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Reactive oxygen species (ROS) are well known for their dual functions in plants. On the one hand, ROS were once thought to be harmful to plants because their excessive accumulation might lead to oxidative stress and cause cell injury in severe cases. On the other hand, a timely and appropriate burst of ROS acts as an important signal for plant growth, development and defence against environmental stress. ROS are common molecules in various plant metabolic processes and can be generated almost anywhere in plant cells. NADPH oxidase located on the plasma membrane, also known as the RBOH protein, provides a very important ROS synthesis pathway. This article briefly summarizes the signal functions of ROS, especially RBOH-dependent ROS, in plant growth, development and defence against abiotic and biotic stress in Arabidopsis (Arabidopsis thaliana).

BACKGROUND: Jasmonates are ubiquitously occurring lipid-derived compounds with signal functions in plant responses to abiotic and biotic stresses, as well as in plant growth and development. Jasmonic acid and its various metabolites are members of the oxylipin family. Many of them alter gene expression positively or negatively in a regulatory network with synergistic and antagonistic effects in relation to other plant hormones such as salicylate, auxin, ethylene and abscisic acid. SCOPE: This review summarizes biosynthesis and signal transduction of jasmonates with emphasis on new findings in relation to enzymes, their crystal structure, new compounds detected in the oxylipin and jasmonate families, and newly found functions. CONCLUSIONS: Crystal structure of enzymes in jasmonate biosynthesis, increasing number of jasmonate metabolites and newly identified components of the jasmonate signal-transduction pathway, including specifically acting transcription factors, have led to new insights into jasmonate action, but its receptor(s) is/are still missing, in contrast to all other plant hormones.

Background Access to safe abortion is legally restricted in Liberia, forcing women to resolve unintended pregnancies through unsafe methods, leading to severe illnesses and deaths. Liberia’s Government has committed to addressing abortion-related maternal mortalities by availing comprehensive post-abortion care. However, limited information exists on the capacity of health facilities to provide quality abortion-related care. This paper assesses the extent to which health facilities in Liberia are capable of delivering safe abortion and post-abortion care services. Methods Data for this analysis are drawn from a signal function survey conducted across 48 public facilities in Liberia from September to November 2021. The signal function survey captures several safe abortion and post-abortion care-related services, including staff training, equipment, commodities, and supplies. Data were collected from health providers knowledgeable about abortion-related care, such as safe abortion and post-abortion care, across sampled health facilities using a structured questionnaire. Data analysis involved summarizing proportions of clinics, health centers, and hospitals with the capacity to provide either basic and/or comprehensive safe abortion and post-abortion care. Results Out of the 48 facilities, 65% and 28% were classified as capable of providing basic and comprehensive post-abortion care (PAC) services, respectively. Fewer facilities (27%) could provide basic safe abortion care (SAC) and comprehensive SAC (16%). Differences by facility level were statistically significant for comprehensive PAC. The PAC signal functions fulfilled by the fewest facilities included referral capacity, blood transfusion, and surgical or laparotomy capacity. Conclusion The study highlights the limitations to providing basic SAC and PAC among our sample of public health facilities in Liberia and the poor capacity of these health facilities to provide comprehensive PAC and SAC services in particular. Full implementation of the 2019 National Comprehensive Abortion Care Guidelines could strengthen critical SAC and PAC services by ensuring adequate resources and training of the healthcare workforce.

Many animal taxa perform stereotyped displays during ritualized contests over territory and mates. Such displays facilitate assessment of an opponent's prowess and reduce the probability of physical injury. Color patterns likewise can serve as indicators of an individual's body condition. Male San Cristóbal Lava Lizards (Microlophus bivittatus) of the Galápagos Islands possess a black epaulet on each shoulder that contrasts with their surrounding body coloration. We created robots with the appearance of conspecific males to explore the potential function(s) of the epaulets in a series of four experiments. Our experiments focused on epaulet presence/absence, body location, and location relative to the axis of body motion (pectoral versus pelvic girdle) during pushups. Paired trials were conducted with adult males and females using a robot that performed M. bivittatus signature displays and that differed on its two sides in epaulet attributes. We quantified two kinds of bobbing displays in subjects: signature displays and two-bob displays. We also computed a composite response (CR) score, in which point values were assigned to types of nonbobbing displays and display combinations according to the apparent level of subject aggression. Results of Experiment 1 showed that males (but not females) performed more signature displays to the side of the robot with the epaulet present than to the side with the epaulet absent, suggesting that epaulets serve a signaling function. Composite response scores did not differ between treatments for either sex. In Experiment 2 neither males nor females performed more bobbing displays to an enlarged epaulet than to an epaulet reduced in size. However, males exhibited greater CR scores to the enlarged epaulet, suggesting that epaulet size or conspicuousness is important to its function. In Experiment 3 neither sex produced more bobbing displays to an epaulet on the robot's shoulder than to one on its hip. Yet, males accumulated significantly larger CR scores in response to the shoulder epaulet than to the hip epaulet, indicating that males were aware of normal epaulet location. Finally, in Experiment 4, where our robot performed hindlimb rather than forelimb pushups, subjects failed to exhibit more bobbing displays in response to a shoulder epaulet than to a hip epaulet. CR scores also did not differ between treatments for either sex, perhaps due to the striking abnormality of hindlimb-driven bobbing displays. Although the function of M. bivittatus epaulets remains elusive, these markings clearly are salient to male conspecifics.

