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1.
Heliyon ; 10(10): e30768, 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38774313

RESUMEN

Malaysia is the second largest producer and exporter of palm oil. Though several works have explored achieving emissions reduction in the palm oil sector, there existing gaps in analysing pathways for achieving net-zero emissions. Moreover, there are limited studies that evaluate the potential of palm oil biomass utilisation pathways based on emissions reduction capabilities, the cost of emissions reduction, and the technology readiness for implementation. Therefore, this study analysed decarbonisation pathways for the upstream and midstream segments of the palm oil sector in Malaysia, encompassing oil palm plantations and palm oil mills. Various sources of greenhouse gas emissions in oil palm plantations and palm oil mills were identified and estimates of emissions were determined as theoretical emissions. The current emissions were established based on the current best practice in the plantation and mill. Several biomass conversion technologies for the recovery of palm-based by-products and conversion into value-added products to decarbonise the palm oil sector and evaluated strategies to attain net-zero status are considered. In this work, the analysis considered both the existing technologies that are adopted by plantations and mills as well as the emerging technologies that have scope for implementation. With the proposed approach, the current emissions level for crude palm oil (CPO) production in Malaysia is estimated as 1121.49 kg CO2-eq/t CPO. In current industry practice, empty fruit bunch (EFB) is underutilised as mills are typically located at rural areas with lack of suitable transportation. Besides, the lack of accessibility to the grid also limits the potential of converting EFB into electricity as supply for national grid. This work examined various pathways for EFB utilisation under different scenarios evaluating their contribution potential towards net-zero target in an energy self-sustained CPO production. As shown in the results, converting EFB to briquettes and pellets are able to achieve the net-zero objective. Furthermore, EFB-biochar and EFB-syngas pathways also exhibit the potential to accomplish the net-zero target. Note that this work also assessed the technologies' readiness levels, identified challenges in implementation, and proposed several recommendations.

2.
Regul Toxicol Pharmacol ; 116: 104753, 2020 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-32745583

RESUMEN

Consumers are commonly exposed to numerous chemical ingredients found in various formulated products especially household and personal care products. Therefore, identification of hazardous ingredients contained in those products should be performed at the early stages of product design to reduce the high cost of redesigning the products at the final stage. Thus, a systematic safety and health risk assessment methodology is required for the product formulation design. In this work, a two-step index-based methodology is presented to estimate the severity of the hazards and the magnitude of risks. In Tier 1 assessment, potential hazards of the ingredients were identified by following the Product Ingredient Safety Index (PISI). The basic toxicology information of ingredients was required for this assessment. In Tier 2 assessment, the extent of risks of the ingredients via dermal and inhalation exposure routes were evaluated. At this stage, the concentration of ingredients and the amount of exposure were considered. The value of Margin of Exposure (MOE) was used as an indicator in the development of Product Ingredient Exposure Index (PIEI). To demonstrate the proposed methodology, a case study on the evaluation of potential hazards and the risks from ingredients used in personal care product formulations were performed.


Asunto(s)
Cosméticos/toxicidad , Exposición por Inhalación/efectos adversos , Medición de Riesgo/métodos , Piel/efectos de los fármacos , Animales , Seguridad de Productos para el Consumidor , Humanos
3.
Heliyon ; 5(10): e02594, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31720447

