Search

A novel high-power AlGaN/GaN heterojunction lateral photoconductive semiconductor switch (PCSS) based on the SiC substrate is proposed, which achieves high dark-state resistance characteristics by groove etching. Under the action of biased electric field and incident laser, a high concentration of two-dimensional electron gas is formed at the heterojunction interface. The photo-generated free carriers transport along the heterojunction interface, which improves the utilization efficiency of photo-generated carriers. Moreover, the simulation of the current density distribution of the PCSS provides theoretical support for this phenomenon. Compared with the conventional GaN PCSS, the power capacity and conduction characteristics are further improved. The test results show that the output current of the device increases significantly after the introduction of the AlGaN/GaN heterojunction. At the biased voltage of ∼34 kV, the maximum output current of the AlGaN/GaN PCSS reaches 205 A. [ABSTRACT FROM AUTHOR]

In this work, a low-profile optical transparent wideband metamaterial absorber based on radiation–absorption reciprocal theory is proposed. The top layer and bottom layer are composed of indium tin oxide–polyethylene terephthalate films, and the middle layer is a transparent substrate polymethyl methacrylate. The method of transparent wideband absorption using reciprocal theory is proposed to guide the design. Based on characteristic mode analysis and calculated equivalent aperture efficiency, the absorber consisting of composite resonators is analyzed and designed. The equivalent circuit model and surface current distributions are studied to verify the design. The numerical results show that high absorption of greater than 90% in the frequency range of 5.7–16.4 GHz is obtained. A wideband absorption rate of greater than 80% at a 60° incident angle under TM polarization and an absorption rate of greater than 65% at a 60° incident angle under TE polarization are obtained. The proposed design has the advantages of broadband absorption, polarization insensitivity, light transmittance of more than 70%, and compact structure, which can be applied to special scenes that require optical transparency, such as anechoic chamber glass and cockpit glass. [ABSTRACT FROM AUTHOR]

In this paper, we designed double V-shaped Al/Ni multilayer energy-containing microdevices with different V-angles, and we performed finite element modeling and simulation of the heat transfer process of the designed energy-containing microdevice. Temperature-dependent resistivity was introduced to effectively simulate the phase change during ignition. We simulated the temperature and current density distribution in the central region of the Al/Ni multilayer energy-containing microdevice and predicted the ignition voltage threshold for the specific device structure. Al/Ni multilayer energy-containing microdevices with different V-angles were prepared by electron beam evaporation technology, and ignition experiments on the prepared devices under the excitation of 47 μF capacitance were conducted. The experimental results show that the critical voltage of ignition increases with the increase in the V-angle, which verifies the correctness of the proposed finite element model. [ABSTRACT FROM AUTHOR]

Scientific research has shown that the geometric structure of the metasurface has a significant impact on its ability to control the propagation of electromagnetic waves. The control of surface current can be achieved by designing the shape of the metasurface unit cell. In this paper, the traditional metasurface is studied using characteristic mode analysis, and a modified metasurface is proposed, which consists of 4 × 4 hexagonal rings with an asymmetric concave interior. The modified metasurface controls the distribution of surface current by increasing the path of surface current, thus lowering the frequency of modal significance. In addition, due to the special asymmetric concave interior, the frequency difference of different modal currents increases, leading to the expansion of the operating bandwidth of modal currents. A metasurface antenna is fabricated and measured for proof of concept. With a size of 0.69λL × 0.69λL × 0.06λL (λL is the wavelength in free space at the lowest operating frequency), the designed antenna achieves a −10 dB impedance band of 40%, 3 dB axial ratio band of 19.4%, and boresight gain of 8 dBi. [ABSTRACT FROM AUTHOR]

Alternating current (ac) losses in conductor-on-rounded-core (CORC) cables of YBCO high-temperature superconducting (HTS) tapes are a significant challenge in HTS power applications. This study employs two finite element analysis (FEA) models to investigate the contributions from different ac loss components and provide approaches for reducing ac losses in cables. An FEA model based on the T-A formulation treats the cross section of thin superconducting layers as 1D lines and, therefore, only can predict the ac loss generated by the perpendicular magnetic field. In contrast, the model based on H-formulation can be performed on the actual 2D rectangular cross section HTS tapes to provide the total ac losses generated by magnetic fluxes penetrating from both the edges and surfaces of HTS tapes, although this model requires more computing time and memory. The 1D and 2D simulation models were validated by cross comparing the results from both models and by comparing sub-section and full cross section models. Subsequently, two models relate cable design and operational parameters to the surface and edge losses of a two-layer CORC cable by considering the (1) relative contributions of edge and surface losses to the overall ac losses; (2) effect of the current distribution between inner and outer HTS layers on ac losses; (3) impact of the tape alignment on ac losses in each HTS layer; (4) influence of the thickness of HTS layers on ac losses; (5) effect of size and number of inter-tape gaps on ac losses; and (6) contribution frequency on the ac losses. The research results given in this paper are therefore not only valuable to suggest strategies for reducing ac loss in multi-layer cables but also for developing more accurate and effective methods to calculate ac loss in CORC HTS cables. [ABSTRACT FROM AUTHOR]

An innovative electromagnetic energy harvester was developed using a compact four-ring single-resistor unit cell. To achieve efficient conversion of electromagnetic waves into electricity, we integrated the high-performance Bi2Te3 thermoelectric material onto the load resistor. Remarkably, this unit cell exhibits exceptional energy harvesting capabilities at a frequency of 5.8 GHz while maintaining polarization insensitivity. Through comprehensive analysis, we evaluated the energy harvesting efficiencies, power loss distribution, and current density distribution. Additionally, we investigated the impact of incident power on the unit cell's temperature and energy conversion efficiencies. To enhance energy concentration on the load, we ingeniously designed an "L-shaped" metal through-hole structure within the four-ring single-resistor unit cell. Our results demonstrate that the four-ring single-resistor unit cell achieves an impressive harvesting efficiency of 94.5% at 5.8 GHz, with a thermal conversion efficiency of 43.3 °C/W, an electrical conversion efficiency of 0.23 mV/°C, and an electrical response rate of 9.4 mV/W. Notably, when subjected to a power input of 7 W, the unit cell produces an output voltage of 65.9 mV, and its theoretical maximum output power reaches 180 mW. [ABSTRACT FROM AUTHOR]

Summary: In today's intricate wireless communication environment, ensuring system quality demands the use of a reliable and versatile antenna system. This research article introduces a polarization reconfigurable antenna integrated with a 4 × 4 Artificial Magnetic Conductor (AMC) surface. The AMC unit cell exhibits a triple‐band reflection phase response at 1.8GHz, 4.5GHz, and 5.5GHz, demonstrating double negative metamaterial behavior. The antenna features two distinct C‐shaped metal strips connected to two PIN diodes, enabling dynamic current distribution adjustment. Consequently, the proposed antenna offers three reconfigurable states, facilitating seamless switching between dual circular polarization (left and right‐hand circular polarization) and linear polarization. With a frequency coverage ranging from 1.29 to 2.52GHz and 3.59 to 6.15GHz, the antenna boasts a maximum axial ratio (AR) bandwidth of 31.96%. Additionally, it achieves a maximum peak gain of 5.5 dB and maintains front‐to‐back ratio (FBR) values exceeding 25 dB, while recording a minimum specific absorption rate (SAR) value of 0.1059 W/kg. The integration of the AMC surface ensures enhanced performance of the antenna. Experimental results from constructed prototypes closely align with simulation outcomes, validating the effectiveness of the proposed antenna. Consequently, this antenna holds significant promise for next‐generation wireless applications. [ABSTRACT FROM AUTHOR]

