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BACKGROUND AND OBJECTIVES: Receiving nutrients from fruits and vegetables are essential for public health. However, a large amount of waste is produced during producing, supplying, and consuming these fruits and vegetables. Water, fertilizers and pesticides used for the production of agricultural products can affect the soil and their cultivation environment and finally lead to environmental pollution. Therefore, this study aimed to investigate the amount of fruit and vegetable waste caused by corruption and evaluate its economic loss and health damage.METHODS: The data were collected using the observation technique aided by observation tools and weighing tests to physically analyze and determine the quantity and quality of waste from Tehran’s fruit and vegetable distribution centers. In each center, the waste obtained from fruits and vegetables was stored in special waste tanks at the end of the day, and the waste was transported to outside the center by special waste disposal vehicles. The economic loss of unusable fruits and vegetables was calculated according to the weight of their waste in the fields of agricultural product supply. The data were analyzed using statistical software SPSS, ANOVA statistical test, and Excel software.FINDINGS: The results revealed that the amounts of fruit and vegetable wastes were 12 percent and 24 percent, respectively, accounting for a total loss of 54,891,539 USD. The highest quantity of fruit waste (15 percent) was observed in summer, and the economic loss due to fruit waste was higher in this season. Also, the amounts of vegetable waste in summer and spring were equal to 28 percent and 24 percent, respectively, indicating the higher economic loss due to vegetable in these seasons.CONCLUSION: The results showed that the economic loss due to vegetable waste was greater than the economic loss due to fruit waste. The amount of vegetable waste was 24 percent, representing a high economic loss. The generation and disposal of these wastes caused a great economic loss and health problems due to their unpleasant odor, release of leachate into the environment, and landfill pollution. Therefore, it was recommended to follow appropriate production principles and supply operations. Moreover, a comprehensive waste disposal management, as a practical measure, should be used to prevent and control these problems. The use of modern technology in harvesting, transporting and supplying fruits and vegetables could reduce their lesion, and subsequently reduce the economic loss.

Background: Cryptosporidium spp. is one of the most important parasitic pathogen which causes acute gastroenteritis in human. This study aimed to determine and compare the contamination rates of Cryptosporidium oocysts in some common vegetables that are cultured and consumed in Koya City, Iraq. Methods: Totally, 400 vegetable samples were collected randomly from vegetable farms in Koya city during spring and summer, 2016. The vegetables, including celery, parsley, leek, radish, and green onion were examined for the presence of Cryptosporidium spp. by Ziehl-Neelsen acid-fast staining method. Data were analyzed by SPSS statistical software (version 21). Results: The prevalence rate of Cryptosporidium spp. oocysts in parsley, celery, leek, radish, and green onion were 6.25, 7.50, 6.25, 6.25, and 6.25%, respectively, showing no significant differences (p>0.05). Also, Cryptosporidium spp. oocysts were detected in 12 out of 200 (6%) samples from spring and 14 out of 200 (7%) samples from summer, without any significant difference (p>0.05). Conclusion: Our findings highlighted that if the proper washing as well as disinfecting actions are neglected before consumption of the vegetables, consumption of raw vegetables could be potentially hazardous, inducing Cryptosporidium infection in Iraqi people. DOI: 10.29252/jfqhc.5.3.89

Light propagation facilitates digital information encryption by utilizing Epsilon Negative (ENG) metamaterials as a medium. Achieving the desired encryption hinges on synchronizing two pivotal features: the phase difference and the epsilon shifting of the metamaterials. The proposed metamaterial is intricately designed to represent digital bit 1 (states 0 and 1), contingent upon the arrangement of material multilayers within the metamaterial device. Specifically, state 1 is fashioned through a combination of Graphene and Gold, while state 0 is solely represented by Graphene on a metamaterial structure. The developed structure exhibits right hand metamaterial (epsilon of [Formula: see text]7.20) for state 0 and plasma metamaterial (epsilon [Formula: see text]6.94) for state 1 at 8.6 THz. Notably, the phase difference between 0 and 1 states is around [Formula: see text]. Primarily leveraging the synchronized combination phase and epsilon as the key design parameters for the metamaterial array, the beamforming pattern enables beam steering within the angular range of [Formula: see text] to [Formula: see text]. Secondly, employing a sophisticated material addition strategy involving Gallium Arsenide (GaAs) systematically manipulates the sidelobe in specific directions, thereby providing a mechanism to modulate the sidelobe and concurrently augment spatial resolution. After preparing the metamaterial coded (MC) lens, the source, lens and receiver strategically encrypt the scanning image, employing techniques including Doppler compression and 2D discrete Fourier transform. The proposed MC lens offers applicability like image encryption, security scanning, conveyor systems, hyperlenses and modern cryptography., (© 2024. The Author(s).)

