Search

Abstract We present a detailed study concerning a new physics scenario involving four fermion operators of the Nambu-Jona-Lasinio type characterized by a strong-coupling ultraviolet fixed point where composite particles are formed as bound states of elementary fermions at the scale Λ = O TeV $$ \Lambda =\mathcal{O}\left(\textrm{TeV}\right) $$ . After implementing the model in the Universal FeynRules Output format, we focus on the phenomenology of the scalar leptoquarks at the LHC and the High-Luminosity option. Leptoquark particles have undergone extensive scrutiny in the literature and experimental searches, primarily relying on pair production and, more recently, incorporating single, Drell-Yan t-channel, and lepton-induced processes. This study marks, for the first time, the examination of these production modes at varying jet multiplicities. Novel mechanisms emerge, enhancing the total production cross section. A global strategy is devised to capture all final state particles produced in association with leptoquarks or originating from their decay, which we termed “exclusive”, in an analogy to the nomenclature used in nuclear reactions. The assessment of the significance in current and future LHC runs, focusing on the case of a leptoquark coupling to a muon–c quark pair, reveals greater sensitivity compared to ongoing searches. Given this heightened discovery potential, we advocate the incorporation of exclusive leptoquark searches in future investigations at the LHC.

Background: Fumonisins (FUMs) are among the most common mycotoxins in plant-derived food products. FUMs contamination has considerably impacted human and animal health, while causing significant economic losses. Hence, management of FUMs contamination in food production and supply chains is needed. The toxicities of FUMs have been widely investigated. FUMs management has been reported and several available strategies have been developed successfully to mitigate FUMs contamination present in foods. However, currently available management of FUMs contamination from different phases of food chains and the mechanisms of some major strategies are not comprehensively summarized. Aim of review: This review comprehensively characterize the occurrence, impacts, and management of FUMs contamination across food production and supply chains. Pre- and post-harvest strategies to prevent FUMs contamination also are reviewed, with an emphasis on the potential applications and the mechanisms of major mitigation strategies. The presence of modified FUMs products and their potential toxic effects are also considered. Importantly, the potential application of biotechnological approaches and emerging technologies are enunciated. Key scientific concepts of review: Currently available pre- and post-harvest management of FUMs contamination primarily involves prevention and decontamination. Prevention strategies are mainly based on limiting fungal growth and FUMs biosynthesis. Decontamination strategies are implemented through alkalization, hydrolysis, thermal or chemical transformation, and enzymatic or chemical degradation of FUMs. Concerns have been raised about toxicities of modified FUMs derivatives, which presents challenges for reducing FUMs contamination in foods with conventional methodologies. Integrated prevention and decontamination protocols are recommended to control FUMs contamination across entire value chains in developed countries. In developing countries, several other approaches, including cultivating, introducing Bt maize, simple sorting/cleaning, and dehulling, are suggested. Future studies should focus on biotechnological approaches, emerging technologies, and metagenomic/genomic identification of new degradation enzymes that could allow better opportunities to manage FUMs contamination in the entire food system.

Abstract We study the contribution of a heavy right-handed Majorana neutrino to neutrinoless double beta decay (0νββ) via four-fermion effective interactions of Nambu-Jona-Lasinio (NJL) type. In this physical scenario, the sterile neutrino contributes to the nuclear transition through gauge, contact, and mixed interactions. Using the lower limit on the half-life of 0νββ from the KamLAND-Zen experiment, we then constrain the effective right-handed coupling between the sterile neutrino and the W boson: G R W $$ {\mathcal{G}}_R^W $$ . Eventually, we show that the obtained bounds are compatible with those found in the literature, which highlights the complementarity of this type of phenomenological study with high-energy experiments.

