Protein design with a machine-learned potential about backbone designability.

Proteins are fundamental molecules that mediate diverse biological processes, and protein design can shed light on the molecular mechanisms underlying their biological functions. Huang and colleagues have developed a sequence-independent statistical model for de novo protein design using neural networks (NNs) to learn the distribution of backbone structures with minimal side-chain information.

Natural variation in WHITE-CORE RATE 1 regulates redox homeostasis in rice endosperm to affect grain quality.

Grain chalkiness reduces the quality of rice (Oryza sativa) and is a highly undesirable trait for breeding and marketing. However, the underlying molecular cause of chalkiness remains largely unknown. Here, we cloned the F-box gene WHITE-CORE RATE 1 (WCR1), which negatively regulates grain chalkiness and improves grain quality in rice. A functional A/G variation in the promoter region of WCR1 generates the alleles WCR1A and WCR1G, which originated from tropical japonica and wild rice Oryza rufipogon, respectively. OsDOF17 is a transcriptional activator that binds to the AAAAG cis-element in the WCR1A promoter. WCR1 positively affects the transcription of the metallothionein gene MT2b and interacts with MT2b to inhibit its 26S proteasome-mediated degradation, leading to decreased reactive oxygen species production and delayed programmed cell death in rice endosperm. This, in turn, leads to reduced chalkiness. Our findings uncover a molecular mechanism underlying rice chalkiness and identify the promising natural variant WCR1A, with application potential for rice breeding.

Irradiated engineered tumor cell-derived microparticles remodel the tumor immune microenvironment and enhance antitumor immunity.

Radiotherapy (RT), administered to roughly half of all cancer patients, occupies a crucial role in the landscape of cancer treatment. However, expanding the clinical indications of RT remains challenging. Inspired by the radiation-induced bystander effect (RIBE), we used the mediators of RIBE to mimic RT. Specifically, we discovered that irradiated tumor cell-released microparticles (RT-MPs) mediated the RIBE and had immune activation effects. To further boost the immune activation effect of RT-MPs to achieve cancer remission, even in advanced stages, we engineered RT-MPs with different cytokine and chemokine combinations by modifying their production method. After comparing the therapeutic effect of the engineered RT-MPs in vitro and in vivo, we demonstrated that tIL-15/tCCL19-RT-MPs effectively activated antitumor immune responses, significantly prolonged the survival of mice with malignant pleural effusion (MPE), and even achieved complete cancer remission. When tIL-15/tCCL19-RT-MPs were combined with PD-1 monoclonal antibody (mAb), a cure rate of up to 60% was achieved. This combination therapy relied on the activation of CD8+ T cells and macrophages, resulting in the inhibition of tumor growth and the establishment of immunological memory against tumor cells. Hence, our research may provide an alternative and promising strategy for cancers that are not amenable to conventional RT.

Abnormal upregulation of NUBP2 contributes to cancer progression in colorectal cancer.

Colorectal cancer (CRC), a digestive tract malignancy with high mortality and morbidity, lacks effective biomarkers for clinical prognosis due to its complex molecular pathogenesis. Nucleotide binding protein 2 (NUBP2) plays a vital role in the assembly of cytosolic Fe/S protein and has been implicated in cancer progression. In this study, we found that NUBP2 was highly expressed in CRC by TCGA database analysis. Subsequently, we verified the expression of NUBP2 in CRC tumor tissues and para-carcinoma tissues using IHC staining, and further investigated its association with clinicopathological parameters. In vitro cell experiments were conducted to assess the role of NUBP2 in CRC by evaluating cell proliferation, migration, and apoptosis upon NUBP2 dysregulation. Furthermore, we established a subcutaneous CRC model to evaluate the impact of NUBP2 on tumor growth in vivo. Additionally, we performed mechanistic exploration using a Human Phospho-Kinase Array-Membrane. Our results showed higher expression of NUBP2 in CRC tissues, which positively correlated with the pathological stage, indicating its involvement in tumor malignancy. Functional studies demonstrated that NUBP2 knockdown reduced cell proliferation, increased apoptosis, and impaired migration ability. Moreover, NUBP2 knockdown inhibited tumor growth in mice. We also observed significant changes in the phosphorylation level of GSK3ß upon NUBP2 knockdown or overexpression. Additionally, treatment with CHIR-99021 HCl, an inhibitor of GSK3ß, reversed the malignant phenotype induced by NUBP2 overexpression. Overall, this study elucidated the functional role of NUBP2 in CRC progression both in vitro and in vivo, providing insights into the molecular mechanisms underlying CRC and potential implications for targeted therapeutic strategies.

