Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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Poor vitamin d status in active pulmonary tuberculosis patients and its correlation with leptin and tnf-α
Wang, Qiuzhen ; Ma, Aiguo ; Gao, Tianlin ; Liu, Yufeng ; Ren, Lisheng ; Han, Lei ; Wei, Boyang ; Liu, Qian ; Dong, Chunjiang ; Mu, Yuze ; Li, Duo ; Kok, Frans J. ; Schouten, Evert G. - \ 2019
Journal of Nutritional Science and Vitaminology 65 (2019)5. - ISSN 0301-4800 - p. 390 - 398.
Co-morbidity - Diabetes - Immune activity - Inflammatory markers - Leptin - Serum 25(OH)D - TNF-α - Tuberculosis

Summary Vitamin D deficiency (VDD) is common in tuberculosis (TB) and may be implicated in the etiology of the disease and in its clinical course. The aim of this study was to investigate the association between leptin, inflammatory markers and VD status in TB patients, stratified for presence or absence of diabetes mellitus (DM). Two hundred ninety-nine TB patients were recruited from October 2015 to August 2016. Also, 91 normal controls were included. The information including socio-demographics, dietary intake and living habits was obtained by face-to-face interview. Serum concentrations of leptin and TNF-α, CRP and IL-6 were compared between TB patients with and without severe VDD (SVDD). Pearson’s correlation was used to analyze the association between TNF-α, leptin and 25-hydroxyvitamin D (25(OH)D). A significantly higher prevalence of VDD and SVDD was observed in TB patients compared with normal controls (93.0% vs 70.3%, 65.9% vs 3.3% respectively). Concentration of leptin was significantly lower, while TNF-α higher in TB patients with SVDD compared to those without (p<0.05). After adjustment for con-founders, leptin was positively associated with 25(OH)D (r=0.210, p=0.002) with similar correlation in TB patients with DM (r=0.240, p=0.020). A negative association between TNF-α and 25(OH)D was observed (r=-0.197, p=0.003), which was significant only in the subgroup without DM (r=-0.304, p=0.001). Our findings indicate that a higher VD status in TB patients may be related to higher immune activity and less serious tissue damage, and that this relation is different according to presence or absence of DM co-morbidity.

A lack of complementarity for water acquisition limits yield advantage of oats/vetch intercropping in a semi-arid condition
Zhang, Yue ; Duan, Yu ; Nie, Jiayi ; Yang, Jie ; Ren, Jianhong ; Werf, Wopke van der; Evers, Jochem B. ; Zhang, Jun ; Su, Zhicheng ; Zhang, Lizhen - \ 2019
Agricultural Water Management 225 (2019). - ISSN 0378-3774
Daily water use - Land equivalent ratio - Productivity - Water equivalent ratio - Water use efficiency

Oats (Avena sativa L.) and hairy vetch (Vicia villosa) are well adapted crop species for production in semi-arid environments, such as in Inner Mongolia, China, where due to variable rainfall, farmers do not apply fertilizer. We hypothesized that the use of a mixture of a cereal and a legume could enhance yields under these low input conditions, because integrating an N-fixing legume in the system could mitigate N limitation for the cereal and enhance its growth. A nine-year (2008–2016) field experiment was set up with three treatments: sole oats, sole vetch and oats/vetch strip intercropping. These cropping systems were grown continuously in the same plots, to allow accrual of long-term effects. Yields and water use were quantified in years 7–9 of the experiment (2014 to 2016). With a 50/50 ratio of the area sown to the two species, the intercropped oats had a relative yield of 0.59 and intercropped vetch had a relative yield of 0.45. Oats was the dominant crop characterized by a relative yield per plant of 1.18, compared to a relative yield per plant of vetch of 0.89. However, the land equivalent ratio (LER), expressing the comparative efficiency of land use in intercropping, and the water equivalent ratio (WER), the comparative system level water use efficiency of the intercrop relative to sole crops, were both not significantly different from one. Thus we reject the hypothesis that oat/vetch intercropping increases land productivity and water use efficiency. From differences in results in years with more rainfall and years with less rainfall, we infer that yields of both species are mostly limited by water availability. On average over the three years, the yield disadvantage of vetch was fully compensated by the yield advantage of oats, due to a lack of complementarity for water acquisition. This conclusion can be generalized to the testable prediction that species selection for productive intercropping should focus on achieving complementarity for traits that interact with the factor most constraining productivity, which was rainfall in this particular crop system under the conditions of the study.

