bluuebunny/crossref_metadata_2025 huggingface dataset:
Pediatric Hodgkin disease in Brazil: a disease with a highly heterogeneous treatment
Authors: Peres Fernanda Lagares Xavier , Chagas Antônia Pardo , Dassi Natália , Almeida Thais G. , Cagol Ângela Rech , Lorea Cecília Fernandes , Santiago Pablo , de Borba Laura Garcia , Daudt Liane Esteves , Michalowski Mariana Bohns
Published: May 2019

Standard of care and protocols for the treatment of pediatric cancer lead to a clear improvement in survival rates and quality of life. Little is known about how these treatments are implemented in Brazil. Our study aimed to evaluate children treated for Hodgkin disease (HD) in south Brazil between 2002 and 2013 through the analysis of medical records in 6 different centers.

Results

Fifty-nine children and adolescents were included. The median age was 12 years (range 3-18 years). Male:female ratio was 1.95:1. Localized disease (stage I/II) was observed in 30 patients (50.8%) while the remaining 29 (49.2%) had advanced disease (Stage III/IV).

The chemotherapeutic treatment schema was different among services and comprised three different based protocols. ABVD schema was the most frequently used (52 children (88.1%)). The number of cycles was highly variable (4-16 cycles) even at the same clinical stage and with similar clinical response.

Conclusion

These data highlight the importance of turning the “best practice policies” readily available to all pediatric oncologists. Local protocols allow integrative studies among centers that would certainly maintain or improve cure rates, reduce long-term toxicity and evaluate specific biological characteristics of these diseases in our population. For these reasons, we reinforce the idea that standardization of treatment in pediatric oncology is a child health priority and also a viable low-cost strategy to improve care in middle-income countries such as Brazil.
Medicago truncatulaFerroportin2 mediates iron import into nodule symbiosomes
Authors: Escudero Viviana , Abreu Isidro , Tejada-Jiménez Manuel , Rosa-Núñez Elena , Quintana Julia , Isabel Prieto Rosa , Larue Camille , Wen Jianqi , Villanova Julie , Mysore Kirankumar S. , Argüello José M. , Castillo-Michel Hiram , Imperial Juan , González-Guerrero Manuel
Published: May 2019

Iron is an essential cofactor for symbiotic nitrogen fixation. It is required by many of the enzymes facilitating the conversion of N2into NH4+by endosymbiotic bacteria living within root nodule cells, including signal transduction proteins, O2homeostasis systems, and nitrogenase itself. Consequently, host plants have developed a transport network to deliver essential iron to nitrogen-fixing nodule cells. Model legumeMedicago truncatula Ferroportin2(MtFPN2) is a nodule-specific gene that encodes an iron-efflux protein. MtFPN2 is located in intracellular membranes in the nodule vasculature, and in the symbiosome membranes that contain the nitrogen-fixing bacteria in the differentiation and early-fixation zones of the nodules. Loss-of-function ofMtFPN2leads to altered iron distribution and speciation in nodules, which causes a reduction in nitrogenase activity and in biomass production. Using promoters with different tissular activity to driveMtFPN2expression inMtFPN2mutants, we determined that MtFPN2-facilitated iron delivery across symbiosomes is essential for symbiotic nitrogen fixation, while its presence in the vasculature does not seem to play a major role in in the conditions tested.
TRITEX: chromosome-scale sequence assembly of Triticeae genomes with open-source tools
Authors: Monat Cécile , Padmarasu Sudharsan , Lux Thomas , Wicker Thomas , Gundlach Heidrun , Himmelbach Axel , Ens Jennifer , Li Chengdao , Muehlbauer Gary J. , Schulman Alan H. , Waugh Robbie , Braumann Ilka , Pozniak Curtis , Scholz Uwe , Mayer Klaus F. X. , Spannagl Manuel , Stein Nils , Mascher Martin
Published: May 2019

Chromosome-scale genome sequence assemblies underpin pan-genomic studies. Recent genome assembly efforts in the large-genome Triticeae crops wheat and barley have relied on the commercial closed-source assembly algorithm DeNovoMagic. We have developed TRITEX, an open-source computational workflow that combines paired-end, mate-pair, 10X Genomics linked-read with chromosome conformation capture sequencing data to construct sequence scaffolds with megabase-scale contiguity ordered into chromosomal pseudomolecules. We evaluated the performance of TRITEX on publicly available sequence data of tetraploid wild emmer and hexaploid bread wheat, and constructed an improved annotated reference genome sequence assembly of the barley cultivar Morex as a community resource.
Shake-it-off: A simple ultrasonic cryo-EM specimen preparation device
Authors: Rubinstein John L. , Guo Hui , Ripstein Zev A. , Haydaroglu Ali , Au Aaron , Yip Christopher M. , Di Trani Justin M. , Benlekbir Samir , Kwok Timothy
Published: May 2019

Although microscopes and image analysis software for electron cryomicroscopy (cryo-EM) have improved dramatically in recent years, specimen preparation methods have lagged behind. Most strategies still rely on blotting microscope grids with paper to produce a thin film of solution suitable for vitrification. This approach loses more than 99.9% of the applied sample and requires several seconds, leading to problematic air-water interface interactions for macromolecules in the resulting thin film of solution and complicating time-resolved studies. Recently developed self-wicking EM grids allow use of small volumes of sample, with nanowires on the grid bars removing excess solution to produce a thin film within tens of milliseconds from sample application to freezing. Here we present a simple cryo-EM specimen preparation device that uses components from an ultrasonic humidifier to transfer protein solution onto a self-wicking EM grid. The device is controlled by a Raspberry Pi single board computer and all components are either widely available or can be manufactured by online services, allowing the device to be constructed in laboratories that specialize in cryo-EM, rather than instrument design. The simple open-source design permits straightforward customization of the instrument for specialized experiments.

