Search

Abstract Ecosystem‐based forest management requires long planning horizons to incorporate forest dynamics — changes resulting from vegetation growth and succession and the periodic resetting of these by natural and anthropogenic disturbances such as fire, wind, insects, and timber harvests. Given these dynamics, ecosystem‐based forest management plans should specify desired conditions such as tree species composition, age class, tree density and structure, size and density of snags and course woody debris, and the size, shape, and juxtaposition of trees, groups of trees, and stands in order to create and sustain habitats for wildlife. The management recommendations for the northern goshawk (Accipiter gentilis) in the southwestern United States (hereafter, recommendations; Reynolds et al. 1992) is a management plan designed to conserve this top predator by accounting for factors thought to limit their populations: vegetation structures, foods, predators, and competitors. The recommendations combined coarse‐ and fine‐filter approaches to develop desired habitats for goshawks and their prey in landscapes whose compositions, structures, and patterns were conditioned on the aut‐ and synecologies of over‐ and understory plant species in forest ecosystems. Management plans that address all stages of a species' life history, the physical and biological factors limiting its populations, the habitats of other members of its ecological community, and the spatial and temporal dynamics of forests it occupies should be robust to failure (Reynolds et al. 2006a, b). The recommendations have been implemented in National Forests in the southwestern United States since 1996 (USDA Forest Service 1996), but their efficacy at conserving goshawk reproduction and survival has yet to be demonstrated. Recently, Beier et al. (2008) conducted a test of the recommendations and concluded that reproduction of goshawks declined as forest structures in their breeding areas became increasingly similar to those described in the recommendations. Here we show that methods they used to determine similarity to the structural conditions described in the recommendations resulted in inappropriate measures of similarity. We also show that their monitoring of goshawk reproduction on the 13 breeding areas used in their study was insufficient, and show how their insufficient monitoring introduced a systematic bias that reduced the precision of their test even if they had correctly measured similarity. We end by suggesting approaches for determining structural similarity to the goshawk recommendations in ponderosa pine and how to achieve adequate sampling for reproduction on breeding areas. © 2012 The Wildlife Society.

We responded to the claim by Greenwald et al. (2005) that the management recommendations for the northern goshawk in the Southwestern United States (MRNG; Reynolds et al. 1992), a food web-based conservation plan that incorporated both northern goshawk (Accipiter gentilis) and multiple prey habitats, may be inadequate to protect goshawks. Greenwald et al. (2005) based this claim on their review of 12 telemetry studies of goshawk habitat selection and 5 nontelemetry studies of the effects of vegetation structure at the home range scale on goshawk nest occupancy and reproduction that appeared after the 1992 publication of the MRNG. Greenwald et al. (2005) summarized their review as showing that 1) goshawks were habitat specialists limited to forests with mature and old-growth structures including large trees, high canopy cover, multiple canopy layering, and abundant woody debris; 2) habitats were not selected on the basis of prey abundance and, therefore, managing for prey habitats diluted goshawk habitats; and 3) selection for openings, edges, and habitat diversity was inconclusive. Our review found that when the studies' respective authors pooled their radiotagged goshawks there were weak to strong selections for old forest structures. However, the studies also documented extensive variation in use of vegetation types and structures by individual goshawks; some avoided openings, edges, young forests, and old forests, whereas others selected for these characteristics. Additionally, by virtue of their wide geographic distribution, the studies showed that the focal populations themselves occurred in a variety of forest types, some with large structural differences. We found no evidence in Greenwald's et al. (2005) review that the MRNG are inadequate to protect goshawks. Rather, the studies reviewed by Greenwald et al. (2005), as well as many studies they missed, supported the MRNG. The suggestion of inadequacy by Greenwald et al. (2005) appeared rooted in misunderstandings of goshawk habitats described in the MRNG, a discounting of the extent of variation in vegetation structural and seral stages used by goshawks, a limited understanding of the extent to which prey limits goshawks, a failure to recognize the dynamic nature of forests, and an incomplete review of the literature. We believe the MRNG are adequate because they maximize the sustainable amount of mature and old forests in goshawk home ranges and specify the kinds and intermixtures of prey habitats within home ranges. Implementation of MRNG should reduce the likelihood that the availability of vegetation structures suited to goshawk nesting and foraging, as well as abundance and availability of prey, will limit goshawk nest occupancy and reproduction. [ABSTRACT FROM AUTHOR]

