bluuebunny/crossref_metadata_2025 huggingface dataset:
An englacial hydrologic system of brine within a cold glacier: Blood Falls, McMurdo Dry Valleys, Antarctica
Authors: BADGELEY JESSICA A. , PETTIT ERIN C. , CARR CHRISTINA G. , TULACZYK SLAWEK , MIKUCKI JILL A. , LYONS W. BERRY ,   MIDGE Science Team
Published: April 2017

Taylor Glacier hosts an active englacial hydrologic system that feeds Blood Falls, a supraglacial outflow of iron-rich subglacial brine at the terminus, despite mean annual air temperatures of −17°C and limited surface melt. Taylor Glacier is an outlet glacier of the East Antarctic ice sheet that terminates in Lake Bonney, McMurdo Dry Valleys. To image and map the brine feeding Blood Falls, we used radio echo sounding to delineate a subhorizontal zone of englacial brine upstream from Blood Falls and elongated in the ice flow direction. We estimate volumetric brine content in excess of 13% within 2 m of the central axis of this zone, and likely much higher at its center. Brine content decreases, but remains detectable, up to 45 m away along some transects. Hence, we infer a network of subparallel basal crevasses allowing injection of pressurized subglacial brine into the ice. Subglacial brine is routed towards Blood Falls by hydraulic potential gradients associated with deeply incised supraglacial valleys. The brine remains liquid within the subglacial and englacial environments through latent heat of freezing coupled with elevated salt content. Our findings suggest that cold glaciers could support freshwater hydrologic systems through localized warming by latent heat alone.
NEMATODE MANAGEMENT IN RAIN-FED SMALLHOLDER MAIZE PRODUCTION SYSTEMS UNDER CONSERVATION AGRICULTURE IN ZIMBABWE
Authors: MADAMOMBE SANDRA M. , NYAGUMBO ISAIAH , MVUMI BRIGHTON M. , NYAMUGAFATA PHILLIP , WUTA MENAS , CHINHEYA CLEOPAS C.
Published: April 2017

Nematode infestation in Sub-Saharan Africa's (SSA) cropping systems, worsened by poor crop rotations, is a major factor contributing to limited utilisation of applied nutrients and water, leading to low maize (Zea maysL.) yields particularly on sandy soils. The effects of nematode infestation on maize productivity were evaluated under conservation agriculture (CA) on granitic sandy soils in sub-humid smallholder farms of Goromonzi district of Zimbabwe. Four treatments were tested for three seasons on six smallholder farmers’ fields in a randomised complete block design, each farm being a replicate: fenamiphos 40EC (a commercial synthetic nematicide), lime + fenamiphos 40EC, lime and an untreated control. Results of the study showed that independent application of fenamiphos 40EC and lime significantly reduced plant parasitic nematode infestations in maize roots by more than 10 times those present in the untreated plots while maize yield also increased significantly. Yield increase from fenamiphos and lime applications amounted to 53 and 42% respectively, compared to the untreated controls. Maize yield was negatively correlated with density ofPratylenchusspp. nematodes. Nematode management strategies involving fenamiphos 40EC or lime could significantly reduce maize yield losses in maize-based smallholder farming systems of SSA under CA. It was more economical to use fenamiphos than lime to control nematodes.
Living with tigers Panthera tigris: patterns, correlates, and contexts of human–tiger conflict in Chitwan National Park, Nepal
Authors: Dhungana Rajendra , Savini Tommaso , Karki Jhamak Bahadur , Dhakal Maheshwar , Lamichhane Babu Ram , Bumrungsri Sara
Published: April 2017

Human–tiger conflict arises when tigers Panthera tigris attack people or their livestock, and poses a significant threat to both tigers and people. To gain a greater understanding of such conflict we examined spatio-temporal patterns, correlates, causes and contexts of conflict in Chitwan National Park, Nepal, and its buffer zone, during 2007–2014. Data, mostly from compensation applications, were collected from the Park office. Fifty-four human casualties (32 fatalities, 22 injuries) and 351 incidents of livestock depredation were recorded, clustered in defined areas, with 75.9% of human casualties occurring in the buffer zone and 66.7% within 1 km of the Park boundary. A linear model indicated there was a significant increase in human casualties during 2007–2014. Livestock were killed in proportion to their relative availability, with goats suffering the highest depredation (55%). There was a positive correlation between livestock depredation and National Park frontage (the length of Village Development Committee/municipality boundary abutting the National Park), but not human population, livestock population, forest area in the buffer zone, rainfall or temperature. There was no relationship between tiger attacks on people and any of the correlates examined. Wild prey density was not correlated with conflict. Of the tigers removed because of conflict, 73.3% were male. The majority of attacks on people occurred during accidental meetings (77.8%), mostly while people were collecting fodder or fuelwood (53.7%), and almost half (48.2%) occurred in the buffer zone forests. We recommend the use of the conflict map developed here in the prioritization of preventive measures, and that strategies to reduce conflict should include zoning enforcement, improvement of livestock husbandry, participatory tiger monitoring, an insurance scheme, and community awareness.
OVERVIEW ON THE CURRENT IMPLEMENTATION OF HEALTH TECHNOLOGY ASSESSMENT IN THE HEALTHCARE SYSTEM IN HUNGARY
Authors: Németh Bertalan , Csanádi Marcell , Kaló Zoltán
Published: April 2017

Objectives:Our objectives were to assess the current implementation of health technology assessment (HTA) in Hungary and to identify country-specific patterns of challenges and potential improvements.

