bluuebunny/crossref_metadata_2025 huggingface dataset:
A recently identified hypothalamic nucleus expressing estrogen receptor α
Authors: Mori Hiroko , Matsuda Ken-ichi , Pfaff Donald W. , Kawata Mitsuhiro
Published: August 2008

We report evidence for the existence of a unique nucleus in the rat hypothalamus. This nerve cell group is situated in the interstitial area between the arcuate nucleus and ventromedial nucleus of the hypothalamus, and is primarily oriented sagittally, in a spindle shape. This nucleus was a well defined structure in Nissl-stained sections because of its location in an otherwise cell-poor zone. This sagittalis nucleus of the hypothalamus (SGN) exhibits significant sex differences in its volume and cell numbers, as defined by Nissl staining and estrogen receptor (ER) α immunoreactivity (ir), being significantly larger in males than in females. Treatment of neonatal females with testosterone eliminated these sex differences. It is noteworthy that adult female rats have estrous cycle-related variations in the ERα-ir cell distribution, decreasing during the proestrus phase of the cycle. Pharmacological experiments demonstrated that the single injection of estradiol benzoate had a significant effect on the ERα-ir cell count, suggesting the hormonal responsiveness of SGN neurons. This unique hypothalamic nucleus with its morphological sex differences and hormonal responsiveness is embedded in a region important for the regulation of endocrine functions and sexual behaviors.
Gamete plasticity in a broadcast spawning marine invertebrate
Authors: Crean Angela J. , Marshall Dustin J.
Published: August 2008

Sperm competition has classically been thought to maintain anisogamy (large eggs and smaller sperm) because males are thought to maximize their chance of winning fertilizations by trading sperm size for number. More recently it has been recognized that sperm quality (e.g., size, velocity) can also influence sperm competition, although studies have yielded conflicting results. Because sex evolved in the sea, debate has continued over the role of sperm competition and sperm environment in determining both sperm and egg size in externally fertilizing broadcast spawners. Remarkably, however, there have been no direct tests of whether broadcast spawners change the traits of their gametes depending on the likelihood of sperm competition. We manipulated the density (and thus, sperm environment) of a broadcast spawning ascidian (Styela plicata) in the field and then determined whether the phenotype of eggs and sperm changed. We found that sperm from adults kept at high density were larger and more motile than sperm from low-density adults.In vitrofertilizations revealed that sperm from high-density adults also lived longer and induced less polyspermy. Adult density also affected egg traits: eggs from high-density adults were smaller targets for sperm overall but produced larger ovicells than eggs from low-density adults. This suggests that broadcast spawning mothers balance (potentially conflicting) pre- and postzygotic selection pressures on egg size. Overall, our results suggest that sperm competition does not represent a strong force maintaining anisogamy in broadcast spawners. Instead, sperm limitation seems to select for large eggs and smaller, more numerous sperm.
Giving is self-rewarding for monkeys
Authors: de Waal Frans B. M. , Leimgruber Kristin , Greenberg Amanda R.
Published: August 2008

Helping and sharing among humans is often motivated by empathy and accompanied by a sense of satisfaction. To determine whether similar self-rewarding mechanisms may underpin assistance among nonhuman primates, eight female brown capuchin monkeys (
Cebus apella
) underwent testing in a simple choice paradigm. Paired with a partner, subjects could select either a “selfish” option that rewarded only themselves, or a “prosocial” option that rewarded both of them. Subjects systematically favored the prosocial option provided their partner was a) familiar, b) visible, and c) receiving rewards of equal value. Prosocial tendencies increased with social closeness, being lowest toward strangers and highest toward kin. That the monkeys understood the options was suggested by greater orientation to the partner during prosocial than selfish choices. Prosocial preferences were reduced by inequity, when the partner received a superior reward. If the view between both monkeys was blocked, choices became strikingly selfish. Thus, under certain conditions, delivering benefits to others seems gratifying to nonhuman primates.
Retinal waves in mice lacking the β2 subunit of the nicotinic acetylcholine receptor
Authors: Sun Chao , Warland David K. , Ballesteros Jose M. , van der List Deborah , Chalupa Leo M.
Published: August 2008

The structural and functional properties of the visual system are disrupted in mutant animals lacking the β2 subunit of the nicotinic acetylcholine receptor. In particular, eye-specific retinogeniculate projections do not develop normally in these mutants. It is widely thought that the developing retinas of β2
−/−
mutants do not manifest correlated activity, leading to the notion that retinal waves play an instructional role in the formation of eye-specific retinogeniculate projections. By multielectrode array recordings, we show here that the β2
−/−
mutants have robust retinal waves during the formation of eye-specific projections. Unlike in WT animals, however, the mutant retinal waves are propagated by gap junctions rather than cholinergic circuitry. These results indicate that lack of retinal waves cannot account for the abnormalities that have been documented in the retinogeniculate pathway of the β2
−/−
mutants and suggest that other factors must contribute to the deficits in the visual system that have been noted in these animals.
The Treatment of ‘Nomen’ in the First Slovenian Grammar (Bohorič 1584)
Authors: Ahačič Kozma
Published: August 2008

