931 resultados para O57 - Comparative Studies of Countries
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The relationship between reef corals and endosymbiotic dinoflagellates is fundamental to the existence of coral reefs. To evaluate the fidelity of coral-Symbiodinium mutualisms, corals maintained in aquaria for years were analyzed by denaturant gradient gel electrophoresis (DGGE). Comparing Symbiodinium populations of captive aquarium colonies with known associations in nature is a practical way of examining partner flexibility. The finding of "normal" symbiont populations in corals existing under highly variable conditions supports the premise that most coral colonies possess stable associations. High sensitivity real-time PCR (rtPCR) was used to evaluate background populations of the putatively stress-tolerant Symbiodinium D in reef corals of the Caribbean. Analyses of samples collected during periods of environmental stability indicate the ability of Symbiodinium D to associate with a wider diversity of host taxa than previously recognized. To gain a broader perspective with regard to the ecology of Symbiodinium D1a, rtPCR and DGGE were used to evaluate the symbiont populations of reef corals from Barbados before and after the 2005 mass coral bleaching. Background populations were observed in 56% of the host genera prior to observations of bleaching. These findings indicate that 'stress', not 'bleaching', caused the displacement of 'natural' symbiont population and the opportunistic proliferation of D1a in many host taxa. Of the 12 host taxa monitored before and after the bleaching event, there was a 40% increase in colonies hosting Symbiodinium D1a. Together, these studies elucidate the mechanism responsible for recent observations reporting the emergence of Symbiodinium D following thermal disturbances. These observations are now most easily explained as the disproportionate growth of existing in hospite symbiont populations, rather than novel symbiont acquisition subsequent to bleaching. To evaluate the comparative "fitness" of corals able to host multiple symbiont types, rates of calcification were measured in P. verrucosa hosting either Symbiodinium C1b-c or D1 at elevated temperature. Rates of calcification decreased significantly for both host-symbiont combinations, but differences attributable to symbiont composition were not detected. This research improves our knowledge of the symbiosis biology and ecology of reef corals and contributes information necessary to most accurately predict the response of these ecosystems to global climate changes.
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This study explained the diversity of corporate financial practices in two nations. Existing studies have emphasized the reliance on equity finance in U.S. firms and bank loans in Japanese firms. In fact, patterns of corporate finance were much more complex. Financial institutions, which were created by national economic policy and regulation, affected corporate financial practices, but corporate financial practices often differed from what policymakers expected. Differences in corporate financial practices between nations also reflected differences in the mixture of industries in each nation. Many factors such as the amount of fixed capital, the process of production, the level of risk, the degree of innovation, and the importance of the industry in the national economy affected corporate financial practices. In addition, corporate financial practices within each nation differed from firm to firm due to managers’ considerations about stock ownership, which would affect their control power; corporate finance was closely related to control over management through ownership. To explain these complexities of corporate financial practices, the study linked corporate finance with the development of financial institutions in the United States and in Japan. While financial institutions affected corporate financial practices, the response of the firms to financial institutions and opportunities were diverse. The study also attempted to grasp variations in corporate financial practices by dealing with companies in three sectors: railroads, public utilities, and manufacturing. Finally, the study examined the structure of firm ownership. Contradictory to the widely held belief that U.S. firms distributed securities more widely to the public than did Japanese firms, many large American firms remained closely held, while some Japanese counterparts built publicly-held corporations.
