Subsequent Flash Research Articles

Enhancing strength-ductility synergy in low-Mn lightweight steel by large-deformed warm rolling and flash annealing

The presence of δ-ferrite makes it challenging to achieve higher strength-ductility in low-Mn lightweight steels. In this study, a large deformation warm rolling process was used to construct a precursor enriched with Mn, nano-precipitations, ultra-fine grains, and high-density dislocations. The subsequent flash annealing process not only promotes the formation of multi-heterogeneous structures but also refines and reduces δ-ferrite while increasing the ultrafine-grained hard phase martensite. Additionally, this process enhances the retention of retained austenite, whose ultrafine grains contribute to improved mechanical stability. The synergistic effect of multiple strengthening mechanisms enables low-Mn lightweight steel to achieve outstanding comprehensive mechanical properties, with a tensile strength of 1423 MPa and a total elongation of 23.0 %.

Dual nanoprecipitation and nanoscale chemical heterogeneity in a secondary hardening steel for ultrahigh strength and large uniform elongation

Nanoprecipitates and nanoscale retained austenite (RA) with suitable stability play crucial roles in determining the yield strength (YS) and ductility of ultrahigh strength steels (UHSSs). However, owing to the kinetics incompatibility between nanoprecipitation and austenite reversion, it is highly challenging to simultaneously introduce high-density nanoprecipitates and optimized RA in UHSSs. In this work, through the combination of austenite reversion treatment (ART) and subsequent flash austenitizing (FA), nanoscale chemical heterogeneity was successfully introduced into a low-cost UHSS prior to the aging process. This chemical heterogeneity involved the enrichment of Mn and Ni in the austenite phase. The resulting UHSS exhibited dual-nanoprecipitation of Ni(Al,Mn) and (Mo,Cr)2C and nanoscale austenite stabilized via Mn and Ni enrichment. The hard martensitic matrix strengthened by high-density dual-nanoprecipitates constrains the plastic deformation of soft RA with a relatively low fraction of ∼15 %, and the presence of relatively stable nanoscale RA with adequate Mn and Ni enrichment leads to a marginal loss in YS but keeps a persistent transformation-induced plasticity (TRIP) effect. As a result, the newly-developed UHSS exhibits an ultrahigh YS of ∼ 1.7 GPa, an ultimate tensile strength (UTS) of ∼1.8 GPa, a large uniform elongation (UE) of ∼8.5 %, and a total elongation (TE) of ∼13 %. The strategy of presetting chemical heterogeneity to introduce proper metastable phases before aging can be extended to other UHSSs and precipitation-hardened alloys.

New insights on clinical perspectives of FLASH radiotherapy: from low- to very high electron energy.

Radiotherapy (RT) is performed in approximately 75% of patients with cancer, and its efficacy is often hampered by the low tolerance of the surrounding normal tissues. Recent advancements have demonstrated the potential to widen the therapeutic window using "very short" radiation treatment delivery (from a conventional dose rate between 0.5 Gy/min and 2 Gy/min to more than 40 Gy/s) causing a significant increase of normal tissue tolerance without varying the tumor effect. This phenomenon is called "FLASH Effect (FE)" and has been discovered by using electrons. Although several physical, dosimetric, and radiobiological aspects need to be clarified, current preclinical "in vivo" studies have reported a significant protective effect of FLASH RT on neurocognitive function, skin toxicity, lung fibrosis, and bowel injury. Therefore, the current radiobiological premises lay the foundation for groundbreaking potentials in clinical translation, which could be addressed to an initial application of Low Energy Electron FLASH (LEE) for the treatment of superficial tumors to a subsequent Very High Energy Electron FLASH (VHEE) for the treatment of deep tumors. Herein, we report a clinical investigational scenario that, if supported by preclinical studies, could be drawn in the near future.

On the flash sintering behavior of Li:ZnO—Evidence of electrode asymmetry driven by electrochemical reactions

AbstractThe synthesis, subsequent flash sintering (FS) characteristics and microstructures of pure and Li‐incorporated ZnO powders are reported. At low concentrations, Li is a substitutional occupant in ZnO but becomes an amphoteric dopant (substitutional and interstitial occupant) at higher concentrations inferred from a contraction reversal of the unit cell volume. Increasing Li reduces the average flash temperature of ZnO modestly by 15°C, and a doubling of the linear shrinkage. A discernible color smear (yellow–white–dark) stretching from the anode to cathode imputable to strong electromigration is also observed. Microanalyses of the electrode regions establish clear evidence of electrochemical (EC) lithiation into ZnO and the formation of Li–Zn compounds not observed in conventional sintering (CS). Interestingly, in contrast to CS, the addition of Li enhances coarsening during FS, suggestive of a dissolution–reprecipitation process concurrent with the EC lithiation process. Evidence for considerable (local) yet tangible temperature, chemical and microstructural asymmetry among electrodes driven by EC reactions is presented. Probable mechanisms, leading to these observations, are discussed.

