Improved Attack on the Cellular Authentication and Voice Encryption Algorithm

We present new cryptanalysis of the Telecommunications hash algorithm known as Cellular Authentication and Voice Encryption Algorithm (CAVE). The previous guess-and-determine style reconstruction attack requires $2^{91}$ (resp. $2^{93}$) evaluations of CAVE-4 (resp. CAVE-8) to find a single valid pre-image (one which satisfies the input redundancy). Here we present a new attack that finds emph{all} valid pre-images with effort equivalent to around $2^{72}$ evaluations of the algorithm for both CAVE-4 and CAVE-8

Investment-Specific Technology Shocks in a Small Open Economy

In this paper we examine the behavioral responses of key macroeconomic variables in Canada to exogenous innovations to investment specific technology. This is done by developing a stylized international real business cycle model which is simulated to explore its ability to shed new light on the dynamic behavior of the standard small open economy. The results indicate that this model can quantitatively replicate the key dynamic features of the post-war Canadian economy, and thus shocks to investment-specific technology can be considered an important propagation mechanism for studying and understanding modern macroeconomic dynamics in small open economies. Moreover, when the model was augmented with an endogenous utilization rate it was able to generate the counter-cyclical behavior of the external accounts - without appealing to an adjustment cost parameter and/or a propagation mechanism whose volatility and persistence are artificially low.Endogenous rate of time preference; Investment-specific shocks; Relative price of investment goods

Meeting the Needs of Central American Migrant Youth in Schools

The goal of this qualitative inquiry was to explore the barriers that Central American migrant youth face in California education settings while using the power of participatory action research to harness the direct voices of this unique and rapidly growing population. The current study examined narratives from 12 former students (ages 17-23) who migrated from Central America and enrolled in U.S. public schools during their adolescence. Participants were recruited by former staff and their peers using social media. Qualitative inquiry about their educational experiences was conducted via semi- structured interviews with the support of peer researchers using a questionnaire focused on themes of students’ educational history, country of origin, age of arrival, socioeconomic status, mental health, and school supports. Interviews were transcribed and coded thematically. Results showed that the developmental timing of migration, country of origin, family history, and reason for immigrating all had an impact on adjustment to school and mental health. Most notably, results indicated that the effects of mental health permeated all themes explored in this study suggesting that behavioral health care and social-emotional support services are an unmet need in this population. The research team has concluded that the diverse needs of this population require comprehensive efforts and supports in the school setting and have direct implications for social work in developing supports, policy, and best practices in direct service to support the complex needs of this population

Investment-Specific Technology Shocks in a Small Open Economy

This paper re-examines the behavioral responses of key macroeconomic variables in Canada to exogenous shocks to the relative price of investment goods. It does so by developing a stylized two-sector real business cycle model which is simulated to explore its ability to shed new light on the dynamic behavior of the standard small open economy. The results indicate that this model can qualitatively and quantitatively replicate the dynamic features of the Canadian economy, and thus shocks to investment-specific technology can be considered an important propagation mechanism for studying and understanding modern macroeconomic dynamics in small open economies.Endogenous rate of time preference, International real business cycle, Investment-specific shocks, Relative price of investment goods, Small open economy

Applications of the covering property axiom

The purpose of this work is two-fold. First, we present some consequences of the Covering Property Axiom CPA of Ciesielski and Pawlikowski which captures the combinatorial core of the Sacks\u27 model of the set theory. Second, we discuss the assumptions in the formulation of different versions of CPA.;As our first application of CPA we prove that under the version CPAgamecube of CPA there are uncountable strong gamma-sets on R . It is known that Martin\u27s Axiom (MA) implies the existence of a strong gamma-set on R . Our result is interesting since that CPAgamecube implies the negation of MA.;Next, we use the version CPAgameprism of CPA to construct some special ultrafilters on Q . An ultrafilter on Q is crowded provided it contains a filter basis consisting of perfect sets in Q . These ultrafilters have been constructed under various hypotheses. We study the properties of being P-point, Q-point, and o1-OK point and their negations; and prove under CPAgameprism the existence of an o1-generated crowded ultrafilter satisfying each consistent combination of these properties. We also refute an earlier claim by Ciesielski and Pawlikowski by proving under CPAgameprism that there are 2c -many crowded c -generated Q-points.;We also study various notions of density, central to the foundation of CPA and defined in the set of all perfect subsets of a Polish space X . These notions involve the concepts of perfect cube and iterated perfect set on Ca . If X is a Polish space, we say that F ⊆ Perf( X ) is alpha-cube (alpha-prism) dense provided for every continuous injection f : Ca → X there exists a perfect cube (iterated perfect set) C ⊆ Ca such that f[C] ∈ F .;We prove that for every alpha \u3c o1 and every Polish space X there exists a family F such that F is beta-prism dense for every beta \u3c alpha but &vbm0;X\⋃ F&vbm0;=c . Therefore, any attempt of strengthening of axiom CPAprism by replacing prism-density with any proper subclass of these densities leads to a false statement. The proof of this theorem is based in the following result: Any separately nowhere-constant function defined on a product of Polish spaces is one-to-one on some perfect cube

Student engagement with resources as observable signifiers of success in practice based learning

Practice-based learning activities with a focus on Science, Technology, Art, Math and Engineering (STEAM) are providing new opportunities for teaching these subjects. However, we lack widely accepted ways of assessing and monitoring these practices to inform educators and learners and enable the provision of effective support. Here, we report the results from a study with 15 teenage students taking part in a 2-day Hack. We present results from analysis of video data recording collaborative working between groups of students. The analysis of the video data is completed using the ERICAP analytical framework (Luckin et al., 2017) based on ecology of resources and interactive, constructive, active and passive engagement concepts. The results illustrate the differences between students' engagement with resources which might be utilized as signifiers of student success in similar learning environments.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Knowledge and Attitudes towards Sickle Cell Disease Screening: A Study of Members of the UK Sickle Cell Society

Over the past fifty years there has been an increase in the number of people in the UK who have a Sickle Cell Disorder (SCD) or are carriers. This increase has led to an expansion in research in this area; however one particular area that has not been researched rigorously is people’s knowledge, attitudes and behaviour towards SCD and genetic screening. Members of the Sickle Cell Society provided an ideal population for this exploratory study looking at people’s knowledge, attitudes and behaviours towards the SCD and genetic screening. This paper reports on the process and findings of this postal study