Desert Abiotic Carbon Sequestration Weakening by Precipitation.

Desert carbon sequestration plays an active role in promoting carbon neutralization. However, the current understanding of the effect of hydrothermal interactions and soil properties on desert carbon sequestration after precipitation remains unclear. Based on the experiment in the hinterland of the Taklimakan Desert, we found that the heavy precipitation will accelerate the weakening of abiotic carbon sequestration in deserts under the background of global warming and intensified water cycle. The high soil moisture can significantly stimulate sand to release CO2 at an incredible speed by rapidly increasing microbial activity and organic matter diffusion. At this time, the CO2 flux in the shifting sand was synergistically affected by soil temperature and soil moisture. As far as soil properties are concerned, with less organic carbon substrate and stronger soil alkalinity, the carbon sequestration of shifting sand is gradually highlighted and strengthened at low temperature. On the contrary, the carbon sequestration of shifting sand is gradually weakened. Our study provides a new way to assess the contribution of desert to the global carbon cycle and improve the accuracy and scope of application.

Declining Oxygen Level as an Emerging Concern to Global Cities.

Rising CO2 concentration and temperatures in urban areas are now well-known, but the potential of an emerging oxygen crisis in the world's large cities has so far attracted little attention from the science community. Here, we investigated the oxygen balance and its related risks in 391 global large cities (with a population of more than 1 million people) using the oxygen index (OI), which is the ratio of oxygen consumption to oxygen production. Our results show that the global urban areas, occupying only 3.8% of the global land surface, accounted for 39% (14.3 ± 1.5 Gt/yr) of the global terrestrial oxygen consumption during 2001-2015. We estimated that 75% of cities with a population more than 5 million had an OI of greater than 100. Also, cities with larger OI values were correlated with more frequent heatwaves and severe water withdrawals. In addition, cities with excessively large OI values would likely experience severe hypoxia in extremely calm weather. Thus, mitigation measures should be adopted to reduce the urban OI in order to build healthier and more sustainable cities.

Feasibility Analysis of Using Channel State Information (CSI) Acquired from Wi-Fi Routers for Construction Worker Fall Detection.

Accidental falls represent a major cause of fatal injuries for construction workers. Failure to seek medical attention after a fall can significantly increase the risk of death for construction workers. Wearable sensors, computer vision, and manual techniques are common modalities for detecting worker falls in the literature. However, they are severely constrained by issues such as cost, lighting, background, clutter, and privacy. To address the problems associated with the existing proposed methods, a new method has been conceived to identify construction worker falls by analyzing the CSI signals extracted from commercial Wi-Fi routers. In this research context, our study aimed to investigate the potential of using Channel State Information (CSI) to identify falls among construction workers. To achieve the aim of this study, CSI data corresponding to 360 sets of activities were collected from six construction workers on real construction sites. The results indicate that (1) the behavior of construction workers is highly correlated with the magnitude of CSI, even in real construction sites, and (2) the CSI-based method for identifying construction worker falls has an accuracy of 99% and can also accurately distinguish between falls and fall-like actions. The present study makes a significant contribution to the field by demonstrating the feasibility of utilizing low-cost Wi-Fi routers for the continuous monitoring of fall incidents among construction workers. To the best of our knowledge, this is the first investigation to address the issue of fall detection using commercial Wi-Fi devices in real-world construction environments. Considering the dynamic nature of construction sites, the new method developed in this study helps to detect falls at construction sites automatically and helps injured construction workers to seek medical attention on time.

The evolution of ecological security and its drivers in the Yellow River Basin.

Ecological security is the state achieved once an ecosystem maintains its stability under external stress. The Yellow River Basin (YRB) is the largest river basin in northwest and north China and an important area for grain and energy production. The assessment and attribution of ecological security in the YRB are important for protecting the natural environment and ensuring sustainable development. Here, the ecological security of the YRB was assessed by the ecological security index (ESI), a comprehensive index based on the oxygen cycle, and its drivers were attributed to climate change, human activities, vegetation, and soil factors. The spatial pattern of ecological security in the YRB showed high heterogeneity. Ecological insecurity occurred mainly in the middle reaches and regions where the major stream of the Yellow River passes through. The ESI decreased at a rate of - 0.82/year since 2000, which indicated the natural environment continued to be improved in the YRB. Climate change dominated the evolution of ecological security in the upper reaches. The level of ecological security has been improved in the middle reaches after a series of ecological restoration projects conducted. With higher intensity of industrial activity, human activities played a more critical role in ecological security in the lower reaches. Our results suggested that government and local people need to adopt different strategies and actions based on the dominant drivers in the upper, middle, and lower reaches to ensure protection of the natural environment and achieve sustainable development targets.

