Publications by authors named "Feroz S"

46 Publications

Exploring the interaction between the antiallergic drug, tranilast and human serum albumin: Insights from calorimetric, spectroscopic and modeling studies.

Int J Pharm 2015 Aug 30;491(1-2):352-8. Epub 2015 Jun 30.

Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.

The interaction of tranilast (TRN), an antiallergic drug with the main drug transporter in human circulation, human serum albumin (HSA) was studied using isothermal titration calorimetry (ITC), fluorescence spectroscopy and in silico docking methods. ITC data revealed the binding constant and stoichiometry of binding as (3.21 ± 0.23) × 10(6)M(-1) and 0.80 ± 0.08, respectively, at 25°C. The values of the standard enthalpy change (ΔH°) and the standard entropy change (ΔS°) for the interaction were found as -25.2 ± 5.1 kJ mol(-1) and 46.9 ± 5.4 J mol(-1)K(-1), respectively. Both thermodynamic data and modeling results suggested the involvement of hydrogen bonding, hydrophobic and van der Waals forces in the complex formation. Three-dimensional fluorescence data of TRN-HSA complex demonstrated significant changes in the microenvironment around the protein fluorophores upon drug binding. Competitive drug displacement results as well as modeling data concluded the preferred binding site of TRN as Sudlow's site I on HSA.
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http://dx.doi.org/10.1016/j.ijpharm.2015.06.042DOI Listing
August 2015

Supramolecular interaction of 6-shogaol, a therapeutic agent of Zingiber officinale with human serum albumin as elucidated by spectroscopic, calorimetric and molecular docking methods.

Phytomedicine 2015 Jun 9;22(6):621-30. Epub 2015 Apr 9.

Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia; Centre of Research for Computational Sciences and Informatics for Biology, Bioindustry, Environment, Agriculture and Healthcare (CRYSTAL), Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia. Electronic address:

Background: 6-Shogaol, one of the main bioactive constituents of Zingiber officinale has been shown to possess various therapeutic properties. Interaction of a therapeutic compound with plasma proteins greatly affects its pharmacokinetic and pharmacodynamic properties.

Purpose: The present investigation was undertaken to characterize the interaction between 6-shogaol and the main in vivo transporter, human serum albumin (HSA).

Methods: Various binding characteristics of 6-shogaol-HSA interaction were studied using fluorescence spectroscopy. Thermal stability of 6-shogaol-HSA system was determined by circular dichroism (CD) and differential scanning calorimetric (DSC) techniques. Identification of the 6-shogaol binding site on HSA was made by competitive drug displacement and molecular docking experiments.

Results: Fluorescence quench titration results revealed the association constant, Ka of 6-shogaol-HSA interaction as 6.29 ± 0.33 × 10(4) M(-1) at 25 ºC. Values of the enthalpy change (-11.76 kJ mol(-1)) and the entropy change (52.52 J mol(-1) K(-1)), obtained for the binding reaction suggested involvement of hydrophobic and van der Waals forces along with hydrogen bonds in the complex formation. Higher thermal stability of HSA was noticed in the presence of 6-shogaol, as revealed by DSC and thermal denaturation profiles. Competitive ligand displacement experiments along with molecular docking results suggested the binding preference of 6-shogaol for Sudlow's site I of HSA.

Conclusion: All these results suggest that 6-shogaol binds to Sudlow's site I of HSA through moderate binding affinity and involves hydrophobic and van der Waals forces along with hydrogen bonds.
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http://dx.doi.org/10.1016/j.phymed.2015.03.016DOI Listing
June 2015

Spectrofluorometric and molecular docking studies on the binding of curcumenol and curcumenone to human serum albumin.

Int J Mol Sci 2015 Mar 6;16(3):5180-93. Epub 2015 Mar 6.

Department of Chemistry, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.

