Contemporary Sediment Delivery Ratios for Small Catchments Subject to Shallow Rainfall Triggered Earthflows in the Waipaoa Catchment, North Island, New Zealand

<p>The Waipaoa catchment is generally considered to have high hill slope channel coupling due to the large volumes of sediment output at the river mouth. Yet the percentage of sediment that is transported within the fluvial system is low when considered in terms of the total volume of sediment mobilised during episodic failure events. Clearly, there is a discrepancy between generation of sediment and its delivery to the fluvial network. Previous research has suggested there is a strong decrease in catchment connectivity as catchment size increases. However, little research has been undertaken to understand the changes in hillslope-channel coupling over time. This study focuses on the connectivity of shallow rainfall triggered earthflows located in small catchments located within three different land systems in the Waipaoa Catchment. A multiple regression model was developed to predict the sediment delivery ratio for individual earthflows based on an empirical dataset of earthflows which occurred during a storm event in 2002. The results from this modelling were applied to five larger sub-catchments where sequential aerial photograph analysis (1940s to 2004) was used to determine connectivity. From this, spatial and temporal patterns in the catchment sediment delivery ratios were identified. The expected decrease in sediment delivery ratios was observed as catchment size increased. However, the temporal pattern to sediment delivery is not so clear. It appears that catchment evolution, referring specially to the Terrain Event Resistance Model developed by Crozier and Preston (1999), does not have a significant influence on sediment delivery ratios within the six decades examined in this thesis. Furthermore, while earthflows are considered the ultimate source of sediment during storm events, they are not always the mechanism by which this sediment enters the fluvial network. It is also vital to consider rates of gullying, sheet erosion and riparian erosion.</p>

Contemporary Sediment Delivery Ratios for Small Catchments Subject to Shallow Rainfall Triggered Earthflows in the Waipaoa Catchment, North Island, New Zealand

<p>The Waipaoa catchment is generally considered to have high hill slope channel coupling due to the large volumes of sediment output at the river mouth. Yet the percentage of sediment that is transported within the fluvial system is low when considered in terms of the total volume of sediment mobilised during episodic failure events. Clearly, there is a discrepancy between generation of sediment and its delivery to the fluvial network. Previous research has suggested there is a strong decrease in catchment connectivity as catchment size increases. However, little research has been undertaken to understand the changes in hillslope-channel coupling over time. This study focuses on the connectivity of shallow rainfall triggered earthflows located in small catchments located within three different land systems in the Waipaoa Catchment. A multiple regression model was developed to predict the sediment delivery ratio for individual earthflows based on an empirical dataset of earthflows which occurred during a storm event in 2002. The results from this modelling were applied to five larger sub-catchments where sequential aerial photograph analysis (1940s to 2004) was used to determine connectivity. From this, spatial and temporal patterns in the catchment sediment delivery ratios were identified. The expected decrease in sediment delivery ratios was observed as catchment size increased. However, the temporal pattern to sediment delivery is not so clear. It appears that catchment evolution, referring specially to the Terrain Event Resistance Model developed by Crozier and Preston (1999), does not have a significant influence on sediment delivery ratios within the six decades examined in this thesis. Furthermore, while earthflows are considered the ultimate source of sediment during storm events, they are not always the mechanism by which this sediment enters the fluvial network. It is also vital to consider rates of gullying, sheet erosion and riparian erosion.</p>

Analysis of barrier distributions data for16O + 64Zn reaction at sub-barrier energies

The barrier distribution data for the 16O + 64Zn reaction at energies spanning around the no minal barrier are examined by employing symmetric-asymmetric Gaussian barrier distribution (SAGBD) approach. The cumulative role of dominant channel couplings in the SAGBD method are determined in terms of the channel coupling parameter λ and percentage decrease of fusion barrier VCBRED with reference to nominal Coulomb barrier. The non-zero and positive values of these parameters for the studied system quantitively measure the influences of dominant intrinsic channels originated from the structure of the participants. The barrier distribution data of 16O + 64Zn reaction is quantitatively as well as qualitatively explained by SAGBD outcomes.

