Threshold Implementations of all 3x3 and 4x4 S-boxes

Side-channel attacks have proven many hardware implementations of cryptographic algorithms to be vulnerable. A recently proposed masking method, based on secret sharing and multi-party computation methods, introduces a set of sufficient requirements for implementations to be provably resistant against first-order DPA with minimal assumptions on the hardware. The original paper doesn\u27t describe how to construct the Boolean functions that are to be used in the implementation. In this paper, we derive the functions for all invertible $3 \times 3$, $4 \times 4$ S-boxes and the $6 \times 4$ DES S-boxes. Our methods and observations can also be used to accelerate the search for sharings of larger (e.g. $8 \times 8$) S-boxes. Finally, we investigate the cost of such protection

No tradeoff between confidentiality and performance: An analysis on H.264/SVC partial encryption

Agency for Science, Technology and Research (A*STAR

Automatic registration with continuous pose updates for marker-less surgical navigation in spine surgery

Established surgical navigation systems for pedicle screw placement have been proven to be accurate, but still reveal limitations in registration or surgical guidance. Registration of preoperative data to the intraoperative anatomy remains a time-consuming, error-prone task that includes exposure to harmful radiation. Surgical guidance through conventional displays has well-known drawbacks, as information cannot be presented in-situ and from the surgeon's perspective. Consequently, radiation-free and more automatic registration methods with subsequent surgeon-centric navigation feedback are desirable. In this work, we present a marker-less approach that automatically solves the registration problem for lumbar spinal fusion surgery in a radiation-free manner. A deep neural network was trained to segment the lumbar spine and simultaneously predict its orientation, yielding an initial pose for preoperative models, which then is refined for each vertebra individually and updated in real-time with GPU acceleration while handling surgeon occlusions. An intuitive surgical guidance is provided thanks to the integration into an augmented reality based navigation system. The registration method was verified on a public dataset with a median of 100% successful registrations, a median target registration error of 2.7 mm, a median screw trajectory error of 1.6°and a median screw entry point error of 2.3 mm. Additionally, the whole pipeline was validated in an ex-vivo surgery, yielding a 100% screw accuracy and a median target registration error of 1.0 mm. Our results meet clinical demands and emphasize the potential of RGB-D data for fully automatic registration approaches in combination with augmented reality guidance

Late stages of the evolution of A-type stars on the main sequence: comparison between observed chemical abundances and diffusion models for 8 Am stars of the Praesepe cluster

Aims. We aim to provide observational constraints on diffusion models that predict peculiar chemical abundances in the atmospheres of Am stars. We also intend to check if chemical peculiarities and slow rotation can be explained by the presence of a weak magnetic field. Methods. We have obtained high resolution, high signal-to-noise ratio spectra of eight previously-classified Am stars, two normal A-type stars and one Blue Straggler, considered to be members of the Praesepe cluster. For all of these stars we have determined fundamental parameters and photospheric abundances for a large number of chemical elements, with a higher precision than was ever obtained before for this cluster. For seven of these stars we also obtained spectra in circular polarization and applied the LSD technique to constrain the longitudinal magnetic field. Results. No magnetic field was detected in any of the analysed stars. HD 73666, a Blue Straggler previously considered as an Ap (Si) star, turns out to have the abundances of a normal A-type star. Am classification is not confirmed for HD 72942. For HD 73709 we have also calculated synthetic Delta-a photometry that is in good agreement with the observations. There is a generally good agreement between abundance predictions of diffusion models and values that we have obtained for the remaining Am stars. However, the observed Na and S abundances deviate from the predictions by 0.6 dex and >0.25 dex respectively. Li appears to be overabundant in three stars of our sample.Comment: Accepted for publication on A&

Complete experimental toolbox for alignment-free quantum communication

Quantum communication employs the counter-intuitive features of quantum physics to perform tasks that are im- possible in the classical world. It is crucial for testing the foundations of quantum theory and promises to rev- olutionize our information and communication technolo- gies. However, for two or more parties to execute even the simplest quantum transmission, they must establish, and maintain, a shared reference frame. This introduces a considerable overhead in communication resources, par- ticularly if the parties are in motion or rotating relative to each other. We experimentally demonstrate how to circumvent this problem with the efficient transmission of quantum information encoded in rotationally invariant states of single photons. By developing a complete toolbox for the efficient encoding and decoding of quantum infor- mation in such photonic qubits, we demonstrate the fea- sibility of alignment-free quantum key-distribution, and perform a proof-of-principle alignment-free entanglement distribution and violation of a Bell inequality. Our scheme should find applications in fundamental tests of quantum mechanics and satellite-based quantum communication.Comment: Main manuscript: 7 pages, 3 figures; Supplementary Information: 7 pages, 3 figure

Cataclysmic Variables from Sloan Digital Sky Survey V -- the search for period bouncers continues

