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Using near miss data detected from non-accident information to analyse marine traffic risk can alleviate some of the limitations of accident-based methods. A model based on an arena for detecting scenes of near miss is proposed to detect comprehensively those ship encounters with potential collision risk. To eliminate the influence of data sampling frequency on the detection of scenes of near miss, a single near miss is defined as the whole progress of traffic state from the time the target ship sails into the arena of the subject ship to the time it leaves the arena of the subject ship. To research the geographical distribution characteristics of marine traffic risk, first, a statistical model for the scenes of near miss based on the water grid method is proposed, and then a macroscopic collision risk model based on near miss is developed. The geographical distribution characteristics of marine traffic risk in the Bohai Sea are analysed, and the water areas of high marine traffic risk are obtained. The findings can provide theoretical support for marine safety management.
The aim of this study was to explore the application of the flipped classroom approach in the training of Mass Casualty Triage (MCT) to medical undergraduate students.
In this study, 103 fourth-year medical students were randomly divided into a Flipped Classroom (FC) group (n = 51) and a Traditional Lecture-based Classroom (TLC) group (n = 52). A post-class quiz, simulated field triage (SFT) and feedback questionnaires were performed to assess both groups of students for their learning of the course.
In the post-quiz, the median (IQR) scores achieved by students from the FC and TLC groups were 42(5) and 39(5.5), respectively. Significant differences were found between the two groups. In the SFT, overall triage accuracy was 67.06% for FC, and 64.23% for TLC students. Over-triage and under-triage errors occurred in 18.43% and 14.50% of the FC group, respectively. The TLC group had a similar pattern of 20.77% over-triage and 15.0% under-triage errors. No significant differences were found regarding overall triage accuracy or triage errors between the two groups.
The FC approach could enhance course grades reflected in the post-quiz and improve students’ satisfaction with the class. However, there was no significant difference of competency between the two groups demonstrated in the SFT exercise.
Building on past reviews on affect research (e.g. Akinola, 2010; Ashkanasy & Dorris, 2017; Larsen & Fredrickson, 1999; Mauss & Robinson, 2009; Peterson, Reina, Waldman, & Becker, 2015), in this chapter we review existing quantitative methods to measure workplace affect and affect regulation, and propose directions for future development in quantitative measurement of these processes. We endorse that affect is a multifaceted, dynamic process comprised of psychological and physiological experiences that informs thought and motivates action (Izard, 2009). Affect can be understood as a trait (general tendency to experience positive or negative feelings) or a state (momentary emotions in response to certain events). Consistent with the rest of this handbook, we use “affect” as an umbrella term that encompasses emotion, feeling, and other related terms.
Dolostones are widely developed in the middle Permian rocks of East Yunnan, China, mainly in the shoal-facies Maokou Formation. The previously reported dolostone formation mechanisms cannot explain the distribution and geochemical characteristics of these dolostones, in particular their strontium, magnesium and oxygen isotope signatures. To help predict the distribution of dolostone reservoirs and reduce the exploration risk and cost, this study proposes a new model of dolomitization: open thermal convection dolomitization. In this new dolomitization model, Mg2+ in dolomitizing fluids originates mostly from seawater, with a minor component coming from deep hydrothermal fluids. Elevated heat flux (in this case due to the nearby Emei mantle plume) causes spatial temperature variations in the fluid along the circulation flow pathways, resulting in fast and pervasive dolomitization of limestone. The proposed model not only explains the characteristics and distribution of dolostones in the study area but also serves as a reference for predicting the distribution of dolostones in other areas subjected to thermal convection.
A solution to the problem of Gaussian beam scattering by a circular perfect electric conductor coated with eccentrically anisotropic media is presented. The incident Gaussian beam source is expanded as an approximate expression in the simple form with Taylor's series. The transmitted field in the anisotropically coated region is expressed as an infinite summation of Eigen plane waves with different polar angles. The unknown coefficients of the scattered fields are obtained with the aid of the boundary conditions. The addition theorem for cylindrical functions is applied to transfer from the local coordinates to the global ones. The infinite series can be truncated under the prerequisite of achieving the solution convergence. Only the case of transverse-electric polarization is discussed. The similar formulation of transverse-magnetic polarization can be obtained by adopting a similar method. Some numerical results are presented and discussed. The result is in agreement with that available as expected when the eccentric geometry comes to the concentric one.
