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Development of chilling and freezing tolerance is complex and can be affected by photoperiod, temperature and photosynthetic performance; however, there has been limited research on the interaction of these three factors. We evaluated 108 recombinant inbred lines of Boechera stricta, derived from a cross between lines originating from Montana and Colorado, under controlled long day (LD), short-day (SD) and in an outdoor environment (OE). We measured maximum quantum yield of photosystem II, lethal temperature for 50% survival and electrolyte leakage of leaves. Our results revealed significant variation for chilling and freezing tolerance and photosynthetic performance in different environments. Using both single- and multi-trait analyses, three main-effect quantitative trait loci (QTL) were identified. QTL on linkage group (LG)3 were SD specific, whereas QTL on LG4 were found under both LD and SD. Under all conditions, QTL on LG7 were identified, but were particularly predictive for the outdoor experiment. The co-localization of photosynthetic performance and freezing tolerance effects supports these traits being co-regulated. Finally, the major QTL on LG7 is syntenic to the Arabidopsis C-repeat binding factor locus, known regulators of chilling and freezing responses in Arabidopsis thaliana and other species.

Objectives/Hypothesis To study the complication rates of skin overgrowth, infection, and the need for revision surgery in longer length Baha™ abutments. Study Design Prospective observational cohort study compared with a retrospective historical control. Methods After the University of Nebraska Medical Center (UNMC) Institutional Review Board approval was obtained, data was collected from a prospective 8.5-mm abutment study group of 21 subjects with informed consent from October 2011 through October 2012, and was compared to a retrospective 5.5-mm abutment historical cohort of 23 patients who had undergone Baha™ by the same surgeon from May 2010 to October 2011. Patient demographics, body mass index (BMI), smoking status, and wound complications (skin overgrowth, infection, the need for revision surgery) were statistically investigated and compared between the groups. Results Forty-four patients were studied. The groups were similar in smoking status, diabetes, and a female preponderance. The 8.5-mm abutment group was older (P = 0.012). The average BMI for both groups was classified as overweight and nearly obese (BMI 28.8). Rates of infection, skin overgrowth, and the need for revision surgery related to wound complications were significantly decreased in the longer 8.5-mm abutment group (P = 0.020, P = 0.012, P = 0.007, respectively). BMI did not correlate with decreased infection, skin overgrowth, and the need for revision surgery based on abutment length as hypothesized (P = 0.214, P = 0.206, P = 0.408). Conclusions The 8.5-mm abutment lends to decreased complications postoperatively, including infection, skin overgrowth, and the need for revision surgery. Level of Evidence 3b. Laryngoscope, 124:989–992, 2014

Objective. To compare postoperative pain scores between monopolar electrocautery and coblation subcapsular tonsillectomy.Study Design. Prospective double-blind randomized study.Setting. Tertiary care children’s hospital.Subjects and Methods. Between December 2004 and April 2008, 61 children, ages 4 to 20 years (mean age, 10 years; SD, 4 years), were randomized to have one tonsil removed by electrocautery and the other tonsil removed by coblation. Subjects used the FACES scale to rate pain on each side immediately postoperatively, 2 days postoperatively, and 2 weeks postoperatively. Postoperative hemorrhage was also tracked.Results. Coblation tonsillectomy resulted in statistically less pain than electrocautery immediately after surgery, but this difference was not clinically significant.Conclusions. Pediatric pain is similar following monopolar electrocautery or coblation subcapsular tonsillectomy.

Implant success is dependent in part on the interaction of the implant with the surrounding tissues. Porous tantalum implants (Trabecular Metal™, TM) have been shown to have excellent osseointegration. Machining this material to complex shapes with close tolerances is difficult because of its open structure and the ductile nature of metallic tantalum. Conventional machining results in occlusion of most of the surface porosity by the smearing of soft metal. This study compared TM samples finished by three processing techniques: conventional machining, electrical discharge machining, and nonmachined, “as-prepared.” The TM samples were studied in a rabbit distal femoral intramedullary osseointegration model and in cell culture. We assessed the effects of these machining methods at 4, 8, and 12 weeks after implant placement. The finishing technique had a profound effect on the physical presentation of the implant interface: conventional machining reduced surface porosity to 30% compared to bulk porosities in the 70% range. Bone ongrowth was similar in all groups, while bone ingrowth was significantly greater in the nonmachined samples. The resulting mechanical properties of the bone implant-interface were similar in all three groups, with only interface stiffness and interface shear modulus being significantly higher in the machined samples. © 2006 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2007

