bluuebunny/crossref_metadata_2025 huggingface dataset:
High Voltage Fluorescent Tubes
Authors: Jenkins H. G. , Bowtell J. N.
Published: November 2015

It is the purpose of the present paper to draw attention to some of the special characteristics of high-voltage fluorescent tubes, with particular reference to the cold cathode type available in this country at the present time. Before dealing with the tubes themselves, the various types of cathodes used in high-voltage fluorescent tubes are discussed. This is followed by a brief account of the more important luminescent materials in common use for these tubes. The limitations of mercury-filled fluorescent tubes for producing very warm light and the advantages of neon fluorescent tubes for this purpose are discussed. Reference is made to the special features of high-voltage, hot-cathode fluorescent tubes
Photographic Illumination in Motion Picture Studios
Authors: Hauser F. V. , Hawkins F. S. , Stevens W. R.
Published: November 2015

The conventional method of lighting a motion picture set is described, together with the illumination levels needed and the spectral distribution of the light, and from these factors the general requirements are deduced for lighting fittings using tungsten filament, carbon arc and high pressure mercury vapour discharge lamps. A more detailed account is then given of the way in which each of these sources is employed in order to satisfy the general requirements. The design of prismatic lenses, external attachments for light control, efficiency and colour of high intensity arcs, the double negative arc, operational requirements of discharge lamps, and thermal and mechanical design problems are discussed. They show what is accepted good practice at the present time and where future development may occur. A short closing section on supplies for studio lighting discusses the effect of ripple in the electrical supply voltage on generating noise in the flame of a carbon arc.
New Lamp Developments
Authors: Harris N. L.
Published: November 2015

The history of electric lamp development has been one of steady improvement in the efficiency of production of light. The lamps used to-day for general lighting have 15 to 20 times the efficiency of those first developed some 70 years ago. This paper surveys recent achievements and indicates the probable lines of future developments. New types of carbon arc lamp are described. Filament lamps, on the whole, are unlikely to advance far beyond their present level of performance. (Discharge lamps, however, promise considerable development in various directions. Typical of progress in fluorescent lamps is the discovery of halophosphate phosphors giving white light from a single powder, having a high degree of chemical stability and already providing an improvement of more than 50 per cent in the average efficiency throughout life. Simplification of control gear and the rapid starting of lamps are other aspects under constant review and in which developments may be expected. High-pressure metal vapour lamps show improved colour-rendering properties, without loss of luminous efficiency, by the addition of cadmium and zinc vapours and the use of higher operating temperatures. They are already finding application in cinema and television studios and give promise of ultimate use in general lighting service. Other developments reviewed include high intensity flash discharge lamps for use in photographic studios, press photography, and similar work. The operating circuit can be adapted for using the lamps in stroboscopic examinations of moving machinery. Daylight colour matching fluorescent lamps and additions to the range of specialised discharge lamps used in laboratory work are also described.
Gas-Filled Discharge Tubes as Light Sources for High Speed Photography
Authors: Mitchell J. W.
Published: November 2015

This paper describes the development of high-intensity flash discharge tubes capable of giving light flashes with an effective photographic duration of less than 1.5 microseconds, which can be used for photographing high-velocity shells by reflected light. The properties and the limitations of flash discharge tubes in single flash and in multiple flash applications are discussed.
The Manufacture of Metal Parts for Lighting Fittings
Authors: Hartill P.
Published: November 2015

This paper briefly reviews some of the properties of metals which are of particular importance in the lighting industry and describes methods of shaping and finishing commonly used in current practice. Different kinds of protective treatment are discussed having regard both to resistance against corrosion and to maintenance of reflecting quality. Finally, some comparisons of performance are given for metal reflectors with various finishes and contours.
Specialised and General Lighting in Hospitals
Authors: Peirce M. W. , Reed D. J.
Published: November 2015

This paper discusses some of the lighting requirements in hospitals, and describes ways in which they are satisfied. The lighting of the operating theatre is considered in some detail and an attempt has been made to classify systems of lighting according to their suitability for different surgical operations.
The Operation and Maintenance of Fluorescent Lamp Installations
Authors: Stoyle W. A. R. , Jones-Thomas G. D.
Published: November 2015

Because of the many new ratings of lamps and new circuits, the operation and maintenance of fluorescent lamp installations has brought fresh responsibilities to the maintenance engineer. Effective maintenance requires fundamental knowledge of lamps and their associated circuits. This paper, therefore, deals with lamp and circuit characteristics from a practical point of view.

