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ABSTRACTGanoderma boninense, the causal agent of basal stem rot (BSR) disease, has been recognized as a major economic threat to commercial plantings of oil palm (Elaeis guineensisJacq.) in Southeast Asia, which supplies 86% of the world’s palm oil. High genetic diversity and gene flow among regional populations of 417 G. boninenseisolates collected from Sabah, Sarawak, and Peninsular Malaysia (Malaysia) and Sumatra (Indonesia) were demonstrated using 16 microsatellite loci. Three genetic clusters and different admixed populations of G. boninenseacross regions were detected, and they appeared to follow the spread of the fungus from the oldest (Peninsular Malaysia and Sumatra) to younger generations of oil palm plantings (Sabah and Sarawak). Low spatial genetic differentiation of G. boninense(FST = 0.05) among the sampling regions revealed geographically nonrestricted gene dispersal, but isolation by distance was still evident. Analysis of molecular variance (AMOVA) confirmed the little to no genetic differentiation among the pathogen populations and the three genetic clusters defined by STRUCTURE and minimum spanning network. Despite G. boninensebeing highly outcrossing and spread by sexual spores, linkage disequilibrium was detected in 7 of the 14 populations. Linkage disequilibrium indicated that the reproduction of the fungus was not entirely by random mating and genetic drift could be an important structuring factor. Furthermore, evidence of population bottleneck was indicated in the oldest oil palm plantations as detected in genetic clusters 2 and 3, which consisted mainly of Peninsular Malaysia and Sumatra isolates. The population bottleneck or founding event could have arisen from either new planting or replanting after the removal of large number of palm hosts. The present study also demonstrated that migration and nonrandom mating of G. boninensecould be important for survival and adaptation to new palm hosts.

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ABSTRACTIn 1911 and 1917, the first commercial plantings of African oil palm (Elaeis guineensisJacq.) were made in Indonesia and Malaysia in Southeast Asia. In less than 15 years, basal stem rot (BSR) was reported in Malaysia. It took nearly another seven decades to identify the main causal agent of BSR as the fungus, Ganoderma boninense. Since then, research efforts have focused on understanding G. boninensedisease epidemiology, biology, and etiology, but limited progress was made to characterize pathogen genetic diversity, spatial structure, pathogenicity, and virulence. This study describes pathogen variability, gene flow, population differentiation, and genetic structure of G. boninensein Sarawak (Malaysia), Peninsular Malaysia, and Sumatra (Indonesia) inferred by 16 highly polymorphic cDNA-SSR (simple sequence repeat) markers. Marker-inferred genotypic diversity indicated a high level of pathogen variability among individuals within a population and among different populations. This genetic variability is clearly the result of outcrossing between basidiospores to produce recombinant genotypes. Although our results indicated high gene flow among the populations, there was no significant genetic differentiation among G. boninensepopulations on a regional scale. It suggested that G. boninensegenetic makeup is similar across a wide region. Furthermore, our results revealed the existence of three admixed genetic clusters of G. boninenseassociated with BSR-diseased oil palms sampled throughout Sarawak, Peninsular Malaysia, and Sumatra. We postulate that the population structure is likely a reflection of the high genetic variability of G. boninensepopulations. This, in turn, could be explained by highly successful outcrossing between basidiospores of G. boninensefrom Southeast Asia and introduced genetic sources from various regions of the world, as well as regional adaptation of various pathogen genotypes to different palm hosts. Pathogen variability and population structure could be employed to deduce the epidemiology of G. boninense, as well as the implications of plantation cultural practices on BSR disease control in different regions.

Dairy producers work extensively to ensure quality, but there is limited information on how poor experience with milk affects consumer choice. This study uses an online survey of 725 US consumers to assess how a poor experience with milk affects purchase behavior in different channels. We examine the relationship between product experience and purchase behavior and find that a poor experience is associated with a greater likelihood of switching stores and with lower net promoter scores, suggesting that having high quality milk may improve customer loyalty. This work highlights the important role that perishable food quality plays in retail settings.

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Background: It is important to identify the relevant parameters of physical performance to prevent early functional decline and to prolong independent living. The aim of this study is to describe the development of physical performance in a healthy community-dwelling older cohort aged 70+ years using comprehensive assessment over two years and to subsequently identify the most relevant predictive tests for physical decline to minimize assessment. Methods: Physical performance was measured by comprehensive geriatric assessment. Predictors for the individual decline of physical performance by Principal Component and k-means Cluster Analysis were developed, and sensitivity and specificity determined accordingly. Results: 251 subjects (Ø 75.4 years) participated in the study. Handgrip strength was low in 21.1%. The follow-up results of tests were divergent. Handgrip strength [− 16.95 (SD 11.55)] and the stair climb power test (power) [− 9.15 (SD 16.84)] yielded the highest percentage changes. Four most relevant tests (handgrip strength, stair climb power time, timed up & go and 4-m gait speed) were identified. A predictor based on baseline data was determined (sensitivity 82%, specificity 96%) to identify subjects characterized by a high degree of physical decline within two years. Discussion: Although the cohort of older adults is heterogeneous, most of the individuals in the study exhibited high levels of physical performance; only a few subjects suffered a relevant decline within the 2-year follow-up. Four most relevant tests were identified to predict relevant decline of physical function. Conclusion: In spite of ceiling effects of the geriatric assessment in high-performers, we assume that it is possible to predict an individual’s risk of physical decline within 2 years with four tests of a comprehensive geriatric assessment.

