Guiding of relativistically intense laser pulses with peak power of 0.85 PW over 15 diffraction lengths was demonstrated by increasing the focusing strength of a capillary discharge waveguide using ...laser inverse bremsstrahlung heating. This allowed for the production of electron beams with quasimonoenergetic peaks up to 7.8 GeV, double the energy that was previously demonstrated. Charge was 5 pC at 7.8 GeV and up to 62 pC in 6 GeV peaks, and typical beam divergence was 0.2 mrad.
In this study, an augmented reality-based mobile learning system is proposed for conducting inquiry-based learning activities. An experiment has been conducted to examine the effectiveness of the ...proposed approach in terms of learning achievements and motivations. The subjects were 57 fourth graders from two classes taught by the same teacher in an elementary school in northern Taiwan. The experimental results showed that the proposed approach is able to improve the students' learning achievements. Moreover, it was found that the students who learned with the augmented reality-based mobile learning approach showed significantly higher motivations in the attention, confidence, and relevance dimensions than those who learned with the conventional inquiry-based mobile learning approach.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This study developed a 5-step vocabulary learning (FSVL) strategy and a mobile learning tool in a situational English vocabulary learning environment and assessed their effects on the learning ...motivation and performance of English as a foreign language (EFL) students in a situational English vocabulary learning environment. Overall, 80 EFL students and 1 teacher participated in this study. Two learning methods were implemented. The first involved employing the FSVL strategy and the mobile learning tool in a situational English vocabulary learning environment, and the other method involved employing the FSVL strategy and traditional learning tools in a situational English vocabulary learning environment. Data were collected by conducting interviews and tests and administering the Attention, Relevance, Confidence, and Satisfaction motivation questionnaire. The results showed that the learning motivation and performance of students taught using the FSVL strategy and mobile learning tool were superior to those of students taught using the FSVL strategy and traditional learning tools in a situational English vocabulary learning environment.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NMLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The East Asian summer monsoon is unique among summer monsoon systems in its complex seasonality, exhibiting distinct intraseasonal stages. Previous studies have alluded to the downstream influence of ...the westerlies flowing around the Tibetan Plateau as key to its existence. We explore this hypothesis using an atmospheric general circulation model that simulates the intraseasonal stages with fidelity. Without a Tibetan Plateau, East Asia exhibits only one primary convective stage typical of other monsoons. As the plateau is introduced, the distinct rainfall stages—spring, pre-mei-yu, mei-yu, and midsummer—emerge, and rainfall becomes more intense overall. This emergence coincides with a pronounced modulation of the westerlies around the plateau and extratropical northerlies penetrating northeastern China. The northerlies meridionally constrain the moist southerly flow originating from the tropics, leading to a band of lower-tropospheric convergence and humidity front that produces the rainband. The northward migration of the westerlies away from the northern edge of the plateau leads to a weakening of the extratropical northerlies, which, coupled with stronger monsoonal southerlies, leads to the northward migration of the rainband. When the peak westerlies migrate north of the plateau during the midsummer stage, the extratropical northerlies disappear, leaving only the monsoon low-level circulation that penetrates northeastern China; the rainband disappears, leaving isolated convective rainfall over northeastern China. In short, East Asian rainfall seasonality results from the interaction of two seasonally evolving circulations—the monsoonal southerlies that strengthen and extend northward, and the midlatitude northerlies that weaken and eventually disappear—as summer progresses.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Phytochemicals have been used as potential chemopreventive or chemotherapeutic agents. However, there are data suggesting a mutagenic effect of some phytochemicals. We hypothesized that safrole would ...have anticancer effects on human oral squamous cell carcinoma HSC-3 cells. Safrole decreased the percentage of viable HSC-3 cells via induction of apoptosis by an increased level of cytosolic Ca2+ and a reduction in the mitochondrial membrane potential (ΔΨ
m
). Changes in the membrane potential were associated with changes in the Bax, release of cytochrome c from mitochondria, and activation of downstream caspases-9 and -3, resulting in apoptotic cell death. In vivo studies also showed that safrole reduced the size and volume of an HSC-3 solid tumor on a xenograft athymic nu/nu mouse model. Western blotting and flow cytometric analysis studies confirmed that safrole-mediated apoptotic cell death of HSC-3 cells is regulated by cytosolic Ca2+ and by mitochondria- and Fas-dependent pathways.
Abstract
Zoonotic transfer of animal pathogens to human hosts can generate novel agents, but the genetic events following such host jumps are not well studied. Here we characterize the mechanisms ...driving adaptive evolution of the emerging zoonotic pathogen
Bordetella hinzii
in a patient with interleukin-12 receptor β1 deficiency. Genomic sequencing of 24
B. hinzii
isolates cultured from blood and stool over 45 months revealed a clonal lineage that had undergone extensive within-host genetic and phenotypic diversification. Twenty of 24 isolates shared an E9G substitution in the DNA polymerase III ε-subunit active site, resulting in a proofreading deficiency. Within this proofreading-deficient clade, multiple lineages with mutations in DNA repair genes and altered mutational spectra emerged and dominated clinical cultures for more than 12 months. Multiple enzymes of the tricarboxylic acid cycle and gluconeogenesis pathways were repeatedly mutated, suggesting rapid metabolic adaptation to the human environment. Furthermore, an excess of G:C > T:A transversions suggested that oxidative stress shaped genetic diversification during adaptation. We propose that inactivation of DNA proofreading activity in combination with prolonged, but sub-lethal, oxidative attack resulting from the underlying host immunodeficiency facilitated rapid genomic adaptation. These findings suggest a fundamental role for host immune phenotype in shaping pathogen evolution following zoonotic infection.
