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Background This study was an open-label, 2-arms, monocentric, randomized clinical trial comparing Xonrid®, a topical medical device, versus standard of care (SOC) in preventing and treating acute radiation dermatitis (ARD) in Head and Neck Cancer (HNC) and Breast Cancer (BC) patients undergoing radiotherapy (RT). Methods Eligible HNC and BC patients were randomized 1:1 to receive Xonrid® + SOC or SOC during RT. Patients were instructed to apply Xonrid® on the irradiated area three times daily, starting on the first day of RT and until 2 weeks after RT completion or until the development of grade ≥ 3 skin toxicity. The primary endpoint was to evaluate the proportion of patients who developed an ARD grade Results Eighty patients (40 for each cancer site) were enrolled between June 2017 and July 2018. Groups were well balanced for population characteristics. All BC patients underwent 3-Dimensional Conformal RT (3D-CRT) whereas HNC patients underwent Volumetric-Modulated Arc Therapy (VMAT). At week 5 the proportion of BC patients who did not exhibit G2 ARD was higher in Xonrid® + SOC group (p = 0.091). In the same group the onset time of G2 ARD was significantly longer than in SOC-alone group (p Conclusion Despite the failure to achieve the primary endpoint, this study suggests that Xonrid® may represent a valid medical device in the prevention and treatment of ARD at least in BC patients, delaying time to develop skin toxicity and reducing the proportion of patients who experienced G2 ARD during RT treatment and 2 weeks later. Trial registration The study was approved by the Ethical Committee of Fondazione IRCCS Istituto Nazionale dei Tumori di Milano (INT 52/14 - NCT02261181). Registered on ClinicalTrial.gov on 21st August 2017.

Introduction: Stereotactic ablative radiotherapy (SABR) has been shown to increase survival in oligometastatic disease, but local control of colorectal metastases remains poor. We aimed to identify potential predictive factors of SBRT response through a multicenter large retrospective database and to investigate the progression to the polymetastatic disease (PMD). Material and methods: The study involved 23 centers, and was approved by the Ethical Committee (Prot. Negrar 2019-ZT). 1033 lung metastases were reported. Clinical and biological parameters were evaluated as predictive for freedom from local progression-free survival (FLP). Secondary end-point was the time to the polymetastatic conversion (tPMC). Results: Two-year FLP was 75.4%. Two-year FLP for lesions treated with a BED < 00 Gy, 100–124 Gy, and ≥125 Gy was 76.1%, 70.6%, and 94% (p = 0.000). Two-year FLP for lesion measuring ≤10 mm, 10–20 mm, and >20 mm was 79.7%, 77.1%, and 66.6% (p = 0.027). At the multivariate analysis a BED ≥125 Gy significantly reduced the risk of local progression (HR 0.24, 95%CI 0.11–0.51; p = 0.000). Median tPMC was 26.8 months. Lesions treated with BED ≥125 Gy reported a significantly longer tPMC as compared to lower BED. The median tPMC for patients treated to 1, 2–3 or 4–5 simultaneous oligometastases was 28.5, 25.4, and 9.8 months (p = 0.035). Conclusion: The present is the largest series of lung colorectal metastases treated with SABR. The results support the use of SBRT in lung oligometastatic colorectal cancer patients as it might delay the transition to PMD or offer relatively long disease-free period in selected cases. Predictive factors were identified for treatment personalization.

Austropuccinia psidii is the causal agent of myrtle rust, a fungal disease that infects over 480 species in the Myrtaceae. A. psidii is a biotrophic pathogen that reproduces sexually and asexually. Sexual reproduction has been previously shown on Syzygium jambos and little is known about its reproductive biology on other hosts or whether populations that were formerly structured by host range can outcross on universally susceptible hosts. We investigated if mating genes in three genomes of A. psidii were under selection as a proxy for whether different strains can reproduce sexually on a shared host. We examined three homologs of the STE3.2 gene, sequences of which were near-identical in the three genomes, and the homeodomain locus, which contained two alleles of two homeodomain genes in each genome. A. psidii likely uses tetrapolar mating. Pheromone/receptor loci were distal to homeodomain loci, and based on haplotypes of a phased assembly, mate compatibility is regulated by multiallelic HD genes and biallelic STE3.2 genes; the third homolog of STE3.2 (STE3.2-1) was present in both haplotypes, and our study supports hypotheses this gene does not regulate mate recognition. Populations of A. psidii formerly structured by host range could potentially outcross on universal hosts based on their related mating genes, however this hypothesis should remain theoretical given the implications for biosecurity. Additionally, we searched for core meiotic genes in genomes of A. psidii, four species of Puccinia, and Sphaerophragmium acaciae through comparative genomics based on 136 meiosis-related orthologous genes modeled from Mycosarcoma maydis. Meiotic genes are conserved in rust fungi at family rank. We analyzed the expression of two meiotic and four mitotic genes of A. psidii on E. grandis over a 28-day time course to validate that identified meiotic genes were upregulated in teliospores. Three mitotic genes were significantly downregulated in samples collected 28 days after inoculation (DAI) compared to 14 DAI. Expression of meiotic genes was significantly up-regulated in samples collected 28 DAI compared to 14 DAI, indicating a temporal switch from production of uredinia (mitotic stage) to telia in the life cycle, which we hypothesize may be in response to leaf ageing.

