Chasse of Champagnat, rear view, main plaque: lion of Mark; foliate decoration with fantasic beasts with human head; ox of Luke; roof plaque: angel, foliate decoration, eagle of John

4 7/8 in.x 7 7/16 in.x 3 11/32 in.; copper, engraved and gilt; champlevé ename on wood core

Numerical modeling of 11.1 T MRI of a human head using MoM/FDTD methods

In a recent study, severe distortions in the proton images of an excised, fixed, human brain in an 11.1 Tesla/40 cm MR instrument have been observed, and the effect modeled on phantom images using a finite difference time domain (FDTD) model. in the present study, we extend these simulations to that of a complete human head, employing a hybrid FDTD and method of moments (MoM) approach, which provides a validated method for simulating biological samples in coil structures. The effect of fixative on the image distortions is explored. importantly, temperature distributions within the head are also simulated using a bioheat method based on parameters derived from the electromagnetic simulations. The MoM/FDTD simulations confirm that the transverse magnetic field (B,) from a ReCav resonator exhibits good homogeneity in air but strong inhomogeneity when loaded with the head with or without fixative. The fixative serves to increase the distortions, but they are still significant for the in vivo simulations. The simulated signal intensity (SI) distribution within the sample confirm the distortions in the experimental images are caused by the complex interactions of the incident electromagnetic fields with tissue, which is heterogeneous in terms of conductivity and permittivity. The temperature distribution is likewise heterogeneous, raising concerns regarding hot spot generation in the sample that may exceed acceptable levels in future in vivo studies. As human imaging at 11.1 T is some time away, simulations are important in terms of predicting potential safety issues as well as evaluating practical concerns about the quality of images. Simulation on a whole human head at 11.1 T implies the wave behavior presents significant engineering challenges for ultra-high-field (UHF) MRI. Novel strategies will have to be employed in imaging technique and resonator design for UHF MRI to achieve the theoretical signal-to-noise ratio (SNR) improvements it offers over lower field systems. (C) 2005 Wiley Periodicals, Inc.

Transmission ratio distortion in the human body louse, Pediculus humanus (Insecta : Phthiraptera)

We studied inheritance at three microsatellite loci in eight F-1 and two F-2 families of the body (clothes) louse of humans, Pediculus humanus. The alleles of heterozygous female-parents were always inherited in a Mendelian fashion in these families. Alleles from heterozygous male-parents, however, were inherited in two different ways: (i) in a Mendelian fashion and (ii) in a non-Mendelian fashion, where males passed to their offspring only one of their two alleles, that is, 100% nonrandom transmission. In male body lice, where there was non-Mendelian inheritance, the paternally inherited set of alleles was eliminated. We interpret this pattern of inheritance as evidence for extreme transmission ratio distortion of paternal alleles in this species.

Prevalence of nits and lice in sampls of cut hair from floors of barbershop and beauty parlors in Belo Horizonte, Minas Gerais state, Brazil

A louse survey based on samples of cut hair collected from floors of barbershops and beauty parlors was conducted in Belo Horizonte, Minas Gerais State, Brazil, from October 1984 to April 1985, as an alternative way to determine the prevalence of pediculosis capitis in the population. Of 475 samples examined for nits, nymphs, or adults of Pediculus capitis, 140 were infested (29.5%). A total of 58 lice and 3.553 nits were found in 33.632.9 g of hair collected, giving a ratio of 0.10 nit/g. Almost 29% of the nits were viable and capable of being transmitted after hatching. There was significant difference among the infestation rates by socioeconomic levels, and samples from barbershops with male customers were the most infested. based upon the number of haircuts in each sample, we estimated that 5 or 6% of the population might be infested by this species.

