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Northern Hemisphere midlatitude sporadic E (Es) layer occurrence rates derived from FORMOSAT-3/COSMIC GPS radio occultation (RO) measurements during the Geminid meteor showers 2006-2010 are compared with meteor rates obtained with the Collm (51.3° N, 13.0° E) VHF meteor radar. In most years, Es rates increase after the shower, with a short delay of few days. This indicates a possible link between meteor influx and the production of metallic ions that may form Es. There is an indication that the increase propagates downward, probably partly caused by tidal wind shear. However, the correlation between Es rates and meteor flux varies from year to year. A strong correlation is found especially in 2009, while in 2010 Es rates even decrease during the shower. This indicates that additional processes significantly influence Es occurrence also during meteor showers. A possible effect of the semidiurnal tide is found. During years with weaker tidal wind shear, the correlation between Es and meteor rates is even weaker. [ABSTRACT FROM AUTHOR]

Many injuries to the cervical spine can be treated conservatively. Treatment options include early functional, mobilizing and immobilizing procedures. If a structural injury can be ruled out by morphological imaging, early functional mobilization should be performed in combination with adequate analgesia according to the World Health Organization (WHO) step by step scheme to avoid chronification. If a structural injury to the cervical spine is present, a stability test is crucial for the decision on treatment. Stable fractures include, for example, types I, II and V fractures of the atlas according to Gehweiler, types I and III fractures of the dens axis according to Anderson and D'Alonzo and type A fractures of the subaxial cervical spine according to the AO. If the results of the imaging examination are inconclusive, functional imaging should be performed. If the injury is stable, external immobilization can be used for conservative treatment. Semirigid and rigid cervical orthotic devices as well as Minerva corsets and the halo fixator are available for this purpose. The degree of immobilization increases with the invasiveness of the procedure. Immobilization should be carried out under clinical and radiological monitoring until the injury has healed. An increase or persistence of symptoms during conservative treatment indicates treatment failure and should result in follow-up imaging. Immobilizing treatment should also be accompanied by isometric physiotherapeutic exercise and adequate analgesic treatment. In adult patients the external stabilization should be gradually reduced through physiotherapeutic exercise after completion of the immobilization treatment., Competing Interests: Einhaltung ethischer Richtlinien. Interessenkonflikt: L. Viezens ist als Referent für DePuy Synthes und Medtronic tätig. C. Arras, J. Kylies und L.-G. Leonhardt geben an, dass kein Interessenkonflikt besteht. Für diesen Beitrag wurden von den Autor/-innen keine Studien an Menschen oder Tieren durchgeführt. Für die aufgeführten Studien gelten die jeweils dort angegebenen ethischen Richtlinien., (© 2024. The Author(s), under exclusive licence to Springer Medizin Verlag GmbH, ein Teil von Springer Nature.)

Purpose: Anterior tibial closing wedge osteotomy (ATCWO) has been shown to significantly reduce failure rates of revision anterior cruciate ligament (ACL) reconstructions in patients with a posterior tibial slope (PTS) ≥12°. Recent findings suggest a slight but significant reduction of the medial proximal tibial angle (MPTA) resulting in a varus knee where the sagittal osteotomy plane is based on a total of two guide wires defining the osteotomy wedge without respecting the frontal plane. We hypothesize that the placement of a total of four guide wires intraoperatively can reduce the influence on the MPTA., Methods: This study retrospectively reports on a two-centre series of 42 ATCWOs for PTS correction between January 2022 and December 2023 at two clinical centres. A total of four guide wires were placed based on a true lateral intraoperative view of the tibia, with two positioned each at the cranial and at the caudal pole of the osteotomy wedge, serving as guides for the saw to create the osteotomy, with careful attention to ensuring that the proximal and distal K-Wires were placed parallel to each other. A retrospective analysis was conducted by examining true lateral and anteroposterior radiographs to identify changes in sagittal and coronal plane alignment., Results: The study included 19 women and 23 men, with a mean age of 29.7 ± 8.6 years with first-time ACL revision surgery and a minimum PTS of ≥12°. PTS decreased significantly from 14.5 ± 2.8° preoperatively to 8.2 ± 1.9° post-operatively ( p  < 0.001). The aMPTA demonstrated no significant difference between preoperative (mean aMPTA: 86.9 ± 2.1°) and post-operative (mean aMPTA: 86.6 ± 1.9°) measurements ( p  > 0.05)., Conclusion: With our technique of placing four guide wires to achieve precise guidance during the insertion of the osteotomy wedge, there is no substantial impact on the aMPTA during slope correction., Level of Evidence: Level IV., Competing Interests: The authors declare no conflicts of interest., (© 2025 The Author(s). Journal of Experimental Orthopaedics published by John Wiley & Sons Ltd on behalf of European Society of Sports Traumatology, Knee Surgery and Arthroscopy.)

