Blue-fluorescence of NADPH as an indicator of marine primary production

Nicotinamide Adenine Dinucleotide Phosphate (NADPH) is the primary product of photosynthesisand can therefore serve as an indicator of biomass and photosynthetic activity. Pure NADPH whichis the reduced form of NADP shows an absorption maximum at 340 nm and a maximum of emissionat 460 nm. NADPH concentrations in terrestrial vegetation have already been studied since1957 in great detail with optical methods. However, its potential as a biomass parameter of oceanicphytoplankton which can be assessed in situ and remotely with fluorescence spectroscopy has notyet been investigated.In this paper, we report on laboratory investigations of the blue-fluorescence spectrum in algalsuspensions of Chlorella and Thalassiosira when excited with UV-A light. It is shown that cell densitiesof about 106 per litre as they are typically found under natural conditions are too low for precisedetection of NADPH fluorescence, while concentrated samples with 108-1010 cells per litre exhibitsignificant blue-fluorescence which can be related to NADPH. Inhibition of photosynthetic activityby addition of DCMU decreases the strength of blue-fluorescence remarkably. Since NADPHis an end product of photosynthesis, changes of PAR illumination levels should directly affect itsconcentration and hence the intensity of blue-fluorescence. However, no effect of illumination onblue-fluorescence could be observed in our study. Possible reasons of these observations are discussed,and perspectives for practical applications of the method used are proposed

Process-response systems in physical geography

Physisch-geographische Studien erfordern zur Lösung der gestellten Forschungsaufgaben nicht immer bis ins letzte Detail gehende Untersuchungen oder umfassende Datensammlungen im Gelände. Bei der Analyse kausaler zusammenhänge landschaftswirksamer Prozesse sollte man einer Gruppe von grundlegenden Prinzipien Aufmerksamkeit schenken, die auf die meisten Forschungsprobleme in der "physikalischen" Geographie anwendbar sind. Nach Meinung des Autors muß Forschung und Lehre in der physischen Geographie unter Beachtung der physikalischen Gesetzmäßigkeiten wesentlich verbreitert werden, damit Process-Response-Modelle in sie einbezogen werden können. Eine verstärkte deterministische Richtung erhält viele ihrer Grundlagen durch die Anwendung des Ersten Gesetzes der Thermodynamik und Newtons Zweitem Gesetz. Numerische Modelle physischer Process-Response-Systeme zielen letzten Endes auf eine Einbeziehung sozialwirtschaftlicher Entscheidungssysteme hin. Dadurch erhält die physische Geographie eine größere Relevanz für die kulturwirtschaftlichen Richtungen unserer Disziplin und für die menschlichen Belange schlechthin

An analysis of crowdfunding as a viable form of financial for start-ups in Portugal

Crowdfunding evolved as part of the world’s progress towards a global and digital society. Over the past years, leveraging the ‘power of the crowd’ has become an increasingly popular way to obtain financing. This research is an effort to analyse the extend to which Crowdfunding is used as a form and source of financing for start-ups in Portugal. As such, this dissertation is an empirical work encompassing an extensive literature review on the concept of Crowdfunding, its origin, development and current state and offers an analysis for the case of Portugal. Through elite interviews with operators of existing platforms in Portugal, Portuguese start-ups and finance experts familiar with the market, the research question receives a thorough examination concluding that Crowdfunding has the potential to become a viable form of financing for start-ups in Portugal

Cost-effectiveness of non-invasive methods for assessment and monitoring of liver fibrosis and cirrhosis in patients with chronic liver disease: systematic review and economic evaluation

