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1.
Conserv Biol ; 36(3): e13873, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34865262

RESUMO

Tree diversity in Asia's tropical and subtropical forests is central to nature-based solutions. Species vulnerability to multiple threats, which affect provision of ecosystem services, is poorly understood. We conducted a region-wide, spatially explicit assessment of the vulnerability of 63 socioeconomically important tree species to overexploitation, fire, overgrazing, habitat conversion, and climate change. Trees were selected for assessment from national priority lists, and selections were validated by an expert network representing 20 countries. We used Maxent suitability modeling to predict species distribution ranges, freely accessible spatial data sets to map threat exposures, and functional traits to estimate threat sensitivities. Species-specific vulnerability maps were created as the product of exposure maps and sensitivity estimates. Based on vulnerability to current threats and climate change, we identified priority areas for conservation and restoration. Overall, 74% of the most important areas for conservation of these trees fell outside protected areas, and all species were severely threatened across an average of 47% of their native ranges. The most imminent threats were overexploitation and habitat conversion; populations were severely threatened by these factors in an average of 24% and 16% of their ranges, respectively. Our model predicted limited overall climate change impacts, although some study species were likely to lose over 15% of their habitat by 2050 due to climate change. We pinpointed specific natural areas in Borneo rain forests as hotspots for in situ conservation of forest genetic resources, more than 82% of which fell outside designated protected areas. We also identified degraded areas in Western Ghats, Indochina dry forests, and Sumatran rain forests as hotspots for restoration, where planting or assisted natural regeneration will help conserve these species, and croplands in southern India and Thailand as potentially important agroforestry options. Our results highlight the need for regionally coordinated action for effective conservation and restoration.


Especies de Árboles Valoradas y Amenazadas de Asia Tropical y Subtropical Resumen La diversidad de árboles en los bosques tropicales y subtropicales de Asia es un eje central para las soluciones basadas en la naturaleza. La vulnerabilidad de las especies ante las múltiples amenazas, las cuales afectan el suministro de servicios ambientales, es un tema poco comprendido. Realizamos una evaluación regional espacialmente explícita de la vulnerabilidad de 63 especies de árboles de importancia socioeconómica ante la sobreexplotación, incendios, sobrepastoreo, conversión del hábitat y cambio climático. Los árboles se seleccionaron para su evaluación a partir de listas nacionales de prioridades, y las selecciones fueron validadas por una red de expertos de 20 países. Usamos el modelado de idoneidad Maxent para predecir el rango de distribución de las especies, conjuntos de datos espaciales de libre acceso para mapear la exposición a las amenazas y rasgos funcionales para estimar la susceptibilidad a las amenazas. Con base en la vulnerabilidad a las amenazas actuales y al cambio climático, identificamos las áreas prioritarias para su conservación y restauración. En general, el 74% de las áreas más importantes para la conservación de estos árboles quedó fuera de las áreas protegidas y todas las especies estaban seriamente amenazadas en promedio en el 47% de su distribución nativa. Las amenazas más inminentes fueron la sobreexplotación y la conversión del hábitat; las poblaciones estuvieron seriamente amenazadas por estos factores en promedio en el 24% y 16% de su distribución, respectivamente. Nuestro modelo predijo un impacto general limitado del cambio climático, aunque algunas especies estudiadas tuvieron la probabilidad de perder más del 15% de su hábitat para el 2050 debido a este factor. Identificamos áreas naturales específicas en las selvas de Borneo como puntos calientes para la conservación in situ de los recursos genéticos forestales, más del 82% de los cuales estaban fuera de las áreas protegidas designadas. También identificamos áreas degradadas en los Ghats Occidentales, los bosques secos de Indochina y las selvas de Sumatra como puntos calientes para la restauración, en donde la siembra o la regeneración natural asistida ayudarán a conservar estas especies. Además, identificamos campos de cultivo al sur de India y Tailandia como potenciales opciones importantes de agrosilvicultura. Nuestros resultados resaltan la necesidad de acciones regionales coordinadas para la conservación y restauración efectivas.


