cssi/SciSciGPT-SciSciNet huggingface dataset:
Robust current mode control of switching DC-DC converters

Summary form only given. The authors propose an approach that results in a controller and filter design that is optimal and robust and in which the interacting effects (coupling) of the filter and the controller are used as extra degrees of freedom in the selection of the controller gains and filter components. In particular, the controller and filter design methodology is based on a linear quadratic formulation that accounts for the different constraints on design specifications. The resulting controller structure has the following components: (1) feedforward gains that provide anticipative response control to all nonexciting and limited-time-exciting commands and disturbances in the input voltage and that also alter the zeros of the resulting closed-loop system; (2) a servocompensator positioned in the forward loop path of the converter model to ensure asymptotic tracking of the commanded voltage and rejection of all disturbances; (3) state feedback and a filter to enforce the desired high gain at low frequency and low gain at high frequency and approximately -20-dB/s/dec slope at the crossover frequency in order to attain satisfactory phase margin. A proportional integral (PI) observer, instead of using a hardware current sensor, is used to estimate the inductor current. The controller and filter of a 50-W, DC-DC buck converter that supplies a load with a constant output voltage of 5 V have been designed and implemented in hardware. >
Eldoret: An African Poetics of Technology

Eldoret: An African Poetics of Technology. Richard M. Swiderski. Tucson: University of Arizona Press, 1995. 228 pp.
Air Distribution Over a Combustor Liner

The splitting of the airflow that passes through the openings in the combustor liner is vital to its performance. Traditionally, numerical simulations of the gas turbine combustor have limited the computational domain to only the flow field inside the liner, while the airflow distribution over the liner is estimated based on semi-empirical correlations. In addition, the airflow rates are assumed to be the same through the identical open passages at each combustor axial cross-section. In the present study, the internal and external flow fields of a practical gas turbine combustor liner are directly coupled, so the air splitting is determined by comprehensive simulations. The predicted results for the air distribution are closely correlated to the dataset estimated from recently improved semi-empirical correlations for passage discharge-coefficients. The simulations also show that the effects of the combustion process on the air splitting can be neglected. Lastly, the results reveal that the airflow through identical passages at the same axial cross-section are not equal, and can vary by up to ±25% of the mean. In summary, the present study suggests that when performing computational models of gas turbine combustor flows, the simulations should couple the liner’s internal and external air splits whenever possible.Copyright © 2014 by Her Majesty the Queen in right of Canada
Spontaneous emission faster than stimulated emission

With an optical antenna, spontaneous emission can be stronger and faster than stimulated emission, allowing direct modulation LED's for optical interconnects. We will present the evidence for 35X spontaneous emission enhancement by an optical antenna.
Permeant anions are not required for norepinephrine secretion from pheochromocytoma cells.

Abstract The ‘chemiosmotic’ model for secretion proposed by Pollard and his colleagues (Int. Rev. Cytol. 58, 159–197, 1979) was tested with pheochromocytoma cells. Contrary to the prediction of this model, norepinephrine secretion did not require the presence of a permeant anion in the medium. Secretion was not blocked by replacing much of the Cl − of the medium with isethionate or by replacing all of the Cl − salts of the medium with isotonic sucrose. Biochemical evidence is presented to indicate that the cells secreted by the normal exocytotic mechanism in the sucrose medium. Making the normal bathing medium hypertonic with 300 mM sucrose increased the basal level of norepinephrine release, but alos suppressed secretion in response to a strong secretagogue (1 mM Ba 2+ ). The data indicate that the Pollard model does not apply to pheochromocytoma cells, but suggest the possible involvement of osmotic pressure in exocytosis.
Numerical Simulation of Deep-Well Injection in Geismar, Louisiana

Industrial waste water has been injected into a permeable part of the Upper Miocene injection reservoirs near Geismar, Louisiana since 1971. The injection zone is a series of alternating extremely permeable sands and impermeable clays, hydraulically isolated from the surficial aquifer system by a thick layer of clay, which acts as a confining layer. The study area encompasses four industrial facilities and 12 active injection wells. Numerical simulations were performed to evaluate injection-well design and potential for movement of injected waste water within the hydrogeologic system. Numerical modeling was conducted in both cylindrical coordinates and Cartesian coordinates. A convection cell developed around a single prototype injection well in cylindrical-coordinate system with a buoyant injection rising to form a lens within the injection zone. Around an ideal, fully penetrating well cased into the injection sand and open from a depth of 5,056 feet to 5,456 feet, simulations show the injectant moves upward to a depth of 4,866 feet, forms a lens about 400 feet thick, and spreads radially outward to a distance of 1,670 feet after 10 years. Comparison simulations of injection through wells having open depth intervals of 5,056 to 5,256 feet and 5,256 to 5,456 feet demonstrate that such changes in well design have little effect on the areal spread of the injectant lens or the rate of upward movement. Multiple injection well simulations in Cartesian coordinates indicate that about 5,10, and 80 percent of the study area would be underlain by injected waste water after 10,20, and 100 years of injection, respectively. Outward movement of waste water proceeds even after injection stops. The rate of outward movement under the post-operational period (after injection ceases) is much smaller than under the operational period (injection period).
Familial Episodic Ataxias and Related Ion Channel Disorders.

