Transmission of stony coral tissue loss disease (SCTLD) in simulated ballast water confirms the potential for ship-born spread.

Stony coral tissue loss disease (SCTLD) remains an unprecedented epizootic disease, representing a substantial threat to the persistence and health of coral reef ecosystems in the Tropical Western Atlantic since its first observation near Miami, Florida in 2014. In addition to transport between adjacent reefs indicative of waterborne pathogen(s) dispersing on ocean currents, it has spread throughout the Caribbean to geographically- and oceanographically-isolated reefs, in a manner suggestive of ship and ballast water transmission. Here we evaluate the potential for waterborne transmission of SCTLD including via simulated ballast water, and test the efficacy of commonly-used UV radiation treatment of ballast water. Two species of reef-building corals (Orbicella faveolata and Pseudodiploria strigosa) were subjected to (1) disease-exposed or UV-treated disease-exposed water, and (2) a ballast hold time series of disease-exposed water in two carefully-controlled experiments to evaluate transmission. Our experiments demonstrated transmission of SCTLD through water, rather than direct contact between diseased and healthy corals. While UV treatment of disease-exposed water led to a 50% reduction in the number of corals exhibiting disease signs in both species, the statistical risk of transmission and volume of water needed to elicit SCTLD lesions remained similar to untreated disease-exposed water. The ballast hold time (24 h vs. 120 h) did not have a significant effect on the onset of visible disease signs for either species, though there appeared to be some evidence of a concentration effect for P. strigosa as lesions were only observed after the 120 h ballast hold time. Results from both experiments suggest that the SCTLD pathogens can persist in both untreated and UV-treated ballast water and remain pathogenic. Ballast water may indeed pose a threat to the continued spread and persistence of SCTLD, warranting further investigation of additional ballast water treatments and pathogen detection methods.

Rare Presentation of Pediatric Multiple Enchondromatosis Limited to Single Ray or Single Nerve Distribution in the Hand: A Multicenter Case Series.

BACKGROUND: Multiple enchondromas in the pediatric hand is a relatively rare occurrence and the literature regarding its incidence and treatment is sparse. Within this rare subset of patients, we identified a unique cohort in which lesions are confined to multiple bones in a single ray or adjacent rays within a single nerve distribution. We review the clinical and pathologic characteristics and describe the indications for and outcomes of treatment in this unique subset of patients as well as offer conjectures about its occurrence. METHODS: Institutional review board (IRB)-approved retrospective multicenter study between 2010 and 2018 identified subjects with isolated multiple enchondromas and minimum 2-year follow-up. Data analyzed included demographics, lesion quantification and localization, symptoms and/or fracture(s), treatment of lesion(s), complications, recurrence, and presence of malignant transformation. RESULTS: Ten patients were evaluated with average age at presentation of 9 years (range: 4 to 16) and mean clinical follow-up of 6 years (range: 2.8 to 8.6). Five subjects had multiple ray involvement in a single nerve distribution and 5 had single ray involvement with an average of 4 lesions noted per subject (range: 2 to 8). All children in the study had histopathologic-proven enchondromas and underwent operative curettage±bone grafting. Indications for surgical intervention included persistent pain, multiple prior pathologic fractures, impending fracture and deformity. During the study period three subjects experienced pathologic fracture treated successfully with immobilization. Recurrence was noted in 40% at an average of 105 weeks postoperatively (range: 24 to 260) and appears higher than that reported in the literature. No case of malignant transformation was observed during the study period. CONCLUSIONS: A rare subset of pediatric patients with multiple enchondromas of the hand is described with lesions limited to a single ray or single nerve distribution. Further awareness of this unique subset of patients may increase our understanding of the disease and improve patient outcomes. LEVEL OF EVIDENCE: Level IV-therapeutic (case series).

The Costs of Interfacility Transfers for Nonurgent Pediatric Supracondylar Fractures.