Assuntos
Ecossistema , Árvores , Mudança Climática , Conservação dos Recursos Naturais , Florestas , Tailândia
2.
Sensors (Basel) ; 22(13)2022 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-35808180

RESUMO

Product warranty seals or stickers are criteria for after-sale warranty services. The unauthorized removal or modification of a seal will void the warranty. So far, there is no detection method to confirm the warranty, other than the visual inspection of the deformation of the seal. Hence, a system to detect, read, and record the 'warranty' seal deformation is presented in this paper. A flexible piezoelectric sensor was used to determine the mechanical impacts of the seal. Three major impacts are discussed and evaluated in this paper-partial removal, complete removal, and drop deformations of the seal. These impacts were compared with the ambient responses to distinguish the conditions. All three impact cases show distinct characteristics in terms of sensor values, pulses, and pulse widths. For partial removal and complete removal of the seal, both cases exhibited maximum sensor values but differed in pulse and pulse width. A partially removed seal experienced the maximum number of pulses while complete removal experienced the maximum pulse width. However, if the seal experienced a drop impact, it showed lower sensor values, with the lowest pulse and pulse width. Hence, an algorithm was applied to generalize the conditions and decisions of warranty violations.

3.
Ecotoxicol Environ Saf ; 211: 111905, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33453636

RESUMO

The constant increase of heavy metals into the aqueous environment has become a contemporary global issue of concern to government authorities and the public. The study assesses the concentration, distribution, and risk assessment of heavy metals in freshwater from the Linggi River, Negeri Sembilan, Malaysia. Species sensitivity distribution (SSD) was utilised to calculate the cumulative probability distribution of toxicity from heavy metals. The aquatic organism's toxicity data obtained from the ECOTOXicology knowledgebase (ECOTOX) was used to estimate the predictive non-effects concentration (PNEC). The decreasing sequence of hazardous concentration (HC5) was manganese > aluminium > copper > lead > arsenic > cadmium > nickel > zinc > selenium, respectively. The highest heavy metal concentration was iron with a mean value of 45.77 µg L-1, followed by manganese (14.41 µg L-1) and aluminium (11.72 µg L-1). The mean heavy metal pollution index (HPI) value in this study is 11.52, implying low-level heavy metal pollutions in Linggi River. The risk quotient (RQ) approaches were applied to assess the potential risk of heavy metals. The RQ shows a medium risk of aluminium (RQm = 0.1125) and zinc (RQm = 0.1262); a low risk of arsenic (RQm = 0.0122) and manganese (RQm = 0.0687); and a negligible risk of cadmium (RQm = 0.0085), copper (RQm = 0.0054), nickel (RQm = 0.0054), lead (RQm = 0.0016) and selenium (RQm = 0.0012). The output of this study produces comprehensive pollution risk, thus provides insights for the legislators regarding exposure management and mitigation.


Assuntos
Metais Pesados/toxicidade , Poluentes Químicos da Água/toxicidade , Arsênio/análise , Cádmio/análise , Cobre/análise , Ecotoxicologia , Monitoramento Ambiental , Água Doce , Ferro , Malásia , Manganês , Metais Pesados/análise , Níquel/análise , Medição de Risco , Rios , Poluentes Químicos da Água/análise , Zinco/análise
4.
Sensors (Basel) ; 21(10)2021 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-34065920

RESUMO

Various aspects of task execution load balancing of Internet of Things (IoTs) networks can be optimised using intelligent algorithms provided by software-defined networking (SDN). These load balancing aspects include makespan, energy consumption, and execution cost. While past studies have evaluated load balancing from one or two aspects, none has explored the possibility of simultaneously optimising all aspects, namely, reliability, energy, cost, and execution time. For the purposes of load balancing, implementing multi-objective optimisation (MOO) based on meta-heuristic searching algorithms requires assurances that the solution space will be thoroughly explored. Optimising load balancing provides not only decision makers with optimised solutions but a rich set of candidate solutions to choose from. Therefore, the purposes of this study were (1) to propose a joint mathematical formulation to solve load balancing challenges in cloud computing and (2) to propose two multi-objective particle swarm optimisation (MP) models; distance angle multi-objective particle swarm optimization (DAMP) and angle multi-objective particle swarm optimization (AMP). Unlike existing models that only use crowding distance as a criterion for solution selection, our MP models probabilistically combine both crowding distance and crowding angle. More specifically, we only selected solutions that had more than a 0.5 probability of higher crowding distance and higher angular distribution. In addition, binary variants of the approaches were generated based on transfer function, and they were denoted by binary DAMP (BDAMP) and binary AMP (BAMP). After using MOO mathematical functions to compare our models, BDAMP and BAMP, with state of the standard models, BMP, BDMP and BPSO, they were tested using the proposed load balancing model. Both tests proved that our DAMP and AMP models were far superior to the state of the art standard models, MP, crowding distance multi-objective particle swarm optimisation (DMP), and PSO. Therefore, this study enables the incorporation of meta-heuristic in the management layer of cloud networks.

