152 research outputs found

    Relationships between canopy Size and aboveground biomass of oil palms: an evaluation of allometric models

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    Oil palms (OP) in Sabah, Malaysia were studied to explore the relationship between canopy size and aboveground biomass (AGB). Four available allometric equations were used to calculate the dry AGB. Pearson’s correlation analysis was performed between crown diameter (CD) and crown area (CA) towards the variables of AGB, height and dbh. In this analysis, the transformation to natural log of variable resulted in better coefficient compared to the original one. The mean of various variables such as height (stem, total and height difference), biomass (crown, trunk and total), dbh (inner and outer) and number of petiole leaf were calculated based on 32 independent sample plots (N = 222 palms) across various age stages from 2 to 24 years. These variables were regressed against CD and age. AGB versus CD was a nonlinear with R2 ranging from 0.950 to 0.975. Random modelling and cross validation between AGB and CD was applied at the ratio of 70:30. Upon checking, the best estimation was achieved by using the allometric equation based on total height due to the lowest relative root mean square error (RMSE) (18.5%) and the least fluctuation between predicted and actual AGB. The other three models had relative RMSE that ranged between 23.9 and 68.8%. This study shows that AGB can be estimated using CD of OP consistently at all age

    An Opportunity to Increase Collaborative Science in Fetal, Infant, and Toddler Neuroimaging

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    The field of fetal, infant, and toddler (FIT) neuroimaging research—including magnetic resonance imaging (MRI), electroencephalography (EEG), magnetoencephalography, and functional near-infrared spectroscopy, among others—offers pioneering insights into early brain development and has grown in popularity over the past 2 decades. In broader neuroimaging research, multisite collaborative projects, data sharing, and open-source code have increasingly become the norm, fostering big data, consensus standards, and rapid knowledge transfer and development. Given the aforementioned benefits, along with recent initiatives from funding agencies to support multisite and multimodal FIT neuroimaging studies, the FIT field now has the opportunity to establish sustainable, collaborative, and open science practices. By combining data and resources, we can tackle the most pressing issues of the FIT field, including small effect sizes, replicability problems, generalizability issues, and the lack of field standards for data collection, processing, and analysis—together. Thus, the goals of this commentary are to highlight some of the potential barriers that have waylaid these efforts and to discuss the emerging solutions that have the potential to revolutionize how we work together to study the developing brain early in life

    Higher throughput quantification of neutralizing antibody to herpes simplex viruses

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    We report a rapid, higher throughput method for measuring neutralizing antibody to herpes simplex virus (HSV) in human sera. Clinical isolates and sera from the Herpevac Trial for Women were used in a colorimetric assay in which infection of tissue culture (lack of neutralization) was indicated by substrate metabolism by beta-galactosidase induced in the ELVIS cell line. The neutralization assay was optimized by addition of guinea pig complement, which particularly enhanced neutralizing antibody titers to HSV-2. Higher neutralizing antibody titers were also achieved using virus particles isolated from the supernatant of infected cells rather than lysate of infected cells as the source of virus. The effect of assay incubation time and incubation time with substrate were also optimized. We found that incubating with substrate until a standard optical density of 1.0 was reached permitted a better comparison among virus isolates, and achieved reliable measurement of neutralizing antibody activity. Interestingly, in contrast to results in the absence of complement, addition of complement allowed sera from HSV-2 gD-vaccinated subjects to neutralize HSV-1 and HSV-2 clinical and laboratory isolates with equal potency

    Dear reviewers: Responses to common reviewer critiques about infant neuroimaging studies

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    The field of adult neuroimaging relies on well-established principles in research design, imaging sequences, processing pipelines, as well as safety and data collection protocols. The field of infant magnetic resonance imaging, by comparison, is a young field with tremendous scientific potential but continuously evolving standards. The present article aims to initiate a constructive dialog between researchers who grapple with the challenges and inherent limitations of a nascent field and reviewers who evaluate their work. We address 20 questions that researchers commonly receive from research ethics boards, grant, and manuscript reviewers related to infant neuroimaging data collection, safety protocols, study planning, imaging sequences, decisions related to software and hardware, and data processing and sharing, while acknowledging both the accomplishments of the field and areas of much needed future advancements. This article reflects the cumulative knowledge of experts in the FIT\u27NG community and can act as a resource for both researchers and reviewers alike seeking a deeper understanding of the standards and tradeoffs involved in infant neuroimaging

