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The development of polyaniline (PANI)/biomaterial composites as humidity sensor materials represents an emerging area of advanced materials with promising applications. The increasing attention to biopolymer materials as desiccants for humidity sensor components can be explained by their sustainability and propensity to absorb water. This review represents a literature survey, covering the last decade, which is focused on the interrelationship between the core properties and moisture responsiveness of multicomponent polymer/biomaterial composites. This contribution provides an overview of humidity-sensing materials and the corresponding sensors that emphasize the resistive (impedance) type of PANI devices. The key physicochemical properties that affect moisture sensitivity include the following: swelling, water vapor adsorption capacity, porosity, electrical conductivity, and enthalpies of adsorption and vaporization. Some key features of humidity-sensing materials involve the response time, recovery time, and hysteresis error. This work presents a discussion on various types of humidity-responsive composite materials that contain PANI and biopolymers, such as cellulose, chitosan and structurally related systems, along with a brief overview of carbonaceous and ceramic materials. The effect of additive components, such as polyvinyl alcohol (PVA), for film fabrication and their adsorption properties are also discussed. The mechanisms of hydration and proton transfer, as well as the relationship with conductivity is discussed. The literature survey on hydration reveals that the textural properties (surface area and pore structure) of a material, along with the hydrophile–lipophile balance (HLB) play a crucial role. The role of HLB is important in PANI/biopolymer materials for understanding hydration phenomena and hydrophobic effects. Fundamental aspects of hydration studies that are relevant to humidity sensor materials are reviewed. The experimental design of humidity sensor materials is described, and their relevant physicochemical characterization methods are covered, along with some perspectives on future directions in research on PANI-based humidity sensors.

Climatic extremes have adverse concurrent and lagged effects on terrestrial carbon cycles. Here, a concurrent effect refers to the occurrence of a latent impact during climate extremes, and a lagged effect appears sometime thereafter. Nevertheless, the uncertainties of these extreme drought effects on net carbon uptake and the recovery processes of vegetation in different Tibetan Plateau (TP) ecosystems are poorly understood. In this study, we calculated the Standardised Precipitation–Evapotranspiration Index (SPEI) based on meteorological datasets with an improved spatial resolution, and we adopted the Carnegie–Ames–Stanford approach model to develop a net primary production (NPP) dataset based on multiple datasets across the TP during 1982–2015. On this basis, we quantised the net reduction in vegetation carbon uptake (NRVCU) on the TP, investigated the spatiotemporal variability of the NPP, NRVCU and SPEI, and analysed the NRVCUs that are caused by the concurrent and lagged effects of extreme drought and the recovery times in different ecosystems. According to our results, the Qaidam Basin and most forest regions possessed a significant trend towards drought during 1982–2015 (with Slope of SPEI < 0, P < 0.05), and the highest frequency of extreme drought events was principally distributed in the Qaidam Basin, with three to six events. The annual total net reduction in vegetation carbon uptake on the TP experienced a significant downward trend from 1982 to 2015 (−0.0018 ± 0.0002 PgC year−1, P < 0.001), which was negatively correlated with annual total precipitation and annual mean temperature (P < 0.05). In spatial scale, the NRVCU decrement was widely spread (approximately 55% of grids) with 17.86% of the area displaying significant declining trends (P < 0.05), and the sharpest declining trend (Slope ≤ −2) was mainly concentrated in southeastern TP. For the alpine steppe and alpine meadow ecosystems, the concurrent and lagged effects of extreme drought induced a significant difference in NRVCU (P < 0.05), while forests presented the opposite results. The recovery time comparisons from extreme drought suggest that forests require more time (27.62% of grids ≥ 6 years) to recover their net carbon uptakes compared to grasslands. Therefore, our results emphasise that extreme drought events have stronger lagged effects on forests than on grasslands on the TP. The improved resilience of forests in coping with extreme drought should also be considered in future research.

The ongoing miniaturization and cost reduction of electronic devices (microprocessors, sensors, batteries, and wireless communication units) have allowed the proliferation of the Internet of Things (IoT)-based applications. Many of these applications are mission-critical (e.g., healthcare and traffic road management), in the sense that the IoT system needs to take critical decisions in real-time. Hence, these IoT systems need to be designed using effective fault-tolerant techniques like disaster recovery (DR) solutions. This work proposes a Petri net-based approach for modeling and analysis of DR solutions for IoT infrastructures. The proposed models allow assessing important DR measures, such as system availability, cost, and recovery time objective. To demonstrate the feasibility of our approach, we present a case study in which a real-world healthcare IoT system is modeled and analyzed. Besides, sensitivity analysis is carried out to assess the effects of model parameters on the system availability.

