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There is considerable interest in the plant family Amaryllidaceae for its biologically-active isoquinoline alkaloid principles. Some of these (such as galanthamine and narciclasine) have demonstrated their applicability in the clinical arena, particularly as cancer and motorneuron disease therapeutics. While synthetic organic chemistry affords ideal opportunities for drug development with such targets, the phytochemical approach is considered a somewhat more amenable option. In this regard, southern Africa has garnered widespread attention due to the abundance of Amaryllidaceae plants in its territory. Crinum, Ammocharis, Amaryllis, Cyrtanthus and Brunsvigia are genera of the family that are likewise well-represented in southern Africa. Up to 2012, thirty members from these genera were examined for their chemical and biological properties, culminating with the identification of nearly one-hundred alkaloid entities several of which exhibited notable biological activities. The present effort covers studies since 2013 that have been undertaken on the title genera in regards to their chemical and biological characteristics. Close to ninety alkaloids and twenty-five non-alkaloid entities were described during this time-frame from fifteen representative species. Biological studies included cholinesterase inhibiton, cytotoxicity, antidiabetes and antihypertensive effects, herbicidal, insecticidal and plant growth regulatory effects, as well as anti-inflammatory, antioxidant and antiplasmodial effects. The structural variety of the compounds isolated in cases allowed for structure-activity probes to be made in some of the assays. There were also studies carried out to establish the molecular basis to these activities, notably in the area of molecular cancer chemotherapeutics.

Stimulated by the promising results seen for its phenanthridones in clinical trials, interest in the Amaryllidaceae as a potential source of anticancer drugs has intensified in recent years. As such, over three hundred isoquinoline principles from its various alkaloid groups have to date been screened against a large number of cancer cell lines. Whilst significant effort has been diverted towards studies of lycorine and its congeners, the closely-allied homolycorine alkaloids of this plant family have largely been overlooked. These compounds have often been used as supporting acts to bolster the diversity of structures in cytotoxicity studies of the more recognized phenanthridone, lycorane and crinane alkaloids of the Amaryllidaceae. This notwithstanding, a substantial amount of information has surfaced over the past several years on such effects for the homolycorine alkaloids. This review takes a detailed look at the cytotoxic effects manifested by over forty of these alkaloids against around sixty cell lines, which may be classified into eighteen different types of cancers. In this regard, good activities were detected for some constituents (such as lycorenine and hippeastrine) against various hepatic and prostate cancers. The structural features which support and fortify the efficacy of the homolycorine alkaloid cytotoxic pharmacophore are also considered. These include the ways in which the innate ring systems are appended as well as the size, geometry and electronics of the attendant substituents. In addition, the various mechanisms used to rationalize the cytotoxic responses are described notably, interaction with DNA, apoptosis induction, protection from tumor invasion, efflux pump perturbation and topoisomerase inhibition.

From camptothecin to vinblastine, plant alkaloids continue to capture the imagination of scientists as a valuable source of anticancer drugs. Given that they are also amongst the most common secondary metabolites encountered in plants, the number of alkaloid entities subjected to cytotoxicity evaluations now runs into several thousands. Interest in the plant family Amaryllidaceae has been persistent owing to the potent cytotoxic activities of several of its isoquinoline alkaloid principles. This survey is an indepth account of such properties discernible for tazettine alkaloids belonging to the minor alkaloid groups of the Amaryllidaceae. Eleven of such compounds have up to now been screened against around 50 cancer cell lines which may be classified into nearly 20 different types of cancers. Although the activities in most instances were moderate to mild, notable responses were observed against some leukemia, adenocarcinoma, lymphoma and glioblastoma cell lines. In fact, pretazettine (ED50 0.3 μg/mL) was amongst the most potent of all Amaryllidaceae alkaloids screened against the human Molt4 T-lymphoma cell line. To most accounts, the parent compounds (such as tazettine and pretazettine) with their distinct ring systems and substitution patterns exhibit the best activities, offering little space for structural adjustments via semi-synthetic operations. Several avenues have been probed in attempts to elucidate the mechanisms by which tazettine alkaloids manifest their cytotoxic effects including, inhibition of protein synthesis, apoptosis and efflux pump interactions, the first of which to date offers the most profound insights.

