bluuebunny/crossref_metadata_2025 huggingface dataset:
Multiple anthropogenic interventions drive puma survival following wolf recovery in the Greater Yellowstone Ecosystem
Authors: Elbroch L. Mark , Marescot Lucile , Quigley Howard , Craighead Derek , Wittmer Heiko U.
Published: June 2018

Humans are primary drivers of declining abundances and extirpation of large carnivores worldwide. Management interventions to restore biodiversity patterns, however, include carnivore reintroductions, despite the many unresolved ecological consequences associated with such efforts. Using multistate capture–mark–recapture models, we explored age‐specific survival and cause‐specific mortality rates for 134 pumas (Puma concolor) monitored in the Greater Yellowstone Ecosystem during gray wolf (Canis lupus) recovery. We identified two top models explaining differences in puma survivorship, and our results suggested three management interventions (unsustainable puma hunting, reduction in a primary prey, and reintroduction of a dominant competitor) have unintentionally impacted puma survival. Specifically, puma survival across age classes was lower in the 6‐month hunting season than the 6‐month nonhunting season; human‐caused mortality rates for juveniles and adults, and predation rates on puma kittens, were higher in the hunting season. Predation on puma kittens, and starvation rates for all pumas, also increased as managers reduced elk (Cervus elaphus) abundance in the system, highlighting direct and indirect effects of competition between recovering wolves and pumas over prey. Our results emphasize the importance of understanding the synergistic effects of existing management strategies and the recovery of large, dominant carnivores to effectively conserve subordinate, hunted carnivores in human‐dominated landscapes.
Initial performance evaluation of centimeter‐class augmentation system using Quasi‐Zenith Satellite System
Authors: Namie Hiromune , Okamoto Osamu , Kubo Nobuaki , Yasuda Akio
Published: June 2018

On September 11, 2010, the Quasi‐Zenith Satellite (QZS) “Michibiki” was launched from the Tanegashima island as the first satellite for positioning in Japan. We have attempted to fix positions using LEX data with centimeter‐class augmentation service for centimeter‐level positioning augmentation signal via Michibiki. The authors tried to fix positions by using LEX data at a stationary point and in a moving car in real time and with postprocessing. They could confirm no more than 2.22 cm as the average positioning error and discrepancy of postpositioning.
Blood flow simulation during flow‐mediated dilation
Authors: Asami Naoya , Yamazaki Yoichi , Kamiyama Yoshimi
Published: June 2018

Endothelial dysfunction is known to be the early stage of arteriosclerosis. The flow‐mediated dilation (FMD) test is the most commonly used method to diagnose the endothelial function. The test measures the maximum vasodilation (FMD response) on the brachial artery induced by the increases in blood flow after cuff deflation on the forearm. The vessel diameter must be captured clearly with the ultrasonic probe during the test. The vasodilation is induced in response to changes in the mechanical property of the vessel wall due to the blood flow stimulation. The changes are supposed to affect the pulsatile flow, but the influence of continuous behavior of vascular property on hemodynamics has not been clarified. In this study, in order to clarify the influence of the FMD response on hemodynamics, we propose a mathematical model that can simulate hemodynamics and vasomotor responses. As a result, it was shown that vessel wall dynamics affected the pulsatile flow. This result suggests that the endothelial function can be evaluated from blood flow.
The food web perspective on aquatic biofilms
Authors: Weitere Markus , Erken Martina , Majdi Nabil , Arndt Hartmut , Norf Helge , Reinshagen Michael , Traunspurger Walter , Walterscheid Anja , Wey Jennifer K.
Published: June 2018

Biofilms, the complex communities of microbiota that live in association with aquatic interfaces, are considered to be hotspots of microbial life in many aquatic ecosystems. Although the importance of attached algae and bacteria is widely recognized, the role of the highly abundant biofilm‐dwelling micrograzers (i.e., heterotrophic protists and small metazoans) is poorly understood. Studies often highlight the resistance of bacterial biofilms to grazing within the microbial food web and therefore argue that the micrograzers have a modulating role (i.e., have effects on biofilm phenotype) rather than a direct trophic role within biofilms. In the present review, we show that this view comes too short, and we establish a conceptual framework of biofilm food webs consisting of three major elements. (1) Energy pathways and subsidization from plankton. As inhabitants of interfaces, biofilm‐dwelling grazers potentially access both planktonic organisms and surface‐associated organisms. They can play an important role in importing planktonic production into the biofilm food web and thus in the coupling of the planktonic and benthic food webs. Nevertheless, specialized grazers are also able to utilize significant amounts of autochthonous biofilm production. (2) Horizontal complexity of the basal food web. While bacteria and algae within biofilms are edible in general, food quality and accessibility of both bacteria and algae can differ considerably between different prey phenotypes occurring during biofilm formation with respect to morphology, chemical defense, and nutrient stoichiometry. Instead of considering bacteria and algae within biofilms to be generally resistant to feeding by micrograzers, we suggest considering a horizontal food‐quality axis to be at the base of biofilm food webs. This food quality gradient is probably associated with increasing costs for the micrograzers. (3) Vertical food web complexity and food chain length. In addition to the consumption of bacteria and algae, many predatory micrograzers exist within biofilm food webs. With the help of video microscopy, we were able to demonstrate the existence of a complex food web with several trophic levels within biofilms. Our conceptual framework should assist in integrating food web concepts and processes into whole‐biofilm budgets and in understanding food‐web‐related interactions within biofilms.
Synthesis, characterization, and crystal structure of novel bulky phenyl‐bridged α‐diimine binucleating ligands
Authors: Mechria Ali , Msaddek Moncef
Published: June 2018

