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© 2015 The Authors. Journal of Chemical Technology & Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Instead of reacting B and Mg powders, MgB4 was used as precursor to react with Mg to obtain the polycrystalline samples of nominal composition MgxB2 (x = 1.2, 1.5, and 1.7). Upon increasing the sintering temperature to 750 °C, the reaction between MgB4 and Mg was thermodynamically intensified leading to the formation of larger MgB2 weight fraction as estimated from X-ray diffraction (XRD) data using the Rietveld method. Despite no further improvement to the weight fraction of this phase by increasing the excess nominal Mg, it was shown that the critical current density (Jc) was enhanced by almost one order of magnitude. At 5 K, 2 T, Jc for the sample Mg1.5B2 is estimated to be 4.5 × 105 A cm−2. The enhancement of Jc is attributed to the collective effect of improved grain connectivity and flux pinning by unreacted Mg. Incorporation of nano-SiC for reaction resulted in a more gradual drop of Jc with applied magnetic field. Hence, Jc can be tailored to meet the range of fields intended for various applications via optimization of excess nominal Mg and dopant additions.

Aim: To evaluate the reliability of transcutaneous bilirubinometry (TcB) during and after phototherapy. Methods: TcB was performed on the forehead and chest of infants with neonatal jaundice when capillary blood was sampled for bilirubin determination in a control group of 240 neonates. In a second group of 70 neonates exposed to phototherapy the same procedure was performed after at least 24 h of exposure; on the forehead, TcB was done in the centre of the unexposed area and also on the adjacent exposed area, and the exposed chest. During the post-phototherapy period, TcB was again done during the first and second days, at least 18–24 h after cessation of phototherapy. The results were then statistically evaluated and regression curves were plotted. Results: A close correlation between TcB values and bilirubin levels was observed in the control group. In the phototherapy group, a correlation was also found between the TcB and the bilirubin values, but this correlation was significantly poorer than that of the controls; the correlation for the covered part of the forehead was significantly better than that of the exposed part but still poorer than that of the controls, though the difference was no longer significant. Skin colour recovered during the post-phototherapy period and correlation was better than that during exposure and no longer significantly different from that of the controls. Conclusion: Through its bleaching effect on the skin, phototherapy affects the correlation between TcB and the bilirubin values, but does not totally eliminate it. The unexposed parts show a better correlation, though this was still poorer than that of the controls. Recovery of skin colour occurred within 18–24 h after cessation of exposure.

The initial oxidation of Co86Cr14 and its constituent metals is investigated using an in situ dynamic secondary ion mass spectrometry (SIMS) technique. Simultaneous analysis and controlled formatio ...

The effect of γ-ray irradation on the emeraldine (EM) base form of polyaniline was investigated. The process of γ-ray, UV, and thermally-induced graft copolymerization of EM base with acrylic acid (AAc) in a number of solvents and co-solvents were compared in an attempt to prepare a water-solube EM through N-acylation. The presence of N-acylation was investigated by thermogravimetric (TG) analysis, Fourrier transform infrared (FTIR) spectroscopy., and X-ray photoelectron spectroscopy (XPS). In all cases, the grapht concentration and the resulting surface conductivity were shown to be a function of the monomer concentration. The thermostability and weight loss behavior of the grapht-copolymerized EM included those that were characteristic of the EM base, the AAc polymer and the amide polymer. Some of the grapht-modified EM base samples exhibited good water solubility. In particular, the γ-ray-induced graft copolimerization of EM with AAc in N-methyl-2-pyrrolodinone (NMP)/water co-solvent readily gave rise to a water soluble, self-protonated and semi-conductive EM, which could be cast into free-standing films from an aqueous solution.

