bluuebunny/crossref_metadata_2025 huggingface dataset:
The Fates of Spiracular Allostoses in Mammals
Authors: Bjerring Hans C.
Published: April 2010

The human temporal bone includes an upper and a lower allostotic component, which are referred to, respectively, as the pars squamosa and pars tympanica in the adult and as the os squamosum and os tympanicum in the fetus. The consensus is that the former is descended from a cheek bone and the latter from a jaw bone in piscine osleolepipods. However, no corroborating evidence supports this view. It is concluded here that both these allostotic components of the human temporal bone derive from spiracular allostoses, except for the zygomatic process of the pars squamosa, this being a cheek allostosis that has been secondarily united with the squama. This is the first recognition of erstwhile spiracular allostoses in tetrapods. These conclusions challenge the widely accepted Reichert‐Gaupp theory as well as the oft‐alleged monophyletic status of the mammals and their derivation from therapsid reptiles.
A Quantitative, Comparative Study of Element Variations Found within the Range of Blood Cells from the Tropical Ascidian Phallusia philippinensis, using the Nuclear Microscope
Authors: Hogarth A. N. , Thong P. S. P. , Lane D. J. W. , Watt F.
Published: April 2010

The present study examines the concentrations of vanadium, bromine and sulphur contained within cryofixed/freeze‐dried blood cells of the ascidian Phallusia philippinensis. Elemental profiles of seven cell types were obtained using the National University of Singapore nuclear microscope, in order to ascertain the cell types predominantly involved in accumulation. Morula cells were found to contain the following mean values (in ppm dry weight); 7878 vanadium, 34484 bromine and 61078 sulphur. Signet ring cells contained 5191 vanadium, 23945 bromine and 15281 sulphur. Compartment cells had 606 vanadium, 20700 bromine and 24309 sulphur. Other less abundant cell types such as lymphocytes, macrogranular amoebocytes, carotenoid pigment cells and granular amoebocytes were also analysed and found to contain (in ppm) 4384, 6652, 2366 and 10246 vanadium, 19652, 15630, 5964 and 11735 bromine and 13289, 15309, 3106 and 42968 sulphur, respectively. Sulphur occurred in high levels in all cell types, which could indicate its involvement in the vanadium concentration process, while bromine, incorporated into complexes, may be utilised for anti‐fouling rather than as a deterrent to predators.
The Ontogeny of the Nephridial System of the Larval Amphioxus (Branchiostoma lanceolatum)
Authors: Stach Thomas , Eisler Klaus
Published: April 2010

Three developmental stages of Branchiostoma lanceolatum were examined by means of transmission electron microscopy. The development of the protonephridium‐like cyrtopodocyte from nearly undifferentiated (ento‐) mesodermal cells is demonstrated. The ultrastructure of Hatschek's nephridium in an early larval stage is described. The existence of a second filtralional barrier around the rod‐like microvilli of the cyrtopodocytes was confirmed. The mesodermal nephridium drains via an excretory canal which is possibly of ectodermal origin into the oral cavity. Cytotic vesicles in the canal cells suggest that the organ is functional in the earliest larval stages. The phylogenetic interpretation of the cyrtopodocyte is clarified as an autapomorphy of the acraniates derived from a podocyte with an apical cilium. The whole system is comparable to the pronephros of craniates and therefore represents a modified metanephridium.
Setal Structure and Chaetogenesis in Scolelepis squamata and Malacoceros fuliginosus (Spionidae, Annelida)
Authors: Hausen H. , Bartolomaeus T.
Published: April 2010

In Scolelepis squamata and Malacoceros fuliginosus two alternatingly arranged transverse rows of setae are found in each ramus. These are capillary setae in all thoracic setigers, whereas in abdominal setigers they may alternate with hooded hooks. In M. fuliginosus only the abdominal neuropodia bear hooded hooks, whereas in S. squamata these setae are present in both rami in the abdomen. Here every second seta (the capillary one) degenerates before its formation is complete, leading to a single row of hooded hooks. In the transverse rows new setae are formed in a medio‐lateral formative site in both species. Additionally in each ramus there exists one longitudinal row of capillaries which each possesses its own formative site. Ultrastructure and formation of the hooded hooks in S. squamata is very similar to that of hooded hooks in Capitellidae. The hood is preformed by a certain group of microvilli of the chaetoblast, which soon differentiates two layers of microvilli, raising an inner and an outer hood lamella. The hooded hooks and their arrangement are regarded as homologous characters in Spionidae and Capitellidae. This indicates a closer relationship of Spionidae with a taxon consisting of Capitellidae, Arenicolidae, Maldanidae, Oweniida, Terebellida, Sabellida, and Pogonophora.
Light Guides of the Escal Light Organs in Some Deep‐Sea Anglerfishes (Pisces; Ceratioidei)
Authors: Munk Ole
Published: April 2010

