bluuebunny/crossref_metadata_2025 huggingface dataset:
HIV pre‐exposure prophylaxis for adolescent girls and young women in Africa: from efficacy trials to delivery
Authors: Celum Connie L , Delany‐Moretlwe Sinead , Baeten Jared M , van der Straten Ariane , Hosek Sybil , Bukusi Elizabeth A , McConnell Margaret , Barnabas Ruanne V , Bekker Linda‐Gail
Published: July 2019

Introduction

Adolescent girls and young women (AGYW) in Africa have high HIV incidence despite scale‐up of HIV testing and HIV treatment. Placebo‐controlled trials of tenofovir‐based pre‐exposure prophylaxi (PrEP) in diverse populations demonstrated that PrEP works with close to 100% effectiveness if taken with high, but not perfect, adherence. Divergent efficacy estimates among African AGYW led to demonstration and implementation projects to better understand motivations for HIV prevention, uptake, adherence and persistence to PrEP. To inform PrEP programmes, the design and initial findings from PrEP demonstration projects for AGYW are reviewed.

Discussion

Early lessons from PrEP implementation projects among young African women include: (1) awareness and demand creation with positive messaging about the benefits of PrEP are critical to motivate AGYW to consider this novel prevention technology and to foster awareness among peers, partners, parents and guardians to support AGYW's effective PrEP use; (2) PrEP initiation is high in projects that are integrating PrEP into youth‐friendly clinics, family planning clinics and mobile clinics; (3) young African women at risk are initiating PrEP, based on behavioural characteristics, history of intimate partner violence, depression and 30% prevalence of chlamydia and/or gonorrhoea; (4) provision of youth‐friendly PrEP delivery programmes that integrate reproductive health services, including contraception and the diagnosis and treatment of sexually transmitted infections, increase health impact; (5) messages that emphasize the necessity for high adherence while at potential risk of HIV exposure and support strategies that addresses AGYW's adherence challenges are essential; and, (6) a substantial proportion of AGYW do not persist with PrEP, and strategies are needed to help AGYW assess their ongoing need, motivation and challenges with persisting with PrEP.

Conclusions

PrEP is feasible to implement in integrated reproductive health service delivery models to reach African AGYW. While PrEP demonstration projects indicate that women with behavioural risks and high rates of sexually transmitted diseases are initiating PrEP; effective strategies to support AGYW's adherence and persistence with PrEP are needed. Lessons learned from oral PrEP delivery, a novel first generation HIV prevention product, are relevant to longer‐acting and less adherence‐dependent strategies which are currently in clinical trials.
The effectiveness of demand creation interventions for voluntary male medical circumcision for HIV prevention in sub‐Saharan Africa: a mixed methods systematic review
Authors: Ensor Samuel , Davies Bethan , Rai Tanvi , Ward Helen
Published: July 2019

Introduction

UNAIDS has recommended that in 14 countries across sub‐Saharan Africa (SSA), 90% of men aged 10 to 29 years should be circumcised by 2021 to help reduce transmission of HIV. To achieve this target demand creation programmes have been widely implemented to increase demand for Voluntary Medical Male Circumcision (VMMC). This review explores the effectiveness of demand creation interventions and factors affecting programme implementation.

Methods

We completed a mixed methods systematic review searching Medline, Embase, Global health, psycINFO and CINAHL databases in August 2018 with no time restrictions. Demand creation interventions conducted in SSA were categorized and quantitative data about VMMC uptake was used to compare relative and absolute effectiveness of interventions. Qualitative data were summarized into themes relevant to the delivery and impact of programmes.

Results and discussion

Eighteen of the 904 titles were included in the review. Effective interventions were identified in each demand creation category: financial incentives, counselling or education, involvement of influencers and novel information delivery. Of the 11 randomized controlled trials (RCTs), the greatest absolute impact on VMMC prevalence was seen with a complex intervention including VMMC promotion training for religious leaders (compared to control: 23% (95% CI 22.8 to 23.8) absolute increase; odds ratio (OR) 3.2 (1.4 to 7.3)). Financial incentives generally produced the largest relative effects with men up to seven‐times more likely to undergo VMMC in the intervention arm compared to control (adjusted OR 7.1 (95% CI 2.4 to 20.8), 7.1% (3.7 to 10.5) absolute increase). Qualitative findings suggest that interventions are more impactful when they are judged appropriate and acceptable by the target population; delivered by people with relevant personal experience; and addressing broader social and cultural influences through partnership with and education of community leaders.

Conclusions

A range of demand creation interventions can increase VMMC uptake. The most acceptable and effective interventions are financial incentives framed as fair compensation (relative effect) and programmes of education or counselling delivered by people who are influential in the community (absolute effect). Future research should include larger studies with longer follow‐up and a consistent definition of VMMC uptake.
Understanding user perspectives of and preferences for oral PrEPforHIVprevention in the context of intervention scale‐up: a synthesis of evidence from sub‐Saharan Africa
Authors: Eakle Robyn , Weatherburn Peter , Bourne Adam
Published: July 2019

Introduction

Oral pre‐exposure prophylaxis (PrEP) forHIVprevention has been proven to significantly reduce newHIVinfections yet scale‐up has been slow. As contexts continue to adjust to make space for PrEP, it is crucial to understand the perspectives and experiences of potential end‐users. In order to inform PrEPand demand creation interventions, this paper examines personal perspectives on adopting and using PrEPamongHIVat‐risk populations in sub‐Saharan Africa.

