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1.
Proc Natl Acad Sci U S A ; 116(29): 14526-14531, 2019 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-31262824

RESUMO

Carbon stored in harvested wood products (HWPs) can affect national greenhouse gas (GHG) inventories, in which the production and end use of HWPs play a key role. The Intergovernmental Panel on Climate Change (IPCC) provides guidance on HWP carbon accounting, which is sensitive to future developments of socioeconomic factors including population, income, and trade. We estimated the carbon stored within HWPs from 1961 to 2065 for 180 countries following IPCC carbon-accounting guidelines, consistent with Food and Agriculture Organization of the United Nations (FAOSTAT) historical data and plausible futures outlined by the shared socioeconomic pathways. We found that the global HWP pool was a net annual sink of 335 Mt of CO2 equivalent (CO2e)⋅y-1 in 2015, offsetting substantial amounts of industrial processes within some countries, and as much as 441 Mt of CO2e⋅y-1 by 2030 under certain socioeconomic developments. Furthermore, there is a considerable sequestration gap (71 Mt of CO2e⋅y-1 of unaccounted carbon storage in 2015 and 120 Mt of CO2e⋅y-1 by 2065) under current IPCC Good Practice Guidance, as traded feedstock is ineligible for national GHG inventories. However, even under favorable socioeconomic conditions, and when accounting for the sequestration gap, carbon stored annually in HWPs is <1% of global emissions. Furthermore, economic shocks can turn the HWP pool into a carbon source either long-term-e.g., the collapse of the USSR-or short-term-e.g., the US economic recession of 2008/09. In conclusion, carbon stored within end-use HWPs varies widely across countries and depends on evolving market forces.

2.
J Fish Biol ; 76(6): 1312-28, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20537016

RESUMO

The reproductive biology of the Panama graysby Cephalopholis panamensis was studied from collections and behavioural observations made in the Gulf of California from 2001 to 2006. Histological examinations, particularly the identification of gonads undergoing sexual transition, confirmed a protogynous hermaphroditic sexual pattern. The population structure and mating behaviour provided further support for protogyny. Size and age distributions by sex were bimodal, with males larger and older than females and sex ratios biased towards females. Mating groups consisted of a large male and several smaller females, and courtship occurred in pairs during the evening. Results on spawning periodicity and seasonality were incomplete, but histological data, monthly gonado-somatic indices (I(G)) and behavioural observations suggest that adults spawned around the full moon from May to September. Certain aspects of their reproductive biology (e.g. protogyny and low egg production) indicate that C. panamensis is particularly vulnerable to fishing and would benefit from a management policy in Mexico.


Assuntos
Bass/fisiologia , Reprodução/fisiologia , Comportamento Sexual Animal/fisiologia , Animais , Bass/anatomia & histologia , Feminino , Gônadas/anatomia & histologia , Gônadas/fisiologia , Organismos Hermafroditas , Masculino , México , Periodicidade , Densidade Demográfica , Processos de Determinação Sexual/veterinária , Razão de Masculinidade
3.
Nat Commun ; 8(1): 152, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28751664

RESUMO

Appropriate integration of GABAergic interneurons into nascent cortical circuits is critical for ensuring normal information processing within the brain. Network and cognitive deficits associated with neurological disorders, such as schizophrenia, that result from NMDA receptor-hypofunction have been mainly attributed to dysfunction of parvalbumin-expressing interneurons that paradoxically express low levels of synaptic NMDA receptors. Here, we reveal that throughout postnatal development, thalamic, and entorhinal cortical inputs onto hippocampal neurogliaform cells are characterized by a large NMDA receptor-mediated component. This NMDA receptor-signaling is prerequisite for developmental programs ultimately responsible for the appropriate long-range AMPAR-mediated recruitment of neurogliaform cells. In contrast, AMPAR-mediated input at local Schaffer-collateral synapses on neurogliaform cells remains normal following NMDA receptor-ablation. These afferent specific deficits potentially impact neurogliaform cell mediated inhibition within the hippocampus and our findings reveal circuit loci implicating this relatively understudied interneuron subtype in the etiology of neurodevelopmental disorders characterized by NMDA receptor-hypofunction.Proper brain function depends on the correct assembly of excitatory and inhibitory neurons into neural circuits. Here the authors show that during early postnatal development in mice, NMDAR signaling via activity of long-range synaptic inputs onto neurogliaform cells is required for their appropriate integration into the hippocampal circuitry.


