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Forage maize (Zea mays L.) is often grown year after year on the same land on many intensive dairy farms in north-west Europe. This results in agronomical problems such as weed resistance and decline of soil quality, which may be solved by ley-arable farming. In the current study, forage maize was grown at different nitrogen (N) fertilization levels for 3 years on permanent arable land and on temporary arable land after ploughing out different types of grass–clover swards. Swards differed in management (grazing or cutting) and age (temporary or permanent). Maize yield and soil residual mineral N content were measured after the maize harvest. There was no effect on maize yield of the management of ploughed-out grass–clover swards but a clear effect of the age of grass–clover swards. The N fertilizer replacement value (NFRV) of all ploughed grass–clover swards was >170 kg N/ha in the first year after ploughing. In the third year after ploughing, NFRV of the permanent sward still exceeded 200 kg N/ha, whereas that of the temporary swards decreased to 30 kg N/ha on average. Soil residual nitrate (NO3−) remained below the local, legal threshold of 90 kg NO3− N/ha except for the ploughed-out permanent sward in the third year after ploughing (166 kg NO3− N/ha). The current study highlights the potential of forage maize – ley rotations in saving fertilizer N. This is beneficial both for the environment and for the profitability of dairy production in north-western Europe.
Introduction of biofortified cassava as school lunch can increase vitamin A intake, but may increase risk of other deficiencies due to poor nutrient profile of cassava. We assessed the potential effect of introducing a yellow cassava-based school lunch combined with additional food-based recommendations (FBR) on vitamin A and overall nutrient adequacy using Optifood (linear programming tool).
Cross-sectional study to assess dietary intakes (24 h recall) and derive model parameters (list of foods consumed, median serving sizes, food and food (sub)group frequency distributions, food cost). Three scenarios were modelled, namely daily diet including: (i) no school lunch; (ii) standard 5d school lunch with maize/beans; and (iii) 5d school lunch with yellow cassava. Each scenario and scenario 3 with additional FBR were assessed on overall nutrient adequacy using recommended nutrient intakes (RNI).
Primary-school children (n 150) aged 7–9 years.
Best food pattern of yellow cassava-based lunch scenario achieved 100 % RNI for six nutrients compared with no lunch (three nutrients) or standard lunch (five nutrients) scenario. FBR with yellow cassava and including small dried fish improved nutrient adequacy, but could not ensure adequate intake of fat (52 % of average requirement), riboflavin (50 % RNI), folate (59 % RNI) and vitamin A (49 % RNI).
Introduction of yellow cassava-based school lunch complemented with FBR potentially improved vitamin A adequacy, but alternative interventions are needed to ensure dietary adequacy. Optifood is useful to assess potential contribution of a biofortified crop to nutrient adequacy and to develop additional FBR to address remaining nutrient gaps.
Objectives: In complex real life situations, memories for temporal and spatial information are naturally linked since sequential events coincide in time and space. Whether this connection is inseparable or instead whether these processes are functionally dissociable was investigated in this patient study. Methods: Spatial object-location and temporal order memory tasks were administered to 36 stroke patients and 44 healthy control participants. Results: On group level, patients with a stroke in the left hemisphere performed worse on temporal order memory, compared to the control participants. On individual level, using a multiple case-study approach, a clear pattern of dissociations was found between memory for temporal and for spatial features. Conclusions: These findings indicate that location and temporal order memory contain functionally separable processes. This adds to our understanding of how context information is processed in human memory. (JINS, 2017, 23, 421–430)
Supplementation with n-3 fatty acids may improve long-term outcomes of renal transplant recipients (RTR). Recent evidence suggests that EPA and DHA have different outcomes compared with α-linolenic acid (ALA). We examined the prospective associations of EPA–DHA and ALA intakes with graft failure and all-cause mortality in 637 RTR. During 3·1 years (interquartile range 2·7, 3·8) of follow-up, forty-one developed graft failure and sixty-seven died. In age- and sex-adjusted analyses, EPA–DHA and ALA intakes were not associated with graft failure. EPA–DHA intake was not significantly associated with mortality (hazard ratio (HR) 0·79; 95% CI 0·54, 1·15 per 0·1 energy% difference). ALA intake was significantly associated with mortality (HR 1·17; 95% CI 1·04, 1·31 per 0·1 energy% difference). This association remained following adjustments for BMI, proteinuria and intakes of fat, carbohydrate and protein. RTR in the highest tertile of ALA intake exhibited about 2-fold higher mortality risk (HR 2·21; 95% CI 1·23, 3·97) compared with the lowest tertile. In conclusion, ALA intake may be associated with increased mortality in RTR. Future RCT are needed to confirm these results.
