Enhanced super-Heisenberg scaling precision by nonlinear coupling and postselection

In quantum precision metrology, the famous result of Heisenberg limit scaling as $1/N$ (with $N$ the number of probes) can be surpassed by considering nonlinear coupling measurement. In this work, we consider the most practice-relevant quadratic nonlinear coupling and show that the metrological precision can be enhanced from the $1/N^{\frac{3}{2}}$ super-Heisenberg scaling to $1/N^2$, by simply employing a pre- and post-selection (PPS) technique, but not using any expensive quantum resources such as quantum entangled state of probes.Comment: 6 pages, 4 figure

Quantum-coherence-free precision metrology by means of difference-signal amplification

The novel weak-value-amplification (WVA) scheme of precision metrology is deeply rooted in the quantum nature of destructive interference between the pre- and post-selection states. And, an alternative version, termed as joint WVA (JWVA), which employs the difference-signal from the post-selection accepted and rejected results, has been found possible to achieve even better sensitivity (two orders of magnitude higher) under some technical limitations (e.g. misalignment errors). In this work, after erasing the quantum coherence, we analyze the difference-signal amplification (DSA) technique, which serves as a classical counterpart of the JWVA, and show that similar amplification effect can be achieved. We obtain a simple expression for the amplified signal, carry out characterization of precision, and point out the optimal working regime. We also discuss how to implement the post-selection of a classical mixed state. The proposed classical DSA technique holds similar technical advantages of the JWVA and may find interesting applications in practice.Comment: 7pages, 5 figures. arXiv admin note: text overlap with arXiv:2207.0366

Factors Influencing Organic Food Purchase of Young Chinese Consumers

Organic food has drawn attention of more and more consumers. As a result, many researchers have attempted to explain the motivations and marketing issues relevant to the topic. The previous studies provide some conflicting results and could not produce a comprehensive understanding of organic food consumers in China. Given the present research, this paper attempts to conduct a comprehensive study of organic food consumption by examining a variety of factors influencing the consumption of organic food and provide some marketing implications through a survey of young consumers in a large metropolitan area in China. The results have shown that the revised TRA model has been successfully applied in this study. The research has concluded that “food safety”, “nutrition”, and “environmental friendly” are significant factors to impact the purchase of organic food while considering the demographical variables. In addition, the study found that consumers prefer vegetables, fruits, grain and beans, milk, meat and eggs to be organic, which are ranked according to the degree of preference. Moreover, the research suggests that the main barriers bringing about the gap between attitudes and behaviors are price, the distrust on certifications of organic food, and unavailability. These findings have implications for marketing communications to consumers and potentially for organic product development

Factors Influencing Organic Food Purchase of Young Chinese Consumers

Organic food has drawn attention of more and more consumers. As a result, many researchers have attempted to explain the motivations and marketing issues relevant to the topic. The previous studies provide some conflicting results and could not produce a comprehensive understanding of organic food consumers in China. Given the present research, this paper attempts to conduct a comprehensive study of organic food consumption by examining a variety of factors influencing the consumption of organic food and provide some marketing implications through a survey of young consumers in a large metropolitan area in China. The results have shown that the revised TRA model has been successfully applied in this study. The research has concluded that “food safety”, “nutrition”, and “environmental friendly” are significant factors to impact the purchase of organic food while considering the demographical variables. In addition, the study found that consumers prefer vegetables, fruits, grain and beans, milk, meat and eggs to be organic, which are ranked according to the degree of preference. Moreover, the research suggests that the main barriers bringing about the gap between attitudes and behaviors are price, the distrust on certifications of organic food, and unavailability. These findings have implications for marketing communications to consumers and potentially for organic product development

Factors Influencing Organic Food Purchase of Young Chinese Consumers

Organic food has drawn attention of more and more consumers. As a result, many researchers have attempted to explain the motivations and marketing issues relevant to the topic. The previous studies provide some conflicting results and could not produce a comprehensive understanding of organic food consumers in China. Given the present research, this paper attempts to conduct a comprehensive study of organic food consumption by examining a variety of factors influencing the consumption of organic food and provide some marketing implications through a survey of young consumers in a large metropolitan area in China. The results have shown that the revised TRA model has been successfully applied in this study. The research has concluded that “food safety”, “nutrition”, and “environmental friendly” are significant factors to impact the purchase of organic food while considering the demographical variables. In addition, the study found that consumers prefer vegetables, fruits, grain and beans, milk, meat and eggs to be organic, which are ranked according to the degree of preference. Moreover, the research suggests that the main barriers bringing about the gap between attitudes and behaviors are price, the distrust on certifications of organic food, and unavailability. These findings have implications for marketing communications to consumers and potentially for organic product development

