bluuebunny/crossref_metadata_2025 huggingface dataset:
Light wave filtration by colored cellophane to optimize microscopic contrast ratio in pulmonary tuberculosis sputum observation
Authors: Edbert Daniel , Mertaniasih Ni Made , Endraswari Pepy Dwi , Koendhori Eko Budi
Published: March 2022

Introduction: Indonesia has the second highest number of Tuberculosis (TB) in the world and tuberculosis still pose as a global health priority problem. For the diagnostics, microscopy is still one of important modalities in TB diagnosis especially in peripheral areas for screening, case-finding, and treatment evaluation. The use of microscopy is limited to operator visual burden and specimen load. This study aims to modify the use of the microscope by using everyday item to increase microscope operator workload.

Method: This is an analytic study of the use of colored cellophane in microscopic examination of sputum smear from 24 pulmonary TB patients from Jakarta and Surabaya. The sputum samples were confirmed positive by standardized ZN-AFB microscopy and/or Xpert MTB/RIF. Each sputum were made into two slides, for each slide, 10 oil immersion fields were captured using Optilab microscope camera mounted on microscope. A total of 480 data pairs were analysed by comparing color characteristic of acid-fast bacilli pixels and its adjacent background pixels and by counting Acid fast Bacilli for each observation field. IUATLD scale were also observed by 3 operators.

Results: Contrast ratio for each AFB and its adjacent pixels were significantly higher in groups using cellophane filter than without using filter (p = 0.001). AFB identification per image acquired using filter were not significantly higher (p=0.815).

Conclusion: Colored cellophane increases contrast ratio and eases microscopic examination, thus increases sputum smear microscopic observation capability. Also it might increase identification capability with digital image processing.
Protocol for a feasibility study of longitudinal surveys to assess the impact of policies on tobacco use among school-going adolescents in South Asia
Authors: Mishu Masuma Pervin , Siddiqi Kamran , McNeill Ann , Kanaan Mona , Jackson Cath , Huque Rumana , Kanan Sushama , Abdullah S.M. , Fieroze Fariza , Garg Suneela , Singh M. Meghachandra , Borle Amod L. , Deshmukh Chetana , Akhter Zohaib , Mazhar Laraib , Khan Zohaib , Rehman Khalid , Ullah Safat , Han Lu , Readshaw Anne , Iqbal Romaina
Published: March 2022

Background: Smokeless tobacco (ST) use is common among youth in South Asia where 85% of the world’s 300 million ST users live and use the most lethal ST forms. Little is known about the impact of tobacco control policies on the youth ST uptake in those countries. We planned to conduct longitudinal surveys among school going adolescents to evaluate existing tobacco control policies on tobacco uptake and use, and a feasibility study for that prospective, observational cohort study.

Study objectives: (1) To demonstrate the feasibility of selection, recruitment and retention of schools and of study participants; (2) To assess the feasibility and acceptability of the study procedure and study tool (questionnaire); (3) To evaluate if the questionnaire can assess tobacco uptake and use, and their potential predictors.

Methods and analysis: The feasibility study will be conducted in two administrative areas within each of three South Asian countries: Bangladesh, India and Pakistan. We will use both quantitative and qualitative data collection methods. Eight eligible schools will be randomly selected within purposively selected sub-districts from each country. We plan to conduct one baseline and one follow up survey among students of grade 6-8, one year apart. At each time point, data on tobacco uptake and potential predictors will be collected from students via self-administered questionnaires that were designed for the longitudinal study. The qualitative component will be embedded into the study with each round of data collection to assess the acceptability of the study instrument (questionnaire) and data collection methods, via focus group discussions with students and semi-structured interviews with schoolteachers.

Recruitment and retention rates, completeness of the questionnaires, frequencies and associations of tobacco use and explanatory variables will be reported. Data gathered from the focus group and interviews will be analysed using the framework approach.
Secure Optimized Request Zone Location-Aided Routing
Authors:   Tafila Technical University, Tafila 66110, Jordan, Saleh Maen S.
Published: March 2022

Secure data transmission is one of the biggest challenges for Vehicular Ad Hoc Networks (VANETs) due to its dynamic and infrastructure-less characteristics. Such security services become a demand to provide safe and secure conversation between automobiles. In this paper, two optimized secure routing protocol for VANETs were proposed: 1) Secure Tilted-Rectangular-Shaped Request Zone Location-Aided Routing protocol (STRS-RZLAR); 2) Secure Cone-Shaped Request Zone LAR (SCS-RZLAR). Each proposed secure protocol integrates a security unit with an optimized shape request zone. The security unit in both protocols is a multi-layer unit that adopts two security agreement protocols: 1) modified Diffie-Hellman key agreement protocol; 2) short authentication string (SAS)-based key agreement protocol. The overall communication scheme is performed using Wi-Fi Direct out-of-band channels. The proposed secure protocols provide a reliable and secure data transmission between automobiles in a VANET and thus making it robust against man-in-the-middle attack (MITMA). Extensive simulations using three main network parameters: vehicular node density, number of malicious nodes and vehicle speed show that the proposed secure routing protocols provide superior performance regarding data delivery and normalized routing load (NRL) with a trade-off in average end to end packet delay. From the other side, Simulation results show that SCS-RZLAR protocol outperforms the STRS-RZLAR protocol regarding NRL and average end to end packet delay, while STRS-RZLAR protocol outperforms the SCS-RZLAR protocol regarding data delivery.
Inductive Representation Learning on Dynamic Stock Co-Movement Graphs for Stock Predictions
Authors: Tian Hu , Zheng Xiaolong , Zhao Kang , Liu Maggie Wenjing , Zeng Daniel Dajun
Published: March 2022

