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Ochratoxin A (OTA) is a toxic secondary metabolite produced by the Aspergillus species which can contaminate various food products. This study analysed the transcriptome of the Aspergillus westerdijkiae fc-1 strain under NaCl concentrations of 0, 20, and 100 g/L using RNA-Seq technology to examine gene transcriptional changes linked to osmotic stress and OTA production. Significant changes were observed in metabolic-pathways associated with carbohydrates, cellular communication, and hydrolase activity under 20 g/L NaCl. The HOG1 gene, associated with osmotic pressure regulation was down-regulated by 78.06%. In contrast, OTA biosynthesis genes otaA, otaB, and otaC were up-regulated by 3.26 fold, 1.99 fold, and 2.06 fold, respectively. Conversely, the otaD gene was down-regulated by 43.50%. At 100 g/L NaCl, pathways related to ion transport, peptide metabolism, ribosomal function, and transmembrane transporter protein activities were significantly up-regulated. The HOG1 gene was up-regulated by 28.32% and OTA biosynthesis genes otaA, otaB, otaC, and otaD showed up-regulation of 27.06%, 36.80%, 19.59%, and 5.72 fold, respectively. The study highlights the role of metabolic pathways in osmotic stress regulation and the correlations between HOG1 expression and OTA biosynthesis genes, providing insights for developing strategies to prevent OTA contamination in food. [ABSTRACT FROM AUTHOR]

As the number of 5G NR base stations increases, the demand for performance testing of base stations also increases. However, many 5G base stations are installed in locations where direct measurements are impossible. Accordingly, base station performance testing should be switched from direct measurements to OTA. When conducting base station performance testing of OTA, interference from adjacent signals should be considered, unlike direct measurements, unless it is shielded. In Korea, the output frequencies of the 5G NR base stations of all three companies (LG U+, KT, and SKT) are located adjacent to each other. In this case, the signal performance measurement of adjacent bands is impossible. This paper proposes a method to solve the interference problem by excluding it from the measurement of other service signals by utilizing the signal characteristics of 5G NR. It confirms that the performance measurement presented in 3GPP can be replaced by OTA measurement. [ABSTRACT FROM AUTHOR]

An approach to design analog building blocks based on digital standard cells is presented in this work. By ensuring that every CMOS inverter from a standard-cell library operates with a well-defined quiescent current and output voltage, the suggested method makes it possible to construct analog circuits that are resistant against PVT variations. The method uses the local supply voltages connected to the source terminals of the p-channel and n-channel MOS transistors of the standard-cell inverters as control inputs. It is based on adaptive supply voltage generator (ASVG) reusable blocks, which are comparable to those used in digital applications to handle process variations. All of the standard-cell inverters used for analog functions receive the local supply voltages produced by the ASVGs, which enable setting each cell's quiescent current to a multiple of a reference current and each cell's static output voltage to an appropriate reference voltage. Both the complete custom design of the ASVG blocks and a theoretical study of the feedback loop of the ASVG are presented. An application example through the design of a fully synthesizable two-stage operational transconductance amplifier (OTA) is also provided. The TSMC 180 nm CMOS technology has been used to implement both the OTA and the ASV generators. Simulation results have demonstrated that the proposed approach allows to accurately set the quiescent current of standard-cell inverters, dramatically reducing the effect of PVT variations on the pmain performance parameters of the standard-cell-based two-stage OTA. [ABSTRACT FROM AUTHOR]

In this paper, a rail-to-rail transconductance stable and enhanced ultra-low-voltage operational transconductance amplifier (OTA) is proposed for electrocardiogram (ECG) signal processing. The variation regularity of the bulk transconductance of pMOS and nMOS transistors and the cancellation mechanism of two types of transconductance variations are revealed. On this basis, a transconductance stabilization and enhancement technique is proposed. By using the "current-reused and transconductance-boosted complementary bulk-driven pseudo-differential pairs" structure, the bulk-driven pseudo-differential pair during the input common-mode range (ICMR) is stabilized and enhanced. The proposed OTA based on this technology is simulated using the TSMC 0.18 μm process in a Cadence environment. The proposed OTA consumes a power below 30 nW at a 0.4 V voltage supply with a DC gain of 54.9 dB and a gain-bandwidth product (GBW) of 14.4 kHz under a 15 pF capacitance load. The OTA has a high small signal figure-of-merit (FoM) of 7410 and excellent common-mode voltage (VCM) stability, with a transconductance variation of about 1.35%. Based on a current-scaling version of the proposed OTA, an OTA-C low-pass filter (LPF) for ECG signal processing with VCM stability is built and simulated. With a −3 dB bandwidth of 250 Hz and a power consumption of 20.23 nW, the filter achieves a FoM of 3.41 × 10−13, demonstrating good performance. [ABSTRACT FROM AUTHOR]

Ochratoxin A (OTA) is a toxic secondary metabolite produced by the Aspergillus species which can contaminate various food products. This study analysed the transcriptome of the Aspergillus westerdijkiae fc-1 strain under NaCl concentrations of 0, 20, and 100 g/L using RNA-Seq technology to examine gene transcriptional changes linked to osmotic stress and OTA production. Significant changes were observed in metabolic-pathways associated with carbohydrates, cellular communication, and hydrolase activity under 20 g/L NaCl. The HOG1 gene, associated with osmotic pressure regulation was down-regulated by 78.06%. In contrast, OTA biosynthesis genes otaA, otaB, and otaC were up-regulated by 3.26 fold, 1.99 fold, and 2.06 fold, respectively. Conversely, the otaD gene was down-regulated by 43.50%. At 100 g/L NaCl, pathways related to ion transport, peptide metabolism, ribosomal function, and transmembrane transporter protein activities were significantly up-regulated. The HOG1 gene was up-regulated by 28.32% and OTA biosynthesis genes otaA, otaB, otaC, and otaD showed up-regulation of 27.06%, 36.80%, 19.59%, and 5.72 fold, respectively. The study highlights the role of metabolic pathways in osmotic stress regulation and the correlations between HOG1 expression and OTA biosynthesis genes, providing insights for developing strategies to prevent OTA contamination in food.