Abstract
A recent hypothesis holds that changes to the East Asian summer rainfall are characterized by changes in the timing and duration of its intraseasonal stages, controlled by the meridional ...position of the westerlies relative to the Tibetan Plateau. This hypothesis is examined in the context of the leading mode of East Asian summer (July–August) rainfall. One phase of this “tripole” mode—characterized by less rainfall over central eastern China and increased rainfall over northeastern and southeastern China—is tied to an earlier termination of Meiyu that results in a significantly shorter Meiyu and longer Midsummer stage. This phase also exhibits an earlier northward transition of the westerlies to the north of the Plateau, essentially mirroring the changes to precipitation seasonality. The reverse does not hold true for the opposite phase. Our results show direct observational evidence for the meridional position of the westerlies to control East Asian summer monsoon seasonality.
Key Points
Leading mode of July‐August East Asian rainfall variability caused by changes in timing of Meiyu termination and duration of Meiyu/Midsummer
Changes to timing and duration associated with variation in the meridional migration of westerlies relative to the Tibetan Plateau
Results show direct observational evidence for meridional position of westerlies to control East Asian summer monsoon seasonality
Background
Childhood asthma comprises different phenotypes with complex pathophysiology. Different asthma phenotypes evoke various clinical symptoms and vary in their responses to treatments.
Methods
...We applied k‐means clustering algorithm of twelve objective laboratory tests among 351 asthmatic children enrolled in the Taiwanese Consortium of Childhood Asthma Study (TCCAS). We constructed gene expression profiles of peripheral blood mononuclear cells (PBMC) from children with different asthma phenotypes.
Results
Five distinct phenotypes of childhood asthma were identified and can be characterized by either eosinophil‐predominant or neutrophil‐predominant inflammatory characteristics. In the gene expression profile analysis, significant differences were noted for neutrophil‐predominant asthma, compared with samples from all the other asthma phenotypes. The vast majority of the differentially expressed genes in neutrophil‐predominant asthma was associated with corticosteroid response. From an independent inhaled corticosteroid (ICS) response cohort, we also found neutrophils could be activated in this severe asthma phenotype and neutrophil‐predominant asthma may be associated with corticosteroid nonresponsiveness.
Conclusion
Phenotype clustering of childhood asthma can be helpful to identify clinically relevant patients and reveal different inflammatory characteristics in asthmatic children. Neutrophil‐predominant asthma is the most severe asthma phenotype with poor corticosteroid response. Gene expression profile of different asthma phenotypes not only improve our knowledge of childhood asthma, but also can guide asthma precision medicine.
Neutrophil‐predominant asthma is the most severe asthma phenotype with poor corticosteroid response. Five distinct phenotypes of childhood asthma identified in this study with differences in lung function, symptom frequency, healthcare utilization, percentages of eosinophils and neutrophils in peripheral blood, and serum IgE. Gene expression signature in PBMC constitutes an easier way to objectively identify corticosteroid‐resistant asthma in clinical settings.
Summary
We investigated the association between fasting plasma glucose variability (FPG-CV) and the risk of hip fracture in elderly diabetic patients. Our finding showed a temporal association ...between FPG-CV and hip fracture as patients categorized as FPG-CV greater than 25.4 % showed an increased risk in hip fractures.
Introduction
Hip fracture is a major health burden in the population and is associated with high rates of mortality and morbidity especially in elderly. It is evident that diabetes mellitus is a risk factor of osteoporosis which is a significant risk factor of hip fracture. However, epidemiological studies exploring the risks of hip fracture among type 2 diabetic patients are limited.
Methods
A retrospective study of 26,501 ethnic Chinese older persons enrolled in the National Diabetes Care Management program in Taiwan was conducted; related factors were analyzed with extended Cox proportional hazards regression models to competing risk data on hip fracture incidence.
Results
The results show a temporal association between FPG-CV and hip fracture as patients categorized as FPG-CV greater than 25.4 % showed an increased risk in hip fractures, confirming a linear relationship between the two. After multivariate adjustment, the risk of hip fracture increased among patients with FPG-CV of 25.4–42.3 % and >42.3 % compared with patients with FPG-CV of ≦ 14.3 % (hazard ratio, 1.35; 95 % confidence interval 1.14–1.60 and 1.27; 1.07–1.52, respectively). Significant linear trends among various FPG-CV were observed.
Conclusions
Thus, the present study demonstrated the importance of glucose stability for fracture prevention in older persons with type 2 diabetes. Future studies should be conducted to explore whether reduction in glucose oscillation in older adults with diabetes mellitus can reduce the risk of hip fracture.
An ideal material has yet to be discovered that can completely treat dentin hypersensitivity; however, calcium phosphate precipitation has exhibited potential value for the treatment of dentin ...hypersensitivity by the occlusion of dentinal tubules. We hypothesized that a novel mesoporous silica biomaterial (nano CaO@mesoporous silica, NCMS) containing nano-sized calcium oxide particles mixed with 30% phosphoric acid can efficiently occlude dentinal tubules and significantly reduce dentin permeability, even with the presence of pulpal pressure. This highly supersaturated Ca2+-and HPO4
2−ion-containing NCMS paste was brushed onto dentin surfaces, and the ions diffused deeply into the dentinal tubules and formed a CaHPO4·2H2O precipitation with a depth of 100 μm. The results of the dentin permeability tests showed that the novel mesoporous material exhibited a significant reduction in dentin permeability (p < 0.05), even under simulated pulpal pressure, as compared with our previously developed material, DP-bioglass, and a commercial desensitizing material, Seal & Protect®.
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