The state of systematics of North American Baetis Leach, 1815 (Ephemeroptera: Baetidae), with recommendations for identification of larvae.

The North American species of Baetis Leach (Ephemeroptera: Baetidae) are reviewed. Nearly one-third of species are either unknown or inadequately described in the larval stage, a fact not reflected in most keys or standard taxonomic efforts for bioassessment, which typically recommend species-level identifications of larvae. Furthermore, our new observations indicate that some previously published stage associations should be viewed as only tentative, and molecular evidence suggests that current species taxonomy does not reflect biological species. In order to acknowledge these deficiencies, but at the same time provide a degree of higher taxonomic resolution beyond the genus level, we recommend a scheme for identifications incorporating previously established species groups and the species complexes and species included within them. Species complexes are proposed for instances when there are either multiple species that cannot be differentiated in the larval stage or when multiple lines of evidence indicate more than one actual species is included in a single species concept. Complexes include B. flavistriga complex (B. flavistriga McDunnough + B. phoebus McDunnough + B. rusticans McDunnough), B. intercalaris complex (B. intercalaris McDunnough), B. vernus complex (B. brunneicolor McDunnough + B. vernus Curtis), B. bicaudatus complex (B. bicaudatus Dodds), B. tricaudatus complex (B. tricaudatus Dodds), and B. piscatoris complex (B. piscatoris Traver + B. palisadi Mayo + B. persecutus McDunnough [=B. persecutor McCafferty n. obj. syn]). A new larval identification key incorporating the B. piscatoris complex is provided.

Revision of the genus Caenota Mosely (Trichoptera: Calocidae), with descriptions of 2 new species and the larva of C. nemorosa Neboiss.

The caddisfly genus Caenota Mosely 1953 (in Mosely & Kimmins 1953) currently contains 5 species known from eastern Australia. Caenota is distinguished from other Calocidae genera by having adult males with greatly expanded maxillary palpi and a large membranous process associated with the antennal scape. Of the 5 described species, the larvae of only 1 is known. Here, we describe 2 new species, Caenota cudonis sp. nov. and C. equustagna sp. nov., from adult, larval, and pupal material. Also, we describe for the first time the larva of C. nemorosa Neboiss. These descriptions increase the number of Caenota species to 7 and the number of associated and described larvae to 4. This paper also provides descriptions of features associated with the adult head capsule of all described species of Caenota. Each of the known species is considered, with illustrations and re-descriptions of these features given.

A new species of Labiobaetis Novikova & Kluge, 1987 (Ephemeroptera: Baetidae) from Washington, USA.

Labiobaetis sonajuventus n.sp. is described from nymphs collected in a tributary of the Okanogan River in north-central Washington, USA. The new species is distinguished from North American congeners by the well-developed keel between the bases of the antennae, the concave lateral margin of labial palp segment 2, the apically expanded submarginal setae on the labrum, and its western Nearctic distribution.

Halophyte filter beds for treatment of saline wastewater from aquaculture.

The expansion of aquaculture and the recent development of more intensive land-based marine farms require efficient and cost-effective systems for treatment of highly nutrient-rich saline wastewater. Constructed wetlands with halophytic plants offer the potential for waste-stream treatment combined with production of valuable secondary plant crops. Pilot wetland filter beds, constructed in triplicate and planted with the saltmarsh plant Salicornia europaea, were evaluated over 88 days under commercial operating conditions on a marine fish and shrimp farm. Nitrogen waste was primarily in the form of dissolved inorganic nitrogen (TDIN) and was removed by 98.2 ± 2.2% under ambient loadings of 109-383 µmol l(-1). There was a linear relationship between TDIN uptake and loading over the range of inputs tested. At peak loadings of up to 8185 ± 590 µmol l(-1) (equivalent to 600 mmol N m(-2) d(-1)), the filter beds removed between 30 and 58% (250 mmol N m(-2) d(-1)) of influent TDIN. Influent dissolved inorganic phosphorus levels ranged from 34 to 90 µmol l(-1), with 36-89% reduction under routine operations. Dissolved organic nitrogen (DON) loadings were lower (11-144 µmol l(-1)), and between 23 and 69% of influent DON was removed during routine operation, with no significant removal of DON under high TDIN loading. Over the 88-day study, cumulative nitrogen removal was 1.28 mol m(-2), of which 1.09 mol m(-2) was retained in plant tissue, with plant uptake ranging from 2.4 to 27.0 mmol N g(-1) dry weight d(-1). The results demonstrate the effectiveness of N and P removal from wastewater from land-based intensive marine aquaculture farms by constructed wetlands planted with S. europaea.

A new species and new synonym in Heptagenia walsh (Ephemeroptera: Heptageniidae: Heptageniinae) based on molecular and morphological evidence.