Xerostomia, the subjective complaint of dry mouth, is caused by therapeutic interventions or diseases. Nowadays, radiotherapy (RT) in patients with head and neck cancer (HNC) stands out as one of the most important causes of xerostomia. Currently available therapies for the treatment of xerostomia are still less than optimal and xerostomia still represents an unmet clinical need. In this article, we present the results of a prospective clinical study with a new product, AqualiefTM, in patients treated with curative RT with or without chemotherapy for HNC. AqualiefTM is based on two main ingredients, carnosine and karkadé, which have acid buffering and antioxidant properties. The study was performed on 30 patients, with 4 of the patients being lost during the study period. Each patient received randomly one of the two treatments, AqualiefTM or placebo, for 8 days. After a 10-day wash-out period, each patient received the other treatment for a further 8 days. The results show that AqualiefTM stimulated salivation in these patients and reduced the pH drop that was observed in an equivalent placebo-treated population of patients. Moreover, no serious, treatment-related adverse events were observed. AqualiefTM has shown positive results, although with limitations due to unsuccessful trial accrual. Therefore, it may be further investigated as a tool for the treatment of RT-related xerostomia.

PURPOSE/OBJECTIVE(S): stereotactic ablative radiotherapy (SABR) has been shown to increase survival rates in oligometastatic disease (OMD), but local control of colorectal metastases still remains poor. We aimed to identify potential predictive factors of SBRT response through a multicenter large retrospective database and to investigate how lung SBRT can impact on the progression to the polymetastatic disease (PMD). MATERIALS/METHODS: the study involved 22 centers, and was approved by the Ethical Committee (Prot. Negrar 2019-ZT). 1023 lung metastases treated with SBRT in 622 patients were reported. The median BED was 105 Gy10. Lesion diameter GTV, PTV volume, dose, fractionations, and site of primary tumor were evaluated as potential predictive marker for SBRT response for the primary end-point local progression-free survival (LPFS). EGFR, KRAS, NRAS, BRAF, and MSI were also evaluated. Secondary end-point was the time to the polymetastatic conversion (ttPMC). RESULTS: the median follow-up was 26 months (range 3-117 months). The median lesion diameter was 13 mm (range 4-58 mm). The 2- and 3-year LPFS were 75.6% and 71%, respectively. At the univariate analysis, BED ≥125Gy10 was associated with improved LPFS (2-year: 94.1% versus 72.6%; P = < 0.0001), single fraction SBRT correlated with better LPFS in the overall population (2-year: 80.6% versus 73.7%; P = 0.03), but no significant difference was observed when considering the population treated with BED > 100 Gy10. Lesion diameter ≤19 mm correlated with improved LPFS (2-year 80% versus 60%; P = < 0.0001). The median ttPMC was 26 months, and the 2-year ttPMC was 54.5%. The median PFS was 11.3 months. After SABR, 36% patients had polymetastatic relapse, 39.5% patients had an oligometastatic relapse, and 24.5% patients had no further relapse. CONCLUSION: the present is the largest series of lung colorectal metastases treated with SABR. The results support the use of SBRT in lung oligometastatic colorectal cancer patients as it might delay the transition to PMD or offer relatively long disease-free period in selected cases. Several biological and clinical predictive factors were identified to assure the highest local control, on the basis of which a decisional algorithm will be derived.