A detailed description of circuit components is also given, together with recommended testing methods and advice as to how troubles can be detected, identified and remedied.
The Control of Light by a Lighthouse Lens
Authors: Hampton W. M.
Published: November 2015

The conditions to be fulfilled by a lighthouse lens are briefly described and a short historical survey is made. Elementary theoretical requirements are discussed, with particular reference to the aberrations inherent in the use of glass lenses. Particulars are given of the various approximations which are necessary to make manufacture practicable and the methods used for calculating the axial intensity are described. Recent work on the factors controlling the conspicuity of such lights is discussed, including the Blondel-Rey correction for duration of flash. Methods for computing the range of a beam under various conditions are given, and the range is related to the Standard Visibility Code of the meteorological services. The practical application of these various features to typical lighthouses is described.
Luminescence as Applied to Lighting
Authors: Jenkins H. G. , McKeag A. H.
Published: November 2015

This paper deals with the main features of luminescence of interest to illuminating engineers. An account is given of the theoretical aspects of photoluminescence and the more important inorganic phosphors are mentioned. The factors which determine the luminous performance of both low and high pressure fluorescent lamps are discussed. Reference is made to a number of general matters concerned with luminescence, including the phenomena of electroluminescence.
Lighting in the Design of Schools
Authors: Pott Anthony
Published: November 2015

Changes in ideas on education, in teaching methods, in building techniques and in economic conditions are combining to produce new forms of school used in new ways. The importance of scale and character is becoming more widely appreciated and the newer teaching methods are demanding rooms which can be used for many different purposes.

The provision of natural and artificial lighting, adequate both in quantity and quality, for these new schools is discussed, and some recent installations and fittings are critically reviewed.
The Design of Interior Lighting Equipment
Authors: Hubble L. H.
Published: November 2015

The object of this paper is to record major developments in interior lighting equipment and in so doing to indicate the direction in which future developments are most likely to move. A short section is devoted to fittings in general use up to 1940 when the first impact of the fluorescent lamp was felt. The effective use of high-pressure mercury vapour lamps is considered and the value of horizontal burning lamps is emphasised.

After discussing some of the problems in the design of standard fluorescent fittings, with a particular reference to the complication caused by the many different types required, brief analyses are given of the lighting units required for some special types of installation.

For example, in a power station, the crane rail may be used as the main rigid structure for fluorescent lighting fittings built around it: commercial fittings have also been designed on this principle. Another interesting technique uses composite fittings of metal and plaster, since plaster can be formed easily and cheaply to a desired curvature.

The author believes that fundamental changes are now taking place in the mechanics of lighting practice, which may have a far-reaching effect on fittings design, but that progress may be hampered by too great complexity. Advances in lamps are inevitable and desirable, but every effort should be made to rationalise the design of lamps and components to assist the fittings maker in reducing some of the many variables in his equipment.
Colour in Schools
Authors: Medd David
Published: November 2015

The following is the opening contribution to a discussion on the Ministry of Education Building Bulletin No. 9 on Colour in Schools. After explaining the object of the Bulletin, the functions of the architect and lighting engineer in this field and the importance of colour on both aesthetic and functional grounds are discussed. Factors to be considered in the selection and use of appropriate colours are also discussed.
The Non-Additivity of Heterochromatic Brightnesses
Authors: Dresler A.
Published: November 2015

Although standard practice in up-to-date photometric laboratories shows that the expert is well acquainted with the intricacies of visual heterochromatic photometry, several recent publications on the non-additivity of heterochromatic brightnesses seem to indicate that the basic problems involved are not always fully understood by non-specialist photometrists. In this paper the author reviews the results of three independent investigations which all show that there is a definite, although non-linear relationship between the apparent brightness of surfaces of different colour and the photometric assessment of their brightness in terms of luminance as defined by the C.I.E. The general trend of this non-linear relationship between brightness and luminance is revealed and discussed. Finally, some suggestions are made how heterochromatic brightnesses can best be assessed visually in terms of their luminances.
The Meeting Beams of Headlights; Effects of Deterioration and Misaim
Authors: Harris A. J.
Published: November 2015

The most important factor in the design of the typical meeting beam of headlights, so far as the range of direct seeing is concerned, is the sharpness and form of the cut-off near the horizontal. But the effect which the cut-off will have on the likelihood of being dazzled, i.e., of being rendered incapable of seeing more than a short distance, when meeting other vehicles at night depends enormously on the accuracy with which meeting beams are aimed. The effect can be calculated when the standard of aiming is known; the basis of the calculation and some results are given in this paper. Curves are provided from which may be found the sharpness of cut-off required to give any desired level of freedom from dazzle. It is shown that if the standard of aiming is too low it will be impossible to design a beam to fulfil the required conditions. The necessary improvement in aiming can, however, be determined from the curves. The effect of deterioration in increasing the liability to dazzle is also considered. The pitching motion of the vehicle, and its effect on seeing distance and on intermittent glare, have had to be omitted from this analysis; the effect will be more important the sharper the cut-off employed.
Artificial Lighting for Plant Growth
Authors: Canham A. E.
Published: November 2015

Light is one of the major factors controlling plant growth. By the appropriate use of artificial light greater control over the growth and development of plants is possible. It is a complex subject and in this paper the effects of different light conditions are discussed. Applications of artificial light in research and commercial horticulture are also considered, together with the merits of different light sources for these purposes.
Lamps and Their Uses
Authors: Aldington J. N.
Published: November 2015

The design of a light source cannot be separated from its use. Increasingly in recent years has this fact influenced lamp development and research. Some of the factors of which account has to be taken in the evolution of new sources are mentioned. It is considered that the remarkably active phase of invention in the associated fields of metal vapour discharge lamps and fluorescent lamps is now merging into a period of consolidation characterised by the continuous improvement of existing types.