A new mayfly species, Heptagenia whitingi Webb & McCafferty n.sp. is described from larvae, a male subimago, a female adult, and eggs collected from large rivers in the west-central portion of North America. Larvae are differentiated from other North American Heptagenia Walsh by a pair of large, rectangular pale markings on abdominal tergum 4, and the combination of having the posterior margin of the abdominal terga with bluntly pointed spines less than half the length of the fine setae, small blunt spines on the posterior margin of the caudal filaments, and numerous rows of setae laterally on the ventral surface of the labrum. A 630 bp partial sequence of the mitochondrial gene cytochrome oxidase 1 (COI) from three specimens of H. whitingi n.sp. was compared with those of 12 specimens representing eight other North American species of Heptagenia. Intraspecific sequence divergences based on Kimura-2-parameter (K2P) distance ranged from 0-1.1%. Interspecific sequence divergence based on K2P distance ranged from 8.9-20.0%. Heptagenia whitingi n.sp. differed from its sister taxon H. flavescens (Walsh) by 11.7%. Heptagenia diabasia Burks and H. elegantula (Eaton) differed from each other by only 1.1%; these two alleged species show a clinal pattern in larval abdominal coloration and there are no structural differences between the semaphorants. On this basis, H. diabasia is placed as a junior subjective synonym of H. elegantula, n.syn.

Revision of Heterocloeon McDunnough (Ephemeroptera: Baetidae).

The North American genus Heterocloeon McDunnough is redefined and shown to be distinct from other two-tailed Baetis complex genera, including Acentrella Bengtsson and Plauditus Lugo-Ortiz and McCafferty, which are also represented in North America. Heterocloeon is divided into three distinct subgenera, including Heterocloeon s.s., Iswaeon McCafferty and Webb, new subgenus, and Jubilatum McCafferty and Jacobus, new subgenus. Cladistic analysis supports the recognition of these subgenera within a genus defined by the presence of an apomorphic secondary ridge or denticle row on the larval claw; Heterocloeon s.s. and Jubilatum being sister groups, with their stem and Iswaeon branching basally within the Heterocloeon clade. The subgenus Heterocloeon, which possesses larval prothoracic osmobranchiae, retains the traditional species makeup of the genus. Iswaeon, which possesses a basally narrowed labial palp segment 2 and tibiae, and primary claw denticles of subequal length, includes a revalidated H. anoka (Daggy); H. davidi Waltz and McCafferty, new species; and H. rubrolaterale (McDunnough), new combination. Jubilatum, which posssesses an adenticulate secondary ridge on the claws and specialized tibial setation, includes H. amplum (Traver), new combination, and H. grande (Wiersema and Long), new combination. Previous confusion of H. anoka and Plaudituspunctiventris (McDunnough) is also resolved, with adult color patterns in Iswaeon and Plauditus shown to be of diagnostic importance.

Interface pressure produced by the traction post on a standard orthopaedic table.

Lower limb traction is applied with counter traction in the groin. The resultant tissue pressures can be high and may result in skin necrosis or nerve palsies. Volunteers were positioned on a fracture table and traction applied to the left leg. Perineal contact pressures were measured using pressure transducers connected to a laptop computer. Pressure readings and pain scores were recorded with different types of padding, whilst the leg was repositioned. Maximal pressures exceeded the 70 mmHg limit known to cause tissue damage. Larger (10 cm) padding devices significantly reduced the pressures. When employing the perineal traction post, care should be taken to pad this carefully to avoid the sequelae of high tissue pressure.

Quantified kinematics of the injury to the posterior cruciate ligament: a computer-aided design simulation study.

OBJECTIVE: To quantify the kinematics of the injury to the posterior cruciate and the other major knee ligaments as a function of the knee flexion angle at the moment of impact. DESIGN: Computer-aided design modelling was used to investigate the strain response of all major knee ligaments during antero-posterior abnormal tibio-femoral translation at 0-90 degrees knee flexion. BACKGROUND: It is generally believed that the likelihood of injury to the posterior cruciate ligament following anterior impact is higher in the flexed knee. However, there are no kinematical studies to quantify this clinical observation or investigate the role of the other knee ligaments in the above situation. METHODS: Computer calculations of the individual ligament strain were plotted against the magnitude of posterior tibial translation. Additionally, the strain rate for each ligament (defined as the ligament strain produced per mm of posterior tibial linear translation) was calculated as the slope of the strain-displacement curve for all tested degrees of knee flexion. RESULTS: The posterior cruciate ligament has been shown to be the primary restraint to posterior tibial translation in all degrees of knee flexion. However, at 90 degrees of knee flexion the strain rate of the posterior cruciate ligament is approximately half that in the fully extended knee and the posterior cruciate ligament is the only ligament to resist posterior tibial translation. CONCLUSIONS: The strain behaviour of the posterior cruciate ligament during injury is highly dependent on the knee flexion during the moment of impact. Forced posterior tibial translation in the 90 degrees flexed knee may result in isolated posterior cruciate ligament deficit rather than a complex ligament disruption. The strain rate of a ligament as introduced in the present study is a quantified parameter related to the resistance that the ligament imposes to an abnormal joint movement. Relevance. This study provides insight into the differential strain of the knee ligaments during impacts that result in posterior cruciate ligament injury. Studies that quantify the strain behaviour of individual knee ligaments are important to the understanding, diagnosis and prevention of injuries sustained during contact sports and high-energy road traffic accidents.

