Mode Bifurcation and Fold Points of Complex Dispersion Curves for the Metamaterial Goubau Line

In this paper the complex dispersion curves of the four lowest-order transverse magnetic modes of a dielectric Goubau line ($\epsilon>0, \mu>0$) are compared with those of a dispersive metamaterial Goubau line. The vastly different dispersion curve structure for the metamaterial Goubau line is characterized by unusual features such as mode bifurcation, complex fold points, both proper and improper complex modes, and merging of complex and real modes

Endemic nephropathy

Autori iznose podatke o rezultatima dosadašnjih ispitivanja endemske nefropatije („nefropatije balkanskih zemalja“) jugoslavenskih, bugarskih, rumunjskih i drugih istraživača. Osvrću se na historijat, geografsku rasprostranjenost, učestalost i ističu epidemiološke značajke ove endemske bolesti. Razmatraju etiološke hipoteze, analizirajući potanje suvremene postavke o mogućim etiološkim faktorima. Navode obdukcijske i bioptičke pato-morfološke nalaze, ističući nađene razlike između nalaza pojedinih skupina istraživača. Osvrću se na kliničku sliku, teškoće u dijagnostici i dosadašnje rezultate u razradi i provjeri dijagnostičkih metoda koje doprinose dijagnozi dokazivanjem tubularnog tipa proteinurije. Kritički razmatraju pojedine rezultate i postavke, iznoseći svoje stavove koji rezultiraju iz vlastitih iskustava. U zaključku ističu socijalno-medicinske aspekte problema endemske nefropatije i zalažu se za potrebu intenzivnijeg planskog, usklađenog rada na istraživanju, koje bi omogućilo djelotvorne preventivne mjere.The results of studies of endemic nephropathy (Balkan Nephropathy) obtained by Yugoslav, Bulgarian, Roumanian and other authors are reviewed. The history of the disease, its geographical distribution and frequency are dealt with and epidemiological significance pointed out. Hypotheses concerning the etiology of the disease are considered and current assumptions about possible etiological factors are analyzed in detail. Pathological findings obtained by autopsy and biopsy are presented and differences in findings of various groups of authors discussed. The clinical picture of the disease, difficulties encountered in diagnosis and current results in the development and checking up of diagnostic methods for the detection of the tubular type of proteinuria are also described. Certain results and assumptions arc critically evaluated and commented upon from the point of view of own experience. In conclusion, socio-medical aspects of the problem of endemic nephropathy are presented and the necessity for intense, well planned and coordinated research which would result in efficient preventive measures is emphasized

Time-Varying Wireless Power Transfer Systems for Improving Efficiency

Conventional wireless power transfer systems are linear and time-invariant, which sets fundamental limitations on their performance, including a tradeoff between transfer efficiency and the level of transferred power. In this paper, we introduce and study a possibility of temporal modulation for inductive wireless power transfer systems and uncover that this tradeoff is avoided as a consequence of varying the inductive coupling strength in time. Our theoretical analysis reveals that under the optimal modulation depth and phase, the time modulation can yield a substantial improvement in the WPT efficiency, while the received power at the load is also improved compared to the static WPT reference system. We experimentally demonstrate the concept with a low-frequency system and observe a threefold improvement in efficiency over the reference static counterpart. This technical capability reconciles the inherent tradeoff between the WPT efficiency and transferred power, paving the way for simultaneous advancements in both efficiency and delivered power

Morbidity and mortality from endemic nephropathy in the village of Kaniža

Izneseni su rezultati jednogodišnjeg kontinuiranog kliničko-laboratorijskog praćenja populacije jednog endemskog sela u Brodskoj Posavini. Primijenjen način rada omogućuje egzaktnije određivanje stope morbiditeta a posebice mortaliteta. Tako je utvrđeno da je u selu Kaniži u toku 1974. godine od endemske nefropatije bolovala 7,3% ljudi, da je 4,3% sumnjivo na endemsku nefropatiju i da je 1,4% umrlo od tog uzroka. U dobnim skupinama starijih od 40 godina broj oboljelih raste geometrijskom progresijom. Žene obolijevaju nešto češće od muškaraca. Nema značajnih razlika u obolijevanju između autohtonog stanovništva i imigranata.A one-year study of endemic nephropathy was carried out in the village of Kaniža in the Posavina region near Slavonski Brod. The methods used in the study and the results obtained are presented in this paper. The study included the entire population of the selected village at risk. Four criteria important for the setting up of an accurate diagnosis were used: proteinuria, ereatinemia anemia and family history of endemic nephropathy. The most important criterion - proteinuria was determined by two methods: the sulphsalicylic test and an immunodiffusion test for beta, - microglobulins. These tests were performed once a month throughout the observation time (12 months). This allowed a safer distinction between real, pathognomonic and occasional or accidental albuminurias. To obtain as exact a mortality rate as possible the cause of each death was medically scrutinized, which is not an ordinary practice. In 1974 7.3% of the Kaniža population was affected by endemic nephropathy and 4.3% was found suspect. These percentages are inversely proportional to those recorded in previous observations. The number of cases in the age group of above 40 rises at a nearly geometric progression. Endemic nephropathy was the cause of death in 1.4% of the population which is a several times higher percentage than usually reported. Women are affected more often than men (8.5% and 6.0% respectively). This is in agreement with previous observations. At first sight the autochtonous population appears to be more susceptible to endemic nephropathy than immigrants (8.3% against 5.8%). However, if the autochtonous population aged over 20 is compared with immigrants who lived at Kaniža for over 20 years - this being an approximate minimal length of exposure to the hypothetical causative agents or the latent phase of the disease - there is in fact no difference (12% against 14%)

