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1.
Dawn Sanders 《Kew Bulletin》2010,65(4):677-680
Professor Stephen Hopper has suggested that ‘possibly the most significant future challenge facing plant conservation is the
achievement of a global shift in value systems towards acceptance of the old cultural wisdom that humans are part of, not
separate from, nature’. Here I examine this challenge for contemporary humanity experiencing increasingly divergent ‘lifeworlds’
and ask if it is possible to be ‘all netted together’, and achieve cultural consilience in the face of increasing plant extinction.
The first part of the article explores a hybrid approach to botanical education, where ‘border crossings’ between ‘Pokémon’
and plant-based inquiry might facilitate 21st century urban children to engage more intimately with the living world. The
second part highlights how botanic gardens can facilitate expressions of lost botanical knowledge carried through human migration
from rural to urban contexts. The article ends with a discussion intended to provoke interdisciplinary discourse between botanical
science and botanical education, contextualised within the wider literature that examines the role of botanic gardens. 相似文献
2.
Grote M 《Journal of biosciences》2011,36(4):563-570
Starting in the 1960s, the Indian chemist Krishna Bahadur, from the University of Allahabad, published on organic and inorganic
particles that he had synthesized and baptized ‘Jeewanu’, or ‘particle of life’. Bahadur conceived of the Jeewanu as a simple form of the living. These studies are presented in a historical perspective and positioned within mid-20th century
research on the origin of life, notably the so-called ‘coacervate theory’ of the Soviet biochemist Aleksandr I Oparin. The
concepts of life proposed by Bahadur, Oparin and others are discussed from a historical standpoint. 相似文献
3.
Mahin Khatami 《Cell biochemistry and biophysics》2009,55(2):55-79
Acute inflammation is a highly regulated defense mechanism of immune system possessing two well-balanced and biologically
opposing arms termed apoptosis (‘Yin’) and wound healing (‘Yang’) processes. Unresolved or chronic inflammation (oxidative
stress) is perhaps the loss of balance between ‘Yin’ and ‘Yang’ that would induce co-expression of exaggerated or ‘mismatched’
apoptotic and wound healing factors in the microenvironment of tissues (‘immune meltdown’). Unresolved inflammation could
initiate the genesis of many age-associated chronic illnesses such as autoimmune and neurodegenerative diseases or tumors/cancers.
In this perspective ‘birds’ eye’ view of major interrelated co-morbidity risk factors that participate in biological shifts
of growth-arresting (‘tumoricidal’) or growth-promoting (‘tumorigenic’) properties of immune cells and the genesis of chronic
inflammatory diseases and cancer will be discussed. Persistent inflammation is perhaps a common denominator in the genesis
of nearly all age-associated health problems or cancer. Future challenging opportunities for diagnosis, prevention, and/or
therapy of chronic illnesses will require an integrated understanding and identification of developmental phases of inflammation-induced
immune dysfunction and age-associated hormonal and physiological readjustments of organ systems. Designing suitable cohort
studies to establish the oxido-redox status of adults may prove to be an effective strategy in assessing individual’s health
toward developing personal medicine for healthy aging. 相似文献
4.
This article critically analyzes the arguments of the ‘generalized Darwinism’ recently proposed for the analysis of social-economical
systems. We argue that ‘generalized Darwinism’ is both restrictive and empty. It is restrictive because it excludes alternative
(non-selectionist) evolutionary mechanisms such as orthogenesis, saltationism and mutationism without any examination of their
suitability for modeling socio-economic processes and ignoring their important roles in the development of contemporary evolutionary
theory. It is empty, because it reduces Darwinism to an abstract triple-principle scheme (variation, selection and inheritance)
thus ignoring the actual structure of Darwinism as a complex and dynamic theoretical structure inseparable from a very detailed
system of theoretical constraints. Arguing against ‘generalised Darwinism’ we present our vision of the history of evolutionary
biology with the help of the ‘hourglass model’ reflecting the internal dynamic of competing theories of evolution. 相似文献
5.