Predicting ozone formation in petrochemical industrialized Lanzhou city by interpretable ensemble machine learning.

Ground-level ozone (O3) formation depends on meteorology, precursor emissions, and atmospheric chemistry. Understanding the key drivers behind the O3 formation and developing an accurate and efficient method for timely assessing the O3-VOCs-NOx relationships applicable in different O3 pollution events are essential. Here, we developed a novel machine learning ensemble model coupled with a Shapley additive explanation algorithm to predict the O3 formation regime and derive O3 formation sensitivity curves. The algorithm was tested for O3 events during the COVID-19 lockdown, a sandstorm event, and a heavy O3 pollution episode (maximum hourly O3 concentration >200 µg/m3) from 2019 to 2021. We show that increasing O3 concentrations during the COVID-19 lockdown and the heavy O3 pollution event were mainly caused by the photochemistry subject to local air quality and meteorological conditions. Influenced by the sandstorm weather, low O3 levels were mainly attributable to weak sunlight and low precursor levels. O3 formation sensitivity curves demonstrate that O3 formation in the study area was in a VOCs-sensitive regime. The VOCs-specific O3 sensitivity curves can also help make hybrid and timely strategies for O3 abatement. The results demonstrate that machine learning driven by observational data has the potential to be a very useful tool in predicting and interpreting O3 formation.

Divergent sensitivity of vegetation to aridity between drylands and humid regions.

The land surface has been drying over recent decades, which is inconsistent with the greening of the Earth. The extent and spatial variation in the sensitivity of vegetation to aridity changes in drylands and humid regions remain unclear. In this study, satellite observation and reanalysis data were used to analyze the relationship between vegetation growth and atmospheric aridity changes in different climatological regions on a global scale. Our results showed that the leaf area index (LAI) increased at a rate of 0.032/decade from 1982 to 2014, while the aridity index (AI) increased slightly at a rate of 0.005/decade. Over the past three decades, the sensitivity of the LAI to AI has decreased in drylands and increased in humid regions. Thus, the LAI and AI were decoupled in drylands, whereas the effect of aridity on vegetation was enhanced in humid regions during the study period. The physical and physiological effects of increasing CO2 concentration are responsible for the divergent responses of vegetation sensitivity to aridity in drylands and humid regions. The results of the structural equation models showed that the effect of increasing CO2 concentration via LAI and temperature, with respect to decreasing AI, enhanced the negative relationship between LAI and AI in humid regions. The greenhouse effect of increasing CO2 concentration resulted in an increase in temperature and a reduction in aridity, whereas the fertilization effect of CO2 increased LAI, thus creating an inconsistent trend with LAI and AI in drylands.

A Case Study on Tropical Bed Bug, Cimex hemipterus (Hemiptera: Cimicidae) Infestation and Management in Dormitories.

Numerous bed bug research papers have been published in the past 20 yr as a result of bed bug (Cimex spp.) (Hemiptera: Cimicidae) resurgence in the world. Yet, few of them focused on the management of the tropical bed bug, C. hemipterus (F.). Here, we describe a case of tropical bed bug infestation in two dormitory buildings and effectiveness of a tropical bed bug treatment program. The study site consisted of 125 dormitories in two buildings. An initial building-wide monitoring with ClimbUp interceptors revealed 25 infestations. The spatial distribution of bed bug infested rooms showed a significant aggregated distribution pattern with same infestation status for neighboring units sharing walls. All infested rooms were monitored every 2 wk and treated using a combination of steam and diatomaceous earth (DE) dust application if bed bugs were still found. For the 25 initially identified infested rooms, after 14 wk treatment, 44% of them no longer had bed bugs, and the mean number of bed bugs captured per room decreased by 94.1%. A combination of steam and DE dust treatment is an effective strategy for suppressing tropical bed bug infestations in dormitory environment.

Evaluation of carbon sink in the Taklimakan Desert based on correction of abnormal negative CO2 flux of IRGASON.

