Comparison of the eye's wave-front aberration measured psychophysically and with the Shack-Hartmann wave-front sensor

The Shack-Hartmann wave-front sensor offers many theoretical advantages over other methods for measuring aberrations of the eye; therefore it is essential that its accuracy be thoroughly tested. We assessed the accuracy of a Shack-Hartmann sensor by directly comparing its measured wave-front aberration function with that obtained by the Smirnov psychophysical method for the same eyes. Wave-front profiles measured by the two methods agreed closely in terms of shape and magnitude with rms differences of approximately lambda/2 and approximately lambda/6 (5.6-mm pupil) for two eyes. Primary spherical aberration was dominant in these profiles, and, in one subject, secondary coma was opposite in sign to primary coma, thereby canceling its effect. Discovery of an unusual, subtle wave-front anomaly in one individual further demonstrated the accuracy and sensitivity of the Shack-Hartmann wave-front sensor for measuring the optical quality of the human eye.     

Quality of care problems among Medicare and Medicaid patients

The purpose of this study was to characterize quality of care problems among Medicare and Medicaid inpatients in New York State. The patients selected for this study comprised 1991 and 1992 Medicare and all 1992 Medicaid inpatients in whom quality of care problems with actual or potential adverse effects were found. The patients in this study were drawn from public, proprietary, voluntary and teaching hospitals. A total of 1000 quality of care problems with either actual or potential adverse effects were found in 706 Medicare patients. Two hundred and seventy-five (275) quality of care problems with actual or potential adverse effects were found in 154 Medicaid patients. Premature death occurred in 53 (7.4%) of the 706 Medicare and in 42 (27.2%) of the 154 Medicaid patients. Treatment problems and monitoring failures accounted for the majority of quality of care problems with actual or potential adverse effects for both Medicare (63.0%) and Medicaid (75.7%) patients. Among Medicare patients, the treatment of infections and antibiotic use, fluid and electrolyte management, and inappropriate drug use were among the leading causes of quality of care problems. Attending physicians were associated with the majority of Medicare quality of care problems while house staff and attending physicians were associated with the majority of those among Medicaid patients. The results of this study indicate that there are several leading causes of quality of care problems among Medicare and Medicaid patients. Treatment problems and monitoring failures together comprise the majority of such problems. Among Medicare patients, it was found that most quality of care problems were associated with the treatment of infections and antibiotic use, fluid and electrolyte management, and inappropriate drug use. Most quality of care problems among Medicaid patients were associated with these categories as well as with labor and delivery problems, and poor discharge planning. The results of this study reflect the peer-review process in which providers are given an opportunity to respond to physician-reviewer decisions about the presence of actual or potential adverse effects. Such a process, which permits the presentation of additional data and information by providers, produces fewer final adverse outcome determinations than a process uniquely based on chart review. The quality of care problems observed in this study are amenable to focused educational interventions. Such remedial interventions could yield significant improvements in the quality of care for all patients.     

Full expression of the exaggerated salt appetite of the spontaneously hypertensive rat requires a prenatal factor

1. The spontaneously hypertensive rat (SHR) exhibits a lower bodyweight in utero and an exaggerated salt appetite post partum. To determine whether salt appetite is affected by the perinatal environment, we measured the salt appetite of embryo-cross-transferred SHR and Wistar Kyoto (WKY) rats at maturity. 2. One-cell embryos were collected from the oviducts of donor rats and transferred into the oviducts of recipients through the infundibulum. The salt appetite of the resultant female offspring for 0.10 and 0.15 mol/L saline was measured at 20-30 weeks of age. 3. Salt intake of SHR gestated in WKY rats was significantly lower than that of SHR gestated in SHR, while that of WKY rats gestated in SHR was higher than that of WKY rats gestated in WKY rats. 4. Therefore, some maternal factor plays a role in the development of the exaggerated salt appetite of the SHR. This factor is also able to affect the later salt appetite of WKY rat offspring born to SHR surrogates.     

Research bronchoscopies do not adversely affect HIV-infected individuals' future health-care decisions

