bluuebunny/crossref_metadata_2025 huggingface dataset:
Computational Fluid Dynamics–Habitat Suitability Index (CFD–HSI) Modelling as an Exploratory Tool for Assessing Passability of Riverine Migratory Challenge Zones for Fish
Authors: Haro A. , Chelminski M. , Dudley R. W.
Published: June 2015

We developed two‐dimensional computational fluid hydraulics–habitat suitability index (CFD–HSI) models to identify and qualitatively assess potential zones of shallow water depth and high water velocity that may present passage challenges for five major anadromous fish species in a 2.63‐km reach of the main stem Penobscot River, Maine, as a result of a dam removal downstream of the reach. Suitability parameters were based on distribution of fish lengths and body depths and transformed to cruising, maximum sustained and sprint swimming speeds. Zones of potential depth and velocity challenges were calculated based on the hydraulic models; ability of fish to pass a challenge zone was based on the percent of river channel that the contiguous zone spanned and its maximum along‐current length. Three river flows (low: 99.1 m3 sec‐1; normal: 344.9 m3 sec‐1; and high:792.9 m3 sec‐1) were modelled to simulate existing hydraulic conditions and hydraulic conditions simulating removal of a dam at the downstream boundary of the reach. Potential depth challenge zones were nonexistent for all low‐flow simulations of existing conditions for deeper‐bodied fishes. Increasing flows for existing conditions and removal of the dam under all flow conditions increased the number and size of potential velocity challenge zones, with the effects of zones being more pronounced for smaller species. The two‐dimensional CFD–HSI model has utility in demonstrating gross effects of flow and hydraulic alteration, but may not be as precise a predictive tool as a three‐dimensional model. Passability of the potential challenge zones cannot be precisely quantified for two‐dimensional or three‐dimensional models due to untested assumptions and incomplete data on fish swimming performance and behaviours. Published 2015. This article is a U.S. Government work and is in the public domain in the USA.
Laparoscopic Management of Choledochal Cyst‐Technical Modifications and Outcome Analysis
Authors: Senthilnathan Palanisamy , Patel Nikunj D. , Nair Arun S. , Nalankilli V. P. , Vijay Anand , Palanivelu Chinnusamy
Published: June 2015

Background

Choledochal cyst (CDC) is a well described albeit rare clinical entity. Complete cyst excision with biliary‐enteric reconstruction is the recommended treatment for Todani type I, II, and IVA cysts to prevent complications. The aim of this study is to evaluate outcomes of laparoscopic CDC excision from a tertiary care center.

Methods

This is a retrospective analysis of prospectively collected data of 110 patients who underwent laparoscopic cyst excision and biliary‐enteric reconstruction for CDC type I and IVA from 1998 to 2013.

Results

Out of 110 patients, 55 were children (<16 years) and 55 were adults (>16 years) with mean age 21.19 ± 17.75 years and male:female ratio of 1:2.14. Abdominal pain was the most common presenting symptom (59.09 %). Surprisingly, 32.73 % of adults presented with incidentally detected cyst. Type I cyst was the most common (71.82 %) with mean size of 4.67 ± 1.59 cm. Blood loss (56.0 ± 16.62 vs. 76.55 ± 26.61 ml) and operative time (199.8 ± 44.66 vs. 251.6 ± 54.25 min) were significantly low in pediatric group. Three adults required conversion. Overall complication rate was 10 %. Re‐exploration rate was 1.81 % with one patient died post‐operatively. Mean hospital stay was significantly low in children (5.9 ± 1.39 vs. 7.0 ± 2.66 days). Median follow‐up was 60 months (8–110). Cholangitis developed in six patients with three having anastomotic stricture requiring intervention.

Conclusion

Laparoscopic excision of CDC is safe and feasible. Surgery should be performed early as outcomes are better in pediatric age as compared to adults.
Predictors of the Effectiveness of Prophylactic Drains After Hepatic Resection
Authors: Bekki Yuki , Yamashita Yo‐ichi , Itoh Shinji , Harimoto Norifumi , Shirabe Ken , Maehara Yoshihiko
Published: June 2015

Background

Randomized clinical trials have demonstrated the limited efficacy of prophylactic drains following hepatic resection. However, many surgeons still insist on using prophylactic drains. This study was designed to identify patients who require prophylactic drains to manage or monitor postoperative complications after hepatic resection.

Methods

Data were retrospectively collected from 316 patients who underwent hepatic resection and received a prophylactic drain. The patients were divided into two groups according to whether the drain was used to manage or monitor the following postoperative complications: bile leakage (prophylactic drains were used to monitor and treat bile leakage) and postoperative hemorrhage (the drainage fluid was macroscopically bloody and required drain fluid blood counts and monitoring to assess the need for transfusion or reoperation). The results were then validated in a separate cohort of 101 patients.

Results

In 25/316 patients (7.9 %), the prophylactic drains were clinically effective, being used to manage bile leakage in 18 patients and hemorrhage in 8. Intraoperative bile leakage (P = 0.021) and long operation time (≥360 min) (P = 0.017) were independent predictors of bile leakage. Intraoperative blood loss (≥650 ml) (P = 0.0009) was an independent predictor of hemorrhage. In the subsequent 101 patients, prophylactic drains were clinically effective in patients with one of these predictors with sensitivity, specificity, and false‐negative rates of 88.9, 62.0, and 1.7 %, respectively.

