cssi/SciSciGPT-SciSciNet huggingface dataset:
Comparative Urban Drive Cycle Simulations of Light-Duty Hybrid Vehicles with Gasoline or Diesel Engines and Emissions Controls

Electric hybridization is a very effective approach for reducing fuel consumption in light-duty vehicles. Lean combustion engines (including diesels) have also been shown to be significantly more fuel efficient than stoichiometric gasoline engines. Ideally, the combination of these two technologies would result in even more fuel efficient vehicles. However, one major barrier to achieving this goal is the implementation of lean-exhaust aftertreatment that can meet increasingly stringent emissions regulations without heavily penalizing fuel efficiency. We summarize results from comparative simulations of hybrid electric vehicles with either stoichiometric gasoline or diesel engines that include state-of-the-art aftertreatment emissions controls for both stoichiometric and lean exhaust. Fuel consumption and emissions for comparable gasoline and diesel light-duty hybrid electric vehicles were compared over a standard urban drive cycle and potential benefits for utilizing diesel hybrids were identified. Technical barriers and opportunities for improving the efficiency of diesel hybrids were identified.
Primate models for australopithecine sexual dimorphism

Several different models of sexual dimorphism in the South African australopithecines are compared with sexual dimorphism in the living primates. Australopithecine dimorphism is placed in an evolutionary context, and contrasting trends in the hominid and pongid lineages are shown. Evidence suggesting that the australopithecines were an extremely polytypic taxon is presented, and a high level of both inter- and intra-population variation is indicated.
Learner Characteristics and Performance Effects in Self-Paced Instruction for Community College Students

No differences in performance were found among a control and two treatment groups, but some interesting attitudinal differences emerged.
Probabilistic models as theories of children's minds

My research program proposes that children have representations and learning mechanisms that can be characterized as causal models of the world – coherent, structured hypotheses with consistent relationships to probabilistic patterns of evidence. We also propose that Bayesian inference is one mechanism by which children learn these models from data. These proposals are straightforward psychological hypotheses and far from “Bayesian Fundamentalism.”
Managing heartburn at the 'base' of the GERD 'iceberg': effervescent ranitidine 150 mg b.d. provides faster and better heartburn relief than antacids.

Background: Many individuals with heartburn self-medicate with antacids for relief of their symptoms. Aim: To compare efficacy of effervescent ranitidine to as-needed calcium carbonate antacids in subjects who self-treat heartburn. Methods: A total of 155 subjects with frequent antacid-responsive heartburn were randomized to receive effervescent ranitidine 150 mg tablets b.d., or as-needed calcium carbonate 750 mg for 12 weeks. Endoscopic oesophagitis severity and mucosal histology were assessed at baseline, and at weeks 6 and 12. Heartburn frequency, severity, and antacid consumption were recorded daily, and quality of life was assessed at baseline, and at weeks 6 and 12. Results: Heartburn frequency and severity were significantly decreased after 1 day of ranitidine (P < 0.02). By week 6, ranitidine had significantly decreased rescue antacid consumption (7.3 tablets, P < 0.001) vs. antacids (14.1 tablets). Endoscopic oesophagitis healing (≤ grade 1) was significantly better with ranitidine (55%, P=0.022) vs. antacids (29%). Quality of life was improved by both treatments; however, ranitidine was numerically superior for all quality of life parameters, statistically superior for several quality of life indices at week 6 and for the pain-related index by week 12 (P < 0.05). Conclusions: For subjects self-administering antacids for chronic heartburn, effervescent ranitidine 150 mg b.d. is more effective than antacids in reducing heartburn, healing erosive oesophagitis, alleviating pain, and improving quality of life.
A model of pedestrian-induced bridge vibration based on full-scale measurement

Abstract It is now well-known that, under pedestrian excitation, flexible footbridges can exhibit large-amplitude vibrations that impact their serviceability. In particular, some footbridges of suspended spans have exhibited significant lateral oscillation due to pedestrian–bridge interaction. This paper presents the characteristics of pedestrian-induced vibration of a prestressed concrete beam bridge observed using full-scale measurement. The effect of the pedestrian loading on the oscillation frequency of the bridge, as well as its implication on the mechanism of pedestrian–bridge interaction, is investigated. Based on the understanding of the prototype vibration, a model is developed to enable assessment of the amplitude of footbridge vibration induced by pedestrian excitation.
Timing of Intravenous Immunoglobulin Treatment and Risk of Coronary Artery Abnormalities in Children with Kawasaki Disease

