bluuebunny/crossref_metadata_2025_split huggingface dataset:
Military pregnancies and adverse perinatal outcome
Authors: Magann E.F. , Winchester M.I. , Carter D.P. , Martin J.N. , Nolan T.E. , Morrison J.C. 
Published: July 2002

AbstractObjective: To identify significant risk factors for an adverse outcome in active‐duty military women. Method: A prospective study of 105 pregnancies and their outcome. Results: The data revealed that: (1) single women more than married personnel had cesarean births when compared with forceps and vacuum (P < 0.03) or spontaneous vaginal delivery (P < 0.04); and (2) active‐duty women who gained <25 pounds during pregnancy developed preterm labor more often (P < 0.05). Conclusion: Risk factors for these adverse outcomes remain unknown.
Third‐trimester maternal serum β‐HCG level and umbilical blood flow in fetal growth retardation
Authors: Bartha J.L. , Comino‐Delgado R. , Arrabal J. , Escobar M.A. 
Published: July 2002

AbstractObjective: To determine the relationship between maternal serum β‐HCG level and umbilical artery systolic/diastolic ratio in fetal growth retardation. Methods: Maternal serum β‐HCG was measured in 57 pregnant women in the third trimester, 31 with a fetal growth retardation and 26 with a normal growth. The systolic/diastolic ratio was measured in a midsection of the umbilical cord the same day of the biochemical determination. Results: The serum β‐HCG level was statistically significant higher in pregnant women with a fetal growth retardation associated with a high systolic/diastolic ratio (n = 9) (P < 0.001). There were no differences between the fetuses with a normal growth (n = 26) and those with an intrauterine growth retardation and a normal systolic/diastolic ratio (n = 22). There was a significant positive correlation between maternal serum β‐HCG level and umbilical artery systolic/diastolic ratio (P < 0.01). Conclusion: Fetal growth retardation due to Doppler‐defined vascular placental insufficiency is associated with a higher maternal serum β‐HCG level.
Arcs of integration: an international study of supply chain strategies
Authors: Frohlich Markham T. , Westbrook Roy 
Published: July 2002

AbstractThough there is a wide acceptance of the strategic importance of integrating operations with suppliers and customers in supply chains, many questions remain unanswered about how best to characterize supply chain strategies. Is it more important to link with suppliers, customers, or both? Similarly, we know little about the connections between supplier and customer integration and improved operations performance. This paper investigated supplier and customer integration strategies in a global sample of 322 manufacturers. Scales were developed for measuring supply chain integration and five different strategies were identified in the sample. Each of these strategies is characterized by a different “arc of integration”, representing the direction (towards suppliers and/or customers) and degree of integration activity. There was consistent evidence that the widest degree of arc of integration with both suppliers and customers had the strongest association with performance improvement. The implications for our findings on future research and practice in the new millennium are considered.
The discipline of real cells
Authors: Hyer Nancy Lea , Brown Karen A 
Published: July 2002

AbstractCellular manufacturing (CM) has received strong endorsement as an innovation that enhances quality, throughput time, inventory turnover, workflow, space utilization, and flexibility [Nyman, L. (Ed.), 1992. Making Manufacturing Cells Work. Society of Manufacturing Engineers, Dearborn, MI.]. However, definitions of what truly is meant by the term ‘manufacturing cell’ vary somewhat among academics and to a large extent among practitioners [Shafer S.M., Meredith, J.M., Marsh, R.F., 1995. Omega 23(4), 361–376.]. These discrepancies can make it difficult to compare the results of studies focused on measuring the effectiveness of cells. It is our position that some of the confusion in the field derives from an assumption that a cell is simply a layout—nothing more—leaving room for numerous approaches to cell design and operation. Our goal in writing this paper is to suggest a more comprehensive perspective. Based on our ongoing field research and an exploration of the literature, we propose an underlying theory to describe the discipline necessary for effective cell operation. We differentiate real cells from other types of cells based on the presence of key linkages. In a real cell, work tasks and those who perform them are connected in terms of time, space and information. Of these linking mechanisms, which represent the core of the cell discipline, information appears to be the most significant determinant of effectiveness. Additionally, we emphasize that cell operators are central to the discipline, underscoring our position that a cell is more than an arrangement of equipment. Factors such as multi‐skilling, reduced set‐up times, small transfer batch size, and the presence of visual controls serve as enablers that strengthen the discipline, but are not fundamental to our theoretical definition. Configurations not adhering to the discipline of time, space, and information may be classified as latent or virtual cells, and may be expected to perform at levels less than those of real cells. Although our theory of cell discipline is grounded in observational study, its potential robustness will be confirmed most appropriately through carefully designed and executed field experiments.
Development, test reliability and validation of a classification for revision hip arthroplasty
Authors: Saleh Khaled J. , Holtzman Jeremy , Gafni Amiram , Saleh Lena , Jaroszynski Grzeogrz , Wong Paul , Woodgate Ian , Davis Aileen , Gross Allan E. 
Published: July 2002

