The left inferior frontal gyrus is causally linked to vocal feedback control: evidence from high-definition transcranial alternating current stimulation.

Current models of speech motor control propose a role for the left inferior frontal gyrus (IFG) in feedforward control of speech production. There is evidence, however, that has implicated the functional relevance of the left IFG for the neuromotor processing of vocal feedback errors. The present event-related potential (ERP) study examined whether the left IFG is causally linked to auditory feedback control of vocal production with high-definition transcranial alternating current stimulation (HD-tACS). After receiving active or sham HD-tACS over the left IFG at 6 or 70 Hz, 20 healthy adults vocalized the vowel sounds while hearing their voice unexpectedly pitch-shifted by ±200 cents. The results showed that 6 or 70 Hz HD-tACS over the left IFG led to larger magnitudes and longer latencies of vocal compensations for pitch perturbations paralleled by larger ERP P2 responses than sham HD-tACS. Moreover, there was a lack of frequency specificity that showed no significant differences between 6 and 70 Hz HD-tACS. These findings provide first causal evidence linking the left IFG to vocal pitch regulation, suggesting that the left IFG is an important part of the feedback control network that mediates vocal compensations for auditory feedback errors.

Right, but not left, posterior superior temporal gyrus is causally involved in vocal feedback control.

The posterior superior temporal gyrus (pSTG) has been implicated in the integration of auditory feedback and motor system for controlling vocal production. However, the question as to whether and how the pSTG is causally involved in vocal feedback control is currently unclear. To this end, the present study selectively stimulated the left or right pSTG with continuous theta burst stimulation (c-TBS) in healthy participants, then used event-related potentials to investigate neurobehavioral changes in response to altered auditory feedback during vocal pitch regulation. The results showed that, compared to control (vertex) stimulation, c-TBS over the right pSTG led to smaller vocal compensations for pitch perturbations accompanied by smaller cortical N1 and larger P2 responses. Enhanced P2 responses received contributions from the right-lateralized temporal and parietal regions as well as the insula, and were significantly correlated with suppressed vocal compensations. Surprisingly, these effects were not found when comparing c-TBS over the left pSTG with control stimulation. Our findings provide evidence, for the first time, that supports a causal relationship between right, but not left, pSTG and auditory-motor integration for vocal pitch regulation. This lends support to a right-lateralized contribution of the pSTG in not only the bottom-up detection of vocal feedback errors but also the involvement of driving motor commands for error correction in a top-down manner.

Continuous theta burst stimulation over left and right supramarginal gyri demonstrates their involvement in auditory feedback control of vocal production.

The supramarginal gyrus (SMG) has been implicated in auditory-motor integration for vocal production. However, whether the SMG is bilaterally or unilaterally involved in auditory feedback control of vocal production in a causal manner remains unclear. The present event-related potential (ERP) study investigated the causal roles of the left and right SMG to auditory-vocal integration using neuronavigated continuous theta burst stimulation (c-TBS). Twenty-four young adults produced sustained vowel phonations and heard their voice unexpectedly pitch-shifted by ±200 cents after receiving active or sham c-TBS over the left or right SMG. As compared to sham stimulation, c-TBS over the left or right SMG led to significantly smaller vocal compensations for pitch perturbations that were accompanied by smaller cortical P2 responses. Moreover, no significant differences were found in the vocal and ERP responses when comparing active c-TBS over the left vs. right SMG. These findings provide neurobehavioral evidence for a causal influence of both the left and right SMG on auditory feedback control of vocal production. Decreased vocal compensations paralleled by reduced P2 responses following c-TBS over the bilateral SMG support their roles for auditory-motor transformation in a bottom-up manner: receiving auditory feedback information and mediating vocal compensations for feedback errors.

Gender and age disparities in small-to-medium arterial stiffness among the Chinese population.