Methods:We applied a structure that can be used to create HTA implementation roadmaps to evaluate various issues regarding HTA implementation. A comprehensive description of the Hungarian HTA system is presented according to relevant literature and experiences of the authors.

Results:By investigating eight components of HTA implementation, we identified the most important strengths and weaknesses of the Hungarian system. More specifically, we were mainly focusing on the emergence of HTA capacity, the establishment and current role of Department of HTA, the complex process of decision making, the quality elements developed in the near past, and the activity of Hungarian experts at international collaborations.

Conclusions:We concluded that there is a sophisticated methodological and educational basis for HTA in Hungary. A permanent focus on capacity building and changes to the reimbursement procedure can further improve transparency and the scientific basis of decision making in the country.
ATTITUDES OF ORTHOPEDIC SPECIALISTS TOWARD EFFECTS OF MEDICAL DEVICE PURCHASING
Authors: Lingg Myriam , Merida-Herrera Everth , Wyss Kaspar , Durán-Arenas Luis
Published: April 2017

Objectives: The aim of this study was to assess viewpoints of end-users concerning the purchasing process of high-risk medical devices and to discuss the relevance of health technology assessments (HTAs) at the hospital level and other potential areas for improvement of purchasing processes.

Methods: We used a cross-sectional study and assessed the attitudes and thoughts of orthopedic specialists. The study took place between June and October 2015 in Mexico.

Results: We collected data from 187 orthopedic surgeons. Involvement of orthopedic specialists in purchasing was reported by 86 percent. However, clinical practice was perceived as negatively influenced by purchasing outcomes by 92 percent. The problems were described as: material failure; effectiveness of medical devices; obsolete medical device technology; incomplete provision of implant / instrument sets; delayed provision of implants and instruments.

Conclusions: To prevent sub-standard outcomes of purchasing decisions, this study and the current literature suggest that technologies should be assessed during the purchasing process, end-users should be adequately involved, and decisions should be based on multiple criteria including clinical impact in the short-term (e.g., primary stability of implant) and long-term (e.g., survival of implant). The focus on Mexico is particularly novel and provides insights into a health system where HTA is mainly present at the macro level and can be used for the listing of medical device technologies in the standard list. This study concludes that Mexican stakeholders of the purchasing process underestimate the contribution of HTAs at the level of purchasing decisions. HTA in Mexico has improved over the past years but still requires more advancement.
Post-dispersal seed removal by rodents in Ranomafana rain forest, Madagascar
Authors: Razafindratsima Onja H.
Published: April 2017

Seed-consuming rodents are increasingly recognized for their roles in the maintenance of tree species diversity, by acting on crucial post seed-dispersal processes. Yet, studies examining the extent to which rodents may act as secondary seed dispersers and/or predators in Madagascar's forests are limited. Thread-marking seed experiments were run to address this, using the seeds of two native large-seeded, frugivore-dispersed tree species (Abrahamia thouvenotii and Cryptocarya crassifolia), in disturbed and less-disturbed habitats in the rain forests of Ranomafana National Park, during the dry season. Data show that post-dispersal handling of seeds by rodents (predation and removal) was significantly lower in disturbed than in less-disturbed habitats (1.31–3.78 times lower; n = 2200). Also, seeds were more likely to be predated or left on the forest ground after removal than being larder- or scatter-hoarded: 27–78% of the removed seeds were found on the ground, <12% found in burrows and there was no evidence of scatter-hoarding (n = 132). Based on pictures from camera traps, the native rodent species, Nesomys rufus, was potentially responsible for seed predation and/or removal in the less-disturbed habitat; but no indication of the rodent species active in the disturbed habitat was obtained. The lack of scatter-hoarding suggests a limited role of rodents in secondary seed dispersal in this system. These findings form a preliminary account of the potential roles of rodents in post seed-dispersal processes in Madagascar's forests, but this warrants further study.
Comparison of Several Nonlinear Filters for Mars Entry Navigation Using Radiometric Measurements
Authors: Xia Yuanqing , Xing Zirui , Wang Liansheng
Published: April 2017

This paper studies the application of several nonlinear filters for the problem of Mars entry navigation by using radiometric measurements from Mars orbiters and Mars Surface Beacons (MSBs). A suitable dynamic model of Mars entry is developed. The movement of MSBs due to Mars rotation is also considered in the measurement model. The performance of an Extended Kalman Filter (EKF), First-order Divided Difference Filter (DDF1), Unscented Kalman Filter (UKF), and Particle Filter (PF) is compared in terms of estimation capability and computation costs. The theoretical Cramer-Rao Lower Bound (CRLB) of estimation errors are derived for Mars entry to evaluate the performance of the filters. A consistency test is also carried out to verify the filters. In simulations, by the comparison of estimation errors, position and velocity Root Mean Square Error (RMSE), error standard deviation versus Square Root of CRLB (SR CRLB), credibility and computation time, it is concluded that DDF1 is preferred for Mars entry navigation.
‘Interests of justice’: Defining the scope of Prosecutorial discretion in Article 53(1)(c) and (2)(c) of the Rome Statute of the International Criminal Court
Authors: DE SOUZA DIAS TALITA
Published: April 2017