Conclusion

A prophylactic drain should be considered following hepatic resection for patients with intraoperative bile leakage, operation time of ≥360 min, or blood loss of ≥650 ml.
The response of three Fagus sylvatica L. provenances to water availability at different soil depths
Authors: Baudis Mathias , Premper Thomas , Welk Erik , Bruelheide Helge
Published: June 2015

Current climate change scenarios predict changes in precipitation patterns resulting in a longer and more intensive droughts. These changes pose a challenge for Fagus sylvatica as the most common European deciduous tree species. We asked how different genotypes respond to drought conditions and paid particular attention to how soil moisture availability can be manipulated. We established a tube technique that allowed to add water horizontally at different rooting depths, which allowed to measure water contents and to observe root growth along the full length of 1‐m deep tubes. Three F. sylvatica provenances were compared in their response to different depth of water supply with respect to growth, leaf stomatal conductance as well as root and leaf traits. There were short‐lasting differences between the watering regimes in soil water content and depth of soil moisture maxima. Adding water to depths of 30–60 cm resulted in reduced leaf stomatal conductance and lower survival but increased root tip growth rates compared to watering the tubes at 10–20 cm. There were differences between the three provenances for specific leaf area and stem dry mass, which however, were independent of the watering regime and did not support the idea of local adaptation to drought of populations from dry or moist origins. The findings indicate that differences between provenances might have been caused by environmental factors other than drought. Technically, we demonstrated the high potential of using the tube technique for a fine‐tuned manipulation of soil moisture in the rooting space.
On fast trust region methods for quadratic models with linear constraints
Authors: Powell M. J. D.
Published: June 2015

Quadratic models

$$Q_k ( \underline{x}), \underline{x}\in \mathcal{R}^n$$

Q
k

(

x
̲

)

,

x
̲

∈

R

n

, of the objective function

$$F ( \underline{x}), \underline{x}\in \mathcal{R}^n$$

F

(

x
̲

)

,

x
̲

∈

R

n

, are used by many successful iterative algorithms for minimization, where k is the iteration number. Given the vector of variables

$$\underline{x}_k \in \mathcal{R}^n$$

x
̲

k

∈

R

n

, a new vector

$$\underline{x}_{k+1}$$

x
̲

k
+
1

may be calculated that satisfies

$$Q_k ( \underline{x}_{k+1} ) < Q_k ( \underline{x}_k )$$

Q
k

(

x
̲

k
+
1

)

<

Q
k

(

x
̲

k

)

, in the hope that it provides the reduction

$$F ( \underline{x}_{k+1} ) < F ( \underline{x}_k )$$

F

(

x
̲

k
+
1

)

<
F

(

x
̲

k

)

. Trust region methods include a bound of the form

$$\Vert \underline{x}_{k+1} - \underline{x}_k \Vert \le \Delta _k$$

‖

x
̲

k
+
1

-

x
̲

k

‖
≤

Δ
k

. Also we allow general linear constraints on the variables that have to hold at

$$\underline{x}_k$$

x
̲

k

and at

$$\underline{x}_{k+1}$$

x
̲

k
+
1

. We consider the construction of

$$\underline{x}_{k+1}$$

x
̲

k
+
1

, using only of magnitude

$$n^2$$

n
2

operations on a typical iteration when n is large. The linear constraints are treated by active sets, which may be updated during an iteration, and which decrease the number of degrees of freedom in the variables temporarily, by restricting

$$\underline{x}$$

x
̲

to an affine subset of

$$\mathcal{R}^n$$

R

n

. Conjugate gradient and Krylov subspace methods are addressed for adjusting the reduced variables, but the resultant steps are expressed in terms of the original variables. Termination conditions are given that are intended to combine suitable reductions in

$$Q_k ( \cdot )$$

Q
k

(
·
)

with a sufficiently small number of steps. The reason for our work is that

$$\underline{x}_{k+1}$$

x
̲

k
+
1

is required in the LINCOA software of the author, which is designed for linearly constrained optimization without derivatives when there are hundreds of variables. Our studies go beyond the final version of LINCOA, however, which employs conjugate gradients with termination at the trust region boundary. In particular, we find that, if an active set is updated at a point that is not the trust region centre, then the Krylov method may terminate too early due to a degeneracy. An extension to the conjugate gradient method for searching round the trust region boundary receives attention too, but it was also rejected from LINCOA, because of poor numerical results. The given techniques of LINCOA seem to be adequate in practice.
The Current State of Dance Micro and Macro Policies in Brazil
Authors: Matos Lúcia
Published: June 2015

Cultural policies, understood as acts of intervention, not only from the State, but also from social groups and institutions, trigger devices that highlight the complexity of the cultural system and power relationships. These acts, developed in a participatory manner, can contribute to the global re-politicization of collective life.

Regarding Brazil, we can assert the search for common spaces has grown in importance under president Luiz Inácio Lula da Silva's administration (2003–2010), when cultural policies suffered a significant change with the implementation of an inclusive and participatory model. This led to sectorial policies and the creation of public spaces for the representation of civil society. The field of dance took an active role in this process through its associations and regional forums, leading to the creation of a Dance Sectorial Collegiate and a Dance Federal Plan.

