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We develop ultraviolet (UV) light emitting diodes (LEDs) that operate in the sub-240 nm (far UVC) regime. The traditional limitations of high Al content AlGaN—the low light extraction efficiency due to transverse magnetic polarization and the poor doping efficiency—were overcome by using AlN:GaN short period superlattices (SPSLs) of varying compositions throughout almost the entire device structure. The quality of our molecular beam epitaxy process for growing SPSL devices was verified via transmission electron microscopy and x-ray diffraction—together, these demonstrate our capacity for growing high quality interfaces with a great deal of control over the thicknesses of each individual layer. Resistivity measurements of our SPSL were three times smaller than bulk AlGaN of similar composition due to the improved doping efficiency. Devices fabricated on 6 in. sapphire substrates showed uniform performance, leading to over 10 000 functional devices per wafer. Packaged diodes exhibited a peak wall plug efficiency of 0.55% and an output power of 1.7 mW when operated at peak efficiency. The devices had an operating life (70% initial power) of 2800 h (at 20 mA continuous wave). Additionally, they could be driven as high as 1 A, which resulted in a record for radiant flux of a far UVC LED grown on sapphire (17.4 mW). [ABSTRACT FROM AUTHOR]

We present a case of simultaneous second-stage Fowler–Stephens Orchiopexy (FSO) with microvascular testicular autotransplantation for cryptorchidism and in a patient with prune belly syndrome. At 5 months old, the patient underwent laparoscopic bilateral first-stage FSO with the right testicle located 1 cm from the liver and the left slightly more caudal. An ultrasound on postoperative Day 72 following second-stage FSO and microvascular autotransplantation showed patent testicular vasculature. Our experience shows that this combination technique is safe and effective to supercharge the testicle and augment collateral vessels if clinical suspicion for monotherapy failure is high. [ABSTRACT FROM AUTHOR]

Treatment of tumors in organs obscured by the ribs is a challenge for high-intensity focused ultrasound (HIFU) array. The ribs absorb the ultrasound beam’s energy causing the temperature of the ribs to rise, the beam to be distorted, and the focal heat deposition to be limited. The challenges presented by the ribs motivated the development of the limited power deposition (LPD) refocusing algorithm, which is capable of limiting the power deposition over the ribs while maximizing the energy deposition at the focus, thus achieving an efficient and safe ablation. In this article, a new iterative sparse LPD (ISLPD) approach that provides similar focal heating to previously developed methods while reducing the number of transducers excited during the HIFU treatment is discussed. It will be possible to conduct processes, such as imaging and motion tracking in parallel with the HIFU treatment by using the elements no longer used by the refocusing technique. The approach removes transducer elements by using an iteratively reweighted penalty matrix to achieve a more sparse solution over the course of multiple rounds of sparsity induction by harshly punishing the use of elements that previously had low excitation magnitudes. The semidefinite relaxation (SDR) method is used as a means of relaxing the nonconvex constraints into convex form and induces sparsity using the one-norm squared as a convex surrogate for the zero-norm. A 1-MHz spherical phased-array focused on a target in an inhomogeneous medium is simulated to test the algorithms’ efficacy. The propagation of the waves as they travel from the array toward the target was modeled using a finite-difference time-domain propagation model. Temperature simulations that utilized the inhomogeneous bioheat transfer equation (BHTE) were used to determine the temperature rise profile within the region of interest (ROI). These simulation results illustrate the benefits of the optimization-based approach proposed in this article over the ray-tracing (shadowing) method for element selection. [ABSTRACT FROM AUTHOR]

