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Precision hill-drop direct seeding using mechanical drilling is a unique direct seeding technique employed in south China that offers advantages such as excellent grain yield and high lodging resistance. Improving yield and lodging-related traits is essential for efforts to improve mechanically direct-seeded rice (MDSR) production. Seeding rates (SR) and nitrogen (N) fertilization rate are two of the main factors affecting grain yield and lodging resistance under MDSR production. However, little information about double-season MDSR production in south China is available. Here, we evaluated yield and lodging risk for two rice cultivars Huanghuazhan, HHZ, lodging-resistant; Xiangyaxiangzhan, XYXZ, lodging-susceptible across two consecutive growing seasons under two under two seeding rates (LSR, 30 cm × 18 cm; HSR, 30 cm × 12 cm) and three N fertilization rates (N1 = 100 kg ha−1, reduced N; N2 = 150 kg ha−1, normal N; and N3 = 200 kg ha−1, enhanced N). We found that increased SR and N fertilization rate improved grain yield and increased lodging risk. SR and N were consistently and positively related to plant height (PH), gravity center height (GCH), the length from the broken basal internode to the panicle tip (SL), the fresh plant weight of the plant part above the broken point (FW), and the length of the two basal internodes. SR and N decreased breaking force (F) and breaking strength (BM), driving increased lodging risk as reflected by increases in lodging index (LI) values. Culm diameter (CD) and culm wall thickness (CWT) did not respond consistently to SR and N treatments. Correlation analysis revealed that PH, GCH, the length of first and second basal internodes, FW, and bending moment for the whole plant (WP) were positively correlated with LI, while F and BM were negatively associated with LI. These findings suggest that the increased lodging risk resulting from high SR could be mitigated by applying appropriate rates of N; that is, this work suggests that grain yield can be maximized and lodging risk minimized by increasing SR while decreasing N fertilization rate. Seasonal differences in the effects of SR and N fertilization should be considered to achieve a high grain yield and maintain high lodging resistance. Our study suggests that increasing SR and decreasing N fertilization can enhance rice grain yield while improving lodging resistance for both varieties. Optimizing grain yield by increasing SR while reducing lodging risk by lowering N application rates may maintain lodging resistance and improve grain yield. [ABSTRACT FROM AUTHOR]

Does severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection during ovarian stimulation affect assisted reproductive technology outcomes? This retrospective cohort study conducted at the Reproductive Medicine Centre of The First Affiliated Hospital of Anhui Medical University aimed to assess the effects of acute SARS-CoV-2 infection during IVF on treatment outcomes and the reproductive system. The study included 151 treatment cycles involving couples with coronavirus disease 2019 (COVID-19) during ovarian stimulation, along with 224 cycles of non-infected couples as a control group. Clinical characteristics and laboratory parameters were analysed, including total gonadotrophin dosage, duration of ovarian stimulation, number of oocytes retrieved, fertilization method, fertilization rate, and number of blastocyst embryos available. Forty-six follicular fluid samples, 38 semen samples and 78 embryo culture medium samples from patients with COVID-19 were tested for SARS-CoV-2 RNA using reverse transcription polymerase chain reaction assay. The treatment and control groups showed similar cycle characteristics, including fertilization method, total gonadotrophin dosage and duration of ovarian stimulation. The mean number of oocytes retrieved per cycle and rate of mature oocytes in intracytoplasmic sperm injection cycles were comparable. No significant difference was observed in the total number of blastocyst embryos available between the groups. Furthermore, no SARS-CoV-2 RNA was detected in any of the samples of patients with COVID-19. In conclusion, acute SARS-CoV-2 infection during ovarian stimulation does not have a significant impact on IVF treatment outcomes. Additionally, no risk to the reproductive system was observed in patients infected with SARS-CoV-2. Therefore, individuals with asymptomatic or mild COVID-19 can safely continue IVF treatment. Future research is needed to investigate the long-term effects of COVID-19 on fertility and reproductive outcomes. [ABSTRACT FROM AUTHOR]

