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Abstract Substance use among school students is a public health concern. Exam-related anxiety is one of the main motives for drug use. This research aimed to determine the prevalence and characteristics of psychostimulant and antidepressants use and misuse among medical and health sciences students at two large representative medical schools in West Bank Palestine. The results of a cross-sectional study, that surveyed 984 Palestinian medical and health sciences students revealed how educational experiences and newfound independence affect substance use behaviors among Palestinian medical and health sciences students. In total, 7.7% of the students reported using illicit drugs. Hallucinogens were the most commonly used drugs (2.9%), followed by central nervous system (CNS) stimulants (2.4%) and CNS depressants (1.4%), while 4.4% were using nonprescribed antidepressants, with Fluoxetine being the most used. Most drug users (72.4%) started using before they enrolled in university, and 39.5% did not realize the potential harm of these drugs. Medical students tend to use these substances less frequently than their non-medical peers. The study indicated that exam-related stress was a crucial factor in the prevalence of drug use and misuse. Peer pressure, academic, psychological, and family pressures were other primary reasons behind drug use. The study’s results indicated that the misuse of antidepressant medications and other licit and illicit substances is highly prevalent among Palestinian medical and non-medical students. The results also underscore the importance of raising awareness about drug use and providing students with accurate information about the safe use of these substances.

Odonata larvae have been intensively used as bioindicators for freshwater pollution as their community structure closely follow changes in the environment and habitat settings. In this study, 28 taxa of Odonata larvae were collected from three stations (upper, middle and lower) of a polluted river in Malaysia. The upper river basin receives effluents from an oil palm plantation. However, the middle station is presumably contaminated with anthropogenic wastes. The lower station is found to receive polluted discharges from aquaculture outlet. Several environmental parameters of water and sediment were continuously measured during the study. The water parameters showed no significant differences amongst the three stations. The species richness of Odonata was 22, 24 and 20 in the upper, middle and lower stations, respectively. The abundance of Odonata was significantly different among the studied sites. The tolerant damselfly, Pseudagrion sp. (41.22%), and facultative dragonflies, Onychothemis sp. (17.12%), were the most dominant taxa along the river stations. Onychothemis sp. and Paragomphus capricornis were equally important at the upper station [Important Species Index (ISI) 25.3 and 24.2%, respectively]. Pseudagrion sp. only scored an ISI value of 9.7%. Pseudagrion sp., P. capricornis and Onychothemis sp. were dominant in the middle station (ISI: 41.2%, 25.9% and 10.9% respectively), and Pseudagrion sp., Onychothemis sp. and Prodasineura sp. dominated the areas with dense growth of submerged aquatic weeds Hydrilla sp. in the lower station (ISI: 47.9, 24.5 and 13.8%, respectively). On the basis of the variations in larval abundance and ISI values, microhabitats differences partly in response to different types of pollutions entering the water structured the Odonata communities in this river basin.

Abstract Background Dengue is a prevalent arboviral disease and the development of insecticide resistance among its vectors impedes endeavors to control it. Coffee is drunk by millions of people daily worldwide, which is associated with the discarding of large amounts of waste. Coffee and its waste contain large amounts of chemicals many of which are highly toxic and none of which have a history of resistance in mosquitoes. Once in solution, coffee is brownish in colour, resembling leaf infusion, which is highly attractive to gravid mosquitoes. To anticipate the environmental issues related to the increasing popularity of coffee as a drink, and also to combat insecticide resistance, we explored the deterrence potentials of coffee leachates against the ovipositing and embryonic stages of the dengue vector, Aedes albopictus. Methods In a series of choice, no-choice, and embryo toxicity bioassays, we examined changes in the ovipositional behaviours and larval eclosion of Ae. albopictus in response to coffee extracts at different concentrations. Results Oviposition responses were extremely low when ovicups holding highly concentrated extract (HCE) of coffee were the only oviposition sites. Gravid females retained increased numbers of mature eggs until 5 days post-blood feeding. When provided an opportunity to oviposit in cups containing coffee extracts and with water, egg deposition occurred at lower rates in those containing coffee, and HCE cups were far less attractive to females than those containing water only. Females that successfully developed in a coffee environment preferentially oviposited in such cups when in competition with preferred oviposition sites (water cups), but this trait did not continue into the fourth generation. Larval eclosion occurred at lower rates among eggs that matured in a coffee environment, especially among those that were maintained on HCE-moistened substrates. Conclusions The observations of the present study indicate a pronounced vulnerability of Ae. albopictus to the presence of coffee in its habitats during the early phases of its life cycle. The observations that coffee repels gravid females and inhibits larval eclosion provide novel possibilities in the search for novel oviposition deterrents and anti-larval eclosion agents against dengue vectors.

