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Analysis of cutting forces is critical for understanding, control and optimization of machining operations. Table-dynamometers are the most common tools to measure the cutting forces directly. Workpiece geometry restrictions, high cost, altered dynamics, and limited frequency bandwidth are challenges associated with the direct measurement of the cutting forces using table-dynamometers. In this study, utilization of cost-effective spindle current sensors along with accelerometers is proposed to indirectly predict the cutting forces at the tool tip during milling operations. First, receptance coupling (RC) method is used to obtain dynamics between the tool tip and the accelerometers which are located on the spindle housing. The application of the RC method requires a series of impact hammer tests along with finite element simulations to identify the dynamics of machine tool structure. The measured accelerations are then integrated in frequency domain to obtain displacement of the spindle housing where the accelerometers are attached. A Kalman filter is then designed and applied to the displacement signals to reconstruct the AC component of the cutting forces. Next, the spindle current signals measured through the hall-effect sensors are processed to acquire the tangential and radial cutting forces. Finally, due to different frequency bandwidth of the measured signals through the accelerometers and hall-effect sensors, the reconstructed cutting forces are fused to improve the cutting force measurement accuracy. The proposed method is also verified by conducting a series of half and full-immersion milling tests, and the reconstructed results are compared to the measurements of a reference piezoelectric-based table-dynamometer. Results show that the proposed sensing scheme can predict the cutting forces effectively only at a fraction of the cost of traditional table-dynamometers without affecting overall workpiece geometries.

The application of photovoltaics (PV) has broadened into urban environments, which has different condition from rural environments, where generally PV power plants are installed. In order to develop solar cells for urban application, we should find the answers to two questions with dye-sensitized solar cells (DSSCs). One is current flat module design is really optimized for all solar cell types. The other is, if not, how to find the optimized module design. The power output from solar cells according to light incident angle has two types: one is linear to cosine law where the flat module and the other is non-linear to cosine law where 3-dimensional array of cell in the module can provide improved power output and energy density in given installed area. We have shown that DSSCs belongs to second case and non-linearity came under angled incident light by means of FDM calculation and experiments. In addition, by introducing patterns in the photoanode, light trapping effect maximized non-linearity to the oblique incident. We have arrayed the DSSCs cells into sub-modules with oblique angle. From this simple modification, from flat 2-dimensional array to 3-dimensional array of cells, the power output and energy density increased by 30–40%, respectively.

The dye-sensitized solar cell (DSSC) is a potential alternative to the widely used Si-based solar cell, with several advantages including higher energy conversion efficiency under weak and indirect illumination conditions, and the possibility of practical application in urban life due to their exterior characteristics. However, despite these advantages, the energy conversion efficiency of DSSCs has remained low at ∼10%. To improve the efficiency of DSSCs, research has been done on modifying the materials used in DSSC component parts, such as the photoanode, electrolyte, and counter electrode. Another approach is to modify the photoanode to increase the diffusion coefficient, reduce the recombination rate, and enhance the light behavior. One of the most popular methods for improving the efficiency of DSSCs is by trapping and dispersing the incident light using a scattering layer. Use of a scattering layer has shown various and interesting results, depending on the application, but it is currently used only in a simple form and there has been no deep research on the further potential of the scattering layer. In this study, the scattering center was introduced to maximize the effect of scattering. Light distribution near the scattering center, within or on the photoanode, was investigated using finite differential time domain (FDTD) numerical methods. Based on the FDTD analysis, an optimized, dome-shaped three-dimensional modified structure of a transparent photoanode with minimized scattering centers was introduced and indicated the possibility of modifying the photon distribution in the photoanode to enhance the performance of DSSCs. In addition to using the scattering center, we have introduced the structure of the dome-shaped three-dimensional structure to utilize the light distribution within the photoanode. This novel three-dimensional transparent photoanode and scattering center design increased the energy conversion efficiency of DSSCs from 6.3 to 7.2%. These results provide a foundation for investigating the role of the scattering center via further in-depth research. This new three-dimensional photoanode design provides a means to overcome the previous limitations on DSSC performance.

Photovoltaic panels based on crystalline Si solar cells are the most widely utilized renewable source of electricity, and there has been a significant effort to produce panels with a higher energy conversion efficiency. Typically, these developments have focused on cell-level device modifications to restrict the recombination of photo-generated charge carriers, and concepts such as back surface field, passivated emitter and rear contact (PERC), interdigitated back contact, and heterojunction with intrinsic thin layer solar cells have been established. Here, we propose quasi-Fermi level control using periodic local focusing of incident light by encapsulation with polydimethylsiloxane to improve the performance of solar cells at the module-level; such improvements can complement cell-level enhancements. Locally focused incident light is used to modify the internal quasi-Fermi level of PERC solar cells owing to the localized photon distribution within the cell. Control of the local focusing conditions induces different quasi-Fermi levels, and therefore results in different efficiency changes. For example, central focusing between fingers enhances the current density with a reduced fill factor, whereas multiple local focusing enhances the fill factor rather than the current density. Here, these effects were explored for various angles of incidence, and the total electrical energy production was increased by 3.6% in comparison to a bare cell. This increase is significant as conventional ethylene vinyl acetate-based encapsulation reduces the efficiency as short-wavelength light is attenuated. However, this implies that additional module-scale studies are required to optimize local focusing methods and their synergy with device-level modifications to produce advanced photovoltaics.

