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Fulltext Bacterial Larvicide, Bacillus thuringiensis israelensis Strain AM 65-52 Water Dispersible Granule Formulation Impacts Both Dengue Vector, Aedes aegypti (L.) Population Density and Disease Transmission in Cambodia

Setha T, Chantha N, Benjamin S, Socheat D

PLoS Negl Trop Dis, 2016 09;10(9):e0004973.
PMID: 27627758 DOI: 10.1371/journal.pntd.0004973

A multi-phased study was conducted in Cambodia from 2005-2011 to measure the impact of larviciding with the bacterial larvicide, Bacillus thuringiensis israelensis (Bti), a water dispersible granule (WG) formulation on the vector, Aedes aegypti (L.) and the epidemiology. In our studies, all in-use containers were treated at 8 g/1000 L, including smaller containers and animal feeders which were found to contribute 23% of Ae aegypti pupae. The treated waters were subjected to routine water exchange activities. Pupal production was suppressed by an average 91% for 8 weeks. Pupal numbers continued to remain significantly lower than the untreated commune (UTC) for 13 weeks post treatment in the peak dengue vector season (p<0.05). Suppression of pupal production was supported by very low adult numbers in the treated commune. An average 70% of the household harbored 0-5 Ae aegypti mosquitoes per home for 8 weeks post treatment, but in the same period of time >50% of the household in the UTC harbored ≥11 mosquitoes per home. The adult population continued to remain at significantly much lower numbers in the Bti treated commune than in the UTC for 10-12 weeks post treatment (p<0.05). In 2011, a pilot operational program was evaluated in Kandal Province, a temephos resistant site. It was concluded that 2 cycles of Bti treatment in the 6 months monsoon season with complete coverage of the target districts achieved an overall dengue case reduction of 48% in the 6 treated districts compared to the previous year, 2010. Five untreated districts in the same province had an overwhelming increase of 352% of dengue cases during the same period of time. The larvicide efficacy, treatment of all in-use containers at the start of the monsoon season, together with treatment coverage of entire districts interrupted disease transmission in the temephos resistant province.

Matched MeSH terms: Seasons
Fulltext Ball possession of a successful team (Johor Darul Ta’zim FC) in Malaysia Super League 2015: a case study

Miswan, M.S., Aznan, E.A.M., Ismail, Z., Jamaludin, M., Mohd Kassim, A.F.

Movement Health & Exercise, 2018;7(2):117-126.
MyJurnal

Ability to possess ball during football matches are link to success. Domination of Johor Darul Ta’zim FC (JDT FC) in recent years in Malaysia Super League impressed many. The aim of this study was to compare the performance between JDT FC and their opponents in Malaysia Super League 2015 season. Successful and unsuccessful passes, ball possession rates, attempt on goal, shot on target, and goal scored were selected as Performance Indicator (P.I) in this study. Twelve matches from Malaysia Super League (MSL) season 2015 were selected. The video of 12 matches was obtained from Media Prima Sdn. Bhd., www.youtube.com and live recordings. Longo Match 1.0 match analysis software was used for post-coding. Kolmogorov-Smirnov Z was used to analyses the differences while Spearman's rho correlation test was utilized to determine the correlation. Percentage of successful passes (p=0.034), ball possessions rate (p=0.000), and goal scored (p=0.002) were significantly different between JDT FC and their opponents. There were also positive correlations between possessions and all variables except for unsuccessful passes. This study concluded that in Malaysian football matches, high percentage of successful passes, and high rate of ball possessions influenced total shot in football game.

Matched MeSH terms: Seasons
Barrier spraying at the Kelantan side of the Thai-Malaysia border

Huehne WH

J Trop Med Hyg, 1971 May;74(5):106-9.
PMID: 5580454
Matched MeSH terms: Seasons
Baseline study of methane emission from anaerobic ponds of palm oil mill effluent treatment

