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The Okmok volcanic eruption in Alaska has recently been discovered and is precisely dated to have occurred in 43 BCE. Some Chinese climate records of 43–33 BCE have been found in historical documents that provide descriptions of observed environmental abnormities that appear to be consistent with the anticipated changes due to volcanic climate forcing. In this paper, we provide a full translation with discussions of the Chinese climate records that may be related to the Okmok eruption. We have converted ancient Chinese calendar dates to modern Gregorian dates and provided the latitudes and longitudes of the geographical locations mentioned in the records. Relevant climate information in similar areas of China in the decades after the 1783 Laki eruption is also briefly summarized for comparison. We believe the detailed information contained in these records will be useful for further research on the climate impact of volcanic eruptions.

The Gaoping Submarine Canyon (GPSC) off southwest Taiwan has been extensively studied due to its unique geology, its role in transferring terrestrial material to the deep sea, and its diverse biological communities. However, there is a lack of understanding of carbon cycling across the sediment–water interface in the canyon. This study aims to fill the gap by utilizing the field data collected between 2014 and 2020 and a linear inverse model (LIM) to reconstruct the benthic food web (i.e., carbon flows through different stocks) in the head of GPSC and the upper Gaoping slope (GS). The biotic and abiotic organic carbon (OC) stocks were significantly higher on the slope than in the canyon, except for the bacteria stock. The sediment oxygen utilization was similar between the two habitats, but the magnitude and distribution of the OC flow in the food web were distinctively different. Despite a significant input flux of ∼ 2020 mg C m−2 d−1 in the canyon, 84 % of the carbon flux exited the system, while 12 % was buried. On the slope, 84 % of the OC input (∼ 109 mg C m−2 d−1) was buried, and only 7 % exited the system. Bacteria processes play a major role in the carbon fluxes within the canyon. In contrast, the food web in the upper slope exhibited stronger interactions among metazoans, indicated by higher fluxes between meiofauna and macrofauna compartments. Network indices based on the LIM outputs showed that the canyon head had higher total system throughput (T..) and total system throughflow (TST), indicating greater energy flowing through the system. In contrast, the slope had a significantly higher Finn cycling index (FCI), average mutual information (AMI), and longer OC turnover time, suggesting a relatively more stable ecosystem with higher energy recycling. Due to sampling limitations, the present study only represents the benthic food web during the “dry” period. By integrating the field data into a food web model, this study provides valuable insight into the fates of OC cycling in an active submarine canyon, focusing on the often overlooked benthic communities. Future studies should include “wet” period sampling to reveal the effects of typhoons and monsoon rainfalls on OC cycling.

With the development of different sensors, such as global navigation satellite system (GNSS), inertial measurement unit (IMU), LiDAR, radar and camera, more localization information is available for autonomous vehicular applications. However, each sensor has its limitations in different circumstances. For example, visual Simultaneous Localization and Mapping (SLAM) easily loses tracking in an open sky area where accurate GNSS measurements can be obtained. Sensors can complement each other by integrated their information in a multi-sensor fusion scheme. In this study, we proposed a visual-SLAM enhanced INS/GNSS localization fusion scheme for a high dynamic environment. Oriented FAST and rotated BRIEF (ORB) SLAM are used to pre-process image sequences from monocular camera, rescaled and refreshed after applying GNSS measurements, and convert to position and velocity information, which can provide updates to the system. The performance of the fusion system was verified through two field tests at different speed ranges (about 30–60 km/s), using a reliable reference system as ground-truth to assess the accuracy of the proposed localization fusion scheme. The results indicated that the proposed system could improve the navigation accuracy compared to INS/GNSS integration scheme and achieve which-lane level or even where-in-lane level.

