Urbanization affects in-stream biogeochemical processes that control nutrient export. Attempts to restore urban streams will not be successful unless the biological and physical controls on water quality are thoroughly understood. The objective of this study was to identify the relative influences of tributary dilution, groundwater discharge, and biological processing on nitrate concentrations in an urban stream during high and low flow periods. A wastewater treatment plant (WTP) on Pennypack Creek, an urban stream near Philadelphia, PA, increases nitrate concentrations to a mean of 8.5 mg-l-1 (as N). Concentrations decrease to 5.5 mg-l-1 about 7.5 km downstream. Reaches along this distance were sampled for nitrate concentration and delta-15N at fine spatial intervals to determine the reasons for this decrease. To quantify the effects of dilution, samples were collected from tributaries, groundwater springs, and upstream and downstream of tributaries or groundwater discharge zones identified through terrain analysis and continuous temperature modeling. These methods were also used to identify and sample reaches along which hyporheic flow occurred, where nitrate biological processing is often concentrated. In addition, loggers were installed at closely spaced sites to monitor daily fluctuations in nitrate, dissolved oxygen, and related parameters, which provided further indications of biological processing. Longitudinal sampling revealed decreases in nitrate concentration of 2 and 6.5 mg-l-1 during high and low flow, respectively. During high flow, delta-15N varied from 9.5 to 10.5 per mille downstream of the WTP, while delta-15N varied from 10.14 to 11.06 per mille throughout this reach during low flow. Mixing analysis indicated that groundwater discharge and biological processing both control nitrate concentration during both flow periods. Larger declines in nitrate concentration were observed during low flow than during high flow, and delta-15N fell between biological and groundwater signatures, indicating that both processes were enhanced. Continuous nitrate concentrations displayed distinct diurnal cycles often out-of-phase with dissolved oxygen cycles, indicating autotrophic processing. However, shifts occurred in nitrate cycle timing at a weekly scale wherein daily maximum concentrations were observed as many as 6 hours closer to noon than previously. These shifts were comparable to shifts observed across seasons in other studies, and by the end of the summer, nitrate and dissolved oxygen cycles were in-phase. Furthermore, shifts in nitrate cycles could not be linked to shifts in daily fluctuations of WTP discharge. Longitudinal sampling and continuous monitoring suggest that biological processing is an important control on nitrate concentrations in urban systems, though documenting its signature may be complicated by groundwater discharge and anthropogenic inputs. / Geology

Spatial and temporal variation in foliar gas exchange on both a diurnal and seasonal scale was examined in 15-year-old fertilized and non-fertilized loblolly pine in the upper and lower thirds of crowns in stands located in the North Carolina sandhills. Photosynthesis rates between control and fertilized stands for both seasonal and diurnal measurement periods were different during only three months. Photosynthesis rates were consistently greater in the upper third of the crown compared to the lower third. Seasonal trends in both conductance and transpiration closely resembled trends found in seasonal photosynthesis. Foliar nitrogen concentrations were greater in fertilized stands for all months sampled. However, nitrogen content generally did not correlate with photosynthesis rates. Mean monthly water use efficiencies were significantly higher in fertilized stands during two months and were usually greater in upper crown foliage. Common empirical gas exchange models reveal that light and vapor pressure deficit (VPD) explain a majority of the variation observed in photosynthesis and transpiration, respectively. Conductance was not modeled since environmental variation did not adequately explain conductance patterns. Predicted light response curves reveal that upper crown foliage has higher maximum photosynthesis rates, respiration rates, light compensation points, and lower initial quantum yield compared to lower crown foliage. Models predict that foliage from fertilized stands is more sensitive to VPD and light during the growing season. Transpiration models predict highly variable responses to VPD depending on the treatment combination and season. Model R-square and predicted gas exchange values suggest that seasonal acclimation occurred. / Master of Science