Botox injection and pneumatic dilation are common therapies for achalasia. We sought to determine the impact of these preoperative therapies on esophageal muscle histology and outcomes after laparoscopic Heller myotomy. A total of 73 consecutive patients had esophageal muscle biopsies taken from the gastroesophageal junction at the time of myotomy between November 1998 and November 2001. Muscle fibrosis was graded by a senior pathologist who was blinded to preoperative treatments and postoperative outcomes. Patients graded their dysphagia and heartburn symptoms before and after myotomy and graded their outcomes at follow-up. Patients were grouped according to the preoperative endoscopic treatment (dilation, Botox, both, or neither) and the groups were compared. Preoperative therapy did not correlate with esophageal fibrosis or postoperative outcomes, and the degree of esophageal muscle fibrosis was not predictive of outcome. Symptom scores improved significantly for dysphagia (4.5 ± 0.9 vs. 1.6 ± 1.6) and heartburn (2.3 ± 1.8 vs. 1.5 ± 1.4) irrespective of preoperative therapy or fibrosis. Overall, excellent or good outcomes were obtained in 92% of patients at follow-up of 15.7 months ± 14.4. Successful outcomes are highly probable after laparoscopic Heller myotomy regardless of preoperative interventions. The amount of fibrosis in the esophageal muscle is not related to preoperative intervention and is not predictive of outcomes. (J Gastrointest Surg 2003;7:181–190.) [Copyright &y& Elsevier]

This study was performed to develop a system to measure dysphagia in an objective fashion, test its correlation with subjective estimates of dysphagia, and encourage the use of a standardized measure of esophageal stenosis. Thirty-five patients with mechanical dysphagia underwent subjective estimates of dysphagia using a dysphagia scale graded from 0 to 5, as well as a diet scale. Lumen diameter was measured endoscopically, using the open or dosed biopsy forceps as a measuring guide. Patients were then given barium capsules or tablets of increasing diameter under fluoroscopy, in the upright position. Pills were given sequentially until a pill failed to traverse the esophagus in less than 20 s. The diameter of the pill failing to traverse the esophagus within 20 s correlated strongly with the endoscopically measured diameter by Spearmans rank correlation (Rs = 0.85). The weakest correlation was between endoscopically measured diameter and the dysphagia scale (Rs = 0.48). The diameter of the pill failing to traverse the esophagus within 20 s is an excellent estimate of esophageal lumen diameter. Pill size correlates much better with esophageal lumen diameter than dysphagia or diet scales. This new dysphagia assessment system should simplify standardization of the grading of dysphagia. [ABSTRACT FROM AUTHOR]

Two multi-investigator, double-blind, randomized, placebo-controlled, crossover trials were conducted to determine whether tri-buffered formulations of both regular strength aspirin and extra strength aspirin would be less likely than plain aspirin to provoke subjective gastrointestinal (GI) intolerance. Each trial was divided into two phases, a qualification phase and a test phase. During the qualification phase, subjects with a history of gastrointestinal intolerance to aspirin were randomized to a double-blind crossover treatment with aspirin and placebo (325 mg aspirin per tablet in study 1 and 500 mg aspirin per tablet in study 2), two tablets four times a day for 3 days or until the occurrence of stomach upset. Subjects who reported gastrointestinal symptoms with aspirin and not with placebo qualified to participate in the test phase of the study. They were rerandomized to participate in a three-way crossover study of plain aspirin, tri-buffered aspirin, and placebo in the test phase. Tri-buffered aspirin was associated with an appreciable reduction in the incidence of gastrointestinal upset relative to plain aspirin, 34 percentage points in study 1 (p < 0.001) and 33 percentage points in study 1 (p < 0.001). Similar results were obtained in the evaluation of the reduction of the severity of gastrointestinal symptoms. [ABSTRACT FROM AUTHOR]

Many authors have objected to the use of esophageal stents in the palliative management of lesions obstructing the cervical esophagus, especially when the prosthesis must lie within 2 cm of the cricopharyngeus muscle (CPM). Ten patients with stenosis of the cervical esophagus by lesions within 2 cm of or involving the CPM were considered for prosthesis placement. The prosthesis was successfully placed in eight patients, five of whom had a tracheoesophageal fistula (TEF). A prosthesis could not be placed in two patients, and two patients complained of a minimal but tolerable foreign body sensation. Six prostheses were custom-made. The necessity to place a prosthesis within 2 cm of or even immediately proximal to the CPM should not be considered an absolute contraindication to esophageal prosthesis placement in selected patients. Foreign body sensation may be absent or minimal, and stent migration is common. [ABSTRACT FROM AUTHOR]

Analyzes cases of peritoneoscopy. Purpose in undertaking the procedure; Age and number of patients that participated; Distribution of diagnosis or main findings upon completion of peritoneoscopy.