MicroRNAs (miRNAs) are a large class of non-coding RNAs that play important roles in the proliferation and differentiation of adipocytes. Our previous sequencing analysis revealed higher expression of miR-369-3p in the longissimus muscle of 2-month-old Aohan fine-wool sheep (AFWS) compared to 12-month-old sheep (P), suggesting that miR-369-3p may regulate fat deposition in AFWS. To test this, miR-369-3p mimics, inhibitors, and negative controls (NCs) were constructed and transfected into AFWS preadipocytes. After transfection with miR-369-3p mimics, we found a decrease (P) in the expression of genes and proteins related to cell proliferation and differentiation, detected by RT-qPCR (quantitative reverse transcription PCR) and western blot analyses. Moreover, EdU (5-ethynyl-2′-deoxyuridine) detection and Oil Red O staining showed a decrease (P) in cell proliferation and lipid accumulation, respectively. The opposite trends (P) were obtained after transfection with miR-369-3p inhibitors. In conclusion, the results showed that miR-369-3p can inhibit the proliferation and differentiation of AFWS preadipocytes, providing a theoretical basis to further explore the molecular mechanism of fat deposition in sheep and other domestic animals.

Abstract Background Ordered transposon-insertion collections, in which specific transposon-insertion mutants are stored as monocultures in a genome-scale collection, represent a promising tool for genetic dissection of human gut microbiota members. However, publicly available collections are scarce and the construction methodology remains in early stages of development. Results Here, we describe the assembly of a genome-scale ordered collection of transposon-insertion mutants in the model gut anaerobe Bacteroides thetaiotaomicron VPI-5482 that we created as a resource for the research community. We used flow cytometry to sort single cells from a pooled library, located mutants within this initial progenitor collection by applying a pooling strategy with barcode sequencing, and re-arrayed specific mutants to create a condensed collection with single-insertion strains covering >2500 genes. To demonstrate the potential of the condensed collection for phenotypic screening, we analyzed growth dynamics and cell morphology. We identified both growth defects and altered cell shape in mutants disrupting sphingolipid synthesis and thiamine scavenging. Finally, we analyzed the process of assembling the B. theta condensed collection to identify inefficiencies that limited coverage. We demonstrate as part of this analysis that the process of assembling an ordered collection can be accurately modeled using barcode sequencing data. Conclusion We expect that utilization of this ordered collection will accelerate research into B. theta physiology and that lessons learned while assembling the collection will inform future efforts to assemble ordered mutant collections for an increasing number of gut microbiota members.

Abstract In analogy with GRB 190114C, we here analyze the ultrarelativistic prompt emission (UPE) of GRB 180720B observed in the rest-frame time interval $$t_{\mathrm{rf}}=4.84$$ t rf = 4.84 –10.89 s by Fermi-GBM. We reveal the UPE hierarchical structure from the time-resolved spectral analysis performed in time sub-intervals: the spectrum in each shorter time interval is always fitted by a composite blackbody plus cutoff power-law model. We explain this structure with the inner engine of binary-driven hypernova (BdHN) model operating in a quantum electrodynamics (QED) regime. In this regime, the electric field induced by the gravitomagnetic interaction of the newborn Kerr BH with the surrounding magnetic field is overcritical, i.e., $$|\mathbf{E}|\ge E_c$$ | E | ≥ E c , where $$E_c=m_e^2 c^3/(e\hbar )$$ E c = m e 2 c 3 / ( e ħ ) . The overcritical field polarizes the vacuum leading to an $$e^+~e^-$$ e + e - pair plasma that loads baryons from the surroundings during its expansion. We calculate the dynamics of the self-acceleration of the pair-electromagnetic-baryon (PEMB) pulses to their point of transparency. We characterize the quantum vacuum polarization process in the sequences of decreasing time bins of the UPE by determining the radiation timescale, Lorentz factors, and transparency radius of the PEMB pulses. We also estimate the strength of the surrounding magnetic field $$\sim 10^{14}$$ ∼ 10 14 G, and obtain a lower limit to the BH mass, $$M=2.4~M_\odot $$ M = 2.4 M ⊙ , and correspondingly an upper limit to the spin, $$\alpha = 0.6$$ α = 0.6 , from the conditions that the UPE is powered by the Kerr BH extractable energy and its mass is bound from below by the NS critical mass.

Perfect absorption can be obtained for a single port device, or a device with multiple incident beams, but for multiport devices, the absorption is limited to around 50%. In this work, Rao et al. overcome this limitation, demonstrating near perfect absorption in a two port cavity magnon system.