Intensive Rehabilitation Centres, known in Italy as "code 56", admit patients who need to recover from an acute episode. Different Rehabilitation Impact Indices have been proposed as composite rehabilitation outcomes measuring the rate of improvement due to a rehabilitation program. The most widely employed measure the performance of Activities of daily living in rehabilitation is the modified Barthel Index. The Barthel Index-based Rehabilitation Impact Indices are the Rehabilitation Effectiveness and the Rehabilitation Efficiency.The aim of our study was to evaluate the trade-off between Rehabilitation Effectiveness tayand Rehabilitation Efficiency with respect to the Barthel Index admission score and the Length Of Stay, and their ideal ranges that optimized both indices.We retrospectively evaluated data of all patients admitted to intensive rehabilitation unit of the Scientific Institute for Research and Healthcare San Raffaele Pisana of Rome, from January 2006 to March 2018. The primary outcome measures of our study were patient's Rehabilitation Effectiveness and Rehabilitation Efficiency during the hospital stay.A database of 3,466 patients was analysed and the Rehabilitation Effectiveness and Rehabilitation Efficiency indexes were calculated. We calculated the median rank ratio of the Rehabilitation Effectiveness to the Rehabilitation Efficiency against Barthel Index scores. We calculated the median rank ratio of the Rehabilitation Effectiveness to Rehabilitation Efficiency against Barthel Index scores and days of stay. The median rank ratio of the Rehabilitation Effectiveness to the Rehabilitation Efficiency value were 1 in the range of Barthel Index scores from 32 to 42. The median rank ratio of the Rehabilitation Effectiveness to Rehabilitation Efficiency value were 1 for a Length of Stay corresponding to 33 days.In our study we calculated the Trade-offs between Rehabilitation Effectiveness and Rehabilitation Efficiency with respect to admission Barthel Index Score and Length Of Stay in a population of 3,466 patients affected by orthopedic (1,707) and neurological (1,759) diseases. Every member of the healthcare team should be aware of such trade-offs when they make decisions about rehabilitation services.

Local recurrences after breast conserving treatment are mainly close to the original tumor site, and as such shorter fractionation strategies focused on and nearest mammary gland, i.e. accelerated partial breast irradiation (APBI), have been developed. Stereotactic APBI has been attempted, although there is little experience using CyberKnife (CK) for early breast cancer. This pilot study was designed to assess the feasibility of CK-APBI on 20 evaluable patients of 29 eligible, followed for 2 years. The primary endpoint was acute/sub-acute toxicity; secondary endpoints were late toxicity and the cosmetic result. Mean pathological tumor size was 10.5 mm (±4.3, range 3–18), 8 of these patients were classified as LumA-like, 11 as LumB-like, and 1 as LumB-HER2-enriched. Using CK-APBI with Iris, the treatment time was approximately 60 min (range~ 35 to ~ 120). All patients received 30 Gy in five fractions delivered to the PTV. The median number of beams was 180 (IQR 107–213; range:56–325) with a median PTV isodose prescription of 86.0% (IQR 85.0–88.5; range:82–94). The median PTV was 88.1 cm3 (IQR 63.8–108.6; range:32.3–238.8). The median breast V100 and V50 was 0.6 (IQR 0.1–1.5; range:0–13) and 18.6 (IQR 13.1–21.7; range:7.5–37), respectively. The median PTV minimum dose was 26.2 Gy (IQR 24.7–27.6; range 22.3–29.3). Mild side effects were recorded during the period of observation. Cosmetic evaluations were performed by three observers from the start of radiotherapy up to 2 years. Patients’ evaluation progressively increase from 60% to 85% of excellent rating; this trend was similar to that of external observer. These preliminary results showed the safe feasibility of CK-APBI in early breast cancer, with mild acute and late toxicity and very good cosmetic results. The present study is registered at Clinicaltrial.gov ( NCT02896322 ). Retrospectively egistered August 4, 2016.

The incidence of periprosthetic femoral fractures is increasing due to the growing number of THA all over the world and the older age of the population. This article is a review of the literature and an analysis of our cases; the different surgical treatments were described and evaluated. Attention was paid to the border between synthesis and revision.

Purpose To evaluate the dosimetric coverage of axillary levels I, II, and III obtained with standard whole breast irradiation in 1 to 2 positive sentinel lymph nodes (SLNs) patients not submitted to axillary lymph nodes dissection (ALND), and to compare the lymph nodes areas coverage obtained with 3D conformal radiation therapy, intensity-modulated radiotherapy (IMRT), and volumetric modulated arc therapy (VMAT). Methods Patients with 1 to 2 positive SLNs undergoing breast-conserving therapy, without ALND, were included in the analysis. For each patient, 3 treatment plans were performed: a 3D conventional tangential plan, a static IMRT plan, and a volumetric IMRT, designed to encompass the entire breast parenchyma. The volumes of axillary levels I, II, and III receiving 90% and 95% (V90, V95) of the whole breast prescribed dose were evaluated. Dose-volume histograms were compared by means of the Friedman test. Results Ten patients were enrolled. All defined breast volumes received >95% of the prescribed dose with the 3 techniques. Median V95 for axillary level I was 26.4% (range 4.7%-61.3%) for 3D plans, 8.6% (range 0.64%-19.1%) for static IMRT plans, and 2.6% (range 0.4%-4.7%) for volumetric IMRT plans (pConclusions Results of our analysis showed that standard 3D tangential whole breast irradiation failed to deliver a therapeutic dose to axillary levels I and II. The coverage was even lower using static and volumetric IMRT techniques.