Re-injection off-axis integrated cavity output spectroscopy for the simultaneous detection of N2O, H2O and CO with a mid-infrared QCL laser.

Off-axis integrated cavity output spectroscopy (OA-ICOS) has attracted much interest because it potentially allows highly sensitive field measurements with robust optical alignment. In this paper, a novel instrument that employs a high-finesse optical cavity as an absorption cell has been developed for sensitive measurements of multi-component gases N2O, H2O and CO in the atmosphere based on a mid-infrared quantum cascade laser (QCL) and OA-ICOS. In order to improve the energy utilization and increase the signal-to-noise ratio (SNR) of the signal, a new type of optical path structure of the laser re-injection method is adopted. Furthermore, the system performance can be effectively improved by using a new intervention method of injecting radio frequency (RF) white noise into a laser driver to suppress cavity mode noise and combining the wavelength modulation method (WMS). We compared the sensitivity of the second harmonic signal demodulation between the re-injection method and the standard OA-ICOS, and the SNR increased by 2.68 times compared to the latter. Analysis of the spectral measurements with Allan variance indicates that within an integration time of 1 s, the measurement accuracy of N2O, H2O, and CO is 6.71 ppb, 13.945 ppm, and 1.81 ppb, respectively, and within an integration time of 820 s, the measurement accuracy of N2O, H2O, and CO can be further improved to 1.26 ppb, 2.089 ppm, and 172 ppt, respectively. Our approach represents an underlying analytical method that provides guidelines for monitoring of representative gases in the atmosphere, industrial processes, emergency safety, etc.

Unveiling the repressive mechanism of a PPS-like regulator (PspR) in polyhydroxyalkanoates biosynthesis network.

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a type of polyhydroxyalkanoates (PHA) that exhibits numerous outstanding properties and is naturally synthesized and elaborately regulated in various microorganisms. However, the regulatory mechanism involving the specific regulator PhaR in Haloferax mediterranei, a major PHBV production model among Haloarchaea, is not well understood. In our previous study, we showed that deletion of the phosphoenolpyruvate (PEP) synthetase-like (pps-like) gene activates the cryptic phaC genes in H. mediterranei, resulting in enhanced PHBV accumulation. In this study, we demonstrated the specific function of the PPS-like protein as a negative regulator of phaR gene expression and PHBV synthesis. Chromatin immunoprecipitation (ChIP), in situ fluorescence reporting system, and in vitro electrophoretic mobility shift assay (EMSA) showed that the PPS-like protein can bind to the promoter region of phaRP. Computational modeling revealed a high structural similarity between the rifampin phosphotransferase (RPH) protein and the PPS-like protein, which has a conserved ATP-binding domain, a His domain, and a predicted DNA-binding domain. Key residues within this unique DNA-binding domain were subsequently validated through point mutation and functional evaluations. Based on these findings, we concluded that PPS-like protein, which we now renamed as PspR, has evolved into a repressor capable of regulating the key regulator PhaR, and thereby modulating PHBV synthesis. This regulatory network (PspR-PhaR) for PHA biosynthesis is likely widespread among haloarchaea, providing a novel approach to manipulate haloarchaea as a production platform for high-yielding PHA. KEY POINTS: • The repressive mechanism of a novel inhibitor PspR in the PHBV biosynthesis was demonstrated • PspR is widespread among the PHA accumulating haloarchaea • It is the first report of functional conversion from an enzyme to a trans-acting regulator in haloarchaea.

Fractionated plasma separation and adsorption integrated with continuous veno-venous hemofiltration in patients with acute liver failure: A single center experience from China.

