Study of the skin anatomy with high-frequency (22 MHz) ultrasonography and histological correlation

AbstractThe present essay is aimed at getting the radiologist familiar with the basic histological skin structure, allowing for a better correlation with sonographic findings. A high-frequency (22 MHz) ultrasonography apparatus was utilized in the present study. The histological analysis was performed after the skin specimens fixation with formalin, inclusion in paraffin blocks and subsequent staining with hematoxylin-eosin. The authors present a literature review showing the relationship between sonographic and histological findings in normal cutaneous tissue, and discuss the technique for a better performance of the sonographic scan. High-frequency ultrasonography is an excellent tool for the diagnosis of different skin conditions. However, as this method is operator-dependent, it is crucial to understand the normal skin structure as well as the correlation between histological and sonographic findings.

The effects of fire severity on ectomycorrhizal colonization and morphometric features in Pinus pinaster Ait. seedlings

Aim of the study: Mycorrhizal fungi in Mediterranean forests play a key role in the complex process of recovery after wildfires. A broader understanding of an important pyrophytic species as Pinus pinaster and its fungal symbionts is thus necessary for forest restoration purposes. This study aims to assess the effects of ectomycorrhizal symbiosis on maritime pine seedlings and how fire severity affects fungal colonization ability. Area of study: Central Spain, in a Mediterranean region typically affected by wildfires dominated by Pinus pinaster, a species adapted to fire disturbance. Material and Methods: We studied P. pinaster root apexes from seedlings grown in soils collected one year after fire in undisturbed sites, sites moderately affected by fire and sites highly affected by fire. Natural ectomycorrhization was observed at the whole root system level as well as at two root vertical sections (0-10 cm and 10-20 cm). We also measured several morphometric traits ( tap root length, shoot length, dry biomass of shoots and root/shoot ratio), which were used to test the influence of fire severity and soil chemistry upon them. Main results: Ectomycorrhizal colonization in undisturbed soils for total and separated root vertical sections was higher than in soils that had been affected by fire to some degree. Inversely, seedling vegetative size increased according to fire severity. Research highlights: Fire severity affected soil properties and mycorrhizal colonization one year after occurrence, thus affecting plant development. These findings can contribute to a better knowledge of the factors mediating successful establishment of P. pinaster in Mediterranean forests after wildfires.

Immunotherapeutic targeting of LIGHT/LTβR/HVEM pathway fully recapitulates the reduced cytotoxic phenotype of LIGHT-deficient T cells.

Tumor necrosis factor (TNF)/TNF receptor (TNFR) superfamily members play essential roles in the development of the different phases of the immune response. Mouse LIGHT (TNFSF14) is a type II transmembrane protein with a C-terminus extracellular TNF homology domain (THD) that assembles in homotrimers and regulates the course of the immune responses by signaling through 2 receptors, the herpes virus entry mediator (HVEM, TNFSFR14) and the lymphotoxin β receptor (LTβR, TNFSFR3). LIGHT is a membrane-bound protein transiently expressed on activated T cells, natural killer (NK) cells and immature dendritic cells that can be proteolytically cleaved by a metalloprotease and released to the extracellular milieu. The immunotherapeutic potential of LIGHT blockade was evaluated in vivo. Administration of an antagonist of LIGHT interaction with its receptors attenuated the course of graft-versus-host reaction and recapitulated the reduced cytotoxic activity of LIGHT-deficient T cells adoptively transferred into non-irradiated semiallogeneic recipients. The lack of LIGHT expression on donor T cells or blockade of LIGHT interaction with its receptors slowed down the rate of T cell proliferation and decreased the frequency of precursor alloreactive T cells, retarding T cell differentiation toward effector T cells. The blockade of LIGHT/LTβR/HVEM pathway was associated with delayed downregulation of interleukin-7Rα and delayed upregulation of inducible costimulatory molecule expression on donor alloreactive CD8 T cells that are typical features of impaired T cell differentiation. These results expose the relevance of LIGHT/LTβR/HVEM interaction for the potential therapeutic control of the allogeneic immune responses mediated by alloreactive CD8 T cells that can contribute to prolong allograft survival.

