Assessing the validity and sensitivity of microbial processes within a hydrodynamic model.

Eutrophication due to excess anthropogenic nutrients in waterways is a significant issue worldwide. The pressure-stressor-response of a waterway to excessive nutrient loading is reliant on numerous physical and biological factors, including hydrodynamics and microbial processing. While substantial progress has been made towards simulating these mechanisms there are limited multi-disciplinary studies that relate the physical hydrodynamics of a site with the ecological response from linked laboratory and field studies. This paper presents the development of a coupled hydrodynamic and aquatic ecosystem response model, expanded to include an integrated microbial loop, that allows the explicit representation of heterotrophic bacteria growth and dissolved organic nutrient mineralisation. A unique long-term water quality dataset at an estuary in south-eastern Australia was used to validate and assess the model's sensitivity to complex biophysical processes driving the observed water quality variability. Results indicate that explicit time-varying bacterial mineralisation rates provide a substantially improved understanding of the broader aquatic ecosystem response than assigned fixed bulk rate parameter values, which are typically derived from non-local literature. Implementation of a microbial loop at the study site indicated that the model is sensitive to the boundary conditions, in particular catchment loads, with both net transport rates and the net growth rates of heterotrophic bacteria demonstrating different responses. Under average flow conditions, a smaller net transport and reduced nutrient availability has a pronounced effect of lowering net growth rates through the applied limitation factors. During high flow conditions, freshwater inflows increased net transport and nutrient loads, which resulted in higher net growth rates. Further, temporal variability in water temperature had a compounding effect on the model's response sensitivity. This approach has broader application in other riverine systems subject to eutrophication, and in interrogating linkages in hydrodynamic and microbial mediated processes (e.g., productivity). Future studies are recommended to better understand the sensitivity of aquatic ecosystem response models to microbial net growth rate kinetics at different temperatures and from top-down predation (e.g., zooplankton grazing).

Implications of bacterial mineralisation in aquatic ecosystem response models.

Widespread wastewater pollution is a major barrier to the sustainable management of freshwater and coastal marine ecosystems worldwide. Integrated multi-disciplinary studies are necessary to improve waterway management and protect ecosystem integrity. This study used the Generalised Likelihood Uncertainty Estimation (GLUE) methodology to link microbial community ecotoxicology laboratory data to a mechanistic aquatic ecosystem response model. The generic model provided good predictive skill for major water quality constituents, including heterotrophic bacteria dynamics (r2 = 0.91). The model was validated against observed data across a gradient of effluent concentrations from community whole effluent toxicity (WET) laboratory tests. GLUE analysis revealed that a combined likelihood measure increased confidence in the predictive capability of the model. This study highlights the importance of calibrating aquatic ecosystem response models with net growth rates (i.e., sum of the growth minus loss rate parameter terms) of biological functional groups. The final calibrated net growth rate value of heterotrophic bacteria determined using the GLUE analysis was selected to be 0.58, which was significantly greater than the average literature value of -0.15. This finding demonstrated that use of literature parameter values without a good understanding of the represented processes could create misleading outputs and result in unsatisfactory conclusions. Further, fixed bulk mineralisation rate literature values are typically higher than realistically required in aquatic ecosystem response models. This indicates that explicitly including bacterial mineralisation is crucial to represent microbial ecosystem functioning more accurately. Our study suggests that improved data collection and modelling efforts in real-world management applications are needed to better address nutrients released into the natural environment. Future studies should aim to better understand the sensitivity of aquatic ecosystem response models to bacterial mineralisation rates.

Wastewater effluents cause microbial community shifts and change trophic status.