OBJECTIVE: To evaluate the clinical efficacy and safety of fractionated plasma separation and adsorption integrated with continuous veno-venous hemofiltration (FPSA-CVVH) treatment in patients with acute liver failure (ALF). METHODS: In this retrospective study, we enrolled patients with ALF (serum total bilirubin >10 mg/dL or Model for End-Stage Liver Disease [MELD] Score >18) hospitalized between August 2017 and August 2022. All patients had at least two sessions of FPSA-CVVH. The primary measure of treatment efficacy was the reduction ratios (RRs) of bilirubin after each session of FPSA-CVVH. RESULTS: Seventy-eight patients with ALF were enrolled. The MELD score at baseline was 22.9 ± 7.5. The mean total bilirubin was 22.05 ± 5.94 mg/dL, direct bilirubin was 16.33 ± 4.60 mg/dL and indirect bilirubin was 3.43 ± 1.60 mg/dL. One hundred and eighty seven sessions of FPSA-CVVH treatment lasting 8 hours each were performed. After a single session, serum total bilirubin, direct bilirubin and indirect bilirubin were significantly decreased. RRs were 52.0% ± 7.6% for total bilirubin, 59.4% ± 13.0% for direct bilirubin and 36.9% ± 15.4% for indirect bilirubin. Twenty nine patients (37.2%) survived and were discharged from the hospital, 12 of them recovered their liver function while the remaining 17 patients needed intermittent artificial liver support therapy. CONCLUSION: FPSA-CVVH therapy is an effective artificial liver support therapy in patients with ALF. It may be considered as a "bridge technique" to the recovery of liver function in critical ill patients with ALF.

Fractionated plasma separation and adsorption integrated with continuous veno-venous hemofiltration in patients with acute bipyridine herbicide poisoning.

OBJECTIVE: To evaluate the clinical efficacy and safety of fractionated plasma separation and adsorption combined with continuous veno-venous hemofiltration (FPSA-CVVH) treatment in patients with acute bipyridine herbicide poisoning. METHODS: A retrospective analysis of 18 patients with acute bipyridine herbicide poisoning was conducted, of which 9 patients were poisoned by diquat and 9 patients by paraquat. All patients underwent FPSA-CVVH treatment. The serum cytokine levels in pesticide-poisoned patients were assessed. The efficacy of FPSA-CVVH in eliminating cytokines, the 90-d survival rate of poisoned patients, and adverse reactions to the treatment were observed. RESULTS: Fourteen patients (77.8%) had acute kidney injuries and 10 (55.6%) had acute liver injuries. The serum cytokine levels of high mobility group protein B-1 (HMGB-1), interleukin-6 (IL-6), IL-8, interferon-inducible protein-10 (IP-10), monocyte chemotactic protein-1 (MCP-1), and macrophage inflammatory protein-1ß (MIP-1ß) were significantly elevated. A total of 41 FPSA-CVVH treatment sessions were administered. After a single 8-h FPSA-CVVH treatment, the decreases in HMGB-1, IL-6, IL-8, IP-10, MCP-1, and MIP-1ß were 66.0%, 63.5%, 73.3%, 63.7%, 53.9%, and 54.1%, respectively. During FPSA-CVVH treatment, one patient required a filter change due to coagulation in the plasma component separator, and one experienced a bleeding adverse reaction. The 90-d patient survival rate was 50%, with 4 patients with diquat poisoning and 5 patients with paraquat poisoning, and both liver and kidney functions were restored to normal. CONCLUSION: Cytokine storms may play a significant role in the progression of multiorgan dysfunction in patients with acute bipyridine herbicide poisoning. FPSA-CVVH can effectively reduce cytokine levels, increase the survival rate of patients with acute bipyridine herbicide poisoning, and decrease the incidence of adverse events.

Ultra-wideband flexible radar-infrared bi-stealth absorber based on a patterned graphene.

In this work, an ultra-wideband flexible radar absorber with low infrared emissivity for a radar-infrared bi-stealth application utilizing multilayer patterned graphene is proposed. The proposed absorber consists of three layers of graphene films with different patterns, flexible substrates, lightweight foam, and a ground layer. The flexible graphene films, rather than the conventional lumped resistors, are adopted as omnidirectional resistors to achieve dual polarization and flexibility. On the top of the absorber, an infrared shielding layer (IRSL) consists of patterned Indium tin oxide (ITO) separated by a thin foam layer. Due to the low-pass characteristics and the high filling ratio of the top ITO layer, the infrared emissivity of the whole structure is reduced effectively while the radar absorption property is slightly affected. As a result, the 90% absorption band is from 1.96 GHz to 20.72 GHz (fractional bandwidth 165.4%), with a low infrared emissivity of about 0.35. Besides, a miniaturized unit is achieved with the period of 0.079 λl at the lowest absorption frequency, and the oblique angle incidence response is up to 45° for TE mode and 60° for TM mode. A plane and a bending prototype are fabricated and measured, respectively. The screen-printing technology is adopted to print the graphene resistive films, and the measurement results agree well with the simulation.

