bluuebunny/crossref_metadata_2025 huggingface dataset:
Effect of compliance during periodontal maintenance therapy on levels of bacteria associated with periodontitis: A 6‐year prospective study
Authors: Costa Fernando Oliveira , Vieira Thaís Riberal , Cortelli Sheila Cavalca , Cota Luís Otávio Miranda , Costa José Eustáquio , Aguiar Maria Cássia Ferreira , Cortelli José Roberto
Published: May 2018

Background

It is well established that regular compliance during periodontal maintenance therapy (PMT) maintains the stability of periodontal clinical parameters obtained after active periodontal therapy (APT). However, compliance during PMT has not yet been related to subgingival bacterial levels. Thus, this study followed individuals in PMT over 6 years and longitudinally evaluated the effects of compliance on periodontitis‐associated bacterial levels and its relation to periodontal status.

Methods

From a 6‐year prospective cohort study with 212 individuals in PMT, 91 were determined to be eligible. From this total, 28 regular compliers (RC) were randomly selected and matched for age and sex with 28 irregular compliers (IC). Complete periodontal examination and microbiological samples were obtained 5 times: T1 (prior to APT), T2 (after APT), T3 (2 years), T4 (4 years), and T5 (6 years). Total bacteria counts and levels of Actinomyces naeslundii, Porphyromonas gingivalis, Tannerella forsythia, and Treponema denticola were evaluated through quantitative polymerase chain reaction.

Results

RC had less tooth loss and better clinical and microbiological conditions over time when compared with IC. IC had higher total bacterial counts and higher levels of T. denticola. Moreover, among IC, total bacterial counts were positively associated with plaque index and bleeding on probing, while levels of A. naeslundii, T. forsythia, and T. denticola were negatively associated with clinical attachment loss (4 to 5 mm) among RC.

Conclusions

Compliance positively influenced subgingival microbiota and contributed to stability of periodontal clinical status. Regular visits during PMT sustained microbiological benefits provided by APT over a 6‐year period.
1,25‐dihydroxyvitamin D deficiency accelerates alveolar bone loss independent of aging and extracellular calcium and phosphorus
Authors: Gong Aixiu , Chen Jie , Wu Jun , Li Jing , Wang Lin , Goltzman David , Miao Dengshun
Published: May 2018

Background

Vitamin D is critical for bone homeostasis and immunomodulation. We therefore assessed whether 1,25‐dihydroxyvitamin D (1,25(OH)2D) deficiency in mice with targeted deletion of the gene encoding 25‐hydroxyvitamin D‐1α‐hydroxylase (1α(OH)ase [1αOH)ase−/−mice]) results in alveolar bone loss and periodontal inflammation in vivo.

Methods

Ten‐week‐old and 12‐month‐old 1α(OH)ase−/−mice and wild‐type littermates were fed a normal diet or a rescue diet, and the phenotype of the periodontium was then analyzed using microcomputed tomography, histology, immunohistochemistry, and real‐time Reverse transcription‐polymerase chain reaction (RT‐PCR).

Results

Alveolar bone loss was increased and maxillary bone mineral density (BMD), osteoblast numbers, and the number of osterix‐positive cells were decreased significantly in 1α(OH)ase−/−mice compared with wild‐type mice. Although aging from 10 weeks to 12 months accentuated these changes, and a rescue diet reduced them, the alterations in the 1α(OH)ase−/−mice exceeded the effects of aging and diet change. Nuclear factor kappa light‐chain‐enhancer of activated B cells (NF‐кB) p65 and CD3 positive cells, and the gene expression levels of interleukin (IL)‐1β, tumor necrosis factor (TNF)‐α, matrix metalloproteinase (MMP)‐3 and ‐8 were all increased significantly in periodontal tissues of 1α(OH)ase−/−mice compared with wild‐type mice. Aging from 10 weeks to 12 months also accentuated these changes, and a rescue diet reduced them, however, the alterations in the 1α(OH)ase−/−mice exceeded the effects of aging and diet change.

Conclusion

1,25(OH)2D deficiency in the 1α(OH)ase−/−mice accelerated alveolar bone loss by inhibiting osteoblastic bone formation and enhancing periodontal tissue degeneration in a calcium‐ and phosphorus‐ as well as an age‐independent manner.
Annexin‐1 as a salivary biomarker for gingivitis during pregnancy
Authors: Hassan Manar N. , Belibasakis Georgios N. , Gumus Pinar , Öztürk Veli Özgen , Emingil Gulnur , Bostanci Nagihan
Published: May 2018

Background

It is well established that there is higher susceptibility to gingival inflammation during pregnancy. Annexin‐1 (ANXA1) is an anti‐inflammatory protein which has been identified in gingival tissue exudates by discovery proteomics. This cross‐sectional case‐control study investigated the levels and association of ANXA1 and pro‐inflammatory mediator interleukin (IL)‐1β in the saliva of pregnant and non‐pregnant women.

Methods

Whole unstimulated saliva from 69 non‐pregnant and 78 pregnant women was collected prior to measurement of probing depth, clinical attachment level, bleeding on probing, and plaque. Then, the women were split into 3 subgroups depending on their periodontal status (healthy, gingivitis, and periodontitis). The levels of ANXA1 and IL‐1β were measured with enzyme‐linked immunosorbent assay and reported as pg/mg after normalizing against the total protein levels.