Viral-borne diseases are amongst the oldest diseases known to mankind. They are responsible for some of the most ravaging effects wrought on human health and well-being. The use of plants against these ailments is entrenched in both traditional and secular medicine around the globe. Their natural abundance and chemical diversity have also boosted their appeal in drug discovery.The plant family Amaryllidaceae is distinguished for its alkaloid principles, some of which are of considerable interest in the clinical arena. This account is the outcome of a literature review undertaken to establish the applicability of these substances as antiviral agents.The survey utilized the search engines Google Scholar, PubMed, SciFinder, Scopus and Web of Science engaging the word 'antiviral' in conjunction with 'Amaryllidaceae' and 'Amaryllidaceae alkaloid'. The search returned over five hundred hits, of which around eighty were of relevance to the theme of the text.Over eighty isoquinoline alkaloids have been screened against nearly fifty pathogens from fourteen viral families, the majority of which were RNA viruses. Potent activities were reported in some instances, such as that of trans-dihydronarciclasine against Yellow fever virus (ICThe Amaryllidaceae offers a viable platform for plant-based antiviral drug discovery. Its cause is strengthened not only by its wide proliferation and exploitation of its members in alternative forms of medicine, but also by its rich chemical diversity which has already spawned useful antiviral drug leads.

There are subtle mechanisms at work in nature to maintain a balance in the interactions between plants and animals. The production of secondary metabolites is one of the key strategies utilized by plants to minimize their over-exploitation. The ‘lily borer’ moth Brithys crini poses a considerable challenge to Amaryllidaceae plants owing to the devestation it can cause during the larval stage of its development. This, despite the fact that the Amaryllidaceae is richly endowed with an assortment of isoquinoline alkaloid constituents which exhibit a diverse array of biological properties, particularly cytotoxicity-related effects. In this study, laboratory-maintained larvae of B. crini were periodically fed fresh leaves of Crinum moorei during the September to November infestation period in Pietermaritzburg, South Africa. Solvent extracts of the plant leaves, moth larvae and larvae excrement material were then prepared and subjected to HPLC and LC–MS analyses. The presence of several alkaloids, including cherylline and ambelline, in all three extracts was ratified via HR-MS and NMR analyses. The identification of ambelline is noteworthy since it has not been reported in previous studies of C. moorei. Toxicity related criteria are also considered based on the present detection of alkaloids in B. crini larvae material, as well as precedence for their association with other known insect predators of the Amaryllidaceae.

Malaria is responsible for majority of the morbidity and mortality statistics reflected by tropical diseases. Whilst effectively managed in most parts of the globe, it remains a scourge on the African continent where most cases of the disease are diagnosed annually. Plants have played a leading role as a source of malarial drugs which continue to dominate the clinical landscape today. Most if not all of these discoveries have as their basis evidence which can be traced back to traditional medicine. There is likewise precedence for the use of Amaryllidaceae plants in traditional medicinal approaches towards malaria. The chief phytochemical principles of the Amaryllidaceae are its isoquinoline alkaloids which are responsible for its diverse biological properties. These alkaloids may be divided into major and minor groups based on their distinguishing structural features as well as their natural abundance and distribution in the family. Whilst much has been written about the biological and chemical properties of the major alkaloid groups of the Amaryllidaceae, relatively little is known or understood about its minor alkaloid groups. This review focuses on the antiplasmodial activities described in the literature for the minor alkaloid group members of the Amaryllidaceae against various strains of the malarial pathogen Plasmodium falciparum . Three database platforms (Google Scholar, SciFinder and Scopus) were utilized for the literature search. Articles were accessed from journals licensed to the University of KwaZulu-Natal, or directly via the respective corresponding authors. Also considered are structural elements of these alkaloids which may be used to explain such activities as well as to provide a foundation in attempts to modulate activities. In addition, evidence is provided on the molecular basis to these effects which could guide efforts in drug discovery.