Aluminum (Al) alloys have a multitude of applications, notably in the automotive, aerospace and coating industries, yet they exhibit significantly lower mechanical strength than conventional steels. Nanotwins drastically improve mechanical strength while retaining ductility. However, the high SFE of Al largely prevents twinning. Here, we synthesize Al-Zr alloy films containing an abundance of incoherent twin boundaries and 9R phases. These alloys exhibit an extended solid solubility of Zr, retaining a columnar nanotwinned structure across all compositions. These films reach a hardness up to 4.2 GPa with 10 at% Zr and demonstrate the capacity for producing strong Al alloys with nanotwins.

Numerical air quality models (AQMs) have been applied more frequently over the past decade to address diverse scientific and regulatory issues associated with deteriorated air quality in China. Thorough evaluation of a model's ability to replicate monitored conditions (i.e., a model performance evaluation or MPE) helps to illuminate the robustness and reliability of the baseline modeling results and subsequent analyses. However, with numerous input data requirements, diverse model configurations, and the scientific evolution of the models themselves, no two AQM applications are the same and their performance results should be expected to differ. MPE procedures have been developed for Europe and North America, but there is currently no uniform set of MPE procedures and associated benchmarks for China. Here we present an extensive review of model performance for fine particulate matter (PM2.5) AQM applications to China and, from this context, propose a set of statistical benchmarks that can be used to objectively evaluate model performance for PM2.5 AQM applications in China. We compiled MPE results from 307 peer-reviewed articles published between 2006 and 2019, which applied five of the most frequently used AQMs in China. We analyze influences on the range of reported statistics from different model configurations, including modeling regions and seasons, spatial resolution of modeling grids, temporal resolution of the MPE, etc. Analysis using a random forest method shows that the choices of emission inventory, grid resolution, and aerosol- and gas-phase chemistry are the top three factors affecting model performance for PM2.5. We propose benchmarks for six frequently used evaluation metrics for AQM applications in China, including two tiers – “goals” and “criteria” – where goals represent the best model performance that a model is currently expected to achieve and criteria represent the model performance that the majority of studies can meet. Our results formed a benchmark framework for the modeling performance of PM2.5 and its chemical species in China. For instance, in order to meet the goal and criteria, the normalized mean bias (NMB) for total PM2.5 should be within 10 % and 20 %, while the normalized mean error (NME) should be within 35 % and 45 %, respectively. The goal and criteria values of correlation coefficients for evaluating hourly and daily PM2.5 are 0.70 and 0.60, respectively; corresponding values are higher when the index of agreement (IOA) is used (0.80 for goal and 0.70 for criteria). Results from this study will support the ever-growing modeling community in China by providing a more objective assessment and context for how well their results compare with previous studies and to better demonstrate the credibility and robustness of their AQM applications prior to subsequent regulatory assessments.

The construction of large reservoirs results in the formation of tributary bays, and tributary bays are inevitably influenced by backwater jacking and intrusions from the main reservoir. In this paper, a typical tributary bay (Tangxi River) of the Three Gorges Reservoir (TGR) was selected to study the hydrodynamic and environmental characteristics of a tributary bay influenced by the jacking and intrusions from the main reservoir. The flow field, water temperature, and water quality of Tangxi River were simulated using the hydrodynamic and water quality model CE-QUAL-W2 (thomas and Scott, 2008), and the eutrophication status of the tributary bay was also evaluated. The results showed that the main reservoir had different effects on its tributary bay in each month. The tributary bay was mainly affected by backwater jacking from the main reservoir when the water level of the main reservoir dropped and by intrusions from the main reservoir when the water level of the main reservoir rose. An obvious water quality concentration boundary existed in the tributary bay, which was consistent with the regional boundary in the flow field. The flow field and water quality on both sides of the boundary were quite different. The results of this study can help us figure out how the backwater jacking and intrusions from the main reservoir influence the hydrodynamic and water environment characteristics of the tributary bay and provide guidance for water environment protection in tributary bays.

