bluuebunny/crossref_metadata_2025 huggingface dataset:
Potential Biological Control Agents for Goosegrass (Eleusine indica)
Authors: Figliola Suzanne S. , Camper N. D. , Ridings W. H.
Published: May 2019

Two leaf-spotting pathogens, [Bipolaris setariae(Saw.)] and [Piricularia grisea(Cke.) Sacc.], were isolated from severely infected goosegrass plants. Pathogenicity tests conducted at 28 C showed that both fungi were 100% effective in infecting goosegrass when given a 72-h dew period. Dew period temperature and duration requirements were tested by inoculating 2-week-old plants with conidial suspensions of each fungus and incubating them in dew chambers (100% relative humidity). Disease index increased as dew period duration increased for both fungi and at all temperatures tested. Infection occurred at all temperatures with an optimum of 24 to 28 C forB. setariaeand 28 C forP. grisea. In host range tests, representative plants of the Fabaceae, Malvaceae, Poaceae, and Solanaceae were inoculated with suspensions of either 20 000 or 60 000 spores/ml of each fungus and placed in growth chambers at 28 C. Infection was limited to members of the Poaceae. Sorghum showed a hypersensitive response toB. setariae. Both cultivars of corn developed light symptoms in response to both fungi at 20 000 and 60 000 spores/ml.
CANDIDATURE FEMMINILI E SISTEMI ELETTORALI
Authors: Beckwith Karen
Published: May 2019

Introduzione

La debole presenza delle donne nelle assemblee legislative nazionali costituisce un aspetto sorprendente quanto permanente della vita politica delle democrazie occidentali. La presenza femminile in tali istituzioni non si avvicina nemmeno lontanamente alla proporzione delle donne nella popolazione e, inoltre, la percentuale di donne elette é inferiore nettamente a quella delle candidate all'elezione (Rule 1981; Norris 1985; Bagdanor 1984). Nella maggior parte delle assemblee legislative dei paesi occidentali meno del 10% dei membri della prima camera sono donne. Del sorprendente isomorfismo della sotto-rappresentazione delle donne (Darcy, Welch e Clark 1987, cap. 1) nei parlamenti nazionali sono state avanzate diverse spiegazioni: 1) che le donne sono socializzate in modo poco funzionale al tipo di competizione politica richiesto per accedere alle posizioni elettive a livello nazionale; 2) che gli elettori preferiscono le candidature maschili a quelle femminili per tali posizioni; 3) che i leaders partitici sono restii a candidare delle donne in quei seggi o circoscrizioni in cui il partito si aspetta di vincere; 4) che le donne non hanno sufficiente ambizione politica e non si fanno avanti per la candidatura; 5) che le donne non hanno adeguata esperienza politica per questo tipo di cariche; 6) che le donne sono prive di una rilevante esperienza occupazionale per accedere alle cariche pubbliche. Queste spiegazioni fanno riferimento principalmente a comportamenti ed attributi delle donne in quanto candidati potenziali ed a quelli della leadership partitica e degli elettori come elementi potenzialmente discriminatori verso la candidatura delle donne. Un altro gruppo di potenziali elementi esplicativi si concentra invece sul contesto elettorale e la sua capacitá di modellare i comportamenti politici e di creare o meno opportunitá politiche per l'accesso delle donne alle cariche pubbliche elettive. Questi comprendono: 1) la cultura politica rilevante per le opportunitá politiche delle donne, come, per esempio, quanto é recente il suffragio femminile; 2) il tipo di partiti nel sistema partitico; 3) il tipo di sistema partitico; 4) gli equilibri elettorali, reali opresuntitra i partiti politici; 5) il contributo, reale opresunto, dell'elettorato femminile al mantenimento o alla destabilizzazione degli equilibri elettorali; e 6) il tipo di sistema elettorale. Questi fattori condizionano le opinioni degli attori politici (leaders partitici, candidati potenziali e elettori) e pongono dei vincoli alle loro scelte politiche.
COMPARAZIONE E METODO COMPARATO
Authors: Sartori Giovanni
Published: May 2019

Introduzione

Sulla politica comparata e sul metodo che la sostiene scrivevo vent'anni fa (quasi). Ne scrivevo perché ne ero fautore. Ma l'esito, oggi, è stato di gran lunga inferiore alle aspettative. Come mai? è per via di una sopravvalutazione iniziale? O perché siamo andati inciampando nel corso del cammino? O per altre ragioni ancora? Rispondere a queste domande è come tirare un consuntivo. Dove stiamo? Dove ci conviene andare? è un dibattito da riaprire. Nel mio scritto, diciamo, originario, chiedevo nell'ordine 1) perché comparare, 2) cosa è comparabile, 3) come comparare. Gioverà ripetere le stesse domande nello stesso ordine.
GENERAZIONI E MUTAMENTO POLITICO IN ITALIA
Authors: Giovannini Paolo
Published: May 2019

Introduzione

Nel dibattito scientifico internazionale ricorre spesso una relazione, carica però di genericità e ambiguità, tra generazioni e cambiamento politico. La congiunzione tra i due termini ipotizza un rapporto di interconnessione di cui non è nota la natura (si tratta di relazione causale?) né la direzione (quale è la causa, e quale l'effetto?) né le condizioni del suo verificarsi (c'è sempre una relazione, o essa si attiva solo in determinate contingenze storiche?). Senza voler affrontare una discussione sistematica in merito, vorrei però avanzare alcune riflessioni piò specificamente riferite al modo in cui intendo trattare il tema in questione.
VIDEOPOLITICA
Authors: Sartori Giovanni
Published: May 2019