Results

Significantly higher ANXA1 levels were exhibited in pregnant women with gingivitis compared with health (P < 0.05) and in pregnant women with gingivitis compared with the respective non‐pregnant group (P < 0.0001). There was a significantly higher level of IL‐1β in gingivitis than in health in pregnant women (P < 0.05) and significantly higher levels in periodontitis compared with health in non‐pregnant women (P < 0.05). Looking at the IL‐1 β:ANXA1 ratio, the non‐pregnant periodontitis group displayed a significantly higher ratio compared with the respective pregnant group (P < 0.05). In the non‐pregnant subpopulation, the ratio was significantly higher in periodontitis compared with health (P < 0.01).

Conclusion

Salivary ANXA1 levels are elevated in the presence of gingivitis only in pregnant, but not non‐pregnant women, rendering this molecule as a potential salivary biomarker for non‐invasive early screening for gingival inflammation during pregnancy.
Patagonian ash on sub‐Antarctic South Georgia: expanding the tephrostratigraphy of southern South America into the Atlantic sector of the Southern Ocean
Authors: Oppedal Lea Toska , van der Bilt Willem G. M. , Balascio Nicholas L. , Bakke Jostein
Published: May 2018

Fingerprinting non‐visible volcanic ash (cryptotephra) enables precise dating and time synchronization of palaeoclimate archives. Recent analytical advances allow us to strengthen and expand existing tephrostratigraphical frameworks and harness the full potential of this powerful geochronological tool. Here, we present geochemical (electron microprobe) and chronological (14C) evidence to show that ash found in a peat section on the sub‐Antarctic island of South Georgia correlates to the ∼2950 cal a BP Alpehué eruption of the Chilean Sollipulli volcano. This discovery marks the first tephra fingerprint on South Georgia and expands the recently refined tephrostratigraphy of Patagonia ∼3000 km into the Southern Ocean. As deposition of this tephra horizon coincides with a major shift in regional atmospheric conditions, future finds may yield information on the spatiotemporal pattern of Southern Ocean climate dynamics.
Silent sinus syndrome without opacification of ipsilateral maxillary sinus
Authors: Lee David S. , Murr Andrew H. , Kersten Robert C. , Pletcher Steven D.
Published: May 2018

Silent sinus syndrome (SSS) is a rare disease characterized by spontaneous enophthalmos and hypoglobus secondary to collapse of the orbital floor in patients with asymptomatic maxillary sinusitis. Radiographic findings include ipsilateral maxillary sinus opacification, lateralization of the uncinate and middle turbinate, and infundibular occlusion. We present a case series of three patients with clinical and radiographic evidence of SSS but without maxillary sinus opacification. Although uncommon, an aerated maxillary sinus in patients with unexplained enophthalmos, hypoglobus, and maxillary atelectasis should not exclude the diagnosis of SSS. Laryngoscope, 128:2004–2007, 2018
Coastal zones as important habitats of coccolithophores: A study of species diversity, succession, and life‐cycle phases
Authors: Godrijan Jelena , Young Jeremy R. , Marić Pfannkuchen Daniela , Precali Robert , Pfannkuchen Martin
Published: May 2018

Coccolithophores are unicellular calcifying eukaryotes with a complex life‐cycle; they are important primary producers, and major drivers of global biogeochemical cycles. The majority of research on coccolithophores has been focused on open ocean waters, while the knowledge of their roles in coastal ecosystems is limited. Early 20thcentury studies of the Adriatic coast produced major taxonomic papers describing half of the projected diversity of coccolithophores. Afterwards, there have been only scarce records of their diversity and ecology in the Adriatic, and coastal systems in general. We aimed to assess coccolithophore diversity and species succession, and closely examine their ecological preferences in the coastal area of the northern Adriatic. We recorded coccolithophores throughout the year at 100% frequency, documented 52 taxa, abundances as high as 2.4 × 105cells L−1, and noted the winter domination over the phytoplankton community. Out of 52 observed coccolithophore taxa, 31 were heterococcolithophorids and 21 holococcolithophorids. Moreover, seven pairs of heterococcolith and holococcolith phases were noted, and two strategies of temporal separation of life‐cycle phases were observed. We report ecological preferences of those life‐cycle pairs and give in situ evidence that holo‐ and heterococcolith phases are widening the specie's ecological niches. This expansion allows the species to exploit a wider range of ecological conditions and enables phenotypic plasticity, important in response to changes in the environment. With this study we emphasize that coastal areas are highly productive for coccolithophore studies. Our results indicate that a shift in research effort on coccolithophores in the coastal waters is needed.
A radiation condition arising from the limiting absorption principle for a closed full‐ or half‐waveguide problem
Authors: Kirsch Andreas , Lechleiter Armin
Published: May 2018

In this paper, we consider the propagation of waves in a closed full or half waveguide where the index of refraction is periodic along the axis of the waveguide. Motivated by the limiting absorption principle, proven in the Appendix by a functional analytic perturbation theorem, we formulate a radiation condition that assures uniqueness of a solution and allows the existence of propagating modes. Our approach is quite different to the known one as, eg, considered recently by Fliss and Joly and allows an extension to open wave guides. After application of the Floquet‐Bloch transform, we consider the Bloch variable α as a parameter in the resulting quasiperiodic boundary value problem and study the behaviour of the solution when α tends to an exceptional value by a singular perturbation result, which goes back to Colton and Kress.
Group decision making with simplified neutrosophic ordered weighted distance operator
Authors: Şahin Rıdvan , Küçük Gökçe Dilek
Published: May 2018

