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In recent years, image acquisition of process variables has become a common practice as an essential monitoring tool for industrial systems. The rise of data analysis models and high performance computers enables the development of systems to support real time decision and automation initiatives. This work aimed to develop a comprehensive methodology to acquire, process and interpret shale shaker video images to support detection of problems associated with poor hole cleaning and wellbore instability. To achieve this goal, experiments in different operational conditions were performed in a pilot-scale vibrating screen using a sand suspension with xanthan gum at 0.1% to emulate the slurry flow in actual sieves. Such experiments aimed to evaluate how some of the main operational variables influence the area of the sieve filled with solids, the moisture content of the solids, and their flow velocity. The proposed methodology used a U-Net convolutional neural network to perform the semantic segmentation of the sieve’s images to estimate the percentual area filled with solids in the shale shaker. An image database with 11,140 pictures and their respective templates was created from 26 experiments. The templates were built using image processing techniques, and 75% of them were used for training, 10% for validation, and 15% for testing. The neural network evaluation metrics were accuracy for training, F1-Score, and MeanIoU for testing. In addition, the estimated values were compared to the experimental data. The estimated velocity, expressed in cm/s, was further compared to experimental data. The results obtained using the U-Net showed high segmentation ability, with an average accuracy of 97%, mean F1-Score of 92%, and mean IoU of 91%. According to these results, it can be concluded that the proposed image-based technique is a promising tool for monitoring important process variables in drilling operations. Additional experiments with different shape particles result in effective guidelines to detect wellbore instability events. In future work, the authors expect to improve the segmentation technique to obtain better estimations of the process variables and the implementation of the procedure in integrated real time diagnosis systems. This work shows an innovative approach to support the drilling process, allowing to evaluate, quantify and characterize the drilling cuttings that returns to the surface. This initiative is committed to helping to reduce the well construction costs, non-productive times (NPTs) and to guarantee drilling operations more efficient and safer. Besides, provides additional relevant information to support the future views of autonomous drilling and unmanned rigs.

Background Understanding the complexity of the vine plant’s response to water deficit represents a major challenge for sustainable winegrowing. Regulation of water use requires a coordinated action between scions and rootstocks on which cultivars are generally grafted to cope with phylloxera infestations. In this regard, a genome-wide association study (GWAS) approach was applied on an ‘ad hoc’ association mapping panel including different Vitis species, in order to dissect the genetic basis of transpiration-related traits and to identify genomic regions of grape rootstocks associated with drought tolerance mechanisms. The panel was genotyped with the GrapeReSeq Illumina 20 K SNP array and SSR markers, and infrared thermography was applied to estimate stomatal conductance values during progressive water deficit. Results In the association panel the level of genetic diversity was substantially lower for SNPs loci (0.32) than for SSR (0.87). GWAS detected 24 significant marker-trait associations along the various stages of drought-stress experiment and 13 candidate genes with a feasible role in drought response were identified. Gene expression analysis proved that three of these genes (VIT_13s0019g03040, VIT_17s0000g08960, VIT_18s0001g15390) were actually induced by drought stress. Genetic variation of VIT_17s0000g08960 coding for a raffinose synthase was further investigated by resequencing the gene of 85 individuals since a SNP located in the region (chr17_10,497,222_C_T) was significantly associated with stomatal conductance. Conclusions Our results represent a step forward towards the dissection of genetic basis that modulate the response to water deprivation in grape rootstocks. The knowledge derived from this study may be useful to exploit genotypic and phenotypic diversity in practical applications and to assist further investigations.

