bluuebunny/crossref_metadata_2025 huggingface dataset:
Strain-driven broken twin boundary coherence in YBa2Cu3O7−δ nanocomposite thin films
Authors: Guzman R. , Gazquez J. , Rouco V. , Palau A. , Magen C. , Varela M. , Arbiol J. , Obradors X. , Puig T.
Published: March 2013

In this letter we use high resolution scanning transmission electron microscopy to study epitaxial YBa2Cu3O7−δ (YBCO) nanocomposite thin films. We find that twin boundaries (TB) in YBCO nanocomposite thin films are disturbed by the presence of secondary phase nanoparticles as well as by intergrowths. Secondary phases promote the nucleation of TBs and, at the same time, result in bending, decreasing and changing the TB's spacing. On the other hand, the local strain ensuing from the partial dislocation associated to Y248 and Y125 intergrowths break the vertical coherence of TBs. This interaction results in a complex domain structure where twin boundary coherence is no longer satisfied and twin spacing is reduced down to a few nanometers precluding vortex channeling at low temperatures.
Enhanced amplified spontaneous emission from colloidal quantum dots in all-dielectric monolithic microcavities
Authors: Goldberg David , Menon Vinod M.
Published: March 2013

We report enhanced amplified spontaneous emission from CdSe/ZnS (core/shell) quantum dots embedded in an all-dielectric microcavity. The vertical cavity surface emitting structure was grown via plasma enhanced chemical vapor deposition and the quantum dots were sandwiched in the cavity layer via dip coating. The enhancement in emission is observed when the cavity mode is in resonance with the biexciton energy. The microcavity shows a factor of two improvement in the slope efficiency of amplified spontaneous emission along with significant modification in the directionality of the emission.
Multifractal analysis of validated wind speed time series
Authors: García-Marín A. P. , Estévez J. , Jiménez-Hornero F. J. , Ayuso-Muñoz J. L.
Published: March 2013

Multifractal properties of 30 min wind data series recorded at six locations in Cadiz (Southern Spain) have been studied in this work with the aim of obtaining detailed information for a range of time scales. Wind speed records have been validated, applying various quality control tests as a pre-requisite before their use, improving the reliability of the results due to the identification of incorrect values which have been discarded in the analysis. The scaling of the wind speed moments has been analysed and empirical moments scaling exponent functions K(q) have been obtained. Although the same critical moment (qcrit) has been obtained for all the places, some differences appear in other multifractal parameters like γmax and the value of K(0). These differences have been related to the presence of extreme events and zero data values in the data series analysed, respectively.
Energetic and exergetic analysis of three different solar cookers
Authors: Panwar N. L. , Kothari Surendra , Kaushik S. C.
Published: March 2013

This article deals with the energetic and exergetic analyses, which provides an alternative means of evaluating and comparing the performance of solar cookers. In this experimental setup, three different types of solar cookers have been studied during the typical day from November to January under Indian climatic conditions. The experimental time period was from 09:00 to 14:00 solar time. It was found that the animal feed cooker (AFC), hot box cooker (HBC), and parabolic dish type cooker (PDC) showed maximum energy and exergy efficiencies during the month of November compared to December and January. The energy efficiency of these cookers in November was about 36.74%, 60.94% and 14.45%, respectively, whereas exergy efficiency was 3.62%, 8.71%, 1.41%, respectively. The average energy output of AFC, HBC, and PDC during November was 247.80, 327.60, and 260.40 kJ/day, respectively, whereas the exergy output was 19.02, 33.32, and 21.34 kJ/day, respectively.
Threshold voltage dependence on channel length in amorphous-indium-gallium-zinc-oxide thin-film transistors
Authors: Han Kang Dong , Ung Han Ji , Mativenga Mallory , Hwa Ha Su , Jang Jin
Published: March 2013

A threshold voltage (Vth) dependence on channel length (L) is reported for amorphous-indium-gallium-zinc-oxide thin-film transistors (TFTs). Vth is found to shift negatively with decreasing L and the negative shift is drastic in TFTs with L < 4 μm. Combined analysis of current-voltage (I-V) and capacitance-voltage (C-V) curves shows that the Fermi energy (EF) at flat band shifts towards the conduction band (EC) with decreasing L, hence the negative Vth shift. Using the same analysis, the flat band carrier density (nFB) is also found to increase with decreasing L, revealing unintentional doping of the channel by carrier diffusion from the n+ doped source and drain regions as the cause of the negative Vth shift.
Quantitative determination of sheet resistance of semiconducting films by microwave near-field probing
Authors: Reznik Alexander N. , Demidov Evgenii V.
Published: March 2013

We propose and experimentally approve a method for determining the sheet resistance Rsh of a semiconducting film on a dielectric substrate from the near-field (NF) microwave measurements data. The method is based on the earlier developed theory for NF microscopy of plane layered media. The fitting parameters of the theoretical model were sought using a universal set of calibration standards, specifically, bulk-homogeneous Si slabs varying in the doping degree. Experimental investigations were assisted by a 3 GHz resonance probe with an aperture of about 1 mm. As test structures we used n-GaN films of 0.03–15 kΩ sheet resistance, grown on a sapphire substrate. The accuracy of the technique was assessed by comparing the NF probing data with the dc measurements of Rsh in the Van-der-Pauw (VDP) method. For Rsh < 4 kΩ the root-mean-square deviation of NF from VDP data is approximately equal to 20%.
Thickness-dependent evolutions of domain configuration and size in ferroelectric and ferroelectric-ferroelastic films
Authors: Huang C. W. , Chen Z. H. , Chen Lang
Published: March 2013