Following the basic classification used in the light source reports to the 1948 and 1951 Plenary Sessions of the C.I.E., certain special features of lamps for each group are described to illustrate their relation to user requirements. Mention is made of the special problems which arise in determining the optimum colour for fluorescent lamps for different uses.
Dark Adaptation and Miners' Nystagmus
Authors: Ferguson W. J. Wellwood
Published: November 2015

This paper is a report on the continuation of work on dark adaptation and miners' nystagmus referred to in a previous paper by the author.
Direct Flux, Inter-Reflections, and Final Luminances in Rectangular Rooms
Authors: Phillips R. O.
Published: November 2015

A method is developed from first principles for finding the average illumination on any surface of a rectangular room due to the luminances of the other surfaces. This method depends on the Hisano “room index,” k, and an associated function Pk, derived from the work of Yamauti, which is tabulated for a range of values of k. Illustrative examples show how it may be used to determine the direct flux required to produce a predetermined luminance pattern, or to reverse this procedure. Some comparisons are made between the results obtained by this method and by others, including direct measurement, and the agreement is shown to be generally satisfactory.
The Lighting of Standard Factories on a Trading Estate
Authors: McCulloch J. S.
Published: November 2015

After the depression in industry in the 1930s the Government passed the Special Areas (Development and Improvement) Act of 1934 and that led to the formation in May, 1936, of a company called the North Eastern Trading Estates Limited, with registered offices on the Team Valley Estate, Gateshead on Tyne. The Company acted as the agent for the Commissioner of Special Areas, to acquire and develop estates to attract light industries to the Area and so secure a better national distribution of industrial activity. There are now 35 estates in the North Eastern Development Area, housing over 300 tenants and giving employment in light industries to over 52,000 people.

In 1945 the Estate Company developed a Standard Factory of which large numbers were built on its estates. A standard lighting installation was developed to meet the requirements of the majority of prospective tenants, who connected various light sources to it. The annual cost of these lighting installations using different light sources is compared, taking into account the annual charges of wiring installation and fittings, replacement charges for lamps and cost of the electrical energy consumed. Some comments are made on the types of fittings used by the tenants.
Television Studio Lighting Equipment
Authors: Ackerman K. R.
Published: November 2015

The paper summarises the present state of development of lighting equipment for television studios in Great Britain, with particular reference to the studios of the B.B.C., and outlines the rapid progress which has been made in recent years in the mechanisation and flexible control of this equipment. This development has included improvements in mechanical handling of luminaires, the introduction of remote controlled dimming and switching systems, and improvements in studio luminaires themselves.

The difficulties in lighting a television production effectively are outlined and the paper shows how these difficulties can be minimised by equipment specifically designed for the purpose. The equipment used is shown to have developed logically from that designed for filming and for the stage, but modified to meet the special requirements of television.

Light sources are discussed and the paper shows that the tungsten lamp remains the most suitable for this application, though fluorescent lamps and carbon arcs are used for special purposes.
Visual Problems on Motorways
Authors: Waldram J. M.
Published: November 2015

The visual problems of drivers on the motorway have been studied by new techniques and compared with the problems on traffic routes, with special reference to the possible need for fixed lighting. By day the visual problems are generally much less severe on the motorways, but the vehicle and the driver have less in hand to cope with emergencies and consequences of an accident are often more grave. By night the information presented to the driver by headlights, reflector studs, rear lights and signals are found to be inadequate and often confusing. Fixed lighting of good quality has been shown to be capable of giving the driver all the information he needs, and it is concluded that a technical case for its installation can be made out. The accident rate on motorways is low at present traffic density, but on motorways abroad where the density is greater high accident rates occurred which have been substantially lowered by the installation of fixed lighting. Technical characteristics for fixed lighting on the motorway are derived from the observed requirements. The paper does not discuss questions of engineering, economics or policy. Some suggestions for guidance and visual signalling on the motorway are discussed in an appendix.
Pre-Determination of Direct Discomfort Glare
Authors: Einhorn H. D.
Published: November 2015

