Nondestructive SEM for surface and subsurface wafer imaging

The scanning electron microscope (SEM) is considered as a tool for both failure analysis as well as device characterization. A survey is made of various operational SEM modes and their applicability to image processing methods on semiconductor devices

Alanine Racemase Mutants of Burkholderia pseudomallei and Burkholderia mallei and Use of Alanine Racemase as a Non-Antibiotic-Based Selectable Marker

Burkholderia pseudomallei and Burkholderia mallei are category B select agents and must be studied under BSL3 containment in the United States. They are typically resistant to multiple antibiotics, and the antibiotics used to treat B. pseudomallei or B. mallei infections may not be used as selective agents with the corresponding Burkholderia species. Here, we investigated alanine racemase deficient mutants of B. pseudomallei and B. mallei for development of non-antibiotic-based genetic selection methods and for attenuation of virulence. The genome of B. pseudomallei K96243 has two annotated alanine racemase genes (bpsl2179 and bpss0711), and B. mallei ATCC 23344 has one (bma1575). Each of these genes encodes a functional enzyme that can complement the alanine racemase deficiency of Escherichia coli strain ALA1. Herein, we show that B. pseudomallei with in-frame deletions in both bpsl2179 and bpss0711, or B. mallei with an in-frame deletion in bma1575, requires exogenous d-alanine for growth. Introduction of bpsl2179 on a multicopy plasmid into alanine racemase deficient variants of either Burkholderia species eliminated the requirement for d-alanine. During log phase growth without d-alanine, the viable counts of alanine racemase deficient mutants of B. pseudomallei and B. mallei decreased within 2 hours by about 1000-fold and 10-fold, respectively, and no viable bacteria were present at 24 hours. We constructed several genetic tools with bpsl2179 as a selectable genetic marker, and we used them without any antibiotic selection to construct an in-frame ΔflgK mutant in the alanine racemase deficient variant of B. pseudomallei K96243. In murine peritoneal macrophages, wild type B. mallei ATCC 23344 was killed much more rapidly than wild type B. pseudomallei K96243. In addition, the alanine racemase deficient mutant of B. pseudomallei K96243 exhibited attenuation versus its isogenic parental strain with respect to growth and survival in murine peritoneal macrophages

Long-term outcomes following H-type tracheoesophageal fistula repair in infants

PURPOSE: To evaluate outcomes following repair of H-type tracheoesophageal fistula (TEF). METHODS: Retrospective chart review of infants with H-type TEF treated at our institution between 2000 and 2014. Patient demographics, surgical management, and postoperative function were evaluated. RESULTS: Of the 268 patients with esophageal atresia/TEF treated at our center, 16 (6%) had an H-type TEF (10 males). Thirteen (81%) had associated anomalies. All patients were symptomatic: choking and sputtering were the most common presentation (n = 10, 63%). Diagnosis Age at diagnosis was 8 days (1 day-34 months). All patients were diagnosed based on a single esophagogram. Prior to surgery, 12 (75%) patients underwent bronchoscopy and 11 underwent cannulation of the TEF tract. Surgery All patients underwent open repair. One was started thoracoscopically but converted to open due to esophageal sero-muscular injury. Repair was achieved in all patients via a transcervical approach (right-sided incision in 15). One patient had an unsuccessful prior attempt at repair using tissue glue. Following TEF division, 11 patients had tissue interposition grafts placed (9 muscle, 2 fat). Postoperative course Eight (50%) patients had postoperative vocal cord paresis (6 right-sided, 2 bilateral). A patient developed recurrent TEF 78 days postoperatively that was subsequently repaired. Follow-up At 41 months (8-143), there were no mortalities, all patients with vocal cord paresis were asymptomatic despite the fact that only 3 of 8 (38%) regained function, and nine (56%) patients had gastro-esophageal reflux requiring treatment. CONCLUSIONS: This large, single-center series demonstrates that H-type TEF can be diagnosed with esophagogram at an early age. Postoperative recurrent laryngeal nerve paresis and gastro-esophageal reflux disease are common following repair. Although most patients with vocal cord paresis eventually become asymptomatic, two-thirds do not regain vocal cord function. This reinforces the importance of routine examination of vocal cord movement following H-type TEF repai

Competency-Based Assessment Tool for Pediatric Esophagoscopy: International Modified Delphi Consensus.

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/167424/1/lary29126.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/167424/2/lary29126_am.pd

Competency-Based Assessment Tool for Pediatric Tracheotomy: International Modified Delphi Consensus.

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/163458/2/lary28461.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/163458/1/lary28461_am.pd