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1.
World J Microbiol Biotechnol ; 40(6): 183, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38722449

ABSTRACT

Heterologous production of proteins in Escherichia coli has raised several challenges including soluble production of target proteins, high levels of expression and purification. Fusion tags can serve as the important tools to overcome these challenges. SUMO (small ubiquitin-related modifier) is one of these tags whose fusion to native protein sequence can enhance its solubility and stability. In current research, a simple, efficient and cost-effective method is being discussed for the construction of pET28a-SUMO vector. In order to improve the stability and activity of lysophospholipase from Pyrococcus abyssi (Pa-LPL), a 6xHis-SUMO tag was fused to N-terminal of Pa-LPL by using pET28a-SUMO vector. Recombinant SUMO-fused enzyme (6 H-S-PaLPL) works optimally at 35 °C and pH 6.5 with remarkable thermostability at 35-95 °C. Thermo-inactivation kinetics of 6 H-S-PaLPL were also studied at 35-95 °C with first order rate constant (kIN) of 5.58 × 10- 2 h-1 and half-life of 12 ± 0 h at 95 °C. Km and Vmax for the hydrolysis of 4-nitrophenyl butyrate were calculated to be 2 ± 0.015 mM and 3882 ± 22.368 U/mg, respectively. 2.4-fold increase in Vmax of Pa-LPL was observed after fusion of 6xHis-SUMO tag to its N-terminal. It is the first report on the utilization of SUMO fusion tag to enhance the overall stability and activity of Pa-LPL. Fusion of 6xHis-SUMO tag not only aided in the purification process but also played a crucial role in increasing the thermostability and activity of the enzyme. SUMO-fused enzyme, thus generated, can serve as an important candidate for degumming of vegetable oils at industrial scale.


Subject(s)
Enzyme Stability , Escherichia coli , Pyrococcus abyssi , Recombinant Fusion Proteins , Temperature , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Recombinant Fusion Proteins/chemistry , Escherichia coli/genetics , Escherichia coli/metabolism , Hydrogen-Ion Concentration , Kinetics , Pyrococcus abyssi/genetics , Pyrococcus abyssi/enzymology , Small Ubiquitin-Related Modifier Proteins/metabolism , Small Ubiquitin-Related Modifier Proteins/genetics , Genetic Vectors/metabolism , SUMO-1 Protein/genetics , SUMO-1 Protein/metabolism , SUMO-1 Protein/chemistry , Cloning, Molecular , Solubility
2.
Angew Chem Int Ed Engl ; : e202404264, 2024 May 03.
Article in English | MEDLINE | ID: mdl-38699962

ABSTRACT

Using single-crystal to single-crystal solid/gas reactivity the gold(I) acetylene complex [Au(L1)(η2-HC≡CH)][BArF4] is cleanly synthesized by addition of acetylene gas to single crystals of [Au(L1)(CO)][BArF4] [L1 = tris-2-(4,4'-di-tert-butylbiphenyl)phosphine, ArF = 3,5-(CF3)2C6H3]. This simplest gold-alkyne complex has been characterized by single crystal X-ray diffraction, solution and solid-state NMR spectroscopy and periodic DFT. Bonding of HC≡CH with [Au(L1)]+ comprises both σ-donation and π-backdonation with additional dispersion interactions within the cavity-shaped phosphine.

3.
Heliyon ; 10(9): e30353, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38737253

ABSTRACT

This research paper proposes a novel approach for constructing substitution boxes (S-boxes) over Gaussian integers, which are complex numbers with integer coefficients. The proposed method is based on the properties of the Gaussian integers and their arithmetic operations and ensures the S-boxes exhibit strong cryptographic properties. Furthermore, the paper demonstrates how these S-boxes can be utilized for image encryption through a substitution-permutation network (SPN) over Gaussian integers. The SPN involves iteratively applying the S-box and a permutation layer to the input image, which effectively scrambles the image data. Experimental results show that the proposed method achieves high security and robustness against various attacks while providing efficient encryption and decryption performance. This research thus provides a promising avenue for developing secure image encryption schemes based on Gaussian integers.