In this paper, an electro-hydraulic exciter controlled by an alternating current distribution valve is proposed, and a systematic analysis of the influence of pipe effect on the vibration characteristics of the electro-hydraulic exciter is investigated by simulation and experiments. The vibration characteristics curves for different pipe parameters are obtained, and the relative errors between simulation and experiment are evaluated. Moreover, a significant regression model of pipe parameters and vibration characteristics of the electro-hydraulic exciter is established by using the quadratic regression analysis method and the Box-Behnken experiment design method. Significant differences in the influence of pipe parameters on vibration characteristics are obtained by ANOVA (Analysis of Variance), and the influence of pipe parameter interaction on vibration characteristics is discussed. The results show that the relative importance of pipe parameters on the vibration characteristics of electro-hydraulic exciter, from high to low, is as follows: pipe diameter, elastic modulus, and pipe length. Notably, there is also an interaction between the pipe parameters, and the significance of these interactions is ranked from high to low as the interaction between the layers of steel wire and diameter, the interaction between diameter and length, and the interaction between the layers of steel wire and length. [ABSTRACT FROM AUTHOR]

A dc voltage restorer (dc‐VR) with optimal droop control is developed to reduce the power loss and solve the dynamic current imbalance simultaneously of the zonal dc distribution system integrating multi‐parallel energy storage. Firstly, the power loss model composed of line loss and converter loss is built and it is proved to be a strictly convex function with respect to droop coefficients, which indicates the power loss can be mitigated by optimizing the current distribution. Thus, an image‐based droop optimization method is proposed to search for the optimal droop coefficients. Then, the economy of voltage compensation on power loss reduction is investigated and an ESS‐combined dc‐VR is designed, including an interleaved parallel architecture and a capacitor‐integrated electric spring (C‐ES). Unified virtual inertia is proposed for interleaved parallel bridge arms to make their dynamic performance consistent. And the newly introduced C‐ES can keep the bus voltage at the rated level to reduce the system cost. Therefore, the problem of dynamic currents imbalance is addressed from the points of converter structure (dc‐VR) and control system (unified inertia), and the power loss can be reduced by voltage recovery (C‐ES) and optimizing the current reallocation which is achieved by updating sharing coefficients from the image‐based droop optimization method. Finally, the simulation cases validate the effectiveness of the proposed optimal‐droop dc‐VR on dynamic current balance and power loss reduction, and hardware in the loop experiment results prove the consistent dynamic characteristics of the dc‐VR's arms. [ABSTRACT FROM AUTHOR]

The Reeves' muntjac Muntiacus reevesi is an ungulate native to China and Taiwan that has been released into the wild in several continental European countries and the United Kingdom. We present recent records of the species in mainland France. We also investigated the dispersal rate and density of the established population in the Centre-Val de Loire region. The number of observations of M. reevesi was low in the period 2008–2016, increased sharply until 2019 and then decreased until 2023. From a comparison between the distribution in 2008–2012 and 2013–2017, the dispersal rate was estimated at an average of 3.2 km/year, and 7.6 km/year between 2013–2017 and 2018–2023. Based on a camera trap protocol, the population density was assumed to be very low in forested areas but estimated with a lack of robustness due to a single observation. Further efforts must be made to better assess the risk of an increase in the wild population of Reeves' muntjac in the Centre-Val de Loire region. To prevent potential impacts, rapid control measures can be put in place in the large area (10,800 km2) where muntjacs are now rapidly spreading. [ABSTRACT FROM AUTHOR]

Transparent heaters are gaining significant attention for applications such as antifog glass, smart windows, and smart farm greenhouses. A transparent heater basically consists of transparent conducting materials that serve as a heating area and contact pad electrode to apply power. To fabricate a transparent heater, materials with excellent light transmittance and low sheet resistance are required. Among various transparent conducting materials, such as Indium Tin Oxide (ITO), carbon nanotube (CNT), graphene, and silver nanowires (AgNWs), AgNWs are particularly favored due to their good electrical, optical, and mechanical properties. However, in order to improve the heating characteristics of transparent heaters, research is essential not only on improving the properties of transparent conducting materials but also on the design of contact pad electrodes that can uniformly improve current distribution. Here, we explore various shapes of contact pad electrodes for AgNW-based transparent heaters to improve current distribution. Shapes such as line, spot, twisted, and parallel-type contact pad electrodes are designed and investigated to optimize overall heating characteristics. We analyze the heating properties of these transparent heaters with various contact pad electrodes, demonstrating how their specific shape and size affect heating characteristics and uniformity. We also investigate the optimal shape of the contact pad electrode to minimize transmission loss through UV-VIS spectroscopy. As a result, we confirm that the shape of the contact pad electrode was important for simultaneously achieving high heating characteristics of 120 °C, good heating uniformity, and over 80% transparency in an AgNW-based transparent heater. [ABSTRACT FROM AUTHOR]

By 1985, approximately 400,000 ha of the keystone species Shinnery oak's (Quercus havardii) historic distribution had been eliminated for agricultural purposes across the southwestern United States. These trends indicate a need for targeted conservation and restoration efforts, especially considering the increased attention received for its role in providing habitat for endangered fauna. Setting spatially explicit conservation targets can be challenging for species with limited distributions, as the change in climate conditions over time may disconnect the relationship between environmental suitability and static, topo‐edaphic factors. Our objective was to identify areas for Shinnery oak restoration and conservation and explore the role climate plays in determining these areas while considering topo‐edaphic relationships. We constructed ecological niche models to estimate Shinnery oak's distribution under current climate conditions and temporally transferred our model using an ensemble‐mean of general circulation models to identify areas predicted to retain environmental suitability for Shinnery oak through 2100. The current distribution model was best informed by one climate and two topo‐edaphic variables. We created a second distribution model excluding topo‐edaphic variables to estimate future plant–climate relationships. Incorporating insights from models informed by both static (e.g. soil) and dynamic (e.g. climate) variables, we identified areas for conservation characterized by persistent climate suitability and high soil type suitability. Lastly, we incorporated data on land use and ownership to explore socio‐ecological influences on management decisions. By identifying areas of agreement between our modeled distributions and considering social context, we prioritized conservation areas where environmental suitability persists under changing conditions to facilitate restoration success. [ABSTRACT FROM AUTHOR]

Platycodon grandiflorus has long been used for its medicinal, culinary and ornamental properties. With increasing market demand and the depletion of wild resources, understanding the distribution and factors affecting its habitat suitability is crucial for its conservation and sustainable utilization. This study aims to predict the suitable habitat for P. grandiflorus in China considering current and future climate scenarios. The MaxEnt model, with an AUC value of 0.846, demonstrated good predictive ability for the current and future distribution of P. grandiflorus. It also identified the central, eastern, and southern regions as suitable habitats, with the critical environmental factors being precipitation, temperature, and elevation. Future scenarios under both SSP126 and SSP585 projections indicate an increase in suitable habitats, particularly in northeastern and central China, albeit with a shift in the distribution center towards the northeast by 2041–2060 and 2081–2100 under different scenarios. P. grandiflorus' distribution is significantly influenced by environmental factors, with precipitation and temperature being pivotal. Taken together, our study predicts an expansion of suitable habitats under future climate scenarios and the northward shift in the distribution center underlines the impact of global warming on the distribution of P. grandiflorus. The findings are crucial for the conservation, effective utilization, and strategic planning for the cultivation of P. grandiflorus in the face of climate change. [ABSTRACT FROM AUTHOR]

