BackgroundPhysical and biological properties of dust particles might affect the availability and distribution of chemicals associated to indoor dust; however it has not been adequately examined. In this study, household dust from Shanghai was fractionated into five particle sizes and size distribution, morphology, surface area, organic matter, microorganisms, elemental composition, metals and organophosphorus flame retardants (OPFRs) compositions were characterized. Also, household dust samples from Stockholm that has previously been characterized were included in the analysis of OPFRs for comparison.ResultsThe respirable fraction had a yield of 3.3% in mass percentage, with a particle size of 2.22 ± 2.04 µm. As expected, both metals and OPFRs concentrations increased with decreased particle size. Al and Fe dominated (66–87%) followed by the concentrations of Zn (5–14%) and Ga (1.8–5%) of the sum of 16 metals in the dust. The concentrations of OPFRs in Shanghai dust ranged from 5.34 to 13.7 µg/g (median: 7.21 µg/g), compared to household dust from Stockholm that ranged from 16.0 to 28.3 µg/g (median: 26.6 µg/g). Tris(2-chloroisopropyl) phosphate (TCIPP) and tris(2-chloroethyl) phosphate (TCEP) dominated in Shanghai dust samples while tris(2-butoxyethyl) phosphate (TBOEP) dominated in dust from Stockholm homes.ConclusionThe results showed that mass percentage for each particle size fraction was not evenly distributed. Furthermore, the particle-bound microorganisms and OPFRs increased with decreased particle size, whereas metals had the highest concentrations at specific dust sizes. Therefore, it is essential to select the proper particle size in order to assess any specific human exposure study to indoor pollutants.
Malawi is midway through its current Malaria Strategic Plan 2017–2022, which aims to reduce malaria incidence and deaths by at least 50% by 2022. Malariometric data are available with health surveillance data housed in District Health Information Software 2 (DHIS2) and household survey data from two recent Malaria Indicator Surveys (MIS) and a Demographic and Health Survey (DHS). Strengths and weaknesses of the data were discussed during a consultative meeting in Lilongwe, Malawi in July 2019. The first 3 days included in-depth exploration and analysis of surveillance and survey data by 13 participants from the National Malaria Control Programme, district health offices, and partner organizations. Key indicators derived from both DHIS2 and MIS/DHS sources were analysed with three case studies, and presented to stakeholders on the fourth day of the meeting. Applications of the findings to programmatic decision-making and strategic plan evaluation were critiqued and discussed.
Bottled water sector in B&H becomes more significant economically with media pressure and expectations. This paper aims to determine factors important for the consumers while choosing bottled water products and in that way try to, by comparing the results to the sectors abilities, determine sector’s ability to meet the consumer’s needs. Small research among (97) respondents was carried out, and the results indicate that the sector is unable to meet the needs of the customers, since the trade balance is negative and domestic market share low. Customer profile suggests almost only young consumers, which indicates that for the stronger results further research is needed.
SUMMARY Bone tissue banks are necessary for collection, production, testing, packaging, storage and delivery of bone transplants. Bone tissue bank is a link between the donor and the recipient by which the donation becomes a medium of health improvement for both the donor and the recipient. At the Department of Orthopedics, Mostar University Clinical Hospital, about 200 total hip replacements are performed per year. Most patients undergoing total hip replacement surgery (90%) have been diagnosed with osteoarthritis, and they are suitable donors, having in mind their age and comorbidities. In the same Department, around 50 procedures that require bone transplants are performed per year. A team of highly competent surgeons are working on an intensive process of adaptation oriented to quality improvement and intensification of the activity, both with the goal of meeting the standards of excellence in orthopedic surgery. The presence of a bone tissue bank has a favorable impact on the quality of health care owing to bone transplant availability, as well as on the scientific role of a highly specialized institution that examines the properties of bone tissue.
Introduction: Basal cell carcinoma (BCC) is a non-melanocytic skin malignancy arising from basal cells of epidermis or follicular structures. Etiology of BCC is a multifactorial combination of genotype, phenotype, and environmental factors. There are several clinical variants of BCC including nodular, cystic, superficial, morphoeic, keratotic, pigmented and micronodular. Aim: The aim of our study was to analyze the recent clinical trends of basal cell carcinoma by reviewing a single institution’s experience. Methods: Total number of 422 patients clinically diagnosed with basal cell carcinoma were included in the study. Data on age, gender, skin type, personal and family history, duration of disease, localization of lesions, clinical type of lesions, and recurrence rate were collected and analyzed. The data were statistically evaluated. Results: More than 80% of all BCC’s were located on sun-exposed skin areas (p<0.05).The male /female ratio was 1:0.92. The nodular BCC was the most frequent type (59.2%), followed by the superficial (16.1%), pigmented (15.2%) and morphoeic (9.5%) types. The nodular and pigmented types were predominant located on the head and neck, whereas the trunk was the most common location for the superficial type (p<0.05). The tumor is commonly found in concomitance with skin lesion related to chronic sun exposure, such as actinic keratoses, solar lentigines and facial telangiectasia. During this study period, 41 cases showed recurrence of the cancer as the overall recurrence rate was 9.7%. There were no cases with metastasis or fatal outcome. Conclusions: The factors related to the development of BCC were older age and exposure to ultraviolet rays both in recreational and in occupational form. The prevention of BCC is based on the knowledge of risk factors, early diagnosis and treatment, particularly in susceptible populations.