Among other approaches, camera trap distance sampling (CTDS) is used to estimate animal abundance from unmarked populations. It was formulated for videos and observation distances are measured at predetermined ‘snapshot moments’. Surveys recording still images with passive infrared motion sensors suffer from frequent periods where animals are not photographed, either because of technical delays before the camera can be triggered again (i.e. ‘camera recovery time’) or because they remain stationary and do not immediately retrigger the camera following camera recovery time (i.e. ‘retrigger delays’). These effects need to be considered when calculating temporal survey effort to avoid downwardly biased abundance estimates. Here, we extend the CTDS model for passive infrared motion sensor recording of single images or short photo series. We propose estimating ‘mean time intervals between triggers’ as combined mean camera recovery time and mean retrigger delays from the time interval distribution of pairs of consecutive pictures, using a Gamma and Exponential function, respectively. We apply the approach to survey data on red deer, roe deer and wild boar. Mean time intervals between triggers were very similar when estimated empirically and when derived from the model‐based approach. Depending on truncation times (i.e. the time interval between consecutive pictures beyond which data are discarded) and species, we estimated mean time intervals between retriggers between 8.28 and 15.05 s. Using a predefined snapshot interval, not accounting for these intervals, would lead to underestimated density by up to 96% due to overestimated temporal survey effort. The proposed approach is applicable to any taxa surveyed with camera traps. As programming of cameras to record still images is often preferred over video recording due to reduced consumption of energy and memory, we expect this approach to find broad application, also for other camera trap methods than CTDS.

Drought, a recurring climatic challenge characterized by water scarcity, significantly affects the growth and functional stability of terrestrial vegetation. This study closely examines how extreme droughts vary and how the vegetation recovery period changes on the basis of multi‐source meteorological and remote satellite data. It also assesses the impacts of specific drought characteristics on vegetation recovery time in Guizhou Province, China. The results indicate that drought events are predominantly observed in the summer and autumn seasons across most of Guizhou Province, with a notable cessation of these dry spells often occurring in September and October. The northern and southwestern regions of Guizhou Province tend to experience the onset of drought conditions at an earlier date than other regions, with a concomitant trend of earlier termination of drought events in the northern locales. Droughts typically last 3–5 months, with mild and moderate droughts being the most common. The spatial distribution of vegetation recovery period from the droughts follows a discernible pattern, with most areas recovering within 2 months after drought ceases, whereas the Guiyang, Zunyi, Qiannan, and Qiandongnan regions need 4 to 6 months to recover in some years. Furthermore, substantial variations in vegetation recovery patterns have been observed among diverse land cover types. The average recovery period of forests ranged from 1.60 to 2.98 months, that of shrublands from 1.76 to 3.21 months, whereas the vegetation in croplands showed a relatively shorter recovery period, with most areas returning to normal levels within approximately 1 month. The recovery characteristics of vegetation were jointly influenced by the features of drought. Drought duration and severity often prolonged the length of the recovery period. This study provides a scientific basis for the formulation of regional drought management and ecological conservation strategies. Assessing characteristics of drought over the last 20 years in Guizhou Province, China. Unraveling the dynamics of vegetation recovery period across various land cover types. Drought duration and severity determine vegetation recovery period.

Background Multidrug-resistant tuberculosis (MDR-TB) is caused by bacteria that are resistant to the most effective anti-tuberculosis drug. The MDR-TB is an increasing global problem and the spread of MDR-TB has different recovery time for different patients. Therefore, this study aimed to investigate the recovery time of MDR-TB patients in Amhara region, Ethiopia. Method A retrospective study was carried out in seven hospitals having MDR-TB treatment center of Amhara region, Ethiopia from September 2015 to February 2018. An accelerated failure time and parametric shared frailty models were employed. Results The study revealed that the recovery time of MDR-TB patients in Amhara region was 21 months. Out of the total MDR-TB patients, 110 (35.4%) censored and 201 (64.6%) cured of MDR-TB. The clustering effect of frailty model was hospitals and the Weibull-gamma shared frailty model was selected among all and hence used for this study. The study showed that extra pulmonary MDR-TB patients had longer recovery time than that of seamier pulmonary MDR-TB patients in Amhara region, Ethiopia. According to this study, male MDR-TB patients, MDR-TB patients with co-morbidity and clinical complication were experiencing longer recovery time than that of the counter groups. This study also showed that MDR-TB patients with poor adherence had longer recovery time than those with good adherence MDR-TB patients. Conclusion Among different factors considered in this study, MDR-TB type, clinical complication, adherence, co-morbidities, sex, and smoking status had a significant effect on recovery time of MDR-TB patients in Amhara region, Ethiopia. In conclusion, the Regional and Federal Government of Ethiopia should take immediate steps to address causes of recovery time of MDR-TB patients in Amhara region through encouraging adherence, early case detection, and proper handling of drug-susceptibility according to WHO guidelines.

