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The sensing of gravity has emerged as a tool in geophysics applications such as engineering and climate research1–3, including the monitoring of temporal variations in aquifers4 and geodesy5. However, it is impractical to use gravity cartography to resolve metre-scale underground features because of the long measurement times needed for the removal of vibrational noise6. Here we overcome this limitation by realizing a practical quantum gravity gradient sensor. Our design suppresses the effects of micro-seismic and laser noise, thermal and magnetic field variations, and instrument tilt. The instrument achieves a statistical uncertainty of 20 E (1 E = 10−9 s−2) and is used to perform a 0.5-metre-spatial-resolution survey across an 8.5-metre-long line, detecting a 2-metre tunnel with a signal-to-noise ratio of 8. Using a Bayesian inference method, we determine the centre to ±0.19 metres horizontally and the centre depth as (1.89 −0.59/+2.3) metres. The removal of vibrational noise enables improvements in instrument performance to directly translate into reduced measurement time in mapping. The sensor parameters are compatible with applications in mapping aquifers and evaluating impacts on the water table7, archaeology8–11, determination of soil properties12 and water content13, and reducing the risk of unforeseen ground conditions in the construction of critical energy, transport and utilities infrastructure14, providing a new window into the underground.

Erectile dysfunction (ED) is a common condition encountered by an array of subspecialists and is the most cited research topic within the field of andrology. This bibliometric analysis aims to identify the most influential papers that inform current clinical practice and likely shape future research. The Thompson Reuters Web of Science citation database was interrogated using search terms to cover the breadth of erectile dysfunction. Results were ranked according to citation number with country of origin, journal, topic, year of publication, author and institution also analysed. The search criteria matched 12,570 manuscripts. The top 100 highest citation ranged from 3013 to 161 (median 229.5). The most cited manuscript reports the prevalence and risk factors of ED within the Massachusetts Male Aging Study. The most manuscripts were published by the Journal of Urology ( n = 15) with a total of 7913 citations. Institutions from the USA contributed the majority ( n = 55) with the UK ( n = 14) second. The most common theme represented was epidemiology ( n = 46) followed by treatment ( n = 27). This analysis provides a list of the most influential manuscripts within ED and illustrates what can be considered a ‘highly citable’ paper. The most influential papers in Erectile Dysfunction remain seminal works from the end of the last century. The most cited manuscript has been cited 194 times in the last 17 months showing its continued value. Only one paper published within the last decade has reached the top twenty exemplifying the relative lack of novel influential publications.

Erectile dysfunction is a common problem in primary care. Martin Steggall and colleagues discuss what needs to be assessed and the treatment options available Erectile dysfunction (ED) is defined as the inability of a man to get and maintain an erection that is sufficient for sexual intercourse, and is a common problem. ED commonly has a profound negative impact on quality of life in the patient and his partner, which can result in changes to sexual self-confidence. This article outlines strategies for identifying and managing ED in primary care, outlining what needs to be assessed and the various treatment options available to manage the condition.

Objectives: This study aimed to define contemporary perioperative management of patients undergoing penile implant surgery in the UK. Methods: All consultant urological surgeons responsible for the insertion of penile prostheses in the UK were invited to complete an online survey comprising of 25 questions relating to surgeon demographics, patient selection, preoperative work-up, intraoperative management and postoperative care. Anonymised responses underwent descriptive statistical analysis, with particular focus on measures employed to reduce the risk of perioperative infection. Results: Of the 34 invited surgeons, 26 (76.5%) responded to the survey. The majority reported undertaking between 10 and 30 cases in 2018 ( n=17; 65.4%). A total of 23 (88.5%) respondents reported employing a threshold for diabetic control, although the exact limit varied between surgeons. Most respondents ( n=22; 84.6%) reported routinely sampling urine for microscopy, culture and sensitivity. All but one ( n=25; 96.2%) reported routinely performing cavernosal washouts, with the most common solution being a mixture of gentamicin and vancomycin (42.3%). All reported routinely giving intravenous antibiotics on induction of anaesthesia, and although there was no clear consensus, most surgeons preferentially used an aminoglycoside in combination with one other agent (including penicillins or teicoplanin). Conclusion: The variation in current perioperative management demonstrates a potential need for the development and introduction of evidence-based guidelines to standardise practice nationwide. Level of evidence: 5