Co-movement among individual firms’ stock prices can reflect complex interfirm relationships. This paper proposes a novel method to leverage such relationships for stock price predictions by adopting inductive graph representation learning on dynamic stock graphs constructed based on historical stock price co-movement. To learn node representations from such dynamic graphs for better stock predictions, we propose the hybrid-attention dynamic graph neural network, an inductive graph representation learning method. We also extended mini-batch gradient descent to inductive representation learning on dynamic stock graphs so that the model can update parameters over mini-batch stock graphs with higher training efficiency. Extensive experiments on stocks from different markets and trading simulations demonstrate that the proposed method significantly improves stock predictions. The proposed method can have important implications for the management of financial portfolios and investment risk.

Summary of Contribution: Accurate predictions of stock prices have important implications for financial decisions. In today’s economy, individual firms are increasingly connected via different types of relationships. As a result, firms’ stock prices often feature synchronous co-movement patterns. This paper represents the first effort to leverage such phenomena to construct dynamic stock graphs for stock predictions. We develop hybrid-attention dynamic graph neural network (HAD-GNN), an inductive graph representation learning framework for dynamic stock graphs to incorporate temporal and graph attention mechanisms. To improve the learning efficiency of HAD-GNN, we also extend the mini-batch gradient descent to inductive representation learning on such dynamic graphs and adopt a t-batch training mechanism (t-BTM). We demonstrate the effectiveness of our new approach via experiments based on real-world data and simulations.
Price Optimization Under the Finite-Mixture Logit Model
Authors: van de Geer Ruben , den Boer Arnoud V.
Published: March 2022

We consider price optimization under the finite-mixture logit model. This model assumes that customers belong to one of a number of customer segments, where each customer segment chooses according to a multinomial logit model with segment-specific parameters. We reformulate the corresponding price optimization problem and develop a novel characterization. Leveraging this new characterization, we construct an algorithm that obtains prices at which the revenue is guaranteed to be at least [Formula: see text] times the maximum attainable revenue for any prespecified [Formula: see text]. Existing global optimization methods require exponential time in the number of products to obtain such a result, which practically means that the prices of only a handful of products can be optimized. The running time of our algorithm, however, is exponential in the number of customer segments and only polynomial in the number of products. This is of great practical value, because in applications, the number of products can be very large, whereas it has been found in various contexts that a low number of segments is sufficient to capture customer heterogeneity appropriately. The results of our numerical study show that (i) ignoring customer segmentation can be detrimental for the obtained revenue, (ii) heuristics for optimization can get stuck in local optima, and (iii) our algorithm runs fast on a broad range of problem instances.

This paper was accepted by Omar Besbes, revenue management and market analytics.
Solving Nonsmooth and Nonconvex Compound Stochastic Programs with Applications to Risk Measure Minimization
Authors: Liu Junyi , Cui Ying , Pang Jong-Shi
Published: March 2022

This paper studies a structured compound stochastic program (SP) involving multiple expectations coupled by nonconvex and nonsmooth functions. We present a successive convex programming-based sampling algorithm and establish its subsequential convergence. We describe stationary properties of the limit points for several classes of the compound SP. We further discuss probabilistic stopping rules based on the computable error bound for the algorithm. We present several risk measure minimization problems that can be formulated as such a compound stochastic program; these include generalized deviation optimization problems based on the optimized certainty equivalent and buffered probability of exceedance (bPOE), a distributionally robust bPOE optimization problem, and a multiclass classification problem employing the cost-sensitive error criteria with bPOE.
Optimistic Gittins Indices
Authors: Farias Vivek F. , Gutin Eli
Published: March 2022

We propose a tightening sequence of optimistic approximations to the Gittins index in “Optimistic Gittins Indices.” We show that the use of these approximations in concert with the use of an increasing discount factor appears to offer a compelling alternative to state-of-the-art index schemes proposed for the Bayesian multiarmed bandit problem. We prove that the use of these optimistic indices constitutes a regret optimal algorithm. Perhaps more interestingly, the use of even the loosest of these approximations appears to offer substantial performance improvements over state-of-the-art alternatives while incurring little to no additional computational overhead relative to the simplest of these alternatives.
Driven to Distraction: The Unintended Consequences of Organizational Learning from Failure Caused by Human Error
Authors: Park Brian , Lehman David W. , Ramanujam Rangaraj
Published: March 2022