Abstract A new physics scenario shows that four-fermion operators of Nambu-Jona-Lasinio (NJL) type have a strong-coupling UV fixed point, where composite fermions F (bosons $$\Pi $$ Π ) form as bound states of three (two) SM elementary fermions and they couple to their constituents via effective contact interactions at the composite scale $$\Lambda \approx {{{\mathcal {O}}}} $$ Λ≈O (TeV). We present a phenomenological study to investigate such composite particles at the LHC by computing the production cross sections and decay widths of composite fermions in the context of the relevant experiments at the LHC with pp collisions at $$\sqrt{s}=13$$ s=13 TeV and $$\sqrt{s}=14$$ s=14 TeV. Systematically examining all the different composite particles F and the signatures with which they can manifest, we found a vast spectrum of composite particles F that has not yet been explored at the LHC. Recasting the recent CMS results of the resonant channel $$pp\rightarrow e^+F \rightarrow e^+e^- q\bar{q}'$$ pp→e+F→e+e-qq¯′ (as $$F=E$$ F=E ), we find that the composite fermion mass $$m_F$$ mF below 4.25 TeV is excluded for $$\Lambda $$ Λ /$$m_F$$ mF = 1. We further highlight the region of parameter space where this specific composite particle F can appear using 3 $$\hbox {ab}^{-1}$$ ab-1 , expected by the High-Luminosity LHC, computing 3 and 5 $$\sigma $$ σ contour plots of its statistical significance.

Binary-driven hypernova (BdHN) models have been adopted to explain the observed properties of long gamma-ray bursts (GRBs). Here, we perform a comprehensive data analysis (temporal and spectral analysis, GeV emission, and afterglow) on GRB 130427A, GRB 160509A, and GRB 160625B. We identify three specific episodes characterized by different observational signatures and show that these episodes can be explained and predicted to occur within the framework of the BdHNe I model, as first observed in GRB 190114C and reported in an accompanying paper. Episode 1 includes the “SN-rise” with the characteristic cutoff power-law spectrum; Episode 2 is initiated by the moment of formation of the black hole, coincident with the onset of the GeV emission and the ultrarelativistic prompt emission phase, and is characterized by a cutoff power law and blackbody spectra; Episode 3 is the “cavity,” with its characteristic featureless spectrum.

Abstract Background Consumption of moldy food has previously been identified as a risk factor for esophageal squamous cell carcinoma (ESCC) in high-risk countries; however, what contributing roles these dietary carcinogenic mycotoxins play in the etiology of ESCC are largely unknown. Methods A mycotoxin biomarker-incorporated, population-based case-control study was performed in Huaian area, Jiangsu Province, one of the two high-risk areas in China. Exposure biomarkers of aflatoxins (AF) and fumonisins (FN) were quantitatively analyzed using HPLC-fluorescence techniques. Results Among the cases (n = 190), the median levels of AF biomarker, serum AFB1-lysine adduct, and FN biomarker, urinary FB1, were 1.77 pg/mg albumin and 176.13 pg/mg creatinine, respectively. Among the controls (n = 380), the median levels of AFB1-lysine adduct and urinary FB1 were 1.49 pg/mg albumin and 56.92 pg/mg creatinine, respectively. These mycotoxin exposure biomarker levels were significantly higher in cases as compared to controls (p

Background: Klinefelter’s Syndrome (KS) is rarely reported in China, which is associated with insufficient sperm production and infertility in male patients. Despite the fact that infertility treatments, such as intracytoplasmic sperm injection (ICSI) and preimplantation genetic diagnosis (PGD), have been widely used in KS population, almost all these patients have to use donor semen in China to establish successful pregnancies nowadays. Case Report: The authors report a case of KS in a patient with unremarkable characteristics except for oligospermia. The patient presented to this center with infertility and the chromosome analysis demonstrated a non-mosaic 47, XXY karyotype. Further testing showed no deletions in the SRY, AZF-a, AZF-b, and AZF-c genes. Finally, the patient successfully impregnated the partner, and then the partner delivered a healthy male neonate. The patient became fertile through ICSI, together with cryopreservation of a small number of spermatozoa after the first blastocyst transfer. Conclusion: This report further confirms that KS men can father their own healthy children. While adequate sperm cryopreservation and blastocyst transfers are strongly recommended. Nevertheless, it is necessary for such couples to be offered extensive genetic counseling before pregnancy and prenatally.

