CFD modeling and performance evaluation of multipass solar air heaters

This article investigates the impacts of flow configurations on the thermal performance of a solar heater system. Recycled aluminum cans (RACs) have been utilized as turbulators with a double pass single duct solar air collector. The CFD software of COMSOL Multiphysics V5.3a is used to model three designs: Cocurrent (model A), countercurrent (model B), and U-shape (model C). The numerical results reveal that the U-shape design offers a greater thermal performance of 5.4% and 6.5%, respectively, compared with the cocurrent and countercurrent flow models. Furthermore, an outdoor experiment is performed based on the numerical modeling of flow configurations. The experimental setup is examined for three configurations of model C, namely, solar air heater (SAH) without RAC model C-I (plain model), SAH with in-line RAC layout (model C-II), and SAH with staggered RAC layout (model C-III). We found the double pass single duct solar air collector (model C) design is in a good agreement with the experimental data, and model C-III has a better thermal efficiency of 60.2%, compared to those of model C-II, 53.1%, and model C-I, 49.4%

Modelling and simulation of a novel Electrical Energy Storage (EES) Receiver for Solar Parabolic Trough Collector (PTC) power plants

In this paper, the mathematical modelling of a novel Electrical Energy Storage (EES) Receiver for Solar Parabolic Trough Collector (PTC) is presented. The EES receiver is essentially a Heat Collecting Element (HCE) with built in storage in the form of thermal batteries such as the Sodium Sulphur (NaS) battery. The conceptual design and mathematical models describing the operation of the receiver are presented along with important results of model validation. When held under adiabatic conditions (a primary indicator of model validity), results were highly consistent with established PTC, models and with National Renewable Energy Laboratory (NREL, USA) experimental data for existing SCHOTT PTR-70 and Solel UVAC3 receiver tubes, currently being used in existing PTC power plants

Do pilocarpine drops help dry mouth in palliative care patients: A protocol for an aggregated series of n-of-1 trials

Background: It is estimated that 39,000 Australians die from malignant disease yearly. Of these, 60% to 88% of advanced cancer patients suffer xerostomia, the subjective feeling of mouth dryness. Xerostomia has significant physical, social and psychological consequences which compromise function and quality of life. Pilocarpine is one treatment for xerostomia. Most studies have shown some variation in individual response to pilocarpine, in terms of dose used, and timing and extent of response.We will determine a population estimate of the efficacy of pilocarpine drops (6 mg) three times daily compared to placebo in relieving dry mouth in palliative care (PC) patients. A secondary aim is to assess individual patients' response to pilocarpine and provide reports detailing individual response to patients and their treating clinician. Methods/Design. Aggregated n-of-1 trials (3 cycle, double blind, placebo-controlled crossover trials using standardized measures of effect). Individual trials will identify which patients respond to the medication. To produce a population estimate of a treatment effect, the results of all cycles will be aggregated. Discussion. Managing dry mouth with treatment supported by the best possible evidence will improve functional status of patients, and improve quality of life for patients and carers. Using n-of-1 trials will accelerate the rate of accumulation of high-grade evidence to support clinical therapies used in PC. Trial registration. Australia and New Zealand Clinical Trial Registry Number: 12610000840088. © 2013 Nikles et al.; licensee BioMed Central Ltd

Relationship between temporomandibular joint dynamics and mouthguards: feasibility of a test method

