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For a positive integer M and an odd prime p there exists a map ϖ M from the first homology group of the modular curve X 1 (M) with Z p -coefficients to a second Galois cohomology group over Q (μ M) with restricted ramification and Z p (2) -coefficients. This map takes Manin symbols to certain cup products of cyclotomic M-units. It has previously been shown that if p ∣ M and p ≥ 5 , then ϖ Mp and ϖ M are compatible via the map of homology induced by the quotient X 1 (M p) → X 1 (M) and corestriction from Q (μ Mp) to Q (μ M) . We show that for a prime ℓ ∤ M , ℓ ≠ p ≥ 5 , the maps ϖ M ℓ and ϖ M are again compatible under a certain combination of the two standard degeneracy maps from level M ℓ to level M and corestriction. [ABSTRACT FROM AUTHOR]

Introduction: The most common cause of failure in total hip arthroplasty (THA) is aseptic loosening. Uncemented cup migration analysis by EBRA (Einzel-Bild-Roentgen-Analyse) has shown to be a good predictive indicator for early implant failure if the cup migrates more than 1 milimeter (mm) within the first 2 years after surgery. In this study, we investigated the migration behaviour of an uncemented press-fit cup after 2 years follow-up. Materials and methods: Applying a retrospective study design, we reviewed all consecutive patients who received an uncemented press-fit cup at our Department between 2013 and 2018. A total of 484 patients were identified. We reviewed medical histories and performed radiological measurements using EBRA-Cup software. EBRA measurements and statistical investigations were performed by two independent investigators. Results: A total of 165 cups in 159 patients (female: 90; male: 69) met our inclusion criteria. Mean age at surgery was 66.7 (range 18.4–90.5) years. EBRA migration analysis showed a mean total migration of 0.7 mm (range 0.0–6.3) over our follow-up period of 2 years. Of the investigated cups, 53.2% showed less than 1 mm migration in the investigated follow-up period. Conclusion: In conclusion, the Pinnacle cup used in our study provides low mean migration at final follow-up. Based on the assumption of secondary stabilization, good long-term outcome of the Pinnacle cup can be expected. Trial registration number and date of registration: Number: 20181024-1875; Date: 2018-09-20 [ABSTRACT FROM AUTHOR]

This paper aims to analytically, experimentally, and numerically study the hydro-mechanical deep drawing (HMDD) process of bimetallic specimens. The blank included aluminum and steel sheets used to produce double-layer conical-spherical cups. The punch geometry, maximum fluid pressure, pre-bulge pressure, layer arrangement, and the drawing depth were the process parameters investigated in this article. Two criterions based on the thickness strain and thickness variation were used to assess the effects of these variables on the quality of the final product. The results of the analytical modeling and numerical simulations were verified by comparing with the related experimental data. Different outcomes were in acceptable agreement with each other. Based on the findings obtained, by increasing the fluid pressure up to 15 MPa, the quality of the final product was enhanced. Moreover, by applying the pre-bulge pressure in the HMDD process, the separation between the layers as well as the thickness variation decreased. The highest improvements in the values of the maximum thickness strain and thickness variation in the current investigation were gained to be 57% and 68%, respectively, in comparison with the traditional state of the deep drawing process. [ABSTRACT FROM AUTHOR]

Background: Limiting the risk of dislocation is one of the main aims of both dual mobility and Lefèvre retentive cups. However, these devices have never been compared. The goal of our study was to compare these devices in total hip arthroplasty revisions for instability. The judgement criterion was non-recurrence of dislocation in a follow-up period of eight years.Methods: This retrospective case-control study compared two continuous paired series of total hip arthroplasty revisions for instability. These series included 63 patients and 159 patients with implantation of a Lefèvre retentive cup and a dual mobility cup, respectively.Results: The success rate at eight years (i.e., no recurrence) was 91 ± 0.05% and 95 ± 0.02% in the Lefèvre retentive cup and dual mobility groups, respectively. The difference was not statistically significant (p = 0.6).Conclusion: It seems that the Lefèvre retentive cup provides comparable outcomes with the dual mobility cup in the total hip arthroplasty revisions for instability, avoiding recurrence in long term. [ABSTRACT FROM AUTHOR]

