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1.
Sensors (Basel) ; 24(9)2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38732932

RESUMEN

In this paper, a 3D conformal meta-lens designed for manipulating electromagnetic beams via height-to-phase control is proposed. The structure consists of a 40 × 20 array of tunable unit cells fabricated using 3D printing, enabling full 360° phase compensation. A novel automatic synthesizing method (ASM) with an integrated optimization process based on genetic algorithm (GA) is adopted here to create the meta-lens. Simulation using CST Microwave Studio and MATLAB reveals the antenna's beam deflection capability by adjusting phase compensations for each unit cell. Various beam scanning techniques are demonstrated, including single-beam, dual-beam generation, and orbital angular momentum (OAM) beam deflection at different angles of 0°, 10°, 15°, 25°, 30°, and 45°. A 3D-printed prototype of the dual-beam feature has been fabricated and measured for validation purposes, with good agreement between both simulation and measurement results, with small discrepancies due to 3D printing's low resolution and fabrication errors. This meta-lens shows promise for low-cost, high-gain beam deflection in mm-wave wireless communication systems, especially for sensing applications, with potential for wider 2D beam scanning and independent beam deflection enhancements.

2.
Sensors (Basel) ; 23(5)2023 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-36904796

RESUMEN

Antennas that generate orbital angular momentum (OAM) have the potential to significantly enhance the channel capacity of upcoming wireless systems. This is because different OAM modes that are excited from a shared aperture are orthogonal, which means that each mode can carry a distinct stream of data. As a result, it is possible to transmit multiple data streams at the same time and frequency using a single OAM antenna system. To achieve this, there is a need to develop antennas that can create several OAM modes. This study employs an ultrathin dual-polarized Huygens' metasurface to design a transmit array (TA) that can generate mixed-OAM modes. Two concentrically-embedded TAs are used to excite the desired modes by achieving the required phase difference according to the coordinate position of each unit cell. The prototype of the TA, which operates at 28 GHz and has a size of 11 × 11 cm 2, generates mixed OAM modes of -1 and -2 using dual-band Huygens' metasurfaces. To the best of the authors' knowledge, this is the first time that such a low-profile and dual-polarized OAM carrying mixed vortex beams has been designed using TAs. The maximum gain of the structure is 16 dBi.

3.
Curr Microbiol ; 79(6): 159, 2022 Apr 13.
Artículo en Inglés | MEDLINE | ID: mdl-35416548

RESUMEN

The role of the most fungal endophytes in the host plant growth and production of metabolites under stress conditions is still unknown. Fungal endophytes occur in almost all plants to benefit the host plants exposed to biotic and abiotic stress. In the present work, we investigated salt (NaCl) stress alleviation capability of a fungal endophyte (Porostereum spadiceum-AGH786). The culture filtrate (CF: 1.5 mL.) of P. spadiceum-AGH786 contained IAA (158 µg/ml), SA (29.3 µg/ml), proline (114.6 µg/ml), phenols (167.4 µg/ml), lipids (71.4 µg/ml), sugar (133.2 µg/ml), flavonoids (105.04 µg/ml). Smaller amounts of organic acids, such as butyric acid (5.8 µg/ml), formic acid (2.34 µg/ml), succinic acid (2.02 µg/ml), and quinic acid (2.25 µg/ml) were also found in CF of P. spadiceum-AGH786. Similarly, the CF displayed antioxidant activity in 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-Azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS) assays. Moreover, wheat plants colonized by P. spadiceum-AGH786 showed significantly (P = 0.05) higher polyphenol oxidases activity (2.2 mg/g DW) under normal conditions as compared to the NaCl-treated plants. We also observed that P. spadiceum-AGH786 improved biomass (0.30 g) of wheat plants subjected to 140 mM NaCl stress. The results conclude that the wheat plant colonization by P. spadiceum-AGH786 greatly improved the plant growth under 70 mM and 140 mM NaCl stress. Thus, the biomass of the P. Spadiceum-AGH786 can be used in saline soil to help the host plants.