Grapevine rootstocks affect the nutritional status of plants and thus the production and the quality of grape. In this study, a screening of mineral level in vine leaves is performed to a series of 35 Vitis hybrids for rootstock selection, in two different growing conditions at two sampling times. Mineral levels were determined by elemental analyzer (N) and ICP-MS (P; K; Mg; Ca; Na; Fe; Cu; Fe) in leave samples. Generally, the effect of growing conditions was predominant, whereas genotype effect and their interaction were significant for N, K, Ca, Mg, Na, Mn and Cu. A cluster analysis was used to identify the affinity of each genotypes to K, Mg and Ca. Furthermore, response of genotypes to the different environments was assessed by a plasticity index. An elastic behavior was shown by 14 genotypes. Within this group, genotypes G.05, G.21, G.71, G.76 and G.77 reported high potassium level, beside the already demonstrated tolerance to water stress.

Recent and severe droughts in major grape (Vitis)-growing regions of the United States and Australia underscore the importance of more efficient agricultural use of water. Grape rootstock breeding for increased drought tolerance could contribute to continued sustainable yields as fresh water supplies decline. Rhizotron containers were used in a greenhouse to investigate the predictive measures of drought tolerance in young grapevine rootstocks. Deeper rooting distributions were found for the drought-tolerant rootstocks ‘110R’ (Vitis berlandieri × Vitis rupestris) and ‘Ramsey’ (Vitis champinii, a natural hybrid of Vitis candicans × V. rupestris) as opposed to shallower distributions observed in the more drought-sensitive rootstocks ‘101-14Mgt’ (Vitis riparia × V. rupestris) and ‘Riparia Gloire’ (V. riparia). Production of new roots during a 6-day nonirrigated period declined 45% to 53% for ‘Riparia Gloire’ and ‘101-14Mgt’, respectively, but showed no change in ‘110R’ and ‘Ramsey’. Slow growth, a hallmark of abiotic stress tolerance, was evident in the drought-tolerant rootstocks in their relatively slow shoot growth before drought stress and their relatively slow new root growth during recovery, especially for ‘Ramsey’. High stomatal conductance (gS) corresponded with drought tolerance and distinguished rootstocks best during the first 3 days of recovery, with a mean value for ‘Ramsey’ 2.7 times higher than ‘101-14Mgt’. Stomatal conductance during recovery may serve as the most efficient means of predicting drought tolerance capacity in a breeding program.

Water availability is an important environmental factor in viticulture. In a climate change context, vineyard management should be adapted to the new conditions. Drought-resistant rootstocks need to be selected. In this paper, refectance spectroscopy is proposed as a new method to characterize the water stress efects on woody section pigmentations. Cabernet Sauvignon grafted on 4 diferent rootstocks (140Ru, 420A, M2 and M3) represented the plant material. Greenhouse controlled conditions allowed the comparison of well-watered (WW) and water-stressed (WS) plants. The physiological responses were characterized concerning daily water consumption, stem water potential, gas exchange, and plant growth. The water use eficiency was calculated and discussed as well. Spectroscopy analyses of woody sections indicated a major absorption band probably related to phenolic derivatives. Water stress produced characteristic spectrum modifications both in the Cabernet Sauvignon stem and in the rootstock xylem. These preliminary results encourage further studies addressed at the evaluation of drought-resistant genotypes, to distinguish their stress responses and to characterize the compositional aspects linked to drought tolerance.

Predicting ocean transport has many practical applications ranging from search and rescue operations to predicting the spread of oil, debris, and biogeochemical tracers, yet trajectory prediction remains a challenge for existing ocean modeling techniques. General circulation models require high resolution observational data in order to be properly initialized, but these data do not exist for the ocean. Statistical models are difficult to tune with existing data and are often too simple to accurately encapsulate turbulent flows. Here we investigate a data-driven approach to ocean transport prediction wherein the goal is to first learn from available data instead of prescribed laws of physics and then apply this information to new data. More specifically, we explore whether simple artificial neural networks (ANNs) are capable of learning to predict 2D particle trajectories using only previous velocity observations. ANNs are trained in two ways: first, a so-called “one-to-one ANN” uses a particle’s most recently observed velocity to predict its velocity six hours later, and second, a “time series ANN” uses the past 24 hours’ worth of velocity observations to predict the next 24 h. We present a proof-of-concept considering particles in a hierarchy of simulated flow regimes ranging from uniform, steady flow to more complex scenarios with interacting scales of motion and then substantiate our approach on trajectories in modeled flows generated by a high-resolution Hybrid Coordinate Ocean Model for a mesoscale eddy in the northern Gulf of Mexico. We also assess ANN sensitivity to the prediction window over which forecasts are made, the number of training particles used, and the size of the network. ANNs successfully predict 24 h trajectories within the temporal bounds of the training data with forecast errors around half those of both rudimentary persistence and classical ARIMA models. Predicting beyond the domain of the training data leads to forecast errors comparable to ARIMA models. Our results suggest that ANNs offer promising potential as a data-driven approach to forecasting material transport in the ocean.

