Improvement of the Piezoresistive Behavior of Poly (vinylidene fluoride)/Carbon Nanotube Composites by the Addition of Inorganic Semiconductor Nanoparticles.

Conductive polymer composites (CPCs), obtained by incorporating conductive fillers into a polymer matrix, are suitable for producing strain sensors for structural health monitoring (SHM) in infrastructure. Here, the effect of the addition of inorganic semiconductor nanoparticles (INPs) to a poly (vinylidene fluoride) (PVDF) composite filled with multi-walled carbon nanotubes (MWCNTs) on the piezoresistive behavior is investigated. INPs with different morphologies and sizes are synthesized by a hydrothermal method. The added inorganic oxide semiconductors showed two distinct morphologies, including different phases. While particles with flower-like plate morphology contain phases of orth-ZnSnO3 and SnO, the cauliflower-like nanoparticles contain these metal oxides and ZnO. The nanoparticles are characterized by field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD), and the nanocomposites by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). Cyclic tensile testing is applied to determine the strain-sensing behavior of PVDF/1 wt% MWCNT nanocomposites with 0-10 wt% inorganic nanoparticles. Compared to the PVDF/1 wt% MWCNT nanocomposite, the piezoresistive sensitivity is higher after the addition of both types of nanoparticles and increases with their amount. Thereby, nanoparticles with flower-like plate structures improve strain sensing behavior slightly more than nanoparticles with cauliflower-like structures. The thermogravimetric analysis results showed that the morphology of the semiconductor nanoparticles added to the PVDF/MWCNT matrix influences the changes in thermal properties.

Development of a site selection methodology for run-of-river hydroelectric power plants within the water-energy-ecosystem nexus.

Even though water-energy systems and ecosystems have complex relationships, regional energy policies seldom consider this connection. The current regional energy policies are developed primarily based on technical and socio-economical aspects and lack ecological considerations that may deteriorate the ecosystems and sustainability of these policies. Hence, considering the water-energy-ecosystem nexus in the development stage of the energy policies can aid decision-makers in initiating successful multi-dimensional energy policies. This study proposes a novel approach to develop an environmental index to support the regional energy policies that rely on Run-of-river (RoR) hydroelectric power plants (HEPPs) with a nexus approach. First, significant environmental impacts of RoR HEPPs are identified as environmental flows, impacts on ecologically valuable areas such as heritage sites, wetlands, national parks, river water quality degradation, modification of habitat, and impact on ecosystems and biodiversity loss. Then these impacts are represented through indicators and are aggregated into an overall environmental performance index through a fuzzy multi-criteria decision-making approach. The proposed approach allows the integration of ecological dimensions into the evaluation of RoR HEPPs through easy-to-measure indicators, among which environmental flow is a critical component.

Ultrasonography and erythrocyte distribution width in patients with plantar fasciitis.

BACKGROUND: The measurement of plantar fascia thickness with ultrasonography can be used for both for diagnosis and as a response-to-treatment parameter in plantar fasciitis. Furthermore, with the recent studies, red cell distribution width may be used as an inflammatory marker. Aim of this study is to investigate the association of red cell distribution width and ultrasonography on diagnosis and monitoring of treatment in patients with plantar fasciitis. METHODS: Clinically diagnosed 102 patients with plantar fasciitis between the dates January 2016 to July 2018 were analysed. Hemogram, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and plantar fascial ultrasonography were obtained on initial evaluation and in 1 month, 2 months and 3 months of the standard nonoperative treatment; American Orthopaedic Foot & Ankle Hindfoot Score (AOFAS) and Visual Analog Scale (VAS) scores were recorded. Posthoc and multivariate logistic regression analysis were used for statistical analysis on SPSS 21.0. RESULTS: Red cell distribution width was correlated with plantar fascia thickness by the end of the 1 month (r=0.26, P=.013). Female sex, BMI over 30kg/m2, higher red cell distribution width and higher plantar fascia thickness were associated with plantar fasciitis on initial evaluation. Higher red cell distribution width together with higher plantar fascia thickness were also found to be a risk factor for both on initial evaluation and 1 month after treatment in plantar fasciitis. CONCLUSION: This study shows that association of red cell distribution width and plantar fascia thickness can be not only a diagnostic predictor but also an indicator of treatment response in plantar fasciitis. LEVEL OF CLINICAL EVIDENCE: Level IV.

Intravoxel incoherent motion parameters in the evaluation of chronic hepatitis B virus-induced hepatic injury: fibrosis and capillarity changes.

