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Abstract Atmospheric prediction at 2–6 weeks lead time (so‐called subseasonal‐to‐seasonal timescales) entails large forecast uncertainty. Here we investigate the flow‐dependence of this uncertainty during Boreal winter. We categorize the large‐scale flow using North Atlantic‐European weather regimes. First, we show that forecast uncertainty of near‐surface geopotential height (Z1000) and temperature (T2m) are strongly sensitive to the prevailing regime. Specifically, forecast uncertainty of Z1000 reduces over northern Europe following Greenland Blocking (enhanced predictability) due to a southward shifting eddy‐driven jet. However, due to strong temperature gradients and variable flow patterns, Greenland blocking is linked to increased forecast uncertainty of T2m over Europe (reduced predictability). Second, we show that forecast uncertainty of weather regimes is modulated via the stratospheric polar vortex. Weak polar vortex states tend to reduce regime‐uncertainty, for example, due to more frequent predicted occurrence of Greenland blocking. These regime changes are associated with increased T2m uncertainty over Europe.

Abstract Background Peripheral nerve sheath tumors (PNSTs) are a group of neoplasms originating from Schwann cells or pluripotent cell of the neural crest. Therapeutic options and prognosis are influenced by their degree of malignancy and location. Hypothesis/Objectives Identify magnetic resonance imaging (MRI) features predictive of PNST histologic grade. Animals Forty‐four dogs with histopathological diagnosis of spinal PNSTs and previous MRI investigation. Methods A multicenter retrospective study including cases with (a) histopathologic diagnosis of PNST and (b) MRI studies available for review. Histologic slides were reviewed and graded by a board‐certified pathologist according to a modified French system (FNCLCC) for grading soft tissue sarcomas. The MRI studies were reviewed by 2 board‐certified radiologists blinded to the grade of the tumor and the final decision on the imaging characteristics was reached by consensus. Relationships between tumor grade and histological and MRI findings were assessed using statistical analysis. Results Forty‐four cases met inclusion criteria; 16 patients were PNSTs Grade 1 (low‐grade), 19 were PNSTs Grade 2 (medium‐grade), and 9 were PNSTs Grade 3 (high‐grade). Large volume (P = .03) and severe peripheral contrast enhancement (P = .04) were significantly associated with high tumor grade. Degree of muscle atrophy, heterogeneous signal and tumor growth into the vertebral canal were not associated with grade. Conclusions and Clinical Importance Grade of malignancy was difficult to identify based on diagnostic imaging alone. However, some MRI features were predictive of high‐grade PNSTs including tumor size and peripheral contrast enhancement.

Abstract Background The significance of different histological spreading patterns of tumor tissue in oral tongue squamous cell carcinoma (TSCC) is well known. Our aim was to construct a numeric parameter on a continuous scale, that is, the modified Polsby–Popper (MPP) score, to describe the aggressiveness of tumor growth and infiltration, with the potential to analyze hematoxylin and eosin‐stained whole slide images (WSIs) in an automated manner. We investigated the application of the MPP score in predicting survival and cervical lymph node metastases as well as in determining patients at risk in the context of different surgical margin scenarios. Methods We developed a semiautomated image analysis pipeline to detect areas belonging to the tumor tissue compartment. Perimeter and area measurements of all detected tissue regions were derived, and a specific mathematical formula was applied to reflect the perimeter/area ratio in a comparable, observer‐independent manner across digitized WSIs. We demonstrated the plausibility of the MPP score by correlating it with well‐established clinicopathologic parameters. We then performed survival analysis to assess the relevance of the MPP score, with an emphasis on different surgical margin scenarios. Machine learning models were developed to assess the relevance of the MPP score in predicting survival and occult cervical nodal metastases. Results The MPP score was associated with unfavorable tumor growth and infiltration patterns, the presence of lymph node metastases, the extracapsular spread of tumor cells, and higher tumor thickness. Higher MPP scores were associated with worse overall survival (OS) and tongue carcinoma‐specific survival (TCSS), both when assessing all pT‐categories and pT1‐pT2 categories only; moreover, higher MPP scores were associated with a significantly worse TCSS in cases where a cancer‐free surgical margin of