Familial episodic ataxias are unusual hereditary disorders of early onset characterized by recurrent episodes of ataxia. Most patients recover fully between attacks, but some may develop progressive ataxia with cerebellar atrophy. There are two subtypes of episodic ataxia: type 1 (EA1), with interictal myokymia, and type 2 (EA2), with interictal nystagmus. Stress and fatigue can trigger ataxic spells, which can be responsive to acetazolamide [1••, Class III]. These clinical features are reminiscent of other channelopathies or paroxysmal neurologic disorders with progressive features caused by ion channel mutations [2]. Familial episodic ataxias indeed are channelopathies. EA1 is caused by mutations in a potassium channel-encoding gene, whereas EA2 is caused by mutations in a calcium channel-encoding gene, which is also the disease-causing gene in spinocerebellar ataxia type 6 and several kindreds with familial hemiplegic migraine. Treatment with acetazolamide can be effective in decreasing the frequency of attacks and is generally well tolerated. Understanding the mechanism of action of acetazolamide and the functional consequences of these mutations will help one to develop a rational pharmacologic treatment for these disorders, which may share similar mechanisms with benign recurrent vertigo and more common forms of migraine.
Analysis and synthesis of resistive n-port networks☆

Abstract Various aspects of analysis and synthesis of resistive n-port networks are considered in this paper. Two different characterizations of the network are examined, the Y matrix characterization and the K matrix characterization. Based on these characterizations, a set of equations is derived which relate the edge admittances with the elements of these matrices. When the K matrix is given, these equations are linear and can be solved analytically. When the Y matrix is given, the equations are bilinear and cannot be solved analytically. In this case, the problem is formulated as an optimization problem and techniques of nonlinear programming are used to obtain a realization. Synthesis from the Y matrix is finally extended to include sensitivity considerations.
Behavioral and Recreational Risk Factors for Free‐Living Amebic Infections

Free‐living amebae of the genera Acanthamoeba , Balamuthia , Naegleria , and Sappinia are rare causes of infectious diseases in humans with the exception of Acanthamoeba keratitis (AK), which is reported in over 10,000 soft contact lens wearers annually worldwide. Unlike several Acanthamoeba species, which can cause both AK and granulomatous amebic encephalitis (GAE), only one species of Naegleria , Naegleria fowleri , is known to infect humans by causing an acute, fulminant, usually lethal, central nervous system (CNS) infection, known as primary amebic meningoencephalitis (PAM). 1–6 Both Acanthamoeba species and N fowleri are distributed worldwide; found commonly in freshwater; and have even been isolated from tap water, air conditioning systems, and improperly maintained swimming pools. 1–5 Balamuthia mandrillaris , formerly known as leptomyxid ameba, is another opportunistic, free‐living ameba. Like Acanthamoeba spp, B mandrillaris is capable of causing skin lesions and GAE in individuals with compromised or competent immune systems, who inhale infective spores or develop indolent, granulomatous skin lesions in soil‐contaminated wounds. Lastly, Sappinia pedata , a recently identified free‐living ameba that lives in soil and domestic animal feces, has caused a single case of non‐GAE in an immunocompetent Texas farmer. CNS infections caused by these ubiquitous organisms remain rare despite expanding world populations; but are, nevertheless, increasing today due to a combination of factors including increased freshwater recreational activities during heat waves for PAM, more immunocompromised individuals susceptible to GAE, and more soft contact lens wearers at risk of AK. 6,7 The purpose of this review will be to describe the epidemiology, pathophysiology, clinical manifestations, diagnosis, and management of free‐living amebic infections. In addition, United States Centers for Disease Control and Prevention (CDC) laboratory‐confirmed cases of PAM, B mandrillaris GAE, and AK will be analyzed statistically to determine significant risk factors for exposure and infection; and to … Corresponding Author: James H. Diaz, MD, MPH&TM, Dr PH, School of Public Health, Louisiana State University Health Sciences Center (LSUHSC) in New Orleans, 1615 Poydras Street, Suite 1400, New Orleans, LA 70112, USA. E‐mail: jdiaz{at}lsuhsc.edu
Criteria for evaluating the reliability of literature data on environmental process constants

In the assessment of health risk from pollutant exposure, it is important for the modeler to know the degree of confidence he/she can have in literature values that are needed for estimating the fate of toxic substances in the environment. Since literature values, in general, are of unknown reliability, evaluation criteria were developed for twelve rate and equilibrium constants used in environmental modeling. The evaluation criteria also can be used to assess the reliability of literature values for other properties.
PERFLUOROCHEMICAL (PFC) BLOOD UPTAKE DURING PARTIAL LIQUID VENTILATION: EFFECT OF LUNG CONDITION. † 1998

