bluuebunny/crossref_metadata_2025 huggingface dataset:
Low-cost platinum-free counter electrode of La0.67Sr0.33MnO3 perovskite for efficient dye-sensitized solar cells
Authors: Zhong Yongfeng , Chen Peng , Yang Bo , Zuo Xueqin , Zhou Lei , Yang Xiao , Li Guang
Published: June 2015

In this work, the perovskite-type La0.67Sr0.33MnO3 (LSMO) oxide with perfect crystallinity was synthesized via sol-gel method and used as low-cost platinum-free counter electrodes (CEs) for dye-sensitized solar cell (DSSCs). The electrochemical characterizations indicate that LSMO electrode possesses excellent electrocatalytic activity for the I3− reduction and excellent electrochemical stability in I−/I3− electrolyte system. The DSSC based on this counter electrode achieves an energy conversion efficiency (η) of 6.62%, which approaches 92.6% of the level obtained by using Pt as CE (η = 7.15%). Theperovskite-type oxide is low-cost and can be massively produced via sol-gel method which is superior to the solvothermal method. This work makes an attempt to develop potential counter electrode materials in perovskite-type oxides, which can help reduce the cost of DSSCs and thereby encourage their fundamental research and commercial applications.
Systematic review of the Australian ‘bush-coconut’ genus Cystococcus (Hemiptera: Eriococcidae) uncovers a new species from Queensland
Authors: Semple Thomas L. , Gullan Penny J. , Hodgson Christopher J. , Hardy Nate B. , Cook Lyn G.
Published: June 2015

Australia houses some unusual biota (insects included), much of which is undescribed. Cystococcus Fuller (Hemiptera : Sternorrhyncha : Coccoidea : Eriococcidae) currently comprises two species, both of which induce galls exclusively on bloodwoods (Myrtaceae: Corymbia Hill & Johnson). These insects display sexual dichronism, whereby females give birth first to sons and then to daughters. Wingless first-instar females cling to their winged adult brothers and are carried out of the maternal gall when the males fly to find mates – a behaviour called intersexual phoresy. Here, we use data from two gene regions, as well as morphology and host-use of the insects, to assess the status of a previously undescribed species. We describe this newly recognised species as Cystococcus campanidorsalis, sp. nov. Semple, Cook & Hodgson, redescribe the two existing species – C. echiniformis Fuller and C. pomiformis (Froggatt), designate a lectotype for C. echiniformis, and provide the first descriptions of adult males, and nymphal males and females for the genus. We have also reinterpreted a key morphological character of the adult females. This paper provides a foundation for further work on the genus, which is widespread across northern Australia and could prove to be useful for studies on biogeography and bloodwood ecosystems. urn:lsid:zoobank.org:pub:3A9DC645-0CBC-48B0-8BD3-5ACC0E2130D1
Optimising the extraction of amorphous silica by NaOH from soils of temperate-humid climate
Authors: Georgiadis Anna , Sauer Daniela , Breuer Jörn , Herrmann Ludger , Rennert Thilo , Stahr Karl
Published: June 2015

This study focuses on optimising amorphous silica extraction from soils by using NaOH. Based on the results of this test series, a method for quantifying amorphous silica in soils from temperate-humid climate is proposed. All tests were carried out on materials of known composition (well-defined samples of feldspar, clay minerals, bio-opal, silica gel, and mixtures of these components) and on soil samples, to determine the optimum set of conditions, in terms of solid : solution ratio, temperature and extraction time, for dissolving amorphous silica without considerably attacking other solid silicon compounds.
A solution of 0.2 m NaOH almost completely extracted amorphous silica, and when applied at room temperature and a solid : solution ratio of 1 : 400, only slightly broke down crystalline Si compounds. The predictable and reproducible underestimation was considered more acceptable than the variable partial dissolution of silicates that occurs during extraction at higher temperatures. We therefore recommend using this method on soils from temperate-humid climate to estimate the amorphous Si fraction.
West African monsoon dynamics inferred from abrupt fluctuations of Lake Mega-Chad
Authors: Armitage Simon J. , Bristow Charlie S. , Drake Nick A.
Published: June 2015

Significance

North Africa was wetter 15,000–5,000 years ago than today, with wetlands and lakes formed in the Sahara due to an enhanced monsoon. We reconstruct the lake-level history of Lake Mega-Chad, when it was the largest African lake, and demonstrate that this humid period ended abruptly 5,000 years ago, indicating that the African monsoon exhibits a nonlinear response to insolation forcing. The northern basin of Lake Mega-Chad, currently the world’s greatest dust source, became dry around 1,000 years ago. Prior to that time dust output from the northern basin would have been limited, and suggestions that this dust plays an important role in fertilizing Atlantic and Amazonian ecosystems are either overstated or only true for the last thousand years.
Noradrenergic blockade stabilizes prefrontal activity and enables fear extinction under stress
Authors: Fitzgerald Paul J. , Giustino Thomas F. , Seemann Jocelyn R. , Maren Stephen
Published: June 2015

