Spatially Resolved Operando Synchrotron-Based X-Ray Diffraction Measurements of Ni-Rich Cathodes for Li-Ion Batteries

Understanding the performance of commercially relevant cathode materials for lithium-ion (Li-ion) batteries is vital to realize the potential of high-capacity materials for automotive applications. Of particular interest is the spatial variation of crystallographic behavior across (what can be) highly inhomogeneous electrodes. In this work, a high-resolution X-ray diffraction technique was used to obtain operando transmission measurements of Li-ion pouch cells to measure the spatial variances in the cell during electrochemical cycling. Through spatially resolved investigations of the crystallographic structures, the distribution of states of charge has been elucidated. A larger portion of the charging is accounted for by the central parts, with the edges and corners delithiating to a lesser extent for a given average electrode voltage. The cells were cycled to different upper cutoff voltages (4.2 and 4.3 V vs. graphite) and C-rates (0.5, 1, and 3C) to study the effect on the structure of the NMC811 cathode. By combining this rapid data collection method with a detailed Rietveld refinement of degraded NMC811, the spatial dependence of the degradation caused by long-term cycling (900 cycles) has also been shown. The variance shown in the pristine measurements is exaggerated in the aged cells with the edges and corners offering an even lower percentage of the charge. Measurements collected at the very edge of the cell have also highlighted the importance of electrode alignment, with a misalignment of less than 0.5 mm leading to significantly reduced electrochemical activity in that area.</jats:p

Residues of chlorinated pesticides in mother\u27s milk and child\u27s serum

Uzorci mlijeka i seruma 27 hospitaliziranih dojilja iz Bjelovara i Zaboka s okolnim mjestima analizirani su na ostatke kloriranih insekticida aldrina, dieldrina, endrina, heptaklora, heptaklor epoksida, lindana i ostalih stereoizomera heksaklorcikloheksana, pp-\u27DDT-a i metabolita (pp-\u27DDE i pp-\u27DDD) i op-\u27DDT. Posebno je još analizirano 18 seruma majki i isto toliko seruma njihove djece koji su svi iz Zagreba. U uzorcima smo dokazali prisutnost samo Gama-HCH (Lindan). Alfa-HCH, pp-\u27DDE, op-\u27DDT, pp-\u27DDD i pp-\u27DDT. Koncentracije nađenih insekticida mnogo su veće u mlijeku dojilja nego u serumima. U serumima djece bilo je manje samo pp-\u27DDE i pp-\u27DDT nego u serumima njihovih majki. Uzorci seruma dojilja iz Zaboka i okolnih mjesta, hospitaliziranih u Zaboku i serumi dojilja iz Bjelovara hospitaliziranih u Zagrebu (N = 27) sadržavaju više navedenih insekticida nego uzorci seruma dojilja s područja Zagreba (N = 18).Milk samples obtained from 27 hospitalized lactating women and an equal number of sera from the same women were examined for residues of chlorinated hydrocarbon insecticides: aldrin, dieldrin, endrin, heptachlor, heptachlorepoxide, lindan and other steroisomers of hexachlorcyclohexane, pp\u27DDT and its metabolites (pp\u27-DDE, pp\u27-DDD) and op\u27-DDT. Additional 18 samples of mother\u27s sera and an equal number of their children\u27s sera were examined separately. The aim was to find out whether there is a correlation between the pesticide residues in mother\u27s serum and mother\u27s milk and in the serum of the mother and her child. The insecticides were determined according to the procedure used by the US Food and Drug Administration (4). Chlorinated hydrocarbon insecticides in the serum were examined with the method described by Wyllie and coworkers (5). In all samples only the presence of a-HCH, y-HCH, pp\u27-DDE, op\u27-DDT, pp\u27-DDD and pp\u27-DDT could be demonstrated. The concentration ratio between mother\u27s milk and serum was between 4 and 11. The concentration ratio between mother\u27s and child\u27s serum was below 1 except for pp\u27-DDE and pp\u27-DDT

