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In a 1988 study, a generalized non-linear SST algorithm was derived from the radiative transfer equation. An empirical approximation to this algorithm provided the simplified NLSST algorithm for computing sea surface temperatures with satellite radiometer data. It has remained a favorite of the remote sensing community for the past 25 years. However, a 1998 study demonstrated that the functional form of the generalized non-linear algorithm, which is here designated the GNLSST, is very much data dependent. In this paper we explore the various functional forms that the GNLSST may take. Rather than using actual satellite data, we model the effects of atmospheric absorption by water vapor, under saturation conditions, on the satellite split-window temperature difference, ΔT, in the 11–13 μm infra-red spectral region. The parameters used in the GNLSST algorithm are adjusted to demonstrate the various forms that the GNLSST can take. One key finding is that the familiar algorithms used for measuring SST, such as the MCSST, the NLSST and the QSST are all special solutions to the more general GNLSST algorithm. Additionally, the GNLSST may take other forms, which are described graphically. The simplifying assumptions which yield the NLSST solution represent an approximation to reality when working with actual satellite data. It is demonstrated that minor modifications to the regression procedures, which are used to derive the NLSST with satellite split-window data, may reduce the temperature errors resulting from these approximations. Alternative forms of the GNLSST algorithm may be useful for users of regional split-window satellite data.

Globally coral reefs have been declining at alarming rates as a result of anthropogenic stressors, leading to increased frequency and severity of widespread bleaching and disease events. These events are often associated with increased water temperatures due to climate change as well as regional and local stress from nutrient enrichment through runoff and sedimentation from coastal development. In late 2014, a white syndrome disease outbreak was reported off the coast of southeast Florida and was subsequently documented spreading throughout the region. This study examined the regional impacts of the disease event on the southeast Florida stony coral population utilizing stony coral demographic data from the Southeast Florida Coral Reef Evaluation and Monitoring Project (SECREMP). SECREMP is a long-term monitoring project examining 22 sites distributed from Miami-Dade County north to Martin County, Florida. The results revealed significant region-wide declines in stony coral diversity, density, and live tissue area corresponding with increased disease prevalence, which reached its maximum for the study period in 2016. Regional declines in coral density approached 30% loss and live tissue was upwards of 60% as a result of the disease outbreak. Additionally, multiple species were severely impacted, especially the reef building, complexity-contributing species Montastraea cavernosa, Meandrina meandrites, and Siderastrea siderea. The disease outbreak resulted in acute mortality and altered the ecosystem function to a point such that recovery is uncertain. This multiyear, region-wide disease outbreak has been indiscriminate relative to coral species impacted and was arguably the most devastating disturbance event documented on the Southeast Florida Reef Tract.

A 0.25-m2 quadrat sampler was constructed to collect microhabitat data for the Nashville crayfish (Orconectes shoupi) in the Mill Creek watershed, Nashville, Tennessee. Studies of other crayfish species have used a 1.00-m2 quadrat sampler; however, due to the requirement of precise measurement for microhabitat variables, we needed to enclose a smaller area. The 0.25-m2 quadrat sampler increased chances of capturing Nashville crayfish at precise points where microhabitat variables could easily be measured. Our sampler was 89% efficient at capturing crayfish under shallow (< 0.50 m deep) water conditions present during 2007 and provided precise microhabitat information that will be useful for preserving and recovering this species.

Sea-surface temperatures are computed operationally at the National Earth Satellite Service (NESS) of NOAA from a combination of AVHRR window channel data and HIRS-2 sounder data obtained from the NOAA-6 spacecraft. Datafrom one of the HIRS-2 water vapor channels, channel 11 centered at 7.33 ,um, is used to correct the AVHRR window channel measurement for atmospheric absorption by water vapor. Recent studies have demonstrated a considerable bias in accuracy between the winter and summer hemispheres in the mid-latitude and polar regions. It has been found that this bias is associated with a variation in the temperature lapse rate of the atmosphere between the hemispheres. An additional correction to the sea-surface temperature data based on lapse rate information obtained from the HIRS-2 instrument has resulted in a very considerable reduction of this bias.

The familiar linear multichannel sea surface temperature algorithms (MCSST) for estimating sea surface temperature with AVHRR satellite data describe the solution in terms of a constant gamma parameter multiplied by the measured brightness temperature difference of two of the window channels. A nonlinear algorithm is developed in this paper which is similar in form to the MCSST algorithm but with the gamma parameter having a specific two- or three-channel temperature dependence. Simulation studies show that the linear and nonlinear algorithms provide nearly identical accuracies for a wide range of atmospheric conditions if the satellite data are error free. When random or noncorrelative error sources are present in the multichannel AVHRR data, it is found that the nonlinear algorithms significantly reduce their effect upon the final solution relative to the linear MCSST solution. These results are verified with actual AVHRR data obtained in January-March 1982 and 1983. The algorithm estimates of ...

