The physiology of flowering in Pisum sativum (the garden pea)

Late varieties of the garden pea are quantitatively long day photo-periodically sensitive and can be vernalised (Barberm, 1959). This was verified and the increased response to day length and vernalisation in the tall late variety Telephone over the dwarf late variety Greenfeast was noted. Late varieties of garden pea grown in the field flowered at a lower average node than was found with any of the plants grown in growth environmental chambers and attempts were made to simulate under controlled conditions the variations between plants grown in the field and plants grown in growth cabinets. Lowering the intensity of light incident on plants reduces plant height and dry weight but does not affect flowering. High intensity blue light and various ratios of red to far red supplementary light were tested but these did not affect plant growth or flowering. Different growth media (soil, peralite with nutrient solution) and the presence or absence of root nodules were tested and found to have no effect on growth or flowering. The effect of gibberellic acid on growth and flowering were studied and it was shown that a natural dwarf late variety given the phenotype of a tall variety by applications of gibberellic acid would respond to day-length and vernalisation in a similar manner to a natural tall late variety. A general delay in flowering and fruit set in both natural tall and natural dwarf varieties was noted after applications of gibberellic acid and this was noted to be more pronounced under short day growth conditions. The effects of the removal of cotyledons on growth, development and flowering of garden pea plants was studied and it was shown that after removal of the cotyledons plant growth rate was reduced, internodes were shorter, leaflets were smaller and plants flowered earlier than control plants which had retained their cotyledons. It was also shown that the reduced vegetative growth rate continued throughout the entire life of the plant provided that the cotyledons were removed before 240 hours after planting, and that plants without cotyledons flowered at a lower average node than controls provided that the cotyledons were removed within 120 hours of planting. Various compounds (gibberellic acid, sucrose, kinetin, indolyl acetic acid and pea cotyledon extracts) were applied to decotylised plants in attempts to restore vegetative vigour and normal flowering pattern. All compounds failed completely to restore the vegetative vigour and normal flowering pattern of the controls. Parts of the cotyledon complement were removed and the effects on growth and flowering were recorded. One quarter of the cotyledon complement was shown to be adequate to allow plants to flower normally and one complete cotyledon was sufficient to allow for normal growth. It was shown that decotylised plants could be vernalised and that the cotyledons are not the site of perception of the cold stimulus of a period of vernalisation

Assessing the efficacy of medetomidine and tiletamine-zolazepam for remote immobilisation of feral horses (Equus caballus)

Context The study of any wild animal's home range requires the collection of spatiotemporal data, obtained independently of climatic conditions or time of day. This can be achieved by the attachment of global positioning system (GPS) data loggers, which, in large species, is best achieved by remote immobilisation. Feral horses (Equus caballus) usually occupy remote areas of Australia; however, a considerable population increase has been observed in a close proximity to metropolitan areas of the Australian east coast, creating increasing conflict with human interests. Aim The aim of the present study was to investigate the efficacy of remote chemical immobilisation of feral horses with medetomidine combined with tiletamine-zolazepam to facilitate placement of satellite GPS collars. Methods Nine feral horses were darted from the ground with 60mg (i.m.) medetomidine and 1500mg (i.m.) tiletamine-zolazepam. The effects of medetomidine were reversed with 50-100mg (i.m. or i.v.) atipamezole 30-40min after induction (IV/IM). Physiological variables monitored during anaesthesia were heart rate, respiratory rate, temperature and oxygen haemoglobin saturation (Spo2). Key results All horses were successfully immobilised with between one and three darts (n≤9). The mean (± s.e.m.) dose of medetomidine was 0.15±0.01mg kg-1, whereas that of tiletamine-zolazepam was 3.61±0.16mg kg-1. Mean time from darting to lateral recumbency was 13.3±2.7min and mean recumbency time was 54±13min. Vital signs for all anaesthetised animals remained within the normal range during anaesthesia, with the exception of one animal exhibiting a transient drop in Spo2. There were no deaths. Key conclusions The combination of medetomidine and tiletamine-zolazepam provided adequate anaesthesia in feral horses in the field for application of GPS collars. Implications Although a limited number of horses was immobilised, the present study shows that the combination of medetomidine and tiletamine-zolazepam provides effective short-term anaesthesia for feral horses, affording a practical and field-accessible capture technique. This method could also be applied to other management actions requiring the safe and humane capture of feral horses

