Miracle-dz/UniFAR-FTUs huggingface dataset:
LOSS MECHANISMS IN PIEZOELECTRIC PZT CERAMICS AND SINGLE CRYSTALS

This thesis aims to clarify the loss mechanisms in piezoelectric ceramics and single crystals in the view of the recent developments in high power piezoelectric devices such as piezoelectric actuators, ultrasonic motors and piezoelectric transformers in commercial applications. In these devices the piezoelectric materials are driven under high voltages and currents. At high power conditions, the materials deviate from their linear constitutive equations due to non-linearity and hysteresis in physical parameters. The non-linearity and hysteresis manifests in terms of loss and consequently, heat generation in piezoelectric materials. Therefore, analysis of the fundamental principles of loss mechanisms is essential in the determination of heat generation. The loss in piezoelectric materials is directly related to the mechanical quality factor which is defined as the inverse of the loss tangent factor. The quality factor is experimentally calculated following IEEE standards using the impedance curves, Qm as well as near resonance and anti-resonance frequencies and defined as QA and QB. The low power measurement setup in terms of sample holders is reexamined in order to obtain reproducible results. Loss in the 33- and 31- vibration modes is clarified for ‘hard’ and ‘soft’ piezoelectric PZT ceramics. Further loss anisotropy in PMN-PT based single crystals as a function of crystal orientation dependence, vibration mode and doping is investigated. Losses associated with resonance and anti-resonance modes are discussed in the above materials. Significant difference (20-40%) between Q values at resonance (QA) and anti-resonance (QB) with Q being higher for anti-resonance mode. This result is verified analytically and dependence of the quality factor on k31 (electromechanical coupling coefficient), tanδ’ (dielectric loss), tanϕ’(mechanical loss) and tanθ’ (piezoelectric loss) is observed. Quality factors (QA and QB) are also calculated at high power near resonance and anti-resonance while maintaining the vibration velocity constant in order to observe the difference at ‘in-service’ conditions. At high power the quality factors drop by almost half as compared to the low power characterization while maintaining the difference in QA and QB seen at low power. Based on these results it is recommended to drive piezoelectric devices at anti-resonance mode in order to get better efficiency.
Calibration of Hypoplastic Models for Soils

The paper is concerned with hypoplastic models for both coarse and fine grained soils. It concentrates on the description of models parameters and presents procedures for their evaluation based on actual laboratory tests. The sample of sand for the calibration of the hypoplastic model for coarse grained soil comes from the Třeboň basin. The sample was classified as Sa. The second sample was classified as saCl. This sample comes from the street Evropská in Prague and was used for the calibration of the hypoplastic model for fine grained soils. The classification was performed according to ČSN EN ISO 14688-2. Keywords: hypoplasticity, fine grained soils, coarse grained soils, calibration, parameters.
QoS assurance with colocated wireless access points

The proposed research aims to provide the technical framework which will enable multiple Wireless LANs to provide the assured network service while being in communication range of each other. The Access Points involved compete and cooperate while keeping the overall goal of maximum system utilization above individual optimization. We use channel access time as the means of resource allocation, while keeping the system modular so that any other unit can also be used without changing the protocol. We provide a secondary protocol to ensure robustness of our main algorithm for Access Allocation. We also propose a model to measure Transport Level Goodput with the help of MAC level parameters. In turn, we also derive MAC level performance in terms of the physical environment characteristics such as number of other stations, APs and their clients. Although simple estimates based on current Internet conditions can be made already, our work helps us estimate the performance which can be assured to clients with a much higher accuracy. This result can be independently applied to model the performance of any wireless network. Thesis Supervisor: John T. Wroclawski Title: Research Scientist
Recent Developments in Carbon-Based Nanocomposites for Fuel Cell Applications: A Review