The International Criminal Court (ICC) was established with the aim of prosecuting individuals for the gravest crimes of concern to the international community. Yet some provisions of its Statute (the Rome Statute) recognize the need for temporarily setting aside criminal investigations or prosecutions in favour of different considerations. Two of these provisions are Article 53(1)(c) and (2)(c) of the Statute. They allow the Prosecutor of the Court to use his or her discretion in deciding not to initiate an investigation or a prosecution in the ‘interests of justice’. Nonetheless, the ambiguity of this phrase, coupled with an absent definition, have given rise to a polarized debate about its meaning and the Prosecutor's ensuing margin of discretion: some consider matters of peace and security and alternative justice mechanisms as possible ‘interests of justice’, while others exclude them. Among those adopting the latter view is the ICC's Office of the Prosecutor (OTP), as can be inferred from a 2007 Policy Paper on the Interests of Justice and a 2013 Policy Paper on Preliminary Examinations, which continue to be upheld by the Office. Against this backdrop and amid new developments at the ICC which call into question the OTP's position, the purpose of this article is to develop a comprehensive interpretation of Article 53(1)(c) and (2)(c) of the Rome Statute, using all the interpretative tools provided by Articles 31 to 33 of the Vienna Convention on the Law of Treaties.
Modelling ‘Life’ against ‘heat death’
Authors: Zak Michail
Published: April 2017

This work is inspired by the discovery of a new class of dynamical system described by ordinary differential equations coupled with their Liouville equation. These systems called self-controlled since the role of actuators is played by the probability produced by the Liouville equation. Following the Madelung equation that belongs to this class, non-Newtonian properties such as randomness, entanglement and probability interference typical for quantum systems have been described. Special attention was paid to the capability to violate the second law of thermodynamics, which makes these systems neither Newtonian, nor quantum. It has been shown that self-controlled dynamical systems can be linked to mathematical models of living systems. The discovery of isolated dynamical systems that can decrease entropy in violation of the second law of thermodynamics, and resemblances of these systems to livings suggests that ‘Life’ can slow down the ‘heat death’ of the Universe and that can be associated with the Purpose of Life.
Growing Philanthropy through Giving Circles: Collective Giving and the Logic of Charity
Authors: Eikenberry Angela M. , Breeze Beth
Published: April 2017

Whilst philanthropy has long helped fund private initiatives for public good, governments are becoming more interested in expanding this income source as pressures on public spending increase. One outcome of multiple efforts to enhance philanthropy is the growth of giving circles, which involve individual donors collaborating to support causes of mutual interest. This research examines the degree to which giving circles are a good mechanism for enhancing philanthropy. Our overarching interest is to understand if giving circles in the UK and Ireland might serve to grow philanthropy as well as shift the logic of charity to meet the expectations of policy-makers.
Salmonella typhimurium Infection Reduces Schistosoma japonicum Worm Burden in Mice
Authors: Zhu Xiaoyang , Chen Lu , Wu Junfang , Tang Huiru , Wang Yulan
Published: April 2017

Coinfection of microorganisms is a common phenomenon in humans and animals. In order to further our understanding of the progress of coinfection and the possible interaction between different pathogens, we have built a coinfection mouse model with Schistosoma japonicum and Salmonella typhimurium, and used this model to investigate the systemic metabolic and immune responses using NMR-based metabonomics and immunological techniques. Our results show that Salmonella typhimurium (ATCC14028) infection reduces the number of adult schistosomal worms and eggs, relieves symptoms of schistosomiasis and also abates the mortality of mice infected by Schistosoma japonicum. In addition, Salmonella typhimurium infection counteracts the metabolic disturbances associated with schistosomiasis, which was reflected by the reverted levels of metabolites in coinfected mice, compared with the Schistosoma japonicum infected mice. Furthermore, immune analyses also indicate that shift of the immune response to different pathogens is a result of indirect interactions between Schistosoma japonicum and Salmonella typhimurium within the host. Salmonella typhimurium infection can ameliorate Schistosoma japonicum-caused schistosomiasis in BALB/c mice, which is most likely due to inverse immune polarization. Our work provides an insight into coinfection between Schistosoma japonicum and Salmonella typhimurium, and may further contribute to the development of new tools for controlling Schistosoma japonicum-associated diseases.
A computational study of drag reduction and vortex shedding suppression of flow past a square cylinder in presence of small control cylinders
Authors: Islam Shams-Ul. , Manzoor Raheela , Islam Zia-Ul. , Kalsoom Shazia , Ying Zhou Chao
Published: April 2017

