High resolution Tibetan Plateau regional reanalysis 1961-present.

With the rapid global warming in recent decades, the Tibetan Plateau (TP) has suffered severe impacts, such as glacier retreat, glacial lake expansion, and permafrost degradation, which threaten the lives and properties of the local and downstream populations. Regional Reanalysis (RR) is vital for TP due to the limitations of observations. In this work, a 62-year (1961-2022) long atmospheric regional reanalysis with spatial resolution of 9 km (convective gray-zone scale) and temporal resolution of 1 hour over the TP (TPRR) was developed using the Weather Research and Forecasting (WRF) model, combined with re-initialization method, spectral nudging (SN), and several optimizations. TPRR is forced by ERA5 at hourly intervals. TPRR outperforms ERA5, realistically capturing climatological characteristics and seasonal variations of precipitation and T2m (air temperature at 2m above ground level). Moreover, TPRR better reproduces the frequency and intensity of precipitation, as well as the diurnal cycle of precipitation. This study also quantifies the wetting trend of 0.0071 mm/year over the TP amid global warming using TPRR.

Neurotoxic Impact of Individual Anesthetic Agents on the Developing Brain.

Concerns about the safety of anesthetic agents in children arose after animal studies revealed disruptions in neurodevelopment after exposure to commonly used anesthetic drugs. These animal studies revealed that volatile inhalational agents, propofol, ketamine, and thiopental may have detrimental effects on neurodevelopment and cognitive function, but dexmedetomidine and xenon have been shown to have neuroprotective properties. The neurocognitive effects of benzodiazepines have not been extensively studied, so their effects on neurodevelopment are undetermined. However, experimental animal models may not truly represent the pathophysiological processes in children. Multiple landmark studies, including the MASK, PANDA, and GAS studies have provided reassurance that brief exposure to anesthesia is not associated with adverse neurocognitive outcomes in infants and children, regardless of the type of anesthetic agent used.

Global spatiotemporally continuous MODIS land surface temperature dataset.

Land surface temperature (LST) plays a critical role in land surface processes. However, as one of the effective means for obtaining global LST observations, remote sensing observations are inherently affected by cloud cover, resulting in varying degrees of missing data in satellite-derived LST products. Here, we propose a solution. First, the data interpolating empirical orthogonal functions (DINEOF) method is used to reconstruct invalid LSTs in cloud-contaminated areas into ideal, clear-sky LSTs. Then, a cumulative distribution function (CDF) matching-based method is developed to correct the ideal, clear-sky LSTs to the real LSTs. Experimental results prove that this method can effectively reconstruct missing LST data and guarantee acceptable accuracy in most regions of the world, with RMSEs of 1-2 K and R values of 0.820-0.996 under ideal, clear-sky conditions and RMSEs of 4-7 K and R values of 0.811-0.933 under all weather conditions. Finally, a spatiotemporally continuous MODIS LST dataset at 0.05° latitude/longitude grids is produced based on the above method.

Spatial and temporal variations in global soil respiration and their relationships with climate and land cover.

Soil respiration (R s) represents the largest flux of CO2 from terrestrial ecosystems to the atmosphere, but its spatial and temporal changes as well as the driving forces are not well understood. We derived a product of annual global R s from 2000 to 2014 at 1 km by 1 km spatial resolution using remote sensing data and biome-specific statistical models. Different from the existing view that climate change dominated changes in R s, we showed that land-cover change played a more important role in regulating R s changes in temperate and boreal regions during 2000-2014. Significant changes in R s occurred more frequently in areas with significant changes in short vegetation cover (i.e., all vegetation shorter than 5 m in height) than in areas with significant climate change. These results contribute to our understanding of global R s patterns and highlight the importance of land-cover change in driving global and regional R s changes.

Preoperative Predictive Factors of Positive Margin Status After Breast Conserving Therapy (BCT) with Intraoperative Radiation Therapy (IORT): A Retrospective Study of 400 Patients.

INTRODUCTION: Single-fraction intraoperative radiation therapy (IORT) has emerged as a therapeutic option in patients undergoing breast conserving therapy (BCT) for early stage breast cancer, often eliminating the need for postoperative external beam radiation therapy. However, if a positive margin is encountered after BCT, the patient will ultimately require external beam radiation therapy. The purpose of this study was to identify preoperative factors from patient demographics, preoperative workup, or biopsy results that may be predictive of postoperative margin status. MATERIALS AND METHODS: A retrospective chart review was performed on 396 patients who underwent BCT with IORT. Logistic regression models were utilized for statistical analysis. RESULTS: The majority of studied variables were similar; however, differences were noted for high-grade tumors, in situ status, and progesterone receptor-negative (PR-) tumors. Grade 3 tumors were significantly associated with positive margin status when compared with Grade 1 (odds ratio, 2.30; P = .036). PR- status tumors were found to be approximately 2 times more likely to have a positive margin (P = .028). Patients with in situ (stage 0) status tumors were 1.986 times more likely to have positive margins when compared with those with an invasive tumor (P = .030). CONCLUSIONS: Higher grade PR- tumors are at increased risk of having a positive margin, which should be taken into consideration when considering treatment with IORT.

