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How well can social scientists predict societal change, and what processes underlie their predictions? To answer these questions, we ran two forecasting tournaments testing accuracy of predictions of societal change in domains commonly studied in the social sciences: ideological preferences, political polarization, life satisfaction, sentiment on social media, and gender-career and racial bias. Following provision of historical trend data on the domain, social scientists submitted pre-registered monthly forecasts for a year (Tournament 1; N=86 teams/359 forecasts), with an opportunity to update forecasts based on new data six months later (Tournament 2; N=120 teams/546 forecasts). Benchmarking forecasting accuracy revealed that social scientists’ forecasts were on average no more accurate than simple statistical models (historical means, random walk, or linear regressions) or the aggregate forecasts of a sample from the general public (N=802). However, scientists were more accurate if they had scientific expertise in a prediction domain, were interdisciplinary, used simpler models, and based predictions on prior data.

© 2019 American Speech-Language-Hearing Association. Purpose: The purpose of this letter is to respond to Marcotte’s (2019) letter to the editor, “The Influence of Treatment on Children’s Recovery from Stuttering: Comments on Kefalianos et al. (2017) and Leech et al. (2017),” published by the Journal of Speech, Language, and Hearing Research.

One of the greatest impediments to vesicular-arbuscular mycorrhizal (VAM) fungi inoculation of field crops is the bulk and weight of inoculum required. The Glomus spp. inoculum was then shown to be the best inoculant with pukekohe long keeper onions in a field trial on the Patumahoe soil, amply vindicating the effort of prior fungal selection. Pure cultured inoculum of VAM fungi is not yet available, thus, in many field trials, plants have been inoculated by placing pads of mycorrhiza-infested soil below each seed. Pelleting is a successful inoculum formulation when the seedling radicle passing down through the inoculum becomes primarily infected with the fungi in the pellet before it comes into contact with the indigenous mycorrhizal fungi in the field soil. Inoculum placement is not crucial, as the nursery potting mix can be thoroughly infested with VAM inoculum, and there are no indigenous mycorrhizal fungi to compete with the inoculant fungi for root space.

Purpose: For a community cohort of children confirmed to have stuttered by the age of 4 years, we report (a) the recovery rate from stuttering, (b) predictors of recovery, and (c) comorbidities at the age of 7 years. Method: This study was nested in the Early Language in Victoria Study. Predictors of stuttering recovery included child, family, and environmental measures and first-degree relative history of stuttering. Comorbidities examined at 7 years included temperament, language, nonverbal cognition, and health-related quality of life. Results: The recovery rate by the age of 7 years was 65%. Girls with stronger communication skills at the age of 2 years had higher odds of recovery (adjusted OR = 7.1, 95% CI [1.3, 37.9], p =.02), but similar effects were not evident for boys (adjusted OR = 0.5, 95% CI [0.3, 1.1], p =.10). At the age of 7 years, children who had recovered from stuttering were more likely to have stronger language skills than children whose stuttering persisted (p =.05). No evident differences were identified on other outcomes including nonverbal cognition, temperament, and parent-reported quality of life. Conclusion: Overall, findings suggested that there may be associations between language ability and recovery from stuttering. Subsequent research is needed to explore the directionality of this relationship.

A 3'-N,5'-S-bridging thiophosphoramidate analogue of thymidylyl-3ʹ,5ʹ-thymidine was synthesised under aqueous conditions. 1H NMR conformational measurements show that the 3'-N-substituted deoxyribose ring is biased towards the 'north', RNA-like conformation. Rate constants for hydrolysis of the analogue were measured at 90 °C in the pH range 1.3-10.9. The pH-log kobs profile displays a pH-independent region between approximately pH 7 and 10 (t½ ~13 days). Under acidic conditions, kobs displays a first order dependence on [H3O+].

We demonstrate N-phosphorylation and N-thiophosphorylation of unprotected aminonucleosides in aqueous media. N-Phosphorylations using phosphoric chloride and N-thiophosphorylations using thiophosphoryl chloride were explored as functions of pH using 5′-amino-5′-deoxyguanosine as substrate. These reagents were compared to phosphodichloridate and thiophosphodichloridate ions, and the methodology was applied to other aminonucleosides. S-Alkylations of the nucleoside N-thiophosphoramidates were investigated as functions of pH and alkylating agent.