In a well-known collection of his essays in cognitive psychology Miller (The Psychology of Communication. Penguin, 1974) describes in detail a number of experiments aiming at a determination of the limits (if any) of the human
brain in processing information. He concludes that the ‘channel capacity’ of human subjects does not exceed a few bits or
that the number of categories of (one-dimensional) stimuli from which unambiguous judgment can be made are of the order of
‘seven plus or minus two’. This ‘magic number’ holds also, Miller found, for the number of random digits a person can correctly
recall on a row and also the number of sentences that can be inserted inside a sentence in a natural language and still be
read through without confusion.
In this paper we propose a dynamical model of information processing by a self-organizing system which is based on the possible
use of strange attractors as cognitive devices. It comes as an amusing surprise to find that such a model can, among other
things, reproduce the ‘magic number seven plus-minus two’ and also its variance in a number of cases and provide a theoretical
justification for them. This justification is based on the optimum length of a code which maximizes the dynamic storing capacity
for the strings of digits constituting the set of external stimuli.
This provides a mechanism for the fact that the ‘human channel’, which is so narrow and so noisy (of the order of just a few
bits per second or a few bits per category) possesses the ability of squeezing or ‘compressing’ practically an unlimited number
of bits per symbol—thereby giving rise to a phenomenal memory. 相似文献
6.
According to the approach developed by Thomas A. Sebeok (1921–2001) and his ‘global semiotics,’ semiosis and life converge.
This leads to his cardinal axiom: ‘semiosis is the criterial attribute of life.’ His global approach to sign life presupposes
his critique of anthropocentrism and glottocentrism. Global semiotics is open to zoosemiotics, indeed, even more broadly,
biosemiotics which extends its gaze to semiosis in the whole living universe to include the realms of macro- and microorganisms.
In Sebeok’s conception, the sign science is not only the study of communication in culture, but of communicative behaviour
from a biosemiotic perspective. 相似文献
7.
Andrew Turner 《Biology & philosophy》2012,27(3):419-432
Robin Nunn has argued that we should stop using the terms ‘placebo’ and ‘placebo effect’. I argue in support of Nunn’s position
by considering the logic of why we perform placebo comparisons. Like all comparisons, placebo comparison is just a case of
comparing one thing with another, but it is a mistake, I argue, to think of placebo comparison as a case where something is
compared to ‘a placebo’. Rather, placebo comparison should be understood as a situation which sets-up the treatment and control
groups in a particular way; not as a case involving objects or procedures called ‘placebos’ employed in order to control for
‘placebo effects’. 相似文献
8.
Wendy Wheeler 《Biosemiotics》2010,3(3):277-287
This article argues that organisms, defined by a semi-permeable membrane or skin separating organism from environment, are
(must be) semiotically alert responders to environments (both Innenwelt and Umwelt). As organisms and environments complexify over time, so, necessarily, does semiotic responsiveness, or ‘semiotic freedom’.
In complex environments, semiotic responsiveness necessitates increasing plasticity of discernment, or discrimination. Such
judgements, in other words, involve interpretations. The latter, in effect, consist of translations of a range of sign relations
which, like metaphor, are based on transfers (carryings over) of meanings or expressions from one semiotic ‘site’ to another.
The article argues that what humans describe as ‘metaphor’ (and believe is something which only pertains to human speech and
mind and, in essence, is ‘not real’) is, in fact, fundamental to all semiotic and biosemiotic sign processes in all living
things. The article first argues that metaphor and mind are immanent in all life, and are evolutionary, and, thus, that animals
certainly do have minds. Following Heidegger and then Agamben, the article continues by asking about the place of animal mind
in humans, and concludes that, as a kind of ‘night science’, ‘humananimal’ mind is central to the semiotics of Peircean abduction. 相似文献
9.
