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1.
Food Sci Nutr ; 12(5): 3282-3294, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38726437

RESUMO

This study investigated the possibility of using active coatings based on Zedo gum containing essential oils of Zataria multiflora Boiss (ZE) and tarragon (TE) to increase the shelf life and maintain the quality of freshly cut potato strips. The chemical compositions of ZE and TE were initially identified, and their antioxidant and antimicrobial activities were investigated. ZE consisted mainly of carvacrol (26.26%), p-cymene (21.50%), thymol (18.05%), and linalool (11.31%), and those of TE comprised p-allylanisole (81.92%), ß-Ocimene E (8.06%), and ß-Ocimene Z (5.35%). Afterwards, a Zedo gum active coating (1% v/w) containing 1% (v/v) essential oil was prepared, and the produced coating solutions were used to soak the potato strips for 5 min. The coated potatoes were kept fresh in a refrigerator for 9 days, and their quality characteristics were examined every 3 days. The results show that the weight loss, browning index, total microbial count, and mold and yeast counts in the strips increased during 9 days of cold storage, and hardness decreased (p < .05). However, the coatings of strips, especially those containing essential oils, reduced the intensity of changes in moisture, color, and hardness, increased microbial stability, and maintained the sensory acceptance of strips compared with the uncoated sample (control). Finally, this study demonstrated that the quality and shelf life of fresh potato strips can be improved by using active coatings based on Zedo gum containing ZE and TE (especially ZE).

2.
PLoS One ; 19(5): e0302634, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38718001

RESUMO

In this paper, a new microstrip triplexer is designed to work at 2.5 GHz, 4.4 GHz and 6 GHz for mid-band 5G applications. All channels are flat with three low group delays (GDs) of 0.84 ns, 0.75 ns and 0.49 ns, respectively. Compared to the previously reported works, the proposed triplexer has the minimum group delay. The designed triplexer has 18.2%, 13.7%, 23.6% fractional bandwidths (FBW%) at 2.5 GHz, 4.4 GHz and 6 GHz, respectively. The obtained insertion losses (ILs) are low at all channels. These features are obtained without a noticeable increase in the overall size. A novel and simple resonator is used to design the proposed triplexer, which includes two pairs of coupled lines combined with a shunt stub. A perfect mathematical analysis is performed to find the resonator behavior and the layout optimization. The type of shunt stub is determined mathematically. Also, the smallness or largeness of some important physical dimensions is determined using the proposed mathematical analysis. Finally, the designed triplexer is fabricated and measured, where the measurement results verify the simulations.


Assuntos
Desenho de Equipamento , Tecnologia sem Fio , Tecnologia sem Fio/instrumentação
3.
Toxicon ; 239: 107608, 2024 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-38211806

RESUMO

The health risks caused by aflatoxins, as one of the most important contaminants of human food and feed and the main cause of cancer, especially hepatocellular carcinoma (HCC) were investigated. The aim of the study was to assess the antimutagenic effects of Bifidobacterium lactis (B. lactis) probiotic against aflatoxin B1 (AFB1). The study was conducted with 27 treatments and three replications. The independent variables were aflatoxin concentrations at three levels of 5, 15, and 25 ng/g and probiotic content in three forms of cellular sedimentation (CS), cell-free supernatant (CFS), and cell suspension. The antimutagenic activity of B. lactis against AFB1 was measured. The lowest score of antimutagenic activity of B. lactis was observed in bacterial cellular sediment treatment at 107 CFU/g and 25 ng/g of AFB1 (20.8 ± 3.80%) and the highest score was achieved with cell suspension at 109 CFU/g and 5 ng/g of AFB1 (74.9 ± 7.11%). In addition, the lack of mutagenicity of probiotics was confirmed. Therefore, probiotics not only alleviate aflatoxin in food matrices and benefit the consumer, but also notably decrease mutagenicity of AFB1.


