bluuebunny/crossref_metadata_2025 huggingface dataset:
Central distribution of oxytocin and vasopressin 1a receptors in juvenile Richardson’s ground squirrels
Authors: Freeman Angela R. , Hare James F. , Caldwell Heather K.
Published: February 2019

Oxytocin and vasopressin are well‐conserved peptides important to the regulation of numerous aspects of social behavior, including sociality. Research exploring the distribution of the receptors for oxytocin (Oxtr) and for vasopressin (Avpr1a) in mammals has revealed associations between receptor distribution, sociality, and species’ mating systems. Given that sociality and gregariousness can be tightly linked to reproduction, these nonapeptides unsurprisingly support affiliative behaviors that are important for mating and offspring care. We localized these receptors in juvenile Richardson’s ground squirrel brains to determine whether distribution patterns of Oxtr and Avpr1a that are associated with promiscuous mating systems differ in rodents that also exhibit non‐reproductive affiliation. These squirrels are social, colonial, and engage in nepotistic alarm calling behavior and affiliation outside of a reproductive context. Juveniles are the most affiliative age‐class and are non‐reproductive; making them ideal for examining these associations. We found that juveniles had dense Oxtr binding in the dentate gyrus of the hippocampus, amygdala, lateral septum, bed nucleus of the stria terminalis and medial geniculate nucleus. Juveniles had low to modest levels of Avpr1a binding in the medial preoptic area, olfactory bulbs, nucleus accumbens, superior colliculus, and inferior colliculus. We noted Oxtr and Avpr1a binding in the social behavior neural network (SBNN), further supporting a role of these nonapeptides in modulating social behavior across taxa. Oxtr and Avpr1a binding was also present in brain regions important to auditory processing that have known projections to the SBNN. We speculate that these neural substrates may be where these nonapeptides regulate communication.
Identification of two two‐component signal transduction mutants with enhanced sucrose biosynthesis in Synechococcus elongatus PCC 7942
Authors: Qiao Cuncun , Zhang Mingyi , Luo Quan , Lu Xuefeng
Published: February 2019

Metabolic engineering of the freshwater cyanobacterium Synechococcus elongatus PCC 7942 (Syn7942), synthesizing sucrose as the only compatible solute upon salt stress, has greatly improved its sucrose productivity. However, the signaling and regulatory mechanisms of this physiological process are still unknown. To know more about these aspects, a library of inactivation mutants for all 44 predicted signal transduction genes of Syn7942 was constructed. By evaluating sucrose production, two two‐component signal transduction mutants Δ1125 and Δ1404, in which Synpcc7942_1125 and Synpcc7942_1404 was inactivated, respectively, were identified. They exhibited stably enhanced sucrose production, but the growth and the expression of sps encoding sucrose‐phosphate synthase under salt stress were not affected, indicating that the corresponding signal transduction proteins do not regulate salt‐induced sucrose synthesis by directly regulating sps expression. Moreover, the glycogen accumulation was enhanced in Δ1125 and Δ1404, and the salt stress‐intensified photodamage of these mutants was also found to be relieved. These results indicated that the basic cell metabolisms such as glycogen metabolism and photosynthesis of the mutants were affected by gene inactivation, which might further affect salt‐induced sucrose synthesis. Further studies on gene functions and signaling pathways or networks of Synpcc7942_1125 and Synpcc7942_1404 would reveal more details about the molecular bases for the observed phenotypes of Δ1125 and Δ1404.
Cold spells in Poland and Germany and their circulation conditions
Authors: Tomczyk Arkadiusz M. , Bednorz Ewa , Sulikowska Agnieszka
Published: February 2019

The primary objective of this paper was to determine the circulation conditions of the occurrence of cold spells in Poland and Germany. The observed inconsiderable warming slightly contributed to a change in the number of cold days and cold spells. The occurrence of cold spells in Poland and Germany was related to considerably more active and intensive pressure systems than on average in the winter season in the studied years. A strong high pressure system was located over much of the continent, blocking westerly circulation. During the occurrence of cold spells, negative anomalies of isobaric surface heights were recorded with the greatest anomalies being in the 300–250 hPa heights. The highest air temperature anomalies were recorded on the lowest isobaric levels, where they amounted to <−10°C. On average, anomalies on the 300 hPa isobaric level began developing approximately 9 days before the beginning of cold spells over the study area. The decay of cold spells was not related to rapid exchange of air masses, but rather to gradual weakening of anomalies in the upper troposphere, and their shifting westwards.
High‐fat diet aggravates the liver disease caused by periodontitis in rats
Authors: Andrade Raissa Silva Bacelar de , França Luiz Felipe de Carvalho , Pessoa Larissa dos Santos , Landim Bruno de Almeida Arrais , Rodrigues Ayane Araújo , Alves Even Herlany Pereira , Lenardo David Di , Nascimento Hélio Mateus Silva , Sousa Francisca Beatriz de Melo , Barbosa André Luiz dos Reis , Medeiros Jand‐Venes Rolim , Vasconcelos Any Carolina Cardoso Guimarães , Vasconcelos Daniel Fernando Pereira
Published: February 2019

Background

Periodontitis is an inflammatory disease that causes periodontium and hepatic alterations. Liver disease is related to the intake of foods rich in fat and sugars (high‐fat). The objective of this study was to evaluate whether a high‐fat diet can aggravate the liver disease caused by ligature‐induced periodontitis in rats.

