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Multidrug resistance (MDR) transporters such as ATP Binding Cassette (ABC) and Major Facilitator Superfamily (MFS) proteins are important mediators of antifungal drug resistance, particularly with respect to azole class drugs. Consequently, identifying molecules that are not susceptible to this mechanism of resistance is an important goal for new antifungal drug discovery. As part of a project to optimize the antifungal activity of clinically used phenothiazines, we synthesized a fluphenazine derivative (CWHM-974) with 8-fold higher activity againstCandidaspp. compared to the fluphenazine and with activity againstCandidaspp. with reduced fluconazole susceptibility due to increased multidrug resistance transporters. Here, we show that the improvedC. albicansactivity is because fluphenazine induces its own resistance by triggering expression of CDR transporters while CWHM-974 induces expression but does not appear to be a substrate for the transporters or is insensitive to their effects through other mechanisms. We also found that fluphenazine and CWHM-974 are antagonistic with fluconazole inC. albicansbut not inC. glabrata, despite inducingCDR1expression to high levels. Overall, CWHM-974 represents a unique example of a medicinal chemistry-based conversion of chemical scaffold from MDR-sensitive to MDR-resistant and, hence, active against fungi that have developed resistance to clinically used antifungals such as the azoles.

peer-reviewed An active battery management system for lithium ion battery stacks is described, that is robust and scalable. The architecture is based on an isolation unit consisting of a small equal turns ratio high isolation transformer with two diodes. One isolation unit is connected to each series connected cell in the battery stack and enables both accurate cell voltage monitoring and active cell balancing. The output of the isolation unit is completely galvanically isolated and thus suitable for high voltage packs with stringent safety requirements such as automotive and industrial electrical vehicles. Detailed measurements results are presented and a complete prototype for a LiFePO4 16s2p 2-kWh battery module is constructed and its performance measured. ACCEPTED peer-reviewed

Background Addressing recruitment and retention challenges in trials is a key priority for methods research, but navigating the literature is difficult and time-consuming. In 2016, ORRCA ( www.orrca.org.uk ) launched a free, searchable database of recruitment research that has been widely accessed and used to support the update of systematic reviews and the selection of recruitment strategies for clinical trials. ORRCA2 aims to create a similar database to map the growing volume and importance of retention research. Methods Searches of Medline (Ovid), CINAHL, PsycINFO, Scopus, Web of Science Core Collection and the Cochrane Library, restricted to English language and publications up to the end of 2017. Hand searches of key systematic reviews were undertaken and randomised evaluations of recruitment interventions within the ORRCA database on 1 October 2020 were also reviewed for any secondary retention outcomes. Records were screened by title and abstract before obtaining the full text of potentially relevant articles. Studies reporting or evaluating strategies, methods and study designs to improve retention within healthcare research were eligible. Case reports describing retention challenges or successes and studies evaluating participant reported reasons for withdrawal or losses were also included. Studies assessing adherence to treatments, attendance at appointments outside of research and statistical analysis methods for missing data were excluded. Eligible articles were categorised into one of the following evidence types: randomised evaluations, non-randomised evaluations, application of retention strategies without evaluation and observations of factors affecting retention. Articles were also mapped against a retention domain framework. Additional data were extracted on research outcomes, methods and host study context. Results Of the 72,904 abstracts screened, 4,364 full texts were obtained, and 1,167 articles were eligible. Of these, 165 (14%) were randomised evaluations, 99 (8%) non-randomised evaluations, 319 (27%) strategies without evaluation and 584 (50%) observations of factors affecting retention. Eighty-four percent (n = 979) of studies assessed the numbers of participants retained, 27% (n = 317) assessed demographic differences between retained and lost participants, while only 4% (n = 44) assessed the cost of retention strategies. The most frequently reported domains within the 165 studies categorised as ‘randomised evaluations of retention strategies’ were participant monetary incentives (32%), participant reminders and prompts (30%), questionnaire design (30%) and data collection location and method (26%). Conclusion ORRCA2 builds on the success of ORRCA extending the database to organise the growing volume of retention research. Less than 15% of articles were randomised evaluations of retention strategies. Mapping of the literature highlights several areas for future research such as the role of research sites, clinical staff and study design in enhancing retention. Future studies should also include cost–benefit analysis of retention strategies.