PERFLUOROCHEMICAL (PFC) BLOOD UPTAKE DURING PARTIAL LIQUID VENTILATION: EFFECT OF LUNG CONDITION. † 1998
New perspectives on hereditary influences in metastatic progression

Metastasis, the process by which cancer cells spread to distant sites and form secondary tumors, depends upon the ability of cells to escape the primary tumor, and colonize and proliferate in a novel microenvironment. Many mechanisms have been proposed to explain this phenomenon although no theory has comprehensively explained all biological observations. There is growing evidence that host hereditary factors modulate the ability of tumor cells to form metastatic lesions, and host genetic polymorphism could be a significant variable in this process. This review is intended to illustrate the role of hereditary variation in metastatic progression, how this integrates with currently proposed metastatic mechanisms, and the potential clinical impact on this frequently fatal consequence of cancer.
AMPA, kainic acid, and N-methyl-D-aspartic acid stimulate locomotor activity after injection into the substantia innominata/lateral preoptic area

The substantia innominata/lateral preoptic area (SI/LPO) is a subpallidal region which has been shown to regulate the hypermotility produced by drugs acting in the nucleus accumbens. Evidence has been presented that the SI/LPO contains glutamatergic nerve terminals and receptors for excitatory amino acids. The purpose of this study was to determine the effects of the activation of excitatory amino acid receptors in the SI/LPO on locomotor activity following the direct injection of excitatory amino acids into this brain site. It was found that the bilateral injection of alpha-amino-3-hydroxy-5-methyl-isoxazole-4-propionate (AMPA), kainic acid, and N-methyl-D-aspartic acid into the SI/LPO produced marked dose-dependent stimulations of locomotor activity which resembled the effects of these agents after their injection into the nucleus accumbens. The effect, however, was bell-shaped in that at high doses, the locomotor activity values decreased from their peak values. The coinjection of gamma-glutamylaminomethylsulfonate (GAMS) with AMPA into the SI/LPO was found to inhibit the hypermotility response to AMPA at doses that were unable to produce a significant inhibition of the hypermotility responses to kainic acid or N-methyl-D-aspartic acid. The injection of 6,7-dinitroquinoxaline-2,3-dione (DNQX) into the SI/LPO inhibited the hypermotility responses to AMPA or kainic acid while having no significant inhibitory effect on N-methyl-D-aspartic acid stimulated locomotor activity. The injection of D-alpha-aminoadipic acid into the SI/LPO produced a significant inhibition of the hypermotility response produced by N-methyl-D-aspartic acid at a dose that did not produce a significant inhibition of the hypermotility response produced by AMPA.(ABSTRACT TRUNCATED AT 250 WORDS)
Information loss in three cell-level control techniques for summary tables

Abstract A statistical database (SDB) is a database that provides simple summary statistics (e.g., SUM, COUNT, MAX, MEDIAN, etc.) about individuals in the database and that supports statistical data analysis. When SDB users infer protected information in the SDB from responses to queries, we say that the SDB is compromised. Summary tables are tabular representations of summary data. For a given aggregate function and a set of attributes to specify subsets of individuals in the SDB, all possible summary tables form a lattice. The SDB security problem in the lattice model is defined as preventing the users from obtaining the information that a table element (i.e., cell) is of size one. In this paper, to solve the SDB security problem in the lattice model, we generalize three cell-level control techniques, namely, cell suppression by merging, m -cube, axis merging, into the lattice model. We define the concept of information loss, derive various properties of the minimum information loss, and then investigate the effectiveness of heuristic algorithms for the minimum information loss in each of the three cell-level control techniques.
Numerical evaluation of wind-induced dispersion of pollutants around a building

Abstract Wind flow perturbations, recirculations and turbulence generated by buildings often dominate air pollutant distributions around buildings; this may be a great concern for engineers, architects and health professionals. The paper refers to an attempt to evaluate the air pollutant distribution around a building by solving the concentration equation based on the previously simulated wind flow field. The paper shows the application of the hybrid scheme for the evaluation of pollutant concentration around a rectangular building for two different sources under conditions of neutral atmospheric stratification. Results have been compared to the available experimental data from previous studies in boundary layer wind tunnels. Data agree well far downwind of the building but agree less satisfactorily close to the wall and within the wake zone.
Promoting Excellence in Nursing Education (PENE): Pross evaluation model

The purpose of this article is to examine the Promoting Excellence in Nursing Education (PENE) Pross evaluation model. A conceptual evaluation model, such as the one described here, may be useful to nurse academicians in the ongoing evaluation of educational programs, especially those with goals of excellence. Frameworks for evaluating nursing programs are necessary because they offer a way to systematically assess the educational effectiveness of complex nursing programs. This article describes the conceptual framework and its tenets of excellence.
Reconfigurable arrays of collocated sensors and actuators for modal isolation