OBJECTIVE: To evaluate the diagnostic efficacy of intravoxel incoherent motion (IVIM) parameters in hepatitis B virus (HBV)-induced hepatic fibrosis using different calculation methods and to investigate histopathologic origins. MATERIALS AND METHODS: Liver biopsies from 37 prospectively recruited chronic hepatitis B patients were obtained. Twelve b-value (0-1000 s/mm2) diffusion-weighted imaging (DWI) was performed with a 1.5 T scanner and was followed by blinded percutaneous liver biopsy. All biopsy specimens were evaluated with Ishak staging, and the microvascular density (MVD) was calculated. Patients were classified as having no/mild (F0-1), moderate (F2-3), or marked (F4-5) fibrosis. Pseudodiffusion (D*), the perfusion fraction (f), and the apparent diffusion coefficient (ADC) were calculated using all b-values, while true diffusion (D) was calculated using all b-values [D0-1000] and b-values greater than 200 s/mm2 [D200-1000]. Three concentric regions of interest (ROIs) (5, 10, and 20 mm) centered on the biopsy site were used. RESULTS: D* was correlated with the MVD (p = 0.015, Pearson's r = 0.415), but f was not (p = 0.119). D0-1000 was inversely correlated with Ishak stage (p = 0.000, Spearman's rs = - 0.685) and was significantly decreased in all the fibrosis groups; however, only the no/mild and marked fibrosis groups had significantly different D200-1000 values. A pairwise comparison of receiver operating characteristic (ROC) curves of D0-1000 and D200-1000 showed significant differences (p = 0.039). D* was the best at discriminating early fibrosis (AUC = 0.861), while the ADC best discriminated advanced fibrosis (AUC = 0.964). CONCLUSION: D* was correlated with the MVD and is a powerful parameter to discriminate early hepatic fibrosis. D significantly decreased with advanced fibrosis stage when using b-values less than 200 s/mm2 in calculations.

Predicting clinical outcomes in neuroblastoma with genomic data integration.

BACKGROUND: Neuroblastoma is a heterogeneous disease with diverse clinical outcomes. Current risk group models require improvement as patients within the same risk group can still show variable prognosis. Recently collected genome-wide datasets provide opportunities to infer neuroblastoma subtypes in a more unified way. Within this context, data integration is critical as different molecular characteristics can contain complementary signals. To this end, we utilized the genomic datasets available for the SEQC cohort patients to develop supervised and unsupervised models that can predict disease prognosis. RESULTS: Our supervised model trained on the SEQC cohort can accurately predict overall survival and event-free survival profiles of patients in two independent cohorts. We also performed extensive experiments to assess the prediction accuracy of high risk patients and patients without MYCN amplification. Our results from this part suggest that clinical endpoints can be predicted accurately across multiple cohorts. To explore the data in an unsupervised manner, we used an integrative clustering strategy named multi-view kernel k-means (MVKKM) that can effectively integrate multiple high-dimensional datasets with varying weights. We observed that integrating different gene expression datasets results in a better patient stratification compared to using these datasets individually. Also, our identified subgroups provide a better Cox regression model fit compared to the existing risk group definitions. CONCLUSION: Altogether, our results indicate that integration of multiple genomic characterizations enables the discovery of subtypes that improve over existing definitions of risk groups. Effective prediction of survival times will have a direct impact on choosing the right therapies for patients. REVIEWERS: This article was reviewed by Susmita Datta, Wenzhong Xiao and Ziv Shkedy.

A pollution fate and transport model application in a semi-arid region: Is some number better than no number?

Fate and transport models are powerful tools that aid authorities in making unbiased decisions for developing sustainable management strategies. Application of pollution fate and transport models in semi-arid regions has been challenging because of unique hydrological characteristics and limited data availability. Significant temporal and spatial variability in rainfall events, complex interactions between soil, vegetation and topography, and limited water quality and hydrological data due to insufficient monitoring network make it a difficult task to develop reliable models in semi-arid regions. The performances of these models govern the final use of the outcomes such as policy implementation, screening, economical analysis, etc. In this study, a deterministic distributed fate and transport model, SWAT, is applied in Lake Mogan Watershed, a semi-arid region dominated by dry agricultural practices, to estimate nutrient loads and to develop the water budget of the watershed. To minimize the discrepancy due to limited availability of historical water quality data extensive efforts were placed in collecting site-specific data for model inputs such as soil properties, agricultural practice information and land use. Moreover, calibration parameter ranges suggested in the literature are utilized during calibration in order to obtain more realistic representation of Lake Mogan Watershed in the model. Model performance is evaluated using comparisons of the measured data with 95%CI for the simulated data and comparison of unit pollution load estimations with those provided in the literature for similar catchments, in addition to commonly used evaluation criteria such as Nash-Sutcliffe simulation efficiency, coefficient of determination and percent bias. These evaluations demonstrated that even though the model prediction power is not high according to the commonly used model performance criteria, the calibrated model may provide useful information in the comparison of the effects of different management practices on diffuse pollution and water quality in Lake Mogan Watershed.

