bluuebunny/crossref_metadata_2025 huggingface dataset:
Electrically driven and electrically tunable quantum light sources
Authors: Lee J. P. , Murray E. , Bennett A. J. , Ellis D. J. P. , Dangel C. , Farrer I. , Spencer P. , Ritchie D. A. , Shields A. J.
Published: February 2017

Compact and electrically controllable on-chip sources of indistinguishable photons are desirable for the development of integrated quantum technologies. We demonstrate that two quantum dot light emitting diodes (LEDs) in close proximity on a single chip can function as a tunable, all-electric quantum light source. Light emitted by an electrically excited driving LED is used to excite quantum dots in the neighbouring diode. The wavelength of the quantum dot emission from the neighbouring driven diode is tuned via the quantum confined Stark effect. We also show that we can electrically tune the fine structure splitting.
Physics and polarization characteristics of 298 nm AlN-delta-GaN quantum well ultraviolet light-emitting diodes
Authors: Liu Cheng , Ooi Yu Kee , Islam S. M. , Verma Jai , Xing Huili (Grace) , Jena Debdeep , Zhang Jing
Published: February 2017

This work investigates the physics and polarization characteristics of 298 nm AlN-delta-GaN quantum well (QW) ultraviolet (UV) light-emitting diodes (LEDs). The physics analysis shows that the use of the AlN-delta-GaN QW structure can ensure dominant conduction band (C) to heavy-hole (HH) subband transition and significantly improve the electron and top HH subband wave function overlap. As a result, up to 30-times enhancement in the transverse-electric (TE)-polarized spontaneous emission rate of the proposed structure can be obtained as compared to a conventional AlGaN QW structure. The polarization properties of molecular beam epitaxy-grown AlN/GaN QW-like UV LEDs, which consist of 3–4 monolayer (QW-like) delta-GaN layers sandwiched by 2.5-nm AlN sub-QW layers, are investigated in this study. The polarization-dependent electroluminescence measurement results are consistent with the theoretical analysis. Specifically, the TE-polarized emission intensity is measured to be much larger than the transverse-magnetic emission, indicating significant potential for our proposed QW structure for high-efficiency TE-polarized mid-UV LEDs.
Electron and hole transport in the organic small molecule α-NPD
Authors: Rohloff R. , Kotadiya N. B. , Crăciun N. I. , Blom P. W. M. , Wetzelaer G. A. H.
Published: February 2017

Electron and hole transport properties of the organic small molecule N,N′-Di(1-naphthyl)-N,N′-diphenyl-(1,1′-biphenyl)-4,4′-diamine are investigated by space-charge-limited current measurements. The hole transport shows trap-free behavior with a mobility of 2.3 × 10−8 m2/Vs at vanishing carrier density and electric field. The electron transport, on the other hand, shows heavily trap-limited behavior, which leads to highly unbalanced transport. A trap concentration of 1.3 × 1024 m−3 was found by modeling the electron currents, similar to the universal trap concentration found in conjugated polymers. This indicates that electron trapping is a generic property of organic semiconductors, ranging from vacuum-deposited small-molecules to solution-processed conjugated polymers.
Effects of basal-plane thermal conductivity and interface thermal conductance on the hot spot temperature in graphene electronic devices
Authors: Choi David , Poudel Nirakar , Cronin Stephen B. , Shi Li
Published: February 2017

Electrostatic force microscopy and scanning thermal microscopy are employed to investigate the electric transport and localized heating around defects introduced during transfer of graphene grown by chemical vapor deposition to an oxidized Si substrate. Numerical and analytical models are developed to explain the results based on the reported basal-plane thermal conductivity, κ, and interfacial thermal conductance, G, of graphene and to investigate their effects on the peak temperature. Irrespective of the κ values, increasing G beyond 4 × 107 W m−2 K−1 can reduce the peak temperature effectively for graphene devices made on sub-10 nm thick gate dielectric, but not for the measured device made on 300-nm-thick oxide dielectric, which yields a cross-plane thermal conductance (Gox) much smaller than the typical G of graphene. In contrast, for typical G values reported for graphene, increasing κ from 300 W m−1 K−1 toward 3000 W m−1 K−1 is effective in reducing the hot spot temperature for the 300-nm-thick oxide devices but not for the sub-10 nm gate dielectric case, because the heat spreading length (l) can be appreciably increased relative to the micron-scale localized heat generation spot size (r0) only when the oxide layer is sufficiently thick. As such, enhancement of κ increases the vertical heat transfer area above the gate dielectric only for the thick oxide case. In all cases considered, the hot spot temperature is sensitive to varying G and κ only when the G/Gox ratio and r0/l ratio are below about 5, respectively.
The effect of oxygen vacancy on switching mechanism of ZnO resistive switching memory
Authors: Hu Cong , Wang Qi , Bai Shuai , Xu Min , He Deyan , Lyu Deyuan , Qi Jing
Published: February 2017

Oxygen vacancy (Vo) is believed to control the switching mechanism of metal oxide resistive switching memory. However, an accurate and quantitative theory to prove this point of view remains absent. In this letter, we propose a model combining the Poole-Frenkel effect, space charge limited current, and the modification of Vo density to simulate the current-voltage curves. The calculated results show reasonable agreements with the experimental data, which indicates that resistive switching between high resistance state and low resistance state in the devices of Al/ZnO/p+-Si is led by the density change of Vo. Furthermore, the essence of this leading effect of Vo density is explained by electrons capture and emission via oxygen vacancies. This research demonstrates the significance of Vo in theory and gives an insight into the switching mechanism.
Turning knowledge into practical benefit: a producer case-study increasing the return on investment in science
Authors: Johnson T. H.
Published: February 2017

