bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of Fault Location in Distribution Networks Using Multi Class Support Vector Machines
Authors: Agrawal Rimjhim , Dhadbanjan Thukaram
Published: September 2012

This paper presents a multi-class support vector machine (SVMs) approach for locating and diagnosing faults in electric power distribution feeders. Different from the traditional Fault Section Estimation methods, the proposed approach uses measurements available at the substation and remote terminal units (RTUs). To show the effectiveness of the proposed methodology, a practical 52 nodes, 3 feeder distribution systems (DS) with loads is considered. Practical situations in distribution systems, such as protective devices (circuit breakers/isolators) placed at different locations and all types of faults with a wide range of varying source short circuit (SSC) levels and fault impedances are considered for studies. The proposed fault location scheme is capable of accurately identify the fault type, location of faulted feeder section and the fault impedance. The results demonstrate the feasibility of applying the proposed method in practical distribution automation (DA) system for fault diagnosis.
Optimization of Microwave Assisted Extraction Conditions for Total Flavonoids in Toona Sinensis Leaves Using Response Surface Methodology
Authors: Wang Changlu , Li Zhenjing , Li Fengjuan , Chen Mianhua , Wang Yurong , Li Yadi , He Dong
Published: September 2012

In this study Microwave assisted extraction (MAE) was employed to extract total flavonoids (TF) from the Toona sinensis leaves (TSL). Single factor experiments to evaluate the effects of the process parameters (extraction duration, solvent-solid ratio, ethanol volume fraction, and extraction times) on TF yield of TSL was performed, and response surface methodology (RSM) were used to optimize the extraction parameters. The analysis of variance indicated that the linear coefficients extraction duration, the quadratic terms of extraction duration and solvent-solid ratio, had highly significant effects on the TF yield (P<0.01). And, the quadratic terms of ethanol volume fraction had significant effects on the TF yield (P<0.05). The optimal conditions to obtain the maximum TF yield from TSL were extraction duration 85s, solvent-solid ratio (v/w, mL/g) 20, ethanol volume fraction 50%, microwave power 700 W, and repeated extraction two times. Under these optimal conditions, the TF yield was up to 2.39%. The analysis of variance (ANOVA) and validation test indicated that the method is useful and reliable.
Thermal Properties of Polyurethane Films Prepared from Mixed Cellulose, Hemicelluloses and Lignin
Authors: Shao Meng , Liu Zhu-qing , Li Dong , Zhao Yang , Özkan Necati , Chen Xiao Dong
Published: September 2012

Polyurethane (PU) films were prepared from liquefied cellulose, hemicelluloses and lignin in different proportions. The simplex-lattice design method was employed to investigate the effects of each component and their associated interactive effects on the properties of the liquefied products and the PU films. Thermal properties were studied by means of Dynamic Mechanical Analyzer (DMA) and Thermal Gravimetry Analyzer (TGA). Results showed that the contents of cellulose, hemicelluloses and lignin significantly affected the thermal properties of PU films. The results of DMA suggested that the addition of the liquefied materials increased the glass transition temperature (Tg) of polyurethane (PU) films but decreased both storage modulus (E') and loss modulus (E''). TGA results indicated that the addition of the liquefied materials decreased the thermal stabilities of the PU films.
A characterization of multiple (n – k)-blocking sets in projective spaces of square order
Authors: Ferret S. , Storme L. , Sziklai P. , Weiner Zs.
Published: September 2012

In [10], it was shown that small t-fold (n - k)-blocking sets in PG(n; q), q = ph, p prime, h ≥ 1, intersect every k-dimensional space in t (mod p) points. We characterize in this article all t-fold (n - k)-blocking sets in PG(n,q), q square, q ≥ 661, t<cp q1/6 /2 |B|<tqn-k +2tqn-k-1 √q intersecting every k-dimensional space in t (mod √q ) points.
Metal-dielectric composite optical coatings: underlying physics, main models, characterization, design and application aspects
Authors: Stenzel Olaf , Macleod Angus
Published: September 2012

Metal island films are a matter of research in different branches of applied physics and technology. One possible future application field is their use as a substantial part of optical interference coatings, forming metal-dielectric composite multilayer coatings. This tutorial provides background on optical specifics of metal island films and ideas how these specifics could be exploited in coating technology. Consideration is given to effective optical constants of copper and silver island films, characterization methods and design strategies pursuing neutral density filters, asymmetric beamsplitters and decorative coating specifications.
Review of computational lithography modeling: focusing on extending optical lithography and design-technology co-optimization
Authors: Lai Kafai
Published: September 2012

Advances in computational lithography over the last 10 years have been instrumental to the continued scaling of semiconductor devices. Competitive scaling requires two types of complementary models: fast predictive empirical models that can be used for pattern correction and verification; rigorous physical models that can be used to identify key physical effects that must be considered to ensure pattern fidelity, but are too resource intensive to use for full chip applications. Today, all computational lithography efforts such as the optical proximity correction (OPC) and the optical rules check (ORC) depend on the ability to predictively model the lithography and metrology processes. We discuss some of the current modeling practices in optics, mask, resist and etching, leading to the “Holy Grail” of predictively modeling entire patterning process which we call “virtual fab”. Extreme ultraviolet (EUV) modeling is discussed due to its potential to extend optical lithography scaling for future nodes. Modeling of novel technologies such as Diblock Copolymer patterning is also discussed to demonstrate new opportunities for continued scaling. Complexity of the “virtual fab” approach is extremely high as there are multiple dimensions in this approach. The need to overcome this complexity, by reducing the number of dimensions of the problem, is evident. Lastly, the ability to leverage lithography modeling in design co-optimization is an important element of semiconductor device scaling.
From transcription to translation: new insights in the structure and function of Argonaute protein
Authors: Giorgi Corinna , Cogoni Carlo , Catalanotto Caterina
Published: September 2012