Narrow-wide-row planting pattern increases the radiation use efficiency and seed yield of intercrop species in relay-intercropping system
Raza, Muhammad Ali ; Feng, Ling Yang ; Werf, Wopke van der; Cai, Gao Ren ; Khalid, Muhammad Hayder Bin ; Iqbal, Nasir ; Hassan, Muhammad Jawad ; Meraj, Tehseen Ahmad ; Naeem, Muhammd ; Khan, Imran ; Ur Rehman, Sana ; Ansar, Muhammad ; Ahmed, Mukhtar ; Yang, Feng ; Yang, Wenyu - \ 2019
Food and Energy Security 8 (2019)3. - ISSN 2048-3694
competition - intercropping - land equivalent ratio - radiation use efficiency

Planting arrangements affect radiation use efficiency (RUE) and competitiveness of intercrop species in intercropping systems. Here, we reveal that narrow-wide-row planting arrangement in maize-soybean relay-intercropping system increases the dry matter and competitiveness of soybean, increased the RUE of maize and soybean, and compensates the yield loss of maize by substantially increasing the yield of soybean. In this field study, maize was planted with soybean in different planting arrangements (P1, 20:180, P2, 40:160; P3, 60:140, and P4, 80:120) of relay intercropping, all the relay-intercropping treatments were compared with sole crops of maize (SM) and soybean (SS). Results showed that P1 improved the total RUE 3.26 g/MJ (maize RUE + soybean RUE) of maize and soybean in relay-intercropping system. Compared to P4, treatment P1 increased the soybean competition ratio (CR) values (by 55%) but reduced the maize CR values (by 29%), which in turn significantly improved the yield of soybean by maintaining the maize yield. Generally, in P1, soybean produced 82% of SS yield, and maize produced 88% of SM yield, and it achieved the land equivalent ratio of 1.7. These results suggest that by maintaining the appropriate planting distances between maize and soybean we can improve the competitiveness and yield of intercrop species in relay-intercropping system.

Persistence of land reallocations in Chinese villages: The role of village democracy and households’ knowledge of policy
Ren, Guangcheng ; Zhu, Xueqin ; Heerink, Nico ; Feng, S. ; Ierland, Ekko C. van - \ 2019
Journal of Rural Studies (2019). - ISSN 0743-0167
China - Households' knowledge of policy - Land reallocations - Land tenure security - Village democracy

Land reallocations have been severely restricted in rural China since 1998. Nevertheless, land continues to be reallocated in some regions. Little is known about the forces behind the persistence of land reallocations. In this paper we argue that village self-governance rules affect the implementation of national laws and regulations, and that the election of village leaders and villagers' knowledge of relevant policies are major forces in the use of village self-governance rules for land reallocations. Estimation results based on primary data collected from 124 villages in four provinces in 2015 and 2016 provide evidence that both village democracy and households’ knowledge of the Rural Land Contract Law (RLCL) positively affect the incidence of land reallocations.

Development of a low-alcoholic fermented beverage employing cashew apple juice and non-conventional yeasts
Gamero, Amparo ; Ren, Xiao ; Lamboni, Yendouban ; Jong, Catrienus de; Smid, Eddy J. ; Linnemann, Anita R. - \ 2019
Fermentation 5 (2019)3. - ISSN 2311-5637
Alcoholic beverages - Aroma profile - Cashew apple juice - Hanseniaspora guilliermondii - Non‐conventional yeasts - Saccharomyces cerevisiae - Torulaspora microellipsoides

Cashew apples are by‐products in the production of cashew nuts, which are mostly left to rot in the fields. Cashew apple juice (CAJ), a highly nutritious beverage, can be produced from them. It is rich in sugars and ascorbic acid, but its high polyphenol content makes it bitter and astringent, and therefore difficult to commercialize. The kingdom of fungi contains more than 2000 yeast species, of which only a few species have been studied in relation to their potential to produce aroma compounds. The aim of this research was to develop a new low‐alcoholic fermented beverage to valorize cashew apples. For this purpose, a screening was carried out employing non‐conventional yeast species and some species of the genus Saccharomyces for comparison, followed by a more detailed study with four selected strains cultured at different conditions. The production of volatile aroma compounds as a function of the presence of oxygen, temperature, and yeast species was investigated. The results showed that the more diverse aroma profiles appeared at 25 °C under anaerobic cultivation conditions, where Saccharomyces cerevisiae WUR 102 and Hanseniaspora guilliermondii CBS 2567 excelled in the synthesis of certain aroma compounds, such as β-phenylethanol and its acetate ester (rose aroma). Further studies are needed to test consumer acceptance of these new products.

