Adaptive data synchronization algorithm for IoT-oriented low-power wide-area networks

The Internet of Things (IoT) is by now very close to be realized, leading the world towards a new technological era where people’s lives and habits will be definitively revolutionized. Furthermore, the incoming 5G technology promises significant enhancements concerning the Quality of Service (QoS) in mobile communications. Having billions of devices simultaneously connected has opened new challenges about network management and data exchange rules that need to be tailored to the characteristics of the considered scenario. A large part of the IoT market is pointing to Low-Power Wide-Area Networks (LPWANs) representing the infrastructure for several applications having energy saving as a mandatory goal besides other aspects of QoS. In this context, we propose a low-power IoT-oriented file synchronization protocol that, by dynamically optimizing the amount of data to be transferred, limits the device level of interaction within the network, therefore extending the battery life. This protocol can be adopted with different Layer 2 technologies and provides energy savings at the IoT device level that can be exploited by different applications

ASK-based spatial multiplexing RGB scheme using symbol-dependent self-interference for detection

We propose a vsible light communication scheme utilizing red, green and blue lightemitting diodes (LEDs) and three color-Tuned photodiodes. Amplitude shift keying modulation is considered, and its effect on light emission in terms of flickering, dimming, and color rendering is discussed. The presence of interference at each photodiode generated by the other two colors is used to improve detection since interference is symbol-dependent. Moreover, the capability of the photodiodes to follow the LEDs speed is considered by analyzing the possibility of equalizing the received signal, and also self-interference mitigation is proposed. The system performance is evaluated both with computer simulations and tests on an Arduino board implementation

MIMO underwater acoustic communications over time-varying channels: from theory to practice

Despite more than 70% of our planet surface is covered by water, today the underwater world can still be considered largely unknown. Rivers, lakes, seas and oceans have always been a fundamental resource for human life development, but at the same time they have often represented natural obstacles very hard to surmount. The most impressive example is probably given by the ocean, whose vastness severely limited geographical explorations and discoveries for tens of centuries. Anyway, the growing curiosity about what happens below the water surface has gradually led man to immerse in this unknown environment, trying to overcome its inaccessibility and figure out its secrets. Underwater investigation and exploring have been increasingly supported by technology, advanced over time for different purposes (military, commercial, scientific). In this regard, providing a communication link between remote users has been recognized as one of the main issues to be addressed. The first significant solutions derived from the radio-frequency world, subject of study since the 19th century. Unfortunately both wired and wireless RF inspired signal propagation strategies were not evaluated as successful. The former ones, since considering the deployment of meters (up to kilometers) of cable in depth, were too costly and difficult, while the latter ones did not offer good performance in terms of communication range due to signal attenuation. An alternative way, examined with particular interest from the beginning of the 20th century, has been that one offered by acoustics. Actually, the study of sound and its propagation through different media has been an intriguing topic since the Old World Age, hence the attempt of messaging underwater has seemed to be a great opportunity to convey theoretical principles in a real application. In addition, not only humans but also marine animals use acoustic waves to communicate, even over several kilometers distances as demonstrated by whales. So, since already existing in nature, acoustic communications have been considered as potentially successful, furthermore representing an effective trade-off between feasibility and performance, especially if compared to the other electromagnetic signals-based methods. Communication over RF channels has been extensively investigated so as to become a mature technology. The thorough knowledge about OSI (Open Systems Interconnection) model physical layer issues has allowed the researchers attention to be drawn to the upper layers. Following this direction, the recent advances in technology in this field have been accomplished mainly due to novelties in networks managing rather than to enhancements in the signal propagation study. Moving to acoustics, unfortunately this approach results to be failing if applied in the underwater scenario, as the major challenges rise indeed from physics matters. The underwater environment is varied and variable, so understanding the mechanisms that govern the propagation of sound in water is a key element for the design of a well-performing communication system. In this sense, the physical layer has therefore regained the centrality that has been diminished in other contexts. The underwater acoustic communications can be adopted in a wide range of applications. The best-known are coastal monitoring, target detection, AUVs (Autonomous Underwater Vehicles) remote control, tsunami alarm, environmental data collection and transmission. Those ones are very specific activities, so the devices to be employed must sometimes meet very strict requirements. In this regard, the solutions commercially available provide good performance (that are paid in terms of high costs). On the other hand, the fact that hardware and software are usually copyrighted leads to have a closed system. Having reconfigurable devices is instead an opportunity to match the technology with the environment features and variations, especially in real-time applications. Recently, the need to overcome these constraints has encouraged the debate about underwater technology challenges. The work by Demirors et al. [1] reports an interesting discussion about the implementation of software-defined underwater acoustic networks (UWANs), highlighting how this solution can provide enhancements in terms of software portability, computational capacity, energy efficiency and real-time reconfigurability. Furthermore, the authors propose the architecture of a software-defined acoustic modem and evaluate its performance and capabilities with tank and lake experiments. Considering the comments outlined above, the following dissertation deals with the design of an acoustic communication system. The preliminary theoretical analysis regarding physical layer concerns, such as signal propagation and channel behavior, represents the starting point from which several proposals regarding the implementation of UWANs are introduced. In particular the context of Multiple-Input Multiple-Output (MIMO) communications is investigated, presenting several solutions about transmission schemes and receiver implementation. Furthermore, concerning UWANs management, some strategies for access and error control, established at the data link layer level, are detailed. It is worth highlighting that the goal of this contribution is not to present a disjointed discussion about the topics just listed. The objective is instead to propose practical solutions developed hand in hand with theory, making choices firstly by looking at what nature allows