Simplified neutrosophic set is a convenient tool proposed for dealing with complex problems; it is effective in providing more data for decision‐making process. In this study, we develop a simplified neutrosophic ordered weighted distance operator which combines the neutrosophic distance measures and the ordered weighted average distance in the same formulation. It is a new handy aggregation operator that considers the situations where the input data are represented in simplified neutrosophic numbers, and it also contains diverse distance aggregation operators. Parameterized families of simplified neutrosophic ordered weighted distance operator are handled. Moreover, we establish a new neutrosophic group decision‐making method based on the simplified neutrosophic ordered weighted distance operator, which has 2 extended approaches for determining the weights of decision makers and decision attributes in decision‐making process, respectively. Finally, an illustrative example demonstrates the application of the proposed method. The effectiveness and advantages of the proposed method are shown by the comparative analysis with existing relative methods.
Study the effects of nanofiber on the polymer chain orientation using molecular dynamic in the circular duct flow
Authors: Kanvisi Mojtaba
Published: May 2018

In this article, the effects of nanofiber on the polymer chain orientation are studied using molecular dynamic techniques in the circular duct flow. The conformational tensor models, which have root in the molecular dynamic, applied to simulate the polymer chain orientation in suspension of nanofibers. The effects of nanofiber aspect ratio are also investigated on the polymer chain orientation. The results show that the polymer chains are less oriented along the flow direction for more nanofiber concentration and consequently, the extensibility of the polymer chains decrease. In fact, the nanofibers prevent to stretch of polymer chains along the flow direction. Moreover, the results indicate that as increasing the aspect ratio of nanofibers, the czz components decrease but crr, cθθ, and czr components increase. It reveals that the polymer chains are less oriented along the flow direction for higher aspect ratio of nanofibers, and consequently, the length of polymer chains is reduced. POLYM. ENG. SCI., 59:15–21, 2019. © 2018 Society of Plastics Engineers
Experience matters: The role of academic scientist mobility for industrial innovation
Authors: Kaiser Ulrich , Kongsted Hans C. , Laursen Keld , Ejsing Ann‐Kathrine
Published: May 2018

Research Summary: A learning‐by‐hiring approach is used to scrutinize scientists' mobility in relation to the recruiting firms' subsequent innovation output. Our starting point is that among firm hires, individuals with university research experience—hired from universities or firms—can be particularly valuable. However, conflicting institutional logics between academia and industry makes working with academic scientists challenging at times for firms. We suggest two solutions to this difficulty: hiring “ambidextrous” individuals with a mix of experience of university research and working for a technologically advanced firm, and a strong organizational research culture in the recruiting firm reflected by the presence of a scientist on the top management team. We track the mobility of R&D workers empirically using patent and linked employer‐employee data.

Managerial Summary: An important way to make organizations more innovative is hiring individual researchers with the right types of skills and experience. We show that individuals with university research experience beyond their final degree are particularly likely to help boost firm‐level innovation output after hiring compared to R&D workers with other types of skills and experience. However, to obtain good returns to innovation from hiring such individuals, firms need a university research–friendly organizational culture when hiring individuals with university research experience, from either firms or academia.
Dual‐Modality Surface‐Enhanced Resonance Raman Scattering and Multispectral Optoacoustic Tomography Nanoparticle Approach for Brain Tumor Delineation
Authors: Neuschmelting Volker , Harmsen Stefan , Beziere Nicolas , Lockau Hannah , Hsu Hsiao‐Ting , Huang Ruimin , Razansky Daniel , Ntziachristos Vasilis , Kircher Moritz F.
Published: May 2018

Difficulty in visualizing glioma margins intraoperatively remains a major issue in the achievement of gross total tumor resection and, thus, better clinical outcome of glioblastoma (GBM) patients. Here, the potential of a new combined optical + optoacoustic imaging method for intraoperative brain tumor delineation is investigated. A strategy using a newly developed gold nanostar synthesis method, Raman reporter chemistry, and silication method to produce dual‐modality contrast agents for combined surface‐enhanced resonance Raman scattering (SERRS) and multispectral optoacoustic tomography (MSOT) imaging is devised. Following intravenous injection of the SERRS‐MSOT‐nanostars in brain tumor bearing mice, sequential MSOT imaging is performed in vivo and followed by Raman imaging. MSOT is able to accurately depict GBMs three‐dimensionally with high specificity. The MSOT signal is found to correlate well with the SERRS images. Because SERRS enables uniquely sensitive high‐resolution surface detection, it could represent an ideal complementary imaging modality to MSOT, which enables real‐time, deep tissue imaging in 3D. This dual‐modality SERRS‐MSOT‐nanostar contrast agent reported here is shown to enable high precision depiction of the extent of infiltrating GBMs by Raman‐ and MSOT imaging in a clinically relevant murine GBM model and could pave new ways for improved image‐guided resection of brain tumors.
International cooperation in meteorology, part 2: the golden years and their legacy
Authors: Zillman John W.
Published: May 2018

