629 research outputs found
Advanced infrared laser modulator development
A parametric study was conducted to develop an electrooptic waveguide modulator for generating continuous tunable sideband power from an infrared CO2 laser. Parameters included were the waveguide configurations, microstrip dimensions device impedance, and effective dielectric constants. An optimum infrared laser modulator was established and was fabricated. This modulator represents the state-of-the-art integrated optical device, which has a three-dimensional topology to accommodate three lambda/4 step transformers for microwave impedance matching at both the input and output terminals. A flat frequency response of the device over 20 HGz or = 3 dB) was achieved. Maximum single sideband to carrier power greater than 1.2% for 20 W microwave input power at optical carrier wavelength of 10.6 microns was obtained
Pleasure Patents
The United States Patent and Trademark Office has granted thousands of patents for inventions whose purpose is to facilitate the sexual pleasure of their users. These pleasure patents raise a range of novel questions about both patent theory and the relationship between law and sexuality more broadly. Given that immoral inventions were long excluded from the patent system, and that sexual devices were widely criminalized for much of the past 150 years, how have patentees successfully framed the contributions of their sexual inventions? If a patentable invention must be both new and useful, how have patentees described the utility of sexual pleasure? This Article identifies several hundred patents that the USPTO has formally classified as improving sexual stimulation and intercourse, and it closely examines how patentees have described the utility of sexual pleasure over time. In describing the utility of technologies such as phalluses, vibrators, and virtual reality systems, patentees employ a diverse and rich set of themes about the purposes and social values of sexual pleasure. By facilitating sexual pleasure, these patented technologies can, according to their inventors: improve marital harmony, overcome female frigidity, calm fears of HIV transmission, reduce sexual assault, suppress demand for sex work, minimize the loneliness of single people, facilitate LGBTQIA relationships, and promote the emotional well-being of people with disabilities. As social and sexual norms have changed over time, so too have the various explanations for the social value of pleasure patents. This Article shows that the patent system is an underappreciated, and perhaps unexpected, archive of historical and contemporary sexual norms
Pleasure Patents
The United States Patent and Trademark Office has granted thousands of patents for inventions whose purpose is to facilitate the sexual pleasure of their users. These “pleasure patents” raise a range of novel questions about both patent theory and the relationship between law and sexuality more broadly. Given that “immoral” inventions were long excluded from the patent system, and that sexual devices were widely criminalized for much of the past 150 years, how have patentees successfully framed the contributions of their sexual inventions? If a patentable invention must be both new and useful, how have patentees described the utility of sexual pleasure? This Article identifies several hundred patents that the USPTO has formally classified as improving sexual stimulation and intercourse, and it closely examines how patentees have described the utility of sexual pleasure over time. In describing the utility of technologies such as phalluses, vibrators, and virtual reality systems, patentees employ a diverse and rich set of themes about the purposes and social values of sexual pleasure. By facilitating sexual pleasure, these patented technologies can, according to their inventors: improve marital harmony, overcome female frigidity, calm fears of HIV transmission, reduce sexual assault, suppress demand for sex work, minimize the loneliness of single people, facilitate LGBTQIA relationships, and promote the emotional well-being of people with disabilities. As social and sexual norms have changed over time, so too have the various explanations for the social value of pleasure patents. This Article shows that the patent system is an underappreciated, and perhaps unexpected, archive of historical and contemporary sexual norms
MUTANTS OF NONPRODUCER CELL LINES TRANSFORMED BY MURINE SARCOMA VIRUSES : I. INDUCTION, ISOLATION, PARTICLE PRODUCTION, AND TUMORIGENICITY
A variety of cell mutants were obtained by a single 5'-bromodeoxyuridine (BrdU) treatment of an nonproducer (NP) cell line transformed by the Kirsten strain of murine sarcoma virus (Ki-MSV). Isolation procedures of these cell See PDF for Structure mutants are described. The cell mutants obtained were classified by tumorigenic potential and shedding of Type C virus particles. The cell mutants were classified into four groups: (A) tumorigenic, without particles; (B) tumorigenic, with Type C particles; (C) nontumorigenic, without particles; and (D) nontumorigenic, with Type C particles. The tumorigenic cell lines showed variability in morphology with both flat and typical transformed appearing cell lines showing equal transplantability
Specificity of the DNA Product of RNA-Dependent DNA Polymerase in Type C Viruses: II. Quantitative Analysis
MUTANTS OF NONPRODUCER CELL LINES TRANSFORMED BY MURINE SARCOMA VIRUS : III. DETECTION AND CHARACTERIZATION OF RNA SPECIFIC FOR HELPER AND SARCOMA VIRUSES
