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Though implementing feedback provided by peers has been an essential step for learning efficiency in peer feedback activities, it remains challenging for students. This study aims to explore the inner structure patterns of students' peer feedback and how they are related to feedback implementation. Sixty-nine engineering students from a Singapore university participated in the peer feedback activity. Content analysis was conducted to analyse the inner structure of feedback as well as the implementation status of each feedback. Sequential mining was applied to investigate the sequential patterns of the various feedback components. The results show a variation of inner structures in the implemented feedback and unimplemented feedback. The implemented feedback tended to be sequenced with an evaluation or a standpoint before seeking clarification or suggestions for improvement. It was also likely to contain continuous questions seeking clarifications. In comparison, the unimplemented feedback was likely to continuously indicate positive evaluations or agreements. By understanding the inner structure of peer feedback with different implementation statuses, researchers and educators can fine-tune design and instructions to support peer feedback practices. [ABSTRACT FROM AUTHOR]

Lead‐free double perovskites with multi‐mode emission characters are highly desired for optoelectronic devices. Herein, dual‐mode thermal responses with low thermal quenching in the red emission channel and high thermal quenching in the near‐infrared (NIR) channel are achieved in a holmium‐based double perovskite (Cs2NaHoCl6). The temperature‐dependent emission is modulated by manipulating three cross relaxations of CR1 (5F4, 5I7) → (5F5, 5I6), CR2 (5S2, 5I8) → (5F5, 5I7), and CR3 (5F5, 5F5) → (5I7, 5G4) through adjusting the concentration of Ho3+. The difference in thermal response between the red and NIR emissions becomes more pronounced with a higher concentration of Ho3+ up to 100%, while the two emissions show almost the same thermal quenching behavior when the Ho3+ concentration is below 20%. To demonstrate their applications, a thermal‐responsive dual‐mode information encryption system and a NIR emitting LED with night vision capacity are fabricated using the prepared samples. This study provides a new approach for thermal quenching regulation in rare‐earth‐based lead‐free perovskites and illustrates their potential in lighting, anti‐counterfeiting, and sensing applications. [ABSTRACT FROM AUTHOR]

Nurturing twenty-first-century competency is one important agenda in this era, especially in developing collaborative learning and critical thinking skills. Yet, facilitating such a computer-supported collaborative learning (CSCL) environment is challenging. Although several technological platforms from past research studies were developed to support collaborative learning, having a system that comprises a collaboration script, and graph-based workspaces to facilitate explicit externalization of cognitive processes, at the same time, armed with learning analytics to monitor the collaboration and cognitive processes is rare. In this paper, the AppleTree system is presented to illustrate three unique features. Firstly, the AppleTree system is designed with a graph-based workspace to facilitate explicit externalization of knowledge co-constructions and argumentation. Secondly, the system is embedded with a four-phased switch to structure the CSCL process. Thirdly, the system possesses real-time learning analytics, including contribution counts, social network analysis, and the learning artifacts' argumentation structure to promote the development of arguments. An exploratory case study was conducted to examine the design of the AppleTree system in an authentic classroom. Empirical findings showed that the AppleTree system helped regulate effective collaboration and supported learners in developing strong arguments. These results could address the social participation and interaction issues related to collaborative learning and enable the development of students' argumentation skills. The implications of the study to educational technology and the CSCL research field are discussed. [ABSTRACT FROM AUTHOR]

This paper investigates data‐driven control for a class of networked control systems with multiple packet dropouts and unknown system parameters. Here, multiple packet dropouts occur randomly in the controller‐to‐actuator (C/A) and sensor‐to‐controller (S/C) channels, where successive packet dropouts are limited by known upper bounds. By introducing the summation inequality, a model‐based mean‐square asymptotic stability condition is established for the closed‐loop networked control system with the potential to migrate to a data‐driven solution. Then, the data‐driven mean‐square asymptotic stability condition for the closed‐loop system is presented by merging the model‐based stability condition with noisy data‐parameterized representations. On this basis, the data‐driven controller gain design approaches for combining unknown and known input gain matrices are presented in turn. Finally, two simulation examples are provided to show the applicability of the developed approaches. [ABSTRACT FROM AUTHOR]

The brain has many connections with various organs. Recent advances have demonstrated the existence of a bidirectional central nervous system (CNS) and intestinal tract, that is, the brain-gut axis. Although studies have suggested that the brain and lung can communicate with each other through many pathways, whether there is a brain–lung axis remains still unknown. Based on previous findings, we put forward a hypothesis: there is a cross-talk between the central nervous system and the lung via neuroanatomical pathway, endocrine pathway, immune pathway, metabolites and microorganism pathway, gas pathway, that is, the brain–lung axis. Beyond the regulation of the physiological state in the body, bi-directional communication between the lung and the brain is associated with a variety of disease states, including lung diseases and CNS diseases. Exploring the brain–lung axis not only helps us to understand the development of the disease from different aspects, but also provides an important target for treatment strategies. [ABSTRACT FROM AUTHOR]

The issue of adaptive tracking control for nonlinear uncertain system with self-triggered input and immeasurable states is investigated. The Radial Basis Function of Neural Networks (RBFNNs) is introduced to approximate unknown nonlinear functions. Based on this, an observer is constructed to estimate the immeasurable states. Considering that the self-triggered input may cause poor tracking performance, the prescribed performance bound method is combined into co-designing. Furthermore, a self-triggered adaptive control scheme is presented to guarantee close-loop system signals are bounded. Compared with the event-triggered scheme, the presented self-triggered scheme can compute the next trigger point through the current one. It is not required to continuously monitor the measurement error to determine whether the triggering condition is reached. By the given control scheme, the tracking error can be bounded in prescribing performance bounds, and reaches the balance of network resource saving and tracking performance. These are verified by the given simulation example. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRNAs) are important post‐transcriptional regulators of gene expression and play key roles in many biological processes, such as development and response to multiple stresses. However, little is known about their roles in generating novel phenotypes and phenotypic variation during the course of animal evolution. Here, we, for the first time, characterized the miRNAs of the cochlea in an echolocating bat (Rhinolophus affinis). We sampled eight individuals from two R. affinis subspecies with significant echolocation call frequency differences. We identified 365 miRNAs and 121 of them were novel. By searching sequences of these miRNAs precursors in multiple high‐quality mammal genomes, we found one specific miRNA shared by all echolocating bats but not present in all other nonecholocating mammals. The targeted genes of this miRNA included several known hearing genes (e.g., KCNQ4 and GJB6). Together with the matched mRNA‐seq data, we identified 1766 differentially expressed genes (DEGs) between the two subspecies and 555 of them were negatively regulated by differentially expressed miRNAs (DEMs). We found that almost half of known hearing genes in the list of all DEGs were regulated negatively by DEMs, suggesting an important role of miRNAs in call frequency variation of the two subspecies. These targeted DEGs included several important hearing genes (e.g., Piezo1, Piezo2, and CDH23) that have been shown to be important in ultrasonic hearing of echolocating mammals. [ABSTRACT FROM AUTHOR]

