Optics research at the U.S. Army Research Laboratory.

The U.S. Army Research Laboratory (ARL) is the Army's premier laboratory for land forces. The Army relies on ARL for scientific discoveries, technological advances, and analyses that enable capabilities a future Army will need to persevere over adversaries. Although a relatively young organization that will celebrate 25 years of the discovery, innovation, and transition of science and technology in October 2017, ARL has already had significant impact in a wide range of scientific and technological disciplines. In this paper, we highlight some of its past and recent achievements in optics and photonics.

Failure of the urinalysis and quantitative urine culture in diagnosing symptomatic urinary tract infections in patients with long-term urinary catheters.

Since urine culture and urinalysis are both of uncertain reliability in diagnosing symptomatic urinary tract infections in patients with chronic urinary catheters, we performed sequential quantitative cultures and urinalyses on 177 urine specimens from 14 patients with long-term urinary catheters during a 12-month period. We found high concentrations of greater than or equal to 2 species of aerobic bacteria or fungi in most specimens examined. Pyuria was common even during asymptomatic periods; hematuria was less common. During symptomatic urinary tract infections, neither urinalyses nor quantitative urine cultures exhibited changes specific for such infections. Thus neither urinalysis nor urine culture appears to be a reliable test for symptomatic urinary tract infections in patients with chronic urinary catheters.

A patch-graft technique for correction of pulmonic stenosis in dogs.

Pulmonic stenosis in 6 dogs were corrected surgically by means of a patch-graft technique, without using cardiac bypass or venous occlusion. Five of the 6 dogs have remained clinically normal for 4 to 40 months following surgery. The stenosis in 1 dog was inadequately repaired. The technique resulted in minimal blood loss, no mortality, and was easily adapted to the minimal size of several of the affected dogs. When performed correctly, the technique relieved the stenosis wherever it occurred (viz, supravalvular, valvular, subvalvular, infundibular, or any combination). The success of the procedure was determined, in part, by pre- and postoperative pressure measurements at the time of surgery, and by periodic physical, radiographic, and electrocardiographic examinations after surgery.

Disseminated aspergillosis in a dog.

A dog with disseminated Aspergillus terreus infection died after a protracted course of hospitalization. Treatment with amphotericin B methyl ester was without effect. The causative organism was found in bone, myocardium, spleen, kidneys, liver, thymus, lymph nodes, and both eyes. Treatment with antimicrobials and corticosteroids prior to hospitalization may have contributed to dissemination of the fungus.

Planning and implementing a research project: Part 2.

This article is the second in a series of three focused on steps in the development of a research proposal. This second article presents the steps of research design, sampling, data collection procedures, and types of data collection instruments. The discussion of the steps focuses the reader on helpful hints pertinent to each step. Additional references are provided for a more detailed discussion of the process.

Planning and implementing a research project: Part 1.

This article is the first in a series of three focused on the steps in the development of a research proposal. This first article presents the beginning steps of identification of a problem, statement of the research question and hypotheses, and review of the literature. The series of articles is meant to provide an overview of how to accomplish each of the steps. The discussion of the steps focuses the reader on helpful hints pertinent to each step. Additional references are provided for a more in-depth discussion of the process.

Optically pumped CD3F submillimeter-wave laser.

Submillimeter-wave laser action is reported for the first time in fully deuterated methyl fluoride. Twelve new laser lines were obtained by optical pumping with twelve CO(2) laser lines in the 9- and 10-microm regions. Milliwatt-level cw lasing was observed on two lines in an unoptimized hole-coupled waveguide resonator.

Image transfer by mutually pumped phase conjugators.

Cross talk is observed during the transient time of the photorefractive grating formation in a mutually pumped phase conjugator. We show that this feature can be used to transfer pictorial information from one location to another. The transfer is instantaneous and is demonstrated at a resolution of 6 lines/mm.

Edge enhancement of a phase-conjugate image with a mutually pumped phase conjugator.

Usually edge enhancement of optical images is produced by introduction of loss into the low spatial frequency components of the image-bearing beam in the Fourier plane of a lens. We report on edge-enhanced phase-conjugate images from a mutually pumped conjugator accomplished by spatial filtering in the Fraunhofer diffraction region of the input beams. High-resolution (128-160 lines/mm) edge-enhanced images are obtained through traditional spatial filtering in the Fourier plane and in the Fraunhofer regime. Amplification of these edge-enhanced images is observed with some loss of high spatial resolution (50 lines/mm).

Intraoperative use of inhaled PGI(2) for acute pulmonary hypertension and right ventricular failure.

Inhaled prostacyclin (PGI(2)) can be used as an effective pulmonary vasodilator intraoperatively to treat pulmonary hypertension and impending right ventricular failure.