Opposite Shifts Research Articles

Pressure-induced phase transition from monomers to dimers in liquid crystals

ABSTRACT The crystal structures of liquid crystals, particularly various oligomers, have garnered significant attention, laying the groundwork for developing new materials and devices. Here, we demonstrate pressure plays a crucial role in the structure of liquid crystals. High-pressure Raman and photoluminescence spectra were on 5CB (4-cyano-4’−pentylbiphenyl) liquid crystal. Upon compression, the appearance of prominent fluorescence peaks suggests a phase transition. The Raman peaks, reflecting the C–H and C≡N bonds, exhibit splitting at a pressure of 3.2 GPa, further confirming the pressure-induced phase transition. The splitting is consistent with earlier calculations on the stretching vibration of the C≡N bond for various oligomers and indicates a phase transition from monomers to dimers in 5CB liquid crystal. The opposite shifts in Raman modes under pressure, specifically the blue-shift of C–H bonds and the red-shift of C≡N bonds, indicate that pressure enhances intermolecular interactions and leads to conjugation between the electrons on the C≡N bonds and the C–H bonds, resulting in dimer formation. Our findings not only reveal a novel strategy for producing oligomers in liquid crystals through the application of high pressure but also highlight that Raman spectroscopy is a valid, non-contact method for investigating the mechanisms of oligomerization.

Microbiota responses to mutations affecting NO homeostasis in Arabidopsis thaliana.

Interactions between plants and microorganisms are pivotal for plant growth and productivity. Several plant molecular mechanisms that shape these microbial communities have been identified. However, the importance of nitric oxide (NO) produced by plants for the associated microbiota remains elusive. Using Arabidopsis thaliana isogenic mutants overproducing NO (nox1, NO overexpression) or down-producing NO (i.e. nia1nia2 impaired in the expression of both nitrate reductases NR1/NIA1 and NR2/NIA2; the 35s::GSNOR1 line overexpressing nitrosoglutathione reductase (GSNOR) and 35s::AHB1 line overexpressing haemoglobin 1 (AHB1)), we investigated how altered NO homeostasis affects microbial communities in the rhizosphere and in the roots, soil microbial activity and soil metabolites. We show that the rhizosphere microbiome was affected by the mutant genotypes, with the nox1 and nia1nia2 mutants causing opposite shifts in bacterial and fungal communities compared with the wild-type (WT) Col-0 in the rhizosphere and roots, respectively. These mutants also exhibited distinctive soil metabolite profiles than those from the other genotypes while soil microbial activity did not differ between the mutants and the WT Col-0. Our findings support our hypothesis that changes in NO production by plants can influence the plant microbiome composition with differential effects between fungal and bacterial communities.

Enzyme stabilisation due to incorporation of a fluorinated non-natural amino acid at the protein surface

We have previously engineered E. coli transketolase (TK) enzyme variants that accept new substrates such as aliphatic or aromatic aldehydes, and also with improved thermal stability. Irreversible aggregation is the primary mechanism of deactivation for TK in the buffers used for biocatalysis, and so we were interested in determining the extent to which this remains true in more complex media, crude cell lysates or even in vivo. Such understanding would better guide future protein engineering efforts. NMR offers a potential approach to probe protein structure changes, aggregation, and diffusion, and19F-labelled amino acids are a useful NMR probe for complex systems with little or no background signal from the rest of the protein or their environment. Here we labelled E. coli TK with two different19F probes, trifluoromethyl-L-phenylalanine (tfm-Phe), and 4-fluoro phenylalanine (4 F-Phe), through site specific non-natural amino acid incorporation. We targeted them to residue K316, a highly solvent exposed site located at the furthest point from the enzyme active sites. Characterisation of the19F-labelled TK variants revealed surprising effects of these mutations on stability, and to some extent on activity. While variant TK-tfm-Phe led to a 7.5 °C increase in the thermal transition midpoint (Tm) for denaturation, the TK-4 F-Phe variant largely abolished the aggregation of the enzyme when incubated at 50 °C19. F-NMR revealed different behaviours in response to temperature increases for the two TK variants, displaying opposite temperature gradient chemical shifts, and diverging motion regimes, suggesting that the mutations affected differently both the local environment at this site, and its temperature-induced dynamics. A similar incubation of TK at 40–55 °C is also known to induce higher cofactor-binding affinities, leading to an apparent heat activation under low cofactor concentration conditions. We have hypothesised previously that a heat-inducible conformational change in TK leads to this effect1. H-NMR revealed a temperature-dependent re-structuring of methyl groups, also at 30–50 °C, which may be linked to the heat activation. While our kinetic studies were not expected to observe the heat activation event due to the high cofactor concentrations used, this was not the case for TK-4 F-Phe, which did appear to heat activate slightly at 45 °C. This implied that the mutations at K316 could influence cofactor-binding, despite their location at 47 Å from either active site. Such long-distance effects of mutations are not unprecedented, and indeed we have previously shown how distant mutations can influence active-site loop stability and function in TK, mediated via dynamically coupled networks of residues. Molecular dynamics simulations of the two19F containing variants similarly revealed networks of residues that could couple the changes in dynamics at residue K316, through to changes in active site dynamics. These results independently highlight the sensitivity of active-site function to distant mutations coupled through correlated dynamic networks of residues. They also highlight the potential influence of surface-incorporated probes on protein stability and function, and the need to characterise them well prior to further studies.

