bluuebunny/crossref_metadata_2025 huggingface dataset:
Pleistocene climate changes, and not agricultural spread, accounts for range expansion and admixture in the dominant grassland species Lolium perenne L.
Authors: Blanco‐Pastor José Luis , Manel Stéphanie , Barre Philippe , Roschanski Anna M. , Willner Evelin , Dehmer Klaus J. , Hegarty Mathew , Muylle Hilde , Ruttink Tom , Roldán‐Ruiz Isabel , Ledauphin Thomas , Escobar‐Gutiérrez Abraham , Sampoux Jean‐Paul
Published: May 2019

Aim

Grasslands have been pivotal in the development of herbivore breeding since the Neolithic and still represent the most widespread agricultural land use across Europe. However, it remains unclear whether the current large‐scale genetic variation of plant species found in natural grasslands of Europe is the result of human activities or natural processes.

Location

Europe.

Taxon

Lolium perenne L. (perennial ryegrass).

Methods

We reconstructed the phylogeographic history of L. perenne, a dominant grassland species, using 481 natural populations, including 11 populations of closely related taxa. We combined Genotyping‐by‐Sequencing (GBS) and pool‐Sequencing (pool‐Seq) to obtain high‐quality allele frequency calls of ~500 k SNP loci. We performed genetic structure analyses and demographic reconstructions based on the site frequency spectrum (SFS). We additionally used the same genotyping protocol to assess the genomic diversity of a set of 32 cultivars representative of the L. perenne cultivars widely used for forage purposes.

Results

Expansion across Europe took place during the Würm glaciation (12–110 kya), a cooling period that decreased the dominance of trees in favour of grasses. Splits and admixtures in L. perenne fit historical climate changes in the Mediterranean basin. The development of agriculture in Europe (7–3.5 kya), that caused an increase in the abundance of grasslands, did not have an effect on the demographic patterns of L. perenne. We found that most modern cultivars are closely related to natural diversity from north‐western Europe. Thus, modern cultivars do not represent the wide genetic variation found in natural populations.

Main conclusions

Demographic events in L. perenne can be explained by the changing climatic conditions during the Pleistocene. Natural populations maintain a wide genomic variability at continental scale that has been minimally exploited by recent breeding activities. This variability constitutes valuable standing genetic variation for future adaptation of grasslands to climate change, safeguarding the agricultural services they provide.
Identifying Key Success Factors for Social Enterprises Serving Base‐of‐Pyramid Markets through Analysis of Value Chain Complexities
Authors: Pal Raktim , Altay Nezih
Published: May 2019

There are people in this world who have little or no access to basic needs and they struggle financially, living on less than a handful of dollars a day. A better understanding of how to supply/serve the world's poor is needed. In this paper, through the lens of Porter's value chain framework we investigate the challenges and opportunities social enterprises face in base‐of‐pyramid (BoP) markets based on secondary data on 23 organizations. Our contribution is twofold: First, we analyze value chain complexities for the social enterprise based on the value creation role (consumer, coproducer) and income level (poverty, extreme poverty) of the local population. We find that nature of customers’ requirements varies across customer segments in the BoP markets and social enterprises face unique challenges in fulfilling such differentiated demand patterns. Second, we develop an affordability–accessibility framework that helps to identify the situations that may be favorable/unfavorable for social enterprises to meet the challenges in BoP markets. We make four propositions that social enterprises may use to cope with difficulties in affordability and accessibility. Our findings will be useful for such organizations to understand and design better supply chains for the base of pyramid.
Rapid growth and large body size in annual fish populations are compromised by density‐dependent regulation
Authors: Vrtílek Milan , Žák Jakub , Polačik Matej , Blažek Radim , Reichard Martin
Published: May 2019

We tested the effect of population density on maximum body size in three sympatric species of annual killifishes Nothobranchius spp. from African ephemeral pools. We found a clear negative effect of population density on body size, limiting their capacity for extremely fast development and rapid growth. This suggests that density‐dependent population regulation and the ephemeral character of their habitat impose contrasting selective pressures on the life history of annual killifishes.
Comparison of two methods of subcision Nokor and blunt blade in acne scars treatment
Authors: Asilian Ali , Faghihi Gita , Asemi Esfahani Alireza , Mokhtari Fatemeh , Nilforoushzadeh Mohammadali , Mozafarpoor Samaneh
Published: May 2019

Context

Subcision is a simple surgical method that can be effective in treatment of acne scars.

Aims

This study was conducted to evaluate and compare the two methods of Nokor needle and blunt blade (BB) subcision in treatment of acne scars.

Settings and design

This clinical trial study was conducted on 28 patients with acne scars.

Patients and methods

One side of the face was treated with BB subcision method, and the other side was treated with Nokor needle method. Followed up period was 6 months after treatment. Statistical Analysis Used: Data were analyzed by Statistical Package for the Social Sciences (version 20) software using independent sample t test, Mann‐Whitney test, Friedman test, and Fisher's exact test.

Results

In follow‐up period, the improvement of acne scars was comparable in both groups (P > 0.05). Complications were lower in BB method than another method (P < 0.05). The patient satisfaction was higher in BB method (P < 0.05).