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A difficult transition to a new paradigm of Democratic Security and the subsequent process of military restructuring during the nineties led El Salvador, Honduras, Guatemala and Nicaragua to re-consider their old structures and functions of their armed forces and police agencies. This study compares the institutions in the four countries mentioned above to assess their current condition and response capacity in view of the contemporary security challenges in Central America. This report reveals that the original intention of limiting armies to defend and protect borders has been threatened by the increasing participation of armies in public security. While the strength of armies has been consolidated in terms of numbers, air and naval forces have failed to become strengthened or sufficiently developed to effectively combat organized crime and drug trafficking and are barely able to conduct air and sea operations. Honduras has been the only country that has maintained a proportional distribution of its armed forces. However, security has been in the hands of a Judicial Police, supervised by the Public Ministry. The Honduran Judicial Police has been limited to exercising preventive police duties, prohibited from carrying out criminal investigations. Nicaragua, meanwhile, possesses a successful police force, socially recognized for maintaining satisfactory levels of security surpassing the Guatemalan and El Salvadoran police, which have not achieved similar results despite of having set up a civilian police force separate from the military. El Salvador meanwhile, has excelled in promoting a Police Academy and career professional education, even while not having military attachés in other countries. Regarding budgetary issues, the four countries allocate almost twice the amount of funding on their security budgets in comparison to what is allocated to their defense budgets. However, spending in both areas is low when taking into account each country's GDP as well as their high crime rates. Regional security challenges must be accompanied by a professionalization of the regional armies focused on protecting and defending borders. Therefore, strong institutional frameworks to support the fight against crime and drug trafficking are required. It will require the strengthening of customs, greater control of illicit arms trafficking, investment in education initiatives, creating employment opportunities and facilitating significant improvements in the judicial system, as well as its accessibility to the average citizen.
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The purpose of this study was to delineate which demographic and school variables were important for predicting the achievement of 10th grade African-American students. The sample population was divided into two groups: high-achievers, students with GPAs of 3.5 or higher, and low-achievers, students with GPAs of 1.5 or lower. Variables examined in the study included: gender; birth place; student's native language; exceptionality (ESE); history of English proficiency (LEP); SES (lunch status) in elementary and high school; the percentage of the Black student population in high school; and suspensions, absences, tardies, and the Stanford Achievement Test (SAT) scores in reading comprehension, mathematics computation, and mathematics applications in elementary and middle school. Two separate logistic regression analyses were conducted to determine which variables were influential in predicting achievement.^ Analysis 1 (N = 366), which included all the variables, except the SAT percentile scores, correctly classified 87% of the students as high-achievers or low-achievers. The results from Analysis 1 revealed that students who--were female; spoke a language other than English as their first language; did not apply for free or reduced lunch in elementary school; were in the gifted program; had no absences or tardies in elementary school; had no suspensions or tardies in middle school; and attended a high school with a lower percentage of Black students--were more likely to be high-achieving than low-achieving.^ Analysis 2 (N = 274) included all the variables and resulted in 94% of the students being correctly classified. It was found that students who--were female; were currently or previously classified as Limited English Proficient (LEP); did not apply for free or reduced lunch in elementary school; had no suspensions or tardies in middle school; and had higher percentile scores in reading comprehension and mathematics computation on the SAT in middle school--were more likely to high-achieving than low-achieving.^ The quantitative analyses were coupled with interviews from a purposeful sample of the population (N = 12) to gain additional insight about why some African-American students are succeeding in our schools and others are not. This study provides a viable means for assessing African-American students' achievement patterns in our schools. ^
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This study explained the diversity of corporate financial practices in two nations. Existing studies have emphasized the reliance on equity finance in U.S. firms and bank loans in Japanese firms. In fact, patterns of corporate finance were much more complex. Financial institutions, which were created by national economic policy and regulation, affected corporate financial practices, but corporate financial practices often differed from what policymakers expected. Differences in corporate financial practices between nations also reflected differences in the mixture of industries in each nation. Many factors such as the amount of fixed capital, the process of production, the level of risk, the degree of innovation, and the importance of the industry in the national economy affected corporate financial practices. In addition, corporate financial practices within each nation differed from firm to firm due to managers’ considerations about stock ownership, which would affect their control power; corporate finance was closely related to control over management through ownership. To explain these complexities of corporate financial practices, the study linked corporate finance with the development of financial institutions in the United States and in Japan. While financial institutions affected corporate financial practices, the response of the firms to financial institutions and opportunities were diverse. The study also attempted to grasp variations in corporate financial practices by dealing with companies in three sectors: railroads, public utilities, and manufacturing. Finally, the study examined the structure of firm ownership. Contradictory to the widely held belief that U.S. firms distributed securities more widely to the public than did Japanese firms, many large American firms remained closely held, while some Japanese counterparts built publicly-held corporations.
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This research project involves a comparative, cross-national study of truth and reconciliation commissions (TRCs) in countries around the world that have used these extra-judicial institutions to pursue justice and promote national reconciliation during periods of democratic transition or following a civil conflict marked by intense violence and severe human rights abuses. An important objective of truth and reconciliation commissions involves instituting measures to address serious human rights abuses that have occurred as a result of discrimination, ethnocentrism and racism. In recent years, rather than solely utilizing traditional methods of conflict resolution and criminal prosecution, transitional governments have established truth and reconciliation commissions as part of efforts to foster psychological, social and political healing.
