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1.
Insects ; 13(3)2022 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-35323567

RESUMO

Global markets do not tolerate the presence of fruit fly (Tephritidae) in horticultural produce. A key method of control for tephritidae pests, is the sterile insect technique (SIT). Several countries release a bisex strain, i.e., males and females, however the sterile male is the only sex which contributes to wild population declines when released en masse. In commercial orchards, there are concerns that sterile females released as part of bisex strains, may oviposit, i.e., 'sting' and cause damage to fruit, rendering it unmarketable. Australia has released a bisex strain of sterile Queensland fruit fly, Bactrocera tryoni Froggatt, for several decades to suppress wild pest populations, particularly in peri-urban and urban environments. Here, we assessed fruit damage in two commercially grown stone fruit orchards where bisex sterile B. tryoni were released, and in an orchard that did not receive sterile flies. The number of detected stings were higher in only one SIT release orchard, compared with the control; however, there was no difference between SIT and control orchards in the number of larvae detected. We showed that there is no evidence that sterile female B. tryoni released in large numbers caused stings, or damage that led to downgraded or unsaleable fruit. The bisex strain of sterile B. tryoni is recommended for use in commercial stone-fruit orchards, under the conditions in which this trial was conducted.

2.
Transp Res Part A Policy Pract ; 154: 300-312, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34703083

RESUMO

The COVID-19 pandemic has challenged and encouraged local governments to reallocate street space. The chief purpose of new regimes of street management is to expand spaces for walking and bicycling, and to ease business interactions such as curbside pickup and dining while maintaining social distancing guidelines. We investigated how North Americans on Twitter viewed alternative uses and forms of street reallocation, specifically during the early months of the pandemic from April 1, 2020 to July 1, 2020. Relying on a crowdsourced dataset of government actions (Combs and Pardo 2021), we identified five areas of policy initiative that were broadly representative of government actions: cycling, walking, driving, business, and curbside. First, we identified a corpus of 292,108 geolocated tweets from the U.S. and Canada. Next, we used word vectors, built on this Twitter corpus, to generate similarity scores across the five areas of policy initiative for each tweet. Finally, we selected the top tweets that closely matched ideas contained in the areas of policy initiative, thus creating a finer corpus of 1,537 tweets. Using the five categories as guideposts, we conducted an inductive content analysis to understand opinions expressed on Twitter. Our analysis suggests that renewed use of the curb has opened up possibilities for reimaging this space. Particularly, business uses of the curb for dining and pick up zones have expanded widely, and there is more use of sidewalks; yet both spaces have limited capacity. Planners need to think of expanding these assets while reducing cost burdens for their alternative uses.

3.
Sci Rep ; 11(1): 17632, 2021 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-34480052

RESUMO

Sterile male Queensland fruit fly, Bactrocera tryoni (Froggatt), fed as immature adults on the plant compound raspberry ketone (RK), show a reduced attraction to cuelure, a synthetic analogue of RK used as an attractant in Male Annihilation Technique. We hypothesized the reduced attraction of RK-fed adult males to cuelure may be a consequence of altered expression of chemoreception genes. A Y-tube olfactometer assay with RK-fed and RK-unfed sterile B. tryoni males tested the subsequent behavioural response to cuelure. Behavioral assays confirmed a significant decrease in attraction of RK-fed sterile males to cuelure. RK-fed, non-responders (to cue-lure) and RK-unfed, responders (to cue-lure) males were sampled and gene expression compared by de novo RNA-seq analysis. A total of 269 genes in fly heads were differentially expressed between replicated groups of RK-fed, cuelure non-responders and RK-unfed, cuelure responders. Among them, 218 genes including 4 chemoreceptor genes were up regulated and 51 genes were down regulated in RK-fed, cuelure non-responders. De novo assembly generated many genes with unknown functions and no significant BLAST hits to homologues in other species. The enriched and suppressed genes reported here, shed light on the transcriptional changes that affect the dynamics of insect responses to chemical stimuli.


