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Rationale: The challenge of glycan identification due to their structural complexity and diversity has profited enormously from recent developments in mass spectrometry (MS)‐related methods. For photodissociation MS, infrared (IR) and ultraviolet (UV) lasers can generate complementary fragment ions, so an effective combination of the two methods may provide rich and valuable fragmentation patterns for glycan analysis. Methods: A 7.0 T Fourier transform ion cyclotron resonance (FTICR) mass spectrometer equipped with a double‐beam laser system was applied for the experiments. 3,5‐Diiodo‐L‐tyrosine was selected as the assistant molecule to form complex ions with ten isomeric disaccharides through electrospray ionization. The complex ions were further isolated and irradiated by IR and UV lasers separately or continuously in the FTICR cell. Results: By combining the two complementary fragment spectra generated from the IR and UV lasers, a clear identification of all the ten isomers was achieved using their binary codes based on their fragmentation patterns. The double‐beam method simplifies the experiment by introducing the two lasers sequentially in one experiment, providing richer fragmentation patterns and making the full discrimination easier. Conclusions: This study demonstrates the capabilities of the combination of IR and UV photodissociation MS in the identification of diverse glycan isomers. The double‐beam photodissociation method described here distinguished compositional, configurational and connectivity disaccharide isomers successfully. Compared with the data accumulation method based on separate IR and UV experiments, this method is simpler, faster, more flexible and also characterized by richer fragmentation patterns. [ABSTRACT FROM AUTHOR]

Film mulching rice cultivation pattern can effectively relieve seasonal drought and chilling damage during rice production. Film mulching cultivation pattern could reduce the consumption of irrigation water and improve grain yield on the basis of increasing soil temperature. However, the application of film mulching increased production cost and environmental pollution was occurred by non-degradable mulch. Therefore, the biodegradable film and matching mulch machines were applied and studied, the development of film mulching cultivation was promoted. It can effectively control weeds, reduce the loss of fertilizer, increase its use efficiency, reduce the application quantity of pesticides and chemical fertilizer, and provide a new idea for the green high-yield and high-efficiency cultivation of rice. This paper systematically expounded the advantages and disadvantages of the existing film-mulching rice cultivation in rice production, and prospects the future development of rice film mulching cultivation. [ABSTRACT FROM AUTHOR]

The kk-center clustering is one of the well-studied clustering problems in computer science. We are given a set of data points P⊆RdP⊆Rd, where RdRd is dd dimensional Euclidean space. We need to select k≤|P|k≤|P| points as centers and partition the set PP into kk clusters with each point connecting to its nearest center. The goal is to minimize the maximum radius. We consider the so-called online kk-center clustering model where the data points in RdRd arrive over time. We present the bi-criteria (nk,(logU∗L∗)2)(nk,(log⁡U∗L∗)2)-competitive algorithm and (nk,logγlognγk)(nk,log⁡γlog⁡nγk)-competitive algorithm for semi-online and fully-online kk-center clustering respectively, where U∗U∗ is the maximum cluster radius of optimal solution, L∗L∗ is the minimum distance of two distinct points of PP, γγ is the ratio of the maximum distance of two distinct points and the minimum distance of two distinct points of PP and nn is the number of points that will arrive in total. [ABSTRACT FROM AUTHOR]

With the growing maritime economy, ensuring the quality of communication for maritime users has become imperative. The maritime communication system based on nearshore base stations enhances the communication rate of maritime users through dynamic resource allocation. A virtual queue-based deep reinforcement learning beam allocation scheme is proposed in this paper, aiming to maximize the communication rate. More particularly, to reduce the complexity of resource management, we employ a grid-based method to discretize the maritime environment. For the combinatorial optimization problem of grid and beam allocation under unknown channel state information, we model it as a sequential decision process of resource allocation. The nearshore base station is modeled as a learning agent, continuously interacting with the environment to optimize beam allocation schemes using deep reinforcement learning techniques. Furthermore, we guarantee that grids with poor channel state information can be serviced through the virtual queue method. Finally, the simulation results provided show that our proposed beam allocation scheme is beneficial in terms of increasing the communication rate. [ABSTRACT FROM AUTHOR]

