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1.
RSC Adv ; 14(27): 19322-19330, 2024 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-38887647

RESUMEN

A significant amount of dye runoff and aqueous waste are released from the manufacturing process of dyes with intense and permanent colors, which are undesirable from a cultural and ecological aspect. In this paper, we present a green, simple, low-effort, and energy-efficient method of creating magnetized cubic Zn-MOFs for the adsorption and elimination of various organic dyes. Magnetic iron oxide materials with a hierarchical structure were loaded and doped into cubic zinc metal-organic frameworks (MDLZ). High magnetic characteristics, chemical stability, minimal toxicity, and ease of removing various dyes from aqueous effluents are all exhibited by the developed MDLZ adsorbent. To assess MDLZ's capacity to adsorb organic dyes from an aqueous solution, organic dyes such as Crystal Violet (CV), Neutral Red (NR), and Congo Red (CR) were used as model materials. Many adsorption factors were examined, including temperature, pH, contact time, initial concentration, and adsorbent dosage. Under optimal elimination circumstances, MDLZ was utilized to evaluate the kinetic, thermodynamic, and isotherm models for the adsorption of CR, NR, and CV dyes. The adsorption capacity (q m) of the MDLZ adsorbent at 25 °C was 39.37 mg g-1 for CV, 239.81 mg g-1 for CR, and 321.54 mg g-1 for NR, which is significantly higher than those of other adsorbents reported. The magnetized nanocubes' large surface area and uniform micropores enabled them to eliminate a large number of organic dyes from wastewater effectively, and their strong adsorption capability persisted even after four reuse cycles. The microporous MLDZ adsorbent offers a simple and effective method for handling industrial effluents and filtration of water.

2.
Opt Express ; 32(9): 16027-16039, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38859240

RESUMEN

We present the theory and experimental results of a microwave photonic (MWP) filter based instantaneous frequency measurement system. A quantum dash mode-locked laser is used as an optical frequency comb source. With up to 41 flat comb lines and a real-time feedback loop for comb shaping, a set of MWP filters with linear frequency responses for either linear unit or dB unit are experimentally demonstrated. The maximum measurement frequency can be up to 20 GHz limited by the available test-and-measurement instruments. By using one MWP filter, the root-mean-square error is 51∼66 MHz, which can be improved to 42.2 MHz for linear unit, and 30.7 MHz for dB unit by using two MWP filters together.

4.
Sci Rep ; 14(1): 9061, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38643227

RESUMEN

The indirect dumping of massive volumes of toxic dyes into water has seriously affected the ecosystem. Owing to the many applications of the designed nanomaterials in the manufacturing process, there is a lot of research interest in synthesizing nanomaterials using green processes. In this research, the byproduct of bee was employed to synthesize nanoparticles (NPs) of ZnO, CuO, and biosynthesized ZnO/CuO (BZC) nanocomposite via utilizing a green and simple approach. To validate the effective fabrication of BZC nanocomposite, various characterization measurements were applied. FTIR analysis identified the functional groups in charge of producing nanoparticles and nanocomposites. Moreover, the existence of ZnO and CuO XRD peaks suggests that the nanocomposites were successfully biosynthesized. The high-resolution XPS spectrum of the BZC nanocomposite's Zn2p3, Cu2p3, and O1s were observed. Our findings indicate the successful engineering of the prepared nanomaterials and BZC nanocomposite. Our findings indicate the successful engineering of the prepared nanomaterials and BZC nanocomposite. For Congo red (CR) fluorescent stain azo dye elimination in water, all adsorption parameters were examined at room temperature. Moreover, the adsorption experiments revealed the removal capacity for uptake CR dye using BZC nanocomposite (90.14 mg g-1). Our results show that the BZC nanocomposite exhibited high removal capability for the adsorption of CR dye. The nanosphere adsorbent offered a simple, low-cost, and green approach for water purification and industrial wastewater control.