Yes / The WNT pathway was shown to play an important role in the adult central nervous system. We previously identified the WNT pathway as a novel integration site of the adipokine leptin in mediating its neuroendocrine control of metabolism in obese mice. Here we investigated the implication of WNT signaling in seasonal body weight regulation exhibited by the Djungarian hamster (Phodopus sungorus), a seasonal mammal that exhibits profound annual changes in leptin sensitivity. We furthermore investigated whether crucial components of the WNT pathway are regulated in a diurnal manner. Gene expression of key components of the WNT pathway in the hypothalamus of hamsters acclimated to either long day (LD) or short day (SD) photoperiod was analyzed by in situ hybridization. We detected elevated expression of the genes WNT-4, Axin-2, Cyclin-D1, and SFRP-2, in the hypothalamic arcuate nucleus, a key energy balance integration site, during LD compared with SD as well as a diurnal regulation of Axin-2, Cyclin-D1, and DKK-3. Investigating the effect of photoperiod as well as leptin on the activation (phosphorylation) of the WNT coreceptor LRP-6-(Ser1490) by immunohistochemistry, we found elevated activity in the arcuate nucleus during LD relative to SD as well as after leptin treatment (2 mg/kg body weight). These findings indicate that differential WNT signaling may be associated with seasonal body weight regulation and is partially regulated in a diurnal manner in the adult brain. Furthermore, they suggest that this pathway plays a key role in the neuroendocrine regulation of body weight and integration of the leptin signal.

Reproduction ability is the key factor for survival and dispersal of every species. There is, however, only limited information about reproduction of large-bodied fish. Males of European catfish, our biggest native fish, build nests in vegetation and mate there later with females. After succesful mating male guards the nest and takes care of eggs and fry. According to literature, the act of reproduction should take place at nights with water temperature from 18 to 24 řC. However, available records about reproductive behaviour are outdated, fragmentary or come from aquacultures. Thus, a study was designed to evaluate behaviour of European catfish in their natural environment in the Berounka river using radiotelemetry, the results of which I processed in this thesis. Spatial distribution of catfish was followed during the whole year, with special attention on separating mating season from the rest of the year. The goal was to determine conditions characteristic for the mating period and to verify that catfish in the field indeed reproduce in pairs. For this purpose, 10 adults were tracked for two-year period (2002-2004) in the Berounka river by radiotelemetry. Exact positions of all individuals were followed in fourteen-day cycles. In every tracking episode, the position of an individual fish was...

