828 research outputs found

    Diagnosis of central venous catheter-related thrombus by transesophageal echocardiography

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    Application of the resonant recognition model to analysis of interaction between viral and tumor suppressor proteins

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    Recent findings in cancer research has established a connection between a T-antigen - common virus - and a brain tumor in children. The studies suggested the T-antigen, the viral component of a specific virus, called the JC virus, plays a significant role in the development of the most frequent type of malignant brain tumors by blocking the functionality of tumor suppressor proteins such as p53 and pRb. Here we have investigated the structure and function relationships of T-antigen, p53 and pRb proteins using the Resonant Recognition Model (RRM), a physico-mathematical approach based on digital signal processing methods

    Evaluating Productivity of Small-Scale Cable Yarding System Integrated with a Portable Winch

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    Small-scale forestry operations, which are used in non-industrial and site specific forestry, provide alternative logging methods suitable for precision forestry approach. In this study, a small-scale cable yarding system integrated with a portable winch was considered as alternative timber extraction method compared to a standard tower yarder. It was aimed to evaluate productivity of this yarding method, which was implemented during commercial harvesting activities performed in a 10.74 ha black pine stand located in Bursa province of Turkey. The main factors (i.e. slope, yarding distance, lateral pulling distance, log volume, log length), significantly affecting the productivity, were evaluated based on two slope classes (34–50% and 50–70%) and two yarding distances (100 m and 200 m). The results indicated that the average productivity was 0.95 m3/PMH and 0.90 m3/SMH. It was revealed that the productivity of the small-scale cable yarding decreased as the ground slope and the yarding distance increased. Statistical analysis indicated that there was a significant (p<0.001) relationship between productivity and log volume and length in four applications. On the other hand, it was found that there was a significant (p<0.05) relationship between productivity and lateral pulling distance in only the first application (34–50% slope; 100 m yarding distance). Considering the volume classes of the logs, it was determined that the productivity increased from the low volume class to the high volume class

    The Evolution of Computer-Aided Road Design Systems

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    In order to locate a path between two known locations on a ground surface, a large number of alternative paths should be evaluated considering physical, economical, and environmental factors. Optimization techniques can be used to search for a path that minimizes the total costs while satisfying the design and environmental constraints. These techniques can result in considerable time savings in forest road design. Initially, these optimization techniques have been applied to highway design and recently, they have been applied to forest road design. This paper describes the evolution of the optimal route location systems used in both highway and forest road design based on ten criteria. The paper concludes by describing some of the unsolved problems in forest road design

    Procjena produktivnosti alternativnih metoda koranja drvnog sortimenta

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    In Turkey, timber debarking stages are generally carried out by using axes. However, this method takes a lot of time and requires more work forces. In addition, since leaving residual trees with bark in stands increases the risk of insect damages, residual trees require quick barking process. In recent years, chainsaw mounted debarking tools have been widely used in debarking stages due to performing jobs quicker with less labor force. In this study, two different debarking methods including using axes and debarking tool were analyzed by considering operation productivity. The field studies were conducted in Brutian Pine (Pinus brutia Ten.) stand located in Bahçe Forest Enterprise Chief of Osmaniye Forest Enterprise Directorate in Adana Regional Forestry Directorate. As a result of study, the productivity of chainsaw mounted debarking tool was found to be five times higher than that of using axes for debarking. Thus, use of chainsaw mounted debarking tool is better alternative than use of axe in debarking activities, as it takes less time and minimize physical work load of the loggers.U Turskoj se faze koranja drveta obično obavljaju uz pomoć sjekira. Međutim, ta metoda zahtijeva puno vremena i puno radne snage. Uz to, budući da ostavljanje drveta s korom u sastojinama povećava rizik od oštećenja insektima, zahtijeva hitan proces guljenja kore. Posljednjih godina puno se koriste guljači kore koji se montiraju na motornu pilu, budući da se posao obavlja brže s manjim brojem radne snage. U ovoj studiji, analizirane su dvije različite metode koranja u razmatranju produktivnosti rada koje uključuju uporabu sjekira i guljač kore koji se montira na motornu pilu. Terenske studije provedene su u sastojini brucijskog bora (Pinus brutia Ten.) koja se nalazi u Upravi šuma Bahçe u regionalnom šumskom gospodarstvu Adane. Rezultat studije bio je da je produktivnost pila za koranje bila pet puta veća od uporabe sjekira za koranje. Tako je guljač kore koji se montira na motornu pilu bolja alternativa od uporabe sjekire u guljenju kore, budući da je kod njega potrebno manje vremena te smanjuje fizički rad drvosječa

