Search-based Automatic Repair for Fairness and Accuracy in Decision-making Software.

Decision-making software mainly based on Machine Learning (ML) may contain fairness issues (e.g., providing favourable treatment to certain people rather than others based on sensitive attributes such as gender or race). Various mitigation methods have been proposed to automatically repair fairness issues to achieve fairer ML software and help software engineers to create responsible software. However, existing bias mitigation methods trade accuracy for fairness (i.e., trade a reduction in accuracy for better fairness). In this paper, we present a novel search-based method for repairing ML-based decision making software to simultaneously increase both its fairness and accuracy. As far as we know, this is the first bias mitigation approach based on multi-objective search that aims to repair fairness issues without trading accuracy for binary classification methods. We apply our approach to two widely studied ML models in the software fairness literature (i.e., Logistic Regression and Decision Trees), and compare it with seven publicly available state-of-the-art bias mitigation methods by using three different fairness measurements. The results show that our approach successfully increases both accuracy and fairness for 61% of the cases studied, while the state-of-the-art always decrease accuracy when attempting to reduce bias. With our proposed approach, software engineers that previously were concerned with accuracy losses when considering fairness, are now enabled to improve the fairness of binary classification models without sacrificing accuracy.

Omega-3 long chain polyunsaturated fatty acids as a potential treatment for reducing dysmenorrhoea pain: Systematic literature review and meta-analysis.

AIM: This systematic literature review with meta-analysis aimed to determine the effect of omega-3 long chain polyunsaturated fatty acids on prostaglandin levels and pain severity in women with dysmenorrhoea and identify adverse side effects. METHODS: A literature search was conducted in Embase, Scopus, Web of Science, MEDLINE complete, CINAHL and AMED databases (PROSPERO CRD42022340371). Included studies provided omega-3 long chain polyunsaturated fatty acids compared to a control in women with dysmenorrhoea and reported pain and/or prostaglandin levels. A random effects meta-analysis with Cohen's d effect size (95% confidence interval) was performed in SPPS for studies that reported pain outcomes. Study quality was assessed using the Academy of Nutrition and Dietetics Quality Criteria Checklist. RESULTS: Twelve studies (n = 881 dysmenorrhoeal women) of predominantly neutral quality (83%) were included that provided daily supplementation of 300-1800 mg omega-3 long chain polyunsaturated fatty acids over 2 or 3 months. Meta-analysis (n = 8 studies) showed a large effect of omega-3 long chain polyunsaturated fatty acids (d = -1.020, 95% confidence interval -1.53 to -0.51) at reducing dysmenorrhoea pain. No studies measured prostaglandin levels, 86% of studies measuring analgesic use showed a reduction with omega-3 long chain polyunsaturated fatty acids and few studies reported mild adverse side effects in individual participants. CONCLUSIONS: Findings suggest that daily supplementation of 300-1800 mg omega-3 long chain polyunsaturated fatty acids over 2-3 months are generally well tolerated and reduces pain and analgesic use in women with dysmenorrhoea. However, the neutral quality of research is limited by methodological issues and the mechanism of action remains to be determined.

Mutation analysis for evaluating code translation.

Source-to-source code translation automatically translates a program from one programming language to another. The existing research on code translation evaluates the effectiveness of their approaches by using either syntactic similarities (e.g., BLEU score), or test execution results. The former does not consider semantics, the latter considers semantics but falls short on the problem of insufficient data and tests. In this paper, we propose MBTA (Mutation-based Code Translation Analysis), a novel application of mutation analysis for code translation assessment. We also introduce MTS (Mutation-based Translation Score), a measure to compute the level of trustworthiness of a translator. If a mutant of an input program shows different test execution results from its translated version, the mutant is killed and a translation bug is revealed. Fewer killed mutants indicate better code translation. MBTA is novel in the sense that mutants are compared to their translated counterparts, and not to their original program's translation. We conduct a proof-of-concept case study with 612 Java-Python program pairs and 75,082 mutants on the code translators TransCoder and j2py to evaluate the feasibility of MBTA. The results reveal that TransCoder and j2py fail to translate 70.44% and 70.64% of the mutants, respectively, i.e., more than two-thirds of all mutants are incorrectly translated by these translators. By analysing the MTS results more closely, we were able to reveal translation bugs not captured by the conventional comparison between the original and translated programs.

