Modelling the impacts of land cover change on flood hydrographs in upland peat catchments

There is global concern about headwater management and associated impacts on river flow. In many wet temperate zones peatlands can be found in headwater catchments. In the UK there is major concern about how environmental change, driven by human interventions, has altered the surface cover of headwater blanket peatlands. However, the impact of such cover changes on river flow is poorly understood. In particular, there is poor understanding of the impacts of different spatial configurations of bare peat or well-vegetated restored peat on river flow peaks in upland catchments. This thesis employs a numerical modelling approach to explore such impacts. TOPMODEL, due to its process representation which is very suitable for blanket peat catchments, was utilized as a prototype acting as the basis for a new distributed catchment hydrological model. A new overland flow module with a set of detailed stochastic algorithms representing overland flow routing and re-infiltration mechanisms was created to simulate saturation-excess overland flow movement. The influence of land cover on surface roughness could be represented in the model. The new model was tested in three upland peat catchments in different parts of the UK: Trout Beck in the North Pennines, the Wye in mid-Wales and the East Dart in southwest England. The model was found to work well in all three cases. Land cover scenarios were designed for the three catchments to investigate land cover impact on river flow through simulation runs of the new version of TOPMODEL. As a result of hypothesis testing three land cover principles emerged from the work as follows: Principle (1): A wider bare peat strip nearer to the river channel gives a higher flow peak and reduces the delay to peak; conversely, a wider buffer strip with higher density vegetation (e.g. Sphagnum) leads to a lower peak and postpones the peak. In both cases, a narrower buffer strip surrounding upstream and downstream channels has a greater effect than a thicker buffer strip just based around the downstream river network. Principle (2): When the area of change is equal, the size of land cover change patches has no effect on river flow for patch sizes up to 10000m2. Principle (3): Bare peat on gentle slopes gives a faster flow response and higher peak value at the catchment outlet, while high density vegetation or re-vegetation on a gentle slope area has larger positive impact on peak river flow delay when compared with the same practices on steeper slopes. These simple principles should be useful to planners who wish to determine resource efficiency and optimisation for peatland protection and restoration works in headwater systems. If practitioners require further detail on impacts of specific spatial changes to land cover in a catchment then the new model can be readily applied to new catchments of concern. The model also has the potential to provide useful information on potential sediment or contaminant transfers because it has a fully distributed overland flow modul

The change of intimate relationship between people with Alzheimer's disease and their adult child caregivers : An interpretative phenomenological analysis

This study aims to explore the change of intimate relationship between people with Alzheimer’s disease and their adult child caregivers as the disease progresses. Twelve adult child caregivers were recruited through purposive sampling. Explanatory phenomenological analysis was conducted to analyse data collected by semi-structured in-depth interviews. This study found a dynamically changing relationship between adult child caregivers and their parents with Alzheimer’s disease during care giving that evolved with the progress of the disease. The relationship was the most intimate in the middle stage of the disease for most caregivers and a new reciprocal relationship developed due to caregiving. Caregivers experienced different degrees of self-growth when providing care, though caregiver burdens were common. The positive experience and perception of caregivers were important for improving the quality of life for adult child caregivers of people with Alzheimer’s disease

Influencing factors of psychological well-being of the non-designated hospital staff in China during the COVID-19 pandemic

