Potencijali rasta rukole Diplotaxis tenuifolia (L.) DC. proučavani su tijekom 30 dana uzgoja u komori pri različitim režimima osvjetljenja; T5_ max 630 nm, LED1_ max 545 nm i LED2_max 599 nm. Nije ...bilo značajnih razlika u suhoj težini nakon 15 dana, međutim, od 15. do 30. dana, povećanje suhe težine bilo je značajno najveće pod LED2. Dobro se slaže s procijenjenom prosječnom površinom lista (LA) po biljci (43,83 cm2 ), te povećanjem LA (39,70 cm2 ) i ukupnom svježom masom (7,898 g po biljci). Regresijskom analizom utvrđena je najjača korelacija između suhe težine i intenziteta svjetla PPFD_R (0,792**), što pokazuje pozitivan učinak dodatne LED rasvjete u usporedbi sa standardnim T5 svjetlom.
Rad obrađuje dimenzijske značajke utovarnoga prostora forvardera, a koje norma ISO 13860 (2016) određuje trima dimenzijama zasnovanim na neposrednom mjerenju (duljina utovarnoga prostora, širina ...između držača tereta, visina držača tereta) te dvjema posrednim (računske) dimenzijama (površina poprečnoga presjeka utovarnoga prostora forvardera i visina težišta tereta). Iako za te pokazatelje utovarnoga prostora forvardera norma ISO 13860 (2016) daje definicije, za dva računska pokazatelja nije objašnjen način njihova izračuna te na kojim se dimenzijama utovarnoga prostora zasnivaju.Poticaji za pisanje ovoga rada jesu: 1) pojašnjenje važnosti poznavanja dimenzijskih pokazatelja utovarnoga prostora forvardera, 2) izrada prijedloga načina izračuna poprečnoga presjeka utovarnoga prostora forvardera i visine težišta tereta forvardera te 3) određivanje dodatnih potrebnih mjernih dimenzijskih značajki utovarnoga prostora.Na osnovi predloženih mjerenja prikazane su dimenzije, ali i računske značajke utovarnoga prostora osmokotačnoga forvardera Komatsu 875.
The paper deals with the dimensional characteristics of the forwarder loading space, which is determined by ISO 13860 (2016) through three dimensions based on direct measurement (distance of load bunk headboard to rearmost bunk, width across stakes, stake height) and two indirect (calculative) dimensions (cross-sectional area of load space and height of load centre). Although the ISO 13860 (2016) standard provides definitions for the listed indicators of the forwarder loading space, the method of their calculation, as well as the dimensions of the loading space, are not explained for the two calculative indicators. The aim of this paper was to: 1) clarify the importance of knowing the dimensional indicators of forwarder loading space; 2) draft a proposal for calculating the cross-sectional area of forwarder load space and height of load centre; and 3) determine additional (required) dimensional characteristics of loading space. Based on the proposed measurements, the dimensions and computational characteristics of the loading space of the eight-wheeled Komatsu 875 forwarder are presented.
Recent years have seen much attention being given to self-assembly of dipeptide-based structures, especially to self-regulation of dipeptide structures with different amino acid sequences. In this ...study we investigated the effects of varying solvent environments on the self-assembly of glycine-histidine (Gly-His) dipeptide structures. First we determined the morphological properties of Gly-His films formed in different solvent environments with scanning electron microscopy and then structural properties with Fourier-transform infrared (FTIR) spectroscopy. In addition, we studied the effects of Gly-His films on silver nanoparticle (AgNP) formation and the antioxidant and cytotoxic properties of AgNPs obtained in this way. We also, assessed antibacterial activities of Gly-His films against Gram-negative
and
and Gram-positive
. Silver nanoparticle-decorated Gly-His films were not significantly cytotoxic at concentrations below 2 mg/mL but had antibacterial activity. We therefore believe that AgNP-decorated Gly-His films at concentrations below 2 mg/mL can be used safely against bacteria.