Temporal Processing of Vibratory Communication Signals at the Level of Ascending Interneurons in Nezara viridula (Hemiptera: Pentatomidae)

During mating, males and females of N. viridula (Heteroptera: Pentatomidae) produce sex- and species-specific calling and courtship substrate-borne vibratory signals, grouped into songs. Recognition and localization of these signals are fundamental for successful mating. The recognition is mainly based on the temporal pattern, i.e. the amplitude modulation, while the frequency spectrum of the signals usually only plays a minor role. We examined the temporal selectivity for vibratory signals in four types of ascending vibratory interneurons in N. viridula. Using intracellular recording and labelling technique, we analyzed the neurons' responses to 30 pulse duration/interval duration (PD/ID) combinations. Two response arrays were created for each neuron type, showing the intensity of the responses either as time-averaged spike counts or as peak instantaneous spike rates. The mean spike rate response arrays showed preference of the neurons for short PDs (below 600 ms) and no selectivity towards interval duration; while the peak spike rate response arrays exhibited either short PD/long ID selectivity or no selectivity at all. The long PD/short ID combinations elicited the weakest responses in all neurons tested. No response arrays showed the receiver preference for either constant period or duty cycle. The vibratory song pattern selectivity matched the PD of N. viridula male vibratory signals, thus pointing to temporal filtering for the conspecific vibratory signals already at level of the ascending interneurons. In some neurons the responses elicited by the vibratory stimuli were followed by distinct, regular oscillations of the membrane potential. The distance between the oscillation peaks matched the temporal structure of the male calling song, indicating a possible resonance based mechanism for signal recognition

The Ginninderra CH4 and CO2 release experiment: An evaluation of gas detection and quantification techniques

A methane (CH4) and carbon dioxide (CO2) release experiment was held from April to June 2015 at the Ginninderra Controlled Release Facility in Canberra, Australia. The experiment provided an opportunity to compare different emission quantification techniques against a simulated CH4 and CO2 point source release, where the actual release rates were unknown to the participants. Eight quantification techniques were assessed: three tracer ratio techniques (two mobile); backwards Lagrangian stochastic modelling; forwards Lagrangian stochastic modelling; Lagrangian stochastic (LS) footprint modelling; atmospheric tomography using point and using integrated line sensors. The majority of CH4 estimates were within 20% of the actual CH4 release rate (5.8 g/min), with the tracer ratio technique providing the closest estimate to both the CH4 and CO2 release rates (100 g/min). Once the release rate was known, the majority of revised estimates were within 10% of the actual release rate. The study illustrates the power of measuring the emission rate using multiple simultaneous methods and obtaining an ensemble median or mean. An ensemble approach to estimating the CH4 emission rate proved successful with the ensemble median estimate within 16% for the actual release rate for the blind release experiment and within 2% once the release rate was known. The release also provided an opportunity to assess the effectiveness of stationary and mobile ground and aerial CH4 detection technologies. Sensor detection limits and sampling rates were found to be significant limitations for CH4 and CO2 detection. A hyperspectral imager’s capacity to image the CH4 release from 100 m, and a Boreal CH4 laser sensor’s ability to track moving targets suggest the future possibility to map gas plumes using a single laser and mobile aerial reflector

The Ginninderra CH4 and CO2 release experiment: An evaluation of gas detection and quantification techniques

A methane (CH4) and carbon dioxide (CO2) release experiment was held from April to June 2015 at the Ginninderra Controlled Release Facility in Canberra, Australia. The experiment provided an opportunity to compare different emission quantification techniques against a simulated CH4 and CO2 point source release, where the actual release rates were unknown to the participants. Eight quantification techniques were assessed: three tracer ratio techniques (two mobile); backwards Lagrangian stochastic modelling; forwards Lagrangian stochastic modelling; Lagrangian stochastic (LS) footprint modelling; atmospheric tomography using point and using integrated line sensors. The majority of CH4 estimates were within 20% of the actual CH4 release rate (5.8 g/min), with the tracer ratio technique providing the closest estimate to both the CH4 and CO2 release rates (100 g/min). Once the release rate was known, the majority of revised estimates were within 10% of the actual release rate. The study illustrates the power of measuring the emission rate using multiple simultaneous methods and obtaining an ensemble median or mean. An ensemble approach to estimating the CH4 emission rate proved successful with the ensemble median estimate within 16% for the actual release rate for the blind release experiment and within 2% once the release rate was known. The release also provided an opportunity to assess the effectiveness of stationary and mobile ground and aerial CH4 detection technologies. Sensor detection limits and sampling rates were found to be significant limitations for CH4 and CO2 detection. A hyperspectral imager\u27s capacity to image the CH4 release from 100 m, and a Boreal CH4 laser sensor\u27s ability to track moving targets suggest the future possibility to map gas plumes using a single laser and mobile aerial reflector