bluuebunny/crossref_metadata_2025 huggingface dataset:
Treatments of Micro-channel Flows Revisited: Continuum Versus Rarified Gas Considerations
Authors: Durst F. , Filimonov D. , Sambasivam R.
Published: June 2020

There are numerous treatments of micro-channel flows available that point out the breakdown of the Navier–Stokes equations under molecular flow conditions when continuum conditions should still apply. The wrong conclusion regarding the validity of the Navier–Stokes equations comes about from the missing mass diffusion terms in the continuity equation. This term also affects the Navier–Stokes equations and yields improved theoretical results for flows with strong pressure and temperature gradients. Rarified gas treatments are often applied, although the fluid mechanics conditions are still such, that continuum equations should work. In the paper, the missing mass diffusion term is added, and it is shown that those extended fluid mechanics equation (EFME) allows micro-channel flows to be treated in the so-called slip regime. Hence, the continuum approach for flow treatment holds in micro-channel flows, in the flow regimes where modeling of wall interactions is applied these days. The paper also describes the treatments of micro-channel flows in the slip-flow regime by the rarified gas flow treatment method of Shapiro and Seleznev, and the results are compared with the corresponding results of the EFME. Good agreement was obtained, but differences exist regarding the wall interactions, which are explained, and suggested to use both methods to obtain a deeper insight into molecule–wall interactions in micro-channel flows. The EFME claim that large pressure and temperature gradients are the reasons for the differences between experimental and theoretical results of micro-channel flows. Such differences also exist in other fluid flows with strong property gradients, e.g., in shock waves. Flows of this kind are also treated in this paper in a way to show that the EFME have a wide range of applications.
Development and Benefits of Winch-Assist Harvesting
Authors: Holzfeind Thomas , Visser Rien , Chung Woodam , Holzleitner Franz , Erber Gernot
Published: June 2020

Purpose of Review

Winch-assist systems have seen rapid development, adoption, and implementation in many parts of the world in the past decade and can be considered one of the major recent innovations in steep terrain harvesting. Though a comparatively young topic, the literature around this topic has grown considerably during the last decade. This review summarizes the present body of literature on winch-assist systems and provides a comprehensive introduction to the topic.

Recent Findings

The analysis showed that work safety in steep terrain harvesting operations has increased through winch-assist systems by removing workers from the many hazards of manual and motor-manual work. The extent of rutting, subsequent erosion, and soil densification after working with winch-assist systems was found to be similar to operations on gentle terrain or cable logging. Winch-assist harvesting is considered more productive than conventional steep terrain harvesting. While case studies provide indicative utilization and productivity values, a robust understanding of economic viability under varied stand and terrain conditions is not yet well established.

Winch-assist is proving to be a robust, safe, and high-performance forest harvesting technology that has increased the operating range of ground-based, mechanized harvesting. It can help increase access to forest grounds in steep terrain that are previously considered economically marginal for forest management. Besides steep terrain, the potential benefits of winch-assist in reducing soil disturbance from ground-based equipment indicate that its operating range can also expand to gentle terrain where environmental impacts are of great concern due to wet or unstable soils. As the technology is relatively young and still evolving, there are many unknown social, environmental, and economic challenges and opportunities associated with the winch-assist technology. More research is certainly warranted.
Measuring Well-Being: Trial of the Neighbourhood Thriving Scale for Social Well-Being Among Pro-Social Individuals
Authors: Baldwin Cathy , Vincent Penny , Anderson Jamie , Rawstorne Patrick
Published: June 2020

We report on a trial of theneighbourhood thriving framework(NTF), a conceptual framework from psychology and social science for measuring collective subjective social well-being. It combines the notions of feeling good and functioning effectively in a neighbourhood social environment in an indicator set of 15 conceptual dimensions. An online questionnaire was used to measureneighbourhood thriving(NT) among 212 pro-social volunteers involved in revitalising neighbourhoods in the UK city of Stoke-on-Trent between May and October 2018. Exploratory factor analysis revealed 11 factors that made conceptual sense including three social epidemiological pathways to well-being, networks, participation and pro-social behaviours, and four criteria forflourishingsocieties, autonomous citizenship, safety, cohesive communities and resilience. The 11 sub-scales of NT showed satisfactory internal consistency reliability and preliminary evidence of construct validity. The sub-scales were used tentatively to examine NT among the volunteer sample, which showed the highest sub-scale score forPositive Regardand the lowest score forCelebration. Different levels of NT were observed among the community, with age and income positively associated with higher levels of NT. Further validation work is needed before the NT scales can be used with confidence. Validated scales offer potential benefits including: measuring NT pre- and -post project implementation; establishing which dimensions of NT are, and are not, working well in a community and need strengthening through further initiatives, and establishing which specific groups of people are experiencing lower levels of NT and designing projects that meet their needs.
Optical Theory-Based Simulation of Attenuated Total Reflection Infrared Spectra of Montmorillonite Films
Authors: Grégoire Brian , Dazas Baptiste , Leloup Maud , Hubert Fabien , Tertre Emmanuel , Ferrage Eric , Petit Sabine
Published: June 2020