BACKGROUND: Unnecessary transfers of nonemergent pediatric musculoskeletal injuries to regional trauma centers can be costly. The severity of fracture displacement in supracondylar humerus fractures dictates the risk of complications, the urgency of transfer and the need for surgical treatment. The purpose of this study is to examine the transfer patterns of Gartland type II pediatric supracondylar humerus fractures to identify strategies for improving patient care, improving health care system efficiency, and reducing costs. We hypothesize that there will be a high rate of unnecessary, emergent transfers resulting in increased cost. METHODS: We retrospectively identified all pediatric patients that underwent treatment for a supracondylar humerus fracture between 2013 and 2018. Patient demographics, injury characteristics, chronological data, and surgical data were collected and analyzed from ambulance run sheets, transferring hospital records, and electronic medical records. Transfer distances were estimated using Google-Maps, while transfer costs were estimated using Internal Revenue Service (IRS) standard mileage rates and the American Ambulance Association Medicare Rate Calculator. A student t test was used to evaluate different treatment groups. RESULTS: Sixty-two patients had available and complete transfer data, of which 44 (71%) patients were safely transferred via private vehicle an average distance of 51.8 miles, and 18 (29%) patients were transferred via ambulance on an average distance of 55.6 miles ( P =0.76). The average transfer time was 4.1 hours by private vehicle, compared with 3.9 hours by ambulance ( P =0.56). The average estimated cost of transportation was $28.23 by private vehicle, compared with $647.83 by ambulance ( P =0.0001). On average, it took 16.1 hours after injury to undergo surgery and 25.7 hours to be discharged from the hospital, without a significant difference in either of these times between groups. There were no preoperative or postoperative neurovascular deficits. CONCLUSION: Patients with isolated Gartland type II supracondylar humerus fractures that are transferred emergently via ambulance are subjected to a significantly greater financial burden with no demonstrable improvement in the quality of their care, since prior research has shown these injuries can safely be treated on an outpatient basis. Potential options to help limit costs could include greater provider education, telemedicine and improved coordination of care. LEVEL OF EVIDENCE: Level III (retrospective comparative study).

What is the minimum torque required to obtain passive elbow end range of motion?

BACKGROUND: Passive range of motion is a common clinical assessment. The point at which passive end range of motion is measured is typically described by the 'end-feel'of the joint. RESEARCH QUESTION: What is the minimum amount of torque required to obtain passive elbow flexion and extension in children? METHODS: Twenty-five children (age, 7.5 ± 1.6 years-old), who had previously sustained unilateral distal humeral fractures, participated in this prospective study.Passive elbow flexion and extension was measured at least 8 weeks and up to one year out of cast. Motion capture cameras were used to track twenty-one reflective markers placed on subjects and two markers attached to the pad of a force transducer.Five trials of passive range of motion (flexion and extension) were performed on both arms. Elbow joint moments were calculated as products of the forces applied and lengths to the elbow centers. A one way ANOVA was used to determine differences in moments for flexion and extension for both involved and uninvolved limbs. Pairedsamples t-tests were used to determine differences between the involved and the uninvolved limbs for both maximum flexion and extension. RESULTS: There was no difference in the minimum mean joint moment (2.7 ± 1.1 Nm) at end range of motion. However, differences in passive range of motion was found between involved and uninvolved elbows (flexion p < .001; extension p = .001). SIGNIFICANCE: The results demonstrate therapists obtained end range of passive elbow flexion and extension applying the same amount of minimum torque. A small torque is sufficient to achieve end range of elbow motion for children. This torque can be used in guiding clinical practice for assessing passive range of elbow motion in pediatric population. Because of a paucity of data for any joint, future research developing force data for other joints should be conducted.

Evaluating Perioperative Complications Surrounding Supracondylar Humerus Fractures: Expanding Indications for Outpatient Surgery.

