Search

Purpose To evaluate the extent of tunnel widening after anterior cruciate ligament reconstruction (ACLR) using the all-inside technique and to establish its correlation with patient-reported clinical outcomes and femoral graft bending angle (GBA). Methods Tunnel widening was evaluated using computed tomography (CT)-based three-dimensional (3D) models, and the femoral GBA was directly measured on CT images using the Picture Archiving and Communication System (PACS) software. Clinical follow-up was routine procedure, and patient-reported clinical outcomes mainly included International Knee Documentation Committee (IKDC), Lysholm, and Knee Injury and Osteoarthritis Outcome Scores (KOOS) scores, and subjective knee stability assessment. Results Fifty-two patients received standard all-inside ACLR, with a median follow-up of 6 months. Reconstructed anterior cruciate ligaments (ACLs) were scanned during the first 3 days and 6 months after surgery. On both the femoral and tibial sides, bone tunnels were most significantly enlarged at the articular aperture segment; the femoral tunnel was 9.2 ± 1.3 mm postoperatively and was significantly enlarged by 32% to a mean tunnel diameter of 12.1 ± 2.0 mm at 6 months after surgery. Moreover, the extent of tunnel enlargement gradually decreased as the measured levels approached those of the bone cortex. The femoral tunnel center was shifted into the anterior and distal direction, and the tibial tunnel center was shifted into the posterior and lateral direction. Additionally, the mean femoral GBA was 105.9° ± 8.1° at the 6-month follow-up. Tunnel enlargement and GBA were not significantly correlated with patient-reported outcomes. Conclusions Femoral and tibial tunnels were significantly greater and eccentrically shifted at the 6-month follow-up after all-side ACLR. However, the extent of tunnel widening does not markedly affect the short-term clinical outcomes. Meanwhile, the femoral GBA was not significantly correlated with femoral tunnel widening or patient-reported outcomes. Although the tunnel widening following all-inside ACLR was not associated with clinical outcomes, it potentially caused difficulties in revision ACLR. Level of evidence Level IV.

Osteoarthritis (OA) is a common joint disease that mainly results in chronic pain, stiffness and dysfunction in elderly individuals. The molecular mechanisms in the pathogenesis of OA are still unclear, and available treatments are unable to slowdown the development of OA or reverse the tissue damage. Circular RNAs (circRNAs), a novel type of non-coding RNA, are ubiquitous, stable, evolutionally conserved, tissue-specific and functional. An increasing number of studies have revealed that many circRNAs are differentially expressed in OA-affected joint tissues and engage in the pathogenesis of OA by functioning as miRNA sponges. In this review, we briefly introduce the biogenesis, characteristics and functions of circRNAs, and shed light on the important role of circRNAs in the occurrence and progression of OA and their potential diagnostic and therapeutic value in this disease based on the research over the last five years.

Although fluorescein has been a traditional fluorescence dye, little reports are found about the role of H 2 O on its spirolactam ring dynamic balance, emission mechanism and aggregation behavior. Some reports about 5-azidofluorescein fluorescence are inaccurate. In this paper, the fluorescence of three typical compound, 5-azidofluorescein ( 1 ), 5-aminofluorescein ( 2 ) and fluorescein ( 3 ) were restudied. It was found: (i) H 2 O is believed to act as a scissors for Ph-O bond of spirolactam ring, and this process is irreversible even by heating and irradiating; (ii) Azide moiety does not quench fluorescence of fluorescein system, 5-azidofluorescein exhibits strong green fluorescence in 100% water, the fluorescence is originating from the molecular aggregation induced emission (AIE); (iii) The theoretical base, optimized structures and transition features of fluorescence emissions of 1 o , 2 o and 3 o (opening form) and 1 c (closing form) were well certified by theoretical calculation (DFT); (iv) On this base, the reaction between 1 and H 2 S or NO sequentially is well understood.

Salen demonstrates aggregation-induced emission (AIE) effect in aqueous solution and solid state with green fluorescence (salen = N,N′-Ethylenebis(salicylimine)). The reaction of salen with Al3+ results in [Al(salen)(H2O)2]+ directly. [Al(salen)(H2O)2]+ exhibits an obvious assembly phenomenon: monomer exists in organic solution with blue fluorescence while self-assembly polymer forms in aqueous solution and crystal state emitting green fluorescence, we rename it as Restriction of Coordinated Water Motions (RCWM) effect. Moreover, the self-assembly of [Al(salen)(H2O)2]+ has been observed in different part of cells: green fluorescence in hydrophilic region and blue fluorescence in hydrophobicity region in the same time. The photophysical processes are verified by fluorescence spectra, ESI–MS, X-ray diffractometer. ESIPT effect of salen and fluorescence spectra of [Al(salen)(H2O)2]+ have been certified by theoretical calculation. Therefore, salen and [Al(salen)(H2O)2]+ can act as an ideal model for the combination of organic AIEgen and metal complex self-assembly both in aqueous solution and crystal state.