BALB/3T3 cells transformed by the Kirsten sarcoma virus (nonvirus producer BALB/3T3 cells) and mutant cell lines derived therefrom by treatment with bromodeoxyuridine (BrdU) were analyzed for expression of virus-specific RNA using single-stranded DNA transcripts of Rauscher leukemia virus (RLV), a virus activated in one of the cell lines (58-2T), and Ki-SV-specific DNA transcript; the latter transcript after removal of all sequences cross-reactive with RLV RNA. The Rauscher virus DNA detected multiple copies of viral RNA in virus-producing cells (∼2.5 x 103/cell) whether infected with RLV or activated to produce virus with BrdU. Nonproducer (NP) cells and normal BALB cells showed small numbers of RNA genomes (70–250/cell) and only partial saturation of the transcript. The intracellular RNA sedimented at 35S (main peak) with a variable minor peak at 20S with the exception of one mutant cell, M-43-2 (main peak at 26–27S). The 58-2T transcript reacted preferentially in NP cells and their derivatives with biphasic kinetics suggesting the possibility of sequences specific for the original transforming virus. The size of Ki-SV specific sequences were 30S in mutant cells whether or not complete virus was being produced and independent of in vivo transplantability
MUTANTS OF NONPRODUCER CELL LINES TRANSFORMED BY MURINE SARCOMA VIRUS : II. RELATIONSHIP OF TUMORIGENICITY TO PRESENCE OF VIRAL MARKERS AND RESCUABLE SARCOMA GENOME
Tumorigenic and nontumorigenic mutants induced by a single 5'-bromodeoxyuridine (BrdU) treatment of a nonproducer (NP) tumorigenic cell line were isolated and characterized. Among the cloned derivatives were examples of virus-free and sarcoma virus-producing cell lines. Oncogenicity did not correlate with production of virus or ease of rescue of the sarcoma genome. All lines, including nononcogenic derivatives, retained the sarcoma genome. Phenotypic reversion of some cell mutants was observed after in vivo inoculation or long term in vitro cultivation. The M-50T cell line, obtained from a tumor induced by M-50 cells, had a sarcoma genome rescuable by direct superinfection; this was only achieved with parental M-50 cells by a cell fusion rescue technique. The M-43-2T cell, obtained from a single small static tumor induced by otherwise nononcogenic M-43-2 cells, shed sarcoma virus and became tumorigenic. M-58-4-48 became tumorigenic after passage 48 of the M-58-4 line, which was originally nontumorigenic. These observations of phenotypic reversion demonstrate that the presence of the sarcoma gene in cells is an essential but not sufficient condition of tumorigenesis
Simple model for 1/f noise
We present a simple stochastic mechanism which generates pulse trains
exhibiting a power law distribution of the pulse intervals and a
power spectrum over several decades at low frequencies with close to
one. The essential ingredient of our model is a fluctuating threshold which
performs a Brownian motion. Whenever an increasing potential hits the
threshold, is reset to the origin and a pulse is emitted. We show that
if increases linearly in time, the pulse intervals can be approximated
by a random walk with multiplicative noise. Our model agrees with recent
experiments in neurobiology and explains the high interpulse interval
variability and the occurrence of noise observed in cortical
neurons and earthquake data.Comment: 4 pages, 4 figure
Formation of Small-Scale Condensations in the Molecular Clouds via Thermal Instability
A systematic study of the linear thermal instability of a self-gravitating
magnetic molecular cloud is carried out for the case when the unperturbed
background is subject to local expansion or contraction. We consider the
ambipolar diffusion, or ion-neutral friction on the perturbed states. In this
way, we obtain a non-dimensional characteristic equation that reduces to the
prior characteristic equation in the non-gravitating stationary background. By
parametric manipulation of this characteristic equation, we conclude that there
are, not only oblate condensation forming solutions, but also prolate solutions
according to local expansion or contraction of the background. We obtain the
conditions for existence of the Field lengths that thermal instability in the
molecular clouds can occur. If these conditions establish, small-scale
condensations in the form of spherical, oblate, or prolate may be produced via
thermal instability.Comment: 16 page, accepted by Ap&S
Shoulder pain due to cervical radiculopathy: an underestimated long-term complication of herpes zoster virus reactivation?
Purpose
To evaluate if herpes zoster virus (HZV) reactivation may be considered in the aetiology of cervical radiculopathy.
Methods
The study group was composed of 110 patients (52 M-58F;mean age ± SD:46.5 ± 6.12; range:40-73) with a clinical diagnosis of cervical radiculopathy. Patients with signs of chronic damage on neurophysiological studies were submitted to an X-ray and to an MRI of the cervical spine in order to clarify the cause of the cervical radiculopathy and were investigated for a possible reactivation of HZV; HZV reactivation was considered as “recent” or “antique” if it occurs within or after 24 months from the onset of symptoms, respectively. Data were submitted to statistics.
Results
Thirty-eight patients (34,5%,16 M-22F) had a history of HZV reactivation: four (2 M-2F) were “recent” and 34 (14 M-20F) were “antique”. In 68 of 110 participants (61,8%,30 M-38F), pathological signs on X-ray and/or MRI of the cervical spine appeared; in the remaining 42 (38,2%,22 M-20F) X-ray and MRI resulted as negative. Among patients with HZV reactivation, seven (18,4%) had a “positive” X-ray-MRI while in 31 (81,6%) the instrumental exams were considered as negative. The prevalence of “antique” HZV reactivations was statistically greater in the group of patients with no pathological signs on X-ray/MRI of the cervical spine with respect to the group with a pathological instrumental exam (p < 0.01).
Conclusions
It may be useful to investigate the presence of a positive history of HZV reactivation and to consider it as a long-term complication of a cervical root inflammation especially in patients in which X-ray and MRI of the cervical spine did not show pathological findings
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