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Objectives: Cisplatin (CISP) is an effective chemotherapy used in the treatment of various types of cancer, but it causes nephrotoxicity and other adverse effects. Thymoquinone (THY) is an effective anti-inflammatory and antioxidant compound, which might protects against many chemotherapies associated toxicities. However, THY applications are hindered by its poor solubility and low bioavailability. This study evaluated the efficacy of a novel nanoparticle (NP) encapsulting THY to overcome its poor solubility, enhance its bioavilability, efficacy for the protection against CISP-induced nephrotoxicity in an Ehrlich solid carcinoma (ESC) mice model. Methods: Four treatment groups were included: 1) control, 2) tumour, 3) CISP, and 4) CISP + NP THY. Results: The results showed that NP THY was effective in preventing CISP-induced kidney toxicity in ESC mice and improved its function and pathology. NP THY effectively ameliorated CISP-induced oxidative stress conditions in the kidney tissue via increasing the levels of antioxidants both non-enzymatic (GSH) and enzymatic (SOD and CAT). NP THY, also, significantly reduced CISP-induced kidney inflammation by reducing TNF-α, IL-1β, and NF-kB levels. NP THY didn’t hinder the antitumor activity of CISP as shown by tumour weight and histological examination data. Conclusions: In conclusion, NP THY could be an adjuvant therapy to CISP cancer treatment to prevent associated nephrotoxicity and other adverse effects without compromising CISP antitumor efficacy.

HEV is the most causative agent of acute viral hepatitis globally. HEV causes acute, chronic, and extrahepatic manifestations. Chronic HEV infection develops in immunocompromised patients such as organ transplant patients, HIV-infected patients, and leukemic patients. The source of chronic HEV infection is not known. Also, the source of extrahepatic manifestations associated with HEV infection is still unclear. Hepatotropic viruses such as HCV and HBV replicate in peripheral blood mononuclear cells (PBMCs) and these cells become a source of chronic reactivation of the infections in allograft organ transplant patients. Herein, we reported that PBMCs and bone marrow-derived macrophages (BMDMs), isolated from healthy donors (n = 3), are susceptible to HEV in vitro. Human monocytes (HMOs), human macrophages (HMACs), and human BMDMs were challenged with HEV-1 and HEV-3 viruses. HEV RNA was measured by qPCR, the marker of the intermediate replicative form (ds-RNA) was assessed by immunofluorescence, and HEV capsid protein was assessed by flow cytometry and ELISA. HEV infection was successfully established in primary HMOs, HMACs, and human BMDMs, but not in the corresponding cells of murine origin. Intermediate replicative form (ds RNA) was detected in HMOs and HMACs challenged with HEV. The HEV load was increased over time, and the HEV capsid protein was detected intracellularly in the HEV-infected cells and accumulated extracellularly over time, confirming that HEV completes the life cycle inside these cells. The HEV particles produced from the infected BMDMs were infectious to naive HMOs in vitro. The HEV viral load was comparable in HEV-1- and HEV-3-infected cells, but HEV-1 induced more inflammatory responses. In conclusion, HMOs, HMACs, and human BMDMs are permissive to HEV infection and these cells could be the source of chronic and recurrent infection, especially in immunocompromised patients. Replication of HEV in human BMDMs could be related to hematological disorders associated with extrahepatic manifestations.

Breast cancer is the most common neoplastic disorder diagnosed in women. The main goal of this study was to explore the effect of melatonin against breast cancer metastasis and compared this with the actions of taxol (a well-known chemotherapeutic drug), and the impact of their combination against breast cancer metastasis. Melatonin showed no cytotoxic effect while taxol showed antiproliferative and cytotoxic effects on MCF-7 and MDA-MB-231 cells. Furthermore, melatonin inhibited the generation of reactive oxygen species. Melatonin and taxol clearly decreased cell migration and invasion at low doses, especially those matching the normal physiological concentration at night. Melatonin and taxol markedly reduced DJ-1 and ID-1 and increased KLF17 messenger RNA and protein expression levels. The present results also showed that melatonin and taxol induced GSK3-β nuclear and Snail cytosolic localization. These changes were accompanied by a concurrent rise in E-cadherin expression. The above data show that normal levels of melatonin may help in preventing breast cancer metastasis through inhibiting DJ-1/KLF17/ID-1 signaling pathway. The combination of melatonin and taxol is a potent candidate against breast cancer metastasis, better than using melatonin or taxol as a single drug.

Paclitaxel (taxol) is an important agent against many tumours, including breast cancer. Ample data documents that paclitaxel inhibits breast cancer metastasis while others prove that paclitaxel enhances breast cancer metastasis. The mechanisms by which paclitaxel exerts its action are not well established. This study focuses on the effect of paclitaxel, particularly the low doses on breast cancer metastasis and the mechanisms that regulate it. Current results show that, paclitaxel exerts significant cytotoxicity even at low doses in both MCF-7 and MDA-MB-231 cells. Interestingly, paclitaxel significantly inhibits cell invasion and migration, decreases Snail and increases E-cadherin mRNA expression levels at the indicated low doses. Furthermore, paclitaxel-inhibiting breast cancer metastasis is associated with down-regulation of DJ-1 and ID-1 mRNA expression level with a concurrent increase in KLF17 expression. Under the same experimental conditions, paclitaxel induces KLF17 and concurrently represses ID-1 protein levels. Our results show for the first time that paclitaxel inhibits breast cancer metastasis through regulating DJ-1/KLF17/ID-1 signalling pathway; repressed DJ-1 and ID-1 and enhanced KLF17 expression.

