Detection of spatiotemporal changes in ecological quality in the Chinese mainland: Trends and attributes

Global climate change and revegetation programs have significantly changed the ecological quality (EQ) in the Chinese mainland after 1999. Monitoring and assessing the changes in the regional EQ and analyzing their drivers are crucial for ensuring ecological restoration and rehabilitation. However, it is challenging to carry out a long-term and large-scale quantitative assessment of the EQ of a region based on traditional field investigations and experiment methods alone; notably, in previous studies, the effects of carbon and water cycles and human activities on the variations in EQ have not been studied comprehensively. Therefore, in addition to remote sensing data and principal component analysis, we used the remote sensing-based ecological index (RSEI), to assess the EQ changes in the Chinese mainland during 2000-2021. Additionally, we also analyzed the impacts of carbon and water cycles and anthropological activities on the changes in the RSEI. The main conclusions of this study were: since the beginning of the 21st century, we observed a fluctuating upward trend in the EQ changes in the Chinese mainland and eight climatic regions. From 2000 to 2021, in terms of the EQ, North China (NN) portrayed the highest increase rate (2.02 × 10^-3 year^-1, P < 0.05). There was a breaking point in 2011, the EQ in the region experienced a change, from a downward trend to an upward one. Northwest China, Northeast China, and NN portrayed an overall significant increasing trend in the RSEI, whereas the southwest part of the Southwest Yungui Plateau (YG) and a part of the plain region of the Changjiang (Yangtze) River (CJ) river region portrayed a significant decreasing trend in the EQ. Overall, the carbon and water cycles and human activities played a pivotal role in determining the spatial patterns and trends of the EQ in the Chinese mainland. In particular, the self-calibrating Palmer Drought Severity Index, actual evapotranspiration (AET), gross primary productivity (GPP), and soil water content (Soil_w) were identified as the key drivers of the RSEI. In the central and western Qinghai-Tibetan Plateau (QZ) and the northwest region of NW, the changes in RSEI were dominated by AET; however, in central NN, southeastern QZ, northern YG, and central NE, the changes were driven by GPP, and in the southeast region of NW, south region of NE, northern region of NN, middle YG region, and a part of the middle CJ region, the changes were driven by Soil_w. The population-density-related change in the RSEI was positive in the northern regions (NN and NW) but negative in the southern regions (SE), whereas the RSEI change related to ecosystem services was positive in the NE, NW, QZ, and YG regions. These results are beneficial for the adaptive management and protection of the environment and the realization of green and sustainable developmental strategies in the Chinese mainland.

Trends in drought and effects on carbon sequestration over the Chinese mainland

Recently, drought events have occurred frequently and have profoundly altered the carbon sequestration in terrestrial ecosystems. How drought affects carbon sequestration is an important issue which may assist in understanding and confronting the challenges of extreme climate change. Nevertheless, drought-induced carbon-cycle effects remain scarce from the perspective of drought indices. In this study, we quantified the impacts of potential evapotranspiration (PET), standardized precipitation evapotranspiration index (SPEI), downward short-wave radiation flux (SWDown), and soil water (Soil_w) on net ecosystem productivity (NEP). We showed that the spatiotemporal heterogeneity of drought was extremely significant, and the hot spots of aridification were mainly distributed in the southwestern Yungui Plateau (YG) and Northwest China (NW). Moreover, the "pan evaporation paradox" appeared across the Chinese mainland before the 1990s and subsequently disappeared. Similarly, in contrast to the moderate NEP fluctuation between 1981 and 1999, since the beginning of the 21st century, NEP has increased significantly across Chinese mainland, YG, the plains region of Changjiang (CJ), and Southeast China (SE). Meanwhile, there are obvious directional, temporal, and spatial differences in the effects of the drought indices on NEP. Specifically, a higher SPEI value results in a more obvious promoting effect on NEP in SE, North China (NN), and northeastern YG. An increase in SWDown can promote an increase in NEP, especially in the northeastern YG and central SE. The increase in Soil_w in parts of the Qinghai-Tibetan Plateau, Xinjiang Region (XJ), southeastern NW, NN, and Northeast China with poor water conditions can promote carbon sinks. The inhibition effect is particularly obvious in some areas of CJ, where water resources are abundant. The fluctuation in PET has a relatively low influence on NEP. This study provides a comprehensive assessment of drought change and its impact on carbon sequestration and may help in formulating appropriate policies for carbon management and ecological security.