Yacob S, Ali Hassan M, Shirai Y, Wakisaka M, Subash S

Sci Total Environ, 2006 Jul 31;366(1):187-96.
PMID: 16125215

The world currently obtains its energy from the fossil fuels such as oil, natural gas and coal. However, the international crisis in the Middle East, rapid depletion of fossil fuel reserves as well as climate change have driven the world towards renewable energy sources which are abundant, untapped and environmentally friendly. Malaysia has abundant biomass resources generated from the agricultural industry particularly the large commodity, palm oil. This paper will focus on palm oil mill effluent (POME) as the source of renewable energy from the generation of methane and establish the current methane emission from the anaerobic treatment facility. The emission was measured from two anaerobic ponds in Felda Serting Palm Oil Mill for 52 weeks. The results showed that the methane content was between 35.0% and 70.0% and biogas flow rate ranged between 0.5 and 2.4 L/min/m(2). Total methane emission per anaerobic pond was 1043.1 kg/day. The total methane emission calculated from the two equations derived from relationships between methane emission and total carbon removal and POME discharged were comparable with field measurement. This study also revealed that anaerobic pond system is more efficient than open digesting tank system for POME treatment. Two main factors affecting the methane emission were mill activities and oil palm seasonal cropping.

Matched MeSH terms: Seasons
Baseline study of methane emission from open digesting tanks of palm oil mill effluent treatment

Yacob S, Hassan MA, Shirai Y, Wakisaka M, Subash S

Chemosphere, 2005 Jun;59(11):1575-81.
PMID: 15894045

Anthropogenic release of greenhouse gases, especially CO2 and CH4 has been recognized as one of the main causes of global warming. Several measures under the Kyoto Protocol 1997 have been drawn up to reduce the greenhouse gases emission. One of the measures is Clean Development Mechanisms (CDM) that was created to enable developed countries to cooperate with developing countries in emission reduction activities. In Malaysia, palm oil industry particularly from palm oil mill effluent (POME) anaerobic treatment has been identified as an important source of CH4. However, there is no study to quantify the actual CH4 emission from the commercial scale wastewater treatment facility. Hence, this paper shall address the CH4 emission from the open digesting tanks in Felda Serting Hilir Palm Oil Mill. CH4 emission pattern was recorded for 52 weeks from 3600 m3 open digesting tanks. The findings indicated that the CH4 content was between 13.5% and 49.0% which was lower than the value of 65% reported earlier. The biogas flow rate ranged between 0.8l min(-1)m(-2) and 9.8l min(-1)m(-2). Total CH4 emission per open digesting tank was 518.9 kgday(-1). Relationships between CH4 emission and total carbon removal and POME discharged were also discussed. Fluctuation of biogas production was observed throughout the studies as a result of seasonal oil palm cropping, mill activities, variation of POME quality and quantity discharged from the mill. Thus only through long-term field measurement CH4 emission can be accurately estimated.

Matched MeSH terms: Seasons
Biochemical composition and fatty acid content of zooplankton from tropical lagoon for larval rearing

Lokman HS

Arch Int Physiol Biochim Biophys, 1993 Sep-Oct;101(5):253-6.
PMID: 7508281

Zooplankton samples were collected from the indigenous tropical brackish water lagoon during the wet monsoon (January and February 1990) and the dry monsoon (April and May 1990). The dominant copepod species in the zooplankton community comprising of Oithona sp (especially O. nana and O. robusta) accounted for more than 70% of the zooplankton in January and was gradually replaced by other zooplanktonic species later in the dry season. The lipid contents in zooplankton varied from 0.18 to 1.04% wet weight or 1.14 to 5.92% dry weight respectively. The major fatty acid contents of the zooplankton showed high concentration of 14:0, 16:0, 18:1, 20:5 omega 3 and 22:6 omega 3 especially in the wet season. It also contained high omega-3 highly unsaturated fatty acid series necessary for the growth of commercial fish larvae. It has a better food value than the normally use food organism, brine shrimp; thus reflecting its potential use as food organism for fish larval rearing.

Matched MeSH terms: Seasons
Fulltext Biodiversity, seasonal abundance, and distribution of blackflies (Diptera: Simuliidae) in six different regions of Thailand

Srisuka W, Takaoka H, Otsuka Y, Fukuda M, Thongsahuan S, Taai K, et al.

