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2.
Bioresour Technol ; 399: 130630, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38522678

RESUMO

The present study aims to enhance the biomethane production potential of microalgae via a dual disintegration process. During this process, the microalgae biomass was firstly subjected to cell wall weakening by thermochemical disintegration (TC) (50 to 80 °C), pH adjustment with alkali, NaOH (6 to 10) and time (0 to 10 min) and, secondly, by bacterial disintegration (BD). TC-BD disintegration was comparatively higher (33 %) than BD (24 %), TC (8.5 %), and control (7 %). A more significant VFA accumulation of 2816 mg/L was recorded for TC-BD. Similarly, a greater substrate anaerobic biodegradability was achieved in TC-BD (0.32 g COD /g COD) than BD (0.21 g COD /g COD), TC alone (0.09 gCOD/g COD) and control (0.08 g COD /g COD), respectively. The TC-BD achieves a positive net profit and an energy ratio of + 0.12 GJ/d and 1.03. The proposed dual disintegration has a promising future for commercialization.


Assuntos
Microalgas , Biomassa , Análise Custo-Benefício , Metano , Bactérias , Anaerobiose
3.
bioRxiv ; 2024 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-38370632

RESUMO

Failure of septation of the interventricular septum (IVS) is the most common congenital heart defect (CHD), but mechanisms for patterning the IVS are largely unknown. We show that a Tbx5+/Mef2cAHF+ progenitor lineage forms a compartment boundary bisecting the IVS. This coordinated population originates at a first- and second heart field interface, subsequently forming a morphogenetic nexus. Ablation of Tbx5+/Mef2cAHF+ progenitors cause IVS disorganization, right ventricular hypoplasia and mixing of IVS lineages. Reduced dosage of the CHD transcription factor TBX5 disrupts boundary position and integrity, resulting in ventricular septation defects (VSDs) and patterning defects, including Slit2 and Ntn1 misexpression. Reducing NTN1 dosage partly rescues cardiac defects in Tbx5 mutant embryos. Loss of Slit2 or Ntn1 causes VSDs and perturbed septal lineage distributions. Thus, we identify essential cues that direct progenitors to pattern a compartment boundary for proper cardiac septation, revealing new mechanisms for cardiac birth defects.

4.
RSC Adv ; 14(9): 6016-6027, 2024 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-38370452

RESUMO

A novel semiorganic nonlinear optical single crystal of rubidium hydrogen succinate hydrate (RbHSH) was grown at room temperature using the slow evaporation solution growth technique (SEST) with water as a solvent for nonlinear optical applications. The grown crystal is a triclinic system with a centrosymmetric space group of P1̄ and the compound is stabilized by intramolecular O-H-O and C-H-O bonding. FTIR spectral studies were used to determine the various functional groups present in the material. The optical transmission spectra of the grown crystal demonstrated that a transparency of 89%, with a low cut off wavelength of 240 nm and an energy band gap of 5.21 eV, which is beneficial to developing advanced photonic and optoelectronic devices in the solar blind UV area. The grown crystal is thermally stable upto 174 °C. The electrical properties of RbHSH crystal exhibit low dielectric loss and a low dielectric constant at high frequencies tends to have good optical characteristics. Mechanical analysis demonstrated that the grown crystal shows the normal indentation size effect (ISE) and falls into the hard material category with n = 1.4. Photoconductivity measurements revealed negative photoconductivity. Photoluminescence studies showed that RbHSH emits blue light with a wavelength of 484 nm. Hirshfeld surface analysis was used to analyze intermolecular interactions in the RbHSH crystal. The grown RbHSH crystal piezoelectric charge coefficient have been calculated (d33 = 13 pC N-1) and it is suitable for piezoelectric device applications. Under continuous-wave laser excitation, the third order nonlinear refractive index (n2), absorption coefficient (ß), and susceptibility (χ(3)) of the RbHSH crystal were found to be 1.6639 × 10-12 (cm2 W-1), 1.1739 × 10-5 (cm W-1) and 4.86331 × 10-9 esu, respectively.