Current ultra-high-risk (UHR) criteria appear insufficient to predict imminent onset of first-episode psychosis, as a meta-analysis showed that about 20% of patients have a psychotic outcome after 2 years. Therefore, we aimed to develop a stage-dependent predictive model in UHR individuals who were seeking help for co-morbid disorders.
Baseline data on symptomatology, and environmental and psychological factors of 185 UHR patients (aged 14–35 years) participating in the Dutch Early Detection and Intervention Evaluation study were analysed with Cox proportional hazard analyses.
At 18 months, the overall transition rate was 17.3%. The final predictor model included five variables: observed blunted affect [hazard ratio (HR) 3.39, 95% confidence interval (CI) 1.56–7.35, p < 0.001], subjective complaints of impaired motor function (HR 5.88, 95% CI 1.21–6.10, p = 0.02), beliefs about social marginalization (HR 2.76, 95% CI 1.14–6.72, p = 0.03), decline in social functioning (HR 1.10, 95% CI 1.01–1.17, p = 0.03), and distress associated with suspiciousness (HR 1.02, 95% CI 1.00–1.03, p = 0.01). The positive predictive value of the model was 80.0%. The resulting prognostic index stratified the general risk into three risk classes with significantly different survival curves. In the highest risk class, transition to psychosis emerged on average ⩾8 months earlier than in the lowest risk class.
Predicting a first-episode psychosis in help-seeking UHR patients was improved using a stage-dependent prognostic model including negative psychotic symptoms (observed flattened affect, subjective impaired motor functioning), impaired social functioning and distress associated with suspiciousness. Treatment intensity may be stratified and personalized using the risk stratification.
In Palestine, Syria, the provinces of Asia Minor, Armenia, Georgia, and Persia, though Mohammedan countries, there are many thousands of Jews, and many thousands of Christians, at least in name. But the whole mingled population is in a state of deplorable ignorance and degradation, – destitute of the means of divine knowledge, and bewildered with vain imaginations and strong delusions.
Tricyclic antidepressants (TCAs) and selective serotonin reuptake inhibitors (SSRIs) may be associated with lower heart rate variability (HRV), a condition associated with increased mortality risk. We aimed to investigate the association between TCAs, SSRIs and HRV in a population-based study.
In the prospective Rotterdam Study cohort, up to five electrocardiograms (ECGs) per participant were recorded (1991–2012). Two HRV variables were studied based on 10-s ECG recordings: standard deviation of normal-to-normal RR intervals (SDNN) and root mean square of successive RR interval differences (RMSSD). We compared the HRV on ECGs recorded during use of antidepressants with the HRV on ECGs recorded during non-use of any antidepressant. Additionally, we analysed the change in HRV on consecutive ECGs. Those who started or stopped using antidepressants before the second ECG were compared with non-users on two ECGs.
We included 23 647 ECGs from 11 729 participants (59% women, mean age 64.6 years at baseline). Compared to ECGs recorded during non-use of antidepressants (n = 22 971), SDNN and RMSSD were lower in ECGs recorded during use of TCAs (n = 296) and SSRIs (n = 380). Participants who started using TCAs before the second ECG had a decrease in HRV and those who stopped had an increase in HRV compared to consistent non-users (p < 0.001). Starting or stopping SSRIs was not associated with HRV changes.
