bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of Risk Factors for Injury in Women's Collegiate Gymnastics With the Gymnastics Functional Measurement Tool
Authors: Ling Daphne , Sleeper Mark , Casey Ellen
Published: May 2019

Background

The Gymnastics Functional Measurement Tool (GFMT) is a series of 10 sport‐specific tests that evaluates the physical fitness of female gymnasts. The standardized scoring system has been validated in a wide range of competitive levels. To date, there is no screening tool to identify risk factors for injury in female gymnasts.

Objective

To determine if the total score on the GFMT or the individual test components can identify female collegiate gymnasts who are at risk of developing an injury.

Design

Prospective cohort study.

Setting

Collegiate gymnastics training and competition facilities.

Participants

One hundred female gymnasts from seven National Collegiate Athletic Association, Division I teams.

Interventions

Gymnasts were tested with the GFMT (vertical jump, hanging leg lifts, agility sprint, 20‐meter sprint, pull‐ups, push‐ups, rope climb, handstand hold, lower extremity flexibility, and shoulder flexibility). Each team's certified athletic trainer recorded injuries over the course of one season. Logistic regression modeling was used to assess the relationship between each individual test and the development of upper extremity, lower extremity, or trunk injuries.

Main Outcome Measurements

Gymnastics‐related injuries.

Results

A total of 160 injuries from 100 gymnasts were included in the analysis. No tests were significantly associated with developing of upper or lower extremity injuries. A higher score on the vertical jump test was associated with fewer trunk injuries (odds ratio [OR] 0.69, 95% confidence interval [CI] 0.52‐0.91; P = .01). This relationship existed even after adjusting for gymnast characteristics in a multivariable analysis.

Conclusions

A one‐unit increase in vertical jump score was associated with a 30% decrease in trunk injuries in collegiate‐level female gymnasts. Future research to identify risk factors for gymnastics‐related injury and methods for prevention are needed.

Level of Evidence

II.
Key Role of Microtubule and Its Acetylation in a Zinc Oxide Nanoparticle–Mediated Lysosome–Autophagy System
Authors: Liu Jia , Kang Yiyuan , Yin Suhan , Chen Aijie , Wu Junrong , Liang Huimin , Shao Longquan
Published: May 2019

Autophagy is a biological process that has attracted considerable attention as a target for novel therapeutics. Recently, nanomaterials (NMs) have been reported to modulate autophagy, which makes them potential agents for the treatment of autophagy‐related diseases. In this study, zinc oxide nanoparticles (ZNPs) are utilized to evaluate NM‐induced autophagy and debate the mechanisms involved. It is found that ZNPs undergo pH‐dependent ion shedding and that intracellular zinc ions (Zn2+) play a crucial role in autophagy. Autophagy is activated with ZNPs treatment, which is inhibited after Zn2+ sequestration via ethylenediamine tetra‐acetic acid. Lysosome‐based autophagic degradation is halted after ZNPs treatment for more than 3 h and is accompanied by blockage of lysophagy, which renews impaired lysosomes. Furthermore, the microtubule (MT) system participates in ZNP‐induced lysosome–autophagy system changes, especially in the fusion between autophagosomes and lysosomes. MT acetylation is helpful for protecting from ZNP‐induced MT disruption, and it promotes the autophagic degradation process. In conclusion, this study provides valuable information on NM‐induced lysosome–autophagy system changes, particularly with respect to the role of lysophagy and the MT system, which point to some attractive targets for the design of engineered nanoparticles.
The electronic structure underlying electrocatalysis of two‐dimensional materials
Authors: Zhao Xunhua , Shi Jianjian , Ji Yujin , Liu Yuanyue
Published: May 2019

The understanding and development of advanced electrochemical catalysts have attracted intensive studies and achieved tremendous progress in the past decades. Two‐dimensional (2D) materials, such as doped graphene and atomically‐thin transition metal compounds, have shown great promise as electrocatalysts for various renewable energy conversion and storage reactions. Their further developments require improved understanding of the catalytic mechanisms at atomic level. Currently, most of the understandings are based on the formation free energies of the intermediates, which are determined by their binding strengths with the catalyst, usually calculated from density functional theory (DFT). These energies/binding strengths have been used as descriptor to describe the activity of many catalysts. However, it remains less explored why different catalysts have different binding strengths and what are the underlying factors controlling them, requiring studies going beyond atomic level to electronic level. This review aims to provide such links, focusing on 2D electrocatalysts for hydrogen evolution reaction (HER), oxygen reduction reaction/oxygen evolution reaction (ORR/OER), CO2 reduction reaction (CO2R) and nitrogen reduction reaction (NRR). We also discuss some of the significant issues that need to be addressed in DFT calculations, including the effects of varying charge and fixed potential of the catalyst, the passivation of active sites, and the solvation effects.