Curcumenol and curcumenone are two major constituents of the plants of medicinally important genus of Curcuma, and often govern the pharmacological effect of these plant extracts. These two compounds, isolated from C. zedoaria rhizomes were studied for their binding to human serum albumin (HSA) using the fluorescence quench titration method. Molecular docking was also performed to get a more detailed insight into their interaction with HSA at the binding site. Additions of these sesquiterpenes to HSA produced significant fluorescence quenching and blue shifts in the emission spectra of HSA. Analysis of the fluorescence data pointed toward moderate binding affinity between the ligands and HSA, with curcumenone showing a relatively higher binding constant (2.46 × 105 M-1) in comparison to curcumenol (1.97 × 104 M-1). Cluster analyses revealed that site I is the preferred binding site for both molecules with a minimum binding energy of -6.77 kcal·mol-1. However, binding of these two molecules to site II cannot be ruled out as the binding energies were found to be -5.72 and -5.74 kcal·mol-1 for curcumenol and curcumenone, respectively. The interactions of both ligands with HSA involved hydrophobic interactions as well as hydrogen bonding.
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http://dx.doi.org/10.3390/ijms16035180DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4394470PMC
March 2015

A comparative analysis on the binding characteristics of various mammalian albumins towards a multitherapeutic agent, pinostrobin.

Exp Anim 2015 16;64(2):101-8. Epub 2014 Dec 16.

Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, 50603 Kuala Lumpur, Malaysia.

The interaction of pinostrobin (PS), a multitherapeutic agent with serum albumins of various mammalian species namely, goat, bovine, human, porcine, rabbit, sheep and dog was investigated using fluorescence quench titration and competitive drug displacement experiments. Analysis of the intrinsic fluorescence quenching data revealed values of the association constant, K(a) in the range of 1.49 - 6.12 × 10(4) M(-1), with 1:1 binding stoichiometry. Based on the PS-albumin binding characteristics, these albumins were grouped into two classes. Ligand displacement studies using warfarin as the site I marker ligand correlated well with the binding data. Albumins from goat and bovine were found to be closely similar to human albumin on the basis of PS binding characteristics.
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http://dx.doi.org/10.1538/expanim.14-0053DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4427724PMC
February 2016

Probing the interaction of a therapeutic flavonoid, pinostrobin with human serum albumin: multiple spectroscopic and molecular modeling investigations.

PLoS One 2013 8;8(10):e76067. Epub 2013 Oct 8.

Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, Kuala Lumpur, Malaysia.

Interaction of a pharmacologically important flavonoid, pinostrobin (PS) with the major transport protein of human blood circulation, human serum albumin (HSA) has been examined using a multitude of spectroscopic techniques and molecular docking studies. Analysis of the fluorescence quenching data showed a moderate binding affinity (1.03 × 10(5) M(-1) at 25°C) between PS and HSA with a 1∶1 stoichiometry. Thermodynamic analysis of the binding data (ΔS = +44.06 J mol(-1) K(-1) and ΔH = -15.48 kJ mol(-1)) and molecular simulation results suggested the involvement of hydrophobic and van der Waals forces, as well as hydrogen bonding in the complex formation. Both secondary and tertiary structural perturbations in HSA were observed upon PS binding, as revealed by intrinsic, synchronous, and three-dimensional fluorescence results. Far-UV circular dichroism data revealed increased thermal stability of the protein upon complexation with PS. Competitive drug displacement results suggested the binding site of PS on HSA as Sudlow's site I, located at subdomain IIA, and was well supported by the molecular modelling data.
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http://journals.plos.org/plosone/article?id=10.1371/journal.pone.0076067PLOS
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3792979PMC
June 2014

Evaluation and comparison of dimensional accuracy of newly introduced elastomeric impression material using 3D laser scanners: an in vitro study.

J Contemp Dent Pract 2013 Mar 1;14(2):265-8. Epub 2013 Mar 1.

Department of Prosthodontics, Saraswati-Dhanwantari Dental College, Parbhani, Maharashtra, India.

Aim: Aim of the present study was to comparatively evaluate dimensional accuracy of newely introduced elastomeric impression material after repeated pours at different time intervals.

Materials And Methods: In the present study a total of 20 (10 + 10) impressions of master model were made from vinyl polyether silicone and vinyl polysiloxane impression material. Each impression was repeatedly poured at 1, 24 hours and 14 days. Therefore, a total of 60 casts were obtained. Casts obtained were scanned with three-dimensional (3D) laser scanner and measurements were done.

