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1.
Front Psychol ; 14: 1081086, 2023.
Article in English | MEDLINE | ID: mdl-37051611

ABSTRACT

Trust exerts an impact on essentially all forms of social relationships. It affects individuals in deciding whether and how they will or will not interact with other people. Equally, trust also influences the stance of entire nations in their mutual dealings. In consequence, understanding the factors that influence the decision to trust, or not to trust, is crucial to the full spectrum of social dealings. Here, we report the most comprehensive extant meta-analysis of experimental findings relating to such human-to-human trust. Our analysis provides a quantitative evaluation of the factors that influence interpersonal trust, the initial propensity to trust, as well as an assessment of the general trusting of others. Over 2,000 relevant studies were initially identified for potential inclusion in the meta-analysis. Of these, (n = 338) passed all screening criteria and provided therefrom a total of (n = 2,185) effect sizes for analysis. The identified dependent variables were trustworthiness, propensity to trust, general trust, and the trust that supervisors and subordinates express in each other. Correlational results demonstrated that a large range of trustor, trustee, and shared, contextual factors impact each of trustworthiness, the propensity to trust, and trust within working relationships. The emphasis in the present work on contextual factors being one of several trust dimensions herein originated. Experimental results established that the reputation of the trustee and the shared closeness of trustor and trustee were the most predictive factors of trustworthiness outcome. From these collective findings, we propose an elaborated, overarching descriptive theory of trust in which special note is taken of the theory's application to the growing human need to trust in non-human entities. The latter include diverse forms of automation, robots, artificially intelligent entities, as well as specific implementations such as driverless vehicles to name but a few. Future directions as to the momentary dynamics of trust development, its sustenance and its dissipation are also evaluated.

2.
Hum Factors ; 65(2): 337-359, 2023 Mar.
Article in English | MEDLINE | ID: mdl-34048287

ABSTRACT

OBJECTIVE: The present meta-analysis sought to determine significant factors that predict trust in artificial intelligence (AI). Such factors were divided into those relating to (a) the human trustor, (b) the AI trustee, and (c) the shared context of their interaction. BACKGROUND: There are many factors influencing trust in robots, automation, and technology in general, and there have been several meta-analytic attempts to understand the antecedents of trust in these areas. However, no targeted meta-analysis has been performed examining the antecedents of trust in AI. METHOD: Data from 65 articles examined the three predicted categories, as well as the subcategories of human characteristics and abilities, AI performance and attributes, and contextual tasking. Lastly, four common uses for AI (i.e., chatbots, robots, automated vehicles, and nonembodied, plain algorithms) were examined as further potential moderating factors. RESULTS: Results showed that all of the examined categories were significant predictors of trust in AI as well as many individual antecedents such as AI reliability and anthropomorphism, among many others. CONCLUSION: Overall, the results of this meta-analysis determined several factors that influence trust, including some that have no bearing on AI performance. Additionally, we highlight the areas where there is currently no empirical research. APPLICATION: Findings from this analysis will allow designers to build systems that elicit higher or lower levels of trust, as they require.


Subject(s)
Artificial Intelligence , Trust , Humans , Reproducibility of Results , Automation
3.
Regul Toxicol Pharmacol ; 123: 104933, 2021 Jul.
Article in English | MEDLINE | ID: mdl-33891999

ABSTRACT

Derivation of Predicted No Effect Concentrations (PNECs) for aquatic systems is the primary deterministic form of hazard extrapolation used in environmental risk assessment. Depending on the data availability, different regulatory jurisdictions apply application factors (AFs) to the most sensitive measured endpoint to derive the PNEC for a chemical. To assess differences in estimated PNEC values, two PNEC determination methodologies were applied to a curated public database using the EnviroTox Platform (www.EnviroToxdatabase.org). PNECs were derived for 3647 compounds using derivation procedures based on example US EPA and a modified European Union chemical registration procedure to allow for comparisons. Ranked probability distributions of PNEC values were developed and 5th percentile values were calculated for the entire dataset and scenarios where full acute or full chronic data sets were available. The lowest PNEC values indicated categorization based on chemical attributes and modes of action would lead to improved extrapolations. Full acute or chronic datasets gave measurably higher 5th percentile PNEC values. Algae were under-represented in available ecotoxicity data but drove PNECs disproportionately. Including algal inhibition studies will be important in understanding chemical hazards. The PNEC derivation logic flows are embedded in the EnviroTox Platform providing transparent and consistent PNEC derivations and PNEC distribution calculations.


