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Fine-grain tactile sensing has recently gained much attention in robotics applications where the manipulation of potentially fragile objects must be provided. This has led to the emergence of electronic skin (e-skin) sensors, usually implemented with conventional frame-based acquisition chains. In addition, prosthetics applications require e-skins with human-level, sub-millimeter spatial resolution. This paper proposes to study two types of spike-based e-skin readout circuits, based on conventional and neuromorphic level crossing architectures. Compared to prior frame-based, coarse spatial resolution readout schemes, a sub-millimeter spiking e-skin scheme is modeled and compared to its frame-based counterpart in terms of power consumption and texture classification accuracy, using a Spiking Neural Network. Our analysis shows that the sparsity-inducing spike-based solutions achieve one order of magnitude lower power consumption while reaching a higher classification accuracy (87.92%) compared to the frame-based readout (74.58%). ispartof: pages:359-363 ispartof: 2022 IEEE Biomedical Circuits and Systems Conference (BioCAS) pages:359-363 ispartof: IEEE Biomedical Circuits and Systems Conference (BioCAS) 2022 location:Taipei, Taiwan date:13 Oct - 15 Oct 2022 status: Published online

Radar processing via spiking neural networks (SNNs) has recently emerged as a solution in the field of ultra-low-power wireless human-computer interaction. Compared to traditional energy- and area-hungry deep learning methods, SNNs are significantly more energy efficient and can be deployed in the growing number of compact SNN accelerator chips, making them a better solution for ubiquitous IoT applications. We propose a novel SNN strategy for radar gesture recognition, achieving more than 91% of accuracy on two different radar datasets. Our work significantly differs from previous approaches as 1) we use a novel radar-SNN training strategy, 2) we use quantized weights, enabling power-efficient implementation in real-world SNN hardware, and 3) we report the SNN energy consumption per classification, clearly demonstrating the real-world feasibility and power savings induced by SNN-based radar processing. We release evaluation code to help future research.

Motivation Canonical forms of the antibody complementarity-determining regions (CDRs) were first described in 1987 and have been redefined on multiple occasions since. The canonical forms are often used to approximate the antibody binding site shape as they can be predicted from sequence. A rapid predictor would facilitate the annotation of CDR structures in the large amounts of repertoire data now becoming available from next generation sequencing experiments. Results SCALOP annotates CDR canonical forms for antibody sequences, supported by an auto-updating database to capture the latest cluster information. Its accuracy is comparable to that of a standard structural predictor but it is 800 times faster. The auto-updating nature of SCALOP ensures that it always attains the best possible coverage. Availability and implementation SCALOP is available as a web application and for download under a GPLv3 license at opig.stats.ox.ac.uk/webapps/scalop. Supplementary information Supplementary data are available at Bioinformatics online.