A formulation for the practical pre-determination of direct discomfort glare is proposed on the Harrison-Meaker pattern, but based on later laboratory research. A summation theorem is postulated, which states that a glare rating must be proportional to source area if simple additivity is desired. A location coefficient chart has been derived from Luckiesh-Guth's position indices, and αΛ-charts are given which allow for orientation as well as position of glare sources. An analytical expression for the location coefficient dispenses entirely with charts.
The Design of the Visual Field in Streets: The Visual Engineer's Contribution
Authors: Waldram J. M.
Published: November 2015

This paper extends the principle of the design of the visual field into the outdoor scene. The problems here are more difficult, mainly because streets are used for a great variety of activities with conflicting requirements; unless and until there is more effective segregation of them, effective design of the visual field is not possible. Current means of such segregation are briefly reviewed. The basis of design is outlined, and the problems associated with particular activities are discussed. It is stressed that good visual design must be in the hands of a single designer with powers to act, and that he must consider the whole perspective of the scene and the relation of the components to the whole. The most serious problems in present streets arise from their use as markets, especially at night from commercial lighting and signs, which seriously hinder road users from seeing the visual information which they need. Suggestions are made for practical means for restricting advertising signs in a way which will help drivers without seriously diminishing their advertising effectiveness. Signs for traffic are also discussed, and some suggestions for their improvement are made. Detailed solutions of problems of design of the outdoor visual field are not discussed.
Quality of Interior Lighting Based on Luminance
Authors: Bodmann H. W.
Published: November 2015

Several investigations on the influence of light upon human reactions with regard to perception and comfort of seeing have been made during past years; from the results of these studies, together with some new results and presentations, an attempt is made to analyse the problem of lighting quality in terms of luminance levels, luminance limits and luminance ratios. Brief consideration of related work in different countries leads to a common basis of similar results. In general visual performance and visual comfort depend on the luminance distribution in the visual field; the lighting engineer will therefore have to deal with the construction of an optimum luminance pattern as an integral part of environmental engineering.
Working and Living in a Luminous Environment
Authors: Crouch C. L.
Published: November 2015

Illuminating engineering is at a new horizon where it must think of the 'whole man'. It must specialize in designing the luminous environment but it must help integrate that environment with the thermal and sonic environments. Since it provides the medium for the greatest share of communication of knowledge and the circumstances for work (visual piloting) it should take the lead in study of the total impact on man.
Paints and Surface Coatings for Lighting Fittings
Authors: Rhind-Tutt A. J.
Published: November 2015

The use of organic coatings in the lighting fittings industry is reviewed and the need for the protection and decoration of a wide variety of materials of construction is considered. The properties of the various types of coatings, vitreous enamel, alkyds, acrylics, epoxies and pvc are outlined and their important properties listed.

Vitreous enamel coatings are now needed only in very corrosive or hot environments and most fittings are now coated with alkyd or acrylic based paints which have a life equal to that of the fitting itself. On-site painting methods are used when special effects, such as particular colours or resistance properties, are required. A summary of the types of paints commonly used on a range of typical fittings is included.
Breast Cancer Screening: A Social Marketing Study
Authors: Bryant Carol A. , Cole Stephen , Salazar Bonnie , Lindenberger James , Perrin Kay , Sorrell Connie , Flynn Michael , Courtney Anita , Dennis Carolyn , Markesbery Barbara A. , Gaskin Erin
Published: November 2015

Breast cancer is one of the leading types of preventable cancer among women in the United States. Despite improvements in mammography and early detection techniques for breast cancer, special population groups within the United States continue to experience high incidence and mortality rates. This paper focuses on Kentucky's underserved populations. The research objectives were to: 1) identify the factors that motivate women at risk to be screened for breast cancer; and, 2) identify the factors that deter women at risk from being screened for breast cancer.

A combination of quantitative (survey n=407) and qualitative (focus groups=19; in-depth interviews=58) research methods were used to examine factors that influence mammography use. Factors that motivate women to have mammograms include: physician referral; the belief that early detection will improve breast cancer outcomes; and, the belief that a mammogram is an effective test. Factors deterring women from having mammograms include: lack of physician referral; cost; and, the belief that mammography is dangerous.

Research findings point to the need for a comprehensive, integrated approach to increasing utilization rates. This approach includes recommendations for increasing physician referrals, modifying service delivery, training staff, and development of client education materials and a public information campaign. These recommendations have been incorporated into a social marketing plan to increase utilization of mammography services in the state of Kentucky.
“Finding” Payepot’s Moccasins
Authors: Sperlich Tobias , Brogden Lace Marie
Published: November 2015

