A Synchronized Two-Dimensional α-Ω Model of the Solar Dynamo.

We consider a conventional α-Ω-dynamo model with meridional circulation that exhibits typical features of the solar dynamo, including a Hale-cycle period of around 20 years and a reasonable shape of the butterfly diagram. With regard to recent ideas of a tidal synchronization of the solar cycle, we complement this model by an additional time-periodic α-term that is localized in the tachocline region. It is shown that amplitudes of some decimeters per second are sufficient for this α-term to become capable of entraining the underlying dynamo. We argue that such amplitudes of α may indeed be realistic, since velocities in the range of m s-1 are reachable, e.g., for tidally excited magneto-Rossby waves. Supplementary Information: The online version contains supplementary material available at 10.1007/s11207-023-02173-y.

Mode Conversion and Period Doubling in a Liquid Rubidium Alfvén-Wave Experiment with Coinciding Sound and Alfvén Speeds.

We report Alfvén-wave experiments with liquid rubidium at the Dresden High Magnetic Field Laboratory. Reaching up to 63 T, the pulsed magnetic field exceeds the critical value of 54 T at which the Alfvén speed coincides with the sound speed. At this threshold, we observe a period doubling of an applied 8 kHz cw excitation, which is consistent with the theoretical expectation of a parametric resonance between magnetosonic waves and Alfvén waves. Similar mode conversions are discussed as a possible mechanism for heating the solar corona.

Four-Frequency Solution in a Magnetohydrodynamic Couette Flow as a Consequence of Azimuthal Symmetry Breaking.

The occurrence of magnetohydrodynamic quasiperiodic flows with four fundamental frequencies in differentially rotating spherical geometry is understood in terms of a sequence of bifurcations breaking the azimuthal symmetry of the flow as the applied magnetic field strength is varied. These flows originate from unstable periodic and quasiperiodic states with broken equatorial symmetry, but having fourfold azimuthal symmetry. A posterior bifurcation gives rise to twofold symmetric quasiperiodic states, with three fundamental frequencies, and a further bifurcation to a four-frequency quasiperiodic state which has lost all the spatial symmetries. This bifurcation scenario may be favored when differential rotation is increased and periodic flows with m-fold azimuthal symmetry, m being a product of several prime numbers, emerge at sufficiently large magnetic field.

Analysis of 90 day operation of the GINGERINO gyroscope: publisher's note.

This publisher's note identifies a figure error in Appl. Opt.57, 5844 (2018)APOPAI0003-693510.1364/AO.57.005844.

Analysis of 90 day operation of the GINGERINO gyroscope.

Gyroscopes IN GEneral Relativity (GINGER) is a proposed experiment with the aim of measuring in a ground laboratory the gravitoelectric and gravitomagnetic effects foreseen by general relativity through an array of ring laser gyroscopes. GINGERINO is a square ring-laser prototype that has been built to investigate the level of noise inside the Gran Sasso underground laboratory. GINGERINO has shown the advantage of the underground location. Now it provides suitable data for geophysics and seismology. Since May 2017, it has continuously acquired data. The analysis of the first 90 days shows that the duty cycle is higher than 95%, and the quantum shot noise limit is of the order of 10-10(rad/s)/Hz. It is located in a seismically active area, and it recorded part of the central Italy earthquakes. Its high sensitivity in the frequency band of fraction of hertz makes it suitable for seismology studies. The main purpose of the present analysis is to investigate the long-term response of the apparatus. Simple and fast routines to suppress the disturbances coming from the laser have been developed. The Allan deviation of the raw data reaches some 10-6 after about 106 s of integration time, while the processed data show an improvement of 1 order of magnitude. Disturbances at the daily time scale are present in the processed data, and the expected signal induced by polar motion and solid Earth tides is covered by those disturbances.

Association between chewing dysfunctions and temporomandibular disorders: A systematic review.

Temporomandibular disorder (TMD) is an umbrella condition presenting several signs and symptoms including pain in the temporomandibular joint (TMJ) and masticatory muscles, articular noises, earache, headache, irregular or restricted jaw function, chewing difficulty, and limited mouth opening. Such TMD impairment may cause disorders during the chewing process. Therefore, the purpose of this systematic review was to assess chewing dysfunctions measured by sEMG, and their association with TMD. A combination and variation in the descriptors "temporomandibular joint disorders", "masticatory dysfunctions", and electromyography were used to perform the searches across databases. The databases chosen were: LILACS, PubMed, Science Direct, Scopus, and Web of Science. Additionally, grey literature was assessed using Google Scholar, ProQuest, and OpenGrey. Studies in adults that diagnosed TMD through the Research Diagnostic Criteria for Temporomandibular Disorders (RDC/TMD), Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) or Helkimo Protocol were selected. Furthermore, those studies should have evaluated chewing processes through surface electromyography (sEMG). Risk of bias of the included studies was assessed through the Meta-Analysis of Statistics Assessment and Review Instrument (MAStARI) tool. Eleven included studies shown significant results; however, they evaluated discrepant parameters, presented high inconsistency in the application, and had chosen different tasks to analyse the sEMG and hence, there was no consensus in the results of studies. In conclusion, strength of recommendations was very low due to a series of limitations on studies and it was not possible to made categorical statement about association between TMD and chewing dysfunctions in adults when parameters of sEMG were analysed.

