Standard Pig Iron Samples.

Iron absorptive function of neonatal pig intestine.

To define the iron absorptive phase across the intestinal mucosa of neonatal pigs, the final SgFe concentration ratio of serosal to mucosal medium of everted gut sac at 1 hr incubation was measured. With .2 btg carrier iron (ferric citrate with molecular weight of 1,500) per milliliter of both the serosal and mucosal medium, the duodenum transported the iron against the concentration gradient f...

Gamma Spectrometric Analysis of Iron Ore Samples of Arak, Iran

Introduction Iron ore is one of the most important natural raw materials that is widely used for manufacturing iron and steel. This type of ore contains various amounts of radionuclides; thus, exposing workers handling their extraction, transportation, and processing to radiation. Materials and Methods In this study, 12 ore samples (each mass weighing about 2 kg) were collected from the iron or...

[Strangulation of penis with a pig iron metal ring].

Standard error correction in two-stage estimation with nested samples

Data at different levels of aggregation are often used in two-stage estimation, with estimates obtained at the higher level of aggregation entering the estimation at the lower level of aggregation. An example is customers within markets: first-stage estimates on market data provide variables that enter the second-stage model on customers. We derive the asymptotic covariance matrix of the second...

Robust Standard Errors in Small Samples: Some Practical Advice∗

In this paper we discuss the properties of confidence intervals for regression parameters based on robust standard errors. We discuss the motivation for a modification suggested by Bell and McCaffrey (2002) to improve the finite sample properties of the confidence intervals based on the conventional robust standard errors. We show that the Bell-McCaffrey modification is a natural extension of a...