NMR-based Phytochemical Profiling of Palmyra Palm Syrup Infused with Dry Ginger, Black Pepper, and Long Pepper

Background: Trikatu, a vital ingredient in many Indian Ayurvedic drugs, is a consortium of three spices, viz. dry ginger, black pepper, and long pepper, known for its peculiar pungency. To convert Trikatu into a widely acceptable palatable form, we blended these three spices in a decoction form and added them to syrup prepared from palmyra palm neera, which resulted in ‘Trikatu Syrup’ (TS). Recently, we reported in vivo immunomodulatory properties of TS. Introduction: The immunomodulatory effects of spices are attributed largely to the presence of certain phytochemicals. The importance of phytochemicals in spices as immunomodulatory agents necessitate a thorough investigation of these bioactives in formulations comprising spices. In the present study, we have focused on understanding the retention of spice and syrup-based phytochemicals in the formulated product that assists in product standardization of TS. Methods: NMR serves as a highly reliable tool for explicit structural confirmation of phytochemicals when compared to HPLC or mass spectrometry tools. NMR spectra of a phytochemical, whether in pure form or when the phytochemical is a part of the mixture, enable qualitative and quantitative studies with a mixture of phytochemicals in organic extracts of food matrices. Hence, the NMR spectral comparison of compounds isolated from the organic extracts of TS is described here. Results: Fractionation of TS using Diaion® HP-20 resulted in the partitioning of compounds based on their polarity. Purification of the acetone fraction by column chromatography aided in the efficient isolation of compound 1 (pellitorine), compound 2 (piperine), compounds 3-5 (trienamides), and compound 6 (pipataline). Acetonitrile fraction yielded compound 7 (uridine) and compound 8 (3-O-methylmyo- inositol), which were neither reported in the three spices nor palmyra palm. A qualitative display of the acetone fraction of TS with its phytochemicals 1-6 served as a fingerprint of TS. Conclusion: In summary, TS, a palatable spice-based nutraceutical in palmyra palm syrup with immunomodulatory potential, was thoroughly investigated for the phytochemical composition of its organic fractions. The process of fractionating TS using Diaion® HP-20, subsequent flash purification, and column chromatography facilitated the isolation of prominent phytochemicals. We report the utility of NMR as a reliable and efficient tool for fingerprinting phytochemicals in formulations, nutraceuticals, etc., which assists in ascertaining their authenticity.

Atmospheric flash annealing of low-dimensional vanadium nanolayers sputtered on glass substrates

A simple approach to attain low-dimensional, highly transparent VO2-based thermochromic coatings on glass substrates is reported. This two-step procedure comprises the initial deposition of DC magnetron-sputtered vanadium films and the subsequent flash annealing of such layers in air atmosphere. The careful control of the thermal treatment parameters and characterizations carried out by scanning electron microscopy and variable temperature Vis-NIR spectrophotometry allowed the optimization of VO2 yields for 12.5 nm and 25 nm thick layers. The impact of layer thickness and the nature of the thermal treatment itself on the thermochromic features of such systems were also evaluated. In this sense, the resulting systems developed asymmetric transmittance vs. temperature hysteresis loops as well as a surprisingly advantageous lowering of the phase transition temperature, which is achieved without the incorporation of dopants. The most promising results were obtained for a 12.5 nm thick layer flash annealed at 475 °C, which, despite having a moderate solar modulation ability (∼2%), could be a potential candidate for smart windows applications given its high Vis-NIR transparency (> 60%) coupled with its low transition temperature of 16 °C below the standard value for pure VO2.

Conductive Inks Based on Melamine Intercalated Graphene Nanosheets for Inkjet Printed Flexible Electronics.