Summary In this paper are presented the results obtained by the light scattering method of a systematic study of different parameters characterizing spermatozoa motility in a series of human sperms, one hour and five hours after ejaculation. These results are relative to the concentration of spermatozoa, the percentage and the number of motile spermatozoa, the characteristic velocity and the velocity distributions. All these parameters are discussed one by one, the advantages (objectivity, small quantity of not diluted sperm, short time needed for measurements) and the limits of the light scattering method being pointed out. A comparison is made with results obtained by conventional methods. The fineness of this study shows that this method can be used with success in fundamental research as well as in a routine functional sperm study, allowing an objective and precise analysis of motility in a given population as a complex factor. Zusammenfassung Eine systematische Studie der verschiedenen fur die Motilitat der Spermatozoen kennzeichnenden und durch die Lichtstreuungsmethode gerechneten Parameter wurde in dieser Arbeit zusammengefast. Die Untersuchungen umfassen eine Serie eine Stunde und funf Stunden nach der Ejakulation erhaltener menschlicher Spermatozoen. Die Spermatozoenkonzentration, der Prozentsatz an beweglichen Spermatozoen, die Anzahl der letzteren, die charakteristische Geschwindigkeit und die Geschwindigkeitsverteilung wurden jeweils angegeben. Jeder Parameter wurde einzeln im Zusammenhang mit den Vorteilen der Methode (d.h. ihrer Objektivitat, der Anwendung von relativ kleinen Mengen unverdunnten Spermas, den schnell gerechneten Werten) sowie deren Grenzen diskutiert. Anschliesend wurden die Befunde mit den durch konventionelle Methoden erhaltenen Ergebnissen verglichen. Wegen ihrer Prazision kann diese Methode erfolgreich im Gebiet der Grundlagen-Forschung sowie im Rahmen einer funktionellen Routinespermatozoenstudie angewendet werden, indem sie eine objektive und genaue Analyse der Motilitat der Spermatozoen als komplexen Faktors ermoglicht. Resumen Se presentan los resultados obtenidos por el Metodo de dispersion optica de un estudio sistematico de diferentes parametros que caracterizan la motilidad espermatica en una serie de espermas humanos, 1 y 5 horas despues de la eyaculacion. Estos resultados son relativos a la concentracion de espermatozoides moviles, caracteristica y distribucion de la velocidad. Se discuten todos estos parametros uno por uno, la ventaja (objetividad, pequena cantidad de esperma no diluido, rapidez de la medicion) y se apuntan los limites del metodo de dispersion optica. Se comparan los resultados con los obtenidos por metodos convencionales. La perfeccion de este estudio muestra que este metodo se puede utilizar con exito en investigacion fundamental aski como en el estudio funcional rutinario del espermatozoide, permitiendo un analisis preciso y objetivo de la movilidad en una poblacion dada.

Whether well founded or not, perceptions of one’s own HIV risk have been shown by health behavior models to be an important factor in determining individuals’ sexual behavior. Although empirical studies on the determinants of HIV risk perception exist, only a few have focused on adolescents who are not yet sexually active. Using data from nationally- representative surveys of adolescents, we assess the factors associated with HIV risk perception among sexually inactive adolescents in four sub-Saharan African countries at different stages of the HIV/AIDS epidemic (Burkina Faso, Ghana, Malawi and Uganda). The results show that there is no single influence on adolescents’ HIV risk perception, but rather a range of individual, environmental and community factors such as schooling, knowledge about HIV, regional HIV prevalence and adolescents’ social networks. These results can help better calibrate programs and policies addressing sexual and reproductive health issues among adolescents, a group that is disproportionately affected by new HIV infections. Afr J Reprod Health 2013 (Special Edition); 17[4]: 32-50).Keywords: HIV/AIDS, risk perception, ordered logistic analysis, Burkina Faso, Ghana, Malawi, Uganda

Background and Objective The lack of myofibroblasts, cells responsible for wound contraction, has been suggested to be the underlying factor to the clinically observed minimal contraction in CO2 laser wounds. However, the histologic background to this phenomenon in laser excisions has not been thoroughly clarified. Therefore, we analyzed the expression of myofibroblasts in healing laser excisions and control excisions made by scalpel. Study Design/Materials and Methods CO2 laser (continuous wave, 5 W) or scalpel excision wounds were created in the dorsal tongue mucosa of 144 rats. Sixteen additional rats were kept as untreated controls. Specimens from the tongues were cut at 16 different healing time points and fixed in 10% formalin. Immunohistochemical stainings with monoclonal antibodies to vimentin and to α-smooth muscle actin were done to determine microscopically the contractile type of myofibroblasts. Results The maximum amount of myofibroblasts was almost three times higher in scalpel than in laser excisions. The peak value was reached at 4 days in laser and at 3 days in scalpel wounds. The increase reverted to normal levels at 14 days in laser and at 6 days in scalpel wounds, respectively. Conclusion Myofibroblasts appeared and disappeared slower in laser wounds. There were clearly fewer myofibroblasts in CO2 laser than in corresponding scalpel excisions known to heal by contraction. The lack of contractile myofibroblasts, therefore, is suggested as the reason for the minimal degree of contraction in CO2 laser excision wounds. Lasers Surg. Med. 28:74–79, 2001. © 2001 Wiley-Liss, Inc.

