Inclusions of Amorphous and Crystalline SiO2 in Minerals from Itrongay (Madagascar) and Other Evidence for the Natural Occurrence of Hydrosilicate Fluids

Experimental studies increasingly often report low-temperature (200–800 °C) and low-pressure (0.05–3 kbar) hydrosilicate fluids with >40 wt.% of SiO2 and >10 wt.% of H2O. Compositionally similar fluids were long suggested to potentially exist in natural systems such as pegmatites and hydrothermal veins. However, they are rarely invoked in recent petrogenetic models, perhaps because of the scarcity of direct evidence for their natural occurrence. Here we review such evidence from previous works and add to this by documenting inclusions of hydrosilicate fluids in quartz and feldspar from Itrongay. The latter comprise opal-A, opal-CT, moganite and quartz inclusions that frequently contain H2O and have negative crystal shapes. They coexist with inclusions of CO2- and H2O-rich fluids and complex polycrystalline inclusions containing chlorides, sulphates, carbonates, arsenates, oxides, hydroxides and silicates, which we interpret as remnants of saline liquids. Collectively, previous studies and our new results indicate that hydrosilicate fluids may be common in the Earth’s crust, although their tendency to transform into quartz upon cooling and exhumation renders them difficult to recognise. These data warrant more comprehensive research into the nature of such hydrosilicate fluids and their distribution across a wide range of pressure and temperature conditions and geological systems.

Studies of ticks of the genus Dermacentor (Acari; Ixodidae) on the natural occurrence of tularemia pathogen in the conditions of the Central Pre-Caucasian region

The purpose of the research is the assessment of the Francisella tularensis occurrence in nature in ticks of the genus Dermacentor; understanding the physiological age in terms of tick infection with tularemia pathogen.Materials and methods. For the period from 2015 to 2019, we examined 8449 specimens of Dermacentor marginatus (916 pools), 8674 specimens of D. reticulatus (705 pools), and 109 specimens of D. niveus (40 pools) for tularemia infection. To assess the dependence of tularemia pathogen found in ticks of different physiological ages, we examined 2440 specimens of D. marginatus (360 pools), and 3349 specimens of D. reticulatus (412 pools) for the period from 2016 to 2019. Studies of ixodid ticks infected with tularemia pathogen were performed by the Natural Focal Infection Laboratory of the Stavropol Anti-Plague Institute. Pools of ixodid ticks were examined for the pathogen DNA of tularemia using reagent kits for identifying Francisella tularensis DNA by polymerase chain reaction with fluorescence hybridization of results recorded in real time.Results and discussion. The infection rate of the tularemia pathogen in ticks in the Central Pre-Caucasian region ranged from 0.044–1.127% in D. marginatus and 0.035–1.455% in D. reticulatus in different years. The greatest number of F. tularensis was isolated from the III physiological age ticks. For D. reticulatus ticks, no statistically significant dependence of the detected tularemia pathogen on physiological age was found.

Detection, in silico analysis and molecular diversity of phytoplasmas from solanaceous crops in Turkey

Phytoplasma-like symptoms of leaf yellowing and calyx malformation were observed in eggplant (Solanum melongena L.), upward leaves and fruit malformation in pepper (Capsicum annuum L.), and aerial tuber formation in potato (S. tuberosum L.) during the survey performed in the late season (August to September) of 2015 and 2016 in Van province (Turkey). A total of 100 samples were tested by nested-PCR using universal primer pairs to assess the sanitary status of the solanaceous crops and to characterise the phytoplasma isolates. Among them, seven samples resulted in a 1.25 kb DNA fragment, and five (two eggplants, two peppers, and one potato) were molecularly characterised (Accession No.: KY579357, KT595210, MF564267, MF564266, and MH683601). BLAST and the virtual restriction fragment length polymorphism (RFLP) analysis of 16S rRNA genes revealed the presence of two distinct phytoplasma infections in solanaceous crops: ‘Candidatus Phytoplasma trifolii’ a member of the clover proliferation group (16SrVI) and subgroup A and ‘Candidatus P. solani’ a member of the stolbur group (16SrXII) and subgroup A. The virtual RFLP analysis and calculated coefficients of RFLP pattern similarities further revealed a remarkable genetic diversity among the ‘Candidatus P. solani’ isolates infecting pepper (similarity coefficient of 0.90) and eggplant (similarity coefficients of 0.98 and 1.00) at the same geographical area. This is the first report of the natural occurrence of ‘Candidadtus P. trifolii’ in potato from the Eastern Anatolia region, Turkey.

The Cyclical Sine Model Explanation for Climate Change

This paper will show that the global warming/climate change underway on Earth today is a totally natural occurrence with solid scientific and historical support. The Earth is currently in the upswing part of its normal temperature cycle. Very warm (Medieval Warming) and very cold (Little Ice Age) cycles have been historically documented on Earth for at least the last 3,000 years. This cyclicity has a repeated period of approximately every 1,500 years [1]. The explanation for the Earth’s temperature increases since 1850 is captured in a mathematical model called the Cyclical Sine Model. This model fits past climate cycles, measured temperatures since 1850, and correlates closely with the thousand year cyclicity of solar activity from 14C/12C ratio studies [2], and Bond [3] Atlantic drift ice cycles. This model also agrees with sunspot history, the Atlantic Multidecadal Oscillation, and the Pacific Decadal Oscillation. In addition, this model quantitively explains the time span 1945-1975 when an impending ice age was feared [4]. Earth temperatures are controlled by three solar cycles of approximately 1,000, 70, and 11 years. The Cyclical Sine Model is the best explanation for the Earth’s recent temperature increases.