Purpose The purpose of this article is to conduct an evidence-based systematic review on the accuracy of pure-tone or otoacoustic emission (OAE) screening for identifying hearing loss in preschool- and school-age children. Method A systematic search of the literature published between 1975 and 2013 was conducted. Articles meeting the selection criteria were critically appraised for quality. Selection criteria required that behavioral thresholds be measured in children failing the screen and in at least a subset of children passing the screen. Sensitivity and specificity were used to calculate positive and negative likelihood ratios that could be compared between instruments. Results Eighteen studies were included in the final analysis. There was considerable variability among studies on stimulus levels, response criteria, and definition of hearing loss. Approximately half of positive and negative likelihood ratio pairs for OAEs (52%) and pure-tone screening (45%) were considered suggestive or informative for identifying hearing loss. Conclusions Both pure-tone and OAE screening can identify hearing loss in preschool- and school-age children. Studies that compared both tools in the same population concluded that pure-tone screening had higher sensitivity than OAE screening and thus was considered the preferred tool. Future research should incorporate standard stimulus levels, response criteria, and definitions of hearing loss.

In this paper, we consider orthogonal multiple access coded schemes with correlated sources. The sources are distributedly encoded and their correlation is exploited at the access point (AP). In particular, we assume that each source uses a classical channel code to transmit, through an additive white Gaussian noise (AWGN) channel, its information to the AP. Here component decoders, associated with the source encoders, iteratively exchange soft information by taking into account the source correlation. The key goal of this paper is to investigate the ultimate achievable performance limits in terms of a multidimensional feasible region in the space of channel parameters, deriving insights on the impact of the number of sources. In order to analyze the performance of given coded schemes, we propose an extrinsic information transfer (EXIT)-based approach, which allows to determine the corresponding multi-dimensional feasible regions. On the basis of the proposed analytical framework, the performance of pragmatic schemes, based on serially concatenated convolutional codes (SCCCs) and low-density parity-check (LDPC) codes, is discussed.

A number of modern storage technologies, when written to, exhibit substantial variability in the outcome of a write action. It is possible to mitigate the effect of the write uncertainty through the use of a feedback loop that rewrites the memory whenever judged necessary, in effect reshaping the write noise. This scheme highlights a tradeoff between the storage capacity of the memory and the cost of writing to it, measured for example in the number of rewrites. We have developed the model of a rewritable channel to provide an explicit form for this tradeoff and study other performance characteristics of such memories. In this paper, we describe some initial results on the information-theoretic analysis of the rewritable channel. We first consider the problem of determining the capacity of this channel with input cost constraints, and obtain a variety of results from which we extract insights that we believe are of value to memory designers. Our results include an upper bound on capacity of the form $\log\left(\Gamma\kappa\right)$ , where $\Gamma$ is a constant that can be easily calculated from the channel's statistics and $\kappa$ is an average cost parameter. We also provide a lower bound on capacity with a similar form. We analyze the particular case of uniform write noise in detail, obtaining a closed form expression for the capacity-cost tradeoff for all possible cost parameters. We explore this formula from the capacity per unit cost perspective and establish that in order to achieve optimal energy and memory-wear per bit, it is sometimes strictly better to take advantage of the rewriting capability as opposed to writing only once; this observation has significant practical implications. We also include a discussion of the relevance of our work to real emerging memory technologies.

Phase Change Memory (PCM) is a promising technology for building future main memory systems. A prominent characteristic of PCM is that it has write latency much higher than read latency. Servicing such slow writes causes significant contention for read requests. For our baseline PCM system, the slow writes increase the effective read latency by almost 2X, causing significant performance degradation.This paper alleviates the problem of slow writes by exploiting the fundamental property of PCM devices that writes are slow only in one direction (SET operation) and are almost as fast as reads in the other direction (RESET operation). Therefore, a write operation to a line in which all memory cells have been SET prior to the write, will incur much lower latency. We propose PreSET, an architectural technique that leverages this property to pro-actively SET all the bits in a given memory line well in advance of the anticipated write to that memory line. Our proposed design initiates a PreSET request for a memory line as soon as that line becomes dirty in the cache, thereby allowing a large window of time for the PreSET operation to complete. Our evaluations show that PreSET is more effective and incurs lower storage overhead than previously proposed write cancellation techniques. We also describe static and dynamic throttling schemes to limit the rate of PreSET operations. Our proposal reduces effective read latency from 982 cycles to 594 cycles and increases system performance by 34%, while improving the energy-delay-product by 25%.

