35 research outputs found
Stock Index Futures Trading Impact on Spot Price Volatility. The CSI 300 studied with a TGARCH model
A TGARCH modeling is argued to be the optimal basis for investigating the impact of index futures trading on spot price variability. We discuss the CSI-300 index (China-Shanghai-Shenzhen-300-Stock Index) as a test case. The results prove that the introduction of CSI-300 index futures (CSI-300-IF) trading significantly reduces the volatility in the corresponding spot market. It is also found that there is a stationary equilibrium relationship between the CSI-300 spot and CSI-300-IF markets. A bidirectional Granger causality is also detected. āFinallyā, it is deduced that spot prices are predicted with greater accuracy over a 3 or 4 lag day time span.<br
Table_3_On a path to becoming more self-regulated: Reflective journalsā impact on Chinese English as a foreign language studentsā self-regulated writing strategy use.docx
A number of studies have confirmed the positive effect of writing reflective journals on L2 learning. However, the relationship between writing reflective journals and the use of self-regulated writing strategies remains unclear. To redress this knowledge gap, we assigned 38 Chinese English as a foreign language (EFL) students three journal-writing tasks in which they reflected on their writing processes and explored (1) the types of self-regulated writing strategies and changes to those strategies that the studentsā reflective journals documented; (2) how students with varied writing-proficiency levels differed in their use of self-regulated writing strategies; and (3) the effects of reflective-journal writing on studentsā self-perceived use of self-regulated writing strategies in particular, and on their L2 writing in general. Among the 19 kinds of strategies identified in 112 reflective-journal entries, only five (i.e., handling feedback, resource management, text processing, emotion regulation, and idea planning) were demonstrated relatively frequently. The use of seven strategies (i.e., self-monitoring and evaluation, idea planning, perspective change, emotional control, effort regulation, peer learning, and resource management) exhibited significant increases over time, especially during the second-half of the focal semester. In addition, our journal data highlighted individual variation in proficiency levels: with high-proficiency students significantly more likely than others to apply idea planning, feedback handling, and resource management and low-proficiency ones significantly more likely than others to engage in goal-setting. The qualitative results suggest that the practice of journaling raised studentsā awareness and may have contributed to an increase in their use of self-regulated writing strategies. In particular, the findings reveal how students internalized and reconstructed the various SRL processes taking place via writing reflective journals. For L2 educators using or considering using reflective journals, these findings contain fresh insights that could help them not only to increase their studentsā SRL levels, but also to provide more individualized SRL guidance.</p
Table_4_On a path to becoming more self-regulated: Reflective journalsā impact on Chinese English as a foreign language studentsā self-regulated writing strategy use.docx
A number of studies have confirmed the positive effect of writing reflective journals on L2 learning. However, the relationship between writing reflective journals and the use of self-regulated writing strategies remains unclear. To redress this knowledge gap, we assigned 38 Chinese English as a foreign language (EFL) students three journal-writing tasks in which they reflected on their writing processes and explored (1) the types of self-regulated writing strategies and changes to those strategies that the studentsā reflective journals documented; (2) how students with varied writing-proficiency levels differed in their use of self-regulated writing strategies; and (3) the effects of reflective-journal writing on studentsā self-perceived use of self-regulated writing strategies in particular, and on their L2 writing in general. Among the 19 kinds of strategies identified in 112 reflective-journal entries, only five (i.e., handling feedback, resource management, text processing, emotion regulation, and idea planning) were demonstrated relatively frequently. The use of seven strategies (i.e., self-monitoring and evaluation, idea planning, perspective change, emotional control, effort regulation, peer learning, and resource management) exhibited significant increases over time, especially during the second-half of the focal semester. In addition, our journal data highlighted individual variation in proficiency levels: with high-proficiency students significantly more likely than others to apply idea planning, feedback handling, and resource management and low-proficiency ones significantly more likely than others to engage in goal-setting. The qualitative results suggest that the practice of journaling raised studentsā awareness and may have contributed to an increase in their use of self-regulated writing strategies. In particular, the findings reveal how students internalized and reconstructed the various SRL processes taking place via writing reflective journals. For L2 educators using or considering using reflective journals, these findings contain fresh insights that could help them not only to increase their studentsā SRL levels, but also to provide more individualized SRL guidance.</p
Table_2_On a path to becoming more self-regulated: Reflective journalsā impact on Chinese English as a foreign language studentsā self-regulated writing strategy use.docx