A novel compact rectangular fractal-shaped antenna for tri-band wireless communication applications is developed in this article. The proposed fractal shaped is achieved by cutting two rectangular slots in the rectangular monopole. Additionally, a stub is introduced in the bottom side of the antenna to enhance the impedance bandwidth of the acquired three bands. The developed antenna has a compact size 22 × 34 × 1.6 mm3. The CST MWS is used to design the antenna and its characteristics including S11, current distribution, radiation characteristics are exposed and analysed. To demonstrate that the simulation outcomes are reliable, the suggested antenna is manufactured and put through testing on an E5071C VNA. Additionally, the results of the experiments demonstrate that the designed antenna offers three impedance bandwidths 2.25–2.96 GHz, 3.56–4.01 GHz, and 4.6–5.86 GHz, which shields all the LTE, WLAN, WiMAX, and C-band applications. The proposed tri-band fractal antenna also provides good gain at the operating frequencies and an omnidirectional radiation pattern. [ABSTRACT FROM AUTHOR]

A low-noise amplifier (LNA) is one of the most crucial components of a communication system. The current low-noise amplifier design faces challenges due to intrinsic noise sources in CMOS transistors and trade-offs to maximize gain and bandwidth. Hence the Optimal design of a low-power ultra-wideband low-noise transconductance amplifier in 0.18 µm CMOS is introduced to minimize the noise figure of the amplifier. Ultra wideband (UWB) signals cover a wide frequency range making it challenging to achieve good input and output matching across the entire band. Thus, Cascode inductive degenerative using pi matching network enhances input–output matching by providing impedance transformation, matching source impedance to low input impedance, and improving power transfer rate. However, the cascode configuration with pi matching offers superior performance over a wide frequency range, but it requires careful consideration of gain and noise figures. Therefore, a current reuse technique is utilized to improve gain and reduce noise figures by optimizing the distribution of bias currents and enhancing the overall performance of the amplifier. Furthermore, the main design challenge for LNAs is achieving high linearity in interference-filled environments. Hence novel Cascade inductive degenerative using T matching network addresses low-frequency signal interference by utilizing multiple amplifier stages for gain and high linearity. Thus, the result obtained showed that the proposed model outperforms the existing design with high gain of 17.7 dB, high input return loss of 10.6 dB, high FOM of 24.4 and low noise figures of 0.573 dB, thus improves the overall performance of the system. [ABSTRACT FROM AUTHOR]

The North Pacific distribution of coastal aleocharines has been explained as the result of either dispersal or vicariance. The rove beetle genus Psammostiba is a marine littoral group that occurs on the Pacific coasts of the Northern Hemisphere. We performed phylogenetic analysis of Psammostiba using molecular characters (4685 bp) to investigate their biogeographic patterns. The data were analysed using parsimony, Bayesian and maximum likelihood methods. Model‐based analyses showed the same pattern of Psammostiba species relationships, but parsimony analysis yielded different species relationships for the unresolved clade of Psammostiba. According to the reconstruction of the ancestral areas, both vicariance (two events) and dispersal (one event) have played roles in shaping its current distribution. Biogeographical analyses suggest that the common ancestor of Psammostiba occurred widely along the Pacific coasts of the Northern Hemisphere and underwent vicariance events. [ABSTRACT FROM AUTHOR]

Common terminal voltage measurement can be hardly applied to detect quenches in long high temperature superconducting (HTS) conductor on round core (CORC) cable because not only the HTS normal zone propagation velocity (NZPV) is low but also immobilizing a large number of voltage leads is inconvenient. Distributed optical fiber sensing (DOFS) technology is a promising method for quench detection of long superconductors. To sense the thermal changes of CORC cables during quenches more directly and prevent optical fibers from damages by external stress, a fiber-superconducting composite (FSC) CORC cable was fabricated. For this cable, three optical fibers were placed in three grooves of the copper core respectively, then three HTS tapes were spirally wound on the copper core in sequence. Comparing to a traditional CORC cable, obviously, the FSC CORC cable structure has been changed. To promote FSC CORC cable engineering applications, it is necessary to study the fundamental performance of the cable. In this paper, we investigated the electromagnetic, thermal and mechanical properties of the FSC CORC cable by comparing those with a common one. The results demonstrated that, compared to the common one, the magnetic distribution of the FSC CORC cable hardly changed, but the current distribution of the copper core in the FSC CORC cable slightly changed which led to decreases of transport AC loss, in addition, the thermal characteristics of the FSC CORC cable was slightly changed and the bending tolerance ability of the cables reduced within a bending diameter range of 15 cm. What's more, the embedded optical fibers combined with DOFS system are successfully used to detect the temperature changes of the cable surface. Finally, to study the quench behaviors of the cable, we built a quench detection platform, which equips with a voltage acquisition system, a thermocouple temperature acquisition system and the DOFS system. By using the platform to detect the quenches of the FSC CORC cable, minimum quench energy of the cable and NZPV of the tape and cable at different currents was tested. [ABSTRACT FROM AUTHOR]

This paper is a 'follow-on' from a paper previously published in this journal dealing with the laboratory to pilot scaling up approach using Industry 4.0 manufacturing methods. In particular, the paper reports a strategy for developing a model for the electroforming of nickel from a sulphamate electrolyte at laboratory scale which could subsequently provide an educated approach for transferring the process to a larger scale. At the laboratory scale, a rotating disc electrode assembly was used, which is a standard instrument to determine electrochemical parameters. Thereafter, small scale nickel discs were electroplated using this equipment, and a model of this process was developed and validated against those experimental results. These parameters were then used to actually produce electroforms in a prototype, 18 L tank system. Cross-validation between practical experiments and simulations followed which allowed for fine-tuning the model until it was consistently predicting the real process results within an acceptable error. Overall, it was found that a secondary current distribution model could be used for reasonably accurate description for the electroforming process, and could provide a quick virtual tool at a production facility. [ABSTRACT FROM AUTHOR]

The current distribution network is developing toward the direction of information and intelligent distribution Internet of Things (IoT). In order to explore the online monitoring system for transient electromechanical simulation of distribution networks, this paper is based on the equivalent model of generator sets. Firstly, it describes the relevant theoretical knowledge of edge computing, designs the distribution IoT based on edge computing, and briefly introduces its network architecture. Secondly, based on the discrete-time domain equivalent model of generators, the electromechanical transient simulation distribution network is constructed by introducing the machine network division of the power network. Finally, the Western System Coordinating Council (WSCC)-3 units and 9 nodes are taken as an example, and simulation experiments are conducted under two fault simulation conditions to verify the effectiveness of the simulation model. The results show that under the two fault simulation conditions, the results of equivalent model simulation of generator terminal voltage and relative power angle change are like those of the Power System Analysis Software Package (PSASP). The changing trend of the two is similar and stable. After the PSASP results are stabilized at a value, the simulation results fluctuate extremely up and down the value. For example, under fault condition 1, the changing trend of the relative power angle of the No. 2 generator is first fluctuating and then becomes stable. After violent fluctuation, the relative power angle tends to be stable from about 20s to -12.35°. The result of PSASP software is stable at -12.35°. The transient electromechanical simulation of the generator equivalent model can provide some ideas for the online monitoring system of the distribution network. [ABSTRACT FROM AUTHOR]

The application of inverse design in engineering is constrained by uncertainty over when to cease calculations owing to solution fluctuations and suboptimal aerodynamic parameter distribution. The proposed method for inverse design optimization incorporates active subspace assistance to effectively address these significant limitations. The optimal load distribution is achieved by the integration of sparse polynomial approximation and genetic algorithm. Furthermore, active subspace method is employed to solve the control zone of optimal static pressure/load distribution. The inverse design calculation is terminated when current load distribution falls completely within the control zone. Within the control zone, all static pressure/load distributions following a certain variance are guaranteed to provide nearly identical aerodynamic performance. The results indicate that the static pressure/load distribution of the final solution entirely falls within the control zone, while its aerodynamic performance approximates the optimal target value. In comparison to the initial solution, the final solution exhibits a significant decrease of 3.6% in the total pressure loss coefficient. [ABSTRACT FROM AUTHOR]