Synopsis

A method is presented for high-speed low-volume cryo-EM specimen preparation with a device constructed from readily available components.
Control of density and composition in an engineered two-member bacterial community
Authors: McCardell Reed D. , Pandey Ayush , Murray Richard M.
Published: May 2019

As studies continue to demonstrate how our health is related to the status of our various commensal microbiomes, synthetic biologists are developing tools and approaches to control these microbiomes and stabilize healthy states or remediate unhealthy ones. Building on previous work to control bacterial communities, we have constructed a synthetic two-member bacterial consortium engineered to reach population density and composition steady states set by inducer inputs. We detail a screening strategy to search functional parameter space in this high-complexity genetic circuit as well as initial testing of a functional two-member circuit.

We demonstrate non-independent changes in total population density and composition steady states with a limited set of varying inducer concentrations. After a dilution to perturb the system from its steady state, density and composition steady states are not regained. Modeling and simulation suggest a need for increased degradation of intercellular signals to improve circuit performance. Future experiments will implement increased signal degradation and investigate the robustness of control of each characteristic to perturbations from steady states.
Microbiome composition shapes rapid genomic adaptation ofDrosophila melanogaster
Authors: Rudman Seth M. , Greenblum Sharon , Hughes Rachel C. , Rajpurohit Subhash , Kiratli Ozan , Lowder Dallin B. , Lemmon Skyler G. , Petrov Dmitri A. , Chaston John M. , Schmidt Paul
Published: May 2019

Population genomic data has revealed patterns of genetic variation associated with adaptation in many taxa. Yet understanding the adaptive process that drives such patterns is challenging - it requires disentangling the ecological agents of selection, determining the relevant timescales over which evolution occurs, and elucidating the genetic architecture of adaptation. Doing so for the adaptation of hosts to their microbiome is of particular interest with growing recognition of the importance and complexity of host-microbe interactions. Here, we track the pace and genomic architecture of adaptation to an experimental microbiome manipulation in replicate populations ofDrosophila melanogasterin field mesocosms. Manipulation of the microbiome altered population dynamics and increased divergence between treatments in allele frequencies genome-wide, with regions showing strong divergence found on all chromosomes. Moreover, at divergent loci previously associated with adaptation across natural populations, we found that the more common allele in fly populations experimentally enriched for a certain microbial group was also more common in natural populations with high relative abundance of that microbial group. These results suggest that microbiomes may be an agent of selection that shapes the pattern and process of adaptation and, more broadly, that variation in a single ecological factor within a complex environment can drive rapid, polygenic adaptation over short timescales.

Significance statement

Natural selection can drive evolution over short timescales. However, there is little understanding of which ecological factors are capable of driving rapid evolution and how this rapid evolution alters allele frequencies across the genome. Here we combine a field experiment with population genomic data from natural populations across a latitudinal gradient to assess whether and how microbiome composition drives rapid genomic evolution of host populations. We find that differences in microbiome composition cause divergence in allele frequencies genome-wide, including in genes previously associated with local adaptation. Moreover, we observed concordance between experimental and natural populations in terms of the direction of allele frequency change, suggesting that microbiome composition may be an agent of selection that drives adaptation in the wild.
Nuclear Expression and DNA Binding Capacity of Receptor for Advanced Glycation End Products in Renal Tissue
Authors: Harcourt Brooke E. , McClelland Aaron D. , Yamamoto Hiroshi , Yonekura Hideto , Yamamoto Yasuhiko , Penfold Sally A , Fotheringham Amelia K. , Vesey David A. , Johnson David W. , Coughlan Melinda T. , Cooper Mark E. , Kantharidis Phillip , Forbes Josephine M.
Published: May 2019

TheAGERgene encodes for a number of RAGE isoforms, with the membrane bound signal transduction and “decoy” circulating soluble RAGE being the best characterised. Here we demonstrate a novel nuclear isoform of RAGE in mice and human kidney cortex which by cell and size fractionation we determined to be approximately 37kda. This nuclear RAGE isoform is functional and binds to DNA sequences within the upstream 5’ promoter region of its own gene,AGER. This binding was shown to be abrogated by mutating the DNA consensus binding sequences during electromobility shift assay (EMSA) and was independent of NF-□B or AP-1 binding. Cotransfection of expression constructs encoding various RAGE isoforms along withAGERgene promoter reporter-plasmids identified that the most likely source of the nuclear isoform of RAGE was a cleavage product of the nt-RAGE isoform. In obese mice with impaired kidney function, there was increased binding of nuclear RAGE within the A. Region ofagergene promoter with corresponding increases in membrane bound RAGE in renal cells. These findings were reproducedin vitrousing proximal tubule cells. Hence, we postulate that RAGE expression is in part, self-regulated by the binding of a nuclear RAGE isoform to the promoter of theAGERgene (encoding RAGE) in the kidney. We also suggest that this RAGE self-regulation is altered under pathological conditions and this may have implications for chronic kidney disease.
Quantitative analysis and medium components optimizing for culturing a fastidious bacterium Christensenella minuta
Authors: Xiao Hongshi , Liu Binghuan , Yong Jie , Zhou Haiyan
Published: May 2019

