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1.
Environ Sci Technol ; 57(48): 19508-19518, 2023 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-37934657

RESUMO

The role of hydrogen in energy system decarbonization is being actively examined by the research and policy communities. We evaluate the potential "hydrogen economy" in global climate change mitigation scenarios using the Global Change Analysis Model (GCAM). We consider major hydrogen production methods in conjunction with delivery options to understand how hydrogen infrastructure affects its deployment. We also consider a rich set of hydrogen end-use technologies and vary their costs to understand how demand technologies affect deployment. We find that the availability of hydrogen transmission and distribution infrastructure primarily affects the hydrogen production mix, particularly the share produced centrally versus on-site, whereas assumptions about end-use technology primarily affect the scale of hydrogen deployment. In effect, hydrogen can be a source of distributed energy, enabled by on-site renewable electrolysis and, to a lesser extent, by on-site production at industrial facilities using natural gas with carbon capture and storage (CCS). While the share of hydrogen in final energy is small relative to the share of other major energy carriers in our scenarios, hydrogen enables decarbonization in difficult-to-electrify end uses, such as industrial high-temperature heat. Hydrogen deployment, and in turn its contribution to greenhouse gas mitigation, increases as the climate objective is tightened.


Assuntos
Gases de Efeito Estufa , Mudança Climática , Indústrias
2.
Int J Gynaecol Obstet ; 163(2): 445-452, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37635685

RESUMO

OBJECTIVE: Abnormalities of the menstrual cycle were reported after infection with SARS-CoV-2 and vaccination against it, but the available data are very heterogeneous, do not reflect intermenstrual variations or regional differences, and their risk factors are missing. METHODS: We performed a survey-based study among 6383 employees and students of Ulm University Hospital in Germany between March 1 and 31, 2021. Attributes of menstrual cycles such as cycle length (CL), menses duration (MD), and bleeding volume (BV) were reported as categorical variables before and after immunization against SARS-CoV-2 (first, second, third vaccination or infection). Additionally, the potential risk factors for cycle changes were evaluated and all participants reported the subjective perception of changes, their duration, and time of occurrence. RESULTS: The final analysis included 1726 participants. CL and BV significantly changed after vaccination, but not MD. The subjective perception showed only slight levels of agreement with the objective changes, with the highest Cohen's kappa for CL. The risk factors for the variations in CL were previous cycle irregularities, and risk factors for the changes in BV were age and body mass index. The combination of vaccines (homogenous or heterogeneous) and different types of immunization (infection and vaccination) had no significant effect on cycle irregularities. CONCLUSION: In summary, immunization against SARS-CoV-2 causes changes in the characteristics of the menstrual cycle, which are mostly temporary. The individual risk factors, but not the type of immunization, can affect the mentioned changes.


Assuntos
COVID-19 , SARS-CoV-2 , Feminino , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , Estudos Transversais , Imunização , Ciclo Menstrual , Vacinação
3.
Nat Commun ; 14(1): 3164, 2023 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-37258514

RESUMO

Although battery electric vehicles (BEVs) are climate-friendly alternatives to internal combustion engine vehicles (ICEVs), an important but often ignored fact is that the climate mitigation benefits of BEVs are usually delayed. The manufacture of BEVs is more carbon-intensive than that of ICEVs, leaving a greenhouse gas (GHG) debt to be paid back in the future use phase. Here we analyze millions of vehicle data from the Chinese market and show that the GHG break-even time (GBET) of China's BEVs ranges from zero (i.e., the production year) to over 11 years, with an average of 4.5 years. 8% of China's BEVs produced and sold between 2016 and 2018 cannot pay back their GHG debt within the eight-year battery warranty. We suggest enhancing the share of BEVs reaching the GBET by promoting the effective substitution of BEVs for ICEVs instead of the single-minded pursuit of speeding up the BEV deployment race.

4.
J Environ Manage ; 319: 115512, 2022 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-35803068

RESUMO

The expansion of road networks in emerging economies such as China causes significant greenhouse gas (GHG) emissions. This development is conflicting with China's commitment to achieve carbon neutrality. Thus, there is a need to better understand life cycle emissions of road infrastructure and opportunities to mitigate these emissions. Existing impact studies of roads in developing countries do not address recycled materials, improved pavement maintenance, or pavement-vehicle interaction and electric vehicle (EV) adoption. Combining firsthand information from Chinese road construction engineers with publicly available data, this paper estimates a comprehensive account of GHG emissions of the road pavement network to be constructed in the next ten years in the Shandong province in Northern China. Further, we estimate the potential of GHG emission reductions achievable under three scenario sets: maintenance optimization, alternative pavement material replacement, and EV adoption. Results show that the life cycle GHG emissions of highways and Class 1-4 roads to be constructed in the next 10 years amount to 147 Mt CO2-eq. Considering the use phase in our model reveals that it is the dominant stage in terms of emissions, largely due to pavement-vehicle interaction. Vehicle electrification can only moderately mitigate these emissions. Other stages, such as materials production and road maintenance and rehabilitation, contribute substantially to GHG emissions as well, highlighting the importance of optimizing the management of these stages. Surprisingly, longer, not shorter maintenance intervals, yield significant emission reductions. Another counter-intuitive finding is that thicker and more material-intensive pavement surfaces cause lower emissions overall. Taken together, optimal maintenance and rehabilitation schedules, alternative material use, and vehicle electrification provide GHG reduction potentials of 11%, 4%-16% and 2%-6%, respectively.