Seasonality can cause changes in many environmental factors which potentially affects gene expression. Here, we used a bat species (Rhinolophus sinicus) from eastern China as a model to explore the molecular mechanisms of seasonal effects, in particular during phenological shifts in the spring and autumn. Based on the analysis of 45 RNA‐seq samples, we found strong seasonal effects on gene expression, with a large number of genes identified as either specific or biased to each season. Weighted gene co‐expression network analysis also identified multiple modules significantly associated with each season. These seasonal genes were further enriched into different functional categories. Consistent with effects of phenological shifts on bats, we found that genes related to promoting food intake were highly expressed in both autumn and spring. In addition, immunity genes were also highly expressed in both seasons although this seasonal immune response had tissue specificity in different seasons. In female bats, genes related to the delay of ovulation (e.g., NPPC, natriuretic peptide precursor type C) were highly expressed in October, while genes associated with the promotion of reproduction (e.g., DIO2, iodothyronine deiodinase 2) were biasedly expressed in April. Lastly, we found multiple known core clock genes in both October‐biased and April‐biased expressed genes, which may be involved in regulating the start and end of hibernation, respectively. Overall, together with studies in other land and aquatic animals, our work supports that seasonal gene expression variations may be a general evolutionary response to environmental changes in wild animals. [ABSTRACT FROM AUTHOR]

We experimentally investigate the characteristics of a dynamic wake and of flow separation for a square cylinder with steady suction at its leading-edge corners. The wind tunnel experiments were conducted at a Reynolds number of 5946, and suction slots were manufactured symmetrically at the leading corners of the square cylinder. Steady suction was characterized with a suction momentum coefficient C μ varying from 0.0227 to 0.3182. A time-resolved particle image velocimetry system was used to evaluate the control of leading-edge suction at different C μ . Next, the measurements were analyzed by applying a proper orthogonal decomposition (POD) to study the control effectiveness. The POD results suggest that the first four modes of wake vortex shedding are transformed in controlled cases and that periodic Karman vortex shedding is suppressed. The results also show that, even with a very small momentum coefficient, the steady suction at the leading-edge corners stabilizes the cylinder wake. The wake region becomes longer and narrower in comparison with the baseline case. In addition, modifications of separation flow were visualized. At quite small C μ , flow separation at the leading-edge corners is considerably suppressed. Upon increasing the suction momentum coefficient to 0.1364, flow separation at the leading edges is almost eliminated. Finally, we estimate the effect of drag reduction due to the leading-edge suction. [ABSTRACT FROM AUTHOR]

This article is concerned with the issue of event‐triggered based adaptive tracking control for a class of nonlinear uncertain system with input hysteresis. The radial basis function of neural networks (RBFNNs) is utilized to compensate the uncertain parts, where approximation errors are combined into the approximation system. Then, consider such method may extend the developed the weight vector of RBFNNs' dimension, such that computing burdens are increased while the considered system is subjected to network resource constraint. Thus, an adaptive neural event‐triggered scheme is designed. Furthermore, aiming to compensate the hysteresis effect, an auxiliary system is incorporated into the control design process. In virtue of backstepping technique, an adaptive neural event‐triggered control approach is determined for the considered system, such that all close‐loop system signals boundedness is remaining bounded. Theoretical results are verified through the given simulation cases. [ABSTRACT FROM AUTHOR]

Background: Mitochondrial function involves the interplay between mitochondrial and nuclear genomes. Such mitonuclear interactions can be disrupted by the introgression of mitochondrial DNA between taxa or divergent populations. Previous studies of several model systems (e.g. Drosophila) indicate that the disruption of mitonuclear interactions, termed mitonuclear mismatch, can alter nuclear gene expression, yet few studies have focused on natural populations. Results: Here we study a naturally introgressed population in the secondary contact zone of two subspecies of the intermediate horseshoe bat (Rhinolophus affinis), in which individuals possess either mitonuclear matched or mismatched genotypes. We generated transcriptome data for six tissue types from five mitonuclear matched and five mismatched individuals. Our results revealed strong tissue-specific effects of mitonuclear mismatch on nuclear gene expression with the largest effect seen in pectoral muscle. Moreover, consistent with the hypothesis that genes associated with the response to oxidative stress may be upregulated in mitonuclear mismatched individuals, we identified several such gene candidates, including DNASE1L3, GPx3 and HSPB6 in muscle, and ISG15 and IFI6 in heart. Conclusion: Our study reveals how mitonuclear mismatch arising from introgression in natural populations is likely to have fitness consequences. Underlying the processes that maintain mitonuclear discordance is a step forward to understand the role of mitonuclear interactions in population divergence and speciation. [ABSTRACT FROM AUTHOR]

Mitochondrial function needs strong interactions of mitochondrial and nuclear (mitonuclear) genomes, which can be disrupted by mitonuclear mismatch due to mitochondrial DNA (mtDNA) introgression between two formerly isolated populations or taxa. This mitonuclear disruption may cause severe cellular stress in mismatched individuals. Gene expression changes and alternative splicing (AS) are two important transcriptional regulations to respond to environmental or cellular stresses. We previously identified a naturally introgressed population in the intermediate horseshoe bat (Rhinolophus affinis). Individuals from this population belong to R. a. himalayanus and share almost identical nuclear genetic background; however, some of them had mtDNA from another subspecies (R. a. macrurus). With this unique natural system, we examined gene expression changes in six tissues between five mitonuclear mismatched and five matched individuals. A small number of differentially expressed genes (DEGs) were identified, and functional enrichment analysis revealed that most DEGs were related to immune response although some may be involved in response to oxidative stress. In contrast, we identified extensive AS events and alternatively spliced genes (ASGs) between mismatched and matched individuals. Functional enrichment analysis revealed that multiple ASGs were directly or indirectly associated with energy production in mitochondria which is vital for survival of organism. To our knowledge, this is the first study to examine the role of AS in responding to cellular stress caused by mitonuclear mismatch in natural populations. Our results suggest that AS may play a more important role than gene expression regulation in responding to severe environmental or cellular stresses. [ABSTRACT FROM AUTHOR]

The presence of the blood-brain barrier (BBB) remains a challenge in the treatment of central nervous system (CNS) diseases, as it hinders the infiltration of many therapeutic drugs into the brain parenchyma. Therefore, developing efficacious pharmacological agents that can traverse the BBB is crucial for optimal treatment of diseases of the CNS such as neurodegenerative conditions and brain tumors. Adeno-associated virus (AAV), one of the most promising gene therapy vectors, has been shown to cross the BBB safely and is non-pathogenic in nature and therefore has been utilized for numerous diseases of the CNS. Along with the development of protein engineering techniques such as directed evolution including DNA shuffling, a great number of BBB-crossing AAVs have been developed, that could be systemically injected for therapeutic benefit. In this review, we discuss several feasible approaches to improve transportation of therapeutic agents to the CNS. We also discuss the advantages of using BBB-crossing AAVs, their role as a gene delivery agent and highlight the different types of BBB-AAV vectors that have been developed in order to provide a greater insight into how they can be used in diseases of the CNS. [Display omitted] • BBB structure and the BBB-crossing strategies • AAV biology and BBB-crossing ability • Developing BBB-crossing ability enhanced AAV variants [ABSTRACT FROM AUTHOR]

