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  1. Book ; Online: Regression modelling of spatiotemporal extreme U.S. wildfires via partially-interpretable neural networks

    Richards, Jordan / Huser, Raphaël

    2022  

    Abstract: Risk management in many environmental settings requires an understanding of the mechanisms that drive extreme events. Useful metrics for quantifying such risk are extreme quantiles of response variables conditioned on predictor variables that describe, e. ...

    Abstract Risk management in many environmental settings requires an understanding of the mechanisms that drive extreme events. Useful metrics for quantifying such risk are extreme quantiles of response variables conditioned on predictor variables that describe, e.g., climate, biosphere and environmental states. Typically these quantiles lie outside the range of observable data and so, for estimation, require specification of parametric extreme value models within a regression framework. Classical approaches in this context utilise linear or additive relationships between predictor and response variables and suffer in either their predictive capabilities or computational efficiency; moreover, their simplicity is unlikely to capture the truly complex structures that lead to the creation of extreme wildfires. In this paper, we propose a new methodological framework for performing extreme quantile regression using artificial neutral networks, which are able to capture complex non-linear relationships and scale well to high-dimensional data. The ``black box" nature of neural networks means that they lack the desirable trait of interpretability often favoured by practitioners; thus, we unify linear, and additive, regression methodology with deep learning to create partially-interpretable neural networks that can be used for statistical inference but retain high prediction accuracy. To complement this methodology, we further propose a novel point process model for extreme values which overcomes the finite lower-endpoint problem associated with the generalised extreme value class of distributions. Efficacy of our unified framework is illustrated on U.S. wildfire data with a high-dimensional predictor set and we illustrate vast improvements in predictive performance over linear and spline-based regression techniques.
    Keywords Statistics - Machine Learning ; Computer Science - Machine Learning ; Statistics - Methodology
    Subject code 310
    Publishing date 2022-08-16
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  2. Article: Recurrent heterotopic ossification following open radical nephrectomy.

    Richards, Jordan R / McElree, Ian M / Orzel, Joanna / Smith, Mark C / Packiam, Vignesh T

    Urology case reports

    2023  Volume 50, Page(s) 102515

    Abstract: A 46-year-old male presented with a localized left renal mass and underwent an open radical nephrectomy via a midline incision. He recovered uneventfully and was discharged. After one month he reported persistent incisional pain; CT demonstrated ... ...

    Abstract A 46-year-old male presented with a localized left renal mass and underwent an open radical nephrectomy via a midline incision. He recovered uneventfully and was discharged. After one month he reported persistent incisional pain; CT demonstrated heterotopic bone formation under the fascial closure. He underwent resection of calcified preperitoneal fat. Final pathology revealed benign bone tissue. He received a course of celecoxib. The patient developed recurrence of a smaller calcification. He underwent a second resection and was treated with adjuvant radiation. The patient had improvement of pain and no ossification visualized on CT imaging at 1-year follow up.
    Language English
    Publishing date 2023-08-05
    Publishing country United States
    Document type Case Reports
    ZDB-ID 2745459-9
    ISSN 2214-4420
    ISSN 2214-4420
    DOI 10.1016/j.eucr.2023.102515
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  3. Book ; Online: Insights into the drivers and spatio-temporal trends of extreme Mediterranean wildfires with statistical deep-learning

    Richards, Jordan / Huser, Raphaël / Bevacqua, Emanuele / Zscheischler, Jakob

    2022  

    Abstract: Extreme wildfires continue to be a significant cause of human death and biodiversity destruction within countries that encompass the Mediterranean Basin. Recent worrying trends in wildfire activity (i.e., occurrence and spread) suggest that wildfires are ...

    Abstract Extreme wildfires continue to be a significant cause of human death and biodiversity destruction within countries that encompass the Mediterranean Basin. Recent worrying trends in wildfire activity (i.e., occurrence and spread) suggest that wildfires are likely to be highly impacted by climate change. In order to facilitate appropriate risk mitigation, it is imperative to identify the main drivers of extreme wildfires and assess their spatio-temporal trends, with a view to understanding the impacts of global warming on fire activity. To this end, we analyse the monthly burnt area due to wildfires over a region encompassing most of Europe and the Mediterranean Basin from 2001 to 2020, and identify high fire activity during this period in eastern Europe, Algeria, Italy and Portugal. We build an extreme quantile regression model with a high-dimensional predictor set describing meteorological conditions, land cover usage, and orography, for the domain. To model the complex relationships between the predictor variables and wildfires, we make use of a hybrid statistical deep-learning framework that allows us to disentangle the effects of vapour-pressure deficit (VPD), air temperature, and drought on wildfire activity. Our results highlight that whilst VPD, air temperature, and drought significantly affect wildfire occurrence, only VPD affects extreme wildfire spread. Furthermore, to gain insights into the effect of climate change on wildfire activity in the near future, we perturb VPD and temperature according to their observed trends and find evidence that global warming may lead to spatially non-uniform changes in wildfire activity.
    Keywords Statistics - Applications ; Statistics - Machine Learning
    Subject code 910
    Publishing date 2022-12-04
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  4. Article: Combined robotic radical prostatectomy and laparoscopic proctectomy for synchronous prostate and rectal cancer.

