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1.
Int J Biometeorol ; 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38679662

RESUMEN

Little has been studied about microclimate and the thermal comfort during the implementation of silvopastoral systems. This study aimed to evaluate the microclimate and thermal comfort during the implementation of High Biodiversity Silvopastoral System with Nuclei (SPSnu). Three treatments were investigated, SPSnu with 5 and 10% of the pasture area with nuclei, (SPSnu5 and SPSnu10, respectively), and treeless pasture (TLP). Each treatment was subdivided into 4 areas: within the nuclei, around the nuclei, around the nuclei with shade and internuclei. The analyzed variables were soil surface temperature, air temperature, wind speed, relative humidity, black globe temperature and the Heat Load Index (HLI) at 20 and 120 cm height. We hypothesized that the wind speed reduction associated with insufficient shade projection typical of the first years of SPSs may interfere in microclimate and thermal comfort during the hot seasons. SPSnu5 and SPSnu10 had a reduction in wind speed of 51.58% and 68.47% respectively when compared to TLP at 20 cm. Soil surface temperature and air temperature at 120 cm were higher for SPSnu than TLP. The same effect was observed for the HLI. At 20 cm, HLI indicated better thermal comfort in TLP than in the SPSnu treatments. The lack of shade projection from young nuclei in conjunction with the decrease of wind speed between the nuclei caused a higher air temperature and HLI in the SPSnu treatments, we called this conditions, windbreak countereffect. Farmers must knowledge this effect when implementing SPSs, and when necessary, mitigate with the proper management decisions.

2.
Int J Biometeorol ; 67(7): 1199-1212, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37278864

RESUMEN

This study aimed to assess the influence of the high biodiversity silvopastoral system (SPSnu) on the microclimate, pasture production, and pasture chemical composition. Microclimate variables and pasture production and chemical composition were measured in pared paddocks under SPSnu and treeless pasture (TLP) in a commercial farm during four seasons in Southern Brazil. SPSnu measurements were subdivided into two areas: around the nuclei (AN) and area inter-nuclei (IN). In the TLP paddocks, we plotted fictitious nuclei with the same areas and distributions of SPSnu, however without trees. For the microclimate measurements, these areas were noted when shaded or unshaded by the nuclei trees. In each season, the microclimate variables air temperature (AT, °C), relative humidity (RH, %), illuminance (Ilu, lux), wind speed (WS, m/s), and soil surface temperature (SST, °C) were measured. In addition, botanical composition (%), pasture production (kg/DM/ ha), and pasture chemical composition were evaluated. The SPSnu provided the lowest values of microclimate variables in all seasons (p < 0.05), except for the relative humidity. Winter had the highest thermal amplitude in the systems. The highest difference between SPSnu and TLP for AT (4.3 °C) and SST (5.2 °C) was measured during the hot seasons (spring and summer). In contrast, during cold seasons (autumn and winter) it observed highest thermal amplitude between SPSnu and TLP. Overall, the highest annual pasture production was observed in the SPSnu (p < 0.05). During the summer, the SPSnu areas showed the highest values of crude protein and dry matter (p < 0.05). During the winter, the TLP showed the lowest values (p < 0.05) of pasture production and dry matter. It was observed that SPSnu improved the microclimate at the pasture level, influencing pasture production and pasture chemical composition. The enhanced microclimate can partially mitigate some of the effects of climate change on pastoral agroecosystems, creating conditions for ecological rehabilitation of ecosystem processes and services. These conditions could be amplified to a biome level through a payment for ecosystem services program.


Asunto(s)
Ecosistema , Microclima , Temperatura , Frío , Árboles , Biodiversidad , Estaciones del Año , Humedad
3.
Front Cell Dev Biol ; 10: 883841, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35721490

RESUMEN

Mechanisms devoted to the secretion of proteins via extracellular vesicles (EVs) have been found in mammals, yeasts, and plants. Since they transport a number of leader-less proteins to the plasma membrane or the extracellular space, EVs are considered part of Unconventional protein secretion (UPS) routes. UPS involving EVs are a relatively new field in plants. Aside from their role in plant physiology and immunity, plant extracts containing EVs have also been shown to be beneficial for human health. Therefore, exploring the use of plant EVs in biomedicine and their potential as drug delivery tools is an exciting avenue. Here we give a summary of the state of knowledge on plant EVs, their crosstalk with mammalian systems and potential research routes that could lead to practical applications in therapeutic drug delivery.

