Hull Size Research Articles

Analysis of the role of the rice metallothionein gene OsMT2b in grain size regulation

Seed size is one of the three main characteristics determining rice yield. Clarification of the mechanisms regulating seed size in rice has implications for improving rice yield. Although several genes have been reported to regulate seed size, most of the reports are fragmentary. The role of metallothioneins (MTs) in regulating seed size remains unknown. Here, we found that OsMT2b was expressed in both spikelets and developing seeds. OsMT2b-overexpression lines had large and heavy seeds, and RNAi (RNA interference) lines had small and light seeds. Scanning electron microscopy (SEM) observations revealed that OsMT2b regulated spikelet hull size by affecting cell expansion in the outer epidermis. Histological analysis indicated that OsMT2b affected the number of cells in the cross-section of spikelet hulls, which affected seed size. The fresh weight of seeds was consistently higher in OsMT2b-overexpression lines than in seeds of the wild-type (WT) and RNAi lines from 6 DAP (days after pollination) until maturity, indicating that OsMT2b affected seed filling. Reverse transcription-quantitative PCR (RT-qPCR) analyses revealed that OsMT2b regulates the expression of reactive oxygen species scavenging-related genes involved in seed size regulation. In conclusion, our results indicated that OsMT2b positively regulates seed size, which provides a novel approach for regulating seed size with genetic engineering technology.

Carotid body ablation restores astrocyte/microglia morphology in the NTS and reduces hypertension following long-term intermittent hypoxia

Chronic intermittent hypoxia (CIH) heightened carotid body (CB) chemosensory discharges, which contributes to hypertension development. Previously, we reported that CB ablation significantly reduced blood pressure after 21 days of CIH; however, whether CB-mediated glial cell activation in the caudal Nucleus of the Solitary Tract (cNTS) following long-term CIH contribute to maintain high blood pressure and enhanced ventilatory chemoreflex remains unknown. To test this hypothesis, we exposed male C57BL6 mice to CIH (5% FIO2, 12 times/h, 8 h/day) for 60 days. At 45 days of CIH, CBs were selectively denervated, and animals returned to CIH for 15 more days. At the end of the experimental protocol, we measured arterial blood pressure, hypoxic ventilatory response (HVR) in awake mice and characterized astrocyte and microglia morphological features using Sholl analysis. CIH induces hypertension (MABP: 83.47±1.39 vs. 95.00±2.18 mmHg; Sham vs. CIH), increases the HVR (1.69±0.17 vs. 4.31±0.87 ΔVE/min; Sham vs. CIH), modify cNTS astrocytes phenotype (N° of branches: 13.01±0.66 vs. 11.31±0.52; cable length: 181.00±8.90 vs 148.10±1.48 μm, convex hull: 788.10±37.60 vs. 584.30±23.75 μm3; Sham vs. CIH), and microglia arborization (N° of branches: 196.10±8.35 vs. 376.30±16.80; cable length: 667.4±29.63 vs. 1267±60.47 μm, convex hull: 6177±362 vs. 9721±564 μm3; Sham vs. CIH). Importantly, CB denervation normalized the elevated blood pressure (MABP: 83.47±1.38 mmHg; CIHd), the altered peripheral chemoreflex response (HVR: 1.63±0.43 ΔVE/min; CIHd) and morphological changes in astrocytes (N °of branches: 17.23±0.88, cable length: 231.70±12.87, convex hull: 982.70±55.55 μm3) and microglia located in the cNTS (N° of branches 126.20±13.34; cable length: 126.2±13.3, Convex hull size: 3584±380 μm3; CIHd). Present results suggest that CBs play a crucial role in the maintenance of high arterial pressure and respiratory alterations induced by long-term CIH and may contribute to the formation of a neuroinflammatory niche at the cNTS by modifying glial cell activity. Supported by Fondecyt Grants 1211443 and 1220950. This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Three-dimensional diagnosis of lean premixed turbulent swirl flames using tomographic background oriented Schlieren

