Using voluntary agreements to exclude stock from waterways: an evaluation of project success and persistence

Agriculture is one of the major drivers of ecological degradation in river basins. Excluding stock (cows and sheep) from grazing riverbanks and accessing rivers is one of the most common river restoration activities. To be effective, stock exclusion must be maintained indefinitely. In Australia, and elsewhere, stock exclusion projects are most commonly implemented by establishing voluntary agreements between landholders and government agencies. This study examined the extent to which landholders in 3 catchment management authority (CMA) regions in southeast Australia maintain stock exclusion from waterways, whether vegetation on riverbanks recovered, and the effectiveness of assessment methods. It was found that nearly half of landholders continue to graze stock on the riverbank. There has been some success with improving the condition of riparian vegetation. Sites with full stock exclusion contain the pre-European abundance of juvenile trees, and sites with continued grazing contain significantly lower abundance of juvenile trees. Establishing the effectiveness of management was made more difficult by the inconsistent methods used by the different CMAs. Stock exclusion projects implemented with voluntary agreements have the potential to succeed if oversight is improved between government agencies and CMAs and between CMAs and landholders. Projects will be easier to assess if regional authorities use consistent methods of assessment. Voluntary agreements are only suitable for environmental management if projects are monitored, maintained, and assessed appropriately

Chromatin Organization in Sperm May Be the Major Functional Consequence of Base Composition Variation in the Human Genome

Chromatin in sperm is different from that in other cells, with most of the genome packaged by protamines not nucleosomes. Nucleosomes are, however, retained at some genomic sites, where they have the potential to transmit paternal epigenetic information. It is not understood how this retention is specified. Here we show that base composition is the major determinant of nucleosome retention in human sperm, predicting retention very well in both genic and non-genic regions of the genome. The retention of nucleosomes at GC-rich sequences with high intrinsic nucleosome affinity accounts for the previously reported retention at transcription start sites and at genes that regulate development. It also means that nucleosomes are retained at the start sites of most housekeeping genes. We also report a striking link between the retention of nucleosomes in sperm and the establishment of DNA methylation-free regions in the early embryo. Taken together, this suggests that paternal nucleosome transmission may facilitate robust gene regulation in the early embryo. We propose that chromatin organization in the male germline, rather than in somatic cells, is the major functional consequence of fine-scale base composition variation in the human genome. The selective pressure driving base composition evolution in mammals could, therefore, be the need to transmit paternal epigenetic information to the zygote

Identification of Novel Functional Inhibitors of Acid Sphingomyelinase

We describe a hitherto unknown feature for 27 small drug-like molecules, namely functional inhibition of acid sphingomyelinase (ASM). These entities named FIASMAs (Functional Inhibitors of Acid SphingoMyelinAse), therefore, can be potentially used to treat diseases associated with enhanced activity of ASM, such as Alzheimer's disease, major depression, radiation- and chemotherapy-induced apoptosis and endotoxic shock syndrome. Residual activity of ASM measured in the presence of 10 µM drug concentration shows a bimodal distribution; thus the tested drugs can be classified into two groups with lower and higher inhibitory activity. All FIASMAs share distinct physicochemical properties in showing lipophilic and weakly basic properties. Hierarchical clustering of Tanimoto coefficients revealed that FIASMAs occur among drugs of various chemical scaffolds. Moreover, FIASMAs more frequently violate Lipinski's Rule-of-Five than compounds without effect on ASM. Inhibition of ASM appears to be associated with good permeability across the blood-brain barrier. In the present investigation, we developed a novel structure-property-activity relationship by using a random forest-based binary classification learner. Virtual screening revealed that only six out of 768 (0.78%) compounds of natural products functionally inhibit ASM, whereas this inhibitory activity occurs in 135 out of 2028 (6.66%) drugs licensed for medical use in humans