Introduzione

La televisione sta cambiando l'uomo e sta cambiando la politica. Il mio tema é, qui, il potere politico della televisione, e quindi la video-politica; ma la video-politica è soltanto uno spicchio di un più generale video-potere che è il potere dell'immagine. Pertanto la video-politica trasforma la politica nel più alto contesto di un video-potere che sta trasformando in «uomo vedente» l'homo sapiens prodotto dalla cultura scritta. I due temi si intrecciano, e l'uno fluisce inevitabilmente nell'altro.
DECISIONI DI GOVERNO E VINCOLI PARTITICI
Authors: Blondel Jean
Published: May 2019

Introduzione

Fino ad ora, il dibattito sulla natura del processo decisionale interno ai gabinetti di governo è risultato inconcludente. Si è affermato con forza che, almeno in alcuni paesi, i primi ministri sono divenuti l'elemento dominante del processo decisionale e che la collegialità all'interno del gabinetto è ormai un mito; ma l'evidenza portata a sostegno di questa tesi è, nel migliore dei casi alquanto selettiva. Di fatto, presentare il problema in questi termini costituisce una grossa semplificazione poichè numerosi fattori interagiscono: il processo decisionale di gabinetto dipende da variabili come le personalità, il livello relativo di informazione dei ministri, la durata della loro permanenza nel gabinetto, i vincoli delle coalizioni ed anche le tradizioni culturali. Quindi, un approccio realistico a questo problema richiede che si proceda con cautela verso le conclusioni, raccogliendo materiale sulla enorme varietà di situazioni esistenti, classificandole e cercando di valutare l'influenza relativa delle diverse variabili.
DUE VIE ALLA CITTADINANZA: IL MODELLO SOCIETARIO E IL MODELLO STATALISTA
Authors: Zincone Giovanna
Published: May 2019

Introduzione

Quando vogliamo classificare i sistemi politici democratici e li osserviamo in un ottica comparata, tendiamo spesso a sottovalutare quei tratti che più specificamente determinano condizioni di vita diverse per i loro cittadini. Guardiamo, ad esempio, più spesso alla configurazione degli organi decisionali, ai modelli di competizione e di alleanza tra le élites; mentre ci capita meno spesso di utilizzare come criterio di classificazione la possibilità, che può avere un individuo qualunque, di influenzare le decisioni pubbliche. Anche le ricerche sulla partecipazione, che dovrebbero studiare la politica dal punto di vista dei governati, osservano di solito i comportamenti di fatto e le variabili socioeconomiche di tali comportamenti, mentre trascurano i caratteri del sistema. E anche quando se ne occupano, individuano le condizioni giuridiche che permettono o incentivano gli atti di partecipazione (quali ad esempio l'estensione del suffragio, da una parte, o il voto obbligatorio dall'altra), ma non si preoccupano di quei profili delle istituzioni che rendono tali atti di partecipazione efficaci (ad esempio, il ruolo più o meno cruciale degli organismi elettivi rispetto ad altre arene decisionali).
The Value of Carotid Doppler Ultrasound in Asymptomatic Extracranial Arterial Disease
Authors: Bornstein Natan M. , Chadwick Lorraine G. , Norris John W.
Published: May 2019

Carotid Doppler is an accurate, safe and repeatable method of assessing arterial calibre, for distinguishing harmless neck bruits and to identify the stroke prone individual. It is completely non-invasive and can be used serially to monitor progression in carotid stenosis. It is a valuable clinical tool in diagnosis and management in patients at risk of stroke, but has definite limitations, such as in differentiating carotid occlusion from severe stenosis. B-mode imaging, although valuable in identifying arterial anatomy, and detecting plaques, cannot accurately evaluate the degree of stenosis. It is of limited value in identifying plaque hemorrhage and ulceration. Doppler ultrasound technology has advanced rapidly in the last decade, especially in the combination of B-mode imaging and Doppler (Duplex), as well as in evaluating of the intracranial circulation (transcranial Doppler). In the next decade, it may become the new gold standard for evaluating the extracranial and intracranial circulation.
Status Epilepticus in Children
Authors: Yager J.Y. , Cheang M. , Seshia S.S.
Published: May 2019

We have prospectively reviewed the data on 52 children who presented with status epilepticus. Thirtyfour (65%) of the 52 had not had seizures before. Children who were previously abnormal were more likely to present with partial status epilepticus or to have seizures > 60 minutes than those who were previously normal. The median age (24 months) of those who presented with status epilepticus was the same as that of children with seizures of shorter duration. The causes were equally distributed among the idiopathic, acute encephalopathic and chronic encephalopathy groups. Three children died and 13 (28%) were left with neurological sequelae. The outcome was favorable for those in the idiopathic category.
Clobazam for Refractory Childhood Seizure Disorders - A Valuable Supplementary Drug
Authors: Munn Robert , Camfield Peter , Camfield Carol , Dooley Joseph
Published: May 2019

Clobazam is a new benzodiazepine recently introduced in Canada on an experimental basis. We report our experience with 27 children (average age 9.1 years) with severe intractable seizure disorders. All had mixed seizures (41% focal plus generalized, 59% mixed generalized) and 93% were mentally retarded. Eighty-five percent had multiple daily seizures and all had been on an average of 6 other anticonvulsants in the past. Forty-one percent of our patients responded to clobazam with a reduction of greater than 75% in seizure frequency and 15% had no further seizures. Tolerance to clobazam which could not be overcome by dose increases developed in 26% of patients. Fortyfour percent of non-responders had exacerbations of their seizures shortly after starting clobazam, however 43% of these patients had reductions in comedications simultaneously. Side effects of clobazam in responders were minimal. We conclude that clobazam shows sufficient promise to warrant further trials in more benign seizure disorders in children.
Primary Spontaneous Mesencephalic Hemorrhage
Authors: Mehler Mark F. , Ragone Philip S.
Published: May 2019