The necessity of minimizing NOx emissions drives the pursuit of ultra-lean premixed combustion in aeroengines and gas turbines, characterized by susceptibility to combustion instabilities. To tackle this issue, swirling flow design is widely incorporated into lean premixed combustor design, enhancing flame stability, and shortening flame length. This study utilizes the tomographic background-oriented Schlieren (TBOS) to reconstruct the spatial distribution of the refractive index gradient of lean premixed turbulent swirl flames with an aeroengine combustor configuration. A parametric study of the TBOS reconstruction quality is conducted, and the results reveal that view sparseness primarily degrades the reconstruction quality compared to the specific iterative algorithm used. The classic visual hull approach is explored to address this challenge, highlighting the significance of visual hull size. Furthermore, to improve the reconstruction quality, a posterior support constraint method is proposed, involving the removal of voxels of nearly constant refractive index within the central volume surrounded by flames. Results demonstrate that implementing this posterior support constraint further improves the reconstruction quality of lean premixed turbulent swirl flames. Finally, the robustness of this posterior support constraint method is validated by introducing high-level noise to the light deflection data, showcasing the potential of combining the dedicated designed visual hull and proposed posterior support constraint in addressing the view sparseness challenge for TBOS measurements.

Automation of vessel slamming avoidance processes

The object of the research is the processes of slamming automatic avoidance when the vessel is sailing in a storm. During stormy sailing, the vessel is subjected to external influences from wind and waves, which lead to strong dynamic loads on the hull, increase in heel and trim angles, flooding of the deck. The vessel's speed decreases, its controllability deteriorates. Slamming is one of the most dangerous phenomena in storm sailing. The appearance of slamming depends on many factors: the size and shape of the vessel's hull, the draft of the bow, the state of the sea, the vessel's course and speed. Slamming is characterized by impacts of the bow and the bottom of the vessel's hull against the water when moving towards waves, the length of which is approximately equal to the length of the vessel. Impacts are accompanied by body shaking, due to a sharp increase in the load on the bottom, and a slowly fading vibration. Hydrodynamic shocks on the bottom and general vibration are the reasons for the violation of the local and general strength of the hull. Slamming and other dangers of stormy sailing are the cause of strong psycho-emotional stress of boatmen, contribute to the accumulation of fatigue, which is a prerequisite for accidents. In the article, a method of automatic control of the vessel to prevent slamming was developed. The obtained results are explained by the use of an on-board computer, the construction of a dangerous area of slamming in on-board computer, the use of a gradient method of finding the optimal trajectory in time of the phase point output from the dangerous area, and the maintenance of the optimal trajectory by means of an automatic control system. The use of the developed method allows you to automatically avoid slamming, reduce the influence of the human factor on control processes, reduce crew fatigue, reduce the risks of losing the ship and cargo, and increase the safety of navigation. The developed method can be used on vessels, provided it is integrated into the existing automated system of the on-board computer to solve the problem of automatic avoidance of slamming during stormy sailing

Role of Port Tugs in Ship-Borne Emissions: An Analysis in Turkey's Izmit Bay

Thanks to the awareness created by the concrete effects of global warming and climatic irregularities, concepts such as carbon emissions, polluting gases, internal combustion engines, energy efficiency are gaining more and more importance in our lives globally. In this context, the maritime sector, which provides the transfer of 90% of global trade, has become the center of attention with its ships boasting huge machinery and has also been a subject of exhaust emission studies. The fact that approximately 70% of ship emissions occur in coastal areas requires more scrutiny of ships operating in these areas. Providing docking and departing services for ports, having small hull sizes compared to other ships but featuring big machinery in terms of power output (kW), port tugboats are a serious source of emissions. As a first in this literature, the present study aimed to make a 3-month emission inventory of port tugs in Izmit Bay, where Turkey’s largest shipping activities take place, and to compare it with emission studies for other ships. In the study period, port tugs’ emissions of CO2, NOX, SOX, VOC, PM, CO were calculated to be 7,398.88 tonnes, 121.09 tonnes, 66.43 tonnes, 2.13 tonnes, 4.27 tonnes, and 5.77 tonnes, respectively. This suggests that port tugs have a significant place among ship types in terms of producing exhaust emissions.

