Length-length and weight-length relationships of seven deep-water fishes in the Gulf of Mexico

Regression coefficients for equations of the form Y = a + bX were estimated for total length (TL) and whole weight (W) as a function of standard length (SL) and fork length (FL) and vice versa for seven deep-water fishes. All lengths were measured in millimeters and all weights in grams. There was a significant correlation between weight and length and the types of length measurements for all species. However, the amount of variation explained by each regression varied among species. Weight-length regressions were less precise than length-length regression, as they generally are, because weights of small fish measured at sea are more inaccurate than those of large fish.Marine Scienc

Effects of task complexity on dynamic retinoscopy observations

Effects of task complexity on dynamic retinoscopy observation

Evaluating the Resilience of Face Recognition Systems Against Malicious Attacks

This paper presents an experiment designed to test the resilience of several user verification systems based on face recognition technology against simple identity spoofing methods, such as trying to gain access to the system by using mobile camera shots of the users, their ID cards, or social media photos of them that are available online. We also aim at identifying the compression threshold above which a photo can be used to gain access to the system. Four major user verification tools were tested: Keyemon and Luxand Blink on Windows and Android Face Unlock and FaceLock on Android. The results show all tested systems to be vulnerable to even very crude attacks, indicating that the technology is not ready yet for adoption in applications where security rather than user convenience is the main concern

Episodic traces and statistical regularities: Paired associate learning in typical and dyslexic readers

Learning visual-phonological associations is a key skill underlying successful reading acquisition. However, we are yet to understand the cognitive mechanisms that enable efficient learning in good readers, and those which are aberrant in individuals with developmental dyslexia. Here, we use a repeated cued-recall task to examine how typical and reading-impaired adults acquire novel associations between visual and phonological stimuli, incorporating a looking-at-nothing paradigm to probe implicit memory for target locations. Cued recall accuracy revealed that typical readers’ recall of novel phonological associates was better than dyslexic readers’ recall, and it also improved more with repetition. Eye fixation-contingent error analyses suggest that typical readers’ greater improvement from repetition reflects their more robust encoding and/or retrieval of each instance in which a given pair was presented: whereas dyslexic readers tended to recall a phonological target better when fixating its most recent location, typical readers showed this pattern more strongly when the target location was consistent across multiple trials. Thus, typical readers’ greater success in reading acquisition may derive from their better use of statistical contingencies to identify consistent stimulus features across multiple exposures. We discuss these findings in relation to the role of implicit memory in forming new visual-phonological associations as a foundational skill in reading, and areas of weakness in developmental dyslexia

The effect of resource quality on the growth of Holothuria scabra during aquaculture waste bioremediation

Reducing dependency on environmentally unsustainable formulated feeds, most of which include limited reserves of fishmeal as a protein source, is a priority for the aquaculture industry, particularly for intensive culture systems. One approach is to increase nitrogen reuse within the system by feeding nitrogen-rich aquaculture effluent to deposit feeders, thereby closing the aquaculture nitrogen-loop. This study, for the first time and on a laboratory-scale, has reared juveniles of the sea cucumber Holothuria scabra at high densities solely on particulate organic waste from a commercial-scale land-based abalone recirculating aquaculture system. Furthermore, growth rates and biomass yields were increased significantly by adjusting the effluent C:N from 5:1 to 20:1 by adding exogenous organic carbon sources (glucose, starch and cellulose), so fuelling accelerated heterotrophic bacterial production within the redox-stratified tank sediment. Sea cucumber juveniles reared solely on effluent had a biomass density of 711 g m−2 after four months whereas animals reared on starch-amended effluent (the best performing treatment) had a final density of 1011 g m−2. Further optimisation of this approach could increase biomass yields and pave the way for the commercial cultivation of deposit feeding animals on waste streams, thus contributing to more environmentally sustainable aquaculture. Here, the nitrogen that originated from fishmeal is not lost through the discharge of aquaculture effluent; rather, it is immobilised into single cell biomass that is up-cycled into high-value secondary biomass. We demonstrate that sea cucumbers can be produced at high density through the manipulation of the C:N ratio of aquaculture effluent