Infrared analyses of clay mineral samples are usually performed by transmission techniques. While transmission measurements are easy and inexpensive, the sample preparation plays a critical role in the quality of the data. Alternatively, attenuated total reflection (ATR) provides a powerful and often simpler analysis method. However, the ATR spectra reveal significant differences when compared to transmission spectra sometimes leading to confusion in the interpretations. Indeed, optical effects play a prominent role in the ATR spectral profile and their identification is mandatory for obtaining quantitative information regarding molecular/particle orientation or film thickness. The objective of the present study was to perform exact spectral simulations of montmorillonite films by making use of optical theory, including the determination of the anisotropic optical constants from the experimental reflectance spectra by Kramers-Kronig (KK) transformation. This methodology was used: (1) to choose the appropriate optical conditions for advanced and reliable characterization of clay minerals; (2) to extract quantitative information such as the estimation of the film thickness; and (3) to discriminate optical phenomena (optical interferences) from chemical/structural features of the sample.
CFD study of oil-jet gear interaction flow phenomena in spur gears
Authors: Keller M.C. , Kromer C. , Cordes L. , Schwitzke C. , Bauer H.-J.
Published: June 2020

Oil-jet lubrication and cooling of high-speed gears is frequently employed in aeronautical systems, such as novel high-bypass civil aero engines based on the geared turbofan technology. Using such oil-jet system, practitioners aim to achieve high cooling rates on the flanks of the highly thermally loaded gears with minimum oil usage. Thus, for an optimal design, detailed knowledge about the flow processes is desired. These involve the oil exiting the nozzle, the oil impacting on the gear teeth, the oil spreading on the flanks, the subsequent oil fling-off, as well as the effect of the design parameters on the oil flow. Better understanding of these processes will improve the nozzle design phase, e.g. regarding the nozzle positioning and orientation, as well as the nozzle sizing and operation.

Most related studies focus on the impingement depth to characterize the two-phase flow. However, the level of information of this scalar value is rather low for a complete description of the highly dynamic three-dimensional flow. Motivated by the advancements in numerical methods and the computational resources available nowadays, the investigation of the oil-jet gear interaction by means of computational fluid dynamics (CFD) has come into focus lately.

In this work, a numerical setup based on the volume-of-fluid method is presented and employed to investigate the two-phase flow phenomena occurring in the vicinity of the gear teeth. The setup consists of a single oil-jet impinging on a single rotating spur gear. By introducing new metrics for characterizing the flow phenomena, extensive use of the possibilities of modern CFD is made, allowing a detailed transient and spatially resolved flow analysis. Thus, not only the impingement depth, but also the temporal and spatial evolution of wetted areas on the gear flanks, as well as the evolution of the oil volume in contact with the gear flanks are extracted from the simulation data and compared in a CFD study.

The study consists of 21 different simulation cases, whereby the effect of varying the jet velocity, the jet inclination angle, the jet diameter, and the gear speed are examined. Consistent results compared to a simplified analytical approach for the impinging depth are obtained and the results for the newly introduced metrics are presented.
Interferometric discrimination of cross-track bed clutter in ice-penetrating radar sounding data
Authors: Scanlan Kirk M. , Rutishauser Anja , Young Duncan A. , Blankenship Donald D.
Published: June 2020

The interpretations of relevant interfaces (i.e. the surface and bed) in radar sounding datasets over glaciers and ice sheets are primary boundary conditions in a variety of climate studies and particularly subglacial water routing models. It is therefore necessary to ensure these interpretations are consistent and not affected by cross-track clutter. For the surface interface, interferometry and a family of methods relying on digital elevation models have been used to successfully discriminate cross-track surface clutter. Here we present how interferometry can be applied to the problem of basal clutter from cross-track bed topography. Our approach is based on a comparison of the differential phases of ambiguous reflectors that may represent bed clutter and the differential phase of a reflector in an adjacent area that appears unaffected by basal clutter. The reflector yielding the smallest interferometric phase difference relative to the unambiguous bed reflector is considered to represent its consistent continuation. We successfully demonstrate our approach using 60 MHz center frequency MARFA data collected over Devon Ice Cap in the Canadian Arctic. Finally, we investigate the effects of clutter-affected and interferometry-corrected bed interpretations on ice layer thickness estimates, basal hydraulic head gradients and the potential extent of inferred subglacial water bodies.
Just the facts: Risk stratifying nontraumatic back pain for Cauda Equina Syndrome in the emergency department
Authors: Polsky Zoe , Greidanus Margriet , Pandya Anjali , Jacobs W. Bradley
Published: June 2020

A 43-year-old male, with a history of chronic back pain, presents to the emergency department (ED) with acute onset chronic pain. He states he “tweaked something” and has been debilitated by back pain, radiating down both his legs, for 24 hours. He has not had a bowel movement but denies noticing any “saddle anesthesia.” His clinical exam is limited by pain, and it is difficult to determine if he has objective weakness. His perineal sensation is intact, as is his sensation upon digital rectal examination. The patient has a post-void residual of 250 mL, but you are unsure how to interpret this value. As an emergency physician, when should you suspect, and how should you evaluate cauda equina syndrome?
Federal Communications Commission’s experimental radio service as a vehicle for dynamic spectrum access: An analysis of 10 years of experimental licenses data
Authors: Bustamante Pedro , Weiss Martin , Sicker Douglas , Gomez Marcela M.
Published: June 2020