TCAs were associated with a lower HRV in all analyses, indicating a real drug effect. For SSRIs the results are mixed, indicating a weaker association, possibly due to other factors.
Previous research has established the relationship between cannabis use and psychotic disorders. Whether cannabis use is related to transition to psychosis in patients at ultra-high risk (UHR) for psychosis remains unclear. The present study aimed to review the existing evidence on the association between cannabis use and transition to psychosis in UHR samples.
A search of PsychInfo, Embase and Medline was conducted from 1996 to August 2015. The search yielded 5559 potentially relevant articles that were selected on title and abstract. Subsequently 36 articles were screened on full text for eligibility. Two random-effects meta-analyses were performed. First, we compared transition rates to psychosis of UHR individuals with lifetime cannabis use with non-cannabis-using UHR individuals. Second, we compared transition rates of UHR individuals with a current DSM-IV cannabis abuse or dependence diagnosis with lifetime users and non-using UHR individuals.
We found seven prospective studies reporting on lifetime cannabis use in UHR subjects (n = 1171). Of these studies, five also examined current cannabis abuse or dependence. Lifetime cannabis use was not significantly associated with transition to psychosis [odds ratio (OR) 1.14, 95% confidence interval (CI) 0.856–1.524, p = 0.37]. A second meta-analysis yielded an OR of 1.75 (95% CI 1.135–2.710, p = 0.01), indicating a significant association between current cannabis abuse or dependence and transition to psychosis.
Our results show that cannabis use was only predictive of transition to psychosis in those who met criteria for cannabis abuse or dependence, tentatively suggesting a dose–response relationship between current cannabis use and transition to psychosis.
Severe depression can be a life-threatening disorder, especially in
elderly patients. A fast-acting treatment is crucial for this group.
Electroconvulsive therapy (ECT) may work faster than medication.
To compare the speed of remission using ECT v.
medication in elderly in-patients.
The speed of remission in in-patients with a DSM-IV diagnosis of major
depression (baseline MADRS score $20) was compared between 47
participants (mean age 74.0 years, s.d. = 7.4) from an ECT randomised
controlled trial (RCT) and 81 participants (mean age 72.2 years, s.d. =
7.6) from a medication RCT (nortriptyline v.
Mean time to remission was 3.1 weeks (s.d. = 1.1) for the ECT group and
4.0 weeks (s.d. = 1.0) for the medication group; the adjusted hazard
ratio for remission within 5 weeks (ECT v. medication)
was 3.4 (95% CI 1.9–6.2).
Considering the substantially higher speed of remission, ECT deserves a
more prominent position in the treatment of elderly patients with severe
Hypertension is highly prevalent among renal transplant recipients (RTR) and a risk factor for graft failure and cardiovascular events. Protein intake has been claimed to affect blood pressure (BP) in the general population and may affect renal function. We examined the association of dietary protein with BP and renal function in RTR. We included 625 RTR (age 53 (sd 13) years; 57 % male). Protein intake was assessed with a FFQ, differentiating between animal and plant protein. BP was measured according to a strict protocol. Creatinine clearance and albuminuria were measured as renal parameters. Protein intake was 83 (sd 12) g/d, of which 63 % derived from animal sources. BP was 136 (sd 17) mmHg systolic (SBP) and 83 (sd 11) mmHg diastolic (DBP). Creatinine clearance was 66 (sd 26) ml/min; albuminuria 41 (10–178) mg/24 h. An inverse, though statistically insignificant, association was found between the total protein intake and both SBP (β = − 2·22 mmHg per sd, P= 0·07) and DBP (β = − 0·48 mmHg per sd, P= 0·5). Protein intake was not associated with creatinine clearance. Although albuminuria was slightly higher in the highest tertile of animal protein intake compared with the lowest tertile (66 v. 33 mg/d, respectively, P= 0·03), linear regression analyses did not reveal significant associations between dietary protein and albuminuria. Protein intake exceeded the current recommendations. Nevertheless, within the range of protein intake in our RTR population, we found no evidence for an association of dietary protein with BP and renal function. Intervention studies focusing on different protein types are warranted to clarify their effect on BP and renal function in RTR.