This article is categorized under:

Structure and Mechanism > Reaction Mechanisms and Catalysis

Structure and Mechanism > Computational Materials Science
Nanosized Functional MOFs Loading Ag/AgBr with Throughout‐Visible‐Light Absorption for High‐Efficiency Photocatalysis
Authors: Wang Jun‐Hao , Huang Sheng‐Zheng , Yang Shan‐Shan , Chen Yun‐Long , Wu Ya‐Meng , Li Na‐Na , Dong Xi‐Yan , Li Fei‐Fei
Published: May 2019

Porous metal‐organic frameworks (MOFs) loading metal nanoparticles to form a composite photocatalyst demonstrated unique advantages. Modification of the electron donating group on the aromatic linkers of MOFs could increase the absorption range of light, thereby increasing the photocatalytic activity. In this study, we prepared a composite photocatalyst using a stable NH2‐functionalized MOF (UiO‐66‐NH2) to load semiconductor Ag/AgBr nanoparticles, and the resultant composites have intense optical absorption throughout visible light range. The greatly enhanced optical absorption and the unique hetero‐junction between Ag/AgBr and UiO‐66‐NH2 render efficient separation and utilization of photogenerated electron‐hole pairs. Therefore, Ag/AgBr@UiO‐66‐NH2 showed much more excellent photocatalytic activity, compared with unmodified UiO‐66 loading Ag/AgBr (Ag/AgBr@UiO‐66) and reported AgX@MOF catalysts. Moreover, the composite photocatalysts showed excellent stability during cycling experiment.
The singular limits of Riemann solutions to a chemotaxis model with flux perturbation
Authors: Shen Chun , Sun Meina
Published: May 2019

The phenomenon of chemotactic collapse is identified and analyzed for a chemotaxis model in a conservative form when the diffusion effect is neglected by using a singular perturbation of flux function. It is proven rigorously that the Riemann solutions for the scaled chemotaxis system converge to the corresponding ones for a non‐strictly hyperbolic system of conservation laws when the scaled parameter tends to zero. In addition, in some particular situations, the delta standing wave is obtained in the limit situation, which can be used to explain reasonably the phenomenon of chemotactic collapse.
Instabilities of thin black rings: closing the gap
Authors: Armas Jay , Parisini Enrico
Published: May 2019

Abstract

We initiate the study of dynamical instabilities of higher-dimensional black holes using the blackfold approach, focusing on asymptotically flat boosted black strings and singly-spinning black rings in D ≥ 5. We derive novel analytic expressions for the growth rate of the Gregory-Laflamme instability for boosted black strings and its onset for arbitrary boost parameter. In the case of black rings, we study their stability properties in the region of parameter space that has so far remained inaccessible to numerical approaches. In particular, we show that very thin (ultraspinning) black rings exhibit a Gregory-Laflamme instability, giving strong evidence that black rings are unstable in the entire range of parameter space. For very thin rings, we show that the growth rate of the instability increases with increasing non-axisymmetric mode m while for thicker rings, there is competition between the different modes. However, up to second order in the blackfold approximation, we do not observe an elastic instability, in particular for large modes m ≫ 1, where this approximation has higher accuracy. This suggests that the Gregory-Laflamme instability is the dominant instability for very thin black rings. Additionally, we find a long-lived mode that describes a wiggly time-dependent deformation of a black ring. We comment on disagreements between our results and corresponding ones obtained from a large D analysis of black ring instabilities.
Moduli space of paired punctures, cyclohedra and particle pairs on a circle
Authors: Li Zhenjie , Zhang Chi
Published: May 2019

Abstract

In this paper, we study a new moduli space

$$ {\mathrm{\mathcal{M}}}_{n+1}^{\mathrm{c}} $$

ℳ

n
+
1

c

, which is obtained from

$$ {\mathrm{\mathcal{M}}}_{0,2n+2} $$

ℳ

0
,
2
n
+
2

by identifying pairs of punctures. We find that this space is tiled by 2
n − 1
n! cyclohedra, and construct the canonical form for each chamber. We also find the corresponding Koba-Nielsen factor can be viewed as the potential of the system of n+1 pairs of particles on a circle, which is similar to the original case of

$$ {\mathrm{\mathcal{M}}}_{0,n} $$

ℳ

0
,
n

where the system is n−3 particles on a line. We investigate the intersection numbers of chambers equipped with Koba-Nielsen factors. Then we construct cyclohedra in kinematic space and show that the scattering equations serve as a map between the interior of worldsheet cyclohedron and kinematic cyclohedron. Finally, we briefly discuss string-like integrals over such moduli space.
Uncertainty quantification of unsteady source flows in heterogeneous porous media
Authors: Severino Gerardo , Leveque Santolo , Toraldo Gerardo
Published: May 2019

Unsteady flow generated by a point-like source takes place into a$d$-dimensional porous formation where the spatial variability of the hydraulic conductivity$K$is modelled within a stochastic framework that regards$K$as a stationary, normally distributed random space function (rsf). As a consequence, the hydraulic head$H$becomes also stochastic, and we aim at quantifying its uncertainty. Towards this aim, we have derived the head covariance by means of a perturbation expansion which regards the variance$\unicode[STIX]{x1D70E}^{2}$of the zero meanrsf$\unicode[STIX]{x1D700}=1-K/\langle K\rangle$(hereafter$\langle \rangle$being the ensemble average operator) as a small parameter. The analytical results are expressed in terms of multiple quadratures which are markedly reduced after adopting specific autocorrelation$\unicode[STIX]{x1D70C}$for$\unicode[STIX]{x1D700}$. This enables one to obtain simple results providing straightforward physical insight into the spatial distribution of$H$as a consequence of the heterogeneity of$K$. In view of those applications (pumping tests) aiming at the identification of the hydraulic properties of geological formations, we have focused on a flow generated by a source of instantaneous and constant strength. The attainment of the large time (steady-state) regime is studied in detail.
Towards a finite-time singularity of the Navier–Stokes equations. Part 2. Vortex reconnection and singularity evasion
Authors: Moffatt H. K. , Kimura Yoshifumi
Published: May 2019