5.
Ann Vasc Surg ; 105: 265-274, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38599493

RESUMEN

BACKGROUND: Venous ulcers are a late and severe form of chronic venous insufficiency and account for 70% of all etiologies that cause leg ulcers in the lower limb, and they account for 20% of the 2.5 million cases complaining of chronic venous disease. Our study aims to investigate the effect of venous stenting of the deep veins on the healing of the venous ulcer. METHODS: This is a single-center, retrospective study conducted on prospectively recorded medical records of 78 patients with chronic deep venous diseases-C6 (either nonocclusive iliac venous lesion or post-thrombotic syndrome). Our lesion involved May-Thurner lesions, occlusions, insufficiencies, or stenoses owing to an affection of the venous outflow segment. All our patients underwent endovascular management, and those who did not respond successfully were transitioned to compression therapy. We then compared the outcomes of both groups in terms of ulcer healing and quality of life. RESULTS: A total of 78 patients (78 limbs), with a mean age of 39.6 ± 8.06 (range: 22-60) years, were treated. Fifty-four patients (67.9%) were males, and 24 (32.1%) were female. The etiology was primary nonocclusive iliac venous lesion in 12 limbs (16.2%) and secondary post-thrombotic obstructions in 66 (83.7%). Follow-up of the ulcer with compliance to compression therapy and standard care of the ulcer, sustained ulcer healing (reduction in ulcer area) was achieved in 60% of limbs, and most of the nonocclusive healing occurred within the first 3 months (P < 0.01). CONCLUSIONS: Our results show that deep venous stenting is associated with high wound healing rates. This rate reaches a statistically significant difference in 3 months, but this difference doesn't reach statistical significance at 6 months, with less recurrence and improved quality of life with a high cumulative patency rate, and compression therapy is the mainstay of the conservative management of venous ulceration.


Asunto(s)
Procedimientos Endovasculares , Calidad de Vida , Stents , Úlcera Varicosa , Cicatrización de Heridas , Humanos , Femenino , Masculino , Persona de Mediana Edad , Úlcera Varicosa/terapia , Úlcera Varicosa/fisiopatología , Úlcera Varicosa/etiología , Estudios Retrospectivos , Adulto , Resultado del Tratamiento , Factores de Tiempo , Adulto Joven , Procedimientos Endovasculares/instrumentación , Procedimientos Endovasculares/efectos adversos , Síndrome Postrombótico/etiología , Síndrome Postrombótico/terapia , Síndrome Postrombótico/fisiopatología , Síndrome Postrombótico/diagnóstico por imagen , Enfermedad Crónica , Vena Ilíaca/diagnóstico por imagen , Vena Ilíaca/fisiopatología , Grado de Desobstrucción Vascular
6.
Opt Express ; 32(1): 217-229, 2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38175050

RESUMEN

We investigate the capabilities and limitations of quantum-dash mode-locked lasers (QD-MLLDs) as optical frequency comb sources in coherent optical communication systems. We demonstrate that QD-MLLDs are on par with conventional single-wavelength narrow linewidth laser sources and can support high symbol rates and modulation formats. We manage to transmit 64 quadrature amplitude modulation (QAM) signals up to 80 GBd over 80 km of standard single-mode fiber (SSMF), which highlights the distinctive phase noise performance of the QD-MLLD. Using a 38.5 GHz (6 dB bandwidth) silicon photonic (SiP) modulator, we achieve a maximum symbol rate of 104 GBd with 16QAM signaling and a maximum net rate of 416 Gb/s per carrier in a single polarization setup and after 80 km-SSMF transmission. We also compare QD-MLLD performance with commercial narrow-linewidth integrable tunable laser assemblies (ITLAs) and explore their potential for use as local oscillators (LOs) and signal carriers. The QD-MLLD has 45 comb lines usable for transmission at a frequency spacing of 25 GHz, and an RF linewidth of 35 kHz.

7.
J Hazard Mater ; 465: 133271, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38141313

RESUMEN

The extraordinary accumulation of cyanide ions within biological cells is a severe health risk. Detecting and tracking toxic cyanide ions within these cells by simple and ultrasensitive methodologies are of immense curiosity. Here, continuous tracking of ultimate levels of CN--ions in HeLa cells was reported employing biocompatible branching molecular architectures (BMAs). These BMAs were engineered by decorating colorant-laden dendritic branch within and around the molecular building hollows of the geode-shelled nanorods of organic-inorganic Al-frameworks. Batch-contact methods were utilized to assess the potential of hollow-nest architecture for inhibition/evaluation of toxicant CN--ions within HeLa cells. The nanorod BMAs revealed significant potential capabilities in monitoring and tracking of CN- ions (88 parts per trillion) in biological trials within seconds. These results demonstrated sufficient evidence for the compatibility of BMAs during HeLa cell exposure. Under specific conditions, the BMAs were utilized for in-vitro fluorescence tracking/sensing of CN- in HeLa cells. The cliff swallow nest with massive mouths may have the potential to reduce the health hazards associated with toxicant exposure in biological cells.