This study presents a new epistemological analysis of drought chronology through a well-defined methodology for reconstructing past drought series, as well as series of other associated ecological and societal impact variables. Instead of building a grading system based on mixed criteria, this method facilitates transparency in the reconstruction process and enables the statistical examination of all variables when building series. The data for the present study are derived mainly from the REACHES (Reconstructed East Asian Climate Historical Encoded Series) database; however, other archival documentary and index data from independent sources are also applied to understand drought narratives and to cross-check and validate the analysis derived from REACHES. From the time series analysis, six severe drought periods are identified in the Qing dynasty, and then a spatial analysis is performed to demonstrate the spatial distribution of drought and other variables in the six periods, as well as a social network analysis to reveal connections between drought and other ecological and societal variables. Research results clearly illustrate the role of human intervention in influencing the impacts of drought and their societal consequences. Particularly, the correlation between drought and socioeconomic turmoil is not strong; crop failure and famine are important intermediate factors, while ecological factors such as locust and disaster relief measures are all imperative to intervene between crop production and famine. Implications of the study on drought impact are provided, as well as the significance of drought on historical climate reconstruction studies.

The capacity of the terrestrial biosphere to sequester carbon and mitigate climate change is governed by the ability of vegetation to remove emissions of CO2 through photosynthesis. Tropospheric O3, a globally abundant and potent greenhouse gas, is, however, known to damage plants, causing reductions in primary productivity. Despite emission control policies across Europe, background concentrations of tropospheric O3 have risen significantly over the last decades due to hemispheric-scale increases in O3 and its precursors. Therefore, plants are exposed to increasing background concentrations, at levels currently causing chronic damage. Studying the impact of O3 on European vegetation at the regional scale is important for gaining greater understanding of the impact of O3 on the land carbon sink at large spatial scales. In this work we take a regional approach and update the JULES land surface model using new measurements specifically for European vegetation. Given the importance of stomatal conductance in determining the flux of O3 into plants, we implement an alternative stomatal closure parameterisation and account for diurnal variations in O3 concentration in our simulations. We conduct our analysis specifically for the European region to quantify the impact of the interactive effects of tropospheric O3 and CO2 on gross primary productivity (GPP) and land carbon storage across Europe. A factorial set of model experiments showed that tropospheric O3 can suppress terrestrial carbon uptake across Europe over the period 1901 to 2050. By 2050, simulated GPP was reduced by 4 to 9 % due to plant O3 damage and land carbon storage was reduced by 3 to 7 %. The combined physiological effects of elevated future CO2 (acting to reduce stomatal opening) and reductions in O3 concentrations resulted in reduced O3 damage in the future. This alleviation of O3 damage by CO2-induced stomatal closure was around 1 to 2 % for both land carbon and GPP, depending on plant sensitivity to O3. Reduced land carbon storage resulted from diminished soil carbon stocks consistent with the reduction in GPP. Regional variations are identified with larger impacts shown for temperate Europe (GPP reduced by 10 to 20 %) compared to boreal regions (GPP reduced by 2 to 8 %). These results highlight that O3 damage needs to be considered when predicting GPP and land carbon, and that the effects of O3 on plant physiology need to be considered in regional land carbon cycle assessments.

Stomatal conductance (gs) affects the fluxes of carbon, energy and water between the vegetated land surface and the atmosphere. We test an implementation of an optimal stomatal conductance model within the Community Atmosphere Biosphere Land Exchange (CABLE) land surface model (LSM). In common with many LSMs, CABLE does not differentiate between gs model parameters in relation to plant functional type (PFT), but instead only in relation to photosynthetic pathway. We constrained the key model parameter "g1", which represents plant water use strategy, by PFT, based on a global synthesis of stomatal behaviour. As proof of concept, we also demonstrate that the g1 parameter can be estimated using two long-term average (1960–1990) bioclimatic variables: (i) temperature and (ii) an indirect estimate of annual plant water availability. The new stomatal model, in conjunction with PFT parameterisations, resulted in a large reduction in annual fluxes of transpiration (~ 30% compared to the standard CABLE simulations) across evergreen needleleaf, tundra and C4 grass regions. Differences in other regions of the globe were typically small. Model performance against upscaled data products was not degraded, but did not noticeably reduce existing model–data biases. We identified assumptions relating to the coupling of the vegetation to the atmosphere and the parameterisation of the minimum stomatal conductance as areas requiring further investigation in both CABLE and potentially other LSMs. We conclude that optimisation theory can yield a simple and tractable approach to predicting stomatal conductance in LSMs.

