EKSPLOATACIJA KREMENOG PIJESKA NA POVRŠINSKOM KOPU "VRTLINSKA" (MOSLAVINA, HRVATSKA)

The exploitation of glass sand in Slavonia and Moslavina has a long tradition. The open-pit »Vrtlinska« is-accordirtg to its dimensions and production capacity the biggest one in this regions. Exploitation reserves within this open pit amount about) 1 000 000 t glass sand of a very good quality, and the production capacity is 200 000 t yearly according to real needs during design and opening the pit, i. e. before the war. This article discusses geological and geomechanical characteristics of the deposit, as well as the exploitation process, which is considerably matching natural characteristics of the deposit. A more detailed description is given of the planned exploitation phase I above groundwater level which is carried out according to discontinuous system. For the exploitation of the depth part under groundwater level in the phase II, the necessity of further examination of hydrogeological characteristics of the deposit is presented, in order to acquire necessary information on groundwater regime and drainage conditions. Such knowledge will influence the choice of the most appropriate solutions in the exploitation of the depth part of the deposit.Eksploatacija kremenog pijeska u Slavoniji i Moslavini ima dugu tradiciju. Površinski kop »Vrtlinska« prema veličini i kapacitetu proizvodnje najveći je u ovim područjima. Eksploata-cijske rezerve u granicama ovog površinskog kopa iznose približno 1 1 000 000 tona kremenog pijeska vrlo dobre kvalitete, a kapacitet proizvodnje planiran je 200 000 t/god. prema realnim potrebama u vrijeme izrade projekta i otvaranja kopa, tj. prije rata. U članku su prikazane geološke i geomehaničke značajke ležišta, te tehnološki proces eksploatacije, koji je u velikom dijelu usklađen s njegovim prirodnim karakteristikama. Detaljnije je obrađena projektirana eksploatacija I. faze iznad razine podzemne vode, koja se izvodi prema diskontinu-alnom sustavu. Za eksploataciju dubinskog dijela ispod razine podzemne vode u II. fazi navedena je potreba detaljnijeg istraživanja hidrogeoloških karakteristika ležišta, u cilju stjecanja nužnih podataka o režimu podzemne vode i uvjetima odvodnjavanja. Takva saznanja utjecat će na izbor najpovoljnijih tehnoloških rješenja i eksploatacije dubinskog dijela ležišta

EKSPLOATACIJA KREMENOG PIJESKA NA POVRŠINSKOM KOPU "VRTLINSKA" (MOSLAVINA, HRVATSKA)

The exploitation of glass sand in Slavonia and Moslavina has a long tradition. The open-pit »Vrtlinska« is-accordirtg to its dimensions and production capacity the biggest one in this regions. Exploitation reserves within this open pit amount about) 1 000 000 t glass sand of a very good quality, and the production capacity is 200 000 t yearly according to real needs during design and opening the pit, i. e. before the war. This article discusses geological and geomechanical characteristics of the deposit, as well as the exploitation process, which is considerably matching natural characteristics of the deposit. A more detailed description is given of the planned exploitation phase I above groundwater level which is carried out according to discontinuous system. For the exploitation of the depth part under groundwater level in the phase II, the necessity of further examination of hydrogeological characteristics of the deposit is presented, in order to acquire necessary information on groundwater regime and drainage conditions. Such knowledge will influence the choice of the most appropriate solutions in the exploitation of the depth part of the deposit.Eksploatacija kremenog pijeska u Slavoniji i Moslavini ima dugu tradiciju. Površinski kop »Vrtlinska« prema veličini i kapacitetu proizvodnje najveći je u ovim područjima. Eksploata-cijske rezerve u granicama ovog površinskog kopa iznose približno 1 1 000 000 tona kremenog pijeska vrlo dobre kvalitete, a kapacitet proizvodnje planiran je 200 000 t/god. prema realnim potrebama u vrijeme izrade projekta i otvaranja kopa, tj. prije rata. U članku su prikazane geološke i geomehaničke značajke ležišta, te tehnološki proces eksploatacije, koji je u velikom dijelu usklađen s njegovim prirodnim karakteristikama. Detaljnije je obrađena projektirana eksploatacija I. faze iznad razine podzemne vode, koja se izvodi prema diskontinu-alnom sustavu. Za eksploataciju dubinskog dijela ispod razine podzemne vode u II. fazi navedena je potreba detaljnijeg istraživanja hidrogeoloških karakteristika ležišta, u cilju stjecanja nužnih podataka o režimu podzemne vode i uvjetima odvodnjavanja. Takva saznanja utjecat će na izbor najpovoljnijih tehnoloških rješenja i eksploatacije dubinskog dijela ležišta