Subject(s)
Hazardous Substances/toxicity , Toxicity Tests, Chronic/methods , Animals , Databases, Factual , Logic , No-Observed-Adverse-Effect Level , Probability , Risk Assessment , Water Pollutants, Chemical
4.
Ergonomics ; 60(5): 692-700, 2017 May.
Article in English | MEDLINE | ID: mdl-27267493

ABSTRACT

In this study, we examined how spatially informative auditory and tactile cues affected participants' performance on a visual search task while they simultaneously performed a secondary auditory task. Visual search task performance was assessed via reaction time and accuracy. Tactile and auditory cues provided the approximate location of the visual target within the search display. The inclusion of tactile and auditory cues improved performance in comparison to the no-cue baseline conditions. In comparison to the no-cue conditions, both tactile and auditory cues resulted in faster response times in the visual search only (single task) and visual-auditory (dual-task) conditions. However, the effectiveness of auditory and tactile cueing for visual task accuracy was shown to be dependent on task-type condition. Crossmodal cueing remains a viable strategy for improving task performance without increasing attentional load within a singular sensory modality. Practitioner Summary: Crossmodal cueing with dual-task performance has not been widely explored, yet has practical applications. We examined the effects of auditory and tactile crossmodal cues on visual search performance, with and without a secondary auditory task. Tactile cues aided visual search accuracy when also engaged in a secondary auditory task, whereas auditory cues did not.


Subject(s)
Acoustic Stimulation , Cues , Vibration , Adolescent , Adult , Attention , Discrimination, Psychological , Female , Humans , Male , Reaction Time , Task Performance and Analysis , Visual Perception , Young Adult
5.
Sci Rep ; 6: 25967, 2016 05 19.
Article in English | MEDLINE | ID: mdl-27193161

ABSTRACT

We have synthesized thermodynamically metastable Ca2IrO4 thin-films on YAlO3 (110) substrates by pulsed laser deposition. The epitaxial Ca2IrO4 thin-films are of K2NiF4-type tetragonal structure. Transport and optical spectroscopy measurements indicate that the electronic structure of the Ca2IrO4 thin-films is similar to that of Jeff = 1/2 spin-orbit-coupled Mott insulator Sr2IrO4 and Ba2IrO4, with the exception of an increased gap energy. The gap increase is to be expected in Ca2IrO4 due to its increased octahedral rotation and tilting, which results in enhanced electron-correlation, U/W. Our results suggest that the epitaxial stabilization growth of metastable-phase thin-films can be used effectively for investigating layered iridates and various complex-oxide systems.

6.
Neurobiol Dis ; 49: 232-46, 2013 Jan.
Article in English | MEDLINE | ID: mdl-22982711

ABSTRACT

Cortical malformations can cause intractable epilepsy, but the underlying epileptogenic mechanisms are poorly understood. We used high-speed glutamate biosensor imaging to ask how glutamatergic signaling is altered in cortical malformations induced by neonatal freeze-lesions (FL). In non-lesion neocortical slices from 2 to 8week old rats, evoked glutamate signals were symmetrical in the medio-lateral axis and monotonic, correlating with simple, brief (≈50ms) local field potentials (LFPs). By contrast, in FL cortex glutamate signals were prolonged, increased in amplitude, and polyphasic, which paralleled a prolongation of the LFP. Using glutamate biosensor imaging, we found that glutamate signals propagated throughout large areas of FL cortex and were asymmetric (skewed toward the lesion). Laminar analysis demonstrated a shift in the region of maximal glutamate release toward superficial layers in FL cortex. The ability to remove exogenous glutamate was increased within the FL itself but was decreased in immediately adjacent regions. There were corresponding alterations in astrocyte density, with an increase within the lesion and a decrease in deep cortical layers surrounding the lesion. These findings demonstrate both network connectivity and glutamate metabolism are altered in this cortical malformation model and suggests that the regional ability of astrocytes to remove released glutamate may be inversely related to local excitability.