Glioblastoma (GBM) is the most common and malignant Grade IV primary craniocerebral tumor caused by glial cell carcinogenesis with an extremely poor median survival of 12–18 months. The current standard treatments for GBM, including surgical resection followed by chemotherapy and radiotherapy, fail to substantially prolong survival outcomes. Adeno-associated virus (AAV)-mediated gene therapy has recently attracted considerable interest because of its relatively low cytotoxicity, poor immunogenicity, broad tissue tropism, and long-term stable transgene expression. Furthermore, a range of gene therapy trials using AAV as vehicles are being investigated to thwart deadly GBM in mice models. At present, AAV is delivered to the brain by local injection, intracerebroventricular (ICV) injection, or systematic injection to treat experimental GBM mice model. In this review, we summarized the experimental trials of AAV-based gene therapy as GBM treatment and compared the advantages and disadvantages of different AAV injection approaches. We systematically introduced the prospect of the systematic injection of AAV as an approach for AAV-based gene therapy for GBM. [ABSTRACT FROM AUTHOR]

Recently diverged taxa with contrasting phenotypes offer opportunities for unravelling the genetic basis of phenotypic variation in nature. Horseshoe bats are a speciose group that exhibit a derived form of high-duty cycle echolocation in which the inner ear is finely tuned to echoes of the narrowband call frequency. Here, by focusing on three recently diverged subspecies of the intermediate horseshoe bat (Rhinolophus affinis) that display divergent echolocation call frequencies, we aim to identify candidate loci putatively involved in hearing frequency variation. We used de novo transcriptome sequencing of two mainland taxa (himalayanus and macrurus) and one island taxon (hainanus) to compare expression profiles of thousands of genes. By comparing taxa with divergent call frequencies (around 15 kHz difference), we identified 252 differentially expressed genes, of which six have been shown to be involved in hearing or deafness in human/mouse. To obtain further validation of these results, we applied quantitative reverse transcription–PCR to the candidate gene FBXL15 and found a broad association between the level of expression and call frequency across taxa. The genes identified here represent strong candidate loci associated with hearing frequency variation in bats. [ABSTRACT FROM AUTHOR]

Summary: In this article, the issue of developing an adaptive event‐triggered neural control for nonlinear uncertain system with input delay is investigated. The radial basis function neural networks (RBFNNs) are adopted to approximate the uncertain terms, where the time‐varying approximation errors are considered into the approximation system. However, the RBFNNs' weight vector is extended, which may cause the computing burdens. To save network resource, the computing burden caused by the weight vector is handled with the developed adaptive control strategy. Furthermore, in order to compensate the effect of input delay, an auxiliary system is introduced into codesign. With the help of adaptive backstepping technique, an adaptive event‐triggered control approach is established. Under the proposed control approach, the effect of input delay can be compensated effectively while the considered system suffered network resource constraint, and all signals in the close‐loop system can be guarantee bounded. Finally, two simulation examples are given to verify the proposed control method's effectiveness. [ABSTRACT FROM AUTHOR]

Multi-stage fractured horizontal well technology is an effective development method for unconventional reservoirs; however, shale oil reservoirs with ultra-low permeability and micro/nanopore sizes are still not ideal for production and development. Injecting CO2 into the reservoir, after hydraulic fracturing, gas injection flooding often produces a gas channeling phenomenon, which affects the production of shale oil. In comparison, CO2 huff-n-puff development has become a superior method in the development of multi-stage fractured horizontal wells in shale reservoirs. CO2 huff and injection can not only improve shale oil recovery but also store the CO2 generated in industrial production in shale reservoirs, which can reduce greenhouse gas emissions to a certain extent and achieve carbon capture, utilization, and storage (CCUS). In this paper, the critical temperature and critical parameters of fluid in shale reservoirs are corrected by the critical point correction method in this paper, and the influence of reservoir pore radius on fluid phase behavior and shale oil production is analyzed. According to the shale reservoir applied in isolation to the actual state of the reservoir and under the condition of a complex network structure, we described the seepage characteristics of shale oil and gas and CO2 in the reservoir by embedding a discrete fracture technology structure and fracture network, and we established the numerical model of the CO2 huff-n-huff development of multi-stage fractured horizontal wells for shale oil. We used the actual production data of the field for historical fitting to verify the validity of the model. On this basis, CO2 huff-n-puff development under different gas injection rates, huff-n-puff cycles, soaking times, and other factors was simulated; cumulative oil production and CO2 storage were compared; and the influence of each factor on development and storage was analyzed, which provided theoretical basis and specific ideas for the optimization of oilfield development modes and the study of CO2 storage. [ABSTRACT FROM AUTHOR]

Collaboration skill is one of the most critical skill sets for engineers-to-be while university engineering students have challenges engaging in productive collaborative learning practices. This study examined the effect of individual preparation before collaboration on students' collaborative learning outcomes and processes. A total of 82 engineering undergraduates (41 pairs) participated in the study and collaborated under two conditions: immediate collaboration and individual preparation before collaboration. A mixed-method approach was applied in this study. Students' online-design solutions and verbal discussions were collected for both collaborative learning outcomes and process analyses. Students produced higher quality design solutions with individual preparation before collaboration than immediate collaboration. There were different engineering design behavioral patterns under the two conditions, indicating different ways to define the design problem, generate solutions, and analyze and evaluate solutions. The findings and discussion provide insights for innovating pedagogical design to promote collaborative learning efficiency in real-world university classrooms. • Students performed better when they started collaboration with individual preparation. • An individual preparation activity mediated how students solved the design problem. • Students worked more like expert engineers with individual preparation than without. • Students are suggested to devote some collaboration time for individual preparation. [ABSTRACT FROM AUTHOR]

An experimental study was conducted to investigate the dynamic ice accretion processes on bridge cables with different surface modifications (i.e., 1. Standard plain, 2. Pattern-indented surface, and 3. Helical fillets). An Icing Research Tunnel available at Iowa State University (i.e., ISU-IRT) was used to generate two typical icing conditions (i.e., dry rime icing vs. wet glaze icing). During the experiments, while a high-speed imaging system was used to capture the transient behaviors of surface water transport and dynamic ice accretion processes over the surfaces of the cable models, a high-accuracy force measurement system was utilized to quantify the dynamic aerodynamic loadings acting on the cable models under different icing conditions. It was found that the addition of surface features (i.e., pattern-indented surface and helical fillets) could dramatically influence the dynamic ice accretion process and the final topology of the ice structures accreted on the cable surfaces. While the ice accretion on the standard plain cable and the cable with helical fillets was found to reduce the drag forces by about 25%, the ice accretion on the pattern-indented cable model would induce about 30% greater aerodynamic drag force acting on the cable model. • Transient details of the icing processes on different bridge cable models were revealed. • Effects of different surface modifications on the ice accretion process were evaluated. • The drag force evolution of bridge cables during icing process were examined. [ABSTRACT FROM AUTHOR]

