Understorey light quality affects leaf pigments and leaf phenology in different plant functional types

Forest understorey plants receive most sunlight in springtime before canopy closure, and in autumn following leaf-fall. We hypothesized that plant species must adjust their phenological and photoprotective strategies in response to large changes in the spectral composition of the sunlight they receive. Here, we identified how plant species growing in northern deciduous and evergreen forest understoreys differ in their response to blue light and ultraviolet (UV) radiation according to their functional strategy. We installed filters in a forest understorey in southern Finland, to create the following treatments attenuating: UV radiation < 350 nm, all UV radiation (< 400 nm), all blue light and UV radiation (< 500 nm), and a transparent control. In eight species, representing different functional strategies, we assessed leaf optical properties, phenology, and epidermal flavonoid contents over two years. Blue light accelerated leaf senescence in all species measured in the understorey, apart from Quercus robur seedlings, whereas UV radiation only accelerated leaf senescence in Acer platanoides seedlings. More light-demanding species accumulated flavonols in response to seasonal changes in light quality compared to shade-tolerant and wintergreen species and were particularly responsive to blue light. Reduction of blue and UV radiation under shade reveals an important role for microclimatic effects on autumn phenology and leaf photoprotection. An extension of canopy cover under climate change, and its associated suppression of understorey blue light and UV radiation, may delay leaf senescence for understorey species with an autumn niche.Peer reviewe

A DR4:tBID axis drives the p53 apoptotic response by promoting oligomerization of poised BAX

The cellular response to p53 activation varies greatly in a stimulus‐ and cell type‐specific manner. Dissecting the molecular mechanisms defining these cell fate choices will assist the development of effective p53‐based cancer therapies and also illuminate fundamental processes by which gene networks control cellular behaviour. Using an experimental system wherein stimulus‐specific p53 responses are elicited by non‐genotoxic versus genotoxic agents, we discovered a novel mechanism that determines whether cells undergo proliferation arrest or cell death. Strikingly, we observe that key mediators of cell‐cycle arrest (p21, 14‐3‐3σ) and apoptosis (PUMA, BAX) are equally activated regardless of outcome. In fact, arresting cells display strong translocation of PUMA and BAX to the mitochondria, yet fail to release cytochrome C or activate caspases. Surprisingly, the key differential events in apoptotic cells are p53‐dependent activation of the DR4 death receptor pathway, caspase 8‐mediated cleavage of BID, and BID‐dependent activation of poised BAX at the mitochondria. These results reveal a previously unappreciated role for DR4 and the extrinsic apoptotic pathway in cell fate choice following p53 activation.Fil: Henry, Ryan E. State University Of Colorado-boulder; Estados UnidosFil: Andrysik, Zdenek. State University Of Colorado-boulder; Estados UnidosFil: Paris, Ramiro. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Mar del Plata. Instituto de Investigaciones Biológicas; Argentina. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Biológicas; Argentina. State University Of Colorado-boulder; Estados UnidosFil: Galbraith, Matthew D.. State University Of Colorado-boulder; Estados UnidosFil: Espinosa, Joaquín M.. State University Of Colorado-boulder; Estados Unido

Reducing Cycle Time in Frozen Gel-Bag Production

PurFoods estimates they will use two million gel-bags this year in their packaged meal delivery boxes. Currently, cycle time to freeze gel-bags is about 24 hours. PurFoods would like to reduce this time by at least 25%, opening up valuable inventory space and providing flexibility in meeting market demands

SKPs Derive from Hair Follicle Precursors and Exhibit Properties of Adult Dermal Stem Cells

SummaryDespite the remarkable regenerative capacity of mammalian skin, an adult dermal stem cell has not yet been identified. Here, we investigated whether skin-derived precursors (SKPs) might fulfill such a role. We show that SKPs derive from Sox2+ hair follicle dermal cells and that these two cell populations are similar with regard to their transcriptome and functional properties. Both clonal SKPs and endogenous Sox2+ cells induce hair morphogenesis, differentiate into dermal cell types, and home to a hair follicle niche upon transplantation. Moreover, hair follicle-derived SKPs self-renew, maintain their multipotency, and serially reconstitute hair follicles. Finally, grafting experiments show that follicle-associated dermal cells move out of their niche to contribute cells for dermal maintenance and wound-healing. Thus, SKPs derive from Sox2+ follicle-associated dermal precursors and display functional properties predicted of a dermal stem cell, contributing to dermal maintenance, wound-healing, and hair follicle morphogenesis

