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This paper is devoted to the study of the most suitable protocols needed to verify the lightning protection and ground resistance quality in a large-scale scientific facility located on a site with high risk of lightning strikes. We illustrate this work by reviewing a case study: the largest telescopes of the Northern Hemisphere Cherenkov Telescope Array, CTA-N. This array hosts sensitive and high-speed optoelectronics instrumentation and sits on a clear, free from obstacle terrain at around 2400 m above sea level. The site offers a top-quality sky but also features challenging conditions for a lightning protection system: the terrain is volcanic and has electrical resistivities well above 1 kOhm·m. In addition, the environment often exhibits humidities well below 5%, and strong winds pose challenging conditions. On the other hand, the high complexity of a Cherenkov telescope structure does not allow a straightforward application of lightning protection standards. We describe here how the risk assessment of direct strike impacts was made and how contact voltages and ground system were both tested. Finite Element Simulation (COMSOL Multiphysics) has been used to estimate the current flowing through the parts of the earthing system designed for the telescopes in the case of a direct strike impact. This work is intended to provide assistance to scientists and managers involved in the construction of scientific installations, particularly those in charge of defining verifiable reliability and safety requirements for lightning protection.

Large-scale astrophysical facilities have become increasingly relevant in certain key areas of scientific research but typically require strong financial investments. It is, therefore, crucial to gain a deep understanding of what could be a foreseeable lifespan of a given instrument before providing the required fund to build it. In this paper, we intend to contribute to this understanding with a study of the lifespan of past, current and future observatories and telescopes. The methodology has been based on the compilation of relevant data from twenty telescopes, three of them mounted on space satellites and the other seventeen distributed worldwide. An analysis of the main limiting factors that affect the lifetime of an astrophysical facility is also presented.

The integrated management of water resources is a requirement for environmental preservation and economic development, with the removal of nutrients being one of the main drawbacks. In this work, the efficiency of a bacterial consortium (Ecobacter WP) made up of eight bacterial strains of the genus Bacillus subtilis, Bacillus licheniformis, Bacillus megaterium, Bacillus cereus, Arthrobacter sp., Acinetobacter paraffineus, Corynebacterium sp., and Streptomyces globisporus was evaluated in the removal of nitrogen compounds in domestic wastewater in a plug flow system, in the extended aeration and bioaugmentation (FLAEBI). To promote the nitrification and denitrification processes, three doses were tested to establish the optimal concentration of the bacterial consortium on a laboratory scale and its subsequent application in an outdoor wastewater treatment plant (WWTP). The evaluation period was 15 days for each treatment in the laboratory and WWTP. The parameters monitored both at laboratory and outdoor were pH, temperature, dissolved oxygen, chemical oxygen demand (COD), biochemical oxygen demand (BOD5), ammonium, nitrites, and nitrates. The results indicated that the optimal concentration of the consortium was 30 mg L−1, with a removal of 92% of nitrate at the laboratory and 62% outdoor. Such a difference is attributed to the different operation residence times and the volume that caused different concentration gradients. The consortium studied can be used to promote nitrification and denitrification processes that intervene in the removal of nitrogenous compounds in plants with similar operating conditions, without investment in restructuring or design modification of the WWTP. Graphical abstract

The Large-Sized Telescope (LST) prototype of the future Cherenkov Telescope Array (CTA) is located at the Northern site of CTA, on the Canary Island of La Palma. It is designed to provide optimal performance in the lowest part of the energy range covered by CTA, observing gamma rays down to energies of tens of GeV. The LST prototype started performing astronomical observations in November 2019 during the commissioning of the telescope and it has been taking data since then. In this contribution, we will present the tuning of the characteristics of the telescope in the Monte Carlo (MC) simulations to describe the data obtained, the estimation of its angular and energy resolution, and an evaluation of its sensitivity, both with simulations and with observations of the Crab Nebula.

Silicon photomultipliers (SiPMs) have become the baseline choice for cameras of the small-sized telescopes (SSTs) of the Cherenkov Telescope Array (CTA). On the other hand, SiPMs are relatively new to the field and covering large surfaces and operating at high data rates still are challenges to outperform photomultipliers (PMTs). The higher sensitivity in the near infra-red and longer signals compared to PMTs result in higher night sky background rate for SiPMs. However, the robustness of the SiPMs represents a unique opportunity to ensure long-term operation with low maintenance and better duty cycle than PMTs. The proposed camera for large size telescopes will feature 0.05 degree pixels, low power and fast front-end electronics and a fully digital readout. In this work, we present the status of dedicated simulations and data analysis for the performance estimation. The design features and the different strategies identified, so far, to tackle the demanding requirements and the improved performance are described.