Background Kawasaki disease (KD) is a type of febrile self-limiting systemic vasculitis, which affects the coronary arteries (CA) and may cause cardiac ischemia during childhood and adult life. Intravenous immunoglobulin (IVIG) has become the standard therapy for KD. However, it is still uncertain if CA outcome is associated with the timing of IVIG administration with reference to fever onset. Methods The present study was designed to identify the risk for development and delay in resolution of CA abnormalities in association with IVIG administration within or after 10 days of KD onset. A retrospective analysis of clinical signs, laboratory data, and prospectively collected echocardiography (ECHO) results of 106 children hospitalized with KD was utilized. Results IVIG was administered to 86 (81.1%) patients within 10 days, and 20 (18.9%) patients received the first dose of IVIG after 10 days of illness. Among 23 (21.6%) patients who were diagnosed with CA lesions, 18 had a CA abnormality at initial ECHO, whereas they appeared after IVIG therapy in five patients. The risk for CA lesions on initial ECHO was higher among the patients who were admitted after 10 days of disease onset [odds ratio (OR) = 5.3, 95% confidence interval (CI) = 1.7–15.9] but comparable with the post-IVIG treatment group (OR = 3.1, 95% CI = 0.48–19.8). The age 40 mm/hour were associated with non-resolution of CA lesions within 9 weeks of KD onset. Overall, 95.6% of children had resolution of CA abnormalities within 6 months of onset of KD symptoms. Conclusion The results of this study suggest that although IVIG treatment within 10 days is important to minimize development of cardiac pathology, neither occurrence of CA lesions in IVIG-treated children nor the time frame for resolution of established CA abnormalities was associated with the timing of IVIG administration. Age 40 mm/hour) predict a delay in resolution of CA lesions among children with KD.
Can simulation improve the traditional method of root cause analysis: A preliminary investigation

Introduction The Joint Commission on Accreditation of Healthcare Organizations recommendations for conducting root cause analysis (RCA) include identifying “root causes” and “common-cause variation” rather than “proximate causes” and “special-cause variation” to create interventions. Simulation for health care RCA is a novel technique but has not been compared with traditional RCA methods. Methods All of the RCAs of adverse events conducted at Tulane Hospital between September 2010 and September 2011 were reviewed. A case of missed postprocedural, preoperative hemorrhage resulting in death was chosen. Hospital records were analyzed to identify the presumed root causes. A simulation of the event was developed and conducted. Six test subjects (preoperative and postanesthesia care unit nurses) participated in the simulation. Root causes identified by simulation analysis were compared with those identified by traditional RCA. Results In 2 of 6 simulations, the adverse event was duplicated. The root cause identified by standard RCA technique was inattention to signs of bleeding in the patient/ lack of appropriate monitoring of the patient by nursing staff (“special-cause variation”). Simulation-based RCA revealed that the root cause was not only inadequate monitoring, but also the lack of physical presence of physicians in the care environment (“common-cause variation”). Simulation-based RCA identified root causes more amenable to intervention. Discussion This study demonstrates that simulation-based RCA can identify additional root causes amenable to making health care interventions when compared with traditional RCA.
Electrocardiogram simulation using a personal computer

A personal computer with a digital-to-analog converter is used as an electrocardiogram simulator. A TurboPascal procedure, given the heart rate, rhythm, and ST segment levels, generates the voltages for Leads II and V5. A simple circuit reduces the voltages to the physiologic range and smoothes the waveforms, removing the staircase effects of digitalization. The procedure can be manually controlled using a software interface or driven by other programs for use in a full-scale operating room simulator.
Experimental and numerical investigation of an 8-cm valveless pulsejet

Abstract This paper investigates the performance of a small scale pulsejet whose overall length is approximately 8 cm, the smallest pulsejet ever reported to the author’s knowledge. Gas dynamics, acoustics and chemical kinetics were modeled to gain an understanding of various physical phenomena affecting pulsejet operation, scalability, and efficiency. Numerical simulations were performed utilizing CFX to model 3-D compressible vicious flow in the pulsejet using the integrated Westbrook–Dryer single step combustion model. The simulation results were validated with experimental data and provide physical insight into the pulsejet operation. The pulsejet was run in valveless mode on hydrogen fuel with either a forward-facing inlet or a pair of rearward-facing inlets. Pressure, temperature, thrust, and frequency were measured as a function of valveless inlet and exit lengths and different geometries. As expected, the rearward-facing inlet produced considerably more net thrust, although still not very efficient, with a TSFC of 0.02 kg/N-h. The operating frequency was found to scale with inlet length to the negative 0.22 power, in addition to the inverse of the overall length for valved pulsejet.
Identification and characterization of a novel enhancer for the human MCT‐1 oncogene promoter

Cloning and characterization of the promoter region for the MCT-1 oncogene is described. We used luciferase assays to identify cis-acting elements responsible for human MCT-1 promoter function. The MCT-1 promoter is TATA-less with a consensus initiator element located at the transcription start site and facilitated by two Sp1 sites that directs basal transcription. Deletion of a region of the MCT-1 promoter (-133 to -122) resulted in significant decrease in luciferase activity, suggesting that this region contains a positive cis-acting element. Using mobility shift assays with a 26-mer oligonucleotide, which contains this fragment and its flanking regions, we demonstrated the presence of sequence-specific DNA-binding protein in both Jurkat and Hela nuclear extracts that we designated as LMBF (for lymphoid MCT-1 binding factor). This 26-mer oligonucleotide containing the LMBF binding site is required for maximum transcriptional activity of the MCT-1 promoter. Although the 26-mer oligonucleotide contains a sequence with strong homology to a heat-shock factor consensus, competitive electrophoretic mobility shift assay (EMSA) analysis demonstrated that the binding protein is not a known member of heat shock family. Furthermore, this sequence when placed in reverse orientation downstream of the luciferase gene was able to enhance luciferase activity driven by a minimal promoter. These data are consistent with this sequence behaving as an enhancer. Finally, Southwestern blot analysis revealed a 96-kDa protein capable of binding a probe containing the LMBF binding site.
On the Other Hand: Current Issues in and Meta-Analysis of the Behavioral Laterality of Hand Function in Nonhuman Primates