Contexte et objectif – Les patients âgés gonarthrosiques présentent une dégradation du contrôle postural. Les méthodes non pharmacologiques sont aujourdhui recommandées comme option de première intention dans la gestion de l’arthrose. L’hydrothérapie fait partie des moyens de rééducation à disposition des patients âgés atteints d’arthrose du genou pour ses effets antalgiques et musculaires. Cependant, peu d’études sont actuellement disponibles concernant l’effet de l’hydrothérapie sur le contrôle postural, associée ou non à des programmes de rééducation individuels ciblés. Par ailleurs, le contrôle postural est susceptible de variations diurnes. Cette étude a eu pour objet de décrire le contrôle postural des personnes gonarthrosiques à quatre périodes de la journée, puis de comparer l’amélioration du contrôle postural au cours de deux programmes de rééducation différents recourant à l’hydrothérapie. Matériel et méthodes - Deux-cent-quatre-vingt quatre patients souffrant d’arthrose du genou ont été inclus dans cette étude. Le bilan posturographique a été réalisé une semaine avant la cure thermale en condition simple (yeux ouverts, support stable) et en conditions sensorielles contradictoires (vision faussée ou indisponible, proprioception perturbée). Pour évaluer les variations diurnes de la stabilité posturale, les patients ont été randomisés à quatre périodes d’essai dans la journée définies comme suit : 8h-10h, 10h-12h, 13h-15h, 15h-17h. L’influence du sexe, de l’âge, de la taille, du poids et de l’indice de masse corporelle sur la stabilité posturale a été évaluée. La gonalgie a également été évaluée à quatre périodes d’essai. Par la suite, les patients ont été randomisés en deux groupes de rééducation différents pour recevoir des traitements aquatiques : groupe cure classique (hydrothérapie efficace prouvée, c’est-à-dire groupe témoin) et groupe cure active (hydrothérapie combinant des programmes de réhabilitation individuels ciblés). Les bilans de posturographie statique ont été réalisés respectivement à 21 jours, 42 jours et 90 jours après le début de l’hydrothérapie. Résultats –Les tests posturographiques ont été réalisés chez 241 patients (âge moyen : 64,8 + 8,7 ans ; 82 hommes). Le contrôle de l’équilibre était plus efficace l’après-midi que le matin à la fois dans les conditions simple (p = 0,012) et sensorielle contradictoire (p = 0,047), en particulier en début d’après-midi lorsque la vision et la proprioception étaient disponibles (p = 0,026) ou perturbées (p = 0,019). La gonalgie a été plus prononcée le matin que l’après-midi (p < 0,001). La variation diurne du contrôle postural était plus marquée chez les patients plus âgés, de poids plus élevé, de sexe masculin, dans les conditions d’essais différentes (p < 0,05). Les deux cures d’hydrothérapie ont eu des effets curatifs considérables sur la restauration du contrôle de l’équilibre. Une meilleure précision des oscillations posturales a été constatée dans le groupe cure active par rapport au groupe cure classique, 42 jours après le début de l’hydrothérapie (p = 0,020), en particulier lorsque la proprioception a été perturbée avec (p = 0,028) ou sans (p = 0,025) vision disponible. Dans les deux groupes a été observée une stabilité posturale comparable dans un délai de trois mois. Conclusions - Cette étude a montré une meilleure stabilité posturale chez les patients atteints d’arthrose du genou, en début d’après-midi par rapport à la fin de matinée dans les situations sensorielles simples ou contradictoires. Il a été constaté que ces variations étaient également liées à l’âge, au sexe, au poids et pourraient être expliquées par la douleur articulaire fluctuante dans la journée. Considérée comme un traitement non pharmacologique applicable et recommandé, l’hydrothérapie est bénéfique à l’amélioration de la stabilité posturale chez les patients âgés atteints d’arthrose du genou, en particulier combinant un programme de réhabilitation individuel ciblé. [...] / Background and Objective – Increasing evidence supports balance control impairment in elderly patients with knee osteoarthritis (OA). Current guidelines recommend non-pharmacologic methods as first-line options in the management of OA. Hydrotherapy is a beneficial training medium for rehabilitation in elderly knee OA patients. However, few indications at present are available concerning the effect of hydrotherapy combining with targeted individual rehabilitation programs to improve balance control. Meanwhile, there is limited data on diurnal variation of balance control in these patients. This study aimed to investigate postural stability in elderly patients with symptomatic knee OA during different periods in a daytime before the spa therapy, then to study the results obtained before and after hydrotherapy to compare the improvement of balance control in these patients in two different water-based rehabilitation programs. Materials and Methods – Two-hundred and eighty-four knee OA patients were enrolled in this study. Static posturography using a vertical force platform was performed one week before spa therapy in simple (eyes open, firm support) and conflicting sensory (vision altered or unavailable, proprioception altered) conditions. To assess diurnal postural variations, patients were randomized to four testing sessions in a daytime defined as follows: 8-10am, 10-12am, 1pm-3pm, 3pm-5pm. Influence of sex, age, height, weight, and body mass index on postural stability was evaluated. Knee pain was also assessed in four testing sessions. Patients were then randomized to two different rehabilitated groups to receive spa therapies. Classic treatment group as a control received the efficacy proven spa water therapy, and active treatment group received spa water therapy combining with targeted individual rehabilitation programs. Static posturographies were carried out respectively in 21 days, 42 days and 90 days after the beginning of hydrotherapy. Results – Posturographic tests were completed for 241 patients (mean age: 64.8 + 8.7 years; 82 males). Balance control was more efficient in the afternoon than in the morning both in simple (p = 0.012) and conflicting sensory conditions (p = 0.047), especially in early afternoon when vision and proprioception were available (p = 0.026) or disturbed (p = 0.019). Patients’ knee pain was more pronounced in the morning than in the afternoon (p < 0.001). Diurnal variation of balance control was more noticeable in older, heavier, and male patients under different testing conditions (p < 0.05). Both the water-based therapies had considerable curative effect on balance control restoration. Better postural sway precision were found in active group than classic group 42 days after the beginning of hydrotherapy (p = .020), especially when proprioception was interfered with (p = .028) or without (p = .025) an available vision. Both of the groups have been observed a comparable postural stability in a three-month term. Conclusions – This study showed that better postural stability was observed in patients with knee OA in early afternoon than in late morning in simple and conflicting sensory situations. These variations appeared also to be related to age, sex, and weight and could be explained by fluctuant joint pain in a daytime. As feasible and recommended non-pharmacologic treatment, hydrotherapy is beneficial to the improvement of postural stability in elderly patients with knee OA, especially combining with targeted individual rehabilitation programs. These findings are important for future studies aiming at enhancing postural stability in knee OA patients and should be taken into account in the management of knee OA to generate applicative approaches to prevent the occurrence of adverse events in patient’s daily life.