The modification of argon plasma-pretreated single-crystal Si(100) wafer surfaces via the UV-induced graft polymerization of poly(ethylene glycol) methacrylate (PEGMA) macromonomer (molecular weight ∼ 340) for biomaterials applications was explored. The modified Si(100) surfaces were characterized by X-ray photoelectron spectroscopy and atomic force microscopy. Surface peroxide concentrations resulting from the argon plasma treatment and subsequent atmospheric exposure were determined by a coupling reaction with diphenylpicrylhydrazyl. The results suggested that a short plasma treatment time of 10 s and brief air exposure were sufficient for generating an optimum amount of peroxides and hydroperoxides for the subsequent UV-induced graft polymerization. The graft concentration of the PEGMA polymer increased with increasing PEGMA macromonomer concentration for the graft polymerization and with increasing UV graft polymerization time. The PEGMA graft-polymerized silicon surface with a high poly(ethylene glycol) graft concentration was very effective in preventing protein adsorption and platelet adhesion. The grafted PEGMA polymer layer on the Si(100) surface exhibited fairly good stability during storage in a buffer solution. © 2001 John Wiley & Sons, Inc. J Biomed Mater Res 56: 324–332, 2001

X-ray photoelectron spectroscopy (XPS) was employed for the study of the physicochemical interactions at electrode/polymer interfaces involving metals of high and low work functions and thin films of poly(p-phenylene vinylene) (PPV) and poly[2-methoxy-5-(2'-ethyl-hexyloxy)-1,4-phenylene vinylene] (MEH-PPV). The changes in the C 1s core-level line shape of the polymers, the evolution of the metal core-level spectra and the changes in chemical compositions at the interfaces involving polymer coated on indium-tin oxide (ITO), sputtered ITO on polymer, and in situ evaporated magnesium (Mg) on polymer were carefully monitored. Indium of the ITO in both the ITO/polymer and polymer/ITO assemblies was found to diffuse towards the polymer at the interface. Oxygen migration was also observed at the ITO/polymer interfaces. The results obtained from in situ analysis by angle-resolved XPS of the interactions between thermally evaporated Mg and PPV and Mg and MEH-PPV indicated the formation of an interfacial layer in each case. The surface diffusion of adsorbed oxygen from the bulk of the conjugated polymer film played a dominant role in the interfacial reactions. The interfacial layer consisted of Mg oxides, Mg clusters, Mg metal and Mg-polymer complexes.

This paper presents resistivity data for a range of surface-grafted and copolymerized polymers and some challenges yet to be faced in resolving the effects of surface modification on their surface properties, in particular on electrical resistivity in their surface regions. The principal substrates used for measurement were polyaniline (PAN), low-density polyethylene (LDPE) and polytetrafluorethylene (PTFE). Electrical resistivity has been determined as a function of graft monomer type (acrylic acid, sodium salt of styrene sulphonic acid and N,N-dimethylacrylamide), graft temperature, grafting time and plasma pretreatment time. In the case of grafted PTFE, the effect of an emeraldine coating on resistivity is also determined.

Bimetallic Pt-Co and monometallic Pt and Co catalysts in as-prepared and reduced states were characterized by X-ray diffraction, temperature-programmed reduction, XPS and Fourier transform infrared spectroscopy (FTIR). Temperature-programmed reduction and XPS results showed that the addition of platinum lowered the reduction temperature of cobalt oxides and simultaneously increased the amount of cobalt surface phase. The metallic Pt and Co in bimetallic Pt-Co catalysts was found to be highly dispersed in supports. In situ FTIR study of CO adsorption on catalysts confirmed that there was either strong interaction between metallic Pt and Co, or a Pt-Co bimetallic interphase was formed. The CO 2 reforming of methane to synthesis gas was also investigated. Both Pt and Co in Pt-Co bimetallic catalysts exerted catalytic activity on CO 2 reforming of methane. The coking was effectively inhibited over Pt-Co bimetallic catalysts, which was attributed to the formation of a Pt-Co bimetallic interphase and the increase of cobalt surface phase.