Subject(s)
Cerebral Cortex/abnormalities , Cerebral Cortex/growth & development , Glutamic Acid/metabolism , Afferent Pathways/physiopathology , Animals , Animals, Newborn , Astrocytes/pathology , Astrocytes/physiology , Biosensing Techniques , Cerebral Cortex/physiopathology , Disease Models, Animal , Electric Stimulation , Female , Freezing/adverse effects , Immunohistochemistry , Male , Rats, Sprague-Dawley , Tissue Culture Techniques
7.
J Phys Condens Matter ; 22(33): 334224, 2010 Aug 25.
Article in English | MEDLINE | ID: mdl-21386514

ABSTRACT

We have studied how the hysteretic voltage-induced torsional strain, associated with charge-density-wave (CDW) depinning, in orthorhombic tantalum trisulfide depends on square-wave and triangle-wave voltages of different frequencies and amplitudes. The strains are measured by placing the sample, with a wire glued to the center as a transducer, in a radio frequency cavity and measuring the modulated response of the cavity. From the triangle waves, we map out the time dependence of the hysteresis loops, and find that the hysteresis loops broaden for waves with periods less than 30 s. The square-wave response shows that the dynamic responses to positive and negative voltages can be quite different. The overall frequency dependence is relaxational, but with multiple relaxation times which typically decrease with increasing voltage. The detailed dynamic response is very sample dependent, suggesting that it depends in detail on interactions of the CDW with sample defects.


Subject(s)
Nanostructures/chemistry , Nanostructures/ultrastructure , Sulfides/chemistry , Tantalum/chemistry , Elastic Modulus , Electromagnetic Fields , Macromolecular Substances/chemistry , Materials Testing , Molecular Conformation , Nonlinear Dynamics , Particle Size , Stress, Mechanical , Sulfides/radiation effects , Surface Properties , Tantalum/radiation effects , Torque
8.
Curr Med Res Opin ; 24(5): 1317-27, 2008 May.
Article in English | MEDLINE | ID: mdl-18377705

ABSTRACT

BACKGROUND: Current guidelines recommend the use of pH monitoring to confirm the diagnosis of acid reflux in patients with a normal endoscopy. This analysis evaluated the financial impact of pH monitoring with the wireless pH capsule on a managed care organization (MCO) in the United States. METHODS: A decision model was constructed to project total 1-year costs to manage GERD symptoms with and without the adoption of wireless pH capsules in a hypothetical MCO with 10 000 eligible adult enrollees, of whom 600 presented with GERD-like symptoms. Costs of GERD diagnosis, treatment, and symptom management for those in whom a GERD diagnosis was ruled out by pH monitoring were assessed. The incremental per-member-per-month (PMPM) and per-treated-member-per-month (PTMPM) costs were the primary outcomes. Data sources included literature, expert input, and standardized fee schedules. RESULTS: An increase of 10 percentage points in the use of pH monitoring with wireless pH capsules yielded incremental PMPM and PTMPM costs of $0.029 and $0.481, respectively. The costs of proton pump inhibitor (PPI) therapy to the plan dropped to $236,363 from $238,086, while increases were observed in pH monitoring (from $16 739 to $21 973) and non-GERD therapy costs (from $1392 to $1740). The results were sensitive to the percentage of patients requiring repeat endoscopy before wireless pH monitoring and the cost of PPIs. CONCLUSIONS: Timely and increased use of pH monitoring as recommended in published guidelines leads to less unnecessary use of PPIs with a modest budgetary impact on health plans.


