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Is the higher rate of parental child homicide in stepfamilies an effect of non-genetic relatedness？

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Current Zoology 2011年第3期57卷 253-259页

作者： Hans TEMRIN Johanna NORDLUND Mikael RYING Birgitta S. TULLBERG Department of Zoology Stockholm University SE- 106 91 Stockholm Sweden Department of Health Sciences Mid Sweden University SE-851 70 Sundsvall Sweden

In an evolutionary perspective individuals are expected to vary the degree of parental love and care in relation to the fitness value that a child represents. Hence, stepparents are expected to show less solicitude than genetically related parents, and this lack of genetic relatedness has been used to explain the higher frequencies of child abuse and homicide found in stepfamilies. However, other factors than non-genetic relatedness may cause this over-representation in stepfamilies. Here we use a 45-year data set of parental chiltl homicides in Sweden to test two hypotheses related to the higher incidence in stepfamilies： 1） adults in different types of family differ in their general disposition to use violence, and 2） parents are more likely to kill stepchildren than genetically related children. Of the 152 perpetrators in biparental families there was an overrepresentation of perpetrators in step- families （n=27） compared with the general population. We found support for the first hypothesis in that both general and violent crime rates were higher in stepfamilies, both in the general population and among perpetrators of child homicide. However, we found no support for the second hypothesis because of the 27 perpetrators in stepfamilies the perpetrator killed a genetically related child in 13 cases, a stepchild in 13 cases and both types of children in one case. Moreover, out of the 12 families where the perpetrator lived with both stepchildren and genetic children, there was no bias towards killing stepchildren. Thus, we found no evidence for an effect of non-genetic relatedness per se [Current Zoology 57 （3）： 253-259, 2011].

关键词： Cinderella effect Alternative explanations Characteristics of parents Previous criminality Violence

What Do We Really Know about Cellulose Biosynthesis in Higher Plants?

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Journal of Integrative Plant Biology 2010年第2期52卷 161-175页

作者： Gea Guerriero Johanna Fugelstad Vincent Bulone Division of Glycoscience School of BiotechnologyRoyal Institute of TechnologyAlbaNova University CenterSE-106 91 StockholmSweden

Cellulose biosynthesis is one of the most important biochemical processes in plant biology. Despite the considerable progress made during the last decade, numerous fundamental questions related to this key process in plant development are outstanding. Numerous models have been proposed through the years to explain the detailed molecular events of cellulose biosynthesis. Almost all models integrate solid experimental data with hypotheses on several of the steps involved in the process. Speculative models are most useful to stimulate further research investigations and bring new exciting ideas to the field. However, it is important to keep their hypothetical nature in mind and be aware of the risk that some undemonstrated hypotheses may progressively become admitted. In this review, we discuss the different steps required for cellulose formation and crystallization, and highlight the most important specific aspects that are supported by solid experimental data.

关键词： cell What Do We Really Know about Cellulose Biosynthesis in Higher Plants

Import Determinants of Organelle-Specific and Dual Targeting Peptides of Mitochondria and Chloroplasts in Arabidopsis thaliana

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Molecular Plant 2014年第1期7卷 121-136页

作者： Changrong Ge Erika Spanning Elzbieta Glaser Ake Wieslander Department of Biochemistry and Biophysics Center for Biomembrane Research Stockholm University SE-106 91 Stockholm Sweden Medical Inflammation Research Department of Medical Biochemistry and Biophysics Karolinska Institute SE-171 77 Stockholm Sweden

Most of the mitochondrial and chloroplastic proteins are synthesized in the cytosol as precursor proteins carrying an N-terminal targeting peptide （TP） directing them specifically to a correct organelle. However, there is a group of proteins that are dually targeted to mitochondria and chloroplasts using an ambiguous N-terminal dual targeting peptide （dTP）. Here, we have investigated pattern properties of import determinants of organelle-specific TPs and dTPs combining mathematical multivariate data analysis （MVDA） with in vitro organellar import studies. We have used large datasets of mitochondrial and chloroplastic proteins found in organellar proteomes as well as manually selected data sets of experimentally confirmed organelle-specific TPs and dTPs from Arabidopsis thaliana. Two classes of organelle-specific TPs could be distinguished by MVDA and potential patterns or periodicity in the amino acid sequence contributing to the separation were revealed, dTPs were found to have intermediate sequence features between the organelle-specific TPs. Interestingly, introducing positively charged residues to the dTPs showed clustering towards the mitochondrial TPs in silico and resulted in inhibition of chloroplast, but not mitochondrial import in in vitro organellar import studies. These findings suggest that positive charges in the N-terminal region of TPs may function as an ＇avoidance signal＇ for the chloroplast import.

关键词： dual targeting ambiguous targeting signal mitochondria chloroplast protein import partial least square discriminant analysis Arabidopsis thaliana.

