Description of a new diatom (Bacillariophyta) species—Craticula anatoliana sp. nov.—and the first ultrastructure characteristic for Craticula vixvisibilis var. distinctior

This paper presents the first scanning electron microscope documentation and valve ultrastructure description of the rare species Craticula vixvisibilis var. distinctior Lange-Bertalot, and a description of the new species Craticula anatoliana sp. nov. Both species occurred in high electrolyte content, brackish maar-type lakes in the Inner Anatolia region of Turkey. The most similar species to this newly described species is Craticula buderi (Hustedt) Lange-Bertalot, from which it can be easily distinguished based on valve outline and striae density. Additionally, comparisons of C. vixvisiblis var. distinctior to most morphologically similar species were given based on literature data.

Sweat Characteristics of Cramp-Prone and Cramp-Resistant Athletes

Exercise-associated muscle cramps (EAMCs) are thought to be caused by dehydration and/or electrolyte losses. In this multicenter, cross-sectional study, the authors determined whether sweat rates (SRs), sweat electrolyte concentrations, or sweat electrolyte content differed in athletes with (i.e., crampers) and without (i.e., noncrampers) a history of EAMCs and whether these variables could predict EAMC-prone athletes. Male and female collegiate athletes (N = 350) from 11 sports with (n = 245) and without (n = 105) a self-reported history of EAMCs completed a typical exercise or conditioning session. SRs, calculated from body mass, and posterior forearm sweat were analyzed for sweat sodium concentration ([Na+]sw), sweat potassium concentration ([K+]sw), and sweat chloride concentration ([Cl−]sw). The authors used SRs and sweat electrolyte concentrations to calculate sweat electrolyte content lost. Within each gender, no differences in SRs (204 males, p = .92; 146 females, p = .24); [Na+]sw (191 males, p = .55; 126 females, p = .55); Na+sw content (191 males, p = .59; 126 females, p = .20); [K+]sw (192 males, p = .57; 126 females, p = .87); K+sw content (192 males, p = .49; 126 females, p = .03); [Cl−]sw (192 males, p = .94; 77 females, p = .57); and Cl−sw content (192 males, p = .55; 77 females, p = .34) occurred between crampers and noncrampers. Receiver operating characteristic curve analysis revealed that sweat electrolyte content and SRs were predictive of EAMC-prone athletes in American football (area under curve = 0.65–0.72, p ≤ .005), but not in any other sport. EAMCs may not be solely caused by fluid or electrolyte losses in most athletes. Fluid and electrolyte replacement may help American footballers. Clinicians should individualize fluid and electrolyte replacement and understand different etiologies for EAMCs.

Characterization of electrolyte content in urine samples through a differential microfluidic sensor based on dumbbell-shaped defected ground structures

In this paper, a differential microfluidic sensor and comparator based on a pair of microstrip lines loaded with dumbbell-shaped defected ground structure resonators is applied to the characterization of electrolyte concentration in samples of horse urine. Since variations in the total electrolyte content in urine may be indicative of certain pathologies, the interest is to use the device as a comparator, in order to determine changes in the electrolyte concentration as compared to a reference level. To validate the approach, we have made differential measurements of a set of urine samples with different electrolyte concentrations (which have been previously obtained by means of electrochemical methods). The obtained results correlate with the nominal electrolyte concentrations of the samples, thereby pointing out the potential of the approach as a low-cost pre-screening method (or complementary diagnosis system) to detect potential pathologies or diseases in horses and other animals.