Conclusions

Both of modalities offered similar improvement, but the complication rate was lower and the patient satisfaction was also higher in the BB method than another method.
The efficacy and safety of topical 5% methimazole vs 4% hydroquinone in the treatment of melasma: A randomized controlled trial
Authors: Gheisari Mehdi , Dadkhahfar Sahar , Olamaei Elham , Moghimi Hamid Reza , Niknejad Nasim , Najar Nobari Niloufar
Published: May 2019

Background

The management of melasma is still challenging, and new treatment modalities with favorable side effect profile are required. Methimazole, a peroxidase inhibitor, seems to have a beneficial effect in the management of melasma but there is a paucity of studies for evaluation of its efficacy. This double‐blinded trial was aimed to evaluate the efficacy and safety of methimazole vs hydroquinone 4% which is the gold standard treatment in the management of melasma.

Methods

Fifty patients with melasma were enrolled and randomly divided into two groups to receive 4% hydroquinone or 5% methimazole once daily for 8 weeks. Forty patients completed the study. The clinical response was assessed at 4th, 8th, and 12th weeks after treatment by MASI score, patient satisfaction, and physician scores.

Results

Both groups showed a reduction in the MASI score at the 8th week which was more significant in hydroquinone group but higher relapse rate was also observed in this group after discontinuing the drug. The side effects were similar between groups. Also, patient and physician satisfaction scores were also more in favor of hydroquinone 4%.

Conclusion

Methimazole could be an alternative treatment of melasma alone or in combination with other depigmenting drugs. Although not as effective as hydroquinone, the noncytotoxic and nonmutagenic aspects of methimazole may make it a promising alternative for the treatment of melasma.
Static allometry in two species of neotropical stalk‐eyed fly
Authors: Oliveira Vasconcelos A. C. , Barros de Carvalho C. J. , Pie M. R.
Published: May 2019

The eye stalk is a sexually selected trait that has evolved several times within true flies (Diptera). It has been suggested that selection on secondary sexual traits such as the eye stalk favors positive allometry (disproportionate increase in a trait in relation to body size), but it remains unclear how common positive allometry is in such traits compared with nonsexual traits. Although the morphological evolution of eye stalks has been extensively investigated in diopsids, little is known about the evolution of eye stalks in other dipteran families. Our study aimed to assess the allometric relationships of sexual and nonsexual traits in two species of the Neotropical ulidiid genus Plagiocephalus. We estimated the covariance between body size and eye stalks, and between body size and four other nonsexual morphological traits, in males and females of P. latifrons and P. lobularis. We found a significant positive scaling relationship between eye stalk length and body size in both species, representing the steepest allometric exponents ever observed in stalk‐eyed flies. However, our results also show evidence that positive allometry is not exclusive for exaggerated traits. Our findings also lend support to the hypothesis that the allometric intercept is subject to more variation during evolution than the allometric slope.
Camouflage
Authors: Cuthill I. C.
Published: May 2019

Animal camouflage has long been used to illustrate the power of natural selection, and provides an excellent testbed for investigating the trade‐offs affecting the adaptive value of colour. However, the contemporary study of camouflage extends beyond evolutionary biology, co‐opting knowledge, theory and methods from sensory biology, perceptual and cognitive psychology, computational neuroscience and engineering. This is because camouflage is an adaptation to the perception and cognition of the species (one or more) from which concealment is sought. I review the different ways in which camouflage manipulates and deceives perceptual and cognitive mechanisms, identifying how, and where in the sequence of signal processing, strategies such as transparency, background matching, disruptive coloration, distraction marks, countershading and masquerade have their effects. As such, understanding how camouflage evolves and functions not only requires an understanding of animal sensation and cognition, it sheds light on perception in other species.
Lecanicillium aphanocladii: snake venom phospholipases A2 and proteases as tools to prospect enzymatic inhibitors
Authors: Cardoso M.G.B. , Trento M.V.C. , Reis C.H. , Marcussi S. , Cardoso P.G.
Published: May 2019

Natural enzyme inhibitors have been widely described in literature because of its pharmacological and cosmetic applications. Fungi found in caves represent a promising source of bioactive substances that are still little explored scientifically. Thus, the present work evaluated the presence of enzymatic modulators in a filtrate obtained from the cultivation of the cave fungus Lecanicillium aphanocladii (Family: Cordycipitaceae). Snake venoms from Bothrops alternatus and Bothrops atrox were used as an enzymatic source for the induction of the phospholipase, proteolytic, thrombolytic, cytotoxic and coagulant activities. Compounds present in the fungal filtrate inhibited 50, 23·8, 26·6, 50·9 and 52·5% of the proteolytic, phospholipase, haemolytic, thrombolytic and coagulant activities respectively. The filtrate was not cytotoxic on erythrocytes, but induced partial dissolution of thrombi. Fungal enzyme inhibitors that have low or no toxicity and can be obtained on a large scale and at low cost are relevant in the medical-scientific context. Therefore, the inhibition of phospholipases A2 and proteases observed in the present work highlights the potential of fungal metabolites for the development of drugs that can be used in the treatment of haemostasis and inflammation-related disorders.

