The comparison of fluidized positioners and traditional gel pads for skin protection in neurosurgical patients undergoing lateral and prone positions: A retrospective analysis with propensity score matching method.

To compare fluidized positioners and gel pads for skin protection in neurosurgery patients placed in lateral and prone positions. It is one of the major challenges that operating room nurses face in protecting the skin during the long duration of neurosurgery. Currently, there are increasing tools available to protect the skin under pressure, and various tools practice well in the clinic. Fluidized positioners are newly emerging protective pads that have been clinically effective in protecting the skin, but no studies have compared them to previous pads. This is a retrospective cohort study. Data from 706 patients who underwent neurosurgery between January 2018 and December 2021 were systemically reviewed. Patients undergoing long-term neurosurgery in the neurosurgical lateral and prone positions were divided into two groups: fluidized positioners or gel pads. Propensity score matching (PSM) was performed for group balance (1:1 ratio) using the following baseline characteristics: age, gender, ASA (American Society of Anesthesiologists) classification, duration of surgery, surgical position and underlying disease. The incidence of decubitus, and length of stay (LOS) in the hospital were compared between the two groups. The results were obtained for 394 patients in the fluidized positioner group with a 3.8% incidence of pressure ulcers and 312 patients in the gel pad group with an 8% incidence of pressure ulcers, which were unbalanced in terms of gender, ASA, hypertension and diabetes data. After a PSM, patients were compared in terms of pressure ulcer incidence (3.7% vs. 7.8%, p = 0.034) and LOS (22.35 vs. 25.65 days, p < 0.001). Fluidized positioners can effectively reduce the incidence of pressure injury in lateral and prone positions of neurosurgery. The results of this study may contribute to the development of policies to prevent the development of pressure ulcers during neurosurgical procedures.

Effects of rice husk powder and thermal hydrolysis on sludge characteristics.

To reduce the water content and improve the incineration characteristics of sludge, rice husk and thermal hydrolysis were employed in this study. Effects of rice husk and thermal hydrolysis on the characteristics of the sludge were investigated. The results showed that synergistic thermal hydrolysis with rice husk could effectively destroy sludge particles and release more bound water. For rice husk with a particle size of 50-mesh and an additional amount of rice husk at 1:0.2, the solid content of the sludge was reduced from 17.4 to 16.2%, and the sludge particle size was reduced by 6%. Filtration time and specific resistance to filtrate (SRF) were shortened by 88.9 and 98.7%, respectively. The organic matter content of the filtration cake increased by 14%, compared with the sludge treated by thermal hydrolysis without rice husk. Furthermore, it could be shown that the most optimal conditions were rice husk of particle size 50-mesh and an additional amount of rice husk at 1:0.2, which could lead to effective thermal hydrolysis and higher organic matter content of the filtration cake.

Improved opposition-based self-adaptive differential evolution algorithm for vibrational hybrid femtosecond/picosecond coherent anti-Stokes Raman scattering thermometry.

We propose an improved opposition-based self-adaptive differential evolution (IOSaDE) algorithm for multi-parameter optimization in vibrational hybrid femtosecond/picosecond coherent anti-Stokes Raman scattering (CARS) thermometry. This new algorithm self-adaptively combines the advantages of three mutation schemes and introduces two opposite population stages to avoid premature convergence. The probability of choosing each mutation scheme will be updated based on its previous performance after the first learning period. The IOSaDE method is compared with nine other traditional differential evolution (DE) methods in simulated spectra with different simulation parameters and experimental spectra at different probe time delays. In simulated spectra, both the average and standard deviation values of the final residuals from 20 consecutive trials using IOSaDE are more than two orders of magnitude smaller than those using other methods. Meanwhile, the fitting temperatures in simulated spectra using IOSaDE are all consistent with the target temperatures. In experimental spectra, the standard deviations of the fitting temperatures from 20 consecutive trials decrease more than four times by using IOSaDE, and the errors of the fitting temperatures also decrease more than 18%. The performance of the IOSaDE algorithm shows the ability to achieve accurate and stable temperature measurement in CARS thermometry and indicates the potential in applications where multiple parameters need to be considered.

Hybrid fs/ps vibrational coherent anti-Stokes Raman scattering for simultaneous gas-phase N2/O2/CO2 measurements.