OBJECTIVE To study the effect of phototherapy for neonatal hyperbilirubinaemia on thyroid function as neonatal thyroid screening is sometimes performed during exposure to phototherapy. METHODOLOGY Infants with non-haemolytic hyperbilirubinaemia were sequentially allocated to fibre-optic phototherapy, conventional daylight phototherapy, or a combination of both. Bilirubin concentration was monitored 12 hourly by capillary blood sampling; venous blood was sampled for thyroid stimulating hormone (TSH) and free thyroxine (fT4) determinations, at start of exposure, at 24 h, end of exposure and 1 day later. Comparable unexposed infants served as controls. RESULTS All 123 study infants and 25 controls remained well during the study. Bilirubin levels declined during phototherapy, being most rapid in the combination group. The TSH and fT4 values at start of exposure were 3.86 +/- 0.41 mU/L (mean +/- SEM) and 33.20 +/- 1.16 pmol/L, respectively, in the fibre-optic group, 3.62 +/- 0.38 mU/L and 37.22 +/- 1.76 pmol/L in the daylight group, and 4.40 +/- 0.48 mU/L and 29.91 +/- 1.13 pmol/L in the combined group, compared with 5.77 +/- 0.40 mU/L and 34.46 +/- 1.68 pmol/L in the control group. The TSH and fT4 values declined with increasing age in the phototherapy and control groups with end of exposure values of 2.90 +/- 0.28 mU/L and 27.71 +/- 0.71 pmol/L, 2.77 +/- 0.31 mU/L and 33.52 +/- 1.22 pmol/L, and 3.44 +/- 0.30 mU/L and 27.54 +/- 0.88 pmol/L, respectively, compared with 4.21 +/- 0.61 mU/L and 27.19 +/- 2.33 pmol/L (at 72 h) in the control group. The pattern of TSH and fT4 decline in the exposed and control groups was similar, being related to increasing age. CONCLUSIONS The validity of neonatal thyroid screening is not affected by fibre-optic or conventional phototherapy or by both combined.

The objective of this study was to investigate the correlation of transcutaneous bilirubinometry (TcB) and plasma bilirubin concentrations in full-term Chinese, Malay and Indian infants. TcB was performed with the Minolta Airshields bilirubinometer on Chinese, Malay and Indian full-term infants. The readings were taken on the chest (sternum) and forehead (glabella) when capillary blood was sampled for bilirubin determination. Five hundred and forty TcB indices in 253 Chinese infants, 282 in 169 Malay infants, and 182 in 120 Indian infants were obtained over the sternum and forehead. A good correlation between the TcB indices and the bilirubin concentrations was observed in Chinese, Malay and Indian infants : r = 0.78 (chest), r = 0.73 (forehead) ; r = 0.86 (chest), r = 0.84 (forehead) ; and r = 0.84 (chest), r = 0.82 (forehead). The correlation was just as good when the combined values were evaluated together : r = 0.80 (chest) r = 0.75 (forehead). In Chinese infants, correlation at values below 250 μmol l -1 was significantly better than that at values over 250 μmol -1 r = 0.80 versus r = -0.20, p < 0.00001 (chest), and r = 0.74 versus r = 0.07, p < 0.00001 (forehead). However, a safer cut-off point clinically would be 200 μmol l -1 , since only relatively few higher bilirubin values were encountered when TcB indices were below 200 μmol l -1 . The same pattern was noticed with the other two groups, and the combined group. Thus, TcB provides a non-invasive, cost-effective screening method for significant neonatal jaundice, sparing infants and parents physical and emotional stress, and medical and nursing personnel extra work and inconvenience.

