An Improved Holding Chamber for the Measurement of Oxygen Consumption in Mice

An apparatus is described which has been useful in classroom demonstrations and for research in metabolic studies of mice. The unique feature of this modification of basic metabolators is a standard taper ground glass joint

A Global Perspective on Phosphorus Management Decision Support in Agriculture: Lessons Learned and Future Directions

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Mapping forest cover and forest cover change with airborne S-band radar

Assessments of forest cover, forest carbon stocks and carbon emissions from deforestation and degradation are increasingly important components of sustainable resource management, for combating biodiversity loss and in climate mitigation policies. Satellite remote sensing provides the only means for mapping global forest cover regularly. However, forest classification with optical data is limited by its insensitivity to three-dimensional canopy structure and cloud cover obscuring many forest regions. Synthetic Aperture Radar (SAR) sensors are increasingly being used to mitigate these problems, mainly in the L-, C- and X-band domains of the electromagnetic spectrum. S-band has not been systematically studied for this purpose. In anticipation of the British built NovaSAR-S satellite mission, this study evaluates the benefits of polarimetric S-band SAR for forest characterisation. The Michigan Microwave Canopy Scattering (MIMICS-I) radiative transfer model is utilised to understand the scattering mechanisms in forest canopies at S-band. The MIMICS-I model reveals strong S-band backscatter sensitivity to the forest canopy in comparison to soil characteristics across all polarisations and incidence angles. Airborne S-band SAR imagery over the temperate mixed forest of Savernake Forest in southern England is analysed for its information content. Based on the modelling results, S-band HH- and VV-polarisation radar backscatter and the Radar Forest Degradation Index (RFDI) are used in a forest/non-forest Maximum Likelihood classification at a spatial resolution of 6 m (70% overall accuracy, κ = 0.41) and 20 m (63% overall accuracy, κ = 0.27). The conclusion is that S-band SAR such as from NovaSAR-S is likely to be suitable for monitoring forest cover and its change

An extended set of PRDM1/BLIMP1 target genes links binding motif type to dynamic repression

The transcriptional repressor B lymphocyte-induced maturation protein-1 (BLIMP1) regulates gene expression and cell fate. The DNA motif bound by BLIMP1 in vitro overlaps with that of interferon regulatory factors (IRFs), which respond to inflammatory/immune signals. At such sites, BLIMP1 and IRFs can antagonistically regulate promoter activity. In vitro motif selection predicts that only a subset of BLIMP1 or IRF sites is subject to antagonistic regulation, but the extent to which antagonism occurs is unknown, since an unbiased assessment of BLIMP1 occupancy in vivo is lacking. To address this, we identified an extended set of promoters occupied by BLIMP1. Motif discovery and enrichment analysis demonstrate that multiple motif variants are required to capture BLIMP1 binding specificity. These are differentially associated with CpG content, leading to the observation that BLIMP1 DNA-binding is methylation sensitive. In occupied promoters, only a subset of BLIMP1 motifs overlap with IRF motifs. Conversely, a distinct subset of IRF motifs is not enriched amongst occupied promoters. Genes linked to occupied promoters containing overlapping BLIMP1/IRF motifs (e.g. AIM2, SP110, BTN3A3) are shown to constitute a dynamic target set which is preferentially activated by BLIMP1 knock-down. These data confirm and extend the competitive model of BLIMP1 and IRF interaction

The Motheaten Mutation Rescues B Cell Signaling and Development in CD45-deficient Mice