Single-shot, 1-kHz measurements of temperatures and mole fraction ratios along with theoretical modeling for gas-phase N2, O2, and CO2 are demonstrated using hybrid femtosecond/picosecond (fs/ps) vibrational coherent anti-Stokes Raman scattering (CARS). The combination of broadband pump and Stokes pulses covers a spectral range over 1800cm-1 while the narrowband probe pulses generated from a quasi-common-path second harmonic bandwidth compressor (QCP-SHBC) resolves the molecular structures with a bandwidth of ∼7cm-1. Temperature results of 1700-2000 K in methane/air fuel-lean flames show state-of-the-art inaccuracies of less than ∼3% and precision less than 2%. Mole fraction ratios inaccuracy at room temperature is ∼5%, and precision at flame temperatures are 6%-8%.

Dual-wavelength wide area illumination Raman difference spectroscopy for remote detection of chemicals.

Remote Raman instruments have become powerful analytical tools in some special environments. However, ambient daylight is the main limitation in the data acquisition process. To suppress daylight background interference and obtain a high signal-to-background ratio (SBR), we develop a dual-wavelength wide area illumination Raman difference spectroscopy (WAIRDS) system for daytime remote detection. In the WAIRDS system, a wide area illumination scheme and shifted-excitation Raman difference spectroscopy method are used to improve the reliability of collected Raman spectra. Measurements of polystyrene indicate that the WAIRDS system can be operated to obtain background-free Raman spectra under different levels of daylight background interference. The remote results show that the improvement in SBR is about three- to fivefold, and the system can work at distances of up to 9.2 m on a sunny afternoon. Moreover, to be close to the actual detection, the system is used for mineral and explosive raw material detection during daytime measurement. Measurements show that the WAIRDS system will be a useful tool for many remote applications in the future.

Baseline correction method based on improved asymmetrically reweighted penalized least squares for the Raman spectrum.

We present a baseline correction method based on improved asymmetrically reweighted penalized least squares (IarPLS) for the Raman spectrum. This method utilizes a new S-type function to reduce the risk of baseline overestimation and speed up the reweighting process. Simulated spectra with different levels of noise and measured spectra with strong fluorescence background from different samples are used to validate the performance of the proposed algorithm. Considering the drawbacks of the weighting rules for the asymmetrically reweighted penalized least squares (arPLS) method, we adapt an inverse square root unit (ISRU) function, which performs well in baseline correction. Compared with previous penalized least squares methods, such as asymmetric least squares, adaptive iteratively reweighted penalized least squares, and arPLS, experiments with the simulated Raman spectra have confirmed that the proposed method yields better outcomes. Experiments with the measured Raman spectra show that the IarPLS method can improve real Raman spectra within 20 ms. The results show that the proposed method can be successfully applied to the practical Raman spectrum as a strong basis for quantitative analysis.

Algicidal activity against Skeletonema costatum by marine bacteria isolated from a high frequency harmful algal blooms area in southern Chinese coast.

Four marine bacterial strains P1, P5, N5 and N21 were isolated from the surface water and sediment of Mirs Bay in southern Chinese coast using the liquid infection method with 48-well plates. These bacteria were all shown to have algicidal activities against Skeletonema costatum. Based on morphological observations, biochemical tests and homology comparisons by 16S rDNA sequences, the isolated strains P1, P5, N5 and N21 were identified as Halobacillus sp., Muricauda sp., Kangiella sp. and Roseivirga sp., respectively. Our results showed that bacterial strain P1 killed S. costatum by release of heat labile algicide, while strains P5, N5 and N21 killed them directly. The algicidal processes of four bacterial strains were different. Strains P1, N5 and N21 disrupted the chain structure and S. costatum appeared as single cells, in which the cellular components were aggregated and the individual cells were inflated and finally lysed, while strain P5 decomposed the algal chains directly. We also showed that the algicidal activities of the bacterial strains were concentration-dependent. More specifically, 10 % (v/v) of bacteria in algae showed the strongest algicidal activities, as all S. costatum cells were killed by strains N5 and N21 within 72 h and by strains P1 and P5 within 96 h. 5 % of bacteria in algae also showed significant algicidal activities, as all S. costatum were killed by strains N5, P5 and N21 within 72, 96 and 120 h, respectively, whereas at this concentration, only 73.4 % of S. costatum cells exposed to strain P1 were killed within 120 h. At the concentration of 1 % bacteria in algae, the number of S. costatum cells continued to increase and the growth rate of algae upon exposure to strain N5 was significantly inhibited.

