Rare finding of primary aortoduodenal fistula on single-photon emission computed tomography/computed tomography of gastrointestinal bleeding: A case report

BACKGROUND Primary aortoduodenal fistula is a rare cause of gastrointestinal(GI)bleeding consisting of abnormal channels between the aorta and GI tract without previous vascular intervention that results in massive intraluminal hemorrhage.CASE SUMMARY A 67-year-old man was hospitalized for coffee ground vomiting,tarry stools,and colic abdominal pain.He was repeatedly admitted for active GI bleeding and hypovolemic shock.Intermittent and spontaneously stopped bleeders were undetectable on multiple GI endoscopy,angiography,computed tomography angiography(CTA),capsule endoscopy,and ^(99)mTc-labeled red blood cell(RBC)scans.The patient received supportive treatment and was discharged without signs of rebleeding.Thereafter,he was re-admitted for bleeder identification.Repeated CTA after a bleed revealed a small aortic aneurysm at the renal level contacting the fourth portion of the duodenum.A ^(99)mTc-labeled RBC singlephoton emission CT(SPECT)/CT scan performed during bleeding symptoms revealed active bleeding at the duodenal level.According to his clinical symptoms(intermittent massive GI bleeding with hypovolemic shock,dizziness,dark red stool,and bloody vomitus)and the abdominal CTA and ^(99)mTc-labeled RBC SPECT/CT results,we suspected a small aneurysm and an aortoduodenal fistula.Subsequent duodenal excision and duodenojejunal anastomosis were performed.A 7-mm saccular aneurysm arising from the anterior wall of the abdominal aorta near the left renal artery was identified.Percutaneous intravascular stenting of the abdominal aorta was performed and his symptoms improved.CONCLUSION Our findings suggest that ^(99)mTc-labeled RBC SPECT/CT scanning can aid the diagnosis of a rare cause of active GI bleeding.

Hepatic clearance measured with ^(99m)Tc-GSA single-photon emission computed tomography to estimate liver fibrosis

AIM: To evaluate the clinical utility of hepatic clearance(HC) measured with technetium-99m-diethylenetriaminepenta-acetic acid-galactosyl human serum albumin(99mTc-GSA) single-photon emission computed tomography(SPECT) to estimate the degree of liver fibrosis.METHODS:Seventy-eight consecutive patients who underwent initial hepatectomy due to hepatocellular carcinoma were enrolled in this study.Indocyanine green clearance(ICG R15),quantitative indices estimated by 99mTc-GSA[the receptor index(LHL15 and HH15)and HC via SPECT analysis],and conventional liver function tests were performed before hepatectomy.Correlations among the quantitative indices for liver functional reserve,conventional liver function tests,andthe degree of liver fibrosis were evaluated.RESULTS:The degree of liver fibrosis was correlated with ICG R15,HH15,LHL15,and HC.HC showed the best correlation with conventional liver function tests.According to multivariate analysis,HC and LHL15 were significant independent predictors of severe fibrosis.HC was the most valuable index for predicting severe fibrosis.CONCLUSION:HC measured with 99mTc-GSA SPECT is a reliable index for assessing liver fibrosis before hepatectomy.

Cerebral functional imaging of Waiguan (SJ 5) acupoint specificity using single-photon emission computed tomography

The action of needling in acupoint therapy has to first be regulated and integrated by the brain, and then it affects the target organ and manifests its therapeutic effects, which is dependent on the specificity of the acupoints. The authors put forward the hypothesis of the ＂acupoint-related brain＂. Single-photon emission computed tomography was used to explore the activation of brain regions following true needling in true acupoint Waiguan （SJ 5）, sham needling in true acupoint Waiguan, true needling in a sham point, and sham needling in a sham point. The relative specificity of Waiguan in normal persons was analyzed by observing changes in regional cerebral blood flow. Compared with the sham needling in true acupoint group and sham needling in the sham point group, acupuncture at Waiguan can activate brain regions controlling movement. Compared with true needling in the sham point group, acupuncture at Waiguan can also activate brain regions controlling movement. The results suggest that the specificity of needling at an acupoint is related to certain activated cerebral functional regions, which are associated with the clinical application of the acupoint.

