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Reducing cadmium (Cd) concentrations in rice grains is important for food safety, particularly in acid paddy fields in South China where the soils have been previously contaminated with Cd. A field experiment was conducted to evaluate the effects of four alkaline amendments, i.e., lime, compost, biochar, and carbide slag on soil bioavailability and uptake of Cd in plants of two rice cultivars ( Oryza sativa L.) in a Cd-contaminated acid paddy soil. The addition of these amendments significantly decreased the concentrations of CaCl 2 -extractable Cd by 13–41%. Cd in the acid-soluble fraction was decreased in these amended soils while it increased in the residual fraction. The amendments also decreased the uptake of Cd in the plants at the tillering and mature growth stages. The concentrations of Cd in plant tissues at maturity were in the order: root > shoot > bran > polished rice > husk. The amendment of carbide slag decreased Cd concentration in rice grains the most, followed by lime, biochar, and compost. The increases in soil pH and the decreases in the acid-soluble fraction of Cd (F1-Cd) indicated that these amendments can directly transform the highly availability fraction of Cd to a more stable fraction (residual Cd fraction) in soils. Furthermore, the Cd concentrations in polished rice grains of the two rice cultivars used were reduced by 66–67% by treatment with carbide slag. Our study suggests that carbide slag has a great potential to reduce the bioavailability and uptake of Cd in rice plants in Cd-contaminated acid paddy field soils.

Dear Editor, Parkinson＇s disease （PD） is a neurodegenerative disease that afflicts around 1% of the population over age 65 [1]. One of the pathological hallmarks of PD is the degeneration of dopaminergic （DA） neurons at midbrain and the relatively focal lesion feature of PD makes cell replacement a promising approach for treating the dis- ease [2].

According to the characteristics of longan cultivated in the hill and mountain regions of Maoming City,this paper analyzed the economic benefit of the simplified cultivation techniques. With 15-year-old Chuliang longan trees as materials,the economic benefit of four kinds of simplified cultivation technologies was compared and analyzed. After nine years of continuous technological application,it was found that the input costs increased by 1. 62%,and the output profits increased by 56. 10%; in input costs,labor cost decreased by 41. 33%,pesticide cost decreased by 24. 19%,and fertilizer cost increased by 33. 57%.

Enzymes provide scaffolds that facilitate chemical reactions. Enzyme dynamics often enhance reactivity by allowing the enzyme to sample the transition state between reactants and products. Kim et al. explored the role of dynamics in the dimeric enzyme fluoroacetate dehalogenase (see the Perspective by Saleh and Kalodimos). They found that the two protomers are asymmetric, with only one being able to bind substrate at a time. The nonbinding protomer contributed to catalysis by becoming more dynamic to compensate for the entropy loss of its partner. Science , this issue p. 10.1126/science.aag2355 ; see also p. 247 An enzyme homodimer engages both subunits—one binds substrate in its active site; the other allosterically enhances catalysis. Freeze-trapping x-ray crystallography, nuclear magnetic resonance, and computational techniques reveal the distribution of states and their interconversion rates along the reaction pathway of a bacterial homodimeric enzyme, fluoroacetate dehalogenase (FAcD). The crystal structure of apo-FAcD exhibits asymmetry around the dimer interface and cap domain, priming one protomer for substrate binding. This asymmetry is dynamically averaged through conformational exchange on a millisecond time scale. During catalysis, the protomer conformational exchange rate becomes enhanced, the empty protomer exhibits increased local disorder, and water egresses. Computational studies identify allosteric pathways between protomers. Water release and enhanced dynamics associated with catalysis compensate for entropic losses from substrate binding while facilitating sampling of the transition state. The studies provide insights into how substrate-coupled allosteric modulation of structure and dynamics facilitates catalysis in a homodimeric enzyme.