Sea-level rise is expected to cause saltwater intrusion into tidal freshwater wetlands. The resulting changes in the soil environment would likely cause shifts in plant and microbial communities and alter ecosystem functions. To simulate saltwater intrusion, we constructed a solar-powered automated irrigation system. The system consisted of holding tanks that were filled with freshwater or artificial brackish water during high tide. During low tide, the water was gravity-fed through solenoid valves and metered out to each plot. This system was controlled by an open-source microcontroller platform and built from off-the-shelf electronics at a cost of $1800. Porewater salinity in near-surface soils of the plots receiving brackish water was increased from freshwater to oligohaline levels within one month of operation and was maintained throughout the first summer of operation. This porewater manipulation led to changes in the plant community and in exchanges of carbon dioxide and methane between the marsh and atmosphere. The system has proven to be a reliable way of manipulating wetland salinity for studying changes in the physicochemical environment. With modifications, it could be used to manipulate nutrient loads, hydrology, and sediment supply in other wetland systems.

The rapid growth of portable smart devices demands wearable energy sources that convert environmental energy into electricity. Textile based solar cells are one of the most promising candidates. In particular, the rapid development of fiber or textile structured dye sensitized solar cells gives us an optimistic prospect. However, the fundamental printing process for textile based substrates, which is far different from that of TCO coated flat substrates, and the optimized morphology necessary to obtain the best performance have not yet been studied systemically. In this study, a new deposition method called the floating printing method is developed to obtain the uniform and controllable deposition of electrode materials on textile or wire type substrates to be utilized in a paste printing process. In addition, FEM analysis was performed to observe the effect of morphologies on short circuit currents and find an optimized morphology for the best energy conversion efficiency. As a result, we have found that the electron source or diffusion path enhanced electron transportation with a thin wire-top region and that a distorting diffusion path degraded the short circuit current with a thick wire-top region. TCO-free flexible DSSCs cells were prepared utilizing a metal textile substrate, a paper spacer and Pt coated carbon counter electrodes, and obtained a 4.16% energy conversion efficiency. The results can be extended to a 3-dimensional analysis considering various textile substrates.

Gradients of dissolved oxygen concentrations in stratified estuarine water columns directly influence microbial composition and metabolic pathways, resulting in vertical and axial chemical gradients of redox-active species. Understanding such microbial responses to changing geochemical conditions and elucidating the diversity of microbially-mediated processes are needed to comprehensively identify ecosystem functions. We tested the hypothesis that microbial metabolic processes in the vicinity of the oxic/anoxic interface in Chesapeake Bay would be elevated due to the coincidence of oxidized and reduced compounds. We measured rates of microbial redox processes associated with carbon cycles and quantified geochemical constituents. The transition from oxic to anoxic to oxic conditions was correlated with the pattern of dissolved nitrogen species, with the most reducing conditions comprising the highest concentrations of dissolved chemical compounds. The vertical distribution of community respiration was measured with changes in dissolved inorganic carbon concentrations and was related to water column stratification, with the highest median and variability (1.2 ± 1.4 μmol L−1 h−1) in the most stratified conditions. Rates of CO2 fixation under dark conditions, a measure of chemoautotrophy, were elevated at the base of oxyclines and significantly correlated with a gradient of density and some reduced compounds. Although vertical interpolation must be made with caution due to high vertical variability, chemoautotrophic production averaged 0.5 mmol m−2 h−1 from May to August and added 5.8% to autochthonous organic carbon production in the mesohaline Chesapeake Bay. Overall, our results suggest that anaerobic community metabolism and chemoautotrophy in the oxic/anoxic interface exert a small impact on estuarine carbon cycles.

Summary Intense annual spring phytoplankton blooms and thermohaline stratification lead to anoxia in Chesapeake Bay bottom waters. Once oxygen becomes depleted in the system, microbial communities use energetically favourable alternative electron acceptors for respiration. The extent to which changes in respiration are reflected in community gene expression have only recently been investigated. Metatranscriptomes prepared from near-bottom water plankton over a 4-month time series in central Chesapeake Bay demonstrated changes consistent with terminal electron acceptor availability. The frequency of respiration-related genes in metatranscriptomes was examined by BLASTx against curated databases of genes intimately and exclusively involved in specific electron acceptor utilization pathways. The relative expression of genes involved in denitrification and dissimilatory nitrate reduction to ammonium were coincident with changes in nitrate, nitrite and ammonium concentrations. Dissimilatory iron and manganese reduction transcript ratios increase during anoxic conditions and corresponded with the highest soluble reactive phosphate and manganese concentrations. The sulfide concentration peaked in late July and early August and also matched dissimilatory sulfate reduction transcript ratios. We show that rather than abrupt transitions between terminal electron acceptors, there is substantial overlap in time and space of these various anaerobic respiratory processes in Chesapeake Bay.