Multicenter, prospective study.To assess the occurrence and predictors of return to work after traumatic spinal cord injury (SCI).Italian rehabilitation centers.We evaluated patients previously included in the Italian Group for the Epidemiological Study of Spinal Cord Injuries study. A standardised telephone interview was used to collect data after a mean follow-up of 3.8 years. The main outcome measure was employment at the end of follow-up.A total of 403 patients, 336 men and 67 women, with a mean age of 41.8±16.3 years, were included in the follow-up. In all, 42.1% of patients were employed at the moment of the interview, though 62% reported a worsening in their employment level. Predictors of employment were education (P0.0001), bowel continence (P=0.02), independence in mobility (P=0.0004), ability to drive (P0.0001), participating in the community (P=0.0001) and ability to live alone (P0.0001) while age (P0.0001), being married (P0.0001), tetraplegia (P=0.03), occurrence of recent medical problems (P=0.002), re-hospitalization (P=0.02), presence of architectonic barriers (P=0.009) and having a public welfare subsidy (P0.0001), predicted unemployment. On the basis of multivariate analysis, younger age, education, absence of tetraplegia, ability to drive, ability to live alone, previous employment were independent predictors of employment after SCI. Employment at follow-up was related to several indicators of quality of life.Employment after SCI was rather frequent and was related to several patient characteristics and social factors. Specific interventions on the patient and on the social environment may favor employment after SCI and improve quality of life.

Purpose To report the outcome of a consecutive series of patients with nonmetastatic nasopharyngeal carcinoma (NPC), focusing on the impact of treatment-related factors. Methods and Materials Between 2000 and 2006, 87 patients with NPC were treated with either conventional (two- or three-dimensional) radiotherapy (RT) or with intensity-modulated RT (IMRT). Of these patients, 81 (93%) received either concomitant CHT (24%) or both induction and concomitant chemotherapy (CHT) (69%). Stage was III in 36% and IV in 39% of patients. Outcomes in this study population were compared with those in the previous series of 171 patients treated during 1990 to 1999. Results With a median follow-up of 46 months, actuarial rates at 3 years were the following: local control, 96%; local-regional control, 93%; distant control (DC), 90%; disease-free survival (DFS), 82%; overall survival, 90%. In Stage III to IV patients, distant control at 3 years was 56% in patients treated with concomitant CHT only and 92% in patients treated with both induction and concomitant CHT ( p = 0.014). At multivariate analysis, histology, N-stage, RT technique, and total RT dose had the strongest independent impact on DFS ( p p = 0.07). Most dosimetric statistics were improved in the group of patients treated with IMRT compared with conventional 3D technique. All outcome endpoints were substantially better in the study population compared with those in the previous series. Conclusions Outcome of NPC has further improved in the study period compared with the previous decade, with a significant effect of RT technique optimization. The impact of induction CHT remains to be demonstrated in controlled trials.

In this paper, we present a novel pragmatic approach, referred to as detection by multiple trellises, to perform trellis-based detection over realistic channels. More precisely, we consider channels with unknown parameters and apply the concept of detection by multiple trellises to forward-backward (FB) algorithms. The key idea of our approach consists, first, of properly quantizing the channel parameters and, then, considering replication of coherent FB algorithms operating on parallel trellises, one per hypothetical quantized value. In order to make the receiver robust against a possibly time-varying channel parameters, the proposed soft-output algorithms perform a proper "manipulation" of the forward and backward metrics computed by the parallel FB algorithms at regularly spaced trellis steps. We consider two significant examples of application: detection over (i) phase-uncertain channels and (ii) fading channels. The performance of the proposed algorithms is investigated considering differentially encoded (DE) quaternary phase shift keying (QPSK) and iterative detection schemes based on low-density parity-check (LDPC) codes. Besides having a low complexity, the proposed soft-output algorithms turn out to be robust, flexible, blind, in the sense that no knowledge of the channel parameter statistics is required, and highly parallelizable, as it is desirable in high-throughput future wireless communication systems.

