82 research outputs found

    Unusual Behavior of D-Region Ionization Time at 18.2kHz During Seismically Active Days

    Get PDF

    Possibility of Recovering Iron Fines from Tailings by Hydrocyclone

    Get PDF
    Although India is having vast reserves of iron ore, lack of consistency with respect to Si02 /Al2 03 ratio makes these unsuitable to use directly in the blast furnace without proper beneficiation. Beneficiation processes mostly applicable are sizing, washing and jigging in case of hematite and magnetic and gravity separation in case of magnetite to obtain acceptable grade lumps and fines for agglomeration for further use in blast furnace. During the washing operations, enrichment with respect to iron is marginal and gangue reduction with particular refere-nce to favourable Si02 Al2 03 ratio is limited

    Whether and How Prepurchase Word of Mouth Affects Postpurchase Word of Mouth

    Get PDF
    Consumers often purchase new products based on online reviews and recommendations from both friends and strangers. Previous studies have extensively explored the effects of word of mouth (WOM) on the prepurchase stage, but little is known about whether WOM from friends or strangers can alter consumers' postpurchase behavior. The authors propose that positive WOM from distant (vs. close) others increases consumers' intention to share negative WOM when the product/service fails to perform to their satisfaction due to two distinctive motivations. First, consumers perceive that positive WOM from distant others might mislead more people, and, consequently, consumers expect their negative WOM to have a greater impact on helping others. Second, when receiving positive WOM from close others, they are less willing to publicly contradict the close others' WOM even though they believe the WOM is misleading. Studies 1a and 1b demonstrate the main effect of interpersonal closeness on negative WOM intention, while Study 2 reveals the dual mediating effects of anticipated impact and relationship norm. Studies 3 and 4 validate these mechanisms by showing the moderating role of the self-construal level while ruling out the role of impression management. This research offers practical implications for WOM management across different social ties

    Effect of preoperative oral bisoprolol on intraoperative outcomes in endoscopic sinus surgery

    Get PDF
    Background: Endoscopic sinus surgery (ESS) presents challenges in managing intraoperative bleeding and hemodynamic stability. This study evaluates the efficacy of pre-operative oral bisoprolol in improving surgical conditions and outcomes in ESS. Methods: This study was conducted between March 2021 and June 2022 at the department of anaesthesia, Bangabandhu Sheikh Mujib medical University, Dhaka, Bangladesh. This randomized controlled trial was conducted with 50 participants undergoing elective ESS, divided into bisoprolol and placebo groups. Result: The study involved 50 participants undergoing elective ESS, with 25 in the bisoprolol group and 25 in the placebo group. While demographic characteristics, such as age, weight, height, and gender distribution, showed no statistically significant differences between the groups. The placebo group experienced significantly higher estimated blood loss (421.72 ml vs. 156.24 ml, p<0.001) and postoperative hemoglobin levels (12.88 g/dl vs. 11.07 g/dl, p<0.001) compared to the bisoprolol group. Hemodynamic parameters, particularly heart rate, exhibited significant differences at various time points, with the bisoprolol group maintaining a higher heart rate post-premedication, intra-operatively, and post-operatively (p<0.05 for all). In the assessment of intraoperative bleeding using the Fromme-Boezaart scale, the placebo group demonstrated higher incidences of severe bleeding grades (3 and 4) compared to the bisoprolol group, with these differences being statistically significant (p<0.001). Conclusions: Pre-operative oral bisoprolol in ESS patients significantly reduces intraoperative bleeding and anesthetic requirements while maintaining hemodynamic stability. These findings suggest bisoprolol as a beneficial pre-operative medication in ESS, warranting further research to optimize surgical outcomes

    Understanding signaling cascades in melanoma

    Get PDF
    Understanding regulatory pathways involved in melanoma development and progression has advanced significantly in recent years. It is now appreciated that melanoma is the result of complex changes in multiple signaling pathways that affect growth control, metabolism, motility and the ability to escape cell death programs. Here we review the major signaling pathways currently known to be deregulated in melanoma with an implication to its development and progression. Among these pathways are Ras, B-Raf, MEK, PTEN, phosphatidylinositol-3 kinase (PI3Ks) and Akt which are constitutively activated in a significant number of melanoma tumors, in most cases due to genomic change. Other pathways discussed in this review include the [Janus kinase/signal transducer and activator of transcription (JAK/STAT), transforming growth factor-beta pathways which are also activated in melanoma, although the underlying mechanism is not yet clear. As a paradigm for remodeled signaling pathways, melanoma also offers a unique opportunity for targeted drug development.Fil: Lopez Bergami, Pablo Roberto. Sanford-burnham Medical Research Institute; Estados Unidos. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; ArgentinaFil: Fitchmann, B. Sanford-burnham Medical Research Institute; Estados UnidosFil: Ronai, Ze´ev. Sanford-burnham Medical Research Institute; Estados Unido