An anode‐support microtubular solid oxide fuel cell (MTSOFC) using an intermediate ring‐shaped electrode collector is simulated using COMSOL Multiphysics software to investigate current density distribution and mass transfer in both power generation and electrolysis modes. The cell is converted to power generation mode during continuous electrolysis, and the electrochemical performance of MTSOFC is tested to study the effect of electrolysis on the power generation performance. The power density output of the MTSOFC decreases from 250 to 150 mW cm−2 after only 40 h of continuous electrolysis. The microstructural changes in different regions during operation are observed through posttest analysis conducted on the fuel inlet, electrochemical reaction concentration region, and fuel outlet of the microtubular cell. The local agglomeration of nickel occurs in the concentrated region of the electrochemical reaction, while the coarsening of nickel oxidation mainly takes place at the fuel inlet and outlet. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxon Methods Results Main Conclusions The aim of this study is to infer the geographic dispersal paths and the environmental conditions that shaped the historical biogeography of Brachistosternus scorpions in South America. We evaluated the role that altitude and aridity had on the geographic distance that each species dispersed from the location of the genus common ancestor. Based on the previous studies, we evaluated the hypothesis postulating that species geographic expansion was promoted by arid conditions in high altitudes.South America.Brachistosternus genus.We integrated two methodological approaches in this study, the phylogenetic Geographical model and the Conductance model, considering the uncertainty associated with the phylogenetic relationship and the species classification. The Geo model infers the locations of ancestral species in a phylogenetic tree, assuming a spherical space and using samples of georeferenced locations for every species as input data. It allows us to estimate the species dispersal routes and distances from the location of the genus common ancestor. The Conductance model is based on the circuit theory and infers the geographic route and distance of least resistance between an origin and destination point. We defined the origin as the location of the genus common ancestor obtained from the Geo model and a destination point as the current geographic location of each species. This model infers the geographic routes with the least cost of resistance for dispersal in a landscape of varying altitude and aridity. Finally, we evaluated the correlation between the two dispersal distances each species have moved from the location of the common ancestor, that is, the distance inferred from the Geo model and from the Conductance model.The Geo model shows that Brachistosternus's geographical origin was most likely along the coast of south Peru, and central Chile. From this location, extant species dispersed thorough routes ranging from 873 to 2800 km in average. The Conductance model that considers the routes with least resistance to elevation and aridity simulated dispersal distances that are highly correlated with the species dispersal distances obtained from the Geo model.We revealed the geographic dispersal routes, with the least resistance to the pressures imposed by changes in altitude and aridity, that 55 species of scorpions have probably followed in the last 30 million years in South America. These geographic routes that went along the Andean Mountains and the arid zones of South America shaped the current spatial distribution of the genus Brachistosternus. [ABSTRACT FROM AUTHOR]

This paper focuses on designing a band stop filter based on epsilon-negative frequency-selective surface (FSS). The unit cell has an electrical length of 0.104λ0 × 0.104λ0 which offers a bandwidth of 2.53 GHz from 1.24 GHz to 3.77 GHz. It has a center frequency of 2.44 GHz and the obtained fractional bandwidth is above 100%. Additionally, the behavior of the presented FSS is explained by the equivalent circuit model and surface current distribution. Within the entire bandwidth, it offers a negative permittivity. The refractive index of BSF is almost zero for 2.45−3.98 GHz range of frequency. The proposed FSS structure exhibits polarization-independent properties and offers a stable frequency response for normal and oblique angles under both TE and TM polarization. Good agreement between the simulated and measured results is obtained for the designed prototype. [ABSTRACT FROM AUTHOR]

With the high penetration and flexible access of inverter‐interfaced distributed generators (IIDGs), it is gradually becoming difficult for traditional protection schemes to meet the requirements for the safe operation of distribution networks (DNs). Active protection schemes based on power electronic equipment provide a new approach. On the basis of the controllability of voltage source converters, a method for active high‐frequency signal injection and a selection principle for the corresponding control parameters are proposed. Considering the impact of T‐connected load branches on the protected line, the high‐frequency current characteristics at the three terminals during internal and external faults are analysed. On this basis, an active protection scheme based on high‐frequency current is proposed for DNs with IIDGs. The performance of the proposed scheme is verified via PSCAD/EMTDC simulation software. The test results show that the proposed scheme can reliably trip during internal faults and identify faulty phases, which has better endurance to fault resistance. [ABSTRACT FROM AUTHOR]

The coffee sector in Ethiopia is the livelihood of more than 20% of the population and accounts more than 25% of the country's foreign exchange earnings. Climate change is expected to affect the climatic suitability of coffee in Ethiopia, and this would have implications for global coffee output, the national economy, and farmers' livelihoods in Ethiopia. The objective of this paper is to assess the current and future impacts of climate change on bioclimatic suitability to C.arbica production in Ethiopia. Based on the current distribution of coffee production areas and climate change predictions from HadGEM2 and CCSM2 models and using the Maximum Entropy (MaxEnt) bioclimatic modeling approach, future changes in climatic suitability for C. arabica were predicted. Coffee production sites in Ethiopia were geo-referenced and used as input in the MAXENT model. The findings indicated that climate change will increase the suitable growing area for coffee by about 44.2% and 30.37% under HadGEM2 and CCSM2 models, respectively, by 2080 in Ethiopia. The study also revealed a westward and northwestward shift in the climatic suitability to C. arabica production in Ethiopia. This indicates that the suitability of some areas will continue with some adaptation practice, whilst others currently suitable will be unsuitable, yet others that are unsuitable will be suitable for arabica coffee production. These findings are intended to support stakeholders in the coffee sector in developing strategies for reducing the vulnerability of coffee production to climate change. Site-specific strategies should be developed to build a more climate resilient coffee livelihood in the changing climate. [ABSTRACT FROM AUTHOR]

Rubus idaeus is a pivotal cultivated species of raspberry known for its attractive color, distinct flavor, and numerous health benefits. It can be used in pharmaceutical, cosmetics, agriculture and food industries not only as fresh but also as a processed product. Nowadays due to climatic changes, genetic diversity of cultivars has decreased dramatically. However, until now, the status of wild R. idaeus resources in China have not been exploited. In this study, we investigated the resources of wild R. idaeus in China to secure its future potential and sustainability. The MaxEnt model was used to predict R. idaeus suitable habitats and spatial distribution patterns for current and future climate scenarios, based on wild domestic geographic distribution data, current and future climate variables, and topographic variables. The results showed that, mean temperature of the coldest quarter (bio11), precipitation of the coldest quarter (bio19), precipitation of the warmest quarter (bio18), and temperature seasonality (bio4) were crucial factors affecting the distribution of R. idaeus. Presently, the suitable habitats were mainly distributed in the north of China including Xinjiang, Inner Mongolia, Gansu, Ningxia, Shaanxi, Shanxi, Hebei, Beijing, Liaoning, Jilin, Heilongjiang. According to our results, in 2050s, the total suitable habitat area of R. idaeus will increase under SSP1-2.6 and then will be decreased with climate change, while in the 2090s, the total suitable habitat area will continue to decrease. From the present to the 2090s, the centroid distribution of R. idaeus in China will shift towards the east and the species will always be present in Inner Mongolia. Our results provide wild resource information and theoretical reference for the protection and rational utilization of R. idaeus. [ABSTRACT FROM AUTHOR]