Using altered readings of normative, “common sense” histories, this article illustrates diverse entry points into interpreting narratives, museums, and place. It queries ways in which colonial subjectivities can be (re)produced through museum objects, collections, and displays, as well as the social engagements collectors, benefactors, curators, visitors, and others might have with them. The article revolves around a late 19th-century pair of moccasins of First Nations provenance attributed to renowned Cree Leader, Chief Payepot, housed in a rural, community museum, the Jasper Cultural and Historical Centre. By examining both the physical and metaphorical positionalities of “Chief Payepot’s Moccasins” as they come to be represented through various texts and subtexts, we argue for a disruption of hegemonic settler narratives in the not-yet-post-colonial territory commonly known in contemporary nation state terms as southern Saskatchewan. This approach privileges thinking with objects in an effort to dislodge colonial assumptions about place and belonging, encouraging dialogic meaning-making about historical and contemporary life with Treaty in Western Canada.
Development of a Health-Related Quality of Life Measure for Peripheral Neuropathy
Authors: Vickrey Barbara G. , Hays Ron D. , Beckstrand Maggi
Published: November 2015

Statement of Problem:

To develop and evaluate a self-administered health-related quality of life (HRQOL) measure for peripheral neuropathy.

Methods:

A field test measure of 162 items was developed that included the RAND-36 Health Survey as a generic core and a neuropathy-targeted supplement whose content was driven by results from three focus groups with 22 adults having peripheral neuropathy. It was administered at baseline and at 3- and 6-month follow-ups to 80 adult clinical trial enrollees with diabetic neuropathy. Item reduction and placement into scales, reliability, construct validity, responsiveness, and HRQOL comparisons to a general U.S. population were conducted.

Results:

The final 97-item instrument includes 16 multi-item scales and 6 single items. Internal consistency reliabilities ranged from 0.67 to 0.93 (median = 0.88); intraclass correlation coefficients for those reporting no change in health between baseline and 3 months ranged from 0.42 to 0.84 (median = 0.77). Factor analysis of scales revealed physical and mental health as the two underlying dimensions. Correlations between selected HRQOL scales and sociodemographic variables were modest; there were more noteworthy associations between HRQOL scales and employment, disability days, and neurologic symptom ratings. Associations of HRQOL with neurologic examination (strength and reflexes) and with electrophysiologic findings were nonsignificant (all p > 0.10). Responsiveness of a physical health summary score relative to a criterion of change in subject's ratings of neuropathy symptom severity yielded a moderate effect size (= 0.60) and a Guyatt statistic exceeding 1.0.

Conclusions:

Results provide preliminary support for the measure's reliability and validity among adults with diabetic peripheral neuropathy. HRQOL was more strongly associated with symptom ratings than with examination and electrophysiologic test results.
Mirror Movements Complicate Interpretation of Cerebral Activation Changes during Recovery from Subcortical Infarction
Authors: Wittenberg George F. , Bastian Amy J. , Dromerick Alexander W. , Thach W. Thomas , Powers William J.
Published: November 2015

In recovered stroke patients, performance of motor tasks with the affected limb has been reported to activate cortical areas ipsilateral to the affected side. The better to determine the causal role these areas play in recovery of motor function, we assessed cerebral activation during motor activity longitudinally after hemiparesis due to cerebral infarction. A secondary goal was to ascertain the relation between mirror movements and activation ipsilateral to motor activity. Positron emission tomography with oxygen-15 water measured regional cerebral blood flow during wrist movement early and late in the course of recovery from hemiparesis. Surface electromyography recorded muscular activity, and computer-assisted video analysis quantified movement during the scans. Mirror movements, movements contralateral to the instructed movement of the hemiparetic arm, were often seen. Activation of motor areas in the hemisphere ipsilateral to the affected limb roughly correlated with presence of mirror movements. Other changes in cerebral activation were small, when the task was controlled for rate, but high-rate-specific recruitment of ipsilateral cortical areas occurred in one case. However, the common occurrence of mirror movements, particularly with effortful tasks, complicates interpretation of data regarding the role of the ipsilateral hemisphere in recovery.
The Processing of Stereoscopic Information in Human Visual Cortex: Psychophysical and Electrophysiological Evidence
Authors: Skrandies Wolfgang
Published: November 2015

Three-dimensional depth perception relies in part on the binocular fusion of horizontally disparate stimuli presented to the left and right eye. The mammalian visual system offers a unique possibility to study electrophysiologically cortical neuronal mechanisms: since the input of the two eyes remains separated up to the level of the visual cortex, evoked potential components that are generated exclusively by cortical structures may be explored when dynamic random-dot stereograms (dRDS) are presented.

In a series of independent studies, we determined the scalp topography of dRDS evoked brain activity in different groups of healthy subjects, and we found consistent results. Major differences between stereoscopic and contrast evoked brain activity are seen in the strength of the potential fields as well as in their topography. Our findings suggest that there are fewer neurons in the human visual cortex that are responsive to horizontal disparity, and that higher visual areas like V2 are more engaged with stereoscopic processing than the primary visual cortex. On the other hand, component latencies of evoked brain activity show no effect signifying that the binocular information flow to the visual cortex has a similar time course for both the processing of contrast information and of dRDS stimuli.