BACKGROUND AND AIMS: Arterial pressure-volume index (API) is a non-invasive tool for assessing small-to-medium-sized arterial stiffness. This study aimed to investigate the potential age- and sex-related differences in the API and explore the practical implications of such differences. METHODS AND RESULTS: The study analysed 7620 subjects for whom API measurements were available. Linear regression and restrictive cubic spline models were used to investigate the associations between potential risk conditions and the API. Additionally, this study employed a backward stepwise regression method to identify the independent factors associated with a high API. Middle-aged to older women had higher API values and a higher prevalence of high API than men in the same age group. However, the opposite was observed among younger individuals, with women having lower API values than men. This study also identified a J-shaped relationship between API and age, where API values began to increase at a certain age and rapidly increased after that. In women, the API started to increase at 31 years of age and rapidly increased after 54 years of age. In men, the API started to increase at 38 years of age, followed by a rapid increase after 53 years of age. CONCLUSION: This study's observation of a significant age-sex interaction in small-to-medium-sized arterial stiffening offers a valuable explanation for cardiovascular disease risk and provides important parameters for using API measurements to evaluate such risk.

A causal link between left supplementary motor area and auditory-motor control of vocal production: Evidence by continuous theta burst stimulation.

The supplementary motor area (SMA) has been implicated in the feedforward control of speech production. Whether this region is involved in speech motor control through auditory feedback, however, remains uncertain. The present event-related potential (ERP) study examined the role of the left SMA in vocal pitch regulation in a causal manner by combining auditory feedback manipulations and neuronavigated continuous theta bust stimulation (c-TBS). After receiving c-TBS over the left SMA or the control site (vertex), twenty young adults vocalized the vowel sound /u/ while hearing their voice unexpectedly pitch-shifted -50 or -200 cents. Compared to the control stimulation, c-TBS over the left SMA led to decreased vocal compensations for pitch perturbations of -50 and -200 cents. A significant decrease of N1 and P2 responses to -200 cents perturbations was also found when comparing active and control stimulation. Major neural generators of decreased P2 responses included the right-lateralized superior and middle temporal gyrus and angular gyrus. Notably, a significant correlation was found between active-control differences in the vocal compensation and P2 responses for the -200 cents perturbations. These findings provide neurobehavioral evidence for a causal link between the left SMA and auditory-motor integration for vocal pitch regulation, suggesting that the left SMA receives auditory feedback information and mediates vocal compensations for feedback errors in a bottom-up manner.

Pyrroloquinoline quinone protects against exercise-induced fatigue and oxidative damage via improving mitochondrial function in mice.

Pyrroloquinoline quinone (PQQ) has a variety of biological functions. However, rare attention has been paid to its effects on exercise-induced damage. Here, we assessed the potential protective effects of PQQ against the fatigue and oxidative damage caused by repeated exhaustive exercise, and studied the underlying mechanism. The models for exercise-induced fatigue were established, and the parameters were measured, including the time to exhaustion (TTE), biochemical indicators, the expression of nuclear factor kappa B (NF-κB) and inflammatory cytokines and so on. Besides, the mitochondrial function was evaluated by the morphology, membrane potential, respiratory function, adenosine triphosphate (ATP) levels, and the application of the mitochondrial complex I inhibitor. The results demonstrate that PQQ prolongs TTE, causes the decrease in the activity of serum creatine kinase and lactate dehydrogenase, increases the activity of antioxidant enzymes, inhibits the production of reactive oxygen species (ROS) and malondialdehyde (MDA), and diminishes the over expression of NF-κB (p65) and inflammatory mediators. Furthermore, PQQ preserves normal mitochondrial function. Particularly, PQQ reduces the accumulation of ROS triggered by the mitochondrial complex I inhibitor. These data suggest that PQQ can significantly protect mice from exercise-induced fatigue and oxidative damage by improving mitochondrial function. These data also suggest that PQQ controls mitochondrial activity through directly affecting the NADH dehydrogenase.

Proposal for Unification of the Genus Metakosakonia and the Genus Phytobacter to a Single Genus Phytobacter and Reclassification of Metakosakonia massiliensis as Phytobacter massiliensis comb. nov.