Linking dissipation-induced instabilities with nonmodal growth: The case of helical magnetorotational instability.

The helical magnetorotational instability is known to work for resistive rotational flows with comparably steep negative or extremely steep positive shear. The corresponding lower and upper Liu limits of the shear are continuously connected when some axial electrical current is allowed to flow through the rotating fluid. Using a local approximation we demonstrate that the magnetohydrodynamic behavior of this dissipation-induced instability is intimately connected with the nonmodal growth and the pseudospectrum of the underlying purely hydrodynamic problem.

A clock network for geodesy and fundamental science.

Leveraging the unrivalled performance of optical clocks as key tools for geo-science, for astronomy and for fundamental physics beyond the standard model requires comparing the frequency of distant optical clocks faithfully. Here, we report on the comparison and agreement of two strontium optical clocks at an uncertainty of 5 × 10(-17) via a newly established phase-coherent frequency link connecting Paris and Braunschweig using 1,415 km of telecom fibre. The remote comparison is limited only by the instability and uncertainty of the strontium lattice clocks themselves, with negligible contributions from the optical frequency transfer. A fractional precision of 3 × 10(-17) is reached after only 1,000 s averaging time, which is already 10 times better and more than four orders of magnitude faster than any previous long-distance clock comparison. The capability of performing high resolution international clock comparisons paves the way for a redefinition of the unit of time and an all-optical dissemination of the SI-second.

Real-time measurement of Plasmodium falciparum-infected erythrocyte cytoadhesion with a quartz crystal microbalance.

BACKGROUND: An important virulence mechanism of the malaria parasite Plasmodium falciparum is cytoadhesion, the binding of infected erythrocytes to endothelial cells in the second half of asexual blood stage development. Conventional methods to investigate adhesion of infected erythrocytes are mostly performed under static conditions, many are based on manual or semi-automated read-outs and are, therefore, difficult to standardize. Quartz crystal microbalances (QCM) are sensitive to nanogram-scale changes in mass and biomechanical properties and are increasingly used in biomedical research. Here, the ability of QCM is explored to measure binding of P. falciparum-infected erythrocytes to two receptors: CD36 and chondroitin sulfate A (CSA) under flow conditions. METHODS: Binding of late stage P. falciparum parasites is measured in comparison to uninfected erythrocytes to CD36- and CSA-coated quartzes by QCM observing frequency shifts. CD36-expressing cell membrane fragments and CSA polysaccharide were coated via poly-L-lysine to the quartz. The method was validated by microscopic counting of attached parasites and of erythrocytes to the coated quartzes. RESULTS: Frequency shifts indicating binding of infected erythrocytes could be observed for both receptors CD36 and CSA. The frequency shifts seen for infected and uninfected erythrocytes were strongly correlated to the microscopically counted numbers of attached cells. CONCLUSIONS: In this proof-of-concept experiment it is shown that QCM is a promising tool to measure binding kinetics and specificity of ligand-receptor interactions using viable, parasite-infected erythrocytes. The method can improve the understanding of the virulence of P. falciparum and might be used to cross-validate other methods.

Evolutionary ecotoxicology of perfluoralkyl substances (PFASs) inferred from multigenerational exposure: a case study with Chironomus riparius (Diptera, Chironomidae).

A multigeneration toxicity test on Chironomus riparius was performed with the aim of investigating the evolutionary consequences of exposure to perfluoralkyl substances (perfluorooctane sulfonic acid, PFOS; perfluorooctanoic acid, PFOA; perfluorobutane sulfonate, PFBS). Six-hundred larvae were bred per treatment and per generation until emergence and egg deposition under a nominal concentration of 10µg/L of contaminants. Newborn larvae were used to start the next generation. Evolution of genetic variability was evaluated along a total of 10 consecutive generations based on 5 microsatellite loci. Analysis of life-history traits (survival, sex ratio and reproduction) was also carried out. Rapid genetic variability reduction was observed in all treatments, including controls, across generations due to the test conditions. Nevertheless, an increased mutation rate determined a stronger conservation of genetic variability in PFOS and, at minor extent, in PFBS exposed populations compared to controls. No significant effects were induced by exposure to PFOA. Direct mutagenicity or induced stress conditions may be at the base of increased mutation rate, indicating the potential risk of mutational load caused by exposure to PFOS and PFBS. The test provided the opportunity to evaluate the use of approximate Bayesian computation (ABC) and coalescent approaches in evolutionary ecotoxicology. A weak performance was evidenced for ABC, either in terms of bias or dispersion of effective population sizes and of estimates of mutation rate. On the contrary, coalescent simulations proved the sensitivity of traditional genetic endpoints (i.e. heterozygosity and number of alleles) to the alteration of mutation rate, but not to erosion of genetic effective size.