Joint Assimilation of Leaf Area Index and Soil Moisture from Sentinel-1 and Sentinel-2 Data into the WOFOST Model for Winter Wheat Yield Estimation
Pan, Haizhu ; Chen, Zhongxin ; Wit, Allard de; Ren, Jianqiang - \ 2019
Sensors 19 (2019)14. - ISSN 1424-8220
data assimilation - EnKF - LAI - Sentinel-1 and Sentinel-2 - SM - winter wheat yield - WOFOST

It is well known that timely crop growth monitoring and accurate crop yield estimation at a fine scale is of vital importance for agricultural monitoring and crop management. Crop growth models have been widely used for crop growth process description and yield prediction. In particular, the accurate simulation of important state variables, such as leaf area index (LAI) and root zone soil moisture (SM), is of great importance for yield estimation. Data assimilation is a useful tool that combines a crop model and external observations (often derived from remote sensing data) to improve the simulated crop state variables and consequently model outputs like crop total biomass, water use and grain yield. In spite of its effectiveness, applying data assimilation for monitoring crop growth at the regional scale in China remains challenging, due to the lack of high spatiotemporal resolution satellite data that can match the small field sizes which are typical for agriculture in China. With the accessibility of freely available images acquired by Sentinel satellites, it becomes possible to acquire data at high spatiotemporal resolution (10-30 m, 5-6 days), which offers attractive opportunities to characterize crop growth. In this study, we assimilated remotely sensed LAI and SM into the Word Food Studies (WOFOST) model to estimate winter wheat yield using an ensemble Kalman filter (EnKF) algorithm. The LAI was calculated from Sentinel-2 using a lookup table method, and the SM was calculated from Sentinel-1 and Sentinel-2 based on a change detection approach. Through validation with field data, the inverse error was 10% and 35% for LAI and SM, respectively. The open-loop wheat yield estimation, independent assimilations of LAI and SM, and a joint assimilation of LAI + SM were tested and validated using field measurement observation in the city of Hengshui, China, during the 2016-2017 winter wheat growing season. The results indicated that the accuracy of wheat yield simulated by WOFOST was significantly improved after joint assimilation at the field scale. Compared to the open-loop estimation, the yield root mean square error (RMSE) with field observations was decreased by 69 kg/ha for the LAI assimilation, 39 kg/ha for the SM assimilation and 167 kg/ha for the joint LAI + SM assimilation. Yield coefficients of determination (R2) of 0.41, 0.65, 0.50, and 0.76 and mean relative errors (MRE) of 4.87%, 4.32%, 4.45% and 3.17% were obtained for open-loop, LAI assimilation alone, SM assimilation alone and joint LAI + SM assimilation, respectively. The results suggest that LAI was the first-choice variable for crop data assimilation over SM, and when both LAI and SM satellite data are available, the joint data assimilation has a better performance because LAI and SM have interacting effects. Hence, joint assimilation of LAI and SM from Sentinel-1 and Sentinel-2 at a 20 m resolution into the WOFOST provides a robust method to improve crop yield estimations. However, there is still bias between the key soil moisture in the root zone and the Sentinel-1 C band retrieved SM, especially when the vegetation cover is high. By active and passive microwave data fusion, it may be possible to offer a higher accuracy SM for crop yield prediction.

Impact hotspots of reduced nutrient discharge shift across the globe with population and dietary changes
Wang, Xu ; Daigger, Glen ; Vries, Wim de; Kroeze, Carolien ; Yang, Min ; Ren, Nan Qi ; Liu, Junxin ; Butler, David - \ 2019
Nature Communications 10 (2019)1. - ISSN 2041-1723

Reducing nutrient discharge from wastewater is essential to mitigating aquatic eutrophication; however, energy- and chemicals-intensive nutrient removal processes, accompanied with the emissions of airborne contaminants, can create other, unexpected, environmental consequences. Implementing mitigation strategies requires a complete understanding of the effects of nutrient control practices, given spatial and temporal variations. Here we simulate the environmental impacts of reducing nutrient discharge from domestic wastewater in 173 countries during 1990–2050. We find that improvements in wastewater infrastructure achieve a large-scale decline in nutrient input to surface waters, but this is causing detrimental effects on the atmosphere and the broader environment. Population size and dietary protein intake have the most significant effects over all the impacts arising from reduction of wastewater nutrients. Wastewater-related impact hotspots are also shifting from Asia to Africa, suggesting a need for interventions in such countries, mostly with growing populations, rising dietary intake, rapid urbanisation, and inadequate sanitation.

