Abstract
In this work, metamaterial-enabled ultra-compact evanescent-mode half-mode substrate integrated waveguide (HMSIW) bandpass filters are developed by loading inner-rotary complementary ...split-ring resonator (IRCSRR) on reinforced hydrocarbon polymer ceramic composites substrate. In the proposed IRCSRR, inner-rotary slots are etched inside the conventional complementary split-ring resonator (CSRR) metamaterials to enhance the product of equivalent inductance and capacitance without occupying extra circuit area. Therefore, the proposed HMSIW-IRCSRR filters can obtain more size reduction with the same operation frequency as compared with the conventional CSRR-based ones. Similar as the conventional CSRR case, the evanescent-mode transmission below the dominant cutoff frequency of HMSIW can be produced by the negative permittivity effect of IRCSRR, and a transmission zero (TZ) at the upper stopband can be simultaneously generated by the mutual coupling between HMSIW and IRCSRR. Then, to improve the upper stopband performance, source-load coupling topology is utilized in the two-pole filters, which can produce multiple extra TZs. Meanwhile, multiple microstrip L/T-shaped open stubs are employed to introduce hybrid low-pass effect to further extend the upper stopband much wider. To demonstrate the availability of the aforementioned concepts, a series of HSMIW-IRCSRR filters are experimentally designed, fabricated and verified. Measured results shows that both ultra-compact sizes and excellent frequency-selecting performance are achieved simultaneously, as well as good agreement with simulations, all of which illustrating quite good promises for the practical radio frequency and microwave applications.
Introduction: The available studies on extraction wound repair in humans are affected by significant limitations and have failed to evaluate tissue alterations occurring in all compartments of the ...hard tissue defect.
Aim: To monitor during a 6‐month period the healing of human extraction sockets and include a semi‐quantitative analysis of tissues and cell populations involved in various stages of the processes of modeling/remodeling.
Material and Methods: Twenty‐seven biopsies, representative of the early (2–4 weeks, n=10), intermediate (6–8 weeks, n=6), and late phase (12–24 weeks, n=11) of healing, were collected and analysed.
Results: Granulation tissue that was present in comparatively large amounts in the early healing phase of socket healing, was in the interval between the early and intermediate observation phase replaced with provisional matrix and woven bone. The density of vascular structures and macrophages slowly decreased from 2 to 4 weeks over time. The presence of osteoblasts peaked at 6–8 weeks and remained almost stable thereafter; a small number of osteoclasts were present in a few specimens at each observation interval.
Conclusions: The present findings demonstrated that great variability exists in man with respect to hard tissue formation within extraction sockets. Thus, whereas a provisional connective tissue consistently forms within the first weeks of healing, the interval during which mineralized bone is laid down is much less predictable.
Autism spectrum disorders (ASD) are a group of neurodevelopmental syndromes with both genetic and environmental origins. Several recent studies have shown that inflammation and oxidative stress may ...play a key role in supporting the pathogenesis and the severity of ASD. Thus, the administration of anti-inflammatory and antioxidant molecules may represent a promising strategy to counteract pathological behaviors in ASD patients. In the current review, results from recent literature showing how natural antioxidants may be beneficial in the context of ASD will be discussed. Interestingly, many antioxidant molecules available in nature show anti-inflammatory activity. Thus, after introducing ASD and the role of the vitamin E/vitamin C/glutathione network in scavenging intracellular reactive oxygen species (ROS) and the impairments observed with ASD, we discuss the concept of functional food and nutraceutical compounds. Furthermore, the effects of well-known nutraceutical compounds on ASD individuals and animal models of ASD are summarized. Finally, the importance of nutraceutical compounds as support therapy useful in reducing the symptoms in autistic people is discussed.
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•Altered social behavior is a pathological trait of autism spectrum disorder (ASD).•In mice, mutations in ASD genes result in altered social behavior.•Mouse models are a crucial tool ...to develop novel treatments for ASD.
Social behavior is evolutionary conserved, and is thought to be evolved since it increased reproductive and survival fitness of living species. In humans, disturbances of social behavior are a peculiar pathological trait of neurodevelopmental disorders, namely autism spectrum disorder (ASD). ASD is defined by deficits in two core domains (social interaction/communication and repetitive/restrictive behaviors), which emerge during early postnatal development. ASD has a strong genetic component: copy number variations, de novo and familial mutations, as well as epigenetic modifications have been reported in a huge number of genes. Recent studies in mice demonstrate that mutations in a wide variety of ASD-associated genes can cause neurodevelopmental defects, which subsequently result in social behavior disturbances during early postnatal age and adulthood. From these studies, it clearly emerges that functionally interrelated cellular mechanisms underlie social behavior and its disturbances in ASD. Indeed, most of ASD-associated genes control neuronal differentiation and migration, growth of neuronal connections and synaptic function. Here we will present the recent advances in understanding the genetic determinants of social behavior, as they emerge from the study of ASD mouse models, and discuss the importance of these studies for the development of novel therapeutic approaches to overcome social disturbances in ASD.
