cssi/SciSciGPT-SciSciNet huggingface dataset:
Haptic Assembly Using Skeletal Densities and Fourier Transforms

Haptic-assisted virtual assembly and prototyping has seen significant attention over the past two decades. However, in spite of the appealing prospects, its adoption has been slower than expected. We identify the main roadblocks as the inherent geometric complexities faced when assembling objects of arbitrary shape, and the computation time limitation imposed by the notorious 1 kHz haptic refresh rate. We addressed the first problem in a recent work by introducing a generic energy model for geometric guidance and constraints between features of arbitrary shape. In the present work, we address the second challenge by leveraging Fourier transforms to compute the constraint forces and torques. Our new concept of “geometric energy” field is computed automatically from a cross-correlation of “skeletal densities” in the frequency domain, and serves as a generalization of the manually specified virtual fixtures or heuristically identified mating constraints proposed in the literature. The formulation of the energy field as a convolution enables efficient computation using fast Fourier transforms (FFTs) on the graphics processing unit (GPU). We show that our method is effective for low-clearance assembly of objects of arbitrary geometric and syntactic complexity.
Dennis Brutus (1924-2009): An Appreciation

The death of Dennis Brutus sees the passing of South Africa's most internationally renowned poet since Roy Campbell. There may be no other point of comparison between the two men, and their international renown probably says more about international readers and the business of poetry publishing than it does about the quality of their work or the qualities of their character, but it points to one of the biggest ironies about Brutus's life and career : that this most intensely South African poet felt that he had not really got the respect he deserved in his own country. Although it seems fitting that after his long exile he will be buried in the land that he loved, even at his death he was at political odds too with the national regime whose policies he viewed as complicit with a global economic system that replicated apartheid injustice on an international scale.
Infant Mortality in West Africa: The Role of Climate

Although infant mortality has decreased in the world in recent years, countries in Sub-Saharan Africa are still struggling with high prevalence of infant deaths. Using Demographic and Health Survey (DHS) and high resolution rainfall and temperature estimates, we investigate how weather conditions could affect an infant’s survival in Mali. Applying survival analysis, we find that high rainfall amount during the growing season and heat stress during the dry season negatively affect an infant’s survival in rural areas, but not in urban areas. Furthermore, there are significant prenatal weather effects on infants, suggesting that pregnant mothers’ exposure to heat, disease or malnutrition could negatively affect child health. The findings suggest that healthcare in rural communities should take a priority in public health policy debates in mitigating infant deaths in the future.
Payment scheme self-selection in the credence goods market: An experimental study

Abstract Given heterogeneity in expert behavior across payment schemes in credence goods markets, it is important to understand the consequences of payment scheme selection on market outcomes. To study the effect that expert payment selection has on customer well-being, we recruited subjects to participate in a real-effort credence goods laboratory game. Experts were either randomly assigned or faced with the choice of three payment schemes: fee-for-service, salary, and capitation. We found that when experts selected fee-for-service payment customers experience significantly worse outcomes than when experts were randomly assigned to fee-for-service. In contrast, whether experts selected or were randomly assigned to salary payment, customer outcomes did not change.
FEMORAL HEAD MATERIALS: NO DIFFERENCE IN OUTCOMES – OPPOSES

Recent issues related to trunionosis have created a new paradigm in choosing femoral head material in total hip arthroplasty. While many consider highly-crosslinked polyethylene (XLPE) to be the gold standard currently in acetabular liner bearing surface, the debate remains whether metal or ceramic heads are best paired with XLPE. Wear characteristics are similar within an order of magnitude when comparing cobalt chrome femoral heads with ceramic when used in combination with XLPE. Therefore, discernable differences between the two femoral head materials with respect to outcomes would be the result of other biomechanical factors. Notably the fretting and corrosion of metal heads at the modular taper of femoral components is a serious concern and represents a significant deterrent when considering this material. The fretting corrosion that occurs with metal femoral heads has recently been well documented in multiple reports, and can be associated with adverse local tissue reactions necessitating revision hip arthroplasty. Frictional torque has recently been implicated in taper corrosion at modular junctions. In a recent simulated in vivo study, large diameter CoCr femoral heads were associated with increased frictional torque compared to smaller metal heads, supporting recent taper corrosion retrieval studies. In one recent series, a 1.1% incidence of head-neck taper corrosion with a metal head was reported and the authors recommended use of ceramic femoral heads. The notable downside of ceramic femoral heads is the implant cost and potential for fracture. However, the incidence of femoral head fracture with the newer mixed delta ceramic heads is exceptionally low and infrequent (rate 1.7 per 100,000). Furthermore, the incidence of taper corrosion is negligible with ceramic heads, making it the bearing couple of choice among many surgeons in combination with XLPE.
Institutional Pressures and Organizational Characteristics: The Case of Polluting Emissions and the Toxics Release Inventory

