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1.
Micromachines (Basel) ; 15(5)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38793224

RESUMO

In this paper, an irregular octagonal two-port MIMO patch antenna is designed specifically for New Radio (NR) 5G applications in the mid-band sub-6 GHz. The proposed antenna comprises an irregularly shaped patch antenna equipped with a regular 50-ohm feed line and a parasitic strip line antenna, and is partially grounded. Jeans material serves as a substrate with an effective dielectric constant of 1.6 and a thickness of 1 mm. This material is studied experimentally. The proposed antenna design undergoes analysis and optimization using the ANSYS HFSS tool. Furthermore, the design incorporates the influence of the slot on both the ground plane and the parasitic strip line to optimize performance, enhance isolation, and improve impedance matching among antenna elements. The dimensions of the jeans substrate are 40 mm × 50 mm. The simulated impedance bandwidth ranged from 3.6 GHz to 7 GHz and the measured bandwidth was slightly narrower, from 4.35 GHz to 7 GHz. The simulation results demonstrated an isolation level greater than 12 dB between antenna elements, while the measured results reached 28.5 dB, and the peak gain for this proposed antenna stood at 6.74 dB. These qualities made this proposed antenna suitable for various New Radio mid-band 5G wireless applications within the sub-6 GHz band, such as N79, Wi-Fi-5/6, V2X, and DSRC applications.

2.
Sci Rep ; 14(1): 5037, 2024 02 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424450

RESUMO

The filamentous Thermoascus aurantiacus fungus characterized by its thermophilic nature, is recognized as an exceptional producer of various enzymes with biotechnological applications. This study aimed to explore biotechnological applications using polygalacturonase (PG) derived from the Thermoascus aurantiacus PI3S3 strain. PG production was achieved through submerged fermentation and subsequent purification via ion-exchange chromatography and gel filtration methods. The crude extract exhibited a diverse spectrum of enzymatic activities including amylase, cellulase, invertase, pectinase, and xylanase. Notably, it demonstrated the ability to hydrolyze sugarcane bagasse biomass, corn residue, and animal feed. The purified PG had a molecular mass of 36 kDa, with optimal activity observed at pH 4.5 and 70 °C. The activation energy (Ea) was calculated as 0.513 kJ mol-1, highlighting activation in the presence of Ca2+. Additionally, it displayed apparent Km, Vmax, and Kcat values of at 0.19 mg mL-1, 273.10 U mL-1, and 168.52 s-1, respectively, for hydrolyzing polygalacturonic acid. This multifunctional PG exhibited activities such as denim biopolishing, apple juice clarification, and demonstrated both endo- and exo-polygalacturonase activities. Furthermore, it displayed versatility by hydrolyzing polygalacturonic acid, carboxymethylcellulose, and xylan. The T. aurantiacus PI3S3 multifunctional polygalacturonase showed heightened activity under acidic pH, elevated temperatures, and in the presence of calcium. Its multifunctional nature distinguished it from other PGs, significantly expanding its potential for diverse biotechnological applications.


Assuntos
Saccharum , Thermoascus , Poligalacturonase/metabolismo , Thermoascus/metabolismo , Celulose , Enzimas Multifuncionais , Saccharum/metabolismo , Concentração de Íons de Hidrogênio , Estabilidade Enzimática , Temperatura
3.
Braz J Microbiol ; 54(3): 1559-1564, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37440124

RESUMO

Denim, also known as jeans, is a fabric made up of braided cotton threads dyed indigo blue, whose fibers contain approximately 10% of non-cellulosic impurities that reduce its commercial value. Microbial enzymes can act in the cleaning and desizing processes of jeans, improving their color, softness, and covering capacity. The recombinant Xylanase II (XynA2) from the aquatic bacterial Caulobacter crescentus (C. crescentus), previously characterized in terms of its biochemical features, was applied to the biotreatment of jeans to clean and degum it. The biotreatment performance was evaluated in terms of tissue weight loss, amount of reducing sugars released and analysis of the images obtained by scanning electron microscopy (SEM). Biotreated tissues, at 12 and 24 h, showed a dry weight loss of 4.9 and 6.6%, respectively. The reducing sugars amount released after XynA2 action over the jean's fibers showed statistically significant values when compared with each other and with their respective controls. SEM images clearly shown that the fabric treated for 12 h presented a smooth and polished surface, while the fabric treated for 24 h showed the cotton fibers broken, displaying severe damage to the textile. The best treatment for the jeans was in the presence of 1 U mg-1 XynA2 at pH 8 and 60 °C during 12 h. In conclusion, XynA2 of C. crescentus was satisfactorily applied for the biopolishing of denim jeans being a more sustainable alternative to the use of chemical and abrasive processes to obtain the same effects.