Research to date offers inconclusive and even conflicting evidence regarding whether organizations learn from failure. The present study sheds new light on this debate by highlighting a previously overlooked factor: whether the failure was caused by human error. In attempts to learn from failure, organizational members tend to focus on simplified representations of experiences and, in doing so, distinguish between failures attributed to human errors versus other causes. Our core thesis is that failures resulting from human error attract significant amounts of attentional resources, thereby depleting the limited stock of organizational attention otherwise directed at managing the risk of failures resulting from other causes. We hypothesize that this disproportionate allocation of attention simultaneously is associated with both positive learning outcomes and negative side effects, specifically, a subsequent decrease in failures resulting from human error and also an increase in failures resulting from other causes. We also hypothesize that failures resulting from causes other than human error attract less organizational attention and, thus, lead to weaker learning outcomes. The proposed hypotheses were tested and supported using data from accident reports filed by natural gas pipeline operators with the U.S. Pipeline Hazardous Materials Safety Administration from 2002 to 2012. Additional analyses, including text analysis of accident reports, a series of simulations, and a supplementary study, point to organizational attention as the mechanism at play. Taken together, these findings suggest that organizational learning from failure caused by human error produces not only benefits, but also unintended consequences.
Removal of Cadmium, Copper and Lead from Aqueous Solution Using Activated Carbon Prepared from Avocado Kernel
Authors: Chimdessa Mitiku Abdisa , Ejeta Birhanu Aseffa
Published: March 2022

Toxic heavy metal ions are extremely harmful to living things and the environment due to their toxicity, carcinogenicity, ability to collect in nature, and capacity to contaminate surface and ground water. The focus of this research was to develop an appropriate and low cost adsorbent for the removal heavy metal ions from aqueous solutions. The activated carbon was prepared from avocado kernels and characterized by using XRD, FTIR, and pHPZC. From the XRD spectra the crystal size of AC-1 and AC-2 were calculated. The sample with the smallest crystallite size (40.05 nm) was found to be AC-1 and chosen for the further characterization and sorption experiments. Batch studies on synthetic samples were performed at room temperature. pH effect, initial concentration, adsorbent dosage, initial concentration, and contact time were investigated and also heavy metal ion adsorption isotherms were calculated. At pH 7, the highest removal effectiveness of metals (copper, cadmium, and lead) by activated carbon adsorbent made from avocado kernel was achieved. The best adsorbent dose for cadmium and lead was 500 mg, 700 mg for copper, and the optimum contact times for lead, cadmium and copper ions were 120, 60 minutes, respectively. In these optimum conditions the removal efficiencies were 87%, 89.4%, and 99.5% for copper, Lead, and Cadmium ions respectively. The removal efficiencies for copper, lead, and cadmium ions were 87 %, 89.4 %, and 99.5 %, respectively, under these optimal conditions. The Langmuir isotherm model has the strongest correlation with the obtained results. According to the findings, activated carbon made from avocado kernels has high adsorption capacity for removing heavy metal ions from aqueous solutions.
Studies on Oxidation of Alcohols by Cerium (IV)-dimer in Aqueous Nitric acid
Authors: Bhuwan Chandra Bhuwan Chandra , Tamta Anshu , Rashmi Khulbe Rashmi Khulbe , Asha Kandpal Asha Kandpal , N.D. Kandpal N.D. Kandpal , Kailash Tamta Kailash Tamta
Published: March 2022

The oxidation of alcohols, n-propanol, 2-methoxy ethanol and 2-ethoxy ethanol by cerium (IV) in nitric acid leads to the formation of corresponding aldehydes. The reaction is first order with respect to Ce(IV). A Michaelis-Menten type kinetics is observed with respect to alcohols. The reaction is retarded by initial [Ce(IV)] with increase in concentration of oxidant. The reaction exhibits participation of 2 mole of cerium (IV) with 1 mole of alcohols. It has been concluded that Ce(IV)-dimer participate in the oxidation process and formation of free radical through complex ion formation in the nitric acid medium.
Physical, Thermal and Electrochemical Descant of Soil of Tirunelveli, India
Authors: P. Jeyaseeli P. Jeyaseeli , F Jeyamangalam F Jeyamangalam , D. Muthuraj D. Muthuraj , Durai S. C. Vella
Published: March 2022

To accomplish organic nourishment for the fleetly growing population in India can hold creating purposeful events at fostering the wise use of organic manures in crop productivity. Soil is one in all the foremost necessary physical factors dominant the flow and preservation of water, solutes, gases and biota in agriculture and natural environment. An understanding of physical condition of any soil is crucial for implementation of variable fields across the landscape. The field work is designed in South India of Tamil Nadu by planting the sweet corn at Karisalpatti village, Tirunelveli in 2018. It is gauged using single, double and triple manure combination of amendment at varied concentration to evaluates the physical properties of sandy loam soil. The field was set to go in randomised block style with 3 replications. A considerable enhancement in well being of soil was ascertained with reference to nourishing the convenience of physical steadiness using vermicompost manure. The increase in porosity has been attributed to extend the amount of pores within the soil. The physical changes of soil due to the time and temperature was assistance by thermo gravimetric and differential thermal methodology. Fourier transform infrared spectroscopy confirms the presence of organic mineral inside the soil. UV-Diffuse reflectance spectroscopy works out the structure and colourizes the sandy soil. Characterize the electrochemical system of soil using Cyclic Voltammeter spectroscopy. The result shows that thanks to the addition of organic manure there's robust OH bond absorption and stumps up high yield contribution to corn crop.
Mid-term improvement of cognitive performance after total hip arthroplasty in patients with osteoarthritis of the hip
Authors: Strahl André , Kazim Murteza Ali , Kattwinkel Nils , Hauskeller Wiebke , Moritz Steffen , Arlt Sönke , Niemeier Andreas
Published: March 2022

Aims

The aim of this study was to determine whether total hip arthroplasty (THA) for chronic hip pain due to unilateral primary osteoarthritis (OA) has a beneficial effect on cognitive performance.

