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Variations in the isotopologic composition of water vapour are fundamental for understanding the relative importance of different mechanisms of water vapour transport from the tropical upper troposphere to the lower stratosphere. Previous comparisons obtained from observations of H2O and HDO by satellite instruments showed discrepancies. In this work, newer versions of H2O and HDO retrievals from Envisat/MIPAS and SCISAT/ACE-FTS are compared. Specifically, MIPAS-IMK V5, MIPAS-ESA V8 and ACE-FTS V4.1/4.2 for the common period from February 2004 to April 2012 are compared for the first time through a profile-to-profile approach and comparison based on climatological structures. The comparison is essential for the scientific community to assess the quality of new satellite data products, a necessary procedure to validate further scientific work. Averaged stratospheric H2O profiles reveal general good agreement between 16 and 30 km. Biases derived from the profile-to-profile comparison are around zero between 16 and 30 km for MIPAS-IMK and ACE-FTS comparison. For HDO and δ D, low biases are found in the MIPAS-ESA and ACE-FTS comparison in the same range of altitudes, even if associated with a larger de-biased standard deviation. The zonally averaged cross sections of H2O and HDO exhibit the expected distribution that has been established in previous studies. For δ D the tropical depletion in MIPAS-ESA occurs at the top of the dynamical tropopause, but this minimum is found at higher altitudes in the ACE-FTS and MIPAS-IMK dataset. The tape recorder signal is present in H2O and HDO for the three databases with slight quantitative differences. The δ D annual variation for ACE-FTS data and MIPAS-ESA data is weaker compared to the MIPAS-IMK dataset, which shows a coherent tape recorder signal clearly detectable up to at least 30 km. The observed differences in the climatological δ D composites between databases could lead to different interpretations regarding the water vapour transport processes toward the stratosphere. Therefore, it is important to further improve the quality of level 2 products. [ABSTRACT FROM AUTHOR]

Physically unclonable functions (PUFs) have emerged as the most effective method against counterfeiting, leveraging the intrinsic randomness of objects to avoid data replication. However, despite their efficacy, the complexity and high cost of most PUF‐based counterfeiting labels hinder their practical application. Here, a high‐capacity PUF label based on vertically aligned perovskite nanowire (NW) arrays is demonstrated. The NW arrays are conveniently constructed using a low‐cost solution process using an anodized aluminum oxide template. Each pixel within the label is composed of closely packed CsPbBr3 NW arrays of different lengths, resulting in varied lasing signals. The collected signal of each pixel emerged from the lasing output of the NW arrays, generating high‐density and nonuniform multiple‐mode lasing to facilitate information encoding. A quaternary encoding mechanism is used to encode the number of laser modes per pixel. Impressively, it exhibits a mapping resolution of 1600 pixels within 400 µm2, achieving an impressive encoding capacity (1.97 × 10963) and a pixel density (4 bits µm−2) in this compact area. This work shows a promising approach for anticounterfeiting applications because of its simplicity, low cost, and high encoding capacity. [ABSTRACT FROM AUTHOR]

Balloon-borne cryogenic frost-point hygrometer (CFH) observations over two tropical stations Trivandrum (8.53° N, 76.87° E) and Hyderabad (17.47° N, 78.58° E) [2014–2017] along with Microwave Limb Sounder (MLS) observations [2011–2017] are used to examine the signatures of local and regional dynamics in the distribution of lower stratospheric water vapour over the Indian region. The column-integrated water vapour in the lower stratosphere (IWVLS) varies in the range 2.5–5 g/m2 with low values during winter and high values during summer monsoon and post monsoon seasons. About 50–75% of IWVLS lies in the lower regime of the lower stratosphere, the region from cold point tropopause (CPT) to 21 km (LS1). Hygropause is very near to the CPT in winter and pre-monsoon and 2–3 km above the CPT in summer-monsoon and post-monsoon. The CPT and the minimum in saturated mixing ratio (SMRmin) altitudes show a positive correlation, with SMRmin mostly occurring below the CPT. Though water vapour mixing ratio (WVMR) at CPT increases with increase in SMRmin, it is mostly less than the corresponding SMRmin value. CFH observations showed that the tape recorder signal in the LS1 is disturbed by the local/regional dynamics. While the amount of water vapour entering the lower stratosphere is higher over Hyderabad in winter and summer monsoon, it is higher over Trivandrum in the other two seasons. Hydration at the tropopause level is mainly determined by the overshooting/deep convection, monsoon dynamics and horizontal transport and dehydration is determined by temperature variations in the tropical tropopause layer (TTL). [ABSTRACT FROM AUTHOR]

Variations in the isotopological composition of water vapour are fundamental for understanding the relative importance of different mechanisms of water vapor transport from the tropical upper troposphere to the lower stratosphere. Previous comparisons obtained from observations of H2O and HDO by satellite instruments showed discrepancies. In this work, newer versions of H2O and HDO retrievals from Envisat/MIPAS are compared with data derived from SCISAT/ACE-FTS. Specifically, MIPAS-IMK V5, MIPAS-ESA V8, and ACE-FTS V4.1/4.2 for the common period from February 2004 to April 2012 are compared for the first time through a profile-to-profile approach and comparison based on climatological structures. Stratospheric H2O and HDO global average coincident profiles reveal good agreement. The smallest biases are found between 20 and 30 km, and the largest biases are exhibited around 40 km both in absolute and relative terms. For HDO, biases between -8.6-10.6 % are observed among the three databases in the altitudes of 16 to 30 km. However, around 40 km, ACE-FTS agrees better to MIPAS-IMK than MIPAS-ESA, with biases of -4.8% and -37.5%, respectively. The HDO bias between MIPAS-IMK and MIPAS ESA is 28.1 % at this altitude. The meridional cross-sections of H2O and HDO exhibit the expected distribution that has been established in previous studies. The tape recorder signal is present in H2O and HDO for the three databases with slight quantitative differences. The meridional cross-sections of (δD are in good agreement with the previous version of MIPAS-IMK and ACE-FTS data. In the temporal (δD variations, the results suggest that in the current data versions, the calculated isotopic composition ((δD) from MIPAS-IMK aligns more closely with expected stratospheric behavior for the entire stratosphere. Nevertheless, there are differences in the climatological (δD composites between databases that could lead to different interpretations regarding the water vapor transport processes toward the stratosphere, so it is important to intercompare these (δD observations. [ABSTRACT FROM AUTHOR]

