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Characterization of Cassava Root Husk Powder: Equilibrium, Kinetic and Modeling Studies as Bioadsorbent for Copper(II) and Lead(II)

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Journal of Encapsulation and Adsorption Sciences 2021年第2期11卷 69-86页

作者： Kaupa Philip rebecca jacob Janarthanan Gopalakrishnan Department of Applied Sciences PNG University of Technology Lae Papua New Guinea School of Chemistry University of Sydney Sydney Australia

This study was aimed to investigate Pb(II) and Cu(II) ions removal ability from aqueous solution by cassava root husks (CRH) as a cheap, sustainable and eco-friendly bioadsorbent. The CRH was characterized by Fourier Transform Infrared (FTIR) spectroscopy which indicated the availability of various functional groups for metal coordination and the result was supported by elemental analysis studies. UV-Visible spectral studies indicated the presence of oxalate () and it could possibly interact with metal ions to give rise to a stable chelated coordination complex which affects metal ions removal efficiency. Bioadsorption process was carried out as a function of metal concentration, contact time, pH of the solution, particle size, and dosage of the adsorbent. Experimental results indicated the optimal adsorption condition of pH 4 for both Pb(II) and Cu(II) ions, dosage of 0.1 g/0.1L and 1 g/0.1L for Pb(II) and Cu(II) ions respectively, adsorption equilibrium time of 2 and 25 minutes for Pb(II) and Cu(II) respectively, and concentration of 0.5 mg/L for both metal ions. Kinetic data best fitted pseudo-second-order model and not the pseudo-first-order model. Equilibrium data best fitted the Freundlich model than the Langmuir model. Specific surface area and pore volume studies indicated that CRH is non-porous and hence rapid adsorption kinetics is expected. Supporting the experimental results, molecular modeling studies performed using Schrödinger software predicted several sites in the structu

关键词： Bioadsorption Langmuir Isotherm Freundlich Isotherm Pseudo-First-Order Kinetics Pseudo-Second-Order Kinetics Cassava Root Husk Molecular Modeling

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Temporal variability and sources of PFAS in the Rio Grande,New Mexico through an arid urban area using multiple tracers and highfrequency sampling

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Emerging Contaminants 2024年第3期10卷 205-220页

作者： Kimberly R.Beisner rebecca E.Travis David A.Alvarez Larry B.Barber jacob A.Fleck Jeramy R.Jasmann U.S.Geological Survey 6700 Edith Blvd NEAlbuquerqueNM87113USA U.S.Geological Survey 4200 New Haven RoadColumbiaMO65201USA U.S.Geological Survey 3215 Marine St.BoulderCO80303USA U.S.Geological Survey 6000 J St.Placer Hall.SacramentoCA95819USA

Per-and polyfluoroalkyl substances(PFAS)are ubiquitous in the environment but sources are not well defined for temporal and spatial aspects within an urban environment,and especially for an arid urban environment subject to seasonal short term high-intensity precipitation events.A focused diel sampling was conducted in the summer of 2021 to assess the temporal and spatial variability of PFAS in the Rio Grande near Albuquerque,New Mexico and showed an order of magnitude increase of PFAS as it flows through the Albuquerque urban *** samples were collected at two different locations on the Rio Grande in addition to wastewater treatment plant(WWTP)effluent that discharges directly to the Rio Grande between the sampling ***-term high-intensity precipitation events occurred during the study period and mobilized PFAS from urban *** organic matter composed of tryptophan-like organic substances and refined fuel and fuel byproducts,characteristic of an urban signature,were also related to the precipitation *** PFAS in discharge from the WWTP was consistent over a 24-h period with slight differences in some *** presence on the Rio Grande downstream of the WWTP was evidenced by a gadolinium anomaly as well as increases in several other trace elements,total dissolved nitrogen,and fluorescence indicators,in addition to *** varied depending on source contribution,where urban runoff was associated with PFOA,PFOS,and PFBA,whereas PFHxA and PFPeA were associated with wastewater *** addition,passive polar organic chemical integrative samplers(POCIS)using hydrophilic-lipid balance(HLB)sorption media were deployed for a month at two locations on the Rio Grande to assess longer term PFAS *** POCIS results show some compounds(PFPeA and PFHpA)were greater than the average concentration from discrete samples,whereas other compounds(PFHxA,PFOA,PFDA,and PFNA)were lower in the POCIS,and PFOS was very simila

