Geo-environmental zoning using physiographic compartmentalization: a proposal for supporting sustainable decision-making.

The geo-environmental zoning represents an important strategy in the territorial management. However, it requires a logical and structured procedure. Therefore, an approach using physiographic compartmentalization is proposed and applied as case study in a region covered by the topographic maps of São José dos Campos and Jacareí, Brazil. This region has great geological and geomorphological peculiarities, beyond being a place with large human interventions because of its quickly economic growth. The methodology is based on photointerpretation techniques and remote sensing in GIS environment. As a result, seven geo-environmental zones were obtained from a weighted integration by multicriteria analysis of physiographic units with land-use classes. In conclusion, taking into account potentialities and limitations, the proposed approach can be considered able to support sustainable decision-making, being applicable in other regions.

Stimulus Dependence of Gamma Oscillations in Human Visual Cortex.

A striking feature of some field potential recordings in visual cortex is a rhythmic oscillation within the gamma band (30-80 Hz). These oscillations have been proposed to underlie computations in perception, attention, and information transmission. Recent studies of cortical field potentials, including human electrocorticography (ECoG), have emphasized another signal within the gamma band, a nonoscillatory, broadband signal, spanning 80-200 Hz. It remains unclear under what conditions gamma oscillations are elicited in visual cortex, whether they are necessary and ubiquitous in visual encoding, and what relationship they have to nonoscillatory, broadband field potentials. We demonstrate that ECoG responses in human visual cortex (V1/V2/V3) can include robust narrowband gamma oscillations, and that these oscillations are reliably elicited by some spatial contrast patterns (luminance gratings) but not by others (noise patterns and many natural images). The gamma oscillations can be conspicuous and robust, but because they are absent for many stimuli, which observers can see and recognize, the oscillations are not necessary for seeing. In contrast, all visual stimuli induced broadband spectral changes in ECoG responses. Asynchronous neural signals in visual cortex, reflected in the broadband ECoG response, can support transmission of information for perception and recognition in the absence of pronounced gamma oscillations.

The utility of Amies charcoal bacteriology swabs for storage of canine urine prior to culture.

OBJECTIVE: To determine the usefulness of bacteriology swabs as a storage method of canine urine samples and the effect on quantitative bacterial culture. MATERIALS AND METHODS: Two hundred fourteen canine urine samples were collected by cystocentesis. The reference aliquot was placed in a sterile tube and processed for quantitative bacterial culture within 6 hours. A bacteriology swab was then immersed in the urine for 5 seconds and returned to the charcoal Amies media container. The urine samples in the sterile tube and bacteriology swab were stored at room temperature for 48 hours and processed for quantitative bacterial culture. RESULTS: Thirty-seven of the samples were positive on reference culture with a total of 42 bacterial isolates. Samples stored in sterile tube and bacteriology swab had identical sensitivity and specificity for detection of bacteriuria (94.7% and 100%, respectively) with very good agreement (κ = 0.92; 95% CI 0.81 to 1.00). Agreement between the bacterial species of the reference sample and the bacteriology swab was higher (κ = 0.85; 95% CI 0.71 to 0.99) than compared to the sterile tube (κ = 0.78; 95% CI 0.62 to 0.94), but the overlapping confidence intervals mean improved agreement cannot be inferred. CLINICAL SIGNIFICANCE: Bacteriology swabs stored in Amies charcoal transport media should be considered an alternative method to preserve canine urine sample when immediate processing for quantitative bacterial culture is not possible. The sensitivity of culturing plain urine, stored for 48 hours in a sterile tube, for detection of bacteriuria, was higher than previously reported.

Targeting myelin lipid metabolism as a potential therapeutic strategy in a model of CMT1A neuropathy.

In patients with Charcot-Marie-Tooth disease 1A (CMT1A), peripheral nerves display aberrant myelination during postnatal development, followed by slowly progressive demyelination and axonal loss during adult life. Here, we show that myelinating Schwann cells in a rat model of CMT1A exhibit a developmental defect that includes reduced transcription of genes required for myelin lipid biosynthesis. Consequently, lipid incorporation into myelin is reduced, leading to an overall distorted stoichiometry of myelin proteins and lipids with ultrastructural changes of the myelin sheath. Substitution of phosphatidylcholine and phosphatidylethanolamine in the diet is sufficient to overcome the myelination deficit of affected Schwann cells in vivo. This treatment rescues the number of myelinated axons in the peripheral nerves of the CMT rats and leads to a marked amelioration of neuropathic symptoms. We propose that lipid supplementation is an easily translatable potential therapeutic approach in CMT1A and possibly other dysmyelinating neuropathies.