Assuntos
Aflatoxinas , Bifidobacterium animalis , Carcinoma Hepatocelular , Neoplasias Hepáticas , Probióticos , Humanos , Aflatoxina B1/toxicidade , Mutagênicos/toxicidade , Probióticos/farmacologia
4.
PLoS One ; 18(12): e0296272, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38134045

RESUMO

Microstrip couplers play a crucial role in signal processing and transmission in various applications, including RF and wireless communication, radar systems, and satellites. In this work, a novel microstrip 180° coupler is designed, fabricated and measured. The layout configuration of this coupler is completely new and different from the previously reported Rat-race, branch-line and directional couplers. To obtain the proposed coupler, the meandrous coupled lines are used and analyzed mathematically. To improve the performance of our coupler, an optimization method is used. The designed coupler is very compact with an overall size of 0.014λg2. The obtained values of S21 and S31 are -3.45 dB and -3.75 dB, respectively at the operating frequency, while the fractional bandwidth (FBW) is 56.2%. It operates at fo = 1.61 GHz (suitable for 5G applications) and can suppress harmonics up to 2.17fo. Another advantage of this coupler is its low phase imbalance, while the phase difference between S21 and S31 is 180°± 0.023°. Therefore, our device is a balanced coupler with ±0.3 dB magnitude unbalance at its operating frequency. It is important to note that it is very difficult to find a coupler that has all these advantages at the same time. The proposed 180° coupler is fabricated and measured. The comparison shows that the measurement and simulation results are in good agreement. Therefore, the proposed coupler can be easily used in designing high-performance 5G communication systems.


Assuntos
Comunicação , Radar , Animais , Ratos , Simulação por Computador , Processamento de Sinais Assistido por Computador
5.
Sensors (Basel) ; 23(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37050835

RESUMO

Global concerns regarding environmental preservation and energy sustainability have emerged due to the various impacts of constantly increasing energy demands and climate changes. With advancements in smart grid, edge computing, and Metaverse-based technologies, it has become apparent that conventional private power networks are insufficient to meet the demanding requirements of industrial applications. The unique capabilities of 5G, such as numerous connections, high reliability, low latency, and large bandwidth, make it an excellent choice for smart grid services. The 5G network industry will heavily rely on the Internet of Things (IoT) to progress, which will act as a catalyst for the development of the future smart grid. This comprehensive platform will not only include communication infrastructure for smart grid edge computing, but also Metaverse platforms. Therefore, optimizing the IoT is crucial to achieve a sustainable edge computing network. This paper presents the design, fabrication, and evaluation of a super-efficient GSM triplexer for 5G-enabled IoT in sustainable smart grid edge computing and the Metaverse. This component is intended to operate at 0.815/1.58/2.65 GHz for 5G applications. The physical layout of our triplexer is new, and it is presented for the first time in this work. The overall size of our triplexer is only 0.007 λg2, which is the smallest compared to the previous works. The proposed triplexer has very low insertion losses of 0.12 dB, 0.09 dB, and 0.42 dB at the first, second, and third channels, respectively. We achieved the minimum insertion losses compared to previous triplexers. Additionally, the common port return losses (RLs) were better than 26 dB at all channels.

6.
Food Sci Nutr ; 10(10): 3293-3301, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36249982

RESUMO

Nowadays, the development of pH-sensitive smart edible films using biopolymers and natural plant extracts (especially those rich in anthocyanins) has attracted much attention. Therefore, in this study, the intelligent edible film was produced and characterized using cassava starch and pomegranate peel powder (PPP) and the possibility of using production films to monitor the freshness of lamb meat. The smart films were prepared using different concentrations of PPP (2, 4, 6, and 8% w/w) and the solvent casting method. The results showed that the incorporation of PPP had a significant effect on the mechanical parameters of the starch films. With increasing the levels of PPP, the color of the films became darker and redder. Increasing the PPP levels also led to an increase in total phenol content (TPC) (from 0 to 13 mg GAE (gallic acid equivalent)/g) and antioxidant activity (from 0% to 70% DPPH (1,1-diphenyl-2-picryl hydrazyl) radical scavenging) of the produced films (p < .05). The intelligent film was used in the lamb meat packaging, and the color of the film changed from red to green during the storage period at 25°C. The amount of total volatile basic nitrogen (TVB-N) in the meat could be detected by color changes of the intelligent films. Finally, this study demonstrated that the film based on cassava starch and PPP could be used as an intelligent and pH-sensitive film to monitor the freshness of meat and meat products.