Subject(s)
Cost of Illness , Esophageal pH Monitoring/economics , Gastroesophageal Reflux/diagnosis , Gastroesophageal Reflux/economics , Managed Care Programs/organization & administration , Proton Pump Inhibitors , Adult , Aged , Budgets , Cost-Benefit Analysis , Enzyme Inhibitors/administration & dosage , Enzyme Inhibitors/economics , Esophageal pH Monitoring/instrumentation , Esophagoscopy/economics , Female , Gastroesophageal Reflux/drug therapy , Humans , Male , Managed Care Programs/economics , Middle Aged , Models, Economic , Predictive Value of Tests , Proton Pumps/economics , Risk Assessment , United States
9.
Aquat Toxicol ; 87(2): 69-80, 2008 Apr 28.
Article in English | MEDLINE | ID: mdl-18339436

ABSTRACT

Concentration and time-dependent changes in hepatic gene expression were examined in adult, female zebrafish (Danio rerio) exposed to 0, 0.1, 0.7, 4.9 microg/L of a model androgen, 17alpha-methyldihydrotestosterone (MDHT). At 24 and 168 h, fish were sacrificed and liver was extracted for gene expression analysis using custom Affymetrix GeneChip Zebrafish Genome Microarrays. In an effort to link gene expression changes to higher levels of biological organization, blood was collected for measurement of plasma steroid hormones (17beta-estradiol (E2), testosterone (T)) and vitellogenin (VTG) using ELISA. Body and ovary weight were also measured. A significant reduction in E2 occurred at 24h (0.7 and 4.9 microg/L) and 168 h (4.9 microg/L) following MDHT exposure. In contrast, T was significantly increased at 24h (4.9 microg/L) and 168 h (0.1, 0.7, 4.9 microg/L). 171 and 575 genes were significantly affected in a concentration-dependent manner at either 24 or 168 h by MDHT exposure at p

Subject(s)
Dihydrotestosterone/analogs & derivatives , Gene Expression Profiling , Gene Expression Regulation/drug effects , Liver/drug effects , Oligonucleotide Array Sequence Analysis , Water Pollutants, Chemical/toxicity , Zebrafish/genetics , Animals , Dihydrotestosterone/toxicity , Environmental Exposure , Estradiol/blood , Female , Liver/metabolism , Ovary/drug effects , Reverse Transcriptase Polymerase Chain Reaction , Testosterone/blood , Vitellogenins/blood
10.
Phys Rev Lett ; 99(8): 086403, 2007 Aug 24.
Article in English | MEDLINE | ID: mdl-17930965

ABSTRACT

Solution-grown single crystals of Fe(2)OBO(3) were characterized by specific heat, Mössbauer spectroscopy, and x-ray diffraction. A peak in the specific heat at 340 K indicates the onset of charge order. Evidence for a doubling of the unit cell at low temperature is presented. Combining structural refinement of diffraction data and Mössbauer spectra, domains with diagonal charge order are established. Bond-valence-sum analysis indicates integer valence states of the Fe ions in the charge ordered phase, suggesting Fe(2)OBO(3) is the clearest example of ionic charge order so far.


Subject(s)
Iron , Spectroscopy, Mossbauer , Iron/chemistry , X-Ray Diffraction
11.
Aquat Toxicol ; 79(3): 233-46, 2006 Sep 12.
Article in English | MEDLINE | ID: mdl-16872691