A four‐stage CMOS operational amplifier is proposed in this work. The designed amplifier is frequency compensated via two differential blocks and two Miller capacitors. Unlike well‐known frequency compensation methods, the proposed compensation leaves the output node while exploiting extremely smaller capacitors compared to conventional approaches. The presented approach is modeled symbolically and realized at the circuit level via the Hspice circuit simulator and 0.18 μm CMOS technology. Good agreements between two separate simulation paths verify the validity and accuracy of the proposed approach. Ample simulation results are reported to investigate the proposed amplifier regarding parameter mismatches. According to the simulation results, the proposed four‐stage amplifier is an excellent candidate to be used in larger systems such as data converters, modulators, and sensors while it shows more than 169 dB as DC‐gain, 10 MHz as unity gain frequency with power consumption less than 500 μW. [ABSTRACT FROM AUTHOR]

In this paper, two floating memcapacitor emulator circuits, one based on a second-generation current conveyor (CCII) and the other on an operational transconductance amplifier (OTA), are proposed. The first floating memcapacitor contains a single CCII, one multiplier, and four transistors, while the second one comprises a single OTA, one multiplier, and only two transistors. External transistors are operated as electronically controllable grounded capacitors and resistors. Therefore, the inverse memcapacitances of the circuits are adjusted electronically by applying appropriate bias voltages. Both emulator circuits can be operated to have incremental or decremental characteristics. The analyses of frequency response, electronic adjustability, temperature behavior, and non-volatile behavior of the circuits, as well as Monte Carlo analysis, are performed. Furthermore, an adaptive learning circuit is utilized to demonstrate the applicability of the proposed memcapacitor. Additionally, the CCII-based emulator circuit is constructed on a printed circuit board using discrete circuit elements and tested experimentally. The non-volatility feature of the circuit was tested for both incremental and decremental memcapacitors. The simulation and experimental results agree with the expected results. [ABSTRACT FROM AUTHOR]

The growing need for high-performance folded cascode CMOS OTAs in various fields, such as electronics and communications, requires them to operate with wide bandwidth, high voltage gain, compact devices, and low power consumption. Recent research indicates that implementing the water cycle algorithm (WCA) can greatly improve the performance of the folded cascode CMOS operational transconductance amplifier (OTA). This is due to the WCA's ability to perform both global search and local exploration efficiently. Notably, the OTA in question is constructed using 0.18µm TSMC technology and operates with a voltage supply of ±1.8V. The results of the simulation were collected using PSPICE software (version 17.4). These design solutions demonstrate exceptional efficiency, delivering significant amplification, high frequency, and minimal power usage. In addition, the paper demonstrates the implementation and simulation outcomes of a folded cascode CMOS operational transconductance amplifier utilizing the water cycle algorithm, MATLAB was employed for this purpose. Using WCA in the design of an OTA for folded cascode CMOS OTA results in significant improvements in performance metrics. Experiences a significant increase in voltage gain, with an increase in gain bandwidth by a factor of five compared to the algorithm-free design. In addition, power consumption is reduced by 15.5%, and the common mode rejection ratio is improved by 15.18% compared to the non-WCA folded cascode CMOS OTA design. The results highlight the effectiveness of the WCA technique as a powerful optimization strategy to improve the performance of folded cascode CMOS OTA. [ABSTRACT FROM AUTHOR]

In this paper, we present a 0.3 V body-driven operational transconductance amplifier (OTA) that exploits a biasing approach based on the use of a replica loop with gain. An auxiliary amplifier is exploited both in the current mirror load of the first stage of the OTA and in the replica loop in order to achieve super-diode behavior, resulting in low mirror gain error, which enhances CMRR, and robust biasing. Common-mode feedforward, provided by the replica loop, further enhances CMRR. Simulations in a 180 nm CMOS technology show 65 dB gain with 2 kHz unity-gain frequency on a 200 pF load when consuming 9 nW. Very high linearity with a 0.24% THD at 90% full-scale and robustness to PVT variations are also achieved. [ABSTRACT FROM AUTHOR]

Objectives: To update recent information on contamination levels of mycotoxins in South Korea. Materials and methods: A total of 208 samples sourced from the feeds of swine farms were collected. The contamination levels of mycotoxins, which are aflatoxin (Afla), ochratoxin A (OTA), deoxynivalenol (DON), zearalenone (ZEN), fumonisin (FUM), and T-2 toxin, were investigated by enzyme-linked immunosorbent assays (ELISAs). Results: The detection levels of the total samples were 78.91% for DON, 75.24% for Afla, 47.02% for ZEN, 68.31% for FUM, and 5.94% for OTA and T-2, which were not detected at all. Most of the analyzed mycotoxins showed significant high occurrences in 47.02%–78.91% of the swine feed samples. 11 of the 152 alfa-positive samples exceeded the maximum residue limit (MRL) of Afla proposed by the Korean regulation. In the analysis of mycotoxin detection levels by growth stage, ZEN was found in the nursery stage at a remarkably high concentration level (126.46 ± 63.76 ppb), exceeding the MRL of ZEN for piglets proposed by the European Commission. This mycotoxin was also found in the samples from the gestation barn (89.04 ± 46.05 ppb) and the farrowing house (105.58 ± 94.12) at a high concentration level. Afla was found in the nursery stage at a high concentration (8.00 ± 2.22 ppb), approaching the MRL (10 ppb) of Afla proposed by the Korean regulation. Conclusion: These results indicate that many swine farms in South Korea are still exposed to mycotoxin risk, and special attention and surveillance are necessary for these mycotoxin risks in swine farms. [J Adv Vet Anim Res 2024; 11(1.000): 125-131]