The paper deals with the microscopic structure of tubular light guides in escal appendages of three deep‐sea anglerfishes, Oneirodes eschrichti, Phyllorhinichthys micractis, and Linophryne coronata. The bases of the light guides are located oposite to an aperture in the lightproof cup enclosing the escal light gland. The light guides have an axial light‐transmitting core enclosed by a tubular wall with an opening or window through which light is emitted. The wall consists of a layer of reflecting cells, in two of the three species supplemented by an outer layer of pigmented cells. The window either has a terminal position or is located in the light guide wall near its closed end. A special annular window, situated beneath an inverted cone of reflecting cells, is present at the flattened tip of the light guide within the distal appendage of P. micractis. In one of the species studied (L. coronata) it appears likely that a sphincter of smooth muscle cells may regulate the transmission of light from the light gland to the light guides.
On the Anatomy of the Central Nervous System of Phyllodocidae (Polychaeta) and the Phylogeny of Phyllodocid Genera: a New Alternative
Authors: Orrhage Lars , Eibye‐Jacobsen Danny
Published: April 2010

A reinvestigation of the central nervous system of the Phyllodocidae appeared necessary as the existing literature proved insufficient for detailed comparisons with other polychaete families. Many earlier opinions turned out to be quite contradictory, especially as concerns the morphological value of the anterior end appendages. In the present paper the microanatomy of the brain and the anterior ventral cord, as well as the innervation of, inter alia, the cephalic appendages, the nuchal organs and the alimentary canal of Eulalia viridis (main object of study), Eumida sanguinea, Pterocirrus macroceros, Sige fusigera, Eteone picta, E. foliosa, Phyllodoce groenlandica, P. longipes, P. mucosa, Paranaitis wahlbergi, Notophyllum foliosum and Nereiphylla lutea are described. The results are summarized in schematic diagrams and compared with corresponding observations on other polychaete families. Thereby, some earlier opinions about the nature of the cephalic appendages of the Phyllodocidae are strengthened while others are rejected. Most significantly, it is concluded that the so‐called ventrolateral antennae of phyllodocids are homologous with the palps of other polychaetes and the median antenna found in certain genera is homologous with the nuchal papilla found in most other genera of the family. These partly new or revised characters and character states formed the basis for a reconsideration of earlier ideas about the phylogeny of the Phyllodocidae: a new alternative.
The Homology of Cortical Microtubules in Platyhelminth Spermatozoa: a Comparative Immunocytochemical Study of Acetylated Tubulin
Authors: Justine Jean‐Lou , Iomini Carlo , Raikova Olga I. , Mollaret Isabelle
Published: April 2010

Spermatozoa of certain acoels, a group of primitive Platyhelminthes, and spermatozoa of the most derived Platyhelminthes, the Cercomeridea (parasitic Platyhelminthes), show a general morphological resemblance in that they are long filiform cells with two incorporated axonemes and longitudinal cortical microtubules. A possible way to test the homology of these cortical microtubules in the different groups is to analyze the presence/absence of post‐translational modifications of tubulin. An indirect immunofluorescence study showed that the doublet microtubules of the sperm axonemes are labelled by an anti acetylated‐alpha‐tubulin antibody in all groups, irrespective of the axoneme pattern (9 + 0, 9 + 2 and non‐trepaxonematan 9 + “1” in various acoels, and trepaxonematan 9 + “1” of the temnocephalid Troglocaridicola sp., the digenean Echinostoma caproni and the monopisthocotylean monogenean Pseudodactylogyrus sp.). Significant differences are found in the sperm cortical microtubules: they are acetylated in the acoel Actinoposthia beklemischevi, but not in the digenean E. caproni and the temnocephalid Troglocaridicola sp. These results suggest that the sperm cortical microtubules of the acoels are not homologous with the morphologically similar elements found in the higher Platyhelminthes.
Ultrastructural Study of the Brain of a Typhloplanid Flatworm
Authors: Bedini Celina , Lanfranchi Alberto
Published: April 2010

The brain of Strongylostoma simplex shows the organization typical of the most evolutionary groups of free‐living plathelminths. Three types of neurons, two types of neurosecretory cells, and a certain number of glia‐like cells are present. Somato‐axonic synapses and axo‐dendritic contacts with a “spine apparatus”, like those described in vertebrates, have been identified. These two types of synapses have never been reported in other plathelminth brains. Local thickenings and dense bars attached to the presynaptic membrane are also observed, together with the paramembranous density common in many flatworm synapses.
Morphology of the Hagfish Inner Ear
Authors: Jørgensen J. M. , Shichiri M. , Geneser F. A.
Published: April 2010

The inner ear of five species of hagfishes was examined with different light and electron microscopical techniques. In all species, the labyrinth contains a single macula and two cristae, in a single semicircular canal. The macula consists of a horizontal, a middle vertical and a posterior horizontal component. Each component is covered by numerous round statoconia. The ring‐shaped cristae have very long kinocilia, but lack a proper cupula. The sensory epithelia show signs of regeneration, indicated by the presence of mitoses and apoptotic hair cells.
Interspecific Variation in Structural Organisation of the Spermatozoon in the Asian Bandicoot Rats, Bandicota Species (family Muridae)
Authors: Breed W. G.
Published: April 2010