'Race' for many years has been a major construct of science and society. While its importance as such has not historically been particularly pronounced on a global scale, the emergence of its most forceful architects, the Anglophone countries, to pre-eminence since World War II has significantly extended its geographical range and added to its significance as an idea within commercialized culture as well as within social organization.

In liquid alcohols there are a definite number N hb of H-bonds for a given number N a of molecules. The ratio r f = 1 − ( N hb N a ) can be deduced from the IR spectrometric data of Luck. However the NMR results show that these H-bonds perpetually jump from one partner to another. The chance j non-bonded over time that a given molecule, taking advantage of these jumps, becomes free from H-bonding is equal to r f . This agrees with the vapor pressure data. However, it can be shown that the fraction α OH of the molecules in the ensemble which are completely free from H-bonding, acting neither as donor nor as acceptor is of the order of r f 2 , and thus much smaller than the time fraction j non-bonded . This non-ergodic behaviour can be explained by the fact that only molecules which are completely inserted in a chain, acting at the same time in H-bonding as proton donor and as proton acceptor (fraction α -OH- ) are in full possession of the energy of an H-bond, Δ H h-bond /L. One cannot attribute this energy to all the molecules which form only an H-bond on one side (fractions α -OH and α OH- ) because this would not fit the energy balance. These states have to be considered as transient ones during the life-time of which the energy Δ H h-bond /L passes from the medium to the molecule or vice-versa. As a consequence, in the ensemble, the energy of these states cannot be defined, but this is quite possible in a time schedule, such molecules being then considered during half of their life-time as possessing the energy Δ H h-bond /L, and during the remaining half as free. This means that the ensemble fraction α -OH contributes half to the time fraction j non-bonded , half to the time fraction j bonded . Non-ergodicity will be observed for all the liquid systems where in the ensemble states are found to which the energy of an ephemeral cohesion bond cannot unambiguously be attributed, because they have to be considered as transient forms during the non-negligible life-time of which this energy is transferred from the medium to the molecule or vice-versa. This will be the case for the molecules at the head or at the tail of all open transient chains. In such non-ergodic systems the thermodynamic probability has to be calculated, not on the basis of ensemble fractions, but on the basis of the time fractions during which the energy of the ephemeral bonding can be attributed or not to a given molecule. The use of time fractions for calculating the thermodynamic probability was already proposed by Einstein in 1911. The consequences of the non-ergodicity for the statistical thermodynamics of H-bonding are discussed. The correctness of the non-ergodic thermodynamics of hydrogen bonded liquids, based on time fractions, is demonstrated by the fact that the derived equations allow to predict correctly, without any adjustable parameter, the solubilities of the alkanes in alcohols and in water. Here, the classical theories completely fail.

The various characteristics used to describe Forcipatorina and to fix its limits with Clivinina are analyzed and checked against the different genera concerned. New definitions for the subtribes and a key to the genera included in Forcipatorina are given. It is shown that the genus Stratiotes Putzey s is heterogenous and must be divided into several genera, two of which are described as new: Kultianella and Whiteheadiana.

Amperometric bioelectrodes based on carbon paste mixed with glucose oxidase (GOX) and dimethylferrocene (DMFc), are characterized by using cyclic voltammetry, potential step chronoamperometry and amperometry at a rotating disk electrode. The catalytic process appears to be highly dependent on the amount of DMFc. Kinetic control, internal diffusion control and external diffusion control can be obtained only by varying the amount of incorporated DMFc. It was shown that the Eadie-Hofstee plot is a particularly useful tool in diagnosis of diffusional limitations. The high efficiency of electrochemical regeneration of high amounts of DMFc∗ surrounding GOX solves the problem of co-substrate transport. The catalytic oxidation current of ascorbic acid was highly diminished by casting a lipid/Nafion membrane and totally eliminated by treatment of the sample with hydrogen peroxide prior to measurement.

