Over de ontzilting van den bodem in de Wieringermeer : een studie over de zout- en waterbeweging in jonge poldergronden

The initial concentration of salt in the soil moisture of the Wieringermeer (reclaimed from the sea in 1930) was about 2 %. The moisture content of the soil and hence the salt content in dry matter increased with increasing clay content.Percolating rainwater attained the concentration of the soil moisture within a depth of 25 to 50 cm. Diffusion hardly influenced salt movement as such, but was highly instrumental in equalizing the salt concentration of the percolating rainwater and of the soil moisture.In comparable leaching conditions the topmost layer of sandy soils was leached faster than of clay soils. For the deeper layers the reverse was true. Usually the low permeability of the clayey subsoils hampered passage of water. In soils with vegetation upward capillary transport did not exceed about 50 mm a year. Seepage retarded desalinization considerably.The better the drainage the faster the leaching. After laying an adequate field- drainage system the rains of one winter leached sufficient salt from sandy soils to allow crop growth; for a comparable leaching of clay soils the rains of two to three winters were required

Pathological response and tumour bed histopathological features correlate with survival following neoadjuvant immunotherapy in stage III melanoma

Background: Guidelines for pathological evaluation of neoadjuvant specimens and pathological response categories have been developed by the International Neoadjuvant Melanoma Consortium (INMC). As part of the Optimal Neo-adjuvant Combination Scheme of Ipilimumab and Nivolumab (OpACIN-neo) clinical trial of neoadjuvant combination anti-programmed cell death protein 1/anti-cytotoxic T-Iymphocyte-associated protein 4 immunotherapy for stage III melanoma, we sought to determine interobserver reproducibility of INMC histopathological assessment principles, identify specific tumour bed histopathological features of immunotherapeutic response that correlated with recurrence and relapse-free survival (RFS) and evaluate proposed INMC pathological response categories for predicting recurrence and RFS.Patients and methods: Clinicopathological characteristics of lymph node dissection specimens of 83 patients enrolled in the OpACIN-neo clinical trial were evaluated. Two methods of assessing histological features of immunotherapeutic response were evaluated: the previously described immune-related pathologic response (irPR) score and our novel immunotherapeutic response score (ITRS). For a subset of cases (n = 29), cellular composition of the tumour bed was analysed by flow cytometry.Results: There was strong interobserver reproducibility in assessment of pathological response (kappa = 0.879) and percentage residual viable melanoma (intraclass correlation coefficient = 0.965). The immunotherapeutic response subtype with high fibrosis had the strongest association with lack of recurrence (P = 0.008) and prolonged RFS (P = 0.019). Amongst patients with criteria for pathological non-response (pNR, >50% viable tumour), all who recurred had >= 70% viable melanoma. Higher ITRS and irPR scores correlated with lack of recurrence in the entire cohort (P = 0.002 and P = 70% viable melanoma and incorporating additional criteria of <10% fibrosis subtype of response may identify those at highest risk of recurrence, but requires validation.Analysis and support of clinical decision makin

Survival and biomarker analyses from the OpACIN-neo and OpACIN neoadjuvant immunotherapy trials in stage III melanoma

Neoadjuvant ipilimumab plus nivolumab showed high pathologic response rates (pRRs) in patients with macroscopic stage III melanoma in the phase 1b OpACIN () and phase 2 OpACIN-neo () studies(1,2). While the results are promising, data on the durability of these pathologic responses and baseline biomarkers for response and survival were lacking. After a median follow-up of 4 years, none of the patients with a pathologic response (n = 7/9 patients) in the OpACIN study had relapsed. In OpACIN-neo (n = 86), the 2-year estimated relapse-free survival was 84% for all patients, 97% for patients achieving a pathologic response and 36% for nonresponders (P < 0.001). High tumor mutational burden (TMB) and high interferon-gamma-related gene expression signature score (IFN-gamma score) were associated with pathologic response and low risk of relapse; pRR was 100% in patients with high IFN-gamma score/high TMB; patients with high IFN-gamma score/low TMB or low IFN-gamma score/high TMB had pRRs of 91% and 88%; while patients with low IFN-gamma score/low TMB had a pRR of only 39%. These data demonstrate long-term benefit in patients with a pathologic response and show the predictive potential of TMB and IFN-gamma score. Our findings provide a strong rationale for a randomized phase 3 study comparing neoadjuvant ipilimumab plus nivolumab versus standard adjuvant therapy with antibodies against the programmed cell death protein-1 (anti-PD-1) in macroscopic stage III melanoma

