Measurement of Motion beyond the Quantum Limit by Transient Amplification.

Through simultaneous but unequal electromechanical amplification and cooling processes, we create a method for a nearly noiseless pulsed measurement of mechanical motion. We use transient electromechanical amplification (TEA) to monitor a single motional quadrature with a total added noise -8.5±2.0 dB relative to the zero-point motion of the oscillator, or equivalently the quantum limit for simultaneous measurement of both mechanical quadratures. We demonstrate that TEA can be used to resolve fine structure in the phase space of a mechanical oscillator by tomographically reconstructing the density matrix of a squeezed state of motion. Without any inference or subtraction of noise, we directly observe a squeezed variance 2.8±0.3 dB below the oscillator's zero-point motion.

Quantum-enabled temporal and spectral mode conversion of microwave signals.

Electromagnetic waves are ideal candidates for transmitting information in a quantum network as they can be routed rapidly and efficiently between locations using optical fibres or microwave cables. Yet linking quantum-enabled devices with cables has proved difficult because most cavity or circuit quantum electrodynamics systems used in quantum information processing can only absorb and emit signals with a specific frequency and temporal envelope. Here we show that the temporal and spectral content of microwave-frequency electromagnetic signals can be arbitrarily manipulated with a flexible aluminium drumhead embedded in a microwave circuit. The aluminium drumhead simultaneously forms a mechanical oscillator and a tunable capacitor. This device offers a way to build quantum microwave networks using separate and otherwise mismatched components. Furthermore, it will enable the preparation of non-classical states of motion by capturing non-classical microwave signals prepared by the most coherent circuit quantum electrodynamics systems.

Current concepts in airway management for cardiopulmonary resuscitation.

OBJECTIVE: To describe the methods of maintaining airway patency for oxygenation during cardiopulmonary resuscitation (CPR) that do not require expertise in mask ventilation or endotracheal intubation by direct laryngoscopy. DESIGN: A review of rescue breathing and newer methods of providing airway patency is provided. RESULTS: Airway patency during CPR is often difficult to achieve. Mask ventilation predisposes to hypoventilation and aspiration pneumonitis. Endotracheal intubation by direct laryngoscopy is the preferred method of maintaining airway patency for CPR. Alternative techniques for airway management include endotracheal intubation by lighted stylet, esophageal tracheal Combitube, laryngeal mask airway, and transtracheal ventilation. These methods are recommended by the American Heart Association and the American Society of Anesthesiologists. They have been approved by the Food and Drug Administration for maintenance of airway patency; they are easy to learn, effective, and applicable to CPR. Advantages and disadvantages of each technique may indicate or contraindicate one method over another in specific circumstances. CONCLUSION: When CPR is compromised by airway obstruction that remains unresponsive to traditional techniques, using alternative methods is appropriate. The techniques selected must be based on individual familiarity and expertise.

Sensory blockade for difficult passage of transesophageal echocardiography probes.

During transesophageal echocardiography probe passage, airway reflexes are usually obtunded with topical local anesthetics. This technique meets with varying degrees of success. Even partially intact airway reflexes result in coughing, retching, and withdrawal, which may prevent transesophageal echocardiography examination or predispose to life-threatening tachycardia and hypertension. Proper preparation of the patient enhances comfort and helps protect against tachycardia and hypertension as well as reducing the time required for examination. This article outlines specific monitoring issues and offers precautions that are critical to transesophageal echocardiography probe passage. It suggests a premedication regimen and describes methods of sedation. Furthermore, it outlines the afferent innervation of the upper airway and specific techniques of temporary reflex interruption.

Cloning and sequence analysis of the spike gene from several feline coronaviruses.

The DNA sequence encoding the spike gene from the DF2 strain of Type II feline infectious peritonitis virus (FIPV), a temperature sensitive FIPV virus (TS-DF2) and an isolate of feline enteric coronavirus (FECV 1683) were determined. Comparison of the published WSU 1146 and DF2 FIPV S genes showed that the viruses shared a high degree of homology (99.6%). Likewise, the S gene of the virulent DF2 FIPV virus was closely conserved to that isolated from the vaccine virus strain, TS-DF2 FIPV. In contrast, the FECV S gene had numerous DNA and amino acid differences when compared to the virulent FIPV sequences. Sequence differences among the feline coronavirus isolates were localized to the amino-terminus region of the S gene.

Cloning and expression of FECV spike gene in vaccinia virus. Immunization with FECV S causes early death after FIPV challenge.

The spike gene of the feline enteric coronavirus (FECV), strain FECV-1683, was PCR amplified from total RNA extracted from FECV-infected cells and its sequence determined. A primary translation product of 1454 amino acids is predicted from the nucleotide sequence, containing a N-terminal signal sequence, a C-terminal transmembrane region and 33 potential N-glycosylation sites. The sequence shares 92% homology with the previously published feline infectious peritonitis virus, strain WSU-1146; however, several regions were identified that distinguished FECV from Feline Infectious Peritonitis virus, FIPV. The full length FECV S gene was cloned and expressed in vaccinia virus. Recombinants produced a 200 kD protein which was recognized by sera from cats infected with FIPV. When kittens were immunized with the vaccinia/FECV S recombinant, neutralizing antibodies to FIPV were induced. After challenge with a lethal dose of FIPV, the recombinant vaccinated animals died earlier than control animals immunized with vaccinia virus alone.