7.
Eye Contact Lens ; 48(5): 210-216, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35333790

RESUMO

OBJECTIVE: To evaluate the potential role of different types of contact lenses, such as soft (SCL), hard (HCL), and mini scleral (SCCL), in corneal epithelial thickness with anterior segment optical coherence tomography (AS-OCT). METHODS: In this cross-sectional study, patients who used contact lens at recent 6 months were recruited consecutively from September 2019 to October 2019, and the epithelial thicknesses of the cornea were obtained by AS-OCT and compared with control subjects who did not use contact lens. RESULTS: In total, 184 eyes (115 subjects) were included; of them, 75 eyes were keratoconic (KCN) and 109 eyes were nonkeratoconic (non-KCN). Twenty eyes in KCN and 79 eyes of non-KCN group had no history of contact lens use and were included for comparison with KCN and non-KCN contact lens users, respectively. Mean duration of contact lens wearing was 75.63±50.42 months. The epithelial thickness of non-KCN SCL group was thinner than that of non-KCN control subjects all over the cornea, whereas the epithelium of non-KCN HCL was thinner at central site as well as nasal and temporal paracentral and midperipheral areas. Epithelial thickness of the KCN HCL group was not different from the KCN control subjects in all sectors. The KCN SCCL group had thinner epithelium at nearly all peripheral sectors as well as inferior, inferotemporal, inferonasal, and nasal midperipheral sectors compared with KCN control subjects. CONCLUSION: The corneal epithelium was thinner at the peripheral zones in KCN SCCL users; at both peripheral and central zones in non-KCN SCL users and in central zones in non-KCN HCL users.


Assuntos
Lentes de Contato , Epitélio Corneano , Córnea , Estudos Transversais , Humanos , Tomografia de Coerência Óptica/métodos
8.
Eye Contact Lens ; 48(5): 222-227, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35333798

RESUMO

BACKGROUND AND OBJECTIVES: Congenital cataract is a condition compromising the eye's crystalline lens in infants and is usually diagnosed at birth. It can lead to irreversible vision loss if not promptly detected and treated, especially in unilateral cases. Nowadays, children with congenital cataracts can undergo surgical removal of their opacified crystalline lenses, and visual rehabilitation is mandatory to prevent deep amblyopia. Contact lenses, predominantly of rigid gas-permeable (GP) type, are gaining more popularity for this matter. METHOD: In this retrospective cohort study, unilateral aphakic children younger than 6 years referred to the Contact Lens Clinic at Farabi Eye Hospital from November 2011 to September 2019 were included. RESULTS: Seventy-six unilateral aphakic children with congenital cataracts (57.9% boys and 42.1% girls) rehabilitated with GP were studied. The mean age of diagnosis and referral to the contact lens clinic were 20.0±19.8 and 32.0±24.4 weeks, respectively, while the mean follow-up time was 12.44±26.28 months. The mean visual acuity for children capable of cooperating at the last follow-up was 0.98±0.62 log MAR. Among the participants, eight children (9.7%) were diagnosed as glaucoma suspects. The mean initial base curve and power of GP lenses were 7.86±0.39 mm and 23.29±5.52 diopters, respectively. Only 21 parents (27.6%) reported nonadherence to the scheduled part-time patch program. CONCLUSION: The results of this study showed GP-based optical treatment after early diagnosis, surgical removal of congenital cataracts, and a long-term close follow-up to be well tolerated by children and their parents, with acceptable parents' compliance and can thus be introduced as a safe and effective method to achieve desirable visual outcomes.


