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Recent research suggests that variation exists among and between Oldowan stone tool assemblages. Oldowan variation might represent differential constraints on raw materials used to produce these stone implements. Alternatively, variation among Oldowan assemblages could represent different methods that Oldowan producing hominins utilized to produce these lithic implements. Identifying differential patterns of stone tool production within the Oldowan has implications for assessing how stone tool technology evolved, how traditions of lithic production might have been culturally transmitted, and for defining the timing and scope of these evolutionary events. At present there is no null model to predict what morphological variation in the Oldowan should look like. Without such a model, quantifying whether Oldowan assemblages vary due to raw material constraints or whether they vary due to differences in production technique is not possible. This research establishes a null model for Oldowan lithic artifact morphological variation. To establish these expectations this research 1) models the expected range of variation through large scale reduction experiments, 2) develops an algorithm to categorize archaeological flakes based on how they are produced, and 3) statistically assesses the methods of production behavior used by Oldowan producing hominins at the site of DK from Olduvai Gorge, Tanzania via the experimental model. Results indicate that a subset of quartzite flakes deviate from the null expectations in a manner that demonstrates efficiency in flake manufacture, while some basalt flakes deviate from null expectations in a manner that demonstrates inefficiency in flake manufacture. The simultaneous presence of efficiency in stone tool production for one raw material (quartzite) and inefficiency in stone tool production for another raw material (basalt) suggests that Oldowan producing hominins at DK were able to mediate the economic costs associated with stone tool procurement by utilizing high-cost materials more efficiently than is expected and low-cost materials in an inefficient manner.

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PURPOSE: Currently, research is lacking regarding the use of spill-proof beverage containers (SPBCs). The purpose of this study was to assess the relationship between daytime SPBCs use for sugared beverages, caries, socioeconomic status, and other covariates in high-caries risk 12- to 49-month-old children attending a Women, Infants and Children (WIC) program. METHODS: Data were analyzed using baseline information from 415 Iowa WIC-enrolled children who participated in a psychoeducational study. Mothers completed a series of detailed questionnaires regarding their SES and their child's beverage consumption. Dental examinations using d1d2.3 (noncavitated and cavitated carious lesions) criteria were completed for the children. Bivariate relationships for consumption of any sugared beverage using SPBCs were assessed and followed by multivariable modeling using logistic regression (alpha=0.05). RESULTS: Only 18 children (four percent) reported using SPBCs for any sugared beverage during the night versus 290 (70 percent) during the day. Daytime consumption of sugared beverages from SPBCs was less likely to be reported in older children (P<.001) and in African American children when compared to both Hispanics (P>.001) and Caucasians (P=.001). CONCLUSIONS: Iowa WIC children primarily consume sugared beverages using spill-proof beverage containers during the day; children who were younger and Hispanic or Caucasian were more likely to use SPBCs to consume sugared beverages.

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A block of an injury instrument will be left in wounds sometimes, and the suspect instrument can be discriminated by comparison with the block that was left through elemental analysis. In this study, three brands (Shibazi, Zhangxiaoquan, Qiaoxifu) of kitchen knives with forged, chop, and slice application series were analyzed by inductively coupled plasma atomic emission spectroscopy (ICP-AES) and Infrared Absorption to investigate the type, number of elements and the reference range used for comparing. The results show that when regarding one or more element as the discriminative threshold, together with 5% relative standard deviation (RSD) as the reference range, all the samples could be distinguished among different series. Furthermore, within the same series, the discriminative capability could reach up to 88.57% for all samples. In addition, elements with high content, such as Cr, Mn, and C, were useful to discriminate among different series, and trace elements, such as Ni, Si, and Cu, were useful within the same series. However, in practice, it is necessary to evaluate the accuracy of the method by Standard Reference Material (SRM) before an examination is performed.

