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The ability to grow properly sized and good quality crystals is one of the cornerstones of single-crystal diffraction, is advantageous in many industrial-scale chemical processes.sup.1-3, and is important for obtaining institutional approvals of new drugs for which high-quality crystallographic data are required.sup.4-7. Typically, single crystals suitable for such processes and analyses are grown for hours to days during which any mechanical disturbances--believed to be detrimental to the process--are carefully avoided. In particular, stirring and shear flows are known to cause secondary nucleation, which decreases the final size of the crystals (though shear can also increase their quantity.sup.8-14). Here we demonstrate that in the presence of polymers (preferably, polyionic liquids), crystals of various types grow in common solvents, at constant temperature, much bigger and much faster when stirred, rather than kept still. This conclusion is based on the study of approximately 20 diverse organic molecules, inorganic salts, metal-organic complexes, and even some proteins. On typical timescales of a few to tens of minutes, these molecules grow into regularly faceted crystals that are always larger (with longest linear dimension about 16 times larger) than those obtained in control experiments of the same duration but without stirring or without polymers. We attribute this enhancement to two synergistic effects. First, under shear, the polymers and their aggregates disentangle, compete for solvent molecules and thus effectively 'salt out' (that is, induce precipitation by decreasing solubility of) the crystallizing species. Second, the local shear rate is dependent on particle size, ultimately promoting the growth of larger crystals (but not via surface-energy effects as in classical Ostwald ripening). This closed-system, constant-temperature crystallization driven by shear could be a valuable addition to the repertoire of crystal growth techniques, enabling accelerated growth of crystals required by the materials and pharmaceutical industries. A method of growing crystals that does not require undisturbed solutions involves adding polyelectrolytes to the starter solution and shearing (that is, stirring)., Author(s): Jian-Ke Sun [sup.1] [sup.3] , Yaroslav I. Sobolev [sup.1] , Weiyi Zhang [sup.4] , Qiang Zhuang [sup.1] [sup.5] , Bartosz A. Grzybowski [sup.1] [sup.2] Author Affiliations: (1) Center for [...]

This paper introduces a beam‐scanning holographic antenna composed of a substrate‐integrated waveguide (SIW) feeding structure and a rectangular microstrip array. The antenna innovatively combines holographic theory with liquid crystal electrical tunability to realize single‐frequency large‐angle beam scanning function which can effectively solve the problem of beamforming reconfiguration in traditional array antenna systems. In this paper, the variation of dielectric constant of liquid crystal under different bias voltages is quantitatively analyzed. Additionally, the beam forming technology is analyzed under hologram amplitude weighting theory. The relevant theories are verified by manufacturing and testing. The prototype antenna achieves the ultra‐wide beam scanning angle of −63° to 63° at 36 GHz. [ABSTRACT FROM AUTHOR]

Along the development of ionic porous organic polymers, simple and efficient synthetic methods are actively pursued. Herein, the Debus–Radziszewski reaction is applied to synthesize ionic conjugated microporous polymers (iCMPs) in one step. A series of imidazolium‐linked iCMP‐X (X = 1, 2, 3) are developed for CO2 sorption and in situ conversion with epoxide into cyclic carbonates. The as‐synthesized iCMPs are characterized in detail by scanning electron microscope, solid‐state nuclear magnetic resonance, X‐ray photoelectron spectroscopy, X‐ray diffraction analysis, N2/CO2 sorption, and more. Among all synthesized iCMPs, iCMP‐1 possesses the highest specific surface area and in turn the strongest CO2 sorption capacity. Moreover, through a simple anion ion exchange reaction with halide, iCMP‐1 is transformed to iCMP‐1@Cl that embodies significant catalytic capability for converting CO2 into cyclic carbonates. [ABSTRACT FROM AUTHOR]

