Properties of Bark Particleboard Bonded with Demethylated Lignin Adhesives Derived from Leucaena leucocephala Bark

Lignin extraction from bark can maximize the utilization of biomass waste,offer cost-effectiveness,and promote environmental friendliness when employed as an adhesive material in bark particleboard production.Particles of fine(0.2 to 1.0 mm),medium(1.0 to 2.5 mm),and coarse(2.5 to 12.0 mm)sizes,derived from the bark of Leucaena leucocephala,were hot-pressed using a heating plate at 175℃for 7 min to create single-layer particleboards measuring 320 mm×320 mm×10 mm,targeting a density of 700 kg/m^(3).Subsequently,the samples were trimmed and conditioned at 20℃and 65%relative humidity.In this study,we compared bark particleboard bonded with urea formaldehyde(UF)adhesive to fine-sized particleboard bonded with demethylated lignin adhesive.The results indicated that bark particleboards utilizing demethylated lignin and UF adhesives exhibited similar qualities.Coarse particleboard showed differences in modulus of elasticity(MOE)and modulus of rupture(MOR),while medium-sized particles exhibited significant variations in moisture content(MC)and water absorption(WA).Furthermore,the thickness swelling of coarse and medium-sized particles under wet and oven-dried conditions exhibited notable distinctions.Overall,the demethylated lignin adhesive extracted from L.leucocephala bark demonstrated similar quality to UF adhesive,with particle size correlating inversely to the strength of the bark particleboard.

Genetic diversity of the S-type small subunit ribosomal RNA gene of Plasmodium knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia

Objective:To determine the genetic diversity of Plasmodium(P.)knowlesi isolates from Sabah,Malaysian Borneo and Peninsular Malaysia,targeting the S-type SSU rRNA gene and including aspects of natural selection and haplotype.Methods:Thirty-nine blood samples infected with P.knowlesi were collected in Sabah,Malaysian Borneo and Peninsular Malaysia.The S-type SSU rRNA gene was amplified using polymerase chain reaction,cloned into a vector,and sequenced.The natural selection and haplotype of the S-type SSU rRNA gene sequences were determined using DnaSP v6 and illustrated using NETWORK v10.This study's 39 S-type SSU rRNA sequences and eight sequences from the Genbank database were subjected to phylogenetic analysis using MEGA 11.Results:Overall,the phylogenetic analysis showed no evidence of a geographical cluster of P.knowlesi isolates from different areas in Malaysia based on the S-type SSU rRNA gene sequences.The S-type SSU rRNA gene sequences were relatively conserved and with a purifying effect.Haplotype sharing of the S-type SSU rRNA gene was observed between the P.knowlesi isolates in Sabah,Malaysian Borneo,but not between Sabah,Malaysian Borneo and Peninsular Malaysia.Conclusions:This study suggests that the S-type SSU rRNA gene of P.knowlesi isolates in Sabah,Malaysian Borneo,and Peninsular Malaysia has fewer polymorphic sites,representing the conservation of the gene.These features make the S-type SSU rRNA gene suitable for comparative studies,such as determining the evolutionary relationships and common ancestry among P.knowlesi species.

Heavy metal pollution assessment in marine sediments in the Northwest coast of Sabah,Malaysia

Heavy metal contents along the Northwest coast of Sabah were determined to interpret the pollution level in the marine sediment. The metal abundance is regulated by the physico-chemical properties such as the average sediment pH(7.82, 9.00 and 8.99), organic matter(0.62%, 1.60%, and 2.27%), moisture content(25.00%, 29.70%, and 15.00%) and sandy texture in Kota Belud, Kudat and Mantanani Island,respectively. The major elements show Ca>Fe>Mg>Al>Mn for all study sites, while the heavy metals show Ni>Cr>Zn>Cu>Co>Pb, Cr>Ni>Zn>Cu>Pb>Co and Zn>Pb>Cr>Ni, for Kota Belud, Kudat and Mantanani Island, respectively. The pollution degree of heavy metals was evaluated by using the Sediment Quality Assessment(SQA). The SQA parameters indicated none to moderate pollution in Kota Belud that shows Class 0, Class 1 and Class 2 pollution. The parameters also indicated none to low pollution in Kudat and Mantanani Island that show only Class 0 pollution. The enrichment factor(EF) suggested minor to moderately severe metal enrichment by anthropogenic sources in Kota Belud, whereas only minor enrichment in Kudat and Mantanani Island. The modified pollution degree(MCD<1.5) and pollution load index(0 PLI<1) indicating only low pollution level in the marine sediments for all study sites. The objectives of this study are:(1) to determine the physico-chemical parameters of sediments,(2) interpret the heavy metal contents and(3) evaluate the sediment quality.

