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As announced in the May issue of Hybrid Circuits, ISHM‐Benelux is organising a one‐day conference on applications of hybrid circuit technology.

Reviews some of the chemistry and environmental hazards associated with chlorine and bromine compounds when used as water disinfectants in many industrial processes. Lays emphasis on the oxidation of bromide by chlorine to bromate, a suspected genotoxin. A risk assessment of the predicted presence is detailed. In view of the formation of haloforms and other noxious substances derived from chlorine, some of the advantages of the use of chlorine dioxide are detailed. Proposes recommendations for water regulators to consider the inclusion of bromine‐containing substances, and in particular bromate, in forthcoming legislation.

The key to the production of high quality multilayer PWBs lies in a clear understanding of the many interactions between the chemical and mechanical processing involved. This describes some of these interactions, namely those between oxide treatment, lamination and drilling and the subsequent chemical processing steps, up to, and including, copper electroplating. Choice of oxide treatment has consequences that are not limited to the lamination and drilling operations. Process problems, such as ‘pink ring (haloing)’ are discussed in the context of their sensitivity to particular stages in the manufacturing process.

The results of human studies evaluating the efficacy of plant Phytosterols on liver function were inconsistent. Therefore, the purpose of this paper is to eliminate these controversies about the Phytosterols consumption on liver serum biochemistry in adult subjects.

The literatures systematically searched throughout PubMed and Scopus databases up to June 2018; it was conducted by using related keywords. Estimates of effect sizes were expressed based on weighted mean difference (WMD) and 95% CI from the random-effects model (erSimonian and Laird method). Heterogeneity across studies was assessed by using I2 index. Eighteen studies reported the effects of Phytosterols (PS) supplementation on liver serum biochemistry.

The current meta-analysis did not show a significant effect on ALT (MD: 0.165 U/L, 95% CI: −1.25, 1.58, p = 0.820), AST (MD: −0.375 IU/Liter, 95% CI: −1.362, 0.612, p = 0.457), ALP (MD: 0.804 cm, 95% CI: −1.757, 3.366, p = 0.538), GGT (MD: 0.431 U/L, 95% CI: −1.803, 2.665, p = 0.706) and LDH (MD: 0.619 U/L, 95% CI: −4.040, 5.277, p = 0.795) following PS consumption.

The authors found that no protective or toxic effects occur after the consumption of Phytosterols on liver enzymes including ALT, AST, ALP, LDH and GGT.

The compatibility of available AIN substrate materials with thin film metallisation processes is briefly discussed. The AIN material is shown to be covered with a very thin oxide layer. NiCr and NiCr‐Ni‐Au layers have been deposited onto the substrates; the adhesion between these layers and the ceramic is tested. In the substrate, via‐holes have been made by laser drilling, and the influences of the ambient gas atmosphere on the creation of such via‐holes have been observed. Advantages and limitations of the different methods of producing via‐holes that can be metallised are discussed. A high density hybrid circuit module on AIN is demonstrated.

The advent of novel advanced packaging technologies such as multilayer thin‐film interconnect, combined with continuous improvements in IC clock speed and circuit performance, has placed extreme demands on electronics packaging and package materials. Aluminium nitride (AIN) ceramic offers significant opportunities and advantages for package design, particularly where the effective thermal management and overall reliability of large devices are a high priority. AIN has already been successfully employed at the substrate level for the enhanced thermal relief of power devices. Examples of these applications include heat sinks and device mounts for thyristor modules, power transistors, solid state relays, power SCRs, switching modules, LEDs and various RF package configurations. Both bare and metallised AIN substrates are beginning to find application as a substitute for beryllia (BeO) in mass market and high reliability automotive electronics applications. Successfully implementing AIN in a high level electronics packaging application requires a systems approach in which the intrinsic properties of AIN are considered as ‘first principles’ in shaping the package design process. The unique physicochemical and mechanical properties of AIN require the development of specialised metallisation and co‐firing processes to fabricate the advanced components necessary for hermetic packaging of complex devices and multichip modules. This paper presents a practical and mass manufacturable AIN‐based package tailored to these high level applications. The package design is unique in that it provides for the total separation of the electrical‐signal conduction from the mechanical support/mounting functions of the package. Such a separation of the functions improves both the package durability and reliability relative to currently available electronics packages of conventional designs.

Seaweeds are known accumulators of trace elements and edible seaweeds are popular commodities in health food outlets. This particular study covered an area directly affected by discharges from the Dounreay and Sellafield nuclear plants. The results indicate that radionuclide activity levels in Scottish edible seaweeds are low but are marginally high on the north‐west coast than the north‐east. Natural radionuclides are about two orders of magnitude more abundant than those from the nuclear industry. Comparisons were made with Japanese seaweeds: activities were within the same range.

The purpose of this paper is to establish historic regulatory conditions and priority national characteristics eliciting outstanding best practices in clinical trial regulatory systems, towards global health objectives through targeted economic development.

Exploratory review of clinical trial processes of three industrialized nations with similar democratic processes – Japan, the UK and the USA – in order to determine the efficacy of international clinical trials.

Outstanding best practices in national vaccine clinical trials can guide the international economic development, manufacturing and distribution policy strategies necessary to form the basis of a cross‐cultural global delivery system.

This study's contribution to academic literature is threefold: first, it reviews established fundamental clinical trial processes for Japan, the UK and the USA; second, it distinguishes similarities and differences to determine best practices; and third, it suggests changes in regulatory vaccine clinical trials towards achieving global health objectives.

The purpose of this paper is to use alternative polymerisation methods, i.e. UV irradiation to synthesise poly(acrylamide)/montmorillonite nanocomposite and characterise the composite.

Polymer/montmorillonite nanocomposite was synthesised by the polymerisation, induced by UV radiation and the structure of the composite was studied by means of FTIR, NMR(¹³ C, ²⁷Al and ²⁹Si) and X‐ray diffraction.

The poly(acrylamide)/montmorillonite nanocomposite was synthesised by UV irradiation, and its structures showed that the acrylamide was intercalated in the lamina of montmorillonite in bimolecular layers. FTIR and NMR analyses showed that there was no major chemical change of the polymer chain associated with the intercalation. The interaction between montmorillonite and polymer was mainly related with the van der Waals forces and hydrogen bonding, not with the bonding involved with the carbon atoms.

There are few reports on the synthesis and characterisation of polymer/montmorillonite composite prepared with UV radiation.

The alternative synthesis method using UV irradiation can provide a new way for the preparation of montmorillonite/acrylamide nanocomposite for the application in moisture and organic solvent vapour sensors, etc.

This provides a way for the synthesis of polymer/montmorillonite nanocomposite using polymerisation induced by UV radiation, which can be used in the thin membrane preparation for sensor and special application. Characterisation of the material revealed the structure of the nanocomposite, which would be helpful for the study of structure design and property improvement.

The possible causes of inner layer junction cracks on multilayer PCBs are discussed and the problems that cracks can cause under rework conditions. The procedure to identify the cracks and their exact location within and around the electroless copper junction is shown, along with guidelines on the possible ways to eliminate the cracking problem and on testing procedures to ensure a reliable product.