Investigation of unified impact of Ti adatom and N doping on hydrogen gas adsorption capabilities of defected graphene sheets.

In this work, we studied the hydrogen adsorption capabilities of functionalized graphene sheets containing a variety of defects (D-G) via molecular dynamics (MD) simulations that govern the mechanisms involved in hydrogen adsorption. Specifically, the graphene sheets containing monovacancy (MV), Stone-Wales (SW), and multiple double vacancy (DV) defects were functionalized with Ti and N atoms to enhance their hydrogen adsorption capacity. We measured the adsorption capacities of the N-/D-G sheets with varying concentrations of Ti adatoms at 300 K and 77 K temperatures and various pressures. Our study revealed that the increasing concentration of Ti adatoms on the D-G sheets led to a significant improvement in the hydrogen adsorption capacity of the graphene sheets. The DV(III)-G sheets showed the maximum adsorption capacity at 300 K because the DV(III)-G sheets had a small number of large-sized pores that bind hydrogen with high binding energy. Thus, hydrogen remained adsorbed even at higher temperatures (300 K). The N doping on the D-G sheets initially reduced their hydrogen adsorption capabilities; however, the N-D-G sheets enhanced their hydrogen adsorption capacity with the increasing concentrations of Ti adatoms. Compared to all other defect types, the Ti-N-DV(III)-G sheet with a Ti concentration of 10.5% showed a hydrogen uptake of 5.5 wt% at 300 K and 100 bar pressure. Thus, the N doping and Ti implantations improved the hydrogen storage capabilities of the graphene sheets, and these findings helped design solid-state hydrogen storage systems operating at ambient conditions and moderate pressure ranges.

Distribution and characterization of microplastics in beach sand from three different Indian coastal environments.

The occurrence of microplastic particles were evaluated on beaches along the Indian coast from three different locations Girgaon Mumbai (Arabian sea coast), Tuticorin, and Dhanushkodi (Bay of Bengal coast). Density separation method was adopted for isolation of microplastics from sand. Isolated microplastics were characterized using three different analytical techniques e.g. fluorescence microscopy (after staining with Nile Red), FTIR and SEM-EDS techniques. Microplastic concentrations in beach sands were from 45 ±â€¯12 # MP kg-1 to 220 ±â€¯50 # MP kg-1 of dry sand. The order of abundance of plastic type was polyethylene (43%) > polyethylene terephthalate (17.3%) ≈ polystyrene (17%) > polypropylene (12.3%) > Others (11%) > polyvinylchloride (1.33%), and very similar profile was observed for all monitored locations. SEM images show microplastics surfaces with characteristic cracks, suggests their polymer aging, mechanical and oxidative weathering, which was found highest for the microplastics collected from Mumbai.

Effects of GnRH, a progesterone-releasing device, and energy balance on an oestrus synchronisation program in anoestrous dairy cows.

OBJECTIVE: The aim of this research was to study the roles of the day 0 energy balance and gonadotrophin-releasing hormone (GnRH) and progesterone levels on dominant follicle (DF) and corpus luteum (CL) development during the first 7 days of a gonadotrophin-prostaglandin-gonadotrophin (GPG) + progesterone (P4) program in anoestrous dairy cows. METHODS: Cows (n = 81) were allocated to one of the three treatments: (1) GPG + P4 (days 0 and 9, 100 µg GnRH; day 0-7, intravaginal P4 device; day 7, 500 µg PGF2α ); (2) GPG (as for treatment 1 but excluding the P4 device) and (3) prostaglandin + GnRH + P4 (as for treatment 1, but excluding day 0 GnRH). DF and CL size, plasma concentrations of insulin, insulin-like growth factor-I (IGF-I) and non-esterified fatty acid (NEFA) were measured on days 0 and 7. RESULTS: The proportion of cows with a CL on day 7 was significantly different between groups (GPG: 78%, GPG+P4: 69%, PGF2α + GnRH + P4: 42%, P = 0.02). The CL volume on day 7 was significantly associated with treatment, treatment by time postpartum and plasma concentrations of insulin, IGF-I and NEFA. CONCLUSION: In cows without a CL present on day 0 of an oestrus synchronisation program, removal of the day 0 GnRH treatment led to reduced CL development; however, no effect of adding progesterone was found. In contrast, in cows with a CL present on day 0 inclusion of a progesterone device led to a higher CL volume, but removal of the first GnRH injection had no effect. Response to the treatment was affected by plasma concentrations of insulin, IGF-I and NEFA.

