Reproductive performance and offspring quality of non-ablated Pacific white shrimp (Litopenaeus vannamei) under intensive commercial scale conditions

This study evaluated reproductive performance of non-ablated Litopenaeus vannamei and the quality of their offspring under commercial conditions. Five tanks were stocked with non-ablated female and other five with ablated individuals as control. Two different larval rearing trials (Larviculture I and II) have been conducted. Six larviculture tanks (n = 3) were used on the first trial (LI) and ten for the second one (LII) (n = 3). Postlarvae from LII were used for nursery and grow-out. Spawning event and hatching rate per day were similar between both treatments. Mating success, mortality of female and number of eggs and nauplii per tank per day of non-ablated group were significantly lower than ablated female. Non-ablated female fecundity (number of eggs and nauplii per spawned female per day) was significantly higher than control. There was no significant difference between daily larval stage index of larvae in LI and LII. The response to the salinity stress test, and final survival and weight in LI was similar. However in LII, postlarvae derived from non-ablated had significantly higher survival to salinity stress test. Identical survival, final weight, weekly growth, feed conversion rate and yield were observed in nursery. The same was observed in grow-out, including weight gain and specific growth rate. Overall this study demonstrates that non-ablated females can have comparable level of productivity to ablated females in intensive commercial hatchery conditions. Their offspring perform comparably in all culture stages with evidence of enhanced resistance to stress in larvae derived from non-ablated female broodstock

A cellular automaton model of crystalline cellulose hydrolysis by cellulases

<p>Abstract</p> <p>Background</p> <p>Cellulose from plant biomass is an abundant, renewable material which could be a major feedstock for low emissions transport fuels such as cellulosic ethanol. Cellulase enzymes that break down cellulose into fermentable sugars are composed of different types - cellobiohydrolases I and II, endoglucanase and β-glucosidase - with separate functions. They form a complex interacting network between themselves, soluble hydrolysis product molecules, solution and solid phase substrates and inhibitors. There have been many models proposed for enzymatic saccharification however none have yet employed a cellular automaton approach, which allows important phenomena, such as enzyme crowding on the surface of solid substrates, denaturation and substrate inhibition, to be considered in the model.</p> <p>Results</p> <p>The Cellulase 4D model was developed <it>de novo </it>taking into account the size and composition of the substrate and surface-acting enzymes were ascribed behaviors based on their movements, catalytic activities and rates, affinity for, and potential for crowding of, the cellulose surface, substrates and inhibitors, and denaturation rates. A basic case modeled on literature-derived parameters obtained from <it>Trichoderma reesei </it>cellulases resulted in cellulose hydrolysis curves that closely matched curves obtained from published experimental data. Scenarios were tested in the model, which included variation of enzyme loadings, adsorption strengths of surface acting enzymes and reaction periods, and the effect on saccharide production over time was assessed. The model simulations indicated an optimal enzyme loading of between 0.5 and 2 of the base case concentrations where a balance was obtained between enzyme crowding on the cellulose crystal, and that the affinities of enzymes for the cellulose surface had a large effect on cellulose hydrolysis. In addition, improvements to the cellobiohydrolase I activity period substantially improved overall glucose production.</p> <p>Conclusions</p> <p>Cellulase 4D simulates the enzymatic hydrolysis of cellulose to glucose by surface and solution phase-acting enzymes and accounts for complex phenomena that have previously not been included in cellulose hydrolysis models. The model is intended as a tool for industry, researchers and educators alike to explore options for enzyme engineering and process development and to test hypotheses regarding cellulase mechanisms.</p

Prophylactic properties of biofloc- or Nile tilapia-conditioned water against Vibrio parahaemolyticus infection of whiteleg shrimp (Penaeus vannamei)