This article presents a two-dimensional numerical study of the unsteady laminar flow from a square cylinder in presence of multiple small control cylinders. The cylinders are placed in an unconfined medium at low Reynolds numbers (Re = 100 and 160). Different flow phenomena are captured for the gap spacings (g = s/D, where s is the surface-to-surface distance between the main cylinder and small control cylinders and D is the size of the main cylinder) between 0.25 – 3 and angle of attack (θ) ranging from 300 to 1800. Numerical calculations are performed by using a lattice Boltzmann method. In this paper, the important flow physics of different observed flow patterns in terms of instantaneous vorticity contours visualization, time-trace analysis of drag and lift coefficients and power spectra analysis of lift coefficient are presented and discussed. Drag reduction and suppression of vortex shedding is also discussed in detail and compared with the available experimental and numerical results qualitatively as well as quantitatively. In addition, the mean drag coefficient, Strouhal number, root-mean-square values of the drag and lift coefficients are determined and compared with a single square cylinder without small control cylinders. We found that the drag is reduced 99.8% and 97.6% for (θ, g) = (300, 3) at Re = 100 and 160, respectively.
Desorption rate of glyphosate from goethite as affected by different entering ligands: hints on the desorption mechanism
Authors: Arroyave Jeison M. , Waiman Carolina C. , Zanini Graciela P. , Tan Wenfeng , Avena Marcelo J.
Published: April 2017

Environmental contextGlyphosate is a heavily used herbicide that is mobilised in soil and sediments through adsorption–desorption processes from the surface of mineral particles. We demonstrate that the desorption rate of glyphosate from goethite, a ubiquitous mineral, is nearly independent of the concentration and nature of the substance that is used to desorb it. The results elucidate the desorption mechanism and are relevant to understand and predict the environmental mobility of glyphosate.
AbstractThe desorption kinetics of glyphosate (Gly) from goethite was studied in a flow cell using attenuated total reflectance Fourier-transform infrared spectroscopy. Because Gly forms an inner-sphere surface complex by coordinating to Fe atoms at the goethite surface, the desorption process is actually a ligand-exchange reaction, where Gly is the leaving ligand and water molecules or dissolved substances are the entering ligands. A series of possible entering ligands that can be found in nature was tested to evaluate their effect on the desorption kinetics of Gly. Contrarily to expectations, the desorption rate was quite independent of the entering ligand concentration. Moreover, the identity of this ligand (phosphate, citrate, sulfate, oxalate, EDTA, thiocyanate, humic acid, water) had only a small effect on the value of the desorption rate constant. By analogy with the reactivity of transition metal complexes in solution, it is concluded that the rate is mainly controlled by the breaking of the Fe–Gly bond, through a dissociative or a dissociative interchange mechanism. The results are relevant in understanding and predicting the environmental mobility of Gly: irrespective of the identity of the entering ligand, Gly will always desorb from iron (hydr)oxides in nature at nearly the same rate, simplifying calculations and predictions enormously. The importance of studying desorption kinetics using mineral surfaces and environmentally relevant molecules is also highlighted.
Perfect chemomechanical coupling of F
o
F
1
-ATP synthase
Authors: Soga Naoki , Kimura Kazuya , Kinosita Kazuhiko , Yoshida Masasuke , Suzuki Toshiharu
Published: April 2017

Significance

Peter D. Mitchell, a Nobel awardee in 1978, proposed that F
o
F
1
-ATP synthase converts energy between electrochemical potential of H
+
across biological membrane (

Δ

μ
∼

H
+

), which is established by respiratory chain complexes, and chemical potential of adenine nucleotide [ΔG
(ATP)
]. However, the efficiency of the energy conversion has been a matter of debate for over 50 years. In this study, with a highly reproducible analytical system using F
o
F
1
-ATP synthase from thermophilic
Bacillus
, apparently perfect energy conversion was observed. Mitchell’s prediction thus has quantitative evidence.
A 30-Minute, Monthly, Live, Webinar-Based Journal Club Activity Alters the Self-Reported Behaviors of Dermatologic Surgeons
Authors: Zavell Amy E. , Greenberg Judah N. , Alam Murad , Armbrecht Eric S. , Maher Ian A.
Published: April 2017

BACKGROUND

Journal clubs provide a way to communicate advances in recent literature. In outpatient surgical subspecialties, such as dermatologic surgery, physicians may face challenges in finding or attending meetings pertinent to their practice.

OBJECTIVE

To assess the utility of a live web-based journal club in dermatologic surgery.

MATERIALS AND METHODS

Monthly 30-minute journal club sessions covering 5 to 6 scholarly articles. Anonymous surveys were used to evaluate the utility and self-reported learning associated with each meeting.

RESULTS

From December 2012 to February 2015, 117 articles were reviewed. Survey data were acquired monthly, apart from 5 months of missing data. On average, the survey response rate was 37% (range: 7%–82%), with an average of 17 participants per monthly session (range: 9–25). The mean monthly usefulness score was 83.7 (101-point scale), with participants scoring their likelihood of returning in the future as 96.2 (0 = not likely, 100 = extremely likely). At each session, a mean of 68% of participants felt that at least one article would change their practice of medicine.

