Release of K-, Cl- und S-Species during Co-Combustion of Coal and Straw

Straw as a renewable energy source can either be used alone or be used in existing coal-fired power plants (co-combustion). The objective of the present work was to investigate the influence of fuel composition and interactions between various types of straw and coal on the release of K, Cl, and S species during co-combustion of coal and straw at temperatures between 800 and 1100 degrees C. The amount of HCl released during co-combustion was higher than expected on the basis of the combustion results of the pure fuels because of the reaction of the straw KCl with the coal silica. However, the amount of potassium released in gaseous form is only slightly lower than expected. The relative amount of sulfur released during co-combustion in comparison to the expected amount depends upon the temperature and the biomass share of the blends. At higher temperatures or lower straw share, the release is increased because of the reaction of the straw K2SO4 with the coal clay minerals. At lower temperatures and high straw share, available straw potassium and calcium capture some coal sulfur

Is the Gut Microbiome a Target for Adjuvant Treatment of COVID-19?

High expression of the transmembrane protein angiotensin I converting enzyme 2 (ACE2), more than 100-times higher as in the lung, and transmembrane serine protease 2 (TMPRSS2) in the gastrointestinal tract leads to infection with SARS-CoV-2. According to meta-analysis data, 9.8–20% of COVID-19 patients experience gastrointestinal symptoms, where diarrhoea is the most frequent, and about 50% shed viruses with high titre through their faeces, where a first faecal transmission was reported. Furthermore, gut inflammation, intestinal damage, and weakening of the gut mucosal integrity that leads to increased permeability has been shown in different studies for COVID-19 patients. This can lead to increased inflammation and bacteraemia. Low mucosal integrity combined with low intestinal damage is a good predictor for disease progression and submission to the intensive care unit (ICU). Several pilot studies have shown that the gut microbiome of COVID-19 patients is changed, microbial richness and diversity were lower, and opportunistic pathogens that can cause bacteraemia were enriched compared to a healthy control group. In a large proportion of these patients, dysbiosis was not resolved at discharge from the hospital and one study showed dysbiosis is still present after 3 months post COVID-19. Consequently, there might be a link between dysbiosis of the gut microbiome in COVID-19 patients and chronic COVID-19 syndrome (CCS). Various clinical trials are investigating the benefit of probiotics for acute COVID-19 patients, the majority of which have not reported results yet. However, two clinical trials have shown that a certain combination of probiotics is beneficial and safe for acute COVID-19 patients. Mortality was 11% for the probiotic treatment group, and 22% for the control group. Furthermore, for the probiotic group, symptoms cleared faster, and an 8-fold decreased risk of developing a respiratory failure was calculated. In conclusion, evidence is arising that inflammation, increased permeability, and microbiome dysbiosis in the gut occur in COVID-19 patients and thus provide new targets for adjuvant treatments of acute and chronic COVID-19. More research in this area is needed

Use of Peptide Libraries for Identification and Optimization of Novel Antimicrobial Peptides.

The increasing rates of resistance among bacteria and to a lesser extent fungi have resulted in an urgent need to find new molecules that hold therapeutic promise against multidrug-resistant strains. Antimicrobial peptides have proven very effective against a variety of multidrug-resistant bacteria. Additionally, the low levels of resistance reported towards these molecules are an attractive feature for antimicrobial drug development. Here we summarise information on diverse peptide libraries used to discover or to optimize antimicrobial peptides. Chemical synthesized peptide libraries, for example split and mix method, tea bag method, multi-pin method and cellulose spot method are discussed. In addition biological peptide library screening methods are summarized, like phage display, bacterial display, mRNA-display and ribosomal display. A few examples are given for small peptide libraries, which almost exclusively follow a rational design of peptides of interest rather than a combinatorial approach

Is There a Connection Between Gut Microbiome Dysbiosis Occurring in COVID-19 Patients and Post-COVID-19 Symptoms?

According to WHO, currently 215 countries/areas/territories report a total of more than 176 million confirmed COVID-19 cases and 3.8 million deaths (June 18, 2021). SARS-CoV-2, the causative agent of COVID-19, does not impact only the respiratory system but also the various organs in the body. It can directly or indirectly affect the pulmonary system, cardiovascular system (including heart failure), renal system (including kidney failure), hepatic system (including liver failure), gastrointestinal system, nervous system, and/or various systems, leading to shock and multi-organ failure (Zaim et al., 2020). In consequence, comorbidity in these systems leads to a higher risk for a severe disease progression

Cäsium-Sorptionsuntersuchungen an graphitischen Reaktorwerkstoffen

A Knudsen cell-mass spectrometer System has been developed for vapour pressure measurements to determine the sorption isotherms of Cs for graphitic reactor materials. Double Knudsen cells heated by high frequency were employed in this system. A highvacuum furnace with a specially designed oven-cell was used for isopiestic experiments carried out in addition ta the mass spectrometric studies. The Cs equilibrium partial pressure was measured at temperatures 950 and 1820 K oves A3-3 fuel elementmatrix with Cs concentrations between 0.17 and 34.76 mma1/kg. Sorptionisotherms of Cs according to Henry and Freundlich wereevaluated from the vapour pressure data. The sorption enthalpies for CsTob tained indicahte a strong boned by chemisorption. Cssorption of the "reactor graphites" A3-3, A3-27, ASR -1RG, ASR-1RS, ASR-2RS, PAN, P3-JHAN, PXA-2N, H-451, H-327, IG-110 and thecoat-mix materials Cm-100 and Cm-30 resulted by the isopiestic method. It could be shown that graphitic reactor materials wich phenolic resin binder are able to bind a substantially higher amount of Cs by sorption than "reactor graphites" without this binder. More information about the content of this report is given in chapter 8 "Zusammenfassung und Ausblick" (Summary and outlook)

A short artificial antimicrobial peptide shows potential to prevent or treat bone infections.