A 3-year study (Jan. 1986-Dec. 1988) in the Kandang Kerbau Hospital revealed 678 infants with birth defects in 44,842 livebirths, (15.13 per 1,000 live births, 95% confidence intervals, CI 14.0–16.2). There were 161 cases with musculoskeletal abnormalities (3.5 per 1,000, 95% CI 3.06-4.19), 111 gastrointestinal system malformations (2.47 per 1,000, 95% CI 2.04-2.58), 88 chromosomal abnormalities (1.96 per 1,000, 95% CI 1.57-2.42), 78 cardiovascular system abnormalities (1.74 per 1,000, 95% CI 1.38-2.17), 73 urogenital system defects (1.63 per 1,000, 95% CI 1.28-2.05), and 52 central nervous system defects (1.16 per 1,000, 95% CI 0.87-1.52). The prevalence of cleft lip, cleft palate, and cleft lip/palate was 1.72 per 1,000, and Down's Syndrome 1 in 700. At review, six weeks later, the false positive rate was 4% in the infants with defects, and in the group of 709 normal controls (matched by race, maternal age, ward class and time/date of birth), the false negative rate was 0.84%. The strongest risk factors were a family history of birth defects (odds ratio, OR 3.3, 95% CI 1.8-6.4), and previous abnormal sibling(s) (OR 2.4, 95% CI 1.1–5.3). Other risk factors included drug intake during pregnancy (OR 1.2, 95% CI 0.8-2.0), becoming significant with ingestion during the first trimester (OR 1.4, 95% CI 1.1-1.8). Traditional medicine (mainly Chinese herbs during pregnancy) had a slightly higher risk (OR 1.4, 95% CI 1.0–2.0). The National University Hospital keeps a register of birth defects; trained nurses interview all mothers using a set questionnaire. Evaluation of 11,460 livebirths over a 3-year period (1991–1993) revealed 472 cases (41.19 per 1,000 livebirths, 95% CI 37.48-44.90) with 171 musculoskeletal defects (14.92 per 1,000 livebirths, 95% CI 12.69-17.16), 105 cardiovascular defects (9.16 per 1,000, 95% CI 7.41-10.91), 64 urogenital defects (5.58 per 1,000, 95% CI 4.22-6.95), 30 gastrointestinal defects (2.62 per 1000, 95% CI 1.68-3.55), 35 mixed system defects (3.06 per 1,000, 95% CI 2.04-4.07), and 18 chromosomal abnormalities (1.57 per 1,000, 95% CI 0.85-2.30). The prevalence of cleft lip/cleft lip and palate was 1.48 per 1,000. This higher prevalence could be due to the present practice of routine screening of every infant on the first day of life, together with a careful assessment for musculoskeletal defects, especially congenital dislocation of the hips.

The catalytic and structural properties of two different preparations of manganese oxide supported on high surface area zirconia are compared. The catalyst were prepared by grafting from an alkoxide precursor and by conventional aqueous wet impregnation technique. Reaction of manganese ethoxide with the hydroxyl groups at the surface of the zirconia support is highly specific and allows manganese oxide to be deposited layer by layer. The zirconia used in this study has a mesoporous structure; pores with diameters ≦ 5.8 nm were found to be inaccessible to the manganese ethoxide precursor. Hence, only about half of the total surface area is available for the reaction with ethoxide. A quantitative evaluation of the XPS intensities for manganese and zirconia shows that about 2.5 layers of manganate are deposited after five grafting steps. Activity tests made on these catalysts confirm the monolayer buildup. The specific activity of the isolated manganese ions which result from the first grafting step is very low; the specific activity increases by an order of magnitude once the first monolayer is completed, and shows a further increase in the second and third layers. In contrast, impregnation with manganese acetate results in small manganate crystallites, which most likely form inside the pores. The specific activity of these catalysts and their selectivity towards acetone in isopropanol decomposition are very similar to that of bulk manganese dioxide whereas the grafted samples show a high selectivity towards propene.

Manganese oxide deposited on alumina and magnesia by different preparation methods has been studied with respect to its surface structure and reactivity. The controlled deposition of mono-atomic layers is effected by a grafting reaction between surface hydroxyl groups and manganese ethoxide. Repeated grafting allows multiple layers to be built up in a controlled manner. The properties of these catalysts differ from those prepared by conventional wet impregnation techniques and mechanical mixing. Test reactions involving carbon monoxide oxidation and isopropanol decomposition reveal significant differences in the activity and selectivity of the catalysts prepared by grafting, impregnation and mechanical mixing. The manganese oxide grafted to alumina shows bulk-like properties after a full monolayer is built up. XPS studies show that the grafting reaction leads to continuous films of the manganate covering the entire surface with monolayer thickness, whereas impregnation most likely results in small crystallites which cover only part of the surface. The calcination temperature is an important parameter determining the oxidation state of the manganese and the crystallinity of the oxide. Ammonia and isopropanol temperature-programmed desorption indicates that the acid/base and redox properties of the catalysts are considerably modified by a strong interaction between the support and the overlayer.