Accuracy of subjective vesicoureteral reflux timing assessment: supporting new voiding cystourethrogram guidelines.

BACKGROUND: Bladder volume at the onset of vesicoureteral reflux (VUR) is an important prognostic indicator of spontaneous resolution and the risk of pyelonephritis. OBJECTIVE: We aim to determine whether pediatric urologists and pediatric radiologists can accurately estimate the timing of reflux by examining voiding cystourethrogram (VCUG) images without prior knowledge of the instilled contrast volume. MATERIALS AND METHODS: Total bladder volume and the volume at the time of reflux were collected from VCUG reports to determine the volume at the onset of VUR. Thirty-nine patients were sorted into three groups: early-/mid-filling reflux, late-filling and voiding only. Thirty-nine images were shown to three pediatric urologists and two pediatric radiologists in a blinded fashion and they were then asked to estimate VUR timing based on the above categories. A weighted kappa statistic was calculated to assess rater agreement with the gold standard volume-based report of VUR timing. RESULTS: The mean patient age at VCUG was 3.1±2.9 months, the median VUR was grade 3, and 20 patients were female. Overall agreement among all five raters was moderate (k=0.43, 95% confidence interval [CI] 0.36-0.50). Individual agreement between rater and gold standard was slight to moderate with kappa values ranging from 0.13 to 0.43. CONCLUSION: Pediatric radiologists and urologists are unable to accurately and reliably characterize VUR timing on fluoroscopic VCUG. These findings support the recently published American Academy of Pediatrics protocol recommending the routine recording of bladder volume at the onset of VUR as a standard component of all VCUGs to assist in a more accurate assessment of the likelihood of resolution and risk of recurrent urinary tract infections.

Catheter-Directed Pharmacologic Thrombolysis for Acute Submassive and Massive Pulmonary Emboli in Children and Adolescents-An Exploratory Report.

OBJECTIVES: The objective of this study is to report a single-center experience of the safety and efficacy of pulmonary artery catheter-directed thrombolysis for both massive and submassive pulmonary emboli in the pediatric and adolescent population. DESIGN: A 22-month retrospective review of the electronic medical record and picture archiving and communication system was performed of patients less than 21 years old, presenting with massive or submassive pulmonary emboli treated with pulmonary artery catheter-directed thrombolysis at a single, tertiary care pediatric hospital. Multiple variables were analyzed including indications, technical success, clinical efficacy, and complications. SETTING: A single, tertiary care pediatric hospital. PATIENTS: Nine patients (mean 13.9 yr; range 6-19 yr) with massive and/or submassive pulmonary emboli who underwent pulmonary artery catheter-directed thrombolysis met inclusion criteria. INTERVENTIONS: Catheter-directed thrombolysis. MEASUREMENTS AND MAIN RESULTS: Pulmonary emboli was diagnosed by CT angiography in all cases. Catheter-directed thrombolysis alone was clinically successful (defined as improved cardiopulmonary function following catheter-directed thrombolysis) in seven patients (78%) with two patients not improving following catheter-directed thrombolysis. There were no immediate bleeding complications from catheter-directed thrombolysis therapy. All patients were maintained on anticoagulation treatment following catheter-directed thrombolysis. Catheter-directed thrombolysis was technically successful (defined as successful placement of pulmonary artery infusion catheters with full or partial resolution of thrombus) in all cases. Follow-up pulmonary angiography at the cessation of catheter-directed thrombolysis revealed complete thrombus resolution in four patients (44%) and partial resolution in five patients (55%). Mean pulmonary artery pressures decreased in all patients (mean precatheter-directed thrombolysis pulmonary artery pressure = 37 ± 11 mm Hg; mean postcatheter-directed thrombolysis pulmonary artery pressure = 28 ± 10 mm Hg; p = 0.0164). CONCLUSIONS: Pulmonary artery catheter-directed thrombolysis is a technically feasible therapeutic option for children and adolescents with submassive and massive pulmonary emboli.

Wide variation in caffeine discontinuation timing in premature infants.

OBJECTIVE: To assess site variability and concomitant respiratory support related to the timing of caffeine discontinuation, and compare clinical characteristics of infants who discontinued caffeine before vs. within the last week of hospitalization. STUDY DESIGN: Cohort study of 81,110 infants <35 weeks gestational age and <1500 g birth weight discharged from 304 neonatal intensive care units from 2001-2016. RESULTS: The mean postmenstrual age at caffeine discontinuation ranged from 32 to 37 weeks among sites. Respiratory support at the time of discontinuation was common, but variable, with 0-57% of infants receiving positive airway pressure at caffeine discontinuation by site. Infants who discontinued caffeine within the last week of hospitalization had longer total duration of caffeine, but were discharged from the hospital at an earlier postmenstrual age. CONCLUSION: There was substantial variability among sites in the timing of caffeine discontinuation before discharge and respiratory support at the time of caffeine discontinuation.