    Tully, Zachary / Richards, Jordan / Masson, Asgeir T / Guyton, Kristina L / Packiam, Vignesh T

    Urology case reports

    2022  Volume 42, Page(s) 102043

    Abstract: Prostatic adenocarcinoma is the second most common cause of cancer related mortality in men. Robotic-assisted laparoscopic prostatectomy represents a standard treatment option for localized disease. We present a case of a 63-year-old male with ... ...

    Abstract Prostatic adenocarcinoma is the second most common cause of cancer related mortality in men. Robotic-assisted laparoscopic prostatectomy represents a standard treatment option for localized disease. We present a case of a 63-year-old male with synchronous presentation of prostate and rectal cancer treated with combined robotic prostatectomy (RALP) and low anterior resection (LAR). Interestingly, a mesorectal lymph node contained metastatic prostate cancer.
    Language English
    Publishing date 2022-02-25
    Publishing country United States
    Document type Case Reports
    ZDB-ID 2745459-9
    ISSN 2214-4420
    ISSN 2214-4420
    DOI 10.1016/j.eucr.2022.102043
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Book ; Online: Joint Estimation of Extreme Spatially Aggregated Precipitation at Different Scales through Mixture Modelling

    Richards, Jordan / Tawn, Jonathan A. / Brown, Simon

    2021  

    Abstract: Although most models for rainfall extremes focus on point-wise values, it is aggregated precipitation over areas up to river catchment scale that is of the most interest. To capture the joint behaviour of precipitation aggregates evaluated at different ... ...

    Abstract Although most models for rainfall extremes focus on point-wise values, it is aggregated precipitation over areas up to river catchment scale that is of the most interest. To capture the joint behaviour of precipitation aggregates evaluated at different spatial scales, parsimonious and effective models must be built with knowledge of the underlying spatial process. Precipitation is driven by a mixture of processes acting at different scales and intensities, e.g., convective and frontal, with extremes of aggregates for typical catchment sizes arising from extremes of only one of these processes, rather than a combination of them. High-intensity convective events cause extreme spatial aggregates at small scales but the contribution of lower-intensity large-scale fronts is likely to increase as the area aggregated increases. Thus, to capture small to large scale spatial aggregates within a single approach requires a model that can accurately capture the extremal properties of both convective and frontal events. Previous extreme value methods have ignored this mixture structure; we propose a spatial extreme value model which is a mixture of two components with different marginal and dependence models that are able to capture the extremal behaviour of convective and frontal rainfall and more faithfully reproduces spatial aggregates for a wide range of scales. Modelling extremes of the frontal component raises new challenges due to it exhibiting strong long-range extremal spatial dependence. Our modelling approach is applied to fine-scale, high-dimensional, gridded precipitation data. We show that accounting for the mixture structure improves the joint inference on extremes of spatial aggregates over regions of different sizes.
    Keywords Statistics - Applications ; Statistics - Methodology
    Subject code 910
    Publishing date 2021-11-16
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  6. Book ; Online: Modelling Extremes of Spatial Aggregates of Precipitation using Conditional Methods

    Richards, Jordan / Tawn, Jonathan A. / Brown, Simon

    2021  

    Abstract: Inference on the extremal behaviour of spatial aggregates of precipitation is important for quantifying river flood risk. There are two classes of previous approach, with one failing to ensure self-consistency in inference across different regions of ... ...

    Abstract Inference on the extremal behaviour of spatial aggregates of precipitation is important for quantifying river flood risk. There are two classes of previous approach, with one failing to ensure self-consistency in inference across different regions of aggregation and the other imposing highly restrictive assumptions. To overcome these issues, we propose a model for high-resolution precipitation data, from which we can simulate realistic fields and explore the behaviour of spatial aggregates. Recent developments have seen spatial extensions of the Heffernan and Tawn (2004) model for conditional multivariate extremes, which can handle a wide range of dependence structures. Our contribution is twofold: extensions and improvements of this approach and its model inference for high-dimensional data; and a novel framework for deriving aggregates addressing edge effects and sub-regions without rain. We apply our modelling approach to gridded East-Anglia, UK precipitation data. Return-level curves for spatial aggregates over different regions of various sizes are estimated and shown to fit very well to the data.
    Keywords Statistics - Methodology ; Statistics - Applications
    Subject code 910
    Publishing date 2021-02-22
    Publishing country us
    Document type Book ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  7. Article ; Online: The current landscape of salvage therapies for patients with bacillus Calmette-Guérin unresponsive nonmuscle invasive bladder cancer.