4.
Carbohydr Res ; 539: 109122, 2024 May.
Article in English | MEDLINE | ID: mdl-38657354

ABSTRACT

The genomic screening of hyper-thermophilic Pyrococcus abyssi showed uncharacterized novel α-amylase sequences. Homology modelling analysis revealed that the α-amylase from P. abyssi consists of an N-terminal GH57 catalytic domain, α-amylase central, and C-terminal domain. Current studies emphasize in-silico structural and functional analysis, recombinant expression, characterization, structural studies through CD spectroscopy, and ligand binding studies of the novel α-amylase from P. abyssi. The soluble expression of PaAFG was observed in the E. coli Rosetta™ (DE3) pLysS strain upon incubation overnight at 18 °C in an orbital shaker. The optimum temperature and pH of the PaAFG were observed at 90 °C in 50 mM phosphate buffer pH 6. The Km value for PaAFG against wheat starch was determined as 0.20 ± 0.053 mg while the corresponding Vmax value was 25.00 ± 0.67 µmol min-1 mg-1 in the presence of 2 mM CaCl2 and 12.5 % glycerol. The temperature ramping experiments through CD spectroscopy reveal no significant change in the secondary structures and positive and negative ellipticities of the CD spectra showing the proper folding and optimal temperature of PaAFG protein. The RMSD and RMSF of the PaAFG enzyme determined through molecular dynamic simulation show the significant protein's stability and mobility. The soluble production, thermostability and broad substrate specificity make this enzyme a promising choice for various industrial applications.


Subject(s)
Pyrococcus abyssi , Starch , alpha-Amylases , alpha-Amylases/metabolism , alpha-Amylases/chemistry , alpha-Amylases/genetics , Enzyme Stability , Hydrogen-Ion Concentration , Models, Molecular , Pyrococcus abyssi/enzymology , Starch/metabolism , Starch/chemistry , Temperature
5.
Int J Biol Macromol ; 266(Pt 2): 131310, 2024 May.
Article in English | MEDLINE | ID: mdl-38569986

ABSTRACT

Alpha amylase belonging to starch hydrolyzing enzymes has significant contributions to different industrial processes. The enzyme production through recombinant DNA technology faces certain challenges related to their expression, solubility and purification, which can be overcome through fusion tags. This study explored the influence of SUMO, a protein tag reported to enhance the solubility and stability of target proteins when fused to the N-terminal of the catalytic domain of amylase from Pyrococcus abyssi (PaAD). The insoluble expression of PaAD in E. coli was overcome when the enzyme was expressed in a fusion state (S-PaAD) and culture was cultivated at 18 °C. Moreover, the activity of S-PaAD increased by 1.5-fold as compared to that of PaAD. The ligand binding and enzyme activity assays against different substrates demonstrated that it was more active against 1 % glycogen and amylopectin. The analysis of the hydrolysates through HPLC demonstrated that the enzyme activity is mainly amylolytic, producing longer oligosaccharides as the major end product. The secondary structure analyses by temperature ramping in CD spectroscopy and MD simulation demonstrated the enzymes in the free, as well as fusion state, were stable at 90 °C. The soluble production, thermostability and broad substrate specificity make this enzyme a promising choice for various foods, feed, textiles, detergents, pharmaceuticals, and many industrial applications.


Subject(s)
Catalytic Domain , Enzyme Stability , Pyrococcus abyssi , Recombinant Fusion Proteins , Solubility , Recombinant Fusion Proteins/chemistry , Recombinant Fusion Proteins/genetics , Recombinant Fusion Proteins/metabolism , Substrate Specificity , Pyrococcus abyssi/enzymology , Amylases/chemistry , Amylases/metabolism , Amylases/genetics , Hydrolysis , Escherichia coli/genetics , Temperature , Starch/chemistry , Starch/metabolism
6.
Mol Biol Rep ; 51(1): 527, 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38637351