Cool/white roofing systems use paints and membranes with high solar reflectivity to reflect a portion of the incident solar radiation resulting in lowering the temperature of the exterior surfaces in respect of the conventional/black roofing systems. This study focuses on the energy performance of roofing system that is being used in buildings of the Gulf Cooperation Council countries when this roof is exposed to a hot and humid climatic conditions in Saudi Arabia. The long-term moisture performance of the white and black roofing systems were investigated in a previous study in which the results showed that no risk of condensation and mould growth occurred in the roofs with different values of solar reflectivity of the rooftop and different initial construction moisture. With the same environmental conditions that were used in the previous study, the focus of this paper is on assessing the energy performance of white and black roofing systems for a wide range of: (a) thermal insulation thickness, and (b) solar reflectivity of the rooftop. Also, considerations are given in this study to develop a practical design tool that can easily be used by building engineers and architects for determining all pairs of the insulation thickness and the corresponding solar reflectivity of the reflective roofing materials/coatings that resulted in the same levels of the energy performance as those for the black roofing systems of thicker insulation thickness. The results of this study along with the developed practical design tool can be used in future to upgrade the Saudi building code to allow using less insulation in the roofs if white roofing systems are installed.

The long-term performance in respect to moisture management within any wood frame wall assembly depends on the hygrothermal response of the wall to local climate moisture loads. Estimating the wood moisture content, temperature, and time of exposure to conditions suitable for the onset, growth, and propagation of mold or rot are critical parameters when assessing the longevity of wood frame structures. A number of approaches for assessing the vulnerability of wood frame structures to deterioration have been developed in recent years; one of which has been used by NRC-Construction for evaluating the performance of wall assemblies based on the results from hygrothermal simulation. In this paper, an example of the use of this approach for the assessment of a stucco-clad wall incorporating drainage cavities is described as is the use of a mold index to capture the risk of the formation of mold in walls. An example is given in assessing the moisture management of a stucco-clad wood frame wall incorporating vented and ventilated drainage cavities for three Canadian locations., Symposium on Advances in Hygrothermal Performance of Building Envelopes: Materials, Systems and Simulations, 26-27 October, 2016, Orlando, FL. USA, Series: Selected Technical Papers; no. STP1599

Field monitorings of thermal performance of residential 2 x 6 wood-frame wall systems that had been retrofitted using vacuum insulation panels (VIPs) and extruded polystyrene foam (XPS) panels were undertaken in May 2011 – May 2012 at the Field Exposure of Walls Facility (FEWF) of NRC-Construction. The main objective of this research was to measure the steady-state and transient thermal performance of three wall assemblies (4 ft x 6 ft), two of which incorporated VIPs within an XPS Tongue and Groove (T&G) configuration and VIPs within an XPS Clip-On (C-O) configuration, and a third assembly incorporating only XPS. The three wall assemblies were installed in the FEWF for 1-year cycle of exposure to outdoor natural weather conditions. The hygIRC-C model was used in this study. The results of the model calculations were in good agreement with the experimental data. Given that the VIPs could be punctured during the installation process or could fail during normal operating conditions, additional model calculations were used to predict the thermal resistance in cases where one or more VIPs failed. The model was also used to predict the yearly cumulative heat losses across these wall systems. It is important to point out that the aging effect and the effect of the thermal bridging due to envelope (i.e. skin) of the VIPs are not accounted for in this study. However, sensitivity analysis of the thickness and thermal conductivity of the VIP envelope was conducted to investigate the effect of these parameters on the effective thermal resistance of VIP.

A table is provided in the 2009 ASHRAE Handbook of Fundamentals (Chapter 26) that contains the thermal resistances (R-values) of enclosed airspaces. The ASHRAE table provides the R-values for enclosed airspaces of different thicknesses, effective emittances, mean airspace temperatures, and temperature differences across the airspaces. This table is extensively used by modelers, architects and building designers in the design for the R-values of building enclosures. The effect of the airspace aspect ratio (length/thickness) on the R-value is not accounted for in the ASHRAE table. However, previous studies showed that the aspect ratio of the airspace can affect its R-value. In this paper, the previous studies that focused on determining the R-values for vertical enclosed airspaces and horizontal enclosed airspaces with upward and downward heat flow are extended to investigate the effect of the aspect ratio on the R-values of 45° sloped enclosed airspaces under downward heat flow for different airspace thicknesses and having a wide range of values for the effective emittance, mean temperature, and temperature differences across the airspaces. The predicted R-values are compared with those provided in the ASHRAE table. Considerations are also given to investigate the potential increase in the R-values of enclosed airspaces when a thin sheet is placed in the middle of the airspace and whose surfaces have different values of emissivity. Thereafter, practical correlation is developed for determining the R-values of 45° sloped enclosed airspaces for future use by modelers, architects and building designers. The simplicity of this correlation for the sloped enclosed airspaces along with those that were previously developed for vertical and horizontal airspaces suggests that these correlations could be included in the ASHRAE Handbook of Fundamentals.