Widespread wastewater pollution is one of the greatest challenges threatening the sustainable management of rivers globally. Understanding microbial responses to gradients in environmental stressors, such as wastewater pollution, is crucial to identify thresholds of community change and to develop management strategies that protect ecosystem integrity. This study used multiple lines of empirical evidence, including a novel combination of microbial ecotoxicology methods in the laboratory and field to link pressure-stressor-response relationships. Specifically, community-based whole effluent toxicity (WET) testing and environmental genomics were integrated to determine real-world community interactions, shifts and functional change in response to wastewater pollution. Here we show that wastewater effluents above moderate (>10%) concentrations caused consistent significant shifts in bacterial community structure and function. These thresholds of community shifts were also linked to changes in the trophic state of receiving waters in terms of nutrient concentrations. Differences in the community responses along the effluent concentration gradient were primarily driven by two globally relevant bacterial indicator taxa, namely Malikia spp. (Burkholderiales) and hgcI_clade (Frankiales). Species replacement occurred above moderate effluent concentrations with abundances of Malikia spp. increasing, while abundances of hgcI_clade decreased. The responses of Malikia spp. and hgcI_clade matched gene patterns associated with globally important nitrogen cycling pathways, such as denitrification and nitrogen fixation, which linked the core individual taxa to putative function and ecosystem processes, rarely achieved in previous studies. This study has identified potential indicators of change in trophic status and the functional consequences of wastewater pollution. These findings have immediate implications for both the management of environmental stressors and protection of aquatic ecosystems.

A novel real-world ecotoxicological dataset of pelagic microbial community responses to wastewater.

Real-world observational datasets that record and quantify pressure-stressor-response linkages between effluent discharges and natural aquatic systems are rare. With global wastewater volumes increasing at unprecedented rates, it is urgent that the present dataset is available to provide the necessary information about microbial community structure and functioning. Field studies were performed at two time-points in the Austral summer. Single-species and microbial community whole effluent toxicity (WET) testing was performed at a complete range of effluent concentrations and two salinities, with accompanying environmental data to provide new insights into nutrient and organic matter cycling, and to identify ecotoxicological tipping points. The two salinity regimes were chosen to investigate future scenarios based on a predicted salinity increase at the study site, typical of coastal regions with rising sea levels globally. Flow cytometry, amplicon sequencing of 16S and 18S rRNA genes and micro-fluidic quantitative polymerase-chain reactions (MFQPCR) were used to determine chlorophyll-a and total bacterial cell numbers and size, as well as taxonomic and functional diversity of pelagic microbial communities. This strong pilot dataset could be replicated in other regions globally and would be of high value to scientists and engineers to support the next advances in microbial ecotoxicology, environmental biomonitoring and estuarine water quality modelling.

Making global river ecosystem health assessments objective, quantitative and comparable.

Assessing and comparing global river ecosystem health in an objective and quantitative way remains a major challenge. In this study the widely-used semi-quantitative methods Rapid Biological assessment Protocols (RBPs) was used to determine the health of rivers. The findings were then compared to the results derived from our new UAV (Unmanned aerial vehicles) orthophotographic imagery method. This method quantitatively and objectively assesses river ecosystem health. As a comparison, our method was used to quantitatively measure distance and areas of a range of hydrological and biological attributes thus improving the accuracy of distance- and area-related indices, consequently avoiding subjective errors in these estimations that is fraught in methods like the RBPs. To strengthen the objectivity of the assessment the weights of these indices were objectively determined using the entropy weighting method. This new method was then tested using 9551 UAV orthophotographs taken over six field campaigns. It performed satisfactorily, showing that in our study area the health status of mountain rivers was the best with the highest score of 0.94 out of 1.0. Temporally, the health of the river was better in summer (0.65) compared with that in autumn (0.40). Changes in river ecosystem health were driven by variations in biology and water quality. In contrast the outputs of RBPs, especially in relation to distance and area indices, had ~ 20% uncertainty due to visual errors and subjectivity in estimations by observers. The UAV orthophotographic imaging method proposed in this study can improve the ability to compare the health of rivers across different periods and regions throughout the globe.

Predicting future river health in a minimally influenced mountainous area under climate change.

