Oksidacijsko-antioksidacijski procesi i toplinski učinci na oksidativni stres u gmazova

Temperature is the most important abiotic factor and has a direct influence on the physiology of the organism, affecting nearly all other parameters of the living environment of organisms. Ectothermic organisms are highly endangered in the current crisis climate, as they are unable to use metabolic heat to maintain body temperature. Reptiles are ectothermic vertebrates that are also susceptible to temperature fluctuations. Metabolism, muscle and nervous system function and reproduction are closely linked to reptile body temperature. To study the effects of temperature on oxidative stress, it is necessary to describe the generation of reactive oxygen species (ROS) and how organisms can prevent oxidative stress. This article describes the oxidation-antioxidation processes and the oxidative stress caused by thermal effects in reptiles. In the metabolic processes of aerobic organisms, ROS are continuously generated as by-products of oxidation-reduction reactions and are not primarily harmful. Furthermore, ROS are essential for many physiological functions, e.g., for energy production and for processes in the immune system. The potential toxicity of reactive oxygen radicals under physiological conditions is prevented by the antioxidant defence system. Oxidative stress occurs when the balance between oxidation and antioxidation systems is disturbed by excessive amounts of ROS or by the depletion of antioxidants. It is known that the metabolic rate of reptiles correlates with environmental temperature, making them physiologically more sensitive to temperature fluctuations compared to mammals. However, it must be considered that ectothermic organisms have evolved many thermal adaptations through physiological and behavioural measures to mitigate the resulting oxidative stress. However, further research in the fields of ecology, biogeography and evolution is needed to determine the exact effects of temperature on oxidative stress and the resulting changes in life characteristics in wild populations.Temperatura je glavni abiotički čimbenik i ima izravan utjecaj na fiziologške procese organizma. Nadalje, temperatura utječe na gotovo sve ostale okolišne čimbenike koji utječu na žive organizme. Predviđa se da će ektotermni organizmi zbog klimatskih promjena biti izloženi velikom riziku zbog njihove ovisnosti o temperaturi okoliša za održavanje tjelesne temperature. Gmazovi su ektotermni kralješnjaci, koji su kao i ostali ektotermni organizmi osjetljivi na temperaturne promjene. Metabolizam, rad mišića i živčanog sustava te reprodukcija ovisni su o tjelesnoj temperaturi gmazova. Za razumijevanje utjecaja temperature na oksidativni stres, nužno je razjasniti mehanizam nastanka reaktivnih kisikovih spojeva (ROS) te kako spriječiti nastanak oksidativnog stresa. U ovom radu opisat će se oksidacijsko-antioksidacijski procesi i oksidativni stres uzrokovan toplinskim učincima u gmazova. U metaboličkim procesima aerobnih organizama, ROS se kontinuirano stvaraju kao nusproizvodi oksidacijsko-redukcijskih reakcija te primarno nisu štetni. Štoviše, ROS su neophodni za brojne fiziološke funkcije, primjerice za proizvodnju energije i procese imunološkog sustava. Potencijalni štetni učinak reaktivnih kisikovih radikala/spojeva u fiziološkim uvjetima sprječava antioksidativni zaštitni sustav. Oksidativni stres nastaje kada je ravnoteža između oksidacijskog i antioksidativnog sustava poremećena zbog prekomjerne razine ROS-a ili smanjenja antioksidansa. Poznato je da je brzina metabolizma gmazova u korelaciji s temperaturom okoliša, što ih čini fiziološki osjetljivijima na promjene temperature u usporedbi sa sisavcima. No, potrebno je uzeti u obzir da su ektotermni organizmi razvili niz prilagodbi na promjenu temperature, putem fizioloških i bihevioralnih mehanizama te time ublažili nastali oksidativni stres. Međutim, da bi se utvrdio stvarni učinak temperature na oksidativni stres i posljedične promjene životnih obilježja u divljih populacija, potrebna su dodatna istraživanja u područjima ekologije, biogeografije i evolucije

Effect of the post weld heat treatment on the microstructure of the underwater wet welding SS400 steel

The effects of the post weld heat treatment (PWHT) on the microstructure and hardness of the underwater wet welding (UWW) SS400 steel have been evaluated. The UWW was performed using Shielded Metal Arc Welding (SMAW) in water depth of 5.0 m, while PWHT was carried out on underwater welded specimen with temperature of 660 oC for 75 minutes. The result showed that the PWHT caused increasing the grain size of the microstructure and decreasing in hardness