Methods

Twenty‐one female rats were divided into three groups (n = 7 in each group): control; periodontitis (periodontitis induced with ligature) and high‐fat + periodontitis (received hypercaloric diet and induction of periodontitis). The rats were submitted to the analyses of the following periodontal parameters: gingival bleeding index (GBI), probing pocket depth (PPD), tooth mobility (TM), and alveolar bone height. In the hepatic tissue, the levels of malondialdehyde (MDA), glutathione (GSH), total cholesterol, and myeloperoxidase activity (MPO) were measured. Liver samples were also histopathologically evaluated. Finally, blood levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), glucose, total cholesterol, cholesterol high‐density lipoprotein (HDL), and uric acid were measured.

Results

The high‐fat + periodontitis group presented an increase in the steatosis score (P < 0.05) for the histopathologic evaluation, when compared with the periodontitis group. MDA, uric acid and ALT levels also increased, whereas GSH and HDL levels showed lower values.

Conclusion

A high‐fat diet aggravates the liver disease caused by ligature‐induced periodontitis in rats.
Developing nitrogen management strategies under drip fertigation for wheat and maize production in the North China Plain based on a 3‐year field experiment
Authors: Li Haoru , Hao Weiping , Liu Qi , Mao Lili , Nangia Vinay , Guo Rui , Mei Xurong
Published: February 2019

The intensive winter wheat (Triticum aestivum L.)–summer maize (Zea mays L.) cropping systems in the North China Plain (NCP) rely on the heavy use of mineral nitrogen (N) fertilizers. As the fertigated area of wheat and maize in the NCP has grown rapidly during recent years, developing N management strategies is required for sustainable wheat and maize production. Field experiments were conducted in Hebei Province during three consecutive growth seasons in 2012–2015 to assess the influence of different N fertigation rates on N uptake, yield, and nitrogen use efficiency [NUE: recovery efficiency (REN) and agronomic efficiency (AEN)]. Five levels of N application, 0 (FN0), 40 (FN40%), 70 (FN70%), 100 (FN100%), and 130% (FN130%) of the farmer practice rate (FP: 250 kg N ha−1 and 205.5 kg N ha−1 for wheat and maize, respectively), corresponding to 0, 182.2, 318.9, 455.5, and 592.2 kg N ha−1 y−1, respectively, were tested. Nitrogen in the form of urea was dissolved in irrigation water and split into six and four applications for wheat and maize, respectively. In addition, the treatment “drip irrigation + 100% N conventional broadcasting” (DN100%) was also conducted. All treatments were arranged in a randomized complete block design with three replications. The results revealed the significant influence of both N fertigation rate and N application method on grain yield and NUE. Compared to DN100%, FN100% significantly increased the 3‐year averaged N recovery efficiency (REN) by 0.09 kg kg−1 and 0.04 kg kg−1, and the 3‐year averaged N agronomic efficiency (AEN) by 2.43 kg kg−1 and 1.62 kg kg−1 for wheat and maize, respectively. Among N fertigation rates, there was no significant increase in grain yield in response to N applied at a greater rate than 70% of FP due to excess N accumulation in vegetative tissues. Compared to FN70%, FN100%, and FN130%, FN40% increased the REN by 0.17–0.57 kg kg−1 and 0.03–0.34 kg kg−1and the AEN by 4.60–27.56 kg kg−1 and 2.40–10.62 kg kg−1 for wheat and maize, respectively. Based on a linear‐response relationship between the N fertigation rate and grain yield over three rotational periods it can be concluded that recommended N rates under drip fertigation with optimum split applications can be reduced to 46% (114.6 kg N ha−1) and 58% (116.6 kg N ha−1) of FP for wheat and maize, respectively, without negatively affecting grain yield, thereby increasing NUE.
Brassica meal‐derived allyl‐isothiocyanate postharvest application: influence on strawberry nutraceutical and biochemical parameters
Authors: Ugolini Luisa , Pagnotta Eleonora , Matteo Roberto , Malaguti Lorena , Di Francesco Alessandra , Lazzeri Luca
Published: February 2019

BACKGROUND

The antimicrobial activity of allyl‐isothiocyanate (AITC) on plant pathogens is well known and has already been demonstrated in the strawberry with respect to Botritis cinerea fungal infection using postharvest biofumigation. In the present study, vapours of 0.08 mg L−1 of Brassica meal‐derived AITC were applied to strawberry to assess its effect on fruit nutraceutical and biochemical parameters after 2 days of storage at 20 °C and 90% relative humidity.

RESULTS

Allyl‐isothiocyanate showed no detrimental effect on final strawberry quality, anti‐oxidant properties or ascorbic acid content. By contrast, an increased amount of asparagine and a higher ascorbate and glutathione redox potential were registered in the fruit soon after treatment. A reversible glutathione depletion action of AITC was also observed. Finally, total AITC residues in treated strawberry were quantified and a relatively high amount of AITC‐adducts was found in fruit tissues.