Ying Li Yuping Song Gongjun Shi Jianjun Wang Xilin Hou 《Acta Physiologiae Plantarum》2009,31(1):155-162
Changes in ascorbic acid content and antioxidant enzyme activities were investigated in non-heading Chinese cabbage (Brassica campestris ssp. chinensis Makino) leaves of ‘Wutacai’ and ‘Erqing’ exposed to excess copper (Cu). Cu treatment reduced the fresh weight of shoot and
root by 57% and 46% in ‘Wutacai’, and 60 and 54% in ‘Erqing’, respectively. The accumulation of copper in leaves was higher
in ‘Wutacai’ than that in ‘Erqing’. Compared to the control, ascorbic acid (AsA) contents were significantly decreased after
copper treatment in both cultivars, while they were higher in ‘Wutacai’ than in ‘Erqing’, which may explain the higher copper-tolerance
of ‘Wutacai’ with higher copper accumulation. The higher AsA contents of ‘Wutacai’ resulted from their lower activities of
degrading enzymes, such as ascorbate oxydase (AAO) and ascorbate peroxidase (APX), as well as the increasing activity of dehydroascorbate
reductase (DHAR) after copper treatment compared with ‘Erqing’. Copper stimulated superoxide dismutase (SOD) activity in both
cultivars, but for catalase (CAT), there was little difference between both cultivars. Peroxidases (POD) activity was decreased
after copper treatment in ‘Erqing’, while in ‘Wutacai’, it was significantly increased at 14 days, and POD activity was higher
in ‘Wutacai’ than that in ‘Erqing’ at 21 and 28 days. Therefore, the induced increasing activity of POD in ‘Wutacai’ also
played an important role in its copper tolerance. 相似文献
10.
Many interactive human skills are based on real-time error detection and correction. Here we investigate the spectral properties
of such skills, focusing on a synchronization task. A simple autoregressive error correction model, based on separate ‘motor’
and ‘cognitive’ sources, provides an excellent fit to experimental spectral data. The model can also apply to recurrent processes
not based on error correction, allowing commentary on previous claims of 1/ f-type noise in human cognition. A comparison of expert and non-expert subjects suggests that performance skill is not only
based on reduced variance and bias, but also on the construction of richer mental models of error correction.
Received: 4 October 1995 / Accepted in revised form: 25 February 1997 相似文献
11.
Shahram Rafieian 《Biosemiotics》2012,5(1):83-93
A human being is the simultaneous composite of several different levels of being, from atomic and subatomic to the level of
complex social interaction, and these levels are nested within the individual hierarchically (lower levels giving rise to
higher levels, etc.). One of the most important and influential approaches developed in the history of science has been that
of systems theory and systemic thinking, in which the different levels of the hierarchy, and the interactions between those
levels, are considered simultaneously. Although this model provides a comprehensive view of biological being, the transition
from one level to the other is not well defined in it. Uexküll and Pauli (Advances: Journal of the Institute for 417 the Advancement
of Health 3:158–174, 1986) suggested that semiosis is the translator of the events from one level to the other. From a psychological point of view, a myriad of semiotic events
happen inside an individual, and it has been suggested that among other semiotic events, inner speech plays an important role in mediating personal agency. Dialogical theories of the self, Jungian psychology and hypnosis research evidence show that there is a semiotic multiplicity
in human agency and consciousness, and that these multiple streams are all converge to a central semiotic singularity. I argue
in this paper that by taking a biosemiotic point of view, human ‘agency’ may be defined as the ability of an individual to
direct the incoming and internal streams of semioses and the ability to create an integrative and superordinate new stream
of semiosis in addition to the upwardly and downwardly component ones, and how such a view might open a new door for research
into the concept of human ‘personality’ and ‘agency’. 相似文献
12.
Previous research has shown that the qualities of nuptial gifts among nonhumans and marriage-related property transfers in
human societies such as bridewealth and dowry covary with aspects of mate quality. This article explores this issue for another
type of marriage-related property transfer: engagement rings. We obtained data on engagement ring costs and other variables
through a mail survey sent to recently married individuals living in the American Midwest. This article focuses on survey
responses regarding rings that were purchased by men acting alone and using only their own funds who then presented the rings
while making surprise proposals of marriage (n = 127). Men marrying younger women spent more on rings, as did men who earned more money and whose fiancées earned more money.