Assuntos
Gases de Efeito Estufa , Animais , Carbono , China , Efeito Estufa , Estágios do Ciclo de Vida , Reciclagem
5.
Nat Commun ; 12(1): 7121, 2021 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-34880225

RESUMO

Large-scale electric vehicle adoption can greatly reduce emissions from vehicle tailpipes. However, analysts have cautioned that it can come with increased indirect emissions from electricity and battery production that are not commonly regulated by transport policies. We combine integrated energy modeling and life cycle assessment to compare optimal policy scenarios that price emissions at the tailpipe only, versus both tailpipe and indirect emissions. Surprisingly, scenarios that also price indirect emissions exhibit higher, rather than reduced, sales of electric vehicles, while yielding lower cumulative tailpipe and indirect emissions. Expected technological change ensures that emissions from electricity and battery production are more than offset by reduced emissions of gasoline production. Given continued decarbonization of electricity supply, results show that a large-scale adoption of electric vehicles is able to reduce CO2 emissions through more channels than previously expected. Further, carbon pricing of stationary sources will also favor electric vehicles.

6.
Environ Sci Technol ; 55(23): 16184-16194, 2021 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-34807590

RESUMO

During the 20th century, the United States went from being the largest producer and user of lithium to being heavily reliant on imports from Asia, particularly lithium-ion batteries. To explore different futures for U.S. lithium, we here generate four scenarios─including COVID-19 implications─that model lithium use for its main applications: electric and hybrid vehicles, stationary energy storage systems, and small electronics. We find that the "Sustainable Future" scenario requires the highest amount of lithium (cumulatively 1281 Gg in the period 2020-2050, peak inflow in 2040 at 53 Gg); in contrast, "Fossil Fuel Everything" requires only 500 Gg and peaks in 2050 at 26 Gg. COVID-19 implications appear to be negligible in the long run. The future electrification of the U.S. vehicle fleet and energy storage systems will depend upon a reliable and resilient international supply chain of lithium chemicals and/or batteries as well as vigorous recycling efforts.


Assuntos
COVID-19 , Lítio , Fontes de Energia Elétrica , Eletricidade , Humanos , SARS-CoV-2 , Estados Unidos
7.
Oncology ; 99(12): 780-789, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34535596

RESUMO

INTRODUCTION: Ki67 as a proliferative marker has prognostic and therapeutic relevance in early breast cancer (EBC). However, standard cutoffs for distinguishing low and high Ki67 do not exist. MATERIAL AND METHODS: Data from all patients treated at the University Hospital Ulm for EBC between January 2013 and December 2015 with documented results for internal Ki67 assessment of the primary (n = 917) tumor were retrospectively analyzed evaluating the associations between Ki67 and other clinicopathological factors. RESULTS: 595 (64.9%) patients had a Ki67 <20% and 322 (35.1%) a Ki67 ≥20%. The median Ki67 was 10% (range 1-90%). Median Ki67 values according to the hormone receptor (HR)/ human epidermal growth factor receptor 2 (HER2) subtypes were 10% for HR-positive/HER2 negative (HR+/HER2-) disease (n = 717), 20% for HR+/HER2+ (n = 76), 30% for HR-/HER2+ (n = 45), and 60% for HR-/HER2- (n = 75). 75.2% or 89.3% of all patients with HER2-positive or triple-negative disease had a Ki67 ≥20%, respectively. Using a multivariable logistic regression with Ki67 (<20% vs. ≥20%) as binary dependent variable, younger age, positive nodal status, higher grading, histological nonspecific type carcinoma, negative HR status, and positive HER2 status were shown to be significantly associated with a higher proliferative index (Ki67 ≥20%). CONCLUSION: This analysis described Ki67 in different subtypes in EBC and its association with clinicopathological factors. According to more aggressive tumor biology, the respective subgroups also showed higher median Ki67 levels. However, definition of low and high proliferation index itself is difficult. It is essential to interpret Ki67 indices carefully with regard to the own institutional values and other clinicopathological factors.