Argonaute proteins play a central role in gene silencing pathways mediated by small RNA molecules. The ancestral function of small RNA-dependent silencing is related to genome protection against parasitic nucleic acids, such as transposons and viruses. However, new classes of small RNAs are continuously being uncovered in all higher eukaryotes in which they play important functions in processes ranging from embryonic development to differentiation to cell proliferation and metabolism. Small RNAs have variegated biogenesis pathways and accomplish distinct functions. Nevertheless, it appears that all small RNAs work merely as guides in recognizing the target RNAs invariably relying on the interaction with Argonaute proteins and associated factors for their biological function. Here, we discuss recent findings on the structure and regulation of mammalian Argonaute proteins and overview the various roles that these versatile proteins play in regulating gene expression.
Hormone-autonomous cell culture from cotydelonary tissue of the marine plant Cymodocea nodosa
Authors: Elso Maite Zarranz , González-Henríquez Nieves , García-Jiménez Pilar , Robaina Rafael R.
Published: September 2012

In vitro germinated seedlings of ­Cymodocea nodosa were used as a source of young embryonic tissue for cell culture. Histological study of the cotyledon revealed the presence of meristematic tissue that gave rise to the first leaf of the plantlet, which released large numbers of cells after enzymatic digestion and thus indicated great growth potential. An effective enzymatic digestion protocol for C. nodosa meristem tissue was developed; this consisted of a 24-h digestion period at 28°C using a 0.6-m enzymatic solution (plasmolysis medium containing 1% (w:v) cellulase and hemicellulase). It was necessary to add citric acid (0.02 m) as an antioxidant to the enzymatic solution to obtain the highest cell yield and viability (mean±SE: 371.6±30.1×105 cells g-1 fw and 97.8±0.6%, respectively). NaCl and other salt components of the seawater were key factors in the establishment of axenic cell cultures and their further progress; their absence in the medium inhibited contaminant overgrowth. Nevertheless, cells maintained growth for 90 days, even without hormones and deprived of salts, although these salts might be necessary to allow the development of morphogenetic programmes desired for plant production. In this manner, we generated a basic tool for the future of C. nodosa in vitro culture that will allow the establishment and maintenance of hormone-autonomous cell cultures with strong potential in future biotechnology for marine higher plants.
An efficient synthesis of 2-substituted benzoxazoles using cerium(III) chloride/sodium iodide as catalyst
Authors: Zhu Xun , Wei Yunyang
Published: September 2012

An efficient and environmentally benign method for the synthesis of 2-substituted benzoxazoles is reported. The condensation of 2-aminophenol with an aldehyde gave an imine intermediate, which was cyclized and dehydrogenated to 2-substituted benzoxazole with good yield in the presence of CeCl3/NaI as catalyst. The one-pot synthesis was carried out in toluene at 100°C using O2 as the oxidant.
Synthesis of perhydro-N-(2,2-disubstituted-3-aminopropyl) heterocycles as potentially bioactive compounds and fragments for combinatorial chemistry
Authors: Hayotsyan Sargis S. , Mkryan Gevorg G. , Aghekyan Asya A. , Melikyan Gagik S.
Published: September 2012

A new method for the preparation of perhydro-­N-(2,2-disubstituted-3-aminopropyl) heterocycles that allows to obtain a large variety of corresponding derivatives with high to moderate yields using simple procedures is described.
Enzymatic bleaching of eucalyptus kraft pulp: effects on the prebleaching filtrate, pulp quality and paper properties
Authors: Borges Maria Tereza , Silva Claudio Mudado , Colodette Jorge Luiz , de Oliveira Rubens Chaves , Tesser Flavio
Published: September 2012

Enzymatic bleaching appears to be a promising approach for clean bleaching processes and the reduction of bleaching chemical consumption. In this work, the quality of the filtrates and the pulps has been characterized after enzymatic prebleaching stages of eucalyptus kraft pulp. Four different conditions with xylanase were investigated. Following each prebleaching stage, the properties of the pulp [kappa number, brightness, content of hexenuronic acid (HexA), xylan removal, and pulp yield lost], and of the resulting effluents (chemical oxygen demand (COD), biochemical oxygen demand (BOD), color, and conductivity) were determined. In addition, a complete bleaching sequence was performed to characterize the pulp quality at the end of the sequence. Finally, the pulp was refined in a PFI mill, and the mechanical and physical properties of the resulting paper were determined. The best pulp quality was achieved at pH 7, at which a lower kappa number, higher pulp brightness, and smaller amount of HexA were observed. Under this condition, however, a larger yield loss and a higher effluent COD load had to be accepted. After the complete bleaching sequence, the enzymatic treatments yielded pulps with higher brightness and viscosity as well as with a lower kappa number. The enzymatic treatments resulted in small changes in the mechanical and physical properties of the paper handsheets produced.
Climate response of cell characteristics in tree rings of Picea crassifolia
Authors: Xu Jinmei , Lu Jianxiong , Bao Fucheng , Evans Robert , Downes Geoffrey M.
Published: September 2012