Assuntos
Butanonas , Células Quimiorreceptoras/metabolismo , Suplementos Nutricionais , Regulação da Expressão Gênica , Infertilidade Masculina/metabolismo , Tephritidae/metabolismo , Animais , Masculino
4.
BMJ Case Rep ; 14(5)2021 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-33986013

RESUMO

A 52-year-old long-term user of the levonorgestrel-releasing intrauterine system (LNG-IUS) presented with vaginal bleeding. Endometrial biopsy was performed and revealed endometrioid adenocarcinoma. The patient had a laparoscopic hysterectomy and bilateral salpingo-oophorectomy. Endometrial cancer is rare in women with LNG-IUS as only seven cases have been published in the literature. Although scientific evidence shows LNG-IUS has a protective effect on the endometrium from developing cancer, our report highlights the importance of clinicians to be vigilant in cases of women with LNG-IUS who develop intermittent vaginal bleeding.


Assuntos
Anticoncepcionais Femininos , Neoplasias do Endométrio , Dispositivos Intrauterinos Medicados , Anticoncepcionais Femininos/efeitos adversos , Endométrio , Feminino , Humanos , Dispositivos Intrauterinos Medicados/efeitos adversos , Levanogestrel/efeitos adversos , Pessoa de Meia-Idade , Hemorragia Uterina/induzido quimicamente
5.
Meat Sci ; 168: 108193, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32474364

RESUMO

Beef ageing (in vacuo) for tenderisation and flavour development may be accelerated by favourable temperature-time combinations (TTCs), however the effect of such manipulations on volatile organic compounds (VOCs) that are generated during cooking, is unknown. We compared VOCs from grilled beef longissimus lumborum muscle samples which had been subjected to different TTCs. The TTCs consisted of combinations of temperatures (~ 3, 5, or 7 °C) and ageing time periods (6, 8, 10 or 12 d); as well as control samples, which were held at 0-2 °C for a total of 14 d. Sensory quality attributes of these same samples were measured by untrained consumer panellists. Generally, it was found that TTCs had negligible effects on grilled beef VOCs and were comparable to controls. Furthermore, many VOCs were significantly related to flavour intensity, flavour liking and overall liking. These findings support the use of TTCs as a viable means to accelerate the rate of beef ageing without compromising quality.


Assuntos
Manipulação de Alimentos/métodos , Carne Vermelha/análise , Compostos Orgânicos Voláteis/análise , Adulto , Animais , Austrália , Bovinos , Comportamento do Consumidor , Culinária , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético , Temperatura , Fatores de Tempo
6.
J Texture Stud ; 51(4): 559-566, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32259282

RESUMO

In this study, the relationship between sensory evaluation and several objective metrics of beef tenderness was tested. Objective metrics included shear force, sarcomere length, collagen content, myofibrillar, and sarcoplasmic protein solubility and particle size analysis. These results were compared to consumer panel scores of tenderness for the same aged beef striploin (longissimus lumborum muscle) samples. There was found to be a significant relationship between sarcomere length, shear force, and particle size with tenderness scores. Collagen content and protein solubilities were not associated to tenderness scores (p > 0.05). Sarcomere length contributions for explaining tenderness variation were overlapped by the contributions of shear force (collinearity). Independent models demonstrated that the lower 95% confidence interval of the fitted regression line exceeded 50% acceptance of tenderness when shear force values <42.6 N and when particle size values <198 µm. We can recommend these as thresholds for consumer acceptance of beef tenderness, although considerations of sample type, analytical methodology, and consumer demographics should be made prior to their adoption. This provision was based on the variation in tenderness scores evident between individual panelists and experimental striploins.


Assuntos
Colágeno/química , Carne , Fenômenos Mecânicos , Sarcômeros/química , Adolescente , Adulto , Animais , Austrália , Benchmarking , Bovinos , Culinária , Feminino , Tecnologia de Alimentos , Humanos , Masculino , Pessoa de Meia-Idade , Tamanho da Partícula , Proteínas , Solubilidade , Paladar , Adulto Jovem
7.
Insect Sci ; 27(4): 745-755, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30848568