Spatial differentiation of carbon emissions from residential energy consumption: A case study in Kaifeng, China

Effective strategies, policies and measures for carbon emission reduction need to be developed and implemented according to good understanding of both local conditions and spatial differentiation mechanism of energy consumption associated with human activities at high resolution. In the study, we first collected statistical yearbooks, high resolution remotely sensed imageries, and 3895 usable questionnaires for the urban areas of Kaifeng; then measured the carbon emissions from household energy consumption, using the accounting method provided in the IPCC GHG Inventory Guidelines; and finally applied both exploratory and explanatory statistical methods to characterize the spatial pattern of carbon emissions at high resolution, identify key influencing factors, and gain better understanding of the spatial differentiation mechanism of urban residential carbon emissions. Our study reached the following conclusions: (1) Central heating facilities with controllable flow are important for carbon emissions reduction, but its spatial distribution shows unfairness; (2) Spatial clusters of high carbon emission areas were primarily located in the outer suburbs of the city, validated to some extent the hypothesis that urban sprawl has a driving effect on the increasing urban residential carbon emissions; (3) Factors like size of residential area, family structure, life style, personal preference and behavior rather than household income have significant impacts on household carbon emissions, implying that effective control of residential areas, promotion of family life and low-carbon lifestyle, and effective guidance of proper behaviors and preferences will play a crucial role in reducing urban residential carbon emissions; and (4) Most of the identified influencing factors exhibit clear and specific spatial patterns and gradients of impact, implying that measures for urban residential carbon emission reduction should be adapted to location conditions. The study has generated a set of concrete evidences and improved understandings of the spatially differentiated mechanisms upon which the formation and deployment of any effective strategies, policies and measures for reducing urban residential carbon emissions should be based.

Value Assessment of Health Losses Caused by PM2.5 Pollution in Cities of Atmospheric Pollution Transmission Channel in the Beijing⁻Tianjin⁻Hebei Region, China

A set of exposure–response coefficients between fine particulate matter (PM_2.5) pollution and different health endpoints were determined through the meta-analysis method based on 2254 studies collected from the Web of Science database. With data including remotely-sensed PM_2.5 concentration, demographic data, health data, and survey data, a Poisson regression model was used to assess the health losses and their economic value caused by PM_2.5 pollution in cities of atmospheric pollution transmission channel in the Beijing–Tianjin–Hebei region, China. The results showed the following: (1) Significant exposure–response relationships existed between PM_2.5 pollution and a set of health endpoints, including all-cause death, death from circulatory disease, death from respiratory disease, death from lung cancer, hospitalization for circulatory disease, hospitalization for respiratory disease, and outpatient emergency treatment. Each increase of 10 μg/m³ in PM_2.5 concentration led to an increase of 5.69% (95% CI (confidence interval): 4.12%, 7.85%), 6.88% (95% CI: 4.94%, 9.58%), 4.71% (95% CI: 2.93%, 7.57%), 9.53% (95% CI: 6.84%, 13.28%), 5.33% (95% CI: 3.90%, 7.27%), 5.50% (95% CI: 4.09%, 7.38%), and 6.35% (95% CI: 4.71%, 8.56%) for above-mentioned health endpoints, respectively. (2) PM_2.5 pollution posed a serious threat to residents’ health. In 2016, the number of deaths, hospitalizations, and outpatient emergency visits induced by PM_2.5 pollution in cities of atmospheric pollution transmission channel in the Beijing–Tianjin–Hebei region reached 309,643, 1,867,240, and 47,655,405, respectively, accounting for 28.36%, 27.02% and 30.13% of the total number of deaths, hospitalizations, and outpatient emergency visits, respectively. (3) The economic value of health losses due to PM_2.5 pollution in the study area was approximately $28.1 billion, accounting for 1.52% of the gross domestic product. The economic value of health losses was higher in Beijing, Tianjin, Shijiazhuang, Zhengzhou, Handan, Baoding, and Cangzhou, but lower in Taiyuan, Yangquan, Changzhi, Jincheng, and Hebi.

