824 research outputs found
An in situ assessment of local adaptation in a calcifying polychaete from a shallow CO 2 vent system
Ocean acidification (OA) is likely to exert selective pressure on natural populations. Our ability to predict which marine species will adapt to OA and what underlies this adaptive potential is of high conservation and resource management priority. Using a naturally low-pH vent site in the Mediterranean Sea (Castello Aragonese, Ischia) mirroring projected future OA conditions, we carried out a reciprocal transplant experiment to investigate the relative importance of phenotypic plasticity and local adaptation in two populations of the sessile, calcifying polychaete Simplaria sp. (Annelida, Serpulidae, Spirorbinae): one residing in low pH and the other from a nearby ambient (i.e. high) pH site. We measured a suite of fitness-related traits (i.e. survival, reproductive output, maturation, population growth) and tube growth rates in laboratory-bred F2 generation individuals from both populations reciprocally transplanted back into both ambient and low-pH in situ habitats. Both populations showed lower expression in all traits, but increased tube growth rates, when exposed to low-pH compared with high-pH conditions, regardless of their site of origin suggesting that local adaptation to low-pH conditions has not occurred. We also found comparable levels of plasticity in the two populations investigated, suggesting no influence of long-term exposure to low pH on the ability of populations to adjust their phenotype. Despite high variation in trait values among sites and the relatively extreme conditions at the low pH site (pH < 7.36), response trends were consistent across traits. Hence, our data suggest that, for Simplaria and possibly other calcifiers, neither local adaptations nor sufficient phenotypic plasticity levels appear to suffice in order to compensate for the negative impacts of OA on long-term survival. Our work also emphasizes the utility of field experiments in natural environments subjected to high level of pCO2 for elucidating the potential for adaptation to future scenarios of OA
Long-Range Low-Power Soil Water Content Monitoring System for Precision Agriculture
World population growth and desertification are increasing the food demand. Food production must increase to ensure food security in the following years. Smart agriculture tries to improve food production thanks to the adoption of electronic sensors to monitor and control fruit and vegetable crops. Another critical point in agriculture is the use of potable water. Precision irrigation strategies can be implemented to reduce water waste and increase crop production. This paper proposes a long-range, low-power sensor node to monitor soil water content. It is possible to place multiple sensor nodes in the field and use the gathered data to determine the most suitable irrigation strategy. The node communicates thanks to the LoRa protocol and it can also be used in remote areas where it is impossible to have an internet connection
Correlação da emissão diária de metano entérico e características de crescimento e eficiência alimentar de bovinos Nelore.
O objetivo deste trabalho foi avaliar as correlações entre a emissão diária de metano entérico (CH4) e características de crescimento e eficiência alimentar em bovinos Nelore com um ano de idade, previamente avaliados para o consumo alimentar residual (CAR). Foram testados 118 bovinos (56 fêmeas e 62 machos) nascidos em 2010, pertencentes à 30a progênie do rebanho Nelore Tradicional, provenientes do Centro APTA Bovinos de Corte-IZ/SP. O CAR foi estimado como o resíduo da equação de regressão do consumo de matéria seca sobre o peso metabólico e o ganho médio diário em teste pós-desmama de 107 e 112 dias de duração, para machos e fêmeas, respectivamente. Após o teste de desempenho, 46 animais (23 machos e 23 fêmeas) representativos das classes de alto CAR (>média + 0,5 DP; n= 23) e baixo CAR (<média ? 0,5 DP; n= 23), foram utilizados para estimar CH4 por meio da metodologia do gás traçador hexafluoreto de enxofre (SF6) com 7 dias Consecutivos de coleta. A emissão diária de metano está diretamente relacionada ao ganho médio diário e ao consumo de matéria seca. Não há evidências que a emissão diária de metano desses animais tenha relação com o consumo alimentar residual e a conversão alimentar
Analysis of in Vivo Plant Stem Impedance Variations in Relation with External Conditions Daily Cycle
World population growth and desertification are the most severe issue to agricultural food production. Smart agriculture is a promising solution to ensure food security. The use of sensors to monitor crop production can help farmers improve the yield and reduce water consumption. Here we propose a study where the electrical impedance of green plants' stem is analyzed in vivo, along with environmental conditions. In particular, the variations associated with the daily cycle are highlighted. These analyses lead to the possibility of understanding plant status directly from stem impedance
Live Wire - A Low-Complexity Body Channel Communication System for Landmark Identification
This paper presents a robust simplex Body Channel Communication (BCC) system aimed at providing an interactive infrastructure solution for visually impaired people. Compared to existing BCC solutions, it provides high versatility, weara- bility and installability in an environment in a low complexity hardware-software solution. It operates with a ground referred transmitter (TX) and it is based on an asynchronous thresh- old receiver (RX) architecture. Synchronization, demodulation and packetizing and threshold control are completely software defined and implemented using MicroPython. The RX includes Bluetooth® (BT) radio connectivity and a cell-phone application provides push text-to-speech notifications to a smartphone. The hardware achieves a Packet Error Rate (PER) of ∼0.1 at 550 kHz pulse center frequency, Synchronized-On Off Keying (S- OOK) modulation and 1 kbps data rate, for an average current consumption of 44mA
SN 2016coi (ASASSN-16fp): an energetic H-stripped core-collapse supernova from a massive stellar progenitor with large mass loss
We present comprehensive observations and analysis of the energetic
H-stripped SN 2016coi (a.k.a. ASASSN-16fp), spanning the -ray through
optical and radio wavelengths, acquired within the first hours to 420
days post explosion. Our campaign confirms the identification of He in the SN
ejecta, which we interpret to be caused by a larger mixing of Ni into the outer
ejecta layers. From the modeling of the broad bolometric light curve we derive
a large ejecta mass to kinetic energy ratio (, ). The small
[\ion{Ca}{ii}] \lam\lam7291,7324 to [\ion{O}{i}] \lam\lam6300,6364 ratio
(0.2) observed in our late-time optical spectra is suggestive of a large
progenitor core mass at the time of collapse. We find that SN 2016coi is a
luminous source of X-rays ( in the first
days post explosion) and radio emission ( at peak). These values are in line with those
of relativistic SNe (2009bb, 2012ap). However, for SN 2016coi we infer
substantial pre-explosion progenitor mass-loss with rate and a sub-relativistic shock
velocity , in stark contrast with relativistic SNe and similar
to normal SNe. Finally, we find no evidence for a SN-associated shock breakout
-ray pulse with energy . While we
cannot exclude the presence of a companion in a binary system, taken together,
our findings are consistent with a massive single star progenitor that
experienced large mass loss in the years leading up to core-collapse, but was
unable to achieve complete stripping of its outer layers before explosion.Comment: Submitted to ApJ. Main text: 21 pages; Appendix: 15 pages; 12 figure
Serum uric acid may modulate the inflammatory response after primary percutaneous coronary intervention in patients with ST-elevation myocardial infarction
Características de carcaça de bovinos Nelores, alimentados com rações à base de grão de milho inteiro, sem fibras longas, com diferentes níveis de substituição do grão de milho inteiro por casca de soja peletizada.
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