Sorting presorted files

A new sorting algorithm is presented. Its running time is O(n(1+10g(F/n)) where F = I{(f,j); i < j and xi < xj}1 is the total number of inversions in the input sequence xn xn_1 xn_2 ... x2 xl• In other words, presorted sequences are sorted quickly, and completely unsorted sequences are sorted in O(n log n) steps. Note that F < n2/2 always. Furthermore, the constant of proportionality is fairly small and hence the sorting method is competitive with existing methods for not too large n

Sorting presorted files

A new sorting algorithm is presented. Its running time is O(n(1+10g(F/n)) where F = I{(f,j); i < j and xi < xj}1 is the total number of inversions in the input sequence xn xn_1 xn_2 ... x2 xl• In other words, presorted sequences are sorted quickly, and completely unsorted sequences are sorted in O(n log n) steps. Note that F < n2/2 always. Furthermore, the constant of proportionality is fairly small and hence the sorting method is competitive with existing methods for not too large n

Bioterrorism-related Inhalational Anthrax in an Elderly Woman, Connecticut, 2001

On November 20, 2001, inhalational anthrax was confirmed in an elderly woman from rural Connecticut. To determine her exposure source, we conducted an extensive epidemiologic, environmental, and laboratory investigation. Molecular subtyping showed that her isolate was indistinguishable from isolates associated with intentionally contaminated letters. No samples from her home or community yielded Bacillus anthracis, and she received no first-class letters from facilities known to have processed intentionally contaminated letters. Environmental sampling in the regional Connecticut postal facility yielded B. anthracis spores from 4 (31%) of 13 sorting machines. One extensively contaminated machine primarily processes bulk mail. A second machine that does final sorting of bulk mail for her zip code yielded B. anthracis on the column of bins for her carrier route. The evidence suggests she was exposed through a cross-contaminated bulk mail letter. Such cross-contamination of letters and postal facilities has implications for managing the response to future B. anthracis–contaminated mailings

Enrichment of intestinal Lactobacillus by enhanced secretory IgA coating alters glucose homeostasis in P2rx7 &#8722;/&#8722; mice

The secretory immunoglobulin A (SIgA) in mammalian gut protects the organism from infections and contributes to host physiology by shaping microbiota composition. The mechanisms regulating the adaptive SIgA response towards gut microbes are poorly defined. Deletion of P2rx7, encoding for the ATP-gated ionotropic P2X7 receptor, leads to T follicular helper (Tfh) cells expansion in the Peyer\u2019s patches (PPs) of the small intestine, enhanced germinal centre (GC) reaction and IgA secretion; the resulting alterations of the gut microbiota in turn affects host metabolism. Here, we define gut microbiota modifications that correlate with deregulated SIgA secretion and metabolic alterations in P2rx7 12/ 12 mice. In particular, Lactobacillus shows enhanced SIgA coating in P2rx7 12/ 12 with respect to wild-type (WT) mice. The abundance of SIgA-coated lactobacilli positively correlates with Tfh cells number and body weight, suggesting Lactobacillus-specific SIgA response conditions host metabolism. Accordingly, oral administration of intestinal Lactobacillus isolates from P2rx7 12/ 12 mice to WT animals results in altered glucose homeostasis and fat deposition. Thus, enhanced SIgA production by P2X7 insufficiency promotes Lactobacillus colonization that interferes with systemic metabolic homeostasis. These data indicate that P2X7 receptor-mediated regulation of commensals coating by SIgA is important in tuning the selection of bacterial taxa, which condition host metabolism

Smoothsort's behavior on presorted sequences

In [5], Mehlhorn presented an algorithm for sorting nearly sorted sequences of length n in time 0(n(1+log(F/n))) where F is the number of initial inversions. More recently, Dijkstra[3] presented a new algorithm for sorting in situ. Without giving much evidence of it, he claims that his algorithm works well on nearly sorted sequences. In this note we show that smoothsort compares unfavorably to Mehlhorn's algorithm. We present a sequence of length n with O(nlogn) inversions which forces smoothsort to use time Omega(nlog n), contrasting to the time O(nloglogn) Mehlhorn's algorithm would need