Assessing energy efficiency and its dynamic changes in the water sector integrating heterogeneity and carbon emissions

Enhancing the energy performance of water utilities is a critical step towards achieving a net-zero carbon industry. Traditional energy performance assessments in the water industry often overlook heterogeneity among water companies and fail to account for changes in energy efficiency (EE) over time. To address these shortcomings, this research employs Stochastic Frontier Analysis (SFA) techniques to assess energy performance of two types of water companies such as Water and Sewerage Companies (WaSCs) and Water-only Companies (WoCs) within a single energy frontier model. Empirical analysis of water companies in England and Wales reveals an average EE score of 0.940 over the 2010–2020 period, suggesting a 6% energy-saving potential. English and Welsh water industry exhibited an overall 0.3% annual improvement in energy productivity change (EPC). This improvement was primarily attributed to efficiency changes (average 1.005), which offset the negative shift in technology change (average 0.998), while the scale effect remained negligible (average 1.000). WaSCs experienced a slight increase in EPC, with an average value of 1.018, indicating an improvement in energy productivity. In contrast, WoCs exhibited a decrease in EPC, with an average value of 0.989, suggesting a decline in energy productivity. These disparities were due to opposite shifts in the efficient production frontier; WaSCs had a positive shift (average 1.012), while WoCs had a negative shift (average 0.984). The study also highlights the impact of regulatory policies on energy performance. The 2009 price review involved modest improvements (average EPC = 1.013), while the 2014 price review yielded unfavorable results (average EPC = 0.993), emphasizing the need for long-term policies to facilitate sector-wide transformation towards carbon neutrality.

Sub-picosecond, strain-tunable, polarization-selective optical switching via anisotropic exciton dynamics in quasi-1D ZrSe3

In cutting-edge optical technologies, polarization is a key for encoding and transmitting vast information, highlighting the importance of selectively switching and modulating polarized light. Recently, anisotropic two-dimensional materials have emerged for ultrafast switching of polarization-multiplexed optical signals, but face challenges with low polarization ratios and limited spectral ranges. Here, we apply strain to quasi-one-dimensional layered ZrSe3 to enhance polarization selectivity and tune operational energies in ultrafast all-optical switching. Initially, transient absorption on unstrained ZrSe3 reveals a sub-picosecond switching response in polarization along a specific crystal axis, attributed to shifting-recovery dynamics of an anisotropic exciton. However, its polarization selectivity is weakened by a slow non-excitonic response in the perpendicular polarization. To overcome this limitation, we apply strain to ZrSe3 by bending its flexible substrate. The compressive strain spectrally decouples the excitonic and non-excitonic components, doubling the polarization selectivity of the sub-picosecond switching and tripling it compared to that in the tensile-strained ZrSe3. It also effectively tunes the switching energy at a shift rate of ~93 meV %-1. This strain-tunable switching is repeatable, reversible, and robustly maintains the sub-picosecond operation. First-principles calculations reveal that the strain control is enabled by momentum- and band-dependent modulations of the electronic band structure, causing opposite shifts in the excitonic and non-excitonic transitions. Our findings offer a novel approach for high-performance, wavelength-tunable, polarization-selective ultrafast optical switching.