Non-monotonous thickness-dependent ferroelectric and ferroelectric-ferroelastic domain size scaling behaviors were revealed in ferroelectric films, including three distinct regions: (I) a classical ½ power law relationship for thick films, (II) a deviation from the ½ scaling relationship for an intermediate thickness range, and (III) an exponential increase in ultrathin films when decreasing the film thickness. The calculations indicate a much narrower region (II) in ferroelectric films with ferroelectric domains than that with ferroelectric-ferroelastic ones. As the film thickness decreases, the stable domain pattern also changes from a ferroelectric-ferroelastic domain to a ferroelectric one, which leads to the divergence of domain size scaling.
Rapid melt crystallization of amorphous-silicon thin films
Authors: Liu Fude , Wang Lei , Yang Guandong , Wang Wentao
Published: March 2013

We investigated the potential to melt crystallize amorphous Si thin films on glass with electromagnetic irradiation at 13.56 MHz, 2.45 GHz, and 110 GHz, respectively. We showed that the melt crystallization of millimeter-wave annealing could be an ideal choice for achieving high-quality semiconductor thin films with thickness in the micron range. In particular, silicon pillars with large ultra-high crystalline quality grains were experimentally realized by millimeter-wave annealing amorphous silicon on glass. Our simulation results were consistent with the experimental ones. Such understandings may enable us to prepare high-quality thin films on inexpensive substrates for solar cells and other solid-state devices.
Investigation of the critical behavior in Mn0.94Nb0.06CoGe alloy by using the field dependence of magnetic entropy change
Authors: Debnath J. C. , Shamba P. , Strydom A. M. , Wang J. L. , Dou S. X.
Published: March 2013

The critical behaviour of Mn0.94Nb0.06CoGe alloy around the paramagnetic-ferromagnetic phase transition was studied based on the field dependence on magnetic entropy change. By using the obtained exponents, the modified Arrott plot is consistent with that by using conventional method. These critical exponents are confirmed by the Widom scaling relation. Based on these critical exponents, the magnetization, field and temperature data around Tc collapse into two curves obeying the single scaling equation  M(H,  ε) = εβf ± (H/εβ+γ). The calculated critical exponents not only obey the scaling theory but also anastomose the deduced results from the Kouvel-Fisher method [J. S. Kouvel and M. E. Fisher, Phys. Rev. 136, A1626 (1964)]. The values deduced for the critical exponents in the Mn0.94Nb0.06CoGe alloy are close to the theoretical prediction of the mean-field model, indicating that the magnetic interactions are long range. This method eliminates the drawback due to utilization of multistep nonlinear fitting in a conventional manner. So it provides an alternative method to investigate the critical behaviour.
Imaging of fluorescence enhancement in photosynthetic complexes coupled to silver nanowires
Authors: Olejnik Maria , Krajnik Bartosz , Kowalska Dorota , Twardowska Magdalena , Czechowski Nikodem , Hofmann Eckhard , Mackowski Sebastian
Published: March 2013

Optical microscopy and spectroscopy of hybrid nanostructures composed of chlorophyll-containing photosynthetic complexes and silver nanowires reveal strong enhancement of fluorescence intensity of chlorophylls bound to the protein. This effect results from interaction between excited states of molecules embedded in the photosynthetic complex and plasmon excitations in metallic nanowires. Wide-field microscopy images reveal twofold increase of the emission intensity for complexes located at the ends of the nanowires as compared to the ones lying along the nanowires. Complementary spectrally and temporally resolved experiments indicate about 10-fold average increase of the chlorophyll fluorescence rate upon coupling with the metallic nanoparticles.
Polarization-insensitive and polarization-controlled dual-band absorption in metamaterials
Authors: Tuong P. V. , Park J. W. , Rhee J. Y. , Kim K. W. , Jang W. H. , Cheong H. , Lee Y. P.
Published: March 2013

We numerically and experimentally investigated dual-band absorption of sandwich-structure metamaterials which include periodic metal coupled rings at the front separated from the metal plane at the back by a dielectric layer. The properties are demonstrated in both GHz and mid-IR regimes of electromagnetic (EM) wave. The dual-band perfect absorber with polarization independence is observed under normal incidence. In order to understand the EM properties of dual-band perfect absorber, the plasmonic excitation was clarified for both peaks. Finally, by connecting the rings, the perfect-absorption peaks can be controlled with the polarization angle of incident EM wave.
Numerical stability analysis and rapid algorithm for calculations of fully developed laminar flow through ducts using time-marching method
Authors: Fukuchi Tsugio
Published: March 2013

In the numerical calculations of parabolic partial differential equations using explicit-type finite-difference methods (FDMs), the most fundamental finite-difference scheme is the time-forward, centered-space scheme. Under this scheme, several theoretical stability analysis methods have been established to avoid oscillations and divergences in numerical solutions. In solving elliptic partial differential equations using FDMs, the point successive over-relaxation method is one means to rapidly obtain steady state solutions, a major concern being to derive the optimum relaxation parameter. These problems have been solved theoretically over regular calculation domains. To be able to use FDMs freely over irregular calculation domains, the preceding two problems need to be reinvestigated but within a new theoretical framework. A theoretical approach is of great importance; nevertheless, it becomes so cumbersome that a numerical experimentation is the more realistic approach. A numerical approach—numerical stability analysis—is proposed and both problems are solved using similar algorithms. Although only the parabolic partial and elliptic differential equations concerned with Poiseuille flows are investigated here, the conclusions have a wider generality.
Intrinsic rapid Na+ intercalation observed in NaxCoO2 thin film
Authors: Shibata T. , Kobayashi W. , Moritomo Y.
Published: March 2013