The thermal resistance ( R -value) of an enclosed airspace depends on the emissivity of all surfaces that bound the airspace, the size and orientation of the airspace, the direction of heat transfer through the airspace, and the respective temperatures of all surfaces that define the airspace. A table is provided in the 2009 ASHRAE Handbook of Fundamentals (Chapter 26) that contains the R -values of enclosed airspaces. The ASHRAE table is extensively used by modellers, architects and building designers in the design for thermal resistance of building enclosures. This table provides R -values for enclosed airspaces for different values of airspace thickness, effective emittance, mean airspace temperature, and temperature differences across the airspace. The effect of the airspace aspect ratio (length/thickness) on the R-value is not accounted for in the ASHRAE table. However, in previous studies, it was shown that the aspect ratio of the airspace can affect its R-value. In this paper, previous studies undertaken by the author that focused on determining the R -value for vertical enclosed airspaces and horizontal enclosed airspaces with downward heat flow are extended to investigate the effect of the aspect ratio on the R -value of horizontal enclosed airspaces under an upward heat flow condition for different airspace thicknesses and having a wide range of values for effective emittance, mean temperature, and temperature differences across the horizontal airspaces. The R -values predicted from numerical simulation are compared with those provided in the ASHRAE table. Considerations were also given to investigate the potential increase in the R -values of enclosed airspaces when a thin sheet is placed horizontally in the middle of the airspace and whose surfaces have different values of emissivity. Thereafter, practical correlations are developed for determining the R -values of horizontal enclosed airspaces for future use by modellers, architects and building designers. The simplicity of these correlations for horizontal airspaces with upward heat flow along with those that were previously developed for vertical airspaces and horizontal airspaces with downward heat flow suggests that these correlations could be included in the ASHRAE Handbook of Fundamentals.

Reflective insulations are being used in home attics, flat roofs, sloped roofs and wall systems of building envelopes. The present model, hygIRC-C, was used to investigate the contribution of the reflective insulations to the thermal resistance of specimens. The predictions of the present model were compared with test data of different sample stacks with different types of reflective insulations. In a previous study, the present model was benchmarked using test data obtained from a Guarded Hot Box (GHB) in accordance with the ASTM C-1363 test method. In this study, the test data was obtained from a different test method based on the heat flow meter in accordance of ASTM C-518 in the case of horizontal sample stacks with reflective insulations. Results showed that the predicted heat fluxes on the same area and same location of Heat Flux Transducers (HFTs) on the top and bottom surfaces of the sample stacks are in good agreement with the measured heat fluxes (within ±1%). The derived R-values using these heat fluxes are also in good agreements. Due to the combined effect of heat transfer by convection and radiation in the airspace (facing the reflective surface), these predicted and measured heat fluxes are greater than the area-weighted average heat flux of whole sample stack, which is needed to determine the effective R-value of the sample. As such, the derived R-value from the test data resulted in underestimation of the effective R-value of the sample stack. After gaining confidence in the present model, it was used to conduct parametric study in order to quantify the contribution of reflective insulations to the effective R-value for a sample stack with different inclination angles, different directions of heat flow (upward and downward) and for a wide range of foil emissivity. Furthermore, the present model was used to compare the predicted R-values with the listed R-values in the 2009 ASHRAE Handbook [22] for enclosed air cavity (20 mm thick) of different effective emittance, inclinations and directions of heat flow.

A Wall Energy Rating (WER) system has been proposed to account for simultaneous thermal conduction and air leakage heat losses through a full-scale insulated wall system. Determining WER requires performing two standard tests on a full-scale wall specimen: a thermal resistance test and an air leakage test. A 3D model representation of the wall specimen is developed to combine the results of these tests to obtain an accurate prediction of the wall thermal resistance (apparent R-value) under the influence of air leakage. Two types of wall configurations were tested and simulated. The first one was a standard 2? by 6? wood stud frame construction, made of spruce, spaced at 16? (406 mm) o/c in 2.4 m x 2.4 m full-scale wall specimens. The second wall configuration was similar to the first one except that it included through-wall penetrations. The cavities of the two types of wall configurations were filled with different types of insulation, namely: glass fibre batts and two different types of open cell spray polyurethane foams (light density, 6.8 and 12 kg/m3 nominal), a total of six walls.

A 3D numerical model was developed to investigate the effect of foil emissivity on the effective thermal resistance of an above-grade wall assembly with foil bonded to wood fibreboard in a furred assembly having airspace next to the foil. This model solved simultaneously the energy equation in the various material layers, the surface-to-surface radiation equation in the furred airspace assembly, Navier–Stokes equation for the airspace, and Darcy and the Brinkman equations for the porous material layers. In this work, the furring was installed horizontally. In the first phase, the present model was benchmarked against the experimental data generated by a commercial laboratory for an above-grade wall assembly. The wall consists of a conventional wood frame structure sheathed with fibreboard and covered on the interior side with a low emissivity material bonded to wood fibreboard that is adjacent to a furred airspace assembly. The results showed that the predicted R -value was in good agreement with the measured one. After gaining confidence in the present model, it was used to predict the effective thermal resistance of the same above-mentioned wall but having Oriented Strand Board (OSB) sheathing in lieu of wood fibreboard sheathing. In the second phase, the model was used to quantify the contribution on the wall R -value by having a low foil emissivity. The results showed that a low foil emissivity of 0.04 can increase the R -value of this wall to as much as ∼9%. This is on-going research. The present model is being used to investigate the transient thermal response of foundation wall systems with furring installed horizontally and vertically, and subjected to different Canadian climate conditions.

