Half a century of research on diatoms in athalassic habitats in central Poland

The authors would like to dedicate this paper to Prof. Marcin Pliński who started the phycological research in these unique habitats of Central Poland.Part of the geology in the Łódź province was formed during the Upper Permian period when rich Zechstein salt was deposited. Groundwater drains the deposits and flows out in the village of Pełczyska, creating a unique hydrogeological site in Central Poland. An inland, athalassic ecosystem can be a reference site for halophile microflora. The outflow with surrounding marshes has been an algological research site since 1964. The research reveals changes recorded in diatom assemblages from athalassic habitats, characterized by a wide range of salinity levels, and verifies the tolerance of taxa to salinity. The comparative analysis was based on the diatom material sampled in 1964-1965, 1992-1994 and on recently collected samples. The analysis revealed the temporal change in assemblages caused by a change in the chloride concentration, and the spatial change from one to another habitat type, characterized by varying salinity levels. The halophilic species in the studied habitats included e.g. Halamphora dominici, H. tenerrima, Navicula digitoconvergens, N. meulemansii, Staurophora salina. The analysis of changes allowed the verification of the species’ requirements and tolerance range to the salinity factor. Therefore, in the case of Fragilaria famelica and Halamphora sydowii, we propose a change in the halobion system classification

Cyanobacteria microflora in a limestone spring (Troniny spring, Central Poland)

The paper reports a study of cyanobacterial diversity in a cold-water limestone limnocrene in Central Poland. Samples were collected from 1998 to 2000 and in June 2012. The morphology, population characteristics and species composition of the cyanobacteria assemblages were investigated, and the frequency of taxa was recorded. The large number of taxa identified (30) reflects the microhabitat heterogeneity of this spring. Some species considered epiphytes grew on limestone rocks. The occurrence of the majority of the most frequent taxa was related to the physicochemical characteristics of the spring, but none of them can be considered obligatory crenobionts characteristic of limestone springs. The studied spring is a unique ecosystem with an interesting cyanobacteria microflora whose occurrence is attributable to the spring’s water chemistry, low temperature and variety of microhabitats

Persistent cyanobacteria blooms in artificial water bodies : an effect of environmental conditions or the result of anthropogenic change

Algal blooms are an emerging problem. The massive development of phytoplankton is driven partly by the anthropogenic eutrophication of aquatic ecosystems and the expansion of toxic cyanobacteria in planktonic communities in temperate climate zones by the continual increase in global temperature. Cyanobacterial harmful algal blooms (CyanoHABs) not only disturb the ecological balance of the ecosystem, but they also prevent the use of waterbodies by humans. This study examines the cause of an unusual, persistent bloom in a recreational, flow-through reservoir; the findings emphasize the role played by the river supplying the reservoir in the formation of its massive cyanobacterial bloom. Comprehensive ecosystem-based environmental studies were performed, including climate change investigation, hydrochemical analysis, and bio-assessment of the ecological state of the river/reservoir, together with monitoring the cyanobacteria content of phytoplankton. Our findings show that the persistent and dominant biomass of Microcystis was related to the N/P ratio, while the presence of Aphanizomenon and Dolichospermum was associated with the high-temperature end electric conductivity of water. Together with the increase in global temperature, the massive and persistent cyanobacterial bloom appears to be maintained by the inflow of biogenic compounds carried by the river and the high electric conductivity of water. Even at the beginning of the phenomenon, the reservoir water already contained cyanobacterial toxins, which excluded its recreational use for about half the year

Abiotic Determinants of the Historical Buildings Biodeterioration in the Former Auschwitz II – Birkenau Concentration and Extermination Camp

The paper presents the results of a study conducted at the Auschwitz-Birkenau State Museum in Oświecim on the occurrence of biodeterioration. Visual assessment of the buildings revealed signs of deterioration of the buildings in the form of dampness, bulging and crumbling plaster, and wood fiber splitting. The external surfaces, and especially the concrete strips and ground immediately adjoining the buildings, were colonized by bryophytes, lichens, and algae. These organisms developed most intensively close to the ground on the northern sides of the buildings. Inside the buildings, molds and bacteria were not found to develop actively, while algae and wood-decaying fungi occurred locally. The factors conducive to biological corrosion in the studied buildings were excessive dampness of structural partitions close to the ground and a relative air humidity of above 70%, which was connected to ineffective moisture insulation. The influence of temperature was smaller, as it mostly affected the quantitative composition of the microorganisms and the qualitative composition of the algae. Also the impact of light was not very strong, but it was conducive to algae growth

Pro Libris: Lubuskie Pismo Literacko-Kulturalne, nr 4 (2010)

145 s. : il., portr.