OVER a period of years many leaders in music education have docried the acarlemic stuffiness of some of the approaches to theory instruction. Author Walton is one of the sensitive musicians whose observations and practices must be welcomed by students to whom knowledge about the structure and components of music involves something more than geometrical and mathematical analysis of its anatomy. One editorial reader of this article stated that: “Even the introdiction of a paper which has the word ‘theory’ in its title forebodes dry and dismal literary landscape! Why not change the Walton title to something of more concord with the author's thought when he says: “The current trend is for the theory course to be broader in its scope, and to assume a more vital role in the music curriculum. In this broader concept, the term ‘theory’ seems most inadequate and narrow, and the term ‘musicianship’ is much more appropriate, since the development of musicianship is becoming the chief concern and core of theoretic study.”

It is a well-known fact that jacket crowns sometimes fracture from apparently nor­ mal use. The types of fractures— the longitudinal split of the crown and the crescent-shaped fracture in the labiogingival or linguogingival regions ■— are familiar to all dentists. The purpose of the present study was to determine the causes of such fractures by analyzing the regions of strain within jacket crowns subjected to a load. The external shape of the jacket is determined by tooth form and physio­ logical requirements, but the core or sup­ porting tooth substance can be modified within certain limits to achieve two essen­ tial requirements: stability and strength. I f the crown is to have stability, it must not rotate, twist or deform excessively under tooth loads. Stresses in the crown must be low enough to prevent fracture due to tooth loads. Obviously, the core design must be a compromise between the shapes de­ manded by the two requirements of sta­ bility and strength. From the standpoint of stability, a cross section of the core should be rectangular with sharp corners; but from the standpoint of strength, a cross section of the core should be round or oval-shaped or at least rectangular with generously beveled or rounded line angles. It was decided, therefore, that if a large plastic prototype of a jacket was loaded on an appropriate core and then sectioned, it would be possible by view­ ing the sections under polarized light to find the precise regions of detrimental strains. Certain changes in the shape of the core could then be made to reduce these strains and thus reduce the inci­ dence of fracture of jacket crowns.

The role of the American Society of Hospital Pharmacists in fostering the drug information movement is described, and the effects of clinical pharmacy practice on drug information centers are outlined. ASHP has been an early and consistent supporter of the pharmacists' role in providing drug information. In 1968 the Society adopted a statement that outlined the role and expected competencies of drug information specialists. Accreditation standards for specialized residencies in drug information practice were adopted in 1982. On a broad scale, drug information pharmacists foster rational drug therapy through input on pharmacy and therapeutics committees. In general, when decentralized drug distribution and clinical pharmacy services are implemented in a hospital, the number of questions asked of a drug information center decreases, but the type of question changes. Drug information pharmacists working with clinical pharmacists provide a communication system for providing other health-care practitioners with information necessary for optimal drug therapy in particular patients. To increase the efficiency of drug information centers, drug information pharmacists must incorporate computer technology into their practice sites.

• The records of 886 patients who had appendectomy performed by the same surgeons within a five-year period were used to contrast appendiceal stump inversion vs simple ligation. Our analysis contrasted inversion vs simple ligation techniques as related to postoperative complications, hospital stay, and pathologic diagnosis. Adhesions requiring repeated operation to relieve bowel obstruction occurred in five of 87 patients with acute gangrenous appendicitis treated by inversion. Of 106 patients with acute gangrenous appendicitis treated with simple ligation, postoperative obstruction developed in none. No other statistically significant differences existed between the two techniques. These data suggest that simple ligation is at least as good as and probably better than inversion of the appendiceal stump. (Arch Surg1988;123:689-690)

To the Editor.— Rupture of pacemaker batteries is rare. Mercury-zinc batteries, used to power early pacemakers, have largely been replaced because their warranties lasted only three years. We believe ours is the first reported case of spontaneous rupture of an implanted mercury-zinc pacemaker battery. Report of a Case.— A 62-year-old man who had a ventricular-inhibited demand pacemaker placed in August 1978 for complete heart block arrived at the emergency department complaining of sudden swelling and pain over the pacemaker site. At 2 AM the patient was awakened by what he described as an "explosion" in his chest. Physical examination showed an elderly man in mild distress. His vital signs were normal except for a temperature of 38 °C (101 °F). The pacemaker site was swollen and erythematous, and the overlying skin was warm. Physical examination showed no other remarkable findings. A chest x-ray film showed fragments outside the epoxy casing