IMPORTANCE: Amyloid-β positron emission tomography (PET) imaging allows in vivo detection of fibrillar plaques, a core neuropathological feature of Alzheimer disease (AD). Its diagnostic utility is still unclear because amyloid plaques also occur in patients with non-AD dementia. OBJECTIVE: To use individual participant data meta-analysis to estimate the prevalence of amyloid positivity on PET in a wide variety of dementia syndromes. DATA SOURCES: The MEDLINE and Web of Science databases were searched from January 2004 to April 2015 for amyloid PET studies. STUDY SELECTION: Case reports and studies on neurological or psychiatric diseases other than dementia were excluded. Corresponding authors of eligible cohorts were invited to provide individual participant data. DATA EXTRACTION AND SYNTHESIS: Data were provided for 1359 participants with clinically diagnosed AD and 538 participants with non-AD dementia. The reference groups were 1849 healthy control participants (based on amyloid PET) and an independent sample of 1369 AD participants (based on autopsy). MAIN OUTCOMES AND MEASURES: Estimated prevalence of positive amyloid PET scans according to diagnosis, age, and apolipoprotein E (APOE) ε4 status, using the generalized estimating equations method. RESULTS: The likelihood of amyloid positivity was associated with age and APOE ε4 status. In AD dementia, the prevalence of amyloid positivity decreased from age 50 to 90 years in APOE ε4 noncarriers (86% [95% CI, 73%-94%] at 50 years to 68% [95% CI, 57%-77%] at 90 years; n = 377) and to a lesser degree in APOE ε4 carriers (97% [95% CI, 92%-99%] at 50 years to 90% [95% CI, 83%-94%] at 90 years; n = 593; P

Dye sensitize solar cells (DSSCs) have been considered as the promising alternatives silicon based solar cell with their characteristics including high efficiency under weak illumination and insensitive power output to incident angle. Therefore, many researches have been studied to improve the energy conversion efficiency of DSSCs. However the efficiency of DSSCs are still trapped at the around 10%. In this study, micro-scale hexagonal shape patterned photoanode have proposed to modify light distribution of photon. In the patterned electrode, the appearance efficiency have been obtained from 7.1% to 7.8% considered active area and the efficiency of 12.7% have been obtained based on the photoanode area. Enhancing diffusion of electrons and modification of photon distribution utilizing the morphology of the electrode are major factors to improving the performance of patterned electrode. Also, finite element method analyses of photon distributions were conducted to estimate morphological effect that influence on the photon distribution and current density. From our proposed study, it is expecting that patterned electrode is one of the solution to overcome the stagnant efficiency and one of the optimized geometry of electrode to modify photon distribution. Process of inter-patterning in photoanode has been minimized.

To assess the effects of seasonal oxygen transition on microbial metabolism, we measured spatiotemporal changes in total dissolved inorganic carbon, respiratory products, and geochemical constituents in the mesohaline region of Chesapeake Bay from May to October 2010. Vertical redox zonation was examined, and a spatial transect survey was also conducted from the southern to northern limit of the mesohaline region in July providing an alternative approach for assessing the temporal dynamics of oxygen transition. The transitions from oxic to hypoxic to anoxic and back to oxic were illustrated by the pattern of nitrogen redox species. Respiration, measured from changes in total dissolved inorganic carbon (∆DIC) and dissolved oxygen (∆DO) during incubations, had an average respiratory quotient (∆DIC/∆DO) of 1.04 ± 0.06 under oxic conditions and 1.58 ± 0.48 under hypoxic conditions. The difference in the respiratory quotients suggested that oxygen-based respiration measurements would underestimate community respiration rates in hypoxic conditions. In the present study, we observed within the surface-mixed layer three- to sevenfold differences in temporal and vertical variation of community respiration, while net respiration across oxyclines and anaerobic respiration in deep waters had lower rates and variability. In some anoxic samples, there was a net decrease in dissolved inorganic carbon that was exacerbated with experimental augmentation of terminal electron acceptors. Potential carbon fixation rates of chemoautotrophs within and below oxyclines were estimated and ranged from 0.63 to 116.9 mg C m−2 day−1 depending on growth conditions. These results indicate that anaerobic metabolism during the seasonal anoxic transition and at oxic/anoxic interface can play an important role in the estuarine carbon cycle.