RESUMEN

Designers of energy systems often face challenges in balancing the trade-off between cost and reliability. In literature, several papers have presented mathematical models for optimizing the reliability and cost of energy systems. However, the previous models only addressed reliability implicitly, i.e., based on availability and maintenance planning. Others focused on allocation of reliability based on individual equipment requirements via non-linear models that require high computational effort. This work proposes a novel mixed-integer linear programming (MILP) model that combines the use of both input-output (I-O) modelling and linearized parallel system reliability expressions. The proposed MILP model can optimize the design and reliability of energy systems based on equipment function and operating capacity. The model allocates equipment with sufficient reliability to meet system functional requirements and determines the required capacity. A simple pedagogical example is presented in this work to illustrate the features of proposed MILP model. The MILP model is then applied to a polygeneration case study consisting of two scenarios. In the first scenario, the polygeneration system was optimized based on specified reliability requirements. The technologies chosen for Scenario 1 were the CHP module, reverse osmosis unit and vapour compression chiller. The total annualized cost (TAC) for Scenario 1 was 53.3 US$ million/year. In the second scenario, the minimum reliability level for heat production was increased. The corresponding results indicated that an additional auxiliary boiler must be operated to meet the new requirements. The resulting TAC for the Scenario 2 was 5.3% higher than in the first scenario.

4.
J Otolaryngol Head Neck Surg ; 45: 21, 2016 Mar 24.
Artículo en Inglés | MEDLINE | ID: mdl-27013057

RESUMEN

BACKGROUND: Guidelines and text-book descriptions of the Rinne test advise orienting the tuning fork tines in parallel with the longitudinal axis of the external auditory canal (EAC), presumably to maximise the amplitude of the air conducted sound signal at the ear. Whether the orientation of the tuning fork tines affects the amplitude of the sound signal at the ear in clinical practice has not been previously reported. The present study had two goals: determine if (1) there is clinician variability in tuning fork placement when presenting the air-conduction stimulus during the Rinne test; (2) the orientation of the tuning fork tines, parallel versus perpendicular to the EAC, affects the sound amplitude at the ear. METHODS: To assess the variability in performing the Rinne test, the Canadian Society of Otolaryngology - Head and Neck Surgery members were surveyed. The amplitudes of the sound delivered to the tympanic membrane with the activated tuning fork tines held in parallel, and perpendicular to, the longitudinal axis of the EAC were measured using a Knowles Electronics Mannequin for Acoustic Research (KEMAR) with the microphone of a sound level meter inserted in the pinna insert. RESULTS: 47.4 and 44.8% of 116 survey responders reported placing the fork parallel and perpendicular to the EAC respectively. The sound intensity (sound-pressure level) recorded at the tympanic membrane with the 512 Hz tuning fork tines in parallel with as opposed to perpendicular to the EAC was louder by 2.5 dB (95% CI: 1.35, 3.65 dB; p < 0.0001) for the fundamental frequency (512 Hz), and by 4.94 dB (95% CI: 3.10, 6.78 dB; p < 0.0001) and 3.70 dB (95% CI: 1.62, 5.78 dB; p = .001) for the two harmonic (non-fundamental) frequencies (1 and 3.15 kHz), respectively. The 256 Hz tuning fork in parallel with the EAC as opposed to perpendicular to was louder by 0.83 dB (95% CI: -0.26, 1.93 dB; p = 0.14) for the fundamental frequency (256 Hz), and by 4.28 dB (95% CI: 2.65, 5.90 dB; p < 0.001) and 1.93 dB (95% CI: 0.26, 3.61 dB; p = .02) for the two harmonic frequencies (500 and 4 kHz) respectively. CONCLUSIONS: Clinicians vary in their orientation of the tuning fork tines in relation to the EAC when performing the Rinne test. Placement of the tuning fork tines in parallel as opposed to perpendicular to the EAC results in a higher sound amplitude at the level of the tympanic membrane.