Dynamic spectrum access (DSA) systems, commonly known as spectrum sharing, are considered one of the most promising paths for more efficient spectrum allocation. When talking about DSA, the most discussed topics revolve around particular technologies such as cognitive radios or particular solutions such as the advanced wireless services-3 initiative. However, in this work, we explore a less discussed approach for spectrum sharing: the Federal Communications Commission (FCC)’s experimental radio service (ERS). The ERS grants licenses for experimentation, market trials, and product development in Federal and/or non-Federal bands. Frequencies in these licenses are assigned on a shared basis and not for the exclusive use of any one licensee. Using FCC’s scraped information in the period between 2007 and 2016, we were able to gain a deeper understanding of the ERS. We find that the processing time (i.e., time to get a license) has been reduced from 100 days to an average of 23 days in 2016. Moreover, the assignation process of experimental licenses is characterized great flexibility in terms of the authorized technical and nontechnical characteristics. We also explored what is behind these 10 years of information.
NUMBER THEORY PROBLEMS RELATED TO THE SPECTRUM OF CANTOR-TYPE MEASURES WITH CONSECUTIVE DIGITS
Authors: AI WEN-HUI
Published: June 2020

For integers $p,b\geq 2$, let $D=\{0,1,\ldots ,b-1\}$ be a set of consecutive digits. It is known that the Cantor measure $\unicode[STIX]{x1D707}_{pb,D}$ generated by the iterated function system $\{(pb)^{-1}(x+d)\}_{x\in \mathbb{R},d\in D}$ is a spectral measure with spectrum $$\begin{eqnarray}\unicode[STIX]{x1D6EC}(pb,S)=\bigg\{\mathop{\sum }_{j=0}^{\text{finite}}(pb)^{j}s_{j}:s_{j}\in S\bigg\},\end{eqnarray}$$ where $S=pD$. We give conditions on $\unicode[STIX]{x1D70F}\in \mathbb{Z}$ under which the scaling set $\unicode[STIX]{x1D70F}\unicode[STIX]{x1D6EC}(pb,S)$ is also a spectrum of $\unicode[STIX]{x1D707}_{pb,D}$. These investigations link number theory and spectral measures.
Sex-specific response to delayed and repeated mating in spider mite Tetranychus urticae
Authors: Li Guang-Yun , Zhang Zhi-Qiang
Published: June 2020

Sexual interaction is an important activity that determines the reproductive schedule of organisms and can ultimately influence the fitness traits of both sexes. Although the influence of sexual interaction on the fitness of females has been extensively determined, little is known about the effects on males, which often have different mating strategies and optimal mating regimes from those of females. To understand how mating regimes (timing and frequency) modulate the fitness in both sexes, we used spider mite (Tetranychus urticae) to investigate the influence of delayed mating and repeated mating on the fitness of male and female. For females, the unmated and the delayed mating females outlived those mated immediately after adult emergence. The repeated mating shortened the lifespan of females that mated at 1-day-old, but not that mated 7-day-old. However, no significant variation in lifespan was observed for males across different mating regimes. We found although delayed mating significantly reduced the daily reproductive rate of the females, there was no significant difference in lifetime reproduction of females across treatments because the delayed mating females increased their reproductive lifespan as a compensation. Our study highlighted that the time and frequency of sexual interaction showed a sex-specific consequence on male and female spider mites, indicating that sexual interaction incurs a higher cost to females which have a much lower optimal mating frequency than males.
Soft Balancing, Binding or Bandwagoning? Understanding Institutional Responses to Power Disparities in the Americas
Authors: Levick Laura , Schulz Carsten-Andreas
Published: June 2020

What strategies will states pursue in managing their relations with more powerful neighbours? International Relations scholarship identifies a wide range of policy options open to “secondary states,” including soft balancing, bandwagoning and institutional binding. We provide a conceptual framework to distinguish between these similar and often conflated institutional strategies on the basis of two dimensions: threat perception and inclusiveness. We then apply this framework to the inter-American system. Analyzing original data on treaty action between 1946 and 2015, we find that secondary states’ adherence to multilateral agreements increases when the United States participates and when states do not perceive the hegemon to be a threat. These findings suggest that institutional binding captures the dynamics of inter-American cooperation more adequately than either soft balancing or bandwagoning: states balance against perceived threats but bind their friends.
Filament simulations in regions of highly-varying parallel connection length
Authors: Shanahan B. , Huslage P.
Published: June 2020

The island divertor topology of the Wendelstein 7-X (W7-X) scrape-off-layer exhibits regions of highly varying connection length. Here, we present drift-plane simulations of seeded filaments in regions of sharp transitions in parallel connection length – a parameter which dictates the propagation regime for plasma blobs. It is determined that a transition in parallel connection length alters the trajectory of filaments; filaments which enter regions of lower connection length are decelerated, and vice versa. It is also determined that if the lobes of a potential dipole created by diamagnetic drifts within the filament exist in two regions of distinct parallel connection length, the filament is then steered towards the region of higher connection length. The extreme case of a narrow region of varying connection length can also alter the trajectory of a filament, depending on the extent of this region. Finally, simulations mimicking the view from the W7-X gas puff imaging (GPI) diagnostic view plane are presented. It is determined that filaments in the view of the W7-X GPI diagnostic exhibit a predominantly poloidal propagation due to the radial electric field, since the radial velocity is relatively small.
Central blood pressure in adults screened for a genetic polymorphism in folate metabolism
Authors: Rooney M. , Hughes C. F. , Strain J. J. , Clements M. , Blair R. , McNulty H. , Ward M.
Published: June 2020

