Investigating the Impact of Irrigation on Malaria Vector Larval Habitats and Transmission Using a Hydrology-Based Model.

A combination of accelerated population growth and severe droughts has created pressure on food security and driven the development of irrigation schemes across sub-Saharan Africa. Irrigation has been associated with increased malaria risk, but risk prediction remains difficult due to the heterogeneity of irrigation and the environment. While investigating transmission dynamics is helpful, malaria models cannot be applied directly in irrigated regions as they typically rely only on rainfall as a source of water to quantify larval habitats. By coupling a hydrologic model with an agent-based malaria model for a sugarcane plantation site in Arjo, Ethiopia, we demonstrated how incorporating hydrologic processes to estimate larval habitats can affect malaria transmission. Using the coupled model, we then examined the impact of an existing irrigation scheme on malaria transmission dynamics. The inclusion of hydrologic processes increased the variability of larval habitat area by around two-fold and resulted in reduction in malaria transmission by 60%. In addition, irrigation increased all habitat types in the dry season by up to 7.4 times. It converted temporary and semi-permanent habitats to permanent habitats during the rainy season, which grew by about 24%. Consequently, malaria transmission was sustained all-year round and intensified during the main transmission season, with the peak shifted forward by around 1 month. Lastly, we evaluated the spatiotemporal distribution of adult vectors under the effect of irrigation by resolving habitat heterogeneity. These findings could help larval source management by identifying transmission hotspots and prioritizing resources for malaria elimination planning.

Topographic hydro-conditioning to resolve surface depression storage and ponding in a fully distributed hydrologic model.

Land surface depressions play a central role in the transformation of rainfall to ponding, infiltration and runoff, yet digital elevation models (DEMs) used by spatially distributed hydrologic models that resolve land surface processes rarely capture land surface depressions at spatial scales relevant to this transformation. Methods to generate DEMs through processing of remote sensing data, such as optical and light detection and ranging (LiDAR) have favored surfaces without depressions to avoid adverse slopes that are problematic for many hydrologic routing methods. Here we present a new topographic conditioning workflow, Depression-Preserved DEM Processing (D2P) algorithm, which is designed to preserve physically meaningful surface depressions for depression-integrated and efficient hydrologic modeling. D2P includes several features: (1) an adaptive screening interval for delineation of depressions, (2) the ability to filter out anthropogenic land surface features (e.g., bridges), (3) the ability to blend river smoothing (e.g., a general downslope profile) and depression resolving functionality. From a case study in the Goodwin Creek Experimental Watershed, D2P successfully resolved 86% of the ponds at a DEM resolution of 10 m. Topographic conditioning was achieved with minimum impact as D2P reduced the number of modified cells from the original DEM by 51% compared to a conventional algorithm. Furthermore, hydrologic simulation using a D2P processed DEM resulted in a more robust characterization on surface water dynamics based on higher surface water storage as well as an attenuated and delayed peak streamflow.

Impact of Environmental Modifications on the Ecology, Epidemiology, and Pathogenesis of Plasmodium falciparum and Plasmodium vivax Malaria in East Africa.

Food insecurity, recurrent famine, and poverty threaten the health of millions of African residents. Construction of dams and rural irrigation schemes is key to solving these problems. The sub-Saharan Africa International Center of Excellence for Malaria Research addresses major knowledge gaps and challenges in Plasmodium falciparum and Plasmodium vivax malaria control and elimination in malaria-endemic areas of Kenya and Ethiopia where major investments in water resource development are taking place. This article highlights progress of the International Center of Excellence for Malaria Research in malaria vector ecology and behavior, epidemiology, and pathogenesis since its inception in 2017. Studies conducted in four field sites in Kenya and Ethiopia show that dams and irrigation increased the abundance, stability, and productivity of larval habitats, resulting in increased malaria transmission and a greater disease burden. These field studies, together with hydrological and malaria transmission modeling, enhance the ability to predict the impact of water resource development projects on vector larval ecology and malaria risks, thereby facilitating the development of optimal water and environmental management practices in the context of malaria control efforts. Intersectoral collaborations and community engagement are crucial to develop and implement cost-effective malaria control strategies that meet food security needs while controlling malaria burden in local communities.

Predicting distribution of malaria vector larval habitats in Ethiopia by integrating distributed hydrologic modeling with remotely sensed data.

Larval source management has gained renewed interest as a malaria control strategy in Africa but the widespread and transient nature of larval breeding sites poses a challenge to its implementation. To address this problem, we propose combining an integrated high resolution (50 m) distributed hydrological model and remotely sensed data to simulate potential malaria vector aquatic habitats. The novelty of our approach lies in its consideration of irrigation practices and its ability to resolve complex ponding processes that contribute to potential larval habitats. The simulation was performed for the year of 2018 using ParFlow-Common Land Model (CLM) in a sugarcane plantation in the Oromia region, Ethiopia to examine the effects of rainfall and irrigation. The model was calibrated using field observations of larval habitats to successfully predict ponding at all surveyed locations from the validation dataset. Results show that without irrigation, at least half of the area inside the farms had a 40% probability of potential larval habitat occurrence. With irrigation, the probability increased to 56%. Irrigation dampened the seasonality of the potential larval habitats such that the peak larval habitat occurrence window during the rainy season was extended into the dry season. Furthermore, the stability of the habitats was prolonged, with a significant shift from semi-permanent to permanent habitats. Our study provides a hydrological perspective on the impact of environmental modification on malaria vector ecology, which can potentially inform malaria control strategies through better water management.