In this study, sheet bulk metal forming (SBMF) processes for manufacturing sidewall-thickened cups were explored, including sheet forming processes for the preparation of cup billets and bulk forming processes for sidewall thickening. To avoid forging laps caused by the clearance between the cup corner and die during sidewall upsetting, a locally thickened tailored blank was designed and produced. To form tailored blanks, coining and orbital forming were compared, and a strategy based on a coining process with different lubrication conditions was analyzed. The tailored blanks were drawn to cups, which had sharp corners and were used as billets for the final upsetting operation to avoid the clearance and thus eliminate forging laps. Adopting upsetting with controllable deformation zone (U-CDZ) method, the cup sidewall was thickened. During forming, the buckling on the sidewall and laps on the corner were prevented. The numerical and experimental results indicate that sheet parts with complex sections can be formed using a tailored blank with the U-CDZ method. [ABSTRACT FROM AUTHOR]

Purpose: To compare the radiographic migration profiles of primary cementless total hip arthroplasty (THA) between patients with rheumatoid arthritis (RA) and those with osteoarthritis (OA).Methods: A total of 197 patients (215 hips) who underwent cementless THA for RA or OA between January 2001 and January 2013 and followed up for a minimum of 5.5 years were included. Ninety-four RA patients (109 hips) were compared with 103 OA patients (106 hips). Radiological evaluation was performed for acetabular cup loosening, and cup migration was measured using Einzel-Bild-Röntgen-Analyse (EBRA) software. Multiple variables were assessed to identify influencing factors for cup migration.Results: Early cup migration was observed in 13 hips (11.9%) in the RA group and four hips (3.8%) in the OA group, showing a significant difference (p = 0.041). Acetabular cup loosening occurred in three cups (2.8%) in the RA group and in one cup (0.9%) in the OA group, showing no significant difference (p = 0.321). Total cup migration was higher in the RA group (2.62 mm) than in the OA group (1.44 mm, p = 0.005). Total cup migration was significantly higher in patients aged < 50 years than in those aged > 50 years (p = 0.005). Rheumatoid factor (RF) and anti-cyclic citrullinated peptide (anti-CCP) antibody influenced total cup migration. Patients with seropositive RA showed significantly higher total cup migration and early cup migration incidence than those with seronegative RA (p = 0.005, p = 0.038, respectively).Conclusions: Acetabular cups in primary cementless THAs of RA patients were less stable in terms of cup migration compared with that of OA patients. [ABSTRACT FROM AUTHOR]

Atterberg limits of soils including the liquid limit are one of the oldest and most traditional tests conducted in geotechnical site investigations. The relationship between the liquid limits determined from the Casagrande percussion cup apparatus and the fall-cone device has been extensively studied. Despite the known convenience of the fall-cone method, it is scarcely employed for geotechnical site investigations in the USA. This paper presents the findings of investigations conducted on 65 soil samples from different parts of the Indiana State in the USA including their liquid limit tests. The results obtained by the Casagrande percussion cup method and the fall-cone method were compared. The comparison explains how the variations in the liquid limit effect the results of the two methods, and a correlation is also offered. Based on the results, a model is also presented for single-point determination of the liquid limit from the two methods. Finally, a modified plasticity chart for soil classification is proposed based on the fall-cone liquid limit and plasticity index results of these soil samples. The paper also includes the statistical analysis of the proposed relationships. [ABSTRACT FROM AUTHOR]