Method of adaptive wide dynamic range gas concentration detection based on optimized direct absorption spectroscopy.

For wide dynamic range gas concentration detection based on tunable diode laser absorption spectroscopy (TDLAS), direct absorption spectroscopy (DAS) and wavelength modulation spectroscopy (WMS) are usually used in combination. However, in some application scenarios such as high-speed flow field detection, natural gas leakage, or industrial production, the requirements of wide-range, fast response and calibration-free must be met. Taking applicability and cost of TDALS-based sensor into consideration, a method of optimized direct absorption spectroscopy (ODAS) based on signal correlation and spectral reconstruction is developed in this paper. This method can achieve adaptive selection of the optimal benchmark spectrum for spectral reconstruction. Moreover, methane (CH4) is taken as an example to carry out the experimental verification. Experimental results proved that the method satisfies wide dynamic range detection of more than 4 orders of magnitude. It is worth noting that when measuring large absorbance with concentration of 75 × 104 ppm with DAS and ODAS method, respectively, the maximum value of residual is reduced from 3.43 to 0.07. Furthermore, whether measuring gas of small or large absorbance with different concentrations, which vary from 100 ppm to 75 × 104 ppm, the correlation coefficient between standard concentrations and inverted concentrations is 0.997, showing the linear consistency of the method in wide dynamic range. In addition, the absolute error is 1.81 × 104 ppm when measuring large absorbance of 75 × 104 ppm. It greatly improves the accuracy and reliability with the new method. In summary, the ODAS method can not only fulfill the measurement of gas concentration in wide range, but also further expand the application prospects of TDLAS.

Presenting limb severity is associated with long-term outcomes after infrainguinal revascularization for chronic limb-threatening ischemia.

OBJECTIVE: The SVS Wound, Ischemia, foot Infection (WIfI) limb staging system was established to estimate risk of major amputation in chronic limb-threatening ischemia (CLTI) and better stratify outcomes comparisons. There is little data on treatment outcomes beyond 1 year based on presenting WIfI stage. METHODS: This is a single-institution retrospective study of 413 patients who underwent infrainguinal revascularization for CLTI (2011-2021) with data available for WIfI staging. Patient characteristics and outcomes were gathered from the electronic medical record. Data were analyzed based on presenting WIfI stage and initial treatment received at our center. RESULTS: Presenting WIfI stages were 1 to 2 (23%), 3 (27%), and 4 (50%). Index revascularization approach was endoluminal (59%), autogenous vein bypass (29%), or non-autogenous bypass (13%). Operative mortality within 30 days was 2.9% and was not associated with WIfI stage or revascularization approach. Median limb follow-up time was 502 days (interquartile range [IQR], 112-1256 days), and median survival follow-up time was 932 days (IQR, 343-1770 days). Major amputation or death occurred in 19% and 46% of patients at median times of 119 days (IQR, 28-314 days) and 739 days (IQR, 204-1475 days), respectively. WIfI stage was independently associated with major amputation (P = .001), as was initial revascularization approach (P = .01). In a Cox proportional hazards model, factors independently associated with major amputation were male sex (hazard ratio [HR], 1.4; 95% confidence interval [CI], 1.04-2.0; P = .03), diabetes (HR, 1.8; 95% CI, 1.3-2.5; P = .001), WIfI stage 4 (HR, 2.3; 95% CI, 1.5-3.5; P < .001), and non-autogenous bypass (HR, 2.9; 95% CI, 2.1-4.2; P < .001). In a Cox proportional hazards model for mortality, independently associated factors were age (HR, 1.04; 95% CI, 1.02-1.05; P < .001), end-stage renal disease (HR, 2.8; 95% CI, 1.9-4.0; P < .001), congestive heart failure (HR, 1.9; 95% CI, 1.4-2.5; P < .001), chronic obstructive pulmonary disease (HR, 1.5; 95% CI, 1.1-2.1; P = .02), and WIfI stage 4 (HR, 1.6; 95% CI, 1.04-2.2; P = .03). Among those presenting with WIfI stage 4 limbs, Kaplan-Meier estimated rates of freedom from major amputation or death at 2 years were 71% ± 3.7% and 68% ± 3.5%, respectively. In an inverse propensity weighted Cox proportional hazards model, non-white race (HR, 1.5; 95% CI, 1.01-2.2; P = .047), diabetes (HR, 2.0; 95% CI, 1.2-3.3; P = .008), Global Anatomic Staging System infrapopliteal grade (HR, 1.2; 95% CI, 1.05-1.3; P = .005), non-autogenous bypass (HR, 3.2; 95% CI, 1.9-5.3; P < .001), and endoluminal revascularization (HR, 2.6; 95% CI, 1.6-4.3; P < .001) were independently associated with major amputation in the WIfI stage 4 subgroup. CONCLUSIONS: Presenting WIfI stage is strongly associated with long-term risks of major amputation and death following infrainguinal revascularization for CLTI and should be used to stratify outcomes comparisons. Effective revascularization is critical in WIfI stage 4 disease, and autogenous vein bypass provides durable long-term limb preservation.