It has been shown that climate change impacts the overall health of a river's ecosystem. Although predicting river health under climate change would be useful for stakeholders to adapt to the change and better conserve river health, little research on this topic exists. This paper presents a methodology predicting river health under different climate change scenarios. First, a multi-source, distributed, time-variant gain hydrological model (MS-DTVGM) was used to predict the runoff from a mountainous river in eastern China using the data from three existing IPCC5 climate change models (RCP2.6, RCP4.5, and RCP8.4). Next, a model was developed to predict the river's water quality under these scenarios. Finally, a multidimensional response model utilizing hydrology, water quality, and biology was used to predict the river's biological status and ascertain the impact of climate change on its overall health. The river is in a mountainous area near Jinan City, one of China's first "pilot" cities recognized as a "healthy water ecological community." Our results predict that the overall health of the Yufu River, which is minimally influenced by human activities, will improve by 2030 due to the increased river flow due to an increase in rainfall frequency and subsequent peak runoff. However, the total nitrogen concentration is predicted to increase, which is a potential eutrophication risk. Therefore, effective control of nitrogen pollutants entering the river will be necessary. The increase in flow velocity (the annual average increase is ~0.5 m/s) is favorable for fish reproduction. Our methods and results will provide scientific guidance for policy makers and river managers and will help people to better understand how global climate change impacts river health.

Case-series study of hepatic echinococcal cysts in Serbia: viability of scolices, seropositivity and epidemiological characteristics.

Cystic echinococcosis (CE) is an endemic helminthic disease caused by infection with Echinococcus granulosus metacestodes. Although CE is endemic in the Balkan region, the exact epidemiology remains unknown. We conducted a case-series study with the aim of evaluating the correlation between seropositivity, socio-epidemiological data, pre-operative treatment with albendazole and viability of protoscolices in human hepatic hydatid cysts. Consecutive patients with hepatic CE underwent surgery to extract E. granulosis cysts. The viability of protoscolices was measured by their ability to absorb 0.1% eosin. Socio-epidemiological data were collected and serological testing was performed. In the present study, 38 patients (28 adults and 10 children) with hepatic CE were treated surgically. The scolex viability test was positive in 30/38 (79%) samples. All patients with non-viable cysts had seronegative results. The viability test was positive in 11/12 (91.6%) adult patients with pre-operative albendazole treatment and in 9/10 (90%) children. Statistically more patients were from an urban area compared with a rural area (65.8% vs. 15.7%). The increasing number of stray dogs shedding E. granulosus eggs in urban public areas in the Balkans might be the reason for the significant difference in the rate of infection between urban and rural areas in the present study. In addition, uncontrolled slaughtering of livestock, common in rural settlements, and feeding the infected viscera to dogs, favour the maintenance of the parasite cycle. We believe that the results of our study will encourage physicians, veterinarians and health authorities to initiate a programme to prevent and control CE in the Balkan region.

Pure primary osteosarcoma of the breast: a case report.

INTRODUCTION: Mammary sarcomas are relatively uncommon and they represent less than one percent of all primary breast malignancies. Osteosarcoma of the breast, unassociated with other tumors, is distinctly rare, with published references generally limited to case reports and occasional cases in several series encompassing a heterogeneous group of mammary sarcomas and extraosseous osteosarcomas at various sites. The authors present a patient with pure osteosarcoma of the breast, osteoblastic type, with biologically aggressive pattern. CASE REPORT: A 79-year-old lady became aware of a rapidly enlarging lump in the lateral part of the right breast. Clinical examination revealed a firm to hard, mobile, irregular, and painful breast lump measuring about six by four cm. On examination there was no axillary or supraclavicular lymphadenopathy. After initial diagnosis, excisional biopsy without dissection of the axillary lymph nodes was performed. Therefore, the histological and immunohistochemical findings established the diagnosis of pure primary osteosarcoma of the breast. CONCLUSION: Pure osteosarcoma of the breast is extremely rare and needs to be distinguished from a variety of benign and malignant breast lesions producing metaplastic bone. Less than a hundred cases of pure osteosarcoma of the breast were reported, but diagnostic confirmation with immunohistochemistry has been performed in relatively few of these cases.

Is an occupation with vocal load a risk factor for laryngopharyngeal reflux: a prospective, multicentre, multivariate comparative study.