Race/Ethnicity and Geographic Access to Urban Trauma Care

Importance Little is known about the distribution of life-saving trauma resources by racial/ethnic composition in US cities, and if racial/ethnic minority populations disproportionately live in US urban trauma deserts. Objective To examine racial/ethnic differences in geographic access to trauma care in the 3 largest US cities, considering the role of residential segregation and neighborhood poverty. Design, Setting, and Participants A cross-sectional, multiple-methods study evaluated census tract data from the 2015 American Community Survey in Chicago, Illinois; Los Angeles (LA), California; and New York City (NYC), New York (N = 3932). These data were paired to geographic coordinates of all adult level I and II trauma centers within an 8.0-km buffer of each city. Between February and September 2018, small-area analyses were conducted to assess trauma desert status as a function of neighborhood racial/ethnic composition, and geospatial analyses were conducted to examine statistically significant trauma desert hot spots. Main Outcomes and Measures In small-area analyses, a trauma desert was defined as travel distance greater than 8.0 km to the nearest adult level I or level II trauma center. In geospatial analyses, relative trauma deserts were identified using travel distance as a continuous measure. Census tracts were classified into (1) racial/ethnic composition categories, based on patterns of residential segregation, including white majority, black majority, Hispanic/Latino majority, and other or integrated; and (2) poverty categories, including nonpoor and poor. Results Chicago, LA, and NYC contained 798, 1006, and 2128 census tracts, respectively. A large proportion comprised a black majority population in Chicago (35.1%) and NYC (21.4%), compared with LA (2.7%). In primary analyses, black majority census tracts were more likely than white majority census tracts to be located in a trauma desert in Chicago (odds ratio [OR], 8.48; 95% CI, 5.71-12.59) and LA (OR, 5.11; 95% CI, 1.50-17.39). In NYC, racial/ethnic disparities were not significant in unadjusted models, but were significant in models adjusting for poverty and race-poverty interaction effects (adjusted OR, 1.87; 95% CI, 1.27-2.74). In comparison, Hispanic/Latino majority census tracts were less likely to be located in a trauma desert in NYC (OR, 0.03; 95% CI, 0.01-0.11) and LA (OR, 0.30; 95% CI, 0.22-0.40), but slightly more likely in Chicago (OR, 2.38; 95% CI, 1.56-3.64). Conclusions and Relevance In this study, black majority census tracts were the only racial/ethnic group that appeared to be associated with disparities in geographic access to trauma centers

Assessment of antibiotic de-escalation by spectrum score in patients with nosocomial pneumonia: A single-center, retrospective cohort study

Background: Hospital-acquired and ventilator-associated pneumonia (HAP/VAP) cause significant mortality. Guidelines recommend empiric broad-spectrum antibiotics followed by de-escalation (DE). This study sought to assess the impact of DE on treatment failure. Methods: This single-center retrospective cohort study screened all adult patients with a discharge diagnosis code for pneumonia from 2016 to 2019. Patients were enrolled if they met predefined criteria for HAP/VAP ≥48 hours after admission. Date of pneumonia diagnosis was defined as day 0. Spectrum scores were calculated, and DE was defined as a score reduction on day 3 versus day 1. Patients with DE were compared to patients with no de-escalation (NDE). The primary outcome was composite treatment failure, defined as all-cause mortality or readmission for pneumonia within 30 days of diagnosis. Results: Of 11860 admissions screened, 1812 unique patient-admissions were included (1102 HAP, 710 VAP). Fewer patients received DE (876 DE vs 1026 NDE). Groups were well matched at baseline, although more patients receiving DE had respiratory cultures ordered (56.6% vs 50.6%, Conclusions: De-escalation and NDE resulted in similar rates of 30-day treatment failure; however, DE was associated with fewer antibiotic days, episodes o

Preliminary Results on HAT-P-4, TrES-3, XO-2, and GJ 436 from the NASA EPOXI Mission

EPOXI (EPOCh + DIXI) is a NASA Discovery Program Mission of Opportunity using the Deep Impact flyby spacecraft. The EPOCh (Extrasolar Planet Observation and Characterization) Science Investigation will gather photometric time series of known transiting exoplanet systems from January through August 2008. Here we describe the steps in the photometric extraction of the time series and present preliminary results of the first four EPOCh targets.Comment: 4 pages, 2 figures. To appear in the Proceedings of the 253rd IAU Symposium: "Transiting Planets", May 2008, Cambridge, M

iPSC-derived myelinoids to study myelin biology of humans

Myelination is essential for central nervous system (CNS) formation, health, and function. Emerging evidence of oligodendrocyte heterogeneity in health and disease and divergent CNS gene expression profiles between mice and humans supports the development of experimentally tractable human myelination systems. Here, we developed human iPSC-derived myelinating organoids (“myelinoids”) and quantitative tools to study myelination from oligodendrogenesis through to compact myelin formation and myelinated axon organization. Using patient-derived cells, we modeled a monogenetic disease of myelinated axons (Nfasc155 deficiency), recapitulating impaired paranodal axo-glial junction formation. We also validated the use of myelinoids for pharmacological assessment of myelination—both at the level of individual oligodendrocytes and globally across whole myelinoids—and demonstrated reduced myelination in response to suppressed synaptic vesicle release. Our study provides a platform to investigate human myelin development, disease, and adaptive myelination