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Geoscientific models are simplified representations of complex earth and environmental systems (EESs). Compared with physics-based numerical models, data-driven modeling has gained popularity due mainly to data proliferation in EESs and the ability to perform prediction without requiring explicit mathematical representation of complex biophysical processes. However, because of the black-box nature of data-driven models, their performance cannot be guaranteed. To address this issue, we developed a generalizable framework for improving the efficiency and effectiveness of model training and the reduction of model overfitting. This framework consists of two parts: hyperparameter selection based on Sobol global sensitivity analysis and hyperparameter tuning using a Bayesian optimization approach. We demonstrated the framework efficacy through a case study of daily edge-of-field (EOF) runoff predictions by a tree-based data-driven model using the extreme gradient boosting (XGBoost) algorithm in the Maumee domain, USA. This framework contributes towards improving the performance of a variety of data-driven models and can thus help promote their applications in EESs.

Geoscientific models are simplified representations of complex earth and environmental systems (EESs). Compared with physics-based numerical models, data-driven modeling has gained popularity due mainly to data proliferation in EESs and the ability to perform prediction without requiring explicit mathematical representation of complex biophysical processes. However, because of the black-box nature of data-driven models, their performance cannot be guaranteed. To address this issue, we developed a generalizable framework for the improvement of the efficiency and effectiveness of model training and the reduction of model overfitting. This framework consists of two parts: hyperparameter selection based on Sobol global sensitivity analysis, and hyperparameter tuning using a Bayesian optimization approach. We demonstrated the framework efficacy through a case study of daily edge-of-field (EOF) runoff predictions by a tree-based data-driven model using eXtreme Gradient Boosting (XGBoost) algorithm in the Maumee domain, U.S. This framework contributes towards improving the performance of a variety of data-driven models and can thus help promote their applications in EESs.

Objectives To determine the relative effectiveness of this holistic approach on metastatic cancer, breast (BC), genitourinary (GU), gynecologic (GYN), and lung (LC) cancer survival rates were compared to those from a similar oncology study investigating the impact of patient symptom reporting. As a secondary outcome, survival for BC, GU, GYN, LC, pancreatic (PC), and colon (CC) cancer patients from one through five years after metastatic cancer diagnosis was compared to normative data from the Surveillance, Epidemiology, and End Results Program (SEER) database. Methods Survival for breast, genitourinary, gynecologic, and lung cancers at one through five years was compared to (1) similar data from an electronic symptom self-reporting study; and (2) normative data from the Surveillance, Epidemiology, and End Results Program (SEER) using estimated survival curves and 95 % confidence intervals. Results Charts for 104 patients with metastatic breast, genitourinary (bladder and kidney), gynecologic (endometrial and ovarian), lung (non-small cell), pancreatic, and colon cancers were analyzed, and survival calculated. When analyzing only breast, genitourinary, gynecologic, and lung cancers to rates from the comparable study, the clinic’s one-year survival was significantly higher than with the comparable data (80.8 % vs. 75.1 % respectively) evidenced by 95 % confidence intervals. Comparison of the current population data (including all cancer types) and normative SEER data rendered statistically significant results for survival at 1, 2, 3, 4, and 5 years, evidenced by 95 % confidence intervals. Conclusions The clinic data showed survival that was higher than the computerized symptom monitoring arm of current reported research. Additionally, it was further increased when compared to normative SEER data. This suggested that results produced by electronic platforms used in large academic settings can be successfully reproduced by community oncology practices through non-electronic approaches to active symptom management and shared decision-making.

Purpose A critical component of breast cancer (BC) chemotherapy effectiveness is relative dose intensity (RDI), as Methods The medical records of 161 BC patients (M = 61.5 years, SD = 12.7) from a holistic cancer clinic were collected and analyzed. This clinic offers a patient-centered approach (i.e., patients actively make decisions, treatment education, chair yoga, reiki, and nutritional counseling). RDI was determined by calculating the ratio of the received dose versus the intended dose intensity. Results 92% of patients had an RDI ≥ 85% (Mean = 96%) and 8 of the 9 treatment regimens' RDI exceeded 85%. RDI had a significant positive association with BMI (p = .06), and being ER+ and/or HER2+ (p’s = .08). None of the remaining demographic or clinical characteristics were associated. Conclusions This non-pharmacologic approach led to a higher RDI than recommended, potentially improving BC patients’ prognosis. Higher RDI was related to BMI, and ER+ and HER2 status. Additional research is needed; however, these results provide promising evidence regarding the benefits of a patient-centered, holistic approach.