Dimensions of dated tree rings are an important tool of dendroclimatology. However, the relationships between climatic variables and cell diameter and cell wall thickness are not yet clearly elaborated. In the present article, year-to-year cell characteristics, ring width, and wood density of Picea crassifolia trees growing in northwestern China have been measured with high resolution by means of the instrument SilviScan-3. The response function analysis showed that climate explained 51% of the variation of cell radial diameter chronology, 48% of wood density, 40% of cell wall thickness, and 37% of ring width. Cell wall thickness and wood density responded significantly and positively to temperature, and the response to precipitation was negative, while the opposite was true for cell radial diameter and ring width. Cell wall thickness and wood density were pronounced (statistically significant) to temperature in September and precipitation in May and August. Cell radial diameter responded significantly to temperature in June and July, and precipitation, in August. For ring width, the temperature in July was important. Accordingly, cell characteristics are sensitive to climate, and the findings could be useful in the field of dendroclimatology.
Compressive-torsion DMA of yellow-poplar wood in organic media
Authors: Chowdhury Sudip , Frazier Charles E.
Published: September 2012

This work continues the introduction of the dynamic mechanical analysis (DMA) of wood in a novel stress mode, compressive-torsion. The glass/rubber transition in yellow-poplar (Liriodendron tulipifera) wood was measured under saturation in four organic solvents: N,N-dimethylformamide (DMF), N-methylpyrrolidone (NMP), ethylene glycol, and glycerol. Systematic measurement of the linear viscoelastic response (LVR) revealed a complex relationship of LVR with grain orientation, temperature and solvent. This indicates that special care is required when analysis within the LVR is critical. Glass transition temperatures (Tgs) of swollen wood showed an inverse relationship with solvent induced volumetric swelling. DMF and NMP both caused volumetric swelling of ≥25%, and the corresponding Tgs were near 50°C. Ethylene glycol and glycerol caused volumetric swelling <25% and the corresponding Tgs were ≥100°C. Glycerol showed significantly higher solvolytic power than ethylene glycol. Glycerol plasticized wood underwent irreversible swelling when heated beyond the Tg, causing a reduction in the effective crosslink density and in the Tg. Consistent with the literature, the observed Tg grain dependency was highly varied. The weakest plasticizer, glycerol, produced a prominent Tg grain dependency, whereas grain dependency was variable in the stronger swelling agents. This study demonstrates the importance of researching lignocellulose rheology in a greater variety of organic liquids, to achieve new perspectives into the structure/property relationships of lignocellulose, and aspects of processing in organic media.
Measurement of intra-ring wood density by means of imaging VIS/NIR spectroscopy (hyperspectral imaging)
Authors: Fernandes Armando , Lousada José , Morais José , Xavier José , Pereira João , Melo-Pinto Pedro
Published: September 2012

This paper reports a novel application of hyperspectral imaging (a spectroscopic technique) for measuring wood density profiles at the growth ring scale. The measurements were performed with a spatial resolution of 79 µm. In the present case, hyperspectral imaging was used to measure wood sample reflectance for light in the wavelength range between 380 and 1028 nm, with a resolution of approximately 0.6 nm. The work was performed with 34 samples collected from 34 trees of Pinus pinea. A total of 34,093 density points were used to create and validate a partial least-squares (PLS) regression that converts spectroscopic reflectance data into density values. The coefficient of determination value between the present method and X-ray microdensitometry is 0.810 with a root mean squared error of 6.54×10-2 g.cm-3.
Convenient preparation of a β-O-4-type lignin model trimer via KOH-catalyzed hydroxymethylation and a new protection method
Authors: Lahtinen Maarit , Haikarainen Anssi , Sipilä Jussi
Published: September 2012

Lignin, as the second most abundant biopolymer on earth, is one of the targets for plant biorefinery studies. Its complex chemical behavior is frequently studied by dimeric, trimeric, etc. model compounds, preferably with a β-O-4-type structure. In the present study, a convenient synthesis of a β-O-4-type trimeric model compound possessing a free syringylic hydroxyl has been investigated. Two key modifications were in focus: (1) Protection of the aliphatic hydroxyl groups of the starting phenolic dimer prior to the SN2 displacement reaction before introducing the syringylic moiety with 2,2-dimethoxypropane. (2) The hydroxymethylation step to introduce the full side chain moiety. When this reaction was performed in dioxane/water in the presence of a catalytic amount of KOH instead of K2CO3, the formation of a side product via dehydration was markedly reduced. In addition, a convenient method for introducing an α,β-epoxide structure in acetophenone is recommended.
Topochemistry of heat-treated and N-methylol melamine-modified wood of koto (Pterygota macrocarpa K. Schum.) and limba (Terminalia superba Engl. et. Diels)
Authors: Mahnert Karl-Christian , Adamopoulos Stergios , Koch Gerald , Militz Holger
Published: September 2012

To broaden the knowledge about the chemical changes at the cell wall level of differently modified tropical hardwoods, heat-treated and N-methylol melamine (NMM)-treated samples of koto (Pterygota macrocarpa) and limba (Terminalia superba) were prepared. UV microspectrophotometry (UMSP) was applied at 278 and 240 nm as specific wavelengths to analyze chemical alterations of the samples caused by heat and NMM treatment, respectively. The absorbance of koto exceeded that of limba before and after treatment, potentially due to the higher extractive content of the former. Regardless of the wood species, the absorbance of the samples increased with increasing intensity of the NMM treatment. Additionally, the absorbance of lignin within the spectrum of 230–350 nm was altered due to the NMM treatment. The functionality of applying specific wavelengths for the analysis of different modification methods of wood was proven. However, the comparison with literature did not show differences in the absorbance, which could be assigned to the characteristics of tropical hardwoods.
Behavior of xylans from Eucalyptus species. Part 1. The influence of structural features of eucalyptus xylans on their retention in kraft pulp
Authors: Magaton Andréia S. , Silva Teresa Cristina F. , Colodette Jorge Luiz , Piló-Veloso Dorila , Milagres Flaviana Reis
Published: September 2012

