bluuebunny/crossref_metadata_2025 huggingface dataset:
Mentoring for the Educational Leadership Professoriate: Perspectives From Jay D. Scribner Mentoring Award Recipients and Mentees
Authors: Hackmann Donald G. , Malin Joel R.
Published: April 2018

This article presents findings from a study of Jay D. Scribner Award recipients. The purposes were to learn why professors engage in mentoring and to identify activities and supports provided to mentees. Interviews were held with the 12 recipients and 24 mentees who submitted letters in support of their nominations, with Mertz’s conceptual model of mentoring guiding data analysis. Findings revealed mentoring activities were based upon mentees’ career stages and institutional contexts, and aligned with Mertz’s mentoring continuum. Relationships emerged informally, included individual and group mentoring, were characterized by relational equality, and resulted in long-term research partnerships and friendships.
Drug interactions of meglitinide antidiabetics involving CYP enzymes and OATP1B1 transporter
Authors: Pakkir Maideen Naina Mohamed , Manavalan Gobinath , Balasubramanian Kumar
Published: April 2018

Meglitinides such as repaglinide and nateglinide are useful to treat type 2 diabetes patients who follow a flexible lifestyle. They are short-acting insulin secretagogues and are associated with less risk of hypoglycemia, weight gain and chronic hyperinsulinemia compared with sulfonylureas. Meglitinides are the substrates of cytochrome P450 (CYP) enzymes and organic anion transporting polypeptide 1B1 (OATP1B1 transporter) and the coadministration of the drugs affecting them will result in pharmacokinetic drug interactions. This article focuses on the drug interactions of meglitinides involving CYP enzymes and OATP1B1 transporter. To prevent the risk of hypoglycemic episodes, prescribers and pharmacists must be aware of the adverse drug interactions of meglitinides.
Unaccounted Workload Factor: Game-Day Pitch Counts in High School Baseball Pitchers—An Observational Study
Authors: Zaremski Jason L. , Zeppieri Giorgio , Jones Deborah L. , Tripp Brady L. , Bruner Michelle , Vincent Heather K. , Horodyski MaryBeth
Published: April 2018

Background:

Throwing injuries are common in high school baseball. Known risk factors include excessive pitch counts, year-round pitching, and pitching with arm pain and fatigue. Despite the evidence, the prevalence of pitching injuries among high school players has not decreased. One possibility to explain this pattern is that players accumulate unaccounted pitch volume during warm-up and bullpen activity, but this has not yet been examined.

Hypotheses:

Our primary hypothesis was that approximately 30% to 40% of pitches thrown off a mound by high school pitchers during a game-day outing are unaccounted for in current data but will be revealed when bullpen sessions and warm-up pitches are included. Our secondary hypothesis was that there is wide variability among players in the number of bullpen pitches thrown per outing.

Study Design:

Cross-sectional study; Level of evidence, 3.

Methods:

Researchers counted all pitches thrown off a mound during varsity high school baseball games played by 34 high schools in North Central Florida during the 2017 season.

Results:

We recorded 13,769 total pitches during 115 varsity high school baseball starting pitcher outings. The mean ± SD pitch numbers per game were calculated for bullpen activity (27.2 ± 9.4), warm-up (23.6 ±8.0), live games (68.9 ±19.7), and total pitches per game (119.7 ± 27.8). Thus, 42.4% of the pitches performed were not accounted for in the pitch count monitoring of these players. The number of bullpen pitches thrown varied widely among players, with 25% of participants in our data set throwing fewer than 22 pitches and 25% throwing more than 33 pitches per outing.

Conclusion:

In high school baseball players, pitch count monitoring does not account for the substantial volume of pitching that occurs during warm-up and bullpen activity during the playing season. These extra pitches should be closely monitored to help mitigate the risk of overuse injury.
Stalled for Whom? Change in the Division of Particular Housework Tasks and Their Consequences for Middle- to Low-Income Couples
Authors: Carlson Daniel L. , Miller Amanda Jayne , Sassler Sharon
Published: April 2018

Whether the gender revolution has transformed couple behavior across all social classes is the subject of ongoing scholarly debate. The authors explore cohort change in the performance of individual routine and nonroutine housework tasks among middle- to low-income couples as well as their association with several aspects of relationship quality. Data are from the second wave (1992–1994) of the National Survey of Families and Households and the 2006 Marital and Relationship Survey. Contrary to arguments of a stalled gender revolution, the authors find that contemporary couples more often share all routine tasks (other than shopping) than couples in the past, with the greatest change in dishwashing and laundry. The equal sharing of housework is more positively related to sexual intimacy and relationship satisfaction among more recent cohorts and more negatively related to marital discord. The division of dishwashing, among all tasks, is most consequential to relationship quality, especially for women.
Seismic inversion and uncertainty quantification using transdimensional Markov chain Monte Carlo method
Authors: Zhu Dehan , Gibson Richard
Published: April 2018