ABSTRACT

BACKGROUND: SnRK2 plays vital role in responding to adverse abiotic stimuli. The applicability of TaSnRK2.4 and TaSnRK2.9 was investigated to leverage the potential of these genes in indigenous wheat breeding programs. METHODS: Genetic diversity was assessed using pre-existing markers for TaSnRK2.4 and TaSnRK2.9. Furthermore, new markers were also developed to enhance their broader applicability. KASP markers were designed for TaSnRK2.4, while CAPS-based markers were tailored for TaSnRK2.9. RESULTS: Analysis revealed lack of polymorphism in TaSnRK2.4 among Pakistani wheat germplasm under study. To validate this finding, available gel-based markers for TaSnRK2.4 were employed, producing consistent results and offering limited potential for application in marker-assisted wheat breeding with Pakistani wheat material. For TaSnRK2.9-5A, CAPS2.9-5A-1 and CAPS2.9-5A-2 markers were designed to target SNP positions at 308 nt and 1700 nt revealing four distinct haplotypes. Association analysis highlighted the significance of Hap-5A-1 of TaSnRK2.9-5A, which exhibited association with an increased number of productive tillers (NPT), grains per spike (GPS), and reduced plant height (PH) under well-watered (WW) conditions. Moreover, it showed positive influence on NPT under WW conditions, GPS under water-limited (WL) conditions, and PH under both WW and WL conditions. High selection intensity observed for Hap-5A-1 underscores the valuable role it has played in Pakistani wheat breeding programs. Gene expression studies of TaSnRK2.9-5A revealed the involvement of this gene in response to PEG, NaCl, low temperature and ABA treatments. CONCLUSION: These findings propose that TaSnRK2.9 can be effectively employed for improving wheat through marker-assisted selection in wheat breeding efforts.


Subject(s)
Drought Resistance , Triticum , Triticum/metabolism , Genotype , Plant Breeding , Bread , Plant Proteins/genetics
7.
Comput Biol Med ; 174: 108146, 2024 May.
Article in English | MEDLINE | ID: mdl-38608320

ABSTRACT

Leukocytes, also called White Blood Cells (WBCs) or leucocytes, are the cells that play a pivotal role in human health and are vital indicators of diseases such as malaria, leukemia, AIDS, and other viral infections. WBCs detection and classification in blood smears offers insights to pathologists, aiding diagnosis across medical conditions. Traditional techniques, including manual counting, detection, classification, and visual inspection of microscopic images by medical professionals, pose challenges due to their labor-intensive nature. However, traditional methods are time consuming and sometimes susceptible to errors. Here, we propose a high-performance convolutional neural network (CNN) coupled with a dual-attention network that efficiently detects and classifies WBCs in microscopic thick smear images. The main aim of this study was to enhance clinical hematology systems and expedite medical diagnostic processes. In the proposed technique, we utilized a deep convolutional generative adversarial network (DCGAN) to overcome the limitations imposed by limited training data and employed a dual attention mechanism to improve accuracy, efficiency, and generalization. The proposed technique achieved overall accuracy rates of 99.83%, 99.35%, and 99.60% for the peripheral blood cell (PBC), leukocyte images for segmentation and classification (LISC), and Raabin-WBC benchmark datasets, respectively. Our proposed approach outperforms state-of-the-art methods in terms of accuracy, highlighting the effectiveness of the strategies employed and their potential to enhance diagnostic capabilities and advance real-world healthcare practices and diagnostic systems.


Subject(s)
Leukocytes , Neural Networks, Computer , Humans , Leukocytes/cytology , Leukocytes/classification , Microscopy/methods , Image Processing, Computer-Assisted/methods , Deep Learning
8.
Small ; : e2310587, 2024 Mar 28.
Article in English | MEDLINE | ID: mdl-38546418

ABSTRACT

The process of N-doping is frequently employed to enhance the properties of carbon quantum dots. However, the precise requirements for nitrogen precursors in producing high-quality N-doped carbon quantum dots (NCQDs) remain undefined. This research systematically examines the influence of various nitrogen dopants on the morphology, optical features, and band structure of NCQDs. The dots are synthesized using an efficient, eco- friendly, and rapid continuous hydrothermal flow technique. This method offers unparalleled control over synthesis and doping, while also eliminating convention-related issues. Citric acid is used as the carbon source, and urea, trizma base, beta-alanine, L-arginine, and EDTA are used as nitrogen sources. Notably, urea and trizma produced NCQDs with excitation-independent fluorescence, high quantum yields (up to 40%), and uniform dots with narrow particle size distributions. Density functional theory (DFT) and time-dependent DFT modelling established that defects and substituents within the graphitic structure have a more significant impact on the NCQDs' electronic structure than nitrogen-containing functional groups. Importantly, for the first time, this work demonstrates that the conventional approach of modelling single-layer structures is insufficient, but two layers suffice for replicating experimental data. This study, therefore, provides essential guidance on the selection of nitrogen precursors for NCQD customization for diverse applications.

