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Repetitively pulsed discharge is an emerging non-thermal plasma technology in the chemistry field given its advantages of high electron energy and moderate gas temperature. The focus of this paper is on the temporal evolution of physical and chemical processes in the plasma-assisted non-oxidative conversion of methane (CH4). Positive and negative streamer discharge plasmas were generated by a microsecond-pulse power source (pulse rising time ~500 ns and full width at half maximum ~8 μs) in a well-designed dielectric barrier discharge reactor. The performance of CH4 conversion (conversion rate, product yield, energy conversion efficiency, etc) was investigated in the first instance. A CH4 conversion rate of 6.2%–9.6% was acquired in the negative streamer discharges, which is on average 6% higher than that in the positive streamer discharges. To explain this phenomenon, the temporal evolution of voltage–current waveforms and ultrafast ICCD photographs and optical emission spectra were recorded. As expected, significant differences between the two different forms of discharges were found. Compared with those of the positive streamer discharges, characteristics of only one, big breakdown, higher initial voltage and current peak, a more stable and nearly uniform luminescent process, and higher CH (A2Δ  −  X2Π) emission intensity and rotational temperature were observed in the negative streamer discharges, which coincide with the promotion of CH4 conversion performance. A simplified chemical kinetics analysis of CH4 discharge was also implemented to demonstrate the influence of characteristic differences on CH4 conversion performance. [ABSTRACT FROM AUTHOR]

For absorption linewidth inversion with wavelength modulation spectroscopy (WMS), an optimized WMS spectral line fitting method was demonstrated to infer absorption linewidth effectively, and the analytical expressions for relationships between Lorentzian linewidth and the separations of first harmonic peak-to-valley and second harmonic zero-crossing were deduced. The transition of CO2 centered at 4991.25 cm−1 was used to verify the optimized spectral fitting method and the analytical expressions. Results showed that the optimized spectra fitting method was able to infer absorption accurately and compute more than 10 times faster than the commonly used numerical fitting procedure. The second harmonic zero-crossing separation method calculated an even 6 orders faster than the spectra fitting without losing any accuracy for Lorentzian dominated cases. Additionally, linewidth calculated through second harmonic zero-crossing was preferred for much smaller error than the first harmonic peak-to-valley separation method. The presented analytical expressions can also be used in on-line optical sensing applications, electron paramagnetic resonance, and further theoretical characterization of absorption lineshape. [ABSTRACT FROM AUTHOR]

An effective vaccine for hepatitis C virus (HCV) is a major unmet need, and it requires an antigen that elicits immune responses to key conserved epitopes. Based on structures of antibodies targeting HCV envelope glycoprotein E2, we designed immunogens to modulate the structure and dynamics of E2 and favor induction of broadly neutralizing antibodies (bNAbs) in the context of a vaccine. These designs include a point mutation in a key conserved antigenic site to stabilize its conformation, as well as redesigns of an immunogenic region to add a new N-glycosylation site and mask it from antibody binding. Designs were experimentally characterized for binding to a panel of human monoclonal antibodies (HMAbs) and the coreceptor CD81 to confirm preservation of epitope structure and preferred antigenicity profile. Selected E2 designs were tested for immunogenicity in mice, with and without hypervariable region 1, which is an immunogenic region associated with viral escape. One of these designs showed improvement in polyclonal immune serum binding to HCV pseudoparticles and neutralization of isolates associated with antibody resistance. These results indicate that antigen optimization through structure-based design of the envelope glycoproteins is a promising route to an effective vaccine for HCV. [ABSTRACT FROM AUTHOR]

Salivary glands are a major component of the mucosal immune system that confer adaptive immunity to mucosal pathogens. As previously demonstrated, immunization of the submandibular gland with tissue culture-derived murine cytomegalovirus (tcMCMV) or replication-deficient adenoviruses expressing individual murine cytomegalovirus (MCMV) genes protected mice against a lethal MCMV challenge. Here, we report that salivary gland inoculation of BALB/cByJ mice with tcMCMV or recombinant adenoviruses differentially activates T helper (Th)1, -2, and -17 cells in the salivary glands vs. the associated lymph nodes. After inoculation with tcMCMV, lymphocytes from the submandibular gland preferentially express the transcription factor T-cell-specific T-box transcription factor (T-bet), which controls the expression of the hallmark Th1 cytokine, IFN-γ. Lymphocytes from the periglandular lymph nodes (PGLNs) express both T-bet and GATA-binding protein 3 (GATA3), which promotes the secretion of IL-4, -5, and -10 from Th2 cells. In contrast, after inoculation with replication-deficient adenoviruses, lymphocytes from the submandibular gland express T-bet, GATA3, and RAR-related orphan receptor γ, thymus-specific isoform (RORγt) (required for differentiation of Th17 cells) and forkhead box P3 (Foxp3) (required for the differentiation of regulatory T cells). Lymphocytes from the PGLNs were not activated. The differential induction of Th responses in the salivary gland vs. the PGLNs after inoculation with attenuated virus vs. a nominal protein antigen supports the use of the salivary as an alternative mucosal route for administering vaccines. [ABSTRACT FROM AUTHOR]

