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Polygonatum cyrtonema Hua is a traditional Chinese herb propagated using rhizomes, and excessive demand for seedlings and quality deterioration caused by rhizome propagation has highlighted that seed propagation may be an ideal solution to address these issues. However, the molecular mechanisms involved in P. cyrtonema Hua seed germination and emergence stages are not well understood. Therefore, in the present study, we performed transcriptomics combined with hormone dynamics during different seed germination stages, and 54,178 unigenes with an average length of 1390.38 bp (N50 = 1847 bp) were generated. Significant transcriptomic changes were related to plant hormone signal transduction and the starch and carbohydrate pathways. Genes related to ABA(abscisic acid), IAA(Indole acetic acid), and JA(Jasmonic acid) signaling, were downregulated, whereas genes related to ethylene, BR(brassinolide), CTK(Cytokinin), and SA(salicylic acid) biosynthesis and signaling were activated during the germination process. Interestingly, GA biosynthesis- and signaling-related genes were induced during the germination stage but decreased in the emergence stage. In addition, seed germination significantly upregulated the expression of genes associated with starch and sucrose metabolism. Notably, raffinose biosynthesis-related genes were induced, especially during the emergence stage. In total, 1171 transcription factor (TF) genes were found to be differentially expressed. Our results provide new insights into the mechanisms underlying P. cyrtonema Hua seed germination and emergence processes and further research for molecular breeding.

To improving the understand of the accumulation pattern of soluble sugars in Magnolia wufengensis during natural cold acclimation, the dynamics of freezing tolerance, the content of various soluble sugars in the shoots of M. wufengensis seedlings treated with salicylic acid, and the correlation between them were analyzed from September 2017 to March 2018. Salicylic acid advanced the natural cold acclimation and ultimately enhanced mid-winter hardiness by promoting the accumulation of total soluble sugars. Improved freezing tolerance highly correlated with enhanced glucose, fructose, and raffinose accumulation. The enhanced accumulation of these sugars by elevated amylase, sucrose synthase, and sucrose-P-synthase activities may contribute to advanced natural cold acclimation.

Background Magonlia denudata is an important perennial tree species of the Magnoliaceae family, known for its ornamental value, resistance to smoke pollution and wind, role in air purification, and robust cold tolerance. In this study, a high-throughput transcriptome analysis of leaf buds was performed, and gene expression following artificial acclimation 22 °C, 4 °C and 0 °C, was compared by RNA sequencing. Results Over 426 million clean reads were produced from three libraries (22 °C, 4 °C and 0 °C). A total of 74,503 non-redundant unigenes were generated, with an average length of 1173.7 bp (N50 = 1548). Based on transcriptional results, 357 and 235 unigenes were identified as being upregulated and downregulated under cold stress conditions, respectively. Differentially expressed genes were annotated using Gene Ontology and the Kyoto Encyclopedia of Genes and Genomes pathway analyses. The transcriptomic analysis focused on carbon metabolism and plant hormone signal transduction associated with cold acclimation. Transcription factors such as those in the basic helix-loop-helix and AP2/ERF families were found to play an important role in M. denudata cold acclimation. Conclusion M. denudata exhibits responses to non-freezing cold temperature (4 °C) to increase its cold tolerance. Cold resistance was further strengthened with cold acclimation under freezing conditions (0 °C). Cold tolerance genes, and cold signaling transcriptional pathways, and potential functional key components for the regulation of the cold response were identified in M. denudata. These results provide a basis for further studies, and the verification of key genes involved in cold acclimation responses in M. denudata lays a foundation for developing breeding programs for Magnoliaceae species.

We present PerformanceVis, a visual analytics tool for analyzing student admission and course performance data and investigating homework and exam question design. Targeting a university-wide introductory chemistry course with nearly 1000 student enrollment, we consider the requirements and needs of students, instructors, and administrators in the design of PerformanceVis. We study the correlation between question items from assignments and exams, employ machine learning techniques for student grade prediction, and develop an interface for interactive exploration of student course performance data. PerformanceVis includes four main views (overall exam grade pathway, detailed exam grade pathway, detailed exam item analysis, and overall exam & homework analysis) which are dynamically linked together for user interaction and exploration. We demonstrate the effectiveness of PerformanceVis through case studies along with an ad-hoc expert evaluation. Finally, we conclude this work by pointing out future work in this direction of learning analytics research. Keywords: Student performance, Item analysis, Grade prediction, Learning analytics, Knowledge discovery