A series of sterically and electronically modulated phenyl‐bridged α‐diimine ligands L1–L6 of the general formula Ar‐N=C(Me)‐C(Me)=N‐C6H4‐N=C(Me)‐C(Me)=N‐Ar have been synthesized (L1 : Ar = 2,6‐iPr2‐C6H3; L2: Ar = 2,6‐Me2‐C6H3; L3: 4‐Me‐C6H4; L4: Ar = 4‐Et‐C6H4; L5: Ar = 2,4,6‐Cl3‐C6H2; L6: Ar = 4‐Cl‐C6H4). All of which have been characterized by 1H NMR, 13C NMR, IR, and elemental analysis. In addition, the effect of the electronic modification was studied by UV–Vis spectroscopy, and the structure of a representative ligand was confirmed by single‐crystal X‐ray diffraction. Moreover, a DFT electronic structure of the same ligand has been determined.
Linking transit times to catchment sensitivity to atmospheric deposition of acidity and nitrogen in mountains of the western United States
Authors: Clow David W. , Mast M. Alisa , Sickman James O.
Published: June 2018

Transit times are hypothesized to influence catchment sensitivity to atmospheric deposition of acidity and nitrogen (N) because they help determine the amount of time available for infiltrating precipitation to interact with catchment soil and biota. Transit time metrics, including fraction of young water (Fyw) and mean transit time (MTT), were calculated for 11 headwater catchments in mountains of the western United States based on differences in the amplitude of the seasonal signal of δ18O in streamflow and precipitation. Results were statistically compared with catchment characteristics to elucidate controlling mechanisms. Transit times also were compared with stream solute concentrations to test the hypothesis that transit times are a primary influence on weathering rates and biological assimilation of atmospherically deposited N. Results indicate that transit times in the study catchments are strongly related to soil, vegetation, and topographic characteristics, with barren terrain (bare rock and talus) and steep slopes linked to high Fyw and short MTT, whereas forest soil (hydrogroup B) was linked to low Fyw and greater MTT. Concentrations of silicate weathering products (Na+ and Si) were negatively related to Fyw and barren terrain, and positively related to MTT and forest soil, supporting the concept that weathering fluxes and buffering capacity tend to be low in alpine areas due to short transit times. Nitrate concentrations were positively related to N deposition, catchment slope, and barren terrain, and negatively related to forest, indicating that hydrologic and/or biogeochemical processes associated with steep slopes limit uptake of atmospherically deposited N by biota. Interannual and seasonal variability in transit times and source water contributions in the study catchments was substantial, reflecting the influence of strong temporal variations in snowmelt inputs in high‐elevation catchments of the western United States. Results from this study confirm that short transit times in these areas are a key reason they are highly sensitive to atmospheric pollution and climate change.
Production, characterization and testing of antibacterial PVA membranes loaded with HA‐Ag3PO4 nanoparticles, produced by SC‐CO2 phase inversion
Authors: Baldino Lucia , Aragón Javier , Mendoza Gracia , Irusta Silvia , Cardea Stefano , Reverchon Ernesto
Published: June 2018

BACKGROUND

Silver‐loaded hydroxyapatite nanoparticles were incorporated into poly(vinyl alcohol) (PVA) membranes obtained by supercritical CO2 (SC‐CO2) assisted phase inversion. Ag3PO4 crystals of 2.2 ± 0.6 nm were dispersed in synthesized needle‐like hydroxyapatite nanoparticles (20 × 65 nm) and were uniformly deposited on the internal surfaces of the PVA membranes. Operative conditions to produce membranes by SC‐CO2, PVA concentration and the effect on membrane porosity and morphology were studied.

RESULTS

Solutions at 20% w/w PVA produced membranes with cellular morphology and nanoporous walls, whereas 30% and 50% w/w solutions produced nanostructured membranes. Silver ions were released from PVA membranes mainly by diffusion according to the Peppas–Sahlin model. Membranes obtained at 20% w/w PVA showed a significant E. coli inhibition at an Ag concentration of 9 ppm, reaching the minimal inhibitory concentration (MIC) and improving the bactericidal activity of the nanoparticles.

CONCLUSION

A concentration of Ag3PO4 crystals of about 22 ppm was calculated as being capable of completely destroying these bacteria, reaching the minimum bactericidal concentration (MBC). © 2018 Society of Chemical Industry
The effects of thermal stress on the early development of the lizard Anolis sagrei
Authors: Sanger Thomas J. , Kyrkos Judith , Lachance Dryden J. , Czesny Beata , Stroud James T.
Published: June 2018

Across the globe terrestrial ectotherms—amphibians and non‐avian reptiles—are facing a range of emerging challenges. Increasing global temperatures, in particular, are affecting all aspects of ectotherm biology and life history. Embryonic development is a thermally sensitive period of the organismal lifecycle, yet the impacts of thermal stress on the early development of ectotherms have significantly lagged behind studies of later stages and adult thermal physiology. Morphogenesis, the stage where the major anatomical systems are actively forming, is particularly sensitive to thermal stress, yet is not studied as often as later stages where growth is the primary process happening within the egg. Here, we focus on the effects of thermal stress on the first 12 days of development, the stages of morphogenesis, in the lizard Anolis sagrei. We examine the resiliency of the early developmental stages to heat stress by incubating eggs at temperatures that parallel conditions observed today and predicted over the next 50–100 years of projected climate change. Our results suggest that some anole nests are currently at the thermal limits for which the early embryonic stages can properly develop. Our results emphasize the importance of studying early embryonic stages of development and the importance of studying stage‐specific effects of thermal stress on squamate development.
Developmental plasticity in reptiles: Critical evaluation of the evidence for genetic and maternal effects on temperature‐dependent sex determination
Authors: Roush Danielle , Rhen Turk
Published: June 2018