Asunto(s)
Conducción Ósea/fisiología , Conducto Auditivo Externo/fisiopatología , Pérdida Auditiva/diagnóstico , Pruebas Auditivas/instrumentación , Membrana Timpánica/fisiopatología , Diseño de Equipo , Pérdida Auditiva/fisiopatología , Humanos , Sonido
5.
Plant Sci ; 241: 238-45, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26706074

RESUMEN

Lamina joint inclination or leaf angle (the angle between the leaf blade and vertical culm) is a major trait of rice plant architecture. The plant hormone brassinosteroid (BR) is the main regulator of this trait, while other plant hormones, including ethylene, gibberellin, and auxin, also influence leaf angle. In this study, we found that methyl jasmonate (MeJA) also participates in regulating lamina joint inclination. MeJA decreased lamina joint inclination and inhibited the BR-induced increase in lamina joint inclination. Furthermore, addition of a BR synthesis inhibitor increased the extent of change in lamina joint inclination in response to treatment with a low concentration of MeJA (0.05 or 0.5mgL(-1)), but it did not alter the lamina joint inclination of plants treated with a high concentration of MeJA (5mgL(-1)). Further studies showed that MeJA treatment significantly repressed the expression of BR biosynthesis-related genes and decreased endogenous BRs levels. In addition, the lamina joint inclination in the OsBRI1 mutant d61-1 was less sensitive to MeJA compared with its wild type counterpart, and lithium chloride-induced inactivation of GSK3-like kinase, a negative regulator of BR signaling, partly rescued the MeJA-induced reduction in lamina joint inclination. Further studies showed that MeJA treatment reduced the mRNA levels of BR signaling and target genes. These results indicate that MeJA-inhibition of lamina joint inclination may depend on BR biosynthesis and the BR signaling pathway.


Asunto(s)
Acetatos/metabolismo , Brasinoesteroides/metabolismo , Ciclopentanos/metabolismo , Oryza/metabolismo , Oxilipinas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Transducción de Señal , Regulación de la Expresión Génica de las Plantas , Datos de Secuencia Molecular , Oryza/genética , Oryza/crecimiento & desarrollo , Hojas de la Planta/genética , Hojas de la Planta/crecimiento & desarrollo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Análisis de Secuencia de ADN
6.
PLoS One ; 10(2): e0118177, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25710173

RESUMEN

Gibberellins (GA) regulate various components of plant development. Iron and Mn plaque result from oxiding and hydroxiding Fe and Mn, respectively, on the roots of aquatic plant species such as rice (Oryza sativa L.). In this study, we found that exogenous gibberellic acid3 (GA3) spray decreased Fe plaque, but increased Mn plaque, with applications of Kimura B nutrient solution. Similar effects from GA3, leading to reduced Fe plaque and increased Mn plaque, were also found by scanning electron microscopy and energy dispersive X-ray spectrometric microanalysis. Reduced Fe plaque was observed after applying GA3 to the groups containing added Fe2+ (17 and 42 mg•L(-1)) and an increasing trend was detected in Mn plaques of the Mn2+ (34 and 84 mg•L(-1)) added treatments. In contrast, an inhibitor of GA3, uniconazole, reversed the effects of GA3. The uptake of Fe or Mn in rice plants was enhanced after GA3 application and Fe or Mn plaque production. Strong synergetic effects of GA3 application on Fe plaque production were detected. However, no synergetic effects on Mn plaque production were detected.


Asunto(s)
Giberelinas/farmacología , Hierro/metabolismo , Manganeso/metabolismo , Oryza/efectos de los fármacos , Oxidorreductasas de Alcohol/antagonistas & inhibidores , Oxidorreductasas de Alcohol/metabolismo , Ensayo de Inmunoadsorción Enzimática , Giberelinas/análisis , Giberelinas/metabolismo , Hierro/química , Manganeso/química , Microscopía Electrónica de Rastreo , Oryza/química , Oryza/crecimiento & desarrollo , Raíces de Plantas/química , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/metabolismo , Plantones/química , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Espectrometría por Rayos X , Triazoles/farmacología
7.
Plant Cell Rep ; 34(6): 1025-36, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25686579