Results: Vinyl polyether silicone produced overall undersized dies, with greatest change being 0.14% only after 14 days. Vinyl polysiloxane produced smaller dies after 1 and 24 hours and larger dies after 14 days, differing from master model by only 0.07% for the smallest die and to 0.02% for the largest die.

Conclusion: All the deviations measured from the master model with both the impression materials were within a clinically acceptable range.

Clinical Significance: In a typical fixed prosthodontic treatment accuracy of prosthesis is critical as it determines the success, failure and the prognosis of treatment including abutments. This is mainly dependent upon fit of prosthesis which in turn is dependent on dimensional accuracy of dies, poured from elastomeric impressions.
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http://dx.doi.org/10.5005/jp-journals-10024-1311DOI Listing
March 2013

A comparative evaluation of flexural strength of commercially available acrylic and modified polymethylmethacrylate: an in vitro study.

J Contemp Dent Pract 2013 Jan 1;14(1):80-3. Epub 2013 Jan 1.

Department of Prosthodontics, People's Dental Academy, Bhopal, Madhya Pradesh, India.

Aim: The purpose of this study was to evaluate and compare the flexural strength of commercially available acrylic (trevalone) and modified polymethylmethacrylate (PMMA).

Materials And Methods: Four groups were tested; Group 1- control group regular MMA, group 2-2% methacrylic acid, 88% MMA, group 3-16% methacrylic acid, 84% MMA group 4- 20% methacrylic acid, 80% MMA 15 resin specimens of each group were polymerized. After processing, the specimens were subjected for flexural strength testing using three point bending test in a Universal Testing Machine. All data was statistically analyzed with one-way ANOVA, differences within the groups were analyzed by Scheffe's analysis.

Results: As the ratio of incorporated methacrylic acid to PMMA increased, the flexural strength decreased. Analysis of data revealed a significant decrease in flexural strength of specimens (p < 0.000) after incorporation of 12%, 16%, 20% methacrylic acid to heat polymerized acrylic resin, when compared with the control group. Lowest flexural strength was observed with specimens containing 20% methacrylic acid and highest flexural strength was observed with specimens containing conventional monomer without methacrylic acid.

Conclusion: It was observed that as the concentration of methacrylic acid in heat polymerized acrylic resin increases, the flexural strength decreases. Lowest flexural strength was observed with specimens containing 20% methacrylic acid and highest flexural strength was observed with specimens containing conventional monomer without methacrylic acid.

Clinical Significance: The major advantages of addition of methacrylic acid to polymethylmethacrylate could be for the elderly people with restricted manual dexterity or cognitive disturbances, especially for patients who do not follow an adequate denture cleansing protocol and diabetic patients who are more susceptible for denture stomatitis.
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http://dx.doi.org/10.5005/jp-journals-10024-1275DOI Listing
January 2013

Does recovery in the spectral characteristics of GdnHCl-denatured Bacillus licheniformis α-amylase due to added calcium point towards protein stabilization?

Biosci Biotechnol Biochem 2013 7;77(1):87-96. Epub 2013 Jan 7.

Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya, Muala Lumpur, Malaysia.

Treatment of Bacillus licheniformis α-amylase (BLA) with guanidine hydrochloride (GdnHCl) produced both denatured and aggregated forms of the enzyme as studied by circular dichroism, fluorescence, UV difference spectroscopy, size exclusion chromatography (SEC), and enzymatic activity. The presence of CaCl(2) in the incubation mixture produced significant recovery in spectral signals, being complete in presence of 10 mM CaCl(2), as well as in enzymatic activity, which is indicative of protein stabilization. However, the SEC results obtained with GdnHCl-denatured BLA both in the absence and the presence of 10 mM CaCl(2) suggested significant aggregation of the protein in the absence of CaCl(2) and disaggregation in its presence. Although partial structural stabilization with significant retention of enzymatic activity was observed in the presence of calcium, it was far from the native state, as reflected by spectral probes. Hence, spectral results as to BLA stabilization should be treated with caution in the presence of aggregation.
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http://dx.doi.org/10.1271/bbb.120592DOI Listing
July 2013

Personal disaster preparedness: an integrative review of the literature.