Introduction and objectives:The local recurrence rate of penile cancer following surgical excision is reported in many series to be between 6 and 29%. Intra-operative frozen section (FS) is a useful tool to ensure safe microscopic margins in organ-sparing procedures in penile cancer. In this series, we assessed the rates of positive margins and patterns of local recurrence in a multicentre cohort of patients undergoing penile-preserving surgery assisted by intra-operative FS analysis.Materials and methods:We reviewed all those patients for whom intra-operative FS was employed during penile-preserving surgery in three tertiary referral centres between 2003 and 2016. We assessed whether the use of FS altered the surgical technique and what affect it had on positive margins and recurrence rates.Results:A total of 169 patients were identified. Of these, intra-operative FS examination of the surgical margin was positive in 21 (12%) cases. Final histological examination confirmed cancer-free margins in all but one patient (99.4%). Overall, 9 patients developed local recurrence (5.3%).Conclusions:In this series, intra-operative FS contributed to a very low rate (5.3%) of local recurrence. We noted an extremely low positive margin rate (0.6%) which highlights the benefit of incorporating FS analysis into organ-preserving surgery for penile cancer.Level of evidence:Not applicable for this multicentre audit.

The sensing of gravity has emerged as an important tool in geophysics for applications such as engineering and climate research 1,2,3 where it provides the capability to probe otherwise inaccessible features under the surface of the Earth. Examples include the monitoring of temporal variations such as those found in aquifers4 and geodesy5. However, resolving metre scale underground features is rendered impractical by the long measurement times needed for the removal of vibrational noise6. Here, we overcome this limitation and open up the field of gravity cartography by realising a practical quantum gravity gradient sensor. Our design suppresses the effects of micro-seismic and laser noise, as well as thermal and magnetic field variations, and instrument tilt. The instrument achieves an uncertainty of 20 E (1 E = 10-9 s-2) and is used to perform a 0.5 m spatial resolution survey across a 8.5 m long line, detecting a 2 m tunnel with a signal to noise ratio of 8. The tunnel centre is localised using a Bayesian inference method, determining the centre to within ± 0.19 m in the horizontal direction and finding the centre depth as (1.89 -0.59/+2.3) m. The removal of vibrational noise enables improvements in instrument performance to directly translate into reduced measurement time in mapping. This opens new applications such as mapping the water distribution of aquifers and evaluating impacts on the water table7, detecting new features in archaeology8,9,10,11, determination of soil properties12 and water content13, and reducing the risk of unforeseen ground conditions in the construction of critical energy, transport and utilities infrastructure14, providing a new window into the underground.

Male genital emergencies relating to the penis and scrotum are rare and require prompt investigation and surgical intervention. Clinicians are often unfamiliar with the management of these conditions and may not work in a specialist centre with on-site expertise in genitourethral surgery. A series of consensus statements have been developed by an expert consensus committee comprising members of the BAUS Section of Andrology and Genitourethral Surgery together with experts from urology units throughout the UK. Priapism requires prompt assessment and treatment and these consensus statements provide guidance for UK practice.

Male genital emergencies relating to the penis and scrotum are rare and require prompt investigation and surgical intervention. Clinicians are often unfamiliar with the management of these conditions and may not work in a specialist centre with on-site expertise in genitourethral surgery. A series of consensus statements have been developed by an expert consensus comprising British Association of Urological Surgeons (BAUS) Section of Andrology and Genitourethral Surgery together with experts from units throughout the UK. Testicular trauma requires prompt investigation and treatment in order to prevent the development of subfertility or hypogonadism. This series of consensus statements provide guidance for UK practice.

Male genital emergencies relating to the penis and scrotum are rare and require prompt investigation and surgical intervention. Clinicians are often unfamiliar with the management of these conditions and may not work in a specialist centre with on-site expertise in genitourethral surgery. A series of consensus statements have been developed by an expert consensus committee comprising members of the British Association of Urological Surgeons (BAUS) Section of Andrology and Genitourethral Surgery together with experts from urology units throughout the UK. Penile amputation is a rare genital emergency, which requires prompt intervention and microsurgical reconstruction. The consensus statements will outline the management of these cases for non-specialist units, as well as recommendations for reconstruction for specialists.