These findings suggest that the amounts spent on engagement rings, like bridewealth and dowry payments in other societies,
reflect aspects of both male and female mate quality. 相似文献
13.
Aleksandra Korzeniewska Katarzyna Niemirowicz-Szczytt 《Acta Physiologiae Plantarum》2000,22(3):235-238
Earliness is a crucial factor of tomato field production in Poland. A. Michalska and B. Kubicki (1978) conducted the first
investigations on tomato earliness at the Department of Plant Genetics and Breeding. The main conclusions from these studies
indicated that it was possible to obtain varieties earlier than ‘New Yorker’ as a result of transgression. The two new varieties
(‘Alfa’ and ‘Akord F1’) proved to be two weeks earlier than ‘New Yorker’. However, earliness was correlated with smaller fruit weight (30–40 g).
At the next stage of experiment some improvement was achieved both in the size of fruit (45 g for ‘Beta’ up to 70 g for ‘Alka’)
as well as colour intensity and good flavour. With the next few years fruit weight was still increased (up to 100 g for ‘Maskarena’)
and a higher level of firmness was obtained (mid firm fruits for ‘Maskarena’ and ‘Delta’). At present, the Polish Research
Centre for Cultivar Testing recommends our varieties ‘Betalux’, ‘Promyk’ and ‘Delta’ as standards. 相似文献
14.
Most temperate-zone birds live in environments with a regular seasonality, and primarily use the long-term changes in photoperiod
as a cue to initiate gonadal development in anticipation of the breeding season. Short-term cues such as food and temperature
are later used to fine-tune the rate of gonadal development to local conditions. Many tropical habitats are seasonal, but
the timing of the seasons (e.g., rainy season) can vary considerably between years. We hypothesize that to time breeding in
environments with seasonal variability, tropical birds respond to both long-term and short-term environmental cues to initiate
gonadal growth. We tested the effectiveness of photoperiod and food cues for the initiation of gonad growth in captive male
spotted antbirds (Hylophylax n. naevioides) from Panama. A ‘control’ group was maintained on the short natural photoperiod of 12 h light and 12 h dark (LD 12:12) and
adequate food. A ‘food-stimulated’ group was also held on LD 12:12 but received an increase in food quantity and quality.
A ‘photo+food-stimulated’ group experienced an increase in daylength by 1 h (LD 13:11, the maximal photoperiod in Panama)
and an increase in food quantity and quality. Within 3 weeks testis sizes of ‘food-stimulated’ birds increased significantly,
suggesting that food cues alone can initiate gonad development. As expected from the previous experiment, testis sizes of
‘photo+food-stimulated’ birds, but not ‘control’ birds, also increased. We suggest that the capability to respond to both
food and photoperiodic cues allows animal the flexibility to adjust reproductive activity to variable environmental conditions
each year. Future work should elucidate whether food provides nutritional or non-nutritional cues, and the neurophysiological
mechanisms by which food stimulates reproductive activity. 相似文献
15.
Linda M. Gustafsson Pål Börjesson 《The International Journal of Life Cycle Assessment》2007,12(3):151-159
Background, Aims and Scope Using renewable feedstock and introducing biocatalysts in the chemical industry have been suggested as the key strategies
to reduce the environmental impact of chemicals. The Swedish interdisciplinary programme ‘Greenchem’, is aiming to develop
these strategies. One target group of chemicals for Greenchem are wax esters which can be used in wood surface coatings for
wood furniture, etc. The aim of this study was to conduct a life cycle assessment of four different wood surface coatings,
two wax-based coatings and two lacquers using ultra violet light for hardening (UV lacquers). One of the two wax-based coatings
is based on a renewable wax ester produced with biocatalysts from rapeseed oil, denoted ‘green wax’, while the other is based
on fossil feedstock and is denoted ‘fossil wax’. The two UV lacquers consist of one ‘100% UV’ coating and one ‘water-based
UV’ coating. The scope was to compare the environmental performance of the new ‘green’ coating with the three coatings which
are on the market today.
