bluuebunny/crossref_metadata_2025 huggingface dataset:
Dispersal pathways, seed rains, and the dynamics of larval behavior
Authors: Zimmer Richard K. , Fingerut Jonathan T. , Zimmer Cheryl Ann
Published: July 2009

Dispersing propagules (larvae, seeds, and spores) establish and maintain populations, which serve as templates for subsequent species interactions. Connectivity among demes derives, in large part, from connectivity between consecutive steps, release, transport, and settlement, in dispersal pathways. Concurrent measurements of individuals in each step are a necessary precursor to identifying governing mechanisms. Here we directly and definitively resolved the roles of physics and behavior in mediating dispersal pathways of an estuarine parasite between its intermediate hosts. Planktonic cercariae of Himasthla rhigedana, a parasitic flatworm, are functionally similar to lecithotrophic larvae of many free‐living marine invertebrates. The combination of parasite life cycle characteristics and the relatively simple tidal flows in their habitat renders this system an effective model for dispersal studies.

Simultaneous field measurements of larval release, transport, settlement, and the flow regime, together with mechanistic experiments, led to empirical understanding of host colonization. All dispersal steps were highly and significantly correlated over time and in space. This tight coupling resulted, unequivocally, from a suite of larval behaviors. Cercariae emerged from first intermediate host snails only during daytime flood tides, enhancing larval retention in the marsh. Daylight triggered downward swimming, and within seconds, cercariae overpowered turbulent mixing, landing in benthic habitat of second intermediate host snails and crabs. Larvae settled (encysted) on external regions of snails/crabs that, presumably, were most vulnerable to ingestion by definitive host shorebirds. In total, cercarial behaviors greatly foreshortened dispersal distances, magnified local parasite prevalence, and increased the likelihood of large‐scale transmission by definitive hosts. Cracking open the black box of dispersal thus revealed mechanisms, connectivity, and ecological consequences of the larval stage.
Linking sediment‐charcoal records and ecological modeling to understand causes of fire‐regime change in boreal forests
Authors: Brubaker Linda B. , Higuera Philip E. , Rupp T. Scott , Olson Mark A. , Anderson Patricia M. , Hu Feng Sheng
Published: July 2009

Interactions between vegetation and fire have the potential to overshadow direct effects of climate change on fire regimes in boreal forests of North America. We develop methods to compare sediment‐charcoal records with fire regimes simulated by an ecological model, ALFRESCO (Alaskan Frame‐based Ecosystem Code) and apply these methods to evaluate potential causes of a mid‐Holocene fire‐regime shift in boreal forests of the south‐central Brooks Range, Alaska, USA. Fire‐return intervals (FRIs, number of years between fires) are estimated over the past 7000 calibrated 14C years (7–0 kyr BP [before present]) from short‐term variations in charcoal accumulation rates (CHARs) at three lakes, and an index of area burned is inferred from long‐term CHARs at these sites. ALFRESCO simulations of FRIs and annual area burned are based on prescribed vegetation and climate for 7–5 kyr BP and 5–0 kyr BP, inferred from pollen and stomata records and qualitative paleoclimate proxies. Two sets of experiments examine potential causes of increased burning between 7–5 and 5–0 kyr BP. (1) Static‐vegetation scenarios: white spruce dominates with static mean temperature and total precipitation of the growing season for 7–0 kyr BP or with decreased temperature and/or increased precipitation for 5–0 kyr BP. (2) Changed‐vegetation scenarios: black spruce dominates 5–0 kyr BP, with static temperature and precipitation or decreased temperature and/or increased precipitation. Median FRIs decreased between 7–5 and 5–0 kyr BP in empirical data and changed‐vegetation scenarios but remained relatively constant in static‐vegetation scenarios. Median empirical and simulated FRIs are not statistically different for 7–5 kyr BP and for two changed‐vegetation scenarios (temperature decrease, precipitation increase) for 5–0 kyr BP. In these scenarios, cooler temperatures or increased precipitation dampened the effect of increased landscape flammability resulting from the increase in black spruce. CHAR records and all changed‐vegetation scenarios indicate long‐term increases in area burned between 7–5 and 5–0 kyr BP. The similarity of CHAR and ALFRESCO results demonstrates the compatibility of these independent data sets for investigating ecological mechanisms causing past fire‐regime changes. The finding that vegetation flammability was a major driver of Holocene fire regimes is consistent with other investigations that suggest that landscape fuel characteristics will mediate the direct effects of future climate change on boreal fire regimes.
A geographic mosaic of genetic variation within a foundation tree species and its community‐level consequences
Authors: Barbour Robert C. , O'Reilly-Wapstra Julianne M. , Little David W. De , Jordan Gregory J. , Steane Dorothy A. , Humphreys Jonathon R. , Bailey Joseph K. , Whitham Thomas G. , Potts Bradley M.
Published: July 2009