CONCLUSION

A monthly online and telephonic journal club may be a practical and effective way to inform dermatologic surgeons of new developments in high impact literature and may influence improvements in individual practice.
Computational neuroanatomy of human stratum proprium of interparietal sulcus
Authors: Uesaki Maiko , Takemura Hiromasa , Ashida Hiroshi
Published: April 2017

Recent advances in diffusion-weighted MRI (dMRI) and tractography have enabled identification of several long-range white matter tracts in the human brain. Yet, our understanding of shorter tracts, such as those within the parietal lobe, remains limited. Over a century ago, a tract connecting the superior and inferior parts of the parietal cortex was identified in a post-mortem study:Stratum proprium of interparietal sulcus(SPIS; Sachs, 1892). The tract has since been replicated in another fibre dissection study (Vergani et al. 2014), however, it has never been identified in the living human brain and its anatomical properties are yet to be described. We used dMRI and tractography to identify and characterise SPIS in vivo, and explored its spatial proximity to the cortical areas associated with optic-flow processing using fMRI. SPIS was identified bilaterally in all subjects, and its anatomical position and trajectory are consistent with previous post-mortem studies. Subsequent evaluation of the tractography results using linear fascicle evaluation and virtual lesion analysis yielded strong statistical evidence for SPIS. We also found that SPIS endpoints are adjacent to the optic-flow selective areas. In sum, we show that SPIS is a short-range tract connecting the superior and inferior parts of the parietal cortex, wrapping around the intraparietal sulcus, and that it may be a crucial anatomy underlying optic-flow processing. In vivo identification and characterisation of SPIS will facilitate further research on SPIS in relation to cortical functions, their development, and diseases that affect them.
Finger recruitment patterns during mirror movements suggest two systems for hand recovery after stroke
Authors: Ejaz Naveed , Xu Jing , Branscheidt Meret , Hertler Benjamin , Schambra Heidi , Widmer Mario , Faria Andreia V. , Harran Michelle , Cortes Juan C. , Kim Nathan , Kitago Tomoko , Celnik Pablo A. , Luft Andreas , Krakauer John W. , Diedrichsen Jörn
Published: April 2017

Accumulating behavioural and neurophysiological evidence suggests that upper-limb control relies on contributions from both cortical and subcortical motor circuits, with cortical inputs providing fine-finger function and subcortical inputs providing the ability for gross movements, respectively. During recovery of function after stroke, the relative contributions from these pathways may shift. Here we propose that mirror movements that appear after stroke provide a non-invasive assay through which relative contributions from cortical and subcortical pathways towards hand recovery can be studied. We hypothesized that mirror movements, like hand function, are generated by summed contributions from cortical and subcortical pathways, and suggest that subcortical contributions should be characterized by a broad recruitment of fingers, while cortical contributions primarily recruit the homologous finger in the passive hand. In a longitudinal stroke recovery study (Xuet al., 2016), we quantified mirror movements and paretic hand function in 53 stroke patients in the year following unilateral stroke. Mirror movements in the non-paretic hand were exaggerated early after damage (week 2), with paretic finger presses broadly recruiting multiple fingers in the non-paretic hand. On average, however, mirroring in homologous fingers was 1.76 times larger than in non-homologous fingers. Over the year, mirroring in the non-paretic hand progressively normalized with a time-course that mimicked that for the fine-finger deficits in the paretic hand. In comparison, during non-paretic finger presses, the homologous component of mirroring in the paretic hand was reduced early after stroke (week 2) but progressively normalized. Altogether, we conclude that the pattern of mirror movements across homologous and non-homologous fingers reflect the summed contributions of both cortical and subcortical systems, and we discuss the implications of our results towards hand recovery after stroke.
Distinct Regulation of History-dependent Responses by Two Cortical Interneuron Populations
Authors: Phillips Elizabeth A.K. , Schreiner Christoph E. , Hasenstaub Andrea R.
Published: April 2017

Cortical responses to repeated stimuli are highly dynamic and rapidly adaptive. Such rapid changes are prominent in all sensory cortices, across which many aspects of circuitry are conserved. As an example, in the auditory cortex, preceding sounds can powerfully suppress responses to later, spectrally similar sounds – a phenomenon called forward suppression. Whether cortical inhibitory networks shape such suppression, or whether it is wholly regulated by common mechanisms such as synaptic depression or spike-frequency adaptation, is controversial. Here, we show that optogenetically suppressing somatostatin-positive interneurons reveals facilitation in neurons that are normally forward-suppressed. This is accompanied by a weakening of forward suppression, suggesting that these interneurons regulate the strength of forward interactions. In contrast, inactivating parvalbumin-positive interneurons does not change suppression strength, but does alter its frequency-dependence. These results establish a role of cortical inhibition in forward suppression and link specific aspects of rapid sensory adaptation to genetically distinct interneuron types.
c-Maf-dependent regulatory T cells mediate immunological tolerance to intestinal microbiota
Authors: Xu Mo , Pokrovskii Maria , Ding Yi , Yi Ren , Au Christy , Galan Carolina , Bonneau Richard , Littman Dan R.
Published: April 2017