Stem mechanical strength is an important agricultural quantitative trait that is closely related to lodging resistance in rice, which is known to be reduced by fertilizer with higher levels of nitrogen. To understand the mechanism that regulates stem mechanical strength in response to nitrogen, we analysed stem morphology, anatomy, mechanical properties, cell wall components, and expression of cell wall-related genes, in two varieties of japonica rice, namely, Wuyunjing23 (lodging-resistant variety) and W3668 (lodging-susceptible variety). The results showed that higher nitrogen fertilizer increased the lodging index in both varieties due to a reduction in breaking strength and bending stress, and these changes were larger in W3668. Cellulose content decreased slightly under higher nitrogen fertilizer, whereas lignin content reduced remarkably. Histochemical staining revealed that high nitrogen application decreased lignin deposition in the secondary cell wall of the sclerenchyma cells and vascular bundle cells compared with the low nitrogen treatments, while it did not alter the pattern of cellulose deposition in these cells in both Wuyunjing23 and W3668. In addition, the expression of the genes involved in lignin biosynthesis, OsPAL, OsCoMT, Os4CL3, OsCCR, OsCAD2, OsCAD7, OsCesA4, and OsCesA7, were also down-regulated under higher nitrogen conditions at the early stage of culm growth. These results suggest that the genes involved in lignin biosynthesis are down-regulated by higher nitrogen fertilizer, which causes lignin deficiency in the secondary cell walls and the weakening of mechanical tissue structure. Subsequently, this results in these internodes with reduced mechanical strength and poor lodging resistance. [ABSTRACT FROM AUTHOR]

Objective: To study the mechanism of the no-reflow phenomenon using coronary angiography (CAG) and intravascular ultrasound (IVUS). Methods: A total of 120 patients with acute myocardial infarction (AMI) who successfully underwent indwelling intracoronary stent placement by percutaneous coronary intervention (PCI). All patients underwent pre- and post-PCI CAG and pre-IVUS. No-reflow was defined as post-PCI thrombolysis in myocardial infarction (TIMI) grade 0, 1, or 2 flow in the absence of mechanical obstruction. Normal reflow was defined as TIMI grade 3 flow. The pre-operation reference vascular area, minimal luminal cross-sectional area, plaque cross-sectional area, lesion length, plaque volume and plaque traits were measured by IVUS. Results: The no-reflow group was observed in 14 cases (11.6%) and normal blood-flow group in 106 cases (89.4%) based on CAG results. There was no statistically significant difference in the patients’ medical history, reference vascular area (no-flow vs. normal-flow; 15.5 ± 3.2 vs. 16.2 ± 3.3, p> 0.05) and lesion length (21.9 ± 5.1 vs. 19.5 ± 4.8, p> 0.05) between the two groups. No-reflow patients had a longer symptom onset to reperfusion time compared to normal blood-flow group [(6.6 ± 3.1) h vs (4.3 ± 2.7) h; p< 0.05] and higher incidence of TIMI flow grade< 3 (71.4% vs 49.0%, p< 0.05). By IVUS examination, the no-reflow group had a significantly increased coronary plaque area and plaque volume compared to normal blood-flow group [(13.7 ± 3.0) mm2 vs (10.2 ± 2.9) mm2; (285.4 ± 99.8) mm3 vs (189.7 ± 86.4) mm3; p< 0.01]. The presence of IVUS-detected soft plaque (57.1% vs. 24.0%, p< 0.01), eccentric plaque (64.2% vs. 33.7%, p< 0.05), plaque rupture (50.0% vs. 21.2%, p< 0.01), and thrombosis (42.8% vs. 15.3%) were significantly more common in no-reflow group. Conclusion: There was no obvious relationship between the coronary risk factors and no-reflow phenomenon. The symptom onset to reperfusion time, TIMI flow grade before stent deployment, plaque area, soft plaques, eccentric plaques, plaque rupture and thrombosis may be risk factors for the no-reflow phenomenon after PCI. [ABSTRACT FROM AUTHOR]

