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We compare domestic architectural features in New England and the Maritime Peninsula to investigate the relationship between the adoption of horticulture and its relationship to social and settlement change during the Woodland Period. Horticulture was not practiced on the Maritime Peninsula until after European contact, despite cultural and environmental similarity to New England. In New England, horticulture has been implicated in profound social and settlement changes. However, aggregated villages, a unit typically investigated for evidence of social change, have proven elusive in the archaeological record. We compiled and analyzed a dataset of dwelling features instead of relying on identifiable villages. This novel quantitative approach uses dwelling feature shape and size as a proxy for social and settlement change, considering these changes at the scale of the house. We find that, during the Woodland Period, dwelling size was overall slightly larger in New England than on the Maritime Peninsula, but ranges heavily overlapped. After the introduction of horticulture, however, dwellings in New England grew in size overall and assumed bimodally distinct larger and smaller forms, which likely necessitated a restructuring of social and economic behavior. This pattern correlates maize horticulture with changes in social and economic lifestyle in Late Woodland New England.
Polymer-containing solutions used across research and industry are commonly exposed to mechanically harsh fluid processes, for example shear and extensional forces during flow through porous media or rapid microdispensing of biopharmaceutical molecules. These forces are strong enough to break the covalent bonds in the polymer backbone. As this scission phenomenon can change the functional and fluid-flow properties as well as introduce reactive radicals into the solution, it must be understood and controlled. Experiments and models to date have only provided partial or qualitative insights into this behaviour. Here we build a link between the molecular-scale degradation models and the macroscale laminar flow of dilute solutions in any given geometry. A free-draining bead–rod model is used to investigate rupture events at the molecular scale. It is shown by uniaxial extension simulations of an ensemble of chains that scission can be conveniently described at the macroscopic scale as a first-order reaction whose rate is a function of the conformation tensor of the macromolecules and the velocity gradient of the flow. This approach is implemented in the finite volume code OpenFOAM by elaborating an appropriate constitutive equation for the conformation tensor. The macroscopic model is run and analysed for ultra-dilute solutions of poly(methyl methacrylate) in ethyl acetate and polyethylene oxide in water, using the geometry of an abrupt contraction flow and neglecting any viscoelastic effect. This multiscale approach bridges the gap between phenomenological observations of mechanically induced chemical degradation in large-scale applications and the rich field of molecular-scale models of macromolecules under flow.
Concerns have been raised about the potential adverse effects on reproductive health in farm animals, humans, and wildlife species from a range of environmental chemicals that disrupt normal hormonal actions. The alkylphenol polyethoxylates are non-ionic surfactants used in the manufacture of detergents, paints and herbicides. During sewage treatment, these compounds are broken down to short chain alkylphenol polyethoxylates, alkylphenol carboxylic acids and alkylphenols which bioaccumulate in the lipid of living organisms. The estrogenic nature of one of these compounds - octylphenol has been clearly demonstrated in cell culture, in a recombinant yeast screen with human estrogen receptor?and in animal studies. It is proposed that these endocrine disrupting compounds influence male adult reproductive potential by disrupting the development of the hypothalamic-pituitary-testicular axis during fetal life. We have recently identified that exposure to octylphenol for the second half of gestation decreases circulating concentrations of FSH during fetal life and the number of Sertoli cells of the testis and testis size at birth in comparison to control animals (Sweeney et al., 2000). However, the testes size, % interstitial space, semen volume, semen concentration and % live semen was similar in both treatment groups in the adult. In contrast animals exposed to octylphenol from birth to weaning (16 weeks of age) had a significantly greater number of primary and secondary abnormalities in comparison to controls and animals exposed to octylphenol for the second half of gestation. A number of the animals exposed to octylphenol from birth to weaning exhibited augmented sexual behaviour, while those exposed to octylphenol for the second half of pregnancy showed a suppression of sexual behaviour. The current data suggests the physiological effect of exposure to octylphenol is dependant on the time and duration of exposure. This has major implications for the determination of universal end-point measurements to assess exposure to endocrine disrupting compounds.
