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Tunable optical devices are of great interest as they offer adjustability to their functions. Temporal optics is an evolving new field, and utilizing it are useful as for revolutionize basic research of time-dependent phenomena as for leading toward full optical devices. With increasing focus on ecological compatibility, bio-friendly alternatives are of key subject. Water in its various forms can uniquely open up new physical phenomena and applications in photonics and modern electronics in unique ways. Water droplets freezing on cold surfaces are ubiquitous in nature. We propose and demonstrate the effectual generation of time domain self-bending photonic hook (time-PH) beams by using freezing water droplet. The PH light bend near the shadow surface of the droplet into large curvature and angles superior to a conventional Airy beam. The key properties of the time-PH (length, curvature, beam waist) can be modified flexibly by changing the positions and curvature of the water-ice interface inside the droplet. Due to the modifying internal structure of freezing water droplets in real time, we showcase the dynamical curvature and trajectory control of the time-PH beams. Compare with the traditional methods, our phase-change based materials (water and ice) of the mesoscale droplet has advantages of easy for fabrication, natural materials, compact structure and low cost. Such a PHs may have applications in many fields, including temporal optics and optical switching, microscopy, sensors, materials processing, nonlinear optics, biomedicine, and so on.

The Chinese national emergency warning system has been officially launched since 2015 to provide multi-hazard warnings to the public, but its efficiency and effectiveness remain unclear. Based on a...

Permeability is a major indicator of concrete durability, and depends primarily on the microstructure characteristics of concrete, including its porosity and pore size distribution. In this study, a variety of concrete samples were prepared to investigate their microstructure characteristics via nuclear magnetic resonance (NMR), mercury intrusion porosimetry (MIP), and X-ray computed tomography (X-CT). Furthermore, the chloride diffusion coefficient of concrete was measured to explore its correlation with the microstructure of the concrete samples. Results show that the proportion of pores with diameters 50 µm, X-CT obtains the maximal contributive porosity, followed by MIP and NMR.

Some new unusual physical phenomena and effects associated with dielectric mesoscale particles with Mie size parameter near 10 were studied and have been discovered during the last decade. In this paper, we propose nanoholes structured wavelength-scaled dielectric cubic particle with refractive index near two, where the array of nanoholes can act as a plurality of near-field probes to simultaneously illuminate the sample surface and it has the potential of surpassing the performance of most existing nearfield imaging approaches. We also offer the concept of the single nano-structuring of a dielectric cylinder or sphere made from conventional optical materials. The choice of the diameter of the nanohole in the particle "transfers" it into the resonance mode, when the characteristics of the field localized in the shadow part of the particle are determined not by the wavelength, but by the size of the nanohole. Thus, the diameter of the focused spot at the exit from the particle can be much smaller than the solid immersion diffraction limit., 6 pages

Melastomataceae have abundant morphological diversity with high economic and ornamental merit in Myrtales. The phylogenetic position of Myrtales is still contested. Here, we report the first chromosome-level genome assembly of Melastoma dodecandrum in Melastomataceae. The assembled genome size was 299.81 Mb with a contig N50 value of 3.00 Mb. Genome evolution analysis indicated that M. dodecandrum, Eucalyptus grandis and Punica granatum were clustered into a clade of Myrtales and formed a sister group with the ancestor of fabids and malvids. We found that M. dodecandrum experienced four whole-genome polyploidization events: the ancient event was shared with most eudicots, one event was shared with Myrtales, and the other two events were unique to M. dodecandrum. Moreover, we identified MADS-box genes and found that the AP1-like genes expanded, and AP3-like genes might have undergone subfunctionalization. We found that the SUAR63-like genes and AG-like genes showed different expression patterns in stamens, which may be associated with heteranthery. In addition, we found that LAZY1-like genes were involved in the negative regulation of stem branching development, which may be related to its creeping features. Our study sheds new light on the evolution of Melastomataceae and Myrtales, which provides a comprehensive genetic resource for future research.