The case histories of two patients with clinically diverse forms of the very rare entity primary, spontaneous mesencephalic hemorrhage are presented. Each exhibited characteristic mesencephalic signs and neuroimaging profiles. However, both patients differed markedly in their predisposing factors, state of arousal, memory, temporal course and functional residua. One patient was unique in displaying a normal level of alertness throughout his clinical course and an isolated retrograde amnesia. The latter sign suggests a role for mesencephalic reticular activation in long-term retrieval and illustrates the differential effects of a subtle activation deficit on memory and arousal. These findings broaden the distinctive clinico-anatomical profile of primary, spontaneous mesencephalic hemorrhage.
Nonrobustness of Dynamic Dual Models of the Northeastern and U.S. Dairy Industries
Authors: Weersink Alfons
Published: May 2019

The robustness of dynamic dual models examined by Howard and Shumway is reevaluated with the proper specification for the modified generalized Leontief (GL) and normalized quadratic (NQ) functional forms. In an application to the Northeastern and U.S. dairy industries, the theoretical properties, adjustment rates, and predictive ability were similar under both functional forms. However, elasticity measures differed significantly.
Changing Conditions and Emerging Issues for Agriculture Production in the Northeast
Authors: White Gerald B.
Published: May 2019

Production agriculture in the Northeast represents a declining share of national agricultural production. Some of the characteristics of Northeast agriculture that affect its future are (1) an unfavorable resource base; (2) proximity to population centers; and (3) a diversity of enterprises. Major issues affecting the future include changing technology, changing structure, competitive advantage, regulation, and labor supply and demand. The role of specialty crops in Northeast agriculture was examined. Pesticide regulation and the labor requirement for specialty crops are serious constraints to widespread adoption.
Consumer Welfare Measures: Some Comparative Results
Authors: Heien Dale
Published: May 2019

Consumer's surplus has played an important role in evaluating agricultural price support programs as well as in other applications. Gardner and Wallace provide examples of the use of consumer's surplus in theoretical models, while numerous empirical studies (for example, Anderson, Sedjo and Wiseman, Johnson and Norton) have used the concept to measure welfare costs. Since its introduction by Dupuit and Marshall, the interpretation of consumer's surplus has been subject to change and controversy. In an important paper, Willig demonstrated that consumer's surplus is bounded by compensating variation (C) and equivalent variation (E) and derived rules of thumb showing how closely consumer's surplus approximates these appropriate welfare measures. These rules are compact and readily understandable to researchers doing applied welfare analysis.
Factors Affecting Welfare Gains From Fishing Gear Restrictions
Authors: Anderson Eric E.
Published: May 2019

While the use of gear restrictions to regulate fishing activity seldom has the objective of improving economic efficiency, it is capable of achieving that result under some conditions. It can also reduce economic efficiency. This paper explores the way several factors affect the sign and magnitude of welfare gains from fishing gear restrictions. These factors include, among others: the fixity or variability of the price of fish and the presence or absence of diminishing short-run average product of effort. Some generalizations are offered regarding the characteristics of fisheries in which gear restrictions are most likely to produce welfare gains.
Participation in Multiple-Peril Crop Insurance: Risk Assessments and Risk Preferences of Cranberry Growers
Authors: Dismukes R. A. , Allen P. G. , Morzuch B. J.
Published: May 2019

To investigate the poor participation rate of cranberry growers in the multiple-peril crop insurance program, a sample of 15 Massachusetts growers was interviewed. According to their risk preferences, a much greater proportion of growers should have insured, than actually did. A possible solution is to match the distribution used by the insurer closer to that believed by the grower. Adjusting each grower's historical yield series for trend brought the historical and subjective mean yields much closer. However, an aggregate test found the effect of adjustment to be insignificant, implying that the avenue for increased participation lies elsewhere.
Trade Gains and Welfare Costs of Income Stabilization Programs for Hog Producers in Quebec
Authors: Coffin H. Garth , Henning John C.
Published: May 2019

The welfare costs of deficiency payments for an exported commodity may, under certain conditions, outweigh the gains from trade. The potential welfare impacts of stabilization programs in the hog sector in Quebec are estimated, based on a partial equilibrium framework, and elasticity estimates drawn from other sources. The results indicate that the loss in surplus in Quebec as a result of deficiency payments is very modest at approximately $8.5 million or 1.7% of the value of production. Meanwhile, the net gains from trade remain on the order of $14 million.
Christmas Tree Consumption Behavior: Natural vs. Artificial
Authors: Hamlett Cathy Ann , Herrmann Robert O. , Warland Rex H. , Zhao Fengkun
Published: May 2019

Artificial Christmas trees have gained an increasing market share, causing concern to natural Christmas tree producers. Primary data was used to test a hypothesized sequential probit model of buyer characteristics. The model predicted the probability of using or displaying a Christmas tree, then if a use decision was made, the probability of displaying a natural tree. The people who are likely to display trees are Christian, practice other secular Christmas rituals, have children, and spend Christmas at home. Those who use natural trees are younger, white, have a higher income, and live in a single-family dwelling.
On Estimating Household Demand for Outdoor Recreation from Property Values: An Exploration
Authors: Edwards Steven F.
Published: May 2019