Despite some progress that has been made, cultural policies in Brazil are still under the strong influence of a neoliberal approach, which centers its efforts in economic development with a focus on public funding to culture and the creation of funding laws. A participative construction of public policy for dance would be based on agreements between civil society and government, going beyond the financing of arts through grants. The area of dance in Brazil needs structuring programs and actions that would collaborate with the organizational and productive modes of people and groups that are working to develop the area. Thus, this paper discusses cultural policies of dance by pointing out the consequences of “fast-cult” dance production and identifies spaces of resistance and micro-politics, generated by Brazilian artists who are seeking sustainable development and collaborative modes of production in dance.
Bourdieu and the dead end of reflexivity: On the impossible task of locating the subject
Authors: KNAFO SAMUEL
Published: June 2015

This article examines recent attempts by International Relations (IR) scholars to flesh out a reflexive approach inspired by the work of Pierre Bourdieu. The French sociologist pioneered the idea of turning the tools of sociology onto oneself in order to apply the same grid of social analysis to the object and subject of scholarship. This represents the culmination of a long tradition of seeking to understand from where one speaks and grasp our subjective biases through reflexive means. But as I argue Bourdieu – like most reflexive scholars – largely overestimated his ability to grasp his own subject position. For he assumed he could be objective about the very thing he had the least reasons to be objective about: himself. Instead of bending over backwards in this way and directly take the subject into account, I then propose to rearticulate the problematic of reflexivity by going back to a more classic concern with the question of alienation. Through a detailed critique of Bourdieu’s reflexive approach and the ways in which it was received in IR, I set out a series of principles to reconfigure the agenda of reflexivity and offer a platform for a proper methodological alternative to positivism.
On improving robot image-based visual servoing based on dual-rate reference filtering control strategy
Authors: Solanes J. Ernesto , Muñoz-Benavent Pau , Girbés Vicent , Armesto Leopoldo , Tornero Josep
Published: June 2015

It is well known that the use of multi-rate control techniques have improved the performance of many systems in general, and robotic systems, in particular. The main contribution of this paper is the generalization of the Reference Filtering control strategy from a dual-rate point of view, improving its inherent properties by overcoming the problem of sensor latency. In the paper, we discuss and analyze the improvements introduced by the novel dual-rate reference filtering control strategy in terms of convergence time, reachability and robustness. More specifically, we discuss the capability to solve positioning tasks, when hardware limitations are present with large sampling rates. In addition, a comparison is made between the single-rate and the proposed dual-rate control strategies to prove the advantages of the latter approach. A complete set-up has been prepared for validation, including a six degree of freedom (DOF) industrial manipulator, a smart camera and embedded hardware used as a high level controller.
Dual-band 3-way power divider and combiner based on CRLH-TLs
Authors: Bemani Mohammad , Nikmehr Saeid
Published: June 2015

In this paper, by using composite right and left handed transmission lines and non-radiating CRLH-TLs, a dual-band 3-way series power divider (SPD) is presented. The proposed dual-band divider is designed and fabricated on an inexpensive FR4 substrate of thickness h = 0.79 mm and a relative dielectric constant of εr = 4.4 to work at 0.915 and 2.440 GHz. Also, in order to improve the isolation characteristics of this divider, three isolation resistors are implemented among output ports. Derived formulas are presented in details. The dual-band nature of the designed SPD, good input return loss, as well as equal power split among the three output ports, flexibility of spacing the output ports arbitrarily apart, and easy integration with planar devices make the proposed divider well suited for feeding many dual-band microwave circuits, such as multipliers, mixers, and planar array antennas. In addition, due to its excellent return-loss at the output ports and its high isolation, the proposed divider in this paper can be used as a power combiner.
ICAM-1 suppresses tumor metastasis by inhibiting macrophage M2 polarization through blockade of efferocytosis
Authors: Yang M , Liu J , Piao C , Shao J , Du J
Published: June 2015

Efficient clearance of apoptotic cells (efferocytosis) can profoundly influence tumor-specific immunity. Tumor-associated macrophages are M2-polarized macrophages that promote key processes in tumor progression. Efferocytosis stimulates M2 macrophage polarization and contributes to cancer metastasis, but the signaling mechanism underlying this process is unclear. Intercellular cell adhesion molecule-1 (ICAM-1) is a transmembrane glycoprotein member of the immunoglobulin superfamily, which has been implicated in mediating cell–cell interaction and outside-in cell signaling during the immune response. We report that ICAM-1 expression is inversely associated with macrophage infiltration and the metastasis index in human colon tumors by combining Oncomine database analysis and immunohistochemistry for ICAM-1. Using a colon cancer liver metastasis model in ICAM-1-deficient (ICAM-1−/−) mice and their wild-type littermates, we found that loss of ICAM-1 accelerated liver metastasis of colon carcinoma cells. Moreover, ICAM-1 deficiency increased M2 macrophage polarization during tumor progression. We further demonstrated that ICAM-1 deficiency in macrophages led to promotion of efferocytosis of apoptotic tumor cells through activation of the phosphatidylinositol 3 kinase/Akt signaling pathway. More importantly, coculture of ICAM-1−/− macrophages with apoptotic cancer cells resulted in an increase of M2-like macrophages, which was blocked by an efferocytosis inhibitor. Our findings demonstrate a novel role for ICAM-1 in suppressing M2 macrophage polarization via downregulation of efferocytosis in the tumor microenvironment, thereby inhibiting metastatic tumor progression.
A novel germline mutation in a patient with nevoid basal cell carcinoma syndrome showing cystic lesion in the lung
Authors: Miyata Ryo , Kurosawa Manabu , Sato Masaaki , Kono Tomoya , Takubo Yasutaka , Okai Shinsaku , Yamada Keisuke , Shinkura Reiko , Date Hiroshi , Matsuda Fumihiko
Published: June 2015