Objective: To present a meta-analysis of high-quality published reports comparing laparoscopic rectal resection (LRR) and open rectal resection (ORR) for rectal cancer.Methods: Studies that compared LRR and ORR and were published within the last 5 years were identified. All eligible randomized controlled trials (RCTs) and non-randomized comparative trials (NRCTs) were evaluated based on the Jadad score, the Cochrane risk of bias assessment tool and modified Methodological Indices for Nonrandomized Studies (MINORS). The mean differences (MD) and odds ratios (OR) were used to compare the operative time, blood loss, mortality, complications, harvested lymph nodes, hospital stay, distal resection margin, and circumferential resection margin. The risk ratio (RR) method was used to examine recurrence and survival.Results: Fourteen studies were identified and included 7 RCTs and 7 NRCTs and 4353 patients (2251 LRR, 2102 ORR). Although the operation time of the LRR group was obviously longer than that of the conventional surgery group (MD = 25.64, 95%CI = [5.17,46.10], P = 0.01), LRR was associated with fewer overall complications (OR = 0.67, 95%CI = [0.52,0.87], P = 0.002), less blood loss (MD = -66.49, 95%CI = [-88.31, -44.66], P < 0.00001), shorter postoperative hospital stays (OR = -1.26,95%CI = [-2.45, -0.07],P = 0.004) and shorter bowel function recovery times (MD = -0.93, 95%CI = [-1.27,-0.58], P < 0.00001). Moreover, the difference in the DRM was statistically clear (MD = 0.14, 95%CI = [0.02,0.27], P = 0.03). However, no significant differences between the LRR and ORR groups were observed in terms of the number of lymph nodes harvested, mortality, positive CRM, local and distal recurrence, or overall and disease-free survival.Conclusions: This study indicates that there are no significant differences between LRR and ORR in terms of survival and pathological outcomes with the exception of the DRM. Moreover, this study suggests that LRR can be performed safely and elicits faster recovery times compared with conventional surgery. [ABSTRACT FROM AUTHOR]

• A strict COVID-19 epidemic clearance policy might impact the outcomes of hospitalized patients. • During the COVID-19 pandemic lockdown, hospitalized patients with cerebrovascular disease fell by 12.6% • There were substantial increases in out-of-pocket rates and in-hospital case fatality rates. • Clinicians need to ensure stroke treatment and care in the upcoming challenging times. The aim of this nationwide study was to assess the impact of the COVID-19 pandemic on cerebrovascular disease hospitalization rates, out-of-pocket rates, and in-hospital case fatality rates. All hospitalizations for cerebrovascular disease from 1599 hospitals from 2019 to 2020 were selected using the International Classification of Diseases, 10th revision, in the Hospital Quality Monitoring System (HQMS). We defined 2019 as the pre-pandemic group and 2020 as the post-pandemic group. Multivariate analyses were done to assess the association between the pandemic and patient outcomes and out-of-pocket rate with odds ratios (OR) and 95% CIs presented. In total, 9 640 788 patients with the cerebrovascular disease were recruited (mean age was 65.7[SE.0.004] years, and 55.7% were male), and data is available for 5145358 patients in 2019 (pre-epidemic) and 4495430 patients in 2020(post-pandemic), indicating a 12.6% decrease. Out-of-pocket rate increase of 9.3% (2020 vs 2019: 34.1%% vs 31.2% [absolute difference, 2.9% {95% CI, 1.3% to 4.5%}, odd ratio {OR}, 1.1{95% CI, 1.0 to 1.1}]. The epidemic has led to an 18.0% increase in in-hospital mortality (2020 vs 2019: 1.1%% vs 0.9% [absolute difference, 0.2% {95% CI, 0.1% to 0.2%}, odd ratio {OR}, 1.1{95% CI, 1.1 to 1.2}]. The epidemic has led to significantly increased in-hospital mortality for patients with stroke but had no significant impact on other cerebrovascular diseases. During the COVID-19 pandemic lockdown, patients hospitalized for stroke fell by 12.6%, and there were substantial increases in out-of-pocket rates (9.3%) and in-hospital case fatality rates (18.0%). [ABSTRACT FROM AUTHOR]