Assuntos
Afacia Pós-Catarata , Extração de Catarata , Catarata , Lentes de Contato , Afacia Pós-Catarata/terapia , Criança , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Retrospectivos
9.
J Food Sci Technol ; 58(11): 4185-4193, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34538903

RESUMO

ABSTRACT: The study was devoted to developing a novel synbiotic beverage based on with millet, rye and alfalfa sprouts with a mixed culture of Lactobacillus casei and Lactobacillus plantarum. In this regard, the influences of incorporated prebiotics inulin and oligofructose on probiotics viability during the refrigerated storage (4 ± 1 °C, 28 days) as well as under the simulated gastric condition were investigated. The characteristics such as microbial viability, physicochemical properties (viscosity, pH, titrable acidity and radical scavenging activity) and sensorial evaluation were assessed. The synbiotic beverage produced contained 108 CFU ml-1 for L. casei, with a good survival throughout the storage period (108 CFU ml-1) and L. plantarum at sufficient levels (106 CFU ml-1) after about 21 days. Inulin and oligofructose promoted the growth of the strains and their viability under cold storage while conferring higher sensory scores. In this context, the beverages demonstrated acceptable sensory attributes. The viability (bacterial survival) of over 55% for all the strains was achieved under simulated gastric condition. Therefore, the introduced fermented beverage was a good food matrix from the viability of probiotics as well as under the gastric condition and sensory characteristics.

10.
Iran J Pharm Res ; 20(1): 165-174, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34400950

RESUMO

In the current study, a liquid chromatography coupled mass detector was set up to detect and quantify 108 pesticide residues in rice samples. QuEChERS method was applied for sample preparation and different validation parameters were determined to ensure the suitability of the method. The calibration curves were linear in the concentration 0.01-1.00 mg/kg with a coefficient of determination (R2) of more than 0.990 for all compounds. Based on signal to noise studies, the calculated LODs and LOQs were 0.005-0.060 mg/kg and 0.018-0.199 mg/kg, respectively; and acquired mean recoveries at three spiked levels (0.025, 0.200 and 0.800 mg/kg) were 72% - 117% with RSD < 20%. The developed method was used to investigate the occurrence of the studied pesticides in 65 internal and 65 foreign rice samples. The results showed that 14 internal and 15 imported samples were found to be contaminated 12 pesticides in the amounts between 0.027 mg/kg to 0.078 mg/kg and 0.031 mg/kg to 0.081 mg/kg, respectively. According to the Iranian regulations, with the exception of nine prohibited pesticides for rice production in Iran, bioallethrin, cypermethrin, deltamethrin, flutriafol, foramsulfuron, imazalil, phosphamidon, TCMTB, and triasulfuron, three permitted pesticides, cinosulfuron, triadimenol, and tricyclazole, found in positive rice samples were below MRLs established by Iranian National Standard Organization (INSO).

11.
Food Sci Nutr ; 9(5): 2768-2778, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34026090

RESUMO

In this study, the physicochemical, mechanical, and antimicrobial activities of polyethylene (PE) films coated with peppermint (Menthol) and Origanum vulgare (Carvacrol) essential oil were evaluated. For this reason, PE films were coated with MC-HPMC solution containing different concentrations of menthol and carvacrol (0, 1, 1.5, and 2%), and mechanical, electromagnetic, barrier, and antimicrobial properties of all prepared films were examined. The obtained results demonstrated that by increasing the concentration of menthol and carvacrol in film coatings, tensile strength (from 36 to 23 MPa), water vapor permeability (from 12 to 11 g.m-1s-1Pa-1), and L* and b* indexes were decreased, while the oxygen permeability (OP) and elongation at break significantly were increased (p < .05). Increment of menthol and carvacrol concentration in PE film coating leads to an increase in the antimicrobial activity of films against Escherichia coli, Staphylococcus aureus, Listeria innocua, and Saccharomyces cervicea. Finally, the results obtained from this study demonstrated that PE film coated with high levels of carvacrol and menthol could be used as active antimicrobial packaging in the food packaging industry.