Planning for the closure of uncontrolled landfills in Turkey to reduce environmental impacts.

Landfilling is the most preferred solid waste disposal method in Turkey owing to both economic and technical reasons. However, beside the sanitary landfills there are also hundreds of uncontrolled waste sites located throughout Turkey, which are often left either abandoned or burning. Because there is a lack of legislative guidelines governing the closure and rehabilitation of these dumpsites, the municipalities that are responsible for waste management do not initiate the proactive strategies required for the closure of these sites. In this study, a method based on a multi-criteria analysis is conducted for different dumpsites in Turkey to evaluate the level of negative impacts on the environment. This method is based on the use of environmental indices for a quantitative assessment of the landfills, such as environmental interaction between the source and the receptors, environmental values of the receptors, and operational conditions. It was possible to assess the robustness of the proposed methodology since the pre- and post-groundwater quality monitoring data was available from the study sites that were closed and rehabilitated in 2014. The results of this study show that the method based on a multi-criteria analysis is an effective tool while in the preliminary planning stages of closure and rehabilitation activities of uncontrolled waste landfills.

Diode-pumped continuous-wave and femtosecond Cr:LiCAF lasers with high average power in the near infrared, visible and near ultraviolet.

We demonstrate continuous-wave (cw), cw frequency-doubled, cw mode-locked and Q-switched mode-locked operation of multimode diode-pumped Cr:LiCAF lasers with record average powers. Up to 2.54 W of cw output is obtained around 805 nm at an absorbed pump power of 5.5 W. Using intracavity frequency doubling with a BBO crystal, 0.9 W are generated around 402 nm, corresponding to an optical-to-optical conversion efficiency of 12%. With an intracavity birefringent tuning plate, the fundamental and frequency-doubled laser output is tuned continuously in a broad wavelength range from 745 nm to 885 nm and from 375 to 440 nm, respectively. A saturable Bragg reflector is used to initiate and sustain mode locking. In the cw mode-locked regime, the Cr:LiCAF laser produces 105-fs long pulses near 810 nm with an average power of 0.75 W. The repetition rate is 96.4 MHz, resulting in pulse energies of 7.7 nJ and peak powers of 65 kW. In Q-switched mode-locked operation, pulses with energies above 150 nJ are generated.

Use of theoretical waste inventories in planning and monitoring of hazardous waste management systems.

Hazardous waste (HW) generation information is an absolute necessity for ensuring the proper planning, implementation, and monitoring of any waste management system. Unfortunately, environmental agencies in developing countries face difficulties in gathering data directly from the creators of such wastes. It is possible, however, to construct theoretical HW inventories using the waste generation factors (WGFs). The objective of this study was to develop a complete nationwide HW inventory of Turkey that relies on nation-specific WGFs to support management activities of the Turkish Ministry of Environment and Urbanization (MoEU). Inventory studies relied on WGFs from: (a) the literature and (b) field studies and analysis of waste declarations reflecting country-specific industrial practices. Moreover, new tools were introduced to the monitoring infrastructure of MoEU to obtain a comprehensive waste generation data set. Through field studies and a consideration of country specific conditions, it was possible to more thoroughly elucidate HW generation trends in Turkey, a method that was deemed superior to other alternatives. Declaration and literature based WGFs also proved most helpful in supplementing field observations that could not always be conducted. It was determined that these theoretical inventories could become valuable assets in supporting regulating agencies in developing countries for a more thorough implementation of HW management systems.

Modeling evaluation of integrated strategies to meet proposed dissolved oxygen standards for the Chicago waterway system.

The Chicago Waterway System (CWS) is a 113.8 km branching network of navigable waterways controlled by hydraulic structures in which the majority of flow is treated sewage effluent and there are periods of substantial combined sewer overflow. The Illinois Pollution Control Board (IPCB) designated the majority of the CWS as Secondary Contact and Indigenous Aquatic Life Use waters in the 1970s and made small alterations to these designations in 1988. Between 1988 and 2002 substantial improvements in the pollution control and water-quality management facilities were made in the Chicago area. The results of a Use Attainability Analysis led the Illinois Environmental Protection Agency (IEPA) to propose the division of the CWS into two new aquatic life use classes with appropriate dissolved oxygen (DO) standards. To aid the IPCB in their deliberations regarding the appropriate water use classifications and DO standards for the CWS, the DUFLOW model that is capable of simulating hydraulics and water-quality processes under unsteady-flow conditions was used to evaluate integrated strategies of water-quality improvement facilities that could meet the proposed DO standards during representative wet (2001) and dry (2003) years. A total of 28 new supplementary aeration stations with a maximum DO load of 80 or 100 g/s and aerated flow transfers at three locations in the CWS would be needed to achieve the IEPA proposed DO standards 100% of the time for both years. A much simpler and less costly (≈one tenth of the cost) system of facilities would be needed to meet the IEPA proposed DO standards 90% of the time. In theory, the combinations of flow augmentation and new supplemental aeration stations can achieve 100% compliance with the IEPA proposed DO standards, however, 100% compliance will be hard to achieve in practice because of-(1) difficulties in determining when to turn on the aeration stations and (2) localized heavy loads of pollutants during storms that may yield violations of the DO standards even with an extensive network of supplemental aeration stations. Thus, because absolute DO standards that must be met 100% of the time will be difficult, if not impossible to comply with, DO standards that include a Wet Weather Limited Use (WWLU) designation based on rainfall amount triggering CSO events and a maximum duration that the WWLU could be applied should be considered to obtain a healthy ecosystem by applying water-quality improvement features that can be practically operated and maintained. Such a WWLU approach also was evaluated in this paper.