As the primary risk factor for cardiovascular disease (CVD), hypertension is the leading cause of preventable, premature mortality globally. Hypertension, or elevated blood pressure (BP), has a number of well-established risk factors, including genetics. A common C677T polymorphism in the gene encoding the folate metabolising enzyme methylenetetrahydrofolate reductase (MTHFR) affects 10–12% of UK and Irish populations and has been linked with 24–87% increased risk of hypertension globally. Evidence from randomised controlled trials (RCTs) conducted at this Centre has shown BP to be highly responsive (by 5–13 mmHg) to supplementation with riboflavin (MTHFR co-factor), an effect confined to homozygous individuals (TT genotype). To date, our trials have focused on peripheral BP; however, additional measures of vascular health such as central pressure are reported to be more closely correlated with CVD risk. Investigation of central BP, augmentation index (AIx) and pulse pressure amplification (PPA) may thus offer further insight into the role of this gene-nutrient interaction in blood pressure. The present study aims to investigate BP, and measures of vascular health in healthy adults stratified by MTHFR 677 genotype. Apparently healthy adults aged 18–60 years were recruited from workplaces across Northern Ireland and screened for MTHFR genotype via buccal swab. Clinic BP, anthropometry and blood sample were measured in TT individuals (n 209) and age and sex-matched CC (n 98) and CT (n 102) controls. AIx and central BP were assessed using SphygmoCor® (AtCor Medical, Australia). Preliminary results demonstrate higher BP in individuals with the MTHFR 677TT genotype compared to non-TT controls (systolic BP 134.7 ± 13.8 mmHg vs 129.7 ± 12.4 mmHg, P < 0.001; diastolic BP 81.6 ± 9.5 mmHg vs 79.7 mmHg ± 8.9 mmHg, P = 0.023, respectively). The MTHFR 677TT genotype group had significantly higher central systolic BP (119.4 ± 11.8 vs 116.7 ± 10.9 mmHg, P = 0.018), central pulse pressure (P = 0.006) and central mean pressure (P = 0.011) compared to the non-TT group. No significant differences for central diastolic BP, pulse pressure amplification, pulse pressure ratio and augmentation index were observed. This study confirms the phenotype of elevated BP in individuals with the C677T polymorphism in the gene encoding MTHFR. For the first time, this study reports that individuals with the MTHFR 677TT genotype have higher central systolic BP, central mean pressure and pulse pressure. Further investigations through RCTs investigating the effect of the MTHFR cofactor, riboflavin, on central blood pressure in these genetically at-risk adults are warranted.
Can a Nordic diet be implemented as a new strategy for successful long-term weight loss maintenance in subjects with obesity?
Authors: Cloetens Lieselotte , Sedin Åsa , Landin-Olsson Mona
Published: June 2020

Introduction

A key problem in all weight-loss programs to fight obesity is the extent to which the body weight is maintained on a long-term basis. The study examines whether the 1-year consumption of healthy Nordic foods can result in better sustainable weight control compared to a control diet.

Material and methods

After a successful 6-week VLCD period in obese subjects (n = 80, 52 ± 10y, BMI 34.4 ± 3.1 kg/m2, 69% female; 93% completers, -10.9 ± 3.0 kg, p < 0.001), the subjects were randomized to a new Nordic diet (NND) and a traditional Nordic diet (TND) group. The following 1-year period was a body weight maintenance period where the diets were implemented ad libitum. Weight, BMI, waist circumference and sagittal abdominal diameter were measured at 0 (immediately after VLCD), 6 and 12 months. Results are reported as mean ± SEM. Differences in the anthropometric parameters between the diets at different time points compared to the start of the dietary intervention were statistically evaluated using a general linear model (GLM-ANOVA, Minitab Inc.).

Results

Forty-three subjects were randomized to NND and 37 to TND. In the NND group, 31 subjects completed the 6-month visit and 30 subjects 12-month visit. In the TND group, 24 and 21 completed 6-month and 12-month visit, respectively. We observed a non-significant difference in weight change at 6 months between NND (0.04 ± 0.87kg) and TND (2.65 ± 1.08kg). At 12 months, the weight change was significantly different between the diets (NND 1.94 ± 0.99 kg and TND 5.69 ± 1.41 kg, p = 0.029, R2 = 9.39). Change in the BMI at 12 months was significantly lower for NND (0.65 ± 0.33 kg/m2) compared to TND (1.87 ± 0.46 kg/m2, p = 0.034, R2 = 8.87) but not at 6 months (0.01 ± 0.30 kg/m2 for NND and 0.84 ± 0.36 kg/m2 for TND). Differences in waist circumference (at 6 months 0.26 ± 0.93 cm for NND and 3.30 ± 1.45 cm for TND; at 12 months 1.04 ± 1.01 cm for NND and 3.85 ± 1.79 cm for TND) were not statistically different. The sagittal abdominal diameter was borderline statistically different at 6 months (NND -0.28 ± 0.29 cm and TND 0.49 ± 0.22 cm, p = 0.049, R2 = 7.09) but not at 12 months (NND 0.41 ± 0.38 cm and TND 1.23 ± + 0.42cm).

Conclusion

Results show a tendency that the type of diet has an impact on successful weight maintenance, with a benefit for the NND. Further statistical analyses including dietary compliance and biomarkers are needed and will be performed. Moreover, the study is ongoing with a total of 2-year follow-up.
Comparing effects of polyunsaturated fatty acids derived from marine and plant sources on endothelial cell inflammation
Authors: Baker Ella , Miles Elizabeth , Calder Philip
Published: June 2020

High consumption of ω-3 long chain polyunsaturated fatty acids (PUFAs) has long-term health benefits. The principal dietary source of these ω-3 PUFAs (eicosapentaenoic acid, EPA and docosapentaenoic acid, DHA) is seafood, particularly oily fish. However current fish stocks are decreasing, indicating a need for alternative sources of bioactive PUFAs. Plant-derived ω-3 PUFAs (alpha-linolenic acid, ALA and stearidonic acid, SDA) may be able to provide land-based sustainable sources, but their functionality has been underexplored.