In-core or cladding structural materials exposed to heavy ion irradiation often suffer serious irradiation-induced damages. Introducing defect sinks can effectively mitigate irradiation-induced degradation in materials. Here, we investigated the radiation response of additively manufactured 316 austenitic stainless steel with high-density solidification cellular structures via in situ Kr++ irradiation at 400°C to 5 dpa. The study shows that the cellular walls with trapped dislocations can serve as effective defect sinks, thus reduce dislocation loop density compared with the conventional coarse-grained counterparts. This study provides a positive step for the potential applications of radiation-resistant, additively manufactured steels in advanced nuclear reactors.

Aluminum (Al) alloys have been widely used in the transportation industry. However, most high-strength Al alloys to date have limited mechanical strength, on the order of a few hundred MPa, which is much lower than the flow stress of high-strength steels. In this study, we show the fabrication of nanocrystalline Al alloys with high-density growth twins enabled by a few atomic percent of Co solute. In situ uniaxial compression tests show that the flow stress of Al–Co solid solution alloys exceeds 1.5 GPa, while good work hardening capability is maintained. This study provides a new perspective on the design of high-strength Al alloys for various applications.

Background:. The requirement for postmastectomy radiation therapy (PMRT) at the time of mastectomy is often unknown. Autologous reconstruction is preferred in the setting of radiotherapy by providing healthy vascularized tissue to the chest. To maximize mastectomy skin preservation, tissue expander (TE) placement maintains the breast pocket until definitive reconstruction. This study aims to compare outcomes of skin-preserving delayed versus standard delayed autologous breast reconstruction in the setting of PMRT. Methods:. A retrospective review of a prospective database was performed of two patient cohorts at a single center between 2006 and 2016. Inclusion criteria were locally advanced breast cancer patients who completed PMRT and free autologous reconstruction. Primary outcomes were major intraoperative and postoperative TE and flap complications. Results:. Over 10 years, 241 patients underwent mastectomy and PMRT. Standard delayed autologous breast reconstruction was performed in 131 breasts (non-TE group). Skin-preserving delayed autologous reconstruction was performed in 113 breasts (TE group). The TE group was associated with a higher incidence of intraoperative complications during flap reconstruction (P = 0.002) and had a higher venous thrombosis incidence than the non-TE cohort (P = 0.007). Other major postoperative complications were not significantly different between the two groups. TE patients had 7.5 times higher risk of intraoperative complications and an 18.6% TE loss rate. Conclusions:. We identified higher intraoperative flap complications and a high rate of TE loss in patients who underwent skin-preserving delayed autologous breast reconstruction. The benefit of mastectomy skin preservation needs to be weighed against the increased risk of TE loss and higher rates of flap thrombosis.

Background:. One-stage augmentation mastopexy is a challenging procedure, with the highest cited revision rates in plastic surgery. This is because when mastopexy and augmentation are performed together, they lead to opposing forces, which must be balanced carefully to avoid complications. The goal of this study was to revisit a previously described predictable and safe approach to one-stage augmentation mastopexy, and provide long-term updated results. Methods:. One hundred seventy-one patients who underwent augmentation mastopexy, performed by a single surgeon (R.J.R.), were included in this retrospective review between January 2005 and January 2019. Wise pattern mastopexy with wide pedicle was performed before placement of a small subpectoral implant. Demographic information, preoperative breast measurements, intraoperative technique, implant choice, and postoperative complications were analyzed. Specifically, postoperative measurement of vertical limbs was performed to assess long-term elongation of the lower breast pole. Results:. Cumulative complication rate was 11.7%. This rate decreased to 6% in the last 88 patients in this series as the technique matured. The most common complication was revision for implant size exchange. Long-term follow-up demonstrated elongation of nipple-to-inframammary fold distance by 1.0–2.2 cm. There was no recurrence of ptosis requiring reoperation. Conclusions:. This one-stage augmentation mastopexy technique provides a safe and reliable surgical approach with predictable and minimal elongation of the lower breast pole. The reoperation rate of this technique is less than half of >20% revision rate currently cited in the literature.