This article develops a model that demonstrates how organizational characteristics moderate institutional pressures on firms that report annually to the Toxics Release Inventory. In terms of institutional pressures, market forces, non-market forces and regulatory demands influence environmental practices at the plant level. Organizational characteristics of the firm, including firm size, competitive position and degree of internationalization moderate these influences, leading to a firm’s corporate environmental performance. The article finds that firms may voluntarily over-comply with the existing regulation when such action aligns with existing corporate strategies and culture, reducing the possibility of stricter regulation and enhancing a socially responsible reputation.JEL: Q52, Q58, H32, M14, M21
Evaluation of Weekly Paclitaxel, Carboplatin, and Cetuximab in Head and Neck Cancer Patients With Incurable Disease

Weekly paclitaxel, carboplatin, and cetuximab (PCC) has been found to be efficacious and well-tolerated in patients with squamous cell carcinoma of the head and neck (SCCHN) with good performance status (PS) when used as induction chemotherapy. Use of PCC in incurable SCCHN in patients with poor PS or in a non-induction setting is an area which warrants further evaluation. Current recommendations for incurable disease consist of a platinum-based regimen with fluorouracil and cetuximab. Studied in patients with PS of 0 to 1, the fluorouracil-based regimens were associated with significant toxicities. Therefore, weekly PCC may offer an appealing, less toxic alternative for incurable patients with poor PS. This retrospective analysis evaluated 41 patients with very advanced or metastatic head and neck cancer who had received PCC (paclitaxel 80 mg/m2, carboplatin AUC 2, and a cetuximab 400 mg/m2 loading dose, followed by 250 mg/m2 weekly) for up to 6 cycles between April 2008 and September 2014. Maximal response achieved and progression-free survival (PFS), as well as dose intensity and adverse effects, were evaluated. Of the 41 patients evaluated, baseline PS ranged as follows: PS of 2 (41 %), PS of 1 (54 %), and PS of 0 (5 %). Patients received 2 to 6 cycles, averaging 4 cycles. Thirty-one patients (76 %) required treatment to be held, delayed or dose reduced, most commonly for hematologic toxicities. Grades 3/4 neutropenia occurred in 16 patients (39 %), grades 1/2 neutropenia in 12 patients (29 %), with grades 3/4 thrombocytopenia in 1 patient (2 %), and grades 1/2 thrombocytopenia in 2 patients (4 %). No patients developed febrile neutropenia or required hospitalization due to treatment. Partial radiographic response occurred in 15 patients (37 %), complete radiographic response in 2 patients (5 %), stable disease in 14 patients (34 %), and progression in 8 patients (20 %). PFS ranged from 1.6 to 45 months, with a median duration of 4.6 months, and median overall survival of 5.25 months. Analysis indicates that use of weekly PCC appears to be an effective and well-tolerated treatment option for patients with incurable squamous cell carcinoma of the head and neck, specifically with PS of 0 to 2.
Data colonialism through accumulation by dispossession: New metaphors for daily data

In recent years, much has been written on ‘big data’ in both the popular and academic press. After the hubristic declaration of the ‘end of theory’ more nuanced arguments have emerged, suggesting that increasingly pervasive data collection and quantification may have significant implications for the social sciences, even if the social, scientific, political, and economic agendas behind big data are less new than they are often portrayed. Compared to the boosterish tone of much of its press, academic critiques of big data have been relatively muted, often focusing on the continued importance of more traditional forms of domain knowledge and expertise. Indeed, many academic responses to big data enthusiastically celebrate the availability of new data sources and the potential for new insights and perspectives they may enable. Undermining many of these critiques is a lack of attention to the role of technology in society, particularly with respect to the labor process, the continued extension of labor relati...
From invariant checking to invariant inference using randomized search

We describe a general framework c2i for generating an invariant inference procedure from an invariant checking procedure. Given a checker and a language of possible invariants, c2i generates an inference procedure that iteratively invokes two phases. The search phase uses randomized search to discover candidate invariants and the validate phase uses the checker to either prove or refute that the candidate is an actual invariant. To demonstrate the applicability of c2i , we use it to generate inference procedures that prove safety properties of numerical programs, prove non-termination of numerical programs, prove functional specifications of array manipulating programs, prove safety properties of string manipulating programs, and prove functional specifications of heap manipulating programs that use linked list data structures.
Nonlinearity and the Study of Organizations

The article looks at a study which explores organizational behavior for nonlinear relationships. The use of linear theories and statistics within research design is discussed. Examples of nonlinari...
Copper-Catalyzed Etherification of Arene C–H Bonds

A method for direct, auxiliary-assisted alkoxylation and phenoxylation of β-sp2 C–H bonds of benzoic acid derivatives and γ-sp2 C–H bonds of amine derivatives is reported. The reaction employs (CuOH)2CO3 catalyst, air as an oxidant, phenol or alcohol coupling partner, DMF, pyridine, or DMPU solvent, and K2CO3, tetramethylguanidine, or K3PO4 base at 70–130 °C.
Impedance model-based SSR analysis for TCSC compensated type-3 wind energy delivery systems

