In this study, we analyze extensive segmented and standardized agricultural fields in the marginally productive terrain of the Pampa de Guereque in the Jequetepeque Valley on the north coast of Peru. Although portions of the associated canal system were constructed continuously from late Formative to Chimú times, the segmented fields date to the late Chimú–Inka period and were only partially finished, apparently never fully used, and ultimately abandoned. We provide description of field plots and irrigation canals and discuss the implications of state-level construction and labor management of the fields, as well as the probable reasons for their abandonment.

We describe the investigation of two temporally coincident illness clusters involving salmonella and Staphylococcus aureus in two states. Cases were defined as gastrointestinal illness following two meal events. Investigators interviewed ill persons. Stool, food and environmental samples underwent pathogen testing. Alabama: Eighty cases were identified. Median time from meal to illness was 5·8 h. Salmonella Heidelberg was identified from 27 of 28 stool specimens tested, and coagulase-positive S. aureus was isolated from three of 16 ill persons. Environmental investigation indicated that food handling deficiencies occurred. Colorado: Seven cases were identified. Median time from meal to illness was 4·5 h. Five persons were hospitalised, four of whom were admitted to the intensive care unit. Salmonella Heidelberg was identified in six of seven stool specimens and coagulase-positive S. aureus in three of six tested. No single food item was implicated in either outbreak. These two outbreaks were linked to infection with Salmonella Heidelberg, but additional factors, such as dual aetiology that included S. aureus or the dose of salmonella ingested may have contributed to the short incubation periods and high illness severity. The outbreaks underscore the importance of measures to prevent foodborne illness through appropriate washing, handling, preparation and storage of food.

Immunoglobulin A (IgA) is a predominant immunoglobulin present in human breast milk and is known to play an important role in infant gut immunity maturation. Breast milk composition varies between populations, but the environmental and maternal factors responsible for these variations are still unclear. We examined the relationship between different exposures and levels of IgA in colostrum. The objective of this study was to examine whether exposures analysed influence levels of IgA in colostrum. The present study used 294 colostrum samples from the MecMilk International cohort, collected from women residing in London, Moscow and Verona. Samples were analysed in automated Abbott Architect Analyser. We found an inverse correlation between time postpartum and colostrum total IgA level (r=−0.49, P<0.001). Adjusting for maternal parity, smoking, fresh fruit and fish consumption and allergen sensitization, multiple regression model showed that IgA levels were influenced by colostrum collection time (P<0.0001) and country of collection (P<0.01). Mode of delivery influence did not appear to be significant in univariate comparisons, once adjusted for the above maternal characteristics it showed a significant influence on total IgA (P=0.01). We conclude that the concentration of IgA in colostrum drops rapidly after birth and future studies should always consider this factor in analysis. IgA concentration varied significantly between countries, with the highest level detected in Moscow and lowest in Verona. Mode of delivery effect should be confirmed on larger cohorts. Further work is needed to determine ways to correct for IgA decline over time in colostrum, and to find the cause of variations in IgA levels between the countries.