Pediculose capitis: prevalência em escolares da Rede Municipal Pública de Belo Horizonte, Minas Gerais, Brasil

During 1985, 50,356 children and adolecents from 105 public schools of Belo Horizonte, Minas Gerais State were questioned about or examined for head lice (Pediculus capitis). The mean prevalence of pediculosis, obtainde from the questionnaires and sometimes confirmed by head inspections, was 7.7% or else 10.2% when adjusted to 38,311 respondents. Current and past infestations combined - within a period of three months before survey - revealed a total prevalence of 57.4%. Significant differences were observed among socioeconomic levels, and grades of school age. The more prevalent categories among the factors studied were: sex - femal: 9.2% (P<0.001); ethnic group - white: 10.0% (P<0.001); hair length - long: 9.5% (P<0.05); year age-group - 1-5 years: 19.2% (P<0.001), with a peak in the 5th year (21.3%).

Potential role of head lice, Pediculus humanus capitis, as vectors of Rickettsia prowazekii

Since the pioneering work of Charles Nicolle in 1909 [see Gross (1996) Proc Natl Acad Sci USA 93:10539-10540] most medical officers and scientists have assumed that body lice are the sole vectors of Rickettsia prowazekii, the aetiological agent of louse-borne epidemic typhus (LBET). Here we review the evidence for the axiom that head lice are not involved in epidemics of LBET. Laboratory experiments demonstrate the ability of head lice to transmit R. prowazekii, but evidence for this in the field has not been reported. However, the assumption that head lice do not transmit R. prowazekii has meant that head lice have not been examined for R. prowazekii during epidemics of LBET. The strong association between obvious (high) infestations of body lice and LBET has contributed to this perception, but this association does not preclude head lice as vectors of R. prowazekii. Indeed, where the prevalence and intensity of body louse infections may be high (e.g. during epidemics of LBET), the prevalence and intensity of head louse infestations is generally high as well. This review of the epidemiology of head louse and body louse infestations, and of LBET, indicates that head lice are potential vectors of R. prowazekii in the field. Simple observations in the field would reveal whether or not head lice are natural vectors of this major human pathogen.

A Simple and Efficient Device for Demonstrating Cross-sectional Anatomy of the Head

Described in this article is a novel device that facilitates study of the cross-sectional anatomy of the human head. In designing our device, we aimed to protect sections of the head from the destructive action of handling during anatomy laboratory while also ensuring excellent visualization of the anatomic structures. We used an electric saw to create 15-mm sections of three cadaver heads in the three traditional anatomic planes and inserted each section into a thin, perforated display box made of transparent acrylic material. The thin display boxes with head sections are kept in anatomical order in a larger transparent acrylic storage box containing formaldehyde solution, which preserves the specimens but also permits direct observation of the structures and their anatomic relationships to each other. This box-within-box design allows students to easily view sections of a head in its anatomical position as well as to examine internal structures by manipulating individual display boxes without altering the integrity of the preparations. This methodology for demonstrating cross-section anatomy allows efficient use of cadaveric material and technician time while also giving learners the best possible handling and visualization of complex anatomic structures. Our approach to teaching cross-sectional anatomy of the head can be applied to any part of human body, and the value of our device design will only increase as more complicated understandings of cross-sectional anatomy are required by advances and proliferation of imaging technology. Anat Sci Educ 3: 141-143, 2010. (C) 2010 American Association of Anatomists.

Epidemiological Aspects of Head Lice in Children Attending Day Care Centres, Urban and Rural Schools in Uberlândia, Central Brazil

From November 1996 to March 2000, a total of 884 children between 0 and 15 years, from 11 institutions including day care centres, public urban and public rural schools in Uberlândia, State of Minas Gerais, central Brazil, were examined for head louse infestation. Children's sex, race, age and some hairs characteristics were shown to be associated to parasite infestation. A prevalence rate of 35% was found and the highest rates were observed in black, female children, with long, dark, wavy hairs. Hairs density and thickness did not seem to influence significantly the distribution of this pediculosis in Uberlândia's schoolchildren. Differences observed between the prevalence rates of head lice in children from the urban institutions suggest there is a greater epidemiological heterogeneity in this group when compared to the rural schoolchildren.

