Fitting Ranked English and Spanish Letter Frequency Distribution in U.S. and Mexican Presidential Speeches

The limited range in its abscissa of ranked letter frequency distributions causes multiple functions to fit the observed distribution reasonably well. In order to critically compare various functions, we apply the statistical model selections on ten functions, using the texts of U.S. and Mexican presidential speeches in the last 1-2 centuries. Dispite minor switching of ranking order of certain letters during the temporal evolution for both datasets, the letter usage is generally stable. The best fitting function, judged by either least-square-error or by AIC/BIC model selection, is the Cocho/Beta function. We also use a novel method to discover clusters of letters by their observed-over-expected frequency ratios.Comment: 7 figure

Key Amino Acid Residues of Ankyrin-Sensitive Phosphatidylethanolamine/Phosphatidylcholine-Lipid Binding Site of βI-Spectrin

It was shown previously that an ankyrin-sensitive, phosphatidylethanolamine/phosphatidylcholine (PE/PC) binding site maps to the N-terminal part of the ankyrin-binding domain of β-spectrin (ankBDn). Here we have identified the amino acid residues within this domain which are responsible for recognizing monolayers and bilayers composed of PE/PC mixtures. In vitro binding studies revealed that a quadruple mutant with substituted hydrophobic residues W1771, L1775, M1778 and W1779 not only failed to effectively bind PE/PC, but its residual PE/PC-binding activity was insensitive to inhibition with ankyrin. Structure prediction and analysis, supported by in vitro experiments, suggests that “opening” of the coiled-coil structure underlies the mechanism of this interaction. Experiments on red blood cells and HeLa cells supported the conclusions derived from the model and in vitro lipid-protein interaction results, and showed the potential physiological role of this binding. We postulate that direct interactions between spectrin ankBDn and PE-rich domains play an important role in stabilizing the structure of the spectrin-based membrane skeleton

Demographic and reproductive associations with nematode infection in a long-lived mammal

Infection by macroparasites, such as nematodes, varies within vertebrate host systems; elevated infection is commonly observed in juveniles and males, and, for females, with different reproductive states. However, while such patterns are widely recognized in short-lived model systems, how they apply to long-lived hosts is comparatively understudied. Here, we investigated how infection varies with host age, sex, and female reproduction in a semi-captive population of individually marked Asian elephants Elephas maximus. We carried out 1,977 faecal egg counts (FECs) across five years to estimate nematode loads for 324 hosts. Infection patterns followed an established age-infection curve, whereby calves (5 years) exhibited the highest FECs and adults (45 years) the lowest. However, males and females had similar FECs across their long lifespan, despite distinct differences in life-history strategy and clear sexual dimorphism. Additionally, although mothers invest two years in pregnancy and a further three to five years into lactation, nematode load did not vary with four different measures of female reproduction. Our results provide a much-needed insight into the host-parasite dynamics of a long-lived host; determining host-specific associations with infection in such systems is important for broadening our knowledge of parasite ecology and provides practical applications for wildlife medicine and management

Spectrin-based skeleton as an actor in cell signaling

This review focuses on the recent advances in functions of spectrins in non-erythroid cells. We discuss new data concerning the commonly known role of the spectrin-based skeleton in control of membrane organization, stability and shape, and tethering protein mosaics to the cellular motors and to all major filament systems. Particular effort has been undertaken to highlight recent advances linking spectrin to cell signaling phenomena and its participation in signal transduction pathways in many cell types

Fifth European Dirofilaria and Angiostrongylus Days (FiEDAD) 2016

Peer reviewe

Układ sterowania synchronizacją siłowników hydraulicznych z wykorzystaniem średniej arytmetycznej ich położeń