The primary objective of this research project is to determine why there has been a proliferation of truth and reconciliation commissions around the world in recent decades, and assess whether the perceived effectiveness of these commissions is real and substantial. In this work, using a multi-method approach that involves quantitative and qualitative analysis, I consider the institutional design and structural composition of truth and reconciliation commissions, as well as the roles that these commissions play in the democratic transformation of nations with a history of civil conflict and human rights violations.
In addition to a focus on institutional design of truth and reconciliation commissions, I use a group identity framework that is grounded in social identity theory to examine the historical background and sociopolitical context in which truth commissions have been adopted in countries around the world. This group identity framework serves as an invaluable lens through which questions related to truth and reconciliation commissions and other transitional justice mechanisms can be explored. I also present a unique theoretical framework, the reconciliatory democratization paradigm, that is especially useful for examining the complex interactions between the various political elements that directly affect the processes of democratic consolidation and reconciliation in countries in which truth and reconciliation commissions have been established. Finally, I tackle the question of whether successor regimes that institute truth and reconciliation commissions can effectively address the human rights violations that occurred in the past, and prevent the recurrence of these abuses.
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In the last two decades, the field of homogeneous gold catalysis has been
extremely active, growing at a rapid pace. Another rapidly-growing field—that of
computational chemistry—has often been applied to the investigation of various gold-
catalyzed reaction mechanisms. Unfortunately, a number of recent mechanistic studies
have utilized computational methods that have been shown to be inappropriate and
inaccurate in their description of gold chemistry. This work presents an overview of
available computational methods with a focus on the approximations and limitations
inherent in each, and offers a review of experimentally-characterized gold(I) complexes
and proposed mechanisms as compared with their computationally-modeled
counterparts. No aim is made to identify a “recommended” computational method for
investigations of gold catalysis; rather, discrepancies between experimentally and
computationally obtained values are highlighted, and the systematic errors between
different computational methods are discussed.
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Background: There is growing evidence that individual EEG differences may aid in classifying patients with major depressive disorder (MDD) and also help predict clinical response to antidepressant treatment. This study aims to compare the effectiveness of EEG frequency band power, alpha asymmetry and prefrontal theta cordance towards escitalopram response prediction and MDD diagnosis, in a multi-site initiative. Methods: Resting EEG (eyes open and closed) was recorded from 64 electrodes in 44 depressed patients and 20 healthy controls at baseline, 2 weeks post-treatment and 8 weeks post-treatment. Clinical response was measured as change from baseline MADRS of 50% or more. EEG measures were analyzed (1) at baseline (2) at 2 weeks post-treatment and (3) as an ‘‘early change” variable defined as change in EEG from baseline to 2 weeks post-treatment. Results: At baseline, responders exhibited greater absolute alpha power in the left hemisphere versus the right while non-responders showed the opposite. Responders further exhibited a cortical asymmetry of greater right relative to left activity in parietal areas. Groups also differed in baseline relative delta power with responders showing greater power in the right hemisphere versus the left while non-responders showed the opposite. At 2 weeks post-treatment, responders exhibited greater absolute beta power in the left hemisphere relative to right and the opposite was noted for non-responders. The opposite pattern was noted for absolute and relative delta power at 2 weeks post-treatment. Responders exhibited early reduction in relative alpha power and early increments in relative theta power. Non-responders showed a significant early increase in prefrontal theta cordance. Absolute delta power helped distinguish MDD patients from healthy controls. Conclusions: Hemispheric asymmetries in the alpha and delta bands at pre-treatment baseline and at 2 weeks post-treatment have moderate to moderately strong predictive utility towards antidepressant treatment response. These findings have significant potential for improving clinical practice in psychiatry by eventually guiding clinical choice of treatments. This would greatly benefit patients awaiting relief from depressive symptoms as treatment optimization would help overcome problems associated with delayed recovery. Our results also indicate that resting EEG activity may have clinical utility in predicting MDD diagnosis.