Perioperative Nursing of Diffuse Pulmonary Ossification.

This study aims to describe the clinical manifestations of diffuse pulmonary ossification, explore the diagnostic methods to reduce the misdiagnosis rate, and discuss its nursing treatment in the perioperative period. In The Fifth Central Hospital of Tianjin, one patient with diffuse pulmonary ossification, confirmed by surgical lung biopsy, was reported; and the clinical features and effective nursing methods are analysed. The patient was a 16-year teenager, who developed sudden convulsions without obvious cause with limited respiration. After the mental state was restored, the patient presented with chest tightness, shortness of breath, cough and expectoration. Hence, the subject was admitted in our hospital. Routine and imaging examinations failed to draw a definite diagnosis. Then, lung biopsy was performed, and a diagnosis of diffuse pulmonary ossification was made. Diffuse pulmonary ossification is very rare in clinical practice. The clinical manifestations are nonspecific, and imaging features are characterised by diffuse lung damages. Therefore, it is easily misdiagnosed as other interstitial lung diseases. Lung biopsy can be used to confirm this disease. Sequential acupoint stimulation by tapping the back can relieve cough and help patients recover quickly.

Protective Effects of Ligustroflavone, an Active Compound from Ligustrum lucidum, on Diabetes-Induced Osteoporosis in Mice: A Potential Candidate as Calcium-Sensing Receptor Antagonist.

Ligustroflavone is one major compound contained in active fraction from Fructus Ligustri Lucidi (the fruit of Ligustrum lucidum), which could regulate parathyroid hormone (PTH) levels and improve calcium balance by acting on calcium-sensing receptors (CaSR). This study aimed to explore the potency of ligustroflavone as a CaSR antagonist and its protective effects against diabetic osteoporosis in mice. LF interacted well with the allosteric site of CaSR shown by molecular docking analysis, increased PTH release of primary parathyroid gland cells and suppressed extracellular calcium influx in HEK-293 cells. The serum level of PTH attained peak value at 2 h and maintained high during the period of 1 h and 3 h than that before treatment in mice after a single dose of LF. Treatment of diabetic mice with LF inhibited the decrease in calcium level of serum and bone and the enhancement in urinary calcium excretion as well as elevated circulating PTH levels. Trabecular bone mineral density and micro-architecture were markedly improved in diabetic mice upon to LF treatment for 8 weeks. LF reduced CaSR mRNA and protein expression in the kidneys of diabetic mice. Taken together, ligustroflavone could transiently increase PTH level and regulate calcium metabolism as well as prevent osteoporosis in diabetic mice, suggesting that ligustroflavone might be an effective antagonist on CaSR.

A randomized study on the effect of sequential acupoint stimulation on pulmonary function of patients with spontaneous pneumothorax during VATS perioperative period.

This study aims to explore the effect of sequential acupoint stimulation on the postoperative pulmonary function of patients with spontaneous pneumothorax who underwent video-assisted thoracoscopic surgery (VATS).Using a random number table, the patients were randomly divided into 2 groups: routine nursing group and sequential acupoint stimulation group. Patients in the routine nursing group received standard nursing care of thoracic surgery, while patients in the acupoint group received sequential acupoint stimulation on Shenshu (BL23), Gaohuang (BL43), Feishu (BL13), and Tiantu (CV22). Then, the maximal ventilatory volume (MVV), oxygen saturation (SpO2), postoperative drainage volume, postoperative drainage time, postoperative hospitalization days, and procalcitonin (PCT) were observed on the first, third, fifth and 30th day after VATS operation.On the fifth day after spontaneous pneumothorax was treated with VATS, MVV, and SpO2 of the sequential acupoint stimulation group were significantly higher than those of the routine nursing group (P < .05). On both the third day and fifth day after VATS, PCT of the sequential acupoint stimulation group was significantly lower than that of the routine nursing group (P < .01). Furthermore, the difference in postoperative drainage volume between the 2 groups was not statistically significant (P > .05), while chest tube drainage time (P < .01) and postoperative hospitalization days (P < .05) of the sequential acupoint stimulation group were significantly lower than those of the routine nursing group.In spontaneous pneumothorax patients who underwent VATS, sequential acupoint stimulation nursing was significantly more effective than routine postoperative nursing in promoting postoperative recovery of lung function, alleviating inflammatory response and shortening hospitalization days.