Delirium in the intensive care unit: are we helping the patient?

The intensive care unit (ICU) represents a dynamic interaction between patient factors and interventional factors. The complexity of this situation can generate an impaired consciousness in the patients. The critical care provider is faced with deducing the etiology and treatment of delirium in the ICU. Many of the therapeutic agents that are used in the ICU may precipitate delirium. Patients may also experience delirium as part of their underlying medical conditions. Withdrawal syndromes, delirium tremens in particular, are known to cause delirium. By a combination of appropriate selection of medications and an awareness of delirium as a side effect, the patient in the ICU may be treated in a manner to minimize the clouding of consciousness. An understanding of the proposed pathophysiology of various types of delirium will allow appropriate clinical measures to be taken.

Percutaneous repair of the ruptured tendo Achillis.

Percutaneous repair of the ruptured tendo Achillis has a low rate of failure and negligible complications with the wound, but the sural nerve may be damaged. We describe a new technique which minimises the risk of injury to this nerve. The repair is carried out using three midline stab incisions over the posterior aspect of the tendon. A No. 1 nylon suture on a 90 mm cutting needle approximates the tendon with two box stitches. The procedure can be carried out under local anaesthesia. We reviewed 27 patients who had a percutaneous repair at a median interval of 35 months after the injury. They returned to work at four weeks and to sport at 16. One developed a minor wound infection and another complex regional pain syndrome type II. There were no injuries to the sural nerve or late reruptures. This technique is simple to undertake and has a low rate of complications.

Arthroscopic reconstruction of the anterior cruciate ligament. A comparison of patellar tendon autograft and four-strand hamstring tendon autograft.

We compared the outcome of anterior cruciate ligament reconstruction using hamstring tendon autograft with outcome using patellar tendon autograft at 2 years after surgery. Patients had an isolated anterior cruciate ligament injury and, apart from the grafts, the arthroscopic surgical technique was identical. Prospective assessment was performed on 90 patients with isolated anterior cruciate ligament injury undergoing reconstruction with a patellar tendon autograft; 82 were available for follow-up. The hamstring tendon autograft group consisted of the next 90 consecutive patients fulfilling the same criteria; 85 were available for follow-up. Clinical review included the Lysholm and International Knee Documentation Committee scores, instrumented testing, thigh atrophy, and kneeling pain. These methods revealed no difference between the groups in terms of ligament stability, range of motion, and general symptoms. Thigh atrophy was significantly less in the hamstring tendon group at 1 year after surgery, a difference that had disappeared by 2 years. The KT-1000 arthrometer testing showed a slightly increased mean laxity in the female patients in the hamstring tendon graft group. Kneeling pain after reconstruction with the hamstring tendon autograft was significantly less common than with the patellar tendon autograft, suggesting lower donor-site morbidity with hamstring tendon harvest.

Endoscopic reconstruction for isolated anterior cruciate ligament rupture.

We treated 90 patients with an isolated injury to the anterior cruciate ligament (ACL) by reconstruction using a patellar tendon autograft and interference screw fixation. Of these, 82 (91%) were available for review at 24 months. Two grafts and two contralateral ACLs had ruptured during sport and there was one case of atraumatic graft resorption. Using the assessment of the International Knee Documentation Committee (IKDC), 86% of the remaining patients were normal or nearly normal. The median Lysholm knee score was 95/100 and 84% of patients were participating in moderate to strenuous activity. All had grade-0 or grade-1 Lachman, pivot-shift and anterior-drawer tests. Measurement with the KT1000 arthrometer gave a side-to-side difference of <3 mm of anterior tibial displacement in 90%. Sixty-six radiographs were IKDC grade A and one was grade B. Pain on kneeling was present in 31% and graft site pain in 44%. At 24 months after operation all patients had excellent knee stability, a high rate of return to sport and minimal radiological evidence of degenerative change. Our series therefore represents a basis for comparison of results using other techniques and after more severe injuries.

The use of cold compression dressings after total knee replacement: a randomized controlled trial.