Near-infrared (NIR) persistent luminescence (PersL) materials have interesting invisible self-luminescent properties, but most of them can only be effectively activated by UV light. In the present study, Ca 0.97 TiO 3 :Y 0.02 (CaTiO 3 :Y) is found with visible-light-excited PersL at ∼770 nm lasting at least for 5 h. The PersL is derived from the broad absorption of Ti3+, which is stabilized by Y3+-doping via a charge compensation strategy. The PersL excitation spectrum has a peak at ∼ 400 nm, extending to 720 nm. Y3+-doping at Ca2+ site stimulates the generation of more oxygen vacancies and the stabilization of luminescent Ti3+. The Cr-free property makes CaTiO 3 :Y an environmentally friendly anti-counterfeiting luminescent material. The interaction between narrow band gap CaTiO 3 and proper energy levels of Ti3+ is of vital importance in the successful development of visible-light-excited PersL materials. This study provides a new member of Cr-free NIR PersL material with intense visible-light-excited luminescent property and has certain guidance on developing other visible-light-excited PersL materials. • CaTiO 3 :Y 0.02 was synthesized with visible-light-excited persistent luminescence at ∼770 nm. • The room-light-activated persistent luminescence lasted for more than 5 h. • The persistent luminescence was derived from Ti3+ emission. • Y3+ stabilized Ti3+ via charge compensation during the annealing synthesis process in air. • CaTiO 3 :Y 0.02 has potential application as an environment-friendly anti-counterfeiting material. [ABSTRACT FROM AUTHOR]

As an exquisite asset of Chinese traditional culture, traditional opera occupies a place of high esteem within the world's cultural and artistic treasury. The impact of emerging cultures has threatened the future of traditional opera culture, necessitating a thorough examination of the historical context of the Grand Canal and traditional opera. There is insufficient research on the spatial evolution of the traditional opera culture along the Grand Canal; thus, this study takes ancient opera stages, a representative cultural relic of traditional opera, as an entry point and employs methods such as kernel density analysis and standard deviation ellipse analysis to analyze the spatial and temporal distribution patterns of the traditional opera culture along the Grand Canal. The results showed that: (i) Nationwide, opera stages in the areas along the Grand Canal exhibit a significant clustering characteristic. (ii) The changes in the number and locations of opera stages in the areas along the Grand Canal are closely related to the rise and fall of the Canal. The opera stages emerged along the Canal, gradually prospered with the development of the Canal, and finally clustered in a band-like cluster along the Grand Canal. (iii) From the Ming Dynasty to the founding of the People's Republic of China, the opera stages in the areas along the Grand Canal spread in the "southeast–northwest" direction, which was consistent with the main direction of the Grand Canal, indicating its driving influence. (iv) On the centennial scale, from the 14th century to the 20th century, the evolution characteristics of the distribution centroid of opera stages in the areas along the Grand Canal were closely related to the key time nodes of Grand Canal construction and basin expansion. This study reveals the relationship between the Grand Canal and the spatial pattern evolution of traditional opera culture, aiming to promote the construction of the Grand Canal cultural belt. [ABSTRACT FROM AUTHOR]

Nowadays, focus is on encapsulating a greater variety and amount of metal species into fullerene cages due to their diverse structures and fascinating properties. Nevertheless, the encapsulation of more positively charged metal atoms inside one cage means more Coulomb repulsion, which makes the formation of such endohedral metallofullerenes (EMFs) difficult. In general, non-metallic atoms such as N and O should be introduced as mediators for the formation of trimetallic or tetrametallic endohedral fullerenes. However, it is still unknown whether metal atoms can serve as mediators themselves to form such EMFs. In this paper, the endohedral tetrametallic fullerene La3Pt@C98 with the platinum atom as a metallic mediator is reported. The EMFs of La3Pt@C2n (2n = 98–300) were generated by the method of laser ablation in the gas phase and verified by mass spectrometry. Among them, the EMF of La3Pt@C98 was selected and studied by theoretical calculations. Results show that the two most stable isomers are La3Pt@C2(231010)-C98 and La3Pt@C1(231005)-C98. For both of them, the inner La3Pt metallic cluster appears in a pyramidal shape, different from the planar triangular pattern of La3N clusters previously reported. Further calculations prove the existence of encaged La–Pt bonds in the La3Pt cluster. It was also revealed that the negatively charged Pt atom is situated near the center of the four-center two-electron (4c–2e) metal bond with the highest occupancy number. The platinum-mediated cluster stabilizes the EMFs greatly, promising the possibility of synthesizing new species of Pt-containing EMFs. [ABSTRACT FROM AUTHOR]