Christensenella minuta is a heritable bacterium with controversial physiologies associating with both obesity and potential pathogenicity. Since this bacterium is fastidious to culture, it is hardly to well understand its biological feature. We develop a strategy for statistical analysis of this low abundant strain and optimize culture condition to make a significant improvement on its biomass and facilitate the researches about the metabolism and function of this bacterium. Basing on the fluorogenic quantitative technology, a quantitative approach was successfully constructed for Christensenella minuta by plotting Ct value from fluorescence quantitative PCR against the logarithm of concentration gradient of plasmids containing 16S rDNA of the strain. This method exhibited to have specificity on analyzing the strain biomass statistically. For improving the strain biomass, “komodo” predicted to optimize medium components and metabonomics analysis explored the catabolites addition effects on culture improvement. With the aid of Plackett-Burman and Box-Behnken in Design-Expert 8.0.6, the PB and response surface experiment were designed and analyzed from the single factor results. On the modified GAM medium, the strain concentration was found increasing markedly by 10 times. The addition of some amino acids, vitamins and inorganic salts has contributions for the strain multiplication, especially L-cysteine, VB6 and NaCl. The addition of 55 mg/L of L-cysteine, 20.5 mg/L VB6 and 55 g/L NaCl into the modified GAM medium increased the biomass by 3.59 times compared to the biomass on only modified GAM medium according to the response surface experiment. Through the newly constructed method, we successfully analyzed the amount of Christensenella minuta and obtained a novel medium to increase biomass significantly.

Importance

Christensenella minuta is a heritable bacterium with controversial physiologies associating with both obesity and potential pathogenicity. Since this bacterium is fastidious to culture, it is hard to well understand its biological feature. We develop a strategy for statistical analysis of this low abundant strain and optimize culture condition to make a significant improvement on its biomass and facilitate the researches about the metabolism and function of this bacterium. This work combined the prediction tools and experiments to improve the medium components of C. munita and successfully enhance the culturing and increase biomass by more than 10-fold. From this perspective, the project throws some new ideas and also enables access to new knowledge and information in uncultured microbial resources.
Boosting with ALVAC-HIV and AIDSVAX B/E enhances Env constant region 1 and 2 antibody-dependent cellular cytotoxicity
Authors: Easterhoff David , Pollara Justin , Luo Kan , Tolbert William D. , Young Brianna , Mielke Dieter , Jha Shalini , O’Connell Robert J. , Vasan Sandhya , Kim Jerome , Michael Nelson L. , Excler Jean-Louis , Robb Merlin L. , Rerks-Ngarm Supachai , Kaewkungwal Jaranit , Pitisuttithum Punnee , Nitayaphan Sorachai , Sinangil Faruk , Tartaglia James , Phogat Sanjay , Kepler Thomas B. , Alam S. Munir , Wiehe Kevin , Saunders Kevin O. , Montefiori David C. , Tomaras Georgia D. , Moody M. Anthony , Pazgier Marzena , Haynes Barton F. , Ferrari Guido
Published: May 2019

Induction of protective antibodies is a critical goal of HIV-1 vaccine development. One strategy is to induce non-neutralizing antibodies that kill virus-infected cells as these antibody specificities have been implicated in slowing HIV-1 disease progression and in protection. HIV-1 Env constant region 1 and 2 (C1C2) antibodies frequently contain potent antibody dependent cellular cytotoxicity (ADCC) making them a vaccine target. Here we explore the effect of delayed and repetitive boosting of RV144 vaccinee recipients with ALVAC/AIDSVAX B/E on the C1C2-specific antibody repertoire. It was found that boosting increased clonal lineage specific ADCC breadth and potency. A ligand crystal structure of a vaccine-induced broad and potent ADCC-mediating C1C2-specific antibody showed that it bound a highly conserved Env gp120 epitope. Thus, rationally designed boosting strategies to affinity mature these type of IgG C1C2-specific antibody responses may be one method by which to make an improved HIV vaccine with higher efficacy than seen in the RV144 trial.

Significance

Over one million people become infected with HIV-1 each year making the development of an efficacious HIV-1 vaccine an important unmet medical need. The RV144 human HIV-1 vaccine-regimen is the only HIV-1 clinical trial to date to demonstrate vaccine-efficacy. An area of focus has been on identifying ways by which to improve upon RV144 vaccine-efficacy. The RV305 HIV-1 vaccine-regimen was a follow-up boost of RV144 vaccine-recipients that occurred 6-8 years after the conclusion of RV144. Our studies focused on the effect of delayed boosting in humans on the vaccine-induced antibody repertoire. It was found that boosting with a HIV-1 Env vaccine increased antibody-mediated effector function potency and breadth.
Invasion and extinction dynamics of mating types under facultative sexual reproduction
Authors: Czuppon Peter , Constable George W. A.
Published: May 2019