International cooperation in meteorology was one of the great success stories of the second half of the twentieth century. This article recalls the implementation of the World Weather Watch and the Global Atmospheric Research Programme (GARP) in the 1960s and 1970s, the challenges of the post‐GARP decades of the 1980s and 1990s and the legacy and lessons they provide for international cooperation in the twenty‐first century.
Targeting RNA in mammalian systems with small molecules
Authors: Donlic Anita , Hargrove Amanda E.
Published: May 2018

The recognition of RNA functions beyond canonical protein synthesis has challenged the central dogma of molecular biology. Indeed, RNA is now known to directly regulate many important cellular processes, including transcription, splicing, translation, and epigenetic modifications. The misregulation of these processes in disease has led to an appreciation of RNA as a therapeutic target. This potential was first recognized in bacteria and viruses, but discoveries of new RNA classes following the sequencing of the human genome have invigorated exploration of its disease‐related functions in mammals. As stable structure formation is evolving as a hallmark of mammalian RNAs, the prospect of utilizing small molecules to specifically probe the function of RNA structural domains and their interactions is gaining increased recognition. To date, researchers have discovered bioactive small molecules that modulate phenotypes by binding to expanded repeats, microRNAs, G‐quadruplex structures, and RNA splice sites in neurological disorders, cancers, and other diseases. The lessons learned from achieving these successes both call for additional studies and encourage exploration of the plethora of mammalian RNAs whose precise mechanisms of action remain to be elucidated. Efforts toward understanding fundamental principles of small molecule–RNA recognition combined with advances in methodology development should pave the way toward targeting emerging RNA classes such as long noncoding RNAs. Together, these endeavors can unlock the full potential of small molecule‐based probing of RNA‐regulated processes and enable us to discover new biology and underexplored avenues for therapeutic intervention in human disease.

This article is categorized under:

RNA Methods > RNA Analyses In Vitro and In Silico

RNA Interactions with Proteins and Other Molecules > Small Molecule–RNA Interactions

RNA in Disease and Development > RNA in Disease
The Sufficient and Necessary Condition for the Identifiability and Estimability of the DINA Model
Authors: Gu Yuqi , Xu Gongjun
Published: May 2018

Cognitive diagnosis models (CDMs) are useful statistical tools in cognitive diagnosis assessment. However, as many other latent variable models, the CDMs often suffer from the non-identifiability issue. This work gives the sufficient and necessary condition for identifiability of the basic DINA model, which not only addresses the open problem in Xu and Zhang (Psychometrika 81:625–649, 2016) on the minimal requirement for identifiability, but also sheds light on the study of more general CDMs, which often cover DINA as a submodel. Moreover, we show the identifiability condition ensures the consistent estimation of the model parameters. From a practical perspective, the identifiability condition only depends on the Q-matrix structure and is easy to verify, which would provide a guideline for designing statistically valid and estimable cognitive diagnosis tests.
Nano interface potential influences in CdTe quantum dots and biolabeling
Authors: Kanagasubbulakshmi S. , Kadirvelu K.
Published: May 2018

Nano interface influences in physiochemical properties of quantum dots (QDs) are the challenging approach to tailor its surface functionalities. In this study, a set of polar and non-polar solvents were selected to analyze the influences in solvent-based dynamic radius and surface potential of QDs. From the nano interface chemistry of polar and non-polar solvents, an appropriate mechanism of precipitation and hydrophobic ligand exchange strategy were elucidated by correlating Henry’s equation. Further, the in vitro cytotoxic potential and antimicrobial activity of QDs were assessed to perform biolabeling. From the observations, an appropriate dosage of QDs was fixed to label the animal ((RAW 264.7 cell lines) and bacterial cells (Escherichia coli) for effective cell attachment. Biolabeling was achieved by tailoring nano interface chemistry of QDs without additional support of biomolecules. Bacterial cell wall-based interaction of QDs was evaluated using SEM and EDAX analysis. Thus, provided clear insights into the nano interface chemistry in the development of highly photostable QDs will be helpful in biomedical applications.
Secular trends in the age at onset of bipolar I disorder – Support for birth cohort effects from interational, multi-centre clinical observational studies
Authors: Scott J. , Etain B. , Azorin J.M. , Bellivier F.
Published: May 2018

Objective:

To examine any association of birth decade, sex and exposure to alcohol and/or substance use disorders (ASUD) with age at onset (AAO) of bipolar I disorder (BD-I).

Methods:

Using data from a representative clinical sample of 3896 BD-I cases recruited from 14 European countries, we examined AAO distributions in individuals born in consecutive birth decades. Cumulative probabilities with Mantel-Cox log-rank tests, pairwise comparisons and Odds Ratios (OR) with 95% confidence intervals (95% CI) were employed to analyze AAO according to birth decade, sex, and presence or absence of an ASUD.

Results:

In the total sample, median AAO of BD-I decreased from about 41 years for those born in the 1930s to about 26 years for those born in the 1960s. In a sub-sample of 1247 individuals (selected to minimize confounding), AAO significantly decreased for males and females born in each consecutive decade between 1930 and 50 (OR: 0.65; 95% CI: 0.51, 0.81), and for cases with an ASUD as compared to without (OR: 0.77, 95% CI: 0.69, 0.87). The best fitting regression model identified an independent effect for each birth decade and an interaction between ASUD status and sex, with a consistently earlier AAO in males with an ASUD (OR: 0.79: 95% CI: 0.70, 0.91).