Evaluates the palliative dilation for dysphagia in esophageal carcinoma. Information on the patients; Materials and methods; Results of the study.

Comments on a method of placing a guide wire beyond an esophageal stricture to ensure proper passage of a dilator through complex or severely stenotic strictures. Remarks on the safety of wire passage through the endoscope from a point proximal to the stricture; Cost of the procedure; Ways to ensure accurate wire position.

High-power, relativistic electron beams from energy-recovering linacs have great potential to realize new experimental paradigms for pioneering innovation in fundamental and applied research. A major design consideration for this new generation of experimental capabilities is the understanding of the halo associated with these bright, intense beams. In this Letter, we report on measurements performed using the 100 MeV, 430 kW cw electron beam from the energy-recovering linac at the Jefferson Laboratory's Free Electron Laser facility as it traversed a set of small apertures in a 127 mm long aluminum block. Thermal measurements of the block together with neutron measurements near the beam-target interaction point yielded a consistent understanding of the beam losses. These were determined to be 3 ppm through a 2 mm diameter aperture and were maintained during a 7 h continuous run.

The purpose of this study was to examine the impact of surgical pathology, anesthesiologist experience, and airway technique on surgically relevant outcomes in patients identified by preoperative laryngoscopy to have a difficult airway due to head and neck pathology. We prospectively recorded a series of 152 difficult airway cases due to head and neck pathology out of 2,145 direct laryngoscopies undertaken between November 2005 and June 2008. One of two senior anesthesiologists specializing in head and neck procedures intubated 101 (66.4%) of the 152 patients and did so 3.3 minutes faster (p = 0.51), with better oxygenation (87.3 vs. 81.8%; p = 0.02) and fewer airway plan changes (p = 0.001) than did other, nonspecialist anesthesiologists. Predictors of failure of the first intubation plan included: cancer diagnosis (p = 0.02), previous radiotherapy (p = 0.03), and supraglottic lesions (p = 0.03). Glottic/subglottic lesions required the most intubation attempts (p = 0.02). Awake fiberoptic intubation was the most common method used (44.7%) but resulted in a change in the airway plan in 6 cases (8.8%). Gas induction maintained the best oxygenation (p = 0.01). Awake tracheostomy was infrequent (1.3%) and took the longest (p = 0.006). We concluded that difficult airways due to head and neck pathology require teamwork and a backup plan. An anesthesiologist specializing in head and neck procedures may help to avoid adverse outcomes associated with cancer, especially previously irradiated supraglottic/glottic lesions, leading to a less frequent need for awake tracheostomy.

We present a search at the Jefferson Laboratory for new forces mediated by sub-GeV vector bosons with weak coupling α' to electrons. Such a particle A' can be produced in electron-nucleus fixed-target scattering and then decay to an e + e- pair, producing a narrow resonance in the QED trident spectrum. Using APEX test run data, we searched in the mass range 175-250 MeV, found no evidence for an A'→ e+ e- reaction, and set an upper limit of α'/α ~/= 10(-6). Our findings demonstrate that fixed-target searches can explore a new, wide, and important range of masses and couplings for sub-GeV forces.

We show that the P2Y(6) receptor, a purinergic G protein-coupled receptor with a high affinity for the nucleotide uridine diphosphate, is an important endogenous inhibitor of T cell function in allergic pulmonary inflammation. Mice conditionally deficient in P2Y(6) receptors [p2ry6 (flox/flox);cre/+ mice] exhibited severe airway and tissue pathology relative to P2Y(6)-sufficient [p2ry6 (flox/flox)] littermates (+/+ mice) when treated intranasally with an extract of the dust mite Dermatophagoides farinae (Df). P2Y(6) receptors were inducibly expressed by lung, lymph node, and splenic CD4(+) and CD8(+) T cells of Df-treated +/+ mice. Df-restimulated P2Y(6)-deficient lymph node cells produced higher levels of Th1 and Th2 cytokines, and polyclonally stimulated P2Y(6)-deficient CD4(+) T cells proliferated faster than comparably stimulated P2Y(6)-sufficient cells. The absence of P2Y(6) receptors on CD4(+) cells, but not APCs, was sufficient to amplify cytokine generation. Thus, P2Y(6) receptors protect the lung against exuberant allergen-induced pulmonary inflammation by inhibiting the activation of effector T cells.