We could also verify that healthy subjects can learn to perceive 3D structure contained in dRDS. Changes in perceptual ability as measured with psychophysical tests are paralleled by systematic alterations in the topography of stereoscopically evoked potential fields. Stereoscopic VEP recordings may also be of clinical use: in patients with selectively disturbed depth perception but normal visual acuity there is a high correlation between clinical symptoms, perceptual deficiency, and altered VEP amplitudes and latencies.
Electrophysiology of the Frontal Lobe
Authors: Niedermeyer E.
Published: November 2015

The electrophysiology of the frontal lobe appears to be unimpressive when the view is limited to the routine EEG recording of a healthy waking adult. There is usually low voltage fast activity, which becomes more pronounced when recorded with depth leads.

Three special EEG patterns of marginal to slightly abnormal character are discussed: a) rhythmical midfrontal 6–7/sec activity of juveniles, b) rhythmical midfrontal sharp 4–6/sec activity of infancy and early childhood with arousal from sleep, and c) frontal intermittent rhythmical delta activity (FIRDA) in waking adults with frontopolar maximum, possibly related to thought processes under abnormal conditions.

With extension of the frequency range, ultraslow (DC-like) as well as fast beta (gamma, 40–80/sec) and ultrafast activity (80–1000/sec) are found particularly over the frontal lobes. Ultraslow baseline shifts are arousal-related and mixed with overlying ultrafast waves. Attention control and the “working memory” involve chiefly the dorsolateral prefrontal cortex, investigated with P300 responses and likely to show ultrafast spectra. Perception-related 40–80/sec gamma activity has been thought to be associated with the entrance into consciousness.

Initiation and design of motor activity spreads from prefrontal to the frontomotor cortex, associated with powerful event-related potentials: contingent negative variation (CNV) and “Bereitschafts potential” (“readiness potential,” RP).

Neuroscientific research of the highest frontal lobe functions has become a very active domain of neuroimaging. With the use of the extended frequency range, EEG and also evoked potential studies could add further information with acquisition in real time. Ultrafast frequency ranges presented in computerized frequency analysis and mapping might show impressive correlates of highest frontal lobe functions.
Spikes Immediately after Electroconvulsive Therapy in Psychotic Patients
Authors: Kubota Fumio , Shibata Nobuyoshi , Akata Takushiro , Kikuchi Senichiro , Kifune Akira , Yuuki Naoya , Takeuchi Kazuo
Published: November 2015

The goal of this study was to assess the spikes systematically and to clarify an epileptic abnormality induced by electroconvulsive therapy (ECT). Our subjects were 20 psychotic patients with no spikes on prior EEGs. ECT was performed by applying electrical current to both sides of the patient's temple every 2 or 3 days for a period of between 1–4 weeks. The first EEG examination was performed either on the day that the ECT course was completed or on the following day. Subsequent EEG examinations were performed at intervals of 2 or 3 days. Thirteen of the 20 patients showed spikes. There were no significant differences in age, gender, diagnosis, or type of ECT.

Patients with spikes had significantly more ECT sessions than those without spikes. The spikes were present in the frontal, temporal and central areas, predominantly frontal, anterior temporal and mid-temporal region, and almost disappeared in 1–3 weeks. The occurrence of spikes immediately after ECT was demonstrated. Although this abnormality was transient, it could indicate that in humans ECT causes the early stage of kindling phenomenon as a result of repeated application, and that the temporal lobe seems to play a major role in order to induce the phenomenon.
Acute Marihuana (THC) Exposure Produces a “Transient” Topographic Quantitative EEG Profile Identical to the “Persistent” Profile Seen in Chronic Heavy Users
Authors: Struve Frederick A. , Manno Barbara R. , Kemp Philip , Patrick Gloria , Manno Joseph E.
Published: November 2015

In two published pilot studies and a controlled replication using screened normals, chronic marihuana (THC) use was associated with a unique topographic quantitative EEG profile, consisting of significant elevations of Absolute and Relative Power and Coherence of alpha activity over the bilateral frontal cortex as well as a significant decrease in alpha frequency. This report attempts to establish the causal influence of THC in the above findings by the transient production of this exact quantitative EEG profile in subjects who did not display it at the beginning. Using paced smoking of marihuana with high and low dose THC content and placebo marihuana in a counterbalanced design under double blind conditions, all four of the topographic features of chronic THC exposure were produced as transient effects by THC but not by placebo.
Value of the Early Electroencephalogram after a First Unprovoked Seizure
Authors: Schreiner A. , Pohlmann-Eden B.
Published: November 2015

Studies on the predictive value of the electroencephalogram (EEG) concerning the risk of seizure recurrence have shown contradictory results. We prospectively studied the predictive value of the standard EEG and EEG with sleep deprivation for seizure relapse in adult patients presenting with a first unprovoked seizure.