The genus Metakosakonia, as the closest phylogenetic neighbor of the genus Kosakonia within the family Enterobacteriaceae, when proposed in 2017, consisted of M. massiliensis JC163T and Metakosakonia spp. strains CAV1151 and GT-16. The strain CAV1151 was later classified into a novel species Phytobacter ursingii. Here, we show that the strain GT-16 shares a digital DNA-DNA hybridization (DDH) similarity of 91.0% with P. diazotrophicus DSM 17806 T and thus also belongs to P. diazotrophicus. M. massiliensis and the strains within the genus Phytobacter formed a monophyletic cluster on a phylogenomic tree based on the core proteins of the family Enterobacteriaceae and on a phylogenetic tree based on the 16S rRNA genes. M. massiliensis and the genus Phytobacter share average amino acid identities of 86.80‒87.41% above the threshold (86%) for genus delimitation within the family Enterobacteriaceae. Moreover, they share conserved signature indels in the intracellular growth protein IgaA and the outer membrane assembly protein AsmA. Therefore, we propose to unite the genus Metakosakonia and the genus Phytobacter to a single genus. Because the genus Phytobacter was validly published earlier in 2017 than the genus Metakosakonia in 2017, the genus name Phytobacter has priority over Metakosakonia. We propose to unite the two genera under the name Phytobacter with the type species P. diazotrophicus and reclassify M. massiliensis as P. massiliensis comb. nov. In addition, the analyses of genome relatedness and phylogenomic relationship identified one potential novel species within the genus Phytobacter and three potential novel species within the genus Kosakonia.

Top-Down Modulation of Auditory-Motor Integration during Speech Production: The Role of Working Memory.

Although working memory (WM) is considered as an emergent property of the speech perception and production systems, the role of WM in sensorimotor integration during speech processing is largely unknown. We conducted two event-related potential experiments with female and male young adults to investigate the contribution of WM to the neurobehavioural processing of altered auditory feedback during vocal production. A delayed match-to-sample task that required participants to indicate whether the pitch feedback perturbations they heard during vocalizations in test and sample sequences matched, elicited significantly larger vocal compensations, larger N1 responses in the left middle and superior temporal gyrus, and smaller P2 responses in the left middle and superior temporal gyrus, inferior parietal lobule, somatosensory cortex, right inferior frontal gyrus, and insula compared with a control task that did not require memory retention of the sequence of pitch perturbations. On the other hand, participants who underwent extensive auditory WM training produced suppressed vocal compensations that were correlated with improved auditory WM capacity, and enhanced P2 responses in the left middle frontal gyrus, inferior parietal lobule, right inferior frontal gyrus, and insula that were predicted by pretraining auditory WM capacity. These findings indicate that WM can enhance the perception of voice auditory feedback errors while inhibiting compensatory vocal behavior to prevent voice control from being excessively influenced by auditory feedback. This study provides the first evidence that auditory-motor integration for voice control can be modulated by top-down influences arising from WM, rather than modulated exclusively by bottom-up and automatic processes.SIGNIFICANCE STATEMENT One outstanding question that remains unsolved in speech motor control is how the mismatch between predicted and actual voice auditory feedback is detected and corrected. The present study provides two lines of converging evidence, for the first time, that working memory cannot only enhance the perception of vocal feedback errors but also exert inhibitory control over vocal motor behavior. These findings represent a major advance in our understanding of the top-down modulatory mechanisms that support the detection and correction of prediction-feedback mismatches during sensorimotor control of speech production driven by working memory. Rather than being an exclusively bottom-up and automatic process, auditory-motor integration for voice control can be modulated by top-down influences arising from working memory.

Constructing a MoS2 QDs/CdS Core/Shell Flowerlike Nanosphere Hierarchical Heterostructure for the Enhanced Stability and Photocatalytic Activity.

MoS2 quantum dots (QDs)/CdS core/shell nanospheres with a hierarchical heterostructure have been prepared by a simple microwave hydrothermal method. The as-prepared samples are characterized by XRD, TEM, SEM, UV-VIS diffuse reflectance spectra (DRS) and N2-sorption in detail. The photocatalytic activities of the samples are evaluated by water splitting into hydrogen. Results show that the as-prepared MoS2 QDs/CdS core/shell nanospheres with a diameter of about 300 nm are composed of the shell of CdS nanorods and the core of MoS2 QDs. For the photocatalytic reaction, the samples exhibit a high stability of the photocatalytic activity and a much higher hydrogen evolution rate than the pure CdS, the composite prepared by a physical mixture, and the Pt-loaded CdS sample. In addition, the stability of CdS has also been greatly enhanced. The effect of the reaction time on the formations of nanospheres, the photoelectric properties and the photocatalytic activities of the samples has been investigated. Finally, a possible photocatalytic reaction process has also been proposed.