BACKGROUND: Supracondylar humerus (SCH) fractures are one of the most common pediatric orthopaedic injuries. Described using the Wilkins modification of the Gartland Classification system, current practice guidelines give moderate evidence for closed reduction and percutaneous pinning of type 2 and 3 injuries, but little evidence exists regarding the appropriate surgical setting for fixation. The goal of this study was to evaluate the perioperative complication profile of type 3 fractures with maintained metaphyseal contact and determine their suitability for outpatient surgery. METHODS: Skeletally immature patients with type 2 and 3 SCH fractures treated at a single, Level-1 trauma institution from March 2019 to January 2000 were retrospectively reviewed. A total of 1126 subjects were identified. Open, concomitant injuries, incomplete physical examination, initial neurovascular compromise, flexion-type fractures, ecchymosis, skin compromise, and those managed nonoperatively were excluded. Type 3 fractures were categorized as either "3M" versus type "3" ("M" denoting metaphyseal bony contact). Demographic data, neurovascular changes, and postoperative complications were collected. Categorical variables were evaluated using χ2 or Fisher exact tests, and continuous variables analyzed using analysis of variance, with significance defined as a P-value <0.05. RESULTS: A total of 485 patients (189 type 2, 164 type 3M, 132 type 3) met inclusion criteria. Sex and length of stay did not differ among groups. The incidence of neurovascular change between initial presentation and surgical fixation was significantly greater for type 3 fractures compared with other groups (P=0.02). No child in the 3M group had preoperative neurovascular examination changes, compared with 3 patients with type 3 injuries. When directly compared with the 3M group, type 3 fractures had a higher incidence of neurovascular examination changes that trended towards significance (P=0.08). There was no difference in postoperative complication rate between groups (P=0.61). CONCLUSIONS: Our findings demonstrate that Gartland type 3 SCH fractures lacking metaphyseal bony contact, compared with types 3M and 2, are more likely to experience neurovascular examination changes between initial presentation and definitive surgical fixation. Type 3M fractures clinically behaved like type 2 injuries and, accordingly, could be considered for treatment on an outpatient basis. LEVEL OF EVIDENCE: Level III-retrospective comparative study.

Assessment of Lateral Rotation Percentage and Rotational Deformity of the Elbow in Type 3 Supracondylar Humerus Fractures: A Biomechanical Study.

BACKGROUND: Supracondylar humerus (SCH) fractures are the most common elbow fractures in children. Historically, displaced (Gartland type 3) SCH fractures have been treated with closed reduction and percutaneous pinning. Fluoroscopic imaging is used intraoperatively in order to assess adequate reduction of the fracture fragments before pinning. On lateral fluoroscopic and radiographic images, a lateral rotation percentage (LRP) can be estimated in order to assess rotational deformity. The purpose of this study was to determine the true rotational deformity of distal humerus fracture fragments in SCH fractures based upon the LRP using a clinically relevant laterally based pinning technique. METHODS: In this study, a sawbones model was used to examine the correlation between calculated LRP and the true degree of rotational deformity with 3 of the most common extension-type SCH fracture types (low transverse, high transverse, and lateral oblique). Because fracture stability was not the focus of this study, a single pin was used to hold the construct and allow for fragment rotation along a fixed axis. In this study, 2 of the authors independently measured rotational deformity and compared this with LRP on fluoroscopic lateral imaging of a sawbones model at 0 to 45 degrees of rotational deformity. RESULTS: The LRP of all 3 patterns demonstrated a near linear increase from 0 to 45 degrees with maximum LRP measured at 45 degrees for each of the 3 patterns. Univariate linear regression demonstrated an increase in LRP for the low transverse pattern of 2.02% for every degree of rotation deformity (R2=0.97), 2.29% for the lateral oblique pattern (R2=0.986), and 1.17% for the high transverse pattern (R2=0.971). Maximum LRP was measured at 45 degrees for all 3 patterns with a mean of 53.5% for the high transverse pattern, 93.5% for the low transverse pattern, and 111.2% for the lateral oblique pattern. A higher LRP was measured with increasing degrees of rotational displacement in the low transverse and lateral oblique patterns for all degrees of rotational deformity compared to the high transverse pattern. CONCLUSION: There is a near linear correlation between the degree of malrotation and the LRP with more superior metaphyseal fracture patterns demonstrating a lower LRP than inferior fracture patterns. CLINICAL RELEVANCE: Using our data one can estimate the degree of malrotation based on the LRP on radiographs in the clinical setting. LEVEL OF EVIDENCE: Not applicable (basic-science article).