Electrochemical properties are investigated for thin film electrode of NaxCoO2, which was fabricated by pulsed laser deposition. A high rate of 400 C was realized in the film together with a fine cyclability where its capacity after 1000 cycles remains 84.4% of the initial one. The NaxCoO2 thin film exhibits a clear sign of the structural phase transition induced by Na+ intercalation even at the high rate of 200 C. This observation indicates bulk nature of the rapid and highly-reversible Na+ intercalation in NaxCoO2.
Laser-induced precession of magnetization in ferrimagnetic GdFe thin films with low power excitation
Authors: Nishibayashi K. , Kuga K. , Munekata H.
Published: March 2013

We have investigated thermal effects on the dynamics of laser-induced precession of magnetization in ferrimagnetic GdFe thin films under low-excitation conditions (6-60 μJ/cm2). An increase in quasi-equilibrium temperature by laser heating causes a shift in precession frequency, which is explained analytically by the alteration of the magnetic anisotropy field by 2.2 [Oe] at a pulse fluence of 1 μJ/cm2. We have also demonstrated coherent control of the precession amplitude using a sequence of two laser pulses, each with a fluence of 18 μJ/cm2, and point out the importance of low-power excitation for precise control of the dynamic states.
Quasiresonant amplification of planetary waves and recent Northern Hemisphere weather extremes
Authors: Petoukhov Vladimir , Rahmstorf Stefan , Petri Stefan , Schellnhuber Hans Joachim
Published: March 2013

In recent years, the Northern Hemisphere has suffered several devastating regional summer weather extremes, such as the European heat wave in 2003, the Russian heat wave and the Indus river flood in Pakistan in 2010, and the heat wave in the United States in 2011. Here, we propose a common mechanism for the generation of persistent longitudinal planetary-scale high-amplitude patterns of the atmospheric circulation in the Northern Hemisphere midlatitudes. Those patterns—with zonal wave numbers m = 6, 7, or 8—are characteristic of the above extremes. We show that these patterns might result from trapping within midlatitude waveguides of free synoptic waves with zonal wave numbers k ≈ m. Usually, the quasistationary dynamical response with the above wave numbers
m
to climatological mean thermal and orographic forcing is weak. Such midlatitude waveguides, however, may favor a strong magnification of that response through quasiresonance.
From devastation to mobilisation: the Muslim community's involvement in social welfare in post-conflict DRC
Authors: Leinweber Ashley
                      E.
Published: March 2013

Undisputedly, more than a decade of war in the Democratic Republic of Congo has had an immensely negative impact on the social fabric of communities. However, tales of woe and destruction are not all that have arisen out of the ashes of the Congo wars. In fact, the minority Muslim community has capitalised upon the opportunity of this historical moment of state weakness and desperate human need to mobilise for the benefit of the larger society. Despite decades of marginalisation and withdrawal from political and development realms, in post-conflict DRC, Muslim associations are organising to provide social services, especially education.

[De la dévastation à la mobilisation : le rôle de la communauté musulmane dans la fourniture deles services sociaux dans la période après-conflit en RDC] Incontestablement, plus d'une décennie de guerre dans la République Démocratique du Congo a eu un impact très négatif sur la structure sociale des communautés. Pourtant, les histoires de malheur et de destruction ne sont pas les seules choses qui sont nées des cendres des guerres du Congo. En fait, la communauté minoritaire musulmane a misé sur l'opportunité de ce moment historique de faiblesse de l'État et de besoins humanitaires urgents pour se mobiliser en faveur de la société dans son ensemble. Malgré les décennies de marginalisation et le retrait des domaines politiques et du développement, dans la RDC d'après conflit, les associations musulmanes s'organisent pour fournir des services sociaux, en particulier dans le domaine de l'éducation.

Mots-clés : Congo ; Islam ; sciences politiques ; éducation ; états défaillants ; institutions hybrides
Making use of the past: the Rwandophone question and the ‘Balkanisation of the Congo’
Authors: Huening Lars-Christopher
Published: March 2013

Since the end of the second Congo war (1998–2003), the eastern Congolese provinces of North and South Kivu have remained in a state of neither war nor peace. With the re-emergence of rebellion in mid 2012, tensions have again risen between self-styled ‘native’ or ‘autochthon’ groups, and populations of both Congolese Hutu and Tutsi, often called ‘Rwandophones’. Whereas the former groups fear a looming ‘Rwandophone rise’, which will supposedly usher in Congo's ‘Balkanisation’, Rwandophone Hutu and especially Tutsi are afraid of marginalisation and renewed persecution. This article historicises the powerful meaning and tenacity of current fears of the ‘other’ that stand behind prevalent identity-markers and concepts such as ‘Rwandophone’ and ‘Balkanisation’, and which continue to fuel the present Kivutien identity conflict. In this regard, the period from c.1990 to 1996 was especially formative in the emergence of conflicting identities and the concurrent radicalisation of Congo's political discourse. From the vantage point of Kinshasa's press, this article reconstructs how the use of selective memories, claims about and mythico-historical visions of the past were instrumental in shaping Rwandophone identity formation.

