Design and Analysis of a Fibre-Shaped Micro-Actuator for Robotic Gripping

A prototype of an automatic micropositioning system was developed. This prototype uses a shape memory alloy (SMA) actuator, a dedicated PI controller and a piece of software to command a desired motion profile for the actuator. The proposed micropositioning system is characterized by a 4 mm stroke, a 1 μm resolution and a 70 g nominal force and can be commanded directly from a personal computer and without human retroaction. The closed loop positioning resolution (1 μm) is obtained in spite of inaccurate system behaviour during its movement

A Novel Logic and Approach to Speed up Simulation and Analysis of Production Systems

The paper describes a novel logic to model, simulate and analyze production systems using Discrete Event Simulation tools. An adaptable and flexible DES model has been developed to represent different manufacturing environments. The goal of the proposed DES-based parametric model is to offer to industrial analysts a compact, fast and easy way to configure and use decision support tools. The logic is based on elementary structures with a vertical multilayer architecture that permits entities to access and loop in multiple times. Since it has been assumed manufacturing systems are combination of elementary parts, the architecture of the model becomes quite simple since representing few structures only, and the simulation of heterogeneous systems is the result of as many iterations as needed by a user. This approach is adaptable both to SMEs and large companies, permitting to avoid the use of dedicated SW and allocated skilled person

Embedded Payload Solutions in UAVs for Medium and Small Package Delivery

Investigations about the feasibility of delivery systems with unmanned aerial vehicles (UAVs) or drones have been recently expanded, owing to the exponential demand for goods to be delivered in the recent years, which has been further increased by the COVID-19 pandemic. UAV delivery can provide new contactless delivery strategies, in addition to applications for medical items, such as blood, medicines, or vaccines. The safe delivery of goods is paramount for such applications, which is facilitated if the payload is embedded in the main drone body. In this paper, we investigate payload solutions for medium and small package delivery (up to 5 kg) with a medium-sized UAV (maximum takeoff of less than 25 kg), focusing on (i) embedded solutions (packaging hosted in the drone fuselage), (ii) compatibility with transportation of medical items, and (iii) user-oriented design (usability and safety). We evaluate the design process for possible payload solutions, from an analysis of the package design (material selection, shape definition, and product industrialization) to package integration with the drone fuselage (possible solutions and comparison of quick-release systems). We present a prototype for an industrialized package, a right prism with an octagonal section made of high-performance double-wall cardboard, and introduce a set of concepts for a quick-release system, which are compared with a set of six functional parameters (mass, realization, accessibility, locking, protection, and resistance). Further analyses are already ongoing, with the aim of integrating monitoring and control capabilities into the package design to assess the condition of the delivered goods during transportation

TRH: Pathophysiologic and clinical implications

Thyrotropin releasing hormone is thought to be a tonic stimulator of the pituitary TSH secretion regulating the setpoint of the thyrotrophs to the suppressive effect of thyroid hormones. The peptide stimulates the release of normal and elevated prolactin. ACTH and GH may increase in response to exogenous TRH in pituitary ACTH and GH hypersecretion syndromes and in some extrapituitary diseases. The pathophysiological implications of extrahypothalamic TRH in humans are essentially unknown. The TSH response to TRH is nowadays widely used as a diganostic amplifier in thyroid diseases being suppressed in borderline and overt hyperthyroid states and increased in primary thyroid failure. In hypothyroid states of hypothalamic origin, TSH increases in response to exogenous TRH often with a delayed and/or exaggerated time course. But in patients with pituitary tumors and suprasellar extension TSH may also respond to TRH despite secondary hypothyroidism. This TSH increase may indicate a suprasellar cause for the secondary hypothyroidism, probably due to portal vessel occlusion. The TSH released in these cases is shown to be biologically inactive

Synthesis and gas-sensing properties of pd-doped SnO2 nanocrystals. A case study of a general methodology for doping metal oxide nanocrystals

