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1.
Nat Commun ; 14(1): 2447, 2023 Apr 28.
Article in English | MEDLINE | ID: mdl-37117183

ABSTRACT

Offshore wind power, with accelerated declining levelized costs, is emerging as a critical building-block to fully decarbonize the world's largest CO2 emitter, China. However, system integration barriers as well as system balancing costs have not been quantified yet. Here we develop a bottom-up model to test the grid accommodation capabilities and design the optimal investment plans for offshore wind power considering resource distributions, hourly power system simulations, and transmission/storage/hydrogen investments. Results indicate that grid integration barriers exist currently at the provincial level. For 2030, optimized offshore wind investment levels should be doubled compared with current government plans, and provincial allocations should be significantly improved considering both resource quality and grid conditions. For 2050, offshore wind capacity in China could reach as high as 1500 GW, prompting a paradigm shift in national transmission structure, favoring long-term storage in the energy portfolio, enabling green hydrogen production in coastal demand centers, resulting in the world's largest wind power market.

2.
Pediatr Rev ; 43(6): 356-359, 2022 06 01.
Article in English | MEDLINE | ID: mdl-36121421
3.
iScience ; 25(6): 104399, 2022 Jun 17.
Article in English | MEDLINE | ID: mdl-35633943

ABSTRACT

The paper explores options for a 2050 carbon free energy future for India. Onshore wind and solar sources are projected as the dominant primary contributions to this objective. The analysis envisages an important role for so-called green hydrogen produced by electrolysis fueled by these carbon free energy sources. This hydrogen source can be used to accommodate for the intrinsic variability of wind and solar complementing opportunities for storage of power by batteries and pumped hydro. The green source of hydrogen can be used also to supplant current industrial uses of gray hydrogen produced in the Indian context largely from natural gas with important related emissions of CO2. The paper explores further options for use of green hydrogen to lower emissions from otherwise difficult to abate sectors of both industry and transport. The analysis is applied to identify the least cost options to meet India's zero carbon future.

4.
Nat Commun ; 12(1): 6953, 2021 Nov 29.
Article in English | MEDLINE | ID: mdl-34845233

ABSTRACT

The Japanese government has announced a commitment to net-zero greenhouse gas emissions by 2050. It envisages an important role for hydrogen in the nation's future energy economy. This paper explores the possibility that a significant source for this hydrogen could be produced by electrolysis fueled by power generated from offshore wind in China. Hydrogen could be delivered to Japan either as liquid, or bound to a chemical carrier such as toluene, or as a component of ammonia. The paper presents an analysis of factors determining the ultimate cost for this hydrogen, including expenses for production, storage, conversion, transport, and treatment at the destination. It concludes that the Chinese source could be delivered at a volume and cost consistent with Japan's idealized future projections.

5.
Nat Commun ; 11(1): 4750, 2020 Sep 21.
Article in English | MEDLINE | ID: mdl-32958940

ABSTRACT

This paper considers options for a future Indian power economy in which renewables, wind and solar, could meet 80% of anticipated 2040 power demand supplanting the country's current reliance on coal. Using a cost optimization model, here we show that renewables could provide a source of power cheaper or at least competitive with what could be supplied using fossil-based alternatives. The ancillary advantage would be a significant reduction in India's future power sector related emissions of CO2. Using a model in which prices for wind turbines and solar PV systems are assumed to continue their current decreasing trend, we conclude that an investment in renewables at a level consistent with meeting 80% of projected 2040 power demand could result in a reduction of 85% in emissions of CO2 relative to what might be expected if the power sector were to continue its current coal dominated trajectory.