Nevoid basal cell carcinoma syndrome (NBCCS) manifests multiple defects involving the skin, endocrine and nervous systems, eyes and bones. Mutations in the patched homologue 1 (PTCH1) gene are the underlying causes of NBCCS, leading to aberrant cell proliferation through constitutive activation of the hedgehog signaling pathway. We identified a novel frameshift mutation (c.1207dupT) of PTCH1 in a NBCCS patient, which might explain multiple cystic lesions and neoplastic growth in the patient.
Initial assembly steps of a translocase for folded proteins
Authors: Blümmel Anne-Sophie , Haag Laura A. , Eimer Ekaterina , Müller Matthias , Fröbel Julia
Published: June 2015

The so-called Tat (twin-arginine translocation) system transports completely folded proteins across cellular membranes of archaea, prokaryotes and plant chloroplasts. Tat-directed proteins are distinguished by a conserved twin-arginine (RR-) motif in their signal sequences. Many Tat systems are based on the membrane proteins TatA, TatB and TatC, of which TatB and TatC are known to cooperate in binding RR-signal peptides and to form higher-order oligomeric structures. We have now elucidated the fine architecture of TatBC oligomers assembled to form closed intramembrane substrate-binding cavities. The identification of distinct homonymous and heteronymous contacts between TatB and TatC suggest that TatB monomers coalesce into dome-like TatB structures that are surrounded by outer rings of TatC monomers. We also show that these TatBC complexes are approached by TatA protomers through their N-termini, which thereby establish contacts with TatB and membrane-inserted RR-precursors.
γ-secretase directly sheds the survival receptor BCMA from plasma cells
Authors: Laurent Sarah A. , Hoffmann Franziska S. , Kuhn Peer-Hendrik , Cheng Qingyu , Chu Yuanyuan , Schmidt-Supprian Marc , Hauck Stefanie M. , Schuh Elisabeth , Krumbholz Markus , Rübsamen Heike , Wanngren Johanna , Khademi Mohsen , Olsson Tomas , Alexander Tobias , Hiepe Falk , Pfister Hans-Walter , Weber Frank , Jenne Dieter , Wekerle Hartmut , Hohlfeld Reinhard , Lichtenthaler Stefan F. , Meinl Edgar
Published: June 2015

Survival of plasma cells is regulated by B-cell maturation antigen (BCMA), a membrane-bound receptor activated by its agonist ligands BAFF and APRIL. Here we report that γ-secretase directly cleaves BCMA, without prior truncation by another protease. This direct shedding is facilitated by the short length of BCMA’s extracellular domain. In vitro, γ-secretase reduces BCMA-mediated NF-κB activation. In addition, γ-secretase releases soluble BCMA (sBCMA) that acts as a decoy neutralizing APRIL. In vivo, inhibition of γ-secretase enhances BCMA surface expression in plasma cells and increases their number in the bone marrow. Furthermore, in multiple sclerosis, sBCMA levels in spinal fluid are elevated and associated with intracerebral IgG production; in systemic lupus erythematosus, sBCMA levels in serum are elevated and correlate with disease activity. Together, shedding of BCMA by γ-secretase controls plasma cells in the bone marrow and yields a potential biomarker for B-cell involvement in human autoimmune diseases.
Photogated humidity-driven motility
Authors: Zhang Lidong , Liang Haoran , Jacob Jolly , Naumov Panče
Published: June 2015

Hygroinduced motion is a fundamental process of energy conversion that is essential for applications that require contactless actuation in response to the day–night rhythm of atmospheric humidity. Here we demonstrate that mechanical bistability caused by rapid and anisotropic adsorption and desorption of water vapour by a flexible dynamic element that harnesses the chemical potential across very small humidity gradients for perpetual motion can be effectively modulated with light. A mechanically robust material capable of rapid exchange of water with the surroundings is prepared that undergoes swift locomotion in effect to periodic shape reconfiguration with turnover frequency of <150 min−1. The element can lift objects ∼85 times heavier and can transport cargos ∼20 times heavier than itself. Having an azobenzene-containing conjugate as a photoactive dopant, this entirely humidity-driven self-actuation can be controlled remotely with ultraviolet light, thus setting a platform for next-generation smart biomimetic hybrids.
Initial step-up treatment changes in asthmatic children already prescribed inhaled corticosteroids: a historical cohort study
Authors: Turner Steve W , Richardson Kathryn , Burden Annie , Thomas Mike , Murray Clare , Price David
Published: June 2015

Background:

When standard doses of inhaled corticosteroids (ICS) fail to control symptoms in children aged >4 years, guidelines recommend the addition of a long-acting β2-agonist (LABA), with other treatment options being available if symptoms persist.

Aims:

To determine the proportion of initial ‘step-up’ episodes where LABAs were prescribed and to describe characteristics of individuals not stepped up with LABA.

Methods:

Between 1999 and 2011, initial step-up episodes from ICS monotherapy were identified in children aged 5–12 years with asthma and in receipt of ICS. Data sources were the Clinical Practice Research Datalink and Optimum Patient Care Research Database.

Results:

Initial step-up episodes were identified in 10,793 children. ICS dose was increased in 6,252 children (58%), LABA was introduced in 3,436 (32%; including 1,107 where fixed dose combination inhaler (FDC) replaced the ICS inhaler), and leukotriene receptor antagonist (LTRA) was added in 1,105 (10%). Compared with children stepped up to any LABA, others were younger and prescribed lower doses of ICS and reliever medication. ICS dose increase was more likely in obese children and LTRA prescribing was more likely in children with rhinitis and in receipt of antibiotics. Compared with FDC, step-up to separate LABA inhaler was more likely in younger, obese children who were using less oral steroids.

