The nature of science: The fundamental role of natural history in ecology, evolution, conservation, and education.

There is a contemporary trend in many major research institutions to de-emphasize the importance of natural history education in favor of theoretical, laboratory, or simulation-based research programs. This may take the form of removing biodiversity and field courses from the curriculum and the sometimes subtle maligning of natural history research as a "lesser" branch of science. Additional threats include massive funding cuts to natural history museums and the maintenance of their collections, the extirpation of taxonomists across disciplines, and a critical under-appreciation of the role that natural history data (and other forms of observational data, including Indigenous knowledge) play in the scientific process.

Dermatologic Implications of Sleep Deprivation in the US Military.

Short sleep duration is common among US adults and is even more common among people working in protective services and the military. Military service predisposes members to disordered sleep due to the rigors of deployments and field training. In this article, we explore possible mechanisms by which sleep deprivation may affect the skin.

Histone H3K9 methylation promotes formation of genome compartments in via chromosome compaction and perinuclear anchoring.

Genomic regions preferentially associate with regions of similar transcriptional activity, partitioning genomes into active and inactive compartments within the nucleus. Here we explore mechanisms controlling genome compartment organization in and investigate roles for compartments in regulating gene expression. Distal arms of chromosomes, which are enriched for heterochromatic histone modifications H3K9me1/me2/me3, interact with each other both and while interacting less frequently with central regions, leading to genome compartmentalization.

X Chromosome Domain Architecture Regulates Caenorhabditis elegans Lifespan but Not Dosage Compensation.

Mechanisms establishing higher-order chromosome structures and their roles in gene regulation are elusive. We analyzed chromosome architecture during nematode X chromosome dosage compensation, which represses transcription via a dosage-compensation condensin complex (DCC) that binds hermaphrodite Xs and establishes megabase-sized topologically associating domains (TADs). We show that DCC binding at high-occupancy sites (rex sites) defines eight TAD boundaries.

Dynamic Control of Chromosome Topology and Gene Expression by a Chromatin Modification.

The function of chromatin modification in establishing higher-order chromosome structure during gene regulation has been elusive. We dissected the machinery and mechanism underlying the enrichment of histone modification H4K20me1 on hermaphrodite X chromosomes during dosage compensation and discovered a key role for H4K20me1 in regulating X-chromosome topology and chromosome-wide gene expression. Structural and functional analysis of the dosage compensation complex (DCC) subunit DPY-21 revealed a novel Jumonji C demethylase subfamily that converts H4K20me2 to H4K20me1 in worms and mammals.

Dynamic Control of X Chromosome Conformation and Repression by a Histone H4K20 Demethylase.

Chromatin modification and higher-order chromosome structure play key roles in gene regulation, but their functional interplay in controlling gene expression is elusive. We have discovered the machinery and mechanism underlying the dynamic enrichment of histone modification H4K20me1 on hermaphrodite X chromosomes during C. elegans dosage compensation and demonstrated H4K20me1's pivotal role in regulating higher-order chromosome structure and X-chromosome-wide gene expression.

Chromosome-wide mechanisms to decouple gene expression from gene dose during sex-chromosome evolution.

Changes in chromosome number impair fitness by disrupting the balance of gene expression. Here we analyze mechanisms to compensate for changes in gene dose that accompanied the evolution of sex chromosomes from autosomes. Using single-copy transgenes integrated throughout the genome, we show that expression of all X-linked transgenes is balanced between XX hermaphrodites and XO males.

Influence of processing on pomegranate (Punica granatum L.) juice flavor and aroma.

Background: The objective of this study was to determine the effect of technological treatment on pomegranate juice flavor characteristics, aromatic compounds and physicochemical properties. Fresh, fresh frozen, pasteurized and reconstituted juice samples were made from Wonderful variety pomegranates. The samples were analyzed for their flavor profiles, aromatic compound content and physicochemical parameters (total soluble solids, pH, acidity and total phenolic content).

Global gene expression in Coprinopsis cinerea meiotic mutants reflects checkpoint arrest.

The basidiomycete Coprinopsis cinerea is well-suited to studies of meiosis because meiosis progresses synchronously in 10 million cells within each mushroom cap. Approximately 20% of C. cinerea genes exhibit changing expression during meiosis, but meiosis and mushroom development happen concurrently and therefore differentially expressed genes might not be directly involved in meiotic processes.