Laser-induced periodic surface structure (LIPSS) is a universal phenomenon which occurs for both continuous laser and pulsed laser. Recently, most studies are focus on LIPSS irradiated by fs laser. However, LIPSS irradiated by continuous laser still need to be carefully studied. Here, We study LIPSS in silicon wafer irradiated by continuous laser for different duration time and power. For the same power, we can observe the evolution process of LIPSS for different time. It is surprising that the evolution process of LIPSS seems to be layered, which occurs for different power. The inner layer occurs at first, then the outer layer occurs. Our study can be used to control the formation of LIPSS.

Mn2+-Doped semiconductor nanocrystals or quantum dots have been extensively studied as potential yellow/orange/red phosphors due to the stable Mn2+-related emission tuned by its tetrahedral coordination environment in host lattices. However, it is still very difficult to objectively explore the location–performance relationship in conventional Mn2+-doped nanomaterials since the precise location information on Mn2+ dopants is generally unavailable due to their random distribution in host lattices. Herein, we purposely selected a specific supertetrahedral-nanocluster-based molecular crystal (OCF-40-ZnGaSnS, composed of isolated supertetrahedral T4-ZnGaSnS nanoclusters (NCs) with the formula [Zn4Ga14Sn2S35]12−) as a host lattice, and effectively controlled the relatively precise position of Mn2+ dopants in host lattices of T4-ZnGaSnS NCs by in situ substitution of Zn2+ sites by Mn2+ ions, and investigated the Mn2+-location-dependent red emission properties. The current study clearly indicates that a long-lifetime (∼170 μs) red emission centred at 625 nm at room temperature for lightly-doped [Zn3MnGa14Sn2S35]12− NCs with one Mn2+ dopant in its surface centre is very sensitive to temperature and dramatically red-shifts to 645 nm at 33 K upon the excitation of 474 nm. However, heavily-doped OCF-40-MnGaSnS (composed of T4-MnGaSnS NCs with the formula [Mn4Ga14Sn2S35]12−, in which four Mn2+ dopants are accurately located at its core in the form of Mn4S) gives the temperature-insensitive red emission with a longer wavelength (641 nm) and a shorter lifetime (42 μs) at room temperature. This phenomenon is pretty uncommon compared to other heavily Mn2+-doped semiconductors. Such differences in their PL properties are ascribed to Mn2+-location-induced lattice strain to different degrees in two Mn2+-doped supertetrahedral NCs. In addition, the Mn2+-related red emission of both samples can be predominantly induced by the direct excitation of Mn2+ ions and secondarily by indirect excitation through exciton energy transfer from host lattices to Mn2+ dopants. Consistently, the DFT calculations suggest that the emission of NCs originated from the transition from the low spin excited state of Mn2+ (4T1) to its high spin ground state (6A1). The calculation results also revealed that the emission wavelength of lightly-doped [Zn3MnGa14Sn2S35]12− NCs is not obviously affected by the temperature-induced thermal effect, but by temperature-induced structural contraction, while that of heavily-doped [Mn4Ga14Sn2S35]12− NCs is affected by both effects. The total temperature cooling effect on the emission of [Zn3MnGa14Sn2S35]12− NCs is the red-shift, while that on the emission of [Mn4Ga14Sn2S35]12− NCs is negligible, which is akin to the experimental results. This research opens up a new perspective and provides a feasible method to explore the location–performance relationship of other Mn2+-doped NCs.

