A novel method for septal reduction therapy by three-dimensional guided transvenous intraseptal pulsed-field ablation

BACKGROUND

Pulsed-field ablation (PFA) is a nonthermal method for achieving selective cell death with little inflammation response. However, there are no reports of PFA for septal reduction therapy (SRT).

OBJECTIVE

The purpose of this study was to investigate the effectiveness and safety of PFA for SRT.

METHODS

A novel transvenous intraseptal PFA method with 3-dimensional (3D) guidance was introduced in Yorkshire pigs. Electrocardiographic parameters, transthoracic echocardiography, and histopathology were used to evaluated.

RESULTS

The maximum injury diameter of intramyocardial PFA increased with electric field intensity. After PFA, bipolar electrogram amplitude and pacing threshold measured by the PFA electrodes significantly decreased (F = 6.945, P = .007) or increased (F = 5.842, P = .024), respectively. In the ablated septal region, motion amplitude and systolic wall thickening rate significantly decreased and remained at low levels (motion amplitude: F = 20.793, P = .000; systolic wall thickening rate: F = 14.343, P = .000); however, septal thickness did not significantly change after PFA (F = 1.503, P = .248). Histologic examination showed specific cardiomyocyte death with gradually increased hyperchromatic cytoplasm and nuclear pyknosis, without obvious inflammatory cell infiltration in acute phase. TUNEL stain for fragmented DNA showed extensively positive in the ablation region 24 hours after PFA. During PFA, no sustained ventricular arrhythmia or atrioventricular conduction block occurred.

CONCLUSION

A novel intraseptal PFA method with 3D guidance was described. Intraseptal PFA resulted in effective myocardial injury and local hypokinesis without significant acute edema. Histologic examination showed widely programmed cardiomyocyte death with little inflammatory cell infiltration.

Complete chloroplast genomes of eight Artemisia species: Comparative analysis, molecular identification, and phylogenetic analysis

Artemisia L. is the largest genus in the Asteraceae, and well known for its high medicinal value. The morphological features of Artemisia species are similar, making taxonomic identification and evolutionary research difficult. We sequenced chloroplast genomes of eight Artemisia species, all of which are common adulterants of A. argyi. We used novel genetic data and compared these data to the published A. argyi chloroplast genome in to develop molecular markers for species identification and reconstructing phylogenetic relationships between Artemisia species. The eight chloroplast sequences were highly similar in gene order, content, and structure, encoding a total of 114 genes (82 protein-coding genes, 28 tRNAs, and four rRNAs). All species harboured similar repeat sequences and simple sequence repeats (SSRs), ranging from 47 to 49 and 38 to 40 repeats, respectively. In addition, we identified five hypervariable regions (rpl32-trnL, rps16-trnQ, petN-psbM, trnE-rpoB, and atpA-trnR) and ten variable coding genes (ycf1, psbG, rpl36, psaC, psaI, accD, psbT, ndhD, ndhE, and psbH), which can be used to develop chloroplast molecular markers. Finally, phylogenetic reconstructions based on six datasets produced similar topologies, revealing A. argyi is closely related to species often found as adulterants, as expected. Our research provides valuable new information on the evolution and phylogenetic relationships between Artemisia chloroplast genomes and identifies valuable molecular makers to distinguish it from closely related species.

Treatment of auricular pseudocysts using enhanced negative drainage: a prospective study of 21 cases

OBJECTIVE

Auricular pseudocysts are rare, painless, benign intracartilaginous cysts of the auricle that are not lined by epithelium and have no known aetiology.

METHOD

This was a prospective study conducted in an ENT department from January 2020 to June 2022. In 21 patients, complete aspiration of the pseudocyst with enhanced negative drainage was performed. They were followed for a minimum of six months.

RESULTS

All patients completely responded to the negative drainage treatment. No cases of recurrence or obvious deformities were observed.

CONCLUSION

Aspiration with intensified negative drainage was associated with a positive response in patients with auricular pseudocysts. Complete resolution of the swelling can be achieved without any serious complications. Thus, it appears to be a simple and effective method for managing the condition.

Immediate implant placement for chronic peri-apical periodontitis in the molar region: a randomised controlled trial

The aim of this study was to evaluate the feasibility of immediate implantation for chronic peri-apical periodontitis in the molar region. Seventy-four molars were selected and allocated randomly to two groups. The experimental group (n = 38) received immediate implantation by flap surgery and the control group (n = 36) received delayed implantation. CBCT was performed immediately after surgery (T1) and 12 months after the permanent repair (T3). The implant survival rate at T3 was 100% in both groups. There was no significant difference in buccal or lingual vertical marginal bone loss between the groups (P = 0.515, P = 0.736). However, the buccal horizontal margin bone loss was significantly greater in the experimental group: 0.98 ± 0.34 mm vs 0.77 ± 0.27 mm in the control group (P = 0.003). In the experimental group, the highest point of buccal and lingual implant-bone contact increased at T3. The buccal and lingual jump gap widths were 3.21 ± 1.10 mm and 2.92 ± 1.01 mm at T1, and CBCT showed no jump gap around the implants at T3. The clinical outcomes showed immediate implantation to be feasible for chronic peri-apical periodontitis in the molar region.

Improved temporal resolution in ultrafast electron diffraction measurements through THz compression and time-stamping

We present an experimental demonstration of ultrafast electron diffraction (UED) with THz-driven electron bunch compression and time-stamping that enables UED probes with improved temporal resolution. Through THz-driven longitudinal bunch compression, a compression factor of approximately four is achieved. Moreover, the time-of-arrival jitter between the compressed electron bunch and a pump laser pulse is suppressed by a factor of three. Simultaneously, the THz interaction imparts a transverse spatiotemporal correlation on the electron distribution, which we utilize to further enhance the precision of time-resolved UED measurements. We use this technique to probe single-crystal gold nanofilms and reveal transient oscillations in the THz near fields with a temporal resolution down to 50 fs. These oscillations were previously beyond reach in the absence of THz compression and time-stamping.

Monitoring the Evolution of Relative Product Populations at Early Times during a Photochemical Reaction

Identifying multiple rival reaction products and transient species formed during ultrafast photochemical reactions and determining their time-evolving relative populations are key steps toward understanding and predicting photochemical outcomes. Yet, most contemporary ultrafast studies struggle with clearly identifying and quantifying competing molecular structures/species among the emerging reaction products. Here, we show that mega-electronvolt ultrafast electron diffraction in combination with ab initio molecular dynamics calculations offer a powerful route to determining time-resolved populations of the various isomeric products formed after UV (266 nm) excitation of the five-membered heterocyclic molecule 2(5H)-thiophenone. This strategy provides experimental validation of the predicted high (∼50%) yield of an episulfide isomer containing a strained three-membered ring within ∼1 ps of photoexcitation and highlights the rapidity of interconversion between the rival highly vibrationally excited photoproducts in their ground electronic state.

Hidden phonon highways promote photoinduced interlayer energy transfer in twisted transition metal dichalcogenide heterostructures

Vertically stacked van der Waals (vdW) heterostructures exhibit unique electronic, optical, and thermal properties that can be manipulated by twist-angle engineering. However, the weak phononic coupling at a bilayer interface imposes a fundamental thermal bottleneck for future two-dimensional devices. Using ultrafast electron diffraction, we directly investigated photoinduced nonequilibrium phonon dynamics in MoS2/WS2 at 4° twist angle and WSe2/MoSe2 heterobilayers with twist angles of 7°, 16°, and 25°. We identified an interlayer heat transfer channel with a characteristic timescale of ~20 picoseconds, about one order of magnitude faster than molecular dynamics simulations assuming initial intralayer thermalization. Atomistic calculations involving phonon-phonon scattering suggest that this process originates from the nonthermal phonon population following the initial interlayer charge transfer and scattering. Our findings present an avenue for thermal management in vdW heterostructures by tailoring nonequilibrium phonon populations.