Social anxiety disorder (SAD) is a prevalent mental disorder diagnosed in childhood and adolescence. Theories regarding brain development and SAD suggest a close link between neurodevelopmental dysfunction at the adolescent juncture and SAD, but direct evidence is rare. This study aims to examine brain structural abnormalities in adolescents with SAD.
High-resolution T1-weighted images were obtained from 31 adolescents with SAD (15–17 years) and 42 matching healthy controls (HC). We evaluated symptom severity with the Social Anxiety Scale for Children (SASC) and the Screen for Child Anxiety Related Emotional Disorders (SCARED). We used voxel-based morphometry analysis to detect regional gray matter volume abnormalities and structural co-variance analysis to investigate inter-regional coordination patterns.
We found significantly higher gray matter volume in the orbitofrontal cortex (OFC) and the insula in adolescents with SAD compared to HC. We also observed significant co-variance of the gray matter volume between the OFC and amygdala, and the OFC and insula in HC, but these co-variance relationships diminished in SAD.
These findings provide the first evidence that the brain structural deficits in adolescents with SAD are not only in the core regions of the fronto-limbic system, but also represented by the diminished coordination in the development of these regions. The delayed and unsynchronized development pattern of the fronto-limbic system supports SAD as an adolescent-sensitive developmental mental disorder.
Aiming at the influence of coupling coefficient variation on the output voltage of a high-power LCC-S topology inductively coupled power transfer (ICPT) system, a synchronous three-phase triple-parallel Buck converter is used as the voltage adjustment unit. The control method for the three-phase current sharing of synchronous three-phase triple-parallel Buck converter and the constant voltage output ICPT system under the coupling coefficient variation is studied. Firstly, the hybrid model consisting of the circuit averaging model of the three-phase triple-parallel Buck converter and the generalized state-space average model for the LCC-S type ICPT system is established. Then, the control methods for three-phase current sharing of the synchronous three-phase triple-parallel Buck converter and constant voltage output of ICPT system are studied to achieve the multi-objective integrated control of the system. Finally, a 3.3 kW wireless charging system platform is built, the experimental results have verified the effectiveness of the proposed modeling and control method, and demonstrated the stability of the ICPT system.
The pathophysiology of obsessive-compulsive disorder (OCD) remains unclear despite extensive neuroimaging work on the disorder. Exposure to medication and comorbid mental disorders can confound the results of OCD studies. The goal of this study was to explore differences in brain functional connectivity (FC) within the cortico-striato-thalamo-cortical (CSTC) loop of drug-naïve and drug-free OCD patients and healthy controls (HCs).
A total of 29 drug-naïve OCD patients, 22 drug-free OCD patients, and 25 HCs matched on age, gender and education level underwent functional magnetic resonance imaging scanning at resting state. Seed-based connectivity analyses were conducted among the three groups. The Yale Brown Obsessive Compulsive Scale and clinical inventories were used to assess the clinical symptoms.
Compared with HCs, the drug-naïve OCD patients had reduced FC within the limbic CSTC loop. In the drug-naïve OCD participants, we also found hyperconnectivity between the supplementary motor area and ventral and dorsal putamen (p < 0.05, corrected for multiple comparisons).
Exposure to antidepressants such as selective serotonin reuptake inhibitors may affect the function of some brain regions. Future longitudinal studies could help to reveal the pharmacotherapeutic mechanisms in these loops.
A 15-year-old teenager presented with a 2-month history of headache. Neurological examination was normal except for papilledema. Further lumbar puncture indicated intracranial hypertension (330 mm H2O). Brain magnetic resonance imaging (MRI) was normal but phase contrast-magnetic resonance venography (PC-MRV) (Figure 1(A)) suggested possible left transverse-sigmoid sinus thrombosis; subsequent contrast-enhanced 3D fat-saturated T1 volumetric isotropic turbo spin echo acquisition (VISTA) MRI (Figure 1(B)) confirmed the pathology. Hyper-coagulable panel results (including six steroid sex hormones, antithrombin III, protein C, protein S, lupus anticoagulant, and anticardiolipin antibodies) were all within normal range. In further examination, computed tomography (CT) venography images (Figure 1(C) and (D)) showed that the left jugular vein was compressed by the styloid process, consistent with Eagle syndrome.1 The patient who refused the recommended surgical treatment, however, chose anticoagulant therapy consisting of low-molecular weight heparin subcutaneous injection in addition to new oral anticoagulant. At 18-month follow-up, the patient reported no symptoms remained.