6.
Nat Protoc ; 15(6): 1992-2023, 2020 06.
Article in English | MEDLINE | ID: mdl-32405052

ABSTRACT

Cranial microsurgery is an essential procedure for accessing the brain through the skull that can be used to introduce neural probes that measure and manipulate neural activity. Neuroscientists have typically used tools such as high-speed drills adapted from dentistry to perform these procedures. As the number of technologies available for neuroscientists has increased, the corresponding cranial microsurgery procedures to deploy them have become more complex. Using a robotic tool that automatically performs these procedures could standardize cranial microsurgeries across neuroscience laboratories and democratize the more challenging procedures. We have recently engineered a robotic surgery platform that utilizes principles of computer numerical control (CNC) machining to perform a wide variety of automated cranial procedures. Here, we describe how to adapt, configure and use an inexpensive desktop CNC mill equipped with a custom-built surface profiler for performing CNC-guided microsurgery on mice. Detailed instructions are provided to utilize this 'Craniobot' for performing circular craniotomies for coverslip implantation, large craniotomies for implanting transparent polymer skulls for cortex-wide imaging access and skull thinning for intact skull imaging. The Craniobot can be set up in <2 weeks using parts that cost <$1,500, and we anticipate that the Craniobot could be easily adapted for use in other small animals.


Subject(s)
Craniotomy/instrumentation , Microsurgery/instrumentation , Robotic Surgical Procedures/instrumentation , Skull/surgery , Animals , Craniotomy/methods , Equipment Design , Female , Male , Mice , Mice, Inbred C57BL , Microsurgery/methods , Robotic Surgical Procedures/methods
7.
Sci Adv ; 6(8): eaax9571, 2020 Feb.
Article in English | MEDLINE | ID: mdl-32128398

ABSTRACT

China has reduced growth in its emissions of greenhouse gases, partly attributable to major investments in onshore wind. By comparison, investments in offshore wind have been minor, limited until recently largely by perceptions of cost. Assimilated meteorological data are used here to assess future offshore wind potential for China. Analysis on a provincial basis indicates that the aggregate potential wind resource is 5.4 times larger than the current coastal demand for power. Recent experiences with markets in both Europe and the United States suggest that potential offshore resources in China could be exploited to cost-competitively provide 1148.3 TWh of energy in a high-cost scenario, 6383.4 TWh in a low-cost option, equivalent to between 36 and 200% of the total coastal energy demand after 2020. The analysis underscores notable benefits for offshore wind for China, with prospects for major reductions in greenhouse emissions with ancillary benefits for air quality.

8.
Sci Adv ; 5(7): eaav4157, 2019 Jul.
Article in English | MEDLINE | ID: mdl-31328156

ABSTRACT

As China makes every effort to control air pollution, India emerges as the world's most polluted country, receiving worldwide attention with frequent winter (boreal) haze extremes. In this study, we found that the interannual variability of wintertime aerosol pollution over northern India is regulated mainly by a combination of El Niño and the Antarctic Oscillation (AAO). Both El Niño sea surface temperature (SST) anomalies and AAO-induced Indian Ocean Meridional Dipole SST anomalies can persist from autumn to winter, offering prospects for a prewinter forecast of wintertime aerosol pollution over northern India. We constructed a multivariable regression model incorporating El Niño and AAO indices for autumn to predict wintertime AOD. The prediction exhibits a high degree of consistency with observation, with a correlation coefficient of 0.78 (P < 0.01). This statistical model could allow the Indian government to forecast aerosol pollution conditions in winter and accordingly improve plans for pollution control.

9.
Sci Rep ; 7(1): 16294, 2017 11 24.
Article in English | MEDLINE | ID: mdl-29176621

ABSTRACT

China hosts the world's largest market for wind-generated electricity. The financial return and carbon reduction benefits from wind power are sensitive to changing wind resources. Wind data derived from an assimilated meteorological database are used here to estimate what the wind generated electricity in China would have been on an hourly basis over the period 1979 to 2015 at a geographical resolution of approximately 50 km × 50 km. The analysis indicates a secular decrease in generating potential over this interval, with the largest declines observed for western Inner Mongolia (15 ± 7%) and the northern part of Gansu (17 ± 8%), two leading wind investment areas. The decrease is associated with long-term warming in the vicinity of the Siberian High (SH), correlated also with the observed secular increase in global average surface temperatures. The long-term trend is modulated by variability relating to the Pacific Decadal Oscillation (PDO) and the Arctic Oscillation (AO). A linear regression model incorporating indices for the PDO and AO, as well as the declining trend, can account for the interannual variability of wind power, suggesting that advances in long-term forecasting could be exploited to markedly improve management of future energy systems.