5.
Talanta ; 270: 125542, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38109810

RESUMO

The rational development of efficient nanozymes for the colorimetric detection of targets is still challenging. Herein, Prussian blue analogues of Ni-Co-MoS2 nano boxes were fabricated for colorimetric detection of glyphosate and copper ions owing to its peroxidase like activity. At the sensing system, the Ni-Co-MoS2 nano boxes display high peroxidase activity, which could catalytically oxidize the colourless TMB to blue colour oxTMB. In presence of glyphosate in this sensing system the blue colour is diminished, ascribed to the inhibit the catalytic activity of Ni-Co-MoS2 nano boxes. Concurrently, the addition of copper ion, which result in blue colour was reappear due to the generation of glyphosate-copper complex formation. The Ni-Co-MoS2 nano boxes based colorimetric sensing platform was developed to sensitive detection of glyphosate and copper ions with low detection limit of 3 nM for glyphosate and 3.8 nM for copper. This method also displays satisfactory outcomes from real samples analysis and its good accuracy. Therefore, this work provides a great potential for rapid detection of the targets from the environments.


Assuntos
Glifosato , Peroxidase , Peroxidase/metabolismo , Cobre , Molibdênio , Oxirredução , Peroxidases , Ferrocianetos , Corantes , Colorimetria/métodos , Peróxido de Hidrogênio/análise
6.
Sci Rep ; 13(1): 19219, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-37932312

RESUMO

In this manuscript, a hexagonal-shaped graphene quantum plasmonic nanopatch antenna sensor is designed and investigated on silicon dioxide, zinc oxide and silicon substrates for quantum plasmonic biosensing applications. The optical properties of graphene are demonstrated using Kubo modeling to analyze the plasmon resonance characteristics of the nanopatch antenna. Nano-circuit modeling of the hexagonal-shaped graphene nano-antenna is proposed and validated using CST simulations. The parametric analysis of the hexagonal-shaped nanopatch antenna is performed using design parameters such as R (radius of the hexagon), Tp (thickness of the hexagon) and µc (chemical potential of graphene) to obtain optimum characteristics suitable for quantum plasmonic sensing applications. The study demonstrates that the proposed hexagonal-shaped nano-antenna exhibits gain of 4.9 dBi, 2.46 dBi, 14.99 dBi, 8.25 dBi, 5.15 dBi, 10.87 dBi and 2.4 dBi at 29.87 THz, 30 THz, 35 THz, 113.5 THz, 132.5 THz, 85 THz and 24 THz, respectively. The field enhancement factors observed at these frequencies are 794, 779, 584, 255, 234, 654 and 217, respectively.

7.
Analyst ; 148(19): 4616-4636, 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37712440

RESUMO

Nowadays, the prevalence of metabolic syndromes (MSs) has attracted increasing concerns as it is closely related to overweight and obesity, physical inactivity and overconsumption of energy, making the diagnosis and real-time monitoring of the physiological range essential and necessary for avoiding illness due to defects in the human body such as higher risk of cardiovascular disease, diabetes, stroke and diseases related to artery walls. However, the current sensing techniques are inconvenient and do not continuously monitor the health status of humans. Alternatively, the use of recent wearable device technology is a preferable method for the prevention of these diseases. This can enable the monitoring of the health status of humans in different health domains, including environment and structure. The use wearable devices with the purpose of facilitating rapid treatment and real-time monitoring can decrease the prevalence of MS and long-time monitor the health status of patients. This review highlights the recent advances in wearable sensors toward continuous monitoring of blood pressure and blood glucose, and further details the monitoring of abnormal obesity, triglycerides and HDL. We also discuss the challenges and future prospective of monitoring MS in humans.


Assuntos
Doenças Metabólicas , Humanos , Artérias , Glicemia , Pressão Sanguínea , Obesidade/diagnóstico
8.
Oman J Ophthalmol ; 16(2): 333-335, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37602156

RESUMO

Familial exudative vitreoretinopathy (FEVR) is a rare genetically heterogeneous inherited disorder with varied presentation. We report a case of FEVR with a classic tractional component and a rare co-occurrence of macular hole with subtotal retinal detachment. The diagnosis was made on clinical examination and imaging. There have been four cases of full-thickness macular holes reported in the literature and none with macular hole retinal detachment. The patient underwent vitrectomy for the same and had silicone oil removal with attached retina postoperatively. We want to highlight this rare association and emphasize the importance of regular follow-up of FEVR cases which tend to progress after remaining quiescent for years.