5.
J Anim Ecol ; 89(6): 1350-1364, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32173904

RESUMO

Identifying the drivers of population fluctuations in spatially distinct populations remains a significant challenge for ecologists. Whereas regional climatic factors may generate population synchrony (i.e. the Moran effect), local factors including the level of density dependence may reduce the level of synchrony. Although divergences in the scaling of population synchrony and spatial environmental variation have been observed, the regulatory factors that underlie such mismatches are poorly understood. Few previous studies have investigated how density-dependent processes and population-specific responses to weather variation influence spatial synchrony at both local and regional scales. We addressed this issue in a pond-breeding amphibian, the great crested newt Triturus cristatus. We used capture-recapture data collected through long-term surveys in five T. cristatus populations in Western Europe. In all populations-and subpopulations within metapopulations-population size, annual survival and recruitment fluctuated over time. Likewise, there was considerable variation in these demographic rates between populations and within metapopulations. These fluctuations and variations appear to be context-dependent and more related to site-specific characteristics than local or regional climatic drivers. We found a low level of demographic synchrony at both local and regional levels. Weather has weak and spatially variable effects on survival, recruitment and population growth rate. In contrast, density dependence was a common phenomenon (at least for population growth) in almost all populations and subpopulations. Our findings support the idea that the Moran effect is low in species where the population dynamics more closely depends on local factors (e.g. population density and habitat characteristics) than on large-scale environmental fluctuation (e.g. regional climatic variation). Such responses may have far-reaching consequences for the long-term viability of spatially structured populations and their ability to respond to large-scale climatic anomalies.


Assuntos
Anfíbios , Crescimento Demográfico , Animais , Europa (Continente) , Densidade Demográfica , Dinâmica Populacional
6.
Inflammopharmacology ; 28(5): 1195-1218, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32617790

RESUMO

The therapeutic efficacy of the contemporary anti-inflammatory drugs are well established; however, prolonged use of such can often lead to serious and life-threatening side effects. Natural product-based anti-inflammatory compounds with superior efficacy and minimum toxicity can serve as possible therapeutic alternatives in this scenario. Genus Uvaria is a part of Annonaceae family, while the majority of its species are widely distributed in tropical rain forest regions of South East Asia. Uvaria species have been used extensively used as traditional medicine for treating all sorts of inflammatory diseases including catarrhal inflammation, rheumatism, acute allergic reactions, hemorrhoids, inflammatory liver disease and inflamed joints. Phytochemical analysis of Uvaria species has revealed flavones, flavonoids, tannins, saponins, polyoxygenated cyclohexene and phenolic compounds as major phyto-constituents. This review is an attempt to highlight the anti-inflammatory activity of Uvaria species by conducting a critical appraisal of the published literature. The ethnopharmacological relevance of Uvaria species in the light of toxicological studies is also discussed herein. An extensive and relevant literature on anti-inflammatory activity of Uvaria species was collected from available books, journals and electronic databases including PubMed, ScienceDirect, Scopus, Proquest and Ovid. Extracts and isolates of Uvaria species exhibited significant anti-inflammatory activity through various mechanisms of action. 6,7-di-O-Methyl-baicalein, flexuvarol B, chrysin, (-)-zeylenol, 6-hydroxy-5,7-dimethoxy-flavone, and pinocembrin were the most potent anti-inflammatory compounds with comparable IC50 with positive controls. Therefore, it is suggested that further research should be carried out to determine the pharmacokinetics, pharmacodynamics and toxicity of these therapeutically significant compounds, to convert the pre-clinical results into clinical data for drug development and design.


Assuntos
Inflamação/tratamento farmacológico , Extratos Vegetais/farmacologia , Uvaria/química , Animais , Anti-Inflamatórios/farmacologia , Humanos , Medicina Tradicional/métodos , Compostos Fitoquímicos/farmacologia , Fitoterapia/métodos
7.
Cureus ; 16(6): e61734, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38975407

RESUMO

Warthin's tumor, also known as adenolymphoma or papillary cystadenoma lymphomatosum, is a benign tumor almost exclusively found in the parotid gland and is the second most common type of benign parotid tumor. Its manifestation as an extraparotid lesion is rare, with a low incidence in the submandibular gland. In this context, we present a case of Warthin's tumor of the submandibular gland in a 66-year-old man who presented with a painless lateral cystic cervical mass. This case highlights the clinical and radiological evidence of an uncommon extraparotid tumor location, with the diagnosis becoming evident only after the enucleation of the mass. Despite the rarity of extraparotid Warthin's tumor and its potential variation in location, the authors recommend considering Warthin's tumor of the submandibular gland in the differential when assessing lateral cervical masses.