This paper focuses on the climate variability in central China since AD 1300, involving: (1) a well-dated, 1.5-year resolution stalagmite δ18O record from Lianhua Cave, central China (2) links of the δ18O record with regional dry–wet conditions, monsoon intensity, and temperature over eastern China (3) correlations among drought events in the Lianhua record, solar irradiation, and ENSO (El Niño–Southern Oscillation) variation. We present a highly precise, 230Th / U-dated, 1.5-year resolution δ18O record of an aragonite stalagmite (LHD1) collected from Lianhua Cave in the Wuling Mountain area of central China. The comparison of the δ18O record with the local instrumental record and historical documents indicates that (1) the stalagmite δ18O record reveals variations in the summer monsoon intensity and dry–wet conditions in the Wuling Mountain area. (2) A stronger East Asian summer monsoon (EASM) enhances the tropical monsoon trough controlled by ITCZ (Intertropical Convergence Zone), which produces higher spring quarter rainfall and isotopically light monsoonal moisture in the central China. (3) The summer quarter/spring quarter rainfall ratio in central China can be a potential indicator of the EASM strength: a lower ratio corresponds to stronger EASM and higher spring rainfall. The ratio changed from 1 after 1950, reflecting that the summer quarter rainfall of the study area became dominant under stronger influence of the Northwestern Pacific High. Eastern China temperatures varied with the solar activity, showing higher temperatures under stronger solar irradiation, which produced stronger summer monsoons. During Maunder, Dalton and 1900 sunspot minima, more severe drought events occurred, indicating a weakening of the summer monsoon when solar activity decreased on decadal timescales. On an interannual timescale, dry conditions in the study area prevailed under El Niño conditions, which is also supported by the spectrum analysis. Hence, our record illustrates the linkage of Asian summer monsoon precipitation to solar irradiation and ENSO: wetter conditions in the study area under stronger summer monsoon during warm periods, and vice versa. During cold periods, the Walker Circulation will shift toward the central Pacific under El Niño conditions, resulting in a further weakening of Asian summer monsoons.

Amino sugars are quantitatively significant constituents of soil and marine sediment, but their sources and turnover in environmental samples remain poorly understood. The stable carbon isotopic composition of amino sugars can provide information on the lifestyles of their source organisms and can be monitored during incubations with labeled substrates to estimate the turnover rates of microbial populations. However, until now, such investigation has been carried out only with soil samples, partly because of the much lower abundance of amino sugars in marine environments. We therefore optimized a procedure for compound-specific isotopic analysis of amino sugars in marine sediment, employing gas chromatography–isotope ratio mass spectrometry. The whole procedure consisted of hydrolysis, neutralization, enrichment, and derivatization of amino sugars. Except for the derivatization step, the protocol introduced negligible isotopic fractionation, and the minimum requirement of amino sugar for isotopic analysis was 20 ng, i.e., equivalent to ~8 ng of amino sugar carbon. Compound-specific stable carbon isotopic analysis of amino sugars obtained from marine sediment extracts indicated that glucosamine and galactosamine were mainly derived from organic detritus, whereas muramic acid showed isotopic imprints from indigenous bacterial activities. The δ13C analysis of amino sugars provides a valuable addition to the biomarker-based characterization of microbial metabolism in the deep marine biosphere, which so far has been lipid oriented and biased towards the detection of archaeal signals.

The vibrational energy relaxation rates of the water bend in chloroform and d-chloroform are calculated by using the Landau-Teller formula with a new potential model developed and parametrized for describing the chloroform-water interaction. The studies have shown that the relaxation has involved both the bend and the C-Cl stretches and that the frequency changes of all of the modes upon deuteration has contributed to the solvent isotope effect.

Data from a MOSFET matrix on two JPL CRRES chips, each behind different amounts of shielding, is presented. Space damage factors are nearly identical to ground test values for MOSFETs. The results from neighboring rows of MOSFETs show similar radiation degradation. The SRD (Space Radiation Dosimeter) is used to measure the total dose accumulated by the JPL chips. A parameter extraction algorithm that does not under estimate threshold voltage shifts is used. Temperature effects are removed from the MOSFET data.