BACKGROUND: Liver biopsy is the reference standard for diagnosing the extent of fibrosis in chronic liver disease; however, it is invasive, with the potential for serious complications. Alternatives to biopsy include non-invasive liver tests (NILTs); however, the cost-effectiveness of these needs to be established. OBJECTIVE: To assess the diagnostic accuracy and cost-effectiveness of NILTs in patients with chronic liver disease. DATA SOURCES: We searched various databases from 1998 to April 2012, recent conference proceedings and reference lists. METHODS: We included studies that assessed the diagnostic accuracy of NILTs using liver biopsy as the reference standard. Diagnostic studies were assessed using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2) tool. Meta-analysis was conducted using the bivariate random-effects model with correlation between sensitivity and specificity (whenever possible). Decision models were used to evaluate the cost-effectiveness of the NILTs. Expected costs were estimated using a NHS perspective and health outcomes were measured as quality-adjusted life-years (QALYs). Markov models were developed to estimate long-term costs and QALYs following testing, and antiviral treatment where indicated, for chronic hepatitis B (HBV) and chronic hepatitis C (HCV). NILTs were compared with each other, sequential testing strategies, biopsy and strategies including no testing. For alcoholic liver disease (ALD), we assessed the cost-effectiveness of NILTs in the context of potentially increasing abstinence from alcohol. Owing to a lack of data and treatments specifically for fibrosis in patients with non-alcoholic fatty liver disease (NAFLD), the analysis was limited to an incremental cost per correct diagnosis. An analysis of NILTs to identify patients with cirrhosis for increased monitoring was also conducted. RESULTS: Given a cost-effectiveness threshold of £20,000 per QALY, treating everyone with HCV without prior testing was cost-effective with an incremental cost-effectiveness ratio (ICER) of £9204. This was robust in most sensitivity analyses but sensitive to the extent of treatment benefit for patients with mild fibrosis. For HBV [hepatitis B e antigen (HBeAg)-negative)] this strategy had an ICER of £28,137, which was cost-effective only if the upper bound of the standard UK cost-effectiveness threshold range (£30,000) is acceptable. For HBeAg-positive disease, two NILTs applied sequentially (hyaluronic acid and magnetic resonance elastography) were cost-effective at a £20,000 threshold (ICER: £19,612); however, the results were highly uncertain, with several test strategies having similar expected outcomes and costs. For patients with ALD, liver biopsy was the cost-effective strategy, with an ICER of £822. LIMITATIONS: A substantial number of tests had only one study from which diagnostic accuracy was derived; therefore, there is a high risk of bias. Most NILTs did not have validated cut-offs for diagnosis of specific fibrosis stages. The findings of the ALD model were dependent on assuptions about abstinence rates assumptions and the modelling approach for NAFLD was hindered by the lack of evidence on clinically effective treatments. CONCLUSIONS: Treating everyone without NILTs is cost-effective for patients with HCV, but only for HBeAg-negative if the higher cost-effectiveness threshold is appropriate. For HBeAg-positive, two NILTs applied sequentially were cost-effective but highly uncertain. Further evidence for treatment effectiveness is required for ALD and NAFLD. STUDY REGISTRATION: This study is registered as PROSPERO CRD42011001561. FUNDING: The National Institute for Health Research Health Technology Assessment programme

Artübergreifende Bestimmung von Parametern des Primärwurzelwachstums durch raum-zeitlich hochaufgelöste Bildsequenzanalyse unter besonderer Berücksichtigung der Variation der externen Nährstoffverfügbarkeit