This paper explores how hedonic price analysis might be used to estimate the surplus benefits of local outdoor recreation when distance to the recreational site is captured in property values. The model is characterized by the endogenous choice of distance to a local recreational area by households in coastal property markets and by the capitalization of proximity in property values. Equilibrium occurs when the reduction in the cost of a property due to a marginal increase in distance to the recreational area equals the associated loss in recreational surplus resulting from increased travel costs. The theoretical model is applied in an exploratory analysis of the “demand” for distance to the nearest public beach from which total surplus benefits are estimated.
Market Structure and the Dynamics of Retail Food Prices
Authors: Weaver Robert D. , Chattin Peter , Banerjee Aniruddha
Published: May 2019

The effect of retail grocery market structure on the speed of adjustment of retail food prices to changes in producer prices, real wages, and the cost of energy was examined for SMSAs. Evidence failed to support the implication of the Mason-Bain paradigm that increased concentration reduces market efficiency as reflected in speed of retail price adjustment. Evidence of strong intertemporal relationships between change in producer prices and retail prices found for the categories meat, poultry, fish, eggs and cereal and baker products provide support to the hypothesis of cost-push inflation.
The Canada-U.S. Free Trade Agreement and Canada's Agri-Food Industries
Authors: Rugman Alan M. , Anderson Andrew
Published: May 2019

The food processing industry is Canada's second-largest manufacturing industry. It employed 226,579 people in 1986, and shipments were valued at CDN $47 billion, or 15 percent of the value of total manufactured output that year. More significantly, the food and beverage industries together ranked highest among all manufacturing industries in terms of value added, at CDN $15 billion or approximately 14 percent of total value added in Canadian manufacturing industries in 1986 (Statistics Canada). Given the high degree of competition in this industry in the United States, the history of “comfortable” competition in the food industry in Canada, and the significant contribution of this industry to the Canadian economy, it becomes important to look more carefully at how this industry has been and will be affected by the Canada-U.S. Free Trade Agreement (FTA).
Investment Behavior and Energy Conservation
Authors: LaDue Eddy L. , Miller Lynn H. , Kwiatkowski Joseph H.
Published: May 2019

Binary logit and bivariate probit models were used to investigate the investment behavior of farmers relative to two energy-conserving assets, heat-recovery systems and precoolers. The bivariate probit procedure was useful in correcting for self-selectivity bias. Holdout samples and cross-validation procedures were used to develop true model statistics. Farm size, educational level of the operator, and the type of milking system in use were the important factors influencing investment behavior.
Dichotomous-Choice, Contingent-Valuation Questions: Functional Form Is Important
Authors: Boyle Kevin J.
Published: May 2019

A variety of questioning formats have been used in contingent-valuation studies, with dichotomous-choice questions becoming the preferred format. However, as with any empirical technique, continued applications raise questions that require attention if the credibility of the procedure is to be maintained. It is shown that estimated Hicksian surplus can be substantially affected by the selection of a functional form when analyzing responses to dichotomous-choice questions. Given that theory, intuition, and empiricism all play a role in developing these estimates, several maxims are suggested for evaluating and/or mitigating such effects in future studies.
Modeling State Agriculture: An Application and Some Implications
Authors: Onafowora Olugbenga , D'Souza Gerard , Colyer Dale
Published: May 2019

A disaggregated econometric model of the agricultural sector at the state level is constructed. Using time series data on West Virginia agriculture and three-stage least squares in estimation, the model is employed to examine how various components of the state's agricultural sector adjust to changes in certain price and nonprice variables. Results reveal characteristics of the state's agricultural economy that are both unique and useful—characteristics that are usually masked in aggregate models but that have profound implications for modeling producer decision making and policy formulation.
Flow Associated With the Condensation and Sublimation of Polar Ice Caps on Mars
Authors: Chow Kim‐Chiu , Xiao Jing , Chan Kwing L. , Wong Chi‐Fong
Published: May 2019

The flow associated with the sublimation and condensation of carbon dioxide ice in the polar regions of Mars is an important part of the general circulation. However, so far the pattern of the flow is generally not well known. In this study, a Mars general circulation model (MarsWRF) has been applied to derive the pattern of this flow based on some specially designed experiments. The results suggest that the equatorward sublimation and the poleward condensation flows in both hemispheres are rather shallow except near the poles, and the strength of the sublimation flow is significantly stronger than the condensation flow in both hemispheres. The results also show that the strength of the sublimation and condensation flow in the southern hemisphere is much stronger than that in the northern hemisphere. During the summer time, the surface wind in the high‐latitude region near the pole could be dominated by the sublimation flow.
Implications for Thrust‐Related Shortening Punctuated by Extension From P‐T Paths and Geochronology of Garnet‐Bearing Schists, Southern (Çine) Menderes Massif, SW Turkey
Authors: Etzel T. M. , Catlos E. J. , Ataktürk K. , Lovera O. M. , Kelly E. D. , Çemen I. , Diniz E.
Published: May 2019