We report a mask-free technique for the local synthesis of ZnO nanowires (NWs) on polysilicon nanobelts and polysilicon NW devices. First, we used localized joule heating to generate a poly(methyl methacrylate) (PMMA) nanotemplate, allowing the rapid and self-aligned ablation of PMMA within a short period of time (ca. 5 μs). Next, we used ion-beam sputtering to prepare an ultrathin Au film and a ZnO seed layer; a subsequent lift-off process left the seed layers selectively within the PMMA nanotemplate. Gold nanoparticles and ZnO NWs were formed selectively in the localized joule heating region. [ABSTRACT FROM AUTHOR]

In this work we study the structural response of silicalite based MFI type zeolite powder to the presence of water and cations commonly found in sea salts including Na+, K+, Ca2+, and Mg2+. MFI zeolite powder was exposed to different solutions (3.8 wt% TDS (total dissolved solids) seawater (SW), or 1 M NaCl, or 0.05 M KCl), and their effects on the structure of the zeolite powder were characterized. The results obtained from ion adsorption testing and synchrotron X-ray powder diffraction showed that the zeolite powder interacted with water, monovalent and divalent cations, and these interactions altered the crystal dimensions of the zeolite. Most exposures to ions and water led to increases in crystal volumes of <0.1%, but exposure to KCl solution was observed to make the biggest contribution to crystal expansion, at 0.59%, particularly in the a- and c-directions as determined by Rietveld refinement. Upon closer inspection of SW exposed silicalite, a rapid exchange of Na+and K+was observed within 1 h, but after 8 h, these monovalent cations were gradually exchanged with divalent ions. Ca2+was especially observed to adsorb into the zeolite at 8 h. N2adsorption and positron annihilation lifetime spectroscopy (PALS) measurements were made on SW exposed zeolites. PALS showed that the silicalite powder has mesopores (2.6 nm) and micropores (1.0 nm), which are both attributed to intercrystalline spaces. The intrinsic intracrystalline zeolite pore size was measured as 0.33 nm. Both N2adsorption and PALS showed that the relative amount of micropores to total pores decreased with seawater exposure which was attributed to ion adsorption and ion exchange. The mesopore size and number increase due to exposure, and although mesopores represent defects in crystalline zeolites, their expansion on exposure to seawater is important for membrane stability and diffusion properties and warrants further investigation. The intrinsic zeolite pore size was smaller in zeolites exposed to seawater (∼0.29 nm), and the changes observed by PALS lead us to conclude that most of the ion activity observed is attributed to the intercrystalline micropores and mesopores. No other changes were observable by Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) due to SW exposure. Results indicate that the interaction between silicalite and the water and ions in SW causes a change in structure and porosity expected to affect diffusion properties of these materials when used as membranes for desalination. [ABSTRACT FROM AUTHOR]

Due to rapid technological innovation and global competitiveness, the selling price of products in hi-tech industries usually declines significantly with time. This study develops a deteriorating inventory model for the product experiencing continuous decrease in unit price. This inventory model, from the perspective of supplier, proposes an efficient replenishment policy for a single-supplier-and-single-buyer supply chain in which the buyer conducts JIT through a realisation of multiple deliveries and the supplier performs one-time production. The objective of this model is, on the basis of the buyer's economic ordering decisions, to maximise the supplier's profit during a finite planning horizon and then to determine the optimal production cycle and product life cycle. A simple heuristic algorithm is developed to derive the optimal solution for the model. Numerical examples and sensitivity analyses confirm the performances of the proposed model and reveal some interesting managerial implications. [ABSTRACT FROM AUTHOR]

This paper demonstrates a proof-of-concept approach for encapsulating the anticancer drug tamoxifen, Fe3O4nanoparticles (NPs) and CdTe quantum dots (QDs) into size-controlled polycaprolactone (PCL) microcapsules utilizing microfluidic emulsification, which combined magnetic targeting, fluorescence imaging and drug controlled release properties into one drug delivery system. Cross-linking the composite PCL microcapsules with poly(vinyl alcohol) (PVA) tailored their size, morphology, optical and magnetic properties and drug release behaviors. The flow conditions of the two immiscible solutions were adjusted in order to successfully generate various sizes of polymer droplets. The result showed superparamagnetic and fluorescent properties, and was used as a controlled drug release vehicle. The composite magnetic and fluorescent PCL microcapsules are potential candidates for a smart drug delivery system. [ABSTRACT FROM AUTHOR]