Pediatric Surgical Risk Assessment Tools: A Systematic Review.

BACKGROUND: Pediatric surgical risk assessment tools use patient- and procedure-specific variables to predict postoperative complications. These tools assist clinicians in preoperative counseling and surgical decision-making. The objective of this systematic literature review was to compile and compare existing pediatric surgical risk tools that are broadly applicable across pediatric surgical specialties. METHODS: A systematic literature review was performed following the Preferred Reporting Items for Systematic Reviews (PRISMA) guidelines. Relevant publications were identified and screened based on predefined eligibility criteria: (1) a preoperative risk assessment tool predicting postoperative complications or mortality, (2) applicable across various surgical specialties, and (3) pertinent to the pediatric population. Studies with specialty- or procedure-specific risk scores and validation studies were excluded. Included articles were assessed for quality and risk of bias by using the Newcastle-Ottawa Scale. RESULTS: Four studies met inclusion criteria. Risk factors were evaluated across the models as proxies for operative suitability of patients before surgery. Risk factors common to all studies were the presence of cardiovascular or neurological diseases and history of prematurity. Three of the four included studies defined most risk factors in binary terms, whereas one study used a scale of severity of organ system disease when defining preoperative risk. Generated risk score models provided good to strong concordance with inpatient mortality or postoperative complications, with c-statistic values ranging from 0.77 to 0.98. CONCLUSIONS: Each study reported an assessment of a novel, generally applicable pediatric surgical risk assessment tool for risk-stratifying children preoperatively for complications that rise after surgery. More studies are needed to assess generalizability in all populations and procedures.

Thrombogenic superior vena cava syndrome from long-standing central venous access in a 5-year-old patient treated with balloon-expandable stents.

Thrombogenic superior vena cava syndrome is an uncommon, dangerous complication of long-standing central venous catheter use. The increased use of central venous catheters has resulted in more non-malignant cases of superior vena cava syndrome across all age groups. We present a 5-year-old male with superior vena cava syndrome associated with acute onset of severe upper extremity and facial swelling, dyspnea, and a right subclavian central venous catheter malfunction. The patient was ultimately treated with percutaneous stenting of the superior vena cava with balloon-expandable Palmaz stents following unsuccessful angioplasty, catheter-directed thrombolysis, and percutaneous thrombectomy. This case highlights a relatively uncommon complication in children from long-term central venous catheter access and describes an emerging, minimally-invasive therapeutic alternative that allows for preservation of age-appropriate superior vena cava luminal diameter as patients grow.

Diurnal cycle and seasonal variation of cloud cover over the Tibetan Plateau as determined from Himawari-8 new-generation geostationary satellite data.

Analysis of cloud cover and its diurnal variation over the Tibetan Plateau (TP) is highly reliant on satellite data; however, the accuracy of cloud detection from both polar-orbiting and geostationary satellites over this area remains unclear. The new-generation geostationary Himawari-8 satellites provide high-resolution spatial and temporal information about clouds over the Tibetan Plateau. In this study, the cloud detection of MODIS and AHI is investigated and validated against CALIPSO measurements. For AHI and MODIS, the false alarm rate of AHI and MODIS in cloud identification over the TP was 7.51% and 1.94%, respectively, and the cloud hit rate was 73.55% and 80.15%, respectively. Using hourly cloud-cover data from the Himawari-8 satellites, we found that at the monthly scale, the diurnal cycle in cloud cover over the TP tends to increase throughout the day, with the minimum and maximum cloud fractions occurring at 10:00 a.m. and 18:00 p.m. local time. Due to the limited time resolution of polar-orbiting satellites, the underestimation of MODIS daytime average cloud cover is approximately 4.00% at the annual scale, with larger biases during the spring (5.40%) and winter (5.90%).

Combining XCO2 measurements derived from SCIAMACHY and GOSAT for potentially generating global CO2 maps with high spatiotemporal resolution.

Global warming induced by atmospheric CO2 has attracted increasing attention of researchers all over the world. Although space-based technology provides the ability to map atmospheric CO2 globally, the number of valid CO2 measurements is generally limited for certain instruments owing to the presence of clouds, which in turn constrain the studies of global CO2 sources and sinks. Thus, it is a potentially promising work to combine the currently available CO2 measurements. In this study, a strategy for fusing SCIAMACHY and GOSAT CO2 measurements is proposed by fully considering the CO2 global bias, averaging kernel, and spatiotemporal variations as well as the CO2 retrieval errors. Based on this method, a global CO2 map with certain UTC time can also be generated by employing the pattern of the CO2 daily cycle reflected by Carbon Tracker (CT) data. The results reveal that relative to GOSAT, the global spatial coverage of the combined CO2 map increased by 41.3% and 47.7% on a daily and monthly scale, respectively, and even higher when compared with that relative to SCIAMACHY. The findings in this paper prove the effectiveness of the combination method in supporting the generation of global full-coverage XCO2 maps with higher temporal and spatial sampling by jointly using these two space-based XCO2 datasets.