Probing the Circumgalactic Medium at High-Redshift Using Composite BOSS Spectra of Strong Lyman-alpha Forest Absorbers

We present composite spectra constructed from a sample of 242,150 Lyman-alpha (Lya) forest absorbers at redshifts 2.4<z<3.1 identified in quasar spectra from the Baryon Oscillation Spectroscopic Survey (BOSS) as part of Data Release 9 of the Sloan Digital Sky Survey III. We select forest absorbers by their flux in bins 138 km/s wide (approximately the size of the BOSS resolution element). We split these absorbers into five samples spanning the range of flux -0.05 < F<0.45. Tests on a smaller sample of high-resolution spectra show that our three strongest absorption bins would probe circumgalactic regions (projected separation < 300 proper kpc and |Delta v| < 300km/s) in about 60% of cases for very high signal-to-noise ratio. Within this subset, weakening Lya absorption is associated with decreasing purity of circumgalactic selection once BOSS noise is included. Our weaker two Lya absorption samples are dominated by the intergalactic medium. We present composite spectra of these samples and a catalogue of measured absorption features from HI and 13 metal ionization species, all of which we make available to the community. We compare measurements of seven Lyman series transitions in our composite spectra to single line models and obtain further constraints from their associated excess Lyman limit opacity. This analysis provides results consistent with column densities over the range 14.4 <~ Log (N_HI) <~ 16.45. We compare our measurements of metal absorption to a variety of simple single-line, single-phase models for a preliminary interpretation. Our results imply clumping on scales down to ~30 pc and near-solar metallicities in the circumgalactic samples, while high-ionization metal absorption consistent with typical IGM densities and metallicities is visible in all samples.Comment: 23 pages, 15 figures, 5 tables, link to downloadable data included. Accepted by MNRAS 2014 March 20. New sections 3.4 and 6.1 limiting the occurrence and impact of Lyman limit system

The prevalence and clinical associations of mood instability in adults living in England : results from the Adult Psychiatric Morbidity Survey 2007

Mood instability is underinvestigated but potentially clinically important. This study aimed to describe the prevalence of mood instability in adults living in England and test whether it is important in explaining the extent of symptoms of common mental disorders, suicidality and healthcare use. An analysis of data from the Adult Psychiatric Morbidity Survey 2007, a household survey of private households in England (N=7403), was completed. The prevalence of mood instability was 13.9%. In univariate analysis it was strongly associated with socio-demographic and clinical variables. In regression modelling mood instability was independently associated with non-psychotic psychopathology, increasing the odds by 9.89. It was also linked with suicidal ideas (odds ratios (OR): 2.04) but not suicidal acts, and associated with being in receipt of medication, counselling or therapy for mental health problems (OR: 1.88), independent of a diagnosis of borderline personality disorder. Mood instability is relatively common in the adult population, occurs frequently in common mental disorders and appears to be an important symptom in its own right. It is associated with two important measures in psychiatry, namely suicidal thinking and healthcare service use. It warrants more widespread recognition and further research is required to understand if, when and how to intervene

Early quick acuity score provides more complete data on emergency department walkouts.