Recently, much effort has been directed towards increasing the areal density of heat-assisted magnetic recording (HAMR). Here, we use our HAMR recording simulation that employs renormalized media parameters to examine the potential use of a pulsed laser instead of a continuous laser. Proper tuning of the synchronization between magnetic and laser pulses yields improved thermal gradients and comparable (or improved) recording performance relative to a continuous laser. Importantly, it also produces less average heat in the media, which is expected to improve near field transducer lifetime. Results also show that the optimized pulsed laser reduces adjacent track erasure relative to a continuous laser, which is important for non-shingled recording. [ABSTRACT FROM AUTHOR]

For over 40 years, starting in 1954, Popular Electronics Magazine was the major American publication for electrical hobbyists. The last years of the magazine saw it renamed Computers and Electronics. This is an unremarkable history but, as explained by Peter Bebergal about 3/4th of the way through his fascinating book Strange Frequencies, there is an issue from October 1995 that proposes experiments that deviate from the magazine’s usual gadgetry. The magazine is easily read at this website https://worldradiohistory.com/Archive-Poptronics/90s/95/PE-1995-10.pdf. The cover features a middle-aged man hunched over a reel-to-reel tape recorder. Behind him, he is haunted by a trio of faded ghost-like figures. The cover story is captioned, “Ghost voices: Are the dead trying to contact us through electronic means? Try these experiments and see for yourself” The article begins with a discussion of two electronic voice phenomena (EVP) experimenters of the 1950s: Frederich Jurgenson and Konstantin Raudive who claimed that with electronics they have communicated with the dead and that they have recordings of those voices preserved on tape. During his lifetime, Raudive asserted that he captured about 70,000 such communications. [ABSTRACT FROM AUTHOR]

After some 50 years, NASA will restart manned missions to the moon and beyond. The second scheduled mission of NASA's Artemis program (Artemis II) and the first scheduled crewed mission of NASA's Orion spacecraft will be launched in about November 2024. It is time to revisit the 1986 Space Shuttle Challenger accident involving magnetic tape data recorders and lessons learned from the investigation. The magnetic tape reels, which had been under 90 feet of seawater for 6 weeks off the Florida coast after the explosion, were recovered from three instrumentation (digital) tape recorders. Recorders' case seals were breached, and the tape was exposed to seawater and corrosion products. The tape layers were cemented, and tape reels could not be unwound and read. The author, working at IBM Development Lab in Tucson, was invited by the Reagan Commission to investigate the cause of the accident. One of the interests of the commission was to listen to recordings to determine what Challenger astronauts knew before the crash. Particularly, were they conscious after the blast and for how long and what were their last words? The author assembled an interdisciplinary team of 19 people. It took the team about a month to develop a tedious methodology to be able to unwind and make replicas of the damaged tapes which then could be read by NASA using conventional recorders. Some of the information was released to the press and was covered by major international newspapers and major evening news. It was reported that astronauts were alive for 73 s after takeoff up to the explosion and their last words were "Uh-Oh". It was dubbed as a "minor miracle" by the media and NASA. The paper provides a summary of investigations carried out by the IBM team and lessons learned. [ABSTRACT FROM AUTHOR]

This paper aims to study the work "Mutationen II für Cello und Tonband," written by Claudio Santoro, translating, and understanding the instructions in the cello part and in the tape. Regarding the recording of the media, the work deals with up-todate technological tools, such as studio recording and the use of audio programs, because tape recorders suggested by Claudio Santoro in the 1960s are no longer available. As the main results of the research, we can point out the recording of the piece and score editing in Portuguese, since the only edition previously available was a manuscript with most of the instructions in German. This research supports cellists interested in the study and performance of the piece, helping this way to spread knowledge about the work, which is one of the first pieces for cello and electroacoustics in the international repertoire. [ABSTRACT FROM AUTHOR]

Most of the literary criticism has pointed out the importance of inscribing the voices of others or giving voice to others in Rodolfo Walsh's writing. However, the material and technological conditions under which those voices appear in his texts have been scarcely addressed. In this essay I delve into sound studies to explore the uses of the tape recorder in the writing of ¿Quién mató a Rosendo? (1969). I propose the notion of a phonoautographic writing to refer to a textual practice conceived as a transcription of voices. The article analyzes the phonoautographic writing in ¿Quién mató a Rosendo? and explores how the tape recorder allowed Walsh to incorporate and manipulate the voices of his working-class characters. My argument is that Walsh used the tape recorder to register the workers' voices in order to rearticulate in a personal way the sonic legacy of Peronism in the late 60s, a moment of crisis in the representation of the Argentine labor movement. [ABSTRACT FROM AUTHOR]

Scattering scanning near-field optical microscopy enables optical imaging and characterization of plasmonic devices with nanometer-scale resolution well below the diffraction limit. This technique enables developers to probe and understand the waveguide-coupled plasmonic antenna in as-fabricated heat-assisted magnetic recording heads. In order to validate and predict results and to extract information from experimental measurements that is physically comparable to simulations, a model was developed to translate the simulated electric field into expected near-field measurements using physical parameters specific to scattering scanning near-field optical microscopy physics. The methods used in this paper prove that scattering scanning near-field optical microscopy can be used to determine critical sub-diffraction-limited dimensions of optical field confinement, which is a crucial metrology requirement for the future of nano-optics, semiconductor photonic devices, and biological sensing where the near-field character of light is fundamental to device operation. [ABSTRACT FROM AUTHOR]

