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Coastal marshes are transitional areas between terrestrial and aquatic ecosystems. They are sensitive to climate change and anthropogenic activities. In recent decades, the reclamation of coastal marshes has greatly increased, and its effects on microbial communities in coastal marshes have been studied with great interest. Most of these studies have explained the short-term spatiotemporal variation in soil microbial community dynamics. However, the impact of reclamation on the community composition and assembly processes of functional microbes (e.g., ammonia-oxidizing prokaryotes) is often ignored. In this study, using quantitative polymerase chain reaction and the Ion S5™ XL sequencing platform, we investigated the spatiotemporal dynamics, assembly processes, and diversity patterns of ammonia-oxidizing prokaryotes in 1 000-year-old reclaimed coastal salt marshes. The taxonomic and phylogenetic diversity and composition of ammonia oxidizers showed apparent spatiotemporal variations with soil reclamation. Phylogenetic null modelling-based analysis showed that across all sites, the archaeal ammonia-oxidizing community was assembled by a deterministic process (84.71%), and deterministic processes were also dominant (55.2%) for ammonia-oxidizing bacterial communities except for communities at 60 years of reclamation. The assembly process and nitrification activity in reclaimed soils were positively correlated. The abundance of the amoAgene and changes in ammonia-oxidizing archaeal and bacterial diversities significantly affected the nitrification activity in reclaimed soils. These findings suggest that long-term coastal salt marsh reclamation affects nitrification by modulating the activities of ammonia-oxidizing microorganisms and regulating their community structures and assembly processes. These results provide a better understanding of the effects of long-term land reclamation on soil nitrogen-cycling microbial communities.

Revealing the origins of kinetic selectivity is one of the premier tasks of applied theoretical organic chemistry, and for many reactions, doing so involves comparing competing transition states. For some reactions, however, a single transition state leads directly to multiple products, in which case non-statistical dynamic effects influence selectivity control. The selectivity of photochemical reactions—where crossing between excited-state and ground-state surfaces occurs near ground-state transition structures that interconvert competing products—also should be controlled by the momentum of the reacting molecules as they return to the ground state in addition to the shape of the potential energy surfaces involved. Now, using machine-learning-assisted non-adiabatic molecular dynamics and multiconfiguration pair-density functional theory, these factors are examined for a classic photochemical reaction—the deazetization of 2,3-diazabicyclo[2.2.2]oct-2-ene—for which we demonstrate that momentum dominates the selectivity for hexadiene versus [2.2.2] bicyclohexane products.

Linear viscoelastic properties in both melt and solution states are reported for a series of poly(3,6-dioxa-1,8-octanedithiol) (polyDODT) made by reversible radical recombination polymerization (R3P) under conditions designed to produce linear (LDODT), cyclic (RDODT), and linear–cyclic mixtures (LRDODT). PolyDODT is amorphous (Tg< −50 °C) and highly flexible (entanglement molecular weight Me,lin≈ 1850 g/mol for LDODT). PolyDODT’s low Tgand low Me,linenable characterization over a wide dynamic range and a wide range of dimensionless weight-average molecular weight Zw= Mw/Me,lin. Measurements at temperatures from −57 to 100 °C provide up to 18 decades of reduced frequency, which is necessary to characterize RDODT melts with Zwfrom 23 to 300. The two highest-molecular-weight polymers in the present RDODT series have such high Mw(406k and 556k g/mol) that mass spectrometry, NMR spectroscopy, and even chemical assays for chain ends are unable to rule out up to 2 mol % of linear contaminant. By studying the samples in solution (using dilution to reduce Zw), we could compare their dynamics with those of previously established high-purity polystyrene (PS) rings (limited to Zw≤ 13.6). RDODT solutions with Zw< 15 (concentrations <5 wt % for RDODT-406k and 556k) have dynamic moduli G* that accord with LCCC-purified PS rings in terms of the frequency dependence (including the absence of a plateau), the progression of shapes of G* as a function of Zw, and the linear scaling of their zero-shear viscosity η0with Mw. The shape of G* as a function of Zwfor solutions of RDODT-406k and -556k also accords with lower MwRDODT melts (which have ≤1.3 mol % of linear contaminant). Thus, the measurement of the linear viscoelastic properties of appropriate concentrations of high Mw(>200k g/mol) putative cyclic polymers, in which linear chains evade spectroscopic detection, may provide an alternative means (though not fully proven) of validation of sample purity. When Zw> 15 (including all seven RDODT melts and eight of their solutions), G* has a rubbery plateau. This suggests that the onset of entanglement-like behavior in rings requires 4–5-fold greater Zwthan is required for linear chains. Further, the plateau moduli of RDODT samples are indistinguishable from GNoof the corresponding LDODT (melt or matched-concentration solutions). In entangled linear polymers, the observation that GNois independent of Zwfollows from limitations on lateral fluctuations due to neighboring chains becoming independent of position along a given chain. The present results for RDODT suggest that this holds for sufficiently long endless chains, too. While the RDODTs have the same GNoas entangled LDODTs, when Zw> 60, the terminal relaxation, if reached at all, of RDODT extends to orders of magnitude lower frequency than an entangled linear polymer of the same Zw. Consequently, the viscosity of RDODT with Zw> 60 increases with Zwmuch more strongly than the 3.4 power observed for entangled linear polymers. Finally, these novel polymers, with a disulfide-linked backbone and broad relaxation time distribution, may prove important in relation to biodegradable elastomers and materials with exceptional low-frequency dissipation, extending at least 12 decades below the onset of the rubbery plateau.