Drought in grapevine could be faced using tolerant rootstocks. The present work aims at the evaluation of 25 new genotypes potentially tolerant to drought by using recent methods of phenotypical screening (thermography and on-solid reaction spectroscopy). Plants were grown in well-watered and stressed field conditions. Proxi for transpiration, wood hydrophobicity and starch content were used to characterize and classify the genotypes. The predominant role of the environment was highlighted, nevertheless genotype and genotype × environment interaction showed significant variations as well. Hybrids were classified based on their steady, susceptible or adaptable behavior. The 14 most promising genotypes were identified, 5 of them showing two tolerance mechanisms. In the future, results from this experiment will support viticulture in water limited areas releasing new drought-tolerant interspecific hybrids to be tested after grafting with different scions.

Changes in the performance of genotypes in different environments are defined as genotype × environment (G×E) interactions. In grapevine (Vitis vinifera), complex interactions between different genotypes and climate, soil and farming practices yield unique berry qualities. However, the molecular basis of this phenomenon remains unclear. To dissect the basis of grapevine G×E interactions we characterized berry transcriptome plasticity, the genome methylation landscape and within-genotype allelic diversity in two genotypes cultivated in three different environments over two vintages. We identified, through a novel data-mining pipeline, genes with expression profiles that were: unaffected by genotype or environment, genotype-dependent but unaffected by the environment, environmentally-dependent regardless of genotype, and G×E-related. The G×E-related genes showed different degrees of within-cultivar allelic diversity in the two genotypes and were enriched for stress responses, signal transduction and secondary metabolism categories. Our study unraveled the mutual relationships between genotypic and environmental variables during G×E interaction in a woody perennial species, providing a reference model to explore how cultivated fruit crops respond to diverse environments. Also, the pivotal role of vineyard location in determining the performance of different varieties, by enhancing berry quality traits, was unraveled.

The work aims at the description of the iron deficiency symptoms in grapevine leaves by reflectance spectroscopy at the plant and leaf levels. 5 genotypes of Vitis spp. were selected and grown in hydroponic conditions with and without iron supply. 450 spectra were collected among basal, young and apical leaves, as well as veins and interveinal areas. Iron deficiency produced significant and characteristic modifications in the pigment accumulation, proportion and distribution in plants. Basal leaves resulted to have higher concentrations of photosynthetic pigments in stressed plants with respect to the control, probably due to compensation effects. Iron deficient plants had lower chlorophyll concentrations in young and apical leaves. In the apical zone, also the relative composition of pigments appeared to be modified, explaining the reddish-yellowish apex appearance of iron deficient vines. Finally, the pigment distribution along the shoot characterized the symptoms, as well as the spectral variations among veins and interveinal areas. These results could support future applications in vineyard management (e.g.: symptom identification and detection; precision fertilization) as well as breeding programs for new rootstock selections (e.g.: fast screenings of seedlings).