Asunto(s)
Estructuras Metalorgánicas , Humanos , Células HeLa , Iones , Cianuros , Sustancias Peligrosas
8.
Sci Rep ; 13(1): 21820, 2023 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-38071356

RESUMEN

Nowadays, dealing with the growing chemical and energy demands is important without compromising the environment. So, this work studies photocatalytic glycerol conversion (as biomass derivativ feedstock) into value-added products using an eco-friendly synthesized catalyst. Graphene quantum dots (GQDs) were prepared from available/cheap precursors like glucose via the hydrothermal method and used as a support for TiO2. TiO2/GQDs were characterized via different analytical techniques, revealing very small particle sizes of ~ 3-6 nm with a large surface area of ~ 253 m2/g and a band gap of ~ 2.6 eV. The prepared photocatalyst shows good efficiency during photocatalytic glycerol conversion to dihydroxyacetone (DHA). Different reaction conditions were tested: reaction time, catalyst amount, presence of oxidant (H2O2), and biphasic media (aqueous/organic phases). Comparing a monophasic (H2O) photoreactor with a biphasic reactor containing 90% organic phase (ethyl acetate) and 10% aqueous phase (H2O and/or H2O2) indicates that the presence of H2O2 increases glycerol conversion and liquid selectivity to reach 57% and 91%, respectively after 120 min. However, it still suffers a low DHA/GA ratio (2.7). On the other hand, using a biphasic reactor in the presence of an H2O2 oxidant increases the DHA/GA ratio to ~ 6.6, which was not reached in previous research. The formation of H2O/H2O2 as micro-reactors dispersed in the ethyl acetate phase increased the average light intensity effect of the glycerol/photocatalyst system in the micro-reactors. Unlike previous work, this work presents a facile way to prepare eco-friendly/cheap (noble metal free) photocatalysts for glycerol conversion to ultrapure DHA using a biphasic photoreactor.

9.
Appl Opt ; 62(32): 8696-8701, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-38037987

RESUMEN

We demonstrate photonic beamforming using a quantum-dash (QD) optical frequency comb (OFC) source. Thanks to the 25 GHz free spectral range (FSR) and up to 40 comb lines available from the QD OFC, we can implement phased antenna arrays (PAAs) with directional radiation and scanning. We consider two types of PAAs: a uniform linear array (ULA) and a uniform planar array (UPA). By selecting different comb lines with a programmable optical filter, we can tune the FSR of the OFC source and realize a discrete scanning function. We evaluate the beam squint of the ULAs, and the results show that we can achieve broadband operation. Finally, we show that we can achieve both directional radiation and scanning simultaneously using the UPA.

10.
Water Res ; 245: 120667, 2023 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-37778084

RESUMEN

Nitrous oxide (N2O) emissions may account for up to 80 % of a wastewater treatment plant's (WWTP) total carbon footprint. Given the complexity of the pathways involved, estimating N2O emissions through mechanistic models still often fails to precisely depict process dynamics. Alternatively, data-driven methods for predicting N2O emissions hold substantial potential. However, so far, a comprehensive approach is still overlooked, impeding the advancement of full-scale application. Therefore, this study develops a comprehensive approach for using machine learning to perform online process modeling of N2O emissions. The approach is tested on a long-term N2O emission dataset from a full-scale WWTP. Uniquely, the proposed approach emphasizes not just model accuracy, but it also considers model complexity, computational speed, and interpretability, equipping operators with the insights needed for informed corrective actions. Algorithms with varying levels of complexity and interpretability including k-Nearest Neighbors (kNN), decision trees, ensemble learning models, and deep neural networks (DNN) were considered. Furthermore, a parametric multivariate outlier removal method was adjusted to account for data statistical distributions, significantly reducing data loss. By employing an effective feature selection methodology, a trade-off between data acquisition, model performance, and complexity was found, reducing the number of features by 40 % and decreasing data collection cost, model complexity and computational burden without significant effect on modeling accuracy. The best performing models are kNN (R2 = 0.88), AdaBoost (R2 = 0.94), and DNN (R2 = 0.90). Feature importance of models was analyzed and compared with process knowledge to test interpretability, guiding N2O mitigation decisions.