OBJECTIVES: To compare the prevalence of laryngopharyngeal reflux in choristers, teachers and control subjects without vocal load at work and to determine the risk factors for laryngopharyngeal reflux. DESIGN: A prospective, multicentre, multivariate comparative study. PARTICIPANTS: One hundred and nineteen singers from four professional choirs, seventy teachers from four schools and 111 control subjects with an occupation without vocal load. MAIN OUTCOME MEASURES: All participants completed a questionnaire about their dietary habits, height and weight, presence of stress, smoking and allergies, including the nine-item Reflux Symptom Index. The groups of choristers, teachers and the controls were compared with each other with regard to their sex, age, dietary habits, body-mass index, Reflux Symptom Index score and other factors affecting voice quality. The subjects from all three groups with suspected laryngopharyngeal reflux were compared with the subjects without it. The relationship between the Reflux Symptom Index score and the possible risk factors for reflux was estimated. RESULTS: The results showed significantly higher Reflux Symptom Index scores in the choristers than in the teachers and the controls (mean scores, 7.86 versus 6.33, P = 0.044; 7.86 versus 4.80, P = 0.000, respectively), but the number of subjects with suspected laryngopharyngeal reflux (Reflux Symptom Index score >13) did not differ significantly between the groups. The choristers were significantly more often treated for laryngopharyngeal reflux than the teachers and the controls (41%, 17% and 28%, respectively). The occupation chorister and frequently experiencing stress were the only factors that influenced the total Reflux Symptom Index score. CONCLUSIONS: Laryngopharyngeal reflux affects the choristers more often than the teachers or the control subjects without vocal load at work. These results suggest that singing as the main professional activity can notably contribute to the development of the reflux. Vocal load without singing is probably not an important aetiological factor for laryngopharyngeal reflux. The extraoesophageal symptoms affecting voice require treatment for laryngopharyngeal reflux and proper dietary habits especially in the group with high voice quality demands.

Disorder verbal memory in alcoholics after delirium tremens.

AIMS: Alcohol delirium tremens suggests dysfunction of numerous brain regions. Several Authors suggest that alcohol and withdrawal from alcohol could cause neurotoxic lesions in the frontal lobe and thereby affect cognitive function. However, it is not that well known whether the consequences of the damage following delirium are only quantitative or qualitative. PATIENTS AND METHODS: Thirty alcohol-dependent patients after alcohol delirium (ADT-n1 = 30), and 30 alcohol-dependent patients without alcohol delirium (ALC-n2=30) were compared with neuropsychological test-battery. [(Wechsler Bellevue Intelligence Scale - WB form I, Wechsler memory scale and Rey Auditory Verbal Learning Test (RAVLT)]. Examinees were selected as equivalent pairs, in such a manner that they were of approximately same age, i.e. age difference was 0-5 years, they were of the same education level, and difference in the duration of drinking was not more than 3 years. RESULTS: In the group of ADT patients, IQ was 97.53, while it is 109.53 for ALC patients. Mental deterioration of the examined group is 40, and in the control group 13. Group of ADT patients had significantly lower achievements on subtests: arithmetic, block design and digit symbol. ADT patients' average memory quotient (MQ) is 81.8, which is three standard deviations lower compared to ALC patients (MQ 102.2) and standard values, according to Wechsler. In the first repetition of the series of 15 words RAVLT, is no difference (t-test=1.88; p > 0.05), while the difference in other repetitions is significant. Difference is also statistically significant regarding recollection after 30 minutes (t-test=3.66; p < 0.05). CONCLUSION: There is qualitative difference in cognitive deficiencies in alcoholics with delirium tremens and those with no alcohol delirium, while the predominant pathology of the cognitive-amnestic deficiency is in compliance with the dysfunction of the prefrontal lobe. Following alcohol delirium, verbal memory disorders occur within the intellectual decrease and attention disorder in general.

Cisplatin monotherapy with concurrent radiotherapy versus combination of cisplatin and 5-fluorouracil chemotherapy with concurrent radiotherapy in patients with locoregionally advanced cervical carcinoma.

