Design and analysis of optically pumped submillimeter waveguide maser amplifiers and oscillators

The design and experimental measurements are described of an optically pumped far-infrared (FIR) waveguide maser; preliminary measurements on a FIR waveguide amplifier are presented. The FIR maser was found to operate satisfactorily in a chopped CW mode using either methanol (CH3OH) or acetonitrile (CH3CN) as the active molecule. Two other gases, difluoroethane and difluoroethylene, produced an unstable output with high threshold and low output power when operated in the chopped CW mode. Experimental measurements include FIR output versus cavity length, output beam pattern, output power versus pressure, and input power. The FIR output was the input to an amplifier which was constructed similar to the oscillator. An increase of 10% in output power was noted on the 118.8 microns line of methanol

Understanding K-Pop Twitter as a site of Transnational Social Media Activism

This project aims to examine social media as a platform for political organization and social change beyond geographical boundaries in the context of K-pop fans and their transnational online communities. Social media, and twitter specifically, have long been a site of activism and popular music has always had a place in social commentary. In this paper, I seek to understand this phenomenon in the context of the large and ever-growing global community of Korean pop fans. In 2020, largely through the Black Lives Matter movement, we have seen, to the shock of many, a rise in political engagement from the K-pop fan community in a number of highly sensationalized events. Using data collected from twitter I will study the expressive sentiments and strategic organization of this population as well as how said action is perceived and engaged with by the media and general public. Additionally, I will study the transnational networks that facilitate this communal activism and the cross-cultural communication required for this level of organizational success and notoriety. My findings expose how, similar to other twitter-based New Social Movements, K-pop community action consists largely of expressive content with consistent efforts by ingroup members to define and monitor the scope of the movement and the rules of engagement. I note the importance of individual accounts with large spheres of influence in creating important community structures for content dissemination. I observe that, in these fan communities, actual transnational mobilization requires very little explicit instruction as these networks were built on shared affinity and thus have built in expectations of mutual aid. In the context of all of my findings, I reaffirm the importance of studying critically social media based community action and the positive as well as negative processes it can represent

Levels of Differentiation of Self in Married Couples

The construct of differentiation of self, a key concept in the family theory of Murray Bowen, is examined with the purpose of testing Bowen\u27s hypothesis that married couples are differentiated to the same degree. The Differentiation of Self Scale was used with 45 recently married couples from St. Louis County ranging in age from 20 to 71. Results of this study demonstrate that there is no significant correlation between the wives\u27 and husbands\u27 scores

Analysis and design of optically pumped far infrared oscillators and amplifiers

A waveguide laser oscillator was designed and experimental measurements made of relationships among output power, pressure, pump power, pump frequency, cavity tuning, output beam pattern, and cavity mirror properties for various active gases. A waveguide regenerative amplifier was designed and gain measurements were made for various active gases. An external Fabry-Perot interferometer was fabricated and used for accurate wavelength determination and for measurements of the refractive indices of solids transparent in the far infrared. An electronic system was designed and constructed to provide an appropriate error signal for use in feedback control of pump frequency. Pump feedback from the FIR laser was decoupled using a vibrating mirror to phase modulate the pump signal

Hybrid Palliation for Neonates With Hypoplastic Left Heart Syndrome: Current Strategies and Outcomes

In the last decade the hybrid procedure has emerged as an alternative stage I palliation in neonates with hypoplastic left heart syndrome (HLHS). This review discusses the historical aspect, surgical and interventional techniques, current outcomes and future direction of this procedure. Hybrid palliation yields equivalent but not superior stage I palliation survival and comparable 1-year survival to conventional Norwood palliation, comparable prestage II hemodynamics and pulmonary artery growth, and preserved ventricular function in stage II palliation. Hybrid palliation utilizes significantly less resource and shortens postoperative recovery. In comprehensive stage II palliation the impact of pulmonary artery reconstruction on subsequent pulmonary artery growth has not been determined and should be further investigated. A prospective, randomized trial is warranted to compare these two surgical strategies for neonates with hypoplastic left heart syndrome

Assessing Global Surface Water Inundation Dynamics Using Combined Satellite Information from SMAP, AMSR2 and Landsat

A method to assess global land surface water (fw) inundation dynamics was developed by exploiting the enhanced fw sensitivity of L-band (1.4 GHz) passive microwave observations from the Soil Moisture Active Passive (SMAP) mission. The L-band fw (fw(sub LBand)) retrievals were derived using SMAP H-polarization brightness temperature (Tb) observations and predefined L-band reference microwave emissivities for water and land endmembers. Potential soil moisture and vegetation contributions to the microwave signal were represented from overlapping higher frequency (Tb) observations from AMSR2. The resulting (fw(sub LBand)) global record has high temporal sampling (1-3 days) and 36-km spatial resolution. The (fw(sub LBand)) annual averages corresponded favourably (R=0.84, p<0.001) with a 250-m resolution static global water map (MOD44W) aggregated at the same spatial scale, while capturing significant inundation variations worldwide. The monthly (fw(sub LBand)) averages also showed seasonal inundation changes consistent with river discharge records within six major US river basins. An uncertainty analysis indicated generally reliable (fw(sub LBand)) performance for major land cover areas and under low to moderate vegetation cover, but with lower accuracy for detecting water bodies covered by dense vegetation. Finer resolution (30-m) (fw(sub LBand)) results were obtained for three sub-regions in North America using an empirical downscaling approach and ancillary global Water Occurrence Dataset (WOD) derived from the historical Landsat record. The resulting 30-m (fw(sub LBand)) retrievals showed favourable spatial accuracy for water (70.71%) and land (98.99%) classifications and seasonal wet and dry periods when compared to independent water maps derived from Landsat-8 imagery. The new (fw(sub LBand)) algorithms and continuing SMAP and AMSR2 operations provide for near real-time, multi-scale monitoring of global surface water inundation dynamics and potential flood risk

Double shunt technique for hybrid palliation of hypoplastic left heart syndrome: a case report

We report a technique to palliate hypoplastic left heart syndrome, with no PDA stenting, but with double polytetrafluoroethylene shunt from pulmonary artery to ascending and descending aorta by combined thoracotomies. A 30-day-old female was operated with this technique. Five months after first operation, the child was submitted to Norwood/Glenn operation. Good hemodinamic recovery and initial clinical evolution was observed. The child was extubated in 8th post operatory day and reentubated in the next day due to pulmonary infection. Despite antibiotic treatment, the child died after systemic infectious complications