CONCLUSION

The findings of the present study not only confirm the high potentiality of biofumigation with respect to extending the shelf‐life of fruit, but also provide some insight regarding the mechanisms of action of AITC at the cellular level as a possible elicitor of fruit protective responses. Nevertheless, the nature of the AITC‐adducts formed in fruit tissues needs further attention to enable a health and safety assessment of the final fruit. © 2019 Society of Chemical Industry
Green synthesis of silver nanoparticles using tomato leaf extract and their entrapment in chitosan nanoparticles to control bacterial wilt
Authors: Santiago Thaís R , Bonatto Cínthia C , Rossato Maurício , Lopes Cláudio A P , Lopes Carlos A , G Mizubuti Eduardo S , Silva Luciano P
Published: February 2019

BACKGROUND

Silver nanoparticles (AgNPs), particularly those entrapped in polymeric nanosystems, have arisen as options for managing plant bacterial diseases. Among the biopolymers useful for the entrapment of AgNPs, chitosan is promising because of its low cost, good biocompatibility, antimicrobial properties and biodegradability. The present study aimed: (i) to greenly‐synthesize AgNPs using different concentrations of aqueous extract of tomato leaves followed by entrapment of AgNPs with chitosan (CH‐AgNPs); (ii) to characterize the optical, structural and biological properties of the nanosystems produced; (iii) to evaluate the antimicrobial activities of AgNPs and nanomaterials; and (iv) to assess the effectiveness of AgNPs and nanomaterials for controlling tomato bacterial wilt caused byRalstonia solanacearum.

RESULTS

Spherical and oval AgNPs had incipient colloidal instability, although the concentration of the tomato leaf extract influenced both size (< 87 nm) and the polydispersity index. Nanomaterials (< 271 nm in size) were characterized by a highly stable matrix of chitosan containing polydisperse AgNPs. Free AgNPs and CH‐AgNPs were stable for up to 30 days, with no significant alteration in physicochemical parameters. The AgNPs and nanomaterials had antibacterial activity and decreased bacterial growth at micromolar concentrations after 48 h. Morphological changes inR. solanacearumcells were observed after treatment with CH‐AgNPs. The application of CH‐AgNPs at 256 µmol L−1reduced the incidence of bacterial wilt in a partially resistant tomato genotype but not in the susceptible line.

CONCLUSION

Greenly‐synthesized chitosan‐derived nanomaterials containing AgNPs produced with leaf extracts from their own species appear to comprise a promising and sustainable alternative in an integrated management approach aiming to reduce the yield losses caused by bacterial wilt. © 2019 Society of Chemical Industry
Cross‐border infrastructural development and residents' perceived tourism impacts: A case of China–Pakistan Economic Corridor
Authors: Nazneen Shama , Xu Hong , Din Nizam Ud
Published: February 2019

Drawing on social exchange theory, Butler's tourism area life cycle model, and previous literature, this study empirically tests direct and indirect relationships among perceived impacts of China–Pakistan Economic Corridor (CPEC) infrastructural development, perceived tourism impacts, and support for tourism development. Using a sample of 800 questionnaires in structural equation modeling, the tested model explores that perceived impacts of CPEC infrastructural development as an antecedent, directly and indirectly influences residents' support for tourism development. However, contrary to our predictions, the study finding indicates a positive relationship between perceived tourism costs and support for tourism development. This relationship addressed that residents are more likely to support tourism even if tourism costs outweigh the benefits.
Sonolocation during submandibular sialolithotomy
Authors: Romero Nahir J. , Fuson Andrew , Kieliszak Christopher R. , Joshi Arjun S.
Published: February 2019

Objectives/Hypothesis

Ultrasound is a proven tool for diagnostic and therapeutic purposes for treatment of salivary gland pathology. It is also useful for localization of calculi during submandibular gland transoral sialolithotomy when calculi cannot easily be palpated. Our objective was to determine the efficacy of sialolith localization using ultrasound during submandibular gland sialolithotomy.

Study Design

Retrospective case series.

Methods

A study performed utilizing data compiled from 2009 through 2016 in a tertiary academic center. Treatment was completed in 164 patients with sialadenitis and sialolithiasis by submandibular gland transoral sialolithotomy in either the office (81%) or the operating room (19%). Ultrasound was used for localization of sialoliths during submandibular gland sialolithotomy. Main treatment outcomes studied were success of the procedure, complications, and follow‐up.

Results

Successful sialolithotomy was performed in (147 patients) 90% of cases. Complications were minimal and included stricture formation, which occurred in 3% (five patients) of cases, followed by ranula formation in 1.8% (three patients) of cases. There were no incidences of lingual nerve injury.

Conclusions

Ultrasound can be used effectively for precise sialolith localization intraoperatively.

Level of Evidence

4

Laryngoscope, 129:2716–2720, 2019
Survival under conditions of variable food availability: Resource utilization and storage in the cold‐water coral Lophelia pertusa
Authors: Maier Sandra R. , Kutti Tina , Bannister Raymond John , van Breugel Peter , van Rijswijk Pieter , van Oevelen Dick
Published: February 2019

Cold‐water coral (CWC) reefs are hotspots of biodiversity and productivity in the deep sea, but their distribution is limited by the availability of food, which undergoes complex local and temporal variability. We studied the resource utilization, metabolism, and tissue storage of CWC Lophelia pertusa during an experimentally simulated 3‐day food pulse, of 13C15N‐enriched phytodetritus, followed by a 4‐week food deprivation. Oxygen consumption (0.145 μmol O2 [mmol organic carbon {OC}]−1 h−1), release of particulate organic matter (0.029 μmol particulate organic carbon [POC] [mmol OC]−1 h−1 and 0.005 μmol particulate organic nitrogen [mmol OC]−1 h−1), ammonium excretion (0.004 μmol NH4+ [mmol OC]−1 h−1), tissue C and N content, and fatty acid (FA) and amino acid composition did not change significantly during the experiment. Metabolization of the labeled phytodetritus, however, underwent distinct temporal dynamics. Initially, L. pertusa preferentially used phytodetritus‐derived C for respiration (2.2 ± 0.36 nmol C [mmol OC]−1 h−1) and mucus production (0.94 ± 0.52 nmol C [mmol OC]−1 h−1), but those tracer fluxes declined exponentially to <20% within 2 weeks after feeding and then remained stable, indicating that the remainder of the incorporated phytodetritus had entered a tissue pool with lower turnover. Analysis of 13C in individual FAs revealed a mismatch between the FAs incorporated from phytodetritus and the FA requirements of the coral. We suggest that feeding on other resources, such as lipid‐rich zooplankton, could fill this deficiency. A release of 10% of their total OC as respired C and POC during the 4‐week food deprivation underlines the importance of regular food pulses for CWC reefs.
Environmental drivers of mixotrophs in boreal lakes
Authors: Hansson Truls Hveem , Grossart Hans‐Peter , del Giorgio Paul A. , St‐Gelais Nicolas F. , Beisner Beatrix E.
Published: February 2019