ABSTRACT

Genomic, proteomic, and metabolomic technologies continue to receive increasing interest from environmental toxicologists. This interest is due to the great potential of these technologies to identify detailed modes of action and to provide assistance in the evaluation of a contaminant's risk to aquatic organisms. Our experimental model is the zebrafish (Danio rerio) exposed to reference endocrine disrupting compounds in order to investigate compound-induced changes in gene transcript profiles. Adult, female zebrafish were exposed to 0, 15, 40, and 100ng/L of 17alpha-ethynylestradiol (EE2) and concentration and time-dependent changes in hepatic gene expression were examined using Affymetrix GeneChip Zebrafish Genome Microarrays. At 24, 48, and 168h, fish were sacrificed and liver mRNA was extracted for gene expression analysis (24 and 168h only). In an effort to link gene expression changes to effects on higher levels of biological organization, body and ovary weights were measured and blood was collected for measurement of plasma steroid hormones (17beta-estradiol (E2), testosterone (T)) and vitellogenin (VTG) using ELISA. EE2 exposure significantly affected gene expression, GSI, E2, T, and VTG. We observed 1622 genes that were significantly affected (p< or =0.001) in a concentration-dependent manner by EE2 exposure at either 24 or 168h. Gene ontology (GO) analysis revealed that EE2 exposure affected genes involved in hormone metabolism, vitamin A metabolism, steroid binding, sterol metabolism, and cell growth. Plasma VTG was significantly increased at 24, 48, and 168h (p< or =0.05) at 40 and 100ng/L and at 15ng/L at 168h. E2 and T were significantly reduced following EE2 exposure at 48 and 168h. GSI was decreased in a concentration-dependent manner at 168h. In this study, we identified genes involved in a variety of biological processes that have the potential to be used as markers of exposure to estrogenic substances. Future work will evaluate the use of these genes in zebrafish exposed to weak estrogens to determine if these genes are indicative of exposure to estrogens with varying potencies.


Subject(s)
Ethinyl Estradiol/toxicity , Gene Expression Profiling/methods , Gene Expression/drug effects , Water Pollutants, Chemical/toxicity , Zebrafish/genetics , Animals , DNA Primers/chemistry , Down-Regulation/drug effects , Down-Regulation/genetics , Environmental Exposure , Estradiol/blood , Ethinyl Estradiol/analysis , Female , Liver/drug effects , Liver/physiology , Male , Reverse Transcriptase Polymerase Chain Reaction , Testosterone/blood , Up-Regulation/drug effects , Up-Regulation/genetics , Vitellogenins/blood
12.
Percept Psychophys ; 66(6): 970-87, 2004 Aug.
Article in English | MEDLINE | ID: mdl-15675645

ABSTRACT

In this study, we explore the conditions for accurate localization of vibrotactile stimuli presented to the abdomen. Tactile orientation systems intended to provide mobility information for people who are blind depend on accurate identification of location of stimuli on the skin, as do systems designed to indicate target positions in space or the status of remotely operated devices to pilots or engineers. The spatial acuity of the skin has been examined for simple touch, but not for the types of vibrating signals used in such devices. The ability to localize vibratory stimuli was examined at sites around the abdomen and found to be a function of separation among loci and, most significantly, of place on the trunk. Neither the structures underlying the skin nor the types of tactor tested appeared to affect localization. Evidence was found for anatomically defined anchor points that provide localization referents that enhance performance even with wide target spacing.


Subject(s)
Space Perception , Touch , Vibration , Abdomen , Adult , Female , Humans , Male
13.
Phys Rev Lett ; 90(11): 117003, 2003 Mar 21.
Article in English | MEDLINE | ID: mdl-12688957

ABSTRACT

The thermal conductivity kappa of the layered s-wave superconductor NbSe2 was measured down to T(c)/100 throughout the vortex state. With increasing field, we identify two regimes: one with localized states at fields very near H(c1) and one with highly delocalized quasiparticle excitations at higher fields. The two associated length scales are naturally explained as multiband superconductivity, with distinct small and large superconducting gaps on different sheets of the Fermi surface. This behavior is compared to that of the multiband superconductor MgB2 and the conventional superconductor V3Si.