With the growing number of flexible electronics applications, environmentally benign ways of mass-producing graphene electronics are sought. In this study, we present a scalable mechanochemical route for the exfoliation of graphite in a planetary ball mill with melamine to form melamine-intercalated graphene nanosheets (M-GNS). M-GNS morphology was evaluated, revealing small particles, down to 14 nm in diameter and 0.4 nm thick. The M-GNS were used as a functional material in the formulation of an inkjet-printable conductive ink, based on green solvents: water, ethanol, and ethylene glycol. The ink satisfied restrictions regarding stability and nanoparticle size; in addition, it was successfully inkjet printed on plastic sheets. Thermal and photonic post-print processing were evaluated as a means of reducing the electrical resistance of the printed features. Minimal sheet resistance values (5 kΩ/sq for 10 printed layers and 626 Ω/sq for 20 printed layers) were obtained on polyimide sheets, after thermal annealing for 1 h at 400 °C and a subsequent single intense pulsed light flash. Lastly, a proof-of-concept simple flexible printed circuit consisting of a battery-powered LED was realized. The demonstrated approach presents an environmentally friendly alternative to mass-producing graphene-based printed flexible electronics.

Hydrometeorological evaluation of two nowcasting systems for Mediterranean heavy precipitation events with operational considerations

Abstract. Heavy precipitation events and subsequent flash floods regularly affect the Mediterranean coastal regions. In these situations, forecasting rainfall and river discharges is crucial especially up to 6 h, which is a relevant lead time for emergency services in times of crisis. The present study investigates the hydrometeorological skills of two new nowcasting systems: a numerical weather model AROME-NWC and a nowcasting system blending numerical weather prediction and extrapolation of radar estimation called PIAF. Their performance is assessed for 10 past heavy precipitation events that occurred in southeastern France. Precipitation forecasts are evaluated at a 15- min time resolution and the availability times of forecasts, based on the operational Météo-France suites, are taken into account when performing the evaluation. Rainfall observations and forecasts were first compared using a point-to-point approach. Then the evaluation was conducted from an hydrological point of view, by comparing observed and forecast precipitation over watersheds affected by floods. In general, the results led to the same conclusions for both evaluations. On the very first lead times, up to 1 h 15 min and 1 h 30 min of forecast, the performance of PIAF was higher than AROME-NWC. For longer lead times (up to 3 h) their performances were generally equivalent. An assessment of river discharges simulated with the ISBA-TOP coupled system, which is dedicated to Mediterranean flash flood simulations and driven by AROME-NWC and PIAF rainfall forecasts, was also performed on two exceptional past flash flood events. The results obtained for these two events show that using AROME-NWC or PIAF rainfall forecasts is promising for flash flood forecasting in terms of peak intensity, timing, and first wave of discharge, with an anticipation of these phenomena that can reach several hours.

Hydrometeorological analysis of the 12 and 13 September 2019 widespread flash flooding in eastern Spain

Abstract. On 12 and 13 September 2019, a long-lasting heavy precipitation episode (HPE) affected the València, Murcia and Almería regions in eastern Spain. Observed rainfall amounts were close to 500 mm in 48 h, being the highest cumulative precipitation registered in some rain gauges for the last century. Subsequent widespread flash flooding caused seven fatalities and estimated economical losses above EUR 425 million. High-resolution precipitation estimates from weather radar observations and flood response from stream gauges are used in combination with a fully distributed hydrological model to examine the main hydrometeorological processes within the HyMeX programme. This HPE was characterized by successive, well-organized convective structures that impacted a spatial extent of 7500 km2, with rainfall amounts equal to or larger than 200 mm. The main factors driving the flood response were quasi-stationarity of heavy precipitation, very dry initial soil moisture conditions and large storage capacities. Most of the examined catchments exhibited a dampened and delayed hydrological response to cumulative precipitation: until runoff thresholds were exceeded, infiltration-excess runoff generation did not start. This threshold-based hydrological behaviour may impact the shape of flood peak distributions, hindering strict flood frequency statistical analysis due to the generally limited lengths of data records in arid and semi-arid catchments. As an alternative, a power-law relationship is analytically derived to specifically link flood magnitude to rainfall amount, with the parameters depending on basin and precipitation features. This power law could aid in developing empirical envelope curves so as to assess hydrologic risk in arid and semi-arid catchments with a threshold-based hydrological behaviour.