Anti-inflammatory effects of ALA and SDA were compared to EPA and DHA in cultured EA.hy926 endothelial cells. Cells were treated with PUFAs (10, 25 and 50 μM) for 48 hours prior to stimulation with tumour necrosis factor for 24 hours. PUFAs incorporation was measured by gas chromatography and inflammatory responses were measured by ELISA, RT-PCR, western blot and flow cytometry. Adhesion of THP-1 monocytes to EA.hy926 cells was determined using a static adhesion assay.

All PUFAs were incorporated into EA.hy926 cells in a dose-dependant manner (10 and 50 μM). Pre-treatment with ALA, SDA, EPA and DHA (50 μM) had differential effects on inflammatory responses in EA.hy926 cells depending on PUFA and response examined.

EA.hy926 cells pre-treated with SDA had lower concentrations of soluble ICAM-1 (p < 0.05); however EPA and DHA resulted in greater reduction (p < 0.0001). EPA and DHA pre-treated EA.hy926 cells had significantly lower concentrations of IL-6 (p < 0.0001), IL-8 (p < 0.0001) and MCP-1 (p < 0.05, p < 0.01). ALA pre-treatment did not significantly affect any of the cytokines examined. Lower cell surface expression of ICAM-1 (p < 0.05), was seen for EA.hy926 cells pre-treated with SDA again to a lesser extent than EPA and DHA (p < 0.001, p < 0.0001), with no effect seen after ALA treatment.

EA.hy926 cells pre-treated with ALA had significantly higher relative gene expression of NFKB (p < 0.05), as well as a tendency for more phosphorylated NFKBp65 protein (p < 0.06). In contrast, EA.hy926 cells pre-treated with DHA had significantly less phosphorylated NFKB (p < 0.0001). EA.hy926 cells with DHA treatment had significantly higher relative gene expression of PPARa (p < 0.05). SDA and EPA had no effect on expression of either of the genes or proteins examined.

Finally pre-treatment with ALA, SDA and DHA all resulted in reduced adhesion of THP-1 monocytes to EA.hy926, however this effect not observed with EPA.

Marine derived PUFA, particularly DHA, resulted in potent anti-inflammatory effects within this endothelial cell model. Of the two plant derived PUFAs, SDA treatment lead to some anti-inflammatory effects, which were not seen after treatment with ALA.
Effect of vitamin D supplementation on vitamin D status in pregnant women: findings from the MO-VITD study
Authors: Alhomaid Raghad , Mulhern Maria , Cassidy Laura , Laird Eamon , Healy Martin , Strain Sean , Livingstone Barbara , Parker Michael , McCann Mary
Published: June 2020

Pregnant women who are overweight/obese are particularly vulnerable to vitamin D insufficiency owing to higher physiological requirements and lower status (25(OH)D concentrations) associated with obesity. Achieving adequate maternal vitamin D status with current recommendations (10μg/d) remains controversial.

This study examined supplementation effects (10μg-vs-20μg vitamin D3/d) throughout pregnancy (12 weeks gestation until delivery) on vitamin D status of normal weight, overweight and obese pregnant women and on cord blood, using a double-blind randomised vitamin D intervention study (MO-VITD). 240 pregnant women were recruited throughout the year at antenatal clinics in Northern Ireland (equal numbers of normal weight (18.5–24.9 kg/m2), overweight (25–29.9 kg/m2), and obese (> 30kg/m2)). Non-fasting maternal blood samples were collected at 12, 28 and 34–36 weeks gestation and from the umbilical cord after delivery and analysed for total serum 25(OH)D using LCMS.

A high prevalence of vitamin D insufficiency (25–50nmol/L) was found in the 1st trimester in both treatment groups (41.5% and 48.8%; 10μg vs. 20μg respectively). Maternal 25(OH)D concentrations increased from the 1st to 3rd trimester in both the 10μg/d and 20μg/d groups, with a higher increase in the 20μg group (17.1 ± 24.7 and 28.8 ± 33.3nmol/L, P = 0.002). There was no difference in cord blood 25(OH)D concentrations between treatment groups.

Women who started pregnancy with insufficient 25(OH)D concentrations remained insufficient throughout pregnancy in the 10μg/d group (49.9 ± 28.2nmol/L at trimester 3). In the 20μg/d group, women starting pregnancy as insufficient achieved levels of sufficiency in the 2nd (58.9 ± 30.6nmol/L) and 3rd (64.0 ± 35.9nmol/L) trimesters. Women who started pregnancy with sufficient vitamin D status (25(OH)D > 50nmol/L), maintained levels of sufficiency throughout pregnancy irrespective of treatment group (83.1 ± 24.4 and 96.7 ± 30.7 at trimester 3 in 10μg/d and 20 μg/d groups respectively); findings were similar across all BMI categories.

Obese women who started pregnancy with an insufficient status were found to have deficient cord blood (25(OH)D < 25 nmol/L) in both the 10μg/d and 20μg/d groups (19.4 ± 20.2 vs. 19.5 ± 9.4nmol/L respectively), whilst obese women who started pregnancy with sufficient status (> 50nmol/L) had cord blood concentrations considered insufficient (40.2 ± 18.4 vs. 44.2 ± 15.6nmol/L; 10μg vs. 20μg groups respectively).