    Investigation of the structural and functional relationships of oneogene proteins

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    Proteins are the biomolecular workhorses driving the most biological processes in any living organism. These processes are based on selective interactions between particular proteins. So far, the rules governing the coding of the protein&#039;s biological function, i.e. its ability to selectively interact with other biomolecules, have not been elucidated. The resonant recognition model (RRM) is a novel physicomathematical approach established to analyze the interaction between a protein and its target. The RRM assumes that the specificities of protein interactions are based on the resonant electromagnetic energy transfer at the specific frequency for each interaction. One of the main applications of this model is to predict the location of a protein&#039;s biological active site(s) using digital signal processing. This paper incorporates the continuous wavelet transform (CWT) into the RRM to predict the active sites, for a chosen protein example. We have investigated the oncogene functional group using digital signal analysis methods, in particular Fourier transform and CWT; determined oncogenes&#039; characteristic frequency and functional active sites; and performed the design of the peptide analogous. The results obtained provide new insights into the structure-function relationships of the analyzed oncogene protein family

    Korištenje GIS tehnika za modeliranje širenja antropogene buke koju stvara motorna pila prilikom sječe šuma

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    Noise is an environmental pollution that negatively affects human health and reduces the performance of employees. Forest harvesting activities are one of the working environments where noise effect is intense. The most common equipment used in forest operations is chainsaw whose noise affects not only the operator but also the wildlife in the territory. The noise maps showing noise propagation can be effectively used in evaluating and controlling the noise effects. In this study, it was aimed to measure the anthropogenic noise levels &#8203;&#8203;resulting from the chainsaw used in tree felling and to map its noise propagation with SPreAD-GIS (System for Prediction of Acoustic Detectability) which is a GIS (Geographical Information Systems) based noise prediction software. The study was conducted in Karacabey Flooded Forest within the city of Bursa in Türkiye. The results indicated that the average noise level from the chainsaw was above the danger limit (90 dBA) that causes increased physiological reactions and headache on the workers. According to the noise propagation map, the noise exposure of the employees exceeded the warning limit (85 dBA) and the maximum noise level was 95.96 dBA during the harvesting activity. In some parts of the study area, the noise level was 45 dBA or above, causing negative effects on bird species. It can be concluded that the noise maps can be effectively used to determine noise propagation generated by a chainsaw and evaluate the noise effects on the operators and as well as on the bird species in the perimeter.Buka je onečišćenje okoliša koje negativno utječe na zdravlje ljudi i smanjuje učinak zaposlenika. Aktivnosti sječe šuma jedno su od radnih okruženja u kojima je buka intenzivna. Najčešća oprema koja se koristi u šumarstvu je motorna pila, čija buka utječe ne samo na operatera, već i na divlje životinje na teritoriju. Karte buke koje prikazuju širenje buke mogu se učinkovito koristiti za procjenu i kontrolu učinaka buke. U ovome radu cilj je bio izmjeriti razine antropogene buke nastale radom motorne pile koja se koristi pri sječi stabala i mapirati širenje buke pomoću SPreAD-GIS programa (Sustav za predviđanje akustične detektabilnosti) čija se procjena širenja buke temelji na GIS-u (Geografski informacijski sustav). Istraživanje je provedeno u poplavnoj šumi Karacabey na području grada Bursa u Turskoj. Rezultati su pokazali da je prosječna razina buke motorne pile iznad granice opasnosti (90 dBA), što uzrokuje pojačane fiziološke reakcije i glavobolju radnika. Prema karti širenja buke, izloženost zaposlenika buci prešla je granicu upozorenja (85 dBA), a maksimalna razina buke tijekom rada iznosila je 95,96 dBA. U nekim dijelovima istraživanog područja razina buke iznosila je 45 dBA ili više, što je uzrokovalo negativan utjecaj na vrste ptica. Može se zaključiti da se karte buke mogu učinkovito koristiti za određivanje širenja buke koju stvara motorna pila i procjenu učinaka buke na operatere, kao i na vrste ptica u okruženju

    Procjena aktivnosti sanacijske sječe nakon požara u mediteranskom području Turske