Development of EST-SSR markers related to disease resistance and their application in genetic diversity and evolution analysis in Gossypium

Cotton (Gossypium spp) is one of the most economically important crops that provide the world's most widely used natural fiber. Diseases such as Fusarium wilt and particularly Verticillium wilt seriously affect cotton production, and thus breeding for disease resistance is one of the most important goals of cotton breeding programs. Currently, potential exists to improve disease resistance in cultivated cotton. Increasing the understanding of the distribution, structure, and organization of genes or quantitative trait loci for disease resistance will help the breeders improve crop yield even in the event of disease. To facilitate the mapping of disease-resistance quantitative trait loci to achieve disease-resistant molecular breeding in cotton, it is necessary to develop polymorphic molecular markers. The objective of this study was to develop simple sequence repeat markers based on cotton expressed sequence tags for disease resistance. The efficacy of these simple sequence repeat markers, their polymorphisms, and cross-species transferability were evaluated. Their value was further investigated based on genetic diversity and evolution analysis. In this study, the unique sequences used to develop markers were compared with the G. arboretum and G. raimondii genome sequences to investigate their position, homology, and collinearity between G. arboretum and G. raimondii.

A functional MRI study of deception among offenders with antisocial personality disorders

Deceit is a core feature of antisocial personality disorder (ASPD), and the study of deception in ASPD has important implications for identifying the underlying mechanism of ASPD. A great deal of functional neuroimaging literature has described the neural correlates of deception in healthy volunteers, but there have been few imaging studies examining people with ASPD. The neural correlates of lie-telling in ASPD, and which specific brain activities are related to the capacity to lie, are unclear. In this study, 32 offenders who satisfied the Personality Diagnostic Questionaire-4 and PDI-IV (Personality Disorder Interview) criteria for ASPD were divided into three groups based on their capacity for deception, which was evaluated based on the deceitfulness criterion of the PDI-IV ASPD. All offenders underwent functional magnetic resonance imaging (fMRI) while responding to questions in a truthful, inverse, or deceitful manner. We primarily created contrasts in the brain activities between truth-telling and lie-telling, and then computed the Pearson's correlation coefficients between activities contrasts of individual, i.e. BOLD (blood-oxygen-level-dependent) strength during deception minus that during truth-telling, and the capacity for deception. Our results indicated that the bilateral dorsolateral prefrontal cortex extending to the middle frontal gyrus, the left inferior parietal lobule, and the bilateral anterior cingulate gyrus/medial superior frontal gyrus were associated with deception among people with ASPD. As the capacity for deception increased, the contrasted brain activities of the above regions decreased. This study found that truthful and untruthful communications of ASPD subjects can be differentiated in terms of brain BOLD activities, and more importantly, this study is the first to use fMRI to discover that BOLD activities during deception are correlated with the capacity to lie. The latter finding might challenge the diagnostic accuracy of lie detection and may also caution that greater attention should be given to detecting untruths in individuals who are skilled at lying.

Control of renin secretion from adrenal gland in transgenic Ren-2 and normal rats

In Ren-2 rats, plasma active renin and prorenin increase following binephrectomy (BNx) related to increasing plasma potassium. Adrenal is the source of the increasing prorenin but active renin comes mainly from thymus and gut. Trophic influences other than potassium were tested in the present work. Angiotensin did not influence the post-BNx increases in plasma active or prorenin but suppressed resting plasma prorenin from non-adrenal, non-renal sources virtually to zero. ACTH and histamine had no discernible effects. Hexamethonium decreased by 50% the post BNx increase in prorenin but not active renin. In Sprague-Dawley and spontaneously hypertensive rats, low levels of active renin secretion were detected from adrenal but no prorenin. Thus, in anesthetized Ren-2 rats, secreted prorenin is from two sources, i.e. extrarenal and extra-adrenal sites readily suppressible with angiotensin and the adrenal that is partly suppressible by autonomic blockage. This may assist in identifying the origin of extra-renal prorenin secreted in man.

