Flow and water budgets in the C-111 and L-31W canals near the Everglades National Park, Dade County, Florida

Acoustic velocity meter (AVM) sites, located both distant and adjacent to canal water control structures, were constructed and calibrated in L-31W borrow canal and Canal 111 (C-111) to measure canal water velocity. Data were used to compute monthly discharge volumes and overall water budgets for several canal reaches from August 1994 to May 1996. The water budgets indicated extensive aquifer inflows in L-31W associated, in part, with S-332 pump station return flows. Canal and groundwater piezometer data showed 5 distinct hydrologic scenarios (distinguished by the direction and magnitude of hydraulic gradients) in the important Frog Pond area on the eastern boundary of the Everglades National Park. Most of the water lost from C-111 was via surface water losses near the outlet of the system, close to Florida Bay. The distribution of flows during the study suggest an alteration of the present South Dade Conveyance System modification plan to improve water deliveries to Taylor Slough and the Eastern Panhandle of the Everglades National Park. ^

Assessing the net effect of anthropogenic disturbance on aquatic communities in wetlands: community structure relative to distance from canals

Anthropogenic alterations of natural hydrology are common in wetlands and often increase water permanence, converting ephemeral habitats into permanent ones. Since aquatic organisms segregate strongly along hydroperiod gradients, added water permanence caused by canals can dramatically change the structure of aquatic communities. We examined the impact of canals on the abundance and structure of wetland communities in South Florida, USA. We sampled fishes and macroinvertebrates from marsh transects originating at canals in the central and southern Everglades. Density of all aquatic organisms sampled increased in the immediate proximity of canals, but was accompanied by few compositional changes based on analysis of relative abundance. Large fish (>8 cm), small fish (<8 >cm) and macroinvertebrates (>5 mm) increased in density within 5 m of canals. This pattern was most pronounced in the dry season, suggesting that canals may serve as dry-down refugia. Increases in aquatic animal density closely matched gradients of phosphorus enrichment that decreased with distance from canals. Thus, the most apparent impact of canals on adjacent marsh communities was as conduits for nutrients that stimulated local productivity; any impact of their role as sources of increased sources of predators was not apparent. The effect of predation close to canals was overcompensated by increased secondary productivity and/or immigration toward areas adjacent to canals in the dry season. Alternatively, the consumptive effect of predatory fishes using canals as dry-season refuges is very small or spread over the expanse of marshes with open access to canals.

Canals as Vectors for Fish Movement: Potential Southward Range Expansion of Lepisosteus osseus L. (Longnose Gar) in South Florida

Lepisosteus osseus (Longnose Gar) is a large-bodied predator, whose Florida distribution remains unclear at the southern edge of its range. We reviewed available literature and museum voucher specimens to provide a more accurate range description, and we discuss recent collections in south Florida. Longnose Gar has not been previously reported in natural habitats south of Lake Okeechobee. Instead, records south of the lake are from canals, and most are recent (since 2000), including our own southernmost 2011 record. No records from Everglades natural habitats have been collected. Previous studies have shown native range expansions in anthropogenically disturbed landscapes. We suggest that the Longnose Gar is expanding its range southward in Florida using canals as dispersal vectors and/or suitable habitat.

Map of New Jersey and Pennsylvania exhibiting the post offices, post roads, canals, rail roads, &c.

Scale ca. 1:650,000.

Incidence and classification of bifid mandibular canals using cone beam computed tomography

Aim: To determine the prevalence and classification of bifid mandibular canals using cone beam computed tomography (CBCT). Methods: The sample comprised 300 CBCT scans obtained from the Radiology and Imaging Department database at São Leopoldo Mandic Dental School, Campinas, SP, Brazil. All images were performed on Classic I-Cat® CBCT scanner, with standardized voxel at 0.25 mm and 13 cm FOV (field of view). From an axial slice (0.25 mm) a guiding plane was drawn along the alveolar ridge in order to obtain a cross-section. Results: Among 300 patients, 188 (62.7%) were female and 112 (37.3%) were male, aged between 13 to 87 years. Changes in the mandibular canal were observed in 90 patients, 30.0% of the sample, 51 women (56.7%) and 39 men (43.3%). Regarding affected sides, 32.2% were on the right and 24.5% on the left, with 43.3% bilateral cases. Conclusions: According to the results obtained in this study, a prevalence of 30% of bifid mandibular canals was found, with the most prevalent types classified as B (mesial direction) and bilateral.