Grass silage is typically fed to dairy cows in temperate regions. However, in vivo information on methane (CH4) emission from grass silage of varying quality is limited. We evaluated the effect of two rates of nitrogen (N) fertilisation of grassland (low fertilisation (LF), 65 kg of N/ha; and high fertilisation (HF), 150 kg of N/ha) and of three stages of maturity of grass at cutting: early maturity (EM; 28 days of regrowth), mid maturity (MM; 41 days of regrowth) and late maturity (LM; 62 days of regrowth) on CH4 production by lactating dairy cows. In a randomised block design, 54 lactating Holstein–Friesian dairy cows (168±11 days in milk; mean±standard error of mean) received grass silage (mainly ryegrass) and compound feed at 80 : 20 on dry matter basis. Cows were adapted to the diet for 12 days and CH4 production was measured in climate respiration chambers for 5 days. Dry matter intake (DMI; 14.9±0.56 kg/day) decreased with increasing N fertilisation and grass maturity. Production of fat- and protein-corrected milk (FPCM; 24.0±1.57 kg/day) decreased with advancing grass maturity but was not affected by N fertilisation. Apparent total-tract feed digestibility decreased with advancing grass maturity but was unaffected by N fertilisation except for an increase and decrease in N and fat digestibility with increasing N fertilisation, respectively. Total CH4 production per cow (347±13.6 g/day) decreased with increasing N fertilisation by 4% and grass maturity by 6%. The smaller CH4 production with advancing grass maturity was offset by a smaller FPCM and lower feed digestibility. As a result, with advancing grass maturity CH4 emission intensity increased per units of FPCM (15.0±1.00 g CH4/kg) by 31% and digestible organic matter intake (33.1±0.78 g CH4/kg) by 15%. In addition, emission intensity increased per units of DMI (23.5±0.43 g CH4/kg) by 7% and gross energy intake (7.0±0.14% CH4) by 9%, implying an increased loss of dietary energy with advancing grass maturity. Rate of N fertilisation had no effect on CH4 emissions per units of FPCM, DMI and gross energy intake. These results suggest that despite a lower absolute daily CH4 production with a higher N fertilisation rate, CH4 emission intensity remains unchanged. A significant reduction of CH4 emission intensity can be achieved by feeding dairy cows silage of grass harvested at an earlier stage of maturity.

In nature, biomolecules guide the formation of hierarchically-ordered, lightweight, inorganic-organic composites such as corals, shells, teeth and bones. M13 bacteriophage has been used to mimic bio-inspired material development due to its rigid, nanoscale rod-like morphology. Liquid-crystalline monolayers of genetically engineered phage have been used to template crystallization of thin layers of inorganic and metallic materials. We have created thin films composed of engineered M13 phage capable of binding inorganic components. We employed both a dip-cast and a drop-cast film fabrication method on both smooth and rough gold, silica and glass casting surfaces to create thin films and 3D structures of various degrees of hierarchical order. We have found the engineered M13 phage and the inorganic mineral significantly affected both film morphology and the mechanical properties of the film. Similarly, film fabrication parameters such as solution chemistry, temperature, and pulling speed affected film properties. Using a calcium phosphate biomineralized 4E phage, film thickness increased linearly with the number of layers/dips in the phage solution. The stiffness of these composites (Young's modulus) were >80 GPa for mineralized, multilayer films. These materials are an order of magnitude stiffer than the biological equivalent collagen. Stiffness, however, does not appear to increase in a multilayer film beyond a saturation point. Ultimately, we have developed a platform for phage-based bio-composites for developing high performance materials.

Satellite altimetric time series allow high-precision monitoring of ice-sheet mass balance. Understanding elevation changes in these regions is important because outlet glaciers along ice-sheet margins are critical in controlling flow of inland ice. Here we discuss a new airborne altimetry dataset collected as part of the ICECAP (International Collaborative Exploration of the Cryosphere by Airborne Profiling) project over East Antarctica. Using the ALAMO (Airborne Laser Altimeter with Mapping Optics) system of a scanning photon-counting lidar combined with a laser altimeter, we extend the 2003–09 surface elevation record of NASA’s ICESat satellite, by determining cross-track slope and thus independently correcting for ICESat’s cross-track pointing errors. In areas of high slope, cross-track errors result in measured elevation change that combines surface slope and the actual Δz/Δt signal. Slope corrections are particularly important in coastal ice streams, which often exhibit both rapidly changing elevations and high surface slopes. As a test case (assuming that surface slopes do not change significantly) we observe a lack of ice dynamic change at Cook Ice Shelf, while significant thinning occurred at Totten and Denman Glaciers during 2003–09.