We report the discovery of the first fossil of an Australian species of Pergidae, Baladi warru gen. et sp. n., found at McGraths Flat, a newly discovered Miocene Konservat‐Lagerstätte in central New South Wales. Using morphological data from the well‐preserved fossil, along with a previously published molecular dataset of 59 taxa and a newly generated molecular dataset for 8 taxa, we constructed a data matrix and generated the first chronogram for Pergidae that incorporates internal calibration points. Our data reveal that Baladi warru belongs to the subfamily Perginae and is closely related to the Australian genera Cerealces and Xyloperga (tribe Cerealcini). According to our analysis, the origin of Pergidae appears slightly younger than previously hypothesised; however, additional calibration points are needed for a more detailed age constraint. Furthermore, ancestral character reconstruction indicates four independent adaptations to toxic Myrtaceae as host plants, while biogeographic analyses suggest that sympatry followed by founder events were the primary processes shaping the current disjunct distribution of pergids. Two significant founder events correspond with transitions to utilising Myrtaceae as host plants. With the approval of the Mudgee Local Aboriginal Land Council, Wiradjuri words were used to name the newly described species. ‘Baladi’ means ‘saw’ and ‘warru’ means ‘wasp’. This name honours the Traditional Owners of the lands on which the fossil was collected. [ABSTRACT FROM AUTHOR]

Solid oxide fuel cell (SOFC) has attracted wide attention because its efficiency is not limited by the efficiency of Carnot cycle. The structure of flow channel in SOFC has great effects on the internal mass distribution, which influences current density. In this paper, the height of flow channel and the position, arrangement, number and height of the fin which is placed in channel, are changed to get different structures of bi-layer interconnector, and they are applied to three layers SOFC stack. The effects of each structural parameter on the current density are studied by numerical simulation. The results show that, increasing the number of fins and bi-layer interconnector height can make more reactant gas enters the electrode. In addition, compared with the conventional structure, the current density can be increased by the bi-layer interconnector up to 31.256%, and the bi-layer interconnector structure could save n-1 layers of interconnector, which reduces the volume of SOFC stack. Among the five structural parameters, the position of fins has the least influence on temperature distribution and current density, while the arrangement of fins has the highest influence on volume current density, reaching 30%. Using a staggered arrangement and higher bi-layer interconnector can also improve the temperature distribution. • A three-dimensional SOFC stack with bi-layer interconnector was established. • Changing geometry of fins and channel height to get different structures. • Increasing number of fins and channel height improve concentration distribution. • The arrangement of fins has the greatest impact on current density. • Staggered fins and higher bi-layer interconnector reduce the highest temperature. [ABSTRACT FROM AUTHOR]

Bipolar plates (BPPs) and membrane electrode assemblies (MEAs) are the key components for proton exchange membrane fuel cells (PEMFCs), they are alternately arranged to construct a compact stack with high power generation. This stacking method may introduce several issues, such as the difficulties in maintenance, imprecise assembly and sealing. This paper presents a novel integrated packaged single fuel cell that employs titanium metal bipolar plates to construct a short stack with superior sealing performance and working reliability. To predict the performance of integrated packaged single cell, numerical model was developed to analyze the mass transfer of O 2 , H 2 and H 2 O within the cell, revealing a uniform distribution of reactants and current. A short stack was manufactured with 10 layers of single cells, it retains excellent sealing properties and consistent output across a range of pressure conditions, with a leakage rate deviation lower than 0.03 mL/(min·cell) and membrane current density variation less than 5%. Finally, the electrochemical performance of the integrated packaged short stack was tested, its maximum power is 886.67 mW/cm2. It can achieve a rated output power of 169.14 W and an energy density of 1684.97 mW/cm3. Thus, our developed short stack has high energy utilization efficiency for power generation, and is anticipated to provide a durable power source for drones, robots and new energy vehicles. • An integrated packaged single fuel cell short stack based on titanium metal polar plates was proposed. • Numerical model of single cell was established, simulation on gas molar concentration and current density distribution was conducted. • A 10-layer integrated short stack was fabricated, assembly stress and polarization tests verified its good sealing performance. [ABSTRACT FROM AUTHOR]

Proton exchange membrane fuel cell (PEMFC) with dead-ended anode (DEA) suffers from nitrogen diffusion and water accumulation, leading to unstable performance. The core of this paper is to enhance the stability of DEA operation. By coupling the flow field structure with the DEA mode, the factors affecting the stability are explored, the performance degradation mechanism after DEA operation is revealed, and the purging strategy is formulated by combining the energy management with the voltage stability as a prerequisite. The experimental results show that the serpentine flow field is advantageous for maintaining the most stable DEA operation with a minimum voltage recession of 17.01 mV and a voltage undershoot of 11.63 mV. The local current density distribution exhibited a pattern of highest values at anode inlet and lowest at anode outlet, which could be improved by increasing operating pressure and reducing load current density. In this experiment, PCB was innovatively combined to investigate the degradation of each region of PEMFC after 60h of DEA operation. It is found that the most severe performance degradation occurs in anode outlet with a degradation rate exceeding 50%, while the center area has a degradation rate of no more than 20%. • The flow field structures are evaluated for the most stable DEA operation. • Experimentally investigated the stability of DEA operation based on PCB segmented cell technology. • The optimized purging strategy is formulated to maintain the stability operation with high output energy. [ABSTRACT FROM AUTHOR]

The coupling effects of clamping pressure and catalyst distribution are comprehensively considered to improve proton exchange membrane fuel cell (PEMFC) performance. Numerical models were constructed to study the performance changes and the corresponding internal states of PEMFC under different clamping pressures. Since the increased clamping pressure reduces the uniformity of current density, non-uniform designs with decreased catalyst loading under channel and increased catalyst loading under rib are proposed for performance improvement. A weighted objective function considering current density magnitude and uniformity was constructed, and the performances of different catalyst loading distributions were analyzed. Compared to the uniform distribution, the optimized distribution with a variation of −15% and 15% under channel and rib had the maximum objective function value of 17.24%. The deformation analysis of the gas diffusion layer and optimization of catalyst loading distribution based on deformation analysis provided a reference for the assembly of PEMFC and the production of MEA. [ABSTRACT FROM AUTHOR]

Ultra-high-pressure tubular reactors are crucial pieces of equipment for polyethylene production. Long-term operation under high temperature, high pressure, and other extremely harsh conditions can lead to various defects, with circumferential cracks posing a major safety risk. Detecting cracks is challenging, particularly when they are under a protective layer of a certain thickness. This study designed a pulsed eddy current differential probe to detect circumferential cracks in ultra-high-pressure tubular reactors, with the lift-off distance acting as a protective layer. Detection models for traditional cylindrical and semi-circular excitation differential probes were established using finite element simulations. Corresponding experiments under different lift-off conditions were carried out, and the model's accuracy was verified by the consistency between the simulation results and experimental data. The distribution of the eddy current field under different conditions and the disturbances caused by cracks at various positions to the detection signal were then calculated in the simulations. The simulation results showed that the cracks significantly disturbed the eddy current field of the semi-circular excitation differential probe compared with that of the traditional cylindrical probe. The designed differential probe effectively detected circumferential cracks of specific lengths and depths using the difference in the voltage signals. The experimental results were in agreement with the simulation results, showing that the designed probe could effectively detect 20 mm-long circumferential cracks at a lift-off of 60 mm. The experimental results also show that the probe's detection coverage area in the axial direction varied with the lift-off height. The probe design and findings are valuable for detecting cracks in ultra-high-pressure tubular reactors with protective layers. [ABSTRACT FROM AUTHOR]