Downregulation of the p75 neurotrophin receptor in tissue culture and in vivo, using beta-cyclodextrin-adamantane-oligonucleotide conjugates

Formation of complexes with beta-cyclodextrin derivatives via adamantyl groups was found to enhance the uptake and antisense efficacy of phosphorothioate oligos targeted to the p75 neurotrophin receptor in neuronally differentiated PC12 cells. After a 2-week course of systemic administration to mice (by intraperitoneal injection), there was evidence of a pronounced uptake of these oligos by the dorsal root ganglia (DRG), as well as by liver and kidney. There was no uptake by the brain. Consistent with uptake of antisense oligos by the DRG, systemic administration resulted in marked and consistent downregulation of p75 in DRG neurons. These results indicate that cyclodextrin-adamantane-oligo conjugates have great potential as agents to downregulate target genes in neurons, particularly in vivo in the peripheral nervous system.

Renin in thymus, gut, hindlimb, and adrenal of (mRen-2)27 and normal rats: secretion and content studies

Thymic ablation and assay of organ renin revealed that one-third of the increasing plasma level of active renin after removal of kidneys and adrenals from Ren-2 rats originates from the thymus. Splanchnic arteriovenous difference and renin content indicate that gut can account for the remainder. Secretion of active renin from these sites correlated significantly with increasing plasma potassium. Prorenin was not secreted from these sites or from hindlimb in amounts sufficient to raise the plasma level, and yet plasma prorenin remained higher than active renin throughout the 12-h protocol. The source of prorenin that accounts for the high plasma prorenin phenotype of the intact conscious Ren-2 rat was not specifically identified. When sensitive assays were used, a low level of active renin secretion from thymus and gut was also apparent 12 h after removal of kidneys and adrenals in normal Sprague-Dawley rats, and plasma prorenin was at this time higher than active renin. A likely source of this extrarenal, extra-adrenal renin is the macrophage.

Potassium control of extrarenal renin secretion in transgenic (mRen-2)27 and normal rats

Plasma active renin and prorenin were followed for 12 h after bilateral, unilateral, and sham nephrectomy (BNx, UNx, and SNx) in anesthetized transgenic (mRen-2)27 rats to compare them with Sprague-Dawley and spontaneously hypertensive rats (SDR and SHR). In Ren-2 rats, active renin and prorenin increased with plasma potassium post-BNx and were augmented by potassium infusion. The increase in prorenin but not active renin was abolished by bilateral adrenalectomy (BADRx). However, this did not reduce prorenin below normal, indicating that the high plasma prorenin Ren-2 phenotype is not only of adrenal origin. SNx and UNx also raised plasma active renin and prorenin in Ren-2 rats, with positive correlations to plasma potassium. In SDR and SHR, active renin fell below prorenin post-BNx, and adrenal ablation and potassium loading (in SDR) modified the decreasing active renin profile consistent with low levels of regulated extrarenal secretion. In Ren-2 rats, adrenal but not extra-adrenal prorenin secretion is potassium sensitive and stress related. The unidentified source of active renin in BNx+BADRx Ren-2 rats is also potassium and stress related.

Nerve growth factor determines survival and death of PC12 cells by regulation of the bcl-x, bax, and caspase-3 genes

We investigated the effects of nerve growth factor (NGF) and NGF withdrawal on expression of members of the bcl-2 family of genes and caspase-3 in PC12 cells. NGF regulated several members of the bcl-2 family and caspase-3 in a manner consistent with its effect on apoptosis in PC12 cells. Levels of bcl-xl, bcl-xs, and caspase-3 mRNAs were increased by NGF treatment. The increases in caspase-3 and bcl-xs levels should have disposed the cells toward apoptosis but were opposed by the simultaneous increase in bcl-xl level. NGF withdrawal resulted in abrupt down-regulation of bcl-xl and up-regulation of bax, favoring apoptosis. Forced expression of bcl-xl after NGF withdrawal was sufficient to prevent cell death. Cell death was rapid when NGF was withdrawn after 5 days of treatment but relatively slow when NGF was withdrawn after only 1 or 2 days of treatment. This was consistent with the reduced accumulation of caspase-3 mRNA with shorter NGF treatments. These results indicate that Bcl-xl, Bcl-xs, Bax, and caspase-3 are important regulators of apoptosis in PC12 cells. Furthermore, regulation of their mRNA levels is implicated in the signal transduction of NGF.