Background Despite its importance, current practice in the emergency management of priapism in the United Kingdom is unknown. Aim To evaluate current practice in the emergency management of priapism in the United Kingdom. Methods All “full,” “associate urological specialist,” and “trainee” members of the British Association of Urological Surgeons (BAUS; leading membership-based organization for practitioners of urologic surgery in the United Kingdom) were invited to participate in an online survey. Questions related to the emergency management of priapism, access to tertiary andrology services, and use of guidelines. Outcomes Key outcome measures included frequency of encountered cases, access to specialist andrology support, confidence in key management steps, and use of current guidelines. Results 213 of 1,304 (16.3%) eligible members completed the survey. Most reported managing 1 case annually (median = 1, range = 0–>10). Only 7.0% transferred patients to a tertiary center and 87.8% believed they could access specialist andrology advice if required. Respondents were less confident in performing intracavernosal phenylephrine instillation (88.7%) compared with corporal aspiration (98.1%), with confidence lowest among trainee members. Only 68.5% reported performing the distal shunt procedure. Of the 212 respondents that chose to answer questions relating to guidelines, only 155 (73.1%) were aware of their existence, with those published by the European Association of Urology being most popular (53.8%). 205 (96.2%) respondents expressed an interest in the development of a UK-specific guideline, with 162 of 212 (76.4%) stating they would use this in practice. Clinical Implications Urologists in the United Kingdom support the development of UK-specific guidance on the emergency management of priapism for use within the context of the National Health Service. Strengths and Limitations This is the first study to assess current practice in the emergency management of priapism in the United Kingdom. Its strength is that most UK urologists were invited to participate through collaboration with the BAUS. Although the response rate of 16.3% is acceptable for a national survey of this nature, responses were self-reported, rendering them susceptible to bias. Conclusion This study demonstrates that some UK urologists lack confidence in key steps in the emergency management of priapism and identifies a strong level of support for the development of up-to-date UK-specific guidance.

Male genital emergencies relating to the penis and scrotum are rare and require prompt investigation and surgical intervention. Clinicians are often unfamiliar with the management of these conditions and may not work in a specialist centre with on-site expertise in genitourethral surgery. The aim of these consensus statements is to provide best practice guidance for urological surgeons based in the UK which are developed by an expert consensus. Penile fracture is a rare emergency and in most cases requires prompt exploration and repair to prevent erectile dysfunction and penile curvature.

Much has been made of the claim that humanity has ascended to the status of a terrestrial force and inaugurated a new geological epoch, the Anthropocene. While attention has been paid to the contestable nature of the epoch and its disputed histories, insufficient attention has been paid to the significance of the Anthropocene for political praxis. Contrary to much Anthropocenic discourse that articulates a renewed sense of mastery over nature through assertions of humanity’s complete subsumption of the environment, recent work in both science and technology studies and human geography suggests an alternate reading of the Anthropocene as an epoch without mastery, one where humanity exists in a permanent state of vulnerability. The political significance of this state of vulnerability is explored through a reading of popular TV show The Walking Dead, a post-collapse narrative of a world in ruins and overrun by zombies. On a ruined earth, political praxis is orientated not towards a return of the earth to it...

Doppler lidars are frequently operated in a mode referred to as arc scans, wherein the lidar beam scans across a sector with a fixed elevation angle and the resulting measurements are used to derive an estimate of the n minute horizontal mean wind velocity (speed and direction). Previous studies have shown that the uncertainty in the measured wind speed originates from turbulent wind fluctuations and depends on the scan geometry (the arc span and the arc orientation). This paper is designed to provide guidance on optimal scan geometries for two key applications in the wind energy industry: wind turbine power performance analysis and annual energy production. We present a quantitative analysis of the retrieved wind speed uncertainty derived using a theoretical model with the assumption of isotropic and frozen turbulence, and observations from three sites that are onshore with flat terrain, onshore with complex terrain and offshore, respectively. The results from both the theoretical model and observations show that the uncertainty is scaled with the turbulence intensity such that the relative standard error on the 10 min mean wind speed is about 30 % of the turbulence intensity. The uncertainty in both retrieved wind speeds and derived wind energy production estimates can be reduced by aligning lidar beams with the dominant wind direction, increasing the arc span and lowering the number of beams per arc scan. Large arc spans should be used at sites with high turbulence intensity and/or large wind direction variation when arc scans are used for wind resource assessment.