Breast cancer consists of several intrinsic molecular subtypes, providing the basis for clinical treatment decisions. Lately, it is becoming increasingly recognized that factors other than the intrinsic cancer characteristics, such as immune components’ activity in the tumor microenvironment, have important effects on treatment choices and efficacy. bioSyntagma has developed a method, the Molecular Fingerprint (mPrint®), that enables multiplexed analysis of spatially defined regions in formalin-fixed, paraffin-embedded (FFPE) tumor samples allowing for analysis of the gene signatures unique to the tumor microenvironment. This method was applied to molecularly defined sets of breast cancers and used to evaluate four different tumor regions of interest (ROIs): 1) viable carcinoma proper (>90% cancer cells), 2) fibrotic tumor center (sparse cellularity), 3) interface between viable tumor and inflammatory component (tumor and inflammatory microenvironment) and 4) tissue away from the tumor (normal breast tissue). This was compared to the whole tissue scrapes from each patient block. Each ROI and tissue scrape was analyzed by high throughput qPCR for a panel of 248 genes using SmartChip technology (Takara Bio, USA). Sequential tissue slices from each patient were also analyzed using immunohistochemistry (IHC) for three targets and investigated for correlation with qPCR results for validation of the method. Overall, reasonable concordance was observed in general expression trends between selected IHC and RNA expression. qPCR data were further analyzed using hierarchical clustering analysis and showed that morphologically defined ROI’s cluster completely differently than traditional clustering of entire tissue scrapes. Notably, patient clustering based on morphological regions was independent of the intrinsic cancer subtype, as determined by molecular profiling of whole tissue scrapes, as well as independent of trends in Tumor Mutational Burden (TMB) and Microsatellite Instability (MSI). These findings suggest that current methods of patient stratification based on whole tumor molecular subtyping may be inferior to stratification based on molecular characteristics of the tumor microenvironment. Citation Format: Colleen Ziegler, Isaiah Slemons, Chris DeSilva, Barbara Witkowski, Alain Mir, Sangeetha Anandakrishnan, Andrew Farmer, Elma Contreras, David Richardson, Semir Vranic, Zoran Gatalica, Dmitry N. Derkach. Novel method for patient stratification in breast carcinoma based upon spatial analysis of tumor microenvironment [abstract]. In: Proceedings of the AACR-NCI-EORTC International Conference on Molecular Targets and Cancer Therapeutics; 2019 Oct 26-30; Boston, MA. Philadelphia (PA): AACR; Mol Cancer Ther 2019;18(12 Suppl):Abstract nr B094. doi:10.1158/1535-7163.TARG-19-B094
Abstract The main aim of this paper is to investigate the productivity changes of microfinance institutions (MFIs) in Bosnia and Herzegovina (BiH) during and after the recent financial crisis. The study covers the period starting from 2008 until 2015. Using the Malmquist Productivity Index (MPI) over the sample of 10 MFIs and a balanced panel dataset of 80 observations, this study explores technical and technological change as well as total factor productivity (TFP) change. The empirical findings indicate a decline in TFP in most of the analyzed periods with an average decrease of 2.5%. The study reveals an average technological decline in the industry of 1.7%, while technical efficiency change is recorded at the level of -0.8%. Overall, crisis efficiency recovery occurred during the period between 2009 and 2013. However, due to technological inefficiencies, average total factor productivity change remains negative. Hence, policy makers need to enhance the technological progress in order to meet their strategic objectives in BiH MFIs.
