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Fulltext An improved model based on the support vector machine and cuckoo algorithm for simulating reference evapotranspiration

Ehteram M, Singh VP, Ferdowsi A, Mousavi SF, Farzin S, Karami H, et al.

PLoS One, 2019;14(5):e0217499.
PMID: 31150443 DOI: 10.1371/journal.pone.0217499

Reference evapotranspiration (ET0) plays a fundamental role in irrigated agriculture. The objective of this study is to simulate monthly ET0 at a meteorological station in India using a new method, an improved support vector machine (SVM) based on the cuckoo algorithm (CA), which is known as SVM-CA. Maximum temperature, minimum temperature, relative humidity, wind speed and sunshine hours were selected as inputs for the models used in the simulation. The results of the simulation using SVM-CA were compared with those from experimental models, genetic programming (GP), model tree (M5T) and the adaptive neuro-fuzzy inference system (ANFIS). The achieved results demonstrate that the proposed SVM-CA model is able to simulate ET0 more accurately than the GP, M5T and ANFIS models. Two major indicators, namely, root mean square error (RMSE) and mean absolute error (MAE), indicated that the SVM-CA outperformed the other methods with respective reductions of 5-15% and 5-17% compared with the GP model, 12-21% and 10-22% compared with the M5T model, and 7-15% and 5-18% compared with the ANFIS model, respectively. Therefore, the proposed SVM-CA model has high potential for accurate simulation of monthly ET0 values compared with the other models.

Matched MeSH terms: Trees
Fulltext Changes to Sabah's orangutan population in recent times: 2002-2017

Simon D, Davies G, Ancrenaz M

PLoS One, 2019;14(7):e0218819.
PMID: 31314781 DOI: 10.1371/journal.pone.0218819

The Bornean orangutan is critically endangered and monitoring its population is needed to inform effective conservation management. In this paper, we present results of 2014-17 aerial nest surveys of the major orangutan populations in Sabah and compare them with baseline data produced during surveys conducted in 2002-03 using similar methods. Our results show three important points: a) by increasing the survey effort (estimated at 15-25% cover), sparsely scattered orangutan sub-populations not recorded in the previous aerial surveys were located and the accuracy of the nest count estimates is expected to improve; b) large populations in the interior forests of Sabah, occupying sustainably managed logged and unlogged forests, have been stable over 15 years and are of vital importance for the species' conservation; c) fragmented populations located in eastern Sabah, that are surrounded by extensive oil palm plantations, have declined at varying rates.

Matched MeSH terms: Trees
Fulltext PLANT CONSERVATION STATUS AND SPECIES DIVERSITY OF HUTAN LIPUR JERAM LINANG, KELANTAN

Siti Mariam, M.N, Jivitra, B.

UMT Journal of Undergraduate Research, 2019;1(4):37-50.
MyJurnal

utan Lipur Jeram Linang in Kelantan was carried out within 0.1 ha plot. All vascular plants (except lianas and epiphytes) were enumerated and identified. A total of 255 taxa representing 121 species belonging to 87 genera in 47 families were identified. Among these were 24 species endemic to Peninsular Malaysia and 47 species with medicinal values. Plants were categorized according to growth forms as follows: 67% trees, 17% shrubs, 7% palms, 6% herbs, and 3% ferns. Based on Important value index (IVI), Elateriospermum tapos, Goniothalamus umbrosus, and Monocarpia marginalis were the most dominant species whilst Rubiaceae, Arecaceae and Fabaceae were the three most diverse families. Species diversity was high based on the Shannon-Weiner index with the value of 4.38. In this study, two species from Dipterocarpaceae, which were Dipterocarpus grandiflorus and Shorea collina, were listed as Endangered (E) and Critically Endangered (CE) species respectively according to IUCN Red List. Information gained from this study showed that the forest harbored high plant diversity and endemism, so proper management is needed to protect and conserve this forest for sustainability and development.

