Spatial modifications of a Gaussian beam incident on a diffraction grating.

When a fundamental Gaussian beam at microwave frequency is incident on a reflection grating, there are spatial modifications such as lateral shift for the reflected and diffracted beam and generation of higher order Gaussian modes. Different parameters of the incident beam such as waist radius, beam frequency, incident angle, and polarization direction affect the spatial modifications differently. We trace the beam propagation and central ray position by simulation and find how these parameters influence the beam modifications.

Implementation of a multidisciplinary program for active duty personnel seeking care for low back pain in a U.S. Navy Medical Center: a feasibility study.

The aim of the pilot study was to evaluate a multidisciplinary program for nonspecific low back pain (NSLBP) at a major U.S. Navy base. In this single blinded randomized clinical trial, subjects were drawn from a larger, prospective cohort of active duty service members seeking care for NSLBP pain at a U.S. Navy Branch Medical Clinic. Outcome measures included return to work, self-reported pain, function, and psychological distress. Subjects were randomly allocated to one of two study arms: a multidisciplinary reconditioning program or the current standard of care for low back pain. The intervention lasted 4 weeks with a 12-week follow-up. Thirty-three subjects were enrolled. Subjects allocated to multidisciplinary care reported significantly lower perceived disability (p = 0.014) and less pain than those allocated to usual care at the end of the intervention period. All subjects returned to their usual duty following the conclusion of the intervention. The implementation of the intervention program was successful. Subjects in the multidisciplinary program showed a clinically significant improvement in the perception of disability compared to the usual care group. This is an important finding since perception of disability is associated with long-term functional outcome.

Predictors of short-term work-related disability among active duty US Navy personnel: a cohort study in patients with acute and subacute low back pain.

BACKGROUND CONTEXT: Musculoskeletal disorders of the spine in the US military account for the single largest proportion of the absence of sickness causes leading to early termination. We explored if selected psychological and physical factors were associated with poor outcome after episodes of low back pain (LBP). PURPOSE: To identify clinical, demographic, and psychological factors predictive of work duty status after a complaint of LBP. STUDY DESIGN: A prospective clinical cohort of US Navy personnel treated for LBP. PATIENT SAMPLE: Eligible cases were active duty US Navy or Marine Corps personnel presenting to an emergency clinic or primary care clinic with a complaint of LBP, where the index episode of LBP was no more than 12 weeks duration before enrollment. OUTCOME MEASURES: The subject's work status (full duty, light duty, sick in quarters [SIQ], limited duty, or medically released to full duty) was abstracted from the subject's electronic medical record at approximately 4 weeks and then again 12 weeks after study enrollment. Work status in this study population is assigned by a Navy health-care provider at the time of a clinical visit and based on the health-care provider's determination of medical fitness for duty. This study collapsed work status into two groups, "full duty" (consisting of "full duty" and "medically released to full duty") and "not at full duty" (consisting of "light duty," "SIQ," and "limited duty"). METHODS: Volunteers completed a baseline questionnaire consisting of recommended well-validated measures, including attitudes and beliefs about LBP and work (Fear-Avoidance Beliefs Questionnaire [FABQ] and the Tampa Scale of Kinesiophobia), distress (the Pain Catastrophizing Scale), clinical depression (The Center for Epidemiologic Studies Depression scale), a numeric pain intensity scale, self-perceived disability (Oswestry Disability Index), and general health status (12-Item Short Form Health Survey). Navy health-care providers conducted a back pain-specific medical evaluation. Associations are expressed as multivariate-adjusted prevalence ratios (PRs) estimated using Poisson regression. RESULTS: Two hundred fifty-three participants were enrolled. Work status outcome was collected for 239 participants. Predictors of "not at full duty" at 4 weeks after enrollment included having back pain for 4 weeks or less before study enrollment (PR, 2.69; 95% CI, 1.21-5.97) and increased FABQ Work subscale score (PR, 1.05; 95% CI, 1.01-1.08). The sole predictor of work status at 12 weeks after enrollment was increased FABQ Physical Activity (FABQ Physical) subscale score (PR=1.14; 95% CI, 1.00-1.30). CONCLUSIONS: The findings that fear-avoidance beliefs were predictive of subsequent work status among active duty service personnel in this study population (after adjusting for clinical, demographic, and psychological covariates) suggest the clinical utility of addressing these factors during treatment of back pain episodes in the military. These findings reflect the important role that psychological factors may play in the return to work process in an active duty military population.