Parasit Vectors, 2017 Nov 21;10(1):574.
PMID: 29157269 DOI: 10.1186/s13071-017-2492-y

BACKGROUND: Blackflies are an important medical and veterinary group of small blood-sucking insects. Ninety-three blackfly species have been reported in Thailand. However, information on their biodiversity and population dynamics in each region is lacking. The main aim of this study was to assess the regional biodiversity, seasonal abundance and distribution of blackflies in six eco-geographically different regions in the country.
METHODS: Blackfly larvae and pupae were sampled monthly from 58 sites between May 2011 and April 2013. Diversity parameters, seasonal abundance, regional distribution and frequency of species occurrence in stream sites were analyzed.
RESULTS: A total of 19,456 mature larvae representing 57 species, and belonging to six subgenera in the genus Simulium Latreille (s.l.), were found. The five predominant taxa were S. fenestratum (8.6%), the S. asakoae complex (8.3%), S. nakhonense (7.5%), the S. siamense complex (7.4%) and the S. doipuiense complex (6.7%). The most frequent taxa at all sites were the S. asakoae complex (84.5%), followed by S. fenestratum (82.8%), the S. siamense complex (75.9%), S. decuplum (60.3%), S. nakhonense (58.6%) and the S. tani complex (48.3%). The richness of regional species was highest (40 species) in the north and predominated in the cold season. However, blackflies in the south predominated during the hot season. The highest numbers of blackflies collected from central, northeastern, eastern and western regions of the country were observed in the rainy season. Overall, the mean number of blackflies collected across the six regions during the rainy and cold season had no statistically significant difference, but it differed significantly in the hot season.
CONCLUSIONS: Blackflies in Thailand were surveyed in all three seasons across six geographical regions. These findings demonstrated that blackfly communities at each stream site varied with seasonality, and the regional relative abundance of blackflies differed markedly in the hot season. It was also found that the occurrence and distribution of blackflies in each region were associated strongly with elevation.

Matched MeSH terms: Seasons
Biogeochemical and physical drivers of hypoxia in a tropical embayment (Brunei Bay)

Hee YY, Weston K, Suratman S, Akhir MF, Latif MT, Valliyodan S

Environ Sci Pollut Res Int, 2023 May;30(24):65351-65363.
PMID: 37081368 DOI: 10.1007/s11356-023-26948-9

Dissolved oxygen is an ecologically critical variable with the prevalence of hypoxia one of the key global anthropogenic issues. A study was carried out to understand the causes of low dissolved oxygen in Brunei Bay, northwest Borneo. Hypoxia was widespread in bottom waters in the monsoonal dry season with dissolved oxygen

Matched MeSH terms: Seasons
Fulltext Biological Activities of Snowdrop (Galanthus spp., Family Amaryllidaceae)

Kong CK, Low LE, Siew WS, Yap WH, Khaw KY, Ming LC, et al.

Front Pharmacol, 2020;11:552453.
PMID: 33679383 DOI: 10.3389/fphar.2020.552453

Snowdrop is an iconic early spring flowering plant of the genus Galanthus (Amaryllidaceae). Galanthus species (Galanthus spp.) are economically important plants as ornaments. Galanthus spp has gained significance scientific and commercial interest due to the discovery of Galanthamine as symptomatic treatment drug for Alzhiermer disease. This review aims to discuss the bioactivities of Galanthus spp including anticholinesterase, antimicrobial, antioxidant and anticancer potential of the extracts and chemical constituents of Galanthus spp. This review highlights that Galanthus spp. as the exciting sources for drug discovery and nutraceutical development.

Matched MeSH terms: Seasons
Biological Control of Diamondback Moth, Plutella xylostella (L.),Using Parasitoids and Bacteria: A Review

Idris A.B., Norhayati Abdul Mukti

Sains Malaysiana, 1997;26.