Reliability and Validity of the Composite Activity-Related Fall Risk Scale.

Introduction: The newly developed Composite Activity-related Risk of Falls Scale (CARFS) is designed to measure composite activity-related risk of falls (CARF) in relation to the activity-specific fear of falling and physical behavior. This study tested the reliability and validity of the CARFS in older people with various health statuses and persons with stroke or spinal cord injury. Methods: Participants included 70 older adults, 38 persons with stroke, and 18 with spinal cord injury. They were first surveyed using a combined questionnaire including the CARFS and activity-specific balance confidence (ABC) scale in addition to items asking for personal and disease-related information, fall history, walking independence levels for examining internal consistency, ceiling and floor effects, and convergent validity in each participant group. One week after the initial survey, 33 older participants were reexamined using the CARFS to analyze test-retest reliability, where a minimal detectable change was found. Significance was set at α = 0.05 for all analyses. Results: The CARFS showed excellent test-retest reliability in the dimensions of fear of falling, physical behavior, and CARF [ICC (3,1) = 0.972, 0.994, and 0.994, respectively for their overall score], with a minimal detectable change of 3.944 in the older population. The internal consistency of CARFS items was excellent in the older participants, good in participants with stroke or spinal cord injury (Cronbach's alpha = 0.945, 0.843, 0.831 in each participant group, respectively). No ceiling and floor effects were demonstrated in the wide range of people. For the convergent validity, overall CARF score was significantly correlated with the average ABC score in each participant group (rho = -0.824, -0.761, and -0.601, respectively; p < 0.01), and was significantly correlated with walking independence levels in each participant group (rho = -0.636, -0.423, and -0.522, respectively; p < 0.01). It showed weak correlation with the number of previous falls only in participants with stroke (rho = 0.291, p = 0.076). Conclusion: The CARFS is a reliable and valid tool for measuring fall risk in older people and persons with stroke or spinal cord injury.

Establishing content validity for a composite activities-specific risk of falls scale:linkage between fear of falling and physical activity.

BACKGROUND: Fear of falling (FoF) and physical activity (PA) are important psychological and behavioral factors associated with falls. No instrument quantifies the link between these two factors to evaluate the risk of falls. We aimed to design a scale linking FoF with PA (Composite Activities-specific Risk of Falls Scale, CARFS) for people with various disability levels. METHODS: First, we designed a questionnaire comprising 40 balance-related activities from the International Classification of Functioning, Disability, and Health (ICF) for a pilot survey. Second, participants were interviewed about their activities-specific FoF degree and PA frequency. The participants comprised 30 community-dwelling older adults, hospitalized patients with strokes, and those with spinal cord injuries, each with different disability levels. Third, the content validity of the items was evaluated twice by 12 experienced rehabilitation professionals: one based on experience and the other on the survey responses. Items with a higher than moderate relevance in both evaluations were included in the CARFS. The panel of professionals discussed and voted on the contribution of FoF and PA on the CARF score. Finally, the scale sensitivity in distinguishing disability levels was analyzed to evaluate the population suitability to the CARFS. RESULTS: The CARFS included 14 activities. A five-point Likert scale was used to quantify degree of FoF (A) and frequency of PA (B). The CARF score (C), which was determined using the eq. C = A+(4-B) + A × B/2, reflected sensitivity to disability levels in most items. CONCLUSIONS: The CARFS has strong content validity for measuring risk of falls in relation to the FoF and PA of people with various disability levels. It has a potential to provide a guide for designing individualized exercise- and behavior-focused fall prevention programs and enable the precise trtrun 0acking of program effectiveness as a multidimensional outcome measure.

Single-centre Experience of Patients with Metastatic Urothelial Cancer Treated with Chemotherapy Following Immune Checkpoint Inhibition.