We used metatranscriptomics to study the gene transcription patterns of microbial plankton (0.2 to 64 μm) at a mesohaline station in the Chesapeake Bay under transitions from oxic to anoxic waters in spring and from anoxic to oxic waters in autumn. Samples were collected from surface (i.e., above pycnocline) waters (3 m) and from waters beneath the pycnocline (16 to 22 m) in both 2010 and 2011. Metatranscriptome profiles based on function and potential phylogeny were different between 2010 and 2011 and strongly variable in 2011. This difference in variability corresponded with a highly variable ratio of eukaryotic to bacterial sequences (0.3 to 5.5), reflecting transient algal blooms in 2011 that were absent in 2010. The similarity between metatranscriptomes changed at a lower rate during the transition from oxic to anoxic waters than after the return to oxic conditions. Transcripts related to photosynthesis and low-affinity cytochrome oxidases were significantly higher in shallow than in deep waters, while in deep water genes involved in anaerobic metabolism, particularly sulfate reduction, succinyl coenzyme A (succinyl-CoA)-to-propionyl-CoA conversion, and menaquinone synthesis, were enriched relative to in shallow waters. Expected transitions in metabolism between oxic and anoxic deep waters were reflected in elevated levels of anaerobic respiratory reductases and utilization of propenediol and acetoin. The percentage of archaeal transcripts increased in both years in late summer (from 0.1 to 4.4% of all transcripts in 2010 and from 0.1 to 6.2% in 2011). Denitrification-related genes were expressed in a predicted pattern during the oxic-anoxic transition. Overall, our data suggest that Chesapeake Bay microbial assemblages express gene suites differently in shallow and deep waters and that differences in deep waters reflect variable redox states.

Estuarine turbidity maxima (ETM) play an important role in zooplankton and larval fish productivity in many estuaries. Yet in many of these systems, little is known about the food web that supports this secondary production. To see if phytoplankton have the potential to be a component of the ETM food web in the Chesapeake Bay estuary a series of cruises were carried out to determine the biomass distribution and floral composition of phytoplankton in and around the ETM during the winter and spring using fluorometry, high-performance liquid chromatography (HPLC), and microscopy. Two distinct phytoplankton communities were observed along the salinity gradient. In lower salinity waters, biomass was low and the community was composed mostly of diatoms, while in more saline waters biomass was high and the community was composed mostly of mixotrophic dinoflagellates, which were often concentrated in a thin layer below the pycnocline. Phytoplankton biomass was always low in the ETM, but high concentrations of phytoplankton pigment degradation products and cellular remains were often observed suggesting that this was an area of high phytoplankton mortality and/or an area where phytoplankton derived particulate organic matter was being trapped. These results, along with a box model analysis, suggest that under certain hydrodynamic conditions phytoplankton derived organic matter can be trapped in ETM and potentially play a role in fueling secondary production.

Textile-structured solar cells are frequently discussed in the literature due to their prospective applications in wearable devices and in building integrated solar cells that utilize their flexibility, mechanical robustness, and aesthetic appearance, but the current approaches for textile-based solar cells—including the preparation of fibre-type solar cells woven into textiles—face several difficulties from high friction and tension during the weaving process. This study proposes a new structural concept and fabrication process for monolithic-structured textile-based dye-sensitized solar cells that are fabricated by a process similar to the cloth-making process, including the preparation of wires and yarns that are woven for use in textiles, printed, dyed, and packaged. The fabricated single-layered textile-based dye-sensitized solar cells successfully act as solar cells in our study, even under bending conditions. By controlling the inter-weft spacing and the number of Ti wires for the photoelectrode conductor, we have found that the performance of this type of dye-sensitized solar cell was notably affected by the spacing between photoelectrodes and counter-electrodes, the exposed areas of Ti wires to photoelectrodes, and photoelectrodes’ surface morphology. We believe that this study provides a process and concept for improved textile-based solar cells that can form the basis for further research.

Considering the current application of fullerenes in the field of organic semiconductor devices, the highly crystalline or single crystal fullerene nanostructures with controlled shape and size contains some breakthrough for improved efficiency. Recently, fullerene 1-dimensional nanostructures, including nanowhiskers and nanotubes, become attractive kind of materials since the development of liquid-liquid interface precipitation (LLIP) process. The LLIP process has critical advantage; the fabrication of highly crystalline, even single crystal, fullerene 1-dimensional nanostructures with simple apparatus. However, the fabrication fullerene 1-dimensional structures by LLIP process requires long process time from one day to several days. In order to overcome this drawback, a modified process from conventional LLIP process is suggested. In the modified LLIP process, the nucleation step and growth step were divided. For the nucleation step, saturated fullerene solution is mixed with small amount of alcohols such as 2-propanol or ethanol. For the controlled growth step, the fullerenes in the nucleated solution are precipitated by addition of alcohol, which is injected to the bottom of the solution with controlled flow rate. In this modified process, the shape of the precipitated fullerene crystals is critically dependent on the nucleation steps and the size is dependent on the precipitation rate. By combination of proper nucleation step and growth rate, a well defined fullerene 1-dimensional structures, of 200-500 nm width and of hundreds microm length can be fabricated within two hours. In addition, by controlling injection rate and degree of supersaturation, several types of 1-dimensional structures including micro-tubes can be prepared and, by changing solvent and alcohol, several shape of C60 crystals including polyhedral particles and plates can be prepared.