Introduction: Although the advantages of total hip arthroplasty (THA) using the direct anterior approach (DAA) have been well documented, DAA in the supine position is limited by the difficulty in exposing the acetabulum and femur, which may result in implant malpositioning and intra-operative complications. Recent studies have reported that DAA-THA in the lateral position can achieve satisfactory clinical and radiographic outcomes. The aim of this study was to investigate the difference in implant alignment between two patient cohorts that underwent primary THA by DAA and the traditional posterolateral approach (PLA) in the lateral position.Methods: A total of 208 THAs (110 using DAA and 98 using PLA) were retrospectively analyzed.Results: The cup anteversion angle was closer to the target anteversion angle, and the accuracy of cup orientation was superior in the DAA group. A total of 82 (74.5%) DAA-THA and 56 (57.1%) PLA-THA cases showed successful inclination and anteversion angles (p = 0.008) of the implant. In addition, 90 (81.8%) DAA-THA and 67 (68.4%) PLA-THA cases had successful anteversion angle (p = 0.024). There was no significant difference between the two groups in terms of successful inclination angle (98 vs. 81, p = 0.181), as well as in the stem alignment in both coronal and sagittal planes.Conclusion: THA using DAA in the lateral position can achieve superior cup orientation compared to PLA while maintaining the stem alignment. [ABSTRACT FROM AUTHOR]

Purpose: Dislocation and peri-prosthetic fracture (PPF) are major reasons for revision THA (total hip arthroplasty). The main advantage of dual mobility (DM) cups is to minimize the incidence of dislocation compared to single mobility (SM) cups. We hypothesized that the use of DM would lead to an increased risk of PPF because of its greater stability. In contrast, standard cups would be at higher risk of dislocation.Methods: A retrospective comparative study was performed in our institution including 126 revision THAs between January 2013 and December 2017. Collected data included gender, age, BMI, Parker score, ASA score, the etiology for primary THA, type of cup (SM or DM), cortical index, Noble index, and the stem fixation.Results: Overall, 53 standard and 73 DM cups were included for study. In the dislocation group, 29 had standard cups (83%) and 6 had DM cups (17%). Dislocation was 12-fold higher in SM cups (p < 0.001). In the PPF group, 24 had standard cups (26%) and 67 had DM cups (74%). PFF was 12-fold higher for DM cups (p < 0.001). A higher Parker score and a higher cortical index had a protective effect on the risk of PPF (OR = 0.76 (p = 0.03), OR = 0.57 (p = 0.048)).Conclusion: The use of DM increased hip stability but led to a higher rate of PPF by load transfer on the femur. Further studies with larger cohort and follow-up are needed to confirm these findings and measure the incidence of these complications. [ABSTRACT FROM AUTHOR]

The formability of 1 mm thick AA5182 aluminum alloy sheets in deep drawing of square cups by hydroforming was studied. The influence of process parameters (peak pressure, pressure path, and blank holding force) on formability was investigated through numerical simulations and validated with experimental work. The experiments were designed using the Taguchi method. The minimum thickness in the formed cups (at the bottom corners) and the minimum corner radius that can be achieved were considered as the criteria for evaluation of formability. The peak pressure was the most important process parameter affecting thinning and the minimum corner radius that can be achieved. The variation of the pressure path had the least effect on formability. Regression models were developed for prediction of minimum thickness in the cup and the corner radius as a function of peak pressure and blank holding force. [ABSTRACT FROM AUTHOR]

Introduction: Instability is a major complication in revision total hip arthroplasty (THA). Dual mobility (DM) cups were shown to reduce the risk of post-operative implant dislocation. Few case-series studies assessed the outcomes of cemented DM cups when associated to acetabular reconstruction antiprotrusio cages. No published comparative studies were found to look for outcome differences between standard cups (SC) and DM cups in first revision THA associated with a Kerboull plate (KP) and acetabular bone grafting.Materials and Methods: This is a retrospective comparative study of two groups of patients in two institutions. All cases were first revision THA with KP reconstruction; a cemented standard cup (SC) was used in one institution (THA-SC group) while a cemented DM cup was used in the second institution (THA-DM group). The posterolateral approach and the same technique for KP placement, the cross technique, were performed in both groups. Primary outcomes were dislocation and revision rates. Survivorship and clinical and radiological results were set to be secondary outcomes. There were ten patients (13 hips) in the first group and 16 patients (16 hips) in the second with a mean follow-up clinical and radiological evaluation of 74.2 ± 47.9 months.Results: Besides age, no significant demographic differences were present between both groups. There were three dislocations (23%) in the first group treated with close reduction compared to none in the second (p = 0.04). No further episode of dislocation or revision surgery occurred until the last follow-up in both groups. The mean Harris Hip Scores for the THA-SC and THA-DM groups were 87.5 ± 10.9 and 87.4 ± 12.1, respectively. When present, radiolucent lines were less than 1 mm thick and were non-progressive in both groups. In all patients, complete trabeculation remodeling or cortical repair of the graft was observed.Conclusion: The cup type was the single variable which could account for the observed dislocation rate difference. The mid-term results of using DM cups with KP in first revision THA seem very encouraging. Our findings add to the previously published results on the excellent outcomes in terms of stability in revision THA when using DM cups. [ABSTRACT FROM AUTHOR]

