Constant Intensity Research Articles

Change in the potential snowfall phenology: past, present, and future in the Chinese Tianshan mountainous region, Central Asia

Abstract. The acceleration of climate warming has led to a faster solid–liquid water cycle and a decrease in solid water storage in cold regions of the Earth. Although snowfall is the most critical input for the cryosphere, the phenology of snowfall, or potential snowfall phenology (PSP), has not been thoroughly studied, and there is a lack of indicators for PSP. For this reason, we have proposed three innovative indicators, namely, the start of potential snowfall season (SPSS), the end of potential snowfall season (EPSS), and the length of potential snowfall season (LPSS), to characterize the PSP. We then explored the spatial–temporal variation in all three PSP indicators in the past, present, and future across the Chinese Tianshan mountainous region (CTMR) based on the observed daily air temperature from 26 meteorological stations during 1961–2017/2020 combined with data from 14 models from CMIP6 (Phase 6 of the Coupled Model Intercomparison Project) under four different scenarios (SSP126, SSP245, SSP370, and SSP585, where SSP represents Shared Socioeconomic Pathway) during 2021–2100. The study showed that the SPSS, EPSS, and LPSS indicators could accurately describe the PSP characteristics across the study area. In the past and present, the potential snowfall season started on 2 November, ended on 18 March, and lasted for about 4.5 months across the CTMR on average. During 1961–2017/2020, the rate of advancing the EPSS (−1.6 d per decade) was faster than that of postponing the SPSS (1.2 d per decade). It was also found that there was a significant delay in the starting time (2–13 d) and advancement in the ending time (1–13 d), respectively, resulting in a reduction of 3–26 d for the LPSS. The potential snowfall season started earlier, ended later, and lasted longer in the north and center compared with the south. Similarly, the SPSS, EPSS, and LPSS indicators are also expected to vary under the four emission scenarios during 2021–2100. Under the highest emission scenario, SSP585, the starting time is expected to be postponed by up to 41 d, while the ending time is expected to be advanced by up to 23 d across the study area. This change is expected to reduce the length of the potential snowfall season by up to 61 d (about 2 months), and the length of the potential snowfall season will only last 2.5 months in the 2100s under the SSP585 scenario. The length of the potential snowfall season in the west and southwest of the CTMR will be compressed by more days due to a more delayed starting time and an advanced ending time under all four scenarios. This suggests that, with constant snowfall intensity, annual total snowfall may decrease, including the amount and frequency, leading to a reduction in snow cover or mass, which will ultimately contribute to more rapid warming through the lower reflectivity to solar radiation. This research provides new insights into capturing the potential snowfall phenology in the alpine region and can be easily extended to other snow-dominated areas worldwide. It can also help inform snowfall monitoring and early warning for solid water resources.

Effect of Photoperiod and White LED on Biomass Growth and Protein Production by Spirulina.

The constant increase in demand for food, valued bio-based compounds and energy demand has prompted the development of innovative and sustainable resources. New technologies and strategies must be implemented to boost microalgae biomass production, such as using different photoperiods along with (LED) light-emitting diodes to stimulate biomass production and boost profits. This work investigates the cultivation of blue-green microalgae (Spirulina) in a closed lab condition. The current study aims to boost Spirulina biomass production by creating ideal growth conditions using different photoperiods (12:12; 10:14; 14:10) light/dark with a constant light intensity of 2000lx from White LED lights. The obtained optical density and protein content was highest for photoperiod 14L: 10D and values were 0.280 OD, with a protein content of 23.44g/100g, respectively. This study is a crucial first step in identifying the best photoperiod conditions to help S. platensis produce more biomass. The study results showed that increasing photoperiod for S. platensis farming can improve the quality and amount of biomass generated in those cultures without negatively affecting growth.

Light strands: exploring flat-field modes in optofluidic fibers for tracking single nano-objects

Structured light has enabled access to new physics and applications, and has particular potential in nanoscience. Here, we present a concept for creating light fields with constant intensity along all three spatial directions—a light strand—within externally accessible liquid-filled nanochannels integrated into optical fiber cores. We demonstrate all relevant properties of this mode, as well as a universally valid condition for obtaining flat fields and experimental evidence from nanoparticle tracking experiments. This concept can be adapted to other waveguides and could be valuable for characterizing rapidly diffusing nanoparticles in life science, analyzing nanoscale chemical reactions, investigating nanorheological phenomena, and understanding fundamental light–matter interactions.

