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Objectives: The study was designed to estimate daily salt intake, its discretionary use in healthy individuals and to validate three common methods for salt estimation in Pakistani population. Methodology: Information on demography and discretionary salt use was collected from healthy adults (>18 years) along with a blood sample, spot and 24 hour urine samples. Sodium, chloride, potassium levels and serum creatinine were measured using standard methods. For daily salt estimation, three common methods i.e. INTERSALT, Tanaka and Kawasaki were validated for their applicability in local settings. Results: Overall 24 h sodium excretion was 158 mmol/l indicating intake of 8.64 (±4.43) grams salt per day which was significantly associated with male gender (p. <0.004) and adding salt during cooking (p. <0.0001). Most (73%) of the participants know about hazardous effects of high salt intake, however, only 25% consider important to lower salt intake. None of three methods i.e. INTERSALT (bias: -19.64; CCC -0.79), Tanaka (bias: 167.35; CCC -0.37) and Kawasaki (bias: -42.49, CCC -0.79) showed any agreement between measured and estimated 24 hour sodium. Conclusion: Daily intake of salt was high which increases the risk for hypertension. Comparison of methods for estimation revealed that none of the three methods could be used for estimating daily intake of salt in local settings of Pakistan.

This data note describes the linked antenatal and delivery records of the mothers and index children of the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort study. These records were extracted from the computerised maternity record system ‘STORK’ used by the two largest NHS trusts in the study catchment area. The STORK database was designed to be populated by midwives and other health professionals during a woman’s pregnancy and shortly after the baby’s birth. These early computer records were initiated in the early 1990s, shortly before the start of enrolment to ALSPAC. At this time the use of electronic medical record systems such as ‘STORK’ was very new, the accuracy of the records has been questioned and little contemporary detailed documentation is available. Small sample spot checks on the accuracy of the information in ‘STORK’ suggests extensive missingness and differences against gold-standard fieldworker abstracted information in some variables; yet high levels of completeness and agreement with gold-standard data in others. Software code was created using STATA (StataCorp LLC) to transform the original CSV (comma-separated values) files into a cohesive and consistent format which was reviewed for data-completeness for its potential use in future research. The cleaned ‘STORK’ records provide health, social and maternity data from the very earliest period of the ALSPAC study in an easily accessible format, which is particularly useful when other sources of data are missing.

Background: The study was designed to estimate daily salt intake, its discretionary use in healthy individuals and to validate three common methods for salt estimation in Pakistani population. Methods: Information on demography and discretionary salt use was collected healthy adults (>18 years) along with a blood sample, spot urine sample and 24 hours urine samples. Sodium, chloride, potassium levels and serum creatinine were measured using standard methods. For daily salt estimation, three common methods i.e. INTERSALT, Tanaka and Kawasaki were validated for their applicability in local settings. Results: Overall 24 h sodium excretion was 158 mmol/l indicating intake of 8.64 (4.43) grams salt per day which was significantly associated with male gender (p. <0.004) and adding salt during cooking (p. <0.0001). Most (73%) of the participants know about hazardous effects of high salt intake, however, only 25% consider important to lower salt intake. Although, there is insignificant difference (p. 0.09) between measured and estimated 24 hour urine however none of three methods i.e. INTERSALT(bias: -19.64; CCC -0.79), Tanaka(bias: 167.35; CCC -0.37) and Kawasaki (bias: -42.49, CCC -0.79) showed any agreement between measured and estimated 24 hour sodium. Conclusion: Daily intake of salt was high than recommended by the WHO. Findings showed that none of the three methods could be used for estimating daily intake of salt in local settings of Pakistan.

A strategy for rapid in situ elimination of interfering substances that are present in extracts of food samples during assay is described in this article. The novel feature of this method is that the sample purification is carried out as a part of the assay, and a separate sample cleanup step is not required. The assay procedure involves the sequential addition of standard or sample, cleaning solutions, and aflatoxin B1–horseradish peroxidase conjugate (AFB1-HRP) over antibody-spotted zones of a membrane, and 3,3′-diaminobenzidine was used as the substrate for visualization. We have determined that trifluoroacetic acid and propionic acids at concentrations of 100 mM are highly effective for cleaning groundnut, wheat, corn, and poultry feed samples and that NaHCO3 (100 mM) is successful in cleaning processed soybean. In all cases, subsequent washing was performed with phosphate-buffered saline solution to facilitate the removal of traces of adhering interfering substances. A batch of 12 samples can be analyzed within 8 min either by visual comparison of the color intensity (inversely related to the analyte concentration) of a sample spot with those of reference standards or, more precisely, by densitometry. The method was tested for the analysis of AFB1 in groundnut, wheat, corn, processed soybean, chili, and poultry feed. The detection limit obtained was 5 μg/kg, except for chili, where it was 10 μg/kg. The average recoveries from different noninfected food samples spiked with AFB1 at concentrations of 5 to 100 μg/kg were between 99 and 105%. The values obtained for infected corn and groundnut samples correlated well with the estimates obtained by high-pressure liquid chromatography. The absence of a sample extraction step reduces the cost and labor involved in the assay. The method may be potentially applicable to the assay of other mycotoxins and environmental pollutants.

ABSTRACTWe have utilized time-resolved high-temperature atomic force microscopy (AFM) to investigate the mechanism by which topographic templates induce alignment of cylinder-forming diblock copolymer thin films. By tracking the same sample spot during thermal annealing, we observed that the structural evolution and alignment of thin films in confinement involve an intermediate state with disordered morphology and the evolution and annihilation of disclination quadrupoles guided by the channel edges, which ultimately lead to the essentially perfect alignment of cylindrical microdomains.

Exploratory synthetic strategies may yield limited quantities of sample. Characterization of such limited-quantity samples is facilitated by the use of sensitive analytical methods and smart sample preparation. Polymers may be analyzed by mass spectrometry for molecular weight distributions, structural information (such as endgroups), and impurities. However, polymer research using mass spectrometry has not focused on detection limits; in some work the amount of polymer used is not even mentioned. Studies to determine detection limits of polymers and studies that characterize sample preparation techniques can provide valuable information.Examination of the sample surface on a probe tip, generated by the use of an aerospray technique for sample deposition, was accomplished by scanning electron microscopy (SEM). Aerospraying the polymer and matrix solutions allowed signal averaging of mass spectra from up to 400 shots on the same sample spot. SEM images showed the surface of the probe to have a fairly uniform coating of the sample and matrix.