Acute and long-term outcomes of pulmonary vein isolation and left atrial substrate modification for non-paroxysmal atrial fibrillation: a non-randomized trial

Background

The long-term success rate of nonparoxysmal atrial fibrillation (AF) treated with pulmonary vein isolation (PVI) alone is not ideal. This may indicate atrial fibrosis as a major cause of recurrence. Therefore, the aim of this study is to investigate the efficacy of left atrial substrate modification (LASM) by targeting low-voltage area.

Methods

A total of 157 consecutive patients with drug-refractory nonparoxysmal AF who underwent radiofrequency ablation during hospitalization in the Third People's Hospital of Chengdu from April 2017 to August 2021 were prospectively included. Stepwise ablation was performed in two different orders: LASM first (n=53) and PVI first (n=104) group. All patients underwent ablation during AF, and the procedural endpoint was AF termination during ablation. In the LASM first group, LASM was performed first and if AF was terminated, PVI was not performed. Similarly, in the PVI first groups, LASM was performed if AF was not terminated. The primary outcome were AF termination and freedom from AF. The secondary outcome was adverse events. Cox regression analysis was used to define predictors of AF termination, and Kaplan-Meier analysis was used to assess differences between groups in AF freedom.

Results

The baseline characteristics of the two groups were similar. At a median follow-up of 16 months, the 112 patients (39 in LASM first group and 73 in PVI first group) with AF termination had a higher success rate than the 45 patients who had no AF termination (78.6% vs. 57.8%; P<0.01). The AF termination rate (24/53, 45.3% vs. 12/104, 11.5%; P<0.01) and AF freedom (20/24, 83.3% vs. 7/12, 58.3%; P=0.13) by LASM alone was higher than PVI alone. There were 3 cases of heart failure and 1 case of stroke (4/53) in the LASM first group, and 1 case of pericardial tamponade, 5 cases of heart failure and 1 case of stroke (7/104) in the LASM first group (7.5% vs. 6.7%; P>0.05).

Conclusions

LASM provides higher immediate success and a slightly better long-term success rate compared to PVI. Patients who terminated AF were more likely to have AF freedom than those who did not. AF termination during procedure may improve symptoms and reduce hospitalization.

Multi-scale time-resolved electron diffraction: A case study in moiré materials

Ultrafast-optical-pump - structural-probe measurements, including ultrafast electron and x-ray scattering, provide direct experimental access to the fundamental timescales of atomic motion, and are thus foundational techniques for studying matter out of equilibrium. High-performance detectors are needed in scattering experiments to obtain maximum scientific value from every probe particle. We deploy a hybrid pixel array direct electron detector to perform ultrafast electron diffraction experiments on a WSe2/MoSe2 2D heterobilayer, resolving the weak features of diffuse scattering and moiré superlattice structure without saturating the zero order peak. Enabled by the detector's high frame rate, we show that a chopping technique provides diffraction difference images with signal-to-noise at the shot noise limit. Finally, we demonstrate that a fast detector frame rate coupled with a high repetition rate probe can provide continuous time resolution from femtoseconds to seconds, enabling us to perform a scanning ultrafast electron diffraction experiment that maps thermal transport in WSe2/MoSe2 and resolves distinct diffusion mechanisms in space and time.

[Survey on the cognition of the "undetectable equals untransmittable" concept among HIV-infected men who have sex with men receiving antiviral treatment]

Objective: To explore the cognition of the "undetectable equals untransmittable" ("U=U") concept and associated factors among HIV-infected men who have sex with men (MSM) receiving antiviral treatment (ART) in Shenzhen, and provide evidence for designing promotion and advocacy strategies for the "U=U" concept. Methods: We recruited HIV-infected MSM receiving ART using convenient sampling method combined with routine follow-up in Shenzhen through conducting observational survey. The sample size was estimated to be 475. A questionnaire was administered to collect socio-demographic characteristics, sexual behaviors, ART, viral load testing and the cognition towards "U=U" in HIV-infected MSM. Logistic regression was used to access factors associated with acceptance of "U=U". Results: A total of 490 HIV-infected MSM receiving ART were recruited. Of whom, 60.2% (295/490) were aware of "U=U" and 50.6% (248/490) accepted "U=U". Multiple logistic regression showed that participants who had an educational level of college or above (aOR=1.76,95%CI: 1.12-2.75) were more likely to accept "U=U". Those who had no local residency (aOR=0.51,95%CI: 0.29-0.92), had viral load >0 copies/ml in the last testing (aOR=0.61,95%CI: 0.38-0.98) and were unaware of "U=U" (aOR=0.13, 95%CI: 0.09-0.21), were less likely to accept "U=U". Conclusions: HIV-infected MSM receiving ART had a low cognition level of "U=U" in Shenzhen. Promotion and advocacy on this concept through healthcare workers should be enhanced in combination with routine follow-up in order to improve their ART adherence and outcome of treatment. Furthermore, developing related guidelines on "U=U" according to the characteristics of HIV-infected individuals is warranted to improve the normalization of promotion and advocacy on "U=U".

New Data-Driven Gated (DDG) PET/CT for Radiation Treatment Planning of NSCLC

PURPOSE/OBJECTIVE(S)

PET/CT for RT simulation of NSCLC is typically conducted in two separate imaging sessions of gated 4D-CT in radiation oncology and fusion with non-gated PET/CT in diagnostic imaging, making treatment response assessment (TRA) with PET/CT and radiation treatment planning (RTP) challenging. To remedy this short-coming, we designed a new data-driven gated (DDG) PET/CT, based on the self-gated PET and self-gated CT data to derive the gated PET/CT data free of tumor blurring and misregistration artifacts without any respiratory monitoring device (ease of use and cost reduction). The new DDG PET/CT also provides the important 4D-CT information of end-inspiratory (EI), end-expiratory (EE), maximum-intensity-projection (MIP) and average-intensity-projection (AIP) CT's. The total imaging time is < 15 min, which makes DDG PET/CT simulation in a single session without any respiratory monitoring device possible.

MATERIALS/METHODS

Acquisition is standard PET/CT imaging protocol followed by a cine CT imaging of the tumor area. We utilized the commercial DDG PET from GE Discovery PET/CT and designed a new DDG CT for attenuation correction of the DDG PET for reduction of tumor motion and mis-registration. The AIP and MIP images were from the average and maximum pixel values of the cine CT images, respectively. The cine CT images with the largest and smallest average CT number in the lung region were identified as the EE and EI CT images, respectively. For the image slices without any lung region present, the largest and smallest expansions of the body outline contour were selected to be the EE and EI CT phases, respectively. The AIP and EE CT images were used for attenuation correction of the PET and DDG PET data, respectively. Both DDG PET/CT and 4D-CT of (EI, EE, AIP and MIP) are for RT simulation of NSCLC. 38 4D-CT patient data sets were compared at the EE and EI phases between our DDG CT and 4D-CT to demonstrate the applicability of the newly designed DDG CT.

RESULTS

A prototype software on a Dell PC of i5-6500 CPU has been successfully developed to enable DDG PET/CT and 4D-CT on seven GE Discovery PET/CT scanners. The operating system was Ubuntu and the computer language was Python. In the EE phase, the images selected by DDG CT and 4D CT were identical 62.5±21.6% of the time. In the EI phase, the images selected by DDG CT and 4D CT were identical 68.2±18.9% of the time. Inspection of the EE and EI phases of DDG CT and 50% and 0% of 4D-CT demonstrated both data sets of DDG CT and 4D CT were almost identical.

