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There are important differences between performing research in geriatric medicine and in other fields of medicine. Geriatric research requires specific preconditions in all phases of conducting research due to the heterogeneity among geriatric patients and the high prevalence of multi-morbidity, often resulting in impaired physical, psychological and social performances. This paper discusses issues important for successful recruitment and selection of subjects, the informed consent procedure and selection of appropriate research designs and research instruments in geriatric research. The recommendations given are based on a review of relevant literature and own research experiences in the 'Nijmegen geriatric research programme on Brain Failure'. [ABSTRACT FROM AUTHOR]

Caenorhabditis elegans CEP-1 activates germline apoptosis in response to genotoxic stress, similar to its mammalian counterpart, tumor suppressor p53. In mammals, there are three p53 family members (p53, p63, and p73) that activate and repress many distinct and overlapping sets of genes, revealing a complex transcriptional regulatory network. Because CEP-1 is the sole p53 family member in C. elegans, analysis of this network is greatly simplified in this organism. We found that CEP-1 functions during normal development in the absence of stress to repress many (331) genes and activate only a few (28) genes. In response to genotoxic stress, 1394 genes are activated and 942 are repressed, many of which contain p53-binding sites. Comparison of the CEP-1 transcriptional network with transcriptional targets of the human p53 family reveals considerable overlap between CEP-1-regulated genes and homologues regulated by human p63 and p53, suggesting a composite p53/p63 action for CEP-1. We found that phg-1, the C. elegans Gas1 (growth arrest-specific 1) homologue, is activated by CEP-1 and is a negative regulator of cell proliferation in the germline in response to genotoxic stress. Further, we find that CEP-1 and PHG-1 mediate the decreased developmental rate and embryonic viability of mutations in the clk-2/TEL2 gene, which regulates lifespan and checkpoint responses.Cell Death and Differentiation (2007) 14, 662–670. doi:10.1038/sj.cdd.4402075; published online 22 December 2006 [ABSTRACT FROM AUTHOR]

Deals with a study which measured whole-plant gas exchange on rooted cuttings of Girard's Pleasant White azaleas. Materials and methods; Results; Discussion.

Water relations of cotton (Gossypium hirsutum L.) fruits have received less attention than those of leaves, although crop water status has an important influence on fruit physiology. This study was conducted to describe diurnal changes in the water relations of cotton fruits and sub-tending leaves. Young, expanding fruits and full-sized fruits were compared because of previously reported changes in xylem maturity with ontogeny. Diurnal changes in relative water content were greater in leaves than in the capsule walls of fruits. The capsule walls of young fruits had a higher relative water content than sub- tending leaves, and water content was lower in full-sized (87%) than in expanding (92%) fruits. Water potentials of subtending leaves were always approximately 0.3 MPa lower than those of capsule walls. Water potential gradients favoured passive water flow from young fruits to branches, but water potentials of branches and the capsule walls of full-sized fruits were similar (-0.7 MPa). Water potential gradients were consistent throughout the day. These results indicate that xylem transport to young fruits is unlikely, but may occur in older fruits. [ABSTRACT FROM AUTHOR]

Different succulent plants have been shown to exhibit varying degrees of crassulacean acid metabolism (CAM). This variation has not been consistently shown to relate to water use efficiency (WUE) by these species. This raises fundamental questions about the ecophysiological implications of switching between C3 photosynthesis and CAM metabolism. More information is also needed for Sedum species that utilize CAM to varying degrees on green roofs so that plant water use can be included in water balance equations that predict green roof performance. We monitored carbon dioxide exchange and water use by two common green roof species, Sedum album and Sedum kamtschaticum, for three weeks without water under strictly controlled environmental conditions in order to (1) compare daily carbon gain, rates of evapotranspiration (ET), and WUE for these two species and (2) assess the effect of CAM cycling on WUE with increasing drought for entire plant stands. Under similar environmental conditions, S. album and S. kamtschaticum canopies exhibited CAM metabolism to different extents with different ecophysiological consequences. S. kamtschaticum exhibited C3 photosynthesis for the first 14 days without water and outperformed S. album in terms of carbon gain and WUE above a volumetric water content (VWC) of 0.08m3m−3. S. album was the more drought tolerant species under the conditions of this experiment, gaining at least as much carbon and using water more efficiently at VWC below 0.08m3m−3. By switching from C3 to CAM at lower VWC, S. kamtschaticum had an overall greater WUE even though this species used as much if not more water overall compared to S. album. These data further support suggestions that a major adaptive function of CAM is to prolong plant-available water while maintaining a consistent, albeit low level of carbon gain. These findings also demonstrate why Sedum species should be treated independently of each other when considered in green roof designs. [ABSTRACT FROM AUTHOR]

Purpose: Normal tissue complication probability (NTCP) models can be used to estimate the risk of radiation pneumonitis (RP). The aim of this study was to externally validate the most frequently used prediction models for RP, i.e., the QUANTEC and APPELT models, in a large cohort of lung cancer patients treated with IMRT or VMAT. [1-2] METHODS AND MATERIALS: This prospective cohort study, included lung cancer patients treated between 2013 and 2018. A closed testing procedure was performed to test the need for model updating. To improve model performance, modification or removal of variables was considered. Performance measures included tests for goodness of fit, discrimination, and calibration., Results: In this cohort of 612 patients, the incidence of RP ≥ grade 2 was 14.5%. For the QUANTEC-model, recalibration was recommended which resulted in a revised intercept and adjusted regression coefficient (from 0.126 to 0.224) of the mean lung dose (MLD),. The APPELT-model needed revision including model updating with modification and elimination of variables. After revision, the New RP-model included the following predictors (and regression coefficients): MLD (B = 0.250), age (B = 0.049, and smoking status (B = 0.902). The discrimination of the updated APPELT-model was higher compared to the recalibrated QUANTEC-model (AUC: 0.79 vs. 0.73)., Conclusions: This study demonstrated that both the QUANTEC- and APPELT-model needed revision. Next to changes of the intercept and regression coefficients, the APPELT model improved further by model updating and performed better than the recalibrated QUANTEC model. This New RP-model is widely applicable containing non-tumour site specific variables, which can easily be collected., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 The Author(s). Published by Elsevier B.V. All rights reserved.)

This feature issue highlights the latest developments in laser-based sensing and free space communications. In total, 15 papers were published in Applied Optics, including an invited review paper that celebrates the legacy of David L. Fried.