Three Dimensional Reductions of Four-Dimensional Quasilinear Systems

In this paper we show that integrable four dimensional linearly degenerate equations of second order possess infinitely many three dimensional hydrodynamic reductions. Furthermore, they are equipped infinitely many conservation laws and higher commuting flows. We show that the dispersionless limits of nonlocal KdV and nonlocal NLS equations (the so-called Breaking Soliton equations introduced by O.I. Bogoyavlenski) are one and two component reductions (respectively) of one of these four dimensional linearly degenerate equations

An approach to the low-resistance measurement

The paper presents the real instrument functional characteristics and describes the way of practical solutions of its performance improvement. It presents the design process of the instrument made for resistance measuring. In order to achieve desired objectives, a great number of experiments have been carried out during the development. Basically, the comparison method has been applied. At first, it was intended for the small resistor measuring as a single range unit. Later, the device has been improved and upgraded for a wide range resistance measuring. Finally, some of the difficulties have been detected and explained as well. The paper contains solutions developed and applied for their overcoming. [Projekat Ministarstva nauke Republike Srbije, br. TR 33037 i br. TR 34005

Uticaj vlažnosti pri berbi na klijavost semena kukuruza

Modern maize seed drying and processing technology is applied today to ensure high quality grain. The most important factor in preserving seed quality is the moisture content. The time of harvesting, drying, storage and seed conservation is determined by the seed water quantity. At the harvesting time, a lower moisture content is desirable due to seed physiological maturity as well as consequences that may be caused during seed drying. During seed storage, water in seed is maintained at the level of latency to preserve vital seed functions, for maize it is 13-14 %. Influence of different seed moisture content, during harvesting time, on maize seed quality were studied in this research. Two physiological traits of seed were observed: seed energy and germination. Material used in this research were maize hybrids ZP 434 and ZP 666. Moisture content during harvesting time was measured after drying and primary processing, two seed sizes were obtained. From the divided seed samples were taken for laboratory tests. Harvesting was done at different seed moisture content lt 25 %, 25-30 %, 30-35 % and > 35 %. Maize cobs were dried in double-pass system drier with air temperature below 42 oC. Cob moisture is measured with moisture meter (Pfeuffer). Seed was divided into two fractions according to size using sieves with mesh sizes ranging from 6.5 - 8.3 mm and 8.4 - 11.0 mm. Seed energy and germination were determined in seed testing laboratory on working samples 4x100 seed, by standard maize germination test with ISTA Rules, and Rule on the quality of seed of agricultural plants. Experimental results were calculated on average mean and total variability (SD i C.V.) for seed energy, germination and moisture content. The three factorial analysis of variance was calculated for both germination traits (seed energy and germination), for factors: hybrid, seed sizes and seed moisture content. The results of all factors and traits had different values. The highest means of seed energy and germination in both fractions of both observed hybrids were recorded with the seed moisture content ranging from 30 to 35 %.U cilju dobijanja što kvalitetnijeg semenskog materijala, danas je u primeni savremena tehnologija dorade i sušenja semena. Jedan od osnovnih činilaca očuvanja kvaliteta semena je voda. Količina vode u semenu određuje vreme berbe, način sušenja, skladištenja i očuvanja kvaliteta semena.U vreme berbe poželjan je manji sadržaj vode, kako zbog fiziološke zrelosti semena tako i zbog posledica koje mogu biti uzrokovane dužim periodom sušenja. Za vreme čuvanja semena voda se održava na nivou latentnosti životnih funkcija, a za kukuruz to je 13-14%. U ovim istraživanjima posmatran je uticaj različitih vlažnosti semena u toku berbe na kvalitet semena. Posmatrane su dve fiziološke osobine semena: energija klijanja i klijavost. Materijal korišćen u istraživanjima su dva hibrida kukuruza ZP 434 i ZP 666. Berba je vršena sa različitom vlažnošću semena, a posle sušenja i krunjenja, iz naturalnog semenskog materijala izdvojene su dve frakcije po krupnoći. Iz podeljenog semenskog materijala izdvajani su uzorci za laboratorijsko ispitivanje semena. Berba je vršena sa različitom vlažnošću semena, koja je bila: lt 25%, 25-30%, 30-35% i sa vlažnošću većoj od 35%. Sušenje semenskog klipa obavljeno je u sušarama tipa komora sa dva prolaza fluida za sušenje klipa kukuruza na temperaturi ispod 42oC. Ulazna vlaga klipa merena je laboratorijskim uređajima za određivanje vlage Pfeuffer. Deljenje semena na dve frakcija izvršeno je po krupnoći korišćenjem sita promera 6,5-8,3 mm i 8,4-11,0 mm. Ispitivanje energije klijanja i klijavosti rađeno je u laboratoriji za ispitivanje semena na radnom uzorku 4x100 semena po standardnoj metodi na naizmeničnoj temperaturi 20-30oC po ISTA pravilima i Pravilniku o kvalitetu semena poljoprivrednog bilja. Eksperimentalni podaci obrađeni su na srednju vrednost, standardnu devijaciju i ukupnu varijabilnost (SD i C.V.) za sve osobine semena i svaku varijantu istraživanja. Trofaktorijalna analiza varijanse urađena je za obe posmatrane osobine semena (energiju klijanja i klijavost), za faktore: hibrid, frakcija i vlažnost semena. Dobijeni rezultati po svim osnovama, pokazuju različite vrednosti. Najveća enegija klijanja i klijavost semena utvrđeni su za seme čija je vlaga u toku berbe bila 30-35% za oba ispitivana hibrida

