Diversity and composition of the microbiome associated with eggs of the Southern green stinkbug, Nezara viridula (Hemiptera: Pentatomidae)

Although microbial communities of insects from larval to adult stage have been increasingly investigated in recent years, little is still known about the diversity and composition of egg-associated microbiomes. In this study, we used high-throughput amplicon sequencing and quantitative PCR to get a better understanding of the microbiome of insect eggs and how they are established using the Southern green stinkbug Nezara viridula (L.) (Hemiptera: Pentatomidae) as a study object. First, to determine the bacterial community composition, egg masses from two natural populations in Belgium and Italy were examined. Subsequently, microbial community establishment was assessed by studying stinkbug eggs of different ages obtained from laboratory strains (unlaid eggs collected from the ovaries, eggs less than 24 h old, and eggs collected 4 days after oviposition). Both the external and internal egg-associated microbiomes were analyzed by investigating egg washes and surface-sterilized washed eggs, respectively. Eggs from the ovaries were completely devoid of bacteria, indicating that egg-associated bacteria were deposited on the eggs during or after oviposition. The bacterial diversity of deposited eggs was very low, with on average 6.1 zero-radius operational taxonomic units (zOTUs) in the external microbiome and 1.2 zOTUs in internal samples of egg masses collected from the field. Bacterial community composition and density did not change significantly over time, suggesting limited bacterial growth. A Pantoea-like symbiont previously found in the midgut of N. viridula was found in every sample and generally occurred at high relative and absolute densities, especially in the internal egg samples. Additionally, some eggs harbored a Sodalis symbiont, which has previously been found in the abdomen of several insects, but so far not in N. viridula populations. We conclude that the egg-associated bacterial microbiome of N. viridula is species-poor and dominated by a few symbionts, particularly the species-specific obligate Pantoea-like symbiont

Excite-Probe Determination of the Intersubband Lifetime in Wide Gaas/Algaas Quantum-Wells Using a Far-Infrared Free-Electron Laser

A direct excite-probe semiconductor lifetime determination in the picosecond regime has been made for the first time in the far infrared. We have used an RF-linac-pumped free-electron laser to determine the relaxation rate associated with intersubband absorption in GaAs/AlGaAs quantum wells having a subband separation smaller than the optical phonon energy. The measurement yields a relaxation lifetime of 40 +/- 5 ps. This is compared with a variety of other results obtained with less direct techniques

Evaluating quality of life in frailty: applicability and clinimetric properties of the SarQoL ®

peer reviewedBACKGROUND: The SarQoL® questionnaire was specifically designed to measure quality of life (QoL) in sarcopenia. Frailty and sarcopenia have areas of overlap, notably weak muscle strength and slow gait speed, which may mean that the SarQoL could provide a measure of QoL in frailty. This study aimed to evaluate the clinimetric properties of the SarQoL questionnaire in physical frailty using the Fried criteria. METHODS: Analyses were carried out on data from the Sarcopenia and Physical impairment with advancing Age study. Frailty was assessed with the Fried criteria and QoL with the SarQoL, the Short-Form 36-Item, and the EuroQoL 5-Dimension (EQ-5D) questionnaires. We evaluated discriminative power (with the Kruskal-Wallis analysis of variance test), internal consistency (with Cronbach's alpha), construct validity (through hypotheses testing), test-retest reliability (with the intraclass correlation coefficient), measurement error (calculating standard error of measurement and smallest detectable change), and responsiveness (through hypotheses testing and standardized response mean). RESULTS: In total, 382 participants were included for the validation and 117 for the responsiveness evaluation. They had a median age of 73 (69-79) years, took 5 (3-8) drugs, and had 4 (3-5) co-morbidities. There were more women (n = 223; 58.4%) than men and, in total, 172 (45%) robust, 167 (44%) pre-frail, and 43 (11%) frail participants. Discriminative power was confirmed when significantly lower (P < 0.001) overall SarQoL scores, and thus also worse QoL, were observed between robust [77.1 (64.35-85.90)], pre-frail [62.54 (53.33-69.57)], and frail [49.99 (40.45-56.06)] participants. Six of the SarQoL domains performed likewise, with significantly lower scores according to frailty status with Domain 7 (fears) being the exception. Internal consistency was good (α = 0.866). Convergent (using Short-Form 36-Item and EQ-5D) and divergent construct validity (using EQ-5D) was confirmed. Test-retest reliability was excellent [intraclass correlation coefficient = 0.918 (0.834-0.961)], with a standard error of measurement of 3.88 and a smallest detectable change of 10.76 points. We found moderate responsiveness when five of the nine hypotheses were confirmed, coupled with a large effect size for the overall SarQoL score (corrected standardized response mean of -1.44). CONCLUSIONS: The SarQoL questionnaire has adequate clinimetric properties for use with frail patients in clinical practice and trials and could provide data that are more appropriate and detailed than the generic questionnaires currently used