The structural organisation of the spermatozoon from two species of bandicoot rats Bandicota bengalensis and Bandicota indica was investigated by light and electron microscopy together with the effect of incubation in Triton‐X 100 and sodium dodecyl sulphate. The sperm head of B. bengalensis is invariably falciform, has a uniform electron‐dense nucleus capped by an acrosome with a posteriolateral equatorial segment, a subacrosomal cytoskeleton with a large rostral perforatorium, and a sperm tail, attached to the lower concave surface of the sperm head, with typical coarse fibres and fibrous sheath. By contrast, the sperm head shapes of B. indica are generally conical or bulbous, the nucleus contains a few large vacuoles, the acrosome lacks an equatorial segment, no recognisable perforatorium occurs, and the sperm tail, which is attached basally, is very short with only modest development of coarse fibres and fibrous sheath. These results indicate that, within the genus Bandicota, huge interspecific differences in morphology of the spermatozoon have evolved. The spermatozoa of B. bengalensis are similar to those of Rattus and many other murids and thus presumably represent the ancestral condition, whereas those of B. indica (and B. savilei) are unlike spermatozoa from any other eutherian mammal so far described. © 1998 The Royal Swedish Academy of Sciences. Published by Elsevier Science Ltd. All rights reserved
Comparative Studies of Ovicell Anatomy and Reproductive Patterns inCribrilina annulataandCelleporella hyalina(Bryozoa: Cheilostomatida)
Authors: Ostrovsky Andrew N.
Published: April 2010

Investigations of the common boreal‐arctic cheilostomate bryozoansCribrilina annulataandCelleporella hyalinahave shown that the two species possess similar ovicell structures and reproductive patterns. Both species are characterized by frontal dwarf ovicellate zooids, that are female autozooidal polymorphs inC. hyalinaand simultaneous hermaphroditic autozooids inC. annulata. The latter species in addition has ovicellate autozooids of the usual type. Each ovicell is formed from a maternal zooid only, and its cavity is lined by the outer hemispherical fold (ooecium) and the distal zooidal wall. The coelomic cavity of the ooecium is separated from the body cavity of the maternal zooid by a transverse wall with simple pores. Each pore is closed by a cell plug, and the ooecia may be considered as kenozooids. Each oocyte is accompanied by a single nurse cell that degenerates after ovulation. The eggs are macrolecithal inC. annulataand microlecithal inC. hyalina, and the former species is a non‐placental brooder whereas the latter forms a placenta. Fertilization is precocious. Possible mechanisms of sperm entry as well as oviposition are discussed. The literature concerning ovicell structure and development in cheilostomates is analysed. It is proposed that the brood chamber of cribrimorphs evolved by a fusion of costae and a reduction of the daughter zooid in ancestral forms. © 1998 The Royal Swedish Academy of Sciences. Published by Elsevier Science Ltd. All rights reserved
Fine Structure of the Mature Plasmodium of Intoshia variabili (Phylum Orthonectida), a Parasite of the Platyhelminth Macrorhynchus crocea
Authors: Slyusarev George S. , Miller Donald M.
Published: April 2010

The fine structure of the mature plasmodia of Intoshia variabili, found in the kalyptorhynch flatworm Macrorhynchus crocea, was studied with transmission electron microscopy. As the Plasmodium matures it forms long finger‐like extensions inside the host. These extensions eventually take the place of the genital system of the host turbellarian. The mature Plasmodium is separated from the host tissues by a continuous membrane. The entire Plasmodium is surrounded by modified host cells, which are thin and overlapping. These cells also have a rather homogenous cytoplasm with limited endoplasmic reticulum. The surface of the Plasmodium is mostly smooth and has numerous small extensions. Within the cytoplasm of the Plasmodium, different stages of development of both males and females could be observed. The cytoplasm also contains numerous small nuclei with distinct nucleoli. Scattered throughout the cytoplasm, in addition to nuclei, are mitochondria, various granules, multivesiculate bodies with lamellar structures, and a large number of small vesicles. The nature of the formation of the Plasmodium is discussed. © 1998 The Royal Swedish Academy of Sciences. Published by Elsevier Science Ltd. All rights reserved
THE GULLIFORD LECTURE: Bullying or befriending? Children's responses to classmates with special needs
Authors: Frederickson Norah
Published: April 2010

Children with special educational needs are generally less accepted, more rejected and more likely to be victims of bullying than their typically developing classmates. However, they are sometimes treated more favourably than classmates, more like friends than acquaintances. In this article, based on her contribution to the Gulliford Lecture series, Norah Frederickson of University College London argues that attributional processes which appear central to the establishment of peer acceptance and supportive relationships are more likely to be triggered when a child's difficulties are severe or obvious, classmates are older and explanatory information is given to them. Schools are sometimes reluctant to discuss the special needs of a pupil with their classmates due to concerns about labelling. However, the literature on labelling suggests that such concerns have been exaggerated and that labels can sometimes serve a protective function. Norah Frederickson suggests that respectful, helping relationships between typically developing classmates and pupils with special needs are valued by young people, their parents and teachers, and can build to friendships within a context of positive opportunities for interaction.
Do public pensions matter for health and wellbeing among retired persons? Basic and income security pensions across 13 Western European countries
Authors: Esser Ingrid , Palme Joakim
Published: April 2010

Esser I, Palme J. Do public pensions matter for health and wellbeing among retired persons? Basic and income security pensions across 13 Western European countries

Int J Soc Welfare 2010: ••: ••–••© 2010 The Author(s), Journal compilation © 2010 Blackwell Publishing Ltd and International Journal of Social Welfare.