Reconstruction of active surface deformation in the Rishi Ganga basin, Central Himalaya using PSInSAR: A feedback towards understanding the 7th February 2021 Flash Flood

Active surface deformation, displacement pattern, and erosional variability is estimated using the geomorphologically sensitive morphometry along with the Persistent Scatterer Interferometric Synthetic Aperture Radar (PSInSAR) technique using the Sentinel-1Adata (119 images) acquired between 07- 02-2017 and 10-02-2021. The average velocities for this dataset are estimated to be between ±11 mm/y. The Raunthi River catchment from where the flood was triggered is undergoing ~8 mm/y subsidence and ~10 mm/y uplift. Compared to this the basin wide deformation (Rishi Ganga basin) is estimated to be around ±10 mm/y with commulative ground displacement of around ±45 mm. The times series analysis suggests an increase in the ground displacement by around 5 mm/y and seems to be responsible for the expansion of pre-existing cracks in the vicinity of the Vaikrita Thrust (VT) and subsequent failure of the northern face of Nandi Peak on 7th February 2021. The Global Positioning System (GPS) derived strain distribution pattern indicate a relatively higher accumulation of strain (>0.35µ strain/y). The normalized steepness index (ksn) variation along the longitudinal section of Rishi Ganga and Raunthi River sub-basin in Central Himalayan region shows anomalous increase at the glacio-fluvial transitional processes. Moreover, the χ profiles as well as planform plots shows anomalously lower values within the Raunthi River sub-basin when compared with the Rishi Ganga basin. Based on the lower values of χ it is observed that Raunthi River sub-basin is undergoing high erosion which can be caused by the presence of sheared lithology and incision of the relict glacial and paraglacial sediments. We negate the suggestion that abrupt rise in the temperature was the major triggering mechanism for the recent disaster, instead it is the sheared lithology and pre-existing fissure developed because of differential uplift and subsidence in Raunthi River that led to the wedge failure and subsequent flash flood. Had the climate was the major driver of the recent tragedy ?, it should have impacted multiple hanging glaciers in the Rishi Ganga valley. Therefore, the study calls for detailed geomorphological, structural and glaciological investigation in regions dominated by glacial and paraglacial processes in the strategic regions of the Himalaya. Towards this, the state of art PSInSAR technique seems to provide fast and reliable detection of terrain instability/stability along with identification of potential areas of slope failures in near future in the glacial and preglacial zones.

Isolation and quantification of diarylheptanoids from European hornbeam (Carpinus betulus L.) and HPLC-ESI-MS/MS characterization of its antioxidative phenolics

Detailed polyphenol profiling of European hornbeam (Carpinus betulus L.) bark, leaf, male and female catkin extracts was performed by high-performance liquid chromatography–diode array detection coupled to tandem mass spectrometry (HPLC-DAD-MS/MS). A total of 194 compounds were characterized and tentatively identified. Gallo- and ellagitannins dominated in the methanol extracts, while flavonol glycosides and methoxylated flavones prevailed in the ethyl acetate samples. In the quest for diarylheptanoids, twelve compounds were isolated by the combination of subsequent reversed-phase flash chromatographic and high-performance liquid chromatographic methods. The structural elucidation of the isolated components was performed by ultrahigh-performance liquid chromatography-Orbitrap mass spectrometry (UHPLC‐Orbitrap‐MS) as well as 1D and 2D nuclear magnetic resonance (NMR) spectroscopy. Six known cyclic diarylheptanoids, together with a new compound were described in Carpinus betulus for the first time. The occurrence of a linear diarylheptanoid and a lignan has also been unprecedented in the genus Carpinus. Moreover, three known flavonol glycosides were isolated. Based on the identification of characteristic fragment ions, a new mass spectrometric fragmentation pathway for meta,meta-cyclophane-type diarylheptanoids was proposed. Quantities of the four major cyclic diarylheptanoids in European hornbeam were determined by a validated UHPLC-DAD method for the first time. The antioxidant properties of the extracts and the isolated compounds were assessed by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. Contribution of the individual constituents to the total radical scavenging activity of the samples was evaluated by an off-line DPPH-HPLC-DAD method. This allowed the identification of gallo- and ellagitannin derivatives as the constituents being primarily responsible for the antioxidant capacity of the extracts.