EEGs were performed on 157 adult patients within the first 48 hours of the first seizure. Additional EEGs with sleep deprivation were obtained in 60 cases. The standard EEG was abnormal in 70.7% and significantly associated with an increased risk of seizure recurrence [risk ratio 4.5, 95% confidence interval (CI) 1.8; 11.3, p=0.001]. Subgroup analysis revealed the highest recurrence rates for patients with focal epileptiform activity (risk ratio 2.2, CI 1.2; 4.2, p=0.01). EEGs with sleep deprivation were abnormal in 48.3% of all cases and revealed epileptiform discharges in 13.3% of the patients who had no epileptiform activity in the standard EEG.

Routine EEG revealed abnormalities in 60 of 94 patients who presented with normal neurologic status on admission. Further neuroradiological examinations detected previously unknown brain lesions in 19 of these cases, particularly cerebrovascular disease (CVD, n=7), brain tumors (n=6), and posttraumatic scars (n=4).

In conclusion, the EEG is important for the early detection of focal nonepileptic and epileptic abnormalities after a first unprovoked seizure in adult patients and may provide valuable information on previously unknown disorders, particularly CVD and cerebral tumors. The abnormal EEG is a highly significant predictor for seizure recurrence. An additional EEG with sleep deprivation is helpful in cases when standard EEG does not reveal epileptiform discharges.
A Case of Mild Alzheimer's Disease Accompanied by Periodic Synchronous Discharges
Authors: Ishikawa Hiroyasu , Sekine Atsushi , Kanbayashi Takashi , Shimizu Tetsuo
Published: November 2015

Periodic synchronous discharges (PSD) on the electroencephalogram can be observed in diseases such as Creutzfeldt-Jakob disease, hypoxic encephalopathy and Alzheimer's disease (AD). However, in previously reported cases of AD with PSD, PSD have only been found many years after the diagnosis of AD. We recently encountered a patient with mild AD accompanied by transient PSD. To our knowledge, this is the first case report to suggest that PSD can occur in mild AD.
Event-Related Potentials in Young and Elderly Adults during a Visual Spatial Working Memory Task
Authors: Knott Verner , Millar Anne , Dulude Louise , Bradford Lisa , Alwahhabi Fahad , Lau Tim , Shea Catherine , Wiens Andrew
Published: November 2015

The P300 event-related brain potential (ERP) was examined in 14 young (20–29 years of age) and 16 elderly (60–82 years of age) subjects during the performance of a visuospatial memory task requiring recognition of locations. Elderly and young adults exhibited similar recognition accuracy, but recognition reaction times were significantly slower in the elderly. Midline P300 amplitudes recorded in response to visuospatial probe stimuli were significantly attenuated in the elderly, and, depending on the nature of the probe, P300 latency-derived indices indicated that both cognitive and motoric slowness characterized visuospatial recognition in the aged. The results, discussed in relation to neural mechanisms supporting working memory function, suggest that alterations in attention and processing speed may play a role in visual-spatial working memory deficits associated with normal and pathological aging.
Auditory Evoked Responses in a Comparison between Schizophrenia Patients with and without Premorbid History of Drug Abuse: Report of Pilot Results
Authors: Boutros Nash N. , Korzyukov Oleg , Oliwa Glen , Struve Frederick , Jansen Ben H.
Published: November 2015

Evidence for a role for drugs of abuse in the development of chronic psychotic syndromes is scattered throughout 40 years of literature. Electrophysiological studies examining groups believed to have chronic drug-induced psychotic symptoms yielded interesting findings. To our knowledge, no studies directly compared schizophrenia patients whose drug use preceded and those whose drug use followed the onset of psychotic symptoms.

Twenty-six schizophrenia patients and 10 healthy control subjects were recruited for the study. Based on the SCID interview, schizophrenia subjects were classified into a Psychosis First (Psy 1st) group (N=11), Drugs First (Drugs 1st; N=8), and No Drug Use (No Drugs; N=7). Schizophrenia subjects were administered the Positive and Negative Symptoms Scale (PANSS). The P300 evoked response and sensory gating were measured for all subjects. Despite the small sample sizes significant differences were found between the groups. Most significantly, the P300 amplitude was smallest in the Drugs 1st as compared to the No Drugs groups, while sensory gating deficit was worst in the Psy 1st group. The data suggest that significant clinical and electrophysiological differences between these groups can be identified. Further research to better define these differences seems warranted.
High-Frequency Oscillations in Somatosensory System
Authors: Mochizuki Hitoshi , Ugawa Yoshikazu
Published: November 2015