In the UK, the recent flourishing of organised resistance against austerity and the dominance of the free market over all aspects of life has done little to buck an overall trend of decreasing membership in political parties and similar organisations. Few informal organisational forms on the Left have fared better. However, these diminishing structures have certain key characteristics in common and there are suggestions of alternative political forms emerging in their stead. This article argues that such periods of decomposition, far from being an indication of failure, are an important and desirable element of social movement that can and should be deliberately factored in to political organising. Building from the notion that the basis of social change is the ability to move out of existing institutions, the article explores three methodologies of decomposition that bridge the divides between mythology, poetry, and political theory: Negative Capability, Eeriness, and the surrealist game.

Developments in assisted reproductive techniques (ART) have transformed the management of male factor infertility and the advent of intracytoplasmic sperm injection (ICSI) in 1993 was a landmark in the management of the infertile male. While this has been an undoubted success, it has led to a shift away from understanding and correcting the potential reversible causes of male factor infertility, to one that simply overcomes it with assisted reproductive techniques (ART). The aetiology of male infertility can broadly be divided into impaired spermatogenesis, or impaired sperm transport within the genital tract. The most challenging of these is male infertility due to azoospermia, which affects approximately 10-15% of infertile men (2.7million men in Europe). This article is protected by copyright. All rights reserved.

The asymmetric hydrogenation of α,β-unsaturated compounds using ene-reductase enzymes (primarily from the ‘Old Yellow Enzyme’ family of flavoproteins) is moving from an academic curiosity to a technology with potential industrial relevance. Continuing identification and reporting of ene-reductases with improved stability properties and higher turnover numbers will ensure their incorporation into industrial processes. This chapter highlights literature examples of bioreductions available to the modern practical chemist.

Recent advances in the field of quantum technology offer the exciting possibility of gravimeters and gravity gradiometers capable of performing rapid surveys with unprecedented precision and accuracy. Measurements with sub nano-g (a billionth of the acceleration due to gravity) precision should enable the resolution of underground structures on metre length scales. However, deducing the exact dimensions of the structure producing the measured gravity anomaly is known to be an ill-posed inversion problem. Furthermore, the measurement process will be affected by multiple sources of uncertainty that increase the range of plausible solutions that fit the measured data. Bayesian inference is the natural framework for accommodating these uncertainties and providing a fully probabilistic assessment of possible structures producing inhomogeneities in the gravitational field. Previous work introduced the probability of excavation map as a means to convert the high-dimensional space belonging to the posterior distribution to an easily interpretable map. We now report on the development of the inference model to account for spatial correlations in the gravitational field induced by variations in soil density.

The growing geographic disconnect between consumption of goods, the extraction and processing of resources, and the environmental impacts associated with production activities makes it crucial to factor global trade into sustainability assessments. Using an empirically validated environmentally extended global trade model, we examine the relationship between two key resources underpinning economies and human well--being-energy and freshwater. A comparison of three energy sectors (petroleum, gas, and electricity) reveals that freshwater consumption associated with gas and electricity production is largely confined within the territorial boundaries where demand originates. This finding contrasts with petroleum, which exhibits a varying ratio of territorial to international freshwater consumption, depending on the origin of demand. For example, although the United States and China have similar demand associated with the petroleum sector, international freshwater consumption is three times higher for the former than the latter. Based on mapping patterns of freshwater consumption associated with energy sectors at subnational scales, our analysis also reveals concordance between pressure on freshwater resources associated with energy production and freshwater scarcity in a number of river basins globally. These energy-driven pressures on freshwater resources in areas distant from the origin of energy demand complicate the design of policy to ensure security of fresh water and energy supply. Although much of the debate around energy is focused on greenhouse gas emissions, our findings highlight the need to consider the full range of consequences of energy production when designing policy.

Carbonyl reductase (CRED) technology has been shown to be an important tool for the rapid and efficient preparation of cis- and trans-4-tert-butylcyclohexanol, the precursors to the high volume fragrance ingredients known as Woody Acetate.

The present paper explores the trauma and challenges associated with career‐ending sports injury. The story presented here charts the moment of injury, the process of recovery and the challenges of starting a new life away from sport. Multi‐layered reflection is evidenced through an auto‐ethnographic storyline, one that illustrates the link between reflection (and reflection on reflections) and the process of ‘storytelling’. In stylistic terms the first and second authors appear (differentially) as embedded voices within the text. The first author, as auto‐ethnographer and storyteller, is positioned centrally in the main body of the paper. The second author acts as narrator in the introduction and summary sections. The auto‐ethnographic material is formulated from two sources. In a primary sense, the first author’s auto‐ethnographic writing dictates the structure and tone of the story. In addition, the author was encouraged to reflect further on his auto‐ethnographic tale (a process facilitated by the thi...