Mixotrophy is increasingly recognized as an important trophic pathway among phytoplankton, yet its underlying drivers remain largely unknown and unexplored. Here, we present a study utilizing 69 lake samplings in boreal Quebec, Canada, identifying variables driving the success of phytoplankton that have a capacity for mixotrophy and pointing to the underlying mechanisms. We found that the success of mixotrophs (% of total biomass) was positively influenced by both colored dissolved organic matter (cDOM) and dissolved CO2 concentration but limited by the abundance of crustacean zooplankton. The effect of cDOM manifested as a consequence of limited autotrophic phytoplankton biomass in lakes with reduced light penetration. We observed a nonlinear (u‐shaped) relation between CO2 and mixotrophs, with biomass favored at both low and high CO2 concentrations. A reduced fitness of mixotrophs at near‐atmospheric CO2 concentrations is likely owing to the costs of rapidly switching between or maintaining multiple trophic strategies. The abundance of zooplankton had a negative effect on mixotroph biomass but a positive effect on autotrophic phytoplankton. We also found that while the community composition of potentially mixotrophic phytoplankton was to some degree likely influenced by zooplankton biomass, composition was unaffected by the CO2 and cDOM gradients. Overall, this study highlights mixotrophy in boreal lake systems as a strategy of persistence, with the maintenance of a moderate but constant presence across a changing gradient of light and trophic conditions. The results of our study support the hypothesis that phytoplankton with a capacity for mixotrophy provide a superior and stable stoichiometric food source for zooplankton, implicating mixotrophs as a vital component of boreal lake food webs.
Phylogenetic signature of light and thermal stress for the endosymbiotic dinoflagellates of corals (Family Symbiodiniaceae)
Authors: Lesser Michael P.
Published: February 2019

Coral reefs around the world have been affected by a climate‐change induced phenomenon known as “coral bleaching,” which is caused by the interaction between high irradiance and elevated seawater temperatures, and involves the mass expulsion of Symbiodiniaceae from anemones, sponges, and corals. The primary drivers of this phenomenon are the inherent genetic variability in the Family Symbiodiniaceae, and the variability in the abiotic environment for variables such as irradiance and temperature. Recent experiments have either disregarded the important interactive role of irradiance or have suggested that photooxidative stress is not a prerequisite for coral bleaching because certain reactive oxygen species (ROS) can be produced in the dark. Here, fluorescent probes are used as proxies for the relative concentration of ROS in different genera of cultured Symbiodiniaceae under varying thermal and light conditions. The results show that taxon‐specific patterns of the concentration of ROS are observed but that all genera tested produced significantly greater amounts of superoxide radicals and hydrogen peroxide, compared to singlet oxygen, when exposed to high light and thermal stress. These results are contextualized in relation to the primary drivers of ROS production and the photo‐physiological basis for differences in ROS production that may then be correlated with symbiont driven coral bleaching.
Ultra‐Broadband and Ultra‐Compact On‐Chip Silicon Polarization Beam Splitter by Using Hetero‐Anisotropic Metamaterials
Authors: Xu Hongnan , Dai Daoxin , Shi Yaocheng
Published: February 2019

The polarization beam splitter (PBS) is an essential component in the polarization diversity circuit to overcome the strong polarization dependence of silicon nanophotonic devices. Among various PBS structures, the asymmetrical directional couplers (ADCs) are most commonly used due to the best overall performances. However, it is still challenging to realize an on‐chip silicon PBS with a small footprint, low loss, high extinction ratio, and, especially, broad bandwidth, simultaneously. The working bandwidth is limited for ADCs, since the wavelength difference will introduce deviations to both the effective indices and the coupling strength, which would distort the phase‐matching property and the optimal coupling length. In this paper, an on‐chip silicon PBS is proposed and demonstrated using “effective medium anisotropy” instead of “configuration asymmetry” to break the bandwidth bottleneck. The metamaterials with engineered anisotropy and dispersion are utilized to form a hetero‐anisotropic slab. For TM polarization, the slab performs as a multi‐mode interference coupler, while for TE polarization, the slab performs as two isolated waveguides. The fabricated PBS shows low loss <1 dB, high extinction ratio >20 dB, and a record working bandwidth >200 nm, with a footprint as small as 12.25 × 1.9 µm2.
Clonality and genetic profiles of drug‐resistant Mycobacterium tuberculosis in the Eastern Cape Province, South Africa
Authors: Bhembe Nolwazi L. , Nwodo Uchechukwu U. , Okoh Anthony I. , Obi Chikwelu L. , Mabinya Leonard V. , Green Ezekiel
Published: February 2019

