Effect of infill pattern of polylactide acid (PLA) 3D-printed integral sandwich panels under ballistic impact loading

This paper investigates the effect of the infill pattern of polylactide acid (PLA) 3D-printed sandwich panels under ballistic impact loading. Fused deposition modeling (FDM) technique is used to manufacture the PLA 3D-printed integral sandwich panels with four infill patterns: cubic, grid, gyroid, and honeycomb. The ballistic data acquisition system is collected the experimental results with three impact velocities: 109.65, 173.97, and 209.48 m/s. It was revealed that the 3D-printed sandwich panel with cubic infill pattern reached the highest maximum impact load than the other three infill patterns. Moreover, it was highlighted that the sandwich panel with cubic and gyroid infill patterns absorbed 1.41 and 1.15 J and provided better impact resistance characteristics. It is highlighted that the infill pattern plays a vital role in the impact resistance of 3D-printed sandwich structures. Furthermore, it is recommended the three-dimensional (3D) infill pattern, e.g., cubic, gyroid, 3D honeycomb, can provide better impact performance than the two-dimensional (2D) infill pattern

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals <1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Study of the B−→Λc+Λˉc−K−B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-} decay

The decay $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ is studied in proton-proton collisions at a center-of-mass energy of $\sqrt{s}=13$ TeV using data corresponding to an integrated luminosity of 5 $\mathrm{fb}^{-1}$ collected by the LHCb experiment. In the $\Lambda_{c}^+ K^{-}$ system, the $\Xi_{c}(2930)^{0}$ state observed at the BaBar and Belle experiments is resolved into two narrower states, $\Xi_{c}(2923)^{0}$ and $\Xi_{c}(2939)^{0}$, whose masses and widths are measured to be $$m(\Xi_{c}(2923)^{0}) = 2924.5 \pm 0.4 \pm 1.1 \,\mathrm{MeV}, \\ m(\Xi_{c}(2939)^{0}) = 2938.5 \pm 0.9 \pm 2.3 \,\mathrm{MeV}, \\ \Gamma(\Xi_{c}(2923)^{0}) = \phantom{000}4.8 \pm 0.9 \pm 1.5 \,\mathrm{MeV},\\ \Gamma(\Xi_{c}(2939)^{0}) = \phantom{00}11.0 \pm 1.9 \pm 7.5 \,\mathrm{MeV},$$ where the first uncertainties are statistical and the second systematic. The results are consistent with a previous LHCb measurement using a prompt $\Lambda_{c}^{+} K^{-}$ sample. Evidence of a new $\Xi_{c}(2880)^{0}$ state is found with a local significance of $3.8\,\sigma$, whose mass and width are measured to be $2881.8 \pm 3.1 \pm 8.5\,\mathrm{MeV}$ and $12.4 \pm 5.3 \pm 5.8 \,\mathrm{MeV}$, respectively. In addition, evidence of a new decay mode $\Xi_{c}(2790)^{0} \to \Lambda_{c}^{+} K^{-}$ is found with a significance of $3.7\,\sigma$. The relative branching fraction of $B^{-} \to \Lambda_{c}^{+} \bar{\Lambda}_{c}^{-} K^{-}$ with respect to the $B^{-} \to D^{+} D^{-} K^{-}$ decay is measured to be $2.36 \pm 0.11 \pm 0.22 \pm 0.25$, where the first uncertainty is statistical, the second systematic and the third originates from the branching fractions of charm hadron decays.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-028.html (LHCb public pages

Measurement of the ratios of branching fractions R(D∗)\mathcal{R}(D^{*}) and R(D0)\mathcal{R}(D^{0})

The ratios of branching fractions $\mathcal{R}(D^{*})\equiv\mathcal{B}(\bar{B}\to D^{*}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(\bar{B}\to D^{*}\mu^{-}\bar{\nu}_{\mu})$ and $\mathcal{R}(D^{0})\equiv\mathcal{B}(B^{-}\to D^{0}\tau^{-}\bar{\nu}_{\tau})/\mathcal{B}(B^{-}\to D^{0}\mu^{-}\bar{\nu}_{\mu})$ are measured, assuming isospin symmetry, using a sample of proton-proton collision data corresponding to 3.0 fb${ }^{-1}$ of integrated luminosity recorded by the LHCb experiment during 2011 and 2012. The tau lepton is identified in the decay mode $\tau^{-}\to\mu^{-}\nu_{\tau}\bar{\nu}_{\mu}$. The measured values are $\mathcal{R}(D^{*})=0.281\pm0.018\pm0.024$ and $\mathcal{R}(D^{0})=0.441\pm0.060\pm0.066$, where the first uncertainty is statistical and the second is systematic. The correlation between these measurements is $\rho=-0.43$. Results are consistent with the current average of these quantities and are at a combined 1.9 standard deviations from the predictions based on lepton flavor universality in the Standard Model.Comment: All figures and tables, along with any supplementary material and additional information, are available at https://cern.ch/lhcbproject/Publications/p/LHCb-PAPER-2022-039.html (LHCb public pages