9.
Int J Biol Macromol ; 266(Pt 1): 131154, 2024 May.
Article in English | MEDLINE | ID: mdl-38547938

ABSTRACT

Tanneries are one of the most polluted industries known for production of massive amount of solid and liquid wastes without proper management and disposal. In this project we demonstrated the ecofriendly single step dehairing of leather hides with minimum pollution load. In this study, Bacillus species (Bacillus paralicheniformis strain BL.HK, Bacillus cereus strain BS.P) capable of producing proteases was successfully isolated by employing the new optimized selective media named M9-PEA as confirmed by 16sRNA genes sequencing. Sequence of 1493 bp long 16S rRNA genes of Bacillus paralicheniformis strain BL.HK and Bacillus cereus strain BS. P was submitted to GenBank under the accession number OP612692.1, OP612721.1 respectively The Bacillus paralicheniformis strain BL.HK, Bacillus cereus strain BS.P produced extracellur proteases of 28 and 37 KDa as resolved by SDS-PAGE respectively. The enzymes showed temperature optima at 50 °C and 55 °C and pH optima at 8.5, 9.5 respectively. The Proteases of Bacillus paralicheniformis strain BL.HK, Bacillus cereus strain BS.P were employed for dehairing of animal hides. The process resulted in significant removal of interfibriller substances without damage to collagen layer after one hour treatment, which was confirmed by histology, scanning electron microscopy. The quantification of various skin constituents (collagen, uronic acid, hexosamines, and GAGs) and pollution load parameters revealed that enzymatic treatment are more reliable. The results of skin application trials at industrial level with complete elimination of chemicals remark the biotechnological potential of these proteases for ecofriendly dehairing of animal hides without affecting the quality of the leathers produced.


Subject(s)
Bacillus , Peptide Hydrolases , Bacillus/enzymology , Bacillus/genetics , Animals , Peptide Hydrolases/metabolism , Peptide Hydrolases/genetics , Peptide Hydrolases/chemistry , Hydrogen-Ion Concentration , Tanning , Temperature , RNA, Ribosomal, 16S/genetics , Phylogeny
10.
Aust J Rural Health ; 2024 Mar 20.
Article in English | MEDLINE | ID: mdl-38506552

ABSTRACT

INTRODUCTION: Farm workers are at high risk for injuries, and epidemiological data are needed to plan resource allocation. OBJECTIVE: This study identified regions with high farm-related injury rates in the Barwon South West region of Victoria, Australia, for residents aged ≥50 yr. DESIGN: Retrospective synthesis using electronic medical records of emergency presentations occurring during 2017-2019 inclusive for Local Government Areas (LGA) in the study region. For each LGA, age-standardised incidence rates (per 1000 population/year) were calculated. FINDINGS: For men and women combined, there were 31 218 emergency presentations for any injury, and 1150 (3.68%) of these were farm-related. The overall age-standardised rate for farm-related injury presentations was 2.6 (95% CI 2.4-2.7); men had a higher rate than women (4.1, 95% CI 3.9-4.4 versus 1.2, 95% CI 1.0-1.3, respectively). For individual LGAs, the highest rates of farm-related emergency presentations occurred in Moyne and Southern Grampians, both rural LGAs. Approximately two-thirds of farm-related injuries occurred during work activities (65.0%), and most individuals arrived at the hospital by transport classified as "other" (including private car, 83.3%). There were also several common injury causes identified: "other animal related injury" (20.2%), "cutting, piercing object" (19.5%), "fall ⟨1 m" (13.1%), and "struck by or collision with object" (12.5%). Few injuries were caused by machinery (1.7%) and these occurred mainly in the LGA of Moyne (65%). DISCUSSION AND CONCLUSION: This study provides data to inform future research and resource allocation for the prevention of farm-related injuries.