This essay explores the administrative and ideological context of Qing borderland pacification through examination of the imperial response to apex rebel ringleaders. Presented are five cases of bureaucratic "discourse" (official description and physical management) processing Lin Shuangwen (1786-1788 Lin Shuangwen Revolt), Shi Sanbao (1795-1797 Miao Revolt), Liu Zhixie (1796-1804 White Lotus Rebellion), Lin Qing (1813 Eight Trigrams Revolt), and Khoja Jahāngīr (1826-1828 Jahāngīr Uprising). Considered comparatively, we find common procedures of identification, deposition, sentencing, and execution that established the challengers as "men of iniquity," reinforcing imperially preferred understandings of rebel organization, culpability, Qing legitimacy, and martial success. This procedure was also adjusted to fit differing conditions and state goals. As the empire entered its final century, shifting boundaries were asserted between rebel lords and war-zone populations, suggestive of both military efforts to exploit social divisions and expanded embrace of peripheral peoples as compliant and border-defending imperial subjects. [ABSTRACT FROM AUTHOR]

The article focuses on the deterioration of the Qing dynasty from 1799 to 1820, focusing particularly on China's government policies in southern Shaanxi province after the White Lotus Revolt (1796-1804). The article argues that imperial policies regarding the frontier regions in Shaanxi were indicative of the handling of later 19th century crises. The article also discusses the Hans; Qinling mountains; the Daba Shan Range, or Greater Ba Mountains; the Han River valley area; Shaanxi's infrastructure, China's history and legends regarding Shaanxi, and Imperial Confucianism.

This essay examines an influential group of lower and middle level Qing administrators who served in southern Shaanxi in the early nineteenth century. These officials distinguished themselves pacifying the 1796-1804 White Lotus revolt, were promoted during the 1799-1805 Jiaqing reforms, and then were retained up to two decades in southern Shaanxi on the basis of their local expertise and effective administration. Accounts of rebel pacification, water management, and temple construction show that this cadre of field officials possessed considerable bureaucratic backing, regional prestige, and exibility in local action. These assets strengthened their ability to mobilize, supervise, restrain, and instruct increasingly self-managed local communities and aided the post-war restoration of southern Shaanxi. Their long tenure and regional authority likewise foreshadowed the rise of provincial "strongmen" in mid-nineteenth century China. [ABSTRACT FROM AUTHOR]

Focuses on the Yuelu Academy and Headmaster Luo Dian's contribution to statecraft, one of the most significant turns in the school's thousand-year history. Yuelu Academy historiography; Rise of the Yuelu Academy in the early and middle Qing; Overview of the academy in transition.

Chloral hydrate (along with other anaesthetics and hypnotics) is an inhibitor of cell division. We have shown that chloral hydrate is also an inhibitor of protein synthesis. This inhibition is unlikely to be a result either of the disruption of cell division or of interference with the function of microtubules. The ability of chloral hydrate to inhibit cell division may result from its ability to inhibit protein synthesis. [ABSTRACT FROM AUTHOR]

Melphalan-induced toxicity in nude mice following pretreatment with a regimen of L-buthionine sulfoximine (BSO), previously shown to enhance the activity of this alkylating agent against rhabdomyosarcoma and glioma xenografts, was examined. Mice were pretreated with i.p. BSO (2.5 mmol/kg x 7 doses at 12-h intervals plus concomitant availability of a 20-mM solution in the drinking water) or vehicle prior to a single i.p. injection of melphalan (35.65 mg/m2). As compared with control animals who received no BSO pretreatment, mice pretreated with BSO lost weight prior to therapy with melphalan (6.9% weight loss vs 0.3% weight gain; P less than 0.005) and showed a greater mean nadir weight loss after melphalan (3.8% vs. 2.1%; P = 0.049). Treatment with melphalan was associated with histologic evidence of reversible gastrointestinal toxicity, reversible myelosuppression, and histologic evidence of acute renal tubular necrosis, with no differences being observed between mice that had been pretreated with BSO and those that had been pretreated with vehicle. No evidence of cardiac, hepatic, or skeletal muscle toxicity was found in melphalan-treated animals. These results suggest that treatment of nude mice with melphalan following BSO-mediated depletion of glutathione does not result in enhanced organ toxicity despite an increase in the antineoplastic activity of this alkylating agent. [ABSTRACT FROM AUTHOR]