Contrasting Regional Responses of Indian Summer Monsoon Rainfall to Exhausted Spring and Concurrently Emerging Summer El Nino Events

The inverse relationship between the warm phase of the El Nino Southern Oscillation(ENSO)and the Indian Summer Monsoon Rainfall(ISMR)is well established.Yet,some El Nino events that occur in the early months of the year(boreal spring)transform into a neutral phase before the start of summer,whereas others begin in the boreal summer and persist in a positive phase throughout the summer monsoon season.This study investigates the distinct influences of an exhausted spring El Nino(springtime)and emerging summer El Nino(summertime)on the regional variability of ISMR.The two ENSO categories were formulated based on the time of occurrence of positive SST anomalies over the Nino-3.4 region in the Pacific.The ISMR’s dynamical and thermodynamical responses to such events were investigated using standard metrics such as the Walker and Hadley circulations,vertically integrated moisture flux convergence(VIMFC),wind shear,and upper atmospheric circulation.The monsoon circulation features are remarkably different in response to the exhausted spring El Nino and emerging summer El Nino phases,which distinctly dictate regional rainfall variability.The dynamic and thermodynamic responses reveal that exhausted spring El Nino events favor excess monsoon rainfall over eastern peninsular India and deficit rainfall over the core monsoon regions of central India.In contrast,emerging summer El Nino events negatively impact the seasonal rainfall over the country,except for a few regions along the west coast and northeast India.

沙巴地区新生代碎屑岩物源分析及构造意义:锆石年代学和Lu-Hf同位素组成约束

沙巴地区位于印度‒澳大利亚、太平洋和菲律宾海板块交汇区,其发育的新生代沉积对理解婆罗洲北部的沉积‒构造演化具有重要意义。本文对沙巴北部始新世‒中新世碎屑岩开展岩石学、锆石U-Pb年代学及Lu-Hf同位素研究,结果表明:该套碎屑岩包括岩屑石英砂岩和长石岩屑石英砂岩,其中始新统Trusmadi组碎屑锆石年龄主要峰值为160 Ma和120 Ma,对应年龄群(185~145 Ma和140~100 Ma)的εHf(t)值分别为–15.6~+14.8和+0.6~+12.2,表明源区新生地壳物质贡献明显。始新统‒中新统Crocker组碎屑锆石年龄主要峰值为248 Ma,次要峰值为1860 Ma、438 Ma、280 Ma和120 Ma,主要年龄群(265~220 Ma)的εHf(t)值为–11.9~+9.9。中新统Kudat组的碎屑锆石年龄集中在120 Ma、εHf(t)值(+1.8~+9.0)均为正值,次要峰值174 Ma。本次研究认为Trusmadi组砂岩物源主要受控于越南大叻带和婆罗洲西部中生代花岗质岩及古晋带再循环沉积物,Crocker组主要源自婆罗洲西部和马来半岛东部中生代火成岩,以及沙巴本身。Kudat组砂岩物源主要来自沙巴蛇绿岩及部分巴拉望陆块的再循环沉积物。此外,少量始新世岩浆成因碎屑锆石暗示沙巴地区存在始新世与古南海板块俯冲相关的岩浆作用。

ATP gatekeeper of Plasmodium protein kinase may provide the opportunity to develop selective antimalarial drugs with multiple targets

Malaria is one of the most devastating infectious diseases that caused millions of clinical cases annually despite decades of prevention efforts. Recent cases of Plasmodium falciparum resistance against the only remaining class of effective antimalarial(artemisinin) in South East Asia may soon pose a significant threat. Hence, the identification of new antimalarial compounds with a novel mode of action is necessary to curb this problem. Protein kinase has been implicated as a valid target for drug development in diseases such as cancer and diabetes in humans. A similar approach is now recognized for the treatment of protozoan-related disease including malaria. Few Plasmodium protein kinases that are not only crucial for their survival but also have unique structural features have been identified as a potential target for drug development. In this review, studies on antimalarial drug development exploiting the size of Plasmodium protein kinase ATP gatekeeper over the past 15 years are mainly discussed. The ATP-binding site of Plasmodium protein kinases such as Pf CDPK1, Pf CDPK4, Pf PKG, Pf PK7, and Pf PI4K showed great potential for selective and multi-target inhibitions owing to their smaller or unique ATP-gatekeeper amino acid subunits compared to that of human protein kinase. Hence it is a feasible solution to identify a new class of active antimalarial agents with a novel mode of action and longer clinical life-span.

