Development and use of a high-fidelity simulator for fetal endotracheal balloon occlusion (FETO) insertion and removal.

Objectives The objective of this article is to describe the development of an anatomically accurate simulator in order to aid the training of a perinatal team in the insertion and removal of a fetal endoscopic tracheal occlusion (FETO) balloon in the management of prenatally diagnosed congenital diaphragmatic hernia. Methods An experienced perinatal team collaborated with a medical sculptor to design a fetal model for the FETO procedure. Measurements derived from 28-week fetal magnetic resonance imaging were used in the development of an anatomically precise simulated airway within a silicone rubber preterm fetal model. Clinician feedback was then used to guide multiple iterations of the model with serial improvements in the anatomic accuracy of the simulator airway. Results An appropriately sized preterm fetal mannequin with a high-fidelity airway was developed. The team used this model to develop surgical skills with balloon insertion, and removal, and to prepare the team for an integrated response to unanticipated delivery with the FETO balloon still in situ. Conclusions This fetal mannequin aided in the ability of a fetal therapy unit to offer the FETO procedure at their center for the first time. This model may be of benefit to other perinatal centers planning to offer this procedure.

Downsizing, job insecurity and firm reputation

This paper studies how firms make layoff decisions in the presence of adverse shocks. In this uncertain environment, workers' expectations about their job security affect their on-the-job performance. This productivity effect on job insecurity forces firms to strike a balance between laying off redundant workers and maintaining survivors' commitment when deciding on the amount and timing of downsizing. This framework offers an explanation of conservative employment practices (such as zero or reduced layoffs) based on firms having private information about their future profits. High retention rates and wages can signal that the firm has a bright future, boosting workers' confidence. Moreover, the model provides clear predictions about when waves of downsizing will occur as opposed to one-time massive cuts.

A simple optimised search heuristic for the job-shop scheduling problem

This paper presents a simple Optimised Search Heuristic for the Job Shop Scheduling problem that combines a GRASP heuristic with a branch-and-bound algorithm. The proposed method is compared with similar approaches and leads to better results in terms of solution quality and computing times.

Job dynamics, correlated shocks and wage profiles

We generalize the Mortensen-Pissarides (1994) model of the labor marketwith a more realistic structure for the stochastic process of theshocks to the worker-firm match. In this way we can acommodate theempirical observation that hazard rates of job termination decrease andaverage wages increase with job tenure. Besides being able to fit bettersome observables of the model, the changes we introduce are nontrivialfor the analysis of policies as well.

Non-stationary job search when jobs are not forever: A structural estimation

This paper considers a job search model where the environment is notstationary along the unemployment spell and where jobs do not lastforever. Under this circumstance, reservation wages can be lower thanwithout separations, as in a stationary environment, but they can alsobe initially higher because of the non-stationarity of the model. Moreover,the time-dependence of reservation wages is stronger than with noseparations. The model is estimated structurally using Spanish data forthe period 1985-1996. The main finding is that, although the decrease inreservation wages is the main determinant of the change in the exit ratefrom unemployment for the first four months, later on the only effect comesfrom the job offer arrival rate, given that acceptance probabilities areroughly equal to one.

Job search and asset accumulation under borrowing constraints

In this paper I show how borrowing constraints and job search interact.I fit a dynamic model to data from the National Longitudinal Survey(1979-cohort) and show that borrowing constraints are significant. Agentswith more initial assets and more access to credit attain higher wagesfor several periods after high school graduation. The unemployed maintaintheir consumption by running down their assets, while the employed saveto buffer against future unemployment spells. I also show that, unlikein models with exogenous income streams, unemployment transfers, byallowing agents to attain higher wages do not 'crowd out' but increasesaving.

Complete Nucleotide Sequence of Mouse Mammary Tumor Virus from JYG Chinese Wild Mice: Absence of Bacterial Insertion Sequences in the Cloned Viral gag Gene.

Mammary tumors of a newly isolated strain of Chinese wild mouse (JYG mouse) harbor exogenous mouse mammary tumor virus (MMTV). The complete nucleotide sequence of exogenous JYG-MMTV was determined on the proviral 5' long terminal repeat (LTR)(partial)-gag-pol-env-3' LTR (partial) fragment cloned into a plasmid vector and the cDNA sequence from JYG-MMTV producing cells. Similarly to the other MMTV species the LTR of JYG-MMTV contains an open reading frame (ORF). The amino acid sequence of the JYG-MMTV ORF resembles that of SW-MMTV (92% identity) and endogenous Mtv-7 (93% identity) especially at the C-terminal region. Thus, a functional similarity in T-cell receptor V beta recognition as a superantigen is implicated among these MMTV species. Analysis of the viral gag nucleotide sequence revealed that this gene is not disrupted by the bacterial insertion sequence IS1 or IS2, which have been reported to be present in the majority of the plasmids containing the gag region. Comparison of amino acid sequences of JYG-MMTV with those of BR6-MMTV showed that over 96% of the amino acids of gag, pol, protease and env products are identical. These results suggest the intact nature of the nucleotide sequence of the near full-length MMTV genome cloned in the plasmid.