4-O-methylglucuronoxylans were isolated from the wood and pulp of different Eucalyptus species (E. dunni, E. grandis, E. nitens, E. urograndis and E. urophylla) and characterized by 1H NMR spectroscopy and size-exclusion chromatography (SEC). The content of 4-O-methylglucuronic acid (MeGlcA) varied between the eucalyptus species from 1.90 to 2.80 expressed as MeGlcA/10 xyloses, whereas in the pulp, the total uronic acid content was approximately 1.02, from which the half was hexenuronic acid (HexA). From the MeGlcA linked to the xylan chain 9–26% are substituted in position O-2 by hexose units. The Mw of the xylans extracted from wood ranged between 26.1 and 28.4 kDa. The retention of 4-O-methylglucuronoxylans (51.3–58.7%) during kraft pulping was high, and the retention is related to the content of MeGlcA group, the content of MeGlcA group substituted at O-2, and the average molecular weight of the xylans. The parameters observed affect the overall pulp yield and pulp properties.
Fractal dimension analysis of void size in wood-strand composites based on X-ray computer tomography images
Authors: Li Peng , Wu Qinglin , Tao Yubo
Published: September 2012

Oriented strandboards were constructed from various combinations of mixed hardwood flakes. Fractal dimension of void size (FDVS) in the manufactured samples was studied by means of X-ray computer tomography images and a computer image processing technique. The FDVS value was high in the panel surface layers and decreased toward the panel center, and the FDVS decrement was linear to increased porosity. At the same overall porosity level, the FDVS varied as function of void distribution. FDVS could be a useful additional parameter for characterizing the internal void structure of strand-based wood composites.
A fast multiscale Galerkin method for ill-posed integral equations with not
exactly given input data via Tikhonov regularization
Authors: Luo Xingjun , Yang Xu , Huang Xiantong , Li Fanchun
Published: September 2012

In this paper we develop a fast
multiscale Galerkin method solving ill-posed integral equations with not
exactly given input data
via Tikhonov regularization. The method leads to fast
solutions of discrete Tikhonov regularization. The
convergence rates of the Tikhonov regularization are achieved
by using a modified discrepancy principle. Finally, numerical
experiments are given to illustrate the efficiency of the method.
On some identification problem for source function to one semievolutionary system
Authors: Belov Yuri Y. , Kopylova Vera G.
Published: September 2012

We solve an identification problem for source functions to one-dimensional second order parabolic-elliptic system. Considered the system of equations obtained from the original system, where the time derivative added to the elliptic equation, containing a small parameter , we prove the following: the solvability “in general” of the inverse problem for , uniqueness of classical solutions of the inverse problem, periodicity of the spatial variable solutions of approximating problems for , a priori (uniform in ) estimates of solutions of approximating problems, convergence on the basis of the a priori estimates of solutions approximating the inverse problems to solutions original for , the rate of convergence (order ) of solutions of approximating problems in classes of continuous functions. An identification problem of source functions in the system of composite type is treated by some authors. The case where the unknown component of the vector source function in the equation that does not contain the small parameter was studied by Belov (2010).
A practical method for reducing blindness due to retinopathy of prematurity in a developing country
Authors: Gordillo Luz , Villanueva Ana Maria , Quinn Graham E.
Published: September 2012

Background: Retinopathy of prematurity (ROP) is a common cause of blindness in countries with rapidly developing systems of neonatal care. At present, detection and treatment programs are not widely available in many regions of middle- and low-income countries.

Subject population: Case series.

Methods: An analysis was undertaken to determine in which neonatal intensive care units (NICUs) in Peru babies blind from ROP had been cared for. Demographic and hospital information was gathered for children blind from ROP presenting before the age of 5 years. NICUs with a high likelihood of having ROP-blind children were offered training and equipment designed to improve neonatal care.

Results: Ninety-one children with ROP blindness were identified. Twenty-six percent were <1000 g at birth, and 17% had birth weights of >1500 g. Forty-six percent came from NICUs in Lima. Interventional workshops emphasizing neonatal care and oxygen administration have been conducted thus far in six of the 13 largest NICUs in Lima. The percentage of at-risk babies being examined has generally increased, whereas the percentage of babies requiring treatment decreased in three NICUs and increased slightly in two, and no preworkshop data were available in one.

Conclusion: This report represents the initial results of an evidence-based approach to decreasing blindness from ROP in Peru. Workshops emphasizing neonatal care, especially targeting oxygen administration, provide methods for improving care of at-risk babies.
Intravenous iron treatment in pregnancy: comparison of high-dose ferric carboxymaltose vs. iron sucrose
Authors: Christoph Patricia , Schuller Christine , Studer Hanna , Irion Olivier , De Tejada Begoña Martinez , Surbek Daniel
Published: September 2012

Objective: Oral iron substitution has shown to be insufficient for treatment of severe iron deficiency anemia in pregnancy. Ferric carboxymaltose is a new intravenous (i.v.) iron formulation promising to be more effective and as safe as iron sucrose. We aimed to assess side effects and tolerance of ferric carboxymaltose compared to i.v. iron sucrose in pregnant women.