Conclusions:

In BD-I cases diagnosed according to internationally recognized criteria and recruited to pan-European clinical observational studies, the AAO distributions are compatible with a birth cohort effect. A potentially modifiable risk factor, namely ASUD status, was associated with the observed reduction in AAO, especially in males.
Association Between Psoriasis and Erectile Dysfunction: A Meta-Analysis
Authors: Wu Tao , Duan Xi , Chen Shulin , Chen Xiaobin , Yu Ruichao , Yu Xiaodong
Published: May 2018

Background

Several studies have shown a relationship between psoriasis and erectile dysfunction (ED), but a meta-analysis of the data has not been performed.

Aim

To conduct a comprehensive meta-analysis of existing evidence to quantify and compare the risk of ED with psoriasis.

Methods

A systematic literature search was conducted using MEDLINE, EMBASE, Cochrane databases, and Google Scholar. We calculated pooled odds ratios (OR), standardized mean difference (SMD), and 95% CI.

Outcomes

Outcome measures included characteristics of included studies, association between psoriasis and ED risk, and association for adjusted-for-covariates studies between psoriasis and ED risk.

Results

In total, 9 studies with 36,242 psoriasis patients and 1,657,711 controls (participants without psoriasis) met inclusion criteria and showed that there was statistically significant association between psoriasis and ED risk (OR 1.35; 95% CI 1.29–1.41; P < .00001; I2 = 44%). A significant association for adjusted-for-covariates studies between psoriasis and ED risk was also observed (OR 1.22; 95% CI 1.08–1.37; P = .002; I2 = 43.8%). It revealed the International Index of Erectile Function-5 score was statistically significantly lower in the psoriasis group than controls (SMD −3.09; 95% CI −4.81 to −1.37; P = .0004; I2 = 77%). A subgroup analysis was performed to potentially explain heterogeneity. It examined the main potential sources of inter-study variance including variance sample sizes and different assessment tools for ED.

Clinical Translation

The risk of ED in psoriasis patients should also be assessed by physicians.

Conclusions

This study is a well-designed and comprehensive meta-analysis to examine the relationship between psoriasis and risk of ED. However, the included studies are mostly cross-sectional or have small sample cohorts, which could bring bias and heterogeneity into the analysis. Our findings support the hypothesis that psoriasis is associated with an increased risk of ED. Furthermore, additional prospective cohort studies are needed to elucidate these relationships and to advance knowledge in this field.
Local transport of passive scalar released from a point source in a turbulent boundary layer
Authors: Talluru K. M. , Philip J. , Chauhan K. A.
Published: May 2018

Simultaneous measurements of streamwise velocity ($\tilde{U}$) and concentration ($\tilde{C}$) for a horizontal plume released at eight different vertical locations within a turbulent boundary layer are discussed in this paper. These are supplemented by limited simultaneous three-component velocity and concentration measurements. Results of the integral time scale ($\unicode[STIX]{x1D70F}_{c}$) of concentration fluctuations across the width of the plume are presented here for the first time. It is found that$\unicode[STIX]{x1D70F}_{c}$has two distinct peaks: one closer to the plume centreline and the other at a vertical distance of plume half-width above the centreline. The time-averaged streamwise concentration flux is found to be positive and negative, respectively, below and above the plume centreline. This behaviour is a resultant of wall-normal velocity fluctuations ($w$) and Reynolds shear stress ($\overline{uw}$). Confirmation of these observations is found in the results of joint probability density functions of$u$(streamwise velocity fluctuations) and$\tilde{C}$as well as that of$w$and$\tilde{C}$. Results of cross-correlation coefficient show that high- and low-momentum regions have a distinctive role in the transport of passive scalar. Above the plume centreline, low-speed structures have a lead over the meandering plume, while high-momentum regions are seen to lag behind the plume below its centreline. Further examination of the phase relationship between time-varying$u$and$c$(concentration fluctuations) via cross-spectrum analysis is consistent with this observation. Based on these observations, a phenomenological model is presented for the relative arrangement of a passive scalar plume with respect to large-scale velocity structures in the flow.
Learning by Doing: The First Spanish Nuclear Plant
Authors: De la Torre Joseba , del Mar Rubio-Varas Maria
Published: May 2018

In the nuclear sector, turnkey projects can be considered an investment in obtaining information through “learning by doing” to capture rents from the next generation of reactors. As the first U.S. turnkey export project, the first Spanish nuclear power plant served that purpose and paved the way for the subsequent growth of the nuclear sector, for both Spanish and U.S. firms. Making use of archival material, we analyze the networks created by the government, experts, and business leaders, which sought to obtain, accumulate, and learn from the scarce and conflicting information about atomic technology that was available at the time. We also discern how firms on both sides of the Atlantic acquired and perfected the specific capabilities required to build a commercial nuclear reactor.
Going South: Tracing Race and Region in the Post-Emancipation Black Atlantic
Authors: ENGEL ELISABETH , GRANT NICHOLAS
Published: May 2018