IMPROVMENT OF THE MINING METHOD IN THE BAUXITE MINE ĆUKOVAC-GRIŽINICA

Eksploatacija boksita u Dalmaciji ima dugu tradiciju. Najveća jama ovog boksitonosnog područja razvila se u ležištima Ćukovac i Grižinica, a eksploatacijske rezerve iznose 1.180.000 tona. Godišnja proizvodnja u 1990. godini iznosila je 100.000 tona. Ova jama nalazi se u eksploataciji od 1987. godine uz primjenu klasične varijante podetažne otkopne metode sa zarušavanjem krovine. Otkopna metoda u dosadašnjem radu nije dala zadovoljavajuće rezultate gledajući na iskorištenje mineralne sirovine i rješenje tehničke zaštite. Zbog toga su predviđena istraživanja na poboljšanju postojeće otkopne metode u smislu usklađivanja prirodnih utjecaja ležišta s tehnologijom otkopavanja i karakteristikama suverene jamske mehanizacije. Rezultati istraživanja za ovu jamu ukazali su na potrebu primjene više varijanti podetažne otkopne metode, a to su: varijanta s privremenim malim komorama, varijanta s otvorenim otkopanim prostorima i varijanta sa zaštitnim slojem boksita.Exploitation of bauxite in region of Dalmatia has tradition of more than 50 years. The biggest underground mine of this bauxite hearing area was developed in deposit Ćukovac-Grižinica with proved workable reserves of 1.2 x 106 t. Yearly output in 1990. was 100.000 t. Production in this mine started 1987, and sublevel caving method was used. Coefficient of extraction in the parts with weak rocks is low, and unsufficient security in the conditions with firm roof. Therefore investigation of improvement of mining method was carrying on to coinside characteristics of rocks, and mining methods. Following methods were selected: sublevel caving (actually retreat stoping), sublevel sloping and sublevel caving with bauxite protection layer

POBOLJŠANJE METODE OTKOPAVANJA U LEŽIŠTIMA BOKSITA

The underground bauxite excavation in Yugoslavia is getting more important recently due to gradual exploitation of shallow deposits. The main excavation method is sublevel caving method. That technology of exploitation is characterized by high excavation loosses reaching even to 50% due to mixing of bauxite with waste. By beds with competent limestone roof which are not liable to direct caving are formed unplanned open spaces so the work safety is often dangercd by sudden caving. That was the reason for carrying out the observations in situ and investigations on mathematical models to define boundary of excavated space stability. This investigation were the basis for the new conception of further excavation of the »Jukići-Didare« mine with the application of even three exploitation methods maximally adapted to the characteristics of the remaining part of deposit.Zbog postupnog iscrpljivanja plićih ležišta, jamska proizvodnja u SFR Jugoslaviji dobiva sve više na važnosti. Podetažna otkopna metoda predstavlja osnovnu metodu. Karakteriziraju je visoki otkopni gubici i do 50% zbog miješanja boksita s jalovinom, dok se kod ležišta s čvrstom neposrednom krovinom stvaraju veliki otvoreni otkopani prostori koji zbog opasnosti od iznenadnog zarušavanja ugrožavaju sigurnost rada. Da bi se definirala granica stabilnosti takvih prostora obavljena su opažanja in situ i istraživanja na matematičkim modelima aplikacijom metode konačnih elemenata, na osnovi kojih je postavljena nova koncepcija daljnjeg otkopavanju jame Jukići-Đidare, Dalmatinskih rudnika boksita — Obrovac, uz, primjenu čak tri otkopne metode maksimalno prilagođene karakteristikama preostalog dijela ležišta

RAZVOJ EKSPLOATACIJE MINERALNIH SIROVINA ZA PROIZVODNJU CEMENTA NA POVRŠINSKIM KOPOVIMA »PARTIZAN« I »PRVOBORAC«

The article presents the exploitation of mineral raw materials for the cement industry of Split from the beginning of this century till today. Geological and geomcchanical characteristic of the open pits »Partizan« and "Prvoborac«, located within the same deposit and the technological exploitation process with basic parameters of suecessibility in both pits arc detaily discussed. The works of open pits\u27 reclamation which has to be carried out simultanouslly with the exploitation itself arc also considered, as well as the perspectives of further exploitation development, in accord with modern tendencies to the mining technology developmentU članku je iznesen prikaz eksploatacije mineralnih sirovina za cementnu industriju Splita, od početka ovog stoljeća do danas, Dataljnije su obrađene geološke i geomehaničke karakteristike kopova »Partizan« i »Prvoborac« koji se nalaze unutar istog ležišta, te tehnološki proces eksploatacije s osnovnim pokazateljima uspješnosti na oba kopa. Također, prikazani su radovi na sanaciji kopova, koju je potrebno provoditi paralelno sa samom eksploatacijom. Konačno, prikazane su perspektive daljnjeg razvoja eksploatacije u skladu sa suvremenim tendencijama razvoja rudarske tehnologij