Significance

Posttraumatic stress disorder is characterized by a resistance to extinction learning and dysregulated signaling of the neurotransmitter norepinephrine. Previous research suggested the prelimbic and infralimbic subdivisions of the medial prefrontal cortex (mPFC) regulate fear expression and suppression, respectively. However, noradrenergic signaling in response to psychological stress may disrupt mPFC function, contributing to extinction deficits. Here we show, for the first time to our knowledge, that footshock stress dysregulates mPFC spike firing; this can be stabilized by propranolol, a β-noradrenergic receptor blocking drug, which in turn facilitates extinction when it normally fails. These findings suggest that propranolol may be a particularly effective adjunct to behavioral therapy soon after trauma, when stress is high, at least in part by normalizing prefrontal cortical function.
Notch1–STAT3–ETB
R
signaling axis controls reactive astrocyte proliferation after brain injury
Authors: LeComte Matthew D. , Shimada Issei S. , Sherwin Casey , Spees Jeffrey L.
Published: June 2015

Significance

We demonstrate a signaling axis that controls reactive astrogliosis after brain injury based on the Notch1 receptor, signal transducer and activator of transcription 3 (STAT3), and endothelin receptor type B (ETB
R
). Knowledge of the Notch1–STAT3–ETB
R
signaling axis provides fundamental insight into the signaling network that regulates reactive astrocyte proliferation after brain injury. In addition, we identify the first set of markers for prospective isolation of proliferative reactive astrocytes directly from injured CNS tissue (GLAST
+
/Jagged1
Hi
) and describe a unique method to generate large quantities of primary adult reactive astrocytes based on redifferentiation from reactive astrocyte-derived neural stem cells. These tools provide a powerful platform to map the signaling network that controls reactive astrogliosis.
Enzyme mechanism-based, oxidative DNA–protein cross-links formed with DNA polymerase β in vivo
Authors: Quiñones Jason L. , Thapar Upasna , Yu Kefei , Fang Qingming , Sobol Robert William , Demple Bruce
Published: June 2015

Significance

Oxidative DNA damage is a by-product of aerobic metabolism and various genotoxic agents, including many cancer therapy regimens. Important DNA lesions include 2-deoxyribonolactone (dL), a major type of oxidized abasic (AP) site. In addition to the cytotoxic and mutagenic effects of non-oxidized AP sites, dL poses another threat: in vitro, dL traps some DNA repair enzymes in covalent DNA–protein cross-links (DPC) via their AP lyase activity. A prime example is DNA polymerase β (Polβ), which is critical for base excision DNA repair. Here we show that oxidative Polβ-DPC form robustly during attempted DNA repair in mammalian cells treated with dL-inducing oxidants. Mammalian cells remove Polβ-DPC surprisingly rapidly by a mechanism dependent on proteasome activity. Their accumulation is toxic.
Triangulation of the neurocomputational architecture underpinning reading aloud
Authors: Hoffman Paul , Lambon Ralph Matthew A. , Woollams Anna M.
Published: June 2015

Significance

Reading is a critical linguistic skill, but understanding of its cognitive and neural bases is incomplete. Using functional MRI, we found reading-related activation in two areas of anterior temporal cortex, an area not previously associated with reading. Activation profiles of these sites were consistent with the predictions of computational reading models that ascribe a key role to semantic knowledge in reading words with irregular spellings. We also found individual differences in the reading neural network that were predicted by an independent measure of semantic reliance in reading. Such individual differences have been hypothesized on theoretical grounds to explain variation in reading abilities among neurodegenerative patients. Here we provide the first direct evidence, to our knowledge, for their existence in the healthy brain.
Active and widespread halogen chemistry in the tropical and subtropical free troposphere
Authors: Wang Siyuan , Schmidt Johan A. , Baidar Sunil , Coburn Sean , Dix Barbara , Koenig Theodore K. , Apel Eric , Bowdalo Dene , Campos Teresa L. , Eloranta Ed , Evans Mathew J. , DiGangi Joshua P. , Zondlo Mark A. , Gao Ru-Shan , Haggerty Julie A. , Hall Samuel R. , Hornbrook Rebecca S. , Jacob Daniel , Morley Bruce , Pierce Bradley , Reeves Mike , Romashkin Pavel , ter Schure Arnout , Volkamer Rainer
Published: June 2015

Significance

Our measurements show that tropospheric halogen chemistry has a larger capacity to destroy O
3
and oxidize atmospheric mercury than previously recognized. Halogen chemistry is currently missing in most global and climate models, and is effective at removing O
3
at altitudes where intercontinental O
3
transport occurs. It further helps explain the low O
3
levels in preindustrial times. Public health concerns arise from bioaccumulation of the neurotoxin mercury in fish. Our results emphasize that bromine chemistry in the free troposphere oxidizes mercury at a faster rate, and makes water-soluble mercury available for scavenging by thunderstorms. Naturally occurring bromine in air aloft illustrates global interconnectedness between energy choices affecting mercury emissions in developing nations and mercury deposition in, e.g., Nevada, or the southeastern United States.
Drug-eluting microarrays to identify effective chemotherapeutic combinations targeting patient-derived cancer stem cells
Authors: Carstens Matthew R. , Fisher Robert C. , Acharya Abhinav P. , Butterworth Elizabeth A. , Scott Edward , Huang Emina H. , Keselowsky Benjamin G.
Published: June 2015