Design method of combined stiffened pressure hulls with variable-curvature characteristic

This study presents a combined pressure hull design method with variable-section ribs. This method for determining the length-radius ratio of the pressure hull's bearing unit is derived based on the stiffness-matching characteristic of the shell and stiffener. The bearing mechanism of variable curvature stiffened shell is discussed through theoretical derivation and numerical simulation. The design scheme of variable cross-section and the equal-stiffness rib is proposed to address the limitations of outer envelope size and inner space utilization of the pressure hull. Its buckling load is determined by the energy method. The design approach for a new type of stiffened pressure hull is summarized. In addition, the method is verified by the design example and the experiment. The results revealed that the combined variable curvature shells are a superior pressure hull configuration. Compared to the cylindrical stiffened shell, the buckling load of the pressure hull with variable cross-section ribs can be improved significantly (about 26.7%). At the same time, space utilization remains at the original level. The stiffened design technique described in this research based on elastic buckling theory can accurately determine the length-radius ratio of the bearing unit, relying on the design objective with high feasibility.

CORRELATIONS OF GPS-BASED COMMUNITY MOBILITY METRICS BETWEEN PERSONS WITH DEMENTIA AND FAMILY CAREGIVERS

Abstract Currently, the majority of dementia care is provided at home by informal caregivers. Most informal caregivers share a routine with their loved ones and change their activity patterns to adapt to a new routine of persons with dementia (PWDs). Given the dementia caregiving context, caregivers’ mobility behaviors and PWDs’ mobility may be positively associated. This study aimed to characterize patterns of GPS-derived community mobility in dementia dyads and examine relationships between PWDs’ and caregivers’ mobility patterns. Six dyads wore a GPS data logger inside and outside the home for 8-11 days. Twelve participants generated valid GPS track files (N=110). Four temporal and spatial mobility metrics were derived from GPS data (total distance, time use, median speed, and convex hull area). Then we calculated Pearson correlation coefficients between PWDs and their caregivers over all tracks. All dyads made active out-of-home trips, indicated by mean daily distance (range: 6,198 - 115,592m for PWDs; 5,125 - 108,857m for caregivers). Median speed of movement ranged from 0.09 to 1.29 km/hour for PWDs, and from 0.21 to 0.97 km/hour for caregivers. The mean size of convex hull over the monitoring period indicates a limited space usage level in both PWDs and caregivers, meaning restricted community mobility despite relatively large distance trips. The correlation coefficient was positive and significant for each metric (r = 0.70-0.97, p < .001). These results suggest substantial agreement in the mobility metrics between PWD and their caregivers, indicating a high level of dyadic effects of a partner’s experience of community mobility.

Performance Evaluation of the Newly Operational NDBC 2.1-m Hull

Abstract The importance of quantifying the accuracy in wave measurements is critical to not only understand the complexities of wind-generated waves, but imperative for the interpretation of implied accuracy of the prediction systems that use these data for verification and validation. As wave measurement systems have unique collection and processing attributes that result in large accuracy ranges, this work quantifies bias that may be introduced into wave models from the newly operational NOAA National Data Buoy Center (NDBC) 2.1-m hull. Data quality consistency between the legacy NDBC 3-m aluminum hulls and the new 2.1-m hull is compared to a relative reference, and provides a standardized methodology and graphical representation template for future intrameasurement evaluations. Statistical analyses and wave spectral comparisons confirm that the wave measurements reported from the NDBC 2.1-m hulls show an increased accuracy from previously collected NDBC 3-m hull wave data for significant wave height and average wave period, while retaining consistent accuracy for directional results, purporting that hull size does not impact NDBC directional data estimates. Spectrally, the NDBC 2.1-m hulls show an improved signal-to-noise ratio, allowing for increase in energy retention in the lower-frequency spectral range, with an improved high-frequency spectral accuracy above 0.25 Hz within the short seas and wind chop wave component regions. These improvements in both NDBC bulk and spectral data accuracy provide confidence for the wave community’s use of NDBC wave data to drive wave model technologies, improvements, and validations.