Methods

Using the principles of a scoping review in July 2018, we explored the extent, range, and nature of published literature regarding PrEPuptake and use among; men who have sex with men,HIVserodiscordant couples, adolescent girls and young women, pregnant and breastfeeding women, women partners of migrant workers; and people who use drugs. Steps included: identification of the research question; identification of relevant studies; study selection; charting the data; and collation – summarizing and reporting results. PubMed and PsycInfo were searched for papers relating to PrEPuptake and use in sub‐Saharan Africa. Resulting papers were reviewed with data extracted and compiled in Excel for analysis. A broad content analysis was conducted and organized into high‐level themes.

Results and discussion

Thirty‐five papers were included in this review. There was little opposition in general to oral PrEP; however, there were significant nuances in its broader acceptability, applicability, and usability. We identified five themes within which these are discussed. These relate to balancing complexities of personal empowerment and stigma; navigating complex risk environments; influences of relationships and partners; efficacy and side effects; and practicalities of use. This body of research suggests that while product attributes and the logistics of PrEPdelivery and use are important topics, it is vital to consider stigma, the interactions of PrEPuse with relationships, and the need for broader understanding ofARVs for prevention versus treatment.

Conclusions

Planning for, programming and promoting the adoption of oral PrEPnecessitates a deeper understanding of end‐user priorities in order to ensure successful interventions. This review illustrates the nuances facilitating or deterring PrEPuse that may affect the larger effort of PrEPscale‐up.
Application of the HIV prevention cascade to identify, develop and evaluate interventions to improve use of prevention methods: examples from a study in east Zimbabwe
Authors: Moorhouse Louisa , Schaefer Robin , Thomas Ranjeeta , Nyamukapa Constance , Skovdal Morten , Hallett Timothy B , Gregson Simon
Published: July 2019

Introduction

The HIV prevention cascade could be used in developing interventions to strengthen implementation of efficacious HIV prevention methods, but its practical utility needs to be demonstrated. We propose a standardized approach to using the cascade to guide identification and evaluation of interventions and demonstrate its feasibility for this purpose through a project to develop interventions to improve HIV prevention methods use by adolescent girls and young women (AGYW) and potential male partners in east Zimbabwe.

Discussion

We propose a six‐step approach to using a published generic HIV prevention cascade formulation to develop interventions to increase motivation to use, access to and effective use of an HIV prevention method. These steps are as follows: (1) measure the HIV prevention cascade for the chosen population and method; (2) identify gaps in the cascade; (3) identify explanatory factors (barriers) contributing to observed gaps; (4) review literature to identify relevant theoretical frameworks and interventions; (5) tailor interventions to the local context; and (6) implement and evaluate the interventions using the cascade steps and explanatory factors as outcome indicators in the evaluation design. In the Zimbabwe example, steps 1‐5 aided development of four interventions to overcome barriers to effective use of pre‐exposure prophylaxis (PrEP) in AGYW (15‐24 years) and voluntary medical male circumcision in male partners (15‐29). For young men, prevention cascade analyses identified gaps in motivation and access as barriers to voluntary medical male circumcision uptake, so an intervention was designed including financial incentives and an education session. For AGYW, gaps in motivation (particularly lack of risk perception) and access were identified as barriers to PrEP uptake: an interactive counselling game was developed addressing these barriers. A text messaging intervention was developed to improve PrEP adherence among AGYW, addressing reasons underlying lack of effective PrEP use through improving the capacity (“skills”) to take PrEP effectively. A community‐led intervention (community conversations) was developed addressing community‐level factors underlying gaps in motivation, access and effective use. These interventions are being evaluated currently using outcomes from the HIV prevention cascade (step 6).

Conclusions

The prevention cascade can guide development and evaluation of interventions to strengthen implementation of HIV prevention methods by following the proposed process.
HIV prevention programme cascades: insights from HIV programme monitoring for female sex workers in Kenya
Authors: Bhattacharjee Parinita , Musyoki Helgar K , Becker Marissa , Musimbi Janet , Kaosa Shem , Kioko Japheth , Mishra Sharmistha , Isac Shajy K , Moses Stephen , Blanchard James F
Published: July 2019

Introduction

HIV prevention cascades have emerged as a programme management and monitoring tool that outlines the sequential steps of an HIV prevention programme. We describe the application of an HIV combination prevention programme cascade framework to monitor and improve HIV prevention interventions for female sex workers (FSWs) in Kenya.

Methods

Two data sources were analysed: (1) annual programme outcome surveys conducted using a polling booth survey methodology in 2017 among 4393 FSWs, and (2) routine programme monitoring data collected by (a) 92 implementing partners between July 2017 and June 2018, and (b) Learning Site in Mombasa (2014 to 2015) and Nairobi (2013). We present national, sub‐national and implementing partner level cascades.

Results

At the national level, the population size estimates for FSW were 133,675 while the programme coverage targets were 174,073. Programme targets as denominator, during the period 2017 to 2018, 156,220 (90%) FSWs received peer education and contact, 148,713 (85%) received condoms and 83,053 (48%) received condoms as per their estimated need. At the outcome level, 92% of FSWs used condoms at the last sex with their client but 73% reported consistent condom use. Although 96% of FSWs had ever tested for HIV, 85% had tested in the last three months. Seventy‐nine per cent of the HIV‐positive FSWs were enrolled in HIV care, 73% were currently enrolled on antiretroviral therapy (ART) and 52% had attended an ART clinic in the last month. In the last six months, 48% of the FSWs had experienced police violence but 24% received violence support. National and sub‐national level cascades showed proportions of FSWs lost at each step of programme implementation and variability in programme achievement. Hotspot and sub‐population level cascades, presented as examples, demonstrate development and use of these cascades at the implementation level.

