Efficient Digital Signal Processing Techniques and Architectures for On-Board Processors

In this paper, we present a number of algorithmic and architectural DSP solutions to be incorporated in digital OBPs for communication satellites to boost the system performance primarily in terms of reducing their power consumption. More specifically this article addresses (1) Infinite impulse response (IIR) implementation of digital filters, (2) Efficiency savings in channeliser FFT twiddle storage and multiplications and their reconfigurable implementation (3) Companding of interconnect data, and (4) Critically sampled/reduced over-sampling channelisation. The applicability and efficiency of these approaches were evaluated in detail during our European Space Agency (ESA) funded research project entitled "Efficient Techniques for On-Board Processing”, undertaken by Airbus Defence and Space and the Applied DSP and VLSI Research Group at the University of Westminster. The results demonstrated noteworthy improvements both in terms of power dissipation, and furthermore in the reduction of circuit complexity for future digital OBPs, which will be shown at the summary of results section

On board Processor and Processing Strategies for Next Generation Reconfigurable Satellite Payloads

Today, the increasing demand in higher data rates necessitates new methods as well as higher flexibility for satellite telecommunication payloads in order to address a variety of applications and customers. This paper presents one of these processing strategies that is applicable to today’s processing satellite payloads aiming to meet those demands. For this purpose, a two-tier filter bank is designed as part of a digital onboard processor, which first divides the spectrum at the output of the ADC into a number of sub-bands extracting all the stacked channels in the digital domain. Following the analysis section of the first tier of operations, the extracted channels go under a secondary channelisation process to obtain much finer granularity of 31.25 kHz or 50 kHz depending on the communication standard used for data transmission. The implementation of the channeliser was delivered on a bit-true simulation model and the input and the output of the channelisers were compared and evaluated both in the time and frequency domains

The Design of Low Complexity Low Power Pipelined Short Length Winograd Fourier Transforms

In this paper a novel pipelining approach applicable to Winograd Fourier transforms is presented. The novel approach makes use of reconfigurable multiplier blocks to implement the real multipliers required for the transform as well as sharing the hardware resources among additions. The additions are realized using modified forms of butterfly circuits. The novel approach is tested on a 5-point Winograd Fourier transform and the circuit area and power dissipation of the design are estimated using an in-house power estimation tool and compared to the state-of-the- art approaches

Facial nerve dehiscence and cholesteatoma: a comparison between decades

OBJECTIVES: To evaluate the incidence of facial canal dehiscence (FCD) and other intraoperative findings over the last 20 years as well as correlation with the Japanese Otological Society/European Academy of Otology and Neurotology classification in patients with cholesteatoma. MATERIALS and METHODS: A total of 469 patients operated from 1998 to 2018 were selected and divided into 2 groups of 10 years each. RESULTS: Dehiscence was significantly higher in patients with a history of pathology longer than 5 years (22.7%). Higher values were observed in revision surgery, 44.4% in the first period and 41.7% in the second. The tympanic segment was the one most frequently involved, affecting 92% of patients in the first period and 97% of patients in the second. Dehiscence occurred significantly more often in patients with a semicircular canal fistula, 14.8% in the first decade and 8.8% in the second. The incidence of FCD was significantly higher in patients with primary cholesteatoma (especially in those with combined pars tensa-flaccida) than in those with a secondary acquired one, 31.5% vs 7.4% in the first period, 21.1% vs 7.4% in the second, and in those with a stage III disease, 42% in the first period, 33.3% in the second. CONCLUSION: Patients with a shorter history of cholesteatoma as well as those not previously operated had a lower incidence of FCD. The tym-panic tract of the facial nerve remains the most frequent site of dehiscence, while the association between dehiscence and fistula of the semicircular canal remains strong. Patients with combined pars tensa-pars flaccida and stage III cholesteatoma have a higher incidence of FCD

Iloprost in Acute Post-kidney Transplant Atheroembolism: A Case Report of Two Successful Treatments

Cholesterol embolization (CE) is a rare and alarming post-transplant complication, responsible for primary non-function (PNF) or delayed graft function (DGF). Its incidence is expected to rise due to increasingly old donors and recipients and the extended criteria for donation. Therapy with statins and steroids has not been shown to be effective, while agonism of prostaglandin I2 has been reported to be useful in systemic CE. We report two cases of acute post-transplant CE in which intravenous iloprost (0.05 mg/kg/day) was added to standard statin and steroid therapy. In the first instance, CE was due to embolization from the kidney artery resulting in embolization of the small vessels; after a long DGF and 15 days of iloprost therapy, renal function recovered. The second instance is a case of embolization from the iliac artery of the recipient, where CE manifested as a partial renal infarction. After 5 days of iloprost administration, creatinine levels improved. Iloprost acts on vasodilation and on different inflammatory pathways, improving the anti-inflammatory profile. Post-transplant CE is difficult to diagnose and, if not treated, can lead to loss of function. Iloprost added to standard therapy could be beneficial in accelerating renal function recovery immediately after transplant

Immunotherapy in the Treatment of Metastatic Melanoma: Current Knowledge and Future Directions

Melanoma is one of the most immunologic malignancies based on its higher prevalence in immune-compromised patients, the evidence of brisk lymphocytic infiltrates in both primary tumors and metastases, the documented recognition of melanoma antigens by tumor-infiltrating T lymphocytes and, most important, evidence that melanoma responds to immunotherapy. The use of immunotherapy in the treatment of metastatic melanoma is a relatively late discovery for this malignancy. Recent studies have shown a significantly higher success rate with combination of immunotherapy and chemotherapy, radiotherapy, or targeted molecular therapy. Immunotherapy is associated to a panel of dysimmune toxicities called immune-related adverse events that can affect one or more organs and may limit its use. Future directions in the treatment of metastatic melanoma include immunotherapy with anti-PD1 antibodies or targeted therapy with BRAF and MEK inhibitors