RESUMEN

KEY MESSAGE: Our results show that methyl jasmonate induces plasma membrane H (+) -ATPase activity and subsequently influences the apoplastic pH of trichoblasts to maintain a cell wall pH environment appropriate for root hair development. Root hairs, which arise from root epidermal cells, are tubular structures that increase the efficiency of water absorption and nutrient uptake. Plant hormones are critical regulators of root hair development. In this study, we investigated the regulatory role of the plasma membrane (PM) H(+)-ATPase in methyl jasmonate (MeJA)-induced root hair formation. We found that MeJA had a pronounced effect on the promotion of root hair formation in lettuce seedlings, but that this effect was blocked by the PM H(+)-ATPase inhibitor vanadate. Furthermore, MeJA treatment increased PM H(+)-ATPase activity in parallel with H(+) efflux from the root tips of lettuce seedlings and rhizosphere acidification. Our results also showed that MeJA-induced root hair formation was accompanied by hydrogen peroxide accumulation. The apoplastic acidification acted in concert with reactive oxygen species to modulate root hair formation. Our results suggest that the effect of MeJA on root hair formation is mediated by modulation of PM H(+)-ATPase activity.


Asunto(s)
Acetatos/farmacología , Membrana Celular/metabolismo , Ciclopentanos/farmacología , Lactuca/crecimiento & desarrollo , Oxilipinas/farmacología , ATPasas de Translocación de Protón/metabolismo , Acetatos/metabolismo , Ciclopentanos/metabolismo , Peróxido de Hidrógeno/metabolismo , Concentración de Iones de Hidrógeno , Lactuca/efectos de los fármacos , Lactuca/metabolismo , Oxilipinas/metabolismo , Reguladores del Crecimiento de las Plantas/metabolismo , Proteínas de Plantas/metabolismo , Raíces de Plantas/crecimiento & desarrollo , ATPasas de Translocación de Protón/antagonistas & inhibidores , Especies Reactivas de Oxígeno/metabolismo , Rizosfera , Plantones/efectos de los fármacos , Plantones/crecimiento & desarrollo , Plantones/metabolismo , Vanadatos/farmacología
8.
Plant Cell Rep ; 34(3): 483-94, 2015 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-25540118

RESUMEN

KEY MESSAGE: We used auxin-signalling mutants, auxin transport mutants, and auxin-related marker lines to show that exogenously applied GA enhances auxin-induced root inhibition by affecting auxin signalling and transport. Variation in root elongation is valuable when studying the interactions of phytohormones. Auxins influence the biosynthesis and signalling of gibberellins (GAs), but the influence of GAs on auxins in root elongation is poorly understood. This study was conducted to investigate the effect of GA3 on Arabidopsis root elongation in the presence of auxin. Root elongation was inhibited in roots treated with both IAA and GA3, compared to IAA alone, and the effect was dose dependent. Further experiments showed that GA3 could modulate auxin signalling based on root elongation in auxin-signalling mutants and the expression of auxin-responsive reporters. The GA3-enhanced inhibition of root elongation observed in the wild type was not found in the auxin-signalling mutants tir1-1 and axr1-3. GA3 increased DR5::GUS expression in the root meristem and elongation zones, and IAA2::GUS in the columella. The DR5rev::GFP signal was enhanced in columella cells of the root caps and in the elongation zone in GA3-treated seedling roots. A reduction was observed in the stele of PAC-treated roots. We also examined the effect of GA3 on auxin transport. The enhanced responsiveness caused by GA3 was not observed in the auxin influx mutant aux1-7 or the efflux mutant eir1-1. Additional molecular data demonstrated that GA3 could promote auxin transport via AUX1 and PIN proteins. However, GA3-induced PIN gene expression did not fully explain GA-enhanced PIN protein accumulation. These results suggest that GA3 is involved in auxin-mediated primary root elongation by modulating auxin signalling and transport, and thus enhances root responsiveness to exogenous IAA.


