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Human activities lead to an increase in greenhouse gases in the environment, among which carbon dioxide (CO2) is one of the most prominent, giving rise to global warming and climate change. Climate change, along with the resulting environmental degradation, is one of the most challenging difficulties faced by humanity in the twenty-first century. The forest ecosystem, with plants being its most important component, plays a pivotal role in regulating climate. Carbon sequestration and oxygen release (CSOR) by plants are major ecological service functions that play an important role in mitigating the negative impacts of the greenhouse effect and help to achieve carbon peaking and neutrality. The CSOR of mulberry (Morus spp.), a species of economic and ecological significance, is not yet understood. Six mulberry tree varieties were selected to evaluate their CSOR potential during summer. We took into consideration whole-plant diurnal assimilation amounts (P), carbon sequestration per unit leaf area (WCO2), oxygen release per unit leaf area (WO2), carbon sequestration per unit land area (PCO2), and oxygen release per unit land area (PO2). Zhongsang 1302 showed the greatest potential for CSOR among the six mulberry varieties. The PCO2 value of the Zhongsang 1302 variety was 1531.84 g·m−2 during summer, followed by Suhu 16 (1380.12 g·m−2), Husang 32 (1005.63 g·m−2), Zhongsang 9703 (990.01 g·m−2), Yu 711 (940.43 g·m−2), and Jin 10 (848.29 g·m−2). Moreover, the Pearson correlation and path analyses showed that photosynthetic rate (PN) and leaf area index (LAI) mainly affect the overall CSOR potential in mulberry. These findings not only enrich theoretical research on CSOR in mulberry, but also serve as an important reference for the use of different mulberry tree varieties in improving climate conditions and achieving carbon peaking and neutrality. [ABSTRACT FROM AUTHOR]

One of the main challenges most organic photodiodes (OPDs) facing is to overcome the traditional trade‐off between ultralow dark current and high responsivity (R) in existing research. Here, van der Waals multilayer OPD based on water transfer printing method, termed hybrid bulk‐heterojunction (BHJ)/planar‐heterojunction (PHJ) (B‐PHJ) framework, is constructed making certain the high‐quality interface and novel two‐phase energy band alignment between the active and barrier layer with noise suppression and photovoltaic complement simultaneously. The prepared OPD exhibits the combined advantages of ultralow dark current (0.2 nA cm−2 at −1 V) and high responsivity (0.49 A W−1 at 850 nm). As a result, these superimposed effects enable the device to feature a superior liner dynamic range (LDR) of 210 dB and a specific detectivity of 1014 Jones to address the conventional responsivity‐noise trade‐off. The results reveal that the balance dynamics of charge transfer and charge blocking in van der Waals hybrid two‐phase framework OPD, may inspire the development of next OPDs. Finally, its diverse practical application potential is demonstrated through long‐distance misaligned photoplethysmography (PPG) measurement. [ABSTRACT FROM AUTHOR]

The human retina is able to extract key feature information from a large amount of redundant visual information, which is the basis for efficient information processing in the human visual system. However, current retina‐inspired photonic synaptic devices lack fast noise filtering capabilities, limiting the speed of image preprocessing in neuromorphic visual systems. Here, a photonic synaptic transistor (PST) based on graphene/organic heterojunction that exhibits high photosensitivity and optically tunable synaptic characteristics from visible to near‐infrared (488–1310 nm) is demonstrated. The PST enables light‐intensity‐controlled memory‐free and long‐memory mode switching, allowing to achieve fast image noise filtering in a PST‐based vision sensor (processing times as low as 30 ms). In addition, image recognition in an artificial neural network connected by the PST, and the efficiency and accuracy of image recognition can be significantly improved by performing image noise filtering at the front‐end is demonstrated. This work provides the potential to improve the information processing speed of bio‐inspired neuromorphic visual systems and contribute to the development of machine vision applications. [ABSTRACT FROM AUTHOR]

Virus-induced gene silencing (VIGS) is an RNA-mediated reverse genetics technique that has become an effective tool to investigate gene function in plants. Cotton is one of the most important economic crops globally. In the past decade, VIGS has been successfully applied in cotton functional genomic studies, including those examining abiotic and biotic stress responses and vegetative and reproductive development. This article summarizes the traditional vectors used in the cotton VIGS system, the visible markers used for endogenous gene silencing, the applications of VIGS in cotton functional genomics, and the limitations of VIGS and how they can be addressed in cotton. [ABSTRACT FROM AUTHOR]