Significance

Cancer research has relied on in vitro experiments with established cell lines to investigate the efficacy of chemotherapy drug panels, which limit clinical correlation. Targeting tumor-initiating cells could be a viable clinical strategy, but these cells are extremely rare, necessitating new methods for rapid and robust screening. We developed a miniaturized platform to investigate the chemosensitivity of patient-derived tumor-initiating cells using limited cell numbers. The miniature platform described herein represents, to our knowledge, the first demonstration of a cell patterning technique that combines the ability to release small molecule drugs, alone or in combination, to separate islands of cells. This device can be adopted in clinical and academic laboratories targeting cancer stem cell populations to tailor patient-specific chemotherapeutic treatment options.
A superarmored lobopodian from the Cambrian of China and early disparity in the evolution of Onychophora
Authors: Yang Jie , Ortega-Hernández Javier , Gerber Sylvain , Butterfield Nicholas J. , Hou Jin-bo , Lan Tian , Zhang Xi-guang
Published: June 2015

Significance

Paleozoic lobopodians constitute a diverse assemblage of worm-like organisms that are known from various exceptional fossil deposits and were among the earliest animals to develop skeletonized body parts for protection. Here, we describe
Collinsium ciliosum
gen. et sp. nov., an armored lobopodian from the early Cambrian Xiaoshiba Lagerstätte (South China).
Collinsium
belongs to an extinct clade of superarmored lobopodians characterized by supernumerary dorsal spines, and specialized limbs for filter feeding; collectively, these fossil taxa represent a well-defined group within the lineage leading to extant velvet worms (Onychophora). Despite their greater morphological variety and appendage complexity compared with other lobopodians and extant velvet worms,
Collinsium
and its close relatives embodied a unique, yet ultimately failed, autoecology during the Cambrian explosion.
FUS functions in coupling transcription to splicing by mediating an interaction between RNAP II and U1 snRNP
Authors: Yu Yong , Reed Robin
Published: June 2015

Significance

The protein fused-in-sarcoma (FUS) is mutated to cause the neurodegenerative disease amyotrophic lateral sclerosis, but its normal cellular role remains to be understood. Previous work showed that FUS associates with both RNA polymerase II (RNAP II) and the essential splicing factor U1 small nuclear ribonucleoprotein (snRNP). Here we were able to directly investigate the functional significance of these interactions using an in vitro system. We show that FUS is essential for the interaction between U1 snRNP and RNAP II and that FUS must be present during the RNAP II transcription reaction in order for splicing to occur. Together, these data indicate that FUS mediates an interaction between RNAP II and U1 snRNP, thereby physically and functionally coupling transcription to splicing.
The MYB36 transcription factor orchestrates Casparian strip formation
Authors: Kamiya Takehiro , Borghi Monica , Wang Peng , Danku John M. C. , Kalmbach Lothar , Hosmani Prashant S. , Naseer Sadaf , Fujiwara Toru , Geldner Niko , Salt David E.
Published: June 2015

Significance

Casparian strips play a critical role in sealing endodermal cells in the root to block uncontrolled extracellular uptake of nutrients and water. Building Casparian strips requires the construction of extracellular lignin structures that encircle cells within the cell wall and that are anchored to the plasma membranes of adjacent cells to form tight seals between them. The transcription factor we have discovered, and the set of genes it regulates, now provides us with the detailed “parts list” necessary to build Casparian strips. This finding has clear implications for better understanding the nature of tight cellular junctions in biology and also has practical implications of agricultural, offering the potential for improved water and nutrient use efficiencies and enhanced resistance to abiotic stresses.
O-glycans direct selectin ligands to lipid rafts on leukocytes
Authors: Shao Bojing , Yago Tadayuki , Setiadi Hendra , Wang Ying , Mehta-D’souza Padmaja , Fu Jianxin , Crocker Paul R. , Rodgers William , Xia Lijun , McEver Rodger P.
Published: June 2015

Significance

Leukocytes partition certain proteins into cholesterol- and sphingolipid-rich membrane regions (lipid rafts) that function as signaling platforms. Inflammatory stimuli cause leukocytes to elongate to form lamellipodia and uropods at opposite ends that facilitate migration. Many raft-associated proteins move to uropods. Proteins are typically thought to use their transmembrane and cytoplasmic domains to associate with rafts. Here, we found that some leukocyte adhesion proteins used carbohydrate modification (glycosylation) of their extracellular domains to associate with lipid rafts. These proteins required preassociation with rafts to transduce signals but, unexpectedly, not to move to uropods. These data define a mechanism for localizing proteins to critical membrane regions of leukocytes.
DDT-based indoor residual spraying suboptimal for visceral leishmaniasis elimination in India
Authors: Coleman Michael , Foster Geraldine M. , Deb Rinki , Pratap Singh Rudra , Ismail Hanafy M. , Shivam Pushkar , Ghosh Ayan Kumar , Dunkley Sophie , Kumar Vijay , Coleman Marlize , Hemingway Janet , Paine Mark J. I. , Das Pradeep
Published: June 2015