Assuntos
Caulobacter crescentus , Caulobacter crescentus/genética , Têxteis , Fibra de Algodão , Índigo Carmim , Corantes
4.
Environ Sci Pollut Res Int ; 28(41): 58570-58582, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34115293

RESUMO

Microplastic particles are a burgeoning population crisis in the marine environment. This research examines the emission of microfibers from three different jeans (garments) during domestic washing. The jeans types, washing temperature, washing duration, spin speed, detergent types, and addition of conditioner are the main factors for this research work. The average length and diameter of the microfibers for the 100% PET jeans (jeans-P) has 7800 ± 4000 µm and 11.9±3.2 µm and for polyester/cotton jeans (jeans-PB) has 4900 ± 2200 µm 17.4±4.8 µm, respectively. The maximum microfiber released was observed in the rigorous washing treatment (90 min, 60°C, 1400 rpm, powder detergent with the presence of conditioner). The surmised number of microfibers discharged from the 1 kg wash load of jeans-P was calculated within the extent of 2300000-4900000 microfibers, and it is varied by the washing treatments.


Assuntos
Lavanderia , Plásticos , Microplásticos , Poliésteres , Têxteis
5.
Int J Occup Saf Ergon ; 26(2): 423-428, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29412069

RESUMO

This study collected maximum static lifting strength (MSLS) data from 13 males and 13 females at an exertion height of 10-100 cm above the floor (in 10-cm increments) in wearing athletic shorts and wearing jeans conditions. Knee angles were also examined when participants performed the MSLS tasks. Results showed that gender, pant type and exertion height significantly affected participants' MSLS and corresponding knee angle. The effect of wearing jeans primarily occurred at 10-40 cm; meanwhile, male participants tended to stoop while exerting force. This substantially decreased their MSLS (55 N). For female participants in this exertion height range, no significant difference was found in knee angles; accordingly, wearing jeans only slightly affected their MSLS. In summary, wearing jeans had a noticeable effect on the MSLS of male participants, who should be particularly careful when performing lifting tasks at a height of less than 50 cm above the floor.


Assuntos
Vestuário , Remoção , Esforço Físico/fisiologia , Suporte de Carga/fisiologia , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Fatores Sexuais , Adulto Jovem
6.
J Med Syst ; 43(6): 177, 2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31073787

RESUMO

In the field of medicinal applications, early / (Timely) detection of Breast cancer is a key diagnosing process which provides effective medical treatment and also reduces women mortality. Due to the advancement and growth of medical sciences, efficient antennas are needed for imaging, diagnosing and providing superior treatment to the patients. Since tumor is tiny in size at the early stage, the knowledge of its precise location is chiefly required. For this purpose several antennas with high accuracy are designed. Among them, Flexible antenna has several advantages compared to other antennas. The main advantage of flexible antenna is its simple construction, high gain and cost-efficiency. The proposed research work implements a novel flexible antenna for detection of early breast cancer, with and without tumor application. In the study, (for the sake of comprehensive analysis and accuracy / familiarity / simplicity), Jean material is used as dielectric substrate with dielectric constant 1.7. The flexible antennas are designed with a slot loaded over the patch and with ground plane that are made up of copper as the conducting material. The jeans cloth material with 1 mm thickness is considered as a substrate, which is to be placed on the breast surface. Co-axial feeding method is chosen for the proposed antenna which improves the antenna performance. In addition to this, the antenna is a wearable textile type designed for ISM (Industrial, Scientific and Medical) band 2.4 GHz applications. The antenna is simulated using HFSS (High Frequency Structure Spectrum) software. From the simulation analysis, Return loss (S11), Gain in dB, Radiation pattern, axial ratio (AR) and VSWR are obtained and analyzed. Finally, the simulation results are compared with the existing methodologies.


