Closed orbit feed-back from low-β\beta quadrupole movements at LEP

Left and right of each of the four LEP interaction points superconducting low-beta quadrupole magnets are installed to squeeze the vertical beam size at the interaction points. These magnets are the dominant source of vertical closed orbit drifts at LEP because of their strength, the large vertical beta function and their support. Hydrostatic Levelling Systems and resistor-based position sensors were installed to measure the vertical movements of these magnets continuously. The correlation between the mechanical movements and closed orbit variations has been studied. The analysis has shown that the orbit can be kept stable by acting on one correction dipole per low-beta quadrupole pair. This has led to a feed-back system which uses the mechanical measurements to correct the closed orbit and to prevent large orbit variations

Multi-state optimal power dispatch model for power-to-power systems in off-grid hybrid energy systems: A case study in Spain

The electricity production from Renewable Energy (RE) in isolated locations requires long-term energy storage systems. To that end, Hybrid Energy Storage Systems (HESS), through a combination of hydrogen and batteries, can benefit from the different advantages of both technologies. This paper presents a hybrid Power-to-Power (PtP) Optimal Power Dispatch (OPD) model for isolated systems with no electric grid access. Currently, the electricity supply in such cases is usually based on a mix of RE as the primary energy source sustained by a diesel genset acting as a backup generator. In this context, the model delivers the hourly energy flows between renewable production sources, energy storage devices and the electrical load, which minimises costs and Green House Gases (GHG) emissions. For validation purposes, the model was tested through its application to a case study in an isolated area in the Canary Islands, Spain. The results show that the algorithm calculates the hourly OPD successfully for a given plant sizing, considering the defined operational states of the different assets. These operational constraints showed a decrease in the PtP round-trip efficiency of 5.4% and a reduction of the hydrogen production of 9.7%. Finally, the techno-economic analysis of the results proves that the combination of hydrogen and batteries with RE production is a feasible alternative to phasing out fossil fuels for the selected case study – reducing the diesel generator usage down to 1.2% of the yearly energy supply

Revisiting Reader Privacy in the Age of the E-Book, 45 J. Marshall L. Rev. 175 (2011)

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Phasing out steam methane reformers with water electrolysis in producing renewable hydrogen and ammonia: A case study based on the Spanish energy markets

Deploying renewable hydrogen presents a significant challenge in accessing off-takers who are willing to make long-term investments. To address this challenge, current projects focus on large-scale deployment to replace the demand for non-renewable hydrogen, particularly in ammonia synthesis for fertiliser production plants. The traditional process, involving Steam Methane Reformers (SMR) connected to Haber-Bosch synthesis, could potentially transition towards decarbonisation by gradually integrating water electrolysis. However, the coexistence of these processes poses limitations in accommodating the integration of renewable hydrogen, thereby creating operational challenges for industrial hubs. To tackle this issue, this paper proposes an optimal dispatch model for producing green hydrogen and ammonia while considering the coexistence of different processes. Furthermore, the objective is to analyse external factors that could determine the appropriate regulatory and pricing framework to facilitate the phase-out of SMR in favour of renewable hydrogen production. The paper presents a case study based in Spain, utilising data from 2018, 2022 and 2030 perspectives on the country's renewable resources, gas and electricity wholesale markets, pricing ranges, and regulatory constraints to validate the model. The findings indicate that carbon emissions taxation and the availability and pricing of Power Purchase Agreements (PPAs) will play crucial roles in this transition - the carbon emission price required for total phasing out SMR with water electrolysis would be around 550 EUR/ton CO2

Opposite macrophage polarization in different subsets of ovarian cancer: observation from a pilot study

The role of the innate immune system in ovarian cancer is gaining importance. The relevance of tumor-associated macrophages (TAM) is insufficiently understood. In this pilot project, comprising the immunofluorescent staining of 30 biopsies taken from 24 patients with ovarian cancer, we evaluated the presence of total TAM (cluster of differentiation (CD) 68 expression), M1 (major histocompatibility complex (MHC) II expression), and M2 (anti-mannose receptor C type 1 (MRC1) expression), and the blood vessel diameter. We observed a high M1/M2 ratio in low-grade ovarian cancer compared to high-grade tumors, more total TAM and M2 in metastatic biopsies, and a further increase in total TAM and M2 at interval debulking, without beneficial effects of bevacizumab. The blood vessel diameter was indicative for M2 tumor infiltration (Spearman correlation coefficient of 0.65). These data mainly reveal an immune beneficial environment in low-grade ovarian cancer in contrast to high-grade serous ovarian cancer, where immune suppression is not altered by neoadjuvant therapy