10.
Adipocyte ; 6(2): 102-111, 2017 04 03.
Article in English | MEDLINE | ID: mdl-28425850

ABSTRACT

Adipocyte sizes from adipose tissue of mature animals form a bimodal distribution, thus reporting mean cell size is misleading. The objectives of this study were to develop a robust method for testing bimodality of porcine adipocytes, describe the size distribution with an informative metric, and statistically test hypertrophy and appearance of new small adipocytes, possibly resulting from hyperplasia or lipid filling of previously divided fibroblastic cells. Ninety-three percent of adipose samples measured were bimodal (P < 0.0001); therefore, we describe and propose a method of testing hyperplasia or lipid filling of previously divided fibroblastic cells based upon the probability of an adipocyte falling into 2 chosen competing "bins" as adiposity increases. We also conclude that increased adiposity is correlated positively with an adipocyte being found in the minor mode (r = 0.46) and correlated negatively with an adipocyte being found in the major mode (r = -0.22), providing evidence of either hyperplasia or lipid filling of previously divided fibroblastic cells. We additionally conclude that as adiposity increases, the mode of the major distribution of cells occurs at a larger diameter of adipocyte, indicating hypertrophy.


Subject(s)
Adipocytes/cytology , Adipose Tissue/cytology , Biometry/methods , Adipocytes/physiology , Adipogenesis , Adipose Tissue/physiology , Adiposity/physiology , Animals , Cell Size , Hyperplasia/classification , Hyperplasia/pathology , Hyperplasia/veterinary , Hypertrophy , Models, Animal , Obesity/pathology , Swine
11.
J Oral Maxillofac Surg ; 73(2): 202, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25579004
12.
Contraception ; 89(5): 446-50, 2014 May.
Article in English | MEDLINE | ID: mdl-24560479

ABSTRACT

OBJECTIVE: The intrauterine contraceptive device (IUD) is one of the most effective contraceptive methods, but it remains underutilized, especially among adolescents. Little is known about how adolescents perceive IUDs. The objective of this study is to explore urban, minority female adolescents' attitudes and beliefs about IUDs and to identify barriers to IUD use. STUDY DESIGN: Qualitative semistructured interviews were conducted with 21 adolescents aged 14 to 21 years who had heard about the IUD but never used one personally. Participants were recruited from two urban school-based health clinics and one community health center. Individual interviews were audiotaped and transcribed. Themes were identified by two independent researchers through line-by-line analysis of interview transcripts. RESULTS: Fear of the IUD predominated. Respondents related fears about pain, expulsion, foreign body and the potential for physical harm. Common themes in support of the IUD included the IUD's superior efficacy compared to other contraceptive methods and the ability to use this method long term. Despite identifying IUD benefits, most respondents did not appear to think the method would be well suited for them. CONCLUSION: Though the IUD is safe and effective for adolescents, we found that urban female adolescents have many device-related concerns which must be addressed to make this method more acceptable. IMPLICATIONS: Understanding urban, minority adolescents' perspective on IUDs and their specific concerns about IUD method use can help clinicians provide targeted and relevant contraceptive counseling.


Subject(s)
Health Knowledge, Attitudes, Practice , Intrauterine Devices , Adolescent , Fear , Female , Humans , New York City , Young Adult
13.
Eur J Haematol ; 88(5): 416-21, 2012 May.
Article in English | MEDLINE | ID: mdl-22296221

ABSTRACT

INTRODUCTION: Granulocyte Colony-Stimulating Factor (G-CSF) is commonly used to maintain dose intensity in patients receiving ABVD chemotherapy (doxorubicin, bleomycin, vinblastine and dacarbazine) for Hodgkin lymphoma. However, the need for growth factor support is unclear, with studies suggesting that dose intensity can be maintained without G-CSF. Moreover, G-CSF is expensive (pegfilgrastim: EUR 1540/cycle; 300 µg filgrastim for 7 days: EUR 700/cycle) and is associated with side effects including bone pain and increased risk of bleomycin lung toxicity. Intermittent G-CSF may be an effective compromise, given that the effect of G-CSF on granulocyte precursors in vitro persists for 4-5 days after administration. After promising results of a pilot study, this schedule has been used subsequently in the majority of our patients receiving G-CSF as secondary prophylaxis for ABVD complicated by neutropenia. METHODS: Retrospective analysis of the incidence of febrile neutropenia and treatment delay in a variety of different G-CSF schedules used as secondary prophylaxis in patients receiving ABVD. RESULTS: 848 cycles in 85 consecutive patients were evaluated. Most patients (86%) received G-CSF, generally commenced prophylactically for neutropenia when cycle 1B was due. Intermittent G-CSF (typically given on days 4, 8 and 12) was used in 413 cycles compared with daily or pegylated G-CSF in 99 cycles. In patients receiving intermittent G-CSF, the median neutrophil count, across all cycles, was 7.3 × 10(9) /L (range: 1.4-47.1) when the next scheduled chemotherapy was due. There were two cases of febrile neutropenia (0.45%) and no treatment delays. One patient developed possible bleomycin toxicity. CONCLUSIONS: Intermittent G-CSF is effective in maintaining dose intensity in patients receiving ABVD.