Direct numerical simulation is conducted to uncover the response of a supersonic turbulent boundary layer to streamwise concave curvature and the related physical mechanisms at a Mach number of 2.95. Streamwise variations of mean flow properties, turbulence statistics and turbulent structures are analysed. A method to define the boundary layer thickness based on the principal strain rate is proposed, which is applicable for boundary layers subjected to wall-normal pressure and velocity gradients. While the wall friction grows with the wall turning, the friction velocity decreases. A logarithmic region with constant slope exists in the concave boundary layer. However, with smaller slope, it is located lower than that of the flat boundary layer. Streamwise varying trends of the velocity and the principal strain rate within different wall-normal regions are different. The turbulence level is promoted by the concave curvature. Due to the increased turbulence generation in the outer layer, secondary bumps are noted in the profiles of streamwise and spanwise turbulence intensity. Peak positions in profiles of wall-normal turbulence intensity and Reynolds shear stress are pushed outward because of the same reason. Attributed to the Görtler instability, the streamwise extended vortices within the hairpin packets are intensified and more vortices are generated. Through accumulations of these vortices with a similar sense of rotation, large-scale streamwise roll cells are formed. Originated from the very large-scale motions and by promoting the ejection, sweep and spanwise events, the formation of large-scale streamwise roll cells is the physical cause of the alterations of the mean properties and turbulence statistics. The roll cells further give rise to the vortex generation. The large number of hairpin vortices formed in the near-wall region lead to the improved wall-normal correlation of turbulence in the concave boundary layer.
The aim of this article was to investigate the mechanism of appetite suppression induced by high-fat diets (HFD) in blunt snout bream (Megalobrama amblycephala). Fish (average initial weight 40·0 (sem 0·35) g) were fed diets with two fat levels (6 and 11 %) with four replicates. HFD feeding for 30 d could significantly increase the weight gain rate, but feeding for 60 d cannot. Food intake of M. amblycephala began to decline significantly in fish fed the HFD for 48 d. HFD feeding for 60 d significantly reduced the expression of neuropeptide Y and elevated the expression of cocaine- and amphetamine-regulated transcript (CART), actions both in favour of suppression of appetite. The activation of fatty acid sensing was partly responsible for the weakened appetite. In addition, inflammatory factors induced by the HFD may be involved in the regulation of appetite by increasing the secretion of leptin and then activating the mammalian target of rapamycin (mTOR). Lipopolysaccharide (LPS, 2·0 mg/kg of fish weight) was administered to induce inflammation, and sampling was performed after 3, 6, 9, 12, 18, 24 and 48 h of LPS injection. Within 6–24 h of LPS injection, the food intake and appetite of M. amblycephala decreased significantly, whereas the mRNA expression of leptin and mTOR increased significantly. Our results indicate that inflammatory cytokines may be the cause of appetite suppression in M. amblycephala fed a HFD.
The strong interactions between Mg and Ni/NiH4 are attributed to harsh operating conditions and difficulties for H2 release, restricting the practical applications of the Mg-based hydrides. In this study, a new method of interstitial nonmetals co-doping was proposed to reduce the strong interactions. The calculation results showed that the method of interstitial nonmetals co-doping causes a more significant reduction in the thermal stability of Mg-based hydrides, as compared with the methods of either single transition metal or nonmetal doping. To determine the influence mechanism, a theoretical study was conducted based on the first-principles calculations. The computations demonstrated that the criss-cross action between B–Ni and N–Mg bonds weakens the bonding effects between Mg and Ni/NiH4. Besides, the mutual interactions between nonmetals and H atoms could weaken Ni–H bonding effects and stimulate the breaking of stable NiH4 clusters, thereby facilitating the release of H2 from the hydride.
Chitooligosaccharides (COS) are multi-functional foods and nutrients and environmentally friendly biological abiotic-resistance inducing agents for plants. In the current study, the effects and possible mechanisms of COS on improving the cold resistance of rice (II YOU 1259) seedlings were investigated. Compared with the control, a COS pre-soaking treatment enhanced photosynthesis, reduced oxidation damage and led to accumulation of more osmotic regulation substances under chilling treatment. In addition, a novel Deg/HtrA family serine endopeptidase (DegQ) gene, related to COS enhanced rice cold resistance, was identified. Quantitative real-time polymerase chain reaction (qRT-PCR) analysis revealed that transcription of DegQ and psbA (D1 protein encoding gene) were up-regulated in a time-dependent manner by COS treatment under cold stress. With increasing expression of the D1 protein, chlorophyll b content was enhanced correspondingly. The current results suggest that COS could enhance cold stress tolerance of rice by repairing the photodamaged photosystem II, altering osmotic regulation and reducing oxidation damage.