The presence of turning points (stationary points like maxima and minima) in the Parameter-versus-state map (PSM) curve of a memristor can be beneficial in several memristive uses like multi-level logic design, multi-bit memories, and chaos generation circuits. Surprisingly the memristors with these types of PSM curves exhibit multiple crossing points in the transient input v-i contours. In this paper, the memductance model has been derived for such non-linear memristors exhibiting multi-cross-over characteristics. In the presented framework, the coefficients-related condition for the multi-turning point PSM curve has been derived, a necessary condition for the multi-crossing v-i contour. The condition related to the memristor operating parameters has also been reported taking both input signal and initial states into consideration. To realise the derived memductance model corresponding to the three cross-over memristive behaviour, an OTA-based memristor emulator has been developed. Unlike some existing fractional order non-symmetric multi-crossing memristor emulators, the proposed emulator circuit realises an integer order memristor function operating at moderate frequencies. The realised emulator uses only four OTAs and three grounded passive circuit elements with no external multiplier. For the CMOS implementation of employed OTA, the simulation results are obtained to verify the three pinch-off behaviour. [ABSTRACT FROM AUTHOR]

The escalating advancement in Software-Defined Vehicles (SDVs) necessitates a formidable strategy for firmware updates, where traditional methods often fall short of guaranteeing absolute integrity. Although decentralization has been explored in studies for firmware integrity verification using blockchain technology, it lacks comprehensive validation in the context of automotive over-the-air (OTA) updates. By recognizing the limitations of current practices and the partial validation of decentralized approaches, such as blockchain, in the automotive sector, our study introduces a novel mechanism for firmware over-the-air (FOTA) updates. This mechanism is grounded in the widely adopted message queuing telemetry transport (MQTT) protocol, integral to the Internet of Things (IoT) domain, and leverages Merkle tree-based blockchain verification to fortify the fidelity and efficiency of firmware updates. Our proposed solution not only prioritizes the stability crucial to automotive OTA updates but also ensures that performance is not compromised. This dual focus on reliability and efficiency represents a significant stride forward in the development of secure, scalable SDV firmware update protocols. [ABSTRACT FROM AUTHOR]

Mycotoxins have been linked to adverse health impacts, including liver cancer and kidney diseases. The objectives of the current study were to evaluate the dietary exposure of Lebanese adults to multi-mycotoxins (aflatoxin B1 (AFB1), aflatoxin M1 (AFM1), ochratoxin A (OTA), ochratoxin B (OTB), deoxynivalenol (DON), T-2 and HT-2) and to assess their associated health risks. Hence, a nationally representative sample of 449 participants aged 18-64 years old were interviewed to obtain their socio-demographic characteristics, food consumption data and exposure estimates. A food frequency questionnaire and 24 h-recall were used to collect data. The concentration of mycotoxins in all foods consumed by the participants was collected from previous national published studies. The estimated daily intake (EDI), the hazard quotient (HQ) and the margin of exposure (MOE) were calculated. The total exposure to AFB1, AFM1, OTA and DON was 1.26, 0.39, 4.10 and 411.18 ng/kg bw/day, respectively. The MOE to AFB1, AFM1, OTA and DON in the Lebanese food basket was 316, 1454, 3539 and 510, respectively, indicating high health-related risks. Per food items, the MOE to AFB1 was below 10,000 in cereals (466.5), mainly in rice (827.9) and Burgul (4868.5). Similarly, the MOE to OTA in cereals was 1439, in which bread (4022), rice (7589) and bulgur (7628) were considered unsafe. Moreover, the MOE to DON in cereals (605) is alarming, especially in bread (632) and manakesh (6879). The MOE to AFM1 in dairy products was 1454, indicating health-related risks with a focus on yogurt (9788) and labneh (8153). As for the herbs/spices group and traditional dishes, the MOE to AFB1 was relatively lower than 10,000 (3690 and 1625, respectively), with a focus on thyme (2624) and kishik (3297), respectively. It is noteworthy that the MOE to DON and the MOE to OTA in traditional foods and coffee were lower than 10,000 (8047 and 8867, respectively). All hazard quotient (HQ) values were below 1, except the HQ value of milk and dairy products (1.96). The intake of some food groups varied between age categories, corresponding to differences in EDI between them. Thus, it is essential to put control measures in place to decrease the contamination and exposure to mycotoxins by Lebanese consumers. [ABSTRACT FROM AUTHOR]

Abstract A four‐stage CMOS operational amplifier is proposed in this work. The designed amplifier is frequency compensated via two differential blocks and two Miller capacitors. Unlike well‐known frequency compensation methods, the proposed compensation leaves the output node while exploiting extremely smaller capacitors compared to conventional approaches. The presented approach is modeled symbolically and realized at the circuit level via the Hspice circuit simulator and 0.18 μm CMOS technology. Good agreements between two separate simulation paths verify the validity and accuracy of the proposed approach. Ample simulation results are reported to investigate the proposed amplifier regarding parameter mismatches. According to the simulation results, the proposed four‐stage amplifier is an excellent candidate to be used in larger systems such as data converters, modulators, and sensors while it shows more than 169 dB as DC‐gain, 10 MHz as unity gain frequency with power consumption less than 500 μW.

