Theoretical Study on Optoelectronic Properties of 1,4-Dithiazole-5,10-dihydrophenazine and Its B ← N-Fused Derivatives.

Recently, Liu et al. reported 1,4-dithiazole-5,10-dihydrophenazine (DTDHP) and its B ← N-fused derivative (DTHDHP-BF2), which were expected to show excellent optoelectronic properties (Angew. Chem. Int. Ed. 2022, 61, e202205893). However, their charge-transport performance and luminescence emission mechanisms have not been revealed. In this work, we used density functional theory (DFT) calculations to investigate the optoelectronic properties of DTDHP and DTHDHP-BF2 and analyzed the influence of the introduction of -BF2 on the basic parameters governing charge transport and injection in detail. Our calculation results showed that adding -BF2 could stabilize the frontier molecular orbitals and decrease the reorganization energies associated with electron transport due to the formation of B ← N bonds, and the intermolecular electronic couplings are greatly enhanced owing to the strong intermolecular F···H interactions. Based on the master equation coupled with the Marcus-Hush electron transfer theory, we theoretically predicted the charge transport properties of DTDHP and DTHDHP-BF2. The optimum hole mobility (3.87 cm2 V-1 S-1) and electron mobility (1.52 cm2 V-1 S-1) of DTHDHP-BF2 are, respectively, 3 and 9 times as high as the corresponding optimum values of compound DTDHP. Moreover, the assignments of multiple fluorescence bands in the experiment were confirmed by time-dependent density functional theory (TDDFT) calculations. The simulated emission spectra indicate that the experimental fluorescence maxima at 687 nm originates from the S1 → S0 transition of the double proton transfer phototautomer (T2H) of DTDHP, and the shoulder peak at ∼660 nm may be related to the excited-state single-proton transfer phototautomer (T1H); for DTHDHP-BF2, the experimental fluorescence maxima at 687 nm should be attributed to normal Stokes shifted emission, and the shifted fluorescence with a peak at 751 nm originates from the emission of the photodissociation product of DTHDHP-BF2.

The efficacy of robot-assisted surgery on minor basal ganglia cerebral hemorrhage with neurological dysfunction.

OBJECTIVE: This study aims to compare the outcomes of robot-assisted drainage and conservative treatment in minor basal ganglia hemorrhage (10ml< hemorrhage volume ≤ 30 ml) patients with neurological dysfunction, and analyze patients treated with robot-assisted drainage in order to optimize this treatment strategy. METHODS: In a retrospective study conducted in December 2021 to December 2023, minor basal ganglia cerebral hemorrhage patients with neurological dysfunction were enrolled from the Department of Neurosurgery, Shanghai Ninth People's Hospital. The patients included both the surgical (robot-assisted drainage) and conservative groups. The efficacy of robot-assisted drainage compared with conservative treatment in patients with minor cerebral hemorrhage and neurological dysfunction was evaluated by modified Rankin Scale (mRS) score after 3 months, muscle strength (grade 1 to 5) and cost of hospitalization. RESULTS: Of the patients included, 23 received robot-assisted drainage and 20 received conservative treatment. There were no significant differences in gender, age, history of hypertension and diabetes, muscle strength and mRS score at admission. Female patients accounted for 32.6%, and male patients accounted for 67.4%. About 90% of the patients enrolled had a pre-existing hypertension history. The mRS score after 3 months indicated that prognosis of the patients was significantly better in the surgical treatment group than the conservative treatment group (favorable prognosis 69.57% VS. 35%, P = 0.034) while the patients underwent surgery paid higher hospital bills than patients treated conservatively. CONCLUSION: Compared with traditional conservative treatment, robot-assisted drainage surgery is more helpful to improve the prognosis of patients with minor basal ganglia hemorrhage (volume ≤ 30mL) accompanied by neurological dysfunction. Robot assisted surgery can safely and effectively remove the hematoma of minor basal ganglia hemorrhage, and there were 69.6% of surgery group patients had a good prognosis in this study.

Simple and active magnetic-field stabilization for cold atom experiments.