Seasonal development of a deep pelagic bioluminescent layer in the temperate NE Atlantic Ocean

ABSTRACT: Vertical distribution of bioluminescent organisms throughout the water column in the Porcupine Seabight and Porcupine Abyssal plain area of the NE Atlantic Ocean was measured using a free-falling autonomous vehicle equipped with a high-sensitivity video system viewing stimulated flashes of light from impacts on a mesh screen. Data were recorded from 500 m depth down to the sea floor at depths from 740 to 4808 m during spring and autumn of 2001 and 2002. Bioluminescent organisms decreased in abundance from a maximum of 80 m–3 at 600 m depth to a mean of 0.5 to 1.2 m–3 at depths greater than 3000 m. During autumn, a seasonally enhanced peak of abundance (mean 27.19 m–3, compared with 7.52 m–3 in spring) centred at 1420 m within the depth range of occurrence of Mediterranean intermediate water. It is hypothesised that this bioluminescent layer reflects seasonal increase in deep pelagic biomass fed by downward transport of organic matter following the spring peak of primary production in the surface layers. The bioluminescent layer is a large-scale regional phenomenon extending over 100s of kilometres

Risk factors for hearing loss in patients treated with intensity-modulated radiotherapy for head-and-neck tumors

Purpose: Radiotherapy (RT) is a common treatment of head-and-neck carcinoma. The objective of this study was to perform a prospective multivariate assessment of the dose-effect relationship between intensity-modulated RT and hearing loss. Methods and Materials: Pure tone audiometry at 0.250-16 kHz was obtained before and after treatment in 101 patients (202 ears). All Patients received full-course intensity-modulated RT (range, 56-70 Gy), with a median cochlear dose of 11.4 Gy (range, 0.2-69.7). Results: Audiometry was performed 1 week before and a median of 9 weeks (range, 1-112) after treatment. The mean hearing deterioration at pure tone average air-conduction 1-2-4 kHz was small (from 28.6 dB HL to 30.1 dB HL). However, individual patients showed clinically significant hearing loss, with 10-dB threshold shift incidences of 13% and 18% at pure tone averages air-conduction 1-2-4 kHz and 8-10-12.5 kHz, respectively. Post-treatment hearing capability was unfavorable in the case of greater inner ear radiation doses (p <0.0001), unfavorable baseline hearing capability (p <0.0001), green-eyed patients (p <0.0001), and older age (p <0.0001). Using multivariate analysis, a prediction of individual hearing capabiltity after treatment was made. Conclusion: RT-induced hearing loss in the mean population is modest. However, clinically significant hearing loss was observed in older patients with green eyes and unfavorable pretreatment hearing. In these patients, the intended radiation dose may be adjusted according to the proposed predictive model, aiming to decrease the risk of ototoxicity. Crown Copyright (C) 2009 Published by Elsevier In

A hybrid registration method using the mandibular bone surface for electromagnetic navigation in mandibular surgery

