Missing Links, Cultural Modernity and the Dead: Anatomically Modern Humans in the Great Cave of Niah (Sarawak, Borneo)

The Great Cave of Niah in Sarawak (northern Borneo) came into the gaze of Western Science through the work of Alfred Russell Wallace, who came to Sarawak in the 1850s to search for ‘missing links’ in his pioneering studies of evolution and the natural history of Island Southeast Asia and Australasia. The work of Tom and Barbara Harrisson in the 1950s and 1960s placed the Great Cave, and particularly their key find, the ‘Deep Skull’, at the nexus of the evolving archaeological framework for the region: for decades the skull, dated in 1958 by adjacent charcoal to c.40,000 BP, was the oldest fossil of an anatomically modern human anywhere in the world and thus critical to ideas about human evolution and dispersal. Although several authorities later questioned the provenance and antiquity of the Deep Skull, renewed investigations of the Harrisson excavations since 2000 have shown that it can be attributed securely to a specific location in the Pleistocene stratigraphy, with direct U-series dating on a piece of the skull indicating an age for it of c.37,500 BP and the first evidence for associated human activity at the site going back to c.50,000 BP. The new work also indicates that the skull is part of a cultural deposit, perhaps a precursor to the long tradition in Borneo of processing of the dead and secondary burial. These indicators of cultural complexity chime with the complexity of the subsistence behaviour of the early users of the caves discussed by Philip Piper and Ryan Rabett in chapter ten of this volume.

Numerically Investigating the Effects of Cross-Links in Scaled Microchannel Heat Sinks

Thermal management as a method of heightening performance in miniaturized electronic devices using microchannel heat sinks has recently become of interest to researchers and the industry. One of the current challenges is to design heat sinks with uniform flow distribution. A number of experimental studies have been conducted to seek appropriate designs for microchannel heat sinks. However, pursuing this goal experimentally can be an expensive endeavor. The present work investigates the effect of cross-links on adiabatic two-phase flow in an array of parallel channels. It is carried out using the three dimensional mixture model from the computational fluid dynamics software, FLUENT 6.3. A straight channel and two cross-linked channel models were simulated. The cross-links were located at 1/3 and 2/3 of the channel length, and their widths were one and two times larger than the channel width. All test models had 45 parallel rectangular channels, with a hydraulic diameter of 1.59 mm. The results showed that the trend of flow distribution agrees with experimental results. A new design, with cross-links incorporated, was proposed and the results showed a significant improvement of up to 55% on flow distribution compared with the standard straight channel configuration without a penalty in the pressure drop. Further discussion about the effect of cross-links on flow distribution, flow structure, and pressure drop was also documented.

Long-term graft survival in patients with flexible open-loop anterior chamber intraocular lenses

Purpose. To evaluate the long-term graft survival in patients with flexible open-loop anterior chamber intraocular lenses (AC IOL). Methods. We retrospectively reviewed the records of patients with aphakic/pseudophakic bullous keratopathy who underwent penetrating keratoplasty and flexible open-loop AC IOL implantation in our institution from 1983 to 1988. Results. 79 eyes from 77 patients were included in the study. Mean follow-up was 50 months (range 1 to 123 months). At last follow-up 61 eyes (77.2%) had clear grafts. Among them, the visual acuity was = 20/40 in 14 eyes (23.0%), 20/50-20/100 in 22 eyes (36.1%), 20/200-20/400 in 9 eyes (14.8%) and = CF in 16 (26.2%). Increment of glaucoma medications and/or glaucoma surgery was the most frequent complication (37 eyes, 46,8%). Cystoid macular edema was newly diagnosed in 10 eyes (12.7%). Conclusions. Flexible, open-loop anterior chamber lens are a viable option in the treatment of patients with aphakic or pseudophakic bullous keratopathy undergoing penetrating keratoplasty.