Low-Cost Heaving Single-Buoy Wave-Energy Point Absorber Optimization for Sardinia West Coast

This work presents the Water Energy Point Absorber (WEPA), which is a heaving single-buoy point absorber optimized for a specific site off the west coast of Sardinia Island. The aim of the study is to present the optimization process undertaken to identify the best configuration in terms of performance and cost. The optimization is carried out thanks to a simulation tool developed in Matlab-Simulink environment and verified through to the commercial software Orcaflex. Simulations are performed in the time domain with the installation site’s waves as input. The hydrodynamics parameters are computed thanks to the commercial software Ansys Aqwa and given to the model as input. The yearly energy production is computed as output for each configuration. Several parametric analyses are performed to identify the optimal Power Take Off (PTO) and buoy size. Among the main findings, it shall be mentioned that the PTO-rated torque has a strong influence on the energy production, higher PTO-rated torque proved to have better performance. The optimal hull size is strictly related to the incoming waves, and for the given site the smaller hulls are performing better than larger ones. The hull height, hull mass and hull draft have little impact on productivity. Finally, a comprehensive techno–economic analysis is performed, showing that the best configuration can be identified only after a detailed feasibility study and rigorous cost analysis.

Mobility enhancement among older adults 75\u2009+\u2009in rural areas: Study protocol of the MOBILE randomized controlled trial

BackgroundMaintaining mobility in old age is crucial for healthy ageing including delaying the onset and progress of frailty. However, the extent of an individuals´ mobility relies largely on their personal, social, and environmental resources as outlined in the Life-Space Constriction Model. Recent studies mainly focus on facilitating habitual out-of-home mobility by fostering one type of resources only. The MOBILE trial aims at testing whether tablet-assisted motivational counselling enhances the mobility of community-dwelling older adults by addressing personal, social, and environmental resources.MethodsIn the MOBILE randomized controlled trial, we plan to enrol 254 community-dwelling older adults aged 75 and older from Havelland, a rural area in Germany. The intervention group will receive a tablet-assisted motivational counselling at the participant´s home and two follow-up telephone sessions. Main focus of the counselling sessions lays on setting and adapting individual mobility goals and applying action planning and habit formation strategies by incorporating the personal social network and regional opportunities for engaging in mobility related activities. The control group will receive postal general health information. The primary mobility outcome is time out-of-home assessed by GPS (GPS.Rec2.0-App) at three points in time (baseline, after one month, and after three months for seven consecutive days each). Secondary outcomes are the size of the GPS-derived life-space convex hull, self-reported life-space mobility (LSA-D), physical activity (IPAQ), depressive symptoms (GDS), frailty phenotype, and health status (SF-12).DiscussionThe MOBILE trial will test the effect of a motivational counselling intervention on out-of-home mobility in community-dwelling older adults. Novel aspects of the MOBILE trial include the preventive multi-level intervention approach in combination with easy-to-use technology. The ecological approach ensures low-threshold implementation, which increases the benefit for the people in the region.Trial registrationThe MOBILE trial is prospectively registered at DRKS (Deutsches Register Klinischer Studien, German Registry of Clinical Trials) DRKS00025230. Registered 5 May 2021.

Analysis of wave fluctuation on underwater acoustic communication based USV

In the scenario of UAC(Underwater Acoustic Communication) between the USV(Unmanned Surface Vehicle) and underwater node, the affection originated from sea surface random fluctuation to UAC system stability cannot be neglected due to the small size of hull and the shallow draft, especially when USV is sailing near sea surface. The experimental results indicate that the random fluctuation of the sea surface has several influences both on signal propagation and multi-channel structure, and they are difficult to describe quantitatively. Following the research of?marine environment – channel characteristics – underwater acoustic communication’, this paper proposes a shallow sea wave spectrum model(USV_SW) to design UAC system based on measured data including the environment parameters, wind speed, wind direction, and real-time water depth. Moreover, the verification of elevation is presented between the proposed USV_SW model and CORS_GPS(Continuously Operating Reference Stations GPS) data collected on USV. Therefore, we calculated the average acoustic reflection coefficient of random fluctuation interface which is applied for the following simulation analysis of vertical and horizontal channels influenced by interface fluctuation. Simulation results show that the horizontal channel is affected more by random interface fluctuation and its characteristic signal space–time fluctuation is noteworthy in bad sea conditions. The analysis of the random fluctuation interface on the channel structure provides data and theoretical support for the design of the USV underwater acoustic communication scheme.