Cancer is a leading cause of death worldwide. This, in spite of the tremendous gains made in cancer chemotherapies over the past several decades. The identification and development of new targets with greater structural diversities and better potencies are at the forefront of drug discovery endeavors across disciplines. Plants have afforded a significant number of successful anticancer drugs, several of which manifest their activities by inducing apoptosis (or programmed cell death) in cancer cells. The Amaryllidaceae alkaloids have similarly distinguished themselves as potent antiproliferative agents, some at the nanomolar level, with selective apoptosis inducing effects demonstrated in a wide variety of cancer cells. The proteolytic enzymes caspases are the key effectors of the apoptotic pathways, the main function of which is, in turn, the activation of caspases. Once activated caspases set in motion an intricately choreographed cascade of events leading to eventual cell death and phagocytosis. The lycorane and crinane group of alkaloids were amongst the first of the Amaryllidaceae for which apoptosis and attendant caspase inducing effects were discovered. These have been central in ongoing efforts to unravel the mechanistic basis to the cytotoxicity of these alkaloids. This review focuses on the various caspases which have been shown to be integral in apoptosis signaling pathways mediated by lycorane and crinane alkaloids.

Characteristics of buildings and land cover surrounding buildings influence the number of bird-window collisions, yet little is known about whether bird-window collisions are associated with urbanization at large spatial scales. We initiated a continent-wide study in North America to assess how bird-window collision mortality is influenced by building characteristics, landscaping around buildings, and regional urbanization. In autumn 2014, researchers at 40 sites (N = 281 buildings) used standardized protocols to document collision mortality of birds, evaluate building characteristics, and measure local land cover and regional urbanization. Overall, 324 bird carcasses were observed (range = 0–34 per site) representing 71 species. Consistent with previous studies, we found that building size had a strong positive effect on bird-window collision mortality, but the strength of the effect on mortality depended on regional urbanization. The positive relationship between collision mortality and building size was greatest at large buildings in regions of low urbanization, locally extensive lawns, and low-density structures. Collision mortality was consistently low for small buildings, regardless of large-scale urbanization. The mechanisms shaping broad-scale variation in collision mortality during seasonal migration may be related to habitat selection at a hierarchy of scales and behavioral divergence between urban and rural bird populations. These results suggest that collision prevention measures should be prioritized at large buildings in regions of low urbanization throughout North America.

Representatives of the genus Cyrtanthus including Cyrtanthus contractus of the Amaryllidaceae family are widely used in African traditional medicine for the treatment of a range of ailments, including mental illness and age-related dementia. The alkaloid constituents distributed within the genus, which are chiefly responsible for the biological activity of the derived extracts, are thought to be influenced by changes in the growing environment. Natural growing populations of C. contractus were tagged and collected every 15th day of each month over a 12 month period. The ethanol bulb extracts from each of the collected samples were evaluated for total alkaloid content, cytotoxic effects, acetylcholinesterase and cyclooxygenase inhibition as well as antimicrobial activities. Some notable bioactivities were recorded for extracts collected during certain months of the year, particularly the cytotoxic effects against human cancer cell lines and enzyme inhibition (AChE and COX). The cytotoxic effects and AChE and COX enzyme inhibitory activities of extracts collected in May and September are of considerable interest. Similarly total alkaloids varied markedly from one month to the other. The bioactivity exhibited by C. contractus bulb extracts during certain months of the year, particularly in May and September, justifies the collection and use of these bulbs for treatment of the relevant ailments in traditional medicine during these periods.