Conclusions

HIV prevention programme cascades, drawing on multiple data sources to provide an understanding of gaps in programme outputs and outcomes, can provide powerful information for monitoring and improving HIV prevention programmes for FSWs at all levels of implementation and decision‐making. Complexity of prevention programmes and the paucity of consistent data can pose a challenge to development of these cascades.
A longitudinal study of associations between HIV‐related stigma, recent violence and depression among women living with HIV in a Canadian cohort study
Authors: Logie Carmen H , Marcus Natania , Wang Ying , Kaida Angela , O'Campo Patricia , Ahmed Uzma , O'Brien Nadia , Nicholson Valerie , Conway Tracey , de Pokomandy Alexandra , Fernet Mylène , Loutfy Mona ,   the CHIWOS Research Team
Published: July 2019

Introduction

Women living with HIV (WLHIV) experience stigma and elevated exposure to violence in comparison with HIV‐negative women. We examined the mediating role of experiencing recent violence in the relationship between stigma and depression among WLHIV in Canada.

Methods

We conducted a cohort study with WLHIV in three Canadian provinces. Recent violence was assessed through self‐reported experiences of control, physical, sexual or verbal abuse in the past three months. At Time 1 (2013‐2015) three forms of stigma were assessed (HIV‐related, racial, gender) and at Time 2 (2015‐2017) only HIV‐related stigma was assessed. We conducted structural equation modelling (SEM) using the maximum likelihood estimation method with Time 1 data to identify direct and indirect effects of gender discrimination, racial discrimination and HIV‐related stigma on depression via recent violence. We then conducted mixed effects regression and SEM using Time 1 and Time 2 data to examine associations between HIV‐related stigma, recent violence and depression.

Results

At Time 1 (n = 1296), the direct path from HIV‐related stigma (direct effect: β = 0.200, p < 0.001; indirect effect: β = 0.014, p < 0.05) to depression was significant; recent violence accounted for 6.5% of the total effect. Gender discrimination had a significant direct and indirect effect on depression (direct effect: β = 0.167, p < 0.001; indirect effect: β = 0.050, p < 0.001); recent violence explained 23.15% of the total effect. Including Time 1 and Time 2 data (n = 1161), mixed‐effects regression results indicate a positive relationship over time between HIV‐related stigma and depression (Acoef: 0.04, 95% CI: 0.03, 0.06, p < 0.001), and recent violence and depression (Acoef: 1.95, 95% CI: 0.29, 4.42, p < 0.05), controlling for socio‐demographics. There was a significant interaction between HIV‐related stigma and recent violence with depression (Acoef: 0.04, 95% CI: 0.01, 0.07, p < 0.05). SEM analyses reveal that HIV‐related stigma had a significant direct and indirect effect on depression over time (direct effect: β = 0.178, p < 0.001; indirect effect: β = 0.040, p < 0.001); recent violence experiences accounted for 51% of the total effect.

Conclusions

Our findings suggest that HIV‐related stigma is associated with increased experiences of recent violence, and both stigma and violence are associated with increased depression among WLHIV in Canada. There is an urgent need for trauma‐informed stigma interventions to address stigma, discrimination and violence.
Phenotypic impacts of CSF1R deficiencies in humans and model organisms
Authors: Hume David A. , Caruso Melanie , Ferrari-Cestari Michelle , Summers Kim M. , Pridans Clare , Irvine Katharine M.
Published: July 2019

Mϕ proliferation, differentiation, and survival are controlled by signals from the Mϕ CSF receptor (CSF1R). Mono-allelic gain-of-function mutations in CSF1R in humans are associated with an autosomal-dominant leukodystrophy and bi-allelic loss-of-function mutations with recessive skeletal dysplasia, brain disorders, and developmental anomalies. Most of the phenotypes observed in these human disease states are also observed in mice and rats with loss-of-function mutations in Csf1r or in Csf1 encoding one of its two ligands. Studies in rodent models also highlight the importance of genetic background and likely epistatic interactions between Csf1r and other loci. The impacts of Csf1r mutations on the brain are usually attributed solely to direct impacts on microglial number and function. However, analysis of hypomorphic Csf1r mutants in mice and several other lines of evidence suggest that primary hydrocephalus and loss of the physiological functions of Mϕs in the periphery contribute to the development of brain pathology. In this review, we outline the evidence that CSF1R is expressed exclusively in mononuclear phagocytes and explore the mechanisms linking CSF1R mutations to pleiotropic impacts on postnatal growth and development.
Multiplex polymerase chain reaction detection of Curvularia lunata, Bipolaris maydis, and Aureobasidium zeae in infected maize leaf tissues
Authors: Lu Yuanyuan , Song Yanbo , Xue Zhiquan
Published: July 2019