In this study, we investigated the diversity of drug‐resistant Mycobacterium tuberculosis isolates from families who own cattle in the Eastern Cape Province of South Africa using spoligotyping and mycobacterial interspersed repetitive‐unit‐variable number tandem repeat (MIRU‐VNTR) typing. The Mycobacterium tuberculosis was investigated using MIRU‐VNTR and the Mycobacterium tuberculosis families were evaluated using spoligotyping. Spoligotyping grouped 91% of the isolates into seven clusters, while 9% of the deoxyribonucleic acid (DNA) from TB isolates were unclustered from a total of 154 DNA used. Previously described shared types were observed in 89.6% of the isolates, with the Beijing family, SIT1, the principal genotype in the province, while the families T, SIT53 and X1, SIT1329 were the least detected genotypes. MIRU‐VNTR grouped 81% of the isolates in 23 clusters while 19% were unclustered. A combination of the VNTR and spoligotyping grouped 79% of the isolates into 23 clusters with 21% unclustered. The low level of diversity and the clonal spread of drug‐resistant Mycobacterium tuberculosis isolates advocate that the spread of TB in this study may be instigated by the clonal spread of Beijing genotype. The results from this study provide vital information about the lack of TB control and distribution of Mycobacterium tuberculosis complex strain types in the Eastern Cape Province of South Africa.
ESBL‐production in Escherichia coli and Klebsiella pneumoniae isolates from Nigeria
Authors: Hertz Frederik B. , Jansåker Fillip , Okon Kenneth O. , Abdulmumin Ibrahim S. , Onah Joseph O. , Ladan Joshua , Knudsen Jenny D.
Published: February 2019

The worldwide increase in infections caused by extended‐spectrum beta‐lactamase‐ (ESBL) and AmpC‐producing Enterobacteriaceae (ESBL‐E) is a concern. Surveillance is extensive in Europe, North America, and Asia. Yet, there is no summarizing surveillance in Africa. This study aimed to perform a preliminary investigation on the prevalence of ESBL‐E in the northeastern part of Nigeria. However, of the 60 samples collected, we were able to culture 15 Escherichia coli and 7 Klebsiella spp. only. In the collection of clinical hospital samples, we found eight of 15 E. coli isolates to be ESBL (53%) and two out of seven Klebsiella spp. to be ESBL/AmpC (29%). Due to the limitations of this study, our findings cannot take a broad view on the prevalence of ESBL‐E, in Nigeria and other parts of Africa. Yet, to know which genes encode ESBL in Nigeria, and to know exact prevalence of every ESBL gene would be of importance.
1.6‐2.6 GHz continuous Class‐F power amplifier with gain and power‐added efficiency flatness enhancement by negative feedback structure
Authors: Qi Chongchong , Luo Yonglun , Feng Xuxu , Dong Chaoran
Published: February 2019

This article studies the feasibility of applying negative feedback structure in continuous Class‐F power amplifiers to improve the gain and efficiency flatness. The operation principle of the negative feedback structure under small and large signal input states is presented. The gain and efficiency are increased at high frequency part and decreased at low frequency by introducing the negative feedback structure, and the flatness is improved. Multiharmonic bilateral pull is used to obtain the optimum impedances, to reduce the interaction between source and load side, and the influence of parasitic parameters. A highly flatness amplifier with the negative feedback structure is designed operating at 1.6‐2.6 GHz by using a Cree GaN HEMT CGH40010H device. The measurement results show a gain flatness of 1.1 dB, and a power‐added efficiency flatness of 9%.
Low radar cross section microstrip antenna based on left‐handed material
Authors: Zhang Jia Kai , Xu Jia Chen , Ding Jun , Guo Chen Jiang
Published: February 2019

This article designs a hexagonal left‐handed material (LHM) and proposes a microstrip antenna with low radar cross‐section (RCS) based on this new LHM. The modified antenna RCS is significantly reduced without reducing radiation performance compared with two reference antennas. The scattering distribution shows the RCS reduction is attributable to the LHM. Antenna prototypes are fabricated and measured to verify the simulation. As a result, the modified antenna realized RCS reduction while maintaining radiation performance, with 19.5 dB maximum RCS reduction at 1.16 GHz, and the out‐of‐band RCS reduced due to the converged electromagnetic wave caused by the LHM.
Detection of potential microcalcification clusters using multivendor for‐presentation digital mammograms for short‐term breast cancer risk estimation
Authors: Alsheh Ali Maya , Eriksson Mikael , Czene Kamila , Hall Per , Humphreys Keith
Published: February 2019

Purpose

We explore using the number of potential microcalcification clusters detected in for‐presentation mammographic images (the images which are typically accessible to large epidemiological studies) a marker of short‐term breast cancer risk.

Methods

We designed a three‐step algorithm for detecting potential microcalcification clusters in for‐presentation digital mammograms. We studied association with short‐term breast cancer risk using a nested case control design, with a mammography screening cohort as a source population. In total, 373 incident breast cancer cases (diagnosed at least 3 months after a negative screen at study entry) and 1466 matched controls were included in our study. Conditional logistic regression Wald tests were used to test for association with the presence of microcalcifications at study entry. We compared results of these analyses to those obtained using a Computer‐aided Diagnosis (CAD) software (VuComp) on corresponding for‐processing images (images which are used clinically, but typically not saved).

Results

We found a moderate agreement between our measure of potential microcalcification clusters on for‐presentation images and a CAD measure on for‐processing images. Similar evidence of association with short‐term breast cancer risk was found (P = andP = , for our approach on for‐presentation images and for the CAD measure on for‐processing images, respectively) and interestingly both measures contributed independently to association with a short‐term risk (P = for the CAD measure, adjusted for our proposed method andP = for our proposed method, adjusted for the CAD measure).

