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AbstractBackground Atelectasis affects approximately 90% of anaesthetized patients, with laparoscopic surgery and pneumoperitoneum reported to exacerbate this condition. High-frequency oscillation therapy applies continuous positive pressure pulses to oscillate the airway, creating a pressure difference in small airways obstructed by secretions. This process helps reduce peak airway pressure, open small airways, and decrease atelectasis incidence, while also facilitating respiratory tract clearance. This study examines the efficacy of high-frequency oscillation on reduction of atelectasis in laparoscopic cholecystectomy (LC) patients under general anaesthesia, evaluated using lung ultrasound.Methods Sixty-four patients undergoing laparoscopic cholecystectomy were randomly divided into a control group and a high-frequency oscillation (HFO) group. Both groups underwent total intravenous anaesthesia under invasive arterial monitoring. The HFO group received a 10-minute continuous high-frequency oscillation therapy during surgery, while the control group received no intervention. Lung ultrasound evaluations were performed three times: five minutes post-intubation (T1), at the end of the surgery (T2), and before leaving the Post-Anaesthesia Care Unit (PACU; T3). Blood gas analysis was performed twice: prior to induction with no oxygen supply and before PACU discharge (oxygen supply off).Results The HFO group displayed a significantly lower incidence of atelectasis at T3 (57.5% vs. 90.3%, OR 6.88, 95%CI (1.74 to 27.24)) compared to the control group. Moreover, the HFO group’s PaO2 levels remained consistent with baseline levels before PACU discharge, unlike the control group. Although there was no significant difference in LUS scores between the groups at T1 (8.56 ± 0.15 vs. 8.19 ± 0.18, p = 0.1090), the HFO group had considerably lower scores at T2 (13.41 ± 0.17 vs.7.59 ± 0.17, p

The semiconductors, such as TiO2, CdS, ZnO, BiVO4, graphene, produce good applications in photocatalytic water splitting for hydrogen production, and great progress have been made in the synthesis and modification of the materials. As a two-dimensional layered structure material, graphitic carbon nitride (g-C3N4), with the unique properties of high thermostability and chemical inertness, excellent semiconductive ability, affords good potential in photocatalytic hydrogen evolution. However, the related low efficiency of g-C3N4 with fast recombination rate of photogenerated charge carriers, limited visible-light absorption, and low surface area of prepared bulk g-C3N4, has called out the challenge issues to synthesize and modify novel g-C3N4-block photocatalyst. In this review, we have summarized several strategies to improve the photocatalytic performance of pristine g-C3N4 such as pH, morphology control, doping with metal or non-metal elements, metal deposition, constructing a heterojunction or homojunction, dye-sensitization, and so forth. The performances for photocatalytic hydrogen evolution and possible development of g-C3N4 materials are shared with the researchers interested in the relevant fields hereinto.

In this work, we reported a porous supramolecular framework (A) constructed of a symmetric tetramethylcucurbit[6]uril (TMeQ[6]) in aqueous HCl solutions; the driving force was the outer surface interaction of cucurbit[n]urils, as well as hydrogen bonding between latticed water molecules and portal carbonyl oxygens of TMeQ[6]. Adsorption experimental results revealed that the porous supramolecular framework can absorb certain fluorophore guests (FGs) to form luminescent assemblies (FG@As) by fluorescence enhancement or colour change, and some of them can respond to certain volatile organic compounds. Thus, the TMeQ[6]-based supramolecular framework could be used as a sensor for certain gas or volatile compounds.

A host-guest assembly, [(C40H44N24O12)·(C6H5NO3)8·13(H2O)] (1), based on a partial substituted cucurbituril, α,δ-tetramethylcucurbit[6]uril (TMeQ[6]), and 4-nitrophenol was synthesized and structurally characterized by single-crystal X-ray diffraction. A combination of hydrogen-bonding between the latticed water molecule and the hydroxyl group of 4-nitrophenol, the hydroxyl group of 4-nitrophenol and the carbonyl groups lining the portals in additon, the C-H···Ã€ interactions between the 4-nitrophenol molecules could be the driving forces of formation such an exclusion host-guest assembly.

