a Raman scattering study

The longitudinal optical phonon of metallic nanotubes shifts by 23 cm−1 to lower energies when the nanotubes are deposited from a solution onto a substrate. The linewidth increases by 13 cm−1. The changes are explained in terms of shifts in the Fermi energy that influence the Kohn anomaly in the longitudinal optical phonon branch in metallic nanotubes. Using in situ electrochemical Raman measurements we show that the Fermi energy is 0.16 eV below its intrinsic value in metallic nanotubes in solution. Our results impact the application of Raman spectroscopy to distinguish between metallic and semiconducting tubes by examining the high-energy mode line shape

Cosmology as a search for overall equilibrium

9 pages, 1 figure.-- The original publication is available at www.springerlink.com.In this letter we will revise the steps followed by A. Einstein when he first wrote on cosmology from the point of view of the general theory of relativity. We will argue that his insightful line of thought leading to the introduction of the cosmological constant in the equations of motion has only one weakness: The constancy of the cosmological term, or what is the same, its independence of the matter content of the universe. Eliminating this feature, I will propose what I see as a simple and reasonable modification of the cosmological equations of motion. The solutions of the new cosmological equations give place to a cosmological model that tries to approach the Einstein static solution. This model shows very appealing features in terms of fitting current observations.Peer reviewe

A standardised bioassay method using a bench‐top spray tower to evaluate entomopathogenic fungi for control of the greenhouse whitefly, Trialeurodes vaporariorum

BACKGROUND: Bioassays evaluating entomopathogenic fungi (EPF) isolates for effective microbial control of whitefly are a fundamental part of the screening process for bioprotectants, but development of repeatable, robust bioassays is not straightforward. Currently, there is no readily available standardised method to test the efficacy of EPF on whitefly. Here, we describe the calibration and use of a spray tower to deliver a standardised protocol to assess EPF activity; the method was validated using 18 EPF from four genera in tests against greenhouse whitefly, Trialeurodes vaporariorum (Westwood). RESULTS: At 138 kPa, the sprayer delivered 0.062 mL mm−2 (620 L ha−1) and an even deposition of spray across the central 1590 mm2 of the spray area. Average conidial deposition for all EPF was 252 conidia mm−2 and equivalent to 2.5 × 1012 conidia ha−1 at an application concentration of 1 × 107 conidia mL−1. Conidial deposition of a test Beauveria bassiana suspension increased with increasing application concentration. Egg laying by T. vaporariorum adults was restricted to 177 mm2 using clip cages specifically designed to ensure that third‐instar T. vaporariorum received a uniform spray coverage. Nymphs occupied 373 ± 5 mm2 of the leaf after migrating during the first instar. Average T. vaporariorum mortality totaled 8–89% 14 days after application of 1 × 107 conidia mL−1 of each EPF isolate. CONCLUSION: Combining the calibrated sprayer and bioassay method provides a reliable, standardised approach to test the virulence of EPF against whitefly nymphs. This laboratory‐based assay is affordable, replicable and allows the user to alter the dose of conidia applied to the target

УПРАВЛІННЯ ФІНАНСОВИМИ РЕЗЕРВАМИ ПРИ ОПТИМІЗАЦІЇ ФІНАНСОВИХ ПОТОКІВ ПІДПРИЄМСТВА

Уточнена сутність фінансового резерву промислового підприємства. Встановлені характеристики функціонування системи управління фінансовими потоками з точки зору використання резерву на основі використання положень теорії масового обслуговування.The essence of financial reserve of industrial enterprise was concretized. The characteristics of performance of system of financial flows servicing on the basis of theory of queues with usage of financial reserves were defined

Loss of c-Jun N-terminal Kinase 1 and 2 Function in Liver Epithelial Cells Triggers Biliary Hyperproliferation Resembling Cholangiocarcinoma