We applied a transdimensional stochastic inversion algorithm, reversible jump Markov chain Monte Carlo (rjMCMC), to angle-stack seismic inversion for characterization of reservoir acoustic and shear impedance with uncertainty quantification. The rjMCMC is able to infer the number of parameters for the model as well as the parameter values. In our case, the number of parameters depends on the number of model layers for a given data set. We also use this method in uncertainty quantification because a transdimensional sampling helps prevent underparameterization or strong overparameterization. An ensemble of models with proper parameterization can improve parameter estimation and uncertainty quantification. Our new results in uncertainty analysis indicate that (1) the uncertainty in seismic inversion, including uncertainty in earth properties and their locations, is related to the discontinuity of property across an interface, and (2) there is a trade-off between property uncertainty and location uncertainty. A stronger discontinuity will induce more property uncertainty but less location uncertainty at the discontinuity interface. Therefore, we further use the inversion uncertainty as a novel seismic attribute to assist in delineation of subsurface discontinuity interfaces and quantify the magnitude of the discontinuities, which further facilitates quantitative interpretation and stratigraphic interpretation.
Characterization of the novel mitochondrial genome replication factor MiRF172 in Trypanosoma brucei
Authors: Amodeo Simona , Jakob Martin , Ochsenreiter Torsten
Published: April 2018

The unicellular parasite Trypanosoma brucei harbors one mitochondrial organelle with a singular genome called the kinetoplast DNA (kDNA). The kDNA consists of a network of concatenated minicircles and a few maxicircles that form the kDNA disc. More than 30 proteins involved in kDNA replication have been described. However, several mechanistic questions are only poorly understood. Here, we describe and characterize minicircle replication factor 172 (MiRF172), a novel mitochondrial genome replication factor that is essential for cell growth and kDNA maintenance. By performing super-resolution microscopy, we show that MiRF172 is localized to the kDNA disc, facing the region between the genome and the mitochondrial membranes. We demonstrate that depletion of MiRF172 leads to a loss of minicircles and maxicircles. Detailed analysis suggests that MiRF172 is involved in the reattachment of replicated minicircles to the kDNA disc. Furthermore, we provide evidence that the localization of the replication factor MiRF172 not only depends on the kDNA itself, but also on the mitochondrial genome segregation machinery, suggesting an interaction between the two essential entities.

This article has an associated First Person interview with the first author of the paper.
Based on the perceptions of community stakeholders, how can adolescent pregnancies be prevented? A qualitative study
Authors: Phuhongsai Sadudee , Pinitsoontorn Somdej
Published: April 2018

Background: Adolescent pregnancy an important problem in adolescent health and government agencies need to focus on solving problem. The purpose of this research was to survey the perceptions of community stakeholders concerning the prevention of adolescent pregnancies in rural communities.

Methods:Data collection was performed using group meetings with 103 stakeholders involved in adolescent pregnancy prevention. They were nurses, public health officials, parents or guardians, students, teachers, public health volunteers and community leaders. Thematic analysis indicated work on adolescent pregnancy prevention problems in rural areas was carried out by only some agencies such as district and sub-district health promoting hospitals, providing youth-friendly health service clinics and educating student leaders in schools on sex education.

Results: Collectively, these results draw attention to the need for an appropriate program to strengthen adolescent, family and practitioner skills for the prevention of teenage pregnancies. Schools provide sex education as part of a health education curriculum, and some schools provide additional instruction in guidance classes. Problems from inconsistent work when networks fail were encountered. Stakeholders believe adolescent pregnancy prevention should focus on the following: (1) adolescents should receive training for skill development with content related to knowledge about sex, negotiation, refusal, morality and ethics, (2) teachers should receive training on comprehensive sexual education, and, (3) families should work to improve their communication on sexual health and development

Conclusions: There is a strong need for families to develop the ability to communicate with each other about sexuality and reproductive health. Developing parenting skills on how and when to talk about sex with their adolescents and open parental communication on sexuality issues at home is necessary. Activities need to also be developed for adolescents who are more inclined to engage in risky sexual behaviors.
Authoring Bioconductor workflows with BiocWorkflowTools
Authors: Smith Mike L. , Oleś Andrzej K. , Huber Wolfgang
Published: April 2018

The Bioconductor Gateway on the F1000Research platform is a channel for peer-reviewed and citable publication of end-to-end data analysis workflows rooted in the Bioconductor ecosystem. In addition to the largely static journal publication, it is hoped that authors will also deposit their workflows as executable documents on Bioconductor, where the benefits of regular code testing and easy updating can be realized. Ideally these two endpoints would be met from a single source document. However, so far this has not been easy, due to lack of a technical solution that meets both the requirements of the F1000Research article submission format and the executable documents on Bioconductor.

Submission to the platform requires a LaTeX file, which many authors traditionally have produced by writing an Rnw document for Sweave or knitr. On the other hand, to produce the HTML rendering of the document hosted by Bioconductor, the most straightforward starting point is the R Markdown format. Tools such as pandoc enable conversion between many formats, but typically a high degree of manual intervention used to be required to satisfactorily handle aspects such as floating figures, cross-references, literature references, and author affiliations. The BiocWorkflowTools package aims to solve this problem by enabling authors to work with R Markdown right up until the moment they wish to submit to the platform.
On the Threshold of a «Digital» Future of Russia
Authors: Егорушкина Т. , Egorushkina T. , Логвинов Сергей , Logvinov Syergyey , Швецов Сергей , Shvetsov Sergey
Published: April 2018