SDSS-V is carrying out a dedicated survey for white dwarfs, single and in binaries, and we report the analysis of the spectroscopy of cataclysmic variables (CVs) and CV candidates obtained during the final plug plate observations of SDSS. We identify eight new CVs, spectroscopically confirm 53 and refute eleven published CV candidates, and we report 21 new or improved orbital periods. Combined with previously published data, the orbital period distribution of the SDSS-V CVs does not clearly exhibit a period gap. This is consistent with previous findings that spectroscopically identified CVs have a larger proportion of short-period systems compared to samples identified from photometric variability. Remarkably, despite a systematic search, we find very few period bouncers. We estimate the space density of period bouncers to be $\simeq0.2\times10^{-6}\,\mathrm{pc}^{-3}$, i.e. they represent only a few per cent of the total CV population. This suggests that during their final phase of evolution, CVs either destroy the donor, e.g. via a merger, or that they become detached and cease mass transfer.Comment: Submitted to MNRA

Ligand-Directed Chemistry on Glycoside Hydrolases – A Proof of Concept Study

Selective covalent labelling of enzymes using small molecule probes has advanced the scopes of protein profiling. The covalent bond formation to a specific target is the key step of activity-based protein profiling (ABPP), a method which has become an indispensable tool for measuring enzyme activity in complex matrices. With respect to carbohydrate processing enzymes, strategies for ABPP so far involve labelling the active site of the enzyme, which results in permanent loss of activity. Here, we report in a proof of concept study the use of ligand-directed chemistry (LDC) for labelling glycoside hydrolases near – but not in – the active site. During the labelling process, the competitive inhibitor is cleaved from the probe, departs the active site and the enzyme maintains its catalytic activity. To this end, we designed a building block synthetic concept for small molecule probes containing iminosugar-based reversible inhibitors for labelling of two model β-glucosidases. The results indicate that the LDC approach can be adaptable for covalent proximity labelling of glycoside hydrolases.T. M. W. thanks the FWF (Wien, Austria) for financial support (project number P30372-B21). Authors from TU Graz acknowledge support from NAWI Graz.Peer reviewe

Genomics and drug profiling of fatal TCF3-HLF-positive acute lymphoblastic leukemia identifies recurrent mutation patterns and therapeutic options.

TCF3-HLF-positive acute lymphoblastic leukemia (ALL) is currently incurable. Using an integrated approach, we uncovered distinct mutation, gene expression and drug response profiles in TCF3-HLF-positive and treatment-responsive TCF3-PBX1-positive ALL. We identified recurrent intragenic deletions of PAX5 or VPREB1 in constellation with the fusion of TCF3 and HLF. Moreover somatic mutations in the non-translocated allele of TCF3 and a reduction of PAX5 gene dosage in TCF3-HLF ALL suggest cooperation within a restricted genetic context. The enrichment for stem cell and myeloid features in the TCF3-HLF signature may reflect reprogramming by TCF3-HLF of a lymphoid-committed cell of origin toward a hybrid, drug-resistant hematopoietic state. Drug response profiling of matched patient-derived xenografts revealed a distinct profile for TCF3-HLF ALL with resistance to conventional chemotherapeutics but sensitivity to glucocorticoids, anthracyclines and agents in clinical development. Striking on-target sensitivity was achieved with the BCL2-specific inhibitor venetoclax (ABT-199). This integrated approach thus provides alternative treatment options for this deadly disease

Internationalisation in Higher Education as a catalyst to STEAM

Internationalisation efforts in Higher Education are usually led by the institutions' International Offices in partnership with the academic units at various levels, thus providing an ideal opportunity to promote collaboration across colleges, schools and departments, and to bring staff with a broad range of experience and expertise to work together. This chapter discusses two ways in which Higher Education institutions can take advantage of these internationalisation efforts to cultivate and nurture STEAM. First, considering internationalisation of the curriculum (IoC) across disciplines, which entails the incorporation of 'an intercultural dimension into the content of the curriculum as well as the teaching and learning processes and support services of a programme of study' (Leask 2015). Inasmuch as IoC seeks to develop students' international and intercultural perspectives as global professionals and citizens, it requires engagement with the arts, humanities, social sciences and sustainability initiatives across programmes, providing an opportunity to embed STEAM in the curriculum. Further, I argue that there is a parallelism between the national cultures that IoC seeks to draw from and the disciplines themselves, which are also different cultures, 'separate communities of practice with their own organisations, power hierarchies, questions to answer and [sometimes heavily policed] entry boundaries' (Brown and Harris 2014, 115). An interdisciplinary approach, and in particular one that promotes STEAM, should enrich the curriculum and increase its relevance in the same way that an international approach would. And second, through matching an employability and transferable skills training programme across disciplines to the 'internationalisation at home' initiatives that seek to deploy international students and staff as resources in Higher Education institutions (Altbach and Yudkevich 2017). Such a programme would focus on bringing skills traditionally associated with the arts and humanities - such as aesthetic appreciation, critical thinking or communication skills - to students of technology and science, while also bringing skills traditionally associated with science and technology - such as planning and problem solving, numeracy and the use of information technology - to students of arts and humanities, actively taking advantage of the innovative perspectives that international staff and students bring. In sum, the chapter argues that the internationalisation agenda in Higher Education partly inherently overlaps with that of STEAM cultivation, and highlights two practical ways in which curricula can be modified to promote the latter while advancing the former for a more inclusive student experience, enhancing employability skills and promoting the interdisciplinary outlook to the most pressing wicked problems that societies so badly need today