The article focuses on the treatment of the noun (nomen) in the grammar published in 1584 by the first Slovenian grammarian, Adam Bohorič (c.1520–1598), under the title Arcticae horulae succisivae de Latinocarniolana literatura (“Spare winter hours on Latin-Carniolan grammar”). The chapter on the noun is examined in the larger context of European grammar-writing, revealing the Bohorič grammar to be a fully-fledged humanist text. In addition, the article explains certain aspects of the work which have sometimes been criticised as weaknesses, provides graphic representations of its structure, and describes Bohorič’s debt to Philipp Melanchthon (1497–1560), the similarities between his work and the German grammar by Johannes Clajus (1535–1592), and the parallels with other grammarians. Moreover, some new findings are presented concerning the glossaries accompanying the paradigms.
Narrative as snapshot
Authors: Hamilton Heidi E.
Published: August 2008

Sociolinguists and discursive psychologists interested in the construction of identity in discourse have focused their attention on how people recount their life events, arguing that narrative choices can reveal much about how narrators see themselves and how they wish to be seen by those listening to their stories. What happens, though, when severe memory loss interferes with this process? In this article, I examine the intersection of narrative, identity and memory by revisiting five (total of 2 hours and 39 minutes) tape-recorded conversations I had over 4½ years with a woman, Elsie, in her 80s at the moderately severe stage of Alzheimer’s disease (Hamilton, 1994). Focusing on a set of 204 clauses spoken by Elsie that contain past references within these conversations, I differentiate those clauses that are part of conversational narratives (56 or 27%) from independent clauses I term ‘narrative traces’ (148 or 73%). I then identify and examine in greater detail the linguistic construction of the storyworld within fifteen short narratives comprising the 56 narrative clauses. Special attention is given to nominal, verbal, spatial and temporal reference. I identify problems in orientation that have consequences for the coherence of the narrative as a text, as well as for the discursive construction of the narrator’s identity. I close with thoughts about how identity construction can be understood in the (near) absence of coherent reconstructions of the past. Possible useful approaches include Bakhtin’s (1981) notion of word “flavors,” Agha’s (2005) work on enregistered voices, and discourse strategies anchored in the interactional here-and-now, such as “small” talk and politeness work (Brown & Levinson, 1987).
Telling good stories in different languages
Authors: Minami Masahiko
Published: August 2008

There are many ways to tell a story, but whether a story is good or bad depends on whether or not the listener/reader can comprehend all that the speaker/writer wants to convey in his or her story. This study examines the characteristics of stories that native speakers of given languages consider to be good. Forty English-Japanese bilingual children ages six to twelve were asked to narrate a picture storybook in both English and Japanese. Also involved in the study were 16 adult native Japanese speakers and 16 adult native English speakers who evaluated the stories produced by the bilingual children. An analysis of narratives receiving high ratings from evaluators shows that most stories considered good in English or Japanese should be lengthy stories with a large and varied vocabulary, and should be told in the past tense. In addition to those similarities in effective stories told in the two languages, we also found dissimilarities between “good” stories in English and “good” stories in Japanese. English evaluators felt that relating a series of events in chronological order is only one part of a good story. Providing evaluative comments (i.e., statements or words that tell the listener/reader what the narrator thinks about a person, place, thing, or event) is an indispensable part of telling good stories. So, in stories in English, aside from the standard expectation of a sequential series of events, providing the listener with emotional information is considered equally important. On the other hand, Japanese speakers accepted stories that emphasize a temporal sequence of action with less emphasis on nonsequential information, especially evaluative descriptions, and which effectively use passive forms and subject-referencing markers to enable a clear chronological sequence of events. Because the standards of what makes a good story may differ in the home and school languages/cultures, and because of the complex nature of such differences as shown in this study, it seems advisable that schools intervene and support the development of bilingual children’s skills in the use of the mainstream culture’s standards.
“She discriminated against her own race”
Authors: Flannery Mércia Santana
Published: August 2008

Current studies within narrative analysis and sociolinguistics have shown that identities are emergent and negotiated in current talk and, thus, not pre-existing the now and then of a given interaction. This article presents the analysis of a story told by a black Brazilian woman describing an episode of racial discrimination between two black characters in which prejudice was transmitted through the voice of a white figure. While the storyteller articulates the multi-layered voicing in her story, she also portrays relationships and makes identity claims for herself while also drawing on, and sometimes contradicting, prevailing ideologies of race and racism in her culture. I analyze the linguistic means through which the narrator constructs different positioning levels (Bamberg, 1997) while the roles of author, figure and principal (Goffman, 1981) shift to represent the actions performed in the story world by its different characters. The narrator’s main strategies are the lamination of the characters’ speech through constructed dialogue and references to skin color, which enable her to interpret the episode of discrimination toward an individual of the same race.
Variation in storytelling style amongst New Zealand schoolchildren
Authors: Page Ruth
Published: August 2008