14.
Int J Obes Relat Metab Disord ; 26(11): 1484-93, 2002 Nov.
Article in English | MEDLINE | ID: mdl-12439651

ABSTRACT

OBJECTIVE: Exercise is the cornerstone of behavioral weight loss programs. The total volume of exercise needed to both promote weight loss and elicit health benefits has not been sufficiently investigated. The aim of this study was to examine the effects of two different volumes of walking 'metabolic fitness' exercise prescriptions, in combination with a low-fat, ad libitum diet (LFAL) on weight loss and additional modifiable health-related variables (HRV) in an ethnically diverse sample of overweight premenopausal women. DESIGN: Clinical 12 week weight loss intervention study with a 5.0-5.8 MJ diet daily with (a). participants walking 30 min, 5 days per week (DEX1), (b). participants walking 60 min, five times per week (DEX2) or (c). a diet only control group (DO). SUBJECTS: A mixed racial sample (predominantly Hispanic) of 56 subjects (mean BMI=34.26+/-6.61, mean age= 39.45+/-7.34) completed the 12 week program. MEASUREMENTS: Various body weight, body composition and fat distribution variables, dietary intake and additional HRV such as blood lipids, blood pressure and an estimate of cardiorespiratory fitness at baseline and after 3 months. RESULTS: All groups showed similar and significant (P<0.001) declines in body weight, percentage body fat, BMI, WHR, fat mass, fat-free mass and diastolic blood pressure following the program. In addition, total cholesterol, triacylglycerol and the TC:HDL ratio displayed a significant time effect (P<0.05). Significant interactions (P<0.05) were found for waist circumference, sagittal diameter, estimated VO(2max) and LDL-C, with both exercise groups showing similar and significantly greater (P<0.05) improvements than DO. Significant interactions (P<0.05) were also observed for several dietary variables. CONCLUSION: Our study showed no dose-response effect of walking exercise on weight loss over diet alone. Both lower and higher volume metabolic fitness prescriptions resulted in similar and significant beneficial changes in several HRV. This data suggests that 30 min of walking on most days of the week may be as beneficial as 60 min (in combination with diet) in promoting numerous additional healthful outcomes over diet alone following a 12 week weight loss program.


Subject(s)
Exercise Therapy/methods , Obesity/rehabilitation , Walking , Weight Loss/physiology , Adipose Tissue , Adult , Analysis of Variance , Cholesterol, LDL/blood , Female , Humans , Obesity/blood , Obesity/diet therapy
15.
J Bacteriol ; 183(14): 4389-92, 2001 Jul.
Article in English | MEDLINE | ID: mdl-11418582

ABSTRACT

The complete Bacillus subtilis genome contains four genes (proG, proH, proI, and comER) with the potential to encode Delta(1)-pyrroline-5-carboxylate reductase, a proline biosynthetic enzyme. Simultaneous defects in three of these genes (proG, proH, and proI) were required to confer proline auxotrophy, indicating that the products of these genes are mostly interchangeable with respect to the last step in proline biosynthesis.


Subject(s)
Bacillus subtilis/enzymology , Genes, Bacterial , Proline/biosynthesis , Pyrroline Carboxylate Reductases/physiology , Arginase/metabolism , Mutagenesis , Pyrroline Carboxylate Reductases/genetics , delta-1-Pyrroline-5-Carboxylate Reductase
16.
Proc AMIA Symp ; : 359-63, 2001.
Article in English | MEDLINE | ID: mdl-11833479

ABSTRACT

This paper describes a study of the impact of Physician Order Entry (POE) on pharmacy order turn-around times. The study looked at two surgical services, Neurosurgery and Transplant, of a large Midwestern academic medical center. Pharmacy orders were followed in these units from the time a physician wrote an order to the time the patient received the medication. The first part of the study tracked pharmacy orders for a two-month period before the implementation of POE and the second part of the study tracked pharmacy orders for a two-month period after POE had been implemented. The pre- and post-POE pharmacy turn-around times were compared. It was expected that the data would show a substantial decrease in pharmacy order turn-around times. Our study did, in fact, show a significant reduction in this turn-around-time.


Subject(s)
Clinical Pharmacy Information Systems , Medication Systems, Hospital , User-Computer Interface , Humans , Medical Records Systems, Computerized , Time Factors
17.
Am Fam Physician ; 62(10): 2255-64, 2000 Nov 15.
Article in English | MEDLINE | ID: mdl-11126852

ABSTRACT

Anemia is a common problem that is often discovered on routine laboratory tests. Its prevalence increases with age, reaching 44 percent in men older than 85 years. Normocytic anemia is the most frequently encountered type of anemia. Anemia of chronic disease, the most common normocytic anemia, is found in 6 percent of adult patients hospitalized by family physicians. The goals of evaluation and management are to make an accurate and efficient diagnosis, avoid unnecessary testing, correct underlying treatable causes and ameliorate symptoms when necessary. The evaluation begins with a thorough history and a careful physical examination. Basic diagnostic studies include the red blood cell distribution width, corrected reticulocyte index and peripheral blood smear; further testing is guided by the results of these studies. Treatment should be directed at correcting the underlying cause of the anemia. A recent advance in treatment is the use of recombinant human erythropoietin.