MEMS-based wave buoy: Towards short wind-wave sensing

Low-cost commercial micro-electro-mechanical system (MEMS)-based inertial motion unit is used for sea surface wave measurements. A buoy is developed based on the capacitive silicon-based accelerometer–gyroscope–magnetometer sensor with radically simplified architecture allowing a significant reduction of the buoy hull size down to 14-cm diameter and hence increased high-frequency sensitivity. The proposed buoy design is suitable for short-term manual wave measurements with minimal deployment–recovery efforts and/or experiments where knowledge of the high-frequency part of the spectrum is preferable. The buoy data is validated in a field experiment at the Black Sea stationary research platform using reference measurements of the six-wire resistive wave gauge. The strapped-down buoy measurements are transformed into the georeferenced buoy tilts and vertical acceleration using small wave slope approximation. The classical (Longuet-Higgins et al., 1961) approach is used for directional wave spectra estimation. Under 1 to 15 m/s wind speed, pure wind and mixed sea conditions, the significant wave height, wave peak period, wave direction, and spectral width are well reproduced by the buoy. The buoy geometric cut-off frequency, about 2.5 Hz, corresponding to wavelength twice the hull diameter, is at least 2.5 times better than that of commercially available buoys. The sub-peak low-frequency noise, typical for accelerometer-derived spectra, is wind-dependent and thus is clearly not the intrinsic sensor noise, but rather results from the buoy non-linear response to the waves. The detected high-frequency (4<f<80Hz) spectrum tail also depends on the wind speed in accord with the short-wave wind-driven wave spectrum model. The observed high-frequency sensitivity may be useful for short-wave sensing beyond the geometric cut-off frequency with MEMS-based sensors.

Retention of tree-related microhabitats is more dependent on selection of habitat trees than their spatial distribution

Habitat trees, which provide roosting, foraging and nesting for multiple taxa, are retained in managed forests to support biodiversity conservation. To what extent their spatial distribution influences provisioning of habitats has rarely been addressed. In this study, we investigated whether abundance and richness of tree-related microhabitats (TreMs) differ between habitat trees in clumped and dispersed distributions and whether the abundance of fifteen groups of TreMs is related to tree distribution patterns. To identify habitat trees, we quantified TreMs in temperate mountain forests of Germany. We determined clumping (the Clark–Evans index), size of the convex hull, diameter at breast height, as well as altitude, slope and aspect of sites for their possible influence on TreMs. We additionally determined the difference in TreM abundance and richness among four options of selecting five habitat trees per ha from 15 candidates: (a) the most clumped trees, (b) five randomly selected and dispersed trees, (c) the single tree with highest abundance or richness of TreMs and its four closest neighbors and (d) a “reference selection” of five trees with known highest abundance or richness of TreMs irrespective of their distribution. The degree of clumping and the size of the convex hull influenced neither the abundance nor richness of TreMs. The reference selection, option (d), contained more than twice the number of TreMs compared to the most clumped, (a), or random distributions, (b), of five habitat trees, while option (c) assumed an intermediate position. If the goal of habitat tree retention is to maximize stand-level abundance and richness of TreMs, then it is clearly more important to select habitat trees irrespective of their spatial pattern.

The C2H2 zinc-finger protein LACKING RUDIMENTARY GLUME 1 regulates spikelet development in rice

Rice (Oryza sativa) spikelets are a unique inflorescence structure and their development directly determines grain size and yield. Although many genes related to spikelet development have been reported, the molecular mechanisms underlying this process have not been fully elucidated. In this study, we identified a new recessive rice mutant, lacking rudimentary glume 1 (lrg1). The lrg1 spikelets only formed one rudimentary glume, which, along with the sterile lemmas, was homeotically transformed into lemma-like organs and acquired lemma identity. The transition from the spikelet to the floral meristem was delayed in the lrg1 mutant, resulting in the formation of an ectopic lemma-like organ between the sterile lemma and the terminal floret. In addition, we found that the abnormal lrg1 grain phenotype resulted from the alteration of cell numbers and the hull size. LRG1 encodes a ZOS4-06-C2H2 zinc-finger protein with the typical EAR motifs, and is expressed in all organs and tissues. LRG1 localizes to the nucleus and can interact with the TOPLESS-RELATED PROTEINs (TPRs) to repress the expressions of their downstream target genes. Taken together, our results reveal that LRG1 plays an important role in the regulation of spikelet organ identity and grain size.