peer-reviewed This letter describes an enhancement to a previously reported single-stage transformer-leakage-inductance-based power-factor-corrected isolated power supply. An improved switch timing calculation algorithm is developed to achieve zero current switch on of the active rectifier switches. The algorithm is based on an analytical model of the system relating the gate timing to the input and output voltages and control inputs. Remarkably, a closed-form expression for the switch timing can be derived and used to calculate and apply the timings in real time without the need for high-speed measurements or resonant structures. A prototype 1.25 kW prototype power supply is implemented using the proposed technique and performance measurements presented. ACCEPTED peer-reviewed

Geraldine Cummins and Susanne R. Day’s collaboration on Fox and Geese (1917) throws up several critical questions that reflect an equivocal light on the Abbey Theatre’s relationship with women playwrights in its early years. Why did Cummins and Day submit the play under a male pseudonym when the Abbey Theatre had already successfully produced their play, Broken Faith, in 1913? What were the changes they made to its ending at the behest of St. John Ervine acting on behalf of the Abbey Theatre, and how did those changes secure its production? Why would the play become the final collaboration between these committed suffragists and close friends? While firm answers remain elusive, the experiences of Cummins and Day offer perspectives on whether the Abbey Theatre exerted hegemonic forces over women playwrights as early as its second decade of operation.

Poor retention of participants in randomised trials can lead to missing outcome data which can introduce bias and reduce study power, affecting the generalisability, validity and reliability of results. Many strategies are used to improve retention but few have been formally evaluated.To quantify the effect of strategies to improve retention of participants in randomised trials and to investigate if the effect varied by trial setting.We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Scopus, PsycINFO, CINAHL, Web of Science Core Collection (SCI-expanded, SSCI, CPSI-S, CPCI-SSH and ESCI) either directly with a specified search strategy or indirectly through the ORRCA database. We also searched the SWAT repository to identify ongoing or recently completed retention trials. We did our most recent searches in January 2020.We included eligible randomised or quasi-randomised trials of evaluations of strategies to increase retention that were embedded in 'host' randomised trials from all disease areas and healthcare settings. We excluded studies aiming to increase treatment compliance.We extracted data on: the retention strategy being evaluated; location of study; host trial setting; method of randomisation; numbers and proportions in each intervention and comparator group. We used a risk difference (RD) and 95% confidence interval (CI) to estimate the effectiveness of the strategies to improve retention. We assessed heterogeneity between trials. We applied GRADE to determine the certainty of the evidence within each comparison.We identified 70 eligible papers that reported data from 81 retention trials. We included 69 studies with more than 100,000 participants in the final meta-analyses, of which 67 studies evaluated interventions aimed at trial participants and two evaluated interventions aimed at trial staff involved in retention. All studies were in health care and most aimed to improve postal questionnaire response. Interventions were categorised into broad comparison groups: Data collection; Participants; Sites and site staff; Central study management; and Study design. These intervention groups consisted of 52 comparisons, none of which were supported by high-certainty evidence as determined by GRADE assessment. There were four comparisons presenting moderate-certainty evidence, three supporting retention (self-sampling kits, monetary reward together with reminder or prenotification and giving a pen at recruitment) and one reducing retention (inclusion of a diary with usual follow-up compared to usual follow-up alone). Of the remaining studies, 20 presented GRADE low-certainty evidence and 28 presented very low-certainty evidence. Our findings do provide a priority list for future replication studies, especially with regard to comparisons that currently rely on a single study.Most of the interventions we identified aimed to improve retention in the form of postal questionnaire response. There were few evaluations of ways to improve participants returning to trial sites for trial follow-up. None of the comparisons are supported by high-certainty evidence. Comparisons in the review where the evidence certainty could be improved with the addition of well-done studies should be the focus for future evaluations.

On the 11th of March 2020, the World Health Organisation (WHO) declared a global pandemic due to the SARS-CoV-2 virus, which causes coronavirus disease 2019 (COVID-19). This was one month after Dr. Tedros Adhanom Ghebreyesus, Director-General of the WHO declared that we are also fighting an ‘infodemic’. The WHO has described an infodemic as an “over-abundance of information – some accurate and some not – that makes it hard for people to find trustworthy sources and reliable guidance when they need it”. iHealthFacts.ie is an Irish resource where the public can quickly and easily check the credibility and reliability of health claims circulating on social media. Unreliable claims can lead to poorly informed health choices. iHealthFacts is an initiative that supports the public to think critically about health claims and make well-informed choices. Here, we describe the role iHealthFacts plays in providing reliable information to the public and offer reflections from those involved in launching this initiative during a pandemic.