Crystal Structure Algorithm (CryStAl) Based Selective Harmonic Elimination Modulation in a Cascaded H-Bridge Multilevel Inverter

This paper introduces an effective Selective Harmonic Elimination (SHE) modulation technique in a five, seven, and nine-level cascaded H-bridge (CHB) multilevel inverter (MLI). Minimization of the harmonics and device counts is the basis for the ongoing research in the area of MLI. Reduced harmonics and hence the lower Total Harmonic Distortion (THD), improve the output power quality. SHE is a low-frequency modulation scheme to achieve this goal. SHE techniques are used to eliminate the distinct lower-order harmonics by determining the optimum switching angles. These angles are evaluated by solving the non-linear transcendental equations using any optimization technique. For this purpose, the Crystal Structure Algorithm (CryStAl) has been used in this paper. It is a metaheuristic, nature-inspired, and highly efficient optimization technique. CryStAl is a simple and parameter-free algorithm that doesn’t require the determination of any internal parameter during the optimization process. It is based on the concept of crystal structure formation by joining the basis and lattice point. This natural occurrence can be realized in crystalline minerals in their symmetrically organized components: ions, atoms, and molecules. The concept has been utilized to solve non-linear transcendental equations. SIMULINK/MATLAB environment has been used for the simulation. The simulation result shows that the crystal structure algorithm is very effective and excels the other metaheuristic algorithm. Hardware results validate the performance.

Natural Occurrence of Ochratoxin A in Spices Marketed in the Czech Republic during 2019–2020

Spices are a popular ingredient in cuisine worldwide but can pose a health risk as they are prone to fungal infestation and mycotoxin contamination. The purpose of this study was to evaluate ochratoxin A (OTA) in 54 single-kind traditional and less traditional spices, each of which was purchased in six samples of different batches (324 samples in total) at the Czech market during 2019–2020. The HPLC-FLD method with pre-treatment by immunoaffinity columns was employed to determine OTA. The limits of detection and quantification were 0.03 ng g−1 and 0.10 ng g−1, respectively. A total of 101 (31%) samples of 19 spice kinds were positive at concentrations ranging from 0.11–38.46 ng g−1. Only turmeric was contaminated with an OTA level exceeding the European Union limits. However, most spices have no regulation, thus further extensive monitoring of various mycotoxins in various kinds of spices is necessary. Chilli and black pepper are the most studied spices for OTA contamination, however, many other kinds of spice can also be highly contaminated, but studies on them are less common, rare, or have not yet been performed. The uniqueness of this study lies in the wide range of spice types studied for the presence of OTA on the Czech market.

Comparative Efficacy of Two Antibiotics for the Management of Secondary Bacterial Infection in Goats Clinically Affected by Peste des Petits Ruminants

Aims: Peste des petits Ruminants (PPR) is a major viral disease that poses a challenge to small ruminant farming. Its natural occurrence has been complicated by secondary bacterial infection which has led to an increase in morbidity and mortality rates. This study reports the management outcome of natural PPR-infected goats using two types of antibiotics in Nsukka metropolis of Enugu State Nigeria. Methodology: Goats (N=24) were confirmed to be suffering from PPR based on clinical signs and using polymerase chain reaction (PCR). The animals were divided into two groups. Group A was treated with 20% oxytetracycline (N= 10) and group B with procaine penicillin and streptomycin combination (penstrept) (N= 14) injection. Clinical signs, recovery and survivability, temperature, haematology [Packed cell volume (PCV); haemoglobin concentration (Hbconc); red blood cell (RBC) and white blood cell (WBC) counts] and some serum biochemical profiles [alanine aminotransferase (ALT); aspartate transaminase (AST); total protein (TP); Albumin; urea; creatinine; potassium and sodium] were used to assess the efficacy of the antibiotics using standard techniques. Results: The mean temperature, RBC, WBC and urea values of the PPR-infected goats were above their reference ranges, mean albumin values were below the reference range while mean Hbconc, PCV, AST, ALT, TP and creatinine values were within their reference range before the commencement of treatment. Following treatment, clinical signs cleared in 20% and 35.7% of the goats treated with oxytetracycline and penstrep respectively. Death was recorded in 20% and 15% of goats treated with oxytetracycline and penstrep respectively before the end of treatment. Penstrep-treated group showed improvement in their haematological profile. Conclusion: Based on our findings, the use of penstrep in the management of PPR-infected goats gave a better result.