Resistance of diamondback moth (DBM), Plutella xylostela (L), to coventional pesticides and concerns about environmental quality have lead to increased worldwide efforts to develop viable biocontrol methods for DBM. The success of using parasitoids, especially larval parasitoids like Diadegma, Cotesia and Microplitis species for controlling DBM have been reported in several countries. These larval parasitoids of DBM are commonly found in the field. Diadegma semiclausum (=eucerophaga) Hellen is the major parasitoid of DBM in Europe and Asia, while Diadegma insulare (Cresson) are predominates in the Americas. To date, the bacterium, Bacillus thuringiensis Berliner subspecies kurstaki, has been the most widely used DBM pathogen. Although it is environment friendly pesticides, its effectiveness always vary with weather, field location and frequency of application per season. These are the main factors that contribute to the slow acceptance of B.thuringiensis by the cabbage growers worldwide. Because of this many studies have been done to improve its efficacay and persistence in the field. This paper provides an overview of the current status of these agents for use in controlling DBM and suggest research that is needed to improve the usefulness of these biocontrol agents and to maximize their impact on the DBM management in the future.
Ketahanan rama-rama belakang-intan (diamondback moth), Plutella xylostella (L.), kepada semua racun-racun perosak yang biasa digunakan untuk mengawalnya dan keprihatinan terhadap kualiti alam sekitar telah menyebabkan bertambahnya usaha mencari beberapa kaedah kawalan biologi rama-rama ini di seluruh dunia. Kejayaan menggunakan parasitoids, terutamanya parasitoid larva seperti spesies Diadegma, Cotesia dan Microplitis bagi kawalan serangga ini telah dilaporkan oleh beberapa negara. Parasitoid-parasitoid larva ini mudah didapati di lapangan. Diadegma semiclausum (=eucerophaga) Hellen adalah merupakan parasitoid utama di Eropah dan Asia, sementara Diadegma insulare (Cresson) predominen di benua America. Sehingga kini, bakteria Bacillus thuringiensis Berliner subspesies kurstaki, adalah sejenis patogen serangga yang digunakan secara meluas untuk mengawal rama-rama tersebut. Walaupun B. thuringiensis adalah sejenis racun makhluk perosak yang tidak mencemari alam sekitar, tahap keberkesanan tindakannya adalah kerap berubah-ubah mengikut perubahan cuaca, lokasi lapangan dan kekerapan penggunaannya. Ini adalah merupakan faktor-faktor penting yang menyebabkan kelambatan penerimaannya oleh penanam-penanam kobis di merata dunia. Oleh sebab inilah banyak kajian telah dan sedang dijalankan bagi memperbaiki tahap keberkesanan dan persistentnya di lapangan. Kertas ini disedia bagi memperihalkan status penggunaan kedua-dua jenis agen kawalan biologi disamping mengesyurkan penyelidikan yang perlu dibuat untuk mempertingkatkan kegunaan dan memaksimumkan dampaknya dalam pengurusan rama-rama ini masa akan datang.

Matched MeSH terms: Seasons
Fulltext Biomass and Habitat Characteristics of Epiphytic Macroalgae in the Sibuti Mangroves, Sarawak, Malaysia

Isa HM, Kamal AH, Idris MH, Rosli Z, Ismail J

Trop Life Sci Res, 2017 Jan;28(1):1-21.
PMID: 28228913 MyJurnal DOI: 10.21315/tlsr2017.28.1.1

Mangroves support diverse macroalgal assemblages as epibionts on their roots and tree trunks. These algae provide nutrients to the primary consumers in the aquatic food web and have been reported to be substantial contributors to marine ecosystems. The species diversity, biomass, and habitat characteristics of mangrove macroalgae were investigated at three stations in the Sibuti mangrove estuary, Sarawak, Malaysia, from November 2012 to October 2013. Three groups of macroalgae were recorded and were found to be growing on mangrove prop roots, namely Rhodophyta (Caloglossa ogasawaraensis, Caloglossa adhaerens, Caloglossa stipitata, Bostrychia anomala, and Hypnea sp.), Chlorophyta (Chaetomorpha minima and Chaetomorpha sp.), and Phaeophyta (Dictyota sp.). The biomass of macroalgae was not influenced (p>0.05) by the season in this mangrove forest habitat. The macroalgal species Hypnea sp. contributed the highest biomass at both Station 1 (210.56 mg/cm(2)) and Station 2 (141.72 mg/cm(2)), while the highest biomass was contributed by B. anomala (185.89 mg/cm(2)) at Station 3. This study shows that the species distribution and assemblages of mangrove macroalgae were influenced by environmental parameters such as water nutrients, dissolved solids, and salinity in the estuarine mangrove habitats of Sibuti, Sarawak.