Metabolični sindrom i ishod u bolesnika s akutnim infarktom miokarda

The impact of the metabolic syndrome/insulin resistance syndrome (MS/IR S) on the severity and prognosis of acute ST elevation myocardial infarction (STEMI ) treated with primary percutaneous coronary intervention (PCI) was assessed using the American Association of Clinical Endocrinologists and American College of Endocrinology (AACE/ACE) definition from 2003. A total of 385 patients having suffered acute STEMI and treated with primary PCI over a two-year period were divided into two groups (with and without MS/IR S) and compared according to the parameters of severity (clinical, laboratory, echocardiography, coronary angiography parameters and complications) and prognosis using major adverse cardiovascular events (MACE) during the six-month follow-up of acute STEMI . In comparison with control group, the MS/IR S group of patients had worse or similar results of almost all study parameters of severity (hospital days 6.5 vs. 6.5, cardiogenic shock 2.9% vs. 2.6%, cardiac arrest 6.8% vs. 5.2%, reinfarction 0.5 vs. 1.6%) and prognosis (total MACE 30.7 vs. 30.7%), however, none of the differences reached statistical significance. It is concluded that the unexpected lack of such differences in MS/IR S could be due to the absence of waist-to-hip ratio in the definition and other open questions in metabolic syndrome in general.Istraživao se utjecaj metaboličnog sindroma/sindroma inzulinske rezistencije (MS/SIR ) koristeći definiciju American Association of Clinical Endocrinologists i American College of Endocrinology (AACE/ACE) iz 2003. na težinu i prognozu akutnog infarkta miokarda s elevacijom ST spojnice (STEMI ) liječenog primarnom perkutanom intervencijom (pPCI). Ukupno 395 bolesnika koji su preboljeli akutni STEMI i bili liječeni pomoću pPCI u dvogodišnjem razdoblju podijeljeno je u dvije skupine (s MS/SIR i bez njih) i uspoređeno prema parametrima težine (klinički, laboratorijski, ehokardiografski, koronarografski, komplikacije) i prognoze koristeći velike neželjene kardiovaskularne događaje (MACE) tijekom šestomjesečnog praćenja akutnog STEMI . Skupina bolesnika s MS/SIR u usporedbi s kontrolnom skupinom imala je uglavnom lošije ili jednake rezultate težine (dani u bolnici 6,5:6,5, kardiogeni šok 2,9%:2,6%, srčani zastoj 6,8%:5,2%, reinfarkt 0,5%:1,6%) i prognoze (ukupno MACE 30,7%:30,7%), no niti jedna od razlika nije dosegla statističku značajnost. Zaključuje se kako bi izostanak takvih očekivanih razlika u MS/SIR mogao biti posljedica isključenja omjera struka i kukova iz ove definicije i ostalih otvorenih pitanja u metaboličnom sindromu uopće

Influence of Passive Smoking on Basic Anthropometric Characteristics and Respiratory Function in Young Athletes

The primary objective of this study is to investigate the maintenance difference in basic anthropometric characteristics and to outline the dynamics of respiratory function change in youngsters athletes exposed to passive smoking (PS) and athletes not exposed to passive smoking in their families (NPS). High and weight were determined as basis anthropometric characteristics. Measured parameters for respiratory function were vital capacity (VC), forced expiratory volume in the first second (FEV1), maximum expiratory flow (PEF), forced expiratory flow at 50% forced vital capacity (MEF 50) and forced expiratory flow at 25% forced vital capacity (MEF 25). Significant statistical differences in separate spirometric variable were found in three variables (FEV1, MEF50, and MEF25) for group older youngsters. Analysis of variance showed statistical differences between athletes unexposed to passive smoking (NPS) and athletes exposed to passive smoking (PS) in even four spirometric variables (VC, FEV1, MEF50 and MEF25)