Knowledge of the manner in which genetic variation within a tree species affects associated communities and ecosystem processes across its entire range is important for understanding how geographic mosaics of genetic interactions might develop and support different communities. While numerous studies have investigated the community and ecosystem consequences of genetic variation at the hybrid cross type or genotype level within a species, none has investigated the community‐level effects of intraspecific genetic variation across the geographic range of a widespread species. This is the scale at which geographic mosaics of coevolution are hypothesized to exist. Studies at this level are particularly important for foundation tree species, which typically support numerous microbial, fungal, plant, and animal communities. We studied genetic variation across eight geographical races of the forest tree Eucalyptus globulus representing its natural distribution across southeastern Australia. The study was conducted in a 15‐year‐old common garden trial based on families derived from single‐tree open‐pollinated seed collections from the wild. Neutral molecular genetic variation within E. globulus was also assessed and compared with genetic divergence in the phenotypic and community traits. Three major findings emerged. First, we found significant genetically based, hierarchical variation in associated communities corresponding to geographical races of E. globulus and families within races. Second, divergence in foliar communities at the racial level was associated with genetically based divergence in specific leaf morphological and chemical traits that have known defensive functions. Third, significant positive correlations between canopy community dissimilarity and both neutral molecular genetic and leaf quantitative genetic dissimilarity at the race level supported a genetic similarity rule. Our results argue that genetic variation within foundation tree species has the potential to be a significant driver of the geographical mosaics of variation typical of forest communities, which could have important ecological and evolutionary implications.
The role of landscape connectivity in assembling exotic plant communities: a network analysis
Authors: Minor Emily S. , Tessel Samantha M. , Engelhardt Katharina A. M. , Lookingbill Todd R.
Published: July 2009

Landscape fragmentation and exotic species invasions are two modern‐day forces that have strong and largely irreversible effects on native diversity worldwide. The spatial arrangement of habitat fragments is critical in affecting movement of individuals through a landscape, but little is known about how invasive species respond to landscape configuration relative to native species. This information is crucial for managing the global threat of invasive species spread. Using network analysis and partial Mantel tests to control for covarying environmental conditions, we show that forest plant communities in a fragmented landscape have spatial structure that is best captured by a network representation of landscape connectivity. This spatial structure is less pronounced in invasive species and exotic species dispersed by animals. Our research suggests that invasive species can spread more easily in fragmented landscapes than native species, which may make communities more homogeneous over time.
Automatic track recognition of footprints for identifying cryptic species
Authors: Russell James C. , Hasler Nils , Klette Reinhard , Rosenhahn Bodo
Published: July 2009

The recognition of tracks plays an important role in ecological research and monitoring, and tracking tunnels are a cost‐effective method for indexing species over large areas. Traditionally, tracks are collected by a tracking system, and analysis is carried out in a manual identification procedure by experienced wildlife biologists. Unfortunately, human experts are unable to reliably distinguish tracks of morphologically similar species. We propose a new method using image analysis, which allows automatic species identification of tracks, and apply the method to identifying cryptic small‐mammal species. We demonstrate the method by identifying footprints of three invasive rat species with similar morphology that co‐occur in New Zealand, including detection of a recent invasion of a rat‐free island. Automatic footprint recognition successfully identified the species of rat for >70% of footprints, and >83% of tracking cards. With appropriate changes to the image recognition, the method could be broadly applicable to any taxa that can be tracked. Identification of tracks to species level gives better estimates of species presence and composition in communities.
Modeling utilization distributions in space and time
Authors: Keating Kim A. , Cherry Steve
Published: July 2009

W. Van Winkle defined the utilization distribution (UD) as a probability density that gives an animal's relative frequency of occurrence in a two‐dimensional (x, y) plane. We extend Van Winkle's work by redefining the UD as the relative frequency distribution of an animal's occurrence in all four dimensions of space and time. We then describe a product kernel model estimation method, devising a novel kernel from the wrapped Cauchy distribution to handle circularly distributed temporal covariates, such as day of year. Using Monte Carlo simulations of animal movements in space and time, we assess estimator performance. Although not unbiased, the product kernel method yields models highly correlated (Pearson's r = 0.975) with true probabilities of occurrence and successfully captures temporal variations in density of occurrence. In an empirical example, we estimate the expected UD in three dimensions (x, y, and t) for animals belonging to each of two distinct bighorn sheep (Ovis canadensis) social groups in Glacier National Park, Montana, USA. Results show the method can yield ecologically informative models that successfully depict temporal variations in density of occurrence for a seasonally migratory species. Some implications of this new approach to UD modeling are discussed.
Predator size, prey size, and dietary niche breadth relationships in marine predators
Authors: Costa Gabriel C.
Published: July 2009