Conclusions:

One-third of initial step-up episodes in children with asthma treated with ICS are to add LABA. Different characteristics of children prescribed therapies other than LABA suggest that prescribers tailor treatment in some clinical settings.
Decoherence control by quantum decoherence itself
Authors: Roszak Katarzyna , Filip Radim , Novotný Tomáš
Published: June 2015

We propose a general approach of protecting a two-level system against decoherence via quantum engineering of non-classical multiple superpositions of coherent states in a non-Markovian reservoir. The scheme surprisingly only uses the system-environment interaction responsible for the decoherence and projective measurements of the two-level system. We demonstrate the method on the example of an excitonic qubit in self-assembled semiconductor quantum dots coupled to the super-Ohmic reservoir of acoustic phonons.
Clinical application of clustered-AChR for the detection of SNMG
Authors: Zhao Guang , Wang Xiaoqing , Yu Xiaowen , Zhang Xiutian , Guan Yangtai , Jiang Jianming
Published: June 2015

Myasthenia gravis (MG) is an autoantibody-mediated disease of the neuromuscular junction (NMJ). However, accumulating evidence has indicated that MG patients whose serum anti-acetylcholine receptor (AChR) antibodies are not detectable (serumnegative MG; SNMG) in routine assays share similar clinical features with anti-AChR antibody-positive MG patients. We hypothesized that SNMG patients would have low-affinity antibodies to AChRs that would not be detectable using traditional methods but that might be detected by binding to AChR on the cell membrane, particularly if they were clustered at the high density observed at the NMJ. We expressed AChR subunits with the clustering protein rapsyn (an AChR-associated protein at the synapse) in human embryonic kidney (HEK) cells and we tested the binding of the antibodies using immunofluorescence. With this approach, AChR antibodies to rapsyn-clustered AChR could be detected in the sera from 45.83% (11/24) of SNMG patients, as confirmed with fluorescence-activated cell sorting (FACS). This was the first application in China of cell-based AChR antibody detection. More importantly, this sensitive (and specific) approach could significantly increase the diagnosis rate of SNMG.
Total and Proteinase K-Resistant α-Synuclein Levels in Erythrocytes, Determined by their Ability to Bind Phospholipids, Associate with Parkinson’s Disease
Authors: Abd-Elhadi Suaad , Honig Asaf , Simhi-Haham Dganit , Schechter Meir , Linetsky Eduard , Ben-Hur Tamir , Sharon Ronit
Published: June 2015

A marker for diagnosis of Parkinson’s disease (PD), which reflects on the occurrence of peripheral pathogenic mechanisms, would potentially improve therapy. The significance of α-Synuclein (α-Syn) expression in red blood cells (RBC) is currently unclear. Here we investigated whether RBC’s-expressed α-Syn may associate with PD. To this aim, we determined the levels of total and proteinase K-resistant α-Syn in samples of packed red blood cells (PRBCs). Twenty-one individuals with PD at various disease stages and 15 healthy controls, with similar demographic features, were recruited to this study. α-Syn levels were determined by their biochemical property to bind phospholipids, using a phospholipid-ELISA assay. A significantly lower ratio of total-to-proteinase K-resistant α-Syn levels was detected in PD patients than in the healthy control group. However, there was considerable overlap between the two groups. Suggesting a need for additional markers to be tested in combination with α-Syn levels. To the best of our knowledge, this is the first evidence for an association between RBCs-expressed α-Syn and pathogenic mechanisms involved in PD.
Ablation of retinal ciliopathy protein RPGR results in altered photoreceptor ciliary composition
Authors: Rao Kollu N. , Li Linjing , Anand Manisha , Khanna Hemant
Published: June 2015

Cilia regulate several developmental and homeostatic pathways that are critical to survival. Sensory cilia of photoreceptors regulate phototransduction cascade for visual processing. Mutations in the ciliary protein RPGR (retinitis pigmentosa GTPase regulator) are a prominent cause of severe blindness disorders due to degeneration of mature photoreceptors. However, precise function of RPGR is still unclear. Here we studied the involvement of RPGR in ciliary trafficking by analyzing the composition of photoreceptor sensory cilia (PSC) in Rpgrko retina. Using tandem mass spectrometry analysis followed by immunoblotting, we detected few alterations in levels of proteins involved in proteasomal function and vesicular trafficking in Rpgrko PSC, prior to onset of degeneration. We also found alterations in the levels of high molecular weight soluble proteins in Rpgrko PSC. Our data indicate RPGR regulates entry or retention of soluble proteins in photoreceptor cilia but spares the trafficking of key structural and phototransduction-associated proteins. Given a frequent occurrence of RPGR mutations in severe photoreceptor degeneration due to ciliary disorders, our results provide insights into pathways resulting in altered mature cilia function in ciliopathies.
Comparative Assessment of Transmission-Blocking Vaccine Candidates against Plasmodium falciparum
Authors: Kapulu M. C. , Da D. F. , Miura K. , Li Y , Blagborough A. M. , Churcher T. S. , Nikolaeva D. , Williams A. R. , Goodman A. L. , Sangare I. , Turner A. V. , Cottingham M. G. , Nicosia A. , Straschil U. , Tsuboi T. , Gilbert S. C. , Long Carole A. , Sinden R. E. , Draper S. J. , Hill A. V. S. , Cohuet A. , Biswas S.
Published: June 2015