This paper introduces a novel finite control set predictive direct power control method for grid‐connected converters without cost function evaluations. Unlike conventional predictive direct power control, since the proposed method does not use the model parameters, their uncertainties do not cause prediction error and inappropriate voltage vector selection. The method employs a new form of voltage vector selection based on the slopes of active and reactive powers. The slopes are predicted in a manner with a low sensitivity to sampling noise, without updating a look‐up table, and recursive methods. Hence, there are no stagnation and convergence issues. Also, the proposed method avoids startup problems caused by data‐lacking due to directly regulating the active and reactive power by a switching logic. Flexible power oscillations control with balanced sinusoidal grid currents without any signal sequence extraction can also be achieved under this method in unbalanced grid conditions. The proposed method is assessed by both simulation and experimental studies, and its performance is compared with existing robust combined and model predictive control methods. The outcomes highlight the influence of the proposed approach and establish its superiority over the other considered methods. [ABSTRACT FROM AUTHOR]

Global climate change is one of the most critical challenges facing natural ecosystems. As sedentary organisms, plant communities are especially vulnerable, with climate change significantly impacting their development, productivity, and distribution. This study focuses on modelling and mapping the potential distribution of black pine (Pinus nigra) within the Antalya Regional Forest Directorate under the SSP1 2.6 climate scenario for the years 2040, 2060, 2080, and 2100. The MaxEnt modelling method, combined with the HadGEM3-GC31-LL climate model from WorldClim, was used to assess the impact of climate change on black pine. The current distribution model results showed "good" predictive performance, with AUC values of 0.855 for training data and 0.851 for testing data. Key variables influencing the model included precipitation during the wettest quarter, annual precipitation, maximum temperature of the warmest month, and elevation. Projections indicate that the black pine's distribution will shrink by 2040, become increasingly fragmented by 2060, and decline further by 2080, with near-total disappearance by 2100. In conclusion, this study highlights the urgent need for adaptive management strategies to address the effects of climate change on black pine forests. [ABSTRACT FROM AUTHOR]

The North Pacific distribution of coastal staphylinids may be explained as the result of either dispersal or vicariance. The intertidal rove beetle genus Diaulota is a submarine group that occurs on the Pacific coasts of the Northern Hemisphere. We performed a phylogenetic analysis of Diaulota using molecular characters (3241 bp) to investigate their biogeographic history and patterns. The data were analysed by parsimony, Bayesian, and maximum likelihood methods. Model-based analyses showed the same pattern of Diaulota species relationships, but parsimony analysis resulted in different species relationships for the unresolved clade B. Biogeographical analyses suggested that the common ancestor of Diaulota occurred widely along the East Asian coast with repeated dispersal to the north-eastern Pacific from the north-western Pacific. According to the reconstruction of the ancestral areas, both dispersal (seven events) and vicariance (four events) were important in shaping its current distribution. Although most species underwent stepwise colonization from East Asia via Kamchatka and Alaska to North America along the coast, a single lineage (Diaulota fulviventris and Diaulota harteri) crossed the Pacific Ocean directly from the north-western Pacific to the north-eastern Pacific, possibly via sea surface currents. [ABSTRACT FROM AUTHOR]

This paper presents an ultra-wideband polarization converting metasurface (PCM) for millimeter wave which can manipulate the linear polarized (LP) incident wave to its orthogonal counterpart in the frequency range of 49.7 to 142.2 GHz with an ultra-wide bandwidth of 92.5 GHz and a fractional bandwidth (FBW) of 96%. The proposed PCM shows outstanding results in achieving higher fractional bandwidth with overall polarization conversion ratio (PCR) > 90% in the desired band. The proposed PCM has low profile dimensions with thickness and periodicity of 0.5 mm (0.083 λo) and 1.43 mm (0.24 λo), where λo is the maximum wavelength at the lower operating frequency. Surface current distribution is studied to show the physics of polarization conversion. The design is versatile and adoptable in low-profile applications where minimum thickness is required and can be utilized in remote sensing, microwave relays, and astronomy. [ABSTRACT FROM AUTHOR]

A new microstrip patch antenna design with a dual-wing construction is introduced to provide diverse multiband characteristics maintaining good antenna performance. The antenna exhibits resonances at multiple frequencies within the X-band due to the use of etched slots on the parasitic patch, considerably broadening its possible applications. This unique configuration is thoroughly investigated using numerical simulations as well as real testing. The proposed design showcases three distinct operational bands, operating at frequencies of 8.32 GHz, 10.33 GHz, and 11.69 GHz. These bands are supported by impedance bandwidths of 300 MHz (ranging from 8.21 to 8.51 GHz), 620 MHz (from 10.01 to 10.63 GHz), and 510 MHz (covering from 11.4 to 11.91 GHz). Furthermore, the antenna delivers favorable gains of 3.31 dB, 7.78 dB, and 7.48 dB at their respective frequencies. A commercially accessible electromagnetic simulation tool is used to simulate the antenna's design. This tool accurately predicts and analyses the performance of the antenna, validating simulated results with the experimental findings. The antenna has compact dimensions of 38 × 38 × 1.6 mm3 due to its unique design, which contributes to multiband capabilities and enhanced bandwidth. The antenna's wing form improves radiation patterns and surface current distribution. The directional flow of currents in distinct modes is recognizable at the three operational frequencies. This novel antenna design holds promise for applications demanding multiband capabilities and enhanced performance. [ABSTRACT FROM AUTHOR]

Climate change has a pivotal impact on the potential distribution of endangered and relic tree species. Probably due to unrepresentative sampling and single algorithm, at present, there are different views on the potential range of the endangered tree Emmenopterys henryi, endemic to China. Here, we first collated 612 occurrence records and 22 environmental variables including climate, topography, and soil. Combined the Biomod2 with MaxEnt, we then predicted its past, current, and future potential suitable area in China, and determined the key factors influencing its distribution. The ensemble model results showed that the main environmental variables affecting this species were the minimum temperature of the coldest month (BIO6), precipitation of warmest quarter (BIO18), and temperature seasonality (BIO4). Its current potential distribution area was 176.53 × 104 km2, mainly concentrated in eastern, central, and southwestern China. Collectively, the suitable area of E. henryi would averagely decrease by 3.90% in all 16 future scenarios, with its centroid largely migrating northeastward. Our findings indicate that the endangered E. henryi covered 18 provinces in China, having a larger area than known. Moreover, climate change may have an adverse effect on its potential distribution. In addition, the ensemble model can produce more effective prediction outcomes than MaxEnt for such endemic tree species with large environmental range. We recommend increasing sample representativeness by analyzing the completeness properties of sample coverage, and simultaneously selecting appropriate algorithms to ensure the reliability of distribution prediction for endangered and relict tree species. [ABSTRACT FROM AUTHOR]

Species distribution models (SDMs) are widely used to project how species distributions may vary over time, particularly in response climate change. Although the fit of such models to current distributions is regularly enumerated, SDMs are rarely tested across longer time spans to gauge their actual performance under environmental change. Here, we utilise paleozoological presence/absence records to independently assess the predictive accuracy of SDMs through time. To illustrate the approach, we focused on modelling the Holocene distribution of the hartebeest, Alcelaphus buselaphus, a widespread savannah‐adapted African antelope. We applied various modelling algorithms to three occurrence datasets, including a point dataset from online repositories and two range maps representing current and 'natural' (i.e. hypothetical assuming no human impact) distributions. We compared conventional model evaluation metrics which assess fit to current distributions (i.e. True Skill Statistic, TSSc, and Area Under the Curve, AUCc) to analogous 'paleometrics' for past distributions (i.e. TSSp, AUCp, and in addition Boycep, F2‐scorep and Sorensenp). Our findings reveal only a weak correlation between the ranking of conventional metrics and paleometrics, suggesting that the models most effectively capturing present‐day distributions may not be the most reliable to hindcast historical distributions, and that the choice of input data and modelling algorithm both significantly influences environmental suitability predictions and SDM performance. We thus advocate assessment of model performance using paleometrics, particularly those capturing the correct prediction of presences, such as F2‐scorep or Sorensenp, due to the potential unreliability of absence data in paleozoological records. By integrating archaeological and paleontological records into the assessment of alternative models' ability to project shifts in species distributions over time, we are likely to enhance our understanding of environmental constraints on species distributions. [ABSTRACT FROM AUTHOR]