Pulling the Trigger: Recommendations for Surgical Care of the Pediatric Trigger Thumb.

BACKGROUND: Despite being a common pediatric hand condition, there are few clear guidelines regarding the optimal management of pediatric trigger thumb. Our primary aim was to help guide surgical management of this disorder by establishing a treatment algorithm on the basis of our institution's experience. METHODS: This is an institutional review board-approved retrospective study of all patients with idiopathic trigger thumbs from 2005 to 2015 at a single institution. Demographics and treatment course were recorded for all patients including duration of follow-up, observation, surgical intervention, and complications. All children were classified according to the Sugimoto classification. RESULTS: A total of 149 patients with 193 thumbs met inclusion and exclusion criteria. 16.5% of patients had stage II thumbs, 10.3% of patients with stage III, and 73% of patients with stage IV thumbs. Of all patients with stage IV thumbs, 3.5% were locked in extension for an overall incidence of 2.6%.In total, 46% of patients failed observation and underwent surgical treatment. Only 14% of stage IV trigger thumbs resolved when observed, compared with 53% of stage II and 25% of stage III trigger thumbs. Stage IV thumbs were 4.6 times more likely to fail conservative treatment and go on to surgery than stage II or III thumbs (odds ratio, 4.6; P=0.006).Thirty-two percent of patients underwent surgery without an observation period. Older children with bilateral stage 3 thumbs were the most likely to go straight to the odds ratio instead of being observed (P=0.002, r=0.17).Of the total amount of patients who underwent surgery (116), there were 4 complications for a rate of 3.4% with a recurrence rate of 1.7%. CONCLUSIONS: On the basis of the data in this study, the authors would recommend that stage IV thumbs undergo surgery without an observational period. Second, stage II and stage III thumbs can be safely observed for at least 1 year before surgery. Finally, our study concurs with the literature that surgery can be successful with low rates of complications and recurrence. LEVEL OF EVIDENCE: Level IV.

Pediatric Ganglion Cyst Recurrence: Location Isn't the Only Risk Factor.

INTRODUCTION: Ganglion cysts represent the most common benign soft-tissue masses of the hand and wrist, most are treated nonoperatively, with relatively few local recurrences. Few studies have identified risk factors for recurrence in the pediatric population. The aim of this study is to identify risks of cyst recurrence and to establish if ultrasonographic imaging aids in the prediction of recurrence. METHODS: A single-center retrospective chart review was performed, identifying patients diagnosed with a ganglion cyst of the hand or wrist. Demographic information, cyst characteristics, and ultrasound examination reports were documented. Standard statistical and logistic regression analyses were performed. RESULTS: A total of 132 cysts were identified in 126 patients and the average age was 8.5 years old. The most common location was the dorsal wrist (57/132, 43.2%). There were 14 recurrences [11/14, (79%) dorsal wrist, 3/14 (21%) volar wrist, 0/14 (0%) in nonwrist locations]. The risk of recurrence was significantly greater for dorsal wrist cysts than nonwrist locations (odds ratio=18.1; 95% confidence interval: 1.02, 316.65; P=0.048); there was no statistical difference in recurrence rates between dorsal and volar cysts (P=0.15). Recurrence was noted in older patients (12.2 vs. 8.1 y, P<0.001) and those patients with painful masses (P=0.02). Patients undergoing surgical excision had a higher risk of recurrence than those who did not undergo surgical excision (P<0.001). Cyst volume as measured by ultrasound was performed in 37 cysts, with repeat ultrasounds in 12 cases demonstrating a decreased volume of 0.85 cm at baseline to 0.35 cm with repeat examination (P=0.40). In patients that received at least 1 ultrasound, there were no differences in cyst volume between those that recurred and those that did not (P=0.40). CONCLUSIONS: Risk factors for recurrence in pediatric patients with a ganglion cyst include older age, symptomatic masses, cysts located around the wrist, and those requiring surgical excision. Ultrasound examination of cyst volume did not predict recurrence. LEVEL OF EVIDENCE: Level III-therapeutic.