There are few data on outcomes for patients with metastatic urothelial carcinoma (MUC) who receive chemotherapy (CT) after progression on immune checkpoint inhibitors (ICIs). We carried out a retrospective single-centre analysis of MUC patients who progressed after ICI and then received CT. Patients fell into two groups: CT-naive (no prior-CT) and CT-pretreated (platinum-based CT followed by ICI on progression). The response rate (RR), progression-free survival (PFS), and duration of response (DOR) were assessed. A total of 29 patients received CT following progression on ICI. The median follow-up was 17.0mo (interquartile range 9.1-20.5mo). In the CT-naive group (n=17), 53% had a partial response, 18% had stable disease, and 29% had progressive disease. In the CT-pretreated group (n=12) 17% had a partial response, 67% had stable disease, and 16% had progressive disease. The median PFS was 6.4mo (95% confidence interval [CI] 3.8-9.1) in the CT-naive and 4.4mo (95% CI 1.5-7.3) in the CT-pretreated group. The median DOR was 8.1mo (range 5.1-11.1) among the ten patients with a response to CT after ICI in both groups. Some 38% of patients in the CT-naive and 17% in the CT-pretreated group had dose reductions on post-ICI CT. CT and ICI can be sequenced after previous chemotherapy exposure, although this does not induce long-term durable remissions in most patients. PATIENT SUMMARY: We looked at outcomes for patients with metastatic bladder cancer who received chemotherapy after the cancer got worse while on immunotherapy. We found that patients can be safely treated with further chemotherapy. However, the positive effects of chemotherapy will not be durable in the majority of patients.

Associations of intensity, duration, cumulative dose, and age at start of smoking, with thyroid cancer in Chinese males: A hospital-based case-control study in Zhejiang Province.

INTRODUCTION: There has been considerable research on the association between smoking status and thyroid cancer risk in males, yet the findings are inconsistent. In this study, we investigated the associations of intensity, duration, cumulative dose, and age at start of smoking, with thyroid cancer in Chinese males. METHODS: From a 1:1 matched case-control study conducted between 2015 and 2017 in Zhejiang Province, China, 676 pairs of male subjects were included in the analysis. The associations between smoking characteristics and thyroid cancer were evaluated in logistic regression models by odds ratios (ORs) with 95% confidence intervals (CIs). RESULTS: Compared with never smokers, the former smokers were 0.096 times (95% CI: 0.012-0.778) less likely to have thyroid cancer. The significant inverse association was not observed in current smokers (OR=0.333; 95% CI: 0.084-1.322). Among both former and current smokers, higher smoking intensity (>10 cigarettes/day), duration (>15 years), and cumulative dose of smoking (>10 packyears) were significantly associated with reduced occurrence of thyroid cancer. CONCLUSIONS: Our findings indicate that former smoking is inversely associated with thyroid cancer occurrence in Chinese males. The reduction in the occurrence of thyroid cancer was also confirmed for both former and current smokers with higher smoking intensity, duration, and cumulative dose.

Histological and Behavioral Phenotypes of a Novel Mutated APP Knock-In Mouse.

Gene mutations within amyloid precursor protein (APP or AßPP) and/or presenilin 1 (PS1) genes are determinants of familial Alzheimer's disease (fAD) and remain fundamental for experimental models. Here, we generated a neuronal knock-in mouse (PLB2APP) with mutated human APPSwe/Lon and investigated histopathology and behavioral phenotypes. Additionally, PLB2APP mice were cross-bred with a presenilin (PS1A246E) line to assess the impact of this gene combination. Immunohistochemistry determined amyloid-ß (Aß) pathology, astrogliosis (via GFAP labelling), and neuronal densities in hippocampal and cortical brain regions. One-year old PLB2APP mice showed higher levels of intracellular Aß in CA1, dentate gyrus, and cortical regions compared to PLBWT controls. Co-expression of PS1 reduced hippocampal but elevated cortical Aß build-up. Amyloid plaques were sparse in aged PLB2APP mice, and co-expression of PS1 promoted plaque formation. Heightened GFAP expression followed the region-specific pattern of Aß in PLB2APP and PLB2APP/PS1 mice. Behaviorally, habituation to a novel environment was delayed in 6-month-old PLB2APP mice, and overall home-cage activity was reduced in both lines at 6 and 12 months, particularly during the dark phase. Spatial learning in the water maze was impaired in PLB2APP mice independent of PS1 expression and associated with reduced spatial navigation strategies. Memory retrieval was compromised in PLB2APP mice only. Our data demonstrate that low expression of APP is sufficient to drive histopathological and cognitive changes in mice without overexpression or excessive plaque deposition. AD-like phenotypes were altered by co-expression of PS1, including a shift from hippocampal to cortical Aß pathology, alongside reduced deficits in spatial learning.