In the last years several ultra-low voltage (ULV) operational transconductance amplifiers (OTAs) with supply voltages below 0.5V have been proposed in the literature. To achieve high gain, multi-stage amplifiers are frequently exploited, in spite of the complexity of design and compensation approaches, whereas cascode and regulated-cascode OTA topologies have rarely been exploited to implement ULV amplifiers. On the other hand, most ULV amplifiers are designed for IoT and biomedical applications in which reducing power consumption is the most important specification, and MOS devices are operated in the subthreshold region. This paper focuses on exploiting the subthreshold operating region to design ULV single-stage OTAs that utilize an output cascoded branch to increase the equivalent output resistance and, consequently, the overall voltage gain. A detailed analytical study of the conditions for triode and saturation regions for MOS devices operating in deep subthreshold region is presented to demonstrate that, for an appropriate choice of the inversion coefficient (IC), a cascode configuration exhibits higher gain than a single transistor, for the same voltage overhead, even in ULV conditions. More specifically, the results presented in this work demonstrate that 4 MOS devices (2 NMOS and 2 PMOS) can be reliably stacked to build a complementary cascode amplifier, even with a supply voltage as low as 0.4V. We also present a novel topology of regulated-cascode amplifier suitable to be operated with a supply voltage of 0.4V and a voltage gain approaching 100dB. Simulation results referring to a 180nm CMOS technology and including PVT and mismatch variations confirm state-of-the-art performances, as well as the good robustness of the proposed regulated-cascode ULV OTA.

In this paper we introduce an improved standard-cell-based voltage amplifier cell with low output resistance. The proposed amplifier cell exhibits a voltage gain whose value can be accurately set by the number of paralleled inverters, and its output static voltage is well controlled through a replica bias approach. A three-stage fully synthesizable OTA architecture exploiting the improved voltage amplifier is also proposed. The OTA has been designed referring to the standard-cell library of a 180nm CMOS technology with a supply voltage of 0.3V and a nominal power consumption of only 6.63 nW, and exhibits a dc-gain of 73.5 dB with a gain-bandwidth-product of 9.63 kHz. A comparison against the state of the art of ultra-low-voltage OTAs has shown that the proposed amplifier exhibits the best value of the small signal figures of merit.

One of the main challenges boutique hotels and resorts face is the direct outreach to tourists and customers. As a result, these independent hotels often resort to online platforms such as Agoda and Airbnb to expand their customer base. However, this approach comes at the cost of losing revenue to Online Travel Agencies (OTAs) that solely focus on room sales, hindering the establishment of a strong brand image for boutique hotels and resorts. Considering the heavy reliance on OTAs, this paper focuses on the development of GoHoliday, a cross-platform mobile app prototype that aims to bridge the gap between boutique hotels and users. This mobile application seamlessly integrates a booking engine, an AI assistant for trip planning, and an experience-sharing platform, enhancing the app's capabilities alongside other features. By implementing the GoHoliday mobile application, boutique hotels can maximize their reach and establish a distinct brand identity by directly serving their valuable guests with more personalized arrangements. [ABSTRACT FROM AUTHOR]

Simple Summary: Mycotoxins, produced by certain types of mold, can present a significant challenge for farm animals, particularly chickens. Among these mycotoxins, Ochratoxin A, created by common molds, is considered one of the most harmful. The absorption of these mycotoxins by animals can be mitigated by incorporating specific substances into their feed that absorb the toxins. Opoka, a rock composed of tiny organic particles, emerges as a potential candidate for this purpose due to its unique structure, which contains numerous small spaces capable of trapping toxins. In a recent study, 2% of Opoka was added to chicken feed. The growth and immune response of the birds were measured, revealing that the weight loss induced by the mycotoxin could be counteracted by including Opoka in the feed. Chickens consuming the Opoka-enhanced feed exhibited increased white blood cells and higher blood glucose levels. These findings suggest that Opoka has the potential to play a protective role against mycotoxin-induced damage. Consequently, introducing Opoka to chicken feed appears to be a promising strategy for shielding chickens from the harmful effects of these molds. Mycotoxins, such as Ochratoxin A (OTA), originating from fungi like Aspergillus and Penicillium, represent serious health hazards to poultry. The use of mycotoxin-adsorbing feed additives can reduce these risks. Opoka, a porous transitional rock, shows promise as one of these additives. This study is the first to examine the effect of Opoka administered with OTA on zootechnical parameters and the immune response of chickens. A 42-day investigation examined the impact of 1% of Opoka supplementation in feed on OTA-challenged broiler chickens. Seventy-two chickens were allocated into three groups of twenty-four individuals each: a control group, an OTA-exposed (2 mg/kg feed) group, and an OTA (2 mg/kg feed) plus 1% of Opoka group. Growth and blood parameters were monitored at predetermined intervals, and comprehensive biochemical, hematological, and cytometric analyses were conducted. The study showed that OTA exposure had a negative impact on chicken weight gain. However, adding Opoka to the diet improved weight gain, indicating its potential as a protective agent. Chickens fed with Opoka also had an increased white blood cell count, which suggests an improved immune response and elevated glucose and cholesterol concentrations. These findings indicate that Opoka may be useful in mitigating health complications caused by OTA exposure in broilers. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to identify the main factors for the quality of hotel services and to verify the SERVQUAL measurement scale commonly used in the services sector. In order to achieve this goal, an innovative approach of quantitative and qualitative content analysis of reviews published by users of the reservation portals Hotels.com and Booking.com was used. The study was based on more than 167,000 opinions on 3,4,5-star hotels located in Warsaw. They were ‘scraped’ with an indexing robot. The research outlines a list of the most important topics raised in those comments which correspond to the factors of perceived service quality of hotels. Among these are location, room attributes, cleanliness, breakfast and staff. In addition, the most important criteria used by customers to describe each of the listed elements are also reported. The results made it possible to identify differences between the operationalization of the constructs indicated in the SERVQUAL scale and the descriptions of each factor in the spontaneous comments of internet users. Thus, the need for adjustment to the current operationalizations of the SERVQUAL model to better reflect the sentiments of consumers in the hotel industry, or even developing a completely new tool for measuring service quality, was demonstrated.