A simple active battery management system for lithium ion battery stacks is described, that is robust and scalable. The architecture is based on an isolation unit consisting of a small equal turns ratio high isolation transformer with two diodes. One isolation unit is connected to each series connected cell in the battery stack and enables both accurate cell voltage monitoring and active cell balancing. The output of the isolation unit is completely galvanically isolated and thus suitable for high voltage packs with stringent safely requirements such as automotive and industrial electrical vehicles. Detailed measurements results are presented and a complete prototype for a LiFePO4 16s2p 2kWh battery module is constructed and its performance measured.

Use of parallel resonance to notch filter the fundamental ripple frequency on a switching regulator output offers advantages in the combined metric of size and power compared to traditional low-pass solutions. Availability of barium strontium titanate varactors with capacitance of several nanofarads now makes automatic tuning of parallel resonance alignment with the ripple fundamental a feasible alternative. A phase-lock automatic-tuning circuit is demonstrated. The effective use of this technique as the power-supply filter used to power a 16 bit ADC is shown. The suitability of the resulting filter and regulator to full surface mount encapsulation is demonstrated.

Background The Health Research Board-Trials Methodology Research Network (HRB-TMRN) celebrates International Clinical Trials Day with the help of the younger members of our community through the Network’s ‘Schools Teaching Awareness of Randomised Trials (START)’ initiative. START seeks to increase public awareness of randomised trials in Ireland. Launched in 2016, it asks children (8–12 years old) to conduct and report their very own fun randomised trial. The study reported in this paper sought to explore children and teachers perceptions and experiences of the START initiative. Methods We conducted eight, one-to one interviews with teachers and eight focus groups with 61 children who took part in the 2018 START initiative. Interviews and focus groups were recorded and transcribed and the data analysed using template analysis. Results The findings of this study highlight the benefits of participating in START and the areas of the initiative that required further attention. Teachers and children recalled the benefits of experiential learning associated with START and learning by doing encouraged a fun way of engaging with trial processes. By recalling all aspects of planning, conducting and reporting their trial, the children in this study demonstrated their awareness of the trial processes. The teachers suggested that START provides a valuable framework to contribute to key aspects of the primary school curriculum in Ireland. The experiences of these participants also provided recommendation for improving the programme for future START participants. Conclusions Increasing public awareness and understanding of randomised trials can help increase public engagement in trials. By educating children about the importance of trials and supporting them to ‘learn by doing’ by carrying out their own trial, the START initiative can contribute substantially to children’s awareness and understanding of trial processes. Given that children are the public, the patients and the researchers of the future, initiatives such as START deserve attention.

Background: Subcutaneous fat necrosis (SCFN) is a rare form of panniculitis mostly seen in neonates with a history of significant perinatal stress and may be associated with life-threatening hypercalcemia. Clinical Case: An infant boy born by emergent C-section at 39 4/7 weeks to a 32 y/o G2P0 mother due to pre-eclampsia, emerged limp, cyanotic and apneic with heart rate4000 IU/L, n 100 - 250 IU/L), abnormal coagulation panel (PT 75.4 sec, n 9.7 - 12.4 sec; PTT 58.7 sec, n 25 - 37 sec; INR 6.85, n 0.9 - 1.2) and thrombocytopenia (platelet count 90 K/uL, n 150 - 450 K/uL). IV fluids, platelet transfusions and antibiotics were given for presumed sepsis. WBTH was completed on day of life (DOL) 3 and infant was re-warmed overnight. SCFN presented on DOL 4 as erythematous, tender, nodular indurations throughout the skin over the dorsum. Supportive therapy was given: repositioning, morphine for pain during feeding and handling and bacitracin ointment to areas of skin desquamation. Labs were consistent with SCFN. On DOL 18, total serum calcium (TSC) increased to 11.8 mg/dL (n 8.8 - 11.2 mg/dL), intact parathyroid hormone (1 pg/mL, n 14 - 72 pg/mL), PTH related peptide (

