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To investigate the association between total leisure noise exposure and intermittent tinnitus among young adults.Data were obtained from theParticipants of theIntermittent tinnitus was reported in the majority of the sample (60%). The risk for intermittent tinnitus increased with higher sound pressure levels from exposure to leisure noise (full model (Odds Ratio, 95%CI): 80-85dB(A): 1.41 [1.13-1.78], 85-90dB(A): 1.73 [1.38-2.16],90dB(A): 2.04 [1.59-2.61]). Visiting nightclubs was a major contributor to this relationship. Of the considered covariables, self-rated hearing as "poor", and growing up in a single-parent household were significantly associated with intermittent tinnitus.Intermittent tinnitus is very frequent among young adults and is associated with high levels of leisure noise exposure. To prevent intermittent tinnitus, reduced sound pressure levels and the use of hearing protection are necessary.

Purpose: The aim of this study was to analyze the association of total leisure noise exposure and hearing threshold shifts over 5 years among adolescents enrolled in the Ohrkan cohort study. Method: The Ohrkan cohort of 2,148 students aged 13–19 years was recruited from 2009 to 2011 and followed up 5 years later. Complete baseline and follow-up reports on exposure and outcome were available for 989 participants. Leisure noise exposure was assessed by questionnaires, and clinical audiometric examinations were performed. Two outcomes were defined: occurrence of the Niskar notch pattern and audiometry showing maximum hearing threshold values at 3, 4, and 6 kHz (both ears). Longitudinal analysis using generalized estimating equations was performed. Results: High total leisure noise exposure, defined as an energy equivalent of a 40-hr week of > 85 dBA, was estimated for 32.7% of students at baseline and 63.8% at follow-up. A noise notch was observed in 1.1% of adolescents at baseline and 3.3% at follow-up. At baseline, the maximum measured threshold shift was 55 dB, which increased to 85 dB at the follow-up. Longitudinal analysis did not reveal an association between leisure noise exposure and hearing thresholds. Hearing threshold shifts or noise notches were associated with sex, school type, and time point of measurement. Conclusions: No relationship was found between leisure noise and hearing thresholds. Male adolescents and those attending secondary general schools, with graduation following completion of ninth or 10th grade, had a greater likelihood of developing hearing threshold shifts. Prevention programs should focus on these risk groups. Supplemental Material: https://doi.org/10.23641/asha.19233462

The overall objective in the study was to compare self-reported hearing based on a single question (“how good would you currently rate your hearing?”) to measure hearing loss determined by audiometry in a cohort of adolescents. Prevalence of audiometrically measured hearing loss and frequencies of self-reported poor hearing as well as factors that have an impact on self-reported hearing were examined. Baseline and 5-year follow-up data of the Ohrkan study were used. Participants filled in a questionnaire and underwent audiometric measurements. Data from 979 adolescents were analysed. Participants were 54.7% female and aged between 13 and 18 years at baseline and 17–21 years at 5-yr follow-up. The single question on self-reported hearing ability achieved a sensitivity of 41.9% and a positive predictive value of 7.1% at baseline. For the 5-yr follow-up, sensitivity was 40.0%, positive predictive value was 13.9%. Factors influencing self-reported poor hearing were gender, tinnitus, “muffled” ears after exposure to loud noise (e.g. after a concert) and low-frequency hearing loss. The single question about hearing ability used in the Ohrkan study is not sufficient to replace audiometry to detect hearing loss as defined in the study in adolescents.

Sierra Rica is a mountain island located in the plains of the northeastern region of the Chihuahua Desert and has a diversity of vegetation patterns. To study this patterns the vegetation was characterized using GIS and cluster analysis, which identified five community types: pine forest (780 ha), oak forest (1640 ha), grassland (550 ha), desert scrub (866 ha), and rosetophyllous desert scrubland (628 ha). By the use of TWINSPAN software, four main vegetation groups containing 10 main plant associations were identified: (1) Pinus-Quercus forest, (2) grassland, (3) pine forest, (4) Rhus-Juniperus, (5) Pinus-Quercus and xeric species, (6) grassland-desert scrub, (7) desert microphyll scrub, (8) Quercus-Aloysia-Bouteloua association, (9) Acacia constricta scrubland, and (10) Larrea tridentata scrubland. The association among groups and species was significant (P < 0.0001). The subsequent analysis shows a high dependence among species inside the main groups and independence between groups.