Asunto(s)
Aguas Residuales , Purificación del Agua , Óxido Nitroso/análisis , Reactores Biológicos , Purificación del Agua/métodos , Aprendizaje Automático
11.
Urol Ann ; 15(3): 271-277, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37664098

RESUMEN

Background: Tubularized incised plate (TIP) is the most common technique used for distal hypospadias repair with good outcome but with a high rate of urethral stricture. Inner preputial-free graft can be used as an inlay graft in the incised area of the narrow urethral plate, also can be used as an onlay graft for urethroplasty in hypospadias repair to avoid this complication. Patients and Methods: A comparative prospective randomized study was conducted on two groups of hypospadias patients with narrow urethral plate. Group A: dorsal inlay inner preputial graft repair was performed (grafted TIP [G-TIP]) and Group B: ventral onlay preputial graft repair was performed. The assessment of outcome and hypospadias objective scoring evaluation (HOSE) score was done at 2 weeks and 6 months. Results: Group A included 55 patients for whom dorsal inlay inner preputial graft repair was performed (G-TIP), and Group B which was planned to be conducted on 55 patients using onlay preputial graft (onlay graft) but was terminated after 15 cases due to high failure rate (33%). Group A showed better success rate 96% and better HOSE score (score 16) at 2 months and 6 months 83.6% and 88.2% versus 26.7% and 33.3% in Group B. Postoperative complications showed a statistically significant difference; glans dehiscence (3.6% vs. 40%), wound infection (1.8% vs. 33.3%), and skin sloughing (3.6% vs. 26.7%) in Groups A and B, respectively. Conclusion: G-TIP is a good technique for the management of distal hypospadias with narrow urethral plate with good success rate, cosmetic outcome, and with less complications compared to onlay graft.

12.
Sci Rep ; 13(1): 12965, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37563146

RESUMEN

Optical layer attacks on optical fiber communication networks are one of the weakest reinforced areas of the network, allowing attackers to overcome security software or firewalls when proper safeguards are not put into place. Encrypting data using a random phase mask is a simple yet effective way to bolster the data security at the physical layer. Since the interactions of the random phases used for such encryption heavily depend on system properties like data rate, modulation format, distance, degree of phase randomness, laser properties, etc., it is important to determine the optimum operating conditions for different scenarios. In this work, assuming that the transmitter and the receiver have a secret pre-shared key, we present a theoretical study of security in such a system through mutual information analysis. Next, we determine operating conditions which ensure security for 4-PSK, 16-PSK, and 128-QAM formats through numerical simulation. Moreover, we provide an experimental demonstration of the system using 16-QAM modulation. We then use numerical simulation to verify the efficacy of the encryption and study two preventative measures for different modulation formats which will prevent an eavesdropper from obtaining any data. The results demonstrate that the system is secure against a tapping attack if an attacker has no information of the phase modulator and pre-shared key.

13.
Opt Lett ; 48(14): 3661-3664, 2023 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-37450719

RESUMEN

To develop an adaptive modulation scheme for flexible high-speed multi-user visible light communication (VLC), automatic modulation classification (AMC) is adopted for monitoring the modulation formats of different subcarrier groups. An AMC scheme based on a joint convolutional neural network (CNN), active learning (AL), and data augmentation (DA) is demonstrated over an orthogonal frequency division multiplexing access (OFDMA) VLC system. The configuration of the diffuse white-light VLC system is combined with a pair integrated transceiver module, a light-diffusing fiber (LDF), and a wireless channel, which can provide white-light illumination and ubiquitous access. Within the forward error correction (FEC) threshold, the data rates of the white-light VLC links can reach 325.5 Mbps with a bit error rate (BER) of 2.163 × 10-3. An experiment with two-user access via the proposed VLC link with an unequal bandwidth allocation was demonstrated. The performance of the AL-aided CNN AMC scheme also shows a classification accuracy rate of 95.48% for the constellation diagrams of different subcarriers of the OFDMA signal over 240 training samples and faster convergence than a CNN-based AMC.