Reduced-complexity model for the impact of anthropogenic CO₂ emissions on future glacial cycles

We propose a reduced-complexity process-based model for the long-term evolution of the global ice volume, atmospheric CO2 concentration, and global mean temperature. The model's only external forcings are the orbital forcing and anthropogenic CO2 cumulative emissions. The model consists of a system of three coupled non-linear differential equations representing physical mechanisms relevant for the evolution of the climate–ice sheet–carbon cycle system on timescales longer than thousands of years. Model parameters are calibrated using paleoclimate reconstructions and the results of two Earth system models of intermediate complexity. For a range of parameters values, the model is successful in reproducing the glacial–interglacial cycles of the last 800 kyr, with the best correlation between modelled and global paleo-ice volume of 0.86. Using different model realisations, we produce an assessment of possible trajectories for the next 1 million years under natural and several fossil-fuel CO2 release scenarios. In the natural scenario, the model assigns high probability of occurrence of long interglacials in the periods between the present and 120 kyr after present and between 400 and 500 kyr after present. The next glacial inception is most likely to occur ∼50 kyr after present with full glacial conditions developing ∼90 kyr after present. The model shows that even already achieved cumulative CO2 anthropogenic emissions (500 Pg C) are capable of affecting the climate evolution for up to half a million years, indicating that the beginning of the next glaciation is highly unlikely in the next 120 kyr. High cumulative anthropogenic CO2 emissions (3000 Pg C or higher), which could potentially be achieved in the next 2 to 3 centuries if humanity does not curb the usage of fossil fuels, will most likely provoke Northern Hemisphere landmass ice-free conditions throughout the next half a million years, postponing the natural occurrence of the next glacial inception to 600 kyr after present or later.

Chronic wasting disease in Europe: new strains on the horizon

Prion diseases are fatal neurodegenerative disorders with known natural occurrence in humans and a few other mammalian species. The diseases are experimentally transmissible, and the agent is derived from the host-encoded cellular prion protein (PrPC), which is misfolded into a pathogenic conformer, designated PrPSc (scrapie). Aggregates of PrPSc molecules, constitute proteinaceous infectious particles, known as prions. Classical scrapie in sheep and goats and chronic wasting disease (CWD) in cervids are known to be infectious under natural conditions. In CWD, infected animals can shed prions via bodily excretions, allowing direct host-to-host transmission or indirectly via prion-contaminated environments. The robustness of prions means that transmission via the latter route can be highly successful and has meant that limiting the spread of CWD has proven difficult. In 2016, CWD was diagnosed for the first time in Europe, in reindeer (Rangifer tarandus) and European moose (Alces alces). Both were diagnosed in Norway, and, subsequently, more cases were detected in a semi-isolated wild reindeer population in the Nordfjella area, in which the first case was identified. This population was culled, and all reindeer (approximately 2400) were tested for CWD; 18 positive animals, in addition to the first diagnosed case, were found. After two years and around 25,900 negative tests from reindeer (about 6500 from wild and 19,400 from semi-domesticated) in Norway, a new case was diagnosed in a wild reindeer buck on Hardangervidda, south of the Nordfjella area, in 2020. Further cases of CWD were also identified in moose, with a total of eight in Norway, four in Sweden, and two cases in Finland. The mean age of these cases is 14.7 years, and the pathological features are different from North American CWD and from the Norwegian reindeer cases, resembling atypical prion diseases such as Nor98/atypical scrapie and H- and L-forms of BSE. In this review, these moose cases are referred to as atypical CWD. In addition, two cases were diagnosed in red deer (Cervus elaphus) in Norway. The emergence of CWD in Europe is a threat to European cervid populations, and, potentially, a food-safety challenge, calling for a swift, evidence-based response. Here, we review data on surveillance, epidemiology, and disease characteristics, including prion strain features of the newly identified European CWD agents.

Flood of Ecology - Floodplain Habitation

<p>Larger and more devastating flood events are happening more frequently across the planet, but flooding is a natural occurrence for any river system. It is only due to human modification of the river system, through the removal of natural features and attempts at flood control, that creates flood hazards that cause damage to communities and ecosystems. Kapiti Coast’s terrain consisted, pre 19th century, of a mixture of dense coastal forests and extensive wetlands. The landscape has and always will be prone to flooding. With the addition of the expressway to the region, making it easier to travel to and from the capital Wellington, it is expected that the population of Kapiti will grow. But biodiversity may get lost, and flooding may become increasingly more frequent. How might new settlers learn to live with flooding and the constant risk that every time it rains it may cause damage to their homes or businesses? Can there be other benefits to floodplain management, such as biodiversity and recreation? The aim of this research is to investigate and develop strategies to aid in the settlement of floodplains so that biodiversity is improved, allowing people to live with floods and without the fear that flooding may cause damage. Specifically, the design-led research seeks to generate solutions that improve both flood awareness and flood protection along the Waikanae River. The design seeks to allow the river to express its own flow patterns, and then secondly, how settlement will work within that. It can then be a catalyst for settlement of floodplain areas along the edge of the river. This thesis will explore how ecology, rehabilitation and natural flood protection can be employed amongst an expanding urban context to create a new way of thinking about our rivers and mitigating the ever pressing issue of flooding.</p>