The International Reactor Innovative and Secure (IRIS) is modular, economic, medium size (1000 MWth), grid appropriate and based on the safety-by-designTM philosophy. The integral configuration of the primary system, the strong coupling of reactor vessel and containment, during accident conditions, and the passive safety systems guarantee a very high degree of inherent safety. The IRIS International Consortium, that led by Westinghouse has developed the plant design, is strongly pursuing the objective to obtain the Final Design Approval (FDA) by the U.S. Nuclear Regulatory Commission (NRC), by 2013.The relative licensing process requires the execution of integral and separate effect tests on a properly scaled reactor simulator. Within the framework of an Italian R&D program on Nuclear Fission, managed by ENEA and supported by the Ministry of Economic Development, the SPES3 facility is being designed and will be built at SIET laboratories. In the early 90s, the SIET company upgraded the SPES facility (simulating a three loop PWR for the italian PUN - Progetto Unificato Nazionale) in SPES2, providing the experimental data that allowed the licensing of the Westinghouse AP-600 reactor. On the basis of the lessons learned and relying on existing auxiliary systems, the simulation of an accidental sequences matrix on the SPES3 facility will provide the needed experimental results to verify the general behaviour of the system and allow a code assessment process suitable to produce a reliable tool for the IRIS plant analyses.The main scaling parameters for the facility design have been determined through a Phenomena Identification and Ranking Table (PIRT) and a Hierarchical Two-Tired Scaling Analysis (H2TS) process resulting in 1:100 volume and power scale, 1:1 elevation scale, prototypical fluid at plant pressure and temperature nominal conditions. The detailed scaling of all plant components is the result of an iterative process between a Top-Down system scaling and Bottom-Up process scaling, i.e. a continuous verification of the experimental facility component design adequacy to appropriately represent what expected in the plant.The SPES3 facility simulates the primary, secondary and containment systems of the IRIS reactor. The Reactor Vessel (RV) includes the fuel bundle with electrically heated rods, the inverted hat pressurizer (PRZ) and three helical coil steam generators (SG) simulating the eight IRIS SGs. A single outer pump simulates the eight IRIS primary internal circulation pumps. Two Emergency Boration Tanks (EBT), the two Direct Vessel Injection (DVI) lines and the Automatic Depressurization System (ADS) are also simulated.The secondary side feed lines and steam lines are simulated up to the main isolation valves and the three Emergency Heat Removal Systems (EHRS) represent the four trains of the IRIS primary safety system. The facility configuration is suitable to investigate the natural circulation loops that allow removing the decay heat during the long term accidental transients. The IRIS containment compartments are simulated in SPES3 by appropriately connected separated tanks, representing the Dry-Well (DW), two Pressure Suppression Systems (PSS), two Long Term Gravity Make-up Systems (LGMS), the Reactor Cavity (RC) and the ADS Quench Tank (QT). Shape and dimensions are fixed in order to reproduce the trend of IRIS compartment volumes versus height. Both the primary and secondary loops are designed for 17.25 MPa pressure and the corresponding saturation temperature. The containment tanks are designed for 2 MPa pressure and the corresponding saturation temperature.In order to fit the new facility components and pipes on the existing steel structure of SPES2, an appropriate design of piping layout has been defined.A large set of instruments (about 600) will be installed on SPES3 to provide data both for the test run and analysis. It will consist of conventional (relative and absolute pressure transmitters and temperature sensors) and special (for two-phase flow measurement) instrumentation.The planned test matrix consists of 13 integral tests and 2 separate effect tests. The integral tests, which will simulate Design Basis Accidents (DBA) and Beyond Design Basis Accidents (BDBA) scenarios, are aimed at assessing the plant response and verifying the safety system effectiveness. The considered accidental events consist of a series of split and Double Ended Guillotine (DEG) breaks, ranging from 2 to 6 inch equivalent, on the main piping of the primary and secondary sides (DVI, EBT balance line and ADS, Feed Line and Steam line). The separate effect tests are devoted to investigate the interaction and characterize the heat transfer of innovative design components like the helical coil steam generators and the EHRS for the long term removal of the decay heat.The Relap5 code is used for the complete simulation of the facility through the three steps planned to achieve the foreseen objectives: a) Supporting design analyses aimed at obtaining feedback information on the facility design (in particular the comparison between the SPES3 facility and the IRIS reactor simulations through the Relap5+Gothic codes will provide information on the appropriateness of the performed scaling choices); b) Pre-test analyses aimed at the test design and test procedure set-up; c) Post-test analyses and code assessment on a set of qualified data to be used to tune the IRIS-specific analyses.Thanks to the iteration between facility design and analysis, the SPES3 facility will provide suitable experimental data of the main tests required by the NRC. The code assessment on such data will guarantee a reliable tool to perform the IRIS reactor safety analyses necessary for the Final Design Approval.