Cooling Urban Water Environments : Design Prototypes for Design Professionals
Cortesão, J. ; Lenzholzer, S. ; Klok, Lisette ; Jacobs, C.M.J. ; Kluck, Jeroen - \ 2019
In: PLEA 2018: Smart and Healthy Within the Two-Degree Limit. - PLEA - p. 520 - 525.
Urban Heat - Research Through Design - Prototype - Water bodies - Thermal sensation
This paper presents five design prototypes for cool urban water environments developed in the 'Really cooling water bodies in cities' (REALCOOL) project. The REALCOOL prototypes address an urgent need: urban water bodies, such as ponds or canals, are often assumed to cool down their surroundings during days with heat stress, whereas recent research shows that this is not always the case and that urban water bodies may actually have warming effects too. There are, however, indications that shading, vaporising water, and proper ventilation can keep water bodies and their surroundings cooler. Yet, it is necessary to explore how these strategies can be optimally combined and how the resulting design guidelines can be communicated to design professionals. The REALCOOL prototypes communicate the spatial layout and biometeorological effects of such combinations and assist design decisions dealing with urban water environments. The micrometeorological simulations with Envi­met showed that the prototypes led to local reductions on daytime PET from 1 °C to 7 °C, upon introducing shade. Water mist and fountains were also cooling solutions. The important role of ventilation was confirmed. The paper discusses and concludes about the use of the prototypes as tools for urban design practice.
Perceptions of Land Tenure Security in Rural China: The Impact of Land Reallocations and Certification
Ren, Guangcheng ; Zhu, Xueqin ; Heerink, Nico ; Feng, Shuyi ; Ierland, Ekko van - \ 2019
Society & Natural Resources 32 (2019)12. - ISSN 0894-1920 - p. 1399 - 1415.
Household perceptions - land certificates - land tenure security - probit model - rural China

Tenure security is commonly recognized as an important factor in stimulating long-term investments in land. Recent studies suggest that a distinction between legal, actual and perceived tenure security needs to be made in analyzing tenure security. This study discusses the relationships between legal, actual and perceived land tenure security in rural China, and empirically examines the impact of actual on perceived land tenure security by applying Probit models to household and village survey data collected in four provinces. Using household expectations about the absence of land reallocations within the next five years as the dependent variable, we find that tenure security is positively affected by the possession of land certificates in villages that periodically reallocated land but not in villages that did not do so. The estimated impact is larger for land certificates issued in the new round of land certification than for land certificates that were issued earlier.

Phytophthora infestans RXLR effectors act in concert at diverse subcellular locations to enhance host colonization
Wang, Shumei ; McLellan, Hazel ; Bukharova, Tatyana ; He, Qin ; Murphy, Fraser ; Shi, Jiayang ; Sun, Shaohui ; Weymers, Pauline van; Ren, Yajuan ; Thilliez, Gaetan ; Wang, Haixia ; Chen, Xinwei ; Engelhardt, Stefan ; Vleeshouwers, Vivianne ; Gilroy, Eleanor M. ; Whisson, Stephen C. ; Hein, Ingo ; Wang, Xiaodan ; Tian, Zhendong ; Birch, Paul R.J. ; Boevink, Petra C. - \ 2019
Journal of Experimental Botany 70 (2019)1. - ISSN 0022-0957 - p. 343 - 356.

Oomycetes such as the potato blight pathogen Phytophthora infestans deliver RXLR effectors into plant cells to manipulate host processes and promote disease. Knowledge of where they localize inside host cells is important in understanding their function. Fifty-two P. infestans RXLR effectors (PiRXLRs) up-regulated during early stages of infection were expressed as fluorescent protein (FP) fusions inside cells of the model host Nicotiana benthamiana. FP-PiRXLR fusions were predominantly nucleo-cytoplasmic, nuclear, or plasma membrane-associated. Some also localized to the endoplasmic reticulum, mitochondria, peroxisomes, or microtubules, suggesting diverse sites of subcellular activity. Seven of the 25 PiRXLRs examined during infection accumulated at sites of haustorium penetration, probably due to co-localization with host target processes; Pi16663 (Avr1), for example, localized to Sec5-associated mobile bodies which showed perihaustorial accumulation. Forty-five FP-RXLR fusions enhanced pathogen leaf colonization when expressed in Nicotiana benthamiana, revealing that their presence was beneficial to infection. Co-expression of PiRXLRs that target and suppress different immune pathways resulted in an additive enhancement of colonization, indicating the potential to study effector combinations using transient expression assays. We provide a broad platform of high confidence P. infestans effector candidates from which to investigate the mechanisms, singly and in combination, by which this pathogen causes disease.