AbstractThe objective of the study was to develop a valid and reliable classification system for failed hip arthroplasties. The study uses research principals derived from multi‐attribute utility theory and consensus group techniques. The development of the severity measure was done in two phases. Phase I of the study included: (a) questionnaire development, (b) submission of the questionnaire to the respondents, (c) data synthesis of the responses and item reduction, and (d) classification development and inter‐observer reliability testing. Phase II included: (a) resubmission of the instrument to the respondents for suggestions/feedback. (b) instrument revision by the co‐investigators based on the respondents' second feedback, and (c) inter‐observer reliability testing and intraoperative validity testing of the instrument. The questionnaires sought to capture expert opinion as to what clinical determinants obtained preoperatively (during patient interview, physical exam and review of plain radiographs – AP pelvis and hip lateral) that would in their clinical experience reveal intraoperative severity. There was an 80% (16/20) response rate from the outside experts invited to participate in the study. Based on item reduction and test‐retest analysis, a five‐grade radiographic classification for the acetabulum as well as the femur was developed. This system was then reviewed by 13 of the initial outside experts (16, 80%) who participated in the first round. Inter‐rater reliability testing of the final format of the classification revealed a weighted kappa statistic value of 0.88 between the two‐blinded raters (inter‐rater reliability) and 0.87 between the blinded raters and the reference standard (intraoperative validity). We conclude that the study developed a reliable and valid radiographic classification system for failed hip arthroplasty. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Age and ovariectomy impair both the normalization of mechanical properties and the accretion of mineral by the fracture callus in rats
Authors: Meyer Ralph A. , Tsahakis Paul J. , Martin David F. , Banks David M. , Harrow Matt E. , Kiebzak Gary M. 
Published: July 2002

AbstractThe impact of age and ovariectomy on the healing of femoral fractures was studied in three groups of female rats at 8, 32 and 50 weeks of age at fracture. In the two older groups, the rats had been subjected to ovariectomy or sham surgery at random at 26 weeks of age. At fracture, all rats received unilateral intramedullary pinning of one femur and a middiaphyseal fracture. Rigidity and breaking load of the femora were evaluated at varying times up to 24 weeks after fracture induction by three‐point bending to failure. Bone mineral density (BMD) was measured by dual‐energy X‐ray absorptiometry. In the youngest group, 8‐week‐old female rats regained normal femoral rigidity and breaking load by 4 weeks after fracture. They exceeded normal contralateral values by 8 weeks after fracture. In the middle group, at 32 weeks of age, fractures were induced, and the femora were harvested at 6 and 12 weeks after fracture. At 6 weeks after fracture there was partial restoration of rigidity and breaking load. At 12 weeks after fracture, only the sham‐operated rats had regained normal biomechanical values in their fractured femora, while the fractured femora of the ovariectomized rats remained significantly lower in both rigidity and breaking load. In contrast, for the oldest group of rats, 50 weeks old at fracture, neither sham‐operated nor ovariectomized rats regained normal rigidity or breaking load in their fractured femora within the 24 weeks in which they were studied. In all fractured bones, there was a significant increase in BMD over the contralateral intact femora due to the increased bone tissue and bone mineral in the fracture callus. Ovariectomy significantly reduced the BMD of the intact femora and also reduced the gain in BMD by the fractured femora. In conclusion, age and ovariectomy significantly impair the process of fracture healing in female rats as judged by measurements of rigidity and breaking load in three‐point bending and by accretion of mineral into the fracture callus. © 2001 Orthopaedic Research Society. Published by Elsevier Science Ltd. All rights reserved.
Spontaneous embryonic motility: an enduring legacy
Authors: Bekoff Anne 
Published: July 2002