Efficient dye-sensitized solar cells (DSCs) were realized by using multiwalled carbon nanotubes (CNTs) as the counter-electrode catalyst. The catalytic layers were produced from an aqueous paste of mass-produced raw CNTs with carboxymethylcellulose polymer by low-temperature (70 degrees C) drying. We found that the highly disordered CNTs played the important role of increasing the fill factor of DSCs with electrolytes including large molecules and that the presence of Li(+) as the counter charges for I(3)(-)/I(-) redox couples reduced the chemical stability when using the CNT catalyst. Our experiments showed that by replacing the conventional Pt catalyst and Li(+)-based electrolyte with the proposed CNT catalyst and an electrolyte containing 1-butyl-3-methylimidazolium cations instead of Li(+), the energy conversion efficiency increased from 6.51% to 7.13%. This result suggests that highly defective CNT catalysts prepared by low-temperature drying are viable cost-effective alternatives for DSCs, as long as the electrolytes composition is optimized.

Since their initial invention, dye-sensitized solar cells (DSSCs) have offered cost-effective photovoltaic systems. For their counter electrodes, DSSCs generally employ Pt nanoparticles. However, Pt is expensive, rare, and already widely in demand as catalyst in various chemical and electrochemical fields. Substitutes for Pt have been sought among carbon materials, such as activated carbon, carbon black, and carbon nanotubes. Carbon nanotubes (CNTs) are the most appealing candidates, because of their favorable electrochemical catalytic activities. Unfortunately, as with other carbon materials, CNTs cannot provide high charge exchange currents. To obtain performances comparable to Pt counter electrodes, large surface areas are required, resulting in thick electrodes. We have found that transparent Pt-free counter electrodes suitable for DSSCs can be prepared using MWCNT micro-balls deposited on transparent substrates. The deposition density (i.e., the number of CNT micro-balls per unit area) can be controlled, allowing transparency and DSSC performance to be tuned. For a counter electrode transparency of 70%, the efficiency of a DSSC using CNT micro-balls is more than 80% of one using Pt nanoparticles. The prepared CNT micro-balls can be usefully applied in other electrochemical devices, such as battery and supercapacitors.

Large dye-sensitized solar cells (DSCs) are usually fabricated as module types instead of single cell types, because the overall efficiency of an area-expanded single DSC is decreased by its large surface resistances and low fill factor (FF). The general DSC module designs are the parallel grid, series interconnect, and series monolithic types. The W-series interconnect type of module has some advantages, such as its easy fabrication and simple structure. Moreover, it also avoids the reduction in the FF. However, it has an efficiency imbalance between the single cells, because of the discrepancy in their luminous intensity. Therefore, the fabrication of the W-series interconnect type of module will be cost-effective only if the problem of its efficiency imbalance is solved. In this study, the thickness of the Pt layer, which has a very high reflection rate, and that of the electrolyte layer are minimized and the transmitted light is reflected by a metallic thin film in order to increase the number of photons absorbed by the dye molecules in the module. As a result, the performance of the efficiency-balanced W-module is improved by approximately 1% as compared to that of the conventional module.

The counter electrode widely used in DSC (Dye-sensitized solar cells) is constructed of a conducting glass substrate coated with a Pt film, in which the platinum acts as a catalyst. The characteristics of the platinum electrode depend strongly on the fabrication process and the electrode's surface condition. In this study, Pt counter electrodes were deposited by radio frequency (RF) sputtering with 6.7 × 10 − 1 Pa Ar, RF power of 120 W and substrate temperature of 100 °C. The surface morphology of Pt electrodes was investigated using field emission scanning electron microscopy and atomic force microscopy. Comparison of samples prepared by RF sputtering and RF magnetron sputtering showed that the surface of the RF sputter deposited electrode had a larger surface area resulting in more effective catalytic characteristics. Finally, an open voltage of 4.8 V, a short circuit current of 569 mA and a photoelectric conversion efficiency of approximately 3.6% were achieved for cells composed of 30 DSC units of 6 cm × 4 cm DSC units with 6 cells in series and 5 cells in parallel.

Usually, the calculation of the optical generation in solar cell simulations is based on the assumption of constant absorption coefficients. Under certain circumstances, however, the absorption coefficient may depend on the light intensity, for example, if the absorbing material suffers from optical saturation. In this work, we present a simple model taking into account a saturable absorber, which can be easily implemented in standard optical simulation models.

Increasing demands for wearable energy sources and highly flexible, lightweight photovoltaic devices have stimulated the development of textile-structured solar cells. However, the former approach of wire-type solar cell fabrication, followed by weaving of these devices, has had limited success, due to device failure caused by high friction forces and tension forces during the weaving process. To overcome this limitation, we present a new approach for textile solar cell fabrication, in which dye-sensitized solar cell (DSSC) electrodes are incorporated into the textile during the weaving process, using the textile warp as a spacer to maintain the DSSC structure. Porous, dye-loaded TiO2-coated holed metal ribbon and Pt nanoparticle-loaded carbon yarn were used as the photoanode and counterelectrode, respectively. The highly flexible textile-based solar cell was fabricated using a common weaving process with a loom. The inserted DSSCs in the textile demonstrated an energy conversion efficiency of 2.63% (at 1 sun, 1.5 A.M.). Our results revealed that additional performance enhancement was possible by considering other electrode materials and textile structures, as well as where and how the DSSC electrodes are inserted. In addition, we demonstrated that the inserted DSSCs could be electrically connected using a parallel configuration.