Malaria transmission-blocking vaccines (TBVs) target the development of Plasmodium parasites within the mosquito, with the aim of preventing malaria transmission from one infected individual to another. Different vaccine platforms, mainly protein-in-adjuvant formulations delivering the leading candidate antigens, have been developed independently and have reported varied transmission-blocking activities (TBA). Here, recombinant chimpanzee adenovirus 63, ChAd63 and modified vaccinia virus Ankara, MVA, expressing AgAPN1, Pfs230-C, Pfs25 and Pfs48/45 were generated. Antibody responses primed individually against all antigens by ChAd63 immunization in BALB/c mice were boosted by the administration of MVA expressing the same antigen. These antibodies exhibited a hierarchy of inhibitory activity against the NF54 laboratory strain of P. falciparum in Anopheles stephensi mosquitoes using the standard membrane feeding assay (SMFA), with anti-Pfs230-C and anti-Pfs25 antibodies giving complete blockade. The observed rank order of inhibition was replicated against P. falciparum African field isolates in A. gambiae in direct membrane feeding assays (DMFA). TBA achieved was IgG concentration dependent. This study provides the first head-to-head comparative analysis of leading antigens using two different parasite sources in two different vector species and can be used to guide selection of TBVs for future clinical development using the viral-vectored delivery platform.
Estimating the anomalous diffusion exponent for single particle tracking data with measurement errors - An alternative approach
Authors: Burnecki Krzysztof , Kepten Eldad , Garini Yuval , Sikora Grzegorz , Weron Aleksander
Published: June 2015

Accurately characterizing the anomalous diffusion of a tracer particle has become a central issue in biophysics. However, measurement errors raise difficulty in the characterization of single trajectories, which is usually performed through the time-averaged mean square displacement (TAMSD). In this paper, we study a fractionally integrated moving average (FIMA) process as an appropriate model for anomalous diffusion data with measurement errors. We compare FIMA and traditional TAMSD estimators for the anomalous diffusion exponent. The ability of the FIMA framework to characterize dynamics in a wide range of anomalous exponents and noise levels through the simulation of a toy model (fractional Brownian motion disturbed by Gaussian white noise) is discussed. Comparison to the TAMSD technique, shows that FIMA estimation is superior in many scenarios. This is expected to enable new measurement regimes for single particle tracking (SPT) experiments even in the presence of high measurement errors.
ZrO2nanoparticles labeled via a native protein corona: detection by fluorescence microscopy and Raman microspectroscopy in rat lungs
Authors: Silge Anja , Bräutigam Katharina , Bocklitz Thomas , Rösch Petra , Vennemann Antje , Schmitz Inge , Popp Jürgen , Wiemann Martin
Published: June 2015

Raman microspectroscopy was applied to confirm the stability of a protein-based adsorptive labeling of ZrO2NP inside the rat lung up to 3 d post application.
A simple approach to improve the electrocatalytic properties of commercial Pt/C
Authors: Pearson Andrew , O'Mullane Anthony P.
Published: June 2015

Decoration of commercial Pt/C with Au via a simple solution process to improve electrocatalytic ethanol oxidation.
Unravelling the structure of the C60 and p-But-calix[8]arene complex
Authors: Chen Xianjue , Boulos Ramiz A. , Slattery Ashley D. , Atwood Jerry L. , Raston Colin L.
Published: June 2015

The structure of the C60 and p-But-calix[8]arene complex has been reinvestigated, showing an unprecedented continuous layered tetragonal array of fullerenes encapsulated by calixarenes.
Organocatalysts with carbon-centered activity for CO2 reduction with boranes
Authors: Yang Yanxin , Xu Maotong , Song Datong
Published: June 2015

We report two C/H/N-only organocatalysts with carbon-centered reactivity for CO2 reduction to methanol.
Electrocatalytic conversion of CO2 to produce solar fuels in electrolyte or electrolyte-less configurations of PEC cells
Authors: Ampelli C. , Genovese C. , Marepally B. C. , Papanikolaou G. , Perathoner S. , Centi G.
Published: June 2015

The electrocatalytic reduction of CO2 is studied on a series of electrodes (based on Cu, Co, Fe and Pt metal nanoparticles deposited on carbon nanotubes or carbon black and then placed at the interface between a Nafion membrane and a gas-diffusion-layer electrode) on two types of cells: one operating in the presence of a liquid bulk electrolyte and the other in the absence of the electrolyte (electrolyte-less conditions). The results evidence how the latter conditions allow productivity of about one order of magnitude higher and how to change the type of products formed. Under electrolyte-less conditions, the formation of >C2 products such as acetone and isopropanol is observed, but not in liquid-phase cell operations on the same electrodes. The relative order of productivity in CO2 electrocatalytic reduction in the series of electrodes investigated is also different between the two types of cells. The implications of these results in terms of possible differences in the reaction mechanism are commented on, as well as in terms of the design of photoelectrocatalytic (PEC) solar cells.
The influence of dispersed phases on polyamide/ZIF-8 nanofiltration membranes for dye removal from water
Authors: Wang Luying , Fang Manquan , Liu Jing , He Jing , Deng Lihong , Li Jiding , Lei Jiandu
Published: June 2015

The influence of different dispersed phases on PA/ZIF-8 membrane properties was investigated, and the PA/ZIF-8(B) membrane (ZIF-8 dispersed in both the aqueous and organic phases) exhibited the best performance for dye removal by nanofiltration.
Electrochemical exfoliation of graphite for producing graphene using saccharin
Authors: M. K. Punith Kumar , Shanthini S. , Srivastava Chandan
Published: June 2015