The article presents the analysis of approaches to definition of the “digital economy”, “digitalization” which should be the future stage in the development of global socio-economic system through the transformation of all spheres of human activity. Considers preconditions and features of development of the digital economy in Russia and abroad. The attention is paid at factors determining the importance of the digital economy and digitalization for economic growth and competitiveness in the new technological way.
The Systemic Problems of the Customs Policy of Russia
Authors: Быстров Г. , Bystrov G.
Published: April 2018

The current systemic problems of formation and development of the customs policy are formulated: customs regulation and the innovative nature of reproduction, the formation of the structure of the domestic market in terms of sanctions, the harmonization of relations in the EEA. The thesis of the necessity of including a mechanism of customs policy of institutional control, responsible for the innovation economy, and evaluation of the results of customs activities according to its contribution to the innovative development of Russia is justified.
Fundamentals of the strategy of managing the formation of human capital in mod-ern Russia
Authors: Басовская Елена , Basovskaya Elena , Басовский Леонид , Basovskiy Leonid , Ломовцев Д. , Lomovcev D.
Published: April 2018

In the modern economy of Russia, the level of remuneration of workers with higher education significantly exceeds the average level of wages. The level of remuneration of workers with a secondary vocational education practically does not exceed the average level of remuneration for workers with a secondary general education. The level of remuneration of workers having an average professional and general education significantly reduced in relation to the average level of remuneration. The influence of practical experience on the accumulation of human experience is significantly reduced. The most important role in the formation of human capital has a higher education, which allows obtaining fundamental training. The formation of a lower level, which does not provide fundamental training, experience in practical work, is losing its significance.
Strategic Planning of Human Capital Development in Industrial Enterprises
Authors: Буткенова Алия , Butkenova Aliya
Published: April 2018

Relevance of the subject matter is caused by the demand of the modern society for high quality workforce, the personneltosolve the tasks of industry and production development particularly in the Republic of Kazakhstan. Therewith, if in the era of industrialization the demand for “gun hands” was high, while the engineering personnel was not so demanded, then in the modern period the need for qualified personnel capable of solving complicated and often unusual tasks is significantly increasing. The demand for semi-skilled employees decreases because of development of the technologies and labor means replacing human workforce. Knowledge, skillsand competences of employees, necessary for modern production sector, become an important factor of the industry. It happens due to the fact that such knowledge, skillsand competences a recurrently required not only from engineeringemployees, manager sand office-management personnel, but also from the employees who should be able to work with the modern equipment by modern technologies. Objective of the Study: The objective of the paper is to study the formation of human capital assets, strategic planning of human capital assets at the modern industrial enterprises of Kazakhstan. Methods of the Study: The leading method for studying the subject matter is strategic analysis(according to the data of the KazStat (RK statistical agency) and other strategic data), as well as selective questionnaires (poll) of the heads of the enterprises. Results of the Study: This paper represents the main approaches to the notion of “human capital assets”. It has been defined that it is a potential of enterprise, i.e. the capacity of the work force to solve both the current and perspective tasks connected with the development. Practical Significance: The materials of the paperrepresent practical value for the industrial enterprises of both Kazakhstan and other countries on the part of the activities connected with personnel management.
PERFILES DOCENTES UNIVERSITARIOS: CONOCIMIENTO Y USO PROFESIONAL DEL SMARTPHONE
Authors: Salcines Talledo Irina , González Fernández Natalia , Briones Pérez Elena
Published: April 2018

INTRODUCCIÓN. La inmersión de las tecnologías de la información y la comunicación (TIC) en las aulas universitarias ha transformado las tradicionales dinámicas pedagógicas. Dispositivos móviles como el smartphone ofrecen múltiples posibilidades educativas para los docentes que se convierten en gestores, facilitadores y promotores de prácticas educativas de mobile learning mediadas por dispositivos como el smartphone. MÉTODO. El propósito de la investigación es ofrecer una clasificación de perfiles docentes relacionados con el conocimiento y uso de los smartphones, así como analizar su relación con el interés hacia la formación y el uso del dispositivo como recurso pedagógico en sus clases. Para ello se realizó un análisis de conglomerados, que permitió establecer perfiles y, mediante pruebas no parámetricas se analizó la significación respecto al interés hacia la formación y desarrollo de experiencias educativas. RESULTADOS. Los resultados indican la existencia de tres perfiles docentes denominados: impulsores del smartphone en tareas profesionales; iniciados profesionalmente en el smartphone y usuarios no profesionales del smartphone. El primer perfil es el que muestra un mayor interés hacia la formación y el que ha desarrollado más experiencias educativas con el smartphone. DISCUSIÓN. Esta clasificación de docentes en tres perfiles, al igual que en las investigaciones previas, no establece diferencias significativas relativas al género y se gradúa en función de la profundidad y habilidad en el uso y manejo de los recursos tecnológicos. Igualmente, los resultados permiten aventurar las características de una formación tecnológica dirigida a potenciar el uso profesional del smartphone en la educación superior para optimizar sus posibilidades educativas.
Ecotourism development to preserve mangrove conservation effort: Case study in Margasari Village, District of East Lampung, Indonesia
Authors: SETIAWAN WAWAN , HARIANTO SUGENG P. , QURNIATI ROMMY
Published: April 2018