Coastal salinity is a basic oceanographic property that is not routinely estimated by satellites. Efforts to measure ocean salinity from space are designed for large scale open ocean environments, not coastal regions. In the Mid-Atlantic coastal ocean, salinity is critical for understanding circulation patterns, river plumes, and transport, which in turn impact the status of the ecosystem. However, the spatial and temporal coverage of in situ salinity measurements in this region are sparse and do not synoptically capture salinity in the coastal ocean. We compiled ∼2 million salinity records from four regional research vessels between the years 2003–2008 and found ∼9 thousand salinity records that could be adequately matched to MODIS-Aqua data. We show that the spectral shape of water-leaving radiance and sea surface temperature are most correlated with in situ salinity. Four neural network models designed to predict salinity were developed for the Mid-Atlantic coastal region and three of its major estuaries (Hudson, Delaware, and Chesapeake). Our models predict salinity with RMS errors between 1.40 psu and 2.29 psu, which are much less than the null model ranges (4.87–10.08 psu) and the natural range of the system (0–32 psu). Seasonal climatologies for the Chesapeake, Delaware, and Mid-Atlantic regions based on these models are fresher than the existing NODC climatologies. We also found significant freshening trends in the Mid-Atlantic over a 6 year period.

Together with stomatal conductance and root conductivity, the stem water reserve and transport systems could be regulatory mechanisms able to participate in the regulation of the plant water status. Lianas, such as Vitis spp., minimize the trunk support role, and stems have evolved to improve their ability in water transport. In this work, stems of 10 different Vitis species were studied in relation to their expected drought tolerance using reflectance spectroscopy. Spectra were measured before (T0) and after coloration with Sudan IV dye. The T0 spectral signature showed characteristic species features. The partial least squares (PLS) regression and the self-organizing map (SOM) neural network analysis were able to predict the expected drought tolerance score; thus, reflectance spectroscopy was demonstrated to be a useful technique for drought tolerance phenotyping. These methods could be applied for the preliminary selection of new rootstocks/cultivars. Wood composition variation appeared to be correlated with the water stress susceptibility. To clarify this relationship, the attention was focused on the wood hydrophobicity. Sudan IV is a microscopy dye traditionally used to underline suberin, waxes, and, in general, hydrophobic substances. Differences between rough and colored spectra evidenced the absorption band of Sudan IV with a maximum at 539 nm. The coloration intensity was used to develop a hydrophobicity index. The obtained values were correlated with the expected drought tolerance score. Therefore, hydrophobic compounds seem to play an important role in water use efficiency, and an hydrophobic barrier in the xylem tissue appears to be a protective mechanism against water stress.

Background Echolalia is a verbal disorder, defined as 'a meaningless repetition of the words of others'. It is pathological, automatic and non-intentional behaviour, often observed in a variety of neurologi- cal and psychiatric disorders and above all in autism.We assume that echolalia is an imitative behaviour that is due to difficulties in inhibiting automatic repetition as seen in patients with frontal lobe damage. Our aim is to study the occurrence of echolalia under experimental conditions to investi- gate the nature of the phenomenon and its relation- ship with the severity of autism. Methods Eighteen participants with autism from 17 to 36 years old were recruited; they were adminis- trated the Vineland scale, the Observational Rating Scale of Basic Functions and the Echolalia Ques- tionnaire. In the Echolalia Questionnaire, questions were directly addressed to the autistic subject (induced procedure) or to the subject's caregiver while the subject was free to do what he wanted (incidental procedure).The data were analysed by multivariate regressions and Pearson's correlations. Results The results showed that echolalia occurred in both experimental situations; the mean value was significantly higher in the induced procedure, but results did not support the correlation with Vine- land's score in the incidental procedure. It is likely that the two situations activated different processes. In particular, echolalia was statistically higher in the induced procedure as compared with the incidental one only for subjects with low score on Vineland, but in the incidental procedure, the presence of echolalia appeared to be uninfluenced by the functional capacity of subjects. Conclusions The two experimental conditions require different monitoring systems to control this verbal behaviour.The echolalic phenomenon is an expression of dependence on the environment and may occur in a situation in which the autistic person is participating in a communicative act and, lacking inhibitory control, repeats the other's com- munication rather than selecting an answer.The deficit in inhibitory control in this situation does not seem to be present in subjects with higher effi- ciency. Incidental echolalia reflects the inability of the subject to filter out background environmental noise, which occasionally results in environmental dependency.