Hemodynamic responses to low-level transcutaneous auricular nerve stimulation in young volunteers.

The aim of this study was to characterize cardiovascular autonomic responses during two constant current intensities below sensory threshold of transcutaneous auricular nerve stimulation (taNS). On this basis, a protocol for taNS with autonomic modulatory potential could be proposed. We included 26 men and 24 women, mean age 26. Data were collected during three randomly allocated 20-minute right tragus stimulation sessions - a) no-stimulation (sham), b) 90µA (arbitrary), and c) 130µA (near the lowest sensory threshold in majority). Stimulation was 20Hz, rectangular pulse width of 2ms, duty cycle 2-second on/off. To assess autonomic responses, we continuously recorded ECG, non-invasive arterial blood pressure (BP) and thoracic impedance cardiography data. Ten-minute data were compared. Fast Fourier transform of RR intervals was performed on 10-minute recordings as well. Low frequency and high frequency power spectra were calculated. Friedman test or one-way ANOVA for repeated measurements and Mann-Whitney or Wilcoxon's signed-rank test, or t-test were carried out. P<0.05 was considered significant. At 130µA stimulation, cardiac output significantly decreased (p<0.05), driven by significant heart rate drop in women, and stroke volume and contractility drop in men, pointing to a gender-related autonomic responses. We observed no significant changes in BP, or variability parameters. Significantly higher body size and BP were found in men, as expected. It seems that tested taNS protocol has a potential for cardiac autonomic modulation in majority of young healthy men as well as women. Further studies are however needed to prove the therapeutic potential of this stimulation protocol in different patient groups.

Determination of Antithyroid Drug Propylthiouracil with Ru (III) in Pharmaceutical Formulations and its Characterization

Background: Background: Sulfur serves as a versatile element and an essential constituent of pharmaceutical industries, natural compounds, proteins, and biological systems. One of the fundamental constituents of sulfur is thiouracil, which forms several derivatives, including 6- methylthiouracil, 6-methyl-2-thiouracil, and 6-propylthiouracil. These derivatives act as effective chelating agents and can form complexes with metal ions. : Compared with other metals, ruthenium possesses unique chemical properties that make it an ideal therapeutic agent. Therefore, this study reports on the propylthiouracil: Ru(III) complex, considering these essential facts. Methods: An equimolar amount of ruthenium trichloride 3.34 x 10-5 M was added to various aliquots ranging from 0.4 mL to 8.8 mL of 3.26 x 10−5 M propylthiouracil. The volume was adjusted to 10 mL with double distilled water. After letting the solution stand for 10 min, we recorded the absorbance of different sets at λmax 376 nm. The Beer-Lambert's law graph demonstrated linearity in the concentration range of 3.18 x101 μgmL-1 to 7.96 x102 μgmL-1, with a linear regression equation of Y = 0.0354 + 0.1109 X. We determined the effective molar absorptivity (ε) to be 6.609 x 102 Lmole-1 cm-1, and the relative standard deviation (RSD %) was ± 0.34%. Results: At room temperature, a yellow-colored complex of propylthiouracil: Ru(III) was formed within 10 min, with a λmax of 376 nm and constant color intensity for 24 h. We confirmed and characterized the formed complex using FTIR, ESR, 1HNMR, thermal analysis, magnetic susceptibility, and powder X-ray. Conclusion: This approach is notable for its precision, accuracy, rapidity, cost-effectiveness, and applicability in tablet form. The novel propylthiouracil: Ru(III) complex offers several advantages, including stability, low absorbance, and no interference with water-soluble ions, eliminating the need for an organic solvent to extract the reaction product. Therefore, this approach could be recommended for quality control in the pharmaceutical industry.