The relationship between emergent narrative skills, gender and ethnicity continues to be an important area of debate, with significant socio-political consequences. This paper explores the ways in which these variables intersect in a cross-cultural, longitudinal study of children’s storytelling, focusing on data taken from a multicultural school in Auckland, NZ. Differences in storytelling style reflected the characteristics of Maori English and Pakeha English conversational narratives, but also varied according to age and gender, where the variation was most marked for the 10-year-old children, and was most polarised between the narratives of the Pakeha girls and Maori boys. A longitudinal comparison indicated that these differences were by no means fixed, and that over time the older Maori boys’ storytelling altered in line with the literacy demands to conform to the dominant westernised pattern being imposed in this pedagogic context. This study thus points to the ongoing importance of analysing the shifting ways in which gender and cultural identity are renegotiated in educational contexts, suggesting that there is more scope for questioning and potentially changing dominant literacy practices in this part of New Zealand.
Diabetes mellitus and pelvic girdle syndrome in pregnancy – Is there an association?
Authors: EBERHARD‐GRAN MALIN , ESKILD ANNE
Published: September 2008

Objective. Increased levels of relaxin, a hormone structurally belonging to the insulin‐like growth factor family, has been associated with both pelvic girdle pain and type 1 diabetes in pregnancy. However, an association between pelvic girdle pain in pregnancy and diabetes has not been investigated. The aim of this study was to investigate whether or not an association exists between diabetes and pelvic girdle syndrome. Design. Cross‐sectional questionnaire study. Setting. All women 18–40 years old, in two municipalities in Norway during 1998–1999 were eligible for the study. Sample. A total of 1,816 women with at least one prior delivery constituted the study sample. Methods. Pelvic girdle syndrome during last pregnancy was the outcome variable, defined as pain in the anterior pelvis and bilateral posterior pelvis. The impact of diabetes on developing pelvic girdle syndrome was estimated as odds ratios in logistic regression analyses. Results. Diabetes increased the risk of pelvic girdle syndrome (adjusted odds ratio 7.3; 95% confidence interval: 1.8–28.5). In addition, age ≥25 years at delivery and obesity (body mass index ≥35) were associated with pelvic girdle syndrome. Parity and time since delivery were not significantly associated with pelvic girdle syndrome. Conclusions. The results in multivariate analyses indicate an association between pelvic girdle syndrome and diabetes. The causes of pelvic girdle pain are not known. However, our results encourage further exploration of hormonal factors.
Dilemmas of difference and the identification of special educational needs/disability: International perspectives
Authors: Norwich Brahm
Published: September 2008

This article reports findings from an international study about dilemmas of difference in relation to special educational needs and disability in education. It was part of a larger study of the perspectives of 132 education practitioners and policy makers in England, the USA and the Netherlands to a range of dilemmas of difference. It also compares these current perspectives with ones from similar groups in England and the USA from the early 1990s. Participants were interviewed about their perspectives on a presented dilemma about the consequences of identifying children as having a disability or a special educational need. The data are presented in quantitative terms (degrees of recognition and resolution of dilemma) and qualitative terms (reasons, justifications and suggested resolutions). The findings show variations in responses to the dilemma that relate to national differences, but also commonalities in the recognition of this dilemma, reasons for recognising and ways of resolving the dilemma.
The n-Cu0.9Ag0.1In3Se5chalcopyrite, electronic as well as ionic conductor
Authors: Díaz R
Published: August 2008

A resistance increase with time of the n-Cu0.9Ag0.1In3Se5chalcopyrite has been observed. This new effect is analysed in terms of a hypothesis of ion migration and Schottky barrier formation. These results might explain why different solar cell efficiencies are obtained for the chalcopyrites, CuInSe2and CuInxGa1−xSe2, when an In-rich film is deposited on top of the chalcopyrite. In these solar cells, ion migration can exist and a new effect appears similar to the one observed in our compound.

The ions, probably the cations, are moved by the electrical field towards the cathode. A gradient of mobile ions appears across the sample and the positive charge is accumulated near this electrode such that it varies the metal–semiconductor interface. This interface is a Schottky barrier where the contact potential is a function of time due to the arrival of ions.

The electrical measurements have been carried out on a solid state device, graphite/n-Cu0.9Ag0.1In3Se5/graphite. The current intensity and the potential drop across the sample have been measured with time when a constant electrical potential is applied for 600 s at dark or under ultraviolet illumination and at room temperature. A comparative study in similar electrical conditions is done; the current intensity difference and the potential drop across the difference (under ultraviolet illumination minus at dark) are not constant and both measurements increase with time.
Modelling of carbon migration during JET 13C injection experiments
Authors: Strachan J.D. , Likonen J. , Coad P. , Rubel M. , Widdowson A. , Airila M. , Andrew P. , Brezinsek S. , Corrigan G. , Esser H.G. , Jachmich S. , Kallenbach A. , Kirschner A. , Kreter A. , Matthews G.F. , Philipps V. , Pitts R.A. , Spence J. , Stamp M. , Wiesen S.
Published: August 2008