We critically review literature that examines variation in temperature‐dependent sex determination (TSD) within species. Although variation in sex ratio among clutches of eggs from different females is common in reptiles with TSD, the underlying mechanism that causes this variation is not clear. Authors have made claims about genetic variation in TSD and maternal effects on TSD. The latter type of study usually focuses on maternally derived steroids in egg yolk. Here, we outline the types of experiments and data required to unequivocally demonstrate that variation in sex ratio among clutches (1) has a genetic basis, (2) is caused by maternally derived steroids, or (3) is influenced by both factors. To date, few studies have met these requirements.
Thermal plasticity due to parental and early‐life environments in the jacky dragon (Amphibolurus muricatus)
Authors: So C. K. Janelle , Schwanz Lisa E.
Published: June 2018

Developmental plasticity creates marked variation in individual phenotypes when the environment is patchy, such as when the thermal environment varies. Plasticity may occur in response to the environment experienced during an individual's lifetime or to the environment experienced by parents (transgenerational plasticity), and may be adaptive if it enhances fitness. In particular, plasticity in thermal traits, such as preferred temperatures and thermal limits, may improve performance and fitness based on temperatures in the local environment. This study examined the influence of parental and offspring thermal environments (duration of access to a basking lamp) on offspring thermal traits (preferred temperatures and panting threshold) in jacky dragons (Agamidae: Amphibolurus muricatus). Long‐bask parental environments led, indirectly, to higher preferred temperatures of offspring due to increased offspring body mass compared to offspring of short‐bask parents. The increase in median temperature preference was associated with a higher voluntary minimum body temperature and a narrower preference range, suggesting tradeoffs in thermal behavior and a matching of offspring preferences to the parental environment. Parental thermal treatment did not influence offspring panting threshold. Instead, the panting threshold tended to be higher in offspring that were reared in the long‐bask treatment compared to those in the short‐bask treatment, suggesting longer basking environments increased thermal tolerance. Parental and offspring thermal environment did not exhibit any interactive effect on thermal traits. The results indicate that thermal environments experienced by lizards can have both transgenerational and within‐generation impacts on thermal traits, thus influencing how populations respond to fluctuating or changing climates.
Same‐day antiretroviral therapy (ART) initiation in pregnancy is not associated with viral suppression or engagement in care: A cohort study
Authors: Langwenya Nontokozo , Phillips Tamsin K , Brittain Kirsty , Zerbe Allison , Abrams Elaine J , Myer Landon
Published: June 2018

Introduction

Many prevention of mother‐to‐child HIV transmission programmes across Africa initiate HIV‐infected (HIV positive) pregnant women on lifelong antiretroviral therapy (ART) on the first day of antenatal care (“same‐day” initiation). However, there are concerns that same‐day initiation may limit patient preparation before starting ART and contribute to subsequent non‐adherence, disengagement from care and raised viral load. We examined if same‐day initiation was associated with viral suppression and engagement in care during pregnancy.

Methods

Consecutive ART‐eligible pregnant women making their first antenatal care (ANC) visit at a primary care facility in Cape Town, South Africa were enrolled into a prospective cohort between March 2013 and June 2014. Before July 2013, ART eligibility was based on CD4 cell count ≤350 cells/μL (“Option A”), with a 1 to 2 week delay from the first ANC visit to ART initiation for patient preparation; thereafter all women were eligible regardless of CD4 cell count (“Option B+”) and offered ART on the same day as first ANC visit. Women were followed with viral load testing conducted separately from routine ART services, and engagement in ART services was measured using routinely collected clinic, pharmacy and laboratory records through 12 months postpartum.

Results

Among 628 HIV‐positive women (median age, 28 years; median gestation at ART start, 21 weeks; 55% newly diagnosed with HIV), 73% initiated ART same‐day; this proportion was higher under Option B+ versus Option A (85% vs. 20%). Levels of viral suppression (viral load <50 copies/mL) at delivery (74% vs. 82%) and 12 months postpartum (74% vs. 71%) were similar under same‐day versus delayed initiation respectively. Findings were consistent when viral suppression was defined at <1000 copies/mL, after adjustment for demographic/clinical measures and across subgroups of age, CD4 and timing of HIV diagnosis. Time to first viral rebound following initial suppression did not differ by timing of ART initiation nor did engagement in care through 12 months postpartum (same‐day = 73%, delayed = 73%, p = 0.910).