The monoclinic (M) phases in high-performance relaxor-based ferroelectric single crystals have been recognized to be a vital structural factor for the outstanding piezoelectric property. However, due to the complexity of the structure in M phases, the understanding about it is still limited. In this paper, the local twin domains and tip-voltage-induced domain switching of the MC phase in Pb(Mg1/3Nb2/3)O3-0.34PbTiO3 (PMN-0.34PT) single crystal have been intensively investigated by piezoresponse force microscopy (PFM). By theoretically analyzing the experimental patterns of domain walls on the (001)C face, the specific MC twin domains in the initial annealed state of a selected area have been clarified, and the polarization orientation of the MC phase in this sample is determined to be at an angle of 29° to the ≺001≻C directions. In addition, based on the evolution of domains and the motion of domain walls under the step-increased PFM tip dc voltage (Vdc), the switching process and features of different types of MC domain variants are visually revealed. [ABSTRACT FROM AUTHOR]

Continually emerging SARS-CoV-2 variants of concern that can evade immune defenses are driving recurrent epidemic waves of COVID-19 globally. However, the impact of measures to contain the virus and their effect on lineage diversity dynamics are poorly understood. Here, we jointly analyzed international travel, public health and social measures (PHSM), COVID-19 vaccine rollout, SARS-CoV-2 lineage diversity, and the case growth rate (GR) from March 2020 to September 2022 across 63 countries. We showed that despite worldwide vaccine rollout, PHSM are effective in mitigating epidemic waves and lineage diversity. An increase of 10,000 monthly travelers in a single country-to-country route between endemic countries corresponds to a 5.5% (95% CI: 2.9 to 8.2%) rise in local lineage diversity. After accounting for PHSM, natural immunity from previous infections, and waning immunity, we discovered a negative association between the GR of cases and adjusted vaccine coverage (AVC). We also observed a complex relationship between lineage diversity and vaccine rollout. Specifically, we found a significant negative association between lineage diversity and AVC at both low and high levels but not significant at the medium level. Our study deepens the understanding of population immunity and lineage dynamics for future pandemic preparedness and responsiveness. [ABSTRACT FROM AUTHOR]

As the deposition of elemental sulfur may cause severe corrosion perforation risk in heat exchanger tube, it is necessary to clarify the suitability of commonly used heat exchanger tube materials in elemental sulfur - containing environments. In this paper, the corrosion behaviors under high - temperature environment containing elemental sulfur of three commonly used materials for heat exchanger tube, including 20# steel, 316L austenitic stainless steel and 2205 duplex stainless steel, were investigated by immersion test with the help of scanning electron microscope (SEM), energy dispersive spectroscopy (EDS) and X - ray diffractometer (XRD). Results showed that: in the 220 ℃ medium of condensate water containing 2% (mass fraction ) elemental sulfur, the average corrosion rate of 20# steel could reach 10.520 mm/a, the pitting corrosion rate of 316L stainless steel could reach 0.470 mm/a, and the corrosion rate of 2205 duplex stainless steel was only 0.036 mm/a. In addition, the main corrosion product of all the three materials was FeS2. The corrosion film on the surface of 20# steel was loose and porous, thus could only provide a poor protection. The corrosion film of 316L stainless steel and 2205 duplex stainless steel had better uniformity and density than that of 20# steel. Furthermore, 2205 duplex stainless steel could meet the service requirements of heat exchanger tubes under the as - mentioned working condition.