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BACKGROUND: Middle Palaeolithic stone artefacts referred to as 'Levallois' have caused considerable debate regarding issues of technological predetermination, cognition and linguistic capacities in extinct hominins. Their association with both Neanderthals and early modern humans has, in particular, fuelled such debate. Yet, controversy exists regarding the extent of 'predetermination' and 'standardization' in so-called 'preferential Levallois flakes' (PLFs). METHODOLOGY/PRINCIPAL FINDINGS: Using an experimental and morphometric approach, we assess the degree of standardization in PLFs compared to the flakes produced during their manufacture. PLFs possess specific properties that unite them robustly as a group or 'category' of flake. The properties that do so, relate most strongly to relative flake thicknesses across their surface area. PLFs also exhibit significantly less variability than the flakes generated during their production. Again, this is most evident in flake thickness variables. A further aim of our study was to assess whether the particular PLF attributes identified during our analyses can be related to current knowledge regarding flake functionality and utility. CONCLUSIONS/SIGNIFICANCE: PLFs are standardized in such a manner that they may be considered 'predetermined' with regard to a specific set of properties that distinguishes them statistically from a majority of other flakes. Moreover, their attributes can be linked to factors that, based on current knowledge, are desirable features in flake tools (e.g. durability, capacity for retouch, and reduction of torque). As such, our results support the hypothesis that the lengthy, multi-phase, and hierarchically organized process of Levallois reduction was a deliberate, engineered strategy orientated toward specific goals. In turn, our results support suggestions that Levallois knapping relied on a cognitive capacity for long-term working memory. This is consistent with recent evidence suggesting that cognitive distinctions between later Pleistocene hominins such as the Neanderthals and anatomically modern humans were not as sharp as some scholars have previously suggested.

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Feeding development in infants is important not only for of the purpose of acquiring nutrition but also for developing the ability to intake liquids. Our previous study showed that the introduction of a straw was appropriate after an infant has acquired the ability to sip liquid from a spoon and/or cup. In this study, we investigated the effect of a bowlshaped spoon on liquid intake. The aim of this study was to determine the appropriate form of spoon for infant feeding development. Eleven healthy infants (3 girls and 8 boys, 10-18 months old, mean age: 13.3 months) were recruited with their guardians' consent. We made 3 types of prototype spoon: A, oval (a standard renge soup spoon); B, flared-out (with the margin of the bowl flared out); and C, hemispherical (with a hemispherical bottom, and smaller than type A or B). We observed infants taking liquid supported by their mothers and evaluated the following responses: 1) confusion with regard to lip position, 2) spillage and 3) choking. Type C showed statistically less confusion with regard to lip position than type A or B (p<0.01), and B showed less than type A (p<0.05). No statistically significant differences were observed in spillage or choking among the three types of spoon. The renge soup spoon is often used to smooth the transition from breast/bottle to cup feeding. In this study, we demonstrated the appropriate spoon form for infant feeding development.

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Intricately decorated Lapita pottery (3100-2700 BP) was made and deposited by the prehistoric colonizers of Pacific islands, east of the main Solomon's chain. For decades, analyses of this pottery have focused on the ancestor-descendant relationships of populations and the relative degree of interaction across the region to explain similarities in Lapita decoration. Cladistic analyses, increasingly used to examine the evolutionary relationships of material culture assemblages, have not been conducted on Lapita artefacts. Here, we present the first cladistic analysis of Lapita pottery and note the difficulties in using cladistics to investigate datasets where a high degree of horizontal transmission and non-branching evolution may explain observed variation. We additionally present NeighborNet and phenetic distance network analyses to generate hypotheses that may account for Lapita decorative similarity.

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Many wine connoisseur claim that the glass shape has a direct impact on wine aroma. This hypothesis was investigated in healthy volunteers (85 m, 96 f; age 19-73 years); 89 subjects received red wine, 92 subjects white wine. Subjects compared three glasses with a white wine and three glasses with a red. Glasses were of different shape but of the same height and of comparable opening diameter. All glasses had elegant stems; two glasses of 'tulip' and 'beaker'-like shapes were used in sessions with red and white wines. Different bulbous glasses were used in either red or white wine sessions. Subjects were blinded whether they received one or more wines. Intensity, hedonic tone, and quality of the wines were rated repeatedly before and after drinking. Ratings of wine odors from different glasses were influenced by glass shape. Importantly, this appeared not to relate to the esthetic impression the glasses made. Thus, the present data indicate that the shape of glasses seems to influence the perception of wine odors.