Matched MeSH terms: Trees
Fulltext CYTOCHROME OXIDASE I (COI) DIVERGENCE ASSESSMENT OF FAMILY NEMIPTERIDAE FROM MALAYSIAN WATERS

LIEW YOU EN, SALWANI ABDULLAH, TAN MIN PAU, MAZLAN ABD GHAFFAR, ALIAS MAN, TUN NURUL AIMI MAT JAAFAR

UMT Journal of Undergraduate Research, 2019;1(1):41-48.
MyJurnal

DNA Barcoding, primarily focusing on cytochrome coxidase subunit I (COI) gene has been appraised as an effective tool for species identification. Nonetheless, species identification based on molecular approach is essential for discrimination of look-alike species. In this study, we focused on the marine fishes Family Nemipteridae, one of the commercially important group distributed within the surrounding seas of Malaysia. Some of the samples were collected during the National Demersal Trawl Survey in the Exclusive Economic Zone of East Coast Peninsular Malaysia by the Department of Fishery Malaysia. A 652bp region of COI was sequenced for 74 individuals from nine putative species. Additional 34 COIsequences from GenBank were also included in this study making the total number of samples analysed to 108 individuals. The averageKimura 2-parameter (K2P) nucleotide divergence was 0.34% among individuals within species and 6.97% within genera. All putative species formed monophyletic clades in both Neighbour-joining (NJ) and Maximum-likelihood (ML) trees. However, there was a potential misidentification in specimen identified as Nemipterus tambuloides,as the specimen did not group with their own taxa. It was genetically grouped in Nemipterus thosaporni clade. This study supports the effectiveness of COIgene in species discrimination of Family Nemipteridae.

Matched MeSH terms: Trees
Fulltext MACROFUNGI OF PULAU BIDONG

TSIA MUN KAIK, AQILAH MOHAMMAD

UMT Journal of Undergraduate Research, 2019;1(2):26-35.
MyJurnal

Studies on fungal taxonomy and fungal diversity are crucial for a better understanding of the interactions between fungi and their habitats. To date, there is no published record on macrofungal diversity in Pulau Bidong, Terengganu. Therefore, this study aimed to identify macrofungi species found with their respective substrates and to determine the macrofungal diversity in the island. The study was conducted at two different occasions and comprised of two trails near Universiti Malaysia Terengganu Research Station in Pulau Bidong, Terengganu. Collectionof fresh macrofungi was made and additional data including host information, distinctive features of each fungal sample and several environmental parameters was also recorded. Fresh specimens were later observed and identified before being dried prior to storage. Overall, 65 macrofungal species with 2 unidentified species belonging to 21 families and 34 genera were recorded. Trail A and trail B recorded diversity index of2.67 and 3.14 for Shannon Index while Simpson index recorded 0.90 and 0.94 respectively. The macrofungal diversity was dominated by family Polyporaceae while rare species discovered were from family of Tricholomataceae, Hericiaceae, Stereaceae, Schizophyllaceae, Sclerodermataceae, Dacrymycetaceae, Tremellaceae, Russulaceae and Clavulinaceae. The most common macrofungal substrates was decayed branches while other macrofungal substrates found were decayed trunks and leaves, soil,termite mounds, and living tree. In conclusion, the macrofungal species were randomlydistributed with high diversity in both trails. Therefore, it is recommended that anincrease in sampling trips, sampling efforts and areas covered be provided to increase the number of macrofungal species discovered and accuracy of diversity studies in the future.

Matched MeSH terms: Trees
Fulltext Antidiabetic, Antihyperlipidemic, Antioxidant, Anti-inflammatory Activities of Ethanolic Seed Extract of Annona reticulata L. in Streptozotocin Induced Diabetic Rats

Wen W, Lin Y, Ti Z

Front Endocrinol (Lausanne), 2019;10:716.
PMID: 31708869 DOI: 10.3389/fendo.2019.00716