Effects of modern variable frequency drive on the reliability of an old crane induction motor

The work aims to analyze the possibilities of utilizing old crane driving AC induction motors in modern pulse-width-modulated variable frequency drives. Bearing currents and voltage stresses are the two main problems associated with modern IGBT inverters, and they may cause premature failure of an old induction motor. The origins of these two problems are studied. An analysis of the mechanism of bearing failure is proposed. Certain types of bearing currents are considered in detail. The most effective and economical means are chosen for bearing currents mitigation. Transient phenomena of cables and mechanism of over voltages occurring at motor terminals are studied in the work. The weakest places of the stator winding insulation system are shown and recommendations are given considering the mitigation of voltage stresses. Only the most appropriate and cost effective preventative methods are chosen for old motor drives. Rewinding of old motors is also considered.

Effect of flushing frequency on emitter clogging in microirrigation with effluents

Flushing is an important maintenance task that removes accumulated particles in microirrigation laterals that can help to reduce clogging problems. The effect of three dripline flushing frequency treatments (no flushing, one flushing at the end of each irrigation period, and a monthly flushing during the irrigation period) was studied in surface and subsurface drip irrigation systems that operated using a wastewater treatment plant effluent for three irrigation periods of 540 h each. The irrigation systems had two different emitters, one pressure compensating and the other not, both molded and welded onto the interior dripline wall, placed in laterals 87 meters long. Dripline flow of the pressure compensating emitter increased 8% over time, while in the nonpressure compensating emitter, dripline flow increased 25% in the surface driplines and decreased 3% in the subsurface driplines by the emitter clogging. Emitter clogging was affected primarily by the interactions between emitter location, emitter type, and flushing frequency treatment. The number of completely clogged emitters was affected by the interaction between irrigation system and emitter type. There was an average of 3.7% less totally clogged emitters in flushed surface driplines with the pressurecompensating emitter as compared to flushed subsurface laterals with the nonpressure compensating emitter

Features extraction based on the Discrete Hartley Transform for closed contour

In this paper the authors propose a new closed contour descriptor that could be seen as a Feature Extractor of closed contours based on the Discrete Hartley Transform (DHT), its main characteristic is that uses only half of the coefficients required by Elliptical Fourier Descriptors (EFD) to obtain a contour approximation with similar error measure. The proposed closed contour descriptor provides an excellent capability of information compression useful for a great number of AI applications. Moreover it can provide scale, position and rotation invariance, and last but not least it has the advantage that both the parameterization and the reconstructed shape from the compressed set can be computed very efficiently by the fast Discrete Hartley Transform (DHT) algorithm. This Feature Extractor could be useful when the application claims for reversible features and when the user needs and easy measure of the quality for a given level of compression, scalable from low to very high quality.

Clinical features of oral lichen planus. A retrospective study of 65 cases

Objectives: To describe the clinical features of patients diagnosed with oral lichen planus (OLP) and to establish the prevalence of its malignant transformation in our setting. Study design: A retrospective study was made of 65 patients clinically and histologically diagnosed with OLP in the Service of Oral Surgery (Dental Clinic of the University of Barcelona, Spain) in the period 1990-2005. A descriptive and bivariate statistical analysis was made. Results: The mean patient age was 59 years (SD ± 14.9). Most of the patients (61%) were women, and the most frequent location of the lesions was the buccal mucosa (90.8%). White forms of OLP were noted in 66% of the cases, and 46.2% of the patients reported symptoms of some kind. The patients diagnosed with diabetes mellitus (20%) showed a larger proportion of red lesions (p=0.088). No statistically significant association was observed between chronic liver disease and the OLP lesion types or symptoms. Two cases of squamous cell carcinoma were identified in two patients previously or simultaneously diagnosed with OLP. A statistically significant correlation was observed between dysplastic changes / malignization of the lesions and smoking habit (p=0.019). An association to alcohol abuse was also noted, though in this case statistical significance was not reached (p=0.085). Conclusions: The clinical features of our study population were similar to those described in other studies. Diabetic patients with OLP were seen to be more susceptible to the development of atrophic-erosive lesions. Smokers and/or patients with alcohol abuse in turn showed a greater tendency to develop dysplastic changes / malignization in the histopathological study of the lesions