Purpose: To assess the effect of capsular bend and axial length on the rotational stability of toric IOL. Methods: The prospective study included patients with preexisting astigmatism that were implanted with Acrysof IQ Toric IOL. According to the pre‑operative axial length, all patients were divided into 2 groups: high myopia (AL ≥ 26 mm) group, and emmetropia or low to moderate myopia group (AL &lt;26 mm). High-speed Swept-source Optical Coherence Tomography (SS-OCT) radial scanning was performed after pupil dilation to obtain the toric IOL axial orientation and capsular bending index (CBI) at 1-day, 1-week, 1-month and 3-month intervals postoperatively. The correlation between the rotation of toric intraocular lens and the axial length or CBI was subsequently analyzed. Results: 68 eyes of 57 patients were included in the research. The rotation of toric IOL within the high myopia group was greater than the control group (P= 0.001, 1month postoperative). Capsular contact with the IOL was delayed in highly myopic eyes, although the results were not statistically significant (P= 0.094, 1-month postoperatively). There was a positive correlation between the degree of rotation and axial length at the interval found between 1-week and 1-month after the operation (r= 0.333, P= 0.005). There was a significant negative correlation between the IOL rotational speed and CBI (P&lt; 0.001). The regression equation was Y= −0.441*X + 1.712 (R2= 0.323, P&lt; 0.001). Conclusion: There was a significant negative correlation between the IOL rotation speed and the CBI, while the influence of the axial length and capsular bending mainly occurred between one week and one month after the operation.

This study focuses on the possible ionospheric anomalies before the Mw7.2 earthquake in Haiti on August 14, 2021. Based on the dual-frequency observation data of Global Navigation Satellite System (GNSS) stations and Global Ionosphere Maps (GIM) data products, the sliding interquartile range method was applied to detect and analyze the changes of ionospheric Total Electron Content (TEC) anomalies before the earthquake. The results show that the TEC anomalies over five GNSS stations show the common existence of anomalous times, which are July 28, August 1, August 2, August 7, and August 13, 2021, respectively. Combining space weather parameters and GIM, it is tentatively concluded that the TEC anomaly that appeared on August 1 (i.e., the 13th day before the earthquake) was not disturbed by geomagnetic storms and solar activity, and may be related to the breeding earthquake. An ionospheric anomaly close to 6 TECU was present near the epicenter 13 days before the earthquake, which is strongly associated with the peak variation of the equatorial anomaly. This suggests that an anomalously increased vertical electric field may have been generated before the earthquake, which in turn enhanced the “fountain effect” and created a strong northern hump.

Purpose Hippocampal-avoidance whole-brain radiotherapy (HA-WBRT) planning can present challenges. This study examines the influence of head tilt angles on the dosimetric characteristics of target and organs at risk (OARs), aiming to identify the optimal tilt angle that yields optimal dosimetric outcomes using tomotherapy (TOMO).Methods Eight patients diagnosed with brain metastases underwent CT scans at five tilt angles: [0°, 10°), [10°, 20°), [20°, 30°), [30°, 40°), and [40°, 45°]. Treatment plans were generated using TOMO and volumetric modulated arc therapy (VMAT). Dosimetric parameters including conformity index (CI), homogeneity index (HI), D2cc, D98%, and Dmeanof PTV, as well as Dmax, and Dmeanof OARs were analyzed. Furthermore, a comparison was made between the dosimetric parameters of TOMO and VMAT plans. Finally, delivery efficiency of TOMO plans were assessed.Results For the PTV, [40°, 45°] tilt angle demonstrated significantly better conformity, homogeneity, lower D2cc, and lower Dmeanfor the PTV. Regarding the OARs, the [40°, 45°] head tilt angle demonstrated significantly lower Dmaxand Dmeanin hippocampus, eyes, optic chiasm, and optic nerves. The [40°, 45°] tilt angle also showed significantly lower Dmaxfor brainstem and cochleas, as well as a lower Dmeanfor lens. In the [40°,45°] tilt angle for HA-WBRT, TOMO showed superior performance over VMAT for the PTV. TOMO achieved lower Dmaxfor brainstem, cochleas, optic nerves, and optic chiasm, as well as a lower Dmeanfor hippocampus. Furthermore, a significant correlation was found between delivery time and the PTV projection length in the sagittal plane.Conclusion The TOMO plan utilizing a tilt angle range of [40°, 45°] demonstrated superior PTV conformity and uniformity, along with enhanced OARs sparing. Furthermore, it exhibited a dosimetric advantage over VMAT for PTV and most OARs at the same angle range.