The present paper addresses turning knowledge into practical benefit; acknowledging a critical emphasis of the career of John L. Black. Average efficiency of pasture use by beef enterprises in southern Australia is historically ~35%. Two projects established in 2002 showed that the efficiency of pasture use could approach 90% and the conservative rates observed were due to a low adoption of existing knowledge and the perceived risks from intensification. A risk-control management system, ‘More Beef from Pastures’, was developed from these projects, to identify management practices that had the largest impacts on productivity and profitability, the variables that needed to be measured and the upper and lower limits for those measurements to optimise enterprise performance. The principles from that system were incorporated into a productivity and economic spreadsheet model for a beef enterprise near Blayney on the Central Tablelands of New South Wales. The present paper reports the effects on productivity and profitability of several management scenarios, including current practice with 180 breeding cows and progeny sold in the second year after birth; buying and selling steers; making silage; or combinations of steers and silage, to maintain pasture availability between 1200 and 2600 kg DM/ha. Simulations were conducted for rainfall and growth of a phalaris–subterranean clover pasture predicted for the Blayney climate by the Sustainable Grazing Systems model for the Years 2000–2011. The simulations covered eight consecutive years from 2002 to 2009, when mean pasture growth was only 70% of the average. Results from the simulations for current practice were similar to those observed for the enterprise. The simulations showed the importance on profitability of utilising excess pasture in years of high pasture growth. The highest average profitability across years resulted from the scenario involving purchase and sale of steers, but year-to-year fluctuations were large and significant capital was required. The silage and steer-silage scenarios were intermediate in profitability, and depended on initial silage reserves and numbers of breeding cows. The exercise demonstrated that a simple spreadsheet model based on principles of animal nutrition, pasture management and economics was needed to fully evaluate alternative management strategies for practical benefit on existing beef enterprises.
Spatial distribution of organelles in leaf cells and soybean root nodules revealed by focused ion beam-scanning electron microscopy
Authors: Reagan Brandon C. , Kim Paul J. -Y. , Perry Preston D. , Dunlap John R. , Burch-Smith Tessa M.
Published: February 2017

Analysis of cellular ultrastructure has been dominated by transmission electron microscopy (TEM), so images collected by this technique have shaped our current understanding of cellular structure. More recently, three-dimensional (3D) analysis of organelle structures has typically been conducted using TEM tomography. However, TEM tomography application is limited by sample thickness. Focused ion beam-scanning electron microscopy (FIB-SEM) uses a dual beam system to perform serial sectioning and imaging of a sample. Thus FIB-SEM is an excellent alternative to TEM tomography and serial section TEM tomography. Animal tissue samples have been more intensively investigated by this technique than plant tissues. Here, we show that FIB-SEM can be used to study the 3D ultrastructure of plant tissues in samples previously prepared for TEM via commonly used fixation and embedding protocols. Reconstruction of FIB-SEM sections revealed ultra-structural details of the plant tissues examined. We observed that organelles packed tightly together in Nicotiana benthamiana Domin leaf cells may form membrane contacts. 3D models of soybean nodule cells suggest that the bacteroids in infected cells are contained within one large membrane-bound structure and not the many individual symbiosomes that TEM thin-sections suggest. We consider the implications of these organelle arrangements for intercellular signalling.
Temporal patterns of association between the jellyfish Catostylus mosaicus and a sphaeromatid isopod and parasitic anemone
Authors: Browne Joanna G. , Pitt Kylie A. , Norman Mark D.
Published: February 2017

Jellyfish form associations with a diverse fauna including parasites and commensals, yet, ecological data on these associations, particularly time series, are rare. The present study examined temporal variation in the intensities and prevalences of two symbionts, namely, a sphaeromatid isopod (Cymodoce gaimardii) and a parasitic anemone (Anemonactis clavus) of the scyphozoan jellyfish Catostylus mosaicus over a 2-year period. Jellyfish were captured from Port Phillip Bay, Victoria, Australia, approximately every 6 weeks and inspected for symbionts. The isopod occurred on C. mosaicus on 16 of the 19 sampling occasions; prevalences ranged from 5 to 85%, and were highest in summer and autumn. Intensity ranged from one to five isopods per jellyfish. Juvenile, immature and mature isopods were present. The parasitic anemone A. clavus occurred only between May and September. Prevalences were lower than for the isopod (on 5–20% of jellyfish when present) as was maximum intensity (two anemones per jellyfish). Catostylus mosaicus appears to play an important role in the life history of a suite of symbionts, and the present study is the first to examine temporal changes in the association of the jellyfish with two of these symbionts.
Physiological response and immediate mortality of gill-net-caught blacktip reef sharks (Carcharhinus melanopterus)
Authors: Dapp Derek R. , Huveneers Charlie , Walker Terence I. , Reina Richard D.
Published: February 2017