Directional flow induced by synchronized longitudinal and zeta-potential controlling AC-electrical fields.

Electroosmotic flow (EOF) in a microchannel can be controlled by electronic control of the surface charge using an electrode embedded in the wall of the channel. By setting a voltage to the electrode, the zeta-potential at the wall can be changed locally. Thus, the electrode acts as a "gate" for liquid flow, in analogy with a gate in a field-effect transistor. In this paper we will show three aspects of a Field Effect Flow Control (FEFC) structure. We demonstrate the induction of directional flow by the synchronized switching of the gate potential with the channel axial potential. The advantage of this procedure is that potential gas formation by electrolysis at the electrodes that provide the axial electric field is suppressed at sufficiently large switching frequencies, while the direction and magnitude of the EOF can be maintained. Furthermore we will give an analysis of the time constants involved in the charging of the insulator, and thus the switching of the zeta potential, in order to predict the maximum operating frequency. For this purpose an equivalent electrical circuit is presented and analyzed. It is shown that in order to accurately describe the charging dynamics and pH dependency the traditionally used three capacitor model should be expanded with an element describing the buffer capacitance of the silica wall surface.

The value of FDG-PET and bone scintigraphy with SPECT in the primary diagnosis and follow-up of patients with chronic osteomyelitis of the mandible.

OBJECTIVE: To appraise the value of FDG-PET and bone scintigraphy using SPECT in the primary diagnosis and follow-up of patients with chronic osteomyelitis of the mandible (COM). METHODS: In a prospective study the pattern of tracer uptake was investigated using 2 diagnostic methods in 42 patients. Results were compared with histology and radiographs as well as clinical and laboratory parameters. RESULTS: The use of FDG-PET in the primary diagnosis of COM resulted in a sensitivity of 64% and a specificity of 77.7%. The sensitivity of SPECT was 84% and the specificity 33.3%. During the follow-up period of these patients the sensitivity of SPECT increased to 93.7%, while the specificity decreased (6.6%). The sensitivity and specificity of FDG-PET for this follow-up group were 62.5 and 80%, respectively. CONCLUSION: Because of its high sensitivity, SPECT is vastly superior to other diagnostic methods in initiating treatment. In the follow-up period it might be replaced by FDG-PET, which reflects the disease course better and indicates the time of clinical remission.

Exposure of implants using a modified multiple-flap transposition vestibuloplasty.

AIM: To introduce a minimally invasive operation to improve the condition of the soft tissues around the implants in an atrophied mandible, at the same time, as uncovering the implants. PATIENTS AND METHOD: A multiple-flap transposition vestibuloplasty was done in 11 patients after the insertion of four implants in the interforaminal region of an atrophied mandible. Improvement in soft tissues and successful exposure of implants and attached gingiva were evaluated during a follow-up period of 55 months. All the patients were operated on local anaesthesia as outpatients. RESULTS: Adequate exposure of implants and an area of attached gingiva 4-9 mm wide were attained. There was no bleeding on probing or local infection. CONCLUSION: The transposition multiple-flap vestibuloplasty is a simple and minimally invasive method of improving the condition of soft tissue after insertion of implants. It does not limit the patients' routine activities and avoids staged operations.

Neonatal paracetamol treatment reduces long-term nociceptive behaviour after neonatal procedural pain in rats.

BACKGROUND: Pain from skin penetrating procedures (procedural pain) during infancy in the neonatal intensive care unit (NICU) may result in changes of nociceptive sensitivity in later life. This supports the need for pain management during such vulnerable periods in life. This study, therefore, analyses the short- and long-term consequences of neonatal paracetamol (acetaminophen) treatment on pain behaviour in an experimental rat model of neonatal procedural pain. METHODS: A repetitive needle-prick model was used, in which neonatal rats received four needle pricks into the left hind paw per day from postnatal day 0 to day 7 (P0-P7). Paracetamol (50 mg/kg/day s.c.) was administered daily (P0-P7), and sensitivity to mechanical stimuli was compared with a needle-prick/saline-treated group and to a tactile control group. At 8 weeks of age, all animals underwent an ipsilateral paw-incision, modelling postoperative pain, and the duration of hypersensitivity was assessed. RESULTS: Neonatal paracetamol administration had no effect upon short-term mechanical hypersensitivity during the first postnatal week or upon long-term baseline sensitivity from 3 to 8 weeks. However, neonatal paracetamol administration significantly reduced the postoperative mechanical hypersensitivity in young adults, caused by repetitive needle pricking. CONCLUSION: Paracetamol administration during neonatal procedural pain does not alter short-term or long-term effects on mechanical sensitivity, but does reduce the duration of increased postoperative mechanical hypersensitivity in a clinically relevant neonatal procedural pain model. WHAT DOES THIS STUDY ADD: Paracetamol can be used safely in neonatal rats. Neonatal paracetamol treatment had no effect upon short-term mechanical hypersensitivity during the first postnatal week, nor upon long-term baseline sensitivity from 3 to 8 weeks. Paracetamol treatment during the first postnatal week significantly reduced the postoperative mechanical hypersensitivity in young adult rats.