A calculation method for the secondary ion mass spectrometry (SIMS) analysis of the reaction of a pure metal with gas mixtures of water and oxygen is introduced. Equation systems are to be solved, each expressed as: Y=A×X, where Y is an amplitude column measured from the SIMS spectrum, A is a matrix constructed from the relative abundances of isotopes of the metal and X is an unknown amplitude column of the relevant species Me a OH b ± (a=1, 2; b=0, 1, 2 and 3)

Summary An investigation was made into the onset and severity of neonatal jaundice in 114 patients following spontaneous labour and labour induced by (a) amniotomy, (b) amniotomy and simultaneous infusion of oxytocin, (c) amniotomy and simultaneous administration of oral prostaglandin E2, (PGE2,). No significant difference in serum bilirubin levels in the first five days of life was found in the four groups.

Phototherapy with either daylight or blue lamps resulted in the development of the bronze baby syndrome in 13 infants. 'Thermotherapy' with an incandescent bulb emitting light mainly in wavelengths not effective for phototherapy caused this syndrome in the 14th infant with respiratory failure. Hepatic dysfunction was present in all infants. The infants were well in spite of the bronzing, after their initial condition had improved. Bronzing disappeared within two months in all but one infant; in eight infants with regular blood examination, the hepatic function became normal by ten months of age, but spectroscopy demonstrated the presence of the pigment(s) even at one year. Normal development was observed.

The effect of exchange transfusion with ACD blood on electrolyte levels was studied in 60 exchanges performed on 57 infants. The blood levels of potassium, sodium and chloride in donor blood were markedly different from those in the infants. The effect of the exchange procedure on the electrolyte levels in the infants was, however, relatively small and rapidly reversed after the exchange. ACD blood not exceeding 5 days old seems to have little effect on the infants' electrolyte levels during exchange transfusion.

The pathology of four types of chondrodysplasias, viz., type II achondrogenesis, thanatophoric dwarfism, Saldino-Noonan syndrome, and chondrodysplasia punctata were studied. In each of these disorders, cells with features similar to the chief and dark chondrocytes of normal hyaline cartilage were seen to be altered in different ways. There was a total absence of chief cells in type II achondrogenesis. All the chondrocytes present were of one variety at different states of maturation, with the fully matured cell having features of dark chondrocytes. The absence of chief cells was associated with marked diminution of interlacunar matrix and failure of growth plate development. The chief chondrocytes in thanatophoric dwarfism appeared diminished in number. They were probably abnormal functionally as evident by their lack of cytoplasmic vacuolation and the formation of thick, occasionally branched collagen in the matrix. The growth plate was stunted and poorly developed. Striking changes involving the dark cells were noted in Saldino-Noonan syndrome, where unusually elongated dark cells were found in groups within abnormal cystic spaces. The chief cells were large and contained abnormal cytoplasmic filaments. There was no formation of a growth plate. In chondrodysplasia punctata, the chief cells were enlarged and abnormally vacuolated. The matrix showed excessive aggregates of coarse granular material. In addition, there were focal accumulations of highly abnormal chief and dark cells with abnormal matrix which contained increased amount of keratan sulphate and culminated in spotty calcification.

SYNOPSIS An unusual case of heteropagus is presented, in which a limb was attached to the sacral area of an otherwise apparently normal infant. A sausage-shaped mass resembling a limb is most unusual and has never been documented before. Obvious amniotic bands were also present at the point of attachment and presumably contributed to the constriction at this area. Progress was normal after removal of this appendage.

A brain tissue embolus was observed in a major pulmonary artery in the right lung, in a neonate who died from intracranial haemorhage 36 hours after delivery. This is the fifth documented case in a neonate and the only one in whom survival had occurred beyond one hour. Brain tissue emboli in the pulmonary circulation occur very rarely; it has been described in adults and children with head injuries. In newborn infants with severe congenital malformations of the central nervous system, brain tissue has been found growing in the lungs; the possibility of this being the result of prenatal brain trauma with embolization has been raised. In newborn infants, pulmonary brain tissue embolism as a result of birth trauma has been reported only very rarely; as far as the authors are aware, only four such cases have been documented. In view of the rarity of this condition, it was thought that the present case merited reporting.

