Static Index Research Articles

A New Perspective of Trees Competition Network Research

Forest competition is a key factor driving forest dynamics and stand structure, and is one of the core issues in ecological research. Competition is a complex ecological process with temporal changes, which is interrelated and affected with forest growth, stand structure dynamics and environmental changes. Although there have been many researches on competition, tree growth, stand structure and climate, the interactions among trees have been studied by static competition index measurement, which usually lacks temporal variation related to natural forest development and environmental conditions, and the response mechanism and related theory of competition to stand development and environmental fluctuation have been studied insufficiently.(2) Single tree competition index model;(3) Interaction between tree competition and tree growth, stand structure and environment;(4) Tree competition based on complex network. Finally, according to the complex interaction of tree competition, the research strategy of tree competition network structure with “single tree” as node and “single tree competition relationship” as edge is discussed, in order to provide reference for the study of tree interaction and forest ecosystem dynamics.

Twistronics in two-dimensional transition metal dichalcogenide (TMD)-based van der Waals interface.

Transition metal dichalcogenides (TMD) based heterostructures have gained significant attention lately because of their distinct physical properties and potential uses in electronics and optoelectronics. In the present work, the effects of twist on the structural, electronic, and optical properties (such as the static dielectric constant, refractive index, extinction coefficient, and absorption coefficient) of vertically stacked TMD heterostructures, namely MoSe2/WSe2, WS2/WSe2, MoSe2/WS2 and MoS2/WSe2, have been systematically studied and a thorough comparison is done among these heterostructures. In addition, the absence of negative frequency in the phonon dispersion curve and a low formation energy confirm the structural and thermodynamical stability of all the proposed TMD heterostructures. The calculations are performed using first-principles-based density functional theory (DFT) method. Beautiful Moiré patterns are formed due to the relative rotation of the layers as a consequence of the superposition of the periodic structures of the TMDs on each other. Twist engineering allows the modulation of bandgaps and a phase change from direct to indirect band gap semiconductors as well. The high optical absorption in the visible range of spectrum makes these twisted heterostructures very promising candidates in photovoltaic applications.

Влияние низкотемпературного отжига неупорядоченных плёнок Ge10Se90 на их оптические свойства

In the present paper, the effect of low-temperature annealing on the linear optical properties of disordered thin films (~350 nm) synthesized from Ge10Se90 glass by vacuum thermal evaporation on quartz substrates is reported. Based on the experimental transmission spectra of films in the field of optical transparency before and after annealing below and at the glass transition temperature Tg = (3612) K (313 and 363 K, respectively), the main optical characteristics (dispersion dependences of the refractive index and extinction coefficient, optical gap energy, the Tautz parameter B1/2, etc.) were determined using the Swanepoel and Tautz methods. It is revealed that the edge of optical absorption in the annealed films is caused by indirect optical transitions. Using the Wemple-DiDomenico single oscillator model, the Urbach energy EU, the energy of one oscillator E0, the scattering energy Ed, the linear susceptibility  and the static refractive index n0 were calculated. At the same time, a higher value of the Ed/E0 ratio of the film annealed at Tg indicates its greater nonlinear susceptibility. The X-ray diffraction studies have confirmed the amorphous nature of the initial films and the appearance of Se nanocrystallites in them after annealing of a certain polymorphic modification depending on the temperature and time of annealing. It was found that annealing both below Tg and at Tg initiates red shift in the optical absorption edge, an increase in EU and , and a decrease in the thickness of the film and the parameter B1/2. It is shown that the annealing of identical films is accompanied by a change in their phase composition with the appearance of either monoclinic beta-Se8 nanocrystallites or the mixture of beta-Se8 and trigonal t-Se. From the standpoint of the concept of the polymerpolymorphoid structure of glass and a glass-forming liquid, it is due to the mutual transformation of polymorphoids of various polymorphic modifications because of a change in their concentration ratio depending on the annealing temperature relative to Tg. The resulting films can be used in optoelectronics as nonlinear optical elements or media for radiation limiters.