Enhanced downregulation of the p75 nerve growth factor receptor by cholesteryl and bis-cholesteryl antisense oligonucleotides

The effects of conjugating cholesterol to either or both ends of a phosphorothioate (PS) oligonucleotide were analyzed in terms of cellular uptake and antisense efficacy. The oligo sequence was directed against the p75 nerve growth factor receptor (p75), and was tested in differentiated PC12 cells, which express high levels of this protein. The addition of a single cholesteryl group to the 5'-end significantly increased cellular uptake and improved p75 mRNA downregulation compared with the unmodified PS oligo. However, only a minor degree of downregulation of p75 protein was obtained with 5' cholesteryl oligos. Three different linkers was used to attach the 5' cholesteryl group but were found not to have any impact on efficacy. Addition of a single cholesteryl group to the 3'-end led to greater p75 mRNA downregulation (31%) and p75 protein downregulation (28%) than occurred with the 5' cholesteryl oligos. The biggest improvement in antisense efficacy, both at the mRNA and protein levels, was obtained from the conjugation of cholesterol to both ends of the oligo. One of the bischolesteryl oligos was nearly as effective as cycloheximide at decreasing synthesis of p75. The bis-cholesteryl oligos also displayed significant efficacy at 1 microM, whereas the other oligos required 5 microM to be effective. The enhanced efficacy of bis-cholesteryl oligos is likely to be due to a combination of enhanced cellular uptake and resistance to both 5' and 3' exonucleases.

Complete inhibition of poly(ADP-ribose) polymerase activity prevents the recovery of C3H10T1/2 cells from oxidative stress

Activation of the poly(ADP-ribose) polymerase after oxidative damage is implicated in different responses of the cells, for example, cell recovery after sublethal damage or cell death after lethal damage. However, the extent and mechanism of involvement of the enzyme in these two processes appear to be different. Inhibitors of this polymerase, such as benzamides, which do not completely inhibit PARP have been shown to protect the cells from killing by massive oxidant damage, could neither reduce the cellular recovery after mild oxidant damage nor completely inhibit DNA repair in vitro. We report here that 1,5-dihydroxyisoquinoline, which was earlier shown to be a strong inhibitor of this polymerase in vitro, is also its potent inhibitor in vivo. Using sensitive techniques for measuring low levels of cellular poly(ADP-ribose) polymer, we show that this inhibitor can completely abolish oxidant-induced activation of the polymerase in C3H10T1/2 cells. We show that only a minor fraction of the poly(ADP-ribose) polymerase activity is sufficient in cellular recovery after sublethal oxidant damage. We also demonstrate that cells are unable to recover from oxidant damage in the complete absence of polymerase activity.

Angiotensin and bradykinin peptides in the TGR(mRen-2)27 rat

The transgenic TGR(mRen-2)27 rat, in which the Ren-2 mouse renin gene is transfected into the genome of the Sprague-Dawley rat, develops severe hypertension at a young age that responds to inhibitors of angiotensin-converting enzyme and to antagonists of the type 1 angiotensin II (Ang II) receptor. Despite this evidence that the hypertension is Ang II dependent, TGR(mRen-2)27 rats have suppressed renal renin and renin mRNA content, and there is controversy concerning the plasma levels of renin and Ang II in these rats. We investigated the effect of the transgene on circulating and tissue levels of angiotensin and bradykinin peptides in 6-week-old male homozygous TGR(mRen-2)27 rats. Systolic blood pressure of TGR(mRen-2)27 rats was 212 +/- 4 mm Hg (mean +/- SEM, n = 25) compared with 108 +/- 2 mm Hg (n = 29) for age- and sex-matched Sprague-Dawley rats. Compared with control rats, TGR(mRen-2)27 rats had increased plasma levels of active renin (4.5-fold), prorenin (300-fold), and Ang II (fourfold) as well as tissue levels of Ang II (twofold to fourfold in kidney, adrenal, heart, aorta, brown adipose tissue, and lung and 18-fold in brain). Plasma angiotensinogen levels were reduced to 73% of control, and plasma aldosterone levels were increased fourfold. Plasma angiotensin-converting enzyme was reduced to 64% of control. Compared with control rats, TGR(mRen-2)27 rats had increased bradykinin levels in brown adipose tissue (1.9-fold) and lung (1.6-fold).(ABSTRACT TRUNCATED AT 250 WORDS)