Significance

Visceral leishmaniasis (VL), also known as kala-azar, is a major parasitic disease on the Indian subcontinent, with 85% of the disease incidence in India. As with malaria, indoor residual spraying (IRS) can be used to control and, ultimately, eliminate VL as a public health problem. However, in India, widespread resistance to dichlorodiphenyltrichloroethane (DDT), the insecticide used, combined with poor quality assurance (QA) of IRS and limited entomological surveillance, is hindering the VL elimination effort. Here, we present entomological abundance and insecticide resistance data and data arising from QA of IRS to explore these issues and establish an evidence base for improving the Indian VL elimination program. Unless these issues are addressed, the South Asian VL elimination effort will fail.
Nuclear receptor Nurr1 agonists enhance its dual functions and improve behavioral deficits in an animal model of Parkinson’s disease
Authors: Kim Chun-Hyung , Han Baek-Soo , Moon Jisook , Kim Deog-Joong , Shin Joon , Rajan Sreekanth , Nguyen Quoc Toan , Sohn Mijin , Kim Won-Gon , Han Minjoon , Jeong Inhye , Kim Kyoung-Shim , Lee Eun-Hye , Tu Yupeng , Naffin-Olivos Jacqueline L. , Park Chang-Hwan , Ringe Dagmar , Yoon Ho Sup , Petsko Gregory A. , Kim Kwang-Soo
Published: June 2015

Significance

Parkinson’s disease (PD) is the most prevalent movement disorder with no available treatments that can stop or slow down the disease progress. Although the orphan nuclear receptor Nurr1 is a promising target for PD, it is thought to be a ligand-independent transcription factor and, so far, no small molecule has been identified that can bind to its ligand binding domain. Here, we established high throughput cell-based assays and successfully identified three Nurr1 agonists among FDA-approved drugs, all sharing an identical chemical scaffold. Remarkably, these compounds not only directly bind to Nurr1 but also ameliorate behavioral defects in a rodent model of PD. Thus, our study shows that Nurr1 could serve as a valid drug target for neuroprotective therapeutics of PD.
Role of RAG1 autoubiquitination in V(D)J recombination
Authors: Singh Samarendra K. , Gellert Martin
Published: June 2015

Significance

The immune system of vertebrates has to respond to a great variety of infectious agents. Its power to meet these challenges relies on the assembly of a diverse set of genes for antibodies and T-cell receptors from large arrays of gene segments. This genomic reshuffling, known as V(D)J recombination, is initiated by the RAG1 and RAG2 proteins working together to cut DNA at specific sites. In addition to its role in DNA cleavage, RAG1 is known to contain a ubiquitin ligase activity that attaches ubiquitin to itself, as well as other proteins. Here we show that ubiquitination of RAG1, which can be promoted by RAG1’s own ubiquitin ligase activity, is a powerful activator of the DNA cutting and recombination activity of RAG1/RAG2.
Deep Hooking and Postrelease Mortality of Two Australian Native Freshwater Fishes Angled from Rivers by using Natural Baits
Authors: Hall Karina C. , Broadhurst Matt K. , Cullis Brian R.
Published: June 2015

Deep hooking is one of the key causes of mortality among angled‐and‐released teleosts worldwide. We assessed the effects of natural baits and other variables on the frequency of deep hooking and postrelease mortality in two Australian native freshwater fishes that are classified as vulnerable or endangered: Golden Perch Macquaria ambigua and Freshwater Catfish Tandanus tandanus. Sixty‐one angled Golden Perch were released and monitored in individual submersible cages at their capture location or were held in shore‐based group tanks; of these fish, 97% were hooked with natural baits, 41% were deep hooked and had their lines cut, and 44% died. Of the Golden Perch that died, 70% were deep hooked, and hook location and two associated factors (hook removal and ease of handling) were identified as significant predictors of mortality. Mortality of Golden Perch was also significantly greater during the afternoon session on the first day of angling than during other sessions and days. In contrast, of the 98 Freshwater Catfish that were similarly angled with natural baits, only 9% ingested hooks and only 3% died, with no significant mortality factors identified. None of the control fish died. Interspecific differences in deep‐hooking frequency are discussed in relation to the significant influences of time of day (both species), angler experience (Freshwater Catfish), and river reach (Golden Perch) and the likely differences in mouth morphology and feeding mechanisms. The results indicate that anglers should refrain from using natural baits when fishing for Golden Perch so as to minimize deep hooking and postrelease mortality, which will ultimately help conserve and manage these stocks.
Yvh1 protein phosphatase is required for pre-autophagosomal structure formation after TORC1 inactivation
Authors: Yeasmin Akter M S T , Waliullah Talukdar Muhammad , Kondo Akihiro , Ushimaru Takashi
Published: June 2015

The pre-autophagosomal structure (PAS) is a putative site for autophagosome formation in budding yeast. Upon nutrient depletion or rapamycin treatment, target of rapamycin complex 1 (TORC1) becomes inactive, inducing PAS formation and autophagy. Here, we show that Yvh1 phosphatase is critical for PAS formation, but not autophagy induction, after TORC1 inactivation.
A stable microtubule array drives fission yeast polarity reestablishment upon quiescence exit
Authors: Laporte Damien , Courtout Fabien , Pinson Benoît , Dompierre Jim , Salin Bénédicte , Brocard Lysiane , Sagot Isabelle
Published: June 2015