Annona reticulata L. (Bullock's heart) is a pantropic tree commonly known as custard apple, which is used therapeutically for a variety of maladies. The present research was carried out to evaluate the possible protective effects of Annona reticulata L. (A. reticulata) ethanolic seed extract on an experimentally induced type 2 diabetes rat model. Male Albino Wistar rats were randomly divided into five groups with six animals in each group viz., control rats in group I, diabetic rats in group II, diabetic rats with 50 and 100 mg/kg/bw of ethanolic seed extract of A. reticulata in groups III and IV, respectively, and diabetic rats with metformin in group V. Treatment was given for 42 consecutive days through oral route by oro-gastric gavage. Administration of A. reticulata seed extract to diabetes rats significantly restored the alterations in the levels of body weight, food and water intake, fasting blood glucose (FBG), insulin levels, insulin sensitivity, HbA1c, HOMA-IR, islet area and insulin positive cells. Furthermore, A. reticulata significantly decreased the levels of triglycerides, cholesterol, LDL, and significantly increased the HDL in diabetic rats. A. reticulata effectively ameliorated the enzymatic (ALT, AST, ALP, GGT) and modification of histopathological changes in diabetic rats. The serum levels of the BUN, creatinine levels, uric acid, urine volume, and urinary protein were significantly declined with a significant elevation in CCr in diabetic rats treated with A. reticulata. MDA and NO levels were significantly reduced with an enhancement in SOD, CAT, and GPx antioxidant enzyme activities in the kidney, liver, and pancreas of diabetic rats treated with A. reticulata. Diabetic rats treated with A. reticulata have shown up-regulation in mRNA expression levels of nuclear factor erythroid 2-related factor 2 (Nrf2), NAD(P)H:quinone oxidoreductase 1 (NQO1), Heme oxygenase-1 (HO-1) and protein expression level of Nrf2 with diminution in Keap1 mRNA expression level in pancreas, kidney, and liver. From the outcome of the current results, it can be inferred that seed extract of A. reticulata exhibits a protective effect in diabetic rats through its anti-diabetic, anti-hyperlipidemic, antioxidant and anti-inflammatory effects and could be considered as a promising treatment therapy in the treatment of diabetes mellitus.

Matched MeSH terms: Trees
Fulltext Ficus carica L

Muhammad Aiman, Mohammad Rahimi, Siti Zaharah Sakimin, Mohd Fauzi, Ramlan

The Pertanika Journal of Scholarly Research Reviews, 2019;5(1):37-43.
MyJurnal

Ficus carica L. or fig is the oldest fruit tree that being cultivated by man. Grouped under genus Ficus, this species is grown widely in Mediterranean region and now being cultivated in an area with temperate or sub-temperate climate. Fig planting in Malaysia is still new, which was brought by a man as a hobby at first. Fig is a unique fruit tree as some variety can produce fruits without pollination. Contain lots of carbohydrates, essential amino acids, vitamins and minerals such potassium, fibre, calcium, iron compared to other fruits, fig have become an important source of diet to people especially in Mediterranean region since ancient time.

Matched MeSH terms: Trees
Fulltext Mangrove-Associated Fungal Communities Are Differentiated by Geographic Location and Host Structure

Lee NLY, Huang D, Quek ZBR, Lee JN, Wainwright BJ

Front Microbiol, 2019;10:2456.
PMID: 31736902 DOI: 10.3389/fmicb.2019.02456

Marine fungi on the whole remain understudied, especially in the highly diverse Southeast Asian region. We investigated the fungal communities associated with the mangrove tree Avicennia alba throughout Singapore and Peninsular Malaysia. At each sampling location, we examined ten individual trees, collecting leaves, fruits, pneumatophores, and an adjacent sediment sample from each plant. Amplicon sequencing of the fungal internal transcribed spacer 1 and subsequent analyses reveal significant differences in fungal communities collected from different locations and host structures. Mantel tests and multiple regression on distance matrices show a significant pattern of distance decay with samples collected close to one another having more similar fungal communities than those farther away. Submergence appears to drive part of the variation as host structures that are never submerged (leaves and fruits) have more similar fungal communities relative to those that are covered by water during high tide (pneumatophores and sediment). We suggest that fungi of terrestrial origins dominate structures that are not inundated by tidal regimes, while marine fungi dominate mangrove parts and sediments that are submerged by the incoming tide. Given the critical functions fungi play in all plants, and the important role they can have in determining the success of restoration schemes, we advocate that fungal community composition should be a key consideration in any mangrove restoration or rehabilitation project.

Matched MeSH terms: Trees
Machine Learning and Deep Learning Approaches in Breast Cancer Survival Prediction Using Clinical Data

Kalafi EY, Nor NAM, Taib NA, Ganggayah MD, Town C, Dhillon SK

Folia Biol. (Praha), 2019;65(5-6):212-220.
PMID: 32362304

Breast cancer survival prediction can have an extreme effect on selection of best treatment protocols. Many approaches such as statistical or machine learning models have been employed to predict the survival prospects of patients, but newer algorithms such as deep learning can be tested with the aim of improving the models and prediction accuracy. In this study, we used machine learning and deep learning approaches to predict breast cancer survival in 4,902 patient records from the University of Malaya Medical Centre Breast Cancer Registry. The results indicated that the multilayer perceptron (MLP), random forest (RF) and decision tree (DT) classifiers could predict survivorship, respectively, with 88.2 %, 83.3 % and 82.5 % accuracy in the tested samples. Support vector machine (SVM) came out to be lower with 80.5 %. In this study, tumour size turned out to be the most important feature for breast cancer survivability prediction. Both deep learning and machine learning methods produce desirable prediction accuracy, but other factors such as parameter configurations and data transformations affect the accuracy of the predictive model.