Renin processing and secretion in adrenal and retina of transgenic (mREN-2)27 rats

Two extrarenal tissue sources of renin were studied using quantitative assays and immunocytochemical methods during 12 hours following binephrectomy (BNx) in anesthetized hypertensive homozygous Ren-2 transgenic (TG) rats maintained off hypotensive drugs for three weeks. Compared to normal rats, circulating active renin was depressed 50% in conscious TG rats and prorenin was 5- to 10-fold higher. Post-BNx, arterial active and prorenin increased progressively to 10-fold, at which time adrenal venous outputs were 0.1 and 20 mGU/min, respectively. The ratio of active to prorenin (3.1 +/- 0.6%) remained unchanged with increasing plasma levels. Thus, either intrinsic enzyme activity of the transgenic prorenin contributed a constant proportion to the measured active renin, or processing to mature renin was coupled to prorenin synthesis and secretion in extrarenal tissues. In the TG rat eye, renin protein labeling was localized throughout retinal Müller cells with prosequence more obvious posteriorly, consistent with directional processing. Immunogold studies are in progress. In adrenal following BNx, labeling for renin and prosequence increased uniformaly in all zones of the cortex and in scattered medullary chromaffin cells. In cortex, both renin and prosequence were strongly located in intramitochondrial dense bodies. In chromaffin cells, renin labeling was present in both cytoplasmic vesicles and electron-dense granules, while prosequence was predominantly in cytoplasmic vesicles, consistent with processing of prorenin prior to storage in chromaffin granules.

Global depletion of myocardial norepinephrine and ATP after left coronary artery occlusion in rats

After ligation of the left coronary artery in rats, myocardial norepinephrine (NE) and ATP depletions in both infarcted (IZ) and non-infarcted zone (NIZ) were studied. In IZ, the depletions of NE and ATP were biphasic and the depleting rate constants were found to be K1 = 0.71 h-1 and K2 = 0.015 h-1 for NE, and K1' = 0.52 h-1 and K2' = 0.016 h-1 for ATP. In NIZ, the depletion of NE was monophasic, slowly progressive, and quite durable with rate constant K3 = 0.018 h-1. The depletion of ATP was transient. Propranolol (Pro) and verapamil (Ver) were beneficial but only partly effective against NE and ATP depletions.

Anti-arrhythmic activities of six indole derivatives of changrolin

The indole-derived compounds, which possessed side chains resembling those of changrolin (4-[3',5'-bis[(N-pyrrolidinyl)methyl]-4'-hydroxyaniline]-quinazoline) showed potent anti-arrhythmic activity by restoration of sinus rhythm from ouabain-induced tachycardia in guinea pigs. The potency was assessed by comparison of the maintenance time of sinus rhythm recovered from tachyarrhythmias induced by ouabain. The promising compound was MI2 with piperidyl residue on position 3 & 5 of phenol moiety. There was no difference in anti-arrhythmic activities resulting from substitutions between a benzene ring and methyl residue at position 2 of indole, but the latter had weaker parasympatholytic activity. The anti-arrhythmic activity of MI2 (greater than 60 min) was 2.4 times more potent then changrolin (25 min), but its anti-cholinergic activity was only half of the latter. To compare the suppressive effect on reperfusion-induced arrhythmias by iv MI2 at different time in relation to the ligation-reperfusion protocol, it was the most effective when administered either 30 min prior to coronary occlusion or at the moment of reperfusion. The compound MI might belong to the Ic group shown by the slowing impulse conduction within the heart.