A corrugated surface long period grating (LPG) is fabricated on a commercial multimode plastic optical fiber (POF) by a simple mechanical die press print method. This so-obtained LPG is proposed as a refractive index (RI) sensor. The LPGs imprinted on the POFs with different diameters are evaluated, and it shows that an LPG on a thin POF (with a diameter of 0.25 mm) exhibits better RI sensing performance than that of the ones on thick POFs (with diameters of 0.5 and 1.0 mm). By altering the structural parameters of the LPG on the POF with a diameter of 0.25 mm, the RI sensing performance is studied. When the grating period is $100~\mu \text{m}$ , the groove depth is $65~\mu \text{m}$ , and the tilted angle is 20°, the optimum sensitivity of 2815%/RIU with a resolution of $1.39\times 10^{\mathbf {-4}}$ RIU is achieved in the RI range of 1.33–1.45. In addition, the characteristic of the temperature dependence of the sensor is presented. The proposed sensor is a low-cost solution for RI measurement and with the features of simple structure, easy fabrication, and intensity modulation at visible wavelengths.

A series of experiments, including natural gas molecular composition, carbon isotope analysis and fluid inclusion petrography and microthermometry were conducted to research the origin and formation of natural gases in the Middle Ordovician Yijianfang Formation and the Middle-Lower Ordovician Yingshan Formation, Gucheng-Shunnan block. Natural gases consist predominantly of methanes, with dry coefficients of 0.951–0.999 and have relatively heavy carbon isotopic signatures, with average δ13C1 and δ13C2 values of −36.4‰ and −32.5‰, respectively. The diagrams between δ13C-C1 versus C1/(C2 + C3) and methane carbon isotope versus ethane-propane isotopic separation suggest that these gases are oil-associated thermogenic gas from type Ⅱ kerogen with high thermal evolution extent of the source rocks. The empirical correlation of ln(C1/C2) and ln(C2/C3) indicates natural gases originated from crude oil cracking. Natural gases in the Gucheng block and the Shunnan block have properties similar to those of oil-cracking gases in the Eastern Lungu block and the Eastern Tazhong block. Due to reservoir temperatures being lower than formation temperatures of the gases and the potential of higher mature source rock being almost exhausted, natural gases originated predominantly from the cracking of deep paleo-oil pool rather than dispersive dissoluble organic matter in the source rocks. The comprehensive analysis of thermal evolution history, burial history, fluid inclusions and geological conditions suggest that natural gases formed during Himalayan stage. Deep oil-cracking gases accumulated in the Ordovician reservoir through migration along faults. Therefore, deep-seated natural gases have great potential for exploration.

At present, deep and ultra-deep oil and gas have become the research and exploration hotspots. With little drilling data available, the geological understanding on deep formations is still in the exploratory stage, but most petroleum geologists have universally acknowledged that the deeply-buried strata of Chinese marine craton basins are equipped with the conditions for abundant oil and gas resources. A series of discoveries have been made in the Ordovician and Cambrian strata. For Precambrian strata, besides breakthroughs in the Sichuan Basin, a lot of research or drilling work has been initiated in other basins. In the Tarim Basin, the current burial depth of the Lower Paleozoic and the Precambrian mainly ranges from 5000 to 12000 m. This is attributed to rapid subsidence and deposition since the Neogene. A large number of exploration discoveries have been made, and commercial productivity projects have been constructed at the depth less than 8000 m. Strata more than 8000 m deep will be a significant major prospecting exploration field in the future. The analyses of hydrocarbon accumulation conditions of the ultra-deep layers of the Tarim Basin provide theoretical guidance for ultra-deep oil and gas exploration. This research is based on source rocks in the Cambrian, Sinian, and Nanhua System, formation and preservation of ultra-deep carbonate reservoirs, phase of petroleum and accumulation assemblages in ultra-deep strata, the exploration fields deeper than 8000 m were also evaluated to sort out the most favorable areas and, future exploration focuses on the Ordovician, Cambrian, and Sinian strata are pointed out. Keywords: Ultra-deep, Neoproterozoic, Phase of petroleum, Cambrian, Craton basin, Tarim Basin

Upconversion emission dynamics have long been believed to be determined by the activator and its interaction with neighboring sensitizers. Herein this assumption is, however, shown to be invalid for nanostructures. We demonstrate that excitation energy migration greatly affects upconversion emission dynamics. “Dopant ions’ spatial separation” nanostructures are designed as model systems and the intimate link between the random nature of energy migration and upconversion emission time behavior is unraveled by theoretical modelling and confirmed spectroscopically. Based on this new fundamental insight, we have successfully realized fine control of upconversion emission time behavior (either rise or decay process) by tuning the energy migration paths in various specifically designed nanostructures. This result is significant for applications of this type of materials in super resolution spectroscopy, high‐density data storage, anti‐counterfeiting, and biological imaging.