What Is the Arrhythmic Substrate in Viral Myocarditis? Insights from Clinical and Animal Studies.

Sudden cardiac death (SCD) remains an unsolved problem in the twenty-first century. It is often due to rapid onset, ventricular arrhythmias caused by a number of different clinical conditions. A proportion of SCD patients have identifiable diseases such as cardiomyopathies, but for others, the causes are unknown. Viral myocarditis is becoming increasingly recognized as a contributor to unexplained mortality, and is thought to be a major cause of SCD in the first two decades of life. Myocardial inflammation, ion channel dysfunction, electrophysiological, and structural remodeling may play important roles in generating life-threatening arrhythmias. The aim of this review article is to examine the electrophysiology of action potential conduction and repolarization and the mechanisms by which their derangements lead to triggered and reentrant arrhythmogenesis. By synthesizing experimental evidence from pre-clinical and clinical studies, a framework of how host (inflammation), and viral (altered cellular signaling) factors can induce ion electrophysiological and structural remodeling is illustrated. Current pharmacological options are mainly supportive, which may be accompanied by mechanical circulatory support. Heart transplantation is the only curative option in the worst case scenario. Future strategies for the management of viral myocarditis are discussed.

DVP parametric imaging for characterizing ovarian masses in contrast-enhanced ultrasound.

AIM: To evaluate whether parametric imaging with contrast-enhanced ultrasound is an approach capable of for the differential diagnosis of ovarian masses. MATERIALS AND METHODS: The authors analysed 50 cases of ovarian masses by routine ultrasound and contrast-enhanced ultrasound with a new dedicated parametric image processing software-Sonoliver. The angiogenesis and blood perfusion mode on a digital video recorder were recorded and the morphological characteristics of time-intensity curve (TIC) and dynamic vascular pattern (DVP) curve were subsequently described. The quantity factor, including time to peak (TTP), maximum intensity (IMAX), rise time, (RT), mean transit time (mTT), generated by Sonoliver software were compared in both histological gradings. RESULTS: There were 24 cases (86%) displaying mainly hypo-enhanced with blue imaging in those with benign masses and 15 cases (68%) displaying mainly hyper-enhanced imaging with red in those with malignant masses. The difference was statistically significant (p < 0.05). DVP curves were unipolar below the baseline in 23 cases (82%) of benign masses and unipolar above the baseline in 15 cases (68%) of malignant masses. IMAX, TTP, and mTT were all significantly higher in those with malignant masses than those with benign ones (all p < 0.05), but, no statistical difference in the RT between the two groups was found (p > 0.05). CONCLUSIONS: According to the results, DVP parametric imaging is a new approach capable of differential diagnoses of overian masses with contrast-enhanced ultrasound.

ATPase activity of Mycobacterium tuberculosis SecA1 and SecA2 proteins and its importance for SecA2 function in macrophages.

The Sec-dependent translocation pathway that involves the essential SecA protein and the membrane-bound SecYEG translocon is used to export many proteins across the cytoplasmic membrane. Recently, several pathogenic bacteria, including Mycobacterium tuberculosis, were shown to possess two SecA homologs, SecA1 and SecA2. SecA1 is essential for general protein export. SecA2 is specific for a subset of exported proteins and is important for M. tuberculosis virulence. The enzymatic activities of two SecA proteins from the same microorganism have not been defined for any bacteria. Here, M. tuberculosis SecA1 and SecA2 are shown to bind ATP with high affinity, though the affinity of SecA1 for ATP is weaker than that of SecA2 or Escherichia coli SecA. Amino acid substitution of arginine or alanine for the conserved lysine in the Walker A motif of SecA2 eliminated ATP binding. We used the SecA2(K115R) variant to show that ATP binding was necessary for the SecA2 function of promoting intracellular growth of M. tuberculosis in macrophages. These results are the first to show the importance of ATPase activity in the function of accessory SecA2 proteins.