关键词： wastewater Rio runoff

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Climate drives differences in the germination niche of a globally distributed invasive grass

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Journal of Plant Ecology 2020年第2期13卷 195-203页

作者： rebecca A.Fletcher Kayla M.Varnon jacob N.Barney Virginia Tech School of Plant and Environmental Sciences675 Old Glade RdBlacksburgVA 24061USA

Aims Exotic invasive species are often exposed to strong selection pressures in their new ranges that can often lead to substantial intraspecific *** differentiation in the timing of life history events in response to climate gradients is thought to be an important mechanism facilitating the range expansion of many invasive *** seed producing plants,the timing of seed germination determines the first environmental conditions experienced by newly emerged germinates,and can have important implications for the successful colonization,establishment and spread of invasive plants—though the role of germination in the success of invasive plants remains poorly *** We assessed the variation in seed germination dynamics among 10 populations of the invasive plant Johnsongrass(Sorghum halepense)across its North American distribution,capturing both a temperature and precipitation gradient,and whether that variation is associated with home *** were exposed to a wide range of temperatures(11–48℃)and two water availability *** Findings We found that Johnsongrass seeds germinated across a wide range of temperatures,but there was substantial variation among populations in the proportion of seeds that germinated in response to both temperature and water *** indicates that as Johnsongrass expanded its range from warmer climates into cooler climates,there was a concurrent shift in the germination temperature niche to cooler *** results suggest that the germination of Johnsongrass seeds has adapted to home climate allowing this invader to maximize germination throughout its range,and that this may be an important contributing factor to its invasion into new environments.

关键词： adaptation among-population variation Johnsongrass Sorghum halepense temperature water availability

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Evidence for fine-scale habitat specialisation in an invasive weed

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Journal of Plant Ecology 2018年第2期11卷 189-199页

作者： Daniel Z.Atwater rebecca A.Fletcher Christopher C.Dickinson Andrew H.Paterson jacob N.Barney Virginia Tech Department of Plant PathologyPhysiology and Weed Science435 Old Glade RoadBlacksburgVA 24061USA University of Georgia Plant Genome Mapping Laboratory111 Riverbend RoadAthensGA 30606USA

Aims As an exotic species colonises a new continent,it must overcome enormous environmental variation in its introduced *** adaptation of introduced species has frequently been observed at the continent scale,particularly in response to latitudinal climatic ***,significant environmental heterogeneity can also exist at the landscape scale.A small number of studies have provided evidence that introduced species may also be capable of phenotypic and genetic differentiation at much smaller spatial *** example,previously we found US agricultural and non-agricultural populations of Sorghum halepense(Johnsongrass)to be phenotypically and genetically *** this study,we inves-tigated whether this phenotypic differentiation of agricultural and non-agricultural populations of *** is the result of fine-scale local *** We surveyed a nationally collected *** germplasm panel and also collected neighbouring agricultural and non-agricultural sub-populations of *** at four sites throughout Western Virginia,USA,raising seedlings in common conditions mimicking both agricultural and non-agricultural *** Findings At the national scale,we found evidence of habitat differentiation but not ***,at the local scale,we found evi-dence of specialisation in two of the four local populations to non-agricultural habitat,but no evidence of specialisation to agricultural *** results show that local specialisation is a possible,but not guaranteed consequence of kilometre-scale habitat heterogen-eity in invasive *** finding contributes to a growing aware-ness of the importance of fine-scale local adaptation in the ecology and management of introduced and weedy species.

关键词： Johnsongrass local adaptation rapid evolution Sorghum halepense(L.)

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美国大陆五个山区集水区的河溪结构分析(英文)

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生态学报 1999年第1期19卷 30-41页

作者：陈吉泉 H.Alexes Londo rebecca A.Megown 张全发 William J.Boelema Ann M.Hoefferle jacob J.LaCroix Andy J.Londo Krista A.Markovic Michelle L.Olson School of Forestry and Wood Products Michigan Technological University 美国

河溪结构及其关联的空间特征，是研究集水区中能量和物质移动规律所不可缺少的内容。利用美国地质调查局的水文数据库和地理信息系统（ＡＲＣ／ＩＮＦＯ），对美国大陆５个主要山地中典型集水区河溪的数量、密度、分布结构以及河溪岸边... 详细信息