We consider a nonlinear function-on-function additive regression model with multiple functional predictors. The forms of the nonlinear functions are unspecified, and offer great flexibility to model various relationships between the response curve and predictor curves. We clarify the identifiability issue of the model and identify the best decompositions of the nonlinear functions in the model in terms of prediction. To estimate this expansion, we solve a penalized functional generalized eigenvalue problem followed by a penalized least squares procedure. With the minimum prediction error of the proposed decomposition, our approach has good prediction accuracy. Our approach converts the estimation of three-dimensional nonlinear functions to the estimation of two- and one-dimensional functions, which considerably reduces computational costs. Asymptotic results are provided, and simulations and a data application show that the proposed method has good predictive performance and is efficient in dimension reduction and computation. This method is implemented in the R package FRegSigCom.

Although conflict is often adaptive and necessary to secure limited resources, it is also frequently a costly endeavor. Signals that reliably communicate competitive ability are commonly employed by animals to reduce conflict costs. Both male and female signals have the capacity to serve as honest indicators of competitive ability, but the extent to which this occurs in females has received relatively limited attention. We studied how natural feather coloration and experimentally manipulated plumage ornamentation in female white-shouldered fairywrens (Malurus alboscapulatus moretoni) relates to their aggressive behavior. These fairywrens are a useful study system in that female, but not male coloration varies throughout New Guinea. We tested behavioral responses to simulated rivals both prior to and after plumage manipulation via two distinct behavioral assays: simulated territorial intrusions (where both sexes jointly respond to rival intruders) and mirror image simulation (where females are isolated from their mate). Plumage manipulation treatments had no measurable impact on female aggression during mirror image simulation tests, though aggression did decrease over the course of multiple assays. Similarly, using simulated territorial intrusion assays, we found no difference in female aggression with respect to both natural coloration and manipulation treatment. Finally, our correlative analysis of natural feather color also revealed no detectable relationship. These findings suggest that female white scapular coloration is unlikely to function as a signal of competitive ability in this tropical species with derived female ornamentation and we discuss possible alternative explanations.

In this study, the effects of electrode porosity on nerve regeneration and functional recovery after sciatic nerve transection in rats was investigated. A sieve-type neural electrode with 70% porosity was designed and compared with an electrode with 30% porosity. Electrodes were fabricated from photosensitive polyimide and implanted into the transected sciatic nerves. Motor function recovery was evaluated using the Sciatic Function Index. The number of active channels and their signal quality were recorded and analyzed to assess the sensory neural signal acquisition. Electrical impedance spectroscopy was used to evaluate the electrode performance. The group implanted with the 70% porosity electrode demonstrated significantly enhanced nerve regeneration and motor function recovery, approaching control group levels by the fifth week. In contrast, the group with the 30% porosity electrode exhibited limited improvement. Immunohistochemical analysis confirmed extensive nerve fiber growth within the 70% porous structure. Moreover, the 70% porosity electrode consistently acquired neural signals from more channels compared to the 30% porosity electrode, demonstrating its superior performance in sensory signal detection. These findings emphasize the importance of optimizing electrode porosity in the development of advanced neural interfaces, with the potential to enhance clinical outcomes in peripheral nerve repair and neuroprosthetic applications.