A Salter-Harris II Distal Radius Fracture Irreducible by Closed Methods.

CASE: A 10-year-old boy presented with a Salter-Harris II distal radius fracture that was irreducible by closed methods. An open reduction was performed in the operating room where a sleeve of periosteum was found interposed between the fracture fragments. Successful reduction was performed without difficulty after the periosteum was removed from the fracture. CONCLUSION: Soft-tissue interposition must be kept in mind when having difficulty performing closed reductions of pediatric distal radius physeal fractures to avoid excessive reduction attempts.

Upper extremity anomalies in children with femoral and fibular deficiency.

Defects occurring in the femoral-fibular-ulnar developmental field are believed to cause the cluster of anomalies seen with femoral, fibular and ulnar limb deficiencies. Upper limb function must be considered in the management of lower limb deficiencies. The purpose of this study is to determine the frequency and type of upper extremity anomalies found in children with femoral and/or fibular deficiency. A retrospective review of 327 consecutive patients with the diagnosis of femoral and/or fibular deficiency was performed using existing records and radiographs. Characteristics of those with and without upper extremity anomalies were compared. Upper extremity anomalies were identified in 56 patients. They were more common among those with bilateral, compared with unilateral, lower extremity deficiencies (P < 0.0001). Seventy-five upper limbs were involved with 50 ulnar deficiencies, nine congenital transhumeral deficiencies, four congenital shoulder disarticulations, seven cleft hands, two radial head dislocations and one each - radial deficiency, syndactyly and capitate-lunate coalition. Two patients with bilateral upper extremity anomalies had ulnar deficiency on one side and a transverse deficiency on the other. Upper extremity anomalies are found in 17% of children with femoral and/or fibular deficiency, especially with bilateral lower extremity involvement. Ulnar deficiency is the most common type but one-third had other anomalies. The frequent finding of congenital transverse upper extremity deficiencies suggests there may be common embryology.

Bioprospecting solid binding polypeptides for lithium ion battery cathode materials.

Biotemplating presents a promising approach to improve the performance of inorganic materials via specific control over morphology, crystal structure, and the size of particles during synthesis and assembly. Among other biotemplates, solid binding polypeptides (SBPs) isolated for the material of interest provide high binding affinity and selectivity due to distinct combinations of functional groups found in amino acids. Nanomaterials assembled and synthesized with SBPs have found widespread applications from drug delivery to catalysis and energy storage due to their improved properties. In this study, the authors describe the identification of SBPs for binding to Li-ion battery cathode materials LiCoPO4, LiMn1.5Ni0.5O4, and LiMn2O4, which all have potential for improvement toward their theoretical values. The binding affinity of isolated peptides was assessed via phage binding assays and confirmed with electron microscopy in order to select for potential biotemplates. The authors demonstrate ten binding peptides for each material and analyze the sequences for enrichment in specific amino acids toward each structure (olivine and spinel oxide), as well as the test for specificity of selected sequences. In further studies, the authors believe that the isolated SBPs will serve as a template for synthesis and aid in assembly of cathode materials resulting in improved electrochemical properties for Li-ion batteries.

Severity of ulnar deficiency and its relationship with lower extremity deficiencies.

To assess the characteristics of ulnar deficiency (UD) and their relationship to lower extremity deficiencies, we retrospectively classified 82 limbs with UD in 62 patients, 55% of whom had femoral, fibular, or combined deficiencies. In general, UD severity classification at one level (elbow, ulna, fingers, thumb/first web space) statistically correlated with similar severity at another. Ours is the first study to show that presence of a lower limb deficiency is associated with less severe UD on the basis of elbow, ulnar, and thumb/first web parameters. This is consistent with the embryological timing of proximal upper extremities developing before the lower extremities.