Asunto(s)
Polyporales , Triticum , Estrés Salino , Cloruro de Sodio/metabolismo , Triticum/metabolismo
4.
Molecules ; 27(9)2022 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-35566017

RESUMEN

In the present work, 0.25 wt%GNP-Ti composites were prepared through powder metallurgy route by adopting three types of mixing modes to investigate the extent of mixing on the mechanical and tribological properties. Dry ball milling, wet ball milling, and rotator mixing were independently employed to homogenize the composite constituents. Three types of composite powders obtained were subsequently sintered into composite pellets by cold compaction followed by vacuum sintering. Morphological investigation of composite powders performed by SEM revealed better homogenization of GNPs in Ti matrix for dry ball milled composite powder, whereas wet ball milled and rotator mixed composite powders showed aggregation and bundling of GNPs. Micro Vickers hardness of composites produced via dry ball milling is 4.56% and 15.7% higher than wet ball milled and rotator mixed samples, respectively. Wear test performed by pin-on-disk tribometer showed higher wear loss for wet ball milled and rotator mixed composites in comparison to dry ball milled.

5.
Molecules ; 27(9)2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35566341

RESUMEN

The corrosion of metals, i.e., the initiation and acceleration of the surface deterioration of metals through an electrochemical reaction with the surrounding intrusive environment, is a global concern because of the economic and environmental impacts. Corrosion inhibitors are considered the most practical choice among the available corrosion protection techniques due to their effectiveness in terms of functionality and cost. The use of traditional and toxic corrosion inhibitors has led to environmental issues, arousing the need for green counterparts that are environmentally friendly, easily accessible, biodegradable, and cost-effective. In this review, the utilization of green corrosion inhibitors purely acquired from renewable sources is explored, with an in-depth focus on the recent advancements in the use of fruit and vegetable extracts as green corrosion inhibitors. In particular, fruits and vegetables are natural sources of various phytochemicals that exhibit key potential in corrosion inhibition. To shed light on the true potential of such extracts in the protection of steel in acidic environments, the experimental techniques involved in corrosion inhibition and the mechanism of corrosion inhibition are discussed in detail. The study highlights the potential of fruit and vegetable extracts as non-toxic, economical, and effective corrosion inhibitors in the pursuit of green chemistry. In addition to discussing and outlining the current status and opportunities for employing fruit and vegetable extracts as corrosion inhibitors, the current review outlines the challenges involved in the utilization of such extracts in corrosion inhibition.


Asunto(s)
Frutas , Verduras , Corrosión , Extractos Vegetales , Acero
6.
World J Microbiol Biotechnol ; 37(11): 195, 2021 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-34651251

RESUMEN

Heavy metal contamination due to anthropogenic activities is a great threat to modern humanity. A novel and natural technique of bioremediation using microbes for detoxification of heavy metals while improving plants' growth is the call of the day. In this study, exposing soybean plants to different concentrations (i.e., 10 and 50 ppm) of chromium and arsenic showed a severe reduction in agronomic attributes, higher reactive oxygen species production, and disruption in the antioxidant system. Contrarily, rhizobacterial isolate C18 inoculation not only rescued host growth, but also improved the production of nonenzymatic antioxidants (i.e., flavonoids, phenolic, and proline contents) and enzymatic antioxidants i.e., catalases, ascorbic acid oxidase, peroxidase activity, and 1,1-diphenyl-2-picrylhydrazyl, lower reactive oxygen species accumulation in leaves. Thereby, lowering secondary oxidative stress and subsequent damage. The strain was identified using 16 S rDNA sequencing and was identified as Pseudocitrobacter anthropi. Additionally, the strain can endure metals up to 1200 ppm and efficient in detoxifying the effect of chromium and arsenic by regulating phytohormones (IAA 59.02 µg/mL and GA 101.88 nM/mL) and solubilizing inorganic phosphates, making them excellent phytostimulant, biofertilizers, and heavy metal bio-remediating agent.