ASSESSMENT OF MYOCARDIAL VIABILITY WITH CONTRAST-ENHANCED MAGNETIC RESONANCE IMAGING AND COMPARISON WITH SINGLE-PHOTON EMISSION COMPUTED TOMOGRAPHY

Objective To compare contrast-enhanced magnetic resonance imaging （ceMRI） with nuclear metabolic imaging for the assessment of myocardial viability in patients with chronic ischemic heart disease. Methods Twenty patients with suspected chronic ischemic heart disease underwent ceMRI and technetium-99m sestamibi single-photon emission computed tomography （SPECT）. Patients with positive SPECT results also underwent 18 F-fluorodeoxyglucose （FDG） SPECT. In a 17-segment model, the segmental extent of hyperenhancement （SEH） by ceMRI was compared with segmental FDG and sestamibi uptake by SPECT. Correlation between the extent of hyperenhancement by ceMRI and left ventricular function was analyzed. Seven patients got negative results both in ceMRI and technetium-99m sestamibi SPECT. The rest 13 patients with positive results then underwent ^18F-FDG SPECT. In 221 segments of 13 patients, SEH was （2. 1±8.2）%, （25.0±13.7 ）%, and （57. 7±23.6 ）% in segments with normal metabolism/perfusion, metabolism/perfusion mismatch, and matched defects, respectively, and there were significant differences between either two of them （ all P 〈 0.05）. By receiver operating characteristic curve analysis, the area under the curve was 0. 95 for the differentiation between viable and non-viable segments. At the cutoff value of 34%, SEH optimally differentiated viable from non-viable segments defined by SPECT. Using this threshold, the sensitivity and specificity of ceMRI to detect non-viable myocardium as defined by SPECT were 92% and 93%, respectively. Hyperenhancement size by ceMRI was correlated negatively with the left ventricular ejection fraction （ r = - 0.90, P 〈 0.01 ） and positively with left ventricular volumes （ r = 0. 62 for end-diastolic volume, r = 0.75 for end-systolic volume, both P 〈 0.05 ）. Conclusion CeMRI allows assessment of myocardial viability with a high accuracy in patients with chronic ischemic heart disease.

Indocyanine green plasma clearance rate and 99mTc-galactosyl human serum albumin single-photon emission computed tomography evaluated preoperative remnant liver

BACKGROUND Preoperative evaluation of future remnant liver reserves is important for safe hepatectomy.If the remnant is small,preoperative portal vein embolization(PVE)is useful.Liver volume analysis has been the primary method of preoperative evaluation,although functional examination may be more accurate.We have used the functional evaluation liver using the indocyanine green plasma clearance rate(KICG)and 99mTc-galactosyl human serum albumin single-photon emission computed tomography(99mTc-GSA SPECT)for safe hepatectomy.AIM To analyze the safety of our institution’s system for evaluating the remnant liver reserve.METHODS We retrospectively reviewed the records of 23 patients who underwent preoperative PVE.Two types of remnant liver KICG were defined as follows:Anatomical volume remnant KICG(a-rem-KICG),determined as the remnant liver anatomical volume rate×KICG;and functional volume remnant KICG(frem-KICG),determined as the remnant liver functional volume rate based on 99mTc-GSA SPECT×KICG.If either of the remnant liver KICGs were>0.05,a hepatectomy was performed.Perioperative factors were analyzed.We defined the marginal group as patients with a-rem-KICG of<0.05 and a f-rem-KICG of>0.05 and compared the postoperative outcomes between the marginal and not marginal(both a-rem-KICG and f-rem-KICG>0.05)groups.RESULTS All 23 patients underwent planned hepatectomies.Right hepatectomy,right trisectionectomy and left trisectionectomy were in 16,6 and 1 cases,respectively.The mean of blood loss and operative time were 576 mL and 474 min,respectively.The increased amount of frem-KICG was significantly larger than that of a-rem-KICG after PVE(0.034 vs 0.012,P=0.0273).The not marginal and marginal groups had 17(73.9%)and 6(26.1%)patients,respectively.The complications of Clavian-Dindo classification grade II or higher and post-hepatectomy liver failure were observed in six(26.1%)and one(grade A,4.3%)patient,respectively.The 90-d mortality was zero.The marginal group had no significant difference in postoperative outcomes(prothrombin time/international normalised ratio,total bilirubin,complication,post-hepatectomy liver failure,hospital stay,90-d,and mortality)compared with the not-marginal group.CONCLUSION Functional evaluation of the remnant liver enabled safe hepatectomy and may extend the indication for hepatectomy after PVE treatment.