INTRODUCTION: Many prior studies have compared the acuity of Emergency Department (ED) patients who have Left Without Being Seen (LWBS) against non-LWBS patients. A weakness in these studies is that patients may walk out prior to the assignment of a triage score, biasing comparisons. We report an operational change whereby acuity was assessed immediately upon patient arrival. We hypothesized more patients would receive acuity scores with EQAS. We also sought to compare LWBS and non-LWBS patient characteristics with reduced bias. SETTING: urban, academic medical center. Retrospective cohort study, electronic chart review, collecting data on all ED patients presenting between 4/1/2010 and 10/31/2011 ( Traditional Acuity Score period, TAS) and from 11/1/2011 to 3/31/2012 ( Early Quick Acuity Score period, EQAS). We recorded disposition (LWBS versus non-LWBS), acuity and demographics. For each subject during the EQAS period, we calculated how many prior ED visits and how many prior walkouts the subject had had during the TAS period. RESULTS: Acuity was recorded in 92,275 of 94,526 patients (97.6%) for TAS period, and 25,577 of 25,760 patients (99.3%) for EQAS period, a difference of 1.7% (1.5%, 1.8%). LWBS patients had acuity scores recorded in 5,180 of 7,040 cases (73.6%) during TAS period, compared with 897 of 1,010 cases (88.8%) during the EQAS period, a difference of 15.2% (14.8%, 15.7%). LWBS were more likely than non-LWBS to be male, were younger and had lower acuity scores. LWBS averaged 5.3 prior ED visits compared with 2.8 by non-LWBS, a difference of 2.5 (1.5, 3.5). LWBS averaged 1.3 prior ED walkouts compared with 0.2 among non-LWBS, a difference of 1.1 (0.8, 1.3). CONCLUSIONS: EQAS resulted in a higher proportion of patients receiving acuity scores, particularly among LWBS. This offers more complete data when comparing LWBS and non-LWBS patient characteristics. The comparison reinforced findings from prior studies

Silencing porcine CMAH and GGTA1 genes significantly reduces xenogeneic consumption of human platelets by porcine livers

BACKGROUND: A profound thrombocytopenia limits hepatic xenotransplantation in the pig-to-primate model. Porcine livers also have shown the ability to phagocytose human platelets in the absence of immune-mediated injury. Recently, inactivation of the porcine ASGR1 gene has been shown to decrease this phenomenon. Inactivating GGTA1 and CMAH genes has reduced the antibody-mediated barrier to xenotransplantation; herein, we describe the effect that these modifications have on xenogeneic consumption of human platelets in the absence of immune-mediated graft injury. METHODS: Wild type (WT), ASGR1, GGTA1, and GGTA1CMAH knockout pigs were compared for their xenogeneic hepatic consumption of human platelets. An in vitro assay was established to measure the association of human platelets with liver sinusoidal endothelial cells (LSECs) by immunohistochemistry. Perfusion models were used to measure human platelet uptake in livers from WT, ASGR1, GGTA1, and GGTA1 CMAH pigs. RESULTS: GGTA1, CMAH LSECs exhibited reduced levels of human platelet binding in vitro when compared with GGTA1 and WT LSECs. In a continuous perfusion model, GGTA1 CMAH livers consumed fewer human platelets than GGTA1 and WT livers. GGTA1 CMAH livers also consumed fewer human platelets than ASGR1 livers in a single-pass model. CONCLUSIONS: Silencing the porcine carbohydrate genes necessary to avoid antibody-mediated rejection in a pig-to-human model also reduces the xenogeneic consumption of human platelets by the porcine liver. The combination of these genetic modifications may be an effective strategy to limit the thrombocytopenia associated with pig-to-human hepatic xenotransplantation

An integrative investigation of sensory organ development and orientation behavior throughout the larval phase of a coral reef fish

The dispersal of marine larvae determines the level of connectivity among populations, influences population dynamics, and affects evolutionary processes. Patterns of dispersal are influenced by both ocean currents and larval behavior, yet the role of behavior remains poorly understood. Here we report the first integrated study of the ontogeny of multiple sensory systems and orientation behavior throughout the larval phase of a coral reef fish—the neon goby, Elacatinus lori. We document the developmental morphology of all major sensory organs (lateral line, visual, auditory, olfactory, gustatory) together with the development of larval swimming and orientation behaviors observed in a circular arena set adrift at sea. We show that all sensory organs are present at hatch and increase in size (or number) and complexity throughout the larval phase. Further, we demonstrate that most larvae can orient as early as 2 days post-hatch, and they swim faster and straighter as they develop. We conclude that sensory organs and swimming abilities are sufficiently developed to allow E. lori larvae to orient soon after hatch, suggesting that early orientation behavior may be common among coral reef fishes. Finally, we provide a framework for testing alternative hypotheses for the orientation strategies used by fish larvae, laying a foundation for a deeper understanding of the role of behavior in shaping dispersal patterns in the sea