Significance and Impact of the Study

In this study, secondary metabolites synthesized by Lecanicillium aphanocladii, a fungus isolated from caves, demonstrated modulating action on proteases and phospholipases A2 present in snake venoms of the Bothrops genus, widely used as tools for the study of pathophysiology processes related to haemostasis and inflammation. The results suggest the possibility of future applications for these metabolites in the development of pharmaceuticals of medical-scientific interest.
Chronic Hepatitis E is associated with cholangitis
Authors: Beer Andrea , Holzmann Heidemarie , Pischke Sven , Behrendt Patrick , Wrba Fritz , Schlue Jerome , Drebber Uta , Neudert Barbara , Halilbasic Emina , Kreipe Hans , Lohse Ansgar , Sterneck Martina , Wedemeyer Heiner , Manns Michael , Dienes Hans P.
Published: May 2019

Background and Aims

Sporadic hepatitis E is an emerging indigenous disease in Europe induced by genotype 3 of the virus. While the disease takes an acute self‐limited course in immunocompetent individuals, under immunocompromised conditions chronic hepatitis E might develop. The histology of chronic hepatitis E has not been described in detail systematically.

Methods

Liver biopsies from 19 immunosuppressed patients with chronic hepatitis E were collected: 17 were organ transplant recipients, one had a CD4‐deficiency and one had received steroid therapy because of ulcerative colitis. Biopsies were processed with standard stains. Evaluation of histologic activity and fibrosis was performed according to Ishak. Additionally, immunohistochemistry with antibodies directed against open reading frame 2 and 3 of the virus was performed and liver biopsies were tested for hepatitis E virus RNA.

Results

Biochemical data showed an increase in alanine transaminase, aspartate transaminase, gamma‐glutamyl transferase and total bilirubin. Histopathology displayed typical features of chronic hepatitis with mild to moderate activity. The number of polymorphonuclear leucocytes was considerably increased and all patients had a florid cholangitis that presented as a destructive form in five of them. Hepatocytes and bile duct epithelia stained positive for hepatitis E virus by immunohistochemistry.

Conclusions

Chronic hepatitis E in immunocompromised individuals runs a similar course as hepatitis B and C and shows similar histopathology. However, the presence of destructive cholangitis in some cases accompanied by an increased number of polymorphonuclear leucocytes is markedly different. Immunohistochemically the virus is present in bile duct epithelia, seemingly the cause for cholangitis.
Dissimilarities across age groups in the associations between complementary feeding practices and child growth: Evidence from rural Togo
Authors: Briaux Justine , Fortin Sonia , Kameli Yves , Agboka Yawavi , Romedenne Magali , Boko Joachim , Martin‐Prevel Yves , Becquet Renaud , Savy Mathilde
Published: May 2019

Adequate complementary feeding (CF) practices are essential for achieving optimal growth but challenging to measure comprehensively. This paper describes CF practices in 2,034 children aged 6–23 months and investigates their relationships with length‐for‐age z‐score (LAZ) and stunting, using cross‐sectional data collected from May to July 2014 in rural Northern Togo. The World Health Organization infant and young child feeding indicators were computed, along with ancillary indicators on feeding style and timing of introduction of complementary foods. The associations between those indicators and children's LAZ and stunting were assessed using linear and logistic regressions after stratification by age group and adjustment for children, maternal, and household characteristics. CF practices were suboptimal, and their associations with child's growth varied across indicators and age groups. In children aged 6–11 months, reaching the minimum dietary diversity and the minimum acceptable diet was associated with higher LAZ (p < .05). In 18‐ to 23‐month‐old children, only the consumption of iron‐rich food was associated with both LAZ (p = .02) and stunting (p = .05). The late introduction of family foods was associated with higher odds of being stunted and lower LAZ in children aged 12–17 months (p < .001). The untimely introduction of porridge was associated with higher odds of stunting in children aged 9–23 months (p < .05). Unexpectedly, helping the child to eat was negatively associated with linear growth in all age groups. These findings nurture the ongoing process of review of the World Health Organization infant and young child feeding indicators showing that, in their current version, they hardly capture the links between CF and child's growth at different ages.
Cyclic di‐GMP inactivates T6SS and T4SS activity in Agrobacterium tumefaciens
Authors: McCarthy Ronan R. , Yu Manda , Eilers Kira , Wang Yi‐Chieh , Lai Erh‐Min , Filloux Alain
Published: May 2019

The Type VI secretion system (T6SS) is a bacterial nanomachine that delivers effector proteins into prokaryotic and eukaryotic preys. This secretion system has emerged as a key player in regulating the microbial diversity in a population. In the plant pathogen Agrobacterium tumefaciens, the signalling cascades regulating the activity of this secretion system are poorly understood. Here, we outline how the universal eubacterial second messenger cyclic di‐GMP impacts the production of T6SS toxins and T6SS structural components. We demonstrate that this has a significant impact on the ability of the phytopathogen to compete with other bacterial species in vitro and in planta. Our results suggest that, as opposed to other bacteria, c‐di‐GMP turns down the T6SS in A. tumefaciens thus impacting its ability to compete with other bacterial species within the rhizosphere. We also demonstrate that elevated levels of c‐di‐GMP within the cell decrease the activity of the Type IV secretion system (T4SS) and subsequently the capacity of A. tumefaciens to transform plant cells. We propose that such peculiar control reflects on c‐di‐GMP being a key second messenger that silences energy‐costing systems during early colonization phase and biofilm formation, while low c‐di‐GMP levels unleash T6SS and T4SS to advance plant colonization.
Evolutionary couplings of amino acid residues reveal structure and function of bacterial signaling proteins
Authors: Szurmant Hendrik
Published: May 2019