河溪结构及其关联的空间特征，是研究集水区中能量和物质移动规律所不可缺少的内容。利用美国地质调查局的水文数据库和地理信息系统（ＡＲＣ／ＩＮＦＯ），对美国大陆５个主要山地中典型集水区河溪的数量、密度、分布结构以及河溪岸边带的组成，进行了分析和比较。５个山地分别是：西北太平洋沿岸，西部卡斯卡特山，中部落矶山，东部阿巴拉契亚山和南部欧扎克山。发现这５个集水区中的河溪网络结构非常相似，一级河溪大约占河溪总长度的６０％左右。东部山地地质历史比较长，其集水区中河溪总长度、密度，高差以及河溪片段数量，都比西部相对年轻的集水区要高。此外，尽管其中河溪边岸域总面积随边岸域宽度线性增长，但它们在面积中的相对比例仍然很小（＜１２％）。因此，在森林经营中保护河溪边岸植被。

关键词：河溪结构山区集水区美国

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奥拉帕利维持治疗BRCA 1/2突变铂敏感复发性卵巢癌患者(SOLO2/ENGOT-Ov21):一项双盲随机对照Ⅲ期试验的最终分析

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肿瘤药学 2021年第3期11卷 275-279页

作者： Andrés Poveda Anne Floquet Jonathan A Ledermann rebecca Asher Richard T Penson Amit M Oza jacob Korach Tomasz Huzarski Sandro Pignata Michael Friedlander Alessandra Baldoni Tjoung-Won Park-Simon Kenji Tamura Gabe S Sonke Alla Lisyanskaya Jae-Hoon Kim Elias Abdo Filho Tsveta Milenkova Elizabeth S Lowe Phil Rowe Ignace Vergote Eric Pujade-Lauraine the SOLO/ENGOT-Ovinvestigators 王娟(校) 李征(校) 不详

背景既往发表的SOLO2/ENGOT-Ov21试验的第一部分研究结果表明,作为BRCA1或BRCA2(BRCA1/2)突变铂敏感型的高级别浆液性或子宫内膜样卵巢癌复发患者使用奥拉帕利可延长无进展生存期。因此,本研究的最终分析目的是研究奥拉帕利对这类患者... 详细信息

背景既往发表的SOLO2/ENGOT-Ov21试验的第一部分研究结果表明,作为BRCA1或BRCA2(BRCA1/2)突变铂敏感型的高级别浆液性或子宫内膜样卵巢癌复发患者使用奥拉帕利可延长无进展生存期。因此,本研究的最终分析目的是研究奥拉帕利对这类患者总生存期的影响。方法本研究是一项在16个国家123个医疗中心进行的双盲、随机、安慰剂对照、Ⅲ期临床试验。纳入标准包括:年龄≥18岁;ECOG体能状态评分基线水平为0~1分;组织学检查确诊为复发性、高级别浆液性或高级别子宫内膜样卵巢癌,包括原发性腹膜癌或输卵管癌;以及既往接受过2种或2种以上铂类药物的治疗方案。入选患者按2∶1分配到奥拉帕利组(150 mg片剂,每日2次口服,共300 mg)或安慰剂组;根据既往化疗后是否缓解以及无铂治疗间隔时长进行分层;受试者、治疗提供者和数据分析人员在治疗分配时均设盲。主要终点是既往已报道过的无进展生存期;总生存期作为重要的次要终点之一,在所有随机分配的患者中进行分析;安全性评估在至少接受过1次给药的所有患者中进行。结果2013年9月3日—2014年11月21日,共295例患者参与了试验并被随机分到奥拉帕利组(196例,66%)或安慰剂组(99例,34%)治疗。奥拉帕利组患者中位随访时间为65.7个月(IQR:63.6~69.3),安慰剂组为64.5个月(IQR:63.4~68.7)。奥拉帕利组中位总生存期为51.7个月(95%CI:41.5~59.1),安慰剂组为38.8个月(95%CI:31.4~48.6)(HR=0.74,95%CI:0.54~1.00,P=0.054)。安慰剂组38%接受PARP抑制剂治疗的患者未作调整。治疗引发的最常见的Ⅲ级以上不良事件为贫血,奥拉帕利组发生率为21%(41/195),安慰剂组为2%(2/99)。

关键词：安慰剂 Ⅲ期临床试验输卵管癌铂类药物患者参与组织学检查 BRCA SOLO

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