Efficiently exploiting renewable, sustainable and green energy resources is one of the most critical challenges facing our world today. For example, as part of this challenge, Germany aims to generate 65% of its electricity from renewable sources by 2020 and Ireland aims to generate 40%. Renewable energy sources, e.g. solar and wind energy, are plentiful and sufficient to power our ever-increasing demand for more devices, technology and transportation. However, the increased demand for electricity at peak times, the increased instantaneous penetration of the grid by energy from non-conventional generation systems (such as wind turbines and solar photovoltaic) and the intermittent and non-dispatchable nature of renewable energy sources are threatening the stability of the electricity grid and limiting the ability of the transmission system operator to respond to sudden changes in generation or demand. This is particularly an issue in isolated grids such as on the island of Ireland, where the failure of a single generator results in the loss of a significant fraction of the overall grid capacity in an instant. However, in mainland Europe, the electricity grid of each nation is interconnected and synchronised, allowing the loss of a single generator in one region to be compensated for by increasing the output of the many other generators on the continent by a small amount. In the future, there will be a need for significant grid-scale storage, load levelling and stabilisation of the grid. Electric vehicles will become more prevalent and the fraction of renewables on the grid will increase significantly. These technologies and the way in which they interact with the grid will greatly affect the stability of the electricity grid. Smart and innovative interaction of these technologies with the grid raises the possibility of optimising the level of energy storage required for stable and reliable grid operation. However, lack of planning in these areas could make future cost-effective, sustainable and reliable energy solutions hard to achieve.

The widespread use of electronic devices increases the need for compact power factor corrected power supplies. This paper describes an isolated power factor corrected power supply that utilizes the leakage inductance of the isolation transformer to provide boost inductor functionality. The bulk capacitor is in the isolated part of the power supply allowing for controlled startup without dedicated surge limiting components. A control method based on switch timing and input/output voltage measurements is developed to jointly achieve voltage regulation and input power factor control. A prototype design is implemented with detailed measurements and waveforms shown to confirm the desired functionality., Comment: This work has been submitted to the IEEE for possible publication. Copyright may be transferred without notice, after which this version may no longer be accessible

peer-reviewed Noseband tightness is difficult to assess in horses participating in equestrian sports such as dressage, show jumping and three-day-eventing. There is growing concern that nosebands are commonly tightened to such an extent as to restrict normal equine behaviour and possibly cause injury. In the absence of a clear agreed definition of noseband tightness, a simple model of the equine nose-noseband interface environment was developed in order to guide further studies in this area. The normal force component of the noseband tensile force was identified as the key contributor to sub-noseband tissue compression. The model was used to inform the design of a digital tightness gauge which could reliably measure the normal force component of the noseband tensile force. A digital tightness gauge was developed to measure this parameter under nosebands fitted to bridled horses. Results are presented for field tests using two prototype designs. Prototype version three was used in field trial 1 (n = 15, frontal nasal plane sub-noseband site). Results of this trial were used to develop an ergonomically designed prototype, version 4, which was tested in a second field trial (n = 12, frontal nasal plane and lateral sub-noseband site). Nosebands were set to three tightness settings in each trial as judged by a single rater using an International Society for Equitation Science (ISES) taper gauge. Normal forces in the range 7-95 N were recorded at the frontal nasal plane while a lower range 1-28 N was found at the lateral site for the taper gauge range used in the trials. The digital tightness gauge was found to be simple to use, reliable, and safe and its use did not agitate the animals in any discernable way. A simple six point tightness scale is suggested to aid regulation implementation and the control of noseband tightness using normal force measurement as the objective tightness discriminant. PUBLISHED peer-reviewed

This paper describes the process we undertook to address a significant technical communication issue embedded within traditional information-distribution procedures in the U.S. National Park Service: The bureau's nationally circulated brochures, as print artifacts, are inaccessible to people who are blind, visually impaired and print dyslexic and also not optimized for people who prefer audio communication. This report includes findings from the second year of a three-year project, funded by a grant from the National Park Service. Our first year on this project was spent getting to know the frameworks and foundations of the 342 brochures currently circulating in the country, through a deep reading of samples and a larger content analysis of the brochure structures and content genres. The second year of this project, which is the focus of this paper and poster presentation at SIGDOC 2016, revolves around the design-based research prototyping experiments we conducted as a way to create and refine a web tool to support and produce audio description, particularly in relation to the remediation of NPS brochures to audio-based mobile apps. This process led to prototyping experiments within the NPS that revealed a significant gap between practitioner knowledge and best practices. Those best practices also were found to be lacking in many areas, such as guidance for the practitioners to audio describe a NPS staple, the site map. While audio description, like open/closed captioning, might be considered a relatively straightforward process to those uninitiated in the activity, these practitioner experiments revealed many of the nuances and complexities of audio description that make it a difficult translation exercise. They also led to the generation of important scholarly research questions, such as "In what ways could one audio describe a map?"