Three barrel-shaped artificial molecular capsules 1-3, based on normal cucurbit[5]uril (Q[5]) and decamethylcucurbit[5]uril (Me10Q[5]), were synthesized and structurally characterized by single-crystal X-ray diffraction. Encapsulation of a chlorine anion in the cavity of a Q[5] or Me10Q[5] to form closed a molecular capsule with the coordinated metal ions or coordinated metal ions and water molecules in the crystal structures of these compounds is common. The three complexes [Pr2(C30H30N20O10)Cl3(H2O)13]3+3Cl-·5H2O (1), [Sr2(C40H50N20O10)(H2O)4Cl]3+3Cl-·2(HCl) 19H2O (2) and [K(C40H50N20O10)(H2O)Cl]·[Zn(H2O)2Cl2]·[ZnCl4]2-·2(H3O)+·8H2O (3) all crystallize as isolated molecular capsules.

The synthesis, and X-ray crystal structure of the inclusion host-guest complex of dodecamethylcucurbit[6]uril (DDMeQ[6]) with 1,4-dihydroxybenzene (DHOBEN) are reported. The complex crystallizes in the space group P21/c (No.14) with a =12.2847(4), b = 12.6895(4), c = 15.1310(4) Å, α = 74.6960(10), β = 71.4090(10), γ = 86.5090(10)° and Z = 1. A novel approach to dodecamethylcucurbit[6]uril synthesis is also described. To separate dodecamethylcucurbit[6]uril, 1,4-dihydroxybenzene is used as a guest molecule for crystallization of the fully methyl-substituted cucurbituril. The driving force for the self-assembled inclusion host-guest complex can be attributed to not only the cavity interaction of dodecamethylcucurbit[6]uril (host), but also to the hydrogen bonding between the carbonyl oxygen at the portals of the host and the hydroxy groups of the guest.

In the title compound, C17H12O4, there is an intramolecular O—H...O hydrogen bond. The dihedral angle between the indane ring system [maximun deviation = 0.023 (2) Å] and the benzene ring is 37.42 (9)°.

In the title compound, C8H12N4OS, an intramolecular N—H...O hydrogen bond links the imine N atom to the oxo O atom. In the crystal, molecules are linked by intermolecular N—H...O and N—H...S hydrogen bonds, forming a two-dimensional framework.

In the title compound, C12H11N3O3S·H2O, the pyridine ring makes a dihedral angle of 24.78 (14)° with the phenyl ring. Intramolecular N—H...O and intermolecular O—H...O hydrogen bonds are observed and stabilize the packing in the crystal structure.

The asymmetric unit of the title compound, (C24H26N2)[ZnCl4], consists of two 2,2′-(hexane-1,6-diyl)diisoquinolinium cations and two [ZnCl4]2− complex anions. The [ZnCl4]2− anions have a distorted tetrahedral geometry. The dihedral angles between the isoquinoline rings of the two cations are nearly equal [16.1 (2) and 16.3 (2)°]. In the crystal structure, the ordered linear formation is aggregated by weak intermolecular π–π stacking interactions between neighboring isoquinoline pyridine rings with a centroid–centroid distance of 3.779 (4) Å.

In the crystal of the title compound, [Ni(NO3)2(C18H10N4)(H2O)]·H2O, the NiII ion is coordinated in a distorted octahedral geometry by two N atoms of the 1,10-phenanthroline moiety of the ligand, three O atoms from two nitrate anions and an O atom from one water molecule. O—H...O hydrogen bonds between the coordinated and the solvent water molecules and between these water molecules and the nitrate O atoms help to establish the crystal packing.

The organic cation of the title salt, C17H12N4O2+·2Cl−·H2O, is nearly planar, the dihedral angle between two pyridine rings being 2.53 (16)° and that between the pyridinum and furan rings being 4.17 (19)°. Molecules are linked via N—H...O, N—H...Cl and O—H...Cl hydrogen bonds, forming a three-dimensional framework and π–π stacking interactions help to stabilize the crystal structure [the imidazole–pyridine and imidazole–benzene centroid–centroid distances are 3.501 (3) and 3.674 (3) Å; respectively].