8.
PLoS One ; 19(5): e0303406, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38748721

RESUMO

INTRODUCTION: Malaria is a vector-borne disease that initially manifests as fever, headache, and chills. The illness could progress to more severe conditions, including lethargy, impaired consciousness, convulsions, shortness of breath, blood in urine, jaundice, and haemorrhage if left untreated. The risk of contracting malaria is considerably heightened in specific occupational settings, particularly among forest rangers, following frequent exposure to natural habitats. Consequently, advancing the understanding of malaria and emphasising how specific occupational environments (including those of forest rangers) contribute to disease risk and management is imperative. OBJECTIVE: The present study aims to determine the factors associated with malaria infection among forest rangers by systematically reviewing electronic articles from three databases (EBSCOhost, ScienceDirect, and ResearchGate). METHODS: The current review was prepared based on the updated preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. First, three independent reviewers screened the titles and abstracts of the data collected. The information was then stored in Endnote20 based on the inclusion and exclusion criteria. The articles were critically appraised with the mixed methods appraisal tool (MMAT) to assess their quality. RESULT: A total of 103, 31, and 51 articles from EBSCOhost, ScienceDirect, and ResearchGate, respectively, were selected, resulting in 185 unique hits. Nevertheless, only 63 full-text publications were assessed following a rigorous selection screening, from which only five were included in the final review. The studies revealed that several factors contribute to malaria infection among forest rangers. The parameters were classified into sociodemographic, individual, and living condition-related. CONCLUSION: A better understanding of malaria progresses and identifying its potential risk factors is essential to impact worker well-being. The findings might be utilised to improve malaria infection prevention programme implementations, hence maximising their success. Pre-employment and regular health screenings could also aid in evaluating and identifying potential risks for malaria infection among forest rangers.


Assuntos
Florestas , Malária , Humanos , Malária/epidemiologia , Fatores de Risco , Animais
9.
Environ Sci Pollut Res Int ; 31(35): 48608-48619, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39037622

RESUMO

Stochastic modeling approaches have attracted many researchers to the field. However, fire hotspot detection suffers from not using a Markov chain quasi-Monte Carlo (MCQMC) as a forecasting methodology. This paper proposes improvements to the computational time by combining the strengths of the Markov chain Monte Carlo (MCMC) and quasi-Monte Carlo (QMC) methods. The proposed method can lead to more precise and stable results, particularly in problems with high-dimensional integration or complex probability distributions. The proposed method is applied to a case study of fire hotspot detection in Sarawak, Malaysia. The outcome of this study reveals that the MCQMC method is more computationally efficient, taking only 0.0746 seconds compared to MCMC's 0.0914 seconds and QMC's 0.0994 seconds. It is shown that the best option derived by the proposed method is effective in predicting fire hotspots and providing quick solutions to protect the environment and communities from forest fires.


Assuntos
Incêndios , Cadeias de Markov , Método de Monte Carlo , Malásia , Previsões
10.
J Genet Eng Biotechnol ; 21(1): 45, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37093363

RESUMO

BACKGROUND: Pectinase is helpful in food and beverage industries, particularly in the preparation of fruit juice, the extraction of vegetable oil, and the fermentation of coffee. The current work aimed to screen Aspergillus niger LFP-1, a recently identified fungal strain, for its ability to produce pectinase and to ascertain the contribution of various physicochemical factors to pectinase production. RESULTS: The primary and secondary pectinase activity screenings by Aspergillus niger LFP-1 were performed using pectin screening agar and shake flask system, respectively. The finding revealed that the locally isolated strain is able to secrete favourable pectinase production. Before improvement, the pectinase production was 0.88 ± 0.09 U/mL. However, the improved conditions such as 6 days of the cultivation period, agitation speed of 150 rpm, inoculum size of 1 × 106 spores/mL, 2.5% (w/v) citrus pectin, and 0.4% (w/v) ammonium nitrate could significantly increase pectinase production up to 7.41 ± 0.24 U/mL, representing an 88% increase. In this study, supplementing 2.5% (w/v) citrus pectin to the culture medium as a carbon source increased enzyme production by up to 3.07 ± 0.17 U/mL. Meanwhile, 0.4% (w/v) ammonium nitrate was used as a nitrogen source yielding the highest enzyme activity with a value of 6.86 ± 0.07 U/mL. CONCLUSION: Thus, the locally isolated fungal strain, A. niger LFP-1 has outstanding pectinase-producing capability and can be utilized for the commercial production of pectinase. The improved cultural conditions significantly increase pectinase production and shorten the incubation period from 8 days (before improvement) to 6 days (after improvement).

