Evidence of microbial activity in siderite and calcite deposits on gastropod shells in Pliocene sand and clay beds from Lipovljani, Croatia

Freshwater Pliocene sand and clays found near Lipovljani in western Slavonia, Croatia, contain gastropods preserved by diagenetic mineral incrustations of alternating calcite and siderite. The geochemical possibility of siderite formation is evaluated, and evidence for microbial mediation of siderite deposition around fossil carbonate shells is presented

Quaternary Depositional Environments in the Vrgoračko Polje/Lake (SE Croatia)

The Vrgoračko polje is a karst field with a surface area of 37 km2 and an altitude of between 20 and 28 m above sea level, situated at the southern edge of the Dalmatian Zagora. During the Quaternary the polje was flooded for variable periods of time and a lacustrine environment was established. A multidisciplinary study of drill-cores, outcrops and geoelectric measurements recognised five main sedimentary facies: laminated sediment, redeposited sediment, coarse grained carbonate debris, littoral clay and lacustrine chalk. Based on the facies analysis, depositional environments developed during the Holocene include aquatic lacustrine littoral and deeper-water environments. The terrestrial environment is represented by a desiccated lake phase. The littoral clay facies (filling depressions and caverns in the karst relief) is laterally equivalent to the deep-water laminated facies (varves?). A stratigraphic break between littoral claya nd lacustrine chalk could be time-equivalent to disturbed laminated sediments deposited in deeper-water and to local intercalations of coarse-grained carbonate debris in shallow-water facies sediments. These features could have been the result of a neotectonic event (earthquake), which triggered debris flows of colluvial material from slopes around the lake, and this could also have changed the hydrological regime of the Vrgoračko polje and affected subsequent depositional facies. According to 14C dating, deposition of the lacustrine chalk started at the beginning of the Mid-Holocene Warm Period (7686±36 aBP) with a sedimentation rate of approximately 0.51 mm a-1 during the Middle, and 0.58 mm a-1 during the Late Holocene to today. Calculated carbonate production was estimated at 1050 gm-2 a-1. A temporary phase of subaerial exposure of the lake is indicated by desiccation cracks and two bioturbated palaeosol horizons. The described depositional environments and sediment facies found in the Vrgoračko polje could be considered to represent a typical Quaternary lacustrine sedimentation pattern for other Dinaric karst poljes.  </span

The Cenomanian–Turonian Boundary in the Northwestern Part of the Adriatic Carbonate Platform (Ćićarija Mtn., Istria, Croatia): Characteristics and Implications

The Cenomanian–Turonian boundary (CTB) in the Ćićarija Mountain region (northern Istria, Croatia) is characterized by calcisphere limestone successions with a firmground and glauconite horizon, bioturbated intervals, tempestites, and slumped structures as well as microbially laminated and organic-rich interbeds deposited in the northwestern part of the intra-Tethyan Adriatic Carbonate Platform (AdCP). Compilation of the results from three studied sections (Vodice–Jelovica, Martinjak and Planik) of litho-, bio-, and microfacies analyses, X-ray diffraction, SEM, EDS, and stable isotope analyses allowed reconstruction of marine paleoenvironmental conditions during this time period. Shallow-marine carbonate deposits of the Milna Formation underlie a drowned-platform succession of the Sveti (Sv.) Duh Formation. The contact between these two formations is sharp and commonly marked by slumped deposits. The Sv. Duh Formation consists of about 100 m of calcisphere wackestone enriched in organic matter. The results of preliminary δ13C and δ18O stable isotope analyses indicate the influence of the global Oceanic Anoxic Event (OAE2) on the deposition of this carbonate succession. Anoxic and hypoxic conditions in the water column lead to major changes in the shallow-marine carbonate system of the AdCP. Numerous benthic foraminifera declined during that time, but planktonic foraminifera and calcareous dinoflagellates diversified and expanded greatly. The results of this research provide new insights into the character of the CTB interval in this part of the Tethyan realm. Local and regional synsedimentary tectonics combined with global upper Cretaceous sea-level dynamics allows the correlation of the investigated deeper-marine lithostratigraphic units with OAE2

Stable gastric pentadecapeptide BPC 157 may counteract myocardial infarction induced by isoprenaline in rats