PURPOSE: To compare the efficacy, toxicity and survival of cisplatin monotherapy with concurrent radiotherapy ver-sus combination of cisplatin and 5-fluorouracil (5-FU) with concurrent external beam radiotherapy (EBRT) in patients with locoregionally advanced cervical carcinoma FIGO stages IIB-IV. METHODS: 134 patients with locoregionally advanced, histologically confirmed carcinoma of the uterine cervix were analysed. The first group of patients (n=70; 52.24%) started concomitant chemotherapy on the second day of radiotherapy with single-agent cisplatin 40 mg/m(2) given 2 h before radiotherapy, once a week for 6 courses. The second group of patients (n=64; 47.76%) started concomitant chemotherapy on the second day of radiotherapy with cisplatin 75 mg/m(2). Treatment was continued with 96-h infusion of 5-FU 4 g/m(2) (1 g/ m(2) per day for 5 consecutive days). The patients were irradiated by EBRT followed by intracavitary brachytherapy (ICB). RESULTS: 24- and 42-month survival in the first group were 71.9 and 57.81% and 52.5 and 35.4% in the second group, respectively (p=0.012). Mean time to progression in the first group was 24 months and in second group it was 15.9 months (p=0.012). After 2 years progression was noted in 38.3% of the first and in 62.9% of second group patients (p=0.003). After 40 months 60 patients were without relapse, 35 (57.81%) patients in the first group and 25 (37.147percnt;) patients in the second group (p=0.018). CONCLUSION: Treatment with combined cisplatin and 5-FU with concurrent EBRT was more efficient in comparison to cisplatin monotherapy with concurrent radiotherapy in patients with locoregionally advanced cervical carcinoma, in terms of 12- and 24-month overall survival and disease relapse after 2 years.

The cost of fall related presentations to the ED: a prospective, in-person, patient-tracking analysis of health resource utilization.

UNLABELLED: We prospectively collected data on elderly fallers to estimate the total cost of a fall requiring an Emergency Department presentation. Using data collected on 102 falls, we found the average cost per fall causing an Emergency Department presentation of $11,408. When hospitalization was required, the average cost per fall was $29,363. INTRODUCTION: For elderly persons, falls are a major source of mortality, morbidity, and disability. Previous Canadian cost estimates of seniors' falls were based upon administrative data that has been shown to underestimate the incidence of falls. Our objective was to use a labor-intensive, direct observation patient-tracking method to accurately estimate the total cost of falls among seniors who presented to a major urban Emergency Department (ED) in Canada. METHODS: We prospectively collected data from seniors (>70 years) presenting to the Vancouver General Hospital ED after a fall. We excluded individuals who where cognitively impaired or unable to read/write English. Data were collected on the care provided including physician assessments/consultations, radiology and laboratory tests, ED/hospital time, rehabilitation facility time, and in-hospital procedures. Unit costs of health resources were taken from a fully allocated hospital cost model. RESULTS: Data were collected on 101 fall-related ED presentations. The most common diagnoses were fractures (n = 33) and lacerations (n = 11). The mean cost of a fall causing ED presentation was $11,408 (SD: $19,655). Thirty-eight fallers had injuries requiring hospital admission with an average total cost of $29,363 (SD: $22,661). Hip fractures cost $39,507 (SD: $17,932). Among the 62 individuals not admitted to the hospital, the average cost of their ED visit was $674 (SD: $429). CONCLUSIONS: Among the growing population of Canadian seniors, falls have substantial costs. With the cost of a fall-related hospitalization approaching $30,000, there is an increased need for fall prevention programs.

The impact of heroin on visual memory.