Subject(s)
Antineoplastic Combined Chemotherapy Protocols/therapeutic use , Granulocyte Colony-Stimulating Factor/therapeutic use , Neutropenia/chemically induced , Adolescent , Adult , Aged , Antineoplastic Combined Chemotherapy Protocols/adverse effects , Bleomycin/adverse effects , Bleomycin/therapeutic use , Dacarbazine/adverse effects , Dacarbazine/therapeutic use , Dose-Response Relationship, Drug , Doxorubicin/adverse effects , Doxorubicin/therapeutic use , Female , Humans , Lymphoma, Non-Hodgkin/drug therapy , Male , Middle Aged , Retrospective Studies , Vinblastine/adverse effects , Vinblastine/therapeutic use , Young Adult
14.
J Food Sci ; 74(4): E167-76, 2009.
Article in English | MEDLINE | ID: mdl-19490321

ABSTRACT

Oxygen within the sealed package can reduce the quality of liquid-based food products with high oil content such as hot-filled meal-ready-to-eat (MRE) cheese spread, a component of military operational rations. The aim of this study was to test a novel oxygen absorber-containing laminate material and its ability to maintain and/or extend shelf life of a cheese-spread MRE item. An iron-based oxygen absorber (ABSO(2)RB(R)) activated by moisture was incorporated into the laminate and used to pack hot-filled cheese spread MREs. The kinetics of oxygen absorption due to humidity and temperature were characterized and peel tests performed to ensure pouch seal integrity. Accelerated shelf-life tests of ABSO(2)RB and regular MRE pouches without the O(2)-absorber were conducted for 3 mo at 51.7 degrees C (125 degrees F), and 6 mo at 37.8 degrees C (100 degrees F) by measuring oxygen concentration (Mocon O(2)-analyzer), microbiological, and physicochemical quality characteristics, including color, texture, moisture, free fatty acid (FFA), pH, water activity, and vitamins and A. Pouches stored at 26.7 degrees C (80 degrees F) for 12 mo served as calibrated controls. Consumer tests were conducted in-house and a confirmatory sensory test was conducted at Natick by a trained panel using a 9-point hedonic scale. ABSO(2)RB-laminates maintain the same seal integrity and strength as those of the control samples. The headspace oxygen concentrations in these pouches reached (P < 0.05) < 0.5% in 11 d of storage at 26.7 degrees C (80 degrees F) and remained below this level throughout the storage period (1 y). No microbial growth (aerobic, coliforms, yeast, and molds) was detected (P < 0.05) for both packages. Overall, the ABSO(2)RB-pouches indicate an improved reduction in oxygen and vitamin C retention compared with MRE controls and maintained product quality (physicochemical and organoleptic). ABSO(2)RB-laminates met the accelerated shelf-life requirement of 1 mo at 51.7 degrees C (125 degrees F), and 6 mo at 37.8 degrees C (100 degrees F). This study clearly shows the benefits of using active packaging technology on retaining nutrition and prolonging shelf life of high-fat, liquid content MRE items.