Conclusions

These data suggest that same‐day ART initiation during pregnancy is not associated with lower levels of engagement in care or viral suppression through 12 months post‐delivery in this setting, providing reassurance to ART programmes implementing Option B+.
Isolation and molecular characterization of biosurfactant producing yeasts from the soil samples contaminated with petroleum derivatives
Authors: Yalçın Hüsniye T. , Ergin‐Tepebaşı Gülşah , Uyar Ebru
Published: June 2018

In this study, 65 yeast strains were isolated from different environmental samples contaminated with various petroleum hydrocarbons such as activated sludges and soil samples from automobile workshops. The yeast isolates were tested for biosurfactant production using various screening methods such as parafilm M test, oil displacement assay, drop collapse assay, determination of surface tension reduction, and emulsification index. Nineteen of the isolates were found positive for biosurfactant production and their molecular characterizations were carried out by sequencing analysis of the ITS1‐5.8S‐ITS2 region and D1/D2 domain of 26S rDNA. The results indicated that these strains were from a wide range of yeast genera including Rhodotorula, Candida, Yarrowia, Geotrichum, Galactomyces, and Cystobasidium. The studies to determine the emulsification index revealed that the biosurfactants produced by Yarrowia lipolytica strains (TEMGS33, TEMOS12, and TEMOS14) and Apiotrichum loubieri strain (TEMOS16) were the most potent and capable of forming stable emulsions with emulsion index (E24) up to 68%. In addition, quantitative measurements of the surface tension reduction of the biosurfactants produced by these strains were carried out by Du Noüy ring method. Biosurfactants produced from Yarrowia lipolytica strain TEMGS33 and Apiotrichum loubieri strain TEMOS16 gave the best results reducing the surface tension to 34.7 ± 1.15 and 35.3 ± 0.55 mN m−1, respectively. Based on these data, biosurfactants from Yarrawia lipolytica strains (TEMGS33, TEMOS12, and TEMOS14) and Apiotrichum loubieri strain (TEMOS16) showed promising results and might be implemented in numerous industrial fields such as bioremediation and food industry.
Feather degrading, phytostimulating, and biocontrol potential of native actinobacteria from North Eastern Indian Himalayan Region
Authors: Kshetri Pintubala , Roy Subhra S. , Sharma Susheel K. , Singh Thangjam S. , Ansari Meraj A. , Sailo Blessa , Singh Surender , Prakash Narendra
Published: June 2018

Twelve actinobacterial strains were isolated from tomato rhizospheric soil from Manipur, a state in North East Indian Himalayan Region and screened for keratinolytic and plant growth promoting traits. Nine promising isolates were identified as Streptomyces species using partial 16S rRNA gene sequencing. Among the seven isolates showing chicken feather degradation activity, three keratinolytic strains RCM‐SSR‐2, ‐6, and ‐12 were found to be the most efficient feather degrading strains achieving 90% feather weight loss within 48 h of incubation. They also showed maximum keratinase and soluble peptide production. Strain RCM‐SSR‐2, ‐5, ‐6, ‐8, and ‐11 showed positive results for all plant growth promoting traits tested. Maximum indole‐3‐acetic acid production was exhibited by RCM‐SSR‐6. Strain RCM‐SSR‐1, ‐2, ‐5, ‐6, ‐9, and ‐11 showed antagonistic activity against three important plant pathogens. Feather hydrolysate of RCM‐SSR‐6 was also evaluated for in vitro seed germination test using garden pea seeds. Higher concentration of feather protein hydrolysate (3 mg ml−1) inhibited shoot and root length of the germinating embryo. However, lower concentration (0.01 mg ml−1) of feather protein hydrolysate promoted seed germination. Among the 12 strains, four isolates namely RCM‐SSR‐1, ‐2, ‐5, and ‐6 were found to be promising as multi‐traits plant growth promoting rhizobacteria for development of organic fertilizer, phytostimulator, and biocontrol agents.
A rapid local backlight dimming method for interlaced scanning video
Authors: Zhang Tao , Wang Hao , Chen You‐zhi , Liu Qiang , Li Meng , Lei Zhi‐Chun
Published: June 2018

This paper presents a rapid local backlight dimming method for interlaced video to improve the efficiency of displaying interlaced video. In the proposed method, we combine the line average deinterlacing algorithm with the local backlight dimming algorithm. In order to reduce the computational complexity and the backlight power consumption, three novel methods are proposed. The first is to add the sparse method to process the deinterlaced image. Second, the improved dynamic threshold method is used to calculate the dimming factor. And third, the odd field and even field of the same frame use the same backlight brightness to do backlight dimming. The simulation results show that the proposed method can reduce the computational complexity and power consumption, and the experiment results verify that the method can provide high display effect.
Accelerated tattoo removal with acoustic shock wave therapy in conjunction with a picosecond laser
Authors: Vangipuram Ramya , Hamill Selina S. , Friedman Paul M.
Published: June 2018

Background

Conventional tattoo removal consists of single‐pass treatments, spaced 7–8 weeks apart, for a total of 7–10 sessions. A major limiting factor of this procedure is the development of cavitation bubbles and vacuoles within the epidermis and dermis that result from the rapid heating of tattoo particles by the laser. While multiple‐pass methods using the R20 protocol or the PFD patch enhance tattoo removal through epidermal clearance, they have no effect on deep‐intradermal pigment associated vacuoles that arise from treatment with lasers such as the Q‐switched laser.

Methods

A 28‐year‐old female with Fitzpatrick skin Type V presented for treatment of a 6‐year‐old professional black tattoo on the left ventral wrist. She underwent three treatment sessions at 6–8 week intervals using a commercial 1,064‐nm picosecond Nd:YAG laser (PicoWay; Candela, Wayland, MA) and a perfluorodecalin (PFD) patch (Merz; Raleigh, NC). At each treatment session, she received two passes with 1,064‐nm, 4‐mm spot size, a fluence ranging from 2.8 to 3.2 J/cm2 and a laser repetition rate of 2 Hz. Between laser passes and following the final laser pass, the medial portion of the tattoo was treated with acoustic shock wave therapy (ASWT) using the Zwave device (Zimmer Medizin Systems; Irvine, CA) with 90 mJ, 22 Hz, and 1,200 pulses.