Cold atom experiments usually need a controllable and low-noise bias magnetic field to provide a quantization axis. Most labs need home-made stabilization of the field according to the actual setup, as commercially available power supply cannot directly satisfy their requirements. Here, by measuring the field fluctuations and active feedback modulating current supply of the applied magnetic field, we successfully demonstrate a field of 10.58 G with a stability to the level of 2.8 × 10-7 in a duration of 5 min. The root mean square noise is reduced to 0.05 mG, compared to the noise of 1.3 mG without stabilization. The coherence time of the magnetic-field sensitive transition between the rubidium ground states F=1,mF=-1 and 1,0, as measured by Rabi oscillation, is extended to 19.2 ms from the unstabilized value of 1.3 ms. This result is long enough for most experiments on quantum simulation and precision measurement. As our system has no passive magnetic shielding and additional compensation coils, it is highly simple and compact to provide the stable magnetic field and would be adapted to various applications with cold atoms.

The efficacy of paxlovid in elderly patients infected with SARS-CoV-2 omicron variants: Results of a non-randomized clinical trial.

Objective: To evaluate the efficacy of Paxlovid in treating Chinese elder patients infected with SARS-CoV-2 omicron variants. Materials and methods: We performed a non-randomized, controlled trial in Shanghai, China. Participants infected with SARS-CoV-2 omicron variants were enrolled. All patients were divided into the Paxlovid group or the control group according to the Chinese guideline (version 9). The nucleic acid shedding time was the primary endpoint. Results: According to the inclusion criteria, 142 patients infected with omicron variants were enrolled, 36 patients who did not receive paxlovid were assigned to the control group, and 106 were in the Paxlovid group. The baseline characteristics were similar in either group. No significant difference in BMI, age, time from onset to patient enrollment, the severity on first admission, vaccination status, comorbidity, first symptoms, and laboratory results were recorded. Compared to the control group, participants in the Paxlovid group had a shorter viral shedding time [11.11 (2.67) vs. 9.32 (2.78), P = 0.001]. Conclusion: In Chinese elder patients infected with the variant of SARS-CoV-2 omicron, our data suggest that Paxlovid can significantly reduce the nucleic acid shedding time.

Satellite-derived bathymetry using Landsat-8 and Sentinel-2A images: assessment of atmospheric correction algorithms and depth derivation models in shallow waters.

Satellite-derived bathymetry (SDB) has an extensive prospect in nearshore bathymetry for its high efficiency and low costs. Atmospheric correction and bathymetric modeling are critical processes in SDB, and examining the performance of related algorithms and models will contribute to the formulation of reliable bathymetry strategies. This study explored the effectiveness of three general atmospheric correction algorithms, namely Second Simulation of a Satellite Signal in the Solar Spectrum (6S), Atmospheric correction for OLI 'lite' (ACOLITE), and QUick Atmospheric Correction (QUAC), in depth retrieval from Landsat-8 and Sentinel-2A images using different SDB models over Ganquan Island and Oahu Island. The bathymetric Light Detection and Ranging (LiDAR) data was used for SDB model training and accuracy verification. The results indicated that the three atmospheric correction algorithms could provide effective corrections for SDB. For the SDB models except log-transformed band ratio model (LBR) and support vector machine (SVM), the impact of different atmospheric corrections on bathymetry was basically the same. Furthermore, we assessed the performance of six different SDB models: Lyzenga's model (LM), generalized additive model (GAM), LBR, SVM, multilayer perceptron (MLP), and random forest (RF). The bathymetric accuracy, consistency of bathymetric maps and generalization ability were considered for the assessment. Given sufficient training data, the accuracy of the machine learning models (SVM, MLP, RF) was generally superior to that of the empirical inversion models (LM, GAM, LBR), with the root mean square error (RMSE) varied between 0.735 m to 1.177 m. MLP achieved the best accuracy and consistency. When the depth was deeper than 15 m, the bathymetry error of all the SDB models increased sharply, and LM, LBR and SVM reached the upper limit of depth retrieval capability at 20-25 m. In addition, LM and LBR were demonstrated to have better adaptability in heterogeneous environment without training data.

Factors associated with prolonged viral shedding in older patients infected with Omicron BA.2.2.