Efficient access to 3′-deoxy-3′-(4-substituted-1,2,3-triazol-1-yl)-thymidine derivatives via ligand-promoted CuAAC

Herein we describe an efficient and rapid access to 3′-deoxy-3′-(4-substituted-1,2,3-triazol-1-yl)-thymidine derivatives using 1,3-dipolar cycloaddition reaction catalyzed by copper(I). Innovative conditions allow us to generate target compounds in a one-pot reaction mixing 3′-azido-3′-deoxythymidine, alkyne, copper sulfate pentahydrate, sodium ascorbate and tris(benzyltriazolylmethyl)amine in a water:tert-butanol solvent mixture. Rapid treatment of the reaction and subsequent flash purification chromatography afforded pure compounds in an overall yield of 71 – 100% . All eleven synthesized compounds were identified on the basis of their spectral data analysis ( 1 H, 13 C, 2D NMR and high-resolution mass spectra). • Innovative, rapide and efficient 1,3-dipolar cycloaddition reaction catalyzed by copper(I) was set-up. • THPTA (tris(benzyltriazolylmethyl)amine), a polydentate N -donor ligand was key in the efficiency of the reaction. • AZT-derived 1,2,3-triazole compounds are obtained in 30 min reaction at RT in a water:tert-butanol mixture. • Eleven new 3′-deoxy-3'-(4-substituted-1,2,3-triazol-1-yl)-thymidine derivatives were synthesized efficiently. • Eleven new 3′-deoxy-3'-(4-substituted-1,2,3-triazol-1-yl)-thymidine derivatives were characterized by NMR (1D, 2D) and HRMS.

The Sequence of Heavy Precipitation and Flash Flooding of 12 and 13 September 2019 in Eastern Spain. Part I: Mesoscale Diagnostic and Sensitivity Analysis of Precipitation

AbstractThe Mediterranean region is frequently affected by heavy precipitation episodes and subsequent flash flooding. An exemplary case is the heavy precipitation episode that occurred in the regions of València, Murcia, and Almería (eastern Spain) on 12 and 13 September 2019. Observed rainfall amounts were close to 500 mm in 48 h, causing seven fatalities and estimated economical losses above EUR 425 million. This case exemplifies the challenging aspects of convective-scale forecasting in the Mediterranean region, with kilometer-resolution meteorological fields required over long forecast spans. Understanding the key mesoscale factors acting on the triggering, location, and intensity of the convective systems responsible for extreme accumulations is essential to gain insight into these episodes and contribute toward their accurate hydrometeorological forecasting. Mesoscale diagnosis suggests that local and distant orography, together with air–sea fluxes, were instrumental in developing convection and intensifying precipitation rate. Sensitivity experiments confirm the role of orography in organizing the cyclonic flow over the southeast part of the western Mediterranean, and also acting as a convection-triggering mechanism. Furthermore, results highlight the role of latent heat flux from the Mediterranean Sea in enhancing convective instability at lower levels and moistening the environment. These moist feeding flows substantially contribute to increasing precipitation rates. Such high sensitivity to environmental moisture distribution naturally propagates to the sea surface temperature, which, by means of sensible and latent heat flux exchanges, dominated the evolution of convective activity for the 12–13 September 2019 episode.

Delivery of Metals and Dissolved Black Carbon to the Southern California Coastal Ocean via Aerosols and Floodwaters Following the 2017 Thomas Fire

AbstractThe Thomas Fire began on December 4, 2017 and burned 281,893 acres over a 40‐day period in Ventura and Santa Barbara Counties, making it one of California's most destructive wildfires to date. A major rainstorm then caused a flash flood event, which led to the containment of the fire. Both airborne ash from the fire and the runoff from the flash flood entered into the Santa Barbara Basin (SBB). Here, we present the results from aerosol, river, and seawater studies of black carbon and metal delivery to the SBB associated with the fire and subsequent flash flood. On day 11 of the Thomas Fire, aerosols sampled under the smoke plume were associated with high levels of PM2.5, levoglucosan, and black carbon (average: 49 μg/m3, 1.05 μg/m3, and 14.93 μg/m3, respectively) and aerosol metal concentrations were consistent with a forest fire signature. Metal concentrations in SBB surface seawater were higher closer to the coastal perimeter of the fire (including 2.22 nM Fe) than further off the coast, suggesting a dependence on continental proximity rather than fire inputs. On days 37–40 of the fire, before, during, and after the flash flood in the Ventura River, dissolved organic carbon, dissolved black carbon, and dissolved metal concentrations were positively correlated with discharge allowing us to estimate the input of fire products into the coastal ocean. We estimated rapid aerosol delivery during the fire event to be the larger share of fire‐derived metal transport compared to runoff from the Ventura River during the flood event.