Single-Photon Emission from GaAs Quantum Dots Embedded in Nanowires

A highly efficient single-photon source based on a semiconductor quantum dot （QD） is a promising candidate in quantum information processing. We report a single-photon source based on self-assembled GaAs QDs in nanowires with an extraction efficiency of 14%. The second-order correlation function g（2） （0） at saturate excitation power is estimated to be 0.28. The measured polarization of QD emission depends on the geometric relations between the directions of PL collection and the long axis of nanowires.

Dopamine transporter distribution in patients with Parkinson disease of different stages detected using single-photon emission computed tomography brain imaging

BACKGROUND： Literatures have reported that the density changes of dopamine transporter is negatively correlated with the severity degree and grading of disease condition of Parkinson disease （PD）. However, the distribution ofdopamine transporter in each nucleus of corpora striatum at each period is still unclear. OBJECTIVE： To observe the radioactive uptake distribution of dopamine transporter in bilateral corpora striata of patients with different stages of PD using single photon emission computed tomography （SPECT）, and make a comparison with healthy controls. DESIGN： Case-control analysis. SETTING： Department of Imageology, Second Hospital Affiliated to Guangzhou University of Chinese Medicine. PARTICIPANTS： Thirty patients with PD admitted to Second Hospital Affiliated to Guangzhou University of Traditional Chinese Medicine between January and December 2005 were recruited. The involved patients, 19 male and 11 female, were aged from 36 to 80 years and with disease course of 2.5 months to 10 years. They all met the clinical diagnosis criteria of Britain Parkinson＇s disease Association Think Tank; Following Hoehn-Yahr grading： grade Ⅰ ： unilateral morbidity; grade Ⅱ： bilateral morbidity, but without balance disorder; grade Ⅲ： bilateral morbidity, accompanied with early posture balance disorder; grade Ⅳ： severe morbidity, needs more help; grade V ： without help, only in bed or wheelchair. There were 11 patients with mild PD （grade Ⅰ - Ⅱ ）, 9 patients with moderate PD （grade Ⅲ） and 10 patients with advanced PD （grade Ⅳ - Ⅴ ）. Meanwhile, 6 healthy persons were selected as normal controls. Informed consents were obtained from all the subjects. METHODS： Twenty-four hours after withdrawal of PD drugs, 30 patients with PD and 6 healthy controls took kalium perchloricum 400 mg orally. After lying down for 30 minutes, all the subjects were intravenously injected with 740 MBq 99Tc m-TRODAT-1 （Jiangsu Institute of Atomic Medicine, Batch No. 20040310） at elbow part. Following injection, image was collected using scanner for single photon emission computed tomography （ADAC Company, USA）. Matrix was 64 × 64, each detecting head revolved 180 ° , 1 frame/60 s. Sixty-four frames were collected with double detecting heads, 50 K/frame. Faultages with clearest image of corpora striatum were selected. Regions of interest （ROI） of caudate nucleus, anterior and posterior putamen and thalamic region in bilateral corpora striata were radioactively counted, and mean value of radioactive counting of ROI was used as the mean value ofpixel in each region of bilateral corpora striata. MAIN OUTCOME MEASURES： Comparison of radioactive uptake in each region of brain between healthy persons and patients with PD. RESULTS： Thirty patients with PD and six healthy persons who received body examination participated in the final result. Comparison of radioactive uptake in each region between healthy persons and patients with PD： ①In the healthy persons, high-density radioactive uptake was found in bilateral corpora striata; Structures of caudate nucleus, anterior and posterior putamen, and thalamus were clear with eudipleural radioactive distribution, and the background of peripheral brain tissue was very low. ②Radioactive intakes in opposite anterior and posterior putamen of patients with mild PD were significantly inferior to those in homolateral ones（70.45±3.35, 87.64±2.65, t =15.82, P 〈 0.05）. Structures of bilateral caudate nucleus and thalamus were clear with eudipleural radioactive distribution （P 〉 0.05）. ③Radioactive intakes in anterior and posterior putamen and thalamus of patients with moderate PD were significantly reduced as compared with healthy persons. There were significant differences in mean radioactive counting of ROI between patients with PD and healthy persons （t =5.20, P 〈 0.05： t =3.95, P 〈 0.05）; The structure of opposite caudate nucleus was not very clear, radioactive distribution of opposite caudate nucleus was significantly reduced as compared with homolateral one （81.11±4.25, 104.56±3.64, t = 14.65, P 〈 0.05）. ④As for patients with advanced PD, the structure of bilateral corpora striata was not clear, radioactive intake was significantly reduced and peripheral background was heightened, even higher than the distribution of the whole corpora striatum. CONCLUSION： SPECT DAT imaging of brain can show the distribution of radioactive uptake in each region of bilateral corpora striata of patients with different stages of PD, which is helpful to diagnose and evaluate the severity of PD.