• Five machine learning algorithms are used to predict dairy cow feed intake. • There is not a simple linear relationship between feed intake and predictors. • Dietary ingredients can improve the accuracy of feed intake prediction. • Dietary ingredients can be added to smart monitoring devices to optimize performance. The individual feed intake of dairy cows is an indicator of oestrus and health status and can be used as an abnormality warning in health monitoring. However, existing methods for monitoring individual feed intake are limited by the feeding environment and equipment and are difficult to apply in commercial production. In this experiment, a feed intake monitoring system for dairy cows was used to determine the daily feed intake of 10 dairy cows. The dairy cows were fed 8 diets with different concentration-to-forage ratios according to different phases or time intervals. The adaptation period of the cows to each diet was 7 days, and the trial period was 7 days. Smart collars were used to monitor the daily eating time and ruminating time of the dairy cows, which were used along with dietary components as input parameters to establish five feed intake prediction models: a linear regression model (LRM), an artificial neural network model, a support vector machine model, a K-nearest neighbour model and a chi-square automatic interaction detector model. The research results showed that R2 was 0.73 for the LRM and ≥0.82 for the other four models, which indicated that the relationship between feed intake and the predictors may not be a simple linear relationship. The five models had root mean square errors (RMSEs) ≤ 1.5 kg/d and standard deviations (SDs) ≤ 0.87 kg/d, and in external verification, the five models achieved R2 values ≥ 0.80, RMSEs ≤ 0.75 kg/d, and SDs ≤ 0.90 kg/d. This study shows that adding dietary ingredient data to collar-collected data can improve prediction model accuracy. [ABSTRACT FROM AUTHOR]

Neutral beam injection heating system is one of the main heating methods to improve the operating parameters of EAST plasma physics. However, the neutron emission intensity can reach up to 1014 n/s. Because of the neutral beam injection (NBI) with a larger open size, the neutrons stream along the NBI duct. That may affect the safe and stable operation for NBI. In this paper, by using Monte Carlo program MCNP and activation program FISPACT, the material activation of the NBI key components has been researched based on EAST neutral beam two-dimensional geometric model when the angle between the reverse beam and the coaxial beam is 112.5 degrees. The theoretical simulation results are in good agreement with the experimental measurements. The results show that 51Cr, 58Co and 54Mn with medium and long life have obvious peak value of gamma energy spectrum, which indicate that those nucleus are the main active nuclides of SS304 and copper. When EAST stopped operating for 5 min, the shut down dose rate generated by activated gamma photon had been reduced to the dose rate limit designed by International Thermonuclear Experimental Reactor. This work could provide a preliminary exploration for material activation and shutdown dose rate analysis of the fusion reactor neutral beam injection port.

Ubiquitin specific protease 26 (USP26) encodes a predicted protein containing his- and cys-domains that are conserved among deubiquitinating enzymes. USP26 is specifically expressed in testis tissue and is a potential infertility gene. In the present study, we performed genetic testing related to spermatogenesis impairment in a patient with idiopathic severe oligozoospermia to identify the cause. The patient underwent clinical examination and reproductive hormone testing. Genes associated with male infertility, including USP26, were assessed by targeted exome sequencing. A novel frameshift mutation, c.2195delT (p.Phe732Serfs*14), was identified in USP26. This frameshift mutation was located in residue 732 of USP26 gene, leading to loss of the conserved deubiquitinating enzyme His-domain and producing a truncated protein of 744 amino acids. Bioinformatics analysis revealed this mutation to be pathogenic. A novel framshift mutation c.2195delT (p.Phe732Serfs*14) in USP26 gene was reported to be associated with male infertility in a Chinese patient with severe oligozoospermia. [ABSTRACT FROM AUTHOR]

Multidomain relaxor-based ferroelectric single crystals (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT) have extraordinarily large electromechanical properties, but the origin of their giant piezoelectric properties is still not well understood. The Landau-like phenomenological theory is a feasible tool to study domain structures and their correlation with piezoelectric effects, but so far no expansion coefficients have been measured due to the phase mixture complication involved. In this work, the Landau free-energy expansion parameters for 0.70Pb(Mg1/3Nb2/3)O3-0.30PbTiO3 (PMN-0.30PT) single crystal were determined from the temperature-dependent polarization-electric field (P-E) hysteresis loops along [001]C and [011]C directions, and the rhombohedral (R) to tetragonal (T) phase-transition temperature. Using the obtained parameters, ferroelectric and dielectric properties were quantitatively calculated and compared with experiments. Good agreement was achieved in the temperature regions of T and R phases, but deviations were found in the cubic-phase temperature region since the contribution of polar nanoregions was not considered. In the phase-coexistence region from 73 to 93°C, the polarization and dielectric constant can be quantitatively explained with the volume fractions of the coexisting R and T phases predicted by the canonical distribution. These obtained parameters can help theoretical studies and simulations of these relaxor-based ferroelectric single crystals to reveal the correlation between domain microstructures and the origin of giant electromechanical properties of multidomain PMN-PT single crystals. [ABSTRACT FROM AUTHOR]