The last decade has seen a resurgence of interest in laterality of function in primates, especially in hand use as it links to handedness and language in Homo sapiens. Manual lateralization of behavior in humans reflects asymmetry in cerebral structure, which must have evolved from nonhuman progenitors. To what extent is hand function lateralized in our nearest living relations? First, we address current issues of theory and methodology: statistics, measurement, variables, setting, sensory modality, and sample size. Specific topics include preference vs. performance, posture, bimanuality, inheritance, and arm asymmetry. We categorize the published literature in a descriptive, classificatory framework of five levels that range from Level 1, ambilaterality, to Level 5, human-like handedness. In a meta-analysis we put 241 published data-sets to a methodological test of seven criteria and code the 48 survivors onto the levels framework, by taxonomic grouping (prosimian, New World monkey, Old World monkey, ape, chimpanzee). Primates at Level 1 are mostly wild or naturalistic populations performing spontaneous species-typical behavior patterns. Most primates are at Levels 2 and 3, that is, individually lateralized to either side, especially on complex, demanding or practiced tasks, usually as devised in captive settings. Only chimpanzees show signs of population-level bias (Levels 4 and 5) to the right, but only in captivity and only incompletely. We conclude that nonhu- man primate hand function has not been shown to be lateralized at the species level—it is not the norm for any species, task, or setting, and so offers no easy model for the evolution of human handedness. Yrbk Phys Anthropol 40:201- 232, 1997. r 1997 Wiley-Liss, Inc.
School-based tobacco use prevention.

Abstract Although school-based tobacco use prevention programs have had limited short-term success, questions remain about whether these programs would have the same degree of success with youths at risk for habitual tobacco use. This article describes a pilot project to discriminate these high-risk youths low-risk youths. Two hundred twenty-five consenting youths from a western state completed a questionnaire containing individual, demographic, and environmental correlates of habitual tobacco use. The total sample consisted of 105 males and 119 females. Nineteen percent came from ethnic minorities, and 69% were from traditional households. Discriminant function analyses identified correlates that discriminated between current tobacco users and non-users as well as students intending to use tobacco from those who did not.
The Effects of Concurrent Cognitive Load on Phonological Processing in Adults Who Stutter

Purpose To determine whether phonological processing in adults who stutter (AWS) is disrupted by increased amounts of cognitive load in a concurrent attention-demanding task. Method Nine AWS and 9 ...
Rheological study of concentrated silica suspensions

Abstract Concentrated silica-water suspensions were studied using a rotational viscometer to obtain rheological data and a Zeta-meter to determine the electrophoretic mobility. The viscometric data were analyzed as functions of shear rate, solids concentration and electrophoretic mobility. The dependence of electrophoretic mobility on pH was also studied. The Bingham plastic model and the power law model were applied to the data and the power law model described the data more closely. The parameters for the two models were correlated to solids concentration and electrophoretic mobility. The effect of particle size on apparent viscosity was also investigated. A conceptual model was proposed for the dependence of electrophoretic mobility on pH.
North Carolina continental slope zoogeographical barrier

Abstract Collections of sipunculans and pogonophorans from depths between 150 and 2000 m around latitude 35°30′N were analyzed and used to supplement earlier information from this region. The addition of eight pogonophoran species from this area and minor revisions of earlier data reaffirm and strengthen the hypothesis that a zoogeographical barrier for slope dwelling infauna exists around 34°N off Cape Lookout, North Carolina.
Plate finite element modeling of laminated plates

Abstract A plane finite element is developed based on a lamination theory which includes the effect of transverse shear deformation. In modeling 2-D delaminations in laminated plates, the undelaminated region is modeled by a single layer of plate elements while the delaminated region is modeled by two layers of plate elements whose interface contains the delamination. To ensure the compatibility of deformation and equilibrium of resultant forces and moments at the delamination crack tip, a multipoint constraint algorithm has been developed and incorporated into the finite element code. In addition, the virtual crack closure technique has been modified and implemented into the code so that the strain energy release rate could be computed using the plate elements.
Mechanistic, Functional and Immunopharmacological Implications of Biochemical Studies of Antigen Receptor-Triggered Cytolytic T-Lymphocyte Activation*