This study offers a unique contribution to the literature by investigating the influential factors of energy-related, carbon dioxide emission intensity among a panel of 30 provinces in China covering the period 1991–2010. We use novel spatial panel data models to analyze the drivers of energy-related emission intensity, which we posit are characterized by spatial dependence. Our results suggest (1) emission intensities are negatively affected by per-capita, province-level GDP and population density; (2) emission intensities are positively affected by the structure of energy consumption and the transportation sector; and, (3) energy prices have no effect on emission intensities.

The discovery of the karrikin class of plant growth regulators (PGRs) is a milestone accomplishment in plant biochemistry and physiology, with significant potential in agriculture and horticulture. These compounds have in common a fused furano-pyran ring system featuring various permutations of methyl substitution. Chief amongst these compounds is karrikinolide (KAR1), identified as the key germination stimulant present in plant-derived smoke, which together with five other closely-related structures (KAR2–KAR6) make up the karrikin class of PGRs. By contrast, the germination inhibitor 3,4,5-trimethyl-2(5H)-furanone has also been identified in plant-derived smoke. Various synthetic endeavours have been undertaken for structure–activity relationship study purposes as well as to probe the molecular mechanics of these compounds. In this study, syntheses of KAR1, KAR3 and S-KAR1 were carried out and their structures verified by X-ray crystallography. Effects on germination were measured against the inhibitor 3,4,5-trimethyl-2(5H)-furanone in Grand Rapids lettuce seeds. X-ray crystallographic data and germination promotory activity for S-KAR1 are described for the first time.

Ethnopharmacological relevance Boophone disticha is the most common member of the South African Amaryllidaceae used extensively in traditional medicine of the various indigenous population groups, including the Sotho, Xhosa and Zulu as well as the San. This survey was carried out to identify and highlight areas relevant to the traditional usage of Boophone disticha. Pharmacological aspects were examined with the purpose of reconciling these with the traditional usage of the plant. In relation to phytochemical make-up, particular attention was paid on how its alkaloid constitution might corroborate the various biological effects manifested by the plant. Materials and methods Information gathering involved the use of four different database platforms, including Google Scholar, ScienceDirect, SciFinder® and Scopus. Arrangement and detailing of this information is as reflected in the various sections of the paper. Results Sixteen categories were identified under which Boophone disticha finds use in traditional medicine. These were shown to include general usage purposes, such as ‘cultural and dietary’, ‘well-being’, ‘personal injury’, ‘divinatory purposes’, ‘psychoactive properties’ and ‘veterinary uses’. Furthermore, traditional usage was seen to involve six body systems, including functions pertaining to the circulatory, gastrointestinal, muscular, neurological, respiratory and urinary systems. The four remaining categories relate to use for inflammatory conditions, cancer, malaria and tuberculosis. Overall, three areas were discernible in which Boophone disticha finds most usage, which are (i) ailments pertaining to the CNS, (ii) wounds and infections, and (iii) inflammatory conditions. In addition, several aspects pertaining to the toxic properties of the plant are discussed, including genotoxicity, mutagenicity and neurotoxicity. Conclusion The widespread ethnic usage of Boophone disticha has justified its standing as a flagship for the Amaryllidaceae and its relevance to South African traditional medicine. Furthermore, its promising pharmacological and phytochemical profiles have stimulated significant interest in the clinical realm, especially in the areas of cancer and motor neuron disease chemotherapy. These collective properties should prove useful in steering the progress of the plant towards a wider audience.