With the deepening of economic and financial globalization and integration, the possibility of financial crisis in a country or a region has obviously increased. Therefore, it is particularly important to prevent and resolve the financial crisis, especially the regional financial crisis. Therefore, this paper studies the application of sine signal function in financial crisis early warning and detection system. According to the principle of “different frequencies are uncorrelated,” the derivation process of a single sinusoidal signal with noise in the crisis warning period is also applicable to the case of multiple sinusoidal signals, so the program can also be used to detect multiple sinusoidal signals in the crisis warning period at the same time. The research shows that the approximate frequency of the frequency to be measured is estimated before measurement, the initial driving force frequency is set in the range of 1–2 times of the estimated value, and the program is executed to search the extreme value of the variance of the output. The frequency value of the driving force corresponding to the extreme value of variance is the frequency value of the signal to be measured, and the simulation results show that the accuracy is about 2%. Therefore, through the application of sine signal function in the financial crisis early warning and detection system, it can provide forward‐looking suggestions for the economic policymakers of various countries, so as to take effective preventive measures in advance for the possible international financial crisis in the future. While the prediction accuracy is not absolute, the findings provide meaningful insights.

Background Abortion-related complications contribute to preventable maternal mortality, accounting for 9.8% of maternal deaths globally, and 15.6% in sub-Saharan Africa. High-quality postabortion care (PAC) can mitigate the negative health outcomes associated with unsafe abortion. While the expanded Global Gag Rule policy did not prohibit the provision of PAC, other research has suggested that over-implementation of the policy has resulted in impacts on these services. The purpose of this study was to assess health facilities’ capacity to provide PAC services in Uganda and PAC and safe abortion care (SAC) in Ethiopia during the time in which the policy was in effect. Methods We collected abortion care data between 2018 and 2020 from public health facilities in Ethiopia ( N  = 282) and Uganda ( N  = 223). We adapted a signal functions approach to create composite indicators of health facilities’ capacity to provide basic and comprehensive PAC and SAC and present descriptive statistics documenting the state of service provision both before and after the GGR went into effect. We also investigate trends in caseloads over the time-period. Results In both countries, service coverage was high and improved over time, but facilities’ capacity to provide basic PAC services was low in Uganda (17.8% in 2019) and Ethiopia (15.0% in 2020). The number of PAC cases increased by 15.5% over time in Uganda and decreased by 7% in Ethiopia. Basic SAC capacity increased substantially in Ethiopia from 66.7 to 82.8% overall, due in part to an increase in the provision of medication abortion, and the number of safe abortions increased in Ethiopia by 9.7%. Conclusions The findings from this analysis suggest that public health systems in both Ethiopia and Uganda were able to maintain essential PAC/SAC services during the GGR period. In Ethiopia, there were improvements in the availability of safe abortion services and an overall improvement in the safety of abortion during this time-period. Despite loss of partnerships and potential disruptions in referral chains, lower-level facilities were able to expand their capacity to provide PAC services. However, PAC caseloads increased in Uganda which could indicate that, as hypothesized, abortion became more stigmatized, less accessible and less safe.

Background The provision of quality obstetric care in health facilities is central to reducing maternal mortality, but simply increasing childbirth in facilities not enough, with evidence that many facilities in sub-Saharan Africa do not fulfil even basic requirements for safe childbirth care. There is ongoing debate on whether to recommend a policy of birth in hospitals, where staffing and capacity may be better, over lower level facilities, which are closer to women’s homes and more accessible. Little is known about the quality of childbirth care in Liberia, where facility births have increased in recent decades, but maternal mortality remains among the highest in the world. We will analyse quality in terms of readiness for emergency care and referral, staffing, and volume of births. Methods We assessed the readiness of the Liberian health system to provide safe care during childbirth use using three data sources: Demographic and Health Surveys (DHS), Service Availability and Readiness Assessments (SARA), and the Health Management Information System (HMIS). We estimated trends in the percentage of births by location and population caesarean-section coverage from 3 DHS surveys (2007, 2013 and 2019–20). We examined readiness for safe childbirth care among all Liberian health facilities by analysing reported emergency obstetric and neonatal care signal functions (EmONC) and staffing from SARA 2018, and linking with volume of births reported in HMIS 2019. Results The percentage of births in facilities increased from 37 to 80% between 2004 and 2017, while the caesarean section rate increased from 3.3 to 5.0%. 18% of facilities could carry out basic EmONC signal functions, and 8% could provide blood transfusion and caesarean section. Overall, 63% of facility births were in places without full basic emergency readiness. 60% of facilities could not make emergency referrals, and 54% had fewer than one birth every two days. Conclusions The increase in proportions of facility births over time occurred because women gave birth in lower-level facilities. However, most facilities are very low volume, and cannot provide safe EmONC, even at the basic level. This presents the health system with a serious challenge for assuring safe, good-quality childbirth services.