Right parietotemporal activity predicts sense of agency under uncertain delays of sensory outcomes

Sense of agency is the experience of control over one's own action and its consequent outcomes. The perceived time between a motor action and its consequent sensory outcomes (e.g., a flash of light) is shorter for a voluntary than involuntary action, a phenomenon known as intentional binding, which has been used extensively as an implicit measure of sense of agency. We developed a novel task in which participants had to respond whether a flash appeared immediately or with a delay relative to their voluntary action. We found that under high, but not low, uncertainty about the perceived time between voluntary finger movement and a subsequent flash of light, a prediction signal was generated in the right inferior parietal lobule prior to motor action. This prediction signal was linked to the emergence of a sudden insight solution (colloquially referred to as "Aha!" moment) in the right superior temporal gyrus prior to response. Single-trial event-related potential analysis revealed a reliable correlation between amplitudes of premotor and preresponse activities. The results suggest the existence of a predictive mechanism under high uncertainty about the timing of the sensory consequences of a voluntary motor action. The results are in line with the optimal cue integration theory of sense of agency, which states that both predictive and postdictive agency cues are crucial for the formation of sense of agency and the weight of each type of cue (predictive or postdictive) depends on their availability and reliability.NEW & NOTEWORTHY According to the optimal cue integration theory, the formation of sense of agency relies on both predictive and postdictive agency cues and how they are weighted based on their availability and reliability. Using a novel paradigm, we show for the first time a possible existence of a prediction signal prior to voluntary movement, which appears when postdictive agency cues (i.e., the judgment of the time between voluntary movement and a subsequent flash) are not reliable.

Gamma-ray flash from a lightning leader

Lightning Terrestrial gamma-ray flashes (TGFs) are millisecond pulses of gamma rays produced by thunderstorms. Neubert et al. observed a TGF from above, using instruments on the International Space Station. High-speed photometry in optical, ultraviolet, x-ray, and gamma-ray bands allowed them to determine the sequence of events that produced the TGF. Emission from an intracloud lightning leader was followed within a millisecond by the TGF. The subsequent lightning flash produced an electromagnetic pulse, which induced expanding waves of ultraviolet emission in the ionosphere above the thunderstorm, called an elve. The authors conclude that high electric fields produced within the lightning leader generated the TGF. Science , this issue p. [183][1] [1]: /lookup/doi/10.1126/science.aax3872

Rapid and Mild Synthesis of Amino Acid N‐Carboxy Anhydrides: Basic‐to‐Acidic Flash Switching in a Microflow Reactor

AbstractPolymerization of N‐carboxy anhydrides (NCAs) is the primary process used to prepare polypeptides. The synthesis of various pure NCAs is key to the efficient synthesis of polypeptides. The only practical method that can be used to synthesize NCAs requires harsh acidic conditions that make acid‐labile substrates unusable and results in an undesired ring opening of NCAs. Basic‐to‐acidic flash switching and subsequent flash dilution technology in a microflow reactor was used to demonstrate the synthesis of NCAs. It is both rapid (0.1 s) and mild (20 °C) and includes substrates containing acid‐labile functional groups. The basic‐to‐acidic flash switching enabled both an acceleration of the desired NCA formation and avoided the undesired ring opening of NCAs. The flash dilution precluded the undesired decomposition of acid‐labile functional groups. The developed process allowed the synthesis of various NCAs which cannot be readily synthesized using conventional batch methods.

Rapid and Mild Synthesis of Amino Acid N-Carboxy Anhydrides: Basic-to-Acidic Flash Switching in a Microflow Reactor.

Polymerization of N-carboxy anhydrides (NCAs) is the primary process used to prepare polypeptides. The synthesis of various pure NCAs is key to the efficient synthesis of polypeptides. The only practical method that can be used to synthesize NCAs requires harsh acidic conditions that make acid-labile substrates unusable and results in an undesired ring opening of NCAs. Basic-to-acidic flash switching and subsequent flash dilution technology in a microflow reactor was used to demonstrate the synthesis of NCAs. It is both rapid (0.1 s) and mild (20 °C) and includes substrates containing acid-labile functional groups. The basic-to-acidic flash switching enabled both an acceleration of the desired NCA formation and avoided the undesired ring opening of NCAs. The flash dilution precluded the undesired decomposition of acid-labile functional groups. The developed process allowed the synthesis of various NCAs which cannot be readily synthesized using conventional batch methods.