Conclusion

Meaningful measurement of potential microcalcifications, in the context of short‐term breast cancer risk assessment, is feasible for for‐presentation images across a range of vendors. Our algorithm for for‐presentation images performs similarly to a CAD algorithm on for‐processing images, hence our algorithm can be a useful tool for research on microcalcifications and their role on breast cancer risk, based on large‐scale epidemiological studies with access to for‐presentation images.
Longitudinal fan‐beam computed tomography dataset for head‐and‐neck squamous cell carcinoma patients
Authors: Bejarano Tatiana , De Ornelas‐Couto Mariluz , Mihaylov Ivaylo B.
Published: February 2019

Purpose

To describe in detail a dataset consisting of longitudinal fan‐beam computed tomography (CT) imaging to visualize anatomical changes in head‐and‐neck squamous cell carcinoma (HNSCC) patients throughout radiotherapy (RT) treatment course.

Acquisition and validation methods

This dataset consists of CT images from 31 HNSCC patients who underwent volumetric modulated arc therapy (VMAT). Patients had three CT scans acquired throughout the duration of the radiation treatment course. Pretreatment planning CT scans with a median of 13 days before treatment (range: 2–27), mid‐treatment CT at 22 days after start of treatment (range: 13–38), and post‐treatment CT 65 days after start of treatment (range: 35–192). Patients received RT treatment to a total dose of 58–70 Gy, using daily 2.0–2.20 Gy, fractions for 30–35 fractions. The fan‐beam CT images were acquired using a Siemens 16‐slice CT scanner head protocol with 120 kV and current of 400 mAs. A helical scan with 1 rotation per second was used with a slice thickness of 2 mm and table increment of 1.2 mm. In addition to the imaging data, contours of anatomical structures for RT, demographic, and outcome measurements are provided.

Data format and usage notes

The dataset with DICOM files including images, RTSTRUCT files, and RTDOSE files can be found and publicly accessed in the Cancer Imaging Archive (TCIA, http://www.cancerimagingarchive.net/) as collection Head‐and‐neck squamous cell carcinoma patients with CT taken during pretreatment, mid‐treatment, and post‐treatment (HNSCC‐3DCT‐RT).

Discussion

This is the first dataset to date in TCIA which provides a collection of multiple CT imaging studies (pretreatment, mid‐treatment, and post‐treatment) throughout the treatment course. The dataset can serve a wide array of research projects including (but not limited to): quantitative imaging assessment, investigation on anatomical changes with treatment progress, dosimetry of target volumes and/or normal structures due to anatomical changes occurring during treatment, investigation of RT toxicity, and concurrent chemotherapy and RT effects on head‐and‐neck patients.
An evaluation of kefir grain size with magnetic resonance imaging to observe the fermentation of milk
Authors: Spicer Abi , Fairhurst David J. , Newton Michael I. , Morris Robert H.
Published: February 2019

Kefirian milk is a fermented beverage consumed worldwide. Originally produced in animal skins, it is now prepared both industrially and at home by adding symbiotic cultures of bacteria and yeast known as kefir grains to fresh milk. There is significant literature on the biological aspects of this process but little focus on the fermentation effects on the bulk milk as a function of the grain morphology. Changes in the Magnetic Resonance (MR) signal as measured using a whole body clinical magnetic resonance imaging scanner are found to be proportional to traditional gas measurements with correlation coefficients in excess of 0.95. Magnetic Resonance Imaging is then also used to determine the effect of grain size on the rate of fermentation of milk. It is found that larger grains result in signal intensity changes on the order of 0.03 a.u per hour, but by breaking the grains into pieces around 3mm, the reaction rate can be more than doubled to 0.07 a.u. per hour. It is thought that this shows promise as a method to improve the speed of production of kefirian milk and by arresting the process partway through fermentation, gives control over the properties of the end product.
A numerical and experimental study of RF shimming in the presence of hip prostheses using adaptive SAR at 3 T
Authors: Destruel Aurelien , Fuentes Miguel , Weber Ewald , O’Brien Kieran , Jin Jin , Liu Feng , Barth Markus , Crozier Stuart
Published: February 2019

Purpose

Parallel transmission techniques in MRI have the potential to improve the image quality near metal implants at 3 T. However, current testing of implants only evaluates the risk of radiofrequency (RF) heating in phantoms in circularly polarized mode. We investigate the influence of changing the transmission settings in a 2‐channel body coil on the peak temperature near 2 CoCrMo hip prostheses, using adaptive specific absorption rate (SAR) as an estimate of RF heating.

Methods

Adaptive SAR is a SAR averaging method that is optimized to correlate with thermal simulations and limit the temperature to 39°C near hip implants. The simulated peak temperature was compared when using whole‐body SAR, SAR10g, and adaptive SAR as a constraint for the maximum allowed input power. Adaptive SAR was used as a fast estimate of temperature to evaluate the trade‐off between good image quality and low heating near the hip implants. Electromagnetic simulations were validated by simulating and measuring B1 maps and electric fields in a phantom at 3 T.

Results

Simulations and measurements showed excellent agreement. Limiting whole‐body SAR to 2 W/kg and SAR10g to 10 W/kg resulted in temperatures up to 49.3°C and 40.7°C near the hip implants after 30 minutes of RF exposure, respectively. Predictions based on adaptive SAR limited the temperature to 39°C, and allowed to improve the B1 field distribution while preventing peak temperatures near the hip implants.