Cymbidium hookerianum Rchb.f. is an ornamental orchid with large flowers and delicate aroma. Here, we reported the complete chloroplast genome sequence of C. hookerianum. The total chloroplast genome cycle was 155,447 bp. It displayed a typical structure including one large single-copy (LSC, 84,186 bp) region, one small single-copy (SSC, 17,839 bp) region, and two inverted repeat (IRs, 26,711 bp). 124 genes (78 CDSs, 38 tRNAs, 8 rRNAs) were encoded by the cp genome. The average GC content of this sequence was 36.8%. The phylogenetic analysis revealed C. hookerianum and C. changningense are sisters. The groundwork of chloroplast genome would provide available reference for molecular taxonomy and breeding.

The current study sought to offer guidance for developing effective web-based mapping tools for wildfire warnings by identifying (1) the important content for facilitating individuals’ decision-making, and (2) the optimal interface design for ensuring usability and ease of information access. A map-based warning tool was prototyped in the Australian context, followed by a usability and effectiveness evaluation through individual interviews and verbal protocol analysis to assess participants’ interaction with the mapping interface and information in response to the simulated warning scenario. The results demonstrated variations in participants’ approaches to wildfire warning response, revealing varied information needs. Specifically, most participants relied on their own assessment of the prospective threat, requiring specific wildfire-related information before eliciting a response. In contrast, the decision of a minority of the participants was motivated by response guidance from agencies, and accurate wildfire information was less important for their response. Imperative information for both types of residents therefore needs to be highlighted in a map-based warning tool to cater to a wide audience. Furthermore, a number of heuristics were identified for designing effective interactive functions to facilitate the control of, and access to, the various maps and textual information presented on the map-based warning interface.

Official warnings are essential for informing the public of impending hazards and promoting their responses before a disaster occurs. However, research has identified that traditional public warnings, such as generic text messages based on large geographic regions, often fail to promote appropriate responses by at-risk residents. Recently, there has been an increased focus on using map-based approaches for communicating public warnings. However, a systematic framework to guide the design of effective mapping instruments for this purpose is lacking. The researchers sought to fill this gap by merging the scholarly understanding of factors influencing warning effectiveness with the contemporary spatial capacities of the emergency management sector. The current paper presents the conceptual framework resulting from this merger, which can be used to direct the design and implementation of map-based warnings that offer personalised risk visualisation and provide personalised decision support to motivate...

ABSTACT Phalaenopsis mannii, one of the native Phalaenopsis in China, is an important parent for breeding new varieties. However, its position has been unclear in Phalaenopsis. The obtained high-quality P. mannii chloroplast genome will provide useful information for phylogenetic and future breeding of Phalaenopsis. Herein, we reported a complete chloroplast genome of P. mannii from Yunnan, China. The sequencing data obtained from BGISEQ-500 platform were assembled. This sequence had a circular molecular length of 148,596 bp and contained a total of 127 genes with an average GC content of 36.7%. Phylogenetic analysis indicated that Phalaenopsis was monophyletic with strong support, in which the P.mannii was the sister-group of Phalaenopsis aphrodite subsp. formosas, Phalaenopsis ‘TinyStar’ and Phalaenopsis equestris.

An important horticultural moth orchid in China, Phalaenopsis lobbii, has small and lovely flowers with unique labial characteristics. We sequenced the chloroplast genome (cpDNAs) of P. lobbii and ...

Cymbidium maguanense is a valuable orchid endemic to China, with delicate smelling, ivory white flower, and showy yellow labellum. Herein, we reported the complete chloroplast genome of C. maguanen...

Here, we propose the concept of an “optical vacuum cleaner” for optomechanical manipulation of nanoparticles. We utilize a dielectric cuboid to generate an optical gradient force exerted on the nanoparticles for particle’s hovering and trapping. We show that the permittivity contrast between the particle and the nanohole leads to the deep subwavelength light confinement and enhancement at the opening of the nanohole located at the shadow surface of the particle. The proposed “optical vacuum cleaner” can be utilized in optomechanical manipulations on particles such as noble metal nanoparticles adsorbed on surfaces or controlling the particles taking part in cellular uptake.