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Knight M, Acosta C, Brocklehurst P, Cheshire A, Fitzpatrick K, Hinton L, Jokinen M, Kemp B, Kurinczuk JJ, Lewis G, Lindquist A, Locock L, Nair M, Patel N, Quigley M, Ridge D, Rivero-Arias O, Sellers S, Shah A on behalf of the UKNeS coapplicant group. Background Studies of maternal mortality have been shown to result in important improvements to women’s health. It is now recognised that in countries such as the UK, where maternal deaths are rare, the study of near-miss severe maternal morbidity provides additional information to aid disease prevention, treatment and service provision. Objectives To (1) estimate the incidence of specific near-miss morbidities; (2) assess the contribution of existing risk factors to incidence; (3) describe different interventions and their impact on outcomes and costs; (4) identify any groups in which outcomes differ; (5) investigate factors associated with maternal death; (6) compare an external confidential enquiry or a local review approach for investigating quality of care for affected women; and (7) assess the longer-term impacts. Methods Mixed quantitative and qualitative methods including primary national observational studies, database analyses, surveys and case studies overseen by a user advisory group. Setting Maternity units in all four countries of the UK. Participants Women with near-miss maternal morbidities, their partners and comparison women without severe morbidity. Main outcome measures The incidence, risk factors, management and outcomes of uterine rupture, placenta accreta, haemolysis, elevated liver enzymes and low platelets (HELLP) syndrome, severe sepsis, amniotic fluid embolism and pregnancy at advanced maternal age (≥ 48 years at completion of pregnancy); factors associated with progression from severe morbidity to death; associations between severe maternal morbidity and ethnicity and socioeconomic status; lessons for care identified by local and external review; economic evaluation of interventions for management of postpartum haemorrhage (PPH); women’s experiences of near-miss maternal morbidity; long-term outcomes; and models of maternity care commissioned through experience-led and standard approaches. Results Women and their partners reported long-term impacts of near-miss maternal morbidities on their physical and mental health. Older maternal age and caesarean delivery are associated with severe maternal morbidity in both current and future pregnancies. Antibiotic prescription for pregnant or postpartum women with suspected infection does not necessarily prevent progression to severe sepsis, which may be rapidly progressive. Delay in delivery, of up to 48 hours, may be safely undertaken in women with HELLP syndrome in whom there is no fetal compromise. Uterine compression sutures are a cost-effective second-line therapy for PPH. Medical comorbidities are associated with a fivefold increase in the odds of maternal death from direct pregnancy complications. External reviews identified more specific clinical messages for care than local reviews. Experience-led commissioning may be used as a way to commission maternity services. Limitations This programme used observational studies, some with limited sample size, and the possibility of uncontrolled confounding cannot be excluded. Conclusions Implementation of the findings of this research could prevent both future severe pregnancy complications as well as improving the outcome of pregnancy for women. One of the clearest findings relates to the population of women with other medical and mental health problems in pregnancy and their risk of severe morbidity. Further research into models of pre-pregnancy, pregnancy and postnatal care is clearly needed.
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Increasing research has highlighted the effects of changing climates on the occurrence and prevalence of toxigenic Aspergillus species producing aflatoxins. There is concern of the toxicological effects to human health and animal productivity following acute and chronic exposure that may affect the future ability to provide safe and sufficient food globally. Considerable research has focused on the detection of these toxins, based on the physicochemical and biochemical properties of the aflatoxin compounds, in agricultural products for human and animal consumption. As improvements in food security continue more regulations for acceptable levels of aflatoxins have arisen globally; the most stringent in Europe. These regulations are important for developing countries as aflatoxin occurrence is high significantly effecting international trade and the economy. In developed countries analytical approaches have become highly sophisticated, capable of attaining results with high precision and accuracy, suitable for regulatory laboratories. Regrettably, many countries that are affected by aflatoxin contamination do not have resources for high tech HPLC and MS instrumentation and require more affordable, yet robust equally accurate alternatives that may be used by producers, processors and traders in emerging economies. It is especially important that those companies wishing to exploit the opportunities offered by lucrative but highly regulated markets in the developed world, have access to analytical methods that will ensure that their exports meet their customers quality and safety requirements.
