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Guangdong Province, a significant wind energy producer in China, is frequently impacted by landing typhoons along its coastal areas. Therefore, it is crucial to analyze the characteristics and influencing factors of wind power generation during typhoons at coastal wind farms in Guangdong. This study examines power generation data from the Lingnan Wind Farm during Typhoon Chaba and calculates indexes including wind shear, temperature and pressure change. Results show that the average power generation of Lingnan Wind Farm was 44.4 MW/h during the study period, and when Typhoon Chaba approaches the wind farm within a proximity of less than 300 km, the average power generation increases by 43%. Conversely, when Chaba is more than 600 km away from the wind farm, the average power generation decreases by 10%. The analysis employing a random forest model identifies wind speed at 80 m height, 24‐h pressure change, and pressure as the most influential factors throughout the study period. This underscores the significance of surface pressure and pressure variations at the wind farm for predicting wind power output at coastal wind farms during a typhoon process. The random forest model yields mean absolute error and root mean square error values of 9.4 MW/h and 11.6 MW/h, respectively, in the prediction of wind power generation. Using wind farm observations, ERA5 reanalysis, and Typhoon datasets, this study examines power generation data from the Lingnan Wind Farm during Typhoon Chaba and calculates indices including wind shear, temperature and pressure change. When ws_80 is below 20 m/s, a rise of 1 m/s in ws_80 results in a corresponding increase in wind power generation of approximately 5.2 MW/h. However, once ws_80 reaches 20 m/s, certain turbines at Lingnan Wind Farm reach their cut‐out wind speed, causing a decline in power generation as ws_80 continues to rise. The analysis employing a random forest model identifies wind speed at 80 m height, 24‐h pressure change, and pressure as the most influential factors throughout the study period. This underscores the significance of surface pressure and pressure variations at the wind farm for predicting wind power output at coastal wind farms during a typhoon process.

The aim of this study was to investigate the effects of different recumbent sleeping positions of the head and body on intraocular pressure (IOP) in secondary open-angle glaucoma and glaucoma suspect patients, specifically pigmentary dispersion (PD) as measured using the ICare rebound tonometer. A total of 44 eyes of 24 patients with PD were selected in this study. The IOP of 44 eyes was measured in the initial seated position, in the 4 recumbent positions, and again in the sitting position between each of the recumbent positions. The IOP of the right eyes and left eyes was higher in each of the 4 recumbent positions compared to its initial sitting position (all <0.001). Dependent (D) vs nondependent (ND) comparisons failed to show a significant difference. All lateral vs prone comparisons showed a higher average IOP in the prone position than in the lateral position regardless of D vs ND status. The range of recumbent IOP changes was -4 to +17 mmHg or -17% to +142%. A total of 64% had at least a ≥33% IOP increase with 43% having a ≥50% increase. Lateral and prone sleeping positions usually do result in significant elevations of IOP in PD patients. Dependency status did not make a difference. A significantly larger IOP increase was seen in the prone position than in the lateral position. The presence of 3 clinical variables (disk hemorrhage [DH], notches, and BV changes) might increase the chances of developing a large recumbent increase in IOP. These patients and possibly all PD syndrome (PDS) or PD glaucoma (PDG) patients should consider sleeping in a bed that allows a head elevation of 30°.

Whether the definition of hypertension according to 2017 AHA/ACC guidelines and blood pressure (BP) changes was related to the increased risk of chronic kidney disease (CKD) remained debated. This prospective cohort study aimed to investigate the association of BP and long‐term BP change with CKD risk with different glucose metabolism according to the new hypertension guidelines. This study examined 12 951 participants and 11 183 participants derived from the older people cohort study, respectively. Participants were divided into three groups based on blood glucose and the risks were assessmented by the logistic regression model. During a 10 years of follow‐up period, 2727 individuals developed CKD (21.1%). Compared with those with BP < 130/80 mmHg, individuals with increased BP levels had significantly increased risk of incident CKD. Participants with BP of 130–139/80–89 or ≥140/90 mmHg had 1.51‐ and 1.89‐fold incident risk of CKD in patients with diabetes mellitus (DM). Compared with individuals with stable BP (−5 to 5 mmHg), the risk of CKD was reduced when BP decreased by 5 mmHg or more and increased when BP increased ≥5 mmHg among normoglycemia and prediabetes participants. Similar results were observed for rapid estimated glomerular filtration rate (eGFR) decline. In conclusion, the BP of 130–139/80–89 mmHg combined with prediabetes or DM had an increased risk of incident CKD and rapid eGFR decline in older people. Long‐term changes of BP by more than 5 mmHg among normoglycemia or prediabetes were associated with the risk of incident CKD and rapid eGFR decline.