Asunto(s)
Luz , Iluminación , Difusión , Redes Neurales de la Computación
14.
Environ Sci Pollut Res Int ; 30(35): 83810-83820, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37351750

RESUMEN

Prochloraz and tebuconazole are well-known fungicides for broad applications, including medical, industrial, and agricultural. They are frequently used simultaneously which increases the probability of their co-existing in various water sources. In this study, the analysis of PCZ or TBZ in water was performed by a direct analysis using the liquid chromatography-tandem mass spectrometry technique (LC-MS/MS). The optimized method was fully validated according to the European guidelines, SANTE/11312/2021. The complete degradation of these fungicides (each of 2 mg/L) in their single presence in the water was accomplished just after 15 min using 4.2 mM persulfate at 50 °C, while a lower concentration of persulfate (1.4 mM) leads to a degradation of prochloraz and tebuconazole, in their single existence in water, at percentages of 97 % and 98 %, respectively, after 30 min at 50 °C. On the other hand, it takes a complete hour to degrade a mixture of prochloraz and tebuconazole at percentages of 99 % and 94 %, respectively, using 1.4 mM persulfate at 50 °C. Degradation products (DPds) of prochloraz and tebuconazole, either in their single or simultaneous existing in water, were also identified and monitored during the whole degradation process by LC-MS/MS using at least two mass transitions for each DPd at both positive and negative ionization modes. It was elucidated that the persulfate degradation of prochloraz was conducted by the cleavage of the imidazole ring and the subsequent formation of a trichlorophenol, while persulfate degradation of tebuconazole was mainly accomplished by the formation of a hydroxyl structure, cleavage of the tert-butyl chain, and the subsequent formation of a ketone structure. Furthermore, a new DPd of tebuconazole (m/z = 263 Da) with a diketone structure was identified and confirmed.


Asunto(s)
Fungicidas Industriales , Espectrometría de Masas en Tándem , Cromatografía Liquida/métodos , Espectrometría de Masas en Tándem/métodos , Fungicidas Industriales/análisis , Imidazoles/análisis
15.
Acta Trop ; 244: 106952, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37236335

RESUMEN

Schistosomiasis is one of the most important neglected tropical diseases in Africa, caused by blood fluke, Schistosoma sp. The use of nanotechnology in the treatment of this type of disease is urgently important to avoid the unwanted side effects of chemotherapy. The present study aimed to evaluate the efficacy of green silver nanoparticles (G-AgNPs), fabricated by (Calotropis procera), comparing with both chemically prepared silver ones (C-AgNPs) and Praziquantel (PZQ) treatments. The study included in vitro and in vivo evaluations. In in vitro study, 4 groups of schistosome worms were exposed to treatments as follows: the first one with a dose of PZQ (0.2 µg/ml), the 2nd and 3rd groups with different concentrations of G-AgNPs and C-AgNPs, respectively and the last one act as a negative control group. In in vivo study, six groups of mice were infected and then treated as follows: the first one with a dose of PZQ, the second with G-AgNPs, the third with C-AgNPs, the fourth with G-AgNPs plus a half dose of PZQ, the fifth with C-AgNPs accompanied by a half dose of PZQ, and the last group acted as a positive control group. The parasitological (worm burden, egg count & oogram) and histopathological parameters (hepatic granuloma profile) were used to evaluate antischistosomal activities in experimental groups. Additionally, the subsequent ultrastructural alterations were observed in adult worms using scanning electron microscopy (SEM). Transmission electron microscopy analysis showed that G-AgNPs and C-AgNPs have 8-25 and 8-11 nm in diameter, respectively, besides, fourier transform infrared analysis (FTIR) revealed the presence of organic compounds (aromatic ring groups) which act as capping agents around the surfaces of biogenic silver nanoparticles. In in vitro experiment, adult worms incubated either with G-AgNPs or C-AgNPs at concentrations higher than 100 µg/ml or 80 µg/ml, respectively, showed full mortality of parasites after 24 h. In the infected treated groups (with G-AgNPs plus PZQ & C-AgNPs plus PZQ) showed the most significant reduction in the total worm burdens (92.17% & 90.52%, respectively). Combined treatment with C-AgNPs and PZQ showed the highest value of dead eggs (93,6%), followed by G-AgNPs plus PZQ-treated one (91%). This study showed that mice treated with G-AgNPs plus PZQ significantly has the highest percentage of reduction in granuloma size and count (64.59%, 70.14%, respectively). Both G-AgNPs plus PZQ-treated & C-AgNPs plus PZQ treated groups showed the highest similar values of reduction percentage of total ova count in tissues (98.90% & 98.62%, respectively). Concerning SEM, G-AgNPs-treated worms showed more variability in ultrastructural alterations than G-AgNPs plus PZQ-treated one, besides, worms treated with C-AgNPs plus PZQ exhibited the maximum level of contractions or (shrinkage) as a major impact.