Finite Element Analysis of Bonding Property and Flexural Strength of WUHPC-NC Gradient Concrete.

Ultra-high-performance concrete (UHPC) has greater mechanical and durability performance than normal concrete (NC). Using a limited dosage of UHPC on the external surface of NC to form a gradient structure could significantly improve the strength and corrosion resistance of the concrete structure and avoid the problems caused by bulk UHPC. In this work, white ultra-high-performance concrete (WUHPC) was selected as an external protection layer for normal concrete to construct the gradient structure. WUHPC of different strengths were prepared, and 27 gradient WUHPC-NC specimens with different WUHPC strengths and interval times of 0, 10, and 20 h were tested using splitting tensile strength to reveal the bonding properties. Fifteen prism gradient specimens with the size of 100 × 100 × 400 mm and a WUHPC ratio of 1:1, 1:3, and 1:4 were tested using the four-pointed bending method to study the bending performance of the gradient concrete with different WUHPC thicknesses. Finite element models with different WUHPC thicknesses were also built to simulate the cracking behaviors. The results showed that the bonding properties of WUHPC-NC were stronger with less interval time and reached the maximum of 1.5 MPa when the interval was 0 h. Moreover, the bond strength first increased and then decreased with the decline in the strength gap between WUHPC and NC. When the thickness ratios of WUHPC to NC were 1:4, 1:3, and 1:1, the flexural strength of the gradient concrete improved by 89.82%, 78.80%, and 83.31%, respectively. The major cracks rapidly propagated from the 2 cm position to the bottom of the mid-span, and the thickness of 1:4 was the most efficient design. The results simulated by finite element analysis also proved that the elastic strain at the crack propagating point was the minimum and was easier to crack. The simulated results were in good accordance with the experimental phenomenon.

Preparation and Color Performance of White Ultra-High-Performance Concrete with Large Fraction of Quaternary Binders.

White ultra-high-performance concrete (WUHPC) performed outstanding mechanical, durability, and aesthetical properties, which was preferred in infrastructure to avoid the secondary painting, decrease the maintenance, and prolong the service life. Supplementary cementitious materials (SCMs) were often used in WUHPC to reduce the environment impacts and material costs. In this study, limestone powder (LP), metakaolin (MK), and silica fume (SF) were used as SCMs to largely substitute white Portland cement (WPC) to prepare WUHPC, the effects of substituted ratio on flowability, strength, and whiteness were studied, and the hydration products were also analyzed by quantitative-XRD method and SEM. The whiteness was calculated in chromatic space CIELAB by measuring tristimulus values of L, a*, and b*, and the controlled factor on whiteness was also investigated. As the results, the WUHPC with compressive strength exceeded 150 MPa and whiteness over 90 was prepared with WPC substitution of 35~65%. The SF improved the flowability and strength about 10% due to its filling and ball effect, while the irregular particle sharp and non-uniform size distribution of MK caused the reversed development. The increased dosage of raw materials with higher L value, such as LP and MK, made the WUHPC whiter. The hydration products with varied SCMs ratio were in the same category by different content. It was supposed that CaCO3 and C-S-H gel in hydration products caused higher whiteness, while C3S, CaMg(CO3)2, and SiO2 were against the whiteness. The results proved that with a large fraction of SCMs, the WUHPC with high strength and good appearance were prepared, and the whiteness of WUHPC were both controlled by the raw materials and the content of hydration products.

The seamount effect on phytoplankton in the tropical western Pacific.

The tropical western Pacific, one of the most oligotrophic seas on Earth, has a large number of seamounts. In this sea, we hypothesize that although the presence of shallow seamounts can enhance phytoplankton biomass, they do not alter the phytoplankton community composition. The concentration and distribution of size-fractionated chlorophyll a (Chl a) on the C4 Seamount were measured, and the phytoplankton community was analyzed based on photosynthetic pigments. The results showed that the deep chlorophyll maximum (DCM) was located between 100 and 150 m and that picophytoplankton such as prochlorophytes and cyanobacteria (mainly Synechococcus) were the dominant groups, contributing approximately 85% of the Chl a. The integrated Chl a concentration above the seamount was significantly higher than that off the seamount, and most communities were enhanced near the peak. The physical, chemical, and biological coupling processes of the C4 Seamount support the classic hypothesis of the seamount effect. However, the relative contributions of different phytoplankton groups to Chl a were not significantly different between stations above and off the seamount, and the analysis of similarities among results also indicated that the community composition on the C4 Seamount did not differ significantly from that off the seamount. In addition, size-fractionated Chl a data from two nearby shallow seamounts also supported our hypothesis. More studies on the ecology of seamounts in the tropical western Pacific are required to further confirm and refine these results.