Chlorophyll fluorescence parameter as a predictor of tomato growth and yield under CO2 enrichment in protective cultivation

Greenhouse crops production has been improved by CO2 enrichment commercially. The impact of a threshold level of elevated CO2 (e[CO2]) on the effective quantum yield of photosystem II (ФPSII, chlorophyll fluorescence parameter), which is linked to crop yield, crop growth and fruit quality, is still uncertain. Many previous studies cultivated C3 crops under 550–700 µmol·mol-1, not beyond this range. Hence, tomato plants were grown under ambient CO2 (a[CO2], 500 µmol·mol-1) and e[CO2] (700, 850, and 1000 µmol·mol-1): named as EC700, EC850, and EC1000, respectively, under uniform environmental conditions for two growing seasons to investigate the response of ФPSII along with four photosynthetically active radiation intensities and plant growth to continuous CO2 concentration [CO2]. Under four constant PAR intensities during autumn-winter 2020 and spring-summer 2021, the order of mean ФPSII values under e[CO2] were explored as EC700 > EC1000 > EC850 > a[CO2] and EC700 > EC850 > EC1000 > a[CO2], respectively. The optimum total fruit yield was stimulated under EC700 by 74.04% and 55.86% during autumn-winter 2020 and spring-summer 2021, respectively, as compared to a[CO2]. The results showed that water use efficiency related to yield (WUEy) were enhanced by reducing the stomatal conductance under e[CO2] as compared to a[CO2]. Optimum WUEy was enhanced by 55.91–210.87% under EC700 compared to a[CO2]. The principal component analysis showed strong correlation of ФPSII with plant height, yield and water use efficiency in autumn-winter 2020 and spring-summer 2021, LAI in spring-summer 2021, weak correlation with stem diamter in autumn-winter 2020 and spring-summer 2021, indicated the strong effect of ФPSII on plant growth and yield under e[CO2]. The EC1000 in autumn-winter 2020 and EC700 in spring-summer 2021 were found more influential by the analytic hierarchy process to get optimum crop production, no significant difference between the ranking scores of EC1000 and EC700 during autumn-winter 2020 was found. Thus, the overall optimum impact of e[CO2] on tomato growth was explored under EC700. The findings of this study are beneficial to greenhouses crops production commercially and could be used as references for validating the climate change impact modelling.

Self-biased and biased photo-sensitivity of Tin Mono-Selenide (SnSe) photonic crystal Photodetector under poly/monochromatic light

Recently, transition metal chalcogenides were found to be the most promising candidates for photosensor- and photodetector-based applications. This study reports the photodetection and response properties of tin selenide (SnSe) crystals grown by the direct vapour transport (DVT) technique. The basic properties of SnSe have been reported in a previous article. Photodetection properties are investigated using polychromatic or monochromatic light of varying intensities and bias voltages. Results depict that detectors work congenially under monochromatic sources of light. It is observed that responsivity (Rλ) is higher for red, while detectivity and sensitivity are observed to be maximum for blue light under the self-biased (no bias) condition. The results observed under varying intensity (spot size) in the absence of biassing suggest that as intensity rises, all the parameters of the photodetector are also rising, while at constant intensity (30 mW/cm2), by varying the bias voltage, the detectivity of red light is decreasing due to an increment in dark current. Photodetectors are more efficient at converting optical signals to electrical signals, and their sensitivity is colour-dependent. Mainly, it is observed that monochromatic light shows high sensitivity to low bias voltages, while polychromatic light shows high sensitivity to high voltages. Observed results point to the detection of both monochromatic and polychromatic light by the fabricated detector, which can be applied to SnSe-based devices. A device can be used to fabricate colour and intensity detection.

0308 Impact of Customized Lighting on Sleep in Hospitalized Patients

Abstract Introduction Inpatient sleep may be disrupted for myriad reasons, including lighting exposure that is typically fixed at constant intensity and spectra. In this study we employed customized lighting that promotes circadian entrainment by exposing patients to blue-augmented lighting during the morning and blue-suppressed lighting evening to improve sleep timing and duration. Methods Two Mount Sinai hospital rooms (with 2 beds each) were outfitted with Eight Mattress sensors that use a combination of movement, breathing, heart rate, and temperature variables to estimate wake and sleep vigilance states in 30-second epochs. One room contained customized lighting between 7 am and 11 pm, while the other room contained standard hospital lighting. The current analysis includes 60 participants (30 in the control room and 30 in the custom lighting room), who were matched for time-of-year hospital admission date. We first analyzed the probability of sleep during any given 30-second epoch across each subject’s admission and compared the distributions of sleep probability across the 24-hour cycle for all subjects in the lighting vs control conditions. We additionally evaluated total nocturnal sleep duration(11 PM – 7 AM) by 1) summating all sleep epochs on nights containing at least 50% valid data and 2) normalizing all measured sleep epochs to all valid sleep/wake outputs (excluding indeterminate epochs). Results The distribution of sleep probability was significantly different in the lighting vs control condition (p &amp;lt; 0.001) with most apparent diversion of the distributions between 9 pm and 9 am. The average raw nocturnal sleep duration was significantly higher in lighting condition (270.0 ± 23 minutes vs 201 ± 23 min in control, p = 0.037), as was the average minutes of sleep per hour of valid recording (36.9 ± 15 minutes vs 28.4 ± 13 in control, p = 0.022). There were no significant differences in the number of nocturnal wake or indeterminate epochs between conditions. Conclusion Custom lighting appears to promote sleep in hospitalized patients, but the interpretation is tempered by absence of full validation of the mattress sensor against polysomnography. Future work will evaluate differences in sleep timing and continuity between conditions. Support (if any) McClung Foundation, R01 AG066870