Carbon-based nanocomposites have developed as the most promising and emerging materials in nanoscience and technology during the last several years. They are microscopic materials that range in size from 1 to 100 nanometers. They may be distinguished from bulk materials by their size, shape, increased surface-to-volume ratio, and unique physical and chemical characteristics. Carbon nanocomposite matrixes are often created by combining more than two distinct solid phase types. The nanocomposites that were constructed exhibit unique properties, such as significantly enhanced toughness, mechanical strength, and thermal/electrochemical conductivity. As a result of these advantages, nanocomposites have been used in a variety of applications, including catalysts, electrochemical sensors, biosensors, and energy storage devices, among others. This study focuses on the usage of several forms of carbon nanomaterials, such as carbon aerogels, carbon nanofibers, graphene, carbon nanotubes, and fullerenes, in the development of hydrogen fuel cells. These fuel cells have been successfully employed in numerous commercial sectors in recent years, notably in the car industry, due to their cost-effectiveness, eco-friendliness, and long-cyclic durability. Further; we discuss the principles, reaction mechanisms, and cyclic stability of the fuel cells and also new strategies and future challenges related to the development of viable fuel cells.
Forever Flash

In the world of memory chips, flash is king. But it's not perfect. It wears out after being programmed and erased about 10 000 times. That's fine for a USB dongle that you'll probably lose in a year, but not ideal for the solid-state drives of server farms. And the same problem keeps manufacturers from using flash to replace other types of computer memories. This month, at the 2012 IEEE International Electron Devices Meeting, engineers from Macronix plan to report the invention of a self-healing NAND flash memory that survives more than 100 million cycles.
An exploratory study of the relationship between motor skills and indicators of cognitive and socio-emotional development in preschoolers

ABSTRACT Motor skills develop rapidly during early childhood and are considered important for optimal child development. However, little is known about the relationship of motor skills with indicators of cognitive and socio-emotional development in typically developing preschoolers. In view of this, the present study examined the association of gross motor and fine motor skills with executive functions and prosocial behaviour in preschoolers. The study sample consisted of 111 participants between 3 and 5 years of age, who were assessed using the short version of the Bruininks-Oseretsky Test of Motor Proficiency, second edition (BOT-2); the head-toes-knees-shoulders task; the Corsi block-tapping test (CBTT); the dimensional change card sort test (DCCS); and a teacher-rated prosocial behaviour questionnaire (PBQ). The results revealed significant positive associations between motor skills and executive functions as well as prosocial behaviour. Specifically, fine motor skills were twice as strong as a predictor for response inhibition compared to gross motor skills whereas gross motor skills dominated over fine motor skills in predicting prosocial behaviour. The findings of the study highlight the need to promote motor skills during early years of development.
Real-time object detector for low-end devices

Abstract. YOLOv4-tiny is a lightweight network designed for low-end devices. It proposes a global model scaling technology, which uses the same scaling method with few convolution filters in each stage of the network, resulting in a small receptive field and low accuracy. To solve this problem, we use different scaling techniques in shallow and deep network stages. For the shallow network stage, the Simple-StemBlock scaling module is proposed to simplify network based on factors such as FLOPs and network fragmentation. The module can effectively reduce computation and improve the diversity of features. For the deep network stage, we consider depth of network and hardware resource constraints, the Depth-CSPBlock scaling module is designed to expand receptive field while keeping the computation as low as possible and layered residual connection is built in the module to enrich semantic information. Besides, mish activation function is adopted in the backbone for higher accuracy. The experimental results show that the accuracy of the proposed method achieves 23.2% AP on MSCOCO test-dev and 66.73 % AP50 on VOC datasets, compared with YOLOv4-tiny, the AP and AP50 increased by 3.3% and 3.7%, respectively. The speed of the proposed method on Jetson TX2 can reach 45.6 frames per second, which is 20% faster than YOLOv4-tiny.
Gender Differences in Demographic and Pharmacological Factors in Patients Diagnosed with Late-Onset of Alzheimer’s Disease