Disaster Med Public Health Prep 2012 Oct;6(3):217-31

Johns Hopkins Bloomberg School of PublicHealth, Public Health Preparedness Programs, 615 N Wolfe St, Baltimore, MD 21205, USA.

Experts generally agree that individuals will require partial or complete self-sufficiency for at least the first 72 hours following a disaster. In the face of pervasive environmental and weather hazards, emerging biological threats, and growing population densities in urban areas, personal preparedness is critical. However, disaster planners and policymakers require further information to create meaningful improvements to this aspect of disaster preparedness. A systematic review of the literature was conducted to determine the state of evidence concerning personal disaster preparedness. The purpose of this integrative review is to describe and analyze the professional literature as an intended basis for advancing the field of disaster management research and practice. Included in the review were 36 studies that met the predetermined inclusion criteria. The current evidence indicates that factors influencing preparedness attitudes and behaviors are complex and multifaceted, including demographic characteristics, trust in government efforts, previous exposure to a disaster, and number of dependents in a household. Furthermore, certain population groups, households, and individuals have different disaster preparedness needs and vulnerabilities. This constellation of findings has significant implications for community and national emergency planning and policymaking.
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http://dx.doi.org/10.1001/dmp.2012.47DOI Listing
October 2012

Multispectroscopic and molecular modeling approach to investigate the interaction of flavokawain B with human serum albumin.

J Agric Food Chem 2012 Jun 4;60(23):5899-908. Epub 2012 Jun 4.

Biomolecular Research Group, Biochemistry Programme, Institute of Biological Sciences, Faculty of Science, University of Malaya , 50603 Kuala Lumpur, Malaysia.

Interaction of flavokawain B (FB), a multitherapeutic flavonoid from Alpinia mutica with the major transport protein, human serum albumin (HSA), was investigated using different spectroscopic probes, i.e., intrinsic, synchronous, and three-dimensional (3-D) fluorescence, circular dichroism (CD), and molecular modeling studies. Values of binding parameters for FB-HSA interaction in terms of binding constant and stoichiometry of binding were determined from the fluorescence quench titration and were found to be 6.88 × 10(4) M(-1) and 1.0 mol of FB bound per mole of protein, respectively, at 25 °C. Thermodynamic analysis of the binding data obtained at different temperatures showed that the binding process was primarily mediated by hydrophobic interactions and hydrogen bonding, as the values of the enthalpy change (ΔH) and the entropy change (ΔS) were found to be -6.87 kJ mol(-1) and 69.50 J mol(-1) K(-1), respectively. FB binding to HSA led to both secondary and tertiary structural alterations in the protein as revealed by intrinsic, synchronous, and 3-D fluorescence results. Increased thermal stability of HSA in the presence of FB was also evident from the far-UV CD spectral results. The distance between the bound ligand and Trp-214 of HSA was determined as 3.03 nm based on the Förster resonance energy transfer mechanism. Displacement experiments using bilirubin and warfarin coupled with molecular modeling studies assigned the binding site of FB on HSA at domain IIA, i.e., Sudlow's site I.
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http://dx.doi.org/10.1021/jf301139hDOI Listing
June 2012

Laparoscopic cholecystectomy: an audit of 500 patients.

J Ayub Med Coll Abbottabad 2011 Oct-Dec;23(4):88-90

Department of Surgery, H. H. Sheikh Khalifa Bin Zayed Innahayan Hospital/AK CMH Muzaffarabad, Azad Jammu and Kashmir.

Background: The Gold standard treatment for symptomatic gallstone disease is laparoscopic cholecystectomy (LC) since 1990. LC can be performed safely as a day case procedure. The objective of this study was to evaluate the results of laparoscopic cholecystectomy in symptomatic gall stones disease in terms of length of hospital stay, complications, morbidity and mortality.

Methods: This retrospective descriptive study was carried out in Department of General & Laparoscopic Surgery, AK CMH, Muzaffarabad. Notes of all patients who underwent laparoscopic cholecystectomy in the department over a 26 month period were reviewed from department register. Demographics as well as details of cases, conversion to open operation and complications of surgery and anaesthesia were reviewed from clinical notes and departmental register and noted on a designed Performa. Data were analysed using SPSS-18 and results compared with international studies.