Distinct chemical degradation pathways of AAV1 and AAV8 under thermal stress conditions revealed by analytical anion exchange chromatography and LC-MS-based peptide mapping

Adeno-associated virus (AAV)-based gene therapy is experiencing a rapid growth in the field of medicine and holds great promise in combating a wide range of human diseases. For successful development of AAV-based products, comprehensive thermal stability studies are often required to establish storage conditions and shelf life. However, as a relatively new modality, limited studies have been reported to elucidate the chemical degradation pathways of AAV products under thermal stress conditions. In this study, we first presented an intriguing difference in charge profile shift between thermally stressed AAV8 and AAV1 capsids when analyzed by anion exchange chromatography. Subsequently, a novel and robust peptide mapping protocol was developed and applied to elucidate the underlying chemical degradation pathways of thermally stressed AAV8 and AAV1. Compared to the conventional therapeutic proteins, the unique structure of AAV capsids also led to some key differences in how modifications at specific sites may impact the overall charge properties. Finally, despite the high sequency identity, the analysis revealed that the opposite charge profile shifts between thermally stressed AAV8 and AAV1 could be mainly attributed to a single modification unique to each serotype.

Glucocorticoid receptor controls atopic dermatitis inflammation via functional interactions with P63 and autocrine signaling in epidermal keratinocytes

Atopic dermatitis (AD), a prevalent chronic inflammatory disease with multifactorial etiology, features epidermal barrier defects and immune overactivation. Synthetic glucocorticoids (GCs) are widely prescribed for treating AD due to their anti-inflammatory actions; however, mechanisms are incompletely understood. Defective local GC signaling due to decreased production of endogenous ligand and/or GC receptor (GR) levels was reported in prevalent inflammatory skin disorders; whether this is a consequence or contributing factor to AD pathology is unclear. To identify the chromatin-bound cell-type-specific GR protein interactome in keratinocytes, we used rapid immunoprecipitation of endogenous proteins and mass spectrometry identifying 145 interactors that increased upon dexamethasone treatment. GR-interacting proteins were enriched in p53/p63 signaling, including epidermal transcription factors with critical roles in AD pathology. Previous analyses indicating mirrored AD-like phenotypes between P63 overexpression and GR loss in epidermis, and our data show an intricate relationship between these transcription factors in human keratinocytes, identifying TP63 as a direct GR target. Dexamethasone treatment counteracted transcriptional up-regulation of inflammatory markers by IL4/IL13, known to mimic AD, causing opposite shifts in GR and P63 genomic binding. Indeed, IL4/IL13 decreased GR and increased P63 levels in cultured keratinocytes and human epidermal equivalents (HEE), consistent with GR down-regulation and increased P63 expression in AD lesions vs normal skin. Moreover, GR knockdown (GRKD) resulted in constitutive increases in P63, phospho-P38 and S100A9, IL6, and IL33. Also, GRKD culture supernatants showed increased autocrine production of TH2-/TH1-/TH17-TH22-associated factors including IL4, CXCL10, CXCL11, and CXCL8. GRKD HEEs showed AD-like features including hyperplasia and abnormal differentiation, resembling phenotypes observed with GR antagonist or IL4/IL13 treatment. The simultaneous GR/P63 knockdown partially reversed constitutive up-regulation of inflammatory genes in GRKD. In summary, our data support a causative role for GR loss in AD pathogenesis via functional interactions with P63 and autocrine signaling in epidermal keratinocytes.

Enhancing Layer-Engineered Interlayer Exciton Emission and Valley Polarization in van der Waals Heterostructures via Strain.