Results

After three treatment sessions, there was 80% clearance of the medial portion of the tattoo that received the ASWT compared with 60% clearance of the lateral portion of the tattoo that was treated with the picosecond 1,064‐nm Nd:YAG laser and PFD patch alone. In the days following each treatment session, the patient noted consistently less edema, erythema and epidermal crusting on the portion of the tattoo that received the ASWT.

Conclusion

We report a case of 80% tattoo clearance with ASWT in a patient with Fitzpatrick type V skin compared with 60% clearance with the picosecond 1064‐nm Nd:YAG laser and PFD patch alone. The concurrent use of the PFD patch, which facilitated multi‐pass treatments, may have also increased tattoo fading in this patient. ASWT may enhance tattoo clearance by increasing lymphatic drainage and increasing metabolic activity in the treated area, thereby accelerating the clearance of dermal pigment vacuoles produced by the picosecond laser and minimizing epidermal side effects such as erythema, edema, and crusting. Lasers Surg. Med. 50:890–892, 2018. © 2018 Wiley Periodicals, Inc.
Q‐matrix method for the analysis and performance evaluation of unreliable M/M/1/N queueing model
Authors: Afroun Faïrouz , Aïssani Djamil , Hamadouche Djamel , Boualem Mohamed
Published: June 2018

In this work, we study an M/M/1/N queuing system with multiple vacations, Bernoulli feedback, balking, reneging and retention of the impatient customers, and the possibility of a server breakdown and repair. First, by using the Q‐matrix (infinitesimal generator matrix) method, we obtain the steady‐state probabilities of the system. Then, some useful performance measures are derived. Finally, the influence of the reliability parameters on the performance measures of the system has been examined numerically.
The existence of nontrivial solution for biharmonic equation with sign‐changing potential
Authors: Su Yu , Chen Haibo
Published: June 2018

In this paper, we study the following biharmonic equation:

urn:x-wiley:mma:media:mma5127:mma5127-math-0001
where N⩾5,ν ∈ (0,ν0],1  <  q  <  2,Δ2u  =  Δ(Δu) and Vλ(x)  =  λa(x) − b(x) with λ > 0. Firstly, we prove the bipolar Rellich inequality. Secondly, by using bipolar Rellich inequality, Gigliardo‐Nirenberg inequality, and Ekeland variational principle, we prove the existence of nontrivial solution for problem Bν.
Diet Enriched with Olive Oil Attenuates Placental Dysfunction in Rats with Gestational Diabetes Induced by Intrauterine Programming
Authors: Capobianco Evangelina , Gomez Ribot Dalmiro , Fornes Daiana , Powell Theresa L. , Levieux Cecilia , Jansson Thomas , Jawerbaum Alicia
Published: June 2018

Scope

Offspring from rats with mild diabetes develop gestational diabetes mellitus (GDM). We tested the hypothesis that an olive oil‐supplemented diet attenuates placental oxidative stress/inflammation, activation of mTOR signaling, and inhibition of peroxisome proliferator‐activated receptor γ (PPARγ) and fetal overgrowth in GDM offspring from mild diabetic rats.

Methods and results

Female offspring from rats with mild diabetes (group that developed GDM) and controls were fed with either a standard diet or a 6% olive oil‐supplemented diet during pregnancy. On day 21 of pregnancy, plasma glucose levels in mothers and fetuses were increased in the GDM group independently of the diet. Fetal overgrowth and activation of placental mTOR signaling were partially prevented in the olive oil‐treated GDM group. Placental PPARγ protein expression was decreased in GDM rats, independently of the diet. However, increases in placental lipoperoxidation, connective tissue growth factor, and matrix metalloproteinase 2 levels were prevented by the olive oil‐enriched diet.

Conclusion

Diets enriched with olive oil attenuate placental dysfunction and fetal overgrowth in rats with GDM induced by intrauterine programming.
Zinc oxide nanoparticles as contrast‐enhancing agents for microwave imaging
Authors: Lahri Rachita , Rahman Mohammed , Wright Michael , Kosmas Panagiotis , Thanou Maya
Published: June 2018

Purpose

Microwave imaging/sensing is an emerging technology that shows potential for healthcare diagnostic applications, particularly in breast cancer detection. This technique estimates the anatomically variant dielectric properties of the breast. Similar to other imaging modalities, nanoparticles (NPs) could potentially be utilized as contrast agents to increase contrast between healthy and malignant tissues.

Methods

In this study, aqueous suspensions of NPs such as surface‐modified single‐walled carbon nanotubes, zinc oxide, and silicon dioxide are studied to assess their potential effective contrast for microwave imaging. Morphology characterization of the NPs has been achieved using atomic force microscopy (AFM) and scanning electron microscopy (SEM). The size and stability of colloidal dispersions have been characterized by dynamic light scattering technique (DLS) and Ultraviolet‐visible spectrophotometry (UV‐Vis). The dielectric characterization of the aqueous‐based colloidal suspensions is recorded over the microwave frequency range between 1 and 4 GHz.