Cells perpetually face the decision to proliferate or to stay quiescent. Here we show that upon quiescence establishment, Schizosaccharomyces pombe cells drastically rearrange both their actin and microtubule (MT) cytoskeletons and lose their polarity. Indeed, while polarity markers are lost from cell extremities, actin patches and cables are reorganized into actin bodies, which are stable actin filament–containing structures. Astonishingly, MTs are also stabilized and rearranged into a novel antiparallel bundle associated with the spindle pole body, named Q-MT bundle. We have identified proteins involved in this process and propose a molecular model for Q-MT bundle formation. Finally and importantly, we reveal that Q-MT bundle elongation is involved in polarity reestablishment upon quiescence exit and thereby the efficient return to the proliferative state. Our work demonstrates that quiescent S. pombe cells assemble specific cytoskeleton structures that improve the swiftness of the transition back to proliferation.
Therapeutic antiviral T cells noncytopathically clear persistently infected microglia after conversion into antigen-presenting cells
Authors: Herz Jasmin , Johnson Kory R. , McGavern Dorian B.
Published: June 2015

Several viruses can infect the mammalian nervous system and induce neurological dysfunction. Adoptive immunotherapy is an approach that involves administration of antiviral T cells and has shown promise in clinical studies for the treatment of peripheral virus infections in humans such as cytomegalovirus (CMV), Epstein-Barr virus (EBV), and adenovirus, among others. In contrast, clearance of neurotropic infections is particularly challenging because the central nervous system (CNS) is relatively intolerant of immunopathological reactions. Therefore, it is essential to develop and mechanistically understand therapies that noncytopathically eradicate pathogens from the CNS. Here, we used mice persistently infected from birth with lymphocytic choriomeningitis virus (LCMV) to demonstrate that therapeutic antiviral T cells can completely purge the persistently infected brain without causing blood–brain barrier breakdown or tissue damage. Mechanistically, this is accomplished through a tailored release of chemoattractants that recruit antiviral T cells, but few pathogenic innate immune cells such as neutrophils and inflammatory monocytes. Upon arrival, T cells enlisted the support of nearly all brain-resident myeloid cells (microglia) by inducing proliferation and converting them into CD11c+ antigen-presenting cells (APCs). Two-photon imaging experiments revealed that antiviral CD8+ and CD4+ T cells interacted directly with CD11c+ microglia and induced STAT1 signaling but did not initiate programmed cell death. We propose that noncytopathic CNS viral clearance can be achieved by therapeutic antiviral T cells reliant on restricted chemoattractant production and interactions with apoptosis-resistant microglia.
Nuclear factor κB–inducing kinase activation as a mechanism of pancreatic β cell failure in obesity
Authors: Malle Elisabeth K. , Zammit Nathan W. , Walters Stacey N. , Koay Yen Chin , Wu Jianmin , Tan Bernice M. , Villanueva Jeanette E. , Brink Robert , Loudovaris Tom , Cantley James , McAlpine Shelli R. , Hesselson Daniel , Grey Shane T.
Published: June 2015

The nuclear factor κB (NF-κB) pathway is a master regulator of inflammatory processes and is implicated in insulin resistance and pancreatic β cell dysfunction in the metabolic syndrome. Whereas canonical NF-κB signaling is well studied, there is little information on the divergent noncanonical NF-κB pathway in the context of pancreatic islet dysfunction. Here, we demonstrate that pharmacological activation of the noncanonical NF-κB–inducing kinase (NIK) disrupts glucose homeostasis in zebrafish in vivo. We identify NIK as a critical negative regulator of β cell function, as pharmacological NIK activation results in impaired glucose-stimulated insulin secretion in mouse and human islets. NIK levels are elevated in pancreatic islets isolated from diet-induced obese (DIO) mice, which exhibit increased processing of noncanonical NF-κB components p100 to p52, and accumulation of RelB. TNF and receptor activator of NF-κB ligand (RANKL), two ligands associated with diabetes, induce NIK in islets. Mice with constitutive β cell–intrinsic NIK activation present impaired insulin secretion with DIO. NIK activation triggers the noncanonical NF-κB transcriptional network to induce genes identified in human type 2 diabetes genome-wide association studies linked to β cell failure. These studies reveal that NIK contributes a central mechanism for β cell failure in diet-induced obesity.
Coadjoint orbits of stepwise square integrable representations
Authors: Beltiţă Ingrid , Beltiţă Daniel
Published: June 2015

Nilpotent Lie groups with stepwise square integrable representations were recently investigated by J.A. Wolf. We give an alternative approach to these representations by relating them to the stratifications of the duals of nilpotent Lie algebras, thus proving that they correspond to a subset with relative Hausdorff topology, dense interior, and total Plancherel measure in the unitary dual of the Lie group under consideration.
A Reliable and Rapid Multiplex RT-PCR Assay for Detection of Two Potyviruses and a Pararetrovirus Infecting Canna Plants
Authors: Chauhan Ravendra P. , Wijayasekara Dulanjani , Webb Mark A. , Verchot Jeanmarie
Published: June 2015