Physiological and cognitive responses to hyperoxic exercise in full water submersion

ABSTRACT The positive effects of combined hyperoxia and physical exercise on physiological parameters and cognitive functioning are established for normobaric laboratory contexts. Still, increased practicability exists in hyperbaric settings like underwater activities and SCUBA diving, where environmental and sport-specific factors might moderate effects. Improved cognition, reduced ventilation (V̇E), and lower blood lactate concentrations [Lac-] are highly relevant, especially during high-stress and rescue scenarios. Fifteen participants performed 3 × 8 min of continuous underwater fin-swimming at 25 % (low), 45 % (moderate), and 75 % (vigorous) heart rate reserve (HRR) in each test. Three separate test days differed solely by the inspiratory oxygen partial pressure (PIO2: 29 kPa, 56 kPa, and 140 kPa). V̇E was measured continuously, whereas breathing gas analysis, blood sampling, and Eriksen Flanker tasks for inhibitory control (100 stimuli) were performed post-exercise. Two-way ANOVAs with repeated measures on the factors PIO2 and exercise intensity analyzed physiological outcome variables and reactions times (RT) and accuracy (ACC) of inhibitory control. V̇E was significantly reduced for 140 kPa during moderate and vigorous and for 56 kPa during vigorous compared to 29 kPa. 56 kPa and 140 kPa showed no differences. [Lac-], post-exercise V̇CO2, and velocity were unaffected by PIO2. Faster RTs but lower ACC of inhibitory control were observed following exercise at 75 % HRR compared to rest, 25 %, and 45 % HRR, while PIO2 produced no effects. Underwater performance in hyperoxia presents reduced V̇E, possible by dampened chemoreceptor sensitivity, and effects on cognition that differ from laboratory results and emphasise the moderating role of sport-specific factors.

Thermoelastic interactions in a rotational medium having variable thermal conductivity and diffusivity with gravitational effect

ABSTRACT This research work is related with the investigation of thermodynamical interactions for a rotational thermodiffusive medium including gravitational effect. To differentiate it from existing works, thermal conductivity and mass diffusivity are considered as variables. The governing equations are formulated under Green–Lindsay (G-L) theory by using Kirchhoff's transformation. Thermal and chemical shocks of constant intensity are imposed on the boundary surface. By using normal mode technique, solutions for the variables considered such as displacement, stress, temperature and chemical potential are achieved. Numerical results are computed for copper material. The impacts of variable thermal conductivity, variable diffusivity, rotation and gravity on different physical fields in the medium are depicted through various figures.

LED Illumination Modules Enable Automated Photoautotrophic Cultivation of Microalgae in Parallel Milliliter-Scale Stirred-Tank Bioreactors

Scalable lab-scale photobioreactors are needed for the exploration of new and improved photoautotrophic bioprocesses. Microbioreactor systems in which parallel bioreactors operate automatically are frequently employed to increase the speed of strain selection as well as the bioprocess-based exploration of heterotrophic fermentation processes. To enable the photoautotrophic operation of a commercially available parallel microbioreactor system with 48 stirred-tank bioreactors, LED illumination modules were designed to allow for individual light supply (400–700 nm) for each of the parallel bioreactors automated by a liquid handling station that performs both individual pH control and OD750 detection. The illumination modules enable dynamic variation of the incident light intensities of up to 1800 µmol m−2 s−1. Automated liquid level detection and volume control of each individual mL-scale gassed photobioreactor has to be established to compensate for evaporation because of the long process times of several days up to weeks. Photoautotrophic batch processes with Microchloropsis salina that employ either varying constant incident light intensities or day and night dynamics resulted in a standard deviation of OD750 of up to a maximum of 10%, with the exception of high-photoinhibiting incident light intensities. The established photoautotrophic microbioreactor system enables the automated investigation of microalgae processes in up to 48 parallel stirred photobioreactors and is thus a new tool that enables efficient characterization and development of photoautotrophic processes with microalgae.

