Wear due to sediment particles in fluid flows, also termed ‘hydroabrasion’ or simply ‘abrasion’, is an omnipresent issue at hydraulic structures as well as in bedrock rivers. However, interactions ...between flow field, particle motion, channel topography, material properties and abrasion have rarely been investigated on a prototype scale, leaving many open questions as to their quantitative interrelations. Therefore, we investigated hydroabrasion in a multi-year field study at two Swiss Sediment Bypass Tunnels (SBTs). Abrasion depths of various invert materials, hydraulics and sediment transport conditions were determined and used to compute the abrasion coefficients kv of different abrasion models for high-strength concrete and granite. The results reveal that these models are useful to estimate spatially averaged abrasion rates. The kv‑value is about one order of magnitude higher for granite than for high-strength concrete, hence, using material-specific abrasion coefficients enhances the prediction accuracy. Three-dimensional flow structures, i.e., secondary currents occurring both, in the straight and curved sections of the tunnels cause incision channels, while also longitudinally undulating abrasion patterns were observed. Furthermore, hydroabrasion concentrated along joints and protruding edges. The maximum abrasion depths were roughly twice the mean abrasion depths, irrespective of hydraulics, sediment transport conditions and invert material.
Sediment transport in glacier basins and rivers, and hence reservoir sedimentation tend to increase under the impact of climate change. The raise of bedload transport rates results in an increase of ...hydro-abrasive erosion leading to bedrock incision in rivers and wear at hydraulic structures. Mechanistic abrasion models are a helpful tool for both river and landscape evolution and hydroabrasion of hydraulic structures. Therefore, knowledge of the physical processes of turbulent flow characteristics, bedload particle motion, and hydroabrasion and their interrelations is needed. Ongoing research at VAW of ETH Zurich aims at improving the required knowledge to address hydroabrasion issues by means of laboratory and prototype experiments in supercritical flows over fixed smooth and transitionally rough beds. A physical model investigation revealed that particle trajectories on fixed planar beds are rather symmetric, flat and long compared to alluvial beds. By applying newly developed particle motion equations, an existing mechanistic abrasion model was adapted and calibrated for concrete and natural rock by means of prototype data. This advances abrasion prediction modelling and contributes to a better understanding of river bed and landscape evolution and to a sustainable design and operation of hydraulic structures facing severe hydro-abrasive erosion.
Nation-wide hospitalization databases include diagnostic information at the level of an entire population over an extended period of time. Comorbidity network and early disease development can be ...unveiled. Chronic obstructive pulmonary disease (COPD) is an underdiagnosed condition for which it is crucial to identify early disease indicators. The identification of gender-specific conditions preceding the onset of COPD may reveal disease progression patterns allowing for early diagnosis and intervention. The objective of the study was to investigate the antecedent hospitalization history of patients newly diagnosed with COPD and to retrace a gender-specific trajectory of coded entities prior to the onset of COPD.
A population-wide hospitalization database including information about all hospitalizations in Switzerland between 2002 and 2018 was used. COPD cases were extracted from the database and comorbidities occurring prior to the onset of COPD identified. Comorbidities significantly over-represented in COPD compared with a 1:1, age- and sex-matched control population were identified and their longitudinal evolution was analyzed.
Between 2002 and 2018, 697,714 hospitalizations with coded COPD were recorded in Switzerland. Sixty-two diagnoses were significantly over-represented before onset of COPD. These preceding comorbidities included both well-established conditions and novel links to COPD. Early pre-conditions included nicotine and alcohol abuse, obesity and cardiovascular diseases. Later comorbidities included atrial fibrillation, diseases of the genitourinary system and pneumonia. Atherosclerotic heart diseases were more prevalent in males, whereas hypothyroidism, varicose and intestinal disorders were more frequent in females. Disease trajectories were validated using an independent data set.
Gender-specific disease trajectories highlight early indicators and pathogenetic links between COPD and antecedent diseases and could allow for early detection and intervention.
GPR40 (FFA1) is a fatty acid receptor whose activation results in potent glucose lowering and insulinotropic effects in vivo. Several reports illustrate that GPR40 agonists exert glucose lowering in ...diabetic humans. To assess the mechanisms by which GPR40 partial agonists improve glucose homeostasis, we evaluated the effects of MK-2305, a potent and selective partial GPR40 agonist, in diabetic Goto Kakizaki rats. MK-2305 decreased fasting glucose after acute and chronic treatment. MK-2305-mediated changes in glucose were coupled with increases in plasma insulin during hyperglycemia and glucose challenges but not during fasting, when glucose was normalized. To determine the mechanism(s) mediating these changes in glucose metabolism, we measured the absolute contribution of precursors to glucose production in the presence or absence of MK-2305. MK-2305 treatment resulted in decreased endogenous glucose production (EGP) driven primarily through changes in gluconeogenesis from substrates entering at the TCA cycle. The decrease in EGP was not likely due to a direct effect on the liver, as isolated perfused liver studies showed no effect of MK-2305 ex vivo and GPR40 is not expressed in the liver. Taken together, our results suggest MK-2305 treatment increases glucose stimulated insulin secretion (GSIS), resulting in changes to hepatic substrate handling that improve glucose homeostasis in the diabetic state. Importantly, these data extend our understanding of the underlying mechanisms by which GPR40 partial agonists reduce hyperglycemia.