The AirCore is a long coiled tube that acts as a "tape recorder" of the composition of air as it is slowly filled or flushed. When launched by balloon with one end of the tube open and the other closed, the initial fill air flows out during ascent as the outside air pressure drops. During descent atmospheric air flows back in. I describe how we can associate the position of an air parcel in the tube with the altitude it came from by modeling the dynamics of the fill process. The conditions that need to be satisfied for the model to be accurate are derived. The extent of the mixing of air parcels that enter at different times is calculated so that we know how many independent samples are in the tube upon landing and later when the AirCore is analyzed. [ABSTRACT FROM AUTHOR]

This classroom action research aims to improve students' listening skills through the application of animated films. The subjects in this study were second semester students at STAIN Gajah Putih Takengon. The data in this study were obtained from observation sheets, tests and questionnaires. Based on the analysis that has been carried out, it is known that in cycle I, 68.57% of students are actively involved in learning and 70% of students are motivated and enthusiastic about learning. Whereas in cycle II, 77.14% of students were actively involved and 88.57% of students were motivated and enthusiastic about participating in learning. In the preliminary study, the average listening ability of students was 53.43%, in the first cycle the students' average listening ability increased to 59.37%, and in the second cycle the increase reached 76.71%. The results of the student response questionnaire showed that 87.5% felt happy with the application of animated films and 81.25% felt that the use of animated films had an effect on listening skills. 93.75% said it was easier to practice listening skills with animated films and 90.63% preferred learning to listen with animated films compared to other media such as tape recorders, and 93.75% disagreed with learning to listen without using audio visual aids. [ABSTRACT FROM AUTHOR]

This article attends to the aural dimensions of Ann Quin's Three (1966). It argues that just as high modernist texts developed symbiotically with the emergent sound technologies of the late-nineteenth and early-twentieth centuries, so might Quin's novel be read for its engagement with the tape recorder which rose to commercial prominence after 1945. Aiming to contextualize Quin's writing on tape, the article considers the history and prehistory of the medium, as well as its appropriation by Quin's contemporaries in music, film, and the visual arts. Through the figure of tape, Three finds ways of valuing ambience and materiality, while resisting transactional and suspicious forms of knowledge. [ABSTRACT FROM AUTHOR]

Purpose - This paper deals with the question of finding traces of historical film sound production process in production magnetic tapes. with regards to its material manifestations. Film sound production leaves traces of its development and underlying creative processes in all of its stages. Materials that contain these traces can be used to retrospectively analyse both the development of the film work in question and the creative processes that lie behind its sound and music. Design/Methodology/Approach - As part of the research, magnetic materials, present at the Národní filmový archiv in Prague, that contain the preliminary and final versions of the film sound were analysed. Data contained on their packaging was used in a case study that describes individual types of audio carriers and their contents. Digitized tapes were used for a quantitative and qualitative analysis of the content of the materials. These case studies were further used to describe the relationship between individual generations of the film and non-film material. Quantitative and qualitative analysis is followed by an effort to modify the Functional Requirements for Bibliographic Records (FRBR) standard in order to create a conceptual model that reflects both the material heterogeneity of film production magnetic tapes and the manifestations of sound of a specific film work in all its available materials (the script, magnetic audio tapes and the film negative and prints). Results - This study presents the main historical, theoretical and practical approaches to film sound research. The text contains an overview of the types of sound recordings found on magnetic carriers connected to film sound production, their classification and distribution of the main sound elements (music, foley, dialogues). Furthermore, the study presents an analytical comparison of the expressions of creative concepts found in the soundtrack of the Czech 1970s film The Little Mermaid across all the available materials, as well as a conceptual model which connects all of the film sound archival sources. Originality/Value - Material manifestations of film sound are key to understanding the period process of film sound production. On the example of the work of Zdeněk Liška, the foremost Czech film music composer, a possible approach to understanding the historical process of sound production was modelled. The conceptual model further serves as a basis of a cataloguing module, which will be used by the Národní filmový archiv (the National Film Archive in Prague) for its emergent film catalogue. This topic is yet to be covered by the Czech scientific literature. [ABSTRACT FROM AUTHOR]

The present research examined procrastination behavior and selfefficacy among postgraduate students by using mixed method research in two studies. Objective of this research was to measure procrastination, self-efficacy and further to explore the factors behind these behaviours through quantitative and qualitative research, respectively. For study-I, in quantitative research, sample of 282 students was selected by using stratified random sampling technique. To measure procrastination “Procrastination Scale” for student population (Lay, 1986) and for Self-efficacy “General Selfefficacy Scale” (Schwarzer & Jerusalem, 1995) were used. Descriptive statistics, correlation analysis and Chi-square were used to analyse the data. Results indicated that there is a significant negative correlation between procrastination behavior and selfefficacy. The level of procrastination was found at non-clinical level 5(1.5%), sub-clinical level 165(68.5%), clinical level 110(39.0) and 2(0.7%) reported the need to seek clinical attention. Findings of chisquare illustrate no association of procrastination with demographic of age, faculty and GPA. In study-II, through qualitative approach, a focus group discussion was conducted with eight participants. Data were recorded by a tape recorder which was transcribed and analysed by using thematic analysis. Results revealed four themes from qualitative discussion; 1) description of procrastination behavior, 2) casual and precipitating factors, 3) impact on life and 4) strategies to overcome/reduce procrastination behavior. Through the findings of both studies, it can be concluded that procrastination behaviour is prevalent among students and there is a need to implement strategies to reduce this behaviour. [ABSTRACT FROM AUTHOR]