Analysis of the CDR3 region of alpha/beta T-cell receptors (TCRs) and TCR BD gene double-stranded recombination signal sequence breaks end in peripheral blood mononuclear cells of T-lineage acute lymphoblastic leukemia.

Recently, numerous reports have highlighted the restriction of the CDR3 length of T-cell receptor (TCR) beta chain in T-cells infiltrating solid tumors and hematological malignancies. However, these studies ignored the restriction of CDR3 length of TCR alpha chain and few of them attempted to reveal the mechanisms of the oligo-clonal expansion of T cells in the tumors. The primary aims of this study were twofold to: (i) analyze the CDR3 length of TCR alpha and beta chain in peripheral blood mononuclear cells of T-lineage acute lymphoblastic leukemia (T-ALL); and (ii) discover the relationship between the clonality of T cells and the process of TCR rearrangement in peripheral T cells. To this end, we investigated the TCR BV and TCR AV family spectratypes of two T-ALL patients and healthy controls using the immunoscope spectratyping technique. We found that the spectratypes exhibited a Gaussian distribution in healthy controls. However, the TCR repertoires of the two patients were highly restricted in the number of different TCR BV and TCR AV family members present. Furthermore, we found that the peripheral blood mononuclear cells (PBMC) of two T-ALL patients had the recombination signal sequence (RSS) 5'- and 3'-breaks end in the TCR BD2 gene using a specialized ligation-mediated polymerase chain reaction, implying the ongoing recombination of the TCR beta gene. Analysis of the particular CDR3 length of TCR alpha/beta T cells might be helpful for further study of the individualized therapy of T-ALL. This information will also be helpful in exploring new immunological pathogenesis and facilitating the design of a T-ALL vaccine, as well as in improving our understanding of healthy human T-cell development.

Novel halo-oxo-allenic fatty ester derivatives from epoxidized methyl santalbate (methyl trans-11-octadecen-9-ynoate).

Methyl santalbate (methyl trans-11-octadecen-9-ynoate) from Sandal wood seed oil, Santalbum alum) was epoxidized to methyl trans-11,12-epoxy-octadec-9-ynoate (1). Treatment of compound 1 with tetrabutylammonium dihydrogentrifluoride, and boron trifluoride etherate gave the corresponding anti- (2a) (57%) and syn- (2b) (35%) fluorohydrin derivatives, respectively. These reactions were regio- and stereoselective in nature. The structures of the anti- and syn- isomers were confirmed by NMR spectroscopy. Ring opening of the epoxy system of compound 1 with lithium chloride gave the anti-chlorohydrin derivative (3) (89%). Oxidation of either compound 2a or 2b gave the same fluoro-keto acetylenic fatty ester (4) (75%), and compound 3 on chromic acid oxidation yielded the corresponding chloro-keto acetylene (5) (73%). Isomerization of compounds 4 and 5 with potassium carbonate in dichloromethane furnished the requisite fluoro-allenic (6) (63%, methyl 11-fluoro-12-oxo-9,10-octadecadienoate) and chloro-allenic (7) (80%, methyl 11-chloro-12-oxo-9,10-octadecadienoate) C(18) fatty esters. All products were confirmed by a combination of spectrometric and spectroscopic techniques.

Fullerenoid lipids: first synthesis of structured triacylglycerols containing an Aza-[60]fullerene unit.