article i nfo The "large sour plum" tree Ximenia caffra Sond. (Olacaceae) is the only African representative of the genus Ximenia L., with a distribution covering East Africa, from Tanzania in the north to South Africa, as well as parts of Botswana and Namibia. It has many uses in traditional medicine, including treatment of wounds and infections as well as diarrhea, which have been verified through various pharmacological studies. Fur- thermore, the plant is also known for its nutritional and cosmetic value. Its edible fruits are known to be high in protein, potassium and vitamin C, while the seed oil, also referred to as "Ximenia oil" is rich in long chain unsaturated fatty acids and finds use as a domestic biofuel, with characteristics amenable to cosmetic development as topical applicants. Extracts of the plants are also widely used for treating sexually transmit- ted infections (STIs), which has been verified through ethnobotanical surveys and pharmacological screens. Based on these observations, X. caffra var. caffra was examined for its phytochemical composition and activity against the gonorrheal pathogen Neisseria gonorrhoeae. Initially, the leaf ethanolic extract was seen to be ac- tive (43.9% inhibition). The DCM partition of this extract (with 78.8% inhibition) was subjected to bioassay guided fractionation leading to the identification of the bisnorsesquiterpene vomifoliol which exhibited sig- nificant activity (63.1%) against N. gonorrhoeae.

China is one of the world’s most rapidly growing countries and the largest consumer of energy in the world. As a result, China’s pollution emissions almost doubled from 2002 to 2007, and in 2006 it surpassed the United States to become the world’s top carbon dioxide emitter. Understanding the sources of emissions is essential towards designing policies aimed at curbing carbon emissions in China. The surge in China’s exports has been partially blamed for this increase in emissions. To understand the sources of emissions, this study uses a vector autoregression model to examine the relationship among exports, CO2 emissions, coal consumption and trade openness in China for the years 1970–2010. The study uses a modified version of Granger Causality developed by Toda and Yamamoto [56]. The main findings within the study indicate: (1) Granger Causality running from exports to emissions; (2) Granger Causality running from coal consumption to exports; and (3) GDP determines future variability in exports and CO2 emissions. Results suggest that governmental policies aimed at controlling coal consumption could affect CO2 emissions and exports. Results from this study should assist in formulating policies to mitigate both CO2 emissions and coal consumption.

Several of the Amaryllidaceae alkaloids are known for their cytotoxic properties, of which the lycorine group representatives are prominent for potent and cell line specific antiproliferative activities. As a distinct niche within the lycorine group, the phenanthridones, exemplified by narciclasine and pancratistatin, have shown much promise as remarkably selective cytotoxic agents and are presently at various stages of development, with a clinical candidate likely to appear on the market within the next decade. The crinane group of the Amaryllidaceae has also spawned several molecules, such as crinamine and haemanthamine, with promising cytotoxic activities. In the present study, the β-crinane distichamine as well as the phenanthridone narciprimine, both rare constituents of the Amaryllidaceae, are revealed as novel antiproliferative agents. Apoptosis-inducing effects are demonstrated for distichamine in human acute lymphoblastic leukemia (CEM) cells. These findings provide further insights to the structural details of the apoptosis-inducing pharmacophores resident within both series of alkaloids.

Cycads are a group of slow-growing, perennial, dioecious plants which in geological times thrived during the Mesozoic era. The present worldwide complement of around 300 species is distributed through both tropical and subtropical regions of the globe, and has pronounced centres in Australia, Mexico and South Africa. These popular plants are known for their ornamental, economic, dietary and medicinal value. However, increased demand collectively from this sector, as well as decimation of large tracts of cycad populations in the wild through habitat destruction and unscrupulous collection, has precipitated a fragile conservation status for the family, with majority of its species listed as threatened by statutory bodies such as CITES and IUCN. Despite their popularity, cycads have for several centuries been known to be toxic. The plants have been shown to have carcinogenic, mutagenic, teratogenic and neurotoxic properties, and its major constituent principles macrozamin and cycasin have exhibited similar effects in model studies. Cycads are used widely in traditional medicine (TM) in South Africa and the majority of endemic species are commonly traded on local TM markets. The present study deals with the isolation of macrozamin from seed kernels of Encephalartos transvenosus and quantification of this toxic methylazoxymethanol (MAM) glycoside via HPLC in selected indigenous species.