Stability of the RC Column under Horizontal Impacts

Approaches to assessment of stability of reinforced concrete columns in case of horizontal emergency impact have been investigated. For this purpose, finite-element modeling of the system in spatial formulation, calculation according to the deformed scheme in the scope of nonlinear static analysis and dynamic transient process have been implemented. When constructing the model, the hexahedral elements were used, working in accordance with the Drucker-Prager model for concrete, and the rebars deformed according to the Prandtl model were used to modelling the reinforcement.The impact action was considered as a short-term pulse of constant intensity. Dependence diagrams for critical force on various scenarios of emergency impacts on the column have been obtained. Results of researches can be used for an estimation of resistance to the progressive collapse of reinforced concrete structures at their variants design and optimization.

Single-bubble sonoluminescence of aqueous suspensions of ZnS or Tb(acac)3·H2O nanoparticles

Aqueous suspensions of nanoparticles (below 50 nm in size) of ZnS or Tb(acac)3·H2O crystals were prepared by dispersion under multibubble sonolysis. Single-bubble sonoluminescence (SL) of these colloidal suspensions in an ultrasonic standing wave was found. For a ZnS suspension, the SL spectrum of a bubble moving at acoustic pressure pa = 1.29 bar, recorded with 12 nm resolution, exhibited a ZnS band with a maximum at 470 nm against the background of a wide continuum of bubble luminescence (200–700 nm). At a resolution of 1.2 nm, numerous lines of atomic (Zn, S) and ionic (S+, S2+, S3+) emitters were present in the 270–670 nm range. For a Tb(acac)3 suspension at 12 nm resolution, Tb3+ quasilines were detected at 488, 544, 585, and 618 nm (5D4 – 7Fj transitions, j = 6,5,4,3). At 1.2 nm resolution, no terbium atomic lines were found. The ZnS band and Tb3+ quasilines were present, although with a lower intensity (at a constant continuum intensity), in the SL spectra of suspensions for a stationary (pa = 1.07 bar) bubble. The atomic emitter lines for a stationary bubble were absent in the spectra of both suspensions. The ZnS band and Tb3+ quasilines in the SL spectra were similar to those in the photoluminescence (PL) spectra. However, the spectrum of a moving bubble in a Tb(acac)3 suspension differed from the PL spectrum in the relative intensities of the quasilines for some transitions. It was concluded that a non-equilibrium plasma was ignited in a stationary or moving bubble in suspensions under periodic compression of its gas content. This was the main source of luminescence during sonolysis, which was observed as thermal emission bursts in a plasma with a spectral continuum. In addition, sonophotoluminescence was generated as re-emission of the continuum luminescence partially absorbed by nanoparticles in suspensions; this occurred as flashes of ZnS or Tb3+ characteristic luminescence. Additionally, for a moving bubble, there was luminescence of these emitters associated with the entry of nanoparticles into the bubble and the collisional excitation of emitters in the plasma. In the case of a ZnS suspension, there was luminescence of atomic emitters (Zn, S) that formed upon decomposition and excitation of fragments of the initial emitter (ZnS) in a bubble plasma. The absence of a similar component in the SL spectrum of the Tb(acac)3 suspension may be attributable to low efficiency of the collisional excitation of terbium atoms, which were undoubtedly formed upon decomposition of nanoparticles in a bubble plasma. The emitters and mechanisms of the studied single-bubble sonoluminescence in colloidal suspensions were compared with those for the previously considered (J. Luminescence. 252 (2022) 119389) multibubble sonotriboluminescence in non-colloidal suspensions of ZnS or Tb(acac)3·H2O crystals.