We revealed that the stable gastric pentadecapeptide BPC 157, a useful peptide therapy against isoprenaline myocardial infarction, as well as against isoprenaline myocardial reinfarction, may follow the counteraction of the recently described occlusion-like syndrome, induced peripherally and centrally, which was described for the first time in isoprenaline- treated rats. BPC 157 (10 ng/kg, 10 µg/kg i.p.), L-NAME (5 mg/kg i.p.), and L-arginine (200 mg/kg i.p.) were given alone or together at (i) 30 min before or, alternatively, (ii) at 5 min after isoprenaline (75 or 150 mg/kg s.c.). At 30 min after isoprenaline 75 mg/kg s.c., we noted an early multiorgan failure (brain, heart, lung, liver, kidney and gastrointestinal lesions), thrombosis, intracranial (superior sagittal sinus) hypertension, portal and caval hypertension, and aortal hypotension, in its full presentation (or attenuated by BPC 157 therapy (given at 5 min after isoprenaline) via activation of the azygos vein). Further, we studied isoprenaline (75 or 150 mg/kg s.c.) myocardial infarction (1 challenge) and reinfarction (isoprenaline at 0 h and 24 h, 2 challenges) in rats (assessed at the end of the subsequent 24 h period). BPC 157 reduced levels of all necrosis markers, CK, CK-MB, LDH, and cTnT, and attenuated gross (no visible infarcted area) and histological damage, ECG (no ST-T ischemic changes), and echocardiography (preservation of systolic left ventricular function) damage induced by isoprenaline. Its effect was associated with a significant decrease in oxidative stress parameters and likely maintained NO system function, providing that BPC 157 interacted with eNOS and COX2 gene expression in a particular way and counteracted the noxious effect of the NOS- blocker, L-NAME