Mutations in Progranulin (PGRN) gene have been genetically associated with fronto-temporal dementia (FTD), although the neurobiology of this secreted glycoprotein is still unclear. We identified three familial cases having a rare +5 deletion in exon six of PGRN gene (g.101349_101355delCTGCTGT) as causative of frameshift mutation. This mutation is not considered frequent and already described in two apparently sporadic case of FTD only, but never associated with familial cases. Our patients showed also heterogeneous clinical phenotypes, such as behavioral variant (bv-FTD) in men and primary progressive aphasia (PPA) in women. Quantitative RT-PCR of PGRN gene expression in WBC shows an unusual increasing of expression, while protein analyses of plasma concentration detected a PGRN protein deficiency. Using allele-specific PCR mutation-primers (ARMS), this mutation was searched in three hundreds healthy controls matched by age, sex and geographic regions and no deletion was ever found. The findings provide convincing evidence of the putative role of PGRN in the genetic etiology of FTD and show a link between FTD and ex 6-del PGRN mutations, which probably are more frequent than previously considered. The described mutation express two different gender linked phenotypes bv-FTD in men and PPA in women. Although we believe that this is the product of a founder effect, we yet cannot prove at this stage. Our findings imply that PGRN is essential for neuronal survival and even partial loss of PGRN eventually leads to neurodegeneration.

In this work the radiation of the electromagnetic field due to partial discharges throughout the insulation spacer of Gas Insulated Switchgears is investigated. Radiation can be described in terms of resonant modes of the slot between the metallic bolts and of the parallel plate between the metallic flanges. The geometrical characteristics of the spacer, that contribute to the emission of power toward the environment, are investigated.

The relationship between logic and law has been a troublesome one and it has been object of much philosophical debate in the last century. Several scholars have denied the usefulness of logical methods in law and legal theory while others have strongly argued in favor of a logic-driven analysis of law and legal reasoning. Be it as it may, this latter view has generated decades of interesting work at the interface of law, logic but also philosophy and articial intelligence, and this work is the object of the present chapter. The present chapter is devoted to a short and light-weighted overview of some signicant contributions in this field. The overview should by no means be considered exhaustive and just briefly considers some key issues selected by the authors.

The paper describes a free-fall facility, called enhanced g-zero, to be dropped from a balloon at an altitude of 40–45 km for testing the Equivalence Principle. The free-fall duration is 30 s for a non-propelled capsule. Present estimates indicate that this facility provides an acceleration noise, away from the walls of the evacuated capsule, not to exceed 10−12 g during the fall. The envisaged technique for testing the Equivalence Principle involves the measurement of differential accelerations between two test masses of different materials that are part of a high-sensitivity detector. The detector is housed inside an instrument package cooled at the temperature of liquid helium. This package is first spun about a horizontal axis at a frequency of typically 1 Hz, for providing gyroscopic stabilization and modulating the gravity signal, and then released inside the falling capsule. The estimated accuracy in testing the Equivalence Principle, with 95% confidence level, is 5 parts in 1015 in a 30-s free fall.

Both sensory and imaginal defects have been reported in unilateral neglect, but their assessment based on the description of famous squares can be difficult in a clinical setting. The O'clock Test is an alternative tool for revealing imaginal defects. Our aim was to demonstrate imaginal neglect in patients with left heminattention. Ten patients were studied and a mild unilateral defect in imaginal processes was found with an increase in the defect when the patients were fatigued.