Mortality rates suggest that elderly people in the advanced welfare democracies have experienced dramatically improved health over the past decades. This study examined the importance of public pensions for self‐reported health and wellbeing among retired persons in 13 Organisation for Economic Cooperation and Development countries in 2002–2005. New public pension data make it possible to distinguish between two qualities of pension systems: ‘basic security’ for those who have no or a short work history, and ‘income security’ for those with a more extensive contribution record. For enhanced cross‐national comparison, relative measures of ill‐health and wellbeing were constructed to account for cultural bias in responses to survey questions and heterogeneity among countries in the general level of population health. Overall, better health is found in countries with more generous pensions, although the results are gendered; for women's health, high basic security of the pension system appears to be particularly important. Women's wellbeing also tends to be more dependent on the quality of basic security.
Should complete blood count be part of the evaluation of febrile infants aged ≤2 months?
Authors: Bilavsky Efraim , Yarden‐Bilavsky Havatzelet , Amir Jacob , Ashkenazi Shai
Published: April 2010

Objective:  To determine the utility and importance of total white blood cell count (WBC) and absolute neutrophil count (ANC) as markers of serious bacterial infection (SBI) in hospitalized febrile infants aged ≤2 months.

Patients and methods:  Data on WBC and ANC were collected prospectively for all infants aged ≤2 months who were hospitalized for fever at our centre. The patients were divided into two groups by the presence or absence of SBI.

Results:  A total of 1257 infants met the inclusion criteria, of whom 134 (10.7%) had a SBI. The area under the ROC curve was 0.73 (95% CI: 0.67–0.78) for ANC, 0.70 (95% CI: 0.65–0.76) for %ANC and 0.69 (95% CI: 0.61–0.73) for WBC. The independent contribution of these three tests in reducing the number of missed cases of SBI was significant.

Conclusion:  Complete blood cell count should remain as part of the routine laboratory assessment in this age group as it is reducing the number of missing infants with SBI. Of the three parameters, ANC and %ANC serve as better diagnostic markers of SBI than total WBC. However, more accurate tests such as C‐reactive protein and procalcitonin should also be part of the evaluation of febrile infants in these age group as they perform better than WBC or ANC for predicting SBI.
Neopuff T‐piece mask resuscitator: is mask leak related to watching the pressure dial?
Authors: Tracy MB , Klimek J , Shingde V , Hinder M , Maheshwari R , Tracy SK
Published: April 2010

Abstract Aim:  The aim of the study is to compare mask leak and delivered ventilation during Neopuff (NP) mask ventilation in two modes: (i) with NP pressure dial hidden and resuscitator watching chest wall (CW) rise with, (ii) CW movement hidden and resuscitator watching NP pressure dial.

Methods:  Thirty‐six participants gave mask ventilation to a modified manikin designed to measure mask leak and delivered ventilation for two minutes in each mode randomly assigned. Paired t‐tests were used to analyse differences in mean values. Linear regression was used to determine the association of mask leak with delivered ventilation.

Results:  Of 7277 inflations analysed, 3621 were observing chest wall mode (CWM) and 3656 observing NP mode (NPM). Mask leak was similar between the groups; 31.6% for CWM and 31.5% (p = 0.56) for NPM. There were no significant differences in airways pressures and expired tidal volumes (TVe) between modes. Mask leak was strongly associated with TVe (R = −0.86 p < 0.0001) and with peak inspiratory pressure (PIP) (R = −0.51 p < 0.0001). TVe was associated with PIP (R = 0.51 p < 0.0001).

Conclusion:  This study provides reassurance that NP mask leak is not greater when resuscitators watch the NP pressure dial. Mask leak is related to TVe. Mask ventilation training with manikins should include tidal volume measurements.
Sox proteins in melanocyte development and melanoma
Authors: Harris Melissa L. , Baxter Laura L. , Loftus Stacie K. , Pavan William J.
Published: April 2010

Over 10 years have passed since the first Sox gene was implicated in melanocyte development. Since then, we have discovered that SOX5, SOX9, SOX10 and SOX18 all participate as transcription factors that affect key melanocytic genes in both regulatory and modulatory fashions. Both SOX9 and SOX10 play major roles in the establishment and normal function of the melanocyte; SOX10 has been shown to heavily influence melanocyte development and SOX9 has been implicated in melanogenesis in the adult. Despite these advances, the precise cellular and molecular details of how these SOX proteins are regulated and interact during all stages of the melanocyte life cycle remain unknown. Improper regulation of SOX9 or SOX10 is also associated with cancerous transformation, and thus understanding the normal function of SOX proteins in the melanocyte will be key to revealing how these proteins contribute to melanoma.
Rigid irregular connections on ℙ1
Authors: Arinkin D.
Published: April 2010

Katz’s middle convolution algorithm provides a description of rigid connections on ℙ1with regular singularities. We extend the algorithm by adding the Fourier transform to it. The extended algorithm provides a description of rigid connections with arbitrary singularities.
A lower bound for Garsia’s entropy for certain Bernoulli convolutions
Authors: Hare Kevin G. , Sidorov Nikita
Published: April 2010

Let β∈(1,2) be a Pisot number and let Hβ denote Garsia’s entropy for the Bernoulli convolution associated with β. Garsia, in 1963, showed that Hβ<1 for any Pisot β. For the Pisot numbers which satisfy xm=xm−1+xm−2+⋯+x+1 (with m≥2), Garsia’s entropy has been evaluated with high precision by Alexander and Zagier for m=2 and later by Grabner, Kirschenhofer and Tichy for m≥3, and it proves to be close to 1. No other numerical values for Hβ are known. In the present paper we show that Hβ>0.81 for all Pisot β, and improve this lower bound for certain ranges of β. Our method is computational in nature.
A Study of Design Fixation, Its Mitigation and Perception in Engineering Design Faculty
Authors: Linsey J. S. , Tseng I. , Fu K. , Cagan J. , Wood K. L. , Schunn C.
Published: April 2010