Pd-modified SnO2 nanocrystals, with a Pd/Sn nominal atomic ratio of 0.025, were prepared by injecting SnO2 sols and a Pd precursor solution into tetradecene and dodecylamine at 160 degrees C. Two different doping procedures were investigated: in co-injection, a Pd acetylacetonate solution in chloroform was mixed with the SnO2 sol before the injection; in sequential injection, the Pd solution was injected separately after the SnO2 sol. The obtained suspensions were heated at the resulting 80 degrees C temperature, then the product was collected by centrifugation and dried at 80 degrees C. When using co-injection, in the dried products PdO and Pd nanoparticles were observed by high-resolution transmission electron microscopy. Only SnO2 nanocrystals were observed in dried products prepared by sequential injection. After heat-treatment at 500 degrees C, no Pd species were observed for both doping procedures. Moreover, X-ray photoelectron spectroscopy showed that, in both the doping procedures, after heat-treatment Pd is distributed only into the SnO2 nanocrystal structure. This conclusion was reinforced by the measurement of the electrical properties of Pd-doped nanocrystals, showing a remarkable increase of the electrical resistance if compared with pure SnO2 nanocrystals. This result was interpreted as Pd insertion as a dopant inside the cassiterite lattice of tin dioxide. The addition of Pd resulted in a remarkable improvement of the gas-sensing properties, allowing the detection of carbon monoxide concentrations below 50 ppm and of very low concentrations (below 25 ppm) of other reducing gases such as ethanol and acetone

Long-Term Outcomes of Diabetic Patients With Critical Limb Ischemia Followed in a Tertiary Referral Diabetic Foot Clinic

We describe the long-term outcomes of 510 diabetic patients with critical limb ischemia (CLI) and an active foot ulcer or gangrene, seen at the University Hospital of Rome Tor Vergata, a tertiary care clinic

Теоретико-методологічні основи розуміння механізму правового регулювання

Метою цієї статті є аналіз напрямів наукових досліджень, що у своїй єдності формують теорію механізму правового регулювання (МПР), розкриття теоретикометодологічних проблем, які мають місце при осмисленні МПР, визначення та систематизація методологічних підходів до розуміння МПР

Extensive use of peripheral angioplasty, particularly infrapopliteal, in the treatment of ischaemic diabetic foot ulcers : clinical results of a multicentric study of 221 consecutive diabetic subjects

OBJECTIVE: To evaluate the feasibility, technical effectiveness and limb salvage potential of percutaneous transluminal angioplasty (PTA), particularly infrapopliteal, in diabetic subjects with ischaemic foot ulcer. DESIGN: Intervention study with PTA in consecutive series. SETTING: Six Diabetology Foot Centres and one Cardiovascular Catheterization Laboratory in Italy. SUBJECTS: Two hundred and twenty-one consecutive diabetic subjects hospitalized for ischaemic foot ulcer. INTERVENTION: Peripheral arterial occlusive disease (PAOD) was investigated by means of foot pulses assessment, ankle-brachial-index (ABI), transcutaneous oxygen tension (TcPO2) and duplex scanning. If non-invasive parameters suggested PAOD, angiography was performed and a PTA was carried out during the same session. MAIN OUTCOME MEASURES: PTA feasibility, improvement of ABI and TcPO2, limb salvage rate, clinical recurrence. RESULTS: On angiography, two patients had stenoses which were 50%, even when longer than 10 cm and/or multiple/calcified. In 11 patients (5.8%) PTA was performed in the proximal axis exclusively, in 81 (42.4%) patients in the infrapopliteal axis exclusively and in 99 (51.8%) in both the femoropopliteal and infrapopliteal axis. Both ABI and TcPO2 improved significantly after PTA (P < 0.0001). Clinical recurrence occurred in 14 subjects: 10 of whom underwent a second successful PTA. Of the 191 patients who underwent PTA, 10 (5.2%) underwent an above-the-ankle amputation. CONCLUSIONS: PTA, including infrapopliteal, is feasible in most diabetic subjects with ischaemic foot ulcer and is effective for foot revascularization. Clinical recurrence was infrequent and the procedure could successfully be repeated in most cases. In subjects treated successfully with PTA the above-the-ankle amputation rate was low. PTA should be considered as the revascularization treatment of first choice in all diabetic subjects with foot ulcer and PAOD