Gliotoxin effects on fungal growth: Mechanisms and exploitation

Although initially investigated for its antifungal properties, little is actually known about the effect of gliotoxin on Aspergillus fumigatus and other fungi. We have observed that exposure of A. fumigatus to exogenous gliotoxin (14 lg/ml), under gliotoxin-limited growth conditions, results in significant alteration of the expression of 27 proteins (up- and down-regulated >1.9-fold; p < 0.05) including de novo expression of Cu, Zn superoxide dismutase, up-regulated allergen Asp f3 expression and down-regulated catalase and a peroxiredoxin levels. Significantly elevated glutathione GSH levels (p < 0.05), along with concomitant resistance to diamide, were evident in A. fumigatus ∆gliT, lacking gliotoxin oxidoreductase, a gliotoxin self-protection gene. Saccharomyces cerevisiae deletents (∆sod1 and ∆yap1) were hypersensitive to exogenous gliotoxin, while ∆gsh1 was resistant. Significant gliotoxin-mediated (5 µg/ml) growth inhibition (p < 0.001) of Aspergillus nidulans, Aspergillus terreus, Aspergillus niger, Cochliobolus heterostrophus and Neurospora crassa was also observed. Growth of Aspergillus flavus, Fusarium graminearum and Aspergillus oryzae was significantly inhibited (p < 0.001) at gliotoxin (10 lg/ml), indicating differential gliotoxin sensitivity amongst fungi. Re-introduction of gliT into A. fumigatus DgliT, at a different locus (ctsD; AFUA_4G07040, an aspartic protease), with selection on gliotoxin, facilitated deletion of ctsD without use of additional antibiotic selection markers. Absence of ctsD expression was accompanied by restoration of gliT expression, and resistance to gliotoxin. Thus, we propose gliT/gliotoxin as a useful selection marker system for fungal transformation. Finally, we suggest incorporation of gliotoxin sensitivity assays into all future fungal functional genomic studies

Redox stratification drives enhanced growth in a deposit-feeding invertebrate: Implications for aquaculture bioremediation

Effective and affordable treatment of waste solids is a key sustainability challenge for the aquaculture industry. Here, we investigated the potential for a deposit-feeding sea cucumber, Holothuria scabra, to provide a remediation service whilst concurrently yielding a high-value secondary product in a land-based recirculating aquaculture system (RAS). The effect of sediment depth, particle size and redox regime were examined in relation to changes in the behaviour, growth and biochemical composition of juvenile sea cucumbers cultured for 81 d in manipulated sediment systems, describing either fully oxic or stratified (oxic-anoxic) redox regimes. The redox regime was the principal factor affecting growth, biochemical composition and behaviour, while substrate depth and particle size did not significantly affect growth rate or biomass production. Animals cultured under fully oxic conditions exhibited negative growth and had higher lipid and carbohydrate contents, potentially due to compensatory feeding in response to higher micro - phyto benthic production. In contrast, animals in the stratified treatments spent more time feeding, generated faster growth and produced significantly higher biomass yields (626.89 ± 35.44 g m-2 versus 449.22 ± 14.24 g m-2; mean ± SE). Further, unlike in oxic treatments, growth in the stratified treatments did not reach maximum biomass carrying capacity, indicating that stratified sediment is more suitable for culturing sea cucumbers. However, the stratified sediments may exhibit reduced bioremediation ability relative to the oxic sediment, signifying a trade-off between remediation efficiency and exploitable biomass yiel

CDK-dependent Hsp70 phosphorylation controls G1 cyclin abundance and cell-cycle progression

In budding yeast, the essential functions of Hsp70 chaperones Ssa1-4 are regulated through expression level, isoform specificity, and cochaperone activity. Suggesting a novel regulatory paradigm, we find that phosphorylation of Ssa1 T36 within a cyclin-dependent kinase (CDK) consensus site conserved among Hsp70 proteins alters cochaperone and client interactions. T36 phosphorylation triggers displacement of Ydj1, allowing Ssa1 to bind the G1 cyclin Cln3 and promote its degradation. The stress CDK Pho85 phosphorylates T36 upon nitrogen starvation or pheromone stimulation, destabilizing Cln3 to delay onset of S phase. In turn, the mitotic CDK Cdk1 phosphorylates T36 to block Cln3 accumulation in G2/M. Suggesting broad conservation from yeast to human, CDK-dependent phosphorylation of Hsc70 T38 similarly regulates Cyclin D1 binding and stability. These results establish an active role for Hsp70 chaperones as signal transducers mediating growth control of G1 cyclin abundance and activity