Purpose: Intraoperative pelvic motion can alter the perceived cup inclination and version during non-navigated THA. We quantified pelvic motion during different phases of primary THA performed in the lateral decubitus through a posterolateral approach.Methods: Pelvic roll (rotation of the coronal plane) and pitch angles (rotation parallel to the coronal plane) were studied in 75 patients undergoing THA for osteoarthritis by four arthroplasty surgeons. Ten steps of surgery were defined. Angular motion was recorded with a miniature surgical device that utilizes inertial sensors.Results: The mean absolute roll ranged from 0.03° detected at the end of surgery to 4.13° detected during acetabular exposure. The mean absolute pitch ranged from 0.05° detected at the end of surgery to 2.54° detected during hip dislocation. The maximum pelvic roll and pitch detected during surgery averaged 17.62° (SD: 5.08) and 9.3° (SD: 3.39) respectively. Absolute roll and pitch angles were not affected by patient's BMI, sex, pre-operative hip motion, or surgeon. Before cup insertion, the greatest mean change in roll was observed during acetabular exposure (10.02° anteriorly), and for pitch was observed during dislocation (1.88° caudally).Conclusion: During THA performed through a posterolateral approach, there is a progressive anterior pelvic roll that peaks before cup insertion. This can lead to underestimation of cup anteversion during non-navigated THA. The anterior roll does not completely correct, even when all retractors and external forces acting on the pelvis are removed. Pelvic pitch that could affect the perceived cup inclination occurs to a lesser extent than pelvic roll. [ABSTRACT FROM AUTHOR]

Introduction: Acetabular revision arthroplasty using jumbo cups for moderate-to-severe acetabular defects has varied outcomes. We evaluated the clinical and radiological outcomes of acetabular revision arthroplasty using a press-fitted jumbo cup and sought to identify factors that influence outcomes during intermediate follow-up.Materials and Methods: Eighty patients (47 men, 33 women; 80 hips) who underwent acetabular revision arthroplasty using press-fitted jumbo cups were included. The mean follow-up period was 10.4 years. Harris hip score (HHS), presence of groin pain, radiographic results, and Kaplan-Meier survival curves were evaluated. Implant design and surgery-related and patient-related factors were assessed to identify influential factors for cup loosening. Migration and wear analyses were performed using Einzel-Bild-Röntgen-Analyse software.Results: The mean preoperative HHS of 53 had improved to 77 at the final follow-up (p = 0.005). Nine patients experienced groin pain. Acetabular cup loosening was observed in seven cups (8.7%), and one jumbo cup was replaced with a reinforcement cage. The survival rate of the acetabular cup was 91% at 16 years according to the Kaplan-Meier analysis. Osteolysis was identified around the cup in six cases (7.5%). Acetabular cup loosening occurred more frequently in patients with conventional polyethylene liners than in those with highly cross-linked polyethylene liners (p = 0.045). The mean total migration was 1.52 mm, and the mean total wear was 0.98 mm. There was a positive correlation between total migration and total wear (p = 0.023; Spearman's rho = 0.388). The mean wear rate of the patients with the cup inclination angle < 50° was significantly lower than those with the cup inclination angle > 50° (p = 0.001). There were four cases of complications (three dislocations and one infection) that did not require revision surgery.Conclusion: Press-fitted jumbo cups for acetabular revision arthroplasty exhibited encouraging results during follow-up for an average of 10 years. Use of highly cross-linked polyethylene liners and proper placement of the acetabular component with an inclination angle < 50° may contribute to better clinical outcomes after acetabular revision arthroplasty with jumbo cups. [ABSTRACT FROM AUTHOR]