Assuntos
Carcinoma Ductal de Mama/metabolismo , Carcinoma Lobular/metabolismo , Antígeno Ki-67/metabolismo , Receptor ErbB-2/metabolismo , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo , Neoplasias de Mama Triplo Negativas/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Carcinoma Ductal de Mama/epidemiologia , Carcinoma Ductal de Mama/patologia , Carcinoma Lobular/epidemiologia , Carcinoma Lobular/patologia , Feminino , Alemanha/epidemiologia , Hospitais Universitários , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Prognóstico , Estudos Retrospectivos , Neoplasias de Mama Triplo Negativas/epidemiologia , Neoplasias de Mama Triplo Negativas/patologia
8.
Nat Commun ; 12(1): 5097, 2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34429412

RESUMO

Material production accounts for a quarter of global greenhouse gas (GHG) emissions. Resource-efficiency and circular-economy strategies, both industry and demand-focused, promise emission reductions through reducing material use, but detailed assessments of their GHG reduction potential are lacking. We present a global-scale analysis of material efficiency for passenger vehicles and residential buildings. We estimate future changes in material flows and energy use due to increased yields, light design, material substitution, extended service life, and increased service efficiency, reuse, and recycling. Together, these strategies can reduce cumulative global GHG emissions until 2050 by 20-52 Gt CO2-eq (residential buildings) and 13-26 Gt CO2e-eq (passenger vehicles), depending on policy assumptions. Next to energy efficiency and low-carbon energy supply, material efficiency is the third pillar of deep decarbonization for these sectors. For residential buildings, wood construction and reduced floorspace show the highest potential. For passenger vehicles, it is ride sharing and car sharing.

9.
Environ Sci Technol ; 55(1): 65-72, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33327721

RESUMO

With the expected rapid growth of renewable electricity generation, charging plug-in hybrid electric vehicles (PHEVs) from the grid promise ever higher reductions in CO2 emissions. Previous analyses have found that the share that PHEVs are driven in electric mode can differ substantially depending on region, battery size, and trip purpose. Here, we provide a first fleet-wide emissions mitigation potential of US-based PHEV drivers adopting high or low shares of electric driving. Specifically, we illustrate scenarios of different combinations of PHEV uptake, renewable electricity generation shares, and PHEV fueling behavior. Across 21 analyzed scenarios, annual greenhouse gas (GHG) emissions of the light-duty vehicle (LDV) fleet could differ by an average of 21% (5-43% range) in 2050 depending alone on the fueling behavior of PHEV drivers. This behavior could further determine the discharge of about 1.3 (0.7-1.9) Gt CO2 (or roughly one year of current emissions) over the next three decades, significantly influencing the feasibility of reaching an 80% emission reduction target for the LDV sector. Governments can nudge PHEV drivers toward environmentally favorable fueling behavior. We discuss several options for nudging, including charging infrastructure availability, battery design, and consumer education.


Assuntos
Condução de Veículo , Gases de Efeito Estufa , Fontes de Energia Elétrica , Eletricidade , Veículos Automotores , Emissões de Veículos/análise
10.
Oncology ; 98(2): 91-97, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31593942

RESUMO

OBJECTIVE: At the end of the year 2018, a new FIGO classification for cervical cancer was published, mainly revising stage IB and introducing a new stage IIIC, which includes irrespectively of tumor size and local spread all patients with lymph node metastasis. METHODS: We retrospectively analyzed all cases of cervical cancer stage I to IIB who underwent surgery as primary treatment at our institution from 2000 until 2016 and therefore had a histological confirmation of tumor stage. We reclassified all histologies according to the new FIGO classification and calculated outcome according to the new stages. RESULTS: Out of 265 patients, 146 (55%) patients were reclassified into a higher FIGO stage. Most changes appeared within stage IB and from any stage to stage IIIC1. Kaplan-Meier curves for new stages showed a significant difference in disease-free survival (DFS) and overall survival (OS) between stages I versus II versus III (log-rank test, both p < 0.001). Overall, patients that were upstaged had a significant worse DFS (p = 0.012) and OS (p = 0.008) than patients whose stage did not change. Similar observations were made within sub-stages, when node-positive IB or IIB tumors were upstaged to IIIC tumors. CONCLUSION: The new FIGO classification for cervical cancer reflects the strong impact of lymph node metastases on survival and is a clear improvement compared to the old FIGO classification with regard to risk stratification.


