bluuebunny/crossref_metadata_2025 huggingface dataset:
Electron transport chain biogenesis activated by a JNK-insulin-Myc relay primes mitochondrial inheritance in Drosophila
Authors: Wang Zong-Heng , Liu Yi , Chaitankar Vijender , Pirooznia Mehdi , Xu Hong
Published: October 2019

Oogenesis features an enormous increase in mitochondrial mass and mtDNA copy number, which are required to furnish mature eggs with an adequate supply of mitochondria and to curb the transmission of deleterious mtDNA variants. Quiescent in dividing germ cells, mtDNA replication initiates upon oocyte determination in the Drosophila ovary, which necessitates active mitochondrial respiration. However, the underlying mechanism for this dynamic regulation remains unclear. Here, we show that an feedforward insulin-Myc loop promotes mitochondrial respiration and biogenesis by boosting the expression of electron transport chain subunits and of factors essential for mtDNA replication and expression, and for the import of mitochondrial proteins. We further reveal that transient activation of JNK enhances the expression of the insulin receptor and initiates the insulin-Myc signaling loop. This signaling relay promotes mitochondrial biogenesis in the ovary, and thereby plays a role in limiting the transmission of deleterious mtDNA mutations. Our study demonstrates cellular mechanisms that couple mitochondrial biogenesis and inheritance with oocyte development.
The yellow gene influences Drosophila male mating success through sex comb melanization
Authors: Massey Jonathan H , Chung Daayun , Siwanowicz Igor , Stern David L , Wittkopp Patricia J
Published: October 2019

Drosophila melanogaster males perform a series of courtship behaviors that, when successful, result in copulation with a female. For over a century, mutations in the yellow gene, named for its effects on pigmentation, have been known to reduce male mating success. Prior work has suggested that yellow influences mating behavior through effects on wing extension, song, and/or courtship vigor. Here, we rule out these explanations, as well as effects on the nervous system more generally, and find instead that the effects of yellow on male mating success are mediated by its effects on pigmentation of male-specific leg structures called sex combs. Loss of yellow expression in these modified bristles reduces their melanization, which changes their structure and causes difficulty grasping females prior to copulation. These data illustrate why the mechanical properties of anatomy, not just neural circuitry, must be considered to fully understand the development and evolution of behavior.
The Mars1 kinase confers photoprotection through signaling in the chloroplast unfolded protein response
Authors: Perlaza Karina , Toutkoushian Hannah , Boone Morgane , Lam Mable , Iwai Masakazu , Jonikas Martin C , Walter Peter , Ramundo Silvia
Published: October 2019

In response to proteotoxic stress, chloroplasts communicate with the nuclear gene expression system through a chloroplast unfolded protein response (cpUPR). We isolated Chlamydomonas reinhardtii mutants that disrupt cpUPR signaling and identified a gene encoding a previously uncharacterized cytoplasmic protein kinase, termed Mars1—for mutant affected in chloroplast-to-nucleus retrograde signaling—as the first known component in cpUPR signal transmission. Lack of cpUPR induction in MARS1 mutant cells impaired their ability to cope with chloroplast stress, including exposure to excessive light. Conversely, transgenic activation of cpUPR signaling conferred an advantage to cells undergoing photooxidative stress. Our results indicate that the cpUPR mitigates chloroplast photodamage and that manipulation of this pathway is a potential avenue for engineering photosynthetic organisms with increased tolerance to chloroplast stress.
Metabolic stress is a primary pathogenic event in transgenic Caenorhabditis elegans expressing pan-neuronal human amyloid beta
Authors: Teo Emelyne , Ravi Sudharshan , Barardo Diogo , Kim Hyung-Seok , Fong Sheng , Cazenave-Gassiot Amaury , Tan Tsze Yin , Ching Jianhong , Kovalik Jean-Paul , Wenk Markus R , Gunawan Rudiyanto , Moore Philip K , Halliwell Barry , Tolwinski Nicholas , Gruber Jan
Published: October 2019

Alzheimer’s disease (AD) is the most common neurodegenerative disease affecting the elderly worldwide. Mitochondrial dysfunction has been proposed as a key event in the etiology of AD. We have previously modeled amyloid-beta (Aβ)-induced mitochondrial dysfunction in a transgenic Caenorhabditis elegans strain by expressing human Aβ peptide specifically in neurons (GRU102). Here, we focus on the deeper metabolic changes associated with this Aβ-induced mitochondrial dysfunction. Integrating metabolomics, transcriptomics and computational modeling, we identify alterations in Tricarboxylic Acid (TCA) cycle metabolism following even low-level Aβ expression. In particular, GRU102 showed reduced activity of a rate-limiting TCA cycle enzyme, alpha-ketoglutarate dehydrogenase. These defects were associated with elevation of protein carbonyl content specifically in mitochondria. Importantly, metabolic failure occurred before any significant increase in global protein aggregate was detectable. Treatment with an anti-diabetes drug, Metformin, reversed Aβ-induced metabolic defects, reduced protein aggregation and normalized lifespan of GRU102. Our results point to metabolic dysfunction as an early and causative event in Aβ-induced pathology and a promising target for intervention.
Evolutionary loss of foot muscle during development with characteristics of atrophy and no evidence of cell death
Authors: Tran Mai P , Tsutsumi Rio , Erberich Joel M , Chen Kevin D , Flores Michelle D , Cooper Kimberly L
Published: October 2019