4.
Br J Nurs ; 31(7): S22-S26, 2022 Apr 07.
Artículo en Inglés | MEDLINE | ID: mdl-35404661

RESUMEN

BACKGROUND: Percutaneous endoscopic gastrostomy (PEG) tubes are removed and/or replaced for reasons such as tube malfunction, degradation, patient's device preference, and when stopping enteral feeding. AIMS: To identify the types and rate of complications associated with traction removal of a PEG tube and if this is associated with the size of the PEG or length of time it had been in situ prior to removal. METHODS: This retrospective study looked at the tube removal/replacement reports written by the Enteral Feeding Nursing Service over an 8-year period at a large teaching hospital trust in the north of England. FINDINGS: The PEG tube removal reports of 127 patients were reviewed. Five types of complication were identified, categorised as retained bumper (5.5%); intraperitoneal placement of new device (3.17%); misplacement of replacement device into colon (a consequence of the insertion procedure not the removal of the PEG) (0.78%): gastrocutaneous fistula (0.78%); and inability to remove the tube (1.57%). The complication of retained bumpers was associated with an average length of time in situ prior to removal of the PEG tube of 29 months. In the cases of intraperitoneal placement, the PEG tube had been in situ for an average of 6 months. Nurses were unable to remove the PEG tube on two occasions; each had been in situ for approximately 4 years prior to attempted removal. CONCLUSION: the complication rates are low following removal of a PEG tube using a traction pull. There was no clear correlation between length of time in situ or tube size and complication rate.


Asunto(s)
Gastrostomía , Tracción , Remoción de Dispositivos/efectos adversos , Nutrición Enteral , Gastrostomía/efectos adversos , Gastrostomía/métodos , Humanos , Estudios Retrospectivos
5.
Methods Mol Biol ; 2168: 3-49, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-33582985

RESUMEN

A major obstacle to studying membrane proteins by biophysical techniques is the difficulty in producing sufficient amounts of materials for functional and structural studies. To overexpress the target membrane protein heterologously, especially an eukaryotic protein, a key step is to find the optimal host expression system and perform subsequent expression optimization. In this chapter, we describe protocols for screening membrane protein production using bacterial and insect cells, solubilization screening, large-scale production, and commonly used affinity chromatography purification methods. We discuss general optimization conditions, such as promoters and tags, and describe current techniques that can be used in any laboratory without specialized expensive equipment. Especially for insect cells, GFP fusions are particularly useful for localization and in-gel fluorescence detection of the proteins on SDS-PAGE. We give detailed protocols that can be used to screen the best expression and purification conditions for membrane protein study.


Asunto(s)
Cromatografía de Afinidad/métodos , Escherichia coli/metabolismo , Proteínas Fluorescentes Verdes/metabolismo , Proteínas de la Membrana/aislamiento & purificación , Proteínas de la Membrana/metabolismo , Animales , Escherichia coli/crecimiento & desarrollo , Vectores Genéticos , Humanos , Células Sf9
6.
Int J Biometeorol ; 63(1): 83-92, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30456653

RESUMEN

The aim of this work was to evaluate the influence of high biodiversity silvopastoral system (SPSnuclei) on microclimate and thermal comfort index thru a parallel with treeless pasture (TLP) during the four seasons of the year. Three conditions were determined for this study: shadowing area in SPSnuclei, sunny area in SPSnuclei, and sunny area in TLP. During two consecutive days in each season, the following microclimatic variables were collected: air temperature (°C), relative humidity (%), illuminance (lux), wind speed (m/s), and soil surface temperature (°C). The temperature and humidity index (THI) was calculated for each condition as indicative of thermal comfort. An influence analysis was carried out by generalized linear models to evaluate the system effects on the microclimatic variables. A confirmatory analysis was done with Wilcoxon-Mann-Whitney. Systems (SPSnuclei x TLP) influenced the microclimatic variables and THI (p < 0.05). The lowest means of air temperature, illuminance, wind speed, and soil surface temperature were found in SPSnuclei. As expected, autumn and winter presented a comfortable environment even on treeless pastureland. Only the SPSnuclei showed a comfortable environment for dairy production during spring. During summer, the TLP had a microclimate and thermal comfort index not suitable for dairy production already in the first hours of the day (THI between 79 and 85). We concluded that SPSnuclei provided better environment for pasture-based dairy production when compared to TLP. The high THI measured in TLP during summer could be a limiting factor on animal production.