A 250-mm imaging spectrograph was combined with a CCD detector, fiber-optic sampler, and diode laser (783 nm) to yield an efficient Raman spectrometer. A variety of sampling modes for liquids and solids were demonstrated, none of which required careful optical alignment. Of practical interest are spectra obtained from liquids inside glass containers, rapid (30 seconds each) spectral acquisition from successive solid and liquid samples, and spectra of normally fluorescent materials such as rhodamine 6G and common plastics.

Genus Leistus Froehlig (Coleoptera Carabidae Nebriini). XIII. L. rufomarginatus Duftschmid and L. ovipennis Chaudoir groups The groups of Leistus rufomarginatus Duft. and L. ovipennis Chaudoir, with three species, are closely related. L. rufomarginatus is a species with a very wide distribution range, still in expansion, while L. hermonis La Brûlerie, is restricted to Near-East and L. ovipennis to a few localities on the southern side of the Alps., L'ensemble des groupes de Leistus rufomarginatus Duft. et de L. ovipennis Chaudoir est assez homogène. Il comprend trois espèces. L. rufomarginatus est une espèce à très large distribution, actuellement en voie d'extension, alors que L. hermonis La Brûlerie est limité au Proche-Orient et L. ovipennis à une série de localités sur le versant sud des Alpes., Perrault Georges G. Le genre Leistus Froehlig (Coleoptera Carabidae Nebriini). XIII -Les groupes de L. rufomarginatus Duftschmid et L. ovipennis Chaudoir. In: Bulletin mensuel de la Société linnéenne de Lyon, 60ᵉ année, n°3, mars 1991. pp. 86-93.

Genus Leistus Froehlig (Coleoptera Carabidae Nebriini) XV. Subgenus Leistus s. str. (3). The Euromaghrebian species Thirteen European species are placed in subgenus Leistus s. str., six of which belong to the L. angusticollis group occurring in the Iberian peninsula, three to the L. ferrugineus group and four to the L. fulvibarbis group. Only two subspecies are recognized : L. piceus alpicola Fuss and L. fulvibarbis danieli Reitter. The holotype of L. oberthueri Reitter has been determined and its synonymy with L. fulvibarbis Dejean established., Le sous-genre Leistus s. str. est représenté en Europe par 13 espèces, dont 6 appartiennent au groupe de L. angusticollis Dejean occupant le nord-ouest de la péninsule ibérique, 3 au groupe de L. ferrugineus L. et 4 au groupe de L. fulvibarbis Dejean. Deux sous-espèces seulement sont reconnues : L. piceus alpicola Fuss et L. fulvibarbis danieli Reitter. On désigne l'holotype de L. oberthueri Reitter qui est considéré comme synonyme de L. fulvibarbis., Perrault Georges G. Le genre Leistus Froehlig (Coleoptera Carabidae Nebriini). XV. Sous-genre Leistus s. str. (3). Les espèces euromaghrébines. In: Bulletin mensuel de la Société linnéenne de Lyon, 60ᵉ année, n°6, juin 1991. pp. 186-200.

Genus Leistus Froehlig (Coleoptera Carabidae Nebriini). XII. Subgenus Neoleistus Erwin : the group of L. niger Gebler. Three Asian species belong to subgenus Neoleistus Erwin, one of which : L. shenseensis being described as new. A lectotype is designated for L. angulicollis Fairmaire., En Asie, le sous-genre Neoleistus Erwin comprend trois espèces dont l'une : L. shenseensis est décrite comme nouvelle ; et on désigne un lectotype pour L. angulicollis Fairmaire., Perrault Georges G. Le genre Leistus Froehlig (Coleoptera Carabidae Nebriini). XII - Le sous-genre Neoleistus Erwin : Le groupe de L. niger Gebler. In: Bulletin mensuel de la Société linnéenne de Lyon, 60ᵉ année, n°1, janvier 1991. pp. 14-19.