11.
Sci Rep ; 12(1): 18698, 2022 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-36333525

RESUMO

The presence of metal with microwave irradiation has always invited controversial arguments as the metal will catch on fire easily. But interestingly, researchers found that arc discharge phenomena provide a promising way for molecule cracking to synthesize nanomaterials. This study developed a single-step yet affordable synthesis approach that combines microwave heating and arcing in transforming crude palm oil into magnetic nanocarbon (MNC), which can be considered a new alternative for the palm oil sectors. It involves synthesizing the medium at a partial inert condition with constant coiled stainless steel metal wire (dielectric media) and ferrocene (catalyst). This approach successfully demonstrates heating at a temperature ranging from 190.9 to 472.0 °C with different synthesis times (10-20 min). The produced MNC shows formations of spheres with average sizes of 20.38-31.04 nm, mesoporous structure (SBET: 14.83-151.95 m2/g), and high content of fixed carbon (52.79-71.24wt%), and the ratio of the D and G bands (ID/IG) is 0.98-0.99. The formation of new peaks in the FTIR spectra (522.29-588.48 cm-1) supports the appearance of the FeO compounds from the ferrocene. The magnetometer shows high magnetization saturation (22.32-26.84 emu/g) in ferromagnetic materials. The application of the MNC in wastewater treatment has been demonstrated by evaluating their adsorbent capability with Methylene Blue (MB) adsorption test at a different concentrations varying between 5 and 20 ppm. The MNC produced at synthesis time (20 min) shows the highest adsorption efficiency (10.36 mg/g) compared to others, with 87.79% removal of MB dye. As a result, the value for Langmuir is not promising compared to Freundlich, with R2 being around 0.80, 0.98, and 0.99 for MNC synthesized at 10 min (MNC10), 15 min (MNC15), and 20 min (MNC20), respectively. Hence, the adsorption system is in a heterogeneous condition. The microwave-assisted arcing thereby presents a promising approach to transforming CPO into MNC that could remove the hazardous dye.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Óleo de Palmeira/química , Metalocenos , Micro-Ondas , Adsorção , Poluentes Químicos da Água/química
12.
Biomass Convers Biorefin ; : 1-32, 2022 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-35194538

RESUMO

Grown only in humid tropical conditions, the palm tree provides high-quality oil essential for cooking and personal care or biofuel in the energy sector. After the refining process, this demand could cause numerous oil palm biomass waste management problems. However, the emergence of carbon nanomaterials or CNMs could be a great way to put this waste to a good cause. The composition of the palm waste can be used as a green precursor or starting materials for synthesizing CNMs. Hence, this review paper summarizes the recent progress for the CNMs production for the past 10 years. This review paper extensively discusses the method for processing CNMs, chemical vapor deposition, pyrolysis, and microwave by the current synthesis method. The parameters and conditions of the synthesis are also analyzed. The application of the CNMs from palm oil and future recommendations are also highlighted. Generally, this paper could be a handy guide in assisting the researchers in exploring economic yet simple procedures in synthesizing carbon-based nanostructured materials derived from palm oil that can fulfill the required applications.

13.
Iran J Microbiol ; 14(3): 383-394, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37124849

RESUMO

Background and Objectives: Endophytic fungi are believed to possess compounds as antibacterial agents. This study was designed to determine in vivo antibacterial activity of the crude extracts from Lasiodiplodia pseudotheobromae IBRL OS-64 against pathogenic bacteria. Materials and Methods: The qualitative and quantitative screenings were performed using agar plug and disk diffusion antimicrobial tests, respectively. Besides that, the MIC and MBC value of the extracts were determined using broth microdilution assay and morphological changes of the bacterial cells exposed to the extract were observed under Scanning Electron Microscope (SEM). Results: Agar plug diffusion assay revealed that V. parahaemolyticus ATCC 17802 and Exiguobacterium profundum IBRL MA6 were the most sensitive to the extract with the size of inhibition zones of 11 to ≤ 20 mm. The MIC and MBC values of the extract varied depending on the test bacteria. Observation through SEM revealed that the bacterial cells exposed to the extract experienced severe damage such as irregular shape with crumpled and shrunken cells which led to cell death. Conclusion: The data suggest that the crude extracts of L. pseudotheobromae IBRL OS-64 exert antibacterial activity against test bacteria and principally affect the cell wall in growing pathogenic bacterial cells.