Multiplex polymerase chain reaction (PCR) is a method for simultaneous identification and detection of multiple pathogenic fungi, however, its complexity limits its application. To simplify the protocol and to improve the effectiveness, three‐level designs for six factors (three primers, Taq DNA polymerase, dNTP, Mg2+) were constructed to optimize the multiplex PCR system by using the orthogonal design method and the annealing temperature of the PCR reactions was also optimized. Finally, a multiplex PCR system for the simultaneous detection of these three pathogens of maize was successfully established. The reaction volume was 25 μl and the annealing temperature was 57℃. The optimal conditions for multiplex PCR reaction contained 0.48 μmol/L Cl‐1/Cl‐2, 0.72 μmol/L Bm‐1/Bm‐2, 0.24 μmol/L Az‐1/Az‐2, 1.5 U polymerase, 0.35 mmol/L dNTP, and 1.25 mmol/L MgCl2. The multiplex PCR system can detect Curvularia lunata, Bipolaris maydis, and Aureobasidium zeae in infected plant tissues rapidly with the sensitivity at 10 pg DNA/μl.
Dominant modes of interannual variability of extreme high‐temperature events in eastern China during summer and associated mechanisms
Authors: Zhu Baoyan , Sun Bo , Wang Huijun
Published: July 2019

This study investigated the interannual variability of the frequency of extreme high‐temperature events (FEHE) during summer over eastern China and associated mechanisms. Two leading modes of interannual variability of FEHE over eastern China during summer are obtained by Empirical Orthogonal Function (EOF) analysis. The first EOF (EOF1) mode of FEHE shows a diploe pattern characterized by positive (negative) anomalies in northeastern (southern) China. The second EOF (EOF2) mode of FEHE shows a monopole pattern characterized by positive anomalies in the Yangtze River valley (YRV) region. The potential mechanisms of the two leading modes are different. The EOF1 of FEHE is modulated by the EOF1 of 500‐hPa geopotential height (Z500) over Eurasia, which exhibits a Eurasian wave train associated with the air–sea interaction over the North Atlantic. Besides, anomalous SSTs over the western tropical Pacific and associated anomalous convective activity over the Maritime continent may also exert an impact on the EOF1 of FEHE via stimulating a meridional wave train, the so‐called “Pacific‐Japan/East Asia‐Pacific” teleconnection. The EOF2 of FEHE is mainly associated with the NAO mode.
Prevalence of peri‐implant diseases among an Italian population of patients with metabolic syndrome: A cross‐sectional study
Authors: Papi Piero , Di Murro Bianca , Pranno Nicola , Bisogni Valeria , Saracino Vincenza , Letizia Claudio , Polimeni Antonella , Pompa Giorgio
Published: July 2019

Background

Over the years, only few authors have studied the association of systemic conditions with peri‐implantitis. The aim of this study is to detect frequency and severity of peri‐implant diseases among an Italian population of patients affected by metabolic syndrome (MetS).

Methods

In this cross‐sectional study, patients with at least one dental implant with >5 years of functional loading were screened to evaluate metabolic, periodontal, and peri‐implant status. MetS diagnosis was established in accordance with the National Cholesterol Education Program (NCEP) ATP III criteria, while case definitions of the 2017 World Workshop were adopted for peri‐implant diseases. For each implant, probing depths, mucosal redness, bleeding on probing, suppuration, plaque index, and marginal bone loss were recorded. Multinomial logistic regression analyzed the relationship between sex, diagnosis of MetS, presence of periodontitis, smoking, type of prosthesis, and location of implants and peri‐implant mucositis and peri‐implantitis.

Results

A total of 183 patients were enrolled: in MetS subjects, peri‐implantitis was detected in 36.9% (n = 31) of implants, and mucositis in 60.7% (n = 51), with an OR of 10.01(P = 0.005) for mucositis and OR 15.26 (P = 0.001) for peri‐implantitis, compared with subjects without MetS, where 26.3% of implants showed peri‐implantitis and 55.5% mucositis. No differences were found for smoking, implant location, sex, and type of prosthetic rehabilitation. Patients with periodontitis showed a higher association with peri‐implant mucositis (OR = 4.33) and peri‐implantitis (OR = 9.00).

Conclusion

Based on the results of this study, patients affected by MetS showed a greater prevalence of peri‐implant diseases, but further studies are needed to confirm the possibility of this new possible risk indicator.
Effects of zinc methionine supplementation on laying performance, zinc status, intestinal morphology, and expressions of zinc transporters' mRNA in laying hens
Authors: Li Lanlan , Li Huaiyu , Zhou Wenting , Feng Jie , Zou Xiaoting
Published: July 2019

BACKGROUND

This study was conducted to investigate effects of dietary zinc methionine (Zn‐Met) supplementation on laying performance, zinc (Zn) status, intestinal morphology, and Zn transporters in laying hens compared with zinc sulfate (ZnSO4). A total of 384 Hyline Grey laying hens (38 weeks old) with similar performance (1.42 ± 0.07 kg) were randomly allotted to four dietary treatments and fed with a basal diet (control) or the basal diet supplemented with Zn, either as Zn‐Met at 40 and 80 mg Zn/kilogram diet or as ZnSO4 at 80 mg Zn/kilogram diet, for 10 weeks.

RESULTS

There was no difference in egg weight, egg production, feed intake, and feed conversation ratio among all groups (P > 0.05). Compared with the control, Zn contents were increased (P < 0.05) in the liver, duodenum, and jejunum of laying hens fed diets supplemented with different Zn sources. There was no difference (P > 0.05) in Zn contents in liver, duodenum, and jejunum between diets supplemented with Zn‐Met or ZnSO4 at 80 mg Zn/kilogram diet. Compared with the control and the ZnSO4 group (80 mg Zn/kilogram diet), supplementation with Zn‐Met of 80 mg Zn/kilogram diet increased (P < 0.05) villus height, villus area, and villus height/crypt depth ratio but reduced (P < 0.05) crypt depth in jejunum. Expression of metallothionein messenger RNA of jejunum in the group fed a diet containing Zn‐Met (80 mg Zn/kilogram diet) was higher (P < 0.05) than that in the control.