JET has performed two dedicated carbon migration experiments on the final run day of separate campaigns (2001 and 2004) using 13CH4 methane injected into repeated discharges. The EDGE2D/NIMBUS code modelled the carbon migration in both experiments. This paper describes this modelling and identifies a number of important migration pathways: (1) deposition and erosion near the injection location, (2) migration through the main chamber SOL, (3) migration through the private flux region (PFR) aided by
E
×
B
drifts and (4) neutral migration originating near the strike points. In H-Mode, type I ELMs are calculated to influence the migration by enhancing erosion during the ELM peak and increasing the long-range migration immediately following the ELM. The erosion/re-deposition cycle along the outer target leads to a multistep migration of 13C towards the separatrix which is called ‘walking’. This walking created carbon neutrals at the outer strike point and led to 13C deposition in the PFR. Although several migration pathways have been identified, quantitative analyses are hindered by experimental uncertainty in divertor leakage, and the lack of measurements at locations such as gaps and shadowed regions.
A linear mixed model with temporal covariance structures in modelling catch per unit effort of Baltic herring
Authors: Mikkonen S. , Rahikainen M. , Virtanen J. , Lehtonen R. , Kuikka S. , Ahvonen A.
Published: August 2008

Mikkonen, S., Rahikainen, M., Virtanen, J., Lehtonen, R., Kuikka, S., and Ahvonen, A. 2008. A linear mixed model with temporal covariance structures in modelling catch per unit effort of Baltic herring. – ICES Journal of Marine Science, 65: 1645–1654. Changes in the structure and attributes of a fleet over time will break down the proportionality of catch per unit effort (cpue) and stock biomass. Moreover, logbook data from commercial fisheries are hierarchical and autocorrelated. Such features not only complicate the analysis of cpue data but also seriously limit the application of a generalized linear model approach, which nevertheless is applied commonly. We demonstrate a linear mixed model application for a large hierarchical dataset containing autocorrelated observations. In the analysis, the key idea is to explore the properties of the error term of the model. We modified the residual covariance matrix, allowing the introduction of assumed fisher behaviour, influencing the catch rate. Fisher behaviour consists of accumulated knowledge and learning processes from their earlier area- and time-specific catch rates. Also, we investigated the effects of vessel-specific parameters by introducing random intercepts and slopes in the model. A model with the autoregressive moving average residual covariance matrix structure was superior over the block-diagonal and autoregressive (AR1) structure for the data, having a time-dependent correlation among trawl hauls. The results address the benefits of statistically advanced methods in obtaining precise and unbiased estimates from cpue data, to be used further in stock assessment. Fisheries agencies are encouraged to monitor the relevant vessel and gear attributes, including engine power and gear size, and the deployment practices of the gear.
Sterilization
Authors: Peet Danielle
Published: August 2008

Sterilization can be an empowering decision for the right person at the right time in their life. There are good alternatives, such as the intrauterine device, which provide better prevention of pregnancy without the risks associated with surgery. This article discusses the pros and cons of female and male sterilization and provides advice on how best to facilitate informed, patient-centred family planning.
Communication Theory Models—Outside the Face-To-Face Consultation
Authors: Thistlethwaite Jill
Published: August 2008

The fundamental interaction at the core of general practice is the consultation between patient and doctor. To achieve the optimal outcomes from such encounters for both parties, the general practitioner (GP) must be a good communicator. Moreover, the skilled GP needs to be able to facilitate patients to share their stories and to share in decision making with regards to management. The majority of communication skills training programmes focus on face-to-face patient—doctor communication but there are also skills for other interactions to be learnt, practised and developed. The process of communication is also varied—verbal and written, telephone and electronic, to one person and to groups, to lay people and to professional colleagues, to fluent English speakers and to speakers with English as a second language. This article reviews the process of communication outside the consultation room.
The Making of A Good Doctor: A Qualitative Assessment of the Views of a General Practice Manager
Authors: Metcalfe Neil H
Published: August 2008

‘One finger in the throat and one in the rectum’ produced a competent doctor in the 19th century but the ideal characteristics of modern doctors are not so easily defined. This topic is continually being mulled over in homes, waiting rooms, academic conferences, government think tanks and the nation's media, but determining what makes a good doctor is difficult. The General Medical Council's Good Medical Practice' lists 14 specific duties of a doctor ( Box 1 ) but in one survey, participants from 24 countries yielded 70 different responses about what makes a good doctor, ranging from the typical necessity for compassion and competence to the more unusual courage and creativity.
Acne Vulgaris
Authors: Alsop Rebecca
Published: August 2008

Acne vulgaris is a common inflammatory condition affecting the pilosebaceous unit. It affects most adolescents at some point and is most prevalent between the ages 13–18. It tends to improve for most sufferers by their mid-twenties. In a minority of people (3% of men and 12% of women), acne may persist well into adulthood.
Progestogen-Only Contraception
Authors: Nash Emma
Published: August 2008

Progestogen-only contraception refers to the methods of contraception that contain a synthetic form of progesterone. In 2005/2006, 10% of all women aged 16–49 in the UK were using progestogen-only contraception. Such contraceptive methods include the progestogen-only contraceptive pill, injectable forms, the subdermal implant and the Mirena intrauterine system (IUS). In addition, emergency contraception in the form of Levonelle 1500 is progestogen only.
The Laterality Index in the Evaluation of Distal Sensorimotor Neuropathy
Authors: Lo Yew-Long , Leoh Teng-Hee , Lim Li-Ling , Fook-Chong Stephanie , Ng Yueh-Ling , Ratnagopal Pavanni
Published: September 2008

Objective:

Electrodiagnostic evaluation of distal sensorimotor neuropathy can be technically challenging. Conventional nerve conduction studies (NCS) often include unilateral upper and lower limb evaluation for patients with suspected sensorimotor peripheral neuropathy. For patients with predominantly lower extremity complaints, NCS of both lower limbs are performed occasionally. Side-to-side NCS parameters have not been adequately addressed.