In this paper, we investigate the ultimate performance limits, in terms of achievable information rate (IR), of communication systems impaired by impulse noise. We compare single carrier (SC) and multi-carrier (MC) transmission systems employing quadrature amplitude modulation (QAM) formats. More precisely, we consider SC schemes with coded modulations and MC systems based on orthogonal frequency division modulation (OFDM). For the MC schemes, we introduce a theoretically equivalent channel model which makes the computation of the IR feasible. This simple channel model will be referred to as interleaved MC. We show that, in the presence of impulse noise and except for systems operating at very high spectral efficiency, the IR of MC schemes is lower than that of SC schemes. More precisely, use of MC schemes may lead to an unavoidable fundamental loss with respect to SC schemes at typical coding rates, whereas MC schemes are to be preferred for very high coding rates or in uncoded systems. These results hold for additive white Gaussian noise (AWGN) and dispersive channels, either considering plain OFDM or MC schemes employing water-filling and bit-loading algorithms. In order to validate our theoretical results, we also obtain the bit error rate (BER) performance of SC and MC schemes through Monte Carlo simulations. A few trellis-coded modulation (TCM) and low-density parity-check (LDPC)-coded schemes are considered. The obtained SNR loss in the BER curves between the AWGN and impulse noise channels matches well with the corresponding IR gap.

We investigate the impact of state-complexity reduction on the performance of maximum likelihood sequence detection (MLSD) receivers for direct-photodetection long-haul optical communication systems affected by uncompensated chromatic dispersion (CD). We directly compare two possible approaches: (i) detection through a simple ldquobrute-forcerdquo state-complexity reduction strategy and (ii) a more structured reduced-state sequence detection (RSSD) strategy. The performance of both state-complexity reduction techniques is evaluated considering two realistic optical transmission schemes, based on on-off keying (OOK) and optical duobinary modulation (ODBM), respectively. The detection algorithms are characterized considering the impact of the timing offset, the quantization scheme, and the amount of uncompensated CD. As one would expect, for a given number of states in MLSD receivers, the schemes based on RSSD exhibit better performance with respect to those based on simple brute-force state-complexity reduction. However, we show that MLSD schemes based on the use of brute-force state-complexity reduction are characterized by a better complexity/performance trade-off for low/medium CD values, whereas RSSD is the best choice for high CD values.

Electronic signal processing is becoming very attractive to overcome various impairments that affect optical communications, and electronic dispersion compensation (EDC) represents a typical application in the currently designed systems. However, the inherent limits in performance achievable by electronically processing the signal at the output of a nonlinear photodetector have not received the attention they deserve. In this paper, we investigate the information-theoretic limits of electronic signal processing in transmission systems employing direct photodetection and two possible modulation formats: 1 on-off keying (OOK) with nonreturn-to-zero pulses; and 2 optical duobinary modulation (ODBM). The analysis is based on the computation of the information rate, i.e., the maximum achievable data transfer rate, and accounts for the modulation format as well as relevant parameters of the transmission scheme. In particular, we investigate the impact of sampling rate, uncompensated chromatic dispersion (CD), and quantization resolution of the electrical signal at the output of a direct photodetector. For OOK systems, the obtained results show that the optical signal-to-noise ratio penalty entailed by EDC can be limited to about 2 dB at most values of CD of interest in current applications. Moreover, ODBM systems at high values of CD can almost perform as OOK systems at zero CD. For all the considered modulation formats, the obtained results show that the received electrical signal can be sampled at a rate of two samples per bit interval and quantized with a precision of 3 bits per sample to practically achieve the ultimate performance limits.

In this letter, we discuss the performance of low-density parity-check (LDPC) codes on memoryless channels. Using a recently proposed analysis technique based on extrinsic information transfer (EXIT) charts, we present an interpretation of the known fact that the bit-error rate (BER) performance of an ensemble of LDPC codes shows little dependence on the specific memoryless channel. This result has been partially observed in the literature for symmetric channels and is here extended to asymmetric channels. We conjecture and demonstrate that the performance of an ensemble of LDPC codes depends primarily and solely on the mutual information (MI) between the input and the output of the channel. As a validation of this conjecture, we compare the performance of a few LDPC codes with various rates for five representative memoryless (both symmetric and asymmetric) channels, obtaining results in excellent agreement with the EXIT chart-based prediction

In this paper, we consider serially concatenated schemes with outer novel and efficient low-density parity-check (LDPC) codes and inner modulations effective against channel impairments. With a pragmatic approach, we show how to design LDPC codes tailored for simple and robust modulation formats, such as differentially encoded (DE) modulations. The LDPC codes are optimized through the use of a recently proposed analysis technique based on extrinsic information transfer (EXIT) charts. In particular, we optimize, through a "clever" random walk in the parametric space, the degree distributions of the outer LDPC codes, obtaining significant insights on the impact of such distributions on the performance of the proposed concatenated schemes. The optimization is carried out for transmission over both the additive white Gaussian noise channel and a noncoherent channel. The performance predicted by the EXIT chart-based optimization is confirmed by results obtained via computer simulations, considering phase-shift keying and quadrature amplitude modulation at the transmitter side, and iterative demodulation/decoding at the receiver side. The significance of the proposed optimized design of LDPC-coded schemes with DE modulations is validated by the fact that standard nonoptimized LDPC codes perform poorly when used together with inner DE modulations.