The National Board of Veterinary Medical Examiners was interested in the possible effects of word count on the outcomes of the North American Veterinary Licensing Examination. In this study, the authors investigated the effects of increasing word count on the pacing of examinees during each section of the examination and on the performance of examinees on the items. Specifically, the authors analyzed the effect of item word count on the average time spent on each item within a section of the examination, the average number of items omitted at the end of a section, and the average difficulty of items as a function of presentation order. The average word count per item increased from 2001 to 2008. As expected, there was a relationship between word count and time spent on the item. No significant relationship was found between word count and item difficulty, and an analysis of omitted items and pacing patterns showed no indication of overall pacing problems.

Purpose: Our objective was to demonstrate that preemptive vessel dilator cricothyrotomy may be useful when managing the patient with airway obstruction., Methods: An Institutional Review Board approved retrospective study was undertaken in 88 patients for whom this technique was selected. The anesthesiologists and surgeons identified as authors were directly involved in the care of these patients. All vessel dilator cricothyrotomies were performed in the operating rooms of University Hospital, UAB, Medical Center. The patients selected for this airway management technique were afflicted with some type of supraglottic lesion, usually squamous cell carcinoma, which was obstructing their airways to an extent that complete airway obstruction during induction of anesthesia was a significant possibility. Prior to induction of anesthesia, the vessel dilator was inserted into the tracheal lumen through the cricothyroid membrane as described. Oxygenation was maintained with jet ventilation from a Sanders jetting device. Age, sex, weight, initial and lowest O(2) saturation, first recorded ETCO(2), blood pressure and duration of jet ventilation were recorded., Results: The airways were successfully managed in all 88 patients with this technique. There were no deaths, and no postoperative hypoxic sequelae; also complications were minor., Conclusion: Vessel dilator cricothyrotomy as a preemptive procedure in the management of patients with significant supraglottic airway obstruction may be a useful addition to the anesthesiologists' armamentarium of airway management devices.

Individual molecules of multiarm starlike molecular brushes were visualized by atomic force microscopy. In the studied series of brushes, the number of arms varied from one for a linear chain to four, while the length of the side chains was kept approximately constant. Molecular visualization provided a unique opportunity for independent size characterization of the brush arms separately from that of the entire molecule. In agreement with the Schulz-Flory theory for chain coupling, the polydispersity of the total length was significantly lower than that of the arm length. The variation in polydispersity had an effect on molecular ordering. Lateral compression of the starlike brushes caused a transition from an extended dendritic-like conformation to a compact disklike conformation. In contrast to one-, two-, and three-arm brushes, the four-arm molecules with a lower polydispersity index of 1.04 demonstrated local hexagonal order.

Acute myelogenous leukemia (AML) is a hematologic disorder that is characterized by an abnormal proliferation of immature myeloid cells. Granulocytic sarcomas are clusters of leukemic myeloid cells that may develop as a result of AML. Oral manifestations of AML are common and often involve enlargements of the gingiva and/or mucosal tissue from direct leukemia cell infiltration. We describe the case history of a 50-year-old man who had an ulcerative lesion of the oral mucosa that was determined to be a granulocytic sarcoma of AML-MO subtype. The combination of both the subtype and clinical presentation of the leukemia makes this presentation unusual, and to the best of our knowledge, of a type that has not been previously reported in the literature.