In this paper, a rail-to-rail transconductance stable and enhanced ultra-low-voltage operational transconductance amplifier (OTA) is proposed for electrocardiogram (ECG) signal processing. The variation regularity of the bulk transconductance of pMOS and nMOS transistors and the cancellation mechanism of two types of transconductance variations are revealed. On this basis, a transconductance stabilization and enhancement technique is proposed. By using the “current-reused and transconductance-boosted complementary bulk-driven pseudo-differential pairs” structure, the bulk-driven pseudo-differential pair during the input common-mode range (ICMR) is stabilized and enhanced. The proposed OTA based on this technology is simulated using the TSMC 0.18 μm process in a Cadence environment. The proposed OTA consumes a power below 30 nW at a 0.4 V voltage supply with a DC gain of 54.9 dB and a gain-bandwidth product (GBW) of 14.4 kHz under a 15 pF capacitance load. The OTA has a high small signal figure-of-merit (FoM) of 7410 and excellent common-mode voltage (VCM) stability, with a transconductance variation of about 1.35%. Based on a current-scaling version of the proposed OTA, an OTA-C low-pass filter (LPF) for ECG signal processing with VCM stability is built and simulated. With a −3 dB bandwidth of 250 Hz and a power consumption of 20.23 nW, the filter achieves a FoM of 3.41 × 10−13, demonstrating good performance.

An approach to design analog building blocks based on digital standard cells is presented in this work. By ensuring that every CMOS inverter from a standard-cell library operates with a well-defined quiescent current and output voltage, the suggested method makes it possible to construct analog circuits that are resistant against PVT variations. The method uses the local supply voltages connected to the source terminals of the p-channel and n-channel MOS transistors of the standard-cell inverters as control inputs. It is based on adaptive supply voltage generator (ASVG) reusable blocks, which are comparable to those used in digital applications to handle process variations. All of the standard-cell inverters used for analog functions receive the local supply voltages produced by the ASVGs, which enable setting each cell’s quiescent current to a multiple of a reference current and each cell’s static output voltage to an appropriate reference voltage. Both the complete custom design of the ASVG blocks and a theoretical study of the feedback loop of the ASVG are presented. An application example through the design of a fully synthesizable two-stage operational transconductance amplifier (OTA) is also provided. The TSMC 180 nm CMOS technology has been used to implement both the OTA and the ASV generators. Simulation results have demonstrated that the proposed approach allows to accurately set the quiescent current of standard-cell inverters, dramatically reducing the effect of PVT variations on the pmain performance parameters of the standard-cell-based two-stage OTA.

In 2004, the EFSA Panel on Contaminants in the Food Chain (CONTAM) adopted a Scientific Opinion on the risks to animal health and transfer from feed to food of animal origin related to the presence of ochratoxin A (OTA) in feed. The European Commission requested EFSA to assess newly available scientific information and to update the 2004 Scientific Opinion. OTA is produced by several fungi of the genera Aspergillus and Penicillium. In most animal species it is rapidly and extensively absorbed in the gastro‐intestinal tract, binds strongly to plasma albumins and is mainly detoxified to ochratoxin alpha (OTalpha) by ruminal microbiota. In pigs, OTA has been found mainly in liver and kidney. Transfer of OTA from feed to milk in ruminants and donkeys as well as to eggs from poultry is confirmed but low. Overall, OTA impairs function and structure of kidneys and liver, causes immunosuppression and affects the zootechnical performance (e.g. body weight gain, feed/gain ratio, etc.), with monogastric species being more susceptible than ruminants because of limited detoxification to OTalpha. The CONTAM Panel considered as reference point (RP) for adverse animal health effects: for pigs and rabbits 0.01 mg OTA/kg feed, for chickens for fattening and hens 0.03 mg OTA/kg feed. A total of 9,184 analytical results on OTA in feed, expressed in dry matter, were available. Dietary exposure was assessed using different scenarios based on either model diets or compound feed (complete feed or complementary feed plus forage). Risk characterisation was made for the animals for which an RP could be identified. The CONTAM Panel considers that the risk related to OTA in feed for adverse health effects for pigs, chickens for fattening, hens and rabbits is low. [ABSTRACT FROM AUTHOR]