Biochemical events that follow the engagement of cytotoxic T lymphocytes (CTL) with an Ag-bearing target cell (TC) or triggering by the crosslinking of the Ag-receptor (TcR) by immobilized anti-TcR mAb were studied using cloned CTL and a novel CTL activation assay. The approach described here was undertaken to shed light on the molecular mechanisms of "ON", "STOP" and "OFF" signalling that allow CTL to be activated, kill TC and disengage from the target cell after delivery of the "lethal hit" and then to proceed with the destruction of the next Ag-bearing target encountered. Biochemical studies of TcR-regulated and TcR-triggered constitutive exocytosis in CTL provided a detailed description of the molecular requirements for this important phenomenon in T lymphocytes and provided an alternative CTL activation assay; this assay measures the TcR-dependent response in the absence of a TC. These studies also helped to envision CTLs screening activities as a cycle of engagements-disengagements with the TC, where every surrounding cell is treated by the CTL as a potential Ag-bearing TC. Both constitutive and regulated exocytosis in CTL are triggered through a transmembrane signalling pathway which involves protein kinase C and extracellular Ca2+ that, most likely, is translocated through Ca2+ channels. This is followed by the involvement of calmodulin (CaM)-binding proteins, e.g., calcineurin, a CaM-dependent phosphatase, which was shown to be a major CaM-binding protein in murine lymphocytes. Unexpectedly, these biochemical studies demonstrated that the granule exocytosis model of CTL-mediated cytotoxicity cannot account for the mechanism of target cell lysis by CTL, at least in in vitro conditions in the absence of extracellular Ca2+. These results indicate the existence of an extracellular Ca2+-independent, TcR-regulated CTL response and raise the possibility that second messenger(s) other than Ca2+ and/or products of phosphoinositide turnover are involved in T-cell lysis. Predominance of "non-lethal" engagements between some CTL and TC, revealed during time-lapse cinematographic studies, together with comparative studies of TcR-regulated exocytosis of granules and of constitutive exocytosis of gamma-interferon, suggested that TC destruction by CTL may not be their only or even their most important function in vivo. It is possible that CTL, triggered by Ag recognition to exocytose storage granules and to synthesize and constitutively exocytose macrophage-activating factors, in turn promote tumor destruction by macrophages.(ABSTRACT TRUNCATED AT 400 WORDS)
Fatty Acid Trafficking in Starved Cells: Regulation by Lipid Droplet Lipolysis, Autophagy, and Mitochondrial Fusion Dynamics

Fatty acids (FAs) provide cellular energy under starvation, yet how they mobilize and move into mitochondria in starved cells, driving oxidative respiration, is unclear. Here, we clarify this process by visualizing FA trafficking with a fluorescent FA probe. The labeled FA accumulated in lipid droplets (LDs) in well-fed cells but moved from LDs into mitochondria when cells were starved. Autophagy in starved cells replenished LDs with FAs, increasing LD number over time. Cytoplasmic lipases removed FAs from LDs, enabling their transfer into mitochondria. This required mitochondria to be highly fused and localized near LDs. When mitochondrial fusion was prevented in starved cells, FAs neither homogeneously distributed within mitochondria nor became efficiently metabolized. Instead, FAs reassociated with LDs and fluxed into neighboring cells. Thus, FAs engage in complex trafficking itineraries regulated by cytoplasmic lipases, autophagy, and mitochondrial fusion dynamics, ensuring maximum oxidative metabolism and avoidance of FA toxicity in starved cells.
Impact of Sugar Pucker on Base Pair and Mispair Stability

The selection of nucleoside triphosphates by a polymerase is controlled by several energetic and structural features, including base pairing geometry as well as sugar structure and conformation. Whereas base pairing has been considered exhaustively, substantially less is known about the role of sugar modifications for both nucleotide incorporation and primer extension. In this study, we synthesized oligonucleotides containing 2'-fluoro-modified nucleosides with constrained sugar pucker in an internucleotide position and, for the first time, at a primer 3'-end. The thermodynamic stability of these duplexes was examined. The nucleoside 2'-deoxy-2'-fluoroarabinofuranosyluracil [U(2'F(ara))] favors the 2'-endo conformation (DNA-like), while 2'-deoxy-2'-fluororibofuranosyluracil [U(2'F(ribo))] favors the 3'-endo conformation (RNA-like). Oligonucleotides containing U(2'F(ara)) have slightly higher melting temperatures (T(m)) than those containing U(2'F(ribo)) when located in internucleotide positions or at the 3'-end and when correctly paired with adenine or mispaired with guanine. However, both modifications decrease the magnitude of DeltaH degrees and DeltaS degrees for duplex formation in all sequence contexts. In examining the thermodynamic properties for this set of oligonucleotides, we find entropy-enthalpy compensation is apparent. Our thermodynamic findings led to a series of experiments with DNA ligase that reveal, contrary to expectation based upon observed T(m) values, that the duplex containing the U(2'F(ribo)) analogue is more easily ligated. The 2'-fluoro-2'-deoxynucleosides examined here are valuable probes of the impact of sugar constraint and are also members of an important class of antitumor and antiviral agents. The data reported here may facilitate an understanding of the biological properties of these agents, as well as the contribution of sugar conformation to replication fidelity.
Relationship of Use of Dairy Herd Improvement Records to Herd Performance Measures