The recent revival of interest in high-frequency oscillation (HFO) is triggered by getting an opportunity to noninvasively monitor the timing of highly synchronized and rapidly repeating population spikes generated in the human somatosensory system. HFOs could be recorded from brainstem, cuneothalamic relay neurons, thalamus, thalamocortical radiation, thalamocortical terminals and cortex with deep brain or surface electrodes, or with magnetoencephalography. Here we briefly review the HFOs at each level of somatosensory pathways. HFOs recorded at brainstem might be produced by volume conduction from oscillations of the medial lemniscus. Thalamic HFOs at around 1000 Hz frequency would be generated within the somatosensory thalamus. Cortical HFOs would be generated by at least a few different mechanisms, thalamocortical projection terminals, interneurons and pyramidal cells of the primary sensory cortex. HFOs have been studied in several ways: their modulation by arousal changes, movements or drugs, their recovery function, effects of transcranial magnetic stimulation on them and also their changes in patients with various neurological diseases.
500–1000 Hz Responses in the Somatosensory System: Approaching Generators and Function
Authors: Klostermann Fabian
Published: November 2015

Spontaneous and stimulus-induced oscillatory EEG activities range over a wide scope of frequencies from 1 Hz to 1 kHz. In the ultrafast domain, trains of 5–10 micro-potentials are superimposed to primary thalamic and cortical components in somtosensory evoked potentials (SEP) as brief bursts of 1000 Hz and 600 Hz, respectively. Over the last years, hypotheses on generators and functions of this frequency-edge of population activity have been elaborated in numerous studies. Here, the relevant findings and ideas were surveyed from the body of literature. Special emphasis was paid to the anatomical and cellular origin of burst SEP, their assumed impact on somatosensory coding and perspectives for scientific as well as clinical applications.
Feasibility of an Intraluminal Bypass Device in Low Colorectal Anastomosis
Authors: Willenz Udi , Wasserberg Nir , Botero-Anug Ana Maria , Greenberg Ron
Published: November 2015

Background: The Cologuard CG-100 is a novel intraluminal bypass device designed to reduce the clinical outcomes associated with low colorectal anastomotic leak. The device is inserted transanally, anchored to the colon above the anastomosis, and deployed intraluminally to cover the anastomosis from within. The purpose of this study was to evaluate the safety and performance of the device in a porcine model. Method: Twelve pigs underwent low colorectal anastomosis with insertion of the Cologuard CG-100 device. Contrast material injection, abdominal X-ray, and histologic studies were used to evaluate sealing quality, device positioning, and tissue damage, respectively. The surgeons completed a usability and satisfaction questionnaire after completion of the procedure. Results: Absolute sealing was observed in all 4 animals euthanized immediately after surgery. In the other 8 animals, the device was kept in situ for 10 days and then extracted. X-ray films with injection of contrast material through a designated injection tube before device removal showed that the sheath and ring were correctly placed. No leak was demonstrated. There were no device-related adverse events, and no critical histological abnormalities were noted in the bowel area that was compressed by the device. The device was found to be easy to insert, position, and extract. Conclusion: The Cologuard CG-100 device efficiently reduced contact between fecal content and low colorectal anastomosis in a porcine model and is easily deployed and extracted. It holds promise for possible clinical use pending further studies.
Improving Surgical Resection of Metastatic Liver Tumors With Near-Infrared Optical-Guided Fluorescence Imaging
Authors: Barabino Gabriele , Porcheron Jack , Cottier Michèle , Cuilleron Muriel , Coutard Jean-Guillaume , Berger Michel , Molliex Serge , Beauchesne Brigitte , Phelip Jean Marc , Grichine Alexei , Coll Jean-Luc
Published: November 2015

Objective. The aim of this study was to investigate the feasibility and future clinical applications of near-infrared (NIR) fluorescence imaging to guide liver resection surgery for metastatic cancer to improve resection margins. Summary Background Data. A subset of patients with metastatic hepatic tumors can be cured by surgery. The degree of long-term and disease-free survival is related to the quality of surgery, with the best resection defined as “R0” (complete removal of all tumor cells, as evidenced by microscopic examination of the margins). Although intraoperative ultrasonography can evaluate the surgical margins, surgeons need a new tool to perfect the surgical outcome. Methods. A preliminary study was performed on 3 patients. We used NIR imaging postoperatively “ex vivo” on the resected liver tissue. The liver tumors were preoperatively labelled by intravenously injecting the patient with indocyanine green (ICG), a NIR fluorescent agent (24 hours before surgery, 0.25 mg/kg). Fluorescent images were obtained using a miniaturized fluorescence imaging system (FluoStic, Fluoptics, Grenoble, France). Results. After liver resection, the surgical specimens from each patient were sliced into 10-mm sections in the operating room and analyzed with the FluoStic. All metastatic tumors presented rim-type fluorescence. Two specimens had incomplete rim fluorescence. The pathologist confirmed the presence of R1 margins (microscopic residual resection), even though the ultrasonographic analysis indicated that the result was R0. Conclusions. Surgical liver resection guided by NIR fluorescence can help detect potentially uncertain anatomical areas that may be missed by preoperative imaging and by ultrasonography during surgery. These preliminary results will need to be confirmed in a larger prospective patient series.