Background: Whether gender differences exist in late-onset of Alzheimer’s disease (LOAD) treated with cholinesterase inhibitors (ChEIs) is not fully understood. This study investigated demographic and pharmacological characteristics in LOAD patients to determine gender differences in LOAD patients treated with ChEIs alone and ChEIs with other medications. Methods: This 5-year retrospective data analysis included 9290 LOAD AD patients with 2949 men patients and 6341 women. Potential predictors of demographic and pharmacological characteristics associated gender differences in patients treated with and without ChEIs therapy were determined using univariate analysis, while multivariable models adjusted for demographic and pharmacological variables. Results: In the adjusted analysis, men patients with LOAD that presented with a history of alcohol use (ETOH) (OR = 1.339, 95% CI, 1.072–1.672, p = 0.010), treated with second generation antipsychotics (SGAs) (OR = 1.271, 95% CI, 1.003–1.610, p = 0.047), citalopram (OR = 5.103, 95% CI, 3.423–7.607, p < 0.001), memantine (OR = 4.409, 95% CI, 3.704–5.249, p < 0.001), and buspirone (OR = 2.166, 95% CI, 1.437–3.264, p < 0.001) were more likely to receive ChEIs therapy, whereas older men were less likely to be treated with ChEIs therapy. Women who were African Americans (OR = 1.387, 95% CI, 1.168–1.647, p < 0.001), that received memantine (OR = 3.412, 95% CI, 3.034–3.837, p < 0.001), selective serotonin reuptake inhibitor (SSRIs) (OR = 1.143, 95% CI, 1.016–1.287, p = 0.026), and a history of ETOH (OR = 2.109, 95% CI, 1.724–2.580, p < 0.001) were more likely to receive ChEIs therapy, whereas older women were less likely to receive ChEIs therapy. Conclusion: In both men and women patients, those with increasing age were less likely to be treated with ChEI therapy, while patients treated with memantine were also likely to receive ChEI therapy. Our findings highlight the importance for clinicians to optimize ChEI in LOAD to improve treatment effectiveness and eliminate gender differences in ChEI therapy.
Systematic Review for the Medical Applications of Meditation in Randomized Controlled Trials

Background: Meditation has been increasingly adapted for healthy populations and participants with diseases. Its beneficial effects are still challenging to determine due to the heterogeneity and methodological obstacles regarding medical applications. This study aimed to integrate the features of therapeutic meditation in randomized controlled trials (RCTs). Methods: We conducted a systematic review of RCTs with meditation for populations with diseases using the PubMed database through June 2021. We analyzed the characteristics of the diseases/disorders, participants, measurements, and their overall benefits. Results: Among a total of 4855 references, 104 RCTs were determined and mainly applied mindfulness-based (51 RCTs), yoga-based (32 RCTs), and transcendental meditation (14 RCTs) to 10,139 patient-participants. These RCTs were conducted for participants with a total of 45 kinds of disorders; the most frequent being cancer, followed by musculoskeletal and connective tissue diseases and affective mood disorder. Seven symptoms or signs were frequently assessed: depressive mood, feeling anxious, quality of life, stress, sleep, pain, and fatigue. The RCTs showed a higher ratio of positive outcomes for sleep (73.9%) and fatigue (68.4%). Conclusions: This systematic review produced the comprehensive features of RCTs for therapeutic meditation. These results will help physicians and researchers further study clinical adaptations in the future as reference data.
TOTAL BACTERIAL COUNT, SOMATIC CELL COUNT AND PRESENCE OF AFLATOXIN M1 IN RAW MILK FROM THE “OVČE POLE” REGION, REPUBLIC OF NORTH MACEDONIA

Dairy product quality monitoring begins at the farm and ends in the hands of the consumer. Raw milk must also meet other quality standards; it should be free of drug residues, free of added water and free of sediment, contaminants and other abnormalities. In our researches, is taken somatic cells count, the number of bacteria and Aflatoxins as indicators of the quality of raw milk from the Ovče Pole region in the period January-June, 2018. For the needs of this research, an analysis was made of 1320 samples for the presence of bacteria in raw milk, determination of somatic cell count in 478 samples as well as identification and quantification of aflatoxin M1 in 60 samples. The results from this study indicated determination acceptable count of somatic cells in 95.5 % of the samples from raw milk while in 2 samples of raw milk, the amount of aflatoxin M1 was above limits with highest amount of 0.58 mg/kg raw milk. According to European milk quality standards, in the biggest part of the samples (89.55 %), presence of bacteria does not meet the standard. From the analyses made by the milk producers that were the subject of analysis in this research, it can be concluded that they do not adhere to good agricultural practice, the level of milk contamination is high due to poor hygiene, improper handling of milk after milking and insufficient education of farmers for hygiene in primary production
Supplementary material to "Enhancing disaster risk resilience using greenspace in urbanising Quito, Ecuador"