Effect of quenching temperature on microstructure and mechanical properties of 50CrVA spring steel for mountain bike shock absorber

In order to improve the quality of people ‘s cycling and improve the safety performance of mountain bikes. The effects of quenching temperature on the microstructure and mechanical properties of 50 CrVA spring steel for mountain bike shock absorber were studied by means of microstructure observation, tensile test and impact test. The results show that the microstructure of 50CrVA steel is tempered troostite after quenching at 860-940 °C and tempering at 450 °C. In the quenching temperature range of 860 ~ 940 °C, with the increase of quenching temperature, the yield strength, tensile strength and elongation of 50CrVA steel increase first and then decrease, and reach the maximum at 920 °C, while the impact energy shows the opposite trend. When the quenching temperature is 920 °C and the tempering temperature is 450 °C, the comprehensive mechanical properties of 50CrVA steel are the best. At this time, the yield strength is 1 419MPa, the tensile strength is 1 538MPa, the elongation is 12 %, and the impact energy is 20,2J

Rapid spread of the Mediterranean glycophyte Catapodium rigidum in Hungary

This paper discusses the spread of the Mediterranean plant Catapodium rigidum (L.) C.E. Hubb. in Hungary, which is found in the transition zone between the sub-Mediterranean and continental climatic zones of Central Europe. This alien species has been found at 12 new localities in Hungary in recent years. Some of these stands are located along main roads, while others are found in urban weed vegetation. The species was most likely introduced by increasing road traffic and tourism. Our preliminary findings suggest that the spread of the species is not concentrated along main roads due to its salt sensitivity. Instead, it is more likely to be found in xerothermic weed vegetation in urban areas where salting and winter de-icing are not applied

Klinička procjena učinkovitosti meloxiveta u kompleksnom liječenju mačaka s karcinomom mliječne žlijezde

This study presents the results of a clinical administration of meloxivet nonsteroidal anti-inflammatory treatment against the background of the docetaxel + cyclophosphamide regimen chemotherapy following bilateral mastectomy in cats with mammary gland carcinoma. The inclusion of meloxivet in complex chemotherapy against breast carcinomas bilateral mastectomy improved treatment results. In particular, survival was extended in the clinical stages: I and II - by 1.3 times, III - by 1.6 times, and the disease-free period was increased by 1.5, 1.4 and 1.9 times, respectively. Complex treatment of cats including non-steroidal anti- inflammatory therapy reduced the risk of disease progression depending on the clinical stage during the first six months after the end of the course. An increase in the number of patients with subsequent metastasis (after six to twelve months) was also noted. The use of meloxivet made it possible to avoid disease progression in cats up to three years of age, and to reduce its probability and delay the onset of metastasis in all age categories. The proposed scheme of treatment of cats with mammary gland carcinomas reduced side effects, indicating an insignificant risk of negative effects of long-term meloxivet use against the background of a 1.5- fold reduction in the frequency of recurrences in the surgical intervention area.Ovaj rad predstavlja rezultate kliničkog istraživanja metronomske uporabe meloxivet nesteroidnog protuupalnog lijeka u usporedbi s DC (docetaksel + ciklofosfamid) režimom polikemoterapije nakon bilateralne mastektomije u mačaka s karcinomom mliječne žlijezde. Uključivanje meloxivet nesteroidnog protuupalnog lijeka u metronomski režim u kompleksnoj kemoterapiji kod bilateralne mastektomije zbog karcinoma mliječne žljezde pouzdano omogućuje (Р<0,001) poboljšanje rezultata liječenja. Posebice, produljenje razdoblja preživljavanja u kliničkoj fazi T1 N0 M0 (s 25,6±2,2 na 32,7±2,5 mjeseci), T2 N0 M0 (s 16,8±1,7 na 22,4±1,3 mjeseca), T1-2 N1 M0 (s 12,9±0,9 na 17,2±1,0 mjesec) za 1,3 puta, III (T3 N0-1 M0) za 1,6 puta (s 8.3±1.4 na 13,1±1,5 mjeseci) i razdoblje bez bolesti za 1,5 (s 14,0±1,8 na 21,1±2,2 mjeseca), 1,4 (s 12,8±1,9 na 18,1±1,3 mjeseca), 1,9 (s 7,2±1,0 na 13,5±1,6 mjeseci), odnosno 1,9 puta (s 4,4±0,5 na 8,3±0,8 mjeseci). Kompleksno liječenje mačaka koje je uključivalo nesteroidnu protuupalnu terapiju, ovisno o kliničkoj fazi tijekom prvih šest mjeseci nakon završetka tretmana s 22,2-70,0 % na 12,5-33,3 % smanjilo je rizik od progresije bolesti. Istovremeno, zamijećen je povećani broj pacijenata u kojih su se metastaze pojavile kasnije (nakon šest do dvanaest mjeseci). Uporaba meloxivet nesteroidnog protuupalnog lijeka omogućila je izbjegavanje progresije bolesti u mačaka do tri godine starosti te smanjenje vjerojatnosti i odgodu nastanka metastaza u svim dobnim kategorijama. Predložena shema liječenja mačaka s karcinomima mliječne žlijezde omogućila je smanjenje razine nuspojava, pokazujući beznačajan rizik od negativnih nuspojava na tijelo zbog dugoročne uporabe meloxiveta u odnosu na smanjenje učestalosti ponavljanja u kirurškom interventnom području za 1,5 puta