A clear recommendation regarding treatment strategy of fragility fractures of the pelvic ring is missing. The most typical fracture pattern is a lateral compression type injury with non-displaced fractures of the anterior pubic rami and a unilateral os sacrum fracture (FFP II). We hypothesized that operative treatment would be superior to conservative treatment. From October 2017 to April 2020, a randomized prospective non-blinded trial with n = 39 patients was carried out. Two arms with 17 operative versus 22 conservative cases were created. Inclusion criteria were a posterior pelvic ring fracture FFP type II, age over 60 years and acute fracture (< 3 weeks). Barthel index, pain level (VAS), quality of life (EQ-5D-3L), and Tinetti-Gait Test were determined on admission, at discharge, and after 3, 6, 12 and 24 months. Median follow-up was 12.9 months. The Barthel index (= 0.325), VAS (p = 0.711), quality of life (p = 0.824), and Tinetti-Gait Test (p = 0.913) showed no significant differences between the two groups after 12 months. Two patients switched from the conservative to the operative arm due to persistent immobilization and pain. The one-year mortality rate showed no significant difference (p = 0.175). Our hypothesis that surgical treatment is superior was refuted. No significant benefit was shown in terms of quality of life, mortality and pain levels. The results suggest a more differentiated treatment approach in the future, with initial conservative treatment preferred. A larger multi-center trial is required to confirm these findings.Trial registration: The study was retrospectively registered with the German Clinical Trials Registry (DRKS00013703) on 10/12/2018., (© 2023. The Author(s).)

Introduction: We reported on the superiority of preoperative Duplex mapping ("Duplex") over audible Dopplers ("Doppler") in anterolateral thigh perforator (ALT) free flaps for upper extremity reconstruction. To corroborate our findings on a larger cohort, we conducted this present study focusing on surgical efficiency and patient safety., Methods: 150 consecutive ALT free flaps were divided into 65 cases of preoperative Duplex versus 85 Doppler controls. We first compared patient demographics, operative details, and defect and flap characteristics. We then assessed group differences in the number and course of perforators pursued intraoperatively, flap harvest and operative times, and donor-site complications. Additionally, the impact of the training level of the primary microsurgeon was evaluated., Results: Cases and controls were comparable regarding age (p = .48), sex (p = .81), ASA class (p = .48), and BMI (p = .90). Duplex was associated with an increased likelihood of raising flaps on one single dominant perforator of purely septal course and significant reductions of flap harvest (68 ± 10 min, p < .0001) and operative times (74 ± 16 min, p < .0001), regardless of the experience of the primary microsurgeon. There were strong negative linear correlations between preoperative Duplex and both the flap harvest and operative times (p < .0001). Additionally, while there was no effect on the emergency take-back rate (OR = 1.3, p = .60), revisions were significantly less likely among duplexed patients (OR = 0.15, p = .04)., Conclusions: Preoperative Duplex is associated with a significant reduction in ALT free flap harvest and overall operative times, as well as donor-site revisions as opposed to Doppler planning, regardless of the training level of the primary microsurgeon., (© 2021 Wiley Periodicals LLC.)

