320 research outputs found

    Selective Photodegradation Using Titanate Nanostructures

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    Adsorption and photocatalytic degradation are considered as the most important ways of treating water from organic compounds. It would be very useful if the adsorption and photocatalytic properties are combined in the same catalyst used in the treatment. Titania is one of the best well-known photocatalysts. However, due to its poor selectivity, it is unfavorable for photocatalytic removal of highly toxic low-level organic pollutants in wastewater in the presence of other less toxic high-level pollutants. Recent trials to introduce selectivity for titania have been achieved via controlling the catalyst morphology or by modifying the catalyst surface. This chapter summarizes the control of selectivity of titanate nanostructures toward adsorption and/or photocatalytic degradation of toxic organic dyes. In the first part, the effect of morphologies of titanites on selective photocatalytic degradation of three food dyes (color yellow sunset, red allura, and red carmoisine) was discussed. In changing the morphology of titanite, each dye is being preferably adsorbed by one morphology and decomposing more rapidly. In the second part, the selective adsorption and/or photocatalytic degradation of methylene blue dye from mixed dye solution using sodium titanate (NaTNT), cobalt-doped titanate nanotubes (co-doped TNT), and the decorated one with gold nanoparticles has been discussed

    Repeated migration : A simulation experiment based on Scottish materials

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    A random sample of persons drawn from the Scottish Central Register was used to study the phenomenon of repeated migration in Scotland for the years 1939-1964. The existence of repeated migration flows in Scotland is established by the fact that a migrant, on the average, made approximately 2.315 moves compared with an overall average of 1.038 moves during that period. A study of the frequency of movement of the sample revealed that repeated migration is a characteristic of the single and young persons. Sex differential is of less importance than the age or marital status differentials. In general, changes in the life cycle from family formation to family dissolution are major stimuli for migration. The influence of past mobility experience in determining levels of future mobility, whether this past experience is expressed in terms of the frequency of previous movement or in terms of previous duration of residence, is investigated. The hypothesis that people who were more mobile in the past are more likely to move again in the future is tested and validated. These findings have considerable implications for the development of a general stochastic model of repeated migration. The model assumes that the propensity to migrate is not constant over time, but rather decreases as duration in the same place of residence increases, implying a linkage between previous mobility experience and future mobility prospects. The model also assumes that this propensity to migrate does not build up immediately after a move has occurred. There is probably some delay time during which the likelihood of a further move is negligible. The model is formulated in a simple mathematical form. It includes only three parameters defining respectively the general probability of moving, the delay time between a move and a subsequent move, and a constant term used to identify the mode of decline in the probability of moving in relation to the duration of residence since last move. The model is tested by means of a simulation technique. Hypothetical samples are simulated and a distribution of movement for each sample is generated. Such a distribution is compared with the actual distribution of movement and the Kolmogorov-Smirnov two sample test is used as a measure of goodness of fit of the model to the observed data. Simulation experimentation is a necessary media in order to minimize the value of Kolmogorov-Smirnov statistic to imply non- significant differences between the simulated and actual distributions of movement. Methods of locating optimum conditions operating upon a system which maximize or minimize features of it are utilized. These methods were developed by Box and associates for the study of chemical processes. According to these methods, the response surface is first represented by a plane whose coefficients are estimated using a suitably arranged experiment in the experimental region. The signs and magnitudes of the coefficients determine the direction of greatest gain in the response towards a near-stationary region. The response surface in this region is represented by a polynomial of higher degree than the first. The sig-ns and magnitudes of its coefficients determine the nature of the surface and consequently the minimum or mximum can be located using a few more extra points. These methods are adopted to determine the levels of model parameters which produce the best fit of the model to the observed data. Kolmogorov-Smirnov statistic is treated as the response to be minimized and the model parameters as the independent variables that yield this response.F our consecutive experiments comprising a total of 77 simulations are performed along the above lines. The final outcome of these experiments is a fall in the value of response to a level equal to 0.017 implying that the differences between the simulation and actual samples, with a high level of probability, are random variations and that the two samples are drawn from the same population. This indicates that the model efficiently describes the actual patterns of repeated migration in Scotland and may eventually be used as a general explanation of the repeated migration phenomenon. The effect of disaggregating the data by age and sex is assessed by fitting the model to selected age and sex subgroups. But certain constraints prevent such analysis from being thoroughly completed. However, the analysis suggests that sex and age variables as well as other relevant variables are important factors in formalizing a significant relationship between the probability of moving and the past history of movement

    Relative efficiency of replicated and non-replicated statistical designs in quantifying the variations in maize grain yield

