Tag: pubmed

Biomed Phys Eng Express. 2021 Nov 9. doi: 10.1088/2057-1976/ac37cb. Online ahead of print.

ABSTRACT

The dose rate distributions delivered to 55 prostate and head & neck (H&N) cancer patients treated with a helical TomoTherapy (HT) system were resolved and assessed with regard to pitch and field width defined during treatment planning. Statistical analysis of the studied cases showed that the median treatment delivery time was 4.4 min and 6.3 min for the prostate and H&N cases, respectively. Dose rate volume histogram data for the studied cases showed that the 25% and 12% of the volume of the planning target volumes of the prostate and H&N cases are irradiated with a dose rate of greater or equal to 1 Gy/min. Quartile dose rate (QDR) data confirmed that in HT, where the target is irradiated in slices, most of the dose is delivered to each voxel of the target when it travels within the beam. Analysis of the planning data from all cases showed that this lasts for 68 s (median value). QDRs results showed that using the 2.5 cm field width, 75% of the prescribed dose is delivered to target voxels with a median dose rate of at least 3.2 Gy/min and 4.5 Gy/min, for the prostate and H&N cases, respectively. Systematically higher dose rates were observed for the H&N cases due to the shallower depths of the lesions in this anatomical site. Delivered dose rates were also found to increase with field width and pitch setting, due to the higher output of the system which, in general, results in accordingly decreased total treatment time. The biological effect of the dose rate findings of this work needs to be further investigated using in-vitro studies and clinical treatment data.

PMID:34755680 | DOI:10.1088/2057-1976/ac37cb

Bioresour Technol. 2021 Oct 29;344(Pt B):126181. doi: 10.1016/j.biortech.2021.126181. Online ahead of print.

ABSTRACT

This article presents a methodology for determining the kinetic parameters of biomass based on thermogravimetric analysis and the Coats-Redfern procedure with 27 model equations. Maize samples stored for approximately one year were used herein. The first sub-stage of pyrolysis was a first-order reaction with nuclei growth of n = 1, and the second sub-stage indicated a different kinetic order (1.5) of the reaction. The last sub-step showed good convergence with the first-order reaction and nuclei growth of n = 1.5. The activation energy reached up to 71.6 kJ/mol for tżhe selected parts of the stalk fraction, whereas it decreased to 6.5 kJ/mol for the others. A simplified method for approximating the composition of the biomass is also presented. In the composition of stalks, the fraction of hemicellulose was the highest, followed by that of cellulose, whereas in the composition of leaves and whole plant samples, an opposite trend was observed.

PMID:34755652 | DOI:10.1016/j.biortech.2021.126181

Sci Rep. 2021 Nov 9;11(1):22000. doi: 10.1038/s41598-021-01057-0.

ABSTRACT

The electrocaloric (EC) effect is the change in temperature and entropy of a material driven by the application of an electric field. Our tight-binding calculations linked to Fermi statistics, show that the EC effect can be produced in trilayer graphene (TLG) structures connected to a heat source, triggered by changes in the electronic density of states (DOS) at the Fermi level when external gate fields are applied on the outer graphene layers. We demonstrate that entropy changes are sensitive to the stacking arrangement in TLG systems. The AAA-stacked TLG presents an inverse EC response (cooling) regardless of the temperature value and gate field potential strength, whereas the EC effect in ABC-stacked TLG remains direct (heating) above room temperature. We reveal otherwise the TLG with Bernal-ABA stacking generates both the direct and inverse EC response within the same sample, associated with gate-dependent electronic transitions of thermally excited charge carriers from the valence band to the conduction band in the band structure. The novel charge carrier electrocaloric effect we propose in quantum layered systems may bring a wide variety of prototype van der Waals materials that could be used as versatile platforms to controlling the thermal response in nanodevices.

PMID:34753972 | DOI:10.1038/s41598-021-01057-0

Sci Rep. 2021 Nov 9;11(1):21976. doi: 10.1038/s41598-021-01032-9.

ABSTRACT

Textile-reinforced concrete has emerged in recent years as a new and valuable construction material. The design of textile-reinforced concrete requires knowledge on the mechanical properties of different textile types as well as their reinforcing behaviour under different loading conditions. Conventional load-bearing tests tend to be complex, time-consuming, costly and can even lack consistent specifications. To mitigate such drawbacks, a standardised tensile test for fibre strands was used to characterise the material properties needed for the design of a textile-reinforced concrete member. The standardised tensile test uses a fibre strand with 160 mm length, which is cut out of a textile grid. For the sake of this study, an epoxy resin-soaked AR-glass reinforcement was considered. The results show that the textile reinforcement has a linear-elastic behaviour, and the ultimate tensile strength can be statistically modelled by a Gumbel distribution. Furthermore, the results indicate that the modulus of elasticity is not influenced by the length or the number of fibre strands. Therefore, the mean value attained from the standardised test can be used for design purposes. These findings are essential to derive an appropriate partial safety factor for the calculation of the design values of the tensile strength and can be used to determine the failure probability of textile-reinforced concrete members.