Abstract As a superior p-type wide bandgap semiconductor, β-CuSCN has a huge potential in optoelectronic device application, and however its conduction could intensively be affected by externally applied bias. Here, we demonstrate electrodeposited individual β-CuSCN trigonal micro/nanopyramids and their array films can show Cu+ trap-controlled bias dependence of electron transport. Before being subjected to a large reverse bias or a unidirectional bias, their cyclic I V curves are coincident resulted from bulk-trap related carrier hopping. At relatively large bidirectional operation bias, they can symmetrically present two large hysteresis loops with negative differential resistance (NDR), and meanwhile accompany with nonvolatile negative resistive switching (RS) feature. After being applied respectively a relatively large fixed bias in two opposite directions, more importantly, switchable classic asymmetrical bipolar RS can successfully be realized at a relatively low operation bias. The switchable formation of reversion and depletion layer, resulted from the minority carriers (electrons) injection into the traps of surface connected with negative electrode, plays a crucial role. Under relatively large bias, the synergistic effect of two surface trap-related back-to-back connected bipolar RS devices results in symmetrical negative RS with NDR. After being applied a relatively large fixed bias, the bipolar RS effect can be enhanced at the surface connected with negative electrode due to the presence of electron injection induced high and narrow barrier, and conversely it disappears at the surface connected with positive electrode due to hole injection-induced ohmic contact. Then, the devices can be set and reset by the filling and emptying of holes in the thin reversion and depletion layer at low reverse and forward voltages, respectively, showing switchable bipolar RS behavior. Due to superior stability, reversibility, nondestructive readout, and low operation bias as well as remarkable cycle performance, the bias-governed conduction with negative RS and switchable bipolar RS makes it a potential candidate in next-generation erasable nonvolatile RRAM devices. Graphical abstract Individual β-CuSCN trigonal micro/nanopyramids and their array films can show Cu+ trap-controlled bias dependence of conduction. Before, under and after applying a large bias, they can show the behaviour of bulk-trap related carrier hopping, symmetrical nonvolatile negative RS characteristics with NDR, and switchable bipolar RS, respectively. The switchable formation of electron injection-induced reversion and depletion layer plays a crucial role at the surface connected with negative electrode. Unlabelled Image Highlights • Individual β-CuSCN micro/nanopyramids and their array films can show bias dependence of electron transport characteristics. • Before being subjected to a large reverse bias or at a unidirectional bias, their cyclic I-V curves are coincident. • Two symmetrical hysteresis loops with negative differential resistance only appear at large bidirectional operation bias. • Switchable bipolar resistive switching is realized after applying large fixed bias in two opposite directions, respectively. • Negative resistive switching can controllably be set and reset by large reverse and forward bias voltage, respectively. [ABSTRACT FROM AUTHOR]

Glioblastoma multiforme (GBM) is the most common type of primary brain tumour in adults, and presents a very low survival rate. Isocitrate dehydrogenase (IDH)1/2 mutations have been found in ~12% of glioblastomas and are associated with long-term GBM survival. However, the risk factors that influence the prognosis of IDH-wild type GBM remain unclear. Hypoxia-inducible factor (HIF)-1α, an important oxygen-regulated transcription factor, has been demonstrated to serve a crucial role in tumour development and to be associated with a poor prognosis. In addition, caveolin-1 (CAV1) is a plasma membrane organizing protein, the expression of which can also be regulated by a hypoxic microenvironment. The present study therefore aimed to examine the expression levels of HIF-1α and CAV1, and their association with GBM prognosis. Reverse transcription-quantitative polymerase chain reaction and western blotting were performed to analyse the expression levels of HIF-1α and CAV1 in paired GBM tumour and adjacent non-tumour tissues. Immunohistochemistry was used to analyse the expression of the two proteins in paraffin-embedded tissues obtained from 42 patients with IDH-wild type GBM. Statistical analyses were performed to examine the correlation between HIF-1α and CAV1 expression and patient prognosis. The results revealed hat the expression levels of HIF-1α and CAV1 were upregulated in IDH-wild type GBM tissues compared to their paired non-tumour tissues (P<0.001). The expression of CAV1 was significantly correlated with high HIF-1α expression (P<0.01). In addition, overexpression of HIF-1α and CAV1 was markedly associated with a poor prognosis (P<0.001). In conclusion, HIF-1α and CAV1 may represent potential biomarkers for IDH-wild type GBM prognosis and potential targets for the development of therapies extending GBM survival. [ABSTRACT FROM AUTHOR]

Objective MicroRNAs (miRNAs) are a class of small noncoding RNAs that play important roles in tumor development and progression. miR-20a acts as an oncogene in many cancers; however, the underlying role of miR-20a in human glioma remains unknown. Methods Glioma tissue samples were obtained from 32 patients with primary glioma who had undergone surgery at the First Affiliated Hospital of Sun Yat-sen University (Guangzhou, China). Twenty-two normal brain tissue samples used as controls were obtained by internal decompression in patients who had undergone surgery for cerebral injury and cerebral hemorrhage at the same hospital. Results Quantitative reverse transcription polymerase chain reaction showed upregulation of miR-20a in glioma tissues and cell lines compared with normal brain tissue and normal human astrocytes. Functional assays showed that miR-20a promotes proliferation and invasion and inhibits apoptosis in glioma cells. The bioinformatic analysis showed that CELF2 (CUGBP Elav-like family member 2) is a direct target gene of miR-20a, which was confirmed using a luciferase reporter assay. Downregulation of CELF2 reversed the effects of inhibiting miR-20a expression. Conclusions Collectively, these results suggest a critical role for miR-20a in glioma cell apoptosis, proliferation, and invasion via the direct targeting of CELF2 and indicate its potential application in cancer therapy. Highlights • miR-20a is upregulated in glioma tissues and cell lines. • miR-20a promotes proliferation and invasion and inhibits apoptosis in glioma cells. • miR-20a affected glioma cell growth by targeting CELF2. • Downregulation of CELF2 reversed the effects of inhibiting miR-20a expression. • miR-20a has potential application in glioma therapy. [ABSTRACT FROM AUTHOR]

Abstract We successfully excite the multi-mode rain-wind induced vibrations (RWIVs) of a flexible stay cable in a wind tunnel by guiding water rivulets along the cable surface. The first, second and third mode RWIVs are excited respectively by increasing the incoming wind speed. The movement of upper rivulet during the first, second and third mode RWIVs are recorded with a high-speed camera. By employing a computer vision based recognition technique, the upper-rivulet dynamics of different modes of RWIVs are recognized and analyzed. The wake flow structures around the dry cable and the cable suffering from RWIVs are measured by using a particle image velocimetry (PIV) system. Experiment results show that the oscillation frequency of the upper rivulet is synchronized with the cable vibration frequency for the first, second and third mode RWIVs. Based on experiment results, bubble burst is proposed as a possible mechanism for the excitation of RWIVs. [ABSTRACT FROM AUTHOR]