Subgroup-specific gene expression profiles and mixed epistasis in chronic lymphocytic leukemia.

Understanding the molecular and phenotypic heterogeneity of cancer is a prerequisite for effective treatment. For chronic lymphocytic leukemia (CLL), recurrent genetic driver events have been extensively cataloged, but this does not suffice to explain the disease's diverse course. Here, we performed RNA sequencing on 184 CLL patient samples. Unsupervised analysis revealed two major, orthogonal axes of gene expression variation: the first one represented the mutational status of the immunoglobulin heavy variable (IGHV) genes, and concomitantly, the three-group stratification of CLL by global DNA methylation. The second axis aligned with trisomy 12 status and affected chemokine, MAPK and mTOR signaling. We discovered non-additive effects (epistasis) of IGHV mutation status and trisomy 12 on multiple phenotypes, including the expression of 893 genes. Multiple types of epistasis were observed, including synergy, buffering, suppression and inversion, suggesting that molecular understanding of disease heterogeneity requires studying such genetic events not only individually but in combination. We detected strong differentially expressed gene signatures associated with major gene mutations and copy number aberrations including SF3B1, BRAF and TP53, as well as del(17)(p13), del(13)(q14) and del(11)(q22.3) beyond dosage effect. Our study reveals previously underappreciated gene expression signatures for the major molecular subtypes in CLL and the presence of epistasis between them.

Clinical efficacy of centrifugal-membranous hybrid double filtration plasmapheresis and membranous double filtration plasmapheresis on severe lupus nephritis.

OBJECTIVE: The study delves into the clinical efficacy and safety of centrifugal-membranous hybrid double filtration plasmapheresis (C/M hybrid DFPP) on severe lupus nephritis (LN) by comparing it with membranous DFPP (M DFPP). METHODS: A retrospective cohort study was conducted in 70 patients who were diagnosed with severe LN and had received DFPP treatment. RESULTS: A total of 181 DFPPs were performed, including 133 C/M hybrid DFPPs (51 patients) and 48 M DFPPs (19 patients).The ANA, A-dsDNA titer, quantitative urinary protein, and serum creatinine decreased significantly and hemoglobin increased significantly after the DFPP treatment and at third month after treatment. Two patients in the M DFPP group developed bleeding complications, and four patients in the C/M hybrid DFPP group developed perioral numbness. CONCLUSION: Although there was no significant difference in clinical efficacy between C/M hybrid DFPP and M DFPP on severe LN, the risk of bleeding complications was significantly lower in the C/M hybrid DFPP group.

Customizing cancer treatment at the nanoscale: a focus on anaplastic thyroid cancer therapy.

Anaplastic thyroid cancer (ATC) is a rare but highly aggressive kind of thyroid cancer. Various therapeutic methods have been considered for the treatment of ATC, but its prognosis remains poor. With the advent of the nanomedicine era, the use of nanotechnology has been introduced in the treatment of various cancers and has shown great potential and broad prospects in ATC treatment. The current review meticulously describes and summarizes the research progress of various nanomedicine-based therapeutic methods of ATC, including chemotherapy, differentiation therapy, radioiodine therapy, gene therapy, targeted therapy, photothermal therapy, and combination therapy. Furthermore, potential future challenges and opportunities for the currently developed nanomedicines for ATC treatment are discussed. As far as we know, there are few reviews focusing on the nanomedicine of ATC therapy, and it is believed that this review will generate widespread interest from researchers in a variety of fields to further expedite preclinical research and clinical translation of ATC nanomedicines.