This paper presents a high accuracy and high bandwidth current sense circuit for digitally controlled DC-DC buck converters. The circuit uses lossless inductor DCR current sensing and a sigma delta modulator ADC to sense the average current in the inductor to high accuracy. These accurate but low bandwidth measurements are unsuitable for use in feedback control loops as their acquisition delay would limit the achievable loop bandwidth. To solve this issue a Kalman Filter estimates the inductor current at the switching frequency of the converter. The output of the estimator is shown through experimental results to achieve 0.3A static current accuracy when used in a buck converter switching at 1MHz and using a power efficient inductor with a DCR of only 165µOhms.

Previous research indicates that bar workers report high levels of alcohol consumption, but the bar work experience itself has been little studied as a means to understand health threats associated with this job role. The subjective experience and meaning of bar work was explored in this study by interviewing current and ex-bar workers from a district in an Irish city that had a high density of bars and busy tourism industry. A total of 12 participants took part in focus groups (FGs) and seven in individual interviews. Four themes were identified in a thematic analysis. The central depiction of bar work was of an initial immersion in an intensive lifestyle characterised by heavy drinking, with subsequent distancing from the extremes of the lifestyle. The participants affiliated strongly with the bar work occupational identity, which included alcohol use in group scenarios for drinking during work, after work and on time off. The bar work lifestyle was most intense in the 'superpub' environment, characterised by permissive staff drinking norms and reported stress. Although an important identity, bar work was ultimately a transient role. The findings are considered in relation to research on occupation-specific stress and alcohol use, social identity and developmental needs in young adulthood.

The M-algorithm is a reduced complexity, breadth-first, trellis search alternative to the Viterbi algorithm. It is particularly useful when the number of trellis states is so large as to render Viterbi detection impractical. When dealing with complex or long target responses, values of M ges 16 may be required in order to approach MLD performance. Performing path selection for M ges 16 using previously reported methods can be computationally complex and prohibitive to practical hardware implementation. This paper details reduced complexity path selection networks for use with large values of M. A strategy for the construction of reduced complexity networks is presented and can be used to create networks for a variety of values of M and for other applications where M-algorithm detection can be employed. The use of these networks will allow for practical realisable hardware implementations of M-algorithm detectors for M ges 16.

We describe a low-complexity noniterative detector for magnetic and optical multitrack high-density data storage. The detector is based on the M-algorithm architecture. It performs limited breadth-first detection on the equivalent one-dimensional (1-D) channel obtained by column-by-column helical unwinding of the two-dimensional (2-D) channel. The detection performance is optimized by the use of a specific 2-D minimum-phase factorization of the channel impulse response by the equalizer. An optimized path selection scheme maintains the complexity close to practical 1-D Viterbi. This scheme is based on an approximate path metric parallel sort network, taking advantage of the metrics' residual ordering from previous M-algorithm iterations. Such an architecture approaches maximum-likelihood performance on a high areal density uncoded channel for a practical number of retained paths M and bit error rate (BER) below 10-4. The performance of the system is evaluated when the channel is encoded with multi-parity check (MPC) block inner code and an outer interleaved Reed-Solomon code. The inner code enhances the minimum error distance of the equalized channel and reduces the correct path losses of the M-algorithm path buffer. The decoding is performed noniteratively. Here, we compare the performance of the system to the soft iterative joint decoding of the read channels for data pages encoded with low-density parity check (LDPC) codes with comparable rates and block length. We provide an approximation of the 2-D channel capacity to further assess the performance of the system

Using a multitrack format in both optical and magnetic data storage applications yields important improvements in system performance, including higher data density and higher data transfer rates. However, the full advantage in data density can be achieved only through the use of joint equalization and joint detection. This paper addresses the complexity of implementing these functions and proposes a transform domain equalization architecture and a reduced-complexity detection method based on a breadth first search of a one-dimensional time-varying representation of a two-dimensional target response. With this method, the complexity of joint equalization and joint detection is not unreasonably greater than that of existing single-track systems and should be feasible for implementation with emerging integrated circuit technologies.

In this paper, a modified equalization target is proposed for the high density magnetic recording channel. This target is a closer match to the channel than the EEPR4 response and hence has better detection performance. Based on the dominant error events for this target, a parity-based coding scheme is also proposed to achieve a coding gain with the modified target. The use of the parity code detects the occurrence of the dominant error events while achieving a high code rate. The detection system consists of a Viterbi detector matched to the channel response and a post processor to handle the code constraints. This system is shown to perform well compared to other proposed detection systems through analysis and simulation on a Lorentzian based channel model.