Spectro-temporal characteristics of single units in the auditory midbrain of the lightly anaesthetised grass frog (Rana temporaria L.) investigated with tonal stimuli.

Responses were obtained from 112 auditory neurons in the midbrain of the grass frog in response to sequences of tones. Their spectro-temporal sensitivities (STS) were determined by a second-order cross-correlation technique. For the majority of units the shape of their action potentials, the degree of timelock to the stimulus and the recording sites were obtained. Two stages of information processing could be distinguished. One was characterized by short latencies (less than 30 ms), strong timelock to the stimulus and many of these units had axon-like action potential waveforms. They were localised in the ventral part of the principal nucleus from the torus semicircularis and in the transition region between laminar and principal nucleus. The other stage comprised units, found all over the torus, with longer latencies, and a weaker timelock to the stimulus. Several units which were predominantly found in the central part of the torus, especially the magnocellular nucleus, showed a broad or multiple STS. Within the principal nucleus a weak tonotopy was found, the dorsoposterior part being sensitive to lower frequencies, the ventroanterior part to the higher frequencies. Binaural-interaction properties are discussed with respect to the eardrum coupling through the mouth cavity. An organisational plan for the torus semicircularis is proposed.

Spectro-temporal characterization of auditory neurons: redundant or necessary.

For neurons in the auditory midbrain of the grass frog the use of a combined spectro-temporal characterization has been evaluated against the separate characterizations of frequency-sensitivity and temporal response properties. By factoring the joint density function of stimulus intensity, I (f, t), preceding a spike, into two marginal density functions I1(f) and I2(t) one may under the assumption of statistical independence reconstruct the joint density by multiplication: I1(f).I2(t). The reconstructed I(f, t) is compared to the original I(f, t) for 83 neurons: in 23% thereof the I(f, t) appeared to be vastly different from I(f, t). These units appeared to be located dominantly in the ventral parts of the auditory midbrain and had a latency exceeding 30 ms. On the basis of the action-potential wave forms the absence of non-separable I(f, t) in the incoming nerve fiber population is concluded. A spectro-temporal characterization of auditory neurons seems mandatory for investigations in and central from the auditory midbrain.

Spectro-temporal characteristics of single units in the auditory midbrain of the lightly anaesthetised grass frog (Rana temporaria L) investigated with noise stimuli.

About 30% of the auditory units in the midbrain of the lightly anaesthetised grass frog respond in a sustained way to stationary pseudorandom noise. This response is described by the spectro-temporal receptive field (STRF), the regions in the spectro-temporal domain where the average second-order functional of those parts of the stimulus ensemble that precede the action potentials differ from the average second-order functional of the stimulus ensemble. By means of the STRF frequency selectivity, postactivation suppression and lateral suppression can quantitatively be studied under one and the same experimental condition. Auditory units that respond to stationary noise are localised in those parts of the torus where fibres enter from the olivary nucleus. They are characterised by relatively short latencies to tones and probably represent the first information-processing stage in the torus semicircularis.

Characterization of a naturally occurring infection of a Mycoplasma gallisepticum house finch-like strain in turkey breeders.