2D materials provide an effective strategy for the construction of fast‐responsive and highly sensitive Schottky heterojunction devices. However, the strong Fermi pinning at the contact between bulk metallic electrodes and 2D semiconductor materials greatly hinders the wide application of such devices in optoelectronics. Herein, a self‐powered photodetector with high performance is fabricated based on an all‐2D van der Waals (vdWs) heterojunction composed of metallic 2H‐NbSe2 and semiconducting MoSe2. Benefiting from the strong built‐in electric field, the device exhibits a high rectification ratio of 2.1 × 103. Furthermore, the photovoltaic effect can be observed in a broad spectrum ranging from 405 to 980 nm without external voltage, where a maximum responsivity of 64.92 A W−1, a maximum specific detectivity of 2.39 × 1014 Jones, and a large on–off current ratio >105 are obtained at 650 nm. Simultaneously, the efficient charge separation at the high‐quality heterointerface of NbSe2/MoSe2 results in a fast response/recovery time of 180/80 µs. This work demonstrates the promising potential of the 2D metallic NbSe2 as an electrode forming a Schottky heterojunction to realize a high‐performance broadband photodetector for near‐infrared communication. [ABSTRACT FROM AUTHOR]

Mimicking the real‐time sensing and processing capabilities of human retina opens up a promising pathway for achieving vision chips with high‐efficient image processing. The development of retina‐inspired vision chip also requires hardware with high sensitivity, fast image capture, and the ability to sense under various lighting conditions. Herein, a high‐performance phototransistor based on graphene/organic heterojunction is demonstrated with a superior responsivity (2.86 × 106 A W−1), an outstanding respond speed (rise time/fall time is 20 µs/8.4 ms), and a remarkable detectivity (1.47 × 1014 Jones) at 650 nm. The phototransistor combines weak‐light detection capability (minimum detectable light intensity down to 2.8 nW cm−2) with gate‐tunable bi‐directional photoresponse capable of simultaneously sensing and processing visual images for light intensities ranging over six orders magnitude (10–107nW cm−2). Moreover, the phototransistor also exhibits an intriguing feature undiscovered in other retina‐inspired devices, namely that it can real‐time monitor the human pulse signal and heart rate by using photoplethysmography technology, and the measured heart rate error is only 0.87% compared with a commercially available sensor. This study paves the way for the development of low‐light and bio‐signal sensitive artificial retinas in the future. [ABSTRACT FROM AUTHOR]

Quantitative analyses of synthetic polymers were accomplished using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS). Many factors have hindered the development of quantitative measurement of polymers via MALDI TOF MS, e.g., laser power, matrix, cation salt, and cocrystallization. By probing the optimal conditions, two sets of polymers were studied. Fair repeatability of the samples ensures acceptable results. In set 1, two poly(ethylene glycols) with different end groups showed equal desorption/ionization efficiencies. Two synthetic polymers in set 2 with different chemical properties resulted in different MALDI responses. Good linearity was achieved by plotting the relationship between the sample concentration ratio and the total signal intensity ratio in both sets.

Optoelectronic synaptic devices, which combine the functions of photosensitivity and information processing, are essential for the development of artificial visual perception systems. Nevertheless, improving the paired pulse facilitation (PPF) index of optoelectronic synaptic devices, which is an urgent problem in the construction of high‐precision artificial visual perception systems, has received less attention so far. Herein, a light‐stimulated synaptic transistor (LSST) device with an ultra‐high PPF index (≈196%) is presented by introducing an ultra‐thin carrier regulator layer hexagonal boron nitride (h‐BN) into a classic graphene‐based hybrid transistor frame (graphene/CsPbBr3 quantum dots). Crucially, analysis of the rate‐limiting effect of h‐BN on photogenerated carriers reveals the mechanism behind the LSST ultra‐high PPF index. Furthermore, a two‐layer artificial neural network connected by LSST devices demonstrate ≈91.5% recognition accuracy of handwritten digits. This work provides an effective method for constructing artificial visual perception systems using a hybrid transistor frame in the future. [ABSTRACT FROM AUTHOR]

This paper describes experience with the sequencing of synthetic segment peptides of gp41 which are used in trimeric peptides as potential peptide-based vaccines and as inhibitors to mimic the fusion state of gp41 in HIV infection using ESI/CID-FT-ICR MS. All b and y″ series ions are found in the CID spectra and the mass difference between the calculated and observed results is very slight. FT-ICR MS again shows its power in peptide sequencing, successfully helping us obtain the sequence of an unknown peptide. [ABSTRACT FROM AUTHOR]