Mid-regional pro-adrenomedullin as a supplementary tool to clinical parameters in cases of suspicion of infection in the emergency department

Introduction: Mid-regional proadrenomedullin (MR-proADM), a novel biomarker, has recently gained interest particularly with regards to its potential in assisting clinicians\u2019 decision making in patients with suspicion of infection in the emergency department (ED). A group of international experts, with research and experience in MR-proADM applications, produced this review based on their own experience and the currently available literature. Areas covered: The review provides evidence related to MR-proADM as a triaging tool in avoiding unnecessary admissions to hospital and/or inadequate discharge, and identifying patients most at risk of deterioration. It also covers the use of MR-proADM in the context of COVID-19. Moreover, the authors provide a proposal on how to incorporate MR-proADM into patients\u2019 clinical pathways in an ED setting. Expert opinion: The data we have so far on the application of MR-proADM in the ED is promising. Incorporating it into clinical scoring systems may aid the clinician\u2019s decision making and recognizing the \u2018ill looking well\u2019 and the \u2018well looking ill\u2019 sooner. However there are still many gaps in our knowledge especially during the ongoing COVID-19 waves. There is also a need for cost-effectiveness analysis studies especially in the era of increasing cost pressures on health systems globally

Wheat sprout extract induces changes on 20S proteasomes functionality.

Wheat sprouts contain a very high level of organic phosphates and a powerful cocktail of different molecules such as enzymes, reducing glycosides and polyphenols. The antioxidant properties of wheat sprouts have been widely documented and it has been shown that they are able to protect DNA against free-radicals mediated oxidative damage. Furthermore, we have recently reported on the effects of several polyphenols on 20S proteasomes, underlying the dual role of epigallocatechin-3-gallate as an antioxidant and a proteasome effector in cancer cells. The aim of this study was to investigate the effects of wheat sprout extracts on 20S proteasome functionality. Wheat sprout extracts have been analysed and characterized for their polyphenolic content using the Folin-Ciocalteau reagent and RP-HPLC technique. Comparing our data with a polyphenol standard mixture we identified five different polyphenols: gallic acid, epigallocatechin-3-gallate, epigallocatechin, epicatechin and catechin. The treatment of isolated 20S proteasomes with the extract induced a gradual inhibition of all the tested components, ChT-L, T-L, PGPH and BrAAP, in both the complexes. At low extract concentration a slight activation of the enzyme was evident only for the BrAAP component of the constitutive enzyme and the ChT-L activity of the immunoproteasome. b-casein degradation rate decreased, particularly with the immunoproteasome. Human Colon adenocarcinoma (Caco) cells, stimulated with 12-O-tetradecanoylphorbol-13-acetate, showed activation of the 20S proteasome activities at short incubation times and an increase in intracellular oxidative proteins. Cells treatment with wheat sprout extract led to proteasome inhibition in unstimulated cells and attenuated the effects mediated by TPA. Finally, exposure to the extract affected the expression levels of pro-apoptotic proteins

The Challenges of Diagnosis and Treatment of Arrhythmogenic Cardiomyopathy: Are We there yet?

Background: we sought to review the evolution in the diagnosis and treatment of Arrhythmogenic Cardiomyopathy (ACM), a clinically multifaceted entity beyond the observation of ventricular arrhythmias, and the outcome of therapies aiming at sudden death prevention in a single center experience. Methods: retrospective analysis of the data of consecutive patients with an implanted cardioverter-defibrillator (ICD) and a confirmed diagnosis of ACM according to the proposed Padua Criteria, who were referred to our center from January 1992 to October 2021. Results: we enrolled 72 patients (66% males, mean age at implant 46 ± 16 years), 63.9% implanted for primary prevention. At the time of ICD implant, 29 (40.3%) patients had a right ventricular involvement, 24 (33.3%) had a dominant LV involvement and 19 (26.4%) had a biventricular involvement. After a median follow-up of 6,1 years [IQR: 2.5–9.9], 34 patients (47.2%) had 919 sustained episodes of ventricular arrhythmias (VA). 27 patients (37.5%) had 314 episodes of life-threatening arrhythmias (LT-VA), defined as sustained ventricular tachycardia ≥200 beats/min. Considering only the patients with an ICD capable of delivering ATP, 80.4% of VA and 65% of LT-VA were successfully terminated with ATP. 16 (22.2%) patients had an inappropriate ICD activation, mostly caused by atrial fibrillation, while in 9 patients (12.5%) there was a complication needing reintervention (in 3 cases there was a loss of ventricular sensing dictating lead revision). During the follow-up 11 (15.3%) patients died, most of them due to heart failure, and 8 (11.1%) underwent heart transplantation. Conclusions: ACM is increasingly diagnosed owing to heightened suspicion at ECG examination and to improved imaging technology and availability, though the diagnostic workflow is particularly challenging in the earliest disease stages. ICD therapy is the cornerstone of sudden death prevention, albeit its efficacy is not based on controlled studies, and VT ablation/medical therapy are complementary to this strategy. The high burden of ATP-terminated VA makes shock-only devices debatable. The progressive nature of ACM leads to severe biventricular enlargement and refractory heart failure, which pose significant treatment issues when a predominant RV dysfunction occurs owing to the reduced possibility for mechanical circulatory assistance