Background The Clinical and Laboratory Standards Institute (CLSI) revised the carbapenem breakpoints for Enterobacteriaceae in 2010. The number of hospitals that adopted revised breakpoints and the clinical impact of delayed adoption has not been explored. Methods We performed a cross-sectional, voluntary survey of microbiology laboratories from California acute care hospitals and long-term acute care hospitals (LTAC) to determine use of revised CLSI breakpoints. Carbapenem-resistant Enterobacteriaceae (CRE) clinical isolates from a single tertiary-care hospital from 2013 to 2017 were examined. All isolates with an elevated minimum inhibitory concentration (MIC; ≥2 µg/mL) to imipenem or meropenem were tested for the presence of carbapenemase genes by polymerase chain reaction (PCR). Results We received responses from 128 laboratories that serve 264/393 (67%) of hospitals and LTACs. Current CLSI carbapenem breakpoints for Enterobacteriaceae were used by 92/128 (72%) laboratories. Among laboratories that used current breakpoints, time to implementation varied from 0 to 68 months (mean, 41 months; median, 55 months). Application of historical breakpoints to isolates with a carbapenemase gene detected by PCR resulted in susceptibility rates of 8.9%, 18.6%, and 18.6% to ertapenem, imipenem, and meropenem, respectively. By current breakpoints

Background Effective measures exist to prevent health care–associated hepatitis B virus (HBV) transmission, yet outbreaks continue to occur. In 2008, the Los Angeles County Department of Public Health identified an outbreak of HBV infections among psychiatric long-term care facility residents. Methods Residents underwent HBV serologic testing and were classified as acutely infected, chronically infected, susceptible, or immune. Persons residing in the facility during 2008 were enrolled in a retrospective cohort study to identify risk factors for acute HBV infection. We assessed infection control practices at the facility. Results Nine of 81 residents (11%) enrolled in the cohort study had acute HBV infection. Five of 15 residents (33%) undergoing podiatric care on a single day subsequently developed acute infection (rate ratio, 4.33; 95% confidence interval, 1.18-15.92). Infection control observations of the consulting podiatrist revealed opportunities for cross-contamination of instruments with blood. Other potential health care and behavioral modes of transmission were identified as well. Residents were offered HBV vaccination, and infection control recommendations were implemented by the podiatrist and facility. Conclusions Of the multiple potential transmission modes identified, exposure to HBV during podiatry was likely the dominant mode in this outbreak. Long-term care facilities should ensure compliance with infection control standards among staff and consulting health care providers.

Pending California legislation prompted an on-line survey of methicillin-resistant Staphylococcus aureus (MRSA) active surveillance practices administered to infection preventionists of all 102 acute care licensed hospitals in Los Angeles County. We describe reported surveillance methods. Ninety-six hospitals responded with 41% performing MRSA active surveillance. Comments indicated resistance to implementation of active surveillance because its benefits remain controversial.

PurposeThe purpose of this paper is to contribute to the analysis of firms’ innovative activities from the knowledge‐intensive service activities (KISA) point of view and analyse their relation to the firms’ competitive performance in the case of a mature industry, the Spanish ceramic tile cluster.Design/methodology/approachThe research is based on a field survey. Through a selection of variables multivariable tests were applied to map the industry from the KISA standpoint and evaluate the impact of certain knowledge intensive service activities on innovation and performance.FindingsInternal and external knowledge‐intensive service activities were related to their output in terms of innovation, competitive advantages and economic performance.Research limitations/implicationsFurther research must consider and segment customers, suppliers, and other firms in the industry as other sources of KIBS.Practical implicationsUnderstanding how firms access and employ the variety of innovation‐related KISA available to them in different industries, and at different times, will help policy makers to design targeted policies and programs to actively stimulate innovation across them. For firms, KISA offers a strategic choice in their innovation objectives.Originality/valueThe present analysis contribution to KISA validates a mathematical model to simulate the relation between KISA and the competitive advantage of the firm in the case of a mature medium‐tech industry.

Studying Those Who Study Us: An Anthropologist in the World of Artificial Intelligence. Diana E. Forsythe. Edited with an Introduction by David Hess. Palo Alto: Stanford University Press,2001. Weaving Work and Motherhood. Anita Ilta Garey. Philadelphia: Temple University Press, 1999. Who Supports the Family? Gender and Breadwinning in Dual–Earner Marriages. Jean L. Potuchek. Stanford, CA: Stanford University Press, 1997. Learning from Saturn: Possibilities for Corporate Governance and Employee Relations. Saul A. Rubenstein and Thomas A. Kochan. Ithaca: Cornell University Press, 2001.