Results

Zinc oxide NP dispersion has shown an increase in the dielectric constant compared to the background medium. Furthermore, PEGylation of ZnO NPs can achieve a valid increase in the dielectric constant compared to water, which was shown to be concentration dependent.

Conclusion

These results suggest that ZnO nanomaterials have the potential to be used in biomedical applications such as breast imaging to improve diagnostic capabilities.
Factors affecting recruitment and retention of nurses who deliver clinical research: A qualitative study
Authors: Boulton Mary G. , Beer Sally
Published: June 2018

Aim

To provide a better understanding of the factors affecting recruitment and retention of clinical research nurses.

Design

Qualitative exploratory design.

Methods

An on‐line questionnaire comprising open‐ended and fixed‐choice questions was completed by 121 clinical research nurses. Seven focus groups were held with a subgroup of 26 participants. Data were analysed using inductive thematic analysis.

Results

Participants were attracted to a research nurse post by an interest in research itself, a desire for a change or to achieve personal objectives. The majority expected to continue in a research post for the next 5 years, while others expected to move on to research management, a clinical post or retirement; few had ambitions to become an independent researcher. Factors identified in focus groups as leading to intentions to leave research included desire for further change, concern about loss of clinical skills, rebalancing family/work responsibilities, short‐term contracts, unsupportive employers and limited career progression.
What Interventions Work Best for Families Who Experience Homelessness? Impact Estimates from the Family Options Study
Authors: Gubits Daniel , Shinn Marybeth , Wood Michelle , Brown Scott R. , Dastrup Samuel R. , Bell Stephen H.
Published: June 2018

What housing and service interventions work best to reduce homelessness for families in the United States? The Family Options Study randomly assigned 2,282 families recruited in homeless shelters across 12 sites to priority access to one of three active interventions or to usual care in their communities. The interventions were long‐term rent subsidies, short‐term rent subsidies, and transitional housing in supervised programs with intensive psychosocial services. In two waves of follow‐up data collected 20 and 37 months later, priority access to long‐term rent subsidies reduced homelessness and food insecurity and improved other aspects of adult and child well‐being relative to usual care, at a cost 9 percent higher. The other interventions had little effect. The study provides support for the view that homelessness for most families is an economic problem that long‐term rent subsidies resolve and does not support the view that families must address psychosocial problems to succeed in housing. It has implications for focusing government resources on this important social problem.
Investigation on wear behaviors and worn surface morphology of surface treated palmyra fruit fiber/polyester composites to appraise the effects of fiber surface treatments
Authors: Irullappasamy Sankar , Durairaj Ravindran , Irulappasamy Siva , Manoharan Thirukumaran
Published: June 2018

Dry sliding wear behaviors and identified wear mechanisms of untreated/surface treated Palmyra fruit fiber reinforced polyester composites have been presented. The wear tests are conducted on a pin‐on‐disc wear tester under ambient conditions. Wear mechanisms are studied through SEM and stereo microscopic analysis on the worn surface and the counter body, respectively. From the results, it is recognized that the wear resistance of the composites is better than the untreated fiber reinforced composites and extreme in the composites made up of NaOH‐treated fibers. The leading fiber failure mechanisms identified in the untreated fiber reinforced polyester composites are fiber debonding and fiber crack. Some important wear mechanisms that are identified on the worn surfaces are adhesion, surface fatigue, plastic deformation, and crazing. POLYM. COMPOS., 39:2029–2035, 2018. © 2016 Society of Plastics Engineers
Enhanced mechanical and thermal properties of polypropylene/cellulose fibers composites with modified tannic as a compatibilizer
Authors: Yang Jin , Lu Shaorong , Luo Qiyun , Song Laifu , Li Yuqi , Yu Jinhong
Published: June 2018

A novel compatibilizer tannic grafted poly(12‐hydroxy stearate) (TA‐g‐PHS) was synthesized using tannic and 12‐hydroxystearic acid as raw materials through the esterification reaction. The compatibilizer was used to improve the compatibility between polypropylene (PP) and microcrystalline cellulose fibers (MCF). The impact strength and tensile strength of MCF/PP composites modified with the TA‐g‐PHS were 38.51 kJ/m2 and 30.45 MPa when the content loading of TA‐g‐PHS is 3 wt% and MCF is 10 wt%, which were improved by 40.5% and 76.9%, respectively, compared to the MCF/PP composites alone. The melt flow rate improved with the addition of TA‐g‐PHS. And the thermal properties have slightly improved. Moreover, the SEM images of the fracture surfaces display that MCF is relatively well dispersed in the PP matrix by adding TA‐g‐PHS. It can be inferred that the PP and MCF matrix interfacial bonding was strengthened. POLYM. COMPOS., 39:2036–2045, 2018. © 2016 Society of Plastics Engineers
A probabilistic model of the tensile strength of a UD flax–fabric‐reinforced polymer composite
Authors: Andersons J. , Modniks J.
Published: June 2018

In order to fully realize the efficiency of bast fibers or their yarns as reinforcement of polymer composites, they should be aligned. Tensile strength of such composites in the direction of reinforcement has been found to exhibit size effect commensurable with that of unidirectionally reinforced (UD) composites with inorganic fibers, necessitating a probabilistic modeling approach. Strength distribution of a polymer matrix composite reinforced with aligned twisted bast fiber yarns is considered allowing for the strength scatter of elementary fibers, the presence of defects in the form of adjacent fiber breaks, and twist of the yarns. The model is applied to predicting the strength of flax/acrylated epoxidized soy oil resin composite specimens of different sizes. The theoretical prediction is found to be in a reasonable agreement with strength test results. POLYM. COMPOS., 39:2101–2109, 2018. © 2016 Society of Plastics Engineers
Polyurethanes for coatings and adhesives – chemistry and applications
Authors: Golling Florian E , Pires Raul , Hecking Andreas , Weikard Jan , Richter Frank , Danielmeier Karsten , Dijkstra Dirk
Published: June 2018

