259 research outputs found
MRI in soils: determination of water concent changes due to root water uptake by means of a multi-slice-multi-echo sequence (MSME)
Root water uptake by ricinus communis (castor bean) in fine sand was investigated using MRI with multiecho sampling. Before starting the experiments the plants germinated and grew for 3 weeks in a cylindrical container with a diameter of 9 cm. Immediately before the MRI experiments started, the containers were water-saturated and sealed, so water content changes were only caused by root water uptake. In continuation of a preceding work, where we applied SPRITE we tested a multi-echo multi-slice sequence (MSME). In this approach, the water content was imaged by setting TE = 6.76 ms and nE = 128 with an isotropic resolution of 3.1mm. We calculated the water content maps by biexponential fitting of the multi-slice echo train data and normalisation on reference cuvettes filled with glass beads and 1 mM NiCl2 solution. The water content determination was validated by comparing to mean gravimetric water content measurements. By coregistration with the root architecture, visualised by a 3D fast spin echo sequence (RARE), we conclude that the largest water content changes occurred in the neighbourhood of the roots and in the upper layers of the soil
Combining Neutron and Magnetic Resonance Imaging to Study the Interaction of Plant Roots and Soil
AbstractThe soil in direct vicinity of the roots, the root-soil interface or so called rhizosphere, is heavily modified by the activity of roots, compared to bulk soil, e.g. in respect to microbiology and soil chemistry. It has turned out that the root-soil interface, though small in size, also plays a decisive role in the hydraulics controlling the water flow from bulk soil into the roots. A promising approach for the non-invasive investigation of water dynamics, water flow and solute transport is the combination of the two imaging techniques magnetic resonance imaging (MRI) and neutron imaging (NI). Both methods are complementary, because NI maps the total proton density, possibly amplified by NI tracers, which usually corresponds to total water content, and is able to detect changes and spatial patterns with high resolution. On the other side, nuclear magnetic resonance relaxation times reflect the interaction between fluid and matrix, while also a mapping of proton spin density and thus water content is possible. Therefore MRI is able to classify different water pools via their relaxation times additionally to the water distribution inside soil as a porous medium. We have started such combined measurements with the approach to use the same samples and perform tomography with each imaging method at different location and short-term sample transfer
Potential short-term earthquake forecasting by farm animal monitoring
Whether changes in animal behavior allow for short-term earthquake predictions has been debated for a long time. Before, during and after the 2016/2017 earthquake sequence in Italy, we deployed bio-logging tags to continuously observe the activity of farm animals (cows, dogs, and sheep) close to the epicenter of the devastating magnitude M6.6 Norcia earthquake (Oct–Nov 2016) and over a subsequent longer observation period (Jan–Apr 2017). Relating 5,304 (in 2016) and 12,948 (in 2017) earthquakes with a wide magnitude range (0.4 ≤ M ≤ 6.6) to continuously measured animal activity, we detected how the animals collectively reacted to earthquakes. We also found consistent anticipatory activity prior to earthquakes during times when the animals were in a building (stable), but not during their time on a pasture. We detected these anticipatory patterns not only in periods with high, but also in periods of low seismic activity. Earthquake anticipation times (1–20 hr) are negatively correlated with the distance between the farm and earthquake hypocenters. Our study suggests that continuous bio-logging of animal collectives has the potential to provide statistically reliable patterns of pre-seismic activity that could yield valuable insights for short-term earthquake forecasting. Based on a priori model parameters, we provide empirical threshold values for pre-seismic animal activities to be used in real-time observation stations
Gene expression profiling of bovine ovarian follicular and luteal cells provides insight into cellular identities and functions
After ovulation, somatic cells of the ovarian follicle (theca and granulosa cells) become the small and large luteal cells of the corpus luteum. Aside from known cell type-specific receptors and steroidogenic enzymes, little is known about the differences in the gene expression profiles of these four cell types. Analysis of the RNA present in each bovine cell type using Affymetrix microarrays yielded new cell-specific genetic markers, functional insight into the behavior of each cell type via Gene Ontology Annotations and Ingenuity Pathway Analysis, and evidence of small and large luteal cell lineages using Principle Component Analysis. Enriched expression of select genes for each cell type was validated by qPCR. This expression analysis offers insight into cell-specific behaviors and the differentiation process that transforms somatic follicular cells into luteal cells
Response to Zöller et al.'s critique on “Potential short-term earthquake forecasting by farm-animal monitoring”
Zöller et al. (Ethology, 2020) criticize our original publication (Wikelski et al., Ethology, 126(9), 2020, 931) for obvious reasons: we only observed the behavior of one group of farm animals before, during and after one earthquake series in one area of the world. It is clear that no earthquake predictions are possible, and should not be attempted, from this data set. However, what we show is that there is important information within this animal collective pertaining to potential future local forecasting of earthquakes when combined with traditional data sources. We maintain that combining Zöller et al.'s (2020) modeling tools with the adequate use of our data can stimulate novel ways of earthquake forecasting. Future studies should combine both approaches
Reproductive Aging Influences Ovarian Function in Beef Cows
Anti-MĂĽllerian Hormone (AMH) has been associated with follicle number and age of the ovary. Therefore, our hypothesiswas that AMH was a biomarker for both follicle number and ovarian function in the beef cow. Ovaries were collected by flank laparotomy. The number of follicles increased as cows aged from 1.5 to 6 years and began to decrease thereafter; however, the size of the ovary continued to increase with advanced age. Expression of the AMH gene increased with increasing follicle number in 2-year-old beef cows. These results suggest that heifers with larger ovaries will have greater numbers of follicles and greater productivity, allowing them to stay in the production herd longer. AMH could be used to identify heifers of high reproductive potential at a very young age