Assuntos
Neurônios GABAérgicos/metabolismo , Hipocampo/metabolismo , Interneurônios/metabolismo , Proteínas do Tecido Nervoso/genética , Neuroglia/metabolismo , Plasticidade Neuronal/genética , Neurônios Aferentes/metabolismo , Receptores de N-Metil-D-Aspartato/genética , Animais , Região CA3 Hipocampal/crescimento & desenvolvimento , Região CA3 Hipocampal/metabolismo , Dendritos/metabolismo , Córtex Entorrinal/metabolismo , Hipocampo/crescimento & desenvolvimento , Camundongos , Camundongos Knockout , Proteínas do Tecido Nervoso/metabolismo , Parvalbuminas/metabolismo , Técnicas de Patch-Clamp , Receptores de AMPA/metabolismo , Receptores de N-Metil-D-Aspartato/metabolismo , Sinapses/metabolismo , Tálamo/metabolismo
4.
J Cataract Refract Surg ; 16(4): 495-500, 1990 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-2380933

RESUMO

A series of explanted intraocular lenses (IOLs) and autopsy globes containing IOLs that had previously had Nd:YAG laser posterior capsulotomy were analyzed at the Intermountain Ocular Research Center. A broad spectrum of laser-induced IOL damage was found. In the majority of instances, the damage was classified as mild and consisted of tiny pits on the IOLs' posterior surface. These pits would not be expected to produce any visually significant consequences. Moderate damage consisted of larger, more extensive pitting, craters, and small cracks. The most severely damaged IOLs showed extensive cracking and focal fracturing of the optic. Extensive damage may result in unacceptable visual blurring, distortion, and glare which in extreme cases may warrant IOL explantation, as presented in a case report.


Assuntos
Terapia a Laser/efeitos adversos , Cápsula do Cristalino/cirurgia , Cristalino/cirurgia , Lentes Intraoculares , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Microscopia Eletrônica de Varredura , Acuidade Visual
5.
J Cataract Refract Surg ; 16(5): 597-602, 1990 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-2231377

RESUMO

Following insertion of either Healon (sodium hyaluronate) or Viscoat (sodium chondroitin sulfate-sodium hyaluronate) into the anterior chamber of human eye bank eyes, a controlled amount of small air bubbles was introduced into the anterior chamber during phacoemulsification. After vital staining, damage to endothelial cells in the central cornea was quantified. Endothelial damage averaged 4.5% in eyes in which no viscoelastic was used (positive control), whereas damage was only 0.4% (P less than .001) in eyes in which a viscoelastic was inserted but no air bubbles were introduced (negative control). Endothelial damage in test specimens using air plus Healon averaged 4.9%. Damage in test specimens using air plus Viscoat averaged 0.3% (P less than .02). As demonstrated by scanning electron microscopy, many areas in the positive controls and in the Healon test specimens were damaged too extensively to quantitate accurately by the method we used. Thus, Viscoat may prevent or lessen damage to the corneal endothelium by small air bubbles during phacoemulsification.