This paper employs impedance model-based frequency domain analysis to detect subsynchronous resonances (SSRs) in Type-3 wind farms with thyristor-controlled series capacitor (TCSC). The contributions of this paper are 1)the derivation of dynamic phasor-based TCSC impedance model and 2)the application of such an impedance model in Type-3 wind energy systems for SSR analysis. Impedance models for TCSC with constant firing angle control and impedance control are derived in this paper. With the derived impedance models, Nyquist stability criterion is applied to compare SSR stability in Type-3 wind farm with TCSC or with fixed capacitor compensation. This paper employs analytical models to demonstrate TCSCs capability in avoiding SSR in Type-3 wind generator interconnection systems. The analytical results obtained through impedance models are validated by detail model-based (with thyristor switch-modeled) time-domain simulation in MATLAB/SimPowerSystems.
Solar Sailing Kinetic Energy Interceptor (KEI) Mission for Impacting and Deflecting Near-Earth Asteroids

A solar sailing mission architecture, which requires a t least ten 160-m, 300-kg solar sail spacecraft with a characteristic acceleration of 0.5 mm/sqs, is proposed as a realistic near- term option for mitigating the threat posed by near-Earth asteroids (NEAs). Its mission feasibility is demonstrated for a fictional asteroid mitigation problem created by AIAA. This problem assumes that a 200-m asteroid, designated 2004WR, was detected on July 4, 2004, and that the expected impact will occur on January 14, 2015. The solar sailing phase of the proposed mission for the AIAA asteroid mitigation problem is comprised of the initial cruise phase from 1 AU t o 0.25 AU (1.5 years), the cranking orbit phase (3.5 years), and the retrograde orbit phase (1 year) prior to impacting the target asteroid at its perihelion (0.75 AU from the sun) on January 1, 2012. The proposed mission will require at least ten kinetic energy interceptor (KEI) solar sail spacecraft. Each KEI sailcraft consists of a 160- m, 150-kg solar sail and a 150-kg microsatellite impactor. The impactor is to be separated from a large solar sail prior to impacting the 200-m target asteroid at its perihelion. Each 150-kg microsatellite impactor, with a relative impact velocity of at least 70 km/s, will cause a conservatively estimated AV of 0.3 cm/s in the trajectory of the 200-m target asteroid, due largely to the impulsive effect of material ejected from the newly-formed crater. The deflection caused by a single impactor will increase the Earth-miss-distance by 0.45Re (where Re denotes the Earth radius of 6,378 km). Therefore, at least ten KEI sailcraft will be required for consecutive impacts, but probably without causing fragmentation, to increase the total Earth-miss-distance by 4.5Re. This miss-distance increase of 29,000 km is outside of a typical uncertainty/error of about 10,000 km in predicting the Earth-miss- distance. A conventional Delta I1 2925 launch vehicle is capable of injecting at least two KEI sailcraft into an Earth escaping orbit. A 40-m solar sail is currently being developed by NASA and industries for a possible flight validation experiment within 10 years, and a 160-m solar sail is expected to be available within 20 years.
Unexpected Actinyl Cation-Directed Structural Variation in Neptunyl(VI) A-Type Tri-lacunary Heteropolyoxotungstate Complexes

A-type tri-lacunary heteropolyoxotungstate anions (e.g., [PW9O34]9–, [AsW9O34]9–, [SiW9O34]10–, and [GeW9O34]10–) are multidentate oxygen donor ligands that readily form sandwich complexes with actinyl cations ({UO2}2+, {NpO2}+, {NpO2}2+, and {PuO2}2+) in near-neutral/slightly alkaline aqueous solutions. Two or three actinyl cations are sandwiched between two tri-lacunary anions, with additional cations (Na+, K+, or NH4+) also often held within the cluster. Studies thus far have indicated that it is these additional +1 cations, rather than the specific actinyl cation, that direct the structural variation in the complexes formed. We now report the structural characterization of the neptunyl(VI) cluster complex (NH4)13[Na(NpO2)2(A-α-PW9O34)2]·12H2O. The anion in this complex, [Na(NpO2)2(PW9O34)2]13–, contains one Na+ cation and two {NpO2}2+ cations held between two [PW9O34]9– anions, with an additional partial occupancy NH4+ or {NpO2}2+ cation also present. In the analogous uranium(VI) system, under similar...
Economic Analysis of Real-Time Large-Scale PEVs Network Power Flow Control Algorithm With the Consideration of V2G Services

In this paper, the economic analysis of a real-time power flow control algorithm for charging a large-scale plug-in electric vehicles (PEVs) network is proposed. Such a system is in an urban area power system with optimized renewable energy resources in South Florida. In this model, the PEVs charging rates are controlled by a central aggregator through wireless communication. To limit the impact of the PEVs' charging to the utility grid, while optimizing the scheduling of vehicle-to-grid (V2G) frequency regulation services, a V2G intelligent power flow management algorithm based on fuzzy logic control was developed. The smart charging system will improve the power system stability and robustness while bringing benefits to the utility ac grid, the PEVs network, and its customers. An economic analysis model was built with the consideration of the battery degradation and capital cost. The proposed smart charging algorithm was tested with a 50 000 PEVs network model. The simulation results show the effectiveness and economic value of the proposed model.
Phase-selective chemical extraction of selenium and sulfur from nanoscale metal chalcogenides: a general strategy for synthesis, purification, and phase targeting.

