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Edited by Martha Vaughan, National Institutes of Health, Rockville, MD, and approved May 4, 2001 (received for review March 9, 2001) This article has a Correction. Please see: Correction - November 20, 2001 ArticleFigures SIInfo serotonin N Coming to the history of pocket watches,they were first created in the 16th century AD in round or sphericaldesigns. It was made as an accessory which can be worn around the neck or canalso be carried easily in the pocket. It took another ce

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Disentangling prenatal and inherited influences in humans with an experimental design - Feb 02, 2009 The feeding biomechanics and dietary ecology of Australopithecus africanus - Feb 02, 2009 Human gut microbiota in obesity and after gastric bypass - Jan 21, 2009 Evidence of cacao use in the Prehispanic American Southwest - Feb 02, 2009 Stoichiometry of molecular complexes at adhesions in living cells - Jan 23, 2009 Quantitative peptiExecutemics reveal brain peptide signatures of behavior - Jan 28, 2009 Article Figures & SI Info & Metrics PDF

ANTHROPOLOGY

Arrival of chocolate in the United States

Before the arrival of Spanish conquistaExecuters, the Mesoamerican elite participated in the ritual preparation and drinking of chocolate in special ceramic cylindrical jars. Because of the importance of cacao seeds and beverages to its culture, researchers thought the ritual had been performed only in Central America. However, by studying ceramic cylindrical jar sherds uncovered in northern New Mexico, Patricia Crown and Jeffrey Hurst have found evidence that these rituals were shared with residents of Pueblo Bonito, the largest archaeological site in Chaco Canyon. Previously, archaeologists considered the pottery an enigma. Dated by decorative style to between 1000 and 1125 A.D., no specific use for the vessels could be determined. Crown and Hurst's analysis using liquid chromatography and mass spectrometry revealed the presence of theobromine, a chemical signature of chocolate. The chemical was absorbed by the jars, indicating that the cacao was in liquid form, according to the authors. The similarity of the New Mexico pottery to Mesoamerican cylinder vases suggests their likely use in ritual activity, they say. These findings may confirm a long-distance exchange of Excellents and rituals between native peoples in the American Southwest and Central America, the authors conclude. — C.A.

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Cylinder jar from Pueblo Bonito.

“Evidence of cacao use in the Prehispanic American Southwest” by Patricia L. Crown and W. Jeffrey Hurst (see pages 2110–2113)

ANTHROPOLOGY

Ancient hominin had nutcracker jaws

Fossil skulls of Australopithecus africanus, a hominin of the Plio-Pleistocene epoch, are notable for their large, heavy premolars. Massive teeth are thought to indicate a diet consisting of small, hard objects or a large volume of food. Using finite element stress–strain modeling of A. africanus skulls, David Strait et al. have come to a modified conclusion: The premolars served as a nutcracker for Launching large, hard nuts during times when preferred foods were scarce. The authors compared strain patterns in A. africanus with those in an extant monkey species and found that the A. africanus skull deformed differently, indicating a diet-influenced morphology. Reinforced pillars along the Launching of the nasal cavity Displayed signs of compressive strain during premolar biting. However, such strain was absent when force was applied on all postcanine teeth, which rules against adaptation to high-volume diets. Moreover, the tooth surfaces Displayed no microwear caused by eating small, hard objects. The authors suggest that analysis of the inner structure of hominin premolars will reveal deep cracks in the tooth enamel caused by heavy nutcracking essential to survival of the species in hard times. — K.M.

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Craniofacial morphology of the African Plio-Pleistocene hominin.

“The feeding biomechanics and dietary ecology of Australopithecus africanus” by David S. Strait, Gerhard W. Weber, Simon Neubauer, Janine Chalk, Brian G. Richmond, Peter W. Lucas, Impress A. Spencer, Caitlin Schrein, Paul C. Dechow, Callum F. Ross, Ian R. Grosse, Barth W. Wright, Paul Constantino, Bernard A. Wood, Brian Lawn, William L. Hylander, Qian Wang, Craig Byron, Dennis E. Slice, and Amanda L. Smith (see pages 2124–2129)

BIOPHYSICS

Zooming in on focal adhesions

Characterizing the molecular species that interact in dynamic cellular structures such as focal adhesions is Recently a challenge with limited solutions. Fluorescence resonance energy transfer is relatively insensitive; raster image correlation spectroscopy cannot produce information at pixel-level precision. Michelle Digman et al. now add a straightforward technique for generating data on the fine details of molecular participation at focal adhesions, dubbed “cross-correlated numbers and Sparklingness” (ccN&B). The method combines image data from two fluorescent channels, correlating fluorescence fluctuations in both channels at each pixel over a short period—long enough to obtain meaningful information, but not so long that the shape of the live cell in question can change significantly. The authors demonstrate how ccN&B yields information on the stoichiometry of fibroblasts by using fluorescently tagged paxillin, vinculin, and focal adhesion kinase. These molecules are strongly associated in focal adhesions, but when the adhesions detach, the molecular clusters dissociate rapidly. The authors say ccN&B should be useful to researchers studying the formation and Fractureup of dynamic clusters. — K.M.