Microspheres are widely used as profile control and water plugging products at present. However, the current research on microspheres is mainly focused on oil displacement experiments. In order to solve this problem, based on the Bohai sea in the BZ of inhomogeneous reservoir conditions, this article has done the matching study on particle size and hole roar and the seepage research in porous medium by means of particle size analysis, pressure tests, single-phase block experiments, and the double tube parallel oil displacement experiments, revealing the characteristics of oil & water selective plugging and the mechanism of oil displacement in porous media. The results show that the average particle size of the microspheres increases from 4.857μm to 24.53μm, and the maximum expansion factor reaches 5.03 times after 72h of swelling in BZ25 oilfield water at 75 C. In the two-pipe parallel oil flooding experiment with the permeability of 1000mD and 3000mD respectively, the comprehensive recovery rate after the first water flooding is 28.06%, and the two-pipe average recovery rate is increased by 1.58% after the injection of 2000ppm microsphere with 0.3PV, and there is no significant increase in oil displacement efficiency. The comprehensive recovery rate reached 38.6% and increased by 8.99% after 4PV of subsequent water flooding, indicating that microsphere flooding effectively improved the water sweep efficiency of subsequent injection.

BACKGROUND: How parasitoids distinguish hosts from non‐hosts remains an unknown question. Chouioia cunea Yang (Eulophidae) is an important fall webworm parasitoid that attacks many forest and agricultural pests. To study the differences in the chemical clues used by C. cunea to distinguish host and non‐host plants, we used gas chromatography–mass spectrometry (GC–MS) to identify volatile compounds of two C. cunea hosts (Hyphantria cunea and Helicoverpa armigera) and two non‐hosts (Spodoptera exigua and Spodoptera frugiperda). Additionally, we used behavioral assays to compare the attraction of C. cunea to various compounds. RESULTS: The two natural host species were more attractive than the two non‐host species, in the following order: Hyphantria cunea > Helicoverpa armigera > S. exigua = S. frugiperda. The pupae of the natural hosts contained 1‐dodecene, which was not produced by the two natural non‐hosts. When the 'attractants' based on the difference between the species‐specific blend emitted by pupae and the optimal blend were sprayed onto the natural non‐host pupae, they significantly improved the attraction of C. cunea to the non‐host pupae. CONCLUSION: These results revealed that specific host‐produced volatile compounds guide C. cunea to distinguish between natural hosts and non‐hosts. Overall, this study provides a foundation for developing a behavior‐modifying strategy to re‐direct C. cunea attacks to control important non‐host pests. © 2023 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Cinnamaldehyde (CA) showed potent activity against melanoma in our previous study, and the structure of unsaturated aldehydes is envisaged to play a role. Nevertheless, its limited drug availability restricts its clinical application. Therefore, a series of CA analogues were synthesized to evaluate their anti-melanoma activities across various melanoma cell lines. These compounds were also tested for their toxicity against the different normal cell lines. The compound with the most potential, CAD-14, exhibited potent activity against the A375, A875 and SK-MEL-1 cells, with IC50 values of 0.58, 0.65, and 0.82 µM, respectively. A preliminary molecular mechanism study of CAD-14 indicated that it could inhibit the p38 pathway to induce apoptosis, and suppress tumor growth by inhibiting the expression of ENO1. Furthermore, an acute toxicity study depicted that CAD-14 has better safety and tolerability than CA in vivo. These findings indicate that CAD-14 might be a lead compound for exploring effective anti-melanoma drugs. [ABSTRACT FROM AUTHOR]