U ranoj fazi kod opeklinskih ozljeda može se dati samo gruba prognoza o trajanju liječenja. Mi smo stoga proveli analizu povezanosti mehanizma ozljede s omjerom prosječnog trajanja hospitalizacije ...(PTH) i ukupne površine tijela zahvaćenom opeklinom (UPT). Proveli smo retrospektivnu analizu 375-ero pacijenata koji su u razdoblju između 1. siječnja 2010. i 31. prosinca 2019. hospitalizirani zbog opeklinskih ozljeda na Klinici za dječju kirurgiju Klinike za dječje bolesti Zagreb. Pacijenti su s obzirom na mehanizam nastanka ozljede razdijeljeni u sljedeće podskupine - opekline vrućom vodom (n=210), opekline vrućim uljem (n=22), opekline padom u vruću vodu (n=7), kontaktne opekline (n=54), opekline plamenom (n=36), opekline vrućim parama (n=7), eksplozivne opekline (n=13) i opekline strujnim udarom (n=12). Analizirali smo omjer prosječnog trajanja hospitalizacije (PTH) i ukupne površine tijela (UPT) s obzirom na mehanizam opeklinske ozljede. Kontaktne opekline nose veći rizik za veći omjer trajanja hospitalizacije s ukupnom površinom tijela (PTH/UP) od opeklina vrućim uljem (t=2,485, p= 0,015), opeklina vrućom tekućinom (t=3,948, p < 0,001), opeklina plamenom (t= 2,485, p= 0,015), eksplozivnih opeklina (t=2,900, p= 0,005), opeklina zbog pada u vruću vodu (t=4,369, p<0,001) te od opeklina parom (t=4,369, p< 0,001). Opekline plamenom nose veći rizik za veći PTH/UPT omjer od opeklina vrućom tekućinom (t=2,105, p= 0,039), opeklina parom (t=2,848, p= 0,009) te od opeklina nastalih zbog pada u vruću vodu (t=2,846, p= 0,009). Opekline vrućim uljem nose veći rizik za veći PTH/UPT omjer od opeklina parama (t= 2,317, p= 0,029) ili opeklina nastalih zbog pada u vruću vodu (t= 2,263, p= 0,033). Različiti mehanizmi kod opeklinskih ozljeda rezultiraju različitim ishodima što se tiče omjera prosječnog trajanja hospitalizacije i površine tijela zahvaćene opeklinom. U slučaju kontaktnih opeklina može se očekivati najdulje trajanje hospitalizacije s obzirom na ukupnu površinu tijela zahvaćenu opeklinom. Naši rezultati upućuju na to da mehanizam nastanka ozljede ima prognostičku vrijednost u smislu trajanja hospitalizacije.
A new method for the composite rolling of 304/Q345R was explored in the present study. The composite interface of the composite plate was studied using a scanning electron microscope (SEM) and ...electron-backscatter diffraction (EBSD). The results showed that a composite interface was formed with corrugated connections, increasing the length of the composite interface. Furthermore, the elongation of the corrugated interface relative to the original wave interface and the original horizontal interface were 29.43 % and 59.12 %, respectively. The composite interface became a 3D ripple interface from the traditional 2D plane. In the EBSD analysis, the strain energy at the interface of the corrugated composite interface was large, especially in the composite interface of the wave-waist position, indicating that the position of the ripple interface had a large deformation degree. This deformation is beneficial to the interface oxide and broken hardened layer conducive to the interface of the complex.
Bukva predstavlja jednu od najvažnijih vrsta drveća u Bosni i Hercegovini. Stoga, potrebno je praćenje zdravstvenog stanja bukovih sastojina i poduzimanje svih neophodnih preventivnih i represivnih ...mjera kako bi se zdravstveno stanje ovih sastojina unaprijedilo. U okviru istraživanja analiziran je utjecaj bukove skočipipe na površinu oštećenja listova na stabalcima bukve od imaga i ličinke u ovisnosti od lokacije i položaja stabalaca bukve u sastojini (svjetlo/sjena). Lokacije istraživanja su se nalazile unutar kulture smreke, visokih šuma bukve i mješovitih šuma bukve i jele sa smrekom. Bukova skočipipa predstavlja jednog od glavnih defolijatora koji se javljaju na stablima bukve. Uzorak istraživanja čine 15 stabalaca bukve, po 5 stabalaca na tri lokacije. Na svakoj lokaciji odabrana su 3 stabalca čija krošnja je bila na svjetlu i dva stabalca čija krošnja je bila u sjeni (ukupno 9 stabalaca na svjetlu i 6 stabalaca u zasjeni). Na svakom stablu pregledavana su i mjerena oštećenja od imaga i ličinke bukove skočipipe. Ustanovljeno je da prosječna površina oštećenja lista bukve od imaga je varirala od 2-4%, a ličinke od 4-8%. Statističkim analizama je utvrđeno postojanje statistički značajnih razlika u površini oštećenja lista bukve od ličinke u ovisnosti od položaja stabalaca bukve u sastojini.
