Biomass accumulation in a naturally regenerating lowland secondary forest and an Acacia mangium stand in Sarawak

The floristic composition and the above ground biomass of a naturally regenerating area and a three-and-a-half year-old Acacia mangium stand are compared. The naturally regenerating area averages 1.5 m in height; generally has more variety of plants and is dominated by Imperata cylindrica, Dicranopteris linearis, Pteridium sp. and Scleria sp. whereas the A. mangium stand has a top height of 15.5 m and fewer genera of plants (including cocoa). I. cylindrica and D. linearis were also found in the A. mangium stand but grew less vigorously in isolated patches. There was 6.2 t/ha of live organic matter in the naturally regenerating area and approximately 59.0 t/ha in the A. mangium stand

Rainfall interception, throughfall and stemflow in a secondary forest

The presence of forest or any other vegetative cover over an area of land influences the distribution pattern of rainfall. Some of the rain is intercepted and retained by the leaves and other parts of the trees and eventually lost to the atmosphere in the form of evaporation. The rain water that reaches the soil surface will arrive there by throughfall (passes directly through open spaces not covered by foliage or as drips from the vegetative parts of the tree) and also by stemflow (flows down the surface of the stem). Measurements of the amount of interception, throughfall and stemflow are therefore necessary towards understanding the role of a forest cover in the hydrological cycle in a forest ecosystem. Studies of rain interception, throughfall and stemflow have received little attention in Malaysia. Kenworthy (1970) reported one such study under primary and disturbed forests at Ulu Gombak Reserve. Teoh(1971) conducted a similar study in a rubber plantation at Sungei Buloh and Low (1972) reported the work done at Sungai Lui catchment area. This paper describes the results obtained from an investigation conducted at the Air Hitam Forest Reserve, Puchong, Selangor to find out the percent interception, throughfall and stemflow. The vegetation is typically a secondary lowland dipterocarp forest of the"Kedondong Kempas" type. An attempt was also made to relate crown area and diameter of trees at breast height (D.B.H.) to stemflow

Pengaruh Amalan Jenaka Terhadap Pengajaran Dan Pembelajaran Murid (The Influence Of Humour In Teaching And Learning)

Tujuan kajian ini dijalankan ialah untuk melihat peranan amalan jenaka atau kecindan dalam kalangan guru pelatih dan pandangan murid terhadap amalan jenaka guru serta kesannya terhadap pembelajaran. Selain daripada itu, kajian ini juga adalah untuk melihat sama ada amalan tersebut dilakukan oleh guru pelatih semasa sesi pengajaran dan pembelajaran di bilik darjah. Di samping itu, kajian ini akan mengenal pasti sama ada amalan jenaka guru pelatih dapat mewujudkan keseronokan untuk belajar dalam kalangan murid serta intensiti atau tahap jenaka yang dilaksanakan oleh guru pelatih semasa mengajar. Kajian kuantitatif ini menggunakan kaedah kajian tinjauan bagi melihat pandangan guru pelatih dan murid sekolah terhadap amalan jenaka dalam pendidikan. Kajian ini adalah merupakan kajian rintis kepada kajian sebenar yang akan dilaksanakan kepada sekumpulan guru pelatih lain yang terdedah kepada latihan mengajar di sekolah. Murid tingkatan tiga daripada sebuah kelas di sebuah sekolah menengah di Cheras, Selangor dan guru pelatih daripada sebuah institusi pengajian awam di Kuala Lumpur yang sedang menjalani perguruan dalam semester kedua telah dipilih sebagai sampel kajian. Instrumen kajian terdiri daripada dua set soal selidik iaitu soal selidik murid dan soal selidik guru pelatih. Hasil kajian ini menunjukkan amalan jenaka guru boleh meningkatkan interaksi sesama rakan sejawat guru dan sesama rakan murid. Suasana pembelajaran yang seronok dapat diwujudkan sekiranya guru berjenaka dalam bilik darjah semasa pengajaran dan pembelajaran. Guru pelatih telah mengamalkan jenaka semasa sesi pengajaran dan pembelajaran. Mereka juga menganggap amalan ini boleh mewujudkan kesan yang positif terhadap pengajaran dan pembelajaran murid. Sementara tahap jenaka yang dilakukan oleh guru pelatih adalah dengan kadar yang sederhana iaitu antara tiga hingga empat kali bagi setiap sesi pengajaran. Kekerapan ini juga dianggap sebagai jumlah yang sesuai bagi seseorang guru melakukannya

The impact of fluid balances in the first 48 hours on mortality in the critically ill patients

Introduction: There has been increasing evidence of detrimental effects of cumulative positive fluid balance in critically ill patients. The postulated mechanism of harm is the development of interstitial oedema, with resultant increase morbidity and mortality. We aim to assess the impact of positive fluid balance within the first 48 hours on mortality in our local ICU population. Methods: This was a secondary analysis of a single centre, prospective observational study. All ICU patients more than 18 years were screened for inclusion in the study. Admission of less than 48 hours, post-elective surgery and ICU readmission were excluded. Cumulative fluid balance either as volume or percentage of body weight from admission was calculated over 6, 24 and 48 hour period from ICU admission. Results: A total of 143 patients were recruited, of these 33 died. There were higher cumulative fluid balances at 6, 24 and 48 hours in non- survivors compared to survivors. However, after adjusted for severity of illness, APACHE II Score, they were not predictive of mortality. Sensitivity analysis on sub-cohort of patients with acute kidney injury (AKI) showed only an actual 48-hour cumulative fluid balance was independently predictive of mortality (1.21 (1.03 to 1.42)). Conclusions: Cumulative fluid balance was not independently predictive of mortality in a heterogenous group of critically ill patients. However, in subcohort of patients with AKI, a 48-hour cumulative fluid balance was independently predictive of mortality. An additional tile is thus added to the mosaic of findings on the impact of fluid balance in a hetergenous group of critically ill patients, and in sub- cohort of AKI patients