CONCLUSION

These results indicated that Zn‐Met has positive effects on the Zn status of liver, duodenum, and jejunum, intestinal morphology, and metallothionein messenger RNA expression in jejunum of laying hens compared with ZnSO4. © 2019 Society of Chemical Industry
Rapid detection of rice disease using microscopy image identification based on the synergistic judgment of texture and shape features and decision tree–confusion matrix method
Authors: Yang Ning , Qian Yong , EL‐Mesery Hany S , Zhang Rongbiao , Wang Aiying , Tang Jian
Published: July 2019

BACKGROUND

Rice smut and rice blast are listed as two of the three major diseases of rice. Owing to the small size and similar structure of rice blast and rice smut spores, traditional microscopic methods are troublesome to detect them. Therefore, this paper uses microscopy image identification based on the synergistic judgment of texture and shape features and the decision tree–confusion matrix method.

RESULTS

The distance transformation–Gaussian filtering–watershed algorithm method was proposed to separate the adherent rice blast spores, and the accuracy was increased by about 10%. Four shape features (area, perimeter, ellipticity, complexity) and three texture features (entropy, homogeneity, contrast) were selected for decision‐tree model classification. The confusion‐matrix algorithm was used to calculate the classification accuracy, in which global accuracy is 82% and the Kappa coefficient is 0.81. At the same time, the detection accuracy is as high as 94%.

CONCLUSIONS

The synergistic judgment of texture and shape features and the decision tree–confusion matrix method can be used to detect rice disease quickly and precisely. The proposed method can be combined with a spore trap, which is vital to devise strategies early and to control rice disease effectively. © 2019 Society of Chemical Industry
Polymer phase transition characteristics coupled with GC‐MS for the determination of phthalate esters
Authors: Chen Xiaomei , Xin Ladi , Xu Yidong , Liu Jie , Li Zhiqiang , Wang Yi , Zhao Jingchan
Published: July 2019

Phthalate esters are easily released from plastics materials and migrate into the soil and water environment, causing serious pollution and posing a great threat to the health of human beings. A novel temperature‐sensitive extractant combined with liquid–liquid microextraction was developed to preconcentrate three phthalates in the water environment. To optimize the extraction efficiency for the three phthalate esters, various parameters, including polymer molecular weight, salt type, salt addition, adsorption time, desorption solvent, desorption volume, and desorption time have been studied. Under optimal conditions, limits of detection and limits of quantification were in the range of 0.007–0.120 and 0.021–0.350 µg/L, respectively. Linearities varied in the range of 5–1000 µg/L, with the correlation coefficients of 0.9867–0.9997. The preconcentration factors were in the range of 25–75. The relative recoveries of the three phthalate esters were in the range of 82.2–105.6% at the spiked levels. The relative standard deviations were in the range of 0.7–9.2% based on triplicate measurements. The results indicate that the temperature‐sensitive material is a good extractant for phthalate esters in water samples.
Tourist value orientations and conflicts at a marine protected area in Hawaii
Authors: Philips Li P. , Szuster Brian W. , Needham Mark D.
Published: July 2019

Marine tourism is increasing in popularity, which may cause conflicts among tourists who value different aspects of settings and experiences. Visitors surveyed before and after tours to Molokini Shoal Marine Life Conservation District in Hawaii (USA) reported considerable (63%) in‐group conflicts (bump into people and rude or discourteous) between snorkelers and other snorkelers. One third of scuba divers experienced conflicts with other divers. Most conflicts were interpersonal (interactions between individuals interfering with experiences). There were fewer out‐group conflicts between snorkelers and divers (15–28%) and minimal social values conflicts (6–13%; negative preconceptions without interactions). Many visitors had strong biocentric and protectionist value orientations toward the environment and coral reefs, and these individuals were most likely to report conflicts.
Drivers of soil carbon stabilization in oil palm plantations
Authors: Rüegg Johanna , Quezada Juan Carlos , Santonja Mathieu , Ghazoul Jaboury , Kuzyakov Yakov , Buttler Alexandre , Guillaume Thomas
Published: July 2019

Increasing soil organic carbon (SOC) in agroecosystems is necessary to mitigate climate change and soil degradation. Management practices designed to reach this goal call for a deeper understanding of the processes and drivers of soil carbon input stabilization. We identified main drivers of SOC stabilization in oil palm plantations using the well‐defined spatial patterns of nutrients and litter application resulting from the usual management scheme. The stabilization of oil palm‐derived SOC (OP‐SOC) was quantified by δ13C from a shift of C4 (savanna) to C3 (oil palm) vegetations. Soil organic carbon stocks under frond piles were 20% and 22% higher compared with harvest paths and interzones, respectively. Fertilization and frond stacking did not influence the decomposition of savanna‐derived SOC. Depending on management zones, net OP‐SOC stabilization equalled 16–27% of the fine root biomass accumulated for 9 years. This fraction was similar between frond piles and litter‐free interzones, where mineral NPK fertilization is identical, indicating that carbon inputs from dead fronds did not stabilize in SOC. A path analysis confirmed that the OP‐SOC distribution was largely explained by the distribution of oil palm fine roots, which itself depended on management practices. SOC mineralization was proportional to SOC content and was independent on phosphorus availability. We conclude that SOC stabilization was driven by C inputs from fine roots and was independent of alteration of SOC mineralization due to management. Practices favouring root growth of oil palms would increase carbon sequestration in soils without necessarily relying on the limited supply of organic residues.
Genomic adaptation of marine phytoplankton populations regulates phosphate uptake
Authors: Martiny Adam C. , Ustick Lucas , A. Garcia Catherine , Lomas Michael W.
Published: July 2019