Ergonomics and musculoskeletal pain among postgraduate students and faculty members of the School of Dentistry of the University of Barcelona (Spain). A cross-sectional study

Objectives: To evaluate the intensity and location of musculoskeletal pain suffered by students and professors from different postgraduate programs of the School of Dentistry of the University of Barcelona (Spain), to identify the variables related to the occurrence of musculoskeletal symptoms and signs, and to establish possible preventive measures for such disorders. Materials and Methods: A cross-sectional study was made among students and faculty members from different postgraduate courses of the School of Dentistry at the University of Barcelona between May and June 2007. A total of 74 dentists (54 postgraduate students and 20 faculty members) completed an anonymous questionnaire containing 19 questions. The variables were divided into three main groups: sociodemographic information, ergonomic features and musculoskeletal pain arising from professional practice. Results: Most of the dentists (79.8%) had experienced some kind of musculoskeletal pain in the last 6 months. On comparing the different locations of pain (lumbar, cervical, dorsal, wrist, shoulder and others), the neck was found to be the most commonly affected location (58% of all subjects), and only 34% of the respondents took some preventive measures against musculoskeletal disorders. Women showed a higher frequency of intense pain involving the cervical, lumbar, dorsal and wrist areas (p<0.05). A higher incidence of wrist pain was recorded in professionals exclusively dedicated to oral surgery (p<0.05). No statistically significant correlation was found between the workload (hours) and pain in the different anatomical locations (p>0.05). Conclusions: An important incidence of pain symptoms secondary to musculoskeletal disorders was observed, particularly in the cervical region. Females and younger dentists showed a higher frequency of such symptoms. The implementation of preventive measures is necessary, in view of the high incidence of these disorders

Retrospective clinicopathological study of 418 odontogenic cysts

Objectives: To determine the relative incidence of odontogenic cysts and to identify the main clinicopathological features among patients treated in the Oral Surgery Department of the Dental Clinic of the University of Barcelona (Spain). Study design: A retrospective observational study was made of 418 odontogenic cysts diagnosed in 380 patients included in the database of 1235 histopathological diagnoses. The subjects were treated in the Master degree program of Oral Surgery and Implantology of the University of Barcelona in the period 1997-2006. The following variables were recorded: gender, age, clinical characteristics of the lesions (size and location), radiological features, duration, treatment, complications and relapses. A descriptive analysis was made of the study variables, using the SPSS version 15.0. Results: The incidence of odontogenic cysts was 33.8%. The mean patient age at appearance of the lesion was 42 years (range 7-83). The cysts were slightly more prevalent in males (58.4%). The lesion size ranged from 2-60 mm, with a mean size of 18.4 mm. The most frequent diagnosis was radicular cyst (50.2%). The most common location of the odontogenic cysts was in the mandible (61.5%), particularly the lower third molar region (36.8%). Conclusions: The most frequently diagnosed lesion was the radicular cyst. Odontogenic cysts were seen to be slightly more prevalent in males, and showed a high mandibular incidence. Knowledge of the biological and histological behavior of odontogenic cysts and their frequency are key aspects for ensuring early detection and adequate treatment.