Conclusion

Significant RF heating can occur at 3 T near hip implants when parallel transmission is used. Adaptive SAR can be integrated in RF shimming algorithms to improve the uniformity and reduce heating.
Urethral bulking agents for female stress urinary incontinence
Authors: Hussain Sadiya M. , Bray Rhiannon
Published: February 2019

Urethral bulking agents (UBAs) to treat stress urinary incontinence was first described in the 1930s, when paraffin was used to increase urethral resistance. Since then, several agents have been introduced to the market, with varying degrees of safety, efficacy, and durability. The agents currently available include calcium hydroxyl apatite (Coaptite®), carbon coated zirconium (Durasphere®); polydimethylsiloxane elastomer (Macroplastique®); and polyacrylamide hydrogel (Bulkamid®). The latest product, PDMS‐U (Urolastic ®) is a silicone gel that polymerizes when injected. The short term efficacy of UBAs are generally encouraging; however, longer follow up results show the success rates are reduced and many women will require a repeat treatment. This review looks at the currently available UBAs, application techniques, and the clinical data on their safety and efficacy.
Scarce as hen's teeth: Women CEOs in large nonprofit organizations
Authors: Lee Young‐Joo
Published: February 2019

This study examines an underlying mechanism behind the gender gap in nonprofit executive leadership, focusing on the link between the representation of women on governing boards and the hiring of female CEOs. The analysis of 340 human services organizations with gross receipts greater than $10 million in GuideStar's database reveals that organizations where women make up between one third and half of the board are more likely to have a female CEO compared to organizations where women account for less than one third or a majority of the board. The findings suggest that nonprofit organizations are more likely to hire a female CEO when women constitute a “substantial minority” of the governing board.
Surgical and anesthetic management for hepatectomy in two pediatric patients with trisomy 18, pulmonary hypertension, and hepatoblastoma
Authors: Lucas Donald J. , Rubinstein Jeremy , Gosain Ankush , Tiao Greg , Head Tim , Pratap J. Nick , Williams Regan , Helmig Sara , Geller James , Langham Max , Trobaugh‐Lotrario Angela
Published: February 2019

Children with trisomy 18 are surviving longer and undergoing more aggressive life‐sustaining therapy. This report describes two patients with trisomy 18 and hepatoblastoma (HB) successfully resected in the setting of significant pulmonary hypertension. Forty‐four previously published cases of the association between HB and trisomy 18 are reviewed. With careful multidisciplinary preoperative planning, successful resection of HB in children with trisomy 18 who have significant pulmonary hypertension is feasible. Because HB and trisomy 18 are increasing in prevalence, the need for timely liver tumor resection in the setting of pulmonary hypertension will be more common.
N‐doped C‐dot embedded fluorescent and thermo‐responsive p(NIPAAm) microgel composites
Authors: Demirci Sahin , Sahiner Nurettin
Published: February 2019

In this study, the synthesis of N‐doped C‐dot embedding poly(N‐isopropylacrylamide) (p(NIPAAm)) particle composites via surfactant‐free emulsion polymerization technique was reported. The fluorescent property of N‐doped C‐dot combined with thermo‐responsive properties of p(NIPAAm) particles (p(NIPAAm)/C‐dot) render smart materials with intriguing properties. The particle size and volume phase transition temperature (VPTT) values of p(NIPAAm) based particles was altered in accord with the amount of embedded N‐doped C‐dot within p(NIPAAm) particles between 1,000–750 nm and 35.4–37.2°C, respectively. On the other hand, N‐doped C‐dot within p(NIPAAm) particles was afforded fluorescent properties with emission peak at around 460 nm. The effect of the amount of N‐doped C‐dot within p(NIPAAm) particles, temperature and pH were investigated on the fluorescent properties of N‐doped C‐dot embedded p(NIPAAm) particle composite. POLYM. COMPOS., 40:3895–3903, 2019. © 2019 Society of Plastics Engineers
Tolvaptan for Volume Management in Heart Failure
Authors: Gunderson Erik G. , Lillyblad Matthew P. , Fine Michelle , Vardeny Orly , Berei Theodore J.
Published: February 2019

Volume management in acute decompensated and chronic heart failure (HF) remains a significant challenge. Although progress has been made in the development of mortality‐reducing neurohormonal regimens in the reduced ejection fraction population, no clinical trial has yet demonstrated anything more than symptomatic relief or biomarker reduction with pharmacotherapeutic volume‐based interventions made in the acutely decompensated individual or those with evolving outpatient congestion. As the number of patients with HF continues to grow, in addition to HF‐related hospitalizations, identifying therapies that have the potential to aid in diuresis more safely and efficaciously is paramount to decreasing inpatient length of stay and preventing unnecessary admissions. More recently, a significant amount of research has been dedicated to the use of vasopressin antagonists, specifically tolvaptan, as adjunctive therapy to loop and thiazide diuretics. Although these agents do not seem to have a pervasive role in fluid management in the acute decompensated and chronic HF populations, they are effective tools to have available for specific clinical situations. This review summarizes the literature surrounding the use of tolvaptan for volume management in congestive HF, as well as offering practical guidance for use of this agent.
Study on melting and polymorphic behavior of poly(decamethylene terephthalamide)
Authors: Li Ming
Published: February 2019