Based on geographical and home range sizes, physiology, and gape limitation, a positive relationship between predator size and diet breadth is expected. Alternatively, larger predators might avoid smaller prey; in this case no relationship would be found. Here, I used a large data set on the diets of marine predators to describe and identify mechanisms responsible for the relationships among predator body size, diet breadth, and the mean, minimum, maximum, and variance of prey size. I found no relationship between predator size and diet breadth. Mean, minimum, maximum, and variance of prey size were all positively associated with predator size. I found that larger predators increase their minimum and maximum prey size with similar slopes, which explains the lack of relationship between predator size and diet breadth. The results support predictions of the hypothesis that optimal foraging is the main factor constraining the shape of the relationships among predator size, prey size, and diet breadth. Future research should focus on examining the relationship between body size and the breadth of different niche axis across different groups of organisms to assess whether a positive relationship between body size and niche breadth is a general rule in macroecology.
Compensatory growth in an aquatic plant mediates exploitative competition between seasonally tied herbivores
Authors: Hidding Bert , Nolet Bart A. , Boer Thijsde , Vries Peter Pde , Klaassen Marcel
Published: July 2009

The degree to which vertebrate herbivores exploitatively compete for the same food plant may depend on the level of compensatory plant growth. Such compensation is higher when there is reduced density‐dependent competition in plants after herbivore damage. Whether there is relief from competition may largely be determined by the life‐history stage of plants under herbivory. Such stage‐specific compensation may apply to seasonal herbivory on the clonal aquatic plant sago pondweed (Potamogeton pectinatus L.). It winters in sediments of shallow lakes as tubers that are foraged upon by Bewick's Swans (Cygnus columbianus bewickii Yarrell), whereas aboveground biomass in summer is mostly consumed by ducks, coots, and Mute Swans. Here, tuber predation may be compensated due to diminished negative density dependence in the next growth season. However, we expected lower compensation to summer herbivory by waterfowl and fish as density of aboveground biomass in summer is closely related to photosynthetic carbon fixation. In a factorial exclosure study we simultaneously investigated (1) the effect of summer herbivory on aboveground biomass and autumn tuber biomass and (2) the effect of tuber predation in autumn on aboveground biomass and tuber biomass a year later. Summer herbivory strongly influenced belowground tuber biomass in autumn, limiting food availability to Bewick's Swans. In contrast, tuber predation in autumn by Bewick's Swans had a limited and variable effect on P. pectinatus biomass in the following growth season. Whereas relief from negative density dependence largely eliminates effects of belowground herbivory by swans, aboveground herbivory in summer limits both above‐ and belowground plant biomass. Hence, there was an asymmetry in exploitative competition, with herbivores in summer reducing food availability for belowground herbivores in autumn, but not the other way around.
Multi‐state succession in wetlands: a novel use of state and transition models
Authors: Zweig C. L. , Kitchens W. M.
Published: July 2009

The complexity of ecosystems and mechanisms of succession are often simplified by linear and mathematical models used to understand and predict system behavior. Such models often do not incorporate multivariate, nonlinear feedbacks in pattern and process that include multiple scales of organization inherent within real‐world systems. Wetlands are ecosystems with unique, nonlinear patterns of succession due to the regular, but often inconstant, presence of water on the landscape. We develop a general, nonspatial state and transition (S and T) succession conceptual model for wetlands and apply the general framework by creating annotated succession/management models and hypotheses for use in impact analysis on a portion of an imperiled wetland. The S and T models for our study area, Water Conservation Area 3A South (WCA3), Florida, USA, included hydrologic and peat depth values from multivariate analyses and classification and regression trees. We used the freeware Vegetation Dynamics Development Tool as an exploratory application to evaluate our S and T models with different management actions (equal chance [a control condition], deeper conditions, dry conditions, and increased hydrologic range) for three communities: slough, sawgrass (Cladium jamaicense), and wet prairie. Deeper conditions and increased hydrologic range behaved similarly, with the transition of community states to deeper states, particularly for sawgrass and slough. Hydrology is the primary mechanism for multi‐state transitions within our study period, and we show both an immediate and lagged effect on vegetation, depending on community state. We consider these S and T succession models as a fraction of the framework for the Everglades. They are hypotheses for use in adaptive management, represent the community response to hydrology, and illustrate which aspects of hydrologic variability are important to community structure. We intend for these models to act as a foundation for further restoration management and experimentation which will refine transition and threshold concepts.
Is the patch size distribution of vegetation a suitable indicator of desertification processes?
Authors: Maestre Fernando T. , Escudero Adrián
Published: July 2009

The monitoring of desertification processes, and particularly the development of “early‐warning” systems, is an increasingly important development in the management of drylands. It has been shown that the patch size distribution of dryland vegetation can be described using power laws and that deviations from such patterns may be used as an early‐warning signal for the onset of desertification. We tested this idea using data from 29 semiarid steppes located along a latitudinal gradient in Spain. A truncated power law (TPL) fitted the patch size distribution of perennial vegetation better than a power law in all the evaluated sites. Variations in this distribution, as measured with the scaling exponent (γ) of the TPL, were not related to total perennial cover, but a negative logarithmic relationship was found between γ and soil variables related to desertification processes (total nitrogen, total phosphorus, and organic carbon). A positive and stronger linear relationship was found between total perennial cover and the same soil variables. Our results suggest that deviations from a patch size distribution characterized by a power law are not directly related to desertification. They also indicate that plant cover can be used to effectively monitor key variables linked to desertification processes.
The Influence of Macro Structure on the Foreign Market Performance of Transnational Firms: The Value of IGO Connections, Export Dependence, and Immigration Links
Authors: Rangan Subramanian , Sengul Metin
Published: July 2009