Matched MeSH terms: Decision Trees
Fulltext Ectomycorrhizal fungal communities of secondary tropical forests dominated by Tristaniopsis in Bangka Island, Indonesia

Helbert, Turjaman M, Nara K

PLoS One, 2019;14(9):e0221998.
PMID: 31498844 DOI: 10.1371/journal.pone.0221998

In Southeast Asia, primary tropical rainforests are usually dominated by ectomycorrhizal (ECM) trees belonging to Dipterocarpaceae, although arbuscular mycorrhizal trees often outcompete them after disturbances such as forest fires and clear-cutting, thus preventing dipterocarp regeneration. In some secondary tropical forests, however, potentially ECM trees belonging to Tristaniopsis (Myrtaceae) become dominant and may help ECM dipterocarp forests to recover. However, we have no information about their mycorrhizal status in these settings. In this study, we analyzed ECM fungal communities in tropical secondary forests dominated by Tristaniopsis and investigated which ECM fungal species are shared with other tropical or temperate areas. In total, 100 samples were collected from four secondary forests dominated by Tristaniopsis on Bangka Island. ECM tips in the soil samples were subjected to molecular analyses to identify both ECM and host species. Based on a >97% ITS sequence similarity threshold, we identified 56 ECM fungal species dominated by Thelephoraceae, Russulaceae, and Clavulinaceae. Some of the ECM fungal species were shared between dominant Tristaniopsis and coexisting Eucalyptus or Quercus trees, including 5 common to ECM fungi recorded in a primary mixed dipterocarp forest at Lambir Hill, Malaysia. In contrast, no ECM fungal species were shared with other geographical regions, even with Tristaniopsis in New Caledonia. These results imply that secondary tropical forests dominated by Tristaniopsis harbor diverse ECM fungi, including those that inhabit primary dipterocarp forests in the same geographical region. They may function as refugia for ECM fungi, given that dipterocarp forests are disappearing quickly due to human activity.

Matched MeSH terms: Trees
Fulltext Linkages between Chiropteran diversity and ecosystem services for sustainable fragmented forest conservation

Fakhrul-Hatta SNN, Nelson BR, Shafie NJ, Zahidin MA, Abdullah MT

Data Brief, 2018 Dec;21:2089-2094.
PMID: 30533456 DOI: 10.1016/j.dib.2018.11.058

This data article informs about Chiropteran diversity, new records, ecosystem services and possible pathogen carriers in fragmented forests (sub-divided by utility corridors, man-made structures, untouched and secondary plantations) within districts Setiu (Setiu Research Station), Hulu Terengganu (Saok and Lasir waterfalls) and Besut (Gunung Tebu Forest Reserve) of state Terengganu, Peninsular Malaysia. These bats were captured using harp traps and mist nets that were set 10 m apart across flyways, streams and less cluttered trees in the 50 m × 50 m transect zones (identified at each site). All animals were distinguished by morphology and gender before their release at the site of capture. The data comprise of five bat family groups Hipposideridae, Megadermatidae, Pteropodidae, Rhinolophidae and Vespertilionidae. It is interesting to note that untouched Saok Waterfalls is home to wide variety of bats listed (68.8%), followed by secondary forests of Gunung Tebu Forest Reserve (24.8%), untouched Lasir Waterfalls (4.8%) and lastly, Setiu Research Station as least favored (1.6%). Chiroptera like Cynopterus brachyotis (n = 23, 37.7%), Hipposideros bicolor (n = 6, 9.8%) and Scotophilus kuhli (n = 6, 9.8%) were most dominant in the checklist whereas Hipposideros armiger, Murina suilla and Scotophilus kuhlii are new data records in the fragmented forests of Terengganu. The data were interpret into Shannon, Simpson, Margalef, Menhinik and Evenness indices to individually or collectively distinguish chiropteran variety in Terengganu State whereas weight-forearm length (W/FA) informs about chiropteran Body Condition Index (-0.25 to 0.25). The function of bats were also identified to distinguish service providers (pollination and forests regeneration) and zoonotic pathogen carriers (in particular to Leptospira bacteria, Nipah virus and Sindbis virus).