Possible effects of hyperparathyroidism in the loss of osseointegration of dental implants: A case report

Background: Hyperparathyroidism (HPT) is a common endocrine disorder with potential complications on the skeletal, renal, neurocognitive and cardiovascular systems. Its association with the lack of osseointegration of dental implants hasnot been describedin the medical literature. Case presentation: This case report aims to discuss two cases of dental implant loss in which a high level of parathormone (PTH) was found in the absence of any other systemic or local comorbidity, suggesting the possible correlation between HPT and implant.Both patients were referred to the clinic complaining about prosthetic complications, gingival inflammation and mobility of the dental prosthesis. After a Cone-Beam computed Tomography evaluation, all implants of both patients were removed for rejection arising from periimplantitis and then four implants were inserted in the patient 1 and five implants in the patient 2. For both patientsshort implants (Bicon LLC, Boston, Massachusetts, USA), featured by 4 mm in diameter and 5 mm in height, were used and the prosthesis substructure was made of Trinia® (Bicon LLC, Boston, Massachusetts, USA). During the fifth year, the patients reported complications and the implant treatment failure. In order to establish the causes of failure, a thorough investigation was performed. Since no causes were detected, the patients were required to perform a blood test to evaluate bone metabolism and specifically to assess parathyroid-hormone levels (PTH), calcium levels and vitamin D. Results: The results of the blood tests showednormal calcemia, vitamin D deficiency and elevated PTH levelsin both patients. After an endocrinologist’s consultation, secondary hyperparathyroidism was diagnosed. Conclusion: It is reasonable to assume that the loss of osseointegration of dental implants can be correlated with the effects of HPT

Serum 27-hydroxycholesterol in patients with primary biliary cirrhosis suggests alteration of cholesterol catabolism to bile acids via the acidic pathway

Reduced cholesterol synthesis has been reported in patients with primary biliary cirrhosis but no data are available on changes in cholesterol catabolism induced by the disease. Serum levels of 7α-hydroxycholesterol and 27-hydroxycholesterol have been measured in 25 patients (either normocholesterolemic or hypercholesterolemic) with primary biliary cirrhosis and in control subjects. To evaluate cholesterol synthesis, serum levels of lathosterol were measured, and campesterol and sitosterol were considered to reflect intestinal absorption and biliary elimination of sterols. In normocholesterolemic patients with primary biliary cirrhosis, lathosterol was significantly lower than in normocholesterolemic controls (P < 0.05) whereas no difference was found between hypercholesterolemic patients and hypercholesterolemic controls. Serum concentrations of sitosterol were significantly higher in both normocholesterolemic and hypercholesterolemic patients with primary biliary cirrhosis as compared with the respective controls (P < 0.01). In patients with primary biliary cirrhosis, serum 7α-hydroxycholesterol was slightly higher than in controls. 27-Hydroxycholesterol was significantly higher in hypercholesterolemic compared to normocholesterolemic controls (P < 0.05) and a significant linear correlation (r = 0.771; P < 0.001) was found between 27-hydroxycholesterol and cholesterol. In contrast, in patients with primary biliary cirrhosis, high cholesterol concentrations were not associated with increased serum levels of 27-hydroxycholesterol. Our data confirm that in patients with primary biliary cirrhosis, cholesterol synthesis and biliary elimination of sterols are impaired and also suggest that both the feedback regulation of retained bile acids on cholesterol 7α-hydroxylase and the scavenger effect on elevated serum cholesterol by cholesterol 27-hydroxylase are deficient in these patients.—Del Puppo, M., M. Galli Kienle, M. L. Petroni, A. Crosignani, and M. Podda. Serum 27-hydroxycholesterol in patients with primary biliary cirrhosis suggests alteration of cholesterol catabolism to bile acids via the acidic pathway. J. Lipid Res. 1998. 39: 2477–2482