This letter presents an enhanced solution for low-cost sensors for the determination of the dielectric permittivity and the loss tangent of materials, based on substrate-integrated waveguide (SIW) ...cavities. The novelty consists in a slight, yet fundamental, modification of the standard sensor topology. The typical structure is based on an SIW resonant cavity with a hole in the middle and a pipe passing through, which contains the material under test. The modification consists in adding a metal sheath that partially covers the walls of the pipe. The metal sheath enhances the penetration of the electromagnetic field into the pipe, thus increasing the sensitivity of the device. Simulation and measurement results of various liquids demonstrate the advantage of the proposed structure.
Selecting the number of sensors to be actually used in acoustical signal beamformings that employ a given sensor array with a fixed number of elements is important for performance optimization in ...signal detection applications. Adding sensors to the beamforming computation might introduce excess noise into the measured signal, but selecting too few sensors reduces the beampattern resolution. Additionally, the sensor signals may be weighted to compensate for the background noise or known signal sources. In this paper, a maximum likelihood estimator is developed for the signal beamforming and the signal-to-noise ratio is used as a key performance indicator for determining the point at which adding sensors deteriorates the overall signal readout efficiency. As a case study, an experimental onshore passive sonar readout chain is analyzed through signal beamforming with a circular array with 32 sensors. The experimental results were supported by simulations and showed that the described method was able to calibrate the delay-and-sum algorithm for its best performance under noisy conditions. Good agreement has been obtained with a heuristic approximation from expert knowledge, and the method expands it to general applications.
In the present study, GeneSeek GGP-LDv4 33k single nucleotide polymorphism chip was used to detect runs of homozygosity (ROH) in eight Italian beef cattle breeds, six breeds with distribution limited ...to Tuscany (Calvana, Mucca Pisana, Pontremolese) or Sardinia (Sarda, Sardo Bruna and Sardo Modicana) and two cosmopolitan breeds (Charolais and Limousine). ROH detection analyses were used to estimate autozygosity and inbreeding and to identify genomic regions with high frequency of ROH, which might reflect selection signatures. Comparative analysis among breeds revealed differences in length and distribution of ROH and inbreeding levels. The Charolais, Limousine, Sarda, and Sardo Bruna breeds were found to have a high frequency of short ROH (~ 15.000); Calvana and Mucca Pisana presented also runs longer than 16 Mbp. The highest level of average genomic inbreeding was observed in Tuscan breeds, around 0.3, while Sardinian and cosmopolitan breeds showed values around 0.2. The population structure and genetic distances were analyzed through principal component and multidimensional scaling analyses, and resulted in a clear separation among the breeds, with clusters related to productive purposes. The frequency of ROH occurrence revealed eight breed-specific genomic regions where genes of potential selective and conservative interest are located (e.g. MYOG, CHI3L1, CHIT1 (BTA16), TIMELESS, APOF, OR10P1, OR6C4, OR2AP1, OR6C2, OR6C68, CACNG2 (BTA5), COL5A2 and COL3A1 (BTA2)). In all breeds, we found the largest proportion of homozygous by descent segments to be those that represent inbreeding events that occurred around 32 generations ago, with Tuscan breeds also having a significant proportion of segments relating to more recent inbreeding.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The variational meshless method (VMM) is a novel numerical algorithm that combines the intrinsic advantages of the meshless method based on the use of radial basis functions (RBFs) with the ...reliability of the variational formulation of electromagnetic boundary problems. It has been originally proposed and demonstrated in the analysis of 2-D structures, both homogeneous and inhomogeneous, aiming at the determination of the mode spectrum and the dispersion diagram. In this article, the VMM is extended to the calculation of the resonant modes of 3-D inhomogeneous cavities. The full theory is presented with implementation details. Moreover, the exploitation of symmetries is also discussed, which significantly speedup the method. Some examples are reported, and the results of the VMM are compared against either analytical values (when available) or commercial numerical codes based on the finite element method (FEM). In all cases, the VMM provides a large number of resonant modes with a limited number of unknowns, exhibiting high accuracy in short computing time.
In the seven years since the HIV Organ Policy Equity (HOPE) Act made HIV-positive organ donation to HIV-positive recipients legally permissible in the United States, there have been fewer ...HIV-positive organ donations than expected. Organ procurement organizations (OPOs) play a key role in the transplant system and barriers at OPOs may be partly responsible for the relatively low number of HIV-positive donors. To understand potential OPO barriers, we conducted semi-structured interviews with 20 OPO staff members. Interviews were recorded, transcribed, and analyzed using a conventional content analytic approach with two coders. OPO staff had high levels of knowledge about HOPE. Many had evaluated referrals of HIV-positive donors and approached families for authorization. Barriers to HIV-positive organ recovery identified included obtaining authorization for donation, potentially disclosing HIV status to next-of-kin, and fear of HIV infection among those engaged in organ recovery. Strategies to overcome these barriers include providing continuing education about the specific tasks required to procure organs from HIV-positive donors, implementing targeted interventions to reduce fear of infection, and developing partnerships with HIV advocacy and care organizations. Given the central role OPOs play, HIV-positive donations are unlikely to occur in significant numbers unless these barriers can be overcome.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, OILJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK, VSZLJ
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