The Geography of Warscape Korf, Benedikt; Engeler, Michelle; Hagmann, Tobias
Third world quarterly,
04/2010, Letnik:
31, Številka:
3
Journal Article
Recenzirano
Odprti dostop
This article elaborates a heuristic approach to understanding the geography of warscape from a theoretically informed perspective. It argues that agency in protracted civil war emerges at the ...ambiguous interface of different, competing systems of power and authority. In order to account for the multiple trajectories of threat and opportunity that warscapes offer to different social actors and at different times and places, the article proposes the concept of 'governable order', which is derived from a critical review of the literature on 'social navigation' and 'governable space(s)'. The usefulness of combining these three concepts is illustrated by two empirical vignettes. They demonstrate the dynamics of governable spaces in distinct phases of the Sierra Leone and Sri Lanka civil wars. The two cases highlight the temporal and territorial fluidity of governable spaces, which both constrain and enable warscape inhabitants' agency.
Psychiatric emergencies have increased in recent decades, particularly with the onset of the SARS-CoV-2 pandemic, and far too little is known about the backgrounds of these emergencies. In this ...study, we investigated the extent to which the number of psychiatric emergencies changed during and in the aftermath of the SARS-CoV-2 pandemic at the Child and Adolescent Psychiatry (CAP) Tübingen. We considered age and psychiatric diagnoses. Additionally, we evaluated the backgrounds of the emergencies. We applied a mixed- (quantitative and qualitative) methods approach to data on emergency presentations at the CAP Tübingen from the pre-SARS-CoV-2 pandemic period (October 2019-January 2020) to Restriction Phase 1 (October 2020-January 2021), Restriction Phase 2 (October 2021-January 2022), and endemic phase (October 2022-January 2023). The total number of emergencies and those with eating disorders and affective disorders increased, while obsessive-compulsive disorders, expansive disorders and anxiety disorders decreased. The patients presenting in the pre-SARS-CoV-2 pandemic period were younger than those in the subsequent periods. We content-coded the reasons behind the emergency presentations. We also identified four areas of stressors and personality characteristics associated with the emergency presentations. In light of the increasing number of psychiatric emergencies, the long-term aim should be to meet the growing demands and create options for prevention.
To review effective approaches for non-pain symptom management for cancer patients focusing on treatment of nausea and vomiting, constipation, diarrhea, anorexia/cachexia, fatigue, and dyspnea.
...Peer-reviewed articles, clinical practice guidelines, professional organization position statements.
Oncology nurses are key advocates for optimal symptom management. Maximizing palliation of symptoms improves quality of life and prolongs survival.
To provide an evidence-based approach to symptom management, oncology nurses require a deep understanding of symptom pathophysiology while anticipating side effects, educating patients and caregivers, considering psychosocial/spiritual factors, exploring treatment expectations, and clarifying goals of treatment.
Advance care planning (ACP) is a clinical skill that can be taught. An opportunity exists to teach how to conduct ACP to clinicians not typically engaged in these conversations to increase the ...likelihood that patients and caregivers engage in ACP. We conducted a prospective study exploring the feasibility of a pharmacist-led ACP intervention.
We completed a prospective, single-center study from July 2015 to July 2017. We included patients of age ≥ 18 years with incurable cancer referred to the palliative care clinic. A trained pharmacist led an ACP discussion with the patient and selected proxy. We defined feasibility as completion of ≥ 30 pharmacist-led ACP discussions over the study period. Additionally, we defined an informed healthcare proxy as someone who understood three key end-of-life (EOL) treatment preferences: the patient's personal definition of quality of life, desired resuscitation status, and preferred location of death (in or out of the hospital). Patients were followed until the end of the study or death. For those patients who died, the pharmacist contacted the proxy for follow-up and explored satisfaction with the ACP intervention.
Thirty-four patients completed the study. All selected proxies completed the intervention and were able to understand the three EOL preferences. At the time of the patient's death (n = 20), proxies reported that 66.6% received their preferred resuscitation status and 72.2% died in their preferred location. Proxy satisfaction with the ACP process was 7.6 ± 2.5 (mean ± SD) on a 11-point Likert scale.
These findings indicate the potential for pharmacists to lead and engage in ACP in the outpatient setting.
Remarkably large rotational diffusion rates have been determined for silica-attached 1-pyrene at the solid/air interface through time-dependent fluorescence anisotropy measurements. Diffusion rates D ...∥ and D ⊥ were determined to be 4 × 106 and 2 × 106 s-1, respectively, by treating the motion of the attached moiety as an oblate ellipsoid of rotation. 13C NMR measurements on solid, silica-attached benzene-1-13 C, acquired using conventional solution NMR methods, gave remarkable, high-resolution spectra. A lower limit for the rate of phenyl group motion was estimated to be 1.5 × 105 s-1, consistent with the fluorescence anisotropy data measured for silica-attached 1-pyrene. Molecular mechanics models for phenyl attached to representative silanol surfaces predict rotational barriers for phenyl rotations in the 2−5 kcal/mol range.
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