OBJECTIVE Investigating determinants of total leisure noise (TLN) exposure among adolescents over 7.5 years and compensating for missing data due to loss to follow-up. DESIGN In the OHRKAN cohort study, data were collected by questionnaires at four waves. TLN was calculated from self-reported duration spent participating in 18 leisure activities. High exposure was defined as exceeding 85 dB(A) of equivalent continuous average sound pressure level (SPL) during a 40-h week. Multiple imputation (MI) and generalised estimating equations (GEE) were used to analyse odds ratios (OR) of determinants of TLN exposure and compared to complete-case analysis. STUDY SAMPLE Closed cohort of 2148 students enrolled in grade 9 of any school in Regensburg (Germany), recruited from 2009 to 2011. RESULTS Up to 74% of adolescents had risky TLN exposure, depending on wave. The most significant sources were discotheques, portable listening devices (PLD) and stereo systems. Higher TLN exposure was associated with time point, education, single-parent households and gender. MI under MAR assumption changed results only slightly compared to complete-case analysis. CONCLUSIONS Prevalence of risky TLN is high during adolescence. MI reinforced trends detected in former results of OHRKAN. Preventive measures should consider the main drivers of noise exposure including changes by age and high risks groups.

Efforts to develop therapies against Toxoplasma reactivation have been hampered by the lack of an in vitro model of bradyzoite recrudescence. To overcome this issue, we established a new ex vivo model of bradyzoite recrudescence using bradyzoites from an unadapted Type II ME49 strain isolated from murine brain tissue to infect human foreskin fibroblasts and neonatal murine astrocytes. Bradyzoite infection of both host cell types produced two sequential tachyzoite growth stages that appeared similar to previous sporozoite in vitro infections; a fast-growing stage was followed by spontaneous formation of a slower-growing stage. In astrocytes, but not in fibroblasts, there was evidence of second bradyzoite to bradyzoite recrudescent pathway that occurred simultaneously with the bradyzoite to tachyzoite pathway. Thus, the host cell environment strongly influenced the pathway of bradyzoite recrudescence. Infections of mice with either the fast-growing or slow-growing recrudescent tachyzoites showed progressive decreases in brain cyst formation that could be fully recovered using serial tissue cyst passage demonstrating the loss of developmental capacity was reversible. By contrast, poor tissue cyst formation of laboratory-adapted tachyzoites was not reversible by these approaches indicating developmental incompetence was permanent in these strains. In order to develop methods to distinguish strain developmental competency, we identified Toxoplasma genes highly expressed in ME49EW in vivo tissue cysts and developed a qPCR approach that differentiates immature from mature bradyzoites. In summary, the results presented describe a new ex vivo bradyzoite recrudescence model that fully captures the reported growth and developmental processes observed during toxoplasmosis reactivation in vivo opening the door to the further study of these important features of the Toxoplasma intermediate life cycle.

Biodiversity positively relates with the provisioning of ecosystem services and preserving areas with elevated diversity of highly-functional species could help to ensure human well-being. Most studies addressed to make these decisions use maps relying on species occurrences, where sites containing several species are proposed as priority conservation areas. These maps, however, may underestimate species richness because of the incompleteness of occurrence data. To improve this methodology, we propose using habitat suitability models to estimate the potential distribution of species from occurrence data, and later shaping richness maps by overlapping these predicted distribution ranges. We tested this proposal with Mexican oaks because they provide several ecosystem services and habitat suitability models of species were calibrated with MaxEnt. We used linear regressions to compare the outputs of these predictive maps with those of maps based on species occurrences only and, for both mapping methods, we assessed how much surface of sites with elevated richness and endemism of oaks is currently included within nature reserves. Both mapping methods indicated that oak species are concentrated in mountain regions of Mexico, but predictive maps based on habitat suitability models indicated higher oak richness and endemism that maps based on species occurrences only. Our results also indicated that nature reserves cover a small fraction of areas harboring elevated richness and endemism of oaks. These results suggest that estimating richness across extensive geographic regions using habitat suitability models quickly provides accurate information to make conservation decisions for highly-functional species groups.