Controlling the composition and phase formation of bulk and nanoscale solids underpins efforts to control physical properties. Here, we introduce a powerful new chemical pathway that facilitates composition-tunable synthesis, post-synthesis purification, and precise phase targeting in metal chalcogenide systems. When metal selenides and sulfides react with trioctylphosphine (TOP) at temperatures that range from 65 to 270 °C, selenium and sulfur are selectively extracted to produce the most metal-rich chalcogenide that is stable in a particular binary system. This general approach is demonstrated for SnSe2, FeS2, NiSe2, and CoSe2, which convert to SnSe, FeS, Ni3Se2, and Co9Se8, respectively. In-depth studies of the Fe−Se system highlight the precise phase targeting and purification that is achievable, with PbO-type FeSe (the most metal-rich stable Fe−Se phase) forming exclusively when other Fe−Se phases, including mixtures, react with TOP. This chemistry also represents a new template-based nanoparticle “c...
Codoping in SnTe: Enhancement of Thermoelectric Performance through Synergy of Resonance Levels and Band Convergence

We report a significant enhancement of the thermoelectric performance of p-type SnTe over a broad temperature plateau with a peak ZT value of ∼1.4 at 923 K through In/Cd codoping and a CdS nanostructuring approach. Indium and cadmium play different but complementary roles in modifying the valence band structure of SnTe. Specifically, In-doping introduces resonant levels inside the valence bands, leading to a considerably improved Seebeck coefficient at low temperature. Cd-doping, however, increases the Seebeck coefficient of SnTe remarkably in the mid- to high-temperature region via a convergence of the light and heavy hole bands and an enlargement of the band gap. Combining the two dopants in SnTe yields enhanced Seebeck coefficient and power factor over a wide temperature range due to the synergy of resonance levels and valence band convergence, as demonstrated by the Pisarenko plot and supported by first-principles band structure calculations. Moreover, these codoped samples can be hierarchically struc...
Sequential rhodium-, silver-, and gold-catalyzed synthesis of fused dihydrofurans

A triple cascade process was developed for the rapid synthesis of polycyclic benzo-fused dihydrofurans. The first step is a rhodium-catalyzed cyclopropanation of α-aryldiazoketones with alkenes. This is followed by a silver-catalyzed ring expansion to dihydrofurans, which then undergo a gold-catalyzed cyclization to form benzo-fused dihydrofurans.
Modeling the Effect of Dissolved Hydrogen Sulfide on Mg2+-water Complex on Dolomite {104} Surfaces

The key kinetic barrier to dolomite formation is related to the surface Mg2+–H2O complex, which hinders binding of surface Mg2+ ions to the CO32– ions in solution. It has been proposed that this reaction can be catalyzed by dissolved hydrogen sulfide. To characterize the role of dissolved hydrogen sulfide in the dehydration of surface Mg2+ ions, ab initio simulations based on density functional theory (DFT) were carried out to study the thermodynamics of competitive adsorption of hydrogen sulfide and water on dolomite (104) surfaces from solution. We find that water is thermodynamically more stable on the surface with the difference in adsorption energy of −13.6 kJ/mol (in vacuum) and −12.8 kJ/mol (in aqueous solution). However, aqueous hydrogen sulfide adsorbed on the surface increases the Mg2+–H2O distances on the surrounding surface sites. Two possible mechanisms were proposed for the catalytic effects of adsorbed hydrogen sulfide on the anhydrous Ca–Mg carbonate crystallization at low temperature.
“Truthiness” and Second-Level Agenda Setting: Satire News and Its Influence on Perceptions of Television News Credibility

This study examined the impact of satire news programs on perceptions of media credibility. Using second-level agenda setting as a theoretical framework, the results of this mixed-methods study show that negative portrayals of television news on these satire news shows make salient certain negative attributes that match viewers’ perceptions of credibility. A survey (N = 650) found that Daily Show/Colbert Report viewers had less positive views about the credibility of television news programs, while content analysis (N = 401) of 4 weeks of episodes of The Daily Show and The Colbert Report reflected the results of the survey, showing that television news programs, particularly those on cable, were more frequently portrayed negatively and made the target of jokes. The analysis shows television news is a frequent target of these satire shows’ criticisms and these shows’ negative attributes are made salient, which is reflected in the survey respondents’ low credibility scores for this medium.
Bidentate, monoanionic auxiliary-directed functionalization of carbon-hydrogen bonds.