NASA’s InSight mission to Mars will measure seismic signals to determine the planet’s interior structure. These highly sensitive seismometers are susceptible to corruption of their measurements by environmental changes. Magnetic fields, atmosphere pressure changes, and local winds can all induce apparent changes in the seismic records that are not due to propagating ground motions. Thus, InSight carries a set of sensors called the Auxiliary Payload Sensor Suite (APSS) which includes a magnetometer, an atmospheric pressure sensor, and a pair of wind and air temperature sensors. In the case of the magnetometer, knowledge of the amplitude of the fluctuating magnetic field at the InSight lander will allow the separation of seismic signals from potentially interfering magnetic signals of either natural or spacecraft origin. To acquire such data, a triaxial fluxgate magnetometer was installed on the deck of the lander to obtain magnetic records at the same cadence as the seismometer. Similarly, a highly sensitive pressure sensor is carried by InSight to enable the removal of local ground-surface tilts due to advecting pressure perturbations. Finally, the local winds (speed and direction) and air temperature are estimated using a hot-film wind sensor with heritage from REMS on the Curiosity rover. When winds are too high, seismic signals can be ignored or discounted. Herein we describe the APSS sensor suite, the test programs for its components, and the possible additional science investigations it enables.

The flow characteristics of the single-phase liquid and the gas–liquid two-phase flows including the Newtonian and non-Newtonian liquids were experimentally investigated in a horizontal rectangular micro-channel with a sudden contraction—specifically the pressure change across the contraction. The rectangular cross-sectional dimension has Wu × Hu (width × height) = 0.99 × 0.50 mm2 on the upstream side of the contraction and Wd × Hd = 0.49 × 0.50 mm2 on the downstream side. The resulting contraction ratio, σA (=Wd/Wu), was 0.5. Air was used as the test gas (in the case of the gas–liquid two-phase flow experiment), distilled water and three kinds of aqueous solution, i.e., glycerin 25 wt%, xanthangum 0.1 wt% and polyacrylamide 0.11 wt% were used as the test liquid. The pressure distribution in the flow direction upstream and downstream of the channel was measured. The pressure change and loss at the sudden contraction were determined from the pressure distribution. In addition, the pressure change data were compared with the calculation by several correlations proposed by various researchers as well as a newly developed correlation in this study. From the comparisons, it was found that calculations by the newly developed correlations agreed well with the measured values within the error of 30%.

Abstract Basal shear stress on hard‐bedded glaciers results from normal stress against bed roughness, which depends on basal water pressure and cavity size. These quantities are related in a steady state but are expected to behave differently under rapid changes in water input, which may lead to a transient frictional response not captured by existing friction laws. Here, we investigate transient friction using Global Positioning System vertical displacement and horizontal velocity observations, basal water pressure measurements, and cavitation model predictions during rain‐induced speed‐up events at Glacier d'Argentière, French Alps. We observe up to a threefold increase in horizontal surface velocity, spatially migrating at rates consistent with subglacial flow drainage, and associated with surface uplift and increased water pressure. We show that frictional changes are mainly driven by changes in water pressure at nearly constant cavity size. We propose a generalized friction law capable of capturing observations in both the transient and steady‐state regimes.

The movement of large, slow-moving, deep-seated landslides is regulated principally by changes in pore-water pressure in the slope. In urban areas, drastic reorganization of the surface and subsurface hydrology—for example, associated with roads, housings or storm drainage—may alter the subsurface hydrology and ultimately the slope stability. Yet our understanding of the influence of slope urbanization on the dynamics of landslides remains elusive. Here we combined satellite and (historical) aerial images to quantify how 70 years of hillslope urbanization changed the seasonal, annual and multi-decadal dynamics of a large, slow-moving landslide located in the tropical environment of the city of Bukavu, Democratic Republic of the Congo. Analysis of week-to-week landslide motion over the past 4.5 years reveals that it is closely tied to pore-water pressure changes, pointing to interacting influences from climate, weathering, tectonics and urban development on the landslide dynamics. Over decadal timescales, we find that the sprawl of urbanized areas led to the acceleration of a large section of the landslide, which was probably driven by self-reinforcing feedbacks involving slope movement, rerouting of surface water flows and pipe ruptures. As hillslopes in many tropical cities are being urbanized at an accelerating pace, better understanding how anthropogenic activity influences surface processes will be vital to effective risk planning and mitigation. A large, slow-moving landslide underlying the city of Bukavu in the Democratic Republic of the Congo has accelerated in recent decades due to hydrological modifications related to urbanization, according to an analysis of aerial photographs and remote-sensing data.

