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1.
Nano Lett ; 23(18): 8787-8793, 2023 Sep 27.
Article in English | MEDLINE | ID: mdl-37675974

ABSTRACT

Over the past few years, lithium-ion batteries have been extensively adopted in electric transportation. Meanwhile, the energy density of lithium-ion battery packs has been significantly improved, thanks to the development of materials science and packing technology. Despite recent progress in electric vehicle cruise ranges, the increase in battery charging rates remains a pivotal problem in electrodes with commercial-level mass loadings. Herein, we develop a scalable strategy that incorporates bidirectional freeze-casting into the conventional tape-casting method to fabricate energy-dense, fast-charging battery electrodes with aligned structures. The vertically lamellar architectures in bidirectional freeze-cast electrodes can be roll-to-roll calendered, forming the tilted yet aligned channels. These channels enable directional pathways for efficient lithium-ion transport in electrolyte-filled pores and thus realize fast-charging capabilities. In this work, we not only provide a simple yet controllable approach for building the aligned electrode architectures for fast charging but also highlight the significance of scalability in electrode fabrication considerations.

2.
Proc Natl Acad Sci U S A ; 120(30): e2308009120, 2023 Jul 25.
Article in English | MEDLINE | ID: mdl-37459515

ABSTRACT

As one of the most compact electrochemical energy storage systems, lithium-ion batteries (LIBs) are playing an indispensable role in the process of vehicle electrification to accelerate the shift to sustainable mobility. Making battery electrodes thicker is a promising strategy for improving the energy density of LIBs which is essential for applications with weight or volume constraints, such as electric-powered transportation; however, their power densities are often significantly restricted due to elongated and tortuous charge traveling distances. Here, we propose an effective methodology that couples bidirectional freeze-casting and compression-induced densification to create densified vertically lamellar electrode architectures for compact energy storage. The vertically lamellar architectures not only overcome the critical thickness limit for conventional electrodes but also facilitate and redistribute the lithium-ion flux enabling both high rate capability and stable cyclability. Furthermore, this proposed methodology is universal as demonstrated in various electrochemical active material systems. This study offers a facile approach that realizes simultaneous high energy and high power in high-loading battery electrodes and provides useful rationales in designing electrode architectures for scalable energy storage systems.

3.
J Trop Med ; 2022: 4184326, 2022.
Article in English | MEDLINE | ID: mdl-36249734

ABSTRACT

Leptospirosis is a zoonotic disease caused by the genus Leptospira, presenting complex and dynamic epidemiology. To determine the genetic variability and its phylogenetic relationship of Leptospira spp isolates from three sources in Iquitos (Peruvian Amazon) from 2002 to 2013, seven MLST genes were analyzed to obtain the Sequence Type (ST) and these sequences were concatenated for phylogenetic analysis. The genetic relationship between STs was determined with the goeBURST algorithm and genetic diversity was determined using DnaSP. Of 51 isolates, 48 were pathogenic belonging to five different species: Leptospira interrogans Nascimento 2004, Leptospira santarosai Feil 2004, Leptospira noguchii Haake 2021, Leptospira borgpetersenii Levett 2021, and Leptospira kirschneri Levett 2021. Of 20 STs identified, 60% corresponded to new genotypes circulating only in Peru. The genotypes ST17, ST37, and ST301 were recorded in rodents and humans. A high intraspecific genetic diversity was demonstrated in L. noguchi. The goeBURST analysis revealed three clonal complexes (CCs) and 16 singletons. The STs were found to show high genetic variability and phylogenetic and goeBURST analysis determined that the genotypes found did not form specific groups according to the source of infection or origin, which confirms the zoonotic potential of these STs in an area highly endemic for leptospirosis.

4.
Environ Sci Pollut Res Int ; 28(47): 67032-67052, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34244931

ABSTRACT

A biocomposite system was developed and tested for the removal of the azo dye Reactive Red (RR195) from wastewater. The biocomposite was synthesized using ceramic particles containing 75% alumina which were coated using chitosan cross-linked with oxalic acid. The biocomposite showed high performance at low pH (maximum adsorption capacity = 345.3mg.g-1 at pH=2.0). The physicochemical and structure characteristics of the matrix were evaluated by Z-potential, FTIR-ATR, SEM-EDS, XRD, and porosity. Langmuir sorption isotherm and pseudosecond-order model gave the best fit. The electrostatic interaction between RR195 (due to the sulfonate groups) and the free amino groups of chitosan, enabled successive desorption/regeneration cycles. The maximum removal percentage (>80%) occurred at pH=2.0 due to the cross-linking effect. Experiments at different temperatures allowed the calculation of thermodynamic parameters (ΔG, ΔS, ΔH); adsorption was spontaneous, exothermic, and enthalpy controlled. The presence of inorganic ions ([Formula: see text] ) was analyzed during the adsorption process. This novel biocomposite can be applied as a cost-effective and environmentally friendly adsorbent for anionic azo dye removal from wastewater. The application of chitosan cross-linked with oxalic acid as a coating of the ceramic support enhanced the adsorption capacity and enabled its use under acidic conditions without solubilization.


