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1.
Waste Manag Res ; 42(10): 860-872, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39068519

RESUMO

Numbers do matter; the Intergovernmental Panel on Climate Change (IPCC)'s 2010 data that the waste sector is responsible for just 3% of global greenhouse gas (GHG) emissions has led to the misperception that solid waste management (SWM) has little to contribute to climate mitigation. Global efforts to control methane emissions and divert organic waste from landfills had already reduced direct emissions. But end-of-pipe SWM has also been evolving into more circular waste and resource management, with indirect GHG savings from the 3Rs (reduce, reuse, recycle) which IPCC accounts for elsewhere in the economy. The evidence compiled here on both direct emissions and indirect savings demonstrates with high confidence that better waste and resource management can make a significant contribution to climate mitigation, and must form a core part of every country's nationally determined contribution. Even the most advanced countries can still achieve much from the 3Rs. In the Global South, the challenge of extending waste collection to all and stopping open dumping and burning (sustainable development goal 11.6.1), essential to improve public health, can be turned into a huge opportunity. Moving early to divert waste from landfill by separation at source and collecting clean organic and dry recycling fractions, will mitigate global GHG emissions, slash ocean plastics and create decent livelihoods. But this can only happen with targeted climate, plastics and extended producer responsibility finance; and help to local communities to help themselves.


Assuntos
Mudança Climática , Gases de Efeito Estufa , Gerenciamento de Resíduos , Gerenciamento de Resíduos/métodos , Gases de Efeito Estufa/análise , Eliminação de Resíduos/métodos , Resíduos Sólidos/análise , Reciclagem/métodos , Instalações de Eliminação de Resíduos
2.
Sensors (Basel) ; 19(3)2019 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-30704095

RESUMO

The estimation of the reliability of magnetic field sensors against failure is a critical point concerning their application for industrial purposes. Due to the physical stochastic nature of the failure events, this can only be done by means of a statistical approach which is extremely time consuming and prevents a continuous observation of the production. Here, we present a novel microstructure design for a parallel measurement of the lifetime characteristics of a sensor population. By making use of two alternative designs and the Weibull statistical distribution function, we are able to measure the lifetime characteristics of a CoFeB/MgO/CoFeB tunneling junction population. The main parameters governing the time evolution of the failure rate are estimated and discussed and the suitability of the microstructure for highly reliable sensor application is proven.

3.
J Neurophysiol ; 118(3): 1650-1663, 2017 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-28659463

RESUMO

In the natural world, self-motion always stimulates several different sensory modalities. Here we investigated the interplay between a visual optic flow stimulus simulating self-motion and a tactile stimulus (air flow resulting from self-motion) while human observers were engaged in a distance reproduction task. We found that adding congruent tactile information (i.e., speed of the air flow and speed of visual motion are directly proportional) to the visual information significantly improves the precision of the actively reproduced distances. This improvement, however, was smaller than predicted for an optimal integration of visual and tactile information. In contrast, incongruent tactile information (i.e., speed of the air flow and speed of visual motion are inversely proportional) did not improve subjects' precision indicating that incongruent tactile information and visual information were not integrated. One possible interpretation of the results is a link to properties of neurons in the ventral intraparietal area that have been shown to have spatially and action-congruent receptive fields for visual and tactile stimuli.NEW & NOTEWORTHY This study shows that tactile and visual information can be integrated to improve the estimates of the parameters of self-motion. This, however, happens only if the two sources of information are congruent-as they are in a natural environment. In contrast, an incongruent tactile stimulus is still used as a source of information about self-motion but it is not integrated with visual information.


Assuntos
Percepção de Movimento , Percepção do Tato , Adulto , Feminino , Humanos , Masculino , Movimento , Lobo Parietal/fisiologia
4.
J Neurosci ; 34(33): 10892-905, 2014 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-25122891

RESUMO

Dendritic NMDA spike/plateau potentials, first discovered in cortical pyramidal neurons, provide supralinear integration of synaptic inputs on thin and distal dendrites, thereby increasing the impact of these inputs on the soma. The more specific functional role of these potentials has been difficult to clarify, partly due to the complex circuitry of cortical neurons. Thalamocortical (TC) neurons in the dorsal lateral geniculate nucleus participate in simpler circuits. They receive their primary afferent input from retina and send their output to visual cortex. Cortex, in turn, regulates this output through massive feedback to distal dendrites of the TC neurons. The TC neurons can operate in two modes related to behavioral states: burst mode prevailing during sleep, when T-type calcium bursts largely disrupt the transfer of signals from retina to cortex, and tonic mode, which provides reliable transfer of retinal signals to cortex during wakefulness. We studied dendritic potentials in TC neurons with combined two-photon calcium imaging and whole-cell recording of responses to local dendritic glutamate iontophoresis in acute brain slices from mice. We found that NMDA spike/plateaus can be elicited locally at distal dendrites of TC neurons. We suggest that these dendritic potentials have important functions in the cortical regulation of thalamocortical transmission. NMDA spike/plateaus can induce shifts in the functional mode from burst to tonic by blockade of T-type calcium conductances. Moreover, in tonic mode, they can facilitate the transfer of retinal signals to cortex by depolarization of TC neurons.