Some 1,2- and 1,3-diacyl glycerols (with acyl groups as stearyl, oleyl, linoleyl, or stearolyl) were synthesized by conventional methods. The diacyl glycerols were esterified with 6-bromo-hexanoic acid to give the corresponding bromo-triacylglycerols (of the type AAB and ABA containing a bromo group at the distal part of the hexanoate chain). The bromo function was transformed to an azide group by reaction of the bromo-triacylglycerols with sodium azide. The resulting azido-triacylglycerols were then reacted with [60]fullerene to give the requisite aza-fullerenoid triacylglycerol of the type ABA or AAB (45-62% yield based on the amount of [60]fullerene reacted). The nitrogen atom attached to the carbon cage formed a "[5,6]open" type aza substructure, which was confirmed by the appearance of 31-32 signals in the region of deltaC 133-148 (carbon shifts of Sp2 carbons of the cage) in the 13C nuclear magnetic resonance spectra. The spectroscopic and mass spectrometric properties of these novel fullerenoid triacylglycerols are reported.

Novel azido fatty acid ester derivatives from conjugated C(18) enynoate.

Methyl octadec-11Z-en-9-ynoate (1) was epoxidized to give methyl 11,12-Z-epoxy-octadec-9-ynoate (2, 81%). Acid catalyzed ring opening of the epoxy ring of compound 2 gave methyl 11,12-dihydroxy-octadec-9-ynoate (3, 80%). The latter was treated with mesyl chloride to yield methyl 11,12-dimesyloxy-octadec-9-ynoate (4, 76%). Reaction of compound 4 with sodium azide furnished methyl 11-azido-12-mesyloxy-octadec-9-ynoate (5a, 49%) and methyl 11-azido-octadec-11E-en-9-ynoate (5b, 24%). Compound 2 was semi-hydrogenated over Lindlar catalyst to give methyl 11,12-Z-epoxy-octadec-9Z-enoate (6, 90%). This allylic epoxy fatty ester (6) was reacted with sodium azide to give a mixture of methyl 11-azido-12-hydroxy-octadec-9Z-enoate (7a) and methyl 9-azido-12-hydroxy-octadec-9E-enoate (7b), which could not be separated into individual components by silica chromatography. Chromic acid oxidation of the mixture of compounds 7a and 7b furnished methyl 9-azido-12-oxo-octadec-10E-enoate (8, 42% based on amount of compound 6 used) and an intractable mixture of polar compounds. The various products were characterized by NMR spectroscopic and mass spectral analyses.

Fullerene lipids: synthesis of novel nitrogen-bridged.

Reactions of methyl 6-azido-hexanoate, 8-azidooctanoate, and 12-azido-dodecanoate with [60]fullerene (1) gave the corresponding aza-[60]fullerene ester derivatives (2a-2c, 22-35% based on the amount of [60]fullerene reacted). The nitrogen atom is bonded to the [60]fullerene cage to yield a "[5,6]-open" type aza substructure. This was confirmed by the appearance of 30-31 sp2 signals at deltac 133-147 in the carbon nuclear magnetic resonance spectra. Reaction of methyl 11-azido-7-undecynoate with [60]fullerene furnished a mixture of aza-[60]fullerene (2d, 53%) and aziridine-[60]fullerene (2e, 38%) ester derivatives. Compound 2e was identified as the "[6,6]-closed" type aziridine-[60]fullerene derivative, which displayed 10 sp2 signals in the region deltac 140-145 and one signal at deltac 85.05 for the sp3 carbons of the cage. Refluxing a solution of compound 2d in toluene for 50 h gave about 50% yield of compound 2e, but not vice versa.

Cyclodehydration reactions of methyl 9,10-; 10,12-; and 9,1 2-dioxostearates with 1,2-diaminoethane under ultrasonic irradiation.

Reaction of methyl 9,10-dioxostearate (1) and 9,12-dioxostearate (2) with 1,2-diaminoethane under concomitant ultrasonic irradiation (10-15 min, 60 degrees C) in water furnished the corresponding 2,3-dihydropyrazine (4, 79%) and 1,2,3,4-tetrahydro-1,4-diazocine (5, 70%) derivatives, respectively. Reaction of methyl 10,12-dioxostearate (3) with 1,2-diaminoethane was successful only when glacial acetic acid was used instead of water under ultrasonic irradiation (4 x 10 min, 70 degrees C) to give a 2,3-dihydro-1H-1,4-diazepine (6, 95%) derivative. The structures of these novel six-membered (4), seven-membered (6), and eight-membered (5) N-heterocyclic fatty ester derivatives were confirmed by a combination of infrared, nuclear magnetic resonance spectroscopic and mass spectral analyses.