This observational study aims to investigate the microbiological quality of commercially prepared lightly cooked foods with a major component of food of animal origin and collected as would be served to a consumer. A total of 356 samples were collected from catering (92%), retail (7%) or producers (1%) and all were independent of known incidents of foodborne illness. Using standard methods, all samples were tested for: the presence of Campylobacter spp. and Salmonella spp. and enumerated for levels of, Bacillus spp. including B. cereus, Clostridium perfringens, Listeria spp. including L. monocytogenes, Staphylococcus aureus, Escherichia coli, Enterobacteriacea and aerobic colony count (ACC). Results were interpreted as unsatisfactory, borderline or satisfactory according to the Health Protection Agency guidelines for assessing the microbiological safety of ready-to-eat foods placed on the market. Amongst all samples, 70% were classified as satisfactory, 18% were borderline and 12% were of unsatisfactory microbiological quality. Amongst the unsatisfactory samples, six (2%) were potentially injurious to health due to the presence of: Salmonella spp. (one duck breast); Campylobacter spp. (two duck breast and one chicken liver pâté); L. monocytogenes at 4·3 × 103 cfu (colony-forming units)/g (one duck confit with foie gras ballotin) and C. perfringens at 2·5 × 105 cfu/g (one chicken liver pâté). The remaining unsatisfactory samples were due to high levels of indicator E. coli, Enterobacteriaceae or ACC.
The purpose of this study was to investigate the microbiological quality of liver pâté. During 2012–13, a total of 870 samples, unrelated to the investigation of food-poisoning outbreaks, were collected either at retail (46%), catering (53%) or the point of manufacture (1%) and were tested using standard methods to detect Salmonella spp. or Campylobacter spp., and to enumerate for Listeria spp., including Listeria monocytogenes, Clostridium perfringens, coagulase-positive staphylococci including Staphylococcus aureus, Bacillus spp., including Bacillus cereus, Escherichia coli, Enterobacteriaceae, and aerobic colony counts (ACCs). Seventy-three percent of samples were of satisfactory microbiological quality, 18% were borderline and 9% unsatisfactory. Salmonella spp. or Campylobacter spp. was not recovered from any sample. The most common causes of unsatisfactory results were elevated ACCs (6% of the samples) and high Enterobacteriaceae counts (4% of samples). The remaining unsatisfactory results were due to elevated counts of: E. coli (three samples); B. cereus (one sample at 2·6 × 105 cfu/g); or L. monocytogenes (one sample at 2·9 × 103 cfu/g). Pâté from retail was less likely to be contaminated with L. monocytogenes than samples collected from catering and samples from supermarkets were of significantly better microbiological quality than those from catering establishments.
The study of supernovae (SNe) and their environments in host galaxies at the highest possible angular resolution in a number of wavelength regimes is providing vital clues to the nature of their progenitor stars. We are observing SNe in the radio using the Very Large Array (VLA) and VLBI, in the X-rays with Chandra, and in the optical at the subarcsecond resolution of HST.
The δ Scuti stars are pulsating variables located in the lower part of the Cepheid instability strip with spectral types from A2 to F0 on the main sequence, and from A3 to F5 at luminosity class III. These variables show short periods (< 0.3day) and luminosity amplitudes ranging from a few thousandths of a magnitude to several tenths. Over the last few years, significant progress has been made in the detection of pulsating modes in the framework of the multisite campaigns, e.g. STACC (Frandsen et al. 1996), DSN (Breger et al. 1998), STEPHI (Michel et al. 2000). For the 1998 STEPHI IX photometry campaign, the δ Scuti star V534 Tau of the Pleiades cluster (see Table 1) was monitored during a three week, three continent run. Preliminary results are reported here.
Some results of the photometry multi-site observations of two δ Scuti stars, V624 Tau and HD 23194, are presented. The observations were carried out in the framework of a STEPHI network in 1999. We collected 343 hours of useful data and detected seven frequencies in V624 Tau and two frequencies in HD 23194.
