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The 2016 Global Burden of Disease report by WHO revealed that diseases of the gastrointestinal tract (GIT) had one of the highest incidence rates worldwide. The plethora of factors that contribute to the development of GIT-related illnesses can be divided into genetic, environmental and lifestyle factors. Apart from that, the role that infectious agents play in the development of GIT diseases has piqued the interest of researchers worldwide. The human gut harbors approximately 1014 bacteria in it with increasing concentration toward the lower GIT. Among the various microbiota that colonize the human gut, Gram-negative bacteria have been most notoriously linked to GIT-related diseases such as inflammatory bowel disease (IBD) including Crohn's disease and ulcerative colitis and colorectal cancer (CRC). Some of the notable culprits that have been attributed to these diseases are Bacteroides fragilis, Fusobacterium nucleatum, Escherichia coli and Helicobacter pylori. However, studies in recent years are beginning to recognize a new player, Klebsiella pneumoniae (K. pneumoniae) in the causation and progression of GIT diseases. Once synonymous with infections and diseases of the upper respiratory tract, K. pneumoniae has now emerged as one of the pathogens commonly isolated from patients with GIT diseases. However, extensive studies attributing K. pneumoniae to GIT diseases, particularly that of CRC are scanty. Therefore, this review intends to shed light on the association of K. pneumoniae in gastrointestinal diseases such as Crohn's disease, ulcerative colitis as well as CRC.

We find very strong and consistent evidence that investments in Strong-Governance firms (managers not entrenched) are strongly sensitive to availability of internal cash flows while such sensitivity is not different from zero for Weak-Governance firms (entrenched management). We interpret this as evidence in support of Kaplan and Zingales' (1997) contention that sensitivity of investments to cash flows is not an adequate measure of financing constraints. More importantly, our findings are consistent with Kaplan and Zingales’ conjecture that the observed sensitivity of investments to cash flows in firms that do not face financing constraints may be driven by excessive risk aversion of managers.

Interleukin 1 beta (IL-1 beta) is a proinflammatory cytokine that maintains thermal hyperalgesia and facilitates the release of calcitonin gene-related peptide from rat cutaneous nociceptors in vivo and in vitro. Brief applications of IL-1 beta to nociceptive neurons yielded a potentiation of heat-activated inward currents (Iheat) and a shift of activation threshold toward lower temperature without altering intracellular calcium levels. The IL-1 beta-induced heat sensitization was not dependent on G-protein-coupled receptors but was mediated by activation of protein kinases. The nonspecific protein kinase inhibitor staurosporine, the specific protein kinase C inhibitor bisindolylmaleimide BIM1, and the protein tyrosine kinase inhibitor genistein reduced the sensitizing effect of IL-1 beta whereas negative controls were ineffective. RT-PCR and in situ hybridization revealed IL-1RI but not RII expression in neurons rather than surrounding satellite cells in rat dorsal root ganglia. IL-1 beta acts on sensory neurons to increase their susceptibility for noxious heat via an IL-1RI/PTK/PKC-dependent mechanism.

Different test results have been reported for the same chemicals in two in vitro chromosome aberration test systems, CHL cells tested by a Japanese protocol and CHO cells tested by the US National Toxicology Program [Sofuni et al., Mutat Res 241:173-213,1990]. Here, laboratories in Japan, the US and the UK tested 9 such chemicals in CHL and CHO cells using the same protocols and found all 9 positive in both cell types; differences in earlier conclusions with these chemicals were due mainly to test protocol, not to different sensitivities of the cells. The most important protocol difference is sampling time. Chemicals that were negative in the NTP series using a sampling time of 10 to 13 hours often produced positive results when retested here with a 20- to 24-hour sampling time. While positive results were obtained in both cell types, CHL cells sometimes had higher aberration levels and survived at higher doses than CHO cells would tolerate. This may reflect some intrinsic difference in sensitivity but may also be affected by factors such as cell cycle length and culture media (e.g., oxygen scavenging capacity). The collaboration reported here also contributed to a better understanding of scoring aberrations, especially "gaps"; there was good agreement on what types of aberrations should be included in the totals when scoring criteria were clearly defined, for example, many changes classified as "gaps" by the Japanese system were classified as "breaks" in the scoring systems used in the United States and the United Kingdom, and were appropriately included in total aberration counts.

For the estimation of population mean in simple random sampling, an efficient regression-type estimator is proposed which is more efficient than the conventional regression estimator and hence than mean per unit estimator, ratio and product estimators and many other estimators proposed by various authors. Some numerical examples are included for illustration.

When stratified random sampling is used for the estimation of population mean, use of ‘Combined ratio estimator’ is well known. Some improved estimators for population mean are proposed which are better than ‘Combined ratio estimator’ and some other well known existing ones, from the point of view of bias and mean square error. An empirical illustration is given.

For the estimation of the population mean in stratified random sampling a ‘Combined Product Estimator’ is proposed which is more efficient than the ‘Combined Ratio’ and ‘Separate Ratio’ estimators. Also, the proposed estimator have exact expressions for bias and mean square error. An empirical illustration is given to compare the efficiencies of different estimators.

The problem of estimation of ratio of population proportions is considered and a difference-type estimator is proposed using auxiliary information. The bias and mean squared error of the proposed estimator is found and compared to the usual estimator and also to WYNN'S (1976) type estimator. An example is included for illustration.