Many species that run or leap across sparsely vegetated habitats, including horses and deer, evolved the severe reduction or complete loss of foot muscles as skeletal elements elongated and digits were lost, and yet the developmental mechanisms remain unknown. Here, we report the natural loss of foot muscles in the bipedal jerboa, Jaculus jaculus. Although adults have no muscles in their feet, newborn animals have muscles that rapidly disappear soon after birth. We were surprised to find no evidence of apoptotic or necrotic cell death during stages of peak myofiber loss, countering well-supported assumptions of developmental tissue remodeling. We instead see hallmarks of muscle atrophy, including an ordered disassembly of the sarcomere associated with upregulation of the E3 ubiquitin ligases, MuRF1 and Atrogin-1. We propose that the natural loss of muscle, which remodeled foot anatomy during evolution and development, involves cellular mechanisms that are typically associated with disease or injury.
How chloroplasts protect themselves from unfolded proteins
Authors: Kessler Felix , Longoni Paolo
Published: October 2019

A genetic screen has identified the first signaling component of the unfolded protein response in chloroplasts.
Outline of an experimental design aimed to detect protein A mirror image in solution
Authors: Martin Osvaldo A. , Vorobjev Yury , Scheraga Harold A. , Vila Jorge A.
Published: October 2019

There is abundant theoretical evidence indicating that a mirror image of Protein A may occur during the protein folding process. However, as to whether such mirror image exists in solution is an unsolved issue. Here we provide outline of an experimental design aimed to detect the mirror image of Protein A in solution. The proposal is based on computational simulations indicating that the use of a mutant of protein A, namely Q10H, could be used to detect the mirror image conformation in solution. Our results indicate that the native conformation of the protein A should have a pKa, for the Q10H mutant, at ≈6.2, while the mirror-image conformation should have a pKa close to ≈7.3. Naturally, if all the population is in the native state for the Q10H mutant, the pKa should be ≈6.2, while, if all are in the mirror-image state, it would be ≈7.3, and, if it is a mixture, the pKa should be larger than 6.2, presumably in proportion to the mirror population. In addition, evidence is provided indicating the tautomeric distribution of H10 must also change between the native and mirror conformations. Although this may not be completely relevant for the purpose of determining whether the protein A mirror image exists in solution, it could provide valuable information to validate the pKa findings. We hope this proposal will foster experimental work on this problem either by direct application of our proposed experimental design or serving as inspiration and motivation for other experiments.
Influence of phylogenetic structure and climate gradients on geographical variation in the morphology of Mexican flycatcher forests assemblages (Aves: Tyrannidae)
Authors: Cortés-Ramírez Gala , Ríos-Muñoz César A. , Navarro-Sigüenza Adolfo G.
Published: October 2019

Morphological variation is strongly related to variation in the ecological characteristics and evolutionary history of each taxon. To explore how geographical variation in morphology is related to different climatic gradients and phylogenetic structure, we analyzed the variation of morphological traits (body size, bill, and wing) of 64 species of tyrant flycatchers (Tyrannidae) distributed in Mexico. We measured these morphological traits in specimens from biological collections and related them to the climatic and topographic data of each collection locality. We performed the analyses separately at two levels: (1) the regional level and (2) the assemblage level, which was split into (assemblage I) lowland forests and (assemblage II) highland forests and other vegetation types. We also calculated the phylogenetic structure of flycatchers of each locality in order to explore the influence of climatic variables and the phylogenetic structure on the morphological variation of tyrant flycatchers, by means of linear mixed-effects models. We mapped the spatial variation of the relationship between morphological traits and environmental gradients, taking into account the phylogenetic structure. Important climatic variables explaining the morphological variation were those of temperature ranges (seasonality) and the results suggest that the phylogenetic clustering increases towards the highlands of Sierra Madre Oriental and Sierra Madre del Sur, and the lowlands of Balsas Depression. For the regional level, the spatial distribution of body size showed a pattern coincident with Bergmann’s rule, with increasing in size from south to north. In the tropical lowland forests assemblage, body size tend to increase in seasonally dry forests (western Mexico) and decrease in the humid ones (eastern Mexico). In the assemblage of highland forests and other types of vegetation, morphological trait values increased northeast to southwest. Phylogenetic structure helped to explain the variation of morphology at the assemblage level but not at the regional level. The patterns of trait variation in the lowland and highland assemblages suggest that parts of morphological variation are explained both by the climatic gradients and by the lineage relatedness of communities. Overall, our results suggest that morphological variation is best explained by a varied set of variables, and that regression models representing this variation, as well as integrating phylogenetic patterns at different community levels, provide a new understanding of the mechanisms underlying the links among biodiversity, its geographical setting, and environmental change.
Phylogeny and biogeography of the African Bathyergidae: a review of patterns and processes
Authors: Visser Jacobus H. , Bennett Nigel C. , Jansen van Vuuren Bettine
Published: October 2019

Background

We review genealogical relationships, biogeographic patterns and broad historical drivers of speciation within the Bathyergidae, a group of endemic African rodents, as well as identify key taxa which need further research.

Methods

We sourced comparable cytochromebsequence data (comparable data available for all members for the Family) and geographic information for all six genera of the African subterranean rodent. This information was combined into the most comprehensive and geographically representative evolutionary study for the Bathyergidae to date.