Summary form only given, as follows. Although analogue and mixed-signal design is greatly complicated by numerous design choices, the management of these design choices presents significant opportunities for optimising designs for desired tradeoffs in performance and high production yield. This tutorial describes analog design and EDA methods beginning with MOS transistors and concluding with PLLs as complete mixed-signal systems. Tutorial topics include: (1) tradeoffs and optimisation in analogue CMOS design through transistor drain current, inversion coefficient, and channel length selections; (2) transistor sizing rules, rules for transistor groups, and robust Pareto optimisation of circuits; (3) analogue synthesis, hierarchical design, and yield optimisation; and (4) behavioral modelling of oscillators and PLLs using nonlinear phase macro models that capture jitter and phase noise, injection locking, PLL lock and capture phenomena, and cycle slipping. Tutorial topics are interrelated with each other and illustrated using actual designs. Finally, future directions for analogue design and EDA are suggested, including applications to biological systems such as mammalian circadian rhythms. This tutorial is targeted to analogue and mixed-signal designers, EDA developers and users, design managers, and advanced university students.

Desde o início da década de 1990, a Amazônia legal brasileira vem sendo palco da expansão do plantio de soja e da atuação de empresas esmagadoras de grãos. Nos últimos anos a logística instalada pelo complexo agroindustrial sojicultor, a partir de produtores, fornecedores de insumos, processadores de matérias primas, assume um caráter estratégico e promove o avanço de novas fronteiras agrícolas no interior da região. A abundância de terras agriculturáveis, juntamente com a facilidade de escoamento via transporte fluvial através dos rios que cortam a bacia amazônica para o oceano Atlântico e daí para mercados consumidores na América do Norte, Europa e Ásia, são elementos que chamam a atenção das grandes tradings internacionais, e de empresas nacionais, que visam o mercado interno, mas principalmente o agronegócio exportador. Esses grupos empresariais criam vínculos econômicos entre o espaço regional e o comércio internacional. Neste sentindo este artigo busca analisar o contexto mais geral desta discussão, discutindo o lugar estratégico da cadeia de soja no processo de inserção global do sistema agroalimentar brasileiro, mas centrado foco em dois estudos de caso na região amazônica: Santarém no Pará e Humaitá no Amazonas.

Although there are a number of visualization systems to choose from when analyzing data, only a few of these allow for the integration of other visualization and analysis techniques. There are even fewer visualization toolkits, frameworks and developmental systems from which one can develop custom visualization applications. Even within the research community, scientists either use what they can from the available tools or start from scratch to define a program in which they are able to develop new or modified visualization techniques. This research presents a new general-purpose platform in which the design and experimentation of new visualization and analysis techniques is the focus, and where the sharing of and integration with other techniques becomes second nature. Here we introduce the Universal Visualization Platform (UVP) as a data visualization and analysis system supporting future research and modern discovery environments. Furthermore, we present a novel perspective on the Model-View-Controller programming paradigm that defines visualizations as views of models. Finally, we present a new layer model specifying the construction and manipulation of visualizations. Here, layers containing graphic elements that encode information are rendered together using composition operators to generate visual displays.

Calcul des diagrammes d'equilibre electrochimique pour les systemes: gallium-eau, arsenic-eau, arseniure de gallium-gallium-arsenic-eau. Determination des proprietes thermodynamiques (enthalpie, energie libre de Gibbs)

Subgenus Evanoleistus Jedlicka species are found from Japan to Pakistan. They can be distributed into two groups. The L. nepalensis Jedl. group is restricted to the Himalayas, while the five species of the L. crassus Bates group are found from Japan to Népal, one of them : L. birmanicus being described as new., Le sous-genre Evanoleistus Jedlicka, est répandu du Japon au Pakistan. Il se divise en deux groupes distincts dont l'un, celui de L. nepalensis Jedl., ne se trouve que dans les chaînes himalayennes, alors que le groupe de Leistus crassus Bates, réparti du Japon au Népal renferme 5 espèces dont l'une : L. birmanicus est décrite comme nouvelle., Perrault Georges G. Le genre Leistus Froehlig (Coleoptera -Carabidae -Nebriini). VI. Le sous-genre Evanoleistus Jedlicka. In: Bulletin mensuel de la Société linnéenne de Lyon, 54ᵉ année, n°1, janvier 1985. pp. 13-24.