Atmospheric Vapor Impact on Desert Vegetation and Desert Ecohydrological System.

The ability of plants to absorb unsaturated atmospheric water vapor is a controversial topic. To study how vegetation in arid areas survives under limited water resources, this study uses Tamarisk in the Ulan Buh Desert of China as an example. The in-situ observation of a newly designed Lysimeter and sap flow meter system were used to monitor the precipitation infiltration and the utilization efficiency of Tamarisk of atmospheric vapor. The results show that the annual precipitation of 84 mm in arid areas could still result in deep soil recharge (DSR) with a recharge rate of 5 mm/year. Furthermore, DSR is detectable even in the winter, and the 5-year average DSR was 5.77% of the annual precipitation. It appears that the small precipitation events are critically important for the survival of Tamarisk. When the atmospheric relative humidity reaches 70%, Tamarisk leaves can absorb the unsaturated atmospheric vapor, which accounts for 13.2% of the annual precipitation amount. To adapt to the arid environment, Tamarisk can harvest its water supply from several sources including atmospheric vapor and micro-precipitation events (whose precipitation is below the measurement limit of 0.2 mm of the precipitation gauge) and can still permit a certain amount of recharge to replenish the deep soil moisture. Such an ecohydrological dynamic is of great significance to desert vegetation.

Transcranial direct current stimulation over left dorsolateral prefrontal cortex facilitates auditory-motor integration for vocal pitch regulation.

Background: A growing body of literature has implicated the left dorsolateral prefrontal cortex (DLPFC) in the online monitoring of vocal production through auditory feedback. Specifically, disruption of or damage to the left DLPFC leads to exaggerated compensatory vocal responses to altered auditory feedback. It is conceivable that enhancing the cortical excitability of the left DLPFC may produce inhibitory influences on vocal feedback control by reducing vocal compensations. Methods: We used anodal transcranial direct current stimulation (a-tDCS) to modulate cortical excitability of the left DLPFC and examined its effects on auditory-motor integration for vocal pitch regulation. Seventeen healthy young adults vocalized vowel sounds while hearing their voice pseudo-randomly pitch-shifted by ±50 or ±200 cents, either during (online) or after (offline) receiving active or sham a-tDCS over the left DLPFC. Results: Active a-tDCS over the left DLPFC led to significantly smaller peak magnitudes and shorter peak times of vocal compensations for pitch perturbations than sham stimulation. In addition, this effect was consistent regardless of the timing of a-tDCS (online or offline stimulation) and the size and direction of the pitch perturbation. Conclusion: These findings provide the first causal evidence that a-tDCS over the left DLPFC can facilitate auditory-motor integration for compensatory adjustment to errors in vocal output. Reduced and accelerated vocal compensations caused by a-tDCS over left DLPFC support the hypothesis of a top-down neural mechanism that exerts inhibitory control over vocal motor behavior through auditory feedback.

PEG-PEI/siROCK2 inhibits Aß42-induced microglial inflammation via NLRP3/caspase 1 pathway.