This work evaluates the ToxiMet system as an alternative approach to UPLC–MS/MS for the detection and determination of aflatoxins relative to current European regulatory standards. Four commodities: rice grain, maize cracked and flour, peanut paste and dried distillers grains were analysed for natural aflatoxin contamination. For B1 and total aflatoxins determination the qualitative correlation, above or below the regulatory limit, was good for all commodities with the exception of the dried distillers grain samples for B1 for which no calibration existed. For B1 the quantitative R2 correlations were 0.92, 0.92, 0.88 (<250 μg/kg) and 0.7 for rice, maize, peanuts and dried distillers grain samples respectively whereas for total aflatoxins the quantitative correlation was 0.92, 0.94, 0.88 and 0.91. The ToxiMet system could be used as an alternative for aflatoxin analysis for current legislation but some consideration should be given to aflatoxin M1 regulatory levels for these commodities considering the high levels detected in this study especially for maize and peanuts
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Localisation is the process of taking a product and adapting it to fit the culture in question. This usually involves making it both linguistically and culturally appropriate for the target audience. While there are many areas in video game translations where localisation holds a factor, this study will focus on localisation changes in the personalities of fictional characters between the original Japanese version and the English localised version of the video game Final Fantasy XIV: A Realm Reborn and its expansion Heavensward for PC, PS3 and PS4. With this in mind, specific examples are examined using Satoshi Kinsui's work on yakuwarigo, role language as the main framework for this study. Five non-playable characters were profiled and had each of their dialogues transcribed for a comparative analysis. This included the original Japanese text, the officially localised English text and a translation of the original Japanese text done by myself. Each character were also given a short summary and a reasoned speculation on why these localisation changes might have occurred. The result shows that there were instances where some translations had been deliberately adjusted to ensure that the content did not cause any problematic issues to players overseas. This could be reasoned out that some of the Japanese role languages displayed by characters in this game could potentially cause dispute among the western audience. In conclusion, the study shows that localisation can be a difficult process that not only requires a translator's knowledge of the source and target language, but also display some creativity in writing ability to ensure that players will have a comparable experience without causing a rift in the fanbase.
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[EN] Background: Plasma biochemical and hematologic variables are important in the management of endangered sea turtles, such as loggerheads. However, studies on blood biochemistry and hematology of loggerheads are limited, and different concentrations according to variable criteria have been reported. Objective: The purpose of this study was to establish and compare baseline plasma chemistry and hematology values in Eastern Atlantic juvenile and adult nesting loggerhead sea turtles (Caretta caretta).
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International audience
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The forensic toxicologist faces challenges in the detection of drugs and poisons in biological samples due to transformations which occur both during life and after death. For example, changes can result from drug metabolism during life or from the use of formalin solution for post mortem embalming purposes. The former requires the identification of drug metabolites and the latter the identification of chemical reaction products in order to know which substances had been administered. The work described in this thesis was aimed at providing ways of tackling these challenges and was divided into two parts. Part 1 investigated the use of in vitro drug metabolism by human liver microsomes (HLM) to obtain information on drug metabolites and Part 2 investigated the chemical reactions of drugs and a carbamate pesticide with formalin solution and formalin-blood. The initial aim of part I was to develop an in vitro metabolism method using HLM, based on a literature review of previous studies of this type. MDMA was chosen as a model compound to develop the HLM method because its metabolism was known and standards of its metabolites were commercially available. In addition, a sensitive and selective method was developed for the identification and quantitation of hydrophilic phase I drug metabolites using LC/MS/MS with a conventional reverse-phase (C18) column. In order to obtain suitable retention factors for polar drug metabolites on this column, acetyl derivatives were evaluated for converting the metabolites to more lipophilic compounds and an optimal separation system was developed. Acetate derivatives were found to be stable in the HPLC mobile phase and to provide good chromatographic separation of the target analytes. In vitro metabolism of MDMA and, subsequently, of other drugs involved incubation of 4 µg drug substance in pH 7.4 buffer with an NADPH generating system (NGS) at 37oC for 90 min with addition of more NGS after 30 min. The reaction was stopped at 90 min by the addition of acetonitrile before extraction of the metabolites. Acetate derivatives of MDMA metabolites were identified by LC/MS/MS using multiple reaction monitoring (MRM). Three phase I metabolites (both major and minor metabolites) of MDMA were detected in HLM samples. 