The Menderes Massif, Turkey, is a type locality for deciphering the plate tectonic response from collision‐ to extension‐driven exhumation. Conventional thermobarometry and garnet pressure‐temperature (P‐T) paths from isochemical phase diagrams were calculated across a major fault (Selimiye Shear Zone, SSZ) bounding the southern edge of the Menderes Massif. Both approaches yield similar garnet rim temperatures (from 555 to 671 °C), but estimated P differs by between 8 and 15 kbar. Three garnets north of the SSZ reveal N‐shaped P‐T paths, whereas paths from three samples south of the SSZ show a simple increase in P‐T. Monazite and zircon were dated in thin section from the same rocks using Secondary Ion Mass Spectrometry and Laser Ablation Inductively Coupled Plasma‐Mass Spectrometry, respectively. Textural relationships of monazite within garnet appears indicative of post‐garnet growth. The amount of monazite common 204Pb and 137Ba+/Th+ significantly exceeds what is observed for the monazite age standard, suggesting their ages mark fluid‐driven events, loosely constrained to Late Eocene‐Early Miocene. Some zircon ages are consistent with Cambro‐Ordovician ages reported elsewhere in the region, and other ages are Neoproterozoic and Permian‐Triassic, a period not previously recognized in this area. Despite the lack of age constraints for the duration of garnet growth, we present a thermal model to understand the meaning of the N‐shaped path. These paths are best reproduced by thermal models incorporating SSZ thrusting before and after denudation. This paper presents an example of the insight from high‐resolution P‐T paths, and an example of denudation within a prograde metamorphic event.
When Water Met Rock
Authors: Joel Lucas
Published: May 2019

Geologists discover rocks bearing the earliest known evidence of water interacting with rock on Earth’s surface.
Temperature and Gas/Brine Content Affect Seismogenic Potential of Simulated Fault Gouges Derived From Groningen Gas Field Caprock
Authors: Hunfeld Luuk B. , Chen Jianye , Niemeijer André R. , Spiers Christopher J.
Published: May 2019

We investigated the rate‐and‐state frictional properties of simulated anhydrite‐carbonate fault gouge derived from the basal Zechstein caprock overlying the seismogenic Groningen gas reservoir in the NE Netherlands. Direct shear experiments were performed at in situ conditions of 50–150 °C and 40‐MPa effective normal stress, using sliding velocities of 0.1–10 μm/s. Reservoir pore fluid compositions were simulated using 4.4 Molar NaCl brine, as well as methane, air, and brine/gas mixtures. Brine‐saturated samples showed friction coefficients (μ) of 0.60–0.69, with little dependence on temperature, along with velocity strengthening at 50–100 °C, transitioning to velocity weakening at 120 °C and above. By contrast, gas filled, evacuated and partially brine‐saturated samples showed μ values of 0.72 ± 0.02 plus strongly velocity‐weakening behavior accompanied by stick slip at 100 °C (the only temperature investigated for gas‐bearing and dry samples). A microphysical model for gouge friction, assuming competition between dilatant granular flow and thermally activated compaction creep, captures the main trends seen in our brine‐saturated samples but offers only a qualitative explanation for our gas‐bearing and dry samples. Since the reservoir temperature is ~100 °C, our results imply high potential for seismogenic slip nucleation on faults that cross cut and juxtapose the basal Zechstein anhydrite‐carbonate caprock against the Groningen reservoir sandstone, specifically in the gas‐filled upper portion of the reservoir system.
Response of the Ionosphere‐Plasmasphere Coupling to the September 2017 Storm: What Erodes the Plasmasphere so Severely?
Authors: Obana Yuki , Maruyama Naomi , Shinbori Atsuki , Hashimoto Kumiko K. , Fedrizzi Mariangel , Nosé Masahito , Otsuka Yuichi , Nishitani Nozomu , Hori Tomoaki , Kumamoto Atsushi , Tsuchiya Fuminori , Matsuda Shoya , Matsuoka Ayako , Kasahara Yoshiya , Yoshikawa Akimasa , Miyoshi Yoshizumi , Shinohara Iku
Published: May 2019

We report an extreme erosion of the plasmasphere arising from the September 2017 storm. The cold electron density is identified from the upper limit frequency of upper hybrid resonance waves observed by the Plasma Wave Experiment instrument onboard the Exploration of energization and Radiation in Geospace/Arase satellite. The electron density profiles reveal that the plasmasphere was severely eroded during the recovery phase of the storm and the plasmapause was located atL= 1.6–1.7 at 23 UT 8 September 2017. This is the first report of deep erosion of the plasmasphere (LPP< 2) with the in situ observation of the electron density. The degree of the severity is much more than what is expected from the relatively moderate value of the SYM‐H minimum (−146 nT). We attempt to find a possible explanation for the observed severe depletion by using both observational evidence and numerical simulations. Our results suggest that the middle latitude electric field had penetrated from the high‐latitude storm time convection for several hours. Such an unusually long‐lasting penetration event can cause this observed degree of severity.
A flexible and multifunctional metal–organic framework as a matrix for analysis of small molecules using laser desorption/ionization mass spectrometry
Authors: Ma Wen , Xu Shuting , Ai Wanpeng , Lin Cheng , Bai Yu , Liu Huwei
Published: May 2019

Fast screening of multi-functional MOFs as SALDI-MS matrices for the detection of small molecules and simultaneous enrichment and detection of analytes.
Charge, adsorption, water stability and bandgap tuning of an anionic Cd(ii) porphyrinic metal–organic framework
Authors: Li Qi , Luo Yanping , Ding Yue , Wang Yina , Wang Yuxin , Du Hongbin , Yuan Rongxin , Bao Jianchun , Fang Min , Wu Yong
Published: May 2019

By changing the occupancies of the metal ions and counterions, the tuning of the framework charge, band-edge position and bandgap of a novel Cd(ii) porphyrinic MOF 1 was achieved.
Preparation of 2-arylquinolines from β-arylpropionitriles with aryllithiums and NIS through iminyl radical-mediated cyclization
Authors: Naruto Hiroki , Togo Hideo
Published: May 2019