Though ultrashort metal–metal distances (USMMD, dM–M < 1.900 A) were primarily realized between transition metals, USMMDs between main group metal atoms such as beryllium atoms have also been designed previously using two strategies: (1) formation of multiple bonding orbitals or (2) having favourable electrostatic attraction. We recently turned our attention to the reported species IH → Be2H2 ← IH (where IH denotes imidazol-2-ylidene) because the orbital energy level of its π-type HOMO is noted to be very high, which may result in intrinsic instability. In the present study, we combined the abovementioned strategies to solve the high orbital energy level problem without losing the ultrashort Be–Be distances. It was found that breaking of such π-type HOMO by addition of a –CH2– group onto the bridging position of two beryllium atoms led to the formation of IH → Be2H2CH2 ← IH species, which not only possesses an ultrashort Be–Be distance in the –Be2H2CH2– moiety, but also has a relatively low HOMO energy level. Replacing the IH ligands with NH3 and PH3 resulted in the formation of NH3 → Be2H2CH2 ← NH3 and PH3 → Be2H2CH2 ← PH3 species with similar features. The electronic structure analyses suggest that the ultrashort Be–Be distances in these species are achieved by the combined effects of the formation of two Be–H–Be 3c-2e bonds and having favourable Coulombic attractions between the carbon atom of the –CH2– group and two beryllium atoms. Remarkably, when the IH, NH3, and PH3 ligands were replaced by large ligands with bulky groups, such as 1,3-bis(2,6-diisopropyl phenyl)imidazol-2-ylidene (IDip), triphenylamine (NPh3), and triphenylphoshpine (PPh3), respectively, the resultant species IDip → Be2H2CH2 ← IDip, NPh3 → Be2H2CH2 ← NPh3, and PPh3 → Be2H2CH2 ← PPh3 exhibit good steric protection around the –Be2H2CH2– core. These species are thus examples for the experimental realization of species with ultrashort metal–metal distances between main group metals.

To explore the inhibitory effect of 2- (4-morpholine) -8- phenyl -4 hydrogen -1- benzo -4 ketone (LY294002) on proliferation of multiple myeloma cell U266 and its mechanism.U266 cells were cultured with 0, 5, 10, 20 µmol/L LY294002 for 24, 48 and 72 h, the cell viability was measured by MTT method, cell morphology was observed by acridine orange staining, cell cycle was measured by flow cytometry. The expressions of B-cell lymphoma-2 (BCL-2), BCL-2-associated X protein (BAX), Cyclin D1, Cyclin E and activation of phosphatidyl inositol 3 kinase (PI3K)/protein kinase B (AKT) signal pathway were measured by Western blot.U266 cell viability was reduced in time- and dose-dependent manner after treatment with 5, 10, 20 µmol/L of LY294002 for 24, 48, 72 h. The 5, 10, 20 µmol/L LY294002 leaded to cell nucleus dense and thick, and the cell cycle arrested in the GLY294002 can inhibit U266 cell proliferation via suppresion of activation of PI3K/AKT signal pathway.

The monocular vision odometry simplifies the hardware and the software as opposed to the stereo vision odometry, but it also has defect. When the vehicle is in motion, the camera's attitude changes inevitably, what lead that the method's performance degrades. To solve this problem, we proposed a monocular visual odometry based on the inverse perspective mapping (IPM). Attitude of the camera is monitored in real time by the attitude sensor when the vehicle is moving. Then the images of road surface photographed by camera became top view by using the IPM algorithm, after that, the characters of images can be calculated by the Speeded Up Robust Features (SURF) algorithm. By the random sample consensus (RANSAC) algorithm, the amounts of translation and rotation between two adjacent images can be concluded. Accordingly, the movement distance and the course of the vehicle can be worked out. In order to test the ranging accuracy of the method, both static and dynamic experiments were implemented. Static experiment showed that the average accuracy of ranging of this method achieved 1.6%. Dynamic experiment showed that the ranging accuracy achieved 6%, and the heading measurement error is less than 1.3°. Therefore, the method proposed in this paper is easy to operate, time-efficient, low cost, and the accuracy of the method in ranging and heading measurement are demonstrated.

In the process of 3D reconstruction of the target scene with the moving vehicle-borne single-line scanner, a method of monocular visual positioning is used to locate the exact position of the moving scanner. Attitude sensor, camera and the laser scanner are located on the same platform which is installed on the vehicle. Data can be collected synchronously. We obtained a top view according to the observation of camera's attitude by IPM. A series of planform are acquired at different moment. After dealing with these pictures with operations of extraction Speeded Up Robust Features (SURF), matching characteristic points and RANSAC algorism, we calculated the transformation matrix between two adjacent vertical views. The position and direction of the scanner at this moment can be calculated. On this basis, depending on the sensors' synchronization control algorithm, the original point clouds data got by laser scanner can be registered as a reference to the traveling track of the moving scanner, and then the 3D reconstruction of the target scene is established. Experiment result shows that this method is easy to operate, time-efficient, low cost, and the accuracy of the method in reconstructing 3D scene is demonstrated.