Methods The study has a cradle-to-grave perspective and the functional unit is ‘decoration and protection of 1 m2 wood table surface for 20 years’. Extensive data collection and calculations have been performed for the two wax-based coatings,
whereas mainly existing LCI data have been used to characterise the production of the two UV lacquers.
Results For all impact categories studied, the ‘100% UV’ lacquer is the most environmentally benign alternative. The ‘water-based
UV’ is the second best alternative for all impact categories except EP, where the ‘fossil wax’ is slightly better. For GWP
the ‘fossil wax’ has the highest contribution followed by the ‘green wax’. For AP and EP it is the ‘green wax’ that makes
the highest environmental impact due to the contribution from the cultivation of the rapeseed and the production of the rapeseed
oil. For POCP the ‘fossil wax’ makes the highest contribution, slightly higher than the contribution from the ‘green wax’.
Also the energy requirements for the ‘100% UV’ lacquer is much lower than for the other coatings. The results from the toxicological
evaluation conducted in this study, which was restricted to include only the UV lacquers, are inconclusive, giving different
results depending on the model chosen, EDIP97 or USES.
Discussion The result in this study shows that the environmental benefits of using revewable feedstock and processes based on biocatalysis
in the production of wax esters used in wood surface coatings are rather limited. This is due to the high environmental impact
from other steps in the life cycle of the coating.
Conclusions Overall the ‘100% UV’ lacquer seems to be the best alternative from an environmental point of view. This study shows that
the hot spots of the life cycle of the coatings are the production of the ingredients, but also the application and drying
of the coatings. The toxicity assessment shows the need for the development of a new model, a model which finds common ground
in order to overcome the current situation of diverging results of toxicity assessments. The results in this study also point
to the importance of investigating the environmental performance of a product based on fossil or renewable feedstock from
a life cycle perspective.
Recommendations and Perspectives The results in this study show that an efficient way to improve the wood coating industry environmentally is to increase the
utilization of UV lacquers that are 100% UV-based. These coatings can also be even further improved by introducing biocatalytic
processes and producing epoxides and diacrylates from renewable raw material instead of the fossil-based ones produced with
conventional chemical methods in use today. In doing this, however, choosing a vegetable oil with good environmental performance
is important. An alternative application of the ‘green wax’ analysed in this study may be as an ingredient in health care
products, for example, which may result in greater environmental benefits than when the wax is used inwood coating products.
The results in this study illustrate the importance of investigating the environmental performance of a product from cradle-to-grave
perspective and not consider it ‘green’ because it is based on renewable resources. 相似文献
16.
The effects of indole-butyric acid (IBA) and electro-pulses on rooting and shoot growth were studied in vitro, using olive
shoot cultures. Tested shoots were obtained from seedlings belonging to three Spanish cultivars, ‘Arbequina’, ‘Manzanilla
de Sevilla’ and ‘Gordal Sevillana’, which have easy-, medium- and difficult-to-root rooting abilities, respectively. The standard
two-step rooting method (SRM), consisting of root induction in olive rooting medium supplemented with 0, 0.1 or 1 mg/l IBA
followed by root elongation in the same rooting medium without IBA, was compared with a novel one-step method consisting of
shoot electro-pulses of 250, 1,250 or 2,500 V in a solution of IBA (0, 0.1 or 1 mg/l) and direct transferral to root elongation
medium. The rooting percentage of the seedling-derived shoots obtained with the SRM was 76% for ‘Arbequina’ and ‘Gordal Sevillana’
cultivars and 100% for ‘Manzanilla de Sevilla’ cultivar, whereas with the electro-pulse method, the rooting percentages were
68, 64 and 88%, respectively. IBA dipping without pulse produced 0% rooting in ‘Arbequina’ seedling-derived shoots. The electroporation
in IBA not only had an effect on shoot rooting but also on shoot growth and development, with longer shoots and higher axillary
shoot sprouting and growth after some of the treatments. These effects were cultivar-dependent. The electro-pulse per se could
explain some of these effects on shoot development.
I.M.G. Padilla and I. Vidoy contributed equally to this article. 相似文献
17.