Nitrite-oxidizing bacteria (NOB) are key players in the second step of nitrification, which is an important process in the soil nitrogen (N) cycle. However, the ecology of nitrite oxidizers and their response to disturbances such as long-term fertilization practices are scarcely known in agricultural ecosystems. We used samples from a Red soil subject to a long-term chemical and organic fertilization experiment, including control without fertilizer (CK), swine manure (M), chemical fertilization (NPK), and chemical/manure combined fertilization (MNPK) treatment, to explore how agricultural practices impact the community structure, abundance, and potential activity of nitrite oxidizers (PNO). The abundance of Nitrobacter was significantly increased in the M and MNPK plots, whereas the abundance of Nitrospira was significantly reduced in the M and NPK treatment plots and less inhibited in the MNPK treatment. The PNO showed a similar trend to that for Nitrobacter abundance. The diversity of Nitrobacter increased in the M-treated plots, while that of Nitrospira increased in the M and MNPK plots and decreased in the NPK plots. Non-metric multidimensional scaling (NMDS) revealed that the Nitrobacter - and Nitrospira -like NOB community was shift in these four fertilization treatments. Redundancy analysis showed that pH+SOC (soil organic carbon) and pH+TN (total nitrogen) significantly explained the variation in the composition of Nitrobacter and Nitrospira , respectively. In addition, the Nitrospira/Nitrobacter abundance ratio and community structure of Nitrobacter - and Nitrospira -like NOB are responsible for the changes of soil PNO. Collectively, these data suggest that the nitrite-oxidation process in the red soil is possibly controlled by both Nitrospira and Nitrobacter -like NOB, which were shaped by pH+TN and pH+SOC, respectively. [ABSTRACT FROM AUTHOR]

How nitrite-oxidizing bacteria (NOB) respond to long-term fertilization and variations in soil aggregate levels remains unclear. In this study, the potential nitrite oxidation activity (PNO), abundance, diversity, and community compositions of Nitrobacter - and Nitrospira -like NOB were examined in three aggregate fractions (2000–250, macroaggregate; 250–53, microaggregate; <53 μm, silt + clay) of a Mollisol under four fertilization regimes. NOB abundances were higher in macro- and micro-aggregates, and best explained by aggregate size variation. The PNO, Shannon diversity index and community composition of NOB were more affected by the fertilization regimes. We found PNO significantly correlated with the structure of Nitrospira -like NOB, followed by the abundances and Shannon diversity indexes of NOB. Soil aggregate phosphorus level, total potassium and NH 4 + were associated with the NOB community structure. Our results suggested that PNO directly link to the variations for the abundance, diversity and community structure of NOB, which are regulated by the nutrient level in the microhabitat. [ABSTRACT FROM AUTHOR]

Violent vibrations have been reported in the vertical hangers of long-span suspension bridges, especially for those located in the vicinity of the towers. In the present study, an experimental investigation is performed to characterize the wake-flow-induced vibrations of vertical hangers behind the tower of a suspension bridge. The tower column and vertical cable models are determined by using a long-span suspension bridge with a geometrical scale ratio of 1:10. Regular vortex shedding from the tower column model is detected in the near wake with a Strouhal number ( St ) of 0.20, and the turbulence intensity of the wake flow behind the tower column model is found to be quite high. Arranged at different stations behind the tower column model, the vertical cables experience violent vibrations. The vibration frequencies of the vertical cables are synchronized with the vortex shedding from the upstream tower model within a certain velocity range, during which severe cable vibrations take place. When the incoming wind speed becomes high, the cable vibrations exhibit multimode characteristics. It is also found that the vertical cables arranged at the rear are subject to the combined interferences of the tower column model and the front cables. As a result, the vibration responses of the rear cables are more violent than those of the front cables. [ABSTRACT FROM AUTHOR]

Organo–mineral interactions have been regarded as the primary mechanism for the stabilization of soil organic carbon (SOC) over decadal to millennial timescales, and the capacity for soil carbon (C) storage has commonly been assessed based on soil mineralogical attributes, particularly mineral surface availability. However, it remains contentious whether soil C sequestration is exclusively governed by mineral vacancies, making it challenging to accurately predict SOC dynamics. Here, through a 400‐day incubation experiment using 13C‐labeled organic materials in two contrasting soils (i.e., Mollisol and Ultisol), we show that despite the unsaturation of mineral surfaces in both soils, the newly incorporated C predominantly adheres to "dirty" mineral surfaces coated with native organic matter (OM), demonstrating the crucial role of organo–organic interactions in exogenous C sequestration. Such interactions lead to multilayered C accumulation that is not constrained by mineral vacancies, a process distinct from direct organo–mineral contacts. The coverage of native OM by new C, representing the degree of organo–organic interactions, is noticeably larger in Ultisol (~14.2%) than in Mollisol (~5.8%), amounting to the net retention of exogenous C in Ultisol by 0.2–1.3 g kg−1 and in Mollisol by 0.1–1.0 g kg−1. Additionally, organo–organic interactions are primarily mediated by polysaccharide‐rich microbial necromass. Further evidence indicates that iron oxides can selectively preserve polysaccharide compounds, thereby promoting the organo–organic interactions. Overall, our findings provide direct empirical evidence for an overlooked but critically important pathway of C accumulation, challenging the prevailing "C saturation" concept that emphasizes the overriding role of mineral vacancies. It is estimated that, through organo–organic interactions, global Mollisols and Ultisols might sequester ~0.1–1.0 and ~0.3–1.7 Pg C per year, respectively, corresponding to the neutralization of ca. 0.5%–3.0% of soil C emissions or 5%–30% of fossil fuel combustion globally. [ABSTRACT FROM AUTHOR]

Online learning with the characteristics of flexibility and autonomy has become a widespread and popular mode of higher education in which students need to engage in self-regulated learning (SRL) to achieve success. The purpose of this study is to utilize clickstream data to reveal the time management of SRL. This study adopts learning analytics to investigate the differences in time management (time investment and time use patterns) in a large-scale authentic online learning environment based on 8019 students' clickstream data of over one term recorded by the starC system log. This study quantitatively reveals the SRL process in a higher education online learning environment, which presents the detailed differences in time management among students with different academic performance categories. These research results will have inspirations in the design of SRL interventions for optimizing students' learning processes and overall achievement. [ABSTRACT FROM AUTHOR]

Ureolytic microbes are important contributors to N cycling in soil. The distribution of the ureolytic microbial community in different particle-size fractions (2000-250, 250-53, <53 μm) was determined by high-throughput sequencing and q-PCR analyses in 35-year-old fertilization experiment on Black soil. Fertilizer treatments included an unfertilized control, chemical NPK fertilizer, horse manure and NPK fertilizer plus horse manure. Each fertilizer treatment harbored a structurally distinct ureolytic microbial community. The dominant ureolytic microbes were putatively associated with Rhizobiales , Burkholderiales , Rhodocyclales , Pasteurellales , Pseudomonadales , Oceanospirillales , Myxococcales , Micrococcales and Corynebacteriale species. The OTUs associated with the same fertilizer treatment or particle-size fraction were scattered across the phylogenetic tree, and only sequences related to Rhizobiales showed a similar increase in response to manure application. The abundances of ureC genes ranged from 1.5 ± 0.38 × 10 7 to 9.1 ± 0.91 × 10 7 g −1 dry soil and accounted for 0.4% to 2.9% of the total bacteria (represented by the copy numbers of the 16SrRNA genes). Significantly lower ureC gene abundance was observed in manure-amended soil, whereas the macro- and microaggregates had higher ureC gene abundances than the silt + clay fraction. The abundance of ureolytic microorganisms was significantly correlated with soil NH 4 , total nitrogen (TN) and carbon (TC) concentrations. This indicates that variation in ureolytic microbial communities was associated with soil nutrient levels. Urease activities in the particle-size fractions were as follows: microaggregate > macroaggregate > silt + clay. Additionally, urease activities were correlated with the TN, TC and soil organic carbon (SOC) concentrations, but not with the abundances of the ureC genes. In summary, our study first revealed the heterogeneity in the ureolytic microbial communities and activities across different particle-size fractions under long-term fertilization. Microaggregates seems to be a "hotspot" for nutrients, ureolytic microorganisms and urease activity. [ABSTRACT FROM AUTHOR]