Matched MeSH terms: Seasons
Bleeding manifestations of dengue haemorrhagic fever in Malaysia

George R, Duraisamy G

Acta Trop, 1981 Mar;38(1):71-8.
PMID: 6111919

Analysis of the bleeding manifestations of 130 cases of dengue haemorrhagic fever admitted into the Children's ward of the General Hospital, Kuala Lumpur from May 1973 to September 1978 has been done. Petechial skin rash, epistaxis and gum bleeding were seen most commonly in mild and moderately severe cases. However, blood stained gastric aspirates, and severe haematemesis were seen in severe or very severe cases. Though with better vector control and preventive measures, a marked reduction in the incidence of the cases has been noted, severe cases were seen with symptoms of shock and gastrointestinal bleeding. These symptoms carried a bad prognosis. Among 15 children that died 10 had gastrointestinal bleeding and 2 had a disseminated intravascular coagulation defect. Lymphocytosis with atypical lymphocytes, low platelet count, low reticulocyte count and raised packed cell volume were the main haematological features seen in all these cases. All these features reverted to normal within a week. Mild evidence of disseminated intravascular coagulation was seen in a number of cases, but severe features were seen only in four. Two cases improved as a result of heparin therapy.

Matched MeSH terms: Seasons
Fulltext Borneo coral reefs subject to high sediment loads show evidence of resilience to various environmental stressors

Browne N, Braoun C, McIlwain J, Nagarajan R, Zinke J

PeerJ, 2019;7:e7382.
PMID: 31428541 DOI: 10.7717/peerj.7382

For reefs in South East Asia the synergistic effects of rapid land development, insufficient environmental policies and a lack of enforcement has led to poor water quality and compromised coral health from increased sediment and pollution. Those inshore turbid coral reefs, subject to significant sediment inputs, may also inherit some resilience to the effects of thermal stress and coral bleaching. We studied the inshore turbid reefs near Miri, in northwest Borneo through a comprehensive assessment of coral cover and health in addition to quantifying sediment-related parameters. Although Miri's Reefs had comparatively low coral species diversity, dominated by massive and encrusting forms of Diploastrea, Porites, Montipora, Favites, Dipsastrea and Pachyseris, they were characterized by a healthy cover ranging from 22 to 39%. We found a strong inshore to offshore gradient in hard coral cover, diversity and community composition as a direct result of spatial differences in sediment at distances <10 km. As well as distance to shore, we included other environmental variables like reef depth and sediment trap accumulation and particle size that explained 62.5% of variation in benthic composition among sites. Miri's reefs showed little evidence of coral disease and relatively low prevalence of compromised health signs including bleaching (6.7%), bioerosion (6.6%), pigmentation response (2.2%), scars (1.1%) and excessive mucus production (0.5%). Tagged colonies of Diploastrea and Pachyseris suffering partial bleaching in 2016 had fully (90-100%) recovered the following year. There were, however, seasonal differences in bioerosion rates, which increased five-fold after the 2017 wet season. Differences in measures of coral physiology, like that of symbiont density and chlorophyll a for Montipora, Pachyseris and Acropora, were not detected among sites. We conclude that Miri's reefs may be in a temporally stable state given minimal recently dead coral and a limited decline in coral cover over the last two decades. This study provides further evidence that turbid coral reefs exposed to seasonally elevated sediment loads can exhibit relatively high coral cover and be resilient to disease and elevated sea surface temperatures.

Matched MeSH terms: Seasons
Carbon allocation in a Bornean tropical rainforest without dry seasons

Katayama A, Kume T, Komatsu H, Saitoh TM, Ohashi M, Nakagawa M, et al.