11.
Heliyon ; 10(5): e26529, 2024 Mar 15.
Article in English | MEDLINE | ID: mdl-38444497

ABSTRACT

Reports on development of resilient wheat mutants to aphid infestation-causing heavy losses to wheat production in many parts of the world, are scanty. The present study aimed to identify genetic diversity of wheat mutants in terms of varying degree of resistance to aphid infestation which can help protect wheat crop, improve yields and enhance food security. Resistance response to aphid infestation was studied on newly developed 33 wheat mutants, developed through irradiating seed of an elite wheat cultivar "Punjab-11" with gamma radiations, during three normal growing seasons at two sites. Data on various traits including aphid count per plant, biochemical traits, physiological traits and grain yield was recorded. Meteorological data was also collected to unravel the impact of environmental conditions on aphid infestation on wheat plants. Minimum average aphid infestation was found on Pb-M-2725, Pb-M-2550, and Pb-M-2719 as compared to the wild type. High yielding mutants Pb-M-1323, Pb-M-59, and Pb-M-1272 supported the moderate aphid infestation. The prevailing temperature up to 25 °C showed positive correlation (0.25) with aphid count. Among biochemical traits, POD (0.34), TSP (0.33), TFA (0.324) exhibited a high positive correlation with aphid count. In addition, CAT (0.31), TSS (0.294), and proline content (0.293) also showed a positive correlation with aphid count. However, all physiological traits depicted negative correlation with aphid count, while, a very weak correlation (0.12) was found between mean aphid count and grain yield. In PCA biplots, the biochemical variables clustered together with aphid count, while physiological variables grouped with grain yield. Biochemical parameters contributed most, towards first dimension of the PCA (48.6%) as compared to the physiological variables (13%). The FAMD revealed that mutant lines were major contributor towards total variation; Pb-M-1027, Pb-M-1323, Pb-M-59 were found to be the most diverse lines. The PCA revealed that biochemical parameters played a significant role in explaining variations in aphid resistance, emphasizing their importance in aphid defense mechanisms. The identified mutants can be utilized by the international wheat community for getting insight into the molecular circuits of resistant mechanism against aphids as well as for designing new KASP markers. This study also highlights the importance of considering both genetic and environmental factors in the development of resilient wheat varieties and pave the way for further investigations into the molecular mechanisms underpinning aphid resistance in wheat.

12.
Sci Rep ; 14(1): 5635, 2024 Mar 07.
Article in English | MEDLINE | ID: mdl-38453999

ABSTRACT

Melting of ice in porous media widely exists in energy and environment applications as well as extraterrestrial water resource utilization. In order to characterize the ice-water phase transition within complicated opaque porous media, we employ the nuclear magnetic resonance (NMR) and imaging (MRI) approaches. Transient distributions of transverse relaxation time T2 from NMR enable us to reveal the substantial role of inherent throat and pore confinements in ice melting among porous media. More importantly, the increase in minimum T2 provides new findings on how the confinement between ice crystal and particle surface evolves inside the pore. For porous media with negligible gravity effect, both the changes in NMR-determined melting rate and our theoretical analysis of melting front confirm that conduction is the dominant heat transfer mode. The evolution of mushy melting front and 3D spatial distribution of water content are directly visualized by a stack of temporal cross-section images from MRI, in consistency with the corresponding NMR results. For heterogeneous porous media like lunar regolith simulant, the T2 distribution shows two distinct pore size distributions with different pore-scale melting dynamics, and its maximum T2 keeps increasing till the end of melting process instead of reaching steady in homogeneous porous media.