Setiawan W, Harianto SP, Rommy Qurniati R. 2017. Ecotourism development to preserve mangrove conservation effort: Case study in Margasari Village, District of East Lampung, Indonesia. Ocean Life 1: 14-19. The conservation efforts by Margasari community have produced the enhancement of mangrove forest areas, however the utilization of mangrove forest by people around was low. To make the conservation effort sustainable needs to develop mangrove ecotourism so they can utilize mangrove forest existence. This research intended to study the conservation and ecotourism effort in Margasari Village and the community perception of ecotourism development. This research was conducted in March-April 2017 in Margasari Village by interviewing 96 respondents. The data collection was undertaken through field observation, key informant interviews, and structured interviews with questionnaire. The result showed, the conservation effort was protecting, preserving, and utilizing of mangrove such as mangrove nursery, mangrove plantation, utilizing of jeruju and pedada fruit as food and counselling to the villagers not to cut mangrove and enter the mangrove forest. The ecotourism activities were boating around the mangrove, mangrove planting tourism, and bird watching. The conservation and ecotourism effort conduct by the people who joined community groups. But it was dominated by the group manager. So the financial benefit from ecotourism had limited for few people. Nevertheless, Margasari community agreed with the ecotourism development and was willing to participate in developing the ecotourism.
Using virtualization to protect the proprietary material science applications in volunteer computing
Authors: Khrapov Nikolay P. , Rozen Valery V. , Samtsevich Artem I. , Posypkin Mikhail A. , Sukhomlin Vladimir A. , Oganov Artem R.
Published: April 2018

USPEX is a world-leading software for computational material design. In essence, USPEX splits simulation into a large number of workunits that can be processed independently. This scheme ideally fits the desktop grid architecture. Workunit processing is done by a simulation package aimed at energy minimization. Many of such packages are proprietary and should be protected from unauthorized access when running on a volunteer PC. In this paper we present an original approach based on virtualization. In a nutshell, the proprietary code and input files are stored in an encrypted folder and run inside a virtual machine image that is also password protected. The paper describes this approach in detail and discusses its application in USPEX@home volunteer project.
A Miniaturized Dual-Band FSS with Closely Spaced Resonances Using 2.5-Dimension Structure
Authors: Yin Weiyang , Zhang Hou , Zhong Tao , Min Xueliang
Published: April 2018

Using 2.5-dimension structure, a novel miniaturized dual-band FSS with closely spaced resonances is proposed in the paper. The special design of the geometry contributes to two closely spaced resonances at 1.69 GHz and 2.16 GHz respectively and the frequency ratio of upper to the lower resonant frequency is 1.27. Besides, the two bands can be controlled individually by varying corresponding parameters. The size of the proposed FSS is only 0.057λ0, where the λ0 represents free space wavelength at lower resonant band. Furthermore, the simulation results show the proposed FSS exhibits stable response with different incident angles and polarizations. To understand the design better, the distribution of surface current is analyzed to explain the operating mechanism of the proposed FSS. Finally, the proposed FSS is fabricated and the measurement results are in accordance with the simulation results.
On the Rellich inequality in L p(·)(a,b)
Authors: Edmunds David , Meskhi Alexander
Published: April 2018

In this note we prove a one-dimensional Rellich inequality in variable exponent Lebesgue spaces, with exponents that satisfy a condition of log-Hölder type.
Application of Rothe's method to a semilinear hyperbolic equation
Authors: Bouziani Abdelfatah
Published: April 2018

In this paper, we consider a problem for a semilinear hyperbolic equation. The existence, uniqueness and continuous dependence of a solution upon the data are proved by Rothe's method. Besides, some convergence results are established for approximations.
Existence results for semilinear neutral functional differential equations involving evolution operators in Fréchet spaces
Authors: Baghli Selma , Benchohra Mouffak
Published: April 2018

The existence of a unique mild solution on a semiinfinite interval for a first order semilinear neutral functional differential equations involving evolution operators in Fréchet spaces is investigating using a nonlinear alternative of Leray–Schauder type for contractive maps, combined with semigroup theory.
A Comparison of Simplified Two-dimensional Flow Models Exemplified by Water Flow in a Cavern
Authors: Prybytak Dzmitry , Zima Piotr
Published: April 2018

The paper shows the results of a comparison of simplified models describing a two-dimensional water flow in the example of a water flow through a straight channel sector with a cavern. The following models were tested: the two-dimensional potential flow model, the Stokes model and the Navier-Stokes model. In order to solve the first two, the boundary element method was employed, whereas to solve the Navier-Stokes equations, the open-source code library OpenFOAM was applied. The results of numerical solutions were compared with the results of measurements carried out on a test stand in a hydraulic laboratory. The measurements were taken with an ADV probe (Acoustic Doppler Velocimeter). Finally, differences between the results obtained from the mathematical models and the results of laboratory measurements were analysed.
Clinical analyses of 383 cases with maternal cardiac diseases
Authors: Aydin Emine , Ozyuncu Ozgur , Kasapoglu Dila , Orgul Gokcen , Ozer Necla , Yurdakok Murat , Beksac M. Sinan
Published: April 2018

Aim:

To evaluate the pregnancy outcomes of women with heart disease.