The asymmetric unit of the title compound, C16H24Br2N2O2, contains two independent molecules, each which has two intramolecular N—H...O hydrogen bonds linking the amine N atoms to the enolic O atoms of the same acacH-imine unit. In the crystal, the molecules are lined up by intermolecular weak C—H...O hydrogen bonds, forming two vertical each other two-dimensional chains along the a axis and b axis of the unit cell, respectively.

The crystal of the title compound, (C22H22N2)[ZnCl4], consists of 2,2′-(butane-1,4-diyl)diisoquinolinium organic cations and [ZnCl4]2− complex anions. The cation is located across a twofold axis and the ZnII atom of the anion is located on the other twofold axis. The centroid–centroid distance between parallel pyridine rings of neighboring molecules is 3.699 (3) Å, but the face-to-face separation of 3.601 (3) Å suggests there is no significant π–π stacking in the crystal structure.

The molecules of the title compound, C15H16N2O4, are linked via N—H...O hydrogen bonds, forming undulating one-dimensional chains. Adjacent chains are linked by weak C—H...π interactions, forming a three-dimensional network.

In the title compound, C10H12N8O4·H2O, prepared from the reaction of glycoluril with paraformaldehyde, the organic molecule has mm symmetry. The asymmetric unit comprises one quarter of the molecule and a half-molecule of water. The dimer is formed by bridging two glycoluril molecules with methylene groups at the 1 and 6 positions. In the crystal structure, molecules are linked via N—H...O and O—H...O hydrogen bonds, forming a two-dimensional framework.

In the structure of the title compound, C37H40N4O8, pentaerythrityltetramine is bonded to four o-vanillin molecules, forming a four-armed Schiff base molecule. These molecules are connected by intermolecular C—H...O hydrogen bonds. Intramolecular C—H...N and O—H...N hydrogen bonds are also present.

In the crystal structure of the title compound, C6H8N2O·CH4N2O·H2O, molecules are linked via N—H...O, O—H...N and O—H...O hydrogen bonds, forming a three–dimensional framework.

In the crystal structure of the title compound, C13H11N4O3+·Cl−, the dihedral angle between the two pyridine rings is 9.72 (9) Å. Ions are linked via N—H...Cl, O—H...Cl and O—H...O hydrogen bonds, forming a three-dimensional framework.

The organic cation in the title compound, C24H32N42+·2Cl−·3H2O, is situated on an inversion centre. The cations, anions and water molecules are linked via N—H...O, N—H...Cl, O—H...O and O—H...Cl hydrogen bonds and C—H...π interactions, forming a three-dimensional framework.

The organic cation in the title compound, C14H18N22+·2Br−·2H2O, is situated on an inversion centre. The cations, anions and water molecules are linked via O—H...Br, C—H...Br and C—H...O hydrogen bonds, and π–π stacking interactions between adjacent pyridine rings, with a centroid–centroid separation of 3.8518 (17) Å.

The asymmetric unit of the title compound, C18H26N22+·2Br−·2H2O, consists of one-half of the organic cation, one Br− anion and one water molecule. The organic cation is situated on a centre of inversion. The dihedral angle between the pyridine ring and the plane of the central linkage is 59.3 (1)°. The cations, anions and water molecules are linked via O—H...Br, C—H...Br and C—H...O hydrogen bonds, forming a three-dimensional framework.

In the title compound, C17H14O6, the benzopyran ring system is essentially planar and forms a dihedral angle of 6.84 (4)° with the other benzene ring. In the crystal structure, centrosymmetrically related molecules are linked into dimers by O—H...O hydrogen bonds. The crystal packing is controlled by C—H...π and π–π stacking interactions involving the benzopyran and benzene rings, with centroid–centroid distances between 3.645 (2) and 3.986 (2) Å.