Methods

A prospective cohort study was conducted with 101 patients with end-stage hip OA scheduled for THA (mean age 67.4 years (SD 9.5), 51.5% female (n = 52)). Patients were assessed at baseline as well as after three and months. Primary outcome was cognitive performance measured by d2 Test of Attention at six months, Trail Making Test (TMT), FAS-test, Rivermead Behavioural Memory Test (RBMT; story recall subtest), and Rey-Osterrieth Complex Figure Test (ROCF). The improvement of cognitive performance was analyzed using repeated measures analysis of variance.

Results

At six months, there was significant improvement in attention, working speed and concentration (d2-test; p < 0.001), visual construction and visual memory (ROCF; p < 0.001), semantic memory (FAS-test; p = 0.009), verbal episodic memory (RBMT; immediate recall p = 0.023, delayed recall p = 0.026), as well as pain (p < 0.001) with small to large effect sizes. Attention, concentration, and visual as well as verbal episodic memory improved significantly with medium effect sizes over η2partial= 0.06. In these cognitive domains the within-group difference exceeded the minimum clinically important difference.

Conclusion

THA is associated with clinically relevant postoperative improvement in the cognitive functions of attention, concentration, and memory. These data support the concept of a broad interaction of arthroplasty with central nervous system function. Cite this article: Bone Joint J 2022;104-B(3):331–340.
High revision rates following repeat septic revision after failed one-stage exchange for periprosthetic joint infection in total knee arthroplasty
Authors: Neufeld Michael E. , Liechti Emanuel F. , Soto Fernando , Linke Philip , Busch Sophia-Marlene , Gehrke Thorsten , Citak Mustafa
Published: March 2022

Aims

The outcome of repeat septic revision after a failed one-stage exchange for periprosthetic joint infection (PJI) in total knee arthroplasty (TKA) remains unknown. The aim of this study was to report the infection-free and all-cause revision-free survival of repeat septic revision after a failed one-stage exchange, and to determine whether the Musculoskeletal Infection Society (MSIS) stage is associated with subsequent infection-related failure.

Methods

We retrospectively reviewed all repeat septic revision TKAs which were undertaken after a failed one-stage exchange between 2004 and 2017. A total of 33 repeat septic revisions (29 one-stage and four two-stage) met the inclusion criteria. The mean follow-up from repeat septic revision was 68.2 months (8.0 months to 16.1 years). The proportion of patients who had a subsequent infection-related failure and all-cause revision was reported and Kaplan-Meier survival for these endpoints was determined. Patients were categorized according to the MSIS staging system, and the association with subsequent infection was analyzed.

Results

At the most recent follow-up, 17 repeat septic revisions (52%) had a subsequent infection-related failure and the five-year infection-free survival was 59% (95% confidence interval (CI) 39 to 74). A total of 19 underwent a subsequent all-cause revision (58%) and the five-year all-cause revision-free survival was 47% (95% CI 28 to 64). The most common indication for the first subsequent aseptic revision was loosening. The MSIS stage of the host status (p = 0.663) and limb status (p = 1.000) were not significantly associated with subsequent infection-related failure.

Conclusion

Repeat septic revision after a failed one-stage exchange TKA for PJI is associated with a high rate of subsequent infection-related failure and all-cause revision. Patients should be counselled appropriately to manage expectations. The host and limb status according to the MSIS staging system were not associated with subsequent infection-related failure. Cite this article: Bone Joint J 2022;104-B(3):386–393.
Critically high metal ion levels found in metal-on-metal modular hinged knee arthroplasty
Authors: Gramlich Yves , Hofmann Line , Kress Sandra , Ruckes Christian , Kemmerer Matthias , Klug Alexander , Hoffmann Reinhard , Kremer Michael
Published: March 2022

Aims

This study compared the cobalt and chromium serum ion concentration of patients treated with two different metal-on-metal (MoM) hinged total knee arthroplasty (TKA) systems, as well as a titanium nitride (TiN)-coated variant.

Methods

A total of 63 patients (65 implants) were treated using either a MoM-coated (n = 29) or TiN-coated (n = 7) hinged TKA (GenuX mobile bearing, MUTARS; Implantcast, Germany) versus the BPKS (Brehm, Germany) hinged TKA (n = 27), in which the weight placed on the MoM hinge is diffused through a polyethylene (PE) inlay, reducing the direct load on the MoM hinge. Serum cobalt and chromium ion concentrations were assessed after minimum follow-up of 12 months, as well as functional outcome and quality of life.