Methods:

We performed NCS prospectively on 132 patients presenting with complaints of bilateral numbness or weakness in the extremities and 45 normal controls. The laterality index (LI) was defined as ratio of the smaller to the larger amplitude in a sensory or motor NCS, as a novel side-to-side comparison parameter.

Results:

Ten patients had at least 1 sensory or motor NCS with LIs exceeding that of normal controls. Patients 1-7 (group 1) had diagnoses of autoimmune or neoplasia-related conditions and all had 3 or more NCS with abnormal LIs. In contrast, patients 8-10 (group 2) had diabetes mellitus and all had 2 or less NCS with abnormal LIs (unpaired t test; P = 0.002). In group 1, patients 1-4, 6, and 7 all had both upper and lower limb LI abnormalities. In contrast, only 1 patient (patient 9) had upper limb LI abnormality in group 2.

Conclusions:

Patients with abnormal LIs were uncommon in our cohort. Patients with diabetes mellitus had significantly less abnormal LIs than those with autoimmune or neoplasia-related etiologies. There is evidence of vasculitic inflammation documented in diabetic neuropathy. However, this process may be significantly less prominent compared with the former 2 conditions. Our findings of predominantly lower limb LI abnormalities suggest the presence of a length-dependent distal neuropathic process in diabetes mellitus. The LI is a simple and useful adjunct to detect asymmetrical NCS abnormalities. It may also provide helpful information regarding the underlying etiology.
Coping with carbon: a near-term strategy to limit carbon dioxide emissions from power stations
Authors: Breeze Paul
Published: August 2008

Burning coal to generate electricity is one of the key sources of atmospheric carbon dioxide emissions; so, targeting coal-fired power plants offers one of the easiest ways of reducing global carbon emissions. Given that the world's largest economies all rely heavily on coal for electricity production, eliminating coal combustion is not an option. Indeed, coal consumption is likely to increase over the next 20–30 years. However, the introduction of more efficient steam cycles will improve the emission performance of these plants over the short term. To achieve a reduction in carbon emissions from coal-fired plant, however, it will be necessary to develop and introduce carbon capture and sequestration technologies. Given adequate investment, these technologies should be capable of commercial development by
ca
2020.
An overview of geoengineering of climate using stratospheric sulphate aerosols
Authors: Rasch Philip J , Tilmes Simone , Turco Richard P , Robock Alan , Oman Luke , Chen Chih-Chieh (Jack) , Stenchikov Georgiy L , Garcia Rolando R
Published: August 2008

We provide an overview of geoengineering by stratospheric sulphate aerosols. The state of understanding about this topic as of early 2008 is reviewed, summarizing the past 30 years of work in the area, highlighting some very recent studies using climate models, and discussing methods used to deliver sulphur species to the stratosphere. The studies reviewed here suggest that sulphate aerosols can counteract the globally averaged temperature increase associated with increasing greenhouse gases, and reduce changes to some other components of the Earth system. There are likely to be remaining regional climate changes after geoengineering, with some regions experiencing significant changes in temperature or precipitation. The aerosols also serve as surfaces for heterogeneous chemistry resulting in increased ozone depletion. The delivery of sulphur species to the stratosphere in a way that will produce particles of the right size is shown to be a complex and potentially very difficult task. Two simple delivery scenarios are explored, but similar exercises will be needed for other suggested delivery mechanisms. While the introduction of the geoengineering source of sulphate aerosol will perturb the sulphur cycle of the stratosphere signicantly, it is a small perturbation to the total (stratosphere and troposphere) sulphur cycle. The geoengineering source would thus be a small contributor to the total global source of ‘acid rain’ that could be compensated for through improved pollution control of anthropogenic tropospheric sources. Some areas of research remain unexplored. Although ozone may be depleted, with a consequent increase to solar ultraviolet-B (UVB) energy reaching the surface and a potential impact on health and biological populations, the aerosols will also scatter and attenuate this part of the energy spectrum, and this may compensate the UVB enhancement associated with ozone depletion. The aerosol will also change the ratio of diffuse to direct energy reaching the surface, and this may influence ecosystems. The impact of geoengineering on these components of the Earth system has not yet been studied. Representations for the formation, evolution and removal of aerosol and distribution of particle size are still very crude, and more work will be needed to gain confidence in our understanding of the deliberate production of this class of aerosols and their role in the climate system.
Global and Arctic climate engineering: numerical model studies
Authors: Caldeira Ken , Wood Lowell
Published: August 2008