The demise of American slavery in 1865 put black Americans in motion to an unprecedented degree. Freed slaves and their descendants migrated from the plantations in the rural South to destinations around the globe. Travelling in a variety of new roles – as missionaries, journalists, agronomists, scientists, athletes, performers, entrepreneurs and political activists – African Americans gained international visibility, inspiring other oppressed populations in the colonial world to struggle for their liberation.
Fuller's earth from near Dry Branch., Georgia, a montmorillonite-cristobalite clay
Authors: Brindley G. W.
Published: May 2018

Fuller's earth from near Dry Branch, Georgia, is shown by X-ray analysis to contain comparable amounts of montmorillonite and cristobalite, and only minor amounts of other minerals. The cristobalite resembles the high form, but may be a very disordered low form. Electron micrographs show the montmorillonite to be lath-like, and the cristobalite globular in form.
The clay mineralogy of some tills in the Cambridge district
Authors: Perrin R. M. S.
Published: May 2018

Four ice advances have been recognised in East Anglia but only two of these, the Lowestoft and the Gipping, have deposited till in the Cambridge area. The clay fractions of these tills have been investigated and compared with those of the Oxford, Ampthill, Kimeridge and Gault Clays, the Lower Greensand and the Chalk, all of which outcrop in the district and could be expected to contribute material to the tills.

The value of clay mineralogical analysis as a means of measuring directions of ice-movement is critically discussed.

An outline account is given of the more important processes of weathering and soil-formation which occur on the Gipping till in the Breckland area.
Giving your SEM or FIB a Helping Hand
Authors: Rowlands Neil , Frayne Gavin , Hansen Bo Svarrer
Published: May 2018

Scanning electron microscopes have traditionally been used for observation and microanalysis of samples. Positioning and testing of samples has usually been performed out of the SEM chamber e.g. electrical test benches, sample preparation. However, due to miniaturization in semiconductor technology, optics, micro-mechanics, medicine, gene- and biotechnology, highly precise positioning techniques are becoming increasingly important. This may be performed using an optical microscope, or more commonly, within the SEM chamber itself.
Spatial Resolution in ACOM - What Will Come After EBSD
Authors: Schwarzer RA
Published: May 2018

Automated Crystal Orientation Microscopy (ACOM) on a grain specific level has proved to be an invaluable new tool for characterizing polycrystalline materials. It is usually based on scanning facilities using electron diffraction , due to its high sensitivity and spatial resolution, but also attempts have been made which rely upon X-ray or hard synchrotron radiation diffraction. The grain orientations are commonly mapped in pseudo-colors on the scanning grid to construct Crystal Orientation Maps (COM), which represent “images” of the microstructure with the advantage of providing quantitative orientation contrast. In a similar way, misorientations across grain boundaries, Σ values of grain boundaries, or other microstructural characteristics are visualized by mapping the grains in the micrograph with specific colors. The principal objectives are the determination of quantitative, statistically meaningful data sets of crystal orientations, misorientations, the CSL character (Σ) of grain boundaries, local crystal texture (pole figures, ODF, MODF, OCF) and derived entities, phase discrimination and phase identification.
Microscopy used to Show how Spiders Hide!
Authors: Carmichael Stephen W
Published: May 2018

It has been appreciated that many invertebrates have morphologic and/or behavioral traits that help them survive by camouflage for predator avoidance or being stealthy predators themselves. The morphologic features that are involved have been described in greater detail as the technology has evolved. Recently, Rebecca Duncan, Kellar Autumn, and Greta Binford have used dissecting microscopes and scanning electron microscopes (SEM) to reveal new details of how certain species of spiders hide themselves by covering themselves with sand, and how the sand particles tenaciously stick to the spiders’ bodies.
Unique Minilens Cooling System Results in a Compact TEM
Authors: Lysenkov Dmitry , Monigle William C
Published: May 2018

Transmission electron microscopy (TEM) has been proven to be one of the most convenient and straight forward methods for resolving sub-nanometer structures. The use of these instruments in life sciences, materials sciences and in the semiconductor industry has contributed greatly to many significant advances. However, typical TEMs are very large, expensive and relatively complicated to operate. Fortunately, recent advances in TEM technology and product design have created a new TEM instrument that is very well suited to everyday applications in hospitals, universities and laboratories of all types. Able to fit in a small room, this new TEM does not require the expensive, extensive building modifications usually associated with a TEM installation.
Modified Cryo-Preparation for Studying Salt Glands in the Turf Grass Zoysia matrella
Authors: Rao Sheetal , Pendleton Michael W , Binzel Marla L , Ellis E Ann
Published: May 2018

Zoysia, a common turf grass, is characterized by the presence of functional salt glands. These glands are specialized structures through which the plants excrete excess salt. Research on the mechanism of salt secretion in Zoysia matrella (Manila grass) prompted the development of a specimen preparation technique that would preserve the secreted salt and salt gland. Conventional aqueous preparative techniques wash away the secreted salt on the leaf surface. A specimen preparation technique was modified from a simple cryo-preparative technique for examining hydrogels in the transmission electron microscope.
Using Iodine Vapour Staining to Visualize Starch Distribution in a Dry, Extruded Food
Authors: Bond Jacquie , Hardacre Allan K
Published: May 2018