BACKGROUND: The domestic dengue vector Aedes aegypti mosquitoes breed in indoor containers. However, in northern peninsular Malaysia, they show equal preference for breeding in both indoor and outdoor habitats. To evaluate the epidemiological implications of this peridomestic adaptation, we examined whether Ae. aegypti exhibits decreased survival, gonotrophic activity, and fecundity due to lack of host availability and the changing breeding behavior. METHODOLOGY/PRINCIPAL FINDINGS: This yearlong field surveillance identified Ae. aegypti breeding in outdoor containers on an enormous scale. Through a sequence of experiments incorporating outdoors and indoors adapting as well as adapted populations, we observed that indoors provided better environment for the survival of Ae. aegypti and the observed death patterns could be explained on the basis of a difference in body size. The duration of gonotrophic period was much shorter in large-bodied females. Fecundity tended to be greater in indoor acclimated females. We also found increased tendency to multiple feeding in outdoors adapted females, which were smaller in size compared to their outdoors breeding counterparts. CONCLUSION/SIGNIFICANCE: The data presented here suggest that acclimatization of Ae. aegypti to the outdoor environment may not decrease its lifespan or gonotrophic activity but rather increase breeding opportunities (increased number of discarded containers outdoors), the rate of larval development, but small body sizes at emergence. Size is likely to be correlated with disease transmission. In general, small size in Aedes females will favor increased blood-feeding frequency resulting in higher population sizes and disease occurrence.

BACKGROUND: The mosquito Ae. albopictus is usually adapted to the peri-domestic environment and typically breeds outdoors. However, we observed its larvae in most containers within homes in northern peninsular Malaysia. To anticipate the epidemiological implications of this indoor-breeding, we assessed some fitness traits affecting vectorial capacity during colonization process. Specifically, we examined whether Ae. albopictus exhibits increased survival, gonotrophic activity and fecundity due to the potential increase in blood feeding opportunities. METHODOLOGY/PRINCIPAL FINDINGS: In a series of experiments involving outdoors and indoors breeding populations, we found that Ae. albopictus lives longer in the indoor environment. We also observed increased nighttime biting activity and lifetime fecundity in indoor/domestic adapted females, although they were similar to recently colonized females in body size. CONCLUSION/SIGNIFICANCE: Taken together these data suggest that accommodation of Ae. albopictus to indoor/domestic environment may increase its lifespan, blood feeding success, nuisance and thus vectorial capacity (both in terms of increased vector-host contacts and vector population density). These changes in the breeding behavior of Ae. albopictus, a potential vector of several human pathogens including dengue viruses, require special attention.