Background: This study explores the risk factors associated with viral shedding time in elderly Chinese patients infected with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) omicron. Methods: Participants infected with SARS-CoV-2 omicron were enrolled in a retrospective study, and divided into two groups according to shedding time (≥10 days, "late clearance group" and <10 days, "early clearance group"). Results: A total of 180 patients were enrolled in the study (88 early, 92 late), with a median viral shedding time of 10 days and a mean age of 77.02 years. Prolonged SARS-CoV-2 omicron shedding was associated with old age (p = 0.007), lack of vaccination (p = 0.001), delayed admission to hospital after onset of diagnosis (p = 0.001), D-dimer (p = 0.003), and methylprednisolone treatment (p = 0.048). In multivariate analysis, vaccination (OR, 0.319, 95% CI, 0.130-0.786, p = 0.013), Paxlovid (OR, 0.259, 95% CI, 0.104-0.643, p = 0.004), and time from onset of diagnosis to admission (OR, 1.802, 95% CI, 1.391-2.355, p = 0.000) were significantly associated with viral clearance. Conclusions: Time from onset of diagnosis to hospitalization, lack of treatment with Paxlovid, and lack of vaccination were independent risk factors in elderly Chinese patients infected with SARS-CoV-2 omicron for prolonged viral shedding.

Combining subsidence theory and slope stability analysis method for building damage assessment in mountainous mining subsidence regions.

Ground subsidence and surface cracks caused by coal mining are typical man-made geological hazards that can severely damage the ecological environment and buildings. In China, within the theme of sustained and stable development, accurate assessment of mining-related building damage is paramount in order to address the contradiction between coal mining enterprises and building owners. Previous research in China focused mainly on the mining areas of plains, and only a few studies have considered building damage caused by intensive mining in mountainous areas. First, based on field investigation, this study located ground surface cracks and assessed the damage to buildings in the village of Nanyetou in Shanxi Province (China) attributable to the exploitation of the 15110 working face of the Baiyangling coal mine. Second, based on the mining subsidence law and boundary angle, the surface influenced boundary caused by underground mining was determined. However, as the existing subsidence theory cannot adequately explain the phenomenon of building damage, the damage was investigated from the perspective of slope stability analysis, and the slope safety factor before and after working face mining were calculated using the Janbu method. The analytical results showed that slope instability due to a decrease of the safety factor because of the coal mining activity was the principal reason for damage to the village buildings, a finding that was confirmed by field survey and InSAR monitoring displacement. The results of this study could provide guidance and reference for the assessment of building damage caused by underground mining in mountain areas.

Significant effects of vibrational excitation of reactant in K + H2 → H + KH reaction based on a new neural network potential energy surface.

The study of K + H2 collision has a long experimental history, but there have been few theoretical studies due to lack of a global potential energy surface (PES). In this study, a new global PES for the ground state of KH2 system was constructed based on numerous ab initio points, using the permutation invariant polynomial neural network method. The root mean square error (RMSE) of PES is very small (5.64 meV). On the new PES, time-dependent quantum wave packet (TDWP) and quasiclassical trajectory (QCT) calculations were carried out to study the dynamics of the K(2S) + H2(X1Σ+g) → H(2S) + KH(X1Σ+) reaction. Dynamics results show that (i) the K + H2(v = 0) → H + KH reaction scarcely occurred, (ii) the K + H2(v = 1) → H + KH reaction took place in small quantities, and (iii) the K + H2(v = 2) → H + KH reaction occurred in large quantities. This indicates that vibrational energy of the reactant is significantly more effective at promoting the reaction than the translational energy. This characteristic stems from a major physical model in reactive collisions: the vibrationally excited H2 molecule and K atom collide first in a T-geometric configuration and the vibrational motion of the H2 molecule helps separate the two H atoms a large distance after the collision. At a large H-H distance, a broad well exists on the PES, so the heavy K atom could pull back the light H atom to initiate the reaction. Similar to the reactive channel, vibrational excitation of the reactant also has a significant effect on the collision-induced dissociation channel.

State-resolved dynamics study of the H + HS reaction on the 3A' and 3A″ states with time-dependent quantum wave packet method.