Bird migration constitutes a redistribution of bird diversity that radically changes the composition of the bird community worldwide. It comprises about 19% of the world’s bird species. Several studies have indicated that changes in avian community structure and differences in bird richness in different seasons are mainly driven by seasonality and by winter harshness, and that the associated costs increase with the distance involved. Western Mexico is an important wintering area for most passerines that breed in western North America, and that travel long on the long-distance Central and Pacific migration routes. In this study, we examined bird species richness and diversity during the breeding and wintering seasons in the Central Sierra Madre Occidental (SMO), North Durango (Mexico) in relation to i) tree species diversity, ii) tree dimension, iii) forest stand density and site quality, iv) density and dimension of snag trees, and v) various climate variables. The overall aim of the study was to determine how the observed associations between bird species diversity and variables i-v are affected by the season considered (breeding or wintering). The diversity of bird species in the breeding season was not affected by any of the climate and forest stand variables considered. In contrast, bird species diversity in the wintering season was significantly and weakly to moderately associated with climate variables, tree species diversity and stand density, although not with density or dimension of snag trees. Bird species diversity was higher at lower elevations and in drier and warmer locations of the SMO. The association detected is therefore mainly a local migratory phenomenon.

Background: Studies investigating leisure noise effect on extended high frequency hearing are insufficient and they have inconsistent results. The aim of this study was to investigate if extended high-frequency hearing threshold shift is related to audiometric notch, and if total leisure noise exposure is associated with extended high-frequency hearing threshold shift. Materials and Methods: A questionnaire of the Ohrkan cohort study was used to collect information on demographics and leisure time activities. Conventional and extended high-frequency audiometry was performed. We did logistic regression between extended high-frequency hearing threshold shift and audiometric notch as well as between total leisure noise exposure and extended high-frequency hearing threshold shift. Potential confounders (sex, school type, and firecrackers) were included. Results: Data from 278 participants (aged 18–23 years, 53.2% female) were analyzed. Associations between hearing threshold shift at 10, 11.2, 12.5, and 14 kHz with audiometric notch were observed with a higher prevalence of threshold shift at the four frequencies, compared to the notch. However, we found no associations between total leisure noise exposure and hearing threshold shift at any extended high frequency. Conclusion: This exploratory analysis suggests that while extended high-frequency hearing threshold shifts are not related to total leisure noise exposure, they are strongly associated with audiometric notch. This leads us to further explore the hypothesis that extended high-frequency threshold shift might be indicative of the appearance of audiometric notch at a later time point, which can be investigated in the future follow-ups of the Ohrkan cohort.

Agriculture is one of most important economic activities that requires large amounts of water, which, in addition to changes in climate, presents a major impact on the water availability. Excess of salt and nutrient concentrations build up damages to soil such as reduced drainage and increase in anoxic conditions in the root zone, as well as decreasing productivity and usable farm lands. The objective of the present study was to evaluate the chemical vulnerability of an aquifer in arid conditions with a high level of extraction through the detection of risk zones and potential subregions of different risks. An evaluation of the quality of the groundwater was performed, as a reconnaissance prior to more detailed studies, in which samples of 30 wells were analyzed to determine physical-chemical parameters (recorded in situ), dissolved chemical species (UV–vis spectrophotometry), and elemental content (X-ray fluorescence spectrophotometry). Concentrations of TDS, as well as Ca, Mg, S, Cl, and As determined in the water under analysis exceeded the limit established for water for consumption and irrigation. It is suggests that the origin of the elemental composition is mainly due to the mineral composition of the aquifer sediments. The wells were classified in three groups located in different zones, based on: a) alkaline earth elements, b) halogens, c) dissolved ions. Water salinity is mainly composed by sulphates and, a lesser extent, by hydrochloric salts from leaching of evaporites. Furthermore, the highest chemical vulnerability are located from central to north zone, where the soils showed crop leaching requirement by above of threshold value for pecan crops, one of the major agricultural products of the valley. In conclusion, both the salinity and the high level of water extraction for agriculture, combined with the arid conditions, are provoking an increase in contents of some chemical species in soil of crops. The immediate consequences are related to a reduction in the agricultural production and, therefore, a decrease in the productive competitiveness.