The explanation of some exotic states in the $$cs{\bar{c}}{\bar{s}}$$ tetraquark system

Inspired by the recent observation of $$\chi _{c0}(3930)$$ χ c 0 ( 3930 ) , X(4685) and X(4630) by the LHCb Collaboration and some exotic resonances such as X(4350), X(4500), etc. by several experiment collaborations, the $$cs{\bar{c}}{\bar{s}}$$ c s c ¯ s ¯ tetraquark systems with $$J^{PC}=0^{++}$$ J PC = 0 + + , $$1^{++}$$ 1 + + , $$1^{+-}$$ 1 + - and $$2^{++}$$ 2 + + are systematically investigated in the framework of the quark delocalization color screening model(QDCSM). Two structures, the meson–meson and diquark–antidiquark structures, as well as the channel-coupling of all channels of these two configurations are considered in this work. The numerical results indicate that the molecular bound state $$D^{-}_{s}D_{s}^{+}$$ D s - D s + with $$J^{PC}=00^{++}$$ J PC = 00 + + can be supposed to explain the $$\chi _{c0}(3930)$$ χ c 0 ( 3930 ) . Besides, by using the stabilization method, several resonant states are obtained. Among these states, X(4350), X(4500) and X(4700) can be explained as the compact tetraquark states with $$J^{PC}=00^{++}$$ J PC = 00 + + , and the X(4274) is possible to be a candidate of the compact tetraquark state with $$J^{PC}=1^{++}$$ J PC = 1 + + . Apart from that, the $$J^{PC}=0^{++}$$ J PC = 0 + + resonance state with energy range 4028–4033 MeV, the two $$J^{PC}=2^{++}$$ J PC = 2 + + resonance states with energy range of 4394–4448 MeV and 4526–4536 MeV are possible to be new exotic states, which are indeed worthy of attention. More experimental tests are expected to check the existence of all these possible resonance states.

Clinical and genetic analysis of KATP variants with heart failure risk in patients with decreased serum ApoA-I levels

Context Lower serum concentration of apolipoprotein A-I (ApoA-I) is causally associated with heart failure (HF) risk. ATP-sensitive potassium channels (KATP), as a gating channel coupling vascular reactivity and metabolism with ischemic protection, become a new potential target of management for HF. The KATP gene sequence is highly polymorphic and high degree of genetic heterogeneity. Objective To determine whether ATP-sensitive potassium channels (KATP) variants predict the risks of decreased ApoA-I concentration and its related HF. Design, Patients, Settings A total of 634 subjects, including 317 subjects with decreased ApoA-I concentration (&lt; 120 mg/dL) and 317 counterpart subjects (≥ 120 mg/dL), were retrospectively selected. Methods 5 KATP variants were genotyped through MassARRAY platform. The exosome-derived microRNAs (exo-miRs) expression profiles were identified by next-generation sequencing, and the top 10 DE exo-miRs were verified using qPCR in a validation cohort of 240 subjects with decreased ApoA-I concentration. Results KATP rs141294036 was related to increased risk of lower ApoA-I levels (adjusted OR=1.95, P=0.002) and HF incidence (adjusted OR=2.38, P=0.009), especially HFpEF (adjusted OR=2.13, P=0.015). After median 48.6-months follow-up, participants carrying CC genotype of rs141294036 was associated with elevated HF re-hospitalization risk (adjusted HR=1.91, P=0.005). 36 exo-miRs were significantly differentially expressed between different genotypes of rs141294036 in subjects with lower ApoA-I levels, but only 5 exo-miRs (miR-31-5p, miR-126-5p, miR-106a-5p, miR-378i and miR-181c-5p) were further confirmed. Conclusions The KATP rs141294036 was associated with increased risks of lower ApoA-I levels, HF incidence (especially HFpEF) and HF re-hospitalization, involving in those 5 confirmed exo-miRs and its related metabolic pathways.

Recoupling mechanism for exotic mesons and baryons

The infinite chain of transitions of one pair of mesons (channel I) into another pair of mesons (channel II) can produce bound states and resonances in both channels even if no interactions inside channels exist. These resonances which can occur also in meson-baryon channels are called channel-coupling (CC) resonances. A new mechanism of CC resonances is proposed where transitions occur due to a rearrangement of confining strings inside each channel — the recoupling mechanism. The amplitude of this recoupling mechanism is expressed via overlap integrals of the wave functions of participating mesons (baryons). The explicit calculation with the known wave functions yields the peak at E = 4.12 GeV for the transitions $$ J/\psi +\phi \leftrightarrow {D}_s^{\ast }+{\overline{D}}_s^{\ast } $$ J / ψ + ϕ ↔ D s ∗ + D ¯ s ∗ , which can be associated with χc1 (4140), and a narrow peak at 3.98 GeV with the width 10 MeV for the transitions $$ {D}_s^{-}+{D}_0^{\ast}\leftrightarrow J/\psi +{K}^{\ast -} $$ D s − + D 0 ∗ ↔ J / ψ + K ∗ − , which can be associated with th recently discovered Zcs (3985).