A test system was developed establishing the feasibility of collecting biomechanical data as they relate to the use of mouthguards. Previous experimental studies have examined the physical and mechanical properties of mouthguard materials. This information has been used as a guide for establishing material standards and specifications for the fabrication of mouthguards, but it lacks the key biomechanical parameters required for a thorough mouthguard evaluation. The current study was designed to assess whether the impact force, condylar deflection, and strain superior to the temporomandibular joint region could be measured. A drop test was conducted on a cadaveric specimen to simulate loading at the chin point. To measure the force of impact, an accelerometer was attached to an impactor of known mass. High-speed biplanar (1000 frames per second) radiographs were used to determine condylar displacement. Radio-opaque markers were inserted into the bone at predetermined locations. Total displacement of these markers was determined in reference to anatomical landmarks. Strain gauges were attached to the mandible and skull to monitor the effects of the condyle impacting the base of the skull. Based on the data collected, forces were calculated by determining the product of the time-based acceleration and known mass. A measurable change in force between the mouthguards and the control (no mouthguard) was demonstrated. The average condylar displacement was successfully measured and indicated as an increase in total deflection for impacts conducted with mouthguards. Quantifiable strain was measured in the region above the mandibular fossa with and without the insertion of a mouthguard at all impact conditions. However, it was determined that additional gauges would provide critical data. Key biomechanical parameters for chin-point impacts were determined in the current study. The technique demonstrated that both displacement within the mandibular fossa and loading of the condyles occur during the impact event. Although the current study established a technique that can be used to examine the relationship between mouthguards and jaw-joint injuries, the role, if any, mouthguards play in the reduction of injuries cannot be established until a thorough analysis is completed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74031/1/j.1600-9657.2004.00213.x.pd

A Database of Wing Diversity in the Hawaiian Drosophila

Background. Within genus Drosophila, the endemic Hawaiian species offer some of the most dramatic examples of morphological and behavioral evolution. The advent of the Drosophila grimshawi genome sequence permits genes of interest to be readily cloned from any of the hundreds of species of Hawaiian Drosophila, offering a powerful comparative approach to defining molecular mechanisms of species evolution. A key step in this process is to survey the Hawaiian flies for characters whose variation can be associated with specific candidate genes. The wings provide an attractive target for such studies: Wings are essentially two dimensional, and genes controlling wing shape, vein specification, pigment production, and pigment pattern evolution have all been identified in Drosophila. Methodology/Principal Findings. We present a photographic database of over 180 mounted, adult wings from 73 species of Hawaiian Drosophila. The image collection, available at FlyBase.org, includes 53 of the 112 known species of picture wing\u27\u27 Drosophila, and several species from each of the other major Hawaiian groups, including the modified mouthparts, modified tarsus, antopocerus, and haleakalae (fungus feeder) groups. Direct image comparisons show that major wing shape changes can occur even between closely related species, and that pigment pattern elements can vary independently of each other. Among the 30 species closest to grimshawi, diverse visual effects are achieved by altering a basic pattern of seven wing spots. Finally, we document major pattern variations within species, which appear to result from reduced diffusion of pigment precursors through the wing blade. Conclusions/Significance. The database highlights the striking variation in size, shape, venation, and pigmentation in Hawaiian Drosophila, despite their generally low levels of DNA sequence divergence. In several independent lineages, highly complex patterns are derived from simple ones. These lineages offer a promising model system to study the evolution of complexity

Desmocollin switching in colorectal cancer

The desmocollins are members of the desmosomal cadherin family of cell–cell adhesion molecules. They are essential constituents of desmosomes, intercellular junctions that play a critical role in the maintenance of tissue integrity in epithelia and cardiac muscle. In humans, three desmocollins (Dsc1, Dsc2 and Dsc3) have been described. The desmocollins exhibit tissue-specific patterns of expression; only Dsc2 is expressed in normal colonic epithelium. We have found switching between desmocollins in sporadic colorectal adenocarcinoma with a reduction in Dsc2 protein (in 8/16 samples analysed by immunohistochemistry) being accompanied by de novo expression of Dsc1 (16/16) and Dsc3 (7/16). Similar results were obtained by western blotting of a further 16 samples. No change was found in Dsc2 mRNA, but de novo expression of Dscs 1 and 3 was accompanied by increased message levels. Loss of Dsc2 (8/19) and de novo expression of Dsc1 (11/19) and Dsc3 (6/19) was also found in colorectal adenocarcinomas on a background of colitis. The data raise the possibility that switching of desmocollins could play an important role in the development of colorectal cancer