Results

Species richness within the Bathyergidae appears to be underestimated, with undescribed taxa in five of the six genera. Biogeographic patterns suggest large historical distributions, which were repeatedly fragmented by major landscape changes (especially rifting, uplift and drainage evolution) since the Miocene. Aside from vicariant events, other factors (ecological specialization, population-level responses and climatic change) may have been instrumental in driving divergences in the Bathyergidae. As such, adaptive differences may exist among both populations and species across their discrete ranges, driving independent evolutionary trajectories among taxa. In addition, highly fragmented distributions of divergent (and often relict) lineages indicates the possibility of narrow endemics restricted to diminishing suitable habitats. From this, it is clear that a systematic revision of the Bathyergidae is necessary; such a revision should include comprehensive sampling of all putative taxa, the addition of genomic information to assess adaptive differences, as well as ecological information.
Urban-rural disparity in the utilization of national community-based hypertension monitoring service—results from the China Health and Retirement Longitudinal Study, 2015
Authors: Song Hongxun , Feng Da , Wang Ruoxi , Tang Shangfeng , Ghose Bishwajit , Li Gang , Chen Xiaoyu , Feng Zhanchun
Published: October 2019

Background

Since 2009, community-based hypertension monitoring service (CBHMS) has been provided free of charge by the Chinese government as part of the national Essential Public Health Services (EPHS) policy. This study aimed to examine the disparity in the utilization of CBHMS between urban and rural community-dwelling middle-aged and older adults with hypertension.

Methods

Subjects were 3,479 community-residing hypertensive patients, identified from the China Health and Retirement Longitudinal Study (CHARLS), 2015, a nationally representative survey of Chinese residents aged 45 years and older. The utilization of CBHMS was defined as having one’s blood pressure (BP) examined at least once a season by community or village doctors. Rates of CBHMS use of urban and rural residents with hypertension were compared by using chi-square test. Multiple logistic regression analyses were conducted to examine factors associated with the utilization of CBHMS of hypertensive patients.

Results

CBHMS was significantly more likely to be used by rural than urban middle-aged and older residents with hypertension (38.6% vs. 25.1%, P < 0.001). Results from multiple logistic regression analyses showed that urban patients who were living in central (OR = 0.37) and western (OR = 0.48) regions (vs. eastern region), had an educational attainment of middle school (OR = 0.33) and college and above (OR = 0.48) (vs. illiterate), and were not taking antihypertensive agents (OR = 0.26) were less likely to use CBHMS, while rural patients who had no medical insurance (OR = 0.56), and were not taking antihypertensive agents (OR = 0.31) were less likely to use CBHMS.

Conclusions

The national CBHMS is more likely to be used by rural middle-aged and older adults with hypertension in China. The urban-rural difference in the utilization of CBHMS may be resulted from the different demographics of urban and rural middle-aged and older residents and uneven distributions of health services resources between urban and rural areas. Urban-rural disparities in characteristics of CBHMS use should be taken into consideration when promoting the utilization of CBHMS in China.
Acacia × mangiiformis hybrida nova (Leguminosae: Mimosoideae), a wattle of commercial importance in Asia
Authors: Maslin Bruce , Thomson Lex AJ , Mabberley David
Published: October 2019

Acacia × mangiiformis Maslin & L.A.J.Thomson, hybrida nova, is described. Its parents are Acacia auriculiformis A.Cunn. ex Benth. and A. mangium Willd., two well-known and important plantation species in Asia and elsewhere. Acacia × mangiiformis arose naturally in the Western Province of Papua New Guinea and in recent decades has become widely cultivated in southeast Asia (Indonesia, Malaysia, Thailand and Vietnam), India, and to a lesser extent in China and Taiwan. The tree has often been referred to as “Acacia hybrid” in forestry literature. Acacia × mangiiformis has morphological and other characteristics that are intermediate between its parents. Furthermore, it often has a faster growth rate, superior bole form and is more drought-tolerant than its parent species The hybrid is used primarily for pulp production but also has uses as solid wood products and fuelwood. The wood is similar to that of A. mangium but has a higher density and is more suitable for products where strength is important; it is also less susceptible to termite attack than are its parent species. Ten high-performing commercial clones of Acacia × mangiiformis have been developed in Vietnam and more are being selected. The formal naming of this important hybrid is dedicated to Professor Le Dinh Kha (formerly of Forest Science Institute of Vietnam), an outstanding researcher, supervisor, and authority on tree breeding who conducted much of the original research and promotion of Acacia × mangiiformis in Vietnam.
Molecular and morphological evidence support the reinstatement of Cheilolejeunea comitans from synonymy of C. krakakammae.
Authors: Beveridge Peter , Shepherd Lara
Published: October 2019

In 2006 Cheilolejeunea comitans (Hook f. and Taylor) R.M.Schust., previously treated as endemic to New Zealand and Australia, was placed in synonymy of C. krakakammae (Lindenb.) R.M.Schust., a taxon with an African type. Here we generated DNA sequences from samples of New Zealand C. comitans and compared them with published sequences for C. krakakammae from China. The molecular evidence, together with a new analysis of morphological evidence from selected samples of C. comitans, and from the types and descriptions of C. krakakammae, justify the reinstatement of C. comitans.
A nomenclatural history for Plectorrhiza purpurata (Orchidaceae)
Authors: Renner Matthew AM
Published: October 2019