Results: Out of 500 patients, 443 (88.6%) were females and 57 (11.4%) were males. The mean age of the patients was 42.47 +/- 11.43 years. Mean operative time was 40.09 +/- 11.16 minutes. Seven (1.4%) patients developed port site wound infection. Sixteen (3.2%) cases were converted to open surgery in face of obscured anatomy of Calot's triangle. Two (0.4%) cases has cystic duct stoma leak secondary to missed Common duct stones and were dealt with ERCP and stone extraction. There was no case of bile duct injury, major haemorrhage or bowel injury. There was no mortality associated with laparoscopic cholecystectomy in our series.

Conclusion: Laparoscopic cholecystectomy is a safe and effective management of gall stone disease. Better training, careful case selection, meticulous technique and high standard equipment are of paramount importance for ensuring good results in laparoscopic cholecystectomy.
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April 2013

Protection against radiation-induced oxidative damage by an ethanolic extract of Nigella sativa L.

Int J Radiat Biol 2010 Sep;86(9):719-31

Radiation Biology and Health Sciences Division, Bhabha Atomic Research Center, Mumbai, India.

Purpose: An ethanolic extract of Nigella sativa L. (EE-NS) was investigated for its antioxidant properties and radioprotective effects against gamma-radiation-induced oxidative damage.

Materials And Methods: The radical scavenging activity of the extract was measured by 2,2-diphenyl-1-picrylhydrazyl (DPPH), deoxyribose degradation and plasmid relaxation assays in a cell-free system. DNA damage studies were performed using a single cell gel electrophoresis (SCGE) assay and micronuclei (MN) formation. Moreover, the alterations in lipid peroxidation and antioxidant enzymes were measured by biochemical methods.

Results: EE-NS showed significant free radical scavenging and protection against DNA damage in cell free systems. Ex vivo treatment of mouse splenic lymphocytes with an ethanolic extract of N. sativa 1 h prior to irradiation (2 Gy) showed significant prevention of the formation of lipid-peroxides and intracellular reactive oxygen species (ROS), which correlated with radiation-induced apoptosis. Moreover, radiation-induced DNA damage was significantly prevented in splenocytes pre-treated with EE-NS. Swiss albino mice fed orally with the different doses of EE-NS (0-100 mg/kg bw) for five consecutive days followed by 2 Gy whole body irradiation (WBI) showed significant protection against oxidative injury to spleen and liver as measured by lipid peroxidation and the activity of antioxidant enzymes. These results were correlated with the prevention of DNA damage as measured by bone marrow micronuclei assay. Our results suggest that oral feeding of extract resulted in increased survival in mice exposed to WBI (7.5 Gy).

Conclusion: The results obtained from the different experimental systems suggest the radioprotective ability of EE-NS involving prevention of radiation-induced oxidative damage.
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http://dx.doi.org/10.3109/09553002.2010.484480DOI Listing
September 2010

Simultaneous determination of gatifloxacin and ambroxol hydrochloride from tablet dosage form using reversed-phase high performance liquid chromatography.

Se Pu 2008 May;26(3):358-61

Maulana Azad Educational Trust's Y. B. Chavan College of Pharmacy, Dr. Rafiq Zakaria Campus, Rauza Bagh, Aurangabad-431001, Maharashtra State, India.

A reversed-phase high performance liquid chromatography (HPLC) method was developed, validated, and used for the quantitative determination of gatifloxacin (GA) and ambroxol hydrochloride (AM), from its tablet dosage form. Chromatographic separation was performed on a HiQ Sil C18 column (250 mm x 4.6 mm, 5 microm), with a mobile phase comprising of a mixture of 0.01 mol/L potassium dihydrogen orthophosphate buffer and acetonitrile (70 : 30, v/v), and pH adjusted to 3 with orthophosphoric acid, at a flow rate of 1 mL/min, with detection at 247 nm. Separation was completed in less than 10 min. As per International Conference on Harmonisation (ICH) guidelines the method was validated for linearity, accuracy, precision, limit of quantitation, limit of detection, and robustness. Linearity of GA was found to be in the range of 10 -60 microg/mL and that for AM was found to be 5 - 30 microg/mL. The correlation coefficients were 0.999 6 and 0.999 3 for GA and AM respectively. The results of the tablet analysis (n = 5) were found to be 99.94% with +/- 0.25% standard deviation (SD) and 99.98% with +/- 0.36% SD for GA and AM respectively. Percent recovery of GA was found to be 99.92% - 100.02% and that of AM was 99.86% - 100.16%. The assay experiment shows that the method is free from interference of excipients. This demonstrates that the developed HPLC method is simple, linear, precise, and accurate, and can be conveniently adopted for the routine quality control analysis of the tablet.
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http://dx.doi.org/10.1016/s1872-2059(08)60021-8DOI Listing
May 2008