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    Received: June 9th, 2021 ; Accepted: July 11th, 2021 ; Published: August 2nd, 2021 ; Correspondence: [email protected] field experiment was conducted at the Agricultural Research Station, Faculty of Agriculture, Alexandria University, Egypt, during the two successive summer seasons of 2018 and 2019. The main aim was to evaluate the relative efficiency of two groups of experimental designs in quantifying the variations in maize grain yield as influenced by sowing date (SD), plant density (PD) and phosphorous (P) fertilization, and their interactions. The single hybrid Giza 168 maize (Zea mays, L.) cultivar was used during both seasons. The experimental designs under evaluation included replicated (RCBD, SPD, SSPD and 3-DLD), in three replications, and nonreplicated (one-rep without and with center points, RCCD and PRCCD) designs. The 3-DLD design was more efficient, within the replicated group, than the RCBD (reference design) with relative efficiency of 3.68. The SPD and SSPD had higher relative efficiencies at the sub-plot and sub sub-plot levels compared to RCBD. Within the non-replicated designs, the one-rep with center points, RCCD and PRCCD were more efficient than one-rep without center points (reference design) in discriminating the more important factors affecting grain yield in maize cultivar Giza 168

    Lymphangiogenesis in Oral Squamous Cell Carcinoma: Correlation with VEGF-C Expression and Lymph Node Metastasis

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    Background. Oral squamous cell carcinoma (OSCC) is the most common oral malignancy that preferentially spreads to the cervical lymph node which, when involved, complicates the anticancer therapy and threatens the patient life. It was suggested that lymph node metastasis may be facilitated by lymphangiogenesis. VEGF-C is one of the most important lymphangiogenic inducers that promotes the lymphatic vessels growth and supports the survival of adult lymphatic endothelial cells. Methods. Lymphatic vessels density (LVD) and LV morphometry were digitally evaluated using D2-40. The expression of VEGF-C was also assessed using immunohistochemistry and real-time polymerase chain reaction in 6 normal oral mucosa cases and 72 cases of OSCC. The correlation between LVD and LV morphometry, VEGF-C, and lymph node metastasis was statistically assessed. Results. A positive cytoplasmic expression of VEGF-C was detected in both epithelial and connective tissue cells in 97% of OSCC, while all normal tissues reacted negatively. A greater expression of VEGF-C was associated with larger and more dilated LV and lymph node metastasis but not with LVD. Conclusion. VEGF-C is actively involved in the invasion and metastasis of OSCC via inducing morphological changes in LV. VEGF-C may be a promising target for anticancer therapy

    EFFECT OF SOME CHEMICAL MATERIAL AND GERMINATION MEDIA ON SEED GERMINATION AND GROWTH OF GRAFTED CASIMIROA TRANSPLANTS

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    This investigation was carried out in the plastic house of Horticulture Research Institute, Agriculture Research Center, Giza during two consequent seasons (2002 – 2003) and (2003 – 2004). The study was aimed to enhance growth of Casimiroa rootstock seedlings to reach grafting size in a short time, beside defineding the suitable method of grafting. In this concern, results revealed that seed soaked in MgSO4 at 5 % for 15 min. and planted in media consists of peat and sand at 1 : 1, was increased seed germination percentage (92.1 and 94.8 %) and minimized the germination period (19.1 and 19.3 days), as compared with the other treatments. Thus it reached to the grafting size at a period of (179 and 180 days) in both seasons, respectively. However, Dormex (hydrogen cyanamide) treatment at 2% gave the highest root length (24.6 and 24.8 cm), and number of roots per plant (19.4 and 19.0). Results also showed that shield budding by using soft wood grafts, gave the highest percentage of success (69.2 and 72.4%), shortest  period of bud / scion (23.0 and 24.0 days), highest values of scion length (26.5 and 25.7 cm) and highest leaf area (38.28 and 40.67 cm2). However, cleft grafting with softwood grafts increased average number of leaves per sprouted graft (6.0 and 6.6) and shoot scion diameter (0.6 and 0.5 cm). Generally, seeds treated with MgSO4 at 5% berfore sowing in media consists of peat and sand at 1 : 1 in volume, induced healthy and sizeable rootstocks in a short time. Moreover, grafting rootstocks by soft wood grafts was the best method

    Bone Fracture Toughness and Strength Correlate With Collagen Cross‐Link Maturity in a Dose‐Controlled Lathyrism Mouse Model