TEM bright field images of graphene samples synthesized at 2 V, 4 V, 6 V, 8 V and 10 V intercalation potential using saccharin.
Dual channel selective fluorescent detection of Al3+ and PPi in mixed aqueous media: DFT studies and cell imaging applications
Authors: Alam Rabiul , Mistri Tarun , Bhowmick Rahul , Katarkar Atul , Chaudhuri Keya , Ali Mahammad
Published: June 2015

A new, easily synthesizable chemosensor, DFC-EN-p-Ph-NO2, acts as a dual channel (colori- and fluorimetric) sensor for Al3+ and PPi.
Reduction-assisted sintering of micron-sized copper powders at low temperature by ethanol vapor
Authors: Wu Cyuan-Jhang , Cheng Shao-Liang , Sheng Yu-Jane , Tsao Heng-Kwong
Published: June 2015

The low temperature sintering of micron-sized Cu powders is achieved by ethanol vapor annealing.
Superior As(iii) removal performance of hydrous MnOOH nanorods from water
Authors: Guo Song , Sun Wuzhu , Yang Weiyi , Li Qi , Shang Jian Ku
Published: June 2015

MnOOH nanorods demonstrated a superior As(iii) removal performance with an adsorption capacity over 431.2 mg g−1from water at pH 7.
Microscopic segregation of hydrophilic ions in critical binary aqueous solvents
Authors: Witala Monika , Nervo Roberto , Konovalov Oleg , Nygård Kim
Published: June 2015

We report direct experimental observation of microscopic segregation of hydrophilic ions in a critical aqueous binary mixture.
Dual channel time‐to‐digital converter module with 10 ps resolution and 320 ns full scale range
Authors: Tamborini D. , Portaluppi D. , Villa F. , Zappa F.
Published: June 2015

A dual‐channel time‐to‐digital converter (TDC) module designed to accurately measure time intervals with 10 ps resolution, about 21 ps root‐mean‐square (rms) precision and 125 fs rms differential nonlinearity, over a 320 ns full scale range and up to 4 Mconv/s per channel is presented. The module can also operate the two channels in parallel, as a single TDC converter, in order to improve timing performance to about 15.3 ps rms. A USB 2.0 interface provides the power supply and allows fast data transfer to a computer, where a dedicated software interface handles measurement data and plots. Because of the excellent timing performance, compact dimensions and low power consumption, the dual‐channel TDC module is suitable for advanced multi‐channel time measurements at the picosecond level.
Automatic quality assessment and optimisation of quadratic time–frequency representations
Authors: Malnar D. , Sucic V. , O'Toole J.M.
Published: June 2015

A fully automatic method for optimising the smoothed‐pseudo Wigner‐Ville distribution is presented. An alternative view on time–frequency representations (TFRs) through correlation intensity landscapes is offered, and the notion of wanted and unwanted correlations and their balance is introduced which is introduced as the measure of quality. The problem of optimising TFRs is then formulated as the cost function based on this measure. With the differential evolution algorithm as the solver, the method's performance is tested on synthetic and real‐life signals.
Pulsed gate bias control of GaN HEMTs to improve pulse‐to‐pulse stability in radar applications
Authors: Delprato J. , Delias A. , Medrel P. , Barataud D. , Campovecchio M. , Neveux G. , Martin A. , Bouysse P. , Nebus J.M. , Tolant C. , Eudeline P.
Published: June 2015

A significant improvement is demonstrated in the measured pulse‐to‐pulse stability of an S‐band 6 W GaN high electron mobility transistor (HEMT) power amplifier by generating an appropriate pulse of the gate bias and thus a warm‐up drain current just before each radio‐frequency (RF) pulse of a periodic and coherent radar burst. The amplitude and the width of this gate bias pulse preceding each periodic RF pulse of the burst are experimentally varied to investigate the trade‐off between the improvement of pulse‐to‐pulse stability and the total power‐added efficiency. Finally, this technique of synchronised warm‐up gate bias pulse demonstrated a 10 dB improvement of measured amplitude pulse‐to‐pulse stabilities to meet the critical stability requirement below −55 dB for the RF power amplifier.
Lift enhancement on spanwise oscillating flat-plates in low-Reynolds-number flows
Authors: Wang Shizhao , He Guowei , Zhang Xing
Published: June 2015

Numerical simulations are performed to study the influence of spanwise oscillations on the three-dimensional flows around low-aspect-ratio flat-plates at a low Reynolds number of 300. The harmonic spanwise oscillations of the plate are controlled by two parameters: the reduced frequency k and the dimensionless amplitude Ay. It is found that in a certain range of the parameter space (k, Ay), spanwise oscillations are effective in enhancing the average lift and augmenting the average lift-to-drag ratio. To elucidate the mechanism of lift enhancement due to the spanwise oscillations, the wake structures behind flat-plates with and without spanwise oscillations are compared. It is observed that the spanwise oscillation stabilizes the leading-edge vortex and presses it to a place very close to the upper surface. Since a leading-edge vortex corresponds to a low-pressure core, the stably attached leading-edge vortex benefits lift production. This lift-enhancement mechanism is also verified by using a simplified lift formula which links the lift force with the Lamb vector term. The imposed spanwise oscillation is found to enhance the vorticity transport along the spanwise direction, which in turn improves the stability of the leading-edge vortex. The results of this study provide new insight into the counterintuitive high-lift in the gliding flights of tree snakes.
Improved open-circuit voltage in Cu(In,Ga)Se2 solar cells with high work function transparent electrodes
Authors: Jäger Timo , Romanyuk Yaroslav E. , Bissig Benjamin , Pianezzi Fabian , Nishiwaki Shiro , Reinhard Patrick , Steinhauser Jérôme , Schwenk Johannes , Tiwari Ayodhya N.
Published: June 2015