The aim of the control system is to ensure the effective synchronization of the cylinders motion and simultaneous minimization of volume loss in the throttling hydraulic systems. In the proposed control system, arithmetic mean of the synchronized cylinders displacements is the command value to the control subsystems where identical controllers are used. The number of the control subsystems is equal to the number of the synchronized cylinders. Developed control system enables effective motion synchronization of arbitrary number of the hydraulic cylinders with the pressure of the working liquid resulting from the current cylinders load.Celem układu sterowania jest zapewnienie efektywnej synchronizacji ruchu siłowników wraz z minimalizacją strukturalnych strat objętościowych, jakie występują w dławieniowych układach hydraulicznych. W proponowanym układzie sterowania, średnia arytmetyczna przemieszczeń synchronizowanych siłowników jest wartością zadaną do podsystemów sterowania, w których zastosowano identyczne regulatory. Liczba podsystemów sterowania jest równa liczbie synchronizowanych siłowników. Opracowany układ sterowania umożliwia efektywną synchronizację ruchu dowolnej liczby siłowników hydraulicznych przy ciśnieniu cieczy roboczej wynikającym z bieżącego obciążenia siłowników

Experimental investigation on the piezoelectric energy harvester as a self-powered vibration sensor

The article presents an experimental study of a system consisting of a piezoelectric energy harvesting device, Graetz bridge rectifier, capacitor, voltage comparator and radio transmitter. In the presented experimental study, the recovered electrical energy is accumulated in the capacitor and is used to send signals by a radio transmitter. In the first part, the application of piezoelectric energy harvesting devices based on the cantilever beam in wireless monitoring systems is discussed. In the second part, the mathematical model of energy conversion in the piezoelectric energy harvesting devices is presented. In the third part, the characteristics obtained during laboratory research are presented

Eksperymentalne badania nad pozyskiwaniem energii z drgań mechanicznych budynków z wykorzystaniem kompozytu macro fiber

The monitoring of a structure (e.g., a building) enables safe utilization of such a structure. A large number of sensors that measure selected parameters are often required in applied monitoring systems. Cables or batteries are used to power such sensors. This leads to an increase in utilization costs, as the cables have to be spatially located in a monitored building structure, or batteries have to be changed periodically. The use of the natural properties of piezoelectric materials that convert mechanical energy into electńcal energy in places where sensors are mounted is a promising field of wireless monitońng system development. This article presents the results of an experimental study for an energy harvesting system using a piezoelectric composite - the Macro Fiber Composite (MFC). The device used for energy harvesting has a beam structure that was achieved by gluing steel and MFC together. In laboratory research, the characteristics of generated currents and electńcal power were obtained for several values of vibration amplitude. The most important conclusion was that the resonant frequency of a piezoelectric beam generator should be established (by the selection of proper dimension or land mass) both for the vibration frequency of the monitored mechanical structure and the vibration amplitude of this structure.Monitorowanie stanu konstrukcji np. budowlanej pozwala na jej bezpieczną eksploatację. Często w stosowanych w tym celu systemach monitorowania wymagane jest zastosowanie znacznej liczby czujników, mierzących wybrane parametry. Do zasilania tych czujników stosuje się kable lub baterie, co prowadzi do większych kosztów eksploatacji konstrukcji budowlanej, gdyż w przypadku kabli muszą być one umieszczone w monitorowanej konstrukcji, a w przypadku baterii muszą być one wymieniane co pewien czas. Wykorzystanie właściwości materiałów piezoelektrycznych do konwersji energii mechanicznej na elektryczną w miejscach zamontowania czujników jest obiecującym kierunkiem rozwoju bezprzewodowych systemów monitoringu. W artykule przedstawiono wyniki badań eksperymentalnych układu pozyskiwania energii, w którym wykorzystano kompozyt piezoelektryczny Macro Fiber Composite (MFC). Urządzenie do pozyskiwania energii miało konstrukcję belkową otrzymaną przez sklejenie stali i MFC. W badaniach laboratoryjnych uzyskano charakterystyki generowanego natężenia prądu i mocy elektrycznej przy zmianach wartości amplitudy drgań. Na podstawie badań m.in. wykazano, że częstotliwość rezonansowa piezoelektrycznego generatora o konstrukcji belkowej powinna być ustalana (przez odpowiedni dobór wymiarów lub/i masy) zarówno na podstawie najczęściej występującej częstotliwości drgań monitorowanej konstrukcji mechanicznej, jak i na podstawie najczęściej występujących amplitud drgań tej konstrukcji