Background Echolalia is a verbal disorder, defined as “a meaningless repetition of the words of others”. It is pathological, automatic and non-intentional behaviour, often observed in a variety of neurological and psychiatric disorders and above all in autism. We assume that echolalia is an imitative behaviour that is due to difficulties in inhibiting automatic repetition as seen in patients with frontal lobe damage. Our aim is to study the occurrence of echolalia under experimental conditions to investigate the nature of the phenomenon and its relationship with the severity of autism. Method Eighteen participants with autism from 17 to 36 years old were recruited; they were administrated the Vineland Scale, the Observational Rating Scale of Basic Functions (SVFB), and the Echolalia Questionnaire. In the Echolalia Questionnaire, questions were directly addressed to the autistic participant (induced procedure) or to the participant’s caregiver while the participant was free to do what he wanted (incidental procedure). The data were analyzed by Multivariate regressions and Pearson’s correlations. Results The results showed that echolalia occurred in both experimental situations; the mean value was significantly higher in the induced procedure, but results did not support the correlation with Vineland’s score in the incidental procedure. It is likely that the two situations activated different processes. In particular, echolalia was statistically higher in the induced procedure as compared with the incidental one only for participants with low score on Vineland, but in the incidental procedure, the presence of echolalia appeared to be uninfluenced by the functional capacity of participants. Conclusions The two experimental conditions require different monitoring systems to control this verbal behaviour. The echolalic phenomenon is an expression of dependence on the environment and may occur in a situation in which the autistic person is participating in a communicative act and, lacking inhibitory control, repeats the other’s communication rather than selecting an answer. The deficit in inhibitory control in this situation does not seem to be present in participants with higher efficiency. Incidental echolalia reflects the inability of the participant to filter out background environmental noise, which occasionally results in environmental dependency.

In this work a broadband UHF antenna with high inductive input impedance for radiofrequency energy harvesting is presented. It consists of a small feeding loop and a biconical radiating dipole. A prototype has been fabricated on a FR4 substrate and tested. Experimental results show a −3dB power transmission bandwidth of about 135MHz (840MHz–975MHz).

A 3-m-long, non-propelled cryostat released from a 40-km-high balloon is used to shield a detector free falling inside for 30 s. This facility provides opportunities for accurate experiments in gravitational physics. Among others, two experiments of particular interest are: (a) a free-fall test of the Equivalence Principle; and (b) the local mapping of the gravity field along vertical lines by means of as gravity gradiometer. In experiment (a), the differential accelerations between two test masses of different materials (e.g. aluminum and gold) is measured during free fall. The estimated accuracy in testing the Equivalence Principle in a 300-s free fall is 4 parts in 10 14 with 95% confidence level. In experiment (b), the knowledge of surface gravity anomalies can be improved with a 10 −2 -EU gradiometer and the upward continuation gravity models validated.

The calibration of EMC antenna has always been a frustrating subject for most EMC laboratories for various reasons. On the other hand in many cases EMC antennas are recalibrated when it is not strictly necessary. This paper proposes a procedure to establish when EMI antennas shall be calibrated on the basis of technical considerations without making reference to abstract quality assurance rules.

A general spectral domain formulation to the problem of radiation of arbitrary distribution of sources embedded in a horizontally stratified arbitrarily magnetized linear plasma is presented. The fields are obtained in terms of electric and magnetic type dyadic Green's functions. The formulation is considerably simplified by using the kDB system of coordinates in conjunction with the Fourier transform. The distributional singular behavior of the various dyadic Green's functions in the source region is investigated and taken into account by extracting the delta function singularities. Finally, the fields in any arbitrary layer are obtained in terms of appropriately defined global upward and downward reflection and transmission matrices.

A long tether connects a Martian orbiter to a small probe orbiting in the dense atmosphere of the planet. The minimum altitude reachable by the probe is estimated based upon considerations of dynamic stability, tether temperature, resistance of the tether material, and propellant consumption required to maintain a constant orbital altitude. The results obtained by means of a static-force model are then verified by dynamics simulation carried out by using a lumped-mass computer code. The scientific applications of this tethered system include probing of the Martian upper atmosphere and gravity mapping of the planet carried out by collecting gradiometric data from the probe. Another application involves the release of Martian rovers and penetrators from the probe at low altitude.