Purpose To utilize navigated mandibular (reconstructive) surgery, accurate registration of the preoperative CT scan with the actual patient in the operating room (OR) is required. In this phantom study, the feasibility of a noninvasive hybrid registration method is assessed. This method consists of a point registration with anatomic landmarks for initialization and a surface registration using the bare mandibular bone surface for optimization. Methods Three mandible phantoms with reference notches on two osteotomy planes were 3D printed. An electromagnetic tracking system in combination with 3D Slicer software was used for navigation. Different configurations, i.e., different surface point areas and number and configuration of surface points, were tested with a dentate phantom (A) in a metal-free environment. To simulate the intraoperative environment and different anatomies, the registration procedure was also performed with an OR bed using the dentate phantom and two (partially) edentulous phantoms with atypical anatomy (B and C). The accuracy of the registration was calculated using the notches on the osteotomy planes and was expressed as the target registration error (TRE). TRE values of less than 2.0 mm were considered as clinically acceptable. Results In all experiments, the mean TRE was less than 2.0 mm. No differences were found using different surface point areas or number or configurations of surface points. Registration accuracy in the simulated intraoperative setting was-mean (SD)-0.96 (0.22), 0.93 (0.26), and 1.50 (0.28) mm for phantom A, phantom B, and phantom C. Conclusion Hybrid registration is a noninvasive method that requires only a small area of the bare mandibular bone surface to obtain high accuracy in phantom setting. Future studies should test this method in clinical setting during actual surgery

Total laryngectomy for a dysfunctional larynx after (chemo)radiotherapy

Objective To evaluate the functional outcomes after total laryngectomy (TLE) for a dysfunctional larynx in patients with head and neck cancer that is in complete remission after (chemo)radiotherapy. Design Retrospective cohort study. Setting Tertiary comprehensive cancer center. Patients The study included 25 patients from a cohort of 217 consecutive patients with TLE who were treated between January 2000 and July 2010. The inclusion criteria for this subgroup analysis were complete remission and functional problems for which TLE was considered to be the only resolution. Quality of life assessment was carried out using the European Organization for Research and Treatment of Cancer Quality of Life C30 and Head and Neck Module 35 questionnaires and an additional study-specific questionnaire covering functional aspects, such as swallowing and dyspnea, in more detail. Intervention Total laryngectomy. Main Outcome Measures Morbidity, mortality, and functional outcomes. Results The indication for TLE was chronic aspiration with or without recurrent pneumonia (n = 15 [60%]), debilitating dyspnea (n = 8 [32%]), and persistent profuse hemorrhage (radiation ulcer) (n = 2 [8%]). After TLE, 14 of the 25 patients (56%) had 20 major postoperative complications, including 11 pharyngocutaneous fistulas, requiring additional treatment. Tube feeding and recurrent pneumonia incidence had decreased from 80% and 28% to 29% and 0%, respectively, 2 years after surgery. Prosthetic voice rehabilitation was possible in 19 patients (76%). Two years after surgery, 10 of 14 patients (71%) still reported TLE-related pulmonary problems despite the consistent use of a heat and moisture exchanger. The 5-year overall survival rate was 35%. Conclusions Total laryngectomy for a dysfunctional larynx tends to have a high complication rate. However, in this study, the initial functional problems (aspiration, recurrent pneumonia, and dyspnea) did not recur. Tube feeding was significantly reduced, and the quality of life of the surviving patients appeared to be reasonable

Registration methods for surgical navigation of the mandible: a systematic review

Image-to-patient registration in navigated mandibular surgery is complex due to the mobile nature of the mandible compared with other craniofacial bones. As a result, surgical navigation is rarely employed in the mandibular region. This systematic review provides an overview of the different registration methods that are used for surgical navigation of the mandible. A systematic search was performed in the MEDLINE Ovid, Scopus, and Embase databases on March 25, 2021. Search terms included synonyms for mandibular surgery, surgical navigation, and registration methods. Articles about navigated mandibular surgery, where the registration method was explicitly mentioned, were included. The database search yielded a total of 2952 articles, from which 81 articles remained for analysis. Four main registration methods were identified: point registration, surface registration, hybrid registration, and computer vision-based registration. The mobility of the mandible is accounted for by either keeping the mandible in a fixed position during preoperative imaging and surgery, or by tracking the mandibular movements. Although different registration methods are available for navigated mandibular surgery, there is always a trade-off between accuracy, registration time, usability, and invasiveness. Future studies should focus on testing the different methods in larger patient studies and should report the registration accuracy