Methods: We performed a retrospective analysis of 206 pregnant women who were treated either with ferric carboxymaltose or iron sucrose for iron-deficiency anemia with intolerability to oral iron substitution, or insufficient hemoglobin increase after oral iron treatment, or need for rapid hemoglobin reconstitution. Primary endpoint was to evaluate the maternal safety and tolerability. Secondary endpoint was to assess efficacy of the treatment and exclude safety concerns for the fetus.

Results: The incidence of drug-related adverse events was low and mostly mild in both groups. Mild adverse events occurred in 7.8% for ferric carboxymaltose and in 10.7% for iron sucrose. The mean rise of hemoglobin value was 15.4 g/L for ferric carboxymaltose and 11.7 g/L for iron sucrose.

Conclusion: Ferric carboxymaltose administration in pregnant women is well tolerated and is not associated with any relevant clinical safety concerns. Ferric carboxymaltose has a comparable safety profile to iron sucrose but offers the advantage of a much higher iron dosage at a time reducing the need for repeated applications and increasing patients’ comfort. Ferric carboxymaltose is the drug of choice, if i.v. iron treatment becomes necessary in the second or third trimester of pregnancy.
Can discordance in CRL at the first trimester predict birth weight discordance in twin pregnancies?
Authors: Weissmann-Brenner Alina , Weisz Boaz , Achiron Reuven , Shrim Alon
Published: September 2012

Objective: To examine the correlation between measurements of crown rump length (CRL), nuchal translucency (NT), and birth weight in dichorionic (DC) and monochorionic (MC) twin pregnancies.

Methods: A retrospective analysis was performed on all twin term pregnancies delivered between 2001 and 2007 at the McGill University Health Center. Data collected included maternal age, CRL and NT measurement, results of glucose challenge test, birth weight and length, gestational age at delivery, and fetal gender.

Results: The study population comprised 792 fetuses: 94 MC/DA and 698 DC/DA. Maternal age, gestational age at delivery, birth weight, and birth length were all significantly higher for the DC group. Male fetuses had significantly higher NT and higher birth weight than female fetuses. Discordance in CRL was found to correlate with discordance in birth weight in the entire study population (P<0.0001, R=0.25), in the DC twins (P<0.0001, R=0.275), but not in MC twins (R=0.10, P=0.33). CRL discordance above the 90th percentile (>12%) predicted 14/40 pregnancies with birth weight discordance above the 90th percentile (>24%) [P<0.001, LR=4.1 (2.6–6.2)]. CRL discordance above the 95th percentile (>16%) predicted 5/21 pregnancies with birth weight discordance above the 95th percentile (>30%) [P<0.001, LR=5.5 (2.6–10.4)]. NT discordance was correlated with CRL discordance (R=0.15, P<0.0001), but not with birth weight, regardless of chorionicity or gender.

Conclusion: In twin pregnancies, CRL discordance in first trimester can predict discordance of more than 25% in neonatal birth weight.
Central-peripheral temperature gradient: an early diagnostic sign of late-onset neonatal sepsis in very low birth weight infants
Authors: Leante-Castellanos José Luis , Lloreda-García José M. , García-González Ana , Llopis-Baño Caridad , Fuentes-Gutiérrez Carmen , Alonso-Gallego José Ángel , Martínez-Gimeno Antonio
Published: September 2012

Aims: We assessed central-peripheral temperature gradient alteration for the diagnosis of late-onset neonatal sepsis and compared earliness detection of this sign with altered blood cell count and C-reactive protein.

Method: Thirty-one preterm babies (<1500 g or <32 weeks) participated in an observational prospective study. Axillary (central) and sole (peripheral) temperatures were continuously monitored with a thermal probe (ThermoTracer; Dräger Medical AGF & Co. KgaA, Lübeck, Germany) adjusting incubator air temperature for a thermal gradient <1.5°C. Central-peripheral temperature alteration was defined as a thermal gradient >2°C that could not be corrected with protocolized air temperature modifications. Proven (positive blood culture) sepsis and probable late-onset sepsis were recorded.

Results: Late-onset sepsis was diagnosed in 11 neonates (proven, 9; probable, 2). Thermal gradient alteration was present in 12 cases, in association with the onset of sepsis in 10 and concomitantly with a ductus arteriosus and stage 1 necrotizing enterocolitis in 2. Thermal gradient alteration had a sensitivity of 90.9% [95% confidence interval (CI), 62.3–98.4] and specificity of 90% (95% CI, 69.9–97.2%), and in 80% of cases, it occurred before abnormal laboratory findings.

Conclusions: Central-peripheral temperature gradient monitoring is a feasible, non-invasive, and simple tool easily applicable in daily practice. An increase of >2°C showed a high-sensitivity and specificity for the diagnosis of late-onset sepsis.
Rapid neonatal weight gain increases risk of childhood overweight in offspring of diabetic mothers
Authors: Plagemann Andreas , Harder Thomas , Rodekamp Elke , Kohlhoff Rainer
Published: September 2012

Aim: Increased neonatal weight gain has been suggested as risk factor for later overweight. Offspring of diabetic mothers (ODM) have a long-term increased overweight risk. However, the role of early postnatal weight gain for later overweight has not been addressed so far in ODM. We investigated whether increased weight gain during the first 4 months is related to later overweight in ODM.