Matched MeSH terms: Trees
Pseudo-nitzschia nanaoensis sp. nov. (Bacillariophyceae) from the Chinese coast of the South China Sea

Li Y, Dong HC, Teng ST, Bates SS, Lim PT

J Phycol, 2018 12;54(6):918-922.
PMID: 30270437 DOI: 10.1111/jpy.12791

Pseudo-nitzschia nanaoensis sp. nov. is described from waters around Nan'ao Island (South China Sea), using morphological data and molecular evidence. This species is morphologically most similar to P. brasiliana, but differs by a denser arrangement of fibulae, interstriae, and poroids, as well as by the structure of the valvocopula and the narrow second band. Pseudo-nitzschia nanaoensis constitutes a monophyletic lineage and is well differentiated from other species on the LSU and ITS2 sequence-structure trees. Pseudo-nitzschia nanaoensis makes up the basal node on the LSU tree, and forms a sister clade with a group of P. pungens and P. multiseries on the ITS2 tree. The ability of cultured strains to produce domoic acid was assessed, including its possible induction by the presence of a copepod and brine shrimp, by liquid chromatography-tandem mass spectrometry. However, no strains showed detectable domoic acid.

Matched MeSH terms: Trees
Non-volant small mammal data from fragmented forests in Terengganu State

Khalib NKA, Shafie NJ, Basri HH, Nelson BR, Abdullah MT

Data Brief, 2018 Dec;21:1514-1520.
PMID: 30480062 DOI: 10.1016/j.dib.2018.10.061

This data article is about non-volant small mammal (squirrel, rat and tree shrew) capture from fragmented forest understories within sub-urban areas of Setiu (Peladang Agro Resort and Setiu Wetland Research Station) and inhabited areas of Hulu Terengganu (Saok and Lasir waterfalls) that are situated in Terengganu State, Peninsular Malaysia. Fruits like banana and oil palm were individually placed into each cage before the cages were fastened onto three to five meter height tree branches. The traps were also spatially distributed about ten meters from each other. Under this installation, fifty baited traps were used during the twenty-four nights of sample collection. All animals caught were distinguished by morphology and released at the same location it was caught. The understory data comprise of seven non-volant mammal species from family groups Sciuridae, Muridae and Tupaiidae. Overall, Callosciurus notatus (n = 17, 39%) were dominant in the capture pool from all sites. Comparatively, Sundascriurus tenuis (n = 2, 4%) and Rattus rattus (n = 4, 9.3%) were restricted to Saok Waterfalls and Setiu Wetland. Banana and oil palm fruits did not attract any small mammals during the Lasir Waterfall (Hulu Terengganu) survey. All data were interpret into Shannon, Simpson, Margalef, Menhinik and Evenness indices to individually or collectively distinguish small mammal variety in Terengganu State.

Matched MeSH terms: Trees
Identification and expression profiling of genes governing lignin biosynthesis in Casuarina equisetifolia L

Vikashini B, Shanthi A, Ghosh Dasgupta M

Gene, 2018 Nov 15;676:37-46.
PMID: 30201104 DOI: 10.1016/j.gene.2018.07.012

Casuarina equisetifolia L. is an important multi-purpose, fast growing and widely planted tree species native to tropical and subtropical coastlines of Australia, Southeast Asia, Malaysia, Melanesia, Polynesia and New Caledonia. It is a nitrogen-fixing tree mainly used for charcoal making, construction poles, landscaping, timber, pulp, firewood, windbreaks, shelterbelts, soil erosion and sand dune stabilization. Casuarina wood is presently used for paper and pulp production. Raw material with reduced lignin is highly preferred to increase the pulp yield. Hence, understanding the molecular regulation of wood formation in this tree species is vital for selecting industrially suitable phenotypes for breeding programs. The lignin biosynthetic pathway has been extensively studied in tree species like Eucalypts, poplars, pines, Picea, Betula and Acacia sp. However, studies on wood formation at molecular level is presently lacking in casuarinas. Hence, in the present study, the transcriptome of the developing secondary tissues of 15 years old Casuarina equiseitfolia subsp. equisetifolia was sequenced, de novo assembled, annotated and mapped to functional pathways. Transcriptome sequencing generated a total of 26,985 transcripts mapped to 31 pathways. Mining of the annotated data identified nine genes involved in lignin biosynthesis pathway and relative expression of the transcripts in four tissues including scale-like leaves, needle-like brachlets, wood and root were documented. The expression of CeCCR1 and CeF5H were found to be significantly high in wood tissues, while maximum expression of CeHCT was documented in stem. Additionally, CeTUBA and CeH2A were identified as the most stable reference transcript for normalization of qRT-PCR data in C. equisetifolia. The present study is the first wood genomic resource in C. equisetifolia, which will be valuable for functional genomics research in this genus.