Spatial and Temporal Patterns in the Distribution, Behavior, and Activity of Fishes in Canals of the Everglades

Landscape characteristics, disturbances, and temporal variability influence predator-prey relationships, but are often overlooked in experimental studies. In the Everglades, seasonal disturbances force the spatial overlap of predators and prey, potentially increasing predation risk for prey. This study examined seasonal and diel patterns of fish use of canals and assessed predation risk for small fishes using an encounter rate model. I deployed an imaging sonar in Everglades canals to quantify density and swimming speeds of fishes, and detect anti-predator behaviors by small fishes. Generally, seasonal declines of marsh water-levels increased the density of large fishes in canals. Densities of small and large fishes were positively correlated and, as small-fish density increased, schooling frequency also increased. At night, schools disbanded and small fishes were observed congregating along the canal edge. The encounter rate model predicted highest predator-prey encounters during the day, but access to cover may reduce predation risk for small fishes.

Effect of sonic and ultrasonic activation on organic tissue dissolution from simulated grooves in root canals using sodium hypochlorite and EDTA

Aim: To compare soft-tissue dissolution by sodium hypochlorite, with an EDTA intermediate rinse, with or without activation with passive ultrasonic activation (PUI) or sonic activation using the Endoactivator (EA) or Eddy tips (ED). Methodology: The root canals of eighty-three human maxillary central incisors were chemo-mechanically prepared and the teeth split. A standardized longitudinal intracanal groove was created in one of the root halves. Eighty-three porcine palatal mucosa samples were collected, adapted to fit into the grooves and weighed. The re-assembled specimens were randomly divided into four experimental groups (n = 20), based on the final rinse: no activation; EA; PUI; ED, using 2.5% sodium hypochlorite, with an EDTA intermediate rinse. A control group (n = 3) was irrigated with distilled water without activation. The solutions were delivered using a syringe and needle 2 mm from working length. Total irrigation time was 150 s, including 60 s of activation in the specific groups. The study was carried out at 36 ± 2 °C. The porcine palatal mucosa samples were weighed after completion of the assays. Student paired t-test and anova were used to assess the intra- and intergroup weight changes. The multiple comparisons were evaluated using Bonferroni correction (α = 0.05). Results: Weight loss occurred in all experimental groups. Irrigant activation resulted in greater weight loss when compared to the nonactivated group [vs. EA (P = 0.001); vs. PUI (P < 0.001); vs. ED (P < 0.001)]. No significant differences were found amongst the different activation systems. Conclusions: Activation increased the tissue-dissolving activity of irrigants from artificial grooves in root canals of maxillary central incisors. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

Water Delivery Quality and Automatic Control Modes in Irrigation Canals. A Case Study.

Regarding canal management modernization, water savings and water delivery quality, the study presents two automatic canal control approaches of the PI (Proportional and Integral) type: the distant and the local downstream control modes. The two PI controllers are defined, tuned and tested using an hydraulic unsteady flow simulation model, particularly suitable for canal control studies. The PI control parameters are tuned using optimization tools. The simulations are done for a Portuguese prototype canal and the PI controllers are analyzed and compared considering a demand-oriented-canal operation. The paper presents and analyzes the two control modes answers for five different offtake types – gate controlled weir, gate controlled orifice, weir with or without adjustable height and automatic flow adjustable offtake. The simulation results are compared using water volumes performance indicators (considering the demanded, supplied and the effectives water volumes) and a time indicator, defined taking into account the time during which the demand discharges are effective discharges. Regarding water savings, the simulation results for the five offtake types prove that the local downstream control gives the best results (no water operational losses) and that the distant downstream control presents worse results in connection with the automatic flow adjustable offtakes. Considering the water volumes and time performance indicators, the best results are obtained for the automatic flow adjustable offtakes and the worse for the gate controlled orifices, followed by the weir with adjustable height.

Irrigation and drainage canals role for plant diversity and nature conservation

Aims: With this research, we wanted to investigate and promote the conservation of biodiversity in the network of drainage canals of the Po Valley Study area: The canal network of Bologna plain, long more than 1150 km (Po Valley, North Italy) Methods: In Chapter II we analyzed the geographical patterns that characterize our transects, the land use of their upstream basins, the water quality at the closure points of their river basins. In Chapter III we described the plant communities with some ecological information and we also tested the effect of the canal size on the plant communities. In Chapter IV we described the relation beetween some functional traits of the plant species sampled and some environmental parameters Results: A total of 272 species were sampled in 118 transects. The plant communities of the drainage canals have been found to have a significant influence: the geographical pattern "proximity to protected areas", the class of land use "agrozootechnical settlements", and some water parameters. The analysis of the parameter "canal depth" indicated a significant distinction between small and large canals based on plant communities. The functional composition of the plant communities was affected by the bank aspect, the inclusion/exclusion from the protected areas and the upstream basin land uses. Moreover, the functional groups of species responded differently to environmental drivers, water quality gradients and were influenced by a combination of environmental stresses Conclusions: This research confirms the key role of the canals network in sustaining the plant richness in oversimplified landscapes. Considering the fragility of the floodplains and the global warming that is taking place, it is necessary to rethink the role of irrigation canals and their plant communities in the near future. This work reinforces the belief that long-term sampling plans and greater knowledge about canal management practices are needed