The nomenclatural history of the Australian epiphytic orchid Plectorrhiza purpurata (Rupp) M.A.M.Renner is reviewed. The first name published for this species, Cleisostoma gemmatum Rupp, is illegitimate, and Rupp proposed a replacement name, Cleisostoma purpuratum Rupp, shortly thereafter. Though the replacement was somewhat obliquely worded, Rupp fulfilled the requirements of the International Code of Nomenclature for algae, fungi, and plants, such that Cleisostoma purpuratum was available to serve as the basionym for the name generally used for this orchid since 1967, i.e. Schistotylus purpuratus (Rupp) Dockrill. The transfer of this taxon to Plectorrhiza under the new name Plectorrhiza gemmata M.A.Clem., D.L.Jones & D.P.Banks resulted in the publication of a superfluous name, because the earliest legitimate epithet purpurata is available in Plectorrhiza and ought to have been adopted. The required new combination is made.
The filmy fern Hymenophyllum reinwardtii (Hymenophyllaceae) newly recorded for Australia.
Authors: Renner Matthew AM , Field Ashley Raymond
Published: October 2019

The Malesian species Hymenophyllum reinwardtii is reported as a new record for Australia. This distinctive filmy fern can be recognized by the undulate and dentate lamina margins, the undulate and dentate rachis wing, and the circular indusial flaps whose margins are usually irregularly and sparsely denticulate or rarely entire. The species was collected in the vicinity of the summit of Mt Finnigan in June 2017, and is currently known in Australia by this one gathering.
Determination of Heavy Metals in Selected Tissues and Organs of Cattle from Central Abattoir in Ado-Ekiti, Akure and Owena
Authors: Momodu Daniel Uwaremhevho , Oyebanji Adedayo Olamide
Published: October 2019

This study was to determine the concentrations of lead (Pb), cadmium (Cd) and zinc (Zn) in the organs (liver, kidney and heart) and tissues (intestine and blood) of slaughtered cattle using spectroscopy method based on comparison with standards. The results obtained for these heavy metals have values that ranged from 0.00±0.00 to 7.33±5.01mg/kg for Pb, 0.00±0.00 to 0.50±0.50 mg/kg for Cd and 0.00±0.00 to 51.67±10.54 mg/kg for Zn. Generally, Zn was found to be present at the higher significant levels in the liver, heart, kidney and intestine. It was also found that there was no detection for Zn in the blood. Pb was found relatively high than the standard permissible limit by FAO/WHO [1] in the tissues. Cd was found to be present at the lowest concentration level. Hence, the concentrations of all the heavy metals were within the tolerance limits with the exception of Pb.
Comparison of Proposed and Existing Fourth Order Schemes for Solving Non-linear Equations
Authors: Rajput Khushbu , Shaikh Asif Ali , Qureshi Sania
Published: October 2019

This paper, investigates the comparison of the convergence behavior of the proposed scheme and existing schemes in literature. While all schemes having fourth-order convergence and derivative-free nature. Numerical approximation demonstrates that the proposed schemes are able to attain up to better accuracy than some classical methods, while still significantly reducing the total number of iterations. This study has considered some nonlinear equations (transcendental, algebraic and exponential) along with two complex mathematical models. For better analysis graphical representation of numerical methods for finding the real root of nonlinear equations with varying parameters has been included. The proposed scheme is better in reducing error rapidly, hence converges faster as compared to the existing schemes.
The Effect of Intervention with Acupressure Therapy on Improving Overall Male Sexual Performance
Authors: Bay Roohallah , Ahmadi Khodabakhsh , Fathi-Ashtiani Ali , Zarghami Mohammad Hossein
Published: October 2019

Background and Objective: The purpose of this study was to evaluate the efficacy of acupressure therapy on improving the overall male sexual performance.  Acupressure therapy is a therapeutic approach that assumes that throughout the body there are certain nerves that have a direct and close relationship with the tissues and organs and they can be stimulated.

 Method: This study was conducted in a semi-experimental and pre-test-post-test design with control group. The community of this research was from men living in Tehran who had been at least two years of their last permanent marriage and between the ages of 20 and 45 and living in Iran. In this study, the target points in reflexes and in other parts of the body were 2, 5, 8, 9, 11, 12, 14, 15, 16, 18, 28, 29, 33, 34. Measurement tool in this research was International index of erectile function.

Results: The findings of the study showed that the subjects in the acupressure group had an increase of 18.27% in the post-test and 18.6% in comparison with the pre-test in the overall sexual performance. The result of the study was that the intervention by acupressure therapy method had an impact on overall male sexual performance.

Conclusion: The results of this study indicate that interventions using acupressure therapy are effective in improving overall male sexual performance and it is possible to emphasize the need for more attention to psycho-physiological interventions, including the approach of acupressure therapy in the field of sexual issues.
Modeling Tree Mortality for Eucalyptus camaldulensis (Dehnh) Stands in Afaka Forest Reserve, Kaduna-Nigeria
Authors: Abubakar B. , Shamaki S. B. , Dantani A. , Gada Z. Y. , Gupa M. A.
Published: October 2019