Arrays of sensors and actuators designed to provide robust broadband feedback control with high performance and limited modeling are the subject of this paper. The reconfigurable array technique proposed here enables the design of reduced- order controllers for complex structures and offers the potential to improve closed-loop robustness and to broaden the region of good performance even as the plant changes. The weighted summation of sensor signals senses the modes that are relevant to performance while rejecting the remaining modes; therefore reducing the required complexity of the controller. These weights are obtained from the minimization of a cost function and under certain assumptions; it can be shown that a single optimum solution exists. The use of reconfigurable arrays is motivated by the need to control the vibration of complex structures. A thirty element collocated actuator and sensor array was bonded to a cylinder section. Array weights were computed and successfully applied to isolate target modes. Different methods of computing the weights are implemented and compared. The deleterious effects of spatial aliasing and the performance as a function of the array size are experimentally explored.
Effects of synthetic antioxidants (BHA, BHT and PG) on the mutagenicity of IQ-like compounds☆

Abstract This study investigated the effects of the phenolic antioxidants (BHA, BHT and PG) on the mutagenicity of IQ, MeIQ and MeIQx by the Ames test. Results demonstrated that MeIQ, IQ and MeIQx were all mutagenic when tested with the Ames test with their potency being in the order listed above. This was true on testing with both TA98 and TA100, both of which required added S-9 for activation. It was clearly demonstrated that BHA and PG significantly inhibited the mutagenicity of IQ, MeIQ and MeIQx. On the other hand, BHT had little effect on the mutagenicity of IQ and MeIQ at low concentrations, but significantly increased their mutagenicity at high concentrations. BHT slightly inhibited the mutagenicity of MeIQx at all concentrations tested.
Altitude Effects Of The Atmospheric Modulation Transfer Function

Measurements of the atmospheric modulation transfer function (MTF) along a vertical path are presented for both mountain and desert locations. The mountain and desert sites are found to be equivalent during the day but, at night, the mountain sites have twice the resolution observed at desert locations. The atmospheric MTF above the desert at night is found to be essentially the same as during the day. Measurements of the optical turbulence in the first kilometer above the surface are shown to account for these findings.© (1980) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.
Commercial Driver Factors in Run-off-Road Crashes

The number of commercial vehicles on U.S. roads has grown dramatically over the past few decades. Although the number of large trucks involved in fatal and injury crashes has decreased over the past 20 years, large trucks still have a higher fatal crash involvement rate than passenger cars do. This study sought to gain insights on the impact of commercial driver factors on crash severity with respect to single-vehicle, run-off-road (ROR) crashes. A logistic model was conducted with large truck crash data from the Washington State Department of Transportation (years 2006 to 2009). The model predicted the effects of truck driver distraction, inattention, speeding, seat belt usage, and drowsiness and fatigue on the likelihood of an ROR crash involving injury or fatality. Other factors, such as environmental conditions, roadway types, and truck-related factors, were controlled in the model. Results indicated that speeding, drowsiness and fatigue, and distraction and inattention strongly affected increasing cr...
African American College Women's Body Image: An Examination of Body Mass, African Self-Consciousness, and Skin Color Satisfaction.

The purpose of this study was to examine general and cultural factors associated with body image perceptions of African American women college students. A total of 124 African American college women attending a historically Black college completed the following scales: African Self-Consciousness (ASC) scale, the Skin Color Satisfaction Scale (SCSS), the Body Mass Index (BMI), and several body image measures. Results from simultaneous multiple regression analyses suggest that all three factors collectively accounted for a significant amount of variance in dimensions of body image satisfaction. Specifically, SCSS accounted for a significant amount of variance in three body image dimensions (i.e., appearance evaluation, satisfaction with specific body areas, internalization of social cultural messages of appearance), suggesting that the greater satisfaction with one's skin color was associated with more positive, internal perspectives of one's body image. The BMI accounted for a significant amount of varianc...
Polynomial-time algorithms for generation of prime implicants

Abstract A notion of a neighborhood cube of a term of a Boolean function represented in the canonical disjunctive normal form is introduced. A relation between neighborhood cubes and prime implicants of a Boolean function is established. Various aspects of the problem of prime implicants generation are identified and neighborhood cube-based algorithms for their solution are developed. The correctness of algorithms is proven and their time complexity is analyzed. It is shown that all presented algorithms are polynomial in the number of minterms occurring in the canonical disjunctive normal form representation of a Boolean function. A summary of the known approaches to the solution of the problem of the generation of prime implicants is also included.
Graphene nano-ink biosensor arrays on a microfluidic paper for multiplexed detection of metabolites