This prospective, controlled study compared cold compressive dressings with wool and crepe in the postoperative management of patients undergoing total knee replacement (TKR). Forty TKR patients were assessed for blood loss, pain, swelling, and range of motion. Patients in the cold compression group had less blood loss through suction drainage (982 mL versus 768 mL). A higher proportion of patients in the treatment group did not require blood transfusion postoperatively. Mean opiate requirements were lower in the cold compression group (0.57 versus 0.71 mg/kg/48 hours). The cold compression device appeared to reduce blood loss and pain following TKR.

Treatment of liver injuries at level I and level II centers in a multi-institutional metropolitan trauma system. The Midwest Trauma Society Liver Trauma Study Group.

OBJECTIVE: The development of trauma systems and trauma centers has had a major impact on the fate of the critically injured patient. However, some have suggested that care may be compromised if too many trauma centers are designated for a given area. As of 1987, the state of Missouri had designated six adult trauma centers, two Level I and four Level II, for the metropolitan Kansas City, Mo, area, serving a population of approximately 1 million people. To determine whether care was comparable between the Level I and II centers, we conducted a concurrent evaluation of the fate of patients with a sentinel injury, hepatic trauma, over a 6-year period (1987-1992) who were treated at these six trauma centers. METHODS: All patients during the 6-year study period who suffered liver trauma and who survived long enough to be evaluated by computerized tomography or celiotomy were entered into the study. Patients with central nervous system trauma were excluded from analysis. Information concerning mechanism of injury, RTS, Injury Severity Score (ISS), presence of shock, liver injury scoring, mode of treatment, mortality, and length of stay were recorded on abstract forms for analysis. Care was evaluated by mortality, time to the operating room (OR), and intensive care unit (ICU) and hospital length of stay. RESULTS: Over the 6-year period 300 patients with non-central nervous system liver trauma were seen. Level I centers cared for 195 patients and Level II centers cared for 105. There was no difference in mean ISS or ISS > 25 between Level I and II centers. Fifty-five (28%) patients arrived in shock at Level I centers and 24 (23%) at Level II centers. Forty-eight patients (16%) died. Thirty-two (16%) died at Level I centers, and 16 (15%) died at Level II centers. Twenty of 55 patients (36%) in shock died at Level I centers, and 11 of 24 (46%) died at Level II centers (p = 0.428). Forty-three patients (22%) had liver scaling scores of IV-VI at Level I centers, and 10 (10%) had similar scores at Level II centers (p < 0.01). With liver scores IV-VI, 22 of 43 (51%) died at Level I centers and 10 of 14 (71%) died at Level II centers (p = 0.184). There was no difference in mean time or in delays beyond 1 hour to the OR for those patients in shock between Level I and II centers. There was a longer ICU stay at Level II centers (5.0 +/- 8.3 vs. 2.8 +/- 8.4 days, p = 0.04). This difference was confined to penetrating injuries. There was no difference in hospital length of stay. CONCLUSIONS: In a metropolitan trauma system, when Level I and II centers were compared for their ability to care for victims of hepatic trauma, there was no discernible difference in care rendered with respect to severity of injury, mortality, delays to the OR, or hospital length of stay. It was observed that more severe liver injuries were seen at Level I centers, but this did not seem to significantly affect care at Level II centers. There was a longer ICU stay observed at Level II centers owing to penetrating injuries, possibly because there were fewer penetrating injuries treated at these facilities. Although the bulk of patients were seen at Level I centers, care throughout the system was equivalent.

Autoimmune bullous diseases.

Patients with autoimmune bullous diseases are occasionally encountered in primary care practice, usually in middle-aged and older patients. The differential diagnosis includes nonimmune causes, such as contact dermatitis, infections and bullous reactions to drugs or insect bites. An autoimmune blistering disease may be distinguished by the age of the patient when the disease first appears, the morphology and distribution of the lesions and the presence or absence of mucosal lesions and scarring. Because the clinical presentations of blistering disorders are often similar, special immunofluorescence tests are used to confirm the specific diagnosis. Since diagnosis and management of an autoimmune bullous disease may involve systems other than the skin, coordination by the primary care physician is crucial.

Changes in crime rates and family-related values in selected East European countries.

Observations and longitudinal comparisons of emerging trends within formerly socialist East European countries offer a unique opportunity to observe some of the social policies typical of the capitalist and socialist systems and their influence on society. Some of the emerging trends in the Czech Republic, former East Germany, and Russia pertaining to general areas of public health, family, and crime are described. Effects of these changes are discussed within the framework of a recently proposed multiple regression model of criminal behavior in which criminality is attributed to the confluence of gross inequalities in the distribution of wealth and to the disintegration of the traditional family. The changes should be considered in the conduct of research.