This research was conducted to investigate mortality using logistic regression (Models) for River red-gum (Eucalyptud camaldulensis Dehnh) in Afaka Forest Reserve, Kaduna, Nigeria. Stratified random sampling and proportional sampling allocation were used in selecting plots and individual trees for measurements. Data on live and dead trees were recorded, variables measured are diameter, total tree heights, spacing and age of the stands within the plots. Diameter at the breast height (DBH) was measured using diameter tape while Haga Altimeter was used in taking the total height of the sampled stands. The Data collected were divided into four portions. Three portions (75%) for model calibration adopting logistic regression model, 25% were used for model validation of logistic model generated.  Chi square test of goodness-of-fit, Negelkerke R2, Cox and snell R2 values were used for model evaluation. The positive regression coefficients (16.737, 49.266 and 1.992) showed by Dbh, Height and age (as independent variables) indicated positive future mortality effects on the stands; as the trees ages and increases in size and height, the chances of mortality will increase. At the present age and sizes of the stands the fitted model shows no significant relationship between the current age, height and size of the stands, as such the notion held by the management of the plantation that Eucalyptus cannot grow for many years and in large sizes is not true. There is therefore, need for periodic re-measurement of the stands to evaluate future effect of the variables (Age, Dbh and height) on mortality.
Antigen Presentation to Lymphocytes
Authors: Muharemagic Darija , Scott William , Mishto Michele
Published: October 2019

Antigen presentation to T and B lymphocytes by antigen‐presenting cells plays a central role in the initiation and regulation of adaptive immune responses. T cells recognise peptides in the context of major histocompatibility complex (MHC) molecules via T cell receptors (TCRs). In contrast, B cells recognise and bind proteins via membrane‐bound immunoglobulins, known as B cell receptors (BCRs). Which epitopes are recognised by TCRs and BCRs has a major impact on the cell‐mediated immune response.

Key Concepts

T lymphocytes are key players in the adaptive immune response.

T lymphocytes need professional antigen‐presenting cells (APCs) to be primed.

Upon priming, T cell activation does not need professional APCs.

CD8+T cells mediate the cytotoxic response against infected cells.

CD8+T cells can mediate the cytotoxic response against cancer cells.

T cell receptor αβ (TCR αβ) recognises complexes formed by major histocompatibility complex (MHC) molecules and antigenic peptides.

After several steps of the antigen processing and presentation (APP) pathway, antigenic peptides are presented by MHC molecules to T cells.

An antigenic peptide that triggers a T cell activation is defined as an ‘epitope’.

Unconventional epitopes such as posttranslationally spliced epitopes can trigger a T cell response.
D
esulfoplanes
Authors: Watanabe Miho , Fukui Manabu , Kuever Jan
Published: October 2019

De.sul.fo.pla'nes. L. pref.
de
from; L. neut. n.
sulfur
sulfur; Gr. masc. n.
planes
a wanderer, roamer; N.L. masc. n.
Desulfoplanes
a sulfate‐reducing wanderer, pertaining to a motile sulfate reducer.

Desulfobacterota / Desulfovibrionia / Desulfovibrionales / Desulfoplanaceae / Desulfoplanes

Cells are vibrios, 1.0 µm × 3.0–4.0 µm, occur singly, in pairs or in chains. Spore formation is not observed. Stain Gram‐negative. Motile. Strict anaerobe with a respiratory or fermentative type of metabolism. Chemoorganoheterotrophic and chemolithoheterotrophic. Pyruvate, lactate, fumarate, and malate are used as electron donors and carbon sources and are incompletely oxidized to acetate. Growth on H
2
and formate requires acetate as an organic carbon source. Addition of yeast extract greatly enhances growth on formate, but it is not required for growth on other substrates. Sulfate, sulfite, and thiosulfate are used as terminal electron acceptors and are reduced to H
2
S. Nitrate is not used. Fermentative growth on pyruvate, malate, and fumarate. Mesophilic, with optimal growth at 42–45°C. The genus currently accommodates one species. Anoxic media containing a reductant (usually sulfide) and NaCl are necessary for growth. Vitamin requirement is not confirmed. Occurs in anoxic sediments of brackish lake or marine environments polluted by petroleum hydrocarbon.

DNA G + C content (mol%)
: 55.4 (LC); 49.81 (genome).

Type species
:
Desulfoplanes formicivorans
Watanabe, Kojima and Fukui 2015, 1906
VP
.
Analysis of dose comparison techniques for patient‐specific quality assurance in radiation therapy
Authors: Yu Liting , Tang Timothy L. S. , Cassim Naasiha , Livingstone Alexander , Cassidy Darren , Kairn Tanya , Crowe Scott B.
Published: October 2019

Purpose

Gamma evaluation is the most commonly used technique for comparison of dose distributions for patient‐specific pretreatment quality assurance in radiation therapy. Alternative dose comparison techniques have been developed but not widely implemented. This study aimed to compare and evaluate the performance of several previously published alternatives to the gamma evaluation technique, by systematically evaluating a large number of patient‐specific quality assurance results.

Methods

The agreement indices (or pass rates) for global and local gamma evaluation, maximum allowed dose difference (MADD) and divide and conquer (D&C) techniques were calculated using a selection of acceptance criteria for 429 patient‐specific pretreatment quality assurance measurements. Regression analysis was used to quantify the similarity of behavior of each technique, to determine whether possible variations in sensitivity might be present.

Results

The results demonstrated that the behavior of D&C gamma analysis and MADD box analysis differs from any other dose comparison techniques, whereas MADD gamma analysis exhibits similar performance to the standard global gamma analysis. Local gamma analysis had the least variation in behavior with criteria selection. Agreement indices calculated for 2%/2 mm and 2%/3 mm, and 3%/2 mm and 3%/3 mm were correlated for most comparison techniques.