Thermal analysis is performed of radioisotope power systems (RPSs) in which skutterudite based thermoelectric arrays (SKTAs) of 2 × 7 and 4 × 7 unicouples are thermally coupled to general purpose heat sources (GPHSs). The SKTAs are separated from the GPHS bricks by a thin graphite sleeve to ensure a hot junction temperature of 973 K and minimal or no increase in the 238 PuO 2 fuel temperature. They are connected electrically in series, and the performance parameters of the RPSs are calculated as functions of load voltage from 24 to 38 VDC. The cold junction temperature of the SKTAs and the radiator base temperature are determined from coupling the unicouples performance optimization model and the radiator thermal analysis model for sizing the aluminum fins. Calculated peak specific powers of the RPSs at the beginning of mission (BOM) are compared with those calculated at the peak electric power at different load voltages. The load voltage strongly affects the performance of the RPSs. The peak specific powers and those corresponding to the peak electrical powers increase with increasing load voltage up to certain values then drop with further increase in load voltage. The highest BOM specific powers of ∼6.859–6.973 W e /kg, are ∼43.3–45.7% higher than that of the heritage RTG (4.786 W e /kg) with 7 GPHS bricks and SiGe unicouples. Such specific powers for the RPSs with SKTAs are attainable with 28.6% less 238 PuO 2 fuel and at 2.85–11.62% more BOM electrical power (122 W e ) than those of the heritage RTG (105 W e ).

Advanced radioisotope power systems (ARPSs) for future planetary missions require higher conversion efficiency than the state-of-the-art (SOA) SiGe thermoelectric converter in order to decrease system mass and reduce mission cost. The performance of three cascaded thermoelectric converters (CTCs) for potential use in ARPSs is investigated at heat rejection temperatures of 375, 475 and 575 K and input thermal powers of 1, 2 and 3 Wth. These CTCs have top SiGe unicouples that are thermally, but not electrically, coupled to bottom unicouples having one of the following compositions: (a) TAGS-85 (p-leg) and 2N–PbTe (n-leg); (b) CeFe3.5Co0.5Sb12 (p-leg) and CoSb3 (n-leg); and (c) segmented p-leg of CeFe3.5Co0.5Sb12 and Zn4Sb3 and n-leg of CoSb3. The top and bottom unicouples in the CTCs are of the same length (10 mm), but the optimized cross-sectional areas of the n- and p-legs for maximum efficiency are different. The nominal hot junction temperature of the top SiGe unicouples at their peak efficiencies is 1273 K and that of the cold junction is 780 K when the bottom unicouple is of composition (a) and 980 K for compositions (b) and (c). The hot junction temperatures of the bottom unicouples are taken 20 K lower than the cold junctions of the top unicouples, but the input thermal powers to the former are the same as those rejected by the latter. Assuming zero side heat losses and a contact resistance of 150 μΩ cm2 per leg in the top and bottom unicouples, the calculated peak efficiencies of the CTCs vary from 9.43% to 14.35%. These efficiencies are 40–113% higher, respectively, than that of SOA SiGe (∼6.5%) when operating at the cold junction temperature of 566 K and the same hot junction temperature (1273 K) and contact resistance per leg. Decreasing this resistance to a realistic value of 50 μΩ cm2 per leg increases the peak efficiencies of the CTCs by 0.5–0.9 percentage points to 9.93–15.25%.

The breakup of a thin non-evaporating liquid film that is either flowing down or climbing on a vertical or inclined surface and subject to cocurrent or countercurrent interfacial shear (or gas flow) is investigated analytically. Analytical expressions for the dimensionless liquid film thickness, Δ min , and wetting rate, Γ min , at breakup are derived based on the minimization of the total energy of a stable rivulet, formed following the film breakup

High efficiency segmented thermoelectric unicouples (STUs) made of n-type Bi2Te3 and CoSb3 based alloys and p-type Bi2Te3 and CeFe4Sb12 based alloys have recently been developed at the Jet Propulsion Laboratory (JPL). A 1-D analytical model of STUs, which assumes zero side heat losses, is developed and its predictions are compared with some results of experiments performed at JPL to measure the performance parameters of two STUs, uni8 and uni12. Calculations of the effects of contact resistance and side heat losses on the performance of these STUs are presented and discussed. The results indicate that had uni8 and uni12 been well insulated and the contact resistance per leg ∼50 μΩ cm2, they could have achieved a conversion efficiency of ∼12%, in the tests performed at Tc=305–316 K and Th=872–885 K. However, the actual contact resistances of ∼146 and 690 μΩ cm2 per leg and the side heat losses of 3.7 and 1.83 W, for uni8 and uni12, respectively, limited the peak conversion efficiency in the tests to ∼5.5% and 4.6%, respectively. Calculations indicated that STUs having a total contact resistance ∼50 μΩ cm2 per leg and being well insulated on the sides could potentially achieve a peak conversion efficiency of 15% when operated between 973 and 300 K.

The 2009 ASHRAE Handbook - Fundamentals (Chapter 26) provided a table that contains the thermal resistances (R-values) of vertical, horizontal, and high-sloped (45°) enclosed airspaces. This table is extensively used by modelers, architects, and building designers in the design for the R-values of building enclosures. The effect of the airspace aspect ratio and the inclination angle (θ) of 30° on the R-values are not accounted for in the ASHRAE table. However, previous studies showed that the aspect ratio of the airspace can affect its R-value. In this article, the previous studies that focused on determining the R-values for vertical, horizontal, and high-sloped enclosed airspaces are extended to investigate the effect of the aspect ratio on the R-values of low-sloped (θ = 30°) enclosed airspaces under downward heat flow for different airspace thicknesses and having a wide range of values for the effective emittance, mean temperature, and temperature differences across the airspaces. Thereafter, practical correlation is developed for determining the R-values of low-sloped enclosed airspaces for future use by modelers, architects, and building designers.