[L'utilisation du passé : la question Rwandophone et la ‘Balkanisation du Congo’]. Depuis la fin de la deuxième guerre du Congo (1998–2003), les provinces de l'est du Congo, Nord-Kivu et Sud-Kivu, sont restées dans un état ni de guerre, ni de paix. Avec la réémergence de la rébellion à partir de la moitié de l'année 2012, des tensions sont de nouveau apparues entre des soi-disant groupes 'd'autochtones' ou 'd'indigènes' et des populations congolaises tant Hutu que Tutsi, souvent appelés ‘Rwandophones'. Alors que les groupes dits ‘autochtones’ craignent une ‘une montée imminente des Rwandophones’, laquelle conduirait vraisemblablement à une 'Balkanisation' du Congo, les populations dites ‘Rwandophone’, Hutu et en particulier Tutsi, craignent une marginalisation et une nouvelle persécution. Cet article retrace la puissante signification et la ténacité des peurs actuelles 'de l'autre' qui s'appuient sur des marqueurs d'identité existants et des concepts tels que la ‘Rwandophonie’ et la ‘Balkanisation', lesquels continuent d'alimenter le présent conflit d'identité dans les Kivu. À ce propos, la période de 1990 à 1996 était particulièrement décisive dans l'émergence d'identités opposées et de radicalisation simultanée du discours politique du Congo. Du point de vue de la presse de Kinshasa, cet article reconstruit la manière dont l'utilisation des souvenirs sélectifs, les revendications et les visions mythico-historiques du passé ont contribué à la structuration de la formation identitaire des Rwandophones.

Mots-clés : Congo ; identité ; Rwandophones ; Rwanda ; Balkanisation ; Kivus
Effectiveness of Influenza Vaccine for Preventing Laboratory-Confirmed Influenza Hospitalizations in Adults, 2011–2012 Influenza Season
Authors: Talbot H. Keipp , Zhu Yuwei , Chen Qingxia , Williams John V. , Thompson Mark G. , Griffin Marie R.
Published: March 2013

During the 2011–2012 influenza season, we enrolled hospitalized adults with acute respiratory illness and tested each for influenza using reverse transcription polymerase chain reaction. Influenza vaccination was verified in 35% (6/17) of adults with influenza-associated hospitalizations compared to 64% (97/152) of test-negative controls; adjusted vaccine effectiveness was 71.4% (95% confidence interval, 17.1%–94.9%).
1H Nuclear Magnetic Resonance (NMR) and Differential Scanning Calorimetry (DSC) Studies of Water Mobility in Dough Systems Containing Barley Flour
Authors: Lu Zhanhui , Seetharaman Koushik
Published: March 2013

This study used 1H nuclear magnetic resonance (NMR) spin‐spin relaxation time (T2) and differential scanning calorimetric (DSC) measurements of unfreezable water content (UFW), to assess water behavior in freshly prepared (25°C), refrigerator‐stored (4°C, one day), or freezer‐stored (–35°C, one day) doughs containing 5, 10, or 30% whole grain, air‐classified β‐glucan‐diminished, and air‐classified β‐glucan‐enriched (BGB‐E) barley flours. Three populations of water were detected by NMR, depending on moisture content of dough, namely, tightly (T21, 2–5 msec), less tightly (T22, 20–50 msec), and weakly (T23, 100–200 msec) bound water. T22 peak was always detectable, and T22 peak time linearly correlated to moisture content of dough in a range of 0.7–2.0 g/g db (r = 0.99, P < 0.05). Freezer storage showed less effect on water mobility in dough compared with refrigerator storage, whereas cooking and cool storage of cooked dough significantly decreased the water mobility (P < 0.05). Adding barley flour steadily decreased the water mobility in dough, and the reduction was more significant with adding BGB‐E (P < 0.05). Immobile water content was calculated by extrapolating T22 peak time versus total moisture content in dough and significantly correlated to the UFW content measured by DSC (r = 0.72, P < 0.05).
Sevoflurane Preconditioning Attenuates the Fall in Adenosine Triphosphate Levels, but Does Not Alter the Changes in Sodium and Potassium Levels during Hypoxia in Rat Hippocampal Slices
Authors: Esenther Brandon R. , Ge Zhijun , Meng Fanli , Cottrell James E. , Kass Ira S.
Published: March 2013

Background:

Sevoflurane preconditioning improves recovery after hypoxia. Sevoflurane administered before and during hypoxia improved recovery and attenuated the changes in intracellular sodium, potassium, and adenosine triphosphate (ATP) levels during hypoxia. In this study, the authors examine the effects of sevoflurane applied only before hypoxia on sodium, potassium, and ATP.

Methods:

Hippocampal slices from adult male Sprague–Dawley rats were pretreated with 4% sevoflurane, washed, and then subjected to hypoxia (n ≥ 8 animals/group). The cornus ammonis 1 regions of the hippocampal slices were micro-dissected and sodium, potassium, and ATP concentrations measured.

Results:

Pretreatment with sevoflurane for 15 or 60 min did not attenuate the increase in intracellular sodium or the decrease in intracellular potassium during hypoxia. After 60 min of preconditioning and 5 min of hypoxia, sodium increased 57% (vs. nonpreconditioned hypoxia 54% increase) and potassium decreased 31% (vs. 26%). These changes were not statistically significant versus untreated hypoxia. The 60-min sevoflurane preconditioning group had statistically significant higher ATP levels at 5 min of hypoxia (3.8 nmol/mg dry wt.) when compared to untreated hypoxic tissue (2.1 nmol/mg). There was no significant difference in ATP levels between the sevoflurane preconditioned and the untreated tissue before hypoxia (8.9 vs. 8.5 nmoles/mg, respectively).