Distribution of PAHs in different compartment of creek ecosystem: Ecotoxicological concern and human health risk.

We report levels of polycyclic aromatic hydrocarbons in sediment, seawater, fish and crab samples from Thane creek, India. Concentrations of sixteen USEPA PAH in sediments varies from 874 to 1925ngg-1, dry weight (dw) in winter, between 219-495ngg-1 in summer. In seawater Σ16 PAHs concentration during winter was recorded 706±193ngL-1, and during summer 337±79ngL-1. Total concentrations of PAHs in consumable portion of lizard fish, bombay duck and crab were found 156.8±18 and 122±24.5ngg-1, 117.4±17.65ngg-1 and 95.8±16.2ngg-1, 348±94.5 and 95.62±31.9ngg-1 wet weight (ww) in summer and winter respectively. PAHs concentration were compared with sediments quality guidelines viz. ERL-ERM, TEL-PEL indexes for finding ecotoxicological risk on marine organism. The ILCR values were above public screening criteria for carcinogens.

Polonium in size fractionated mainstream cigarette smoke, predicted deposition and associated internal radiation dose.

In this study, size fractionated mass and 210Po activity concentrations in mainstream cigarette smoke (MCS) were monitored for three popular cigarette brands. Size segregated collection of MCS was carried out using a cascade type impactor, while mass and 210Po activity concentration were analyzed gravimetrically and alpha spectrometry (following the radiochemical separation) respectively. Multiple-Path Particle Dosimetry (MPPD V2.11) model is used for prediction of deposition fraction calculations for the MCS deposition in different compartment of human respiratory tract. The activity concentration of 210Po is founds 10.56 ± 2.46 mBq per cigarette for the tested cigarette brands. 210Po size distribution indicates most of this associates with fine fraction (Dp < 2.23 µm) of cigarette smoke. The committed annual effective dose to smokers (smoking on an average 20 cigarette a day), considering the 210Po and 210Pb concentrations (assuming it is in secular equilibrium with 210Po) in MCS, was estimated between 0.22 and 0.40 mSv, with mean value of 0.30 mSv for tested cigarette brands. Considering the risk factor of fatal cancer due to radiation exposure of lung (exposure time of 30 years); the average collective estimated fatal cancer risk is estimated as 1.5 × 10-4 due to 210Po and 210Pb exposure to smokers.

Distribution and estrogenic potential of endocrine disrupting chemicals (EDCs) in estuarine sediments from Mumbai, India.

Endocrine disrupting chemicals (EDCs) are responsible for inappropriate development and they alter the hormonal and homeostatic systems of organism. Phthalates (PAEs), bisphenol A (BPA) and other EDCs were monitored in surface sediments at different stations across Thane Creek, India. Analysis of PAEs was carried out using GC-MS technique, while BPA and other EDCs were analyzing on UPLC-PDA instrument. Di-n-butyl phthalate (DBP) had the highest concentration among all fourteen analyzed phthalates ranges between 0.13 and 0.4 mg kg(-1); and was detectable in all sediment samples. Strong correlation (r = 0.95, p < 0.01) was observed between total organic carbon (TOC, %) and total PAEs. BPA was also detected in all samples; average BPA concentration varies from 16.3 to 35.79 µg kg(-1) with mean value 25.15 µg kg(-1) dry weight of sediment. Synthetic EDCs such as 4-para-nonylphenol (NP) and 4-tert-octylphenol (OP) were also analyzed; and their average concentrations were founds to be 356.5 and 176 µg kg(-1), respectively. Estrone (E1), 17ß-estradiol (E2), and 17α-ethinylestradiol (EE2) were the main contributors to the overall estradiol equivalent concentration (EEQs) in sediment, their average total percentage contributions is more than 90 %.

Association of p53 codon72 Arg>Pro polymorphism with susceptibility to nasopharyngeal carcinoma: evidence from a case-control study and meta-analysis.