Canna plants are subject to serious virus diseases. The three most common viruses identified in canna plants are Bean yellow mosaic virus, Canna yellow mottle virus, and Canna yellow streak virus. Recent studies indicate that canna plants are commonly infected with more than one virus. Thus, the efficient control of these viruses in canna plants requires the availability of a reliable method for detecting mixed virus infection. This report presents a two-step multiplex reverse-transcription polymerase chain reaction (RT-PCR) that was developed to simultaneously detect two potyviruses and one pararetrovirus genome. We optimized the method for nucleic acid isolation for managing a large population of samples, and the primer concentrations to ensure sensitivity and reliability of the assay, and determined the detection limit in simplex and multiplex RT-PCR assays using plasmid controls and nucleic acids isolated from virus-infected plants. Combined with an automated method for total nucleic acid isolation, this multiplex RT-PCR procedure could be routinely used for virus detection in research and diagnostic laboratories.
Geometry of mass
Authors: Dietrich D. D.
Published: June 2015

We study the effect of mass on geometric descriptions of gauge field theories. In an approach in which the massless theory resembles general relativity, the introduction of the mass entails non-zero torsion and the generalization to Einstein–Cartan–Sciama–Kibble theories. The relationships to pure torsion formulations (teleparallel gravity) and to higher gauge theories are also discussed.
The geometric semantics of algebraic quantum mechanics
Authors: Cruz Morales John Alexander , Zilber Boris
Published: June 2015

In this paper, we will present an ongoing project that aims to use model theory as a suitable mathematical setting for studying the formalism of quantum mechanics. We argue that this approach provides a geometric semantics for such a formalism by means of establishing a (non-commutative) duality between certain algebraic and geometric objects.
Twistors and amplitudes
Authors: Hodges Andrew
Published: June 2015

A brief review is given of why twistor geometry has taken a central place in the theory of scattering amplitudes for fundamental particles. The emphasis is on the twistor diagram formalism as originally proposed by Penrose, the development of which has now led to the definition by Arkani-Hamedet al.of the ‘amplituhedron’.
Protein secondary-structure description with a coarse-grained model
Authors: Kneller Gerald R. , Hinsen Konrad
Published: June 2015

A coarse-grained geometrical model for protein secondary-structure description and analysis is presented which uses only the positions of the Cαatoms. A space curve connecting these positions by piecewise polynomial interpolation is constructed and the folding of the protein backbone is described by a succession of screw motions linking the Frenet frames at consecutive Cαpositions. Using the ASTRAL subset of the SCOPe database of protein structures, thresholds are derived for the screw parameters of secondary-structure elements and demonstrate that the latter can be reliably assigned on the basis of a Cαmodel. For this purpose, a comparative study with the widely usedDSSP(Define Secondary Structure of Proteins) algorithm was performed and it was shown that the parameter distribution corresponding to the ensemble of all pure Cαstructures in the RCSB Protein Data Bank matches that of the ASTRAL database. It is expected that this approach will be useful in the development of structure-refinement techniques for low-resolution data.
Protein-complex structure completion usingIPCAS(Iterative Protein Crystal structure Automatic Solution)
Authors: Zhang Weizhe , Zhang Hongmin , Zhang Tao , Fan Haifu , Hao Quan
Published: June 2015

Protein complexes are essential components in many cellular processes. In this study, a procedure to determine the protein-complex structure from a partial molecular-replacement (MR) solution is demonstrated using a direct-method-aided dual-space iterative phasing and model-building program suite,IPCAS(Iterative Protein Crystal structure Automatic Solution). TheIPCASiteration procedure involves (i) real-space model building and refinement, (ii) direct-method-aided reciprocal-space phase refinement and (iii) phase improvement through density modification. The procedure has been tested with four protein complexes, including two previously unknown structures. It was possible to useIPCASto build the whole complex structure from one or less than one subunit once the molecular-replacement method was able to give a partial solution. In the most challenging case,IPCASwas able to extend to the full length starting from less than 30% of the complex structure, while conventional model-building procedures were unsuccessful.
Controlled crystal dehydration triggers a space-group switch and shapes the tertiary structure of cytomegalovirus immediate-early 1 (IE1) protein
Authors: Klingl Stefan , Scherer Myriam , Stamminger Thomas , Muller Yves A.
Published: June 2015

Cytomegalovirus immediate-early 1 (IE1) protein is a key viral effector protein that reprograms host cells. Controlled dehydration experiments with IE1 crystals not only extended their diffraction limit from 2.85 to 2.3 Å resolution but also triggered a monoclinic to tetragonal space-group transition with only minor alterations in the unit-cell parameters. An analysis of the pre-dehydration and post-dehydration crystal structures shows how dehydration rearranges the packing of IE1 molecules to meet the unit-cell constraints of the higher lattice symmetry. The transition fromP21toP43reduces the number of copies in the asymmetric unit from four to two, and molecules previously related by noncrystallographic symmetry merge into identical crystallographic copies in the tetragonal space group. At the same time, dehydration considerably alters the tertiary structure of one of the two remaining IE1 chains in the asymmetric unit. It appears that this conformational switch is required to compensate for a transition that is assumed to be unfavourable, namely from a highly preferred to a rarely observed space group. At the same time, the dehydration-triggered molecular reshaping could reveal an inherent molecular flexibility that possibly informs on the biological function of IE1, namely on its binding to target proteins from the host cell.
Questioning: a path to student learning experience
Authors: Ozuem Wilson , Lancaster Geoff
Published: June 2015

Purpose

– The purpose of this paper is to investigate connections between questioning, learning, achievement and conscious knowledge and beliefs held by tutors and how these are applied in a teaching/learning situation.