Abnormal brain connectivity or network dysfunction has been suggested as a paradigm to understand several psychiatric disorders. We here review the use of novel meta-analytic approaches in neuroscience that go beyond a summary description of existing results by applying network analysis methods to previously published studies and/or publicly accessible databases. We define this strategy of combining connectivity with other brain characteristics as ‘meta-connectomics’. For example, we show how network analysis of task-based neuroimaging studies has been used to infer functional co-activation from primary data on regional activations. This approach has been able to relate cognition to functional network topology, demonstrating that the brain is composed of cognitively specialized functional subnetworks or modules, linked by a rich club of cognitively generalized regions that mediate many inter-modular connections. Another major application of meta-connectomics has been efforts to link meta-analytic maps of disorder-related abnormalities or MRI ‘lesions’ to the complex topology of the normative connectome. This work has highlighted the general importance of network hubs as hotspots for concentration of cortical grey-matter deficits in schizophrenia, Alzheimer's disease and other disorders. Finally, we show how by incorporating cellular and transcriptional data on individual nodes with network models of the connectome, studies have begun to elucidate the microscopic mechanisms underpinning the macroscopic organization of whole-brain networks. We argue that meta-connectomics is an exciting field, providing robust and integrative insights into brain organization that will likely play an important future role in consolidating network models of psychiatric disorders.
Young children raised in institutions are exposed to extreme psychosocial deprivation that is associated with elevated risk for psychopathology and other adverse developmental outcomes. The prevalence of attention deficit hyperactivity disorder (ADHD) is particularly high in previously institutionalized children, yet the mechanisms underlying this association are poorly understood. We investigated whether deficits in executive functioning (EF) explain the link between institutionalization and ADHD.
A sample of 136 children (aged 6–30 months) was recruited from institutions in Bucharest, Romania, and 72 never institutionalized community children matched for age and gender were recruited through general practitioners’ offices. At 8 years of age, children's performance on a number of EF components (working memory, response inhibition and planning) was evaluated. Teachers completed the Health and Behavior Questionnaire, which assesses two core features of ADHD, inattention and impulsivity.
Children with history of institutionalization had higher inattention and impulsivity than community controls, and exhibited worse performance on working memory, response inhibition and planning tasks. Lower performances on working memory and response inhibition, but not planning, partially mediated the association between early institutionalization and inattention and impulsivity symptom scales at age 8 years.
Institutionalization was associated with decreased EF performance and increased ADHD symptoms. Deficits in working memory and response inhibition were specific mechanisms leading to ADHD in previously institutionalized children. These findings suggest that interventions that foster the development of EF might reduce risk for psychiatric problems in children exposed to early deprivation.
The notion of creating artificial vision using visual prostheses has been
well represented though science fiction literature and films. When we think
of retinal prostheses, we immediately think of fictional characters like The
Terminator scanning across a bar to assess patrons for appropriately fitting
clothing, or Star Trek’s Geordi La Forge with his VISOR, a visual
instrument and sensory organ replacement placed across his eyes and attached
into his temples to provide him with vision. Such devices are no longer
farfetched. In the past 20 years, significant research has been undertaken
across the globe in the race for a “Bionic Eye”. Advances in
Bionic Eye research have come from improvements in the design and
fabrication of multielectrode arrays (MEAs) for medical applications. MEAs
are already commonplace in medicine with use in applications such as the
cochlear device, cardiac pacemakers, and deep brain stimulators where
interfacing with neuronal cell populations is required.
The use of MEAs for vision prostheses is currently of significant interest.
