922 research outputs found
Effect of multimodal cues from a predatory fish on refuge use and foraging on an amphidromous shrimp
Background. Prey can alter their behavior when detecting predator cues. Little is known about which sensory channel, number of channels, or the interaction among channels that shrimp species use to evaluate the threat from predators. The amphidromous shrimp Xiphocaris elongata has an induced defense, an elongated rostrum, where predatory fishes are present. We sought to test if kairomones or visual cues when presented singly from fish either eating flakes or shrimp, had more effect on altering the temporal feeding and refuge use patterns of long-rostrum (LR) X. elongata. We were also interested in elucidating potential interactions among cues when presented simultaneously in different combinations (kairomones + visual + mechanosensory, kairomones + alarm + visual, kairomones + alarm, kairomones + visual) on the same response variables. We expected that when presented alone kairomones will significantly increase refuge use and decrease foraging, particularly late at night, in comparison to visual cues alone, and that multiple cues when presented simultaneously will further increase refuge use and decrease foraging at night. Methods. We exposed shrimp to individual or multiple cues from the predatory fish mountain mullet, Augonostomus monticola. We examined shrimp behavior with respect to refuge use and foraging activity during four time periods (after sunset, nighttime, sunrise, and sunset) in a 24-hour period. Results. Shrimp presented fish visual and chemical cues singly did not differ from one another but differed from control shrimp (no cues) with respect to refuge use or foraging. The number of shrimp using refuge in the treatment with most cues (KVM: Kairomones+ visual + mechanosensory) was higher than in all the treatments with less cues. A significant decline in foraging was observed when multiple cues were presented simultaneously. The highest number of shrimp foraged one hour after sunset and at nighttime. A significant interaction was observed between cue treatments and time periods, with shrimp in the KVM treatment foraging less and using more refuge late at night and at sunrise than shrimp in other treatments or time periods. Conclusions. The observation that fish chemical and visual cues when presented singly produced similar refuge use and foraging patterns was contrary to expectation and suggests that visual and chemical cues, when presented alone, provide redundant information to X. elongata with regards to predation threat. The significant increase in refuge use and reduction in foraging observed in the KVM treatment suggest multimodal signal enhancement in the perception of threat. This makes evolutionary sense in \u27\u27noisy\u27\u27 environments, such as streams, where detection, localization, and intention of predators is much improved when cues are received through multiple sensory channels
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Multi-omic Analyses of Extensively Decayed Pinus contorta Reveal Expression of a Diverse Array of Lignocellulose-Degrading Enzymes.
Fungi play a key role cycling nutrients in forest ecosystems, but the mechanisms remain uncertain. To clarify the enzymatic processes involved in wood decomposition, the metatranscriptomics and metaproteomics of extensively decayed lodgepole pine were examined by RNA sequencing (RNA-seq) and liquid chromatography-tandem mass spectrometry (LC-MS/MS), respectively. Following de novo metatranscriptome assembly, 52,011 contigs were searched for functional domains and homology to database entries. Contigs similar to basidiomycete transcripts dominated, and many of these were most closely related to ligninolytic white rot fungi or cellulolytic brown rot fungi. A diverse array of carbohydrate-active enzymes (CAZymes) representing a total of 132 families or subfamilies were identified. Among these were 672 glycoside hydrolases, including highly expressed cellulases or hemicellulases. The CAZymes also included 162 predicted redox enzymes classified within auxiliary activity (AA) families. Eighteen of these were manganese peroxidases, which are key components of ligninolytic white rot fungi. The expression of other redox enzymes supported the working of hydroquinone reduction cycles capable of generating reactive hydroxyl radicals. These have been implicated as diffusible oxidants responsible for cellulose depolymerization by brown rot fungi. Thus, enzyme diversity and the coexistence of brown and white rot fungi suggest complex interactions of fungal species and degradative strategies during the decay of lodgepole pine.IMPORTANCE The deconstruction of recalcitrant woody substrates is a central component of carbon cycling and forest health. Laboratory investigations have contributed substantially toward understanding the mechanisms employed by model wood decay fungi, but few studies have examined the physiological processes in natural environments. Herein, we identify the functional genes present in field samples of extensively decayed lodgepole pine (Pinus contorta), a major species distributed throughout the North American Rocky Mountains. The classified transcripts and proteins revealed a diverse array of oxidative and hydrolytic enzymes involved in the degradation of lignocellulose. The evidence also strongly supports simultaneous attack by fungal species employing different enzymatic strategies
Epigenetic and phenotypic changes result from a continuous pre and post natal dietary exposure to phytoestrogens in an experimental population of mice
Background: Developmental effects of exposure to endocrine disruptors can influence adult
characters in mammals, but could also have evolutionary consequences. The aim of this study was
to simulate an environmental exposure of an experimental population of mice to high amounts of
nutritional phytoestrogens and to evaluate parameters of relevance for evolutionary change in the
offspring. The effect of a continuous pre- and post-natal exposure to high levels of dietary
isoflavones was evaluated on sexual maturity, morphometric parameters and DNA methylation
status in mice. Adult mice male/female couples were fed ad libitum either with control diet
(standard laboratory chow) or ISF diet (control diet plus a soy isoflavone extract at 2% (w/w) that
contained the phytoestrogens genistein and daidzein). In the offspring we measured: i) the onset of
vaginal opening (sexual maturation) in females, ii) weight and size in all pups at 7, 14, 21 and 42 days
post-natal (dpn) and iii) DNA methylation patterns in skeletal α-actin (Acta1), estrogen receptor-
α and c-fos in adults (42 dpn).