AbstractThis chapter addresses the influential contributions Viktor Hamburger has made to our understanding of embryonic motor behavior. With his classic review, published in 1963, Viktor Hamburger opened up the field of embryonic motor behavior, which had lain almost completely dormant for many years. He focused his observations and experimental studies on the spontaneously generated embryonic movements rather than on reflex responses. As a result, he and his colleagues firmly established the central generation of embryonic motility as a basic component of embryonic behavior in chicks. These studies were also extended to rat fetuses, showing that similar principles apply to mammalian fetuses. All of us who have followed after him owe Viktor Hamburger an enormous debt of gratitude for his pioneering work.
Involvement of P2 purinoceptors in the regulation ofdna synthesis in the neural retina of chick embryo
Authors: Sugioka Miho , Zhou Wen‐liang , Hofmann Hans‐dieter , Yamashita Masayuki 
Published: July 2002

AbstractThe activation of P2 purinoceptors induces Ca2 mobilization in the earlyembryonic chick neural retina. This purinergic Ca2 response declines parallel with thedecrease in mitotic activity during retinal development. To investigate the role of P2purinoceptors in the regulation of retinal cell proliferation, we studied the effects of the P2purinoceptor antagonists suramin and pyridoxalphosphate‐6‐azophenyl‐2′,4′‐disulphonic acid (PPADS), and of the agonist ATP on DNA synthesis in retinal organcultures from embryonic day 3 (E3) chick. Suramin inhibited [3H]‐thymidineincorporation in a dose‐dependent manner (IC50 : ∼70 μM). PPADS alsoreduced [3H]‐thymidine incorporation with maximum inhibition of 46% at 100 μM. Exogenous ATP enhanced [3H]‐thymidine incorporation in adose‐dependent manner to maximally 200% of control (EC50 : ∼70 μM). Indissociated retinal cultures from E7 chick, both antagonists showed similar inhibitory effects on [3H]‐thymidine incorporation without affecting cell viability. In line with theseobservations, the presence of extracellular ATP was demonstrated both in vitro and in vivo. In the medium of E3 retinal organ cultures, the concentration of ATP increased25‐fold within 1 h of incubation and this concentration was kept for at least 24 h. In the chickamniotic fluid, the ATP concentration was nearly 3 μM at E3 and declined to 0.15 μM at E7. The results indicate that P2 purinoceptors activated by autocrine or paracrinerelease of ATP are involved in the regulation of DNA synthesis in the neural retina at earlyembryonic stages.
The role of serotonin in depression and anxiety
Authors: Deakin JFW 
Published: July 2002

SummaryThe different coping responses to three types of aversive events - future threats, acute events and chronic stress — may be modulated by 5HT projections. Dysfunction in these coping mechanisms could cause, respectively: generalised anxiety disorder, panic, and depression. This theory proposes that dorsal raphe nucleus projections to 5HT2 and 5HT1D receptors mediate anticipatory anxiety and normally motivate avoidance of threats. The brain aversion system may be held in check by dorsal raphe nucleus 5HT projections to mediate behavioural inhibition during anticipatory anxiety. Proximal aversive stimuli such as pain and asphyxia elicit the fight-flight reflex mediated by the amygdala-hypothalamic-periaqueductal grey brain aversion system. Panic attacks may thus be due to spontaneous activation of this system. Median raphe projections to 5HT1A receptors have been implicated in adaptation to chronic stress-resilence. There is good evidence that 5HT1A function breaks down in depression and causes the depressed state. Experimental tests of this theory suggest that viewing anxiety, panic, and depression as dysfunctions in neurochemically and anatomically specific coping systems is heuristically useful.
Mapping the Trap‐State Landscape in 2D Metal‐Halide Perovskites Using Transient Photoluminescence Microscopy
Authors: Seitz Michael , Meléndez Marc , Alcázar‐Cano Nerea , Congreve Daniel N. , Delgado‐Buscalioni Rafael , Prins Ferry 
Published: February 2021

AbstractTransient microscopy is of vital importance in understanding the dynamics of optical excited states in optoelectronic materials, as it allows for a direct visualization of the movement of energy carriers in space and time. Important information on trap‐state dynamics can be obtained using this technique, typically observed as a slow‐down of energy transport as carriers are trapped at defect sites. To date, however, studies of the trap‐state dynamics have been mostly limited to phenomenological descriptions of the early time‐dynamics. Here, it is shown how long‐acquisitiontime transient photoluminescence microscopy can be used to provide a detailed map of the trapstate landscape in 2D perovskites, in particular when used in combination with transient spectroscopy. An anomalous evolution of the studied exciton distribution is observed, which cannot be explained with existing models for trap limited exciton transport that only account for a single trap type. Instead, using a continuous diffusion model and performing Brownian dynamics simulations, it is shown that this behavior can be explained by accounting for a distinct distribution of traps in this material. These results highlight the value of transient microscopy as a complementary tool to more common transient spectroscopy techniques in the characterization of excited state dynamics in semiconductors.
Recent trends in the chromatographic analysis of volatile flavor and fragrance compounds: Annual review 2020
Authors: Louw Stefan 
Published: February 2021