Tumor suppressor p53 is a critical player in the fight against cancer as it controls the cell cycle check point, apoptotic pathways and genomic stability. It is known to be the most frequently mutated gene in a wide variety of human cancers. Single-nucleotide polymorphism of p53 at codon72 leading to substitution of proline (Pro) in place of arginine (Arg) has been identified as a risk factor for development of many cancers, including nasopharyngeal carcinoma (NPC). However, the association of this polymorphism with NPC across the published literature has shown conflicting results. We aimed to conduct a case-control study for a possible relation of p53 codon72 Arg>Pro polymorphism with NPC risk in underdeveloped states of India, combine the result with previously available records from different databases and perform a meta-analysis to draw a more definitive conclusion. A total of 70 NPC patients and 70 healthy controls were enrolled from different hospitals of north-eastern India. The p53 codon72 Arg>Pro polymorphism was typed by polymerase chain reaction, which showed an association with NPC risk. In the meta-analysis consisting of 1842 cases and 2330 controls, it was found that individuals carrying the Pro allele and the ProPro genotype were at a significantly higher risk for NPC as compared with those with the Arg allele and the ArgArg genotype, respectively. Individuals with a ProPro genotype and a combined Pro genotype (ProPro+ArgPro) also showed a significantly higher risk for NPC over a wild homozygote ArgArg genotype. Additionally, the strength of each study was tested by power analysis and genotype distribution by Hardy-Weinberg equilibrium. The outcome of the study indicated that both allele frequency and genotype distribution of p53 codon72 Arg>Pro polymorphism were significantly associated with NPC risk. Stratified analyses based on ethnicity and source of samples supported the above result.

Polymorphisms of extrinsic death receptor apoptotic genes (FAS -670 G>A, FASL -844 T>C) in coronary artery disease.

Apoptosis plays an important role in atherogenesis and rupture of vulnerable plaques in coronary artery disease. FAS and FAS ligand (FASL) induce apoptosis when FAS binds to FAS-L. However sFas blocks apoptosis by binding to FAS and FASL or sFasL. The present study is sought to examine the role of extrinsic apoptotic genes (FAS, FASL) polymorphism and serum levels of FAS, FASL in the pathogenesis and susceptibility to CAD in south Indian population. The study included 300 CAD patients and 300 healthy controls. Lipid profiles, sFas, sFasL were estimated by commercially available kits. FAS -670 G>A, FASL -844 T>C genotypes were analyzed by PCR-RFLP. Secondary structures of pre mRNA were analyzed by the Vienna RNA webserver and gene-gene and gene-environment interactions were determined by MDR analysis. Total cholesterol, triglyceride and LDL levels were significantly high in CAD patients compared to the controls. Molecular analysis revealed that the frequency of the AA genotype of FAS (54% vs 27%) and CC genotypes of FASL (10.3% vs 1.3%) were high in CAD patients compared to controls. Secondary structure analysis of FAS and FASL confirmed our molecular analysis. sFas levels were low while serum sFasL were high in CAD patients. MDR analysis revealed synergistic effects of gene polymorphisms and additive effects of epidemiological factors on risk of CAD. Polymorphisms of FAS (-670 G/A), FASL (-844 T/C) and their circulating levels play an important role in the pathology of CAD.

Primary Peritoneal Papillary Serous Cystadenocarcinoma - A Rare Malignancy.

Primary peritoneal papillary serous carcinoma is a rare primary malignancy diffusively involving the peritoneum of abdomen and pelvis. Epithelial ovarian cancers and primary peritoneal cancers arise from the common germinal epithelium which develops from the coelomic epithelium. Due to a common embryonic origin of the ovary and the peritoneum, carcinoma of the ovary and primary peritoneal carcinoma have much histological similarity. However the incidence of Primary peritoneal serous carcinoma is considerably lower than that of epithelial ovarian cancer and is mostly seen in elderly women. Early stages of this disease may be asymptomatic; symptoms of the advance stages of the disease include abdominal distention, abdominal lump, non-specific abdominal pain, vomiting and dyspnoea all as a result of massive ascites. Patients diagnosed with primary peritoneal papillary serous carcinoma are treated using the same staging, surgical and chemotherapeutic approach as epithelial ovarian cancer because of the similarities in biological behavior.

Screening for diabetes among presumptive tuberculosis patients at a tertiary care centre in Pondicherry, India.