This study assesses macro, state-centered structural influences on the foreign host market performance of transnational firms, highlighting sanctioning and monitoring. We hypothesize that transnational firms from home countries that have more structural links to a focal host country through (1) common membership in inter-governmental organizations, (2) the host's export dependence, and (3) immigration will be better able to allay concerns about value appropriation vis-à-vis both public and private actors in that host country. Those transnational firms will have more incentive to create value in that host country and should experience greater success in economic exchange there. Regression results, based on the 2000–2001 relative sales performance of foreign transnationals from a variety of home countries operating in six large host countries across more than 35 industries, confirm that our three indicators of structure have positive, direct, and independent effects on transnationals' foreign market performance. Dependence and immigration enable sanctioning and monitoring and, beyond capabilities and trust, are additional mechanisms in explaining transnationals' foreign market performance.
Superadiabatic Lean Catalytic Combustion in a High-Pressure Reactor
Authors: Budzianowski Wojciech M. , Miller Ryszard
Published: July 2009

The isobaric lean catalytic combustion in a high-pressure recuperative reactor in view of gas turbine technologies is examined. A new type of the T/P bifurcation diagram is revealed and elucidated. It is found that the reactor thermally stabilizes at higher pressures. The elevated P to 0.5 MPa extends bifurcation isola for mfin, i.e. each fold is improved by approximately 15%. The thermal and concentration hysteresis bifurcation diagrams are also improved, i.e. the ignition temperature was decreased from 490 to 475 K and the extinction concentration from 177 to 157 ppmv, respectively. The pressure drops are alleviated by the factor of P/P0 slightly corrected for the gas thermal expansion effect. It is also revealed, that the intra-phase mass transfer resistances are reduced at elevated pressures. The fuel conversion pressure dependences are provided for some types of high-pressure reactors.
Development of Image Based Modeling for Determination of Oil Content and Days Estimation for Harvesting of Fresh Fruit Bunches
Authors: Razali Mohd. Hudzari , Wan Ismail Wan Ishak , Ramli Abdul Rahman , Sulaiman Md. Nasir , Harun Mohd. Haniff
Published: July 2009

In this study, the relationship of oil extraction rate (OER) and fruit ripeness will be determined. The sample of oil palm fruits was collected from the unripe until the overripe stage and the oil content of the mesocarp for fresh fruit bunches (FFB) was extracted by using bunch analysis procedure to get the oil extraction rate. Using the same samples of FFB, the pixel value of images which measure in hue, was determined by developed image analysis software. The images were captured under an outdoor environment in an oil palm plantation. The sunlight intensity of environment was recorded using Extech light meter at various times of the day from morning to afternoon in the oil palm plantation. The result of the experiment that showed a good relationship was found between the oil content of FFB with its image pixel values. The mathematical model was developed in determining the optimum days for FFB harvesting.
A New Mixing-Cell-in-Series Model to Predict Breakthrough Curve in Chemically Heterogeneous Media at Column Scale
Authors: Semra Safia , Sardin Michel , Simonnot Marie-Odile
Published: July 2009

The paper aims at modelling linearly adsorbed solute breakthrough curves into chemically heterogeneous media at column scale. The model was developed according to the mixing-cell-in-series approach and provided a general expression of the reduced variance for either water tracer or linearly adsorbed solute into either chemically homogeneous or heterogeneous medium. According to the experimental investigation of Semra et al. (2008), medium activity was assumed discrete with a known mean capacity. The chemical heterogeneity scale was assessed by the inverse of the ratio of active grains number to the total grains one. Discussion of the heterogeneous model results was accomplished considering breakthrough curve moments. Moment analysis showed that respective effects of interaction and transport are no longer independent from each other even when adsorption is linear. For a constant mean capacity and a constant hydrodynamic dispersion, the effective dispersion, accounted for by the temporal reduced variance, increases linearly with the chemical heterogeneity scale and the breakthrough spreading increase is favoured by high capacities. Moreover, mathematical form of the reduced variance predicts asymmetric breakthrough curves even in the case of equilibrium assumption. Considering kinetics, the model shows additive but independent effects of kinetics and hydrodynamics as in the case of chemically homogeneous media; it shows also independent kinetic effects from heterogeneity. Finally, modelling results were coherent with experimental observations made by Semra et al. (2008).
The impact of the global crisis on transition economies
Authors: Nuti Mario
Published: July 2009