Conclusion

Radiation oncology treatment centers looking to compare between different dose comparison techniques, criteria or lower dose thresholds may apply the results of this study to estimate the expected change in calculated agreement indices and possible variation in sensitivity to delivery dose errors.
Hybrid 3D Printing of Synthetic and Cell‐Laden Bioinks for Shape Retaining Soft Tissue Grafts
Authors: Van Belleghem Sarah , Torres Leopoldo , Santoro Marco , Mahadik Bhushan , Wolfand Arley , Kofinas Peter , Fisher John P.
Published: October 2019

Despite recent advances in clinical procedures, the repair of soft tissue remains a reconstructive challenge. Current technologies such as synthetic implants and dermal flap autografting result in inefficient shape retention and unpredictable aesthetic outcomes. 3D printing, however, can be leveraged to produce superior soft tissue grafts that allow enhanced host integration and volume retention. Here, a novel dual bioink 3D printing strategy is presented that utilizes synthetic and natural materials to create stable, biomimetic soft tissue constructs. A double network ink composed of covalently cross‐linked poly(ethylene) glycol and ionically cross‐linked alginate acts as a physical support network that promotes cell growth and enables long‐term graft shape retention. This is coupled with a cell‐laden, biodegradable gelatin methacrylate bioink in a hybrid printing technique, and the composite scaffolds are evaluated in their mechanical properties, shape retention, and cytotoxicity. Additionally, a new shape analysis technique utilizing CloudCompare software is developed that expands the available toolbox for assessing scaffold aesthetic properties. With this dynamic 3D bioprinting strategy, complex geometries with robust internal structures can be easily modulated by varying the print ratio of nondegradable to sacrificial strands. The versatility of this hybrid printing fabrication platform can inspire the design of future multimaterial regenerative implants.
Freeze‐Facilitated Ligand Binding to Plasmonic Gold Nanorods
Authors: Ye Yang , Liu Zhenchao , Zhang Wenyao , Cheng Xiaoyu , He Sailing
Published: October 2019

Gold nanorods (AuNRs) are an important class of advanced plasmonic materials, but unlike gold nanospheres (AuNSs) their surface modification is difficult due to the specific surfactant layer of cetyltrimethylammonium bromide (CTAB) resulted from the synthesis. In this paper, a freeze‐induced surface modification strategy is proposed for AuNRs. Freezing AuNRs right after a simple wash step can facilitate binding of surface ligands and allow assembly of functional biointerface in a fast time scale. This strategy is simple, fast, versatile, and robust, allowing attachments of different ligand molecules, including organic dyes, poly(ethylene glycol)s (PEGs), and DNAs onto AuNRs without additional reagent. An optimal condition for DNA loading is determined with a matrix driven approach. It is shown that the attached ligand molecules are functional, allowing formation of core–satellite type structures using DNAs linking to AuNSs, or high‐density vertical superlattice arrays using PEGylated AuNRs.
Thiosulfonates as Emerging Reactants: Synthesis and Applications
Authors: Mampuys P. , McElroy C. R. , Clark J. H. , Orru R. V. A. , Maes B. U. W.
Published: October 2019

The synthetic strategies towards thiosulfonates (RSO2SR1) are comprehensively reviewed from their original discovery to recent advances. Incorporation of the green credentials of the synthetic procedures towards thiosulfonates allows one to judge the merits of the state of the art, beyond the typical yield of a product and availability of the reactants. As reactant for organic transformations, thiosulfonates are particularly interesting given their possibility to react with nucleophiles, electrophiles and radicals. This review aims to give researchers, not familiar with the field, a good understanding of the general applications of thiosulfonates, while not skipping the recent important advances. The related, but less explored, selenosulfonates (RSO2SeR1) are also covered.

magnified image
Clinically Approved MRI Contrast Agents as Imaging Labels for a Porous Iron‐Based MOF Nanocarrier: A Systematic Investigation in a Clinical MRI Setting
Authors: Böll Konstantin , Zimpel Andreas , Dietrich Olaf , Wuttke Stefan , Peller Michael
Published: October 2019

Metal‐organic framework nanoparticles (MOF NPs) are a promising class of NP systems that offer versatile and tunable properties. Creating a magnetic resonance imaging (MRI)‐MOF NP platform as a basis for a theranostic drug delivery system is considered an auspicious approach, as MRI is a routinely used clinical method allowing real‐time imaging. So far clinically approved MRI contrast agents (CAs) have not been investigated systematically for the visualization of loading and release from MOF NPs. Here, loading and release of six clinically approved CAs from the MOF MIL‐100(Fe) are investigated in a clinical MRI setting. Standard procedures, beginning with sample preparation up to MRI methods, are established for that purpose. Results are reproduced and verified by Inductively Coupled Plasma Atomic Emission Spectrometry (ICP‐AES) and thiocyanate testing. The macrocyclic CA gadoterate meglumine is identified as the best CA candidate for labeling MIL‐100(Fe). The CA is successfully loaded after 1 h, and also effectively released within the first hour. The MR‐active CA and iron residuals in supernatants are differentiable based on MRI only and concentrations can be successfully calculated. The presented systematic approach suggests procedures and MRI‐methodology that can be used as blueprint strategy when labeling porous NPs with clinically approved MRI CAs.
On flow regime transition in trickle bed: Development of a novel deep‐learning‐assisted image analysis method
Authors: Wang Chao , Li Shaoshuo , Yang Yao , Huang Zhengliang , Sun Jingyuan , Wang Jingdai , Yang Yongrong , Liao Zuwei , Jiang Binbo
Published: October 2019

