Composition of DOM along the depth gradients in the paddy field treated with crop straw for 10 years.

Crop straw return is a widely used agricultural management practice. The addition of crop straw significantly alters the pool of dissolved organic matter (DOM) in agricultural soils and plays a pivotal role in the global carbon (C) cycle, which is sensitive to climate change. The DOM concentration and composition at different soil depths could regulate the turnover and further storage of organic C in terrestrial systems. However, it is still unclear how crop straw return influences the change in DOM composition in rice paddy soils. Therefore, a field experiment was conducted in which paddy soil was amended with crop straw for 10 years. Two crop straw-addition treatments [NPK with 50% crop straw (NPK+1/2S) and NPK with 100% crop straw (NPK + S)], a conventional mineral fertilization control (NPK) and a non-fertilized control were included. Topsoil (0-20 cm) and subsoil (20-40 cm) samples were collected to investigate the soil DOM concentration and compositional structure of the profile. Soil nutrients, iron (Fe) fraction, microbial biomass carbon (MBC), and concentration and optical properties (UV-Vis and fluorescence spectra) of soil DOM were determined. Here, we found that the DOM in the topsoil was more humified than that in the subsoil. The addition of crop straw further decreased the humidification degree of DOM in the subsoil. In crop straw-amended topsoil, microbial decomposition controlled the composition of DOM and induced the formation of aromatic DOM. In the straw-treated subsoil, selective adsorption by poorly crystalline Fe(oxyhydr)oxides and microbial decomposition controlled the composition of DOM. In particular, the formation of protein-like compounds could have played a significant role in the microbial degradation of DOM in the subsoil. Overall, this work conducted a case study within long-term agricultural management to understand the changes in DOM composition along the soil profile, which would be further helpful for evaluating C cycling in agricultural ecosystems.

𝛍m-resolution thickness distribution measurement of transparent glass films by using a multi-wavelength phase-shift extraction method in the large lateral shearing interferometer.

In this paper, a precise phase-shift extraction method was introduced for the first time to measure the thickness distribution of transparent glass films. A spatial light modulator modulated the phases of the incident laser in a large lateral shearing interferometer. The phase shifting caused by the thickness of the films can be extracted ranging from 0 to 2π, in a recursive way suitable for real-time implementation. Incident lasers with different wavelengths were utilized to measure the spatial distribution of the thickness of the films, and they can be larger than one wavelength of the incident light. Both artificial and experimental results have verified that the resolution of the thickness measurement reaches up to 1 𝛍m.

Safety and efficacy of remifentanil-propofol combination on "muscle relaxant-free" general anesthesia for therapeutic endoscopic retrograde cholangiopancreatography: a randomized controlled trial.

OBJECTIVE: To prospectively evaluate the safety and efficacy of a "muscle relaxant-free" general anesthesia using a combination of remifentanil and propofol, compared to propofol-based monitored anesthesia care and conventional general anesthesia during therapeutic endoscopic retrograde cholangiopancreatography (ERCP). METHODS: From September to December 2019, 360 patients scheduled for elective ERCP at the Endoscopy Center of the First Affiliated Hospital of Nanjing Medical University were randomly assigned to three different groups: Group MAC (propofol-based monitored anesthesia care, n=120), Group GA1 (general anesthesia with neuromuscular blocking agents, n=120), or Group GA2 (remifentanil-propofol combination-based muscle relaxant-free general anesthesia, n=120). RESULTS: The results showed that there was a significant difference in intraprocedural cardiopulmonary adverse events among the three groups (Group MAC, 37.5%; Group GA1, 19.2%; Group GA2, 17.5%; P < 0.001). Total time (from patient entry into the Endoscopy Center to departure) and room time (from patient entry into the endoscopy suit to departure) were shorter in Group GA2 and Group MAC compared to Group GA1 (P < 0.001). Additionally, endoscopist satisfaction levels were significantly higher in Group GA1 and Group GA2 compared to Group MAC (P < 0.001). CONCLUSION: The study found that administering propofol-remifentanil combination for "muscle relaxant-free" general anesthesia during therapeutic ERCP was safe and effective. This approach offered greater safety and endoscopist satisfaction than propofol-based monitored anesthesia care, as well as shorter total time and room time than conventional general anesthesia.

Specialized morphology and material properties make a honey bee tongue both extendible and structurally stable.