Design/methodology/approach

– The design of this study involved the authors listening to, but not participating in, classroom teaching sessions followed by individual in-depth discussions with tutors and students to ascertain how best to advance learning and achievement.

Findings

– Responses generated from questioning and dialogue helps tutors realign their teaching in response to the needs of learners including comprehending life issues and solving problems. Tutors should consider “think-pair share strategy” in their delivery.

Research limitations/implications

– Research was limited to one specific location, the sample was self-selected and limited to tutors who volunteered to take part in the investigation. A greater number of experimental locations with 100 per cent participation would have enhanced the validity of the findings.

Practical implications

– Learners need to be motivated to ask questions and be encouraged to become involved in discussions. Questioning and dialogue provide a framework for sharing educational objectives with students and charting their progress and this can lead to a better framework for delivery and understanding.

Social implications

– If tutors can better realign their teaching in response to the needs of learners including comprehending life issues and solving problems then this can lead to a more focused learning experience.

Originality/value

– The work was based on empirical investigations of tutors and learners in group and individual situations and the findings have been reported.
University teachers’ conceptions of “Changemaker”
Authors: Alden Rivers Bethany , Nie Ming , Armellini Alejandro
Published: June 2015

Purpose

– The purpose of this paper is to report on a study aimed at understanding the different conceptions that University of Northampton teachers hold of “Changemaker”, an institutional initiative to develop capacities for social innovation.

Design/methodology/approach

– The study took a phenomenographic approach to identify a small number of qualitatively different conceptions of Changemaker among teaching staff. Face-to-face, phenomenographic interviews were carried out with 30 teachers across the university. Transcript data were analysed using thematic inductive analysis.

Findings

– Five different conceptions of Changemaker were found: Changemaker as university strategy; Changemaker as critical thinking, perspective shifting and problem solving; Changemaker as employability; Changemaker as social betterment; and Changemaker as personal transformation.

Research limitations/implications

– The outcome space of conceptions represents the beliefs of teaching staff at the University of Northampton. The approach to research and plans for the practical application of findings may be of direct benefit to other education providers as they develop their own models for teaching and learning.

Practical implications

– The findings from this study will inform the next phase of the project, which involves the development of a skills/attributes/behaviours matrix for social innovation education.

Social implications

– An initiative, such as Changemaker, works to enhance the capacities of university students to work as agents of positive social change. By building a research programme around this initiative, the findings from this work can be disseminated and used by other higher education institutions.

Originality/value

– The findings of this study will address the absence of literature on teachers’ conceptions of phenomena related to social innovation, social entrepreneurship and intrepreneurship. Understanding teachers’ beliefs of such phenomena is relevant to the growing number of universities that address these subjects in the curriculum.
The “by right” defence in village green registration
Authors: Pratt Natalie
Published: June 2015

Purpose

– This paper aims to examine the recent jurisprudence of the Supreme Court concerning the registration of land as a town or village green (TVG). This area of law has proved contentious over the past decade and shows no sign of relenting. Most recently, in April 2014, the Supreme Court was asked to determine whether use that is pursuant to a statutory right could be qualifying use for the purposes of village green registration, which requires 20 years use “as of right”.

Design/methodology/approach

– The paper starts by summarising the law relating to the registration of land as a TVG and identifies the current problem that the courts are grappling with, namely the “by right” defence. After analysing the two leading authorities in relation to this point, the paper makes a judgment on the operation and conceptual underpinning of the “by right” defence.

Findings

– The paper concludes that the “by right” defence in the context of village green registration is a functioning concept that prevents the registration of land as a town and village green whenever the use relied upon is indulged in pursuant to a statutory right. Furthermore, the defence should also be construed with the pre-existing test for use “as of right” rather than being recognised as an additional limb to this test.

Originality/value

– The value of this paper is that it seeks to clarify an area of planning and property law that is fraught with conceptual uncertainty, and seeks to re-align the law of town and village greens with its prescriptive underpinnings.
Deciding on tax evasion – front line discretion and constraints
Authors: Boll Karen
Published: June 2015

Purpose

– The purpose of this paper is to analyse everyday reasoning in public administration. This is done by focusing on front line tax inspectors’ decisions about tax evasion.

Design/methodology/approach

– The paper presents ethnography of bureaucracy and field audits. The material stems from fieldwork conducted in the Central Customs and Tax Administration.

Findings

– The paper shows that the tax inspectors reason about tax evasion in a casuistic manner. They pay attention to similar cases and to particular circumstances of the individual cases. In deciding on tax evasion, the inspectors do not just administer the laws; they also enact a policy of fair-mindedness. Doing this they are constrained by time and man-powers, but also enabled by various organizational devices.