Eloisa Berman Arévalo Mirjam A. F. Ros-Tonen 《Human ecology: an interdisciplinary journal》2009,37(6):733-747
While much research on forest partnerships hitherto has been focused mainly on the drivers behind their formation, the kind
of actors and deals involved, and the factors that promote or hinder their success, much less attention has been paid to the
dynamic relationships and processes inherent in these partnerships. Based on the study of a partnership process in an indigenous
reservation in Colombian Amazonia covering a variety of projects, this paper seeks to fill part of this lacuna by analyzing
the partnership as a dynamic ‘discursive battlefield,’ in which objectives and actions are being constantly negotiated. Actors
in the Matavén partnership strategically incorporate discursive elements in order to pursue their own interests while also
endorsing those that ensure the continuation of collaboration. We conclude that discourses are embedded in partnership micro-politics.
On the one hand, discursive shifts occur as a reflection of power balances at given moments. On the other hand, discourses
constitute indispensable resources with the potential to both enhance individual actor’s negotiating power and to create opportunities
for compromise. Within an ongoing discursive tension between ‘conservation’ and ‘indigenous autonomy,’ flexible notions such
as ‘territorial ordering’ prove to be successful in allowing space for manoeuvre and granting conceptual coherence to shifts
occurring ‘on the ground.’ 相似文献
18.
Marc Ereshefsky 《Biology & philosophy》2010,25(4):553-568
This paper examines the species problem in microbiology and its implications for the species problem more generally. Given
the different meanings of ‘species’ in microbiology, the use of ‘species’ in biology is more multifarious and problematic
than commonly recognized. So much so, that recent work in microbial systematics casts doubt on the existence of a prokaryote
species category in nature. It also casts doubt on the existence of a general species category for all of life (one that includes
both prokaryotes and eukaryotes). Prokaryote biology also undermines recent attempts to save the species category, such as
the suggestion that species are metapopulation lineages and the idea that ‘species’ is a family resemblance concept. 相似文献
19.
Ernst W 《Culture, medicine and psychiatry》2011,35(4):536-545
This article explores the development of psychiatric institutions within the context of British colonial rule in India, in
particular during the late nineteenth and early twentieth centuries. Existing scholarship on ‘colonial medicine’ has tended
to focus on colonial power and hegemony and the British endeavour to ‘colonize the Indian body’ during the nineteenth century.
It is suggested here that reference to ‘colonial’ medicine and psychiatry tends to reify the ideology of colonialism and neglect
other important dimensions such as the role of international scientific networks and the mental hospital as the locus of care
and medicalization. From the later period of British colonial engagement in south Asia, people’s right and entitlement to
medical care and the colonial state’s obligation to provide institutional treatment facilities received increased attention.
As the early twentieth-century case of an Indian hospital superintendent shows, practitioners’ professional ambitions went
beyond the confines of ‘colonial psychiatry’. He practiced in his institution science-based psychiatry, drawing on models
and treatment paradigms that were then prevalent in a variety of countries around the globe. 相似文献
20.
Martin Maiden 《Morphology》2009,19(1):59-86
This study examines some cases of heteroclisis in the history of Romanian dialects, and concludes that the data call for a
reconsideration of Stump’s distinction (Language 82:279–322, 2006) between ‘cloven’ heteroclisis, where the intraparadigmatic
‘split’ is aligned with some morphosyntactic feature distinction, and ‘fractured’ heteroclisis, where this is not the case
and the pattern of heteroclisis is purely morphological. Stump’s account creates the impression that the ‘cloven’ variety
is universally predominant, and that the ‘fractured’ variety tends to follow very closely the available ‘cloven’ patterns
of the language. I shall suggest, instead, that the ‘fractured-only’ situation may in fact underlie heteroclisis cross-linguistically,
the phenomenon being in general sensitive not directly to morphosyntactic content, but rather to characteristic, and often
purely ‘morphomic’, patterns of stem-allomorphy.
Research for this paper was undertaken as part of the Arts and Humantities Research Council-funded project Autonomous Morphology in Diachrony: comparative evidence from the Romance Languages, currently being conducted at Oxford University. 相似文献