Studies showing that deserts can sequester CO2 through non-photosynthetic processes have contributed to locating missing carbon sinks. However, the contradiction between the desert CO2 flux obtained by different observation methods leads to uncertainty in evaluating desert carbon sequestration. This has caused scepticism regarding desert carbon sequestration after years of research. Through a comparative experiment in the non-vegetated shifting sand of the Taklimakan Desert (TD), it was found that if the abnormal negative CO2 flux observed by IRGASON during the day was not corrected, the carbon sequestration of the TD would be overestimated. The CO2 flux observed by EC155 is highly consistent with that of LI-COR8100A and can reflect the real CO2 exchange in the desert. The CO2 flux observed by EC155 was used to correct the results of IRGASON. Results show that the expansion/contraction of soil air containing CO2 caused by the change in the daily average soil temperature difference (T0-10cm) drives CO2 exchange in shifting sand. This results in diurnal variation of CO2 release caused by shifting sand during the day and CO2 absorption at night, and a unimodal distribution of CO2 exchange caused by shifting sand throughout the year. From April to September (T0-10cm > 2 °C), the shifting sand releases CO2 as a carbon source. In the other months (T0-10cm < 2 °C), the shifting sand absorbs CO2 as a carbon sink. The stronger absorption shows that the shifting sand in the TD provides carbon sequestration, with a CO2 uptake rate of ~148.85 × 104 tons a-1. This suggests that deserts play an active role in locating the missing carbon sinks and mitigating climate change, and that the status of deserts in the global carbon cycle cannot be ignored.

A Comparative Study on the Biological Characteristics of Parthenogenetic and Bisexual Restored Trichogramma pretiosum Lines.

In order to investigate the effect of Wolbachia on fitness of their hosts, the biological characteristics of a primarily parthenogenetic line and a bisexual restored line (obtained by antibiotic treatment) of Trichogramma pretiosum were compared in the laboratory. Results indicated that both the mean longevity and fecundity of parthenogenetic line (14.2 d and 165 eggs/female) were significantly higher than those in bisexual restored line (8.4 d and 124.2 eggs/female). Both lines of T. pretiosum had the highest daily fecundity (23.3 eggs/female for parthenogenetic line and 19.8 eggs/female for bisexual restored line) on the first day during their reproduction period, and their survival rate and daily fecundity decreased gradually with age; however, the survival rate and daily fecundity of the parthenogenetic line were always higher than those of bisexual restored line, during the entire experimental period. There was no significant difference in emergence rate and deformity rate between the two T. pretiosum lines. The life-table parameter results indicated that net reproduction rate (R0) and mean generation time (T) in parthenogenetic line (133 and 16.8) were significantly higher than those in bisexual restored line (61.7 and 15.5); intrinsic rate of natural increase (rm) and finite rate of increase (λ) in parthenogenetic line (0.29 and 1.34) were higher than those in bisexual restored line (0.26 and 1.3). Based on these results, it can be confirmed that the removal of Wolbachia in the parthenogenetic line had an adverse effect on fitness of T. pretiosum.

A case report of aggressive course of CD30+ primary cutaneous anaplastic large cell lymphoma.

INTRODUCTION: CD30+ primary cutaneous anaplastic large cell lymphoma (PC-ALCL) is a rare T-cell neoplasm, and has been reported to present with an indolent behavior. The PC-ALCL with aggressive behavior has not been reported in the literature. PATIENT CONCERNS: We treated a patient with PC-ALCL that exhibited indolent behavior in the past 2 years and aggressive behavior within the last 3 months before presentation. DIAGNOSIS: Aggressive CD30+ primary cutaneous anaplastic large cell lymphoma. INTERVENTIONS: The radiotherapy regimen was individualized in terms of the target volume delineation and dose prescription, and the dose-response relationship was evaluated. OUTCOMES: The mean distance of microscopic infiltration was 14.1 mm in depth and 14.3 mm circumferentially. The lesion completely regressed after the delivery of 40 Gy in 20 fractions over 4 weeks. The tumor did not recur over the next year. CONCLUSION: An aggressive disease course is rare for indolent CD30+ PC-ALCL, which has similar histopathological characteristics as indolent PC-ALCL. The radiotherapy strategy should be individualized with curative intent.

Morphological and Molecular Identification of Tropical Bed Bugs From Two Cities of the Pearl River Delta in China.

From the 1960s to the 1980s, with the implementation of nationwide 'Four-Pest Elimination' campaigns (bed bugs, Cimex lectularius L. and Cimex hemipterus (F.) (Hemiptera: Cimicidae), were listed as one of the targeted pests), bed bug infestations were gradually eliminated in most provinces in China. However, during the last two decades, reports of bed bug infestations in the Pearl River Delta of China have shown an upward trend. Up to now, the bed bug species occurring in this area was much less frequently reported. In this study, we used both morphological and molecular methods to accurately identify the species of bed bugs collected from the cities of Guangzhou and Foshan, China. Results indicated that no significant difference was observed in the mean pronotum width-to-length ratio of Guangzhou (2.6) and Foshan (2.4) specimens; however, both were significantly lower than that of a laboratory strain C. lectularius (3.1). The genetic distances of our specimens with C. hemipterus and C. lectularius were 0-0.2% and 22.2-22.6%, respectively. On the basis of the morphological characteristics and mitochondrial DNA sequence data, it can be affirmed that bed bugs collected from Guangzhou and Foshan were C. hemipterus.