Generation and identification of variants with improved purification yield of Bowman-Birk protease inhibitors carrying protein binding loops.

Replacing the chymotrypsin inhibitory loop of soybean Bowman-Birk inhibitor (sBBI) with a VEGF binding peptide (BBI-AV) significantly reduces the overall purification yield when BBI-AV is produced as a fusion protein in a Bacillussubtilis expression system. The low purification yield is primarily due to a higher fraction of molecules with incorrect disulfide bond configurations after production and also after disulfide bond shuffling induced by 2-mercaptoethanol. To improve production yields, site-saturation libraries were generated at 39 out of the 66 amino acid residues of BBI-AV. Initial screens were designed to select for variants with higher trypsin inhibitory activities than the parent after treatment with a reducing agent. Secondary screens were developed to select for variants with the highest purification yields, and to also eliminate any false positives. From the screens, it was found that positively charged substitutions in the exposed hydrophobic patch region (sites 27, 29, 40, 50 & 52) are especially productive. In fact, one substitution, F50R, improves the purification yield to nearly the same level as wild-type sBBI. Productive amino acid substitutions were combined to select for the variant with the best overall yield after purification. Several variants were obtained with higher purification yields than even sBBI. The octuple variants, A13I-S25R-M27A-L29P-S31A-A40H-F50K-V52T and A13I-S25K-M27A-L29R-S31E-A40K-F50Q-V52Q, are particularly productive having greater than a five fold increase in final purification yield over the parent.

Olecranon fracture fixation utilizing a bioabsorbable tension band construct: analysis of stability with motion in a cadaveric model.

This study was performed to determine if tension band suturing with bioabsorbable materials can maintain fracture (osteotomy) reduction when subjected to an early motion protocol. Olecranon osteotomies were created in 13 cadaveric upper extremities and then sequentially fixed with axial Kirschner wires, and tension band wiring/suturing utilizing: musical #1 PDS (Ethicon Inc., Somerville, New Jersey, USA), musical #1 Panacryl (Ethicon Inc.), musical #2 Panacryl (Ethicon Inc.), and 18 gauge surgical wire. Specimens were cycled through a range of motion in a continuous passive motion machine. Specimens fixed with K-wires only, musical #1PDS and musical #1 Panacryl tension band suturing failed to maintain osteotomy reduction. Only surgical steel and musical #2 Panacryl maintained osteotomy reduction; both were superior to the other fixation methods (P<0.001). The musical #2 Panacryl suture is an excellent choice for a tension band suture construct; it retains 80% of its breaking strength at 3 months, is fully absorbed, and maintains osteotomy reduction throughout a passive motion protocol.

Characterization of humanized antibodies secreted by Aspergillus niger.

Two different humanized immunoglobulin G1(kappa) antibodies and an Fab' fragment were produced by Aspergillus niger. The antibodies were secreted into the culture supernatant. Both light and heavy chains were initially synthesized as fusion proteins with native glucoamylase. After antibody assembly, cleavage by A. niger KexB protease allowed the release of free antibody. Purification by hydrophobic charge induction chromatography proved effective at removing any antibody to which glucoamylase remained attached. Glycosylation at N297 in the Fc region of the heavy chain was observed, but this site was unoccupied on approximately 50% of the heavy chains. The glycan was of the high-mannose type, with some galactose present, and the size ranged from Hex(6)GlcNAc(2) to Hex(15)GlcNAc(2). An aglycosyl mutant form of antibody was also produced. No significant difference between the glycosylated antibody produced by Aspergillus and that produced by mammalian cell cultures was observed in tests for affinity, avidity, pharmacokinetics, or antibody-dependent cellular cytotoxicity function.