Assuntos
Estadiamento de Neoplasias/métodos , Neoplasias do Colo do Útero/diagnóstico , Neoplasias do Colo do Útero/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Gradação de Tumores , Metástase Neoplásica , Prognóstico , Estudos Retrospectivos
11.
Arch Gynecol Obstet ; 301(1): 273-281, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31781887

RESUMO

INTRODUCTION: Large translational research projects may contribute to further progress in cancer treatment by exploring molecular biology, immunologic approaches and identification of new prognostic and predictive factors. Therefore, the BRandOBio-project combines a clinical registry for collection of patient and tumor characteristics with a biobank comprising tumor and liquid biopsies. In addition, sociodemographic, environmental and lifestyle factors of included patients with primary newly diagnosed breast or ovarian cancer, other rare malignant ovarian tumors or gestational trophoblastic disease are prospectively collected. METHODS: The target population includes the German "Alb-Allgäu-Bodensee Region" which constitutes the outreach area of the University Hospital Ulm with affiliated academic centers and private practices. Clinical data combined with primary tumor tissue samples and longitudinal repeatedly collected blood samples [before, 6 (in high-risk situations), 12, 36 and 60 months after treatment and at relapse] will be acquired from more than 4000 patients within the next years. Standardized questionnaires are given to patients of the University Hospital Ulm and eight selected external sites for assessing life style and cancer risk factors. Concomitantly, storage of paraffin-embedded tumor samples as well as liquid biopsy samples will allow translational research projects, for example in terms of investigating circulating DNA and germ line DNA from cell pellets. RESULTS: Starting in January 2016 at the University Hospital Ulm, 19 additional external sites started recruiting patients in March 2017. As of September 15th 2019, 2151 patients with newly diagnosed cancers could be recruited (2044 breast cancer; 107 ovarian cancer). Nearly all patients provided biological samples (tumor and liquid biopsy) and about 80% returned the standardized questionnaire. After 1 year follow-up, blood samples were available from more than 80% of the participating patients. CONCLUSIONS: The BRandO BIO study is a large prospective cohort study with integrated comprehensive biobank and evaluation of sociodemographic and life style factors of gynecological cancer patients in a well-defined geographical area in the South West of Germany. Continuous high patient recruitment and stable rates over 80% for returned questionnaires as well as for repeated blood sampling show high acceptance of the BRandO study program and confirms feasibility of the project.


Assuntos
Bancos de Espécimes Biológicos/normas , Neoplasias da Mama/diagnóstico , Neoplasias Ovarianas/diagnóstico , Adulto , Estudos de Viabilidade , Feminino , Humanos , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Pesquisa Translacional Biomédica
12.
Mol Oncol ; 11(11): 1508-1526, 2017 11.
Artigo em Inglês | MEDLINE | ID: mdl-28700115

RESUMO

During intravasation, circulating tumor cells (CTCs) detach from the epithelium of origin and begin the epithelial-to-mesenchymal transition (EMT) process, where they lose epithelial features and pass through the endothelium to enter circulation. Although detachment from the extracellular matrix is a strong source of metabolic stress, which induces anoikis, CTCs can survive. Recently, the tumor suppressor liver kinase B1 (LKB1) has gained attention for its role as a proto-oncogene in restoring the correct ATP/AMP ratio during metabolic stress. The aim of this study was to assess LKB1 expression in epithelial-negative CTCs isolated from patients with metastatic breast cancer and to characterize its possible association with EMT and stemness features. Transcriptome analysis of EpCAM-negative CTCs indicated that over 25% of patients showed enhanced LKB1 levels, while almost 20% of patients showed enhanced levels of an EMT transcription factor known as ZEB1. Transcriptome and immunofluorescence analyses showed that patients with enhanced LKB1 were correspondingly ZEB1 negative, suggesting complementary activity for the two proteins. Only ZEB1 was significantly associated with cancer stem cell (CSC) markers. Neither LKB1 nor ZEB1 upregulation showed a correlation with clinical outcome, while enhanced levels of stemness-associated CD44 correlated with a lower progression-free and overall survival. Ex vivo models showed that MDA-MB-231, a mesenchymal tumor cell line, grew in suspension only if LKB1 was upregulated, but the MCF-7 epithelial cell line lost its ability to generate spheroids and colonies when LKB1 was inhibited, supporting the idea that LKB1 might be necessary for CTCs to overcome the absence of the extracellular matrix during the early phases of intravasation. If these preliminary results are confirmed, LKB1 will become a novel therapeutic target for eradicating metastasis-initiating CTCs from patients with primary breast cancer.


Assuntos
Neoplasias da Mama/patologia , Regulação Neoplásica da Expressão Gênica , Invasividade Neoplásica/patologia , Células Neoplásicas Circulantes/patologia , Proteínas Serina-Treonina Quinases/genética , Quinases Proteína-Quinases Ativadas por AMP , Adulto , Idoso , Mama/metabolismo , Mama/patologia , Neoplasias da Mama/genética , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular , Transição Epitelial-Mesenquimal , Feminino , Humanos , Pessoa de Meia-Idade , Invasividade Neoplásica/genética , Células Neoplásicas Circulantes/metabolismo , Projetos Piloto , Proteínas Serina-Treonina Quinases/análise , Proteínas Serina-Treonina Quinases/metabolismo , Proto-Oncogene Mas , Estresse Fisiológico , Transcriptoma
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