A reduced basal and increased topdressing fertilizer rate (RBIT) can usually increase rice yield, but whether this practice alleviates the impact of poor weather on rice production is unknown. Thus, the effect of three integrated RBIT treatments (RBITs, including RBIT alone, RBIT in combination with straw incorporation (RBITS) or a reduced fertilizer rate (RBITR)) on rice growth and nutritional status under different weathers was investigated in a 9-year experiment. Conventional fertilization (CF) was the control. We found that daytime temperature and light (DTL) after heading were the main meteorological factors limiting rice yield increases. RBITs did not affect rice yield under High-DTL, compared with CF, but RBITS significantly increased rice yield under Low-DTL. Compared with High-DTL, the positive effect of RBIT and RBITR on the N concentration and proportion in vegetative organs under Low-DTL was higher than the K concentration in vegetative organs, but RBITS showed the opposite trend. Regression analysis indicated that the harvest index had stronger correlations with the N concentration (negative), K concentration (positive), and N/K (negative) in vegetative organs under Low-DTL than under High-DTL. Our findings suggested that RBITS could improve rice adaptability to daytime temperature and light changes after heading by balancing crop nutritional status (N/K). [ABSTRACT FROM AUTHOR]

During pesticide spraying operations, the downwash airflow generated by the rotor UAV disperses the rice canopies with different wind vortex intensities, resulting in different degrees of morphological changes of rice sheaves in the target area. However, it is inconclusive whether it will affect rice yield. In this paper, dispersed canopy parameters and rice yield data through experiments of conventional flight operation and unconventional hovering operation were collected, aiming to conduct a comparative analysis of the effects of UAV wind vortex intensity on the morphology and yield of rice sheaves in the spraying operation. The results showed that in the conventional flight operation, the wind vortex had little effect on rice morphology and yield. Due to the influence of the short downwash airflow, the rice canopies were rapidly dispersed and produced a restorable canopy-vortex patch. After the UAV withdrew, the rice canopies recovered immediately. In the unconventional hovering operation, with the increase of vortex intensity, the rice canopies forged unrestorable canopy-vortex, which caused significant changes in rice morphology and eventually led to a yield reduction, of 1.21% at preliminary heading stage, 9.05% at full heading stage and 4.87% at mature stage. The experiments indicated that wind vortex did not affect rice during conventional plant protection, while the unrestorable canopy-vortex patch caused by the prolonged operational duration in unconventional hovering operation did affect rice morphology and yield, especially after the full heading stage. [ABSTRACT FROM AUTHOR]

Poor grain-filling initiation in inferior spikelets severely impedes rice yield improvement, while photo-assimilates from source leaves can greatly stimulate the initiation of inferior grain-filling (sink). To investigate the underlying mechanism of source-sink interaction, a two-year field experiment was conducted in 2019 and 2020 using two large-panicle rice cultivars (CJ03 and W1844). The treatments included intact panicles and partial spikelet removal. These two cultivars showed no significant difference in the number of spikelets per panicle. However, after removing spikelet, W1844 showed higher promotion on 1000-grain weight and seed-setting rate than CJ03, particularly for inferior spikelets. The reason was that the better sink activity of W1844 led to a more effective initiation of inferior grain-filling compared to CJ03. The inferior grain weight of CJ03 and W1844 did not show a significant increase until 8 days poster anthesis (DPA), which follows a similar pattern to the accumulation of photo-assimilates in leaves. After removing spikelets, the source leaves of W1844 exhibited lower photosynthetic inhibition compared to CJ03, as well as stronger metabolism and transport of photo-assimilates. Although T6P levels remained constant in both cultivars under same conditions, the source leaves of W1844 showed notable downregulation of SnRK1 activity and upregulation of phytohormones (such as abscisic acid, cytokinins, and auxin) after removing spikelets. Hence, the high sink strength of inferior spikelets plays a role in triggering the enhancement of source strength in rice leaves, thereby fulfilling grain-filling initiation demands. [ABSTRACT FROM AUTHOR]

