Considerable policy interest warrants a closer look at small and medium sized firms. Using an a sample of manufacturing plants from the Annual Respondents Database (ARD). I find that plants owned by small single firms have significantly lower productivity than larger non single plants. Decomposing aggregate productivity growth into the contributions of various plant types, I do not find any evi...

i t 1s a t t emted t o rev1ew 3200 c a s e s of herniat ed lumbar d isc t o point out the i ndic a tions for ope ra t i o n , the value o f myelog raphy . t he r esult o f ope rat ion and the caus e s o f comp l i cat i ons . we believe tha t myelography s houl d be performed i n a l most a ll patients. i n ne a rl y 96 .8 pe rcent of cases my e l o grams co r r e s pond to clinical f i ndings....

Binary pulsars with very small radial velocity corresponds to weak orbital effect at time scale of orbital period, and thus be treated as singular ones. However such pulsars may show their binary nature at long time scale by affecting pulsar frequency derivatives. Subtracting the magnetic dipole radiation predicted frequency derivatives from the measured ones, the intensity of long term orbital...

In this paper, we introduce a notion of generalized states from an EQ-algebra E1 to another EQ-algebra E2, which is a generalization of internal states (or state operators) on an EQ-algebra E. Also we give a type of special generalized state from an EQ-algebra E1 to E1, called generalized internal states (or GI-state). Then we give some examples and basic properties of generalized (internal) st...

M any pathogenic bacteria modulate the host actin assembly machinery to promote infection and spread. Enterohemorrhagic Escherichia coli (EHEC) O157:H7 is a food-borne pathogen that causes severe diarrhea that can be accompanied by hemolytic uremic syndrome with potentially fatal consequences. Pathogenesis of EHEC and a closely-related pathogen, enteropathogenic E. coli (EPEC), is associated wi...

In This Issue In This Issue Nuclear proteins get around rotein trafficking between the cytoplasm and the nucleus has been studied extensively; but how do proteins move from one site to another within the nu-cleus? On page 615, Leung and Lamond focus on the intranuclear trafficking of the RNA-binding protein NHPX, and describe an elegant series of experiments that demonstrates the existence of m...

The paper provides an extended local gauge transformation. By means of it, the Lagrangian of gauge fields with masses can keep unchanged in the continuous transformations. In this way, the Higgs mechanism becomes unnecessary and we do not need to suppose the existence of the Higgs particles. PACS numbers: 1110, 1130 According to the Yang-Mills theory, in order to keep the Lagrangian of a system...

Following optic nerve section (ONS) in goldfish, the right eye was repeatedly injected with tetrodotoxin (TTX) and the left eye with Ringer solution. At various survival periods after ONS, horseradish peroxidase (HRP) was applied to small groups of axons in dorsal or ventral retina in both eyes. Counts of labeled regenerating retinal axons show that 43 +/- 4.6% of regenerating axons course thro...

PURPOSE The pathogenesis of retinal ganglion cell loss in glaucoma remains incompletely understood. Current evidence suggests that the optic nerve (ON) head and axons are the main site of injury in glaucoma. This study compares changes in prosurvival and proapoptotic gene expression in ONs with those in retinas in three models of ocular injury, specifically ON transection (ONTX), N-methyl-D-asp...

The synthetic antioxidant ethoxyquin (EQ) is increasingly used in animal feeds and has been candidate for carcinogenicity testing. EQ has the potential for toxicological and adverse health effects for both fish and fish consumers through "carryover" processes. The toxicological aspects of EQ have not been systematically investigated. The present study was performed to investigate the hepatic me...