The flow characteristics and particle collection efficiencies of a long-cone cyclone with twice as long a conical section as that of the Stairmand cyclone were analyzed numerically to see the effect of the cylinder shape on the flow and collection performance. The three-dimensional flow field is obtained using the commercial package, FLUENT, and particle paths are calculated with the Lagrangean integration of the particle equation of motion. A number of turbulence models were tested, and it was confirmed that only the second-order Reynolds stress model gave reasonable results for the flow velocity profile. It is also shown that the shape of the core-annulus interface is important for the overall flow and collection characteristics, and the interface shape is in turn strongly affected by the distance from the bottom of the inlet to the cylinder-cone junction. By adjusting the diameters of the cylinder and the view finder with the mass flux and inlet area kept constant, the shape of the core-annulus interface could be changed. As a result, the short-circuiting of the inlet flow to the view finder and the total pressure drop could be reduced by properly adjusting the cylinder body diameter.

This study examined whether clients' positive or negative self-disclosure and sex affected counselors' evaluation of the clients. 80 counselors (30 certified, 45 master's and five doctoral trainees; six men and 74 women), after viewing a videotaped counseling interview in which the client self-disclosed either largely positive or negative contents responded to the Clinical Impression Scale which contained 8 clinical characteristics of clients (assertiveness, overall coping skills, anxiety, attitude toward counseling, motivation to change, self-esteem, insight, and depression). When the client self-disclosed largely negative content about self, counselors evaluated male client more negatively, i.e., less assertive, poor coping skills, higher anxiety, more negative attitude toward counseling, less eager to change, lower self-esteem, less insight, and higher depression) than female client. However, when the client self-disclosed largely positive content, there was no statistically significant sex difference between the two groups. The implications are discussed.

Based on the notion of positive psychology, the interrelationships among peer-rated mental health, social acceptance and irrational beliefs were examined using Korean youth. We predicted that adolescents who were rated by their peers to be relatively more mentally healthy, compared to those who were rated to be less mentally healthy, would (a) receive higher social acceptance from peers and (b) report fewer irrational beliefs. 476 adolescents (252 boys and 224 girls; M age =16.7 yr., SD = .46), all recruited from a single high school in an upper middle-class area in Seoul, Korea, rated each others' mental health in five areas of mental health, i.e., concern for others, contentment with life, creativity and industry, good interpersonal relationships and ability to cope with stressful situations and social acceptance and responded to a questionnaire measuring irrational beliefs. Analysis showed that those adolescents who were rated by their peers to be more mentally healthy received higher social acceptance from those peers than those rated as less mentally healthy; however, this effect size was small. Implications of the study are discussed.

Features of flow and particle transport in a single axisymmetric alveolated tube with 30 cells in the presence of wall motion are analyzed numerically for flow conditions typically found in the Aerosol Bolus experiments: the tracheal breathing flowrate of 250 ml / s and breathing period of 8 s . Different characteristics of particle transport between the alveolated and the straight tube are explained based on the details of flow and particle motion. For both expansion and contraction the axial motion of particles in an alveolated tube is smaller than in a straight tube due to the decelerated flow in the alveolated region. In an expanding alveolated tube particles get accumulated near the wall and some particles enter alveolus, which make dispersion larger than that in an expanding straight tube. In a contracting alveolated tube particles consistently move toward the tube center, and flow velocity profile is much blunter than the parabolic one, making dispersion smaller than in a contracting straight tube. In the presence of wall motion, the difference in particle transport between alveolated tube and straight tube becomes larger as Strouhal number is increased. Limitations and physiological implications of the results are discussed.

The dispersion of an aerosol bolus for one complete respiration cycle is analyzed numerically, using a lung airway model with four successive bifurcations. Unsteady Navier–Stokes equation and diffusion equation are solved by CFX-F3D, an FVM commercial code. Reynolds number based on the inlet conditions is varied between 0.533 and 24, and Womersley number between 0.0915 and 0.495, which correspond to the flow conditions in the 10th to the 18th generations of Weibel model at typical conditions of bolus experiments (tracheal breathing rate of 0.25 l / s , respiration period of 8 s and 0.8 μm particle size). The dispersion characteristics during the inhalation period are seen the same as in steady inhalation, the total dispersion increasing monotonically with inhalation. When flow direction is reversed to exhalation, bolus dispersion decreases with exhalation at first, but comes to increase again at a rate almost equal to that for steady exhalation after a certain amount of exhalation. The maximum reduction of bolus dispersion after flow reversal is comparable to the increase of bolus dispersion in the last generation just before flow reversal.