Objective Determine if passive smoke exposure (PSE) increases airway complications during outpatient mask anesthesia procedures in children. Methods A prospective cohort of children who underwent surgical procedures under mask anesthesia was studied with the American Thoracic Society children’s questionnaire on environmental and respiratory factors. Double-blinded outcomes with respect to adverse airway events were recorded both intraoperatively and in the recovery room for patients with and without passive smoke exposure. Multivariate comparisons assessing the likelihood of these airway complications were conducted between the PSE and nonexposed groups. Results Of 405 children, 168 (41.5%) had PSE. The incidence of airway complications during anesthesia or postanesthetic recovery was higher for all outcome measures for PSE children (all P ≤ 0.005), except for recovery room breath holding ( P = 0.086). Intraoperative laryngospasm and airway obstruction were 4.9 and 2.8 times more likely with PSE, respectively. Conclusions PSE significantly increases the risk of anesthesia-related airway complications during outpatient pediatric procedures. EBM rating: A-1b

Objective: To identify the most common otolaryngologic causes of mortality in the 0 to 19 age group in the state of Massachusetts and to estimate the pediatric otolaryngologic mortality rate based on population data. Study Design: Population-based retrospective cohort study. Methods: The Massachusetts State Registry of Vital Records and Statistics electronic database was searched for all otolaryngology related causes of death from 1990 to 2002 for children aged 0 to 19. The individual death certificates were then reviewed, and a database of otolaryngology related pediatric deaths was created. Results: A total of 59 otolaryngology related deaths were identified in the pediatric population from 1990 to 2002. Eighty-one percent of deaths occurred because of airway compromise caused by infection, anatomic obstruction, or congenital anomaly. The remaining 19% of deaths occurred because of aspiration, nonairway infections, and malignant neoplasms. Ninety-five percent of deaths in the children under age 10 were caused by airway compromise. Six of seven deaths (86%) in the age 15 to 19 group occurred because of malignant neoplasms. The overall mortality rate caused by otolaryngologic causes was estimated to be 0.28 per 100,000 population. Conclusions: The overall mortality rate for otolaryngology related deaths is low in the pediatric population. The vast majority of deaths are caused by airway compromise, primarily because of laryngotracheobronchitis or other upper airway obstruction. In older children (ages 15–19), malignant head and neck neoplasms are the leading cause of otolaryngology related deaths.

Choice of crops is limited in dry agro-ecosystems. Senna, Cassia angustifolia Vahl, a tropical medicinal plant, has potential as a dryland crop. This study was conducted to investigate gas exchange and leaf surface ultrastructural responses of senna to drought and foliar-applied nitrogen under greenhouse conditions. Drought was imposed cyclically as four, 1-wk spells by withholding water. Additional nitrogen was provided as a foliar treatment of 1% (w/v) urea at the end of each of first three drought cycles. Drought-stressed plants had the same net photosynthesis (P net ) as well-watered plants until the leaf water potential dropped below approximately -0.8 MPa. Leaf water potential of approximately - 2 MPa completely suppressed P net . Foliar nitrogen treatment increased P net > 30% in both water-stressed and well-watered plants. Intrinsic water use efficiency was unaffected by cyclic drought. Leaf area per plant increased 156% because of foliar nitrogen treatment in well-watered plants but remained unchanged in drought-stressed plants. Stomatal count per leaflet decreased 25% or more because of drought regardless of foliar nitrogen treatment on either abaxial or adaxial leaf surface. Foliar nitrogen treatment decreased adaxial but increased abaxial stomatal count regardless of drought treatment. Trichome count was more than eight times greater on the abaxial than the adaxial leaf surface under any treatment combination. Adaxial trichome number increased under drought, but decreased under nitrogen treatment. Abaxial trichome count increased because of drought only in plants deprived of nitrogen treatment. Maintenance of high carbon gain and water use efficiency, drought deciduousness, and plasticity in stomatal and trichome counts under both drought and nitrogen stress appeared to confer stress tolerance in senna.