PMID:34753961 | DOI:10.1038/s41598-021-01032-9

Sci Rep. 2021 Nov 9;11(1):21925. doi: 10.1038/s41598-021-01155-z.

ABSTRACT

Cord blood transplantation (CBT) provides a treatment scheme for hematologic diseases and leukemia in both children and adults. However, adverse reactions and transplantation-related death may still occur in patients receiving CBT even when donor and recipient have fully matched HLA in high-resolution HLA typing analysis. Single nucleotide polymorphisms (SNPs) of HLA-related and unrelated genes are known to associate with disease status of patients with unrelated stem cell transplantation. In this study, the genomic regions ranging from 500 base pairs upstream to 500 base pairs downstream of the eight SNPs that were reported as transplantation determinants by Petersdorf et al. were analyzed to evaluate whether genetic variants were associated with the survival status of patients, and the risk for severe (grades 3-4) graft-versus-host disease (GVHD) or cytomegalovirus (CMV) infection/reactivation. The analyses were performed in the mode of recipient genotype, donor genotype, and recipient-donor mismatching, respectively. By analysis of sixty-five patients and their HLA-matched unrelated donors, we found that five SNPs were associated with patient survival which included the recipient genotype with SNPs of rs107822 in the RING1 gene, and rs2070120, rs17220087 and rs17213693 in the HLA-DOB gene; and the recipient-donor mismatching with SNPs of rs9282369 in HLA-DOA gene, and rs2070120, rs17220087 and rs17213693 in the HLA-DOB gene. Five SNPs were associated with the risk for severe GVHD which included the donor genotype with SNPs of rs213210 and rs2523675; the recipient genotype with SNPs of rs9281491 in the HCP5 gene; and the recipient-donor mismatching with SNPs of rs209130 in the TRIM27 gene, and rs986522 in the COL11A2 gene. Six SNPs were related to the risk for CMV infection/reactivation which included the donor genotype with SNPs of rs435766, rs380924, and rs2523957; and the recipient-donor mismatching with SNPs of rs2070120, rs17220087, and rs17213693 in the HLA-DOB gene; and rs435766 and rs380924 in the MICD gene. This study provides the basis for larger analyses and if the results are confirmed, a way of selecting better unrelated CBT candidate donors.

PMID:34753965 | DOI:10.1038/s41598-021-01155-z

Nat Commun. 2021 Nov 9;12(1):6477. doi: 10.1038/s41467-021-26873-w.

ABSTRACT

Two-dimensional electron systems in a quantizing magnetic field are regarded as of exceptional interest, considering the possible role of anyons-quasiparticles with non-boson and non-fermion statistics-in applied physics. To this day, essentially none but the fractional states of the quantum Hall effect (FQHE) have been experimentally realized as a system with anyonic statistics. In determining the thermodynamic properties of anyon matter, it is crucial to gain insight into the physics of its neutral excitations. We form a macroscopic quasi-equilibrium ensemble of neutral excitations – spin one anyon complexes in the Laughlin state ν = 1/3, experimentally, where ν is the electron filling factor. The ensemble is found to have such a long lifetime that it can be considered the new state of anyon matter. The properties of this state are investigated by optical techniques to reveal its Bose properties.

PMID:34753935 | DOI:10.1038/s41467-021-26873-w

Nat Commun. 2021 Nov 9;12(1):6454. doi: 10.1038/s41467-021-26792-w.

ABSTRACT

Over the next decade, more than a million eukaryotic species are expected to be fully sequenced. This has the potential to improve our understanding of genotype and phenotype crosstalk, gene function and interactions, and answer evolutionary questions. Here, we develop a machine-learning approach for utilizing phylogenetic profiles across 1154 eukaryotic species. This method integrates co-evolution across eukaryotic clades to predict functional interactions between human genes and the context for these interactions. We benchmark our approach showing a 14% performance increase (auROC) compared to previous methods. Using this approach, we predict functional annotations for less studied genes. We focus on DNA repair and verify that 9 of the top 50 predicted genes have been identified elsewhere, with others previously prioritized by high-throughput screens. Overall, our approach enables better annotation of function and functional interactions and facilitates the understanding of evolutionary processes underlying co-evolution. The manuscript is accompanied by a webserver available at: https://mlpp.cs.huji.ac.il .