INTRODUCTION AND AIM: Heroin abuse can lead to organic damage of cerebral structures, including sequels in cognitive and affective sphere, which are in positive relation with the duration of substance usage. Memory is one of the cognitive functions which is highly sensitive to opiate toxic effects. The aim of this research was determination of heroin impact on the visual memory of addicts, as well as the existence of specific relation of potential deficiencies in visual memory with the duration of substance use. METHODS: The research included 90 examinees, divided into three groups, depending on the duration of heroin intake. We used questionnaire for basic socio-demographic and addictological traits of examinees; Wechsler's scale for the assessment of the intelligence and Visual Memory Test (TVP), for the assessment of the visual memory. RESULTS: The achievements of heroin addicts with different duration of the substance abuse differ significantly (F = 1.83; df = 12; p < 0.05). Total number of errors examinees make in the first series of TVP (immediate visual memory) grows, almost linearly in the function of the duration of heroin abuse (p < 0.05), but in neither of groups meets criteria for the visual memory impairment. Deficiency of the delayed visual memory occurs in examinees who use heroin for one (total number of errors = 6.46; participation of typical organic errors = 31.7%) and longer than five years (total number of errors = 7.66; participation of typical organic errors = 26.7%). Univariate covariance analysis separates the average daily dosage of heroin as the most significant variable that contributes to the expression of the aforementioned deficiencies (F = 4.21; df = 2; p < 0.05). CONCLUSION: Heroin abuse leads to damage of delayed visual memory, whereby for the observed effect intake of the substance for a period longer than one year is necessary.

The issue of applying marketing on the pharmaceutical market in Serbia.

The issue of applying marketing on the pharmaceutical market has the features of subject-based approach, with the intention to appreciate the specific nature of the products, as well as the special characteristics of the complexly formed demand. The relevance of the issue is related to the above-average performance of the pharmaceutical industry, its role in the generation of humanity's demographic transition, and specific development routes of marketing as a scientific and practical discipline. The sensitive nature of a pharmaceutical product on the one hand generates the intense legislation on this market, whereas on the other, the circumstances of its use generate a specific environment in which the production/consumption of the products of pharmaceutical industry is intensively reflected as a specific medical, cultural, economic and even political phenomenon.

Co-overexpression of bcl-2 and c-myc in uterine cervix carcinomas and premalignant lesions.

To establish the role of co-overexpression of bcl-2 and c-myc protooncogenes in uterine cervix carcinogenesis, we examined 138 tissue samples of low grade cervical squamous intraepithelial lesions (SIL), high grade SIL, portio vaginalis uteri (PVU) carcinoma in situ and PVU carcinoma invasive, stage IA-IIA (study group) and 36 samples without SIL or malignancy (control group). The expression of bcl-2 and c-myc was detected immunohistochemically using a monoclonal antibody. Fisher’s exact test (P<0.05) was used to assess statistical significance. Overexpression of bcl-2 was found to increase in direct relation to the grade of the cervical lesions. High sensitivity was of great diagnostic significance for the detection of these types of changes in the uterine cervix. On the basis of high predictive values it can be said that in patients with bcl-2 overexpression there is a great possibility that they have premalignant or malignant changes in the uterine cervix. Co-overexpression of bcl-2 and c-myc oncogenes was found only in patients with PVU invasive carcinoma (6/26-23.0%). Statistically significant difference was not found in the frequency of co-overexpression in patients with PVU invasive carcinoma in relation to the control group (Fisher’s test; P=0.064). The method's sensitivity of determining these oncogenes with the aim of detecting PVU invasive carcinoma was 23%, while specificity was 72.2%. On the basis of high predictive values (100%), speaking in statistical terms, it can be concluded that all patients with co-overexpression of bcl-2 and c-myc oncogenes will have PVU invasive carcinoma. We confirmed in our research that co-overexpression of bcl-2 and c-myc oncogenes was increased only in PVU invasive carcinoma. However, a more extensive series of samples and additional tests are required to establish the prognostic significance of bcl-2 and c-myc co-overexpression in cervical carcinogenesis.

Abdominal rectus muscle endometriosis after Cesarean section. Extrapelvic localization of endometriosis.