Heavy Metals distribution in drainage canals sediments of the Ravenna province

This work, in collaboration with the Romagna Reclamation Consortium, has the aim of studying the heavy metals concentration distribution in the drainage canals of the Ravenna coastal basins, Italy. Particular attention was given to the area of the V Fosso Ghiaia and VI Bevanella basins, where water and sediment samples were collected in the field and integrated with existing databases. The hydrological regime is controlled and managed by the Consortium, which has divided the territory into several mechanical drainage basins. XRF was performed on 21 sediment samples and pH, EC, T°, Fe2+ and Fetot were measured on 15 water samples by probes and spectrophotometer, respectively. Heavy metals concentrations exceeding legal limits of the D.LGS n ° 152/2006 were found for As, Co, Cr, Pb and Zn. These results were then integrated with canal sediment analyses provided by the Consortium to perform a Principal Component Analysis. PCA results show that the main variable affecting heavy metals distribution is the use of fertilizers, followed by distance from sea, and altimetry, which are directly linked to salinity. Heavy metals concentrations increase with increasing use of fertilizers, which are mainly due to the widespread agricultural practices and industrial land use in the area. High heavy metals concentrations are also found in the canals interested by higher salinity (especially Pinetale Ramazzotti). In fact, the area is affected by salinization caused by a water table below sea level and upward seepage of salty oxygen-poor saline water from the bottom of the aquifer. According to the literature, iron and manganese oxides were found to be an important factor in controlling the heavy metals distribution.

Microbial Evaluation Of Traumatized Teeth Treated With Triple Antibiotic Paste Or Calcium Hydroxide With 2% Chlorhexidine Gel In Pulp Revascularization.

Revascularization outcome depends on microbial elimination because apical repair will not happen in the presence of infected tissues. This study evaluated the microbial composition of traumatized immature teeth and assessed their reduction during different stages of the revascularization procedures performed with 2 intracanal medicaments. Fifteen patients (7-17 years old) with immature teeth were submitted to the revascularization procedures; they were divided into 2 groups according to the intracanal medicament used: TAP group (n = 7), medicated with a triple antibiotic paste, and CHP group (n = 8), dressed with calcium hydroxide + 2% chlorhexidine gel. Samples were taken before any treatment (S1), after irrigation with 6% NaOCl (S2), after irrigation with 2% chlorhexidine (S3), after intracanal dressing (S4), and after 17% EDTA irrigation (S5). Cultivable bacteria recovered from the 5 stages were counted and identified by means of polymerase chain reaction assay (16S rRNA). Both groups had colony-forming unit counts significantly reduced after S2 (P < .05); however, no significant difference was found between the irrigants (S2 and S3, P = .99). No difference in bacteria counts was found between the intracanal medicaments used (P = .95). The most prevalent bacteria detected were Actinomyces naeslundii (66.67%), followed by Porphyromonas endodontalis, Parvimonas micra, and Fusobacterium nucleatum, which were detected in 33.34% of the root canals. An average of 2.13 species per canal was found, and no statistical correlation was observed between bacterial species and clinical/radiographic features. The microbial profile of infected immature teeth is similar to that of primarily infected permanent teeth. The greatest bacterial reduction was promoted by the irrigation solutions. The revascularization protocols that used the tested intracanal medicaments were efficient in reducing viable bacteria in necrotic immature teeth.

Does The Reciproc File Remove Root Canal Bacteria And Endotoxins As Effectively As Multifile Rotary Systems?

To evaluate the effectiveness of Reciproc for the removal of cultivable bacteria and endotoxins from root canals in comparison with multifile rotary systems. The root canals of forty human single-rooted mandibular pre-molars were contaminated with an Escherichia coli suspension for 21 days and randomly assigned to four groups according to the instrumentation system: GI - Reciproc (VDW); GII - Mtwo (VDW); GIII - ProTaper Universal (Dentsply Maillefer); and GIV -FKG Race(™) (FKG Dentaire) (n = 10 per group). Bacterial and endotoxin samples were taken with a sterile/apyrogenic paper point before (s1) and after instrumentation (s2). Culture techniques determined the colony-forming units (CFU) and the Limulus Amebocyte Lysate assay was used for endotoxin quantification. Results were submitted to paired t-test and anova. At s1, bacteria and endotoxins were recovered in 100% of the root canals investigated (40/40). After instrumentation, all systems were associated with a highly significant reduction of the bacterial load and endotoxin levels, respectively: GI - Reciproc (99.34% and 91.69%); GII - Mtwo (99.86% and 83.11%); GIII - ProTaper (99.93% and 78.56%) and GIV - FKG Race(™) (99.99% and 82.52%) (P < 0.001). No statistical difference were found amongst the instrumentation systems regarding bacteria and endotoxin removal (P > 0.01). The reciprocating single file, Reciproc, was as effective as the multifile rotary systems for the removal of bacteria and endotoxins from root canals.