Subject(s)
Anemia, Aplastic , Anemia, Hemolytic , Erythrocytes , Adult , Anemia, Aplastic/diagnosis , Anemia, Aplastic/etiology , Anemia, Aplastic/therapy , Anemia, Hemolytic/diagnosis , Anemia, Hemolytic/etiology , Anemia, Hemolytic/therapy , Child , Chronic Disease , Female , Humans , Middle Aged , Patient Education as Topic , Teaching Materials
18.
Development ; 127(17): 3855-64, 2000 Sep.
Article in English | MEDLINE | ID: mdl-10934029

ABSTRACT

The endgame of cytokinesis can follow one of two pathways depending on developmental context: resolution into separate cells or formation of a stable intercellular bridge. Here we show that the four wheel drive (fwd) gene of Drosophila melanogaster is required for intercellular bridge formation during cytokinesis in male meiosis. In fwd mutant males, contractile rings form and constrict in dividing spermatocytes, but cleavage furrows are unstable and daughter cells fuse together, producing multinucleate spermatids. fwd is shown to encode a phosphatidylinositol 4-kinase (PI 4-kinase), a member of a family of proteins that perform the first step in the synthesis of the key regulatory membrane phospholipid PIP2. Wild-type activity of the fwd PI 4-kinase is required for tyrosine phosphorylation in the cleavage furrow and for normal organization of actin filaments in the constricting contractile ring. Our results suggest a critical role for PI 4-kinases and phosphatidylinositol derivatives during the final stages of cytokinesis.


Subject(s)
1-Phosphatidylinositol 4-Kinase/metabolism , Actins/metabolism , Drosophila melanogaster/enzymology , Spermatozoa/cytology , 1-Phosphatidylinositol 4-Kinase/chemistry , 1-Phosphatidylinositol 4-Kinase/genetics , 1-Phosphatidylinositol 4-Kinase/physiology , Amino Acid Sequence , Animals , Base Sequence , Cell Division , Cleavage Stage, Ovum/physiology , DNA, Complementary , Drosophila melanogaster/embryology , Humans , Male , Meiosis/physiology , Molecular Sequence Data , Phosphorylation , Protein Structure, Tertiary , Sequence Homology, Amino Acid , Spermatozoa/metabolism , Spermatozoa/physiology , Tyrosine/metabolism
20.
J Appl Clin Med Phys ; 1(2): 76-85, 2000.
Article in English | MEDLINE | ID: mdl-11674821

ABSTRACT

Radiation oncology is a highly complex medical specialty, involving many varied routine and special procedures. To assure cost-effectiveness and maintain support for the medical physics program, managers are obligated to analyze and defend all aspects of an institutional billing and cost-reporting program. Present standards of practice require that each patient's radiation treatments be customized to fit his/her particular condition. Since the use of personnel time and other resources is highly variable among patients, graduated levels of charges have been established to allow for more precise billing. Some radiation oncology special procedures have no specific code descriptors; so existing codes are modified or additional information attached in order to avoid payment denial. Recent publications have explored the manpower needs, salaries, and other resources required to perform radiation oncology "physics" procedures. This information is used to construct a model cost-based resource use profile for a radiation oncology center. This profile can be used to help the financial officer prepare a cost report for the institution. Both civil and criminal penalties for Medicare fraud and abuse (intentional or unintentional) are included in the False Claims Act and other statutes. Compliance guidelines require managers to train all personnel in correct billing procedures and to review continually billing performance.


Subject(s)
Financial Management/methods , Radiation Oncology/economics , Costs and Cost Analysis/methods , Equipment and Supplies, Hospital/economics , Forms and Records Control , Hospital Costs/statistics & numerical data , Humans , Physical Phenomena , Physics , Radiation Oncology/instrumentation , Workforce
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