Many parts of the building envelope contain enclosed airspaces. The thermal resistance (R-value) of an enclosed airspace depends on the emissivity of all surfaces that bound the airspace, the size and orientation of the airspace, the direction of heat transfer through the airspace, and the respective temperatures of all surfaces that define the airspace. The 2009 ASHRAE Handbook of Fundamentals (Chapter 26) provides a table that contains the R-values for an enclosed airspace. The ASHRAE table is extensively used by modelers, architects and building designers in the design of building enclosures. This table provides R-values for enclosed airspaces for different values of the thickness of the airspace, effective emittance, mean airspace temperature, and temperature differences across the airspace. The effect of the airspace aspect ratio (height/thickness of airspace) on the R-value is not included in the ASHRAE table. However, in a recent study on the R-value of reflective insulations using a numerical simulation model, it was shown that the aspect ratio of the airspace can affect the R-value of the enclosed airspace. The numerical simulation model used in this study had been benchmarked against experimental data obtained using two standard test methods: ASTM C-518 and ASTM C-1363. In this paper, a numerical simulation study was conducted, that was based on previous work focused on enclosed airspaces, to investigate the effect of the aspect ratio on the R-value of vertical enclosed airspaces of different thicknesses and having a wide range of values for effective emittance, mean temperature, and temperature differences across the airspace. The R-values predicted from numerical simulation are compared with those provided in the ASHRAE table. Considerations were also given to investigating the potential increase in R-values of enclosed airspaces when a thin sheet is placed vertically in the middle of the airspace and whose surfaces have different values of emissivity. Finally, practical correlations are developed for determining the R-values of an enclosed airspace for future use by modelers, architects and building designers. The simplicity of these correlations suggests that these could be included in the ASHRAE Handbook of Fundamentals.

The 2009 ASHRAE Handbook of Fundamentals (Chapter 26) provides a table that contains the thermal resistances (R-values) of enclosed airspaces for different values of airspace thickness, effective emittance, mean airspace temperature, and temperature differences across the airspace. This table is extensively used by modelers, architects, and building designers in the design for thermal resistance of building enclosures. The effect of the airspace aspect ratio (length/thickness) on the R-value is not accounted for in the ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) table. However, in previous studies, it was shown that the aspect ratio of the airspace can affect its R-value. In this article, the previous studies by the author who focused on determining the R-value for vertical enclosed airspaces and horizontal enclosed airspace under upward heat flow condition are extended to investigate the effect of the aspect ratio on the R-value of horizontal enclosed airspaces under a downward heat flow condition for different airspace thicknesses and having a wide range of values for effective emittance, mean temperature, and temperature differences across the airspaces. The R-values predicted from numerical simulation are compared with those provided in the ASHRAE table. Considerations were also given to investigate the potential increase in the R-values of enclosed airspaces when a thin sheet is placed horizontally in the middle of the airspace and whose surfaces have different values of emissivity. Thereafter, practical correlation was developed for determining the R-values of horizontal enclosed airspaces for future use by modelers, architects, and building designers. The simplicity of this correlation derived for horizontal airspaces under downward heat flow condition together with those that were previously developed for vertical airspaces and horizontal airspaces under upward heat flow condition suggests that these correlations could be included in the ASHRAE Handbook of Fundamentals.

The minimum total energy (MTE) criteria for determining the minimum wetting rate and the minimum thickness of an isothermal, thin liquid film flowing down a vertical adiabatic surface are examined. An analytical expression of the profile of a stable liquid rivulet and of the two-dimensional velocity distribution in the rivulet developed using the Ritz method are incorporated into the MTE criterion to improve its predictions of the minimum wetting rate (MWR) and the corresponding minimum liquid film thickness (MLFT). The present predictions of the MWR and MLFT are in good agreement, to within ±10–20%, with experimental data for water and glycerol–water mixtures and with the values calculated from the MWR measurements, respectively. The accuracy of the present predictions is demonstrated for three conditions, namely: (a) incipient breakup of liquid film, (b) formation of a stable dry patch, and (c) rewetting of a dry surface. For the latter the advancing contact angle is substituted for the equilibrium contact angle in the developed analytical expressions for the MLFT and corresponding MWR.

When solar radiation hits a roof surface, a part of solar energy is reflected and part is absorbed. The absorbed part of solar energy results in an increase of the surface temperature of the roof. Cool reflective (white) roofs use bright surfaces to reflect a significant portion of the incident short-wave solar radiation, which lowers the surface temperature compared to conventional (black) roofs with bituminous membrane. As such, white roofs help reduce the urban heat island effect during the summer. The question is “do white roofs lead to moisture-related problems in northern and southern climates?” To help answer this question, numerical simulations were conducted to compare the hygrothermal performance of a single kind of white and black roofs under different outdoor and indoor conditions. The outdoor conditions are obtained from the weather database of the National Research Council of Canada, Institute for Research in Construction (NRC–IRC). The indoor conditions are taken based on the European standard (EN 15026) and ASHRAE recommendations for conditioned space. The type of roofs considered in this study is Modified-Bitumen (MOD-BIT) roofing systems. The numerical simulations were conducted for the outdoor climate of Toronto (ON), Montreal (QC), St John’s (NL), Saskatoon (SK), Seattle (WA), Wilmington (NC) and Phoenix (AZ). Results showed that for the outdoor climates of St John’s and Saskatoon, the white roofs could lead to longer-term moisture-related problems. However, for the outdoor climates of Toronto, Montreal, Seattle, Wilmington and Phoenix, buildings with white roofs were shown to have a low risk of experiencing moisture damage. Also, buildings with white roofs in these locations were predicted to show a net yearly energy savings compared to buildings with black roofs.