We perform numerical simulations of the atmosphere, sea ice and upper ocean to examine possible effects of diminishing incoming solar radiation, insolation, on the climate system. We simulate both global and Arctic climate engineering in idealized scenarios in which insolation is diminished above the top of the atmosphere. We consider the Arctic scenarios because climate change is manifesting most strongly there. Our results indicate that, while such simple insolation modulation is unlikely to perfectly reverse the effects of greenhouse gas warming, over a broad range of measures considering both temperature and water, an engineered high CO
2
climate can be made much more similar to the low CO
2
climate than would be a high CO
2
climate in the absence of such engineering. At high latitudes, there is less sunlight deflected per unit albedo change but climate system feedbacks operate more powerfully there. These two effects largely cancel each other, making the global mean temperature response per unit top-of-atmosphere albedo change relatively insensitive to latitude. Implementing insolation modulation appears to be feasible.
A geophysiologist's thoughts on geoengineering
Authors: Lovelock James
Published: August 2008

The Earth is now recognized as a self-regulating system that includes a reactive biosphere; the system maintains a long-term steady-state climate and surface chemical composition favourable for life. We are perturbing the steady state by changing the land surface from mainly forests to farm land and by adding greenhouse gases and aerosol pollutants to the air. We appear to have exceeded the natural capacity to counter our perturbation and consequently the system is changing to a new and as yet unknown but probably adverse state. I suggest here that we regard the Earth as a physiological system and consider amelioration techniques, geoengineering, as comparable to nineteenth century medicine.
Global temperature stabilization via controlled albedo enhancement of low-level maritime clouds
Authors: Latham John , Rasch Philip , Chen Chih-Chieh , Kettles Laura , Gadian Alan , Gettelman Andrew , Morrison Hugh , Bower Keith , Choularton Tom
Published: August 2008

An assessment is made herein of the proposal that controlled global cooling sufficient to balance global warming resulting from increasing atmospheric CO
2
concentrations might be achieved by seeding low-level, extensive maritime clouds with seawater particles that act as cloud condensation nuclei, thereby activating new droplets and increasing cloud albedo (and possibly longevity). This paper focuses on scientific and meteorological aspects of the scheme. Associated technological issues are addressed in a companion paper.

Analytical calculations, cloud modelling and (particularly) GCM computations suggest that, if outstanding questions are satisfactorily resolved, the controllable, globally averaged negative forcing resulting from deployment of this scheme might be sufficient to balance the positive forcing associated with a doubling of CO
2
concentration. This statement is supported quantitatively by recent observational evidence from three disparate sources. We conclude that this technique could thus be adequate to hold the Earth's temperature constant for many decades.

More work—especially assessments of possible meteorological and climatological ramifications—is required on several components of the scheme, which possesses the advantages that (i) it is ecologically benign—the only raw materials being wind and seawater, (ii) the degree of cooling could be controlled, and (iii) if unforeseen adverse effects occur, the system could be immediately switched off, with the forcing returning to normal within a few days (although the response would take a much longer time).
Ocean fertilization: a potential means of geoengineering?
Authors: Lampitt R.S , Achterberg E.P , Anderson T.R , Hughes J.A , Iglesias-Rodriguez M.D , Kelly-Gerreyn B.A , Lucas M , Popova E.E , Sanders R , Shepherd J.G , Smythe-Wright D , Yool A
Published: August 2008

The oceans sequester carbon from the atmosphere partly as a result of biological productivity. Over much of the ocean surface, this productivity is limited by essential nutrients and we discuss whether it is likely that sequestration can be enhanced by supplying limiting nutrients. Various methods of supply have been suggested and we discuss the efficacy of each and the potential side effects that may develop as a result. Our conclusion is that these methods have the potential to enhance sequestration but that the current level of knowledge from the observations and modelling carried out to date does not provide a sound foundation on which to make clear predictions or recommendations. For ocean fertilization to become a viable option to sequester CO
2
, we need more extensive and targeted fieldwork and better mathematical models of ocean biogeochemical processes. Models are needed both to interpret field observations and to make reliable predictions about the side effects of large-scale fertilization. They would also be an essential tool with which to verify that sequestration has effectively taken place. There is considerable urgency to address climate change mitigation and this demands that new fieldwork plans are developed rapidly. In contrast to previous experiments, these must focus on the specific objective which is to assess the possibilities of CO
2
sequestration through fertilization.
Carbon neutral hydrocarbons
Authors: Zeman Frank S , Keith David W
Published: August 2008

Reducing greenhouse gas emissions from the transportation sector may be the most difficult aspect of climate change mitigation. We suggest that carbon neutral hydrocarbons (CNHCs) offer an alternative pathway for deep emission cuts that complement the use of decarbonized energy carriers. Such fuels are synthesized from atmospheric carbon dioxide (CO
2
) and carbon neutral hydrogen. The result is a liquid fuel compatible with the existing transportation infrastructure and therefore capable of a gradual deployment with minimum supply disruption. Capturing the atmospheric CO
2
can be accomplished using biomass or industrial methods referred to as air capture. The viability of biomass fuels is strongly dependent on the environmental impacts of biomass production. Strong constraints on land use may favour the use of air capture. We conclude that CNHCs may be a viable alternative to hydrogen or conventional biofuels and warrant a comparable level of research effort and support.
The next generation of iron fertilization experiments in the Southern Ocean
Authors: Smetacek V , Naqvi S.W.A
Published: August 2008