Asunto(s)
Antioxidantes/metabolismo , Enterobacteriaceae/metabolismo , Glycine max/metabolismo , Glycine max/microbiología , Metales Pesados/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Arsénico/metabolismo , Arsénico/toxicidad , Biodegradación Ambiental , Cromo/metabolismo , Cromo/toxicidad , Enterobacteriaceae/efectos de los fármacos , Enterobacteriaceae/crecimiento & desarrollo , Enterobacteriaceae/aislamiento & purificación , Ácidos Indolacéticos/metabolismo , Metaboloma , Metales Pesados/toxicidad , Oxidación-Reducción , Estrés Oxidativo , Fosfatos/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Rizosfera , Contaminantes del Suelo/metabolismo , Contaminantes del Suelo/toxicidad , Glycine max/crecimiento & desarrollo
7.
J Pak Med Assoc ; 71(Suppl 7)(11): S67-S69, 2021 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-34793432

RESUMEN

INTRODUCTION: Crowdsourcing pools together dispersed information that is considered public knowledge in an area, to form realistic estimates about the area, or to identify new ideas. The technique can be extremely helpful to develop estimates of public health indicators such as catchment area populations or healthcare providers; however, such uses must be scientifically validated. METHODS: We divided the community into 1040 discrete segments of similar lengths of streets (called spots) and then randomly selected 605 of these spots for crowdsourcing. Local respondents were asked to estimate the maximum and the minimum population residing in those spots. Five informants were interviewed per spot. Median values for the maximum and minimum were averaged to arrive at an estimate for the spot's population. Estimates for all spots were added together to arrive at the population of the community. One hundred spots from the 597 crowdsourced spots were revisited to conduct a household census as a "gold standard". RESULTS: Spots where both crowdsourcing and census estimates were computed had a crowdsource population estimate of 19,255 versus a census estimate of 18,119 - a variation of 5.9% (p: <0.001). However, within spot variation was a mean of 25%. CONCLUSIONS: Crowdsourcing communities for public knowledge information can yield more accurate information about public health indicators such as populations. In turn these estimates can help to better understand public health programme coverage. Other applications to consider may be missed children for immunization or schooling, deaths or births in communities or to identify total formal or informal healthcare providers in a community.


Asunto(s)
Colaboración de las Masas , Niño , Humanos , Salud Pública
8.
J Pak Med Assoc ; 71(7): 1889-1892, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-34410268

RESUMEN

Hepatic venous outflow obstruction, due to hepatic venous thrombosis is the hallmark of Budd-Chiari Syndrome (BCS), a relatively uncommon disorder. The aim of this study was to explore imaging details and causes, and define invasive and non-invasive interventions for achieving successful portosystemic shunting (PSS). The variations in imaging topology and associated risk factors in BCS cases, diagnosed during the past 20 months, were studied. Of the 53 cases (32 males, 21 females; mean age: 34.4±13.5 years), 5 (9%) were Hepatitis-B virus (HBV) positive, 12 (23%) were HCV positive and 6 (11%) were co-infected, rest were negative. Imaging features included mottled cirrhotic hepatic parenchyma, thrombosed hepatic and portal-vein with or without IVC thrombosis, left lobe atrophy, caudate hypertrophy, splenomegaly, portosystemic varices and ascites. Three cases had subacute onset; two had acute while the rest were chronic BCS. The aetiology was: protein C, S and anti-thrombin deficiency in 24 (45%), JAK2 mutation in 3 (6%), lupus antibody with increased homocysteine levels in 5 (9%) and cryptogenic in 21 (40%) cases. Twelve cases were planned for liver transplantation, 20 were prepared to undergo TIPS, and the rest were optimised medically.