Forenzičke znanosti u veterinarskoj medicini: interdisciplinarni predmet koji treba specijalizaciju

Forensic sciences have multiple applications in the medical sciences, including veterinary medicine, particularly in animal crime and welfare, and food safety inspection. However, there is no formal specialisation for veterinarians working in this field. There is a current need for formal training and recognition to provide better service to the community, and to ensure suitable basic training for general veterinary professionals working in different fields.Forenzičke znanosti imaju višestruke primjene u medicinskim znanostima, uključujući veterinarsku medicinu, tj. u zločinima počinjenima nad životinjama i dobrobiti životinja, kao i kod provjere zdravstvene ispravnosti hrane. Međutim, ne postoji formalna specijalizacija za veterinare koji djeluju na ovom polju. Trenutačno postoji potreba za formalnom obukom i priznavanjem da bi se pružile bolje usluge zajednici i osigurala prikladna osnovna obuka stručnjacima veterine općenito koji rade na različitim poljima

Research on conical plug valve piezoelectric pump applied to metallurgical equipment colling

In this paper, a valve piezoelectric pump structure is proposed, which provides a method for the cooling of metallurgical equipment and avoids the hidden danger of damage to key components due to long-term exposure to high temperatures. In this paper, the research results of simulated flow rate and test flow rate of valved piezoelectric pump are introduced. The results show that the flow rate of the pump is sensitive to the influence of driving voltage, and it has certain feasibility for the cooling of metallurgical equipment

Research on vision system of intelligent sorting robot based on deep learning

It is an important step to realize automatic and intelligent production of coal mine to use intelligent sorting robot instead of manual. The vision system, as the “eye” of the intelligent sorting robot, completes the rapid identification, positioning and grouping of the sorting target. Based on YOLOv5, the vision system uses GhostNet to carry out the lightweight design of the model, aiming to ensure the detection accuracy while making the entire model more lightweight, so as to improve the model recognition speed and reduce the operating cost. The model recognition speed of Ghost-YOLOv5 designed and developed is 33FPS, the model size is only 4,2 Mb, and the average detection accuracy is 96,7 %

Prvo izvješće o prisutnosti potencijalno patogene bakterije Vibrio parahaemolyticus u uzgojenih dagnji (Mytilus galloprovincialis) istarskoga akvatorija ostvaren primjenom mikrobioloških i molekularnih metoda