The antennal sensilla of female Quadrastichus mendeli Kim & La Salle (Hymenoptera: Eulophidae: Tetrastichinae) were observed with scanning and transmission electron microscopy in this study. The antenna of Q. mendeli was geniculate, and the flagellum was composed of seven subsegments. Six distinct types of sensory receptors were observed, including sensilla basiconic capitate peg, sensilla böhm, sensilla chaetica, sensilla campaniformia, sensilla placodea and sensilla trichodea. Sensilla basiconic capitate pegs were found on the flagellomeres, and Böhm sensilla were found on the basal part of scape and the pedicel. Two morphological subtypes of sensilla chaetica were found on the antennae, and sensilla campaniformia were only found on the pedicel. Sensilla placodea were divided into two morphological subtypes that were found on the flagellomeres. Sensilla trichodea were found on the 2nd–6th flagellomere. By comparison to existing antennal sensilla, it was found that sensilla basiconic capitate peg, sensilla chaetica, sensilla placodea and sensilla trichodea were the most common sensilla of the parasitoids of Eulophidae. The external and internal morphology, types, number, distribution, length, and width of these sensilla were described, and their possible functions are discussed in conjunction with the host-detection behavior. Future studies on the host location mechanisms in Q. mendeli will be facilitated by these observations.
The role of the cerebellum in obsessive-compulsive disorder (OCD) has drawn increasing attention. However, the functional connectivity between the cerebellum and the cerebral cortex has not been investigated in OCD, nor has the relationship between such functional connectivity and clinical symptoms.
A total of 27 patients with OCD and 21 healthy controls (HCs) matched on age, sex and education underwent magnetic resonance imaging (MRI). Seed-based connectivity analyses were performed to examine differences in cerebellar-cerebral connectivity in patients with OCD compared with HCs. Associations between functional connectivity and clinical features in OCD were analyzed.
Compared with HCs, OCD patients showed significantly decreased cerebellar-cerebral functional connectivity in executive control and emotion processing networks. Within the OCD group, decreased functional connectivity in an executive network spanning the right cerebellar Crus I and the inferior parietal lobule was positively correlated with symptom severity, and decreased connectivity in an emotion processing network spanning the left cerebellar lobule VI and the lingual gyrus was negatively correlated with illness duration.
Altered functional connectivity between the cerebellum and cerebral networks involved in cognitive-affective processing in patients with OCD provides further evidence for the involvement of the cerebellum in the pathophysiology of OCD, and is consistent with impairment in executive control and emotion regulation in this condition.
Environmental characteristics (for example, temperature, photoperiod) as seasonal cues can affect the offspring sex ratio and reproductive tactics of many hymenopteran insects. Leptocybe invasa Fisher & La Salle is the most critical invasive insect pest of Eucalyptus spp. in the world and displays thelytokous reproduction. In the current study, we studied the effects of temperature and photoperiod on offspring sex ratio and reproductive tactics in L. invasa. Results show that sex ratio (female: male) of L. invasa was under 15, 25 and 35 °C with both L 12: D 12 and L 16: D 8, and cold and thermal acclimation were 74.5:1, 71.0:1, 59.0:0, 17.3:1, 53.0:0, 64.0:0, 47.0:1 and 56.0:0, respectively, which was highly significantly female biased and with no significant difference due to temperature or photoperiod. Offspring virgin females oviposited and induced the bump-shaped galls on plants under the same conditions as described above. Constant temperature, photoperiod and their interaction, and cold and thermal acclimation had no significant effect on the infestation rates of Eucalyptus branches induced by offspring virgin females. Thus, temperature, photoperiod and cold and thermal acclimation did not influence female-biased sex ratio and tactics with thelytokous reproduction of offspring females in L. invasa.