SETTING: Designated microscopy centre (DMC) attached to a tertiary care centre in Pondicherry, India. OBJECTIVES: To determine 1) the proportion of diabetes mellitus (DM), 2) the additional yield of newly diagnosed DM cases, and 3) the number needed to screen (NNS) to find a new case of DM among presumed TB patients. DESIGN: An institution-based cross-sectional study was carried out among 650 presumed TB patients attending the DMC. Capillary blood glucose was measured using fasting blood sugar and/or oral glucose tolerance test, and evaluated according to the World Health Organization criteria. RESULTS: Of 570 presumed TB patients evaluated for DM, 121 (21.2%) were found to be diabetic. Of these, 69 were previously known to have DM, while 52 were newly diagnosed. The additional yield of diabetes was 43%. The NNS to detect a new case of DM was 11; among those aged >40 years, the NNS was 9.3, and among smear-positive TB patients it was 4.6. CONCLUSION: One fifth of the presumed TB patients had diabetes, and nearly half of these patients were newly diagnosed. Opportunity screening of presumed TB patients for DM in routine care will help in early detection of diabetes and pre-diabetes.

Effects of progesterone inclusion in a gonadotropin-prostaglandin-gonadotropin programme on follicular dynamics and ovulation synchronisation of pasture-based dairy cows with anoestrous.

The aim of this study was to evaluate how the addition of a progesterone device to a gonadotropin-prostaglandin-gonadotropin (GPG) programme in dairy cows with postpartum anovulatory anoestrus affected ovarian follicular dynamics and the synchronisation of ovulation. Twenty-two dairy cows were randomly assigned to either GPG (Day 0: 100 µg GnRH, Day 7: 500 µg PGF2α, Day 9: 100 µg GnRH, Day 0-7: Day 10) or GPG with a progesterone device from Day 0 to 7 (GPG+P4). Ovarian follicular dynamics and ovulation synchronisation were studied using transrectal ultrasonography. Compared to the GPG+P4, GPG alone resulted in a relatively larger mean dominant follicle size and a higher mean peripheral oestradiol concentration (74.9 pg ∗ day vs. 60.6 pg ∗ day; P=0.002); however, there was much greater variation in follicle diameter in the group treated with GPG (7.8-22 mm vs. 10.8-17.5mm in GPG+P4) and this may, at least partly explain why only 7/11 cows in this group ovulated within 48 h of the Day 9 GnRH injection compared to 10/10 of the cows in the GPG+P4 group. These results suggest that differences in follicular dynamics between GPG and GPG+P4 programmes are not a key driver of the difference in conception rate, but further studies are required to better assess the role of ovulation synchronisation.

Microbial colonisation of orthopaedic tourniquets: a potential risk for surgical site infection.

Pneumatic tourniquets have been used in orthopaedic surgery to get avascular fields. Sixteen such tourniquets were analysed for microbial colonisation. Samples were taken from two inner and two outer areas of each tourniquet and cultured on sheep blood agar. Eight of these were wiped with Savlon and the rest with Sterillium solution. Post-treatment samples from the same sites were again cultured. After incubation, colonies from each site were identified and counted. It was observed that the tourniquets were colonised with coagulase-negative staphylococci, Staphylococcus aureus, Bacillus, diphtheroids, Pseudomonas, Acinetobacter, enterococci, enterobacteria, and Candida. On treating with Savlon and Sterillium, there was 92.18% and 95.70% reduction in the colony count, respectively.

Conception rates to fixed-time artificial insemination of two oestrus synchronisation programmes in dairy heifers.