Determination of the Accuracy of Wire Position Sensors

An energy spectrometer has been installed in the LEP accelerator to determine the beam energy with a relative accuracy of 10-4. A precisely calibrated bending magnet is flanked by 6 beam position monitors (BPM). The beam energy is determined by measuring the deflection angle of the LEP beams and the integrated bending field. An accuracy of less than 10-6 m on the beam position is necessary to reach the desired accuracy on the LEP beam energy. Capacitive wire positioning sensors are used to determine the relative mounting stability of each BPM and to calibrate the beam position monitors. Two-dimensional sensors are attached to each side of every BPM support and provide a position measurement with respect to two stretched wires mounted on either side of the LEP beam pipe. The fixing points of each wire are monitored by additional reference sensors. The position information is digitised via a multiplexed high accuracy digital voltmeter and read out continuously during LEP operations. Wire position sensor accuracy was tested in the laboratory with a laser interferometer, while relative accuracy tests are performed in the LEP environment. Systematic effects of synchrotron radiation on the wire position sensor performance were studied

Early surgical complications after congenital diaphragmatic hernia repair by thoracotomy vs. laparotomy: A bicentric comparison

Purpose: The surgical strategy for congenital diaphragmatic hernia (CDH) repair remains debated and mainly depends on the training and preference of the surgeon. Our aim was to evaluate the occurrence and nature of surgical reinterventions within the first year of life, following repair through thoracotomy as compared to laparotomy. / Methods: This is a retrospective bi-centric cohort study comparing postero-lateral thoracotomy (n = 55) versus subcostal laparotomy (n = 62) for CDH repair (IRB: MP001882). We included neonates with isolated, left-sided, Bochdalek-type CDH who were operated on between 2000 and 2017, and had a minimum follow-up of 1 year. Excluded were patients treated prenatally and/or had extra-corporeal membrane oxygenation. Outcomes were occurrence and nature of surgical reinterventions and mortality by 1 year of life. / Results: Both groups had comparable neonatal severity risk profiles. The overall surgical reintervention rate by 1 year of age was higher in the thoracotomy group (29.1% vs. 6.5%; p = 0.001), mainly because of a higher prevalence of acute bowel complications (18.1% vs. 3.2%; p = 0.012) requiring surgery, such as perforation, obstruction and volvulus. At 1 year of follow-up, groups were similar in terms of recurrence (5.5% vs. 1.6%; p = 0.341), surgical interventions related to severe gastroesophageal reflux disease (3.6% vs. 1.6%; p = 0.600) and mortality (5.5% vs. 6.6%; p = 1.000). / Conclusion: Postnatal CDH repair through thoracotomy was associated with a higher rate of surgical reinterventions within the first year of life, especially for severe acute gastro-intestinal complications. There seemed to be no difference in recurrence and mortality rate. / Type of Study: Retrospective Comparative Cohort Study. / Level of Evidence: Level III

VALIDATION OF ENVISAT-1 LEVEL-2 PRODUCTS RELATED TO LOWER ATMOSPHERE O3 AND NOy CHEMISTRY BY A FTIR QUASI-GLOBAL NETWORK

A coordinated action involving eleven stations of the ground-based Network for Detection of Stratospheric Change (NDSC) equipped with Fourier transform infrared (FTIR) instruments was conducted to contribute to the validation of the three atmospheric chemistry instruments onboard ENVISAT, that are MIPAS, SCIAMACHY and GOMOS. The target products for validation are total columns of O3, CH4, CO and some important NOy species (NO2, HNO3, NO) and the source gas N2O. Together the eleven stations cover the latitudes between 79 °N and 78°S, including polar, mid -latitude and subtropical and tropical locations. The goal is to contribute to the assessment of the data quality of the aforementioned ENVISAT instruments, from a quasi-global perspective. The period of intensive ground-based data collection for the benefit of the ENVISAT Validation Commissioning Phase that is dealt with in the present paper is July 15 to December 1, 2002. The FTIR network involved collected a data set corresponding to an equivalent of approximately 400 days of measurements; about three quarter of the data have already been submitted to the ENVISAT Calval database and are included in the present work. Unfortunately, the distribution of ENVISAT data has been slow and limited. Only a limited number of coincidences has been found for making data inter-comparisons. Therefore, the conclusions drawn in this paper are very preliminary and cover only a limited set of data products from SCIAMACHY only. Our findings up to now concerning the above mentioned target products are the following: (1) SCIAMACHY near infrared operational products (CO, CH4, N2O) have no scientific meaning yet, (2), the operational SCIAMACHY total vertical O3 column product derived in the ultraviolet window has undergone some improvements with changing versions of the processor(s) but it still underestimates the column by about 5 – 10 %, (3), the operational SCIAMACHY total vertical O3 column product derived in the visible window is unrealistically large, and (3), the operational NO2 total column product from SCIAMACHY seems to largely overestimate the real column, but very few coincidences and large dispersions of the data do inhibit any further conclusion at present. In a next phase, the same ground-based correlative data set will be exploited to further validate the ENVISAT data as soon as more and reprocessed data will be distributed