Treatment of β-arylpropionitriles with aryllithiums, followed by the reaction with water and then with NIS under irradiation with a tungsten lamp gave 2-arylquinolines in good to moderate yields.
Eye movements during change detection: the role of depth of field
Authors: Zhang Tingting , Xia Ling , Liu Xiaofeng , Wu Xiaoli
Published: May 2019

This study investigates the eye movements when detecting changes in the scene with different levels of depth of field. A within‐subjects experiment was conducted using a flicker paradigm to create change blindness phenomenon. This experiment investigated two main factors: depth of field and position. The eye‐tracker Tobii X120 was used to record participants’ eye movements when looking for changes in the flickering scenes. It was concluded that a small depth of field could indeed direct viewers’ attention into the sharp area. The size of the depth of field could not influence the amount of time for change detection whereas uniform blur could facilitate change detection.
Generative recursive network for constructive solid geometry
Authors: Zhang Yang , Liu Zhen , Li Xiang , Wei Xizhang , Zhang Qianyu
Published: May 2019

Constructive solid geometry (CSG) is a technique to create a complex 3D object by using boolean operators to combine simple primitives. However, it is very challenging to obtain programs from 3D models, the inverse of the constructing process. In this Letter, the authors propose a generative recursive network for the inverse problem, which is composed of several kinds of specially designed sub‐networks to get CSG programs directly from the input 3D model. Compared with previous methods, the authors' method can deal with various lengths and structures of programs, does not limit to specific primitives and can generate programs of very similar structures with the input.
Comparison of three interval arithmetic‐based algorithms for antenna array pattern upper bound estimation
Authors: He Guolong , Gao Xin , Zhou Hui , Zhu Hongquan
Published: May 2019

This Letter reveals the underlying relations of three state‐of‐the‐art interval arithmetic (IA)‐based algorithms for antenna array pattern upper bound estimation with excitation amplitude errors. Theoretical analysis proves that the matrix IA algorithm has better performance than both the rIA and circular IA algorithms. Mathematical derivations are presented in detail, and representative numerical examples are given for validating this conclusion.
Analytical expressions of the Q‐factor for the complete resonant mode spectrum of the equilateral triangular waveguide cavity
Authors: Morán‐López Ana , Ruiz‐Cruz Jorge A. , Córcoles Juan , Montejo‐Garai José R. , Rebollar Jesús M.
Published: May 2019

This Letter presents the closed‐form expressions of the unloaded Q‐factor in metallic cavities with equilateral triangular cross section, computed from its analytical resonant mode solutions. The obtained analytical formulas for the Q‐factor extend the very restricted range of problems with closed‐form solutions, complementing the classic cases of the rectangular and circular cavities found in the literature. The presented derivation provides extremely rapid reference solutions for diverse applications such as filter design by test cases for microwave characterisation systems or numerical full‐wave solvers. A universal Q‐chart, valid for any aspect ratio, is given and the achieved analytical results for the first resonant modes are tested with numerical commercial software, showing excellent agreement.
Oscillation instability of a DC microgrid caused by aggregation of same CPLs in parallel connection
Authors: Du Wenjuan , Zheng Kaiyuan , Wang HaiFeng
Published: May 2019

The authors found that aggregation of same constant power loads (CPLs) in the parallel connection may possibly cause oscillation instability of a DC microgrid. In this study, they carry out analysis to reveal the mechanism about why the danger of oscillation instability may be brought about by the aggregation of CPLs in parallel connection. By assuming that the dynamic models of N CPLs in parallel connection are identical, analysis in this study proves that aggregated representation of the CPLs is equivalently comprised of N dynamically independent subsystems. Oscillation modes of aggregated CPLs may possibly move toward the right on the complex plane when the number of CPLs, N, increases. They propose a method to estimate the direction of movement of oscillation modes when N varies without having to conduct the modal solution of full‐order state matrix. Thus, the proposed method can detect the danger of oscillation instability caused by aggregation of CPLs in parallel connection and estimate the maximum number of CPLs when the oscillation instability may occur. They present two examples DC microgrids with aggregated CPLs in parallel connection to evaluate the analytical conclusions. Application of the proposed method in planning the grid connection of CPLs is demonstrated.
Modelling and simulation of KHLMS algorithm‐based DSTATCOM
Authors: Mangaraj Mrutyunjaya , Panda Anup Kumar
Published: May 2019

The assessment of the shunt compensation allied power quality glitches bounds the design and modelling of a controller for the d‐FACTS (Distribution Flexible Alternating current Transmission System) device. So, Kernel Hebbian least mean square (KHLMS) is proposed for controlling the distributed static compensator (DSTATCOM) in this study. The KHLMS is the improved version of an adaptive LMS (ALMS), which is designed by using a suitable pattern of learning mechanism. Both the controller algorithms are formulated on the basis of mathematical equations using MATLAB/Simulink. In accordance with the system variation adaptability and experimental application, each phase controller is configured as an independent neural network structure. The objective of control algorithms is used for the extraction of fundamental active and reactive components from load currents for the generation of the reference source currents. In comparison with the ALMS algorithm, the KHLMS demonstrates more effective in improving the voltage regulation at DC link capacitor, voltage balancing, source current harmonic reduction, and power factor correction under the disturbance influences caused by even and uneven loading.
Particle swarm optimisation‐based model and analysis of photovoltaic module characteristics in snowy conditions
Authors: Khenar Mohammad , Hosseini Seyedkazem , Taheri Shamsodin , Cretu Ana‐Maria , Pouresmaeil Edris , Taheri Hamed
Published: May 2019