Mysterious Waters at Metal Surfaces

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Journal of Materials Science & Technology 2010年第9期26卷 769-775页

作者： Jibiao Li Sheng longZhu Fuhui Wang State Key Laboratory for Corrosion and Protection Institute of Metal Research Chinese Academy of SciencesShenyang 110016 China Department of Physics Stockholm University AlbaNova University Centre SE-106 91 Stockholm Sweden

Molecular structures of adsorbed waters at metal surfaces are essential to understanding the widespread processes ranging from ice nucleation,to water involved catalytic surface reactions,to many phenomena of biological and astrochemical *** of providing a comprehensive literature survey,we focus in this review on detailed structural information,such as water orientations and occupation sites,of intact waters at low temperatures and ultrahigh vacuum conditions investigated by various surface *** progresses made in direct imaging the surface waters at high resolutions,as exemplified in a close-packed（***（111）） and an open metal surfaces（***（110）） supported waters,structural mysteries remain at diverse metal *** highlight experimental challenges and discuss structural mysteries in elucidating surface water structures at molecular levels.

关键词： Water monolayer Surface structure Transition metal surfaces

On the deterring effect of a butterfly＇s eyespot in juvenile and sub-adult chickens

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Current Zoology 2015年第4期61卷 749-757页

作者： Martin OLOFSSON Christer WIKLUND Anna FAVATI Department of Zoology Stockholm University SE-106 91 Stockholm Sweden School of Biology Indian Institute of Science Education and Research Thiruvananthapuram Thiruvananthapuram 695016 India

Circular patterns, or eyespots, are common anti-predator features in a variety of animals. Two defensive functions have been documented： large eyespots may intimidate predators, whereas smaller marginal eyespots may divert attacks. However, a given eyespot potentially serves both functions, possibly depending on the predator＇s size and/or experience. Naive predators are potentially more likely to misdirect their attacks towards eyespots; alternatively, their typically smaller size would make them more intimidated by the same eyespots. Here we test how juvenile and sub-adult naive chickens respond to a single eyespot on a butterfly＇s wing. We presented the birds with dead wall brown butterflies, Lasiommata megera, that had their apical eyespot visible or painted over. We assessed the birds＇ responses＇ by （i） scoring their intimidation reaction, （ii） whether they uttered alarm calls and, （iii） if they attacked the butterfly and where they targeted their attacks. Results show that both age categories received higher intimidation scores when offered a butterfly with a visible eyespot. Juveniles were more intimidated by the butterfly than the sub-adults： they received higher intimidation scores and were more prone to utter alarm calls. Moreover, only sub-adults at- tacked and did so by preferentially attacking the butterfly＇s anterior. We demonstrate an intimidating effect of the type of eyespot that has previously been shown only to divert attacks. We suggest that one and the same eyespot may serve two functions relative to different predators; however, further experiments are needed to disentangle the role of predator identity and its link to size, on- togeny and experience [Current Zoology 61 （4）： 749-757, 2015].

关键词： Predator-prey interactions Prey-attack behaviour Butterfly Bird Eyespot Ontogeny

DIFFERENT TYPES OF MICROFIBRILLATED CELLULOse AS FILLER MATERIALS IN POLYSODIUM ACRYLATE SUPERABSORBENTS

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Chinese Journal of Polymer Science 2011年第4期29卷 407-413页

作者： Mikael Larsson Qi Zhou Anette Larssona Department of Chemical and Biological Engineering Chalmers University of Technology 41296 Gothenburg Sweden Wallenberg Wood Science Center Royal Institute of Technology SE-100 44 Stockholm Sweden School of Biotechnology Royal Institute of Technology SE-106 91 Stockholm Sweden

Three types of microfibrillated cellulose （MFC） with differences in structure and surface charge were used at low concentration as filler materials in polysodium acrylate superabsorbents （SAPs）. The swelling of the composite hydrogels was determined in 0.9% NaCl solution as well as in deionized water. The shear modulus of the samples was determined through uniaxial compression analysis after synthesis and after swelling in 0.9% NaC1 solution. Furthermore, the ability to retain filler effects after washing was investigated. The results showed that all of the investigated MFCs had a strong reinforcing effect on the shear modulus after synthesis. The filler effect on swelling and on the associated shear modulus of swollen samples showed a more complicated dependence on structure and surface charge. Finally, it was found that the filler effects were reasonably retained after washing and subsequent drying. The results confirm that MFC holds great potential as a filler material in superabsorbent applications. Furthermore, the results provide some insight on how the structural properties and surface charge of MFC will affect gel properties depending on swelling conditions. This information should be useful in evaluating the use of different types of MFC in future applications.

关键词： SAP MFC Microfibrillated cellulose Polyacrylic acid Hydrogels.