In Part 1 of this work, we have derived a dynamical system describing the approach to a finite-time singularity of the Navier–Stokes equations. We now supplement this system with an equation describing the process of vortex reconnection at the apex of a pyramid, neglecting core deformation during the reconnection process. On this basis, we compute the maximum vorticity $\unicode[STIX]{x1D714}_{max}$ as a function of vortex Reynolds number $R_{\unicode[STIX]{x1D6E4}}$ in the range $2000\leqslant R_{\unicode[STIX]{x1D6E4}}\leqslant 3400$, and deduce a compatible behaviour $\unicode[STIX]{x1D714}_{max}\sim \unicode[STIX]{x1D714}_{0}\exp [1+220(\log [R_{\unicode[STIX]{x1D6E4}}/2000])^{2}]$ as $R_{\unicode[STIX]{x1D6E4}}\rightarrow \infty$. This may be described as a physical (although not strictly mathematical) singularity, for all $R_{\unicode[STIX]{x1D6E4}}\gtrsim 4000$.
Existence and uniqueness of monotone wavefronts in a nonlocal resource-limited model
Authors: Trofimchuk Elena , Pinto Manuel , Trofimchuk Sergei
Published: May 2019

We are revisiting the topic of travelling fronts for the food-limited (FL) model with spatio-temporal nonlocal reaction. These solutions are crucial for understanding the whole model dynamics. Firstly, we prove the existence of monotone wavefronts. In difference with all previous results formulated in terms of ‘sufficiently small parameters’, our existence theorem indicates a reasonably broad and explicit range of the model key parameters allowing the existence of monotone waves. Secondly, numerical simulations realized on the base of our analysis show appearance of non-oscillating and non-monotone travelling fronts in the FL model. These waves were never observed before. Finally, invoking a new approach developed recently by Solar et al., we prove the uniqueness (for a fixed propagation speed, up to translation) of each monotone front.
An 18 ka to present pollen- and phytolith-based vegetation reconstruction from Hall's Cave, south-central Texas, USA
Authors: Cordova Carlos E. , Johnson William C.
Published: May 2019

Pollen, spores, phytoliths, and microscopic charcoal from a sedimentary column in Hall's Cave, south-central Texas, provide information for local and regional vegetation change during the last deglaciation and the Holocene in the context of broader regional and global climatic changes. The combination of paleoenvironmental proxy data from the cave indicates that between about 18,000 and 16,500 cal yr BP the cave area was dominated by an open plant community consisting of herbaceous vegetation, dominated by C3grasses, and scattered trees, primarilyQuercusandPinusspecies. After about 16,500 cal yr BP, the arboreal component fluctuated, attaining a peak between 14,000 and 13,000 cal yr BP with relatively equal proportions of C3and C4grasses, including a sizable proportion of Panicoideae grasses. The Younger Dryas is marked by a conspicuous decrease in arboreal pollen with an apparent increase of C4grasses toward its termination. Early Holocene recovery of arboreal vegetation is followed by a drying trend marked by the increasing dominance of C4drought-tolerant Chloridoideae grasses. Increasing human use of the cave in middle to late Holocene times creates noise in the climatic significance of pollen, phytolith, and other proxies, a factor to consider when interpreting paleoenvironmental proxies in other cave sedimentary records.
A Developmental Model of Heterogeneous Economic Voting in New Democracies
Authors: Duch Raymond M.
Published: May 2019

I argue that information and trust in nascent democratic institutions are two important sources of heterogeneity in economic voting in transition democracies. Economic voting develops in postcommunist electorates as ambiguity regarding the link between government policy and economic outcomes declines. The link becomes less ambiguous as citizens become more informed about how democratic institutions function and gain increasing confidence or trust in the responsiveness of these institutions to public preferences. In the early period of democratization the conditions necessary for an effective agency relationship between voter and incumbent are not yet fully developed. Economic voting increases as these levels of information on, and trust in, government rise. The analysis that tests these propositions is based on a public opinion survey conducted in Hungary in 1997. The test is replicated with a 1997 Polish election survey.
Peacemaking in Rwanda: The Dynamics of Failure. By Bruce D. Jones. Boulder, CO: Lynne Rienner, 2001. 200p. $49.95.
Authors: Walter Barbara F.
Published: May 2019

By almost all indicators, Rwanda's civil war should have ended in a successful negotiated settlement. Both the Tutsi rebels and the Rwandan government had agreed to participate in negotiations brokered by a team of Tanzanian mediators whom most people considered highly skilled. The two parties to the negotiations were able to reach and sign a detailed peace settlement that guaranteed both parties representation in the legislature and a set percentage of slots in the military. And the United Nations offered to “guarantee” the security of the two sides during the implementation period. Almost all factors purported to lead to a peaceful solution were present at the time the Arusha accords were signed in 1994. Rwanda's civil war, however, did not end peacefully. Instead, a peace process that seemingly had all the elements of success ended in one of the most rapid genocides in recorded history.
Reinventing Khomeini: The Struggle for Reform in Iran. By Daniel Brumberg. Chicago: University of Chicago Press, 2001. 306p. $55.00 cloth, $21.00 paper.
Authors: Boroujerdi Mehrzad
Published: May 2019

