A two-step framework to analyze local microstructure variations of paper sheets based on 3D image data is presented. First, a multi-stage workflow efficiently acquires a large set of highly resolved tomographic image data, which enables—in combination with statistical image analysis—the quantification of local variations and pairwise correlations of morphological microstructure characteristics on length scales ranging from micrometers to centimeters. Secondly, the microstructure is analyzed in terms of the local behavior of porosity, thickness, and further descriptors related to transportation paths. The power of the presented framework is demonstrated, showing that it allows one (i) to quantitatively reveal the difference in terms of local structural variations between a model paper before and after unidirectional compression via hard-nip calendering and that (ii) the field of view which is required to reliably compute the probability distributions of the considered local microstructure characteristics is at least 20 mm$^{2}$. The results elucidate structural differences related to local densification. In particular, it is shown how calendering transforms local variations in sheet thickness into marked local mass density variations. The obtained results are in line with experimental measurements of macroscopic properties (basis weight, Bekk smoothness parameters, thickness, and Gurley retention times).

The launch and subsequent motion of a projectile provide a context for several quantities that yearn to be optimised. Most notable is the horizontal range of the projectile, a problem dating back to Galileo and still studied in modern times; see, for example [1], [2], [3], [4]. In a different direction, the articles [5] and [6] provide a solution to the problem of finding the angle of launch that results in the trajectory of longest arc length.

Ice deformation and basal motion characterize the dynamical behavior of the Greenland ice sheet (GrIS). We evaluate the contribution of basal motion from ice deformation measurements in boreholes drilled to the bed at two sites in the western marginal zone of the GrIS. We find a sustained high amount of basal motion contribution to surface velocity of 44–73% in winter, and up to 90% in summer. Measured ice deformation rates show an unexpected variation with depth that can be explained with the help of an ice-flow model as a consequence of stress transfer from slippery to sticky areas. This effect necessitates the use of high-order ice-flow models, not only in regions of fast-flowing ice streams but in all temperate-based areas of the GrIS. The agreement between modeled and measured deformation rates confirms that the recommended values of the temperature-dependent flow rate factor A are a good choice for ice-sheet models.

Micronutrient deficiencies and suboptimal energy intake are widespread in rural Kenya, with detrimental effects on child growth and development. Sporadic school feeding programmes rarely include animal source foods (ASF). In the present study, a cluster-randomised feeding trial was undertaken to determine the impact of snacks containing ASF on district-wide, end-term standardised school test scores and nutrient intake. A total of twelve primary schools were randomly assigned to one of three isoenergetic feeding groups (a local plant-based stew (githeri) with meat, githeri plus whole milk or githeri with added oil) or a control group receiving no intervention feeding. After the initial term that served as baseline, children were fed at school for five consecutive terms over two school years from 1999 to 2001. Longitudinal analysis was used controlling for average energy intake, school attendance, and baseline socio-economic status, age, sex and maternal literacy. Children in the Meat group showed significantly greater improvements in test scores than those in all the other groups, and the Milk group showed significantly greater improvements in test scores than the Plain Githeri (githeri+oil) and Control groups. Compared with the Control group, the Meat group showed significant improvements in test scores in Arithmetic, English, Kiembu, Kiswahili and Geography. The Milk group showed significant improvements compared with the Control group in test scores in English, Kiswahili, Geography and Science. Folate, Fe, available Fe, energy per body weight, vitamin B12, Zn and riboflavin intake were significant contributors to the change in test scores. The greater improvements in test scores of children receiving ASF indicate improved academic performance, which can result in greater academic achievement.

