Results: In group A, the mean side to side peak torque flexion difference between the operated and non-operated limbs was −3% and the mean torque at 30° was −7.5% at high angular velocity (180°/sec); the mean peak flexion torque was 7.2% and the mean torque at 30° was 3.1% at low angular velocity (60°/sec). In group B, the mean side to side peak flexion torque was −3.5% and the mean torque at 30° was −7.6% at high angular velocity (180°/sec); the mean peak flexion torque was −7.2% and the mean torque at 30° was −11% at low angular velocity (60°/sec). A statistically significant difference was found between the two groups at lower angular velocity both for the mean peak flexion torque and the mean torque at 30° (p = 0.009), with better results in the study group. Discussion/conclusion: Gracilis sparing technique is a minimally invasive technique for ACL reconstruction and yielded a significantly better flexion strength recovery at lower angular velocity compared to a full tibial tunnel technique with DGST for ACL reconstruction
Prevalence and Classification of Injuries of Anterolateral Complex in Acute Anterior Cruciate Ligament Tears
No full textTo report on the prevalence of injuries of the lateral compartment occurring in cases of apparently isolated acute anterior cruciate ligament (ACL) tears and to present a classification system of anterolateral complex injuries based on the data obtained
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