The relevance of Brushless DC motors has been increasing across industries and industrial applications for a multitude of advantages. This paper concerns the implementation of the brushless DC motor in the buck-boost, Cuk and Sheppard-Taylor topologies. Duty ratio of the pulse signal sent to the power MOSFET has been varied for buck and boost operation and subsequently motor parameters across the three separate establishments have been compared. Design and simulation of the converter circuits have been done using MATLAB/Simulink. The motor parameters under discussion are stator back emf, rotor speed and electromagnetic torque. A conscious effort has been made to present the parameter values in an easily comparable manner for the three topologies. Finally, a conclusion has been drawn on the best possible topology among the three to enable the motor to function efficiently and help us get desirable results when the motor is in operation.

We showed in a phase I trial that the maximum tolerated dose of the ProMACE-CytaBOM regimen in patients with aggressive lymphoma was 200% (Gordon et al, J Clin Oncol 14:1275, 1996). Based on these observations, we initiated a phase II trial designed to determine response, toxicity, and dose intensity using this regimen. We analyzed 74 patients with advanced-stage (III or IV) or bulky stage II aggressive lymphoma. The overall complete response rate was 69% (72% in evaluable patients). With a median follow-up of 4.5 years, the median survival has not yet been reached. The 4-year survival rate is 73% (95% confidence interval [CI] 62, 83%) and no difference was observed among International Prognostic Index (IPI) groups. The 4-year disease-free survival was 71% (95% CI 58, 84%) with no statistical difference between patients with IPI 0 to 1 versus 2 to 4. The toxicity was acceptable, though the grade 4 hematologic toxicity rate for this regimen was 100%. Grade 4 nonhematologic toxicity was 36%. Three cases of either myelodysplastic syndrome or acute leukemia occurred at 7 months, 3.4 years, and 4.2 years after registration. Cytogenic analysis was available in two cases, showing inv(16) without French American British classification (FAB) M4 EO histology in one patient and a 5q-syndrome in the other. These data suggest that 200% ProMACE-CytaBOM with either granulocyte-macrophage colony-stimulating factor (GM-CSF) or G-CSF results in a high complete remission rate and a disease-free survival comparable to any prior risk-based analysis in aggressive lymphoma. Before using this regimen in general practice, phase III clinical trials should be conducted.

PURPOSE A minority of cancer survivors develops long-term postsurgical neuropathic pain. Based on evidence that capsaicin, the pungent ingredient in hot chili peppers, might be useful for treating neuropathic pain, we developed the present clinical trial. PATIENTS AND METHODS Ninety-nine assessable patients with postsurgical neuropathic pain were entered onto this study. After stratification, patients were to receive 8 weeks of a 0.075% capsaicin cream followed by 8 weeks of an identical-appearing placebo cream, or vice versa. A capsaicin/placebo cream was to be applied to the painful site four times daily. Treatment evaluation was performed by patient-completed weekly questionnaires. RESULTS During the first 8-week study period, the capsaicin-cream arm was associated with substantially more skin burning, skin redness, and coughing (P < .0001 for each). Nonetheless, treatment was stopped for patient refusal or toxicity just as often while patients were receiving the placebo as compared with the capsaicin. The capsaicin cream arm had substantially more pain relief (P = .01) after the first 8 weeks, with an average pain reduction of 53% versus 17%. On completion of the 16-week study period, patients were asked which treatment period was most beneficial. Of the responding patients, 60% chose the capsaicin arm, 18% chose the placebo arm, and 22% chose neither (P = .001). CONCLUSION A topical capsaicin cream decreases postsurgical neuropathic pain and, despite some toxicities, is preferred by patients over a placebo by a three-to-one margin among those expressing a preference.

PURPOSE To evaluate the objective tumor response rate and toxicities of patients with metastatic colorectal carcinoma treated with irinotecan hydrochloride (CPT-11). PATIENTS AND METHODS A total of 121 patients with advanced colorectal carcinoma--90 with prior fluorouracil (5-FU) exposure and 31 chemotherapeutically naive patients--were enrolled between May 1993 and June 1994. Patients were treated with CPT-11 at 125 mg/m2 intravenously weekly for 4 weeks followed by a 2-week rest. RESULTS Among 90 patients with prior 5-FU chemotherapy, 12 partial responses were observed (response rate, 13.3%; 95% confidence interval [CI], 7.1% to 22.1%). Among 31 chemotherapy-naive patients, eight had partial responses (response rate, 25.8%; 95% CI, 11.9% to 44.6%). The median response duration as measured from time of initial treatment for the two groups was 7.7 months and 7.6 months, respectively. The major adverse reactions were gastrointestinal and hematologic. The incidence of grade 3 or 4 diarrhea was 36.4%, while the overall incidence of grade 3 or 4 leukopenia was 21.5% of patients. Only four of 121 patients (3.3%) developed neutropenic fever (grade 4 neutropenia with > or = grade 2 fever). The incidence of grade 4 leukopenia was higher in patients with prior pelvic radiotherapy (chi2 test P = .04), while the incidence of grade 3 or 4 diarrhea demonstrated no association with previous pelvic irradiation. CONCLUSION According to the study design, CPT-11 showed promising activity in chemotherapy-naive patients with advanced colorectal carcinoma and modest activity in patients with prior 5-FU exposure. The toxicity with this schedule appears manageable with appropriate dose modification for individual patient tolerance and an intensive loperamide regimen for the management of diarrhea. Care should be taken when treating patients with prior pelvic radiotherapy because of the increased risk of neutropenia.