The hybrid assistive limb (HAL) provides motion assistance based on bioelectrical signals detected on the skin surface when muscle forces are generated. The lumbar-type HAL is expected to expand the therapeutic options for severe cardiac patients who have difficulty in moving on their own legs. We aim to compare the efficacy of exercise therapy performed with assistance from a lumbar-type HAL versus conventional training (sit-to-stand exercise without HAL) in patients with chronic heart failure. This investigation will be a randomized, nonblinded, controlled study. Sixty patients who satisfy the criteria to receive cardiac rehabilitation therapy under the Japanese national insurance system will be enrolled at the University of Tsukuba Hospital. Participants randomly assigned to 2 groups (HAL group and conventional group) at a 1:1 allocation ratio will perform exercise therapy either with HAL or without HAL for 5–30 min once a day for 6–10 days. Outcome parameters will be measured just before and after the completion of the exercise therapy and at 1 year after hospital discharge. The primary outcomes will be the heart rate, blood pressure, subjective ratings of exercise intensity during exercise (Borg scale), number of days from the start of exercise therapy to independent walking and to discharge, and prognosis (mortality and cardiovascular events) over the 1-year period after discharge. The secondary outcomes will be the assessment of heart failure severity, brain natriuretic peptide, grip strength, thigh muscle thickness, isometric knee extensor strength, standing ability, 10-meter walking speed, 6-min walking distance, short physical performance battery, and adverse events. Unpaired t tests will be used for baseline assessments and outcome measures. This is the first randomized controlled study to examine the efficacy and feasibility of lumbar-type HAL in patients with chronic heart failure. If the results confirm beneficial effects in the outcomes of patients with heart failure, this study will add more evidence in support of the use of the lumbar-type HAL as an effective tool in new cardiac rehabilitation programs. [ABSTRACT FROM AUTHOR]

A correction to the article "Lodging Resistance of Japonica Rice (Oryza Sativa L.): Morphological and Anatomical Traits Due to Top-Dressing Nitrogen Application Rates" in the previous issue is presented.

Rice (Oryza sativa L.) is the most widely consumed staple crop for approximately half of the world's population. Many interactions take place in paddy soil, particularly in the rice mycorrhizosphere region. Arbuscular mycorrhizal fungi (AMF) and soil microbe interactions are among the most important and influential processes that occur, as they significantly influence the plant growth and soil structure properties. Their interactions may be of crucial importance to the sustainable, low-input productivity of paddy ecosystems. In this study, we summarize the major groups of microbial communities interacting with arbuscular mycorrhizal fungi in the rice mycorrhizosphere, and discuss the mechanisms involved in these arbuscular mycorrhizal fungi and microbe interactions. We further highlight the potential application of arbuscular mycorrhizal mutualism in paddy fields, which will be helpful for the production of bioinoculants in the future. [ABSTRACT FROM AUTHOR]

In this article, the disk mill cutter path generation strategy for the machining of complex helical surface via a currently developed minimal orientation-distance algorithm based on spatial discretization method is studied. The strategy proposed here is, first, to establish the helical surface and cutting surface in the unique coordinate system. Then, the two surfaces are divided into a series of parts by n equidistant planes, and the minimal orientation-distance algorithm is used to determine all the cutter locations. Finally, on the basis of Archimedes helical interpolation, cutter path is generated within the specified tolerance limit. The effectiveness of the proposed strategy is confirmed numerically and experimentally by a case of virtual cutting test in VERICUT software and actual machining. This strategy can be applied to a broad range of helical surface machining. [ABSTRACT FROM AUTHOR]