The spectral properties and dispersion parameters of electrospun nanofibers Poly(vinyl alcohol/ Poly(acrylamide)

Electrospun nanofibers based on polyvinyl alcohol (PVA), polyacrylamide (PAAm), and a PVA-PAAm blend (50/50 wt.%) were effectively made a room temperature(RT) and a voltage of (12kV). The products were studied using Field Emission Scanning Electron Microscope (FESEM), X-ray diffraction (XRD), Fourier-transform infrared spectroscopy(FT-IR) and Ultraviolet-visible (UV–Vis) spectroscopy. The result of FESEM analysis showed that the polymer PVA, PAAm, and blend samples produced a random distribution of fine fibres at an average diameter of (214.12, 317.1, 157.65) nm with a smooth surface. In addition, the FESEM images demonstrate the fibres' suitability for use in gas sensing applications due to their branching fibres and porosity surface. XRD showed that the film polymeric of PVA, PAAm polymeric blend PVA-PAAm was seen to have a semicrystalline nature. According to the FTIR analysis, the PVA and PAAm networks in the PVA-PAAm polymer nanofibers were entangled due to the powerful hydrogen bond contact between the PAAm and PVA chains. Observed around (3473.79 and 3414) cm-1 were attributed to the N–H vibration and overlapped to O–H stretching. The spectra of the prepared films exhibit prominent absorption peaks, which are at the wavelength range (200-320) nm. PVA-PAAm polymer nanofibers decrease the energy gap from 3.70eV to 3.40eV. The Wemple-DiDomenico model was used to derive dispersion parameters such as dispersion energy, single oscillator energy, Urbach energy, the static refractive index and the moments of optical spectra the result of calculating by this model was compatible with that value calculated by the Tauc relation. While increased which qualifies them to be used in the electronic devices.

Mid-Infrared (MIR) Complex Refractive Index Spectra of Polycrystalline Copper-Nitride Films by IR-VASE Ellipsometry and Their FIB-SEM Porosity

Copper-nitride (Cu3N) semiconductor material is attracting much attention as a potential, next-generation thin-film solar light absorber in solar cells. In this communication, polycrystalline covalent Cu3N thin films were prepared using reactive-RF-magnetron-sputtering deposition, at room temperature, onto glass and silicon substrates. The very-broadband optical properties of the Cu3N thin film layers were studied by UV-MIR (0.2–40 μm) ellipsometry and optical transmission, to be able to achieve the goal of a low-cost absorber material to replace the conventional silicon. The reactive-RF-sputtered Cu3N films were also investigated by focused ion beam scanning electron microscopy and both FTIR and Raman spectroscopies. The less dense layer was found to have a value of the static refractive index of 2.304, and the denser film had a value of 2.496. The iso-absorption gap, E04, varied between approximately 1.3 and 1.8 eV and could be considered suitable as a solar light absorber.

Optical studies on thermally evaporated Ge–Se/Ge-Sb-Se chalcogenide glass films by spectroscopic ellipsometry

The GexSb30-xSe70: x = 30, 25, 15, 10 glass films were prepared by thermal evaporation technique. The surface morphology of glass films was studied by atomic force microscopy. The samples exhibited surface roughness with a root mean square value falling within the 0.89–1.47 nm range. The optical properties were precisely characterized by spectroscopic ellipsometry in the 4.13–0.77 eV spectral range. The Cody-Lorentz dispersion model was used to fit the data across the entire spectral range and extract the optical functions of glass films. It has been observed that the refractive index, n values rise with increasing energy, reaching a peak, and then experience a subsequent decline. The refractive index values exhibit a rising trend with an increase in Sb content. The optical bandgap, Egopt was found to follow a decreasing pattern with a decrease in Ge content. The refractive index dispersion curve was analyzed using the Wemple and DiDomenico single oscillator model in the lower absorption spectral region. It has been observed the values of oscillator energy, Eo, and static refractive index, n0, exhibit a pattern consistent with that of Egopt , and n, respectively. The optical properties, such as the high-frequency dielectric constant, carrier concentration, plasma frequency, and optical conductivity were analyzed.