Conclusion:

Preconditioning with sevoflurane for 60 min before hypoxia does not alter changes in intracellular sodium and potassium during hypoxia but does attenuate the fall in intracellular ATP levels during hypoxia. Thus, there are differences between anesthetic preconditioning and when anesthetics are present before and during hypoxia.
Burden of Illness and Use of Health Care Services Before and After Celiac Disease Diagnosis in Children
Authors: Mattila Eeva , Kurppa Kalle , Ukkola Anniina , Collin Pekka , Huhtala Heini , Forma Leena , Lähdeaho Marja‐Leena , Kekkonen Leila , Mäki Markku , Kaukinen Katri
Published: March 2013

Objectives:

Prevalence of celiac disease in children is approximately 1%, but most patients remain unrecognized by reason of variable clinical presentation. Undetected patients may have an increased burden of illness and use of health care services because of nonspecific complaints. We investigated these issues prospectively in newly detected patients with celiac disease before and after diagnosis in a large nationwide cohort of children.

Methods:

A validated questionnaire was sent to consecutive families whose children had been diagnosed as having celiac disease within 1 year. The survey contained questions about the use of medical consultations, on‐demand drugs, vitamins and herbal products, children's absenteeism from day care or school and, parents' work absenteeism. A follow‐up questionnaire was sent after 1 year of receiving a gluten‐free diet.

Results:

A total of 132 families responded. A total of 44 children were diagnosed because of gastrointestinal and 88 because of extraintestinal symptoms or by risk‐group screening. On treatment, outpatient visits to primary health care decreased from a mean of 3.0 to 1.3 visits per year (P < 0.001), the number of hospitalizations from 0.2 to 0.1 (P = 0.008), and antibiotic prescriptions from 1.0 to 0.5/year (P < 0.001). Visits to secondary and tertiary health care increased from 0.6 to 1.4 (P < 0.001), mostly for celiac surveillance. Use of vitamins, micronutrients, and herbal products increased from 7.3 to 10.2 pills per month (P = 0.028).

Conclusions:

Implementation of a gluten‐free diet resulted in reduced use of health care services and antibiotic prescriptions in children. Our findings support active case‐finding and risk‐group screening for celiac disease.
Increasing Incidence of Paediatric Inflammatory Bowel Disease in Northern Stockholm County, 2002–2007
Authors: Malmborg Petter , Grahnquist Lena , Lindholm Johan , Montgomery Scott , Hildebrand Hans
Published: March 2013

Objectives:

A sharp increase in paediatric (younger than 16 years) inflammatory bowel disease (IBD) incidence was observed in northern Stockholm County, Sweden, in 1990–2001. The increasing incidence was primarily explained by a rising incidence of Crohn disease (CD). Here, we present an update on the trends in incidence of paediatric IBD, 2002–2007.

Method:

Medical records of all children diagnosed as having suspected IBD in northern Stockholm County, 2002–2007, were scrutinised using defined diagnostic criteria. Disease extension, localisation, and behaviour at diagnosis were classified within the framework of the Paris classification.

Result:

A total of 133 children were diagnosed as having IBD 2002–2007 corresponding to a sex‐ and age‐standardised incidence (per 105 person‐years) for paediatric IBD of 12.8 (95% CI 10.8–15.2). The standardised incidence was 9.2 (95% CI 7.5–11.2) for CD and 2.8 (95% CI 1.9–4.0) for ulcerative colitis (UC). A significant increasing incidence of UC (P < 0.05) was observed during the study period. No temporal trend was observed for the incidence of CD.

Conclusions:

The incidence rate of paediatric IBD in northern Stockholm was significantly higher in 2002–2007 than that observed in our earlier study covering 1990–2001. The former sharp increase in incidence of paediatric CD seems, however, to have levelled out, although at a higher rate than reported from most other regions in the world. Although CD was still predominant, the observed increase in incidence of UC during the study period is notable.
Prosthecate sphingomonads: proposal of

Sphingomonas

canadensis sp. nov.
Authors: Abraham Wolf-Rainer , Estrela Andréia Bergamo , Rohde Manfred , Smit John , Vancanneyt Marc
Published: March 2013

Two stalked, aerobic, catalase- and oxidase-positive rod-shaped isolates, VKM B-1508 ( = CB 258) and FWC47T, were analysed using a polyphasic approach. While the morphology and the 16S rRNA gene sequence of strain VKM B-1508 were 100 % identical to the ones of

Sphingomonas leidyi

DSM 4733T, the morphology of FWC47T was different, and the closest recognized species were

Sphingomonas oligophenolica

S213T ( = DSM 17107T) and

Sphingomonas leidyi

DSM 4733T with 97.2 % and 97.0 % 16S rRNA gene sequence similarity, respectively. DNA–DNA hybridization studies supported the differentiation of strain FWC47T from

S. oligophenolica

and

S. leidyi

. Strain FWC47T grew optimally at 28–30 °C, and pH 6.0–8.0. The major respiratory quinone was Q10 and the major polyamine was sym-homospermidine. The major fatty acids were C17 : 1ω6c and C18 : 
1ω7c and C15 : 0 2-OH was the major 2-hydroxy fatty acid. The major polar lipids were phosphatidylglycerol, diphosphatidylglycerol, phosphatidyldimethylethylamine and unidentified sphingoglycolipids. The G+C content of the genomic DNA of strain FWC47T was 67.1 mol%. Strain FWC47T differed from

S. leidyi

by its ability to assimilate l-alanine, maltose and sucrose, by the presence of β-galactosidase and α-chymotrypsin, and the lack of valine arylamidase and β-glucosidase activities. Contrary to