The genomic era along with major advances in high‐throughput sequencing technology has led to a rapid expansion of the genomic and consequently the protein sequence space. Bacterial extracytoplasmic function sigma factors have emerged as an important group of signaling proteins in bacteria involved in many regulatory decisions, most notably the adaptation to cell envelope stress. Their wide prevalence and amplification among bacterial genomes has led to sub‐group classification and the realization of diverse signaling mechanisms. Mathematical frameworks have been developed to utilize extensive protein sequence alignments to extract co‐evolutionary signals of interaction. This has proven useful in a number of different biological fields, including de novo structure prediction, protein–protein partner identification and the elucidation of alternative protein conformations for signal proteins, to name a few. The mathematical tools, commonly referred to under the name ‘Direct Coupling Analysis’ have now been applied to deduce molecular mechanisms of activation for sub‐groups of extracytoplasmic sigma factors adding to previous successes on bacterial two‐component signaling proteins. The amplification of signal transduction protein genes in bacterial genomes made them the first to be amenable to this approach but the sequences are available now to aid the molecular microbiologist, no matter their protein pathway of interest.
Plant essential oils synergize various pyrethroid insecticides and antagonize malathion in Aedes aegypti
Authors: Norris E. J. , Gross A. D. , Bartholomay L. C. , Coats J. R.
Published: May 2019

Pyrethroid resistance is a significant threat to agricultural, urban and public health pest control activities. Because economic incentives for the production of novel active ingredients for the control of public health pests are lacking, this field is particularly affected by the potential failure of pyrethroid‐based insecticides brought about by increasing pyrethroid resistance. As a result, innovative approaches are desperately needed to overcome insecticide resistance, particularly in mosquitoes that transmit deadly and debilitating pathogens. Numerous studies have demonstrated the potential of plant essential oils to enhance the efficacy of pyrethroids. The toxicity of pyrethroids combined with plant oils is significantly greater than the baseline toxicity of either oils or pyrethroids applied alone, which suggests there are synergistic interactions between components of these mixtures. The present study examined the potential of eight plant essential oils applied in one of two concentrations (1% and 5%) to enhance the toxicity of various pyrethroids (permethrin, natural pyrethrins, deltamethrin and β‐cyfluthrin). The various plant essential oils enhanced the pyrethroids to differing degrees. The levels of enhancement provided by combinations of plant essential oils and pyrethroids in comparison with pyrethroids alone were calculated and synergistic outcomes characterized. Numerous plant essential oils significantly synergized a variety of pyrethroids; type I pyrethroids were synergized to a greater degree than type II pyrethroids. Eight plant essential oils significantly enhanced 24‐h mortality rates provided by permethrin and six plant essential oils enhanced 24‐h mortality rates obtained with natural pyrethrins. By contrast, only three plant essential plants significantly enhanced the toxicity of deltamethrin and β‐cyfluthrin. Of the plant essential oils that enhanced the toxicity of these pyrethroids, some produced varying levels of synergism and antagonism. Geranium, patchouli and Texas cedarwood oils produced the highest levels of synergism, displaying co‐toxicity factors of > 100 in some combinations. To assess the levels of enhancement and synergism of other classes of insecticide, malathion was also applied in combination with the plant oils. Significant antagonism was provided by a majority of the plant essential oils applied in combination with this insecticide, which suggests that plant essential oils may act to inhibit the oxidative activation processes within exposed adult mosquitoes.
Quality of life and psychological morbidity in patients with superficial cutaneous dermatophytosis
Authors: Narang Tarun , Bhattacharjee Rajsmita , Singh Shubhmohan , Jha Krishna , Kavita  , Mahajan Rahul , Dogra Sunil
Published: May 2019

We are facing an onslaught of chronic and recurrent dermatophytosis in epidemic proportions never encountered previously. There is a dearth of studies assessing the quality of life (QoL) and psychological morbidity in patients with superficial dermatophytosis. Our aim was to assess QoL and psychological morbidity in a sample of Indian patients suffering from dermatophytosis by using Dermatology Life Quality Index (DLQI) questionnaire and General Health Questionnaire (GHQ), respectively. This was a single‐centre, cross‐sectional study where consecutive patients of first episode, chronic or recurrent dermatophytosis were invited to participate. In addition to DLQI and GHQ12, patients' demographic data, duration and symptoms of dermatophyte infection, were also documented and recorded in the case record form. We recruited 196 patients who satisfied the inclusion criteria. The mean total DLQI score was 13.41 ± 7.56 (range 0‐30). The main items in the questionnaire influenced by the disease were “symptoms and feelings,” followed by “daily activities,” “leisure” and “personal relationships.” Age of the patient and body surface area involved had a significant impact on the QoL in our study (P ≤ 0.05). The mean GHQ‐12 score was 16.98; 84.9% of patients had a score higher than or equal to 12 indicating significant psychological distress. GHQ‐12 was found to have significant correlation with the DLQI score. Quality of life issues and psychosocial aspect should be considered while managing dermatophytosis as education about the disease, its management and prognosis may go a long way in improving the adherence to treatment and overall outcome in these patients.
Anatomical and ontogenetic reassessment of the Ediacaran frondArborea arboreaand its placement within total group Eumetazoa
Authors: Dunn Frances S. , Liu Alexander G. , Gehling James G.
Published: May 2019