Asunto(s)
Síndrome de Budd-Chiari , Trasplante de Hígado , Adulto , Síndrome de Budd-Chiari/diagnóstico por imagen , Femenino , Humanos , Masculino , Persona de Mediana Edad , Vena Porta/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Adulto Joven
9.
Ecotoxicol Environ Saf ; 206: 111381, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-33011512

RESUMEN

Today's world needs to control the industrial pollution through smarter ways. Presently, we observed the capacity of soil borne fungi to digest Synozol Red HF-6BN and Synozol Black B. Initially, 86 fungal strains were isolated from soil samples randomly collected from industrial sites. Among these, 31 isolates were capable of dye decolorization on solid media, with SN12f and SN13a isolates showed the highest decolorization capacity. The dye decolorization by both strains was higher (80-95%), when incubated for 120 h under optimized conditions of pH, concentration, nutrient source and temperature. The dye (Synozol red HF-6BN and Synozol black B) decolorization by SN12f isolate was maximum (˃90%) at pH7, whereas the SN13a decolorized 90% of Synozol red HF-6BN and 89% of Synozol black B at pH3. The SN13a and SN12f isolates at 40 mg/L showed de-colorization of 94.71%, 81.4% (for Synozol red HF-6BN) and 90.5%, 84.4% (Synozol black B), respectively. Our isolates also mitigated the toxic effect of azo dyes on the growth of phosphate solubilizing soil bacteria. In fact, the untreated effluent showed toxic effects on the growth of beneficial bacterial by developing zone of inhibition (16.5 mm around Aeromonas spp., 14.5 mm around Sallmonella while 14.25 mm around Citrobacter spp). However, the fungal treated dye was unable to develop zone of inhibition. Laccase activity was positive for both of fungal isolates after incubation on Bassnell Hass Medium (0.0733 U/mL for SN12f and 0.0439 U/mL SN13a). Using molecular approaches (ITS region), SN12f was identified as Aspergillus nidulans, while SN13a as Aspergillus fumigatus. The current study showed that local fungal flora can reclaim the contaminated soils and support the agro-friendly micro-flora.


Asunto(s)
Compuestos Azo/metabolismo , Hongos/metabolismo , Microbiología del Suelo , Descoloración del Agua/métodos , Contaminantes Químicos del Agua/metabolismo , Aspergillus/aislamiento & purificación , Aspergillus/metabolismo , Compuestos Azo/toxicidad , Bacterias/efectos de los fármacos , Bacterias/crecimiento & desarrollo , Biodegradación Ambiental , Hongos/aislamiento & purificación , Concentración de Iones de Hidrógeno , Aguas Residuales/toxicidad , Contaminantes Químicos del Agua/toxicidad
10.
Sensors (Basel) ; 20(14)2020 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-32679659

RESUMEN

This work demonstrates an integrated multiple-input multiple-output (MIMO) antenna solution for Long Term Evolution (LTE) and Millimeter-Wave (mm-wave) 5G wireless communication services. The proposed structure is comprised of a two-element LTE MIMO antenna, and a four-element 5G MIMO configuration with rectangular and circular defects in the ground plane. For experimental validation, the proposed structure is fabricated on a Rogers RO4350B substrate with 0.76 mm thickness. The overall substrate dimensions are 75 mm × 110 mm. The proposed structure is capable of operating at 5.29-6.12 GHz (LTE 46 and 47 bands) and 26-29.5 GHz (5G mm-wave) frequency bands. Additionally, the measured peak gain of 5.13 and 9.53 dB is attained respectively for the microwave and mm-wave antennas. Furthermore, the analysis of the MIMO performance metrics demonstrates good characteristics, and excellent field correlation performance across the operating bands. Furthermore, the analysis of the Specific Absorption Rate (SAR) and Power Density (PD) at the lower frequency band (5.9 GHz) and PD only at mm-Wave frequency band (28 GHz) verifies that the proposed antenna system satisfies the international human safety standards. Therefore, the proposed integrated MIMO antenna configuration ascertains to be a potential contender for the forthcoming communication applications.

