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We studied the programming dynamics in phase change memory cells. It is shown that programming in stand-alone cells is strongly affected by the parasitic capacitance in the measurement setup, leading to a current overshoot after threshold switching of the amorphous chalcogenide. This results in a parasitic melting and quenching of the active material, affecting the current distribution during program and the final phase distribution in the active material. The relevance of this artefact for real-device operation is discussed with reference to the value of the parasitic capacitance. [ABSTRACT FROM AUTHOR]

We propose Hazards&Robots, a dataset for Visual Anomaly Detection in Robotics. The dataset is composed of 324,408 RGB frames, and corresponding feature vectors; it contains 145,470 normal frames and 178,938 anomalous ones categorized in 20 different anomaly classes. The dataset can be used to train and test current and novel visual anomaly detection methods such as those based on deep learning vision models. The data is recorded with a DJI Robomaster S1 front facing camera. The ground robot, controlled by a human operator, traverses university corridors. Considered anomalies include presence of humans, unexpected objects on the floor, defects to the robot. Preliminary versions of the dataset are used in [1,3]. This version is available at [12]., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2023 The Author(s).)

Immunoglobulin A deficiency is the most common primary immunodeficiency defined as decreased serum level of IgA (less than 7 mg/dl) in the presence of normal levels of other immunoglobulin isotypes. Most individuals with IgA deficiency are asymptomatic and identified coincidentally. However, some patients may present with recurrent infections, allergic disorders and autoimmune manifestations, such as diabetes mellitus, Graves disease and celiac disease. The international literature has not produced any kind of review yet about intra-oral manifestations of selective IgA-deficiency. L.S., a 7-year-old Caucasian girl, was examined at our hospital. After she had undergone a professional dental cleaning, a symmetric, bilateral ulcerative gingivitis developed nearby the upper second primary molars. The gingival ulcers were persistent and did not disappear in the following 3 weeks. In the meantime, the young patient reported the presence of gastrointestinal symptoms. IgA serum level was 4.5 mg/dl, while the other isotypes levels were in the common range. The diagnosis of selective IgA-deficiency was formulated and the girl underwent further examination for the specific IgG autoantibodies in celiac disease, which were not present. Consequently, a full prevention program was planned. This case report emphasizes the role of the paediatric dentist in the early detection of systemic disorder, such as the immunological diseases. The oral cavity often reveals to be the first site of manifestation of important systemic diseases. Immunoglobulin A (IgA) deficiency is the most common primary immunodeficiency and is defined as a decrease in serum IgA levels in the presence of normal levels of other immunoglobulin isotypes (1). Serum IgA deficiency was first described in children with ataxia-telangiectasia (2) and has since been identified in other patients, including normal patients. The prevalence of IgA deficiency ranges from 1:223 to 1:1000 in community studies and from 1:400 to 1:3000 in healthy blood donors (3).

Phase change materials are widely considered for application in nonvolatile memories because of their ability to achieve phase transformation in the nanosecond time scale. However, the knowledge of fast crystallization dynamics in these materials is limited because of the lack of fast and accurate temperature control methods. In this work, we have developed an experimental methodology that enables ultrafast characterization of phase-change dynamics on a more technologically relevant melt-quenched amorphous phase using practical device structures. We have extracted the crystallization growth velocity (U) in a functional capped phase change memory (PCM) device over 8 orders of magnitude (10(-10) < U < 10(-1) m/s) spanning a wide temperature range (415 < T < 580 K). We also observed direct evidence of non-Arrhenius crystallization behavior in programmed PCM devices at very high heating rates (>10(8) K/s), which reveals the extreme fragility of Ge2Sb2Te5 in its supercooled liquid phase. Furthermore, these crystallization properties were studied as a function of device programming cycles, and the results show degradation in the cell retention properties due to elemental segregation. The above experiments are enabled by the use of an on-chip fast heater and thermometer called as microthermal stage (MTS) integrated with a vertical phase change memory (PCM) cell. The temperature at the PCM layer can be controlled up to 600 K using MTS and with a thermal time constant of 800 ns, leading to heating rates ∼10(8) K/s that are close to the typical device operating conditions during PCM programming. The MTS allows us to independently control the electrical and thermal aspects of phase transformation (inseparable in a conventional PCM cell) and extract the temperature dependence of key material properties in real PCM devices.

In a 37 years-old female worker, who had undergone surgical excision of a segment of the right lower lobe for a chronic aspecific pleuropneumonitis, the histological examination of the excised lung tissue showed asbestos alveolitis with diffuse interstitial fibrosis, and multiple granulomata containing talc particles. An investigation at the work site showed that the worker had been engaged for 22 years in dusting salami with a mixture of rice flour and talc contaminated with chrysotile asbestos. Thirteen work-mates engaged in the same job were studied. In two of them, with chest X-rays negative for pneumoconiosis, a functional ventilatory impairment, restrictive in type, associated with a reduced pulmonary diffusion of gases, was demonstrated. In these two cases, bronchoalveolar lavage showed signs of severe exposure to asbestos (which at TEM evaluation resulted to be amphibolic) talc and other fibres, with presence of iron-laden macrophages, indicators of haemorrhagic alveolitis. Moreover, in one of them, a severe macrophagic-lymphocytic alveolitis, with inverted T helper/T suppressor ratio, was presented, possible expression of a hypersensitivity pulmonary reaction. Taking into consideration the length and modality of work, with exposure to talc powder contaminated with asbestos, for the three cases the diagnosis of "pre-radiologic talcosis-asbestosis" was made. Since the occupational risk was not known in this industry, no ambient and personal preventive and protective measures had been taken; anyway, such type of work has now been stopped. The exposed workers shall be kept under control in the future for surveillance directed towards early diagnosis of possible further asbestos effects.