A review of the integration of classical biological control with other techniques to manage invasive weeds in natural areas and rangelands

Integrating classical biological control with other management techniques such as herbicide, fire, mechanical control, grazing, or plant competition, can be the most effective way to manage invasive weeds in natural areas and rangelands. Biological control agents can be protected from potential negative impacts of these weed control methods through untreated refugia or by applying the treatment at a time when the agent is not vulnerable. A literature review of experiments that integrated biological control with other management strategies from 1987 to 2017 yielded 39 terrestrial and 16 aquatic studies. The tactics most frequently integrated with biological control were herbicide applications and plant competition. Despite numerous examples of successful programs and calls for more widespread integration of biological control with other weed management strategies, there was no increase in the number of studies reported annually over time. Additional studies investigating the ecological and economic benefits of integrated weed management are needed.     

Galloway-Mowat syndrome in Taiwan: <Emphasis Type="Italic">OSGEP</Emphasis> mutation and unique clinical phenotype

Background

Galloway-Mowat syndrome (GAMOS) is a rare autosomal recessive disease characterized by the combination of glomerulopathy with early-onset nephrotic syndrome and microcephaly with central nervous system anomalies. Given its clinical heterogeneity, GAMOS is believed to be a genetically heterogenous group of disorders. Recently, it has been reported that mutations in KEOPS-encoding genes, including the OSGEP gene, were responsible for GAMOS.

Results

Overall, 6 patients from 5 different Taiwanese families were included in our study; the patients had an identical OSGEP gene mutation (c.740G?>?A transition) and all exhibited a uniform clinical phenotype with early-onset nephrotic syndrome, craniofacial and skeletal dysmorphism, primary microcephaly with pachygyria, and death before 2?years of age. We reviewed their clinical manifestations, the prenatal and postnatal presentations and ultrasound findings, results of imaging studies, associated anomalies, and outcome on follow-up. All individuals were found to have an “aged face” comprising peculiar facial dysmorphisms. Arachnodactyly or camptodactyly were noted in all patients. Neurological findings consisted of microcephaly, hypotonia, developmental delay, and seizures. Brain imaging studies all showed pachygyria and hypomyelination. All patients developed early-onset nephrotic syndrome. The proteinuria was steroid-resistant and eventually resulted in renal function impairment. Prenatal ultrasound findings included microcephaly, intrauterine growth restriction, and oligohydramnios. Fetal MRI in 2 patients confirmed the gyral and myelin abnormalities.

Conclusions

Our study suggests that a careful review of the facial features can provide useful clues for an early and accurate diagnosis. Prenatal ultrasound findings, fetal MRI, genetic counseling, and mutation analysis may be useful for an early prenatal diagnosis.

     

Cry2 Is Critical for Circadian Regulation of Myogenic Differentiation by Bclaf1-Mediated mRNA Stabilization of Cyclin D1 and Tmem176b

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Reversed predator–prey cycles are driven by the amplitude of prey oscillations

Ecoevolutionary feedbacks in predator–prey systems have been shown to qualitatively alter predator–prey dynamics. As a striking example, defense–offense coevolution can reverse predator–prey cycles, so predator peaks precede prey peaks rather than vice versa. However, this has only rarely been shown in either model studies or empirical systems. Here, we investigate whether this rarity is a fundamental feature of reversed cycles by exploring under which conditions they should be found. For this, we first identify potential conditions and parameter ranges most likely to result in reversed cycles by developing a new measure, the effective prey biomass, which combines prey biomass with prey and predator traits, and represents the prey biomass as perceived by the predator. We show that predator dynamics always follow the dynamics of the effective prey biomass with a classic ¼‐phase lag. From this key insight, it follows that in reversed cycles (i.e., ¾‐lag), the dynamics of the actual and the effective prey biomass must be in antiphase with each other, that is, the effective prey biomass must be highest when actual prey biomass is lowest, and vice versa. Based on this, we predict that reversed cycles should be found mainly when oscillations in actual prey biomass are small and thus have limited impact on the dynamics of the effective prey biomass, which are mainly driven by trait changes. We then confirm this prediction using numerical simulations of a coevolutionary predator–prey system, varying the amplitude of the oscillations in prey biomass: Reversed cycles are consistently associated with regions of parameter space leading to small‐amplitude prey oscillations, offering a specific and highly testable prediction for conditions under which reversed cycles should occur in natural systems.     