The cytosolic SHP-1 and transmembrane CD45 protein tyrosine phosphatases (PTP) play critical roles in regulating signal transduction via the B cell antigen receptor (BCR). These PTPs differ, however, in their effects on BCR function. For example, BCR-mediated mitogenesis is essentially ablated in mice lacking CD45 (CD45−), but is enhanced in SHP-1–deficient motheaten (me) and viable motheaten (mev) mice. To determine whether these PTPs act independently or coordinately in modulating the physiologic outcome of BCR engagement, we assessed B cell development and signaling in CD45-deficient mev (CD45−/SHP-1−) mice. Here we report that the CD45−/SHP-1− cells undergo appropriate induction of protein kinase activity, mitogen-activated protein kinase activation, and proliferative responses after BCR aggregation. However, BCR-elicited increases in the tyrosine phosphorylation of several SHP-1–associated phosphoproteins, including CD19, were substantially enhanced in CD45−/SHP-1−, compared to wild-type and CD45− cells. In addition, we observed that the patterns of cell surface expression of μ, δ, and CD5, which distinguish the PTP-deficient from normal mice, are largely restored to normal levels in the double mutant animals. These findings indicate a critical role for the balance of SHP-1 and CD45 activities in determining the outcome of BCR stimulation and suggest that these PTPs act in a coordinate fashion to couple antigen receptor engagement to B cell activation and maturation

Recovery and resilience of urban stream metabolism following Superstorm Sandy and other floods

Urban streams are exposed to multiple different stressors on a regular basis, with increased hydrological flashiness representing a common urban stream stressor. Stream metabolism, the coupled ecosystem functions of gross primary production (GPP) and ecosystem respiration (ER), controls numerous other ecosystem functions and integrates multiple processes occurring within streams. We examined the effect of one large (Superstorm Sandy) and multiple small and moderately sized flood events in Baltimore, Maryland, to quantify the response and recovery of urban stream GPP and ER before and after floods of different magnitudes. We also compared GPP and ER before and after Superstorm Sandy to literature values. We found that both GPP and ER decreased dramatically immediately following floods of varying magnitudes, but on average GPP was more reduced than ER (80% and 66% average reduction in GPP and ER, respectively). Both GPP and ER recovered rapidly following floods within 4–18 d, and recovery intervals did not differ significantly between GPP and ER. During the two-week recovery following Superstorm Sandy, two urban streams exhibited a range of metabolic activity equivalent to ~15% of the entire range of GPP and ER reported in a recent meta-analysis of stream metabolism. Urban streams exhibit a substantial proportion of the natural variation in metabolism found across stream ecosystems over relatively short time scales. Not only does urbanization cause increased hydrological flashiness, it appears that metabolic activity in urban streams may be less resistant, but also more resilient to floods than in other streams draining undeveloped watersheds, which have been more studied. Our results show that antecedent conditions must be accounted for when drawing conclusions about stream metabolism measurements, and the rapid recovery and resilience of urban streams should be considered in watershed management and stream restoration strategies targeting ecosystem functions and services

Systematic review investigating the reporting of comorbidities and medication in randomized controlled trials of people with dementia

Objectives: dementia is a debilitating condition characterised by global loss of cognitive and intellectual functioning, which reduces social and occupational performance. This population frequently presents with medical co-morbidities such as hypertension, cardiovascular disease and diabetes. The CONSORT statement outlines recommended guidance on reporting of participant characteristics in clinical trials. It is, however, unclear how much these are adhered to in trials assessing people with dementia. This paper assesses the reporting of medical co-morbidities and prescribed medications for people with dementia within randomised controlled trial (RCT) reports. Design: a systematic review of the published literature from the databases AMED, CINAHL, MEDLINE, EMBASE and the Cochrane Clinical Trial Registry from 1 January 1997 to 9 January 2014 was undertaken in order to identify RCTs detailing baseline medical co-morbidities and prescribed medications . Eligible studies were appraised using the Critical Appraisal Skills Programme (CASP) RCT appraisal tool, and descriptive statistical analyses were calculated to determine point prevalence. Results: nine trials, including 1474 people with dementia, were identified presenting medical co-morbidity data. These indicated neurological disorders ( prevalence 91%), vascular disorders (prevalence 91%), cardiac disorders ( prevalence 74%) and ischaemic cerebrovascular disease ( prevalence 53%) were most frequently seen. Conclusions: published RCTs poorly report medical co-morbidities and medications for people with dementia. Future trials should include the report of these items to allow interpretation of whether the results are generalisable to frailer older populations