RESUMO

Queensland fruit fly [Bactrocera tryoni (Froggatt), Diptera, Tephritidae] is the most devastating insect pest impacting Australian horticulture. The Sterile Insect Technique (SIT) is an important component of tephritid pest management programs. However, mass-rearing and irradiation (to render insects sterile) may reduce the fitness and performance of the insect, including the ability of sterile males to successfully compete for wild females. Manipulation of the gut microbiome, including the supplementation with bacterial probiotics shows promise for enhancing the quality of mass-reared sterile flies, however there are fewer published studies targeting the larval stage. In this study, we supplemented the larval stage of mass-reared B. tryoni with bacterial probiotics. We tested several individual bacteria that had been previously isolated and characterized from the gut of wild B. tryoni larvae including Asaia sp., Enterobacter sp., Lactobacillus sp., Leuconostoc sp. We also tested a consortium of all four of these bacterial isolates. The fitness parameters tested included adult survival in field cages, laboratory mate selection of bacteria supplemented males by bacteria nonsupplemented females, and laboratory locomotor activity of adult flies. None of the bacterial probiotic treatments in the current study was significantly different to the control for field survival, mate selection or locomotor activity of adult B. tryoni, which agree with some of the other studies regarding bacterial probiotics fed to the larval stage of tephritids. Future work is needed to determine if feeding the same, and/or other probiotics to adults, as opposed to larvae can positively impact survival, mating performance, mating competitiveness and locomotor activity of B. tryoni. The bacterial group(s) and function of bacterial species that increase fitness and competitiveness is also of interest to tephritid mass-rearing programs.


Assuntos
Preferência de Acasalamento Animal/efeitos dos fármacos , Probióticos/administração & dosagem , Tephritidae/efeitos dos fármacos , Ração Animal/análise , Animais , Dieta , Feminino , Larva/efeitos dos fármacos , Larva/crescimento & desenvolvimento , Larva/fisiologia , Locomoção/efeitos dos fármacos , Longevidade/efeitos dos fármacos , Masculino , Tephritidae/crescimento & desenvolvimento , Tephritidae/fisiologia
8.
BMC Biotechnol ; 19(Suppl 2): 95, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31847841

RESUMO

BACKGROUND: The Queensland fruit fly, Bactrocera tryoni (Froggatt) (Diptera, Tephritidae) is the most significant insect pest of Australian horticulture. Bactrocera tryoni is controlled using a range of tools including the Sterile Insect Technique (SIT). Mass-rearing and irradiation of pupae in SIT can reduce the fitness and quality of the released sterile insects. Studies have also showed reduced microbial gut diversity in domesticated versus wild tephritids. RESULTS: Transmission electron microscopy confirmed the presence of the bacterial isolates in the mid-gut of mass-reared larvae, and plate counts from individual larval guts showed increased numbers of bacteria in supplemented larvae. Several developmental and fitness parameters were tested including larval development time (egg-hatch to pupation), pupal weight, emergence, flight ability, sex-ratio, and time to adult eclosion (egg-hatch to adult eclosion). Enterobacter sp. and Asaia sp. shortened larval development time, while this was delayed by Lactobacillus sp., Leuconostoc sp. and a blend of all four bacteria. The mean time from egg hatch to adult eclosion was significantly reduced by Leuconostoc sp. and the blend for males and females, indicating that the individual bacterium and consortium affect flies differently depending on the life stage (larval or pupal). There was no impact of bacterial supplemented larvae on pupal weight, emergence, flight ability, or sex ratio. CONCLUSIONS: Our findings show that bacteria fed to the larval stage of B. tryoni can impart fitness advantages, but the selection of probiotic strains (individual or a consortium) is key, as each have varying effects on the host. Bacteria added to the larval diet particularly Leuconostoc sp. and the blend have the capacity to reduce costs and increase the number of flies produced in mass-rearing facilities by reducing time to adult eclosion by 1.3 and 0.8 mean days for males, and 1.2 and 0.8 mean days for females.