Subject(s)
Chitosan , Water Pollutants, Chemical , Water Purification , Adsorption , Aluminum Oxide , Azo Compounds , Coloring Agents , Hydrogen-Ion Concentration , Kinetics , Oxalic Acid , Thermodynamics
5.
J Food Sci ; 82(6): 1378-1386, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28471020

ABSTRACT

Thermal inactivation of peroxidase (POD) and lipoxygenase (LOX), both enzymes present in broccoli and Brussels sprouts, is required before freezing, to obtain high-quality precooked frozen vegetables. Rate constants of a 1st-order biphasic model for the heat-labile and heat-resistant POD and LOX isoenzymes were determined at different temperatures (75, 80, and 90 °C) and the corresponding activation energies were estimated using nonlinear regressions. In the case of Brussels sprouts, the activation energies for the resistant and labile fractions were 56.3 and 62.5 kJ/mol for POD and 63.7 and 65.8 kJ/mol for LOX, respectively. For Brussels sprouts, different precooking times were tested to analyze the effect of residual enzyme activity on quality parameters and sensory attributes, after a frozen storage of 4 mo at -20 °C. A significant reactivation of enzyme activity after frozen storage was observed (especially in the case of POD) for short precooking times (<6 min) leading to low-quality parameters at the interior zone of the vegetable. A precooking time of 6 min at 90 °C allowed an adequate inactivation of LOX and POD obtaining a high-quality final frozen vegetable. A sensory analysis confirmed the global acceptability of the product. The obtained results are relevant to define the precooking stage conditions in the production of frozen cruciferous vegetables.


Subject(s)
Brassica/enzymology , Food Handling/methods , Hot Temperature , Lipoxygenase/metabolism , Peroxidase/metabolism , Freezing , Kinetics , Lipoxygenase/chemistry , Peroxidase/chemistry
7.
Pharmacogenet Genomics ; 15(3): 159-65, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15861040

ABSTRACT

Vitamin D has potent anti-tumour properties. Calcitriol [1,25(OH)2D3], the hormonal derivative of vitamin D3, is an antiproliferative and prodifferentiation factor for several cell types, including human squamous cells of the head and neck. Several polymorphisms of the vitamin D receptor (VDR) gene have been described, including a FokI restriction fragment-length polymorphism (RFLP) in exon 2 and an adjacent TaqI RFLP in exon 9. We hypothesized that the VDR FokI and TaqI polymorphisms are associated with the risk of developing squamous cell carcinoma of the head and neck (SCCHN). We conducted a hospital-based, case-control study of 719 SCCHN cases and 821 cancer-free controls (all non-Hispanic Whites) to assess the association between VDR polymorphisms and SCCHN risk. The cases and controls were frequency-matched on age, sex and ethnicity. Polymorphisms at the TaqI and FokI restriction sites were determined from genomic DNA by polymerase chain reaction-RFLP methods. Both homozygous variant genotypes (ff and tt) were associated with a decreased risk of SCCHN [odds ratio (OR)=0.72, 95% confidence interval (CI)=0.53-0.98 and OR=0.64, 95% CI=0.47-0.87, respectively] compared to the common FF and TT genotypes. The VDR variant genotypes were associated with a decreasing risk of SCCHN in a variant allele dose-dependent manner, and the decreasing trend in OR was statistically significant, particularly for the combined genotypes (Ptrend<0.001). These data suggest that the VDR f and t alleles and their genotypes may protect against SCCHN. However, further studies are warranted to confirm these findings.


Subject(s)
Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/prevention & control , Head and Neck Neoplasms/genetics , Head and Neck Neoplasms/prevention & control , Polymorphism, Genetic , Receptors, Calcitriol/genetics , Adult , Age Factors , Aged , Alleles , Calcitriol/metabolism , Case-Control Studies , Cell Differentiation , Dose-Response Relationship, Drug , Exons , Female , Gene Frequency , Genotype , Homozygote , Humans , Male , Middle Aged , Models, Genetic , Odds Ratio , Polymorphism, Restriction Fragment Length , Risk , Sex Factors , Smoking
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