The Regulation of Sulfur Metabolism in Mycobacterium tuberculosis

Mycobacterium tuberculosis (Mtb) has evolved into a highly successful human pathogen. It deftly subverts the bactericidal mechanisms of alveolar macrophages, ultimately inducing granuloma formation and establishing long-term residence in the host. These hallmarks of Mtb infection are facilitated by the metabolic adaptation of the pathogen to its surrounding environment and the biosynthesis of molecules that mediate its interactions with host immune cells. The sulfate assimilation pathway of Mtb produces a number of sulfur-containing metabolites with important contributions to pathogenesis and survival. This pathway is regulated by diverse environmental cues and regulatory proteins that mediate sulfur transactions in the cell. Here, we discuss the transcriptional and biochemical mechanisms of sulfur metabolism regulation in Mtb and potential small molecule regulators of the sulfate assimilation pathway that are collectively poised to aid this intracellular pathogen in its expert manipulation of the host. From this global analysis, we have identified a subset of sulfur-metabolizing enzymes that are sensitive to multiple regulatory cues and may be strong candidates for therapeutic intervention

Evaluation of the applicability of nano-biocide treatments on limestones used in cultural heritage.

One of the main problems in the conservation of historical buildings and archaeological sites is theone caused by biodeterioration. Biopatina, biocrust or biofouling generate aesthetical changes andinduce degradation processes within the stone matrix. In this work, three treatments based on sil-ver nanoparticles and silver/titanium dioxide nanocomposites have been studied as potential biocidesfor limestones: citrate-stabilized silver nanoparticles, silver/TiO2nanocomposites and citrate-stabilizedsilver/TiO2nanocomposites. These treatments were synthesized following a bottom-up method, using ornot a stabilizing agent (citrate), and have been characterized by UV-Visible spectrophotometry, DynamicLight Scattering and Raman spectroscopy. These treatments were applied on limestones from three differ-ent Spanish quarries located in Utrera (Seville), El Puerto de Santa María (Cadiz) and Novelda (Alicante).The aesthetical modification of limestone surfaces was studied by colorimetric techniques and the effec-tiveness of protection against biofouling formation was tested using an accelerated biofouling growthassay. The best results were obtained for the treatments based on citrate-stabilized silver nanoparti-cles. The effectiveness of the treatments depends on their penetration depth in the stone matrix andin this study, we have used Laser Induced Breakdown Spectroscopy to determine the depth profilesof nanocomposite presence in the stone matrix. Our results demonstrate that nanocomposites basedon citrate-stabilized silver nanoparticles can be useful for the treatment of historical buildings andarchaeological sites made of limestone, without producing high colour increments. Additionally, we have demonstrated the suitability of Laser Induced Breakdown Spectroscopy for the detection of silver/TiO2nanocomposites and for the generation of depth profiles.Departamento de Sistemas Físicos, Químicos y Naturales, Universidad Pablo de Olavide,Departamento de Ingeniería Industrial II, laser Applications laboratory, Universidade da Coruña,Preprin

COVID-19 symptoms at hospital admission vary with age and sex: results from the ISARIC prospective multinational observational study

Background: The ISARIC prospective multinational observational study is the largest cohort of hospitalized patients with COVID-19. We present relationships of age, sex, and nationality to presenting symptoms. Methods: International, prospective observational study of 60 109 hospitalized symptomatic patients with laboratory-confirmed COVID-19 recruited from 43 countries between 30 January and 3 August 2020. Logistic regression was performed to evaluate relationships of age and sex to published COVID-19 case definitions and the most commonly reported symptoms. Results: ‘Typical’ symptoms of fever (69%), cough (68%) and shortness of breath (66%) were the most commonly reported. 92% of patients experienced at least one of these. Prevalence of typical symptoms was greatest in 30- to 60-year-olds (respectively 80, 79, 69%; at least one 95%). They were reported less frequently in children (≤ 18 years: 69, 48, 23; 85%), older adults (≥ 70 years: 61, 62, 65; 90%), and women (66, 66, 64; 90%; vs. men 71, 70, 67; 93%, each P < 0.001). The most common atypical presentations under 60 years of age were nausea and vomiting and abdominal pain, and over 60 years was confusion. Regression models showed significant differences in symptoms with sex, age and country. Interpretation: This international collaboration has allowed us to report reliable symptom data from the largest cohort of patients admitted to hospital with COVID-19. Adults over 60 and children admitted to hospital with COVID-19 are less likely to present with typical symptoms. Nausea and vomiting are common atypical presentations under 30 years. Confusion is a frequent atypical presentation of COVID-19 in adults over 60 years. Women are less likely to experience typical symptoms than men