In a preview study we found that luteinizing granulosa cells from follicles of patients with polycystic ovary syndrome (PCOS) have a reduced capacity to synthesize progesterone in vitro. Because the 3 beta-hydroxysteroid dehydrogenase/delta 5-delta 4-isomerase (3 beta-HSD) is an important enzyme for the biosynthesis of progesterone, the reduced capacity of PCO luteinizing granulosa cells to synthesize progesterone in vitro may be due to reduced 3 beta-HSD gene expression. A reverse transcriptase polymerase chain reaction for 3 beta-HSD was performed and the relative intensity of signals for 3 beta-HSD was evaluated using computer-assisted densitometry. Cells from polycystic ovaries expressed less 3 beta-HSD in folliclesor 10 mm (p0.05) and in folliclesor 16 mm (p0.05) than cells from normal ovaries. Furthermore, after human chorionic gonadotropin stimulus (50 ng/ml), cells from polycystic ovaries expressed less 3 beta-HSD in folliclesor = 16 mm (p0.01) than cells from normal ovaries. The data show that there is a specific change in the gene expression of 3 beta-HSD in PCO granulosa cells resulting in a suppressed capacity to secrete progesterone.

A technique for testing the weak-equivalence principle is presented. This technique involves the measurement of differential accelerations between two test masses of different materials (e.g., aluminum and gold) free falling inside a 3 m long cryostat dropped from a 40 km altitude balloon. The free-fall duration is 30 s for a non-propelled cryostat. The falling test masses are part of a high-sensitivity differential detector with a foreseeable sensitivity in detecting differential accelerations of about 1.5·10−13\(g/\sqrt {Hz} \) (at the liquid-nitrogen temperature of 77 K) and 1.5·10−14\(g/\sqrt {Hz} \) (at the liquid-helium temperature of 4 ). The detector is spun about a horizontal axis at a frequency of typically 1 Hz in order to modulate the gravity signal during free fall. The estimated accuracies, with 95% confidence level, in testing the weak-equivalence principle in a 30 s integration time are 5 parts in 1014 at the temperature of liquid nitrogen and 5 parts in 1015 at the temperature of liquid helium.

Many authors hypothesized a linkage between the anatomical region of damage and the nature of constructional apraxia. In particular, the functional impairment of right brain damaged patients should consist in a visuo-spatial defect. However a large amount of researches have showed impaired visuo-spatial abilities in apraxic subjects respect to non-apraxics, but independently by the side of brain damage. In these researches constructional and visuo-spatial abilities have been often evaluated by methods not comparable among them. Aim of this paper is to verify the constructional performances of left and right brain damaged patients, utilizing exclusively the copy of geometric figures and tasks considered specific in detecting visuo-spatial disabilities. The experimental results show that both left and right brain lesions produce impairments of visuo-spatial abilities. Lastly, the utility of a cognitive approach of study is discussed.

This study of a dyslexic patient supports the view that the level of impairment of the phonological route plays a role in the production of semantic paralexias. The patient's reading was based on a defective phoneme-to-grapheme transcoding, in spite of evidence that semantic information was available through non phonological routes. The hypothesis that the residual ability to carry out phonological recoding could block the production of semantic paralexias was confirmed by tachistoscopic reading, assumed to interfere with phonological recoding in this patient, that provoked a definite rise of this type of error. The relationship between the degree of damage of phonological route and the clinical expression of the syndromes of phonological dyslexia and deep dyslexia is also discussed.

This overview deals with the neuropsychology of memory. First cognitive models proposed for primary and secondary memory are reported, particularly the working memory theory and episodic/semantic distinction are discussed. Briefly the modern point of view about the anatomical bases of memory functions are reported with stressing above all the role of limbic structures. Lastly the pathology of both primary and secondary memory is dealt with, trying to abstract the clinical features of different syndromes.