Intercropping potato (Solanum tuberosum L.) with hairy vetch (Vicia villosa) increases water use efficiency in dry conditions
Ren, Jianhong ; Zhang, Lizhen ; Duan, Yu ; Zhang, Jun ; Evers, Jochem B. ; Zhang, Yue ; Su, Zhicheng ; Werf, Wopke van der - \ 2019
Field Crops Research 240 (2019). - ISSN 0378-4290 - p. 168 - 176.
Biomass - Daily water use - Land equivalent ratio (LER) - Water equivalent ratio (WER) - Water saving

Protection from soil erosion and efficient use of water are vital to sustainable dryland potato production in semi-arid regions. Introducing legumes into semi-arid agricultural systems as intercrops improves soil quality due to biological nitrogen fixation and reduced wind erosion as a result of better soil cover, but the consequences of introducing legumes for the water use efficiency of the crop system are less predictable. Here we carried out field experiments from 2014 to 2017 in Inner Mongolia, China. We compared a rotational intercropping system of potato (Solanum tuberosum L.) and hairy vetch (Vicia villosa) with monocultures of potato and hairy vetch and quantified crop yield, water use efficiency and land productivity. While the relative density (the ratio of plant density in intercrop and the density in sole stand) of both crops in the intercropping was 0.5, the average relative yield of the potato over four years was 0.43, but that of the vetch was 0.87, indicating dominance of the vetch in the intercropping system. Land and water equivalent ratios, defined as the area of land or amount of water that would be needed in single cropping to achieve the same yield as in intercropping, averaged to 1.30 and 1.29 over the years, respectively, indicating high relative land and water productivity of potato/hairy vetch intercropping compared to monocultures. Vetch was a stronger competitor for water than potato with a partial water equivalent ratio of 0.83. We conclude that the potato/vetch intercropping system improves land productivity and system level water use efficiency under the rain-fed semi-arid conditions of the study site. These results are useful to optimize cropping systems for regional sustainability with consideration of both arable crop production (potato) and provision of fodder for animal husbandry (vetch).

Effect of fermentation on content, molecule weight distribution and viscosity of β-glucans in oat sourdough
Lu, Jun ; Shan, Lingke ; Xie, Yiting ; Min, Fangfang ; Gao, Jinyan ; Guo, Laichun ; Ren, Changzhong ; Yuan, Juanli ; Gilissen, Luud ; Chen, Hongbing - \ 2019
International Journal of Food Science and Technology 54 (2019)1. - ISSN 0950-5423 - p. 62 - 67.
Fermentation - Lactobacillus plantarum - Oat β-glucan - Sourdough - Viscosity

This study investigated the effect of fermentation on the physicochemical properties of β-glucans in oat sourdough. Sourdoughs were produced from oat using homo-fermentative lactic acid bacteria, Lactobacillus plantarum 22134. The contents of total β-glucan and soluble β-glucan, the molecular weight (MW) of β-glucan and the viscosity of the extracted β-glucans were determined at 0, 4, 8, 10 and 12 h of fermentation. The total β-glucan content decreased from 4.89% to 4.23% after 12 h of fermentation. The soluble β-glucan concentration increased from 1.89% to 2.18% and then decreased to 1.97% after 8 h of fermentation. The content of β-glucans with MW > 105 decreased from 0 to 4 h of fermentation, followed by an increase and then a decrease after 8 h. The oat sourdough fermented for 8 h had high viscosity, which could be more beneficial for health and bread texture quality, especially for gluten-free breads. International Journal of Food Science and Technology

PREVIEW study—Influence of a behavior modification intervention (PREMIT) in over 2300 people with pre-diabetes : Intention, self-efficacy and outcome expectancies during the early phase of a lifestyle intervention
Huttunen-Lenz, Maija ; Hansen, Sylvia ; Christensen, Pia ; Larsen, Thomas Meinert ; Sandø-Pedersen, Finn ; Drummen, Mathijs ; Adam, Tanja C. ; Macdonald, Ian A. ; Taylor, Moira A. ; Martinez, J.A. ; Navas-Carretero, Santiago ; Handjiev, Svetoslav ; Poppitt, Sally D. ; Silvestre, Marta P. ; Fogelholm, Mikael ; Pietiläinen, Kirsi H. ; Brand-Miller, Jennie ; Berendsen, Agnes A.M. ; Raben, Anne ; Schlicht, Wolfgang - \ 2018
Psychology Research and Behavior Management 11 (2018). - ISSN 1179-1578 - p. 383 - 394.
Cognition - Diabetes mellitus - Goals - Habits - Weight loss