Stand stratification and woody species diversity of a subtropical forest in limestone habitat in the northern part of Okinawa Island.

J Plant Res 2008 May 22;121(3):329-37. Epub 2008 Apr 22.

Laboratory of Ecology and Systematics, Faculty of Science, Graduate School of Engineering and Science, University of the Ryukyus, Okinawa, 903-0213, Japan.

Stand stratification and woody species diversity were studied in a subtropical forest in limestone habitat in the northern part of Okinawa Island, Japan. The forest stand consisted of four architectural layers. Cinnamomum japonicum Sieb. was the most dominant species as it had the highest importance value in all layers, especially in the lower three layers. Although Rhus succedanea L. was a major top-layer species, it might disappear because of its absence in the lower two layers. The lower two layers had similar floristic composition, while the composition of the top layer differed greatly from that of the lower two layers. The value of H' in each layer increased from the bottom to the second layer and then decreased, and the value of J' in each layer consistently increased from the bottom layer upward. The values of Shannon's index H' and Pielou's index J' were 4.27 bit and 0.74, respectively, at the stand level. The trends of H' and J' based on the cumulative height range from the top layer downward were, respectively, the same as those in each layer for the present forest in limestone habitat. However, these trends were opposite from those of a nearby subtropical forest in silicate habitat, where the values of H' and J' based on the cumulative height range decreased steadily from the bottom layer upward.
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http://dx.doi.org/10.1007/s10265-008-0162-zDOI Listing
May 2008

Treatment of metallic effluents using coconut shell coke.

J Environ Sci Eng 2005 Apr;47(2):109-14

Department of Chemical Engg, RVR & JC College of Engg, Guntur.

The effect of various parameters on the removal of metal ions (Zinc and Cadmium) by adsorption using coconut shell coke is investigated. The time of contact, initial metal ion concentration, adsorbent dosage, volume of the adsorbate solution, size of the adsorbent particle and the effect of the presence of another metal at various concentrations are the parameters studied. The adsorption isotherms so obtained in this study followed the Freundlich and Langmuir isotherms showing a marginal average deviation.
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April 2005

Stand structure and woody species diversity in relation to stand stratification in a subtropical evergreen broadleaf forest, Okinawa Island.

J Plant Res 2006 Jul 21;119(4):293-301. Epub 2006 Apr 21.

Laboratory of Ecology and Systematics, Faculty of Science, University of the Ryukyus, Okinawa 903-0213, Japan.

Stand structure and woody species diversity in a subtropical evergreen broadleaf forest grown in a silicate habitat, Okinawa Island, have been investigated on the basis of stand stratification. The forest stand consisted of four layers. The floristic composition of the top and the lower three layers was only slightly similar, although approximately one-third of the species were common to them. Mean tree weight decreased from the top toward the bottom layer whereas tree density increased from the top downward. This trend resembled the mean weight-density trajectory of self-thinning plant populations. The relationship between mean tree height and tree density for the upper two layers supported Yamakura's quasi -1/2 power law of tree height. The values of the Shannon-Wiener index, H', and the equitability index, J', tended to increase from the top layer downward except for the bottom layer. The values of H' and J' were, respectively, 4.83 bit and 0.82 for trees taller than 0.10 m. The lower layers contained many species of smaller height. High species diversity of the forest depended on small trees in the lower layers. Conservation of small trees in the lower layers, especially the bottom layer, is indispensable for sound maintenance of Okinawan evergreen broadleaf forests.
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http://dx.doi.org/10.1007/s10265-006-0270-6DOI Listing
July 2006
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