The aim was to investigate leisure noise exposure and sociodemographic determinants of risky leisure noise exposure over five years in 2148 students visiting grade 9 of any school type in a German city from 2009-2011. Within the OHRKAN cohort study, leisure noise exposure was calculated from literature-retrieved sound pressure levels (SPLs) and self-reported duration of 18 leisure activities at baseline and two follow-ups. Risky exposure was defined as exceeding 85 dB(A) averaged over a 40-h-week. Determinants of risky total leisure noise (TLN) exposure and risky exposure to portable listening devices (PLDs) were investigated using generalised estimating equations (GEEs). Up to 73% of students exceeded noise levels of 85 dB(A) at some timepoint. The noise exposure and importance of different leisure activities changed with increasing age. Risky exposure to TLN and PLDs was associated with lower education, single parent households and being male. Risky PLD exposure was additionally associated with a migrant background. Current prevention measures for leisure noise exposure must be extended to at-risk groups. Besides enhancing campaigns in lower education schools, acoustical insulation in sports halls, noise warnings on tools or in videogames could address especially men. Migrants need education about healthy PLD use in their native language if necessary.

Determining ionizing radiation in a geographic area serves to assess its effects on a population's health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h(-1). At the same sites, 48 soil samples were taken to obtain the activity concentrations of (226)Ra, (232)Th and (40)K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h(-1). Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg(-1), for (226)Ra, (232)Th and (40)K, respectively. From the analysis, the spatial distribution of (232)Th, (226)Ra and (40)K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize.

Fast land use changes have strongly affected arid and semi-arid regions at a global scale, affecting food security of the inhabitants of these regions. This study evaluated the fragmentation degree in the Chihuahua´s desert region of Mexico by using data from the Landsat TM sensor. Nine scenes, taken with Landsat TM5 sensor from the years 1990, 2000, and 2012, were used for the analysis. The coverage of seven land uses (grasslands, shrubland, croplands, sandy desert vegetation, forest, water bodies, and urban areas) was obtained under supervised classification techniques and the accuracy level was evaluated through the Kappa multi-varied discrete index. The classification showed a good reliance level having global accuracies of 93, 93.2 and 90.3% for the years 1990, 2000 and 2012, respectively. The fragmentation analysis showed an increase in the number of patches, an indicator of the ecosystem degradation process. The patches number increased from 8,354.23 in 1990 to 9,658.36 in 2000 and to 11,4...

Objective: To investigate total leisure noise exposure among adolescents and to assess its association with hearing. Design: Based on self-reported time spent on 19 leisure activities and associated mean sound pressure levels reported in the literature, total leisure noise exposure was evaluated and compared to noise at work limits (> 85 dB(A) = hazardous) in a cross-sectional survey. Tympanometry and pure-tone audiometry was performed in sound isolated rooms. Study sample: The study sample consists of 2143 pupils attending grade nine in any school in a German city 2009–2011 (mean age: 15.4 years; range: 13–19 years). Audiometric data were available for 1837 (85.8%) pupils (53.9% girls). Results: 41.9% of the 2143 adolescents who had provided self-reported data on leisure activities associated with noise exposure were estimated to be hazardously exposed to leisure time noise. The interaction of gender with total leisure time noise exposure was not significant. No association between leisure time noise exposure and audiometric notches could be detected. Conclusion: While hearing loss seems seldom in this age group, a high proportion of adolescents aged 15–16 years are exposed to noise levels during leisure time bearing long-term risks of hearing loss.

Species distribution models (SDMs) help identify areas for the development of populations or communities to prevent extinctions, especially in the face of the global environmental change. This study modeled the potential distribution of the tree Picea chihuahuana Martínez, a species in danger of extinction, using the maximum entropy modeling method (MaxEnt) at three scales: local, state and national. We used a total of 38 presence data from the Sierra Madre Occidental. At the local scale, we compared MaxEnt with the reclassification and overlay method integrated in a geographic information system. MaxEnt generated maps with a high predictive capability (AUC &gt, 0.97). The distribution of P. chihuahuana is defined by vegetation type and minimum temperature at national and state scales. At the local scale, both models calculated similar areas for the potential distribution of the species, the variables that better defined the species distribution were vegetation type, aspect and distance to water flows. Populations of P. chihuahuana have always been small, but our results show potential habitat greater than the area of the actual distribution. These results provide an insight into the availability of areas suitable for the species’ regeneration, possibly through assisted colonization.