Based on our findings of the high prevalence of vitamin D insufficiency in early pregnancy, maternal vitamin D supplementation of 20μg/d is advisable to maintain maternal vitamin D status in pregnant women in Northern Ireland.
Association between severe sarcopenic obesity and respiratory incidence and mortality: an obesity paradox.
Authors: Petermann-Rocha Fanny , Gray Stuart R. , Pell Jill P. , Celis-Morales Carlos
Published: June 2020

Introduction

Obesity remains one of the biggest health challenges worldwide. Sarcopenia, a progressive loss of muscle strength, is associated with a higher risk of disability and lower quality of life. Both conditions can occur independently of each other; however, share a common inflammatory pathway, leading to serious health problems. Previous studies have shown a positive association between severe sarcopenia and respiratory disease incidence/mortality, however, it is unclear if this association is modified by obesity. The aim of this work, therefore, was to investigate the association of severe sarcopenia and severe sarcopenic-obesity with respiratory incidence and mortality in the UK Biobank cohort.

Material and methods

242,572 white participants from the UK biobank study were included. Severe sarcopenia was defined as the combination of low muscle mass, low grip strength and slow gait speed. Severe sarcopenic-obesity was defined, using 3 different criteria. The combination of severe sarcopenia plus at least one of the following criteria: BMI ≥ 30 kg/m2, waist circumference (WC) > 88 cm in women and > 102 cm in men, or the two highest quintiles of body fat (60%). Associations between severe sarcopenic and severe sarcopenic-obesity and respiratory incidence and mortality were investigated using Cox-proportional hazard models.

Results

In people without sarcopenia, high BMI, WC and body fat were associated with a reduced risk of respiratory disease mortality (HR: 0.70 [0.52; 0.85], HR: 0.74 [95%CI: 062: 088] and HR: 0.74 [95%CI: 0.63; 0.88], respectively). In comparison to people without sarcopenia or obesity, those with severe sarcopenia had three times higher risk of respiratory disease incidence (HR: 3.13 [95%CI: 2.25; 4.35]) and five times higher risk of mortality (HR: 5.37 [95%CI: 2.96: 9.74]). However, sarcopenic-obesity, based on WC and body fat, was only associated with a moderately increased respiratory disease incidence (HR 1.60 [95%CI: 1.04; 2.46] and HR: 1.52 [1.04: 2.22], respectively). There were no associations between respiratory mortality and sarcopenic-obesity.

Discussion

Higher levels of adiposity may be a protective factor against respiratory mortality and could reduce the effect of severe sarcopenia over this disease. However, the mechanism behind this association needs to elucidate.
The associations of major foods and fibre with risk of ischaemic and haemorrhagic stroke: results from the prospective EPIC study.
Authors: Tong Tammy Y.N. , Appleby Paul N. , Key Timothy J. , Perez-Cornago Aurora
Published: June 2020

Introduction

The evidence of associations between individual foods and dietary fibre with subtypes of stroke (ischaemic and haemorrhagic) is not conclusive. We aimed to investigate this in a large prospective cohort.

Materials and methods

We analysed data on 418,329 men and women from the European Prospective Investigation into Cancer and Nutrition (EPIC) study. Consumption of various animal-sourced foods (red and processed meat, poultry, fish, dairy, egg), plant-sourced foods (fruit and vegetables, legumes, nuts and seeds) and dietary fibre was assessed using validated country-specific questionnaires, calibrated with 24-hour recalls. Using multivariable Cox regressions adjusted for energy intake and socio-demographic, lifestyle and physiological confounders, we estimated hazard ratios of fatal and non-fatal ischaemic, haemorrhagic and total (i.e. ischaemic, haemorrhagic and unspecified) stroke associated with calibrated increment differences in consumption of each food or dietary fibre.

Results

Over an average of 12.7 years of follow-up, we observed 4281 cases of ischaemic stroke, 1430 cases of haemorrhagic stroke, and 7378 cases of total stroke. For ischaemic stroke, lower risks were observed with higher consumption of fruit and vegetables (hazard ratio (HR); 95% confidence interval (CI) for per 200g/d of calibrated intake, 0.87; 0.82–0.93) and dietary fibre (per 10g/d, HR 0.77; 95% CI 0.69–0.86) (p-trend < 0.001 for both); more modest inverse associations were also observed for milk (per 200g/d, HR 0.95; 95% CI 0.91–0.99, p-trend = 0.02), yogurt (per 100g/d, HR 0.91; 95% CI 0.85–0.97, p-trend = 0.004) and cheese (per 30g/d, HR 0.88; 95% CI 0.81–0.97, p-trend = 0.008), while a modest positive association was observed with higher red meat consumption (per 50g/d, HR 1.14; 95% CI 1.02–1.27, p-trend = 0.02). For haemorrhagic stroke, higher risk was associated with higher egg consumption (per 20g/d, HR 1.25; 95% CI 1.09–1.43, p-trend = 0.002). For total stroke, associations were consistent with those of both subtypes; we observed inverse associations for fruit and vegetables (HR 0.89, 95% CI 0.85–0.93), dietary fibre (HR 0.80, 95% CI 0.74–0.86), yogurt (HR 0.91, 95% CI 0.87–0.96), cheese (HR 0.88, 95% CI 0.82–0.94), and positive associations for red and processed meat (HR 1.18, 95% CI 1.05–1.33) and egg (HR 1.07, 95% CI 1.01–1.14).