Organisms in possession of a frondose body plan are amongst the oldest and most enigmatic members of the soft‐bodied Ediacaran macrobiota. Appraisal of specimens from the late Ediacaran Ediacara Member of South Australia reveals that the frondose taxonArborea arboreaprobably possessed a fluid‐filled holdfast disc, the size and form of which could vary within populations. Mouldic preservation of internal anatomical features provides evidence for tissue differentiation, and for bundles of tubular structures within the stalk of the organism. These structures connect in a fascicled arrangement to individual lateral branches, before dividing further into individual units housed on those branches. The observed fascicled branching arrangement, which seemingly connects individual units to the main body of the organism, is consistent with a biologically modular construction forArborea, and raises the possibility of a colonial organization. In conjunction with morphological characters previously recognized by other authors, including apical‐basal and front‐back differentiation, we propose that to the exclusion of all alternative known possibilities,Arboreacan be resolved as a total group eumetazoan.
Bereavement care in Japanese pediatrics: Pediatrician awareness in practice
Authors: Fujita Ayaka , Hamada Yuko
Published: May 2019

Background

A child's death affects not only family members but also the health‐care professionals involved in patient care. The education system for bereavement care in Japan, however, is not set up in a systematic way, and the care provided is based on the individual experience of the health‐care professional. The aim of this study was to investigate pediatrician awareness of and actual circumstances involved in bereavement care in Japan.

Methods

A qualitative descriptive study was conducted at four facilities in Japan. Data collected using semi‐structured interviews of 11 pediatricians were assessed using inductive qualitative analysis.

Results

Pediatrician recognition of the elements of bereavement care was categorized as follows: (i) developing relationships with families before a child's death is important in bereavement care; (ii) after the child dies, family involvement is left to the doctor's discretion; (iii) coping with a child's death myself through past experience is essential; (iv) doctors involved in a child's death also experience mental burden; and (v) a system for the family's bereavement care must be established. Two categories were established according to actual circumstances involved in bereavement care: (i) attention must be given to the emotions of the families who lost a child; and (ii) doctor involvement with bereaved families depends on doctor awareness and expertise.

Conclusion

Japanese pediatricians provided bereavement care to families who lost their children in a non‐systematic manner. This is necessitates improvement of the self‐care of health‐care professionals with regard to grief by improving bereavement care‐related education. Additionally, health‐care professionals must be trained, and a national‐level provision system must be established to provide high‐quality bereavement care to families who lose a child.
Laboratory values in Japanese children with newly diagnosed inflammatory bowel disease
Authors: Takaki Yugo , Mizuochi Tatsuki , Eda Keisuke , Ishihara Jun , Yamashita Yushiro
Published: May 2019

Background

Laboratory data in children with newly diagnosed inflammatory bowel disease (IBD) have been reported from Europe and North America, but not Asia. The aim of this study was to clarify laboratory data in Japanese children with newly diagnosed IBD, and to compare them with those in Western reports.

Methods

We retrospectively reviewed patients <16 years old, newly diagnosed with ulcerative colitis (UC) or Crohn's disease (CD) at Kurume University Hospital between January 2008 and December 2015.

Results

UC and CD patients numbered 31 and 15, respectively. The percentages of patients with normal values for hemoglobin (Hb), platelet count (Plt), albumin (Alb), C‐reactive protein (CRP), and erythrocyte sedimentation rate (ESR) in the UC and CD groups were 45% and 47%; 68% and 53%; 84% and 40%; 81% and 7%; and 35% and 0%, respectively. The frequency of normal results for these five tests were similar to Western findings except for the greater frequency of normal CRP in UC. Alb and ESR differed significantly between UC and CD in both mild and moderate–severe cases. Plt, Alb, CRP, and ESR differed significantly between diseases in late‐onset IBD, whereas early onset IBD showed no differences. In UC, ESR correlated positively, while Hb and Alb correlated negatively, with disease activity. In CD, CRP and ESR correlated positively with activity.

Conclusions

The proportion of Japanese children with IBD having normal values at diagnosis was mostly similar to that in Western reports. In early onset cases, UC parameters may be similar to CD. Of the five tests, ESR was particularly indicative of disease activity at diagnosis in both pediatric UC and CD.
Enzyme‐mediated metabolism in nutritive tissues of galls induced by Ditylenchus gallaeformans (Nematoda: Anguinidae)
Authors: Ferreira B. G. , Freitas M. S. C. , Bragança G. P. , Moreira A. S. F. P. , Carneiro R. G. S. , Isaias R. M. S.
Published: May 2019

The galls induced by Ditylenchus gallaeformans (Nematoda) on leaves of Miconia albicans have unique features when compared to other galls. The nematode colonies are surrounded by nutritive tissues with promeristematic cells, capable of originating new emergences facing the larval chamber, and providing indeterminate growth to these galls. Considering enzyme activity as essential for the translocation of energetic molecules from the common storage tissue (CST) to the typical nutritive tissue (TNT), and the major occurrence of carbohydrates in nematode galls, it was expected that hormones would mediate sink strength relationships by activating enzymes in indeterminate growth regions of the galls.