11.
Sensors (Basel) ; 20(24)2020 Dec 19.
Artículo en Inglés | MEDLINE | ID: mdl-33352800

RESUMEN

This article presents the detailed theoretical, simulation, and experimental analysis of a half-mode substrate integrated waveguide (HMSIW)-based multimode wideband filter. A third-order, semicircular HMSIW filter is developed in this paper. A semicircular HMSIW cavity resonator is adopted to achieve wide band characteristics. A U-shaped slot (acts as a λ/4 stub) in the center of a semicircular HMSIW cavity resonator and L-shaped open-circuited stubs are used to improve the out-of-band response by generating multiple transmission zeros (TZs) in the stop-band region of the filter. The TZs on either side of the passband can be controlled by adjusting dimensions of a U-shaped slot and L-shaped open-circuited stubs. The proposed filter covers a wide fractional bandwidth, has a lower insertion loss value, and has multiple TZs (which improves the selectivity). The simulated response of filter agrees well with the measured data. The proposed HMSIW bandpass filter can be integrated with any planar wideband communication system circuit, thanks to its planar structure.

12.
BMC Microbiol ; 19(1): 3, 2019 01 07.
Artículo en Inglés | MEDLINE | ID: mdl-30616522

RESUMEN

BACKGROUND: To combat salinity, plants need easily accessible, safe and sustainable mechanisms for optimum growth. Recently, endophytes proved to be the promising candidates that helped the host plant to thrive under stress conditions. Therefore, the aim was to discover endophytic strain(s) and their mechanism of action to alleviate salt stress in maize. RESULTS: Keeping the diverse role of endophytes in view, 9 endophytic fungi from the spines of Euphorbia milli L. were isolated. Among the isolated fungal isolates, isolate FH1 was selected for further study on the basis of high antioxidant activity and capability to produce high indole-3-acetic acid (IAA), indole-3-acetamide (IAM), phenol and flavonoid contents. The 18S rDNA sequence homology and phylogenetic analysis of the fungal isolate FH1 revealed to be Yarrowia lipolytica. Furthermore, the inoculation of Y. lipolytica FH1 had significantly promoted plant growth attributes in treated maize as compared to positive (salt stress) and negative (salt stress free) controls. Likewise, differences in chlorophyll, carotenes, electrolyte leakage, leaf relative water, peroxidase, catalase, ABA, IAA and proline contents were observed between treated maize and controls. Interestingly, Y. lipolytica FH1 inoculated plants showed lower endogenous ABA and higher endogenous IAA contents. CONCLUSION: From the results, we have concluded that Y. lipolytica inoculation has promoted the growth of maize plants through controlled metabolism and hormonal secretions (ABA and IAA) under salinity stress. Because of the fact, Y. lipolytica can be tried as an eco-friendly bio-fertilizer to achieve optimum crop productivity under saline conditions.


Asunto(s)
Endófitos/metabolismo , Interacciones Huésped-Patógeno/fisiología , Estrés Salino/fisiología , Yarrowia/metabolismo , Zea mays/microbiología , Ácido Abscísico/metabolismo , Ácidos Indolacéticos/metabolismo , Filogenia , ARN Ribosómico 18S/genética , Yarrowia/clasificación , Yarrowia/genética
13.
Biochem J ; 475(18): 2893-2905, 2018 09 18.
Artículo en Inglés | MEDLINE | ID: mdl-30127090

RESUMEN

Flooding is an abiotic stress that creates hypoxic conditions triggered by redox potential leading to restricted growth and grain yield in plants. In the current study, we have investigated the effect of exogenous gibberellins (GA4+7) on soybean under flooding stress. A regulatory role of GAs on biochemical changes in soybean plants [including chlorophyll contents, endogenous bioactive GA1 and GA4, endogenous jasmonic acid (JA) and abscisic acid (ABA)] has been elucidated after 3 and 6 h of flooding stress. The modulation of stress-related bio-chemicals and their genetic determinants [for instance, ABA (Timing of CAB expression1-TOC1, ABA-receptor-ABAR) and NO (S-nitrosoglutathione reductase-GSNOR1, NO overproducer1-NOX, and nitrite reductase-NR)] in response to short-term flooding stress were also explored. The current study showed that exogenous GAs rescued chlorophyll contents, enhanced endogenous bioactive GA1 and GA4 levels, endogenous jasmonic acid (JA) and checked the rate of ABA biosynthesis under short-term flooding. The exo-GAs induced the glutathione activity and reduced the resulting superoxide anion contents during short-term flooding in Pungsannamul soybean. Exo-GAs also triggered the endogenous S-nitrosothiols (precursor for increased NO production) that have been decreased over the time. Moreover, the exo-GAs could impinge a variety of biochemical and transcriptional programs that are ameliorative to plant growth during short-term flooding stress. The presence of GA1 and GA4 also confirms the presence of both C13-hydroxylation pathway and non-C13-hydroxylation pathway in soybean, respectively.