OBJECTIVES: There is an urgent need to develop therapeutic strategies to improve the treatment outcome of Alzheimer's disease. The treatment strategy of gene therapy mediated by nanocarrier systems brings new hope for the treatment of Alzheimer's disease. ROCK2 is involved in various pathological processes of Alzheimer's disease and may be a potential target for the treatment of Alzheimer's disease. Our previous study indicated that PEG-PEI/siROCK2 [polyethyleneglycol-polyethyleneimine deliver ROCK2-siRNA, (PPSR)] prevented Aß42-induced neurotoxicity and showed a promising prospect for the treatment of Alzheimer's disease. However, whether PPSR has an effect on the microglial inflammation in Alzheimer's disease is still unclear. MATERIALS AND METHODS: 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide assay was used to detect the cytotoxicity of PEG-PEI and PPSR in primary microglial cells. Real-time PCR and western blotting were used to assess the expression of ROCK2 and nucleotide oligomerization domain-like receptor family pyrin domain containing 3 (NLRP3)/caspase 1 pathway in primary microglial cells. ELISA assay was used to measure the effect of PPSR on attenuating the lipopolysaccharide (LPS) + Aß-induced increase in IL-1ß. RESULTS: PEG-PEI concentration less than 20 µg/ml and the N/P (molar ratio of PEG-PEI amino/siRNA phosphate) ratio of PPSR less than 50 showed no significant cytotoxicity in primary microglia cells. PPSR could effectively inhibit the expression of ROCK2 in primary microglial cells. A further study revealed that PPSR attenuates the LPS+Aß-induced increase in IL-1ß without affecting cell viability. In addition, we found that PPSR suppressed the Aß-induced NLRP3/caspase 1 pathway in primary microglial cells. CONCLUSION: PPSR inhibits Aß42-induced microglial inflammation via NLRP3/caspase 1 pathway.

Theta burst stimulation over left cerebellum does not modulate auditory feedback control of vocal production.

Background: Accumulating evidence has shown significant contributions of the right cerebellum to auditory-motor integration for vocal production. Whether the left cerebellum is likewise involved in vocal motor control, however, remains unclear. Methods: By applying neuronavigated continuous and intermittent theta burst stimulation (cTBS/iTBS) over the left cerebellar lobule VII (Crus I), the present event-related potential (ERP) study investigated whether the left cerebellum exerts causal effects in modulating auditory feedback control of vocal pitch production. After receiving cTBS, iTBS, or sham stimulation over the left cerebellum, a group of fifteen young adults produced sustained vowels while hearing their voice unexpectedly shifted in pitch upwards or downwards by 200 cents. The effects of cerebellar stimulation were assessed by measuring the vocal and ERP (N1/P2) responses to pitch perturbations across the conditions. Results: When compared to sham stimulation, cTBS or iTBS over the left cerebellar lobule VII (Crus I) led to no systematic changes in vocal compensations for pitch perturbations in auditory feedback. Also, the cortical N1/P2 responses did not vary significantly across the three stimulation sessions. Conclusion: These findings present the first neurobehavioral evidence suggesting that the left cerebellum is not causally associated with auditory feedback control of vocal production. Together with previously reported causal effects of the right cerebellum in modulating vocal pitch regulation, the present study lends support to the hypothesis that there is a functional lateralization of the cerebellum in vocal motor control though auditory feedback.

Spatiotemporal tradeoffs and synergies in vegetation vitality and poverty transition in rocky desertification area.

Vegetation recovery and poverty alleviation are critical problems in the karst national designed poor counties (NPDC) in southwest China. However, little information is available about the relationship between poverty and vegetation dynamics in these areas. In this study, we used remote sensing and statistical datasets from 2000 to 2015 to identify the relations between vegetation dynamics and poverty among the NPDC in southwest rocky desertification areas. We estimated the vegetation dynamics using the Normalized Difference Vegetation Index and poverty with the rural per capita net income. Local indicator of spatial association and the space-time transition type of poverty were applied to identify spatial patterns of the poverty spatial distribution relationship and transition. Also, poverty, natural and ecological governance factors were assessed using the Geo-detector method to uncover the driving factors of karst vegetation. The results showed that vegetation increased significantly (p < 0.05) in karst NPDC (82.82%) and rocky desertification control counties (78.77%). The karst NPDC was significantly clustered. The hot spots of rural per capita net income changed from west and north (2000) to only north (2015) and cold spots changed from east and south (2000) to only south (2015). The rural per capita net income spatiotemporal transition was higher in 2000 than in 2015. We found a weak synergy between vegetation change and poverty type transition in 42.86% of the browning counties, 45.45% in the slowly greening counties, and 43.65% in stable greening counties. However, 57.50% of counties in the quick greening counties showed a tradeoff relationship with the poverty type transition. The rocky desertification rate and ecological engineering measures affected vegetation dynamics importantly. The results will help decision-makers to understand the interdependence between vegetation and poverty. This will contribute to better policies formulation to tackle poverty in the karst rocky desertification area.

