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This manuscript discusses the challenges in detecting and attributing recently observed trends in the Atlantic tropical cyclone (TC) and the epistemic uncertainty we face in assessing future risk. We use synthetic storms downscaled from five CMIP5 models by the Columbia HAZard model (CHAZ), and directly simulated storms from high-resolution climate models. We examine three aspects of recent TC activity: the upward trend and multi-decadal oscillation of the annual frequency, the increase in storm wind intensity, and the decrease in forward speed. Some data sets suggest that these trends and oscillation are forced while others suggest that they can be explained by natural variability. Projections under warming climate scenarios also show a wide range of possibilities, especially for the annual frequencies, which increase or decrease depending on the choice of moisture variable used in the CHAZ model and on the choice of climate model. The uncertainties in the annual frequency lead to epistemic uncertainties in TC risk assessment. Here, we investigate the potential for reduction of these epistemic uncertainties through a statistical practice, namely likelihood analysis. We find that historical observations are more consistent with the simulations with increasing frequency than those with decreasing frequency, but we are not able to rule out the latter. We argue that the most rational way to treat epistemic uncertainty is to consider all outcomes contained in the results. In the context of risk assessment, since the results contain possible outcomes in which TC risk is increasing, this view implies that the risk is increasing.

The authors describe a tropical cyclone risk model for the Philippines using open-source methods that can be straightforwardly generalized to other countries. Wind fields derived from historical observations, as well as those from an environmentally forced tropical cyclone hazard model, are combined with data representing exposed value and vulnerability to determine asset losses. Exposed value is represented by the LitPop dataset, which assumes total asset value is distributed across a country following population density and night-lights data. Vulnerability is assumed to follow a functional form previously proposed by Emanuel, with free parameters chosen by a sensitivity analysis in which simulated and historical reported damages are compared for different parameter values and further constrained by information from household surveys about regional building characteristics. Use of different vulnerability parameters for the region around Manila, Philippines, yields much better agreement between simulated and actually reported losses than does a single set of parameters for the entire country. Despite the improvements from regionally refined vulnerability, the model predicts no losses for a substantial number of destructive historical storms, a difference the authors hypothesize is due to the use of wind speed as the sole metric of tropical cyclone hazard, omitting explicit representation of storm surge and/or rainfall. Bearing these limitations in mind, this model can be used to estimate return levels for tropical cyclone-caused wind hazards and asset losses for regions across the Philippines, relevant to some disaster risk reduction and management tasks; this model also provides a platform for further development of open-source tropical cyclone risk modeling.

The authors describe a tropical cyclone risk model for the Philippines, using methods that are open-source and can be straightfor-wardly generalized to other countries. Wind fields derived from historical observations, as well as those from an environmentally forced tropical cyclone hazard model (using environmental forcing from the recent historical period) are combined with data representing exposed value and vulnerability to determine asset losses. Exposed value is represented by the LitPop dataset, which assumes total asset value is distributed across a country following population density and nightlights data. Vulnerability is assumed to follow a functional form previously proposed by Emanuel, with free parameters chosen by a sensitivity analysis in which simulated and historical reported damages are compared for different parameter values. Use of different vulnerability parameters for the region around Manila yields much better agreement between simulated and actually reported losses than does a single set of parameters for the entire country. Even then, however, the model predicts no losses for a substantial number of historical storms which did in fact produce them, a difference the authors hypothesize is at least in part due to the use of wind speed as the sole metric of TC hazard, omitting explicit representation of flooding due to storm surge and/or rainfall.

Studies have suggested that visually presented words are obligatorily decomposed into constituents that could be mapped to language representations. The present study aims to elucidate how orthographic processing of one constituent affects the other and vice versa during a word recognition task. Chinese orthographic system has characters representing syllables and meanings instead of suffixation roles, and the majority of Chinese characters are phonograms that can be further decomposed into phonetic radical and semantic radical. We propose that semantic radical combinability indexed by semantic radicals and the effect of phonological consistency indexed by phonetic radicals would interact with each other during the reading of Chinese phonograms. Twenty-six right-handed native Chinese speakers were recruited to the study. Participants were presented with phonograms divided into four conditions following their semantic radical combinability (large vs. small) and phonological consistency (high vs. low). EEG signals were recorded throughout the covert naming task. Our results show that there is an interaction effect between phonological consistency and semantic radical combinability on the right hemisphere N170 activity while reading phonograms. Semantic radical combinability influenced the right hemisphere N170 during the process of low-consistency character reading but not high-consistency character reading. On the other hand, the left hemisphere N170 revealed a more significant activity during reading high-consistency characters and was not affected by radical combinability. In addition, while low-consistency characters revealed a larger P200 than high-consistency characters, the semantic radical combinability effect on P200 was only significant when participants were reading high-consistency characters but not low-consistency characters. These results provide new information about how ERPs are involved in word recognition within the context of interaction among orthographic and phonological dimensions.