A decline in everyday cognitive functioning is important for diagnosing dementia. Informant questionnaires, such as the informant questionnaire on cognitive decline in the elderly (IQCODE), are used to measure this. Previously, conflicting results on the IQCODEs ability to discriminate between Alzheimer's disease (AD), mild cognitive impairment (MCI), and cognitively healthy elderly were found. We aim to investigate whether specific groups of items are more useful than others in discriminating between these patient groups. Informants of 180 AD, 59 MCI, and 89 patients with subjective memory complaints (SMC) completed the IQCODE. To investigate the grouping of questionnaire items, we used a two-dimensional graded response model (GRM).The association between IQCODE, age, gender, education, and diagnosis was modeled using structural equation modeling. The GRM with two groups of items fitted better than the unidimensional model. However, the high correlation between the dimensions (r=.90) suggested unidimensionality. The structural model showed that the IQCODE was able to differentiate between all patient groups. The IQCODE can be considered as unidimensional and as a useful addition to diagnostic screening in a memory clinic setting, as it was able to distinguish between AD, MCI, and SMC and was not influenced by gender or education. (JINS, 2011, 17, 674–681)
Mercuric iodide (HgI2) single crystals deposited with semitransparent Pd, Al and Ag contacts were studied by thermally stimulated current spectroscopy (TSC). Distinct differences were found among spectra obtained friom samples withdifferentmetal contacts, indicating that interactions between the metal contacts and mercuric iodide substrates have strong effects on the deep defect levels in mercuric iodide. The activation energies of some of these defect levels were estimated bytaking TSC spectra with different heating rates. In addition, a pyroelectric effect was observed in Ag-contactedsamplesbythermally stimulated depolarization current technique (TSDC). The implications of these results in device applicationsof mercuric iodide are discussed.
Mercuric iodide (HgI2) single crystals deposited with transparent indium-tin-oxide (ITO), and semitransparent gold and nickel contacts were investigated by thermally stimulated current spectroscopy (TSC). The differences in the TSC spectra from these samples indicate that the defect structure in HgI2 may be modified by the contact material. These defects act as carrier traps and have strong implications in the application of HgI2 nuclear detectors. A method of numerical analysis was developed to extract information such as carrier trap activation energy, capture cross-section, and trap concentration-lifetime product from the TSC measurements.
In the fabrication of mercuric iodide room temperature radiation detectors, as in any semiconductor process, the quality of the final device can be very sensitive to the details of the processing steps. Each processing step can either reduce the intrinsic defects and those extrinsic defects introduced by earlier steps, or it can introduce new defects. In mercuric iodide these defects can act as trapping and recombination centers, thereby degrading immediate device performance or leading to long-term reliability problems. With careful study and monitoring of each step, the process can be modified to improve the end product. In this work we used several techniques to study processing steps and their effects. Photoluminescence spectroscopy and photoionization revealed defects introduced during processing. One critical step is the formation of electrical contacts, as both the material choice and deposition method have an impact. Four point probe sheet resistance methods were used to characterize the loss of material from the contact as it reacted with or moved into the bulk semiconductor. Ellipsometry was used to characterize the intrinsic optical functions of the material, and to study the effects of surface aging on these functions. Results from this work provide suggestions for the modification and monitoring of the detector fabrication process.
A short review will be given of the methods by which mercuric iodide is prepared and purified to obtain material suitable for the growth of single crystals. The method used in our laboratory to grow single crystals up to 1,000 grams in weight from the vapor will be discussed. The effects of gravity on the growth process will be described.