CONCLUSION

A new DDG PET/CT and 4D-CT in a single imaging session without any hardware gating has been developed for TRA and RTP of NSCLC. The utility is available on the network and it enables all PET/CT scanners on the network for TRA and RTP. The new DDG CT provides the benefits of 4D-CT without any requirement of external hardware gating and make possible DDG PET/CT free of tumor motion and misregistration artifacts.

The Incidence and Prognosis Value of Perineural Invasion in Rectal Carcinoma: From Meta-Analyses and Real-World Clinical Pathological Features

AIMS

Perineural invasion (PNI) is a special type of metastasis of several cancers and has been reported as being a factor for poor prognosis in colorectal carcinoma. However, investigations of PNI in only rectal cancer and a comprehensive analysis combining meta-analyses with real-world case studies remain lacking.

MATERIALS AND METHODS

First, articles from 2000 to 2020 concerning the relationship between PNI and rectal cancer prognoses and clinical features were meta-analysed. Subsequently, we carried out a retrospective analysis of 312 rectal cancer cases that underwent radical surgery in the real world. The incidence of PNI and the relationship between PNI and prognosis, as well as clinicopathological factors, were investigated.

RESULTS

The incidence of PNI was 23.09% and 33.01% in the meta-analysis and clinical cases, respectively. PNI occurred as early as stage I (2.94%). Moreover, neoadjuvant therapy significantly reduced the PNI-positive rate (20.34% versus 26.54%). Both meta-analysis and real-world clinical case studies suggested that PNI-positive patients had poorer prognoses than PNI-negative patients. We established an effective risk model consisting of T stage, differentiation and lymphovascular invasion to predict PNI in rectal cancer.

CONCLUSION

PNI is a poor prognostic factor for rectal cancer and could occur even in stage I. Additionally, neoadjuvant therapy could sufficiently reduce the PNI-positive rate. T stage, lymphovascular invasion and differentiation grade were independent risk factors for PNI and the risk model that included these factors could predict the probability of PNI.

Evaluating the Utility of Traditional Bowel Dose Constraints when Treating Abdominal and Pelvic Sarcomas with Preoperative Radiation Therapy

PURPOSE/OBJECTIVE(S)

Abdominopelvic soft tissue sarcomas (AP-STS) are selectively treated with preoperative radiation therapy (RT) followed by surgery. Due to their rarity, most bowel dose constraints are extrapolated from dosimetric studies for other abdominal or pelvic malignancies where concurrent chemotherapy is often given in addition to RT. We sought to investigate associations between dosimetric bowel constraints and the risk for developing acute and long-term toxicities in patients who received preoperative RT for AP-STS.

MATERIALS/METHODS

We performed a retrospective review of patients treated at a tertiary cancer center for non-metastatic AP-STS between 2005 and 2020. Dosimetric parameters for the "bowel bag" organ at risk structure were extracted for each patient. Chi-Square or Fisher's Exact Test, where appropriate, was utilized to compare the proportion of patients who exceeded constraints to the bowel bag contour as per the consensus RT retroperitoneal sarcoma guidelines, and the development of acute and long-term toxicities.

RESULTS

We identified 39 patients with available dosimetric data. The median follow-up was 34 months (IQR 20-47). Approximately half of the tumors were located in the pelvis (n = 20, 51%), and the majority were treated with IMRT/VMAT (n = 35, 90%). 31 patients (80%) presented with de novo disease, and 20% (n = 8) were recurrent presentations but had not received prior RT. The most common histology was leiomyosarcoma (n = 15, 38%), followed by de-differentiated liposarcoma (n = 8, 21%). The median bowel max dose (defined as D0.1cc) was 5309cGy [IQR 5262-5830]. Thirteen patients (33%) exceeded the volumetric V15 Gy <830cm3 bowel bag constraint, and 18 (46%) exceeded the V45 Gy ≤ 195cm3 bowel bag constraint. Overall, 17 patients (44%) had acute grade 1 diarrhea, and 11 (28%) had grade 1-2 nausea. Five patients (13%) had long-term radiation-related toxicities, including 1 patient who developed an enterocutaneous fistula. There was no association between exceeding V15 Gy>830 cm3 (p = 0.31) or V45 Gy≥195cm3 (p = 0.65) bowel bag constraints and developing a long-term RT toxicity. Similarly, exceeding V15 Gy>830 cm3 or V45 Gy≥195cm3 did not lead to increased risks of developing acute diarrhea, nausea, or any other acute RT toxicity (all p>0.05).

CONCLUSION

Traditional volumetric bowel bag dose constraints are frequently exceeded given the large size of AP-STS at presentation and thus the large RT target volumes. Despite a significant proportion of patients exceeding these constraints, these data suggest that RT is overall well-tolerated, and the risk of developing toxicities does not correlate with traditional bowel bag volumetric constraints. There are ongoing efforts to substantially expand this cohort for further investigation into the relationship between dosimetric data and bowel toxicities in order to identify more predictive bowel constraints that can be used during treatment planning of AP-STS.

[Differences in biochemical indexes and AIDS-related complications at baseline in HIV- infected patients with different levels of immune reconstitution after antiretroviral therapy]

Objective: To observe the differences in biochemical indexes and AIDS-related complications at baseline in HIV-infected patients with different levels of immune reconstitution to antiretroviral therapy (ART). Methods: The subjects were treat-naïve adult HIV-infected patients who were followed up for more than 24 months in the Guangzhou Eighth People's Hospital affiliated infection clinic at Guangzhou Medical University from January 2010 to December 2017. CD4+ T lymphocyte count at baseline at <200, 200-350, and >350 cells/µl levels were divided into poor, partial, and good immune reconstitution groups. The Kruskal-Wallis H and chi-square tests were used to analyze the differences in baseline sociodemographic characteristics, biochemical indexes, and AIDS-related complications among different groups. The SPSS 20.0 software was used for statistical analysis. Results: Among the 3 900 HIV-infected individuals, 385 cases (9.9%), 1 206 cases (30.9%), and 2 309 cases (59.2%) were grouped into poor, partial and good immune reconstitution groups, respectively. The baseline biochemical indexes of leukocyte, platelet, hemoglobin, TG, TC, FPG, AST, ALT and total bilirubin in the poor immune reconstitution group were significantly different from those in the good immune reconstitution group (all P<0.05). The proportion of AIDS-related complications at baseline in the poor immune reconstitution group, such as tuberculosis, pneumocystis yeli pneumonia, disseminated mycosis, esophageal candidiasis, extrapulmonary tuberculosis, dermatitis, oral candidiasis, oral mucous leukoplakia, continuous diarrhea for more than 1 month and continuous or intermittent fever for more than 1 month, was significantly higher than that in the good immune reconstitution group (all P<0.05). Conclusions: The biochemical indexes and AIDS-related complications in HIV-infected patients with different levels of immune reconstitution were significantly different at baseline. Attention should be paid to monitoring abnormal biomedical indicators and AIDS-related complications at baseline.