Ethnopharmacological relevance Boophone disticha (Amaryllidaceae) is one of the most common bulbous plants used for medicinal purposes by the indigenous people of southern Africa. Its use as a narcotic substance by the Khoi/San tribes has been known for several centuries, while the Sotho, Xhosa and Zulu people are known to use the plant to treat a host of ailments, including inflammation, wounds, gynaecological conditions and psychosis. Aim of the study Much of the pharmacological work on the plant, such as affinity to the serotonin transporter, has been based on its reputed usage for narcotic purposes. However, its widespread use to treat wounds and infections has not been linked to a specific chemical entity. In this regard, Boophone disticha was here examined for its phytochemical composition which could shed light on the use of the plant for such purposes. Materials and methods The known crinane alkaloids buphanidrine and distichamine were isolated via column chromatography of the ethanolic extract of bulbs of Boophone disticha. Structural details of the compounds were determined by high field 2D NMR and mass spectroscopic techniques. Microbial activity against selected Gram-positive and Gram-negative bacteria was ascertained according to the micro-dilution assay. Results Both buphanidrine and distichamine were uncovered as novel, broad spectrum moderately active, antibacterial agents with the best MIC value detected at 0.063 mg/ml for Staphylococcus aureus, Escherichia coli and Klebsiella pneumoniae. MIC values for Bacillus subtilis were two-fold less than that observed for the other three bacteria, suggesting that the extract and pure compounds were selective in their interaction with the bacterial pathogens. Conclusion Phytochemical investigation of Boophone disticha has led to the identification of two known crinanes, buphanidrine and distichamine. Based on the reputed traditional use of the plant for wounds and infections, both compounds were screened for antibacterial activity which revealed them to be novel, broad spectrum antibacterial agents with the best MIC value set at 0.063 mg/ml. Their close structural similarity may have bearing on their similar activity profiles.

Ensuring interoperability between WebGIS applications is essential for maximizing access to data, data sharing, and data manipulation. Interoperability is maximized through the adoption of best practices, use of open standards, and utilization of spatial data infrastructure (SDI). While many of the interoperability challenges like infrastructure, data exchange, and file formats are common between applications, some regions like the Arctic present specific challenges including the need for presenting data in one or more polar projections. This paper describes the Arctic Research Mapping Application (ARMAP) suite of online interactive maps, web services, and virtual globes (the ARMAP suite; http://armap.org/) and several of the interoperability challenges and solutions encountered in development to date. ARMAP is a unique science and logistic tool supporting United States and international Arctic science by providing users with the ability to access, query, and browse information and data. Access to data services include a text-based search utility, an Internet Map Server client (ArcIMS), a lightweight Flex client, ArcGIS Explorer and Google Earth virtual globes, and Open Geospatial Consortium (OGC) compliant web services, such as Web Map Service (WMS) and Web Feature Service (WFS). Through the ARMAP suite, users can view a variety of Arctic map layers and explore pertinent information about United States Arctic research efforts. The Arctic Research Logistics Support Service (ARLSS) database is the informational underpinning of ARMAP. Avoiding duplication of effort has been a key priority in the development of the ARMAP applications. The ARMAP suite incorporates best practices that facilitate interoperability such as Federal Geographic Data Committee (FGDC) metadata standards, web services for embedding external data and serving framework layers, and open standards such as Open Geospatial Consortium (OGC) compliant web services. Many of the features and capabilities of ARMAP are expected to greatly enhance the development of an Arctic SDI.