"Royal" pediculosis in Renaissance Italy: lice in the mummy of the King of Naples Ferdinand II of Aragon (1467-1496)

Pediculosis seems to have afflicted humans since the most ancient times and lice have been found in several ancient human remains. Examination of the head hair and pubic hair of the artificial mummy of Ferdinand II of Aragon (1467-1496), King of Naples, revealed a double infestation with two different species of lice, Pediculus capitis, the head louse, and Pthirus pubis, the pubic louse. The hair samples were also positive for the presence of mercury, probably applied as an anti-pediculosis therapy. This is the first time that these parasites have been found in the hair of a king, demonstrating that even members of the wealthy classes in the Renaissance were subject to louse infestation.

Evolutionary relationships of "candidatus riesia spp.," endosymbiotic enterobacteriaceae living within hematophagous primate lice

The primary endosymbiotic bacteria from three species of parasitic primate lice were characterized molecularly. We have confirmed the characterization of the primary endosymbiont (P-endosymbiont) of the human head/body louse Pediculus humanus and provide new characterizations of the P-endosymbionts from Pediculus schaeffi from chimpanzees and Pthirus pubis, the pubic louse of humans. The endosymbionts show an average percent sequence divergence of 11 to 15% from the most closely related known bacterium "Candidatus Arsenophonus insecticola." We propose that two additional species be added to the genus "Candidatus Riesia." The new species proposed within "Candidatus Riesia" have sequence divergences of 3.4% and 10 to 12% based on uncorrected pairwise differences. Our Bayesian analysis shows that the branching pattern for the primary endosymbionts was the same as that for their louse hosts, suggesting a long coevolutionary history between primate lice and their primary endosymbionts. We used a calibration of 5.6 million years to date the divergence between endosymbionts from human and chimpanzee lice and estimated an evolutionary rate of nucleotide substitution of 0.67% per million years, which is 15 to 30 times faster than previous estimates calculated for Buchnera, the primary endosymbiont in aphids. Given the evidence for cospeciation with primate lice and the evidence for fast evolutionary rates, this lineage of endosymbiotic bacteria can be evaluated as a fast-evolving marker of both louse and primate evolutionary histories.

Bovine pericardium based non-cross linked collagen matrix for successful root coverage, a clinical study in human

Introduction The aim of this study was to clinically assess the capacity of a novel bovine pericardium based, non-cross linked collagen matrix in root coverage. Methods 62 gingival recessions of Miller class I or II were treated. The matrix was adapted underneath a coronal repositioned split thickness flap. Clinical values were assessed at baseline and after six months. Results The mean recession in each patient was 2.2 mm at baseline. 6 Months after surgery 86.7% of the exposed root surfaces were covered. On average 0,3 mm of recession remained. The clinical attachment level changed from 3.5 ± 1.3 mm to 1,8 ( ± 0,7) mm during the observational time period. No statistically significant difference was found in the difference of probing depth. An increase in the width of gingiva was significant. With a baseline value of 1.5 ± 0.9 mm an improvement of 2.4 ± 0.8 mm after six month could be observed. 40 out of 62 recessions were considered a thin biotype at baseline. After 6 months all 62 sites were assessed thick. Conclusions The results demonstrate the capacity of the bovine pericardium based non-cross linked collagen matrix for successful root coverage. This material was able to enhance gingival thickness and the width of keratinized gingiva. The percentage of root coverage achieved thereby is comparable to existing techniques. This method might contribute to an increase of patient's comfort and an enhanced aesthetical outcome.