This study presents a multi-disciplinary approach for the hydrogeological assessment and characterization of water resources in typical arid and semi-arid areas with high anthropogenic pressure, and where environmental conditions and political context prevent extensive field surveys. The use of a three-dimensional (3D) hydrogeological conceptual model, integrating hydrochemical and multi-isotope data, is proposed for the Batna and Biskra area (NE Algeria). Geological data were assembled in 3D geological software, from which a 3D hydrogeological conceptual model was constructed, which included the delineation of groundwater flow directions. The isotopic characterization, including deuterium and oxygen isotopic composition of water (δ 2 H and δ 18 O), and tritium ( 3 H), provided information regarding recharge sources, flow pathways and residence times of groundwaters. Hydrochemical parameters, measured on the same samples, supported the interpretation of isotope data. All data were processed in a geographic information system (GIS) environment. The effectiveness of this approach was tested on a complex system of aquifers with high hydrogeological heterogeneity. Results show the important role the tectonic setting of an area can play in the hydrogeology and hydrochemistry of its principal groundwater systems. The fault network in the study region connects different aquifers, resulting in the mixing of groundwaters. The region most influenced by geological structures is the southern part of the study area, close to Biskra city. In fact, besides a limited contribution of recharge from rain and surface water derived from flood events, the recharge of the Cenozoic aquifers seems to proceed from the ascension of deeper Cretaceous groundwaters through the fault network, as indicated by temperature, bulk chemistry and in particular δ 2 H, δ 18 O and 3 H results. In contrast, results suggest that the recharge of the low mineralized Maastrichtian waters is primarily influenced by local precipitation and runoff in the mountainous northern part of the study area. Tritium content, low salinity, and bulk chemistry all suggest such waters to be a mix of pre-bomb (deeper flow-lines within the aquifer) and recent water, with no contribution from the deepest Continental Intercalaire groundwaters. The proposed approach reduces ambiguity about the studied aquifer systems, greatly improves the conceptual understanding of their behaviour, and could provide insights into the vulnerability of the aquifers to different anthropogenic pollution phenomena. The methodology used appears to be a valid tool that could be applied to other geographical areas, to inform the design and implementation of efficient management strategies aimed at improving the quality and availability of water resources. Moreover, three-dimensional modelling methods are becoming increasingly applied to different aspects of groundwater management, to obtain a detailed picture of subsurface conditions., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Municipal wastewater treatment plants (WWTPs) discharge micropollutants like pharmaceuticals, pesticides, personal care products or endocrine disrupting chemicals but also nutrients. Both can adversely influence the freshwater ecosystem and may finally affect the ecological conditions. Many studies focus on the potential impact of large WWTPs even if smaller ones are more common, often less efficient and discharge into small creeks or the upper reaches of rivers. As a result, the receiving waters are characterized by relatively high shares of treated wastewater. Thus, the primary objective of this study was to investigate the ecotoxicological effects of a small WWTP on freshwater amphipods and mollusks in a small creek using an active and passive monitoring approach, accompanied by laboratory experiments (LE). In vitro assays with recombinant yeasts and the microtox assay with Aliivibrio fischeri were performed in parallel to determine the endocrine potential and the baseline toxicity. The evaluation of the effects of the analysed WWTP was possible due to its shutdown during our study and the application of the same in vivo and in vitro assays before and after the shutdown. During the operation of the WWTP the discharge of treated wastewater caused significantly higher mortalities and lower reproduction of the anaylsed invertebrates in the active and passive montoring as well as in the LEs. Furthermore, the amphipod species assemblage in the creek was affected downstream of the WWTP effluent. Besides, the endocrine activity and baseline toxicity were significantly higher downstream of the effluent. After the shutdown of the WWTP, the in vitro activity levels and adverse in vivo effects in the receiving water recovered quickly with no significant differences downstream of the former WWTP effluent compared to the upstream station. Furthermore, the previously disturbed amphipod species assemblage recovered significantly with a shift in favor of Gammarus fossarum downstream of the effluent. These biological results are consistent with a marked decline by 81.5% for the detected micropollutants in the receiving creek after the shutdown which points to a prominent role of micropollutants for the observed effects.