Purpose: Onset of type 2 diabetes (T2D) is often gradual and preceded by impaired glucose homeostasis. Lifestyle interventions including weight loss and physical activity may reduce the risk of developing T2D, but adherence to a lifestyle change is challenging. As part of an international T2D prevention trial (PREVIEW), a behavior change intervention supported participants in achieving a healthier diet and physically active lifestyle. Here, our aim was to explore the influence of this behavioral program (PREMIT) on social-cognitive variables during an 8-week weight loss phase. Methods: PREVIEW consisted of an initial weight loss, Phase I, followed by a weight-maintenance, Phase II, for those achieving the 8-week weight loss target of ≥ 8% from initial bodyweight. Overweight and obese (BMI ≥25 kg/m2) individuals aged 25 to 70 years with confirmed pre-diabetes were enrolled. Uni-and multivariate statistical methods were deployed to explore differences in intentions, self-efficacy, and outcome expectancies between those who achieved the target weight loss (“achievers”) and those who did not (“non-achievers”). Results: At the beginning of Phase I, no significant differences in intentions, self-efficacy and outcome expectancies between “achievers” (1,857) and “non-achievers” (163) were found. “Non-achievers” tended to be younger, live with child/ren, and attended the PREMIT sessions less frequently. At the end of Phase I, “achievers” reported higher intentions (healthy eating χ2 (1)=2.57; P <0.008, exercising χ2 (1)=0.66; P <0.008), self-efficacy (F(2; 1970)=10.27, P <0.005), and were more positive about the expected outcomes (F(4; 1968)=11.22, P <0.005). Conclusion: Although statistically significant, effect sizes observed between the two groups were small. Behavior change, however, is multi-determined. Over a period of time, even small differences may make a cumulative effect. Being successful in behavior change requires that the “new” behavior is implemented time after time until it becomes a habit. Therefore, having even slightly higher self-efficacy, positive outcome expectancies and intentions may over time result in considerably improved chances to achieve long-term lifestyle changes.

Haiti technical cold chain dry run : applying distributed ledger technology to connect Haitian mango and avocado producers toforeign markets
Oostewechel, Rene ; Régis, Yves-Laurent ; Brouwers, Jan ; Vogels, Jan ; Smeenk, Anton ; Ren, Xin-Ying - \ 2018
Wageningen : Wageningen Food & Biobased Research (Wageningen Food & Biobased Research report 1838) - ISBN 9789463434706 - 33
This report provides the technical results of a dry run transporting mangoes and avocados from Haiti to the US, Canada and The Netherlands. For both fruits, temperature has been registered from the moment of harvest till arrival at all destinations. Also logistical data related to the planning and preparation of the test, time needed for each step, and quality of fruits has been analysed. After the introduction chapter, technical data are provided for both mango and avocado in the next two chapters, with a concluding last chapter afterwards that provides overall analysis, lessons learned and recommendations. Use of the QR codes has allowed a transparent and digital process where all chain partners have open access to all information. The report presents a block chain test at limited level and actual implementation and scaling of block chain procedures might still need refinement like the longer ripening and/or storage before retail distribution.
Tourism innovation by hundling practices : A genealogy of the 'Zeelandpas' destination card
Derriks, T. ; Duim, V.R. van der; Peters, K.B.M. - \ 2018
In: Theories of Practice in Tourism / James, Laura, Ren, Carina, Halkier, Henrik, Oxxon : Routledge - ISBN 9781138061705 - p. 115 - 132.
This chapter examines the history of the regional tourism destination card and develops a specific and detailed analysis of its development as a 'bundling of practices'. It examines the development of this destination card genealogically by historically following its actors and their actions. The chapter reconstructs how connections between practices have been achieved and how constituent practices have changed accordingly. It first, introduces practice theory, the case and the methods used. Second, it shows how practices were connected and the card was developed by studying the genealogy of this card. The chapter examines the process of creating, realising and implementing a destination card in a Dutch context. It aims to contribute to literature on tourism destination cards by presenting a detailed understanding of its associated processes. The chapter particularly focuses on which 'doings and sayings', rules and materials played an important role in connecting existing practices into this destination card and how this bundling affected existing practices.
The intelligent delivery systems for bioactive compounds in foods : Physicochemical and physiological conditions, absorption mechanisms, obstacles and responsive strategies
Chai, Jingjing ; Jiang, Ping ; Wang, Pengjie ; Jiang, Yumeng ; Li, Dan ; Bao, Weier ; Liu, Bingxue ; Liu, Bin ; Zhao, Liyun ; Norde, Willem ; Yuan, Qipeng ; Ren, Fazheng ; Li, Yuan - \ 2018
Trends in Food Science and Technology 78 (2018). - ISSN 0924-2244 - p. 144 - 154.
Bioaccessibility - Bioactive compounds - Bioavailability - Delivery barriers - Encapsulation - Intelligent delivery systems