In this study, a novel methodology of photovoltaic (PV) modelling is proposed to represent the instantaneous electrical characteristics of PV modules covered with snow. The attenuation of the transmitted solar radiation penetrating a layer of snow is rigorously estimated based on the Giddings and LaChapelle theory. This theory introduced the level of radiation that reaches the surface of the PV module through the snowpack, significantly affected by the snow properties and thickness. The proposed modelling approach is based on the single‐diode‐five‐parameter equivalent circuit model. The parameters of the model are updated through instantaneous measurements of voltage and current that are optimised by the particle swarm optimisation algorithm. The proposed approach for modelling snow‐covered PV modules was successfully validated in outdoor tests using three different types of PV module technologies typically used in North America's PV farms under different cold weather conditions. In addition, the validity of the proposed model was investigated using real data obtained from the SCADA system of a 12‐MW grid‐connected PV farm. The proposed model can help to improve PV performance under snow conditions and can be considered a powerful tool for the design and selection of PV modules subjected to snow accretion.
Location and size determination method of SFCLs in multi‐terminal VSC‐HVDC using iterative current reduction ranking
Authors: Lan Tongkun , Li Yinhong , Duan Xianzhong , Xiao Hao
Published: May 2019

Superconducting fault current limiter (SFCL) is a promising technology to suppress fault current in multi‐terminal VSC‐HVDC. However, the location and size of SFCLs determination have become a problem to be studied. This study proposes a location and size determination method of SFCLs in multi‐terminal VSC‐HVDC. In the proposed method, the current reduction ranking is developed to quantify the current limiting effect, and iterative process is utilised to deal with the non‐linear characteristics of current reduction. With the iterative current reduction ranking, the location and size could be determined collaboratively under mathematical guidance, ensuring the optimality of current limiting effect. Fast calculation of current reduction is investigated to accelerate the determination process. Finally, the effectiveness and feasibility of the proposed method are validated in a four‐terminal VSC‐HVDC.
Harvesting wind gust energy with small and medium wind turbines using a bidirectional control strategy
Authors: Sajadi Milad , De Kooning Jeroen D. M. , Vandevelde Lieven , Crevecoeur Guillaume
Published: May 2019

Wind energy is an important renewable source with a stochastic nature. To capture this energy, variable speed generators are installed in wind towers and different maximum power point (MPP) tracking (MPPT) strategies have been developed in literature to maximise the output power. However, in gusty weather, wind turbines fail to track the optimum operating point due to their relatively high inertia. This paper proposes an innovative MPPT strategy to capture the energy of wind gusts. The developed controller consists of a conventional TSR control together with a bidirectional controller, which takes over the control of the rectifier under varying wind condition. The simulation results show an overall efficiency improvement and more stability for the proposed strategy.
Next‐generation integrated drive: A high power density permanent magnet synchronous drive with flooded stator cooling
Authors: Ullah Sana , Winterborne Dave , Lambert Simon M.
Published: May 2019

The next‐generation integrated drive (NGID) is an 80 kW demonstrator showcasing the latest innovations in high power density electric drive technology. A prototype 30 krpm maximum speed permanent magnet synchronous machine for an automotive traction application is under construction. This study describes several aspects of the detailed design and how these fit together in the complete drive package to increase the power density of the NGID.
Design of a cost‐effective magnetic gearbox for an aerospace application
Authors: Benarous Maamar , Trezieres Marlene
Published: May 2019

Magnetic gears are designed to perform in a highly reliable manner, and offer several advantages compared to mechanical gears but difficulties with manufacturing techniques and cost are strong handicaps. In contrast to conventional gears, the contact and lubrication free force transmitting elements lead to a considerable lifetime and range extension of drive systems. In recent years, magnetic gears have been extensively researched and discussed by both academics and engineers from different industries. However, the vast majority of published work on magnetic gearing relates to novel topologies and performance improvement but not on optimisation of cost and weight. With a judicious parametric model analysis, design can be optimised in terms of torque capability, cost and weight. Moreover, the design process is time and cost consuming, but can be also be reduced by the use of modelling methods. An earlier paper addressed the parametric model approach and its benefits, but did not include a comparison between test and simulation data. This study will summarise the findings and present the test data from a magnetic gearbox designed for an aerospace application such as a high lift system.
Detection of humidity ingress using online common‐mode insulation impedance‐monitoring system
Authors: Tsyokhla Igor , Griffo Antonio , Wang Jiabin
Published: May 2019

Enhanced machine reliability through monitoring of its state of health is an emerging field of research. Ingress of contaminants such as moisture can effect electrical machine state of health and contribute to failure in winding insulation. This paper demonstrates the application of an online insulation health monitoring method to study the effect of moisture ingress on ground‐wall insulation through practical experiment. The method, based on real‐time high‐frequency leakage current measurement, is implemented on a 2.83 kW machine during operation in open‐loop configuration. The results are presented and discussed, demonstrating the feasibility of diagnosis of moisture ingress.
Induction of Labour in Growth Restricted and Small for Gestational Age Foetuses – A Historical Cohort Study
Authors: Kehl Sven , Weiss Christel , Dammer Ulf , Berlit Sebastian , Große-Steffen Thomas , Faschingbauer Florian , Sütterlin Marc , Beckmann Matthias , Schneider Michael
Published: May 2019

Purpose Induction of labour for small-for-gestational-age (SGA) foetus or intrauterine growth restriction (IUGR) is common, but data are limited. The aim of this study was therefore to compare labour induction for SGA/IUGR with cases of normal foetal growth above the 10th percentile.