S. leidyi

, FWC47T did not reduce nitrate and could not use fructose, acetate and N-acetyl-glusosamine. In the genus

Sphingomonas

, the dimorphic life cycle involving a prosthecate sessile and a flagellated swarmer cell was hitherto only known from

Sphingomonas leidyi

. Therefore, strain FWC47T represents an additional distinct prosthecate species in this genus for which the name

Sphingomonas

canadensis is proposed. The type strain is FWC47T ( = LMG 27141T = CCUG 62982T).
Description of

Xenorhabdus

khoisanae sp. nov., the symbiont of the entomopathogenic nematode Steinernema khoisanae
Authors: Ferreira Tiarin , van Reenen Carol A. , Endo Akihito , Spröer Cathrin , Malan Antoinette P. , Dicks Leon M. T.
Published: March 2013

Bacterial strain SF87T, and additional strains SF80, SF362 and 106-C, isolated from the nematode Steinernema khoisanae, are non-bioluminescent Gram-reaction-negative bacteria that share many of the carbohydrate fermentation reactions recorded for the type strains of recognized

Xenorhabdus

species. Based on 16S rRNA gene sequence data, strain SF87T is shown to be closely related (98 % similarity) to

Xenorhabdus hominickii

DSM 17903T. Nucleotide sequences of strain SF87 obtained from the recA, dnaN, gltX, gyrB and infB genes showed 96–97 % similarity with

Xenorhabdus miraniensis

DSM 17902T
. However, strain SF87 shares only 52.7 % DNA–DNA relatedness with the type strain of

X. miraniensis

, confirming that it belongs to a different species. Strains SF87T, SF80, SF362 and 106-C are phenotypically similar to

X. miraniensis

and

X. beddingii

, except that they do not produce acid from aesculin. These strains are thus considered to represent a novel species of the genus

Xenorhabdus

, for which the name

Xenorhabdus

khoisanae sp. nov. is proposed. The type strain is SF87T ( = DSM 25463T = ATCC BAA-2406T).
Chryseobacterium

carnipullorum sp. nov., isolated from raw chicken
Authors: Charimba George , Jooste Piet , Albertyn Jacobus , Hugo Celia
Published: March 2013

Three Gram-staining-negative, rod-shaped, non-spore-forming, non-motile, oxidase-positive, yellow pigmented and aerobic bacterial isolates designated 8_R23573, 9_R23581T and 10_R23577 were isolated from raw chicken at a broiler processing plant in Bloemfontein, South Africa. A polyphasic taxonomic approach was used to determine their exact taxonomic identities. Phylogenetic analysis of the 16S rRNA gene sequences showed that the three strains belonged to the genus

Chryseobacterium

, exhibiting the highest similarities to

Chryseobacterium shigense

DSM 17126T (98.6–99.2 %) and

Chryseobacterium luteum

DSM 18605T (98.3–98.7 %). The most abundant quinone was menaquinone MK-6 and the predominant cellular fatty acids were iso-15 : 0, iso-17 : 1ω9c, iso-17 : 0 3-OH and summed feature 3 (iso-16 : 1ω7c and/or iso-15 : 0 2-OH), which supported the affiliation of the strains to the genus

Chryseobacterium

. The DNA G+C contents of the strains were 36.9, 36.7 and 36.6 mol% respectively. The DNA–DNA hybridization results gave relatedness values ranging from 78.8 to 87.2 % among the three strains and 23.4 to 56.1 % to the two nearest phylogenetic neighbours

C. shigense

DSM 17126T and

C. luteum

LMG 23785T. On the basis of the data from this polyphasic study, the three strains are concluded to represent a novel species of the genus

Chryseobacterium

for which the name

Chryseobacterium

carnipullorum sp. nov. is proposed. The type strain is 9_R23581T ( = LMG 26732T = DSM 25581T).
Halopenitus malekzadehii sp. nov., an extremely halophilic archaeon isolated from a salt lake
Authors: Amoozegar Mohammad Ali , Makhdoumi-Kakhki Ali , Mehrshad Maliheh , Fazeli Seyed Abolhassan Shahzadeh , Ventosa Antonio
Published: March 2013

Strain CC65T, a novel extremely halophilic archaeon, was isolated from a brine sample of a salt lake in Iran. The novel strain was light yellow-pigmented, non-motile, pleomorphic and required at least 1.7 M NaCl and 0.02 M MgCl2for growth. Optimal growth was achieved at 3.5 M NaCl and 0.4 M MgCl2. The optimum pH and temperature for growth were pH 7.5 and 40 °C, respectively, while it was able to grow over a pH and a temperature range of pH 6.5–9.0 and 30–50 °C, respectively. Analysis of 16S rRNA gene sequence revealed that strain CC65Tclustered with the sole member of the genusHalopenitus,Halopenitus persicusDC30Twith a sequence similarity of 98.0 %. The polar lipid profile of strain CC65Tconsisted of phosphatidylglycerol and phosphatidylglycerol phosphate methyl ester. An unidentified glycolipid and two minor phospholipids were also observed. The only quinone present was MK-8(II-H2). The DNA G+C content of strain CC65Twas 63.8 mol%. On the basis of the biochemical and physiological characteristics, as well as DNA–DNA hybridization (44 % withHalopenitus persicusIBRC 10041T), strain CC65Tis classified as a novel species of the genusHalopenitus, for which the nameHalopenitusmalekzadehiisp. nov. is proposed. The type strain is CC65T( = IBRC-M 10418T = KCTC 4045T).
Site-Specific Labeling of RNA
Authors: Nilsen Timothy W.
Published: March 2013

