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Two multilaboratory investigations were conducted by SUSTAIN to assess variability in the measurement of vitamin A, the marker used to verify levels of vitamin premix addition to enriched/fortified food aid products, including the widely distributed corn-soy blend (CSB). CSB specifications identify AACC Approved Method 86-06 or equivalent methods for vitamin A analysis, however there is no requirement to demonstrate equivalency. CSB samples with known and blinded levels of vitamin A and a reference standard were analyzed by 16 laboratories using their respective methods. Calculated coefficients of variation across all laboratories and methods for unknown samples and reference standard were 35 and 7.1, respectively, suggesting the largest source of variation is the vitamin extraction procedure. Laboratories generally overestimated low levels and underestimated high levels of vitamin A within the range of 6000 and 16 000 IU/lb. Only two laboratories demonstrated excellent internal precision (300 IU vitamin A/lb) and reported values within 95 confidence interval for all blinded samples. Results of this study have implications both for quality control in food aid products (due to the use of vitamin A as a marker) and for regulatory oversight of vitamin A content in commercial food products.

In The Principles of Mathematics , Bertrand Russell famously puzzled over something he called the unity of the proposition. Echoing Russell, many philosophers have talked over the years about the question or problem of the unity of the proposition. In fact, I believe that there are a number of quite distinct though related questions all of which can plausibly be taken to be questions regarding the unity of propositions. I state three such questions and show how the theory of propositions defended in my recent book The Nature and Structure of Content (2007) answers them.

Assume that the only thing before you is a statue made of some alloy. Call those who think that there is one thing before you in such a case monists. Call those who think there are at least two things before you in such a case pluralists. The most common arguments for pluralism run as follows. The statue is claimed to have some property P that the piece of alloy lacks (or vice versa), and hence it is concluded that they are distinct. Most often, the predicates employed in such arguments to express the crucial property are predicates expressing 'temporal properties', such as existing at a certain time; or 'modal properties', such as possibly being spherical; or 'constitution properties' such as being made of a certain sort of material. In a recent paper, Kit Fine has noted that such predicates suffer from various defects that make it possible for the monist to plausibly resist the relevant versions of the pluralist's arguments. For this reason, Fine considers a number of predicates that do not suffer from these defects, and constructs new versions of the above argument using them. Fine argues that any attempt on the monist's part to resist his versions of the argument force the monist to adopt implausible positions in the philosophy of language. As against this, I argue that the monist has perfectly plausible responses to Fine's arguments that require the monist to adopt only quite reasonable positions in the philosophy of language.

Gram-negative pathogens are increasingly resistant to extended-spectrum cephalosporins (ESCs). Using a prospective, case-controlled observational study, we examined the prevalence and the risk factors for development of resistance to ESCs in group I beta-lactamase-producing organisms. Of the 386 isolates of Enterobacter species, Pseudomonas aeruginosa, Citrobacter species, and Serratia marsescens from 340 consecutive patients, 70 (18.1%) were resistant to ESCs; the highest rates of resistance were found among Citrobacter freundii (40.9%), Enterobacter cloacae (31.1%), and Enterobacter aerogenes isolates (18.9%). Patients' prior antibiotic use and the mean number of antibiotics used were significantly greater in association with resistant vs. susceptible isolates. Resistance was associated with prior use of ceftizoxime or cefotaxime (P = .008), ceftazidime (P = .004), and piperacillin (P = .001). Other antibiotics were not associated with resistance. Resistance was less frequent in patients receiving ESCs and an aminoglycoside. We conclude that prior use of ESCs is associated with the isolation of resistant group I beta-lactamase-producing organisms. Concomitant use of an aminoglycoside may decrease this risk.