Designing new materials with well-defined structures and desired functions is a challenge in materials science, especially with nanomaterials. Nature, however, solves design of these materials through a self-assembling, hierarchically ordered process. We have investigated the mechanisms by which the high- aspect ratio and unique surface chemistry of M13 bacteriophage can give rise to increasingly complex, hierarchically ordered, bundled phage structures with a wide range of material applications. A molecular dynamic simulation of the 3-D structure of a 20-nm section of wild type (WT) and mutant phage types were developed based on WT phage crystal structure and ab initio calculations. Simulations of these phage were then used to examine repulsive and attractive forces of the particles in solution. Examination of contact interactions between two WT phage indicated the phage were maximally attracted to each other in a head to tail orientation. A mutant phage (4E) with a higher negative surface charge relative to WT phage also preferentially ordered head to tail in solution. In contrast, a mutant phage (CLP8) with a net positive surface charge had minimal repulsion in a 90° orientation. Understanding the self-assembly process through molecular dynamic simulations and decomposition of fundamental forces driving inter- and intra-strand interactions has provided a qualitative assessment of mechanisms that lead to hierarchical phage bundle structures. Results from simulation agree with experimentally observed patterns from self-assembly. We anticipate using this system to further investigate development of hierarchical structures not only from biological molecules but also from synthetic materials.

Fractional passage rates form a fundamental element within modern feed evaluation systems for ruminants, but knowledge on feed-specific fractional passage is largely lacking. Commonly applied tracer techniques based on externally applied markers, such as chromium-mordanted neutral detergent fibre (Cr-NDF), have been criticised for behaving differently to feed particles. This study describes the use of the carbon stable isotope ratio (13C : 12C) as an internal digesta marker to quantify the fractional passage rate of concentrates through the digestive tract of dairy cows. In a crossover study, five dairy cows were fed low (24.6%) and high (52.6%) levels of concentrates (dry matter (DM) basis) and received a pulse-dosed Cr-NDF and 13C isotopes. The latter was administered orally by exchanging part of the dietary concentrates of low 13C natural abundance with a pulse dose of maize bran-based concentrates of high 13C natural abundance. Fractional passage rates from the rumen (K1) and from the large intestine (K2) were determined from faecal marker concentrations of Cr-NDF and of 13C in the DM (13C-DM), NDF (13C-NDF) and neutral detergent soluble (13C-NDS). No differences in K1 estimates were found for the two concentrate levels fed but significant differences between markers (P<0.001) were observed. Faecal Cr-NDF excretions gave lower K1 estimates (0.037–0.039/h) than 13C-DM (0.054–0.056/h) and 13C-NDF (0.061–0.063/h). The 13C-NDS was calculated by the difference of 13C in the DM and NDF, and K1 values (0.039–0.043/h) were comparable to Cr-NDF. Total mean retention time was considerably higher for Cr-NDF (40.9–42.0 h) as compared to 13C-DM and 13C-NDF (32.0–33.5 h; P<0.001). The accuracy of the curve fits for Cr-NDF and 13C-DM and 13C-NDF was overall good (mean prediction error of 9.9–13.9%). Fractional passage rate of Cr-NDF was comparable to studies where this marker was assumed to represent the fractional passage of roughages. However, K1 estimates based on the 13C : 12C ratio varied considerably from studies based on external markers. Our results suggest that the use of 13C isotopes as digesta passage markers can provide feed component-specific K1 estimates for concentrates and provides new insight into passage kinetics of NDF from technologically treated compound feed.

The current status of the DRIFT (Directional Recoil Identification From Tracks) experiment at Boulby Mine is presented, including the latest limits on the WIMP spin-dependent cross-section from 1.5 kg days of running with a mixture of CS2 and CF4. Planned upgrades to DRIFT IId are detailed, along with ongoing work towards DRIFT III, which aims to be the world’s first 10 m3-scale directional Dark Matter detector.

Background: Behavioral and psychological symptoms of dementia (BPSD) are common and are core symptoms of the condition. They cause considerable distress to the person with dementia and their carers and predict early institutionalization and death. Historically, these symptoms have been managed with anxiolytic and antipsychotic medication. Although potentially effective, such medication has been used too widely and is associated with serious adverse side-effects and increased mortality. Consequently, there is a need to evaluate non-pharmacological therapies for behavioral and psychological symptoms in this population. One such therapy is physical activity, which has widespread health benefits. The aim of this review is to summarize the current findings of the efficacy of physical activity on BPSD.