Asunto(s)
Giberelinas/farmacología , Glycine max/metabolismo , Estrés Fisiológico/efectos de los fármacos , Ácido Abscísico/metabolismo , Clorofila/metabolismo , Ciclopentanos/metabolismo , Oxilipinas/metabolismo
14.
Sensors (Basel) ; 19(6)2019 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-30909414

RESUMEN

A minimally-sized, triple-notched band ultra-wideband (UWB) antenna, useful for many applications, is designed, analyzed, and experimentally validated in this paper. A modified maple leaf-shaped main radiating element with partial ground is used in the proposed design. An E-shaped resonator, meandered slot, and U-shaped slot are implemented in the proposed design to block the co-existing bands. The E-shaped resonator stops frequencies ranging from 1.8⁻2.3 GHz (Advanced Wireless System (AWS1⁻AWS2) band), while the meandered slot blocks frequencies from 3.2⁻3.8 GHz (WiMAX band). The co-existing band ranging from 5.6⁻6.1 GHz (IEEE 802.11/HIPERLANband) is blocked by utilizing the U-shaped section in the feeding network. The notched bands can be independently controlled over a wide range of frequencies using specific parameters. The proposed antenna is suitable for many applications because of its flat gain, good radiation characteristics at both principal planes, uniform group delay, and non-varying transfer function ( S 21 ) for the entire UWB frequency range.

15.
Sensors (Basel) ; 19(5)2019 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-30857265

RESUMEN

A compact, cylindrical dielectric resonator antenna (CDRA), using radio frequency signals to identify different liquids is proposed in this paper. The proposed CDRA sensor is excited by a rectangular slot through a 3-mm-wide microstrip line. The rectangular slot has been used to excite the CDRA for H E M 11 mode at 5.25 GHz. Circuit model values (capacitance, inductance, resistance and transformer ratios) of the proposed CDRA are derived to show the true behaviour of the system. The proposed CDRA acts as a sensor due to the fact that different liquids have different dielectric permittivities and, hence, will be having different resonance frequencies. Two different types of CDRA sensors are designed and experimentally validated with four different liquids (Isopropyl, ethanol, methanol and water).

16.
J Food Sci Technol ; 54(9): 2973-2979, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28928538

RESUMEN

The aim of present study was to evaluate the different pomegranate cultivars for physicochemical properties and to identify the best cultivars suitable for food processing and future breeding. Various attributes of fruit (including length, weight and diameter), rind (thickness and weight), calyx (length), aril (weight, percentage, length and width), seed (length and width) and juice (titratable acidity and soluble solids or TSS) were evaluated. Total and reducing sugar, pH, ascorbic acid, total phenolic contents, antioxidant activity and maturity index were also evaluated. A significant difference in all tested parameters was noted amongst the tested cultivars except calyx length, rind thickness, arils and seed dimensions. The antioxidant activity and total phenolic contents of pomegranate cultivars were ranged from 15.77 to 42% and 1158.9 to 1540.7 mg GAE L-1. The cultivars Tor-390 and Sorkhak-859 were sweet in taste, while the rest of the cultivars have sweet sour taste. The study concluded that the majority of cultivars were rich source of total phenolics, ascorbic acid, total soluble solid and total sugars, which are beneficial to health. Some of the elite cultivars (NKP-561, SRK-296, SZR-385, SRK-878) showed high quality attributes and were suitable for future breeding programs.