Investigation of the eddy current effect on the high frequency response of the Mirnov probe on J-TEXT.

This paper investigates the high frequency response of the Mirnov probe based on a test platform, which is capable of generating a uniform AC magnetic field within the frequency range of 1-300 kHz. The eddy current effect is quantitatively reflected by the phase shift ϕc and normalized amplitude δ of the measured magnetic field between cases with and without a conducting plate located near the Mirnov probe. This method compensates the resonant effect in the Mirnov probe circuit and hence reflects purely the eddy current effect. The eddy current effect increases with the decrease in the distance between the probe and the conducting plate. With the increase in frequency, the magnitude of δ decreases to a saturated value at 10 kHz but increases significantly above 100 kHz for 304-stainless steel, while the eddy current effect with graphite appears at around 10 kHz and the magnitude of δ decreases to the minimum at 125 kHz, followed by a significant increase above 125 kHz. With the increase in f, the magnitude of ϕc increased until 2.5 kHz and 40 kHz for steel and graphite, respectively, then decreased with a further increase in f. The phasor expression is introduced to describe the AC magnetic field and allows an easy expression of the eddy current field. The phase of the eddy current field decreases toward -180° with f. The amplitude of the eddy current field increases with f and reaches its maximum when the skin depth reduces to a critical value. The eddy current field decreases with a further increase in the frequency.

[Intervention effect of tongfei mixture on nocturnal hypoxia in patients with chronic obstructive pulmonary disease].

OBJECTIVE: To study the effect of tongfei mixture (TFM, a Chinese recipe mainly consisted of angelica and rehmannia root) on nocturnal hypoxia in patients with chronic obstructive pulmonary disease (COPD). METHODS: Sixty patients with COPD of remission phase were randomly divided into 3 groups, 20 in each group. Group A was the control group; Group B, the group simply treated with oxygen; Group C, treated with oxygen and TFM. Changes of pulmonary function, diaphragm muscle mobility (DMM), 6 min walk distance (6MWD), morning arterial blood gas, nocturnal lowest oxygen saturation (LSaO2), mean blood oxygen saturation (MSaO2), the percentage of saturation lower than 90% time account for total sleeping time (SLT90%) and ultrasonocardiogram before and after treatment were observed. RESULTS: Levels of LSaO2, MSaO2 and SLT90% in Groups B and C were significantly higher than those in Group A (P<0.05, P<0.01). The lowering of PaCO2 in Group C was more significant than that in Group B (P<0.05). The mPAP level in Group C was lower, FEV1, 6MWD and DMM were improved than those in Group A and B, showing significant difference (P<0.05). CONCLUSION: Combined use of oxygen therapy and TFM could not only improve the nocturnal hypoxia, but also lower PaCO2. TFM is an important supplement of oxygen therapy.

[Effect of recombinant human erythropoietin on hippocampal p-Akt and caspase-9 expressions in rats with status epilepticus and the mechanism].

OBJECTIVE: To observe the effect of recombinant human erythropoietin (rhuEPO) on p-Akt and caspase-9 expressions in the hippocampus of rats with status epilepticus (SE) and explore the neuroprotective mechanism of rhuEPO. METHODS: Adult male SD rats were randomized into control, PTZ, rHuEPO, LY294002 group, and DMSO groups and treated with normal saline (NS), PTZ, PTZ+rHuEPO, PTZ+LY294002+rHuEPO, and PTZ+DMSO+rHuEPO, respectively. The behavioral and electroencephalogram (EEG) changes of the rats were recorded, and the expressions of p-Akt and caspase-9 were detected using immunohistochemistry. The hippocampal expression of caspase-9 mRNA was detected using RT-PCR, and the expressions of Akt and p-Akt proteins were determined with Western blotting. RESULTS: The p-Akt-positive cell and p-Akt protein expression increased significantly while the caspase-9-positive cell and caspase-9 mRNA expression decreased in rHuEPO group as compared with those in PTZ group (P<0.05). LY294002 treatment prior to rHuEPO injection significantly abolished the effects of rHuEPO on caspase-9 and p-Akt immunohistochemical positivity and caspase-9 mRNA and p-Akt protein expressions (P<0.05). CONCLUSION: Administration of rHuEPO activates the PI3K/Akt signaling pathway in SE rats and increases the expression of p-Akt protein to regulate the expression of caspase-9, a regulatory factor of the mitochondrial-dependent apoptotic pathway, and therefore provides anti-apoptotic and neuroprotective effects.