9.
Iran J Vet Res ; 24(1): 58-64, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37378386

RESUMO

Background: Inflammatory bowel disease (IBD) in dogs is often characterized by a relapsing and remitting clinical course. Determination of inflammatory activity is important for assessing the disease extent, severity, and tailoring appropriate treatment. Aims: The study was conducted to record the macroscopic and microscopic changes associated with IBD to assess the usefulness of endoscopy in the diagnosis of the disease and to correlate the clinical activity index (CIBDAI) with endoscopic score. Methods: Thirty-three dogs with idiopathic IBD were selected after thorough examination and exclusion. Gastroduodenoscopy and colonoscopy were performed to document the gross macroscopic intestinal lesions. Histopathology of endoscopic aided biopsy samples was used to confirm the disease. Results: Mucosal erythema and increased friability were the most predominant endoscopic findings in the stomach, duodenum, and colon of IBD dogs. Lymphoplasmacytic infiltration was predominant in the mucosal samples on histopathology and diffuse form of IBD is more common in canines. Gastroduodenoscopy and colonoscopy in combination with endoscopically guided biopsy and histopathology are of value in the assessment and diagnosis of IBD. There was no correlation between the clinical inflammatory bowel disease activity index (CIBDAI) with the endoscopic score. Conclusion: A diffuse form of IBD and colitis is more common in dogs in comparison to human IBD where the disease manifests in two distinct forms. Colonoscopy with ileal biopsy could act as a gold standard in the confirmation of diffuse IBD in dogs. CIBDAI can be used as a reliable measure of clinical signs of inflammation and histopathology can be used as a definitive diagnosis of intestinal inflammation.

10.
Environ Res ; 233: 116415, 2023 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-37343749

RESUMO

The production of reinforced composite materials can generally benefit greatly from the use of natural cellulosic woody fibers as good sustainable resources. Natural plants like hemp, cotton, and bamboo are great options for knitters and crocheters looking to make eco-friendly goods. The current study examines the properties of natural fiber obtained from the stem of the Acacia pennata (AP) plant, as well as its basic physico-chemical, structural, thermal, and mechanical characteristics. The key goal of this work was to investigate how alkali treatment affected the AP fibers' morphology, chemical composition, tensile capabilities, morphological changes, structural changes, and thermal degradation (APFs). The SEM image and pXRD analyses support the improved surface roughness of the fiber, and that was seen after the alkaline treatment. From XRD analysis, the fiber crystallinity index (54.65%) was improved and it was connected to their SEM pictograms in comparison to untreated APF. Alkali-treated AP fibers include a higher percentage of chemical components including cellulose (51.38%) and ash (5.13%). Alkali-treated AP fibers have a lower amount of hemi-cellulose (30.30%), lignin (20.96%), pectin (8.77%), wax (0.12%), and moisture (13.44%) than untreated APF. Their low density and high cellulosic content will improve their ability to fiber matrices. The thermal behavior of AP fiber at various temperatures was demonstrated by TG-DTA analysis, and tensile strength was also investigated.


Assuntos
Acacia , Álcalis/química , Celulose/química , Lignina/química , Resistência à Tração
11.
ACS Omega ; 8(14): 13371-13383, 2023 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-37065084

RESUMO

Metal organic frameworks (MOFs) are topical crystalline materials with high porosity and inner surface areas synthesized from naturally occurring minerals. Such MOFs with transition metals have attracted considerable attention because of their fascinating morphological diversity and tunable characteristics. The coronene-based structural frameworks with transition metal atoms are synthesized by repeating a fixed coronene unit at several levels. In this study, topological indices and NMR and ESR spectral patterns are computed for these MOFs to shed light on their structures and spectral properties. We obtained mathematical expressions of topological indices based on degree and degree-sum values of MOFs for the rectangular, hexagonal, and parallelogram peripheral shapes. Furthermore, the entropy measures of these novel frameworks are evaluated with the help of index functionals and compared to a wide range of degree-based descriptors. The NMR and ESR spectral patterns have been obtained from the distance degree vector sequences and symmetries for the three MOFs.

12.
Polymers (Basel) ; 15(7)2023 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-37050416

RESUMO

Today, new materials based on natural fibres have been emerging day by day to completely eradicate plastics to favour our environmental nature. In this view, the present work is based on the extraction and characterisation of the novel root fibres of the Zea mays (Zm) plant, grown by the hydroponic method. Both the dried untreated and alkali treated root fibres are investigated using a variety of structural, morphological, thermal, elemental and mechanical tests by subjecting both the samples to p-XRD, FT-IR, SEM-EDAX, TGA-DTA, CHNS and tensile strength analyses. Thermal conductivity of the untreated and treated fibres is found using Lee's disc experiment. From p-XRD analysis, the Crystallinity Index, Percentage Crystallinity and Crystallite size of the samples are found. FT-IR studies clarify the different vibrational groups associated with the fibre samples. SEM images show that the surface roughness increases for the chemically treated samples, such that it may be effectively utilised as reinforcement for polymeric composites. The diameter of the fibre samples is found using SEM analysis. According to the EDAX spectrum, Zm fibres in both their raw and processed forms have high levels of Carbon (C) and Oxygen (O). The TGA-DTA tests revealed that the samples of natural fibre have good thermal characteristics. CHNS studies show that Carbon content is high for these samples, which is the characteristic of many natural fibres. Chemical analysis is used to ascertain the prepared samples' chemical makeup. It reveals that both samples have significant amounts of cellulose. The density of the fibres is found to be in the range 0.3-0.6 g/cc, which is much less than any other natural fibre. Therefore, it can be used in light weight applications. From the tensile strength analysis, physical properties such as Young's modulus and micro-fibril angle are determined. The fibres in the roots exhibit a lower tensile strength. Thus, these fibres can be used in powdered form as reinforcement for natural rubber or epoxy composites. After examining all of its properties, it could be reasonably speculated that Zea mays root fibres can be considered as an efficient reinforcement for various matrices to produce attractive bio-composites.