Food ingredients are often made by extruding flours and starches derived from cereal grains with proteins. Extrusion is carried out at high temperature, high shear and low water conditions to make low density, foamed pellets that are used as food ingredients. The structure of the crisp matrix varies greatly with the ingredient proportion and is important in forming the organoleptic properties of the crisps. However, it is very difficult to analyse the structure of the matrix with respect to the distribution of the major components, and the authors have been unable to find references for these materials. Furthermore, the materials must be stained without wetting as water will destroy the integrity of the crisps.
A Method to Characterize and Correct Elliptical Distortion in Electron Diffraction Patterns
Authors: Hou Vincent D-H , Li Du
Published: May 2018

One of the main obstacles to performing electron crystallography analysis in a TEM is that the acquired electron diffraction data often exhibits some form of distortion introduced by the lens system. Recognizing this problem, Capitani et al. has proposed a method to detect such distortion, which is primarily elliptical, by using a single crystal standard. Once such elliptical distortion is characterized, electron diffraction data acquired later can then be corrected by means of image processing. However, it may be desirable to correct such distortion at the instrument level. In this article, a different approach to measuring diffraction elliptical distortion is proposed by characterizing diffraction ring patterns and it is demonstrated that by varying the objective lens stigmation settings, it is possible to eliminate this elliptical distortion completely.
Insect Epicuticular Grease Visualised by Scanning Probe Microscopy
Authors: Gorb Stanislav , Voigt Dagmar , Peisker Henrik
Published: May 2018

The covering wings (elytra) in the Colorado potato beetle Leptinotarsa decemlineata appear shiny, smooth, water-repellent, and slightly slippery, (Fig. 1). These properties are due to the presence of epicuticle, the outermost layer of the insect integument, covered by a wax-like lipid surface layer called grease. Surface waxes have been previously reported in a variety of conditions, from liquid viscous coatings to crystalline structures in form of plates, rods and filaments from many insects (adults and larvae) and arachnids (Hadley, 1981a,b). Beament (1945) and Wigglesworth (1945) considered an outer thin layer of solid wax, whereas Lewis (1962) rather assumed an oil film on the epicuticle surface to be widespread throughout insects.
How Much Force Does it Take to Move an Atom on a Surface?
Authors: Carmichael Stephen W
Published: May 2018

It was demonstrated 18 years ago that atoms could be manipulated, one at a time, on a surface. Yet only recently has the force required to move an atom been determined. Markus Ternes, Christopher Lutz, Cyrus Hirjibehedin, Franz Giessibl, and Andreas Heinrich, in a technical tour de force, have engineered a microscope that incorporates features of the scanning tunneling microscope (STM) and atomic force microscope (AFM) to accurately quantitate the lateral and vertical forces needed to move a single atom on a surface.
Testing Parameters for Two-Dimensional Crystallization and Electron Crystallography on Eukaryotic Membrane Proteins with Liposomes as Controls
Authors: Zhao Gengxiang , Mutucumarana Vasantha , Stafford Darrel W , Kanaoka Yoshihide , Austen K Frank , Schmidt-Krey Ingeborg
Published: May 2018

Membrane proteins comprise the majority of known and potential drug targets, yet have been immensely difficult to analyze at the structural level due to their location in the membrane bilayer. Removal from the membrane necessitates replacement of the phospholipid bilayer by detergents in order to maintain protein solubility. However, the absence of lipids and the presence of detergents can render non-physiological conformational changes of the membrane protein (Tate, 2006). Electron crystallography is an important method for studying membrane proteins that usually takes advantage of reconstituting the protein in a phospholipid bilayer and removal of the detergent. Richard Henderson and Nigel Unwin used this technique to elucidate the three-dimensional (3D) arrangement of the transmembrane α-helices of bacteriorhodopsin, which was the first 3D structural information on a membrane protein (Henderson and Unwin, 1975).
Hardware and Techniques for Cross- Correlative TEM and Atom Probe Analysis
Authors: Gorman Brian P , Diercks David , Salmon Norman , Stach Eric , Amador Gonzalo , Hartfield Cheryl
Published: May 2018

Atom probe tomography has primarily been used for atomic scale characterization of high electrical conductivity materials. A high electrical field applied to needle-shaped specimens evaporates surface atoms, and a time of flight measurement determines each atom's identity. A 2-dimensional detector determines each atom's original position on the specimen. When repeated successively over many surface monolayers, the original specimen can be reconstructed into a 3-dimensional representation. In order to have an accurate 3-D reconstruction of the original, the field required for atomic evaporation must be known a-priori. For many metallic materials, this evaporation field is well characterized, and 3-D reconstructions can be achieved with reasonable accuracy.
Imaging Skin Epidermal Stem Cells: A Review
Authors: Pasolli Hilda Amalia
Published: May 2018

Nature has provided us with a wonderful outer surface, the skin. We humans are fascinated with our epidermis and hair. We spend an exorbitant amount of time and money on skin and hair maintenance. We try hard to keep it soft, smooth, radiant, tan or pale, clean or made-up. We try to remove hair from some areas as hard as we try to keep it on others. Only when our skin is afflicted by disease, burns, wounds, or scratches is it apparent that this amazing outer shell protects us from dehydration and infections. To perform this crucial protective function and to be able to respond to injuries, skin needs to undergo self-renewal to repair damaged tissue and to replace old cells. For this formidable task, skin depends on stem cells. Stem cells have the ability to self-perpetuate and to give rise to differentiating cells that constitute one or more tissue types.
LED Light Source: Major Advance in Fluorescence Microscopy
Authors: Hohman Becky
Published: May 2018

Fluorescence microscopy requires an intense light source at the specific wavelength that will excite fluorescent dyes and proteins. The traditional method employs a white light, typically from a Mercury or Xenon arc lamp. Although such broad-spectrum lamps can generate ample light at desired wavelengths, only a small percentage of the projected light is useful in any particular application. The other wavelengths need to be suppressed to avoid background noise that reduces image contrast and obscures the fluorescent light emissions.