    Packiam, Vignesh T / Richards, Jordan / Schmautz, Maximilian / Heidenreich, Axel / Boorjian, Stephen A

    Current opinion in urology

    2021  Volume 31, Issue 3, Page(s) 178–187

    Abstract: Purpose of review: Although radical cystectomy represents the gold standard treatment for patients with high-risk nonmuscle invasive bladder cancer (NMIBC) whose disease does not respond to bacillus Calmette-Guérin (BCG), many patients are unable or ... ...

    Abstract Purpose of review: Although radical cystectomy represents the gold standard treatment for patients with high-risk nonmuscle invasive bladder cancer (NMIBC) whose disease does not respond to bacillus Calmette-Guérin (BCG), many patients are unable or unwilling to undergo surgery. The need remains for effective bladder-preserving therapies. This review aims to describe existing treatments, contemporary research in this field and ongoing trials of salvage therapies for patients with BCG-unresponsive NMIBC.
    Recent findings: Intravesical chemotherapy has been utilized frequently in this setting. Emerging data on combination regimens such as intravesical gemcitabine and docetaxel and intravesical cabazitaxel, gemcitabine and cisplatin are promising; nevertheless, larger, prospective trials are needed. Meanwhile, the intravenous checkpoint inhibitor pembrolizumab was recently FDA-approved for patients BCG-unresponsive NMIBC. Encouraging clinical trial results for intravesical nadofaragene firadenovec, oportuzumab monatox and ALT-803 + BCG have been released, while data from trials of other treatment strategies, including novel chemotherapy and drug delivery, augmented BCG immunotherapy, adenoviral and gene therapy, targeted therapy, and combination systemic immunotherapy with intravesical agents, are eagerly awaited.
    Summary: Several novel salvage therapies offer promise for patients with BCG-unresponsive NMIBC. Patient selection, efficacy, safety, cost and ease of administration must be carefully considered to determine the optimal treatment approach.
    MeSH term(s) Administration, Intravesical ; BCG Vaccine/adverse effects ; Humans ; Neoplasm Invasiveness ; Neoplasm Recurrence, Local ; Prospective Studies ; Salvage Therapy ; Urinary Bladder Neoplasms/drug therapy
    Chemical Substances BCG Vaccine
    Language English
    Publishing date 2021-03-19
    Publishing country United States
    Document type Journal Article ; Review
    ZDB-ID 1091792-5
    ISSN 1473-6586 ; 0963-0643
    ISSN (online) 1473-6586
    ISSN 0963-0643
    DOI 10.1097/MOU.0000000000000863
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  8. Article: Patient Characteristics and Survival Outcomes of Non-Metastatic, Non-Clear Cell Renal Cell Carcinoma.

    An, Josiah / Packiam, Vignesh T / Chennamadhavuni, Adithya / Richards, Jordan / Jain, Jayanshu / Mott, Sarah L / Garje, Rohan

    Frontiers in oncology

    2022  Volume 11, Page(s) 786307

    Abstract: Background: Non-clear cell renal cell carcinoma (ccRCC) includes histologically and molecularly distinct subtypes such as papillary, chromophobe, collecting duct, and sarcomatoid RCC, with an incidence ranging from 20% to 25%. Oncologic outcomes and the ...

    Abstract Background: Non-clear cell renal cell carcinoma (ccRCC) includes histologically and molecularly distinct subtypes such as papillary, chromophobe, collecting duct, and sarcomatoid RCC, with an incidence ranging from 20% to 25%. Oncologic outcomes and the role of adjuvant systemic therapy [vascular endothelial growth factor inhibitor (VEGFi) or immunotherapy] for non-ccRCC are not well-described.
    Objective: To assess the incidence and survival outcomes of non-ccRCC subtypes in comparison to ccRCC.
    Methods: The National Cancer Database was utilized to identify patients with non-metastatic RCC (T1-T4, N0-N1) between 2004 and 2015. The non-ccRCC cohort was further stratified by histologic subtype: papillary, chromophobe, sarcomatoid, and collecting duct RCC. Multivariable Cox regression models were used to compare overall survival (OS).
    Results: The 5-year OS for chromophobe, papillary, clear cell, collecting duct, and sarcomatoid RCC was 91%, 82%, 81%, 44%, and 40%, respectively. After adjusting for clinicopathologic and treatment characteristics, there was no significant difference in OS between papillary RCC and ccRCC (p = 0.17). Patients with collecting duct and sarcomatoid subtypes were at over two times increased risk of death compared to patients with clear cell (p < 0.01 and p < 0.01, respectively). Conversely, patients with chromophobe RCC were at 36% decreased risk of death compared to ccRCC (p < 0.01).
    Conclusions: This hospital-based analysis confirms that collecting duct and sarcomatoid histologic subtypes are uncommon and associated with poor survival after surgery when compared to the other RCC subtypes. Further studies are needed to evaluate the role of neoadjuvant and adjuvant systemic therapies in these subtypes to improve oncologic outcomes.
    Language English
    Publishing date 2022-01-10
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2649216-7
    ISSN 2234-943X
    ISSN 2234-943X
    DOI 10.3389/fonc.2021.786307
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  9. Article ; Online: Sequential Intravesical Gemcitabine and Docetaxel for bacillus Calmette-Guérin-Naïve High-Risk Nonmuscle-Invasive Bladder Cancer.