This is a book about a man who may be considered “the twentieth century's last example of a ‘pure’ charismatic leader” (p. 5). With these words, Daniel Brumberg begins to analyze the thoughts and legacy of Ayatollah Ruhollah Khomeini (1902–89), who came to power in Iran in February 1979. In his introduction, the author maintains that his study provides “an accurate, objective, yet sociologically empathetic evaluation of the very complex process of ideological change in the Islamic Republic of Iran” (p. 8).
The Breakdown of Class Politics: A Debate on Post-Industrial Stratification. Edited by Terry Nichols Clark and Seymour Martin Lipset. Baltimore: Johns Hopkins University Press, 2001. 352 p. $18.95.
Authors: Klausen Jytte
Published: May 2019

This book is a collection of essays from a 1996 conference that brought together a number of political sociologists to discuss an article from 1991 by the coorganizers, Terry Nichols Clark and Seymour Martin Lipset, originally published in International Sociology. They argued that the collapse of blue-collar industries and other changes in occupational and income structures associated with postindustrial social stratification had lead to a breakdown of class politics. Two years later, the journal published a rebuttal by Mike Hout, Clem Brooks, and Jeff Manza that class conflict remained important but that the political parties ignored it. The two articles and a 1993 response by Clark and Lipset are republished here together with a series of response papers written for the 1996 conference. Hout et al. criticized Clark and Lipset for failing to distinguish between class as a social phenomenon and the political representation of class. “Class interests may remain latent in the political arena,” they wrote, “but this does not mean that they do not exist” (p. 64).
Geophysical investigation across the Peel boundary fault (The Netherlands) for a paleoseismological study
Authors: Demanet D. , Evers L.G. , Teerlynck H. , Dost B. , Jongmans D.
Published: May 2019

In preparation of the first paleoseismic trenching in the NE border of the Roer graben (the Netherlands), site selection was carried out. Combining geological and seismological information and using existing aerial photographs, seismic reflection and geodetic levelling data, it was decided to focus on the Peel boundary fault near the village of Neer. Detailed information on the exact location of the fault was obtained through geophysical techniques, mainly ground penetrating radar (GPR) and resistivity measurements. GPR data unambiguously showed the flexuring and offset of reflectors affected by the fault. Performing eleven GPR profiles along strike allowed to obtain a 3D picture of the fault, laterally extending the information given in the trench.
Paleoseismological Investigations at the Rurrand Fault, Lower Rhine Embayment
Authors: Lehmann K. , Klostermann J. , Pelzing R.
Published: May 2019

From 1998 to 2000, we have studied the evidence for large paleoearthquakes at the Rurrand Fault. This fault represents the eastern border of the Roer Valley Graben, which is the tectonically most active region in the Lower Rhine Embayment. The purpose of our paleoseismological studies is to enlarge the seismicity data base for this region beyond instrumental records and historical reports using indications of surface-faulting events from stratigraphie conditions at active faults. Larger time spans considered in the earthquake catalogue will enable a more reliable statistical analysis which is required for seismic hazard assessment. Based on analyses of geological data and géomorphologie investigations, detailed geophysical surveying was carried out along the southern Rurrand Fault segment for the selection of a site appropriate to paleoseismological studies. Mapping of physical parameter contrasts with seismic reflection, VES, ERT, and GPR measurements along fault-crossing profiles inferred position and near-surface structure of the fault. At the site promising the best conditions, a trench was excavated across the fault near the city of Jiilich, Germany. Within a depth of about 4 m, the Rurrand Fault was exposed in an about 50 m-wide system of faults and fault zones, affecting the stratigraphie sequence with various displacement characteristics and amounts of throw. According to heavy mineral analyses, the deposition time of most the exposed sediment strata was assigned to Pliocene and Lower Pleistocene time. These geological units are covered by loess layers deposited through so-lifluction processes during the Weichselian glacial, i.e. some tens of ka B.P., or – with lower probability – during the Saalian glacial. Several faults which had also affected the loess reflect younger fault activity. However, clear paleoseismic features were not observed in the trench, thus an unambiguous proof of the occurrence of coseismic fault displacements could not be furnished. Recently, differential subsidence due to drainage takes place in the surroundings of the nearby opencast mining. An amount of some 0.35 m, concentrated in a very narrow lateral zone, has been observed during the last 40 a at about 1 km distance from the trench position. To date, the subsidence could not be clearly located in the trench exposure. Results from geodetic levelling campaigns will help to determine the offset residuals and to gain better insight into the ruling displacement processes at the Rurrand Fault.
THE USE OF INDUCED ABORTION AS A CONTRACEPTIVE: THE CASE OF MONGOLIA
Authors: PANDEY R. N.
Published: May 2019

After the onset of liberlization of the Mongolian economy in 1989, the laws governing abortion were relaxed. Furthermore, the availability and use of modern contraceptives also started to improve. The Demographic Survey of Mongolia, conducted during June–July 1996, collected information on different aspects of abortion. This paper presents the results on the prevalence of induced abortion and other related issues. It was found that in the absence of adequate knowledge and availability of modern contraceptives in Mongolia, the prevalence of induced abortion was relatively high. About 24% of women undergoing abortion were using it as a contraceptive because they thought it to be a safe method of contraception. Though the abortion rules stipulate counselling on the use of modern contraceptives just after an abortion, only 60% of women undergoing an abortion were given such counselling.
The Movement of Ideas in Late Iron Age and Early Roman Britain: An Imported Rotary Quern Design in South-Western England
Authors: Shaffrey Ruth
Published: May 2019