Replacement of nucleosomal histones by histone H1-like proteins during spermiogenesis in Cnidaria: Evolutionary implications

We have analyzed the chromosomal protein composition of the sperm from several species belonging to three different classes (Hydrozoa, Scyphozoa, Anthozoa) of the phylum Cnidaria. In every instance, the sperm nuclear basic proteins (SNBPs) were found to consist of one to two major protein fractions that belong to the histone H1 family, as can be deduced from their amino acid composition and solubility in dilute perchloric acid, and the presence of a trypsin-resistant core. In those species where mature spawned sperm could be obtained, we were able to show that these proteins completely replace the somatic histones from the stem cells that are present at the onset of spermatogenesis. The presence of a highly specialized histone H1 molecule in the sperm of this phylum provides support for the idea that the protamine-like proteins (PL) from higher groups in the phylogenetic tree (and possibly protamines as well) may all have evolved from a primitive histone H1 ancestor.     

Sex differences in the vertebral column of gombe chimpanzees

Male and female chimpanzees from Gombe National Park, Tanzania (Pan troglodytes schweinfurthii) differ in live body weights but not in cranial capacity or fore-and hindlimb long bone lengths. Skeletal dimensions of the limbs and vertebral column indicate a mosaic of sex differences. Vertebral column measurements generally are greater in males. While linear measurements identify differences in the breadth and depth of the lower cervical and upper thoracic vertebrae, areal assessments show significant differences in weight-bearing surfaces throughout the thoracic and lumbar segments. These can be interpreted in terms of distribution of weight and body composition (i.e. amount of musculature).     

Dynamic discarding decisions: foraging theory for high-grading in a trawl fishery

The decision by fishermen to discard or retain fish of low valueto make room for more valuable fish in the hold of a boat (high-grading)is similar to diet choice problems faced by natural foragers.In our study, we apply the rationale of diet choice theory tohigh-grading behavior in the Oregon trawl fishery by treatingfishermen as foragers who must decide how much of each net'shaul to "ingest" before searching for more prey. We derive astate-dependent, temporal model of discarding behavior withina fishing trip. This optimization considers the availabilityof differently valued fish, trip quotas set by the regulatoryagency, and the risk of premature trip termination due to lossof gear or injury. The results indicate that those parametersaffect discarding behavior through their effect on the probabilityof exceeding the allowable catch, which we consider analogousto gut capacity. High-grading (partial prey consumption) occurredthroughout many simulated trips. The predictions were consistentwith the trends in discarding observed in the Oregon trawl fleet.Behavioral models such as ours can be useful to fishery managersby providing a means to explore the potential responses of fishermento new regulations before they are implemented.     

Histology and lectin-binding patterns in the skin of the terrestrial horned frog Ceratophrys ornata

The terrestrial horned frog, Ceratophrys ornata, lives on a wet substratum and absorbs water through the ventral epidermis; water is lost by evaporation from the dorsal skin. Thus, this species may be useful as a model for determining whether or not skin histology and lectin-binding patterns, indicative of glycoconjugates, are related to skin functions such as osmoregulation and water balance. With this in mind, a histological and lectin-histochemical study was carried out on dorsal and ventral skin of aquatic tadpoles and of a young terrestrial frog of C. ornata. Sections of skin were stained with various dyes to demonstrate general histological features and with two horseradish peroxidase (HRP)-conjugated lectins, Ulex europaeus agglutinin (UEA 1) and soybean agglutinin (SBA) which bind to specific terminal sugar residues of glycoconjugates, namely L-fucose and N-acetyl-D-galactosamine or D-galactose, respectively. In early stage tadpoles both lectin-binding patterns were similar in the bilaminar epidermis of dorsal and ventral skin (i.e., each lectin stained the apical cell layer). However, metamorphic changes resulted in a young frog with typical adult-type skin composed of a stratified squamous epidermis and three distinct types of glands containing glycoconjugates in their secretions. Strikingly different lectin-binding patterns were evident in the epidermis from dorsal and ventral regions of the body. The epidermis from the dorsal region was stained by both lectins; in contrast, that from the ventral region although stained strongly by HRP-SBA, did not react with HRP-UEA 1 indicating that few, if any, fucose residues were present in the ventral epidermis. These findings, as suggested in the discussion, indicate that different glycoconjugate patterns in dorsal and ventral skin may be associated with the regulation of water balance in the frog.