1,673 research outputs found

    The Eneolithic/Bronze Age Transition at Tegole di Bovino (Apulia): Geoarchaeological Evidence of Climate Change and Land-Use Shift

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    Human communities at the transition between the Eneolithic period and the Bronze Age had to rapidly adapt to cultural and climatic changes, which influenced the whole Mediterranean. The exact dynamics involved in this crucial passage are still a matter of discussion. As newer studies have highlighted the key role of climatic fluctuations during this period, their relationship with the human occupation of the landscape are yet to be fully explored. We investigated the infilling of negative structures at the archaeological site of Tegole di Bovino (Apulia, Southern Italy) looking at evidence of the interaction between climate changes and human strategies. The archaeological sedimentary deposits, investigated though geoarchaeological and micromorphological techniques, show the presence of natural and anthropogenic infillings inside most structures. Both human intervention and/or natural events occurred in the last phases of occupation of the site and its subsequent abandonment. The transition to unfavorable climatic conditions in the same period was most likely involved in the abandonment of the site. The possible further impact of human communities on the landscape in that period, testified by multiple other archives, might have in turn had a role in the eventual change in land use

    The 3D-Printed Non-Radiating Edge Gap-Coupled Curved Patch Antenna

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    The use of parasitic resonant patches is a widespread technique to improve the bandwidth of microstrip patch antennas. Exploiting the free form-factor allowed by 3D-printing manufacturing technology, we present here a novel curved patch antenna layout, based on the non-radiating edge gap-coupled patch configuration. The proposed antenna is composed of a central curved patch, fed by a coaxial probe, and two gap-coupled parasitic side curved patches. This solution features a percentage impedance bandwidth of 16.3% using symmetrical parasitic side patches and 31.5% using asymmetrical side patches. A significant improvement of the bandwidth in comparison with both the standard non-radiating edge gap-coupled microstrip antenna (6.1% bandwidth) and the standard curved patch antenna (9% bandwidth) is achieved. Design and optimization of the proposed configuration are performed using the commercial software CST Studio Suite at the center frequency of 2.45 GHz. Prototypes of the symmetrical curved non-radiating edge gap-coupled patch antenna have been manufactured for the experimental verification, using a curved 3D-printed polylactic acid (PLA) substrate, fabricated with the commercial 3D printer PRUSA MK3S + and a 50 μ m -thick adhesive aluminum tape for the metallization. Measured results show a very good agreement with simulations

    A Novel Design for Dual-Band Wearable Textile Eighth-Mode SIW Antennas

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    A novel wearable textile dual-band antenna configuration based on a substrate integrated waveguide (SIW) cavity is presented. The miniaturization of the antenna is achieved by exploiting the magnetic field symmetry of a square SIW cavity, reducing its size to 1/8 of the full square cavity with an eighth-mode SIW configuration. This solution is applied to the design of a wearable dual-band antenna for Long Range (LoRa) applications. The antenna operating frequency covers both the UHF LoRa bands, the European (863-870 MHz) and the North American (902-928 MHz). The proposed design provides a low-cost and compact antenna, which is easy to fabricate and ensures a very good isolation and robustness with respect to the human body proximity. The commercial software CST Studio Suite has been used for the antenna design and simulations. A prototype has been fabricated and the measured results are in good agreement with numerical simulations

    A Compact and Robust RFID Tag Based on an AMC Structure

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    A platform-tolerant RFID (Radio-Frequency Identification) tag is presented, designed to operate across the entire RFID band. This tag utilizes a small Artificial Magnetic Conductor (AMC) structure as a shielding element for an ungrounded RFID tag antenna. It can be easily mounted on various surfaces, including low permittivity dielectric materials, metal objects, or even attached to the human body for wearable applications. The key features of this RFID tag include its ability to be tuned within the worldwide RFID band, achieving a maximum theoretical read range of over 11 m. Despite its advanced capabilities, the design emphasizes simplicity and cost-effective manufacturing. The design and simulations were conducted using CST Studio Suite

    A Wideband Single-Feed Circularly Polarized Stacked Patch Antenna

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    We present a circularly polarized single-feed stacked patch antenna with wide axial ratio bandwidth, suitable for both coaxial probe feeding and coplanar microstrip feeding. The antenna is composed of two patches with truncated corners connected together using four pins. The circularly polarized antenna has been designed using CST Studio Suite in the upper part of the UHF frequency band. A prototype has been fabricated using low-cost 3D-printing manufacturing technology. In this regard, both the dielectric substrate and the support for the stacked patches have been realized with a 3D-printed Polylactic Acid. Measured results provide a 34% -10 dB reflection coefficient bandwidth (between 2.14 and 3.03 GHz) and a 3 dB axial ratio bandwidth of 25% (between 2.31 and 2.97 GHz), with a flat gain in the overlapped (axial ratio-reflection coefficient) bandwidth that coincides with the axial ratio bandwidth and a peak gain of 8.5 dBic

    A Low-Cost Printed Log-Periodic Dipole Array for DVB-T2 Digital TV Applications

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    A printed log-periodic dipole array (LPDA) for DVB-T2 Digital TV applications, covering the whole DVB-T2 UHF band from Channel 21 to Channel 69 (470 MHz–860 MHz), is presented. The presented antenna offers a compact size and a lower cost compared to both wire and similar printed LPDAs, with a normalized area of only 0.26 λ2 (where λ is the free-space wavelength at the central frequency) and a similar (or higher) average gain. It is composed of meandered radiating dipoles, and it is implemented on FR4, the cheapest dielectric substrate available on the market. Moreover, the antenna size has been reduced to an A4 sheet dimension (210 mm × 297 mm) to cut down the production cost. The antenna has been designed starting from Carrel’s theory and using a general-purpose 3D CAD, CST Studio Suite. The results show that the proposed antenna can be used for broadband applications (≈74% bandwidth) in the whole operating frequency band of Digital TV, with a satisfactory end-fire radiation pattern, a stable gain, and a radiation efficiency over the required frequency range (average values 6.56 dB and 97%, respectively)

    The NorthStar Ambulatory Assessment in Duchenne muscular dystrophy: considerations for the design of clinical trials.

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    With the emergence of experimental therapies for Duchenne muscular dystrophy (DMD), it is fundamental to understand the natural history of this disorder to properly design clinical trials. The aims of this study were to assess the effects produced on motor function by different DMD genotypes and early initiation of glucocorticoids

    Cannabinoids and their therapeutic applications in mental disorders

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    Mental disorders represent a significant public health burden worldwide due to their high prevalence, chronically disabling nature, and substantial impact on quality of life. Despite growing knowledge of the pathological mechanisms that underlie the development of these disorders, a high percentage of patients do not respond to first-line clinical treatments; thus, there is a strong need for alternative therapeutic approaches. During the past half-century, after the identification of the endocannabinoid system and its role in multiple physiological processes, both natural and synthetic cannabinoids have attracted considerable interest as putative medications in pathological conditions such as, but not exclusive to, mental disorders. Here, we provide a summary of cannabinoid effects in support of possible therapeutic applications for major depression, bipolar disorder, anxiety, posttraumatic stress disorder, and schizophrenia. Considering this evidence, highlighted benefits and risks of cannabinoid use in the management of these illnesses require further experimental study
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