An image analysis method was developed based on deep‐learning algorithms to extract phase fractions quantitatively in a rectangular trickle bed, and the average identification error was lower than 5%. Furthermore, the flow regime transition in the trickle bed was studied. In trickle‐to‐pulse flow transition, the trickle flow could be further classified into the stable trickle flow and accelerated one. The SD of liquid fractions and the peak width at half‐height of the probability density curve of liquid fractions were close to zero in stable trickle flow, increased rapidly in accelerated trickle flow, and remained approximately constant in pulse flow. In bubble‐to‐pulse flow transition, dispersed bubbles in bubble flow induced the outliers outside the upper boundary of the boxplot of gas fraction, while alternative appearance of gas‐rich zone and liquid‐rich zone in pulse flow induced outliers outside both the upper and lower boundaries of the boxplot of gas fraction.
Modeling the influence of changes in aliphatic structure on char surface area during coal pyrolysis
Authors: Yang He , Fletcher Thomas H. , Li Yang , Jin Lijun , Li Sufen , Shang Yan , Hu Haoquan
Published: October 2019

The influence of changes in aliphatic structure on char surface area during coal pyrolysis was modeled, and the effect was introduced to a previous char surface area model for lignite pyrolysis established based on the chemical percolation devolatilization (CPD) model. The modified model can predict not only the N2 and CO2 char surface area during rapid pyrolysis of three lignites but also the CO2 char surface area of two high‐volatile bituminous coals; the agreement of the modified model with experiments is improved at high temperatures. The decrease in aliphatic chain length can reduce adsorption positions around aromatic core, and decrease char surface area. When mass release is more than 55% at about 1,100 K, the predicted N2 char surface area starts to decrease with further generation of volatiles, and the increase of predicted CO2 char surface area with increasing generation of volatiles also become slow at the end of mass release.
Hematopoietic score predicts outcomes in newly diagnosed multiple myeloma patients
Authors: Al Saleh Abdullah S. , Sidiqi M. Hasib , Dispenzieri Angela , Kapoor Prashant , Muchtar Eli , Buadi Francis K. , Warsame Rahma , Lacy Martha Q. , Dingli David , Leung Nelson , Gonsalves Wilson I. , Kourelis Taxiarchis V. , Gertz Morie A. , Go Ronald S. , Kyle Robert A. , Rajkumar S. Vincent , Kumar Shaji K.
Published: October 2019

Risk stratification of multiple myeloma (MM) at diagnosis is critical. We examined the ability of hematopoietic indices including mean corpuscular volume (MCV), hemoglobin (Hgb), and platelet (Plt) to predict outcomes. This was a retrospective study of patients treated at Mayo Clinic between January 2004 and April 2018. We incorporated three variables (Hgb < 10 g/dL, Plt < 150 × 109/L, and MCV > 96 fL), assigning a score of 1 to each. We identified 1540 newly diagnosed MM patients, of whom 707 (46%) had a score of 0, 513 (33%) had a score of 1, 260 (17%) had a score of 2, and 60 (4%) had a score of 3. The score risk stratified patients into four groups with differing survivals. The median PFS was 32.3 months for score 0, 24.8 months for score 1, 21.7 months for score 2, and 18.3 months for score 3, for P < .001. The median OS was 80.7 months for score 0, 59.9 months for score 1, 51.7 months for score 2, and 31.3 months for score 3, P < .0001. Predictors of OS on the multivariable analysis were age ≥ 65 (HR, 1.93; P < .0001), R‐ISS stage (1‐2 vs 3) (HR, 0.48; P < .0001), and hematopoietic score (0‐2 vs 3) (HR, 0.51; P = .006). A hematopoietic score can predict survival in newly diagnosed myeloma patients.
Transition‐Metal‐Free C2‐H Sulfonylation of Quinoline N‐Oxides via Insertion of Sulfur Dioxide
Authors: Cai Heng , Yang Huiyong , Xu Jun , Bao Hanyang , Huang Lin , Zhang Hongdou , Zhang Pengfei , Li Wanmei
Published: October 2019

Herein, a facile approach for C−H sulfonylation of quinoline N‐oxides via insertion of sulfur dioxide is described. In this method, 2‐sulfonylquinolines with various functional groups can be obtained in good yields under mild reaction conditions. Control experiments indicate that a radical pathway is involved in the C−H sulfonylation.
Mapping holmes tremor circuit using the human brain connectome
Authors: Joutsa Juho , Shih Ludy C. , Fox Michael D.
Published: October 2019

Objective

Holmes tremor is a debilitating movement disorder with limited treatment options. Lesions causing Holmes tremor can occur in multiple different brain locations, leaving the neuroanatomical substrate unclear. Here, we test whether lesion locations that cause Holmes tremor map to a connected brain circuit and whether this circuit might serve as a useful therapeutic target.

Methods

Case reports of Holmes tremor caused by focal brain lesions were identified through a systematic literature search. Connectivity between each lesion location and the rest of the brain was computed using resting state functional connectivity magnetic resonance imaging data from 1,000 healthy volunteers. Commonalities across lesion locations were identified. This Holmes tremor circuit was then compared to neurosurgical treatment targets and clinical efficacy.