A crystal growth system suitable for operation in the reduced gravity environment of space was designed, and crystal growth experiments were performed during the flights of Spacelab 3 (April 1985) and the International Microgravity Laboratory (IML-1) (January 1992). The structural quality and electronic properties of the ground-based and spacegrown crystals were compared, and the results will be presented.
The Ion Micro-Analysis Group (IMAG) in Livermore conducts quantitative trace elemental analysis with PIXE and depth profiling with IBS using an MeV ion microbeam. The system has the capability to produce two-dimensional trace element and IBS images. PIXE analyses have been conducted on HgI2 and PbI2 crystals and detector materials in order to identify and quantify near surface trace contaminants. IBS measurements have been conducted to investigate elemental depth distributions in various materials. The results of measurements on several different samples are reported and a discussion of factors affecting quantitative in vacuo microanalysis of these materials is presented.
The incorporation of extrinsic defects into mercuric iodide substrates during detector fabrication can be extremely detrimental to device performance. In particular, extrinsic defects can act as trapping and recombination centers, and they can reduce charge collection efficiencies, decrease gt product, or contribute to polarization effects in nuclear detectors. In this paper we present results of processing, photoluminescence, and electromigration experiments that clearly show that extrinsic defects can be incorporated in mercuric iodide during detector fabrication. By observing the luminescence features characteristic of Cu and Ag in mercuric iodide, we show that both these materials are taken up by mercuric iodide crystals during etching with KI if the etching solution is contaminated with these elements. The migration of material from contacts into the crystal, as shown by resistance measurements, is also presented. We infer from this work that other defects which are detrimental to device performance may also be incorporated in mercuric iodide if insufficient care is taken during device fabrication. Suggestions are therefore made as to some of the precautions that must be taken in order to realize the highest quality detectors.
Computer modeling is used as a tool for determining current matching in hydrogenated amorphous silicon (a-Si:H) alloy tandem cells on textured substrates. The increasing complexity of a-Si:H based solar cells requires continuous extending and testing of the computer models which are used for their simulation. To take light scattering at the textured interfaces of the cell into account we developed a multi-rough-interface optical model GENPR02 which was used for calculating the absorption profiles in the solar cells. The results of a sensitivity study of the parameters of this optical model such as the scattering coefficients of the reflected and transmitted light and the dependence of scattered light on the in-going and out-going angle are presented. In order to simulate multi-junction solar cell as a complete device we implemented a novel model for tunnel/recombination junction (TRJ), which combines the trap assisted tunneling and enhanced carrier transport in the high field region of the TRJ.
The current matching conditions were determined both for a-Si:H and a-SiGe:H bottom cells, while the top cell was an a-Si:H cell. We investigated the influence of light scattering at the textured interfaces and of the thickness of the intrinsic layer of the bottom cell on the optimal ratio (i2/i1) between the thicknesses of the bottom (i2) and top (il) intrinsic layers in the current-matched cell. The results show that increasing amount of scattering at the textured interfaces leads to higher efficiencies and lower ratio (i2/i1) in the current-matched cell. The use of a-SiGe:H material in the bottom cell leads to higher efficiency and 3 to 4 times lower i2/i1 ratio than in case of a-Si:H/a-Si:H cells.
Single crystal sections of HgI2 (about 1 cm thick) have been evaluated for charge carrier transport properties. Using these thick detector structures, surface effects produced during fabrication are reduced, enhancing the bulk property characteristics. The standard time-of-flight method was used to determine electron and hole mobilities. Lifetime measurements for electrons and holes were made by direct observation of the carrier decay where crystal transit times were long compared to lifetimes. Nonlinear charge carrier velocities have been observed during mobility measurements. These nonlinearities impair a partial charge collection technique [1,2,3] for spectra generation taken with thick detectors while having a lesser effect on the standard full charge collection approach. Partial charge collection methods have produced greater peak efficiencies than full charge collection, and investigations of crystal properties are being used to enhance this method.