2,230 research outputs found
Advertising spending, firm performance, and the moderating impact of CSR
This article investigates the potential of corporate social responsibility (CSR) to influence the link between advertising spending and firm performance. Drawing upon the literature of CSR, we hypothesize that CSR positively moderates the relationship between advertising spending and firm performance. We focus on two types of firm performance: sales and firm value. Using two samples from both the hotel and restaurant industries, we found that firms with higher levels of CSR enjoy higher returns on advertising spending than firms with lower levels of CSR. We discuss the theoretical and managerial implications of these findings and provide direction for future research
Comparison of Clinical Outcomes Following Gefitinib and Erlotinib Treatment in NonāSmall-Cell Lung Cancer Patients Harboring an Epidermal Growth Factor Receptor Mutation in Either Exon 19 or 21
Background:Gefitinib and erlotinib, small-molecule kinase inhibitors that block epidermal growth factor receptor (EGFR) signaling, have demonstrated a dramatic response rate and prolonged progression-free survival (PFS) in patients harboring an activating EGFR mutation. We compared the clinical outcomes in gefitinib- and erlotinib-treated patients harboring EGFR mutations who had recurrent or metastatic nonāsmall-cell lung cancer (NSCLC).Methods:A total of 375 patients with recurrent or metastatic stage IIIB/IV NSCLC, who had either exon 19 deletion or the L858R mutation in exon 21, and had received either gefitinib (n = 228) or erlotinib (n = 147), were included in the study. A matched-pair case-control study design was implemented in the analysis, where 121 pairs of gefitinib-treated and erlotinib-treated patients were matched according to sex, smoking history, Eastern Cooperative Oncology Group performance status, and types of EGFR mutation.Results:The median age of all patients was 58 years (range, 30ā84), and more than half of patients had never been smokers (63.6%). Most patients had adenocarcinoma (98.3%) and good Eastern Cooperative Oncology Group performance status (0, 1) (90.9%). The median number of cycles of EGFR tyrosine kinase inhibitor (TKI) treatment was 12.7 in the gefitinib group and 10.8 in the erlotinib group. Of the 242 patients, 63 (26%) received EGFR TKI as first-line therapy. The overall response rates and disease control rates in the gefitinib- or erlotinib-treated groups were 76.9% versus 74.4% (p = 0.575) and 90.1% versus 86.8%, respectively (p = 0.305). There was no statistically significant difference with regard to PFS (median, 11.7 versus 9.6; p = 0.056) between the gefitinib- and erlotinib-treated groups. For patients receiving EGFR TKI as the first-line treatment, there was no significant difference between the two treatment groups in overall response rates (76.7% and 90.0%) (p = 0.431) and median PFS (11.7 versus 14.5 months) (p = 0.507).Conclusion:In NSCLC patients harboring EGFR mutation, treatment with gefitinib and erlotinib resulted in similar effectiveness
Improvement of Switching Speed of a 600-V Nonpunch-through Insulated Gate Bipolar Transistor Using Fast Neutron Irradiation
AbstractFast neutron irradiation was used to improve the switching speed of a 600-V nonpunch-through insulated gate bipolar transistor. Fast neutron irradiation was carried out at 30-MeV energy in doses of 1Ā ĆĀ 108Ā n/cm2, 1Ā ĆĀ 109Ā n/cm2, 1Ā ĆĀ 1010Ā n/cm2, and 1Ā ĆĀ 1011Ā n/cm2. Electrical characteristics such as currentāvoltage, forward on-state voltage drop, and switching speed of the device were analyzed and compared with those prior to irradiation. The on-state voltage drop of the initial devices prior to irradiation was 2.08Ā V, which increased to 2.10Ā V, 2.20Ā V, 2.3Ā V, and 2.4Ā V, respectively, depending on the irradiation dose. This effect arises because of the lattice defects generated by the fast neutrons. In particular, the turnoff delay time was reduced to 92 nanoseconds, 45% of that prior to irradiation, which means there is a substantial improvement in the switching speed of the device
Solution-Phase Synthesis of Heteroatom-Substituted Carbon Scaffolds for Hydrogen Storage