In 2012, a complete upper stone of a rotary quern with a projecting lug for a vertical handle was found at Hinkley Point in Somerset, south-western England. It is the first late Iron Age to early Roman period quern of this form to be found in England. This note describes its form in detail and discusses its closest parallels in north-eastern Ireland, south-western Scotland, Wales, Isle of Man and Spain. It shows how thin-section analysis demonstrates the quern to have been locally made in Somerset and discusses the movement of ideas about quern design during the late Iron Age to early Roman period.
A common framework for perception and action: Neuroimaging evidence
Authors: Chaminade Thierry , Decety Jean
Published: May 2019

In recent years, neurophysiological evidence has accumulated in favor of a common coding between perception and execution of action. We review findings from recent neuroimaging experiments in the action domain with three complementary perspectives: perception of action, covert action triggered by perception, and reproduction of perceived action (imitation). All studies point to the parietal cortex as a key region for body movement representation, both observed and performed.
Visual conscious perception could be grounded in a nonconscious sensorimotor domain
Authors: Ansorge Ulrich , Scharlau Ingrid , Heumann Manfred , Klotz Werner
Published: May 2019

Visual conscious perception could be grounded in a nonconscious sensorimotor domain. Although invisible, information can be processed up to the level of response activation. Moreover, these nonconscious processes are modified by actual intentions. This notion bridges a gap in the theoretical framework of O'Regan & Noë.
Cantor coding and chaotic itinerancy: Relevance for episodic memory, amnesia, and the hippocampus?
Authors: Foster Jonathan K.
Published: May 2019

This commentary provides a critique of Tsuda's target article, focusing on the hippocampus and episodic long-term memory. More specifically, the relevance of Cantor coding and chaotic itinerancy for long-term memory functioning is considered, given what we know about the involvement of the hippocampus in the mediation of long-term episodic memory (based on empirical neuroimaging studies and investigations of brain-damaged amnesic patients).
Control of chaos and memory dynamics
Authors: Heath Richard A.
Published: May 2019

Neurally inspired models of human cognition exude explanatory power without necessarily making predictions that can be verified behaviorally. This is the case for Tsuda's dynamic model. It is suggested that a simpler principle based on the nonlinear dynamic interaction between modules based on control of chaos, can achieve a similar theoretical goal in a cognitively verifiable way.
Theory of event coding: Interesting, but underspecified
Authors: Oriet Chris , Stevanovski Biljana , Jolicoeur Pierre
Published: May 2019

The Theory of Event Coding (TEC) is a new framework for understanding interactions between perception and action. We are concerned that the theory is underspecified, showing that it can easily be used to make exactly opposite predictions. Precise specification of the time course of activation and binding is needed to make the theory useful for understanding the perception-action interface.
The plausibility of a chaotic brain theory
Authors: Tsuda Ichiro
Published: May 2019

We consider the significance of high-dimensional transitory dynamics in the brain and mind. In particular, we highlight the roles of high-dimensional chaotic dynamical systems as an “adequate language” (Gelfand 1989), which should possess both explanatory and predictive power of description. We discuss the methods of description of dynamic behavior of the brain. These methods have been adopted to capture the averaged or deterministic complexity, and further to allow for discussion of a new approach to capture the complexity of the deviation from such an averaged complexity and also the complexity of interactive modes. We also give arguments in defense of our models for dynamic memory with chaotic itinerancy and Cantor coding. In addition, we discuss the reality that a model of the brain and mind should reflect.
How specific and common is common coding?
Authors: Sanders Andries F.
Published: May 2019

This commentary addresses three points. First, it is argued that the common coding principles, as developed in the target article, may supplement rather than replace stage views of human information processing. Second, the issue of the properties of an event code is briefly discussed. It is concluded that much remains to be specified so as to allow critical tests. Finally, the question of the limits of common coding is raised. It may be particularly relevant to direct perception and action coupling but less useful for the analysis of cognitive skills.
Reexamining visual cognition in human infants: On the necessity of representation
Authors: Schlesinger Matthew
Published: May 2019

The sensorimotor account of vision proposed by O'Regan & Noë (O&N) challenges the classical view of visual cognition as a process of mentally representing the world. Many infant cognition researchers would probably disagree. I describe the surprising ability of young infants to represent and reason about the physical world, and ask how this capacity can be explained in non-representational terms. As a first step toward answering this question, I suggest that recent models of embodied cognition may help illustrate a way of escaping the representational trap.
Two Marathi Letters from the Arsip Nasional Republik Indonesia: A Snapshot of Dutch-Maratha Relations in the Late-Eighteenth-Century Coromandel
Authors: Bellarykar Nikhil
Published: May 2019