The International Reactor Innovative and Secure (IRIS) is a modular, economic, medium size (1000 MWth), grid appropriate reactor belonging to the Innovative Nuclear Power Plants (NPP), in which a new plant configuration is obtained through the evolution of the mature PWR technology with a safety-by-designTM approach. The IRIS International Consortium, led by Westinghouse, is finalizing the design with the objective of obtaining the Final Design Approval (FDA) by the U.S. Nuclear Regulatory Commission (NRC), by 2013. The main feature of the IRIS is an integral primary system configuration with all main components contained in the Reactor Vessel (RV): pressurizer, primary circulation pumps and once-through helical coil steam generators. A compact spherical steel containment is part of the IRIS safety systems and is involved in a coupled dynamic behaviour in the passive mitigation strategy which enhances the safety and reliability of the IRIS.One of the steps required by the licensing process is the execution of integral and separate effect tests on a properly scaled reactor simulator of the IRIS reactor. The SPES3 facility is being designed and will be built at SIET laboratories in the framework of an Italian R&D program on Nuclear Fission, managed by ENEA and supported by the Ministry of Economic Development. The simulation of a series of accidental sequences will provide data to verify the general behaviour of the system and allow a wide code assessment guaranteeing a reliable tool for the IRIS plant analyses.In the early 90s, the SIET company upgraded the SPES facility (simulating a three loop PWR for the italian PUN - Progetto Unificato Nazionale) in SPES2, providing the experimental data that allowed the licensing of the W AP-600 reactor. On the basis of the gained experience and relying on the same auxiliary systems as SPES2, the SPES3 will provide the experimental results in sight of the IRIS Final Design Approval (FDA) by 2013. The main scaling parameters were defined on the basis of a Phenomena Identification and Ranking Table (PIRT) and of a Hierarchical Two-Tired Scaling Analysis (H2TS) methodology. The IRIS System Decomposition and the Scale Identification (first two steps of H2TS) led to choose 1:100 volume and power scale, 1:1 elevation scale, prototypical fluid at plant pressure and temperature nominal conditions. The detailed scaling of all components of the plant is the result of an iterative process between a Top-Down system scaling and Bottom-Up process scaling, i.e. a continuous verification if the experimental facility component design choices are suitable to represent what expected in the plant. The SPES3 facility simulates the primary, secondary and containment systems of the IRIS reactor. The Reactor Vessel (RV) includes the fuel bundle with electrically heated rods, the inverted hat pressurizer (PRZ) and three helical coil steam generators (SG) simulating the eight IRIS SG modules. A single outer pump simulates the eight IRIS internal primary circulation pumps. Two Emergency Boration Tanks (EBT), the Direct Vessel Injection (DVI) lines and the Automatic Depressurization System (ADS) are also simulated.The secondary side feed lines and steam lines are simulated up to the main isolation valves and the three Emergency Heat Removal Systems (EHRS), represent the four trains of the IRIS primary safety system. The facility configuration is suitable to investigate the natural circulation loops that allow the decay heat removal during the long term accidental transients. Both primary and secondary side are designed for 17.25 MPa pressure and the corresponding saturation temperature.The IRIS containment compartments are simulated in SPES3 by separate tanks, connected by pipes. The tanks, in particular, represent the Dry-Well (DW), two Pressure Suppression Systems (PSS), two Long Term Gravity Make-up Systems (LGMS), the Reactor Cavity (RC) and the ADS Quench Tank (QT). In some cases, the shape of the tanks differs from cylindrical in order to reproduce the trend of IRIS plena volumes versus height. The containment tanks are designed for 2 MPa pressure and the corresponding saturation temperature.A complex design of piping layout allows to fit the new facility components and pipes on the existing steel structure that housed the SPES2. The SPES3 facility will be equipped with about 600 instruments, mainly of conventional type, like relative and absolute pressure transmitters and temperature sensors. Special instrumentation for two-phase flow measurement will be installed too. A matrix, including 15 tests: 13 for integral effects and 2 for separate effects, is foreseen on SPES3. The integral tests are devoted to verify the facility response and safety system effectiveness to take the plant in safe conditions after Design Basis Accidents (DBA) and Beyond Design Basis Accidents (BDBA). Split and Double Ended Guillotine (DEG) Small Break Loca Accidents (LOCA) are foreseen both on the primary side (DVI, EBT balance line and ADS) and the secondary side (Feed Line and Steam line) ranging from 2 to 6 inch equivalent.The separate effect tests are devoted to investigate and characterize the behaviour of innovative design components like the helical coil steam generators and their interaction/heat transfer capabilities with the EHRS.The Relap5 code is used to simulate the SPES3 facility in all its parts. Three steps are foreseen: a) Supporting design analyses aimed at obtaining feedback information on the facility design. In particular the comparison between the SPES3 facility and the IRIS reactor simulations (Relap5+Gothic codes) will provide information on the correctness of the performed choices; b) Pre-test analyses aimed at the test design and test procedure set-up; c) Post-test analyses and code assessment on a set of qualified data.The SPES3 facility will provide experimental data of the main tests required by the NRC. The code assessment on such data will guarantee a reliable tool to perform the IRIS reactor safety analyses in sight of the Final Design Approval.

The IRIS integral reactor is on the path towards licensing. The paper deals with the study, design and set up of the experimental facility for the performance of the Integral Effect Tests (IET). IRIS owns specific layout, i.e. the integral configuration, and enhanced safety features, obtained also by exploiting a coupled dynamic behaviour during the accident sequences among the primary vessel and its components, the steel spherical containment and the passive safety systems. These design choices, very positive for the safety point of view, however require that the scaled simulator of the reactor must be able to simulate the dynamic behaviour of all the systems, containment included. The PIRT (Phenomena Identification and Ranking Table) analysis and the H2TS (Hierarchical, Two-Tired Scaling Analysis) process were adopted, leading to a 1:1 scaling in height, 1:100 in volume and power and with the fluid in prototypical conditions. A brief description of the facility is reported and a preliminary Text Matrix is presented as well.