Abstract Questionnaires and DHI herd summaries from 543 Ohio dairy farmers with Holstein cows were analyzed in relation to changes in herd performance measures, milk production, and herd size from 1976 to 1983. Milk production per cow increased 77.3 kg/yr and herd size increased by 11.8 cows during the period. Percent cows culled increased, but age at first and last calvings decreased significantly. Calving interval, days to first service, age at first calving, and age at last calving were significant contributors to change in milk production from 1976 to 1983. Respondents who agreed strongly that DHI records were worth the price increased production per cow by 816 kg from 1976 to 1983 compared with 254 and 63 kg for respondents who where neutral or strongly disagreed with the question. Percent changes in herd size and production were highest for younger farmers. Respondents with more productive herds thought they had adequate time to analyze their records.
The in vitro degradation of dihydrosphingosine.

Abstract A cell-free system has been obtained in rat liver which catalyzes the formation of palmitic acid from dihydrosphingosine. The enzymatic activity appears to be localized mainly in the mitochondrial fraction and is quite labile. The breakdown of dihydrosphingosine has been found to require ATP and Mg2+. Dialyzed or washed enzyme preparations are stimulated by the addition of pyridoxal phosphate and enzymatic activity is lost when incubation takes place in the presence of pyridoxalenzyme inhibitors such as semicarbazide or bisulfite. These facts are consistent with the proposal that the cleavage of dihydrosphingosine is carried out by a pyridoxalenzyme. Other data indicate that the reaction may proceed in a manner analogous to the cleavage of threonine by threonine aldolase and that palmitaldehyde may be an intermediate in the reaction.
We're crippling our kids with kindness!!

Abstract Quite often as teachers we try to help our students by giving them short cuts or help with strategies they don't understand. We tend to ignore the need that children have to struggle with a problem before proper referents can be established. This article explores that need from results obtained while working with two classes of students: one class was made up of second graders and the other class were third graders. The problem was observed while working with the students on a project designed to established the proper concept of equality in the minds of the students and to help them develop some strategies for solving missing number problems. The results were suprising and startling and led to the realization that we, as teachers, are often too kind to our students for their own best good. We actually cripple our students mentally by feeding them too many hints and by trying to push them algorithmically beyond their ability without the development of proper referents for the mathematics being taught. It, too often, leads to rote memorization and prevents the students' development of a proper conceptual understanding. Concrete referents are essential before the establishment of a conceptual background can be firmly developed in the minds of each student.
Effects of transmission gear selection on tractor performance and fuel costs during deep tillage operations

Abstract Deep tillage operations required to alleviate soil compaction common in the Southeastern US remain energy intensive and expensive. Equipment performance and in-field efficiency are two variables that can be improved to minimize fuel consumption and ultimately reduce input costs for crop production. The objective of this study was to investigate the effects of transmission gear selection on fuel costs, draft, and other equipment performance variables using two deep tillage implements. Three different transmission gears were selected which represented slow, normal, and fast operating speeds for two typical in-row, integral subsoilers (KMC generation I rip-strip and Bigham Brothers Paratill™). Tractor fuel consumption, slip, axle torque, and engine speed were measured in real-time along with transverse and vertical draft forces. Results indicated a 105% increase in fuel consumption rate, a 28% increase in implement draft, and a 255% increase in power between the slow and fast speed for the Paratill™. The KMC showed a 115% increase in fuel consumption rate, a 37% increase in implement draft, and a 283% increase in power between the slow and fast speeds. Good comparisons were found between measured and estimated, using published equations, for fuel consumption (−5.3% to 4.9%) and draft (−3.6% to 17.7%). For the Paratill™, the normal speed produced the lowest fuel cost ($ 5.10/ha) but operating at this speed reduced productivity rate from 4.55 ha/h at the fast speed down to 3.23 ha/h. Conversely, the KMC fast speed provided the lowest fuel cost ($ 5.35/ha) and highest productivity rate (4.35 ha/h) for this implement. In general, the Paratill™ provided the highest productivity and lowest fuel cost when operated at the typical speeds in the Southeastern US (around the normal to fast) mostly likely due to the lower required draft. In summary, the minimum fuel usage for each implement occurred at a different ground speed however, productivity was maximized at the fast speed with data reported useful to practitioners managing these style tillage implements.
Analytical scheduling of small nursing teams

Abstract By using empirical studies of nursing organizations and theoretical models, improvements in- the utilization of nursing teams have been achieved. These improvements are evidenced by increased time spent with the patient rather than on other duties. A problem, so far unresolved, arises with the need to change the allocation of nurses to patients at certain times. Whilst this did not hinder the operation of the scheme when it was tested, nurses expressed some reservations on this point, and further research is clearly required.
Comparison of MR imaging after barium administration with CT in pelvic disease.