Anthracene-based, H + -driven, ‘off–on–off’ fluorescent PET (photoinduced electron transfer) switches are immobilized on organic and inorganic polymeric solids in the form of Tentagel ® and silica, respectively. The environment of the organic bead displaces apparent switching thresholds towards lower pH values whereas the Si–O − groups of silica electrostatically cause the opposite effect. These switches are ternary logic gate tags, one of which can be particularly useful in strengthening molecular computational identification (MCID) of small solid objects.

Seven years have elapsed since the Scottish Government launched its Hepatitis C Action Plan – a Plan to improve services to prevent transmission of infection, particularly among people who inject drugs (PWID), identify those infected and ensure those infected receive optimal treatment. The Plan was underpinned by industrial scale funding (around £100 million, in addition to the general NHS funding, will have been invested by 2015), and a web of accountable national and local multi-disciplinary multi-agency networks responsible for the planning, development and delivery of services. Initiatives ranged from the introduction of testing in specialist drug services through finger-prick blood sampling by non-clinical staff, to the setting of government targets to ensure rapid scale-up of antiviral therapy. The Plan was informed by comprehensive national monitoring systems, indicating the extent of the problem not just in terms of numbers infected, diagnosed and treated but also the more penetrative data on the number advancing to end-stage liver disease and death, and also through compelling modelling work demonstrating the potential beneficial impact of scaling-up therapy and the mounting cost of not acting. Achievements include around 50% increase in the proportion of the infected population diagnosed (38% to 55%); a sustained near two-and-a-half fold increase in the annual number of people initiated onto therapy (470 to 1050) with more pronounced increases among PWID (300 to 840) and prisoners (20 to 140); and reversing of an upward trend in the overall number of people living with chronic infection. The Action Plan has demonstrated that a Government-backed, coordinated and invested approach can transform services and rapidly improve the lives of thousands. Cited as “an impressive example of a national strategy” by the Global Commission on Drug Policy, the Scottish Plan has also provided fundamental insights of international relevance into the management of HCV among PWID.

The paper describes the implementation of a Bayesian model to assess novel gravimeters and gradiometers, which employ recent advances in cold matter wave interferometry to accurately measure micro-gravity. This has application to the resolution of underground structures, as an array of measurements at the surface can be used to infer what lies beneath. Potential applications of this technology include: improved identification of oil reservoirs; the detection of sink-holes to support civil engineering; detection of underground buildings; and geophysical mapping as a means to navigate in GPS denied environments. For the challenge of detecting underground voids at depths 10m beneath the Earth, the utility of the posterior distribution for computing probability of excavation maps is described and the impact of different sampling configurations and densities is investigated.

A 70-year-old heterosexual man attended the urology outpatient department complaining of penile discomfort for several months. On examination a 2 cm conical lesion projecting from the left side of his penile glans, consistent with a clinical diagnosis of a cutaneous horn of the penis, was noted (Figure 1). A wide local excision of the lesion was performed and pathological examination demonstrated hyperkeratosis of the stem consistent with a cutaneous horn. Further analysis of the base of the horn revealed a highly vascular tumour characterised by cells with an abnormal elongated shape, called spindle cells, in keeping with a rare case of Kaposi sarcoma (KS). A staging CT scan showed widespread inguinal, para-aortic, axillary and mediastinal lymphadenopathy (Figure 2). The most accessible node in the axilla was excised with histology demonstrating the so-called “onion skinning” of the mantle zone lymphocytes and hyalinisation of small vessels within the germinal centre with a lollipop sign pathognomonic of CD (Figure 3). Immunofluorescence was positive for Human Herpes Virus 8 (HHV-8). Hepatitis, Human Immunodeficiency Virus (HIV) and Tuberculosis serology were negative. Ganciclovir was commenced, but unfortunately further cutaneous lesions appeared on his limbs and trunk and he passed away from his disease 3 months later.

Working at the UK's defence laboratory gives Gareth Brown the ability to apply his physics and mathematics knowledge to real-world applications – and not necessarily in the ways you might expect. This article is Crown copyright © 2016 Dstl.