Background: Bioactive natural compounds have received considerable attention due to their health benefits, including anti-oxidant, anti-cancer, anti-diabetes and cardiovascular disease-preventing functions. However, the stability of these sensitive compounds can be influenced by unfavourable environmental conditions during processing and storage. In addition, delivery of bioactive compounds via the oral route is restricted by various physiological barriers, including a harsh pH, gastrointestinal enzymes, the mucus layer, and the epithelium. Intelligent delivery systems are a promising method to protect bioactive molecules from degradation and improve their bioavailability. Scope and approach: We have demonstrated the physicochemical and physiological GI conditions. The structural composition of the epithelium and transport mechanisms of bioactives and nanoparticles across the intestinal epithelium were discussed. The effects of enhanced aqueous solubility, stability, bioaccessibility and bioavailability after encapsulation were illustrated. Furthermore, novel intelligent carriers that are responsive to the oral route, pH, enzymes and cell receptors were also discussed. Key findings and conclusions: This comprehensive multidisciplinary review provides useful guidelines for the application of bioactive compounds in the food industry. Intelligent carrier systems are designed to improve the low solubility, poor stability and low permeability of the gastrointestinal tract, and they have the potential to improve oral bioavailability.

Microscopic Origins of Shear Jamming for 2D Frictional Grains
Wang, Dong ; Ren, Jie ; Dijksman, Joshua A. ; Zheng, Hu ; Behringer, Robert P. - \ 2018
Physical Review Letters 120 (2018)20. - ISSN 0031-9007

Shear jamming (SJ) occurs for frictional granular materials with packing fractions φ in φS<φ<φJ0, when the material is subject to shear strain γ starting from a force-free state. Here, φJμ is the isotropic jamming point for particles with a friction coefficient μ. SJ states have mechanically stable anisotropic force networks, e.g., force chains. Here, we investigate the origins of SJ by considering small-scale structures - trimers and branches - whose response to shear leads to SJ. Trimers are any three grains where the two outer grains contact a center one. Branches occur where three or more quasilinear force chain segments intersect. Certain trimers respond to shear by compressing and bending; bending is a nonlinear symmetry-breaking process that can push particles in the dilation direction faster than the affine dilation. We identify these structures in physical experiments on systems of two-dimensional frictional discs, and verify their role in SJ. Trimer bending and branch creation both increase Z above Ziso≃3 needed for jamming 2D frictional grains, and grow the strong force network, leading to SJ.

Characterizing granular networks using topological metrics
Dijksman, Joshua A. ; Kovalcinova, Lenka ; Ren, Jie ; Behringer, Robert P. ; Kramar, Miroslav ; Mischaikow, Konstantin ; Kondic, Lou - \ 2018
Physical Review. E, Statistical nonlinear, and soft matter physics 97 (2018)4. - ISSN 2470-0045
We carry out a direct comparison of experimental and numerical realizations of the exact same granular system as it undergoes shear jamming. We adjust the numerical methods used to optimally represent the experimental settings and outcomes up to microscopic contact force dynamics. Measures presented here range from microscopic through mesoscopic to systemwide characteristics of the system. Topological properties of the mesoscopic force networks provide a key link between microscales and macroscales. We report two main findings: (1) The number of particles in the packing that have at least two contacts is a good predictor for the mechanical state of the system, regardless of strain history and packing density. All measures explored in both experiments and numerics, including stress-tensor-derived measures and contact numbers depend in a universal manner on the fraction of nonrattler particles, fNR. (2) The force network topology also tends to show this universality, yet the shape of the master curve depends much more on the details of the numerical simulations. In particular we show that adding force noise to the numerical data set can significantly alter the topological features in the data. We conclude that both fNR and topological metrics are useful measures to consider when quantifying the state of a granular system.
Data-Driven Modeling of Intracellular Auxin Fluxes Indicates a Dominant Role of the ER in Controlling Nuclear Auxin Uptake
Middleton, Alistair M. ; Bosco, Cristina Dal; Chlap, Phillip ; Bensch, Robert ; Harz, Hartmann ; Ren, Fugang ; Bergmann, Stefan ; Wend, Sabrina ; Weber, Wilfried ; Hayashi, Ken Ichiro ; Zurbriggen, Matias D. ; Uhl, Rainer ; Ronneberger, Olaf ; Palme, Klaus ; Fleck, Christian ; Dovzhenko, Alexander - \ 2018
Cell Reports 22 (2018)11. - ISSN 2211-1247 - p. 3044 - 3057.
auxin - auxin flux - auxin sensor - endoplasmic reticulum - fluorescent aux - mathematical modeling - microscopy - nucleus - protoplasts - single cells
In plants, the phytohormone auxin acts as a master regulator of developmental processes and environmental responses. The best characterized process in the auxin regulatory network occurs at the subcellular scale, wherein auxin mediates signal transduction into transcriptional programs by triggering the degradation of Aux/IAA transcriptional repressor proteins in the nucleus. However, whether and how auxin movement between the nucleus and the surrounding compartments is regulated remain elusive. Using a fluorescent auxin analog, we show that its diffusion into the nucleus is restricted. By combining mathematical modeling with time course assays on auxin-mediated nuclear signaling and quantitative phenotyping in single plant cell systems, we show that ER-to-nucleus auxin flux represents a major subcellular pathway to directly control nuclear auxin levels. Our findings propose that the homeostatically regulated auxin pool in the ER and ER-to-nucleus auxin fluxes underpin auxin-mediated downstream responses in plant cells. Middleton et al. study how the plant phytohormone auxin enters the nucleus by using quantitative phenotyping in single plant cell systems and bespoke mathematical models that relate controlled perturbations to experimentally measurable responses. Their findings show that auxin predominantly enters the nucleus via the endoplasmic reticulum.
The evolution of determinate and indeterminate nodules within the Papilionoideae subfamily
Ren, Guiling - \ 2018
Wageningen University. Promotor(en): T. Bisseling, co-promotor(en): R. Geurts. - Wageningen : Wageningen University - ISBN 9789463432306 - 129