Microbiological and molecular PCR techniques were used to analyse 328 samples of mussels (Mytilus galloprovincialis) cultured in Istrian waters. Molecular testing was more effective than microbiological testing, detecting the presence of the bacterium Vibrio parahaemolyticus in 21.34% of samples, compared to 2.44% detected through microbiological methods. The probability of detecting the presence of this bacterium was 7.19 times higher when the sea surface temperature was above 15°C, while thermostable direct hemolysin (TDH) and TDH-related hemolysin (TRH) positive samples were detected at sea temperatures above 22.5°C and 24.7°C, respectively. TDH- and TRH-positive samples constituted 10% of the total V. parahaemolyticus-positive samples. As there is no legal obligation to monitor the presence of this bacterium, consuming raw or insufficiently cooked mussels can lead to illness.Primjenom mikrobioloških i molekularnih tehnika, pretraženo je 328 uzoraka školjkaša dagnji (Mytilus galloprovincialis), uzgojenih na području istarskoga akvatorija. Rezultati ukazuju na smanjenu osjetljivost mikrobiološke tehnike (2.44 %) u odnosu na molekularnu dijagnostiku kojom je dokazana prisutnost bakterije V. parahaemolyticus u 21,34 % uzoraka. Izgledi za dokazivanje prisutnosti ove bakterije su 7,19 puta veći kada je površinska temperatura mora veća od 15 °C, dok su geni za kodiranje termostabilnog direktnog hemolizina (TDH) i hemolizina ovisnog o TDH (TRH) u uzorcima dokazani pri temperaturama mora iznad 22,5 °C, odnosno 24,7 °C. Udio TDH i TRH pozitivnih uzoraka iznosio je 10 % od ukupnih 70 V. parahaemolyticus-pozitivnih uzoraka. S obzirom na nedostatak zakonske obveze praćenja prisutnosti ove bakterije moguće je oboljevanje ljudi nakon konzumacije sirovih ili termički nedostatno obrađenih školjkaša

Procjena implementacije biosigurnosnih mjera na stočarskim farmama u trima regijama Kosova

Biosecurity is a multicomponent procedure that encompasses risk analysis and management strategies relevant to human, animal and plant life, as well as environmental risk assessment. The aim of this study was to assess data related to biosecurity measures implemented by farmers on cattle, sheep and goat farms in Kosovo. A total of 36 farms from three regions of Kosovo, Pristina, Ferizaj and Peja were included. A questionnaire consisting of one open-ended question and 37 closed questions was administered directly to farmers, and the current on-farm situation was observed by the investigators. Based on the collected results, 86% of farms were cattle farms, 8% were sheep farms, and 6% were goat farms. Among all the farms visited, 67% of them operated with a combined system, 28% with a closed system and only 5% operated with an open system. The vast majority of participants (81%) declared that they did not have sufficient knowledge about the term biosecurity, whereas 11% of them were moderately familiar with the term biosecurity and only 8% of them were quite familiar with the term. 83% reported that their animals undergo a veterinary health check only when necessary. Other biosecurity measures applied less frequently included: showering before entering the farm, specific clothing and shoes for visitors, animal quarantine, disinfection and systematic plan for insect and rodent control. We propose that there is room for improving the level of on-farm biosecurity by enhancing practical training and information from local institutions. We conclude that routine integration of biosecurity measures was not demonstrated by most farmers in their management practices and that there is significant room for improvement concerning the level of biosecurity in Kosovo.Biosigurnost je višekomponentni postupak koji obuhvaća analizu rizika i strategije upravljanja bitne za život ljudi, životinja i biljaka, kao i procjenu rizika vezanih uz okoliš. Cilj je ovog istraživanja bio procijeniti podatke vezane uz biosigurnosne mjere koje provode farmeri na farmama goveda, ovaca i koza na Kosovu. U istraživanje je bilo uključeno ukupno 36 farmi iz tri regije Kosova: Prištine, Uroševca i Peći. Upitnik koji se sastojao od jednog otvorenog i 37 zatvorenih pitanja primijenjen je izravno poljoprivrednicima, a istraživači su promatrali trenutnu situaciju na farmi. Na temelju prikupljenih rezultata, 86 % gospodarstava su: govedarske, 8 % ovčarske, a 6 % kozarske. Od svih posjećenih farmi, njih je: 67 % radilo je kombiniranim 28 % zatvorenim i samo 5 % otvorenim sustavom. Velika većina sudionika (81 %) izjavila je da nema dostatno znanja o pojmu biosigurnosti, dok je njih 11 % bilo osrednje upoznato, a samo 8 % njih bilo je dobro upoznato s pojmom. Njih 83 % izjavilo je da njihove životinje prolaze veterinarski zdravstveni pregled samo kada je to potrebno. Ostale biosigurnosne mjere koje su se rjeđe primjenjivale su: tuširanje prije ulaska na farmu, posebna odjeća i obuća za posjetitelje, karantena životinja, dezinfekcija i sustavni plan kontrole insekata i deratizacije. Zaključili smo da ima prostora poboljšanje razine biološke sigurnosti na farmama jačanjem praktične obuke i informacija od lokalnih institucija, ali i da većina poljoprivrednika ne pokazuje rutinsku integraciju biosigurnosnih mjera u svojim praksama upravljanja i da razina biološke sigurnosti na Kosovu ima velikih mogućnosti u poboljšanju