Finishing the euchromatic sequence of the human genome

The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead

Using In-Situ Laboratory and Synchrotron-Based X-ray Diffraction for Lithium-Ion Batteries Characterization: A Review on Recent Developments

Renewable technologies, and in particular the electric vehicle revolution, have generated tremendous pressure for the improvement of lithium ion battery performance. To meet the increasingly high market demand, challenges include improving the energy density, extending cycle life and enhancing safety. In order to address these issues, a deep understanding of both the physical and chemical changes of battery materials under working conditions is crucial for linking degradation processes to their origins in material properties and their electrochemical signatures. In situ and operando synchrotron-based X-ray techniques provide powerful tools for battery materials research, allowing a deep understanding of structural evolution, redox processes and transport properties during cycling. In this review, in situ synchrotron-based X-ray diffraction methods are discussed in detail with an emphasis on recent advancements in improving the spatial and temporal resolution. The experimental approaches reviewed here include cell designs and materials, as well as beamline experimental setup details. Finally, future challenges and opportunities for battery technologies are discussed

Quantitative polymerase chain reaction for diagnosis of soil-transmitted helminth infections: a comparison with a flotation-based technique and an investigation of variability in DNA detection

Appropriate diagnostic techniques are crucial to global soil-transmitted helminth (STH) control efforts. The recommended Kato-Katz method has low sensitivity in low-transmission settings. Quantitative polymerase chain reaction (qPCR) is a highly sensitive alternative diagnostic option. However, little is known about the variability in qPCR results, and there are few published comparisons between qPCR and other microscopy-based techniques such as sodium nitrate flotation (SNF). Using 865 stool samples collected from 571 individuals, we compared SNF and qPCR in terms of diagnostic sensitivity and infection intensity measurements. In addition, we conducted repeated examinations on a single Necator americanus-positive stool sample over a 6-month period. Results showed good diagnostic agreement between SNF and qPCR for Ascaris spp. (κ = 0.69, P < 0.001), and moderate agreement for hookworm (κ = 0.55, P < 0.001) and Trichuris spp. (κ = 0.50, P < 0.001). Quantitative polymerase chain reaction demonstrated higher sensitivity than SNF for Ascaris spp. (94.1% versus 68.1%) and hookworm (75.7% versus 66.9%) but not for Trichuris spp. (53.1% versus 81.3%), which had very low prevalence. Sodium nitrate flotation and qPCR infection intensity measurements were strongly correlated for Ascaris spp. (ρ = 0.82, P < 0.001) and moderately correlated for hookworm (ρ = 0.58, P < 0.001). Repeated examinations using qPCR showed that N. americanus cycle threshold values decreased significantly at 1 month and remained stable thereafter. Results confirm the high diagnostic sensitivity of qPCR for Ascaris spp. and hookworm, particularly for light-intensity infections, which is ideal for settings approaching transmission elimination. Results support the potential for qPCR to be used as a quantitative assay for STH. Further research is needed in settings where Trichuris trichiura is endemic

Genetic and environmental influences on height from infancy to early adulthood: An individual-based pooled analysis of 45 twin cohorts

Height variation is known to be determined by both genetic and environmental factors, but a systematic description of how their influences differ by sex, age and global regions is lacking. We conducted an individual-based pooled analysis of 45 twin cohorts from 20 countries, including 180,520 paired measurements at ages 1–19 years. The proportion of height variation explained by shared environmental factors was greatest in early childhood, but these effects remained present until early adulthood. Accordingly, the relative genetic contribution increased with age and was greatest in adolescence (up to 0.83 in boys and 0.76 in girls). Comparing geographic-cultural regions (Europe, North-America and Australia, and East-Asia), genetic variance was greatest in North-America and Australia and lowest in East-Asia, but the relative proportion of genetic variation was roughly similar across these regions. Our findings provide further insights into height variation during childhood and adolescence in populations representing different ethnicities and exposed to different environments