Assuntos
Ração Animal/microbiologia , Bactérias/classificação , RNA Ribossômico 16S/genética , Tephritidae/fisiologia , Animais , Bactérias/genética , Bactérias/crescimento & desenvolvimento , DNA Bacteriano/genética , DNA Ribossômico/genética , Feminino , Microbioma Gastrointestinal , Aptidão Genética , Controle de Insetos , Larva/microbiologia , Larva/fisiologia , Masculino , Microscopia Eletrônica de Transmissão , Filogenia , Comportamento Sexual Animal , Tephritidae/microbiologia
9.
BMC Microbiol ; 19(Suppl 1): 281, 2019 12 24.
Artigo em Inglês | MEDLINE | ID: mdl-31870300

RESUMO

BACKGROUND: Mass-rearing, domestication and gamma irradiation of tephritid fruit flies used in sterile insect technique (SIT) programmes can negatively impact fly quality and performance. Symbiotic bacteria supplied as probiotics to mass-reared fruit flies may help to overcome some of these issues. However, the effects of tephritid ontogeny, sex, diet and irradiation on their microbiota are not well known. RESULTS: We have used next-generation sequencing to characterise the bacterial community composition and structure within Queensland fruit fly, Bactrocera tryoni (Froggatt), by generating 16S rRNA gene amplicon libraries derived from the guts of 58 individual teneral and mature, female and male, sterile and fertile adult flies reared on artificial larval diets in a laboratory or mass-rearing environment, and fed either a full adult diet (i.e. sugar and yeast hydrolysate) or a sugar only adult diet. Overall, the amplicon sequence read volume in tenerals was low and smaller than in mature adult flies. Operational taxonomic units (OTUs), belonging to the families Enterobacteriaceae (8 OTUs) and Acetobacteraceae (1 OTU) were most prevalent. Enterobacteriaceae dominated laboratory-reared tenerals from a colony fed a carrot-based larval diet, while Acetobacteraceae dominated mass-reared tenerals from a production facility colony fed a lucerne chaff based larval diet. As adult flies matured, Enterobacteriaceae became dominant irrespective of larval origin. The inclusion of yeast in the adult diet strengthened this shift away from Acetobacteraceae towards Enterobacteriaceae. Interestingly, irradiation increased 16S rRNA gene sequence read volume. CONCLUSIONS: Our findings suggest that bacterial populations in fruit flies experience significant bottlenecks during metamorphosis. Gut bacteria in teneral flies were less abundant and less diverse, and impacted by colony origin. In contrast, mature adult flies had selectively increased abundances for some gut bacteria, or acquired these bacteria from the adult diet and environment. Furthermore, irradiation augmented bacterial abundance in mature flies. This implies that either some gut bacteria were compensating for damage caused by irradiation or irradiated flies had lost their ability to regulate bacterial load. Our findings suggest that the adult stage prior to sexual maturity may be ideal to target for probiotic manipulation of fly microbiota to increase fly performance in SIT programmes.


Assuntos
Bactérias/classificação , Microbioma Gastrointestinal/efeitos da radiação , RNA Ribossômico 16S/genética , Tephritidae/fisiologia , Ração Animal , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/efeitos da radiação , DNA Bacteriano/genética , DNA Ribossômico/genética , Domesticação , Feminino , Sequenciamento de Nucleotídeos em Larga Escala , Masculino , Filogenia , Análise de Sequência de RNA , Tephritidae/microbiologia , Tephritidae/efeitos da radiação
10.
Meat Sci ; 157: 107876, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31255899

RESUMO

Temperature-time combinations (TTC) effects on beef fatty acid (FA) composition, moisture content and oxidative traits were investigated. TTC were designed so temperatures were constant over each time period, and there was at most one variation in temperature within a sample's combined (total) time period. Therefore, three temperatures (~ 3, 5 and 7 °C) and five time periods (6, 8, 10 and 12 d) resulted in 72 different TTC, which were compared to control samples held for 14 d at ~ 1 °C. It was found that moisture losses increased as TTC temperature and time periods increased. There were negligible effects of TTC on FA composition. Sample TBARS and vitamin E content did not respond to TTC. A positive relationship between beef vitamin E and long chain polyunsaturated FA contents was observed. We concluded that TTC could be applied to accelerate the rate of ageing for beef and achieve comparable yield, oxidative and FA characteristics compared to conventional ageing approaches.


Assuntos
Manipulação de Alimentos/métodos , Carne Vermelha/análise , Temperatura , Fatores de Tempo , Animais , Bovinos , Ácidos Graxos/análise , Músculo Esquelético/química , Oxirredução , Substâncias Reativas com Ácido Tiobarbitúrico/análise , Vitamina E/análise , Água/química
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