Abstract The development of a miniaturized and low-cost platform for the highly sensitive, selective and rapid detection of multiplexed metabolites is of great interest for healthcare, pharmaceuticals, food science, and environmental monitoring. Graphene is a delicate single-layer, two-dimensional network of carbon atoms with extraordinary electrical sensing capability. Microfluidic paper with printing technique is a low cost matrix. Here, we demonstrated the development of graphene-ink based biosensor arrays on a microfluidic paper for the multiplexed detection of different metabolites, such as glucose, lactate, xanthine and cholesterol. Our results show that the graphene biosensor arrays can detect multiple metabolites on a microfluidic paper sensitively, rapidly and simultaneously. The device exhibits a fast measuring time of less than 2 min, a low detection limit of 0.3 μM, and a dynamic detection range of 0.3–15 μM. The process is simple and inexpensive to operate and requires a low consumption of sample volume. We anticipate that these results could open exciting opportunities for a variety of applications.
The Content of Cosmetic Surgery Advertisements Placed in Large City Magazines, 1985–2004

Abstract Cosmetic surgery advertisements largely were banned from the mass media until the 1982 Bates Supreme Court decision. Today, advertising is one of the major marketing drivers of cosmetic surgery procedures. Yet, little is known about the content properties of cosmetic surgery advertising, a sometimes controversial and increasingly competitive field. This study examines 1,857 cosmetic surgery advertisements in large city magazines over two decades, 1985–2004. Among other things, the results indicate that most advertisements used rational vs. emotional appeals and that physician credentials increased in importance. Risk information was virtually non-existent and some content may be at odds with medical codes of ethics.
Common mode noise characteristics of resonant converters

This paper investigates the common mode (CM) noise characteristics of resonant converters. Noise sources of CM EMI in isolated resonant converters were identified and analyzed. The operating point of the resonant converter has significant impact on CM noise of the converter. Utilizing the leakage inductance in the power transformer as the resonant inductor can reduce the high-frequency CM noise of some types of resonant converters. However, utilizing leakage inductance may limit the low-frequency reduction while adopting the CM noise reduction techniques.
Heavy Metal Leaching from Mine Tailings as Affected by Plants

A column experiment was conducted to determine the impact of soil cover and plants on heavy metal leaching from mine tailings and heavy metal contaminated soil. Columns made of PVC were constructed with 30 cm subsoil covered by 30 cm of mine tailings followed by 0, 30, or 60 cm subsoil covered by 30 cm of mine tailings followed by 0, 30, or 60 cm of clean topsoil. Two grasses, tall fescue (Festuca arundinacea Schreb.) and big bluestem (Andropogon gerardii), were grown in the columns. The columns were leached at a slow rate for 1 yr with a 0.001 M CaCl{sub 2} solution under unsaturated conditions. The presence of both tall fescue and big bluestem increased Zn and Cd concentrations in the leachate. Lead concentrations in leachates were not affected by the presence of plants. Although plants generally reduced the total amount of water leached, total mass of Zn and Cd leached generally was not impacted by plants. Total mass of Pb leached was positively correlated with total leachate collected from each column. Covering the mine tailings with 60 cm of topsoil increased the mass of Zn and Cd leached relative to no topsoil. When the subsoil was absent, Znmore » and Cd leaching increased by as much as 20-fold, verifying the ability of soil to act as a sink for metals. Mine tailing remediation by establishing vegetation can reduce Pb movement but may enhance short-term Cd and Zn leaching. However, the changes were relatively small and do not outweigh the benefits of using vegetation in mine tailings reclamation.« less
Psychotherapy with the elderly in public mental health settings

As public psychiatry programs for the elderly begin to emerge, we must refine our therapeutic theories and techniques in order to serve this population better.
Metallurgical study and tribological properties of edge card connector spring/tab interface

Summary form only given, as follows. The influence of composite metallurgical structure on the tribological behavior of an edge-card connector was studied. The study centered on the metallurgy of the card tab, which is a multilayer structure consisting of a printed circuit board with an overplated copper layer, nickel, hard gold, and soft gold. These experiments were performed under both dry friction and thin-film polyolester lubricated conditions. The thickness of each was found to alter the frictional characteristics of the surface. The experimental data were found to agree with Finkin's theoretical model for solid-film lubrication. The role of the soft-gold layer was identified as a friction/wear riser, rather than a solid lubricant. It was found that the addition of a minimum layer of lubricant can provide lower friction on contact surface and eliminate fretting wear. The lubricant also made the behavior less sensitive to the metallurgy. When the amount of lubricant was increased the coefficient of friction stayed almost the same from thin-film to flooded conditions. The difference in wear between the dry and thin film lubrication conditions was minor. >
FRONTLINE--a new paradigm for the third psychoanalytic revolution.