Problem statement: Chironomidae have been recorded in rice fields throughout the world including in many countries such as India, Australia and the USA. Although some studies provide the key to genera level and note the difficulty of identifying the larvae to species level. Chironomid researches have been hindered because of difficulties in specimen preparation, identification, morphology and literature. Systematics, phylogenetics and taxonomic studies of insects developed quickly with emergence of molecular techniques. These techniques provide an effective tool toward more accurate identification of ambiguous chironomid species. Approach: Samples of chironomids larvae were collected from rice plots at Bukit Merah Agricultural Experimental Station (BMAES), Penang, Malaysia. A 710 bp fragment of mitochondrial gene Cytochrome Oxidase subunit I (COI) was amplified and sequenced. Results: Five species of Chironomidae; three species of subfamily Chironominae, Chironomus kiiensis, Polypedilum trigonus, Tanytarsus formosanus, two species of subfamily Tanypodinae, Clinotanypus sp and Tanypus punctipennis were morphologically identified. The phylogenetic relationship among these species was been investigated. High sequence divergence was observed between two individuals of the presumed C. kiiensis and it is suggested that more than one species may be present. However the intraspecific sequence divergence was lower between the other species of Tanypodinae subfamily. Interestingly, Tanytarsus formosanus showed close phylogenetic relationship to Tanypodinae species and this presumably reflect co-evolutionary traits of different subfamilies. Conclusion: The sequence of the mtDNA cytochrome oxidase subunit I gene has proven useful to investigate the phylogenetic relationship among the ambiguous species of chironomids. Key words: Chironomidae, DNA sequencing, cytochrome oxidase subunit I, INTRODUCTION Chironomidae is considered a species-rich family of flies, with almost 15000 species described worldwide (1). Generally, Chironomidae larvae are inhabitants of organically enriched places such as in flowing water [...]

This study is based on bird surveys conducted on Pulau Rawa, Johor, Malaysia from December 2016 till October 2017. Line transect surveys were conducted twice in each month and attempts were made to cover all habitats of the island. A total of 26 bird species were recorded from 19 families. The Shannon-Weiner species diversity index (H) was 2.12 for abundance and 0.264 for evenness. Margalef species richness index was 2.99. The density of birds on the island were estimated using distance sampling. The highest density of birds on the island was recorded in the month of May with 559.05 individuals per ha and the lowest was in the month of January with a density of 63.65 individuals per ha. The average density of birds during the monsoon season was 133.78 and 288.95 individuals per ha during the dry season; these provided an indication that the monsoon weather significantly affected the density of birds found on the tropical island. This study aims to provide further information on bird population status on islands, as well as future assessment into impacts of ongoing human development unfolding in Pulau Rawa and other islands. [ABSTRACT FROM AUTHOR]

This study investigated the diet of introduced barn owls (Tyto alba javanica , Gmelin) in the urban area of the Main Campus of Universiti Sains Malaysia, Penang, Malaysia, based on collected regurgitated pellets. We also compared the diet of the introduced barn owls with the diet of barn owls from two agricultural areas, i.e. oil palm plantations and rice fields. Pellet analysis of introduced barn owls showed that commensal Norway rats, Rattus norvegicus , made up the highest proportion of the diet (65.37% prey biomass) while common shrews, Suncus murinus were the second highest consumed prey (30.12% prey biomass). Common plantain squirrel, Callosciurus notatus , made up 4.45% of the diet while insects were taken in a relatively small amount (0.046% prey biomass). Introduced barn owls showed a preference for medium-sized prey, i.e. 40–120 g (52.96% biomass and 38.71% total). In agricultural areas, rice field rats, Rattus argentiventer predominated the diet of barn owls (98.24% prey biomass) in rice fields while Malayan wood rats, Rattus tiomanicus , were the most consumed prey in oil palm plantations (99.5% prey biomass). Food niche breadth value was highest for barn owls introduced in an urban area with a value of 2.90, and 1.06 in rice fields and 1.22 in oil palm plantations. Our analysis reiterates the prey preference of barn owls in various landscapes for small mammals. Our results also indicate the suitability of utilizing barn owls as a biological control not only in agricultural areas, but also as a biological control agent for commensal rodent pests in urban areas. [ABSTRACT FROM AUTHOR]