Spin-mediated shear oscillators in a van der Waals antiferromagnet

Understanding how microscopic spin configuration gives rise to exotic properties at the macroscopic length scale has long been pursued in magnetic materials1-5. One seminal example is the Einstein-de Haas effect in ferromagnets1,6,7, in which angular momentum of spins can be converted into mechanical rotation of an entire object. However, for antiferromagnets without net magnetic moment, how spin ordering couples to macroscopic movement remains elusive. Here we observed a seesaw-like rotation of reciprocal lattice peaks of an antiferromagnetic nanolayer film, whose gigahertz structural resonance exhibits more than an order-of-magnitude amplification after cooling below the Néel temperature. Using a suite of ultrafast diffraction and microscopy techniques, we directly visualize this spin-driven rotation in reciprocal space at the nanoscale. This motion corresponds to interlayer shear in real space, in which individual micro-patches of the film behave as coherent oscillators that are phase-locked and shear along the same in-plane axis. Using time-resolved optical polarimetry, we further show that the enhanced mechanical response strongly correlates with ultrafast demagnetization, which releases elastic energy stored in local strain gradients to drive the oscillators. Our work not only offers the first microscopic view of spin-mediated mechanical motion of an antiferromagnet but it also identifies a new route towards realizing high-frequency resonators8,9 up to the millimetre band, so the capability of controlling magnetic states on the ultrafast timescale10-13 can be readily transferred to engineering the mechanical properties of nanodevices.

Higher allochthonous organic carbon increases polycyclic aromatic hydrocarbon concentration whereas fossil fuel combustion alters the composition: Evidence from a eutrophic plateau lake in southwest China

Understanding the source of polycyclic aromatic hydrocarbons (PAHs) is crucial for determining their structural, degradational, and burial characteristics in lake sediments. Here, we used a sediment core to determine the changing sources and burial characteristics of 16 PAHs from Dianchi Lake, southwest China. The ∑₁₆PAH concentrations ranged from 105.10 to 1248.05 ng g^-1 (448.97 ± 351.25 ng g^-1), exhibiting a sharp increase since 1976. Our results showed that the depositional flux of PAHs has increased by approximately 3.72 times over the past 114 years (1895-2009). The C/N ratio, stable isotopes (δ¹³C_org and δ¹⁵N), and n-alkanes data all indicated that allochthonous contributors of organic carbon have substantially increased since the 1970s, playing an important role in the increase in sedimentary PAHs. Positive matrix factorization indicated that petrogenic sources, coal and biomass combustion, and traffic emissions were the main sources of PAHs. The relationships between PAHs from different sources and total organic carbon (TOC) varied with the sorption characteristics. The effect of TOC on the absorption of high-molecular-weight aromatic PAHs from fossil fuels was significant. A higher risk of lake eutrophication is accompanied by higher allochthonous organic matter imports, which might stimulate an increase in sedimentary PAHs through algal biomass blooms.

Rehybridization dynamics into the pericyclic minimum of an electrocyclic reaction imaged in real-time

Electrocyclic reactions are characterized by the concerted formation and cleavage of both σ and π bonds through a cyclic structure. This structure is known as a pericyclic transition state for thermal reactions and a pericyclic minimum in the excited state for photochemical reactions. However, the structure of the pericyclic geometry has yet to be observed experimentally. We use a combination of ultrafast electron diffraction and excited state wavepacket simulations to image structural dynamics through the pericyclic minimum of a photochemical electrocyclic ring-opening reaction in the molecule α-terpinene. The structural motion into the pericyclic minimum is dominated by rehybridization of two carbon atoms, which is required for the transformation from two to three conjugated π bonds. The σ bond dissociation largely happens after internal conversion from the pericyclic minimum to the electronic ground state. These findings may be transferrable to electrocyclic reactions in general.

SGLT2 inhibitors for prevention of primary and secondary cardiovascular outcomes: A meta-analysis of randomized controlled trials

BACKGROUND

Many clinical studies have shown that sodium-glucose cotransporter 2 inhibitors (SGLT2i) reduce cardiovascular risks, such as heart failure, myocardial infarction and cardiovascular death.

OBJECTIVE

To investigate the use of SGLT2i for the prevention of primary and secondary cardiovascular outcomes.

METHODS

Pubmed, Embase and Cochrane libraries databases were searched and meta-analysis was performed using Revman 5.4.

RESULTS

Eleven studies with a total of 34,058 cases were analyzed. SGLT2i significantly reduced major adverse cardiovascular events (MACE) in patients with prior myocardial infarction (MI) (OR 0.83, 95% CI 0.73-0.94, p = 0.004), no prior MI (OR 0. 82, 95% CI 0.74-0.90, p<0.0001), prior coronary atherosclerotic disease (CAD) (OR 0.82, 95% CI 0.73-0.93, p = 0.001) and no prior CAD (OR 0.82, 95% CI 0.76-0.91, p = 0.0002) compared with placebo. In addition, SGLT2i significantly reduced hospitalization due to heart failure (HF) in patients with prior MI (OR 0.69, 95% CI 0.55-0.87, p = 0.001), no prior MI (OR 0.63, 95% CI 0.55-0. 72, p<0.00001), prior CAD (OR 0.65, 95% CI 0.53-0.79, p<0.0001) and no prior CAD (OR 0.65, 95% CI 0.56-0.75, p<0.00001) compared with placebo. SGLT2i reduced cardiovascular mortality and all-cause mortality events. MI (OR 0.79, 95% CI 0.70-0.88, p<0.0001), renal damage (OR 0.73, 95% CI 0.58-0.91, p = 0.004), all-cause hospitalization (OR 0.89, 95% CI 0.83-0.96, p = 0.002), systolic and diastolic blood pressure were all significantly reduced in patients receiving SGLT2i.

CONCLUSION

SGLT2i was effective in prevention of primary and secondary cardiovascular outcomes.

Ultrafast Optomechanical Strain in Layered GeS

Strong coupling between light and mechanical strain forms the foundation for next-generation optical micro- and nano-electromechanical systems. Such optomechanical responses in two-dimensional materials present novel types of functionalities arising from the weak van der Waals bond between atomic layers. Here, by using structure-sensitive megaelectronvolt ultrafast electron diffraction, we report the experimental observation of optically driven ultrafast in-plane strain in the layered group IV monochalcogenide germanium sulfide (GeS). Surprisingly, the photoinduced structural deformation exhibits strain amplitudes of order 0.1% with a 10 ps fast response time and a significant in-plane anisotropy between zigzag and armchair crystallographic directions. Rather than arising due to heating, experimental and theoretical investigations suggest deformation potentials caused by electronic density redistribution and converse piezoelectric effects generated by photoinduced electric fields are the dominant contributors to the observed dynamic anisotropic strains. Our observations define new avenues for ultrafast optomechanical control and strain engineering within functional devices.

Panoramic Mapping of Phonon Transport from Ultrafast Electron Diffraction and Scientific Machine Learning

One central challenge in understanding phonon thermal transport is a lack of experimental tools to investigate frequency-resolved phonon transport. Although recent advances in computation lead to frequency-resolved information, it is hindered by unknown defects in bulk regions and at interfaces. Here, a framework that can uncover microscopic phonon transport information in heterostructures is presented, integrating state-of-the-art ultrafast electron diffraction (UED) with advanced scientific machine learning (SciML). Taking advantage of the dual temporal and reciprocal-space resolution in UED, and the ability of SciML to solve inverse problems involving O ( 10 3 ) $\mathcal{O}({10^3})$ coupled Boltzmann transport equations, the frequency-dependent interfacial transmittance and frequency-dependent relaxation times of the heterostructure from the diffraction patterns are reliably recovered. The framework is applied to experimental Au/Si UED data, and a transport pattern beyond the diffuse mismatch model is revealed, which further enables a direct reconstruction of real-space, real-time, frequency-resolved phonon dynamics across the interface. The work provides a new pathway to probe interfacial phonon transport mechanisms with unprecedented details.

Effect of Statins on Major Adverse Cardiovascular Events in Patients with Coronary Artery Spasm: A Meta-Analysis of the Asia Region

Background

Whether statins can reduce major cardiovascular adverse events (MACE) in patients with coronary artery spasm (CAS) is controversial. And most of the relevant research to date has been conducted in Asia.