13.
Placenta ; 148: 31-37, 2024 Mar 25.
Article in English | MEDLINE | ID: mdl-38350223

ABSTRACT

INTRODUCTION: Glucose from placenta is the predominant energy source for the fetus. Individual placentas exhibit a range of glucose handling from apparent net production to high consumption, presumably reflecting an ability of placenta to secure both own and fetal energy needs. A dependency of placenta on glucose as the main energy source could impede fetal supply. Placenta seems to release lactate to maternal side implying loss of energy. Whether placenta takes up ketones is unclear. Our main hypothesis was that the human placenta can release lactate to the maternal side but take up maternal ketones. METHODS: An in vivo study of term uncomplicated pregnancies including 56 women delivered by cesarean section. We measured uterine and umbilical blood flow by Doppler ultrasonography, combined with blood sampling from maternal radial artery, uterine vein, umbilical artery and vein. Lactate and ketones were determined by quantitative nuclear magnetic resonance. RESULTS: Placenta released lactate to the maternal side (median -36.65 µmol/min. Q1, Q3: 78.53, 13.29), p < 0.001), but not to the fetal side. A net uptake of maternal ketones was found (median (Q1, Q3): 59.12 (30.64, 131.46) µmol acetate equivalents/min, p < 0.001) which largely was metabolized by the uteroplacenta. The uptake of ketones was comparable in energy to the loss of lactate. DISCUSSION: Placenta may release lactate to the maternal side. The energy lost by lactate may be compensated by uptake of maternal ketones. This lactate-ketone trade could benefit both placenta and the fetus by providing lactate for maternal gluconeogenesis and ketones for uteroplacental oxidative energy production.


Subject(s)
Lactic Acid , Placenta , Humans , Female , Pregnancy , Placenta/metabolism , Lactic Acid/metabolism , Cesarean Section , Glucose/metabolism , Fetus/metabolism , Energy Metabolism
14.
Article in English | MEDLINE | ID: mdl-38343052

ABSTRACT

Regenerative medicine refers to medical research focusing on repairing, replacing, or regenerating damaged or diseased tissues or organs. Cardiovascular disease (CVDs) is a significant health issue globally and is the leading cause of death in many countries. According to the Centers for Disease Control and Prevention (CDC), one person dies every 34 seconds in the United States from cardiovascular diseases, and according to a World Health Organization (WHO) report, cardiovascular diseases are the leading cause of death globally, taking an estimated 17.9 million lives each year. Many conventional treatments are available using different drugs for cardiovascular diseases, but these treatments are inadequate. Stem cells and nanotechnology are promising research areas for regenerative medicine treating CVDs. Regenerative medicines are a revolutionary strategy for advancing and successfully treating various diseases, intending to control cardiovascular disorders. This review is a comprehensive study of different treatment methods for cardiovascular diseases using different types of biomaterials as regenerative medicines, the importance of different stem cells in therapeutics, the expanded role of nanotechnology in treatment, the administration of several types of stem cells, their tracking, imaging, and the final observation of clinical trials on many different levels as well as it aims to keep readers up to pace on emerging therapeutic applications of some specific organs and disorders that may improve from regenerative medicine shortly.

15.
Int J Biol Macromol ; 259(Pt 2): 129345, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38219941

ABSTRACT

Genome sequence of Pyrococcus abyssi DSM25543 contains a coding sequence (PAB_RS01410) for α/ß hydrolase (WP_010867387.1). Structural analysis revealed the presence of a consensus motif GXSXG and a highly conserved catalytic triad in the amino acid sequence of α/ß hydrolase that were characteristic features of lysophospholipases. A putative lysophospholipase from P. abyssi with its potential applications in oil degumming and starch processing was heterologously produced in E. coli Rosetta (DE3) pLysS in soluble form followed by its purification and characterization. The recombinant enzyme was found to be active at temperature of 40-90 °C and pH 5.5-7.0. However, the enzyme exhibited its optimum activity at 65 °C and pH 6.5. None of the metal ions (Mn2+, Mg2+, Ni2+, Cu2+, Fe2+, Co2+, Zn2+ and Ca2+) being tested had stimulatory effect on lysophospholipase activity. Km and Vmax for hydrolysis of 4-nitrophenyl butyrate were calculated to be 1 ± 0.089 mM and 1637 ± 24.434 U/mg, respectively. It is the first report on the soluble production and characterization of recombinant lysophospholipase from P. abyssi which exhibits its lipolytic activity in the absence of divalent metal ions. Broad substrate specificity, activity and stability at elevated temperatures make recombinant lysophospholipase an ideal candidate for potential industrial applications.


