Capacity-achieving CPM schemes

The pragmatic approach to coded continuous-phase modulation (CPM) is proposed as a capacity-achieving low-complexity alternative to the serially-concatenated CPM (SC-CPM) coding scheme. In this paper, we first perform a selection of the best spectrally-efficient CPM modulations to be embedded into SC-CPM schemes. Then, we consider the pragmatic capacity (a.k.a. BICM capacity) of CPM modulations and optimize it through a careful design of the mapping between input bits and CPM waveforms. The so obtained schemes are cascaded with an outer serially-concatenated convolutional code to form a pragmatic coded-modulation system. The resulting schemes exhibit performance very close to the CPM capacity without requiring iterations between the outer decoder and the CPM demodulator. As a result, the receiver exhibits reduced complexity and increased flexibility due to the separation of the demodulation and decoding functions.Comment: Submitted to IEEE Transactions on Information Theor

“Trascinando muli e sofferenze”: la Grecia lontana di Mario Rigoni Stern

This article aims to analyse the reasons for the unexpected absence of Greece in Mario Rigoni Stern’s works about the Italian military campaign against Greece during the winter of 1940-1941. As a young soldier, Rigoni Stern fought in that terrible war in the Albanian mountains, close to the Greek line, and recounted those events many years later. I focus in particular on Quota Albania (1971), in an attempt to show that the novel is not only a memoir, but rather a Bildungsroman, in which he recounts his personal life, his disillusionment with Italian disorganisation and the difficult conditions he endured, the cold and hunger. Furthermore, I would like to explain that the surprising indifference to Greek events is linked not only to the author’s narrative intention, but also to the fact that in the final battle Rigoni Stern did not go to Greece, and never returned thereafter. On the other hand, his unfamiliarity with the Mediterranean justifies the lack of descriptive details of the Greek landscape

Comparison between Coherent and Noncoherent Receivers for UWB Communications

We present a comparison between coherent and noncoherent UWB receivers, under a realistic propagation environment, that takes into account also the effect of path-dependent pulse distortion. As far as coherent receivers are concerned, both maximal ratio combining (MRC) and equal gain combining (EGC) techniques are analyzed, considering a limited number of estimated paths. Furthermore, two classical noncoherent schemes, a differential detector, and a transmitted-reference receiver, together with two iterative solutions, recently proposed in the literature, are considered. Finally, we extend the multisymbol approach to the UWB case and we propose a decision-feedback receiver that reduces the complexity of the previous strategy, thus still maintaining good performance. While traditional noncoherent receivers exhibit performance loss, if compared to coherent detectors, the iterative and the decision-feedback ones are able to guarantee error probability close to the one obtained employing an ideal RAKE, without requiring channel estimation, in the presence of static indoor channel and limited multiuser interference

Guerra vs comunità: la «Trilogia dell’Altipiano» di Mario Rigoni Stern

La Trilogia dell’Altipiano di Mario Rigoni Stern può essere considerata un’opera coerente per diversi motivi: le tre storie raccontate hanno una comune ambientazione geografica, la piana di Asiago, che presenta un legame molto forte con la popolazione locale; le vicende narrate si pongono in consequenzialità cronologica e mostrano figure che tornano in tutti e tre i testi, comprendendo anche personaggi della famiglia dell’autore. Tale coerenza narrativa si riflette nel messaggio della Trilogia, che è un messaggio di pace e di denuncia della guerra come elemento di distruzione della comunità umana, raffigurata emblematicamente dall’allegoria del ciliegio che torna in tutte e tre le narrazioni. Finita la guerra, alla comunità e alla natura si oppone il consumismo moderno, che cancella le tracce dell’antica civilità alpina e contro cui Rigoni Stern si impegna come custode della memoria attraverso la parola narrata

Nitrogen uptake and nitrogen fertilizer recovery in old and modern wheat genotypes grown in the presence or absence of interspecific competition

Choosing genotypes with a high capacity for taking up nitrogen (N) from the soil and the ability to efficiently compete with weeds for this nutrient is essential to increasing the sustainability of cropping systems that are less dependent on auxiliary inputs. This research aimed to verify whether differences exist in N uptake and N fertilizer recovery capacity among wheat genotypes and, if so, whether these differences are related to a different competitive ability against weeds of wheat genotypes. To this end, 12 genotypes, varying widely in morphological traits and year of release, were grown in the presence or absence of interspecific competition (using Avena sativa L. as a surrogate weed). Isotopic tracer 15N was used to measure the fertilizer N uptake efficiencies of the wheat genotypes and weed. A field experiment, a split-plot design with four replications, was conducted during two consecutive growing seasons in a typical Mediterranean environment. In the absence of interspecific competition, few differences in either total N uptake (range: 98–112 kg N ha–1) or the 15N fertilizer recovery fraction (range: 30.0–36.7%) were observed among the wheat genotypes. The presence of competition, compared to competitor-free conditions, resulted in reductions in grain yield (49%), total N uptake (29%), and an 15N fertilizer recovery fraction (32%) that were on average markedly higher in modern varieties than in old ones. Both biomass and grain reductions were strongly related to the biomass of the competitor (correlation coefficients > 0.95), which ranged from 135 g m–2 to 573 g m–2. Variations in both grain and biomass yield due to interspecific competition were significantly correlated with percentage of soil cover and leaf area at tillering, plant height at heading, and total N uptake, thus highlighting that the ability to take up N from the soil played a certain role in determining the different competitive abilities against weed of the genotypes