In sexually reproducing isogamous species, syngamy between gametes is generally not indiscriminate, but rather restricted to occurring between complementary self-incompatible mating types. A longstanding question regards the evolutionary pressures that control the number of mating types observed in natural populations, which ranges from two to many thousands. Here, we describe a population genetic null model of this reproductive system and derive expressions for the stationary probability distribution of the number of mating types, the establishment probability of a newly arising mating type and the mean time to extinction of a resident type. Our results yield that the average rate of sexual reproduction in a population correlates positively with the expected number of mating types observed. We further show that the low number of mating types predicted in the rare-sex regime is primarily driven by low invasion probabilities of new mating type alleles, with established resident alleles being very stable over long evolutionary periods. Moreover, our model naturally exhibits varying selection strength dependent on the number of present mating types. This results in higher extinction and lower invasion rates for an increasing number of residents.
The dynamics of stem and crown groups
Authors: Budd Graham E. , Mann Richard P.
Published: May 2019

The fossil record of the origins of major groups is of great interests to many biologists, especially when the fossil record apparently conflicts with timings based on molecular clock estimates. Here we model the diversity of “stem” (basal) and “crown” (modern) members of groups as seen in the fossil record, using a “birth-death model”. Under background conditions, the stem group members must diversify rapidly until the modern crown group emerges, at which point their diversity rapidly collapses, followed shortly by their extinction. Mass extinctions can disturb this pattern to create very diverse stem groups such as the dinosaurs and trilobites. Understanding these null-hypothesis patterns is essential for framing ecological and evolutionary explanations for how major groups originate and subsequently evolve.
Genomic basis of circannual rhythm in the european corn borer moth
Authors: Kozak Genevieve M. , Wadsworth Crista B. , Kahne Shoshanna C. , Bogdanowicz Steven M. , Harrison Richard G. , Coates Brad S. , Dopman Erik B.
Published: May 2019

Genetic variation in life-history timing allows populations to synchronize with seasonal cycles but little is known about the molecular mechanisms that produce differences in circannual rhythm in nature. Changes in diapause timing in the European corn borer moth (Ostrinia nubilalis) have facilitated rapid response to shifts in winter length encountered during range expansion and from climate change, with some populations emerging from diapause earlier to produce an additional generation per year. We identify genomic variation associated with changes in the time spent in winter diapause and show evidence that the circadian clock genes period (per) and pigment dispersing factor receptor (Pdfr) interact to underlie this adaptive polymorphism in circannual rhythm. Per and Pdfr are located within two epistatic QTL, strongly differ in allele frequency among individuals that pupate earlier or later, have the highest linkage disequilibrium among gene pairs in the QTL regions despite separation by > 4 megabases, and possess amino-acid changes likely to affect function. One per mutation in linkage disequilibrium with Pdfr creates a novel putative clock-cycle binding site found exclusively in populations that pupate later. We find associated changes in free-running daily circadian rhythm, with longer daily rhythms in individuals that end diapause early. These results support a modular connection between circadian and circannual timers and provide testable hypotheses about the physiological role of the circadian clock in seasonal synchrony. Winter length is expected to continually shorten from climate warming and we predict these gene candidates will be targets of selection for future adaptation and population persistence.
Histone Tail Dynamics in Partially Disassembled Nucleosomes During Chromatin Remodeling
Authors: Kameda T. , Awazu A. , Togashi Y.
Published: May 2019

Nucleosomes are structural units of the chromosome consisting of DNA wrapped around histone proteins, and play important roles in compaction and regulation of the chromatin structure. While the structure and dynamics of canonical nucleosomes have been studied extensively, those of nucleosomes in intermediate states, that occur when their structure or positioning is modulated, have been less understood. In particular, the dynamic features of partially disassembled nucleosomes have not been discussed in previous studies. Using all-atom molecular dynamics simulations, in this study, we investigated the dynamics and stability of nucleosome structures lacking a histone-dimer. DNA in nucleosomes lacking a histone H2A/H2B dimer was drastically deformed due to loss of local interactions between DNA and histones. In contrast, conformation of DNA in nucleosomes lacking H3/H4 was similar to the canonical nucleosome, as the H2A C-terminal domain infiltrated the space originally occupied by the dissociated H3/H4 histones and stabilized DNA in close proximity. Our results suggest that, besides histone chaperones, the intrinsic dynamics of nucleosomes support the exchange of H2A/H2B, which is significantly more frequent than that of H3/H4.

Statement of Significance

Eukaryotic chromosomes are composed of nucleosomes, in which the DNA wraps around the core histone proteins. To enable transcription and replication of DNA, or to modulate these functions by exchange of histones, nucleosomes should be at least partially disassembled, as evidenced by the observation of nucleosome structures lacking an H2A/H2B histone dimer by crystallography. The dynamic behavior of nucleosomes in such intermediate states may affect gene expression and repair, however it has not been completely elucidated so far. In this study, we adopted molecular dynamics simulations to analyze the conformational changes in partially disassembled nucleosomes. Enhanced structural fluctuations of DNA were observed in these nucleosomes, which may, as well as specific histone chaperones, support the exchange of H2A/H2B.
Early origin and deep conservation of enhancers in animals
Authors: Wong Emily S , Tan Siew Zhuan , Garside Victoria , Vanwalleghem Gilles , Gaiti Federico , Scott Ethan , McGlinn Edwina , Francois Mathias , Degnan Bernard M
Published: May 2019