RISK FACTORS AND BONE MINERAL DENSITY IN ATHLETES AND NON-ATHLETES

Risk factors are important aspects in the treatment of patients with lower bone mineral density (BMD).The objective of this study was to estimate the association between risk factors and BMD status of subjects.Forty subjects - athletes of first sub-sample, were recruited from a football club “Železničar” in Niš, while forty subjects - non-athletes of the second sub-sample, were recruited from the Faculty of Occupational Safety in Niš, totally 80 subjects of masculine sex. BMD was diagnosed by using Dual X-Ray Energy Absorptiometry (DEXA densitometer), in the lumbar region of the spinal column and region of the hip articulation, while the presence of risk factors was evaluated by the One-Minute Osteoporosis Risk Test, ie. questionnaire of the International Osteoporosis Foundation, just before the diagnostics of BMD. All subjects agreed with the terms of research, conducted in accordance with the Declaration of Helsinki.Among 80 subjects, in six (1 athlete and 5 non-athletes) athletes osteopenia was found in the lumbar region of the spinal column, and in three (non-athletes) osteopenia was found in the region of hip articulation. Based on the results of χ2 test, there was the association between the lack of physical activity as a risk factor and osteopenia in the lumbar region of the spinal column (BMDSPINE osteopenia), and between the lack of physical activity as a risk factor and osteopenia in the region of hip articulation (BMDHIP osteopenia), while the association significance between smoking as a risk factor and BMDSPINE osteopenia should be taken with caution, because it is approaching the critical value (p=0.056).Concerning this research, the risk factors had a considerably greater impact on low BMD in non-athletes, compared to athletes, ie., in patients who are smokers and lack physical activity

THE IMPROVEMENT OF THE EXCAVATION METHODS IN BAUXITE DEPOSITS

The underground bauxite excavation in Yugoslavia is getting more important recently due to gradual exploitation of shallow deposits. The main excavation method is sublevel caving method. That technology of exploitation is characterized by high excavation loosses reaching even to 50% due to mixing of bauxite with waste. By beds with competent limestone roof which are not liable to direct caving are formed unplanned open spaces so the work safety is often dangercd by sudden caving. That was the reason for carrying out the observations in situ and investigations on mathematical models to define boundary of excavated space stability. This investigation were the basis for the new conception of further excavation of the »Jukići-Didare« mine with the application of even three exploitation methods maximally adapted to the characteristics of the remaining part of deposit

Neuroendocrine breast carcinoma metastatic to renal cell carcinoma and ipsilateral adrenal gland

We report on a 60-year-old woman with neuroendocrine carcinoma of the left breast metastasizing to renal cell carcinoma (RCC) of the left kidney and to adrenal gland. A yellow, well-circumscribed tumor, 11 cm in largest diameter and limited to the kidney, was found. Histopathology revealed RCC with foci of neuroendocrine differentiation. Solid sheets of hyperchromatic epithelioid cells with high mitotic activity were found between typical clear cells of RCC. These cells were CAM5,2 and E-cadherin focally positive, synaptophysin and NSE weakly positive, CK19 moderately positive, and AE1-AE3 and EMA strongly positive. Chromogranin A, CD10, CK 14, CK 20, HER2 (score 1+), vimentin, and HMB45 were negative. The left adrenal gland contained multiple, separate foci of a tumor composed of neuroendocrine components. Because of the biphasic tumor in the kidney, extensive clinical examination and further analyses were recommended. Tumor in the left breast was revealed. Two months later, the patient underwent mastectomy with axillary lymph node dissection. The tumor was histologically and immunohistochemically similar to the neuroendocrine component within RCC. All axillary nodes were positive. To our knowledge, this is the first case of neuroendocrine breast carcinoma with metastasis to renal cell carcinoma and ipsilateral adrenal gland

CALCANEAL MINERAL DENSITY IN CHILDREN ATHLETES AND TAKE-OFF LEG

It is well-known that physical activity has an anabolic effect on the bone tissue. To examine the influence of the take-off lower limb to the bone density we studied a group of prepubertal boys and girls at the initial phase of their peak bone mass acquisition. A sample consisted of 60 subjects ie., 32 soccer players (boys, 10.7±0.5 years old) and 28 swimmers (15 girls and 13 boys, 10.8±0.8 years old), who had performed at least one year of high-level sport training (10-15 hours per week for soccer players, 8-12 hours per week for swimmers). The sample was divided into two groups: the first consisted of 40 subjects, with the left take-off leg, while the second consisted of 20 subjects, with the right take-off leg. The bone mineral density (BMD) measurements of the left and the right calcaneus were performed using ultrasound densitometer “Sahara” (Hologic, Inc., MA, USA). There were no significant differences between the groups in regard to BUA and SOS of both the left and the right take-off lower legs. Mean BUA of the take-off left leg and the take-off right leg were different, but not significantly (p>0.05). Likewise, mean SOS of the take-off left leg and the take-off right leg were different, but it was not significant (p>0.05). The results do not indicate that the take-off lower limb has an influence on calcaneal bone mineral density