A novel ternary Y-DNA walker amplification strategy designed fluorescence aptasensor based on Au@SiO2@Fe3O4 nanomaterials for ultrasensitive and specific ochratoxin A detection in food samples is presented. Au@SiO2@Fe3O4 nanomaterials provide the loading platform as well as separation and recovery properties for the ternary Y-DNA walker. The ternary Y-DNA walker is designed to be driven by Nb.BbvCI cleaving a large number of FAM probes to achieve signal amplification. Since Ochratoxin A (OTA) can bind to the constituent aptamer in the ternary Y-DNA walker, adding OTA will destroy the structure of the ternary Y-DNA walker, thereby inhibiting the driving process of the walker. After optimization of various parameters, a standard curve was obtained from 100 to 0.05 ng·mL−1 of OTA with the limit of determination of 0.027 ng·mL−1. The spiked recovery of peanut samples by this method was 82.00–93.30%, and the aptasensor showed excellent specificity and long-term stability. This simple, robust, and scalable oligonucleotide chain-based ternary Y-DNA walker can provide a general signal amplification strategy for trace analysis. [ABSTRACT FROM AUTHOR]

An ochratoxin A (OTA) electrochemical biosensor based on a cascade signal amplification strategy with Ag nanoparticles (AgNPs) and ring opening polymerization (ROP) was constructed. The large specific surface area of AgNPs was used to increase the loading of OTA aptamer on the electrode surface, enhancing the ability to capture OTA as a way to achieve the first signal amplification. The OTA antibody modified with polyethylenimine specifically recognizes the OTA, forming an aptamer-OTA-antibody sandwich structure. The amino group on polyethylenimine initiates the ROP reaction with α-amino acid-n-carboxylic anhydride-ferrocene (NCA-Fc) as the monomer. A large number of electrochemical signal units of ferrocene are introduced into the sensing system for a second signal amplification. By amplifying the signal twice, the sensitivity of the sensor is improved. Under the optimal conditions, the detection range of the sensor is 1 pg·mL−1 ~ 1 μg·mL−1, while the detection limit is as low as 117 fg·mL−1. Moreover, the sensor has the advantages of high sensitivity, good stability and selectivity. Standard addition recovery experiment proved that the sensing system can be successfully used for the detection of OTA in four actual samples with recoveries in the range 90.0 to 113% with RSDs of 0.6 to 5.2%, providing a new idea for the pollution assessment of mycotoxins. [ABSTRACT FROM AUTHOR]

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Copyright of Tourism Tribune / Lvyou Xuekan is the property of Tourism Institute of Beijing Union University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study carried out a scenario experiment in Guangxi, China, and used a questionnaire to obtain the research data of the subjects to explore the service recovery effect of local online travel agencies (OTAs) from the perspective of consumer psychology. The empirical results show that consumer confusion will significantly worsen negative word-of-mouth, and negative word-of-mouth will reduce their repurchase intention. In the above empirical impact relationship research, it shows that negative word-of-mouth and consumer forgiveness play a mediating effect and a moderating effect respectively. Because this study is conducive to responding to and solving the new scenario and problems in the practice of OTA services. It will help to improve the risk resistance of OTA enterprises by providing effective service recovery strategies for these enterprises. [ABSTRACT FROM AUTHOR]

A stainless steel mesh (SSM) with the feature of flexibility was employed as the colorimetric biosensor substrate, and aptamer was bond onto the surface of the SSM. Through the cross-linking of ionic liquids (ILs), AuPt nanoparticles were deposited onto the surface of Fe3O4 material to obtain a magnetic nanozyme with high peroxidase catalytic activity and rapid color change. Through the competing interaction of OTA and cDNA with aptamer, AuPt@IL@Fe3O4 signal probe was separated to catalyze the 3,3′,5,5′-tetramethylbenzidine/hydrogen peroxide (TMB/H2O2) system to observe the color by bare eye and record the absorbance at 652 nm using a UV-spectrophotometer. Through the study of the catalytic properties on the basis of the Michaelis equation, AuPt@IL@Fe3O4 nanozyme presented a Vmax of 3.85 × 10−8 M s−1 and Km of 0.01 mM. Under the optimized conditions, the linear range of the colorimetric biosensor towards OTA was 5–100 ng mL−1, and the detection limit was 0.078 ng mL–1. This biosensor was applied to beer and corn samples with recoveries of 70.4–102.6% and 93.3–104.7%, respectively. Results showed that this sensor is a portable, rapid, economical, sensitive visual sensing platform towards mycotoxin in real samples. [ABSTRACT FROM AUTHOR]

In this paper, we present a 0.3 V body-driven operational transconductance amplifier (OTA) that exploits a biasing approach based on the use of a replica loop with gain. An auxiliary amplifier is exploited both in the current mirror load of the first stage of the OTA and in the replica loop in order to achieve super-diode behavior, resulting in low mirror gain error, which enhances CMRR, and robust biasing. Common-mode feedforward, provided by the replica loop, further enhances CMRR. Simulations in a 180 nm CMOS technology show 65 dB gain with 2 kHz unity-gain frequency on a 200 pF load when consuming 9 nW. Very high linearity with a 0.24% THD at 90% full-scale and robustness to PVT variations are also achieved.