In order to evaluate the effectiveness of in-place emergency ventilation strategies to control smoke spread in the event of a fire in a section of a roadway tunnel, both numerical and experimental studies were performed. The experimental study was conducted to provide the necessary initial and boundary conditions for the numerical phase of the investigation. A fire heat release rate of 1 MW was used in all fire tests. This fire heat release rate was selected to minimize the risk of damage to the tunnel and its associated systems while producing reliable data for visualizing the smoke movement in the tunnel. The numerical study used Computational Fluid Dynamics, Fire Dynamic Simulator version 4.0 to investigate smoke removal in the tunnel for large fire of 30 MW (bus or truck on fire). In total, four field fire tests and seven numerical simulations were conducted. Based on the study results, recommendations were made to optimize the ventilation scenarios in the tunnel section. This article presents the details of the study as well as the recommendations made.

This paper presents the results of a survey of floor areas and combustible contents in multi-family dwellings such as semi-detached houses, town houses and low-rise apartments. The survey was primarily based on measurements and photographic information obtained from real-estate websites. This is a novel method, which reduces the effort required to conduct fire load surveys in residential buildings. In addition to quantifying combustible contents, an important objective of the survey was to determine the similarities in combustible contents and configurations of these dwellings, which could be used in designing fire experiments. The survey provided an insight into the types and quantity of combustible contents found in the dwellings, as well as the types of floor configurations and other information that are pertinent to fire issues. Typical furnishings that constituted a significant portion of the movable fire load were identified and possible values of fire load densities were calculated for rooms such as: kitchens, dining rooms, living rooms and bedrooms. The average fire load densities in various rooms were estimated to be: kitchens—807 MJ/m2; dining rooms—393 MJ/m2; living rooms—412 MJ/m2; basement living rooms—288 MJ/m2; primary bedrooms—534 MJ/m2; and, secondary bedrooms—594 MJ/m2. Although kitchens had the highest fire load densities the actual fire load (heat content) was found to be lower than bedrooms, which have a higher fire load due to the presence of mattresses, clothing and carpeting.

The performance and specific electrical powers of Radioisotope Power Systems (RPSs) with Skutterudite‐based Thermoelectric Arrays (SKTAs) of 2×7 and 4×7 unicouples connected electrically in series are calculated as functions of load voltage from 24 to 38 VDC. The p‐legs of the unicouples are made of CeFe3.5Co0.5Sb12 and the n‐legs are made of CoSb3, and the optimized cross‐section areas of these legs for maximum efficiency operation are calculated as functions of the RPS terminal voltage. The RPS employs five General Purpose Heat Source (GPHS) bricks, generating 1250 Wth at BOM, and 40 SKTAs, which are connected in series in two or four parallel strings. The peak electrical power and peak conversion efficiency of the SKTAs (20 mm long) occurs at the same electrical current because the unicouples operate at constant hot junction temperature (973 K) and constant input thermal power. The cold junction temperature of the unicouples and the radiator base temperature are determined from coupling the unicouples performance optimization model with a detailed radiation thermal analysis for sizing the aluminum fins for rejecting waste heat into space. The calculated peak specific powers and the corresponding electrical powers of the RPSs at Beginning‐Of Mission (BOM) are compared with those calculated at the peak electric power at different load voltages. Results indicated that the value of the load voltage strongly affects the performance of the RPS. Both the RPS peak specific powers and those corresponding to the peak conversion efficiency / peak electrical power increase with increasing the load voltage up to certain values then drop with further increasing that voltage. The highest BOM specific powers of the RPS is ∼ 6.859 –6.973 We/kg, ∼ 43.3% and 45.7% higher than that of the RTG (4.786 We/kg) with 7 GPHS brick and SiGe unicouples. Such specific electrical powers of the RPS with SKTAs are attainable with 28.6% less 238PuO2 fuel and 2.85% to 11.62% more BOM electrical power (122 We) than the RTG (105 We).

This paper presents results of three performance tests of Skutterudites and Segmented Thermoelectric (STE) unicouples performed at average hot and cold shoe temperatures of ∼ 973 K and 300 K, respectively, to verify theoretical predictions. The first two tests (MAR‐03 and JUN‐03) involved non‐segmented Skutterudites unicouples of slightly different dimension but same materials for the n‐ (CoSb3) and p‐ (CeFe3.5Co0.5Sb12) legs. The test duration is 450 hours for MAR‐03 and 1200 hours for JUN‐03. The third test (JUL‐03) is for a Skutterudites/Segmented (STE) unicouple, in which the p‐leg has two segments of CeFe3.5Co0.5Sb12 and Bi0.4Sb1.6Te3 and the n‐leg has two segments of CoSb3 and Bi2Te2.95Se0.05. The segments in the n‐ and p‐legs have different lengths and cross‐sectional areas. The JUL‐03 test duration is 645 hours. All tested unicouples are fabricated at JPL and assembled and tested in the vacuum facility at the University of New Mexico in argon at ∼ 0.051 to 0.068 MPa to suppress the sublimation of antimony from the legs near the hot shoe. Detailed measurements of the open circuit voltage, voltage across the n‐ and p‐legs, the voltage‐current (V‐I) characteristics, and the hot and cold shoe temperatures are performed in all tests. In JUL‐03, additional measurements of the interfacial temperatures and the voltage across the segments in the n‐ and p‐legs are obtained as functions of test duration. Estimates of beginning‐of‐life (BOL) conversion efficiencies of 10.7% for Shutterudites and 13.5% for STE unicouples are within 10% of theoretical predictions assuming zero side heat losses and zero contact resistances. Estimates of these losses in the tests are 2.3 W in MAR‐03 to 9.3 W in JUL‐03, thus actual efficiencies in the tests are ∼ 40–50% lower. Because cross sectional areas of the legs of JUL‐03 are much larger than of both MAR‐03 and JUN‐03, the measured BOL peak electrical power per unicouple is 1.295 We versus 0.671 We for the latter.