Methods

We systematically searched electronic databases for studies on the effect of statins on MACE in patients with CAS in Asia and published up to September 2022. We included data on MACE in a statin therapy patient group and a no-statin therapy control group. We then evaluated the effect of statin therapy on MACE in patients with CAS in Asia by meta-analysis and trial sequential analysis (TSA). All statistical analyses were performed using Stata 16.0 software and TSA software.

Results

A total of 10 studies (n = 9333 patients) were included in the final analysis. Meta-analysis showed that the use of statins had a significant effect on MACE in CAS patients (with RR, 0.70; 95% CI, 0.49-0.99), and the sensitivity analysis further confirmed this finding. Subgroup analysis suggested that the correlation between statin therapy and reduced MACE endpoint was stronger in Japanese patients and patients followed up for more than 4 years. But our TSA results indicated that the available samples were insufficient and further research is needed.

Conclusions

Our meta-analysis suggests that statin therapy can reduce MACE in patients with CAS in Asia, and the correlation between the two was stronger in Japanese patients and patients followed up for more than 4 years.

Sediment record in pollution, toxicity risk, and source assignment of polycyclic aromatic hydrocarbons (PAHs) in Erhai Lake, Southwest China

Surface sediments and sediment core had been collected from Erhai Lake, Southwest China to study the concentrations, toxicity risks, and sources of polycyclic aromatic hydrocarbons (PAHs). The average concentrations of Σ₁₆PAHs, seven carcinogenic PAHs (carPAHs), and carcinogenic toxic equivalents (TEQ^car) in the surface sediments and sediment core were 1634.50 ± 488.56 ng g^-1 and 436.72 ± 128.17 ng g^-1, 67.18-293.65 ng g^-1 and 91.07-265.90 ng g^-1, and 34.89 ± 13.17 ng g^-1 and 36.99 ± 7.52 ng g^-1, respectively. The Σ₁₆PAHs and carPAHs concentrations in surface sediments were higher in the southern lake. The Σ₁₆PAHs and TEQ^car in the sediment core peaked in the 2010s and 1980s. The spatiotemporal variations in TEQ^car and carPAHs were similar. Positive matrix factorization revealed that traffic emissions contributed 35.71 % of the TEQ^car, whereas coal and biomass combustion contributed 12.89 % in the surface sediments. The contribution of gasoline and fossil fuel to TEQ^car significantly increased from 19.2 % (1890s) to 66.5 % (1990s), that of benz[a]pyrene (coal combustion) decreased, and those of benz[b]fluoranthene and indeno[1,2,3-cd]pyrene (petroleum combustion and traffic emissions) increased from 1.92 % to 3.93 % and from 1.54 % to 2.52 % in the sediment cores, respectively, owing to changes in energy consumption.

Hierarchical domain structures associated with oxygen octahedra tilting patterns in lead-free (Bi1/2Na1/2)TiO3

Hierarchical domain structures associated with oxygen octahedra tilting patterns were observed in lead-free (Bi_1/2Na_1/2)TiO₃ceramics using aberration-corrected high-resolution transmission electron microscopy (HRTEM). Three types of domains are induced by distinct mechanisms: the 'orientation-domain' is induced at micrometer scale formed by different tilting orientations of the oxygen octahedra, the 'meso-chemical-domain' occurs at a few tens of nanometer scale by chemical composition variation on the A-site in the ABO₃perovskite structure, and the 'nano-cluster-region' runs across several unit-cells with apparent A-site cation segregation with oxygen vacancies clustering around Na cations. Based on HRTEM amplitude contrast imaging (ACI), the correlation between the oxygen octahedral tilting pattern and compositional non-stoichiometry was established. The role of the hierarchical domain structure associated with the tilting patterns of the oxygen octahedra on the ferroelectric behavior of (Bi_1/2Na_1/2)TiO₃is also discussed.

[Clinical effect and analysis of exercise treatment for temporomandibular joint osteoarthritis]

Objective: To explore the clinical efficacy of (stomatognathic system functional exercise(SSFE) in the treatment of temporomandibular joint osteoarthritis (TMJOA), and to provide reference for the clinical treatment of TMJOA. Methods: Choose between January 2020 and June 2020 in the Affiliated Hospital of Qingdao University of Temporomandibular Disorder (TMD) Clinics, pain in the temporomandibular joint (TMJ), limited openings for complained of symptoms of TMD patients, diagnosed by clinical examination and cone beam CT (CBCT) examination of TMJOA patients 60 patients (64 joints), including 20 males and 45 females, the age was (42.6±2.5) years (33-47 years old). The patients were randomly divided into the experimental group (30 cases, 34 joints) and the control group (30 cases, 30 joints) according to the odd and even numbers of their treatment numbers. The experimental group was treated with SSFE method. The control group was treated with maxillary full dentition occlusal splint. Visual analogue score (VAS), natural mouth opening and maximal mouth opening (MMO) of each patient in each group were recorded at initial diagnosis, 2 weeks, 3 and 6 months after treatment, and CBCT imaging was compared for the changes of condylar bone at initial diagnosis, 3 and 6 months after treatment. Results: VAS values of the experimental groups were (2.90±1.42), (0.90±0.37), (0.87±0.23) at 2 weeks, 3 and 6 months after treatment, respectively. The VAS values of the control group were (4.57±1.94), (4.17±2.09), (3.73±2.21), respectively. The VAS score of the experimental group was significantly lower than that of the control group (F=42.93, P<0.001). Before SSFE treatment, all the patients in the experimental group had different degrees of restricted opening and characteristic abnormal opening and closing pattern. Two weeks after SSFE treatment, the opening degree of the patients was (37.69±2.4)mm, the opening shape "↓" and the closing shape "↑" were normal. At 3 and 6 months after treatment, the oral opening was (38.98±1.08) mm and (39.73±1.76) mm, respectively. The opening degree of control group was (36.85±2.33) mm 2 weeks after treatment, and the characteristic abnormal opening and closing pattern still existed. The opening degree of control group was (37.82±1.85) mm and (37.40±1.75) mm 3 and 6 months after treatment, respectively. The characteristic abnormal opening and closing pattern (stuffy, awkward, deliberate, unnatural) did not improve significantly. The openness of the experimental group was significantly higher than that of the control group (F=25.20, P<0.001). In the experimental group, 82.4% (28/34) had benign remodeling of condylar bone 6 months after treatment, and 17.6% (6/34) had no change of condylar bone. There was no significant change in condylar bone in control group. CBCT scores of the experimental group were (2.43±1.74) and (1.70±1.26) at 3 and 6 months after treatment, respectively. CBCT scores of the control group at 3 and 6 months after treatment were (4.23±1.50) and (4.10±1.37), they were significantly lower in the experimental group than in the control group (F=27.20, P<0.001). Conclusions: Full dentition occlusal splint can alleviate the pain in the joint area of TMJOA patients, but can not improve the characteristic abnormal mandibular movement, and the condyle bone repair is not obvious. SSFE can effectively relieve the symptoms and signs of TMJOA patients, especially improve the abnormal characteristic mandibular movement, and promote the normal reconstruction and repair of condylar bone.