Dedicated experimental and modeling research studies on the performance of superconducting cable-in-conduit conductor (CICC) have been massively performed and are still ongoing in order to determine the operational limits of the conductors and to optimize their design. Strand strain distribution and crack formation in the filaments after cabling and compaction, and under cooling down and electromagnetic load have been considered as the main cause for the degradation of the CICC’s transport properties. In combination with the strain maps generated by the mechanical model MULTIFIL and the electromagnetic code JackPot with the basic electrical and strain properties of the superconducting strand, the current sharing temperature (Tcs) of the CICC of the ITER Central Solenoid has been simulated and analyzed. A quantitative analysis of the Tcs degradation due to strain variation and filament fracture, respectively, is still missing. Here, the approach of analyzing the performance of CICC (e.g., the short samples tested in the SULTAN facility, or the full-size CICC used in real magnets) has been presented. Consequently, the effect of filament fracture on the cable Tcs has been investigated and turns out to be limited. Instead, the dominant mechanism behind the degradation of the transport properties of ITER type Nb3Sn CICCs is shown to be the broadening and shift in the strain distribution of the superconducting filaments.

Slope aspect is an important topographic factor in the micro-ecosystem environment, but its effect on the microbial properties of grassland rhizospheric soil (RS) and non-rhizospheric soil (NRS) remain unclear. A field experiment was conducted at the Ansai Research Station on the Loess Plateau in China to test the influence of slope aspects (south-facing, north-facing, and northwest-facing slopes, all with Artemisia sacrorum as the dominant species) on RS and NRS microbial biomass carbon (MBC) contents, phospholipid fatty acid (PLFA) contents, and the rhizospheric effect (RE) of various microbial indices. Soil samples were collected from the three slope aspects, including rhizospheric and non-rhizospheric region, and analyzed to determine the various related microbial indices. The results showed that MBC content differed significantly among the slope aspects in RS but not in NRS, and the RE for MBC content in the south-facing slope was larger than that in the north-facing slope. RS total, bacterial, and Gram-positive bacterial PLFA contents in the south-facing slope were significantly lower than those in the north- and northwest-facing slopes, and RS Gram-negative bacterial (G−) and actinomycete PLFA contents in the south-facing slope were significantly lower than those in the north-facing slope. In contrast, NRS total, bacterial, and G− PLFA contents in the north-facing slope were significantly higher than those in the south- and northwest-facing slopes, and NRS fungal and actinomycete PLFA contents in the north- and south-facing slopes were significantly higher than those in the northwest-facing slope. RE for all PLFA contents except fungal in the northwest-facing slope were higher than those in the south-facing slope. Slope aspect significantly but differentially affected the microbial properties in RS and NRS, and the variable influence was due to an evident RE for most microbial properties.

Fundamental Matrix Estimation is of vital importance in many vision applications and is a core part of 3D reconstruction pipeline. Radial distortion makes the problem to be numerically challenging. We propose a novel robust method for radial fundamental matrix estimation. Firstly, two-sided radial fundamental matrix is deduced to describe epipolar geometry relationship between two distorted images. Secondly, we use singular value decomposition to solve the final nonlinear minimization solutions and to get the outliers removed by multiplying a weighted matrix to the coefficient matrix. In every iterative step, the criterion which is the distance between feature point and corresponding epipolar line is used to determine the inliers and the weighted matrix is update according to it. The iterative process has a fast convergence rate, and the estimation result of radial fundamental matrix remains stable even at the condition of many outliers. Experimental results prove that the proposed method is of high accuracy and robust for estimating the radial fundamental matrix. The estimation result of radial fundamental matrix could be served as the initialization for structure from motion.