This review summarizes the past present, and future developments of isocyanate chemistry for polyurethane coatings and adhesives. Over the past 60 years, this field was driven by numerous breakthrough innovations that helped improve coating applications with respect to customer's needs—cementing the features of this outstanding material class. We provide a short introduction on the early beginnings of industrial isocyanate chemistry and then a detailed overview on the building blocks as well as the rich chemistry of the isocyanate group. The synthesis of various derivatives is described. An outlook on the latest developments—new building blocks and new chemistries—is given in the field of isocyanate coating and adhesive chemistry. © 2018 Society of Chemical Industry
Comparing the fertility of Ghanaian migrants in Europe with nonmigrants in Ghana
Authors: Wolf Katharina , Mulder Clara H.
Published: June 2018

The fertility behaviour of migrants is often studied by examining migrants and native nonmigrants in the country of destination. To understand the mechanisms for migrant fertility, it is important to know what distinguishes them from the population they originate from. The Ghanaian sample of the "Migrations between Africa and Europe" project allows us to contrast the fertility of those who never emigrated from Ghana and Ghanaian migrants who are residing in the UK or the Netherlands. First, we estimate discrete‐time hazard models of first birth to evaluate whether first birth timing is influenced by migration. Second, we apply Poisson regression techniques to examine differentials in completed fertility. We find that Ghanaian migrants postpone first childbirth compared with nonmigrants. Differences are largest at ages 20 to 24 for women and 20 to 29 for men. Ghana experiences a typical brain drain, which means that especially the highly skilled emigrate. In our sample, this is particularly true for women. Education seems to be an important determinant of the postponement of first childbirth in Ghana, although we cannot clearly attribute migrants' later first births to their higher level of education. However, our findings on completed fertility reveal that migrants have fewer children than nonmigrants and this difference diminishes considerably if we take into account their level of education. Apparently, migrants do not fully catch up after postponing first childbirth and end up with a lower number of children by the age of 40.
Synthesis and Characterization of TiO2 Micro‐ and Nano‐Structures with Variable Morphology and Aluminum Content
Authors: Vásquez Geraldo Cristian , Taeño María , Maestre David , Cremades Ana
Published: June 2018

Achieving a high surface to volume ratio is of advantage in many applications of semiconducting oxides, which can be obtained by reducing the size of the material toward the nanoscale. Beside size reduction, morphology variability and doping content could also induce differences in the luminescence of structures in the micro‐ and nano‐scale widening their applicability. Elongated rutile TiO2 nano‐ and micro‐structures are fabricated by an evaporation‐deposition method using TiN as precursor at temperatures ranging from 800 to 900 °C. Aluminum doped TiO2 micro‐ and nano‐structures are also grown at 940 °C. The presence of Al hinders the growth of structures and retards the anatase to rutile transition. The as‐grown low dimensional structures are characterized by X‐ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, and cathodoluminescence (CL). The luminescence of the samples depends on the size, morphology, and aluminum content and is mainly dominated by an emission at 1.52 eV and weaker emissions at 2.45 and 2.9 eV, the origin of which is discussed in this work.
Surface Dielectric Tunnel Barrier Induced by Mn Doping in SnO2 Micro‐ and Nanostructures
Authors: Herrera Manuel , Maestre David , Cremades Ana
Published: June 2018

Electrical properties of undoped and Mn doped SnO2 microplates and rods are studied by electron beam induced current (EBIC) in a scanning electron microscope (SEM), and I–V curves acquired at room temperature. AFM measurements reveal the formation of numerous terraces at the (−101) surface of the analyzed Mn‐doped SnO2 microplates, which also exhibit high carrier recombination processes at their central region, as confirmed by combined EBIC and cathodoluminescence (CL) measurements. A diffusion length for minority carriers about 205 nm is obtained by EBIC measurements. Different electrical conduction mechanisms, such as Fowler‐Nordheim, direct tunneling and Poole‐Frenkel, are evaluated in the electrical analysis of the samples. Mn doped microplates show lower conductivity than the undoped microds. Moreover the height of the surface tunnel barrier is increased by Mn doping, as confirmed by the analysis of the I–V curves acquired under transversal configuration. A value of the relative dielectric constant ϵr about 7.3 is estimated for the probed SnO2 microstructures.
Evaluation of TAPEER daily estimates and other GPM‐era products against dense gauge networks in West Africa, analysing ground reference uncertainty
Authors: Gosset Marielle , Alcoba Matias , Roca Remy , Cloché Sophie , Urbani Guillaume
Published: June 2018