With the rapid development of energy storage technology, the operation of portable and wearable devices is inseparable from high energy density power supplies. However, the demand for high performance supercapacitors in movable smart electronics is still restrained by their insufficient areal capacitance and limited power/energy densities. In addition, some electroactive materials, including metal oxides, conductive polymers, graphene, porous carbons, etc., are inevitable to use extra adhesives for the preparation of electrode materials. In this work, integrated hierarchical graphitic porous carbon membranes used as the electrodes without adhesives are successfully synthesized, via pyrolyzing poly(ionic liquid)s (PILs)‐metal organic frameworks (MOFs) composite membranes. The asymmetric supercapacitor is assembled by the carbonized PIL‐MOF composite membrane and PILs‐derived porous carbon membrane, and exhibits significant areal capacitance with remarkable power and energy densities. In the two‐electrode system, the areal capacitance can reach 9.5 F cm−2 with an energy density of 1.91 mWh cm−2. In the fabricated all‐solid‐state supercapacitors, the areal capacitance and energy density achieved 3.2 F cm−2 and 0.65 mWh cm−2, respectively, exceeding most reported ones. Therefore, the integrated carbon membrane electrodes with high areal capacitance reveal great potential in miniaturized devices, and further show a wider application scope through regulating PILs. [ABSTRACT FROM AUTHOR]

Purpose: The study aims to explore the relationship and potential mechanisms between screen time and anxiety and have a clear understanding of the role of negative emotions and emotion regulation, thus providing guidance for Chinese college students to improve mental health.Methods: We conducted a questionnaire survey by selecting 1721 academic college students from 6 colleges and universities in 5 provinces in China, and the data were analyzed through the Process program of SPSS for mediating effect and moderating effect.Results: There is a significant positive relationship between screen time and anxiety, negative emotions play a mediating role between the two (indirect effect = 0.32, p < 0.001), mediating effect accounts for 59.88% of the total effect, and emotion regulation regulates the direct relationship between screen time and anxiety (interaction effect = 0.027, p < 0.001).Conclusion: This study sheds light on the potential mechanisms by which screen time affects anxiety in academic college students, providing a fresh perspective on anxiety reduction. Screen time positively affects anxiety levels, where negative emotions have a mediating role and emotion regulation has a moderating role. In the future, we can control screen ++time, increase physical activities, reduce negative emotions, and improve the emotional regulation ability to relieve anxiety, so as to improve the mental health of academic college students, and expect to have a positive impact on future learning, life, and planning. [ABSTRACT FROM AUTHOR]

Hen eggs are one of the most popular foods worldwide, and their safety is critical. Employing 16S rRNA full-length sequencing is an effective way to identify microorganisms on or in eggs. Here, hen eggs collected from poultry farms over four seasons, as well as from markets in Shanghai, were analyzed with third-generation sequencing. Firmicutes (44.46%) and Proteobacteria (35.78%) were the two dominant phyla, and Staphylococcus, Acinetobacter, Aerococcus, Psychrobacter, and Lactobacillus were the dominant genera. The dominant genera on the eggshell surfaces from the farms varied with the seasons, and the highest contamination of Staphylococcus (32.93%) was seen in the eggs collected during the summer. For the market samples, Pseudomonas was the most abundant in content, with Staphylococcus being the most-often genera found on the eggshell surfaces. Moreover, several potential pathogenic bacteria including Riemerella anatipestifer (species), Klebsiella (genus), and Escherichia/shigella (genus) were detected in the samples. The results revealed the impacts of weather on the microbiota deposited on an eggshell's surface, as well as the impacts due to the differences between the contents and the surface. The results can help disinfect eggs and guide antibiotic selection. [ABSTRACT FROM AUTHOR]