12.
Food Sci Nutr ; 7(3): 930-936, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30918635

RESUMO

In the present study, quinoa protein hydrolyzate was prepared using alcalase and pepsin enzymes. Then, the effect of different temperatures (40, 45, 50, and 55°C), periods of time (60, 120, 150, 180, and 210 min), and the ratio of enzyme to substrate (30, 60, and 90 Anson unit/kg protein) on degree of hydrolysis were examined. Also, the antioxidant activity was assessed using DPPH radical scavenging test, and investigated using a completely randomized design. According to results, the optimum condition to produce hydrolyzates with the highest degree of hydrolysis (24.65%) was 55°C, 210 min, with ratio of enzyme to substrate of 60 Anson unit/kg protein, The highest antioxidant activity (35.44) of protein hydrolyzed was achieved at 150 min, 50°C, and the ratio of enzyme to substrate 60 (Anson unit/kg protein). Moreover, there was no significant (p > 0.05) between the level of hydrolysis and the antioxidant activity was among different time and temperatures. In conclusion, the peptide derived from quinoa protein showed a sufficient antioxidant activity to be incorporated in food products.

13.
J Food Sci Technol ; 54(6): 1703-1710, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28559629

RESUMO

In this study a novel biodegradable edible film based on Alyssum homolocarpum seed gum (AHSG) was fabricated and characterized. Glycerol at three levels (25, 35, and 45% based on dried AHSG) as plasticizer were added. The microstructure and barrier, electromagnetic, mechanical, and thermal properties of the film were characterized. Results showed that permeability to both oxygen and water vapor, increased as the plasticizer content increased from 25 to 45%. The mechanical properties of AHSG films were comparable to those of polysaccharide films. Results showed that the glycerol content significantly decreased the glass-transition temperature of the film. The color measurement indicated that increasing the plasticizer content augmented the b* and L* values. Results of the field emission scanning electron microscopy revealed a uniform and smooth surface morphology and an absence of phase separation among the film compositions. The findings demonstrated that AHSG has the potential to fabricate edible films with enhanced quality characteristics.

14.
Stud Health Technol Inform ; 220: 124-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27046564

RESUMO

Keratoconus is a progressive non-inflammatory disease of the cornea. Rigid gas permeable contact lenses (RGPs) are prescribed when the disease progresses. Contact lens fitting and assessment is very difficult in these patients and is a concern of ophthalmologists and optometrists. In this study, a hierarchical fuzzy system is used to capture the expertise of experienced ophthalmologists during the lens evaluation phase of prescription. The system is fine-tuned using genetic algorithms. Sensitivity, specificity and accuracy of the final system are 88.9%, 94.4% and 92.6% respectively.


Assuntos
Algoritmos , Lentes de Contato , Sistemas de Apoio a Decisões Clínicas/organização & administração , Ceratocone/reabilitação , Ajuste de Prótese/métodos , Terapia Assistida por Computador/métodos , Lógica Fuzzy , Humanos , Ceratocone/diagnóstico , Aprendizado de Máquina , Modelos Genéticos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
15.
Int J Biol Macromol ; 66: 254-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24582935

RESUMO

The antimicrobial, mechanical and barrier properties and light transmission of sago starch film incorporated with different percentage of Betel leaf extract (5%, 10%, 20%, and 30%) were evaluated. With regard to mechanical properties, tensile strength decreased when the percentage of extract increased. Elongation at break (%) and seal strength (N/m) increased with increasing percentage of extract from 5% to 20%, while decreased for films containing 30% extract due to heterogeneity of films in this percentage. With regard to barrier properties, water vapour and oxygen barrier properties decreased in all samples when percentage of the extract increased. Antimicrobial activity of all the films increased against both Gram positive and Gram negative bacteria as percentage of Betel leaf extract increased, except for Psuedomonas aeruginosa, which was not susceptible at any percentage of the extract.


Assuntos
Antibacterianos/química , Areca/química , Extratos Vegetais/química , Folhas de Planta/química , Amido/química , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Permeabilidade , Extratos Vegetais/farmacologia , Solubilidade , Amido/farmacologia , Vapor , Resistência à Tração , Água/química
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