Electrocatalysts play a vital role to overcome the slow kinetics of the oxygen evolution reaction (OER). Herein, we developed iron-doped (Fe-doped) NiCoO 2 nanoplates with NaCl-type structure as an efficient electrocatalyst to speed up OER. NiCoO 2 nanoplates doping with different concentration of Fe were optimized. Specifically, the catalytic properties of 10 mol% Fe-doped NiCoO 2 (denoted as FNC0.1) showed outstanding OER catalytic activity, with an overpotential of 302 mV and a low Tafel slope of 42 mV dec −1 at 10 mA cm −2 in 0.1 M KOH. More importantly, the activity of FNC0.1 was only about 3% loss after 10 h of stability measurements at 1.53 V vs. RHE. The dramatically enhanced OER performance of the FNC0.1 might derive from the synergistic interplay of Co, Ni and Fe, a certain level of amorphization and easily hydroxylation after doping Fe. This work demonstrated that doping Fe would be beneficial to improve the OER activities and the stabilities of the catalysts.

Liquid-phase exfoliation is an effective method to fabricate thin nanosheet materials with layered structure. In this paper, we successfully synthesized NH 4 Co 0.4 Ni 0.6 PO 4 ·H 2 O nanosheets with the thickness of about tens of nanometers through liquid-phase exfoliation under ultrasonication. Specifically, the formamide solution was chosen as the exfoliation solvent due to it is capable of entering the interlayer of bulk materials and rapidly swelling between layers. Electrochemistry tests revealed that the optimized exfoliation time was 4 days. The asymmetric battery type energy storage device AC//NH 4 Co 0.4 Ni 0.6 PO 4 ·H 2 O nanosheets showed an energy density of 10.8 Wh kg −1 at the power density of 703.1 W kg −1 . More importantly, the long-term cycle stability measurements demonstrated that NH 4 Co 0.4 Ni 0.6 PO 4 ·H 2 O nanosheets after exfoliation had an ultra-long cycling life that still retained 102.3% of specific capacitance even 10000 continuous charge/discharge cycles.

Magnolia wufengensis L.Y. Ma et L. R. Wang, a rare species which has been introduced and cultivated from southern China to northern China, frequently suffers from freezing injuries. To figure out the influence of ethephon (ETH) application on the cold tolerance during the natural overwintering of M. wufengensis, one-year shoots subjected to ethephon application at four concentrations (0, 700, 1000, and 1500 mg&middot, L&minus, 1) were collected to measure the physiological and biochemical changes from September 2017 to 1 April 2018. The fall ETH application increased the freezing tolerance of M. wufengensis, and the optimum concentration for M. wufengensis was 1000 mg&middot, 1 (T2), which not only improved the shoot freezing tolerance by 1.4 times, but also led to a 25.0% faster cold acclimation rate and 13.7% slower de-acclimation rate. Moreover, 1000 mg&middot, 1 ETH delayed bud-burst in the spring by 10. 7 d, which was helpful for effectively avoiding cold spells in the spring, and improved the rates of bud survival by 47.1%. The improved freezing tolerance under exogenous ETH application was associated with an increased dehydration and accumulation of proline content. It seems that exogenous ETH application may be used on M. wufengensis grown in northern China to protect against freezing tolerance during the overwintering period.

To investigate the influence of exogenous paclobutrazol (PBZ) application on the natural cold acclimation of Ligustrum lucidum, 1-year-old L. lucidum seedlings were conducted with PBZ at four concentrations (0, 100, 300, and 500 mg L−1) from September to December 2016, and leaves were collected to measure physiological and biochemical parameters. Results showed that 500 mg L−1 was the optimum concentration, which led to stronger freezing tolerance during natural cold acclimation. The enhanced freezing tolerance induced by exogenous PBZ application was attributed to the accumulation of chlorophyll, proline, soluble protein, and soluble sugar, and the regulation of gibberellic acid and abscisic acid. PBZ treatments initiated a cascade of steps for advancing the cold acclimation of L. lucidum. It appears that exogenous PBZ application may be applied to L. lucidum grown in northern China, where the growing periods are short and there are early fall frost events and low mid-winter temperatures.

The study aims to investigate the correlation between the parameters of contrast-enhanced ultrasonography in evaluating cervical cancer metastasis and expression of E-cadherin. All 120 patients with cervical cancer underwent contrast-enhanced ultrasonography. According to the results of postoperative pathological examination, patients were divided into distant metastasis group (group A), lymph node metastasis without distant metastasis group (group B) and no metastasis group (group C). Expression of E-cadherin in cervical cancer tissues was detected by enzyme-linked immunosorbent assay (ELISA). Correlations between the parameters of contrast-enhanced ultrasonography in evaluating cervical cancer metastasis and expression of E-cadherin were analyzed by Pearsons correlation analysis. Comparison of parameters of contrast-enhanced ultrasonography showed that, the baseline intensity of group A was 11.9±2.2 dB, which was significantly lower than that of group B and C. Baseline intensity of group B was significantly lower than that of group C (13.0±2.4 vs. 15.3±3.6 dB), significant differences were found among three groups (P