Materials and methods:

In this retrospective study, 383 pregnant women with cardiac diseases were examined. The cases were classified according to the World Health Organization (WHO) classification. The distribution of the cases according to class, congenital heart diseases, mean birthweight, mean gestational week at delivery, type of delivery [cesarean section (CS) or vaginal delivery], and cardivascular events (during pregnancy and puerperium) were evaluated.

Results:

Of the 383 patients, 25 were in Class I; 39, Class II; 255, Class II or III; 31, Class III; and 33, Class IV cardiac diseases. The neonatal birth weights were significantly lower in Class III than in Classes II, and II or III. The preterm delivery rate was higher in Class III than in the other classes. Delivery was performed by CS due to cardiac indications in the high-risk classes, however, only obstetric indications were considered in the low-risk classes. Only one case of maternal death occurred during the postpartum period, in a patient with Eisenmenger’s syndrome.

Discussion:

Cardiovascular diseases are an important cause of mortality and morbidity in pregnancy. The adverse impact of cardiovascular disorders on pregnancy outcomes should be the main concern during the management of these women.
Guest-driven unusual conformations in two calix[6]arene solvates and a new calix[8]arene
Authors: Martins Felipe Terra , da Silva Maia Angélica Faleiros , dos Santos Fernando Machado , Alvarenga Meiry Edivirges , Ribeiro Leandro , da Silva Neto Leonardo , de Fátima Ângelo
Published: April 2018

Unusual conformations have been found in a new calix[8]arene and in new solvates of two known calix[6]arenes. The chair-like conformation with 2/m point group symmetry was found for the first time in the dimethylformamide (DMF) disolvate of the basic calix[6]arene (1) without substituents in the lower and upper rims. Such symmetry is driven by the guest geometry allowing for two equivalent hydrogen bonding patterns in the chair seat. This avoids cone distortion found in the other chair-like conformers, although they have energies lower than that of new symmetrical conformer. The molecular conformation of hexa(carboxymethoxy)calix[6]arene (2) is also described as a dimethylsulfoxide (DMSO) pentasolvate. Its conformation can be described as a 1,3,5-closed cone with three alternate phenyl rings inclined inwards to the cone, thereby closing the cone entrance. Such a conformation also suggests five acid groups are pointed towards the same side of the calyx base and are able to bind metal ions or basic compounds in the lower rim, while inclusion of guests into the cone cavity is hindered. Both inclusion and cooperative acid binding/coordination abilities are still more hindered in the lowest energy 1,2,3-alternate cone conformer of 2. The role of the solvent in avoiding cone distortion was highlighted by inspecting the conformations of 5,11,17,23,29,35,41,47-octanitro-49,50,51,52,53,54,55,56-octa-n-butoxycalix[8]arene (3) and the known nitro analogues having methyl instead of n-butyl groups. Cone distortion is found in the non-solvated crystal form of 3, while non-classical hydrogen bonds with tetrahydrofuran preclude this in the literature analogue.
Oblique Propagation of Electrostatic Waves in a Magnetized Electron-Positron-Ion Plasma in the Presence of Heavy Particles
Authors: Sarker M. , Hossen M. R. , Shah M. G. , Hosen B. , Mamun A. A.
Published: April 2018

A theoretical investigation is carried out to understand the basic features of nonlinear propagation of heavy ion-acoustic (HIA) waves subjected to an external magnetic field in an electron-positron-ion plasma that consists of cold magnetized positively charged heavy ion fluids and superthermal distributed electrons and positrons. In the nonlinear regime, the Korteweg-de Vries (K-dV) and modified K-dV (mK-dV) equations describing the propagation of HIA waves are derived. The latter admits a solitary wave solution with both positive and negative potentials (for K-dV equation) and only positive potential (for mK-dV equation) in the weak amplitude limit. It is observed that the effects of external magnetic field (obliqueness), superthermal electrons and positrons, different plasma species concentration, heavy ion dynamics, and temperature ratio significantly modify the basic features of HIA solitary waves. The application of the results in a magnetized EPI plasma, which occurs in many astrophysical objects (e.g. pulsars, cluster explosions, and active galactic nuclei) is briefly discussed.
Neurophysiological correlates of hand preference in primary motor cortex of adult squirrel monkeys
Authors: Nudo RJ , Jenkins WM , Merzenich MM , Prejean T , Grenda R
Published: April 2018

Variability in the functional topography of area 4 was examined in adult squirrel monkeys. Conventional intracortical microstimulation techniques were used to derive detailed maps (250 microns interpenetration distances) of distal forelimb movement representations in both hemispheres of six monkeys. Spatial features of these representational maps were then compared to the hand preferred by the individual animals during a motor task requiring skilled digit use. Beyond a few broad generalizations common to all area 4 motor maps, the local mosaic-like topography of individual distal forelimb representations was highly idiosyncratic. Using statistical procedures to determine the independent contributions of individual, side, and movement category to the total variation in motor maps, the results demonstrate statistically significant variation in representational topography among individuals as well as between hemispheres of the same individuals. In the dominant hemisphere (i.e., the hemisphere opposite the preferred hand), the distal forelimb representations generally were greater in number and larger in total area, and displayed a longer total boundary length and a greater index of spatial complexity. Because of the direct relationship between interhemispheric asymmetry and behavioral asymmetry, these studies suggest that a large source of variability found in the topography of motor maps in this and other studies derives from differences in the way particular movements and/or movement combinations are performed by individual animals.
NMDA and non-NMDA receptor-mediated increase of c-fos mRNA in dentate gyrus neurons involves calcium influx via different routes
Authors: Lerea LS , Butler LS , McNamara JO
Published: April 2018