Conceptual designs of Advanced Radioisotope Power System (ARPS) with Cascaded Thermoelectric Converters (CTCs) are developed and optimized for maximum efficiency operation for End‐Of Mission (EOM) electrical power of at least 100 We. These power systems each employs four General Purpose Heat Source (GPHS) bricks generating 1000 Wth at Beginning‐of‐Life (BOL) and 32 Cascaded Thermoelectric Modules (CTMs). Each CTM consists of a top and a bottom array of thermoelectric unicouples, which are thermally, but not electrically, coupled. The top and bottom arrays of the CTMs are connected electrically in series in two parallel strings with the same nominal voltage of > 28 VDC. The SiGe unicouples in the top array of the CTMs are optimized for nominal hot shoe temperature of 1273 K and constant cold shoe temperature of either 780 K or 980 K, depending on the thermoelectric materials of the unicouples in the bottom array. For a SiGe cold junction temperature of 780 K, the unicouples in the bottom array have p‐legs ...

An important consideration in the design and optimization of segmented thermoelectric (STE) converters is determining the relative lengths and the interfacial temperatures of the segments of the different materials in the nand p-legs. These variables are determined using a genetic algorithm in conjunction with one-dimensional analytical model of STE converters. Results indicated that when maximizing the efficiency, the interfacial temperatures between various segments are close to those at the intersections of the ZT curves of the thermoelectric materials of the adjacent segments. When maximizing electrical power density, however, the interfacial temperatures are different from those at the intersections of the ZT curves, but close to the temperatures at the intersections the characteristic power, CP, curves of the thermoelectric materials of the segments. The CP = T/sup 2/Zk, appears explicitly in the expression for the maximum power density and has the unit of W/m. Results also showed that the number of the segments in the n- and p-legs of the converters optimized for maximum power density are generally fewer than when the same converters are optimized for maximum efficiency.

This paper presents a one-dimensional, optimization model of Segmented Thermoelectric Unicouples (STUs). The model predictions are compared with some results of experiments performed at the Jet Propulsion Laboratory to measure the performance parameters of a number of STUs made of n-type Bi2Te3 and CoSb3 based alloys and p-type Bi2Te3 and CeFe4Sb12 based alloys. In addition to determining the input and rejected thermal power of the STUs and the axial temperature distributions in the n- and p-legs, the present model optimizes the lengths and/or the interfacial temperatures of the various segments for either optimum conversion efficiency or optimum electrical power density. Results indicate that well-insulated STUs could have a conversion efficiency of ∼12%, when operated at Tc=305–316 K and Th=872–885 K and the total interfacial resistance per leg is ∼50 μΩ-cm2. However, due to the high total interfacial resistances of ∼690 and 146 μΩ-cm2 and the side heat losses of 1.83 W and 3.7 W, respectively, in the experiments, the peak conversion efficiency is ∼5.5% and 4.6% for uni8 and uni12, respectively. Model predictions show that, for a total interfacial resistance of ∼50 μΩ-cm2 per leg and zero side heat losses, skutterudite STUs have the potential of achieving a conversion efficiency of 15% when operated at hot and cold side temperatures of 973 K and 300 K, respectively.

For the past 25 years, unicouples made of Silicon Germanium alloys (Si0.8Ge0.2 and Si0.63Ge0.38) have been used in the majority of the spacecraft powered by Radioisotope Thermoelectric Generators (RTGs) to explore various planets of the solar system as well as the sun. These unicouples operate typically at hot and cold side temperatures of 1175–1273 K and 573 K, respectively, converting the heat produced in the General Purpose Heat Source (GPHS) modules to electricity at efficiencies

(Egyptian Journal of Medical Laboratory Sciences: 2001: 10(1): 65-70)

14152 Background: Since 2001, 5 tyrosine kinase inhibitors (TKi’s; imatinib, erlotinib, sorafenib, sunitinib and dasatinib) have been approved for hematologic and solid tumor indications including, CML, ALL, GIST, RCC, pancreatic and NSCLC. While individual agents are designed to inhibit the TK activity of specific targets, “cross-talk” with non-target TKs (e.g., ABL, EGFR, VEGFRs, KIT, KDR, CSF1R, PDGFRs, RET, the SRC family, EPHA2, RAF, and FLT3) is extensive. The relationship between inhibition of individual kinases and the toxicity profile of each drug is unclear. Methods: Following from the observation of cardiovascular (CV) toxicity in clinical settings (pre- and post- marketing) and from the original non-clinical toxicologic evaluations, a new “class-related” review of non-clinical toxicological findings was conducted. To compare the non-clinical and clinical CV findings, the Adverse Event Reporting System (AERS) was searched for all events, excluding those of non-CV nature and those unlikely to be drug-related (e.g. hemorrhagic events were excluded from the initial analyses). Individual patient reports were not reviewed in full, therefore definitive attribution of disease related events can not be made. Results: While variable in expression, the non-clinical signs of toxicity included cardiac and vascular inflammation, cardiac degeneration and hypertrophy, decreased cardiac function (e.g. LVEF decreases), alterations in blood pressure, and QT prolongation. Clinical reports for the TKi’s have included hypo- and hypertension, conduction abnormalities and arrhythmias, cardiac hypertrophy and changes in cardiac function (LVEF and CHF). Conclusions: It is not possible at this time to relate the CV toxicities associated with the TKi’s to a specific pattern of TK inhibition. CV toxicity has been observed both clinically and non-clinically and warrants further investigation. No significant financial relationships to disclose.