A number of studies have confirmed the positive effect of writing reflective journals on L2 learning. However, the relationship between writing reflective journals and the use of self-regulated writing strategies remains unclear. To redress this knowledge gap, we assigned 38 Chinese English as a foreign language (EFL) students three journal-writing tasks in which they reflected on their writing processes and explored (1) the types of self-regulated writing strategies and changes to those strategies that the studentsā reflective journals documented; (2) how students with varied writing-proficiency levels differed in their use of self-regulated writing strategies; and (3) the effects of reflective-journal writing on studentsā self-perceived use of self-regulated writing strategies in particular, and on their L2 writing in general. Among the 19 kinds of strategies identified in 112 reflective-journal entries, only five (i.e., handling feedback, resource management, text processing, emotion regulation, and idea planning) were demonstrated relatively frequently. The use of seven strategies (i.e., self-monitoring and evaluation, idea planning, perspective change, emotional control, effort regulation, peer learning, and resource management) exhibited significant increases over time, especially during the second-half of the focal semester. In addition, our journal data highlighted individual variation in proficiency levels: with high-proficiency students significantly more likely than others to apply idea planning, feedback handling, and resource management and low-proficiency ones significantly more likely than others to engage in goal-setting. The qualitative results suggest that the practice of journaling raised studentsā awareness and may have contributed to an increase in their use of self-regulated writing strategies. In particular, the findings reveal how students internalized and reconstructed the various SRL processes taking place via writing reflective journals. For L2 educators using or considering using reflective journals, these findings contain fresh insights that could help them not only to increase their studentsā SRL levels, but also to provide more individualized SRL guidance.</p
Table_5_On a path to becoming more self-regulated: Reflective journalsā impact on Chinese English as a foreign language studentsā self-regulated writing strategy use.docx
A number of studies have confirmed the positive effect of writing reflective journals on L2 learning. However, the relationship between writing reflective journals and the use of self-regulated writing strategies remains unclear. To redress this knowledge gap, we assigned 38 Chinese English as a foreign language (EFL) students three journal-writing tasks in which they reflected on their writing processes and explored (1) the types of self-regulated writing strategies and changes to those strategies that the studentsā reflective journals documented; (2) how students with varied writing-proficiency levels differed in their use of self-regulated writing strategies; and (3) the effects of reflective-journal writing on studentsā self-perceived use of self-regulated writing strategies in particular, and on their L2 writing in general. Among the 19 kinds of strategies identified in 112 reflective-journal entries, only five (i.e., handling feedback, resource management, text processing, emotion regulation, and idea planning) were demonstrated relatively frequently. The use of seven strategies (i.e., self-monitoring and evaluation, idea planning, perspective change, emotional control, effort regulation, peer learning, and resource management) exhibited significant increases over time, especially during the second-half of the focal semester. In addition, our journal data highlighted individual variation in proficiency levels: with high-proficiency students significantly more likely than others to apply idea planning, feedback handling, and resource management and low-proficiency ones significantly more likely than others to engage in goal-setting. The qualitative results suggest that the practice of journaling raised studentsā awareness and may have contributed to an increase in their use of self-regulated writing strategies. In particular, the findings reveal how students internalized and reconstructed the various SRL processes taking place via writing reflective journals. For L2 educators using or considering using reflective journals, these findings contain fresh insights that could help them not only to increase their studentsā SRL levels, but also to provide more individualized SRL guidance.</p
Table_1_On a path to becoming more self-regulated: Reflective journalsā impact on Chinese English as a foreign language studentsā self-regulated writing strategy use.docx
A number of studies have confirmed the positive effect of writing reflective journals on L2 learning. However, the relationship between writing reflective journals and the use of self-regulated writing strategies remains unclear. To redress this knowledge gap, we assigned 38 Chinese English as a foreign language (EFL) students three journal-writing tasks in which they reflected on their writing processes and explored (1) the types of self-regulated writing strategies and changes to those strategies that the studentsā reflective journals documented; (2) how students with varied writing-proficiency levels differed in their use of self-regulated writing strategies; and (3) the effects of reflective-journal writing on studentsā self-perceived use of self-regulated writing strategies in particular, and on their L2 writing in general. Among the 19 kinds of strategies identified in 112 reflective-journal entries, only five (i.e., handling feedback, resource management, text processing, emotion regulation, and idea planning) were demonstrated relatively frequently. The use of seven strategies (i.e., self-monitoring and evaluation, idea planning, perspective change, emotional control, effort regulation, peer learning, and resource management) exhibited significant increases over time, especially during the second-half of the focal semester. In addition, our journal data highlighted individual variation in proficiency levels: with high-proficiency students significantly more likely than others to apply idea planning, feedback handling, and resource management and low-proficiency ones significantly more likely than others to engage in goal-setting. The qualitative results suggest that the practice of journaling raised studentsā awareness and may have contributed to an increase in their use of self-regulated writing strategies. In particular, the findings reveal how students internalized and reconstructed the various SRL processes taking place via writing reflective journals. For L2 educators using or considering using reflective journals, these findings contain fresh insights that could help them not only to increase their studentsā SRL levels, but also to provide more individualized SRL guidance.</p
Low-Temperature and High-Performance Vanadium-Based Aqueous Zinc-Ion Batteries
Aqueous
zinc-ion batteries have attracted attention due to their
low cost and high safety. Unfortunately, dendrite growth, hydrogen
evolution reactions, cathodic dissolution, and other problems are
more serious; not only that, but also the cathodic and anodic materialsā
lattices contract when the temperature drops, and charge transfer
and solid phase diffusion become slow, seriously aggravating dendrite
growth. At present, there are few studies on the low-temperature system,
and studies on retaining high specific capacity are even more rare.