Subject(s)
Food Packaging/instrumentation , Food Preservation , Military Personnel , Oxygen/chemistry , Absorption , Ascorbic Acid/analysis , Cheese/analysis , Cheese/microbiology , Fatty Acids, Nonesterified/analysis , Food Microbiology , Humans , Oxygen/analysis , Sensation , Solutions , Time Factors , Vitamin A/analysis , Water/analysis
15.
Biol Rev Camb Philos Soc ; 84(2): 203-23, 2009 May.
Article in English | MEDLINE | ID: mdl-19391202

ABSTRACT

Plant populations are regulated by a diverse assortment of abiotic and biotic factors that influence seed dispersal and viability, and seedling establishment and growth at the microsite. Rarely does one animal guild exert as significant an influence on different plant assemblages as land crabs. We review three tropical coastal ecosystems-mangroves, island maritime forests, and mainland coastal terrestrial forests-where land crabs directly influence forest composition by limiting tree establishment and recruitment. Land crabs differentially prey on seeds, propagules and seedlings along nutrient, chemical and physical environmental gradients. In all of these ecosystems, but especially mangroves, abiotic gradients are well studied, strong and influence plant species distributions. However, we suggest that crab predation has primacy over many of these environmental factors by acting as the first limiting factor of tropical tree recruitment to drive the potential structural and compositional organisation of coastal forests. We show that the influence of crabs varies relative to tidal gradient, shoreline distance, canopy position, time, season, tree species and fruiting periodicity. Crabs also facilitate forest growth and development through such activities as excavation of burrows, creation of soil mounds, aeration of soils, removal of leaf litter into burrows and creation of carbon-rich soil microhabitats. For all three systems, land crabs influence the distribution, density and size-class structure of tree populations. Indeed, crabs are among the major drivers of tree recruitment in tropical coastal forest ecosystems, and their conservation should be included in management plans of these forests.


Subject(s)
Brachyura/physiology , Ecosystem , Trees/physiology , Tropical Climate , Animals
18.
Rev. biol. trop ; 54(1): 149-161, mar. 2006. tab, graf
Article in English | LILACS | ID: lil-484704

ABSTRACT

In Costa Rica’s Corcovado National Park, the fossorial land crab, Gecarcinus quadratus (Gecarcinidae), densely populates (1-6 m-2) a region of forest extending from the Park’s Pacific coastline inland to ca.600 m. Throughout this coastal forest (crabzone), crabs selectively forage for fallen leaves and relocate them to subterranean burrow chambers. Comparisons between surface soils (0 -15 cm) sampled from the crabzone and forest lying immediately inland that is naturally devoid of crabs (crabless zone) suggest that crabzone top soils contained less organic carbon and fewer fine and very fine roots. In contrast, soils sampled from 70 -100 cm depths in the crabzone contained twice the carbon of the crabless zone during the dry season but similar values during the wet season. Two years of experimental crab exclusion from 25 m2 replicates established in the crabzone resulted in 16% more organic carbon content in surface soils relative to baseline conditions (n.s.) and 22% more carbon than final control values (P <0.05).Excavations of burrow chambers, with an average (±SD) depth of 48 ±12 cm, indicated localized, subterranean pockets of elevated (+60 %) organic carbon and increased densities of fine and very fine roots relative to same-depth samples from the crabzone unassociated with burrows chambers.


El cangrejo Gecarcinus quadratus (Gecarcinidae) habita madrigueras terrestres y afecta el retorno de carbón orgánico a los suelos de los bosques lluviosos al reducir la acumulación de hojarasca y alterar su proceso de descomposición. En el Parque Nacional Corcovado en Costa Rica, G. quadratus vive en altas densidades (de 1-6 cangrejos m-2) en una franja boscosa que se extiende desde la costa del Océano Pacífico hasta 600 m tierra adentro. En esta región de bosque costero (‘zona cangrejera’), los cangrejos buscan alimento selectivamente en la hojarasca, trasladando lo que recolectan a sus cuevas de más de 1 m de profundidad. Comparaciones entre la superficie de los suelos de la zona cangrejera y los de la región inmediata pero más lejana a la costa y sin cangrejos (‘zona no-cangrejera’), revelan que la capa superficial del suelo (a 10 cm) en la zona cangrejera contiene 39% menos carbono orgánico, 72% menos raíces finas y 50% menos raíces muy finas. Estos resultados contrastan con muestreos similares realizados en ambas zonas en suelos de 75-100 cm de profundidad, donde se encontraron similares concentraciones de carbono orgánico, pero la zona cangrejera tenía el doble de raíces finas y más del cuádruple de raíces muy finas que en la zona no-cangrejera. Encierros experimentales de 25 m2 realizados durante 2 a no revelaron ningún efecto de manipulación en los perfiles verticales de carbono orgánico. Sin embargo, los suelos superficiales de los encierros presentaron 18 ± 8% más carbono que los valores de control. En contraste, excavaciones en los agujeros de los cangrejos de un promedio (± SD) de profundidad de 48 ± 12 centímetros revelaron concentraciones subterráneas elevadas (+60%) de carbono orgánico con densidades elevadas de raíces finas (+1500%) y de raíces muy finas (+200%), en relación con muestras tomadas a la misma profundidad en la zona cangrejera (pero no asociadas a cuevas de cangrejos).