J Plant Res, 2013 Jul;126(4):505-15.
PMID: 23283581 DOI: 10.1007/s10265-012-0544-0

To clarify characteristics of carbon (C) allocation in a Bornean tropical rainforest without dry seasons, gross primary production (GPP) and C allocation, i.e., above-ground net primary production (ANPP), aboveground plant respiration (APR), and total below-ground carbon flux (TBCF) for the forest were examined and compared with those from Amazonian tropical rainforests with dry seasons. GPP (30.61 MgC ha(-1) year(-1), eddy covariance measurements; 34.40 MgC ha(-1) year(-1), biometric measurements) was comparable to those for Amazonian rainforests. ANPP (6.76 MgC ha(-1) year(-1)) was comparable to, and APR (8.01 MgC ha(-1) year(-1)) was slightly lower than, their respective values for Amazonian rainforests, even though aboveground biomass was greater at our site. TBCF (19.63 MgC ha(-1) year(-1)) was higher than those for Amazonian forests. The comparable ANPP and higher TBCF were unexpected, since higher water availability would suggest less fine root competition for water, giving higher ANPP and lower TBCF to GPP. Low nutrient availability may explain the comparable ANPP and higher TBCF. These data show that there are variations in C allocation patterns among mature tropical rainforests, and the variations cannot be explained solely by differences in soil water availability.

Matched MeSH terms: Seasons
Case Report: Paralytic Shellfish Poisoning in Sabah, Malaysia

Suleiman M, Jelip J, Rundi C, Chua TH

Am J Trop Med Hyg, 2017 Dec;97(6):1731-1736.
PMID: 29016314 DOI: 10.4269/ajtmh.17-0589

During the months of January-February and May-June 2013 coinciding with the red tide occurrence in Kota Kinabalu, Sabah, Malaysia, six episodes involving 58 cases of paralytic shellfish poisoning (PSP) or saxitoxin (STX) poisoning and resulting in four deaths were reported. Many of them were intoxicated from consuming shellfish purchased from the markets, whereas others were intoxicated from eating shellfish collected from the beach. Levels of STX in shellfish collected from the affected areas were high (mean 2,920 ± 780 and 360 ± 140 µg STX equivalents/100 g shellfish meat respectively for the two periods). The count of toxic dinoflagellates (Pyrodinium bahamense var compressum) of the sea water sampled around the coast was also high (mean 34,200 ± 10,300 cells/L). Species of shellfish containing high levels of STX were Atrina fragilis, Perna viridis, and Crassostrea belcheri. The age of victims varied from 9 to 67 years. Symptoms presented were typical of PSP, such as dizziness, numbness, vomiting, and difficulty in breathing. Recommended steps to prevent or reduce PSP in future red tide season include better monitoring of red tide occurrence, regular sampling of shellfish for determination of STX level, wider dissemination of information on the danger of eating contaminated shellfish among the communities, fishermen, and fishmongers.

Matched MeSH terms: Seasons
Fulltext Changing epidemiology of malaria in Sabah, Malaysia: increasing incidence of Plasmodium knowlesi

William T, Jelip J, Menon J, Anderios F, Mohammad R, Awang Mohammad TA, et al.

Malar J, 2014;13:390.
PMID: 25272973 DOI: 10.1186/1475-2875-13-390

While Malaysia has had great success in controlling Plasmodium falciparum and Plasmodium vivax, notifications of Plasmodium malariae and the microscopically near-identical Plasmodium knowlesi increased substantially over the past decade. However, whether this represents microscopic misdiagnosis or increased recognition of P. knowlesi has remained uncertain.

Matched MeSH terms: Seasons
Chemical characteristics of rainwater in the tropical rainforest region in northwestern Borneo

Valappil NKM, Viswanathan PM, Hamza V

Environ Sci Pollut Res Int, 2020 Jun 23.
PMID: 32572749 DOI: 10.1007/s11356-020-09542-1