Method: Published articles were identified using electronic and manual searches. Rather than systematically aggregating data, this review adopted a rapid critical interpretive approach to synthesize the literature.

Results: Exercise appears to be beneficial in reducing some BPSD, especially depressed mood, agitation, and wandering, and may also improve night-time sleep. Evidence of the efficacy of exercise on improving other symptoms such as anxiety, apathy, and repetitive behaviors is currently weak or lacking.

Conclusion: The beneficial effect of exercise type, its duration, and frequency is unclear although some studies suggest that walking for at least 30 minutes, several times a week, may enhance outcome. The methodological shortcomings of current work in this area are substantial. The research and clinical implications of current findings are discussed.

Reducing greenhouse gas emissions and optimizing energy consumption are important for mitigating climate change and improving resource use efficiency. Strawberry (Fragaria xananassa Duch) crops are a key component of the UK soft fruit sector and potentially resource-intensive crops. This is the first study to undertake a detailed environmental impact assessment of all methods of UK strawberry production. A total of 14 systems with six additional sub-systems grown for between 1 and 3 years were identified. They were defined by the growing of short-day (Junebearer) or everbearer varieties, organic production, covering with polytunnels or grown in the open, soil-grown (with or without fumigation) or container-grown (with peat or coir substrate) and summer or spring planted. Pre-harvest, the global warming potential varied between 1·5 and 10·3 t CO2 equiv/ha/crop or 0·13 and 1·14 t CO2 equiv/t of class 1 fruit. Key factors included the use of tunnels, mulch and irrigation, sterilization of soil with fumigants and the use of peat substrate. Seasonal crops without covers grown where rotation of sufficient length reduced Verticillium (system 4) were the most efficient. System 4a (that did not use mulch) emitted 0·13 t CO2 equiv/t of class 1 fruit. A second or third cropping year in soil-grown systems prolonged the effect of mulch and soil fumigants. Greenhouse gases from system 4 (with mulch) averaged 0·30 t CO2 equiv/t of class 1 fruit after 3 years of cropping compared to 0·63 and 0·36 t CO2 equiv/t after 1 and 2 years, respectively.

The distribution of Burkholderia pseudomallei was determined in soil collected from a rural district in Papua New Guinea (PNG) where melioidosis had recently been described, predominately affecting children. In 274 samples, 2·6% tested culture-positive for B. pseudomallei. Pulsed-field gel electrophoresis using SpeI digests and rapid polymorphic DNA PCR with five primers demonstrated a single clone amongst clinical isolates and isolates cultured from the environment that was commonly used by children from whom the clinical isolates were derived. We concluded that individuals in this region most probably acquired the organism through close contact with the environment at these sites. Burkholderia thailandensis, a closely related Burkholderia sp. was isolated from 5·5% of samples tested, an observation similar to that of melioidosis-endemic areas in Thailand. This is the first report of an environmental reservoir for melioidosis in PNG and confirms the Balimo district in PNG as melioidosis endemic.

The deformation of copper with grain size less than 10 nm is investigated using a 2D continuum model incorporating atomistically-based constitutive relations. The local constitutive response of a series of symmetric and asymmetric tilt grain boundaries is obtained using an atomistic quasicontinuum method under tension and shear. The atomistic results show that it is possible to associate a constant maximum stress with each deformation mechanism triggered in the GB vicinity, i.e. GB sliding and decohesion, atom shuffling and partial dislocation emission. The GB strength is always found weaker in shear than in tension. This information is incorporated into a continuum polycrystalline model tested under compression. This model provides useful insights, in the absence of intragranular plasticity, into the onset of macroscopic quasi-plasticity, which results from GB sliding and collective grain rotation mechanisms.