Introduction The workplace can be a source of stress. One of the most stressful professions is the profession of doctor of dental medicine (dentist). Multiple forms of stressors lead to such occupational stress. Objective The research objective was to examine stress levels among dentists in the 25 to 45 year age group. Materials and Methods This cross sectional study included 105 doctors of dental medicine throughout Bosnia and Herzegovina, aged between 25 and 45 years. The research was conducted by means of a confidential on-line survey. All participants signed the informed consent, and voluntarily filled out the survey form. The research used the PERCEIVED STRESS SCALE-PSS 10. The statistical analysis used the IBM Statistics SPSS v.21 statistics packages and Microsoft Excel 2010. Descriptive statistics, X2 test, and T-test were also used. Results Of the total number of respondents, n=105, 66 (63%) of them were female and 39 (37%) male respondents. The mean median value of the score was 23 (Mean = 23.080), as a result of which we can conclude that the respondents in the 25-45 year age population group that participated in this study showed a high level of stress based on the completed questionnaire and the answers received from the respondents. Conclusion The estimated level of stress has been shown to be high in both genders, with no statistically significant difference between genders.
Most extremum-seeking control approaches focus solely on the problem of finding the extremum of some unknown, steady-state performance map. However, many industrial applications also have to deal with constraints on operating conditions due to, e.g., actuator limitations, limitations on design or tunable system parameters, or constraints on measurable signals. These constraints, which can be unknown a-priori, may conflict with the otherwise optimal operational condition, and should be taken into account in performance optimization. In this work, we propose a sampled-data extremum-seeking approach for optimization of constrained dynamical systems using barrier function methods, where both the objective function and the constraint function are available through measurement only. We show that, under the assumption that initialization does not violate constraints, the interconnection between a constrained dynamical system and optimization algorithms that employ barrier function methods is stable, the constraints are satisfied, and optimization is achieved. We illustrate the results by means of a numerical example.
We propose a novel triggering policy to implement state-feedback controllers for nonlinear systems via packet-based communication networks. The idea is to generate transmissions between the plant and the controller only when a state-dependent rule has been satisfied for a given amount of time. We refer to this new paradigm as event-holding control, in which a clock variable is thus only running when a state-dependent criterion is verified. This is different from time-regularized event-triggered control, where the clock variable keeps running after each transmission instant until it is reset to zero at the moment a state-based condition is verified. We approach the problem of designing an event-holding controller via emulation. We first synthesize a state-feedback law, which stabilizes the closed-loop system in the absence of the communication network. We then design the event-holding triggering mechanism under a set of general assumptions. The results are applied to two case studies consisting of linear systems and a class of nonlinear systems controlled by backstepping. We also provide a numerical backstepping control example, which demonstrates that the event-holding behaviour can reduce the number of transmissions.
Value iteration is a method to generate optimal control inputs for generic nonlinear systems and cost functions. Its implementation typically leads to approximation errors, which may have a major impact on the closed-loop system performance. We talk in this case of approximate value iteration (AVI). In this paper, we investigate the stability of systems for which the inputs are obtained by AVI. We consider deterministic discrete-time nonlinear plants and a class of general, possibly discounted, costs. We model the closed-loop system as a family of systems parameterized by tunable parameters, which are used for the approximation of the value function at different iterations, the discount factor and the iteration step at which we stop running the algorithm. It is shown, under natural stabilizability and detectability properties as well as mild conditions on the approximation errors, that the family of closed-loop systems exhibit local practical stability properties. The analysis is based on the construction of a Lyapunov function given by the sum of the approximate value function and the Lyapunov-like function that characterizes the detectability of the system. By strengthening our conditions, asymptotic and exponential stability properties are guaranteed.
We study a class of distributed optimization problems of minimizing the sum of potentially non-differentiable convex objective functions (without requiring strong convexity). A novel approach to the analysis of asynchronous distributed optimization is developed. An iterative algorithm based on dual decomposition and block coordinate ascent is implemented in an edge based manner. We extend available results in the literature by allowing multiple and potentially overlapping blocks to be updated at the same time with non-uniform probabilities assigned to different blocks. Sublinear convergence with probability one is proved for the algorithm under the aforementioned weak assumptions. A numerical example is provided to illustrate the effectiveness of the algorithm.
Most emulation-based results in networked control systems rely on a bound on the maximal allowable transmission interval (MATI) under which stability is preserved. However, having only such a MATI condition can lead to conservative results, as large values of transmission intervals may only occur sporadically, while the typical transmission interval is much smaller. In this paper, we therefore propose, in addition to the existence of a MATI, to also impose a bound on the average allowable transmission interval, expressed in terms of a reverse average dwell-time (RADT) condition on the transmission intervals. We provide joint conditions on the RADT and the MATI such that stability of the NCS can still be guaranteed, which can, in addition, lead to significant higher values of the MATI itself. The strengths of these new results are illustrated on a numerical example, showing a 484% improvement of the MATI, while still guaranteeing stability.
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