ConspectusIn recent years, carbon–hydrogen bond functionalization has evolved from an organometallic curiosity to a tool used in mainstream applications in the synthesis of complex natural products and drugs. The use of C–H bonds as a transformable functional group is advantageous because these bonds are the most abundant functionality in organic molecules. One-step conversion of these bonds to the desired functionality shortens synthetic pathways, saving reagents, solvents, and labor. Less chemical waste is generated as well, showing that this chemistry is environmentally beneficial. This Account describes the development and use of bidentate, monoanionic auxiliaries for transition-metal-catalyzed C–H bond functionalization reactions. The chemistry was initially developed to overcome the limitations with palladium-catalyzed C–H bond functionalization assisted by monodentate directing groups. By the use of electron-rich bidentate directing groups, functionalization of unactivated sp3 C–H bonds under palla...
Enantioselective Functionalization of Allylic C–H Bonds Following a Strategy of Functionalization and Diversification

We report the enantioselective functionalization of allylic C–H bonds in terminal alkenes by a strategy involving the installation of a temporary functional group at the terminal carbon atom by C–H bond functionalization, followed by the catalytic diversification of this intermediate with a broad scope of reagents. The method consists of a one-pot sequence of palladium-catalyzed allylic C–H bond oxidation under neutral conditions to form linear allyl benzoates, followed by iridium-catalyzed allylic substitution. This overall transformation forms a variety of chiral products containing a new C–N, C–O, C–S, or C–C bond at the allylic position in good yield with a high branched-to-linear selectivity and excellent enantioselectivity (ee ≤97%). The broad scope of the overall process results from separating the oxidation and functionalization steps; by doing so, the scope of nucleophile encompasses those sensitive to direct oxidative functionalization. The high enantioselectivity of the overall process is achie...
Cobalt-Catalyzed C–H Borylation

A family of pincer-ligated cobalt complexes has been synthesized and are active for the catalytic C−H borylation of heterocycles and arenes. The cobalt catalysts operate with high activity and under mild conditions and do not require excess borane reagents. Up to 5000 turnovers for methyl furan-2-carboxylate have been observed at ambient temperature with 0.02 mol % catalyst loadings. A catalytic cycle that relies on a cobalt(I)–(III) redox couple is proposed.
CONSTRAINED LINERS IN REVISION THA: MORE PROBLEMS THAN THEY SOLVE – AFFIRMS

Instability after total hip arthroplasty is the primary cause for revision surgery and is a frequent complication following revision surgery for any reason (Bozic et al, JBJS 2009). Surgical management of the unstable hip has not been uniformly successful with the best results occurring in those hips in which an identifiable cause of instability can be determined (Daly & Morrey, JBJS 1992). It was these sobering findings that lead to the development of and increased use of constrained acetabular components. While the results of revision surgery for instability using constrained components have been encouraging (Shapiro, Padgett, Sculco, J Arthroplasty 2003) with a re-dislocation rate of less than 3%, reoperation for other reasons have noted to increase with time. The commonly used tripolar configuration has been susceptible to bearing damage at both the inner and outer bearing surface by the nature of the constrained mechanism (Shah, Padgett, Wright, J Arthroplasty 2009). In addition, we have noted instances of fixation failure directly related to the constrained acetabular device either from loss of implant fixation to the pelvis with or without cement (Yun, Padgett, Dorr, J Arthroplasty 2005). The observation of these failure modes ranging from either fixation failures to overt biomaterial failure have lead us to be extremely cautious in the “routine” use of constrained liners in revision THR. Implant instability due to poor position should be revised as appropriate to correct alignment. The use of either larger diameter heads or the emerging use of dual mobility articulations seems more appropriate at this time.
Delegating Multiple Decisions

This paper shows how to extend the heuristic of capping an agent against her bias to delegation problems over multiple decisions. Caps may be exactly optimal when the agent has constant biases, in which case a cap corresponds to a ceiling on the weighted average of actions. More generally caps give approximately first-best payoffs when there are many independent decisions. The shape of the cap translates into economic intuition on how to let an agent trade off increases on one action for decreases on other actions. I discuss applications to political delegation, capital investments, monopoly price regulation, and tariff policy.
International Diversification, SFAS 131 and Post‐Earnings‐Announcement Drift

Using 1990 through 2013 data of U.S. firms with foreign operations, we show that (i) the serial correlation of analyst forecast errors increases in the extent of international diversification, (ii) post-earnings-announcement drift (PEAD) based on analyst forecast errors increases in the extent of international diversification, and (iii) the impact of international diversification on the serial correlation of analyst forecast errors and its associated drift is significantly reduced after the implementation of SFAS 131 on segment disclosures. When we replicate our tests using seasonally differenced earnings, we fail to observe similar patterns. Overall, our results suggest that investors’ underreaction to announced earnings is a likely explanation for PEAD. Our findings also indicate that disclosures required under SFAS 131 are useful to analysts in forming efficient earnings expectations, and thereby helping capital market participants in the pricing of internationally diversified firms’ earnings. This article is protected by copyright. All rights reserved.
POLYETHYLENE INSERT EXCHANGE: NOT THE CHIP SHOT IT SEEMS – AFFIRMS