Material and Methods This historical multicentre cohort study included singleton pregnancies at term. Labour induction for SGA/IUGR (IUGR group) was compared with cases of foetal growth above the 10th percentile (control group). Primary outcome measure was caesarean section rate.

Results The caesarean section rate was not different between the 2 groups (27.0 vs. 26.2%, p = 0.9154). In the IUGR group, abnormal CTG was more common (30.8 vs. 21.9%, p = 0.0214), and foetal blood analysis was done more often (2.5 vs. 0.5%, p = 0.0261). There were more postpartum transfers to the NICU in the IUGR group (40.0 vs. 12.8%, p < 0.0001), too.

Conclusion Induction of labour for foetal growth restriction was not associated with an increased rate of caesarean section.
The Effect of Intrauterine Administration of Human Chorionic Gonadotropin (hCG) Before Embryo Transfer During Assisted Reproductive Cycles: a Meta-Analysis of Randomized Controlled Trials
Authors: Tan Huiping , Hu Shifu , Chen Yuan , Jin Lei , Wu Chunlin ,   Qiongyu
Published: May 2019

The fertility success rates of clinical and laboratory-assisted reproductive techniques (ART) remain low, despite major advances. The aim of this study was to conduct a systematic literature review and assess whether the intrauterine administration of human chorionic gonadotropin (hCG) before embryo transfer (ET) improved the clinical outcomes of sub-fertile women undergoing assisted reproduction. The electronic databases PUBMED, EMBASE and Web of Science were systematically searched for randomized controlled trials (RCTs) published from inception to June 2018. The trial data were independently extracted and analyzed using risk ratios (RRs) and 95% confidence intervals (CIs) according to a random- or fixed-effect model (as appropriate), and a meta-analysis was conducted using Review Manager 5.2 software. The meta-analysis included 3241 patients from 12 RCTs, and the combined results demonstrated that intrauterine hCG injection significantly improved the rates of clinical (RR = 1.33; 95% CI: 1.12 – 1.58) and ongoing pregnancy (RR = 1.87; 95% CI: 1.54 – 2.27), compared with controls. However, intrauterine hCG injection had no significant effect on the implantation rate (RR = 1.30; 95% CI: 0.89 – 1.90), abortion rate (RR = 1.06; 95% CI: 0.78 – 1.44), ectopic pregnancy rate (RR = 0.77; 95% CI: 0.17 – 3.42) or live birth rate (RR = 0.99; 95% CI: 0.60 – 1.63). In a subgroup analysis, the intrauterine injection of > 500 IU hCG led to a significant increase in the implantation rate (RR = 1.64; 95% CI: 1.04 – 2.61) relative to controls. Furthermore, the subgroup of women with cleavage-stage ETs who received an intracavity injection of hCG (IC-hCG) exhibited increases in the implantation, clinical pregnancy and ongoing pregnancy rates, compared to women with cleavage-stage ETs and no IC-hCG. The current evidence indicates that intrauterine hCG administration before ET provides an advantage in terms of the clinical pregnancy and ongoing pregnancy rates.
Lungenfunktion, Lung Clearance Index und bronchiale Entzündung bei Kindern und Jugendlichen mit Bronchiolitis obliterans
Authors: Belachew N. , Jerkic S. , Michel F. , Schubert R. , Zielen S. , Rosewich M.
Published: May 2019

Einleitung Die Bronchiolitis obliterans (BO) ist eine sehr seltene, chronische Lungenerkrankung, die vereinzelt nach schweren Atemwegsinfektionen oder als Folge von Stammzell- und Lungentransplantation auftritt. Ziel der Arbeit war es, die Lungenfunktion und die bronchiale Entzündung bei BO-Patienten im Jugend- und Kindesalter zu untersuchen. Zudem sollte das Potenzial des LCI in der Diagnostik dieser Patienten untersucht werden.

Methoden Es wurden 16 BO-Patienten (Alter: Median 16,7; 9,6 – 25,3 Jahre) und 17 gesunde Probanden (Alter: Median 16,6; 7,6 – 25,0 Jahre) untersucht. Neben der Untersuchung der Lungenfunktion (FVC, FEV1, MEF25, RV und RV/TLC) mittels Bodyplethysmografie erfolgte eine Reversibilitätstestung nach Gabe von 400 µg Salbutamol. Die Bestimmung des LCI erfolgte mittels Multiple Breath Washout (MBW)-Methode. Zusätzlich wurde die Zellverteilung und das Zytokinprofil (IL-1ß, IL-6, IL-8, TNF-α) mittels Cytometric Bead Array (CBA) im induzierten Sputum analysiert.

Ergebnisse FVC, FEV1 und MEF25 der BO-Patienten waren signifikant niedriger, das RV und die RV/TLC jedoch signifikant erhöht im Vergleich zur Kontrollgruppe. Eine bronchiale Reversibilität zeigte sich bei 3 Patienten. Der LCI war bei den BO-Patienten gegenüber der Kontrollgruppe signifikant erhöht (Median 10,24 vs. 7,1) und korrelierte signifikant mit dem MEF25 (p < 0,0001). Im induzierten Sputum fand sich eine signifikante Erhöhung der Gesamtzellzahl, der neutrophilen Granulozyten sowie von IL-6 und IL-8 (p < 0.01).

Schlussfolgerung Die Lungenfunktion ist bei Kindern und Jugendlichen mit BO stark eingeschränkt. Zudem erwies sich der LCI als sensitiver und reproduzierbarer Marker zur Beurteilung der obstruktiven Beeinträchtigung der kleinen Atemwege. Im induzierten Sputum ist eine von Neutrophilen dominierte bronchiale Entzündung nachweisbar.