All forecasts for transition countries - the 29 EBRD countries of operation - since mid-2008 have been repeatedly downgraded. The latest forecasts (May 2009) envisage an average income decline of 5 per cent in 2009 and only a small recovery of 1.4 per cent in 2010; performance is very diverse. In general, transition countries faced two shocks: a sudden stop and reversal of capital inflows, and an exports collapse due to the global slump. More specific factors include: 1) Home made sub-primes (domestic loans to households, enterprises and governments originally denominated in foreign currency); 2) External imbalances; 3) Worsening terms of trade for primary products exporters; 4) Fall or reversal of FDI and portfolio investment inflows; 5) Funds withdrawal by foreign banks; 6) External demand reduction; 7) Differences in initial positions and policy response. Earlier membership of the Euro by the new member states through a relaxation of Maastricht rules might have been beneficial, but the current crisis is no time for changing or bending rules. By comparison with the transition recession of the 1990s, the current recession is much smaller and shorter, it benefits from more generous assistance from the international community, and from the more enlightened fiscal and monetary policies now uncharacteristically recommended by International Financial Organizations.
The influence of culture on human resource management processes and practices: The propositions for Serbia
Authors: Bogicevic-Milikic Biljana
Published: July 2009

This paper attempts to address the influence of national culture on HRM practices and processes in order to draw conclusions for Serbian HR practitioners, multinational corporations operating in Serbia, and any other country or organizational context that has similar cultural characteristics. To achieve this we first review the relevant literature to identify the interdependencies between Hofstede's cultural dimensions and HRM practices and processes. On the basis of recognized relationships we put forward 11 propositions about likely appropriate HRM practices (such as job analysis, recruitment and selection, human resource planning and career management) for the Serbian cultural context, characterized by high Uncertainty Avoidance, high Power Distance, Collectivism and Femininity.
Chlamydia trachomatis in women
Authors: Jerant-Patic Vera , Milosevic Vesna , Kozarev Gordana
Published: July 2009

The authors present results of a planned prospective study of infections with Chlamydia trachomatis in women. Direct immunofluorescence test (DIF) for proving Chlamydia trachomatis antigens in endocervical smear (by means of monoclonal antibodies), ELISA test for proving IgG antibodies against Chlamydia trachomatis in sera and RVK method for proving antibodies against group Chlamydia-antigen were applied to test 288 women (aged 19-67), previously thoroughly anamnestically and clinically examined. Chlamydia trachomatis infection was found in 29.51% of the cases, equally distributed in all age groups. The authors analyzed frequency of Chlamydia positive findings according to clinical diagnoses, parity, relevant data from gynecological history, as well as results of vaginal secretion tests and Papanicolaou smear findings.
Application of enoxaparin simultaneously with fibrinolysis in patients with acute myocardial infarction with ST-elevation
Authors: Despotovic Nebojsa , Loncar Goran , Nikolic-Despotovic Maja , Ilic Marjan , Dimkovic Sinisa , Miric Milutin
Published: July 2009

Introduction Applied simultaneously with fibrinolytic therapy, low-molecular heparin enoxaparin is showing the potential of improving efficacy with rare adverse effects. Our objective was to investigate if enoxaparin with streptokinase (SK) in patients with acute myocardial infarction (AMI) had better effect than unfractioned heparin (UFH). Material and methods The patients with AMI with ST elevation where SK was applied, were divided into two groups: 1. in the study group (N=32, SK+E) both SK and enoxaparin were administered (E, 30 mg intravenously before SK, then after SK 80 mg subcutaneously every 12 hours for 3 days); 2. the patients of the control group were given continuous infusion of UFH 4 hours after SK (1000 i.j. per hour, 3 days). Two groups were similar regarding average age, previous coronary events and diabetes mellitus. Results The reperfusion, depending mostly on fibrinolytic therapy, was successful in both groups (71.9% vs. 65.8%). The recurrent ischemia was less frequent in the group where enoxaparin was used (18.8% vs. 40.6%, p=0.055), as well as heart failure (15.6% vs. 53.2%, p=0,095). There was no difference in adverse effects. Conclusions Enoxaparin used simultaneously with streptokinase in patients with AMI with ST elevation was safe and effective. The recurrent ischemia, the parameter of 'infarcted' coronary artery reoclusion, is less frequent in patients who had enoxaparin than unfractioned heparin with fibrinolytic therapy.
Body composition and bone mineral density of prepubertal boys involved in different kinesiologic treatments
Authors: Obradovic Borislav , Madic Dejan , Milosevic Zoran , Maksimovic Nebojsa , Mikalacki Milena , Kovacev-Zavisic Branka
Published: July 2009