Methods: Determinants of childhood overweight and neonatal weight gain were analyzed in 152 ODM from the Kaulsdorf Cohort Study by MANOVA and regression analyses.

Results: Independent of birth weight, weight gain during the first 4 months was positively related to childhood relative body weight (P=0.001). Each 100 g-increase in weight during this period increased overweight risk by 65% (95%CI: 10–247%). ODM with rapid early weight gain had a more than six-fold increased risk of later overweight (OR: 6.77; 95%CI: 1.36–33.6). Early neonatal intake of breast milk from metabolically healthy mothers protected from rapid early weight gain (P=0.03).

Conclusions: Increased weight gain during the first 4 months of life is a strong, independent risk factor for childhood overweight in ODM. Preventing nutritionally-induced rapid early weight gain in ODM might be a promising strategy to lower their long-term overweight risk.
Induction of labor after a prior cesarean delivery: lessons from a population-based study
Authors: Shatz Lea , Novack Lena , Mazor Moshe , Weisel Ruthy Beer , Dukler Doron , Rafaeli-Yehudai Tal , Israeli Osnat , Erez Offer
Published: September 2012

Objectives: The aims of this study were (1) to determine the success rate of induction of labor (IOL) in women with a prior cesarean section (CS) and (2) to compare the perinatal outcome of a trial of labor (TOL) in women with one prior CS who had an IOL, spontaneous onset of labor, or an elective repeated CS (ERCS).

Material and methods: This study population was divided into three groups: women who had (1) ERCS (n=1916), (2) spontaneous TOL (n=4263), and (3) IOL (n=1576).

Results: (1) The rate of IOL in the study cohort was 20.3%; of these, 67.4% had a successful vaginal birth after cesarean (VBAC). (2) Patients in the spontaneous TOL group had a higher VBAC rate than did those who had IOL (P<0.001). (3) The rate of uterine rupture was comparable among all study groups. And (4) a prior vaginal birth increased the likelihood of having a successful induction and a VBAC by 50%.

Conclusion: IOL in patients with a previous CS is successful in about two-thirds of the cases. Induction is a safe and useful tool that can serve as an alternative for ERCS and assist to reduce the rate of ERCS.
A special comment from the Founder of the Journal of Perinatal Medicine on the occasion of the 40th anniversary of its existence
Authors: Saling Erich
Published: September 2012

No abstract available.
Estimation of thermal conductivity of PP/Al(OH)3/Mg(OH)2 composites
Authors: Liang Ji-Zhao
Published: September 2012

The thermal conductivity of polypropylene (PP) composites filled with Al(OH)3 and Mg(OH)2 was measured by means of the stable flat measuring instrument at different testing temperatures. The effective thermal conductivity of the composites was estimated by applying the thermal conductivity equation proposed previously, and the estimations were compared with the experimental measured data under the same experimental conditions. The results showed that the calculations and measurements of the effective thermal conductivity were close to each other when the volume fraction of the Al(OH)3/Mg(OH)2 powder was <10.4%. Moreover, the effective thermal conductivity of the composites was estimated using the Russell model and the Maxwell-Eucken model, and the predictions were compared with the experimental data and the estimations of this equation. It was found that the estimations of this equation were closer to the experimental data than those of the Russell model and Maxwell-Eucken model.
Influence of hydrostatic pressure and volumetric strain on the mechanical long term behavior of polymers
Authors: Naumann Tobias , Stommel Markus
Published: September 2012

One of the most crucial issues in developing a material model to describe the long term behaviour of polymers is to represent adequately the load dependency of the considered material. In many publications, it is shown that the free volume affects the mechanical behavior of polymers. For a further investigation of the dependency of the creep behavior on free volume, different experiments are presented in this paper. In one experiment, the creep behavior under tension and shear are compared, to see how the different hydrostatic pressures in these tests influence mechanical behavior. Furthermore, tensile creep tests under different hydrostatic pressures are conducted experimentally. The experiments are conducted on a polycarbonate, a polypropylene and a polymethyl methacrylate. It is shown that the hydrostatic pressure has a significant influence on the creep behavior of all three materials. This effect is related to the change of free volume.
Investigation of the processing, the mechanical properties, and the morphology of short glass fiber-reinforced polypropylene-layered silicate composites
Authors: Hopmann Christian , Michaeli Walter , Puch Florian
Published: September 2012

Polypropylene composites containing layered silicate and glass fibers are prepared by melt compounding. To investigate the influence of the processing conditions on the mechanical properties and the morphology of short glass fiber-reinforced polypropylene-layered silicate composites, the process parameters are varied while preparing the composites. The processing conditions affect the mechanical properties and the morphology. The investigations suggest that a short glass fiber-reinforced polypropylene-layered silicate composite should be compounded at a maximum barrel temperature of 200°C, a throughput of 30 kg/h at a screw speed of 500 min-1 and a screw configuration, which introduces a large amount of shear energy into the composite. These processing conditions lead to a comparatively high specific mechanical energy input of 206 Wh/kg and to the best set of mechanical properties of the investigated materials. However, the morphology of the investigated short glass fiber-reinforced nanocomposites does not show significant differences and has to be investigated further.
Surface properties of the in situ formed ceramic-reinforced composite coating on TA15 alloy
Authors: Wei Li , Shaofu Shan , Qianghan Fang
Published: September 2012