Asunto(s)
Antihelmínticos , Nanopartículas del Metal , Schistosomatidae , Esquistosomiasis mansoni , Animales , Ratones , Esquistosomiasis mansoni/tratamiento farmacológico , Schistosoma mansoni , Plata/farmacología , Modelos Animales de Enfermedad , Praziquantel/uso terapéutico , Granuloma/patología , Antihelmínticos/uso terapéutico
16.
Environ Sci Pollut Res Int ; 30(26): 69514-69532, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37138129

RESUMEN

The present work focuses on the photocatalytic degradation of methylene blue (MB) on erbium ion (Er3+) doped TiO2 under visible light. Pure TiO2 nanoparticles and erbium (Er3+) doped TiO2 nanocomposite (Er3+/TiO2) NCs were synthesized using the sol-gel method. The synthesized (Er3+/TiO2) NCs were characterized using Fourier transform infrared spectroscopy (FTIR), high resolution scanning electron microscopy (HR-SEM), elementary dispersive X-ray (EDX), X-ray diffraction (XRD), and X-ray photoelectron spectra (XPS), specific surface area (BET), zeta potential, and particle size. Different parameters were used to study their efficiency for the photoreactor (PR) and the synthesized catalyst. These parameters include pH of the feed solution, the rate of flow, the presence of an oxidizing agent (aeration pump), different ratios of nanoparticles, the amount of catalyst, and the concentrations of pollutants. An example of an organic contaminant was the dye methylene blue (MB). The result achieved using the synthesized nanoparticles (I) under ultraviolet light pure TiO2 was found to have degraded by 85%. For (Er3+/TiO2) NCs under visible light, dye removal increased with pH to a maximum of 77% degradation at pH 5. Furthermore, photocatalytic efficiency improves to 80% at 40 rpm (3 l/h) low motor speed. The degradation efficiency decreased to 70% when the MB concentration was increased from 5 to 30 mg/L. When oxygen content was increased using an air pump, and deterioration reached 85% under visible light, it improved performance.


Asunto(s)
Metales de Tierras Raras , Nanopartículas , Azul de Metileno/química , Erbio , Luz , Titanio/química , Nanopartículas/química , Catálisis
17.
Front Psychiatry ; 14: 976921, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36911109

RESUMEN

Introduction: Synapses and spines play a significant role in major depressive disorder (MDD) pathophysiology, recently highlighted by the rapid antidepressant effect of ketamine and psilocybin. According to the Bayesian brain and interoception perspectives, MDD is formalized as being stuck in affective states constantly predicting negative energy balance. To understand how spines and synapses relate to the predictive function of the neocortex and thus to symptoms, we used the temporal memory (TM), an unsupervised machine-learning algorithm. TM models a single neocortical layer, learns in real-time, and extracts and predicts temporal sequences. TM exhibits neocortical biological features such as sparse firing and continuous online learning using local Hebbian-learning rules. Methods: We trained a TM model on random sequences of upper-case alphabetical letters, representing sequences of affective states. To model depression, we progressively destroyed synapses in the TM model and examined how that affected the predictive capacity of the network. We found that the number of predictions decreased non-linearly. Results: Destroying 50% of the synapses slightly reduced the number of predictions, followed by a marked drop with further destruction. However, reducing the synapses by 25% distinctly dropped the confidence in the predictions. Therefore, even though the network was making accurate predictions, the network was no longer confident about these predictions. Discussion: These findings explain how interoceptive cortices could be stuck in limited affective states with high prediction error. Connecting ketamine and psilocybin's proposed mechanism of action to depression pathophysiology, the growth of new synapses would allow representing more futuristic predictions with higher confidence. To our knowledge, this is the first study to use the TM model to connect changes happening at synaptic levels to the Bayesian formulation of psychiatric symptomatology. Linking neurobiological abnormalities to symptoms will allow us to understand the mechanisms of treatments and possibly, develop new ones.