Assessment of some chemical element contents in Traganum nudatum Del shrub using instrumental neutron activation analysis

Instrumental neutron activation analysis(INAA)has been used to determine some chemical element contents(K,Ca,Na,Fe,Zn,Co,Eu,Sb,and Sc)in Traganum nudatum Del(Chenopodiaceae family)consumed in North African rangelands by sheep livestock.Samples were collected from the area of Djelfa in an arid steppe of Algeria.Results show that pasture halophyte had sufficient levels of K,Ca,Zn,and Co to meet the requirements of ruminants.However,it seems that this halophyte shrub had substantial amounts of Na,higher than the critical level established by the National Research Council(NRC).Eu,Sb,and Sc were within the safety baseline of all the assayed elements recommended by the NRC.The high Na content(～10 g/kg)in this halophytic species requires elevated intake of water by livestock.

Essential Oils Leaf of <i>Cinnamomum glaucescens</i>and <i>Cinnamomum verum</i>from Vietnam

In this paper, compounds identified in the essential oils obtained by hydrodistillation of the leaves of Cinnamomum glaucescens (Nees) Hand.-Mazz and Cinnamomum verum J.S. Presl (Lauraceae family) of Vietnam origin are reported. The chemical analyses were performed using gas chromatography-flame ionisation detector (GC-FID) and gas chromatography coupled with mass spectrometry (GC-MS). The significant compounds of C. glaucescens were geraniol (36.2%) and terpinen-4-ol (19.7%). On the other hand, C. verum comprised of linalool (22.0%) and bicyclogermacrene (11.2%). The present results may represent new chemotypes of the essential oils of C. verum and C. glaucescens.

Seasonal variation of selected trace elements in rare endemic species Thuriferous Juniper growing in the Aurès Mountains of Algeria

We used energy dispersive X-ray fluorescence（EDXRF） to determine the seasonal variation of selected trace elements（Cr, Mn, Zn, Cu, Se and Fe） and some potential toxic elements（Cd, Pb and Br） in Juniperus thurifera subsp. africana Maire（Cupressaceae） a rare medicinal tree, growing indigenously in Aures Mountains of Algeria. The precision of the results was assessed by analyzing the certified reference material IPE44（WEPAL）grass leaves. Results showed J. thurifera was characterized by high Cr and Mn contents. During autumn and winter mineral concentrations were higher in general. The levels of Cr, Se and Mn were higher during autumn and winter than during spring and summer. Zn contents were higher during summer than in other seasons. Cu content did not vary by season. The potential toxic elements in J. thurifera（Pb [ Cd [ Br） were below the permissible limits recommended by the Joint WHO/FAO guidelines except for Pb in autumn and winter.

Causes of Cretaceous subduction termination below South China and Borneo:Was the Proto-South China Sea underlain by an oceanic plateau?

The South China,Indochina,and Borneo margins surrounding the South China Sea contain long-lived arcs that became inactive at approximately 85 Ma,even though an embayment of oceanic crust(the‘Proto-South China Sea’)remained in the intervening region.This oceanic crust eventually subducted in the Cenozoic below Borneo and the Cagayan arc,while the modern South China Sea opened in its wake.To investigate the enigmatic cessation of Mesozoic subduction below South China and Borneo,we studied a fragment of oceanic crust and overlying trench-fill sediments that accreted to NW Borneo during the final stages of Paleo-Pacific subduction.Based on radiolarian biostratigraphy of cherts overlying the pillow basalts and detrital zircon geochronology of the trench-fill,we constrained the minimum age of the oceanic crust during accretion to 40 Ma.This shows that subduction cessation was not related to ridge subduction.Geochemical analysis of pillow basalts revealed an enriched mid-ocean ridge basalt signature comparable to oceanic plateaus.Using paleomagnetism,we show that this fragment of oceanic crust was not part of the Izanagi Plate but was part of a plate(the‘Pontus’Plate)separated from the Izanagi Plate by a subduction zone.Based on the minimum 40 Ma age of the oceanic crust and its geochemistry,we suggest that Mesozoic subduction below South China and Borneo stopped when an oceanic plateau entered the trench,while the eastern plate margin with the Izanagi Plate remained active.We show how our findings offer opportunities to restore plate configurations of the Panthalassa-Tethys junction region.