The third volume of Dutch Sources on South Asia mentions that there are some late-eighteenth-century Marathi letters, written in the Modi script, preserved in the National Archives of the Republic of Indonesia.1 Scanned copies of the same were obtained by Lennart Bes (Leiden University) with the kind permission of the Indonesia Archives. Using these scanned copies, this paper gives the complete Roman transliteration of the two letters as well as their translation, and contextualizes the letters within Maratha documentary practices as well as within the contemporary political scene of the late-eighteenth-century Coromandel Coast. In addition, this article provides a commentary on the Maratha perception of Europeans in general and of the Dutch in particular, arguing that the Marathas had an unusually positive opinion about the trade-oriented Dutch, especially when contrasted with the territorially ambitious English and the Portuguese.
Presence and Chromosomal Subtyping ofLegionellaSpecies in Potable Water Systems in 20 Hospitals of Catalonia, Spain
Authors: Sabrià Miquel , García-Núñez Marian , Pedro-Botet Maria L. , Sopena Nieves , Gimeno Josep M. , Reynaga Esteban , Morera Josep , Rey-Joly Celestino
Published: May 2019

Objective:

To investigate the presence and clonal distribution ofLegionellaspecies in the water supply of 20 hospitals in Catalonia, Spain.

Setting:

20 hospitals in Catalonia, an area of 32,000 km2, located in northeast Spain.

Methods:

Environmental cultures of 186 points of potable water supply and 10 cooling towers were performed for the presence ofLegionellaspecies. Following filtration and acid treatment, the samples were seeded in selective MWY (modified Wadowsky Yee)-buffered charcoal yeast extract-a agar. All isolates obtained were characterized microbiologically and genotyped bySfilpulsed-field gel electrophoresis (PFGE).

Results:

73 of 196 water samples, representing 17 of the 20 hospitals included in the study, were positive forLegionella pneumophila(serogroups 1, 2-14, or both). The degree of contamination ranged from 200 to 74,250 colony-forming units/L. Twenty-five chromosomal DNA subtypes were detected by PFGE. A single DNA subtype was identified in 10 hospitals, 2 DNA subtypes were observed in 6 hospitals, and 1 hospital exhibited 3 different DNA subtypes. Each hospital had its ownLegionellaDNA subtype, which was not shared with any other hospitals.

Conclusions:

Legionellawas present in the water of most of the hospitals studied; each such hospital had a unique, dominant chromosomal DNA subtype. The verification of several genomic DNA restriction profiles in such a small geographic area demonstrates the great genetic diversity ofLegionellain the aquatic environment.
Outbreak of Nosocomial Sepsis and Pneumonia in a Newborn Intensive Care Unit by Multiresistant Extended-Spectrum β-Lactamase-ProducingKlebsiella pneumoniaeHigh Impact on Mortality
Authors: Martínez-Aguilar Gerardo , Alpuche-Aranda Celia M. , Anaya Carmen , Alcantar-Curiel Dolores , Gayosso Catalina , Daza Carlos , Mijares Cesar , Tinoco Juan C. , Santos Jose I.
Published: May 2019

We describe a case-control study of a small outbreak of nosocomial sepsis and pneumonia with high mortality due to clonal dissemination of a multiresistantKlebsiella pneumoniaein the neonatal intensive care unit of a Mexican institution. Our study helped to change nosocomial infection control policy in this hospital.
The effects of two contrasting grassland-based milk production systems, on the performance and fertility of high genetic merit, autumn calving, dairy cows
Authors: Ferris C.P. , McCoy M.A. , Lennox S.D. , Catney D.C. , Gordon F.J.
Published: May 2019

The development of production systems, which allow increased nutrient intakes to be achieved, is a key issue in the management of high genetic merit dairy cows. Consequently, forty high genetic merit autumn calving dairy cows (PTA95fat + protein = 38.2 kg) were managed on either a ‘high forage (HF)’ or ‘high concentrate (HC)’ based system of milk production for the first 305 days of lactation, with the study encompassing both the indoor winter and outdoor summer grazing periods. System HF involved a high feed value silage, a lax grazing regime, and a low concentrate input (842 kg DM), while system HC involved a medium feed value silage, a tighter grazing regime and a higher concentrate input (2456 kg DM). Total milk outputs with each of systems HF and HC were 7854 and 8640 kg respectively (P<0.01), illustrating that high genetic merit cows can perform satisfactorily on very different inputs over a single lactation. However animals on system HF experienced a more extreme and prolonged period of negative energy balance post partum than those on system HC, and completed the winter with a significantly lower condition score. Detailed fertility records were maintained for all animals on the study. Days to first observed heat were 51.2 and 59.3 with systems HF and HC respectively, while the respective conception rates to first service were 26 and 21%. The number of services/conception were 2.22 and 2.50, while the calving interval was 390 and 404 days for systems HF and HC respectively. Despite the greater degree of negative energy balance associated with system HF, none of the fertility measures was significantly affected by system of milk production (P>0.05), although fertility with both systems was poor. There were no obvious reasons for the poor fertility noted in this trial.
Respective frequencies of early and late embryonic mortality in Prim’ Holstein cows under subtropical conditions
Authors: Tillard E. , Nabeneza S. , Faye B. , Humblot P.
Published: May 2019