The methods for measuring vegetation cover in Mexican forest surveys are subjective and imprecise. The objectives of this research were to compare the sampling designs used to measure the vegetation cover and estimate the over and understory cover in different land uses, using digital photography. The study was carried out in 754 circular sampling sites in central Mexico. Four spatial sampling designs were evaluated in three spatial distribution patterns of the trees. The sampling designs with photographic captures in diagonal form had lower values of mean absolute error (MAE < 0.12) and less variation in random and grouped patterns. The Carbon and Biomass Sampling Plot (CBSP) design was chosen due to its smaller error in the different spatial tree patterns. The image processing was performed using threshold segmentation techniques and was automated through an application developed in the Python language. The two proposed methods to estimate vegetation cover through digital photographs were robust and replicable in all sampling plots with different land uses and different illumination conditions. The automation of the process avoided human estimation errors and ensured the reproducibility of the results. This method is working for regional surveys and could be used in national surveys due to its functionality.

Ore mining has served as a predictor of economic wellbeing since it brought development to countries. However, these benefits do not always extend to all localities that comprised the center of this industry. This paper examined the contribution of mining to local communities. An index of local sustainability was constructed based on economic, social, and land-use data from twelve localities where mining and forestry are their major economic activities. Land-use variables were obtained from Landsat Thematic Mapper (TM 5) images for 2000, and Landsat Operational Land Imager (OLI8) for 2014, while the socio-economic variables were collected in twelve localities with an 85-question survey. A sustainability index was developed for each group of variables—economic (ESI), social (SSI) and land-use sustainability index (LUSI)—to further build a local sustainability index (LSI). Three localities showed the highest ESI (0.61, 0.53 and 0.43) and SSI (0.90, 0.79 and 0.78), while two localities had the lowest values in the ESI and SSI. In contrast, the highest value of LUSI was found in two other different localities and in one with lower SSI. Income from mining activities is positively associated with the ESI and SSI, but there was no evidence of linear association with the LUSI. A local index of sustainability provides useful information for planning and development strategies.

The unusual cell cycles of Apicomplexa parasites are remarkably flexible with the ability to complete cytokinesis and karyokinesis coordinately or postpone cytokinesis for several rounds of chromosome replication, and are well recognized. Despite this surprising biology, the molecular machinery required to achieve this flexibility is largely unknown. In this study, we provide comprehensive experimental evidence that apicomplexan parasites utilize multiple Cdk-related kinases (Crks) to coordinate cell division. We determined that Toxoplasma gondii encodes seven atypical P-, H-, Y- and L- type cyclins and ten Crks to regulate cellular processes. We generated and analyzed conditional tet-OFF mutants for seven TgCrks and four TgCyclins that are expressed in the tachyzoite stage. These experiments demonstrated that TgCrk1, TgCrk2, TgCrk4 and TgCrk6, were required or essential for tachyzoite growth revealing a remarkable number of Crk factors that are necessary for parasite replication. G1 phase arrest resulted from the loss of cytoplasmic TgCrk2 that interacted with a P-type cyclin demonstrating that an atypical mechanism controls half the T. gondii cell cycle. We showed that T. gondii employs at least three TgCrks to complete mitosis. Novel kinases, TgCrk6 and TgCrk4 were required for spindle function and centrosome duplication, respectively, while TgCrk1 and its partner TgCycL were essential for daughter bud assembly. Intriguingly, mitotic kinases TgCrk4 and TgCrk6 did not interact with any cyclin tested and were instead dynamically expressed during mitosis indicating they may not require a cyclin timing mechanism. Altogether, our findings demonstrate that apicomplexan parasites utilize distinctive and complex mechanisms to coordinate their novel replicative cycles., Author summary Apicomplexan parasites are unicellular eukaryotes that replicate in unusual ways different from their multicellular hosts. From a single infection, different apicomplexans can produce as few as two or up to many hundreds of progeny. How these flexible division cycles are regulated is poorly understood. In the current study we have defined the major mechanisms controlling the growth of the Toxoplasma gondii acute pathogenic stage called the tachyzoite. We show that T. gondii tachyzoites require not only multiple protein kinases to coordinate chromosome replication and the assembly of new daughter parasites, but also each kinase has unique responsibilities. By contrast, the mammalian cell that T. gondii infects requires far fewer kinase regulators to complete cell division, which suggests that these parasites have unique vulnerabilities. The increased complexity in parasite cell cycle controls likely evolved from the need to adapt to different hosts and the need to construct the specialized invasion apparatus in order to invade those hosts.