Fast Error Calibration for Three-Axis SQUID Magnetometers Based on Full-Space Rotational and Frequency-Controllable Magnetic Field

In order to overcome the limitations of the traditional error calibration method for three-axis superconducting quantum interference device (SQUID) magnetometers, this article presents a fast error calibration method for three-axis SQUID magnetometers. In the proposed method, a full-space rotational and frequency-controllable magnetic field with constant total field intensity can be generated by a triaxial Helmholtz coil. Meanwhile, the nonorthogonal error, zero offset error, and proportional coefficient error of the three-axis SQUID magnetometers, which measure the relative value rather than the absolute value, can be accurately solved by an error modeling and ellipsoid fitting theory. Compared with the traditional scalar calibration method, this method replaces the rotation of Dewar and three-axis SQUID magnetometers with a rotating magnetic field, thus avoiding the interference and influence of motion. Compared with the traditional vector calibration method, this method does not need to ensure the alignment between the three-axis SQUID magnetometers and triaxial Helmholtz coil. Moreover, the interference of low-frequency magnetic field can be suppressed by shortening the period of rotating magnetic field. Simulation and experiments prove the effectiveness of this method. After calibration by the proposed method, the root-mean-square error is reduced to 0.414 from 138.411 nT in the electromagnetic shielding room. Repetitive and comparative experiments with the traditional method in field also prove the superiority and stability of the proposed method.

Targeted Energy Delivery and Heat-Mass Transfer Processes in Systems with Nano-, Micro-, and Macroelements

Introduction. The production of modern technologies should take into account a comprehensive analysis of energy, biotechnological and thermophysical phenomena. The main processes in food technologies are the processes of heat and mass transfer, which need to be intensified. Aim of the Article. The aim of the work is studying the mechanisms and modeling the kinetics of heat and mass transfer in the microware field in the technologies for complex processing of food raw materials. Materials and Methods. The combination of thermal, hydrodynamic and diffusion driving forces with their coordinated action is able to solve problematic issues of processing raw materials, primarily food. Using the principles of the similarity theory, there is proposed a dimensionless complex – the number of energy action, which reflects the influence of the electromagnetic field. Results. Direct, targeted energy supply to the liquid phase of raw materials makes it possible to obtain a solid phase in the apparatus. These are fundamentally new features for the dehydration process. Boil-off rates at constant electromagnetic field intensity depend only on the solvent type. As a result of processing all experimental points, a criterion equation was obtained, it establishes the dependence of the energy action number on the dimensionless pressure and the dimensionless heat of the phase transition. Discussion and Conclusion. There are developed a new class of heat and mass exchange equipment ‒ electrodynamic apparatuses. The experimental results suggest that the flow from capillaries and nano-capillaries is initiated much faster when organizing the processes of targeted energy delivery with the involvement of pulsed microware field. An important advantage of electrodynamic extractors is the possibility of obtaining polyextracts. Food technologies with targeted energy delivery during evaporating, drying and extracting are resource- and energy-efficient and ensure full preservation of raw material potential.

Time-varying jumps in China crude oil futures market impacted by COVID-19 pandemic

China crude oil futures market launched in 2018 has become the third-largest global crude oil exchange, indicating its important role in global crude oil markets. Understanding the time-varying jumps of the newly RMB denominated crude oil futures market is not only for the benefit of the market participants in risk management and hedging, but also for the reference of policy-makers in formulating regulation policies, market pricing and financializing energy markets. However, the literature on time-varying jumps in China crude oil futures market is quite scarce compared with existed literature. In this regard, we attempt to study time-varying jumping behaviors of China crude oil futures market impacted by discrete random events, and analyze the sensitivity of jump intensity, jump size and its variance to market volatility and historical volatility, applying the constant and time-varying intensity jump models, based on the daily returns of China crude oil futures market from March 26, 2018 to August 31, 2021. Further, we compare the differential jumps of China crude oil futures market impacted by COVID-19 pandemic. The empirical results have shown that significant time-varying jumping behaviors appear in China crude oil futures market and take on discrete jumping form. The jump intensity is persistent and sensitive to historical volatility of the market. Meanwhile, jump intensity and jump size increase suffered by great public health emergency, and negative jump size arises with high probability. However, the variance of jump size is little sensitive to historical volatility of the market. These findings suggest that the time-varying jumps, especially negative jumps, should be considered for decision-makers and market participants associated with China crude oil futures market.

Cortical activity during the wind-up of flexion reflex and pain: a magnetoencephalographic study using time-frequency analysis.