Rest Thallium-201/Stress Technetium-99m Sestamibi Dual-Isotope Myocardial Perfusion Single-Photon Emission Computed Tomography in Detecting of Chronic Coronary Artery Disease

To investigate diagnostic accuracy of 2-hour protocol of rest thallium-201/stress technetium-99m sestamibi dual-isotope myocardial perfusion SPECT in chronic coronary artery disease. Sixty-seven patients with suspected CAD were enrolled in the prospective study. All patients underwent myocardial perfusion scintigraphy in SPECT with dual isotopes of T1-201 and dipyridamole stress Tc-99m sestamibi. Rest and stress imaging protocol were performed in 2 hours by dose of 3 mCi TI-201 and 25 mCi Tc-99m sestamibi. The acquisition parameters includes LEHR collimator, energy peak of 72 and 167 keV for T1-201 and 140 keV for Tc-99m, 180-degree rotation from RAO to LPO, matrix size 64x64, and 25second/frame/64 frames. The 20-segment model of left ventricle was used in automatic quantitation software. Coronary angiography was used as gold standard. CAD was defined as 50% of lumen stenosis on coronary angiography. Rest TI-201/stress tc-99m sestamibi dual-isotope SPECT demonstrated a sensitivity of 94.59% and specificity of 70%, positive predictive value of 79.54% and negative predictive value of 91.3% in detection of coronary artery disease. Sensitivity and specificity for detecting multi-vessel coronary artery disease were 82.75% and 81.57% for the left anterior descending, 77.77% and 91.83% for left circumflex and 94.11% and 82% for right coronary artery. 2-hour protocol of rest thallium-201/stress technetium-99m sestamibi dual-isotope myocardial perfusion SPECT has high sensitivity, specificity, positive predictive value and negative predictive value in detecting chronic coronary artery disease with greater than 50% stenosis assessed by coronary angiography Moreover, this imaging protocol gives high imaging quality, time-saving and convenience.

Carbon emission reduction:Contribution of photovoltaic power and practice in China

As a clean and renewable form of energy,photovoltaic(PV)power generation converts solar energy into electrical energy,reducing the consumption of fossil fuels and significantly lowering greenhouse gas emissions.Amidst the global transition towards cleaner forms of energy,countries all around the world are vigorously developing PV technology.

Global hybrid simulations of soft X-ray emissions in the Earth’s magnetosheath

Earth’s magnetopause is a thin boundary separating the shocked solar wind plasma from the magnetospheric plasmas,and it is also the boundary of the solar wind energy transport to the magnetosphere.Soft X-ray imaging allows investigation of the large-scale magnetopause by providing a two-dimensional(2-D)global view from a satellite.By performing 3-D global hybrid-particle-in-cell(hybrid-PIC)simulations,we obtain soft X-ray images of Earth’s magnetopause under different solar wind conditions,such as different plasma densities and directions of the southward interplanetary magnetic field.In all cases,magnetic reconnection occurs at low latitude magnetopause.The soft X-ray images observed by a hypothetical satellite are shown,with all of the following identified:the boundary of the magnetopause,the cusps,and the magnetosheath.Local X-ray emissivity in the magnetosheath is characterized by large amplitude fluctuations(up to 160%);however,the maximum line-of-sight-integrated X-ray intensity matches the tangent directions of the magnetopause well,indicating that these fluctuations have limited impact on identifying the magnetopause boundary in the X-ray images.Moreover,the magnetopause boundary can be identified using multiple viewing geometries.We also find that solar wind conditions have little effect on the magnetopause identification.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)mission will provide X-ray images of the magnetopause for the first time,and our global hybrid-PIC simulation results can help better understand the 2-D X-ray images of the magnetopause from a 3-D perspective,with particle kinetic effects considered.