Simple Summary: The water primrose (Ludwigia peploides) is believed to have been planted as an ornamental aquatic plant in South Korea. It spread to natural ecosystems through rivers, and its distribution is gradually expanding in Suwon, Hwaseong, Busan, and Jeju. However, there has been no specific study on the ecological risk of L. peploides introduced into South Korea. This study, therefore, investigates the distribution status and ecological risks of L. peploides in South Korea through field surveys and allelopathic material analysis, as well as assessing abiotic risk factors. The distribution was confirmed at a total of 19 sites. The species was observed to primarily inhabit aquatic environments but were also observed to inhabit moist terrestrial areas such as riverbanks or wet grasslands. The results of this study are expected to aid in the identification of the current distribution and potential ecological risks of L. peploides in South Korea, providing vital information for the development of effective management strategies. The number of alien species introduced into South Korea continues to increase over the years. In particular, several plants have been introduced as ornamentals. Ludwigia peploides, which is native to the Americas and Australia, is believed to have been planted as an ornamental aquatic plant called "water primrose" and "primrose". It spread to natural ecosystems through rivers, and its distribution is gradually expanding in Suwon, Hwaseong, Busan, and Jeju. However, there has been no specific study on the ecological risk of L. peploides introduced into South Korea. This study, therefore, investigates the distribution status and ecological risks of L. peploides in South Korea through field surveys and allelopathic material analysis, as well as assessing abiotic risk factors. The distribution was confirmed at a total of 19 sites, with high-density mats of a single species forming along the water's edge and on the water surface. The maximum distribution area was 13,922 m2 in Chilgok Reservoir in Anseong. Stems and plant fragments transported along waterways were continuously forming colonies through vegetative propagation. When evaluating the overall risk, it is determined that L. peploides has a high potential to cause significant damage to the ecosystem if not managed promptly. Therefore, continuous monitoring is necessary to effectively manage and prevent the habitat expansion of L. peploides. The results of this study are expected to aid in the identification of the current distribution and potential ecological risks of L. peploides in South Korea, providing essential data for ecological risk assessment and the development of effective management strategies. [ABSTRACT FROM AUTHOR]

Background: The study focuses on thermal management in tumor‐treating fields (TTFields) therapy, crucial for patient compliance and therapeutic effectiveness. TTFields therapy, an established treatment for glioblastoma, involves applying alternating electric fields to the brain. However, managing the thermal effects generated by electrodes is a major challenge, impacting patient comfort and treatment efficiency. Purpose: This research aims to explore methods for controlling temperature increases during TTFields therapy without reducing its duty cycle. The study emphasizes optimizing electrode configurations and array arrangements to mitigate temperature rise, thereby maintaining therapy effectiveness and patient compliance. Methods: Using a simplified multi‐layer tissue model and finite element analysis, various electrode configurations and array shapes were tested in COMSOL Multiphysics v6.0. Adjustments included changing the electrode gel layer radius from 8 to 12 mm, electrode spacing, and transitioning to a more uniform array arrangement, such as a square array or a circular array. Results: The study revealed a strong correlation between high temperatures and edge current density distributions on electrodes. It was found that increasing the electrode gel layer's diameter, enlarging electrode spacing, and adopting a uniform array arrangement markedly mitigated temperature rises. By increasing the gel layer radius from the original 10 to 12 mm, a reduction in the peak temperature increases of approximately 0.3°C was observed. Changing the layout from rectangular to circular with the same area further reduced the peak temperature rise by 0.5°C. Additionally, enlarging the spacing between electrodes also contributed to temperature control. By integrating these strategies, we designed a new circular electrode array with an electrode spacing of 45 mm and a gel radius of 12 mm, successfully reducing the peak temperature from 42.1°C to 40.8°C, effectively achieving temperature control. Conclusions: The research demonstrates that improving electrode and array configurations can effectively manage temperature in TTFields therapy without compromising treatment duration. This strategy is crucial as TTFields therapy relies on prolonged field exposure for effectiveness. The findings offer valuable insights into thermal management in electrode array design and could lead to enhanced patient compliance and treatment efficacy in TTFields therapy. [ABSTRACT FROM AUTHOR]

Simple Summary: The Syringophilidae family is one of the most diverse groups of prostigmatic mites (Acari: Prostigmata) parasitising birds. In this paper, we describe a new genus and species, Corvisyringophilus krummi, which parasitises the Common Raven (Corvus corax) in Iceland. This new genus belongs to a group of primitive genera that retain a complete set of idiosomal and leg setae. Our phylogenetic analysis suggests that Corvisyringophilus is morphologically closely related to the genera Blaszakia Skoracki & Sikora, 2008 and Charadriphilus Bochkov & Mironov, 1998, which are associated with birds of different and phylogenetically unrelated orders: Musophagiformes and Charadriiformes, respectively. This research highlights the importance of examining the genus Corvus in order to better understand the specialised host–parasite relationships. Furthermore, the study emphasises the significance of using museum collections to study parasitic interactions. Syringophilidae is one of the most species-rich families in the superfamily Cheyletoidea, comprising approximately 420 species across 62 genera and two subfamilies. In this paper, we propose a new genus, Corvisyringophilus, and a new species, C. krummi gen. n. et sp. n., found in the wing covert quills of the Common Raven, Corvus corax Linnaeus, in Iceland. Corvisyringophilus is placed among the primitive genera of syringophilid mites, which possess the full complement of idiosomal and leg setae. Phylogenetic analysis based on morphological characters suggests that this genus forms a sister clade to Blaszakia Skoracki & Sikora, 2008, and Charadriphilus Bochkov & Mironov, 1998, which inhabit birds of the orders Musophagiformes and Charadriiformes, respectively. The study proposes that the current distribution patterns of quill mites, based on their morphological characteristics, may result from multiple host switching followed by co-speciation events, highlighting the complex evolutionary dynamics within this family. [ABSTRACT FROM AUTHOR]

Background: Madariaga virus (MADV), a member of the eastern equine encephalitis virus (EEEV) complex, circulates in Latin America and exhibits distinct evolutionary and ecological features compared to the North American EEEV. While published data have shed light on MADV ecology, several key aspects remain unknown. Methods: In this study, we compiled data on virus isolation, vector competence, and animal serology collected over six decades in Latin America to identify critical knowledge gaps on MADV transmission and ecology. Results: Specific vertebrate animals serving as amplifying hosts and the mosquito species acting as enzootic and epizootic vectors have not yet been identified. Other aspects that remain unclear are the virus current geographic distribution, the role of equines as hosts in epizootic cycles, and the full impact of MADV on human health in endemic regions. Conclusions: The numerous knowledge gaps surrounding MADV, its widespread distribution in Latin America, and its potential to cause severe disease in animals and humans emphasize the urgent need for increased research efforts, heightened awareness, and intensified surveillance towards this potential emerging threat. [ABSTRACT FROM AUTHOR]

