Testicular Microanatomy of Rhabdophis tigrinus During theBreeding and Nonbreeding Seasons

Rhabdophis tigrinus, the Tiger Keelback, is native to East and Southeast Asia. It preys on amphibians, including the Japanese toad, Bufo japonicus. It secretes cardiotonic steroids known as bufadienolides (BDs) from its skin. Consumption of BDs is typically fatal in other snake species, but, R. tigrinus displays resistance to these toxins. After consuming toads, R. tigrinus sequesters BDs into glands on its neck. The adrenal glands of R. tigrinus are enlarged in comparison to similar species

CyCLIP: Cyclic Contrastive Language-Image Pretraining

Recent advances in contrastive representation learning over paired image-text data have led to models such as CLIP that achieve state-of-the-art performance for zero-shot classification and distributional robustness. Such models typically require joint reasoning in the image and text representation spaces for downstream inference tasks. Contrary to prior beliefs, we demonstrate that the image and text representations learned via a standard contrastive objective are not interchangeable and can lead to inconsistent downstream predictions. To mitigate this issue, we formalize consistency and propose CyCLIP, a framework for contrastive representation learning that explicitly optimizes for the learned representations to be geometrically consistent in the image and text space. In particular, we show that consistent representations can be learned by explicitly symmetrizing (a) the similarity between the two mismatched image-text pairs (cross-modal consistency); and (b) the similarity between the image-image pair and the text-text pair (in-modal consistency). Empirically, we show that the improved consistency in CyCLIP translates to significant gains over CLIP, with gains ranging from 10%-24% for zero-shot classification accuracy on standard benchmarks (CIFAR-10, CIFAR-100, ImageNet1K) and 10%-27% for robustness to various natural distribution shifts. The code is available at https://github.com/goel-shashank/CyCLIP.Comment: 19 pages, 13 tables, 6 figures, Oral at NeuRIPS 202

Asexuality is Inversely Associated with Positive Body Image in British Adults

Research on positive body image has infrequently considered sexual minority orientations beyond lesbians, gay men, and bisexual persons. Indeed, there is no existing research on the relationships between body image and asexuality, which refers to a lack of sexual attraction to anyone or anything. In two studies, we rectified this by examining associations between asexuality – operationalised as a continuous construct – and indices of positive body image. In Study 1, 188 Britons from the community completed measures of asexuality and body appreciation. Once the effects of self-identified sexual orientation, relationship status, and body mass index (BMI) had been considered, asexuality was found to be significantly and negatively associated with body appreciation in women and men. In Study 2, an online sample of 377 Britons completed measures of asexuality, body appreciation, functionality appreciation, body acceptance from others, and body image flexibility. Beyond the effects of sexual orientation, relationship status, and BMI, asexuality was significantly and negatively associated with all four body image constructs in men, and with body appreciation and functionality appreciation in women. Although asexuality only explained a small proportion of the variance in positive body image (3-11%) and further studies are needed, the relationship appears to be stable

Land use change alters carbon composition and degree of decomposition of tropical peat soils

Drainage associated with land use change in tropical peatlands has increased the rate of decomposition of peat soils and contributed to CO2 emissions. Increased decomposition may result in changes in the composition of the soil organic carbon (SOC). We examined the carbon functional group composition and degree of decomposition of peat soils under five different land uses to understand the effects of changing management intensity on tropical peatland soils. Samples were collected from seven sites spanning five different land uses (forest, shrubland, fernland, revegetation, smallholder oil palm) at the Pedamaran peatland in South Sumatra, Indonesia. SOC composition, measured by Solid-state 13C Nuclear Magnetic Resonance (NMR) spectroscopy, was dominated by the alkyl carbon (C) functional group in managed peatlands. However, in the forest far from drainage canals, the SOC comprised predominantly O-alkyl C. The contributions of the functional groups ketone C, carbonyl C and O-aryl C were low and tended to occur in stable proportions throughout the soil profiles. Drainage and land use change significantly affected peat carbon chemistry. The effects were greatest under oil palm, where O-alkyl C had been depleted rapidly under aerobic conditions leading to a change in the dominant carbon functional group from O-alkyl C to alkyl C. Furthermore, our results indicate that the alkyl C:O-alkyl C ratio is a more useful and informative indicator of the degree of decomposition of peat soil than the traditionally used C:N ratio. This more nuanced understanding of the different types of carbon that make up tropical peat soils under different land uses can be applied to support peatland restoration. In particular, nutrient cycling and water availability are likely to be influenced by carbon functional group and degree of decomposition. In order to reduce fire risk and support Indonesia’s aspirations to manage the national forest estate as a net carbon sink, further research into the links between peat soil organic carbon chemistry, revegetation performance and new peat accumulation is recommended