Abstract Background Fine‐needle aspiration cytology (FNAC) represents an important diagnostic tool for the workup of salivary gland (SG) lesions. The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) is a six‐tiered system for standardizing diagnoses and improvement of communication between pathologists and clinicians, providing risk of malignancy (ROM) rates for every category. The aims of the present study were (i) to validate the use of MSRSGC in a large series of SG FNAC in a tertiary center in Switzerland, (ii) to determine ROM for each category and compare them with data from MSRSGC and similar studies, and (iii) to investigate whether there were relevant differences of non‐diagnostic results between fine‐needle aspirations (FNA) performed by cytopathologists compared to non‐cytopathologists. Methods The files of the department of Pathology in the University Hospital Zurich (UHZ) were searched for SG FNAC between 2010 and 2019. The MSRSGC guidelines were applied retrospectively. Furthermore, ROM, risk of neoplasia (RON), sensitivity, and specificity were calculated based on the cases with histopathological follow‐up. Results A total of 2156 SG FNAC including 753 cases with histopathological follow‐up were evaluated. Generally, ROM was within the range of values provided by MSRSGC, with some minor deviations. Sensitivity was 94.6%, and specificity was 99.3%. Conclusions Our study confirms the usefulness of MSRSGC. In addition, it provides a detailed insight into the wide spectrum of SG FNAC. Finally, we showed that the rate of non‐diagnostic FNA was significantly lower in FNAs performed by cytopathologists compared to non‐cytopathologists.

While organ‐confined prostate cancer (PCa) is mostly therapeutically manageable, metastatic progression of PCa remains an unmet clinical challenge. Resistance to anoikis, a form of cell death initiated by cell detachment from the surrounding extracellular matrix, is one of the cellular processes critical for PCa progression towards aggressive disease. Therefore, further understanding of anoikis regulation in PCa might provide therapeutic opportunities. Here, we discover that PCa tumours with concomitant inhibition of two tumour suppressor phosphatases, PP2A and PTEN, are particularly aggressive, having

Abstract Objective Serum neurofilament light chain (sNfL) is a biomarker for neuroaxonal damage and has been found to be elevated in several neurological diseases with neuronal destruction. New onset of confusion is a hallmark of severity in infections. The objective of this study was to determine whether sNfL levels are increased in patients with community‐acquired pneumonia (CAP) and if increased sNfL levels are associated with disease‐associated confusion or disease severity. Methods In this observational study, sNfL levels were determined with single‐molecule array technology in CAP patients of the CAPNETZ cohort with validated CRB (confusion, respiratory rate, and blood pressure)‐65 score. We determined associations between log‐transformed sNfL concentrations, well‐defined clinical characteristics, and unfavorable outcome in multivariable analyses. Receiver operating characteristic (ROC) analysis was performed to assess the prediction accuracy of sNfL levels for confusion in CAP patients. Results sNfL concentrations were evaluated in 150 CAP patients. Patients with confusion had higher sNfL levels as compared to non‐confusion patients of comparable overall disease severity. ROC analysis of sNfL and confusion provided an area under the curve (AUC) of 0.73 (95% CI 0.62–0.82). Log‐transformed sNfL levels were not associated with general disease severity. In a logistic regression analysis, log2‐sNfL was identified as a strong predictor for an unfavorable outcome. Interpretation sNfL levels are specifically associated with confusion and not with pneumonia disease severity, thus reflecting a potential objective marker for encephalopathy in these patients. Furthermore, sNfL levels are also associated with unfavorable outcome in these patients and might help clinicians to identify patients at risk.

Abstract Sudden stratospheric warming (SSW) events can form a window of forecast opportunity for polar vortex predictions on subseasonal‐to‐seasonal time scales. Analyzing numerical ensemble simulations, we quantify the associated enhanced predictability due to reduced upward planetary wave fluxes during the mostly radiatively driven recovery phase following SSWs. Ensembles that predict an SSW show reduced ensemble spread in terms of polar vortex strength for several weeks to follow, as well as a corresponding reduction in forecast errors. This increased predictability is particularly pronounced for strong SSWs and even occurs if not all ensemble members predict a major SSW. Furthermore, we found a direct impact of the occurrence of SSWs on the date of the final warming (FW): the decrease in upward wave fluxes delays the FW significantly. The reduced spread after SSWs and the delay in FW date have potentially further implications for (subseasonal) predictions of the tropospheric and mesospheric circulations.