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OBJECTIVE: To evaluate acceptability, compliance and attitude towards the use of iron pots compared with aluminium pots, for cooking in a community that traditionally did not use iron pots. DESIGN: Randomised trial. SETTING: Two rural Malawian villages. SUBJECTS: Fifty-two households received iron pots and 61 aluminium pots. RESULTS: Pot characteristics were assessed by a questionnaire after 3, 6, 11 and 20 weeks of use. Within households using iron pots there was a significant decrease in acceptability score with usage, from an initial value of 13.7 to 11.4 (range 1-20) Answers to questions concerning cooking characteristics showed that after 3 weeks' use the aluminium pot scored better, whereas after 20 weeks fewer answers differed between the iron and aluminium pot groups. Almost a third of the households planned to continue using iron pots daily after 20 weeks, although they had ready access to their former aluminium pot. The presence of a group of consistent pot users suggests that if households were convinced about daily use, then they were likely to maintain consistent use. Some householders considered that iron pots required less firewood for cooking than aluminium pots. The main problems related to lower acceptability were rusting and pot weight. About 25% of problems with iron pots were unrelated to their cast iron characteristics. Overall 23.4% of the households indicated they would buy an iron pot. CONCLUSIONS: The low acceptability of iron pots for cooking could limit their value as an intervention to control iron-deficiency anaemia. Design modifications and better instructions on pot use should improve acceptability. The study highlights the need to assess the acceptability of interventions in order to facilitate their adoption in traditional communities.

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Há grande variedade de materiais empregados na confecção de utensílios para os alimentos: barro, ferro, vidro, inox, pedra, alumínio e outros. Cerca de 43 por cento de panelas vendidas atualmente nos Estados Unidos são de aço inoxidável. Outra parcela da população utiliza utensílios de alumínio. Este artigo visa especular a contribuição nutricional de utensílios usados na preparação de alimentos e feito de três diferentes materiais (alumínio, ferro e aço inoxidável), através de revisão de literatura científica

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To determine the efficacy of cooking food in iron pots to prevent anemia in premature infants, a longitudinal study on iron nutritional status was conducted in preterm, healthy infants from families of low socioeconomic level between mo 4 and 12 of life. The infants were divided randomly into two groups. The study group consisted of 22 infants whose food was cooked in iron pots; the control group consisted of 23 infants whose food was cooked in aluminum pots. Supplemental iron [2 mg/(kg.d)] was recommended from 15 d to 12 mo of age for both groups. At 12 mo of age, the group fed food cooked in iron pots had significantly better hematologic values than the group fed food cooked in aluminum pots. Differences included hemoglobin (116 +/- 16 vs. 103 +/- 20 g/L, P = 0.02), hematocrit (0.35 +/- 0.04 vs. 0.31 +/- 0.05, P = 0.005), mean corpuscular volume (72.1 +/- 10.4 vs. 62.7 +/- 11.1 fL, P = 0.005), free erythrocyte protoporphyrin (0.78 +/- 0.60 vs. 1.46 +/- 0.94 mol/L, P = 0.006) and serum ferritin (median 5 vs. 0 g/L, P = 0.001). No significant differences between groups were observed in serum iron concentration, total iron-binding capacity or transferrin saturation. Iron deficiency anemia (hemoglobin

PIP: A longitudinal study on iron nutritional status was carried out among 45 preterm, healthy infants 4-12 months of age from low-income families in Sao Paulo State, Brazil. The aim of the study was to determine whether cooking food in iron pots has the potential to prevent anemia in premature infants. 22 infants were randomly assigned to receive food cooked in iron pots, while food for the 23 controls was prepared in aluminum pots. Mothers of infants in both groups were instructed to administer 2 mg of ferrous sulfate starting at 15 days of age. At study onset, when infants were 4 months of age, there were no differences between these two groups in hematologic parameters. By 12 months of age, the children fed food from in iron pots had significantly more favorable hematologic values than control children. These differences included mean hemoglobin (116 vs. 103 g/L), hematocrit (0.35 vs. 0.31), mean corpuscular volume (72.1 vs. 62.7 fL), free erythrocyte protoporphyrin (0.78 vs. 1.46 mol/L), and median serum ferritin (5 vs. 0 g/L). There were no significant differences between groups in serum iron concentration, total iron-binding capacity, or transferrin saturation. Iron deficiency anemia (hemoglobin of 110 g/L or less) was found in 8 infants (36.4%) in the group fed food cooked in iron pots and 17 infants (73.9%) fed food prepared in aluminum pots. Although these findings indicate that the iron added to foods cooked in iron pots is bioavailable, the amount obtained through this process is insufficient to replenish depleted iron stores during the first year of life. This intervention merits consideration, however, as an adjunct to programs aimed at preventing iron deficiency in premature infants.

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