The dominant allele Aft induces a shift from flavonol to anthocyanin production in response to UV-B radiation in tomato fruit

The introgression of the A ft allele into domesticated tomato induced a shift from flavonol to anthocyanin production in response to UV-B radiation, while the hp - 1 allele negatively influenced the response of flavonoid biosynthesis to UV-B. Introgression of the dominant allele Anthocyanin fruit (Aft) from Solanum chilense induces anthocyanin accumulation in the peel of tomato (Solanum lycopersicum L.) fruit. UV-B radiation can influence plant secondary metabolism regulating the expression of several genes, among which those involved in flavonoid biosynthesis. Here, we investigated whether post-harvest UV-B treatment could up-regulate flavonoid production in tomato fruits and whether the Aft allele could affect flavonoid biosynthesis under UV-B radiation. Mature green fruits of an anthocyanin-rich tomato mutant line (SA206) and of its wild-type reference, cv. Roma, were daily subjected to post-harvest UV-B treatment until full ripening. Up-regulation of CHS and CHI transcription by UV-B treatment induced flavonoid accumulation in the peel of cv. Roma. Conversely, UV-B decreased the total flavonoid content and CHS transcript levels in the SA206 peel. SA206 being a double mutant containing also hp-1 allele, we investigated also the behavior of hp-1 fruit. The decreased peel flavonoid accumulation and gene transcription in response to UV-B suggest that hp-1 allele is involved in the marked down-regulation of the flavonoid biosynthesis observed in SA206 fruit. Interestingly, in SA206, UV-B radiation promoted the synthesis of delphinidin, petunidin, and malvidin by increasing F3'5'H and DFR transcription, but it decreased rutin production, suggesting a switch from flavonols to anthocyanins. Finally, although UV-B radiation does not reach the inner fruit tissues, it down-regulated flavonoid biosynthesis in the flesh of both genotypes. This study provides, for the first time, evidence that the presence of the functional Aft allele, under UV-B radiation, redirects flavonoid synthesis towards anthocyanin production and suggests that the hp-1 allele negatively influences the response of flavonoid biosynthesis to UV-B

Tactile multisensing on flexible aluminum nitride

The integration of a polycrystalline material such as aluminum nitride (AlN) on a flexible substrate allows the realization of elastic tactile sensors showing both piezoelectricity and significant capacitive variation under normal stress. The application of a normal stress on AlN generates deformation of the flexible substrate on which AlN is grown, which results in strain gradient of the polycrystalline layer. The strain gradient is responsible for an additional polarization described in the literature as the flexoelectric effect, leading to an enhancement of the transduction properties of the material. The flexible AlN is synthesized by sputtering deposition on kapton HN (poly 4,4′- oxydiphenyl pyromellitimide) in a highly oriented crystal structure. High orientation is demonstrated by X-ray diffraction spectra (FWHM = 0.55° of AlN (0002)) and HRTEM. The piezoelectric coefficient d 33 and stress sensitive capacitance are 4.7 ± 0.5 pm V -1 and 4 × 10 -3 pF kPa -1, respectively. The parallel plate capacitors realized for tactile sensing present a typical dome shape, very elastic under applied stress and sensitive in the pressure range of interest for robotic applications (10 kPa to 1 MPa). The flexibility of the device finalized for tactile applications is assessed by measuring the sensor capacitance before and after shaping the sensing foil on curved surfaces for 1 hour. Bending does not affect sensors operation, which exhibits an electrical Q factor as high as 210, regardless of the bending, and a maximum capacitance shift of 0.02%

Configuration origin variants of superior Thyroid, Lingual and Facial Arteries: a proposal updating of current classification

Background: The aim of this study was to identify variations in the origins of the anterior branches of the external carotid artery (ECA) and to propose an update of the current classification. Methods: The study included 100 carotids arteries from fifty human donors. Classification of anterior branches of external carotid artery was performed according to Vaz'quez et al. (2009). Results: The configuration origins of anterior branches were found as follows: Type I, 82%; Type II, 1%; Type III, 16%. No Type IV was observed. The study identified seven subgroups of anterior branch variations in the external carotid artery. The most frequently observed variations were Subtype Ia in 40% (n = 20) of cases on the right side and Subtype Ib in 38% (n = 19) on the left side. In addition, a rare and previously unclassified configuration was observed in a 72-year-old male donor, where the carotid artery was pentafurcated on the left side. Conclusions: In conclusion, the presence of anatomical variants not previously included in the anterior external carotid artery branching classifications supports the consideration of a revision to the present classification system