To investigate factors contributing to immediate mortality in gill-net-caught elasmobranchs, we caught and blood sampled a total of 64 sharks and rays. Blacktip reef sharks (Carcharhinus melanopterus) were the most commonly caught species and had significantly elevated plasma lactate (mean 23.3 mM) and potassium (mean 6.2 mM) concentrations following capture, suggesting physiological disturbance. The overall immediate mortality rate of C. melanopterus was 38% and mortality was significantly influenced by body size, but not location of entanglement or sex. Of the other species caught, nervous sharks (Carcharhinus cautus) were of particular concern, because this species is often caught as bycatch by gill-net fisheries throughout its range and experienced high immediate mortality rates when captured (66%; n = 12) in the present study. The results suggest that juvenile C. melanopterus are particularly susceptible to gill-net-related mortality and that fisheries management strategies for C. melanopterus bycatch should focus on reducing the likelihood of juvenile sharks encountering this gear. Given that this species is not currently considered to be threatened with extinction, population monitoring should be performed such that the suggested regulations can be implemented if populations decline to levels threatening the conservation status of the species.
Effect of tillage erosion on the distribution of CaCO3, phosphorus and the ratio of CaCO3/available phosphorus in the slope landscape
Authors: Jia L. Z. , Zhang J. H. , Wang Y. , Zhang Z. H. , Li B.
Published: February 2017

Little is known about the effect of tillage erosion on the distribution of CaCO3, phosphorus and changes in the ratio of CaCO3/available phosphorus (AP) in the hillslope landscape. The aims of the present study were to elucidate the mechanisms underlying changes in CaCO3 and AP concentrations induced by tillage erosion along slope transects and to reconstruct the historical changes in CaCO3 in soil layers at different landscape positions. Two adjacent slopes were selected from the Sichuan Basin, China, one with downslope tillage (Slope 1) and the other with upslope tillage (Slope 2) for 29 years. Then, consecutive downslope tillage by hoeing was applied five and 20 times on Slope 1. Under normal tillage (both downslope and upslope) conditions, CaCO3 concentrations increased exponentially with soil depth. However, the mixing effect of consecutive tillage (five and 20 tills) changed the vertical CaCO3 distribution patterns. For downslope tillage, the topsoil layer CaCO3 concentration was significantly lower at the toeslope than at other slope positions, but there were no significant differences between toeslope and other slope positions for upslope tillage. Consecutive tillage with five and 20 tills increased CaCO3 concentrations in the topsoil layer by 27.7% and 30.8% respectively compared with downslope tillage, but AP concentrations decreased by 26.1% and 29.0% respectively. Under normal tillage, AP concentrations decreased with increasing CaCO3 concentrations due to the adsorption and precipitation of AP by CaCO3, but this relationship disappeared after consecutive tillage. After consecutive tillage with five and 20 tills, the mean CaCO3/AP ratios of the topsoil layer were 93.5% and 88.4% greater than those for downslope tillage respectively, whereas there were no significant differences between downslope and upslope tillage. In conclusion, tillage is a process of CaCO3 replenishment and AP dilution in the surface layer of soil derived from carbonate-rich bedrocks.
An empirical machine learning method for predicting potential fire control locations for pre-fire planning and operational fire management
Authors: O'Connor Christopher D. , Calkin David E. , Thompson Matthew P.
Published: February 2017

During active fire incidents, decisions regarding where and how to safely and effectively deploy resources to meet management objectives are often made under rapidly evolving conditions, with limited time to assess management strategies or for development of backup plans if initial efforts prove unsuccessful. Under all but the most extreme fire weather conditions, topography and fuels are significant factors affecting potential fire spread and burn severity. We leverage these relationships to quantify the effects of topography, fuel characteristics, road networks and fire suppression effort on the perimeter locations of 238 large fires, and develop a predictive model of potential fire control locations spanning a range of fuel types, topographic features and natural and anthropogenic barriers to fire spread, on a 34000km2 landscape in southern Idaho and northern Nevada. The boosted logistic regression model correctly classified final fire perimeter locations on an independent dataset with 69% accuracy without consideration of weather conditions on individual fires. The resulting fire control probability surface has potential for reducing unnecessary exposure for fire responders, coordinating pre-fire planning for operational fire response, and as a network of locations to incorporate into spatial fire planning to better align fire operations with land management objectives.
The notion of gradation in meaning
Authors: Hamawand Zeki
Published: February 2017

This paper is about gradation of meaning in English, the situation in which the degree of the quality of a word increases or decreases, caused conceptually by communicative demands and expressed lexically by other words called degree adverbs. The choice of a degree adverb reflects the speaker's viewpoint and influences the listener’s reception of the message. With reference to this phenomenon, the paper explores three fundamental tenets of Cognitive Grammar. The first is that a linguistic item forms a category of interrelated senses. On this basis, degree adverbs are argued to acquire new senses relative to context of use. The second is that the meaning of a linguistic item is best understood in terms of the domain to which it belongs. On this basis, degree adverbs are argued to form sets in which they highlight different facets. The third is that the use of a linguistic item is motivated by the particular construal imposed on a scene. On this basis, the use of a degree adverb is argued to result from the particular construal the speaker chooses to describe a situation. Degree adverbs are found to be linguistic devices used to fine-tune a stance. A change in a stance requires a change in a degree adverb.
Talking about health messages
Authors: Donné Lennie , Hoeks John , Jansen Carel
Published: February 2017