Ascending back pain and headache during attempted epidural placement.

A 30-year-old parturient requested epidural analgesia during labor. Immediately after the epidural space was presumably identified using the loss-of-resistance-to-air technique, she reported severe back pain, followed by neck pain, which progressed to severe unrelenting headache. An emergency computerized tomographic (CT) scan performed during labor showed air in the intracranial subarachnoid space.

Formal instruction in difficult airway management. A survey of anesthesiology residency programs.

BACKGROUND: Up to 30% of all deaths attributable to anesthesia are related to difficulties with airway management. The purpose of this study was to determine whether anesthesiology residents are receiving specialized instruction in the various techniques and mechanical devices currently recommended for airway management in patients with anticipated or unanticipated difficult airways. METHODS: A single anonymous questionnaire about resident instruction in the area of difficult airway management was mailed to the directors of 169 American anesthesiology programs. RESULTS: Twenty-seven percent of the 143 programs from which there were responses require residents to participate in a rotation dedicated to management of the difficult airway. As they currently exist, rotations tend to be of short duration. Many are limited to lectures only and infrequently employ state-of-the-art teaching systems. In some programs, recognized airway management techniques such as the Bullard laryngoscope and esophageal-tracheal combitube are not taught at all. CONCLUSIONS: Based on the data obtained by the authors, formal instruction in difficult airway management is not offered by most residency programs. It is commonly taught as difficult clinical situations arise. Because these difficulties occur sporadically, opportunities for teaching are occasional. Learning based on sporadic and occasional occurrences risks incomplete and nonuniform training of residents.

Nucleotide sequence and genome organization of canine parvovirus.

The genome of a canine parvovirus isolate strain (CPV-N) was cloned, and the DNA sequence was determined. The entire genome, including ends, was 5,323 nucleotides in length. The terminal repeat at the 3' end of the genome shared similar structural characteristics but limited homology with the rodent parvoviruses. The 5' terminal repeat was not detected in any of the clones. Instead, a region of DNA starting near the capsid gene stop codon and extending 248 base pairs into the coding region had been duplicated and inserted 75 base pairs downstream from the poly(A) addition site. Consensus sequences for the 5' donor and 3' acceptor sites as well as promotors and poly(A) addition sites were identified and compared with the available information on related parvoviruses. The genomic organization of CPV-N is similar to that of feline parvovirus (FPV) in that there are two major open reading frames (668 and 722 amino acids) in the plus strand (mRNA polarity). Both coding domains are in the same frame, and no significant open reading frames were apparent in any of the other frames of both minus and plus DNA strands. The nucleotide and amino acid homologies of the capsid genes between CPV-N and FPV were 98 and 99%, respectively. In contrast, the nucleotide and amino acid homologies of the capsid genes for CPV-N and CPV-b (S. Rhode III, J. Virol. 54:630-633, 1985) were 95 and 98%, respectively. These results indicate that very few nucleotide or amino acid changes differentiate the antigenic and host range specificity of FPV and CPV.

Biological evaluation of glycoproteins mapping to two distinct mRNAs within the BamHI fragment 7 of pseudorabies virus: expression of the coding regions by vaccinia virus.

Several glycoproteins from the unique short region of pseudorabies have been identified and characterized. The genes encoding at least four glycoproteins (gp50, gp63, gl, and gX) are located within the BamHI fragment 7 of pseudorabies. S1 nuclease mapping was used to determine that a 2.4-kb mRNA encompasses the coding region for gp50 and gp63 and probably represents a colinear transcript for these proteins. Using the same technique, a 2.8-kb mRNA was found to encode gl. No other mRNAs were found to be encoded on the opposite strand of DNA in this region. Various recombinant vaccinia vectors were made incorporating the coding regions for these two mRNAs. Pseudorabies recombinant vaccinia infected ST cells expressed glycoproteins that co-migrated with the authentic PRV glycoproteins upon polyacrylamide electrophoresis. Intracranial or intraperitoneal inoculation of mice with the recombinant viruses constructed to contain the mRNA coding regions resulted in various degrees of protection from a lethal challenge of pseudorabies virus.

Serological recognition of feline infectious peritonitis virus spike gene regions expressed as synthetic peptides and E. coli fusion protein.

Cats exposed to feline infectious peritonitis virus (FIPV) or feline enteric coronavirus (FECV) cannot be differentiated by serological analysis. Three synthetic peptides and an E. coli recombinant fusion protein generated from FIPV 79-1146 spike gene sequence were produced. Coronavirus positive cat sera reacted to peptide aa 950-990 but were non-reactive to aa137-151 and aa 150-180 peptides as demonstrated by ELISA. Amino acid sequence 97-222 expressed as a galk fusion protein in E. coli was tested against coronavirus positive cat sera by western blot analysis. Only sera from cats exposed to the FIPV type-II strains DF-2 or 79-1146 that were exhibiting signs of FIP recognized the fusion protein. Sera from FECV exposed cats did not recognize the 97-222 fusion protein in western blot analysis.