Weaver ant (Oecophylla smaragdina) is an important insect community in tree canopies, but little is known about their foraging behaviours. Therefore, a field experiment was conducted in order to assess the food preferences and foraging activity of weaver ants for three consecutive days. The food preferences of the weaver ants were evaluated using three types of foods (tuna, chicken skin, and milk powder) containing varying contents of protein, lipid, and carbohydrate. The foraging activity was examined based on two parameters, namely temperature and relative humidity which were recorded throughout the study. Results revealed that food higher in protein content was highly preferred by the O. smaragdina compared to foods with lipid and carbohydrate contents, and the foraging activity of the O. smaragdina was significantly influenced by both temperature and relative humidity. The present study exhibits how the weaver ants respond to different types of foods and indirectly, forming a strategic foraging activity to maximise their food supplies for their colony. [ABSTRACT FROM AUTHOR]

This study was conducted to isolate and identify lactobacilli from larval and adult midgut of wild Aedes aegypti (Ae. aegypti) to find candidate bacteria for paratransgenic control. Characterization of the bacterial symbionts was done using Gram staining, motility test, catalase test, and biochemical tests, among others, and the morphological features were confirmed using a standard scheme that simplifies the identification of lactic acid bacteria. A total of 174 strains were isolated and identified, 135 strains from larval midgut and 39 strains from adult midgut (mean ± SE, 4.00 ± 0.72; P = 0.00). The isolated species were confirmed to be Lactobacillus fermentum, L. casei, L. acidophilus, L. viridescens, L. brevis and L. gasseri. It can be concluded that Ae. aegypti has the potential of harboring the cultivable bacterial symbionts. In conclusion, the isolated species were nominated for paratransgenic control, particularly L. fermentum, being found in large numbers from both larval and adulxt midgut. [ABSTRACT FROM AUTHOR]

Copyright of Slovak Raptor Journal is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Entomotoxicology is a field associated with the detection of drugs and toxins in arthropods that feed on a corpse and the effects of these agents on their physiology and growth. This field has broad applications in forensic investigations related to estimating the time of death or post-mortem interval (PMI). Heroin has a place of interest in toxicology as it is frequently associated with death by abuse or suicide. The effects of heroin on the blowfly, Lucilia cuprina (Weidemann) growth and development have yet to be investigated in depth. Our study was conducted to determine the effects of different heroin concentrations on the developmental growth rate, and duration of the life cycle of Lucilia cuprina reared on minced buffalo meat. Five different concentration of heroin were prepared and were fed on to Lucilia cuprina larvae, and their length and duration of their life stage were determined. This study found that an increase in heroin concentrations (0.5-10 µg/µL) mixed in minced buffalo meat sped up the rate of larval growth and its developmental cycle. Thus, the supplementation of heroin shortened the life cycle of Lucilia cuprina. The reduction in Lucilia cuprina life cycle duration due to heroin can potentially lead to a miscalculation of the PMI estimation in forensic examination. Hence, consideration should be allowed for such an effect where heroin is present in the body in an autopsy. It is worthwhile examining if heroin has a similar effect in other carrion-feeding insect species. [ABSTRACT FROM AUTHOR]

This study aims to fully integrated and validated spatial temporal statistical model using epidemiological data as a predictive model for surveillance and control of DF cases. Kernel-density estimation (KDE) method was carried out by using spatial union analysis in order to predict and visualize the DF hotspot area by monthly basis in the Subang Jaya area. The generated maps were then verified using Receiver operating characteristics (ROC) was performed to validate the DF hotspot simulation model. Spatial analysis showed that the dengue epidemics in Subang Jaya were spatially dependent. This analysis demonstrated spatial clustering of dengue activity which can facilitate prediction of the magnitude, timing and location of future dengue epidemic. The model developed highlights the adaptation capabilities of the approach where the accuracy assessment result showed accuracy about 60% agreements between the hotspot map and the actual DF location data. It can thus be suggested that any future population increase will be associated with increased DF risk in areas which already accommodate this disease environmentally, climatically and socioeconomically. Future risk could be modelled using the same methods. This would help decision maker in choosing which areas should be under intensive treatment to counter mosquito breeding and reduce prevalence of DF. [ABSTRACT FROM AUTHOR]