Traumatic brain injury (TBI) is a major cause of chronic disability. Worldwide, it is the leading cause of disability in the under 40s. Behavioral problems, mood, cognition, particularly memory, attention, and executive function are commonly impaired by TBI. Spending to assist, TBI survivors with disabilities are estimated to be costly per year. Such impaired functional outcomes following TBI can be improved via various rehabilitative approaches. The objective of the present paper is to review the current rehabilitation treatment of traumatic brain injury in adults. [ABSTRACT FROM AUTHOR]

[Display omitted] • A series of novel N - (benzene sulfonyl) acetamide derivatives were designed and synthesized. • 9a and 9b showed significant suppressive activity for COX-2, 5-LOX, and TRPV1. • 9a displayed better bioavailability. • 9a showed good anti-inflammatory analgesic activity in vivo. In this study, a series of structurally novel N -(benzene sulfonyl) acetamide derivatives were designed, synthesized, and biologically evaluated as COX-2/5-LOX/TRPV1 multitarget inhibitors for anti-inflammatory and analgesic therapy. Among them, 9a and 9b displayed favorable COX-2 (9a IC 50 = 0.011 μM, 9b IC 50 = 0.023 μM), 5-LOX (9a IC 50 = 0.046 μM, 9b IC 50 = 0.31 μM) and TRPV1 (9a IC 50 = 0.008 μM, 9b IC 50 = 0.14 μM) inhibitory activities. The pharmacokinetic (PK) study of 9a in SD rats at the dosage of 10 mg/kg demonstrated a high oral exposure, an acceptable clearance and a favorable bioavailability (Cmax = 5807.18 ± 2657.83 ng/mL, CL = 3.24 ± 1.47 mL/min/kg, F = 96.8 %). Further in vivo efficacy studies illustrated that 9a was capable of ameliorating formalin-induced pain and inhibiting capsaicin-induced ear edema. [ABSTRACT FROM AUTHOR]

Online peer feedback plays a critical role in collaborative learning. This process improves learning and helps both giver and receiver develop and refine their metacognitive knowledge. A deeper examination of the feedback types, specificity, and affective nature is needed to understand its impact on collaborative knowledge improvement. A mixed-method study was conducted to examine how online peer feedback supported collaborative knowledge improvement in a computer-supported collaborative learning (CSCL) environment. How the different types of formative peer feedback, the specificity and affective nature of the peer comments supported pre-service teachers' in improving their TEL design were examined. The results showed that the peer feedback supported pre-service teachers in improving the quality of TEL design measured by the TPACK framework. It was found that feedback that raised concerns about the work and suggestive feedback facilitated the further improvement of the work. Elaborated feedback rather than verification feedback with short responses also affected the responses to the feedback. The implications on how online peer feedback support collaborative knowledge improvement are discussed. • Online peer feedback can support pre-service teachers in improving the quality of TEL design measured by the TPACK framework. • Elaborated feedback promotes post-feedback behaviour and supports pre-service teachers' improvement. • Feedback type questions and concerns and suggestions could feedforward, leading to collaborative knowledge improvement. • The affective state of the feedback comments does not influence how the recipient responds to the feedback. [ABSTRACT FROM AUTHOR]

AKR1B10 is a member of the human aldo–keto reductase superfamily which is highly expressed in several types of cancers, and has been regarded as a promising cancer therapeutic target. In this paper, a series of polyhydroxy steroids were designed and synthesized to selectively inhibit AKR1B10 activity. The most selective compound, novel compound 6, has an IC 50 of 0.83 ± 0.07 μM and a selectivity of more than 120-fold for AKR1B10/AKR1B1. Structure–activity relation analyses indicate that hydroxyl at C-19 can significantly improve the selective inhibition of AKR1B10. The binding mode of AKR1B10 and its inhibitors were studied. [ABSTRACT FROM AUTHOR]

Spiking neural P systems (SN P systems, for short) are a class of distributed parallel computing devices inspired from the way neurons communicate by means of spikes. In this work, we consider SN P systems with the following restriction: at each step the active neuron with the maximum (or minimum) number of spikes among the neurons that can spike will fire [if there is a tie for the maximum (or minimum) number of spikes stored in the active neurons, only one of the neurons containing the maximum (or minimum) is chosen non-deterministically]. We investigate the computational power of such sequential SN P systems that are used as language generators. We prove that recursively enumerable languages can be characterized as projections of inverse-morphic images of languages generated by such sequential SN P systems. The relationships of the languages generated by these sequential SN P systems with finite and regular languages are also investigated. [ABSTRACT FROM AUTHOR]

Spiking neural P systems (SN P systems, for short) are a class of distributed parallel computing devices inspired from the way neurons process information and communicate by means of spikes, where neurons are different in the sense that they can have different sets of spiking rules. In this work, we consider a variant of SN P systems with two restrictions: (1) all neurons contain only spikes (neurons are homogeneous in this case, since they can be considered as containers of spikes), while the spiking rules are moved on the synapses; (2) all synapses are homogeneous in the sense that each synapse has the same set of rules. These restrictions correspond to the fact that the SN P system consists of only one kind of neurons and one kind of synapses. The computational power of SN P systems with homogeneous neurons and synapses is investigated. Specifically, it is proved that such systems are Turing universal as both number generating and number accepting devices. [ABSTRACT FROM AUTHOR]

Bacterial attachment is a physicochemical interfacial process probably affected by the presence of humic acid (HA) in natural environments. However, the effect of HA coating on bacterial adhesion to soil minerals remains unknown, despite many studies focusing on cell attachment to pure or iron oxide-coated quartz in the presence of HA. The influence of HA on Bacillus subtilis adhesion to kaolinite, montmorillonite, and goethite under neutral pH and 1 mM ionic strength was examined using batch experiments coupled with Fourier-transform infrared spectroscopy (FTIR), isothermal titration calorimetry, and Derjaguin, Landau, Verwey, and Overbeek (DLVO) theory. Results showed a reduction in cell adhesion on goethite and montmorillonite with increasing HA content from 0% to 2%, indicating an inhibitory effect of HA coating on the interaction. However, a promotive effect of HA was observed for kaolinite, which disagreed with previous findings based on cell–quartz systems. In addition, the presence of HA reduced the exothermic adhesion enthalpy for kaolinite and goethite, but increased that for montmorillonite. For goethite, the HA coating depressed its positive charge and increased its aggregation, thereby leading to a weaker electrostatic attraction and lesser available surface area, which probably contributed to the observed decreasing adhesion. For montmorillonite, the reduced attachment was likely caused by the increase in electrostatic repulsion that overcompensated for the appeared chemical interactions as suggested by FTIR analysis. The enhanced cell adhesion on kaolinite, which was unexpected from DLVO theory based on its surface charge change, is likely ascribed to the HA-induced decrease in its aggregation. Additionally, the effect of HA vanishes at HA contents higher than 2%, likely due to a saturation effect. Overall, the influence of HA on bacterial attachment is likely a combined result of multiple factors, including not only electrostatic forces and chemical interactions, but also mineral aggregation. [ABSTRACT FROM AUTHOR]