Radiolabeled human monoclonal IgM for intracompartmental cancer therapy

Radioimmunotherapy (RIT) with i.v. administered radiolabeled IgG can selectively irradiate tumor cells in vivo. However, it only provides effective therapy for lymphomas. Intracompartmental RIT with radiolabeled human monoclonal IgM may allow curative treatment of solid tumors by increasing tumor deposition of radioactivity, reducing systemic toxicity and allowing repeated administration. This hypothesis was tested in nude mouse models with IgM radiolabeled with indium-111 $\rm(\sp{111}In)$ or yttrium-90 $\rm(\sp{90}Y).$ The use of two radioisotopes, $\rm\sp{111}In$ for imaging and $\rm\sp{90}Y$ for therapy, allow for more quantitative and cautious development of RIT.^ Radiolabled 2B12, an IgM reactive with human ovarian carcinomas was tested by i.v. and intraperitoneal (i.p.) administration in nude mice bearing i.p. nodules of a human ovarian carcinoma cell line (SKOV3 NMP2). Radiolabeled CR4E8, an IgM reactive with human squamous cell carcinomas was tested by i.v. and intralesional (i.l.) administration in nude mice bearing subcutaneous tumors of a human head and neck squamous cell carcinoma cell line (886). These two models were selected to test proof of concept. Radiolabeled irrelevant IgM (CH-1B9), and $\rm\sp{90}Y$-aggregate served as specificity controls. Biodistribution was performed by excising, weighing and then measuring the radioactivity of tumor and normal organs. Therapy was conducted with i.p. $\rm\sp{90}Y$-labeled 2B12 using both single and fractionated administration and with i.l. $\rm\sp{90}Y$-labeled CR4E8 using single administration. Mice were monitored for tumor response, survival and systemic toxicity.^ Intracompartmental administration of radiolabeled IgM produced immediate high and prolonged tumor deposition of radioactivity with low normal tissue uptake. In contrast, i.v. administration resulted in low tumor, but high liver and spleen uptake. Similar biodistributions were demonstrated for $\rm\sp{111}In$- and $\rm\sp{90}Y$-labeled IgM. Intraperitoneal therapy with $\rm\sp{90}Y$-labeled 2B12 increased survival by approximately 12 days for every 100 $\rm\mu Ci$ of activity without significant toxicity for single (0-300 $\rm\mu Ci)$ and fractionated (150-510 $\rm\mu Ci)$ administration. Intralesional therapy with $\rm\sp{90}Y$-labeled CR4E8 (150-400 $\rm\mu Ci)$ induced prolonged complete regressions. Significant local or systemic toxicity was not observed.^ Intracompartmental RIT with radiolabeled tumor-reactive human monoclonal IgM can selectively irradiate tumor cells. Intracompartmental radiolabled IgM can significantly extend the survival of treated mice with minimal toxicity. It deserves further development as a new cancer therapy. ^

Experimental tests in human-robot collision evaluation and characterization of a new safety index for robot operation

This paper describes an experimental procedure consisting of impact tests that simulate a collision of a human head with an industrial robot with the aim to validate a safety index named as New Index for Robots (NIR) and its outputs. The experiments in this paper are based on lab tests. It is an attempt to characterize the NIR index underlying the main parameters that are involved in crash interaction and to highlight limitations and weakness of suggested impact tests.

Electromagnetic fields inside a lossy, multilayered spherical head phantom excited by MRI coils: models and methods

The precise evaluation of electromagnetic field (EMF) distributions inside biological samples is becoming an increasingly important design requirement for high field MRI systems. In evaluating the induced fields caused by magnetic field gradients and RF transmitter coils, a multilayered dielectric spherical head model is proposed to provide a better understanding of electromagnetic interactions when compared to a traditional homogeneous head phantom. This paper presents Debye potential (DP) and Dyadic Green's function (DGF)-based solutions of the EMFs inside a head-sized, stratified sphere with similar radial conductivity and permittivity profiles as a human head. The DP approach is formulated for the symmetric case in which the source is a circular loop carrying a harmonic-formed current over a wide frequency range. The DGF method is developed for generic cases in which the source may be any kind of RF coil whose current distribution can be evaluated using the method of moments. The calculated EMFs can then be used to deduce MRI imaging parameters. The proposed methods, while not representing the full complexity of a head model, offer advantages in rapid prototyping as the computation times are much lower than a full finite difference time domain calculation using a complex head model. Test examples demonstrate the capability of the proposed models/methods. It is anticipated that this model will be of particular value for high field MRI applications, especially the rapid evaluation of RF resonator (surface and volume coils) and high performance gradient set designs.