The circadian cycle, although seasonally adjusted, consists of two phases: a nocturnal period of darkness and a diurnal period of light. Many parameters of human physiology display either a nocturnal or diurnal peak as seen in athletic performance, immune, endocrine, physiology and cognitive function, respectively. The studies included in this thesis focused on the diurnal (morning or AM versus evening or PM) effect of high-intensity self-paced exercise on physiological and immunological measures and the influence of individual preference for activity or chronotype on these responses. Self-paced time-trials were completed in an environmental chamber (6°C) in the AM and PM and displayed a similar effect on physiological and biological parameters. Performance times were non-statistically quicker (P > 0.05) at PM. Physiological parameters heart rate, rate of perceived exertion, lung function and self-paced treadmill speed were not found to be statistically different at AM or PM trial (p > 0.05). Core body temperature (CBT), was significantly higher (p0.05). CD8+ T-lymphocyte cell-surface markers for naïve/senescence and differentiation (CD27CD45RA and CD27CD28) reported no diurnal difference between AM and PM exercise in experienced and experienced/recreational distance runners respectively (P > 0.05). However, a higher percentage of highly differentiated phenotypes were found in the recreationally active population. Neutrophils displayed a pronounced elevation in response to PM exercise with the mechanism driving this response unclear at this time. Cortisol concentration displayed less inflammatory responses in the morning compared to the evening with higher values pre, post and one-hour post AM trials. Chronotype showed no effect on physiology or biology at rest or in response to exercise. Chapter 4 presents data from a study that investigated diurnal physiology and immune response to high-intensity exercise in highly-trained men. Recreational and experienced endurance male runners at differing diurnal time-points were investigated in Chapter 5, while individual chronotype differences and circadian phase responses were explored in Chapter 6.In summary, it is concluded from this work that there was a lack of evidence showing a diurnal effect on running performance and subsequent immune response. Elevated circulating immune counts prior to exercise, irrespective of diurnal phase, appear to govern exercise-induced responses. The effect of high intensity exercise is subject to three distinct variables: the fitness status and experience of the individual completing the exercise, the time of day at which the exercise is undertaken, and the phase response of exercise at that point of the circadian cycle. No diurnal phase mediated a divergent effect on variables examined was observed at 09.00hrs and 17.00hrs. These time-points should be considered not sufficiently dissimilar to elucidate diurnal variation in trained and healthy males.

<p>Elevated temperatures accompanying climate warming are expected to have adverse effects on sensitive lichen species. This premise was examined by measuring the sensitivity of different lichen species to elevated temperatures in the laboratory and in the field. Laboratory studies involved the exposure of nine hydrated lichen species (Xanthoparmelia austro-africana, X. hyporhytida, Xanthoparmelia sp., Xanthomaculina hottentotta, Teloschistes capensis, Ramalina sp., Flavopuntelia caperata, Lasallia papulosa, Parmotrema austrosinensis) collected from sites of different aridity and mean annual temperature for 2 hourly intervals to temperatures ranging from 24&ordm / C to 48&ordm / C in a forced daft oven and measuring their respiration rates and maximum quantum yield of PSII. Field studies involved simultaneous hourly measurements of ground surface air temperatures and Lichen effective quantum yield of PSII of hydrated lichen species populations under ambient and artificially modified environmental conditions.</p>