For the most part, retinal prostheses have dominated the research landscape
owing to the ease of access and direct contact to the retinal ganglion nerve
cells. However, MEAs are also in use for direct stimulation into the optic
nerve . Retinal prostheses bypass the damaged photoreceptor cells within
the retina and instead replace the degenerate retina with electrical
stimulation to the nerve cells. Using electrical stimulation, stimulated
retinal ganglion cells have been shown to elicit a percept in the form of a
phosphene in blind patients [2–6]. Accordingly, the two diseases
commonly linked to the justification for Bionic Eye research are age-related
macular degeneration (AMD) and retinitis pigmentosa (RP), diseases which
lead to progressive loss of photoreceptor cells and diseases where the
patient has had previous vision and thus exhibits prior visual-brain
pathways. At present, there has been no reliable cure for any of the retinal
diseases that target the photoreceptor cells, and thus the development of
prosthetic devices is a viable clinical treatment option [7–9].
Intracranial volume (ICV) has been proposed as a measure of maximum lifetime brain size. Accurate ICV measures require neuroimaging which is not always feasible for epidemiologic investigations. We examined head circumference as a useful surrogate for ICV in older adults.
99 older adults underwent Magnetic Resonance Imaging (MRI). ICV was measured by Statistical Parametric Mapping 8 (SPM8) software or Functional MRI of the Brain Software Library (FSL) extraction with manual editing, typically considered the gold standard. Head circumferences were determined using standardized tape measurement. We examined estimated correlation coefficients between head circumference and the two MRI-based ICV measurements.
Head circumference and ICV by SPM8 were moderately correlated (overall r = 0.73, men r = 0.67, women r = 0.63). Head circumference and ICV by FSL were also moderately correlated (overall r = 0.69, men r = 0.63, women r = 0.49).
Head circumference measurement was strongly correlated with MRI-derived ICV. Our study presents a simple method to approximate ICV among older patients, which may prove useful as a surrogate for cognitive reserve in large scale epidemiologic studies of cognitive outcomes. This study also suggests the stability of head circumference correlation with ICV throughout the lifespan.
A reassortant swine-origin A(H3N2) virus (A/swine/BinhDuong/03-9/2010) was detected through swine surveillance programmes in southern Vietnam in 2010. This virus contains haemagglutinin and neuraminidase genes from a human A(H3N2) virus circulating around 2004–2006, and the internal genes from triple-reassortant swine influenza A viruses (IAVs). To assess population susceptibility to this virus we measured haemagglutination inhibiting (HI) titres to A/swine/BinhDuong/03-9/2010 and to seasonal A/Perth/16/2009 for 947 sera collected from urban and rural Vietnamese people during 2011–2012. Seroprevalence (HI ⩾ 40) was high and similar for both viruses, with 62·6% [95% confidence interval (CI) 59·4–65·7] against A/Perth/16/2009 and 54·6% (95% CI 51·4–57·8%) against A/swine/BinhDuong/03-9/2010, and no significant differences between urban and rural participants. Children aged <5 years lacked antibodies to the swine origin H3 virus despite high seroprevalence for A/Perth/16/2009. These results reveal vulnerability to infection to this contemporary swine IAV in children aged <5 years; however, cross-reactive immunity in adults would likely limit epidemic emergence potential.
The effects of plerocercoids of the cestode Triaenophorus nodulosus infecting the livers of native Eurasian perch Perca fluviatilis and non-native pumpkinseed Lepomis gibbosus was investigated in 17 sites along the Moselle watershed. With a single exception, infected individuals were not observed in the main channel whether or not northern pike Esox lucius, a final host, was present. In ponds where the pike was present, the prevalence of T. nodulosus averaged 86% in Eurasian perch and 15% in pumpkinseed. The parasite was not present at all in ponds when pike were absent. Parasite load, hepatosomatic index (HSI), gonadosomatic index (GSI) and body condition index (CI) were compared between hosts in one site where parasite prevalence and fish abundance was highest. HSI in infected perch was significantly higher than in uninfected perch, whereas no differences in HSI were detected between infected and uninfected pumpkinseed. While perch were more frequently infected and had a greater average parasite load than pumpkinseed, there were no significant differences in either indicator between the two species. Furthermore, no significant differences in GSI or CI were observed between infected and uninfected fish in either species, by either gender or maturity stage. We hypothesize that pumpkinseed is more resistant to the parasite or less likely to feed upon infected copepods than perch.