In this study, we combined “reciprocal transplant experiments,” cell‐sorting, and metagenomics to understand how phytoplankton adapt to differences in phosphate availability and the implications for nutrient uptake rates. Reciprocal transplant experiments were conducted on six stations ranging from cold, nutrient‐rich water in the Labrador Sea to warm, extremely P‐deplete water in the Sargasso Sea. In most cases, the direct impact of environmental conditions and likely P availability was the strongest control on phosphate uptake. However, especially the transplant experiments between the northern and southern stations revealed that there are situations where changes in community composition and functional genes have an important effect on uptake rates. Phytoplankton lineages responded uniquely to changing environmental conditions. The picoeukaryotic phytoplankton P uptake response was strongly regulated by the phosphate concentration, whereas the effect of community composition was larger for Prochlorococcus and Synechococcus. In support, we found a tight negative relationship between ambient phosphate concentration and the frequency of P acquisition genes in both Prochlorococcus and Synechococcus, and such differences in genome content could be linked to lineage‐specific shifts in uptake rates. Linking genes with ocean biogeochemistry is a major scientific and technical challenge and most studies rely on correlations between genotypes and environmental conditions. However, our study demonstrates how reciprocal transplant experiments are a possible tool for understanding the relative role of environmental condition vs. plankton diversity in regulating important open ocean ecosystem processes.
Modifying the Properties of Thermogelling Poloxamer 407 Solutions through Covalent Modification and the Use of Polymer Additives
Authors: Abou‐Shamat Mohamad A. , Calvo‐Castro Jesus , Stair Jacqueline L. , Cook Michael T.
Published: July 2019

Thermoresponsive polymers that undergo sol–gel transition in a physiological temperature range have applications in biomedical science. Poloxamer 407 (P407) is commonly used as thermogelling material and has been approved by the Food and Drug Administration (FDA) in licenced medicines. However, it has significant drawbacks which limit its performance, particularly in drug delivery systems. In order to improve these properties, the chemical structure of P407 has been modified to produce stronger gels by either conjugating P407 with other polymers or introducing inter‐micelle linkers to the terminal hydroxyl groups of P407. However, chemical modifications have several undesirable side‐effects. The change in the chemical structure makes the polymer a novel excipient, and additional safety risks are possible, requiring expensive and time‐consuming toxicity testing prior to regulatory approval. An alternative approach to covalent modification is modifying the P407 formulations with additives including hydrophilic polymers and nanoparticles, in an attempt to improve the properties of these materials. This review investigates the approaches used to modify the properties of P407 thermogelling materials, including the use of polymer additives and covalent modification. Several recommendations are made, based on efficacy and consideration of regulatory risk to guide the development of these materials toward use in real clinical applications.
A Study of Finite Size Effects and Periodic Boundary Conditions to Simulations of a Novel Theoretical Self‐Consistent Mean‐Field Approach
Authors: Yang Guanda , Nilsson Fritjof , Schubert Dirk W.
Published: July 2019

In a previous work, a very promising mathematical model for predicting the electrical conductivity below the electrical percolation threshold, for both isotropic and anisotropic composites, was published by Schubert. In this work, periodic boundary condition of the simulation is utilized. The results are also compared to the previous work and other theoretical models. The truncated fibers due to finite size of the simulation volume are considered as two individual pieces so that the real aspect ratios will also be taken into consideration. A comparison is made between two groups, in which the length and the radius of the carbon fibers are changed, respectively, under certain aspect ratios. With three different sizes of the simulation volumes, the influence on the results due to the finite size effect is calculated.
Fundamental mechanisms and their interactions in shear‐clinching technology and investigation of the process robustness
Authors: Wiesenmayer S. , Han D. , Müller M. , Hörhold R. , Meschut G. , Merklein M.
Published: July 2019

The compliance with increasingly stricter emission standards is a challenge for the automotive industry, which requires the utilization of lightweight materials e. g. aluminium and high‐strength steels. Hereby, the load‐optimized design of body parts and the reduction of wall thicknesses are enabled. But, due to the use of dissimilar materials, common joining technologies are reaching their limits. On the one hand, joining by welding is often not possible because of different melting temperatures. On the other hand, joining by forming with additional fasteners increases the cycle time and the costs. However, joining by forming without fasteners is often limited by the mechanical properties of the joining partners. The innovative shear‐clinching technology combines shear‐cutting and clinching in a single stage process and thereby enables joining by forming of materials with high differences regarding their mechanical properties. However, by the combination of the sub‐processes cutting and joining, the complexity of the technology is increased. Thus, within the scope of this work, the fundamental mechanisms in shear‐clinching and their interactions as well as the robustness of the process are analysed, in order to promote the applicability of the technology.
Differential regulation of mycelial growth and aflatoxin biosynthesis by Aspergillus flavus under different temperatures as revealed by strand‐specific RNA‐Seq
Authors: Han Guomin , Zhao Kai , Yan Xiaodan , Xiang Fangzhi , Li Xuede , Tao Fang
Published: July 2019