Asunto(s)
Biodiversidad , Industria Lechera , Granjas , Microclima , Temperatura , Animales , Brasil , Bovinos , Humedad , Estaciones del Año , Sensación Térmica , Viento
7.
Behav Brain Sci ; 39: e97, 2016 01.
Artículo en Inglés | MEDLINE | ID: mdl-27562419

RESUMEN

Ultrasociality, as expressed in agricultural, monetary, and fossil fuel economies, has spurred exponential growth in population and in resource use that now threaten civilization. These threats take the form of prisoner's dilemmas. Avoiding collapse requires more cooperative economic organization that must be informed by knowledge of human behavior and cultural evolution. The evolution of a cooperative information economy is one possibility.


Asunto(s)
Agricultura , Evolución Biológica , Evolución Cultural , Humanos
8.
J Environ Manage ; 183(Pt 2): 389-398, 2016 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-27480914

RESUMEN

The economic process transforms raw materials and energy into economic products and waste. On a finite planet, continued economic growth threatens to surpass critical socio-ecological thresholds and undermine ecosystem services upon which humans and all other species depend. For most systems, whether such thresholds exist, where they lie and whether they are reversible cannot be known with certainty until they are crossed. We argue that our central economic challenge is to maintain the resilience of the current socio-ecological regime. We must reduce net impacts of economic activity to avoid critical ecological thresholds while ensuring economic necessities. Conventional economists pursue continuous growth as the central goal of economic activity, and assume that the price mechanism and technological breakthroughs ensure system resilience. Unfortunately, the price mechanism fails to address ecological thresholds because it ignores unowned ecosystem services, and fails to address economic thresholds because it ignores the needs of the poorest individuals, who live on the edge of them. Panarchy theory suggests that systems go through a cycle of growth, conservation, release and renewal. Managing a subsystem too long for growth or conservation-which many consider to be the goal of sustainability-actually threatens to collapse the higher-level system upon which that subsystem depends. Black Swan theory suggests we should seek to reduce the risk of catastrophic thresholds and promote the likelihood of technological breakthroughs. Economic degrowth, or planned release, is required to avoid catastrophic collapse. At the same time, publicly funded, open source information can help stimulate the technological breakthroughs economists count on to ensure resilience.


Asunto(s)
Conservación de los Recursos Naturales/economía , Ecosistema , Modelos Teóricos , Animales , Comercio , Ecología/economía , Humanos , Invenciones , Factores Socioeconómicos
9.
Conserv Biol ; 27(6): 1286-93, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24112105

RESUMEN

Measures aimed at conservation or restoration of ecosystems are often seen as net-cost projects by governments and businesses because they are based on incomplete and often faulty cost-benefit analyses. After screening over 200 studies, we examined the costs (94 studies) and benefits (225 studies) of ecosystem restoration projects that had sufficient reliable data in 9 different biomes ranging from coral reefs to tropical forests. Costs included capital investment and maintenance of the restoration project, and benefits were based on the monetary value of the total bundle of ecosystem services provided by the restored ecosystem. Assuming restoration is always imperfect and benefits attain only 75% of the maximum value of the reference systems over 20 years, we calculated the net present value at the social discount rates of 2% and 8%. We also conducted 2 threshold cum sensitivity analyses. Benefit-cost ratios ranged from about 0.05:1 (coral reefs and coastal systems, worst-case scenario) to as much as 35:1 (grasslands, best-case scenario). Our results provide only partial estimates of benefits at one point in time and reflect the lower limit of the welfare benefits of ecosystem restoration because both scarcity of and demand for ecosystem services is increasing and new benefits of natural ecosystems and biological diversity are being discovered. Nonetheless, when accounting for even the incomplete range of known benefits through the use of static estimates that fail to capture rising values, the majority of the restoration projects we analyzed provided net benefits and should be considered not only as profitable but also as high-yielding investments. Beneficios de Invertir en la Restauración de Ecosistemas.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Arrecifes de Coral , Análisis Costo-Beneficio , Océanos y Mares , Ríos , Árboles , Humedales
10.
Ambio ; 42(2): 188-200, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23475655