Subject(s)
Lysophospholipase , Pyrococcus abyssi , Pyrococcus abyssi/genetics , Pyrococcus abyssi/metabolism , Lysophospholipase/chemistry , Escherichia coli/genetics , Archaea/metabolism , Metals/pharmacology , Metals/metabolism , Ions/metabolism , Substrate Specificity , Recombinant Proteins/chemistry , Cloning, Molecular
16.
Nat Commun ; 15(1): 874, 2024 Jan 29.
Article in English | MEDLINE | ID: mdl-38286989

ABSTRACT

The urgency of addressing water scarcity and exponential population rise has necessitated the use of sustainable desalination for clean water production, while conventional thermal desalination processes consume fossil fuel with brine rejection. As a promising solution to sustainable solar thermal distillation, we report a scalable mangrove-mimicked device for direct solar vapor generation and passive salt collection without brine discharge. Capillarity-driven salty water supply and continuous vapor generation are ensured by anti-corrosion porous wicking stem and multi-layer leaves, which are made of low-cost superhydrophilic nanostructured titanium meshes. Precipitated salt at the leaf edge forms porous patch during daytime evaporation and get peeled by gravity during night when saline water rewets the leaves, and these salt patches can enhance vaporization by 1.6 times as indicated by our findings. The proposed solar vapor generator achieves a stable photothermal efficiency around 94% under one sun when treating synthetic seawater with a salinity of 3.5 wt.%. Under outdoor conditions, it can produce 2.2 L m-2 of freshwater per day from real seawater, which is sufficient for individual drinking needs. This kind of biomimetic solar distillation devices have demonstrated great capability in clean water production and passive salt collection to tackle global water and environmental challenges.

17.
Heliyon ; 10(1): e23151, 2024 Jan 15.
Article in English | MEDLINE | ID: mdl-38223736

ABSTRACT

Dengue is one of Pakistan's major health concerns. In this study, we aimed to advance our understanding of the levels of knowledge, attitudes, and practices (KAPs) in Pakistan's Dengue Fever (DF) hotspots. Initially, at-risk communities were systematically identified via a well-known spatial modeling technique, named, Kernel Density Estimation, which was later targeted for a household-based cross-sectional survey of KAPs. To collect data on sociodemographic and KAPs, random sampling was utilized (n = 385, 5 % margin of error). Later, the association of different demographics (characteristics), knowledge, and attitude factors-potentially related to poor preventive practices was assessed using bivariate (individual) and multivariable (model) logistic regression analyses. Most respondents (>90 %) identified fever as a sign of DF; headache (73.8 %), joint pain (64.4 %), muscular pain (50.9 %), pain behind the eyes (41.8 %), bleeding (34.3 %), and skin rash (36.1 %) were identified relatively less. Regression results showed significant associations of poor knowledge/attitude with poor preventive practices; dengue vector (odds ratio [OR] = 3.733, 95 % confidence interval [CI ] = 2.377-5.861; P < 0.001), DF symptoms (OR = 3.088, 95 % CI = 1.949-4.894; P < 0.001), dengue transmission (OR = 1.933, 95 % CI = 1.265-2.956; P = 0.002), and attitude (OR = 3.813, 95 % CI = 1.548-9.395; P = 0.004). Moreover, education level was stronger in bivariate analysis and the strongest independent factor of poor preventive practices in multivariable analysis (illiterate: adjusted OR = 6.833, 95 % CI = 2.979-15.672; P < 0.001) and primary education (adjusted OR = 4.046, 95 % CI = 1.997-8.199; P < 0.001). This situation highlights knowledge gaps within urban communities, particularly in understanding dengue transmission and signs/symptoms. The level of education in urban communities also plays a substantial role in dengue control, as observed in this study, where poor preventive practices were more prevalent among illiterate and less educated respondents.