The objective of the study was to clarify whether controlling nutritional status (CONUT) is useful for predicting the long-term prognosis of patients hospitalized with heart failure (HF). A total of 482 (57.5%) HF patients from the Ibaraki Cardiovascular Assessment Study-HF ( N = 838) were enrolled (298 men, 71.7 ± 13.6 years). At admission, blood samples were collected and nutritional status assessed using CONUT. CONUT scores were defined as follows: 0-1, normal; 2-4, light; 5-8, moderate; and 9-12, severe undernutrition. Accordingly, 352 (73%) patients had light-to-severe nutritional disturbances. In the follow-up period [median 541.5 (range 354-786) days], 109 deaths were observed. A Kaplan-Meier analysis revealed that all-cause deaths occurred more frequently in HF patients with nutritional disturbances [ n = 93 (26.4%)] than in those with normal nutrition [ n = 16 (12.3%); log-rank p < 0.001]. The Cox proportional hazard analyses revealed that a per point increase in the CONUT score was associated with an increased risk of all-cause death (hazard ratio 1.142; 95% confidence interval, 1.044-1.249) after controlling simultaneously for age, sex, previous history of HF hospitalization, log brain natriuretic peptide, and use of therapeutic agents at admission (tolvaptan and aldosterone antagonists). This study suggests that nutritional screening using CONUT scores is helpful in predicting the long-term prognosis of patients hospitalized with HF in a multicenter registry setting. [ABSTRACT FROM AUTHOR]

In the double rice cropping system, early/late season rice cultivars can be grown in both early and late seasons. However, the functional properties and starch structures of early/late-season rice between the early and late seasons are still unclear. Here, we conducted a field experiment with two typical early/late season rice cultivars. Compared to early rice, late rice had higher hardness and stickiness and lower peak viscosity, breakdown, and pasting temperature. The higher hardness, lower peak viscosity and breakdown of late rice were dominated by its higher amylose content (i.e., the proportion of amylose chains, DP 100–10000). The lower crystallinity and ratio of 1045/1022 cm−1 of late rice was due to its long and very long amylopectin branch chains (DP 25–70), resulting in a lower pasting temperature. We considered that the higher stickiness of late rice was due to a higher proportion of short and medium amylopectin branch chains (DP 6–24). Furthermore, the setback (short-term retrogradation) showed a significant difference between cultivars, which might be related to the difference in long amylopectin branch chains (DP 37–70) and their intermolecular interactions with amylose molecules. These findings are expected to provide important information for improving rice palatability and developing the rice industry of early/late season rice in the double rice cropping system. [Display omitted] • Early and late rice have different cooked rice textures and pasting properties. • The high hardness of late rice was dominated by its high amylose content. • The high stickiness of late rice depends on more short and medium branch chains. • Late rice has a less crystalline structure, resulting in a low pasting temperature. [ABSTRACT FROM AUTHOR]

Objectives: To examine the possible involvement and regulatory mechanisms of extracellular signal-regulated kinase (ERK) pathway in the temporomandibular joint (TMJ) of rats subjected to chronic sleep deprivation (CSD). Methods: Rats were subjected to CSD using the modified multiple platform method (MMPM). The serum levels of corticosterone (CORT) and adrenocorticotropic hormone (ACTH) were tested and histomorphology and ultrastructure of the TMJ were observed. The ERK and phospho-ERK (p-ERK) expression levels were detected by Western blot analysis, and the MMP-1, MMP-3, and MMP-13 expression levels were detected by real-time quantitative polymerase chain reaction (PCR) and Western blotting. Results: The elevated serum CORT and ACTH levels confirmed that the rats were under CSD stress. Hematoxylin and eosin (HE) staining and scanning electron microscopy (SEM) showed pathological alterations in the TMJ following CSD; furthermore, the p-ERK was activated and the mRNA and protein expression levels of MMP-1, MMP-3, and MMP-13 were upregulated after CSD. In the rats administered with the selective ERK inhibitor U0126, decreased tissue destruction was observed. Phospho-ERK activation was visibly blocked and the MMP-1, MMP-3, and MMP-13 mRNA and protein levels were lower than the corresponding levels in the CSD without U0126 group. Conclusion: These findings indicate that CSD activates the ERK pathway and upregulates the MMP-1, MMP-3, and MMP-13 mRNA and protein levels in the TMJ of rats. Thus, CSD induces ERK pathway activation and causes pathological alterations in the TMJ. ERK may be associated with TMJ destruction by promoting the expression of MMPs. [ABSTRACT FROM AUTHOR]