Results

We identified 36 lesions causing Holmes tremor, which were scattered across multiple different brain regions. However, all lesion locations were connected to a common brain circuit with nodes in the red nucleus, thalamus, globus pallidus, and cerebellum. In cases with effective neurosurgical treatment, the treatment target was connected with the lesion location, indicating that a second hit to the same circuit might be beneficial. Commonly used deep brain stimulation targets such as the ventral intermediate nucleus and subthalamic nucleus fell outside our Holmes tremor circuit, whereas the globus pallidus target was close, consistent with published clinical response rates for these targets.

Interpretation

Lesions causing Holmes tremor are part of a single connected brain circuit that may serve as an improved therapeutic target. ANN NEUROL 2019;86:812–820
Hydrophobic‐associated polymer‐based laponite nanolayered silicate composite as filtrate reducer for water‐based drilling fluid at high temperature
Authors: Shen Haokun , Lv Kaihe , Huang Xianbin , Liu Jingping , Bai Yingrui , Wang Jintang , Sun Jinsheng
Published: October 2019

Wellbore instability caused by water invasion is the main problem in oil and gas drilling operation. This study reports the utilization of a hydrophobic‐associated polymer‐based laponite nanolayered silicate composite as a filtrate reducer in water‐based drilling fluids (WDFs). The thermal performance and micromorphology of the composite were analyzed by thermogravimetric analysis, transmission electron microscope, and field emission scanning electron microscopy. The results indicated that the composite possessed a “bean pod” structure and a good thermal stability. The rheological properties of the composite solution were evaluated. The results showed that the hydrophobic association interaction of the composite is weak but existent, and the crosslink network structure is variable. The applied performances of WDFs containing the composite were also evaluated. Evaluation results showed that the composite could improve the properties of the thermal stability, salt tolerance, and fluid loss control of WDFs. The particle size distribution of WDFs and the micrographs of filter cakes explained the improving. The composite was expected to be applied as an efficient filtrate reducer for developing high performance drilling fluids. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48608.
Multiple Active Sites: Lithium Storage Mechanism of Cu‐TCNQ as an Anode Material for Lithium‐Ion Batteries
Authors: Meng Chunfeng , Chen Tianhui , Fang Chun , Huang Yunhui , Hu Pinfei , Tong Yongli , Bian Ting , Zhang Jiaojiao , Wang Zhaoxuan , Yuan Aihua
Published: October 2019

Recently, carboxylate metal‐organic framework (MOF) materials were reported to perform well as anode materials for lithium‐ion batteries (LIBs); however, the presumed lithium storage mechanism of MOFs is controversial. To gain insight into the mechanism of MOFs as anode materials for LIBs, a self‐supported Cu‐TCNQ (TCNQ: 7,7,8,8‐tetracyanoquinodimethane) film was fabricated via an in situ redox routine, and directly used as electrode for LIBs. The first discharge and charge specific capacities of the self‐supported Cu‐TCNQ electrode are 373.4 and 219.4 mAh g−1, respectively. After 500 cycles, the reversible specific capacity of Cu‐TCNQ reaches 280.9 mAh g−1 at a current density of 100 mA g−1. Mutually validated data reveal that the high capacity is ascribed to the multiple‐electron redox conversion of both metal ions and ligands, as well as the reversible insertion and desertion of Li+ ions into the benzene rings of ligands. This work raises the expectation for MOFs as electrode materials of LIBs by utilizing multiple active sites and provides new clues for designing improved electrode materials for LIBs.
Reverberation mapping of distant quasars: Time lag determination using different methods
Authors: Zajaček Michal , Czerny B. , Martínez‐Aldama Mary Loli , Karas Vladimir
Published: October 2019

By applying different statistically robust methods, we analyze the time lag between the continuum and ionized line‐emission (Mg II line) light curves for the distant bright quasar CTS C30.10 (redshift z∼0.9). The data were obtained by the 10‐meter South African Large Telescope (SALT) telescope in South Africa. In detail, we demonstrate the application of several methods using the interpolated cross‐correlation function (ICCF), discrete correlation function (DCF), z‐transformed discrete correlation function (zDCF), von Neumann estimator, and the JAVELIN code package. In particular, we discuss the uncertainties of these methods. In conclusion, we find that the quasar lies on the broad‐line region (BLR) size—monochromatic luminosity power‐law scaling, , which was already confirmed for low‐redshift sources. In case, the BLR size–luminosity relation holds for other distant sources, quasars could be used to probe cosmological models as “standard candles” complementary to supernovae Ia.
Isodensity analysis of comets using the collection of digitized Engelhardt Astronomical Observatory photographic plates
Authors: Nefedyev Yury , Andreev Alexey , Hudec Rene
Published: October 2019

The field of astronomy dealing with comets is an important component of modern space investigations. This applies both to the study of physical, chemical, and evolutionary parameters and to the determination of connections between meteor showers and their parental bodies. This paper considers the isodensity analysis of Arend‐Roland, 45P/Honda, and Bennett comets using the measurements of photographic plates performed at Engelhardt Astronomical Observatory. On the basis of a software aimed at analyzing the brightness of digital images, structural models for three comets were developed. The isophotes of their nuclei, comas, and tails were determined as well. As the cometary nuclei are the elements of dynamical evolution and processes in the Solar Nebula, the study of a digital database on comets will allow refining the theory of their formation and evolution.