Stokes polarimeters and scanning slit optical beam profilers are used to measure the polarization properties and optical spot intensities of a laser beam, which go through the micromodulator by the Z-scanning method. The polarization properties of a S-polarized and a P-polarized light are researched. The optical intensities of laser beam are obtained for S-polarized light by the Z-scanning method. The results show that the groove films can affect the polarization properties of the P-polarized light but do not change the polarization properties of the S-polarized light. The optical spot intensity of S-polarized light can be changed with the help of groove films as the scattering effect.

Aflatoxins B1 (AFB1), deoxynivalenol (DON), fumonisin B1 (FB1), T-2 toxin (T-2), and zearalenone (ZEA) are the major foodborne mycotoxins of public health concerns. In the present study, the multiple toxic endpoints of these naturally-occurring mycotoxins were evaluated in Caenorhabditis elegans model for their lethality, toxic effects on growth and reproduction, as well as influence on lifespan. We found that the lethality endpoint was more sensitive for T-2 toxicity with the EC50 at 1.38 mg/L, the growth endpoint was relatively sensitive for AFB1 toxic effects, and the reproduction endpoint was more sensitive for toxicities of AFB1, FB1, and ZEA. Moreover, the lifespan endpoint was sensitive to toxic effects of all five tested mycotoxins. Data obtained from this study may serve as an important contribution to knowledge on assessment of mycotoxin toxic effects, especially for assessing developmental and reproductive toxic effects, using the C. elegans model.

Glass-forming ability (GFA) is crucial for designing bulk metallic glasses. In this work, it was found that when the content of the solvent element with an atomic radius larger than 1.58 Å in one ternary alloy system is fixed, their entropy of mixing (ΔSmix) vs. the enthalpy of mixing (ΔHmix) curve display a slant arc shape. The compositions locating around the inflection point of each ΔHmix vs. ΔSmix curve usually show an optimal GFA. Its feasibility was verified in Zr-, La-, and Ca-based ternary systems. By considering both calculated inflection points and experimental results, the optimizing glass-forming compositions can be roughly estimated by a proposed formula under limited conditions. Our studies could provide a simple method for preliminarily selecting good glass-formers when the content of the solvent element in one ternary alloy system is fixed.

ABSTRACT The high mutation rates of RNA viruses lead to rapid genetic diversification, which can enable cooperative interactions between variants in a viral population. We previously described two distinct variants of H3N2 influenza virus that cooperate in cell culture. These variants differ by a single mutation, D151G, in the neuraminidase protein. The D151G mutation reaches a stable frequency of about 50% when virus is passaged in cell culture. However, it is unclear whether selection for the cooperative benefits of D151G is a cell culture phenomenon or whether the mutation is also sometimes present at appreciable frequency in virus populations sampled directly from infected humans. Prior work has not detected D151G in unpassaged clinical samples, but those studies have used methods like Sanger sequencing and pyrosequencing, which are relatively insensitive to low-frequency variation. We identified nine samples of human H3N2 influenza virus collected between 2013 and 2015 in which Sanger sequencing had detected a high frequency of the D151G mutation following one to three passages in cell culture. We deep sequenced the unpassaged clinical samples to identify low-frequency viral variants. The frequency of D151G did not exceed the frequency of library preparation and sequencing errors in any of the sequenced samples. We conclude that passage in cell culture is primarily responsible for the frequent observations of D151G in recent H3N2 influenza virus strains. IMPORTANCE Viruses mutate rapidly, and recent studies of RNA viruses have shown that related viral variants can sometimes cooperate to improve each other’s growth. We previously described two variants of H3N2 influenza virus that cooperate in cell culture. The mutation responsible for cooperation is often observed when human samples of influenza virus are grown in the lab before sequencing, but it is unclear whether the mutation also exists in human infections or is exclusively the result of lab passage. We identified nine human isolates of influenza virus that had developed the cooperating mutation after being grown in the lab and performed highly sensitive deep sequencing of the unpassaged clinical samples to determine whether the mutation existed in the original human infections. We found no evidence of the cooperating mutation in the unpassaged samples, suggesting that the cooperation arises primarily under laboratory conditions.