Burn resuscitation on the African continent.

A survey of members of the International Society of Burn Injuries (ISBI) and the American Burn Association (ABA) indicated that although there was difference in burn resuscitation protocols, they all fulfilled their functions. This study presents the findings of the same survey replicated in Africa, the only continent not included in the original survey. One hundred and eight responses were received. The mean annual number of admissions per unit was ninety-eight. Fluid resuscitation was usually initiated with total body surface area burns of either more than ten or more than fifteen percent. Twenty-six respondents made use of enteral resuscitation. The preferred resuscitation formula was the Parkland formula, and Ringer's Lactate was the favoured intravenous fluid. Despite satisfaction with the formula, many respondents believed that patients received volumes that differed from that predicted. Urine output was the principle guide to adequate resuscitation, with only twenty-one using the evolving clinical picture and thirty using invasive monitoring methods. Only fifty-one respondents replied to the question relating to the method of adjusting resuscitation. While colloids are not available in many parts of the African continent on account of cost, one might infer than African burn surgeons make better use of enteral resuscitation.

Controlled nanometric phase transitions of phospholipid membranes by plasmonic heating of single gold nanoparticles.

The development of remotely controlled nanoscopic sources of heat is essential for investigating and manipulating temperature sensitive processes at the nanoscale. Here, we use single gold nanoparticles to rapidly deposit controlled amounts of heat in nanoscopic regions of defined size. This allows us to induce and control nanoscale reversible gel-fluid phase transitions in phospholipid membranes. We exploit the optical control over the phase transition to determine the velocity of the fluid phase front into the gel phase membrane and to guide the nanoparticles to specific locations. These results illustrate how single gold nanoparticles enable local thermodynamic investigation and manipulation on nanoscale (bio-) systems.

Effects of ultraviolet radiation on human cutaneous nerve fibres.

UNLABELLED: Due to an increasing number of skin diseases as a result of exposure to ultraviolet (UV) radiation, it is necessary to evaluate the effectiveness of new skin care formulations with broad-spectrum sunscreens. OBJECTIVES: This study aims to assess the status of nerve fibres in healthy human skin, to quantify effects of UV radiation on nerve endings, and to evaluate neuroprotective effects of new skin care formulations against UV exposure damage. METHODS: Samples were obtained from 34 female patients enrolled for plastic surgery and were immediately treated (10 min) with three emulsions: Cream 1, Cream 2 (placebo) and a sunscreen with sun protection factor 15 (SPF15). Control samples and those treated with the cream emulsions were exposed to UVA and UVB for 60 min. Nerve fibres were identified by immunofluorescence using a monoclonal antibody (anti-human CD56/NCAM). Cell damage was assessed by image analysis. RESULTS: Several cellular nervous structures were identified in the skin samples, including free nerve endings. UVA and UVB significantly decreased (40-60%) density of nerve endings in the control samples and those treated with placebo (Cream 2) or SPF15 (all P < 0.001). Cream 1 completely blocked effects of UV radiation on nerve endings (P > 0.05 vs. control). CONCLUSIONS: Quantification of cell damage induced by UV radiation provides useful information for identification of new skin care compounds with neuroprotective properties.

Leeches on mudskippers: host-parasite interaction at the water's edge.

A host-parasite relationship was observed, for the first time, between a piscicolid leech and a species of amphibious goby (Scartelaos tenuis) from an intertidal mud flat in southern Iran. Morphological and molecular investigations assign the leech to Zeylanicobdella arugamensis. Of the 3 endemic and sympatric mudskipper species living in the Persian Gulf (S. tenuis, Boleophthalmus dussumieri, and Periophthalmus waltoni), leeches were only found on S. tenuis (prevalence and mean intensity = 71.4% and 2.3 +/- 2.5, respectively), which is also the most-aquatic mudskipper species. Scartelaos tenuis is not the largest species, but more leeches (> or =4 leeches/host) were found on larger specimens (>12 cm standard length [SL]). Nonetheless, in aquaria, leeches also attached on P. waltoni. This suggests either an ecological partitioning of host-parasite complexes, determined by host habitat selection, or leech limited-resistance to air exposure, or both.

Spatial and seasonal variations in the water quality of the Amu Darya River (Central Asia).