Research on indoor thermal comfort of expressway service building based on SPMV

According to the characteristics of “temporary stay” and “streamlined” passenger flow in expressway service buildings, this article uses the “streamlined thermal comfort” index to characterize the indoor thermal comfort condition of the buildings,to create an overall comfortable space based on the “streamline trajectory”.The article proposes to divide comprehensive thermal comfort into “regional static thermal comfort” and “inter-zone dynamic thermal comfort”, revise the existing PMV(Predicted Mean Vote) index, and integrate the characteristics of the two types of indicators to form a comprehensive thermal comfort evaluation index based on “passenger trajectory”. The main work of this article includes: Firstly, using the temperature frequency method, a regression curve fitting between actual thermal sensation and indoor operative temperature is conducted to obtain the acceptable thresholds of MTS(Median Thermal Sensation), PMV neutral temperature, and actual temperature, forming a streamlined static thermal comfort index. The metabolic rate M value is segmented according to a 6-minute stabilization time to form a streamlined dynamic thermal comfort index; Introduce the factor of regional residence time τ to form a comprehensive thermal comfort index for streamlining. Secondly, an empirical analysis was conducted on the revised indicators, and the measured TSV(Thermal Sensation Vote) = -1, 0, 1 curves under different operating conditions in summer and winter were fitted with the SPMV(Streamline-Predicted Mean Vote) curve, revealing that the error in each functional area was within 10 %. The analysis results show that the modified index SPMV has greatly improved its consistency with the measured thermal sensation TSV, and can be used to evaluate the indoor thermal comfort of expressway service buildings in cold regions.The research results have high practical value for creating comfortable indoor environments in different indoor spaces of transportation commercial complexes, and have universal significance for creating streamlined indoor dynamic comfortable environments in urban commercial complexes.

Electronic structure, optical and elastic properties of Si doped Strontium Selenide: A theoretical investigation

The structural, electronic, optical, and elastic properties of Silicon doped Strontium Selenide binary and ternary semiconductor alloys with the general form of Sr(1-x)SixSe, 0 ≤ x ≤ 1 in B1 and B3 phases have been figured adopting augmented plane wave plus local orbital methods within density functional theory, Structural properties summarize the crystal structure, relevant atomic positions, lattice constant, bulk modulus minimum energy E0 and minimum volume V0. Elastic constants conform to the structure stability of the B1 and B3 phases. Band gap is found to shift from indirect to direct and in some materials with initial direct band gap, the gap width increased which increased the range of applicability of these binary and ternary semiconductor compounds. Whereas optical properties which include the study of zero frequency limit of static dielectric constant ε0(ω) with its real and imaginary parts, static refractive index n(0), optical reflectivity (R), optical absorption coefficient (α), and loss function (L) studied comprehensively to get real electrical and optical properties of these materials and give semiconductor market best alternative candidate which shows its effectiveness in the visible, ultraviolet and infrared region of the electromagnetic spectrum. The obtained results were compared together and with the available experimental along with theoretical work on these binary and ternary Silicon doped Alkaline earth chalcogenides.

Anisotropic properties of two-dimensional (2D) tin dihalide (SnX2, X = Cl, Br, I) monolayer binary materials

This paper investigated the electronic properties and photoresponse of two-dimensional SnX2 (X = Cl, Br, I) monolayer binary materials using computational techniques. The calculated band structure and density of states indicate that these are large band gap semiconducting materials with an indirect band gap. The studied chemical bonding mechanism shows the existence of the hybrid bonding of ionic and covalent bonds in these dihalide materials. The valence band (VB) and conduction band (CB) edge positions are also estimated, using the concept of electronegativity and band gap, to investigate the photocatalytic activity of SnX2. Next, we investigated the polarization and energy-dependent dielectric and optical functions along the crystallographic axes of these materials in the linear response approach of the perturbing incident oscillating light field. These materials exhibit an anisotropic behavior of these functions, especially in the high-energy visible and low-energy ultraviolet (UV) regions. The absorption of incident light photons is very fast in SnI2 than SnBr2 and SnCl2 in the low-energy UV region. It demonstrates the higher absorption coefficient and optical conductivity in Snl2. The obtained average static refractive index of SnCl2 is comparable to that of glass (1.5), showing its application as transparent material. The low reflection coefficient, less than 20%, makes them superior for antireflection coating materials in the infrared and visible regions. The prominent energy loss peaks show the existence of plasmon resonances in these materials. The most of losses occur in the UV region. The investigated electronic and photoresponse properties indicate that these Sn-based dihalide materials are excellent for electronic devices and optoelectronic applications. Also, the calculated VB and CB edge positions with respect to the normal hydrogen electrode show the favorable water-splitting capability of these materials.