The New Youth of the In Situ Transmission Electron Microscopy

The idea of in situ transmission electron microscopy (TEM) and its possible ramifications were proposed at the very dawn of electron microscopy, but the translation from theory to practice encountered many technological setbacks, which hindered the feasibility of the most elaborated approaches until recent times. However, the several technological improvements achieved in the last 10–15 years filled this gap, allowing the direct observation of the dynamic response of materials to external stimuli under a vast range of conditions going from vacuum to gaseous or liquid environment. This resulted in a blossoming of the in situ TEM and scanning TEM (STEM) techniques to a new youth for a vast, growing range of applications, which cannot be rightfully detailed in a short span; therefore, this chapter should be intended as a guide highlighting a selection of the most inspiring, recently achieved results

Understanding Cassiopea andromeda (Scyphozoa) Invasiveness in Different Habitats: A Multiple Biomarker Comparison

A dual nutrition mode (i.e., mixotrophy) can be advantageous for alien species in a new environment. In Ceara (Brazil), the symbiotic jellyfish Cassiopea andromeda is rapidly spreading under diverse environmental conditions across natural and human-altered coastal habitats, such as mangroves and shrimp farms. Here we report on the trophic ecology of the alien upside-down jellyfish sampled in these two contrasting coastal habitats during the dry (July-October) and rainy (January-April) seasons, investigated by means of organic biomarkers (lipids, carbohydrates) and bulk tissue stable isotope (& delta;N-15 and & delta;C-13) analyses. Total lipid content of jellyfish gonads was generally higher in shrimp farms, whereas no significant difference in carbohydrate concentration was found in jellyfish tissues from the two different habitats. Similarly, there were no significant differences in the & delta;N-15 values of jellyfish tissues from the two contrasting habitats, whereas the & delta;C-13 values were higher in jellyfish from shrimp farms. Overall, the higher carbon-enriched value in aquaculture ponds supports the hypothesis of differences of available food sources compared to the natural mangrove habitats, where food availability exhibits a stronger seasonality. In fact, aquaculture ponds are characterized by human-driven regular food supply, leading to more stable trophic conditions and to enhanced growth, lipid production, and gonadal output of C. andromeda jellyfish. This investigation may contribute to predicting how Cassiopea mixotrophy may contribute to explaining its differential success in different habitats

PTP4A1 promotes TGFβ signaling and fibrosis in systemic sclerosis.

Systemic sclerosis (SSc) is an autoimmune disease characterized by fibrosis of skin and internal organs. Protein tyrosine phosphatases have received little attention in the study of SSc or fibrosis. Here, we show that the tyrosine phosphatase PTP4A1 is highly expressed in fibroblasts from patients with SSc. PTP4A1 and its close homolog PTP4A2 are critical promoters of TGFβ signaling in primary dermal fibroblasts and of bleomycin-induced fibrosis in vivo. PTP4A1 promotes TGFβ signaling in human fibroblasts through enhancement of ERK activity, which stimulates SMAD3 expression and nuclear translocation. Upstream from ERK, we show that PTP4A1 directly interacts with SRC and inhibits SRC basal activation independently of its phosphatase activity. Unexpectedly, PTP4A2 minimally interacts with SRC and does not promote the SRC-ERK-SMAD3 pathway. Thus, in addition to defining PTP4A1 as a molecule of interest for TGFβ-dependent fibrosis, our study provides information regarding the functional specificity of different members of the PTP4A subclass of phosphatases

Penile Length Assessment of Children Treated for Primary Buried Penis: Can Satisfying Penile Growth Always Be Achieved?

Primary buried (BP) penis is describes as a small penis caused by a penile ligaments anomaly; it is unclear if a primary BP could reach a normal length. We selected 49 patients treated at our institution between 2015 and 2020 in order to post-operatively evaluate the SPL after one year. SPL was evaluated according to the PH Tanner staging system for pre-pubertal patients according to age-normalized values. A micropenis was detected if the SPL was below 2.5 SD. A normal SPL was found in thirty-two patients, eighteen were in PH Stage 1, four were in PH Stage 2, six were in PH Stage 3, and four were in PH Stage 5. Seventeen patients showed a reduced SPL; in seven of these (four in PH Stage 4 and three in PH Stage 5), their SPL was <2.5 ST. The difference in micropenis prevalence between the pre-pubertal and post-pubertal patients was significant (p = 0.038). A primary BP grows normally during the pre-pubertal period, where patients frequently showed a normal SPL, but it seems to be unable to reach a normal length in the higher PH stages, where the SPL is used to detect a micropenis. We suggest that a primary BP should be considered not as a simple defect of the penile ligaments and surrounding tissues, but as an incomplete manifestation of a micropenis due to a growth slowdown of the organ in late puberty