Background: Recent studies report that hospital staff at the forefront of caring for COVID-19 patients experience increased psychological distress. To effectively manage the outbreak of COVID-19, China established COVID-19 designated and non-designated hospitals. To date, few studies have examined the impacts of COVID-19 on psychological health of staff working at non-designated hospitals. This study is to explore factors affecting psychological health of non-designated hospital staff in China during the COVID-19 pandemic. Methods: Data were collected through an online questionnaire between February and March 2020. The questionnaire consists of General Health Questionnaire (GHQ-20), Social Support Rating Scale (SSRS), Simplified Coping Style Questionnaire (SCSQ), sociodemographic characteristics, employment history, health status, and contact history of COVID-19. The questionnaire was distributed through hospital WeChat groups and work colleague referrals. A total of 470 non-designated hospital staff members completed the questionnaire. Multiple Linear Regression analysis was used to interpret the associations among social support, coping styles, sociodemographic factors, job roles, and psychological status. Data were analyzed using SPSS version 21.0.Results: The non-designated hospital staff differed significantly in anxiety and depression subscores of the GHQ-20 by their job roles, levels of social support, and history of mental disorders. Staff with medical job roles, good self-reported health status, no previous mental disorders, adequate social support, and positive coping styles scored lower in GHQ-20 total score, which indicated healthier psychological status. Conclusions: The results indicate that history of mental health disorders, non-medical job roles, and inadequate social support are associated with greater psychological distress. Personalized support should be provided to those who are vulnerable and in need of social and psychological support

The effect of Shengmai injection in patients with coronary heart disease in real world and its personalized medicine research using machine learning techniques

Objective: Shengmai injection is a common treatment for coronary heart disease. The accurate dose regimen is important to maximize effectiveness and minimize adverse reactions. We aim to explore the effect of Shengmai injection in patients with coronary heart disease based on real-world data and establish a personalized medicine model using machine learning and deep learning techniques.Methods: 211 patients were enrolled. The length of hospital stay was used to explore the effect of Shengmai injection in a case-control study. We applied propensity score matching to reduce bias and Wilcoxon rank sum test to compare results between the experimental group and the control group. Important variables influencing the dose regimen of Shengmai injection were screened by XGBoost. A personalized medicine model of Shengmai injection was established by XGBoost selected from nine algorithm models. SHapley Additive exPlanations and confusion matrix were used to interpret the results clinically.Results: Patients using Shengmai injection had shorter length of hospital stay than those not using Shengmai injection (median 10.00 days vs. 11.00 days, p = 0.006). The personalized medicine model established via XGBoost shows accuracy = 0.81 and AUC = 0.87 in test cohort and accuracy = 0.84 and AUC = 0.84 in external verification. The important variables influencing the dose regimen of Shengmai injection include lipid-lowering drugs, platelet-lowering drugs, levels of GGT, hemoglobin, prealbumin, and cholesterol at admission. Finally, the personalized model shows precision = 75%, recall rate = 83% and F1-score = 79% for predicting 40 mg of Shengmai injection; and precision = 86%, recall rate = 79% and F1-score = 83% for predicting 60 mg of Shengmai injection.Conclusion: This study provides evidence supporting the clinical effectiveness of Shengmai injection, and established its personalized medicine model, which may help clinicians make better decisions

The impact of land-cover change on flood peaks in peatland basins

In headwater peatlands, saturation-excess overland flow is a dominant source of river discharge. Human modifications to headwater peatlands result in vegetation cover change but there is a lack of understanding about how the spatial distribution of such change impacts flood peaks. A fully distributed version of TOPMODEL with an overland flow velocity module was used to simulate flood response for three upland peat basins. Bare peat strips adjacent to channels resulted in a higher and faster flow peak; for a 20 mm/hr rainfall event, with bare riparian zones covering 10% of the basin area, peaks were increased, compared to the current hydrograph, by 12.8%, 1.8% and 19.6% in the three basins. High density Sphagnum ground cover over the same riparian zones reduced flow peaks (e.g. by 10.1%, 1.8% and 13.4% for the 20 mm hr-1 event) compared to the current hydrograph. With similar total areas of land-cover change, the size of randomly located patches of changed cover had no effect on peak flow for patch sizes up to 40000 m2. However, cover changes on gentle slope areas generally resulted in a larger change in peak flow when compared with the same changes on steeper slopes. Considering all results for the same proportion of catchment area that undergoes change, land-cover change along narrow riparian buffer strips had the highest impact on river flow. Thus, the protection and revegetation of damaged riparian areas in upland peat catchments may be highly beneficial for flood management