This study was performed to establish the genetic variability of Aedes albopictus within Subang Jaya, Selangor, Malaysia, by using the nicotinamide adenine dinucleotide dehydrogenase 5 subunit ( ND5) mitochondrial DNA (mtDNA) marker. A total of 90 samples were collected from 9 localities within an area of the Subang Jaya Municipality. Genetic variability was determined through the amplification and sequencing of a fragment of the ND5 gene. Eight distinct mtDNA haplotypes were identified. The evolutionary relationship of the local haplotypes alongside 28 reference strains was used to construct a phylogram, the analysis of which revealed low genetic differentiation in terms of both nucleotide and haplotype diversity. Bayesian method was used to infer the phylogenetic tree, revealing a unique relationship between local isolates. The study corroborates the reliability of ND5 to identify distinct lineages for polymorphism-based studies and supplements the existing body of knowledge regarding its genetic diversity. This in turn could potentially aid existing vector control strategies to help mitigate the risk and spread of the dengue virus. [ABSTRACT FROM AUTHOR]

Effects of variations in stream environmental conditions on a nymphal ephemeropteran community were investigated in twoforested catchments in Peninsular Malaysia; Gunung Jerai (GJ) and Royal Belum State Park (RBSP). Ephemeropteran nymphs were collected monthly from both catchments using an aquatic net over a period of a year (2008- 2009). Ecological indices were calculated to compare community features and diversity of the ephemeropterans in the two catchments. Ephemeropteran taxa interactions with environmental parameters and their community structures were investigated using multivariate analysis (detrended canonical analysis and canonical correspondence analysis) and Bray Curtis similarity measure, respectively. From the two catchments, 22 ephemeropteran taxa were recorded and taxonomic richness was higher in undisturbed RBSP (20 taxa) than in slightly impacted GJ (12 taxa) streams. Environmental parameters were more important than geographical location in separating ephemeropteran communities in both catchments but similarities among communities in streams in the same catchment were detectable. Water temperature and pH were strong descriptors of ephemeropteran community structure in GJ. High water temperature was favourable to Isonychia sp., Crinitella sp., Habrophlebiodes sp. and Tricorythus sp. In RBSP, pH, water velocity, and canopy cover were important in shaping ephemeropteran communities. Heptagenia sp., Campsoneuria sp., and Habrophlebiodes sp. were negatively associated with elevating pH and fast running water. This study provides useful information for preservations of suitable habitats for the ephemeropterans in undisturbed and potentially disturbed forest streams in Malaysia. [ABSTRACT FROM AUTHOR]

Background: Dengue fever (DF) is an urban vector-borne disease transmitted by Aedes aegypti and Aedes albopictus. Both species deposit their eggs in favorable breeding sites either in natural or artificial containers. An understanding of their habitat characteristics is crucial in curbing DF outbreaks. Methods: A search and destroy survey was carried out at 10 dengue hotspot localities in Shah Alam, Malaysia. A quantitative in-situ measurement of selected physical parameters was conducted focusing on the environmental characteristics and the presence of vegetation. Larvae and pupae found in different types of container were morphologically identified. Results: Evidence of breeding was discovered in 62 containers. Rubber materials (container efficiency: 2.10), with clear water in the presence of dead vegetation (71 and 33% respectively) were found to be most efficient for pupae development. Furthermore, low water volume (60%) was preferred for breeding purposes. Kruskal- Wallis test demonstrated that water volume, wind velocity and distance from habitation were statistically significant towards dengue vectors. Conclusions: Our findings have provided the profile of Aedes species based on environmental and water conditions in hotspot areas in Malaysia. These outcomes provide useful information regarding container characteristics that can enable selective elimination of vector habitat thus minimizing the risk of dengue outbreak. [ABSTRACT FROM AUTHOR]