Modulating the electron transport dynamics in gas sensors is crucial for achieving rapid‐response gas detection. However, polaron localization causes sluggish electron migration from the bulk to the surface, severely limiting surface electron concentration and reaction activity. In this work, we leverage the difference in migration barriers of surface Vo in CeO2 to drive the directional migration of surface Vo into the bulk via precisely controlled thermal treatment, thereby forming electron transfer channels bridging the bulk and the surface. Experiment result confirm that the formation of electron channels enhances electron transfer efficiency from bulk to surface, leading to a dual improvement in both electron concentration and reaction activity at surface Vo sites, which further promotes the adsorption and activation of O2 and NO2. Enabled by this strategy, CeO2 achieves long‐term stability and new benchmark for ultra‐fast detection of 20 ppb NO2 in 5 s at room temperature. This work provides a new strategy to resolve the kinetic contradiction between bulk electron transport and surface reactions. The formation of electron transport channels overcomes the sluggish electron migration caused by polaron localization, significantly enhancing surface electron concentration and reaction activity, thereby promoting the adsorption and activation of O2 and NO2. Enabled by this strategy, the CeO2‐based sensor achieves ultra‐fast detection of 20 ppb NO2 within 5 s at room temperature.

To address the beam loading issue in a linear accelerator, a composite control strategy combining PI feedback and ILC feedforward based on klystron and cavity modeling is proposed. Simulations show that 50 iterations reduce the cavity voltage undershoot from 8.25% to 3.25% (a 60.6% improvement) and the recovery time from 5.0 μs to 1.5 μs (a 70.0% improvement), thereby enhancing stability.

Drought imposes severe, long-term effects on global environments and ecosystems. A better understanding of how long it takes a region to recover to pre-drought conditions after drought is essential for addressing future ecology risks. In this study, drought-related variables were obtained using remote sensing and reanalysis products for 2003 to 2016. The meteorological drought index [standardized precipitation evapotranspiration index (SPEI)] and agricultural drought index [vegetation condition index (VCI)] were employed to estimate drought duration time (DDT) and drought recovery time (DRT). To the basin’s west, decreasing rainfall and increasing potential evapotranspiration led to decreasing SPEI. On the east side, decreasing soil moisture from each depth effects vegetation condition, which results in a decreasing gross primary productivity and VCI. Extreme meteorological drought events are likely to occur in the basin’s northeastern and middle western areas, while the southern basin is more likely to suffer from extreme agricultural drought events. The mean SPEI-based DDT (2.45 months) was smaller than the VCI-based DDT (2.97 months); the average SPEI-based DRT (2.02 months) was larger than the VCI-based DRT (1.63 months). Most of the area needs 1 or 2 months to recover from drought except for the basin’s northwestern area, where the DRT is more than 8 months. DDT is the most important parameter in determining DRT. These results provide useful information about regional drought recovery that will help local governments looking to mitigate potential environmental risks and formulate appropriate agricultural policies in Lake Victoria Basin.

Background Increased intracranial pressure (ICP) in patients with hypertensive intracerebral hemorrhage (HICH) has been associated with poor prognosis. The transsylvian insular approach (TIA) and the transcortical (TCA) approach are applied for patients with HICH. We aimed to compare the postoperative ICP parameters of TIA and TCA to identify which procedure yields better short-term outcomes in patients with basal ganglia hematoma volumes ranging from 30 to 50 mL. Methods Eighty patients with basal ganglia hematomas 30–50 mL were enrolled in this study. Patients were implanted with ICP probes and divided into TIA and TCA groups according to the procedure. The ICP values were continuously recorded for five days at four-hour intervals. Short-term outcomes were evaluated using the length of hospitalization and postoperative consciousness recovery time. Results No statistically significant differences were found in age, sex, GCS score at admission, hematoma volume, and hematoma clearance rate (p > 0.05). The results showed that postoperative initial ICP, ICP on the first postoperative day, mean ICP, DICP20 mmHg × 4 h, postoperative consciousness recovery time, the length of hospitalization, mannitol utilization rate and the mannitol dosage were lower in the TIA group than in the TCA group (p < 0.05). Postoperative consciousness recovery time was positively correlated with ICP on the first postoperative day, and the length of hospitalization was positively correlated with mean ICP. Conclusions TIA is more effective than TCA in improving the short-term outcomes of patients with basal ganglia hematoma volumes ranging from 30 to 50 mL according to comparisons of postoperative ICP parameters.