A hard composite coating was fabricated by laser alloying of the Co-Fe-Al+B4C-Si3N4 mixed powders on TA15 (Ti-6Al-2Zr-1Mo-1V) titanium alloy in an open system. The composite coating mainly consisted of γ-Co, TiB2, TiB, TiC0.3N0.7, SiC, Ti3Al, FeAl, and Co-Ti intermetallics. The TEM diffraction pattern results indicated that the orientation relationship between TiB2 and TiC0.3N0.7 was (1-20)TiB2//(2-20)TiC0.3N0.7 in such a coating. Furthermore, during the alloying process, a number of Mo and Zr entered into the molten pool from the substrate due to the dilution effect, which refined the microstructures of the composite coating and also increased the amorphous phase content.
Polyethylene Oxide-Polystyrene Oxide Triblock Copolymers as Biological-Responsive Nanocarriers.
Authors: Cambón Adriana , Rey-Rico Ana , Barbosa Silvia , Brea Jose , Loza M. I. , Yeates Stephen G. , Alvarez-Lorenzo Carmen , Concheiro Angel , Taboada Pablo , Mosquera Victor
Published: September 2012

The present work presents the synthesis, characterization and evaluation of the biocompatibility and ability to dissolve and chemically protect the anticancer drug doxorubicin (DOXO) of two polyethylene oxide-polystyrene oxide triblock copolymers, EO33SO13EO33 and EO38SO10EO38, where EO and SO denote the ethylene oxide and styrene oxide blocks, respectively. Block copolymer length and SO/EO ratio were selected with the objective of ensuring an optimal compromise between chain solubility, micelle formation ability and core size for enhanced drug solubilization. The temporal stability of the drug-loaded micelles and drug release profile were also analyzed as well as their efficacy as an antitumoral polymeric formulation in vitro by using a multidrug resistant ovarian tumor cell line (NCI-ADR-RES), with the special aim of analyzing the possible capability of both copolymers as potential P-glycoprotein efflux (P-gp) pump inhibitors to enhance DOXO accumulation in this cell line.
Effect of Orientation and Microstructure on the Magnetic Anisotropy of Co/Pd Multilayers
Authors: Broeder Frits J. A. den , Kuiper Dick , Hoving Willem
Published: September 2012

Co/Pd multilayers containing one to eight atomic layers of cobalt and ten atomic layers of palladium per modulation period were prepared in two orienotarteiottnoss, [111]fcc and [001]fcc. The [111] films were polycrystalline, the [001] films were epitaxial.

In this paper we compare the magnetic anisotropy of both types of films, which can be described by an interface anisotropy contribution favouring perpendicular magnetization and a volume contribution favouring in-plane magnetization. Depending on the deposition temperature, a perpendicular anisotropy for [111] films is found for up to about six atomic layers of Co. The [001] films however, show perpendicular anisotropy only for Co monolayers or Co bilayers. The large difference between the anisotropies in the two orientations is mainly caused by a strong in-plane anisotropy volume term which exists for [001] films, and which is attributed to the structural deformation of the Co layers from cubic to tetragonal. For both orientations a higher deposition temperature is found to lead to an increase of the interface anisotropy due to smoothing of the layers.
Fe-Ag Superlattices by Molecular Beam Epitaxy
Authors: Mayer S. H. , Gutierrez C. J. , Walker J. C.
Published: September 2012

We have succeeded in producing high quality (110)Fe/(111)Ag superlattices by Molecular Beam Epitaxy. Important parameters in the production of these materials were substrate temperature and effusion rates of the constituents. We have used SQUID magnetometry, Mössbauer spectroscopy and Reflection High Energy Electron Diffraction to demonstrate flatness and continuity of the films down to a thickness of approximately 2 atomic layers for the iron and 5 atomic layers for the silver. In the case of the thinnest iron layers, no large reduction of the ferromagnetic Curie temperature was observed, although this had been suggested and reported by other investigators. Furthermore, there was no indication for this particular growth system that the magnetization of the iron was out of the plane of the film. Variations of the magnetic hyperfine fields observed in the iron films were seen both as a function of iron thickness and as a function of the thickness of the intervening silver layers. For the thinnest films, the temperature dependence of the magnetization showed a linear behavior rather than the traditional T3/2 form.
Structural and Magnetic Properties of Epitaxial Co-Au Superlattices
Authors: Lee C. H. , He Hui , Lamelas F. , Vavra W. , Uher C. , Clarke Roy
Published: September 2012

We describe measurements on the structural and magnetic properties of Co–Au superlattices grown on Ge–buffered (110) GaAs by molecular beam epitaxy. Samples have been prepared with Co layer thicknesses ranging from 5–40Å and Au spacer layers of constant thickness, ∼ 16Å. X–ray scattering and high-resolution transmission electron microscopy show that the hcp Co layers grow epitaxially with the (0001) axis parallel to (111)Au and with the in–plane Co[1120] axis parallel to GaAs[001]. SQUID magnetometer measurements reveal a crossover in the magnetic anisotropy of the as–grown samples such that the easy axis is perpendicular to the substrate plane when the Co layer thickness is less than ∼19Å.
Novel Magnetic and Opto-Electronic Phenomena in Diluted Magnetic Semiconductor Multilayers
Authors: Furdyna J. K. , Samarth N.
Published: September 2012