PURPOSE Stomatitis is a major dose-limiting toxicity of bolus fluorouracil (5FU)-based chemotherapy regimens, despite the use of oral cryotherapy. Pursuant to preliminary data that suggested a sucralfate oral solution could alleviate chemotherapy-induced oral mucositis, we developed a prospective trial to test this contention. PATIENTS AND METHODS A phase III, double-blind, placebo-controlled clinical trial was designed. Patients were entered onto the study at the time of the first cycle of 5FU-based chemotherapy. All patients received oral cryotherapy for 30 minutes with each dose of 5FU. In addition, each patient was randomized to receive either a sucralfate solution or a placebo solution to be used if they developed mouth tenderness or mouth sores. The study solution was to be used four times daily for 7 days starting on the first day of mouth tenderness or mouth sores. Stomatitis scores were determined by health care providers and by patients themselves. RESULTS There was a total of 131 assessable patients entered onto this trial, 50 of whom developed mucositis and used the study medication (27 sucralfate and 23 placebo). There was no suggestion of any difference in stomatitis severity or duration on either protocol arm. CONCLUSION The resultant data from this clinical trial did not support the prestudy hypothesis that sucralfate would be beneficial for the treatment of 5FU-induced stomatitis.

PURPOSE Megestrol acetate has been reported to improve appetite and quality of life and to decrease nausea and vomiting in patients with cancer anorexia/cachexia. The present trial was formulated to evaluate the impact of megestrol acetate on quality of life, toxicity, response, and survival in individuals with extensive-stage small-cell lung cancer who received concomitant chemotherapy. PATIENTS AND METHODS Patients were randomized to receive megestrol acetate 800 mg/d orally or placebo. In addition, all patients were scheduled to receive a maximum of four cycles of cisplatin and etoposide chemotherapy. Quality of life was self-assessed at entry onto study, with every cycle of chemotherapy, and 4 months thereafter with a linear visual analog scale. Toxicity was evaluated by patient questionnaire and investigator reports. RESULTS A total of 243 eligible patients were randomized. Those who received megestrol acetate had increased nonfluid weight gain (P = .004) and significantly less nausea (P = .0002) and vomiting (P = .02). Significant thromboembolic phenomena occurred more often in patients who received megestrol acetate versus placebo (9% v 2%, P = .01). Patients who received megestrol acetate had more edema (30% v 20%, P = .002), an inferior response rate to chemotherapy (68% v 80%, P = .03), and a trend for inferior survival duration (median, 8.2 v 10.0 months, P = .49). These findings may have been influenced by a poorer quality of life of the megestrol acetate group at study initiation. There were no significant changes in quality of life scores over time between either of the study arms. CONCLUSION Megestrol acetate cannot be routinely recommended for all patients with small-cell lung cancer at the time of chemotherapy initiation. Rather, its therapeutic ratio may be more favorable for patients with problematic cancer anorexia/cachexia.

Background. This clinical trial was developed to determine whether ocular ice pack therapy would decrease 5-fluorouracil(5-FU)-induced ocular toxicity. Methods. Sixty-two patients who suffered from 5-FU-induced ocular toxicity, and were scheduled to receive another cycle of the chemotherapy that caused the ocular toxicity, were entered in this clinical trial. A randomized, crossover design was used, with patients documenting their ocular toxicity by the use of daily diaries. Results. The results from the first cycle of treatment suggested that ocular ice pack therapy decreased 5-FU-induced ocular toxicity ( P = 0.056). The 38 evaluable patients in the crossover analyses demonstrated decreased ocular toxicity with ocular ice pack therapy (p = .001). The ocular ice pack therapy was well tolerated by most of the study participants. Conclusion. Ocular ice pack therapy appears to lessen 5-FU-induced ocular toxicity to a clinically moderate degree. Better methods for decreasing 5-FU-induced ocular toxicity are necessary.