14.
Sci Rep ; 12(1): 9546, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35680966

RESUMO

International timber trade communities are increasingly demanding that timber in the wood supply chain be sourced from sustainably harvested forests and certified plantations. This is to combat illegal logging activities to prevent further depletion of our precious forests worldwide. Hence, timber tracking tools are important to support law enforcement officials in ensuring only sustainably harvested timbers are traded in the market. In this study, we developed chloroplast DNA (cpDNA) and simple sequence repeat (SSR) databases as tracking tools for an important tropical timber tree species, Shorea leprosula from Peninsular Malaysia. A total of 1410 individual trees were sampled from 44 natural populations throughout Peninsular Malaysia. Four cpDNA regions were used to generate a cpDNA haplotype database, resulting in a haplotype map comprising 22 unique haplotypes derived from 28 informative intraspecific variable sites. This cpDNA database can be used to trace the origin of an unknown log at the regional level. Ten SSR loci were used to develop the SSR allele frequency database. Bayesian cluster analysis divided the 44 populations into two genetic clusters corresponding to Region A and Region B. Based on conservativeness evaluation of the SSR databases for individual identification, the coancestry coefficients (θ) were adjusted to 0.1900 and 0.1500 for Region A and B, respectively. These databases are useful tools to complement existing timber tracking systems in ensuring only legally sourced timbers are allowed to enter the wood supply chain.


Assuntos
Dipterocarpaceae , Teorema de Bayes , DNA de Cloroplastos/genética , Bases de Dados de Ácidos Nucleicos , Dipterocarpaceae/genética , Repetições de Microssatélites/genética
15.
Forensic Sci Int Genet ; 57: 102658, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34998185

RESUMO

Aquilaria malaccensis (Thymelaeaceae) is the main source of high-grade agarwood in Southeast Asia. Aggressive collections and trade activities over the past decades have put great pressure on the natural stands and raised concerns over the long-term survival potential of A. malaccensis. Tracking and authentication of agarwood require method with a high degree of accuracy. Therefore, this study aimed to develop DNA databases of A. malaccensis as the tracking tools at species, population and individual levels for forensic identification and chain of custody certification. Using two cpDNA (rbcL and matK) and an rDNA (ITS2) markers, species identification database of Aquilaria was developed to distinguish A. malaccensis from A. hirta, A. microcarpa, A. beccariana, A. crassna, A. sinensis and A. rostrata. In addition, based on 35 populations of A. malaccensis throughout Peninsular Malaysia, cpDNA haplotype and STR allele frequency databases were developed for population and individual identification. A haplotype distribution map based on 29 haplotypes derived from seven cpDNA showed that the A. malaccensis in Peninsular Malaysia can be associated to Kedah-Perak and Kelantan-Johor regions. Similarly, genetic relatedness and Bayesian clustering analyses based on 10 STR markers also divided the 35 populations into two main genetic clusters, corresponding to Kedah-Perak and Kelantan-Johor regions. The STR allele frequency databases were established and characterized according to these two regions. To determine the performance of the STR allele frequency databases for population identification, independent self-assignment tests showed that the percentage of individuals correctly assigned into the origin population was 93.88% in Kedah-Perak and 90.29% in Kelantan-Johor. For the STR allele frequency databases to be used for individual identification, conservativeness tests showed that the θ should be adjusted to 0.250 and 0.200 in the Kedah-Perak and Kelantan-Johor databases, respectively. To ensure consistency in allele calling for the dinucleotide repeat loci across different electrophoretic platforms or laboratories, allelic ladders have been developed for the 10 STR loci. Two case studies are presented of how these databases were used to track A. malaccensis to the origin population and stump. These databases are ready to be used to provide admissible forensic evidence for legal proceedings against the illegal harvesters of agarwood and for agarwood certification to meet the consumer country regulations.


