Electrochemistry in pyridine-IV. Chemical and electrochemical reduction of pyridine

The cathodic polarographic wave observed for solutions of AlCl3 in pyridine is due not to reduction of Al(III), but to reduction of the solvent, in which process Al(III) plays an essential role, apparently by polarizing the pyridine through the formation of a Lewis acid-base adduct with the pyridine nitrogen. Macroscale electrolysis of pyridine solutions of AlCl3 at a mercury cathode results in the reduction of pyridine and the formation, after hydrolysis and air oxidation, of a complex mixture or copolymer of unsaturated polyamines and polyamides probably containing such units (moities) as: (-. CH:CH . CH2 . NH . CH--)[chi], and (-CH2 . CH2 . CH:CH . CO . NH--)[chi]. Essentially the same product is obtained by treatment of pyridine with LiAlH4. The reaction mechanisms proposed involve disruption of a C---N bond in pyridine.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/31984/1/0000026.pd

A review on the eco-epidemiology and clinical management of human granulocytic anaplasmosis and its agent in Europe

Anaplasma phagocytophilum is the agent of tick-borne fever, equine, canine and human granulocytic anaplasmosis. The common route of A. phagocytophilum transmission is through a tick bite, the main vector in Europe being Ixodes ricinus. Despite the apparently ubiquitous presence of the pathogen A. phagocytophilum in ticks and various wild and domestic animals from Europe, up to date published clinical cases of human granulocytic anaplasmosis (HGA) remain rare compared to the worldwide status. It is unclear if this reflects the epidemiological dynamics of the human infection in Europe or if the disease is underdiagnosed or underreported. Epidemiologic studies in Europe have suggested an increased occupational risk of infection for forestry workers, hunters, veterinarians, and farmers with a tick-bite history and living in endemic areas. Although the overall genetic diversity of A. phagocytophilum in Europe is higher than in the USA, the strains responsible for the human infections are related on both continents. However, the study of the genetic variability and assessment of the difference of pathogenicity and infectivity between strains to various hosts has been insufficiently explored to date. Most of the European HGA cases presented as a mild infection, common clinical signs being pyrexia, headache, myalgia and arthralgia. The diagnosis of HGA in the USA was recommended to be based on clinical signs and the patient’s history and later confirmed using specialized laboratory tests. However, in Europe since the majority of cases are presenting as mild infection, laboratory tests may be performed before the treatment in order to avoid antibiotic overuse. The drug of choice for HGA is doxycycline and because of potential for serious complication the treatment should be instituted on clinical suspicion alone

Exposure and risk factors to Coxiella burnetii, spotted fever group and typhus group rickettsiae, and Bartonella henselae among volunteer blood donors in Namibia

Background: The role of pathogen-mediated febrile illness in sub-Saharan Africa is receiving more attention, especially in Southern Africa where four countries (including Namibia) are actively working to eliminate malaria. With a high concentration of livestock and high rates of companion animal ownership, the influence of zoonotic bacterial diseases as causes of febrile illness in Namibia remains unknown.Methodology/Principal Findings: The aim of the study was to evaluate exposure to Coxiella burnetii, spotted fever and typhus group rickettsiae, and Bartonella henselae using IFA and ELISA (IgG) in serum collected from 319 volunteer blood donors identified by the Blood Transfusion Service of Namibia (NAMBTS). Serum samples were linked to a basic questionnaire to identify possible risk factors. The majority of the participants (64.8%) had extensive exposure to rural areas or farms. Results indicated a C. burnetii prevalence of 26.1% (screening titre 1:16), and prevalence rates of 11.9% and 14.9% (screening titre 1:100) for spotted fever group and typhus group rickettsiae, respectively. There was a significant spatial association between C. burnetii exposure and place of residence in southern Namibia (P0.012), especially cattle (P>0.006), were also significantly associated with C. burnetii exposure. Males were significantly more likely than females to have been exposed to spotted fever (P<0.013) and typhus (P<0.011) group rickettsiae. Three (2.9%) samples were positive for B. henselae possibly indicating low levels of exposure to a pathogen never reported in Namibia.Conclusions/Significance: These results indicate that Namibians are exposed to pathogenic fever-causing bacteria, most of which have flea or tick vectors/reservoirs. The epidemiology of febrile illnesses in Namibia needs further evaluation in order to develop comprehensive local diagnostic and treatment algorithms.Peer reviewedEntomology and Plant Patholog

Make use of multicriterion optymization tasks results in the designing low energy buildings

W pracy przedstawiono wyniki rozwiązania problemu optymalnego kształtowania budynków jednorodzinnych sformułowanego jako zadanie optymalizacji dwukryterialnej i wielopoziomowej. Przyjęte kryteria to minimum kosztu przegród zewnętrznych i minimum sezonowego zapotrzebowania na energię do ogrzewania. Zmieniając wartości dolnych ograniczeń dla izolacyjności ścian, oraz górnych ograniczeń dla wielkości współczynnika przeszklenia ściany południowej wyznaczono przekrój rozwiązań optymalnych, uzyskując w konsekwencji zbiór danych dla projektowania budynków o założonym przez projektanta zapotrzebowaniu na energie do ogrzewania.Optimization tasks were formulated (and worked) as a problems in designing low-energy apartment buildings. It is multi-criteria (minimum costs and minimum energy consumption) and multi-level optimization problems

Glass facades in energy-saving buildings

Zmiany uregulowań prawnych oraz moda na energooszczędność wymuszają na nowoczesnym budownictwie rozwój nowych materiałów i technologii. Fasady budynków, które do niedawna miały spełniać głównie funkcje reprezentatywne także muszą zostać dostosowane do tego trendu. Celem artykułu jest przegląd nowoczesnych systemów przeszkleń fasad budynków. Przedstawiono wymagania jakie muszą spełniać fasady szklane, aby mogły być uznane za niskoenergetyczne. Zaprezentowano także możliwości pozyskiwania energii słonecznej w nowoczesnych systemach fasad i okien.Changes in regulations and fashion for energy efficiency forces on modern building development of new materials and technology. Facades of buildings, which until recently have mainly representative functions, have to adapt to this trend. The purpose of this article is to review modern glazing facades systems of buildings. The requirements which must be fulfilled by glass facades to be considered for low energy were presented. There are also presented capabilities of obtaining solar energy in modern facades and windows