Lactic acid bacteria are important fermentation strains, and improving their freeze-drying survival rate (FDSR) has become a hot research topic in recent years. In this research, we found that adding 0.1 g/L L-glutamate to culture medium improved the FDSR of four strains of L. plantarum. Using L. plantarum LIP-1 as an example, we explored the internal mechanism of this phenomenon. L-glutamate had this effect through two metabolic pathways. First, it made the strain grow rapidly and produce more acid, resulting in a rapid decline of pH in the culture environment. The acidic environment led to the upregulation of the dnaK gene and secG gene expression, increased DnaK protein levels, promoted its anchoring effect on the cell membrane, and enhanced the integrity of the cell membrane. Second, it upregulated the expression of the murL , murD , and vanY genes, increased peptidoglycan synthesis, and increased cell wall integrity. In sum, the strain obtained a higher FDSR by adjusting the cell membrane and cell wall structure using L-glutamate. This study provides a new method for improving the FDSR of lactic acid bacteria. • L-glutamate in the medium improved the freeze-drying survival rate of the strain. • L-glutamate made the strain produce more acid, which up-regulated the dnaK and secG gene and enhanced the integrity of the cell membrane. • L-glutamate up-regulated murL , murD , and vanY genes, which enhanced the cell-wall integrity. • These adjustments improved the freeze-drying resistance of the strain. [ABSTRACT FROM AUTHOR]

Domain pattern variations with temperature were studied by polarizing light microscopy for the morphotropic phase boundary composition 0.67Pb(Mg1/3Nb2/3)O3-0.33PbTiO3 (PMN-0.33PT) single crystal. At room temperature, the monoclinic MA phase is the dominant phase in the unpoled crystal, which coexists with a small fraction of the tetragonal (T) phase. The orientation of spontaneous polarization was calculated to be ∼4.8° away from the pseudocubic (111)C in the {001}C plane family. Under an electric field of 6 kV/cm along [011]C, a single domain orthorhombic (O) phase was induced but partially switched back to MA a few hours after the removal of the E field. It was found that the temperature induced phase transition sequence of the [011]C poled PMN-0.33PT single crystal is strongly hysteretic. On heating, the phase transition sequence is as follows: coexistence of O phase and MA→rhombohedral→monoclinicMC→cubic(C). On cooling, the phase transition sequence is given by C→T→MA. The complete set of dielectric, piezoelectric, and elastic constants for the [011]C poled PMN-0.33PT single crystal was measured, which showed the strong feature of the single domain O phase with high shear (d15=2321pC/N,d24=1941pC/N) and low longitudinal piezoelectric coefficients (d33=165pC/N). [ABSTRACT FROM AUTHOR]

• Buffer salt could improve the freeze-drying survival rate and biofilm formation. • K+ in buffer salt up-regulated the luxS and cysE , and biofilm formation increased. • The survival rate was decreased with the inhibition of biofilm formation. • The effect of buffer salt on the survival rate was related to biofilm formation. Lactic acid bacteria can improve their resistance to adverse environments through the formation of biofilm. This study found that adding different buffer salts in culture medium had a great impact on the freeze-drying survival rate of the Lactobacillus plantarum LIP-1, which could be linked to biofilm formation. Transcriptome data showed that potassium ions in buffer salt increased the expression of the luxS gene in the LuxS/autoinducer-2 (AI-2) quorum sensing system and increase synthesis of the quorum sensing signal AI-2. The AI-2 signal molecules up-regulated the cysE gene, which helps to promote biofilm formation. By adding a biofilm inhibitor, d -galactose, and performing a real-time quantitative polymerase chain reaction experiment, we found that d -galactose could down-regulated the luxS and cysE genes, reduced biofilm formation, and decreased the freeze-drying survival rate. The results of this study showed that promoting biofilm formation using appropriate buffer salts may lead to better freeze-drying survival rates. [ABSTRACT FROM AUTHOR]