AIM: To evaluate the conception rate to fixed-time artificial insemination (FTAI) of two oestrus synchronisation programmes in dairy heifers on eight farms over 2 years. METHODS: The study was conducted in 2008 and 2010 on eight farms near Palmerston North, New Zealand. Nulliparous Friesian and Friesian×Jersey heifers (13-15 months of age) were randomly allocated to one of two oestrus synchronisation programmes. Group 1 (GPG+P4; n=330), received gonadotrophin-releasing hormone (GnRH) I/M on Day 0, a progesterone (P4)-releasing intravaginal device from Days 0-7, prostaglandin F2α (PGF) I/M on Day 7 and a second dose of GnRH at the time of FTAI on Day 9. The second group (P4+PGF; n=343) received a P4-releasing intravaginal device from Days 0-7, PGF on Day 6 and FTAI on Day 9. Pregnancy was diagnosed from Days 42-52 by transrectal ultrasonography. RESULTS: The overall conception rate was 52.4% and 54.8% for the GPG+P4 and P4+PGF groups, respectively. The odds of conception for the two treatments were not different (OR=0.90; 95% CI=0.67-1.23), nor was there any difference between groups in different years (p=0.58). Farm affected conception rate (p=0.002), but there was no interaction with treatment (p=0.92) . CONCLUSIONS: This study has shown that an alternative synchronisation programme can produce similar results in terms of conception rate to the GPG+P4 treatment, currently commonly used in heifers. More research is required to establish whether other modifications to the GPG+P4 programme can produce similar results at lower costs, and to identify and quantify farm factors which affect the economic benefit of heifer synchronisation. CLINICAL RELEVANCE: This study indicated that synchronising heifers with P4 and PGF resulted in conception rates equivalent to those resulting from a GPG+P4 treatment, but with reduced drug costs. However, because heifers in the GPG+P4 group received the second GnRH injection at the time of AI, they needed only three yardings as opposed to the four required for the heifers treated with P4 and PGF. Thus, the choice of programme for an individual farm will depend on that farm's circumstances, in particular the cost of yarding the heifers.

Longitudinal extensive transverse myelitis due to tuberculosis: a report of four cases.

Tuberculosis of the central nervous system (CNS) accounts for approximately 1% of all cases of tuberculosis and half of these involve the spine. Intramedullary involvement is rare in tuberculosis and usually present in the form of radiculomyelitis, transverse myelitis, intraspinal granulomas, or thrombosis of anterior spinal artery. Transverse myelitis typically extends two or less spinal segments, whereas longitudinal extensive transverse myelitis (LETM) extends three or more spinal segments in length and may occasionally span all the segments of the spinal cord. LETM is most frequently associated with neuromyelitis optica (NMO). Moreover, associations between NMO and active pulmonary tuberculosis have been suggested by a number of case reports and case series. We present here four cases of spinal tuberculosis that presented with LETM and none of them had a clinical profile fulfilling the diagnostic criteria for NMO.

The effects of exclusion of progesterone or Day 0 GnRH from a GnRH, prostaglandin, GnRH + progesterone program on synchronization of ovulation in pasture-based dairy heifers.

This study evaluated the effect of removing the GnRH injection on Day 0 or the progesterone (P4) device from a GnRH, PGF2α, GnRH (GPG) + P4 program on follicular dynamics and synchronization of ovulation in dairy heifers. Friesian and Friesian × Jersey heifers, in autumn 2009 (n = 35) and spring 2010 (n = 38), were randomly allocated to one of three estrus synchronization programs. The first group (GPG + P4) received 100 µg GnRH on Day 0, a P4-releasing intravaginal device from Days 0 to 7, 500 µg PGF2α on Day 7, and 100 µg GnRH on Day 9, followed by fixed-time artificial insemination 16 to 20 hours later. The program for group 2 (GPG) was the same as group 1 with the exclusion of the P4 device. Group 3 (P + G + P4) was treated the same as group 1, except for the absence of the GnRH treatment on Day 0. Ultrasonography was performed on Days 0, 1, 2, 3, and 7 and then at 12 hourly intervals on Days 9 to 11. Dominant follicle size was affected by both treatment and day, and there was also a significant interaction (P < 0.02) between treatment and day. Mean dominant follicle size was larger in the heifers treated with P + G + P4 on Days 1 to 3 than those treated with GPG + P4 (P < 0.02) and, on Day 2, than those treated with GPG (P = 0.005). However, on Day 7, mean dominant follicle size was larger in heifers treated with GPG than heifers treated with P + G + P4 (P = 0.03). The emergence of a new follicular wave was later in heifers treated with P + G + P4 than heifers, which received a GnRH injection on Day 0 (4.3 ± 0.7 days, compared with combined GPG + P4 and GPG 3.0 ± 0.3 days; P = 0.03). The proportion of heifers that ovulated within the first 48 hours after the Day 9 injection of GnRH was not affected by treatment (GPG, 81%; GPG + P4, 84%; and P + G + P4, 100% [including early ovulation]; P = 0.11). The timing of the ovulation was not different between treatments (P = 0.97).

Distribution and fate of persistent organochlorine pesticides in coastal marine environment of Mumbai.