Results

No differences in mean age (69 years, 40 to 86), mean age adapted Charlson Comorbidity Index (3.1 (SD 1.4)), mean BMI (29.2 kg/m2 (SD 5.8)), or number of other implants were observed between groups. Significant improvements in outcome scores and pain levels were achieved for all groups, and there was no difference in quality of life (12-Item Short-Form Health Survey questionnaire (SF-12)). Mean cobalt and chromium ion levels were significantly higher for the GenuX versus the BPKS hinged TKA (GenuX vs BPKS: cobalt: 16.3 vs 9.4 µg/l; chromium: 9.5 vs 5.2 µg/l). The TiN-coated implants did not appear to confer improvement in the metal ion levels. Metal ion concentrations above 7 µg/l were detected in 81%(29/36) of GenuX patients versus 41% (11/27) in the BPKS group. No GenuX patients had normal levels under 2 µg/l, versus 22% of BPKS patients. No significant reduction in outcome scores was observed regardless of the metal ion levels, whereas higher work-related activity was correlated with higher chromium concentrations.

Conclusion

Hinged TKA, using MoM hinges, resulted in critically high cobalt and chromium ion concentrations. The BPKS hinged TKA showed significantly lower metal ion concentrations compared with the GenuX TKA. No benefits were observed using TiN coating. The different weightbearing mechanics might influence the wear of the component materials. Higher workloads and physical activity could influence chromium levels. Cite this article: Bone Joint J 2022;104-B(3):376–385.
Pelvic incidence significance relative to spinopelvic risk factors for total hip arthroplasty instability
Authors: Kleeman-Forsthuber Lindsay , Vigdorchik Jonathan M. , Pierrepont Jim W. , Dennis Douglas A.
Published: March 2022

Aims

Pelvic incidence (PI) is a position-independent spinopelvic parameter traditionally used by spinal surgeons to determine spinal alignment. Its relevance to the arthroplasty surgeon in assessing patient risk for total hip arthroplasty (THA) instability preoperatively is unclear. This study was undertaken to investigate the significance of PI relative to other spinopelvic parameter risk factors for instability to help guide its clinical application.

Methods

Retrospective analysis was performed of a multicentre THA database of 9,414 patients with preoperative imaging (dynamic spinopelvic radiographs and pelvic CT scans). Several spinopelvic parameter measurements were made by engineers using advanced software including sacral slope (SS), standing anterior pelvic plane tilt (APPT), spinopelvic tilt (SPT), lumbar lordosis (LL), and PI. Lumbar flexion (LF) was determined by change in LL between standing and flexed-seated lateral radiographs. Abnormal pelvic mobility was defined as ∆SPT ≥ 20° between standing and flexed-forward positions. Sagittal spinal deformity (SSD) was defined as PI-LL mismatch > 10°.

Results

PI showed a positive correlation with parameters of SS, SPT, and LL (r-value range 0.468 to 0.661). Patients with a higher PI value showed higher degrees of standing LL, likely as a compensatory measure to maintain sagittal spine balance. There was a positive correlation between LL and LF such that patients with less standing LL had decreased LF ( r = 0.49). Similarly, there was a positive correlation between increased SSD and decreased LF ( r = 0.54). PI in isolation did not show any significant correlation with lumbar ( r = 0.04) or pelvic mobility ( r = 0.02). The majority of patients (range 89.4% to 94.2%) had normal lumbar and pelvic mobility regardless of the PI value.

Conclusion

The PI value alone is not indicative of either spinal or pelvic mobility, and thus in isolation may not be a risk factor for THA instability. Patients with SSD had higher rates of spinopelvic stiffness, which may be the mechanism by which PI relates to THA instability risk, but further clinical studies are required. Cite this article: Bone Joint J 2022;104-B(3):352–358.
The outcome of subsequent revisions after primary total hip arthroplasty in 1,049 patients aged under 50 years
Authors: Kuijpers Martijn F. L. , Colo Ena , Schmitz Marloes W. J. L. , Hannink Gerjon , Rijnen Wim H. C. , Schreurs B. Willem
Published: March 2022

Aims

The aim of this study was to determine the outcome of all primary total hip arthroplasties (THAs) and their subsequent revision procedures in patients aged under 50 years performed at our institution.

Methods

All 1,049 primary THAs which were undertaken in 860 patients aged under 50 years between 1988 and 2018 in our tertiary care institution were included. We used cemented implants in both primary and revision surgery. Impaction bone grafting was used in patients with acetabular or femoral bone defects. Kaplan-Meier analyses were used to determine the survival of primary and revision THA with the endpoint of revision for any reason, and of revision for aseptic loosening.

Results

The mean age of the patients at the time of the initial THA was 38.6 years (SD 9.3). The mean follow-up of the THA was 8.7 years (2.0 to 31.5). The rate of survival for all primary THAs, acetabular components only, and femoral components only at 20 years’ follow-up with the endpoint of revision for any reason, was 66.7% (95% confidence interval (CI) 60.5 to 72.2), 69.1% (95% CI 63.0 to 74.4), and 83.2% (95% CI 78.1 to 87.3), respectively. A total of 138 revisions were performed. The mean age at the time of revision was 48.2 years (23 to 72). Survival of all subsequent revision procedures, revised acetabular, and revised femoral components at 15 years’ follow-up with the endpoint of revision for any reason was 70.3% (95% CI 56.1 to 80.7), 69.7% (95% CI 54.3 to 80.7), and 76.2% (95% CI 57.8 to 87.4), respectively. A Girdlestone excision arthroplasty was required in six of 860 patients (0.7%).