18.
Neotrop Entomol ; 52(3): 500-511, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36913124

RESUMEN

Cinnamon (Cinnamomum zeylanicum Blume) essential oil has vast potential as an antimicrobial but is limited by its volatility and rapid degradation. To decrease its volatility and prolong the efficacy of the biocide, cinnamon essential oil was encapsulated into mesoporous silica nanoparticles (MSNs). The characterization of MSNs and cinnamon oil encapsulated with silica nanoparticles (CESNs) was estimated. Additionally, their insecticidal activity against the rice moth Corcyra cephalonica (Stainton) larvae was evaluated. The MSN surface area decreased from 893.6 to 720 m2 g-1 and the pore volume also decreased from 0.824 to 0.7275 cc/g after loading with cinnamon oil. X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), energy-dispersive X-ray spectroscopy (EDX), and N2 sorption by Brunauer-Emmett-Teller (BET) confirmed the successful formation and evolution of the synthesized MSNs and CESN structures. The surface characteristics of MSNs and CESNs were analyzed by scanning and transmission electron microscopy. Compared with the sub-lethal activity values, the order of toxicity after 6 days of exposure was MSNs ˃ CESN ˃ cinnamon oil ˃ silica gel ˃ peppermint oil. The efficacy of CESNs gradually increases its toxicity more than MSN after the 9th day of exposure.


Asunto(s)
Mariposas Nocturnas , Nanopartículas , Aceites Volátiles , Animales , Cinnamomum zeylanicum , Dióxido de Silicio/química , Nanopartículas/química
19.
Artículo en Inglés | MEDLINE | ID: mdl-38939123

RESUMEN

HNN-core is a library for circuit and cellular level interpretation of non-invasive human magneto-/electro-encephalography (MEG/EEG) data. It is based on the Human Neocortical Neurosolver (HNN) software (Neymotin et al., 2020), a modeling tool designed to simulate multiscale neural mechanisms generating current dipoles in a localized patch of neocortex. HNN's foundation is a biophysically detailed neural network representing a canonical neocortical column containing populations of pyramidal and inhibitory neurons together with layer-specific exogenous synaptic drive (Figure 1 left). In addition to simulating network-level interactions, HNN produces the intracellular currents in the long apical dendrites of pyramidal cells across the cortical layers known to be responsible for macroscopic current dipole generation.

20.
Molecules ; 27(21)2022 Oct 24.
Artículo en Inglés | MEDLINE | ID: mdl-36364017

RESUMEN

The current work discusses the production and characterization of new biodegradable nanoparticles for biomedical applications based on insect chitosan. Chitosan has numerous features due to the presence of primary amine groups in repeating units, such as antibacterial and anticancer activities. When polyanion tripolyphosphate is added to chitosan, it creates nanoparticles with higher antibacterial activity than the original chitosan. In this study, the ionic gelation technique was used to make wasp chitosan nanoparticles (WCSNPs) in which TEM and FTIR were used to investigate the physicochemical properties of the nanoparticles. In addition, the antibacterial activities of chitosan nanoparticles against extended-spectrum beta-lactamase (ESBL)- and carbapenemase-producing Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa were evaluated. The extracted wasp chitosan exhibited high solubility in acetic acid and met all standard criteria of all characterization testes for nanoparticles; the zeta potential indicated stable WCSNPs capable of binding to cellular membrane and increasing the cellular uptake. The produced WCSNPs showed growth inhibition activity against all tested strains, and the bacterial count was lower than the initial count. The inhibition percent of WCSNPs showed that the lowest concentration of WCSNPs was found to be effective against tested strains. WCSNPs' antibacterial activity implies that they could be used as novel, highly effective antibacterial agents in a variety of biological applications requiring antibacterial characteristics.


Asunto(s)
Quitosano , Nanopartículas , Avispas , Animales , Quitosano/farmacología , Quitosano/química , Antibacterianos/farmacología , Antibacterianos/química , Pruebas de Sensibilidad Microbiana , Egipto , Nanopartículas/química , Escherichia coli
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