Purpose: Fibreoptic intubation (FOI) has become an essential technique in the anesthetic management of patients with difficult airways. Unfortunately, residents may graduate from anesthesiology training programs with insufficient skills in FOI. To enhance resident proficiency at FOI without compromising patient comfort or safety, the technique of transnasal jet ventilation-assisted FOI was developed. This report describes our initial experience with this technique., Methods: Sixty-four patients scheduled for oromaxillofacial surgery under nasal endotracheal anesthesia were recruited. Twenty-eight residents at all levels of training performed FOI through the patient's right nostril after the induction of general anesthesia and neuromuscular blockade. Oxygenation and ventilation were maintained by a faculty anesthesiologist using a Sanders device to deliver a jet of oxygen through a nasal trumpet placed in the patient's left nostril. The time from induction until completion of the FOI was recorded. Residents were subsequently queried about the educational benefit of the technique using a standardized questionnaire., Results: All residents were able to successfully intubate all patients in this study. Thirteen residents successfully performed intubations on three or more occasions with 70% performing the technique faster on the third trial than on the first. No evidence of hypoxemia, gastric distension, pneumothorax, hemodynamic instability or recall was observed. All respondents to the questionnaire reported that the technique was useful as an educational tool and recommended its use with other residents., Conclusion: Transnasal jet ventilation-assisted FOI is a useful method to train residents in FOI while maximizing patient comfort and safety.

Background: Hypoxemia during the induction of general anesthesia for the morbidly obese patient is a major concern of anesthesiologists. The etiology of this pathophysiological problem is multifactorial, and patient positioning may be a contributing factor. The present study was designed to identify optimal patient positioning for the induction of general anesthesia that minimizes the risk of hypoxemia in these patients., Methods: 26 morbidly obese patients (body mass index-BMI 56 +/- 3) were randomly assigned to one of three positions for induction of anesthesia: 1) 30 degrees Reverse Trendelenburg; 2) Supine-Horizontal; 3) 30 degrees Back Up Fowler. Mask ventilation, full neuromuscular paralysis and direct laryngoscopy were performed. Any airway difficulties were noted. After endotracheal tube placement, subjects were ventilated for 5 minutes with 1% isoflurane in a mixture of 50% oxygen/50% air and then disconnected from the ventilation circuit. The time required for capillary oxygen saturation (SaO2), as measured by pulse oximeter, to decline from 100% to 92% was noted and identified as the safe apnea period (SAP). Ventilation was then immediately re-established. The lowest SaO2 after resuming ventilation and the time from that nadir to an SaO2 of 97% were also recorded., Results: BMI and hip-waist ratios of patients in groups 1, 2 and 3 did not significantly differ. There were no differences in airway difficulties between the different groups. The SAP in groups 1, 2 and 3 was 178 +/- 55, 123 +/- 24 and 153 +/- 63 seconds, respectively. The SaO2 of patients in the reverse Trendelenburg position dropped the least and took the shortest time to recover to 97%., Conclusions: In morbidly obese patients, the 30 degrees Reverse Trendelenburg position provided the longest SAP when compared to the 30 degrees Back Up Fowler and Horizontal-Supine positions. Since on induction of general anesthesia morbidly obese patients may be difficult to mask ventilate and/or intubate, this extra time may preclude adverse sequelae resulting from hypoxemia. Therefore, Reverse Trendelenburg is recommended as the optimal position for induction.

Unlabelled: This study evaluated the prevalence of upper respiratory symptoms (URS) among patients with symptomatic gastroesophageal reflux disease (GERD). Seventy-four subjects with heartburn completed a URS questionnaire before dual-probe, 24-h esophageal pH monitoring. The URS questionnaire was also completed by 74 normal volunteers without previous or current symptoms of GERD. Esophageal pH monitoring results were classified as normal, distal, or proximal and distal gastroesophageal reflux using standardized criteria. Mean URS scores (+/- SD) were 8.31 +/- 3.98 in the 52 subjects with GERD and 4.57 +/- 3.57 in the 22 subjects with negative pH probe studies, p = 0.02. Subjects with negative pH probe studies and normal volunteers scored similarly on the URS questionnaire. Reflux episodes/24 h correlated with URS scores, r = 0.47, p = 0.0001. Seventy-five percent of subjects with upper reflux, 68% of subjects with lower reflux, 36% of subjects with normal esophageal pH studies, and 9% of normal volunteers reported laryngeal symptoms for at least 5 d/mo. Sixty-nine percent of subjects with upper reflux, 50% of subjects with lower reflux, 31% of subjects with normal pH studies, and 14% of normal volunteers reported nasal symptoms for at least 5 d/mo. URS are frequent among subjects with GERD., Keywords: rhinitis; upper airway; gastroesophageal reflux