Beidseitige Informationsasymmetrien in der Arzt-Patient-Beziehung: Implikationen fĂĽr die GKV
Die vorliegende Arbeit analysiert die Interdependenzen und Informationsstrukturen im Gesundheitswesen. Hauptansatzpunkt ist die beidseitig asymmetrische Information zwischen Arzt und Patient. Der Patient kann i. d. R. weder die Wirkung der Leistungen des Arztes genau einordnen, noch besitzt der Arzt genauere Informationen über das behandlungsbegleitende Verhalten des Patienten. Die Interdependenzen zwischen diesen Handlungen bestimmen das resultierende Gleichgewicht. Die Einführung einer Selbstbeteiligung für den Patienten führt zu einer verbesserten Compliance, das Niveau der medizinischen Leistung hängt von den Interdependenzen ab. Die Implikationen, die sich aus dem Modell ergeben, lassen auf ein Kommunikationsdefizit zwischen Arzt und Patient schließen. Eine Stärkung der Compliance ist zum einen durch verbesserte Information des Arztes, zum anderen durch finanzielle Anreize, insbesondere durch die Einführung einer Selbstbeteiligung, möglich. Die Krankenkassen als ergänzender Sachwalter der Patienten können in der Arzt-Patient-Beziehung vor allem Aufgaben wie Vertragsabschlüsse übernehmen, benötigen dazu jedoch mehr Gestaltungsfreiheit
Nomenclature for renal replacement therapy and blood purification techniques in critically ill patients: practical applications
This article reports the conclusions of the second part of a consensus expert conference on the nomenclature of renal replacement therapy (RRT) techniques currently utilized to manage acute kidney injury and other organ dysfunction syndromes in critically ill patients. A multidisciplinary approach was taken to achieve harmonization of definitions, components, techniques, and operations of the extracorporeal therapies. The article describes the RRT techniques in detail with the relevant technology, procedures, and phases of treatment and key aspects of volume management/fluid balance in critically ill patients. In addition, the article describes recent developments in other extracorporeal therapies, including therapeutic plasma exchange, multiple organ support therapy, liver support, lung support, and blood purification in sepsis. This is a consensus report on nomenclature harmonization in extracorporeal blood purification therapies, such as hemofiltration, plasma exchange, multiple organ support therapies, and blood purification in sepsis
Out-of-pocket expenditures for pharmaceuticals: lessons from the Austrian household budget survey
BACKGROUND: Paying pharmaceuticals out-of-pocket is an important source of financing pharmaceutical consumption. Only limited empirical knowledge is available on the determinants of these expenditures. OBJECTIVES: In this paper we analyze which characteristics of private households influence out-of-pocket pharmaceutical expenditure (OOPPE) in Austria. DESIGN & METHODS: We use cross-sectional information on OOPPE and on household characteristics provided by the Austrian household budget survey 2009/10. We split pharmaceutical expenditures into the two components prescription fees and over-the-counter (OTC) expenditures. To adjust for the specific characteristics of the data we compare different econometric approaches: two-part model, hurdle model, generalized linear model, zero-inflated negative binomial regression model. FINDINGS: The finally selected econometric approaches give a quite consistent picture. The probability of expenditures of both types is strongly influenced by the household structure. It increases with age, doctoral visits and the presence of a female householder. The education level and income only increase the probability of OTC-pharmaceuticals. The level of OTC-expenditures remains widely unexplained while the household structure and age influences the expenditures for prescription fees. Insurance characteristics of private households either private or public play a minor role in explaining the expenditure levels in all specifications. This refers to a homogenous and comprehensive provision of pharmaceuticals in the public part of the Austrian health care system. CONCLUSIONS: The paper gives useful insights into the determinants of pharmaceutical expenditures of private households and supplements the previous research which focuses on the individual level
Need-based resource allocation: different need indicators, different results?
<p>Abstract</p> <p>Background</p> <p>A key policy objective in most publicly financed health care systems is to allocate resources according to need. Many jurisdictions implement this policy objective through need-based allocation models. To date, no gold standard exists for selecting need indicators. In the absence of a gold standard, sensitivity of the choice of need indicators is of concern. The primary objective of this study was to assess the consistency and plausibility of estimates of per capita relative need for health services across Canadian provinces based on different need indicators.</p> <p>Methods</p> <p>Using the 2000/2001 Canadian Community Health Survey, we estimated relative per capita need for general practitioner, specialist, and hospital services by province using two approaches that incorporated a different set of need indicators: (1) demographics (age and sex), and (2) demographics, socioeconomic status, and health status. For both approaches, we first fitted regression models to estimate standard utilization of each of three types of health services by indicators of need. We defined the standard as average levels of utilization by needs indicators in the national sample. Subsequently, we estimated expected per capita utilization of each type of health services in each province. We compared these estimates of per capita relative need with premature mortality in each province to check their face validity.</p> <p>Results</p> <p>Both approaches suggested that expected relative per capita need for three services vary across provinces. Different approaches, however, yielded different and inconsistent results. Moreover, provincial per capita relative need for the three health services did not always indicate the same direction of need suggested by premature mortality in each province. In particular, the two approaches suggested Newfoundland had less need than the Canadian average for all three services, but it had the highest premature mortality in Canada.</p> <p>Conclusion</p> <p>Substantial differences in need for health care may exist across Canadian provinces, but the direction and magnitude of differences depend on the need indicators used. Allocations from models using survey data lacked face validity for some provinces. These results call for the need to better understand the biases that may result from the use of survey data for resource allocation.</p
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