18.
ChemSusChem ; 17(7): e202301351, 2024 Apr 08.
Article in English | MEDLINE | ID: mdl-38009824

ABSTRACT

We have used density functional theory simulations to explore the topological characteristics of a new MXene-like material, V4C3, and its oxide counterpart, assessing their potential as anode materials for Mg-ion batteries. Our research reveals that V4C3 monolayer is a topological type-II nodal line semimetal, protected by time reversal and spatial inversion symmetries. This type-II nodal line is marked by unique drumhead-like edge states that appear either inside or outside the loop circle, contingent upon the edge ending. Intriguingly, even with an increase in metallicity due to oxygen functionalization, the topological features of V4C3 remain intact. Consequently, the monolayer V4C3 has a topologically enhanced electrical conductivity that amplifies further upon oxygen functionalization. During the charging phase, a remarkable storage concentration led to a peak specific capacity of 894.73 mAh g-1 for V4C3, which only decreases to 789.33 mAh g-1 for V4C3O2. When compared to V2C, V4C3 displays a significantly lower specific capacity loss due to functionalization, demonstrating its superior electrochemical properties. Additionally, V4C3 and V4C3O2 exhibit moderate average open-circuit voltages (0.54 V for V4C3 and 0.58 V for V4C3O2) and energy barriers for intercalation migration (ranging between 0.29-0.63 eV), which are desirable for anode materials. Thus, our simulation results support V4C3 potential as an efficient anode material for Mg-ion batteries.

19.
Chem Rec ; 24(1): e202300302, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38010947

ABSTRACT

As supercapacitor (SC) technology continues to evolve, there is a growing need for electrode materials with high energy/power densities and cycling stability. However, research and development of electrode materials with such characteristics is essential for commercialization the SC. To meet this demand, the development of superior electrode materials has become an increasingly critical step. The electrochemical performance of SCs is greatly influenced by various factors such as the reaction mechanism, crystal structure, and kinetics of electron/ion transfer in the electrodes, which have been challenging to address using previously investigated electrode materials like carbon and metal oxides/sulfides. Recently, tellurium and telluride-based materials have garnered increasing interest in energy storage technology owing to their high electronic conductivity, favorable crystal structure, and excellent volumetric capacity. This review provides a comprehensive understanding of the fundamental properties and energy storage performance of tellurium- and Te-based materials by introducing their physicochemical properties. First, we elaborate on the significance of tellurides. Next, the charge storage mechanism of functional telluride materials and important synthesis strategies are summarized. Then, research advancements in metal and carbon-based telluride materials, as well as the effectiveness of tellurides for SCs, were analyzed by emphasizing their essential properties and extensive advantages. Finally, the remaining challenges and prospects for improving the telluride-based supercapacitive performance are outlined.

20.
Int J Biol Macromol ; 256(Pt 1): 128387, 2024 Jan.
Article in English | MEDLINE | ID: mdl-38000593

ABSTRACT

Alpha amylases catalyse the hydrolysis of α-1, 4-glycosidic bonds in starch, yielding glucose, maltose, dextrin, and short oligosaccharides, vital to various industrial processes. Structural and functional insights on α-amylase from Methanocaldococcus jannaschii were computationally explored to evaluate a catalytic domain and its fusion with a small ubiquitin-like modifier (SUMO). The recombinant proteins' production, characterization, ligand binding studies, and structural analysis of the cloned amylase native full gene (MjAFG), catalytic domain (MjAD) and fusion enzymes (S-MjAD) were thoroughly analysed in this comparative study. The MjAD and S-MjAD showed 2-fold and 2.5-fold higher specific activities (µmol min-1 mg -1) than MjAFG at 95 °C at pH 6.0. Molecular modelling and MD simulation results showed that the removal of the extra loop (178 residues) at the C-terminal of the catalytic domain exposed the binding and catalytic residues near its active site, which was buried in the MjAFG enzyme. The temperature ramping and secondary structure analysis of MjAFG, MjAD and S-MjAD through CD spectrometry showed no notable alterations in the secondary structures but verified the correct folding of MjA variants. The chimeric fusion of amylases with thermostable α-glucosidases makes it a potential candidate for the starch degrading processes.


Subject(s)
Methanocaldococcus , alpha-Amylases , alpha-Amylases/chemistry , Methanocaldococcus/metabolism , Archaea/metabolism , Amylases/chemistry , Starch/metabolism
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