Drusus medianus Marinkovic-Gospodnetic 1976

Description of fifth instar larva of &lt;i&gt;Drusus medianus&lt;/i&gt; &lt;p&gt;Case and Larva&lt;/p&gt; &lt;p&gt;Case constructed completely of mineral particles (Fig. 16), slightly curving, total length 9.98&ndash;12.55 mm, width of anterior part 2.42&ndash;3.16 mm, width of posterior part 1.72&ndash;2.16 mm (n=20). Overall body shape eruciform (Fig. 17), total length without case 10.17&ndash;11.06 mm (n=20).&lt;/p&gt; &lt;p&gt;Head&lt;/p&gt; &lt;p&gt; Head capsule hypognathous, ellipsoidal, with width 1.37&ndash;1.48 mm (n=20) (Figs 17&ndash;18, 22). Head brown, dorsally darker and laterally lighter (Figs 16&ndash;17), with granular surface sculpturing surface (Fig. 19). Genae of the parietals reddish-brown to yellow with lighter ring around each eye (Fig. 18). Posterior part of dorsum with numerous, dark muscle attachment spots. Distinct area of spinules (small spines, size approximately 0.015&ndash;0.025 mm) positioned laterally on each side of head capsule next to the eye (Figs 20&ndash;21). Spinules also in some specimens on posterior part of each antennal prominence. Frontoclypeal apotome bell-shaped with narrow central region (Fig. 22). Antennae short, brown to dark brown, each positioned on small, noticeable prominences accompanied by 2 prominent lateral setae (setae no. 7 and no. 9) (Figs. 18&ndash;19). Other primary setae positioned as shown in Fig. 22 and light or dark and short or long as described for &lt;i&gt;D&lt;/i&gt;. &lt;i&gt;ramae&lt;/i&gt;.&lt;/p&gt; &lt;p&gt;Labrum symmetrical, brown posteriorly to yellowish anteriorly, with setal brush at anterolateral margins and 5 pairs of thin primary setae on dorsal surface.&lt;/p&gt; &lt;p&gt;Mandibles black, mesal part reddish. Typical for grazers, mesal margin with setal brush and without teeth except 1 small tooth usually present subapically (Fig. 23). Two setae present laterobasally on each mandible (Fig. 23).&lt;/p&gt; &lt;p&gt;Labium and maxillae light-brown (yellowish). Maxillary palps 5-segmented.&lt;/p&gt; &lt;p&gt;Thorax&lt;/p&gt; &lt;p&gt;Pronotum dark brown to black (Figs 16&ndash;18) with granular surface sculpturing (Figs 24&ndash;25). Posterior margin rounded, both posterior and lateral margins thick and darkly sclerotized (Fig. 18). Anterior part (i.e. 50&ndash;60 %) of pronotum slightly concave, posterior part with a prominent median hump (Figs 18, 24). Pronotum bearing dark setae, especially laterally and on anterior margin, some of them long and conspicuous (Figs 18, 24). Dorsal and lateral regions of pronotum covered with numerous white recumbent setae (Figs 24- 25). Prosternal horn present.&lt;/p&gt; &lt;p&gt; Mesonotum sclerites brown, lighter than pronotum, with dark muscle attachment spots and uneven (rugged) surface. Long, dark setae at positions &lt;i&gt;sa&lt;/i&gt; 1, &lt;i&gt;sa&lt;/i&gt; 2 and &lt;i&gt;sa&lt;/i&gt; 3 (Fig. 26). Posterior and lateral margins thick and darkly sclerotized.&lt;/p&gt; &lt;p&gt; Metanotum with 3 pairs of dorsal sclerites (Fig. 26). Anteromedian (&lt;i&gt;sa&lt;/i&gt; 1) sclerites ellipsoid, with distance between them smaller than their length (Figs 26, 48&ndash;49), covered by setae, mainly anteromedially, color similar to mesonotum. Posteromedian (&lt;i&gt;sa&lt;/i&gt; 2) sclerites smaller and lighter than &lt;i&gt;sa&lt;/i&gt; 1 sclerites (Figs 26, 48&ndash;49), diagonally and irregularly ellipsoid and with many dark setae. Group of setae present on membranes between &lt;i&gt;sa&lt;/i&gt; 2 sclerites and between &lt;i&gt;sa&lt;/i&gt; 2 and &lt;i&gt;sa&lt;/i&gt; 3 sclerites. Lateral (&lt;i&gt;sa&lt;/i&gt; 3) sclerites longitudinally prolonged, sickleshaped, lighter brown with dark median region, and group of setae anteriorly (Fig. 26).&lt;/p&gt; &lt;p&gt;Legs yellow-brown to dark brown or black, with dark ventral and dorsal margins (Figs 16&ndash;18). Foreleg coxae with dark setae on ventral and dorsal edges. Foreleg trochanters without dorsal setae, each with few light-yellow setae on ventral margin and distally with dense ros of short, fine, yellowish setae (trochanteral brush) continuing onto basoventral margin of femur (Fig. 27). Foreleg femora each with dark setae on dorsal edge, few stout, light-yellow setae on ventral margin in addition to basoventral dense row of short, fine, yellowish setae (Fig. 27). Mid- and hind leg coxae and femora with dark setae on both ventral and dorsal edges, midleg trochanters with few, fine, yellowish setae apicoventrally (Figs 28&ndash;29). Additional setae present on anterior and posterior faces of all femora. Setae on dorsal edges of tibiae present only distally in all legs. Tarsae each with claw and basal seta, and tibial spurs light brown, almost yellowish. Foreleg coxae and femora wide compared to those of mid- and hind legs (Figs 27&ndash;29). Mid- and hind-legs similar in shape and size (Figs 28&ndash;29), with slender coxae, trochanters, and femora.&lt;/p&gt; &lt;p&gt;Abdomen&lt;/p&gt; &lt;p&gt; Abdominal segment I with well-developed dorsal and lateral humps (protuberances). Numerous setae present anterior and lateral to dorsal hump. It is not possible to distinguish between setal areas &lt;i&gt;sa&lt;/i&gt; 1 and &lt;i&gt;sa&lt;/i&gt; 2 on dorsal side. With numerous ventral setae, some of them with small sclerites at bases. Lateral humps with few setae.&lt;/p&gt; &lt;p&gt;Single filamentous gills (Fig. 17) present on segments II&ndash;VII (Fig. 30). Dorsal pre- and post-segmental gills present on segments II&ndash;VI; ventral pre- and post-segmental gills present on segments II&ndash;VII. Lateral presegmental gills present on segments III&ndash;IV and lateral post-segmental gills on segments II&ndash;IV (Fig. 30). In some specimens dorsal pre-segmental gills on segment VI, post-segmental gills on segments V and VI, and lateral pre- and post-segmental gills on segment IV are not present (Fig. 30). Number of dorsal setae on abdominal segment VIII varies (2&ndash;6). Lateral fringe extends from last third of segment II to first half of segment VIII; in some specimens, only few setae forming lateral fringe on segment II or setae not visible.&lt;/p&gt; &lt;p&gt;Segment IX bearing irregular, semicircular, light brown dorsal sclerite, generally with 8 long, dark setae on posterior margin and several shorter, light setae on posterior half of sclerite (Fig. 31). Anal prolegs typical of limnephilids (Fig. 32), each with lateral sclerite longitudinally prolonged, sickle-shaped, yellowish, with small setae scattered over posterior 2/3rds and 2 large, dark setae at posterior end (Fig. 32). Anal claws brown.&lt;/p&gt;Published as part of &lt;i&gt;Posilović, Hrvoje, 2010, Description of the larvae of Drusus ramae Marinković- Gospodnetić and Drusus medianus Marinković- Gospodnetić (Trichoptera: Limnephilidae) with some genetic, distributional, ecological, faunal and conservation notes, pp. 1-24 in Zootaxa 2484&lt;/i&gt; on pages 8-12, DOI: &lt;a href="http://zenodo.org/record/1051908"&gt;10.5281/zenodo.1051908&lt;/a&gt