Results: Vaginal opening was advanced in female pups in the ISF group, from 31.6 ± 0.75 dpn to
25.7 ± 0.48. No differences in size or weight at ages 7, 14 or 21 dpn were detected between
experimental groups. Nevertheless, at age 42 dpn reduced size and weight were observed in ISF
pups, in addition to suppression of normal gender differences in weight seen in the control group
(males heavier that females). Also, natural differences seen in DNA methylation at Acta1 promoter
in the offspring originated in the control group were suppressed in the ISF group. Acta1 is known
to be developmentally regulated and related to morphomotric features.
Conclusion: This study demonstrates in mammals that individuals from a population subjected to
a high consumption of isoflavones can show alterations in characters that may be of importance
from an evolutionary perspective, such as epigenetic and morphometric characters or sexual
maturation, a life history character.We greatly appreciate the linguistic revision of the manuscript by Renée
Hill and critical review of the manuscript by Dr. Anders Lindroth. We are
very thankful for funding by FONDECYT projects 1010647 to PS and
1030309 to LV, CONICYT fellowship for graduate studies and MECESUP
grant for overseas training to CG, and NH&MRC project grant funding to
SJC
RESPONS PRODUKSI AGROINDUSTRI SE’I BABI TERHADAP PERMINTAAN KONSUMEN (STUDI KASUS PADA USAHA AGROINDUSTRI SE’I BABI BAUN)
A case study focused on the agroindustry of Baun smoked pork in the District of Amarasi Barat Regency of Kupang has been conducted from September to October 2016. The aims of the study were: (1) to assess consumer perceptions about the peculiarities of Baun smoked pork; (2) to identify the efforts made by the producer in maintaining the customers; (3) to analyze factors that influence consumer demand, and (4) to analyze the extent of the production response to the demand of smoked pork. Ninety consumer respondents were included in this study following a simple random sampling procedure during 30 days of interviewed (3 respondents/day). The data obtained were descriptively analyzed for both qualitative and quantitative. Cobb-Douglas function was used to analyse the correlation and regression for quantitative data. The results showed that Baun smoked pork had a distinctive taste, with simple way of serving and on time. It also had available lesehan dining facilities. Factors that have a significant effect on the demand of smoked pork were the income and the number of family member. Furthermore, the production of smoked pork is influenced by consumer’s demand and day of production. The smoked pork production did not corresponding with the consumer demand, where the total demand of 2,624 kg per month. Therefore, producers should have the right strategy to maintain their potential consumers through the efforts of increasing the number of pig slaughtered especially at the week end.
ABSTRAK
Penelitian bertujuan untuk: (1) mengetahui persepsi konsumen tentang kekhasan produk se’i babi Baun; (2) mengidentifikasi upaya produsen dalam mempertahankan pelanggan; (3) menganalisis faktor yang mempengaruhi permintaan konsumen; (4) menganalisis sejauh mana respons produksi terhadap permintaan se’i babi. Pengambilan contoh konsumen sebanyak 90 orang dilakukan secara acak sederhana dengan teknik pengambilan tiga orang per hari selama 30 hari. Data dianalisis secara deskriptif kualitatif dan kuantitatif. Analisis kuantitatif berupa analisis korelasi dan regresi dengan pendekatan fungsi Cobb-Douglas. Hasil penelitian menunjukkan bahwa se’i babi Baun memiliki rasa yang khas, cara penyajiannya sederhana dan tepat waktu serta tersedia fasilitas makan lesehan. Faktor-faktor yang berpengaruh nyata terhadap jumlah permintaan se’i babi Baun yaitu pendapatan dan jumlah anggota keluarga. Selanjutnya, produksi se’i babi Baun dipengaruhi oleh permintaan konsumen dan hari produksi. Produksi belum merespon permintaan konsumen dimana jumlah permintaan sebanyak 2.624 kg per bulan belum dapat dipenuhi oleh produsen se’i babi. Oleh karena itu, produsen harus memiliki strategi yang tepat untuk mempertahankan konsumen potensialnya melalui upaya meningkatkan jumlah ternak babi yang dipotong khususnya pada akhir minggu
Carers’ responses to shifting identity in dementia in Iris and Away From Her: cultivating stability or embracing change?