This work describes the melting and polymorphic behavior of poly(decamethylene terephthalamide) (PA 10T). Both solution‐crystallized (SC) and melt‐crystallized (MC) PA 10T show double melting endotherms in DSC. The SC crystal form melts at 260–300°C giving the first melting endotherm, and meanwhile undergoes a polymorphic transition forming the MC crystal form. The subsequent melting of the MC crystal form gives the second melting endotherm at 300–325°C. This irreversible polymorphic transition is confirmed by variable‐temperature WAXD and IR. Dynamic mechanical thermal analysis (DMTA) shows a glass transition temperature (Tg) at 127°C and the presence of an α′ transition at 203°C (0.1 and 1 Hz). This transition could be confirmed by DSC and variable‐temperature WAXD experiments. The α′ transition correlates with a reversible thermal process and a sudden change in intersheet spacing. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019, 57, 465–472
Feasibility and acceptance of the CaringGuidance web‐based, distress self‐management, psychoeducational program initiated within 12 weeks of breast cancer diagnosis
Authors: Lally Robin M. , Bellavia Gina , Gallo Steven , Kupzyk Kevin , Helgeson Vicki , Brooks Catherine , Erwin Deborah , Brown Jean
Published: February 2019

Objective

Limited clinical resources create barriers to quality management of cancer‐related distress. CaringGuidance After Breast Cancer Diagnosis is a web‐based, patient‐controlled, psychoeducational program of cognitive‐behavioral, coping and problem‐solving strategies aimed at early post‐diagnosis distress reduction without clinical resources. This study evaluated the feasibility of recruiting and retaining newly diagnosed women to 12 weeks of CaringGuidance and program acceptance.

Methods

Women with stage 0 to II breast cancer diagnosed within the prior 3 months were recruited from clinics and communities in four states, from 2013 to 2015 and randomized to 12 weeks of CaringGuidance plus usual care (n = 57) or usual care alone (n = 43). Recruitment, retention, and program use were tracked. Using standard and study‐derived measures, demographic and psychological variables were assessed at baseline and monthly and program satisfaction at 12 weeks.

Results

Of 139 women screened, 100 enrolled, five withdrew, and 12 were lost to follow‐up (83% retention rate). Total program engagement was positively associated with greater baseline intrusive/avoidant thoughts. Intervention participants (92%) believed CaringGuidance would benefit future women and was easy to use. Sixty‐six percent believed CaringGuidance helped them cope. Women used program content to change thoughts (49%) or behaviors (40%). Stress in the previous year was positively associated with reports that CaringGuidance was reassuring and helpful.

Conclusions

Feasibility and acceptance of CaringGuidance was demonstrated pointing to the program's potential as a cancer‐distress self‐management intervention. Future research will explore program feasibility and acceptability in other regions of the United States, leading to clinical implementation trials.
A measurement method for determining the correlation between the amount of haemolysis and the electric current in low‐temperature plasma treatment
Authors: Miyamoto Kenji , Ikehara Yuzuru
Published: February 2019

We have developed a low‐temperature plasma apparatus as a surgical device for haemostasis. A quantitative measurement method and system that analyses the relationship between the properties of low‐temperature plasma and blood components are necessary to evaluate the performance and safety of plasma apparatuses. In a previous study, we revealed that low‐temperature plasma haemolyses erythrocytes, and the released haemoglobin contribute to clot formation; haemolysis by low‐temperature plasma occurs when the value of the current originating from low‐temperature plasma exceeds a certain threshold. In the current study, we examined the correlation between the haemoglobin concentration and the electric current value through experiments using our improved measurement system. We propose a method to control the haemolysis effect by adjusting the plasma current value.
Process optimization of methane reforming to syngas using Gliding Arc Plasmatron
Authors: Shenoy Shridhar B. , Rabinovich Alexander , Fridman Alexander , Pearlman Howard
Published: February 2019

The main objective of this paper is analysis of the advantages of using non‐thermal gliding arc plasma for natural gas reforming to Syngas. The key feature of gliding arc reforming process is that non‐equilibrium plasma is used only as a catalyst thus ensuring minimum energy consumption (3–5% of fuel heating value). The dependence of Specific Energy Requirement (SER), Electric Power Consumption and produced syngas composition on incoming air/methane flow rate, O/C ratio and preheating temperature is discussed. The optimal parameters of the process (SER −0.25 kW‐h m−3 of syngas at O/C ratio – 1.3 and electric power consumption <5%) could be achieved by preheating incoming air/methane mixture with highly efficient heat exchanger (simulated in experiments by external electrical heater). With the aim of possible industrial applications, the results obtained are at high flowrate (40–80 SLPM), O/C ratio 1.1–1.5, preheating temperature − 800 K and high Syngas concentration (H2‐ 25–27 vol.%; CO 15–17 vol%).
Shielding‐gas‐controlled atmospheric pressure plasma jets: Optical emission, reactive oxygen species, and the effect on cancer cells
Authors: Kapaldo James , Han Xu , Ptasinska Sylwia
Published: February 2019

Shielding‐gas‐controlled helium atmospheric pressure plasma jets (APPJs) in contact with conductive or nonconductive liquid are investigated. Two‐dimensional (2D) optical emission intensity maps of plasma species directly above the liquid, the 2D distribution of reactive oxygen species (ROS) on the liquid surface, and the 2D distribution of DNA double‐strand breaks (DSBs) induced in epithelial cancer cells are provided. When conductive liquid is used, the plasma jet develops a glow‐discharge‐like structure at the liquid surface. The ROS distribution is found to be strongly dependent on both the shielding gas composition and the liquid conductivity. The amount of DNA DSBs is found to be largest when using N2 shielding gas and almost negligible when using O2 shielding gas.