The amide I vibrational mode, primarily associated with peptide-bond carbonyl stretches, has long been used to probe the structures and dynamics of peptides and proteins by infrared (IR) spectroscopy. A number of ab initio-based amide I vibrational frequency maps have been developed for calculating IR line shapes. In this paper, a new empirical amide I vibrational frequency map is developed. To evaluate its performance, we applied this map to a system of isotope-edited CD3-ζ membrane peptide bundles in aqueous solution. The calculated 2D-IR diagonal line widths vary from residue to residue and show an asymmetric pattern as a function of position in the membrane. The theoretical results are in fair agreement with experiments on the same system. Through analysis of the computed frequency time-correlation functions, it is found that the 2D-IR diagonal widths are dominated by contributions from the inhomogeneous frequency distributions, from which it follows that these widths are a good probe of the extent of local structural fluctuations. Thus, the asymmetric pattern of line widths follows from the asymmetric structure of the bundle in the membrane. [ABSTRACT FROM AUTHOR]

Perovskite-type La−Sr−Co−Fe metal oxides have been demonstrated as sorbents in a high-temperature sorption separation process for production of an oxygen-enriched gas stream for oxycombustion application. This paper reports on characteristics and fixed-bed performance of improved perovskite-type sorbents, Sr−Ca−Co−Fe oxides, in comparison with a reference La−Sr−Co−Fe oxide sorbent for high-temperature production of an oxygen-enriched carbon dioxide stream. The optimum composition of Sr0.5Ca0.5Co0.5Fe0.5O2.47(SCCF) is identified through study of carbonation (oxygen desorption) kinetics of Sr−Ca−Co−Fe oxides with different Ca and Fe concentrations. Carbonation kinetics of SCCF were studied at different temperatures from 700 to 900 °C. Below 750 °C, interaction of SCCF with carbon dioxide results in formation of Sr and Ca carbonates. At higher temperature, SCCF turns to form oxides of the respective metals under a stream of carbon dioxide. The improved sorbent has a faster oxygen desorption kinetic rate and higher oxygen storage capacity than the reference material. Effects of the operation temperature on the fixed-bed desorption/adsorption process for production of an oxygen-enriched carbon dioxide stream were investigated. Optimal temperatures for adsorption and desorption processes are determined to be 700 and 850 °C, respectively. The fixed-bed process can produce an oxygen-enriched stream at an oxygen concentration of 50%. The improved sorbent exhibits a gradually decreased carbonation (oxygen desorption) kinetics in the first few cycles of oxygen sorption and desorption and then stable kinetics in cycles afterward. [ABSTRACT FROM AUTHOR]

This investigation proposes the improved double δ-doped InGaP/InGaAs heterostructure field-effect transistor (HFET) grown by metalorganic chemical vapour deposition. The extrinsic transconductance (gm) and saturation current density (Imax) of the double δ-doped InGaP/InGaAs HFET are superior to those of the previously reported single δ-doped InGaP/InGaAs HFETs. The first n-InAlGaP/GaAs HFET is also investigated because it has a high Schottky barrier, a large high band gap and a large conduction-band discontinuity (ΔEC). Even without indium in the channel of the InAlGaP/GaAs HFET, gm and Imax are as high as 170 mS mm−1 and 410 mA mm−1, respectively. The gm values of these two HFETs remain large even when the gate voltages are positive. Moreover, the breakdown voltages of the two examined HFETs both exceed 40 V. [ABSTRACT FROM AUTHOR]

Clinical reports document that depression as a side effect is more prevalent in hepatic patients given interferon (IFN)-α therapy than in those given lamivudine. The mechanisms, however, are poorly understood. Serotonin transporter (5-HTT), via uptake of serotonin (5-HT) into presynaptic serotoninergic neurons, is an initial action site for antidepressants. Real-time polymerase chain reaction (PCR) was used to quantify 5-HTT mRNA expression in immune cells in order to evaluate whether 5-HTT acted as an indicator of depression. Results showed that the 5-HTT mRNA expression was much higher in T-cell and B-cell lines than that in a monocytic cell line. Treatment with either lamivudine or ribavirin reduced the 5-HTT mRNA expression, protein level and 5-HT uptake in T-cell line. Treatment with IFN-α, however, increased those levels in the same group. A similar effect was observed in peripheral blood mononuclear cells (PBMC). Mimicking clinical use by treating PBMC with a combination of IFN-α and ribavirin increased the 5-HTT mRNA expression level. Our study indicates that these therapeutic drugs regulate 5-HTT expression, which implies that 5-HTT might be a trait marker in IFN-α-induced depression after hepatic therapy. [ABSTRACT FROM AUTHOR]