Assuntos
Potenciais de Ação/fisiologia , Córtex Cerebral/fisiologia , Dendritos/fisiologia , Neurônios/fisiologia , Tálamo/fisiologia , Potenciais de Ação/efeitos dos fármacos , Animais , Córtex Cerebral/efeitos dos fármacos , Dendritos/efeitos dos fármacos , Antagonistas de Aminoácidos Excitatórios/farmacologia , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Feminino , Ácido Glutâmico/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Vias Neurais/efeitos dos fármacos , Vias Neurais/fisiologia , Neurônios/efeitos dos fármacos , Piperazinas/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Tálamo/efeitos dos fármacos
5.
Appl Opt ; 54(16): 4966-71, 2015 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-26192652

RESUMO

In the visible to infrared spectral range, highly-reflective silver mirrors are applied in the manufacture of optical instruments such as telescopes. However, it is still difficult to combine high reflectivity and long-term stability of the protected silver coating. We show that the deposition of impervious protective layers is necessary but often not sufficient for long-term environmental stability. Hygroscopic air borne particles absorbed by the protections surface attract water molecules and form a solution. This solution first damages the protection, subsequently permeates the protection and finally damages the silver whereby the reflectivity is reduced. We demonstrate this particular damage mechanism with different experiments and describe this mechanism in detail.

6.
Int J Mol Sci ; 13(10): 12367-82, 2012 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-23202903

RESUMO

The process of radiationless energy transfer from a chromophore in an excited electronic state (the "donor") to another chromophore (an "acceptor"), in which the energy released by the donor effects an electronic transition, is known as "Förster Resonance Energy Transfer" (FRET). The rate of energy transfer is dependent on the sixth power of the distance between donor and acceptor. Determining FRET efficiencies is tantamount to measuring distances between molecules. A new method is proposed for determining FRET efficiencies rapidly, quantitatively, and non-destructively on ensembles containing donor acceptor pairs: at wavelengths suitable for mutually exclusive excitations of donors and acceptors, two laser beams are intensity-modulated in rectangular patterns at duty cycle ½ and frequencies ƒ(1) and ƒ(2) by electro-optic modulators. In an ensemble exposed to these laser beams, the donor excitation is modulated at ƒ(1), and the acceptor excitation, and therefore the degree of saturation of the excited electronic state of the acceptors, is modulated at ƒ(2). Since the ensemble contains donor acceptor pairs engaged in FRET, the released donor fluorescence is modulated not only at ƒ(1) but also at the beat frequency Δƒ: = |ƒ(1) - ƒ(2)|. The depth of the latter modulation, detectable via a lock-in amplifier, quantitatively indicates the FRET efficiency.


Assuntos
Transferência Ressonante de Energia de Fluorescência , Lasers , Microscopia Eletrônica de Varredura , Modelos Teóricos
7.
JNCI Cancer Spectr ; 4(6): pkaa097, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33409460

RESUMO

BACKGROUND: Our aim was to investigate the role of melanoma subtype on survival and focus on the effects stratified by Breslow thickness and ulceration status. METHODS: Patients with cutaneous melanoma stage I, II, or III diagnosed between 2000 and 2014 were derived from the Dutch Nationwide Pathology Registry and overall survival data from the Netherlands Cancer Registry. Patients were followed until 2018. Using multivariable Cox proportional hazards models, hazard ratios were calculated for each melanoma subtype, per Breslow thickness category and ulceration status, and adjusted for age, sex, stage, and localization. RESULTS: A total of 48 361 patients were included: 79.3% had superficial spreading melanoma (SSM), 14.6% nodular melanoma (NM), 5.2% lentigo maligna melanoma, and 0.9% acral lentiginous melanoma (ALM). In the total patient group, using SSM as the reference category, adjusted hazard ratios were 1.06 (95% confidence interval [CI] = 1.01 to 1.12) for NM, 1.02 (95% CI = 0.93 to 1.13) for lentigo maligna melanoma, and 1.26 (95% = CI 1.06 to 1.50) for ALM. Among patients with 1.0 mm or less Breslow thickness and no ulceration, NM showed a twofold increased risk (hazard ratio = 1.96, 95% CI = 1.58 to 2.45) compared with SSM. Compared with 1.0 mm or less SSM without ulceration, the hazard ratio for 1.0 mm or less SSM with ulceration was 1.94 (95% CI = 1.55 to 2.44), and the hazard ratio for 1.0 mm or less NM with ulceration was 3.46 (95% CI = 2.17 to 5.50). NM patients with tumors greater than 1.0 mm did not show worse survival than SSM patients with tumors greater than 1.0 mm. CONCLUSIONS: In this large nationwide study, ALM patients showed worse survival than SSM patients. Among patients with melanomas that were thin (1.0 mm or less), NM subtype patients also showed worse survival than SSM patients.