Background: The search for smart delivery systems for enhanced pre-clinical and clinical pharmaceutical delivery and cell targeting continues to be a major biomedical research endeavor owing to differences in the physicochemical characteristics and physiological effects of drug molecules, and this affects the delivery mechanisms to elicit maximum therapeutic effects. Targeted drug delivery is a smart evolution essential to address major challenges associated with conventional drug delivery systems. These challenges mostly result in poor pharmacokinetics due to the inability of the active pharmaceutical ingredients to specifically act on malignant cells thus, causing poor therapeutic index and toxicity to surrounding normal cells. Aptamers are oligonucleotides with engineered affinities to bind specifically to their cognate targets. Aptamers have gained significant interests as effective targeting elements for enhanced therapeutic delivery as they can be generated to specifically bind to wide range of targets including proteins, peptides, ions, cells and tissues. Notwithstanding, effective delivery of aptamers as therapeutic vehicles is challenged by cell membrane electrostatic repulsion, endonuclease degradation, low pH cleavage, and binding conformation stability. Objective: The application of molecularly engineered biodegradable and biocompatible polymeric particles with tunable features such as surface area and chemistry, particulate size distribution and toxicity creates opportunities to develop smart aptamer-mediated delivery systems for controlled drug release. Results: This article discusses opportunities for particulate aptamer-drug formulations to advance current drug delivery modalities by navigating active ingredients through cellular and biomolecular traffic to target sites for sustained and controlled release at effective therapeutic dosages while minimizing systemic cytotoxic effects. Conclusion: A proposal for a novel drug-polymer-aptamer-polymer (DPAP) design of aptamer-drug formulation with stage-wise delivery mechanism is presented to illustrate the potential efficacy of aptamer- polymer cargos for enhanced cell targeting and drug delivery.

We examined tolerance mechanisms in patients receiving HLA‐mismatched combined kidney–bone marrow transplantation (CKBMT) that led to transient chimerism under a previously published nonmyeloablative conditioning regimen (Immune Tolerance Network study 036). Polychromatic flow cytometry and high‐throughput sequencing of T cell receptor‐β hypervariable regions of DNAfrom peripheral blood regulatory T cells (Tregs) and CD4 non‐Tregs revealed marked early enrichment of Tregs (CD3+CD4+CD25highCD127lowFoxp3+) in blood that resulted from peripheral proliferation (Ki67+), possibly new thymic emigration (CD31+), and, in one tolerant subject, conversion from non‐Tregs. Among recovering conventional T cells, central memory CD4+and CD8+cells predominated. A large proportion of the T cell clones detected in posttransplantation biopsy specimens by T cell receptorsequencing were detected in the peripheral blood and were not donor‐reactive. Our results suggest that enrichment of Tregs by new thymic emigration and lymphopenia‐driven peripheral proliferation in the early posttransplantation period may contribute to tolerance after CKBMT. Further, most conventional T cell clones detected in immunologically quiescent posttransplantation biopsy specimens appear to be circulating cells in the microvasculature rather than infiltrating T cells. In patients receiving HLA‐mismatched combined kidney–bone marrow transplantation to induce transplantation tolerance, polychromatic flow cytometry and high‐throughput T cell receptor sequencing reveal an early enrichment of regulatory T cells, probably arising from new thymic emigration and lymphopenia‐driven peripheral proliferation, though the T cell receptors detected are likely from circulating T cells in the allograft microvasculature rather than infiltrating T cells.

Electrochemical anodisation is a well-received method in the complementary metal-oxide-semiconductor field as it is advantageous; best performed at room temperature which translates into being more affordable and a simple alternative to form nano-structured oxide films for different metals. The quintessential parameters involved allow numerous formations of metal oxide films according to desired morphology and thickness. Therefore, this paper aims to review the effects of anodising parameters such as applied voltage, concentration, temperature, time, current density and post-anodisation annealing among them.

Electrochemical anodisation is a well-received method in the complementary metal-oxide-semiconductor field as it is advantageous; best performed at room temperature which translates into being more affordable and a simple alternative to form nano-structured oxide films for different metals. The quintessential parameters involved allow numerous formations of metal oxide films according to desired morphology and thickness. Therefore, this paper aims to review the effects of anodising parameters such as applied voltage, concentration, temperature, time, current density and post-anodisation annealing among them.

