Distinguishing multiplications from squaring operations

Abstract. In this paper we present a new approach to attacking a modular exponentiation and scalar multiplication based by distinguishing multiplications from squaring operations using the instantaneous power consumption. Previous approaches have been able to distinguish these operations based on information of the specific implementation of the embedded algorithm or the relationship between specific plaintexts. The proposed attack exploits the expected Hamming weight of the result of the computed operations. We extrapolate our observations and assess the consequences for elliptic curve cryptosystems when unified formulae for point addition are used

Trauma exposure, PTSD and psychotic-like symptoms in post-conflict Timor Leste: an epidemiological survey.

BACKGROUND: Studies in developed countries indicate that psychotic-like symptoms are prevalent in the community and are related to trauma exposure and PTSD. No comparable studies have been undertaken in low-income, post-conflict countries. This study aimed to assess the prevalence of psychotic-like symptoms in conflict-affected Timor Leste and to examine whether symptoms were associated with trauma and PTSD. METHODS: The Psychosis Screening Questionnaire and the Harvard Trauma Questionnaire (assessing trauma exposure and PTSD) were administered in an epidemiological survey of 1245 adults (response rate 80.6%) in a rural and an urban setting in Timor Leste. We defined PSQ screen-positive cases as those people reporting at least one psychotic-like symptom (paranoia, hallucinations, strange experiences, thought interference, hypomania). RESULTS: The prevalence of PSQ screen-positive cases was 12 percent and these persons were more disabled. PSQ cases were more likely to reside in the urban area, experienced higher levels of trauma exposure and a greater prevalence of PTSD. PTSD only partially mediated the relationship between trauma exposure and psychotic-like symptoms. CONCLUSIONS: Psychotic-like symptoms may be prevalent in countries exposed to mass conflict. The cultural and contextual meaning of psychotic-like symptoms requires further inquiry in low-income, post-conflict settings such as Timor Leste.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are

All-or-Nothing Transforms as a Countermeasure to Differential Side-Channel Analysis

All-or-Nothing Encryption was introduced by Rivest as a countermeasure to brute force key search attacks. This work identifies a new application for All-or-Nothing Transforms, as a protocol-level countermeasure to Differential Side-Channel Analysis (DSCA). We describe an extension to the All-or-Nothing protocol, that strengthens the DCSA resistance of the cryptosystem. The resultant scheme is a practical alternative to Boolean and arithmetic masking, used to protect implementations of encryption and decryption operations on electronic devices

Development of the “Recovery from Eating Disorders for Life” Food Guide (REAL Food Guide) - a food pyramid for adults with an eating disorder

Abstract Background There is limited evidence to inform nutrition and dietetic interventions for individuals with eating disorders even though it is recommended as an essential part of multidisciplinary management. There is minimal guidance, an absence of standardised nutrition educational material, and no research on how best to educate patients on healthy eating and how to achieve nutrition adequacy. Therefore the REAL Food Guide was developed. Methods The REAL Food Guide is a pyramid with four layers and key nutrition messages beside each layer that was conceived to address gaps in nutrition education and intervention for individuals with eating disorders. Written and verbal consumer feedback was obtained from consumers receiving treatment regarding the acceptability and usefulness of the REAL Food Guide. A unique database was developed to reflect the types of foods and realistic portion sizes that patients are likely to select. This database was used for nutrition modelling to assess the nutrition adequacy of three meal patterns (meat containing, vegetarian and semi-vegan) for both weight maintenance and weight regain. Each meal pattern was compared to the Nutrient Reference Values for Australia and New Zealand. Results Nutritional analysis demonstrated nutritional adequacy of meal patterns for energy, macronutrients and most micronutrients when the recommended number of serves from the REAL Food Guide were assessed. All meal patterns were adequate in micronutrients except for the semi-vegan meal pattern that was inadequate in vitamin D. Feedback from individuals with eating disorders demonstrates the nutrition education tool was acceptable to them as they felt it was more helpful for their recovery than general nutrition guidelines. Conclusion The REAL Food Guide is a comprehensive and user-friendly guide that clinicians can use to educate patients about components of a balanced and healthy diet. The guide can educate all eating disorder clinicians, including those who are new to the field, about the basics of nutrition. Clinicians using the guide can be confident that, if followed, patient’s energy and nutritional requirements will be met and important nutrition education messages are reinforced, that are tailored to the beliefs and concerns of individuals with eating disorders

Additional file 1: of Development of the “Recovery from Eating Disorders for Life” Food Guide (REAL Food Guide) - a food pyramid for adults with an eating disorder

Portion Size. (DOCX 10488 kb

Additional file 2: of Development of the “Recovery from Eating Disorders for Life” Food Guide (REAL Food Guide) - a food pyramid for adults with an eating disorder

Nutrition analysis and food modelling. (DOCX 351 kb