Interpersonal communication has been shown to influence health campaign outcomes, but little is known about ways in which conversations can actually be elicited. In this correlational study, we tested the assumption that perceived complexity of the message can be a predictor of interpersonal communication. Forty participants were exposed to six different health messages varying in perceived complexity. The results show that the more the message was perceived as complex, the longer it took to understand it. Longer message processing times, in turn, were associated with higher intentions to talk, but only about messages that were of low personal relevance. When messages had a high personal relevance, longer processing times were associated with lower intentions to talk. Apparently, if a message is clearly relevant, longer processing due to perceived complexity is detrimental to the occurrence of interpersonal communication.
NT2 ervaringen in Amsterdam
Authors: Verbiest Fleur , ten Thije Jan D.
Published: February 2017

According to the Dutch government it is essential for migrants to learn Dutch in order to achieve social and economic independency. This article states that Dutch language proficiency is not necessary in order to survive for Spanish speaking migrants who live in Amsterdam. This statement is supported with results that are obtained through participant observation at Spanish speaking migrant organisations and 25 focus interviews with Spanish speakers. The research results lead to the conclusion that Spanish speaking migrants in Amsterdam survive by using English. The citizens of Amsterdam make it difficult for Spanish speaking migrants to learn Dutch because they prefer to speak English with them. Furthermore, also at the current labour market, Dutch is not used as an effective means of communication but instead as a selection tool. Knowledge of Dutch is only experienced as essential by Spanish speaking migrants who want to integrate and understand Dutch society.
Stressed vowel assimilation to palatal consonants in early Romance
Authors: Recasens Daniel
Published: February 2017

This study is an investigation of the phonetic causes of stressed mid and low vowel raising and diphthongization before single palatal consonants and [jC] sequences in the Early Romance languages, as for example [a] raising in Spanishlechederived from Latin [ˈlakte] ‘milk’. The initial hypothesis put to test is that the chances that vowel assimilation applies should increase with the prominence of the anticipatory consonant-to-vowel effects in tongue dorsum raising and fronting and in the second formant (F2) frequency. In accordance with this prediction, vowel assimilatory processes were found to operate most often before [j] + dentoalveolar sequences and single palatals involving maximal dorsal contact in the case of [a] (and to some extent for [ɛ ɔ] as well), and before single palatals rather than before consonant sequences with [j] in the case of [o]. Moreover, assimilation was more prone to affect [ɛ a ɔ o] than the mid high front vowel [e]. The phonetic account of vowel raising and diphthongization reported in the present study complements other explanatory proposals based on chronological and etymological factors. It also supports the notion that the categorization of segmental coarticulatory effects as assimilatory increase with coarticulation size, and that the diachronic vowel changes in question occurred at a time when palatal consonants were in the process of gaining stability.
Nowandxianzai
Authors: Boulin Myriam
Published: February 2017

The present study looks at the deictic adverbsnowand 現在 (xianzai) and examines their respective roles in English and Chinese.Nowandxianzaiare commonly considered to be semantically equivalent. Their primary value is temporal: bothnowandxianzairefer to the time of utterance, or more generally to a temporal interval which includes the time of utterance. By examining a parallel corpus of Taiwanese and English novels, this paper aims to show that apart from this present-reference value,nowandxianzaihave little in common. The analysis of aligned texts reveals that: (1)nowis more frequent thanxianzai;(2) there is an asymmetry in the temporal use of both markers. FollowingWang (2001), I argue thatnowhas a wider semantic range thanxianzai: whereasnowmight be used pragmatically (Now, why on earth did she leave at such a time?),xianzaiis limited to strict temporal reference. It appears that even in its temporal use,nowis more complex thanxianzai;nowis quasi-systematically contrastive, whereasxianzaitends to be purely deictic. We conclude thatnowis closer in function to the Chinese particlelethan to the adverbxianzai.
Compounding in German and English
Authors: Berg Thomas
Published: February 2017

German is well-known for its propensity for nominal compounding. This claim is put on a firmer empirical footing by means of a bidirectional translation study between German and English. The difference between the two languages crystallizes in the competition between compounds and phrases. Two complementary asymmetries emerge: first, German compounds are more frequently translated by English phrases than English compounds by German phrases; second, English phrases are more frequently translated by German compounds than German phrases by English compounds. An extension to other word classes shows that the compounding bias in German is not restricted to nouns. It is tentatively argued that the token frequency of word classes plays a role in the emergence of compound propensity. The heavier use of nouns and adjectives in German than in English might be partly responsible for the higher rate of nominal and adjectival compounding in the former than the latter language.
Activation of zinc phosphate coating by silver nitrate pretreatment
Authors: Abdalla Khalid , Zuhailawati Hussain
Published: February 2017

The effects of a new activation pretreatment based on silver nitrate solution on the formation and protection characteristics of zinc phosphate coating on mild steel surface were studied. The surface morphology of coated samples and microstructural evolution were analysed by the scanning electron microscopy (SEM) and the energy-dispersive spectroscopy. The protection characteristics were evaluated using potentiodynamic polarisation curves and the electrochemical impedance spectroscopy in a 3.5% NaCl solution. Experimental results revealed that the activation pretreatment with silver nitrate solution promotes the nucleation of zinc phosphate coating on steel surface which produced compact coatings with full surface coverage. Introducing the pretreatment with silver nitrate solution prior to the phosphating step strongly influences the surface morphology and corrosion resistance of the phosphate layer. The corrosion resistance of activated phosphate coatings was improved, where the corrosion potential shifted positively, and the corrosion current density was markedly reduced.
Induced accumulation of tyramine, serotonin, and related amines in response to Bipolaris sorokiniana infection in barley
Authors: Ishihara Atsushi , Kumeda Rie , Hayashi Noriko , Yagi Yukari , Sakaguchi Nanase , Kokubo Yu , Ube Naoki , Tebayashi Shin-ichi , Ueno Kotomi
Published: February 2017