A Korean version of the Consortium to Establish a Registry for Alzheimer’s Disease Assessment Packet (CERAD-K) was created. The English-American version of CERAD clinical and neuropsychological assessment batteries was translated into Korean, and the psychometrical properties of the cognitive tests in the CERAD-K were established. In the translation, including back-translation, the basic structures of all measures in the original CERAD batteries were maintained. The CERAD-K was administered in a standardized manner to 106 dementia patients (aged 70.4 � 8.1 years), including 78 Alzheimer’s disease (AD) patients, and 186 controls (aged 68.4 � 4.6 years) who were recruited from 3 university hospitals and 2 elderly welfare centers. The cognitive tests in the CERAD-K successfully differentiated controls from the dementia patients and from the AD patients. They also showed substantial interrater reliability and 1-month test-retest reliability. The CERAD-K is an equally reliable and valid equivalent for the English version of the CERAD clinical and neuropsychological assessment batteries. HE Consortium to Establish a Registry for Alzheimer’s Disease (CERAD) developed the standardized clinical

Intense annual spring phytoplankton blooms and thermohaline stratification lead to anoxia in Chesapeake Bay bottom waters. Once oxygen becomes depleted in the system, microbial communities use energetically favourable alternative electron acceptors for respiration. The extent to which changes in respiration are reflected in community gene expression have only recently been investigated. Metatranscriptomes prepared from near-bottom water plankton over a 4-month time series in central Chesapeake Bay demonstrated changes consistent with terminal electron acceptor availability. The frequency of respiration-related genes in metatranscriptomes was examined by BLASTx against curated databases of genes intimately and exclusively involved in specific electron acceptor utilization pathways. The relative expression of genes involved in denitrification and dissimilatory nitrate reduction to ammonium were coincident with changes in nitrate, nitrite and ammonium concentrations. Dissimilatory iron and manganese reduction transcript ratios increase during anoxic conditions and corresponded with the highest soluble reactive phosphate and manganese concentrations. The sulfide concentration peaked in late July and early August and also matched dissimilatory sulfate reduction transcript ratios. We show that rather than abrupt transitions between terminal electron acceptors, there is substantial overlap in time and space of these various anaerobic respiratory processes in Chesapeake Bay.

Textile forms of solar cells possess special advantages over other types of solar cells, including their light weight, high flexibility, and mechanical robustness. Recent demand for wearable devices has promoted interest in the development of high-efficiency textile-based solar cells for energy suppliers. However, the weaving process occurs under high-friction, high-tension conditions that are not conducive to coated solar-cell active layers or electrodes deposited on the wire or strings. Therefore, a new approach is needed for the development of textile-based solar cells suitable for woven fabrics for wide-range application. In this report, we present a highly flexible, efficient DSSC, fabricated by sewing textile-structured electrodes onto casual fabrics such as cotton, silk, and felt, or paper, thereby forming core integrated DSSC structures with high energy-conversion efficiency (~5.8%). The fabricated textile-based DSSC devices showed high flexibility and high performance under 4-mm radius of curvature over thousands of deformation cycles. Considering the vast number of textile types, our textile-based DSSC devices offer a huge range of applications, including transparent, stretchable, wearable devices.

The dispersion of an aerosol bolus in models of lung airway with one, two or three bifurcations was analyzed numerically for steady expiratory flow. The broadening of the concentration peak was converted into an effective diffusivity Deff. It was possible to express local Deff for each generation as an approximately linear function of local mean flow velocity u and diameter d. During exhalation, unlike in inhalation, the average proportional constant Deff/u0d0 does not change over several generations. In exhalation Deff for particles is 30% lower than for gases just as in inhalation. Results of the present study on total dispersion were in excellent agreement with experiments when the difference in diffusivity between gases and particles were corrected for.

The dispersion of an aerosol bolus in a model lung airway was analyzed numerically. Doubly bifurcated tube models were used in order to eliminate the sensitive effect of the inlet velocity profile on the entire flow field. Navier–Stokes equation and diffusion equation were solved by CFX-F3D, an FVM commercial code, and the broadening of concentration peak was converted into an effective diffusivity D eff . The local D eff for each generation could be expressed approximately as a linear function of local mean flow velocity and diameter, but secondary flow makes the relationship nonlinear. It was found that D eff increases toward downstream due to streaming, and that D eff for particles is 35% lower than for gases. Simulation results were in good agreement with experiments by Scherer when the difference in diffusivity between gases and particles was corrected for.

Objective Although apolipoprotein (APOE) e4 allele is a well-established risk factor for late-onset Alzheimer disease (AD), the mechanism of its effects on AD pathogenesis is not fully understood. We aimed to investigate the effects of APOE genotype on regional cerebral glucose metabolism in cognitively normal (CN) elderly. We further tried to elucidate whether or not such effects are associated with beta-amyloid protein (Aβ) deposition. Methods 31 CN elderly participants underwent clinical examination, a range of neuropsychological tests, APOE genotyping, and Pittsburgh compound-B- and fluorodeoxyglucose-PET scans. Results 17 APOE e4 carriers and 15 non-carriers were included. Both hypometabolic and hypermetabolic regions were observed in e4 carriers compared with noncarriers when age, education, and sex were controlled. When the degree of global cerebral Aβ deposition was adjusted, the hypometabolic regions in the temporo-parietal area (i.e., BA 22 and 39) largely disappeared, whereas the hypermetabolic regions persisted in medial frontal and anterior temporal areas (i.e., BA 38, 11, and 39). Behaviorally, verbal episodic memory scores of APOE e4 carriers were slightly lower than those of noncarriers, though still within normal range. Conclusions Our findings indicate that decreased cerebral glucose metabolism in the temporoparietal junction associated with APOE e4 in CN elderly appears to be mediated by Aβ deposition, and the effect of APOE e4 on hypermetabolism in the frontal and anterior temporal regions is independent of Aβ and may be associated with presence of compensatory mechanism in CN elderly with the e4 allele.