Data on microplastics in the digestive tracts of 19 fish species from the Yellow Sea, China.

Microplastics (MPs) are the predominant form of marine plastic debris, and small enough to be ingested by marine organisms. Fish inhabiting coastal environments are susceptible to the ingestion of MPs. Presented data include the information of MPs level in the digestive tracts of 19 fish species which were caught from the Yellow Sea (31°28'52.380"∼38°49'15.540″ N, 120°42'36.840"∼124°49'06.180″E). For discussion and interpretation of the presented data, refer to the research article entitled "Characteristics and retention of microplastics in the digestive tracts of fish from the Yellow Sea" [1].

Characteristics and retention of microplastics in the digestive tracts of fish from the Yellow Sea.

Microplastics (MPs) are a major global issue in the marine environment, and fish inhabiting coastal environments are susceptible to the ingestion of MPs. Knowledge regarding MPs in fish along the coast of China is very limited. In this study, the characteristics and retention of MPs in 19 fish species in the Yellow Sea were systematically studied. MPs were detected in all of the fish species sampled. Overall, 34% (444/1320) of fish retained plastic, and 552 pieces of plastic were removed from these fish, among which 546 pieces (99%) were microplastics (i.e., <5 mm). Three MP types were found: fibers, pellets, and fragments, which accounted for 67%, 22%, and 11% of the total, respectively. MP length ranged from 16 to 4740 µm, with an average of 941 ±â€¯43 µm. The average lengths of the fibers, pellets, and fragments were 1233 ±â€¯57 µm, 263 ±â€¯24 µm, and 503 ±â€¯91 µm, respectively, and MP length was positively correlated with fish length. Fourteen polymers were detected, with organic oxidation polymers (40%) being most abundant, followed by polyethylene (22%) and polyamide (11%). The retention of MPs in fish was affected by sampling areas and fish weight. Fish collected from the area adjacent to the Bohai Sea and the Yangtze River Estuary were found to possess higher levels of MPs than those collected from the center of the Yellow Sea. The average MP/fish for fish with plastic was negatively correlated with fish body weight. The retention of MPs may affect the quality and quantity of fishery resources in the Yellow Sea, especially the commercial fish. It is suggested that future studies be conducted to determine the ingestion rate, retention time, and egestion rate of MPs by fish to enable a rational risk assessment by combining the field results.

[Algicidal activity against red-tide algaes by marine bacterial strain N3 isolated from a HABs area, southern China].

A marine algicidal bacterium N3 was isolated from a HABs area in Mirs Bay, a subtropical bay, in southern China. Algicidal activity and algicidal mode against Phaeodactylum tricornutum, Scrippsiella trochoidea, Prorocentrum micans and Skeletonema costatum were observed by the liquid infection method. The results showed that there were no algicidal activities against P. tricornutum and S. costatum. However, when the bacterial volume fractions were 2% and 10% , S. trochoidea and P. micans could be killed, respectively. S. trochoidea cells which were exposed to strain N3 became irregular in shape and the cellular components lost their integrity and were decomposed. While, the P. micans cells became inflated and the cellular components aggregated, followed by cell lysis. Strain N3 killed S. trochoidea and P. micans directly, and the algicidal activities of the bacterial strain N3 was concentration-dependent. To S. trochoidea, 2% (V/V) of bacteria in algae showed the strongest algicidal activity, all of the S. trochoidea cells were killed within 120 h. But the growth rates of cells, in the 1% and 0. 1% treatment groups, were only slightly lower than that in the control group. In all treatment groups, the densities of strain N3 were in declining trends. While, to P. micans, 10% and 5% of bacteria in algae showed strong algicidal activities, 78% and 70% of the S. trochoidea were killed within 120 h, respectively. However, the number of S. trochoidea after exposure to 1% of bacterial cultures still increased up to 5 incubation days. And in the three treatment groups, the densities of strain N3 experienced a decrease process. The isolated strain N3 was identified as Bacillus sp. by morphological observation, physiological and biochemical characterization, and homology comparisons based on 16S rRNA sequences.