Zeolite membranes offer great application potentials in membrane separation and/or reaction due to their excellent separation performance and catalytic ability. Up to present, various synthesis methods of zeolite membranes have been developed, including embedded method, in-situ hydrothermal synthesis method, and secondary growth method etc. Compared with the in-situ hydrothermal synthesis method, the secondary growth method possesses a variety of advantages such as easier operation, higher controllability in crystal orientation, microstructure and film thickness, leading to much better reproducibility. This review provides a concise summary and analysis of various synthesis methods reported in the literature. In particular, the secondary growth method was discussed in detail in terms of crystal orientation, defects and crystal grain layers. Some critical issues were also highlighted, which were conducive to the improvement in the synthesis technology of zeolite membranes. [ABSTRACT FROM AUTHOR]

We designed and fabricated a new type of superconducting quantum interference device (SQUID) susceptometers for magnetic imaging of quantum materials. The 2-junction SQUID sensors employ 3D Nb nano-bridges fabricated using electron-beam lithography. The two counter-wound balanced pickup loops of the SQUID enable gradiometric measurement and they are surrounded by a one-turn field coil for susceptibility measurements. The smallest pickup loop of the SQUIDs were 1 μm in diameter and the flux noise was around 1 μФ0/√Hz at 100 Hz. We demonstrate scanning magnetometry, susceptometry and current magnetometry on some test samples using these nano-SQUIDs. [ABSTRACT FROM AUTHOR]

Abstract Influenza is an acute respiratory infection that spreads rapidly and widely in densely populated areas with low vaccination coverage. The trends and drivers of the spatial and temporal dynamics of influenza incidence among residents of mainland China have not been systematically studied. This study comprehensively analyses the dynamics and spatial correlation of influenza using long‐term scale data and spatial panel data. It then identifies the interactive process of socio‐economic and natural elements on the incidence of influenza. The highest prevalence of influenza was found in the 0–4 years age group in mainland China (mean prevalence, 67.56/100,000). In addition, influenza in mainland China shows seasonality, with fall and winter being the periods of high incidence. Between 2014 and 2017, influenza incidence was clustered in Hubei and Anhui provinces, and the spatial clustering was statistically significant (Z value > 1.96, P

A low-power and wideband three-stage 77-81 GHz low-noise amplifier (LNA) using standard 90 nm CMOS technology is reported. The T-match technique is utilised to achieve simultaneously wideband input and output impedance matching, wideband power gain (S21) and a wideband noise figure (NF). The LNA consumes 21.1 mW, achieving S11 better than -10 dB for the frequencies 62.3-82.4 GHz, S22 better than -10 dB for the frequencies 62.8-84.6 GHz, S12 better than -29 dB for the frequencies 72-84 GHz and a group delay variation smaller than ±4 ps for the frequencies 77-81 GHz. In addition, high and flat S21 of 13.1 ± 1.5 dB is achieved for the frequencies 72-84 GHz, which means the corresponding 3 dB bandwidth is 12 GHz. Furthermore, the LNA achieves a minimum NF of 6.2 dB at 78 GHz and a NF of 6.8 ± 0.6 dB for the frequencies 75-82 GHz, one of the best NF results ever reported for a CMOS LNA for 77-81 GHz automotive radar applications. [ABSTRACT FROM AUTHOR]