RESUMEN

Forest landscapes provide benefits from a wide range of goods, function and intangible values. But what are different forest owner categories' profiles of economic use and non-use values? This study focuses on the complex forest ownership pattern of the River Helge å catchment including the Kristianstad Vattenrike Biosphere Reserve in southern Sweden. We made 89 telephone interviews with informants representing the four main forest owner categories. Our mapping included consumptive and non-consumptive direct use values, indirect use values, and non-use values such as natural and cultural heritage. While the value profiles of non-industrial forest land owners and municipalities included all value categories, the forest companies focused on wood production, and the Swedish Environmental Protection Agency on nature protection. We discuss the challenges of communicating different forest owners' economic value profiles among stakeholders, the need for a broader suite of forest management systems, and fora for collaborative planning.


Asunto(s)
Agricultura Forestal/economía , Propiedad , Ciudades , Conservación de los Recursos Naturales , Entrevistas como Asunto , Suecia
11.
Ann N Y Acad Sci ; 1185: 225-36, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20146772

RESUMEN

The world's large and rapidly growing human population is exhausting Earth's natural capital at ever-faster rates, and yet appears mostly oblivious to the fact that these resources are limited. This is dangerous for our well-being and perhaps for our survival, as documented by numerous studies over many years. Why are we not moving instead toward sustainable levels of use? We argue here that this disconnection between our knowledge and our actions is largely caused by three "great divides": an ideological divide between economists and ecologists; an economic development divide between the rich and the poor; and an information divide, which obstructs communications between scientists, public opinion, and policy makers. These divides prevent our economies from responding effectively to urgent signals of environmental and ecological stress. The restoration of natural capital (RNC) can be an important strategy in bridging all of these divides. RNC projects and programs make explicit the multiple and mutually reinforcing linkages between environmental and economic well-being, while opening up a promising policy road in the search for a sustainable and desirable future for global society. The bridge-building capacity of RNC derives from its double focus: on the ecological restoration of degraded, overexploited natural ecosystems, and on the full socio-economic and ecological interface between people and their environments.


Asunto(s)
Conservación de los Recursos Naturales/métodos , Humanismo , Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/tendencias , Ecología , Ecosistema , Humanos , Política , Población , Pobreza , Política Pública , Factores Socioeconómicos , Estados Unidos
12.
Environ Manage ; 45(1): 39-51, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19830480

RESUMEN

Humans are rapidly depleting critical ecosystems and the life support functions they provide, increasing the urgency of developing effective conservation tools. Using a case study of the conversion of mangrove ecosystems to shrimp aquaculture, this article describes an effort to develop a transdisciplinary, transinstitutional approach to conservation that simultaneously trains future generations of environmental problem solvers. We worked in close collaboration with academics, non-government organizations, local government and local communities to organize a workshop in Puerto Princesa, Palawan, Philippines. The primary objectives of the workshop were to: (1) train participants in the basic principles of ecological economics and its goals of sustainable scale, just distribution and efficient allocation; (2) learn from local community stakeholders and participating scientists about the problems surrounding conversion of mangrove ecosystems to shrimp aquaculture; (3) draw on the skills and knowledge of all participants to develop potential solutions to the problem; and (4) communicate results to those with the power and authority to act on them. We found that the economic and ecological benefits of intact mangroves outweigh the returns to aquaculture. Perversely, however, private property rights to mangrove ecosystems favor inefficient, unjust and unsustainable allocation of the resource-a tragedy of the non-commons. We presented the workshop results to the press and local government, which shut down the aquaculture ponds to conserve the threatened ecosystem. Effective communication to appropriate audiences was essential for transforming research into action. Our approach is promising and can be readily applied to conservation research and advocacy projects worldwide, but should be improved through adaptive management-practitioners must continually build on those elements that work and discard or improve those that fail.