Of the various macro-engineering schemes proposed to mitigate global warming, ocean iron fertilization (OIF) is one that could be started at short notice on relevant scales. It is based on the reasoning that adding trace amounts of iron to iron-limited phytoplankton of the Southern Ocean will lead to blooms, mass sinking of organic matter and ultimately sequestration of significant amounts of atmospheric carbon dioxide (CO
2
) in the deep sea and sediments. This iron hypothesis, proposed by John Martin in 1990 (Martin 1990
Paleoceanography
5
, 1–13), has been tested by five mesoscale experiments that provided strong support for its first condition: stimulation of a diatom bloom accompanied by significant CO
2
drawdown. Nevertheless, a number of arguments pertaining to the fate of bloom biomass, the ratio of iron added to carbon sequestered and various side effects of fertilization, continue to cast doubt on its efficacy. The idea is also unpopular with the public because it is perceived as meddling with nature. However, this apparent consensus against OIF is premature because none of the published experiments were specifically designed to test its second condition pertaining to the fate of iron-induced organic carbon. Furthermore, the arguments on side effects are based on worst-case scenarios. These doubts, formulated as hypotheses, need to be tested in the next generation of OIF experiments. We argue that such experiments, if carried out at appropriate scales and localities, will not only show whether the technique will work, but will also reveal a wealth of insights on the structure and functioning of pelagic ecosystems in general and the krill-based Southern Ocean ecosystem, in particular. The outcomes of current models on the efficacy and side effects of OIF differ widely, so data from adequately designed experiments are urgently needed for realistic parametrization. OIF is likely to boost zooplankton stocks, including krill, which could have a positive effect on recovery of the great whale populations. Negative effects of possible commercialization of OIF can be controlled by the establishment of an international body headed by scientists to supervise and monitor its implementation.
Geoengineering: could we or should we make it work?
Authors: Schneider Stephen H
Published: August 2008

Schemes to modify large-scale environment systems or control climate have been proposed for over 50 years to (i) increase temperatures in high latitudes, (ii) increase precipitation, (iii) decrease sea ice, (iv) create irrigation opportunities, or (v) offset potential global warming by injecting iron in the oceans or sea-salt aerosol in the marine boundary layer or spreading dust in the stratosphere to reflect away an amount of solar energy equivalent to the amount of heat trapped by increased greenhouse gases from human activities. These and other proposed geoengineering schemes are briefly reviewed. Recent schemes to intentionally modify climate have been proposed as either cheaper methods to counteract inadvertent climatic modifications than conventional mitigation techniques such as carbon taxes or pollutant emissions regulations or as a counter to rising emissions as governments delay policy action. Whereas proponents argue cost-effectiveness or the need to be prepared if mitigation and adaptation policies are not strong enough or enacted quickly enough to avoid the worst widespread impacts, critics point to the uncertainty that (i) any geoengineering scheme would work as planned or (ii) that the many centuries of international political stability and cooperation needed for the continuous maintenance of such schemes to offset century-long inadvertent effects is socially feasible. Moreover, the potential exists for transboundary conflicts should negative climatic events occur during geoengineering activities.
Renal Peripheral Neuroectodermal Tumor Presenting at Age 78: Case Report
Authors: Koski Michelle E. , Tedesco Jason M. , Clark Peter E.
Published: September 2008

Primitive neuroectodermal tumor (PNET) of the kidney is a rare and aggressive tumor, often presenting in advanced stages and progressing rapidly. Renal PNET (rPNET) may affect a wide age spectrum, but the majority of cases are in young adults. We present a case of advanced rPNET in a 78-year-old woman. To our knowledge, this is the most advanced age of presentation of this neoplasm to date. We report on her presentation and management, and discuss the current clinical management of this tumor.
Gene prediction in novel fungal genomes using an ab initio algorithm with unsupervised training
Authors: Ter-Hovhannisyan Vardges , Lomsadze Alexandre , Chernoff Yury O. , Borodovsky Mark
Published: August 2008

We describe a new ab initio algorithm, GeneMark-ES version 2, that identifies protein-coding genes in fungal genomes. The algorithm does not require a predetermined training set to estimate parameters of the underlying hidden Markov model (HMM). Instead, the anonymous genomic sequence in question is used as an input for iterative unsupervised training. The algorithm extends our previously developed method tested on genomes of Arabidopsis thaliana, Caenorhabditis elegans, and Drosophila melanogaster. To better reflect features of fungal gene organization, we enhanced the intron submodel to accommodate sequences with and without branch point sites. This design enables the algorithm to work equally well for species with the kinds of variations in splicing mechanisms seen in the fungal phyla Ascomycota, Basidiomycota, and Zygomycota. Upon self-training, the intron submodel switches on in several steps to reach its full complexity. We demonstrate that the algorithm accuracy, both at the exon and the whole gene level, is favorably compared to the accuracy of gene finders that employ supervised training. Application of the new method to known fungal genomes indicates substantial improvement over existing annotations. By eliminating the effort necessary to build comprehensive training sets, the new algorithm can streamline and accelerate the process of annotation in a large number of fungal genome sequencing projects.
Tomato γ-Glutamylhydrolases: Expression, Characterization, and Evidence for Heterodimer Formation
Authors: Akhtar Tariq A. , McQuinn Ryan P. , Naponelli Valeria , Gregory Jesse F. , Giovannoni James J. , Hanson Andrew D.
Published: August 2008