INTRODUCTION: Endometriosis is defined by the presence of functional endometrial tissue outside the uterus, where it is normally located. Endometriosis could has intra and extra pelvic localization. Abdominal endometriosis is the most common localization of extrapelvic endometriosis and is usually developed in the connective tissue surrounding the operation. Very rarely this could be found in the muscle tissue. The mechanical transplantation theory is responsible for the development of scar endometriosis. CASE REPORT: The patient, 35 years old, three years after caesarian section had an operation because of the assumption for the presence of front abdominal hernia, located at the place of previous section. The egg-sized tumor was removed from the abdominal rectus muscle and sent for PH and immunohistochemical analyses. The results showed endometriosis of the muscle with positive estrogen and progesterone receptors. One year after the operation, due to the repeated pains in the scar area, the treatment continued by GNRH analogues and control was performed by serial ultrasound and biochemical markers CA 125. CONCLUSION: Clinical diagnoses of scar endometriosis could be provided by an accurate anamnesis and physical, ultrasound and biochemical examinations. Scar endometriosis should always be considered when the symptoms are present in cyclic manner, hormone depending, mostly after gynecological operations and worsening during menstruation. The problem was diagnosed by pathohistological analyses (Fig. 4, Ref. 20).

Generalized granuloma annulare presenting as arcuate dermal erythema.

Generalized granuloma annulare (GGA) is an uncommon cutaneous disease of unknown origin, characterized by numerous flesh-colored to erythematous papules with or without annular configuration. Clinical associations of GGA with diabetes mellitus, thyroid diseases, malignancies, AIDS, and chronic hepatitis C virus infection have been reported. Therapy has been attempted with various modalities with moderate efficacy. We report a case of GGA presenting as arcuate dermal erythema with excellent therapeutic response to corticosteroid therapy (a short course of intramuscular corticosteroids, a prolonged low oral dose, and topical corticosteroids).

Human Dirofilaria repens infection in Serbia.

Human infection by Dirofilaria repens in Serbia has been increasing steadily. The first case was reported in 1971, presented in the form of a single subcutaneous nodule on the back of a young boy. As established by a literature search, eight additional cases were reported until mid-2001. The most frequent site of infection was subcutaneous tissue, with the exception of two cases, in which parasites were found in subconjunctiva and epididymis. Our study, conducted from 2001 to 2008, encompasses 19 new cases. Most of them (63.1%) presented as ocular or periocular infections, in which the parasite was typically found under the conjunctiva. In other cases a parasitic nodule was localized in the temporal region of the head, epididymis, testicle, abdomen, breast or arm. The diagnosis was made by morphological and histological analysis of the extracted intact worms and parasite sections from the tissue. Morphology of the filarial worms was well preserved in more than half of the cases (12/19) and there was never more than one parasite found inside the lesions. Adult worms and immature nematodes were observed in nine and seven cases, respectively. Furthermore, in two cases microfilariae were discovered inside the pseudocoelom, sections of the female reproductive tubes filled with clearly visible larval stages. Dirofilaria repens infection was diagnosed by its morphological features (17/19) or by performing polymerase chain reactions (PCR) using paraffin-embedded tissues (2/19) in the cases where the morphology was insufficient for identification and the parasites had been determined initially as Dirofilaria spp. The amplified 246 bp PCR product showed that the worms were D. repens.

Coupled tomography and distinct-element-method approach to exploring the granular media microstructure in a jamming hourglass.

We describe an approach for exploring microscopic properties of granular media that couples x-ray microtomography and distinct-element-method (DEM) simulations through image analysis. We illustrate it via the study of the intriguing phenomenon of instant arching in an hourglass (in our case a cylinder filled with a polydisperse mixture of glass beads that has a small circular shutter in the bottom). X-ray tomography provides three-dimensional snapshots of the microscopic conditions of the system both prior to opening the shutter, and thereafter, once jamming is completed. The process time in between is bridged using DEM simulation, which settles to positions in remarkably good agreement with the x-ray images. Specifically designed image analysis procedures accurately extract the geometrical information, i.e., the positions and sizes of the beads, from the raw x-ray tomographs, and compress the data representation from initially 5 gigabytes to a few tens of kilobytes per tomograph. The scope of the approach is explored through a sensitivity analysis to input data perturbations in both bead sizes and positions. We establish that accuracy of size--much more than position--estimates is critical, thus explaining the difficulty in considering a mixture of beads of different sizes. We further point to limits in the replication ability of granular flows away from equilibrium; i.e., the difficulty of numerically reproducing chaotic motion.