The impact of beech weevil on the damaged area of beech trees from adult and larvae was analyzed, depending on the location and position of trees of beech in stand (sun/shadow). The research localities were located within the forest plantation of spruce, natural beech forests and mixed beech, fir and spruce forests. Beech weevil represents one of the main defoliators appearing on beech trees. The research sample consists of 15 beech trees, 5 trees per location, on three locations. On each location, were selected 3 trees with the crown in the sun and 2 trees with the crown in the shade (a total of 9 trees in the sun and 6 trees in the shade). On each tree were measured damages from the adult and larvae of beech weevil. It has been found that the average damaged area on beech leaf varied for adult from 2-4%, and larvae 4-8%. Statistical analysis showed a statistically significant differences in damaged areas of beech leaf from larvae, depending on the position of beech trees in the stand.
Hrast crnika (
Quercus ilex
L.) je sredozemna vazdazelena vrsta drveća, koja na svom području pridolaska pokazuje veliku morfološku i funkcionalnu varijabilnost. Cilj ovoga rada bio je utvrditi ...postoji li diferencijacija hrasta crnike na klimatskom gradijentu istočne obale Jadranskoga mora (opisanom s prosječnom godišnjom količinom oborina, prosječnom količinom oborina tijekom ljetnog perioda i klimatskim deficitom vlage) s obzirom na funkcionalne značajke lišća (opisane sa specifičnom lisnom površinom, indeksom relativnog sadržaja ukupnih klorofila u lišću i stopom neto fotosinteze mjerene u lišću). Specifična lisna površina mjerena je na lišću uzorkovanom u tri provenijencije na prirodnom staništu te lišću uzorkovanom u pokusnom nasadu na mladim biljkama porijeklom iz tih istih provenijencija. U pokusnom nasadu mjeren je i indeks relativnog sadržaja ukupnih klorofila i stopa neto fotosinteze. Provenijencija Pula u odnosu na provenijencije Zadar i Bar ima veću specifičnu lisnu površinu te manji indeks relativnog sadržaja ukupnih klorofila i stopu neto fotosinteze. To potvrđuje prilagodbu provenijencije Pula na vlažnije stanište, a provenijencija Zadar i Bar na suše stanište te ujedno ukazuje na funkcionalnu diferencijaciju provenijencija hrasta crnike na istočnoj obali Jadranskoga mora s obzirom na klimatske prilike. Isti obrazac diferencijacije prema specifičnoj lisnoj površini u prirodnim sastojinama i pokusnom nasadu ukazuje na ekotipsku diferencijaciju istraživanih provenijencija. Prema tomu, hrast crnika mogao bi imati značajnu mogućnost funkcionalne prilagodbe na promijenjene klimatske uvjete.
Holm oak (
Quercus ilex
L.) is an evergreen tree species with natural distribution within the Mediterranean, from Portugal and Morocco on the west to the western coast of Turkey on the east part of its range. On the eastern coast of the Adriatic Sea, it occupies warmer localities on the coast of Istria and northern Adriatic islands while on the southern Adriatic islands as well as on the narrower coastal area south of Zadar it has a more continuous distribution. Given the size of the area of distribution, holm oak shows a big morphological and functional variability so certain populations differ according to the climate conditions in their area. This fact has been very well researched in the western and central part of its range, while the data for the eastern part, and thus for the eastern coast of the Adriatic Sea, are scarce. The great morphological and functional variability of holm oak reflects its great phenotypic plasticity. Although phenotypic plasticity is conditioned by the environment, it can also have a genetic basis through local adaptation to the established environmental conditions in different parts of the species’ area of distribution. The aim of this study was to determine whether there is a differentiation of holm oak down the climatic gradient of the eastern Adriatic coast with respect to the functional characteristics of its leaves.
The research was conducted on three provenances of holm oak from the area of Pula and Zadar in the Republic of Croatia and Bar in Montenegro. During the winter of 2019, 12 leaves were sampled per 12 trees in each provenance in order to determine the specific leaf area (SLA). Additionally, acorns were collected beneath those trees with which an greenhouse experiment was established. In the experiment, a total of 64 plants were grown, of which 22 plants from the provenances of Pula and Zadar, and 20 plants from the provenance of Bar. In the second part of the vegetation period in 2020, one leaf was sampled from each plant with the aim of determining the specific leaf area (SLA). In addition, the rate of net photosynthesis (A) and the relative total chlorophyll content index (CCI) were measured in the greenhouse experiment. Measurements were performed in July and September of 2020. A was measured using a portable gas exchange measuring device LCpro + (ADC BioScentific, 2007), while the CCI was measured using the CCM-200 (Opti-Sciences, Tyngsboro, MA).