The use of magnetic resonance (MR) imaging for evaluating the abdomen and pelvis has been limited by the lack of a suitable contrast agent. The purpose of this study was to compare axial MR imaging after rectal barium administration with computed tomography (CT) for delineation of normal anatomy and lesions of the pelvis. MR images and CT scans of 11 patients were studied retrospectively and independently by four radiologists. No substantial differ-ences in the visualization of normal bowel, iliac vessels, lymph nodes, bladder, prostate, seminal vesicles, uterus, and cervix and in detection of abnormalities were seen between CT scans and axial MR images obtained after barium administration. This preliminary study suggests that axial MR imaging with rectal barium is a useful alternative to CT in evaluating pelvic disease.
The effect of laparoscopic cholecystectomy on resident training

background : The purpose of this study was to determine the impact of laparoscopic cholecystectomy (LC) on resident training. materials and methods : We reviewed our experience over an 11-year period, from academic years 1982 to 1992, with 3,046 patients who underwent elective open cholecystectomy (OC) and 640 patients who underwent LC. results : Prior to LC, junior residents performed 80% of all cholecystectomies, with a morbidity and mortality rate of 4% and 0.04%, respectively, compared with 11% and 0.3%, respectively, for senior residents who operated on higher-risk patients. Since the introduction of the technique, there has been a 25% increase in cholecystectomies per year, and a reduction in junior resident OC experience by 67%. Currently, 72% of all cholecystectomies are performed laparoscopically by senior residents. conclusion : The replacement of OC by LC has produced a qualitative change in the operative experience of our junior residents and a delay in acquisition of operative skills. The reduction in OC experience by residents may jeopardize their ability to perform the difficult open cases.
Ising Critical Exponents in Real Fluids: An Experiment

We report precise optical measurements of the equations of state of Xe, S${\mathrm{F}}_{6}$, and C${\mathrm{O}}_{2}$ very near their critical points ($\frac{|T\ensuremath{-}{T}_{c}|}{{T}_{c}}l5\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}5}$). We find that the critical exponents of these fluids in this region are close to the exponents calculated from the three-dimensional Ising model.
Quantitation of phosphate metabolites in human leg in vivo.

Slice-selective 31P MR spectra were recorded from human legs with a pulse program which has only a 1.5-ms delay between excitation and acquisition. The volume of the slice was calculated from its thickness and cross-sectional area measured with the aid of a computer program. A phosphate reference standard spectrum was recorded from the Same interplanar location as that of the human leg slice. Since signal integral is proportional to the phosphate concentration and to the volume of the slice, metabolite concentrations in the selected slice could be quantitated. © 1988 Academic Press, Inc.
Organosilane insecticides. Part II: Chemistry and structure—activity relationships

Silicon effectively substitutes for quaternary carbon in etofenpr ox-type insecticides; the resulting dimethyl-4-ethoxyphenyl-3-(4-fluoro-3-phenoxyphenyl)propylsilane is a broad-spectrum insecticide with extremely low toxicity to fish. Four regions of this new silane insecticide have been systematically altered. The methyl groups on silicon appear to be critical for activity. Replacement of the fluorine with hydrogen results in a substantial loss of activity. The aromatic rings of the phenoxyphenyl fragment are best tethered by oxygen or carbonyl, the methylene and nitrogen analogs being of very low toxicity to the test species. The activity ranking of the methylene and carbonyl tethers is opposite to that found for ester pyrethroids. The relationship of insecticidal activity to the aromatic substituent para to the silicon atom has been found to correlate with the molar refractivity of the substituent. Replacement of a tetra-substituted carbon atom with a silicon atom can simplify construction of test compounds and thus be advantageously used in the exploration of structure—activity relationships. A novel method for preparing allylbenzenes from aromatic aldehydes was also developed.
Distributed Phase Correction Technique

We broadly use the term phase alignment to encompass the repositioning of edges in one signal with respect to edges in another ``reference'' signal. This paper introduces a phase alignment block, and exemplifies its operation in a couple of separate contexts. A recurring theme in these contexts is the use of phase alignment via temporal- and spatial-mixing/multiplexing. We term both forms of mixing as performing ``distributed'' phase correction. The distinguishing feature in these contexts is the employment of the phase alignment block to either enhance or add additional functionality to conventional timing blocks. In the context of a voltage controlled delay line for a delay locked loop (DLL), we examine how the distributed mixing reduces both jitter and duty cycle disturbances. And in the context of a phase error detector and correction block for a phase locked loop (PLL), we examine how distributed coupling adds a design dimension in terms of trading off phase correction gain versus cycle jitter.
The Rationale for a Temporary Speech Prosthesis in Palatal Insufficiency

For the speech clinician who is experienced in the evaluation of children with repaired cleft palate it is not difficult to determine that a child's palate is inappropriate in movement and/or length for adequate voice and articulation development. A child evaluated at two, two-and-a-half, and three years of age will generally have given enough speech clues for the clinician to make such a judgement. No x-ray studies need be required to make this determination, only the trained ear of the clinician and his observations.
Determination of carotenoid as the purple pigment in Gorgonia ventalina sclerites using Raman microscopy