Asunto(s)
Acuicultura , Conservación de los Recursos Naturales/métodos , Ecosistema , Comunicación Interdisciplinaria , Animales , Participación de la Comunidad , Conservación de los Recursos Naturales/economía , Educación , Humanos , Penaeidae/crecimiento & desarrollo , Filipinas , Proyectos Piloto
13.
Environ Manage ; 45(1): 26-38, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-19224276

RESUMEN

Although conservation is an inherently transdisciplinary issue, there is much to be gained from examining the problem through an economics lens. Three benefits of such an approach are laid out in this paper. First, many of the drivers of environmental degradation are economic in origin, and the better we understand them, the better we can conserve ecosystems by reducing degradation. Second, economics offers us a when-to-stop rule, which is equivalent to a when-to-conserve rule. All economic production is based on the transformation of raw materials provided by nature. As the economic system grows in physical size, it necessarily displaces and degrades ecosystems. The marginal benefits of economic growth are diminishing, and the marginal costs of ecological degradation are increasing. Conceptually, we should stop economic growth and focus on conservation when the two are equal. Third, economics can help us understand how to efficiently and justly allocate resources toward conservation, and this paper lays out some basic principles for doing so. Unfortunately, the field of economics is dominated by neoclassical economics, which builds an analytical framework based on questionable assumptions and takes an excessively disciplinary and formalistic approach. Conservation is a complex problem, and analysis from individual disciplinary lenses can make important contributions to conservation only when the resulting insights are synthesized into a coherent vision of the whole. Fortunately, there are a number of emerging transdisciplines, such as ecological economics and environmental management, that are dedicated to this task.


Asunto(s)
Conservación de los Recursos Naturales/economía , Conservación de los Recursos Naturales/métodos , Asignación de Costos , Ecología/economía , Ecología/métodos , Ecosistema , Contaminación Ambiental/economía , Humanos , Comunicación Interdisciplinaria
14.
Proc Natl Acad Sci U S A ; 106(8): 2483-9, 2009 Feb 24.
Artículo en Inglés | MEDLINE | ID: mdl-19240221

RESUMEN

A high and sustainable quality of life is a central goal for humanity. Our current socio-ecological regime and its set of interconnected worldviews, institutions, and technologies all support the goal of unlimited growth of material production and consumption as a proxy for quality of life. However, abundant evidence shows that, beyond a certain threshold, further material growth no longer significantly contributes to improvement in quality of life. Not only does further material growth not meet humanity's central goal, there is mounting evidence that it creates significant roadblocks to sustainability through increasing resource constraints (i.e., peak oil, water limitations) and sink constraints (i.e., climate disruption). Overcoming these roadblocks and creating a sustainable and desirable future will require an integrated, systems level redesign of our socio-ecological regime focused explicitly and directly on the goal of sustainable quality of life rather than the proxy of unlimited material growth. This transition, like all cultural transitions, will occur through an evolutionary process, but one that we, to a certain extent, can control and direct. We suggest an integrated set of worldviews, institutions, and technologies to stimulate and seed this evolutionary redesign of the current socio-ecological regime to achieve global sustainability.


Asunto(s)
Evolución Biológica , Conservación de los Recursos Naturales , Ecología , Humanos , Calidad de Vida
15.
Conserv Biol ; 22(6): 1399-408, 2008 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19076873

RESUMEN

Until recent decades, economic decision makers have largely ignored the nonmarket benefits provided by nature, resulting in unprecedented threats to ecological life-support functions. The economic challenge today is to decide how much ecosystem structure can be converted to economic production and how much must be conserved to provide essential ecosystem services. Many economists and a growing number of life scientists hope to address this challenge by estimating the marginal value of environmental benefits and then using this information to make economic decisions. I assessed this approach first by examining the role and effectiveness of the price mechanism in a well-functioning market economy, second by identifying the issues that prevent markets from pricing many ecological benefits, and third by focusing on problems inherent to valuing services generated by complex and poorly understood ecosystems subject to irreversible change. I then focus on critical natural capital (CNC), which generates benefits that are essential to human welfare and have few if any substitutes. When imminent ecological thresholds threaten CNC, conservation is essential and marginal valuation becomes inappropriate. Once conservation needs have been met, remaining ecosystem structure is potentially available for economic production. Demand for this available supply will determine prices. In other words, conservation needs should be price determining, not price determined. Conservation science must help identify CNC and the quantity and quality of ecosystem structure required to ensure its sustained provision.


Asunto(s)
Comercio/economía , Conservación de los Recursos Naturales/economía , Economía , Ecosistema , Modelos Econométricos
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