Research limitations/implications

– The tax inspectors that the author followed were carefully chosen and acted in accordance with procedures. The ethnography should be understood in relation to this set-up.

Originality/value

– The originality of the paper is that it shows that ethnography can open the territory of everyday reasoning in public administration. Also, it shows the discretionary room that any front line tax inspector navigates in. This is significant as revenue collection often is described as formal and dominated by a legal steering in which rules are univocal.
SEC fines alternative mutual fund adviser for improper handling of fund assets
Authors: McGrath Michael , Man Pablo J.
Published: June 2015

Purpose

– To explain that the Securities and Exchange Commission (“SEC”) brought and settled charges against an investment adviser to several alternative mutual funds alleging, among other charges, failure to comply with the custody requirements of the Investment Company Act of 1940, as amended (the “1940 Act”).

Design/methodology/approach

– To explain that the Securities and Exchange Commission (“SEC”) brought and settled charges against an investment adviser to several alternative mutual funds alleging, among other charges, failure to comply with the custody requirements of the Investment Company Act of 1940, as amended (the “1940 Act”).

Findings

– The enforcement action serves as an important reminder for the growing number of advisers of alternative mutual funds to be mindful of specific restrictions and obligations when managing registered funds that do not apply to private funds and separate accounts. This action shows that the SEC will bring charges even when the alleged violations do not result in harm to investors.

Practical implications

– The 1940 Act, the rules thereunder, and SEC staff guidance relating to alternative investment strategies are complicated and not intuitive. These standards can constrain a registered fund’s ability to employ options, futures, swaps, prime brokerage, repurchase and reverse repurchase agreements, enhanced leverage through securities lending, and other facilities. As the SEC continues to examine alternative mutual funds, advisers to these funds should remain cognizant of the obligations arising under the 1940 Act and the implementation of fund policies and procedures.

Originality/value

– Practical guidance from experienced financial services lawyers.
Integrated reporting in South Africa in 2012
Authors: Atkins Jill , Maroun Warren
Published: June 2015

Purpose

– This paper aims to explore the initial reactions of the South African institutional investment community to the first sets of integrated reports being prepared by companies listed on the Johannesburg Securities Exchange. The research highlights a shift in attitude towards ESG and integrated reporting, initial views on the first sets of integrated reports and obstacles to the preparation of high-quality reports. The study also includes recommendations for preparers.

Design/methodology/approach

– Detailed interviews are carried out with 20 experts from the South African institutional investment industry. Interpretive thematic analysis is used to identify themes and principles and construct an initial assessment of the investors’ views on South African integrated reporting.

Findings

– The new reporting framework is seen as an improvement on the traditional annual report of South African listed companies. In general, there is more emphasis on non-financial measures and evidence of an effort to integrate financial and environmental, social and governance metrics to provide a better understanding of organisational sustainability. The length of reports, repetition and a check box approach to reporting does, however, detract from the usefulness of the reports and undermine the development of an integrated thinking ethos.

Research limitations/implications

– The study is limited to exploring the views of only a single group of stakeholders at one point in time. The reader’s attention is also drawn to the fact that the study was carried out before the International Integrated Reporting Council’s framework for integrated reporting was applied by South African preparers. Nevertheless, its interpretive style allows identification of challenges to effective integrated reporting.

Originality/value

– This paper is the first to examine the views of institutional investors and analysts on South African integrated reports. It makes an important contribution to the academic literature by adding to the limited body of research on integrated reporting and corporate governance in an African setting. The study is also important for practitioners seeking to improve the quality of their integrated reports and for academics wanting to understand the problems and possible strategies for addressing these.
Government secrecy: public attitudes toward information provided by the authorities
Authors: Gunnlaugsdottir Johanna
Published: June 2015

Purpose

– The purpose of this paper is to present findings of a survey conducted during 2012 in Iceland with the intent of examining public opinion on government provision of information, i.e. whether the public felt that the authorities withheld information, either about subjects of general public interest or about public expenditures, if the authorities felt there was a reason to do so.

Design/methodology/approach

– A survey questionnaire was sent in March 2012 to almost two thousand Icelanders. This was a random sample selected from the National Registry. The response rate was almost 67 per cent. The survey was modelled on other research and resources that had examined trust toward public authorities and the influence of Freedom of Information Acts on government information practices.

Findings

– The survey discovered that the greater part of the citizenry felt that the authorities did keep important information of general public interest secret often or sometimes. Only 2-3 per cent of them believed that this never happened. Most of those surveyed felt as well that important information about public expenditures was often or sometimes withheld. Only 3-5 per cent of the respondents were of the opinion that this never happened.

Practical implications

– The results could be of value to public authorities that want to improve the provision of information and practice according to freedom of information act. They could also bring varied and valuable opportunities to the profession of records managers as well as others who practice information management.

Originality/value

– The survey adds valuable information and fulfils a need for a better understanding of what the public believes regarding government provision of information in Iceland. Although the survey is limited to Iceland, these findings may also be of value to public authorities and researchers in the Western World, Australia and New Zealand, to give a few examples where the culture and the practice of government may not be that different, as well as in other countries. The survey can lay the foundation for further research into the field.