Assuntos
Thymelaeaceae , Teorema de Bayes , Certificação , DNA de Cloroplastos/genética , Bases de Dados de Ácidos Nucleicos , Humanos , Thymelaeaceae/genética
16.
ACS Omega ; 7(47): 42809-42818, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36467908

RESUMO

A Schiff base bearing two methyl substituents, namely, 6,6'-((1E,1'E)-((2,2-dimethylpropane-1,3-diyl) bis(azanylylidene)) bis(methanylylidene)) bis(2-methylphenol) [H2AD1Me] was synthesized and characterized through physicochemical and spectroscopic analyses. Then, the Schiff base was complexed with Pd(II) and Ni(II) to form [Pd(AD1Me)] and [Ni(AD1Me)], respectively. Both metal complexes were successfully obtained and characterized through several analyses, viz., melting point, elemental analysis, molar conductivity, magnetic susceptibility, FTIR, 1H NMR, UV-vis, and single crystal X-ray diffraction. A quantitative analysis of the intermolecular interactions in the crystal structures has been performed using Hirshfeld surface analysis. Both metal complexes were crystallized in a monoclinic crystal system with the space group of P21/c. Additionally, the deprotonated phenolic oxygen atom (O1/O2) and azomethine nitrogen atom (N1/N2) of the ligand chelate the Pd(II) and Ni(II) ions, forming a slightly distorted square-planar complex containing three six-membered rings encircling the metal core with dsp2 hybridization. The shift of ν(C=N) to a higher frequency in FTIR by 26-28 cm-1 indicated that the complexation to Pd(II) and Ni(II) through the azomethine N was established. It was further supported through the shifting of the azomethine proton signal to higher or lower chemical shifts with Δδ = 0.43-1.15 ppm in 1H NMR. In addition, the shifting of the n-π*(C=N) band in UV-vis spectra with Δλ = 24-40 nm indicated the involvement of azomethine nitrogen in the complexation. All the compounds showed no significant antibacterial activity against three bacterial strains, namely, Staphylococcus aureus subsp. aureus Rosenbach (ATCC 6538), Streptococcus mutans Clarke (ATCC 700,610), and Proteus vulgaris (ATCC 6380), as the percent growth inhibition calculated was less than 90%.

17.
Biomed Res Int ; 2021: 6679787, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34159198

RESUMO

The PadiU Putra rice line is a blast-resistant and high-yield rice line with high potential. The application of topdressing and the foliar applied method of silicon (Si) treatments could strengthen the culm to resist breakage and ultimately increase yield production. Treatments which consisted of a control, a Si topdressing, and a Si foliar applied were arranged in a randomised complete block design. At 55 days after transplanting (DAT), the foliar applied Si treatments had 59% higher dry matter partitioning to the roots. Meanwhile, at 75 DAT, both Si foliar applied and topdressing method showed increased assimilate partitioning into the culm sheath by 29% and 49%, respectively. Dark green and light yellowish colours were obtained in both Si treatments using UAV, indicating similar results to physiological responses. Remarkably, Si foliar applied treatments enhanced the diameter and width of the outer and inner layers of the diameter of vascular bundles at 75 DAT by 58, 181, and 80%, respectively. The yield production of rice increased by 53% in the Si foliar applied, compared to the control, and produced a 1.63 benefit-cost ratio.


Assuntos
Agricultura/métodos , Produtos Agrícolas , Oryza/efeitos dos fármacos , Silício/química , Biomassa , Clorofila , Malásia , Microscopia Eletrônica de Varredura , Fotossíntese , Folhas de Planta , Raízes de Plantas/química , Dióxido de Silício , Solo , Poluentes do Solo/análise
18.
Biomed Res Int ; 2020: 2706937, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32090071

RESUMO

Chilli (Capsicum annum L.) plant is a high economic value vegetable in Malaysia, cultivated in soilless culture containers. In soilless culture, the adoption of small container sizes to optimize the volume of the growing substrate could potentially reduce the production cost, but will lead to a reduction of plant growth and yield. By understanding the physiological mechanism of the growth reduction, several potential measures could be adopted to improve yield under restricted root conditions. The mechanism of growth reduction of plants subjected to root restriction remains unclear. This study was conducted to determine the physiological mechanism of growth reduction of root-restricted chilli plants grown in polyvinyl-chloride (PVC) column of two different volumes, 2392 cm3(root-restricted) and 9570 cm3(control) in soilless culture. Root restriction affected plant growth, physiological process, and yield of chilli plants. Root restriction reduced the photosynthesis rate and photochemical activity of PSII, and increased relative chlorophyll content. Limited root growth in root restriction caused an accumulation of high levels of sucrose in the stem and suggested a transition of the stem as a major sink organ for photoassimilate. Growth reduction in root restriction was not related to limited carbohydrate production, but due to the low sink demand from the roots. Reduction of the total yield per plant about, 23% in root restriction was concomitant, with a slightly increased harvest index which reflected an increased photoassimilate partitioning to the fruit production and suggested more efficient fruits production in the given small plant size of root restriction.