Purpose: Although long-term reports of total hip arthroplasty (THA) showed successful results, instability remains a major complication. Recently, dual-mobility cups (DMC) have gained more and more interest among clinicians, with encouraging results in terms of lower rate of dislocation associated with good clinical results, but a lack of evidence exists regarding the real efficacy of this implant design compared to traditional fixed-bearing total hip arthroplasties.Methods: A systematic search was performed in PubMed, Google scholar, Cochrane Library, and EMBASE by two independent reviewers for comparative studies available till December 2017, with the primary objective to demonstrate a real lower dislocation rate of DMC implants compared to unipolar fixed-bearing cup designs. A meta-analysis was conducted with the collected pooled data about dislocation rate, calculating the risk difference (RD) and relative risk (RR) with 95% CI for dichotomous variables. Heterogeneity was tested using the χ2 and Higgins' I2 tests. A fixed-effect model was used because the statistical heterogeneity was below 50%.Results: After performing a critical exclusion process, the number of eligible studies included for final synthesis considered was 15, describing the results of a total of 2408 total hip arthroplasties (50.6% with a dual-mobility acetabular cup design, 49.4% with a standard fixed-bearing design). The fixed-effect meta-analysis showed a slight significant risk ratio of 0.16 (95% CI, 0.09, 0.28; I2 = 0%, p < 0.00001); a statistically significant difference in favor of the DMC group was maintained also considering only primary or revision arthroplasties, traumatic fractures or elective patients with diagnosis of osteoarthritis, avascular osteonecrosis or rheumatic arthritis.Conclusions: With the intrinsic limitations of our study design and based on the current available data, this study demonstrates that dual-mobility acetabular components decrease the risk of post-operative instability also in high-risk patients, both in primary and revision hip arthroplasties. However, new high-quality studies, possibly with a randomized control design, should be undertaken in order to strengthen the present data.Study Design: Level of Evidence III, therapeutic study. [ABSTRACT FROM AUTHOR]

Purpose: Despite interest in an environmentally conscious decision between disposable and reusable cups, a comprehensive and current study for US consumers is not yet available. Guidance in favor of single-use cups rely on outdated or non-ISO-compliant results with limited uncertainty information. Such claims are insufficiently generalizable. This article delivers an updated comparative life cycle impact assessment of reusable ceramic cups and single-use expanded polystyrene cups. Methods: The ReCiPe midpoint model was selected. Scenario uncertainties are addressed by evaluating compliant standard dishwashing appliance models from 2004 to 2013 used in 26 US subregional utility grids. A utility snapshot from 2009 is applied with extension to recent shifts in generation from increased penetration of natural gas and renewable energy. Parameter uncertainty is quantified through statistical methods. Results: Where there is statistical difference, results almost entirely favor reusable cups in the USA. For climate change, 16 % of users have higher impact for ceramic cups washed in 2013 by minimally compliant dishwashers. Higher climate change impacts for 32 % of reusable cup users is indicated with 2004 average dishwashers, though using a cup twice between washes shifts the impact in favor of the reusable cup. Conclusions: Disposable cup scenarios do not account for film sleeves, lids, printing, and less conservative shipping weights and distances and therefore reflect a best case scenario. Impact for reusable cups is expected to decrease further as the electricity mix becomes less CO-intensive with replacement of coal-fired generators by natural gas, wind, and solar and as less efficient dishwashers are replaced with new units compliant to current laws. [ABSTRACT FROM AUTHOR]