Abstract. Greenspaces within broader ecosystem-based disaster risk reduction strategies (Eco-DRR) provide multiple benefits to society, biodiversity, and addressing climate breakdown. In this study, we investigated urban growth, its intersection with hazards, and the availability of greenspace for disaster risk reduction (DRR) in the city of Quito, Ecuador, which experiences multiple hazards including landslides, floods, volcanoes, and earthquakes. We used satellite data to quantify urban sprawl and developed a workflow incorporating high resolution digital elevation models (DEMs) to identify potential greenspaces for emergency refuge accommodation (DRR greenspace), for example following an earthquake. Quito’s historical urban growth totalled ~192 km2 1986–2020 and was primarily on flatter land crossed by deep ravines. By contrast, future projections indicate an increasing intersection between easterly urbanisation and steep areas of high landslide susceptibility. Therefore, a timely opportunity exists for future risk-informed planning. Our workflow identified 18.6 km2 of DRR greenspaces, of which 16.3 km2 intersected with potential sources of landslide and flood hazards, indicating that hazard events could impact potential ‘safe spaces’. These spaces could mitigate future risk if designated as greenspaces and left undeveloped. DRR greenspace overlapped 7 % (2.5 km2) with municipality designated greenspace. Similarly, 10 % (1.7 km2) of municipality designated ‘safe space’ for use following an earthquake was classified as potentially DRR suitable in our analysis. For emergency refuge, currently designated greenspaces could accommodate ~2–14 % of Quito’s population within 800 m. This increases to 8–40 % considering all the potential DRR greenspace mapped in this study. Therefore, a gap exists between the provision of DRR and designated greenspace. Within Quito, we found a disparity between access to greenspaces across socio-economic groups with lower income groups having less access and further to travel to designated greenspaces. Notably, the accessibility of greenspaces was high overall with 98 % (2.3 million) of Quito’s population within 800 m of a designated greenspace, of which 88 % (2.1 million) had access to potential DRR greenspaces. Our workflow demonstrates a citywide evaluation of DRR greenspace potential and provides the foundation upon which to evaluate these spaces with local stakeholders. Promoting equitable access to greenspaces, communicating their multiple benefits, and considering their use to restrict propagating development into hazardous areas are key themes that emerge for further investigation.
Neutrophils, Cancer and Thrombosis: The New Bermuda Triangle in Cancer Research

Spontaneous venous thrombosis is often the first clinical sign of cancer, and it is linked to a worsened survival rate. Traditionally, tumor-cell induced platelet activation has been the main actor studied in cancer-associated-thrombosis. However, platelet involvement alone does not seem to be sufficient to explain this heightened pro-thrombotic state. Neutrophils are emerging as key players in both thrombus generation and cancer progression. Neutrophils can impact thrombosis through the release of pro-inflammatory cytokines and expression of molecules like P-selectin and Tissue Factor (TF) on their membrane and on neutrophil-derived microvesicles. Their role in cancer progression is evidenced by the fact that patients with high blood-neutrophil counts have a worsened prognosis. Tumors can attract neutrophils to the cancer site via pro-inflammatory cytokine secretions and induce a switch to pro-tumoral (or N2) neutrophils, which support metastatic spread and have an immunosuppressive role. They can also expel their nuclear contents to entrap pathogens forming Neutrophil Extracellular Traps (NETs) and can also capture coagulation factors, enhancing the thrombus formation. These NETs are also known to have pro-tumoral effects by supporting the metastatic process. Here, we strived to do a comprehensive literature review of the role of neutrophils as drivers of both cancer-associated thrombosis (CAT) and cancer progression.
Characterization and Evaluation of Antioxidant and Anti-Inflammatory Activities of Flavonoids from the Fruits of Lycium barbarum