Although several regulatory pathways have been reported for Aspergillus flavus, the regulation of aflatoxin production and mycelial growth under different temperatures remains unclear. In this study, A. flavus differentially expressed genes (DEGs) and regulatory pathways were analyzed under three temperatures, by strand‐specific RNA‐Seq. Results show that a total of 2,428 and 1,474 DEGs were identified in fungal mycelia cultured at 20°C and 37°C, respectively, as compared with the control (28°C). Approximately ~ 79% of DEGs in the 37°C samples were up‐regulated genes, while ~ 63% of DEGs in the 20°C samples were down‐regulated genes. Most of the DEG pathways enriched by lower temperatures differed from those enriched by higher temperatures, while only a small portion of the pathways were shared by A. flavus grown under different temperatures. Aflatoxin biosynthesis, Butanoate metabolism, oxidation–reduction process, and benzene‐containing compound metabolic process were the shared down‐regulated pathways, while steroid biosynthesis, oxidoreductase activity, cellular protein modification process, DNA binding, protein complex were the shared up‐regulated pathways between lower and higher temperatures. The shared genes and pathways are the key regulatory candidates for aflatoxin biosynthesis with changes of temperature. In addition, the identification of both up‐regulated and down‐regulated genes provides a useful gene set for further investigation of the aflatoxin biosynthesis among Aspergillus.
A method using the cephalic vein for superdrainage in breast reconstruction
Authors: Tokumoto Hideki , Akita Shinsuke , Arai Minami , Kubota Yoshitaka , Kuriyama Motone , Mitsukawa Nobuyuki
Published: July 2019

Background

In breast reconstruction, a superdrainage procedure using the superficial inferior epigastric vein has been described. The purpose of this study was to investigate whether the utility of cephalic vein (CV) was equivalent to that of serratus anterior muscle branch of the thoracodorsal vein (SA) and lateral thoracic vein (LTV) for recipient vein.

Methods

Eighty‐eight patients were enrolled in this study. The superdrainage was not performed if the internal mammary vein diameter was greater than, or equal to, that of the deep inferior epigastric vein diameter. In superdrainage cases, the SA or LTV was used as the recipient vein firstly, and the CV was used when both of them were unsuitable.

Results

The superdrainage was performed in 45 (51.1%) patients. No significant differences were observed between with and without superdrainage. In superdrainage group, the CV was used in 7 (15.5%) patients. In two groups (CV vs. LTV and SA), because we added to perform superdrainage to the CV at the time of re‐exploration and tried to use the SA or the LTV firstly, the re‐exploration rate (28.6 vs. 0%) and operating time (652.1 vs. 591.1 min) of CV group were significantly high (p = .023 and .028). No complications were observed, due to CV harvesting. Other characteristics showed no significant differences.

Conclusions

At the point of superdrainage, the CV was equivalent to the SA and LTV. Using of the CV would only be essential in rare cases; nonetheless, the possibility of its use should be considered.
Highly efficient differential rectenna for RF energy harvesting
Authors: Chang Yumei , Zhang Peng , Wang Lin
Published: July 2019

A highly efficient balanced rectenna is proposed in this work. To decrease the sensitive input power density of the rectenna, a rectifying circuit with balanced bandpass filter connects the dipole to the diodes. Using this technique, the proposed rectenna can capture incident RF signal with low power density, that is, when the incident power density Pin is 2 mW, the RF‐DC conversion efficiency for our design at 2.45 GHz can remain above 20%, while the best performance happens at Pin = 18.5 dBm, which can reach up to 72.3% in simulations. To verify our proposal, a sample is fabricated and measured, and the measured RF‐DC conversion efficiency can reach up to 50% or so when the captured power on the dipole is about 17 dBm and the load resistor is 350 Ω.
HYDRA: Hybrid deep magnetic resonance fingerprinting
Authors: Song Pingfan , Eldar Yonina C. , Mazor Gal , Rodrigues Miguel R. D.
Published: July 2019

Purpose

Magnetic resonance fingerprinting (MRF) methods typically rely on dictionary matching to map the temporal MRF signals to quantitative tissue parameters. Such approaches suffer from inherent discretization errors, as well as high computational complexity as the dictionary size grows. To alleviate these issues, we propose a HYbrid Deep magnetic ResonAnce fingerprinting (HYDRA) approach, referred to as HYDRA.

Methods

HYDRA involves two stages: a model‐based signature restoration phase and a learning‐based parameter restoration phase. Signal restoration is implemented using low‐rank based de‐aliasing techniques while parameter restoration is performed using a deep nonlocal residual convolutional neural network. The designed network is trained on synthesized MRF data simulated with the Bloch equations and fast imaging with steady‐state precession (FISP) sequences. In test mode, it takes a temporal MRF signal as input and produces the corresponding tissue parameters.

Results

We validated our approach on both synthetic data and anatomical data generated from a healthy subject. The results demonstrate that, in contrast to conventional dictionary matching‐based MRF techniques, our approach significantly improves inference speed by eliminating the time‐consuming dictionary matching operation, and alleviates discretization errors by outputting continuous‐valued parameters. We further avoid the need to store a large dictionary, thus reducing memory requirements.

