Iron minerals influence the environmental redox behaviour and mobility of metals including the long-lived radionuclide technetium. Technetium is highly mobile in its oxidized form pertechnetate (Tc(VII)O4 –), however, when it is reduced to Tc(IV) it immobilizes readily via precipitation or sorption. In low concentration tracer experiments, and in higher concentration XAS experiments, pertechnetate was added to samples of biogenic and abiotically synthesized Fe(II)-bearing minerals (bio-magnetite, bio-vivianite, bio-siderite and an abiotically precipitated Fe(II) gel). Each mineral scavenged different quantities of Tc(VII) from solution with essentially complete removal in Fe(II)-gel and bio-magnetite systems and with 84±4% removal onto bio-siderite and 68±5% removal onto bio-vivianite over 45 days. In select, higher concentration, Tc XAS experiments, XANES spectra showed reductive precipitation to Tc(IV) in all samples. Furthermore, EXAFS spectra for bio-siderite, bio-vivianite and Fe(II)-gel showed that Tc(IV) was present as short range ordered hydrous Tc(IV)O2-like phases in the minerals and for some systems suggested possible incorporation in an octahedral coordination environment. Low concentration reoxidation experiments with air-, and in the case of the Fe(II) gel, nitrate-oxidation of the Tc(IV)-labelled samples resulted in only partial remobilization of Tc. Upon exposure to air, the Tc bound to the Fe-minerals was resistant to oxidative remobilization with a maximum of ∼15% Tc remobilized in the bio-vivianite system after 45 days of air exposure. Nitrate mediated oxidation of Fe(II)-gel inoculated with a stable consortium of nitrate-reducing, Fe(II)-oxidizing bacteria showed only 3.8±0.4% remobilization of reduced Tc(IV), again highlighting the recalcitrance of Tc(IV) to oxidative remobilization in Fe-bearing systems. The resultant XANES spectra of the reoxidized minerals showed Tc(IV)-like spectra in the reoxidized Fe-phases. Overall, this study highlights the role that Fe-bearing biogenic mineral phases have in controlling reductive scavenging of Tc(VII) to hydrous TcO2-like phases onto a range of Fe(II)-bearing minerals. In addition, it suggests that on reoxidation of these phases, Fe-bound Tc(IV) may be octahedrally coordinated and is largely recalcitrant to reoxidation over medium-term timescales. This has implications when considering remediation approaches and in predictions of the long-term fate of Tc in the nuclear legacy.

Uraniferous particles from contaminated environmental samples were analysed by scanning electronmicroscopy with energy dispersive X-ray analysis (SEM-EDXA) and microfocus extended X-rayabsorption fine structure (mEXAFS) spectroscopy. The particles of interest are uranium oxides, whichwere released into the environment by the combustion of scrap depleted uranium (DU) metal at afactory in Colonie, New York, USA. Most of the identified particles appear to have primary, ‘asemitted’ morphologies; some have evidence of minor dissolution, including corrosion pitting.Polycrystalline and often hollow microscopic spheres were identified, which are similar to particlesproduced by DU munitions impacting armoured targets. They are attributed to the autothermicoxidation of melt droplets. The compositions of the analysed spheres are dominated by UO2+x withvariable amounts of U3O8, two of the least soluble and least bioaccessible phases of U. These particles,collected from dusts and soils, have survived more than 25 y in the terrestrial environment. This studyfurther supports the case for using Colonie as an analogue for battlefield DU contamination.

Field and greenhouse studies were conducted in 1995 and 1996 in Kansas to determine the efficacy of 21 herbicide treatments for control of tumble pigweed, Palmer amaranth, redroot pigweed, and two biotypes of common waterhemp in soybean. In field studies, nine of eleven preemergence treatments controlled all four species 90% or more. However, pendimethalin and trifluralin controlled Palmer amaranth, redroot pigweed, and tumble pigweed less than the other preplant incorporated and preemergence treatments. With the exception of flumiclorac and NAF-75, postemergence treatments controlled 75 to 90% of all four species. A biotype of common waterhemp collected in Iowa was not controlled by acetolactate synthase-inhibiting herbicides. Greenhouse results were similar to field experiments. Results suggest at least 90% control of these Amaranthus species is possible with proper herbicide selection.

A long-term study was established to determine the effects of rate, application method, and repeated applications of norflurazon on soil persistence and plant injury for sorghum, corn, and wheat. Preplant incorporated (PPI) and preemergence (PE) applications of norflurazon at 1.1 (1X) and 2.2 kg ai/ha (2X) initially were applied in 1981. Subplots were retreated in 1982 and 1983. Rotational crops were planted each year from 1982 to 1987. Evaluations taken in 1982 (14 months after initial treatment) showed slight injury to wheat, sorghum, and corn from 1X applications and significant injury from 2X applications. Evaluations 1 to 3 yr after final application indicated that repeated applications, even at the 1X rate, increased norflurazon residues and rotational crop injury. At both 1X and 2X rates, PPI treatments increased norflurazon persistence compared to PE applications.