Surface ozone variations at the Great Wall Station,Antarctica during austral summer

Surface ozone(O3)is a secondary pollutant harmful to human health and a greenhouse gas which is one of the prime climate forcers.Due to the clean atmospheric environment of the Antarctic region and given the complexity of O3 chemistry,the observation of surface O3 variability in this region is necessary in the quest to better understand the potential sources and sink of polar surface O3.In this paper,we highlighted our observations on O3 variability at the Great Wall Station(GWS)during austral summer in December 2018 and January 2019.The continuous surface O3 measurement at the GWS,Antarctica was carried out using the Ecotech Ozone analyzer.To understand the roles of the meteorological conditions on the temporal variations of O3,meteorological data was obtained from the conventional auto-observational station at the GWS.The Hybrid Single-Particle Lagrangian Integrated Trajectory(HYSPLIT)model was employed to investigate the air mass transport over the region.The observed austral summer surface O3 concentrations at the GWS exhibited variability and were significantly lower than those previously observed at other permanent coastal stations in Antarctica.The surface ozone variability at the GWS was strongly influenced by the synoptic change of air mass origin although the roles of photochemistry production and destruction were still uncertain.Marine characteristics and stable surface O3 characterized the air masses that reached the GWS.The unique characteristic of surface O3 at the coastal site of GWS was emphasized by its synoptic air mass characteristics,which displayed a significant influence on surface O3 variability.Air mass that traveled over the ocean with relatively shorter distance was linked to the lower O3 level,whereby the marine transport of reactive bromine(Br)species was thought to play a significant role in the tropospheric chemistry that leads to O3 destruction.Meanwhile,the diurnal variation indicated that the O3 background concentration levels were not strongly associated with the local atmospheric conditions.

Observed Trends in Extreme Temperature over the Klang Valley, Malaysia

This study investigates the recent extreme temperature trends across 19 stations in the Klang Valley, Malaysia, over the period 2006^-16. Fourteen extreme index trends were analyzed using the Mann-Kendall non-parametric test, with Sen’s slope as a magnitude estimator. Generally, the annual daily mean temperature, daily mean maximum temperature, and daily mean minimum temperature in the Klang Valley increased significantly, by 0.07°C yr^-1, 0.07°C yr^-1 and 0.08°C yr^-1, respectively. For the warm temperature indices, the results indicated a significant upward trend for the annual maximum of maximum temperature, by 0.09°C yr^-1, and the annual maximum of minimum temperature, by 0.11°C yr^-1. The results for the total number of warm days and warm nights showed significant increasing trends of 5.02 d yr^-1 and 6.92 d yr^-1, respectively. For the cold temperature indices, there were upward trends for the annual minimum of maximum temperature, by 0.09°C yr^-1, and the annual minimum of minimum temperature, by 0.03°C yr^-1, concurrent with the decreases in the total number cold days (TX10P), with -3.80 d yr^-1, and cold nights (TN10P), with -4.33 d yr^-1. The 34°C and 37°C summer days results showed significant upward trends of 4.10 d yr^-1 and 0.25 d yr^-1, respectively. Overall, these findings showed upward warming trends in the Klang Valley, with the minimum temperature rate increasing more than that of the maximum temperature, especially in urban areas.

西南婆罗洲中生代构造归属:班达弧vs.印支陆块?

西南婆罗洲施瓦纳山杂岩体作为婆罗洲最大的岩体,保存了丰富的中生代岩浆记录,是研究中生代古太平洋俯冲体系表现形式的关键区域.但是以往对中生代西南婆罗洲构造归属的讨论存在班达弧和印支陆块两种截然不同的认识.为此,本文选取了施瓦纳山杂岩体中新识别的晚白垩世中-基性火成岩开展了系统的年代学、主-微量元素和Sr-Nd-Pb-Hf同位素研究.锆石年代学研究表明该套晚白垩世中-基性火成岩形成于101~90 Ma.该套火山岩具有高镁火成岩的特征,以富集大离子亲石元素和轻稀土元素、亏损高场强元素(Nb、Ta和Ti)为特征,具有岛弧岩浆岩的配分模式.它们的初始(87Sr/86Sr)i=0.70450~0.70635,εNd(t)=–1.6~+1.7,锆石原位εHf(t)=–0.9~+12.3,其初始(206Pb/204Pb)i=18.73~18.83,(207Pb/204Pb)i=15.66~15.67,(208Pb/204Pb)i=38.78~39.88,显示出类似太平洋洋中脊玄武岩型的Pb同位素组成.地球化学数据表明,该套中-基性火成岩源自俯冲板片派生组分交代的地幔楔源区.区域对比研究表明,西南与西北婆罗洲的侏罗纪至白垩纪岛弧火成岩均具有相似的Sr-Nd-Pb-Hf同位素组成和一致的岩浆作用期次(85、110、135和155 Ma),说明在西南与西北婆罗洲之间缺乏早中生代时期的缝合边界,证实了西南婆罗洲并非起源自班达弧,两者一起在晚白垩世时期共同受到了古太平洋西向的俯冲-回撤作用.