The frequency of early and late embryonic mortality was determined following 171 inseminations performed between January and December 1998 in 6 herds located in Reunion Island. Milk was sampled 23 to 24 days after Alfor progesterone determination in cows not observed to return to oestrus after AI. Cows were also blood sampled at between 30 and 45 days post-AI to measure Pregnancy Specific Protein B. Overall pregnancy rate was 25.1% (range between herds 12.5% to 42.3%). Early embryonic mortality or fertilisation failures and late embryonic mortality occurred in 57.3% (range between herds 52.9% to 61.6%) and 17.5% (range between herds 3.8% to 33.4%) of cows inseminated, respectively. Nonpregnant cows, not detected in oestrus by Day 24 after AI were recorded to returned to oestrus, on average 66 ±9.6 days or more than 3 cycles after AI. The pregnancy rate was depressed when cows were inseminated during the wet season compared with cows inseminated during the dry season. We conclude that fertilisation failures or early embryonic mortality was the main cause of reproductive failure in inseminated cows in tropical climates. The incidence was twice that obtained in studies conducted under more temperate climatic conditions.
Evaluation of the Early Conception Factor (ECFtm) Test in Cows 3-7 Days Post-Breeding
Authors: Adams C. S. , Jardon P. W.
Published: May 2019

Reduction of the number of days open is economically desirable for the dairy producer. A test is currently being marketed which claims to accurately detect the open cow at 3-7 days post breeding via the detection of a unique protein detected in the serum of the pregnant cow. Evaluation of this test revealed a sensitivity of .51 and a specificity of .55. These results indicate that the test, as performed in this study, did not accurately assess the open status of dairy cattle.
The detection and treatment of post insemination progesterone insufficiency in dairy cows
Authors: Starbuck G R , Darwash A O , Mann G E , Lamming G E
Published: May 2019

An analysis on the outcome of 124 inseminations monitored using daily milk progesterone concentration data revealed that those cows in which pregnancy did not occur experienced a 1.7day delay in post-ovulatory luteal progesterone rise when compared to the pregnant group (P<0.001). This suggests that luteal progesterone secretion needs to be initiated prior to day 5 post-ovulation. A comparison between the milk progesterone concentration on day 5 post-ovulation and the pregnancy rate for 1451 inseminations showed the maximum pregnancy rate to occur when the milk progesterone concentration was between 3-9ng/ml. Pregnancy rate fell significantly (P<0.01) when progesterone concentrations were below 3ng/ml, identifying cows that may benefit from progesterone supplementation. The supplementation of progesterone in cows with a day 5 milk progesterone concentration of less than 3ng/ml, using an intra-vaginal progesterone releasing device, only provided benefit for those cows with a day 5 progesterone concentration of between 1-2ng/ml, resulting in a doubling of the pregnancy rate. This data shows that a delay in post-ovulatory progesterone secretion has a detrimental effect on pregnancy but that not all cows with a deficient progesterone concentration benefit from progesterone supplementation.
Effects of treatment with a gonadotrophin-releasing hormone analogue on follicle development in dairy cows fed one of two different diets
Authors: Bleach E.C.L. , Moore C.L. , Zeale H.J. , Knight P.G.
Published: May 2019

Follicle development occurs in two or three waves during the bovine oestrous cycle. Artificially extending the duration of ovulatory follicle dominance influences pregnancy rates in cattle, as does the interval from emergence to oestrus in dairy cows undergoing spontaneous oestrous cycles. The objectives of the presented study were to determine whether the interval from ovulatory follicle emergence to oestrus might be altered by diet and/or gonadotropin-releasing hormone (GnRH) treatment. Lactating primiparous Holstein/Friesian cows (n=21) were randomly allocated to one of two diets at calving (Diet 1, n=ll, DM 480 g/kg, metabolisable energy 12.0 MJ/kg DM crude protein 178 g/kg DM, oil B 48 g/kg DM, neutral detergent fibre 318 g/kg DM and diet 2, n=10, DM 440 g/kg, metabolisable energy 12.1 MJ/kg DM, crude protein 172 g/kg DM, oil B 40 g/kg DM, neutral detergent fibre 300 g/kg DM). From 10 days after observed oestrus (oestrus 1), ovarian follicular and luteal development was monitored by daily transrectal ultrasonography until the subsequent oestrus and ovulation. A GnRH analogue was injected (i.m.; 10 μg) 12 days after oestrus 1 in 6 cows fed diet 1 and 5 cows fed diet 2. Oestrous cycle length was longer (p<0.05) in control cows fed diet 1 than those fed diet 2. Treatment with GnRH increased (p<0.005) cycle length in cows fed diet 2 but not those fed diet 1. Increases in cycle length observed were associated with longer luteal phase length. Follicular phase length was reduced (p<0.05) by GnRH treatment in cows fed diet 1. Ovulatory follicles emerged later (p<0.05) in control cows fed diet 1 than those fed diet 2. GnRH treatment delayed (p<0.01) the emergence of the ovulatory follicle in cows fed diet 2, this delay was associated with an increase (p<0.05) in the incidence of 3 follicle waves in oestrous cycles following GnRH treatment. The interval from emergence of the ovulatory follicle to the subsequent oestrus was similar among the treatment groups. We conclude that treatment with GnRH during the mid-luteal phase may delay the emergence of the ovulatory follicle. However, the response is dependent on diet fed. Where ovulatory follicle emergence is delayed, the interval from emergence to the subsequent oestrus was unaffected since oestrous cycle length is extended.
Field assessment of GnRH-PGF2α oestrous synchronisation in confined Holstein cows
Authors: Cox J.F. , Saravia F. , Torrealba O. , Zavala A. , Lobos A.
Published: May 2019