Histochemical, immunocytochemical and quantitative analyses were made in order to demonstrate sites of enzyme activity and hormones, and comparative levels of total soluble sugars, water soluble polysaccharides and starch.

The source–sink status, via carbohydrate metabolism, is controlled by the major accumulation of cytokinins in totipotent nutritive cells and new emergences. Thus, reducing sugars, such as glucose and fructose, accumulate in the TNT, where they supply the energy for successive cycles of cell division and for nematode feeding. The histochemical detection of phosphorylase and invertase activities indicates the occurrence of starch catabolism and sucrose transformation into reducing sugars, respectively, in the establishment of a gradient from the CST towards the TNT. Reducing sugars in the TNT are important for the production of new cell walls during the indeterminate growth of the galls, which have increased levels of water‐soluble polysaccharides that corroborate such a hypothesis.

Functional relationship between plant hormone accumulation, carbohydrate metabolism and cell differentiation in D. gallaeformans‐induced galls is attested, providing new insights on cell development and plant metabolism.
Improving water use efficiency by changing hydraulic and stomatal characteristics in soybean exposed to drought: the involvement of nitric oxide
Authors: de Sousa Letícia F. , de Menezes‐Silva Paulo E. , Lourenço Lucas L. , Galmés Jeroni , Guimarães Aline C. , da Silva Aline F. , dos Reis Lima Ana P. , Henning Liliane M. M. , Costa Alan C. , Silva Fabiano G. , Farnese Fernanda dos Santos
Published: May 2019

A variety of cellular responses is needed to ensure the plants survival during drought, but little is known about the signaling mechanisms involved in this process. Soybean cultivars (EMBRAPA 48 and BR 16, tolerant and sensitive to drought, respectively) were exposed to the following treatments: control conditions (plants in field capacity), drought (20% of available water in the soil), sodium nitroprusside (SNP) treatment (plants irrigated and treated with 100‐µM SNP [SNP–nitric oxide (NO) donor molecule], and Drought + SNP (plants subjected to drought and SNP treatment). Plants remained in these conditions until the reproductive stage and were evaluated for physiological (photosynthetic pigments, chlorophyll a fluorescence and gas exchange rates), hydraulic (water potential, osmotic potential and leaf hydraulic conductivity) and morpho‐anatomical traits (biomass, venation density and stomatal characterization). Exposure to water deficit considerably reduced water potential in both cultivars and resulted in decrease in photosynthesis and biomass accumulation. The addition of the NO donor attenuated these damaging effects of water deficit and increased the tolerance index of both cultivars. The results showed that NO was able to reduce plant's water loss, while maintaining their biomass production through alteration in stomatal characteristics, hydraulic conductivity and the biomass distribution pattern. These hydraulic and morpho‐anatomical alterations allowed the plants to obtain, transport and lose less water to the atmosphere, even in water deficit conditions.
Pyruvate and lactate as local prognostic biomarkers of patient outcome after achilles tendon rupture
Authors: Addevico Francesco , Svedman Simon , Edman Gunnar , Ackermann Paul W.
Published: May 2019

Background

Acute Achilles tendon rupture (ATR) is a frequently disabling injury, which exhibits unclear variability in long‐term functional and patient‐reported outcomes. Biomarkers from early healing, which have been shown to be prognostic of long‐term outcome would facilitate the development of improved treatment methods.

Hypothesis/Purpose

The aim of this study was to assess essential metabolites pyruvate and its product lactate, as early biomarkers in relation to long‐term functional‐ and patient‐reported outcome after ATR.

Study design

Prospective cohort study.

Methods

A total of 124 patients (103 men, 21 women; mean age 40 ± 7 years) with ATR, treated with uniform anesthetic and surgical technique, were prospectively assessed. At two weeks post‐injury pyruvate and lactate concentrations were assessed in both the injured and uninjured limbs using microdialysis followed by enzymatic quantification. The ratios of the concentration in the injured versus uninjured limb of pyruvate (pyruvate‐r) and lactate (lactate‐r) were calculated as well as the lactate/pyruvate ratios (L/P‐r). At 12 months, patient‐reported outcome was examined using self‐reported questionnaires; Achilles tendon Total Rupture Score (ATRS), Foot and Ankle Outcome Score (FAOS), and physical activity score. At 12 months, functional outcome was studied using the validated heel‐rise test.