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    Collagen cross‐linking is altered in many diseases of bone, and enzymatic collagen cross‐links are important to bone quality, as evidenced by losses of strength after lysyl oxidase inhibition (lathyrism). We hypothesized that cross‐links also contribute directly to bone fracture toughness. A mouse model of lathyrism using subcutaneous injection of up to 500 mg/kg β‐aminopropionitrile (BAPN) was developed and characterized (60 animals across 4 dosage groups). Three weeks of 150 or 350 mg/kg BAPN treatment in young, growing mice significantly reduced cortical bone fracture toughness, strength, and pyridinoline cross‐link content. Ratios reflecting relative cross‐link maturity were positive regressors of fracture toughness (HP/[DHLNL + HLNL] r2 = 0.208, p < 0.05; [HP + LP]/[DHNL + HLNL] r2 = 0.196, p < 0.1), whereas quantities of mature pyridinoline cross‐links were significant positive regressors of tissue strength (lysyl pyridinoline r2 = 0.159, p = 0.014; hydroxylysyl pyridinoline r2 = 0.112, p < 0.05). Immature and pyrrole cross‐links, which were not significantly reduced by BAPN, did not correlate with mechanical properties. The effect of BAPN treatment on mechanical properties was dose specific, with the greatest impact found at the intermediate (350 mg/kg) dose. Calcein labeling was used to define locations of new bone formation, allowing for the identification of regions of normally cross‐linked (preexisting) and BAPN‐treated (newly formed, cross‐link‐deficient) bone. Raman spectroscopy revealed spatial differences attributable to relative tissue age and effects of cross‐link inhibition. Newly deposited tissues had lower mineral/matrix, carbonate/phosphate, and Amide I cross‐link (matrix maturity) ratios compared with preexisting tissues. BAPN treatment did not affect mineral measures but significantly increased the cross‐link (matrix maturity) ratio compared with newly formed control tissue. Our study reveals that spatially localized effects of short‐term BAPN cross‐link inhibition can alter the whole‐bone collagen cross‐link profile to a measureable degree, and this cross‐link profile correlates with bone fracture toughness and strength. Thus, cross‐link profile perturbations associated with bone disease may provide insight into bone mechanical quality and fracture risk. © 2014 American Society for Bone and Mineral Research.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/110745/1/jbmr2356.pd

    Evaluating the extent of reusability of CYP2C19 genotype data among patients genotyped for antiplatelet therapy selection

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    Purpose Genotype-guided antiplatelet therapy is increasingly being incorporated into clinical care. The purpose of this study is to determine the extent to which patients initially genotyped for CYP2C19 to guide antiplatelet therapy were prescribed additional medications affected by CYP2C19. Methods We assembled a cohort of patients from eight sites performing CYP2C19 genotyping to inform antiplatelet therapy. Medication orders were evaluated from time of genotyping through one year. The primary endpoint was the proportion of patients prescribed two or more CYP2C19 substrates. Secondary endpoints were the proportion of patients with a drug–genotype interaction and time to receiving a CYP2C19 substrate. Results Nine thousand one hundred ninety-one genotyped patients (17% nonwhite) with a mean age of 68 ± 3 years were evaluated; 4701 (51%) of patients received two or more CYP2C19 substrates and 3835 (42%) of patients had a drug–genotype interaction. The average time between genotyping and CYP2C19 substrate other than antiplatelet therapy was 25 ± 10 days. Conclusions More than half of patients genotyped in the setting of CYP2C19-guided antiplatelet therapy received another medication impacted by CYP2C19 in the following year. Given that genotype is stable for a patient’s lifetime, this finding has implications for cost effectiveness, patient care, and treatment outcomes beyond the indication for which it was originally performed

    Krüppel-Like Factor 6 Expression Changes during Trophoblast Syncytialization and Transactivates ßhCG and PSG Placental Genes

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    BACKGROUND: Krßppel-like factor-6 (KLF6) is a widely expressed member of the Sp1/KLF family of transcriptional regulators involved in differentiation, cell cycle control and proliferation in several cell systems. Even though the highest expression level of KLF6 has been detected in human and mice placenta, its function in trophoblast physiology is still unknown. METHODOLOGY/PRINCIPAL FINDINGS: Herein, we explored KLF6 expression and sub-cellular distribution in human trophoblast cells differentiating into the syncytial pathway, and its role in the regulation of genes associated with placental development and pregnancy maintenance. Confocal immunofluorescence microscopy demonstrated that KLF6 is expressed throughout human cytotrophoblast differentiation showing no evident modifications in its nuclear and cytoplasmic localization pattern. KLF6 transcript and protein peaked early during the syncytialization process as determined by qRT-PCR and western blot assays. Overexpression of KLF6 in trophoblast-derived JEG-3 cells showed a preferential nuclear signal correlating with enhanced expression of human β-chorionic gonadotropin (βhCG) and pregnancy-specific glycoprotein (PSG) genes. Moreover, KLF6 transactivated βhCG5, PSG5 and PSG3 gene promoters. Deletion of KLF6 Zn-finger DNA binding domain or mutation of the consensus KLF6 binding site abolished transactivation of the PSG5 promoter. CONCLUSIONS/SIGNIFICANCE: Results are consistent with KLF6 playing a role as transcriptional regulator of relevant genes for placental differentiation and physiology such as βhCG and PSG, in agreement with an early and transient increase of KLF6 expression during trophoblast syncytialization
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