Introduction. It is well known that physical activity has an anabolic effect on the bone tissue. But there is a lack of information about the effect of intensive physical activity in childhood, particularly at the prepubertal stage. The type, frequency, intensity, and duration of activity that best produce the desired increases in mass and strength of human bones have not yet been well determined. Material and methods. To examine the influence of different kinesiological treatments on body composition and bone mineral density we studied a group of prepubertal boys at the starting phase of their peak bone mass acquisition. 90 healthy prepubertal boys took part in this study. The sport group consisted of 28 swimmers (aged 10.80.8) and 32 soccer players (aged 10.70.5), who had been training their chosen high-level sport activity for at least 1 year (8-12h per week for swimmers, 10-15h per week for soccer players). 30 boys (aged 11.2?0.7) doing 1.5h per week of physical activity in school served as a control group. Bone mineral density measurements of the left and right calcaneus were done by ultrasound densitometer 'Sahara'. The body composition was assessed by Body Fat Analyser 'BES 200 Z'. Results. There were significant differences between soccer players and control group as regards fat mass and bone mineral density (p<.01). Besides, significant differences were determined between a group of swimmers and control group as regads fat mass (p<.03), while the differences in bone mineral density were not very obvious (p<.67).
Primary fallopian tube carcinoma
Authors: Mladenovic-Segedi Ljiljana
Published: July 2009

Introduction. Primary fallopian tube carcinoma is extremely rare, making 0.3-1.6% of all female genital tract malignancies. Although the etymology of this tumor is unknown, it is suggested to be associated with chronic tubal inflammation, infertility, tuberculous salpingitis and tubal endometriosis. High parity is considered to be protective. Cytogenetic studies show the disease to be associated with over expression of p53, HER2/neu and c-myb. There is also some evidence that BRCA1 and BRCA2 mutations have a role in umorogeneis. Clinical features. The most prevailing symptoms with fallopian tube carcinoma are abdominal pain, abnormal vaginal discharge/bleeding and the most common finding is an adnexal mass. In many patients, fallopian tube carcinoma is asymptomatic. Diagnosis. Due to its rarity, preoperative diagnosis of primary fallopian tube carcinoma is rarely made. It is usually misdiagnosed as ovarian carcinoma, tuboovarian abscess or ectopic pregnancy. Sonographic features of the tumor are non-specific and include the presence of a fluid-filled adnexal structure with a significant solid component, a sausage-shaped mass, a cystic mass with papillary projections within, a cystic mass with cog wheel appearance and an ovoid-shaped structure containing an incomplete separation and a highly vascular solid nodule. More than 80% of patients have elevated pretreatment serum CA-125 levels, which is useful in follow-up after the definite treatment. Treatment. The treatment approach is similar to that of ovarian carcinoma, and includes total abdominal hysterectomy and bilateral salpingo-oophorectomy. Staging is followed with chemotherapy.
Sudden cardiac death in athletes
Authors: Mijailovic Zdravko , Stajic Zoran , Tavciovski Dragan , Matunovic Radomir
Published: July 2009

The entity of sudden cardiac death in young athletes has been known since the year 490 B.C. when young Greek soldier Phidipides had run the distance from Marathon to Athens and suddenly fell down dead. In the last twenty years, sudden death of famous athletes have attracted huge attention of medical and social community; afterwards both American and European Cardiology Societies started to publish periodically guidelines for preparticipation screening. These guidelines have focused on both identifying athletes with potential cardiovascular risk for sudden death and eligibility conditions for athletes participating in competitive sports. Structural and functional abnormalities causing sudden cardiac death in young athletes have been identified by autopsy-based studies. Unrecognized congenital cardiovascular abnormalities associated with excessive physical effort create background for electrophysiological instability and occurrence of malignant ventricular tachyarrhythmia and consequent death. The most frequent causes of sudden cardiac death in young athletes include hypertrophic cardiomyopathy, anomalies of the coronary arteries and idiopathic left ventricular hypertrophy. Current ACC/AHA & ESC guidelines should be widely used in order to reduce potential sudden cardiac death in young athletes.
Application of ribavirin in patients having hemorrhagic fever with renal syndrome
Authors: Zivkovic Milovan , Todorovic Zoran , Canovic Predrag , Mijanovic Zeljko
Published: July 2009

Introduction. Hemorrhagic fever with renal syndrome (HFRS) is an acute infective disease of a zoonose type characterized by an abrupt beginning, prominent hemorrhagic syndrome as well as symptoms and signs of acute renal insufficiency. The clinical picture of this disease, which is leading in terms of its natural principal seat in the region of Northern-east Montenegro, ranges from non-apparent to very severe forms and mortality it causes is about 10%.Up to date, no efficient etio-trophic means has been discovered. Several studies suggest that an early use of anti virus medicament Ribavirine leads to decrease of mortality rate. The main aim of this study is to present our results achieved in an attempt to apply this medicament in treating HFRS. Material and methods. In total, we have treated 58 patients with symptoms and signs of HGSBS. Five of them, who were admitted to the Department in the first three days were treated by Ribavirine orally in doses of 2x400 mg. Compared to patients who were not treated by Ribavirine, a faster decrease of thrombocytes was noticed in them, which required the discontinuation of the medicament treatment. Thereafter, thrombocytes started to increase and their normalization followed faster than in patients who were not treated by this medicament. The above patients developed a moderately severe clinical picture of the disease, and middle maximum values of urea and creatinine were lower in patients who were not treated by the medicament. No patient developed a severe form of the disease and there were neither dialyzed nor died ones. The mortality rate in patients who were not treated by the medicament was 3.44% and the percent of the dialyzed was 5.17%. Results. Application of Ribavirine at the very beginning of HFRS is considered to be with a very good reason in combination with obligatory follow up of clinical and laboratory parameters and particularly of thrombocyte values, the decrease of which can lead to spontaneous bleedings. Because of the small number of patients to whom we gave this medicament it is difficult to come to a conclusion on the extent of its affect on the clinical picture in our patients.
Identification and analysis of stress factors at nursing workplace: A comparative study of four clinical departments
Authors: Milutinovic Dragana , Grujic Nikola , Jocic Neda
Published: July 2009