Effect of feeding fresh forage plantain (Plantago lanceolata) or ryegrass-based pasture on methane emissions, total-tract digestibility, and rumen fermentation of nonlactating dairy cows

Plantain (Plantago lanceolata) is an herb used to reduce the forage deficit of ryegrass-based pastures during the summer. This herb is being promoted for its reduced environmental impact in terms of nitrogen emissions, particularly reducing urinary nitrogen. However, the effect of plantain on emissions of enteric CH₄, the main greenhouse gas produced from ruminant-based production systems, is not known. The aim of the present trial was to determine CH₄ emissions and rumen fermentation characteristics of nonlactating dairy cows fed 100% plantain (PLT) or 100% perennial ryegrass (RG; Lolium perenne) in 2 experiments (E1 and E2). The forages were in a vegetative growth stage in E1 and were in a reproductive growth stage in E2. Methane emissions from 16 cows in each experiment were measured in respiration chambers for 2 d. Methane emissions per unit of dry matter intake (CH₄ yield) were 15 and 28% less for cows fed PLT than those fed RG in E1 and E2, respectively. Dry matter digestibility of PLT was 7 and 27% less than that of RG in E1 and E2, respectively, and CH₄ per unit of dry matter digested was similar for PLT and RG in both experiments. There were only minor (but some significant) differences in rumen fermentation characteristics between cows fed PLT and RG in both experiments. In conclusion, CH₄ yield was lower for cows fed PLT compared with those fed RG in both experiments and this reduction was largely explained by the lesser dry matter digestibility of PLT.

Diagnostic Value of Sylvian Fissure Hyperechogenicity in Fetal SAH

BACKGROUND AND PURPOSE

Fetal SAH is an intracranial malformation. The typical diagnostic features of fetal SAH in ultrasound have not been reported. This study aimed to evaluate the diagnostic value of Sylvian fissure hyperechogenicity by prenatal ultrasound in fetuses with SAH.

MATERIALS AND METHODS

The features on ultrasound and MR imaging of 10 fetuses with SAH were reviewed and summarized. The diagnostic value of the Sylvian fissure in fetal SAH by prenatal ultrasound was evaluated.

RESULTS

The typical and most obvious manifestations of SAH during the prenatal period were hyperechogenicity in the subarachnoid cavity, especially in the Sylvian fissure; all 10 cases (10/10) had such manifestations. Other manifestations included a hyperecho in other sulci (6/10), especially in the subfrontal sulcus, superior temporal sulcus, or parieto-occipital sulcus; a hyperecho in the cisterns (8/10), especially in the suprasellar cistern, posterior cranial fossa, cisterna ambiens, or quadrigeminal cistern; and a hyperecho around the anterior and posterior longitudinal fissures (2/10). Combined hemorrhage in the parenchymal layer or ventricles (9/10) was found. In addition, Doppler ultrasound showed that the peak flow velocity in the MCA increased in 6 cases (6/10).

CONCLUSIONS

The homogeneous hyperechogenicity of the Sylvian fissure is an important clue for detecting and diagnosing fetal SAH by prenatal ultrasound. A diagnostic approach has been proposed for fetal SAH, which has great significance in further prognosis.

Promoting effect of the recombinant resuscitation promoting factors-2 of Rhodococcus erythropolis on petroleum degradation and cultivable bacterial diversities of the oil-contaminated soils

Resuscitation-promoting factors (Rpfs) belong to peptidoglycan hydrolases, which participate in recovery of dormant cells and promoting bacteria growth. In this study, the resuscitation promoting factor rpf2 gene of Rhodococcus erythropolis KB1 was expressed in Escherichia coli and purified by Ni²⁺ affinity chromatography. The purified recombinant fusion protein Rpf2 showed a closely 50 kDa band on sodium dodecyl sulphate polyacrylamide gel electrophoresis. The protein showed muralytic activity, with a specific activity of 1503 ± 123 U mg^-1 when determined with 4-methylumbelliferyl-β-d-N, N',N″-triacetotri-ylchitoside as substrate. It also showed protease activity when measured with azocasein as substrate, with a specific activity of 1528 ± 411 U mg^-1 . The addition of the recombinant Rpf2 protein significantly increased petroleum degradation efficiency of the indigenous micro-organisms and the petroleum degradation rates increased from 30·86 to 43·45%, 45·20 and 49·23% in the treatment groups. The recombinant protein also increased the petroleum-degrading bacterial diversities enriched from the contaminated soils. The cultivable bacterial flora of the treatment groups supplemented with different concentrations of Rpf2 increased from 82 genera in 9 phyla to 116 genera in 16 phyla and 138 genera in 16 phyla respectively. Thirteen extra petroleum-degrading bacteria strains were isolated from the petroleum-contaminated soils in the groups containing the recombinant Rpf2.

Theoretically exploring selective-binding mechanisms of BRD4 through integrative computational approaches

The origin of cancer is related to the dysregulation of multiple signal pathways and of physiological processes. Bromodomain-containing protein 4 (BRD4) has become an attractive target for the development of anticancer and anti-inflammatory agents since it can epigenetically regulate the transcription of growth-promoting genes. The synthesized BRD4 inhibitors with new chemical structures can reduce the drug resistance, but their binding modes and the inhibitory mechanism remain unclear. Here, we initially constructed robust QSAR models based on 68 reported tetrahydropteridin analogues using topomer CoMFA and HQSAR. On the basis of QSAR results, we designed 16 novel tetrahydropteridin analogues with modified structures and carried out docking studies. Instead of significant hydrogen bondings with amino acid residue Asn140 as reported in previous research, the molecular docking modelling suggested a novel docking pose that involves the amino acid residues (Trp81, Pro82, Val87, Leu92, Leu94, Cys136, Asp144, and Ile146) at the active site of BRD4. The MD simulations, free energy calculations, and residual energy contributions all indicate that hydrophobic interactions are decisive factors affecting bindings between inhibitors and BRD4. The current study provides new insights that can aid the discovery of BRD4 inhibitors with enhanced anti-cancer ability.

Role of Equilibrium Fluctuations in Light-Induced Order

Engineering novel states of matter with light is at the forefront of materials research. An intensely studied direction is to realize broken-symmetry phases that are "hidden" under equilibrium conditions but can be unleashed by an ultrashort laser pulse. Despite a plethora of experimental discoveries, the nature of these orders and how they transiently appear remain unclear. To this end, we investigate a nonequilibrium charge density wave (CDW) in rare-earth tritellurides, which is suppressed in equilibrium but emerges after photoexcitation. Using a pump-pump-probe protocol implemented in ultrafast electron diffraction, we demonstrate that the light-induced CDW consists solely of order parameter fluctuations, which bear striking similarities to critical fluctuations in equilibrium despite differences in the length scale. By calculating the dynamics of CDW fluctuations in a nonperturbative model, we further show that the strength of the light-induced order is governed by the amplitude of equilibrium fluctuations. These findings highlight photoinduced fluctuations as an important ingredient for the emergence of transient orders out of equilibrium. Our results further suggest that materials with strong fluctuations in equilibrium are promising platforms to host hidden orders after laser excitation.

Twist-Angle-Dependent Ultrafast Charge Transfer in MoS2-Graphene van der Waals Heterostructures

Vertically stacked transition metal dichalcogenide-graphene heterostructures provide a platform for novel optoelectronic applications with high photoresponse speeds. Photoinduced nonequilibrium carrier and lattice dynamics in such heterostructures underlie these applications but have not been understood. In particular, the dependence of these photoresponses on the twist angle, a key tuning parameter, remains elusive. Here, using ultrafast electron diffraction, we report the simultaneous visualization of charge transfer and electron-phonon coupling in MoS₂-graphene heterostructures with different stacking configurations. We find that the charge transfer timescale from MoS₂ to graphene varies strongly with twist angle, becoming faster for smaller twist angles, and show that the relaxation timescale is significantly shorter in a heterostructure as compared to a monolayer. These findings illustrate that twist angle constitutes an additional tuning knob for interlayer charge transfer in heterobilayers and deepen our understanding of fundamental photophysical processes in heterostructures, of importance for future applications in optoelectronics and light harvesting.

Conformer-specific photochemistry imaged in real space and time

[Figure: see text].