PMID:34753957 | DOI:10.1038/s41467-021-26792-w

Transl Psychiatry. 2021 Nov 9;11(1):575. doi: 10.1038/s41398-021-01708-w.

ABSTRACT

Convergent research identifies a general factor (“P factor”) that confers transdiagnostic risk for psychopathology. Large-scale networks are key organizational units of the human brain. However, studies of altered network connectivity patterns associated with the P factor are limited, especially in early adolescence when most mental disorders are first emerging. We studied 11,875 9- and 10-year olds from the Adolescent Brain and Cognitive Development (ABCD) study, of whom 6593 had high-quality resting-state scans. Network contingency analysis was used to identify altered interconnections associated with the P factor among 16 large-scale networks. These connectivity changes were then further characterized with quadrant analysis that quantified the directionality of P factor effects in relation to neurotypical patterns of positive versus negative connectivity across connections. The results showed that the P factor was associated with altered connectivity across 28 network cells (i.e., sets of connections linking pairs of networks); p_PERMUTATION values < 0.05 FDR-corrected for multiple comparisons. Higher P factor scores were associated with hypoconnectivity within default network and hyperconnectivity between default network and multiple control networks. Among connections within these 28 significant cells, the P factor was predominantly associated with “attenuating” effects (67%; p_PERMUTATION < 0.0002), i.e., reduced connectivity at neurotypically positive connections and increased connectivity at neurotypically negative connections. These results demonstrate that the general factor of psychopathology produces attenuating changes across multiple networks including default network, involved in spontaneous responses, and control networks involved in cognitive control. Moreover, they clarify mechanisms of transdiagnostic risk for psychopathology and invite further research into developmental causes of distributed attenuated connectivity.

PMID:34753911 | DOI:10.1038/s41398-021-01708-w

Nat Commun. 2021 Nov 9;12(1):6453. doi: 10.1038/s41467-021-26716-8.

ABSTRACT

Anisotropic triangular antiferromagnets can host two primary spin excitations, namely, spinons and triplons. Here, we utilize polarization-resolved Raman spectroscopy to assess the statistics and dynamics of spinons in Ca₃ReO₅Cl₂. We observe a magnetic Raman continuum consisting of one- and two-pair spinon-antispinon excitations as well as triplon excitations. The twofold rotational symmetry of the spinon and triplon excitations are distinct from magnons. The strong thermal evolution of spinon scattering is compatible with the bosonic spinon scenario. The quasilinear spinon hardening with decreasing temperature is envisaged as the ordering of one-dimensional topological defects. This discovery will enable a fundamental understanding of novel phenomena induced by lowering spatial dimensionality in quantum spin systems.

PMID:34753923 | DOI:10.1038/s41467-021-26716-8

Med Sci Monit. 2021 Nov 10;27:e933424. doi: 10.12659/MSM.933424.

ABSTRACT

BACKGROUND Female-pattern hair loss (FPHL) is a common disorder affecting women, and FPHL can cause psychological dysfunction and affect the social activities of patients. The disease-causing mechanisms are believed to be similar to those of male androgenetic alopecia (MAGA). Although genome-wide association studies (GWAS) have confirmed susceptibility genes/loci for MAGA, the associations between these genetic loci and FPHL are largely unknown. We investigated the associations between susceptibility loci for MAGA and FPHL in a Chinese Han population; a literature review of susceptibility loci associated with MAGA for FPHL was also performed. MATERIAL AND METHODS Twenty-two previously reported sites were analyzed with the Sequenom iPlex platform, and the genotype statistical analysis consisted of a trend test and conservative accounting. The samples comprised 82 patients diagnosed with FPHL by dermatoscopy and 381 healthy controls from the Chinese Han population. RESULTS No significantly associated variants were found in this FPHL study. The examined 22 tag SNPs in MAGA may not be associated with FPHL. The results of the current study in a Chinese Han population support the previous negative association obtained for a European population. CONCLUSIONS This was the first study exploring whether identified MAGA-associated loci confer susceptibility to FPHL in a Chinese Han population, and dermatoscopy was used to improve the diagnostic accuracy. However, there was no evidence of a relationship between susceptibility genes for MAGA and FPHL, and the results indicated that FPHL and MAGA are etiologically separate entities. Therefore, a systematic GWAS approach to FPHL may be required to clarify associated pathophysiological uncertainties.

PMID:34753897 | DOI:10.12659/MSM.933424