Interest towards communities characterized by oral tradition has taken the form of ethnological and/or anthropological field research on this topic over the past two centuries. With the invention of the tape recorder, the difficulty of recording field information was reduced as it enabled real-time recording of testimonies provided by informants; the process became even more accessible once digital information storage became available. In parallel with the efforts of the researcher--outsider--to document realities considered relevant for the culture of traditional societies, some of the insiders became aware of the need to write down such information, which they recognized to be defining for their own social group. This article thus focuses on a particular practice in writing down ethnographic information, namely the existence of notebooks in which oral texts of different types and with different functions are recorded. To build the argument, I draw on the example of such notebooks held by the Folklore Archive of the West University of Timișoara, namely five manuscripts signed by Gheorghe Andraș, a teacher from Sânnicolau Mare, a small town in western Romania. Written in the first half of the twentieth century, these notebooks are statements of the inner calling their author felt to write down this type of ethnographic information, under the influence of national policies supporting ethnographic field research. [ABSTRACT FROM AUTHOR]

The AirCore is a long coiled tube that acts as a "tape recorder" of the composition of air as it is slowly filled or flushed. When launched by balloon with one end of the tube open and the other closed, the initial fill air flows out during ascent as the outside air pressure drops. During descent atmospheric air flows back in. We describe how we can associate the position of an air parcel in the tube with the altitude it came from by modeling the dynamics of the fill process. The conditions that need to be satisfied for the model to be accurate are derived. The extent of mixing of air parcels that enter at different times is calculated, so that we know how many independent samples are in the tube upon landing, and later when the AirCore is analyzed. [ABSTRACT FROM AUTHOR]

This study aims to determine the experience of nurses in health centers regarding the factors that affect the prevention and control of TB infection and to determine the risk of nosocomial infection transmission. This research is qualitative research using a phenomenological approach, structured interviews. The research sample was 4 Health Centers nurses in Indonesia. The sampling technique was total sampling. The interview in the confidential meeting room, conducted in Indonesian, lasted about 30 minutes. Participants' responses were recorded during the interview. We typed and examined the coded script. Interviews were recorded using a tape recorder. Four themes were found, namely the lack of health service facilities, socio-cultural factors, patient behavior in utilizing health services. [ABSTRACT FROM AUTHOR]

In the late 1950s and early 1960s, Pauline Oliveros developed new techniques for improvising with new electronic instruments, which she described using language and metaphors from cybernetics and information theory. First using just a tape recorder, and later using a series of tape recorders connected to an unstable pair of oscillators, Oliveros created what she later called a 'very unstable nonlinear musicmaking system' (Oliveros, Pauline. 2016a. "Improvising Composition: How to Listen to the Time Between." In Negotiated Moments: Improvisation, Sound, and Subjectivity, edited by Gillian H. Siddall, and Ellen Waterman, 75–90. Durham, NC: Duke University Press). By positioning herself as only one member of an instrumental system that facilitated the self-regulating flow of sound as signal—operating as air pressure waves, electrical waves, psychoacoustic phenomena, and even human consciousness—Oliveros began to reconceptualize the role of her body in musical performance. By the early 1970s, Oliveros began to embrace the new kinds of musical performance and musical subjectivities produced by this system as a part of her exploration of gender in music, positing the concept of 'androgynous music'—defined as music that is simultaneously 'linear' and 'nonlinear'. Oliveros thought of her performance practice as one that could destabilise socially constructed musical identities of composition, performance, and listening, and also integrate different modalities of interacting with musical 'signal'. This article maps Oliveros's cybernetic, improvisatory practices with her earliest electronic systems, showing how her performance within these systems laid the groundwork for her later theorisations of technology, gender, and the body. [ABSTRACT FROM AUTHOR]

Technical media such as playback devices play a key role in popular music culture. Hence, it is hardly surprising that extensive cultural-historical research with a focus on such devices has already been conducted. But almost all researchers working on the cultural history of playback devices in Germany concentrate on West Germany, while the media history of the GDR is treated marginally. In this article, I aim to contribute to the historiography of the GDR's popular music with a focus on material culture. In doing so, I analyse archival material of the state-owned company VEB Messgerätewerk Zwönitz, which manufactured tape recorders in the 1950s and 1960s. The focus is on documents regarding the tape recorder BG 20. The sources, for example technical reports, advertisements, and letters from the government, demonstrate that the manufacturing of music devices in the GDR was highly influenced by the political conditions. [ABSTRACT FROM AUTHOR]

There is a striking variance between the sounds of highlife music recorded in the 1950s and 1960s and that of the 1970s. This difference can be attributed partly to the advancement of recording technology, a shift from shellac to vinyl records as well as the advent of multi-track tape recorders in Ghana. The 1970s had a unique highlife sound that can be situated within and explained by the socio-cultural context of recording approaches embraced by studio engineers. This paper investigates the technological approaches to the production of highlife songs at the Ghana Film Studio (GFS) and how they reshaped the highlife soundscape in the 1970s. It also draws attention to the influence of Francis Kwakye, the then resident recording engineer of GFS as a case study to explore highlife sound on records within this period. Employing document review, audio review, observations and interview for data collection, the paper reveals that the engineering techniques and tools employed on the recordings were socio-culturally influenced and constructed to resonate with the Ghanaian identity of the time. It further argues that the recording activities have been guided largely by a new imagination of the highlife sound recordings framed within a certain Ghanaian nationalistic context. The paper concludes that the methods employed to record highlife music of the 1970s were masterminded essentially from a Ghanaian socio-cultural sound perspective. [ABSTRACT FROM AUTHOR]