Infection of bone is a severe complication due to the variety of bacteria causing it, their resistance against classical antibiotics, the formation of a biofilm and the difficulty to eradicate it. Antimicrobial peptides (AMPs) are naturally occurring peptides and promising candidates for treatment of joint infections. This study aimed to analyze the effect of short artificial peptides derived from an optimized library regarding (1) antimicrobial effect on different bacterial species, (2) efficacy on biofilms, and (3) effect on osteoblast‑like cells. Culturing the AMP-modifications with Escherichia coli, Enterococcus faecalis, Pseudomonas aeruginosa, Staphylococcus aureus (including clinical isolates of MRSA and MSSA) and Staphylococcus epidermidis identified one candidate that was most effective against all bacteria. This AMP was also able to reduce biofilm as demonstrated by FISH and microcalorimetry. Osteoblast viability and differentiation were not negatively affected by the AMP. A cation concentration comparable to that physiologically occurring in blood had almost no negative effect on AMP activity and even with 10% serum bacterial growth was inhibited. Bacteria internalized into osteoblasts were reduced by the AMP. Taken together the results demonstrate a high antimicrobial activity of the AMP even against bacteria incorporated in a biofilm or internalized into cells without harming human osteoblasts

Collateral damage associated with performance-based pay: the role of stress appraisals

© 2019 Informa UK Limited, trading as Taylor & Francis Group. Drawing on stress appraisal and self-determination theories, we hypothesized that the more requirements of performance-based pay are appraised as a challenge, the more individuals will feel less strain and be more prosocial, and that these effects will be explained by autonomous motivations. Conversely, the more requirements of performance-based pay are appraised as a hindrance, the more individuals will feel more strain and be less prosocial, and these effects will be explained by controlled motivations. An experiment (N = 82) provided support for the mediational hypotheses regarding challenge appraisal, intrinsic motivation, and the strain outcomes of anxiety and fatigue. Hindrance appraisal was found to directly reduce prosocial behaviour (as coded in task responses). Furthermore, in reward conditions that were directly performance-salient, hindrance appraisal resulted in greater fatigue. A field study (N = 322) revealed further support for the hypotheses on emotional exhaustion and organizational citizenship. Overall, there was support for the role of autonomous forms of motivation as mechanisms in these associations, but less support for controlled forms of motivation. Thus, stress appraisals of performance-based pay can improve our understanding of when “collateral damage” effects of extrinsic rewards can occur (i.e., when requirements are viewed as hindering). Moreover, effects of stress appraisals can be partially explained by different qualities of motivation from the self-determination theory perspective

Comparison of a Short Linear Antimicrobial Peptide with Its Disulfide-Cyclized and Cyclotide-Grafted Variants against Clinically Relevant Pathogens.

According to the World Health Organization (WHO) the development of resistance against antibiotics by microbes is one of the most pressing health concerns. The situation will intensify since only a few pharmacological companies are currently developing novel antimicrobial compounds. Discovery and development of novel antimicrobial compounds with new modes of action are urgently needed. Antimicrobial peptides (AMPs) are known to be able to kill multidrug-resistant bacteria and, therefore, of interest to be developed into antimicrobial drugs. Proteolytic stability and toxicities of these peptides are challenges to overcome, and one strategy frequently used to address stability is cyclization. Here we introduced a disulfide-bond to cyclize a potent and nontoxic 9mer peptide and, in addition, as a proof-of-concept study, grafted this peptide into loop 6 of the cyclotide MCoTI-II. This is the first time an antimicrobial peptide has been successfully grafted onto the cyclotide scaffold. The disulfide-cyclized and grafted cyclotide showed moderate activity in broth and strong activity in 1/5 broth against clinically relevant resistant pathogens. The linear peptide showed superior activity in both conditions. The half-life time in 100% human serum was determined, for the linear peptide, to be 13 min, for the simple disulfide-cyclized peptide, 9 min, and, for the grafted cyclotide 7 h 15 min. The addition of 10% human serum led to a loss of antimicrobial activity for the different organisms, ranging from 1 to >8-fold for the cyclotide. For the disulfide-cyclized version and the linear version, activity also dropped to different degrees, 2 to 18-fold, and 1 to 30-fold respectively. Despite the massive difference in stability, the linear peptide still showed superior antimicrobial activity. The cyclotide and the disulfide-cyclized version demonstrated a slower bactericidal effect than the linear version. All three peptides were stable at high and low pH, and had very low hemolytic and cytotoxic activity