Valuation of environmental improvements in a specially protected marine area: a choice experiment approach in Göcek Bay, Turkey.

Although the Göcek Bay area was declared as a specially protected area by General Directorate of Natural Assets Protection, the region is threatened because of pollution resulting from increased boat tourism and lack of efficient policies. Extensive measures are being planned in order to protect the region. Coastal management requires the use of technical, social political and economic tools to create a comprehensive management strategy. For environmental investments, it is necessary that benefits and the costs of environmental improvements should be identified in monetary terms in order to determine the feasibility of the investments. The aim of this study is to determine the benefits of the management alternatives to improve environmental quality in Göcek Bay to aid decision makers. In this study, the environmental benefits that can be obtained with improved water quality and restored marine ecosystem were calculated using the Choice Experiment Method, a non-market valuation technique. Data were analyzed using Multinomial Logit Model and the results showed that, local residents and tourists are willing to pay 18TL/month and 16.6TL/tour, respectively for improvements in water quality. For improvements in marine life, local residents are willing to pay 14.8TL/month and tourists are willing to pay 11.2TL/tour. With this study, it has been seen that the results obtained will pave the way for new policies and measures against the deterioration of the marine environment of Göcek Bay.

Allocation of supplementary aeration stations in the Chicago waterway system for dissolved oxygen improvement.

The Chicago Waterway System (CWS), used mainly for commercial and recreational navigation and for urban drainage, is a 122.8 km branching network of navigable waterways controlled by hydraulic structures. The CWS receives pollutant loads from 3 of the largest wastewater treatment plants in the world, nearly 240 gravity Combined Sewer Overflows (CSO), 3 CSO pumping stations, direct diversions from Lake Michigan, and eleven tributary streams or drainage areas. Even though treatment plant effluent concentrations meet the applicable standards and most reaches of the CWS meet the applicable water quality standards, Dissolved Oxygen (DO) standards are not met in the CWS during some periods. A Use Attainability Analysis was initiated to evaluate what water quality standards can be achieved in the CWS. The UAA team identified several DO improvement alternatives including new supplementary aeration stations. Because of the dynamic nature of the CWS, the DUFLOW model that is capable of simulating hydraulics and water quality processes under unsteady-flow conditions was used to evaluate the effectiveness of new supplementary aeration stations. This paper details the use of the DUFLOW model to size and locate supplementary aeration stations. In order to determine the size and location of supplemental aeration stations, 90% compliance with a 5 mg/l DO standard was used as a planning target. The simulations showed that a total of four new supplementary aeration stations with oxygen supply capacities ranging from 30 to 80 g/s would be sufficient to meet the proposed target DO concentration for the North Branch and South Branch of the Chicago River. There are several aeration technologies, two of which are already being used in the CWS, available and the UAA team determined that the total capital costs of the alternatives range from $35.5 to $89.9 million with annual operations and maintenance costs ranging from $554,000 to $2.14 million. Supplemental aeration stations have been shown to be a potentially effective means to improve DO concentrations in the CWS and will be included in developing an integrated strategy for improving water quality in the CWS.

Application of the contingent valuation method in a developing country: a case study of the Yusufeli dam in northeast Turkey.

Hydroelectric power plants and dams often play an important role in developing countries in terms of their contribution to economy. In accordance with the energy policies of Turkish Republic, Yusufeli Dam and Hydroelectric Power Plant in Northeastern Turkey have been initiated. In this study, the Contingent Valuation Method (CVM) was conducted in Yusufeli Village to determine the environmental costs of the Yusufeli Project. The purpose is to assess the willingness to pay (WTP) of Yusufeli Village residents for restoration of the environmental impacts of the dam project and also to investigate the underlying economic, psychological, and social motivations for WTP. WTP was calculated as US$761 per person which can further be used in the cost-benefit analysis. The results from the study suggest that application of the CVM in rural and urban areas located in the same region can show differences.