FIGURES 41–45. 41 in Description of the larvae of Drusus ramae Marinković- Gospodnetić and Drusus medianus Marinković- Gospodnetić (Trichoptera: Limnephilidae) with some genetic, distributional, ecological, faunal and conservation notes

FIGURES 41–45. 41, Drusus croaticus Marinković-Gospodnetić, 1971: pronotum, right lateral view; 42, Drusus ramae Marinković-Gospodnetić, 1971: pronotum, right lateral view; 43, Drusus medianus Marinković-Gospodnetić, 1976: pronotum, right lateral view; 44, D. radovanovici septentrionis Marinković-Gospodnetić, 1976: pronotum, right lateral view; 45, Drusus medianus Marinković-Gospodnetić, 1976 (left), and D. radovanovici septentrionis Marinković- Gospodnetić, 1976 (right): parietal part of the head at eye level showing spinules, right lateral view

Identification of biogenetic calcite and aragonite using SEM

Identification of calcite and aragonite is very important for studying different fossil or recent biomineralized skeletons. Problem occurs when scanning electron microscopy is used for studying calcite and aragonite present in the same part of skeleton. The same chemical composition of these two minerals produces the same contrast on SEM images. There are three possible ways how to distinguish calcite and aragonite in such mixture. (1) It is possible to recognize the crystal habits of these two minerals, if the crystal faces are developed. (2) Geochemical difference could be also important tool for distinguishing aragonite (containing large cations like Sr, Ba, or Pb) from calcite (containing small cations like Mg, Mn, Fe, Zn, or Ni). However, it is also possible that large cations remain in calcite crystal structure after phase transformation from aragonite to calcite. (3) Last possibility in distinguishing calcite from aragonite is to use staining methods. There were different staining methods used for SEM analyses with different success. SUZUKI et al. (1993) successfully used Meigen’s staining method, but results provided by Feigl’s staining method were unsatisfactory. Failure of using Feigl’s staining method was caused by erroneous applying of used solutions

Mineralogical and geomicrobiological investigation of phosphorite from Ervenik, Croatia

Phosphate minerals hydroxylapatite, fluorapatite and crandallite were identified in nodules within phosphorites from Ervenik, Croatia. The minerals were identified using optical microscopy, XRD, SEM and EDX analyses. The presence of fungi was recognized only in association with phosphate-rich phases. Fungal activity resulted in the dissolution of apatite, producing hollow crystals, particularly in hydroxylapatite – enriched zones. A substantial number of hyphae were observed on the surface of phosphate minerals, in addition to saprophytic bacteria and bacterial spores. Induced activity of phosphate-accumulating bacteria in an aquatic environment caused dissolution of the phosphate minerals. The aqueous phase contained increased concentrations of several  elements, including Ca, Sb, U, V and As. These elements are important constituents of  minerals of the apatite group. As a consequence of the crystallization of apatite, the concentration of phosphate decreases with a corresponding increase in aluminium concentration, resulting in the prevalence of crandallite as the stable phase, forming the outer sector of the spherulites.  </p

Mineralogical and geomicrobiological investigation of phosphorite from Ervenik, Croatia

Phosphate minerals hydroxylapatite, fluorapatite and crandallite were identified in nodules within phosphorites from Ervenik, Croatia. The minerals were identified using optical microscopy, XRD, SEM and EDX analyses. The presence of fungi was recognized only in association with phosphate-rich phases. Fungal activity resulted in the dissolution of apatite, producing hollow crystals, particularly in hydroxylapatite – enriched zones. A substantial number of hyphae were observed on the surface of phosphate minerals, in addition to saprophytic bacteria and bacterial spores. Induced activity of phosphate-accumulating bacteria in an aquatic environment caused dissolution of the phosphate minerals. The aqueous phase contained increased concentrations of several  elements, including Ca, Sb, U, V and As. These elements are important constituents of  minerals of the apatite group. As a consequence of the crystallization of apatite, the concentration of phosphate decreases with a corresponding increase in aluminium concentration, resulting in the prevalence of crandallite as the stable phase, forming the outer sector of the spherulites.  </p