We examined the effects of selective agonists of ionotropic excitatory amino acid (EAA) receptor subtypes on induction of the immediate early gene c-fos. We used in situ hybridization to measure c-fos mRNA and fura-2 imaging to measure intracellular calcium (Ca2+i) in individual dentate gyrus neurons maintained in vitro. Activation of either NMDA or non-NMDA receptor subtypes is sufficient to induce the rapid and dramatic increase of c-fos mRNA. Activation of either NMDA or non-NMDA receptors also induces a rapid and dramatic increase of Ca2+i, effects blocked by the removal or chelation of extracellular calcium (Ca2+e). c- fos mRNA induction by either receptor subtype is Ca2+ dependent, since chelation of Ca2+e with EGTA prevents c-fos mRNA induction by both NMDA and non-NMDA receptor agonists. The increase in Ca2+i induced by activating non-NMDA receptors is inhibited either by removal of extracellular sodium (Na+e) or by the voltage-sensitive calcium channel (VSCC) blocker nifedipine. By contrast, the increase of Ca2+i induced by activating NMDA receptors is not inhibited by removal of Na+e or nifedipine. Consistent with these effects on Ca2+i, nifedipine inhibits induction of c-fos mRNA by non-NMDA, but not by NMDA, receptor agonists. These findings indicate that Ca2+ serves as a second messenger coupling ionotropic EAA receptors with transcriptional activation of c-fos mRNA. The route of Ca2+ entry into dentate neurons, however, depends on the EAA receptor subtype stimulated. Non-NMDA receptor activation results in Ca2+ influx indirectly via VSCCs, whereas NMDA receptor activation results in Ca2+ influx directly through the NMDA channel itself.(ABSTRACT TRUNCATED AT 250 WORDS)
Divalent-selective voltage-independent calcium channels in Lymnaea neurons: permeation properties and inhibition by intracellular magnesium
Authors: Strong JA , Scott SA
Published: April 2018

Calcium channels are tightly regulated. Voltage-gated calcium channels open only in response to depolarization, while voltage-independent calcium channels usually open only in response to specific intracellular or extracellular ligands. Voltage-independent calcium channels have been described in several invertebrate neurons. One difficulty in understanding the function of the neuronal channels is that their regulators are unknown. They open rarely in intact cells but are activated by formation of a cell-free patch, suggesting that some intracellular inhibitor usually keeps them closed. This article provides evidence that intracellular Mg2+ is one important regulator of the voltage-independent calcium channel (HP channel) in neurons of the pond snail Lymnaea stagnalis. Mg2+ (1 mM) rapidly and reversibly inhibited activity of this calcium channel when applied to the intracellular side of cell-free membrane patches. The primary effect of the Mg2+ was to promote long closings of the channel. The mechanism of the intracellular Mg2+ inhibition is distinct from open channel block, a phenomenon seen in a variety of cation channels. Open channel block can also be seen in the HP channels, but only at very positive membrane potentials. Some of the permeability and selectivity characteristics of these channels were also examined. The channels are permeable to Mg2+ and Ca2+ as well as Ba2+. Outward currents carried by monovalent cations can be observed only at very positive membrane potentials, indicating high selectivity for divalent over monovalent cations. The single channel current-voltage relationship is markedly nonlinear, becoming quite shallow near the reversal potential, and hence is qualitatively similar to that seen in many voltage-activated calcium channels.
Heat shock protein expression in vulnerable cells of the rat hippocampus as an indicator of excitation-induced neuronal stress
Authors: Sloviter RS , Lowenstein DH
Published: April 2018

The inducible 72 kDa heat shock protein (HSP72) has been shown to be protective in non-neuronal cells and neurons in culture, but its function and the control of its expression in the CNS are poorly understood. Although HSP72 is induced in neurons in vivo by neurotoxic compounds that produce seizures and neuronal damage, it is unknown if its expression is a specific response to excitation per se or to “tressful” or potentially injurious excitation, or if it is a marker or mediator of irreversible injury. We have attempted to identify the nature of the stimulus for HSP72 expression by utilizing focal electrical stimulation that can either excite or destroy postsynaptic cells, depending on the duration of afferent stimulation. Previous studies have demonstrated that intermittent stimulation of the main hippocampal afferent pathway for 24 hr evokes synchronous discharges in dentate granule cells but does not injure them. However, the same stimulation irreversibly destroys three of the four cell populations innervated by the granule cells. The three vulnerable populations are the dentate hilar mossy cells, the somatostatin/neuropeptide Y (NPY)- immunoreactive hilar neurons, and the CA3c pyramidal cells. The fourth and relatively resistant population is the GABA-immunoreactive dentate basket cells. In this study, we have localized HSP72 expression immunocytochemically in the hippocampal dentate gyrus in response to nontoxic durations of potentially neurotoxic afferent stimulation.(ABSTRACT TRUNCATED AT 250 WORDS)
Orientation selectivity, preference, and continuity in monkey striate cortex
Authors: Blasdel GG
Published: April 2018