Quantum dots have found significant applications in photoelectric detectors due to their unique electronic and optical properties, such as tunable bandgap. Recently, colloidal quantum dots (CQDs) have attracted much interest because of the ease of controlling the dot size and low production cost. In this paper, a high-performance ZnO/PbS heterojunction photodetector was fabricated by spin-coating PbS CQDs onto the surface of a hydrothermally grown vertical array of ZnO nanowires (NWs) on an indium tin oxide (ITO) substrate. Under 940 nm near-infrared light illumination, the device demonstrated a responsivity and detectivity of ~3.9 × 104 A/W and ~9.4 × 1013 Jones, respectively. The excellent performances and low cost of this nanocomposite-based photodetector show that it has the potential for widespread applications ranging from medical diagnosis to environmental monitoring.

This paper presents a 14-bit hybrid column-parallel compact analog-to-digital converter (ADC) for the application of digital infrared focal plane arrays (IRFPAs) with compromised power and speed performance. The proposed hybrid ADC works in two phases: in the first phase, a 7-bit successive approximation register (SAR) ADC performs coarse quantization; in the second phase, a 7-bit single-slope (SS) ADC performs fine quantization to complete the residue voltage conversion. In this work, the number of unit capacitors is reduced to 1/128th of that of a conventional 14-bit SAR ADC, which is beneficial for the application of small pixel-pitch IRFPAs. In this work, a tradeoff segmented thermometer-coded digital-to-analog converter (DAC) is adopted in the first 7-bit coarse quantization process: the lower 3-bit is binary coded, and the upper 4-bit is thermometer coded. A thermometer-coded DAC can improve the linearity of ADC. Capacitor array matching can be incredibly relaxed compared with a binary-weight 14-bit SAR ADC, resulting in a noncalibration feature. Moreover, by sharing DAC and comparator analog circuits between the SAR ADC and the SS ADC, the power consumption and layout area are consequently reduced. The proposed hybrid ADC was fabricated using a 180 nm CMOS process. The measurement results show that the proposed ADC has a differential nonlinearity of −0.61/+0.84 LSB and a sampling rate of 120 kS/s. The developed ADC achieves a temporal noise of 1.7 LSBrms at a temperature of 77 K. In addition, the SNDR is 72.9 dB, and the ENOB is 11.82 bit, respectively. Total power consumption is 71 μW from supply voltages of 3.3 V (analog) and 1.8 V (digital).

Biomass burning is one of the key sources of urban aerosols in the North China Plain, especially during winter, when the impact of secondary organic aerosols (SOAs) formed from biogenic volatile organic compounds (BVOCs) is generally considered to be minor. However, little is known about the influence of biogenic SOA loading on the molecular composition of wintertime organic aerosols. Here, we investigated the water-soluble organic compounds in fine particulate matter (PM2.5) from urban Tianjin by ultrahigh-resolution Fourier transform ion cyclotron resonanc mass spectrometry (FT-ICR MS). Our results show that most of the CHO and CHON compounds are derived from biomass burning which are poor in oxygen and contain aromatic rings that probably contribute to light-absorbing brown carbon (BrC) chromophores. Under moderate to high SOA-loading conditions, the nocturnal chemistry is more efficient than photooxidation to generate secondary CHO and CHON compounds with high oxygen content. Under low SOA loading, secondary CHO and CHON compounds with low oxygen content are mainly formed by photochemistry. Secondary CHO compounds are mainly derived from oxidation of monoterpenes. However, nocturnal chemistry may be more productive to sesquiterpene-derived CHON compounds. In contrast, the number- and intensity-weight of S-containing groups (CHOS and CHONS) increased significantly with the increase of biogenic SOA loading, which agrees with the fact that a majority of the S-containing groups are identified as organosulfates (OSs) and nitrooxy–organosulfates (nitrooxy–OSs) that are derived from the oxidation of BVOCs. Terpenes may be potential major contributors to organosulfates and nitrooxy–organosulfates. While the nocturnal chemistry is more beneficial to the formation of organosulfates and nitrooxy–organosulfates under low SOA loading. The SOA loading is an important factor that is associated with the oxidation degree, nitrate group content and chemodiversity of nitrooxy-organosulfates. Furthermore, our study suggests that the hydrolysis of nitrooxy-organosulfates is a possible pathway for the formation of organosulfates.