Transcutaneous bilirubinometry using the Minolta Airshield TcB was performed on 40 preterm VLBW Chinese infants during the first 7 days of life; altogether 614 observations were made on the forehead and sternum, respectively. A positive correlation between the TcB index and plasma bilirubin concentration was obtained on the forehead and sternum. Positive plasma bilirubin-TcB index correlations were also observed for each individual day. The plasma bilirubin-TcB index (forehead) regressions were fairly similar for the individual days and the combined overall regression except for 2 days (days 5 and 7). A slight improvement was observed when only bilirubin concentrations less than or equal to 200 mumol/l were evaluated. The intercepts were however different for individual days requiring correction factors to the combined overall regression intercept if the regression is to be used for the respective days. However, the plasma bilirubin-TcB index (sternum) regression for the individual days were significantly different one from another, and from the overall combined plasma bilirubin-TcB index (sternum) regression. This significant difference was still observed when only plasma bilirubin concentrations less than or equal to 200 mumol/l were evaluated. Hence, transcutaneous bilirubinometry has major limitations in preterm VLBW infants.

Tan, K. L. (1976). Aust. paediat. J. 12, 43–46. Phototherapy for neonatal jaundice in Chinese, Malay and Indian infants. The effectiveness of phototherapy for neonatal jaundice was compared in three closely matched groups of Chinese, Malay and Indian infants. Reduction in bilirubin levels was achieved in all three groups, and no significant difference was demonstrated among them. Phototherapy appears to be equally effective in reducing bilirubin levels in Chinese, Malay and Indian infants.

Synopsis Osteogenesis imperfecta congenita is a very rare condition. Among 184,311 deliveries over a 5 year period (1965–1969) there were encountered only 3 cases which demonstrated varying degrees of severity of the condition. The incidence, pathological and genetic bases, diagnosis and management of osteogenesis imperfecta congenita are discussed.

Summary One thousand, nine hundred and thirty apparently normal newborn infants were examined for the presence of the third fontanelle. In addition other newborn infants with abnormalities were also screened for the same defect. The incidence of the third fontanelle was high, in this study, among the normals, compared with past studies. The incidence seemed highest in the group weighing 2 001 to 2 500 g. In the abnormal group, the incidence was very significantly raised in infants suffering from the congenital rubella syndrome or Down's syndrome; it was raised but not significantly in infants presenting with various other abnormalities. The presence of the third fontanelle should alert the examiner to the possibility of other defects in the infant.

A study evaluating the influence of gestational age and birth weight on the infant response to phototherapy for neonatal jaundice was attempted. Phototherapy was equally effective in small for dates infants and premature infants of comparable size, and also in the small for dates infants and normal full size infants of comparable gestational age. Gestational age and infant size do not seem to play a significant role in determining infant response to phototherapy.

Woon, K. Y. and Tan, K. L. (1979). Aust. Paediatr. J., 15, 275–277. Aplasia of the first and second branchial arches. A case with the very rare syndrome of otocephaly is reported. It is possible to diagnose this condition in-utero by radiography. Since this is a lethal condition, remedial action can be taken in early pregnancy.

Tan. K. L. (Department of Paediatrics, University of Singapore, Singapore). Elevation of congenital depressed fractures of the skull by the vacuum extractor. Ada Paediatr Scand 63: 562, 1974.—The vacuum extractor has been found to be effective in elevating depressed fractures of the skull, especially those of some duration. Two cases are reported to illustrate this procedure. No ill effects have been encountered.

Bilirubin levels in Chinese homozygous twins who were clinically well at delivery with no evidence of isoimmunization or the twin transfusion syndrome were studied. It was demonstrated that order of delivery, birth weight or haemoglobin level of the twins did not seem to have any significant effect on the bilirubin levels in the first week of life. The bilirubin levels were in fact similar to those of singletons. Twinning does not seem to have any significant effect on the bilirubin levels of newborn infants.

Summary : Post-haemorrhagic shock in the newborn is a relatively rare condition. If evidence of fetal bleeding during labour was not available, a baby in this condition would often be misdiagnosed as having shock due to asphyxia. Three cases of post-haemorrhagic shock are presented. The routine examination of vaginal blood shed during the first stage of labour for the presence of fetal haemoglobin is recommended. This would enable prompt obstetric action and perhaps avert fetal disaster. Careful examination of the placenta is also important and may permit the diagnosis of fetal haemorrhage soon after birth of the infant.