Kenaf cellulose-based poly(amidoxime) ligand for adsorption of rare earth ions

A well-known adsorbent, poly(amidoxime)ligand, was prepared from polyacrylonitrile(PAN) grafted kenaf cellulose, and subsequent characterization was performed by Fourier transform infrared spectroscopy(FTIR),field emission scanning electron microscope(FESEM) and inductively coupled plasma mass spectrometry(ICP-MS).The adsorption capacities of the prepared ligand for rare earth metals are found to be excellent, with adsorptions of La^(3+), Ce^(3+), Pr^(3+), Gd^(3+) and Nd^(3+) experimentally determined to be 262, 255, 244, 241 and 233 mg·g^(-1), respectively, at pH 6. The experimental values of the adsorption of rare earth metals are well matched with the pseudosecond-order rate equation. The reusability of the adsorbent is examined for seven cycles of sorption/desorption,demonstrating that the proposed adsorbent could be reused for over seven cycles without any significant loss in the original removal capability of the ligand.

Synthesis of ion imprinted polymers for selective recognition and separation of rare earth metals

Lanthanide-ion imprinted polymers（L-IIPs） were synthesized by stoichiometric amounts of rare earth ions and the cavities in the polymers were created for the corresponding lanthanide ions. The maximum sorption capacities were estimated to be 125.3, 126.5, 127.6, 128.2 and 129.1 mg/g for Pr, Nd, Sm, Eu and Gd, respectively at p H 6. In the selectivity study, the L-IIPs exhibited good selectivity to the specific rare earth ions in the presence of coexisting cations. The imprinting results were found to be excellent with some rare earth ions over other competitor rare earth ions with the same charges and close ionic radius.

Chemical characterization, release, and bioactivity of Eucalyptus camaldulensis polyphenols from freeze-dried sodium alginate and sodium carboxymethyl cellulose matrix

Crude ethanolic extract of Eucalyptus camaldulensis was encapsulated with sodium alginate- sodium carboxymethyl cellulose (CMC) using freeze-drying techniques. The microcapsules were characterized for particle size, morphology, physicochemical parameters, and micromeritics properties. Antioxidant and antimicrobial activities of the microcapsules were also demonstrated. Results revealed an irregular-shaped microparticles with a mean diameter ranging from 6.7 to 26.6 μm. Zeta potential and polydispersity index ranged from −17.01 to 2.23 mV and 0.34 to 0.49, respectively. Percentage yield ranged between 70.4 and 81.5 per cent whereas encapsulation efficiency ranged between 74.2 ± 0.011 and 82.43 ± 0.77 per cent. Swelling index and solubility varied inversely with extract concentration, with a range of 54.4%-84.0% and 18.8%-22.2%, respectively. Antioxidant activities varied directly with the concentration of the extract. Minimum inhibitory and minimum bactericidal concentrations of the microcapsules against Gram-positive foodborne pathogens ranged from 0.19 to 3.12 and 0.19-12.25 mg/ml, respectively. The Higuchi model indicated a time-dependent, delayed, and regulated release of polyphenols at 37°C. The results suggested that alginate-CMC possessed good encapsulant properties that preserved the bioactive extract, thus might be employed for application of natural products in food systems.

Understanding the economic impacts of sea-level rise on tourism prosperity:Conceptualization and panel data evidence

Sea-level rise is a long-term,intractable problem during which costly,large-scale inundation could occur in many countries;hence,tourismdevelopment should take this matter into account because ecology and biodiversity are the fundamentals underpinning tourism performance.This study conceptualizes an economic mechanism of the potential effects of sea-level rise on tourism development based on projected impactsfor the 2001e2100 period.Data for 48 developing countries across Africa,Asia,and South America are analyzed.The theoretical frameworkproposes two hypotheses to determine the extent of contradiction between awareness and destruction in relation to environmental protection fortourism development.From the panel data regression results,although destructive effects are bound to dominate the entire 21st century,awareness is latent and has the potential to reverse the destructive outcomes.With evidence from essential economic elements,this study givesnew insights into how severe the impacts of sea-level rise on tourism could be if shared values and adaptation measures to mitigate rising sealevel are not substantively promoted around the globe.The new findings show a 0.95 standard-deviation decrease in tourism performancefollowing a 1 standard-deviation increase in the economic loss related sea-level rise.Hence,in the main conclusions,we highlight that theprojected effect of inundation-related deterioration on a country's tourism sector appears to be approximately on par with the costs of inundationsto its economic growth.