A Systematic Review of Online Sex Addiction and Clinical Treatments Using CONSORT Evaluation

Researchers have suggested that the advances of the Internet over the past two decades have gradually eliminated traditional offline methods of obtaining sexual material. Additionally, research on cybersex and/or online sex addictions has increased alongside the development of online technology. The present study extended the findings from Griffiths’ (2012) systematic empirical review of online sex addiction by additionally investigating empirical studies that implemented and/or documented clinical treatments for online sex addiction in adults. A total of nine studies were identified and then each underwent a CONSORT evaluation. The main findings of the present review provide some evidence to suggest that some treatments (both psychological and/or pharmacological) provide positive outcomes among those experiencing difficulties with online sex addiction. Similar to Griffiths’ original review, this study recommends that further research is warranted to establish the efficacy of empirically driven treatments for online sex addiction

Lack of correlation between Ki-67 labelling index and tumor size of anterior pituitary adenomas

AIMS AND BACKGROUND: The Ki-67 is a nuclear antigen detected by the monoclonal antibody MIB-1 and its Labeling Index (LI) is considered a marker of normal and abnormal cell proliferation. Pituitary adenomas are generally well differentiated neoplasms, even if in about one third of cases they are invasive of surrounding tissues. The aim of this study is to evaluate the correlation between Ki-67 labelling index and tumor size of pituitary adenomas extimated by means CT and MRI and confirmed at operation. METHODS: Using the monoclonal antibody MIB-1, we evaluated the expression of Ki-67 in 121 anterior pituitary adenomas consecutively operated on in a 48-month period. RESULTS: In relation to neuroradiological (CT and MRI) and surgically verified tumor size, we identified 24 microadenomas, 27 intrasellar macroadenomas, 34 intra-suprasellar macroadenomas, and 36 intra-supra-parasellar macroadenomas. The adenomas were non-infiltrating (76 cases) and infiltrating (45 cases) adenomas. The wall of the cavernous sinus (CS) was infiltrated in 18 cases. Forty-eight adenomas were non-functioning and 73 functioning. The overall mean ± SD Ki-67 LI was 2.72 ± 2.49% (median 1.6). It was 2.59 ± 1.81 in microadenomas, 2.63 ± 3.45 in intrasellar macroadenomas, 1.91 ± 2.11 in intra-suprasellar macroadenomas, and 3.29 ± 5.45 in intra-supra-parasellar macroadenomas (p = 0.27). It was 3.73 ± 5.13% in infiltrating and 2.03 ± 2.41% in non-infiltrating adenomas (p = 0.02), and 5.61 ± 7.19% in CS-infiltrating versus 2.09 ± 2.37% in CS-non-infiltrating adenomas (p = 0.0005). CONCLUSIONS: Our preliminary results seem to exclude significative correlations between Ki-67 LI and tumor size of anterior pituitary adenomas, even if this index can be considered a useful marker in the determination of the infiltrative behaviour of these tumors

Flavour physics from an approximate U(2)^3 symmetry

The quark sector of the Standard Model exhibits an approximate U(2)^3 flavour symmetry. This symmetry, broken in specific directions dictated by minimality, can explain the success of the Cabibbo-Kobayashi-Maskawa picture of flavour mixing and CP violation, confirmed by the data so far, while allowing for observable deviations from it, as expected in most models of ElectroWeak Symmetry Breaking. Building on previous work in the specific context of supersymmetry, we analyze the expected effects and we quantify the current bounds in a general Effective Field Theory framework. As a further relevant example we then show how the U(2)^3 symmetry and its breaking can be implemented in a generic composite Higgs model and we make a first analysis of its peculiar consequences. We also discuss how some partial extension of U(2)^3 to the lepton sector can arise, both in general and in composite Higgs models. An optimistic though conceivable interpretation of the considerations developed in this paper gives reasons to think that new physics searches in the flavour sector may be about to explore an interesting realm of phenomena.Comment: 29 pages, 5 figure