As information technology encroaches more and more into our lives, attention is turning to how the revolution started by silicon logic gates can be carried forward. Smaller-scale information processors is one approach to which chemical solutions can be imagined. The first molecular logic gates were built in Belfast a few years back. These artificial systems use chemical inputs and light output, reversing the natural roles existing within the eye. They can now do simple addition.

The relative size distributions of molecules of C60 and higher fullerenes observed in single walled carbon nanotubes (SWNTs) produced by arc vaporization of carbon in the presence of a mixed Ni/Y catalyst are described. The experimental and calculated imaging properties of the fullerenes, which were observed in ca. 5–10% of SWNTs, are also described. The in situ e-beam irradiation in a 300 kV field emission gun transmission electron microscope causes rapid coalescence of the fullerenes within the SWNTs. The incorporated fullerenes also directly impede crystal growth in SWNTs when their cavities are filled by the liquid phase capillary method.

In this paper theory for energy transport by combined conduction and radiation is briefly reviewed and a one-dimensional model for transient combined conduction and radiation heat transfer through a fibrous material is presented. The approach consists of using a Monte Carlo (MC) method to compute the so-called radiative flux distribution (RFD) and a radiative source-term distribution (RSD) function for a fibrous morphology. The functions are analogous to radiative configuration factors and the RSD is used to determine a source/sink term for the energy equation with Neumann boundary conditions. Using this model a solution for the evolving temperature distribution within the material is presented, this is contrasted with a representative conduction only model. Solutions are generated under the assumption of a grey fibrous material; the logical extension to non-grey anisotropic scattering fibrous material is then elucidated.

The majority of patients, who die from bladder cancer, ultimately do so from metastasis. A breakdown in the cell-cell bond seems likely to occur both, between cancer cells for tumour migration and between urothelial and endothelial cells for the development of metastases. Tight Junctions (TJ) exist between adjacent epithelial, endothelial and malignant cells and create a physiological barrier to the paracellular transport of solutes. They also contribute to cell polarity, regulate cell proliferation, and in addition are involved in cell signalling and cell-cell adhesion. Claudins are a group of trans-membrane proteins that contribute to TJ structure and function. Disruption of TJs with loss of TJ proteins, including claudins in cancer is thought to reduce cell-cell adhesion and contribute to invasion and metastasis. Altered expression of various claudins has been reported in several malignancies including bladder cancer, with an inverse correlation between the histological grade and the level of expression of some claudins. This review aims to explore the relationship between claudin expression and tumour progression in bladder cancer.

The encapsulation of ReOx within ReS2 inorganic fullerene-like cages is described for the first time. The encapsulate was prepared by the sulfidization of both hand-milled and ball-milled samples of ReO2; partial conversion of the oxide to the sulfide was achieved with the degree of sulfidization depending on the exposure to the sulfidizing agent, H2S.

Anthracene-based, H + -driven, ‘off–on–off’ fluorescent PET (photoinduced electron transfer) switches are immobilized on organic and inorganic polymeric solids in the form of Tentagel ® and silica, respectively. The environment of the organic bead displaces apparent switching thresholds towards lower pH values whereas the Si–O − groups of silica electrostatically cause the opposite effect. These switches are ternary logic gate tags, one of which can be particularly useful in strengthening molecular computational identification (MCID) of small solid objects.

The encapsulation of ReO(x) within ReS(2) inorganic fullerene-like cages is described for the first time. The encapsulate was prepared by the sulfidization of both hand-milled and ball-milled samples of ReO(2); partial conversion of the oxide to the sulfide was achieved with the degree of sulfidization depending on the exposure to the sulfidizing agent, H(2)S.

We demonstrate the first three-input molecular AND logic gate based on three chemical inputs as a direct way of detecting congregations of chemical species. The AND gate operates in water and responds to Na+, H+, and Zn2+ inputs with an enhanced fluorescence signal when pre-set concentration thresholds are exceeded. Future “lab-on-a-molecule” devices could have application in medicine for rapid disease screening.

Cluster formation can be induced in situ in SWNTs filled with ZrCl4 by electron beam irradiation of SWNT/ZrCl4 composites within a field emission gun transmission electron microscope (FEGTEM); the process represents a possible route to the synthesis of 1D-quantum dot arrays formed by related materials.