Transcription factors (TFs) bind DNA enhancer sequences to regulate gene transcription in animals. Unlike TFs, the evolution of enhancers has been difficult to trace because of their rapid evolution. Here, we show enhancers from the sponge Amphimedon queenslandica can drive cell type-specific reporter gene expression in zebrafish and mouse, despite sponge and vertebrate lineages diverging over 700 million years ago. Although sponge enhancers, which are present in both highly conserved syntenic gene regions (Islet–Scaper, Ccne1–Uri and Tdrd3–Diaph3) and sponge-specific intergenic regions, have no significant sequence identity with vertebrate genomic sequences, the type and frequency of TF binding motifs in the sponge enhancer allow for the identification of homologous enhancers in bilaterians. Islet enhancers identified in human and mouse Scaper genes drive zebrafish reporter expression patterns that are almost identical to the sponge Islet enhancer. The existence of homologous enhancers in these disparate metazoans suggests animal development is controlled by TF-enhancer DNA interactions that were present in the first multicellular animals.

One-sentence summary

Enhancer activity is conserved across 700 million years of trans-phyletic divergence.
Rapid identification of homozygosity and site of wild relative introgressions in wheat through chromosome-specific KASP genotyping assays
Authors: Grewal Surbhi , Hubbart-Edwards Stella , Yang Caiyun , Devi Urmila , Baker Lauren , Heath Jack , Ashling Stephen , Scholefield Duncan , Howells Caroline , Yarde Jermaine , Isaac Peter , King Ian P. , King Julie
Published: May 2019

For future food security it is important that wheat, one of the most widely consumed crops in the world, can survive the threat of abiotic and biotic stresses. New genetic variation is currently being introduced into wheat through introgressions from its wild relatives. For trait discovery, it is necessary that each introgression is homozygous and hence stable. Breeding programs rely on efficient genotyping platforms for marker-assisted selection (MAS). Recently, single nucleotide polymorphism (SNP) based markers have been made available on high-throughput Axiom® SNP genotyping arrays. However, these arrays are inflexible in their design and sample numbers, making their use unsuitable for long-term MAS. SNPs can potentially be converted into Kompetitive allele-specific PCR (KASP™) assays which are comparatively cost-effective and efficient for low-density genotyping of introgression lines. However, due to the polyploid nature of wheat, KASP assays for homoeologous SNPs can have difficulty in distinguishing between heterozygous and homozygous hybrid lines in a backcross population. To identify co-dominant SNPs, that can differentiate between heterozygotes and homozygotes, we PCR-amplified and sequenced genomic DNA from potential single-copy regions of the wheat genome and compared them to orthologous copies from different wild relatives. A panel of 620 chromosome-specific KASP assays have been developed that allow rapid detection of wild relative segments and provide information on their homozygosity and site of introgression in the wheat genome. A set of 90 chromosome-nonspecific assays was also produced that can be used for genotyping introgression lines. These multipurpose KASP assays represent a powerful tool for wheat breeders worldwide.
A First-Order Design Requirement to Prevent Edema in Mechanical Counter-Pressure Space Suit Garments
Authors: Carr Christopher E. , Treviño Loretta
Published: May 2019

Introduction

Mechanical counter-pressure (MCP) space suits may provide enhanced mobility relative to gas-pressure space suits. One challenge to realizing operational MCP suits is the potential for edema caused by spatial variations in the applied body-surface pressure (dP). We determined a first-order requirement for these variations.

Methods

Darcy’s law relates volume flux, of fluid from capillaries to the interstitial space, to transmural hydraulic and osmotic pressure differences. Albumin and fibrinogen levels determine, to first order, the capillary oncotic pressure (COP). We estimated dP, neglecting hydrostatic pressure differences, by equating the volume flux under MCP and under normal with the volume flux under abnormal variations in COP; then we compared these estimates to results from MCP garment studies.

Results

Normal COP varies from 20-32 mm Hg; with constant hydraulic conductivity, dP≈12 mm Hg. In nephrotic syndrome, COP may drop to 11 mm Hg, yielding dP≈15 mm Hg relative to mid-normal COP. Previous studies found dPmax =151 mm Hg (MCP glove; finger and hand dorsum relative to palm), dPmax=51 mm Hg (MCP arm; finger, hand dorsum, and wrist relative to arm), and dP=52, 90 and 239 mm Hg (three MCP lower leg garments).

Conclusions

MCP garments with dPmax≤12 mm Hg are unlikely to produce edema or restrict capillary blood flow; however, garments with dPmax>12 mm Hg will not necessarily produce edema. For example, the hydrostatic pressure gradient at the feet in 1g can range from 70-90 mm Hg. Current garment prototypes do not meet our conservative design requirement.
An asexual flower ofSilene latifoliaandMicrobotryum lychnidis-dioicaepromoting its sexual-organ development
Authors: Kawamoto Hiroki , Yamanaka Kaori , koizumi Ayako , Ishii Kotaro , Kazama Yusuke , Abe Tomoko , Kawano Shigeyuki
Published: May 2019