Folates typically have γ-linked polyglutamyl tails that make them better enzyme substrates and worse transport substrates than the unglutamylated forms. The tail can be shortened or removed by the vacuolar enzyme γ-glutamyl hydrolase (GGH). It is known that GGH is active only as a dimer and that plants can have several GGH genes whose homodimeric products differ functionally. However, it is not known whether GGH dimers dissociate under in vivo conditions, whether heterodimers form, or how heterodimerization impacts enzyme activity. These issues were explored using the GGH system of tomato (Solanum lycopersicum). Tomato has three GGH genes that, like those in other eudicots, apparently diverged recently. LeGGH1 and LeGGH2 are expressed in fruit and all other organs, whereas LeGGH3 is expressed mainly in flower buds. LeGGH1 and LeGGH2 homodimers differ in bond cleavage preference; the LeGGH3 homodimer is catalytically inactive. Homodimers did not dissociate in physiological conditions. When coexpressed in Escherichia coli, LeGGH1 and LeGGH2 formed heterodimers with an intermediate bond cleavage preference, whereas LeGGH3 formed heterodimers with LeGGH1 or LeGGH2 that had one-half the activity of the matching homodimer. E. coli cells expressing LeGGH2 showed approximately 85% reduction in folate polyglutamates, but cells expressing LeGGH3 did not, confirming that LeGGH2 can function in vivo and LeGGH3 cannot. The formation of LeGGH1-LeGGH2 heterodimers was demonstrated in planta using bimolecular fluorescence complementation. Plant GGH heterodimers thus appear to form wherever different GGH genes are expressed simultaneously and to have catalytic characteristics midway between those of the corresponding homodimers.
ArabidopsisTONNEAU1 Proteins Are Essential for Preprophase Band Formation and Interact with Centrin
Authors: Azimzadeh Juliette , Nacry Philippe , Christodoulidou Anna , Drevensek Stéphanie , Camilleri Christine , Amiour Nardjis , Parcy François , Pastuglia Martine , Bouchez David
Published: August 2008

Plant cells have specific microtubule structures involved in cell division and elongation. The tonneau1 (ton1) mutant of Arabidopsis thaliana displays drastic defects in morphogenesis, positioning of division planes, and cellular organization. These are primarily caused by dysfunction of the cortical cytoskeleton and absence of the preprophase band of microtubules. Characterization of the ton1 insertional mutant reveals complex chromosomal rearrangements leading to simultaneous disruption of two highly similar genes in tandem, TON1a and TON1b. TON1 proteins are conserved in land plants and share sequence motifs with human centrosomal proteins. The TON1 protein associates with soluble and microsomal fractions of Arabidopsis cells, and a green fluorescent protein–TON1 fusion labels cortical cytoskeletal structures, including the preprophase band and the interphase cortical array. A yeast two-hybrid screen identified Arabidopsis centrin as a potential TON1 partner. This interaction was confirmed both in vitro and in plant cells. The similarity of TON1 with centrosomal proteins and its interaction with centrin, another key component of microtubule organizing centers, suggests that functions involved in the organization of microtubule arrays by the centrosome were conserved across the evolutionary divergence between plants and animals.
The Cold-Inducible CBF1 Factor–Dependent Signaling Pathway Modulates the Accumulation of the Growth-Repressing DELLA Proteins via Its Effect on Gibberellin Metabolism
Authors: Achard Patrick , Gong Fan , Cheminant Soizic , Alioua Malek , Hedden Peter , Genschik Pascal
Published: August 2008

Plants have evolved robust mechanisms to respond and adapt to unfavorable environmental conditions, such as low temperature. The C-repeat/drought-responsive element binding factor CBF1/DREB1b gene encodes a transcriptional activator transiently induced by cold that controls the expression of a set of genes responding to low temperature (the CBF regulon). Constitutive expression of CBF1 confers freezing tolerance but also slows growth. Here, we propose that low temperature–induced CBF1 expression restrains growth at least in part by allowing the accumulation of DELLAs, a family of nuclear growth-repressing proteins, the degradation of which is stimulated by gibberellin (GA). We show that cold/CBF1 enhances the accumulation of a green fluorescent protein (GFP)–tagged DELLA protein (GFP-RGA) by reducing GA content through stimulating expression of GA-inactivating GA 2-oxidase genes. Accordingly, transgenic plants that constitutively express CBF1 accumulate less bioactive GA and as a consequence exhibit dwarfism and late flowering. Both phenotypes are suppressed when CBF1 is expressed in a line lacking two DELLA proteins, GA-INSENSITIVE and REPRESSOR OF GA1-3. In addition, we show that DELLAs contribute significantly to CBF1-induced cold acclimation and freezing tolerance by a mechanism that is distinct from the CBF regulon. We conclude that DELLAs are components of the CBF1-mediated cold stress response.