Metachronous primary uterine cancer surgically resected during crizotinib treatment in a ALK-rearranged advanced lung adenocarcinoma

Rearrangements of the anaplastic lymphoma kinase (ALK) gene are present in 3% to 7% of nonsmall-cell lung cancers (NSCLCs). Patients harboring ALK rearrangements show very favourable outcomes if treated with targeted agents, among which crizotinib is the first and best studied. Crizotinib, an oral smallmolecule tyrosine kinase inhibitor of ALK, MET, and ROS1 kinases, is a very active and well tolerated drug. Nevertheless, the optimal therapy management with this new drug is still partially unknown, especially with regard to the safety of combined treatments. Recently, the integration of locoregional treatments has been proposed as a feasible multimodality strategy in selected patients with good clinical conditions and slowgrowing or oligoprogressive disease. In this report, a case of advanced lung adenocarcinoma, progressed after first line chemotherapy and re-biopsied detecting ALK rearrangement, is described. During crizotinib treatment the primary lung tumor showed an excellent regression; meanwhile a major surgery for a metachronous uterine cancer was safely and successfully carried out

Petogodišnje praćenje kratkih implantata ugrađenih u atrofičnu maksilu s istodobnim transkrestalnim podizanjem dna sinusa

Objective: Many authors have tried to face the anatomical limitations resulting from maxillary bone atrophy. Up to five millimeters bone height, the lateral sinus floor elevation is the most commonly used and validated strategy to achieve the prosthetic rehabilitation. However, the disadvantages of this technique are its invasiveness and delayed rehabilitation. The aim of this paper was to assess 5 years clinical outcome of implants placed with a technique that allows the percrestal sinus floor elevation and the immediate implant placement. Materials and Methods: 30 transcrestal sinus floor elevations with immediate implant placement were performed in severely atrophic maxillae. Implant survival, marginal bone level variation, harvested bone height variation and periodontal indices were assessed. Results: After a five year follow up none of the thirty implants were lost. The mean value of vertical harvested bone loss was 5%. The mean crestal bone loss was -0.33 mm (Standard Deviation (SD) 0.11 mm). The mean value of periodontal indices was respectively: PD 1.22 mm (SD 0.72 mm), PI 17.47% (SD 15.01 mm), BOP 9, 87 %.,( SD 19.17 mm). Conclusion: The results obtained are comparable with success criteria in implant rehabilitation. The reported technique proved to be successful in the population observed, with minimal trauma and reduced invasiveness.Svrha rada: Mnogi su se autori pokušali suočiti s anatomskim ograničenjima koja nastaju zbog atrofije maksilarne kosti. Do visine kosti od pet milimetara lateralno podizanje dna sinusa najčešće je korištena i potvrđena strategija za protetičku rehabilitaciju. No nedostatci te tehnike su invazivnost i odgođena rehabilitacija. Cilj ovoga rada bio je procijeniti petogodišnji klinički ishod ugrađenih implantata tehnikom koja omogućuje perkrestalno podizanje dna sinusa i imedijatnu ugradnju implantata. Materijali i metode: Obavljeno je 30 transkrestalnih podizanja dna sinusa s imedijatnom ugradnjom implantata u vrlo atrofiranu maksilu. Procijenjeni su preživljavanje implantata, varijacija razine marginalne kosti te varijacija visine kosti i parodontoloških indeksa. Rezultati: Nakon petogodišnjeg praćenja ni jedan od trideset implantata nije bio izgubljen. Srednja vrijednost vertikalnog gubitka kosti iznosila je 5 %. Srednji gubitak krestalne kosti bio je -0,33 mm [standardna devijacija (SD) 0,11 mm]. Srednja vrijednost parodontoloških indeksa bila je: PD 1,22 mm (SD 0,72 mm), PI 17,47 % (SD 15,01 mm), BOP 9, 87 %, (SD 19,17 mm). Zaključak: Dobiveni rezultati usporedivi su s kriterijima uspješnosti u implantološkoj rehabilitaciji. Prikazana tehnika pokazala se uspješnom u promatranoj populaciji, uz minimalne traume i smanjenu invazivnost