Objectives: To investigate the effectiveness of contralaterally controlled functional electrical stimulation (CCFES) on the recovery of active wrist dorsiflexion and upper limb function in patients with early-phase stroke (

The comprehensive land carrying capacities of seven cities in the Shandong Peninsula Blue Economic Zone between 2007&ndash, 2014 were assessed using a multi-criterion comprehensive evaluation approach and an index of 27 indicators, and cluster analysis was conducted to identify the spatial-temporal variations of the cities&rsquo, comprehensive land carrying capacities. The results showed that the carrying capacity of the water and soil resources of the cities had declined except Dongying City, in contrast, the carrying capacities of the eco-environment, the social resources and the economy and technology of the seven cities had all arisen. The carrying capacities of social resources of Dongying and Weihai were markedly higher than the other five cities. The carrying capacities of economy and technology of Qingdao and Dongying were high, the capacities of Weihai and Yantai were moderate, and the capacities of Weifang, Rizhao, and Binzhou were low. In general, the comprehensive land carrying capacities of the eastern cities were higher than those of the western cities, which was similar to the spatial pattern of the economy development of those cities. In addition, positive correlations were identified between the comprehensive land carrying capacity and the per capita land for construction, areal proportion of wetland to total land, percentage of green space to build up area, per capita public green space, comprehensive utilization rate of industrial solid waste residues, urbanization rate, area of per capita urban road, per capita GDP, economy density, fixed-assets investment per area, etc. However negative correlations were discovered between the comprehensive land carrying capacity and the discharge of industrial waste water per 10,000 Yuan RMB GDP, as well as the proportion of added value of the primary industry to total GDP. Finally, we discussed measures to improve the comprehensive land carrying capacities of the cities, such as elevating the intensive land utilization and economic development, decreasing the proportion of added value of the primary industry to total GDP, promoting energy saving and emission reduction, etc.

Maps are a sensible approach for communicating wildfire early warnings to the public as such warnings often contain a multitude of spatial information. However, a reluctance of agencies was found in using accurate and timely wildfire maps for public warnings, a sentiment potentially fuelled by beliefs that the public are not fluent map-readers and may be overwhelmed by the large amount of information. To test the validity of these beliefs, this study empirically compared the effectiveness of maps versus traditional text-based approaches for communicating spatial-related wildfire warning information. Through an online survey, 261 residents from wildfire prone areas in Western Australia were asked to view multidimensional spatial information regarding a simulated wildfire scenario presented as either text messages or maps, and were subsequently queried for their comprehension, their risk perceptions, and the attractiveness of the presentation format. Additionally, the survey captured the time required to interpret the varied information representations. The results showed that appropriately designed maps prevailed over text messages for the communication of most wildfire warning information by improving comprehension, elevating risk perceptions, and increasing appeal to the public. However, an optimal communication approach would be to couple map designs with several imperative textual descriptors. Especially, the textual description of safe shelters in the community (i.e. location names and addresses) yielded indispensible meaning when the locations were well-known landmarks, and hence should not be replaced by map-based depiction. Furthermore, several heuristics were identified to facilitate the design of effective warning maps across hazards in general.

Six concrete core samples in the sluice gate exposed to a strong tidal environment have been drilled. Firstly, the chloride concentration with 1 mm interval was measured and the bidirectional chloride diffusion coefficient was fitted by Fick's second law. Besides, based on the probabilistic method, the randomness of each parameter which influences the time to corrosion initiation of reinforcement (including depth of concrete cover, peak values of chloride concentration, convection depth, chloride diffusion coefficient and critical chloride concentration) has been determined. And then, the Monte Carlo simulation method was used to analyze the probability of the time to corrosion initiation. Finally, sensitivity analysis was adopted to identify the main influence factor of service life prediction. Results indicated that the chloride diffusivity at positive side of gate is stronger than that at back surface. The time to corrosion initiation of reinforcement follows a normal distribution and the predicted mean value is consistent well with the actual measured value, confirming that in the strong tidal environment, the critical chloride content of 0.16%–0.18% by weight of concrete can be substituted into the service life prediction model. Besides, the depth of concrete cover is identified as the uppermost parameter which influences the time to corrosion initiation, followed by critical chloride concentration, peak value of chloride concentration and convection depth.