The bridge between engineering design and cognitive science research is critical to understand the effectiveness of design methods as implemented by human designers. The study reported in this paper evaluates the effects of design fixation in a group of engineering design faculty, and also provides evidence for approaches to overcome design fixation. Three conditions are compared, a control, a fixation group whom were provided with an example solution, and a defixation group whom were also given materials to mitigate their design fixation. Measures include indicators of design fixation and participant perceptions. The study demonstrates that the engineering design faculty show statistically significant evidence of design fixation, but only partially perceive its effects. This study also indicates that design fixation can be mitigated. The group of participants in this study, due to their background in engineering design research and experience with student design teams, was expected to have more accurate perceptions or awareness of design fixation than the typical participant. Understanding the incongruities between participant perceptions and quantitative design outcomes are particularly of interest to researchers of design methods. For this study, clear evidence exists that designers, even those that study and teach design on a regular basis, do not know when they are being influenced or fixated by misleading or poor information.
Simultaneous Selective Disassembly and End-of-Life Decision Making for Multiple Products That Share Disassembly Operations
Authors: Behdad Sara , Kwak Minjung , Kim Harrison , Thurston Deborah
Published: April 2010

Environmental protection legislation, consumer interest in “green” products, a trend toward corporate responsibility and recognition of the potential profitability of salvaging operations, has resulted in increased interest in product take back. However, the cost effectiveness of product take-back operations is hampered by many factors, including the high cost of disassembly and a widely varying feedstock of dissimilar products. Two types of decisions must be made, how to carry out the disassembly process in the most efficient manner to “mine” the value-added that is still embedded in the product, and then how to best utilize that value-added once it is recovered. This paper presents a method for making those decisions. The concept of a transition matrix is integrated with mixed integer linear programming to determine the extent to which products should be disassembled and simultaneously determine the optimal end-of-life (EOL) strategy for each resultant component or subassembly. The main contribution of this paper is the simultaneous consideration of selective disassembly, multiple products, and the value added that remains in each component or subassembly. Shared disassembly operations and capacity limits are considered. An example using two cell phone products illustrates application of the model. The obtained results demonstrate the most economical level of disassembly for each cell phone and the best EOL options for each resultant module. In addition, the cell phone example shows that sharing disassembly operations between different products makes disassembly more cost effective compared with the case in which each product is disassembled separately.
Analytical and Experimental Tooth Contact Pattern of Large-Sized Spiral Bevel Gears in Cyclo-palloid System
Authors: Kawasaki Kazumasa , Tsuji Isamu
Published: April 2010

Demand for large-sized spiral bevel gears has increased in recent years and a trend expected to continue. The large-sized spiral bevel gears with equi-depth teeth are usually manufactured based on Klingelnberg cyclo-palloid system. In this paper, the tooth contact pattern of large-sized spiral bevel gears in this system are investigated analytically and experimentally. First, the tooth contact pattern and transmission errors of such gears are analyzed. The analysis method is based on simultaneous generations of tooth surface and simulations of meshing and contact. Next, the large-sized spiral bevel gears are manufactured and the tooth contact pattern of these gears is investigated experimentally. Moreover, the real tooth surfaces are measured using a coordinate measuring machine and the tooth flank form errors are detected using the measured coordinates. It is possible to analyze the tooth contact pattern of the spiral bevel gears with consideration of the tooth flank form errors expressing the errors as polynomial equations. Finally, the influence of alignment errors due to assembly on the tooth contact pattern is also investigated analytically and experimentally. These analyzed results were compared with experimental ones. As a result, the two results showed a good agreement.
Robust Optimization of the Loaded Contact Pattern in Hypoid Gears With Uncertain Misalignments
Authors: Gabiccini M. , Bracci A. , Guiggiani M.
Published: April 2010

This paper presents an automatic procedure to optimize the loaded tooth contact pattern of face-milled hypoid gears with misalignments varying within prescribed ranges. A two-step approach is proposed to solve the problem: in the first step, the pinion tooth microtopography is automatically modified to bring the perturbed contact patterns (as the assembly errors are varied within the tolerance limits) match a target area of the tooth while keeping them off the edges; in the second step, a subset of the machine-tool settings is identified to obtain the required topography modifications. Both steps are formulated and solved as unconstrained nonlinear optimization problems. While the general methodology is similar to the one recently proposed by the same authors for the optimization at nominal conditions, here, the robustness issues with respect to misalignment variations are considered and directly included in the optimization procedure: no a posteriori check for robustness is therefore required. Numerical tests show that nominally satisfactory and globally robust hypoid pairs can be designed by a direct process and within a unified framework, thus avoiding tiresome trial-and-error loops.
Dysregulated Humoral Immunity to Nontyphoidal
Salmonella
in HIV-Infected African Adults
Authors: MacLennan Calman A. , Gilchrist James J. , Gordon Melita A. , Cunningham Adam F. , Cobbold Mark , Goodall Margaret , Kingsley Robert A. , van Oosterhout Joep J. G. , Msefula Chisomo L. , Mandala Wilson L. , Leyton Denisse L. , Marshall Jennifer L. , Gondwe Esther N. , Bobat Saeeda , López-Macías Constantino , Doffinger Rainer , Henderson Ian R. , Zijlstra Eduard E. , Dougan Gordon , Drayson Mark T. , MacLennan Ian C. M. , Molyneux Malcolm E.
Published: April 2010

HIV and
Salmonella

HIV-positive individuals who are infected with nontyphoidal strains of
Salmonella enterica
often succumb to high morbidity and mortality. Why this is the case is unknown.