For heat assisted magnetic recording (HAMR) media development, measurement of erasure temperature (Te) is interesting and important for practical HAMR testing and applications. Here, we present an investigation on Te measurements of L10 ordered FePt granular HAMR media made using a Laser Heating (LH) method on a home-built HAMR write test system versus that from a bulk heating approach. The HAMR write test system provides HAMR writing, micro-MOKE (magneto- optical Kerr effect) signal detection, and MOKE imaging functions at the same testing spot in one single system. Magnetic force microscopy (MFM) and magnetic Kerr microscopy observations of the scanning laser induced degradation/erasure/demagnetization of the pre-recorded magnetic patterns on disk media (over a wide area of a few hundreds of μm2) show that the magnetic (MFM and Kerr signal) amplitude of the pre-recorded magnetic patterns decreases slowly with increasing laser power (Pw) (/temperature rise) for Pw≲66 mW and then drops sharply to nearly zero for Pw⩾~72 mW (the laser power corresponding to complete thermal erasure when the media temperature is ~Te). It was further found that this trend of magnetic amplitude reduction with increased Pw is similar to that from magnetic amplitude decrease of pre-recorded magnetic patterns with increased bulk heating temperature. The temperature for complete erasure at laser power, Pw=72 mW for the LH method, corresponds therefore to ~650K (≈Te) for the bulk heating methods. Besides fast measurement, LH (as a comparable and viable approach for erasure measurement) is dynamic, localized, and has time scales closer to practical HAMR situation. [ABSTRACT FROM AUTHOR]

FEM-boundary integral method micromagnetic software was used to analyze the recording field response of an indented magnetic head to high frequency recording currents (1-4 GHz). Next, micromagnetic simulations of heat-assisted magnetic recording were performed and the signal-tonoise ratio (SNR) calculated at high frequencies. With a soft magnetic underlayer, the head field was large enough and gave higher SNRs. The large head field strength at low frequency did not cause any deterioration of the SNR. [ABSTRACT FROM AUTHOR]

We present a study on atomic ordering within individual grains in granular L10-FePt thin films using transmission electron microscopy techniques. The film, used as a medium for heat assisted magnetic recording, consists of a single layer of FePt grains separated by non-magnetic grain boundaries and is grown on an MgO underlayer. Using convergent-beam techniques, diffraction patterns of individual grains are obtained for a large number of crystallites. The study found that although the majority of grains are ordered in the perpendicular direction, more than 15% of them are multi-variant, or of in-plane c-axis orientation, or disordered fcc. It was also found that these multi-variant and in-plane grains have always grown across MgO grain boundaries separating two or more MgO grains of the underlayer. The in-plane ordered portion within a multi-variant L10-FePt grain always lacks atomic coherence with the MgO directly underneath it, whereas, the perpendicularly ordered portion is always coherent with the underlying MgO grain. Since the existence of multi-variant and in-plane ordered grains are severely detrimental to high density data storage capability, the understanding of their formation mechanism obtained here should make a significant impact on the future development of hard disk drive technology. [ABSTRACT FROM AUTHOR]

James Carey famously repositioned the spotlight on the techniques of journalism itself as a practice devoted to the task of defining "what is to be considered real: what can be written about and how it can be understood." This article looks at shorthand, the tape recorder, and the cameraphone as material objects that shape journalism as a practice even as they, in turn, are discursively constructed by and situated in journalists' quest to establish their authority to define, in Carey's words, what is real. A historical study of recording technologies ultimately demonstrates both a continuing desire to escape the "imperfect medium" of the human body in favour of one that is able to better select, process, and store information (Kittler, F. 1999. Gramophone, Film, Typewriter. Edited by G. Winthrop-Young. Stanford University Press), and the ultimate futility of that desire. If they fail, it is at least partly because those tools are already embedded with certain values of who is human, who is trustworthy, and who is or can be objective. [ABSTRACT FROM AUTHOR]

Three-dimensional reconstruction algorithms have been developed, which determine the hot-spot velocity, hot-spot apparent ion temperature distribution, and fuel areal-density distribution present in laser-direct-drive inertial confinement fusion implosions on the OMEGA laser. These reconstructions rely on multiple independent measurements of the neutron energy spectrum emitted from the fusing plasma. Measurements of the neutron energy spectrum on OMEGA are made using a suite of quasi-orthogonal neutron time-of-flight detectors and a magnetic recoil spectrometer. These spectrometers are positioned strategically around the OMEGA target chamber to provide unique 3D measurements of the conditions of the fusing hot spot and compressed fuel near peak compression. The uncertainties involved in these 3D reconstructions are discussed and are used to identify a new nTOF diagnostic line of sight, which when built will reduce the uncertainty in the hot-spot apparent ion temperature distribution from 700 to <400 eV. [ABSTRACT FROM AUTHOR]

Writing closely spaced tracks in the cross-track direction helps increase the storage density but leads to erasure of the adjacent tracks. This phenomenon is called adjacent track erasure (ATE). This article aims to establish the presence and numerical extent of ATE in different heat-assisted magnetic recording (HAMR) media. We find that thermal exchange coupled composite (ECC) media can be more susceptible to ATE compared with single layer FePt media of equivalent thickness. We implement optimization techniques to reduce the ATE in different media and increase the recording signal to noise ratio (SNR) in this process. While the ATE in single layer FePt media seems to be relatively impervious to changes in the applied field angle, small field angles appear to reduce the ATE for the high $T_{c}$ thermal ECC media. However, small angle also reduces the SNR, leading to the conclusion that 30° actually yields the best SNR even in the presence of overwrite. Introducing a finite intergranular exchange coupling improves the writing performance of the single layer FePt and reduces the ATE. We rigorously calculate the thermal decay constant and use it to evaluate the performance of pulsed laser recording. Finally, we establish a hypothesis that helps explain the presence of ATE in different HAMR media. We believe the ATE is proportional to the thermal stability factor at a temperature just below the write temperature. The proposed hypothesis correctly predicts the ATE in the single layer FePt media assuming coherent rotation. Our results can help increase the HAMR storage density and make HAMR media resistant to the ATE. [ABSTRACT FROM AUTHOR]