The phase-transition sequence of 0.63Pb(Mg1/3Nb2/3)-0.37PbTiO3 (PMN-0.37PT) single crystals driven by the electric (E) field and temperature is comprehensively studied. Based on the strain-E field loop, polarization-E field loop, and the evolution of domain configurations, the E field along the [011]C induced phase transitions have been confirmed to be as follows: tetragonal (T) → monoclinic (MC)→ single domain orthorhombic (O) phase. As the E field decreases, the induced O phase cannot be maintained and transformed to the MC phase, then to the coexistence state of MC and T phases. In addition, the complete sets of dielectric, piezoelectric, and elastic constants for the [011]C-poled domain-engineered PMN-0.37PT single crystal were measured at room temperature, which show high longitudinal dielectric, piezoelectric, and electromechanical properties (ɛT33=10661,d33=1052pC/N, and k33=0.766). Our results revealed that the MC phase plays an important role in the high electromechanical properties of this domain-engineered single crystal. The temperature dependence of the domain configuration revealed that the volume fraction of the MC phase decreases with temperature accompanied by the reduction of ɛT33,d31, and k31 due to the substantially smaller intrinsic properties of the T phase. [ABSTRACT FROM AUTHOR]

To compare the clinical efficacy of ultrasound cycloplasty (UCP) and endoscopic cyclophotocoagulation (ECP) in the treatment of secondary glaucoma. In a 12-month prospective single-center study, 22 patients with secondary glaucoma were treated by high-intensity focused ultrasound (HIFU), and 23 patients with secondary glaucoma were treated by a semiconductor laser. At the final follow-up, the two groups' surgical outcomes were compared. A complete success was defined as an intraocular pressure (IOP) reduction of at least 20% from baseline and an IOP of > 5 mmHg and ≦ 21 mmHg, while a qualified success was defined as an IOP reduction of at least 20% from baseline and an IOP of > 5 mmHg. The secondary outcome was the average IOP, number of drugs, and complications at each follow-up compared with the baseline. The average preoperative IOPs in the UCP and ECP groups were 36.4 ± 9.5 mmHg (n = 2.3 drops, n = 0.2 tablets) and 34.5 ± 11.7 mmHg (n = 2.0 drops, n = 0.3 tablets), respectively. In the last follow-up, the success rate of UCP was 54% (with a decrease of 32%) and that of ECP was 65% (with a decrease of 35%), and the P-value between the two groups was > 0.05. However, there was a difference in the average IOP between these two groups 1 day and 1 week after the operation, and the IOP reduction efficiency in the ECP group was better. However, the amount of drug used after these two surgeries was significantly reduced. There were fewer postoperative complications in the UCP group (18 cases) than in the ECP group (35 cases). Both UCP and ECP can effectively reduce IOP in secondary glaucoma, and ECP has a better effect at the early stages. However, UCP has higher safety and tolerance for patients., (© 2023. The Author(s).)

Purpose: To compare the clinical efficacy, safety, and histological effect between ultrasound cycloplasty (UCP) and cyclocryotherapy in the treatment of neovascular glaucoma., Methods: Two groups of neovascular glaucoma patients who underwent two types of treatment, respectively, namely, 26 patients treated by UCP and 23 by cyclocryotherapy, were treated and observed during the clinical study for six months. The primary outcome was evaluated by the surgical success, which was defined as the intraocular pressure (IOP) reduction of greater than or equal to 20% from the baseline and the IOP value of greater than 5 mmHg at the last follow-up. The secondary outcome referred to pain relief, complications, and the mean of the IOP at each follow-up. In the animal experiment, 18 New Zealand rabbits were divided into two groups and treated by UCP and cyclocryotherapy, respectively. The changes in the tissues and in the expression of matrix metalloproteinase-1 (MMP-1) were observed immediately., Results: The mean IOP baseline for the UCP and cyclocryotherapy groups was 54.6 ± 9.7 mmHg and 53.3 ± 11.7 mmHg, respectively. After six months of follow-up, the IOP value decreased to 30.3 ± 9.4 mmHg for the patients treated by UCP and to 30.4 ± 9.1 mmHg for those treated by cyclocryotherapy. The two groups achieved a satisfying success rate in the treatment of neovascular glaucoma of up to 70% at least. Vision impairment was observed in some patients treated with cyclocryotherapy, and these patients suffered from more complications and less pain relief than the patients who were treated with UCP. The histological study showed that the ciliary body was completely destroyed after cyclocryotherapy and that MMP-1 was found only in the ciliary muscle. After the UCP treatment, MMP-1 could still be found in the ciliary body, and only the double-layer epithelial cells presented with coagulative necrosis., Conclusion: The UCP treatment and cyclocryotherapy both showed good efficacy in significantly reducing the IOP. However, the UCP treatment was safer with less postoperative complications and adverse effects. Thus, the overall treatment effect of the UCP was more efficient than that of cyclocryotherapy., Competing Interests: The authors declare no conflicts of interest and no financial disclosures., (Copyright © 2020 Wang Ruixue et al.)