About a century ago, Freud, using his mind to study the mind of himself and others, first developed a systematic understanding of the unconscious, and linked his work to the methodology of science that permeated his intellectual environment. Unable to connect these mental processes to the organic substrate that sustained them, he resolved to “remain on psychological ground.” To solve his dilemma, he made the metapsychological assumption splitting mind and brain. This inspired decision represented a singularity in cultural evolution of near-miraculous proportions, and the first psychoanalytic revolution had begun. Freud’s studies transformed his age. His discoveries were progressively employed in the effort to assist disordered minds, and soon transformed psychiatry, education, the humanities, the arts, and the role of women during the following decades. Freud’s death was immediately followed by World War II, and both events seem to have potentiated the emergence of a second post–Freudian psychoanalytic revolution. The essence of Freud’s thought had found acceptance, but the euphoric idealization of science and power led the American Psychoanalytic Association to attempt control of the new adaptational acquisition. Bowlby’s nonmetapsychological and evolutionary studies were virtually suppressed, despite early signs that the emerging classical model was deficient. A reactionary period of consolidation, canonization, hypertrophy, and partition followed, and elements of the field later drifted toward nilihistic postmodernism. In contrast, during the early stages of this second revolution, the founders of the American Academy of Psychoanalysis in 1956 launched their organization. It emphasized their interest in social reality, femininity, and aversion to dogma. These efforts sought to return balance to a movement that now excessively stressed masculinized self–assertion (phallic narcissism). Importantly, during this period, many psychiatrists learned to use newly developed medications, as well as therapeutic empathy.
Typical cerebral hemisphere disconnection deficits following corpus callosum section despite sparing of the anterior commissure

Abstract Cerebral corpus callosum section is possibly as therapeutically effective as multiple cerebral commissurotomy while, according to the report of Risse et al. (Neuropsychologia 16, 23–31, 1978), allowing a substantially greater retention of the important adaptive function of inter-hemispheric exchange of information. We report results of visual, auditory and tactile tasks administered to three callosotomy patients. Results show typical “split-brain” deficits, in each modality. These results suggest that the anterior commissure is not an affective commissure in the transfer of stimulation effects over the follow-up period studied.
Is the metabolic response to sepsis in skeletal muscle different in infants and adults? An experimental study in rats.

Abstract In this study we compared the effect of sepsis on muscle protein metabolism in infant (3 to 4 weeks) and adult (3 to 4 months) rats. Sepsis was induced by cecal ligation and puncture (CLP). Control animals underwent sham operation. Sixteen hours after CLP or sham operation, metabolic studies were performed in incubated intact extensor digitorum longus muscles from infant rats or in strips of the same muscle from adult rats. Protein synthesis rate was determined as incorporation of 3 H-phenylalanine into protein; total and myofibrillar protein breakdown rates were determined as release of tyrosine and 3-methylhistidine, respectively. Mortality rate following CLP was similar in both age groups. Basal protein synthesis rate was 3 times higher, total protein breakdown rate was 50% higher, and myofibrillar protein breakdown rate was 3 times higher in infant than in adult animals. However, the relative changes in protein turnover rates induced by sepsis were similar in infant and adult rats: protein synthesis rate decreased by approximately 30%, total protein breakdown increased by 40% to 50%, and myofibrillar protein breakdown increased several-fold. The data suggest that despite prominent differences in basal protein turnover rates between infant and adult rats, the effect of sepsis on muscle protein metabolism is not age dependent.
Training slot allocation for mitigating estimation error propagation in a two-hop relaying system

This paper analyzes a channel estimation error propagation problem for a two-hop amplify-and-forward (AF) relaying system using two-phase. Channel estimator in each phase is obtained by the linear minimum mean squared error (LMMSE) method. The inaccuracy of estimation of the relay-to-destination (RtD) channel in the first phase affects the estimation of the source-to-relay (StR) channel in the second phase, making it more erroneous than the first phase. We derive an close-form expression for the averaged Bayesian mean-square estimation error (ABMSE) of both phases in terms of the length of source and relay training slots, based on which an iterative searching algorithm is then proposed which optimally allocates the training slots to each phase such that the estimation errors are balanced for both phases. Analysis shows how the ABMSE of StD channel estimation varies with the length of relay training slots, the length of source training slots, the relay amplification gain, and the channel prior information respectively. This scheme is shown to be substantially better than a random allocation scheme.
Acoustic trauma-induced auditory cortex enhancement and tinnitus

Abstract There is growing evidence suggests that noise-induced cochlear damage may lead to hyperexcitability in the central auditory system (CAS) which may give rise to tinnitus. However, the correlation between the onset of the neurophysiological changes in the CAS and the onset of tinnitus has not been well studied. To investigate this relationship, chronic electrodes were implanted into the auditory cortex (AC) and sound evoked activities were measured from awake rats before and after noise exposure. The auditory brainstem response (ABR) was used to assess the degree of noise-induced hearing loss. Tinnitus was evaluated by measuring gap-induced prepulse inhibition (gap-PPI). Rats were exposed monaurally to a high-intensity narrowband noise centered at 12 kHz at a level of 120 dB SPL for 1 h. After the noise exposure, all the rats developed either permanent (>2 weeks) or temporary (
Comparisons of forager distributions from matched honey bee colonies in suburban environments