3,4-dihydroxy-methamphetamine and 4-hydroxy-3-methoxymethamphetamine were found to be major metabolites of MDMA whereas 3,4-methylenedioxyamphetamine was found to be a minor metabolite. Subsequently, ten MDMA positive urines were analysed to compare the metabolite patterns with those produced by HLM. An LC/MS method for MDMA and its metabolites in urine samples was developed and validated. The method demonstrated good linearity, accuracy and precision and insignificant matrix effects, with limits of quantitation of 0.025 µg/ml. Moreover, derivatives of MDMA and its metabolites were quantified in all 10 positive human urine samples. The urine metabolite pattern was found to be similar to that from HLM. The second aim of Part 1 was to use the HLM system to study the metabolism of some new psychoactive substances, whose misuse worldwide has necessitated the development of analytical methods for these drugs in biological specimens. Methylone and butylone were selected as representative cathinones and para-methoxyamphetamine (PMA) was chosen as a representative ring-substituted amphetamine, because of the involvement of these drugs in recent drug-related deaths, because of a relative lack of information on their metabolism, and because reference standards of their metabolites were not commercially available. An LC/MS/MS method for the analysis of methylone, butylone, PMA and their metabolites was developed. Three phase I metabolites of methylone and butylone were detected in HLM samples. Ketone reduction to β-OH metabolites and demethylenation to dihydroxy-metabolites were found to be major phase I metabolic pathways of butylone and methylone whereas N-demethylation to nor-methylone and nor-butylone were found to be minor pathways. Also, demethylation to para-hydroxyamphetamine was found to be a major phase I metabolic pathway of PMA whereas β-hydroxylation to β-OH-PMA was found to be a minor pathway. Formaldehyde is used for embalming, to reduce decomposition and preserve cadavers, especially in tropical countries such as Thailand. Drugs present in the body can be exposed to formaldehyde resulting in decreasing concentrations of the original compounds and production of new substances. The aim of part II of the study was to evaluate the in vitro reactions of formaldehyde with selected drug groups including amphetamines (amphetamine, methamphetamine and MDMA), benzodiazepines (alprazolam and diazepam), opiates (morphine, hydromorphone, codeine and hydrocodone) and with a carbamate insecticide (carbosulfan). The study would identify degradation products to serve as markers for the parent compounds when these were no longer detectable. Drugs standards were spiked in 10% formalin solution and 10% formalin blood. Water and whole blood without formalin were used for controls. Samples were analysed by LC/MS/MS at different times from the start, over periods of up to 30 days. Amphetamine, methamphetamine and MDMA were found to rapidly convert to methamphetamine, DMA and MDDMA respectively, in both formalin solution and formalin blood, confirming the Eschweiler-Clarke reaction between amine-containing compounds and formaldehyde. Alprazolam was found to be unstable whereas diazepam was found to be stable in both formalin solution and water. Both were found to hydrolyse in formalin solution and to give open-ring alprazolam and open-ring diazepam. Other alprazolam conversion products attached to paraformaldehyde were detected in both formalin solution and formalin blood. Morphine and codeine were found to be more stable than hydromorphone and hydrocodone in formalin solution. Conversion products of hydromorphone and hydrocodone attached to paraformaldehyde were tentatively identified in formalin solution. Moreover, hydrocodone and hydromorphone rapidly decreased within 24 h in formalin blood and could not be detected after 7 days. Carbosulfan was found to be unstable in formalin solution and was rapidly hydrolysed within 24 h, whereas in water it was stable up to 48 h. Carbofuran was the major degradation product, plus smaller amounts of other products, 3-ketocarbofuran and 3-hydrocarbofuran. By contrast, carbosulfan slowly hydrolysed in formalin-blood and was still detected after 15 days. It was concluded that HLM provide a useful tool for human drug metabolism studies when ethical considerations preclude their controlled administration to humans. The use of chemical derivatisation for hydrophilic compounds such as polar drug metabolites for analysis by LC/MS/MS with a conventional C18 column is effective and inexpensive, and suitable for routine use in the identification and quantitation of drugs and their metabolites. The detection of parent drugs and their metabolites or conversion and decomposition products is potentially very useful for the interpretation of cases in forensic toxicology, especially when the original compounds cannot be observed.