    A Role for ATF2 in Regulating MITF and Melanoma Development

    Get PDF
    The transcription factor ATF2 has been shown to attenuate melanoma susceptibility to apoptosis and to promote its ability to form tumors in xenograft models. To directly assess ATF2's role in melanoma development, we crossed a mouse melanoma model (Nras(Q61K)::Ink4a⁻/⁻) with mice expressing a transcriptionally inactive form of ATF2 in melanocytes. In contrast to 7/21 of the Nras(Q61K)::Ink4a⁻/⁻ mice, only 1/21 mice expressing mutant ATF2 in melanocytes developed melanoma. Gene expression profiling identified higher MITF expression in primary melanocytes expressing transcriptionally inactive ATF2. MITF downregulation by ATF2 was confirmed in the skin of Atf2⁻/⁻ mice, in primary human melanocytes, and in 50% of human melanoma cell lines. Inhibition of MITF transcription by MITF was shown to be mediated by ATF2-JunB-dependent suppression of SOX10 transcription. Remarkably, oncogenic BRAF (V600E)-dependent focus formation of melanocytes on soft agar was inhibited by ATF2 knockdown and partially rescued upon shMITF co-expression. On melanoma tissue microarrays, a high nuclear ATF2 to MITF ratio in primary specimens was associated with metastatic disease and poor prognosis. Our findings establish the importance of transcriptionally active ATF2 in melanoma development through fine-tuning of MITF expression

    Infected erythrocyte-derived extracellular vesicles alter vascular function via regulatory Ago2-miRNA complexes in malaria

    Get PDF
    Malaria remains one of the greatest public health challenges worldwide, particularly in sub-Saharan Africa. The clinical outcome of individuals infected with Plasmodium falciparum parasites depends on many factors including host systemic inflammatory responses, parasite sequestration in tissues and vascular dysfunction. Production of pro-inflammatory cytokines and chemokines promotes endothelial activation as well as recruitment and infiltration of inflammatory cells, which in turn triggers further endothelial cell activation and parasite sequestration. Inflammatory responses are triggered in part by bioactive parasite products such as hemozoin and infected red blood cell-derived extracellular vesicles (iRBC-derived EVs). Here we demonstrate that such EVs contain functional miRNA-Argonaute 2 complexes that are derived from the host RBC. Moreover, we show that EVs are efficiently internalized by endothelial cells, where the miRNA-Argonaute 2 complexes modulate target gene expression and barrier properties. Altogether, these findings provide a mechanistic link between EVs and vascular dysfunction during malaria infection

    Minerals, Toxic Heavy Metals, and Antioxidant Properties of Honeys from Bangladesh

    Get PDF
    The study reports on major and trace elements as well as antioxidant properties of honey samples from Bangladesh. Four major cationic elements, seven trace elements, and three heavy metals were determined in the 12 honey samples using atomic absorption spectrophotometer. Nutritional values in these honey samples were further investigated according to their antioxidant properties. The content of major elements was in the range of 62.75–616.58, 579.48–2219.43, 69.42–632.25, and 0.13–1.20mg/kg for sodium, potassium, magnesium, and calcium, respectively. The trace elements varied in the range of 0.41–28, 0.12–3.54, 1.54–2.85, 0.29– 0.59, 0.02–0.35, and 0.01–0.06mg/kg for iron, zinc, copper, nickel, cobalt, and cadmium, respectively. Among the heavy metals, only lead (0.17–2.19 mg/kg) was detected.The results of antioxidant analysis based on phenolics, flavonoids, ascorbic acid, reducing sugar, and proteins (as nonphenolic antioxidants) revealed that multifloral raw honey samples contain significantly higher levels of reducing agents than monofloral and commercial brand honeys. The study provides a useful insight on the minerals, heavy metals, and antioxidant properties of honey samples commonly consumed in Bangladesh and found to be rich source of antioxidants and minerals. Some samples might pose some risk to the health due to lead contamination

    Assessment of Toxicity and Beneficiary Effects of Garcinia pedunculata on the Hematological, Biochemical, and Histological Homeostasis in Rats

    Get PDF
    This study was undertaken to investigate the toxicological profile of a methanolic extract of Garcinia pedunculata fruit in rats by conducting hematological, biochemical, and histopathological examinations. Long Evans rats were divided into four groups, each with 6 animals, and were treated with three oral doses (250, 500, and 1000mg/kg) once daily for 21 days.The extract did not cause significant changes in body and relative organweight, percentwater content, or hematological parameters at any administered doses. However, a significant dose-dependent positive effect in serum lipid profile and all atherogenic indices including the cardiac risk ratio, Castelli’s risk index-2, and the atherogenic coefficient were observed. Significant increases in the levels of iron and decreases in serumalkaline phosphatase, alanine transaminase, and lactate dehydrogenase activities and the levels of serum glucose were noted when the extract was administered at the highest dose (1000mg/kg). Histopathological examination of the target tissues further confirmed that the extract was safe and had no observed toxicological features. Our study indicates that G. pedunculata fruit is nontoxic, has the potential to be effective against atherosclerosis, and may be used as a hepatoprotectant.The fruit extract is also beneficial to those with iron deficiency and hyperglycemia
    corecore