Apicomplexa division involves several distinct phases shared with other eukaryote cell cycles including a gap period (G1) prior to chromosome synthesis, although how progression through the parasite cell cycle is controlled is not understood. Here we describe a cell cycle mutant that reversibly arrests in the G1 phase. The defect in this mutant was mapped by genetic complementation to a gene encoding a novel AAA-ATPase/CDC48 family member called TgNoAP1. TgNoAP1 is tightly regulated and expressed in the nucleolus during the G1/S phases. A tyrosine to a cysteine change upstream of the second AAA+ domain in the temperature sensitive TgNoAP1 allele leads to conditional protein instability, which is responsible for rapid cell cycle arrest and a primary defect in 28S rRNA processing as confirmed by knock-in of the mutation back into the parent genome. The interaction of TgNoAP1 with factors of the snoRNP and R2TP complexes indicates this protein has a role in pre-rRNA processing. This is a novel role for a cdc48-related chaperone protein and indicates that TgNoAP1 may be part of a dynamic mechanism that senses the health of the parasite protein machinery at the initial steps of ribosome biogenesis and conveys that information to the parasite cell cycle checkpoint controls.

Objective: To describe personal music player (PMP) usage among adolescents, sociodemographic determinants and association with audiometric notches. Design: Audiometric evaluation to assess hearing status, and standardized questionnaires to evaluate PMP listening behaviors, leisure noise exposures and self-reported hearing loss symptoms. Sociodemographic information was collected using a parent questionnaire. Noise exposure by PMP usage equivalent for a 40h week was estimated based on self-reported volume and duration of use. Study sample: A total of 2143 students (54% females) attending 9th grade in Regensburg, Germany, during 2009 to 2011. Results: Overall, 85% of the students reported using PMPs. Exposure level exceeded 80dB(A) in approximately one third, and 85dB(A) in one quarter, of those who used PMP. An audiometric notch was found in 2.3% of participants, but was not significantly associated with higher PMP exposure. Conclusions: PMP exposure above the occupational limits of 80 and 85dB(A) set by the Directive 2003/10/EC may be a risk factor for developing noise-induced hearing loss. Educational measures to ameliorate high risk behaviors in PMP usage are needed, particularly for socially disadvantaged groups.

Introduction: Exposure to high continuous noise during leisure activities such as attending discotheques or listening to portable listening devices at high volume levels is presumed to have harmful...

The spatio-temporal analysis of land use changes could provide basic information for managing the protection, conservation and production of forestlands, which promotes a sustainable resource use of temperate ecosystems. In this study we modeled and analyzed the spatial and temporal dynamics of land use of a temperate forests in the region of Pueblo Nuevo, Durango, Mexico. Data from the Landsat images Multispectral Scanner (MSS) 1973, Thematic Mapper (TM) 1990, and Operational Land Imager (OLI) 2014 were used. Supervised classification methods were then applied to generate the land use for these years. To validate the land use classifications on the images, the Kappa coefficient was used. The resulting Kappa coefficients were 91%, 92% and 90% for 1973, 1990 and 2014, respectively. The analysis of the change dynamics was assessed with Markov Chains and Cellular Automata (CA), which are based on probabilistic modeling techniques. The Markov Chains and CA show constant changes in land use. The class most affected by these changes is the pine forest. Changes in the extent of temperate forest of the study area were further projected until 2028, indicating that the area of pine forest could be continuously reduced. The results of this study could provide quantitative information, which represents a base for assessing the sustainability in the management of these temperate forest ecosystems and for taking actions to mitigate their degradation.

Background Injection laryngoplasty is an option for treatment of dysphonia following vocal fold paralysis. Modified fibrin glue with suspended chondrocytes might be a favorable cell-based material for permanent vocal fold medialization. Methods We compared fibrin glue with suspended chondrocytes to collagen and hyaluronic acid gels concerning alteration of vocal fold vibration and correct intralaryngeal placement after intralaryngeal injection into porcine larynges. Viscoelastic properties of the materials were analyzed by means of a parallel plate rheometer. Results Fibrin glue with cells was comparable to collagen and hyaluronic acid with respect to amplitudes, symmetry, and periodicity of vocal fold vibration. Application and positioning of fibrin glue with suspended chondrocytes were technically undemanding and comparable with controls. Complex stress modulus of fibrin glue with suspended cells was comparable to that of collagen gel. Conclusions Fibrin glue with suspended chondrocytes seems suitable for the indication of injection laryngoplasty and holds promise for permanent vocal fold medialization. © 2011 Wiley Periodicals, Inc. Head Neck, 2012