Purpose This is a systematic review of assessment and treatment of cognitive and communicative abilities of individuals with acquired brain injury via telepractice versus in person. The a priori clinical questions were informed by previous research that highlights the importance of considering any functional implications of outcomes, determining disorder- and setting-specific concerns, and measuring the potential impact of diagnostic accuracy and treatment efficacy data on interpretation of findings. Method A literature search of multiple databases (e.g., PubMed) was conducted using key words and study inclusion criteria associated with the clinical questions. Results Ten group studies were accepted that addressed assessment of motor speech, language, and cognitive impairments; assessment of motor speech and language activity limitations/participation restrictions; and treatment of cognitive impairments and activity limitations/participation restrictions. In most cases, equivalence of outcomes was noted across service delivery methods. Conclusions Limited findings, lack of diagnostic accuracy and treatment efficacy data, and heterogeneity of assessments and interventions precluded robust evaluation of clinical implications for telepractice equivalence and the broader area of telepractice efficacy. Future research is needed that will build upon current knowledge through replication. In addition, further evaluation at the impairment and activity limitation/participation restriction levels is needed. Supplemental Material https://doi.org/10.23641/asha.6170234

Storage class memory is receiving increasing attention for use in HPC systems for the acceleration of intensive IO operations. We report a particular instance using SLC FLASH memory integrated with an IBM BlueGene/Q supercomputer at scale Blue Gene Active Storage, BGAS. We describe two principle modes of operation of the non-volatile memory: 1 block device; 2 direct storage access DSA. The block device layer, built on the DSA layer, provides compatibility with IO layers common to existing HPC IO systems POSIX, MPIO, HDF5 and is expected to provide high performance in bandwidth critical use cases. The novel DSA strategy enables a low-overhead, byte addressable, asynchronous, kernel by-pass access method for very high user space IOPs in multithreaded application environments. Here, we expose DSA through HDF5 using a custom file driver. Benchmark results for the different modes are presented and scale-out to full system size showcases the capabilities of this technology.

Lo sviluppo delle moderne tecniche di immagini non invasive ha determinato un notevole progresso nelle conoscenze del recupero funzionale dopo ictus, potenzialmente di grande utilità per la messa a punto di programmi terapeutici e riabilitativi. Diversi meccanismi sono stati proposti, quali l'attivazione di vie derivanti dalle aree corticali motorie omolaterali al lato paretico, il reclutamento di aree corticali adiacenti alla lesione, il rinforzo di circuiti neuronali preesistenti, lo stabilirsi di nuove connessioni a livello sinaptico. Considerati i dati contraddittori della letteratura, abbiamo effettuato un studio mediante Risonanza Magnetica funzionale (fMRI) con lo scopo di definire meglio il ruolo delle proiezioni omolaterali e i fenomeni di riorganizzazione plastica post-ictale delle aree corticali motoria primaria (M1), premotoria laterale (PML) e supplementare motoria (SMA). Sono stati studiati 14 pazienti con pregresso ictus ischemico sottocorticale in buon recupero funzionale, 7 con emiparesi destra e 7 con emiparesi sinistra, ad una distanza mediana di 61 giorni dall'evento ischemico. I risultati hanno evidenziato durante il movimento della mano paretica un'attivazione bilaterale della M1 ed in misura minore delle PML e SMA, mentre si è registrata un'attivazione controlaterale più selettiva durante il movimento della mano sana. I dati sembrerebbero dimostrare che una maggiore attivazione delle aree motorie corticali omolaterali alla lesione sia un importante meccanismo di compenso al danno funzionale conseguente ad ictus non solo nella fase postacuta ma anche nella fase di stabilizzazione.

1H-MRS examinations were carried out on 14 patients, recovering from traumatic brain injury (TBI), who were in a stabilized clinical status and showed a good clinical outcome. Magnetic resonance spectra were recorded in subcortical (SC) and mid-brain (MB) areas where no detectable lesions appeared under magnetic resonance imaging. These two brain areas were selected because they are crucial sites of damage due to the physiopathologic mechanisms of TBI. A significant increase in inositol and choline peaks was found in MB compared to a control group of healthy individuals, whereas lower N-acetyl-aspartate peaks in the same area were detected. Reduced levels in the latter metabolite were also evident in the SC area. A significant correlation emerged between the inositol concentration in MB and the Glasgow Coma Scale Score measured just after the trauma. No correlation was found between the Glasgow Outcome Scale (GOS) at the time of the 1H-MRS examination and the peaks of all the metabolites. Our study demonstrated that 1H-MRS is a sensitive tool to evidentiate brain metabolic damage after TBI even in areas with lesions that are not detectable with current imaging techniques. The present research also shows an association between the alteration in one of the brain metabolites and the clinical parameters of TBI severity, but does not provide a clinical index of the patient's recovery. Further longitudinal studies on more conspicuous groups of patients with TBI could help to clarify whether metabolite modifications revealed by 1H-MRS could be predictive of clinical outcome.