The inducible metabolites were analyzed in barley leaves inoculated with Bipolaris sorokiniana, the causal agent of spot blotch of barley. HPLC analysis revealed that B. sorokiniana-infected leaves accumulated 4 hydrophilic compounds. They were purified by ODS column chromatography and preparative HPLC. Spectroscopic analyses revealed that they were tyramine (1), 3-(2-aminoethyl)-3-hydroxyindolin-2-one (2), serotonin (3), and 5,5′-dihydroxy-2,4′-bitryptamine (4). Among these, 2 and 4 have not been reported as natural products. They showed antifungal activity in an assay of inhibition of B. sorokiniana conidia germination, suggesting that they play a role in the chemical defense of barley as phytoalexins. The accumulation of 1–4 was examined also in the leaves of rice and foxtail millet. Rice leaves accumulated 2, 3, and 4, whereas foxtail millet leaves accumulated 3 and 4 in response to pathogen attack, suggesting the generality of accumulation of 3 and 4 in the Poaceae species.
Postponed Feeding Does Not Substantially Reduce Production Expense during Pond Rearing of Hybrid Catfish Fry
Authors: Mischke Charles C , Griffin Matt J , Li Menghe H , Wise David J , Greenway Terrence E
Published: February 2017

Production variables of hybrid catfish (Channel Catfish Ictalurus punctatus × Blue Catfish I. furcatus) reared in nursery ponds and then stocked were compared between fish fed immediately after stocking (standard industry practice) and fish for which feeding was postponed after stocking. Ponds (0.04 ha) were stocked with swim-up fry at 10,000 fish/pond (250,000 fish/ha). At 2 weeks poststocking, fish in the postponed feeding treatment were significantly smaller than fish in the standard feeding protocol. Therefore, all ponds began receiving commercial diets after 2 weeks. At 2 weeks poststocking and continuing through 5 weeks poststocking, the average individual fish length and weight was greater for the standard feeding protocol than for the postponed feeding protocol. At harvest, there were no differences in production variables between the two feeding protocols. Unlike a previous study with Channel Catfish fry, where feed was withheld for 6 weeks without compromising production, noticeable deficiencies in hybrid catfish fry growth were observed after only 2 weeks of feed restriction. However, compensatory growth was observed, and postponed feeding did not result in differences in production variables observed 6 weeks poststocking. At the feeding rate and feed prices during this study, we observed feed savings of only US$38.75/ha by postponing feeding for 2 weeks.
The nuclear transport receptor Importin-11 is a tumor suppressor that maintains PTEN protein
Authors: Chen Muhan , Nowak Dawid G. , Narula Navneet , Robinson Brian , Watrud Kaitlin , Ambrico Alexandra , Herzka Tali M. , Zeeman Martha E. , Minderer Matthias , Zheng Wu , Ebbesen Saya H. , Plafker Kendra S. , Stahlhut Carlos , Wang Victoria M.Y. , Wills Lorna , Nasar Abu , Castillo-Martin Mireia , Cordon-Cardo Carlos , Wilkinson John E. , Powers Scott , Sordella Raffaella , Altorki Nasser K. , Mittal Vivek , Stiles Brendon M. , Plafker Scott M. , Trotman Lloyd C.
Published: February 2017

Phosphatase and tensin homologue (PTEN) protein levels are critical for tumor suppression. However, the search for a recurrent cancer-associated gene alteration that causes PTEN degradation has remained futile. In this study, we show that Importin-11 (Ipo11) is a transport receptor for PTEN that is required to physically separate PTEN from elements of the PTEN degradation machinery. Mechanistically, we find that the E2 ubiquitin-conjugating enzyme and IPO11 cargo, UBE2E1, is a limiting factor for PTEN degradation. Using in vitro and in vivo gene-targeting methods, we show that Ipo11 loss results in degradation of Pten, lung adenocarcinoma, and neoplasia in mouse prostate with aberrantly high levels of Ube2e1 in the cytoplasm. These findings explain the correlation between loss of IPO11 and PTEN protein in human lung tumors. Furthermore, we find that IPO11 status predicts disease recurrence and progression to metastasis in patients choosing radical prostatectomy. Thus, our data introduce the IPO11 gene as a tumor-suppressor locus, which is of special importance in cancers that still retain at least one intact PTEN allele.
Importin-11 keeps PTEN safe from harm
Authors: Leslie Nick R.
Published: February 2017

In this issue, Chen et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201604025) show that Importin-11 traffics the tumor suppressor PTEN into the nucleus and in so doing protects it from cytoplasmic proteins that cause PTEN degradation. This work helps explain the nuclear accumulation of PTEN observed in many healthy tissues and, because Ipo11 mutant mice develop lung tumors, also implicates Importin-11 as a novel tumor suppressor.
The peroxisomes strike BAK: Regulation of peroxisome integrity by the Bcl-2 family
Authors: Chipuk Jerry Edward , Luna-Vargas Mark P.A.
Published: February 2017