Mycotoxins have been linked to adverse health impacts, including liver cancer and kidney diseases. The objectives of the current study were to evaluate the dietary exposure of Lebanese adults to multi-mycotoxins (aflatoxin B1 (AFB1), aflatoxin M1 (AFM1), ochratoxin A (OTA), ochratoxin B (OTB), deoxynivalenol (DON), T-2 and HT-2) and to assess their associated health risks. Hence, a nationally representative sample of 449 participants aged 18-64 years old were interviewed to obtain their socio-demographic characteristics, food consumption data and exposure estimates. A food frequency questionnaire and 24 h-recall were used to collect data. The concentration of mycotoxins in all foods consumed by the participants was collected from previous national published studies. The estimated daily intake (EDI), the hazard quotient (HQ) and the margin of exposure (MOE) were calculated. The total exposure to AFB1, AFM1, OTA and DON was 1.26, 0.39, 4.10 and 411.18 ng/kg bw/day, respectively. The MOE to AFB1, AFM1, OTA and DON in the Lebanese food basket was 316, 1454, 3539 and 510, respectively, indicating high health-related risks. Per food items, the MOE to AFB1 was below 10,000 in cereals (466.5), mainly in rice (827.9) and Burgul (4868.5). Similarly, the MOE to OTA in cereals was 1439, in which bread (4022), rice (7589) and bulgur (7628) were considered unsafe. Moreover, the MOE to DON in cereals (605) is alarming, especially in bread (632) and manakesh (6879). The MOE to AFM1 in dairy products was 1454, indicating health-related risks with a focus on yogurt (9788) and labneh (8153). As for the herbs/spices group and traditional dishes, the MOE to AFB1 was relatively lower than 10,000 (3690 and 1625, respectively), with a focus on thyme (2624) and kishik (3297), respectively. It is noteworthy that the MOE to DON and the MOE to OTA in traditional foods and coffee were lower than 10,000 (8047 and 8867, respectively). All hazard quotient (HQ) values were below 1, except the HQ value of milk and dairy products (1.96). The intake of some food groups varied between age categories, corresponding to differences in EDI between them. Thus, it is essential to put control measures in place to decrease the contamination and exposure to mycotoxins by Lebanese consumers.

Abstract In 2004, the EFSA Panel on Contaminants in the Food Chain (CONTAM) adopted a Scientific Opinion on the risks to animal health and transfer from feed to food of animal origin related to the presence of ochratoxin A (OTA) in feed. The European Commission requested EFSA to assess newly available scientific information and to update the 2004 Scientific Opinion. OTA is produced by several fungi of the genera Aspergillus and Penicillium. In most animal species it is rapidly and extensively absorbed in the gastro‐intestinal tract, binds strongly to plasma albumins and is mainly detoxified to ochratoxin alpha (OTalpha) by ruminal microbiota. In pigs, OTA has been found mainly in liver and kidney. Transfer of OTA from feed to milk in ruminants and donkeys as well as to eggs from poultry is confirmed but low. Overall, OTA impairs function and structure of kidneys and liver, causes immunosuppression and affects the zootechnical performance (e.g. body weight gain, feed/gain ratio, etc.), with monogastric species being more susceptible than ruminants because of limited detoxification to OTalpha. The CONTAM Panel considered as reference point (RP) for adverse animal health effects: for pigs and rabbits 0.01 mg OTA/kg feed, for chickens for fattening and hens 0.03 mg OTA/kg feed. A total of 9,184 analytical results on OTA in feed, expressed in dry matter, were available. Dietary exposure was assessed using different scenarios based on either model diets or compound feed (complete feed or complementary feed plus forage). Risk characterisation was made for the animals for which an RP could be identified. The CONTAM Panel considers that the risk related to OTA in feed for adverse health effects for pigs, chickens for fattening, hens and rabbits is low.

In this paper, a new memristor-less fractional-order meminductor emulator has been presented based on two operational transconductance amplifiers (OTAs), and a current differencing buffered amplifier (CDBA). The integer and fractional capacitors have been utilized in the proposed design of floating and grounded types. It also offers the freedom of conversion between incremental and decremental in both the types i.e., grounded, and floating. The pinched hysteresis loops have been obtained up to 3 MHz for both incremental and decremental setups of the proposed fractional-order meminductor emulator. The simulation results were achieved using the LTSpice tool with 180 nm CMOS technology specifications. The suggested meminductor emulator's performance has also been compared to that of existing emulators reported in the literature. To test the effectiveness of the suggested fractional-order meminductor emulator, an adaptive learning circuit has been simulated. [ABSTRACT FROM AUTHOR]

Meminductors are memory-based elements, which are gaining a lot of popularity as a result of their applications in widespread areas. However, due to the non-availability of their off-the-shelf ICs, designers are trying to find alternatives of meminductor emulators. This paper presents a generalized approach to designing a meminductor emulator from an active inductor circuit. An active inductor circuit having a current conveyor (CC), operational transconductance amplifier (OTA), and a grounded capacitor has been utilized. The idea is encouraged by the thought of putting memory in conventional active inductor circuits. In the proposed configuration, one additional block namely a current differencing buffered amplifier (CDBA) and an extra grounded capacitor have been used to modify the active inductor circuit into a meminductor emulator circuit. The goal is to implement a meminductor emulator employing active blocks which can be designed using commercially available ICs. Simulation results of the proposed emulator are obtained using the LTspice tool along with 0.18 µm CMOS technology parameters. The essential testimonials, pinched hysteresis loops, and non-volatility tests, confirm that the suggested circuit works as a meminductor emulator. Furthermore, the pinched hysteresis loops are observed for a large range of frequencies, verifying the wide dynamic frequency range of the suggested circuit. To assess how well the suggested meminductor emulator performs, a chaotic oscillator has been developed. [ABSTRACT FROM AUTHOR]