We present a proof of principle for onsite calibration of a radiochromic film (EBT3) using CR-39 as an absolute proton-counting detector and laser-accelerated protons as a calibration source. A special detector assembly composed of aluminum range filters, an EBT3 film, and a CR-39 detector is used to expose the EBT3 film with protons in an energy range of 3.65 MeV–5.85 MeV. In our design, the proton beam is divided into small beamlets and their projection images are taken on the EBT3 film and the CR-39 detector by maintaining a certain distance between the two detectors. Owing to the geometrical factor of the configuration and scattering inside the EBT3, the areal number density of protons was kept below the saturation level of the CR-39 detector. We also present a method to relate the number of protons detected on the CR-39 in a narrow energy range to protons with a broad energy spectrum that contribute to the dose deposited in the EBT3 film. The energy spectrum of protons emitted along the target normal direction is simultaneously measured using another CR-39 detector installed in a Thomson parabola spectrometer. The calibration curves for the EBT3 film were obtained in the optical density range of 0.01–0.25 for low dose values of 0.1 Gy–3.0 Gy. Our results are in good agreement with the calibrations of the EBT3 film that are traditionally carried out using conventional accelerators. The method presented here can be further extended for onsite calibration of radiochromic films of other types and for a higher range of dose values. [ABSTRACT FROM AUTHOR]

Fiber optic sensing technology has recently become popular for oil and gas, mining, geotechnical engineering, and hydrogeology applications. With a successful track record in many applications, distributed acoustic sensing using straight fiber optic cables has become a method of choice for seismic studies. However, distributed acoustic sensing using straight fiber optic cables is not able to detect off-axial strain, hence a helically wound cable design was introduced to overcome this limitation. The helically wound cable field data in New Afton deposit showed that the quality of the data is tightly dependent on the incident angle (the angle between the ray and normal vector of the surface) and surrounding media. We introduce a new analytical two-dimensional approach to determine the dynamic strain of a helically wound cable in terms of incident angle in response to elastic plane waves propagating through multilayered media. The method can be used to quickly and efficiently assess the effects of various materials surrounding a helically wound cable. Results from the proposed analytical model are compared with results from numerical modeling obtained with COMSOL Multiphysics, for scenarios corresponding to a real installation of helically wound cable deployed underground at the New Afton mine in British Columbia, Canada. Results from the analytical model are consistent with numerical modeling results. Our modeling results demonstrate the effects of cement quality, and casing installment on the quality of the helically-wound cable response. Numerical modeling results and field data suggest that, even if reasonably effective coupling achieved, the soft nature of the rocks in these intervals would result in low fiber strains for the HWC. The proposed numerical modeling workflow would be applied for more complicated scenarios (e.g., non-linear material constitutive behaviour, and the effects of pore fluids). The results of this paper can be used as a guideline for analyzing the effect of surrounding media and incident angle on the response of helically wound cable, optimizing the installation of helically wound cable in various conditions, and to validate boundary conditions of 3-D numerical model built for analyzing complex scenarios. [ABSTRACT FROM AUTHOR]

In heat-assisted magnetic recording, minimization of optical laser power is important for the reliability of the head-disk interface. In this paper, a prototype heat-assisted magnetic recording system is used to investigate the relationship between the needed optical laser power and disk drive design parameters. In particular, the change of optical laser power, which is a function of the laser current, is investigated for different disk radii and write head flying heights while keeping the write width of the recorded signal constant. In addition, the dependence of laser power during writing is studied as a function of the thickness and material properties of a very thin "capping layer" on the top of the recording magnetic layer. The results show that laser power and media design parameters play a crucial role in heat-assisted magnetic recording devices. [ABSTRACT FROM AUTHOR]

We fabricate perpendicular magnetic recording media comprising two antiferromagnetically coupled Co/Pt multilayers and investigate its magnetic properties by ferromagnetic resonance (FMR) measurement. In such media, the magnetizations of the two perpendicular magnets are designed to compensate each other in the remanent state in order to reduce the dipolar field, which is a limiting factor in high-density magnetic recording devices. We measure FMR absorption spectra of the media and estimate the magnetic anisotropy and interlayer exchange coupling. We also demonstrate that FMR measurement can be employed to read out the magnetization direction. The principles behind this readout method are different from those behind the conventional method of detecting the stray field from the media by means of a magnetoresistive sensor; therefore, the proposed readout method is applicable to magnetic recording media having zero remanent magnetization. We expand this readout scheme to three-dimensional magnetic recording with several vertically stacked recording layers. By providing each recording layer with a different FMR frequency, we experimentally confirm that layer selective readout is possible. [ABSTRACT FROM AUTHOR]

Chemically ordered and highly textured L10 FePt-C granular films are potential media for future heat-assisted magnetic recording. Vibrating sample magnetometry of such films in fields up to 14 T reveals a perpendicular coercivity of up to μ0HC=4.92 T and an anisotropy field of μ0HA=9.2 T, which translates to a (uni-axial) anisotropy constant as high as KU=5.3 MJ/m3. An analysis of the remanent magnetization and demagnetization curves shows that the spatially separated FePt nanoparticles act as a Stoner-Wohlfarth ensemble of uni-axial nanomagnets with negligible dipolar inter-particle coupling. The magnetic texture spread of 23° as determined from an analysis of the hard axis magnetization curve is found to be clearly larger than the structural texture width of roughly 3°. Aberration corrected high-resolution transmission electron microscopy reveals that the latter is due to the remaining roughness of the seed layer that causes the particle growth to nucleate at step edges of this layer. [ABSTRACT FROM AUTHOR]