Assuntos
Ar , Extração de Catarata/efeitos adversos , Condroitina/uso terapêutico , Endotélio Corneano/ultraestrutura , Ácido Hialurônico/uso terapêutico , Câmara Anterior , Contagem de Células , Sulfatos de Condroitina , Combinação de Medicamentos , Estudos de Avaliação como Assunto , Bancos de Olhos , Humanos , Microscopia Eletrônica de Varredura , Distribuição Aleatória
6.
J Cataract Refract Surg ; 17(2): 163-7, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2040973

RESUMO

We analyzed 740 penetrating keratoplasty specimens received at the Intermountain Ocular Research Center from 1981 through 1988. These corneal specimens were categorized by clinical indications for removal and pathologic confirmation of the clinical findings. Keratoconus was the most common indication for a penetrating keratoplasty (22.8%). This was closely followed by pseudophakie bullous keratopathy (21.8%), regraft (13.2%), scarring (8.9%), aphakic bullous keratopathy (6.4%), and Fuchs' endothelial dystrophy (5.8%). Since 1984, pseudophakic bullous keratopathy has surpassed keratoconus as the most common indication for penetrating keratoplasty (27.3% vs. 20.2%). Pseudophakic bullous keratopathy was found more commonly than keratoconus in each of the last four years of this study. The most common type of intraocular lens associated with pseudophakic bullous keratopathy was an anterior chamber lens (52.8%), with iris-fixated (26.7%) and posterior chamber (17.4%) lenses seen less frequently.


Assuntos
Doenças da Córnea/patologia , Ceratoplastia Penetrante , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Câmara Anterior/cirurgia , Criança , Pré-Escolar , Feminino , Distrofia Endotelial de Fuchs/patologia , Humanos , Incidência , Lactente , Iris/cirurgia , Ceratocone/patologia , Lentes Intraoculares , Masculino , Estudos Retrospectivos
7.
Aquat Conserv ; 22(2): 232-261, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25505830

RESUMO

The Chagos Archipelago was designated a no-take marine protected area (MPA) in 2010; it covers 550 000 km2, with more than 60 000 km2 shallow limestone platform and reefs. This has doubled the global cover of such MPAs.It contains 25-50% of the Indian Ocean reef area remaining in excellent condition, as well as the world's largest contiguous undamaged reef area. It has suffered from warming episodes, but after the most severe mortality event of 1998, coral cover was restored after 10 years.Coral reef fishes are orders of magnitude more abundant than in other Indian Ocean locations, regardless of whether the latter are fished or protected.Coral diseases are extremely low, and no invasive marine species are known.Genetically, Chagos marine species are part of the Western Indian Ocean, and Chagos serves as a 'stepping-stone' in the ocean.The no-take MPA extends to the 200 nm boundary, and. includes 86 unfished seamounts and 243 deep knolls as well as encompassing important pelagic species.On the larger islands, native plants, coconut crabs, bird and turtle colonies were largely destroyed in plantation times, but several smaller islands are in relatively undamaged state.There are now 10 'important bird areas', coconut crab density is high and numbers of green and hawksbill turtles are recovering.Diego Garcia atoll contains a military facility; this atoll contains one Ramsar site and several 'strict nature reserves'. Pollutant monitoring shows it to be the least polluted inhabited atoll in the world. Today, strict environmental regulations are enforced.Shoreline erosion is significant in many places. Its economic cost in the inhabited part of Diego Garcia is very high, but all islands are vulnerable.Chagos is ideally situated for several monitoring programmes, and use is increasingly being made of the archipelago for this purpose.