MacLennan
et al.

(p.
508
; see the Perspective by

Moir and Fauci

) have uncovered a dysregulated antibody response to
Salmonella
that is the likely culprit. Sera from HIV-infected individuals do a poor job of killing
S.
Typhimurium, despite surprisingly elevated antibody titers. Experiments showed that HIV-infected serum inhibited the power of normal serum to kill
Salmonella
. Inhibition was specific to antibodies against lipopolysaccharide (LPS), a component of the cell wall of
Salmonella
. Hence, HIV-infected sera was able to kill
Salmonella
strains lacking LPS, and removing LPS immunoglobulin G from infected sera permitted
Salmonella
killing. Thus, not only does HIV cause defects in cell-mediated immunity but it also seems to impair humoral immunity, with severe consequences for multiple infections.
Science Education and Literacy: Imperatives for the Developed and Developing World
Authors: Webb Paul
Published: April 2010

This article explores current language-based research aimed at promoting scientific literacy and examines issues of language use in schools, particularly where science teaching and learning take place in teachers’ and learners’ second language. Literature supporting the premise that promoting reading, writing, and talking while “doing science” plays a vital role in effective teaching and learning of the subject is highlighted. A wide range of studies suggest that, whether in homogenous or language-diverse settings, science educators can make a significant contribution to both understanding science and promoting literacy.
Assessing Literacy Across a Changing World
Authors: Schleicher Andreas
Published: April 2010

New literacy skills affect educational and labor-market outcomes and can be compared from country to country.
Asian Monsoon Failure and Megadrought During the Last Millennium
Authors: Cook Edward R. , Anchukaitis Kevin J. , Buckley Brendan M. , D’Arrigo Rosanne D. , Jacoby Gordon C. , Wright William E.
Published: April 2010

Of Monsoons and Megadroughts

The Asian monsoon is the weather system that has the greatest effect on the greatest number of people in the world. Naturally then, knowing better how climate change might affect the monsoon is tremendously important. One obstacle that prevents a better understanding of future behavior is a poor knowledge of its past.

Cook
et al.

(p.
486
; see the Perspective by

Wahl and Morrill

) help to fill this gap with a 700-year reconstruction of the monsoon from tree-ring data obtained throughout Asia. The reconstruction chronicles monsoon failures and megadroughts, as well as patterns of precipitation, and can thus be compared with other relevant climate records to allow links with sea-surface temperatures to be better understood.
Stoichiometry and Architecture of Active DNA Replication Machinery in
Escherichia coli
Authors: Reyes-Lamothe Rodrigo , Sherratt David J. , Leake Mark C.
Published: April 2010

Forking Replisomes

Replisomes are multiprotein machines that replicate DNA. Significant insight into how they work comes from in vitro studies, but how replisomes are organized in living cells has remained unclear.

Reyes-Lamothe
et al.

(p.
498
) have watched the replisome in living
Escherichia coli
cells using single-molecule fluorescence spectroscopy with millisecond time resolution. Cells expressing fluorescent derivatives of 10 different replisome components revealed both the stoichiometry and spatial distribution of the components at active replication forks in
Escherichia coli
. A similar technique could be used to study other molecular machines as they function.
People, Societies, and Landscapes
Authors: French Charles
Published: April 2010

Sophisticated geographical models are aiding archaeological research into how people have used and altered local landscapes.
Toward Understanding and Predicting Monsoon Patterns
Authors: Wahl Eugene R. , Morrill Carrie
Published: April 2010

A comprehensive atlas of past monsoon patterns will help scientists understand the causes of monsoon variability.
Escaping Attention
Authors: Grüter Thomas , Carbon Claus-Christian
Published: April 2010

Some cognitive disorders can be overlooked.
A Sense of Crisis as China Confronts Ailments of Affluence
Authors: Normile Dennis
Published: April 2010

As rates of behavior-related diseases rise, China's medical community looks for ways to change attitudes and advance preventive care.
Utility of a Commercial Nonstructural Protein 1 Antigen Capture Kit as a Dengue Virus Diagnostic Tool
Authors: Bessoff Kovi , Phoutrides Elena , Delorey Mark , Acosta Luz N. , Hunsperger Elizabeth
Published: April 2010