We begin by reviewing earlier work involving the epitaxial growth of diluted magnetic semiconductor (DMS) layers, heterostructures and superlattices. We also describe current efforts at introducing new materials – such as Cd1-xMnxSe – to the family of MBE-grown DMS alloys. We then discuss some of the unique properties of DMS materials that make the study of thin film structures attractive, with particular emphasis on two general aspects. First, we look at the new opportunities in magnetism that are provided by epitaxially grown DMS films. Second, we examine some of the novel phenomena made possible by sp-d exchange effects in the context of DMS quantum well structures.
Critical behavior of Epitaxial Antiferromagnetic Insulator Films: Interdigital Capacitance Measurement of Magnetic Specific Heat
Authors: Lui M. , King A. R. , Jaccarino V. , Snider G. L.
Published: September 2012

An interdigital capacitance technique (ICT) for the measurement of magnetic specific heat (Cm) critical behavior of micron-thick epitaxial films of antiferromagnetic insulators (AF) has been developed. It was first applied to a study of high quality 3μm epitaxial films of FeF2 on lattice matching (001) oriented ZnF2 substrates. Under ideal preparatory conditions, the (Cm) results exhibit the divergent critical behavior of a 3-D Ising system. The ICT appears to be a useful method for characterizing the quality of AF films in regard to rms variations in the exchange interactions.
Laser Ablation Deposition (LAD) of Metallic Thin Films
Authors: Rebouiliat J. P. , Michelutti B. , Souche Y. , Gavigan J. P. , Givord D. , Lienard A.
Published: September 2012

Several experiments have been carried out to characterize the laser ablation deposition of metallic thin films as a function of the various process parameters. Ablation thresholds have been investigated for Al, Cu and Au targets as a function of wavelength as well as the fluence dependence of ablation rate. The effect of electric fields on the particle component of the ablated material has been investigated. Measurements of the velocity distribution of these particles have also been carried out for Al, Cu and Au targets as a function of the laser parameters with a view to using a velocity filter to remove the particles from the ablated beam.
HCP-FCC Transition in Epitaxial Co-Cu Superlattices
Authors: Lamelas F. J. , Lee C. H. , He Hui , Vavra W. , Clarke Roy
Published: September 2012

A series of epitaxial Co-Cu superlattices has been grown on GaAs (110) substrates by molecular beam epitaxy. Detailed analysis of x-ray diffuse scattering scans along Co (101ℓ) reveals a crossover from from the bulk hcp phase of Co to metastable fcc stacking. Our measurements indicate a strong correlation between structural symmetry and the magnetic anisotropy in Co - noble metal superlattices. In particular, the perpendicular easy axis of magnetization onsets at Co layer thickness ♣ 19 Å in Cohcp-Au compared to only ˜11 Å in Cofcc-Cu.
Temperature Dependence of Two-Dimensional Spin Anisotropies
Authors: Richter Roy , Gay Jack G.
Published: September 2012

Large anisotropy energy is an essential property of high quality permanent magnets. In previous work we have calculated the spin polarized electronic structure and anisotropy of monolayers and slabs of Fe, Ni, and V. In this work we calculate the dependence on temperature of the spin anisotropy of a ferromagnetic monolayer of Fe. We find the easy direction of magnetization is not sensitive to the temperature; the variations calculated here are likely too small to be observed. It is perpendicular to the plane of the surface for both low and high temperatures. The calculations become progressively more ill-behaved as the temperatures are lowered and require more computer time for satisfactory convergence.

For Fe/Cu {100}, we find the spins always prefer to point out of plane. Experimental results in general are consistent with this view, although the systems seem to be difficult to prepare.
The D-Band Exchange Splitting for Thin Gadolinium Overlayers
Authors: Lagraffe O. , Dowben P. A. , Onellion M.
Published: September 2012

Thin (0–6 monolayer) films of gadolinium on Cu(100) have been investigated using synchrotron radiation photoemission. From the definite selection of final state symmetries in photoemission, we have been able to determine a lower bound to the exchange splitting of the gadolinium 5d band. The gadolinium films on Cu(100) exhibit an exchange splitting that changes from approximately 1.1 eV to 0.6 eV as the overlayer thickness increases. The results for thicker films agree with the accepted values for the 5d exchange splitting of bulk gadolinium.
Growth, Characterization and Magnetic Properties Of HCP Fe/Ru Superlattices Synthetized by MBE
Authors: Maurer M. , Ousset J. C. , Piecuch M. , Ravet M. F , Sanchez J. P.
Published: September 2012

Hexagonal-close-packed Fex/Rux superlattices with the modulation along the (0001) axis, contaln fully hcp Fe layers. The interatomic Fe-Fe distances are enlarged by about 10% as compared to fcc Fe. Ferromagnetic behavior is found when Fe layers are thicker than about 4 monolayers.
Study of Medium-Deep Traps in Undoped GaAs Grown by Arsenic-Pressure Controlled Cz Method
Authors: Shiraki Hiroyuki , Tokuda Yutaka , Sassa Koichi
Published: September 2012

Properties of medium-deep traps in n-type undoped GaAs crystals grown by arsenic-pressure controlled Czochralski (PCZ) method were studied by using capacitance transient spectroscopy (CTS) and temperature-dependent Hall (TDH) measurement. EL3 and EL6-like (EM2) traps were dominant medium-deep traps in D LTS measurements. The dependence of EM2 peak height on the duration of filling pulse and the detailed analysis of CTS showed that the trap EM2 spectrum consisted of three electron traps which had thermal emission activation energies of approximately 0.35 eV and various capture cross sections with activation energies for electron capture. On the other hand, the trap EL6 spectrum in n-type LEC GaAs was described by two levels of traps with activation energies of 0.32 eV and 0.33 eV for electron emission, respectively. It was concluded that so-called EL6 formed a family and some of its components were classified as defects with large lattice relaxation.