Industrial Carbon Emission Distribution and Regional Joint Emission Reduction:A Case Study of Cities in the Pearl River Basin,China

China’s low-carbon development path will make significant contributions to achieving global sustainable development goals.Due to the diverse natural and economic conditions across different regions in China,there exists an imbalance in the distribution of car-bon emissions.Therefore,regional cooperation serves as an effective means to attain low-carbon development.This study examined the pattern of carbon emissions and proposed a potential joint emission reduction strategy by utilizing the industrial carbon emission intens-ity(ICEI)as a crucial factor.We utilized social network analysis and Local Indicators of Spatial Association(LISA)space-time trans-ition matrix to investigate the spatiotemporal connections and discrepancies of ICEI in the cities of the Pearl River Basin(PRB),China from 2010 to 2020.The primary drivers of the ICEI were determined through geographical detectors and multi-scale geographically weighted regression.The results were as follows:1)the overall ICEI in the Pearl River Basin is showing a downward trend,and there is a significant spatial imbalance.2)There are numerous network connections between cities regarding the ICEI,but the network structure is relatively fragile and unstable.3)Economically developed cities such as Guangzhou,Foshan,and Dongguan are in the center of the network while playing an intermediary role.4)Energy consumption,industrialization,per capita GDP,urbanization,science and techno-logy,and productivity are found to be the most influential variables in the spatial differentiation of ICEI,and their combination in-creased the explanatory power of the geographic variation of ICEI.Finally,through the analysis of differences and connections in urban carbon emissions under different economic levels and ICEI,the study suggests joint carbon reduction strategies,which are centered on carbon transfer,financial support,and technological assistance among cities.

Carbon Emission Effects Driven by Evolution of Chinese Dietary Structure from 1987 to 2020

Exploring carbon emission effects based on the evolution of residents’ dietary structure to achieve the carbon neutrality goal and mitigate climate change is an important task.This study took China as the research object(data excluding Hong Kong,Macao and Taiwan) and used the carbon emission coefficient method to quantitatively measure the food carbon emissions from 1987–2020,then analyzed the carbon emission effects under the evolution of dietary structure.The results showed that during the study period,the Chinese dietary structure gradually changed to a high-carbon consumption pattern.The dietary structure of urban residents developed to a balanced one,while that of rural residents developed to a high-quality one.During the study period,the per capita food carbon emissions and total food consumption of Chinese showed an increasing trend.The per capita food carbon emissions of residents in urban and rural showed an overall upward trend.The total food carbon emissions in urban increased significantly,while that in rural increased first and then decreased.The influence of beef and mutton on carbon emissions is the highest in dietary structure.Compared with the balanced dietary pattern,the food carbon emissions of Chinese residents had not yet reached the peak,but were evolving to a high-carbon consumption pattern.

Mechanical properties and acoustic emission characteristics of soft rock with different water contents under dynamic disturbance

Uniaxial compression tests and cyclic loading acoustic emission tests were conducted on 20%,40%,60%,80%,dry and saturated muddy sandstone by using a creep impact loading system to investigate the mechanical properties and acoustic emission characteristics of soft rocks with different water contents under dynamic disturbance.The mechanical properties and acoustic emission characteristics of muddy sandstones at different water contents were analysed.Results of experimental studies show that water is a key factor in the mechanical properties of rocks,softening them,increasing their porosity,reducing their brittleness and increasing their plasticity.Under uniaxial compression,the macroscopic damage characteristics of the muddy sandstone change from mono-bevel shear damage and‘X’type conjugate bevel shear damage to a roadway bottom-drum type damage as the water content increases.Dynamic perturbation has a strengthening effect on the mechanical properties of samples with 60%and less water content,and a weakening effect on samples with 80%and more water content,but the weakening effect is not obvious.Macroscopic damage characteristics of dry samples remain unchanged,water samples from shear damage and tensile–shear composite damage gradually transformed into cleavage damage,until saturation transformation monoclinic shear damage.The evolution of acoustic emission energy and event number is mainly divided into four stages:loading stage(Ⅰ),dynamic loading stage(Ⅱ),yield failure stage(Ⅲ),and post-peak stage(Ⅳ),the acoustic emission characteristics of the stages were different for different water contents.The characteristic value of acoustic emission key point frequency gradually decreases,and the damage degree of the specimen increases,corresponding to low water content—high main frequency—low damage and high water content—low main frequency—high damage.