Introduction. Several studies show that nursing is, by its very nature, an occupation exposed to a high degree of stress. The main aims of the present research were to analyze the presence and to identify occupational stress factors and assess stress levels among nurses in clinical/hospital settings. Material and Methods. The research was conducted as a cross-sectional study. The sample included nurses (n=205) employed in different settings, who were also control groups to each other. Expanded Nursing Stress Scale and an additional questionnaire created for the purpose of this investigation were used as research instruments. Results. The results show that stressful situations, in the psychological occupational environment are the greatest stress factors regardless of the workplace; in regard to sociodemographic determinants, married nurses have significantly higher average values as compared to unmarried ones (p<0.05), and the values statistically significantly lower in nurses under 30 years of age, with less than 10 years of work experience (p<0.01). Workload is a potential stress factor from the physical environment, whereas average values of this stress factor highly statistically differ in regard to the workplace (p<0.01). Nurses working in settings without support from their superiors and engaged in inter-professional conflicts, especially between nurses and physicians, face a great problem. Conclusion. It is important to promote conditions of work (work space, providing new equipment), organization of work, as well as social relationships, which is in accordance with the recommendations of ICN.
Single dose of antibiotic prophylaxis in elective cesarean sections
Authors: Grujic Zorica , Sabo Ana , Grujic Ilija , Kopitovic Vesna , Papovic Maja
Published: July 2009

Introduction. The aim of our study was to determine whether a single-dose preoperative administration of antibiotics was sufficient to prevent intra and postoperative infections in the parturients without a high risk of developing an infection, in whom the delivery was completed by cesarean section, as well as to answer whether the administered dose of antibiotics satisfied the requirements of therapeutic concentrations necessary to protect against infection in the period during the surgical procedure and during the first 6 postoperative hours. Material and methods. All investigated pregnant women were planned to have elective cesarean section as a mode of delivery. They were distributed in groups depending on the type (cephalexin, gentamycin and cephazolin) of antibiotic prophylaxis administered as a single dose. In all patients the clinical postoperative course was followed for possible infection. The concentrations of antibiotics were estimated immediately and 6h following the operation. The estimation of antibiotic concentrations was done by the method of liquid chromatography (for antibiotics belonging to the group of cephalosporins), i.e. RIA method for antibiotics from the group of aminoglycosides. Results and conclusion. The total number of infections in investigated groups was 5.18%. The measured mean concentrations of administered antibiotics following the operation and 6 h later were above MIC. This is a proof that the obtained antibiotic prophylaxis by a single dose administration of anbtibiotic is sufficient to prevent the invasion of pathogenic microorganisms from the skin.
The acute and subchronic effect of 3,4-methylenedioxymethamphetamine on body temperature in rats
Authors: Simic Ivan , Malicevic Zivorad
Published: July 2009

Introduction. The consumption of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) is known to cause severe hyperthermia in humans. This is of extreme importance since ecstasy is often consumed at 'rave' parties, where dancing takes place in a warm environment, which may exacerbate the effect of MDMA on thermoregulation. The present study was performed in order to evaluate the effects of single and repeated administration of MDMA on body temperature in Wistar rats. Material and methods. The study included 72 male Wistar rats, housed in groups of four in cages at a room temperature of 222oC. They were divided in two groups. The rats in the first group were treated with oral solution of MDMA (5 mg/kg, 10 mg/kg, 20 mg/kg, 40 mg/kg) and their temperature was measured hourly until 8th hour. The rats in the second group were treated with oral solution of MDMA (5 mg/kg, 10 mg/kg, 20 mg/kg) every day during 15 days and their temperature was measured daily at 0th, 1st, 3rd, 5th and 8th hour. Temperature was measured by inserting a thermocouple probe 2,5 cm into the rectum. Results. Both groups showed dose dependent increase of body temperature, determined by rectal temperature measurements. The magnitude of hyperthemic response caused by subchronic administration of MDMA was markedly diminished during the experiment. Conclusion. The hyperthermic effect of MDMA was dose-dependent. The magnitude of the hyperthermic response was markedly diminished in subchronic administration.
Acute renal pain as an adverse reaction of the rabies immunization
Authors: Lalosevic Dusan
Published: July 2009