An emphasis on supporting and maintaining self-identity in people who have dementia for as long as possible has gone hand in hand with the revitalisation of dementia interventions, services and empowerment. However, recognition of the need for change, adaptation and personal growth is as necessary when living with dementia as at any other time in people's lives. Those who care for people with dementia must constantly navigate this tension between continuity and change within the context of memory loss, knowing when to respond by reinforcing the ‘self’ they have known over time, and when it may be better to respond by acknowledging the changes that have taken place in that ‘self’. The creative arts are avenues for the exploration of the caring relationship under these conditions, conveying the challenges and stimulating audiences to ask how they themselves might choose to respond in a similar situation. This article considers how the scenarios of two noted films, Iris (dir. Richard Eyre, 2001 UK)) and Away From Her (dir. Sarah Polley, 2006 Can), present the dilemmas of identity and caring. In both, a husband cares for a wife experiencing cognitive decline, but responds differently in each to her shifting needs and experience of identity. We argue that the two films reveal complementary and provocative perspectives on this situation. They offer no easy answers, but provide insights into the everyday decisions characteristic of caring for someone who has dementia
Overview of molecular typing methods for outbreak detection and epidemiological surveillance
Typing methods for discriminating different bacterial isolates of the same species are essential epidemiological tools in infection prevention and control. Traditional typing systems based on phenotypes, such as serotype, biotype, phage-type, or antibiogram, have been used for many years. However, more recent methods that examine the relatedness of isolates at a molecular level have revolutionised our ability to differentiate among bacterial types and subtypes. Importantly, the development of molecular methods has provided new tools for enhanced surveillance and outbreak detection. This has resulted in better implementation of rational infection control programmes and efficient allocation of resources across Europe. The emergence of benchtop sequencers using next generation sequencing technology makes bacterial whole genome sequencing (WGS) feasible even in small research and clinical laboratories. WGS has already been used for the characterisation of bacterial isolates in several large outbreaks in Europe and, in the near future, is likely to replace currently used typing methodologies due to its ultimate resolution. However, WGS is still too laborious and time-consuming to obtain useful data in routine surveillance. Also, a largely unresolved question is how genome sequences must be examined for epidemiological characterisation. In the coming years, the lessons learnt from currently used molecular methods will allow us to condense the WGS data into epidemiologically useful information. On this basis, we have reviewed current and new molecular typing methods for outbreak detection and epidemiological surveillance of bacterial pathogens in clinical practice, aiming to give an overview of their specific advantages and disadvantages.</p
Overview of molecular typing methods for outbreak detection and epidemiological surveillance
Typing methods for discriminating different bacterial isolates of the same species are essential epidemiological tools in infection prevention and control. Traditional typing systems based on phenotypes, such as serotype, biotype, phage-type, or antibiogram, have been used for many years. However, more recent methods that examine the relatedness of isolates at a molecular level have revolutionised our ability to differentiate among bacterial types and subtypes. Importantly, the development of molecular methods has provided new tools for enhanced surveillance and outbreak detection. This has resulted in better implementation of rational infection control programmes and efficient allocation of resources across Europe. The emergence of benchtop sequencers using next generation sequencing technology makes bacterial whole genome sequencing (WGS) feasible even in small research and clinical laboratories. WGS has already been used for the characterisation of bacterial isolates in several large outbreaks in Europe and, in the near future, is likely to replace currently used typing methodologies due to its ultimate resolution. However, WGS is still too laborious and time-consuming to obtain useful data in routine surveillance. Also, a largely unresolved question is how genome sequences must be examined for epidemiological characterisation. In the coming years, the lessons learnt from currently used molecular methods will allow us to condense the WGS data into epidemiologically useful information. On this basis, we have reviewed current and new molecular typing methods for outbreak detection and epidemiological surveillance of bacterial pathogens in clinical practice, aiming to give an overview of their specific advantages and disadvantages.</p
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