Pengaruh amalan jenaka terhadap pengajaran dan pembelajaran murid

Tujuan kajian ini dijalankan ialah untuk melihat peranan amalan jenaka atau kecindan dalam kalangan guru pelatih dan pandangan murid terhadap amalan jenaka guru serta kesannya terhadap pembelajaran. Selain daripada itu, kajian ini juga adalah untuk melihat sama ada amalan tersebut dilakukan oleh guru pelatih semasa sesi pengajaran dan pembelajaran di bilik darjah. Di samping itu, kajian ini akan mengenal pasti sama ada amalan jenaka guru pelatih dapat mewujudkan keseronokan untuk belajar dalam kalangan murid serta intensiti atau tahap jenaka yang dilaksanakan oleh guru pelatih semasa mengajar. Kajian kuantitatif ini menggunakan kaedah kajian tinjauan bagi melihat pandangan guru pelatih dan murid sekolah terhadap amalan jenaka dalam pendidikan. Kajian ini adalah merupakan kajian rintis kepada kajian sebenar yang akan dilaksanakan kepada sekumpulan guru pelatih lain yang terdedah kepada latihan mengajar di sekolah. Murid tingkatan tiga daripada sebuah kelas di sebuah sekolah menengah di Cheras, Selangor dan guru pelatih daripada sebuah institusi pengajian awam di Kuala Lumpur yang sedang menjalani perguruan dalam semester kedua telah dipilih sebagai sampel kajian. Instrumen kajian terdiri daripada dua set soal selidik iaitu soal selidik murid dan soal selidik guru pelatih. Hasil kajian ini menunjukkan amalan jenaka guru boleh meningkatkan interaksi sesama rakan sejawat guru dan sesama rakan murid. Suasana pembelajaran yang seronok dapat diwujudkan sekiranya guru berjenaka dalam bilik darjah semasa pengajaran dan pembelajaran. Guru pelatih telah mengamalkan jenaka semasa sesi pengajaran dan pembelajaran. Mereka juga menganggap amalan ini boleh mewujudkan kesan yang positif terhadap pengajaran dan pembelajaran murid. Sementara tahap jenaka yang dilakukan oleh guru pelatih adalah dengan kadar yang sederhana iaitu antara tiga hingga empat kali bagi setiap sesi pengajaran. Kekerapan ini juga dianggap sebagai jumlah yang sesuai bagi seseorang guru melakukannya

Do tropical forest leaves suffer more insect herbivory? A comparison of tropical versus temperate herbivory, estimated from leaf litter

It is generally believed that tropical forests suffer more herbivory, as a proportion of leaf area, than do temperate forests. Reviews so far have compared studies performed by different authors using very different methodologies. Here we carried out studies on 125 samples at 86 localities in eastern North America and on 75 samples taken at five localities in Malaysia and Singapore, including both mature secondary and primary forest. Samples in North America were spread over 3 years. In tropical Asia, the samples were taken at four time slices at least 8 months apart, scattered over a 4-year period. Total herbivore damage during the lifetime of tree leaves was estimated from the percentage area damaged in recently fallen, undecayed leaves from the forest floor, using scanner-linked software. In terms of percentage damage per leaf, the results suggest that lowland tropical forest has significantly higher leaf herbivory (5.82%) than temperate forest (5.48%). This is in accord with the general expectation that aseasonal tropical forests should have more herbivory damage. However, when percentage damage ‘per unit time of growing season’ is calculated based on an estimate of leaf lifetime in the tropics, tropical lowland herbivory damage turns out to be a fraction (about one half) of that in the temperate zone. Thus, these results tend to put in question the widely held view that herbivore damage is markedly more intense in the tropics. Over total leaf lifetime, the intensity of damage in the tropical area is only slightly higher than temperate regions. In terms of intensity of herbivory on leaves per unit of time, the opposite seems to be the case. It is uncertain which index should be taken as more significant in interpreting the selection pressure for anti-herbivore defenses in the tropics

Removal of Arsenic, Boron, and Selenium from Excavated Rocks by Consecutive Washing

This paper describes the leaching behavior and release mechanisms of arsenic (As), boron (B) and selenium (Se) from excavated rocks using sequential extraction for solid-phase fractionation, batch experiments with pH variation, and consecutive batch experiments with changes in the solid-liquid mixing ratios. Arsenic in the excavated rock was mostly found with the sulfides/organic matter fraction while majority of the leachable B and Se were associated with the exchangeable phases. The leaching of As was strongly pH dependent, Se was pH dependent only around the acidic region, and B was pH independent. Consecutive washing technique with deionized water effectively lowered the B and Se concentrations in the leachate below the drinking water standards of Japan, but was inefficient in the removal of As. Arsenic exhibited non-conservative leaching behavior and its movement was affected by processes like dissolution, precipitation and pyrite oxidation. In contrast, B and Se behaved more conservatively, resulting in their easy removal from the excavated rock by simple washing and dilution