For Whom Does the Clock Tick?: Male Repro-Temporality in Fertility Campaigns, Scientific Literature, and Commercial Accounts

Sperm swimming in circles or a lone sperm cell with two heads: male reproductive aging is increasingly equated with poor sperm quality, the prevalence of offspring learning disabilities even schizophrenia. To discuss the construction of a male biological clock, this article asks: how does the biological clock intervene in men’s reproductive bodies. And secondly: how is male repro-temporality visually and rhetorically invoked in fertility campaigns, in medical scientific accounts and in the marketing material of one elective sperm-freezing company? Situated within an interdisciplinary theoretical framework, the article draws upon biomedicalization theory (e.g. Clarke et al. 2003), reproductive masculinity studies (e.g. Daniels 2006; Almeling and Waggoner 2013), and social scientific theorizing of time and temporality (e.g. Amir 2006; van de Wiel 2014a; 2014b) to discuss the emergence of male repro-temporality. This article contributes to the interdisciplinary scholarly agenda on time and temporality by theorizing the emergence of a male biological clock as a type of repro-temporality that, in its discursive and aesthetic framing, portrays male reproductive aging as involving loss and disability. The article concludes that while the biological clock derives its temporal force from the logic of decay, it simultaneously cements heteronormative ideals of the nuclear family, re-naturalizes the genetic unit, and situates men as proactive and modern in their anticipation of future infertility.

On the Degree-Based Topological Indices of the Tickysim SpiNNaker Model

Tickysim is a clock tick-based simulator for the inter-chip interconnection network of the SpiNNaker architecture. Network devices such as arbiters, routers, and packet generators store, read, and write forward data through fixed-length FIFO buffers. At each clock tick, every component executes a “read” phase followed by a “write” phase. The structures of any finite graph which represents numerical quantities are known as topological indices. In this paper, we compute degree-based topological indices of the Tickysim SpiNNaker Model ( T S M ) sheet.

Making the clock tick: the transcriptional landscape of the plant circadian clock

Circadian clocks are molecular timekeepers that synchronise internal physiological processes with the external environment by integrating light and temperature stimuli. As in other eukaryotic organisms, circadian rhythms in plants are largely generated by an array of nuclear transcriptional regulators and associated co-regulators that are arranged into a series of interconnected molecular loops. These transcriptional regulators recruit chromatin-modifying enzymes that adjust the structure of the nucleosome to promote or inhibit DNA accessibility and thus guide transcription rates. In this review, we discuss the recent advances made in understanding the architecture of the Arabidopsis oscillator and the chromatin dynamics that regulate the generation of rhythmic patterns of gene expression within the circadian clock.

Ground-based optical atomic clocks as a tool to monitor vertical surface motion

According to general relativity, a clock experiencing a shift in the gravitational potential ΔU will measure a frequency change given by Δf/f ≈ ΔU/c2. The best clocks are optical clocks. After about 7 hr of integration they reach stabilities of Δf/f ∼ 10−18 and can be used to detect changes in the gravitational potential that correspond to vertical displacements of the centimetre level. At this level of performance, ground-based atomic clock networks emerge as a tool that is complementary to existing technology for monitoring a wide range of geophysical processes by directly measuring changes in the gravitational potential. Vertical changes of the clock's position due to magmatic, post-seismic or tidal deformations can result in measurable variations in the clock tick rate. We illustrate the geopotential change arising due to an inflating magma chamber using the Mogi model and apply it to the Etna volcano. Its effect on an observer on the Earth's surface can be divided into two different terms: one purely due to uplift (free-air gradient) and one due to the redistribution of matter. Thus, with the centimetre-level precision of current clocks it is already possible to monitor volcanoes. The matter redistribution term is estimated to be 3 orders of magnitude smaller than the uplift term. Additionally, clocks can be compared over distances of thousands of kilometres over short periods of time, which improves our ability to monitor periodic effects with long wavelength like the solid Earth tide.