Simple Summary: The Chinese cordyceps is a valuable parasitic Ophiocordyceps sinensis fungus–Thitarodes/Hepialus larva complex. In view of culturing this complex, a method for the artificial rearing of the Thitarodes/Hepialus ghost moth hosts was established. Deterioration of the host insect population and low mummification rates in infected larvae constrain effective cultivation. Hybridization of Thitarodes/Hepialus populations may overcome this problem. Thitarodes shambalaensis and Thitarodes sp. were inbred or hybridized, and the biological parameters, larval sensitivity to the fungal infection and mitochondrial genomes of the resulting populations were investigated. Hybridization of T. shambalaensis and Thitarodes sp. allowed producing a new generation. One hybrid population (T. shambalaensis females mated with Thitarodes sp. males) showed increased population growth as compared with the parental Thitarodes sp. population. The sensitivity of the inbred larval populations to four fungal isolates of O. sinensis differed. The complete mitochondrial genomes of T. shambalaensis, Thitarodes sp. and the hybrid population were 15,612 bp, 15,389 bp and 15,496 bp in length, respectively. A + T-rich regions were variable in sizes and repetitive sequences. The hybrid population was located in the same clade with T. shambalaensis, implying the maternal inheritance of mitochondrial DNA. The Chinese cordyceps, a parasitic Ophiocordyceps sinensis fungus–Thitarodes/Hepialus larva complex, is a valuable biological resource endemic to the Tibetan Plateau. Protection of the Plateau environment and huge market demand make it necessary to culture this complex in an artificial system. A method for the large-scale artificial rearing of the Thitarodes/Hepialus insect host has been established. However, the deterioration of the insect rearing population and low mummification of the infected larvae by the fungus constrain effective commercial cultivation. Hybridization of Thitarodes/Hepialus populations may be needed to overcome this problem. The species T. shambalaensis (GG♂ × GG♀) and an undescribed Thitarodes species (SD♂ × SD♀) were inbred or hybridized to evaluate the biological parameters, larval sensitivity to the fungal infection and mitochondrial genomes of the resulting populations. The two parental Thitarodes species exhibited significant differences in adult fresh weights and body lengths but not in pupal emergence rates. Hybridization of T. shambalaensis and Thitarodes sp. allowed producing a new generation. The SD♂ × GG♀ population showed a higher population trend index than the SD♂ × SD♀ population, implying increased population growth compared with the male parent. The sensitivity of the inbred larval populations to four fungal isolates of O. sinensis also differed. This provides possibilities to create Thitarodes/Hepialus populations with increased growth potential for the improved artificial production of the insect hosts. The mitochondrial genomes of GG♂ × GG♀, SD♂ × SD♀ and SD♂ × GG♀ were 15,612 bp, 15,389 bp and 15,496 bp in length, with an A + T content of 80.92%, 82.35% and 80.87%, respectively. The A + T-rich region contains 787 bp with two 114 bp repetitive sequences, 554 bp without repetitive sequences and 673 bp without repetitive sequences in GG♂ × GG♀, SD♂ × SD♀ and SD♂ × GG♀, respectively. The hybrid population (SD♂ × GG♀) was located in the same clade with GG♂ × GG♀, based on the phylogenetic tree constructed by 13 PCGs, implying the maternal inheritance of mitochondrial DNA. [ABSTRACT FROM AUTHOR]

Electron impact-induced fragmentations of isomeric dodecen-1-ols were investigated using mass-analysed ion kinetic energy (MIKE) spectrometry and high-resolution data. The principal fragmentation pathways of the positional isomers studied are dominated by the CC double bond and involve migration and radical-site rearrangements along the carbon chain with the aid of consecutive rearrangements of hydrogen atoms. [ABSTRACT FROM AUTHOR]

Mass spectra of eight new 1,2,3,5-polysubstituted pyrroles were studied by methods of electron impact, mass-analysed ion kinetic energy and high-resolution data. It has been found that five-membered or six-membered cyclic ions were formed and other rearrangement ions were observed in the mass spectra. [ABSTRACT FROM AUTHOR]

The mass spectra of novel estra derivatives of amino acids and peptides were studied using electron impact and fast atom bombardment ionization, high-resolution data and mass-analysed ion kinetic energy spectrometry. The characteristic peaks of the basic nucleus of estrogenic steroids, the amino acid sequence of the peptide chain and partial skeletal rearrangement of some of these compounds were observed. [ABSTRACT FROM AUTHOR]

An analytical method based on matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) has been applied to provide information on the structure of a copolymer, e.g., repeat unit and end group. Seven conjugated polymers, which have been demonstrated as the active component in blue light-emitting diodes, were synthesized through Suzuki polycondensation reaction in the presence of Pd(PPh3)4 catalyst. Their molecular weights were obtained using gel permeation chromatography analysis. MALDI-TOF MS was used to investigate the structure information in detail. The proposed end-group structures were confirmed by the identity between the observed and the simulated isotopic distribution of each polymer. The results demonstrate that these synthetic polymers possess various end groups and even contain macrocycles. The catalyst Pd(PPh3)4 was found to introduce phenyl end groups via aryl-aryl exchange between the catalytic palladium intermediate and the triphenylphosphine ligand. All these results are based on the analysis of the mass spectrum data, which suggests that MALDI-TOF MS is an extraordinarily strong tool in synthetic polymer structure analysis.