Maps of orientation preference and selectivity, inferred from differential images of orientation (Blasdel, 1992), reveal linear organizations in patches, 0.5-1.0 mm across, where orientation selectivities are high, and where preferred orientations rotate linearly along one axis while remaining constant along the other. Most of these linear zones lie between the centers of adjacent ocular dominance columns, with their short iso-orientation slabs oriented perpendicular, in regions enjoying the greatest binocular overlap. These two-dimensional linear zones are segregated by one- and zero- dimensional discontinuities that are particularly abundant in the centers of ocular dominance columns, and that are also correlated with cytochrome oxidase-rich zones within them. Discontinuities smaller than 90 degrees extend in one dimension, as fractures, while discontinuities greater than 90 degrees are confined to points, in the form of singularities, that are generated when orientation preferences rotate continuously through +/- 180 degrees along circular paths. The continuous rotations through 180 degrees imply that direction preferences are not organized laterally in striate cortex. And they also ensure that preferences for all orientations converge at each singularity, with perpendicular orientations represented uniquely close together on opposite sides. The periodic interspersing of linear zones and singularities suggests that orientation preferences are organized by at least two competing schemes. They are optimized for linearity, along with selectivity and binocularity, in the linear zones, and they are optimized for density near singularities. Since upper-layer neurons are likely to have similarly sized dendritic fields in all regions (Lund and Yoshioka, 1991), those in the linear zones should receive precise information about narrowly constrained orientations, while those near singularities should receive coarse information about all orientations--very different inputs that suggest different perceptual functions.
Calcium-induced translocation of synaptic vesicles to the active site
Authors: Koenig JH , Yamaoka K , Ikeda K
Published: April 2018

The effect of increasing [Ca2+]o on the positioning of synaptic vesicles relative to the active site in resting coxal neuromuscular junctions of Drosophila was investigated. In normal saline (1.8 mM Ca2+) only a very small percentage of sites possess a vesicle docked under the dense body plate close to the plasma membrane in a readily releasable position. However, after exposure to elevated Ca2+ salines (3.6, 9, 18 mM), an increase in the number of active sites possessing docked vesicles was observed. Also, an increase in the average number of docked vesicles/site was seen. Intracellular recordings from coxal muscle fibers in normal saline and elevated Ca2+ salines were made, and it was observed that exposure to elevated Ca2+ saline caused an increase in miniature excitatory junction potential (mejp) frequency and in multiquantal and clustered mejps. Thus, when the number of active sites possessing docked vesicles increases, the frequency of spontaneous release also increases. Furthermore, when the number of docked vesicles/site increases, the number of multiquantal mejps increases. The data suggest that Ca2+ may be involved in vesicle translocation to the active site, and that the concentration of Ca2+ in the terminal may regulate the number of active sites that possess readily releasable vesicles. The effects of increasing the number of docked vesicles on spontaneous release characteristics are discussed.
Patch-clamp analysis of spontaneous synaptic currents in supraoptic neuroendocrine cells of the rat hypothalamus
Authors: Wuarin JP , Dudek FE
Published: April 2018

Spontaneous synaptic currents were recorded in supraoptic magnocellular neurosecretory cells using whole-cell patch-clamp techniques in the rat hypothalamic slice preparation. Numerous spontaneous excitatory and inhibitory postsynaptic currents (EPSCs and IPSCs) were observed in the 27 cells recorded. The rate of occurrence of the spontaneous currents and the relative proportion of EPSCs versus IPSCs varied significantly from cell to cell. Miniature EPSCs and IPSCs were clearly distinguished from background noise in TTX (n = 3 cells at 0.5 micrograms/ml). The frequency of EPSCs and IPSCs decreased by approximately 70% and the largest events were blocked in TTX, but the peaks of the amplitude histograms were shifted by only a few picoamperes. Bicuculline (n = 10 cells at 10 microM and 2 cells at 20 microM) blocked completely all the IPSCs without any detectable effect on the frequency or amplitude of the EPSCs. No slow spontaneous outward currents, indicative of a K+ current from activation of GABAB receptors, were observed. The alpha- amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)/kainate-type glutamate receptor antagonist 6-cyano-2,3-dihydroxy-7-nitroquinoxaline (CNQX; n = 7 cells at 10 microM) consistently blocked all EPSCs without any apparent effect on the frequency or amplitude of the IPSCs. No synaptic events could be detected when CNQX was applied in combination with bicuculline (n = 4). The decay phase of averaged spontaneous IPSCs and EPSCs recorded at resting membrane potential could be well fitted by single exponential functions in most cells. The time constants ranged from 0.92 to 3.0 msec for EPSCs (five cells) and from 5.3 to 6.6 msec for IPSCs (four cells). A second, slower time constant of 4–15 msec was found in the largest averaged EPSCs (> or = 40 pA). The amplitude of this slow component was -2 to -4 pA. These results suggest that, in the in vitro slice preparation, glutamate mediates all the spontaneous EPSCs in magnocellular neurosecretory cells by acting primarily on AMPA/kainate-type receptors at resting membrane potential and that activation of GABAA receptors mediates most if not all IPSCs.
Highly polysialylated neural cell adhesion molecule (NCAM-H) is expressed by newly generated granule cells in the dentate gyrus of the adult rat
Authors: Seki T , Arai Y
Published: April 2018