Ethnopharmacological relevance Plants of the family Amaryllidaceae are used widely in traditional medicine in South Africa. Several of these, including representatives of the genus Cyrtanthus find use in the treatment of mental illness and age-related dementia. Aim of the study Based on the distribution of central nervous system-activating alkaloidal constituents within the genus Cyrtanthus , Cyrtanthus contractus was here explored for such compounds which could interact with acetylcholinesterase (AChE), of significance in the progression of neurodegeneration associated with Alzheimer's disease. Materials and methods The known phenanthridone alkaloid narciprimine was isolated via column chromatography of the ethanolic extract of bulbs of Cyrtanthus contractus . The structure of the compound was determined by high field 2D NMR and mass spectroscopic techniques. The classical method of Ellman et al. was used in the determination of AChE inhibitory activity. Results The isolation of narciprimine from Cyrtanthus contractus is a landmark find since it has previously only been identified in Zephyranthes , Narcissus and Lycoris , genera endemic to the Americas, Europe and Asia, respectively. Narciprimine exhibited micromolar inhibitory activity (IC 50 78.9) against the enzyme acetylcholinesterase. Conclusion This work represents the first isolation of narciprimine from an African Amaryllidaceae species, which may be of chemotaxonomic significance. The AChE inhibitory activity of narciprimine, taken together with activities of other structurally similar inhibitors within the series affords further insight to the structural details of the lycorine alkaloid acetylcholinesterase inhibitory pharmacophore.

Most water management studies concentrate on the inter-temporal allocation problem or, more recently, spatial dynamics – but not both. While early spatial–temporal studies focused on the allocation of water quantity, this paper presents an approach to water quality analysis that incorporates both spatial and temporal dynamics in a watershed framework. The acid mine drainage (AMD) problem in the Cheat River watershed of West Virginia, USA, serves as a case study and provides an opportunity to test the modeling approach developed. The empirical models are written in General Algebraic Modeling System (GAMS) and solved using the CPLEX mixed integer programming package. The results suggest that available investments should be concentrated in heavily impaired stream segments. The model can be used to assess the economic implications of alternative watershed Total Maximum Daily Load (TMDL) implementation or other management strategies.

The synthesis of differentially functionalized analogs of the Amaryllidaceae alkaloid lycorine, accessed via a concise chemoselective silylation strategy, is described uncovering two of the most potent inhibitors of acetylcholinesterase (AChE) identified to date in this series. Important elements of this novel pharmacophore were elucidated through structure-activity relationship (SAR) studies.

The watershed characterization and modeling system (WCMS) was developed to support decision making and the management of water resources at a statewide level in West Virginia. Specific hydrological analysis functions were combined within a customized GIS interface to provide decision support capabilities to both technical and non-technical users. Components of the current system include: an overland flow path model that indicates optimum water quality sampling locations, flow estimation for all streams in an identified area, an instream water quality and loading model for pollutant levels, and a ranking model to prioritize treatment alternatives based on user defined criteria and preferences. The primary goals of this system are to provide consistent technical information related to natural watershed processes and to predict the impacts of alternative management scenarios for decision makers. WCMS is currently used by the West Virginia Department of Environmental Protection (WVDEP) to guide policy development and management decisions that address watershed and water quality issues throughout the state.

seco-Derivatives of the anticancer agent pancratistatin bearing the 2S,3S,4S,5S configuration were accessed via a novel, highly diastereoselective anti-aldol reaction. Structure–activity relationships reveal important insights into the seco-pancratistatin pharmacophore as a potent and selective inhibitor of human cytochrome P450 3A4 (CYP3A4), and highlight features of concern in advancing a potent, selective anticancer agent in the pancratistatin series.

The relationship between primary and scrap prices has been hypothesized for the most part as unidirectional, characterized by spillovers from primary to scrap prices. The purpose of this study is to evaluate empirically the dynamic interactions between primary and scrap metal prices through multivariate time series methods. In addition, the study expands the investigation at the level of volatility transmission, which has not been previously examined. The metal prices utilized are for copper, lead, and zinc for the period 1984–2001. The paper demonstrates differing long run and short run links. Scrap prices do not improve the long run interpretation of primary prices, but information flows from the scrap to the primary markets exist in the short run. Additionally, the copper and lead markets exhibit bidirectional information flows in terms of volatility transmission. The analysis provides valuable insight into the interactions of the primary and scrap metal sectors which can be used to improve forecasting and planning.