Liquid water structure from X-ray absorption and emission, NMR shielding and X-ray diffraction

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Science China(Physics,Mechanics & Astronomy) 2019年第10期62卷 68-81页

作者： Iurii Zhovtobriukh Benedito J.C.Cabral Carmelo Corsaro Domenico Mallamace Lars G.M.Pettersson Department of Physics Stockholm UniversityAlbaNova University CenterStockholm SE-106 91Sweden University of Lisboa Faculty of SciencesBioISI-Biosysterns&Integrative Sciences InstituteLisboa 1749-016Portugal MI FT Department Messina UniversityMessina IT-98166Italy

Here we investigate to what extent X-ray absorption（XAS） and emission（XES） spectroscopy, the oxygen-oxygen radial distribution function and σ（1H） and σ(17O) NMR shielding can be represented by a common set of model structures of liquid water. This is done by using a Monte Carlo-based fitting technique which fits the spectra based on a library of ～1400 precomputed spectra and assigns weights to contributions from different model structures. These are then used to reweight the contributions from the structures in the library to reveal classes of structures that are over-or under-represented in the library. The goal is to include different experimental data sets which are sensitive to different aspects of liquid water structure and thus narrow down which types of structures must exist in the real liquid.

关键词： liquid water X-ray absorption X-ray emission NMR reverse Monte Carlo

Preparation of nano-sized Bi2Te3 thermoelectric material powders by cryogenic grinding

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Progress in Natural Science:Materials International 2012年第3期22卷 201-206页

作者： Xiaozong Chen a, Leifeng Liu b, Yuan Dong a, Lianjun Wang a, Lidong Chen c, Wan Jiang a, a State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, Donghua University, 2999 people of North Road, Shanghai 201620, PR China b Department of Materials and Environmental Chemistry, stockholm University, se-106 91 stockholm, Sweden c Shanghai Institute of Ceramics, Chinese Academy of Sciences, 1295 Dingxi Road, Shanghai 200050, PR China State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua University 2999 people of North Road Shanghai 201620 PR China Department of Materials and Environmental Chemistry Stockholm University SE-106 91 Stockholm Sweden Shanghai Institute of Ceramics Chinese Academy of Sciences 1295 Dingxi Road Shanghai 200050 PR China

A novel method for rapid preparation of Bi2Te3 nano-sized powders with an average particle size of about 70 nm was developed. A starting powder mixture consisting of Bi2Te3 coarse particles of ～5 mm was ground using cryogenic grinding in the liquid nitrogen. For comparison, the conventional high-energy ball milling was used to prepare the Bi2Te3 nano-sized powders. Sintering properties of as-prepared powders was investigated by spark plasma sintering (SPS). The effects of the preparation procedure on the crystallinity, morphology and structure were examined by X-ray diffraction (XRD) and transmission electron microscopy (TEM). It was found that Bi2Te3 was not transformed into a non-equilibrium amorphous phase or decomposed during the cryogenic grinding process, and as-prepared nano-powders possessed excellent sinterability. This technique might also be applicable to other thermoelectric materials.

关键词： Thermoelectric (TE) material Cryogenic grinding Bi2Te3 Nanoparticles Two-step breaking model

Heterogeneous oxidation of cyclohexanone catalyzed by TS-1：Combined experimental and DFT studies

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催化学报 2015年第6期36卷 845-854页

作者： Changjiu Xia Long Ju Yi Zhao Hongyi Xu Bin Zhu Feifei Gao Min Lin Zhenyu Dai Xiaodong Zou Xingtian Shu Department of Materials and Environmental Chemistry Stockholm University SE-106 91 Stockholm Sweden State Key Laboratory of Catulytic Materials and Reaction Engineering Research Institute of Petroleum Processing SINOPEC Beijing100083 China

The reaction mechanism of the oxidation of cyclohexanone catalyzed by titanium silicate zeolite TS-1 using aqueous H 2 O 2 as the oxidant was investigated by combining density function theory (DFT) calculations with experimental studies. DFT calculations showed that H 2 O 2 was adsorbed and activated at the tetrahedral Ti sites. By taking into account the adsorption energy, molecular size, steric hindrance and structural information, a reaction mechanism of Baeyer-Villiger oxidation catalyzed by TS-1 that involves the activation of H 2 O 2 was proposed. Experimental studies showed that the major products of cyclohexanone oxidation by H 2 O 2 catalyzed by a hollow TS-1 zeolite were ɛ-carprolactone, 6-hydroxyhexanoic acid, and adipic acid. These products were analyzed by GC-MS and were in good agreement with the proposed mechanism. Our studies showed that the reaction mechanism on TS-1 zeolite was different from that on Sn-beta zeolite.

关键词： TS-1分子筛催化氧化密度泛函理论环己酮实验异质性 GC-MS分析过氧化氢