Cuticle Protein LmACP19 Is Required for the Stability of Epidermal Cells in Wing Development and Morphogenesis of Locusta migratoria

Insect wing consists of a double layer of epidermal cells that produce and secrete the dorsal and ventral cuticular components. It is important for the stability of epidermal cells during wing development and morphogenesis, but its specific gene expression and physiological function during this process remain unclear. In our previous work, a wing cuticle protein gene LmACP19 was identified in Locusta migratoria based on transcriptomic data. Here, we report on its roles in wing development and morphogenesis. LmACP19 encodes a chitin-binding protein belonging to RR-2 subfamily of CPR family, which is highly homologous to CP19-like proteins in other insect species. RT-qPCR analysis revealed that LmACP19 is highly expressed in wing pads of fifth-instar nymphs, and its encoded protein is located in two layers of epidermal cells but not in the cuticle. Suppression of LmACP19 by RNA interference led to abnormal wing pad and wing morphogenesis with curved, unclosed, and wrinkled phenotypes during nymph-to-nymph and nymph-to-adult transition, respectively. Furthermore, deficiency of LmACP19 affected arrangement of epidermal cells, resulting in apoptosis. Our results indicate that LmACP19 is indispensable for wing development and normal morphological structure by maintaining the stability of epidermal cells during L. migratoria molting

Sea-level changes control coastal organic carbon burial in the southern East China Sea during the late MIS 3

Coastal depositional systems play a crucial role in the sequestration of terrigenous organic carbon (OC), especially deltas and coastal mud belts, which are two of the most efficient OC burial hotspots. Investigation into long-term coastal OC burial is challenging since the analysis of modern coastal environments only provides a snapshot of OC burial. Marine Isotope Stage 3 (MIS 3) refers to a unique interval in the last glacial period, characterized by a protracted falling sea level punctuated by millennial-scale climate oscillations. The study of OC burial during MIS 3 can help to estimate and predict changes in coastal OC burial driven by sea-level oscillations and extreme climate events. Here, we target late MIS 3 strata beneath the southern East China Sea. Based on the analysis of total organic carbon, total nitrogen content, stable organic carbon isotopic composition, and major and trace elements, this study demonstrates that relative sea-level changes control sediment provenance and sedimentary processes in coastal environments, which in turn regulate coastal OC burial during the late MIS 3. The burial of OC in the coastal ocean during MIS 3 deviates from the typical expectation that carbon burial is facilitated during transgression or high sea-level periods. Sediments deposited during high sea-level periods in late MIS 3 exhibit the lowest OC burial flux and contents due to long-distance transport from distant sources. The study highlights that the highest burial flux and contents of OC were found in deposits preserved during sea-level lowstands. This indicates that short-distance transport, local sources, and mountainous rivers affected by the monsoon and experience frequent floods, are associated with the highest OC burial and contents. Short and rapid climate warming events likely contribute to OC burial in late MIS 3 by intensifying precipitation and nutrient-rich supplies, thereby increasing the input of terrestrial and marine OC. This observation is noteworthy as it challenges the conventional understanding of the relationship between sea level and carbon burial. The study of OC burial in late MIS 3 is helpful in understanding how OC burial reacts to sea level oscillations and rapid climate warming events

Layer-Switching Mechanisms in Sb2Te3

Interfacial phase‐change memory (iPCM) based on layer‐structured Ge‐Sb‐Te crystals has been recently proposed, offering an energy‐efficient implementation of nonvolatile memory cells and supplementing the development of Ge‐Sb‐Te‐based phase‐change random access memories (PRAMs). Although the working principle of iPCM is still under debate, it is believed that layer‐switching plays a role in the switching process between the low‐resistance and high‐resistance states of iPCM memory cells. However, the role of Ge in forming swapped bilayers—the key elements for layer‐switching—is not yet clarified. This work manages to achieve layer‐switching in Sb2Te3 thin films by manipulating the formation of bilayer defects using magnetron sputtering and post‐thermal annealing. By combining scanning transmission electron microscopy (STEM) experiments with density functional theory (DFT) calculations, the essential role of Sb‐Te intermixing is elucidated in stabilizing swapped bilayers at a low energy cost. In situ STEM experiments provide a real‐time and real‐space view of dynamical reconfiguration of van der Waals‐like gaps in Sb2Te3 thin films under electron‐beam irradiation. The results show that the Ge atoms are not necessary for the formation and motion of swapped bilayers, providing atomic insights on the layer‐switching mechanism in layer‐structured binary and ternary group V‐ and IV–V‐tellurides for memory applications