Conclusion

The long-term outcome of cemented primary and subsequent revision THA is promising in these young patients. We showed that our philosophy of using impaction bone grafting in patients with acetabular and femoral defects is a very suitable option when treating young patients. Surgeons should realize that knowledge of the outcome of subsequent revision surgery, which is inevitable in young patients, must be communicated to this group of patients prior to their initial THA. Cite this article: Bone Joint J 2022;104-B(3):368–375.
Survivorship, complications, and outcomes following distal femoral arthroplasty for non-neoplastic indications
Authors: Sobol Keenan Rhys , Fram Brianna R. , Strony John T. , Brown Scot A.
Published: March 2022

Aims

Endoprosthetic reconstruction with a distal femoral arthroplasty (DFA) can be used to treat distal femoral bone loss from oncological and non-oncological causes. This study reports the short-term implant survivorship, complications, and risk factors for patients who underwent DFA for non-neoplastic indications.

Methods

We performed a retrospective review of 75 patients from a single institution who underwent DFA for non-neoplastic indications, including aseptic loosening or mechanical failure of a previous prosthesis (n = 25), periprosthetic joint infection (PJI) (n = 23), and native or periprosthetic distal femur fracture or nonunion (n = 27). Patients with less than 24 months’ follow-up were excluded. We collected patient demographic data, complications, and reoperations. Reoperation for implant failure was used to calculate implant survivorship.

Results

Overall one- and five-year implant survivorship was 87% and 76%, respectively. By indication for DFA, mechanical failure had one- and five-year implant survivorship of 92% and 68%, PJI of 91% and 72%, and distal femur fracture/nonunion of 78% and 70% (p = 0.618). A total of 37 patients (49%) experienced complications and 27 patients (36%) required one or more reoperation. PJI (n = 16, 21%), aseptic loosening (n = 9, 12%), and wound complications (n = 8, 11%) were the most common complications. Component revision (n = 10, 13.3%) and single-stage exchange for PJI (n = 9, 12.0 %) were the most common reoperations. Only younger age was significantly associated with increased complications (mean 67 years (SD 9.1)) with complication vs 71 years (SD 9.9) without complication; p = 0.048).

Conclusion

DFA is a viable option for distal femoral bone loss from a range of non-oncological causes, demonstrating acceptable short-term survivorship but with high overall complication rates. Cite this article: Bone Jt Open 2022;3(3):173–181.
The creative co-design of low back pain education resources
Authors: Webber Richard , Partridge Rebecca , Grindell Cheryl
Published: March 2022

Background:

Evidence-based guidelines provide clinicians with best practice recommendations but not the means to implement them. Although co-design is increasingly promoted as a way to improve implementation there is frequently insufficient detail provided to understand its contribution. The presented case study addresses this by providing a detailed account of how a specific co-design approach contributed to an improving back pain education project in line with national guidance.

Aim:

The aim was to use creative co-design to produce prototype evidence-based back pain educational resources that were sensitive to context.

Objectives:

Assemble a group of relevant stakeholders for a series of workshops.

Use creative activities that encourage divergent and convergent thinking to iteratively understand the problem and develop prototype solutions.

Thematically analyse outputs of each workshop to determine content of subsequent workshops.

Present a final prototype ready for implementation.

Key conclusions:

This approach produced an innovative system of thematically linked back pain educational resources that were contextually sensitive, evidence-based and ready for implementation.

Research knowledge was successfully blended with stakeholder experiential knowledge.

The creative methods helped diverse stakeholders develop trusting relationships and ensured everyone’s experiences and ideas were included.

The process of co-creation and the objects created had vital roles in surfacing and understanding stakeholder knowledge, promoting innovation and facilitating implementation.

The design process facilitated an evolving understanding of a complex problem alongside prototype development.

It is recommended that these methods be considered by other project teams.
Universal Credit and the invalidation of mental health problems: claimant and Jobcentre Plus staff experiences
Authors: Wright Sharon , Robertson Laura , Stewart Alasdair B. R.
Published: March 2022

Moving disabled people ‘off benefits and into work’ has been an explicit aim of work-first welfare reform since 2008, increasingly punitively since 2010. The aim of this article is to demonstrate, for the first time, how Universal Credit (UC) fits with and intensifies that strategy. Empirical data from 28 in-depth interviews with 19 claimants (nine were interviewed twice) and three focus groups with 23 Jobcentre staff show how UC full service applies mainstream job search conditionality to people with mental health problems. Ongoing fear of sanctions, financial hardship, surveillance and social isolation relating to digital design had adverse impacts, including for those without previous mental health problems.
Leveraging joint allocation of multidimensional resources for distributed task assignment
Authors: Li Jialong , Hua Nan , Zhu Kangqi , Zhao Chen , Pan Guanqin , Li Yanhe , Zheng Xiaoping , Zhou Bingkun
Published: March 2022