Research Progress on Curved Plates in China: Applications in Architecture

Curved surfaces can give plates a unique aesthetic effect and physical advantages in acoustics and optics. Assembling such curved plates can greatly improve the image of buildings and enrich their functions. It is thus not surprising to notice that their wide applications in designed or completed buildings in China have become a trend. Thus, this study offers a comprehensive summary of the application progress of curved plates in the architectural field from three aspects: image expression, acoustic characteristics, and optical characteristics. On this basis, future directions are proposed. The main findings or suggestions are as follows: (1) climate harshness has increased recently, and the safety of structures and materials and the coupling effect of the two must be fully considered when designing the shapes of curved surface buildings; (2) research on the mechanism and numerical calculation of curved diffuser systems with different sizes and curvatures needs to be further developed; and (3) experimental studies of various and complex curved plates and different conditions to explore their optimal reflectivity, transmittance, absorptivity, and other optical properties will be an important development direction

Peripheral nerve stimulation for lower-limb postoperative recovery: A systematic review and meta-analysis of randomized controlled trials

Patients undergoing lower-limb orthopedic surgery may experience multiple postoperative complications. Although peripheral nerve stimulation (PNS) is a promising non-pharmacological approach that has been used in lower-limb postoperative recovery, the clinical efficacy of PNS remains inconclusive. This study systematically searched three databases (PubMed, Embase, and Cochrane Library) for randomized controlled trials (RCTs) that examined the treatment effects of PNSs in patients who underwent lower-limb orthopedic surgery up to September 29, 2023. Two investigators independently identified studies, extracted data, and conducted meta-analyses with Review Manager 5.4. The outcomes were pain relief (measured by reductions in pain intensity and analgesic consumption) and functional improvements (range of motion [ROM] and length of hospitalization [LOH]). A total of 633 patients including 321 in the experimental groups and 312 in the control groups from eight RCTs were included. PNS showed no significant effect on pain intensity, while analgesic consumption was marginally significantly reduced in the experimental group. Furthermore, no significant differences were observed regarding functional improvements in ROM or LOH after the intervention. Although PNS had no significant effect on pain relief or functional improvements, the intervention exhibited a marginally significant reduction in analgesic consumption. Future trials should be conducted with larger sample sizes, longer follow-up periods, and more varied stimulation parameters

Facile Functionalization of Natural Peach Gum Polysaccharide with Multiple Amine Groups for Highly Efficient Removal of Toxic Hexavalent Chromium (Cr(VI)) Ions from Water

The development of low-cost adsorbent with excellent adsorption property remains a big challenge. Herein, the functionalization of natural peach gum polysaccharide (PGP) with multiple amine groups for the removal of toxic Cr­(VI) ions from water was studied. The obtained PGP-NH2 gel exhibited high-removal efficiency (>99.5%) toward Cr­(VI) ions, especially with relatively low initial concentration of Cr­(VI) ions (≤250 mg/L). The influences of pH, ionic strength, contact time, initial concentration, and temperature on the adsorption of Cr­(VI) ions were systematically investigated. The PGP-NH2 gel showed rapid adsorption rate and could reach adsorption equilibrium within about 40 min. The Cr­(VI) ion uptake process could be described by pseudo-second-order kinetic and Langmuir isotherm models. The maximum adsorption capacity of PGP-NH2 gel could reach 188.32 mg/g. Thermodynamic investigation results indicated the spontaneous and exothermic characteristic of the uptake process. Moreover, the PGP-NH2 gel also exhibited favorable reusability, and 135.52 mg/g of adsorption capacity was retained even after being reused for five times. Considering its low cost and superior uptake property, the PGP-NH2 gel holds a great promise for employing as an adsorbent to treat Cr­(VI) ion-containing wastewater

Research Progress on Curved Plates in China: Applications in Architecture

Curved surfaces can give plates a unique aesthetic effect and physical advantages in acoustics and optics. Assembling such curved plates can greatly improve the image of buildings and enrich their functions. It is thus not surprising to notice that their wide applications in designed or completed buildings in China have become a trend. Thus, this study offers a comprehensive summary of the application progress of curved plates in the architectural field from three aspects: image expression, acoustic characteristics, and optical characteristics. On this basis, future directions are proposed. The main findings or suggestions are as follows: (1) climate harshness has increased recently, and the safety of structures and materials and the coupling effect of the two must be fully considered when designing the shapes of curved surface buildings; (2) research on the mechanism and numerical calculation of curved diffuser systems with different sizes and curvatures needs to be further developed; and (3) experimental studies of various and complex curved plates and different conditions to explore their optimal reflectivity, transmittance, absorptivity, and other optical properties will be an important development direction

500-kHz Level High Energy Double-Pass Nd:YVO4 Picosecond Amplifier with Optic–Optic Efficiency of 51%

We have demonstrated a high pulse energy and high optic–optic efficiency double-pass picosecond (ps) master oscillator power amplifier system of 1064 nm at a pulse repetition rate of 500 kHz. A 500 kHz, 7.68 μJ picosecond laser is used as the seed laser. Through one stage double-pass traveling-wave amplifier, a maximum output power of 16.19 W at a pump power of 31.7 W is generated with the optic–optic efficiency of 51.07%. The output pulse duration is 17.6 ps, corresponding to the pulse energy of 32.38 μJ. The beam quality factor M 2 were measured to be 1.28 and 1.17 along the x, y axis direction, respectively