Isolates of Vibrio parahaemolyticus (VpAHPND) that carry a plasmid encoding two Pir-like toxins cause acute hepatopancreatic necrosis disease (AHPND), a disease that has caused devastating economic losses to the shrimp industry, particularly in Asia. However, lower prevalence of AHPND infection has been associated with farms that operate with biofloc or lower salinity culture water. Therefore, the aim of this present study was to investigate the effects of biofloc and Nile tilapia (Oreochromis niloticus)-conditioned water prepared at different culture water salinities on survival of whiteleg shrimp (Penaeus vannamei) bath-challenged experimentally with VpAHPND. First, groups of shrimp were bath-challenged with VpAHPND in clear 15 ppt seawater (CW) or in the presence of a pre-cultured biofloc at 25%, 50% and 100% (v/v). Survival during 96 h post-challenge was significantly greater in groups cultured in 50% and 100% biofloc (p

Artists on the edge of the world : An integrated approach to the study of Magdalenian engraved stone plaquettes from Jersey (Channel Islands)

The Upper Palaeolithic is characterised by the appearance of iconographic expressions most often depicting animals, including anthropomorphic forms, and geometric signs. The Late Upper Palaeolithic Magdalenian saw a flourishing of such depictions, encompassing cave art, engraving of stone, bone and antler blanks and decoration of tools and weapons. Though Magdalenian settlement exists as far northwest as Britain, there is a limited range of art known from this region, possibly associated with only fleeting occupation of Britain during this period. Stone plaquettes, flat fragments of stone engraved on at least one surface, have been found in large quantities at numerous sites spanning the temporal and geographical spread of the Magdalenian, but they have been absent so far from the archaeological record of the British Isles. Between 2015 and 2018, ten fragments of stone plaquettes extensively engraved with abstract designs were uncovered at the Magdalenian site of Les Varines, Jersey, Channel Islands. In this paper, we report detailed analyses of these finds, which provide new evidence for technologies of abstract mark-making, and their significance within the lives of people on the edge of the Magdalenian world. These engraved stone fragments represent important, rare evidence of artistic expression in what is the far northern and western range of the Magdalenian and add new insight to the wider significance of dynamic practices of artistic expression during the Upper Palaeolithic

Multiply-connected Bose-Einstein condensed alkali gases: Current-carrying states and their decay

The ability to support metastable current-carrying states in multiply-connected settings is one of the prime signatures of superfluidity. Such states are investigated theoretically for the case of trapped Bose condensed alkali gases, particularly with regard to the rate at which they decay via thermal fluctuations. The lifetimes of metastable currents can be either longer or shorter than experimental time-scales. A scheme for the experimental detection of metastable states is sketched.Comment: 4 pages, including 1 figure (REVTEX

Variation in white-tailed deer antler size: the effects of age, landscape composition, and physiographic province.

Spatial variation in landscape composition can influence phenotypic expression in wildlife species and can improve management efforts to express certain phenotypic traits. We evaluated the influence of age, landscape composition, and physiographic province on white-tailed deer (Odocoileus virginianus) antler characteristics using data from 16,622 male deer (age range: 1.5–3.5+ years old) harvested between 1997–2016 across five physiographic provinces in Georgia. Age and physiographic province influenced antler size index (ASI; P \u3c 0.001). ASI of yearling males was greatest (- x = 53.37; SE = 0.39) in the Upper Coastal Plain and least (- x = 46.23; SE = 0.51) in the Lower Coastal Plain physiographic province. Given the differences in ASI among physiographic provinces, we evaluated how landscape composition within each physiographic province influenced ASI of 7,325 yearling (1.5-year-old) males. Yearling ASI was positively related to increasing coverage of cultivated crops and suburban-urban areas (e.g., parks, small housing developments). Conversely, evergreen and deciduous forested cover consistently had a negative effect on ASI, except in the Ridge and Valley physiographic province where evergreen was positively related to ASI. Wildlife managers and hunters should recognize the effects of age, landscape composition, and physiographic province when setting antler size expectations

Rater Reliability of the Hardy Classification for Pituitary Adenomas in the Magnetic Resonance Imaging Era