Conclusions

Our approach demonstrates advantages in terms of inference speed, accuracy, and storage requirements over competing MRF methods.
Magnetic Resonance Elastography of kidneys: SE‐EPI MRE reproducibility and its comparison to GRE MRE
Authors: Gandhi Deep , Kalra Prateek , Raterman Brian , Mo Xiaokui , Dong Huiming , Kolipaka Arunark
Published: July 2019

The purpose of this study is 1) to demonstrate reproducibility of spin echo‐echo planar imaging (SE‐EPI) magnetic resonance elastography (MRE) to estimate kidney stiffness; and 2) to compare SE‐EPI MRE and gradient recalled echo (GRE) MRE‐derived stiffness estimations in various anatomical regions of the kidney.

Kidney MRE was performed on 33 healthy subjects (8 for SE‐EPI MRE reproducibility and 25 for comparison with GRE MRE; age range: 22–66 years) in a 3 T MRI scanner. To demonstrate SE‐EPI MRE reproducibility, subjects were scanned for the first scan and then asked to leave the scan room and repositioned again for the second (repeat) scan. Similar set‐up was used for GRE MRE as well. The displacement data was then processed to obtain overall stiffness estimates of the kidney. Concordance correlation analyses were performed to determine SE‐EPI MRE reproducibility and agreement between GRE MRE and SE‐EPI MRE derived stiffness.

A high concordance correlation (ρc = 0.95; p‐value<0.0001) was obtained for SE‐EPI MRE reproducibility. Good concordance correlation was observed (ρc = 0.84; p < 0.0001 for both kidneys, ρc = 0.91; p < 0.0001 for right kidney and ρc = 0.78; p < 0.0001 for left kidney) between GRE MRE and SE‐EPI MRE derived stiffness measurements. Paired t‐test results showed that stiffness value of medulla was significantly (p < 0.0001) greater than cortex using SE‐EPI MRE as well as GRE MRE.

SE‐EPI MRE was reproducible and good agreement was observed in MRE‐derived stiffness measurements obtained using SE‐EPI and GRE sequences. Therefore, SE‐EPI can be used for kidney MRE applications.
β3‐Adrenergic Activation Improves Maternal and Offspring Perinatal Outcomes in Diet‐Induced Prepregnancy Obesity in Mice
Authors: Zhang Jun‐Kai , Miao Jun , Chen Zu‐Qin , Duan Si‐Zhang , Zhang Xin , Ji Wen‐Jie , Niu Jian‐Min , Yuan Fei , Zhou Xin , Li Yu‐Ming , Zhang Zhuoli
Published: July 2019

Objective

Prepregnancy obesity is an epidemic disorder that seriously threatens both maternal and offspring health. This study investigated the effects of β3‐adrenergic receptor (β3‐AR) activation on the perinatal outcomes in a diet‐induced prepregnancy obese (PPO) murine model.

Methods

Four‐week‐old female C57BL/6 mice were fed high‐fat diet or chow diet for 16 weeks to yield PPO mice and chow‐fed (CF) lean mice, respectively. After successful mating with CF males, the PPO and CF mice were both randomly divided into vehicle control‐ or CL316,243 (a highly selective β3‐AR agonist)‐treated groups. On gestational day 7, subcutaneous infusion of CL316,243 or saline vehicle (1 mg/kg/d) was provided using osmotic pumps. The perinatal outcomes, adipose tissue morphology, and metabolic and inflammatory markers were examined.

Results

Chronic β3‐AR agonist infusion induced brown adipose tissue activation and white adipose tissue browning and countered obesity‐induced alterations in lipid profiles, insulin resistance, and systemic and local inflammatory states. Moreover, β3‐AR activation was associated with improved placental perfusion and offspring outcomes.

Conclusions

Our results provide proof‐of‐principle evidence that pharmacological β3‐AR activation may be of therapeutic potential in preventing prepregnancy‐obesity‐associated adverse maternal and offspring perinatal outcomes.
Preparation and characterization of phosphorylated graphene oxide grafted with poly(L‐lactide) and its effect on the crystallization, rheological behavior, and performance of poly (lactic acid)
Authors: Yang Li , Zhen Weijun
Published: July 2019

Phosphorylated graphene oxide (PGO) was prepared by using phosphoric acid as functional reagent, and PGO was grafted with poly(L‐lactide) (PGO‐PLLA) by ring‐opening polymerization of L‐lactide as monomer under nano‐ZnO catalyst. The results of the orthogonal analysis showed the optimum reaction conditions to be as follows: the reaction temperature of 170°C, reaction time of 14 hours, the mass ratio of PGO of 10 wt%, and the mass of nano‐ZnO of 1 wt%. PGO‐PLLA was characterized by fourier transform infrared spectroscopy, gel permeation chromatography, and X‐ray photoelectron spectroscopy, which demonstrated that the PLLA molecular chains were successfully grafted onto the surface of PGO. Poly (lactic acid)/PGO‐PLLA nanocomposites (PLA/PGO‐PLLA) were prepared by melt intercalation. Mechanical test and fracture scanning electron microscopy showed that PGO‐PLLA (0.3 wt%) improved impact strength of PLA by 52.19%, which resulted in ductile fractures surface of PLA/PGO‐PLLA. Microcalorimetry and thermal degradation kinetics proved that PGO‐PLLA improved the thermal stability of PLA. Polarized optical microscopy and differential scanning calorimetry confirmed that PGO‐PLLA increased crystallization rate and spherulite kernel density of PLA, and crystallinity of PLA/PGO‐PLLA reached to 22.05%. Rheological behavior proved that PGO‐PLLA increased the self‐lubricity of PLA. Enzymatic degradation results illustrated that PGO‐PLLA had some inhibition for the biodegradability of PLA based nanocomposites.