In this protocol, RNAs containing a specific internally labeled phosphate are generated. The entire transcript of interest is synthesized using in vitro transcription. It is then digested with RNase H in the presence of a complementary chimeric oligonucleotide of the sequence 5′-NNNddddNNNNNNN-3′, where N is a 2′-O-methyl (2′ OMe) ribonucleotide and d is a de­oxy­nu­cle­o­tide. RNase H specifically cleaves the RNA in the oligonucleotide–RNA hybrid at the phosphodiester bond opposite the 5′-most deoxynucleotide, creating 3′-hydroxyl and 5′-phosphate termini. After dephosphorylation of the 5′ end of the 3′ fragment with phosphatase, this terminus is labeled to high specific activity with [γ-32P]ATP. The fragments of the original RNA are then resealed with T4 DNA ligase in the presence of a splint (or bridge) oligonucleotide. These labeled RNAs can be used in subsequent procedures to probe RNA–protein or RNA–RNA interactions.
Preparation of Transgenic Zebrafish Embryos for Imaging the Developing Retina
Authors: Jusuf Patricia , Harris William A. , Poggi Lucia
Published: March 2013

The zebrafish retina is an ideal model system for addressing neural fate specification in vivo. As in all vertebrate species studied, the retina is composed of seven major cell types distributed in a laminated histogenetic arrangement. The major connections and final positioning of cell types are well known, allowing lineage tracing and identification of final cell outcome by location, morphology, and subsequent immunostaining. The retina is conveniently located on the outside of the fish, allowing the embryos to be mounted such that the eye is close to the coverslip. This enables the entire structure to be imaged in four dimensions (4D) within the given focusing depth constraints. When preparing cells for lineage tracing, it is very important to label isolated cells mosaically, so that they stand out in a mostly unlabeled background. This can be achieved by transplanting cells from transgenic or injected embryos into uninjected embryos, as is described in this protocol. Transgenic (wild-type or mutant) embryos expressing stable green or red fluorescent protein (GFP or RFP) are used as donors, and non-transgenics or transgenics expressing a different fluorescent label are used as hosts. Mosaic labeling can also be achieved by DNA injection.
Brain Tumor Imaging: Live Imaging of Glioma by Two-Photon Microscopy
Authors: Madden Kelley S. , Zettel Martha L. , Majewska Ania K. , Brown Edward B.
Published: March 2013

Glioblastoma is a highly invasive and aggressive brain tumor that is very difficult to treat. The rat glioma cell line CNS-1 is a widely used, well-characterized model of infiltrative glioma. We have used CNS-1 to study tumors that initiate within the brain parenchyma. The CNS-1 cells were stably transfected with the yellow fluorescent protein (YFP) variant Venus to enable standard one-photon and two-photon imaging. In this protocol, we describe how to prepare a cranial window and how to inject the tumor cells into the cerebral cortex at a depth suitable for two-photon imaging. Imaging can begin 24 h after implantation of the cells. Two-photon imaging uses a long excitation wavelength (920 nm); the emission spectrum is the same for the fluorophore as for standard one-photon imaging (emission maximum = 528 nm). Two-photon microscopy permits tissue imaging to depths of 500 μm with three-dimensional (3D) high resolution and minimal photodamage to surrounding tissues. Multiple imaging sessions can be conducted over weeks in the same animal, depending on how long the cranial window remains clear and how quickly the tumor grows. Using this technique, the kinetics of tumor growth and invasion into the surrounding brain parenchyma can be measured in the same animal. This model can be used for determining the molecular and cellular players in brain tumor growth and invasion and for testing potential drug therapies to prevent brain metastasis.
BAC Transgenic Mice and the GENSAT Database of Engineered Mouse Strains
Authors: Schmidt Eric F. , Kus Laura , Gong Shiaoching , Heintz Nathaniel
Published: March 2013

The brain is a complex tissue comprising hundreds of distinct cell types, each of which has unique circuitry and plays a discrete role in nervous system function. Large-scale studies mapping gene-expression patterns throughout the nervous system have revealed that many genes are exclusively expressed in specific cell populations. The GENSAT (Gene Expression Nervous System Atlas) Project created a library of engineered mice utilizing bacterial artificial chromosomes (BACs) to drive the expression of enhanced green fluorescent protein (eGFP) in genetically defined cell populations. BACs contain large segments of genomic DNA and retain most of the transcriptional regulatory elements directing the expression of a given gene, resulting in more faithful reproduction of endogenous expression patterns. BAC transgenic mice offer a robust solution to the challenging task of stably and reproducibly accessing specific cell types from a heterogeneous tissue such as the brain. A significant advantage of utilizing eGFP as a reporter is the fact that it can fill entire cells, including neuronal dendrites and axons as well as glial processes, making GENSAT reporter mice a powerful tool for neuroimaging studies. This article provides a primer on the generation of BAC transgenic mice and advantages for their use in labeling genetically defined cell types. It also provides an overview of searching the GENSAT database and ordering engineered mouse lines.
Weaving webs of innovation
Authors: Fox Gavin L. , Smith Jeffery S. , Cronin J. Joseph , Brusco Michael
Published: March 2013

Purpose

This research aims to utilize a social network analysis approach to examine the effect of organizational position within a network of strategic partnerships on innovation as measured by perceptions of industry analysts. Specifically, the purpose of the paper is to examine how network characteristics such as degree centrality (being centrally located in a network), between centrality (being positioned as an intermediary), and closeness centrality (having a short average distance to all other firms in the network) affect the innovation ranking of the focal firm.