Recently, sustainable economic performance (SEP) has been the foremost requirement due to uncertainty of the economy and environment. This issue needs best practices and governance and also needs researchers' focus. Thereby, the paper aims to assess green supply chain (SC) practices, green SC governance and their role in the achievement of SEP in the manufacturing sector of China. The paper also attempts to explore the moderating effect of organizational support in proposed framework. PLS-SEM model was employed to test model's reliability and validity. The very same method has applied to test the linkage among outlined constructs. Obtained results confirms the moderating impact of organizational support among traditional governance, relational governance and the achievement of SEP in the manufacturing industry in China. This article provides guidelines to the regulators in developing policies related to the achievement of SEP using green SC practices and governance. [ABSTRACT FROM AUTHOR]

The objective of this study is to examine the role of open innovation practices to promote globalization. For this purpose, this study considered two open innovation practices: external knowledge and supplier involvement. A survey was carried out to collect primary data from the respondents. This study preferred Chinese small and medium-sized enterprises (SMEs) to examine the role of open innovation in globalization. Data were collected from the employees of SMEs in China. By employing Structural Equation Modeling, this study addressed the important insights for academicians and practitioners. It is concluded that; open innovation practices have key role to promote globalization. The promotion of open innovation practices among the Chinese SMEs can increase the globalization potential. The strategies of open innovation led to increase in business collaboration across the border business organizations. The business collaboration between the SMEs of various countries is the best way to enhance globalization by increasing the level of social capital. Therefore, those institutions who want to promote globalization should promote open innovation practices among the business organizations. [ABSTRACT FROM AUTHOR]

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A symmetric tetramethylcucurbit[6]uril-based porous supramolecular assembly was prepared in an aqueous H2SO4 solution (5 M). The driving force for the formation of this assembly is mainly the outer surface interaction of Q[n], which includes the ion-dipole interaction of SO4 2- anions and the positive electrostatic potential of the outer surface of the symmetric tetramethylcucurbit[6]uril (TMeQ[6]), the dipole-dipole interactions between the positive electrostatic potential of the outer surface of TMeQ[6] and portal carbonyl oxygens of TMeQ[6], and the hydrogen bonding between lattice water molecules and portal carbonyl oxygen atoms in TMeQ[6]. The TMeQ[6]-based porous supramolecular assembly exhibits the characteristics of absorbed fluorophore guests (FGs), such as dyes and polycyclic compounds with different fluorescence characteristics. Moreover, the resulting luminescent assemblies (FG@As) can respond to certain volatile organic compounds; in particular, the luminescent assemblies of rhodamine B or pyrene display a unique fluorescence enhancement in response to methanol. [ABSTRACT FROM AUTHOR]

Using an established method, we isolated a large quantity of cucurbit[10]uril (Q[10]) and prepared Q[10]-based supramolecular assemblies via different approaches. For example, the structure-directing agent [CdCl4]2- was used or the Q[10] molecule itself acted as a self-structure-directing agent to form different Q[10]-based supramolecular assemblies through the outer surface interaction of Q[10]. Generally, the Q[10]-based supramolecular assemblies possess porous features that suggest that Q[n]-based compounds could be used to manufacture molecular sieves and sensors and applied in absorption and separation technologies. [ABSTRACT FROM AUTHOR]

The coordination and supramolecular assemblies of potassium/ lanthanide cations to perhydroxycucurbit[5]uril in the presence of [PMo12O40]3- anions show significant differences, which could be used for the isolation of light lanthanides from their heavier counterparts. [ABSTRACT FROM AUTHOR]

In the present work, we describe three cucurbit[7]uril-based coordination supermolecular self-assemblies in the presence of [MtransCl4]2-. It can affect the construction of Q[7]/metal ionsbased coordination polymers, at the same time it can result in the formation of Q[7]-based supramolecular assemblies when introducing the [MtransCl4]2- into the Q[7]/metal ions system. [ABSTRACT FROM AUTHOR]

The coordination and supramolecular assemblies of Q[8] with lanthanides in the presence of [CdCl4]2- anions show significant differences, which could be used for the isolation of light lanthanides from their heavier counterparts. [ABSTRACT FROM AUTHOR]