Hydrogenated indium oxide (IOH) is implemented as transparent front contact in Cu(In,Ga)Se2 (CIGS) solar cells, leading to an open circuit voltage VOC enhanced by ∼20 mV as compared to reference devices with ZnO:Al (AZO) electrodes. This effect is reproducible in a wide range of contact sheet resistances corresponding to various IOH thicknesses. We present the detailed electrical characterization of glass/Mo/CIGS/CdS/intrinsic ZnO (i-ZnO)/transparent conductive oxide (TCO) with different IOH/AZO ratios in the front TCO contact in order to identify possible reasons for the enhanced VOC. Temperature and illumination intensity-dependent current-voltage measurements indicate that the dominant recombination path does not change when AZO is replaced by IOH, and it is mainly limited to recombination in the space charge region and at the junction interface of the solar cell. The main finding is that the introduction of even a 5 nm-thin IOH layer at the i-ZnO/TCO interface already results in a step-like increase in VOC. Two possible explanations are proposed and verified by one-dimensional simulations using the SCAPS software. First, a higher work function of IOH as compared to AZO is simulated to yield an VOC increase by 21 mV. Second, a lower defect density in the i-ZnO layer as a result of the reduced sputter damage during milder sputter-deposition of IOH can also add to a maximum enhanced VOC of 25 mV. Our results demonstrate that the proper choice of the front TCO contact can reduce the parasitic recombination and boost the efficiency of CIGS cells with improved corrosion stability.
Glass formation in a mixture of hard disks and hard ellipses
Authors: Xu Wen-Sheng , Duan Xiaozheng , Sun Zhao-Yan , An Li-Jia
Published: June 2015

We present an event-driven molecular dynamics study of glass formation in two-dimensional binary mixtures composed of hard disks and hard ellipses, where both types of particles have the same area. We demonstrate that characteristic glass-formation behavior appears upon compression under appropriate conditions in such systems. In particular, while a rotational glass transition occurs only for the ellipses, both types of particles undergo a kinetic arrest in the translational degrees of freedom at a single density. The translational dynamics for the ellipses is found to be faster than that for the disks within the same system, indicating that shape anisotropy promotes the translational motion of particles. We further examine the influence of mixture’s composition and aspect ratio on the glass formation. For the mixtures with an ellipse aspect ratio of k = 2, both translational and rotational glass transition densities decrease with increasing the disk concentration at a similar rate, and hence, the two glass transitions remain close to each other at all concentrations investigated. By elevating k, however, the rotational glass transition density diminishes at a faster rate than the translational one, leading to the formation of an orientational glass for the ellipses between the two transitions. Our simulations imply that mixtures of particles with different shapes emerge as a promising model for probing the role of particle shape in determining the properties of glass-forming liquids. Furthermore, our work illustrates the potential of using knowledge concerning the dependence of glass-formation properties on mixture’s composition and particle shape to assist in the rational design of amorphous materials.
Method of mechanical holding of cantilever chip for tip-scan high-speed atomic force microscope
Authors: Fukuda Shingo , Uchihashi Takayuki , Ando Toshio
Published: June 2015

In tip-scan atomic force microscopy (AFM) that scans a cantilever chip in the three dimensions, the chip body is held on the Z-scanner with a holder. However, this holding is not easy for high-speed (HS) AFM because the holder that should have a small mass has to be able to clamp the cantilever chip firmly without deteriorating the Z-scanner’s fast performance, and because repeated exchange of cantilever chips should not damage the Z-scanner. This is one of the reasons that tip-scan HS-AFM has not been established, despite its advantages over sample stage-scan HS-AFM. Here, we present a novel method of cantilever chip holding which meets all conditions required for tip-scan HS-AFM. The superior performance of this novel chip holding mechanism is demonstrated by imaging of the α3β3 subcomplex of F1-ATPase in dynamic action at ∼7 frames/s.
Self-assembly of tin wires via phase transformation of heteroepitaxial germanium-tin on germanium substrate
Authors: Wang Wei , Li Lingzi , Tok Eng Soon , Yeo Yee-Chia
Published: June 2015

This work demonstrates and describes for the first time an unusual strain-relaxation mechanism by the formation and self-assembly of well-ordered tin wires during the thermal annealing of epitaxial Ge0.83Sn0.17-on-Ge(001) substrate. Fully strained germanium-tin alloys (Ge0.83Sn0.17) were epitaxially grown on Ge(001) substrate by molecular beam epitaxy. The morphological and compositional evolution of Ge0.83Sn0.17 during thermal annealing is studied by atomic force microscopy, X-ray diffraction, transmission electron microscopy. Under certain annealing conditions, the Ge0.83Sn0.17 layer decomposes into two stable phases, and well-defined Sn wires that are preferentially oriented along two orthogonal ⟨100⟩ azimuths are formed. The formation of the Sn wires is related to the annealing temperature and the Ge0.83Sn0.17 thickness, and can be explained by the nucleation of a grain with Sn islands on the outer front, followed by grain boundary migration. The Sn wire formation process is found to be thermally activated, and an activation enthalpy (Ec) of 0.41 eV is extracted. This thermally activated phase transformation, i.e., 2D epitaxial layer to 3D wires, occurs via a mechanism akin to “cellular precipitation.” This synthesis route of Sn wires opens new possibilities for creation of nanoscale patterns at high-throughput without the need for lithography.