Design/methodology/approach

Data for 563 firms are generated from three distinct data sources (SDC Platinum: Alliances and Joint Ventures, COMPUSTAT, and Fortune's America's Most Admired Companies) and analyzed via social network analysis and linear regression.

Findings

The network characteristics of degree centrality and between centrality positively relate to industry perceptions or innovativeness whereas closeness centrality had no significant effect. Additionally, there were no discernable differences in innovativeness when comparing manufacturing firms to service organizations.

Research limitations/implications

Insignificant findings related to closeness centrality and the good/service differential may be attributable to the data sources, in that, the information is limited to firms within the respective sources. This data limitation may limit the potential of examining the effect of all network characteristics. Additionally, some included companies participate in multiple industries (i.e., have multiple SIC codes), which may serve as the blurring of any differences between good and service firms.

Practical implications

The results highlight the importance of considering strategic partnerships that establish configurations of partnership webs when pursuing innovation activities. Specifically, the findings suggest that firms should seek numerous strategic partnerships (high degree centrality) and attempt to broker information or control the extent to which partners collaborate (high between centrality). These results provide insights for firms seeking to establish new supply‐chain relationships in order to enhance their level of innovation.

Originality/value

This research provides a unique empirical examination of the impact of network positional characteristics on the innovativeness of a focal firm.
An interview with Wickham Skinner, Emeritus Professor at Harvard Business School
Authors: Brown Steve
Published: March 2013

Purpose

The aim of this series of papers is to offer key insights from eminent professors or practitioners within the field of Operations Management. This is the second of a series of interviews with “Operations Masters” and future contributions will include a range of inputs from manufacturing and services, private and public sectors. This series aims to provide an important contribution to the understanding of the strategic importance of operations management in a range of settings.

Design/methodology/approach

An interview with Professor Wickham, Emeritus Professor at Harvard Business School, a leading international figure in the field of operations management, whose contribution to operations manufacturing/strategy has been cited as seminal. The interview was conducted by Professor Steve Brown, Editor‐in‐Chief of International Journal of Operations & Production Management.

Findings

Wickham Skinner explains how he developed his reasoning behind his Harvard Business Review articles and books. He also describes how courses were developed at Harvard Business School to reflect the changing nature of business. He examines some of the challenges facing academics and practitioners alike in highly competitive, global business environments.

Originality/value

Professor Wickham Skinner is a leading international figure in the field of manufacturing and operations strategy. In this interview he offers key insights into how he first developed the notion of operations as a corporate concern. The message is highly relevant to academics and practitioners today.
ISO 9001 certification pay‐off: myth versus reality
Authors: Sampaio Paulo , Saraiva Pedro , Monteiro Ana
Published: March 2013

Purpose

Despite all the studies carried out in order to analyze the impact of quality management systems' implementation and certification on companies' financial performance, conclusions reached so far have a contradictory nature. Some authors conclude that there is a positive relationship between ISO 9001 certification and companies' financial improvement, while others do not find evidence to support such a relationship. The purpose of this paper is to present the main results derived from a research project developed in order to analyze the economical impact of quality management system implementation and certification on companies' performance.

Design/methodology/approach

This paper describes the results obtained from studying the economic impact of quality management systems, based on the adoption of a case study methodology. The authors' goal was to reconstruct the companies' financial history with the aim of identifying the benefits and costs directly related to their quality management systems. The analyzed time period ranged from the year when the company decided to implement its quality management system up to the present.

Findings

Results show that it is not unanimous that certified companies would be less profitable if they had not implemented their quality management systems.

Originality/value

This paper tries to be an important contribution to the worldwide research related to the quality management systems' impact on companies' financial performance.
Optimization of process factors for controlling defects due to melt shop using Taguchi method
Authors: Kumar Sushil , Satsangi P.S. , Prajapati D.R.
Published: March 2013

Purpose

The purpose of this paper is to identify the influencing factors which cause casting defects and determination of optimum value of factors to minimize these defects in a melt shop industry, situated in north India. Percentage contribution of these factors is also estimated to develop an empirical expression between process performance and independent input variables.

Design/methodology/approach

Optimization technique for melt shop process parameters of a cast iron differential housing cover based on the Taguchi method is proposed. The focus of this paper is on the robustness of the sand casting process and the case study is based upon a leading automobile foundry industry, located in north India. Taguchi's experimental design and regression analysis techniques are used to optimize the control factors, resulting in improvement of the product quality and stability. The various confirmation tests are also carried out in the range of process parameters.

Findings

The outcome of this case study is to optimize the process parameters of the melt shop process, which leads to minimizing the casting defects. The process parameters considered are: mild steel, pig iron, cast iron, ferrosilicon, lime stone, ferromanganese, cock and ferrochrome. Best proportions of charge constituents that are contributing to casting defects in melt shop are identified in the first stage. These identified factors are analyzed using “Design of Experiments” approach in the second stage. ANOVA analysis is also performed for robust design of factor values and an appropriate empirical model is formulated.

Research limitations/implications

A lot of effort has been put into developing the appropriate empirical model for the automobile foundry industry but additional work may also be done for gating design of the casting industry.

Practical implications

The paper shows that the process parameters of any casting industry can be optimized and casting defects in the melt shop can be identified in the first stage.

Originality/value

The research findings could be applied to various manufacturing industries, especially the casting industries.