The aim of this study was to quantify major and trace elements in the water, soil, and plants (Carya illionensis) in an agricultural area, and to determine the health risks associated with the walnuts ingestion by calculating the risk quotient. Samples of water, soil, tree leaves, and walnuts were collected, in total, 135 samples were analyzed. Physicochemical parameters were obtained in irrigation water and soil samples. Elemental measurements were performed in an ICP, -OES and -MS. In addition, the distribution coefficient (soil&ndash, water), transfer factor (soil&ndash, plant), and hazard quotient were evaluated. In the irrigation water, As, Cr, and Pb, showed concentrations above the maximum allowable limits. Likewise, high concentrations of As, Cr, Pb, and Sb were found in tree leave samples, indicating a possible tendency of hyperaccumulation of those elements. Furthermore, Cr concentrations in walnuts were high by far than the reference value (FAO/WHO). A possible competition between chemical congeners were detected from transfer factors. Although, Sb concentrations in walnuts were also high, and no legislation for it in fruits exists. The hazard risk quotient for Sb did indicate a potential health risk. Finally, it is important to consider that the health risk increases when exposure through consumption takes place over a prolonged period of time, even in low concentrations.

We analyse committees of voters who take a decision between two options as a two- stage process. In a discussion stage, voters share non-verifiable information about a private signal concerning what is the best option. In a voting stage, votes are cast and one of the options is implemented. We introduce the possibility of leadership whereby a certain voter, the leader, is more influential than the rest at the discussion stage even though she is not better informed. We study information transmission and characterize the effects of the leader on the deliberation process. We find, amongst others, that both the quality of the decision taken by the committee and how truthful voters are at the discussion stage depends non-monotonically on how influential the leader is. In particular, although a leader whose influence is weak does not disrupt the decision process of the committee in any way, a very influential leader is less disruptive than a moderately influential leader.

Background: While noise exposure at the workplace is regulated to minimize the risk of hearing loss, leisure noise exposure is likely to pose a risk for hearing as well. However, valid recent data ...

Follicular dendritic cells (FDC) are located within the B-cell follicles of non-malignant lymphatic tissues and within non-Hodgkin-lymphomas (NHL) derived from the germinal centre or the mantlezone. The interactions between FDC and non-neoplastic B-cells have been extensively investigated but so far no data on functional studies with FDC isolated from lymphoma tissue are available. Using an enzyme cocktail to digest lymph nodes from patients with NHL followed by density centrifugation, single cell suspensions enriched in FDC and B-lymphocytes were obtained. In these preparations FDC formed small cellular clusters with an average of five neoplastic lymphocytes for every FDC. Immunocytochemistry with Ki67 revealed that after 24 h of culture 23.7% of the cells within the clusters were in late G1 to M phase. In contrast, only 10.2% of the lymphoma cells scattered outside the clusters were in these activated stages. As visualized by autoradiography, after 72 h of incubation the rate of proliferation was 16.8 times higher for the lymphoma cells involved in cluster formation as compared to those lymphocytes not associated with FDC. The data indicate that in vitro FDC from NHL lymph nodes form a microenvironment favourable for the activation and proliferation of lymphoma cells. The search for cytokines secreted by FDC in lymphoma tissue is under way.

In secondary lymphoid organs, follicular dendritic cells (FDC) are located within B cell follicles and germinal centers. Through their cytoplasmic extensions they come into contact with a large number of neighboring lymphocytes. Using an enzyme cocktail to digest human tonsils followed by ultracentrifugation on bovine serum albumin gradients, single cell suspensions were obtained. Immunocytochemistry revealed that 7% of the cells were FDC, 5% T cells, and 5% macrophages. The remaining population were B cells with greater than 95% being of the germinal center phenotype (i.e. CD19-positive, CD39/sIgD negative). After 24 h of culture up to 44% of the lymphocytes were found in clusters centered around FDC. At the start of the culture as well as 24 and 72 h later, between 31 and 55% of the B cells within FDC associated clusters were in late G1 to M phase of the cell cycle. In contrast, less than 10% of the B cells not in contact with FDC (i.e. outside the clusters) were in an activated state. Autoradiography revealed that after three days of incubation the rate of proliferation was 26.2 times higher for the lymphocytes involved in cluster formation as compared to those cells not associated with FDC. Furthermore, the number of viable B cells after a 72 h mitogen-free culture period was determined. By adding FDC to these preparations, 31.9% of the lymphocytes were rescued from dying. These data show that FDC provide a microenvironment which can maintain the viability, activation and proliferation of germinal center B cells in vitro.