Edge computing has changed the landscape of telecommunication networks. Different from cloud computing in which thousands of servers are centralized in a remote site, computation and storage resources are deployed at the network edge in edge computing, reducing the end-to-end latency and the amount of transmitting data in metro/backbone networks significantly. Due to the limited resource capacity in a single edge node and the requirements of distributed applications, some applications are supposed to be decomposed into multiple interdependent tasks and executed in distributed resource-constrained nodes. Assigning tasks to geographically distributed edge nodes is quite challenging because of the allocation of multidimensional resources (i.e., computation, storage, and transmission) as well as constraints of the interdependency between different tasks. Strategies that take only one factor into account for optimization will cause improper task assignments, leading to higher end-to-end latency and lower resource utilization efficiency. To solve this problem, we formulate a mathematical model aiming at minimizing the job completion time by jointly considering the availability of multidimensional resources and the interdependency among different tasks. We obtain optimal results in small topology by using optimization software that validates the correctness of the proposed mathematical model. Furthermore, we analyze the complexity and design of a practical algorithm by narrowing the searching space in large-scale topology. Simulation results present its effectiveness over greedy algorithms. Finally, we conduct a proof-of-concept experiment to validate the feasibility of the proposed strategy.
Optical elliptic breathers in isotropic nonlocal nonlinear media
Authors: Zhang Huicong , Zhou Tao , Shou Qian , Guo Qi
Published: March 2022

We investigate the propagation dynamics of elliptic Gaussian breathers without and with orbital angular momentum (OAM) in thermal nonlocal nonlinear media with both linear and nonlinear isotropy. The beamwidths and intensity of the elliptic breather without OAM, and the beamwidths and rotation angle of the elliptic breather with the critical OAM are analytically discussed in details. In experiment, the OAM-free elliptic beam is observed to oscillate and cannot form an elliptic soliton for any input power. By contrast, the elliptic beam carrying the critical OAM can keep its ellipticity changeless during the propagation and evolve into a spiralling elliptic soliton at the critical power. Specifically, in the vicinity of the critical power, the rotation angle of the spiralling elliptic beam can be controlled linearly by the input power and exceed π/2, while its beamwidths and ellipticity remain unchanged. Such a power-controllable, profile-preserving spiralling elliptic beam may provide potential applications in all-optical manipulation.
Depth-resolved transverse-plane motion tracking with configurable measurement features via optical coherence tomography
Authors: Ni Guangming , Wu Renxiong , Zhong Junming , Liu Yong
Published: March 2022

Optical coherence tomography (OCT), a promising noninvasive bioimaging technique, has become one of the most successful optical technologies implemented in medicine and clinical practice. Here we report a novel technique of depth-resolved transverse-plane motion tracking with configurable measurement features via optical coherence tomography, termed OCT-MT. Based on OCT circular scanning combined with speckle spatial oversampling, the OCT-MT technique can perform depth-resolved transverse-plane motion tracking. Benefitting from the optical interference and depth-resolved feature, the proposed OCT-MT can reduce the requirements on the input power of the irradiation signal and the surface reflectivity and roughness of the target, when performing motion tracking. Furthermore, OCT-MT can conduct such kind of motion tracking with configurable measurement ranges and resolutions by configuring A-line number per scanning circle, circular scanning radius, and A-line scanning time. The proposed OCT-MT technique may expand the ability of motion tracking for OCT in addition to imaging.
Development of hard masks for reactive ion beam angled etching of diamond
Authors: Chia Cleaven , Machielse Bartholomeus , Shams-Ansari Amirhassan , Lončar Marko
Published: March 2022

Diamond offers good optical properties and hosts bright color centers with long spin coherence times. Recent advances in angled-etching of diamond, specifically with reactive ion beam angled etching (RIBAE), have led to successful demonstration of quantum photonic devices operating at visible wavelengths. However, larger devices operating at telecommunication wavelengths have been difficult to fabricate due to the increased mask erosion, arising from the increased size of devices requiring longer etch times. We evaluated different mask materials for RIBAE of diamond photonic crystal nanobeams and waveguides, and how their thickness, selectivity, aspect ratio and sidewall smoothness affected the resultant etch profiles and optical performance. We found that a thick hydrogen silesquioxane (HSQ) layer on a thin alumina adhesion layer provided the best etch profile and optical performance. The techniques explored in this work can also be adapted to other bulk materials that are not available heteroepitaxially or as thin films-on-insulator.
Experimental quantification of dynamical coherence via entangling two qubits
Authors: He Ren-Dong , Wu Kang-Da , Xiang Guo-Yong , Li Chuan-Feng , Guo Guang-Can
Published: March 2022

Coherence and entanglement are both the fundamental properties which quantify the degree of nonclassicality possessed in a quantum state. Recently coherence and entanglement are considered as a dynamical resource where the nonclassicality is strongly related to the amount of the static resources which can be generated in a quantum process. In [Phys. Rev. Lett. 125, 130401 (2020)10.1103/PhysRevLett.125.130401], for the first time, the authors study the interconvertability of these two kinds of dynamical resources. Here, we demonstrate this resource conversion in an all optical setup, and successfully observe the dynamical resource conversion. The experimental observation prove the ability of manipulating dynamical resource within current quantum photonic technologies.
Self-calibrated general model-based wavefront sensorless adaptive optics for both point-like and extended objects
Authors: Ren Hongxi , Dong Bing
Published: March 2022