Association of Intraoperative and Perioperative Transfusions with Postoperative Cardiovascular Events and Mortality After Infrainguinal Revascularization.

BACKGROUND: Patients undergoing open or endovascular infrainguinal revascularization are at an elevated risk for postoperative cardiovascular complications due to high rates of comorbidities and the physiologic stress of surgery. Transfusions are known to be associated with adverse events but knowledge of specific risks associated with transfusion timing, product type, and long-term outcomes while accounting for preoperative cardiovascular risk factors is not well understood in this population. This study aimed to characterize the association of intraoperative and perioperative transfusion, anemia, and cardiovascular risk factors with cardiovascular events and mortality in patients undergoing infrainguinal revascularization. METHODS: A single-center retrospective study was performed on 564 infrainguinal revascularization procedures, including both open (n = 250) and endovascular (n = 314) approaches (2016-2020). Comprehensive clinical data were collected including patient demographics, cardiovascular risk factors, preoperative hemoglobin, and detailed transfusion data. Multivariable logistic regression tested the association of transfusions with composite 30-day outcomes of cardiac complications (postoperative myocardial infarction [postop-MI], congestive heart failure, or dysrhythmia) and with major adverse cardiovascular events (MACE-postop-MI or death). Kaplan-Meier analysis and Cox proportional hazard modeling examined the association of transfusions, anemia, and cardiovascular risk factors with mortality up to 1 year. RESULTS: Intraoperative transfusion was performed in 15% of cases and 13% underwent transfusion in the early postoperative period. Intraoperative transfusion was associated with higher Revised Cardiac Risk Index (RCRI), lower preoperative hemoglobin, increased blood loss, and open procedures (all P < 0.05). Within each RCRI score, intraoperative transfusion was associated with 2-4-fold increased MACE at 30 days. Intraoperative packed red blood cells transfusion and early postoperative packed red blood cells transfusion was associated with more than 2-fold adjusted odds of any cardiovascular complication and intraoperative transfusion was also associated with MACE (all P < 0.05). Intraoperative transfusion was associated with mortality at 1 year on unadjusted analysis, but after adjustment for RCRI, age, and preoperative hemoglobin, only RCRI scores of 2 and 3+ and preoperatively hemoglobin remained significant risk factors for mortality. CONCLUSIONS: Intraoperative and early perioperative transfusions are strongly associated with worse cardiovascular outcomes after infrainguinal revascularization. These findings may have a prognostic value for further risk stratifying patients perioperatively at a high risk for complications. However, prospective studies are needed to elucidate whether optimizing transfusion strategies mitigates these risks.

Vibration Reduction and Explosion Control Investigation for an Ultra-Shallow Buried Tunnel under Crossing Buildings Based on HHT Analysis.

With the rapid development of underground space utilization, the excavation of new tunnels with ultra-shallow under crossing buildings using the drilling and blasting method is gradually increasing. The blasting vibration will undoubtedly affect the surrounding buildings. Reducing the impact of blasting vibration on ground buildings has become an important technical challenge faced by tunnel blasting technicians. The inlet end of the Xi'an-Chengdu High-Speed Railway Xiannvyan Tunnel passes below a village through an ultra-shallow buried section; as a result, blasting vibration control is a major concern. A design scheme for a 0.6 m footage in tunnel was proposed and verified through field tests. A 0.8 m footage scheme and 1.8 m footage millisecond interference vibration reduction scheme were proposed, respectively. Based on the HHT analysis, by comparing the surface vibration velocities and instantaneous energy obtained from the millisecond delay detonation of cutting holes and the detonation of different charging schemes, we found that the free surface, mass of single dynamite charges, and tunnel burial depth had significant influences on the surface vibration.

Development of a Rapid Measurement Method for Analysis of the NOx Conversion Process Based on Quantum Cascade Laser Absorption Spectroscopy.

