967 research outputs found
The persistence of populations facing climate shifts and harvest
No full textMany species are expected to shift their geographic distribution as climates change, and yet climate change is only one of a suite of stressors that species face. Species that might, in theory, be able to shift rapidly enough to keep up with climate velocity (the rate and direction that isotherms move across the landscape) may not in actuality be able to do so when facing the cumulative impacts of multiple stressors. Despite empirical reports of substantial interactions between climate change and other stressors, we often lack a mechanistic understanding of these interactions. Here, we developed and analyzed a spatial population dynamics model to explore the cumulative impacts of climate with another dominant stressor in the ocean and on land: harvest. We found that critical rates of climate velocity and harvest depend on the growth rate and dispersal kernel of the population, as well as the magnitude of the other stressor. This allowed us to identify conditions under which harvesting and climate velocity can together drive populations extinct even when neither stressor would do so in isolation. Except in these extreme cases, we also found that the interaction between the declines in biomass caused by climate velocity and harvest is approximately additive. Finally, we have shown that threshold harvest rules can be effective management tools to mitigate the interaction between the two stressors, while protected areas can either help or hinder,depending on how harvesters reallocate their effort. We also have parameterized the model for black rockfish (Sebastes melanops) to demonstrate the model’s broad applicability.Received 22 December 2014; revised 25 February 2015; accepted 4 March 2015; final version received 8 May 2015; published 23 September 2015.Peer reviewe
Ritorno a Thornfield. La "storia segreta" di Adèle Varens in Thornfield Hall di Emma Tennant
No full textIn the line of the Neo-Victorian movement within postmodern literature, in 2002 British author Emma Tennant (1937-2017) re-wrote Charlotte Brontë’s 1847 Jane Eyre as Thornfield Hall. Even though its subtitle, The Hidden Story of Jane Eyre, anticipates a new appendix to Jane’s widely known adventures, the novel is in fact centred on Adèle Varens, “the French dancer’s bastard”. In particular, Tennant’s narrative looks back at the Brontean novel by exploring the Parisian milieu in which the young Adèle breathes the air of the Révolution and learns how to resist the patriarchal and political established order; and yet, later on, she seems to forget the teachings she drew from Céline Varens, her mother, and her world in a problematic intertextual twist that questions the presence of the Other – once again represented by Bertha Antoinette Mason, echoing Jean Rhys’s 1966 masterpiece Wide Sargasso Sea – but ultimately/inevitably pays homage to Brontë’s classic
Women and independence in the nineteenth century novel : a study of Austen, Trollope and James
No full text'Women
and
independence in the nineteenth century novel : a
study
of
Austen, Trollope
and
James', begins
with the
concept of
independence
and works through the three
most common usages of
the
word.
The first, financial independence (not
needing to
earn one's
livelihood)
appears to be
a necessary prerequisite
for the
second
and third forms
of
independence,
although it is by
no means an
unequivocal good
in
any of
the
novels.
The
second,
intellectual
independence (not
depending
on others
for
one's opinion or conduct;
unwilling
to be
under obligation
to
others),
is
a matter of asserting independence
while employing
terms
which society recognizes.
The third,
of
being independent, is
exemplified
by
an
inward
struggle
for
a
knowledge
of self.
In
order
to trace the development
of
the idea
of self
during the
nineteenth century,
I have
chosen a group of novels which seem
to be
representative of
the beginning, the
middle, and the
end of
the period.
Particular
attention
is
given
to the
characterizations of
Emma
Woodhouse, Glencora Palliser, Isabel Archer, Milly Theale and
Maggie
Verver. Whereas in Jane Austen's
novels
the self
has a
definite shape
which the heroine
must
discover, and
in Anthony Trollope's
novels
the
self
(reflecting
the idea
of socially-determined man) must
learn to
accommodate social and political changes,
in Henry James's
novels
the
self
determined by
external manifestations
(hollow
man)
is
posed
against
the exercise of
the free
spirit or soul.
Jane Austen's
novels
look backward,
as she reacts against
late
eighteenth century romanticism, and
forward,
with
the development
of
the heroine
who exemplifies
intellectual independence. Anthony
Trollope's
women characters are creatures of social and political
adaptation; although
they do
not
derive their
reason
for being
from
men,
they
must accommodate
themselves to
men's wishes.