Monitoring the impact of Movement Control Order (MCO) in flattening the cummulative daily cases curve of Covid-19 in Malaysia: A generalized logistic growth modeling approach

Introduction:COVID-19 has affected almost every country in the world,which causing many negative implications in terms of education,economy and mental health.Worryingly,the trend of second or third wave of the pandemic has been noted in multiple regions despite early success of flattening the curve,such as in the case of Malaysia,post Sabah state election in September 2020.Hence,it is imperative to predict ongoing trend of COVID-19 to assist crucial policymaking in curbing the transmission.Method:Generalized logistic growth modelling(GLM)approach was adopted to make prediction of growth of cases according to each state in Malaysia.The data was obtained from official Ministry of Health Malaysia daily report,starting from 26 September 2020 until 1 January 2021.Result:Sabah,Johor,Selangor and Kuala Lumpur are predicted to exceed 10,000 cumulative cases by 2 February 2021.Nationally,the growth factor has been shown to range between 0.25 to a peak of 3.1 throughout the current Movement Control Order(MCO).The growth factor range for Sabah ranged from 1.00 to 1.25,while Selangor,the state which has the highest case,has a mean growth factor ranging from 1.22 to 1.52.The highest growth rates reported were inWP Labuan for the time periods of 22 Nov-5 Dec 2020 with growth rates of 4.77.States with higher population densities were predicted to have higher cases of COVID-19.Conclusion:GLM is helpful to provide governments and policymakers with accurate and helpful forecasts on magnitude of epidemic and peak time.This forecast could assist government in devising short-and long-term plan to tackle the ongoing pandemic.

Parameter identification of partially covered piezoelectric cantilever power scavenger based on the coupled distributed parameter solution

Among the various techniques of power scavenging,piezoelectric energy harvesting usually has more power density.Although piezoceramics are usually more efficient than other piezoelectric materials,since they are very brittle and fragile,researchers are looking for alternative materials.Recently Cellulose Electro-active paper(EAPap)has been recognized as a smart material with piezoelectric behavior that can be used in energy scavenging systems.The majority of researches in energy harvesting area,use unimorph piezoelectric cantilever beams.This paper presents an analytical solution based on distributed parameter model for partially covered pieoelectric cantilever energy harvester.The purpose of the paper is to describe the changes in generated power with damping and the load resistance using analytical calculations.The analytical data are verified using experiment on a vibrating cantilever substrate that is partially covered by EAPap films.The results are very close to each other.Also asymptotic trends of the voltage,current and power outputs are investigated and expressions are obtained for the extreme conditions of the load resistance.These new findings provide guidelines for identification and manipulation of effective parameters in order to achieve the efficient performance in different ambient source conditions.

CD4 cell activation with the CD8 marker and metallothionein expression in the gills of cadmium-exposed mosquito fish(Gambusia affinis Baird and Girard 1853)juveniles

This experiment aimed to determine how Cd exposure impacts CD4 cell activation,macrophage cells,pinocytosis activity,metallothionine expression,and Cd levels in juvenile Gambusia affinis gills.Four treatment groups were used,with one control and treatments A,B,C,and D at dosages of 0.03 mg/L,0.023 mg/L,0.015 mg/L,and 0.008 mg/L,respectively.The results showed that the number of CD4 with CD8 cell markers differed significantly from each treatment compared to the control(0.33%).The value in A,namely 0.54%,was the highest,followed by B,C,and D of 0.46%,0.44%,and 0.42%,respectively.The number of macrophages increased as the Cd level of the medium increased,as did the activity of pinocytosis.Furthermore,the immunofluorescence test on the gills with the Anti-MT Mouse and goat IgG fluoresce in Rhodamine on the gills showed that luminescence increased with increasing Cd levels in the gills.Similarly,the MT intensity increased at Cd-exposed gills as compared to the control.As the Cd level in the gills increased,the MT levels ascended significantly.