Radiologic Evaluation of the Distal Radius Indices in Early And Late Childhood.

The osseous anatomy of the distal radius is well documented in adults. Three commonly discussed variables are the volar tilt (also known as palmar tilt or palmar inclination), radial inclination, and radial height. These values are not well defined in the growing skeleton. We studied the radiographic measurements of normal distal radius osseous anatomy in children and identified how these values change with age. 372 patients (215 males and 157 females) between the ages of 8 and 16 were included in the study. Normal values of volar tilt, radial inclination, and radial epiphyseal height were defined for each age group. Regression analysis showed that volar tilt increased significantly by increase in age (P <0.001). Radial inclination and radial epiphyseal height both showed significant increase with increase in age (P<0.001). This is the first study to define these radiographic values in children and their change with age.

Radial Polydactyly and the Incidence of Reoperation Using A New Classification System.

BACKGROUND: Polydactyly is one of the more common congenital deformities with an incidence of 0.8 to 1.4 per 1000. Traditionally the Wassel Classification system has been used, which is based on the level of duplication seen on plain radiographs. Although it is helpful in describing the anatomic characteristics, it is somewhat limited with regards to surgical planning and postoperative outcomes. Chung and colleagues, recently proposed a new classification system that categorizes radial polydactyly based on morphologic features that provides helpful information to be used in surgical decision making. We reviewed all radial polydactyly cases that had undergone operative intervention at our center over a 10-year period to investigate if this new classification system correlates with the rate of reoperation. METHODS: A total of 60 thumbs in 54 patients that were treated surgically from 2000 to 2010 at our institution were included in this study. Only patients with a minimum follow-up of 2 years were included. The authors categorized all duplications based on the classification system proposed by Chung and colleagues: type I (Joint Type), type II (Single Epiphyseal Type), type III (Osteochondroma-like Type), and type IV (Hypoplastic Type). Statistical analysis was then used to look at this classification system as it relates to sex, family history, syndrome association, and the need for reoperation. RESULTS: Of the 60 radial polydactyly cases, 37 (62%) were type I; 6 (10%) were type II; 6 (10%) were type III; and 11 (18%) were type IV. Six thumbs underwent reoperation for residual deformity-3 type I, 3 type II, and none of the types III or IV. No statistical significance was found when comparing classification group to sex, family history, syndrome association, laterality, or bilateral involvement. Statistical significance (P<0.05) was found between groups and the need for reoperation. CONCLUSIONS: The new classification system proposed by Chung and colleagues is easy to use and can guide practitioners in their discussions with patients regarding surgical outcomes and possible need for revision surgery.

Sample port design for ballast water sampling: Refinement of guidance regarding the isokinetic diameter.

By using an appropriate in-line sampling system, it is possible to obtain representative samples of ballast water from the main ballast line. An important parameter of the sampling port is its "isokinetic diameter" (DISO), which is the diameter calculated to determine the velocity of water in the sample port relative to the velocity of the water in the main ballast line. The guidance in the U.S. Environmental Technology Verification (ETV) program protocol suggests increasing the diameter from 1.0× DISO (in which velocity in the sample port is equivalent to velocity in the main line) to 1.5-2.0× DISO. In this manner, flow velocity is slowed-and mortality of organisms is theoretically minimized-as water enters the sample port. This report describes field and laboratory trials, as well as computational fluid dynamics modeling, to refine this guidance. From this work, a DISO of 1.0-2.0× (smaller diameter sample ports) is recommended.

3D imaging provides a high-resolution, volumetric approach for analyzing biofouling.