An outbreak of Mycoplasma gallisepticum (MG) in commercial turkeys involving very mild clinical signs was difficult to confirm by routine methods. In the first part of this study (trial A), we conducted a bioassay to increase the likelihood of detecting MG. Susceptible turkeys were inoculated with sinus exudates from four different affected commercial turkey flocks. Turkeys were evaluated for clinical signs, as well as by serology and culture of tracheal swabs, at 21 and 42 days postchallenge. An MG isolate from one of the sinus exudates used for inoculation, designated K5054, was very similar to isolates from house finches when characterized by random amplified polymorphic DNA analysis as well as DNA sequence analysis of portions of the phase-variable putative adhesin protein (pvpA) gene, a lipoprotein gene, and the cytadhesin gapA/mgc1 gene. The turkeys inoculated with the K5054 sinus exudate seroconverted in the absence of severe clinical signs. There was a single reisolation of K5054 from these turkeys 42 days postchallenge. Susceptible contact turkeys were commingled with the K5054-inoculated turkeys at 49 days postchallenge. We found no evidence of transmission of MG to the contacts by culture or serology at 7, 21, or 35 days after commingling. In the second part of this study (trial B), we challenged the contacts and K5054 sinus exudate-inoculated turkeys from trial A with virulent R strain 88 days after the K5054 sinus exudate inoculation. On necropsy 10 days postchallenge, the evaluation of gross and microscopic lesions, serology, and culture showed that the turkeys previously inoculated with K5054 sinus exudate were protected against disease and reinfection.

Subcutaneous fat layer in different donor regions used for harvesting microvascular soft tissue flaps in slender and adipose patients.

The aim of this study is to provide valid data concerning the thickness of the subcutaneous fat layer in seven donor regions which are most commonly used for soft tissue replacement in the head and neck region. Furthermore the study focuses on differences in thickness of this layer depending on the nutritional status and sex. In 100 volunteers the thickness of the subcutaneous fat layer was evaluated using ultrasound in seven potential donor regions: radial and ulnar forearm, lateral upper arm, scapular and parascapular region, abdominal/supra-umbilical region and the lateral calf. Volunteers were divided into 4 groups: male and female, slender (body mass index [BMI] < 25) and adipose (BMI > 30). Data obtained was compared and differences were proven to be statistically significant (Student's t-test, P<0.05). The largest thickness was found in the supra-umbilical region followed by the lateral upper arm whereas the ulnar forearm region had the smallest thickness. Depending on the BMI the supra-umbilical and the lateral upper arm regions showed the most wide variation. Depending on sex the most noticeable variation in thickness of the subcutaneous layer was seen in the lateral calf region with a significant larger tissue layer in females.

Auditory and visual similarity of pitch contours.

It has been shown that visual display systems of intonation can be employed beneficially in teaching intonation to persons with deafness and in teaching the intonation of a foreign language. In this paper, the question is addressed whether important audible differences between two pitch contours correspond with visually conspicuous differences between displayed pitch contours. If visual feedback of intonation is to be effective in teaching situations, such correspondence must exist. In two experiments, phoneticians rated the dissimilarity of two pitch contours. In the first experiment they rated the two pitch contours auditorily (i.e., by listening to two resynthesized utterances). In the second, they rated the same two pitch contours visually (i.e., by looking at the two contours displayed on a computer screen). The results indicate why visual feedback may be very effective in intonation training if pitch contours are displayed in such a way that only auditorily relevant features are represented.

Measuring the perceptual similarity of pitch contours.

It has been shown that visual display systems of intonation can be employed beneficially in teaching intonation to persons with deafness and in teaching the intonation of a foreign language. In current training situations the correctness of a reproduced pitch contour is rated either by the teacher or automatically. In the latter case an algorithm mostly estimates the maximum deviation from an example contour. In game-like exercises, for instance, the pupil has to produce a pitch contour within the displayed floor and ceiling of a "tunnel" with a preadjusted height. In an experiment described in the companion paper, phoneticians had rated the dissimilarity of two pitch contours both auditorily, by listening to two resynthesized utterances, and visually, by looking at two pitch contours displayed on a computer screen. A test is reported in which these dissimilarity ratings were compared with automatic ratings obtained with this tunnel measure and with three other measures, the mean distance, the root-mean-square (RMS) distance, and the correlation coefficient. The most frequently used tunnel measure appeared to have the weakest correlation with the ratings by the phoneticians. In general, the automatic ratings obtained with the correlation coefficient showed the strongest correlation with the perceptual ratings. A disadvantage of this measure, however, may be that it normalizes for the range of the pitch contours. If range is important, as in intonation teaching to persons with deafness, the mean distance or the RMS distance are the best physical measures for automatic training of intonation.

Safe out-of-hospital treatment of chest pain without direct medical control.