Macrophage Cell Activation With Acute Apical Abscess Contents Determined By Interleukin-1 Beta And Tumor Necrosis Factor Alpha Production.

This clinical study has investigated the antigenic activity of bacterial contents from exudates of acute apical abscesses (AAAs) and their paired root canal contents regarding the stimulation capacity by levels of interleukin (IL)-1 beta and tumor necrosis factor alpha (TNF-α) throughout the root canal treatment against macrophage cells. Paired samples of infected root canals and exudates of AAAs were collected from 10 subjects. Endodontic contents were sampled before (root canal sample [RCS] 1) and after chemomechanical preparation (RCS2) and after 30 days of intracanal medication with calcium hydroxide + chlorhexidine gel (Ca[OH]2 + CHX gel) (RCS3). Polymerase chain reaction (16S rDNA) was used for detection of the target bacteria, whereas limulus amebocyte lysate was used to measure endotoxin levels. Raw 264.7 macrophages were stimulated with AAA exudates from endodontic contents sampled in different moments of root canal treatment. Enzyme-linked immunosorbent assays were used to measure the levels of TNF-α and IL-1 beta. Parvimonas micra, Porphyromonas endodontalis, Dialister pneumosintes, and Prevotella nigrescens were the most frequently detected species. Higher levels of endotoxins were found in samples from periapical exudates at RCS1 (P < .005). In fact, samples collected from periapical exudates showed a higher stimulation capacity at RCS1 (P < .05). A positive correlation was found between endotoxins from exudates with IL-1 beta (r = 0.97) and TNF-α (r = 0.88) production (P < .01). The significant reduction of endotoxins and bacterial species achieved by chemomechanical procedures (RCS2) resulted in a lower capacity of root canal contents to stimulate the cells compared with that at RCS1 (P < .05). The use of Ca(OH)2 + CHX gel as an intracanal medication (RCS3) improved the removal of endotoxins and bacteria from infected root canals (P < .05) whose contents induced a lower stimulation capacity against macrophages cells at RCS1, RCS2, and RCS3 (P < .05). AAA exudates showed higher levels of endotoxins and showed a greater capacity of macrophage stimulation than the paired root canal samples. Moreover, the use of intracanal medication improved the removal of bacteria and endotoxins from infected root canals, which may have resulted in the reduction of the inflammatory potential of the root canal content.

Root Canal Content From Primary Endodontic Infection And Upregulation Of Gelatinases In Fibroblast Cells.

To investigate endotoxin levels from primary endodontic infections before and after chemomechanical preparation (CMP) and to determine their antigenicity against 3T3 fibroblasts through gelatinolytic activity of matrix metalloproteinases (MMPs). Twenty-four root canals with primary endodontic infection and apical periodontitis were selected. Samples were collected using paper points before (S1) and after chemomechanical preparation (CMP) (S2). The limulus amebocyte lysate assay was used for endotoxin measurement. Fibroblasts were stimulated with root canal contents for 24 h. Supernatants of cell cultures stimulated with root canal contents were collected after 24 h to determine the levels of MMP-2 and MMP-9 gelatinolytic activity using the zymography technique. Friedman and Wilcoxon tests were used to compare the amount of endotoxin before (S1) and after CMP (S2) (P < 0.05). Data obtained from gelatinolytic activity were analysed using anova and Tukey's tests (P < 0.05). Endotoxin was recovered in 100% of the samples. There was a significant reduction in endotoxin levels after CMP (P < 0.05). A correlation was found between the levels of endotoxins and MMP-2 expression (P < 0.05). Root canal contents of initial samples (S1) induced significantly greater MMP-2 expression by fibroblasts when compared to S2 and the nonstimulated group (P < 0.05). No gelatinolytic activity of MMP-9 was observed in S1, S2 and control group. Root canal contents from primary endodontic infections had gelatinolytic activity for MMP-2. Moreover, CMP was effective in reducing endotoxin levels and their antigenicity against fibroblasts on gelatinolytic activity.