Entropy Evaluation Method for Sandstone Uranium Reservoir Characteristics Based on Convex Hull Search

The continuity and homogeneity of sandstone uranium deposits are inherent characteristics that affect in situ leaching performance indexes and have important guiding effects on the optimization of mining design. In this work, we propose a spatial information entropy calculation method based on a convex hull search strategy to quantitatively evaluate the geological characteristics of uranium deposits. We use the 3-D block model of sandstone-hosted uranium deposits as hard data. First, we use the Alpha-Shapes algorithm to calculate the convex hull of the space area where various types of unit blocks are located. Second, we formulate a suitable multi-point configuration based on the convex hull size. Then, we use the multi-point density function. Scanning the convex hull point cloud establishes a probability density function to calculate the local information entropy of various sub-regions. Finally, the local spatial information entropy is aggregated using addition and multiplication to obtain the joint spatial information entropy of the entire evaluation area. A series of parameter sensitivity and performance analysis experiments prove the stability of the method and the accuracy of the quantitative and homogeneous evaluations of the complex geological conditions. In order to solve the problem of the difference between the designed production capacity and actual production capacity of a uranium deposit, we use a new method to evaluate the homogeneity and continuity of the lithology and grade of the deposit. The new method and evaluation conclusions can be used for the automation and understanding of future engineering optimization processes.

Sucrose Synthase Enhances Hull Size and Grain Weight by Regulating Cell Division and Starch Accumulation in Transgenic Rice.

Grain size and weight are two important determinants of grain yield in rice. Although overexpression of sucrose synthase (SUS) genes has led to several improvements on cellulose and starch-based traits in transgenic crops, little is reported about SUS enhancement of hull size and grain weight in rice. In this study, we selected transgenic rice plants that overexpressed OsSUS1-6 genes driven with the maize Ubi promoter. Compared to the controls (wild type and empty vector line), all independent OsSUS homozygous transgenic lines exhibited considerably increased grain yield and grain weights. Using the representative OsSUS3 overexpressed transgenic plants, four independent homozygous lines showed much raised cell numbers for larger hull sizes, consistent with their enhanced primary cell wall cellulose biosynthesis and postponed secondary wall synthesis. Accordingly, the OsSUS3 transgenic lines contained much larger endosperm volume and higher starch levels than those of the controls in the mature grains, leading to increased brown grain weights by 15–19%. Hence, the results have demonstrated that OsSUS overexpression could significantly improve hull size and grain weight by dynamically regulating cell division and starch accumulation in the transgenic rice.

Analytic Comparisons of Shipbuilding Competitiveness between China and Korea

Purpose - This research empirically proves that global shipbuilding industry leadership has moved to China from Korea. Design/Methodology - Competitiveness is measured by AHP for the weights of comprehensive competitiveness, which is the output mixture of three attributive factors: shipbuilding technology, shipbuilding contract price, and export credit. Findings - China is far ahead of Korea for standard vessels such as bulkers and containerships with competitiveness weights of 0.762 and 0.612, respectively, against 0.238 and 0.388 of Korea. Korea is maintaining its competitiveness only in LNG carriers (174k CBM) with a competitiveness weight 0.621. China and Korea have similar competitiveness for chemical carriers, complex vessels with a small hull size. The sources of Chinese competitiveness are shipbuilding contract price and export credit. With the majority share of standard vessel types in the world fleet, China will hold a bigger market share than Korea in the global shipbuilding industry in the forthcoming years. Implications - The swing factors of market power are shipbuilding technology and contract price. If China fails to further develop shipbuilding technology for shipowners worried about the reliability of the Chinese-built vessels, shipowners may swing back to Korea. The rising Chinese labor cost will expedite this swing in the forthcoming competition. Originality/value - To the best of the author’s knowledge, this is the first paper that quantitatively examines the competitiveness of shipbuilding between China and Korea by comparing attributive factors for competitiveness.

Articulatory Range of Movement in Individuals With Dysarthria Secondary to Amyotrophic Lateral Sclerosis.

