Identifying representative watershed for the Urmia Lake Basin, Iran.

Designation of representative watersheds (RWs) as a reference area representing key behavior of the whole region is an essential tool to provide a time and cost-effective basis for monitoring watershed performance against different driving forces. It is more important in developing countries facing lack of necessary investments in one hand and ever-increasing human interventions and need to assess the outcome behavior of the system in another hand. However, this serious affair has been less considered worldwide, in general, and in developing countries, in particular. Therefore, in the present study, a quantitative-based method of Representative Watershed Index (RWI) with potential range from 0 to 100 has been formulated using four important criteria and available national-wide raster data of elevation (meter), slope (%), rainfall erosivity factor (t m ha-1 cm h-1), and land use. The approach was then applied to the data prepared for the unique and invaluable global water ecosystem of the Urmia Lake Basin (ULB), north-western Iran, as a case study. The input raster was overlaid via matrices programming in the MATrix LABoratory (MATLAB) 2016 and Geographic Information System (GIS) 9.3 software environments. The RWIs were accordingly computed for 61 sub-watersheds of the ULB. The RWIs resulted from quadri-partite dimensional matrices that varied from 5.54 to 53.46 with respective maximum dissimilarity and resemblance with the entire 61 study sub-watersheds in the region. However, the sub-watershed with RWI of 40.65 (No. 57) was proposed as the final RW for the whole ULB due to hydrological independency, appropriate locality, and existence of functioning meteorological and hydrometric stations. The identified RW would be suggested to be considered as the basis for future insight monitoring and assessing environmental issues for the region eventually leading to an appropriate adaptive watershed management. Graphical abstract ᅟ.

Sediment Source Fingerprinting of the Lake Urmia Sand Dunes.

Aeolian sand dunes are continuously being discovered in inner dry lands and coastal areas, most of which have been formed over the Last Glacial Maximum. Presently, due to some natural and anthropogenic implications on earth, newly-born sand dunes are quickly emerging. Lake Urmia, the world's second largest permanent hypersaline lake, has started shrinking, vast lands comprising sand dunes over the western shore of the lake have appeared and one question has been playing on the minds of nearby dwellers: where are these sand dunes coming from, What there was not 15 years ago!! In the present study, the determination of the source of the Lake Urmia sand dunes in terms of the quantifying relative contribution of each upstream geomorphological/lithological unit has been performed using geochemical fingerprinting techniques. The findings demonstrate that the alluvial and the fluvial sediments of the western upstream catchment have been transported by water erosion and they accumulated in the lower reaches of the Kahriz River. Wind erosion, as a secondary agent, have carried the aeolian sand-sized sediments to the sand dune area. Hence, the Lake Urmia sand dunes have been originating from simultaneous and joint actions of alluvial, fluvial and aeolian processes.

Is Low-Level Laser Therapy Effective for Treatment of Neurosensory Deficits Arising From Sagittal Split Ramus Osteotomy?

PURPOSE: This study investigated the effectiveness of low-level laser therapy (LLLT) for treating neurosensory impairment after bilateral sagittal split osteotomy (BSSO). MATERIALS AND METHODS: This randomized, double-blinded, split-mouth trial included patients requiring BSSO. After surgery, 1 side of each patient was randomly assigned to laser therapy and the other side served as the control. At 24, 48, and 72 hours after surgery, LLLT was accomplished by intraoral application of a 660-nm laser around the surgical site (200 mW, 10 seconds, 2 J, 1.5 J/cm2) followed by extraoral irradiation by an 810-nm laser (200 mW, 10 seconds, 2 J, 7 J/cm2) along the distribution of the inferior alveolar nerve. Subsequently, extraoral irradiation was repeated 2 times per week for 3 weeks along the path of the inferior alveolar nerve, lower lip, and chin. On the control side, the treatment was similar to the laser side but with laser simulation. The main outcome was assessing nerve damage by a "2-point discrimination test" before and up to 60 days after surgery. RESULTS: The sample consisted of 16 patients. No significant difference was found between the laser and control sides before and after surgery and on postoperative days 15 and 30 (P > .05). The 2-point discrimination distance was significantly shorter on the laser side than on the control side on postoperative days 45 and 60 (P < .05). CONCLUSION: LLLT was effective in the treatment of neurosensory disturbances arising from BSSO. Therefore, LLLT can be recommended to accelerate the recovery of sensory aberrations in patients undergoing BSSO.

Comparison of air-driven vs electric torque control motors on canal centering ability by ProTaper NiTi rotary instruments.

AIM: Cleaning and shaping is one of the most important phases in root canal therapy. Various rotary NiTi systems minimize accidents and facilitate the shaping process. Todays NiTi files are used with air-driven and electric handpieces. This study compared the canal centering after instrumentation using the ProTaper system using Endo IT, electric torque-control motor, and NSK air-driven handpiece. MATERIALS AND METHODS: This ex vivo randomized controlled trial study involved 26 mesial mandibular root canals with 10 to 35° curvature. The roots were randomly divided into 2 groups of 13 canals each. The roots were mounted in an endodontic cube with acrylic resin, sectioned horizontally at 2, 6 and 10 mm from the apex and then reassembled. The canals were instrumented according to the manufacturer's instructions using ProTaper rotary files and electric torque-control motors (group 1) or air-driven handpieces (group 2). Photographs of the cross-sections included shots before and after instrumentation, and image analysis was performed using Photoshop software. The centering ability and canal transportation was also evaluated. Repeated measurement and independent t-test provided statistical analysis of canal transportation. RESULTS: The comparison of the rate of transportation toward internal or external walls between the two groups was not statistically significant (p = 0.62). Comparison of the rate of transportation of sections within one group was not significant (p = 0.28). CONCLUSION: Use of rotary NiTi file with either electric torquecontrol motor or air-driven handpiece had no effect on canal centering. CLINICAL SIGNIFICANCE: NiTi rotary instruments can be used with air-driven motors without any considerable changes in root canal anatomy, however it needs the clinician to be expert.