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We investigate the spectral properties of a non-Hermitian quasi-one-dimensional lattice in two possible dimerization configurations. Specifically, we focus on a non-Hermitian diamond chain that presents a zero-energy flat band. The flat band originates from wave interference and results in eigenstates with a finite contribution only on two sites of the unit cell. To achieve the non-Hermitian characteristics, we introduce non-reciprocal intrasite hopping terms in the chain. This leads to the accumulation of eigenstates on the boundary of the system, known as the non-Hermitian skin effect. Despite this accumulation of eigenstates, for one of the two possible configurations, we can characterize the presence of non-trivial edge states at zero energy by a real-space topological invariant known as the biorthogonal polarization. We show that this invariant, evaluated using the destructive interference method, characterizes the non-trivial phase of the non-Hermitian diamond chain. For the other possible non-Hermitian configuration, we find that there is a finite quantum metric associated with the flat band. Additionally, we observe the skin effect despite having the system a purely real or imaginary spectrum. For both configurations, we show that two non- Hermitian diamond chains can be mapped into two models of the Su-Schrieffer-Heeger chains, either non-Hermitian and Hermitian, in the presence of a flat band. This mapping allows us to draw valuable insights into the behavior and properties of these systems., Comment: 14 pages, 9 figures

In Austria, around 7 million m³ sawmill by-products (SBP) are produced each year and further processed mainly by the paper, panel and pellet industry. Since competition in demand has increased in the last decades, this article aims to provide an analysis of the Austrian SBP market. For this purpose, a simple econometric supply and demand model was estimated based on annual data (2001 – 2020) by using a “two-stage-least-squares” (2SLS) method. Besides the prices, supply is mainly determined by the instrument variable “sawnwood exports”, while demand is mainly explained by SBP input in panel and in pellet production. The model was further used to showcase its application for scenario analysis by calculating a reference and a bioeconomy scenario up to 2050. The reference scenario, assuming a continuation of recent trends, results in growing supply and decreasing demand, caused by rising prices. In contrast, the bioeconomy scenario results in a positive trend for both supply and demand in the long-term. Therefore, a growing importance of SBP for Austrian industries can be expected in a bioeconomy setting. Based on these examples, the estimated model can be seen as a basis for understanding the interrelationships in the SBP market and illustrating possible future developments., Proceedings of the 30th European Biomass Conference and Exhibition, 9-12 May 2022, Online, pp. 309-313

The reduction of greenhouse gas emissions is an important issue for iron and steel industry. One possibility is to use biomass-based reducing agents, also called bioreducers, to replace at least partly the fossil reducing agents. Modern blast furnaces use pulverized coal which is conveyed pneumatically in dense phase flow regime and injected into the blast furnace to substitute the more expensive coke. The substitution of this reducing agent by pulverized biochar is the target of the present study. Samples of different wood types were pyrolyzed under varying treatment intensities and finely ground with varying comminution techniques. The properties of the pyrolyzed wood powders were investigated. It is shown that the fluidization behaviour substantially improved with higher particle sphericity and lower proportion of ultrafine grains. Moreover, data show that by varying the pyrolysis temperature and employed comminution forces these powder characteristics are modified to an extent sufficient to produce well fluidizable bioreducers., Proceedings of the 29th European Biomass Conference and Exhibition, 26-29 April 2021, Online, pp. 1053-1056

Vertical price cointegration was analyzed in the Austrian sawmill industry by focusing on by-products. Hence, monthly price data for sawlogs, pulpwood, sawnwood, wood chips, sawdust, wood pellets and particle board were used for the following statistical tests: (1) The Johansen cointegration test was applied to all the time series combinations. (2) Cointegrated time series were tested for Granger causality. (3) Price influences resulting from (1) and (2) were used to estimate Vector Error Correction Models (VECM) for sawdust and wood chip prices. This enabled us to analyze the long-term and short-term behavior of cointegrated time series. Results showed vertical price cointegration within the sawmill industry (sawlogs and sawnwood) as well as influences of sawmill by-products on sawnwood prices. Furthermore, the wood pellet market is influencing sawmill by-product and sawnwood prices as well. VECM estimations suggest that sawdust prices are only influenced by pellet prices and thus recover faster from price shocks (23.5% per month). In contrast, wood chip prices are highly interlinked and thus recover only by 7.8% per month after price shocks., Proceedings of the 29th European Biomass Conference and Exhibition, 26-29 April 2021, Online, pp. 1122-1126