Matched MeSH terms: Trees/genetics
Fulltext A predictive method for hepatitis disease diagnosis using ensembles of neuro-fuzzy technique

Nilashi M, Ahmadi H, Shahmoradi L, Ibrahim O, Akbari E

J Infect Public Health, 2018 10 04;12(1):13-20.
PMID: 30293875 DOI: 10.1016/j.jiph.2018.09.009

BACKGROUND: Hepatitis is an inflammation of the liver, most commonly caused by a viral infection. Supervised data mining techniques have been successful in hepatitis disease diagnosis through a set of datasets. Many methods have been developed by the aids of data mining techniques for hepatitis disease diagnosis. The majority of these methods are developed by single learning techniques. In addition, these methods do not support the ensemble learning of the data. Combining the outputs of several predictors can result in improved accuracy in classification problems. This study aims to propose an accurate method for the hepatitis disease diagnosis by taking the advantages of ensemble learning.
METHODS: We use Non-linear Iterative Partial Least Squares to perform the data dimensionality reduction, Self-Organizing Map technique for clustering task and ensembles of Neuro-Fuzzy Inference System for predicting the hepatitis disease. We also use decision trees for the selection of most important features in the experimental dataset. We test our method on a real-world dataset and present our results in comparison with the latest results of previous studies.
RESULTS: The results of our analyses on the dataset demonstrated that our method performance is superior to the Neural Network, ANFIS, K-Nearest Neighbors and Support Vector Machine.
CONCLUSIONS: The method has potential to be used as an intelligent learning system for hepatitis disease diagnosis in the healthcare.

Matched MeSH terms: Decision Trees
Identity of the tree-spider crab, Parasesarma leptosoma (Hilgendorf, 1869 (Decapoda: Brachyura: Sesarmidae), with descriptions of seven new species from the Western Pacific

Li JJ, Rahayu DL, Ng PKL

Zootaxa, 2018 Sep 19;4482(3):451-490.
PMID: 30313809 DOI: 10.11646/zootaxa.4482.3.2

The identity of the tree-spider crab, Parasesarma leptosoma (Hilgendorf, 1869) (family Sesarmidae), which is believed to be widely distributed in the Indo-West Pacific, is reassessed and shown to be a species-complex with nine species, seven of which are here described as new. Parasesarma leptosoma sensu stricto is now restricted to South and East Africa; and P. limbense (Rathbun, 1914) from Sulawesi, which had been regarded as a junior synonym, is here recognized as a valid species. The following species are described as new: P. gecko n. sp. from Vanuatu, Fiji, Guam and Japan; P. macaco n. sp. from Taiwan and the Philippines; P. kui n. sp. from Taiwan; P. parvulum n. sp. from the Philippines; P. gracilipes n. sp. from Indonesian Papua; P. purpureum n. sp. from Malaysia; and P. tarantula n. sp. from Sulawesi, Indonesia. The nine species of the Parasesarma leptosoma species-complex can be separated by the different shapes of their carapaces, the form of the dactylar tubercles on the male chelipeds, proportions of their ambulatory legs and the structure of the male first gonopod.

Matched MeSH terms: Trees*
GIS-based groundwater potential analysis using novel ensemble weights-of-evidence with logistic regression and functional tree models

Chen W, Li H, Hou E, Wang S, Wang G, Panahi M, et al.

Sci Total Environ, 2018 Sep 01;634:853-867.
PMID: 29653429 DOI: 10.1016/j.scitotenv.2018.04.055