Bacterial adhesion to minerals in soils and sediments is of fundamental importance in mineral weathering and formation, soil aggregate stability, organic matter degradation and the fate of pollutants. Bacterial surface properties are considered to govern adhesion, and these properties likely change as a function of bacterial growth phase. However, the effect of growth stage on bacterial adhesion to clay minerals remains unclear. This work examined the influence of growth phase on the adhesion of Pseudomonas putida to kaolinite-coated coverslips. Fluorescence microscopy, together with a bacterial viability stain, was used to directly quantify surface cell density and viability of adhered P. putida . In situ attenuated total reflectance Fourier transform infrared spectroscopy was applied to yield molecular information about the characteristics of the bacteria, and the adsorption and desorption kinetics. Stationary-phase cells exhibited a higher adsorption density on kaolinite surfaces than mid-exponential-phase cells under static deposition conditions. Compared with the mid-exponential-phase cells, the stationary-phase cells displayed higher saturation coverage, and we fitted the results using a pseudo-first-order kinetics equation. The greater extent of adhesion of the stationary-phase cells was probably due to their smaller cell size and less negative surface charges compared with the cells from other growth stages, which resulted in deeper secondary energy minima and lower energy barriers for adhesion. The results from this study suggest that growth phase may strongly influence cell mobility and biofilm formation in aqueous geochemical environments. [ABSTRACT FROM AUTHOR]

Myasthenia gravis (MG) is an autoimmune disease caused by circulating antibodies that block acetylcholine receptor (AchR) at the neuromuscular junction. There is the cognitive and memory impairment in patients with MG. However, the molecular mechanisms underlying the alteration of central nervous system in MG remain unknown. In the present study, we found that the level of malondialdehyde (MDA) was increased in the brain of experimental autoimmune myasthenia gravis (EAMG). Furthermore, the expression of thioredoxin-1 (Trx-1) and the activity of cAMP response element-binding protein (CREB) were significantly decreased in frontal lobe and hippocampus of mice with EAMG. We also found that the expression of pro-apoptotic C/EBP homologous protein (CHOP) was increased in the frontal lobe and hippocampus of mice. However, the expressions of glucose regulated protein 78 (GRP78/Bip) was not changed in same areas. Inversely, the expressions of pro-caspase-12, pro-caspase-3 and pro-caspase-9 were decreased. These data indicate that Trx-1 mediated endoplasmic reticulum and mitochondria pathways are involved in brain damage in MG. Trx-1 may be a pivotal target for brain protective treatment in MG. [ABSTRACT FROM AUTHOR]

Substantial interactions of microbes with soil particles present fundamental influences on microbial activities relevant to a series of biogeochemical processes. However, how soil surface-active particles modulate microbial metabolism has received scant attention. The extent to which composition of soil colloids alter the metabolism is not well addressed. This work examined the impacts of soil colloids and minerals on the metabolic activity ofPseudomonas putidausing microcalorimetry and carbon utilization. The results showed that montmorillonite remarkably improved metabolic activity ofP. putida, whereas kaolinite, goethite and soil colloids significantly inhibited the activity. Humus may weaken the inhibition of soil colloids on bacterial metabolism via interfacial interaction rather than nutrient supplements. Soils bearing higher amount of kaolinite and iron oxide may have greater depression on bacterial activity. The thermodynamic method provides different and complementary information to that from other techniques in characterizing microbial activities. The quantity and affinity for the adhesion of bacteria onto soil components together with the detoxification of metabolites were assigned to the modifications of bacterial activities. [ABSTRACT FROM PUBLISHER]

In the present study, a coupled wake oscillator dynamic equation was established to predict the vortex-induced vibration (VIV) response of a circular cylinder immersed in a fluid. A classical structural dynamic equation was applied to describe the one-degree-of-freedom vibration of a circular cylinder. The revised van der Pol equation was used to model the wake flow dynamics and the fluctuating aerodynamic force derived from periodic alternating vortex shedding. The coupled structural dynamic equation and revised van der Pol equation were utilized to describe the features of VIV, such as the frequency component of aerodynamic forces, vibration amplitude, and lock-in domains. The results show that the proposed model can more precisely predict the VIV response and frequency features. An experiment was performed to study the passive jet flow control for VIV of a circular cylinder. The surface pressure distribution was measured to obtain the sectional aerodynamic forces acting on the model containing passive jet rings with different distances. The influencing range of the aerodynamic force caused by the passive jet rings was obtained and incorporated into the coupled model. The revised coupled model was found to predict well the VIV response of a circular cylinder equipped with adjacent passive jet rings having different distances. • The improved model is successfully to model the completely dominant frequency component for the lift force acting on circular cylinder. • The coupled model can predict the oscillation amplitude and lock-in of vortex induced vibration (VIV) of circular cylinder. • Revised coupled model commendably predict the control effectiveness for VIV of circular cylinder equipped with passive jet ring. [ABSTRACT FROM AUTHOR]

The study was conducted with the objective to assess soil enzymatic, microbial, and chemical properties by customary methods and results obtained by conventional methods, corroborated with microcalorimetry. The experiment was laid out in a randomized complete block design with ten treatments in triplicates. The RS and GM were used at three rates (0, 5, and 25 mg g soil, respectively). The soils were maintained at two water levels 25 % (W1) and 200 % (W2) of soil water-holding capacity. All soil enzymatic, microbial, and chemical properties were measured by standard methods. The incorporation of GM and RS, especially at high rates and water levels, 25 % (W1) and 200 % (W2) significantly ( p < 0.05) affected the soil enzymatic, microbial, and chemical properties compared to controls. The microcalorimetric parameters P and k were positively correlated, whereas t negatively linked with the results of enzymatic, microbial, and chemical properties at p < 0.01. Conversely, Q elucidated non-significant correlation ( p < 0.05) to urease (0.248), neutral phosphatase (0.281), dehydrogenase (0.291), MBC (0.283), MBP (0.277), DOC (0.269), DON (0.190), SOM (0.284), and pH (0.047). Our results suggested that calorimetric parameters P, t, and k are highly sensitive and could be used as indices of soil enzymatic, microbial, and chemical properties, while Q is an indigent indicator. [ABSTRACT FROM AUTHOR]