From 1985 through 1997, 56 isolated tibial insert exchange revisions were performed at our institution. Fifty-five patients with wear or instability were included. Those with loosening of any of the components, history of infection, severe knee stiffness or problems with the extensor mechanism were excluded. There were 29 males (1 bilateral) and 26 female patients with a mean age of 66 years (range 35 to 83 years) at the time of revision surgery. Twenty-seven inserts were exchanged based on ligamentous instability, 24 because of insert wear or breakage including two cases of polyethylene dislodgment from the tibial base-plate and 5 for other reasons. Twelve knees had one to three prior revisions. Surveillance from index arthroplasty averaged 8.3 years (range 1.6 to 16.2 years) and since revision 4.6 years (range 2 to 14 years). Knee Society and Function Scores improved from 56 and 50.9 prior to revision to 76 and 59 at final surveillance respectively. Fourteen (25%) of the 56 knees subsequently required re-revision after a mean of only three years (0.5–6.8) from tibial insert exchange. The cumulative survival at 5.5 years was 63.5% (95%CI=+/−14.4, n=19). Of the 27 patients with pre-operative instability, eight were revised and another four were considered as failures due to severe pain. Of the 24 failed inserts, five were re-revised, one was amputated as a result of chronic ankle osteomyelitis concomitant to a chronically painful arthroplasty, and another two inserts failed due to severe pain. Isolated tibial insert exchange led to a surprisingly high early failure rate. Tibial insert exchange should therefore be undertaken with caution as an isolated method of total knee revision surgery even in those circumstances for which the modular insert was designed and felt to be of greatest value.
Multisystem reactions during egg oral food challenges may be associated with less severe reactions on initial presentation

In this study, we assessed whether multisystem reactions to egg and extensively-heated (EH) egg during OFCs were associated with a history of multisystem reactions. Records of children, who underwent OFC to egg or EH egg over a five-year period were reviewed. Of the 120 challenges, 26 (21.67 %) failed, with 38.4 % (10/26) having multisystem reactions. Of the 13 who had multisystem reactions on initial presentation, only two (15.4 %) had a similar OFC outcome. Eighty percent (8/10) of those who had a multisystem OFC reaction had a less severe initial presentation. Initial and OFC multisystem reactions were not associated with each other.
Using Singlet Oxygen to Synthesize Natural Products and Drugs

This Review describes singlet oxygen (1O2) in the organic synthesis of targets on possible 1O2 biosynthetic routes. The visible-light sensitized production of 1O2 is not only useful for synthesis; it is extremely common in nature. This Review is intended to draw a logical link between flow and batch reactions—a combination that leads to the current state of 1O2 in synthesis.
The "Pupil" Factory: Specialization and the Production of Human Capital in Schools

I conducted a randomized field experiment in traditional public elementary schools in Houston, Texas designed to test the potential productivity benefits of teacher specialization. The average impact of encouraging schools to specialize their teachers on student achievement is −0.11 standard deviations per year on a combined index of math and reading test scores. I argue that the results are consistent with a model in which the benefits of specialization driven by sorting teachers into a subset of subjects based on comparative advantage is outweighed by inefficient pedagogy due to having fewer interactions with each student, though other mechanisms are possible.
Structure-based control of complex networks with nonlinear dynamics

What can we learn about controlling a system solely from its underlying network structure? Here we adapt a recently developed framework for control of networks governed by a broad class of nonlinear dynamics that includes the major dynamic models of biological, technological, and social processes. This feedback-based framework provides realizable node overrides that steer a system toward any of its natural long-term dynamic behaviors, regardless of the specific functional forms and system parameters. We use this framework on several real networks, identify the topological characteristics that underlie the predicted node overrides, and compare its predictions to those of structural controllability in control theory. Finally, we demonstrate this framework's applicability in dynamic models of gene regulatory networks and identify nodes whose override is necessary for control in the general case but not in specific model instances.
The Impact of Competing Ads on Click Performance in Sponsored Search

Our research examines the impact of competing ads on click performance of an ad in sponsored search. We use a unique data set of 1,267 advertiser keyword pairs with differing ad quality related to 360 keywords from a search engine to evaluate the click performance. We find that competing high-quality ads, appearing above the focal ad, have a lower negative effect on the click performance as compared to competing low-quality ads. We also find that this effect of competing ads varies with the ad position and the type of keyword. In general, the negative effect of competing high-quality ads decreases at low positions as compared to high positions. Furthermore, this decrease in the negative effect of competing high-quality ads is more substantial for specific keywords. Our results reveal consumer behavior in evaluating different quality ads in sponsored search. More specifically, our results suggest that consumers use the presence of high-quality competing ads as a signal of higher quality of the focal ad. Our findings can help advertisers better evaluate their relative performance for different positions for various types of keywords. This can also help evaluate the efficacy of the auction design mechanism.
shapeDTW: Shape Dynamic Time Warping