A low power and low noise figure (NF) 60 GHz low-noise amplifier (LNA) with excellent phase linearity using standard 90 nm CMOS technology is reported. The LNA comprises a common-source (CS) stage followed by a cascode stage and a CS stage. The LNA consumes 14.1 mW, achieving S22 better than - 10 dB for the frequencies 55.1- 59.5 GHz, S22 better than - 10 dB for the frequencies 55.1-59.4 GHz, and group delay variation smaller than ± 13.25 ps for the frequencies 50.4-63 GHz. Additionally, high and flat S21 of 9.9 ± 1.5 dB is achieved for the frequencies 50.4-62.9 GHz, which means the corresponding 3 dB bandwidth is 12.5 GHz. Furthermore, the LNA achieves a minimum NF of 3.88 dB at 55.5 GHz and an NF of 4.73 ± 0.85 dB for the frequencies 50-63.5 GHz, one of the best NF results ever reported for a 60 GHz CMOS LNA. [ABSTRACT FROM AUTHOR]

Zeolite membranes are a new class of membranes with distinct permeation/separation properties. In the past few years, various research groups have reported synthesis of good quality zeolite membranes without meso and macroporous defects. These zeolite membranes are of polycrystalline microstructure, consisting of the zeolitic pores with minimized gaps between the zeolite crystallites. Most of these zeolite membranes exhibit excellent vapor or liquid separation properties for molecules smaller than the zeolitic pores. The differences in the chemical affinities, of the zeolite pore determine the seperation properties of the zeolite membranes.

Self-driving car technology has become increasingly popular in recent years. Traditionally, these cars rely on GNSS and INS, but limitations in urban environments can affect their effectiveness. GNSS technology has developed to address this issue, but it still has limitations in certain environments. LiDAR technology has emerged as a solution to obtain high-precision point cloud maps and SLAM technology is now used to integrate these maps with sensor data, such as cameras, to achieve precise positioning. This enables visual SLAM to be performed in environments where GNSS signals are blocked. In this research, we aim to use SLAM technology to obtain posterior environmental information and match it with prior high-precision point cloud maps. The research will start with hardware configuration, actual measurement and analysis of SLAM algorithms, and 3D point cloud matching methods. Results and benefits will be analysed to compare the advantages and disadvantages of point cloud matching algorithms and applicable hardware.

Abstract Various methods of evaluating a humectant’s moisture retention have unique mechanisms. Hence, for designing advanced or efficient ingredients of cosmetic products, a clear understanding of differences among methods is required. The aim of this study was to analyze the moisture-retention capacity of glycerin, a common ingredient in cosmetic products. Specifically, this study applied gravimetric analysis, transepidermal water loss (TEWL) analysis, and differential scanning calorimetry (DSC) to examine the evaporation of glycerin solutions of different concentrations. The results revealed that the moisture-retention capacity of glycerin increased with the glycerin concentration from 0 to 60 wt%, and glycerin at concentration of 60–70 wt% did not exhibit weight change during the evaporation process. When the glycerin concentration exceeded 70 wt%, moisture sorption occurred in the glycerin solution. Furthermore, the results revealed a deviation between the evaporation rates measured using gravimetric analysis and those measured using TEWL analysis. However, normalizing the results of these analyses yielded the relative evaporation rates to water, which were consistent between these two analyses. DSC thermograms further confirmed the consistent results and identified two hydrated water microstructures (nonfreezable water and free water) in the glycerin solutions, which explained why the measured evaporation rate decreased with the glycerin concentration. These findings can be applied to prove the moisture-retention capacity of a humectant in cosmetic products by different measuring methods.

Vortices are topological defects of type-II superconductors in an external magnetic field. In a similar fashion to a quantum anomalous Hall insulator, quantum anomalous vortices (QAV) spontaneously nucleate due to orbital-and-spin exchange interaction between supercurrent and magnetic impurity moment without an external magnetic field. Here, we used scanning superconducting quantum interference device microscopy (sSQUID) to search for its signatures in iron-chalcogenide superconductor Fe(Se,Te). Under zero magnetic field, we found a stochastic distribution of isolated anomalous vortices and antivortices with flux quanta Φ_{0}. By applying a small local magnetic field under the coil of the nano-SQUID device, we observed hysteretic flipping of the vortices reminiscent of the switching of ferromagnetic domains, suggesting locally broken time-reversal symmetry. We further observed vectorial rotation of a flux line linking a vortex-antivortex pair by manipulating the local field. These unique properties of the anomalous vortices satisfy the defining criteria of QAV. Our observation suggests an emergent quantum phase with spontaneously nucleated vortex-antivortex matter in an iron-based superconductor with nontrivial topological band structure.