Layer-engineered interlayer excitons from heterostructures of transition-metal dichalcogenides (TMDCs) exhibit a rich variety of emissive states and intriguing valley spin-selection rules, the effective modulation of which is crucial for excitonic physics and related device applications. Strain or high pressure provides the possibility to tune the energy of the interlayer excitons; however, the reported emission intensity is substantially quenched, which greatly limits their practical application in optoelectronic devices. Here, via applying uniaxial strain based on polyvinyl alcohol (PVA) encapsulation technique, we report enhanced layer-engineered interlayer exciton emission intensity with largely modulated emission energy in WSe2/WS2 heterobilayer and heterotrilayer. Both momentum-direct and momentum-indirect interlayer excitons were observed, and their emission energies show an opposite shift tendency upon applied strain, which agrees with our DFT calculations. We further demonstrate that intralayer and interlayer exciton states with low phonon interactions can be modulated through the mechanical strain applied to the PVA substrate at low temperatures. Due to strain-induced breaking of the 3-fold rotational symmetry, we observe the enhanced valley polarization of interlayer excitons. Our study contributes to the understanding and modulation of the optical properties of interlayer excitons, which could be exploited for optoelectronic device applications.

From heterosis to outbreeding depression: genotype-by-environment interaction shifts hybrid fitness in opposite directions.

In F1 hybrids, phenotypic values are expected to be near the parental means under additive effects or close to one parent under dominance. However, F1 traits can fall outside the parental range, and outbreeding depression occurs when inferior fitness is observed in hybrids. Another possible outcome is heterosis, a phenomenon that interspecific hybrids or intraspecific crossbred F1s exhibit improved fitness compared to both parental species or strains. As an application of heterosis, hybrids between channel catfish females and blue catfish males are superior in feed conversion efficiency, carcass yield, and harvestability. Over 20 years of hybrid catfish production in experimental settings and farming practices generated abundant phenotypic data, making it an ideal system to investigate heterosis. In this study, we characterized fitness in terms of growth and survival longitudinally, revealing environment-dependent heterosis. In ponds, hybrids outgrow both parents due to an extra rapid growth phase of 2-4 months in year 2. This bimodal growth pattern is unique to F1 hybrids in pond culture environments only. In sharp contrast, the same genetic types cultured in tanks display outbreeding depression, where hybrids perform poorly, while channel catfish demonstrate superiority in growth throughout development. Our findings represent the first example, known to the authors, of opposite fitness shifts in response to environmental changes in interspecific vertebrate hybrids, suggesting a broader fitness landscape for F1 hybrids. Future genomic studies based on this experiment will help understand genome-environment interaction in shaping the F1 progeny fitness in the scenario of environment-dependent heterosis and outbreeding depression.

Chemical bond reorganization in intramolecular proton transfer revealed by ultrafast X-ray photoelectron spectroscopy

Time-resolved X-ray photoelectron spectroscopy (TR-XPS) is used in a simulation study to monitor the excited state intramolecular proton transfer between oxygen and nitrogen atoms in 2-(iminomethyl)phenol. Real-time monitoring of the chemical bond breaking and forming processes is obtained through the time evolution of excited-state chemical shifts. By employing individual atomic probes of the proton donor and acceptor atoms, we predict distinct signals with opposite chemical shifts of the donor and acceptor groups during proton transfer. Details of the ultrafast bond breaking and forming dynamics are revealed by extending the classical electron spectroscopy chemical analysis to real time. Through a comparison with simulated time-resolved photoelectron spectroscopy at the valence level, the distinct advantage of TR-XPS is demonstrated thanks to its atom specificity.

How demand-side management can shape electricity generation capacity planning

Forward-looking strategies for Demand Side Management (DSM) can accelerate the clean energy transition and reduce carbon emissions if electricity load can be shaped to be better matched to the hourly availability of renewable resources. Time-varying rates are increasingly used to motivate load shifting, capitalizing on the increasing size of loads that can be easily shifted, such as electric vehicle charging and electric heat pumps. This study analyzes the hourly availability of current and renewable resources for two representative electricity grids in the USA. While many demand-management programs are currently designed to shift load to nighttime when demand is low, to use low-cost PV the opposite shift into daytime will be preferred. Given that investments in electricity generation capacity shape the grid for decades, generation capacity planning should proactively anticipate how DSM programs (and associated load shapes) will change as the generation mix changes. These future load shapes determine the optimal resources to be acquired and can be modified by DSM to facilitate variable renewable integration. Ongoing regulatory proceedings in Colorado are described as a case study for an existing decision-making process.