Annually, over 2.5 billion people are at risk for infection with dengue virus (DENV), while between 50 and 100 million people contract the infection. There is an urgent need for alternative diagnostic tools that can detect DENV during acute infection. Recent studies have shown that DENV nonstructural protein 1 (NS1) is detectable in the blood as early as the onset of symptoms and persists well into the convalescent phase of the infection. We evaluated the utility of the Bio-Rad Platelia DENV NS1 antigen capture kit in combination with real-time reverse transcriptase PCR (RT-PCR) and an IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA) for refining a new algorithm for the diagnosis of acute- or convalescent-phase DENV infection with a single clinical sample. We tested the Bio-Rad kit with three panels of sera. These panels were designed to evaluate the sensitivities of the NS1 kit for (i) early-convalescent-phase samples, (ii) acute-phase samples with false-negative PCR results, and (iii) IgM-negative convalescent-phase samples from patients with confirmed secondary DENV infections. Results show that NS1 can be detected in 22% of serum samples collected more than 10 days after the onset of illness and in 22% of samples that did not elicit an IgM response. Additionally, NS1 was detected in 37% of the tested acute-phase samples with false-negative PCR results, suggesting that NS1 detection may be valuable in increasing the sensitivity of current acute-phase diagnostics. These results will improve diagnosis with a single acute-phase or early-convalescent-phase sample for disease surveillance and clinical diagnosis.
Impact of
Pseudomonas aeruginosa
Genomic Instability on the Application of Typing Methods for Chronic Cystic Fibrosis Infections
Authors: Fothergill Joanne L. , White Judith , Foweraker Juliet E. , Walshaw Martin J. , Ledson Martin J. , Mahenthiralingam Eshwar , Winstanley Craig
Published: April 2010

The Liverpool epidemic strain (LES) of
Pseudomonas aeruginosa
is widespread among cystic fibrosis (CF) patients in the United Kingdom and has emerged recently in North America. In this study, we report the analysis of 24 “anomalous” CF isolates of
P. aeruginosa
that produced inconsistent results with regard to either pulsed-field gel electrophoresis (PFGE) or PCR tests for the LES. We used a new typing method, the ArrayTube genotyping system, to determine that of the 24 anomalous isolates tested, 13 were confirmed as the LES. LES isolates could not be clearly distinguished from non-LES isolates by two other commonly used genetic fingerprinting tests, randomly amplified polymorphic DNA (RAPD) analysis and BOX-PCR, and varied considerably in their carriage of LES genomic islands and prophages. The genomic instability of the LES suggests that identification of this emerging transmissible strain could be a challenging task, and it questions whether discrimination is always a desirable feature of bacterial typing methods in the context of chronic CF infections.
Evidence for a Second Genomic Island Conferring Multidrug Resistance in a Clonal Group of Strains of
Salmonella
enterica
Serovar Typhimurium and its Monophasic Variant Circulating in Italy, Denmark, and the United Kingdom
Authors: Lucarelli Claudia , Dionisi Anna Maria , Torpdahl Mia , Villa Laura , Graziani Caterina , Hopkins Katie , Threlfall John , Caprioli Alfredo , Luzzi Ida
Published: April 2010

During the 2000s, a new clonal group with resistances to ampicillin, streptomycin, sulfonamides, and tetracycline (ASSuT) emerged in Italy among strains of
Salmonella enterica
serovar Typhimurium and its monophasic variant,
Salmonella enterica
subspecies
enterica
serovar 4,[5],12:i:−. The PulseNet Europe database allowed us to identify ASSuT strains of both
S
. Typhimurium and its monophasic variant, isolated in Denmark and the United Kingdom, with the same or very closely related pulsed-field gel electrophoresis (PFGE) patterns as the Italian strains, suggesting that the ASSuT clonal group is circulating in different European countries. With the aim of analyzing the molecular basis of antibiotic resistance, resistance genes were identified and their localization was investigated in 66 ASSuT strains and, as controls, in 11 strains with different resistance patterns and PFGE profiles, belonging both to
S
. Typhimurium and to its monophasic variant, isolated from humans in Italy, Denmark, and the United Kingdom. All the ASSuT strains were positive for the following resistance genes:
bla
TEM-1
,
strA
-
strB
,
sul
2, and
tet
(B). A localization experiment demonstrated that the ASSuT resistance genes are chromosomally located. This study confirms that a multidrug-resistant clonal group, ASSuT, of
S
. Typhimurium and its monophasic variant has emerged and is circulating in Italy, Denmark, and the United Kingdom. Moreover, the results of this work demonstrate that the multidrug resistance in this clonal group of
Salmonella
strains is conferred by a new genomic island.
Respiratory Syncytial Virus-Mediated NF-κB p65 Phosphorylation at Serine 536 Is Dependent on RIG-I, TRAF6, and IKKβ
Authors: Yoboua Fabrice , Martel Alexis , Duval Annick , Mukawera Espérance , Grandvaux Nathalie
Published: April 2010

Respiratory syncytial virus (RSV) is the etiological agent of acute respiratory diseases, such as bronchiolitis and pneumonia. The exacerbated production of proinflammatory cytokines and chemokines in the airways in response to RSV is an important pillar in the development of these pathologies. As such, a keen understanding of the mechanisms that modulate the inflammatory response during RSV infection is of pivotal importance to developing effective treatment. The NF-κB transcription factor is a major regulator of proinflammatory cytokine and chemokine genes. However, RSV-mediated activation of NF-κB is far from characterized. We recently demonstrated that aside from the well-characterized IκBα phosphorylation and degradation, the phosphorylation of p65 at Ser536 is an essential event regulating the RSV-mediated NF-κB-dependent promoter transactivation. In the present study, using small interfering RNA and pharmacological inhibitors, we now demonstrate that RSV sensing by the RIG-I cytoplasmic receptor triggers a signaling cascade involving the MAVS and TRAF6 adaptors that ultimately leads to p65ser536 phosphorylation by the IKKβ kinase. In a previous study, we highlighted a critical role of the NOX2-containing NADPH oxidase enzyme as an upstream regulator of both the IκBαSer32 and p65Ser536 in human airway epithelial cells. Here, we demonstrate that inhibition of NOX2 significantly decreases IKKβ activation. Taken together, our data identify a new RIG-I/MAVS/TRAF6/IKKβ/p65Ser536 pathway placed under the control of NOX2, thus characterizing a novel regulatory pathway involved in NF-κB-driven proinflammatory response in the context of RSV infection.
TRIM5α Disrupts the Structure of Assembled HIV-1 Capsid Complexes
In Vitro
Authors: Black Lesa R. , Aiken Christopher
Published: April 2010