Abstract Dynamic Time Warping (DTW) is an algorithm to align temporal sequences with possible local non-linear distortions, and has been widely applied to audio, video and graphics data alignments. DTW is essentially a point-to-point matching method under some boundary and temporal consistency constraints. Although DTW obtains a global optimal solution, it does not necessarily achieve locally sensible matchings. Concretely, two temporal points with entirely dissimilar local structures may be matched by DTW. To address this problem, we propose an improved alignment algorithm, named shape Dynamic Time Warping (shapeDTW), which enhances DTW by taking point-wise local structural information into consideration. shapeDTW is inherently a DTW algorithm, but additionally attempts to pair locally similar structures and to avoid matching points with distinct neighborhood structures. We apply shapeDTW to align audio signal pairs having ground-truth alignments, as well as artificially simulated pairs of aligned sequences, and obtain quantitatively much lower alignment errors than DTW and its two variants. When shapeDTW is used as a distance measure in a nearest neighbor classifier (NN-shapeDTW) to classify time series, it beats DTW on 64 out of 84 UCR time series datasets, with significantly improved classification accuracies. By using a properly designed local structure descriptor, shapeDTW improves accuracies by more than 10% on 18 datasets. To the best of our knowledge, shapeDTW is the first distance measure under the nearest neighbor classifier scheme to significantly outperform DTW, which had been widely recognized as the best distance measure to date. Our code is publicly accessible at: https://github.com/jiapingz/shapeDTW .
Is there a receptor for volatile anesthetics

Because of the presence of inequality of the effect of volatile anesthetics on various neurotransmission systems, a specific receptor is proposed. Nonetheless, the differences are only of the magnitude, and almost all synapses are equally affected. The outstanding features of the action of volatile anesthetics are this wide range of the target, and the steep dose-response curve. The steep dose-response curve indicates that various synapses respond to anesthetics with high cooperativity. When a string of amino acids folds into biologically meaningful structure by enclosing hydrophobic areas inside, some hydrophobic parts are left at the protein-water interface. These hydrophobic patches become the binding site for anesthetics. Because of the wide difference in the structures of anesthetics, it is difficult to assume a specific binding site of lock-and-key type for all anesthetics with all synaptic proteins. Presumably volatile anesthetics bind most hydrophobic patches nonselectively. The affinity to each patch may differ, and the relative specificity to each synapse may ensue. To define these areas as a receptor is a matter of opinion.
Pharmacist-patient communication about medication regimen adjustment during Ramadan.

Objectives During Ramadan, Muslims fast from dawn to sunset while abstaining from food and drink. Although Muslim patients may be aware of their religious exemption from fasting, many patients still choose not to take that exemption and fast. This study examines pharmacists' initiation and timing of communication about medication regimen adjustment (MRA) with patients related to Ramadan. Predictors for initiating this communication with patients were also explored. Methods A probability sample of community pharmacists in Alexandria, Egypt was surveyed. The self-administered instrument covered timing and likelihood of initiating discussion about MRA. Using ordered logistic regression, a model was estimated to predict pharmacists' initiation of the conversation on MRA during Ramadan. Results Ninety-three percent of the 298 approached pharmacists completed surveys. Only 16% of the pharmacists reported that they themselves usually initiated the conversation on MRA. Pharmacists' initiation of these conversations was associated with pharmacists' perceived importance of MRA on pharmacy revenue odds ratio ((OR) = 1.24, CI = 1.03–1.48). Eighty percent of the responding pharmacists reported the MRA conversation for chronic conditions started either 1–3 days before, or during the first week of Ramadan. Conclusion These results suggest considerable pharmacist patient communication gaps regarding medication use during Ramadan. It is especially important for pharmacists and other health professionals to initiate communication with Muslim patients early enough to identify how best to help patients transition safely into and out of Ramadan as they fast.
Patellar revision: bringing back the bone.

Severe patellar loss, which precludes adequate fixation of another patellar implant, may be treated by patellectomy, retention of the remaining patellar bony shell (resection arthroplasty), gull wing osteotomy, or patellar bone grafting. In contrast to other treatment alternatives, patellar bone grafting uniquely imparts the potential for restoration of patellar bone. Technique: It is helpful to retain the pseudomeniscus of scar tissue and most of the peripatellar fibrosis tissue to facilitate suture fixation of the tissue flap to the patellar rim. The patellar shell is prepared by removing all fibrous membrane in the crevices of the remaining patellar bone. The tissue flap is created from one of several sources including large flaps of peripatellar fibrotic tissue or a free tissue flap obtained from either the suprapatellar pouch or the fascia lata obtained in the lateral gutter of the knee joint. The tissue flap is sewn to the peripheral patellar rim and peripatellar fibrosis tissue with multiple, nonabsorbable size zero sutures to provide a watertight closure. A small purse string opening is left in one portion of the tissue flap repair to facilitate delivery of bone graft into the patellar defect. Cancellous autograft is harvested from the metaphyseal portion of the central femur during preparation of the femur for the revision implant. In the absence of locally available cancellous autograft, cancellous allograft bone can be used. The bone graft is prepared by morsellising the bone into small fragments of approximately 5 to 8 mm in height and width to facilitate tight impaction of the bone graft into the patellar shell-tissue flap construct. The bone graft is tightly impacted through the opening of the fascial flap into the patellar bone defect with enough volume so that the height of the final patellar construct has a final height measuring more than 20 mm. The tissue flap is then completely closed to contain the bone graft within the patellar shell. The peripatellar arthrotomy is provisionally repaired with several sutures or towel clips to mould the patellar construct in the femoral trochlea as the knee is placed through the full range of motion. Postoperative rehabilitation is not altered from the usual revision knee arthroplasty protocol. In contrast with the treatment alternatives of patellectomy or retention of the bony shell, this new surgical procedure uniquely imparts the potential for restoration of patellar bone stock and may improve the functional outcome in these patients by facilitating patellar tracking and improving quadriceps leverage. The procedure is simple to perform and does not require sophisticated instrumentation or a long learning curve. Based on the current satisfactory short-term to mid-term clinical results, this surgical procedure provides an important addition to the armamentarium of the revision knee arthroplasty surgeon.
Regiocontrolled Oxidative C–C Coupling of Dienol Ethers and 1,3-Dicarbonyl Compounds