Proposal for reunification of the genus Raoultella with the genus Klebsiella and reclassification of Raoultella electrica as Klebsiella electrica comb. nov.

The order Enterobacterales was divided into seven families including the family Enterobacteriaceae in 2016. The genus Klebsiella within the family Enterobacteriaceae was divided into two genera Klebsiella and Raoultella in 2001. Here, our phylogenomic analysis shows that the genus Raoultella is nested within the genus Klebsiella. Klebsiella and Raoultella together are monophyletic and share average amino acid identities (AAIs) of 86.9-89.6% above the AAI threshold (86%) for genus delimitation within the family Enterobacteriaceae. Klebsiella and Raoultella share AAIs of 79.9%-85.0% with the other genera within the subfamily "Klebsiella clade", which are in the range of inter-genus AAIs (74-85%) within the family Enterobacteriaceae. Klebsiella and Raoultella also share six known conserved signature indels. Therefore, we propose to reunify Klebsiella and Raoultella to the single genus Klebsiella and reclassify Raoultella electrica as Klebsiella electrica comb. nov. Our genome-based taxonomic analyses also identified seven potential novel species within the unified genus Klebsiella.

Event-related potential correlates of auditory feedback control of vocal production in experienced singers.

Considerable evidence has shown that experienced singers are capable of voluntarily suppressing vocal compensations for consistent pitch perturbations in auditory feedback. Our recent behavioral study found that singers also compensated for brief pitch perturbations to a lesser degree than nonsingers in an involuntary manner. In the present event-related potential study, we investigated the neural correlates of involuntary vocal pitch regulation in experienced singers. All participants were instructed to vocalize the vowel sounds while their voice was unexpectedly shifted in pitch by -50 and -200 cents. The results revealed decreased cortical N1 and P2 responses to pitch perturbations and reduced involuntary vocal compensations for singers when compared to nonsingers. Moreover, larger vocal responses were significantly correlated with smaller cortical P2 responses for nonsingers, whereas this brain-behavior relationship did not exist for singers. These findings demonstrate that the cortical processing of involuntary auditory-motor integration for vocal pitch regulation can be shaped as a function of singing experience, suggesting that experienced singers may be less influenced by auditory feedback and rely more on somatosensory feedback or feedforward control as a consequence of singing training as compared to nonsingers.

Carrying capacity for vegetation across northern China drylands.

Revegetation and afforestation across drylands for establishing sustainable ecosystems requires a comprehensive understanding of the carrying capacity for vegetation (CCV) at the regional scale. To determine the CCV across drylands in northern China, we developed a technical framework based on two measures of leaf area index (LAI): maximum LAI (Max-LAI) and safe LAI (Safe-LAI), and their thresholds, CCVmax and CCVsafe, for six drylands (Horqin, Hulun Buir, Otindag, Mu Us, Tengger, and Junggar) using remote sensing datasets from 2000 to 2014. We also predicted dynamics of CCV of the drylands over the next decade (2015-2024) by establishing optimal prediction models based on environmental factors (temperature, precipitation, potential evapotranspiration, and elevation). According to these models, the Max-LAI threshold (range: 0.36-1.03 m2/m2) and Safe-LAI threshold (0.29-0.70 m2/m2) declined from east to west with decreases in aridity index. Under current climatic variability and anthropogenic disturbances, the CCV in most drylands would have positive increments (approximately 15%), except in the Horqin (approximately -15%) and Tengger (slight changes), during the following decade. This indicates that there is scope for improving vegetation coverage in most drylands, except in the Horqin and Tengger. Our results suggest that revegetation and ecosystem management to prevent ongoing desertification should be carried out at the regional scale. Although it does not account for biocrusts, artificially introduced vegetation, underground water, and other vegetation attributes (e.g., density and biomass), our technical framework and results might nonetheless be valuable in evaluating regional ecological security and guiding vegetation restoration of drylands across northern China.

Natural stable isotope ratios and fatty acid profiles of estuarine tidal flat nematodes reveal very limited niche overlap among co-occurring species.