The host restriction factor TRIM5α provides intrinsic defense against retroviral infections in mammalian cells. TRIM5α blocks infection by targeting the viral capsid after entry but prior to completion of reverse transcription, but whether this interaction directly alters the structure of the viral capsid is unknown. A previous study reported that rhesus macaque TRIM5α protein stably associates with cylindrical complexes formed by assembly of recombinant HIV-1 CA-NC protein
in vitro
and that restriction leads to accelerated HIV-1 uncoating in target cells. To gain further insight into the mechanism of TRIM5α-dependent restriction, we examined the structural effects of TRIM5 proteins on preassembled CA-NC complexes by electron microscopy. Incubation of assembled complexes with lysate of cells expressing the restrictive rhesus TRIM5α protein resulted in marked disruption of the normal cylindrical structure of the complexes. In contrast, incubation with lysate of control cells or cells expressing comparable levels of the nonrestrictive human TRIM5α protein had little effect on the complexes. Incubation with lysate of cells expressing the TRIMCyp restriction factor also disrupted the cylinders. The effect of TRIMCyp was prevented by the addition of cyclosporine, which inhibits binding of TRIMCyp to the HIV-1 capsid. Thus, disruption of CA-NC cylinders by TRIM5α and TRIMCyp was correlated with the specificity of restriction. Collectively, these results suggest that TRIM5α-dependent restriction of HIV-1 infection results from structural perturbation of the viral capsid leading to aberrant HIV-1 uncoating in target cells.
Inhibition of Hepatitis B Virus Replication by MyD88 Involves Accelerated Degradation of Pregenomic RNA and Nuclear Retention of Pre-S/S RNAs
Authors: Li Jianhua , Lin Shanshan , Chen Qiying , Peng Lu , Zhai Jianwei , Liu Yinghui , Yuan Zhenghong
Published: April 2010

Myeloid differentiation primary response protein 88 (MyD88), which can be induced by alpha interferon (IFN-α), has an antiviral activity against the hepatitis B virus (HBV). The mechanism of this antiviral activity remains poorly understood. Here, we report that MyD88 inhibited HBV replication in HepG2.2.15 cells and in a mouse model. The knockdown of MyD88 expression weakened the IFN-α-induced inhibition of HBV replication. Furthermore, MyD88 posttranscriptionally reduced the levels of viral RNA. Remarkably, MyD88 accelerated the decay of viral pregenomic RNA in the cytoplasm. Mapping analysis showed that the RNA sequence located in the 5′-proximal region of the pregenomic RNA was critical for the decay. In addition, MyD88 inhibited the nuclear export of pre-S/S RNAs via the posttranscriptional regulatory element (PRE). The retained pre-S/S RNAs were shown to degrade in the nucleus. Finally, we found that MyD88 inhibited the expression of polypyrimidine tract-binding protein (PTB), a key nuclear export factor for PRE-containing RNA. Taken together, our results define a novel antiviral mechanism against HBV mediated by MyD88.
Quantifying the Early Immune Response and Adaptive Immune Response Kinetics in Mice Infected with Influenza A Virus
Authors: Miao Hongyu , Hollenbaugh Joseph A. , Zand Martin S. , Holden-Wiltse Jeanne , Mosmann Tim R. , Perelson Alan S. , Wu Hulin , Topham David J.
Published: April 2010

Seasonal and pandemic influenza A virus (IAV) continues to be a public health threat. However, we lack a detailed and quantitative understanding of the immune response kinetics to IAV infection and which biological parameters most strongly influence infection outcomes. To address these issues, we use modeling approaches combined with experimental data to quantitatively investigate the innate and adaptive immune responses to primary IAV infection. Mathematical models were developed to describe the dynamic interactions between target (epithelial) cells, influenza virus, cytotoxic T lymphocytes (CTLs), and virus-specific IgG and IgM. IAV and immune kinetic parameters were estimated by fitting models to a large data set obtained from primary H3N2 IAV infection of 340 mice. Prior to a detectable virus-specific immune response (before day 5), the estimated half-life of infected epithelial cells is ∼1.2 days, and the half-life of free infectious IAV is ∼4 h. During the adaptive immune response (after day 5), the average half-life of infected epithelial cells is ∼0.5 days, and the average half-life of free infectious virus is ∼1.8 min. During the adaptive phase, model fitting confirms that CD8+CTLs are crucial for limiting infected cells, while virus-specific IgM regulates free IAV levels. This may imply that CD4 T cells and class-switched IgG antibodies are more relevant for generating IAV-specific memory and preventing future infection via a more rapid secondary immune response. Also, simulation studies were performed to understand the relative contributions of biological parameters to IAV clearance. This study provides a basis to better understand and predict influenza virus immunity.