Herein, ethylene glycol (EG) and manganese sulfate (MSO) are selected
as additives, and the manganese vanadate (MVO) cathode is used to
find a high-performance solution at low temperature. MVO can provide
higher specific capacity and better structural stability than MnO2 to adapt to a low-temperature environment. At the same time,
Mn2+ in MSO can produce a cationic shield covering the
initial zinc tip at an appropriate concentration to avoid the tip
effect and inhibit the dissolution of MVO. EG can not only reduce
the freezing point of the electrolyte but also promote the desolvation
of [Zn(H2O)6]2+. The synergistic
effect of the three elements prevents the dissolution equilibrium
of Mn2+ in MVO from fluctuating greatly due to the change
of temperature. Therefore, when we use [email protected] M MnSO4 +
2 M ZnSO4 (EG + 0.2Mn/2ZSO) electrolyte at ā30 Ā°C,
the Zn||Zn batteries which used this type of electrolyte can remain
350 h at 1 mA cmā2 without failure. The Zn||Cu batteries
can retain 100% Coulombic efficiency after more than 2000 cycles at
0.2 mA cmā2. The Zn||MVO battery can reach 231.13
mA h gā1 at its first cycle, and the capacity retention
rate is still above 85% after 1000 cycles, which is higher than that
of the existing low-temperature research system
Hierarchical Micron-Sized Mesoporous/Macroporous Graphene with Well-Tuned Surface Oxygen Chemistry for High Capacity and Cycling Stability LiāO<sub>2</sub> Battery
Nonaqueous LiāO<sub>2</sub> battery is recognized as one of the most promising energy storage
devices for electric vehicles due to its super-high energy density.
At present, carbon or catalyst-supporting carbon materials are widely
used for cathode materials of LiāO<sub>2</sub> battery. However,
the unique electrode reaction and complex side reactions lead to numerous
hurdles that have to be overcome. The pore blocking caused by the
solid products and the byproducts generated from the side reactions
severely limit the capacity performance and cycling stability. Thus,
there is a great need to develop carbon materials with optimized pore
structure and tunable surface chemistry to meet the special requirement
of LiāO<sub>2</sub> battery. Here, we propose a strategy of
vacuum-promoted thermal expansion to fabricate one micron-sized graphene
matrix with a hierarchical meso-/macroporous structure, combining
with a following deoxygenation treatment to adjust the surface chemistry
by reducing the amount of oxygen and selectively removing partial
unstable groups. The as-made graphene demonstrates dramatically tailored
pore characteristics and a well-tuned surface chemical environment.
When applied in LiāO<sub>2</sub> battery as cathode, it exhibits
an outstanding capacity up to 19 800 mA h g<sup>ā1</sup> and
is capable of enduring over 50 cycles with a curtaining capacity of
1000 mA h g<sup>ā1</sup> at a current density of 1000 mA g<sup>ā1</sup>. This will provide a novel pathway for the design
of cathodes for LiāO<sub>2</sub> battery
Low-Temperature and High-Performance Vanadium-Based Aqueous Zinc-Ion Batteries
Aqueous
zinc-ion batteries have attracted attention due to their
low cost and high safety. Unfortunately, dendrite growth, hydrogen
evolution reactions, cathodic dissolution, and other problems are
more serious; not only that, but also the cathodic and anodic materialsā
lattices contract when the temperature drops, and charge transfer
and solid phase diffusion become slow, seriously aggravating dendrite
growth. At present, there are few studies on the low-temperature system,
and studies on retaining high specific capacity are even more rare.
Herein, ethylene glycol (EG) and manganese sulfate (MSO) are selected
as additives, and the manganese vanadate (MVO) cathode is used to
find a high-performance solution at low temperature. MVO can provide
higher specific capacity and better structural stability than MnO2 to adapt to a low-temperature environment. At the same time,
Mn2+ in MSO can produce a cationic shield covering the
initial zinc tip at an appropriate concentration to avoid the tip
effect and inhibit the dissolution of MVO. EG can not only reduce
the freezing point of the electrolyte but also promote the desolvation
of [Zn(H2O)6]2+. The synergistic
effect of the three elements prevents the dissolution equilibrium
of Mn2+ in MVO from fluctuating greatly due to the change
of temperature. Therefore, when we use [email protected] M MnSO4 +
2 M ZnSO4 (EG + 0.2Mn/2ZSO) electrolyte at ā30 Ā°C,
the Zn||Zn batteries which used this type of electrolyte can remain
350 h at 1 mA cmā2 without failure. The Zn||Cu batteries
can retain 100% Coulombic efficiency after more than 2000 cycles at
0.2 mA cmā2. The Zn||MVO battery can reach 231.13
mA h gā1 at its first cycle, and the capacity retention
rate is still above 85% after 1000 cycles, which is higher than that
of the existing low-temperature research system
Partial correlation between <i>HIF3A</i> methylation and metabolic indicators adjusted for age and gender.
<p>Partial correlation between <i>HIF3A</i> methylation and metabolic indicators adjusted for age and gender.</p