Crystal structure, mechanical, electronic, optical and thermoelectric characteristics of Cs2MCl6 (M = Se, Sn, Te and Ti) cubic double perovskites

The crystal structure, mechanical, electronic, optical and thermoelectric characteristics of Cs2MCl6 (M = Se, Sn, Te and Ti) cubic double perovskites are studied within GGA, GGA-mBJ and EV-GGA functionals. The M − Cl bond lengths are shorter and especially in Cs2TiCl6 double perovskite, which reflects the strong interaction between M and Cl atoms and this is correlated with its better chemical stability. The negativity of formation energy and Helmholtz free energy and no imaginary phonon modes throughout the Brillouin zone confirm the thermal, thermodynamic and dynamical stability of these double perovskites. Semiconductors Cs2MCl6 (M = Se, Sn, Te and Ti) double perovskites with flat conduction and valence bands, and an indirect band gap are p-type carriers. A high Seebeck coefficient, adequate ZT values ​​and non-toxicity make these compounds attractive for thermoelectric applications at high temperature and spintronic technology. The empty first conduction band corresponds to their band gap, and the transition occurs from Cl-p to (Se-p, Sn-p, Te-p and Ti-d). The high static dielectric constant and the intense peak of the real part in the ultraviolet energy range favor less the recombination rate of charge carriers and their use in optoelectronic devices. The indirect band gap, high absorption in ultraviolet energy, high static refractive index make these cubic double perovskites as ideal materials for solar cell applications.

Analysis of Spatio-temporal Characteristics of Air Quality, Meteorological Impact, and Emission Reduction Effect During the Winter Olympics in Beijing-Tianjin-Hebei and Its Surrounding Areas

From January 31st to February 20th, 2015 to 2022, the spatio-temporal characteristics of the PM2.5 pollution evolution of 44 cities in the Beijing-Tianjin-Hebei Region and its surrounding areas were analyzed. The contribution of simultaneous meteorology, coordinated emission reduction, and cross-regional transmission to PM2.5 concentration and chemical component changes were quantified, respectively, with the aim to provide scientific reference for regional air quality joint prevention and control under adverse meteorological conditions. The results showed that the mean value of PM2.5 concentration of 44 cities in 2022 was the lowest(46 μg·m-3) without heavy pollution in the same period of the lunar calendar since 2015, whereas the proportion of days with good air quality was the highest(83.3%). PM2.5 pollution was more serious in the southern region than that in the northern region, and the high values were mainly concentrated along the Taihang Mountains and Yanshan transmission channel cities. In 2016, under the unregulated emission of fireworks in the Spring Festival, the proportion of unpolluted days was 93.5%, which means that the strong atmospheric diffusion ability was crucial to improve air quality. In 2022, the static weather index(SWI) increased by 2.1 compared with that in 2021, indicating unfavorable atmospheric diffusion capacity. The average and peak values of PM2.5 decreased by 14 μg·m-3 and 76 μg·m-3, respectively. The reduction in PM2.5 concentration in Beijing owing to emission reduction measures increased by 96% compared with that before one month. Under the adverse atmospheric background in the Shanxi-Shandong-Henan Region, which contributed to the increase in PM2.5 concentration, the peak value of PM2.5 concentration decreased by 87 μg·m-3, indicating that the peak clipping effect of regional collaborative pollution emission reduction was significant. From 2019 to 2022, the concentration of PM2.5 chemical components decreased yearly with narrowed spatial differences, and the high value was concentrated in the central and southern regions. The descending order of PM2.5 secondary component concentration decrease was as follows:organic matter(21.9%)>sulfate(20%)>ammonium salt(16.7%)>nitrate(9.7%). The proportion of nitrate in PM2.5 increased yearly to 30.1%, indicating that the contribution of traffic pollution was relatively prominent. In 2022, the SNA concentration in the Shanxi-Shandong-Henan Region increased. Pollution from external sources accounted for the main contribution in the Beijing-Tianjin-Hebei Region(>50%). Liaoning Province contributed significantly to the PM2.5 concentration in cities along the Bohai(>10%), and nitrate and sulfate were easy to transport over long distances. It is necessary to strengthen the coordinated control of precursors of secondary chemical components SO2, NOx, and NH3.