Human epidermal growth factor receptor 2 (HER2) is an important breast cancer marker that is abnormally expressed in 20–30% of breast cancer patients. Here, we report an electrochemical biosensor using carboxy-functionalized multi-walled carbon nanotubes (MWCNTs) and activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) on a highly conductive poly (3,4-ethylenedioxythiophene): polystyrene sulfonate (PEDOT:PSS) platform for efficient detection of HER2. In this work, PEDOT:PSS and AuNPs were first modified onto a glassy carbon electrode (GCE) to increase the signal transmission efficiency of the biosensor. Then, an aptamer-HER2-antibody (Apt-HER2-Ab*) sandwich structure was constructed to capture and immobilize the target HER2. Of note, the Ab* is a composite composed of Ab, poly ferrocene methyl methacrylate (PFMMA), and carboxyl-functionalized MWCNTs (Ab-MWCNTs-PFMMA). The BMP was attached to the electrode by forming an ester bond with the hydroxyl group on the carboxyl-functionalized MWCNTs, and triggering ARGET ATRP to attach FMMA to the MWCNTs. In addition, Ab was attached to the electrode by ester bonds with the MWCNTs. In the presence of highly conductive materials and a polymer, the biosensor showed high sensitivity and a good linear relationship between the current signal and HER2 concentration in the range of 10−2 to 103 ng mL−1, and the limit of detection (LOD) was 1.979 fg mL−1. The regression equation was I (μA) = 8.23905 lg[CHER2/ng mL−1] + 25.3585 (R2 = 0.995). Moreover, the biosensor still shows good detection performance in the complex environment of normal serum, which is promising for clinical applications. [ABSTRACT FROM AUTHOR]

Objectives: To determine the safety and efficacy of deep neuromuscular block (NMB) for endolaryngeal surgery. Data Sources: PubMed, Web of Science, Cochrane Library, Ovid Medline, Embase, China National Knowledge Infrastructure, Wanfang, VIP databases, and trial registry database. Methods: Inclusion criteria followed the PICOS principles: Participants, adults undergoing endolaryngeal surgery; Intervention, deep NMB performed during the surgery; Control, no‐deep NMB performed; Outcomes, primary outcome: the incidence of clinically acceptable surgical conditions. Secondary outcome: the incidence of intraoperative complications (including vocal fold movement and coughing) and total incidence of postoperative complications [including postoperative residual curarization (PORC), postoperative sore throat (POST), and postoperative nausea and vomiting (PONV)]. Study design, randomized controlled trials (RCTs). Duplicate publications, editorials, letters, abstracts, and reviews were excluded. Results: Four articles with 242 patients were identified for analysis. The results indicated that compared with no‐deep NMB, deep NMB provides a higher incidence of clinically acceptable surgical conditions (98.36% vs. 76.67%; relative ratio [RR] = 1.29, 95% CI: 1.07–1.56), a lower incidence of intraoperative complications (10.83% versus 37.16%; RR = 0.32; 95% CI: 0.21–0.49) (lower incidence of vocal fold movement [1.85% vs. 34%; RR = 0.08, 95% CI: 0.02–0.41] and coughing [15.53% vs. 38.78%; RR = 0.42, 95% CI: 0.27–0.66]). There were no differences in the overall incidence of postoperative complications (RR = 2.10, 95% CI: 0.12–36.40). Conclusions: Based on current published evidence, deep NMB provides better surgical conditions with a higher incidence of clinically acceptable surgical conditions and a lower incidence of intraoperative complications (lower incidence of vocal fold movement and coughing) without increasing the overall incidence of postoperative complications. Level of Evidence: 1 Laryngoscope, 133:2055–2065, 2023 [ABSTRACT FROM AUTHOR]

Aqueous electrolytes typically suffer from poor electrochemical stability; however, eutectic aqueous solutions—25 wt.% LiCl and 62 wt.% H3PO4—cooled to −78 °C exhibit a significantly widened stability window. Integrated experimental and simulation results reveal that, upon cooling, Li+ ions become less hydrated and pair up with Cl−, ice‐like water clusters form, and H⋅⋅⋅Cl− bonding strengthens. Surprisingly, this low‐temperature solvation structure does not strengthen water molecules' O−H bond, bucking the conventional wisdom that increasing water's stability requires stiffening the O−H covalent bond. We propose a more general mechanism for water's low temperature inertness in the electrolyte: less favorable solvation of OH− and H+, the byproducts of hydrogen and oxygen evolution reactions. To showcase this stability, we demonstrate an aqueous Li‐ion battery using LiMn2O4 cathode and CuSe anode with a high energy density of 109 Wh/kg. These results highlight the potential of aqueous batteries for polar and extraterrestrial missions. [ABSTRACT FROM AUTHOR]