3173 Small businesses normally do not have a complete range of expertise and resources necessary to bring products to market from initial discovery through the expensive development phases. The NCI...

A number of fire ventilation scenarios were investigated in order to identify the proper ventilation scheme for conducting design fire tests in a medium-sized residential room of a size of 4.2 m long, 3.8 m wide and 2.4 m high. The ventilation schemes were based on using a window, door, or both with different sizes. The fuel package that was used in all scenarios consisted of a mock-up sofa made of polyurethane foam and two wood cribs underneath it. The selection of this fuel package is supported by fire statistics that many fatal residential fires begin with an item of upholstered furniture. The CFD technique was used to conduct the numerical simulations for eleven ventilation scenarios using the Fire Dynamics Simulator (FDS) version 5. The effect of window and door sizes, and fire load location on the heat release rate, burning rate, temperature during the period of fully-developed fire (post-flashover), and the onset of post-flashover and its duration were investigated.Copyright © 2008 by ASME

This paper presents the results of a 3‐D performance analysis of Skutterudite‐Based Segmented Unicouple (SKU) with nine μm thick Molybdenum (Mo) coatings on n‐ and p‐legs near the hot junction. The analysis performed at hot and cold junction temperatures of 973 K and 300 K investigated the effect of the coating on lateral distributions of the electric current, voltage, and temperatures in the legs and the conversion efficiency and electric power generated by the unicouple. The p‐ and n‐legs are 20 mm long and have hot and cold segments of CeFe3.5Co0.5Sb12 and Bi0.4Sb1.6Te3, and of CoSb3 and Bi2Te2.95Se0.05, respectively. The cross‐section area of the p‐leg is 11 mm2. The cross sectional area of the n‐leg and the lengths of the Mo coatings and of various segments of the legs are determined for maximum conversion efficiency using a 1‐D optimization model. The 3‐D analysis performed with ANSYS finite element commercial software used the dimension determined by the 1‐D model. Results show that the electric currents near the outer surface of the Mo coatings flow in the opposite direction to those in the n‐ and p‐legs. In very thin parts of legs near the interface with the coatings, electric currents flow in the same direction as in the coatings, but decrease rapidly with inward distance from the interface, eventually becoming zero, then flowing in the same direction as the electric current in the legs. Such current circulation increases joules losses in the coated parts of the hot segments of the legs, decreasing the conversion efficiency. The increased heat flow from the hot shoe through the metallic coatings contributes to decreasing the conversion efficiency, but increasing the electric power generated by SKU.

Three Cascaded Thermoelectric Converters (CTCs) are optimized for potential use in Multi‐Mission Advanced Radioisotope Power Systems (MM‐ARPS) for electrical powers up to 1 kWe, or even higher, in support of 7–10 year missions. The peak efficiencies of these CTCs of 9.43% to 14.32% are 40% to 110% higher than that of SiGe in State‐of‐the‐Art (SOA) Radioisotope Thermoelectric Generators (RTGs). Such high efficiencies would significantly reduce the amount of 238PuO2 fuel and the total system mass for a lower mission cost. Each CTC is comprised of a SiGe top unicouple that is thermally, but not electrically, coupled to a bottom unicouple with one of the following three choices of thermoelectric materials: (a) p‐leg of TAGS‐85 and n‐leg of 2N‐PbTe; (b) p‐leg of CeFe3.5Co0.5Sb12 and n‐leg of CoSb3; and (c) segmented p‐leg of CeFe3.5Co0.5Sb12 and Zn4Sb3 and n‐leg of CoSb3. The length of the top and bottom unicouples is 10 mm, but the cross‐sectional areas of the n‐ and p‐legs of the unicouples are optimized for...

A performance test of a Skutterudite‐based unicouple (MAY‐04) with a metallic coating to suppress the sublimation of antimony from the legs near the hot junction is performed in vacuum (∼ 9 ×10−7 torr) for ∼ 2,000 hours at hot and cold junction temperatures of 892.1 ± 11.9 K and 316.1 ± 5.5 K, respectively. The p‐leg is made of CeFe3.5Co0.5Sb12 and the n‐leg is made of CoSb3. Presented are the measured voltage‐current characteristics, electrical power, open‐circuit voltage, and the Seebeck coefficients of the legs as functions of cumulative test time. Also presented is the estimate of the conversion efficiency, ∼ 96 hrs after the start of test. To demonstrate the effectiveness of the metallic coating, the measurements for MAY‐04 are compared with those of two uncoated unicouples of the same leg materials (MAR‐03 and JUN‐03), which had been tested earlier. The cross‐sectional areas of the legs in MAY‐04 are larger than those in MAR‐03 and JUN‐03, tested in argon cover gas at ∼ 0.051–0.068 MPa for 450 and 1...

Intr Anoxic brain insult is a sequalae of tissue hypoperfusion during cardiac arrest that may lead to varieties of neurological outcome in patients [1].One of the main drawbacks in the diagnosis of brain injury post-cardiac arrest is the absence of a widely available and rapid diagnostic test. pNFH might be an ideal biomarker for brain injury as it is axon specific [2],highly immunogenic [3] and an excellent target for antibody-based assays [4].