Quinoa: een gewas voor de toekomst?

Voor de biologische landbouw is er behoefte aan nieuwe voedergewassen die als eiwitbron in het rantsoen kunnen worden opgenomen en waarmee de input van stikstof in het productiesysteem wordt vergroot

Quinoa-GPS in het rantsoen voor melkkoeien

Om deze leemte op te vullen is een voederproef uitgevoerd waarin de effecten van het gedeeltelijk vervangen van gras/klaverkuil door quinoa-GPS zijn onderzocht

Onderzoek naar inkuilverliezen bij snijmais

Voor het bepalen van het tijdstip waarop de maximale drogestof- en voederwaardeopbrengst wordt bereikt zal dus rekening moeten worden gehouden met deze verliezen

The effect of walking speed on quality of gait in older adults

Background: Gait quality characteristics can contribute to the identification of individuals at risk of falls. Since older adults with high fall risk tend to walk slower than older adults with a lower fall risk, walking speed may underlie differences in gait quality characteristics. Research question: How does walking speed affect gait quality characteristics in older people? Methods: We investigated the effect of walking speed on gait characteristics in 11 older adults (aged 69.6 ± 4.1 years). Trunk accelerations (Dynaport MoveMonitor) were recorded during 5 min of treadmill walking at four different speeds. From these trunk accelerations we calculated step frequency, root mean square, harmonic ratio, index of harmonicity, sample entropy and logarithmic divergence rate per stride. Results: Our results showed that all gait characteristics were affected by walking speed, except for sample entropy in antero-posterior (AP) direction. An increase in walking speed resulted in a higher step frequency, higher standard deviation, more symmetric gait, more smooth vertical (VT) accelerations, less smooth accelerations in medio-lateral (ML) and AP directions, less regular dynamics in ML direction, more regular dynamics in VT direction, and a more stable gait pattern overall. Significance: These findings suggest that, within a range of 0.5–1.4 m/s, a lower walking speed results in a lower gait quality, which may underlie differences in gait quality between older fallers and non-fallers

Duurzaam bodembeheer maïs: Maïs en Bodem jaarrapport 2016.

Hoe kunnen veetelers met minder input meer resultaten halen bij snijmaïsteelt? Dat is de centrale vraag van het project “Duurzaam bodembeheer maïs” (BO-31.03-001-003). Veel melkveehouderijbedrijven telen snijmaïs, een gemakkelijk te telen ruwvoergewas met een goede productie van constante hoge kwaliteit. Als zetmeelbron met een ruime energie/eiwitverhouding past het goed in het runderdieet, naast gras en graskuil. De maïsteelt kan echter nadelige effecten hebben voor de bodem door gewasbeschermingsmiddelen en het uit- en afspoelen van nutriënten. Wageningen UR en het Louis Bolk Instituut onderzoeken in opdracht van het ministerie van EZ duurzame en praktisch haalbare verbeteringen en vernieuwingen. Teeltsystemen die zorgen voor een gezonde bodem worden daarbij gezien als sleutel tot duurzame teelt. Op drie locaties worden diverse teeltsystemen vergeleken in meerjarige proeven uitgevoerd op zand- en kleigrond. Daarbij wordt onder andere gekeken naar opbrengst, onkruiddruk, bodemstructuur, aanwezigheid van regenwormen, indringingsweerstand, waterinfiltratie, stikstofdynamiek en economische aspecten. Er zijn in eerste aanleg tevens methoden beproefd die specifiek voor biologische landbouw interessant zijn; Deze kennis wordt vervolgens doorgegeven aan de praktijk middels o.a. de beslisboom snijmaïs, een instrument om praktische kennis naar veetelers en erfbezoekers te brengen. De resultaten uit het vijfde projectjaar (2016) worden in deze rapportage beschreven

Modeling hospital infrastructure by optimizing quality, accessibility and efficiency via a mixed integer programming model

BACKGROUND: The majority of curative health care is organized in hospitals. As in most other countries, the current 94 hospital locations in the Netherlands offer almost all treatments, ranging from rather basic to very complex care. Recent studies show that concentration of care can lead to substantial quality improvements for complex conditions and that dispersion of care for chronic conditions may increase quality of care. In previous studies on allocation of hospital infrastructure, the allocation is usually only based on accessibility and/or efficiency of hospital care. In this paper, we explore the possibilities to include a quality function in the objective function, to give global directions to how the ‘optimal’ hospital infrastructure would be in the Dutch context. METHODS: To create optimal societal value we have used a mathematical mixed integer programming (MIP) model that balances quality, efficiency and accessibility of care for 30 ICD-9 diagnosis groups. Typical aspects that are taken into account are the volume-outcome relationship, the maximum accepted travel times for diagnosis groups that may need emergency treatment and the minimum use of facilities. RESULTS: The optimal number of hospital locations per diagnosis group varies from 12-14 locations for diagnosis groups which have a strong volume-outcome relationship, such as neoplasms, to 150 locations for chronic diagnosis groups such as diabetes and chronic obstructive pulmonary disease (COPD). CONCLUSIONS: In conclusion, our study shows a new approach for allocating hospital infrastructure over a country or certain region that includes quality of care in relation to volume per provider that can be used in various countries or regions. In addition, our model shows that within the Dutch context chronic care may be too concentrated and complex and/or acute care may be too dispersed. Our approach can relatively easily be adopted towards other countries or regions and is very suitable to perform a ‘what-if’ analysis

Characteristics of daily life gait in fall and non fall-prone stroke survivors and controls

BACKGROUND: Falls in stroke survivors can lead to serious injuries and medical costs. Fall risk in older adults can be predicted based on gait characteristics measured in daily life. Given the different gait patterns that stroke survivors exhibit it is unclear whether a similar fall-prediction model could be used in this group. Therefore the main purpose of this study was to examine whether fall-prediction models that have been used in older adults can also be used in a population of stroke survivors, or if modifications are needed, either in the cut-off values of such models, or in the gait characteristics of interest. METHODS: This study investigated gait characteristics by assessing accelerations of the lower back measured during seven consecutive days in 31 non fall-prone stroke survivors, 25 fall-prone stroke survivors, 20 neurologically intact fall-prone older adults and 30 non fall-prone older adults. We created a binary logistic regression model to assess the ability of predicting falls for each gait characteristic. We included health status and the interaction between health status (stroke survivors versus older adults) and gait characteristic in the model. RESULTS: We found four significant interactions between gait characteristics and health status. Furthermore we found another four gait characteristics that had similar predictive capacity in both stroke survivors and older adults. CONCLUSION: The interactions between gait characteristics and health status indicate that gait characteristics are differently associated with fall history between stroke survivors and older adults. Thus specific models are needed to predict fall risk in stroke survivors