Higher serum levels of uric acid are associated with preeclampsia and may signal an early change in preeclampsia. However there is less evidence suggesting there is a meaningful association between uric acid and the development of preeclampsia. A total of 877 women with preeclampsia at presentation and 580 normotensive pregnancies were retrospectively recruited from January 2009 to May 2014. In addition, 5556 pregnant women were also prospectively recruited from September 2012 to December 2013. Retrospective serum levels of uric acid were obtained from women with preeclampsia at the time of presentation (n=877), and serum levels of uric acid in the first, second and third trimester were prospectively collected in women who later developed preeclampsia (n=78), as well as those who did not (n=5478). The serum levels of uric acid were significantly increased in women with preeclampsia at presentation from retrospective samples and this increase correlated with the time of onset and the severity of preeclampsia. However, in prospective samples, serum levels of uric acid were not increased in the first and second trimesters in women who later developed preeclampsia compared with those who did not. The serum level of uric acid in the first and second trimesters in women who developed preeclampsia was not different. Our results demonstrate that the serum levels of uric acid were only increased after the presentation of clinical symptoms of preeclampsia. Therefore, it is likely that uric acid is not involved in the development of preeclampsia and cannot be an early prediction biomarker of this disease.

Blood chimerism has been reported sporadically among visceral transplant recipients, mostly in association with graft‐vs‐host disease (GVHD). We hypothesized that a higher degree of mixed chimerism would be observed in multivisceral (MVTx) than in isolated intestinal (iITx) and isolated liver transplant (iLTx) recipients, regardless of GVHD. We performed a longitudinal prospective study investigating multilineage blood chimerism with flow cytometry in 5 iITx and 4 MVTx recipients up to one year posttransplant. Although only one iITx patient experienced GVHD, T cell mixed chimerism was detected in 8 out of 9 iITx/MVTx recipients. Chimerism was significantly lower in the four subjects who displayed early moderate to severe rejection. Pre‐formed high‐titer donor‐specific antibodies, bound in vivoto the circulating donor cells, were associated with an accelerated decline in chimerism. Blood chimerism was also studied in 10 iLTx controls. Among nonsensitized patients, MVTx recipients exhibited greater T and B cell chimerism than either iITx or iLTx recipients. Myeloid lineage chimerism was present exclusively among iLTx and MVTx (6/13) recipients, suggesting that its presence required the hepatic allograft. Our study demonstrates, for the first time, frequent T cell chimerism without GVHD following visceral transplantation and a possible relationship with reduced rejection rate in MVTx recipients. This study shows the presence of peripheral blood macrochimerism, which can be long‐lasting in the absence of graft‐versus‐host disease in intestinal transplant recipients, and an association between T cell macrochimerism and lack of significant rejection, which occur more frequently in multivisceral than isolated intestinal transplant recipients.

This paper is to predict dominant factors influencing temporal sedimentation rates at Loagan Bunut Lake using best-fit model of sedimentation rate and distance from Bunut River. The lake is a flood plain lake located in Sarawak, Malaysia. Twenty two cylindrical traps were installed at the lake from November 2005 until April 2008. Each sample was collected after about four to five months of deployment. Dry sedimentation rates from the traps and the linear distances from Trap 1 located at the confluence of Bunut River were measured. The factors that influence the temporal sedimentation at the lake were both internal and external physical changes of the lake. The factors were net ws (net Stoke’s settling velocity) and water volume in the lake for suspended sediment distribution.

This work describes the design of a new plasmonic device made of gold nanoparticles separated from a gold film through a thermoresponsive polymer layer. This organic polymer responds to temperature variations by conformational changes (with a characteristic temperature called the lower critical solution temperature, LCST) and is therefore able to vary the distance between the gold nanoparticles and the gold film. The optical properties of these stimulable substrates were probed by Surface Enhanced Raman Scattering spectroscopy (SERS) using methylene blue (MB) as a molecular probe. We show that an increase of the external temperature reversibly induces a significant enhancement of the MB SERS signal. This was attributed to a stronger interaction between the gold nanoparticles and the gold substrate. The temperature-responsive plasmonic devices developed in this work thus provide a dynamic SERS platform, with thermally switchable electromagnetic coupling between the gold nanoparticles and the gold surface.

A method to study the solar flux distributions of the solar images reflected by mirrors with different dielectric thicknesses is proposed in this paper. An optical scanner, also known as a flux mapping system, capable of acquiring the flux distribution pattern of a light source in a two-dimensional flat surface, has been designed and constructed. The optical scanner can measure the profile of flux distribution at reasonably high resolution with fewer photo-sensors with a fast scanning speed of several seconds. The real time measurement results of solar images projected by mirrors with dielectric thicknesses, i.e., 3?mm, 4?mm, 5?mm and 6?mm, have been performed to analyze their surface qualities.