The quantum dynamics calculations of the H + HS (v = 0, j = 0) reaction on the 3A' and 3A″ potential energy surfaces (PESs) are performed using the reactant coordinate based time-dependent wave packet method. State-averaged and state-resolved results for both channels of the title reaction are presented in the 0.02-1.0 eV collision energy range and compared with those carried out with quasi-classical trajectory (QCT) method. Total integral cross sections (ICSs) for both channels are in excellent agreement with previous quantum mechanical (QM)-Coriolis coupling results while poorly agree with the QCT ICSs of the exchange channel, particularly near the threshold energy region. The product rotational distributions show that for the abstraction channel, the agreement between our QM and the QCT results improves with increasing collision energy. For the exchange channel, our calculations predict colder rotational distributions as compared to those obtained by QCT calculations. Although the QM total differential cross sections (DCSs) are in qualitatively good agreement with the QCT results, the two sets of the state-to-state DCSs with several peaks exhibit great divergences. The origin of the divergences are traced by analyzing the QM DCS for the H + HS (v = 0, j = 0) → H2 (v' = 0, j' = 0) + S reaction on the 3A″ PES at Ec = 1.0 eV. It is discovered that several groups of J partial waves are involved in the reaction and the shape of the DCS is greatly altered by quantum interferences between them.

Could a traumatic epidural hematoma on early computed tomography tell us about its future development? A multi-center retrospective study in China.

Our aim for this study was to quantitatively develop an early epidural hematoma (EDH) natural evolutionary curve and assess association of the most common radiological signs of initially nonsurgical supratentorial EDHs on early computed tomography (CT), in addition to their CT time for EDH enlargement. We retrospectively reviewed pertinent data of supratentorial EDH cases with CT ≤ 6 h postinjury (1997-2013) in three medical institutions in Shanghai. Cases involved were divided into six groups according to their initial CT time postinjury (≤ 1, 1-2, 2-3, 3-4, 4-5, and 5-6 h for groups 1 through 6, respectively). Time of initial CT, EDH-associated fractures, EDH volume, and EDH locations were the focus in the present study. A total of 797 eligible cases were included. The EDH growth curve showed that EDH reached 98.1% of its final stabilized size by volume in 5 ∼ 6 h postinjury. EDH volume and locations on initial CT was greatly associated with subsequent EDH increase ≥ 30 mL with EDH increase requiring surgery when CT time was added. Multi-variate analysis succeeded in determining two risk factors for EDH enlargement ≥ 30 mL and EDH enlargement requiring an operation for EDH cases with an early CT/EDH volume >10 mL on CT performed ≤ 2 h and EDH located at the temporal or temporoparietal region on CT ≤ 1 h post brain injury. Using recursive partitioning analysis, "high-risk" identification criteria were derived to predict EDH enlargement ≥ 30 mL with sensitivity of 90.5% (95% confidence interval [CI], 77.9-96.2), specificity of 60.1% (95% CI, 54.3-65.7), and EDH enlargement requiring surgery with sensitivity of 100.0% (95% CI, 89.9-100.0), and specificity of 59.9% (95% CI, 54.1-65.4). A redo-CT 5 ∼ 6 h post impact for cases at high risk is recommended.

Coriolis coupling effects in O(+)(4S) + H2(X1Σg(+)) → OH (+)(X3Σ(­)) + H(2S) reaction and its isotopic variants: exact time-dependent quantum scattering study.

The time-dependent wave packet quantum method taking into account the Coriolis coupling (CC) has been employed to investigate the dynamics of O(+) + H(2)/D(2)/HD (v(i) = 0, j(i) = 0) reactions based on an accurate potential energy surface [ Martínez et al. J. Chem. Phys. 2004 , 120 , 4705 ]. Through the comparison between the results with and without CC, the pronounced CC effects have been revealed in the title reactions. Moreover, the calculated results with the CC method can well reproduce the data of close-coupling hyperspherical (CCH) exact quantum method. The calculations demonstrate that the CC effects play an important role in the O(+) + H(2) system.

A new rat model for diffuse axonal injury using a combination of linear acceleration and angular acceleration.