Taksonomia i ekologia sinic (Cyanobacteria) źródeł zimnowodnych

Przedmiotem badań była różnorodność taksonomiczna i ekologiczna sinic występujących w źródłach zimnowodnych na czwartorzędowych utworach geologicznych Polski Środkowej. Badaniami objęto 10 obiektów krenologicznych w województwie łódzkim, o zróżnicowanym typie hydrobiologicznym – 6 reokrenów i 4 limnokreny. Dla obiektów określono stopień oddziaływania człowieka na nisze źródliskowe na podstawie zaproponowanej kategoryzacji, w celu scharakteryzowania stopnia przekształcenia obiektów krenologicznych. W odstępach comiesięcznych, od marca 2012 do lutego 2014 roku, zbierano próby do analizy algologicznej, z różnych typów mikrosiedlisk: bentosu, epilitonu, epiksylonu, peryfitonu, epilitonu z mchami, epiksylonu z mchami i peryfitonu z mchami oraz jednocześnie wykonywano w terenie pomiary parametrów takich, jak: temperatura, odczynu i przewodnictwo elektrolityczne wody. Dodatkowo w okresie zimy i lata pobrano próby wody do analizy wybranych parametrów chemicznych w laboratorium. Wykonano analizę jakościową sinic na podstawie tradycyjnych metod identyfikacji oraz oszacowano biomasę na podstawie średniej objętości komórek i form morfologicznych. Wielowymiarowe metody porządkowania danych wykorzystane zostały do opisu struktury taksonomicznej zbiorowisk i zbadania preferencji ekologicznych taksonów sinic względem: typu hydrobiologicznego źródeł, rodzaju mikrosiedlisk, pory roku, stopnia oddziaływania człowieka i parametrów chemicznych wód. W badanych źródłach zimnowodnych odnotowano występowanie 43 taksonów sinic, które w przeważającej części należały do form kokalnych (Chroococcales) – 19 i prostych form trychomowych (Oscillatoriales) – 17 oraz niewielkiej części form tworzących heterocyty (Nostocales) – 7. Źródła reokreniczne charakteryzowały się nieznacznie większą średnią liczbą taksonów – 14, niż źródła limnokreniczne – 12, jednak dla poszczególnych obiektów krenologicznych liczba taksonów była zróżnicowana – dla reokrenów od 3 do 22, a limnokrenów od 7 do 17. Zbiorowiskiem o najwyższej różnorodności taksonomicznej był peryfiton porastający podłoża betonowe wypływów limnokrenicznych, natomiast o najniższej – bentos. Peryfiton charakteryzował się również najmniejszą sezonową zmiennością liczby taksonów sinic. Duże różnice w liczbie taksonów zanotowano w mikrosiedliskach związanych z mchami, w których w okresie zimowym nie odnotowano występowania sinic. W badanych źródłach najczęściej i z największym udziałem notowano przedstawicieli rodzajów: Aphanocapsa, w tym A. fonticola; Chamaesiphon reprezentowany przez Ch. minutus, Ch. incrustans; Microcoleus: M. fonticola, M. amoenus, M. autumnalis, Phormidium: P. terebriforme, P. tinctorium oraz taksony: Heteroleiblenia kuetzingii, Lyngbya martensiana, Oscillatoria sp., Pseudanabaena minima i Tapinothrix janthina. Występowanie poszczególnych taksonów związane było z preferencjami w stosunku do typu hydrobiologicznego źródeł, jak i rodzaju mikrosiedlisk, jednak tylko w przypadku pojedynczych taksonów zaobserwowano związek występowania z porą roku. Przeprowadzona analiza BIO-ENV wskazała, że w największym stopniu zbiorowiska sinic kształtowane były przez zawartość jonów: amonowych, azotanowych, fosforanowych oraz odczyn wody. W związku z dużym wpływem bezpośrednim oraz pośrednim człowieka na badane obiekty krenologiczne, czynniki antropogeniczne miały decydujące znacznie przy kształtowaniu się zbiorowisk sinic w źródłach zimnowodnych Polski Środkowej