Both microbial and host genetic factors contribute to the pathogenesis of autoimmune disease1-4. Accumulating evidence suggests that microbial species that potentiate chronic inflammation, as in inflammatory bowel disease (IBD), often also colonize healthy individuals. These microbes, including theHelicobacterspecies, have the propensity to induce autoreactive T cells and are collectively referred to as pathobionts4-8. However, an understanding of how such T cells are constrained in healthy individuals is lacking. Here we report that host tolerance to a potentially pathogenic bacterium,Helicobacter hepaticus(H. hepaticus), is mediated by induction of RORγt+Foxp3+regulatory T cells (iTreg) that selectively restrain pro-inflammatory TH17 cells and whose function is dependent on the transcription factor c-Maf. WhereasH. hepaticuscolonization of wild-type mice promoted differentiation of RORγt-expressing microbe-specific iTregin the large intestine, in disease-susceptible IL-10-deficient animals there was instead expansion of colitogenic TH17 cells. Inactivation of c-Maf in the Tregcompartment likewise impaired differentiation of bacteria-specific iTreg, resulting in accumulation ofH. hepaticus-specific inflammatory TH17 cells and spontaneous colitis. In contrast, RORγt inactivation in Tregonly had a minor effect on bacterial-specific Treg-TH17 balance, and did not result in inflammation. Our results suggest that pathobiont-dependent IBD is a consequence of microbiota-reactive T cells that have escaped this c-Maf-dependent mechanism of iTreg-TH17 homeostasis.
Optimal structure of metaplasticity for adaptive learning
Authors: Khorsand Peyman , Soltani Alireza
Published: April 2017

Learning from reward feedback in a changing environment requires a high degree of adaptability, yet the precise estimation of reward information demands slow updates. We show that this tradeoff between adaptability and precision, which is present in standard reinforcement-learning models, can be substantially overcome via reward-dependent metaplasticity (reward-dependent synaptic changes that do not always alter synaptic efficacy). Metaplastic synapses achieve both adaptability and precision by forming two separate sets of meta-states: reservoirs and buffers. Synapses in reservoir meta-states do not change their efficacy upon reward feedback, whereas those in buffer meta-states can change their efficacy. Rapid changes in efficacy are limited to synapses occupying buffers, creating a bottleneck that reduces noise without significantly decreasing adaptability. In contrast, more-populated reservoirs can generate a strong signal without manifesting any observable plasticity. We suggest that ubiquitous unreliability of synaptic changes evinces metaplasticity that can provide a robust mechanism for adaptive learning.
Disabling Cas9 by an anti-CRISPR DNA mimic
Authors: Shing Jiyung , Jiang Fuguo , Liu Jun-Jie , Bray Nicholas L. , Rauch Benjamin J. , Baik Seung Hyun , Nogales Eva , Bondy-Denomy Joseph , Corn Jacob E. , Doudna Jennifer A.
Published: April 2017

CRISPR-Cas9 gene editing technology is derived from a microbial adaptive immune system, where bacteriophages are often the intended target. Natural inhibitors of CRISPR-Cas9 enable phages to evade immunity and show promise in controlling Cas9-mediated gene editing in human cells. However, the mechanism of CRISPR-Cas9 inhibition is not known and the potential applications for Cas9 inhibitor proteins in mammalian cells has not fully been established. We show here that the anti-CRISPR protein AcrIIA4 binds only to assembled Cas9-single guide RNA (sgRNA) complexes and not to Cas9 protein alone. A 3.9 Å resolution cryo-EM structure of the Cas9-sgRNA-AcrIIA4 complex revealed that the surface of AcrIIA4 is highly acidic and binds with 1:1 stoichiometry to a region of Cas9 that normally engages the DNA protospacer adjacent motif (PAM). Consistent with this binding mode, order-of-addition experiments showed that AcrIIA4 interferes with DNA recognition but has no effect on pre-formed Cas9-sgRNA-DNA complexes. Timed delivery of AcrIIA4 into human cells as either protein or expression plasmid allows on-target Cas9-mediated gene editing while reducing off-target edits. These results provide a mechanistic understanding of AcrIIA4 function and demonstrate that inhibitors can modulate the extent and outcomes of Cas9-mediated gene editing.
A mechanistic model of the spatial interaction between blue cones and blue cone bipolar cells in macaque retina
Authors: Lønborg Andreas V. , Eglen Stephen J.
Published: April 2017