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    Various problems such as massive volume loss, erosion, degradation of water resources, and air pollution emerge after forest fire incidents. Thus, necessary forest operations should be quickly planned and implemented after forest fires so that afforestation activities can take place immediately to maintain forest vegetation in burned areas. The aim of this study was developing a Post-fire Action Planning (PFAP) model to minimize the time spent on salvage logging activities. PFAP model will assist decision makers for removing salvage timber in a timely manner after large scale forest fires, while considering economic and environmental constraints, and dealing with available employment conditions in local forest industry. The capabilities of this model were examined by standardizing the operational planning and developing a fast decision-making process. The model was implemented in Taşağıl Forest Enterprise Chiefs (FEC) of Antalya Forest Regional Directorate where the forests are sensitivity to fire at the first degree level and the second largest forest fire in the history of Turkish Forestry occurred in this area in 2008. The findings of PFAP model were compared with the data of actual salvage logging operation obtained from the FEC. The results indicated that using operational planning based PFAP model is capable of reducing total time spent on salvage logging operation by about 60%. Based on the forestry compartments of the study area, estimated durations of salvage logging operations were 15 to 75 days less than that of actual operations taken place in the field. Therefore, it is highly anticipated that using operational planning based PFAP model has great potential to provide economically and environmentally sound forest operations after forest fires.Nakon šumskih požara nastaju različiti problemi, kao što je velik gubitak drvne mase, erozije tla, degradacija pitkih izvora vode te onečišćenje zraka. Neophodno je kvalitetno i učinkovito isplanirati i implementirati potrebne šumske operacije nakon šumskog požara, kako bi se odmah moglo započeti s pošumljavanjem u svrhu održanja šumske vegetacije u izgorenim područjima. Cilj ovoga istraživanja je bio razvoj modela planiranja aktivnosti nakon požara, kako bi se smanjilo vrijeme utrošeno na aktivnosti sanitarne sječe. Model planiranja aktivnosti nakon požara pomoći će donositeljima odluka u pravovremenom uklanjanju saniranih debla nakon velikih šumskih požara, uzimajući u obzir ekonomska i ekološka ograničenja te rješavajući mogućnost zapošljavanja u lokalnoj drvnoj industriji. Mogućnosti ovoga modela provjerene su pomoću standardizacije operativnog planiranja i razvoja procesa brzog donošenja odluka. Model je implementiran u šumariji Taşağıl Regionalne uprave za šume Antalya, gdje su šume svrstane u prvi stupanj opasnosti od požara te se drugi najveći šumski požar u povijesti Turske uprave za šume dogodio upravo na ovome području 2008. godine. Rezultati ovoga modela uspoređeni su s podatcima stvarnih sanacijskih sječa dobivenih od šumarija. Rezultati su pokazali da se korištenjem operativnog planiranja temeljem modela planiranja aktivnosti nakon požara može smanjiti ukupno vrijeme utrošeno na sanacijske sječe za 60%. S obzirom na različite šumske odjeljke u istraživanome području, procijenjeno trajanje sanacijske sječe bilo je 15 do 75 dana kraće od stvarnih operacija na terenu. Prema tome, očekuje se da korištenje operativnog planiranja temeljem modela planiranja aktivnosti nakon požara ima velik potencijal u osiguravanju ekonomski i ekološki korisnih šumskih radova nakon šumskih požara

    A Comparison of Two Felling Techniques Considering Stump-Height-Related Timber Value Loss

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    Harvest from plantations can provide both industrial wood and forest residues for bioenergy, including stumps. The literature suggests that the choice of cutting system can affect the division between industrial wood recovery and remaining stump volume. In this study, two felling techniques - motor-manual chainsaw and feller-buncher, were compared based on stump-height-related timber value loss for four ground slope classes: high, medium, low, and flat. The economic value loss of wood material for three products - sawlogs, pulpwood, and fiber-chip wood, was determined based on the estimated volume of stumps left in the woods. The results indicated that the average stump height for the motor-manual chainsaw and fellerbuncher was 17.16 cm and 8.69 cm. The economic value loss of wood material per stump was higher in felling by manual chainsaw as compared to the feller-buncher operation (log: €0.60↑, paper wood: €0.29↑, fiber-chip: €0.15↑). However, volume loss due to high stumps could contribute to wood for bioenergy if stumps are subsequently removed. Additional research is needed to evaluate the benefits and costs of stump removal for bioenergy as part of a total supply chain to provide both industrial wood and wood for bioenergy
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