Within the mitochondrial pathway of apoptosis, VDAC2 controls both the localization and proapoptotic activity of BAK. In this issue, Hosoi et al. (2017. J. Cell Biol. https://doi.org/10.1083/jcb.201605002) find that loss of VDAC2 diverts BAK into peroxisome membranes, revealing the ability of BAK to control peroxisome membrane integrity and the release of soluble peroxisomal matrix proteins.
Pedicled Sensate Composite Calcaneal Flap in Children With Congenital Tibial Pseudoarthrosis
Authors: Mongon Mauricio L.D. , Ribera Fernando C. , de Souza Antonio M.A. , Sposito Aurelio L. , Belangero William D. , Livani Bruno
Published: February 2017

Background:

The preservation and functionality of a limb affected by a malformation (such as congenital pseudoarthrosis of the tibia) or a severely mangled lower limb in children, despite modern reconstructive techniques, remains challenging, often eventually requiring amputation to achieve a better outcome. The classical Syme and Boyd procedures are functionally better than transtibial (TT) amputation, but are not feasible for congenital tibial pseudoarthrosis. TT amputation delivers an excellent, effective, and functional stump that usually leads, after prosthetization, to a functional gait. Unfortunately, in some situations, particularly when amputation is performed conventionally, the stump is also associated with complications. Future surgical revisions are often needed, particularly in children, because of stump overgrowth.

Methods:

Between 2008 and 2010, three patients diagnosed with congenital pseudoarthrosis of the tibia associated with neurofibromatosis who were indicated for TT amputation with calcaneal flap after failure of all previous surgical reconstructive procedures were selected. The chosen method for osteosynthesis was an external fixator of Ilizarov.

Results:

At 12 weeks of follow-up, the stump had healed in all three patients, and tibiocalcaneal fusion was achieved without complications. All patients were prosthetized and had an asymptomatic gait. After a minimum follow-up of 6 years, all three cases with the pedicled sensate composite calcaneal flap still had a strong, full weight-bearing surface and have adapted easily to the conventional prosthesis, providing a painless stump with excellent functionality.

Conclusion:

With a 0 rate of needed revisions, all 3 cases with the pedicled sensate composite calcaneal flap preserving the hind foot still have a strong, full weight-bearing surface and have easily adapted to the conventional prosthesis, providing a painless and excellent functional stump that could last a lifetime.

Level of Evidence:

Level IV.
VEPTR Implantation to Treat Children With Early-Onset Scoliosis Without Rib Abnormalities: Early Results From a Prospective Multicenter Study
Authors: El-Hawary Ron , Kadhim Muayad , Vitale Michael , Smith John , Samdani Amer , Flynn John M.
Published: February 2017

Background:

Thoracoplasty and insertion of vertical expandable prosthetic titanium rib (VEPTR) for thoracic and spine distraction has been found to be effective in the treatment of early-onset scoliosis (EOS) with ribs anomalies and congenital vertebral anomalies. The aim of this study was to evaluate the efficacy of VEPTR in preventing further progression of scoliosis without impeding spinal growth in children with progressive EOS without rib abnormalities.

Methods:

This is a prospective, multicenter, observational cohort study. Erect radiographs were analyzed for coronal and sagittal curve and height measurements at preimplant, immediate postoperative, and at 2-year follow-up.

Results:

Sixty-three patients met inclusion: 35 males and 28 females. Mean age at time of implantation was 6.1±2.4 years. Etiologies included congenital (n=6), neuromuscular (n=36), syndromic (n=4), and idiopathic (n=17). The mean follow-up was 2.2±0.4 years. Scoliosis (72±18 degrees) decreased after implant surgery (47±17 degrees) followed by slight increase at 2-year follow-up (57±18 degrees), P<0.0001. Kyphosis (48±22 degrees) also showed significant decrease after implantation (40±14 degrees), but increased after 2 years (48±16 degrees), P<0.0001. Coronal spine height measurements including T1-T12 (15.7±3 cm) and T1-S1 (25±6 cm) showed significant increases after implantation surgery (17.7±4 cm and 28.6±6 cm, respectively) and at 2 years (18.4±4 cm and 29.1±5 cm, respectively), P<0.0001. The increase in coronal spine height represented 144% of expected age-matched T1-T12 growth and 193% of expected age-matched T1-S1 growth. Similarly, sagittal spine length of T1-T12 and T1-S1 increased from 16.9±2.7 cm and 27.1±3.9 cm, respectively preoperatively to 19.7±3.5 cm and 31.9±5.1 cm, respectively at 2-year follow-up, P<0.0001. The instrumented spine segment continued growth from 25.8±5.2 cm after implantation to 27.4±5.3 cm at 2-year follow-up, P<0.0001. Thirty-one patients (49%) had at least 1 complication with total of 58 complications.

Conclusions:

At 2-year follow-up, VEPTR was effective in treating EOS without rib abnormalities with 86% of patients having an improvement in scoliosis and 94% of patients having an increased spinal height as compared with preoperative values. This study proved that spine continues to grow after VEPTR instrumentation during the distraction phase. This amount of growth represents about 40% for T1-T12 and 31% for T1-S1 spine of the expected age-matched growth based on Dimeglio reference numbers. We find this growth important as it proves continuous spine growth with VEPTR treatment.

Level of Evidence:

Level II.
IMPACT Score for Traumatic Brain Injury: Validation of the Prognostic Tool in a Spanish Cohort
Authors: Egea-Guerrero Juan José , Rodríguez-Rodríguez Ana , Gordillo-Escobar Elena , Fernández-Delgado Esperanza , Martínez-Roldán Ángela , Roldán-Reina Álvaro , Durán-Martínez Pilar , de Vega-Ríos Enrique , Freire-Aragón María Dolores , Vilches-Arenas Ángel , Murillo-Cabezas Francisco , Quintana-Díaz Manuel
Published: February 2017

Background:

The aim of this work was to validate the IMPACT (International Mission for Prognosis and Analysis of Clinical Trials in TBI) model in a Spanish cohort of patients with moderate-severe TBI (traumatic brain injury).