The spatial positions of blue cones (BC) and blue cone bipolars (BCBP) are positively correlated in macaque retina (Kouyama & Marshak, 1997): BCs, located in the outer nuclear layer (ONL), and BCBPs, located in the inner nuclear layer (INL), tend to be located close to each other in the lateral dimension. They also form separate homotypic mosaics and, finally, most BCBPs contact only a single BC pedicle. We present a mechanistic model of the BC-BCBP interaction to account for the development of these two mosaics and their connections. It assumes that BCs are immobile and that BCBPs can migrate within the INL due to a compromise between a dendritic string force and an intrinsic INL friction force. Model parameters were selected to optimise the fit with observed fields (Kouyama & Marshak, 1997). Simulated density recovery profiles (DRPs) closely mimic the observed DRPs. In particular, for each of the five retinal fields studied, the simulated DRP for the interaction between BCs and BCBPs has a peak at distances less than around 20 μm and a small dip at distances up to the maximal lateral dendritic length (∼ 44 μm), matching the profiles of the real data. We conclude that our mechanistic model is a candidate for the unknown mechanism that drives the observed interaction between BCs and BCBPs in macaque retina.
Pooled CRISPR interference screens enable high-throughput functional genomics study and elucidate new rules for guide RNA library design inEscherichia coli
Authors: Wang Tianmin , Guo Jiahui , Guan Changge , Wu Yinan , Liu Bing , Xie Zhen , Zhang Chong , Xing Xin-Hui
Published: April 2017

Clustered regularly interspaced short palindromic repeat (CRISPR)/Cas9 technology provides potential advantages in high-throughput functional genomics analysis in prokaryotes over previously established platforms based on recombineering or transposon mutagenesis. In this work, as a proof-of-concept to adopt CRISPR/Cas9 method as a pooled functional genomics analysis platform in prokaryotes, we developed a CRISPR interference (CRISPRi) library consisting of 3,148 single guide RNAs (sgRNAs) targeting the open reading frame (ORF) of 67 genes with known knockout phenotypes and performed pooled screens under two stressed conditions (minimal and acidic medium) inEscherichia coli. Our approach confirmed most of previously described gene-phenotype associations while maintaining < 5% false positive rate, suggesting that CRISPRi screen is both sensitive and specific. Our data also supported the ability of this method to narrow down the candidate gene pool when studying operons, a unique structure in prokaryotic genome. Meanwhile, assessment of multiple loci across treatments enables us to extract several guidelines for sgRNA design for such pooled functional genomics screen. For instance, sgRNAs locating at the first 5% upstream region within ORF exhibit enhanced activity and 10 sgRNAs per gene is suggested to be enough for robust identification of gene-phenotype associations. We also optimized the hit-gene calling algorithm to identify target genes more robustly with even fewer sgRNAs. This work showed that CRISPRi could be adopted as a powerful functional genomics analysis tool in prokaryotes and provided the first guideline for the construction of sgRNA libraries in such applications.

Importance

To fully exploit the valuable resource of explosive sequenced microbial genomes, high-throughput experimental platform is needed to associate genes and phenotypes at the genome level, giving microbiologists the insight about the genetic structure and physiology of a microorganism. In this work, we adopted CRISPR interference method as a pooled high-throughput functional genomics platform in prokaryotes withEscherichia colias the model organism. Our data suggested that this method was highly sensitive and specific to map genes with previously known phenotypes, potent to act as a new strategy for high-throughput microbial genetics study with advantages over previously established methods. We also provided the first guideline for the sgRNA library design by comprehensive analysis of the screen data. The concept, gRNA library design rules and open-source scripts of this work should benefit prokaryotic genetics community to apply high-throughput mapping of defined gene set with phenotypes in a broad spectrum of microorganisms.
Evolutionary footprints reveal insights into plant microRNA biogenesis
Authors: Chorostecki Uciel , Moro Belen , Rojas Arantxa M.L. , Debernardi Juan M. , Schapire Arnaldo L. , Notredame Cedric , Palatnik Javier F.
Published: April 2017

MicroRNAs (miRNAs) are endogenous small RNAs that recognize target sequences by base complementarity. They are processed from longer precursors that harbor a fold-back structure. Plant miRNA precursors are quite variable in size and shape, and are recognized by the processing machinery in different ways. However, ancient miRNAs and their binding sites in target genes are conserved during evolution. Here, we designed a strategy to systematically analyzeMIRNAsfrom different species generating a graphical representation of the conservation of the primary sequence and secondary structure. We found that plantMIRNAshave evolutionary footprints that go beyond the small RNA sequence itself, yet, their location along the precursor depends on the specificMIRNA. We show that these conserved regions correspond to structural determinants recognized during the biogenesis of plant miRNAs. Furthermore, we found that the members of the miR166 family have unusual conservation patterns and demonstrated that the recognition of these precursors in vivo differs from other known miRNAs. Our results describe a link between the evolutionary conservation of plantMIRNAsand the mechanisms underlying the biogenesis of these small RNAs, and show that theMIRNApattern of conservation can be used to infer the mode of miRNA biogenesis.
miR-200c suppresses stemness and increases cellular sensitivity to trastuzumab in HER2+ breast cancer
Authors: Song Cailu , Wang Jin , Wang Hua , Liu Peng , Liu Longzhong , Yang Lu , Tang Hailin , Xie Xiaoming
Published: April 2017