The effects of exogenous application of γ-aminobutyric acid (GABA) on yield and quality characteristics, especially 2-acetyl-1-pyrroline (2AP) biosynthesis, are rarely investigated. Two field experiments, i.e., experiment 1 (EXP.1) and experiment 2 (EXP.2), were conducted, and four GABA levels, i.e., 0, 50, 500, 1000 mg l−1, classified as CK, T1, T2, and T3, respectively, were sprayed at the initial heading stage of a fragrant rice cultivar, Yuxiangyouzhan. The results showed that exogenous GABA application increased the 2AP content in grains 8.58%–19.44% in EXP.1 and 0.01%–6.22% in EXP.2. Exogenous GABA treatments also increased the GABA concentration in the grains and proline content in fragrant rice. Significant correlations between the grain 2AP content and proline content in leaves at 5 days after spraying were also detected in EXP.1, whereas GABA application did not significantly affect leaf dry weight, total dry weight, or grain yield. Moreover, gas exchange parameters, soil-plant analyses development values, and antioxidant activities were improved under GABA treatments. Additionally, the GABA applications substantially improved the grain quality characteristics, including milled rice percentage, head rice percentage, and protein content. Overall, exogenous GABA application was effective in the improvement of quality characteristics in fragrant rice, especially that of grain 2AP contents. Exogenous application of GABA in the modulation of 2AP in fragrant rice. Pro: proline; OAT: ornithine aminotransferase; Orn: ornithine; Put: putrescine; PDH: proline dehydrogenase; GABald: γ-aminobutyraldehyde; 2AP: 2-acetyl-1-pyrroline; P5C: Δ1-pyrroline-5-carboxylate; P5CS: Δ1-pyrroline-5-carboxylate synthetase; Glu: glutamic acid; GAD: glutamate decarboxylase; GABA: γ-aminobutyric acid; MG: methylglyoxal. Image 1 • Exogenous GABA application induced 2AP accumulation in fragrant rice. • Exogenous GABA application regulated plant growth and grain quality. • The 2AP content in grains was highly associated with GABA concentration in grains. [ABSTRACT FROM AUTHOR]

Introduction: The Hybrid Assistive Limb (HAL) is the world's first cyborg-type robot that improves, supports and expands wearer's physical functions, by detecting bioelectrical signals on skin surface above muscles when a wearer tries to generate the muscle forces. Lumbar-type HAL is expected to expand the possibilities of exercise therapy for severe cardiac patients who have difficulty in moving on their own legs. Before applying this device to cardiac patients, we examined whether the motion assistance by HAL could effectively reduce the cardiopulmonary burden during squat exercise, i.e., one of the usual cardiac rehabilitation programs, in healthy subjects. Methods: A total of 12 healthy subjects (33 ± 11 years) underwent squat exercise of 20 times per minute for 3 minutes with and without a lumbar-type HAL, during which respiratory gas analyses were performed. The oxygen uptake (VO2), carbon dioxide output (VCO2), minute ventilation (VE), and the Borg Scale were monitored during exercise. Results: All subjects completed squat exercise for 3 minutes both with and without HAL. VO2 (927 ± 205 vs 976 ± 176 mL/min, p<0.05) and the Borg Scale (12.7 ± 1.1 vs 13.7 ± 0.7, p<0.05) at the end of exercise were significantly lower when HAL was used. When 2 subjects who regularly perform high-intensity exercise for more than 10 hours per week were excluded from analyses, VO2 (868 ± 165 vs 953 ± 157 mL/min, p<0.01), VCO2 (770 ± 189 vs 847 ± 194 mL/min, p<0.05), VE (24.0 ± 5.8 vs 26.0 ± 5.6 L/min, p<0.05) and the Borg Scale (12.9 ± 1.1 vs 13.8 ± 0.7, p<0.05) were significantly lower when HAL was used. Conclusions: Our results demonstrate that the lumbar-type HAL significantly reduces cardiopulmonary burden during squat exercise in healthy subjects. The effects were striking especially in sedentary subjects. Further studies on cardiac patients are expected to establish a new cardiac rehabilitation program using HAL. [ABSTRACT FROM AUTHOR]