The reduction of greenhouse gas emissions is an important issue for iron and steel industry. One possibility is to use biomass-based reducing agents, also called bioreducers, to replace at least partly the fossil reducer agents. In a first step woody biomass was treated in a lab-scale muffle furnace and afterwards ground with a ball mill. The powder characteristics were investigated in respect to the flow behavior. For a certain treatment temperature, the particle size distribution and as well the flow behavior shows similarities to lignite. The next stage was to identify relations between powder characteristics and its fluidization behavior. A fluidization device was assembled and used to determine the minimum fluidization gas velocity for various bioreducer powders., Proceedings of the 28th European Biomass Conference and Exhibition, 6-9 July 2020, Virtual, pp. 574-576

Logical argumentation is a well-known approach to modelling nonmonotonic reasoning with conflicting information. In this paper we provide a proof-theoretic study of properties of logical argumentation frameworks. Given some desiderata in terms of rationality postulates, we consider the conditions that an argumentation framework should fulfill for the desiderata to hold. The rationality behind this approach is to assist designers to “plug-in” pre-defined formalisms according to actual needs. This work extends related research on the subject in several ways: more postulates are characterized, a more abstract notion of arguments is considered, and it is shown how the nature of the attack rules (subset attacks versus direct attacks) affects the properties of the whole setting.

The reduction of greenhouse gas emission is an important issue for steel industry. One possibility is to use biomass-based reducing agents, also called bioreducers, to replace a least partly the fossil reducer agents. To produce bioreducer we treated woody biomass in a lab-scale muffle furnace, we performed grinding experiments with a ball mill, we analyzed the particle size distribution with laser diffraction and we used a rotating device, the revolution powder analyzer, for flow behavior investigations. Our preliminary results show that treatment temperatures >250 oC bring adequate increased calorific value and improved grindability. For a certain treatment temperature the particle size distribution and as well the flow behavior shows similarities to lignite., Proceedings of the 27th European Biomass Conference and Exhibition, 27-30 May 2019, Lisbon, Portugal, pp. 1199-1201

To decarbonise the energy system in the future, a mix of different measures will be necessary. To assess possible measures (e.g. change to a new biomass boiler), different alternative technologies in the heating and mobility sectors were compared with fossil reference technologies in terms of costs and greenhouse gas (GHG) emission savings. The results showed that the largest GHG emission reduction is related to solid biomass boilers when substituting an oil boiler, at the same time saving costs. For the mobility sector an electric car operated with 100% renewable electricity results in best GHG emission reduction when replacing a diesel or gasoline passenger car, but with additional costs in comparison., Proceedings of the 27th European Biomass Conference and Exhibition, 27-30 May 2019, Lisbon, Portugal, pp. 1654-1657

Einführung: Die Einführung des Prostatascreenings mittels Prostata-spezifischen Antigen (PSA) -Test führte zur Steigerung der Früherkennung des Prostatakarzinoms und zu einer Verringerung der Metastasierung bei Diagnosestellung. Doch nicht jeder Patient hat dasselbe Risiko für[zum vollständigen Text gelangen Sie über die oben angegebene URL], 43. Gemeinsame Tagung der Österreichischen Gesellschaft für Urologie und Andrologie und der Bayerischen Urologenvereinigung

Reactive nitrogen (Nr) raises big concerns particularly in form of Nitrogen Oxide (NOx) since it causes direct and indirect (as precursor) harm to society and environment. Also for the thermal use of biomass there have been intensive debates, but no study so far has quantified the impact of Nitrogen. Therefore a better understanding of how nitrogen performs along the biomass combustion cycle (i.e. from tree to emission) should be gained. Based on a literature study and own data we investigated the impact of small scale biomass combustion on the anthropogenous N-cycle. Our results show that only 50 % of nitrogen contained in fuel wood (i.e. spruce) are emitted as NOx into the atmosphere, the other 50 % are released as harmless N2. Furthermore our model shows that trees take up 50 % more N out of the atmosphere than what is emitted during combustion., Proceedings of the 25th European Biomass Conference and Exhibition, 12-15 June 2017, Stockholm, Sweden, pp. 1788-1791

Science.Research.Pannonia. 12 Energie-Umweltmanagement

Fragestellung: Vergleich der postoperativen Evaluierung der plastisch-chirurgischen wie funktionellen Ergebnisse von kindlichen Hypospadieoperationen zwischen Kinderurologen und Eltern. Methodik: Nach einem entsprechenden Ethikvotum wurden 30 Kinder mit einem medianen Alter von 15.5 Monaten zum Zeitpunkt[for full text, please go to the a.m. URL], 41. Gemeinsame Tagung der Österreichischen Gesellschaft für Urologie und Andrologie und der Bayerischen Urologenvereinigung