Electromagnetic interactions in the microelectronvolt (μeV) or microwave region have numerous important applications in both civil and military fields, such as electronic communications, signal protection, and antireflective coatings on airplanes against microwave detection. Traditionally, nonmagnetic wide-bandgap metal oxide semiconductors lack these μeV electronic transitions and applications. Here, we demonstrate that these metal oxides can be fabricated as good microwave absorbers using a 2D electron gas plasma resonance at the disorder/order interface generated by a hydrogenation process. Using ZnO and TiO2 nanoparticles as examples, we show that large absorption with reflection loss values as large as -49.0 dB (99.99999%) is obtained in the microwave region. The frequency of absorption can be tuned with the particle size and hydrogenation condition. These results may pave the way for new applications for wide bandgap semiconductors, especially in the μeV regime.

Qualitative activity space data, i.e. qualitative data associated with the routine locations and activities of individuals, are recognized as increasingly useful by researchers in the social and health sciences for investigating the influence of environment on human behavior. However, there has been little research on techniques for exploring qualitative activity space data. This research illustrates the theoretical principles of combining qualitative and quantitative data and methodologies within the context of geographic information systems GIS, using visualization as the means of inquiry. Through the use of a prototype implementation of a visualization system for qualitative activity space data and its application in a case study of urban youth we show how these theoretical methodological principles are realized in applied research. The visualization system uses a variety of visual variables to simultaneously depict multiple qualitative and quantitative attributes of individuals' activity spaces. The visualization is applied to explore the activity spaces of a sample of urban youth participating in a study on the geographic and social contexts of adolescent substance use. Examples demonstrate how the visualization can be used to explore individual activity spaces to generate hypotheses, investigate statistical outliers, and explore activity space patterns among subject subgroups.

This study begins to offer a tangible definition and operationalization of the required level of preparedness for safely staying and defending a property by householders in Australian wildfires. A consultative workshop was conducted with a taskforce of national experts from Australia seeking to obtain consensus on the critical nature of a wide-ranging list of preparatory actions. An innovative methodology was employed to account for the potential relationship between the desired levels of preparedness and Fire Danger Ratings (FDRs), the indicator of fire weather intensity, as was long suggested by Australian fire agencies. The resultant model includes a checklist of critical preparatory actions for each FDR that portrays a minimum and essential preparatory condition to guide an individual’s decision to stay and defend under the given fire condition. While the definition presented here does not provide a unique solution to ensure the safety of active defense under all household scenarios, it delive...

Superstructure fiber Bragg gratings constructed following the Fibonacci sequence are proposed and simulated by using the transfer matrix method. The reflection spectrum has a multi-fractal structure as a function of the wavelength and is symmetric to the center. The reflectivity has self-similarity and scaling with respect to the Fibonacci sequence order at the central wavelength. For the transmission spectrum, the interaction of the core-cladding mode is investigated and the particular wavelengths for which the resonance condition is satisfied are located by varying the grating parameters. The potential application of the quasi-periodic structure as fiber sensors is also proposed.

The numerical simulation of light wave transmission and reflection in fiber grating is presented. The simulation is based on three-dimensional finite difference time domain algorithm. A method that can make the faint reflected wave distinct and legible is also proposed. With this method, we exhibit light wave reflection and radiation in fiber grating and tilted fiber grating, respectively, in numerical simulation.

Copper–alkali ion exchange technology was used to prepare BK7 glass planar waveguides. The photoluminescence spectra of the waveguides were studied with fluorescence spectrophotometer. It was observed that there were strong emission peaks at around 520 nm, which were strongly influenced by the ion-exchange times. Besides the time, the ion-exchange temperature was important factor as well, the higher ion-exchange temperature was found to bring a blue shift of emission spectra. The blue–green emission band originates from different transition mechanism of energy level. The spectroscopy features of copper within the glass host were also affected by the excitation wavelength, which resulted in a shift of the emission band peaks.

The sound source localization method that based on triangular array of wireless sensor networks (WSN) is proposed to locate the sound source and research the error distribution. Using the Time Difference of Arrival (TDOA) algorithm, the proposed sound source localization method can be used to locate the source of impulse of sound inside or around the WSN array. The simulation experiment had positioning error distribution. Simulation results show that, the effective localization region of the proposed method is mainly located inside the WSN array and extents outward across the edges of the array. The effective localization region became bigger with the WSN array scale became lager .The simulation results also show that influence of the error of WSN node position to the localization error is greater than the errors of sound arrival delay calculation. The influence of sound arrival time difference analysis error and node location error for the effect of sound source localization increased with the increase of the WSN array scale. Keywords-wireless sensor network(WSN); sound source localization; time difference of arrival (TDOA); simulation; Error analysis