Assuntos
Neoplasias da Mama/diagnóstico , Detecção Precoce de Câncer/métodos , Tecnologia sem Fio/instrumentação , Algoritmos , Desenho de Equipamento , Feminino , Humanos , Software
7.
Environ Res ; 172: 310-318, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30825680

RESUMO

The concentration of a number of trace elements (Ag, Al, As, B, Ba, Be, Bi, Cd, Cr, Co, Cu, Fe, Mg, Mn, Mo, Ni, Pb, Sb, Sc, Se, Sm, Sr, Sn, Tl, Ti, V and Zn) were determined in 42 commercialized denim garments (jeans and shirts), being dermal exposure subsequently assessed. Migration experiments with artificial acid and basic sweat were also conducted to determine the release of these elements, as well as indigo dye. In a similar way than for the total content, Mg (124 and 99.4 µg/g) and Mn (27.1 and 7.20 µg/g) showed the highest concentrations in both artificial sweat, acid and basic, respectively. Indigo dye migrated at levels ranged from 3.22 to 7.76 mg/g, being higher in dark than in light blue fabrics. The levels of trace elements and indigo were analysed according to materials of fabric, colour, brand, and eco-labelling. Using total content and migrations rates, dermal exposure to trace elements for adult men, women and teenagers were calculated under the two sweat extractions. Non-carcinogenic and carcinogenic risks due to dermal exposure to the elements here analysed in cloths were assessed. Both risks were in the limits of safe to according to international regulations. However, the maximum exposure to Sb reached a hazard quotient (HQ) of 0.3 in clothes partially made of polyester. Despite some authors have established that indigo is an agonist of the aril receptor, health risks due to exposure to indigo dye were not calculated due the lack of toxicological data.


Assuntos
Exposição Ambiental , Índigo Carmim , Suor , Oligoelementos , Adolescente , Adulto , Feminino , Humanos , Índigo Carmim/metabolismo , Masculino , Medição de Risco , Suor/química , Oligoelementos/análise , Oligoelementos/metabolismo
8.
Waste Manag Res ; 32(11): 1142-4, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25245293

RESUMO

Because the insight is raising that waste prevention needs an integral product chain approach, a product chain project was awarded with an International Solid Waste Association grant. The project decided to focus on jeans because of the large environmental impacts of cotton and the low recycling rates. The project used an open innovative approach by involving many actors from the different phases of the chain and included student and applied researchers. In a 'design jeans for recycling' students' workshop, prototypes of jeans that are easier to recycle have been developed. Integrating the new generation from different disciplines in the project proved to be very successful. The results show that an open innovation process can lead to very creative ideas and that lessons learned from this project could be used to develop new chain projects for other products. An important condition is that key actors are willing to cooperate in an open innovation approach.


Assuntos
Vestuário , Comércio , Reciclagem , Monitoramento Ambiental , Países Baixos
11.
Forensic Sci Int ; 233(1-3): 283-7, 2013 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-24314531

RESUMO

Sharp force violence is a common way of committing assault in numerous countries and regions around the world. When a stabbing occurs, the clothing worn by the victim may provide vital evidence: for example the weapon used to stab the victim may be identified from severance in the clothing. However, whether laundering the clothing after an attack affects the severance morphology of the fabric and fibres, and whether identification of the weapon is possible from the severance in the clothing after laundering is not known. This study focussed on the effect of laundering 100% cotton twill weave (drill) and single jersey (knit) fabrics. Specimens had been pre-treated and stabbed with either a kitchen knife or a Phillips screwdriver. These specimens were photographed and were again laundered for one wash cycle before being photographed again. Ten expert judges compared the photographs taken before and after laundering. A difference in the appearance of the fabrics before and after laundering was evident. The morphology of the fabric and fibres thus would be expected to differ after laundering the clothing, making identification of a weapon used to stab through clothing more difficult.

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