Fragestellung: Entsprechend den kinderurologischen guidelines besteht kein Konsensus bzgl. der Indikation zu einer MCUG (Miktionszystourethrographie) nach Harnwegsinfekten (HWIs). Aufgrund einer mehr als 50% Wahrscheinlichkeit eines negativen MCUGs nach einem HWI werden primär alternative [for full text, please go to the a.m. URL], 41. Gemeinsame Tagung der Österreichischen Gesellschaft für Urologie und Andrologie und der Bayerischen Urologenvereinigung

In recent years the demand for wood fuels increased steadily, stimulated by public policies to deploy renewable energy technologies. In particular, wood pellet prices have been rising in recent years due to the increasing demand for wood pellets in the residential heating sector. This price increase causes rising heating costs for households using pellets as fuel. Hence, the question arises whether increasing wood pellet prices make hybrid heating systems such as combining pellet heating systems with solar thermal systems more competitive. Consequently, we aim at quantifying the effect of rising wood pellet prices on heat generation costs of conventional pellet systems and pellet-solar thermal systems. The results show that if pellet prices continue to rise at a rate of the last five years, pellet-solar thermal systems used in private households will become competitive despite the high investment costs., Proceedings of the 23rd European Biomass Conference and Exhibition, 1-4 June 2015, Vienna, Austria, pp. 1380-1383

Fragestellung: Die gängigste Technik der offenen Harnleiterneuimplantation bei Kindern ist die Methode nach Cohen. In der Literatur sind Erfolgsraten nach dieser Antirefluxplastik bis zu 99% dokumentiert. Die Methode nach Mathisen wird an den erwähnten beiden Abteilungen seit insgesamt[for full text, please go to the a.m. URL], 41. Gemeinsame Tagung der Österreichischen Gesellschaft für Urologie und Andrologie und der Bayerischen Urologenvereinigung

The pellet markets and pellet boiler installations have been rapidly developed in many countries sincea decade. Hence, the objective of this analysis is toforecast potential future developments of pellet boiler installations and to assess the coherent environmental impacts in Austria. First, a regression analysis with historical time series data is conducted considering different heating fuel prices and subsidies. Second, the regression results are used to develop four different forecast scenarios for pellet boiler installations in Austria. Third, the environmental impacts of the forecastsare assessed bydata in the literature and national emission inventories. The results show that heating oil price and pellet price influence pellet boiler installations significantly. Depending on the future price developments, between90,000 and 430,000 pellet boilers are forecasted to be installed in Austria until 2030. The environmental impact assessment reveals large saving potentials in GHG emissions and fossil fuel consumptions, but thehuman toxicity and tropospheric ozone precursor potential would likely increase. The results also indicate that pellets trade will gain on importance and environmental impacts are sensitive on the transportation system, which is currently based on trucks., Proceedings of the 23rd European Biomass Conference and Exhibition, 1-4 June 2015, Vienna, Austria, pp. 1521-1527

Unresectable hepatocellular carcinoma (HCC) are associated with a poor prognosis. Recently, one controlled study reported a strikingly prolonged survival of patients with HCC who were treated with octreotide. Until other randomised controlled trials become available, this multicentric retrospective study therefore assesses the outcome of HCC-patients who received octreotide treatment. 63 patients (53 males, 10 females) who had been treated with octreotide at 13 participating German centres were included in the analysis. In 54 cases liver cirrhosis was present (25 Child-Pugh A, 20 Child-Pugh B, 7 Child-Pugh C, 2 unknown). The liver disease was associated with alcohol abuse in 19 patients, alcohol and viral hepatitis in four patients, while 12 patients had only markers of past or present hepatitis B infection, 11 patients suffered of chronic hepatitis C infection, and four patients were seropositive for both hepatitis B and hepatitis C markers. The Okuda stage was stage I in 23, stage II in 33, and stage III in 7 patients. The patients initially received octreotide as a long-acting release formula (20-30 mg/month) in 43 cases or through subcutaneous injection (dose 3 x 50-3 x 300 ug/day) in the remaining cases. 11 of the patients receiving subcutaneous treatment were later converted to the long-acting release form of the drug. At three months, a partial remission was achieved in two patients, while 22 tumours showed no change and 26 tumours progressed. At six months, 11 tumours showed no change, while 15 tumours progressed. The patients' median survival was 9 months (Okuda stage I 16 months, stage II 9 months, stage III 4 months). In conclusion, octreotide treatment did not result in markedly prolonged survival in this retrospective series of 63 patients.