The authors report a 39-year-old woman who presented with intermittent, excruciating nuchal and occipital headache. Magnetic resonance imaging and magnetic resonance angiography scans showed bilateral subdural haematomas with veno-occlusive disease of the superficial and deep venous systems. There were bridging collaterals with scalp veins, bleeds from which could explain the subdural haematoma. There was acute on chronic veno-occlusive disease with an acute rise in intracranial pressure and a bleed from the vein of Galen.

Mass-energy transfer across the boundaries of living systems is crucial for the maintenance of homeostasis; however, it is scarcely known how structural strength and integrity is maintained in extended phenotypes while also achieving optimum heat-mass exchange. Here we present data on strength, stability, porosity and permeability of termite mounds of a fungus-farming species, Odontotermes obesus. We demonstrate that the termite mound is a bi-layered structure with a dense, strong core and a porous shell that is constantly remodelled. its safety factor is extraordinarily high and is orders of magnitude higher than those of human constructions. the porous peripheries are analogous to the mulch layer used in agriculture and help in moisture retention crucial for the survival of fungus gardens, while also allowing adequate wind-induced ventilation of the mounds. We suggest that the architectural solutions offered by these termites have wider implications for natural and industrial building technologies. Mass-energy transfer across the boundaries of living systems is crucial for the maintenance of homeostasis 1. These boundaries can be that of an individual (human skin) 2 or a colony of individuals (swarm cluster of honeybees) 3 or that of a constructed extended phenotype (termite mounds) 4,5. The boundary conditions in these systems determine the mass and energy fluxes; therefore, the boundary must be able to respond to ambient changes. Homeostasis can be achieved, for example, by regulation of blood flow to skin 2 , or the movement of individuals between the periphery and core of a honeybee swarm 3 ; however, little is known about this transfer when the boundary consists of non-living materials, e.g. soil, as in the walls of termite mounds. Regulation becomes more challenging when the construction crew is subterranean as in fungus-farming termites with their fungus gardens 6-8. Moreover, while the external boundaries of these earthen structures must primarily be designed to respond to changes in the external environment, the internal regions need to maintain structural strength in order to prevent collapse. Termite mounds are excellent examples of biocementation and collective construction 9. Mounds can be three orders of magnitude larger than individual termites 9 and can maintain structural integrity for decades to centuries 10. Termites collect small, irregular spheres of soil, which they use for construction 9. These are analogous to bricks used in human construction, are termed 'boluses' (singular: bolus), and are made by mixing their secretions with moist soil 11. Once deposited at the construction site, boluses merge and form an almost monolithic structure resembling construction using amorphous materials such as foam. This material nature allows mound construction on irregular surfaces 9. Soil manipulation by termites imparts a tenfold increase to its strength 11. Compressive strength and density of mound soil increases from the top to the bottom of the mound due to compaction under self-weight over time 11...

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Pulmonary tuberculosis (PTB) is one of the major infectious diseases in developing countries. The objective of this study was to compare rapid diagnostics technique, GeneXpert MTB/RIF (GeneXpert) and Multiplex PCR assay (MPCR) targeting IS6110 segment and mpb64 gene for direct detection of Mycobacterium tuberculosis (MTB) in suspected PTB patients. A cross sectional study was carried among 105 sputum samples from suspected PTB patients to evaluate GeneXpert and Multiplex PCR who visited National Tuberculosis Center, Nepal. The patient's sputum samples were used directly for the GeneXpert whereas DNA extraction by CTAB method was followed to process the sample for MPCR. The sensitivity and specificity of GeneXpert and MPCR in smear positive cases was 78.6, 33.3, and 100.0%, 66.7%, respectively (P = 0.125). However, in smear negative cases sensitivity and specificity of both methods exhibited 90.9, 95.2, and 100.0%, 100.0% respectively (P = 0.625). Finally, the sensitivity and specificity of GeneXpert and MPCR were 82.9, 95.3 and 100.0%, 98.5% respectively, (P = 0.549) in pulmonary cases. Comparatively, we observed higher sensitivity and specificity for MPCR than GeneXpert for both smear positive and negative samples. Thus, we recommend MPCR alongside GeneXpert for the better diagnostic accuracy of PTB in a resource-limited country where tuberculosis is endemic.