This process of suppressing extraneous light is complex, expensive, and only partially effective: even after decades of refinements, the best filters are not 100% percent successful at blocking the bleed through of non-specific photons. Some mitigation techniques end up not only suppressing peripheral light, but also significantly diminishing the intensity of the desired wavelengths. To address the root cause of the problem – the presence of non-specific photons – a radically different approach is coming to light.
CellProfiler: Open-Source Software to Automatically Quantify Images
Authors: Vokes Martha S , Carpenter Anne E
Published: May 2018

Researchers often examine samples by eye on the microscope — qualitatively scoring each sample for a particular feature of interest. This approach, while suitable for many experiments, sacrifices quantitative results and a permanent record of the experiment. By contrast, if digital images are collected of each sample, software can be used to quantify features of interest. For small experiments, quantitative analysis is often done manually using interactive programs like Adobe Photoshop©. For the large number of images that can be easily collected with automated microscopes, this approach is tedious and time-consuming. NIH Image/ImageJ (http://rsb.info.nih.gov/ij) allows users comfortable writing in a macro language to automate quantitative image analysis. We have developed Cell- Profiler, a free, open-source software package, designed to enable scientists without prior programming experience to quantify relevant features of samples in large numbers of images automatically, in a modular system suitable for processing hundreds of thousands of images.
Imaging Multilayers of Ice with Scanning Tunneling Microscopy
Authors: Thürmer Konrad , Bartelt Norman C
Published: May 2018

Ice plays an important role in many naturally occurring phenomena. For example, most rainfall in temperate climates is triggered by the nucleation of ice around μm-sized particles in atmospheric clouds. Another reason to be interested in ice is that thin supported ice films provide excellent model systems for studying the interaction of water with solid surfaces. Despite the importance of water-solid interactions for catalysis, corrosion, water purification and fuel cells, even the basics of this interaction are poorly understood. In fact, the best theoretical models often fail to predict even the simplest phenomena. A fundamental question, for example, is whether water/ice wets a given substrate, i.e., whether the substrate is covered up by a uniformly thick water/ice film. (In the case of non-wetting an ice film would break up into separate three-dimensional (3D) crystallites of varying height, exposing the substrate.)
Application of the Gatan X-ray Ultramicroscope (XuM) to the Investigation of Material and Biological Samples
Authors: Mainwaring Paul
Published: May 2018

X-ray ultramicroscopy in the SEM is a relatively new application in the wider field of X-ray microscopy. This latter field includes synchrotron and cabinet-based systems that vary in their X-ray power, capability, sample size, spatial resolution, and convenience. One important capability of the SEM-hosted X-ray microscope is that the normal SEM imaging and analytical functions such as secondary and backscattered imaging and microanalysis by EDX or WDS are unimpeded. X-ray imaging then serves as a complement to the normal use of the SEM. The convenience of easy access in an SEM lab to an X-ray microscope with 3D tomographic capability makes this an important development.
Mathematische Konzepte bei gehörlosen Vorschulkindern und Erstklässlern
Authors: Werner Viktor , Masius Malwine , Ricken Gabi , Hänel-Faulhaber Barbara
Published: May 2018

Zusammenfassung. In Untersuchungen zu mathematischen Fähigkeiten gehörloser und hörbehinderter Schülerinnen und Schülern zeigt sich in der internationalen Fachliteratur ein deutlicher Entwicklungsrückstand gegenüber hörenden Gleichaltrigen. Allerdings ist bisher kaum bekannt, welche Entwicklung gehörlose Kinder zum mathematischen Wissen im Vergleich zu hörenden Kindern durchlaufen. Für den MARKO-D – ein Test zur Erfassung der mathematischen Kompetenz von hörenden Kindern im Vorschulalter – wurde nach sorgfältigen gebärdensprachlinguistischen und mathematikdidaktischen Prüfungen eine Übersetzung in die Deutsche Gebärdensprache (DGS) erstellt. In einer Pilotstudie wurde diese Testadaption des MARKO-D mit einer Gruppe gehörloser Kinder durchgeführt. Es zeigte sich einerseits der bisher beschriebene Rückstand in der Entwicklung, andererseits bewältigen gehörlose Kinder Aufgaben zum ordinalen Zahlenstrahl und Aufgaben, die ein relationales Verständnis erfordern, anders als hörende Kinder. Die Lösungsmuster werden vor dem Hintergrund der Übersetzungsmöglichkeiten in die DGS diskutiert. Mögliche sprachspezifische Besonderheiten für die mathematische Entwicklung werden thematisiert.