Objective To describe the epidemiology, natural history, and treatment of epiglottitis in the Hemophilus influenzae type B (Hib) vaccine era. Design Ten-year retrospective study. Setting Tertiary-care children's hospital. Patients Nineteen patients with a discharge diagnosis of epiglottitis. Intervention As indicated by the presentation of the patient, including direct laryngoscopy, intubation, intravenous antibiotics, and steroids. Main outcome measures Presentation, management, and microbiology. Results Presenting symptoms included fever, drooling, and hot potato voice. Patients' ages ranged from 15.8 months to 17.5 (mean 8.9) years. From 1992 to 1997, the mean age was 5.8 years; from 1998 to 2002, the mean age was 11.6 years. Sixty-eight percent of patients were transferred from an outside hospital. A lateral neck radiograph was recorded in 84% of patients. Mean leukocyte count was 16,600. Direct laryngoscopy with intubation was performed in 79%; intubation was for an average of 3.5 days. H. influenzae was cultured in six patients, five of which had up-to-date immunizations. The most commonly administered antibiotics were ampicillin/sulbactam and ceftriaxone. Steroids were administered to 63% of patients. Complications included deep neck space infection (2), seizure (1), recurrent illness (1), and vocal granuloma (1). There were no deaths. Conclusion The demographics, causative organisms, and natural history of epiglottitis have changed substantially in the Hib vaccination era. The clinician evaluating and treating patients with epiglottitis should be aware of current trends.

The accumulation of damage and the associated degradation of the mechanical properties of cortical bone are postulated to contribute to age-, disease-, overuse-, and disuse-related skeletal fragilities. Therefore, gaining insight into the relationship between damage and degradation processes is essential in understanding the etiology of skeletal fractures. In investigating this relationship, the damage measure ideally needs to account for the size, the distribution density, and the orientation of microcracks. Existing measures of damage address the size and distribution density of microcracks; however, the orientation of cracks has not been well-investigated. Because the overall orientation of microcracks determines the material axis along which the greatest degradation will be experienced, we hypothesized that the incorporation of the relative orientation between microcracks and loading direction will improve the significance of the relationship between damage accumulation and material property degradation. A three-cycle damage protocol was used to induce tensile damage and to quantify the degradation of the elastic modulus of specimens from human donor femoral cortical bone (a 24-year-old and a 72-year-old man). Microcracks were evaluated by en bloc basic fuchsin staining of specimens after testing. The length (L(i)) and the orientation with respect to the loading direction (beta(i)) of each crack were quantified by a video microscopy system. Three damage measures were quantified for each specimen: the number of linear microcracks (Cr #), the sum of the crack lengths (SigmaL(i)) accounting for the microcrack size alone, and the sum of the projected crack length [SigmaL(Pi) = SigmaL(i)cos(beta(i))] accounting for both crack size and orientation. Inclusion of the orientation parameter improved the coefficient of determination between damage accumulation and the degradation of the elastic modulus: the coefficient of determination of the sum of the projected crack length (R(2) = 0.239) was 60% greater than that of the sum the projected crack length (R(2) = 0.149) and 33% greater than that of the number of linear microcracks (R(2) = 0.180). We conclude that microcrack orientation is an essential physical variable in the relationship between damage accumulation and degradation of mechanical properties of cortical bone tissue.

The purpose of this study was to compare the osseointegration of surface-blasted Ti6Al4V and CoCr implants in vivo. Ti6Al4V and CoCr rods blasted with 710 μm Al2O3 particles were bilaterally press-fit into the medullary space of distal femora of 24 rabbits. Evaluation was made radiographically, histologically, histomorphometrically (3, 6, and 12 weeks after implantation), and mechanically (12 weeks). Both Ti6Al4V and CoCr implants demonstrated good biocompatibility radiographically and histologically. Toluidine blue-stained sections revealed an osteoconductive effect of the blasted surface, and fluorochrome labeling analysis showed active bone formation at the bone–implant interface at as late as 12 weeks for both specimens. CoCr showed significantly lower interfacial shear strength than Ti6Al4V although the bone contact area with the implant surface was comparable and no intervening soft tissue at the bone–implant interface could be seen for either implant by scanning electron microscopy backscatter analysis. Unmineralized tissue (cartilage and osteoid) was observed more frequently on the CoCr surface than on the Ti6Al4V surface. These data show less osseointegration of CoCr implants with this blasted surface for this short period, possibly due to a slight difference in surface roughness and some negative effects of CoCr on bone attachment. © 1998 John Wiley & Sons, Inc. J. Biomed Mater Res, 42, 20–29, 1998.

Objectives:Evaluate the effect of increasing blood alcohol concentration (BAC) on the vestibular system as measured by abnormal body sway on posturography. Determine if there is a consistent level of BAC during which sway becomes adversely affected, as suggested by legal state limits of BAC for driving.Methods:Prospective study of 30 healthy adults randomized to alcohol versus no alcohol who consumed one beverage hourly followed by BAC measurement by BACtrack Select S80 Breathalyzer and posturography on both firm/soft surfaces with eyes open/closed. Primary outcome was dose-response rate of BAC on mean body sway. Nonlinear growth models were used to control for covariates.Results:The experimental (alcohol) group had 20 adults, and the control (no alcohol) group had 10 adults. BAC levels measured by breathalyzer ranged from 0 to 0.12. Overall analysis showed no statistically significant difference between male and female performance (P > 0.05). Increased alcohol consumption was associated with increased ab...