Mollisols represent foundational agricultural soils in which high organic carbon (C) and active microbiomes sustain fertility and mediate global C cycling. However, decades of intensive cultivation have depleted soil organic C (SOC) and degraded soil structure and function. Enhancing C sequestration in agricultural Mollisols through the incorporation of organic residue, such as crop residues, organic waste, and spent mushroom substrates has become an urgent scientific and management priority. This review integrates advances from the past decade, combining stable isotope probing, multi-omics analyses, and ultrahigh-resolution molecular characterization to elucidate how microorganisms mediate C sequestration during organic residue return and decomposition. We propose a four-dimensional conceptual framework, “substrate–microenvironment–metabolic pathway–residue stabilization,” that links microbial metabolism with long-term C persistence in Mollisols. We further highlight that organic residue inputs promote CO2 sequestration via fermentation–autotrophy coupling, nitrifying autotrophy, and microbial mixotrophy. Major C sequestration pathways operate synergistically across redox microenvironments, forming stratified metabolic networks that sustain continuous C cycling. The chemical composition and decomposition kinetics of organic residue governs substrate and energy fluxes for microbial C sequestration, while soil redox status, and nutrient coupling (Carbon–Nitrogen–Phosphorus–Sulfur) collectively direct C flow toward stabilization. Microbial necromass and extracellular polymers achieve long-term C storage through mineral adsorption and microaggregate formation. Finally, we summarize recent methodological advances for tracing microbial CO2 sequestration in agricultural Mollisols and identify key research needs on residue formation, C use efficiency, and aggregate-mineral protection mechanisms. This synthesis establishes a mechanistic foundation for biologically regulated C management and offers guidance for sustainable cropland restoration.

Laser shock bulging process is a promising flexible microforming method in which the laser shock wave pressure is employed to cause plastic deformation and fabricate microfeatures on thin sheet metals. However, the influence of initial grain size and laser power density on the forming quality of bulged parts has not been well understood. In this paper, three various initial grain sizes as well as three levels of laser power densities were provided, and then, laser shock bulging experiments of T2 copper foil were conducted. The characteristics of bulging height, thickness distribution, microhardness, surface morphology, and microstructure were examined. It is revealed that the bulging height increases with the increase of grain size and the enhancement of laser power density. The exhibiting good formability of pure copper foil in laser shock bulging process is attributed to the inertial effect on necking stabilization and strain-rate effect on material constitutive behavior. The overall thickness of bulged parts decreases compared with its original thickness. Moreover, the microhardness in the laser-shocked region increases due to the strain hardening effect, but the microhardness distribution is nonuniform because of the inhomogeneous plastic deformation. The grain sizes of bulged parts are slightly refined with the increase of laser power density, especially for the coarse-grained part. The grain refinement in laser shock bulging forming process is attributed to the large plastic deformation at high strain rates under laser shock.

Lead sulfide colloidal quantum dots (PbS CQDs) are promising optoelectronic materials due to their unique properties, such as tunable band gap and strong absorption, which are of immense interest for application in photodetectors and solar cells. However, the tunable band gap of PbS CQDs would only cover visible short-wave infrared; the ability to detect longer wavelengths, such as mid- and long-wave infrared, is limited because they are restricted by the band gap of the bulk material. In this paper, a novel photodetector based on the synergistic effect of PbS CQDs and bismuth telluride (Bi2Te3) was developed for the detection of a mid-wave infrared band at room temperature. The device demonstrated good performance in the visible-near infrared band (i.e., between 660 and 850 nm) with detectivity of 1.6 × 1010 Jones at room temperature. It also exhibited photoelectric response in the mid-wave infrared band (i.e., between 4.6 and 5.1 μm). The facile fabrication process and excellent performance (with a response of up to 5.1 μm) of the hybrid Bi2Te3/PbS CQDS photodetector are highly attractive for many important applications that require high sensitivity and broadband light detection.