In recent years, the rapid development of economy and industry in Xiamen Bay causes serious environmental problems, particularly poor air quality and visibility impairment. There are no large-scale industrial emission sources in Kinmen Island, however, its ambient air quality is always the poorest in Taiwan. Moreover, ambient air quality monitoring data showed that PM10 concentrations varied in daytime and at nighttime. Consequently, this study tired to ascertain the potential causes for this phenomenon. This study selected ten particulate matter (PM) sampling sites at Xiamen Bay, including five sites at Kinmen Island and five sites at metro Xiamen. Particulate matter sampling was conducted in daytime (8:00-17:00) and at nighttime (17:00-8:00), which included regular and intensive sampling. Regular sampling was conducted to collect PM10 with high-volume samplers three times a month from April 2009 to April 2010, while intensive sampling was conducted to collect fine (PM2.5) and coarse (PM2.5-10) particles with dichotomous samplers and particle size distribution with a MOUDI at site B2 for consecutive 5 days in the spring and winter of 2009~2010. After sampling, the physicochemical properties of PM, including mass concentrations, particle size distribution, water- soluble ionic species, metallic elements, and carbonaceous contents were further analyzed. The level of atmospheric PM is affected by meteorological condition, thus PM10 concentrations in winter and fall was much higher than those in spring and summer. Results from backward trajectories showed that the concentrations of PM10 blown from the north were generally higher than those from the south. Furthermore, t-test analysis indicated that PM10 concentrations in daytime and at nighttime at site B3 were significantly different (p-value<0.05). During the intensive sampling periods, PM10 concentrations were mainly affected by coarse particles compared to fine particles. The highest concentration for fine and coarse particle modes occurred at the size ranges of 0.32~0.56 £gm and 3.2~5.6 £gm, respectively. The most abundant water-soluble ionic species of PM10 were secondary inorganic aerosols (SO42-, NO3-, and NH4+) which accounted for 85% of total ions. The daytime and nighttime PM10 concentration ratios (D/N) for Mg, K, Ca, Cr, Mn, Fe, Zn, Al, Cu, As, and V were in the same order of magnitude, however, the D/N ratios of Cd, Pb, Ni, and Ti in spring and summer varied higher than an order of magnitude, indicating that the emission sources of PM were different in daytime and at nighttime. Correlation analysis of OC and EC showed that OC and EC at nighttime had a higher correlation than those in daytime, while OC and EC had a higher correlation in Kinmen Island than those in metro Xiamen, indicating carbonaceous sources must be different in summer and winter at Xiamen Bay. Enrichment factor analysis revealed that ceramic industry, stone processing, and cement industry had higher correlation with PM10 concentration than utility power plants. Crustal dusts consisted of road dusts, farmland dusts, and constructive dusts, while biomass burning was not a negligible sources. Results obtained from PCA and CMB receptor modeling showed that major sources of PM in Xiamen Bay were secondary inorganic aerosols, fuel and biomass burning, marine aerosols, vehicular exhansts, and soil dusts. Besides, stone processing, cement industry, ceramic industry, and utility power plants had the highest contribution in winter. Their contributions in daytime and at nighttime were 38% and 45%, respectively.

Sperm whales (Physeter macrocephalus) are nomadic species typically studied across broad (>100km) spatial scales. In this study, I model fine-scale (or submesocale) habitat preferences, determine how organization into distinctive units of associating female and juveniles influences habitat use, and describe how movements change across the 24-hour cycle. This study concerns a well-studied population of sperm whales off Dominica in the Eastern Caribbean. Statistical models suggest that overall habitat use is rather homogenous, and social behaviour is best predicted by the presence of mature males. Variation among social units in the amount of time spent, and space occupied, within the study area indicates habitat preferences at the level of the social unit. Finally, movements are influenced by the diurnal cycle, as whales tend to move from inshore to offshore at dusk. This study betters our understanding of sperm whale habitat decisions over fine-scales, and has implication for conservation and management strategies.

<p>Elevated temperatures accompanying climate warming are expected to have adverse effects on sensitive lichen species. This premise was examined by measuring the sensitivity of different lichen species to elevated temperatures in the laboratory and in the field. Laboratory studies involved the exposure of nine hydrated lichen species (Xanthoparmelia austro-africana, X. hyporhytida, Xanthoparmelia sp., Xanthomaculina hottentotta, Teloschistes capensis, Ramalina sp., Flavopuntelia caperata, Lasallia papulosa, Parmotrema austrosinensis) collected from sites of different aridity and mean annual temperature for 2 hourly intervals to temperatures ranging from 24&ordm / C to 48&ordm / C in a forced daft oven and measuring their respiration rates and maximum quantum yield of PSII. Field studies involved simultaneous hourly measurements of ground surface air temperatures and Lichen effective quantum yield of PSII of hydrated lichen species populations under ambient and artificially modified environmental conditions.</p>