Background： Plantar pressure serves as a key factor for predicting ulceration in the feet of diabetes patients. We designed this study to analyze plantar pressure changes and correlating risk factors in Chinese patients with type 2 diabetes. Methods： We recruited 65 patients with type 2 diabetes. They were invited to participate in the second wave 2 years later. The patients completed identical examinations at the baseline point and 2 years later. We obtained maximum force, maximum pressure, impulse, pressure-time integral, and loading rate values from 10 foot regions. We collected data on six history-based variables, six anthropometric variables, and four metabolic variables of the patients. Results： Over the course of the study, significant plantar pressure increases in some forefoot portions were identified （P 〈 0.05）, especially in the second to forth metatarsal heads. Decreases in heel impulse and pressure-time integral levels were also found （P 〈 0.05）. Plantar pressure parameters increased with body mass index （BMI） levels. Hemoglobin Alc （HbAlc） changes were positively＇ correlated with maximum force （β = 0.364, P = 0.001） and maximum pressure （β= 0.366, P = 0.002） changes in the first metatarsal head. Cholesterol changes were positively correlated with impulse changes in the lateral portion of the heel （β = 0.179, P = 0.072） and pressure-time integral changes in the second metatarsal head （β = 0.236, P = 0.020）. Ankle-brachial index （ABI） changes were positively correlated with maximum force changes in the first metatarsal head （β = 0.137, P = 0.048）. Neuropathy symptom score （NSS） and common peroneal nerve sensory nerve conduction velocity （SCV） changes were positively correlated with some plantar pressure changes. In addition, plantar pressure changes had a correlation with the appearance of infections, blisters （β = 0.244, P = 0.014）, and calluses over the course of the study. Conclusions： We should pay attention to the BMI, HbAlc, cholesterol, ABI, SCV, and NSS changes in the process of preventing high plantar pressure and ulceration. Some associated precautions may be taken with the appearance of infections, blisters, and calluses.

This study introduces a technique for four‐dimensional pore pressure monitoring using passive image interferometry. Surface‐wave velocity changes as a function of frequency are directly linked to depth variations of pore pressure changes through sensitivity kernels. We demonstrate that these kernels can be used to invert time‐lapse seismic velocity changes, retrieved with passive image interferometry, for hydrological pore pressure variations as a function of time, depth, and region. This new approach is applied in the Groningen region of the Netherlands. We show good recovery of pore pressure variations in the upper 200 m of the subsurface from passive seismic velocity observations. This depth range is primarily limited by the reliable frequency range of the seismic data. Plain Language Summary In this study, we develop a method for pore pressure monitoring using seismic ambient noise. We use passive image interferometry to estimate surface‐wave velocity changes as a function of frequency, and compute for surface‐wave velocities the sensitivity to pore pressure changes as a function of depth. These so‐called pore pressure sensitivity kernels are then used to invert surface‐wave velocity changes for pore pressure variations as a function of depth. By comparing different regions of Groningen, The Netherlands, we build a four‐dimensional pore pressure model for the shallowest 200 m of the subsurface. While the hydrological pore pressure variation can continue beyond 200 m depth, our method is limited by the shallow sensitivity and the frequency ranges for which seismic velocity measurements are possible. Key Points Surface‐wave velocity changes are directly linked to pore pressure variations through sensitivity kernels Pore pressure sensitivity kernels enable an inversion of surface‐wave velocity changes for 4D pore pressure variations The shallow sensitivity to pore pressure changes in Groningen limits the method to the upper 200 m of the subsurface

Flow of cerebrospinal fluid (CSF) in perivascular spaces (PVS) is one of the key concepts involved in theories concerning clearance from the brain. Experimental studies have demonstrated both net and oscillatory movement of microspheres in PVS (Mestre et al. (2018), Bedussi et al. (2018)). The oscillatory particle movement has a clear cardiac component, while the mechanisms involved in net movement remain disputed. Using computational fluid dynamics, we computed the CSF velocity and pressure in a PVS surrounding a cerebral artery subject to different forces, representing arterial wall expansion, systemic CSF pressure changes and rigid motions of the artery. The arterial wall expansion generated velocity amplitudes of 60–260 μ m/s, which is in the upper range of previously observed values. In the absence of a static pressure gradient, predicted net flow velocities were small (<0.5 μ m/s), though reaching up to 7 μ m/s for non-physiological PVS lengths. In realistic geometries, a static systemic pressure increase of physiologically plausible magnitude was sufficient to induce net flow velocities of 20–30 μ m/s. Moreover, rigid motions of the artery added to the complexity of flow patterns in the PVS. Our study demonstrates that the combination of arterial wall expansion, rigid motions and a static CSF pressure gradient generates net and oscillatory PVS flow, quantitatively comparable with experimental findings. The static CSF pressure gradient required for net flow is small, suggesting that its origin is yet to be determined.