Im Rahmen dieser Arbeit wurde das Primärwurzelwachstum vier verschiedener Arten (Arabidopsis, Nicotiana, Solanum und Zea) genau analysiert. Dabei konnte eine sehr hohe räumliche und zeitliche Auflösung erzielt werden, die bisher in dieser Kombination nicht erreicht wurde. Dies wurde durch die Anwendung einer innovativen Bildsequenzanalyse (DISP-Methode) möglich. Um die genannte Methode auf sehr kleinen Wurzeln (Durchmesser < 0,3 mm) anwenden zu können, wurde ein ‚Mikrorhizotron’-Aufbau konstruiert, mit dem die notwendige raum-zeitliche Auflösung erreicht wurde. In interdisziplinärer Zusammenarbeit wurde die Verfolgung der Wurzelspitze im Bildbereich zur kontinuierlichen Wurzelbeobachtung über mehrere Tage entwickelt und Optimierungen im Bereich des Auswertungsverfahrens eingeführt. Durch die Anwendung der weiterentwickelten DISP-Methode konnte eine Vielzahl neuer Erkenntnisse gewonnen werden. Invarianten des Wachstums: Die vergleichende Analyse der Wachstumsmuster hat ergeben, dass das Maximum der relativen elementaren Wuchsrate ( REGRmax), der Abstand der REGRmax von der Wurzelspitze, die REGR-Halbwertsbreite und die Länge der Wachstumszone sich bei den vier untersuchten Arten auf die gleiche Weise proportional zur Geschwindigkeit der Spitze (VSpitze) verhalten. Es konnte auch gezeigt werden, dass die oben genannten Wachstumsparameter sowie VSpitze in linearer Weise vom Wurzeldurchmesser abhängen. Die untersuchten Arten weisen keinen diurnalen Rhythmus des Wurzelwachstums auf. An Maiswurzeln konnte bei Versuchen unter konstanten sowie rasch veränderten Umgebungsbedingungen gezeigt werden, dass die Symmetrie der relativen Wuchsratenverteilung vom externen Nährstoffangebot abhängt. Auch die Wachstumsleistung der Primärwurzelspitze wird durch die umgebende Nährstoffkonzentration beeinflusst. Je höher die Konzentration ist, desto schneller nimmt die Wachstumsleistung ab. Erstmals konnte die dynamische Reaktion der Primärwurzeln auf rasche Variation der Nährstoffverfügbarkeit mit hoher raum-zeitlicher Auflösung untersucht werden. Bei der dynamischen Reaktion der Wurzel auf die veränderten Bedingungen werden fast ausschließlich REGRmax und VSpitze variiert. Das Ausmaß der Wachstumsveränderung ist geringer abhängig von der veränderten Osmolarität als von der Nährstoffkonzentration– sowohl von der Ausgangskonzentration als auch von der absoluten Veränderung. Dies legt einen Zusammenhang der Wachstumsreaktion mit der Nährstoffaufnahme nahe. Durch den Einsatz einer stabil transformierten Arabidopsis-Linie mit einem labilen Reportergen-Konstrukt konnte die Dynamik des G2/M-Übergangs (und damit der Zellteilungsaktivität) in vivo ohne externe Behandlung untersucht werden. Für die Zellteilungsaktivität und Meristemlänge wurde mit dieser Methode eine lineare Abhängigkeit von der Spitzengeschwindigkeit der Wurzel festgestellt

Some thoughts on recreation geography in Alaska From a physio-climatic viewpoint

A possible analysis of Alaska's climate in relation to its physiological and psychological impact on man cannot be developed by utilizing existing, traditional climatic systems ·which base their fin dings largely on annual averages of temperatures and precipitation, leaving man (and the potential tourist) standing on the sidelines. This brief study attempts to throw light on Alaska's recreational potential as it might be related to climatology. To accomplish this purpose, this paper utilizes a physio-climatic system which was previously originated by the writer. This scheme in tegrates the physiological and psychological reactions of the average person to maximum and minimum temperatures, maximum and minimum relative humidities, solar radiations, and wind chills. These considerations were applied to daytime and nighttime for certain selected months. Thus, "real" conditions rather than annual averages are stressed. An annual map of climates is considered to be unsatisfactory and too much of a generalization, since climates are viewed as dynamic phenomena which migrate over the surface of this planet on a seasonal basis. This latter fact should be appreciated especially in a region like Alaska where seasonal extremes can be considerable and demand a high price in human psycho-physiological endurance.The California Geographer 9: 27-3

Pulsed electric fields and meat processing: latest updates

Pulsed electric fields (PEF) is a non-thermal technology that is still looking for implementation on a larger scale by the meat industry. Its sustainability dimension, which is much improved by lowering energy consumption and shortening treatment times compared to conventional technologies, may tip the scale for successfully shifting the PEF technology readiness level to industrial application. This review provides an overview of the latest knowledge, and in the last three years, on using PEF processing in meat to enhance its functionality, nutrition, texture, colour and sensory quality. PEF treatment could improve meat’s protein digestibility and solubility while having no negative impact on its nutritional value. However, controversial indications regarding PEF’s effect on meat cooking loss are reported. Colour changes of meat after PEF treatment are directly proportional to the extent of total specific energy inputs used in the processing, while the effect of PEF on meat sensory properties is yet to be discovered. Since the ability of PEF to achieve its desired goals is dependent on many different factors, including the type of meat, electric field strength, number and duration of electric pulses, and others, more studies are needed to fully understand specific conditions that can be dependably applied in the meat industry.Highlightspulsed electric fields improve functional quality of meatpulsed electric fields do not negatively affect nutritional quality of meatpulsed electric fields sustainability research in meat industry is hugely missin

Life cycle assessment of hemp-based milk alternative production in Lower Saxony, Germany, based on a material flow analysis of a pilot scale