Setting:

Two level I neurotrauma centers.

Participants:

Patients admitted to these hospitals between 2011 and 2014 with a diagnosis of TBI and a Glasgow Coma Scale score of 12 or less.

Design:

Prospective observational study.

Main Measures:

We collected prospectively the clinical variables included in the IMPACT models. Outcome evaluation was prospectively done at 6-month follow-up according to the Glasgow Outcome Scale.

Results:

A total of 290 patients were included in the study. Forty-seven patients (16.2%) died within 6 months post-TBI, and 74 patients (25.5%) had an unfavorable outcome. The Hosmer-Lemeshow test revealed that there was no difference between observed and predicted outcomes; hence, the 3 models displayed adequate calibration for predicting 6-month mortality or unfavorable outcome. The receiver operating characteristic curve indicated that the 3 models (Core, Extended, and Lab) could accurately discriminate between favorable and unfavorable outcomes, as well as between survival and mortality (P < .001).

Conclusion:

The IMPACT model validates prediction of 6-month outcomes in a Spanish population of moderate-severe TBI. IMPACT Lab model is the one that presents a higher discriminative capacity. These results encourage the implementation of the IMPACT model as a prognostic tool in the management of patients with TBI.
Group-Based Trajectory Analysis of Emotional Symptoms Among Survivors After Severe Traumatic Brain Injury
Authors: Ren Dianxu , Fan Jun , Puccio Ava M. , Okonkwo David O. , Beers Sue R. , Conley Yvette
Published: February 2017

Objectives:

Depressive symptoms and anxiety are fairly common emotional outcomes after severe traumatic brain injury (TBI). Life satisfaction is a main factor in the general construct of subjective well-being. However, there is limited literature available on the interrelationship between emotional outcomes and life satisfaction post–severe TBI over time. The purpose of this study was to characterize distinct patterns of change in depressive symptoms, anxiety, and life satisfaction over 24 months after severe TBI and evaluate the interrelationship of different trajectory groups among them as well as associated subject characteristics.

Methods:

This prospective study used longitudinal data collected from the University of Pittsburgh Brain Trauma Research Center from survivors of severe TBI (N = 129). In addition to demographic and injury-related data, depressive symptoms, anxiety, and life satisfaction were collected at 3, 6, 12, and 24 months postinjury. A group-based trajectory model was performed to identify distinct longitudinal patterns of depressive symptoms, anxiety, and life satisfaction. The interrelationships of distinct trajectory groups were examined using χ2 tests. A multivariate logistic regression model was used to examine the predictors of different emotional symptom trajectories.

Results:

The group-based trajectory model identified 2 distinct patterns of each of 3 outcomes: constantly low and constantly high depressive symptoms group (70.4% vs 29.6%), constantly low and constantly high anxiety group (69.1% vs 30.9%), and low-decreasing and high-stable life satisfaction groups (56.3% vs 43.7%). A strong pairwise association was observed between trajectory group membership for depressive symptoms and anxiety (P < .0001), depressive symptoms and life satisfaction (P < .0001), and anxiety and life satisfaction (P < .001). Subjects with increased severe injury were more likely to belong to the high-stable depressive symptoms group, while there were no significant associations between age, gender, race, education, marriage status and distinct depressive symptoms, anxiety, and life satisfaction trajectory groups.

Conclusions:

A group-based trajectory model revealed patterns of emotional symptoms that have not been fully explored among survivors of severe TBI. There appear to be distinct trajectory patterns for depressive symptoms, anxiety, and life satisfaction, respectively. There was strong interrelationship among emotional symptoms. The findings add to our understanding of psychosocial outcomes experienced over time after severe TBI.
MACULAR DEGENERATION AND ASPIRIN USE
Authors: Small Kent W. , Garabetian Christine A. , Shaya Fadi S.
Published: February 2017

Purpose:

To review current literature of the benefits that aspirin provides for patients' cardiovascular health compared with the risk of AMD worsening.

Methods:

We performed a review and critically analyzed six cardiovascular and four ophthalmological trials regarding risks and benefits of aspirin use. The prospective randomized cardiovascular trials had a cumulative 167,580 while the 3 smaller ophthalmological data sets had a cumulative 12,015 subjects.

Results:

The reviewed meta-analysis literature demonstrated a statistically significant 32% reduction in the risk of nonfatal stroke with regular aspirin users. The study also documented that aspirin users decreased the risk of fatal vascular deaths by 15%. Of the three ophthalmological studies highlighting the adverse affects of aspirin association with AMD, all suggested an exacerbation of AMD without statistical significance and broad confidence bands.