The life table developmental attributes of laboratory colonies of wild strains of Aedes albopictus and Aedes aegypti were analyzed and compared based on the age-stage, two-sex life table. Findings inclusive in this study are: adult preoviposition periods, total preoviposition period, mean intrinsic rate of increase ( r), mean finite rate of increase ( λ), net reproductive rates ( R0), and mean generation time ( T). The total preadult development time was 9.47 days for Ae. albopictus and 8.76 days for Ae. aegypti. The life expectancy was 19.01 days for Ae. albopictus and 19.94 days for Ae. aegypti. Mortality occurred mostly during the adult stage. The mean development time for each stage insignificantly correlated with temperature for Ae. albopictus ( r = −0.208, P > 0.05) and ( r = −0.312, P > 0.05) for Ae. aegypti. The population parameters suggest that Ae. albopictus and Ae. aegypti populations are r-strategists characterized by a high r, a large R0, and short T. This present study provides the first report to compare the life parameters of Ae. albopictus and Ae. aegypti strains from Penang island, Malaysia. [ABSTRACT FROM AUTHOR]

The life history and the influence of environmental parameters on Thalerosphyrus were investigated in two first-order rivers-the Batu Hampar River and the Teroi River of Gunung Jerai, Kedah-in northern peninsular Malaysia. Based on nymphal body length, Thalerosphyrus was found to be trivoltine in both rivers, regardless of the altitudinal difference, but its population abundance was four times higher in the Teroi River, presumably related to its better survival in the lower water temperature. At least nine instars of Thalerosphyrus were detected in the field-collected nymphs. Its life cycle was completed within 2.5-3.0 months, with overlapping cohorts and continual emergence of up to 3 months. The main driving factors of the high abundance of Thalerosphyrus were the water temperature and habitat quality. [ABSTRACT FROM AUTHOR]

A study was conducted to establish polymorphic variation of the mitochondrial DNA encoding the cytochrome oxidase subunit 1 (CO1) gene in Aedes albopictus isolated from 2 hot spot dengue-infested areas in the Subang Jaya District, Malaysia. A phylogenetic analysis was performed with the use of sequences obtained from USJ6 and Taman Subang Mas (TSM). Comparison of the local CO1 sequences with a laboratory strain (USM), alongside reference strains derived from the GenBank database revealed low genetic variation in terms of nucleotide differences and haplotype diversity. Four methods were used to construct a phylogenetic tree and illustrate the genetic relationship of the 37 Ae. albopictus populations based on the CO1 sequences, namely neighbor-joining (NJ), maximum parsimony (MP), maximum likelihood (ML), and Bayesian method, which revealed a distinct relationship between isolates from USJ6 and TSM. Our findings provide new information regarding the genetic diversity among morphologically similar Ae. albopictus, which has not been reported to date. [ABSTRACT FROM AUTHOR]

The effectiveness of the synthetic insecticides trichlorfon, lambda-cyhalothrin, cypermethrin emulsion concentrated (EC) and cypermethrin emulsion water based (EW) and a bio-insecticide, Bacillus thuringiensis subsp. kurstaki (Btk), was evaluated at 3, 7, 14 and 30 days after treatment (DAT) for the control of Metisa plana larvae in an oil palm (Elaeis guineensis) plantation in Malaysia. Although all synthetic insecticides effectively reduced the larval population of M. plana, trichlorfon, lambda-cyhalothrin and cypermethrin EC were the fastest-acting. The larval population dropped below the economic threshold level (ETL) 30 days after a single application of the synthetic insecticides. Application of Btk, however, gave poor results, with the larval population remaining above the ETL post treatment. In terms of operational productivity, ground spraying using power spray equipment was time-consuming and resulted in poor coverage. Power spraying may not be appropriate for controlling M. plana infestations in large fields. Using a power sprayer, one man could cover 2-3 ha per day. Hence, power spraying is recommended during outbreaks of infestation in areas smaller than 50 ha. [ABSTRACT FROM AUTHOR]

Copyright of Slovak Raptor Journal is the property of Sciendo and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)