8.
Radiother Oncol ; 118(2): 399-407, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26700601

RESUMO

BACKGROUND: While surgery remains the cornerstone of rectal cancer treatment, organ-preservation is upcoming. Therefore, neo-adjuvant treatment should be optimized. By escalating doses, response can be increased. To limit toxicity of boost, accurate gross tumor volume (GTV) definition is required. MRI, especially undeformed fast spin echo diffusion-weighted MRI (DWI), looks promising for delineation. However, inconsistencies between observers should be quantified before clinical implementation. We aim to find which MRI sequence (T2w, DWI or combination) is optimal and clinically useful for GTV definition by evaluating inter-observer agreement. METHODS: Locally advanced rectal cancer patients (tumors <10 cm from anal verge) were scanned on 3T MRI transverse T2w and DWI (b=800 s/mm(2)). Three independent observers delineated T2w, DWI and combination (Combi) after training-set. Volumes, conformity index (CI), and maximum Hausdorff distance (HD) were calculated between any observer-pair per patient per modality. RESULTS: Twenty-four consecutive patients were included. One patient had cT2 (4.2%), 19 cT3 (79.1%) and 4 cT4 (16.7%), with 2 clinical node negative (8.3%), 4 cN1 (16.7%), and 18 cN2 (75.0%) on MRI. From 24 patients, 70 sequences were available (24x T2, 23x DWI, and 23x Combi). Between observers, no significant volume differences were observed per modality. T2 showed significantly largest volumes compared to DWI (mean difference 19.85 ml, SD 17.42, p<0.0001) and Combi (mean difference 7.16 ml, SD 11.58, p<0.0001). Mean CI was 0.70, 0.71 and 0.69 for T2, DWI and Combi respectively (p>0.61). Average HD was largest on T2 (18.60mm, max 31.40 mm, min 9.20mm). DISCUSSION: Delineation on DWI resulted in delineation of the smallest volumes with similar consistency and mean distances, but with slightly lower Hausdorff distances compared to T2 and Combi. However, with lack of a gold standard it remains difficult to establish if delineations also represent true tumor. Study strengths were DWI adaptation to exclude geometrical distortions and training-set. DWI shows great potential for delineation purposes as long as sufficient experience exists and geometrical distortions are eliminated.


Assuntos
Planejamento da Radioterapia Assistida por Computador/métodos , Neoplasias Retais/patologia , Neoplasias Retais/radioterapia , Adulto , Idoso , Idoso de 80 Anos ou mais , Imagem de Difusão por Ressonância Magnética/métodos , Estudos de Viabilidade , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Terapia Neoadjuvante/métodos , Estadiamento de Neoplasias , Variações Dependentes do Observador , Planejamento da Radioterapia Assistida por Computador/normas , Radioterapia Adjuvante/métodos , Neoplasias Retais/cirurgia
9.
Waste Manag ; 32(11): 2018-28, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22770806

RESUMO

The integration of the informal sector into municipal solid waste management is a challenge many developing countries face. In Iloilo City, Philippines around 220 tons of municipal solid waste are collected every day and disposed at a 10 ha large dumpsite. In order to improve the local waste management system the Local Government decided to develop a new Waste Management Center with integrated landfill. However, the proposed area is adjacent to the presently used dumpsite where more than 300 waste pickers dwell and depend on waste picking as their source of livelihood. The Local Government recognized the hidden threat imposed by the waste picker's presence for this development project and proposed various measures to integrate the informal sector into the municipal solid waste management (MSWM) program. As a key intervention a Waste Workers Association, called USWAG Calahunan Livelihood Association Inc. (UCLA) was initiated and registered as a formal business enterprise in May 2009. Up to date, UCLA counts 240 members who commit to follow certain rules and to work within a team that jointly recovers wasted materials. As a cooperative they are empowered to explore new livelihood options such as the recovery of Alternative Fuels for commercial (cement industry) and household use, production of compost and making of handicrafts out of used packages. These activities do not only provide alternative livelihood for them but also lessen the generation of leachate and Greenhouse Gases (GHG) emissions from waste disposal, whereby the life time of the proposed new sanitary landfill can be extended likewise.


Assuntos
Emprego , Eliminação de Resíduos/métodos , Síndrome da Imunodeficiência Adquirida/prevenção & controle , Cidades , Conservação dos Recursos Naturais , Programas Governamentais , Humanos , Malária/prevenção & controle , Filipinas , Pobreza , Reciclagem
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