Abstract Mean annual air temperature has been increasing in Alaska since the 1970s and is expected to continue to increase through the current century, resulting in significant environmental changes (e.g., permafrost thaw, shifts in vegetation community composition and distribution, increased wildfire frequency and severity). Because there is little long‐term monitoring data available on lake ecosystems in the subarctic it is difficult to predict how lakes will respond. Here we present data from an ~20‐year long‐term lake and climate monitoring program in Interior Alaska. A significant portion of the lake catchment was burned by wildfires in 1986 and again in 2004. As a result, much of the vegetation in the lake catchment was converted from spruce‐dominated forest to deciduous forest, indicating likely permafrost degradation. At a nearby monitoring site absent of fire effects, mean annual ground temperatures at 50 and 90 cm warmed significantly from about −2°C to about −1°C over the 20‐year monitoring period. Warming of similar or greater magnitude is inferred at the study site due to fire effects. Lake water analyses before and after the 2004 fire show a significant postfire increase in dissolved organic carbon, total nitrogen, and total phosphorous that persisted for a short period (~3 years) and was followed by small, but significant, increases in specific conductance and ion concentrations. Approximately 15 years postfire sulfate and cation concentrations in the lake increased exponentially due to the development of a groundwater seep near the lake. The seep likely formed as a result of permafrost thaw creating new subsurface flowpaths in response to long‐term climate warming and fire effects. In 2021, specific conductance and sulfate concentrations reached 657 μS/cm and 71 mg/L respectively, exceeding tolerance thresholds of the water lily Nuphar lutea. In 2021, N. lutea beds that had occupied the lake since 1981 were no longer visible. Depending on local catchment characteristics, source waters and flow paths contributing to small subarctic lakes will continue to evolve uniquely in response to climate change and thawing permafrost. This case study shows the cascading effects of warming soil and wildfires on catchment characteristics as well as terrestrial and aquatic vegetation and lake water chemistry.

Abstract Issues of energy efficiency, latency and reliability have engaged researchers' attention in wireless communications for a long time due to their importance in the dependable delivery of data over wireless networks. The emergence of M2M communication and IoT has intensified this attention because energy efficiency and latency are critical factors affecting their performance. In this paper, a scheduler is designed by utilising the probability density function of the signal‐to‐noise ratio of Rayleigh fading channels to define a threshold used for resource allocation. This threshold, combined with the mean SNR of an M2M device, determines whether or not an M2M device is eligible for scheduling, given its instantaneous channel conditions. The trade‐off between energy efficiency, latency and packet drop of this proposed scheduling strategy is investigated. The performance of the proposed scheduler is compared to round robin, maximum throughput, and proportional fair schedulers. Compared to these standard scheduling strategies, the scheduler provides the advantage of trading off latency for energy efficiency by tuning the threshold parameter.

Abstract Purpose To determine the 50 most cited studies on posterior tibial slope (PTS) in joint preserving knee surgery and assess their level of evidence, objective study quality scores as well as to examine whether the study quality correlated with the citation count and citation density in the top 50 list. Methods A literature search on Web of Science was performed to determine the 50 most cited studies on the topic of PTS in joint preserving knee surgery between 1990 and 2022. The studies were evaluated for their bibliographic parameters, level of evidence rating (LOE), citation counts, the Modified Coleman Methodological Score (MCMS), the Methodological Index for Non‐Randomized Studies (MINORS), and the Radiologic Methodology and Quality Scale (MQCSRE). Results Of the top 50 list, 16 studies were published in the American Journal of Sports Medicine. A total of 23 studies were produced in the United States (46%). Of 10 different study types, case control studies (n = 16, 32%) and cadaveric studies (n = 10, 20%) were most common. 15 studies (30%) were purely radiological studies. 6 studies were level II (12%), 23 level III (46%), 15 level IV (30%), and 6 level V studies (12%), respectively. The number of citations ranged from 42 to 447 (mean 105.6 ± 79.2 citations) and showed a mean citation density of 10.3 ± 5.2, composed of the decades 1994 – 2000 (8.3 ± 4.1), 2001 – 2010 (11.1 ± 5.9), 2011 – 2019 (10.1 ± 5.1). Mean quality scores were 55.9 ± 13.0 for MCMS (n = 18), 14.5 ± 3.2 for MINORS (n = 18) and 18.1 ± 3.7 for MQCSRE (n = 20), respectively. High citation counts did not correlate with higher study quality scores (p > 0.05). Radiological studies were not significantly cited more often than non‐radiological studies (mean 116.9 ± 88.3 vs. 100.8 ± 75.8 citations; p > 0.05). Conclusion In joint preserving knee surgery, the 50 most cited studies on PTS did not represent a ranking of the highest methodological quality scores. Citation counts and citation density over the past three decades did not significantly differ, even though the number of articles in the presented list multiplied over the same period. This list can serve as a reference tool for orthopedic surgeons aiming to review PTS literature.