The wPDI Redox Cycle Coupled Conformational Change of the Repetitive Domain of the HMW-GS 1Dx5—A Computational Study

The repetitive sequence of glutenin plays an important role in dough rheology; however, its interaction with wheat protein disulfide isomerase (wPDI) remains unclear. In this study, the conformations of wild type glutenin repetitive sequence (WRS) from the high molecular weight glutenin subunit (HMW-GS) 1Dx5, an artificially designed glutenin repetitive sequence (DRS) of which the amino acid composition is the same but the primary structure is different, and wPDI under different redox states were simulated. The molecular interactions between the aforementioned repetitive sequences with wPDI under different redox states were further investigated. The results indicated that the repetitive sequences bind to the b and b′ domains of an “open”, oxidized wPDI (wPDIO) which serves as the acceptor state of substrate. The repetitive sequence is partially folded (compressed) in wPDIO, and is further folded in the thermodynamically favored, subsequent conformational transition of wPDIO to reduced wPDI (wPDIR). Compared with the artificially designed one, the naturally designed repetitive sequence is better recognized and more intensively folded by wPDI for its later unfold as the molecular basis of dough extension

Molecular Mechanism of Cyanidin-3-<i>O</i>-Glucoside Disassembling Aβ Fibril In Silico

The deposition of β-amyloid (Aβ) in the brain leads to neurotoxic effects and subsequent Alzheimer’s disease (AD). While AD is becoming more and more prevalent in modern society, therapeutic efforts targeting Aβ could be a promising solution. Currently, two natural products are reported to disintegrate preformed Aβ fibril in vitro. Meanwhile, the chemical driving force behind this phenomenon remains unknown. Taking cyanidin-3-O-glucoside (Cy-3G) as an example, here we studied its interaction with different Aβ polymorphs in silico. Negative charges on different Aβ polymorphs draw the interaction with the flavylium cation on Cy-3G. Our results show that Aβ in a single peptide form in solution exposed more hydrophobic solvent accessible surface area than its fibril structure (per protomer), and Cy-3G interacts more intensively with the single peptide form than fibril as indicated by more hydrogen bonding formed and more amino acid residues involved in their hydrophobic interactions. Thus, the single Aβ peptide aggregation into fibril and fibril dissociation into single peptide equilibrium could be disturbed by the preferential binding of Cy-3G to the monomeric Aβ peptide, which leads to the disassembly of the pathogenic Aβ fibril. This study offers a novel perspective of Cy-3G alleviated AD syndrome beyond its dogmatic antioxidant activity

Modelling Effects of Rainfall Patterns on Runoff Generation and Soil Erosion Processes on Slopes

Rainfall patterns and landform characteristics are controlling factors in runoff and soil erosion processes. At a hillslope scale, there is still a lack of understanding of how rainfall temporal patterns affect these processes, especially on slopes with a wide range of gradients and length scales. Using a physically-based distributed hydrological model (InHM), these processes under different rainfall temporal patterns were simulated to illustrate this issue. Five rainfall patterns (constant, increasing, decreasing, rising-falling and falling-rising) were applied to slopes, whose gradients range from 5&deg; to 40&deg; and projective slope lengths range from 25 m to 200 m. The rising-falling rainfall generally had the largest total runoff and soil erosion amount; while the constant rainfall had the lowest ones when the projective slope length was less than 100 m. The critical slope of total runoff was 15&deg;, which was independent of rainfall pattern and slope length. However, the critical slope of soil erosion amount decreased from 35&deg; to 25&deg; with increasing projective slope length. The increasing rainfall had the highest peak discharge and erosion rate just at the end of the peak rainfall intensity. The peak value discharges and erosion rates of decreasing and rising-falling rainfalls were several minutes later than the peak rainfall intensity