Results

Elevated pyruvate‐r, at two weeks, was significantly associated with total ATRS (R = 0.254, P = 0.028), less loss in physical activity (R = 0.241, P = 0.039), less experience of pain in FAOS (R = 0.275, P = 0.032), and a higher number of heel‐rise repetitions on injured side (R = 0.230, P = 0.040) at 12 months. Increased lactate‐r was related with less strength limitations in the calf (R = 0.283, P = 0.011), while the elevated lactate‐pyruvate ratio, notably, was related to more limitations in walking on uneven surface (R = −0,243, P = 0.027). The findings were verified by multiple linear regression taking confounding factors into consideration.

Conclusion

This study established that the metabolite pyruvate is a good potential biomarker, prognostic of patient outcome at the one‐year follow‐up after ATR surgery. These novel findings suggest that local biomarkers could be developed at an early‐stage screen for new ATR treatments.
A mathematical model to describe survival among liver recipients from deceased donors with risk of transmitting infectious encephalitis pathogens
Authors: Smalley Hannah K. , Anand Nishi , Buczek Dylan , Buczek Nicholas , Lin Timothy , Rajore Tanay , Wacker Muriel , Basavaraju Sridhar V. , Gurbaxani Brian M. , Hammett Teresa , Keskinocak Pinar , Sokol Joel , Kuehnert Matthew J.
Published: May 2019

Background

Between 2002 and 2013, the organs of 13 deceased donors with infectious encephalitis were transplanted, causing infections in 23 recipients. As a consequence, organs from donors showing symptoms of encephalitis (increased probability of infectious encephalitis (IPIE) organs) might be declined. We had previously characterized the risk of IPIE organs using data available to most transplant teams and not requiring special diagnostic tests. If the probability of infection is low, the benefits of a transplant from a donor with suspected infectious encephalitis might outweigh the risk and could be lifesaving for some transplant candidates.

Methods

Using organ transplant data and Cox Proportional Hazards models, we determined liver donor and recipient characteristics predictive of post‐transplant or waitlist survival and generated 5‐year survival probability curves. We also calculated expected waiting times for an organ offer based on transplant candidate characteristics. Using a limited set of actual cases of infectious encephalitis transmission via transplant, we estimated post‐transplant survival curves given an organ from an IPIE donor.

Results

54% (1256) of patients registered from 2002‐2006 who died or were removed from the waiting list because of deteriorated condition within 1 year could have had an at least marginal estimated benefit by accepting an IPIE liver with some probability of infection, with the odds increasing to 86% of patients if the probability of infection was low (5% or less). Additionally, 54% (1252) were removed from the waiting list prior to their estimated waiting time for a non‐IPIE liver and could have benefited from an IPIE liver.

Conclusion

Improved allocation and utilization of IPIE livers could be achieved by evaluating the patient‐specific trade‐offs between (a) accepting an IPIE liver and (b) remaining on the waitlist and accepting a non‐IPIE liver after the estimated waiting time.
Remission of Epstein‐Barr virus‐positive post‐transplant lymphoproliferative disorder by conversion to everolimus in a kidney transplant recipient
Authors: Nanmoku Koji , Shinzato Takahiro , Kubo Taro , Shimizu Toshihiro , Yagisawa Takashi
Published: May 2019

Post‐transplant lymphoproliferative disorder (PTLD) is a fatal complication of transplantation. There is no clear consensus on the treatment of PTLD. In most cases, the pathogenetic mechanism of PTLD involves the Epstein‐Barr virus (EBV). We report the case of an elderly kidney transplant recipient who developed EBV‐positive monomorphic T‐cell PTLD 14 years after transplantation. Conversion from conventional immunosuppressants to everolimus induced complete remission of PTLD accompanied by a decrease in blood EBV‐DNA level without chemotherapy.
Design, Fabrication, and Performance Evaluation of a Hybrid Wick Vapor Chamber
Authors: Zhou Feng , Liu Yanghe , Dede Ercan M.
Published: May 2019

The growing electrification of transportation systems is dramatically increasing the waste heat that must be dissipated from high-density power electronics. Transformative embedded heat spreading technologies must be developed in next-generation systems to enable air cooling of power semiconductors with heat fluxes exceeding 500 W/cm2 over large hotspot areas up to 1 cm2. In this study, vapor chamber heat spreaders, or thermal ground planes (TGPs), with customized wick structures are investigated as one possibility. A 10 cm × 10 cm TGP with hybrid wick, which is a blend of a biporous wick with a standard monoporous wick, was designed. The TGP was tested in combination with a straight pin fin heat sink under air jet impingement and a 1 cm2 size heat source. The experimental performance of the hybrid wick TGP was compared under the same air-cooled conditions with an off-the-shelf TGP of the same size from a commercial vendor and a TGP with a biporous wick only. The customized hybrid wick TGP exhibits ∼28% lower thermal resistance compared with a traditional commercial TGP, and the capillary limit heat flux is measured as 450 W/cm2. Technical challenges in extending this capillary limit heat flux value and TGP integration into packaged electronics are described.
Experimental Study of Flow Structure Characteristics for a T-Junction Duct With Horizontal Vanes
Authors: Li Shicong , Wang Xiaoyu , He Jing , Lin Mei , Ke Hanbing
Published: May 2019