STUDY OBJECTIVES: Asymptomatic HIV-infected individuals are increasingly recruited for studies involving invasive procedures such as bronchoscopy. We sought to determine the response to and outcome of a request for a research bronchoscopy in HIV-positive individuals with no respiratory disease, and whether this would adversely affect future decisions to have a medically indicated bronchoscopy. DESIGN AND SETTING: Prospective, semistructured, questionnaire-based study in a London teaching hospital HIV outpatient clinic. PARTICIPANTS: One hundred and seven consecutive HIV-infected eligible individuals. Thirty-one healthy volunteers served as a control group for the subjective response to bronchoscopy. MAIN OUTCOME MEASURES: Subjects' attitudes and responses to requests for bronchoscopy and subsequent behavior when they required medically indicated bronchoscopy. RESULTS: Seventy-five patients (70%) agreed to the procedure in principle, predominantly for altruistic reasons. Thirty-nine subjects underwent bronchoscopy. Five percent found it worse than expected; and 79% agreed to another research bronchoscopy (performed in 11 subjects approximately 2 years later). All patients said they would undergo bronchoscopy again for diagnostic purposes (required in seven during the study). When compared to a healthy volunteer population within the same study, postbronchoscopy symptoms were similar in frequency although somewhat different in nature. Subjects felt that a clear explanation of what was involved enhanced their participation in this research. CONCLUSIONS: Invasive research procedures such as bronchoscopy can be performed and are repeatable in a healthy HIV-infected population. Performance of procedures for research purposes does not appear to adversely affect future health-care decisions.     

Automatic reconstruction of as-built building information models from laser-scanned point clouds: A review of related techniques

Building information models (BIMs) are maturing as a new paradigm for storing and exchanging knowledge about a facility. BIMs constructed from a CAD model do not generally capture details of a facility as it was actually built. Laser scanners can be used to capture dense 3D measurements of a facility's as-built condition and the resulting point cloud can be manually processed to create an as-built BIM — a time-consuming, subjective, and error-prone process that could benefit significantly from automation. This article surveys techniques developed in civil engineering and computer science that can be utilized to automate the process of creating as-built BIMs. We sub-divide the overall process into three core operations: geometric modeling, object recognition, and object relationship modeling. We survey the state-of-the-art methods for each operation and discuss their potential application to automated as-built BIM creation. We also outline the main methods used by these algorithms for representing knowledge about shape, identity, and relationships. In addition, we formalize the possible variations of the overall as-built BIM creation problem and outline performance evaluation measures for comparing as-built BIM creation algorithms and tracking progress of the field. Finally, we identify and discuss technology gaps that need to be addressed in future research.     

T-lymphocytes from AIDS patients are unable to synthesize ribonucleotides de novo in response to mitogenic stimulation. Impaired pyrimidine responses are already evident at early stages of HIV-1 infection

Proliferative defects have been reported at the level of DNA synthesis, even in T-lymphocytes from asymptomatic human immunodeficiency virus type-1+ (HIV-1+) patients. Since purine and pyrimidine ribonucleotide availability is crucial for proliferation, we compared the ability of HIV-1- and HIV-1+ T-lymphocytes (> 95% CD4+ and CD8+) to activate de novo biosynthetic and salvage pathways following phytohemagglutinin stimulation using 14C-labeled precursors. The striking abnormality already detectable in asymptomatic patients' cells was the impaired ability of CTP, UDP-Glc, and UTP pools to expand over 72 h (44-70% of control), although ATP and GTP pools and responses were normal. In symptomatic patients, resting T-cells showed markedly reduced pyrimidine pools (53-74% of control) with no change following activation. Relatively normal ATP, GTP, and NAD pools masked the same impaired response of de novo synthesis to activation, with ATP and GTP being reduced by 50% at 48 h. Purine salvage was more active than the control in unstimulated HIV-1+ cells. This impaired de novo synthesis in HIV-1+ T-lymphocytes severely restricts the availability of ribonucleotides for vital growth-related activities such as membrane expansion and strand break repair as well as DNA and RNA synthesis. The data indicate that resting T-lymphocytes from symptomatic patients survive through enhanced salvage, but the stimulation induces metabolic cell death, and provide an explanation for the activation-associated lymphocyte death seen in HIV-1+ T-lymphocytes.     

Identification of potent inhibitors of Plasmodium falciparum plasmepsin II from an encoded statine combinatorial library

An encoded 13,020-member combinatorial library was synthesized containing a statine core. Evaluation of this library with plasmepsin II, an aspartyl protease required for hemoglobin metabolism in the malaria parasite, led to the identification of potent and selective inhibitors as well as novel structure-activity relationships.     

Inhibitory effect on LPS-induced tumor necrosis factor in calves treated with chlorpromazine or pentoxifylline

The inhibitory effect of chlorpromazine (CPZ), pentoxifylline (PTX) and dexamethasone (DEX) was investigated in a model of endotoxin shock in Holstein calves following an intravenous administration of Esherichia coli endotoxin (LPS). Initial correlations with its effects on the levels of tumor necrosis factor (TNF), a pivotal mediator of endotoxin shock, and clinical signs were obtained. The pretreatment of CPZ or DEX significantly decreased the serum levels of TNF, and reduced endotoxic shock. But the pretreatment of PTX hardly reduced the increase of serum TNF levels and endotoxin shock. The levels of serum endotoxin were not significantly different a minute of postinjection of LPS in calves. The results of this study indicate that pretreatment of CPZ or DEX inhibit various biological effects on endotoxin in calves.