Accelerator mass spectrometry (AMS) radiocarbon dates fail to provide conclusive evidence that all New World human fossils are younger than approximately 11,000 yr. Because fossil bones vary widely in preservation, their radiocarbon dates are not equally accurate. Molecular-level radiocarbon dating, which used individual amino acids to assess fossil diagenesis, revealed that dates on known-age, noncollagenous bone were underestimated by at least 2000 to 9000 yr. The significance is that >11,000-yr-old fossil bones with poor preservation would yield Holocene and not Pleistocene radiocarbon ages, regardless of what chemical pretreatment or 14C counting method was used. Irreplaceable evidence for Pleistocene-age fossils in the New World could be lost if the diagenesis of fossil bones is not evaluated before the bones are radiocarbon dated. In contrast, radiocarbon ages for collagenous fossils can be determined more accurately if 14C is measured in several individual amino acids that are isolated from collagenous bone protein. Molecular-level radiocarbon dating will greatly improve not only the accuracy of chronologies for human migrations and animal extinctions, but of all late Quaternary chronologies that are based upon the 14C dating of fossil proteins.

The emergence of invasive fungal wound infections (IFIs) in combat casualties led to development of a combat trauma-specific IFI case definition and classification. Prospective data were collected from 1133 US military personnel injured in Afghanistan (June 2009–August 2011). The IFI rates ranged from 0·2% to 11·7% among ward and intensive care unit admissions, respectively (6·8% overall). Seventy-seven IFI cases were classified as proven/probable (n = 54) and possible/unclassifiable (n = 23) and compared in a case-case analysis. There was no difference in clinical characteristics between the proven/probable and possible/unclassifiable cases. Possible IFI cases had shorter time to diagnosis (P = 0·02) and initiation of antifungal therapy (P = 0·05) and fewer operative visits (P = 0·002) compared to proven/probable cases, but clinical outcomes were similar between the groups. Although the trauma-related IFI classification scheme did not provide prognostic information, it is an effective tool for clinical and epidemiological surveillance and research.

Injection drug users (IDUs) have an elevated risk for carriage of Staphylococcus aureus, including methicillin-resistant S. aureus (MRSA). Cutaneous injection-related infections are common in IDUs but detailed studies are few. Based on a subsample of 218 individuals from a community-recruited cohort of IDUs at a supervised injection facility, we investigated the microbiology and related antibiotic susceptibility profiles of isolates from 59 wounds. Twenty-seven percent of subjects had at least one wound and 25 (43%) were culture positive for S. aureus alone [14 MRSA and 11 (19%) methicillin-susceptible (MSSA) isolates]. Sixteen of 18 MRSA isolates were classified as community associated (CA) by the presence of genes encoding for PVL. MRSA and MSSA occurred in mixed infection with other organisms on three and six occasions, respectively. All CA-MRSA isolates were susceptible to tetracycline, vancomycin and linezolid but only 13% were susceptible to clindamycin compared to 63% of MSSA isolates. The frequency of CA-MRSA is a cause for concern in wound infection in the IDU setting.

In 1954 N. Kimura proved that each idempotent in a semigroup is contained in a unique maximal subgroup of the semigroup and that distinct maximal subgroups are disjoint [13] (or see [6, pp. 21–23]). This generalized earlier results of Schwarz [14] and Wallace [15]. These maximal subgroups are important in the study of semigroups. If G is a group, then the collection S(G) of nonempty complexes of G is a semigroup and it is natural to inquire what properties of G are inherited by the maximal subgroups of S(G). There seems to be very little literature devoted to this subject. In [5, Theorem 2], with certain hypotheses placed on an idempotent, it was shown that if G is a lattice-ordered group (“1-group”) then a maximal subgroup of S(G) containing an idempotent satisfying these conditions admits a natural lattice-order. The main result of this note (Theorem 1) is that if Gis a representable 1-group and E is a normal idempotent of S(G) and a dual ideal of the lattice G, then the maximal subgroup of S(G) containing E admits a representable lattice-order.

The higher order chain rule for Fréchet and Hadamard differentiable mappings on topological linear spaces is proved and various formulae for (g°f)(n) (x) are given. Leibniz' theorem (in a very general form) is also proved.

In this paper it is shown that if G is a periodic Abelian group and ∣ G ∣ ≥ 6, then the only automorphisms of the semigroup of finite nonempty complexes of G are induced by automorphisms of G.

Subject classification (Amer. Math. Soc. (MOS) 1970): primary 20 M 15; secondary 20 K 30.

Seroprevalence of Coxiella burnetii, the causal agent of Q fever in humans, was examined in wild brown rat populations from 4 Oxfordshire farmsteads (n = 127), 9 Somerset homesteads (n = 98), and 1 captive enclosure (n = 88) in the UK. Seroprevalence ranged between 7 and 53%, the lowest being within the captive population and the highest on dairy farmsteads with sheep present. This is the first reported investigation of C. burnetii in wild rats outside India. We suggest that the high Seroprevalence among rats (i) provides evidence that wild rats constitute an important reservoir for C. burnetii in the UK, and (ii) explains why cats, as frequent predators of rats, are so important in the epidemiology of this disease.