A volumetric approach for determining the fouling burden on surfaces is presented, consisting of a 3D camera imaging system with fine (5 µm) resolution. Panels immersed in an estuary on the southwest coast of Florida, USA were imaged and the data were used to quantify seasonal changes in the biofouling community. Test panels, which were submerged in seawater for up to one year, were analyzed before and after gentle scrubbing to quantify the biovolume of the total fouling community (ie soft and hard organisms) and the hard fouling community. Total biofouling ranged from 0.01 to 1.16 cm(3) cm(-2) throughout the immersion period; soft fouling constituted 22-87% of the total biovolume. In the future, this approach may be used to inform numerical models of fluid-surface interfaces and to evaluate, with high resolution, the morphology of fouling organisms in response to antifouling technologies.

Validation trials of a shipboard filter skid (p3SFS) demonstrate its utility for collecting living zooplankton.

Relatively large volumes of water-on the order of cubic meters-must be sampled and analyzed to generate statistically valid estimates of sparsely concentrated organisms, such as in treated ballast water. To this end, a third prototype of a shipboard filter skid (p3SFS) was designed and constructed. It consisted of two housings (each containing a 35 µm mesh filter bag) and its own pump and computer controller. Additionally, the skid had a drip sampler, which collected a small volume (∼ 10 L) of whole (unfiltered) water immediately upstream of the housings. Validation of the p3SFS occurred in two segments: (1) land-based trials, in which the collection of organisms ⩾ 50 µm (nominally zooplankton) by the p3SFS was compared to a plankton net, and (2) shipboard trials, in which ballast water was sampled aboard a ship. In both types of trials, the data collected showed the filter skid to be an appropriate flow-through sampling device.

Stratification of living organisms in ballast tanks: how do organism concentrations vary as ballast water is discharged?

Vertical migrations of living organisms and settling of particle-attached organisms lead to uneven distributions of biota at different depths in the water column. In ballast tanks, heterogeneity could lead to different population estimates depending on the portion of the discharge sampled. For example, concentrations of organisms exceeding a discharge standard may not be detected if sampling occurs during periods of the discharge when concentrations are low. To determine the degree of stratification, water from ballast tanks was sampled at two experimental facilities as the tanks were drained after water was held for 1 or 5 days. Living organisms ≥50 µm were counted in discrete segments of the drain (e.g., the first 20 min of the drain operation, the second 20 min interval, etc.), thus representing different strata in the tank. In 1 and 5 day trials at both facilities, concentrations of organisms varied among drain segments, and the patterns of stratification varied among replicate trials. From numerical simulations, the optimal sampling strategy for stratified tanks is to collect multiple time-integrated samples spaced relatively evenly throughout the discharge event.

Thumb hypoplasia.

Hypoplasia of the thumb refers to a spectrum of clinical abnormalities ranging from a slightly small digit to complete absence (or aplasia) of the thumb unit. As a component of radial dysplasia, thumb hypoplasia can be either an isolated entity or seen in conjunction with other elements of radial longitudinal deficiency. Treatment of this condition initially involves identifying and addressing co-morbid anomalies in other body systems. The severity of thumb hypoplasia is then graded so that appropriate treatment methods can be instituted. The goal of treatment is ultimately to provide the child with a stable and functional thumb unit.

Capture and manipulation of magnetically aligned Pf1 with an aqueous polymer gel.

The magnetic alignment of the Pseudomonas bacteriophage Pf1 is captured indefinitely in a gel of the aqueous triblock copolymer Pluronic F-127. In addition to preserving high-resolution liquids NMR spectra for dissolved solutes, the gel prevents the reorientation of the phage allowing mechanical manipulation of the angle between the axis of the phage alignment and the static magnetic field. The residual 2H quadrupolar couplings for several solutes dissolved in this material as a function of the angle Theta between the non-spinning sample tube and the static magnetic field are consistent with the value of P(2)(cosTheta)=(3cos(2)Theta-1)/2. The variable-angle correlation spectrum for these solutes is shown to separate residual quadrupolar effects from isotropic chemical shifts. Finally, the compatibility of Pluronic F-127 with NMR studies of aqueous biological macromolecules is demonstrated in a measurement of residual dipolar couplings in an 15N-labeled nucleic acid.