The production of purple pigment in gorgonian sclerites in response to biotic insults has been used to determine the disease state of these organisms. The chemical nature of the pigment present in the sclerites has until now been unknown. Using Raman microscopy, it was determined that this pigment is a carotenoid with a polyene chain containing between 14 and 15 carbon double bonds.
Alterations in cation levels and Na-K ATPase activity in rat cerebral cortex during the development of cobalt-induced epilepsy

— This study was carried out to ascertain what biochemical changes might be present in cobalt-induced epilepsy in the rat. Sodium, potassium, calcium, magnesium, Na-K ATPase activity, water content, protein content and the ability of the tissue to utilize oxygen were measured in (1) the area of the cerebral cortex in which the cobalt was implanted; (2) in an area adjacent to but not including the area of the lesion; and (3) in the homotopic area of the contralateral cerebral cortex. The greatest changes were observed in the area of the lesion itself, with marked increases in calcium, magnesium and sodium contents and decreases in potassium content, Na-K ATPase activity, protein content and the ability of the tissue to utilize oxygen. The only significant findings in the area adjacent to the lesion and in the contralateral cortex were a modest elevation of sodium and a modest decrease in potassium at different time periods after implantation of the cobalt. We feel that the changes observed at the site of cobalt implantation may reflect tissue destruction which is unrelated to the epileptic process.
Spectroscopic Properties and Potential Energy Curves for 21 Electronic States of CrH

Abstract Spectroscopic constants and potential energy curves of 21 electronic states of CrH are obtained using the all-electron complete active space multiconfiguration self-consistent field (CASMCSCF) followed by first-order configuration interaction (FOCI) and full second-order CI (SOCI) and multireference CI including Rydberg states calculations. The ground state of CrH is found to be of 6 Σ + symmetry with r e = 1.690 A, ω e = 1592 cm −1 , D e = 2.11 eV, and μ e = 3.864 D at the SOCI level. Several optical transitions for CrH are predicted. Our computations support the reassignment of the state perturbing the A-X system to 4 Σ + suggested by Ram et al. Our computed spectroscopic constants for the A , X , and a 4 Σ + state are in excellent agreement with the experimental values reported by Ram et al.
Cation intersite distributions in iron-bearing minerals via electrical conductivity/seebeck effect

The equilibrium high temperature cation intersite distributions in iron-bearing minerals which exhibit small polaron “hopping” conduction can be determined by a technique which combines electrical conductivity and Seebeck effect. The procedure is demonstrated for ferrospinels (Fe3O4) - FeAl2O4 and Fe3O4 - CoFe2O4) and applied to the olivine Fe2SiO4 - Mg2SiO4 system.
Effects of phonological similarity on priming in auditory lexical decision.

Two auditory lexical decision experiments were conducted to determine whether facilitation can be obtained when a prime and a target share word-initial phonological information. Subjects responded “word” or “nonword” to monosyllabic words and nonwords controlled for frequency. Each target was preceded by the presentation of either a word or nonword prime that was identical to the target or shared three, two, or one phonemes from the beginning. The results showed that lexical decision times decreased when the prime and target were identical for both word and nonword targets. However, no facilitation was observed when the prime and target shared three, two, or one initial phonemes, These results were found when the interstimulus interval between the prime and target was 500 msec or 50 msec. In a second experiment, no differences were found between primes and targets that shared three, one, or zero phonemes, although facilitation was observed for identical prime-target pairs. The results are compared to recent findings obtained using a perceptual identification paradigm. Taken together, the findings suggest several important differences in the way lexical decision and perceptual identification tasks tap into the information-processing system during auditory word recognition.
The right to know.

The following is the Gehrmann Memorial Lecture, presented October 16, 1975 at the annual meeting of the American Academyof Occupational Medicine, in Houston, Texas. Professor Harold J. Magnuson discusses the social changes that have developed over the last twenty years in association with advances in the fields of environmental and occupational health. In particular, Dr. Magnuson focuses on the problems of evaluating and distributing the information generated by scientific research in these fields. Consumerism, public mistrust of institutions, bureaucracy, governmental policy making, and the limitations of expertise are examined in their relation to this theme.
Markets, pooling and insurance for managing bycatch in fisheries

Abstract Bycatch is a nearly universal problem for fisheries, and it is increasingly common to place strict limits on allowable bycatch either on individuals or an industry sector. Individual bycatch quotas strengthen individual incentives to avoid bycatch and may reduce the likelihood that the bycatch cap will limit target species catch. However, in cases where bycatch is highly uncertain and variable, individual quotas and markets may be subject to high price variability and may fail to allocate quota efficiently. In some cases such as sea turtles, marine mammals, rare seabird and certain fish species, the allowable take may be less than one per permit holder. There are a number of reasons to believe that a transferable quota market may not function effectively in these cases. I explore the implications of stochasticity and uncertainty of bycatch for valuing quota in an individual bycatch quota system. I explore the degree to which a quota market increases expected profit and reduces individual risk relative to simply having a non-transferable individual bycatch quota, and how pooling approaches and possibly market insurance can be used to reduce financial risk for fishermen associated with uncertain bycatch.
EFFECTS OF SOCIAL CONTEXT, REINFORCER PROBABILITY, AND REINFORCER MAGNITUDE ON HUMANS' CHOICES TO COMPETE OR NOT TO COMPETE