Introduction. HRIG is the best preparate in rabies prophylaxis, and it's considered that optimal dose is 20 international units per kilogram and must not been reduced or overdosed. HRIG have to be injected infiltrative around bite wounds, and if after that remains a part of the dose, it has to be given in gluteal muscle. Application only in gluteus is vitium artis. Case report. At one patient immunized against rabies has occured acute bilateral renal pain and fever at time of immunization against rabies, and because of that vaccination must been stopped after the 3rd dose of vaccine. Patient was a 26-year-old female without significant pre-existing disease, bitten by stray dog. After the start of immunization, because the wrong direction, she received about 2.5 more amount of human rabies immunoglobuline (HRIG) then is recommended on declaration at etiquette of ampoule, and only in gluteus in quantity of 10.5 ml. Discussion. Glomerulonephritis after rabies vaccination until now was described just once by Singhal et al. in 1981. year. Acute renal pain, after rabies vaccine, which aggravated after repeated vaccine doses in our patient who received overdosed HRIG, may be explained by immunopathological mechanism, rather with formation of circulating immune complexes, their precipitation on the glomerular basement membrane and developing glomerulonephritis. Conclusion. Low weight soluble molecular immune complexes formed when antigen is in excess, as in case after repeated doses of rabies vaccine, circulate and precipitate on glomerular membrane and causes glomerulonephritis. As contribution to this explanation, is that symptoms as renal pain disappeared after interrupting vaccination protocol in our patient.
Hospital morbidity and mortality of adolescents in Vojvodina
Authors: Roncevic Nevenka , Popadic-Gacesa Jelena , Grujic Vera , Arsic Miodrag , Pericin Ivana
Published: July 2009

Introduction. The aim of this study was to analyze hospital morbidity and mortality of adolescents in Vojvodina in 2004. Material and methods. The analyzed data for hospital morbidity were obtained from the Reports on diseases and conditions of hospitalized patients in the Service for stationary-hospital treatment. Hospital mortality was analyzed on the basis of Documentation tables of vital statistics of Republic of Serbia. In order to have better insight into the pathology, the adolescents were divided by sex and age (the younger ones from 10-14 years, and the older ones, from 15-19 years). Results . The hospital morbidity of adolescents in Vojvodina in 2004 was 47/1.000 adolescents, while in 1983 it was 53/1.000 adolescents. The most frequent indications for hospitalization of the adolescents were respiratory, digestive diseases, and injuries, poisoning and consequences of an external factor influences. The overall mortality rate was 39.68/100.000 adolescents and in 1988 44.74/100.000 adolescents. Hospital mortality rate in Vojvodina in 2004 was 16.18/100.000 adolescents and in 1986 11.65/100.000 adolescents. The male adolescents most frequently died in hospitals because of tumors, and female ones because of injuries, poisoning and consequences of external factor influences. Discussion and conclusion. Morbidity structure was not changed compared to the previous period. Older and female adolescents were more frequently hospitalized. There was a decrease in adolescent mortality for 15.5% compared to the previous 15 years. Hospital mortality rate was higher than before. Older adolescents had three times the death rate of younger. Mortality rates for male adolescents were three times rates for females. Programs for adolescents' health care must be implemented fully, with engagement of whole community services, in order to prevent and cure diseases adequately and to enhance quality of life.
Poststroke depression: Diagnosis of depression, phenomenology and specificity of depressive symptoms
Authors: Rabi-Zikic Tamara , Nedic Aleksandra , Zarkov Marija , Slankamenac Petar , Dobrenov Dragica , Zivanovic Zeljko
Published: July 2009

The diagnosis of depression. Depressive disorder is nowadays diagnosed by the two widely used diagnostic systems - International Classification of Diseases of the World Health Organization, 10th revision and the Diagnostic and Statistical Manual Criteria of the American Psychiatric Organisation, 4th edition. The criteria for depressive disorder used in these two systems are almost identical. Poststroke depression. The diagnosis of depression may be difficult to establish in stroke patients, especially in patients with aphasia/dysphasia, anosognosia and other cognitive dysfunction. Major vs. minor poststroke depression, specificity and sensitivity of depressive symptoms: The phenomenology of major poststroke depression has been found to be similar to that of primary depression, and it appears that minor and major are not stages of the same continuum, but rather separate entities. Contrary to common opinion, non specific somatic symptoms do not hinder the diagnosis of poststroke depression and can be highly discriminative and crucial in the evaluation of poststroke depression. Validity of the poststroke depression diagnosis Studies have shown that a valid diagnosis of poststroke depression may be established successfully using structured or semi-structured neuropsychiatric interviews, according to the current Diagnostic and Statistical Manual Criteria. Conclusion. It appears that no new diagnostic tools specific for major depression in stroke patients are necessary. The existing diagnostic procedures will fail to diagnose or misdiagnose depression only in few stroke patients.