Job cum glosa

Abbaye de Saint-Victor de Paris

Sampling and TDR probe insertion in the determination of the volumetric soil water content

Volumetric soil water content (theta) can be evaluated in the field by direct or indirect methods. Among the direct, the gravimetric method is regarded as highly reliable and thus often preferred. Its main disadvantages are that sampling and laboratory procedures are labor intensive, and that the method is destructive, which makes resampling of a same point impossible. Recently, the time domain reflectometry (TDR) technique has become a widely used indirect, non-destructive method to evaluate theta. In this study, evaluations of the apparent dielectric number of soils (epsilon) and samplings for the gravimetrical determination of the volumetric soil water content (thetaGrav) were carried out at four sites of a Xanthic Ferralsol in Manaus - Brazil. With the obtained epsilon values, theta was estimated using empirical equations (thetaTDR), and compared with thetaGrav derived from disturbed and undisturbed samples. The main objective of this study was the comparison of thetaTDR estimates of horizontally as well as vertically inserted probes with the thetaGrav values determined by disturbed and undisturbed samples. Results showed that thetaTDR estimates of vertically inserted probes and the average of horizontally measured layers were only slightly and insignificantly different. However, significant differences were found between the thetaTDR estimates of different equations and between disturbed and undisturbed samples in the thetaGrav determinations. The use of the theoretical Knight et al. model, which permits an evaluation of the soil volume assessed by TDR probes, is also discussed. It was concluded that the TDR technique, when properly calibrated, permits in situ, nondestructive measurements of q in Xanthic Ferralsols of similar accuracy as the gravimetric method.

Characterization of the staphylococcal cassette chromosome mec insertion site in 108 isolates lacking the mecA gene and identified as methicillin-resistant Staphylococcus aureus by the Xpert MRSA assay.

During a 3-year period, 848 patients were detected as carriers of methicillin-resistant Staphylococcus aureus (MRSA) by the Xpert MRSA assay (Cepheid). Among them, 108 patients (12.7 %) were colonized with strains showing methicillin-susceptible phenotypes and absence of the mecA gene, despite being positive with the rapid polymerase chain reaction (PCR) assay. DNA sequences of the staphylococcal cassette chromosome mec (SCCmec) insertion site of these "false-positive" strains was determined by direct sequencing of the genomic DNA. More than half (53.7 %) of the strains had DNA sequences unrelated to either SCC or SCCmec and one-third had DNA sequences related to non-mec SCC. Only 10.2 % of the strains carried sequences related to SCCmec, suggesting that a sequence containing the mecA gene was lost from an SCCmec. These findings differ from the general idea that all methicillin-susceptible S. aureus having positive Xpert MRSA assay results are essentially MRSA that lost the mecA gene.

Safety and accuracy of robot-assisted versus fluoroscopy-guided pedicle screw insertion for degenerative diseases of the lumbar spine: a matched cohort comparison.

Object Recent years have been marked by efforts to improve the quality and safety of pedicle screw placement in spinal instrumentation. The aim of the present study is to compare the accuracy of the SpineAssist robot system with conventional fluoroscopy-guided pedicle screw placement. Methods Ninety-five patients suffering from degenerative disease and requiring elective lumbar instrumentation were included in the study. The robot cohort (Group I; 55 patients, 244 screws) consisted of an initial open robot-assisted subgroup (Subgroup IA; 17 patients, 83 screws) and a percutaneous cohort (Subgroup IB, 38 patients, 161 screws). In these groups, pedicle screws were placed under robotic guidance and lateral fluoroscopic control. In the fluoroscopy-guided cohort (Group II; 40 patients, 163 screws) screws were inserted using anatomical landmarks and lateral fluoroscopic guidance. The primary outcome measure was accuracy of screw placement on the Gertzbein-Robbins scale (Grade A to E and R [revised]). Secondary parameters were duration of surgery, blood loss, cumulative morphine, and length of stay. Results In the robot group (Group I), a perfect trajectory (A) was observed in 204 screws (83.6%). The remaining screws were graded B (n = 19 [7.8%]), C (n = 9 [3.7%]), D (n = 4 [1.6%]), E (n = 2 [0.8%]), and R (n = 6 [2.5%]). In the fluoroscopy-guided group (Group II), a completely intrapedicular course graded A was found in 79.8% (n = 130). The remaining screws were graded B (n = 12 [7.4%]), C (n = 10 [6.1%]), D (n = 6 [3.7%]), and E (n = 5 [3.1%]). The comparison of "clinically acceptable" (that is, A and B screws) was neither different between groups (I vs II [p = 0.19]) nor subgroups (Subgroup IA vs IB [p = 0.81]; Subgroup IA vs Group II [p = 0.53]; Subgroup IB vs Group II [p = 0.20]). Blood loss was lower in the robot-assisted group than in the fluoroscopy-guided group, while duration of surgery, length of stay, and cumulative morphine dose were not statistically different. Conclusions Robot-guided pedicle screw placement is a safe and useful tool for assisting spine surgeons in degenerative spine cases. Nonetheless, technical difficulties remain and fluoroscopy backup is advocated.

Hereditary hepatic and systemic amyloidosis caused by a new deletion/insertion mutation in the apolipoprotein AI gene.

We report a Spanish family with autosomal-dominant non-neuropathic hereditary amyloidosis with a unique hepatic presentation and death from liver failure, usually by the sixth decade. The disease is caused by a previously unreported deletion/insertion mutation in exon 4 of the apolipoprotein AI (apoAI) gene encoding loss of residues 60-71 of normal mature apoAI and insertion at that position of two new residues, ValThr. Affected individuals are heterozygous for this mutation and have both normal apoAI and variant molecules bearing one extra positive charge, as predicted from the DNA sequence. The amyloid fibrils are composed exclusively of NH2-terminal fragments of the variant, ending mainly at positions corresponding to residues 83 and 92 in the mature wild-type sequence. Amyloid fibrils derived from the other three known amyloidogenic apoAI variants are also composed of similar NH2-terminal fragments. All known amyloidogenic apoAI variants carry one extra positive charge in this region, suggesting that it may be responsible for their enhanced amyloidogenicity. In addition to causing a new phenotype, this is the first deletion mutation to be described in association with hereditary amyloidosis and it significantly extends the value of the apoAI model for investigation of molecular mechanisms of amyloid fibrillogenesis.