Intermodal coupling as a probe for detecting nanomechanical modes

Nanoelectromechanical systems provide ultrahigh performance in sensing applications. The sensing performance and functionality can be enhanced by utilizing more than one resonance mode of a nanoelectromechanical-systems device. However, it is often challenging to measure mechanical modes at high frequencies or modes that couple weakly to output transducers. In this paper, we propose the use of intermodal coupling as a mechanism to enable the detection of such modes. To implement this method, a probe mode is continuously driven and monitored using a phase-locked loop, while an auxiliary drive signal scans for other modes. Each time the auxiliary drive signal excites the corresponding mode by matching the mechanical frequency, the effective tension within the structure increases, which in turn causes a frequency shift in the probe mode. The location and width of these frequency shifts can be used to determine the frequency and quality factor of mechanical modes indirectly. Intermodal coupling can be used as a tool to obtain the spectrum of a mechanical structure even if some of these modes cannot be detected conventionally

Low-Weight Primes for Lightweight Elliptic Curve Cryptography on 8-bit AVR Processors

Small 8-bit RISC processors and micro-controllers based on the AVR instruction set architecture are widely used in the embedded domain with applications ranging from smartcards over control systems to wireless sensor nodes. Many of these applications require asymmetric encryption or authentication, which has spurred a body of research into implementation aspects of Elliptic Curve Cryptography (ECC) on the AVR platform. In this paper, we study the suitability of a special class of finite fields, the so-called Optimal Prime Fields (OPFs), for a "lightweight" implementation of ECC with a view towards high performance and security. An OPF is a finite field Fp defined by a prime of the form p = u*2^k + v, whereby both u and v are "small" (in relation to 2^k) so that they fit into one or two registers of an AVR processor. OPFs have a low Hamming weight, which allows for a very efficient implementation of the modular reduction since only the non-zero words of p need to be processed. We describe a special variant of Montgomery multiplication for OPFs that does not execute any input-dependent conditional statements (e.g. branch instructions) and is, hence, resistant against certain side-channel attacks. When executed on an Atmel ATmega processor, a multiplication in a 160-bit OPF takes just 3237 cycles, which compares favorably with other implementations of 160-bit modular multiplication on an 8-bit processor. We also describe a performance-optimized and a security-optimized implementation of elliptic curve scalar multiplication over OPFs. The former uses a GLV curve and executes in 4.19M cycles (over a 160-bit OPF), while the latter is based on a Montgomery curve and has an execution time of approximately 5.93M cycles. Both results improve the state-of-the-art in lightweight ECC on 8-bit processors

Sketch-a-Net: A Deep Neural Network that Beats Humans

This Project received support from the European Union’s Horizon 2020 Research and Innovation Programme under Grant Agreement #640891, and the Royal Society and Natural Science Foundation of China (NSFC) Joint Grant #IE141387 and #61511130081. We gratefully acknowledge the support of NVIDIA Corporation for the donation of the GPUs used for this research

Reducing the environmental impact of surgery on a global scale: systematic review and co-prioritization with healthcare workers in 132 countries

Background Healthcare cannot achieve net-zero carbon without addressing operating theatres. The aim of this study was to prioritize feasible interventions to reduce the environmental impact of operating theatres. Methods This study adopted a four-phase Delphi consensus co-prioritization methodology. In phase 1, a systematic review of published interventions and global consultation of perioperative healthcare professionals were used to longlist interventions. In phase 2, iterative thematic analysis consolidated comparable interventions into a shortlist. In phase 3, the shortlist was co-prioritized based on patient and clinician views on acceptability, feasibility, and safety. In phase 4, ranked lists of interventions were presented by their relevance to high-income countries and low–middle-income countries. Results In phase 1, 43 interventions were identified, which had low uptake in practice according to 3042 professionals globally. In phase 2, a shortlist of 15 intervention domains was generated. In phase 3, interventions were deemed acceptable for more than 90 per cent of patients except for reducing general anaesthesia (84 per cent) and re-sterilization of ‘single-use’ consumables (86 per cent). In phase 4, the top three shortlisted interventions for high-income countries were: introducing recycling; reducing use of anaesthetic gases; and appropriate clinical waste processing. In phase 4, the top three shortlisted interventions for low–middle-income countries were: introducing reusable surgical devices; reducing use of consumables; and reducing the use of general anaesthesia. Conclusion This is a step toward environmentally sustainable operating environments with actionable interventions applicable to both high– and low–middle–income countries

An High-Speed ECC-based Wireless Authentication Protocol on an ARM Microprocessor

In this paper, we present the results of our implementation of elliptic curve cryptography (ECC) over the field GF (p) on an 80-MHz, 32-bit ARM microprocessor. We have produced a practical software library which supports variable length implementation of the elliptic curve digital signature algorithm (ECDSA). We implemented the ECDSA and a recently proposed ECC-based wireless authentication protocol using the library. Our timing results show that the 160-bit ECDSA signature generation and verification operations take around 46 ms and 94 ms, respectively. With these timings, the execution of the ECC-based wireless authentication protocol takes around 140 ms on the ARM7TDMI processor, which is a widely used, low-power core processor for wireless applications

High-Speed Implementation of an ECC-based Wireless Authentication Protocol on an

In this paper, we present the results of our implementation of elliptic curve cryptography (ECC) over the field GF(p) onan80-MHz, 32-bit ARM microprocessor. We have produced a practical software library which supports variable length implementation of the elliptic curve digital signature algorithm (ECDSA). We implemented the ECDSA and a recently proposed ECC-based wireless authentication protocol using the library. Our timing results show that the 160-bit ECDSA signature generation and verification operations take around 46 ms and 94 ms, respectively. With these timings, the execution of the ECC-based wireless authentication protocol takes around 140 ms on the ARM7TDMI processor, which is a widely used, low-power core processor for wireless applications.

Jeneralize liken nitidus

Lichen nitidus, a rare condition of unknown etiology, is characterized by minute, flesh colored, shiny papules commonly occurring on the genitali, abdomen, chest and extremities. The trunk of 11 year old male patient, with arms and legs had widespread papules. The lymphohistiocytic infiltration in dermal papilla was observed on histopathologic examination. The lymphohistiocytic infiltration was encirculed by rete ridges. Without any treatment, we have recommended follow-up our patient. © 2010 Düzce Medical Journal