Resolving laser-driven electron dynamics on their natural time and length scales is essential for understanding and controlling light-induced phenomena. Capabilities to reveal these dynamics are limited by challenges in interpreting wave mixing of a driving and a probe pulse, low energy resolution at ultrashort time scales and a lack of atomic-scale resolution by standard spectroscopic techniques. Here, we demonstrate how ultrafast x-ray diffraction can access fundamental information on laser-driven electronic motion in solids. We propose a method based on subcycle-resolved x-ray-optical wave mixing that allows for a straightforward reconstruction of key properties of strong-field-induced electron dynamics with atomic spatial resolution. Namely, this technique provides both phases and amplitudes of the spatial Fourier transform of optically-induced charge distributions, their temporal behavior, and the direction of the instantaneous microscopic optically-induced electron current flow. It captures the rich microscopic structures and symmetry features of laser-driven electronic charge and current density distributions. Manipulation of materials properties by laser driving can lead to future technological applications, but a complete picture of its mechanisms is missing. In their paper, authors propose a method based on ultrafast x-ray diffraction that allows for resolving laser-driven electron dynamics on their natural time and length scales. [ABSTRACT FROM AUTHOR]

Fossil bird eggs from the Pleistocene of the Americas are rare. Previous records include Uruguay, Bermuda, California (USA) and Mexico, including reports of complete fossil eggs from extinct puffin (Fratercula dowi) from California, Tinamou (Tinamidae indet.) from Uruguay, Brown Pelican (Pelecanus occidentalis) from Bermuda and Sandhill Crane (Grus canadensis) from México. The fossil record of flamingos in Mexico is restricted to palaeolakes in Central Mexico, which is very interesting because the current distribution of flamingos in North America is restricted to some areas of the Southeastern United States and Yucatan Peninsula, which are far from palaeontological sites. We report a fossil flamingo egg found during the construction of a new International Airport 'Felipe Angeles', Santa Lucía, State of México. This egg is the first Pleistocene fossil egg record for the family Phoenicopteridae, the first fossil egg record of this family in the Americas and the second record of a phoenicopterid fossil egg in the world. We re-identified the fossil eggs described by Martin del Campo in the 1940s, suggesting that they are also flamingo eggs. Using biogeographical and climate niche data for family Phoenicopteridae in North America, we infer the presence of a salinity and shallow palaeolake during the Late Pleistocene, with climatic condition being warmest and wetter than at present. [ABSTRACT FROM AUTHOR]

Decision support systems are being developed to assist clinicians in complex decision-making processes by leveraging information from clinical knowledge and electronic health records (EHRs). One typical application is disease risk prediction, which can be challenging due to the complexity of modelling longitudinal EHR data, including unstructured medical notes. To address this challenge, we propose a deep state-space model (DSSM) that simulates the patient's state transition process and formally integrates latent states with risk observations. A typical DSSM consists of three parts: a prior module that generates the distribution of the current latent state based on previous states; a posterior module that approximates the latent states using up-to-date medical notes; and a likelihood module that predicts disease risks using latent states. To efficiently and effectively encode raw medical notes, our posterior module uses an attentive encoder to better extract information from unstructured high-dimensional medical notes. Additionally, we couple a predictive clustering algorithm into our DSSM to learn clinically useful representations of patients' latent states. The latent states are clustered into multiple groups, and the weighted average of the cluster centres is used for prediction. We demonstrate the effectiveness of our deep clustering-based state-space model using two real-world EHR datasets, showing that it not only generates better risk prediction results than other baseline methods but also clusters similar patient health states into groups. [ABSTRACT FROM AUTHOR]

Centralisation of perioperative care for small children to a limited number of specialised paediatric centres has many theoretical advantages, but neither the optimal balance nor the current distribution of paediatric anaesthesia on a national scale are well elucidated. The aim of this study was to describe the distribution, adverse events, and mortality in children undergoing anaesthesia in Sweden. In this cohort study, data from all paediatric anaesthesia procedures registered in Sweden during the years 2019–22 were extracted from the Swedish Perioperative Register (SPOR). Data were analysed according to hospital level of care and ASA physical status. Data from 81 hospitals were analysed. During the 4-yr period, 214,964 procedures were registered. Most procedures in neonates and infants were managed in paediatric (73%) and other university hospitals (21%). Adverse events occurred in 2.71% of cases and severe adverse events in 0.067%. The all-cause 24-h mortality rate was 6.6:10,000 anaesthetics and the all-cause 30-day mortality was 14.7:10,000 anaesthetics. The 30-day all-cause estimated mortality was highest in paediatric hospitals (95% confidence interval [CI] 30–39) compared with other university hospitals (95% CI 6.1–12), county (95% CI 1.9–4.8), district (95% CI 0.07–2.2), and smaller hospitals (95% CI 0.0–22). Most procedures in neonates and infants were performed in tertiary centres, with county hospitals managing mainly older children, in accordance with national recommendations. Mortality was more common in tertiary centres, reflecting increased comorbidity and centralisation of anaesthesia of neonates and infants. [ABSTRACT FROM AUTHOR]

The olive is an economically important and indispensable species of the Mediterranean basin with remarkable historic and cultural significance. Wild olives constitute a priceless reservoir of genetic diversity which has great value for olive breeding and conservation programs. However, global climate changes especially global warming is expected to threaten olive cultivation in future causing large economic loses in the region. Therefore, knowledge about distribution and abundance of wild olive populations is important to maximize their conservation, safeguard, and exploitation. Muğla province, where the wild olives make up an important part of the vegetation, is one of the main olive producing area in Turkey with many towns and villages dependent on the olive. In this study, our aim is to examine the current geographical distribution and density of wild olive populations in this province and the 82 islands around its coast. The results demonstrated that young olives, which show good adaptation to region, just have started to expand to the higher parts of the Kavaklıdere district. In addition, in most of the islands wild olives are preserved in their undisturbed natural habitats where they exist as small groves or scattered plants. The results of this study provides important insights for the conservation of wild olive genetic resources. The data reported here, are based on actual field data thus the geographic coverage tends to be complete and consistent. [ABSTRACT FROM AUTHOR]

Atlantic White Cedar (Chamaecyparis thyoides) (AWC) anchors a globally threatened ecosystem that is being impacted by climate change, as these trees are vulnerable to hurricane events, sea-level rises, and increasing salinity at the forest–marsh ecotone. In this study, we determined the current amount and distribution of AWC in an area that is experiencing sea-level rises that are higher than the global average rate. We used a combination of a field investigation and aerial photo interpretation to identify known locations of AWC, then integrated Sentinel-1 and 2A satellite data with abiotic variables into a species distribution model. We developed a spectral signature of AWC to aid in our understanding of phenology differences from nearby species groups. The selected model had an out-of-bag error of 7.2%, and 8 of the 11 variables retained in the final model were derived from remotely sensed data, highlighting the importance of including temporal data to exploit divergent phenology. Model predictions were strong in live AWC stands and, accurately, did not predict live AWC in stands that experienced high levels of mortality after Hurricane Sandy. The model presented in this study provides high utility for AWC management and tracking mortality dynamics within stands after disturbances such as hurricanes. [ABSTRACT FROM AUTHOR]

This paper proposes a novel THz band 2-D wide-angle scanning phased-array antenna (PAA) based on a decoupling surface. The simulated S11 bandwidth under periodic boundary conditions is 106–119 GHz, with stable gain within the bandwidth. The designed decoupling surface effectively reduces the coupling between elements, and the simulated active VSWR performance and ground surface current distribution under periodic boundary conditions confirm this. An 8 × 8 (64-element) planar PAA is modeled and simulated in CST2022 to verify the beam-scanning performance of the PAA. According to the simulation results, a 2-D wide-angle scanning of ±48° is achieved in the 106–114 GHz range, while in the 115–119 GHz range, a wide-angle scanning of ±48° is achieved on the E-plane, and the beam-scanning range on the H-plane reaches ±40°. Moreover, the normal peak gain is stably maintained at 21.9–22.8 dBi, with a normalized radiation efficiency as high as 95%, and the scanning radiation efficiency is higher than 81%. Due to its stable gain and 2-D wide-angle scanning performance, the proposed PAA has a broad application prospect in terahertz wireless communication equipment. [ABSTRACT FROM AUTHOR]