Superparamagnetic colloidal particles can be reversibly assembled into wheel-like structures called microwheels (μwheels), which roll on surfaces due to friction and can be driven at user-controlled speeds and directions using rotating magnetic fields. Here, we describe the hardware and software to create and control the magnetic fields that assemble and direct μwheel motion and the optics to visualize them. Motivated by portability, adaptability, and low-cost, an extruded aluminum heat-dissipating frame incorporating open optics and audio speaker coils outfitted with high magnetic permeability cores was constructed. Open-source software was developed to define the magnitude, frequency, and orientation of the magnetic field, allowing for real-time joystick control of μwheels through two-dimensional (2D) and three-dimensional (3D) fluidic environments. With this combination of hardware and software, μwheels translate at speeds up to 50 µm/s through sample sizes up to 5 × 5 × 5 cm3 using 0.75 mT–2.5 mT magnetic fields with rotation frequencies of 5 Hz–40 Hz. Heat dissipation by aluminum coil clamps maintained sample temperatures within 3 °C of ambient temperature, a range conducive for biological applications. With this design, μwheels can be manipulated and imaged in 2D and 3D networks at length scales of micrometers to centimeters. [ABSTRACT FROM AUTHOR]

A proof-of-principle CR-39 based neutron-recoil-spectrometer was built and fielded on the Z facility. Data from this experiment match indium activation yields within a factor of 2 using simplified instrument response function models. The data also demonstrate the need for neutron shielding in order to infer liner areal densities. A new shielded design has been developed. The spectrometer is expected to achieve signal-to-background greater than 2 for the down-scattered neutron signal and greater than 30 for the primary signal. [ABSTRACT FROM AUTHOR]

We have explored a new electrically conductive underlayer material to grow (001) textured L10-FePt films on glass substrates for potential application in ultrahigh density magnetic recording media. We found (Mg0.2Ti0.8)O (MTO) polycrystalline film grows with a strong (001) texture on Cr buffer layer, which induces strong (001) texture of L10-FePt polycrystalline and granular films. Strong perpendicular anisotropy of 3.8 × 107 erg/cm3 and coercivity of 15 kOe of a FePt-C film has been demonstrated using the MTO underlayer on glass substrates. [ABSTRACT FROM AUTHOR]

The possibility of selective magnetization switching in a three-layered stacked magnetic pillar was discussed using micromagnetic simulation that considers three-dimensional magnetic recording. Selective magnetization switching is possible with the assistance of a circularly polarized microwave field with an adequate corresponding frequency. This study demonstrates that the value of the saturation magnetization of the magnetic layers is critical in suppressing selective magnetization switching errors caused by magnetostatic fields. A relatively large saturation magnetization of up to 600 emu/cm3 in the second layer also allows successful selective magnetization switching, thus enabling three-dimensional magnetic recording. However, damping constants smaller than 0.1 for the magnetic layers are crucial in the model calculations because of the limited strength of the microwave fields applied to the stacked magnetic pillar. The leakage flux is also estimated considering a multi-bit reproducing process, where eight-digit signals are obtained depending on the magnetization states of the stacked magnetic pillar. [ABSTRACT FROM AUTHOR]

Ultrathin amorphous carbon (a-C) films are extensively used as protective overcoats of magnetic recording media. Increasing demands for even higher storage densities have necessitated the development of new storage technologies, such as heat-assisted magnetic recording (HAMR), which uses laser-assisted heating to record data on high-stability media that can store single bits in extremely small areas (∼1 Tbit/in.2). Because HAMR relies on locally changing the coercivity of the magnetic medium by raising the temperature above the Curie temperature for data to be stored by the magnetic write field, it raises a concern about the structural stability of the ultrathin a-C film. In this study, rapid thermal annealing (RTA) experiments were performed to examine the thermal stability of ultrathin hydrogenated amorphous carbon (a-C:H) films deposited by plasma-enhanced chemical vapor deposition. Structural changes in the a-C:H films caused by RTA were investigated by x-ray photoelectron spectroscopy, Raman spectroscopy, x-ray reflectivity, and conductive atomic force microscopy. The results show that the films exhibit thermal stability up to a maximum temperature in the range of 400-450 °C. Heating above this critical temperature leads to hydrogen depletion and sp2 clustering. The critical temperature determined by the results of this study represents an upper bound of the temperature rise due to laser heating in HAMR hard-disk drives and the Curie temperature of magnetic materials used in HAMR hard disks. [ABSTRACT FROM AUTHOR]

In this work, we investigate the possibility of approximating saturable nonlinearity, which is commonly used in complex Ginzburg–Landau equation (CGLE) for modelling resonant interaction of an electromagnetic field with nonlinear media, with cubic-quintic (CQ) nonlinearity. To validate the suggested approximations, we use variational method to estimate 2D analytical solutions of the CGLE with both saturable and CQ nonlinearity. The paper compares three ways to determine parameters of the CQ approximation and discusses the obtained results in terms of accuracy. [ABSTRACT FROM AUTHOR]

Using particle-in-cell simulations, we demonstrate an improvement of the target-normal-sheath acceleration (TNSA) of protons in non-periodically nanostructured targets with micron-scale thickness. Compared to standard flat foils, an increase in the proton cutoff energy by up to a factor of two is observed in foils coated with nanocones or perforated with nanoholes. The latter nano-perforated foils yield the highest enhancement, which we show to be robust over a broad range of foil thicknesses and hole diameters. The improvement of TNSA performance results from more efficient hot-electron generation, caused by a more complex laser–electron interaction geometry and increased effective interaction area and duration. We show that TNSA is optimized for a nanohole distribution of relatively low areal density and that is not required to be periodic, thus relaxing the manufacturing constraints. [ABSTRACT FROM AUTHOR]