Effect of Co-Doping on the Photoelectric Properties of the Novel Two-Dimensional Material Borophene

Borophene is a novel two-dimensional material with abundant crystal structure and photoelectric properties. We focus on the effect of co-doping on the electronic structure and optical properties of borophene using the first-principles method. The results show that the structure of Al and Ga co-doped borophene is obviously distorted because Al and Ga atoms have formed bonds with a bond length of 2.378 Å, and the two B atoms that bond together with Al and Ga are no longer formed bonds. However, it is also a two-dimensional planar structure after co-doping. After co-doping, the band gap width of the borophene system is narrowed from 1.409 eV to 1.376 eV, and the band gap is narrowed by 0.033 eV. Mulliken population analysis shows an obvious charge transfer between Al-B and Ga-B atoms in the co-doped borophene. The calculation of optical properties shows that the static dielectric constant ε1 (0) increases from 5.08 to 7.01, and ε2 (ω) is larger than that of the undoped sample in the low-energy range. Thus, the co-doping of Al and Ga can enhance the electromagnetic energy storage capacity and the visible light absorption ability. Although the reflectance of borophene is reduced by co-doping (the peak of the reflectivity can be decreased from 71% to 61% at E = 2.94 eV), it still presents metallic reflection characteristics. The static refractive index n0 can be increased from 2.25 to 2.65 by co-doping. The extinction coefficient shows strong band edge absorption at the low-energy range with an absorption edge of 0.85 eV. The light loss is limited to a very narrow energy range of approximately 7.30 eV, which indicates that borophene co-doped with Al and Ga can also be used as a light storage material. The optical conductivity reaches its maximum at E = 1.78 eV and 2.52 eV, which correspond to the light irradiation with a wavelength of 698 nm (red light) and 492 nm (cyan light), respectively. The results show that the Al-Ga co-doped borophene is sensitive to cyan light and red light, so it can be used to make photosensitive devices. The results can hopefully fill the gap in the application of borophene in semiconductor photoelectric devices and provide a theoretical basis for its application.

Static and dynamic fuzzy assessment methods for the collapse risk of mountain tunnel construction

The static risk assessment method has difficulty tracking variations of the risk level, which is not conducive to the dynamic control of construction. Tunnel collapse during the construction of mountain tunnels has a dynamic evolution law and contains great risk of harm, and the corresponding dynamic risk assessment is extremely important. This study proposes a static and dynamic fuzzy uncertainty assessment method for the collapse risk of mountain tunnels. First, 150 tunnel collapse accidents were investigated and analysed, and the static and dynamic risk assessment index system of mountain tunnel construction collapse was established. Second, the DEMATEL method is processed by applying fuzzy logic, the subjective weight of each index is calculated, and the interaction between the indexes is analysed. Finally, the traditional VIKOR method is improved upon, and the weight of each assessment index is coupled and analysed. A static and dynamic uncertainty assessment model of the construction collapse risk of multiple construction sections is constructed. This method has been successfully applied to the risk assessment of tunnel collapse, and the assessment results are consistent with the actual construction situation. This study provides a new method for the static and dynamic assessment of mountain tunnel collapse risk.

Influence of Te replacement by Bi in In10Se70Te20-xBix films and its structural, optical, morphological, surface wettability and thermal behaviors for optoelectronic applications

The current investigation is based on Bi doping into In–Se–Te alloy and its impact on the surface morphology, structure, and optical behaviors. The transition from In10Se70Te20 to In10Se70Bi20 composition modified its structural phases as observed from X-ray diffraction study. The crystallite size increased from 9.55 nm to 14.04 nm. The lattice strain decreased from 0.0234 to 0.0106 with Bi content. Raman study infers the microstructural and phase formation in the films. The structure change is associated with change in surface morphology as noticed from field emission scanning electron microscopy images. The composition of In10Se70Te20-xBix (x = 0, 5, 10, 15, 20 at %) films were observed from energy dispersive X-ray analysis. The UV–Vis–NIR data showed the decrease in transmittance from 80 % to 10 % at 2100 nm wavelength with Bi%. The decrease in direct bandgap from 1.64 eV to 1.37 eV was discussed by Davis-Mott model for density of defect states. The increase in Urbach energy from 101 meV to 161 meV is based on the transition from In10Se70Te20 to In10Se70Bi20 composition. The optical parameters like optical density, extinction coefficient and absorption coefficient were increased with Bi addition. The calculated static linear refractive index by different model at different Bi% satisfies Moss's relation. The enhanced non-linear susceptibility from 2.96 × 10−10 esu to 3.33 × 10−10 esu and non-linear refractive index from 1.58 × 10−7 esu to 1.86 × 10−7 esu with Te replacement by Bi may be suitable for non-linear optical devices. The change in different theoretically calculated physical parameters were found to be in accordance with the experimental data. The surface wettability study showed the transition from hydrophilic to hydrophobic nature with increase in Bi %. The obtained experimental results for the films may be used for various photonic and optoelectronic device applications.