We selected the legume Indigofera argentea for our research. It was collected in the desert of Jizan in Saudi Arabia. We selected this species for two reasons. It is well adapted to heat and drought and therefore it has the potential to study, in the future, mechanisms that confer tolerance to these abiotic stresses. Further, Indigofera represents an early branching lineage within the indigoferoid/milletioid clade. Therefore, Indigofera is a key genus in studying the evolution of nodulation within the Papilionoideae subfamily.

In Chapter 1, a general introduction is given on nitrogen fixing symbiosis of legumes and rhizobia. In this introduction, we focus on the process of nodule initiation and organogenesis. Two main nodule types, determinate and indeterminate nodule, are introduced based on the knowledge of the few well-studied legumes species. Further, terminal differentiation of rhizobia that is induced by NCR peptides of the host is introduced.

In Chapter 2, we characterized the desert legume I. argentea and developed a platform by which future studies on mechanisms controlling abiotic stress become available. We developed an Agrobacterium rhizogenes-mediated root transformation procedure and did a de novo transcriptome assembly using RNA of various organs.

In Chapter 3, about 60 rhizobium strains have been isolated from nodulated I. argentea plants that were collected in the desert. The strains were characterized by 16S sequencing and their nodulation abilities were studied. One of the efficient nodulating Bradyrhizobium strains was selected for further studies.

In Chapter 4, nodule development of Indigofera and Tephrosia species was analysed and described in detail. Species from both genera have an indeterminate growth. However, it was shown that this is not due to a meristem that is formed at the primordium stage, which is the basis of indeterminate growth of IRLC species like Medicago. The indeterminate growth was shown to be due to secondary clusters of dividing infected cells that were formed from nodule parenchyma cells. Therefore, it evolved independently from the indeterminate growth from IRLC species which is controlled by a persistent meristem composed of non-infected cells.

In Chapter 5, it is shown that bacteroids from I. argentea nodules are markedly enlarged as described for IRLC (e.g. Medicago) and Aeschynomene species. This increase in size was correlated with endoreduplication and terminal differentiation. Further, it was shown that in nodules of I. argentea 4 NCR genes are expressed. Therefore it is probable that these terminal differentiation is controlled by the NCR peptides and this evolved independently in the IRLC clade, Aeschynomene and Indigofera.

In Chapter 6, I discuss my results and put them in a broader perspective. I summarize and discuss the determinate and indeterminate nodule evolution in the Papilionoideae subfamily.

We have shown in Chapter 4 that Indigofera and Tephrosia species have a nodule development that is very similar to that of determinate nodules and their indeterminate growth is due to the formation of secondary clusters of dividing cells. Species from other clades of the Papilionoideae subfamily were analyzed. Based on these analyses, I conclude that the ancestor of the Papilionoideae subfamily formed determinate nodules that had the ability to form secondary clusters of dividing cells. Further, NCR-triggered bacteroid evolution in the Papilionoideae subfamily is discussed.

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