In an effort to identify the key mechanisms controlling biological productivity and food web structure in the Chesapeake Bay estuarine turbidity maxima (ETM), we measured plankton community metabolism on a series of surveys in the upper Chesapeake Bay during the winter and spring of 2007 and 2008. Measured quantities included primary production, bacterial production, planktonic community respiration, and algal pigment concentrations. These measurements revealed a classic minimum in photosynthesis in the vicinity of the ETM. Temporal variability in plankton community metabolism, primary production, respiration, and bacterial production, were highest in the southern oligohaline region down-estuary of the ETM, and appeared to be driven by dynamic bio-physical interactions. Elevated primary production and community respiration in this region were often associated with the presence of mixotrophic dinoflagellates. The dinoflagellate contribution to primary production and respiration appeared to be particularly large as a result of their mixotrophic capabilities, which allow them to obtain energy both autotrophically and heterotrophically. This study suggests that mixotrophic dinoflagellates play a key role in pelagic food web in the oligohaline region of Chesapeake Bay supplying most of the labile organic matter during late winter and spring and also providing a vector for transferring microbial production to mesozooplankton.

This paper describes a software safety analysis for a software code that is installed at an Automatic Test and Interface Processor (ATIP) in a digital reactor protection system. For the ATIP software safety analysis, an overall safety analysis is at first performed over the ATIP software architecture and modules, and then a detailed safety analysis based on the software FMEA (Failure Modes and Effect Analysis) method is applied to the ATIP program. For an efficient analysis, the software FMEA is carried out based on the so-called failure-mode template extracted from the function blocks used in the function block diagram (FBD) for the ATIP software. The software safety analysis by the software FMEA, being applied to the ATIP software code which has been integrated and passed through a very rigorous system test procedure, is proven to be able to provide very valuable results (i.e., software defects) which could not be identified during various system tests.Copyright © 2009 by ASME

A new self-report scale, the Altruism Scale for Adults, of 28 items was developed. 14 items were from the Altruism subscale of Wrightsman's Philosophies of Human Nature Scale, and the other 14 items were newly constructed. The scale, anchored by 1: true or 2: false, was administered to 592 Korean men and women in eight subgroups. Cronbach alpha internal consistency was .89, and test-retest reliabilities ( n = 52) over 1 and 5 wk. were .90 and .80, respectively. Campbell and Fiske's 1959 multitrait-multimethod analysis showed satisfactory convergent and discriminant validities. Overall results were promising for use of the scale in research and for practical purposes.

Clients' causal explanations for recalled important or helpful events between those of early and of late sessions of counseling interview have been examined. We predicted that (a) for clients' recalled important or helpful events, there will be more internal attribution in late than in early sessions and (b) clients' evaluation of counseling sessions would be positively related to their internal attribution of the recalled important or helpful events. Data were generated from 84 sessions of therapy, with 12 counselor-client dyads conducting seven sessions of therapeutic interviews each. Immediately after each interview, clients were requested to recall and explain the most important or helpful events that happened during the session. Clients' causal explanations of the events were analyzed by two trained judges. Results showed no statistically significant differences in frequencies of internal attribution. Similarly, internal attribution did not covary with clients' evaluation of counseling sessions. The implications of the results are discussed.

Because dementia is a chronic debilitating disease, there are the issues of the difficulty in continuous long-term care and limited accessibility to medical service. We developed the telemedicine system for dementia patients and aimed to examine the acceptance, reliability, and clinical outcome of our telemedicine service. We established the Dementia Telemedicine Center in connection with two recipient sites in 1996. The reliability of the center, which provides telemedicine, tele-education, and telecounseling services, was tested by comparing assessment via our system with in-person assessment, and the clinical outcome was assessed by rating the changes of behavioral symptoms. There have been 140 registered patients for 2 years. The general acceptance of our system by the patients and caregivers was good, and the consistency rates between the assessment via our telemedicine system and in-person assessment ranged from 76% to 89%. A considerable proportion of dementia patients in nursing homes (46%) showed relative clinical improvements through our service. Our telemedicine system seems to be reliable and effective for the assessment and care of dementia patients. Our future direction is to promote our system as a core model of the home-based care system for dementia patients.

A survey of state units on aging revealed that 43 states and the District of Columbia provide some weekend home delivered meals. In most states meals were provided in only a few areas. There is no national system for reporting weekend delivery. Very few states have data on the extent of weekend meal service. A pilot study to determine the need for home delivered meals indicated that persons receiving home delivered meals 5 days a week were more likely to have an insufficient dietary intake of protein, thiamin, riboflavin, calcium, iron, and phosphorus on weekends than weekdays.