The present study examines the effect of animal-source-food (ASF) intake on arm muscle area growth as part of a larger study examining causal links between ASF intake, growth rate, physical activity, cognitive function and micronutrient status in Kenyan schoolchildren. This randomised, controlled feeding intervention study was designed with three isoenergetic feeding interventions of meat, milk, and plain traditional vegetable stew (githeri), and a control group receiving no snack. A total of twelve elementary schools were randomly assigned to interventions, with three schools per group, and two cohorts of 518 and 392 schoolchildren were enrolled 1 year apart. Children in each cohort were given feedings at school and studied for three school terms per year over 2 years, a total of 9 months per year: cohort I from 1998 to 2000 and cohort II from 1999 to 2001. Food intake was assessed by 24 h recall every 1–2 months and biochemical analysis for micronutrient status conducted annually (in cohort I only). Anthropometric measurements included height, weight, triceps skinfold (TSF) and mid-upper-arm circumference (MUAC). Mid-upper-arm muscle area (MAMA) and mid-upper-arm fat area (MAFA) were calculated. The two cohorts were combined for analyses. The meat group showed the steepest rates of gain in MUAC and MAMA over time, and the milk group showed the next largest significant MUAC and MAMA gain compared with the plain githeri and control groups (P< 0·05). The meat group showed the least increase in TSF and MAFA of all groups. These findings have implications for increasing micronutrient intake and lean body mass in primary schoolchildren consuming vegetarian diets.

With the exception of iodine and Fe, there is still very limited information on the effect of micronutrients on cognitive function, especially among school-age children. The present analysis evaluates the relationship between dietary Fe, Zn and B vitamins (B12, B6, folate and riboflavin) and gains in cognitive test scores among school children in rural Kenya. Data for the present study were obtained from The Child Nutrition Kenya Project, a 2-year longitudinal, randomised controlled feeding intervention study using animal source foods. Dietary nutrient values were based on monthly and bimonthly 24 h recall data collected during the study period. In longitudinal regression analyses, available Fe, available Zn, vitamin B12 and riboflavin showed significant relationships with improved cognitive test scores, after controlling for confounders such as energy intake, school, socio-economic status and morbidity. Available Fe intake was associated with significantly higher gains in Raven's Coloured Progressive Matrices test scores over time. Available Zn intake was associated with significantly higher gains in digit span-total test scores over time, while vitamin B12 and riboflavin intakes were each associated with significantly higher gains in digit span-forward test scores over time. This analysis demonstrates the influence of improved dietary micronutrient status on school children's cognitive function.

Observational studies have shown that children in developing countries consuming diets containing high amounts of bioavailable nutrients, such as those found in animal-source foods, grow better. The present study investigated which specific nutrients from the diet of Kenyan school children predicted their growth. The children (n544, median age 7 years) participated in a 2-year long food supplementation study with animal-source foods. Height gain during the intervention period was positively predicted by average daily intakes of energy from animal-source foods, haem Fe, preformed vitamin A, Ca and vitamin B12. Weight gain was positively predicted by average daily intakes of energy from animal-source foods, haem Fe, preformed vitamin A, Ca and vitamin B12. Gain in mid-upper-arm muscle area was positively predicted by average daily intakes of energy from animal-source foods and vitamin B12. Gain in mid-upper-arm fat area was positively predicted by average daily intakes of energy from animal-source foods. Gain in subscapular skinfold thickness was not predicted by any of the nutrient intakes. Negative predictors of growth were total energy and nutrients that are contained in high amounts in plant foods. The study shows that growth was positively predicted by energy and nutrients that are provided in high amounts and in a bioavailable form in meat and milk, and their inclusion into the diets of children in developing countries should be part of all food-based programmes in order to improve micronutrient status and growth.

This article is to discuss the automatic continuity properties and the representation of disjointness preserving linear mappings on certain normal Fréchet algebras of complex-valued functions. This class of operators is defined by the condition that any pair of functions with disjoint cozero sets is mapped to functions with disjoint cozero sets, and subsumes the class of local operators. It turns out that such operators are always continuous outside some finite singularity set of the underlying topological space. Our main emphasis is on disjointness preserving operators from Fréchet algebras of differentiable functions. Such operators are shown to admit a canonical representation that involves weighted composition for the derivatives. This result extends the classical characterization of local operators as linear partial differential operators.

The photogalvanic effects, which require a system lacking inversion symmetry, become possible in SiGe based quantum well (QW) structures due to their built-in asymmetry. We report on observations of the circular and linear photogalvanic effects induced by infrared radiation in (001)-and (113)-orientedp–Si/Si1–xGex QW structures and analyse these observations in view of the possible symmetry of these structures. The circular photogalvanic effect arises due to optical spin orientation of free carriers in QWs with band splitting in k-space which results in a directed motion of free carriers in the plane of the QW. We discuss possible mechanisms that give rise to spin-splitting of the electronic subband states for different symmetries.