Novel lipidic enaminones from a C18 keto-allenic ester.

Primary amines (ammonia, methyl, propyl, octyl, octadecyl, phenyl, benzyl, phenethyl) including methyl esters of amino acids (glycine, DL-alanine, L-valine, L-leucine, L-tyrosine, and L-methionine), and secondary amines (dimethyl, diethyl, dipropyl, diisopropyl, dioctyl, and diphenyl) attack regiospecifically the central carbon atom of the allene system of methyl 12-keto-9,10-octadecadienoate (1) to give the corresponding lipidic enaminone derivatives (2-21) with an average yield of 77%. The E- and Z-configuration of the enaminone system of these novel lipid derivatives was confirmed by infrared and nuclear magnetic resonance spectroscopic techniques. Primary amines furnished Z-enaminones, while secondary amines gave E-enaminones.

Fullerene lipids: synthesis of C60 fullerene derivatives bearing a long-chain saturated or unsaturated triester system.

Tris(hydroxymethyl)aminomethane was successfully esterified with saturated and unsaturated long-chain fatty acids. The resulting amino-triester intermediates were successively reacted with chloroacetyl chloride, sodium azide, and C60 fullerene. Spectral evidence showed that the aziridine ring is joined to the junction of 16,6]-fused rings of the fullerene. The structures of the various C60 fullerene derivatives bearing a long-chain saturated or unsaturated triester system were characterized by spectroscopic and spectrometric methods.

Lipase specificity toward some acetylenic and olefinic alcohols in the esterification of pentanoic and stearic acids.

The esterification of five medium- and long-chain acetylenic alcohols (2-nonyn-1-ol, 10-undecyn-1-ol, 6-octadecyn-1-ol, 9-octadecyn-1-ol, and 13-docosyn-1-ol), seven olefinic alcohols (cis-3-nonen-1-ol, 10-undecen-1-ol, cis-6-octadecen-1-ol, cis-9-octadecen-1-ol, trans-9-octadecen-1-ol, trans-9, trans-11-octadecadien-1-ol, cis-9,cis-12-octadecadien-1-ol), and four short-chain unsaturated alcohols (allyl alcohol, 3-butyn-1-ol, 3-pentyn-1-ol, and cis-2-penten-1-ol) with pentanoic or stearic acid in the presence of various lipase preparations was studied. With the exception of 2-nonyn-1-ol, where Lipase AY-30 (Candida rugosa) was used as the biocatalyst, the esterification of C11, C18, and C22 acetylenic alcohols with pentanoic acid appeared to be generally unaffected by the presence of an acetylenic bond in the alcohol as relatively high yields of the corresponding esters (78-97%) were obtained. However, medium- and long-chain olefinic alcohols were discriminated by Lipase AY-30, Lipolase 100T (Rhizomucor miehei), and especially by porcine pancreatic lipase (PPL), when esterification was conducted with pentanoic acid. Esterification of medium- and long-chain acetylenic or olefinic alcohols with a long-chain fatty acid, stearic acid, was very efficient except when Lipase AY-30 and Lipolase 100T were used. Short-chain unsaturated alcohols were much more readily discriminated. 3-Pentyn-1-ol and 3-butyn-1-ol were difficult (<5% yield) to esterify with pentanoic or stearic acid in the presence of Lipase AY-30 and PPL, respectively. Very low yields (<26%) of esters were produced when 3-butyn-1-ol and 3-pentyn-1-ol were reacted with pentanoic or stearic acid, when catalyzed by lipase from Candida cylindracea. No reaction took place between 3-butyn-1-ol and stearic acids in the presence of Lipase AY-30. Esterification of short-chain acetylenic and olefinic alcohols was most efficiently achieved with Lipolase 100T (Rhizomucor miehei), Lipozyme IM20 (Rh. miehei), or Novozyme 435 (Candida antarctica) as the biocatalyst.