And
Henry James looks backward,
wistfully, at
Austen's
solid, comforting,
innocent
self and
forward, despairingly, to the dark,
unknowable self
of
the twentieth
century
Handheld-Impedance-Measurement System with seven-decade capability and potentiostatic function
No full textThis paper describes design and test of a new impedance-measurement system for nonlinear devices that exhibits a seven-decade range and works down to a frequency of 0.01 Hz. The system is specifically designed for electrochemical measurements, but the proposed architecture can be employed in many other fields where flexible signal generation and analysis are required. The system employs an unconventional signal generator based on two pulsewidth modulation (PWM) oscillators and an autocalibration system that allows uncertainties of less than 3% to be obtained over a range of 1 kΩ to 100 GΩ. A synchronous demodulation processing allows the noise superimposed to the low-amplitude input signals to be made negligibl
Material movement in the near eastern epipalaeolithic: implications of the shell and stone beads of direkli cave, Turkey
No full textBaysal, Emma L. (Trakya author)Direkli Cave is an Epipalaeolithic site in the central Taurus mountain range in southeastern Turkey that was used by mobile hunter-gatherer communities. The assemblage of beads from the cave, made primarily from shell (marine and freshwater) and stone, shows new evidence both that bead materials were brought to the site from the shores of the Mediterranean and that the material culture of the site has relationships to the Levant, northern Mesopotamia, and inner Anatolia. This article questions how such a bead assemblage should be interpreted in the light of existing evidence for the Near Eastern and Anatolian Epipalaeolithic and what it adds to our understanding of the better known contemporary Natufian culture of the Levant. It considers the long-distance movement of materials, interregional material cultural influences, and the way the Epipalaeolithic period is conceptualized more broadly
Adaptation strategies of coastal fishing communities as species shift poleward
No full textIn this period of environmental change, understanding how resource users respond to such changes is critical for effective resource management and adaptation planning. Extensive work has focused on natural resource responses to environmental changes, but less has examined the re- sponse of resource users to such changes. We used an interdisciplinary approach to analyse changes in resource use among commercial trawl fish- ing communities in the northwest Atlantic, a region that has shown poleward shifts in harvested fish species. We found substantial community- level changes in fishing patterns since 1996: southern trawl fleets of larger vessels with low catch diversity fished up to 400 km further north, while trawl fleets of smaller vessels with low catch diversity shrank or disappeared from the data set over time. In contrast, trawl fleets (of both large and small vessels) with higher catch diversity neither changed fishing location dramatically or nor disappeared as often from the data set. This analysis suggests that catch diversity and high mobility may buffer fishing communities from effects of environmental change. Particularly in times of rapid and uncertain change, constructing diverse portfolios and allowing for fleet mobility may represent effective adaptation strategies.Peer reviewe
Calaveradas y erudición. Historias. Revista de la Dirección de Estudios Históricos. Num. 100 (2018) mayo-agosto
No full text1 Carta de Joaquín García Icazbalceta a José Fernando Ramírez, México, 22 de enero, 1850, en Libros y exilio. Epistolario de José Fernando Ramírez con Joaquín García Icazbalceta y otros corresponsales, 1838-1870, compilación y estudio introductorio de Emma Rivas Mata y Edgar O. Gutiérrez L., México, INAH, 2010 (Fuentes), pp. 132-136.Rodrigo Martínez Baracs y Emma Rivas Mata, Entre sabios. Joaquín García Icazbalceta y Henry Harrisse, epistolario, 1865-1878, edición bilingüe anotada, México, INAH, 2016, 404 pp
Surgery for weight loss in adults
No full textBackground: bariatric (weight loss) surgery for obesity is considered when other treatments have failed. The effects of the available bariatric procedures compared with medical management and with each other are uncertain. This is an update of a Cochrane review first published in 2003 and most recently updated in 2009.Objectives: to assess the effects of bariatric surgery for overweight and obesity, including the control of comorbidities.Search methods: studies were obtained from searches of numerous databases, supplemented with searches of reference lists and consultation with experts in obesity research. Date of last search was November 2013.Selection criteria: randomised controlled trials (RCTs) comparing surgical interventions with non-surgical management of obesity or overweight or comparing different surgical procedures.Data collection and analysis: data were extracted by one review author and checked by a second review author. Two review authors independently assessed risk of bias and evaluated overall study quality utilising the GRADE instrument.Main results: twenty-two trials with 1798 participants were included; sample sizes ranged from 15 to 250. Most studies followed participants for 12, 24 or 36 months; the longest follow-up was 10 years. The risk of bias across all domains of most trials was uncertain; just one was judged to have adequate allocation concealment.All seven RCTs comparing surgery with non-surgical interventions found benefits of surgery on measures of weight change at one to two years follow-up. Improvements for some aspects of health-related quality of life (QoL) (two RCTs) and diabetes (five RCTs) were also found. The overall quality of the evidence was moderate. Five studies reported data on mortality, no deaths occurred. Serious adverse events (SAEs) were reported in four studies and ranged from 0% to 37% in the surgery groups and 0% to 25% in the no surgery groups. Between 2% and 13% of participants required reoperations in the five studies that reported these data.Three