Reappraisal of serum retinol-binding protein as a surrogate marker for retinol and discovery of a novel retinol estimation formula

Background & AimsSerum retinol (ROH) is commonly used for population level assessment of vitamin A status. High-performance liquid chromatography (HPLC) is considered most accurate method for measuring ROH. However, with the technical difficulty of using HPLC for routine assays, serum retinol-binding protein (RBP) measured by immunological assays is expected to be a surrogate marker for ROH, with reports of a close correlation between serum RBP and ROH. Nevertheless, RBP is not commonly tested to assess vitamin A status with concerns over RBP alterations under various physiopathological conditions. Thus, we reappraised the extent to which RBP could be used as a surrogate marker in representative disorders that alter serum RBP levels. As a related marker, diagnostic utility of transthyretin (TTR) was also evaluated. MethodsTo evaluate the reliability of ROH and RBP assays, specimen stability was assessed in terms of (1) storage at 25, 4, −20, and −80 ºC for 1−28 days, (2) five-cycle freeze-thawing, and (3) fluorescent light exposure for 1−14 days. Sources of variation (sex, age, body mass index [BMI], and drinking habits) and reference intervals for ROH, RBP, and TTR were determined in 617 well-defined healthy individuals. To investigate the influence of disorders that affect serum RBP, patients with five diagnostic groups were enrolled: 26 with chronic kidney disease (CKD); 13 with various malignancies in advanced stages (AdM), 12 with acute bacterial infections (ABI), 6 with liver cirrhosis (LC), and 26 with simple obesity (BMI ≥ 27 kg/m2). ResultsThe stability of RBP and ROH in serum was confirmed under all conditions. In healthy individuals, serum ROH, RBP, and TTR were appreciably high in males with a slight increase in proportion to age and BMI. The major-axis regression line between RBP (x) and ROH (y) in healthy individuals was y = x, with a correlation coefficient of 0.986. In the LC, AdM, and ABI groups, similar strong correlations were observed; however, the regression lines were shifted slightly rightward from the healthy group line, indicating a positive bias in estimating ROH. Interestingly, the same analyses between TTR and ROH revealed similar strong linear relationships in all groups; however, the regression line of each group showed a leftward (opposite) shift from the healthy group line. Based on these observations, we developed a novel regression model composed of RBP and TTR, which proved to be accurate in estimating ROH, even under these pathological conditions. ConclusionsThe perfect RBP-ROH correlation in healthy individuals indicates the utility of RPB as a surrogate marker for ROH. Nevertheless, under RBP-altered conditions, a slight overestimation of ROH is inevitable. However, when the TTR was tested together, the bias can be corrected almost perfectly using the novel ROH estimation formula comprising RBP and TTR.

Complementarity in which-path resonant Auger scattering

Different types of Young's double-slit experiments contain a significant amount of both particle and wave information running from full-particle to full-wave knowledge depending on the experimental conditions. We study the Young's double-slit interference in resonant Auger scattering from homonuclear diatomic molecules where opposite Doppler shifts for the dissociating atomic slits provide path information. Different quantitative formulation of Bohr's complementarity principle—path information vs interference—is applied to two types of resonant Auger scattering experiments, with fixed-in-space and randomly oriented molecules. Special attention is paid to the orientational dephasing in conventional Auger experiments with randomly oriented molecules. Our quantitative formulation of the complementarity is compared with the formulation made earlier by Greenberger and Yasin [D. M. Greenberger and A. Yasin, ]. Published by the American Physical Society 2024

Polysaccharide from Atractylodes macrocephala Koidz Binding with Zinc Oxide Nanoparticles as a Novel Mucosal Immune Adjuvant for H9N2 Inactivated Vaccine.

H9N2 avian influenza poses a significant public health risk, necessitating effective vaccines for mass immunization. Oral inactivated vaccines offer advantages like the ease of administration, but their efficacy often requires enhancement through mucosal adjuvants. In a previous study, we established a novel complex of polysaccharide from Atractylodes macrocephala Koidz binding with zinc oxide nanoparticles (AMP-ZnONPs) and preliminarily demonstrated its immune-enhancing function. This work aimed to evaluate the efficacy of AMP-ZnONPs as adjuvants in an oral H9N2-inactivated vaccine and the vaccine's impact on intestinal mucosal immunity. In this study, mice were orally vaccinated on days 0 and 14 after adapting to the environment. AMP-ZnONPs significantly improved HI titers, the levels of specific IgG, IgG1 and IgG2a in serum and sIgA in intestinal lavage fluid; increased the number of B-1 and B-2 cells and dendritic cell populations; and enhanced the mRNA expression of intestinal homing factors and immune-related cytokines. Interestingly, AMP-ZnONPs were more likely to affect B-1 cells than B-2 cells. AMP-ZnONPs showed mucosal immune enhancement that was comparable to positive control (cholera toxin, CT), but not to the side effect of weight loss caused by CT. Compared to the whole-inactivated H9N2 virus (WIV) group, the WIV + AMP-ZnONP and WIV + CT groups exhibited opposite shifts in gut microbial abundance. AMP-ZnONPs serve as an effective and safe mucosal adjuvant for oral WIV, improving cellular, humoral and mucosal immunity and microbiota in the gastrointestinal tract, avoiding the related undesired effects of CT.