A strategy for synthesis of γ-alkylated enones through oxidative coupling of siloxydienes and 1,3-dicarbonyl compounds is reported. This method is an interrupted form of our formal [3 + 2] cycloaddition method reported previously. The present work excels in generating all-carbon quaternary centers via C–C bond formation at the remote γ-site which is traditionally challenging to functionalize. Stereoselectivity and functional group tolerance are examined in complex systems. Double alkylation reactions are also described.
Scalable C–H Oxidation with Copper: Synthesis of Polyoxypregnanes

Steroids bearing C12 oxidations are widespread in nature, yet only one preparative chemical method addresses this challenge in a low-yielding and not fully understood fashion: Schonecker’s Cu-mediated oxidation. This work shines new light onto this powerful C–H oxidation method through mechanistic investigation, optimization, and wider application. Culminating in a scalable, rapid, high-yielding, and operationally simple protocol, this procedure is applied to the first synthesis of several parent polyoxypregnane natural products, representing a gateway to over 100 family members.
Appeal for cultural equity

Man has a more indirect relation to nature than most other animals because his environmental tie is normally mediated by a cultural system. Since human adaptation has been largely cultural rather than biological, human sub-species are rather the product of shifts in learned culture patterns than in genetically inherited traits. It is the flexibility of these culture patterns — composed of technique, social organization, and communication — that has enabled the human species to flourish in every zone of the planet.
Light quark Yukawa couplings from Higgs kinematics

We show that the normalized Higgs production p T and y h distributions are sensitive probes of Higgs couplings to light quarks. For up and/or down quark Yukawa couplings comparable to the SM b quark Yukawa the ūu or $$ \overline{d}d $$ fusion production of the Higgs could lead to appreciable softer p T distribution than in the SM. The rapidity distribution, on the other hand, becomes more forward. We find that, owing partially to a downward fluctuation, one can derive competitive bounds on the two couplings using ATLAS measurements of normalized p T distribution at 8 TeV. With 300 fb−1 at 13 TeV LHC one could establish flavor non-universality of the Yukawa couplings in the down sector.
Performance analysis of multiple priorities on token ring LANs to support multimedia

Transporting multimedia traffic is becoming an essential requirement for communications networks. Unlike data traffic, multimedia traffic has strict demands on latency, throughput, filter, and bandwidth. This paper demonstrates the capabilities of the currently available 16-Mbps token ring to simultaneously carry data and multimedia traffic. Experimental data and simulation results that show the effects of data on multimedia traffic and vice versa are presented. The use of the token ring priority mechanism for traffic regulation is demonstrated. The use of multiple levels of priorities for multimedia traffic is shown to be needed to meet the performance requirements of various types of multimedia traffic. Furthermore, the results show that these requirements can be met in the presence of bursty data traffic.
If politics is the problem, how can external actors be part of the solution ?

Despite a large body of evidence on the policies and institutions needed to generate growth and reduce poverty, many governments fail to adopt these policies or establish the institutions. Research advances since the 1990s have explained this syndrome, which this paper generically calls “government failure”, in terms of the incentives facing politicians, and the underlying political institutions that lead to those incentives. Meanwhile, development assistance, which is intended to generate growth and reduce poverty, has hardly changed since the 1950s, when it was thought that the problem was one of market failure. Most assistance is still delivered to governments, in the form of finance and knowledge that are bundled together as a “project”. Drawing on recent research on the politics of government failure, the paper shows how traditional development assistance can contribute to the persistence of government failures. It proposes a new model of development assistance that can help societies transition to better institutions. Specifically, the paper suggests that knowledge be provided to citizens to build their capacity to select and sanction leaders who have the political will and legitimacy to deliver the public goods needed for development. As for the financial transfer, which for various reasons has to be delivered to governments, the paper proposes that this be provided in a lump-sum manner (that is, not linked to individual projects), conditional on the governments following broadly favorable policies and making information available to citizens.