In this study, we experimentally investigate the lubricant depletion as well as the temperature distribution caused by pulsed laser irradiation heating and discuss the fundamental characteristics. It was determined that the maximum temperature increased as the duty ratio increased. However, the rate of the maximum temperature change due to the duty ratio was comparatively small. Therefore, it was suggested that the maximum temperature was almost constant when the duty ratio was more than 50% under experimental conditions. The thermal distribution or the thermal gradient also depended on the duty ratio and increased as this ratio decreased. It was also determined that the depletion of the lubricant film due to pulsed laser heating was smaller than that due to continuous laser heating. Moreover, it depended on the duty ratio and increased as the duty ratio increased. In addition, it depended on the full width at half maximum (FWHM) of the temperature distribution due to pulsed laser irradiation heating and increased as the FWHM is increased. Therefore, it is also suggested that the lubricant depletion issue will not be as critical in actual heat-assisted magnetic recording system because the FWHM would be very small under practical circumstances. [ABSTRACT FROM AUTHOR]

Modulation of a microwave signal generated by the spin-torque oscillator (STO) based on a magnetic tunnel junction (MTJ) with perpendicularly magnetized free layer is investigated. Magnetic field inductive loop was created during MTJ fabrication process, which enables microwave field application during STO operation. The frequency modulation by the microwave magnetic field of up to 3 GHz is explored, showing a potential for application in high-data-rate communication technologies. Moreover, an inductive loop is used for self-synchronization of the STO signal, which after field-locking, exhibits significant improvement of the linewidth and oscillation power. [ABSTRACT FROM AUTHOR]

The annual variation of δD in the tropical lower stratosphere is a critical indicator for the relative importance of different processes contributing to the transport of water vapour through the cold tropical tropopause region into the stratosphere. Distinct observational discrepancies of the δD annual variation were visible in the works of Steinwagner et al. (2010) and Randel et al. (2012), focusing on MIPAS (Michelson Interferometer for Passive Atmospheric Sounding) and ACE-FTS (Atmospheric Chemistry Experiment-Fourier Transform Spectrometer) data, respectively. Here we reassess the discrepancies based on newer MIPAS and ACE-FTS data sets, showing for completeness also results from SMR (Sub-Millimetre Radiometer) observations and a ECHAM/MESSy (European Centre for Medium-Range Weather Forecasts Hamburg/Modular Earth Submodel System) Atmospheric Chemistry (EMAC) simulation (Eichinger et al., 2015b). Similar to the old analyses, the MIPAS data sets yield a pronounced annual variation (maximum about 75‰) while that derived from the ACE-FTS data sets is rather weak (maximum about 25‰). While all data sets exhibit the phase progression typical for the tape recorder the annual maximum in the ACE-FTS data set precedes that in the MIPAS data set by 2 to 3 months. We critically consider several possible reasons for the observed discrepancies, focusing primarily on the MIPAS data set. We show that the δD annual variation in the MIPAS data is up to an altitude of 40hPa substantially impacted by a start altitude effect, i.e. dependency between the lowermost altitude where MIPAS retrievals are possible and retrieved data at higher altitudes. In addition, there is a mismatch in the vertical resolution of the MIPAS HDO and H2O data (being consistently better for HDO), which actually results in an artificial tape recorder-like signal in δD. Considering these MIPAS characteristics largely removes any discrepancies between the MIPAS and ACE-FTS data sets and confirms a δD tape recorder signal with an amplitude of about 25‰ in the lowermost stratosphere. [ABSTRACT FROM AUTHOR]

Optimal values of the effective viscosity and the stress jump coefficient in the Stokes-Brinkman model with continuous and jump stress conditions, respectively, have been accurately characterized and then applied to solve various two-dimensional transverse dual-scale flows in fibrous porous media. In this work, the effective viscosity and the stress jump coefficient are determined such that the interfacial slip velocity can be identified to that in the effective Navier-slip description and therefore it naturally facilitates the accurate prediction of the slip velocity and its gradient (stress) at the fluid/porous interface along with the velocity fields in both the porous media and the pure fluid domain. With these optimal values of the effective viscosity and the stress jump coefficient, the Stokes-Brinkman coupling can be employed to accurately describe the dual-scale porous flow at low computational cost, which may provide an effective computational framework in investigating particle deposition/filtration and void transports within composites. [ABSTRACT FROM AUTHOR]

Selective recording on multiple structures may be possible with microwave-assisted magnetic recording. The number of parameters in even a dual-structure system is such that optimization is difficult. In this paper, the response surface methodology is used to systematically optimize a dual-structure system. Optimized structures are presented for three different recording configurations, allowing random writes to either structure or writing in a predetermined order. The addition of a second structure could allow areal densities of over 3 Tbit/in2 to be achieved. [ABSTRACT FROM AUTHOR]

This paper compares different mechanisms of heat transport across nano-scale gaps and discusses the role of electromagnetic phenomena in heat transport in general nano-scale layered structures. The results of the analysis suggest that heat transfer across sub-5 nm gaps like that appearing in prototypes of heat assisted magnetic recording (HAMR) systems is dominated by direct intermolecular interactions between the separated bodies and is little affected by electromagnetic radiation. The analysis further suggests that local heating for HAMR with sub-5 nm spacing can be more efficiently achieved by a Joule heater that is simpler to fabricate than laser-based optical systems and is less destructive for the nano-scale transducers than laser radiation, which may lead to their structural damage and short duration life of nanoscale transducers. [ABSTRACT FROM AUTHOR]

In this study, we have developed secondary resonance magnetic force microscopy (SR-MFM) for imaging alternating magnetic fields from a sample surface at the secondary resonant frequency of the magnetic cantilever at the same time as the topographic image. SR-MFM images of alternating magnetic fields diverging from the main pole in a driving perpendicular magnetic recording head are presented, and the divergence and convergence of the fields are discussed. The spatial resolution of SR-MFM is estimated to be 18 nm; this is 2.5 times smaller than that of conventional MFM. [ABSTRACT FROM AUTHOR]