Angularly Cascaded Long-Period Fiber Grating for Curvature and Temperature Detection.

A high-sensitivity curvature sensor with dual-parameter measurement ability based on angularly cascaded long-period fiber grating (AC-LPFG) is proposed and experimentally demonstrated, which consists of two titled LPFGs (TLPFGs) with different tilt angles and the same grating period. AC-LPFG was fabricated by using a deep ultraviolet laser and an amplitude-mask in our laboratory. The experimental results show that simultaneous measurement of curvature and temperature can be achieved by monitoring the wavelengths of two resonant peaks for different TLPFGs. The two peaks show opposite shifts with increasing curvature and has a maximum curvature sensitivity of 16.392 nm/m-1. With the advantages of low cost, high sensitivity, and dual-parameter measurements, our sensor has more potential for engineering applications.

Increasing innovative activity at Ukrainian industrial enterprises through technology transfer

The article examines measures of step-by-step promotion of innovations at industrial enterprises of Ukraine. Economic factors hindering the implementation of new technologies at enterprises are highlighted. This is caused primarily by the fact that during the global economic crisis, enterprises and industries that actively implement and use innovative technologies are competitive. At the same time, Ukraine continues to develop as a country with a high share of raw materials industries, and innovative development has not become one of the main signs of the growth of the national economy. Although positive trends were observed for several years, they were mainly temporary in nature and were replaced by opposite shifts in the economy, which characterizes innovation processes in Ukraine as unstable and devoid of clear long-term incentives for innovative activity. In these conditions, there is a need to identify key problems that hinder the development of innovative activities of domestic enterprises, and to find ways to solve them. The implementation of a marketing strategy for the promotion of innovative projects at small and medium-sized industrial enterprises and the transfer process of innovations at large enterprises to gain their competitive advantages in domestic and foreign markets is substantiated. Emphasis is placed on the existing features of implementation in the conditions of digitalization of global business, which is confirmed by the construction of appropriate layouts and schemes. An overview was carried out to what extent all these technological innovations lead to deep and large-scale changes in the systemic character of economic (and not only economic) relations, reformatting of their very foundations and the emergence of new socio-economic institutions. Thus, the basis of modern relations is not only and not so much property relations, but the possibility of access to certain goods, resources, and information. Radical technological innovations to one degree or another affect and will increasingly affect the technologies of commercial operations, the role and forms of activity of their commercial intermediaries. The process of technology transfer to the real sector of the economy has been improved, which takes into account the joint refinement of innovative projects of innovators with enterprises that are potential bases of implementation, with the implementation of the activities of the Coordination Center.

Exploring the spillover effect and supply chain coordination in dual-channel green supply chains with blockchain-based sales platform

With the increasing consumer demand for environmentally friendly products, it has become crucial for manufacturers to effectively communicate their sustainability efforts. While the literature extensively examines the benefits of blockchain technology in facilitating informed decision making, little research has explored its cross-channel influence (spillover effect) on decisions in a dual-channel green supply chain. In this study, we investigate a green supply chain with a manufacturer operating a direct channel and making efforts to improve product greenness and a blockchain-based sales platform whose service has a spillover effect on consumer valuation of product greenness in the direct channel. Our findings indicate that, in an uncoordinated supply chain, the spillover effect adversely affects the platform but benefits the manufacturer, while it benefits both parties under coordination. This underscores the importance of supply chain coordination for the sales platform to capitalize on the spillover effect. Moreover, under coordination, variations in key parameters generally align product greenness with supply chain profitability. Finally, the spillover effect typically triggers a shift in demand from the platform to the direct channel, whereas a stronger consumer preference for the platform tends to drive the opposite shift in demand. Interestingly, when product greenness improvement is less costly and the blockchain cost is significant, the spillover effect can stimulate sales on both channels. And, when product greenness improvement is less costly and the blockchain cost is small, a stronger consumer preference for the platform can lead to a shift in demand from the platform to the direct channel.