BACKGROUND In the 1980s, prostate specific antigen (PSA) came into wide use as a prostate carcinoma screening and detection method in the United States. Following the introduction of PSA, the age-adjusted incidence of prostate carcinoma reported by the Surveillance, Epidemiology, and End Results (SEER) program in the United States rose rapidly (from 84.4/100,000 in 1984 to 163/100,000 in 1991). When an increase in incidence is observed following the introduction of a screening method, a subsequent decrease in incidence may be expected as prevalent cases are removed from the population (a cull effect). Incidence rates may also fall due to factors such as decreased intensity of screening. The Utah Cancer Registry data were examined for a decrease in prostate cancer incidence. METHODS We tracked age-adjusted prostate carcinoma incidence trends from the population-based Utah Cancer Registry and compared them with rates from the SEER national registry. RESULTS A rapid and highly correlated rise in prostate carcinoma incidence has been observed in both SEER and Utah incidence rates between 1988 and 1991, the last year for which SEER data are available. In 1992, Utah incidence rates peaked at 236.2 per 100,000. In 1993 and 1994, Utah incidence rates fell to 195.0, and an estimated 164.0 per 100,000, respectively. CONCLUSIONS Population-based data from the Utah Cancer Registry indicates that the incidence of prostate carcinoma is decreasing rapidly after a similarly rapid increase. Cancer 1996;77:1342-8.

Retropatellar pain often accompanies malalignment syndromes and frequently is attributed to excessive patellofemoral contact stresses. Elevation (anterior displacement) of the tibial tubercle has been recommended to relieve these conditions. The degree to which patellar contact forces are decreased and the extent to which elevation alters medial-lateral forces have not been studied directly. We performed anterior translation of the tibial tubercle in knees from cadavers and measured the effect on the magnitude of the three-dimensional patellofemoral contact force with use of a specially designed 6-degrees-of-freedom force transducer, with the natural patellar articular surface in place. Measurements were made in nine knees (average age 67 years, range 46-92 years). The resultant contact force decreased linearly with increasing tubercle elevations of as much as 2.5 cm. The average reduction per centimeter of elevation was 17% of the force measured with no elevation. Elevation of the tubercle had an inconsistent effect on the medial-lateral component of the contact force. As the elevation was increased, six knees exhibited an increase in the medial-lateral component of the contact force acting medially on the knee and three knees exhibited a decrease in this force component. The results of this study show that, while elevation of the tubercle without medialization reduced the total contact force on the patella, the medial-lateral component of this force was altered in an unpredictable way.

M IN IS E M IN A R S stapedectomies in the past were undoubtedly performed on ears with occult third window syndromes. We will present a review of superior SCD and other third window syndromes, with an emphasis on differentiating them from more common otologic diagnoses. Cases will be presented that illustrate how these syndromes should be included in the differential diagnosis of many common otologic presentations. SCD, the most common third window syndrome, will be discussed in detail, including diagnosis and treatment indications, options, and outcomes.

Cerebrospinal fluid leaks can be difficult management problems. Little information has been published about handling these cases in the pediatric population. A review of cases over the past 10 years at Boston Children's Hospital was undertaken to identify any prognostic factors and therapeutic recommendations. Twenty-seven patients were identified. While most patients responded to conservative therapy, those with leaks that persisted longer than 8 days required some type of operative closure. Severity of injury had little correlation with the occurrence of a leak. The findings in this study indicate that most pediatric cases can be managed on a conservative basis.

As knee flexion increases, so do tendofemoral and patellofemoral compression forces. Three cases of long-standing uncorrected flexion contractures of the knees are presented that resulted in marked erosion of the femoral trochlea, patella baja, and remodeled patellar articular surfaces likely reflecting increased angles of flexion. It is probable that the deep femoral grooves are the result of adaptation under high-level persistent contact loads from the quadriceps tendon. These examples expand our knowledge of bone remodeling and offer information of potential use in studying ancient skeletal samples.

Trees of Sassafras albidum display leaves that fall into discrete categories of form. Unlobed leaves, with undissected margins, predominate at proximal and distal nodes of shoots, while lobed leaves are most common at intermediate nodes. In this study we investigated the hypothesis that shoots of sassafras respond to environmental changes over the growing season by generating predictable nodal patterns for leaf morphology and physiology. We recorded leaf shape category and measured leaf surface area, node number, chlorophyll content, nitrogen content, and photosynthesis in four trees