Objectives The Hardy classification is used to classify pituitary tumors for clinical and research purposes. The scale was developed using lateral skull radiographs and encephalograms, and its reliability has not been evaluated in the magnetic resonance imaging (MRI) era. Design Fifty preoperative MRI scans of biopsy-proven pituitary adenomas using the sellar invasion and suprasellar extension components of the Hardy scale were reviewed. Setting This study was a cohort study set at a single institution. Participants There were six independent raters. Main Outcome Measures The main outcome measures of this study were interrater reliability, intrarater reliability, and percent agreement. Results Overall interrater reliability of both Hardy subscales on MRI was strong. However, reliability of the intermediate scores was weak, and percent agreement among raters was poor (12-16%) using the full scales. Dichotomizing the scale into clinically useful groups maintained strong interrater reliability for the sellar invasion scale and increased the percent agreement for both scales. Conclusion This study raises important questions about the reliability of the original Hardy classification. Editing the measure to a clinically relevant dichotomous scale simplifies the rating process and may be useful for preoperative tumor characterization in the MRI era. Future research studies should use the dichotomized Hardy scale (sellar invasion Grades 0-III versus Grade IV, suprasellar extension Types 0-C versus Type D)

Antibiotic prescribing in patients with self-reported sore throat.

Objectives: To investigate the predictors of general practitioner (GP) consultation and antibiotic use in those developing sore throat. Methods: We conducted a prospective population-based cohort study on 4461 participants in two rounds (2010-11) from 1897 households. Results: Participants reported 2193 sore throat illnesses, giving a community sore throat incidence of 1.57/ person-year. 13% of sore throat illnesses led to a GP consultation and 56% of these consultations led to antibiotic use. Participants most likely to have sore throats included women and children (e.g. school compared with retirement age); adjusted incidence rate ratio (aIRR) of 1.33 and 1.52, respectively. Participants with sore throat were more likely to consult their GP if they were preschool compared with retirement age [adjusted OR (aOR) 3.22], had more days of sore throat (aOR 1.11), reported more severe pain (aOR 4.24) or reported fever (aOR 3.82). Antibiotics were more often used by chronically ill individuals (aOR 1.78), those reporting severe pain (aOR 4.14), those reporting fever (aOR 2.58) or children with earache (aOR 1.85). Among those who consulted, males and adults who reported feeling anxious were more likely to use antibiotics; aOR 1.87 and 5.36, respectively. Conclusions: Only 1 in 10 people who have a sore throat see a doctor and more than half of those attending get antibiotics. Further efforts to curb antibiotic use should focus on reducing initial GP consultations through public information promoting safe self-management, targeted at groups identified above as most likely to attend with sore throats

Modulation of anabolic and catabolic responses via a porous polymer scaffold manufactured using thermally induced phase separation

We describe two studies encompassing the iterative refinement of a polymer-based rhBMP-2 delivery system for bone tissue engineering. Firstly, we compared the boneforming capacity of porous poly(D,L-lactic-co-glycolic acid) (PLGA) scaffolds produced by thermally induced phase separation (TIPS) with non-porous solvent cast poly(D,L-lactic acid) (PDLLA) used previously. Secondly, we examined the potential synergy between rhBMP-2 and local bisphosphonate in the PLGA scaffold system. In vivo ectopic bone formation studies were performed in C57BL6/J mice. Polymer scaffolds containing 0, 5, 10 or 20 μg rhBMP-2 were inserted into the dorsal musculature. At all rhBMP-2 doses, porous PLGA produced significantly higher bone volume (BV, mm) than the solid PDLLA scaffolds. Next, porous PLGA scaffolds containing 10μg rhBMP-2 ±0.2, or 2μg zoledronic acid (ZA) were inserted into the hind-limb musculature. Co-delivery of local 10μg rhBMP-2/2μg ZA significantly augmented bone formation compared with rhBMP-2 alone (400 % BV increase, p < 0.01). Hydroxyapatite microparticle (HAp) addition (2% w/w) to the 10μg rhBMP-2/0.2μg ZA group increased BV (200 %, p < 0.01). We propose that this was due to controlled ZA release of HAp-bound ZA. Consistent with this, elution analyses showed that HAp addition did not alter the rhBMP-2 elution, but delayed ZA release. Moreover, 2 % w/w HAp addition reduced the scaffold's compressive properties, but did not alter ease of surgical handling. In summary, our data show that refinement of the polymer selection and scaffold fabrication can enhance rhBMP-2 induced bone formation in our bone tissue engineering implant, and this can be further optimised by the local co-delivery of ZA/HAp