RCTs found that laparoscopic Roux-en-Y gastric bypass (L)(RYGB) achieved significantly greater weight loss and body mass index (BMI) reduction up to five years after surgery compared with laparoscopic adjustable gastric banding (LAGB). Mean end-of-study BMI was lower following LRYGB compared with LAGB: mean difference (MD) -5.2 kg/m² (95% confidence interval (CI) -6.4 to -4.0; P < 0.00001; 265 participants; 3 trials; moderate quality evidence). Evidence for QoL and comorbidities was very low quality. The LRGYB procedure resulted in greater duration of hospitalisation in two RCTs (4/3.1 versus 2/1.5 days) and a greater number of late major complications (26.1% versus 11.6%) in one RCT. In one RCT the LAGB required high rates of reoperation for band removal (9 patients, 40.9%).Open RYGB, LRYGB and laparoscopic sleeve gastrectomy (LSG) led to losses of weight and/or BMI but there was no consistent picture as to which procedure was better or worse in the seven included trials. MD was -0.2 kg/m² (95% CI -1.8 to 1.3); 353 participants; 6 trials; low quality evidence) in favour of LRYGB. No statistically significant differences in QoL were found (one RCT). Six RCTs reported mortality; one death occurred following LRYGB. SAEs were reported by one RCT and were higher in the LRYGB group (4.5%) than the LSG group (0.9%). Reoperations ranged from 6.7% to 24% in the LRYGB group and 3.3% to 34% in the LSG group. Effects on comorbidities, complications and additional surgical procedures were neutral, except gastro-oesophageal reflux disease improved following LRYGB (one RCT). One RCT of people with a BMI 25 to 35 and type 2 diabetes found laparoscopic mini-gastric bypass resulted in greater weight loss and improvement of diabetes compared with LSG, and had similar levels of complications.Two RCTs found that biliopancreatic diversion with duodenal switch (BDDS) resulted in greater weight loss than RYGB in morbidly obese patients. End-of-study mean BMI loss was greater following BDDS: MD -7.3 kg/m² (95% CI -9.3 to -5.4); P < 0.00001; 107 participants; 2 trials; moderate quality evidence). QoL was similar on most domains. In one study between 82% to 100% of participants with diabetes had a HbA1c of less than 5% three years after surgery. Reoperations were higher in the BDDS group (16.1% to 27.6%) than the LRYGB group (4.3% to 8.3%). One death occurred in the BDDS group.One RCT comparing laparoscopic duodenojejunal bypass with sleeve gastrectomy versus LRYGB found BMI, excess weight loss, and rates of remission of diabetes and hypertension were similar at 12 months follow-up (very low quality evidence). QoL, SAEs and reoperation rates were not reported. No deaths occurred in either group.One RCT comparing laparoscopic isolated sleeve gastrectomy (LISG) versus LAGB found greater improvement in weight-loss outcomes following LISG at three years follow-up (very low quality evidence). QoL, mortality and SAEs were not reported. Reoperations occurred in 20% of the LAGB group and in 10% of the LISG group.One RCT (unpublished) comparing laparoscopic gastric imbrication with LSG found no statistically significant difference in weight loss between groups (very low quality evidence). QoL and comorbidities were not reported. No deaths occurred. Two participants in the gastric imbrication group required reoperation.Authors' conclusions: surgery results in greater improvement in weight loss outcomes and weight associated comorbidities compared with non-surgical interventions, regardless of the type of procedures used. When compared with each other, certain procedures resulted in greater weight loss and improvements in comorbidities than others. Outcomes were similar between RYGB and sleeve gastrectomy, and both of these procedures had better outcomes than adjustable gastric banding. For people with very high BMI, biliopancreatic diversion with duodenal switch resulted in greater weight loss than RYGB. Duodenojejunal bypass with sleeve gastrectomy and laparoscopic RYGB had similar outcomes, however this is based on one small trial. Isolated sleeve gastrectomy led to better weight-loss outcomes than adjustable gastric banding after three years follow-up. This was based on one trial only. Weight-related outcomes were similar between laparoscopic gastric imbrication and laparoscopic sleeve gastrectomy in one trial. Across all studies adverse event rates and reoperation rates were generally poorly reported. Most trials followed participants for only one or two years, therefore the long-term effects of surgery remain unclear
Shifting habitats expose fishing communities to risk under climate change
No full textClimate change is expected to have a profound impact on the distribution, abundance and diversity of marine species globally1,2. These ecological impacts of climate change will affect human communities dependent on fisheries for livelihoods and well-being3. While methods for assessing the vulnerability of species to climate change are rapidly developing4 and socio-ecological vulnerability assessments for fisheries are becoming available5, there has been less work devoted to understanding how impacts differ across fishing communities. We developed a linked socio-ecological approach to assess the exposure of fishing communities to risk from climate change, and present a case study of New England and Mid-Atlantic (USA) fishing communities. We found that the northern part of the study region was projected to gain suitable habitat and the southern part projected to lose suitable habitat for many species, but the exposure of fishing communities to risk was strongly dependent on both their spatial use of the ocean and their portfolio of species caught. A majority of fishing communities were projected to face declining future fishing opportunities unless they adapt, either through catching new species or fishing in new locations. By integrating climatic, ecological and socio-economic data at a scale relevant to fishing communities, this analysis identifies where strategies for adapting to the ecological impacts of climate change will be most needed.Peer reviewe
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