Intracardiac versus transesophageal echocardiography for diagnosis of left atrial appendage thrombosis in atrial fibrillation: A meta-analysis

INTRODUCTION

Left atrial appendage (LAA) thrombus in patients with atrial fibrillation is usually detected by transesophageal echocardiography (TEE). Intracardiac echocardiography (ICE) can be a suitable alternative to detect thrombosis. However, the effectiveness of the two methods for detecting LAA thrombus is still unclear, we performed a meta-analysis that compared ICE versus TEE for LAA thrombosis.

METHODS

We searched PubMed, Cochrane Library, and Embase for published abstracts and manuscripts on June 1, 2020. The analysis was performed using RevMan 5.3, STATA 15, and Meta-Disc 1.4.

RESULTS

Eight studies consists of 1108 patients (TEE = 558 vs. ICE = 550) were included. The average sensitivity of ICE and TEE to diagnose LAA thrombus is 1.0 (95% CI: 0.91-1.00) versus 0.68 (95% CI: 0.49-0.83), and specificity of ICE and TEE to diagnosis of LAA thrombus is 1.0 (95% CI: 0.99-1.00) versus 0.98 (95% CI: 0.96-0.99). The AUC of ICE and TEE is 0.9846 (SEAUC = 0.0196) and 0.9655 (SEAUC = 0.0401), and the Q* statistics is 0.9462 (SEQ* = 0.0406) and 0.9127 (SEQ * = 0.0616), respectively. Z test was performed on Q* statistics (Z = 0.45, p > .05).

CONCLUSION

The ICE and TEE have similar diagnostic efficacy for LAA thrombosis, but the ICE has higher sensitivity. Compared with TEE, ICE may be more advantages and prospects for clinical application.

Highly Efficient Uniaxial In-Plane Stretching of a 2D Material via Ion Insertion

On-chip dynamic strain engineering requires efficient micro-actuators that can generate large in-plane strains. Inorganic electrochemical actuators are unique in that they are driven by low voltages (≈1 V) and produce considerable strains (≈1%). However, actuation speed and efficiency are limited by mass transport of ions. Minimizing the number of ions required to actuate is thus key to enabling useful "straintronic" devices. Here, it is shown that the electrochemical intercalation of exceptionally few lithium ions into WTe₂ causes large anisotropic in-plane strain: 5% in one in-plane direction and 0.1% in the other. This efficient stretching of the 2D WTe₂ layers contrasts to intercalation-induced strains in related materials which are predominantly in the out-of-plane direction. The unusual actuation of Li_x WTe₂ is linked to the formation of a newly discovered crystallographic phase, referred to as Td', with an exotic atomic arrangement. On-chip low-voltage (<0.2 V) control is demonstrated over the transition to the novel phase and its composition. Within the Td'-Li_{0.5- δ} WTe₂ phase, a uniaxial in-plane strain of 1.4% is achieved with a change of δ of only 0.075. This makes the in-plane chemical expansion coefficient of Td'-Li_0.5-δ WTe₂ far greater than of any other single-phase material, enabling fast and efficient planar electrochemical actuation.

A magnetic resonance imaging study on the temporomandibular joint disc-condyle relationship in young asymptomatic adults

The aim of this study was to assess the temporomandibular joint (TMJ) disc-condyle relationship in asymptomatic young adults. Ninety-three volunteers aged 19-23 years without temporomandibular disorder (TMD) symptoms underwent TMJ magnetic resonance imaging (MRI). The condylar centre and apex methods were used to measure and analyse the position of the disc in the oblique sagittal plane, and the reliability of the two methods was compared by calculating the intra-class correlation coefficient (ICC). Furthermore, 18 of the volunteers were randomly selected for three-dimensional (3D) reconstruction of the TMJ structure and the disc-condyle relationship. The 3D TMJ structure was established by semi-automatic segmentation of the condyle and articular disc in ITK-SNAP software; the condylar apex method was then performed. It was found that only 33.3% of the posterior edge of the articular discs were located in the normal 12 o'clock position with respect to the condyle. Moreover, this study suggests that the condylar centre method lacks accuracy when compared to the condylar apex method in regard to the measurement of the TMJ disc-condyle relationship (0 < ICC_cen < ICC_apex < 1). The position of the articular disc (left and right) was more forward in young women when compared to young men. However, there was no significant difference in the TMJ disc-condyle position between the left and right sides in the same individual, although the two joint discs in the same individual were not completely symmetrical.

A multiperiod grey prediction model and its application

The purpose of this paper is to solve the prediction problem of nonlinear sequences with multiperiodic features, and a multiperiod grey prediction model based on grey theory and Fourier series is established. For nonlinear sequences with both trend and periodic features, the empirical mode decomposition method is used to decompose the sequences into several periodic terms and a trend term; then, a grey model is used to fit the trend term, and the Fourier series method is used to fit the periodic terms. Finally, the optimization parameters of the model are solved with the objective of obtaining a minimum mean square error. The novel model is applied to research on the loss rate of agricultural droughts in Henan Province. The average absolute error and root mean square error of the empirical analysis are 0.3960 and 0.5086, respectively. The predicted results show that the novel model can effectively fit the loss rate sequence. Compared with other models, the novel model has higher prediction accuracy and is suitable for the prediction of multiperiod sequences.

Source identification of particulate organic carbon using stable isotopes and n-alkanes: modeling and application

Particulate organic carbon (POC) sources, which regulate dissolved organic carbon, sediment organic carbon, and inorganic carbon via deposition, degradation, and mineralization, play an important role in lake ecosystems. Linear or Bayesian algorithms on isotope and n-alkanes have been widely used to identify the source proportion of organic carbon. However, the applicability of these methods is ambiguous because of the unilateral advantages of each model and trace factors. To test the applicability of the various methods for identifying POC sources, we analyzed dual isotopes and n-alkanes in surface water samples of Lake Taihu, and Multi-source mixing model and Bayesian mixing model were used to distinguish between endogenous and exogenous contributions. Carbon isotope presented a clear advantage in West Taihu (-21.85 ± 0.78‰) and Southwest Taih (-22.61 ± 1.35‰); nitrogen isotope also showed high values in Meiliang Bay (9.76 ± 0.92‰). The majority of the lake was dominated by short-chain n-alkanes, except for East Taihu Lake (dominated by medium-chain n-alkanes) and areas with riverine input (dominated by long-chain n-alkanes). Different principles between the Bayesian mixing model (based on the Markov Chain Monte Carlo algorithm) and the Multi-source mixing model (based on linear estimation) caused discrepancies in the estimations of source contributions. But the fraction of chemical compounds during the migration process, and the overlap of potential sources play important role in the inconsistency of results. The estimations from the different models were consistent in indicating the dominance of endogenous organic carbon in Lake Taihu (mean of 60.18 ± 20.26%), particularly in the north and western regions (West Taihu, Meiliang Bay, and Southwest Taihu). This was likely due to algal aggregation influenced by human activities and climatic factors.

Effects of Superparamagnetic Iron Nanoparticles on Electrocatalysts for the Reduction of Oxygen

It is of great research interest to understand the nanostructures contributing to the activity observed in the reduction of oxygen by non-platinum group metal (PGM) electrocatalysts in acidic media. Iron- and nitrogen-containing carbon networks are often the most studied structures, among which single-atom iron-coordinated nitrogen (FeN_x) moieties have often been proposed to be the structures leading to the high activity in these non-PGM electrocatalysts. Iron nanoparticles embedded within a carbon support are also formed under certain conditions as a result of the synthetic processes in making non-PGM electrocatalysts. In this study, we present a study to understand the oxygen reduction reaction (ORR) activity of prepared iron- and nitrogen-containing non-PGM electrocatalysts obtained through the pyrolysis of metal-organic framework (MOF) precursors. We studied the structure-property relationship among nanostructures made from the MOF precursor ZIF-8 under different pyrolysis conditions. Density functional theory calculations were used to explain the effect of structural moieties on the ORR activity. Our results suggest that iron-coordinated C-N structures and iron nanoparticles act synergistically to catalyze the ORR.