15.
J Mech Behav Biomed Mater ; 140: 105750, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36878080

RESUMO

OBJECTIVE: This study aimed to evaluate the effect of incorporation of strontium based fluoro phosphate glass (SrFPG) 48P2O5-29CaO-14NaO-3CaF2-6SrO on physico chemical and biological properties of mineral trioxide aggregate (MTA). METHODS: Optimized SrFPG glass powder were prepared using planetary ball mill and incorporated into MTA in varying proportion (1, 5, 10 wt%) to obtain SrMT1, SrMT5, SrMT10 bio-composite respectively. The bio-composites were characterized using XRD, FTIR and SEM-EDAX before and after soaking for 28 days in stimulated body fluid (SBF) solution. To assess the mechanical properties and biocompatibility of the prepared bio-composite, density, pH analysis, compressive strength and cytotoxicity evaluation using MTT assay were done before and after soaking for 28 days in SBF solution. RESULTS: A nonlinear variation in compressive strength and pH values was noted. Of the bio-composites, SrMT10 was evidenced with rich apatite formation in XRD, FTIR and SEM with EDAX analysis. MTT assay showed increased cell viability in all the samples before and after in vitro studies.


Assuntos
Vidro , Fosfatos , Vidro/química , Estrôncio/química
17.
Bioresour Technol ; 376: 128857, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36906239

RESUMO

This study aimed to pretreat the waste activated sludge (WAS) by ultrasonication in an energy efficient way by combining sodium citrate with ultrasonic pretreatment at 0.03 g/g suspended solids (SS) of dosage. The ultrasonic pretreatment was done at various (20-200 W) power levels, sludge concentration (7 to 30 g/L), sodium citrate dosages (0.01 to 0.2 g/g SS). An elevated COD solubilization of 26.07 ± 0.6 % was achieved by combined pretreatment at a treatment time of 10 min, ultrasonic power level of 160 W when compared to individual ultrasonic pretreatment (18.6 ± 0.5 %). A higher biomethane yield of 0.26 ± 0.009 L/g COD was achieved in sodium citrate combined ultrasonic pretreatment (SCUP) than ultrasonic pretreatment (UP) 0.145 ± 0.006 L/g COD. Almost 50% of the energy can be saved through SCUP when compared to UP. Future study evaluating SCUP in continuous mode anaerobic digestion is vital.


Assuntos
Biocombustíveis , Esgotos , Citrato de Sódio , Biocombustíveis/análise , Análise Custo-Benefício , Ultrassom , Anaerobiose , Eliminação de Resíduos Líquidos , Metano
19.
Nursing ; 53(2): 61, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36700818
20.
Bioresour Technol ; 369: 128383, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36427767

RESUMO

The main downside of utilizing algal biomass for biofuel production is the rigid cell wall which confines the availability of soluble organics to hydrolytic microbes during biofuel conversion. This constraint reduces the biofuel production efficiency of algal biomass. On the other hand, presenting various pretreatment methods before biofuel production affords cell wall disintegration and enhancement in biofuel generation. The potential of pretreatment methods chiefly relies on the extent of biomass liquefaction, energy, and cost demand. In this review, different pretreatments employed to disintegrate algal biomass were conferred in depth with detailed information on their efficiency in enhancing liquefaction and biofuel yield for pilot-scale implementation. Based on this review, it has been concluded that combinative and phase-separated pretreatments provide virtual input in enhancing the biofuel generation based on liquefaction potential, energy, and cost. Future studies should focus on decrement in cost and energy requirement of pretreatment in depth.


Assuntos
Biocombustíveis , Plantas , Biomassa , Análise Custo-Benefício , Hidrólise
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