Abstract: The functions of extracellular polymeric substances (EPS) during the adhesion of Bacillus subtilis to kaolinite, montmorillonite, and goethite were examined by a direct comparison of the adhesion behaviors of native and EPS-free cells via cation exchange resin (CER) treatment using batch experiments, attenuated total reflectance Fourier-transform infrared (ATR-FTIR) spectroscopy, and potentiometric titration. The EPS removal had no apparent influence on bacterial adhesion when the wet bacteria/mineral mass ratio was low (<0.4 for the clay mineral systems and <1.8 for the goethite system). With higher mass ratios, the absence of EPS reduced adhesion to clay minerals but enhanced adhesion to goethite. The ATR-FTIR spectra suggested that protein conformational changes were involved in the adhesion of bacteria to clay minerals, whereas additional chemical interactions such as P OFe bonds were important for adhesion to goethite. In addition to electrostatic forces (repulsion for clays and attraction for goethite), absence of chemical interactions may also cause the relatively much weaker bacterial adhesion to clay minerals than to goethite. The absence of EPS did not change the interaction mode of the adhesion to clay minerals but enhanced the chemical interactions via carboxyl groups for bacteria–goethite adhesion. The potentiometric titration results coupled with the ATR-FTIR spectra showed a significant increase in site concentrations of the CER-treated bacteria as compared to the native cells. Changes in surface site concentrations and chemical interactions that were accompanied by the EPS removal may reasonably explain the influences of EPS on bacterial adhesion to different minerals. [Copyright &y& Elsevier]

Monkey metallothionein α domain tandem repeats (4mMTα), which exhibit high cadmium affinity, have been displayed for the first time on the surface of a bacterium using ice nucleation protein N-domain ( inaXN) protein from the Xanthomonas campestris pv (ACCC-10049) as an anchoring motif. The shuttle vector pIME, which codes for INAXN-4mMTα-EGFP fusion, was constructed and used to target 4mMTα and EGFP on the surface of Pseudomonas putida X4 (CCTCC-209319). The surface location of the INAXN-4mMTα-EGFP fusion was further verified by western blot analysis and immunofluorescence microscopy. The growth of X4 showed resistance to cadmium presence. The presence of surface-exposed 4mMTα on the engineered strains was four times higher than that of the wild-type X4. The Cd accumulation by X4/pIME was not only four times greater than that of the original host bacterial cells but was also remarkably unaffected by the presence of Cu and Zn. Moreover, the surface-engineered strains could effectively bind Cd under a wide range of pH levels, from 4 to 7. P. putida X4/pIME with surface-expressed 4mMTα-EGFP had twice the cadmium binding capacity as well as 1.4 times the fluorescence as the cytoplasmic 4mMTa-EGFP. These results suggest that P. putida X4 expressing 4mMTα-EGFP with the INAXN anchor motif on the surface would be a useful tool for the remediation and biodetection of environmental cadmium contaminants. [ABSTRACT FROM AUTHOR]

A growing body of evidence indicates that second-generation energy crops can play an important role in the development of renewable energy and the mitigation of climate change. However, dedicated energy crops have yet to be domesticated in order to fully realize their productive potential under unfavorable soil and climatic conditions. To explore the possibility of domesticating Miscanthus crops in northern China where marginal and degraded land is abundant, we conducted common garden experiments at multiple locations to evaluate variation and adaptation of three Miscanthus species that are likely to serve as the wild progenitors of the energy crops. A total of 93 populations of Miscanthus sinensis, Miscanthus sacchariflorus, and Miscanthus lutarioriparius were collected across their natural distributional ranges in China and grown in three locations that represent temperate grassland with cold winter, the semiarid Loess Plateau, and relatively warm and wet central China. Evaluated with growth traits such as plant height, tiller number, tiller diameter, and flowering time, the Miscanthus species showed high levels of genetic variation within and between species. There were significant site × population interactions for almost all traits of M. sacchariflorus and M. sinensis, but not M. lutarioriparius. The northern populations of M. sacchariflorus had the highest establishment rates at the most northern site owing to their strong cold tolerance. An endemic species in central China, M. lutarioriparius, produced not only the highest biomass of the three species but also higher biomass at the Loess Plateau than the southern site near its native habitats. These results demonstrated that the wild species harbored a high level of genetic variation underlying traits important for crop establishment and production at sites that are colder and drier than their native habitats. The natural variation and adaptive plasticity found in the Miscanthus species indicated that they could provide valuable resources for the development of second-generation energy crops. [ABSTRACT FROM AUTHOR]

The article employs the uses and gratifications theory to examine the relationship between the level of satisfaction on the computer-mediated social support (CMSS) received and the possible continued seeking of CMSS among Chinese migrants in Singapore who are Internet users. Data analysis show that about 90 percent of the migrants sought CMSS, particularly for informational help, sharing of digital products, tangible support such as giving a free lift or lending a book, and companionship and emotional support. Migrants indicated their satisfaction in all the four types of CMSS they received. Other factors influencing CMSS-seeking behavior include longer stay in the host country and face-to-face social support.

A key stimulus of learning efficacy for students in the classroom is active participation and engagement in the learning process. This study examines the nature of teacher-student and student-student discourse when leveraged by an interactive technology-Group Scribbles (GS) in a Primary 5 Science classroom in Singapore which supports rapid collaborative knowledge building (RCKB). We envisaged nine design principles for RCKB in the design of lessons and postulated a logic model that links and explains the effects of our design principles to the ultimate goal of learning efficacy. We presented a case study of a GS lesson which shows that GS affordances leveraged by good lesson and activity design could enable the students to have more epistemic agency. Students had opportunities to participate spontaneously in class discussions by fully expressing their ideas without inhibition. The technology effect is used to support instant formative feedback and interactions among students effectively. [ABSTRACT FROM AUTHOR]

As a widespread pollutant in the environment, cadmium (Cd) would be accumulated in leaves and cause phytotoxic effect on plants. Salicylic acid (SA), a natural signal molecule, plays an important role in eliciting specific responses to biotic and abiotic stresses. In our case, the effect of SA on Cd-induced photochemical damage and cell death in Arabidopsiswas studied. The results illustrated that Cd could cause a series of physiological events such as chloroplast structure change (e.g.irregular mesophyll cell as well as ultrastructure change), reactive oxygen species (ROS) production and cell death. Furthermore, chlorophyll fluorescence parameters (Fv/Fm, qN and ETR) showed a rapid decrease in wild-type (WT) Arabidopsisafter treatment with 50 μM CdCl2, identical with the change in chlorophyll delayed fluorescence (DF) intensity. The changes of these parameters showed the damage of Cd toxicity to photosynthetic apparatus. We found that cell death might be autophagic cell death, which might be caused by Cd toxicity induced oxidative stress just like photosynthetic damage. The NahG plants with lower SA accumulation level showed more sensitivity to Cd toxicity, although they exhibited a decrease both in chlorophyll fluorescence parameters and DF intensity. Exogenously SA prevented the Cd-induced photochemical efficiency decrease and mitigated Cd toxicity. Additionally, SA pretreatment could alleviate Cd-induced ROS overproduction. In conclusion, our results suggested that SA could prevent Cd-induced photosynthetic damage and cell death, which might be due to the inhibition of ROS overproduction. [ABSTRACT FROM AUTHOR]