An experimental study is carried out to investigate the flow characteristics of the trailing edge of the horizontal vanes mounted at the branch entrance of a T-junction duct by means of particle image velocimetry (PIV). The measured region starts at the trailing edge of the vanes and ends at about 1.26D (hydraulic diameter) length at downstream of the branch duct. The velocity field is obtained across a number of vertical height planes (z/D = ±0.2, 0, and −0.4) under different flow conditions (cross velocity: uc = 30–50 m/s; velocity ratio: R = 0.08–0.18). The instantaneous flow results show that Kelvin-like vortices with counter-clockwise direction appear at the heights of z/D = ±0.2 and 0, and that a separation bubble is formed at the upper wall of the branch duct at the same heights, respectively. As for near wall z/D = −0.4, one large vortex is observed at the downstream channel, but the separation bubble vanishes as the branching Reynolds number is increased to 3.6 × 104. The time-average flow field is slightly different from that of instantaneous flow field. In addition, the vorticity distribution indicates that two significant vortex sheet layers with negative and positive values are found at the high velocity ratio or high cross velocity, and the normalized vorticity strength increases with increasing velocity ratio and decreases with increasing cross velocity except at z/D = −0.4.
Calibration and Validation of Hydrodynamics and Salinity Transport Model for Sabine Lake Water System
Authors: Wang Hairui , Zhang Ning
Published: May 2019

In this study, a hydrodynamic and a salinity transport models were developed for simulations of Sabine Lake water system located on the Texas-Louisiana border. The target simulation area includes several major water bodies, such as Sabine Lake, Sabine River, Sabine Pass, Sabine Neches Canal (Ship Channel), and part of Gulf Intracoastal Waterway (GIWW) and Sabine River Diversion Canal (SRDC). The SRDC supplies fresh water to the area industry, mainly petrochemical. High salinity in SRDC could significantly affect the daily production of the industry. Two-dimensional (2D) depth-averaged shallow water equation set and 2D depth-averaged salinity transport equation were used for developing the hydrodynamic and salinity transport numerical models in order to carry out the simulation. The major purposes of this study are to calibrate and validate hydrodynamic and salinity transport models in order to assess and predict the salinity in SRDC under severe weather conditions such as hurricane storm surges in future study. Measurement data from National Oceanic and Atmospheric Administration (NOAA) and United States Geological Survey (USGS) were used to calibrate the boundary conditions as well as to validate the model. Boundary conditions were calibrated at locations in Sabine Pass and in the north edge of the lake by using water–surface elevation data. Hydrodynamic model was validated at the USGS location using water–surface elevation data. Then, the simulation estimations of water surface level and salinity were compared at three locations, and the results show the accuracy of the validated model. Parallel computing was conducted in this study as well, and computational efficiency was compared.
Estimating Physics Models and Quantifying Their Uncertainty Using Optimization With a Bayesian Objective Function
Authors: Andrews Stephen A. , Fraser Andrew M.
Published: May 2019

This paper reports a verification study for a method that fits functions to sets of data from several experiments simultaneously. The method finds a maximum a posteriori probability estimate of a function subject to constraints (e.g., convexity in the study), uncertainty about the estimate, and a quantitative characterization of how data from each experiment constrains that uncertainty. While this work focuses on a model of the equation of state (EOS) of gasses produced by detonating a high explosive, the method can be applied to a wide range of physics processes with either parametric or semiparametric models. As a verification exercise, a reference EOS is used and artificial experimental data sets are created using numerical integration of ordinary differential equations and pseudo-random noise. The method yields an estimate of the EOS that is close to the reference and identifies how each experiment most constrains the result.
Reducing the Risk of High Temperature Creep Failures in Refinery Service Component and Equipment
Authors: Subramanian Chidambaram
Published: May 2019

This paper highlights about the high temperature creep failures affecting refinery materials, structures, and components for which good operational practices, proper maintenance, and inspection are required to avoid major failures and to maintain safety of personnel and integrity of static equipment and to avoid unplanned shut down.
Molten Salt Reactor Xenon Analysis: Review and Decomposition
Authors: Price Terry J. , Chvala Ondrej , Taylor Zack
Published: May 2019

This document analyzes molten salt reactor (MSR) xenon theory and reviews the corpus of literature pertaining to it. A history of xenon behavior in MSRs is presented. Relevant literature is tabulated. Assumptions in MSR xenon theories are made explicit. The structure of graphite stringers is examined. The behavior of bubbles is investigated along with interfacial area perturbation in response to thermodynamic state perturbation. This document serves as an underpinning to further investigation into the MSR xenon theory.
Gamma and X-Ray Shielding Properties of Various Types of Steels
Authors: Manjunatha H. C. , Seenappa L.
Published: May 2019

We have calculated the gamma and X-ray shielding parameters such as mass attenuation coefficient, half value layer (HVL), tenth value layer (TVL), specific gamma ray constant, effective atomic number, and buildup factors in various steels. By studying these X-ray and gamma interaction parameters, we have selected the best steel which can be used for the X-ray and gamma shielding material. The steel type 20Mo-4 is having higher values of mass attenuation coefficient, specific gamma ray constant, effective atomic number, and buildup factor and smaller values of HVL and TVL. A detail analysis of X-ray/gamma interaction in the different steels reveals that the steel type (S15) 20Mo-4 is good absorption of both X-ray/gamma radiations.