Assuntos
Capsicum/crescimento & desenvolvimento , Fotossíntese , Raízes de Plantas/fisiologia , Solo , Biomassa , Capsicum/anatomia & histologia , Clorofila/metabolismo , Condutividade Elétrica , Fluorescência , Frutas/anatomia & histologia , Gases/metabolismo , Folhas de Planta/anatomia & histologia , Caules de Planta/anatomia & histologia , Sacarose/metabolismo
19.
Forensic Sci Int Genet ; 44: 102188, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31648150

RESUMO

To inform product users about the origin of timber, the implementation of a traceability system is necessary for the forestry industry. In this study, we developed a comprehensive genetic database for the important tropical timber species Merbau, Intsia palembanica, to trace its geographic origin within peninsular Malaysia. A total of 1373 individual trees representing 39 geographically distinct populations of I. palembanica were sampled throughout peninsular Malaysia. We analyzed the samples using a combination of four chloroplast DNA (cpDNA) markers and 14 short tandem repeat (STR) markers to establish both cpDNA haplotype and STR allele frequency databases. A haplotype map was generated through cpDNA sequencing for population identification, resulting in six unique haplotypes based on 10 informative intraspecifically variable sites. Subsequently, an STR allele frequency database was developed from 14 STRs allowing individual identification. Bayesian cluster analysis divided the individuals into two genetic clusters corresponding to the northern and southern regions of peninsular Malaysia. Tests of conservativeness showed that the databases were conservative after the adjustment of the θ values to 0.2000 and 0.2900 for the northern (f = 0.0163) and southern (f = 0.0285) regions, respectively. Using self-assignment tests, we observed that individuals were correctly assigned to populations at rates of 40.54-94.12% and to the identified regions at rates of 79.80-80.62%. Both the cpDNA and STR markers appear to be useful for tracking Merbau timber originating from peninsular Malaysia. The use of these forensic tools in addition to the existing paper-based timber tracking system will help to verify the legality of the origin of I. palembanica and to combat illegal logging issues associated with the species.


Assuntos
Conservação dos Recursos Naturais , Bases de Dados Genéticas , Fabaceae/genética , Geografia , Crime , Impressões Digitais de DNA , DNA de Cloroplastos/genética , Frequência do Gene , Marcadores Genéticos , Haplótipos , Humanos , Malásia , Repetições de Microssatélites , Reação em Cadeia da Polimerase
20.
Sci Rep ; 10(1): 19112, 2020 11 05.
Artigo em Inglês | MEDLINE | ID: mdl-33154411

RESUMO

Worldwide, many mangrove species are experiencing significant population declines, including Rhizophora apiculata, which is one of the most widespread and economically important species in tropical Asia. In Malaysia, there has been an alarming decline in R. apiculata populations driven primarily by anthropogenic activities. However, the lack of genetic and demographic information on this species has hampered local efforts to conserve it. To address these gaps, we generated novel genetic information for R. apiculata, based on 1,120 samples collected from 39 natural populations in Peninsular Malaysia. We investigated its genetic diversity and genetic structure with 19 transcriptome and three nuclear microsatellite markers. Our analyses revealed a low genetic diversity (mean He: 0.352) with significant genetic differentiation (FST: 0.315) among populations of R. apiculata. Approximately two-third of the populations showed significant excess of homozygotes, indicating persistent inbreeding which might be due to the decrease in population size or fragmentation. From the cluster analyses, the populations investigated were divided into two distinct clusters, comprising the west and east coasts of Peninsular Malaysia. The western cluster was further divided into two sub-clusters with one of the sub-clusters showing strong admixture pattern that harbours high levels of genetic diversity, thus deserving high priority for conservation.


Assuntos
Evolução Biológica , Ecossistema , Espécies em Perigo de Extinção , Variação Genética , Rhizophoraceae/genética , Deriva Genética , Malásia , Repetições de Microssatélites
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