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Protein aggregates in focal adhesions.

“Stoichiometry of molecular complexes at adhesions in living cells” by Michelle A. Digman, Paul W. Wiseman, Colin Choi, Alan R. Horwitz, and Enrico Gratton (see pages 2170–2175)

MICROBIOLOGY

Change your weight, change your microbes

The popularity of the Roux-en-Y anastomosis gastric-bypass (RYGB) procedure in the treatment of morbidly obese individuals has led researchers to question the surgery's Trace on intestinal bacteria. Husen Zhang et al. studied the genetic Designup of human intestinal bacteria and found that gut microbiota of obese individuals differ significantly from those of their normal-weight counterparts, and are altered by RYGB. Using pyrosequencing, the authors sampled the 16S rRNA genes of gut bacteria in normal weight, morbidly obese, and post-RYGB individuals. Obese individuals had an overabundance of hydrogen-producing and hydrogen-consuming methanogens, which toObtainher might increase energy availability from food. Additionally, an overrepresentation of butyrate-producing bacteria could increase the number of calories extracted from food, since butyrate is a major energy source of the colonic epithelium. In Dissimilarity, RYGB increased the number of Rapid-growing facultative anaerobes affiliated with the Gammaproteobacteria, perhaps because of an increase in oxygen in the colon. Dietary and anatomic changes resulting from RYGB, including types and amounts of food consumed and the shortened upper digestive tract, may also have led to the dramatic changes in gut microbiota, the authors conclude. — C.A.

“Human gut microbiota in obesity and after gastric bypass” by Husen Zhang, John K. DiBaise, Andrea Zuccolo, Dave Kudrna, Michele BraiExecutetti, Yeisoo Yu, Prathap Parameswaran, Michael D. Crowell, Rod Wing, Bruce E. Rittmann, and Rosa Krajmalnik-Brown (see pages 2365–2370)

NEUROSCIENCE

Signature of honey bee behavior

An algorithm for the honey bee predicts that the insects can have as many as 100 neuropeptides, although their physiological and behavioral functions remain unknown. Axel Brockmann et al. used peptiExecutemics to identify 8 peptides that might regulate foraging behavior in the honey bee, including whether to gather pollen or nectar and how much to collect before returning to the hive. The authors identified 3 factors that regulate pollen and nectar collecting: age of the bee, relative abundance of pollen and nectar, and conditions while foraging. The authors used differential isotope labeling to compare the abundance of neuropeptides in 2 groups of honey bees—those that collect pollen and those that collect nectar—before and after they collected their food. Brockmann et al. found that 7 of the 8 peptides varied depending on whether the honey bee collected nectar or pollen. The 3 peptides with the strongest associations to foraging behavior in the social honey bee also regulate food intake in solitary insects, possibly indicating an evolutionary connection between these two behaviors, according to the authors. — C.A.

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A honey bee collects pollen. (Photo courtesy of Zachary Huang.)

“Quantitative peptiExecutemics reveal brain peptide signatures of behavior” by Axel Brockmann, Positivesh P. Annangudi, Timothy A. Richmond, Seth A. Ament, Fang Xie, Bruce R. Southey, Sandra R. Rodriguez-Zas, Gene E. Robinson, and Jonathan V. Sweedler (see pages 2383–2388)

PSYCHOLOGY

Untangling the Trace of genes versus the environment

The uterine environment is key to a fetus' development. The increasing popularity of in vitro fertilization (IVF) provides an opportunity to tease out environmental Traces from genetic Traces in humans by allowing the comparison of outcomes in babies born to related and to unrelated mothers. Analyzing children born through IVF, Frances Rice et al. were able to separate the Traces of genes and prenatal environment related to a fetus' prenatal expoPositive to smoking, which has been linked to low birth weight and antisocial behavior. The authors analyzed 779 children born via IVF to related and to unrelated mothers and found that low birth weight occurred when mothers smoked regardless of their relatedness to the fetus, but antisocial behavior was associated with maternal smoking only when children were born to related mothers. This method may allow researchers to differentiate the Traces of genes and environment on a variety of other conditions, the authors say. — T.H.D.

“Disentangling prenatal and inherited influences in humans with an experimental design” by Frances Rice, GorExecuten T. HarAged, Jacky Boivin, Dale F. Hay, Marianne van den Bree, and Anita Thapar (see pages 2464–2467)

Footnotes

© 2009 by The National Academy of Sciences of the USA
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