Reinforcement Learning Approach for Adaptive C-V2X Resource Management

The modulation coding scheme (MCS) index is the essential configuration parameter in cellular vehicle-to-everything (C-V2X) communication. As referenced by the 3rd Generation Partnership Project (3GPP), the MCS index will dictate the transport block size (TBS) index, which will affect the size of transport blocks and the number of physical resource blocks. These numbers are crucial in the C-V2X resource management since it is also bound to the transmission power used in the system. To the authors’ knowledge, this particular area of research has not been previously investigated. Ultimately, this research establishes the fundamental principles for future studies seeking to use the MCS adaptability in many contexts. In this work, we proposed the application of the reinforcement learning (RL) algorithm, as we used the Q-learning approach to adaptively change the MCS index according to the current environmental states. The simulation results showed that our proposed RL approach outperformed the static MCS index and was able to attain stability in a short number of events.

Nonlinear optical characteristics of chemical bath-deposited pure and Cu-doped SnO2 thin films: A comparative evaluation

A chemical bath deposition method is used to grow SnO2 thin films doped with copper (0, 1, 2, and 3 wt) on glass substrates that exhibit linear and nonlinear optical properties. XRD analysis of the films verified their polycrystalline phases oriented strongly of the c-axis along the preferred (110) direction depending on the doping concentration and substrate temperature. SEM images of pure SnO2 film showed the formation of granular cubic structures. Conversely, the Cu-doped films displayed the existence of spherical granules with porosity. The transmittance spectra of the films for UV–visible light indicated large values for pure films, and that the transmittance decreased with greater doping levels. As a result of copper ions in the nanostructures, it was found that the transmittance decreased as doping levels increased. Pure SnO2 has an optical band gap of 3.63 eV; it decreases with increasing Cu doping concentrations. Wemple-Di Domenico (WDD) model for single oscillator energy was used to estimate each oscillator's optical refractive index, while the static refractive index and dispersion energy were also determined. In addition, the film's WDD parameters and nonlinear refractive index were in the range of 320–1200 nm, and the wavelength was determined. During the doping concentration increase, the nonlinear refractive index of the films increased primarily because the linear refractive index of the films at 520 nm increased. This nonlinearity of the film may arise because of the thermal effect, saturated atomic absorption, and electrostriction. For pure SnO2, third-order nonlinear susceptibility (2.77 × 10-12m2/V2) is caused by thermal effects, and for doped samples, it is caused by photorefractive effects.

TCD assessment in fulminant hepatic failure: Improvements in cerebral autoregulation after liver transplantation

Introduction and ObjectivesAcute liver failure, also known as fulminant hepatic failure (FHF), includes a spectrum of clinical entities characterized by acute liver injury, severe hepatocellular dysfunction and hepatic encephalopathy. The objective of this study was to assess cerebral autoregulation (CA) in 25 patients (19 female) with FHF and to follow up with seventeen of these patients before and after liver transplantation. Patients and MethodsThe mean age was 33.8 years (range 14–56, SD 13.1 years). Cerebral hemodynamics was assessed by transcranial Doppler (TCD) bilateral recordings of cerebral blood velocity (CBv) in the middle cerebral arteries (MCA). ResultsCA was assessed based on the static CA index (SCAI), reflecting the effects of a 20–30 mmHg increase in mean arterial blood pressure on CBv induced with norepinephrine infusion. SCAI was estimated at four time points: pretransplant and on the 1st, 2nd and 3rd posttransplant days, showing a significant difference between pre- and posttransplant SCAI (p = 0.005). SCAI peaked on the third posttransplant day (p = 0.006). Categorical analysis of SCAI showed that for most patients, CA was reestablished on the second day posttransplant (SCAI > 0.6). ConclusionsThese results suggest that CA impairment pretransplant and on the 1st day posttransplant was re-established at 48–72 h after transplantation. These findings can help to improve the management of this patient group during these specific phases, thereby avoiding neurological complications, such as brain swelling and intracranial hypertension.