AbstractThe chromatographic analysis of volatile flavor and fragrance compounds is performed routinely in several industries and in many fields of scientific research. Typical applications include food‐, environmental‐, essential oil‐ and cosmetics analysis. Even though the analysis of flavors and fragrances have become increasingly standardized during the past decade, there are still a large variety of techniques that can be used for their extraction, chemical analysis, and sensory analysis. Moreover, there are certain less commonly used techniques that are now being used with increased frequency and that are showing the potential of being used as alternatives to the existing standard techniques. In this annual review, the techniques that were most commonly used in 2020 for the investigation of these volatile compounds are discussed. In addition, a number of emerging trends are discussed, notably the use of solvent assisted flavor evaporation (SAFE) for extraction, GC ion mobility spectrometry (IMS) for volatile compound analysis and electronic senses, that is, E‐noses and E‐tongues, for sensory analysis. Miscellaneous hyphenated techniques, advances in stationary phase chemistry and a number of interesting applications are also highlighted.
Vorgespannte Trockenfugen für modulare Brücken unter zyklischer Belastung
Authors: Schaarschmidt David , Flederer Holger 
Published: February 2021

AbstractModulares Bauen mit Betonfertigteilen gewinnt in den letzten Jahren verstärkt an Bedeutung. Aktuelle Entwicklungen in Praxis und Forschung untersuchen das Fügen der einzelnen Module völlig ohne Ortbeton, Vergussmörtel, Klebung oder Schubnocken. Eine Möglichkeit zur Kraftübertragung bietet das Aktivieren der Oberflächenreibung mittels Vorspannung. Während die Schertragfähigkeit maßgeblich vom Haftreibungsbeiwert abhängt, ist die Biegetragfähigkeit an die Dekompression der Trockenfuge gebunden. Aus statischer Sicht ist die wirklichkeitsnahe Beurteilung der Oberflächentopographie essentiell. In der DIN EN 1992‐1‐1 wird diese in vier Stufen von sehr glatt bis verzahnt eingeteilt, wodurch die Vielzahl an unterschiedlichen Oberflächenqualitäten nur grob abgebildet wird. Darüber hinaus ist die uneingeschränkte Übertragbarkeit des Coulombschen Reibungsgesetzes auf den Beton, vor allem bei höheren Druckspannungen in der Fuge, zu überprüfen. Zwei nennenswerte Anwendungsfelder des modularen Bauens stellen Brückenbauwerke und Windenergieanlagen dar. Beide Bauwerksgruppen unterliegen vorwiegend nichtruhenden Belastungen, welche ermüdungsrelevante Beanspruchungen im Kontaktbereich hervorrufen. Um dauerhafte, ermüdungsresistente und sichere Bauwerke zu errichten, müssen die maßgeblichen Beanspruchungscharakteristika sowie deren Auswirkungen auf die Kontaktoberfläche und die Betonmatrix identifiziert und untersucht werden.
Predicting 2‐year all‐cause mortality after contemporary PCI: Updating the logistic clinical SYNTAX score
Authors: Chichareon Ply , van Klaveren David , Modolo Rodrigo , Kogame Norihiro , Takahashi Kuniaki , Chang Chun‐Chin , Tomaniak Mariusz , Yuan Jinqing , Xie Lihua , Song Ying , Qiao Shubin , Yang Yuejin , Guan Changdong , Zurakowski Aleksander , van Geuns Robert‐Jan , Sabate Manel , Ong Paul J. , Wykrzykowska Joanna J. , Piek Jan J. , Garg Scot , Hamm Christian , Steg Gabriel , Vranckx Pascal , Valgimigli Marco , Windecker Stephan , Juni Peter , Onuma Yoshinobu , Steyerberg Ewout , Xu Bo , Serruys Patrick W. 
Published: February 2021