Long-term graft survival in patients with flexible open-loop anterior- chamber intraocular lenses

Purpose. To evaluate the long-term graft survival and complications of flexible, open-loop anterior-chamber intraocular lenses in patients with penetrating keratoplasty for pseudophakic or aphakic bullous keratopathy. Methods. We reviewed charts of all consecutive patients who underwent penetrating keratoplasty for pseudophakic or aphakic bullous keratopathy combined with implantation of a flexible, open-loop, anterior-chamber intraocular lens at our institution between 1983 and 1988. One-hundred one eyes of 99 patients were evaluated. Graft-survival rates were calculated by using the Kaplan-Meier actuarial method. Results. Mean follow-up was 49.8 months (range. 1-144). The probability of graft survival at 1, 2, 4, 6, and 8 years was 93, 87, 78, 65, and 65%, respectively. A total of 25 (24.8%) grafts failed. Progressive corneal edema without signs of rejection was the most common finding in patients with failed grafts (10 eyes, 40%). The most frequent complication observed was newly diagnosed or worsening of preexisting glaucoma (46 eyes, 45.5%). Conclusions. Our long-term results support flexible, open-loop anterior-chamber intraocular lenses as a reasonable option, at the time of penetrating keratoplasty, in patients with pseudophakic and aphakic bullous keratopathy.

Efficacy of Biocides Used in the Modern Food Industry To Control Salmonella enterica, and Links between Biocide Tolerance and Resistance to Clinically Relevant Antimicrobial Compounds

Biocides play an essential role in limiting the spread of infectious disease. The food industry is dependent on these agents, and their increasing use is a matter for concern. Specifically, the emergence of bacteria demonstrating increased tolerance to biocides, coupled with the potential for the development of a phenotype of cross-resistance to clinically important antimicrobial compounds, needs to be assessed. In this study, we investigated the tolerance of a collection of susceptible and multidrug-resistant (MDR) Salmonella enterica strains to a panel of seven commercially available food-grade biocide formulations. We explored their abilities to adapt to these formulations and their active biocidal agents, i.e., triclosan, chlorhexidine, hydrogen peroxide, and benzalkonium chloride, after sequential rounds of in vitro selection. Finally, cross-tolerance of different categories of biocidal formulations, their active agents, and the potential for coselection of resistance to clinically important antibiotics were investigated. Six of seven food-grade biocide formulations were bactericidal at their recommended working concentrations. All showed a reduced activity against both surface-dried and biofilm cultures. A stable phenotype of tolerance to biocide formulations could not be selected. Upon exposure of Salmonella strains to an active biocidal compound, a high-level of tolerance was selected for a number of Salmonella serotypes. No cross-tolerance to the different biocidal agents or food-grade biocide formulations was observed. Most tolerant isolates displayed changes in their patterns of susceptibility to antimicrobial compounds. Food industry biocides are effective against planktonic Salmonella. When exposed to sublethal concentrations of individual active biocidal agents, tolerant isolates may emerge. This emergence was associated with changes in antimicrobial susceptibilities.

An efficient and flexible synthesis of model lignin oligomers

The use of model compounds in the development of selective lignin depolymerisation processes has been limited by the lack of complexity of these models compared with lignin itself. In this paper we report a convergent and efficient synthetic method for the flexible, multi-gram preparation of model lignin hexamers and octamers containing three of the most common connectivity motifs found within native lignin, namely ß-O-4', 5-5' and ß-5', which will be used to further the mechanistic understanding of lignin depolymerisation processes.

Clinical and experimental links between diabetes and glaucoma

Glaucoma is a leading cause of blindness. It is a multifactorial condition, the risk factors for which are increasingly well defined from large-scale epidemiological studies. One risk factor that remains controversial is the presence of diabetes. It has been proposed that diabetic eyes are at greater risk of injury from external stressors, such as elevated intraocular pressure. Alternatively, diabetes may cause ganglion cell loss, which becomes additive to a glaucomatous ganglion cell injury. Several clinical trials have considered whether a link exists between diabetes and glaucoma. In this review, we outline these studies and consider the causes for their lack of concordant findings. We also review the biochemical and cellular similarities between the two conditions. Moreover, we review the available literature that attempts to answer the question of whether the presence of diabetes increases the risk of developing glaucoma. At present, laboratory studies provide robust evidence for an association between diabetes and glaucoma.