17.
Ann Bot ; 117(4): 607-23, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26957370

RESUMEN

BACKGROUND AND AIMS: Cress-seed (Lepidium sativum) exudate exerts an allelochemical effect, promoting excessive hypocotyl elongation and inhibiting root growth in neighbouring Amaranthus caudatus seedlings. We investigated acidic disaccharides present in cress-seed exudate, testing the proposal that the allelochemical is an oligosaccharin-lepidimoic acid (LMA; 4-deoxy-ß-l-threo-hex-4-enopyranuronosyl-(1→2)-l-rhamnose). METHODS: Cress-seed exudate was variously treated [heating, ethanolic precipitation, solvent partitioning, high-voltage paper electrophoresis and gel-permeation chromatography (GPC)], and the products were bioassayed for effects on dark-grown Amaranthus seedlings. Two acidic disaccharides, including LMA, were isolated and characterized by electrophoresis, thin-layer chromatography (TLC) and nuclear magnetic resonance (NMR) spectroscopy, and then bioassayed. KEY RESULTS: Cress-seed exudate contained low-Mr, hydrophilic, heat-stable material that strongly promoted Amaranthus hypocotyl elongation and inhibited root growth, but that separated from LMA on electrophoresis and GPC. Cress-seed exudate contained ∼250 µmLMA, whose TLC and electrophoretic mobilities, susceptibility to mild acid hydrolysis and NMR spectra are reported. A second acidic disaccharide, present at ∼120 µm, was similarly characterized, and shown to be ß-d-xylopyranosyl-(1→3)-d-galacturonic acid (Xyl→GalA), a repeat unit of xylogalacturonan. Purified LMA and Xyl→GalA when applied at 360 and 740 µm, respectively, only slightly promoted Amaranthus hypocotyl growth, but equally promoted root growth and thus had no effect on the hypocotyl:root ratio, unlike total cress-seed exudate. CONCLUSIONS: LMA is present in cress seeds, probably formed by rhamnogalacturonan lyase action on rhamnogalacturonan-I during seed development. Our results contradict the hypothesis that LMA is a cress allelochemical that appreciably perturbs the growth of potentially competing seedlings. Since LMA and Xyl→GalA slightly promoted both hypocotyl and root elongation, their effect could be nutritional. We conclude that rhamnogalacturonan-I and xylogalacturonan (pectin domains) are not sources of oligosaccharins with allelochemical activity, and the biological roles (if any) of the disaccharides derived from them are unknown. The main allelochemical principle in cress-seed exudate remains to be identified.


Asunto(s)
Brassicaceae/metabolismo , Disacáridos/metabolismo , Glicósidos/metabolismo , Ácidos Hexurónicos/metabolismo , Pectinas/metabolismo , Feromonas/metabolismo , Exudados de Plantas/metabolismo , Semillas/metabolismo , Ácidos Urónicos/metabolismo , Bioensayo , Cromatografía en Gel , Cromatografía en Capa Delgada , Electroforesis , Calor , Interacciones Hidrofóbicas e Hidrofílicas , Hipocótilo , Espectroscopía de Resonancia Magnética , Peso Molecular , Ramnosa/metabolismo
18.
PLoS One ; 19(6): e0303890, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38843255

RESUMEN

Anomaly detection in time series data is essential for fraud detection and intrusion monitoring applications. However, it poses challenges due to data complexity and high dimensionality. Industrial applications struggle to process high-dimensional, complex data streams in real time despite existing solutions. This study introduces deep ensemble models to improve traditional time series analysis and anomaly detection methods. Recurrent Neural Networks (RNNs) and Long Short-Term Memory (LSTM) networks effectively handle variable-length sequences and capture long-term relationships. Convolutional Neural Networks (CNNs) are also investigated, especially for univariate or multivariate time series forecasting. The Transformer, an architecture based on Artificial Neural Networks (ANN), has demonstrated promising results in various applications, including time series prediction and anomaly detection. Graph Neural Networks (GNNs) identify time series anomalies by capturing temporal connections and interdependencies between periods, leveraging the underlying graph structure of time series data. A novel feature selection approach is proposed to address challenges posed by high-dimensional data, improving anomaly detection by selecting different or more critical features from the data. This approach outperforms previous techniques in several aspects. Overall, this research introduces state-of-the-art algorithms for anomaly detection in time series data, offering advancements in real-time processing and decision-making across various industrial sectors.