The efficacy of supervised deep learning in medical image analyses, particularly in pathology, is hindered by the necessity for extensive manual annotations. Annotating images at the gigapixel level manually proves to be a highly labor-intensive and time-consuming task. Semi-supervised learning (SSL) has emerged as a promising approach that leverages unlabeled data to reduce labeling efforts. In this work, we introduce Semi-Path, a practical SSL framework enhanced with active learning (AL) for gigapixel pathology tasks. Unlike existing methods that treat SSL and AL as independent components where AL incurs significant computational complexity to SSL, we propose a deep fusion of SSL and AL into a unified framework. Our framework introduces Informative Active Annotation (IAA) that employs a SSL-AL iterative structure to effectively extract knowledge from unlabeled pathology data. This structure significantly minimizes labeling efforts and computational complexity. Then, we propose Adaptive Pseudo-Labeling (APL) to address heterogeneity in class distribution, and prediction difficulty that are often observed in real-world pathology tasks. We evaluate Semi-Path on pathology image classification and segmentation tasks over three datasets that include WSIs from breast, colorectal, and brain tissues. The experimental results demonstrate the consistent superiority of Semi-Path over state-of-the-art methods.

The effects of minor Zn (0.2 at%, 0.4 at%, 0.6 at%) on the microstructures and mechanical properties of Mg-1.4Gd-1.2Y-0.15Zr (at%) alloys were systematically explored. Results reveal that increasing Zn content leads to the increase of the intergranular phases and the change of their composition from Mg24(Gd,Y)5phase and (Mg,Zn)3(Gd,Y) phase to 18R-LPSO phase and (Mg,Zn)3(Gd,Y) phase. Mg24(Gd,Y)5phase is body-centered cubic structure and shares the same lattice constant with Mg24Y5while (Mg,Zn)3(Gd,Y) phase is face-centered cubic structure with lattice constant of 0.72 nm, slightly lower than Mg3Gd. 18R-LPSO structure is identified to be monoclinic with c-axis not strictly vertical to the bottom surface but 93.5°. The growth patterns of intergranular phases change from the divorced growth to coupled growth as compositions change. Moreover, the mechanical performance improves with Zn rising, ascribed to the decrease of brittle phases at grain boundaries and the increase of LPSO structure phases.

Sour bamboo shoot is a popular traditional fermented vegetable in southern China. The current study aims to clarify the relationship among physicochemical properties, flavor, and microbial compositions of sour bamboo shoots during fermentation. Four organic acids (OAs) were considered to be the main acids in sour bamboo shoots. At least 7 volatile compounds (OAV >1) were identified as the characteristic aroma substances, especially p-cresol, which accounted for the sour odor of sour bamboo shoots. The microbial community showed that Firmicutes and Proteobacteria were the dominant phyla, while Lactococcusand Lactobacilluswere the dominant genera in sour bamboo shoots. Correlation analysis indicated that Firmicutes positively correlated with p-cresol, phenol, 2-methoxy-phenol, malic acid, total titratable acidity (TTA), and some OAs. Lactococcuswas positively correlated with phenol, 2-methoxy-phenol, benzyl alcohol, TTA, some OAs, and amino acids (AAs). This study provided a theoretical basis for screening indigenous aroma-producing microorganisms as the starter of sour bamboo shoots.

Exploring the interleaving space of a multithreaded program to efficiently detect concurrency bugs is important but also difficult because of the astronomically many thread schedules. This paper presents a novel framework to decompose a thread schedule generator that explores the interleaving space into the composition of a basic generator and its extension under the “small interleaving hypothesis”. Under this framework, we in-depth analyzed research work on interleaving space exploration, illustrated how to design an effective schedule generator, and shed light on future research opportunities.

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