Subject(s)
Animals , Brachyura/physiology , Carbon/metabolism , Trees , Costa Rica , Carbon/analysis
19.
Rev Biol Trop ; 54(1): 149-61, 2006 Mar.
Article in English | MEDLINE | ID: mdl-18457184

ABSTRACT

In Costa Rica's Corcovado National Park, the fossorial land crab, Gecarcinus quadratus (Gecarcinidae), densely populates (1 - 6 m(-2)) a region of forest extending from the Park's Pacific coastline inland to ca. 600 m. Throughout this coastal forest ('crabzone'), crabs selectively forage for fallen leaves and relocate them to subterranean burrow chambers. Comparisons between surface soils (0 - 15 cm) sampled from the crabzone and forest lying immediately inland that is naturally devoid of crabs ('crabless zone') suggest that crabzone top soils contained less organic carbon and fewer fine and very fine roots. In contrast, soils sampled from 70 - 100 cm depths in the crabzone contained twice the carbon of the crabless zone during the dry season but similar values during the wet season. Two years of experimental crab exclusion from 25 m2 replicates established in the crabzone resulted in 16% more organic carbon content in surface soils relative to baseline conditions (n.s.) and 22% more carbon than final control values (P < 0.05). Excavations of burrow chambers, with an average (+/- SD) depth of 48 +/- 12 cm, indicated localized, subterranean pockets of elevated (+ 60 %) organic carbon and increased densities of fine and very fine roots relative to same-depth samples from the crabzone unassociated with burrows chambers.


Subject(s)
Brachyura/physiology , Carbon/metabolism , Trees , Animals , Carbon/analysis , Costa Rica
20.
Arch Pediatr Adolesc Med ; 158(3): 244-9, 2004 Mar.
Article in English | MEDLINE | ID: mdl-14993083

ABSTRACT

BACKGROUND: In the United States, children of color, children who live in urban medically underserved communities, and children whose families have limited economic resources have excessively high rates of asthma. The identification of high-risk subgroups of underserved children is crucial for understanding the determinants and scope of the childhood asthma epidemic and for developing successful interventions. OBJECTIVE: To determine the population prevalence of asthma among homeless children. DESIGN: Cross-sectional study. SETTING: Three family shelters in New York City. PARTICIPANTS: A total of 740 children whose families entered 3 family shelters from June 30, 1998, to September 18, 1999. MAIN OUTCOME MEASURES: Prior physician asthma diagnosis, current asthma symptoms using National Asthma Education and Prevention Program symptom criteria, current medications, and emergency department use in the past year. RESULTS: Of the children, 26.9% had a prior physician diagnosis of asthma. In addition, 12.9% of the children without a prior physician diagnosis of asthma reported symptoms consistent with moderate or severe persistent asthma. Overall, 39.8% of homeless children in New York City are likely to have asthma. Few children with persistent asthma received any anti-inflammatory treatment. Almost 50% (48.6%) of children with severe persistent asthma had at least 1 emergency department visit in the past year; 24.8% of children with symptoms of mild intermittent asthma had at least 1 visit. CONCLUSIONS: The prevalence of asthma among a random sample of homeless children in New York City is likely to be 39.8%-more than 6 times the national rate for children. Asthma in homeless children is also likely to be severe and substantially undertreated.


Subject(s)
Asthma/epidemiology , Homeless Youth , Adolescent , Child , Child, Preschool , Cross-Sectional Studies , Female , Humans , Male , New York City/epidemiology , Prevalence
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