Triploid and tetraploid strains of Saccharomyces cerevisiae were constructed and the spontaneous loss during mitosis of one, two or three copies of chromosome VII was determined. In one strain, a triploid (VM2) in which expression of the recessive alleles can be observed only after loss of two copies of chromosome VII (3N-2), the spontaneous frequency of chromosome loss was lower than in the diploid D61.M. In another strain, a tetraploid (VM4) that also requires the loss of two copies of chromosome VII for observation (4N-2) of the recessive alleles, the spontaneous frequency was slightly higher than in the diploid D61.M. The spontaneous frequency of other genetic events (that is, mutation, recombination or chromosome breakage) were lower by 2-3 orders of magnitude than in the diploid strain D61.M. Induction of chromosome loss and other genetic events by nocodazole, ethyl acetate, hydroxyurea and ethyl methanesulfonate was determined in D61.M, VM2, and VM4, and the results were compared. Nocodazole and ethyl acetate induced chromosome loss in both the triploid and the tetraploid strains at lower concentrations than required in the diploid. These compounds also induced elevated frequencies of other genetic events in both the triploid and the tetraploid strains but not in the diploid. Hydroxyurea induced elevated frequencies of chromosome loss in the diploid and the tetraploid. Frequencies of chromosome loss in the triploid treated with hydroxyurea, although elevated, are based on observation of very few colonies of the correct phenotype. Ethyl methanesulfonate failed to induce chromosome loss in any of the three strains. Hydroxyurea and ethyl methanesulfonate did, however, induce very high frequencies of other genetic events.

Induction of hyperploidy in germ cells of male Chinese hamsters treated with vincristine at dose levels of 0.25, 0.50 or 0.75 mg/kg of body weight was investigated. Animals were killed at 6, 24, 48, 72 and 96 h after administration of the chemical by a single intraperitoneal injection. The testes were removed and processed for spermatogonial, meiotic I, and meiotic II metaphases. Significantly increased frequencies of hyperploidy were obtained in meiotic II cells harvested 6, 24 and 48 h but not 72 and 96 h after treatment, indicating the importance of multiple sampling times. Analysis of spermatogonial cells shows that the frequencies of hyperploidy in the treated samples were comparable to those of controls. Limited sampling times used in the present study as well as small sample size or possible loss of hyperploid cells may be responsible for the negative findings for spermatogonial cells. Examination of meiotic I cells from 53 animals reveals the presence of one animal with an elevated level of hyperploidy unrelated to the vincristine treatment.

The utility of Chinese hamsters as a test species for aneuploidy analysis was studied using four chemicals--vincristine, methyl 2-benzimidazole carbamate (MBC), nocodazole, and cyclophosphamide. Ten or more male Chinese hamsters were used per dose and bone marrow was removed at intervals of 6-96 hr. Slides were coded and 50-100 metaphases were analyzed per animal. A metaphase with more than 22 chromosomes was classified as a hyperploid cell, and the data were evaluated by using a one-tailed Fisher's exact test. In experiments using vincristine, MBC, and nocodazole, the frequencies of hyperploid cells were 0.43, 1.14, and 0.91%, respectively, for the control groups. In the experiment using cyclophosphamide, the control value frequency was 3.75%. The treated groups showed no significant increase in hyperploid frequencies when compared to concurrent controls at each of the treated times, except the value at 24 hr for the group that had been treated with vincristine at 0.75 mg/kg. However, this increase was not significant when compared to the overall value for pooled controls, with or without the cyclophosphamide control. Therefore, no significant effects due to chemical treatment were obtained in the present study. The results illustrate the extent of animal-to-animal as well as experiment-to-experiment variability in hyperploid frequencies and the importance of incorporating concurrent controls in assays for aneuploidy.