The honey bee, Apis mellifera ligustica, uses the specialized tongue structured by ∼120 segmental units, coated by bushy hairs, to dip varying concentration nectar flexibly at small scales. While dipping, the segmental units elongate by 20%, coordinated with rhythmical erection of hairs, the pattern of which is demonstrated to be capable of both increasing nectar intake rate and saving energy. The compliance in the segmental units allows extension of the tongue, which however, challenges the structural stability while traveling through the viscous fluid. In this combined experimental and theoretical investigation, we apply scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM), micro-computed tomography scanning (micro-CT), atomic force microscopy (AFM), and mechanical models to reveal the structural and material specializations in a bee tongue for meeting the functionally contradictive demands. We find that each segmental unit is a complex structure, which is composed of an intersegmental membrane (ISM) and a ring-like hair base (RHB), with spatially distributed discrete changes in material properties. The combination of these two components makes the tongue multifunctional, in which the ISMs characterized by resilin-rich material make the segmental units compliant, while the RHBs with rigid sclerotized material provide stable supporting for hairs. Our study may enlighten deployable mechanisms with correlative functional components, especially the microscopic mechanisms applied in viscous fluid tranport. STATEMENT OF SIGNIFICANCE: The honey bee tongue is a versatile tool that extends to probe into varying-shaped corollas, retracting with 3,000 glossal hairs staying erected to load nectar. The combined requirement of both deformability and structural stability imposes opposing demands on structural stiffness. Here we show that glossal hairs are supported by rigid continuum ring-like hair bases, embedded in the elastic resilient intersegmental membrane, making the whole tongue both flexible and rigid at the same time. Our findings extend our understanding of relationship between morphology, material composition and biomechanics of dynamic biological surfaces, which may inspire design paradigms of multifunctional deployable mechanisms coordinating deformability and structural stability.

[Impregnate occasion for male renal transplant recipients].

OBJECTIVE: To explore the impregnate occasion for male renal transplant recipients. METHODS: Twenty-six male renal transplant recipients were divided into 3 groups according to the post-transplantation time and the administered dose of Cyclosporine A: 7 in Group A (less than 6 months after renal transplantation and at the dose of 4.1-6 mg/[kg x d]), 11 in Group B (6-24 months and 2.1-4 mg/[kg x d]) and 8 in Group C (longer than 24 months and 1.3-2 mg/[kg x d]). The semen of the patients were detected and compared with those of 12 normal volunteers. RESULTS: Statistically significant differences were observed in sperm motility and sperm head deformity between Group A and C (P < 0.05), but not in pH value and sperm volume, vitality and concentration among the 3 groups (P > 0.05). CONCLUSION: For male renal transplant recipients, 2 years or longer after the transplantation is the most suitable time for impregnation.

Characterization of clinical Vibrio parahaemolyticus strains in Zhoushan, China, from 2013 to 2014.

Vibrio parahaemolyticus is recognized as major cause of foodborne illness of global public health concern. This study collected 107 strains of V. parahaemolyticus during active surveillance of diarrheal diseases in hospitals in Zhoushan during 2013 to 2014 and investigated their serotypes, virulence genes (tdh, trh, and orf8), antimicrobial resistance, and genotypes. The dominant serotypes of the 107 clinical strains were O3:K6, O4:K8, and O4:KUT with 87.9% and 3.7% of the strains carrying the virulence genes tdh and trh, respectively. Molecular typing by pulsed-field gel electrophoresis indicated divergence among the clinical strains. Most isolates were sensitive to the common antimicrobial agents used against the Vibrio species except ampicillin. We conclude that continuous surveillance of V. parahaemolyticus in diarrhea patients is a public health priority and is useful for conducting risk assessment of foodborne illnesses caused by V. parahaemolyticus.

Identification of Pseudomonas syringae type III effectors that can suppress programmed cell death in plants and yeast.

The Pseudomonas syringae pv. tomato DC3000 type III secretion system (TTSS) is required for bacterial pathogenicity on plants and elicitation of the hypersensitive response (HR), a programmed cell death (PCD) that occurs on resistant plants. Cosmid pHIR11 enables non-pathogens to elicit an HR dependent upon the TTSS and the effector HopPsyA. We used pHIR11 to determine that effectors HopPtoE, avirulence AvrPphEPto, AvrPpiB1Pto, AvrPtoB, and HopPtoF could suppress a HopPsyA-dependent HR on tobacco and Arabidopsis. Mixed inoculum and Agrobacterium-mediated transient expression experiments confirmed that suppressor action occurred within plant cells. These suppressors, with the exception of AvrPpiB1Pto, inhibited the expression of the tobacco pathogenesis-related (PR) gene PR1a. DC3000 suppressor mutants elicited an enhanced HR consistent with these mutants lacking an HR suppressor. Additionally, HopPtoG was identified as a suppressor on the basis of an enhanced HR produced by a hopPtoG mutant. Remarkably, these proteins functioned to inhibit the ability of the pro-apoptotic protein, Bax to induce PCD in plants and yeast, indicating that these effectors function as anti-PCD proteins in a trans-kingdom manner. The high proportion of effectors that suppress PCD suggests that suppressing plant immunity is one of the primary roles for DC3000 effectors and a central requirement for P. syringae pathogenesis.