The Leistus angusticollis group from Spain has been studied. The geographic range and the diagnostic caracters are given for each of the 6 species here recognized : L. angusticollis Dejean, L. acutangulus n. sp., L. oopterus Chaudoir, L. barnevillei Chaudoir, L. angulatus La Brûlerie, L. constrictus Schauffuss. L. aculeatus is a synonym of L. angusticollis Dejean., Résumé. — On étudie les Leistus orophiles appartenant au groupe de L. angusticollis Dejean, du nord de la Péninsule ibérique. Pour chaque espèce on précise les caractéristiques et la distribution. On sépare ainsi 6 espèces : L. angusticollis Dejean, L. acutangulus n. sp., L. oopterus Chaudoir, L. barnevillei Chaudoir, L. angulatus La Brûlerie, L. constrictus Schauffuss. On établit la synonymie de L. aculeatus Jeanne et de L. angusticollis Dejean., Perrault Georges G. Le genre Leistus (Froehlig) (Coleoptera - Carabidae). I. Le groupe de Leistus angusticollis (Dejean). In: Bulletin mensuel de la Société linnéenne de Lyon, 48ᵉ année, n°1, janvier 1979. pp. 53-64.

In parallel with further description of several Asian species of the L fulvibarbis Dejean group, typical material for L. caucasicus Chaudoir, L. femoralis Chaudoir, L. fulvus Chaudoir, L. denticollis Reitter, L. angustus Reitter and L. frater Reitter is designated., Avec la description des différentes espèces asiatiques du groupe de L. fulvibarbis Dejean, on procède à la désignation du matériel type pour L. caucasiens Chaudoir, L. femoralis Chaudoir, L. fulvus Chaudoir, L. denticollis Reitter, L. angustus Reitter et L. frater Reitter., Perrault Georges G. Le genre Leistus Froehlig (Coleoptera, Carabidae, Nebriini). X. Sous-genre Leistus s. str. (2). Les espèces asiatiques (suite). In: Bulletin mensuel de la Société linnéenne de Lyon, 57ᵉ année, n°2, février 1988. pp. 44-56.

Only two species described by Wollaston belong to subgenus Nebrileistus Bànninger : L. ellipticus from Madeira and L. nubivagus from Tenerife (Canarias)., Le sous-genre Nebrileistus Bànninger comprend seulement deux espèces, décrites par Wollaston, habitant les îles atlantiques : L. ellipticus de Madère et L. nubi-vagus de Tenerife (Canaries)., Perrault Georges G. Le genre Leistus (Froehlig) (Col. Carabidae). III. Le sous-genre Nebrileistus (Banninger). In: Bulletin mensuel de la Société linnéenne de Lyon, 50ᵉ année, n°7, septembre 1981. pp. 222-226.

Atmospheric aerosol particles have been sampled near a Los Angeles freeway and analyzed by proton-induced X-ray emission, PIXE, as a sulfur baseline study in September 1974 before 1975-model auto mobiles, equipped with catalytic emission control devices, appeared in large numbers. The sampling plan was optimized a c cording to the requirements of X-ray analysis techniques, fluctuations in air flow across the freeway, and the time and particlesise resolution of the aerosol sampling equipment. During five selected two-hour intervals with cross wind conditions, particles were collected as a function of size by six cascade impactorsope rating simultaneously on three towers at 2 and 7 meters above road level 35 meters upwind and 35 meters downwind of the traffic lanes. Particles as a function of time were sampled continuously, for the 100-hour duration of the experiment, from the three 7-meter heights using time series streaker filter samplers with two-hour time resolution. Precise analyses of S, Cl, K, Ca, Fe, Br, and. Pb established relationships which permit estimates to be made of future increases in particulate sulfur as a consequence of increased sulfate emissions from catalytic automobiles.

An automatic time sequence filter sampler has been developed for atmospheric aerosol particle sampling of ambient air and subsequent analysis for elemental composition using the proton, beam of a Van de Graaff accelerator. Some features of the operation of the sampler are given, the retention of particles by the filter material are discussed, examples of the type of data obtained are presented, and some approaches to the numerical analysis of data for environmental interpretation are considered. Lines for further development and improvement in this type of sampler are indicated.