AbstractAimsWe aimed to update the logistic clinical SYNTAX score to predict 2 year all‐cause mortality after contemporary percutaneous coronary intervention (PCI).Methods and resultsWe analyzed 15,883 patients in the GLOBAL LEADERS study who underwent PCI. The logistic clinical SYNTAX model was updated after imputing missing values by refitting the original model (refitted original model) and fitting an extended new model (new model, with, selection based on the Akaike Information Criterion). External validation was performed in 10,100 patients having PCI at Fu Wai hospital.Chronic obstructive pulmonary disease, prior stroke, current smoker, hemoglobin level, and white blood cell count were identified as additional independent predictors of 2 year all‐cause mortality and included into the new model.The c‐indexes of the original, refitted original and the new model in the derivation cohort were 0.74 (95% CI 0.72–0.76), 0.75 (95% CI 0.73–0.77), and 0.78 (95% CI 0.76–0.80), respectively. The c‐index of the new model was lower in the validation cohort than in the derivation cohort, but still showed improved discriminative ability of the newly developed model (0.72; 95% CI 0.67–0.77) compared to the refitted original model (0.69; 95% CI 0.64–0.74). The models overestimated the observed 2 year all‐cause mortality of 1.11% in the Chinese external validation cohort by 0.54 percentage points, indicating the need for calibration of the model to the Chinese patient population.ConclusionsThe new model of the logistic clinical SYNTAX score better predicts 2 year all‐cause mortality after PCI than the original model. The new model could guide clinical decision making by risk stratifying patients undergoing PCI.
Shape Selectivity of a Metallo Cavitand Host Allows Separation of n‐Alkanes from Isooctane
Authors: Wan Yun‐Hui , Rahman Faiz‐Ur , Rebek Julius , Yu Yang 
Published: February 2021

Main observation and conclusionThe use of a metallo cavitand for the selective sequestration of n‐alkanes from their mixtures with isooctane is described. Competition experiments and NMR spectroscopy are used to show the preference of a water‐soluble cavitand host for guests that are hydrophobic and have narrow or flat shapes. The host showed selectivity for trans 1,4‐dimethylcyclohexane over the cis‐isomers. The separations of n‐alkanes from isooctane by gas/liquid adsorption and a liquid/liquid extraction are detailed.
Positional Electronic Effects in Iminopyridine‐N‐oxide Nickel Catalyzed Ethylene Polymerization†
Authors: Chi Mingjun , Chen Ao , Pang Wenmin , Tan Chen , Chen Changle 
Published: February 2021

Main observation and conclusionA series of dibenzhydryl‐based iminopyridine‐N‐oxide ligands bearing a range of electron‐donating or ‐withdrawing substituents (OMe, H, and NO2) and corresponding nickel pre‐catalysts are prepared and characterized. The substituents are installed at different positions on the ligand structure, including 4‐position of the pyridine‐N‐oxide moiety (position X) and 4‐position of the aniline moiety (position Y). These nickel pre‐catalysts are highly active in ethylene polymerization with the addition of very little amount of aluminum cocatalysts, leading to the formation of polyethylenes with molecular weights of well above one million. Electron‐donating substituents make the catalysts sensitive to polymerization temperature. In contrast, the catalysts bearing electron‐withdrawing NO2 substituents show relatively steady performances at different temperatures. Most importantly, we demonstrate that different substituents and different positions both play important roles in determining the properties of nickel catalysts. This provides an alternative strategy for the future design of high‐performance polymerization catalyst.
Selective Recognition of Quaternary Ammonium Ions by Structurally Flexible Cages†
Authors: Huang Qi‐Cheng , Quan Mao , Yao Huan , Yang Liu‐Pan , Jiang Wei 
Published: February 2021

Main observation and conclusionThe binding behaviors of three structurally similar and flexible cages to a series of quaternary ammonium ions have been systematically studied. The cage with phenyl sidewalls is new; moreover, its structure and conformational states have been characterized by NMR, 2D NMR, and X‐ray crystallography. The results reveal that the three cages show quite high binding affinities and selectivities to different guests. Enthalpy‐entropy compensation was invoked to explain the different binding performance. Moreover, a six‐component, high‐fidelity self‐sorting system was successfully constructed by using these cages and three guests. This suggests that conformationally flexible hosts may also achieve high binding affinities and selectivities, which is in contrast to the traditional point of view — only preorganized and rigid hosts are able to do so. This research advocates that conformational flexibility should also be seriously considered in host design.