Data from digital data storage media employing a multitrack storage format can be efficiently detected with reduced complexity by using a breadth-first search algorithm on a one-dimensional time-varying trellis representation of the multitrack channel response. In this letter, we analyze the resulting performance. We propose a two-dimensional minimum phase detector target response and verify its performance through bit-error-rate simulations.

This paper presents an application of Matched Spectral Null (MSN) coding to the magnetic recording channel that allows increased recording densities. A PR1 1+D partial response channel is used in combination with a DC and Nyquist free code to provide coding gain. A Viterbi detector based on the combined trellis of the code and channel is used for decoding. Using this scheme, increased user linear recording density over current PR4 systems can be obtained.

A new equalization target for the high-density magnetic recording channel is proposed based on the PR1 partial response combined with decision feedback. A detector for the new target is developed and shown to allow practical implementation. The performance of the detector is assessed through analysis and simulation. It is shown that the detector is suitable for channel recording densities of 3 bits per PW/sub 50/.

A low power integrated transceiver incorporating a full Industrial Scientific Medical (ISM) band low IF transmitter and receiver with an application specific RISC processor design is described. The RISC processor contains hardware acceleration blocks, including parallel-to-serial, timers, 8B10B endec and an AES cryptographic accelerator. Application specific microcode allows the device to be tailored for different applications through a single custom mask. The design is fabricated on 0.18um CMOS. Measurements and results from prototype silicon are presented.

The paper introduces the concept of two-dimensional optical storage (TwoDOS). In this concept, bits are written in a broad spiral consisting of a number of bit-rows stacked together in a hexagonal packing. Bits with a value '1' are represented physically as circular pit-holes on the disc, while bits with a value '0' are characterized by the absence of such a pit-hole. A scalar diffraction model is used to calculate the signal levels for various diameters of the pits. A stripe-wise Viterbi detector is proposed to perform 2D bit-detection with a limited state complexity of the trellis. Simulation results are shown for various diameters of the pits. A 2D modulation code is applied to eliminate patterns that yield a high probability of erroneous detection.

A new form of coding is described which allows certain minimum distance error events on the PR4 partial response channel to be eliminated. When used on the magnetic recording channel, this method provides an increase in effective SNR of 1.25 dB at the recording densities of interest. The minimum distance events eliminated are those which are most affected by noise correlation. Parity codes are shown to-achieve the desired effect but with poor run length properties. Codes with a zero running digital sum modulo 3 are shown to achieve the desired gain but with better run length properties. The performance gains are evaluated by analysis and simulations, and the complexity of implementation is compared to alternative methods.

New efficient structures using the one-hot residue number system (OHRNS) are presented. Normally the RNS uses a binary representation for the residues, though recently there has been renewed interest in the OHRNS, which uses a simple, but novel representation for the residues. The basic component of the OHRNS is the barrel shifter, making the OHRNS suitable for very high speed applications. The first of the new structures presented reduces the power dissipation in OHRNS adder trees. A modification to the normal barrel shifter is proposed, which reduces the power dissipated by as much as 30%. This improvement is obtained through the use of the modified barrel shifter and the appropriate connection of active-low and active-high stages. This overall power reduction offers the possibility of using the OHRNS in place of a typical full adder based tree in high speed DSP applications. A new storage register for one-hot representations is detailed, which overcomes the problem of having to use a large number of registers. A new architecture is presented for fast OHRNS sign detection. Sign detection is complex and slow to perform in the RNS. A mixed radix conversion (MRC) is typically used for sign detection in the OHRNS. The new sign detection architecture is based on a new property of the Chinese Remainder Theorem (CRT) and is significantly faster than the MRC approach for large moduli sets. Simulation results using SPICE are detailed for the new structures.

This paper presents a simple RISC processor that allows the user to add customized instructions to accelerate key algorithms. The new instructions are added by modifying the HDL description of the processor. The processor can be programmed and the added instructions can be accessed through a high level language. The use of such features is demonstrated through examples of Reed Solomon decoding and the Log-MAP algorithm used in decoding Turbo codes. The examples show that considerable improvements in performance can be achieved by adding specific specialized instructions. Such features should be of use in future system on a chip applications that will require such algorithms to be implemented efficiently. (22 pages)