Although the use of the water resources in Uzbekistan is strongly limited by their quality, it has to be noted that there is a lack of information and data within the international scientific literature with regard to the water chemical characteristics of the Amu Darya River, one of the main water resources in Central Asia. To add to such knowledge, this paper examines the spatial and temporal variation of the water quality of the Amu Darya River in order to assess its degree of degradation and the main causal factors. The functional relationships of the pollutants with respect to the flow regime are investigated. Finally an "opportune temporal window" for water withdrawal for filling the reservoirs, in relation to human consumption, will be indicated. The high salinization levels of the waters are mainly due to the presence of sulphates and chlorine. At the up-stream site salinity, although presenting elevated concentrations, does not exceed palatability levels; after the 450 km point the opportune temporal window for water withdrawal with acceptable salinity values is reduced to the period from May to September. Two main driving forces govern the temporal variation of the salinity of the Amu Darya water: a low drainage density of the area which limits the salt loads induced by the natural runoff processes, and snow and glacier melting in the upper catchment area which promotes dilution of the dissolved salts during the high-flow period. During low-flow periods salinity is strongly influenced by the return of waters used for land washing and irrigation.

Morphometric discriminant analysis for the classification of Diplectanum (Monogenea: monopisthocotylea), parasites of Sphyraena flavicauda.

The authors have examined the morphology of Diplectanum cazauxi and Diplectanum bauchotae through the observation of 23 specimens (10 of D. cazauxi and 13 of D. bauchotae) found during May 2003 on the gills of 2 specimens of Sphyraena flavicauda Rüppell, 1838 collected at Ras Mohammed National Park, Egypt. A discriminant analysis was performed on the morphometric data of opisthaptor to determine which parameters more accurately distinguish the two species. The best discriminant parameters resulted to be the copulatory apparatus and the central bar, which determined the absence of misclassification in the model. The discriminant functions are reported for the two species.

Surface-plasmon-mediated single-molecule fluorescence through a thin metallic film.

We demonstrate that fluorescence of single molecules in the nanometric vicinity of a thin gold film can be effectively excited and detected through the film with an epi-illumination scanning confocal microscope. A full theoretical treatment of the fluorescence signal indicates that both excitation and emission are surface-plasmon mediated. Remarkably, the number of photons detectable from chromophores perpendicular to the interface is enhanced by the presence of the metal.

[Anthrax--an old disease becomes topical: cutaneous anthrax and the eye]. / Anthrax--altbekannt und hochaktuell Hautmilzbrand am Auge.

BACKGROUND: Anthrax disease and its eye manifestations were rare in the last 100 years, but the threat of terrorist actions has revived its topicality. MATERIALS AND METHODS: After an introductory historical review, the pathogenesis of this disease with regard to the virulence of Bacillus anthracis is reported. On the basis of photos displaying the course of the disease, the symptoms particularly of the cutaneous form of this disease as well as the diagnostic possibilities are described. RESULTS AND CONCLUSIONS: The current status of therapy and research for more effective treatment is discussed, with particular emphasis on the development of new substances with antitoxin properties and better vaccines. Bacillus anthracis is once again an actual threat, and therefore it is necessary for doctors to familiarize themselves with the current knowledge of this infection.

New records of alien monogeneans from Lepomis gibbosus and Silurus glanis in Italy.

The first geographical records of five alien monogeneans for Italy is reported. Four species have been detected from Lepomis gibbosus (Linnaeus, 1758): Actinocleidus recurvatus Mizelle et Donahue, 1944, Actinocleidus oculatus (Mueller, 1934), Urocleidus similis (Mueller, 1936) and Urocleidus dispar (Mueller, 1936); one species from Silurus glanis Linnaeus, 1758: Thaparocleidus vistulensis (Siwak, 1932) n. comb.

Description of three new polymorphisms in the intronic and 3'UTR regions of the human interferon gamma gene.

Interferon-gamma (IFN-gamma) is a key regulator of the development and functions of the immune system. In particular, this cytokine plays a major role in immune defense against infections by various human pathogens and polymorphisms in the IFN-gamma gene, including the transcription regulatory region, and might affect host resistance to infectious agents such as schistosomes. In this study on the genetics of human schistosomiasis we uncovered three new single nucleotide polymorphisms in the IFN-gamma genes. Two polymorphisms are located in the third intron and the third is in the 3'UTR region of this gene: an A to G transition at position +2109 from the transcription start and two G to A transitions at positions +3810 and +5134. In a SUDANESE population living in an endemic area of malaria and schistosomiasis, the allelic frequenciesare: 0.85 (+2109A), 0.15 (+2109G), 0.92 (+3810G), 0.08 (+3810A), (+5134G) and 0.04 (+5134A).