As more and more college classrooms utilize online platforms to facilitate teaching and learning activities, analyzing student online behaviors becomes increasingly important for instructors to effectively monitor and manage student progress and performance. In this paper, we present CCVis, a visual analytics tool for analyzing the course clickstream data and exploring student online learning behaviors. Targeting a large college introductory course with over two thousand student enrollments, our goal is to investigate student behavior patterns and discover the possible relationships between student clickstream behaviors and their course performance. We employ higher-order network and structural identity classification to enable visual analytics of behavior patterns from the massive clickstream data. CCVis includes four coordinated views (the behavior pattern, behavior breakdown, clickstream comparative, and grade distribution views) for user interaction and exploration. We demonstrate the effectiveness of CCVis through case studies along with an ad-hoc expert evaluation. Finally, we discuss the limitation and extension of this work.

Subsurface drip distribution is an important on-site wastewater treatment technique widely used with various soil types and restricted site conditions. This study evaluated the performance of five subsurface wastewater drip products under eight pressures, ranging from 0 to 310 kPa. Results showed that Netafim Bioline pressure-compensating emitters (Netafim Irrigation Inc., Fresno, California) had an application uniformity coefficient of 95% and a coefficient of variance (C v ) of 4.9%. The average uniformity coefficient of Geoflow Wasteflow products (Geoflow USA, Charlotte, North Carolina) was 94.4%, with a C v value of 6.8%. Flowrate and pressure relationships were developed by analyzing low and normal operational pressure ranges, and /?-square values ranged from 1.000 to 0.301. Geoflow pressure-compensating products were non-pressure-compensating emitters under low pressure. Netafim pressure-compensating emitters were partially pressure-compensating under low pressures. In normal operational pressure ranges, both Geoflow and Netafim products were fully pressure-compensating. Netafim pressure-compensating products were characterized as pressure-compensating over the full range of operational pressures.

An on-site wastewater treatment project with two separate drip fields was operated for 6 years and received no maintenance. The two drip fields (with different design configurations) contained pressure-compensating emitters (PC) and non-pressure-compensating emitters (NPC), respectively, and received wastewater with an average 5-day biochemical oxygen demand concentration of 23 mg/L. Flowrates of the PC emitters reduced from rated average of 3.50 to 1.00 L/h, and the average flowrate of the NPC emitters reduced from 2.00 to 1.53 L/h. The statistical uniformities were 48 and 71%, and the uniformity coefficients were 70 and 86% for PC and NPC emitters, respectively. Significant, but incomplete, recovery was achieved with field-flushing and consecutive shock-chlorination treatments of 500 and 1000 mg/L.

In order to evaluate drip zone configurations with respect to distribution uniformity, a field-scale experiment was set up and three drip tubing products were tested in different dosing and operation schemes. Three factors of wastewater drip system design were tested. System operation pressure (138 kPa and 276 kPa); different pressure control schemes (usage of pressure regulator/recirculation valve/continuous flushing/intermittent flushing); and supply line length (7.6 m, 15.2 m and 30.4 m) were evaluated to compare their influence on water application uniformity. It was concluded that, for Geoflow PC and NPC products, among all three factors, system operational pressure has the greatest effect on drip system application uniformity; supply line length has the least influence. For Netafim PC tubing, pressure control scheme has the greatest effect on drip system application uniformity; supply line length has the least influence. The optimal combination of the three factors could save more than 10 minutes of dosing time to meet the required distribution application uniformity. Drip zone dose time under required application uniformity was computed on the layout of different runs per lateral.

The mobile revolution is finally here. The evidence of mobile penetration and adoption is irrefutable. Mobile devices are getting smaller and more powerful. They have the ability to deliver learning objects and provide access to online systems and services. M-learning is a natural extension of e-learning. It has the potential to further expand where, how and when we learn and perform in all the aspects of our life. M-learning will not replace traditional learning. It fulfils the growing demands for lifelong learning opportunities that enable learners to 'learn while you earn on the go'.

The area lateral to the stria medullaris and the fornix at the level of the interventricular foramen, an area known to be occupied by the medial dorsal accessory group and the anterior fornical nucleus of the magnocellular neurosecretory system, was found to be studded with serotonin (5-HT)-like immunoreactive (LI) varicosities. Double immunostaining with antisera against 5-HT and oxytocin (OXY) proved that the 5-HT-LI varicosities were in close proximity to the OXY-LI neurons in the medial dorsal accessory group and the anterior fornical nucleus. These nuclei were distributed more densely with 5-HT-LI varicosities than other cell groups in the magnocellular neurosecretory system.