Silene latifoliais a dioecious flowering plant with sex chromosomes in the family Caryophyllaceae. Development of a gynoecium and stamens are suppressed in the male and female flowers ofS. latifolia, respectively.Microbtryum lychnidis-dioicaepromotes stamen development when it infects the female flower. If suppression of the stamen and gynoecium development is regulated by the same mechanism, suppression of gynoecium and stamen development is released simultaneously with the infection byM. lychnidis-dioicae. To assess this hypothesis, an asexual mutant, without gynoecium or stamen, was infected withM. lychnidis-dioicae. A filament of the stamen in the infected asexual mutant was elongated at stages 11 and 12 of the flower bud development as well as the male, but the gynoecium did not form. Instead of the gynoecium, a filamentous structure was suppressed as in the male flower. Developmental suppression of the stamen was released byM. lychnidis-dioicae, but that of gynoecium development was not released. It is thought, therefore, that the suppression of gynoecium development was not released by the infection ofM. lychnidis-dioicae. M. lychnidis-dioicaewould have a function similar to SPF since the elongation of the stamen that is not observed in the healthy asexual mutant was observed after stage 8 of flower bud development. Such an infection experiment also that the Y chromosome of the asexual mutant has genes related to the differentiation of archesporial cells, but none related to maturation of the tapetal cells.
Crystal structure of the SPRY domain of human SPSB2 in the apo state
Authors: Luo Yanhong , Li Kefa , Yang Jinjin , Zhang Danting , Zhou Yuying , Kuang Zhihe
Published: May 2019

The SPRY domain-containing SOCS box protein 2 (SPSB2) is one of four mammalian SPSB proteins that are characterized by a C-terminal SOCS box and a central SPRY/B30.2 domain. SPSB2 interacts with inducible nitric oxide synthase (iNOS) via the SPRY domain and polyubiquitinates iNOS, resulting in its proteasomal degradation. Inhibitors that can disrupt SPSB2–iNOS interaction and augment NO production may serve as novel anti-infective and anticancer agents. The previously determined murine SPSB2 structure may not reflect the true apo conformation of the iNOS-binding site. Here, the crystal structure of human SPSB2 SPRY domain in the apo state is reported at a resolution of 1.9 Å. Comparison of the apo and ligand-bound structures reveals that the iNOS-binding site is highly preformed and that major conformational changes do not occur upon ligand binding. Moreover, the C-terminal His6tag of the recombinant protein binds to a shallow pocket adjacent to the iNOS-binding site on a crystallographically related SPSB2 molecule. These findings may help in structure-based and fragment-based SPSB2 inhibitor design in the future.
The crystal structures of the ligand N-(quinolin-8-yl)pyrazine-2-carboxamide and of a tetranuclear copper(II) complex
Authors: Cati Dilovan S. , Stoeckli-Evans Helen
Published: May 2019

The title tridentate ligand, C14H10N4O, N-(quinolin-8-yl)pyrazine-2-carboxamide (HL1), crystallizes with three independent molecules (A, B and C) in the asymmetric unit. All three molecules are relatively planar (r.m.s. deviations are 0.068, 0.055 and 0.06 Å, respectively), with the NH H atom forming three-centered (bifurcated) intramolecular N—H...N hydrogen bonds in each molecule. There is also an intramolecular C—H...O contact present in each molecule, involving the benzene ring of the quinoline unit and the amide carboxamide O atom. In the crystal, the three molecules stack in columns with the various molecules being linked by offset π-π interactions [intercentroid distances vary from 3.367 (5) to 3.589 (5) Å], forming layers parallel to the ab plane. The title complex, [Cu4(C42H44N8O16)]·2CH3OH, {hexa-μ-acetato-1:2κ2
O:O′;2:3κ8
O:O′;3:4κ2
O:O′-dimethanol-1κO,2κO-bis[N-(quinolin-8-yl)pyrazine-2-carboxamide]-1κ3
N,N′,N′′;4κ3
N,N′,N′′-tetracopper(II) methanol disolvate} (I), was obtained by the reaction of HL1 with Cu(CH3CO2)2. It consists of a tetranuclear complex with a central tetrakis(μ-acetato)dicopper paddle-wheel moiety linked on either side via bridging acetato ions to a mononuclear copper(II)–(L1) complex; it crystallizes as a methanol disolvate. The complex possesses inversion symmetry, being located about a center of symmetry situated at the mid-point of the Cu...Cu bond of the paddle-wheel moiety. In the crystal, the complex molecules are linked by O—H...O hydrogen bonds, forming chains along the [01\overline{1}] direction, which are linked by offset π–π interactions [intercentroid distance = 3.7367 (11) Å] and C—H...O hydrogen bonds, leading to the formation of a supramolecular framework.
Crystal structure and DFT study of (E)-2-chloro-4-{[2-(2,4-dinitrophenyl)hydrazin-1-ylidene]methyl}phenol acetonitrile hemisolvate
Authors: Dege Necmi , Faizi Md. Serajul Haque , Doğan Onur Erman , Ağar Erbil , Golenya Irina A.
Published: May 2019

The title Schiff base compound, C13H9ClN4O5·0.5CH3CN, crystallizes as an acetonitrile hemisolvate; the solvent molecule being located on a twofold rotation axis. The molecule is nearly planar, with a dihedral angle between the two benzene rings of 3.7 (2)°. The configuration about the C=N bond is E, and there is an intramolecular N—H...Onitro hydrogen bond present forming an S(6) ring motif. In the crystal, molecules are linked by O—H...O and N—H...O hydrogen bonds, forming layers lying parallel to (10\overline{1}). The layers are linked by C—H...Cl hydrogen bonds, forming a supramolecular framework. Within the framework there are offset π–π stacking interactions [intercentroid distance = 3.833 (2) Å] present involving inversion-related molecules. The DFT study shows that the HOMO and LUMO are localized in the plane extending from the phenol ring to the 2,4-dinitrobenzene ring, and the HOMO–LUMO gap is found to be 0.13061 a.u.
Crystal structure and Hirshfeld surface analysis of 4-[4-(1H-benzo[d]imidazol-2-yl)phenoxy]phthalonitrile dimethyl sulfoxide monosolvate
Authors: Demir Kanmazalp Sibel , Şen Pınar , Dege Necmi , Yildiz Salih Zeki , Ozdemir Namık , Golenya Irina A.
Published: May 2019