The Impact of Changes in Sea Level and East Asian Monsoon on Sediment Transport on the Sunda Shelf Since the Last Deglaciation

AbstractThe Sunda Shelf plays a key role in the sedimentation of the southern South China Sea (SCS). However, the impact of past climate changes on sediment transfer to the Sunda Shelf and the southern SCS is still unresolved. Here, we present new data on grain size, clay mineralogy, and Sr‐Nd isotopes of three marine cores, river sediments, and surface sediments of the Sunda Shelf. The results indicate that clay fractions of the central Sunda Shelf and the Gulf of Thailand derived mainly from the Mekong River and the rivers of northern Thailand since the last deglaciation. Significant changes in sediment sources are observed at 7.5 cal ka BP. From 13.3 to 7.5 cal ka BP, sediments in the Gulf of Thailand mainly originated from the rivers of northern Thailand, with contributions from the Mekong River increasing after 7.5 cal ka BP. An opposite shift is observed in the central Sunda Shelf. Such variations in the spatial distribution result from a combination of sea level and East Asian monsoon effects. After 7.5 cal ka BP, less Mekong River sediments were transported southeastwards into the southern SCS, and more sediments were gradually trapped within the delta and transported in a southwesterly direction into the Gulf of Thailand due to intense East Asian winter monsoon, which forced a strong southwestward coastal current. Our results demonstrate the important impact of East Asian winter monsoon strengthening and sea level rise in the mid‐Holocene, which can change sediment sources and transport processes on the Sunda Shelf.

Photonic angle-of-arrival measurement of microwave signals using a triangular wave.

A novel, to the best of our knowledge, photonics-assisted approach for measuring the angle-of-arrival (AOA) of microwave signals with a large measurement range is proposed. The system utilizes a dual-drive Mach-Zehnder modulator (DDMZM) for signal modulation, followed by an optical filter for sideband selection. The dc port of the DDMZM is fed by a triangular wave to generate a pair of opposite frequency shifts. An intermediate frequency (IF) signal with a periodic phase jump is obtained after photodetection. The AOA of the incoming signals can be estimated by measuring the value of the phase jump. The key novelty of the proposed scheme lies in the application of a triangular wave to shift the frequency of optical signals, which introduces a periodic phase jump to the IF signal. The system incorporates only a single optical channel, largely reducing the system complexity. Experimental results show that an AOA measurement with a range of -70.8° to 70.8° is realized, with errors confined to within ±2°.

Multimaterial Additively Manufactured Transmissive Spin‐Decoupled Polarization‐Maintaining Metasurfaces

AbstractTaking advantage of multimaterial additive manufacturing, this work demonstrates a kind of polarization‐maintaining metasurface (MS) for spin‐decoupled beam shaping. The wavefronts of the two spin states, i.e., the left‐hand circular polarization (LHCP) and the right‐hand circular polarization (RHCP), can be independently manipulated while the output spin state remains the same as the input. The meta‐atom is implemented with dual‐polarized antennas at the top and the bottom with phase delay lines connecting them. The dual‐polarized antenna on the receiving side is fixed to receive the LHCP/RHCP incident waves, while the dual‐polarized transmitting antenna is rotated, providing the opposite phase shifts for the LHCP and RHCP. The absolute value of the phase shift is the same as the transmitting antenna's rotation angle. Meanwhile, varying the length of phase delay lines introduces 2π phase shifts for both LHCP and RHCP inputs. Thus, combining the two phase‐shifting degrees of freedom, the LHCP and RHCP wavefronts can be independently controlled while the polarization is not flipped after transmitting through the MS. One MS produces vortex beams with different topological charges for LHCP and RHCP. The other achieves spin‐decoupled focusing. The multilayered MSs are conveniently printed using multimaterial additive manufacturing without postprocessing.