Resistance to trastuzumab remains a major obstacle in HER2-overexpressing breast cancer treatment. miR-200c is important for many functions in cancer stem cells (CSCs), including tumor recurrence, metastasis and resistance. We hypothesized that miR-200c contributes to trastuzumab resistance and stemness maintenance in HER2-overexpressing breast cancer. In this study, we used HER2-positive SKBR3, HER2-negative MCF-7, and their CD44+CD24-phenotype mammospheres SKBR3-S and MCF-7-S to verify. Our results demonstrated that miR-200c was weakly expressed in breast cancer cell lines and cell line stem cells. Overexpression of miR-200c resulted in a significant reduction in the number of tumor spheres formed and the population of CD44+CD24-phenotype mammospheres in SKBR3-S. Combining miR-200c with trastuzumab can significantly reduce proliferation and increase apoptosis of SKBR3 and SKBR3-S. Overexpression of miR-200c also eliminated its downstream target genes. These genes were highly expressed and positively related in breast cancer patients. Overexpression of miR-200c also improved the malignant progression of SKBR3-S and SKBR3 in vivo. miR-200c plays an important role in the maintenance of the CSC-like phenotype and increases drug sensitivity to trastuzumab in HER2+ cells and stem cells.

Summary statement

miRNAs are critical in stemness maintenance and drug resistance. These data link maintenance of the stemness-related phenotype and the sensitivity of HER2+ breast cancer to miR-200c in response to trastuzumab.
Method for characterization and enhancement of 3D printing by binder jetting applied to the textures quality
Authors: Gardan Julien
Published: April 2017

Purpose

This paper aims to present a technical approach to evaluate the quality of textures obtained by an inkjet during binder jetting in 3D printing on a powder bed through contours detection to improve the quality of the surface printed according to the result of the assembly between the inkjet and a granular product.

Design/methodology/approach

The manufacturing process is based on the use of computer-aided design and a 3D printer via binder jetting. Image processing measures the edge deviation of a texture on the granular surface with the possibility of implementing a correction in an active assembly through a “design for manufacturing” (DFM) approach. Example application is presented through first tests.

Findings

This approach observes a shape alteration of the printed image on a 3D printed product, and the work used the image processing method to improve the model according to the DFM approach.

Originality/value

This paper introduces a solution for improving the texture quality on 3D printed products realized via binder jetting. The DFM approach proposes an active assembly by compensating the print errors in upstream of a product life cycle.
Restaurant and foodservice research
Authors: DiPietro Robin
Published: April 2017

Purpose

The purpose of this paper is to present a review of the foodservice and restaurant literature that has been published over the past 10 years in the top hospitality and tourism journals. This information will be used to identify the key trends and topics studied over the past decade, and help to identify the gaps that appear in the research to identify opportunities for advancing future research in the area of foodservice and restaurant management.

Design/methodology/approach

This paper takes the form of a critical review of the extant literature that has been done in the foodservice and restaurant industries. Literature from the past 10 years will be qualitatively assessed to determine trends and gaps in the research to help guide the direction for future research.

Findings

The findings show that the past 10 years have seen an increase in the number of and the quality of foodservice and restaurant management research articles. The topics have been diverse and the findings have explored the changing and evolving segments of the foodservice industry, restaurant operations, service quality in foodservice, restaurant finance, foodservice marketing, food safety and healthfulness and the increased role of technology in the industry.

Research limitations/implications

Given the number of research papers done over the past 10 years in the area of foodservice, it is possible that some research has been missed and that some specific topics within the breadth and depth of the foodservice industry could have lacked sufficient coverage in this one paper. The implications from this paper are that it can be used to inform academics and practitioners where there is room for more research, it could provide ideas for more in-depth discussion of a specific topic and it is a detailed start into assessing the research done of late.

Originality/value

This paper helps foodservice researchers in determining where past research has gone and gives future direction for meaningful research to be done in the foodservice area moving forward to inform academicians and practitioners in the industry.
Housing preferences for affordable social housing projects in Guayaquil, Ecuador
Authors: Delgado Alina , De Troyer Frank
Published: April 2017

Purpose

The purpose of this paper is to describe the principles of a conceptual model to help developers and housing users achieve their expectations regarding quality, affordability and reasonable profits. Based on the identification of housing user’s preferences extracted from the survey, data are incorporated into model simulations considering budget restrictions for developers as well as for housing users.

Design/methodology/approach

The models’ development was based on fieldwork in Guayaquil, Ecuador, using a method that includes housing users’ preferences. Developed through a “methodological pluralism”, this study identifies people-oriented variables and assumptions. Thus, a more integrated approach is proposed, crossing and covering the fields of different disciplines.

Findings

The study concludes with findings regarding the identification of the most preferred attributes of housing users and the proposal of an alternative method to incorporate quality into model simulations for estimating housing market prices. Through optimizations, it is found that the optimal number of housing units per housing types in urban projects, which translates into more reasonable profits for the developers and the provision of better and more affordable houses for the users.

Research limitations/implications

A more complete assessment of the principles described in this paper will require a larger timeframe and location of application.

Practical implications

The identification of the most preferred attributes of housing users and the inclusion in a conceptual simulation model would help private and public developers to provide better and more affordable houses for users as well as to attain reasonable profits. Further, housing national policy could also be influenced by model’s results.

Social implications

The consideration of housing user’s preferences will entail an improvement of quality of life for social housing projects.

Originality/value

The study’s main original and novel contribution is the development of an approach for the inclusion of housing preferences into model simulations by using quality points and housing demand curves.