Discussion

To conclude, risk of ischaemic stroke was inversely associated with consumption of fruit and vegetables, dietary fibre and dairy foods, and positively associated with red meat, while risk of haemorrhagic stroke was positively associated with egg consumption. Causality of the associations cannot be determined in this observational study.
Vitamin K-biofortification of eggs: effect on egg quality and hen performance parameters
Authors: O'Sullivan Siobhan , Hull George , Danaher Martin , Ball Elizabeth , Cashman Kevin
Published: June 2020

Vitamin K has important physiological functions which relate to blood coagulation (its classical role), bone health, inhibition of arterial calcification, as well as anti-inflammatory effects. National nutrition survey data have shown that over half of all adults in Ireland and the UK have low vitamin K1 intakes (£1 μg/kg body weight/d). Vitamin K biofortification of food may be an important complementary food-based approach for improving vitamin K intakes. Our study aimed to explore the feasibility of producing vitamin K-biofortified eggs via increasing the vitamin K3 content of the hen diet, and to examine any effects on hen performance and egg/eggshell quality parameters. A 12-week hen feeding trial was conducted in the Agri-Food and Biosciences Institute, Belfast, UK. Hyline chickens (n = 128) were randomized into 4 treatment (T) groups (n = 32 hens/group) and fed diets containing 3 (T1-industry standard), 12.9 (T2), 23.7 (T3) and 45.7 (T4) mg vitamin K3/kg of feed. Hens were provided feed ad libitum and feed intake was recorded weekly. Eggs were collected daily and weighed. While egg quality and vitamin K content was assessed at week 0, 4, 6, 8 and 12, the trial endpoint (week 12) data was prioritized for the current analysis. Total vitamin K content (i.e., vitamin K1 plus menaquinone (MK)-4 and MK-7) of composite samples (n = 12 eggs/treatment), measured using a novel, sensitive liquid chromatography-mass spectrometry method at Teagasc, increased from 22.4 μg/100 g (whole egg) in T1 (control and commercial level of vitamin K3) to 57.8 μg/100 g in T4. MK-4 was the most abundant form of vitamin K found in the eggs. Eggshell weight and eggshell thickness in T2 and T3 (but not T4) were significantly higher than in T1 (by 20–28%, P < 0.05). Likewise, based on colourimetric assessment, yellowness (parameter b*) of the egg yolk in all three biofortified groups was significantly higher compared to T1 (by 27–45%, P < 0.05). Haugh unit of the eggs and hen performance parameters, such as feed intake, feed conversion ratio and egg production, were unaffected by vitamin K-biofortification. In conclusion, increasing the level of addition of vitamin K3 to hen feed significantly increased the total vitamin K content of eggs, and without any evidence of negative effects on egg quality or hen performance. Consumption of an average sized (60 g) vitamin K-biofortified egg could contribute an additional 35 μg total vitamin K. The effects on eggshell parameters could be of importance in terms of revenue loss due to breakages.
Wild strawberry polyphenols exhibit gut-protective bioactivity following in vivo digestion
Authors: Gill Chris , Latimer Cheryl , Ternan Nigel , Pourshahidi Kirsty , Fontana Massimilano , Lawther Roger , O'Connor Gloria , Conterno Lorenzo , Fava Francesca , Tuohy Kieran
Published: June 2020

Berries are one of the most commonly consumed sources of bioactive polyphenols and these compounds may exert protective effects against initiation of colorectal cancer (CRC) by reducing DNA damage. The inverse correlation between fruit and vegetable consumption and the incidence of CRC is well established, hence the role of berry derived bioactive phytochemicals in promotion of gut health is of interest. Ileostomy studies provide a unique insight into food digestion, allowing identification of physiologically relevant dietary phytochemicals and their metabolites. Here, we hypothesised that physiologically relevant levels of Italian wild strawberry metabolites exiting the ileum would be both bioavailable and would in turn exert positive effects on gut health markers.

Five ileostomists completed a wild strawberry feeding study (11/NI/0112), ileal fluid was collected pre (0 h) and post (8 h) consumption of strawberries (225 g) and assessed for phytochemical composition by LCMSn. We simulated the interaction of the ileal fluids with colonic microbiota over a 24 h period (0, 5,10, 24 hr) using in vitro gut fermenter models. Nutri-kinetic analysis using LCMSn demonstrated significant increases in the concentration of gut microbiota-mediated polyphenolic metabolites over time, including 3-(4hydroxyphenyl) propionic acid, 3-(3-hydroxyphenyl) propanoic acid, hydroxybenzoic acid and urolithin A. While changes in the bacterial composition of the gut fermenter model(s) were monitored using fluorescent in situ hybridisation analysis (FISH) with validated probes for Total bacteria, Bifidobacterium genus, Clostridium histolyticum/perfringens group, Faecalibacterium prausnitzii, Eubacterium rectale group, Bacteroides, Lactobacilli and Enterobacteria; limited changes were observed.

Bioactivity of the post-berry consumption ileal fermentates was assessed on two colonocyte cell lines (HT29 and CCD841 CON (normal)) using the oxidative challenge COMET assay. Post-berry ileal fermentate (24 h) from all five ileostomists significantly (p < 0.01) decreased DNA damage (expressed as %Tail DNA) in both HT29 cells (~45%) and CCD841 cells (~25%) compared to untreated controls.