Twenty-two N-substituted derivatives of the carcinostatic 6-aminochrysene have been tested as potential carcinostatic agents (using 6-aminochrysene as a standard) on spontaneous mammary tumor in [C3H/020] F1 mice, and on the slow-growing transplanted rhabdomyosarcoma in inbred WAG/Rij rats. Many of these compounds displayed important activity against both types of tumor, and some of them merit further investigations. In contrast compounds active on these experimental tumors, were completely inactive on Ehrlich carcinoma and on Sarcoma 180.

Summary We have studied the Mg electrode in aqueous solution using various potentiostatic techniques. The steady state study indicates the presence of an oscillation phenomenon in the cathodic range of potential. Voltage sweep techniques show the great stability of the cathodic film and slow rate of transformation of the anodic layer. Using the pulse technique we have measured the impedance of the electrode in the anodic potential range and studied the transformation between the anodic layer and the cathodic film. Besides the effect of the electrolyte the results show the need to consider at least two antagonistic reactions and an intermediate species in the dissolution of the anode. A mechanism involving magnesium hydride is proposed for this dissolution.

Perrault Georges G. Une espèce nouvelle de Leleupidiini d'Asie : Colasia gerardi n. sp. de Bornéo (Coleoptera, Carabidae). In: Bulletin mensuel de la Société linnéenne de Lyon, 51ᵉ année, n°3, mars 1982. pp. 76-78.

Proton induced X-ray emission analysis is useful in measuring changes in particle size distribution of trace elements on exposure of aerosol to the human lung environment and deposition in the air-ways. PIXE analysis is also useful in detecting variations in particle size distributions of elements as they occur in the atmosphere. For the case of lead aerosol along a highway, it is shown that the extent and site of respiratory deposition of particles depend on their size, and the size distribution may vary under urban atmospheric conditions sufficiently to affect respiratory deposition efficiency.

Long term topical skin application of 6-aminochrysene (6-AMC) to mice induced development of benign skin tumours after 3 months and of skin malignancies after 7 months. Primitive cutaneous tumours arose at the site of application and other lesions arose elsewhere on the skin and in the viscera. Gross and histopathological examination revealed that 92% of mice in the 6-AMC treated groups carried tumours, compared to 6 and 5% respectively in vehicle-treated and untreated controls. In the 6-AMC treated mice, lung tumours were observed in 71% of the animals and liver lesions in 38%. Female mice responded earlier than males. Induction of skin tumours was more rapid when 6-AMC was applied ventrally instead of dorsally. Bioavailability studies with 3H-6-AMC indicated that urinary excretion is about twice as high after skin application than after oral administration.

Respiratory response to inhalation of fine particles has been investigated for the aerosol generated by welding. Particles were sampled using a pair of 5-stage cascade impactors operating at 1 l./min flow rate. The subject exhaled into one impactor through an air ballast arrangement, and the other impactor simultaneously sampled the surrounding air. Particle size fractions were analyzed for principal elemental constituents from sulphur to lead using proton induced X-ray emission, PIXE. The results indicated a complex respiratory response, including both increase in particle size due to exposure to high humidity in the respiratory tract and deposition of particles during inhalation. The response was found to be different for the element group Mn, Cr, Fe, Ni compared to the group K, Ca, Ti by observing the associations among the elements as a function of particle size in the inhaled and exhaled aerosol. However, for respiratory deposition efficiency alone in all runs averaged together, no systematic differences between the different elements are demonstrated at the 99 % confidence level.

To find whether on a toroidal group ¢n/Γ any meromorphic function can be written as the quotient of two θ-functions associated with the lattice Γ one has to study the existence of ℤn-periodic entire solutions of a system of difference equations. The formal series solutions are shown to converge "generically". This gives a partial answer to a question of A. Andreotti as to find "good conditions" for the convergence of the series that occur in the construction of the θ-functions associated with Γ.