We conducted experiments designed to examine the distribution of foraging honey bees (Apis mellifera) in suburban environments with rich floras and to compare spatial patterns of foraging sites used by colonies located in the same environment. The patterns we observed in resource visitation suggest a reduced role of the recruitment system as part of the overall colony foraging strategy in habitats with abundant, small patches of flowers. We simultaneously sampled recruitment dances of bees inside observation hives in two colonies over 4 days in Miami, Florida (1989) and from two other colonies over five days in Riverside, California (1991). Information encoded in the dance was used to determine the distance and direction that bees flew from the hive for pollen and nectar and to construct foraging maps for each colony. The foraging maps showed that bees from the two colonies in each location usually foraged at different sites, but occasionally they visited the same patches of flowers. Each colony shifted foraging effort among sites on different days. In both locations, the mean flight distances differed between colonies and among days within colonies. The flight distances observed in our study are generally shorter than those reported in a similar study conducted in a temperate deciduous forest where resources were less dense and floral patches were smaller.
Flow Through a Micro-Bioreactor in a Neural Interface System

A micro-bioreactor is developed for in vitro, controlled, growth of three-dimensional dissociated neural cultures that enables simultaneous, multipoint, electrical and fluidic interfacing, monitoring and recording of the response signals that are relevant to the studies of traumatic injury. Present experiments focus on the microfluidic system that is used to control the spatial concentration of nutrients and stimuli in the incubated tissue. The three-dimensional cellular environment in a micro-bioreactor is controlled by means of convective and diffusive fluidic processes to improve the neural cell survival rate, direct the cell growth and examine the network formation. To achieve global and local manipulation of the critical cell functions, flow within the reactor is induced from arrays of micro-machined nozzles in planar surfaces and within microscale hydrogel scaffolding. The flow and concentration fields within reactor are analyzed using microscale particle image velocimetry (PIV) and fluorescence. The flow within 25 μm thick layers between microfabricated structures is investigated using image-processing algorithms that are developed to improve spatial resolution by excluding out-of-focus particles. Mixing induced by delivery of stimuli/nutrients and waste extraction is considered by following the time-evolution and spatial propagration of the mixing front between the liquids based on the intensity of reflected light that is previously calibrated with concentration.Copyright © 2004 by ASME
Toward Understanding the Efficacy and Mechanism of Opuntia spp. as a Natural Coagulant for Potential Application in Water Treatment

Historically, there is evidence to suggest that communities in the developing world have used plant-based materials as one strategy for purifying drinking water. In this study, the coagulant properties of Opuntia spp., a species of cactus, are quantitatively evaluated for the first time. Opuntia spp. was evaluated for turbidity removal from synthetic water samples, and steps were made toward elucidating the underlying coagulation mechanism. In model turbid water using kaolin clay particles at pH 10, Opuntia spp. reduced turbidity by 98% for a range of initial turbidities. This is similar to the observed coagulation activities previously described for Moringa oleifera, a widely studied natural coagulant. Although it has been reported that Moringa oleifera predominantly operates through charge neutralization, comparison of zeta potential measurements and transmission electron microscopy images of flocs formed by Opuntia spp. suggest that these natural coagulants operate through different mechanisms. It is suggested that Opuntia spp. operates predominantly through a bridging coagulation mechanism. Once optimized, application of these readily available plants as a part of point-of-use water treatment technology may offer a practical, inexpensive, and appropriate solution for producing potable water in some developing communities.
Variation in the antlers of North American Cervalces (Mammalia; Cervidae): Review of new and previously recorded specimens

ABSTRACT A Cervalces antler rack is reported from Canton, South Dakota, and is compared with that of C. scotti from New Jersey and with other specimens from North America and Eurasia. Other new materials are reported from the Old Crow Basin, Yukon Territory, Canada, the Fairbanks area, Alaska, U.S.A., and from various localities in the eastern U.S.A. Additional measurements are given for previously recorded specimens. Known only from the Pleistocene Epoch, Cervalces possibly represented a Holarctic genus in which beam length and conformation of the tines and palmations varied considerably across its range. The genus appears to comprise two species: the North American species, C. scotti, with branching antlers whose variations are explicable either through age, maturational, geographic, or possibly stratigraphie variation; and the Eurasian species, C. latifrons, with flat palmate antlers. The specific status of the Beringian population with large antler beams is unknown, because no palmations have been rep...
Affinity Enhancement Bivalent Morpholinos for Pretargeting: Surface Plasmon Resonance Studies of Molecular Dimensions