The current study examined overall articulatory range of movement (ROM) in individuals with amyotrophic lateral sclerosis (ALS). Differential involvement of articulators was also tested using articulatory working space in individuals with varying degrees of dysarthria severity and in typically aging individuals. A strong association between overall articulatory ROM and severity measures among individuals with ALS was hypothesized. In addition, it was hypothesized that differential involvement of articulators would be detected using overall articulatory ROM measures. Twenty-two speakers with dysarthria secondary to ALS and 22 typically aging speakers participated. Speech intelligibility and speaking rate were used as indices of severity. Movement range and overall articulatory working space area (convex hull) of the tongue, lower lip, and jaw were each measured by electromagnetic articulography while the speakers produced the Rainbow Passage. Tongue convex hull size was significantly correlated with both indices of severity. A significant interaction between articulators and groups was observed. Individuals with severe dysarthria had reduced tongue convex hull size and exaggerated lower lip convex hull size. ROM in the anterior-posterior dimension showed a more notable differential involvement pattern than ROM in the superior-inferior dimension. Results in the area under a receiver operating characteristic curve analysis revealed group-specific ROM sensitivity. The findings indicate that tongue ROM is reduced in individuals with more severe dysarthria when estimated using a standardized paragraph containing all American English phonemes. The articulatory working space measure could be useful for estimating speech dysfunction in ALS. ROM of the tongue decreases, but ROM of the lower lip and jaw each increase in individuals with severe dysarthria. Differential involvement of the articulators in the anterior-posterior dimension needs to be further investigated.

Design optimization of hull size for spar-based floating offshore wind turbines

A newly evolving concept in utility-scale floating wind turbines is investigated through design optimization. The ideal hull length is selected from seven new designs, based on optimizing the trade-off between minimizing structural weight and maximizing electricity harvest. The seven new spar-buoy designs have drafts ranging from 62 to 120 m. Each floater hull has been developed in conformance with industry-standard structural guide API Bulletin 2U. Performance is assessed with the Loose software using time-domain analysis and irregular winds and waves. The simulation method is based on multi-body theory in Euler space, which does not rely on small-angle assumptions. Nonlinear hydrostatic restoring forces and moments are derived for large rotational angles in the pitch-roll-yaw Euler angle sequence. Environmental forcing by wind is computed using aero-elastic theory. A new individual pitch control (IPC) method based on DISCON control routine (Jonkman) is investigated as a possible means to improve generating efficiency. The pitch angle of each blade is individually controlled relative to a mean angle computed by DISCON to maintain the ideal angle of attack by removing the angle change caused by inclining tower. A comparison of the generating efficiency between IPC and traditional collective pitch control shows that IPC is not an effective way to increase output power.

Identification of a novel SPLIT-HULL (SPH) gene associated with hull splitting in rice (Oryza sativa L.).

The split-hull phenotype caused by reduced lemma width and low lignin content is under control of SPH encoding a type-2 13-lipoxygenase and contributes to high dehulling efficiency. Rice hulls consist of two bract-like structures, the lemma and palea. The hull is an important organ that helps to protect seeds from environmental stress, determines seed shape, and ensures grain filling. Achieving optimal hull size and morphology is beneficial for seed development. We characterized the split-hull (sph) mutant in rice, which exhibits hull splitting in the interlocking part between lemma and palea and/or the folded part of the lemma during the grain filling stage. Morphological and chemical analysis revealed that reduction in the width of the lemma and lignin content of the hull in the sph mutant might be the cause of hull splitting. Genetic analysis indicated that the mutant phenotype was controlled by a single recessive gene, sph (Os04g0447100), which encodes a type-2 13-lipoxygenase. SPH knockout and knockdown transgenic plants displayed the same split-hull phenotype as in the mutant. The sph mutant showed significantly higher linoleic and linolenic acid (substrates of lipoxygenase) contents in spikelets compared to the wild type. It is probably due to the genetic defect of SPH and subsequent decrease in lipoxygenase activity. In dehulling experiment, the sph mutant showed high dehulling efficiency even by a weak tearing force in a dehulling machine. Collectively, the results provide a basis for understanding of the functional role of lipoxygenase in structure and maintenance of hulls, and would facilitate breeding of easy-dehulling rice.