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Translocation is an important conservation tool for reducing the probability of extinction of threatened plants. It is also becoming an increasingly common management practice, as habitats are destroyed and climate change pushes more plants beyond the limits of their tolerances. Here we outline the case for informing translocations with dedicated genomic data. We begin by describing principles for using genomic and genetic approaches to enhance the efficiency and success of translocation actions. This includes ensuring that translocated populations are adaptively representative, diverse, and composed (to the greatest possible extent) of unrelated individuals. We then use two Australian case studies to illustrate how these principles have been applied in practice and in a resource-efficient way. For Prostanthera densa, we describe how genomic data have quantitatively informed complex decisions, such as whether, and how extensively, to mix individuals from spatially isolated populations in translocated populations. For Fontainea oraria, genomic data have been used during post-translocation monitoring to confirm that newly established populations incorporate and recombine the little diversity that remained in wild individuals. Overall, we illustrate how a simple workflow can support the development and planning of genomic studies and translocation activities in tandem. In order to ensure greater adoption of translocation genomic workflows, funding bodies in charge of biodiversity management and conservation must direct the necessary resources towards them.

Leaf size varies within and between species, and previous work has linked this variation to the environment and evolutionary history separately. However, many previous studies fail to interlink both factors and are often data limited. To address this, our study developed a new workflow using machine learning to automate the extraction of leaf traits (leaf area, largest in-circle area and leaf curvature) from herbarium collections of Australian eucalypts (Eucalyptus, Angophora and Corymbia). Our dataset included 136,599 measurements, expanding existing data on this taxon’s leaf area by roughly 50-fold. With this dataset, we were able to confirm global positive relationships between leaf area and mean annual temperature and precipitation. Furthermore, we linked this trait-climate relationship to phylogeny, revealing large variation at the within-species level, potentially due to gene flow suppressing local adaptation. At deeper phylogenetic levels, the relationship strengthens and the slope converges towards the overall eucalypt slope, suggesting that the effect of gene flow relaxes just above the species level. The strengthening of trait-climate correlations just beyond the intraspecific level may represent a widespread phenomenon across various traits and taxa. Future studies may unveil these relationships with the larger sample sizes of new trait datasets generated through machine learning.

Board-level drop test performance was evaluated and compared for the following four different solder combinations in BGA/CSP assembly: 1) SnPb paste with SnPb balls, 2) SnPb paste with SAC105Ti balls, 3) SAC305 paste with SAC105Ti balls, and 4) SAC305 paste with SAC105 balls. Presence of Ti improved the drop test performance significantly, despite the voiding side effect caused by its oxidation tendency. It is anticipated that the voiding can be prevented with the development of a more oxidation resistant flux. The consistently poor drop test performance of 105Ti/SnPb is caused by the wide pasty range resulted from mixing SAC105 with Sn63 solder paste. The effect of Ti in this system is overshadowed by the high voiding outcome due to this wide pasty range material. In view of this, use of SAC105 BGA with SnPb solder paste is not recommended, with or without Ti addition. High reflow temperature drove fracture shift to interface at package side, presumably through building up IMC thickness beyond the threshold value. A lower reflow temperature is recommended. Electrical response is consistent with complete fracture data. But, complete fracture trend is inconsistent with that of partial fracture trend, and neither data can provide a full understanding about the failure mode. By integrating complete fracture and partial fracture into “Virtual Fracture”, the failure mechanism becomes obvious and data sets become consistent with each other.

A series of polymer alloys based on different compositions of Nylon 6,6 oligomers (NYL66Oґs) and epoxy resin have been prepared. The oligomer was extracted from the waste residues of the industrial production of nylon 6,6 and was dissolved in the epoxy resin. The mixture was crosslinked at 333 K using dodecenylsuccinic anhydre (DDSA) as a curing agent. The tensile strength and flexural modulus were found to increase with the addition of NYLO66O up to a maximum value of 2 wt % oligomer content. Both, the tensile and impact strength show a maximum increase due to the addition of 35 wt % NYLO66O. The compressive strength testing revealed a considerable increase, up to 87 %, over that of the neat epoxy with the addition of 1 wt % NYLO66O. An interesting relationship between the mechanical properties and the developed morphology of the blends has been found.

Assembled BGA/CSP devices with SnAgCu (SAC) solder joints are vulnerable when dropped due to the fragility of solder joints. Although reducing the Ag content of SAC alloy does help, the crack resistance when dropped is still considerably poorer than the eutectic SnPb system. Therefore a new alloy with improved drop test performance is greatly desired. In this work, SAC105 doped with Ti (SAC105Ti) as a BGA/CSP sphere was studied for its drop test reliability. Four different solder combinations were evaluated: 1) SnPb solder paste with SnPb balls, 2) SnPb solder paste with SAC105Ti balls, 3) SAC305 solder paste with SAC105Ti balls, and 4) SAC305 solder paste with SAC105 balls. The number of completely fractured interconnects was counted for each type of component after a total of 100 drops. The cell with the fewest number of fractured joints was the pure SnPb cell, followed closely by SAC305 solder paste/SAC105Ti ball, then SAC305 solder paste/ SAC105 ball and lastly SnPb solder paste/SAC105Ti ball. This trend is consistent with the trend observed by measuring the electrical resistance. The combination of SAC305 solder paste with SAC105Ti balls was the best solder joint structure tested in terms of the lowest number of partial interconnect fractures and outperformed the other three combinations.

In this paper, a study of the source of contamination for ST and SC connectors and the influence of the contamination on the optical performance was studied. The PVC protective dust cap was confirmed as the primary source of contamination. The contaminants found on the inner surface of the dust cap correlated to that found on the end face of the connectors. Contamination is readily transferred to the optical surfaces of the connector by deforming the PVC cap when it is push-fitted onto the connector. The PVC cap has been replaced with a hard, polyethylene dust cap, resulting in improved quality of the incoming parts up to 80-85%. This was further improved by using a polyethylene non-contact duct cap. The influence of contamination and scratches on BER was studied and we can conclude that the BER results strongly depended upon different levels of contamination and scratches. This and other issues will be subject to further research.

The contamination of fiber optics connectors has recently been recognized as an industry wide problem. The contamination has resulted in degradation of optical signal performance, which creates false fails during the manufacturing process. These contaminated fiber optics connectors require additional manufacturing operations such as inspection of incoming components, cleaning process and re-inspection. The cleanliness of test connectors is also very important to ensure good product quality. The dirty connectors in the test environment create false functional failures at the board level, resulting in unnecessary and costly rework. All precautions have to be taken to identify the critical steps in the manufacturing process that cause the contamination to the component, assembly or board levels. The potential sources of contamination and the mechanisms of the transferring contamination have been analyzed.