9.
Acta Anaesthesiol Scand ; 49(1): 6-15, 2005 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-15675975

RESUMO

BACKGROUND: The use of sodium bicarbonate (SB) in cardiopulmonary resuscitation (CPR) is controversial. This study analyzes the effects of SB use on CPR outcome in the Brain Resuscitation Clinical Trial III (BRCT III), which was a multicenter randomized trial comparing high-dose to standard-dose epinephrine during CPR. Sodium bicarbonate use in BRCT III was optional. METHODS: The entire BRCT III database was reviewed. Analysis included only patients who arrested out of the hospital and whose time from collapse to initiation of ACLS was no longer than 30 min (total n = 2122 patients). Sodium bicarbonate use by the 16 participating study sites was analyzed. The study sites were divided according to their SB usage profile: 'low SB user' sites administered SB in less than 50% of CPRs and their first epinephrine to SB time exceeded 10 min; and 'high SB user' sites used SB in over 50% of CPRs and their first epinephrine to SB time was <10 min. RESULTS: Sites' SB usage rates ranged between 3.1% and 98.2% of CPRs. Sodium bicarbonate usage rates correlated inversely with the sites' intervals from collapse (r = - 0.579 P = 0.018) from initiation of ACLS (r = - 0.685 P = 0.003) and from first epinephrine (r = - 0.611 P = 0.012) to SB administration. Mean ROSC rate in the 'high SB user' sites was 33.5% (CI = 30.0-37.0) compared to 25.7% (CI = 23.1-28.4) in the 'low SB user' sites. In the 'high SB user' sites, hospital discharge rate was 5.3% (CI = 3.6-7.0) compared to 3% (CI = 2.0-4.0) in the 'low SB user' sites, and 5.3% (CI = 3.6-7.0) had a favorable neurological outcome compared to 2.1% (CI = 1.2-3.0) in the 'low SB user' sites. Collapse to ACLS interval was 8.5 min (CI = 8.1-9.0) in the 'high SB user' sites compared to 10.2 min (CI = 9.8-10.6) in the 'low SB user' sites, and their ACLS to first epinephrine interval was 7.0 min (CI = 6.5-7.5) compared to 9.7 min (CI = 9.3-10.2). Multivariate regression analysis found that belonging to 'high SB user' sites independently increased the chances for ROSC (OR 1.36, CI 1.08-1.7) and for achieving a good neurological outcome (OR 2.18, CI 1.23-3.86). CONCLUSIONS: Earlier and more frequent use of SB was associated with higher early resuscitability rates and with better long-term outcome. Sodium bicarbonate may be beneficial during CPR, and it should be subjected to a randomized clinical trial.


Assuntos
Reanimação Cardiopulmonar , Serviços Médicos de Emergência , Bicarbonato de Sódio/uso terapêutico , Acidose/tratamento farmacológico , Idoso , Encéfalo/fisiologia , Soluções Tampão , Relação Dose-Resposta a Droga , Epinefrina/uso terapêutico , Feminino , Parada Cardíaca/etiologia , Parada Cardíaca/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto , Simpatomiméticos/uso terapêutico , Taquicardia Ventricular/terapia , Resultado do Tratamento , Fibrilação Ventricular/terapia
10.
Mol Phylogenet Evol ; 19(1): 121-30, 2001 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-11286497

RESUMO

Historically, attempts to elucidate evolutionary relationships among members of the genus Epinephelus (Teleostei: Serranidae), commonly known as groupers, have been hindered by the overwhelming number of species (98, sensu stricto), a pan global distribution, and the lack of morphological specializations traditionally used in ichthyological classification. To date, no comprehensive phylogenetic study, morphological or molecular, to evaluate the monophyly of this genus has been presented. In this study, previous hypotheses regarding the relationships among the American grouper species and the allied genera were evaluated by examination of mitochondrial DNA sequences of the 16S ribosomal DNA region. A 590-bp region of the 16S rDNA gene was amplified using a universal primer pair for 42 serranid species, including members of the genera Epinephelus, Mycteroperca, and Paranthias from the New World and selected Indo-Pacific congeners. Maximum-parsimony criteria and neighbor-joining analysis dispute the monophyly of the American Epinephelus species as previously hypothesized. The data support the monophyly of Cephalopholis only with the inclusion of the morphologically distinct Paranthias and the monophyly of Mycteroperca with the inclusion of the Indo-Pacific Anyperodon leucogrammicus.


Assuntos
Peixes/genética , Filogenia , RNA Ribossômico 16S/genética , Animais , DNA Mitocondrial/química , DNA Mitocondrial/genética , Evolução Molecular , Peixes/classificação , Dados de Sequência Molecular , Análise de Sequência de DNA
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