A number of linear coordination polymers have been assembled from lanthanide cations (Ln3+) and cucurbit[7]uril (Q[7]) in the presence of [CuCl4]2-or [CoCl4]2- anions acting as inorganic structure inducers in HCl solution. X-ray diffraction analysis has revealed that they form three groups of isomorphous structures. Generally, the complexes of Q[7] with light lanthanide cations (those with atomic number below that of neodymium (Nd3+)) are in one group. The other two groups, in which the lanthanide cation has atomic number greater than that of europium (Eu3+), seem to follow no obvious rule. For example, the complexes of Q[7] with Eu3+ and Gd3+cations are in the second group in the presence of [CuCl4]2- anions, while they are in the third group in the presence of [CoCl4]2- anions. However, whatever group a given complex belongs to, they all show a common honeycomb-patterned supramolecular assembly, in which [CuCl4]2-or [CoCl4]2- anions form a honeycomb structure. The Ln3+ cations then coordinate to neighboring Q[7] molecules to form 1D coordination polymers that are inserted into the channels of the honeycomb framework, such that each individual coordination polymer is surrounded by [CuCl4]2-or [CoCl4]2- anions [ABSTRACT FROM AUTHOR]

A strategy of using organic guest-induced formation of polymers or frameworks based on the coordination of metal ions and cucurbit[n]urils was developed. Using this strategy, a compound with a stoichiometry of {Rb2(μ-OH)(H2O)2(Hyq@Q[7])2}·Cl has been synthesized. X-ray crystallography, shows the crystal structure to be a novel three dimensional infinite framework, constructed by the Q[7] pairs through the hydroquinone-induced coordination of the rubidium unit to the portal oxygens of the Q[7]s. [ABSTRACT FROM AUTHOR]

The interaction between two partially methyl-substituted cucurbiturils, a sym-tetramethyl-substituted cucurbit[6]uril (TMeQ[6]) and a meta-hexamethyl-substituted cucurbituril (m-HMeQ[6]), with the hydrochloride salt of benzidine (g1·HCl) and the analogue bis(4-aminophenyl) methane (g2·HCl) was investigated by single crystal X-ray diffraction determination, 1H NMR spectroscopy, electronic absorption spectroscopy and fluorescence spectroscopy. Single crystal X-ray diffraction determination showed the two guest compounds were excluded at the portals of the partial methyl-substituted cucurbiturils in the solid state. The 1H NMR spectroscopic analysis in aqueous solution supported the crystallographic results in which an excluding or portal interaction occurs between the host and guest. Aqueous absorption spectrophotometric and fluorescence spectroscopic analysis defined the stability of the host–guest exclusion complex at pH 5.6 with a host : guest ratio of 1 : 1, which forms quantitatively as ∼105L mol−1for the TMeQ[6]–g1 system. The host : guest ratio of 2 : 1 forms quantitatively as ∼1010L2mol−2for the m-HMeQ[6]–g2 system. The experimental results are in good agreement with HF and B3LYP computational approaches with a moderate-sized basis set. [ABSTRACT FROM AUTHOR]

Diastereopure (1R,2R)-N,N′-bis(acetylacetone)cyclohexanedi-imine L1and its corresponding (1R,2R)L1/(1S,2S)L2enantiomeric mixture react with AgNO3to yield the unusual coordination polymer [Ag2(L1)(L2)(NO3)2]n(1) and the unique trimetallic discrete species {[Ag3(L1)3(μ3-O,O,O-NO3)(H2O)3]2(NO3)}(NO3)3·8.5H2O (2) which incorporates a symmetrical μ3-bridging nitrato group that gives rise to a C3-symmetric triskelion motif; both species also feature γ-carbon η1aryl-like coordination of neutral bridging acetylacetone-imine units to the respective Ag(I) centres. [ABSTRACT FROM AUTHOR]

p-Hydroxybenzoic acid acts as a template in the presence of KI for the self-assembly of cucurbit[5]uril, which arranges into 6-membered ring structures. These form hexagonal netting sheets, superimposed upon one another to create continuous channels. This solid material is absorbent to volatile organics, ranging in size from methanol to 1,4-dioxane. [ABSTRACT FROM AUTHOR]