Background, aim, and scope At the request of the Public Waste Agency for the Flemish Region, the Flemish Institute for Technological Research performed a life cycle assessment (LCA), according to the International Organization for Standardization (ISO) 14040 procedures (ISO 1997, 1998, 2000, and ISO 2006), followed by an eco-efficiency analysis of four alternative types of drinking cups for use at public events. The results of the LCA study served as input for the eco-efficiency analysis in which the costs related to the four cup systems were studied and combined with the environmental impacts. The objective of this study was to gain insight into the current environmental impacts and costs related to existing systems for drinking cups at public events in Flanders (Belgium) in order to outline a well-founded policy with regard to this subject. Since the results of this comparative study are publicly available, a critical review was performed according to ISO 14040 (review by interested parties, using a review panel) after each stage (goal and scope, data inventory, impact analysis/ interpretation, eco-efficiency analysis) during the study. Methodology Four types of cups were analysed; the reusable polycarbonate cup (PC), the one-way polypropylene cup (PP), the one-way PE-coated cardboard cup and the one-way polylactide cup (PLA). The functional unit is defined as 'the recipients needed to serve 100 l of beer or soft drinks at a small-scale indoor respectively a large-scale outdoor event'. This definition included the production of the cups, the consumption stage (at the event) and the processing of the waste. The data inventory focused on specific data supplied by different stakeholders in Flanders (and Belgium). Based on data collected for specific events, an average typical small indoor and large outdoor event was defined, respectively. One important aspect in this context was the trip rate for the reusable cups, meaning the average number of times one cup can be used before disposal. Based on practical experiences combined with literature research, a trip rate was defined for small- and large-scale events, respectively. Since this factor was very important but also very open for debate, a sensitivity analysis was performed on the trip rate. The impact analysis was based on the Eco-Indicator 99 methodology (Hierarchist version H/A; Goedkoop and Spriensma 2000). The main reason for using this methodology was that it allows the calculation of one weighted environmental indicator for each alternative, which was needed as input for the eco-efficiency analysis. The cost indicator, which was based on similar system boundaries and assumptions as the environmental indicator, was calculated from a societal perspective. Both indicators were combined in an eco-efficiency portfolio, with the average in the centre point and the number of standard deviations indicated on the axes. Results and discussion For the environmental profile of the individual cup systems, the total life cycle of the cups was divided in different life cycle stages.… [ABSTRACT FROM AUTHOR]

Knowing that objects continue to exist after disappearing from sight and tracking invisible object displacements are two basic elements of spatial cognition. The current study compares dogs and apes in an invisible transposition task. Food was hidden under one of two cups in full view of the subject. After that both cups were displaced, systematically varying two main factors, whether cups were crossed during displacement and whether the cups were substituted by the other cup or instead cups were moved to new locations. While the apes were successful in all conditions, the dogs had a strong preference to approach the location where they last saw the reward, especially if this location remained filled. In addition, dogs seem to have especial difficulties to track the reward when both containers crossed their path during displacement. These results confirm the substantial difference that exists between great apes and dogs with regard to mental representation abilities required to track the invisible displacements of objects. [ABSTRACT FROM AUTHOR]

A white pigment found on a sub-set of polychromed wooden Andean ritual drinking cups called qeros has been characterized by X-ray diffraction, X-ray fluorescence spectroscopy and Raman spectroscopy as consisting principally of cristobalite (SiO2), anatase (TiO2), and α-quartz (SiO2). This unexpected assemblage of minerals is like that reportedly found in an exposed titanium ore body in southern Peru, an area once part of the Inka Empire. The ore is a close match in color and composition to the white pigment found on the qeros and offers a possible candidate for the geological source of this material. The temporal horizon for the use of this pigment appears to be ca. 1532-1570, correlating with what we refer to here as the Transitional Inka/Early Colonial period, although production of polychromed qeros may have begun before this time and certainly continued well into the eighteenth century or later. Not long after the arrival of the Spanish, this titanium dioxide/silica pigment was replaced by lead white, a result of Spanish influence. We suggest that white pigments on qeros offer material evidence for establishing a chronology for these ritual vessels and that the titanium dioxide/silica pigment on this group of qeros constitutes a previously unidentified, naturally occurring white pigment indigenous to the southern Andes, the first use of which probably dates to the Pre-Columbian period. [ABSTRACT FROM AUTHOR]

Compares the relative merits of reusable and disposable cups by examination of their respective energy cost. Component technologies required to make various cup types; Information on hot water and operating energy requirements of commercial dishwashers; Cup comparison energy matrix; Selection of appropriate cup types for different public service situations.