    Assessing intraspecific wood density variations of Syzgium sp. in tropical forest of Southwest Sabah

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    Wood density (WD) is a critical determinant of estimating forest above-ground biomass (AGB) and carbon stock. Thus, heterogeneity in WD on individuals within species trees needs to be scrutinized, and acquisition of fixed WD value is essential to estimate carbon stock with confidence. This study investigated intraspecific variation in WD of Syzgium sp., also known as “Jambu” or “Kelat”. It is the most occurring species in study areas, and is regarded as an economically important species. Firstly, one half-diameter drilling from bark-to-pith measurement was taken per tree using Rinntech Resistograph R650-ED at breast height. Meanwhile, 5.15 mm-diameter core was sampled at 1.30 m above-ground, with DeWalt DCF899HP2 20V impact wrench 950 Nm and Haglöf increment borer. WD was estimated for each core sample using a dimensional method. Drilling resistance (DR) profiles were processed using DECOM 2.38m1 Scientific (c), and several independent variables were extracted from the resistogram. All resistogram-derived variables were positively correlated with field WD (R: 0.2 – 0.70). In addition, variability on WD in Syzgium sp. population is predominantly explained by the Resistograph amplitude, expressed as mean raw scale of adjusted DR (DRadj.RawSC) in a regression model. Given that intraspecific variation in WD is a crucial conjecture in forest AGB estimation, it is recommended to analyze with larger samples, and in-depth exploration on Resistograph-based variables is deemed to improve the accuracy of WD prediction models

    Corneal Replication Is an Interferon Response-Independent Bottleneck for Virulence of Herpes Simplex Virus 1 in the Absence of Virion Host Shutoff

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    Herpes simplex viruses lacking the virion host shutoff function (Δvhs) are avirulent and hypersensitive to type I and type II interferon (IFN). In this study, we demonstrate that even in the absence of IFN responses in AG129 (IFN-αÎČÎłR−/−) mice, Δvhs remains highly attenuated via corneal infection but is fully virulent via intracranial infection. The data demonstrate that the interferon-independent inherent replication defect of Δvhs has a significant impact upon peripheral replication and neuroinvasion

    Dear reviewers: responses to common reviewer critiques about infant neuroimaging studies

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    The field of adult neuroimaging relies on well-established principles in research design, imaging sequences, processing pipelines, as well as safety and data collection protocols. The field of infant magnetic resonance imaging, by comparison, is a young field with tremendous scientific potential but continuously evolving standards. The present article aims to initiate a constructive dialog between researchers who grapple with the challenges and inherent limitations of a nascent field and reviewers who evaluate their work. We address 20 questions that researchers commonly receive from research ethics boards, grant, and manuscript reviewers related to infant neuroimaging data collection, safety protocols, study planning, imaging sequences, decisions related to software and hardware, and data processing and sharing, while acknowledging both the accomplishments of the field and areas of much needed future advancements. This article reflects the cumulative knowledge of experts in the FIT'NG community and can act as a resource for both researchers and reviewers alike seeking a deeper understanding of the standards and tradeoffs involved in infant neuroimaging.R01 MH104324 - NIMH NIH HHS; UL1 TR001863 - NCATS NIH HHS; P50 MH115716 - NIMH NIH HHS; K01 MH108741 - NIMH NIH HHS; TL1 TR001864 - NCATS NIH HHS; R01 MH118285 - NIMH NIH HHS; U01 MH110274 - NIMH NIH HHS; P50 MH100029 - NIMH NIH HHS; ZIA MH002782 - Intramural NIH HHS; R01 EB027147 - NIBIB NIH HHS; R01 MH119251 - NIMH NIH HHS; UL1 TR003015 - NCATS NIH HHS; F31 HD102156 - NICHD NIH HHS; KL2 TR003016 - NCATS NIH HHS; T32 MH018268 - NIMH NIH HHSPublished versio
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