New records and the first SEM description of a rare diatom Cavinula lapidosa (Krasske) Lange-Bertalot (Bacillariophyta)

Cavinula lapidosa (Krasske) Lange-Bertalot is a rare species found in oligo- and mesotrophic waters with low electrolyte content, on swamps, wet rocks, mosses and bogs. The occurrence of C. lapidosa was recorded during an analysis of the diatom diversity in Poland. This species was found in the headwaters of Jamów stream and a tributary of River Wisłoka from 2007 to 2014. Cavinula lapidosa is a diatom considered "extinct" or "probably extinct" within the territory of Poland. The species develops mainly in the upper, shaded sections of streams, always as single cells among mosses growing on rocks and rarely on the rocks themselves. In 2018–2019 numerous population of this species was found on mosses overgrowing an old abandoned basement in the Wisłoka River basin area. In this study, the lectotype slide of Navicula lapidosa was examined using light microscopy, and based on the collected samples, the first SEM observations of the ultrastructure of the valves were made.

Diatoms of the genus Navicula from waterbodies of the Voronezh Region, Russia

The diversity of the genus Navicula including 29 species, one species new to science (Navicula trophicatrixoides Chudaev, sp. nov.), one new to the flora of Russia (N. alineae), and 15 species new for the Voronezh Region, is documented from waterbodies located in the museum-reserve “Divnogorye” and areas in its vicinity. It is supposed that N. antonii as currently understood represents a complex with at least two semicryptic species. The most frequent taxa in the studied materials are Navicula cf. antonii, N. capitatoradiata and N. cryptotenella. The majority of the species found prefer waters with higher electrolyte content.

Systems of two immiscible liquids for a new type of membraneless fuel cells using renewable fuel

Systems of two immiscible liquids are proposed for a new type of membraneless fuel cells using renewable fuel, in which the stationary phase boundary carries out a role of membrane. These systems consist of water, alcohol (preferable ethanol) and a number of electrolytes (salts and bases) leading to the layering of aqueous alcohol. In such systems top phase has significant alcohol content and insignificant electrolyte content, bottom phase has significant electrolyte content and insignificant alcohol content. To study the layering conditions in these systems, binodal curves were plotted for three two-phase liquid systems (EtOH + K2CO3 + H2O; EtOH + K3PO4 + H2O, EtOH + KOH + H2O), using the cloud point method. Comparison of our experimental data with the results of other authors showed that they are consistent for the first and second systems, and the temperature dependence of the binodal curves is clearly visible for the third system. The specific system EtOH – 30 % m/m; KOH – 40 % m/m; H2O – 30 % m/m was taken as the basis for studies of fuel cells based on two immiscible liquids. A further area of research lies in the field of optimizing the composition of both phases, studying the processes of mass transfer in these systems and their physicochemical characteristics.

Stabilization of Li–S batteries with a lean electrolyte via ion-exchange trapping of lithium polysulfides using a cationic, polybenzimidazolium binder

An active cationic polymer binder absorbs dissolved polysulfides for suppressing the shuttle effect and simultaneously forms a Li+ conducting phase, allowing Li–S cells to work at a lean electrolyte content.

Study of electromotive force of a new type of membraneless fuel cell operating on renewable fuel

The possibility of using base metals and alloys based on them as electrodes for a new type of membraneless fuel cells operating on renewable fuel has been investigated. The phase boundary of two immiscible liquids in the ethanol-water-potassium hydroxide system plays a role of a membrane in these elements. Top phase of this fuel cell has significant alcohol content and insignificant electrolyte content, bottom phase has significant electrolyte content and insignificant alcohol content. Platinum- and ruthenium-coated titanium electrode, carbon electrode and stainless steel electrode were used as the anode. Stainless steel electrode and carbon steel electrode were used as the cathode. The possibility of using ferrous alloys as anode and cathode catalysts in this type of fuel cells is shown.

Freshwater achnanthoid diatoms (Bacillariophyta) of the southern part of the Murmansk Region

During the investigation of achnanthoid diatoms in the southern part of the Murmansk Region 32 species belonging to 1 order, 1 family and 6 genera were found. The genera Psammothidium and Achnanthidium were represented by the largest number of species. Eleven species are new for the flora of the region. Most species are characteristic for oligotrophic waters with low to medium electrolyte content and neutral to weakly acidic pH. A new nomenclatural combination Achnanthidium nodosum comb. nov. is proposed.