Conservation plans for waterbirds in periodically flooded wetlands should be based on a deep understanding of the relationship between habitat availability and the hydrological regime. Using waterbird surveys and remotely sensed images, we investigated how habitat availability for wintering waterbirds was regulated by seasonal water level fluctuation at Shengjin Lake in the lower Yangtze River floodplain, which is an important wintering area along the East Asian-Australasian Flyway. We recorded 52 waterbird species during three field surveys, and categorised them into four groups based on their foraging preferences: grassland, mudflats, shallow water, or deep water. Habitat availability for the four groups was significantly influenced by fluctuations in water level. Habitat for deep-water feeders dominated the lake throughout the year, despite contracting during the wintering season. Water recession during winter exposed more diverse riparian habitats that showed high spatial heterogeneity at the landscape level, with the Upper Lake providing the most suitable habitats for the most diverse and abundant waterbirds. It is worth noting that the water level was regulated highly for aquaculture during the early wintering period, impeding access to suitable habitats for the early-arriving waterbirds that foraged in the riparian mudflats and grassland. Furthermore, rapid water recession from the opening of a sluice gate allowed the exposed moist mudflats to dry up quickly, reducing its suitability for shorebirds and cranes. For effective wintering waterbird conservation in the ephemeral lacustrine wetlands in the Yangtze River floodplain, we suggest stepwise water recession plans, together with the recovery of the aquatic vegetation community and reduction in high-density aquaculture, to synchronise the exposure of foraging habitats with the migration phenology of different waterbird species.
The Luziyuan Pb–Zn skarn deposit, located in the Baoshan–Narong–Dongzhi block metallogenic belt in SW China, is hosted by marble and slate in the upper Cambrian Shahechang Formation. Three skarn zones have been identified from the surface (1495 m above sea level (asl)) to a depth of 1220 m asl: zone 1 consists of chlorite–actinolite–calcite–quartz, zone 2 of rhodonite–actinolite–fluorite–quartz–calcite, and zone 3 contains garnet–rhodonite–actinolite–fluorite–quartz–calcite. The deposit formed in four distinct mineralization stages: an early anhydrous skarn (garnet, rhodonite and bustamite) stage (Stage 1), a hydrous skarn (actinolite and chlorite) stage (Stage 2), an early quartz (coarse barren quartz veins) stage (Stage 3) and a late sulphide-forming (fine sulphide-bearing quartz veins) stage (Stage 4). The Stage 1 skarn-forming fluid temperature was at least 500 °C according to the geothermometer with rhodonite/bustamite trace elements measured by laser ablation – inductively coupled plasma – mass spectrometry (LA-ICP-MS). A decrease in ore fluid temperatures with time is consistent with the decreases in the δ18Ofluid and δDfluid values from Stage 3 to 4. This trend suggests that the ore fluid was mainly derived from magmatic water and mixed with large amounts of meteoric water during mineralization. The δ34S values of Stage 4 chalcopyrite, sphalerite and galena are similar to those of an Ordovician gypsum layer, and together with the high-salinity fluids in Stage 4 indicate the dissolution of evaporites in the Luziyuan region. Overall, the results of this study suggest that the Luziyuan deposit is a distal Pb–Zn skarn deposit that formed in response to multi-stage alteration associated with a combination of magmatic water and meteoric water.
The present study examines the characteristics of clay minerals in shale gas reservoirs and their influence on reservoir properties based on X-ray diffraction and scanning electron microscopy. These analyses were combined with optical microscopy observations and core and well-log data to investigate the genesis, distribution characteristics, main controlling factors and pore features of clay minerals of the Lower Silurian Longmaxi Formation in the East Sichuan area, China. The clay mineral assemblage consists of illite + mixed-layer illite-smectite (I-S) + chlorite. This assemblage includes three sources of clay minerals: detrital, authigenic and diagenetic minerals. The lower section of the Longmaxi Formation in the Jiaoshiba area has sealing ability which resulted in abnormal high pressures during hydrocarbon generation which inhibited illitization. Therefore, an anomalous transformation sequence is present in which the mixed-layer I-S content increases with depth. This anomalous transformation sequence can be used to infer the existence of abnormal high pressures. The detrital components of the formation also affect the clay-minerals content indirectly, especially the abundance of K-feldspar. The transformation of mixed-layer I-S to illite is limited due to the limited availability of K+, which determines the extent of transformation. Three types of pores were observed in the shale reservoir rocks of the Longmaxi Formation: interparticle (interP) pores, intraparticle (intraP) pores and organic-matter pores. The clay-mineral content controls the development of intraP pores, which are dominated by pores within clay particles. For a given clay mineral content, smectite and mixed-layer I-S were more conducive to the development of shale-gas reservoirs than other clay minerals.