Multi-compartment monitoring of residue levels of OCPs in coastal marine environment of Mumbai has been studied. The concentration of total HCHs in seawater varied from 0.16 to 15.92 ng/L and concentrations of total DDT varied from 3.01 to 33.21 ng/L. The total HCH concentration in the sediment samples was in the range of 3.8 to 16.2 ng/g. Gamma-HCH contributed almost 55% to the total HCH. In sediment samples the DDT has higher mean concentration in comparison to its metabolite DDE and DDD. The concentration of total HCHs in different marine species varied from 0.87 to 33.73 ng/g and concentrations of total DDT varied from 0.38 to 34.1 ng/g. The variation in the beta-HCH in different compartments is not significant and this could be due to the high persistence and metabolically inactive nature of this isomer. The alpha-HCH is found to be more dominant in fish samples whereas the gamma-HCH is major contributor in the sediment samples.

Assessment of risk to public health posed by persistent organochlorine pesticide residues in milk and milk products in Mumbai, India.

The risk posed by the presence of organochlorine pesticides in milk and milk products was estimated for the population of Mumbai. To determine the levels of organochlorine pesticides in milk and milk products, a monitoring study was carried out in and around Mumbai City. 520 samples of milk and milk products of different brands were considered in this study. A survey was also conducted to determine the mean daily consumption of milk and milk products by different age groups and this data was used to evaluate the daily exposure to the public. Non-cancer effects were evaluated by comparing the predicted exposure distributions to the published guidance values. For chemicals identified as potential human carcinogens, cancer risk was evaluated using standard methodology. The majority of the chlorinated pesticides identified in the milk and milk product samples studied were found to be at levels which do not pose unacceptable risks to the public, with the exception of alpha-HCH. The cancer risk estimated for this chemical slightly exceeds the US EPA guidance value.

Gas exchange of OCPs across the air-water interface at the creek adjoining Mumbai harbour, India.

The concentrations of organochlorine pesticides (OCPs) such as hexachlorocyclohexanes (HCHs), dichlorodiphenyltrichloroethane (DDT) and its metabolite (DDE) and endosulfans were determined in air and water in order to estimate the magnitude and direction of gas flux across the air-water interface at the creek adjoining Mumbai harbour, India. The range of HCH residues in air was found to be between 1.0 and 22.5 pg m(-3) and that in sea-water was between 1.7 to 34.4 ng l(-1) DDT and its metabolite (DDE) residues in air ranged between 2.1 and 80.8 pg m(-3) and in sea-water between 1.4 to 19.2 ng l(-1). The concentrations of beta-endosulfan in air and sea-water samples were found to be 1.0-1.6 pg m(-3) and 1.0-2.6 ng l(-1) respectively. The HCHs revealed positive values of the fluxes (1.001 microg m(-2) d(-1) for alpha-HCH, 0.107 microg m(-2) d(-1) for beta-HCH and 0.455 microg m(-2) d(-1) for gamma-HCH) indicating the tendency to transfer these contaminants from water to air. This implies that the marine water bodies principally act as a source of HCHs. The fluxes for DDTs (p,p'-DDE and p,p'-DDT) also follow the same pattern as HCHs and show high positive values (1.698 microg m(-2) d(-1) for DDE and 2.422 microg m(-2) d(-1) for DDT). The present study suggests the active transfer of these dissolved OCPs into the atmosphere due to volatilization.

The synergistic extraction of thorium(IV) and uranium(VI) with mixtures of 3-phenyl-4-benzoyl-5-isoxazolone and crown ethers.

The extraction of thorium(IV) and uranium(VI) from nitric acid solutions has been studied using mixtures of 3-phenyl-4-benzoyl-5-isoxazolone (HPBI) and dicyclohexano-18-crown-6, benzo-18-crown-6, dibenzo-18-crown-6 or benzo-15-crown-5. The results demonstrate that these metal ions are extracted into chloroform as Th(PBI)(4) and UO(2)(PBI)(2) with HPBI alone and as Th(PBI)(4) . CE and UO(2)(PBI)(2) . CE in the presence of crown ethers (CE). The equilibrium constants of the above species have been deduced by non-linear regression analysis. The addition of a CE to the metal chelate system enhances the extraction efficiency and also improves the selectivities between thorium and uranium. IR spectral data of the extracted complexes were used to further clarify the nature of the complexes. The binding to the CEs by Th(PBI)(4) and UO(2)(PBI)(2) follows the CE basicity sequence but with DC18C6 and DB18C6, steric effects become more important.