Conclusion:

Overall, the number, size, and quality of the cardiovascular studies recommending aspirin use are far superior to the fewer, smaller and conflicting studies suggesting a possible adverse effect of aspirin use in relation to AMD. The benefits of aspirin usage include preserving the duration and quality of life by decreasing stroke and heart attack risk. These benefits seem to far outweigh the theoretical risks of possibly exacerbating wet AMD, which can be reasonably controlled with anti-VEGF therapy.
INFLUENCE OF VITRECTOMY SURGERY ON THE INTEGRITY OF OUTER RETINAL LAYERS IN DIABETIC MACULAR EDEMA
Authors: Uji Akihito , Murakami Tomoaki , Suzuma Kiyoshi , Yoshitake Shin , Arichika Shigeta , Ghashut Rima , Fujimoto Masahiro , Yoshimura Nagahisa
Published: February 2017

Purpose:

To investigate the influence of pars plana vitrectomy (PPV) on the integrity of photoreceptor layers in eyes with diabetic macular edema (DME) by using parallelism (a parameter that comprehensively reflects photoreceptor–retinal pigment epithelium [RPE] complex alterations) in spectral-domain optical coherence tomography (SD-OCT) imaging.

Methods:

A consecutive series of 64 eyes in 55 patients with diabetic macular edema who underwent pars plana vitrectomy were recruited into the study. Spectral-domain optical coherence tomography images were obtained preoperatively and 6 months after surgery. The morphologic features of the outer retinal layers were assessed quantitatively using parallelism and qualitatively by graders, including continuity of the external limiting membrane (ELM) line, continuity of the photoreceptor inner and outer segment (IS/OS) junction line, and the presence of hyperreflective foci in the outer retinal layers. The relationships between parallelism, visual acuity (VA), and photoreceptor layer status were evaluated.

Results:

After surgery, foveal thickness significantly decreased (P < 0.0001) and visual acuity improved (P < 0.0001) from baseline level. Postoperative parallelism (0.632 ± 0.137) was significantly higher than preoperative parallelism (0.531 ± 0.172) (P < 0.0001). A number of eyes with hyperreflective foci reduced after surgery, while separate evaluation of the inner and outer segment junction and external limiting membrane lines did not show significant changes. Moreover, preoperative and postoperative parallelism values showed significant correlations with postoperative visual acuity and serum lipid levels. Foveal thickness and logMAR visual acuity did not show significant correlations with any blood test data.

Conclusion:

Pars plana vitrectomy might be effective for resolution of hyperreflective foci in outer retinal layers. Parallelism is a potential marker for localization of hyperreflective foci and useful as a predictive factor for postoperative visual acuity.
FEATURES OF THE MACULA AND CENTRAL VISUAL FIELD AND FIXATION PATTERN IN PATIENTS WITH RETINITIS PIGMENTOSA
Authors: Sayman Muslubas Isil , Karacorlu Murat , Arf Serra , Hocaoglu Mumin , Ersoz Mehmet Giray
Published: February 2017

Purpose:

To evaluate macular features and fixation pattern in patients with retinitis pigmentosa (RP) compared with healthy controls, using spectral-domain optical coherence tomography and MP-1 microperimetry.

Methods:

Eighty-one eyes of 81 patients with RP and 90 eyes of 90 healthy subjects were assessed. The central foveal thickness, subfoveal choroidal thickness, ellipsoid zone length, and the mean retinal sensitivities and fixation characteristics were evaluated by spectral-domain optical coherence tomography and MP-1 microperimetry.

Results:

Compared with healthy subjects, patients with central macular thinning had lower best corrected visual acuity, central foveal thickness, ellipsoid zone length, retinal sensitivity, and visual field than patients with cystoid macular edema or no macular change (all P < 0.001). Correlations between fixation characteristics and best corrected visual acuity, central foveal thickness, ellipsoid zone length, retinal sensitivity, and visual field were statistically significant (all P < 0.001). Patients with no macular change had more centralized and stabilized fixation than patients with central foveal thinning and cystoid macular edema.

Conclusion:

The spectrum of macular features from the nearly normal retina to complete chorioretinal atrophy can be seen in RP patients without associations with age or duration of symptoms. Unlike other macular degenerations, most patients with RP obtained at least a central 2° of visual field, with foveal and stable fixation.
A Meta-Analysis on the Diagnostic Performance of Non-Echoplanar Diffusion-Weighted Imaging in Detecting Middle Ear Cholesteatoma: 10 Years On
Authors: Lingam Ravi K. , Bassett Paul
Published: February 2017

Objective:

To describe via a meta-analysis of the published literature, the performance of non-echo-planar diffusion weighted imaging (DWI) in detecting middle ear cholesteatoma.

Methodology:

A systematic review of the published literature was performed to identify original studies evaluating the diagnostic performance of non-echo-planar DWI in detecting middle ear cholesteatoma. Only studies with surgical correlation were included. A bi-variate meta-analysis and hierarchical summary receiver operating characteristic model was performed.

Results:

A total of 26 studies (1,152 patient episodes) were included. Pooled sensitivity and specificity of 0.91 (95% CI: 0.87–0.95) and 0.92 (95% CI: 0.86–0.96), respectively were obtained. Separate subgroup analysis performed for primary cholesteatoma, postoperative cholesteatoma, pediatric cases, and adult cases all showed high sensitivities (range, 0.86–0.93) and specificities (0.88–0.97). There was a statistically significant degree of heterogeneity in terms of sensitivity between all studies (I
2 value 46%) and in the pediatric subgroup (I
2 value 78%). There was no evidence of significant heterogeneity between the specificity measurements.

Conclusions:

Non-echo-planar DWI is highly sensitive and specific in detecting cholesteatoma. A large prospective multicentre randomized controlled study could validate the findings and evaluate the cost-effectiveness of DWI as an alternative for second-look surgery (control arm) in managing cases of postoperative cholesteatoma.