Diffuse axonal injury (DAI) is a frequent form of traumatic brain injury, and is usually associated with long-lasting neurological impairments. A new experimental model was developed in the present study to induce DAI in rats by combining low linear and angular accelerations. In most clinical scenarios, DAI is caused by these two forms of acceleration in combination. In the injury-producing facility described here, the rat rotated instantly after it had sustained the impact that produced linear acceleration. Rats rotated rapidly 90 degrees in the coronal plane at a peak angular acceleration of 137 +/- 12 krad/sec(2) with a duration of 33.7 +/- 1.2 msec. The linear acceleration was applied to the rat's head by dropping a 450 g weight from a height of 0.9 m. Rats exposed to the combined accelerations took significantly longer to regain consciousness (11.9 +/- 3.6 min) than control rats (p < 0.01) or rats subjected to purely angular or linear acceleration (p < 0.01). Although macroscopic damage was observed in all brain-injured animals, axonal damage and hemorrhagic tissue tears were only noted in the animals sustaining the combined accelerations. All rats survived the purely linear or angular acceleration, whereas the mortality rate reached 21.7% following the combined accelerations. These results show that this model is capable of reproducing the major histological and neurological changes that are associated with DAI, and that the combination of low linear and angular accelerations can produce non-linear and synergistic effects to induce moderate/severe DAI.

Sinus pericranii in the right frontal region and thrombosis.

Sinus pericranii is a rare vascular anomaly in which an abnormal communication exists between the extracranial venous system and the underlying dural venous sinus via the diploe of the skull. We describe a case of a spontaneous thrombosis of the sinus pericranii which was located in the right frontal region and presented as a focal, leathery, and noncompressible mass distinguished in character from the typical manifestation of sinus pericranii. In this case, CT, DSA, MRI, MR venography (MRV), and pathologic examination were performed. The CT showed the bone depression in the skull and the MRI demonstrated the mass, but they were not sufficiently sensitive to detect the thrombus. Pathologic examination and MRV were helpful in depicting the thrombus. She underwent a surgical resection, and at the 5-month follow-up there was no evidence of recurrence.

Giant intradiploic epidermoid cyst of the occipital bone.

Epidermoid cysts are uncommon, benign and slow-growing lesions. They often reach an enormous size without producing neurologic symptoms. We describe a 35-year-old female who had a giant intradiploic epidermoid cyst of the occipital bone. She underwent posterior cranial fossa tumor resection. Pathology confirmed epidermoid cyst. There was no recurrence at 13-month follow-up. Total removal of these cysts and repeated washing of the cavity with 0.9% saline may prevent recurrence and aseptic meningitis.

c-Met-targeted RNA interference inhibits growth and metastasis of glioma U251 cells in vitro.

Angiogenesis plays an essential role in tumor growth and metastasis and is a promising target for cancer therapy. c-Met, a receptor tyrosine kinase, and its ligand, hepatocyte growth factor (HGF), are critical in cellular proliferation, motility, invasion, and angiogenesis. The present study was designed to determine the role of c-Met in growth and metastasis of glioma U251 cells using RNA interference (RNAi) technology in vitro. We constructed three kinds of shRNA expression vectors aiming at the c-Met gene, then transfected them into glioma U251 cells by lipofectamine(TM) 2000. The level of c-Met mRNA was investigated by real-time polymerse chain reaction (RT-PCR). The protein expression of c-Met was observed by immunofluoresence staining and western blotting. U251 cell growth and adherence was detected by methyl thiazole tetrazolium assay. The apoptosis of U251 cells was examined with a flow cytometer. The adherence, invasion, and in vitro angiogenesis assays of U251 cells were done. We got three kinds of c-Met specific shRNA expression vectors which could efficiently inhibit the growth and metastasis of U251 cells and the expression of c-Met in U251 cells. RT-PCR, immunofluoresence staining and western blotting showed that inhibition rate for c-Met expression was up to 90%, 79% and 85%, respectively. The expression of c-Met can be inhibited by RNA interference in U251 cells, which can inhibit the growth and metastasis of U251 cell and induce cell apoptosis. These results indicate that RNAi of c-Met can be an effective antiangiogenic strategy for glioma.