Bivalent effectors have been reported to provide superior pretargeting by affinity enhancement. We recently reported that one bivalent MORF (phosphorodiamidate morpholino, a DNA analogue oligomer) exhibited affinity enhancement (ratio of bivalent to monovalent equilibrium constants for binding) to immobilized complementary DNA (cDNA) by surface plasmon resonance (SPR). Because bivalent effectors using oligomers are easily synthesized with molecular spacing between binding sites, an important determinant of binding, adjustable simply by selecting linkers of different dimensions and/ or lengthening or shortening the oligomer chain length, they may have advantages over existing bivalent effectors. We synthesized four bivalent MORFs with different dimensions between binding sites and measured binding affinities and affinity enhancement by SPR. An 18 mer (MORF18) was made bivalent by dimerizing both with disuccinimidyl suberate (DSS) and disuccinimidyl glutarate (DSG) linkers. By again using DSS but adding seven nonbinding adenine bases and by eliminating six binding bases, a total of four bivalent effectors, DSS-MORF12, DSG-MORF18, DSS-MORF18, and DSS-MORF25, were prepared with two different hybridization affinities (i.e. MORF12 and MORF18/ 25) and three different spacings (i.e. 20, 25, and 100 A) between binding sites. The biotinylated cDNA was immobilized on a sensor chip at 500 and 100 RU coating densities providing an average cDNA separation of 25 and 80 A. As expected, bimolecular binding dominated monomolecular binding in all cases, especially at lower MORF effector concentrations and at higher coating densities. All bivalent MORFs showed equilibrium constants superior to their monovalent form and therefore affinity enhancement. DSS-MORF25 showed the highest equilibrium constant for bimolecular binding presumably because of its larger separation between binding sites. Nevertheless, DSS-MORF12 showed the largest affinity enhancement of almost 3 orders of magnitude presumably because the shorter chain lowered the equilibrium constant for monomolecular binding. We have shown that bivalent effectors may be easily synthesized using MORF. The results provide further evidence that the use of bivalent effectors can greatly improve MORF pretargeting and, finally, that bivalent MORFs with reduced equilibrium constants may actually exhibit higher affinity enhancement.
Kinetics of fibril formation by polyalanine peptides.

Ordered β-sheet complexes, termed amyloid fibrils, are the underlying structural components of the intra- and extracellular fibrillar protein deposits that are associated with a variety of human diseases, including Alzheimer's, Parkinson's, and the prion diseases. In this work, we investigated the kinetics of fibril formation using our newly developed off-lattice intermediate resolution model, PRIME. The model is simple enough to allow the treatment of large multichain systems while maintaining a fairly realistic description of protein dynamics without built-in bias toward any conformation when used in conjunction with constant temperature discontinuous molecular dynamics, a fast alternative to conventional molecular dynamics. Simulations were performed on systems containing 48–96 model Ac-KA14K-NH2 peptides. We found that fibril formation for polyalanines incorporate features that are characteristic of three models, the templated assembly, nucleated polymerization, and nucleated conformational conversion models, but that none of them gave a completely satisfactory description of the simulation kinetics. Fibril formation was nucleation-dependent, occurring after a lag time that decreased with increasing peptide concentration and increased with increasing temperature. Fibril formation appeared to be a conformational conversion process in which small amorphous aggregates → β-sheets → ordered nucleus → subsequent rapid growth of a small stable fibril or protofilament. Fibril growth in our simulations involved both β-sheet elongation, in which the fibril grew by adding individual peptides to the end of each β-sheet, and lateral addition, in which the fibril grew by adding already formed β-sheets to its side. The initial rate of fibril formation increased with increasing concentration and decreased with increasing temperature.
Rate code and temporal code for frequency of whisker stimulation in rat primary and secondary somatic sensory cortex

We recorded responses to frequencies of whisker stimulation from 479 neurons in primary (S1) and secondary (S2) somatic sensory cortex of 26 urethane-anesthetized rats. Five whiskers on the right side of the snout were deflected with air puffs at seven frequencies between 1 and 18/s. In left S1 (barrels and septa) and S2, subsets of neurons (5%) responded to whisker stimulation across the entire range of frequencies with > or = 1 electrical discharges/ten stimuli (full responders). In contrast, 60% of the recorded cells responded above threshold only at stimulus frequencies below 6/s and 35% remained subthreshold at all frequencies tested. Thus, the full responders are unique in that they were always responsive and appeared particularly suited to facilitate a dynamic, broadband processing of stimulus frequency. Full responders were most responsive at 1 stimulus/s, and showed greatest synchrony with whisker motion at 18 stimuli/s. The barrel cells responded with the greatest temporal accuracy between 3 and 15 stimuli/s. The septum cells responded less accurately, but maintained their accuracy at all frequencies. Only septum cells continued to increase their discharge rate with increasing stimulus frequency. The S2 cells discharged with lowest temporal accuracy modulated only by stimulus frequencies < or = 6/s and exhibited the steepest decrease in discharge/stimulus with increasing stimulus frequency. Our observations suggest that full responders in the septa are well suited to encode high frequencies of whisker stimulation in timing and rate of discharge. The barrel cells, in contrast, showed the strongest temporal coding at stimulus frequencies in the middle range, and S2 cells were most sensitive to differences in low frequencies. The ubiquitous decline in discharge/stimulus in S1 and S2 may explain the decrease in blood flow observed at increasing stimulus frequency with functional imaging.