Sharp mandibular bone irregularities after lower third molar extraction: Incidence, clinical features and risk factors

Objectives: The purpose of this study was to determine the incidence and clinical symptoms associated with sharp mandibular bone irregularities (SMBI) after lower third molar extraction and to identify possible risk factors for this complication. Study Design: A mixed study design was used. A retrospective cohort study of 1432 lower third molar extractions was done to determine the incidence of SMBI and a retrospective case-control study was done to determine potential demographic and etiologic factors by comparing those patients with postoperative SMBI with controls. Results: Twelve SMBI were found (0.84%). Age was the most important risk factor for this complication. The operated side and the presence of an associated radiolucent image were also significantly related to the development of mandibular bone irregularities. The depth of impaction of the tooth might also be an important factor since erupted or nearly erupted third molars were more frequent in the SMBI group. Conclusions: SMBI are a rare postoperative complication after lower third molar removal. Older patients having left side lower third molars removed are more likely to develop this problem. The treatment should be the removal of the irregularity when the patient is symptomatic

Market Opportunities for Paper Industry in Radio Frequency Identification

The paper industry has been experiencing remarkable structural changes since paper demand growth has ceased and some markets are declining. One reason behind the declined demand is the Internet, which has partially substituted the newspaper as a source of information. Paper products alone can no longer provide livelihood, and the paper industry has to find new business areas. In this research, we studied radio frequency identification (RFID), and the market opportunities it could provide for paper industry. The research combined a quantitative industry analysis and qualitative interviews. RFID is a growing industry in the beginning of its life cycle, in which value chains and technologies still evolve significantly. The industry is going to concentrate on the future, and in the long term RFID-identifiers will probably be printed on paper substrate or directly onto products. Paper industry has the chance to enter the RFID industry, but it has to obtain the required competences, for example through acquisitions. The business potential RFID offers to paper industry is inadequate, and while reviewing new strategic options, the paper industry must consider more options, for example the entire printed intelligence.

A hybrid feature selection approach for the early diagnosis of Alzheimer's disease

Objective. Recently, significant advances have been made in the early diagnosis of Alzheimer’s disease from EEG. However, choosing suitable measures is a challenging task. Among other measures, frequency Relative Power and loss of complexity have been used with promising results. In the present study we investigate the early diagnosis of AD using synchrony measures and frequency Relative Power on EEG signals, examining the changes found in different frequency ranges. Approach. We first explore the use of a single feature for computing the classification rate, looking for the best frequency range. Then, we present a multiple feature classification system that outperforms all previous results using a feature selection strategy. These two approaches are tested in two different databases, one containing MCI and healthy subjects (patients age: 71.9 ± 10.2, healthy subjects age: 71.7 ± 8.3), and the other containing Mild AD and healthy subjects (patients age: 77.6 ± 10.0; healthy subjects age: 69.4± 11.5). Main Results. Using a single feature to compute classification rates we achieve a performance of 78.33% for the MCI data set and of 97.56 % for Mild AD. Results are clearly improved using the multiple feature classification, where a classification rate of 95% is found for the MCI data set using 11 features, and 100% for the Mild AD data set using 4 features. Significance. The new features selection method described in this work may be a reliable tool that could help to design a realistic system that does not require prior knowledge of a patient's status. With that aim, we explore the standardization of features for MCI and Mild AD data sets with promising results.

The role of different factors related to social impact of heavy events: considerations about the intensity thresholds in densely populated areas

In the assessment of social impact caused by meteorological events, factors of different natures need to be considered. Not only does hazard itself determine the impact that a severe weather event has on society, but also other features related to vulnerability and exposure. The requests of data related to insurance claims received in meteorological services proved to be a good indicator of the social impact that a weather event causes, according to studies carried out by the Social Impact Research Group, created within the framework of the MEDEX project. Taking these requests as proxy data, diverse aspects connected to the impact of heavy rain events have been studied. The rainfall intensity, in conjunction with the population density, has established itself as one of the key factors in social impact studies. One of the conclusions we obtained is that various thresholds of rainfall should be applied for areas of varying populations. In this study, the role of rainfall intensity has been analysed for a highly populated urban area like Barcelona. A period without significant population changes has been selected for the study to minimise the effects linked to vulnerability and exposure modifications. First, correlations between rainfall recorded in different time intervals and requests were carried out. Afterwards, a method to include the intensity factor in the social impact index was suggested based on return periods given by intensity duration frequency (IDF) curves.