A low-profile dual-band pixelated defected ground antenna has been proposed at 3.5 GHz and 5.8 GHz bands. This work presents a flexible design guide for achieving single-band and dual-band antenna using pixelated defected ground (PDG). The unique pixelated defected ground has been designed using the binary particle swarm optimization (BPSO) algorithm. Computer Simulation Technology Microwave Studio incorporated with Matlab has been utilized in the antenna design process. The PDG configuration provides freedom of exploration to achieve the desired antenna performance. Compact antenna design can be achieved by making the best use of designated design space on the defected ground (DG) plane. Further, a V-shaped transfer function based on BPSO with fast convergence allows us to efficiently implement the PDG technique. In the design procedure, pixelization is applied to a small rectangular region of the ground plane. The square pixels on the designated defected ground area of the antenna have been formed using a binary bit string, consisting of 512 bits taken during each iteration of the algorithm. The PDG method is concerned with the shape of the DG and does not rely on the geometrical dimension analysis used in traditional defected ground antennas. Initially, three single band antennas have been designed at 3.5 GHz, 5.2 GHz and 5.8 GHz using PDG technique. Finally, same PDG area has been used to design a dual-band antenna at 3.5 GHz and 5.8 GHz. The proposed antenna exhibits almost omnidirectional radiation performance with nearly 90% efficiency. It also shows dual radiation pattern property with similar patterns having different polarizations at each operational band. The antenna is fabricated on a ROGERS RO4003 substrate with 1.52 mm thickness. Reflection coefficient and radiation patterns are measured to validate its performance. The simulated and measured results of the antenna are closely correlated. The proposed antenna is suitable for different applications in Internet of Things., (© 2022. The Author(s).)

Continuous and accurate sensing of water content in soil is an essential and useful measure in the agriculture industry. Traditional sensors developed to perform this task suffer from limited lifetime and also need to be calibrated regularly. Further, maintenance, support, and deployment of these sensors in remote environments provide additional challenges to the use of conventional soil moisture sensors. In this paper, a metamaterial perfect absorber (MPA) based soil moisture sensor is introduced. The ability of MPAs to absorb electromagnetic signals with near 100% efficiency facilitates the design of highly accurate and low-profile radio frequency passive sensors. MPA based sensor can be fabricated from highly durable materials and can therefore be made more resilient than traditional sensors. High resolution sensing is achieved through the creation of physical channels in the substrate integrated waveguide (SIW) cavity. The proposed sensor does not require connection for both electromagnetic signals or for adding a testing sample. Importantly, an external power supply is not needed, making the MPA based sensor the perfect solution for remote and passive sensing in modern agriculture. The proposed MPA based sensor has three absorption bands due to the various resonance modes of the SIW cavity. By changing the soil moisture level, the absorption peak shifts by 10 MHz, 23.3 MHz, and 60 MHz, which is correlated with the water content percentage at the first, second and third absorption bands, respectively. Finally, a [Formula: see text] cell array with a total size of [Formula: see text] has been fabricated and tested. A strong correlation between measurement and simulation results validates the design procedure.

Being incident and polarization angle insensitive are crucial characteristics of metamaterial perfect absorbers due to the variety of incident signals. In the case of incident angles insensitivity, facing transverse electric (TE) and transverse magnetic (TM) waves affect the absorption ratio significantly. In this scientific report, a crescent shape resonator has been introduced that provides over 99% absorption ratio for all polarization angles, as well as 70% and 93% efficiencies for different incident angles up to [Formula: see text] for TE and TM polarized waves, respectively. Moreover, the insensitivity for TE and TM modes can be adjusted due to the semi-symmetric structure. By adjusting the structure parameters, the absorption ratio for TE and TM waves at [Formula: see text] has been increased to 83% and 97%, respectively. This structure has been designed to operate at 5 GHz spectrum to absorb undesired signals generated due to the growing adoption of Wi-Fi networks. Finally, the proposed absorber has been fabricated in a [Formula: see text] array structure on FR-4 substrate. Strong correlation between measurement and simulation results validates the design procedure.

Purpose: Genotoxic wastes are one type of hospital wastes that are extremely dangerous and may cause cell mutation or cancer and their disposal should be taken seriously. Cytotoxic drugs are main component of these wastes. The purpose of this study was to determine the types and quantities of genotoxic wastes in hospitals of Tehran University of Medical Sciences and evaluation of genotoxic waste management index., Methods: For this purpose, a questionnaire was used to collect data. Each question was scored according to compliance or non-compliance with the law, and genotoxic hospital waste management index was calculated for each hospital., Results: Various parameters including waste generation rate, segregation, collection, transportation, storage, disposal and the hygiene of personnel were evaluated. The results showed that 60% of hospitals ranked medium, 27% ranked poor and 13% ranked as very poor according to this index., Conclusions: Since the condition of genotoxic waste management in this study was ranked as medium, therefore some steps of hospital waste management system require improvement., Competing Interests: Compliance with ethical standardsNo potential conflict of interest was reported by the author.

Due to the growing implications of energy costs and carbon footprints, the need to adopt inexpensive, green energy harvesting strategies are of paramount importance for the long-term conservation of the environment and the global economy. To address this, the feasibility of harvesting low power density ambient RF energy simultaneously from multiple sources is examined. A high efficiency multi-resonant rectifier is proposed, which operates at two frequency bands (478-496 and 852-869 MHz) and exhibits favorable impedance matching over a broad input power range (-40 to -10 dBm). Simulation and experimental results of input reflection coefficient and rectified output power are in excellent agreement, demonstrating the usefulness of this innovative low-power rectification technique. Measurement results indicate an effective efficiency of 54.3%, and an output DC voltage of 772.8 mV is achieved for a multi-tone input power of -10 dBm. Furthermore, the measured output DC power from harvesting RF energy from multiple services concurrently exhibits a 3.14 and 7.24 fold increase over single frequency rectification at 490 and 860 MHz respectively. Therefore, the proposed multi-service highly sensitive rectifier is a promising technique for providing a sustainable energy source for low power applications in urban environments.

We report the resection of a leiomyosarcoma of the azygos vein in an elderly woman. The rare nature of the tumor and the unusual site of origin are discussed.