    McElree, Ian M / Steinberg, Ryan L / Martin, Alex C / Richards, Jordan / Mott, Sarah L / Gellhaus, Paul T / Nepple, Kenneth G / O'Donnell, Michael A / Packiam, Vignesh T

    The Journal of urology

    2022  Volume 208, Issue 3, Page(s) 589–599

    Abstract: Purpose: Bacillus Calmette-Guérin (BCG) is currently recommended as adjuvant therapy following complete transurethral resection of bladder tumor for high-risk nonmuscle-invasive bladder cancer (NMIBC). In response to the BCG shortage, gemcitabine plus ... ...

    Abstract Purpose: Bacillus Calmette-Guérin (BCG) is currently recommended as adjuvant therapy following complete transurethral resection of bladder tumor for high-risk nonmuscle-invasive bladder cancer (NMIBC). In response to the BCG shortage, gemcitabine plus docetaxel (Gem/Doce) has been utilized at our institution in the BCG-naïve setting. We report the outcomes of patients with high-risk BCG-naïve NMIBC treated with Gem/Doce.
    Materials and methods: We retrospectively reviewed patients with BCG-naïve high-risk NMIBC treated with Gem/Doce from May 2013 through April 2021. Patients received 6 weekly intravesical instillations of sequential 1 gm gemcitabine and 37.5 mg docetaxel after complete transurethral resection of bladder tumor. Monthly maintenance of 2 years was initiated if disease-free at first followup. The primary outcome was recurrence-free survival. Survival was assessed with the Kaplan-Meier method, indexed from the first Gem/Doce instillation. Adverse events were reported using CTCAE (Common Terminology Criteria for Adverse Events) v5 (National Cancer Institute, Bethesda, Maryland). Differences were assessed with the log-rank test.
    Results: There were 107 patients with a median followup of 15 months included in the analysis. Patients had high-risk characteristics including 47 with any carcinoma
    Conclusions: Gem/Doce is an effective and well-tolerated therapy for BCG-naïve NMIBC. Further investigation is warranted.
    MeSH term(s) Adjuvants, Immunologic/therapeutic use ; Administration, Intravesical ; BCG Vaccine/therapeutic use ; Bacillus ; Carcinoma in Situ ; Deoxycytidine/analogs & derivatives ; Docetaxel/therapeutic use ; Humans ; Neoplasm Invasiveness ; Neoplasm Recurrence, Local/pathology ; Retrospective Studies ; Urinary Bladder Neoplasms/pathology
    Chemical Substances Adjuvants, Immunologic ; BCG Vaccine ; Deoxycytidine (0W860991D6) ; Docetaxel (15H5577CQD) ; gemcitabine (B76N6SBZ8R)
    Language English
    Publishing date 2022-07-27
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't
    ZDB-ID 3176-8
    ISSN 1527-3792 ; 0022-5347
    ISSN (online) 1527-3792
    ISSN 0022-5347
    DOI 10.1097/JU.0000000000002740
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Reply by Authors.

    McElree, Ian M / Steinberg, Ryan L / Martin, Alex C / Richards, Jordan / Mott, Sarah L / Gellhaus, Paul T / Nepple, Kenneth G / O'Donnell, Michael A / Packiam, Vignesh T

    The Journal of urology

    2022  Volume 208, Issue 3, Page(s) 599–600

    Language English
    Publishing date 2022-07-27
    Publishing country United States
    Document type Journal Article ; Comment
    ZDB-ID 3176-8
    ISSN 1527-3792 ; 0022-5347
    ISSN (online) 1527-3792
    ISSN 0022-5347
    DOI 10.1097/JU.0000000000002740.04
    Database MEDical Literature Analysis and Retrieval System OnLINE

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