A series of multi‐platform rainfall estimates is evaluated at the daily 1° resolution over three dense rain‐gauge networks in West Africa, in Niger, Burkina Faso and Benin, for the period 2012–2016. The quality of the ground reference, its dependence on the number of gauges and the consequences on the validation are discussed. The primary objective of this work is the evaluation of the newly released Tropical Analysis of Precipitation with an Estimation of Errors (TAPEER) daily one‐degree rainfall accumulation from the Megha‐Tropiques mission. Several other multi‐platform products, GSMAP, CMORPH, PERSIANN, TMPA and IMERG, are also evaluated over the same area to put TAPEER performance into perspective. For each product only the version that uses solely satellite information (no gauge adjustment) is used. The analysis concentrates on the heart of the rainy season in West Africa, from June to September. TAPEER exhibits good skill over the region, with a high correlation and a good reproduction of the frequency distribution of the rain rates, especially in the Sahelian region – Niger and Burkina Faso – where the biases are close to zero. The bias is stronger (and negative) in Benin. This overall good performance is stable from year to year. The other products exhibit less bias in Benin and more in the Sahel. CMORPH stands out with relatively good correlations, GSMAP slightly less and PERSIANN has a very strong bias in the Sahel. IMERG, analysed over a shorter period, is also promising.
On the approximation of the inverse error covariances of high‐resolution satellite altimetry data
Authors: Yaremchuk Max , D'Addezio Joseph M. , Panteleev Gleb , Jacobs Gregg
Published: June 2018

High‐resolution (swath) altimeter missions scheduled to monitor the ocean surface in the near future have observation‐error covariances (OECs) with slowly decaying off‐diagonal elements. This property presents a challenge for the majority of the data assimilation algorithms which were designed under the assumption of the diagonal OECs being easily inverted. In this note, we present a method of approximating the inverse of a dense OEC by a sparse matrix represented by the polynomial of spatially inhomogeneous differential operators, whose coefficients are optimized to fit the target OEC by minimizing a quadratic cost function. Explicit expressions for the cost function gradient and the Hessian are derived. The method is tested with an OEC model generated by the SWOT simulator.
On the rapid intensification of Hurricane Wilma (2005). Part IV: Inner‐core dynamics during the steady radius of maximum wind stage
Authors: Qin Nannan , Zhang Da‐Lin , Miller William , Kieu Chanh Q.
Published: June 2018

Recent studies show that some hurricanes may undergo rapid intensification (RI) without contracting the radius of maximum wind (RMW). A cloud‐resolving mesoscale model prediction of Hurricane Wilma (2005) is used herein to examine what controls the RMW contraction and how a hurricane could undergo RI without contraction. Results show that the processes controlling the RMW contraction are different within and above the planetary boundary layer (PBL). In the PBL, radial inflow contributes to contraction, whereas frictional dissipation acts as an inhibiting factor. Above the PBL, radial outflow and vertical motion are the two main factors governing the RMW contraction, with the former inhibiting it. A budget analysis of absolute angular momentum (AAM) shows that the radial AAM flux convergence is the major process accounting for the spin‐up of the maximum rotation in the PBL as the RMW contracts, while the vertical flux divergence of AAM and the friction oppose the spin‐up. During the RI stage with no RMW contraction, the local AAM tendencies in the eyewall are however smaller in magnitude and narrower in width than those during the contracting RI stage. In addition, the AAM following the time‐dependent RMW decreases with time in the PBL and remains nearly constant aloft during the contracting stage, whereas it increases during the non‐contracting stage. These results reveal different constraints for the RMW contraction and RI, and help explain why a hurricane vortex can still intensify after the RMW ceases contraction.
Phenyltetrazole as a New Ligand for Immobilization of Palladium Nanoparticles on SBA‐15: A New Robust Catalyst with High Loading of Pd for Rapid Oxidation and Reduction
Authors: Moghaddam Firouz M. , Saberi Vahid , Kalvani Pedram
Published: June 2018

In this work, a new catalyst based on palladium nanoparticle supported SBA‐15 has been introduced. The designed catalyst was characterized by Scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier‐transform infrared spectroscopy (FT‐IR), Brunauer–Emmett–Teller (BET) surface area analysis, thermo gravimetric analysis (TGA), Energy‐dispersive X‐ray spectroscopy (EDS) and atomic absorption spectroscopy (AAS) analyses. For the first time, phenyltetrazole has been used as a ligand to the functionalization of SBA‐15 to design robust heterogeneous catalyst with high‐loading metal for reduction and oxidation in short time using a low amount of the catalyst.
Synthesis, Optical and Antibacterial, Antifungal Studies on Functionalized Triazolophanes: A New Class of Cyclophane
Authors: Selvarani Sivasamy , Rajakumar Perumal
Published: June 2018

A new class of cyclophanes called triazolophanes has been synthesized by copper (I) catalyzed 1, 3‐dipolar cycloaddition of various aromatic azides to bis‐alkynes under mild conditions at room temperature and characterized by spectral, analytical methods. All the newly synthesized triazolophanes show two strong absorption bands between 243–315 nm. The HOMO‐LUMO energy gap (Eg) was found to lie between 2.56 to 5.06 eV from density functional theory (DFT) calculations and the λmax calculated from the DFT theory was found to lie between 239 to 312 nm which coincides with the observed UV‐vis spectral absorption. All the synthesized triazolophanes show comparable antibacterial and antifungal activity against Escherichia coli, Klebsiella pneumoniae, Staphylococcus aureus, Streptococcus pyogens and Candida glabrata, Candida albicans when tested by resazurin reduction method with streptomycin and Amphotericin‐B as standards, which is supported by molecular docking studies with glide energy of −81.40 and −93.52 Kcal/mol for the triazolophanes 8 derived from 2‐aminothiophenol and orthoxylenyl group and the triazolophane 9 derived from 3‐aminophenol and 2, 6‐diphenyl oxadiazole, respectively.