Generic features of eighteenth-century American runaway slave advertisements

Pro-gradu –tutkielmani aiheena ovat 1700-luvun ”karanneet orjat” – sanomalehtiilmoitusten genrelle ominaiset piirteet. Tutkimusaineisto koostuu 190 ilmoituksesta, jotka ovat alkuperäisesti ilmestyneet virginialaisissa, pennsylvanialaisissa ja newyorkilaisissa sanomalehdissä 1730-luvulta 1770-luvulle. Tutkimuksen kohteeksi on rajattu ilmoitukset, joissa yksityishenkilöt ilmoittavat orjan/orjien karanneet ja lupaavat kiinniottajalle palkkion. Tutkielman tarkoituksena on tarkastella, millaisia ovat tyypilliset kielelliset piirteet näissä teksteissä ja millainen on prototyyppinen genren edustaja. Genreteorian lisäksi teoriaosuudessa käsittelen jonkin verran 1700- luvun englannin kielen yleisiä piirteitä sekä orjuuden ja sanomalehtien syntyhistoriaa Amerikassa taustoittaakseni tutkimusta. Analyysissa hyödynnän mm. Swalesin ja Bhatian käyttämää käsitettä siirroista (moves). Tutkin ilmoituksien tyypillistä rakennetta jakamalla ne yhdeksään siirtoon, joilla kaikilla on oma tehtävänsä ilmoituksessa. Jotkut siirrot, kuten karkulaisen kuvailu ja palkkion lupaaminen, esiintyvät kaikissa ilmoituksissa, kun taas toiset siirrot ovat läsnä harvemmin. Muita tälle genrelle tyypillisiä ominaisuuksia ovat esim. ilmoituksissa toistuvat kiinteät fraasit ja tietyt sanastolliset erikoisuudet. Lisäksi tutkin ilmoituksissa käytettäviä tapoja viitata asiaan liittyviin henkilöihin, sekä erilaisia toimia, joita ilmoitusten jättäjät ilmoituksien avulla suorittavat. Genressä on havaittavissa pieniä reilun neljänkymmenen vuoden kuluessa tapahtuneita muutoksia, mutta myös eroavaisuuksia eri siirtokuntien ilmoitusten välillä. Yleisesti voidaan todeta, että vaikka ”karanneet orjat” –ilmoitukset voivat vaihdella rakenteeltaan ja sanavalinnoiltaan, suuri osa ilmoituksista seuraa kuitenkin melko prototyyppistä muottia.

Radio Frequency Measurement Method for Detecting Bearing Currents in Induction Motors

Induction motors are widely used in industry, and they are generally considered very reliable. They often have a critical role in industrial processes, and their failure can lead to significant losses as a result of shutdown times. Typical failures of induction motors can be classified into stator, rotor, and bearing failures. One of the reasons for a bearing damage and eventually a bearing failure is bearing currents. Bearing currents in induction motors can be divided into two main categories; classical bearing currents and inverter-induced bearing currents. A bearing damage caused by bearing currents results, for instance, from electrical discharges that take place through the lubricant film between the raceways of the inner and the outer ring and the rolling elements of a bearing. This phenomenon can be considered similar to the one of electrical discharge machining, where material is removed by a series of rapidly recurring electrical arcing discharges between an electrode and a workpiece. This thesis concentrates on bearing currents with a special reference to bearing current detection in induction motors. A bearing current detection method based on radio frequency impulse reception and detection is studied. The thesis describes how a motor can work as a “spark gap” transmitter and discusses a discharge in a bearing as a source of radio frequency impulse. It is shown that a discharge, occurring due to bearing currents, can be detected at a distance of several meters from the motor. The issues of interference, detection, and location techniques are discussed. The applicability of the method is shown with a series of measurements with a specially constructed test motor and an unmodified frequency-converter-driven motor. The radio frequency method studied provides a nonintrusive method to detect harmful bearing currents in the drive system. If bearing current mitigation techniques are applied, their effectiveness can be immediately verified with the proposed method. The method also gives a tool to estimate the harmfulness of the bearing currents by making it possible to detect and locate individual discharges inside the bearings of electric motors.