Inversely engineered biomimetic flexible network scaffolds for soft tissue regeneration.

Graft-host mechanical mismatch has been a longstanding issue in clinical applications of synthetic scaffolds for soft tissue regeneration. Although numerous efforts have been devoted to resolve this grand challenge, the regenerative performance of existing synthetic scaffolds remains limited by slow tissue growth (comparing to autograft) and mechanical failures. We demonstrate a class of rationally designed flexible network scaffolds that can precisely replicate nonlinear mechanical responses of soft tissues and enhance tissue regeneration via reduced graft-host mechanical mismatch. Such flexible network scaffold includes a tubular network frame containing inversely engineered curved microstructures to produce desired mechanical properties, with an electrospun ultrathin film wrapped around the network to offer a proper microenvironment for cell growth. Using rat models with sciatic nerve defects or Achilles tendon injuries, our network scaffolds show regenerative performances evidently superior to that of clinically approved electrospun conduit scaffolds and achieve similar outcomes to autologous nerve transplantation in prevention of target organ atrophy and recovery of static sciatic index.

A Comparative Analysis of the Interaction between Urban-Rural Construction Land Transition and Population Flow: Dominant and Recessive Perspectives

Population flow caused by rapid urbanization has driven the urban-rural construction land transition. A systematic recognition of their interaction is essential for achieving coordinated and sustainable urban-rural development. We chose Hangzhou, one of the most urbanized cities in China, as the study area to analyze this interaction from the perspectives of dominant morphology and recessive morphology during the period of 2010 to 2020. From the perspective of dominant morphology, a structured analysis method is applied to assess the variation in the internal components. A dynamic land utilization efficiency index is proposed and combined with an original static land utilization efficiency index to comprehensively portray a complete periodicity of urban-rural construction land transition and population flow from the perspective of recessive morphology. Results demonstrate that the path dependence of rural industrialization leads to a seemingly stagnant urban-rural construction land transition in Hangzhou. Meanwhile, the rapid increase in the demographic urbanization rate has been supported by the massive inflow of external migrants. Based on the more stringent dynamic land utilization efficiency index and the more comprehensive combination of static and dynamic indices, the moderate expansion of urban construction land increases the proportion of township-level units of the intensive land utilization pattern while, instead of population loss, the general non-intensive land utilization pattern in rural areas has been driven by the overexpansion of rural residential land.

Tuning in linear and nonlinear optical parameters by interfacial mixing of Sb/Ag2Se bilayer thin films under annealing at different temperatures for optoelectronic applications

Semiconducting materials have found enormous interest due to their immense applicability in various optoelectronics fields. In the current report, Sb/Ag2Se bilayer thin film was prepared through thermal evaporation techniques. The thickness of the thin film was 636 nm, where Sb layer of 20 nm was deposited over 616 nm layer of Ag2Se. Bilayer film was annealed at various temperatures for 2hr. The structural study of the material shows the presence of Ag2Se orthorhombic phase. The crystallinity of the material gradually increased with the annealing process. The surface morphology of the material reveals the enhancement in the porosity of the material after annealing. Transmission spectra show a decreased pattern after the annealing process. The optical study showed a red shift in absorption edge and reduced optical bandgap. This may be for the increase in the width of the localised states. Other linear parameters such as skin depth, extinction coefficient and optical density were also estimated from the observed data. The high-frequency dielectric constant and static refractive index increased with annealing temperature, satisfying the Moss rule. 1st and 3rd order non-linear susceptibilities were increased from 0.587 esu to 0.633 esu and 2.02 × 10−11 esu to 2.02 × 10−11 esu, respectively. The surface wettability study of the material shows a transition from hydrophobic to hydrophilic nature. Thiese properties made the sample possible application for self -cleaning material for solar panels or other devices. The observed optical properties of the material prove its applicability to other optoelectronic devices.