In the first two experiments, subjects' choices to earn points (exchangeable for money) either by competing with a fictitious opponent or by not competing were studied. Buskist, Barry, Morgan, and Rossi's (1984) competitive fixed-interval schedule was modified to include a second response option, a noncompetitive fixed-interval schedule. After choosing to enter either option, the opportunity for reinforcers became available after the fixed-interval's duration had elapsed. Under the no-competition condition, points were always available after the interval had elapsed. Under the competition condition, points were available based on a predetermined probability of delivery. Experiments 1 and 2 examined how reinforcer probabilities and reinforcer magnitudes affected subjects' choices to compete. Several general conclusions can be made about the results: (a) Strong preferences to compete were observed at high and moderate reinforcer probabilities; (b) competing was observed even at very low reinforcer probabilities; (c) response rates were always higher in the competition component than in the no-competition component; and (d) response rates and choices to compete were insensitive to reinforcer-magnitude manipulations. In Experiment 3, the social context of this choice schedule was removed to determine whether the high levels of competing observed in the first two experiments were due to a response preference engendered by the social context provided by the experimenters through instructions. In contrast to the first two experiments, these subjects preferred the 60-s fixed-interval schedule (formerly the no-competition option), indicating that the instructions themselves were responsible for the preference to compete. This choice paradigm may be useful to future researchers interested in the effects of other independent variables (e.g., drugs, social context, instructions) on competitive behavior.
A Hearty Welcome to the Oldest New Kid on the Block: Epidemiology

To prevent misunderstanding, I begin at the end: the point of this Editorial is to celebrate and welcome Editor Barbara Gilchrest’s decision to elevate epidemiology to one of the (now) 12 permanent discipline-based sections in the Journal. This decision is certainly overdue; it should have been made by the previous Editor-in-Chief, but I am quite pleased to see it happen now. In fact, Tamar Nijsten (the new section editor, a wise choice) and Rob Stern have made my assignment easier through their comprehensive review of cutaneous epidemiology published in the 75th-anniversary special edition of the Journal (Nijsten and Stern, 2012). Sufficient reasoning can be found in that review, although my reasoning follows the following, somewhat different, track.
Proposal of broadband optical delay with fine delay resolution utilizing high-confinement silicon waveguides

This proposal for an optical delay element, with a broad operation bandwidth and fine delay resolution, highlights the compact and nonresonant circuit design, as well as the size reduction of wavelength-insensitive couplers utilizing silicon waveguides.
Near-infrared image-guided laser ablation of dental decay.

Image-guided laser ablation systems are now feasible for dentistry with the recent development of nondestructive high-contrast imaging modalities such as near-IR (NIR) imaging and optical coherence tomography (OCT) that are capable of discriminating between sound and demineralized dental enamel at the early stages of development. Our objective is to demonstrate that images of demineralized tooth surfaces have sufficient contrast to be used to guide a CO2 laser for the selective removal of natural and artificial caries lesions. NIR imaging and polarization-sensitive optical coherence tomography (PS-OCT) operating at 1310-nm are used to acquire images of natural lesions on extracted human teeth and highly patterned artificial lesions produced on bovine enamel. NIR and PS-OCT images are analyzed and converted to binary maps designating the areas on the samples to be removed by a CO2 laser to selectively remove the lesions. Postablation NIR and PS-OCT images confirmed preferential removal of demineralized areas with minimal damage to sound enamel areas. These promising results suggest that NIR and PS-OCT imaging systems can be integrated with a CO2 laser ablation system for the selective removal of dental caries.
An efficient layer assignment algorithm for gridless switchbox routing

A graph-theoretic algorithm is presented for the layer assignment and via minimization of a gridless switchbox routing. A concept called via propagation is used to facilitate the minimization of vias. The time complexity of the proposed algorithm is O( n log n + K ), where n is the number of routing wire segments in the layout and K is the maximum number of vias that can occur. The approach achieves the minimum number of vias for several difficult switchbox problems
The Effects of Information and Augmentative Communication Technique on Attitudes toward Nonspeaking Individuals.

This study investigated the effects of printed factual information and three augmentative communication techniques on attitudes of nondisabled individuals toward nonspeaking persons with physical d...
International collaborations in nursing research Priorities, challenges and rewards

The purpose of this paper is to present a framework for dialogue for university-based nursing programmes that are planning and developing international research programmes. Future trends will continue to drive the need for international research due to the globalisation of healthcare issues. Nursing, as one of the main providers of healthcare services, can play a larger role in improving healthcare globally, by leading the way in international collaborative research. A definition of international nursing research is offered, as well as a framework consisting of three broad issues for discussing international work. The three foci of the framework are (a) international nursing research priorities, (b) rewards of international nursing collaborations and (c) challenges of these collaborations. Examples of international collaborative nursing research experiences with nurses in Haiti, Taiwan, Thailand and the United Kingdom are examined, along with lessons learned