PURPOSE Hydrazine sulfate, an agent that appears to inhibit gluconeogenesis, has been studied in cancer patients for approximately 20 years. There was a recent resurgence of interest in this drug when subset analysis of a small placebo-controlled, double-blind, clinical trial reported improved survival among non-small-cell lung cancer patients with a good performance status who were randomized to receive this drug along with standard chemotherapy. PATIENTS AND METHODS Patients on this trial had newly diagnosed, unresectable non-small-cell lung cancer and were treated with cisplatin and etoposide. In addition, they were randomized to receive hydrazine sulfate or placebo in a double-blind manner. RESULTS A total of 243 patients were randomized. Response rates were similar in the two treatment arms. There were trends for worse time to progression and survival in the hydrazine sulfate arm. No significant differences were noted in the two study arms with regard to toxicity or quality of life (QL). CONCLUSION This trial failed to demonstrate any benefit for patients who received hydrazine sulfate.

The authors conducted a phase II study of somatostatin analogue in 18 patients with extensive stage small cell lung cancer (four with previous treatment, 14 without previous treatment). Patients received 2,000 mg subcutaneously thrice daily. They were required to have an Eastern Cooperative Oncology Group performance score of 0-2 and acceptable pretreatment biochemical parameters. No patient responded to treatment. The median time to progression was 44 days. The median survival was 106 days. Toxicity related to treatment consisted of mild diarrhea and anorexia. Somatostatin analogue is not active as a single agent in the treatment of extensive-stage small cell lung cancer.

At present there remains a need for more effective systemic therapy in advanced pancreatic cancer. Some studies have suggested that infusional chemotherapy schedules and biomodulation of 5-fluorouracil (5-FU) may improve the therapeutic outcome in advanced colon cancer. One such regimen that uses continuous infusion 5-FU, weekly leucovorin, daily dipyridamole, and intermittent mitomycin-C has activity in both colon and unresectable pancreatic carcinoma. The intent of this trial was to test the effectiveness of this four-drug regimen in advanced pancreatic cancer. Patients received 5-FU 200 mg/m2 daily by continuous infusion, leucovorin 30 mg/m2 IV weekly, mitomycin-C 10 mg/m2 day 1, and dipyridamole 75 mg orally four times daily for 5 weeks. After a 1-week break, treatment cycles were repeated every 6 weeks. Eligibility included biopsy-proven advanced measurable pancreatic cancer, Eastern Cooperative Oncology Group performance status 0 and 2, and no prior systemic chemotherapy. Of 46 evaluable patients, 9 partial responses and 1 complete tumor response were seen, for an overall response rate of 22% (95% confidence interval 11-36%). The median survival in the group of 50 patients registered to this trial was 4.6 months, with a range of 0.33 to 40.2 months. Toxicity was manageable, with the most common toxicities (or =grade III National Cancer Institute Common Toxicity Criteria) being anorexia (13%), stomatitis (17%), and hand-foot syndrome (13%). Of note, little severe hematologic toxicity and no significant headaches were reported. Although some patients did respond, the therapeutic results are not encouraging enough to take this regimen to phase III testing.

A 40-year-old woman presented with facial swelling and pressure sensation of the ears and sinuses. Chest roentgenography revealed a right paratracheal mass, which was confirmed by a venogram, and transjugular biopsy showed low-grade leiomyosarcoma. The superior vena cava was resected and reconstructed using a spiral vein graft. Pathologic evaluation revealed a low-grade leiomyosarcoma arising from both the superior vena cava and the azygos vein with clear margins.

PURPOSE Based on evidence that suggests pentoxifylline can inhibit tumor necrosis factor, we set out to evaluate the activity and toxicity of this drug in patients with cancer-associated anorexia and/or cachexia. PATIENTS AND METHODS Seventy patients with an Eastern Cooperative Oncology Group (ECOG) performance status of 0 to 2 with cancer anorexia and/or cachexia (defined by a weight loss of > or = 5 lb in the preceding 2 months or a caloric intake < 20 kcal/kg/d) were stratified and then randomly assigned to receive pentoxifylline or identical-appearing placebo tablets in a double-blind fashion. Patients' weights were monitored and patient questionnaires were used to assess appetite, toxicity, and perception of benefit. RESULTS Pentoxifylline failed to improve the appetites of study patients. Pentoxifylline did not appear to cause any toxicity. CONCLUSION This study failed to demonstrate any benefit of pentoxifylline at this dose and schedule as therapy for cancer anorexia and/or cachexia.