Aim: To analyze the patterns of locoregional failure following intensity-modulated radiotherapy (IMRT) for nasopharyngeal carcinoma (NPC) at our institution, as part of an internal quality assurance program. We aimed to investigate the potential existence of a correlation between any part of the IMRT process and clinical outcome. Methods & materials: A total of 106 non-metastatic NPC patients consecutively treated with IMRT (with or without chemotherapy) were analyzed. Radiotherapy was administered using a sequential or simultaneous integrated boost approach at the total prescribed dose of 66–70 Gy (2.00–2.12 Gy per fraction). MRI studies of recurrences were recorded with the planning computed tomography studies to identify volume of failure. Recurrence-related characteristics were analyzed with respect to the original treatment. Failures were classified as ‘in-field’, ‘marginal’ or ‘out-field’ if at least 95, 20–95 or less than 20% of the volume of failure, respectively, was within 95% of the total prescription dose. Results: With a median follow-up of 43.4 months, 5-years local control, regional control, locoregional control and overall survival rates were 87.7, 88.0, 83.5 and 81.3% respectively. A total of 21 failures were registered in 15 patients. In particular, ten failures (47.6%) were classified as ‘in-field’ (seven local failures and three regional failures [RFs]), nine failures (42.9%) as ‘marginal’ (five local failures and four RFs) and only two failures (9.5%) as ‘out-field’ (both RFs). The most relevant causes of failures were suboptimal target definition and target coverage as well as a longer than planned overall treatment time. Conclusion: IMRT determines excellent outcome in NPC patients. However, great attention in all IMRT steps is necessary to reduce potential causes of failure.

Difficulty in walking is a major feature of neurological disease, and loss of mobility is the activity of daily living on which patients place the greatest value. The impact on patients is enormous, with negative ramifications on their participation in social, vocational, and recreational activities. In current clinical practice the gait restoration with robotic device is an integral part of rehabilitation program. Robot therapy involves the use of a robot exoskeleton device or end-effector device to help the patient retrain motor coordination by performing well-focused and carefully directed repetitive practice. The exoskeleton, as an assistive device, is also an external structural mechanism with joints and links corresponding to those of the human body. These robots use joint trajectories of the entire gait cycle and offer a uniform (more or less) stiff control along this trajectory. In this field the new powered exoskeleton ReWalk (Argo Medical Technologies Ltd) was developed to have an alternative mobility solution to the wheelchair and rehabilitation treatment for individuals with severe walking impairments, enabling them to stand, walk, ascend/descent stairs and more. The end-effector-based robot is a device with footplates placed on a double crank and rocker gear system. Alternatives to powered exoskeletons are devices that use movable footplates to which the patient's feet are attached. All devices include some form of body weight support. Prominent goals in the field include: developing implementable technologies that can be easily used by patients, therapists, and clinicians; enhancing the efficacy of clinician's therapies and increasing the ease of activities in the daily lives of patients.

Mirror neurons are a specific class of neurons that are activated and discharge both during observation of the same or similar motor act performed by another individual and during the execution of a motor act. Different studies based on non invasive neuroelectrophysiological assessment or functional brain imaging techniques have demonstrated the presence of the mirror neuron and their mechanism in humans. Various authors have demonstrated that in the human these networks are activated when individuals learn motor actions via execution (as in traditional motor learning), imitation, observation (as in observational learning) and motor imagery. Activation of these brain areas (inferior parietal lobe and the ventral premotor cortex, as well as the caudal part of the inferior frontal gyrus [IFG]) following observation or motor imagery may thereby facilitate subsequent movement execution by directly matching the observed or imagined action to the internal simulation of that action. It is therefore believed that this multi-sensory action-observation system enables individuals to (re) learn impaired motor functions through the activation of these internal action-related representations. In humans, the mirror mechanism is also located in various brain segment: in Broca's area, which is involved in language processing and speech production and not only in centres that mediate voluntary movement, but also in cortical areas that mediate visceromotor emotion-related behaviours. On basis of this finding, during the last 10 years various studies were carry out regarding the clinical use of action observation for motor rehabilitation of sub-acute and chronic stroke patients.