Analysis of the variance revealed a statistically significant difference among the studied provenances for most of the measured characteristics both on the leaves sampled in the natural habitat and on the young plants in the experimental plantation. Previous research on holm oak indicates that there is a functional differentiation of provenances on different climatic gradients in the central and western Mediterranean, with our results confirming this on the eastern coast of the Adriatic Sea. Young plants in the experimental plantation retain the same pattern of differentiation with respect to SLA as their mother trees in natural stands (Figure 1c). Such a result indicates that the differentiation of holm oak provenances is at least partly the result of genetic adaptation to local habitat conditions, i.e. that the holm oak on the eastern Adriatic coast as well as in other parts of its range could distinguish ecotypes. The sclerophilicity of the leaves described by SLA (Figure 1c) does not coincide with the average annual rainfall (Figure 1a), but with the amount of precipitation in the summer (Figure 1b) and the climate deficit of moisture (Figure 2a). The established pattern of provenance differentiation with respect to SLA and climatic conditions is followed by A measured on young plants in the experimental plantation. Therefore, Pula, which has the highest SLA and comes in the least arid climatic conditions, has the lowest A, while Zadar, which has the lowest SLA and comes in the most arid conditions, shows the highest values of A (Figures 1 and 2). This is in line with the literature that shows that the intensity of photosynthesis per unit leaf area in holm oak decreases with increasing SLA (Niinemets 2015, Peguero-Pina et al. 2017). Namely, the anatomical structure of holm oak leaves is adapted in such a way that those leaves that have a lower SLA also have better conductivity of CO2 through the mesophilic leaves and contain more nitrogen per unit area. Accordingly, the provenances of Zadar and Bar compared to the provenance of Pula had a lower SLA (Figure 1c) and a higher CCI (Figure 2b) which has a positive correlation with the nitrogen content in the leaves.
Holm oak could have a significant ability to functionally adapt to different climatic conditions. Accordingly, when considering the impact of climate change on natural populations of holm oak, its phenotypic plasticity should be considered, as well as the observed functional ecotypic differentiation.
U članku se najprije izlažu dva različita načina rješavanja (primjenom diferencijalnoga računa i bez njega) poopćenja zadatka postavljenoga na višoj razini matematike na državnoj maturi u kolovozu ...2022.:
Pravac prolazi točkom T (xT > 0; yT > 0) i s pozitivnim dijelovima koordinatnih osi određuje trokut optimalne površine. Kolika je mjera kuta kojega taj pravac zatvara s osi ordinata?
Opisuje se i konstrukcija pravca iz zadatka. Potom se analizira postojanje optimalne površine u slučaju slabijega zahtjeva da pravac siječe obje koordinatne osi. Zaključno se navode i komentiraju neke varijante zadatka u kojima se točka T nalazi u nekom od preostalih triju kvadranata pravokutnoga koordinatnoga sustava u ravnini.
U Republici Hrvatskoj, u razdoblju od 1885. do 2010. godine, požete površine pod pšenicom rasle su do 1964. godine (od 190.000 ha u 1885. god. do 442.000 ha u 1964. god.), a od tada do danas bilježi ...se pad sve do 2010. godine kada je bila požeta najmanja površina od 141.000 ha. U razdoblju 1885-2010. god., proizvodnja pšenice varirala je od najmanjih 155.000 tona 1897. godine, dok je rekordna proizvo-dnja od 1.6 milijuna tona ostvarena 1990. godine. Promatrajući prosječne prinose, najniži prosječni prinos iznosio je 658 kg/ha (1897. god.), a najveći prinos od 5.483 kg/ha ostvaren je u 2008. godini. U promatranom razdoblju požete površine smanjivale su se na godišnjoj razini od 238 ha, dok su ukupna proizvodnja i prosječni prinosi rasli na godišnjoj razini u iznosu od 8.888 tona ili 37 kg/ha. Analizirajući pojedina razdoblja rezultati pokazuju da su u razdoblju 1885-1914. god. požete površine i proizvodnja rasle na godišnjoj razini od 6.760 ha i 5.473 tone, a prosječni prinosi zrna 5,7 kg/ha/godišnje. U razdoblju 1921-1939. god. požete površine i proizvodnja rasli na godišnjoj razini 2.813 ha i 5.618 tona, a prosječni prinosi zrna 6,5 kg/ha/godišnje. U razdoblju 1945-1991. god. požete površine su se smanjivale na godišnjoj razini od 1.080 ha. Proizvodnja je kontinuirano rasla na godišnjoj razini od 25.026 tona, a prosječni prinos zrna 84 kg/ha/ godišnje. U razdoblju 1992-2010. god. trend smanjivanja požetih površina se nastavio na godišnjoj razini od 2.168 ha, dok je za proizvodnju utvrđeno godišnje smanjivanje od 64 tona. Prosječni prinos zrna rastao je prosječno 61 kg/ha/godišnje.
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