Relationship between sediment connectivity and debris flow in a mountain catchment

&lt;p&gt;The hillslope-channel coupling has a fundamental role in sediment control of a catchment, especially when the catchment is prone to mass movements. Debris flow is a type of mass movements that provides an important sediment contribution to a channel, which is influenced by hillslope-channel coupling degree. This coupling can be represented by the connectivity, a concept utilized as an approach to many queries regarding water and/or sediment transport through methodologies which relates a river with its drainage area. In this regard, this study addresses the representation of debris flow in terms of connectivity. We applied a debris flow computational modelling (DFM) and an index of connectivity (IC) in Mascarada catchment, south Brazil, where hundreds of mass movements were triggered in 2017, to evaluate the potential, limitations and capacity of IC to represent patterns of mass movements&amp;#8217; connectivity. The IC is calculated for each cell of the catchment&amp;#8217;s digital elevation model (DEM) (horizontal resolution of 1 m) in relation to the drainage network. Therefore, the IC represents the lateral connectivity (hillslope-channel) and its capacity to mobilize sediment to the channel. The DFM utilizes the Multiple Flow Direction to distribute volumes of a fluid with a determined kinematic viscosity through a slope, originated from initiation areas with a depth pre-determined by the user. The model utilizes uniform and steady flow solutions for Newtonian fluid, considering a rectangular channel. The DFM simulated the observed debris flow reasonably well, with an accuracy of 68%. However, since the simulation reached the channel and carried the volumes beyond the observed debris flow scar, it presented an overestimation area of 65%. When relation the simulated debris flow paths with the IC, we observed a superposition between those paths and high IC values. Also, the results showed a pixel-by-pixel positive linear correlation between high flow depths (representing convergence of flow) and IC, with values varying from 0,1 and 0,5. Only one of the nine simulated debris flow did not reach the channel and it had the lowest mean IC value along its flow path. Simulated debris flow that reached the channel showed high hillslope-channel connectivity, denoting the important role of high magnitude sediment transport events in sediment connectivity. Therefore, the IC was capable to represent and indicate patterns of debris flow that reached the channel. Though, the results also indicated that IC must be carefully interpreted when employed to understand debris flow and related processes &amp;#8211; some areas have high fluid depth due to low connectivity, but others have high depth in response of convergence of flow due to highly connected areas. In this regard, an integration of connectivity and debris flow modelling tools can by an important step to understand sediment connectivity and to represent patterns of high magnitude mass movements events.&lt;/p&gt;

Activation of reverse Na+-Ca2+exchanger by skeletal Na+channel isoform increases excitation-contraction coupling efficiency in rabbit cardiomyocytes

Our prior work has shown that Na+current (INa) affects sarcoplasmic reticular (SR) Ca2+release by activating early reverse of the Na+-Ca2+exchanger (NCX). The resulting Ca2+ entry primes the dyadic cleft, which appears to increase Ca2+channel coupling fidelity. It has been shown that the skeletalisoform of the voltage-gated Na+channel (Nav1.4) is the main tetrodotoxin(TTX)-sensitive Navisoform expressed in adult rabbit ventricular cardiomyocytes.Here I tested the hypothesis that it is also the principal isoform involved in the priming mechanism. Action potentials (AP) were evoked in isolated rabbit ventricular cells loaded with fluo-4, and simultaneouslyrecorded Ca2+transients before and after the application of either relatively low doses of TTX (100nM),the specific Nav1.4 inhibitor μ-Conotoxin GIIIB or the specific Nav1.1 inhibitor ICA 121430. While AP changes after the application of each drug reflected the relative abundance of each isoform, the effects of TTX and GIIIB on SR Ca2+ release (measured as the transient maximum upstroke velocity) were no different. Furthermore, this reduction in SR Ca2+ release wascomparable to the value that we obtained previously when total INawas inactivated with a ramp applied under voltage clamp. Finally, SR Ca2+ release was unaltered by the same ramp in the presence of TTX or GIIB. In contrast, application of ICA had no effect of SR Ca2+release. Theseresults suggest that Nav1.4 is the main Nav isoform involved in regulating the efficiency ofexcitation-contraction coupling in rabbit cardiomyocytes by priming the junction via activation of reverse-mode NCX.