Temporal recalibration of motor and visual potentials in lag adaptation in voluntary movement

Adaptively recalibrating motor-sensory asynchrony is critical for animals to perceive self-produced action consequences. It is controversial whether motor- or sensory-related neural circuits recalibrate this asynchrony. By combining magnetoencephalography (MEG) and functional MRI (fMRI), we investigate the temporal changes in brain activities caused by repeated exposure to a 150-ms delay inserted between a button-press action and a subsequent flash. We found that readiness potentials significantly shift later in the motor system, especially in parietal regions (average: 219.9 ms), while visually evoked potentials significantly shift earlier in occipital regions (average: 49.7 ms) in the delay condition compared to the no-delay condition. Moreover, the shift in readiness potentials, but not in visually evoked potentials, was significantly correlated with the psychophysical measure of motor-sensory adaptation. These results suggest that although both motor and sensory processes contribute to the recalibration, the motor process plays the major role, given the magnitudes of shift and the correlation with the psychophysical measure.

Impact of the 2013 Floods on the Incidence of Malaria in Almanagil Locality, Gezira State, Sudan.

Background: Heavy rain hit Sudan in August 2013 with subsequent flash floods in different parts of the country. This study investigated the impact of the flooding on incidence of malaria in Almanagil Locality in central Sudan.Methods: This observational retrospective study compared malaria data sets during rainfall seasons in the Almanagil Locality in the year of flooding (2013) with those of corresponding rainfall seasons of previous two non-flood years (2011 and 2012).Results: A marked increase of new malaria cases and incidence rate was observed in the 13 sentinel malaria notification sites in the locality (IR increased from 6.09 per 100,000 person­days in 2011 [95 % CI: 5.93-6.26] and 6.48 in 2012 [95 % CI: 6.31-6.65] to 8.24 in 2013 [95 % CI: 8.05-8.43] ; P< 0.0001), with a peaking of the incidence rate in the under-5-years age group (IR for this age group jumped from 9.80 per 100,000 person­days in 2011 [95 % CI: 9.29­10.32] and 10.00 in 2012 [95 % CI: 9.52­10.49] to 15.02 in 2013 [95 % CI: 14.41­15.64]). A noticeable increase in the slide positivity rate (P< 0.0001) was observed in the 12-week period of 2013 (SPR = 20.86% [95 % CI: 20.40 ­21.32%]) compared with the same periods in 2011 (SPR = 8.72% [95 % CI: 8.36 ­9.08%]) and 2012 (SPR = 12.62% [95 % CI: 12.24 ­13.01%]), with a more marked rise of the SPR in the under-5-year age group. Hospital data showed increase in both the inpatient and outpatient incidence proportions in the study period of 2013 compared to those of the years 2011 and 2012. Hospital OPD incidence proportion in 2013 was 19.7% (95% CI: 19.24­20.18%) compared to 12.85% (95% CI: 12.48­13.23%) in 2011, and 12.16% (95% CI: 11.82­12.51%) in 2012. The < 5 year old groups were responsible for the overall rise in the proportion of malaria cases in 2013 , particularly the < 1 year old group which more than doubled in the 2013 period compared to both 2011 and 2012 periods (Age­specific proportion of the outpatient malaria cases of the < 1 year old group in 2013 was19.5% [95% CI: 18.5­20.6%] compared to 7.7% [95% CI: 6.9­8.6%] in 2011 and 8.1% [95% CI: 7.3­8.9%] in 2012. Incidence proportion of severe malaria cases (inpatients) increased to 22.5 % (95 % CI: 21.5 to 23.6 %) in the study period of 2013 compared to 19.8 % (95 % CI: 18.6 to 21.0 %) in 2011 and 18.4 % (95 % CI: 17.4 to 19.5) in 2012. The increase in the proportion of severe malaria cases was mainly due to a higher proportion of children < 5 years of age and especially to a higher proportion of children < 1 year of age.Conclusion: The study revealed a significant increase in the incidence rate of malaria in Almanagil Locality following the flash flood of August 2013. The flooding had the highest impact on the malaria incidence of the under-5-years age group, and particularly of the under-1-year age group.Keywords: Flood, Flooding, Malaria, Disaster, Sudan, Gezira, Almanagil