The present study determined the effect of a GnRH and PGF2α treatment on proportion of cows detected in oestrus, the distribution of oestrous activity and subsequent fertility. The study also incorporated the use of ovarian ultrasound and milk progesterone assay to established a better overall assessment of treatments. Holstein-Friesian cows, averaging 9000-kg milk/lactation, and fed according to their requirements were used in the study. Cows were regularly cyclic; at least 60 days postpartum, had had two oestrous cycles and were clinically sound before being considered for either experiment. In Experiment 1, 274 cows were treated at random with an i.m. injection of 10 μg of GnRH (buserelin) followed 7 days later by 0.75 mg oftiaprost based on the ultrasound diagnosis of a corpus luteum. At that time and 3 days later, milk samples were collected and assayed for progesterone. Cows with progesterone concentrations >1 ng/ml were considered to have a corpus luteum, and luteolysis was assumed to have occurred when concentrations 3 days later were <0.8 ng/ml. In Experiment 2, 1431 cows were treated as above. The response to treatment was assessed by presence of a corpus luteum 7 d after GnRH treatment, oestrous detection rate, and distribution of heats and ultimately on conception rate. Conception rate was compared to untreated control cows inseminated by the same inseminator and using semen from the same sires. Artificial breeding was carried out after oestrous detection and pregnancy diagnosis was done by ultrasound. In Experiment 1, luteolysis was induced in 244/274 (89.1%) cows following PGF2α administration, with 198/214 (92.5%) been diagnosed correctly in heat and 16/214 (7.5%) been diagnosed in error based on progesterone profiles. Oestrous activity was most concentrated on day 3 (59.1%), with 20.7% and 16.7% of heats recorded on d 2 and d 4, respectively. When compared to untreated controls, GnRH-PGF2α treated cows had a better conception rate (56.6 vs. 39.5%, P<0.01). In Experiment 2, 1012/1431 (70.7%) had a CL 7 days after GnRH injection; 709/1012 (70.1%) cows were detected in oestrus, and 359/700 (51.3%) cows became pregnant after insemination compared to 182/434 (41.9%) of untreated controls (P<0.05). The utilisation of GnRH and PGF2α seems to be a useful synchronisation scheme based on AI after oestrous detection. However, variations in fertility after treatment demands a better understanding offactors affecting herd fertility under controlled schemes.
A criterion for elliptic curves with second lowest 2-power in L(1)
Authors: ZHAO CHUNLAI
Published: May 2019

Let D = p1 … pm, where
p1, …, pm are distinct rational primes ≡ 1(mod 8), and
m is any positive integer. In this paper, we give a simple combinatorial criterion
for the value of the Hecke L-function of the congruent elliptic curve
ED2 : y2
= x3 − D2x at s = 1, divided by the period ω
defined below, to be exactly divisible by 4m. As a corollary, we obtain a series of non-congruent
numbers whose number of prime factors tends to infinity, and for which the corresponding elliptic curves have
non-trivial 2-part of Tate–Shafarevich group, which greatly generalizes a result of
Razar [8]. Our result is in accord with the predictions of the conjecture of Birch and
Swinnerton-Dyer.
Dopamine activates ATP-sensitive K+ currents in
rat retinal pericytes
Authors: WU DAVID M. , KAWAMURA HAJIME , LI QING , PURO DONALD G.
Published: May 2019

The relatively sparse vasculature of the retina minimizes
obstruction to incoming light, but also poses a challenge to
fulfilling the metabolic demands of retinal neurons. An efficient
process for distributing energy supplies to areas of need is
likely to involve neuron-derived vasoactive signals. However,
knowledge of the mechanisms by which capillary perfusion is
regulated by neuron-to-vascular signaling is limited. Potential
targets of vasoactive molecules released from nerve cells are
the pericytes, which are positioned on the endothelial walls
of microvessels and are thought to play a role in controlling
the microcirculation. In this study, we assessed the effect
of dopamine on pericyte physiology. Because dopaminergic neurites
are closely associated with microvessels that express dopamine
receptors, this molecule is a putative neuron-to-capillary signal,
as well as neurotransmitter. We used the perforated-patch
configuration of the patch-clamp technique to monitor the
whole-cell currents of pericytes located on microvessels freshly
isolated from the adult rat retina. In 43% (58/134) of the sampled
pericytes, we found that dopamine reversibly activated a
hyperpolarizing current, which increased the membrane potential
by 19 ± 1 mV. This dopamine-induced current was inhibited
by the ATP-sensitive potassium (KATP) channel blocker,
glibenclamide. Consistent with a signaling pathway involving
D1 dopamine receptors, adenylate cyclase and protein
kinase A (PKA), the selective D1 antagonist, SCH23390,
inhibited the hyperpolarizing effect of dopamine; the activator
of adenylate cyclase, forskolin, mimicked the dopaminergic effect,
and H89, which inhibits PKA, significantly reduced the
hyperpolarization induced by dopamine. Taken together, our
experiments indicate that a mechanism involving D1
dopamine receptors, adenylate cyclase, and PKA activates
KATP currents in retinal pericytes. Our observations
support the hypothesis that, in addition to being a neuromodulator,
dopamine also serves as a signal linking neuronal activity with
the function of the pericyte-containing microvasculature.