The deformable mirror (DM) in conventional model-based wavefront sensorless adaptive optics (WFSless AO) must be calibrated in advance by an additional WFS in order to precisely generate predetermined bias modes with known amplitudes. Although the WFS is unnecessary during correction, it will increase system complexity and may be unavailable in real applications. In this paper, the model-based WFSless AO algorithms, either for point-like or extended objects, are generalized to a unified form and the calibration problem comes down to the measurement of a Gram matrix. We proposed a novel self-calibration procedure to obtain the Gram matrix without using a WFS. The calibrated Gram matrix can be used directly for simultaneous correction if using the influence functions of DM as the bias modes, requiring N+1 images to correct N modes. Alternatively, orthogonal or gradient-orthogonal mirror modes obtained from the eigenvectors of the Gram matrix can be used as the modal basis to implement independent sequential correction that requires 2N images to correct N modes. Simulations and experiments have been done to verify the feasibility of proposed self-calibration and correction methods for both point-like and extended objects in a WFSless AO system.
Modulated pattern scanning microscopy
Authors: Qiu Yuxuan , Huang Yuran , Liu Xin , Zhang Yusen , Hao Xiang , Kuang Cuifang , Liu Xu
Published: March 2022

In confocal microscopy, the effective optical transfer function (OTFeff) with Gaussian plane wave illumination covers very few high-frequency components, which prohibits further improvement of the resolution. We propose modulated pattern scanning microscopy (MPSM) to achieve super-resolution imaging. In MPSM, the phase of the illumination beam is modulated to reassign the OTFeff in the Fourier domain. The phase mask is designed using an optimization algorithm to obtain the fluorescence emission pattern with rich high-frequency components. Then, the postprocessing algorithms are adapted to retrieve the super-resolved images from the modulated recordings. Simulation and experiment demonstrate that MPSM increases the resolution approximately 1.3 times better than confocal microscopy. Compared with conventional deconvolution, MPSM exhibits a higher signal-to-noise ratio.
Intense optical parametric amplification in dispersion-engineered nanophotonic lithium niobate waveguides
Authors: Ledezma Luis , Sekine Ryoto , Guo Qiushi , Nehra Rajveer , Jahani Saman , Marandi Alireza
Published: March 2022

Strong amplification in integrated photonics is one of the most desired optical functionalities for computing, communications, sensing, and quantum information processing. Semiconductor gain and cubic nonlinearities, such as four-wave mixing and stimulated Raman and Brillouin scattering, have been among the most studied amplification mechanisms on chip. Alternatively, material platforms with strong quadratic nonlinearities promise numerous advantages with respect to gain and bandwidth, among which nanophotonic lithium niobate is one of the most promising candidates. Here, we combine quasi-phase matching with dispersion engineering in nanophotonic lithium niobate waveguides and achieve intense optical parametric amplification. We measure a broadband phase-sensitive on-chip amplification larger than 50 dB/cm in a 6-mm-long waveguide. We further confirm high gain operation in the degenerate and nondegenerate regimes by amplifying vacuum fluctuations to macroscopic levels, with on-chip gains exceeding 100 dB/cm over 600 nm of bandwidth around 2 µm. Our results unlock new possibilities for on-chip few-cycle nonlinear optics, mid-infrared photonics, and quantum photonics.
Linkages between social and financial performance: Evidence from Sub-Saharan Africa microfinance institutions
Authors: Fadikpe Amidou Ayinla Akangbe , Danquah Richard , Aidoo Mohammed , Chomen Dejene Adugna , Yankey Richard , Dongmei Xie
Published: March 2022

Microfinance Institutions provide financial services to low-income clients and the poor who are excluded from formal financial institutions. Hence, the sustainability of microfinance institutions (MFIs) remains essential. This study examines the relationship between social and financial performance and whether there is a trade-off between both objectives after the 2008 global financial crisis. The study used 735 observations from 105 Microfinance Institutions across 26 countries in Sub-Saharan Africa from 2011 to 2017 and employed the Generalized Method of Moment and Seeming Unrelated Regression for the analyses. The results indicate that increasing the number of customers [breadth of outreach increased the financial performance (return on equity)]. The result also showed that the Percentage of Female Borrowers contributes to the sustainability of Microfinance Institutions due to their higher loan repayment rate than males. In addition, our results document a trade-off between the Depth of Outreach and Operational Self-Sustainability among Microfinance Institutions. The study recommends the following: 1) Microfinance institutions should purposefully increase credit facilities extended to female borrowers since that will make them sustainable. 2) Governments in Sub-Saharan African countries should provide increased financial support in the form of subsidies and tax holidays to Microfinance Institutions operating in very deprived areas, and 3) Management of Microfinance institutions on the continent should regularly re-train and upgrade their staff capacity to effectively assess and manage customers before and after extending credit to them to sustain the industry.