Purpose: Recently, demand for plant-based milk products (PBMP) has increased for multiple reasons, such as the rapid population growth expected to reach 9.7 billion by 2050, health concerns such as lactose intolerance, nutritional aspects, ethical reasons, and environmental concerns. This leads to increased demand for food and competition for natural resources. Hemp-based milk is an emerging dairy alternative, and stakeholders in the supply chain are becoming increasingly interested in learning about the environmental effects of its production. This article aims for a comparative life cycle assessment of hemp-based and bovine milk with fat and protein correction to account for the differences in macronutrient content. Methods: The cradle-to-factory gate LCA relied on experimental cultivation and milk production in Lower Saxony, Germany. Inventory was based on primary data from fields and the pilot plant of DIL e. V. and on literature and ecoinvent database to develop a life cycle assessment (LCA) model. The LCA was performed using Simapro 9.3 software and IMPACT 2002+ impact assessment method. The life cycle stages include cultivation, harvesting, and milk production. The study compared hemp-based milk to bovine milk based on 1 kg fat and protein-corrected milk (FPCM) as a functional unit (FU). Co-products are taken into consideration using mass-economic allocation. Results: The results showed that hemp cultivation accounted for the highest impact (99%) in the production chain of hemp milk production. The GWP of 1 kg of FPCM hemp-based milk is 0.42 kg CO2 eq. The energy consumption for 1 kg of FPCM hemp-based milk is 4.73 MJ (12.26% lower than bovine milk). The other main factors impacting hemp-based milk production were terrestrial ecotoxicity (6.444E2 kg TEG soil) and aquatic ecotoxicity (2.458E2 kg TEG water). Hemp fiber was the co-product with 40% of the allocated impacts. The results are sensitive to the changes in fat-protein contents, functional unit, and system boundaries. The results demonstrated that the impacts of hemp milk production were within the range indicated for other PBMP production and 51.7% lower than bovine milk production in terms of GWP. This range primarily stems from field emissions, fertilizer application, and machinery usage during cultivation and harvest. Conclusion: The results of the comparisons of bovine milk and hemp-based milk were dependable on the FU. The hemp-based milk has the potential to be a more sustainable alternative to bovine milk due to considerably lower impacts in impact categories—land occupation (99% lower than bovine milk), global warming (52% lower than bovine milk), and ionizing radiation (23% lower than bovine milk). It is primarily due to less use of agricultural machinery, less land requirement, and lower NH3 emissions than bovine milk in various stages of milk production.info:eu-repo/semantics/publishedVersio

Renal impairment after liver transplantation - a pilot trial of calcineurin inhibitor-free vs. calcineurin inhibitor sparing immunosuppression in patients with mildly impaired renal function after liver transplantation

<p>Abstract</p> <p>Objectives</p> <p>Chronic kidney disease is frequent in patients after orthotopic liver transplantation (OLT) and has impact on survival. Patients receiving calcineurin inhibitors (CNI) are at increased risk to develop impaired renal function. Early CNI reduction and concomitant use of mycophenolat mofetil (MMF) has been shown to improve renal function.</p> <p>Methods</p> <p>The aim of this trial was to compare dose-reduced CNI/MMF versus CNI-free MMF/prednisone-based treatment in stable patients after OLT with respect to glomerular filtration rate (GFR). 21 patients [GFR 44.9 ± 9.9 mL/min/1.73 m²measured by 99m-Tc-DTPA-clearance, serum creatinine (SCr) 1.5 ± 0.42 mg/dL] were randomized either to exchange CNI for 10 mg prednisone (group 1; n = 8) or to receive CNI at 25% of the initial dose (group 2; n = 13) each in combination with 1000 mg MMF b.i.d.</p> <p>Results</p> <p>At month 12 mean SCr (-0.3 ± 0.4 mg/dL, p = 0.031) and GFR improved (8.6 ± 13.1 mL/min/1.73 m², p = 0.015) in group 2 but remained unchanged in group 1. Main side effects were gastroinstestinal symptoms (14.3%) and infections (4.8%). Two biopsy proven, steroid-responsive rejections occurred. In group 1 mean diastolic blood pressure (BP) increased by 11 ± 22 mmHg (p = 0.03).</p> <p>Conclusions</p> <p>Reduced dose CNI in combination with MMF but not CNI-free-immunosuppression leads to improvement of GFR in patients with moderately elevated SCr levels after OLT. Addition of steroids resulted in increased diastolic blood pressure presumably counterbalancing the benefits of CNI withdrawal on renal function.</p