A comprehensive study of the chemical composition of rainwater was carried out from October 2016 to September 2017 in the equatorial tropical rainforest region of northwestern Borneo. Monthly cumulative rainwater samples were collected from different locations in the Limbang River Basin (LRB) and were later categorized into seasonal samples representing northeast monsoon (NEM), southwest monsoon (SWM), and inter-monsoon (IM) periods. Physical parameters (pH, EC, TDS, DO, and turbidity), major ions (HCO3-, Cl-, Ca2+, Mg2+, Na+, and K+) and trace metals (Co, Ni, Cd, Fe, Mn, Pb, Zn, and Cu) were analyzed from collected rainwater samples. Rainwater is slightly alkaline with mean pH higher than 5.8. Chloride and bicarbonate are the most abundant ions, and the concentration of major ions in seasonal rainwater has shown slight variation which follows a descending order of HCO3-> Cl-> Na+ > Ca2+ > Mg2+ > K+ in NEM and Cl- > HCO3- > Na+ > Ca2+ > K+ > Mg2+ in SWM and Cl- > HCO3- > Na+ > Ca2+ > Mg2+ > K+ in IM period. Trace metals such as Fe and Ni have shown dominance in seasonal rainwater samples, and all the metals have shown variation in concentration in different seasons. Variation in chemical characteristic of seasonal rainwater samples identified through piper diagram indicates dominance of Ca2+-Mg2+-HCO3- and mixed Ca2+-Mg2+-Cl- facies during NEM, SWM, and IM periods. Statistical analysis of the results through two-way ANOVA and Pearson's correlation also indicates significant variation in physico-chemical characteristics. This suggests a variation in contributing sources during the monsoon seasons. Factor analysis confirmed the source variation by explaining the total variance of 79.80%, 90.72%, and 90.52% with three factor components in NEM, SWM, and IM rainwater samples with different loading of parameters. Enrichment factor analysis revealed a combined contribution of marine and crustal sources except K+ which was solely from crustal sources. Sample analysis of backward air mass trajectory supports all these findings by explaining seasonal variation in the source of pollutants reaching the study area. Overall, the results show that the chemical composition of seasonal rainwater samples in LRB was significantly influenced by natural as well as anthropogenic processes. These include (long-range and local) industrial activities, fossil fuel combustion, forest burning, transportation activities including road transport and shipping activities, and land-derived soil dust along with chemical constituents carried by seasonal wind.

Matched MeSH terms: Seasons
Chemical erosion of the Lilburn Cave system, Kings Canyon National Park, California

Abu-Jaber N, Hess JW, Howcroft W

Ground Water, 2001 4 5;39(2):223-9.
PMID: 11286069

Multi-year instrumental records for input, throughflow and output waters of the Lilburn Cave system provide control on denudation rates as they respond to seasonal and spatial variability. Data suggest that maximum denudation is in the late fall and early winter. This is when non-snowmelt discharge is at its maximum. At lower discharge rates the volume of water moving through the cave system is the limiting control on the volume of denudation. During periods of snowmelt the limiting control is the rate at which the calcite dissolves. This is probably the result of water flowing through wider channels during these times. Based on instrumental measurements, there is considerable variation in terms of where denudation occurs inside the cave. The loci of dissolution change from year to year. This is to be expected in the dynamic environment of the cave where materials shift routinely. This variability should be studied over longer periods of time in order to more fully understand its extent. The relatively small area of carbonate exposure relative to the area of the drainage basin gives rise to relatively high denudation rates. The carbonate is being removed at a rate of about 5000 metric tons per year, or at about 830 mm/y. This is about five times the rate reported in the humid karst regions of Malaysia. This information indicates that the relative proportion of carbonate in the drainage basin needs to be considered when trying to estimate denudation in other areas.

Matched MeSH terms: Seasons
Childhood pneumonia: a neglected, climate-sensitive disease?

Paynter S, Ware RS, Weinstein P, Williams G, Sly PD

Lancet, 2010 Nov 27;376(9755):1804-5.
PMID: 21111894 DOI: 10.1016/S0140-6736(10)62141-1
Matched MeSH terms: Seasons
Circadian and solar clocks interact in seasonal flowering

Yeang HY

Bioessays, 2009 Nov;31(11):1211-8.
PMID: 19795408 DOI: 10.1002/bies.200900078

The plant maintains a 24-h circadian cycle that controls the sequential activation of many physiological and developmental functions. There is empirical evidence suggesting that two types of circadian rhythms exist. Some plant rhythms appear to be set by the light transition at dawn, and are calibrated to circadian (zeitgeber) time, which is measured from sunrise. Other rhythms are set by both dawn and dusk, and are calibrated to solar time that is measured from mid-day. Rhythms on circadian timing shift seasonally in tandem with the timing of dawn that occurs earlier in summer and later in winter. On the other hand, rhythms set to solar time are maintained independently of the season, the timing of noon being constant year-round. Various rhythms that run in-phase and out-of-phase with one another seasonally may provide a means to time and induce seasonal events such as flowering.

Matched MeSH terms: Seasons

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