This work presents the synthesis and structural characterization of [4-(1H-benzo[d]imidazol-2-yl)phenoxy]phthalonitrile, a phthalonitrile derivative carrying a benzimidazole moiety. The compound crystallizes as its dimethyl sulfoxide monosolvate, C21H12N4O·(CH3)2SO. The dihedral angle between the two fused rings in the heterocyclic ring system is 2.11 (1)°, while the phenyl ring attached to the imidazole moiety is inclined by 20.7 (1)° to the latter. In the crystal structure, adjacent molecules are connected by pairs of weak intermolecular C—H...N hydrogen bonds into inversion dimers. N—H...O and C—H...O hydrogen bonds with R
2
1(7) graph-set motifs are also formed between the organic molecule and the disordered dimethyl sulfoxide solvent [occupancy ratio of 0.623 (5):0.377 (5) for the two sites of the sulfur atom]. Hirshfeld surface analysis and fingerprint plots were used to investigate the intermolecular interactions in the crystalline state.
1-[(1R*,2R*)-1,2-Dihydroxy-1,2-dihydronaphthalen-1-yl]ethan-1-one
Authors: Lough Alan J. , Hill Jarvis , Tam William
Published: May 2019

The crystal structure of the centrosymmetic title compound, C12H12O3, confirms the relative stereochemistry. The 1,2-dihydrobenzene ring is in a flattened half-chair conformation. In the crystal, O—H...O hydrogen bonds link the molecules into layers lying parallel to (001).
Marching with the volunteers
Authors: Dewi Miranti Kartika , Manochin Melina , Belal Ataur
Published: May 2019

Purpose

The purpose of this paper is to examine the role of volunteers and its impact on related accountability practices towards beneficiaries by a large humanitarian non-governmental organisation (NGO) in Indonesia.

Design/methodology/approach

The authors adopted a qualitative case study design. The empirical evidence comes from rich fieldwork carried out in an Indonesian NGO. The authors collected the evidence mainly via 46 interviews and five focus groups.

Findings

The authors found that the case NGO drew heavily on the social and cultural capitals of volunteers in the process of serving its beneficiaries, which, in turn, facilitated the enhancement of its accountability to the beneficiaries. The authors also found that volunteers play a bridging role to reduce the distance between NGOs and beneficiaries.

Research limitations/implications

For NGO managers, this study provides necessary empirical evidence on the positive role played by the volunteers in the development and operationalisation of accountability to the beneficiaries. In the authors’ case, beneficiary accountability is enhanced by the social conduct and practices performed by the NGO’s numerous volunteers. Beneficiary accountability is of significant concern to the policy makers too. This study shows that volunteers and NGO can work in a reciprocal relationship where social and cultural capital can be mobilised to each other’s advantage. To facilitate beneficiary accountability, NGOs can draw on the socio-cultural capitals held by the volunteers who appear to share the same norms and expectations with the beneficiaries. This process can also lead to the building of social and cultural capital by the volunteers themselves as they achieve great satisfaction and gain valuable experience in this process that could lead to greater satisfaction in their spiritual and material lives.

Originality/value

The authors extend the previous literature on beneficiary accountability by highlighting the under-researched role of volunteers in such accountability practices. In this paper, the authors first discuss the facilitating role of volunteers in enhancing NGOs’ accountability towards beneficiaries. Then, this is illustrated empirically. In addition, the authors argue that although Bourdieusian concepts like field and capital have been widely used in the analysis of various organisational practices the concept of habitus received limited attention particularly from the context of developing countries. The authors undertake an examination of the habitus of volunteers in the Indonesian case organisation and explore their linkages with the field and associated capitals.
How consumers’ brand experience in social media can improve brand perception and customer equity
Authors: Yu Xiaolei , Yuan Chunlin
Published: May 2019

Purpose

The purpose of this paper is to investigate factors driving consumers’ social media brand experience and its effect on customer equity and customer lifetime value (CLV). A conceptual model is proposed including the variables of product attributes, brand experience, brand attachment, brand trust, customer equity and CLV.

Design/methodology/approach

The proposed research model is analyzed using a survey of 708 South Korean and Chinese consumers.

Findings

The results indicate that utilitarian and hedonic values influence brand experience, and that brand experience directly influences brand attachment, brand trust and customer equity drivers. There is a positive relationship between brand attachment and trust. As a customer equity driver, brand equity has a positive effect on CLV.

Originality/value

This study sheds light on how brand experience in social media can improve customer equity. It contributes to the theory of brand experience and customer equity as well as smartphone product marketing strategies. From a managerial perspective, guidelines are provided for firms to implement value communication activities using social media, and to maintain and increase their CLV.
Comparison-based perceived attribute performance as a better antecedent of satisfaction, value and loyalty
Authors: Vera-Martinez Jorge , Ornelas Sidney
Published: May 2019

Purpose

Product performance measurements have been used to explain other business performance variables. The purpose of this paper is to propose that, regarding Mexican consumers, the “comparison-based perceived attribute performance” (CAP) approach is a better predictor of outcomes, such as satisfaction, value and loyalty, compared with the traditional measurement of “non-comparison-based perceived attribute performance” (NCAP). These two forms of assessing attribute-level performance may be considered as different constructs.