This paper reports a bottom-up solution-phase process for the preparation of pristine and heteroatom (boron, phosphorus, or nitrogen)-substituted carbon scaffolds that show good surface areas and enhanced hydrogen adsorption capacities and binding energies. The synthesis method involves heating chlorine-containing small organic molecules with metallic sodium at reflux in high-boiling solvents. For heteroatom incorporation, heteroatomic electrophiles are added to the reaction mixture. Under the reaction conditions, micrometer-sized graphitic sheets assembled by 3ā5 nm-sized domains of graphene nanoflakes are formed, and when they are heteroatom-substituted, the heteroatoms are uniformly distributed. The substituted carbon scaffolds enriched with heteroatoms (boron ~7.3%, phosphorus ~8.1%, and nitrogen ~28.1%) had surface areas as high as 900 m^2 g^(ā1) and enhanced reversible hydrogen physisorption capacities relative to pristine carbon scaffolds or common carbonaceous materials. In addition, the binding energies of the substituted carbon scaffolds, as measured by adsorption isotherms, were 8.6, 8.3, and 5.6 kJ mol^(ā1) for the boron-, phosphorus-, and nitrogen-enriched carbon scaffolds, respectively
Human microglial cells synthesize albumin in brain
Albumin has been implicated in Alzheimer's disease since it can bind to and transport amyloid beta, the causative agent; albumin is also a potent inhibitor of amyloid beta polymerization. In a pilot phase study of Human Brain Proteome Project, we found evidence that albumin may be synthesized in immortalized human microglial cells, human primary microglial cells, and human fetal and adult brain tissues. We also found the synthesis and secretion is enhanced upon microglial activation by Amyloid [beta]~1-42~, lipopolysaccharide treatment or human Alzheimer's brain
Sericea lespedeza (Lespedeza cuneata) whole plant extract enhances rat muscle mass and sperm production by increasing the activity of NO-cGMP pathway and serum testosterone
Purpose: To analyze the effects of an aqueous extract of Sericea lespedeza (SL) on rat male menopause.Methods: Levels of nitric oxide (NO), endothelial nitric oxide synthase (NOS), cGMP, and prostaglandin E2 (PGE2) in the penile corpus cavernosum of the rats were evaluated using appropriate kits. Serum levels of dihydrotestosterone (DHT), testosterone, sex hormone-binding globulin (SHBG), and 17-beta hydroxysteroid dehydrogenases (17Ī²-HSD) were measured with enzyme-linked immunosorbent assay kits. Total and motile sperms were counted on a hemocytometer. Histological changes in rat testis and epididymis were analyzed with hematoxylin and eosin staining.Results: The levels of NO, NOS, and cGMP (but not PGE2) increased in a dose-dependent manner (p< 0.05) upon administration of an aqueous extract of SL (AESL), while levels of DHT, 17Ī²-HSD, and testosterone increased in the group administered with 300 mg/kg of AESL. Epididymal sperm count increased by 24 % in such rats compared to controls (p < 0.05).Conclusion: The aqueous extract of SL improves sperm count and muscle mass in rats by increasing the levels of NO, NOS, cGMP and testosterone. Thus, SL extract can potentially be developed as an alternative therapeutic agent for clinical management of TDS.
Keywords: NO-cGMP, Testosterone, Hormones, Sperm count, Muscle mass, Sericea lespedeza, Lespedeza cuneat
Cloning, expression, purification, crystallization and X-ray crystallographic analysis of glucuronic acid dehyĀdrogenase from Chromohalobacter salexigens. Addendum
An addendum to the article by Ahn et al. [Acta Cryst. (2011) F67, 689ā691]
Akt1-Inhibitor of DNA binding2 is essential for growth cone formation and axon growth and promotes central nervous system axon regeneration.
Mechanistic studies of axon growth during development are beneficial to the search for neuron-intrinsic regulators of axon regeneration. Here, we discovered that, in the developing neuron from rat, Akt signaling regulates axon growth and growth cone formation through phosphorylation of serine 14 (S14) on Inhibitor of DNA binding 2 (Id2). This enhances Id2 protein stability by means of escape from proteasomal degradation, and steers its localization to the growth cone, where Id2 interacts with radixin that is critical for growth cone formation. Knockdown of Id2, or abrogation of Id2 phosphorylation at S14, greatly impairs axon growth and the architecture of growth cone. Intriguingly, reinstatement of Akt/Id2 signaling after injury in mouse hippocampal slices redeemed growth promoting ability, leading to obvious axon regeneration. Our results suggest that Akt/Id2 signaling is a key module for growth cone formation and axon growth, and its augmentation plays a potential role in CNS axonal regeneration
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