The high local-scale species diversity of marine meiofauna, and of nematodes in particular, has puzzled ecologists for decades. Both pronounced niche differentiation and neutral dynamics have been suggested as mechanisms underlying that high diversity. Differential resource use is the most plausible basis for niche differentiation, yet the vast majority of studies demonstrating that this is prominent in marine nematodes are based on laboratory experiments on single species or highly simplified assemblages. Only a small number of studies have investigated resource differentiation under natural conditions. Here we use natural stable-isotope ratios of carbon and nitrogen, as well as fatty-acid profiles, to assess differential resource use and trophic structure in nine abundant estuarine tidal flat nematode species, comprising different presumed feeding modes (deposit feeders, epistratum feeders, predators) and resource guilds (herbivores, carnivores) based on buccal cavity morphology. Nematodes comprise up to three different trophic levels (from primary to tertiary consumers), yet with the exception of some herbivores, omnivory is prominent. Bivariate isotopic niche spaces were of similar size among most species, irrespective of their trophic level. Herbivory not only contributed importantly to the nutrition of suspected herbivores, but also to that of species that were previously considered carnivores based on the morphology of their buccal cavity. Herbivory mainly targets diatoms in some nematode species, yet includes dinoflagellates in others. Bacteria, in contrast, appear to be of limited nutritional importance. Odontophora setosus is identified as a predator/omnivore (possibly of heterotrophic protists) with a trophic level in between that of secondary and tertiary consumers. Our study thus demonstrates that resource differentiation is pronounced among as well as within nematode feeding modes and resource guilds. However, this study included only the most abundant species of the in situ community, hence it remains to be established whether and to what extent its conclusions can be extrapolated to entire, often highly species-rich communities.

Analysis of Urban-Rural Land-Use Change during 1995-2006 and Its Policy Dimensional Driving Forces in Chongqing, China.

This paper analyzes the urban-rural land-use change of Chongqing and its policydimensional driving forces from 1995 to 2006, using high-resolution Landsat TM(Thematic Mapper) data of 1995, 2000 and 2006, and socio-economic data from bothresearch institutes and government departments. The outcomes indicated that urban-ruralland-use change in Chongqing can be characterized by two major trends: First, thenon-agricultural land increased substantially from 1995 to 2006, thus causing agriculturalland especially farmland to decrease continuously. Second, the aggregation index of urbansettlements and rural settlements shows that local urban-rural development experienced aprocess of changing from aggregation (1995-2000) to decentralization (2000-2006).Chongqing is a special area getting immersed in many important policies, which includethe establishment of the municipality directly under the Central Government, the buildingof Three Gorges Dam Project, the Western China Development Program and theGrain-for-Green Programme, and bring about tremendous influences on its land-usechange. By analyzing Chongqing's land-use change and its policy driving forces, someimplications for its new policy of 'Urban-rural Integrated Reform' are obtained. That ismore attentions need to be paid to curbing excessive and idle rural housing andconsolidating rural construction land, and to laying out a scientific land-use plan for its rural areas taking such rural land-use issues as farmland occupation and rural housing landmanagement into accounts, so as to coordinate and balance the urban-rural development.

Publisher Correction: A Co3O4-CDots-C3N4 three component electrocatalyst design concept for efficient and tunable CO2 reduction to syngas.

The original HTML version of this Article omitted to list Yeshayahu Lifshitz as a corresponding author and incorrectly listed Shuit-Tong Lee as a corresponding author.Correspondingly, the original PDF version of this Article incorrectly stated that "Correspondence and requests for materials should be addressed to X.J. (email: xin.jiang@uni-siegen.de), or to Y.L. (email: yangl@suda.edu.cn), or to S.-T.L. (email: shayli@technion.ac.il), or to Z.K. (email: zhkang@suda.edu.cn)", instead of the correct "Correspondence and requests for materials should be addressed to X.J. (email: xin.jiang@uni-siegen.de), or to Y. Liu (email: yangl@suda.edu.cn), or to Y. Lifshitz (email: shayli@technion.ac.il), or to Z.K. (email: zhkang@suda.edu.cn)".This has now been corrected in the PDF and HTML versions of the Article.