Wind-up is a nociceptive-specific phenomenon in which pain sensations are facilitated, in a frequency-dependent manner, by the repeated application of noxious stimuli of constant intensity, with invariant tactile sensations. Thus, cortical activities during wind-up could be an alteration associated with pain potentiation. We aimed to investigate somatosensory-evoked cortical responses and induced brain oscillations during wind-up by recording magnetoencephalograms. Wind-up was produced by the application of 11 consecutive electrical stimuli to the sural nerve, repeated at a frequency of 1Hz without varying the intensity. The augmentation of flexion reflexes and pain rating scores were measured simultaneously as an index of wind-up. In the time-frequency analyses, the γ-band late event-related synchronization and the β-band event-related desynchronization were observed in the primary somatosensory region and the bilateral operculo-insular region, respectively. Repetitive exposure to the stimuli enhanced these activities, along with an increase in the flexion reflex magnitude. The evoked cortical activity reflected novelty, with no alteration to these repetitive stimuli. Observed oscillations enhanced by repetitive stimulation at a constant intensity could reflect a pain mechanism associated with wind-up.

Performance enhancement of swirl-assisted distributed combustion with hydrogen-enriched methane

Effect of hydrogen addition to methane fuel on the performance of swirl-assisted distributed combustion was studied at 5.72 MW/m3-atm thermal intensity using different hydrogen-enrichment (at 0, 10, 20, and 40%) to methane fuel and CO2 and N2 as the flowfield diluents. High-speed chemiluminescence imaging performed (without spectral filtering) exhibited a gradual increase of chemiluminescence intensity along with gradually narrowing of the flame shape for both swirl and distributed combustion with increase in hydrogen-enrichment from increased reactivity in flame brush. Fluctuations of pressure (p′) and heat release (q′) were signals showed the existence of a peak in swirl combustion indicating the possibility of thermo-acoustic coupling. This peak mostly diminished in distributed combustion. Investigation of fluctuation with the proper orthogonal decomposition exhibited no prominent structures in distributed combustion. Measurement of lean blowoff equivalence ratios (ϕLBO) at different combustion conditions showed extended ϕLBO in distributed combustion indicating wider operational limits in distributed combustion. The NO emission increased in conventional swirl combustion while it consistently decreased in distributed combustion even at increased H2 enrichment to methane fuel. The exhaust CO2 gradually decreased with increase in H2 enrichment for both swirl and distributed reaction zones at constant thermal intensity. Reduced pollutants emission with hydrogen enrichment was also observed with air preheats in the range of 373–573 K to support distributed combustion for gas turbine conditions.

How the Distribution of Photon Delivery Impacts Crops in Indoor Plant Environments: A Review

Indoor plant production allows for increased controllability over plant growth, particularly with the employment of specific lighting regimes. This article reviews research investigating the influence of various light regimes that provide crops with the same light spectrum and daily light integral (DLI), yet with different lighting schedules and intensities. The structure of these light regimes includes changing photoperiod duration and light intensity, cyclic lighting schedules (increased number of light/dark cycles over 24 h, same total illuminated time and intensity), and intermittent and fluctuating lighting (with intervals ranging from 60 s to 60 min). The most common crops investigated were leafy greens, although some fruiting, ornamental, and model crop Arabidopsis are included. Under constant DLI, extending photoperiod and reducing light intensity generally increased the total amount of biomass accumulation and increased light interception. Increases in the number of shortened light/dark cycles contributed to decreased yield, leaf area, and photosynthetic rate, compared to the more standard single light/dark cycle. Intermittent and fluctuating lighting regimes generally reduced biomass accumulation and light interception. These results indicate that the total amount of light delivered to crops is important, but how that light is delivered can influence crop growth. This review will be useful for growers and researchers when designing lighting systems and regimes to produce horticultural crops in indoor plant environment systems.

The NRCS curve number equation derived from an instantaneous unit hydrograph: Some consequences

The NCRS-curve number equation allows calculating the storm runoff from a rainfall event for specific types of land use. It was based on an analysis of direct runoff data using baseflow corrected hydrographs and rainfall. Given this basis, the curve number equation can be derived assuming a constant effective rainfall intensity and a cubic reciprocal function as the instantaneous unit hydrograph. The instantaneous unit hydrograph and the resulting curve number equation are further generalized by adding a lag time. The equation for a curve number related hydrograph is presented, allowing to fit this curve number-based hydrograph to event data. The curve number itself is shown be a function of a catchment response time and the average event rainfall intensity. As the catchment response time is linked to the time of concentration the curve number equation and the storage index can be linked to catchment- and flow type characteristics. First results suggest that including the rainfall intensity duration frequency function in the curve number equation may explain systematic deviations observed when fitting the NCRS curve number equation to measured data.