Effects of astragalus polysaccharide on intestinal inflammatory damage in goslings infected with gosling plague

1. This study explored the effects of Astragalus membranaceus polysaccharide (APS) on intestinal inflammatory damage of goslings infected with parvovirus ('gosling plague').2. A total of 90 healthy goslings were randomly divided into three groups; control, infected or APS treated, respectively. Goslings in the infection and APS treatment groups were inoculated with 0.3 ml allantoic fluid containing goose parvovirus (ELD₅₀ = 1 × 10³/0.3 ml) by intramuscular injection and the control group were injected with saline (0.3 ml) twice a day for 15 days.3. Blood serum and the jejunum were collected at 5, 10 and 15 days after the start of the experiment to detect the activities of SOD and GSH-Px, levels of MDA, sIgA, IL-1β, IL-6 and TNF-α, the mRNA expression of IL-1β, IL-6, LITAF, NF-κB, COX-2 and PGE2, pathological damage in the jejunum and serum IgG, IgM, C3, C4, IFN-γ levels.4. After APS treatment, SOD and GSH-Px activities increased, MDA content decreased; sIgA, IL-1β, IL-6 and TNF-α protein content, and IL-1β, IL-6, LITAF, NF-κB, COX-2 and PGE2 mRNA expression decreased in the jejunal tissue, serum IgG, IgM, C3, C4, IFN-γ significantly increased and pathological damage of jejunum significantly improved.5. In conclusion, APS reduced intestinal inflammatory damage in goslings infected with parvovirus by improving the immune and antioxidant functions of goslings.

[Histopathological and molecular characteristics of metaplastic thymomas: report of five cases]

Objective: To investigate the clinicopathological characteristics, immunophenotype, molecular genetic characteristics and prognosis of the metaplastic thymoma (MT). Methods: The clinicopathological and follow-up data of five MT cases were collected at Fujian Provincial Hospital from 2008 to 2019. Immunohistochemical staining and MAML2 gene detection were performed, and the relevant literature was reviewed. Results: There were 2 males and 3 females, aged 36-64 years (mean age 52 years). The tumors ranged 3.2-7.3 cm in the greatest diameter (average 5.1 cm).Microscopically, the tumor showed a biphasic pattern with epithelial cells merging gradually with the spindle cell component. The two areas transited to each other or had obvious boundary. Both components showed mild atypia. No mitosis was observed in either area, and a small number of lymphocytes were observed in the stroma. Immunohistochemical staining showed that epithelioid cells were positive for CKpan, p63 and E-cadherin. Spindle cells were positive for vimentin and EMA, while the Ki-67 index was less than 5%, and lymphocytes were negative for TdT. MAML2 gene apart signal was detected in two of the cases (2/4) that were tested by FISH. Conclusions: MT is a low-grade malignant epithelioid thymic tumor. Its diagnosis and differential diagnosis are dependent on the morphological characteristics, immunohistochemical staining and MAML2 gene detection. The primary treatment option is surgical resection, with an overall good prognosis.

Creation and Characterization of Matter-Wave Breathers

We report the creation of quasi-1D excited matter-wave solitons, "breathers," by quenching the strength of the interactions in a Bose-Einstein condensate with attractive interactions. We characterize the resulting breathing dynamics and quantify the effects of the aspect ratio of the confining potential, the strength of the quench, and the proximity of the 1D-3D crossover for the two-soliton breather. Furthermore, we demonstrate the complex dynamics of a three-soliton breather created by a stronger interaction quench. Our experimental results, which compare well with numerical simulations, provide a pathway for utilizing matter-wave breathers to explore quantum effects in large many-body systems.

Coherent Lattice Wobbling and Out-of-Phase Intensity Oscillations of Friedel Pairs Observed by Ultrafast Electron Diffraction

The inspection of Friedel's law in ultrafast electron diffraction (UED) is important to gain a comprehensive understanding of material atomic structure and its dynamic response. Here, monoclinic gallium telluride (GaTe), as a low-symmetry, layered crystal in contrast to many other 2D materials, is investigated by mega-electronvolt UED. Strong out-of-phase oscillations of Bragg peak intensities are observed for Friedel pairs, which does not obey Friedel's law. As evidenced by the preserved mirror symmetry and supported by both kinematic and dynamic scattering simulations, the intensity oscillations are provoked by the lowest-order longitudinal acoustic breathing phonon. Our results provide a generalized understanding of Friedel's law in UED and demonstrate that by designed misalignment of surface normal and primitive lattice vectors, coherent lattice wobbling and effective shear strain can be generated in crystal films by laser pulse excitation, which is otherwise hard to achieve and can be further utilized to dynamically tune and switch material properties.

[Study on the matching feature of current parameters for inducing contraction of orbicularis oris muscle by artificial facial nerve in rabbit with peripheral facial paralysis]

Objective: To explore the optimal matching of the current parameters about artificial facial nerve (AFN) for inducing contraction of the orbicularis oris muscle (OOM) in rabbit with peripheral facial paralysis. Methods: According to the combinations of different stimulus parameters, at different time points, we used AFN to induce contraction of the affected side OOM of the paralyzed rabbit in waking state. We recorded the current amplitudes of the threshold stimulation and peak stimulation under each combination, then compared the total charge of the stimulus consumption under different combinations. Results: Compared the total stimulus charge consumption of the AFN threshold stimulation and that in the peak stimulation respectively under different stimulus frequency and pulse width matching combinations, we found that the frequency, the pulse width and the interaction of the frequency and pulse width among different groups could affect the total charge, the differences were statistically significant (P<0.05). Conclusions: When AFN stimulus frequency is 60 Hz and the stimulus pulse width is 100 μs, the output current intensity is relatively lowest and the total consumed charge is the lowest under the premise of effectively inducing the paralytic side OOM contraction. Thus we recommend this stimulus parametric combination as the optimal combination for meeting the low power consumption of AFN.

Sediment record of polycyclic aromatic hydrocarbons in Dianchi lake, southwest China: Influence of energy structure changes and economic development

Sixteen polycyclic aromatic hydrocarbons (PAHs) in a sediment core from Dianchi Lake, southwest China, were analysed. The influence of changes in China's energy structure for 2-6 ringed PAHs was investigated to assess sources and the impact of socioeconomic development on temporal changes in concentrations. The concentration of the ΣPAH₁₆ ranged from 746 to 2293 ng g^-1. Prior to the 1960s relatively low concentrations of the ΣPAH₁₆ and a larger proportion of 2-3-ring PAHs indicated that biomass combustion was the main source of PAHs. A rapid increase in the concentrations of 2-3 ring PAHs between 1975 and 2004 was attributed to population growth and coal consumption. A declining trend since 2004 was interpreted as being due to local changes in household energy usage. Increased concentrations of 4-ring PAH between 1975-2005 and 5-6-ring PAHs between the 1980s to 2004 showed correlations with increased coal consumption and the number of motor vehicles, respectively. These were caused by rapid urbanization and industrialization in the Dianchi watershed following the implementation of the Reform and Open Policy in 1978. A subsequent decline in the concentrations of 4-ring and 5-6-ring PAHs may have been due to decreased coal consumption and improvements in emission standards, respectively. Source apportionment by a PMF model revealed that coal combustion (29.2%), vehicle emissions (24.2%), petrogenic sources (21.8%), and biomass combustion (24.9%) were the sources of PAHs in the lake sediment core, and that coal combustion was the most important regional source of PAHs pollution.