To conclude, strawberry phytochemicals were available for colonic fermentation following ileal digestion and human microbiota-mediated fermentation which subsequently increased overall levels of polyphenolic metabolites, the post berry fermentates were demonstrated to reduce DNA damage in colonocytes.
Cytokines and adipokines in db / db mice after sweetener consumption
Authors: Valdes-Ramos Roxana , Martinez-Carrillo Beatriz Elina , Gutierrez-Pliego Laura Elisa , Escoto-Herrera Jorge Alberto , Mondragon-Velazquez Talia
Published: June 2020

Type 2 Diabetes Mellitus is a chronic diseases with very high morbidity and mortality worldwide; associated with obesity and hypertension and representing at least 90% of all cases of diabetes. It is characterized by insulin resistance in peripheral tissues and a deterioration in its secretion by the pancreatic β-cell. The control and treatment of these patients is a low-carbohydrate diet, for which non-nutritive sweeteners such as sucralose and stevia are being used, maintaining the sweet taste. It is known that these sweeteners are harmless, but the results so far are still controversial. To identify alterations in the secretion of cytokines and adipokines in db/db mice with consumption of sweeteners. We conducted a randomized, controlled study, with 24 eight week-old male db/db mice. They were divided into 4 groups: a) Control (CL), b) Sucrose (SUC), c) Sucralose (SUCL) and c) Stevia (ST). The animals were fed a normal diet and water ad libitum. The sweeteners were administered for 8 weeks diluted in purified water at 41.66 mg/mL of Sucrose and 4.16 mg/mL of Sucralose or Stevia. Blood glucose was quantified daily; water consumption with and without sweetener, food, and BMI, were quantified weekly. The concentration of IL-4, IL-5, IL-6, IL-10, IL-12, IL-17, INF-γ, TGF-β and TNF-α, insulin, adiponectin, resistin and peptide-C in plasma were determined by luminometry. Glucose was found increased at the end of 8 weeks in the SUC group, compared to CL. They consumed more food, water with and without sweetener in the SUC group (p < 0.001), compared with the controls. BMI was higher in the SUC group, compared with the ST group (p < 0.019). ST decreased the secretion of IL-4, IL-5, IL-6, IL-10, IL-12, IL-17, INF-γ and TNF-α, adiponectin and insulin (p < 0.001), but it increased TGF-β, without modifications in resistin (p < 0.051). On the other hand, SUC decreased the secretion of IL-4, IL-5, IL-10, IL-12, INF-γ, TNF-α, adiponectin, insulin and C-peptide (p < 0.028), but increased IL-6, IL-17 and resistin (p < 0.001), without modifications in TGF-β. Sucralose is a non-nutritive sweetener that caused an increase in the BMI of db/db mice, this because it increased the consumption of food. It also modified the secretion of adipokines; while Stevia decreased the secretion of pro-inflammatory cytokines such as IL-4, IL-5, IL-6, IL-10, IL-12, IL-17, INF-γ and TNF-α. Our results suggest that sweetener consumption may alter the inflammatory profile and the production of adipokines in subjects with type 2 diabetes mellitus.
Weight loss at your fingertips – personalized nutrition using fasting glucose and insulin
Authors: Ritz Christian , Astrup Arne , Larsen Thomas M. , Hjorth Mads F.
Published: June 2020

Introduction

Precision medicine is changing the way people are diagnosed and treated into a more personalized approach. In medical research, several statistical methods have been proposed for estimating personalized treatment effects. However, in nutritional science these methods have hardly been used. By re-evaluation of pre-treatment biomarker data, we demonstrate how two diets cause differential weight loss depending on pre-treatment fasting plasma glucose (FPG) and fasting insulin (FI) levels.

Materials and Methods

Overweight people with increased waist circumference were randomly assigned to receive an ad libitum New Nordic Diet (NND) high in dietary fiber and whole grain or an Average Danish (Western) Diet (ADD) for 26 weeks. All foods were provided free of charge. Body weight was measured throughout the study and blood was drawn before randomization from where FPG and FI were analyzed. Weight was described by linear mixed models including biomarker-diet group interactions, covariate adjustment, and participant-specific random effects. Personalized predictions of additional weight loss from NND compared to ADD given specific values of FPG or FI were estimated as contrasts of intercepts and slopes obtained from the biomarker-diet group interaction term.

Results

Baseline FPG predicted a 3.00 (1.18;4.83, n = 181, P = 0.001) kg larger weight loss per mmol/L from choosing NND over ADD. For instance, a baseline FPG level of 4.7 mmol/L would lead to an average of 1.42 kg larger weight loss on NND vs. ADD (above 0.41 kg with 95% certainty), whereas the average effect size would be 8.33 kg (above 5.50 kg with 95% certainty) among subjects with FPG level of 7.0 mmol/L. Among individuals with FPG < 5.6 mmol/L, each pmol/L lower baseline FI predicted a 0.039 (95% CI 0.017;0.061, n = 143, P < 0.001) kg larger weight loss from choosing NND over ADD. For instance, a baseline FI level of 25 pmol/L would lead to an average larger weight loss of 4.10 kg on NND vs. ADD (> 2.51 kg with 99% certainty). Likewise, a baseline FI level of 75 pmol/L would result in an average effect size of 2.15 kg (> 1.11 kg with 99% certainty).

Discussion

Use of pre-treatment FPG and FI led to truly individualized predictions of treatment effect of introducing more fiber and whole grain in the diet on weight loss, ranging from almost no effect to losing more than 8 kg. These findings tentatively suggest that re-evaluation of data from existing randomized controlled trials through suitable statistical methods may have a great potential.