This paper reports the clinical features of 2 patients affected by mixed transcortical aphasia. Both of them had extensive damage of the left hemisphere. Cerebral blood flow measurement showed a marked decrease in left-hemisphere flow. In particular, speech areas were found to be morphologically and functionally damaged. The present findings, together with a critical review of the literature, served as a starting point for a discussion of linguistic features, diagnostic criteria and classical neuroanatomical interpretation of mixed transcortical aphasia. The possible contribution of the right hemisphere in determining this aphasic syndrome is suggested.

Two hundred and seventy-nine consecutive patients referred for transient loss of consciousness, compatible with syncope, underwent head-up tilt to 70 degrees during polygraphic (EEG, ECG, pneumographic) and blood pressure monitorings. Vasovagal syncopes occurred in 28 patients with the following EEG changes: progressive slowing until the appearance of middle or high amplitude delta waves generalized and synchronous in 9 patients; delta waves suddenly followed by transient flattening of EEG activity in 16 patients. In 2 patients EEG could not be interpreted because of muscle and/or movement artifacts. Fifteen out of 28 patients exhibited a marked cardioinhibition, expressed by long-lasting cardiac pauses; a relationship between duration of EEG flat and duration of asystole was not found.

Spatial span (Corsi's block-tapping test) and verbal span (Wechsler's Digits Forward test) were measured in 651 normal subjects and in three groups of extrapyramidal patients (Progressive supranuclear palsy, Parkinson, and Huntington's Chorea). Analysis showed Huntington's Chorea patients scored lower on both tests than did controls and other groups.

Radio occultation measurements were made at approximately 50 locations on Mars with the Viking Orbiter 1 S (2.3 GHz) and X (8.4 GHz) band tracking links during October 1976. The measurements have been used to study the topography and atmosphere of Mars at latitudes ranging from about 75 deg S to 70 deg N. By using the ingress and egress times obtained from the observed limb diffraction effects together with the best ephemerides available for the orbiter and the planet we have determined the surface elevations at the occultation points relative to the reference areoid. The observations agree with Mariner 9 and radar data to within 2 km. The mean atmospheric pressure at the areoid level was found to be 5.9 mbar during the northern midsummer season, a value which agrees quite well with data obtained at the landing sites. By comparing the new electron density measurements with earlier Mariner data we have determined that the temperature and the plasma scale height of the upper atmosphere appear to be functions of solar activity.

For some time the possibility has been considered to perform an accurate survey from orbit of the earth gravity field by making use of low-low, satellite-to-satellite Doppler tracking with a radio link which operates in the frequency band in the range from 50 to 100 GHz. It is, therefore, of interest to discuss the upper bound in Doppler measurement accuracy imposed by the effects of ionospheric turbulence. The present investigation is concerned with the measurement error induced by ionospheric turbulence. The assumptin is made that the so-called ionospheric refractive 'bias' can be removed with one of the multifrequency methods of the current practice.

The Viking lander-to-orbiter relay links make it possible to perform measurements of the electrical properties of the Martian surface by the bistatic technique. The electromagnetic signals radiated by the lander antenna at 381 MHz, in fact, reach the orbiter both directly and after reflection from the Martian terrain as the orbiter rises and sets with respect to the lander. The fading pattern of the signal intensity received at the orbiter therefore contains information on the reflection coefficient of the terrain and hence on the relative dielectric constant er and the conductivity σ in the vicinity of the lander. The signal amplitude's fading patterns collected with the Lander 1 to Orbiter 1 relay link were of good quality and led to the determination of er = 3.3 ± 0.7 in the vicinity of Lander 1 (when the quasi-specular theory was used and σ was assumed to be between 10−3 and 1.0−5 mho/m). These electrical properties are similar to those of pumice and tuff. The dielectric constant of the surface near the Lander 2 site is estimated to be er = 2.8–12.5.