The aim of the current study was to produce groundwater spring potential maps using novel ensemble weights-of-evidence (WoE) with logistic regression (LR) and functional tree (FT) models. First, a total of 66 springs were identified by field surveys, out of which 70% of the spring locations were used for training the models and 30% of the spring locations were employed for the validation process. Second, a total of 14 affecting factors including aspect, altitude, slope, plan curvature, profile curvature, stream power index (SPI), topographic wetness index (TWI), sediment transport index (STI), lithology, normalized difference vegetation index (NDVI), land use, soil, distance to roads, and distance to streams was used to analyze the spatial relationship between these affecting factors and spring occurrences. Multicollinearity analysis and feature selection of the correlation attribute evaluation (CAE) method were employed to optimize the affecting factors. Subsequently, the novel ensembles of the WoE, LR, and FT models were constructed using the training dataset. Finally, the receiver operating characteristic (ROC) curves, standard error, confidence interval (CI) at 95%, and significance level P were employed to validate and compare the performance of three models. Overall, all three models performed well for groundwater spring potential evaluation. The prediction capability of the FT model, with the highest AUC values, the smallest standard errors, the narrowest CIs, and the smallest P values for the training and validation datasets, is better compared to those of other models. The groundwater spring potential maps can be adopted for the management of water resources and land use by planners and engineers.

Matched MeSH terms: Trees
Climate sensitive size-dependent survival in tropical trees

Johnson DJ, Needham J, Xu C, Massoud EC, Davies SJ, Anderson-Teixeira KJ, et al.

Nat Ecol Evol, 2018 09;2(9):1436-1442.
PMID: 30104751 DOI: 10.1038/s41559-018-0626-z

Survival rates of large trees determine forest biomass dynamics. Survival rates of small trees have been linked to mechanisms that maintain biodiversity across tropical forests. How species survival rates change with size offers insight into the links between biodiversity and ecosystem function across tropical forests. We tested patterns of size-dependent tree survival across the tropics using data from 1,781 species and over 2 million individuals to assess whether tropical forests can be characterized by size-dependent life-history survival strategies. We found that species were classifiable into four 'survival modes' that explain life-history variation that shapes carbon cycling and the relative abundance within forests. Frequently collected functional traits, such as wood density, leaf mass per area and seed mass, were not generally predictive of the survival modes of species. Mean annual temperature and cumulative water deficit predicted the proportion of biomass of survival modes, indicating important links between evolutionary strategies, climate and carbon cycling. The application of survival modes in demographic simulations predicted biomass change across forest sites. Our results reveal globally identifiable size-dependent survival strategies that differ across diverse systems in a consistent way. The abundance of survival modes and interaction with climate ultimately determine forest structure, carbon storage in biomass and future forest trajectories.

Matched MeSH terms: Trees*
Fulltext Spatial scale changes the relationship between beta diversity, species richness and latitude

Sreekar R, Katabuchi M, Nakamura A, Corlett RT, Slik JWF, Fletcher C, et al.

R Soc Open Sci, 2018 Sep;5(9):181168.
PMID: 30839691 DOI: 10.1098/rsos.181168

The relationship between β-diversity and latitude still remains to be a core question in ecology because of the lack of consensus between studies. One hypothesis for the lack of consensus between studies is that spatial scale changes the relationship between latitude and β-diversity. Here, we test this hypothesis using tree data from 15 large-scale forest plots (greater than or equal to 15 ha, diameter at breast height ≥ 1 cm) across a latitudinal gradient (3-30o) in the Asia-Pacific region. We found that the observed β-diversity decreased with increasing latitude when sampling local tree communities at small spatial scale (grain size ≤0.1 ha), but the observed β-diversity did not change with latitude when sampling at large spatial scales (greater than or equal to 0.25 ha). Differences in latitudinal β-diversity gradients across spatial scales were caused by pooled species richness (γ-diversity), which influenced observed β-diversity values at small spatial scales, but not at large spatial scales. Therefore, spatial scale changes the relationship between β-diversity, γ-diversity and latitude, and improving sample representativeness avoids the γ-dependence of β-diversity.

Matched MeSH terms: Trees
Fatal penetrating neck injury due to defective airbag inflator

Jothee S, Shafie MS, Mohd Nor F

Forensic Sci Int, 2018 Aug 31.
PMID: 30217665 DOI: 10.1016/j.forsciint.2018.08.038

We present a case of a fatal motor vehicle collision of a 22-year-old car driver, who died at the scene after losing control of his car, and subsequently collided with a tree by the roadside. The subsequent autopsy revealed penetrating injuries on the neck, severing the larynx, carotid artery, jugular vein and fracturing the cervical vertebrae. Internal examination showed the offending material to be a semi-cylindrical metal fragment, which had lodged within the paravertebral muscle. Examination of the car with the authorities found that the metal fragment originated from a defective airbag booster cannister, which shattered upon deployment.

Matched MeSH terms: Trees

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