Purpose: This study explored the neural marker indexing deficits in discriminating lexical tone changes in Mandarin-speaking children with developmental language disorders (DLDs) using mismatch negativity, an event-related potential component for auditory change detection. Mandarin has four lexical tones characterized by a high-level tone (T1), high-rising tone (T2), low-dipping tone (T3), and high-falling tone (T4), in which the T2/T3 contrast is acoustically less discriminable in developmental groups. Therefore, this study further examined how deficits in children with DLD would vary with tonal contrasts' acoustic saliency. Method: Event-related potentials were measured using the multideviant oddball paradigm described by Lee et al. (2012), who used Mandarin syllables [i] in T3 as the standard sound (80%), T1 as the large deviant (10%), and T2 as the small deviant (10%). Twelve children with DLD aged between 4 and 6 years participated in this study, and 12 age-matched children with typical development were selected from the data set of Lee et al. (2012) as the controls. Results: The T1/T3 change elicited adultlike mismatch negativity in both the DLD and control groups, while no group difference was revealed. The T2/T3 change elicited a robust positive mismatch response (P-MMR) in children with DLD, while the P-MMR was less significant in the control group. The group comparisons revealed a larger P-MMR in children with DLD than in the control group. Furthermore, children with lower scores in language assessments tend to reveal larger P-MMRs. Conclusions: This study demonstrated that deficits in children with DLD in discriminating subtle lexical tone changes reflect greater positivity of P-MMR to T2/T3 change. This implies that MMR to T2/T3 may serve as a neural marker for evaluating language delay in preschoolers.

Innate behaviors are genetically encoded, but their underlying molecular mechanisms remain largely unknown. Predator odor 2,4,5-trimethyl-3-thiazoline (TMT) and its potent analog 2-methyl-2-thiazoline (2MT) are believed to activate specific odorant receptors to elicit innate fear/defensive behaviors in naive mice. Here, we conduct a large-scale recessive genetics screen of ethylnitrosourea (ENU)-mutagenized mice. We find that loss of Trpa1, a pungency/irritancy receptor, diminishes TMT/2MT and snake skin-evoked innate fear/defensive responses. Accordingly, Trpa1 -/- mice fail to effectively activate known fear/stress brain centers upon 2MT exposure, despite their apparent ability to smell and learn to fear 2MT. Moreover, Trpa1 acts as a chemosensor for 2MT/TMT and Trpa1-expressing trigeminal ganglion neurons contribute critically to 2MT-evoked freezing. Our results indicate that Trpa1-mediated nociception plays a crucial role in predator odor-evoked innate fear/defensive behaviors. The work establishes the first forward genetics screen to uncover the molecular mechanism of innate fear, a basic emotion and evolutionarily conserved survival mechanism.

Purpose: This study explored the neural marker indexing deficits in discriminating lexical tone changes in Mandarin-speaking children with developmental language disorders (DLDs) using mismatch negativity, an event-related potential component for auditory change detection. Mandarin has four lexical tones characterized by a high-level tone (T1), high-rising tone (T2), low-dipping tone (T3), and high-falling tone (T4), in which the T2/T3 contrast is acoustically less discriminable in developmental groups. Therefore, this study further examined how deficits in children with DLD would vary with tonal contrasts' acoustic saliency. Method: Event-related potentials were measured using the multideviant oddball paradigm described by Lee et al. (2012), who used Mandarin syllables [i] in t3 as the standard sound (80%), T1 as the large deviant (10%), and T2 as the small deviant (10%). Twelve children with DLD aged between 4 and 6 years participated in this study, and 12 age-matched children with typical development were selected from the data set of Lee et al. (2012) as the controls. Results: The T1/T3 change elicited adultlike mismatch negativity in both the DLD and control groups, while no group difference was revealed. The T2/T3 change elicited a robust positive mismatch response (P-MMR) in children with DLD, while the P-MMR was less significant in the control group. The group comparisons revealed a larger P-MMR in children with DLD than in the control group. Furthermore, children with lower scores in language assessments tend to reveal larger P-MMRs. Conclusions: This study demonstrated that deficits in children with DLD in discriminating subtle lexical tone changes reflect greater positivity of P-MMR to T2/T3 change. This implies that MMR to T2/T3 may serve as a neural marker for evaluating language delay in preschoolers., Language skill is essential for successful communication and knowledge acquisition in the modern society. Unfortunately, approximately 5%-10% of children had oral language development that is substantially and quantifiably below what [...]

This study used the lexicality effects on N400 to investigate orthographic processing in children with developmental dyslexia. Participants performed a Go/No-Go semantic judgment task; three types of stimuli--real characters (RC), pseudocharacters (PC), and noncharacters (NC)--were embedded in No-Go trials. Two types of lexicality effects (RC vs. NC and PC vs. NC) were used to reflect the sensitivity to Chinese orthographic knowledge. In typical developing children, NC elicited a more negative N400 in frontal sites and a less negative N400 in bilateral posterior sites than RC and PC. The reversed lexicality effects in anterior and posterior sites support the dual-mechanism for lexical retrieval. Children with dyslexia revealed a more negative N400 for NC in frontal sites compared with RC, suggesting that they remained sensitive to orthographic familiarity. However, no difference between NC and PC was observed, suggesting a weakness in capturing Chinese orthographic knowledge in children with dyslexia.

Using the Chinese writing system, which is unique with respect to the composition of each character in terms of its graphic shape, as an example, this chapter addresses the neurobiological underpinnings of reading and writing and how these brain circuits are used in different languages.