A novel three-dimensional (3D) porous nitrogen-sulfur co-doped carbon (N–S–C) mesh was synthesized and used for the first time as the quenching material to construct a fluorescent aptasensor for ochratoxin A (OTA) detection. The fluorescent aptasensor with enzyme-free signal amplification strategy was developed by using cDNA as a promoter to trigger hybridization chain reaction (HCR), which effectively improved the sensitivity of this aptasensor. In the absence of OTA, 3D porous N–S–C mesh can adsorb carboxyfluorescein FAM-labeled hairpin DNA1 (H1-FAM) and hairpin DNA2 (H2) and quench the fluorescence of FAM. In the presence of the OTA, the OTA specifically binds to the aptamer strand and the DNA duplex undergoes dissociation. The released cDNA in turn serves as a promoter for HCR, and the strand assembly of H1-FAM and H2 is triggered by the promoter to generate long-strand DNA polymers via HCR, resulting in an increasing fluorescent signal. Under optimal conditions, there was a good linear relationship between lgCOTA and fluorescence intensity difference in the range 0.01–500 ng/mL (R2 = 0.993), and the detection limit was 2.7 pg/mL. The designed sensor platform was applied to determine spiked OTA in peanut, wheat flour, corn flour, black tea, and wine with recoveries in the range of 94.4–119.6%. [ABSTRACT FROM AUTHOR]

This paper suggests a new operational transconductance amplifier (OTA) based electronically tunable transimpedance-mode first-order universal filter (FOUF). The suggested FOUF produces all-pass (AP), high-pass (HP) and low-pass (LP) filter responses simultaneously. It employs three OTAs, two grounded resistors and only one grounded capacitor. Owing to use of grounded passive elements, the suggested FOUF is suitable for integrated circuit implementation. It operates at low power supply voltages. Additionally, the resonance frequency of the suggested AP filter can be adjusted in a wide frequency range. However, the suggested FOUF consists of only one matching condition. Moreover, a sinusoidal quadrature oscillator (QO) application that is derived from the suggested FOUF topology is given. The suggested FOUF and its QO application are simulated by using 0.18- μ m TSMC technology parameters in the SPICE program to validate the presented theory. Finally, an experimental test is performed to demonstrate workability of the suggested AP filter. [ABSTRACT FROM AUTHOR]

This paper describes the design and implementation of a 39 GHz 256-element hybrid active phased array antenna system with 16 individual digital transceivers, and its wireless multi-user, multi-input, multi-output verification. An earlier version of this paper was presented at the 2021 51st European Microwave Conference and was published in its Proceedings [1]. Using the prototype device, a single carrier transmission test assuming a mobile backhaul link and a MU-MIMO transmission test using a zero-forced orthogonal multi-beam based on channel reciprocity assuming an access link was performed. As a result, an EIRP of 43 dBm and a data rate of 5.5 Gbps in 1 GHz bandwidth single carrier 128QAM operation and an estimated total throughput of 2.4 Gbps by 3GPP TS38.214 [2] in 100 MHz bandwidth OFDM 8 MU-MIMO operation were achieved, respectively. As far as the author knows, this is the first demonstration for integrated access and backhaul (IAB) application that uses the 39 GHz band. [ABSTRACT FROM AUTHOR]

The rapid rate of population growth and urbanization has impacted the management of municipal solid wastes (MSW) and is increasingly becoming a major concern in many cities in developing countries. Insufficient area coverage for wastes collection, processing system, and unsuitable disposal all appear to be the causal factors. This paper discussed the current situation of solid waste management in Ota municipality as well as the challenges and associated problems. Structured questionnaires, interviews and on-site observations were used for data generation, and subsequently analyzed using descriptive statistics. Results indicated that 28.6% of the respondents incinerate their wastes, while 27.6% of the respondents dispose theirs to public waste bins. About 11.4% deposit their wastes by the road side, while 6.4% dump their wastes in drainages and water bodies. Most respondents incinerate their wastes which would impact negatively on the ozone layer. Results also indicated that 54.3% of the respondents have their wastes disposed regularly, while 66% do not sort their wastes which make them difficult to manage. The city's single dump site was visited in order to have a better understanding of the existing solid waste management measures in place. Other illegal waste dumps in the town were also visited. In order to address the difficulties of solid waste management in the municipality, it is recommended that the state government engage additional Private Service Provider (PSP) operatives to assist with waste collection and transportation, provide suitable facilities, machinery, and equipment, and launch a public awareness campaign. [ABSTRACT FROM AUTHOR]

Studies on new passive elements with memory properties such as memristor, meminductor, and memcapacitor have increased recently. In this article, an operational transconductance amplifier (OTA) based meminductor simulator circuit without using a memristor, which is suitable for the physically produced memristor structure, has charge control, floating structure, and characteristics can be controlled electronically, is proposed. The OTA IC used is based on $0.18\mu \text{m}$ CMOS technology. The meminductor emulator circuit works in high-frequency regions and has low power consumption. Furthermore, the meminductor emulator circuit can be operated both as a decreasing model and an increasing model. Temperature, Monte-Carlo and worst-case analyzes are performed to verify the robustness of the proposed circuit. In this study, a chaotic circuit is designed by taking advantage of the nonlinearity of the proposed meminductor circuit. In addition, a neuromorphic circuit application has been carried out to demonstrate the memory ability of the proposed meminductor circuit. The electronic tunability of the proposed meminductor circuit in both chaotic and neuromorphic applications are demonstrated. The electronic simulations of the applications realized with the proposed meminductor emulator circuit, which are obtained by using the LTspice program.