Design/methodology/approach

Using these two approaches, empirical tests were performed to attribute performance measurement and were conducted on products from two different categories: tequila and liquid dishwashing detergent. Regression analyses were performed using Mexican consumer samples ofn=295 andn=239, respectively.

Findings

As opposed to NCAP, CAP measurements yielded higher statistical levels of satisfaction, value and loyalty for both product categories. In the case of tequila, factor analysis indicated a clear separation between the two types of measurements, suggesting that they should be considered distinct constructs. However, this was not found for the other product category.

Originality/value

CAP, which has better potential to predict outcomes than NCAP, could have relevant implications in brand positioning assessment and importance-performance analyses.
The direct and indirect effects of anger and its cognitive appraisals in public relations incidents
Authors: Sung Billy , Yih Jennifer
Published: May 2019

Purpose

The purpose of this paper is to examine the predictive power of anger and its associated appraisal dimensions of consumer responses to two different public relations incidents.

Design/methodology/approach

A natural quasi-experiment was conducted within a month after the public relations incidents. Participants randomly viewed one of the two videos relating to the incidents. Path analysis was used to examine the direct and indirect effects of anger, acceptability appraisal, motivational incongruence appraisal, relevance appraisal and other accountability appraisal on consumers’ intention to harm the brand and future purchase intention.

Findings

Appraisals of acceptability, motivational incongruence and relevance, but not other accountability, have both direct and indirect effects on anger and its motivational tendency. Acceptability appraisal directly increases consumers’ intention to harm, whereas relevance appraisal directly increases their intention to harm and reduces future purchase intention. The degree to which these appraisal structure and anger occur account for the level of negative consumer responses toward the two public relations incidents.

Practical implications

The current findings empirically replicate the diverse consumer responses toward two public relations incidents and use anger and its appraisal structure to account for the negative responses. This provides researchers and practitioners a framework to explain and manage consumers’ reaction toward different public relations incidents.

Originality/value

The current findings not only support the motivational role of anger and its accompanying appraisals in public relations incidents, but also demonstrate their predictive power in the given contexts.
Do service firm employee and customer relations matter for customer forgiveness in service recovery?
Authors: Muhammad Lakhi , Gul-e-Rana Gul-e-Rana
Published: May 2019

Purpose

Customer forgiveness is gaining importance in service recovery. This study debates that service firm employees and the customers’ relations are supportive resources for the customer while deciding for forgiveness. Accordingly, the purpose of this paper is to test the effects of structural, relational and cognitive social capital on customer forgiveness and thereof the effects of customer forgiveness on negative word of mouth and repatronage intentions.

Design/methodology/approach

Partial least squares–structural equation modeling was employed to test the hypothesized relations on usable data from 428 banking customers who registered their complaint recently.

Findings

Results show that structural, relational and cognitive social capital explained a unique variance in customer forgiveness with significant positive influence, whereas customer forgiveness has a significant positive effect on repatronage intentions and a significant negative influence on negative word of mouth.

Originality/value

Customer forgiveness is a convincing idea in service recovery. This study proposed and empirically verified that social capital in relations of service firm employee and customer relations is important for customer forgiveness to minimize negative word of mouth and enhance repatronage intentions.
Exploring a suitable model of destination image
Authors: Jeong Yunduk , Kim Sukkyu
Published: May 2019

Purpose

The purpose of this paper is to investigate the structural relationships between destination image, tourist satisfaction, attitudinal loyalty and behavioral loyalty, with an emphasis on the mediating effect of tourist satisfaction on the relation between destination image and loyalty in the context of a small-scale recurring sporting event held in Asia.

Design/methodology/approach

Validity and reliability of the measurement scale were proved through a confirmatory factor analysis, Cronbach’s α analyses and correlation analyses. A structural equation modeling test with maximum likelihood estimation was conducted to test the relationships among the research variables using 440 participants.

Findings

The results revealed destination image had a direct influence on tourist satisfaction, attitudinal loyalty and behavioral loyalty, and that tourist satisfaction had a direct influence on attitudinal loyalty and behavioral loyalty. Moreover, tourist satisfaction was found to partially mediate relationships between destination image and attitudinal loyalty, and between destination image and behavioral loyalty.

Practical implications

First, destination marketers and organizers of a small event should provide tourists with an international or domestic newsletter of the small event. Second, destination marketers should place well-educated employees at popular hotels and restaurants and the event organizers should arrange that trained volunteers be positioned at stadiums, to enable tourists to find the locations of interest, which would help develop a positive image of the destination. Third, marketers and organizers should actively use social media to improve destination images and promote sporting events.

Originality/value

The authors offer a new perspective of tourist satisfaction as a mediating effect. Existing studies show tourist satisfaction fully mediates on the relation between destination image and loyalty, but the present study shows tourist satisfaction partially mediates this relation. In this respect, the term “sporting event” should be regarded important when attempting to understand tourist psychology and behavior because the level of tourist satisfaction can be affected by a term like “sporting event” in the mediating effect context.