Repositioning fertilizer manufacturing subsidies for improving food security and reducing greenhouse gas emissions in China

China removed fertilizer manufacturing subsidies from 2015 to 2018 to bolster market-oriented reforms and foster environmentally sustainable practices.However,the impact of this policy reform on food security and the environment remains inadequately evaluated.Moreover,although green and low-carbon technologies offer environmental advantages,their widespread adoption is hindered by prohibitively high costs.This study analyzes the impact of removing fertilizer manufacturing subsidies and explores the potential feasibility of redirecting fertilizer manufacturing subsidies to invest in the diffusion of these technologies.Utilizing the China Agricultural University Agri-food Systems model,we analyzed the potential for achieving mutually beneficial outcomes regarding food security and environmental sustainability.The findings indicate that removing fertilizer manufacturing subsidies has reduced greenhouse gas(GHG)emissions from agricultural activities by 3.88 million metric tons,with minimal impact on food production.Redirecting fertilizer manufacturing subsidies to invest in green and low-carbon technologies,including slow and controlled-release fertilizer,organic-inorganic compound fertilizers,and machine deep placement of fertilizer,emerges as a strategy to concurrently curtail GHG emissions,ensure food security,and secure robust economic returns.Finally,we propose a comprehensive set of government interventions,including subsidies,field guidance,and improved extension systems,to promote the widespread adoption of these technologies.

Hybrid-Vlasov simulation of soft X-ray emissions at the Earth’s dayside magnetospheric boundaries

Solar wind charge exchange produces emissions in the soft X-ray energy range which can enable the study of near-Earth space regions such as the magnetopause,the magnetosheath and the polar cusps by remote sensing techniques.The Solar wind Magnetosphere Ionosphere Link Explorer(SMILE)and Lunar Environment heliospheric X-ray Imager(LEXI)missions aim to obtain soft Xray images of near-Earth space thanks to their Soft X-ray Imager(SXI)instruments.While earlier modeling works have already simulated soft X-ray images as might be obtained by SMILE SXI during its mission,the numerical models used so far are all based on the magnetohydrodynamics description of the space plasma.To investigate the possible signatures of ion-kinetic-scale processes in soft Xray images,we use for the first time a global hybrid-Vlasov simulation of the geospace from the Vlasiator model.The simulation is driven by fast and tenuous solar wind conditions and purely southward interplanetary magnetic field.We first produce global X-ray images of the dayside near-Earth space by placing a virtual imaging satellite at two different locations,providing meridional and equatorial views.We then analyze regional features present in the images and show that they correspond to signatures in soft X-ray emissions of mirrormode wave structures in the magnetosheath and flux transfer events(FTEs)at the magnetopause.Our results suggest that,although the time scales associated with the motion of those transient phenomena will likely be significantly smaller than the integration time of the SMILE and LEXI imagers,mirror-mode structures and FTEs can cumulatively produce detectable signatures in the soft X-ray images.For instance,a local increase by 30%in the proton density at the dayside magnetopause resulting from the transit of multiple FTEs leads to a 12%enhancement in the line-of-sight-and time-integrated soft X-ray emissivity originating from this region.Likewise,a proton density increase by 14%in the magnetosheath associated with mirror-mode structures can result in an enhancement in the soft X-ray signal by 4%.These are likely conservative estimates,given that the solar wind conditions used in the Vlasiator run can be expected to generate weaker soft X-ray emissions than the more common denser solar wind.These results will contribute to the preparatory work for the SMILE and LEXI missions by providing the community with quantitative estimates of the effects of small-scale,transient phenomena occurring on the dayside.

Effects of drive imbalance on the particle emission from a Bose-Einstein condensate in a one-dimensional lattice

Time-periodic driving has been an effective tool in the field of nonequilibrium quantum dynamics,which enables precise control of the particle interactions.We investigate the collective emission of particles from a Bose-Einstein condensate in a one-dimensional lattice with periodic drives that are separate in modulation amplitudes and relative phases.In addition to the enhancement of particle emission,we find that amplitude imbalances lead to energy shift and band broadening,while typical relative phases may give rise to similar gaps.These results offer insights into the specific manipulations of nonequilibrium quantum systems with tone-varying drives.