Asunto(s)
Redes Neurales de la Computación , Algoritmos , Análisis Multivariante , Aprendizaje Profundo , Factores de Tiempo
19.
Nat Prod Res ; : 1-6, 2024 Oct 08.
Artículo en Inglés | MEDLINE | ID: mdl-39377349

RESUMEN

In the current study, five fungal endophytes (WR-1, WR-2, WR-3, WR-4, WS-6) were isolated from the roots and stem of Withania somnifera (L.) Dunal, and tested fungal culture filtrates (FCF) against the brain tumour (glioblastoma) cell line (U-87). All FCFs showed anti-tumour activity with an IC50 value of 3.5, 6.0, 3.2, 6.0, and 0.95 µg/mL, respectively. HPLC fractionation of WS-6 showed the presence of 11 compounds (A1-A11), all with good anti-tumour activities (IC 50 3.5, 5.0, 5.0, 3.6, 2.5, 1.7, 2.3, 2.7, 0.9, 1.8 and 0.4 µg/mL, respectively). We report for the first time, the anti-tumour activity of 1-Docosene, Phenol, 2,4-bis(1,1-dimethylethyl), 1,2-Benzenedicarboxylic acid, diisooctyl ester, Hexadecane, 1,1-bis(dodecyloxy)-, Benzene, 1,1'-(2-methyl-2-(phenylthio)cyclopropylidene) bis-, Naphthalene, 1,2-dihydro-1-phenyl- (A1-A6), identified by GC-MS. The rest (A7-A11) had earlier reports of anticancer activities on cell lines other than U-87. We conclude that endophytic WS-6 (Aspergillus fumigatus) produces antitumor compounds that might be helpful in future drug development against brain tumours, especially glioblastoma.

20.
Food Chem (Oxf) ; 8: 100190, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-38259870

RESUMEN

Sugar and fatty acid content are among the important factors that contribute to the intensity of flavor in aromatic coconut. Gaining a comprehensive understanding of the sugar and fatty acid metabolites in the flesh of aromatic coconuts, along with identifying the key synthetic genes, is of significant importance for improving the development of desirable character traits in these coconuts. However, the related conjoint analysis of metabolic targets and molecular synthesis mechanisms has not been carried out in aromatic coconut until now. UPLC-MS/MS combined with RNA-Seq were performed in aromatic coconut (AC) and non-aromatic coconut (NAC) meat at 7, 9 and 11 months. The results showed that D-fructose in AC coconut meat was 3.48, 2.56 and 3.45 fold higher than that in NAC coconut meat. Similarly, D-glucose in AC coconut meat was 2.48, 2.25 and 3.91 fold higher than that in NAC coconut meat. The NAC coconut meat showed a 1.22-fold rise in the content of lauric acid compared to the AC coconut meat when it reached 11 months of age. Myristic acid content in NAC coconut meat was 1.47, 1.44 and 1.13 fold higher than that in AC coconut meat. The palmitic acid content in NAC coconut meat was 1.62 and 1.34 fold higher than that in AC coconut meat. The genes SPS, GAE, GALE, GLCAK, UGE, UGDH, FBP, GMLS, PFK, GPI, RHM, ACC, FabF, FatA, FabG, and FabI exhibited a negative correlation with D-fructose (r = -0.81) and D-glucose (r = -0.99) contents, while showing a positive correlation (r = 0.85-0.96) with lauric acid and myristic acid. Furthermore, GALE, GLCAK, FBP, GMLS, and ACC displayed a positive correlation (r = 0.83-0.94) with palmitic acid content. The sugar/organic acid ratio exhibited a positive correlation with SPS, GAE, UGE, FabF, FabZ and FabI.

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