Targeted inhibition of the c-Jun N-terminal kinases (JNKs) has shown therapeutic potential in intrahepatic cholangiocarcinoma (CCA)-related tumorigenesis. However, the cell-type-specific role and mechanisms triggered by JNK in liver parenchymal cells during CCA remain largely unknown. Here, we aimed to investigate the relevance of JNK1 and JNK2 function in hepatocytes in two different models of experimental carcinogenesis, the dethylnitrosamine (DEN) model and in nuclear factor kappa B essential modulator (NEMO)(hepatocyte-specific knockout (Deltahepa)) mice, focusing on liver damage, cell death, compensatory proliferation, fibrogenesis, and tumor development. Moreover, regulation of essential genes was assessed by reverse transcription polymerase chain reaction, immunoblottings, and immunostainings. Additionally, specific Jnk2 inhibition in hepatocytes of NEMO(Deltahepa)/JNK1(Deltahepa) mice was performed using small interfering (si) RNA (siJnk2) nanodelivery. Finally, active signaling pathways were blocked using specific inhibitors. Compound deletion of Jnk1 and Jnk2 in hepatocytes diminished hepatocellular carcinoma (HCC) in both the DEN model and in NEMO(Deltahepa) mice but in contrast caused massive proliferation of the biliary ducts. Indeed, Jnk1/2 deficiency in hepatocytes of NEMO(Deltahepa) (NEMO(Deltahepa)/JNK(Deltahepa)) animals caused elevated fibrosis, increased apoptosis, increased compensatory proliferation, and elevated inflammatory cytokines expression but reduced HCC. Furthermore, siJnk2 treatment in NEMO(Deltahepa)/JNK1(Deltahepa) mice recapitulated the phenotype of NEMO(Deltahepa)/JNK(Deltahepa) mice. Next, we sought to investigate the impact of molecular pathways in response to compound JNK deficiency in NEMO(Deltahepa) mice. We found that NEMO(Deltahepa)/JNK(Deltahepa) livers exhibited overexpression of the interleukin-6/signal transducer and activator of transcription 3 pathway in addition to epidermal growth factor receptor (EGFR)-rapidly accelerated fibrosarcoma (Raf)-mitogen-activated protein kinase kinase (MEK)-extracellular signal-regulated kinase (ERK) cascade. The functional relevance was tested by administering lapatinib, which is a dual tyrosine kinase inhibitor of erythroblastic oncogene B-2 (ErbB2) and EGFR signaling, to NEMO(Deltahepa)/JNK(Deltahepa) mice. Lapatinib effectively inhibited cystogenesis, improved transaminases, and effectively blocked EGFR-Raf-MEK-ERK signaling. Conclusion: We define a novel function of JNK1/2 in cholangiocyte hyperproliferation. This opens new therapeutic avenues devised to inhibit pathways of cholangiocarcinogenesis

Diabetic ketoacidosis

Diabetic ketoacidosis (DKA) is the most common acute hyperglycaemic emergency in people with diabetes mellitus. A diagnosis of DKA is confirmed when all of the three criteria are present — ‘D’, either elevated blood glucose levels or a family history of diabetes mellitus; ‘K’, the presence of high urinary or blood ketoacids; and ‘A’, a high anion gap metabolic acidosis. Early diagnosis and management are paramount to improve patient outcomes. The mainstays of treatment include restoration of circulating volume, insulin therapy, electrolyte replacement and treatment of any underlying precipitating event. Without optimal treatment, DKA remains a condition with appreciable, although largely preventable, morbidity and mortality. In this Primer, we discuss the epidemiology, pathogenesis, risk factors and diagnosis of DKA and provide practical recommendations for the management of DKA in adults and children

Beleweniswêreld van die straatkind in Hillbrow

The street child that is driven by circumstances to live outside the supportive structure of the family, is on his own. He doesn’t have the educational developmental opportunities that children who grow up in families and societies do. He finds himself in a unique educational and living environment. From an educational psychologist’s point of view, this environment is abnormal. It is therefore a great challenge for the educational psychologist to try and avoid or resolve negative effects of the child's living environment. An exploratory-, descriptive-, contextual- and qualitative study was done, with the aim of gaining insight and understanding into the life of the street child in Hillbrow as well as his experiences of his situation. The results obtained from the interviews were placed in four categories. These categories are: The street child’s continuous struggle to survive, his need for a “normal child life” , his inability to accept responsibility and the presence of a normative awareness within the street child. In conclusion it is clear that the experiential world of the street child is multi-facetted. In general it appears that the street child has many limitations and difficulties which he experiences, and that input by an educational psychologist can have meaningful influence in his life