The fruits of Lycium barbarum are rich in flavonoids, which may contribute to the health-promoting function of Lycium barbarum. However, the composition of flavonoids in the fruits of Lycium barbarum (LBFs) has received little attention. Thus, the goal of this work was to identify more kinds of flavonoids from fruits of Lycium barbarum by liquid chromatography–mass spectrometry. The potential antioxidant and anti-inflammatory activities of LBFs in vitro were also investigated. Thirteen flavonoid compounds were identified in LBFs, of which daphnetin, 6,7-dihydroxycoumarin, astragalin, taxifolin, eriodictyol, naringenin, and chrysoeriol were identified for the first time in the fruits of Lycium barbarum, which greatly enriched the variety of flavonoids in the fruits of Lycium barbarum. LBFs showed a similar superior antioxidant activity to vitamin C. Furthermore, LBFs exhibited an anti-inflammatory activity by suppressing the production of nitric oxide and pro-inflammatory cytokines, including tumor necrosis factor-alpha, interleukin-1β, and interleukin-6, in lipopolysaccharide-treated RAW264.7 macrophage cells. This study demonstrated the potential development of LBFs as functional foods.
Large- and Small-Fiber Neuropathy in Patients with Tarlov Cysts

Purpose Tarlov cysts (TCs) are dilated nerve root sheaths originating from increased cerebrospinal pressure. Patients with TCs often complain of neuropathic pain and paresthesia. The aim of this study was to retrospectively review intraepidermal nerve fiber density (IENFD) and electrodiagnostic (EDX) data from TC patients. Patients and Methods Lower leg skin biopsy results and EDX data from the L2–S4 myotomes of patients with lumbar or sacral TCs ≥8 mm were retrieved from a database of a physical medicine clinic. Patients with compressive pathology, diabetes mellitus and chemotherapy were excluded. Results IENFD data from 17 patients and EDX data from 24 patients with TCs ≥8 mm were available. The mean age was 47 ± 10y, and 83% were women. In 82% of patients, the IENFD was below the 5th percentile by age and sex. EDX showed increased Hoffmann reflex latencies in 25%, increased anal reflex latencies in 95%, and a patchy distribution of neurogenic motor unit potentials in 100%. More than 50% of needle EMG abnormalities appeared in myotomes unrelated to the location of the TCs. Conclusion Small- and/or large-fiber neuropathy was documented in a significant proportion of patients with TCs. The novel findings may add to the understanding of the mechanisms involved in symptomatic TCs. We propose that pathologically elevated cerebrospinal fluid pressure not only dilates some of the nerve root sheaths to form TCs but also potentially damages axons in nondilated nerve root sheaths and neurons in the dorsal root ganglia.
Assessing the relationship between gamified advertising and in-app purchases: a consumers’ benefits-based perspective

Abstract Purchase through mobile apps (m-commerce) is on the rise. While this phenomenon is affecting any consumers cohort, millennials represent the lion’s share among m-commerce users. Businesses are anyway struggling to better obtain the attention of a younger consumers. Indeed, the more competitors start to use m-commerce, the more differentiating communication strategies get difficult. To continue to attract the consideration from younger consumers, marketers are therefore adopting gamification as a strategic marketing lever. Thus, gamified advertisings -which are advertising characterized by high interactivity and game-like features- are becoming a trending topic in marketing literature. Building on Use and Gratification Theory (UGT) and Theory of Planned Behavior (TPB), the research wishes to explore how consumers’ experience deriving from Gamified Advertising (GAMEX) could contribute to the creation of consumers’ benefits and their intention to purchase trough a mobile app. How gamification experience could correspondingly shape the attitude toward advertising has also been considered. To achieve the aim of the research, a structural model was tested trough data collected from 315 millennials living in the UK. Results show how a relationship between gamification induced experiences could foster in-app purchases. Anyway, such a connection is mediated by perceived consumer-benefits, their attitude toward advertising, and perceived advertising effectiveness. Gamified advertising thus can be effective if it could foster social, personal, hedonic and cognitive benefits, and whether gamification is perceived coherent with the advertised product/brand pair.
A Review of the Enterprise Theory: Formation, Essence, Boundary and Goal

Based on the formation, essence, boundary and goal of different enterprise theories as the review object, this paper reviews the enterprise theory of neoclassical economics. It is the four mainstream schools of enterprise contract theory and the enterprise theory of stakeholder collective choice. Additionally, it includes a brief and pertinent evaluation and comparison of these views.