PTCOG Head and Neck Subcommittee Consensus Guidelines on Particle Therapy for the Management of Head and Neck Tumors

Purpose: Radiation therapy is a standard modality in the treatment for cancers of the head and neck, but is associated with significant short- and long-term side effects. Proton therapy, with its unique physical characteristics, can deliver less dose to normal tissues, resulting in fewer side effects. Proton therapy is currently being used for the treatment of head and neck cancer, with increasing clinical evidence supporting its use. However, barriers to wider adoption include access, cost, and the need for higher-level evidence.Methods: The clinical evidence for the use of proton therapy in the treatment of head and neck cancer are reviewed here, including indications, advantages, and challenges.Results: The Particle Therapy Cooperative Group Head and Neck Subcommittee task group provides consensus guidelines for the use of proton therapy for head and neck cancer.Conclusion: This report can be used as a guide for clinical use, to understand clinical trials, and to inform future research efforts.</p

Glutamate is required for depression but not potentiation of long-term presynaptic function

Hebbian plasticity is thought to require glutamate signalling. We show this is not the case for hippocampal presynaptic long-term potentiation (LTPpre), which is expressed as an increase in transmitter release probability (Pr). We find that LTPpreandnbsp;can be induced by pairing pre- and postsynaptic spiking in the absence of glutamate signalling. LTPpreinduction involves a non-canonical mechanism of retrograde nitric oxide signalling, which is triggered by Ca2+andnbsp;influx from L-type voltage-gated Ca2+andnbsp;channels, not postsynaptic NMDA receptors (NMDARs), and does not require glutamate release. When glutamate release occurs, it decreases Prandnbsp;by activating presynaptic NMDARs, and promotes presynaptic long-term depression. Net changes in Pr, therefore, depend on two opposing factors: (1) Hebbian activity, which increases Pr, and (2) glutamate release, which decreases Pr. Accordingly, release failures during Hebbian activity promote LTPpreinduction. Our findings reveal a novel framework of presynaptic plasticity that radically differs from traditional models of postsynaptic plasticity.</p

Impact of Screencast Technology: Connecting the Perception of Usefulness and the Reality of Performance

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/95369/1/j.2168-9830.2012.tb01126.x.pd

C/EBP alpha and GATA-2 Mutations Induce Bilineage Acute Erythroid Leukemia through Transformation of a Neomorphic Neutrophil-Erythroid Progenitor

Acute erythroid leukemia (AEL) commonly involves both myeloid and erythroid lineage transformation. However, the mutations that cause AEL and the cell(s) that sustain the bilineage leukemia phenotype remain unknown. We here show that combined biallelic Cebpa and Gata2 zinc finger-1 (ZnF1) mutations cooperatively induce bilineage AEL, and that the major leukemia-initiating cell (LIC) population has a neutrophil-monocyte progenitor (NMP) phenotype. In pre-leukemic NMPs Cebpa and Gata2 mutations synergize by increasing erythroid transcription factor (TF) expression and erythroid TF chromatin access, respectively, thereby installing ectopic erythroid potential. This erythroid-permissive chromatin conformation is retained in bilineage LICs. These results demonstrate that synergistic transcriptional and epigenetic reprogramming by leukemia-initiating mutations can generate neomorphic pre-leukemic progenitors, defining the lineage identity of the resulting leukemia

Scaling of columnar joints in basalt

We describe field work, analysis, and modeling of columnar joints from the Columbia River Basalt Group. This work is focused on the regions around the Grand Coulee, Snake River, and Columbia Gorge, which form parts of this unusually homogeneous and very large sample of columnar basalt. We examine in detail the scaling relationship between the column width and the size of the striae and relate these quantitatively to thermal and fracture models. We found that the column radius and stria size are proportional to each other and inversely proportional to the cooling rate of the lava. Near a flow margin, our results put observational constraints on diffusive thermal models of joint formation. Deeper than a few meters into a colonnade, our measurements are consistent with a simple advection-diffusion model of two-phase convective cooling within the joints, regardless of the direction of cooling. This model allows an accurate comparison of igneous columnar jointing and joints due to desiccation in laboratory analog systems. We also identify a new length scale in which wavy columns can appear in some colonnades. The mechanisms leading to the wavy columns are likely related to those underlying similar wavy cracks in 2-D analog systems