Background Early appropriate antibiotic selection is life saving in sepsis. Facility-level antibiograms inform antibiotic selection after pathogen identification and before susceptibility results are available, but only if ≥ 30 isolates from a given species are tested in the prior year. Stenotrophomonas maltophilia (SM) has a complex resistance profile and is associated with an 8-fold mortality increase. We hypothesized that a regional antibiogram may help inform clinical decision-making for severe SM infections. Methods To generate a regional SM antibiogram, we conducted a cross-sectional, voluntary survey of 2015 cumulative facility-level antibiograms from all hospitals in LA county. Non-respondents were contacted to improve response rates. Isolates from sterile sources were pooled. Susceptibility was aggregated and percent susceptible was calculated only when all isolates were tested, i.e. not reflex testing. To identify optimal combination empiric therapy for SM infections, we generated a combination antibiogram using broth microdilution results from a single tertiary care facility in LA. Results Antibiograms were submitted by 85/100 (85%); 50 hospitals (59%) reported SM (n = 1719 isolates, Table 1). Hospitals commonly (25/50) reported data for

In March 2013, the California Department of Public Health (CDPH) identified two Doctor's First Reports of Occupational Injury or Illness (DFRs) regarding Los Angeles County residents who had worked at the same jobsite in January 2012 and had been evaluated for possible work-associated coccidioidomycosis (valley fever). Occupational exposure to Coccidioides, the causative fungi, typically is associated with soil-disrupting activities. The physicians noted that both workers were cast or crew members filming a television series episode, and the site of possible exposure was an outdoor set in Ventura County, California. On the basis of their job titles, neither would have been expected to have been engaged in soil-disrupting activities. Los Angeles County Department of Public Health (LACDPH) conducted an outbreak investigation by using CDPH-provided occupational surveillance records, traditional infectious disease surveillance, and social media searches. This report describes the results of that investigation, which identified a total of five laboratory-confirmed and five probable cases linked to this filming event. The employer and site manager were interviewed. The site manager stated that they would no longer allow soil-disruptive work at the site and would incorporate information about the potential risk for Coccidioides exposure onsite into work contracts. Public health professionals, clinicians, and the television and film industry should be aware that employees working outdoors in areas where Coccidioides is endemic (e.g., central and southern California), even those not engaged in soil-disruptive work, might be at risk for coccidioidomycosis.

This report details an outbreak investigation conducted by the Los Angeles County Department of Public Health of 3 cases of bacterial infection among patients receiving hemodialysis who were treated at the same dialysis center in 2011. Improper disinfection of reusable dialyzers was hypothesized as the source of transmission.

Objective.Carbapenem-resistant Klebsiella pneumoniae (CRKP) is an emerging multidrug-resistant pathogen associated with higher mortality, longer hospital stays, and increased costs. CRKP was thought to be sporadic in Los Angeles County (LAC); however, the actual incidence is unknown. To address this, LAC declared CRKP a laboratory-reportable disease on June 1, 2010.Design.Laboratory-based community-wide surveillance.Patients.Any individual who was identified as CRKP positive. CRKP was defined as a K. pneumoniae isolate resistant to all carbapenems by 2010 Clinical and Laboratory Standards Institute criteria.Methods.Laboratory directors of 102 LAC acute care hospitals (ACHs) and 5 reference laboratories were to submit susceptibility testing results for all CRKP-positive specimens. Positive specimens from the same patient within the same calendar month of previous culture were excluded.Results.A total of 814 reports were received from June 1, 2010, through May 31, 2011, from 69 laboratories; 675 (83%) met the case definition. Cases were reported from ACHs (387 [57%]), long-term ACHs (LTACs; 231 [34%]), and skilled nursing facilities (57 [8%]); an outbreak in 1 LTAC was identified. The pooled mean incidence rate in LAC ACHs and LTACs was 0.46 per 1,000 patient-days; the rate in LTACs (2.54 per 1,000 patient-days) was higher than that in ACHs (0.31 per 1,000 patient-days; P < .001). Sixty-five individuals had multiple incidences, accounting for 147 case reports.Conclusion.CRKP is more present in LAC than suspected. Rates were consistently higher in LTACs than in ACHs. Heightened awareness of this problem is needed in all LAC healthcare facilities, as patients access services along the continuum of care.

Objective: This study was conducted to obtain a detailed profile of hypothalamo-pituitary-adrenal (HPA) axis activity and reactivity and its differential relationships with body fat distribution and total fat mass in premenopausal obese women. Research Methods and Procedures: Cortisol responses to stimulation (awakening, food intake, exercise) and suppression (0.25 mg dexamethasone), cortisol metabolism, and tissue sensitivity to glucocorticoids were studied in 53 premenopausal obese women grouped according to their waist-to hip ratio: women with abdominal body fat distribution (A-BFD; n = 31) and women with peripheral fat distribution (P-BFD; n = 22). Results: Comparatively, A-BFD women had 1) lower awakening salivary cortisol levels; 2) increased salivary responsiveness to a standardized lunch; 3) similar pituitary sensitivity to dexamethasone but decreased sensitivity of monocytes to dexamethasone; 4) similar 24-hour urinary free cortisol but increased 24-hour urinary ratio of cortisone-to-cortisol; and 5) no difference in corticosteroid binding protein parameters. Discussion: Although abdominal obesity is not very different from generalized obesity in terms of HPA function, subtle variations in HPA axis activity and reactivity are evidenced in A-BFD premenopausal obese women.

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