INTRODUCTION: The use of direct medical control (DMC) in the out-of-hospital setting often is beneficial, but has the disadvantage of consuming emergency medical services (EMS) resources. HYPOTHESIS: Uncomplicated, nontrauma, adult patients with chest pain can be treated safely and transported by paramedics without DMC. METHODS: Retrospective chart review of all nontrauma, adult patients with chest pain treated in a combined rural and suburban EMS system during a 2-year period (December 1990 through November 1992) was conducted. Before November 1991, DMC was mandatory for all patients with chest pain. Beginning 01 November 1991, if a patient had resolution of a pain either spontaneously, with administration of oxygen, or after a single dose of nitroglycerin, DMC was at the discretion of the paramedic. Using the above criteria for inclusion, three study groups were defined: Group 1, before protocol change; Group 2, after protocol change without DMC; and Group 3, after protocol change when physician contact was obtained, but not required. These groups were compared for the following parameters: 1) scene time; 2) time to administration of first dose of nitroglycerin; 3) time interval between measurement of vital signs; 4) oxygen use; 5) intravenous access; and 6) electrocardiographic monitoring. Continuous and categorical variables were analyzed by multivariate and univariate analysis of variance and chi-square tests, respectively. RESULTS: Of 308 nontrauma, adult patients with chest pain, 71 met inclusion criteria in Group 1, 40 in Group 2, and 34 in Group 3. No statistically significant differences were identified in any of the study parameters. CONCLUSION: Adult patients with chest pain who have no other symptoms or complicating conditions can be treated appropriately be paramedics without DMC.

Task-free electrocorticography frequency mapping of the motor cortex.

OBJECTIVE: Electrocortical stimulation mapping (ESM) is the current gold standard for functional mapping of the eloquent cortex prior to epilepsy surgery. The procedure is, however, time-consuming and quite demanding for patients. Electrocorticography frequency mapping (ECoG mapping) has been suggested as an adjunct method. Here, we investigated whether it is possible to perform mapping of motor regions using ECoG data of spontaneous movements. METHODS: Using the video registration of seven epilepsy patients who underwent electrocorticography and ESM, we selected periods of spontaneous hand and arm movements and periods of rest. Frequency analysis was performed, and electrodes showing a significant change in power (4-7, 8-14, 15-25, 26-45 or 65-95 Hz) were compared with those being identified as relevant for hand and/or arm movement by ESM. RESULTS: All frequency bands showed a high specificity (>0.80), and the 65-95 Hz frequency band additionally had a high sensitivity (0.82) for identifying ESM positive electrodes. CONCLUSIONS: Our data show a good match between ECoG mapping of spontaneous movements and ESM data. SIGNIFICANCE: The accurate match suggests that ECoG mapping of the motor cortex using spontaneous movements may be a valuable complement to ESM, especially when other options requiring patient cooperation fail.

Geo-environmental zoning using physiographic compartmentalization: a proposal for supporting sustainable decision-making

ABSTRACT The geo-environmental zoning represents an important strategy in the territorial management. However, it requires a logical and structured procedure. Therefore, an approach using physiographic compartmentalization is proposed and applied as case study in a region covered by the topographic maps of São José dos Campos and Jacareí, Brazil. This region has great geological and geomorphological peculiarities, beyond being a place with large human interventions because of its quickly economic growth. The methodology is based on photointerpretation techniques and remote sensing in GIS environment. As a result, seven geo-environmental zones were obtained from a weighted integration by multicriteria analysis of physiographic units with land-use classes. In conclusion, taking into account potentialities and limitations, the proposed approach can be considered able to support sustainable decision-making, being applicable in other regions.

The effects of blood vessels on electrocorticography.

Electrocorticography, primarily used in a clinical context, is becoming increasingly important for fundamental neuroscientific research, as well as for brain-computer interfaces. Recordings from these implanted electrodes have a number of advantages over non-invasive recordings in terms of band width, spatial resolution, smaller vulnerability to artifacts and overall signal quality. However, an unresolved issue is that signals vary greatly across electrodes. Here, we examine the effect of blood vessels lying between an electrode and the cortex on signals recorded from subdural grid electrodes. Blood vessels of different sizes cover extensive parts of the cortex causing variations in the electrode-cortex connection across grids. The power spectral density of electrodes located on the cortex and electrodes located on blood vessels obtained from eight epilepsy patients is compared. We find that blood vessels affect the power spectral density of the recorded signal in a frequency-band-specific way, in that frequencies between 30 and 70 Hz are attenuated the most. Here, the signal is attenuated on average by 30-40% compared to electrodes directly on the cortex. For lower frequencies this attenuation effect is less pronounced. We conclude that blood vessels influence the signal properties in a non-uniform manner.