Context: Distortion product otoacoustic emissions (DPOAEs) may indicate preclinical noise-induced hearing loss (NIHL) in adolescents from unsafe personal music player (PMP) use. Aims: The objective, therefore, was to observe preclinical signs of NIHL in 9th grade adolescents with clinically normal hearing by comparing DPOAE signals between different levels of A-weighted equivalent PMP exposure. Settings and Design: Subjects were recruited from all secondary-level schools located in the city of Regensburg, Germany during two academic years 2009/2010 and 2010/2011. Subjects and Methods: A-weighted equivalent sound pressure levels (SPLs) for a 40-hour work week (LAeq,40h) were estimated from questionnaire responses on output and duration of PMP use of the previous week. Subjects were then categorized into four levels of exposure: 85 to

Although there is concern about increasing hearing loss in adolescents caused by leisure noise exposure, prevalence data are scarce. In an US study, about 16-17% of adolescents were affected by audiometric notches. To estimate the prevalence of audiometric notches in adolescents in Germany, baseline data of the cohort study Ohrkan, recruitment during the school years 2009/2010 and 2010/2011 were analyzed. All students in grade 9 visiting any school in the city of Regensburg were eligible for participation. Data was collected via standardized questionnaires from students and their parents. In addition, students were asked to visit the University Clinics of Regensburg for ear examination including a tympanogram and the determination of hearing thresholds in air conduction audiometry. The prevalence of audiometric notches was determined in students with normal tympanogram in both ears and complete audiometry data. Audiometric notches were defined according to criteria used to analyse US data. Overall, 2149 students (1158 girls, 991 boys mainly aged 15-16 years) of the 3846 eligible adolescents (56%) participated. Among the 1843 adolescents with complete audiometry and tympanometry data, the prevalence of audiometric notches was 2.4% (95% confidence interval 1.7-3.1%). We could not confirm the high prevalence of audiometric notches as reported in National Health and Nutrition Examination Surveys for adolescents in the US. Differences in prevalence might be at least partly due to methodical differences in audiometry. Even if empirical evidence is presently ambiguous, it is reasonable to educate young people about the potential risks of high leisure noise exposure.

Follicular dendritic cells (FDC) are located within follicles of secondary lymphoid tissue and in lymph nodes of patients with germinal center cell-derived non-Hodgkin lymphomas. Reliable antigenic phenotyping of FDC within tissue sections has been difficult due to simultaneous labeling of the surrounding germinal center cells. Using an enzyme cocktail to digest human tonsils and cervical lymph nodes with subsequent fractionation by albumin gradient centrifugation, cell isolates containing up to 20% FDC were obtained. This preparation allowed the determination of antigenic phenotype on individual FDC. Molecules expressed by FDC were detected by an isotype-specific immunocytochemical double-labeling procedure, i.e. a monoclonal antibody (mAb) specific for FDC (KiM4 or DRC1) in conjunction with a mAb reactive against an additional antigenic determinant. Nonspecific binding of mAb to immunoglobulin Fc receptors located on FDC membranes was avoided by incubation of cells with human IgG aggregates prior to immunostaining. The results revealed that isolated FDC from these lymphoid tissues express transferrin receptors, the intercellular adhesion molecule 1, class II antigens, the B cell antigens CD20 and CD21, and the myelomonocytic properties CD11b and CD14. Immunoglobulin mu or gamma heavy chains and the B cell antigens CD23 and CD24 are detected on 50% of an isolated FDC population. These FDC are negative for the T helper cell antigen CD4, the B cell cell antigens CD19 and CD22, the immunolobulin alpha and delta chains and the S-100 protein. FDC isolated from lymph nodes of patients with low-grade malignant non-Hodgkin lymphoma, identified by DRC1 or KiM4 mAb, presented the same antigenic profile as seen on FDC from nonmalignant tissue. This suggests that FDC from lymphoma tissue isolated in this manner have the same properties as those found in normal tissue.

We analyze simple coalition formation problems in which a group of agents is partitioned into coalitions and agents' preferences only depend on the identity of the members of the coalition to which they belong. We study coaltion formation rules that associate to each profile of agents'' preferences a partition of the group of agents. Assuming that agents'' preferences are separable, we show that no coalition formation rule can satisfy the joint requirements of strategy-proofness, individual rationality, non-bossiness, and voters'' sovereignty.