A dual-route optical emission spectroscopy diagnostic with wide spectral range and high wavelength resolution on HL-2A tokamak

A dual-route optical emission spectroscopy(D-OES)diagnostic is newly developed to monitor the optical emission from the X-point plasma region on the HL-2 A tokamak.This diagnostic is composed of an imaging system,a beam-splitting system for dual-route measurements,fiber bundles,a spectrometer system,and a control and acquisition system.One route is used to obtain wide-spectral-range spectra,and the other route is used to acquire high-wavelengthresolution line shapes.The spectral resolution of the wide-range spectrometers is 0.8 nm with a coverage of 800 nm(@200-1000 nm).The spectral resolution of the high-resolution spectrometer is 0.01 nm with a coverage of 6 nm(@200-660 nm).The spatial resolution of each route of D-OES is about 4 cm with 11 channels.The temporal resolution is 16 ms at maximum in the single-channel mode.Wide-range spectra(containing Balmer series and a Fulcher band)and highly resolved Ha line shapes are obtained by D-OES in the hydrogen glow discharge in the lab.D-OES measurements are carried out in the high-density deuterium experiments of HL-2A.The electron density n_(e)and deuterium temperature T_(D) in the X-point multifaceted asymmetric radiation from the edge(MARFE)region are derived simultaneously by fitting the measured D_(a) shape.The density n_(e)is observed to increase from~8.7×10^(18)m^(-3)to~7.8×10^(19)m^(-3),and the temperature T_(D)drops from~14.4 eV to~2.3 eV after the onset of MARFE in the discharge#38260.

Effect of rice cultivar on greenhouse-gas emissions from rice-fish co-culture

In aquaculture,co-culturing rice with fish may mitigate greenhouse-gas emissions.In this study,co-culture of four rice cultivars in a laboratory-scale rice–fish system reduced CH_(4)and N_(2)O emissions relative to fish monoculture.Differences in CH_(4)and N_(2)O emissions among rice cultivars primarily stem from the differential effects of rice plants on plant-mediated CH_(4)transport,CH_(4)oxidation and nitrogen absorption.

Performance and Emission Characteristics of a CRDI Diesel Engine Fuelled by SiO_(2) Nanoparticle-Waste Fat Biodiesel Blends

This study investigates the use of waste fat biodiesel(WFB)from the leather industry as a substitute for diesel fuel.Specifically,it examines the diesel engine performance of WFB,a blend of WFB and diesel(B50),and different blends of WFB and silicon dioxide(SiO_(2))nanoparticles(B50SiO_(2)40,B50SiO_(2)80,and B50SiO_(2)120μg/g).The results indicate that the B50SiO_(2)120 blend increases brake thermal efficiency by 10.03%compared to pure biodiesel but falls 1.93%short of neat diesel.Furthermore,the B50SiO_(2)120 mixture reduces smoke,hydrocarbon,and carbon monoxide emissions by 31.87%,34.14%,and 43.97%respectively,compared to diesel.However,the B50SiO_(2)120 blend shows a 4.91%increase in nitrogen oxide emissions compared to diesel.

Effect of speed humps on instantaneous traffic emissions in a microscopic model with limited deceleration capacity

As a common transportation facility, speed humps can control the speed of vehicles on special road sections to reduce traffic risks. At the same time, they also cause instantaneous traffic emissions. Based on the classic instantaneous traffic emission model and the limited deceleration capacity microscopic traffic flow model with slow-to-start rules, this paper has investigated the impact of speed humps on traffic flow and the instantaneous emissions of vehicle pollutants in a single lane situation. The numerical simulation results have shown that speed humps have significant effects on traffic flow and traffic emissions. In a free-flow region, the increase of speed humps leads to the continuous rise of CO_(2), NO_(X) and PM emissions. Within some density ranges, one finds that these pollutant emissions can evolve into some higher values under some random seeds. Under other random seeds, they can evolve into some lower values. In a wide moving jam region, the emission values of these pollutants sometimes appear as continuous or intermittent phenomenon. Compared to the refined Na Sch model, the present model has lower instantaneous emissions such as CO_(2), NO_(X) and PM and higher volatile organic components(VOC) emissions. Compared to the limited deceleration capacity model without slow-to-start rules, the present model also has lower instantaneous emissions such as CO_(2), NO_(X) and PM and higher VOC emissions in a wide moving jam region. These results can also be confirmed or explained by the statistical values of vehicle velocity and acceleration.