We have found in the adult rat that the persistent expression of a highly polysialylated neural cell adhesion molecule (NCAM-H) that is generally specific to developing tissues, remains restrictively in the cells of the deepest portion of the dentate granular layer. Since the granule cells are known to continue to be generated in this region during the adult period, we have tried to determine whether NCAM-H is expressed by newly generated granule cells. Immunoelectron microscopic observation revealed that about half of the NCAM-H-expressing cells had the features of dentate granule cells, and that the rest of these cells appeared to be immature cells. Double immunostaining for NCAM-H and glial fibrillary acidic protein (GFAP) revealed that the NCAM-H- expressing cells differed from GFAP-positive glial cells. In rats injected with 5-bromo-2′-deoxyuridine (BrdU) at post-natal day 35, double immunostaining for NCAM-H and BrdU demonstrated that the BrdU- labeled cells expressed NCAM-H at 12 d after the injection but not at 80 d. These results provide the first direct evidence that NCAM-H is expressed transiently by newly generated granule cells that may add new neuronal circuits to the adult hippocampal formation.
Pseudorabies virus infection of the rat central nervous system: ultrastructural characterization of viral replication, transport, and pathogenesis
Authors: Card JP , Rinaman L , Lynn RB , Lee BH , Meade RP , Miselis RR , Enquist LW
Published: April 2018

Pseudorabies virus (PRV) has been used extensively to map synaptic circuits in the CNS and PNS. A fundamental assumption of these studies is that the virus replicates within synaptically linked populations of neurons and does not spread through the extracellular space or by cell- to-cell fusion. In the present analysis we have used electron microscopy to characterize pathways of viral replication and egress that lead to transneuronal infection of neurons, and to document the non-neuronal response to neuronal infection. Three strains of PRV that differ in virulence were used to infect preganglionic motor neurons in the dorsal motor nucleus of the vagus (DMV). The data demonstrate that viral replication and transneuronal passage occur in a stepwise fashion that utilizes existing cellular processes, and that the non-neuronal response to infection serves to restrict nonspecific spread of virus by isolating severely infected neurons. Specifically, capsids containing viral DNA replicate in the cell nucleus, traverse the endoplasmic reticulum to gain access to the cytoplasm, and acquire a bilaminar membrane envelope from the trans cisternae of the Golgi. The outer leaf of this envelope fuses with the neuron membrane to release virus adjacent to axon terminals that synapse upon the infected cell. A second fusion event involving the viral envelope and the afferent terminal releases the naked capsid into the bouton. Systematic analysis of serial sections demonstrated that release of virus from infected neurons occurs preferentially at sites of afferent contact. Nonspecific diffusion of virus from even the most severely infected cells is restricted by astrocytes and other non-neuronal elements that are mobilized to the site of viral infectivity. The ability of glia and macrophages to restrict spread of virus from necrotic neurons is the product of (1) temporal differences in the mobilization of these cells to the site of infection, (2) differential susceptibility of these cells to PRV infection, and (3) abortive viral replication in cells that are permissive for infection. The findings provide further insight into the intracellular routes of viral assembly and egress and support the contention that transneuronal spread of virus in the brain results from specific passage of virions through synaptically linked neurons rather than through cell fusion or release of virus into the extracellular space.
Increase of tryptophan hydroxylase enzyme protein by dexamethasone in adrenalectomized rat midbrain
Authors: Azmitia EC , Liao B , Chen YS
Published: April 2018

Using two specific anti-peptide antibodies (WH-66 and WH-412) against tryptophan hydroxylase (TPH or WH), a single principle band from the midbrain raphe area was seen (approximately 49 kDa) in immunoblots. Densitometric comparison of the immunoreactivity of the 49 kDa band was greater (50–75%) in immunoblots of midbrain raphe samples from adrenalectomized (ADX) rats given dexamethasone (DEX) in their drinking water (10 mg/liter) for 12–96 hr. No difference from ADX brains was seen in the 49 kDa band after only 4 hr of exposure to DEX in the drinking water. Immunocytochemical staining with WH-66 of sections from rat brainstem showed specific cellular staining in all of the serotonergic raphe nuclei but not in substantia nigra or locus coeruleus. More cellular staining of WH-66-immunoreactive (WH-66-IR) cells was observed in the dorsal and median raphe nuclei in ADX rats given DEX for 72 hr, especially in the perikarya and in the primary dendrites. Quantification of staining per cell soma with an automatic image analyzer indicates that amount of WH-66-IR in neurons from both the lateral wing subdivision of the dorsal raphe nucleus and in the supralemniscal nucleus, B-9, was 80% higher in the ADX+DEX compared to ADX animals. Interestingly, morphometric analysis of these same cells showed a corresponding increase of 37–80% in somal area. It is suggested that a part of the increase in TPH/WH staining may be a consequence of cellular hypertrophy due to DEX treatment of the ADX rats.