In this study, a method for double-beam quantum cascade laser absorption spectroscopy (DB-QCLAS) was developed. Two mid-infrared distributed feedback quantum cascade laser beams were coupled in an optical cavity for the monitoring of NO and NO2 (NO at 5.26 µm; NO2 at 6.13 µm). Appropriate lines in the absorption spectra were selected, and the influence of common gases in the atmosphere, such as H2O and CO2, was avoided. By analyzing the spectral lines under different pressure conditions, the appropriate measurement pressure of 111 mbar was selected. Under this pressure, the interference between adjacent spectral lines could be effectively distinguished. The experimental results show that the standard deviations for NO and NO2 were 1.57 ppm and 2.67 ppm, respectively. Moreover, in order to improve the feasibility of this technology for detecting chemical reactions between NO and O2, the standard gases of NO and O2 were used to fill the cavity. A chemical reaction instantaneously began, and the concentrations of the two gases were immediately changed. Through this experiment, we hope to develop new ideas for the accurate and rapid analysis of the process of NOx conversion and to lay a foundation for a deeper understanding of the chemical changes in atmospheric environments.

Transcriptome Analysis Revealed the Dynamic and Rapid Transcriptional Reprogramming Involved in Cold Stress and Related Core Genes in the Rice Seedling Stage.

Cold damage is one of the most important environmental factors influencing crop growth, development, and production. In this study, we generated a pair of near-isogenic lines (NILs), Towada and ZL31, and Towada showed more cold sensitivity than ZL31 in the rice seedling stage. To explore the transcriptional regulation mechanism and the reason for phenotypic divergence of the two lines in response to cold stress, an in-depth comparative transcriptome study under cold stress was carried out. Our analysis uncovered that rapid and high-amplitude transcriptional reprogramming occurred in the early stage of cold treatment. GO enrichment and KEGG pathway analysis indicated that genes of the response to stress, environmental adaptation, signal transduction, metabolism, photosynthesis, and the MAPK signaling pathway might form the main part of the engine for transcriptional reprogramming in response to cold stress. Furthermore, we identified four core genes, OsWRKY24, OsCAT2, OsJAZ9, and OsRR6, that were potential candidates affecting the cold sensitivity of Towada and ZL31. Genome re-sequencing analysis between the two lines revealed that only OsWRKY24 contained sequence variations which may change its transcript abundance. Our study not only provides novel insights into the cold-related transcriptional reprogramming process, but also highlights the potential candidates involved in cold stress.

A Peptide Derived from GAPDH Enhances Resistance to DNA Damage in Saccharomyces cerevisiae Cells.

Social behaviors do not exist only in higher organisms but are also present in microbes that interact for the common good. Here, we report that budding yeast cells interact with their neighboring cells after exposure to DNA damage. Yeast cells irradiated with DNA-damaging UV light secrete signal peptides that can increase the survival of yeast cells exposed to DNA-damaging stress. The secreted peptide is derived from glyceraldehyde-3-phosphate dehydrogenase (GAPDH), and it induced cell death of a fraction of yeast cells in the group. The data suggest that the GAPDH-derived peptide serves in budding yeast's social interaction in response to DNA-damaging stress. IMPORTANCE Many studies have shown that microorganisms, including bacteria and yeast, display increased tolerance to stress after exposure to the same stressor. However, the mechanism remains unknown. In this study, we report a striking finding that Saccharomyces cerevisiae cells respond to DNA damage by secreting a peptide that facilitates resistance to DNA-damaging stress. Although it has been shown that GAPDH possesses many key functions in cells aside from its well-established role in glycolysis, this study demonstrated that GAPDH is also involved in the social behaviors response to DNA-damaging stress. The study opens the gate to an interesting research field about microbial social activity for adaptation to a harsh environment.

Flexible frequency-selective rasorber based on metal-graphene hybrid metamaterial.

In this work, we demonstrate a flexible frequency-selective rasorber (FSR) with great angular stability and conformal superiority using metal-graphene hybrid metamaterial. The metamaterial is fabricated by filling the designed metal patterns with graphene-based ink. It can replace the traditional resistors to introduce loss for the absorption purpose. Therefore, the FSR does not need any lumped components soldered onto its surface, enabling a high flexibility and conformal capability. The metal-graphene FSR is fabricated and measured on flexible substrates that have a 60° angular stability and a 128° conformal angle. The simulations and experiments confirmed that the proposed metal-graphene FSR exhibits excellent angular stability and considerable flexibility, making it ideal for stealth systems.