Asunto(s)
Arabidopsis/metabolismo , Giberelinas/farmacología , Ácidos Indolacéticos/metabolismo , Raíces de Plantas/metabolismo , Arabidopsis/efectos de los fármacos , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Transporte Biológico/efectos de los fármacos , Regulación de la Expresión Génica de las Plantas/efectos de los fármacos , Giberelinas/metabolismo , Ácidos Indolacéticos/farmacología , Proteínas de Transporte de Membrana/genética , Proteínas de Transporte de Membrana/metabolismo , Raíces de Plantas/efectos de los fármacos , Raíces de Plantas/genética , Plantas Modificadas Genéticamente , Transducción de Señal/efectos de los fármacos
9.
PLoS One ; 8(12): e84580, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24386397

RESUMEN

In plants, salicylic acid (SA) is a signaling molecule that regulates disease resistance responses, such as systemic acquired resistance (SAR) and hypertensive response (HR). SA has been implicated as participating in various biotic and abiotic stresses. This study was conducted to investigate the role of SA in adventitious root formation (ARF) in mung bean (Phaseolus radiatus L) hypocotyl cuttings. We observed that hypocotyl treatment with SA could significantly promote the adventitious root formation, and its effects were dose and time dependent. Explants treated with SA displayed a 130% increase in adventitious root number compared with control seedlings. The role of SA in mung bean hypocotyl ARF as well as its interaction with hydrogen peroxide (H2O2) were also elucidated. Pretreatment of mung bean explants with N, N'-dimethylthiourea (DMTU), a scavenger for H2O2, resulted in a significant reduction of SA-induced ARF. Diphenyleneiodonium (DPI), a specific inhibitor of membrane-linked NADPH oxidase, also inhibited the effect of adventitious rooting triggered by SA treatment. The determination of the endogenous H2O2 level indicated that the seedlings treated with SA could induce H2O2 accumulation compared with the control treatment. Our results revealed a distinctive role of SA in the promotion of adventitious rooting via the process of H2O2 accumulation. This conclusion was further supported by antioxidant enzyme activity assays. Based on these results, we conclude that the accumulation of free H2O2 might be a downstream event in response to SA-triggered adventitious root formation in mung bean seedlings.


Asunto(s)
Antiinfecciosos/farmacología , Fabaceae/metabolismo , Hipocótilo/metabolismo , Raíces de Plantas/metabolismo , Ácido Salicílico/farmacología , Sistemas de Mensajero Secundario/efectos de los fármacos , Depuradores de Radicales Libres/farmacología , Peróxido de Hidrógeno/metabolismo , Tiourea/análogos & derivados , Tiourea/farmacología
10.
J Exp Bot ; 58(10): 2441-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17556768

RESUMEN

Cytoplasmic male sterile (CMS) rice Zhenshan 97A (ZS97A) has been widely used in hybrid rice production in China. However, ZS97A suffers from serious panicle enclosure, which blocks normal pollination and greatly reduces seed production of hybrid rice. Little is known about the cause of panicle closure in ZS97A. In this study, it was found that the occurrence of cytoplasmic male sterility caused a deficiency of indole-3-acetic acid (IAA) in ZS97A panicles, and less IAA was provided to the uppermost internode (UI). Further, it was found that the decreased panicle-derived IAA caused a gibberellin A(1) (GA(1)) deficiency in the UI by the down-regulation of OsGA3ox2 transcript level. Reduced GA(1) level in the UI led to decreases of both cell number and cell elongation, resulting in a shortened UI. The shortened UI was unable to push the panicle out of the flag leaf sheath that remained normal, which resulted in panicle enclosure in ZS97A. These findings suggest that decreased panicle-derived IAA reduces the GA(1) level in the UI, causing panicle enclosure in CMS rice ZS97A.


Asunto(s)
Giberelinas/metabolismo , Ácidos Indolacéticos/metabolismo , Oryza/fisiología , Giberelinas/biosíntesis , Hibridación Genética , Oryza/genética , Oryza/crecimiento & desarrollo , Peroxidasas/metabolismo , Polen/fisiología , Polinización/fisiología
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