2,654 research outputs found
On the origin of quantum mechanics
Action at distance in Newtonian physics is replaced by finite propagation
speeds in classical post--Newtonian physics. As a result, the differential
equations of motion in Newtonian physics are replaced by functional
differential equations, where the delay associated with the finite propagation
speed is taken into account. Newtonian equations of motion, with
post--Newtonian corrections, are often used to approximate the functional
differential equations. Are the finite propagation speeds the origin of the
quantum mechanics? In this work a simple atomic model based on a functional
differential equation which reproduces the quantized Bohr atomic model is
presented. As straightforward application of the result the fine structure of
the hydrogen atom is approached.Comment: 16 pages, 1 figure in EPS forma
Enterprise 4.0 – the emerging digital transformed enterprise?
Information Systems are at the core of all businesses and cover almost all aspects of organizational life. The convergence of computer capabilities, such as the potential to process large volumes of data in a very short time, the growth in Internet usage and the increase in the ability to capture and leverage knowledge in digital format are, in this context, the main enablers of the so called digital transformation of organizations. While the technology enablers allow the production, sharing and management of information and knowledge within the organization between peers and other stakeholders, besides empowering the improvement and innovation of the organizational processes, they also require the updating of the supporting IS. Thus, using technologies in organizations within the context of Digital Transformation (DT) requires an exercise in understanding how to demonstrate their usefulness in relation to the creation, access and sharing of contents and IS improvements in a safe way. This paper provides a comprehensive view of a new context of labour faced within DT of organizations, which we term Enterprise 4.0 and which we propose to be implemented through the m_CSDIT framework, so as to improve the organizational well-being considering the collective intelligence and agility dimensions.Project Management(undefined
Influence of feeding Mediterranean food industry by-products and forages to Awassi sheep on physicochemical properties of milk, yoghurt and cheese
Feeding agro-industrial by-products and unconventional forages, rich in potentially anti-nutritional factors, may influence the quality of the raw milk and the dairy products prepared therefrom. The aim of the present study was to determine side-effects on physicochemical properties of milk, yoghurt and cheese of feeding diets where one third were feeds either rich in lipids (tomato pomace and olive cake) or phenols (olive leaves and lentil straw) or electrolytes (Atriplex leaves). The diets, including a control diet, were designed to be isoenergetic and isonitrogenous. They were fed in amounts of 2 5 kg dry matter/day per head during 50 days to 6×10 multiparous fat-tailed Awassi ewes. Milk samples were analysed for various physicochemical traits and fatty acid composition on days 0, 24, 36 and 48. Three times, milk pooled by group was processed to yoghurt and non-aged farmer-type cheese, which were analysed for their gross and fatty acid composition and texture, and were subjected to sensory evaluation. Feeding olive cake and tomato pomace reduced milk casein, but increased proportions of monounsaturated fatty acids. There were some variations in minerals among test diets but, contrary to expectations, Atriplex did not increase milk sodium. The nutritional composition of yoghurt and cheese was not varied much by the test feeds, except for some changes in fatty acid profile similar to the milk. Yoghurt firmness declined with all test diets, but texture score tended to be lower only for olive cake and leaf diets relative to control. Cheese firmness was increased by feeding the Atriplex leaf and olive cake diets which was also reflected in the texture scores. No off-flavours were reported. Possible reasons for effects on the dairy products are discussed. In conclusion, the feeds investigated had certain effects on the physicochemical properties of dairy products, but these were neither very systematic nor large thus not prohibiting their use in Mediterranean sheep milk production system
Vocational perspectives after spinal cord injury
Objective: To give insight into the vocational situation several years after a traumatic spinal cord injury (SCI) and describe the personal experiences and unmet needs; to give an overview of health and functional status per type of SCI and their relationship with employment status. Design: Descriptive analysis of data from a questionnaire. Setting: Dutch rehabilitation centre with special department for patients with spinal cord injuries. Subjects: Fifty-seven patients with a traumatic SCI, aged 18-60 years, admitted to the rehabilitation centre from 1990 to 1998. Main measures: Questionnaire with items related to vocational outcome, job experiences, health and functional status. Results: Of 49 patients who were working at the moment of SCI 60% currently had a paid job. Vocational outcome was related to a higher educational level. A significant relation between the SCI-specific health and functional status and employment was not found. The respondents who changed to a new employer needed more time to resume work, but seemed more satisfied with the job and lost fewer working hours than those who resumed work with the same employer. In spite of reasonable to good satisfaction with the current work situation, several negative experiences and unmet needs were reported. Conclusions: Despite a high participation in paid work following SCI, the effort of the disabled worker to have and keep a job should not be underestimated
Schistosomiasis and Urinary Bladder Cancer in North Western Tanzania: A Retrospective Review of 185 Patients.
Worldwide, cancers of the urinary bladder are well known to be associated with environmental chemical carcinogens such as smoking and occupational exposure to polycyclic aromatic hydrocarbons. These cancers are typically transitional cell carcinoma (urothelial carcinoma). In areas where schistosomiasis is endemic there is a high incidence of squamous cell carcinoma of the urinary bladder. Schistosomiasis causes chronic granulomatous cystitis leading to squamous metaplasia of transitional epithelium, and subsequently development of squamous cell carcinoma. The western part of Tanzania on the shores of Lake Victoria is such an endemic area. This study was done to document the burden of urinary bladder cancer associated with schistosomiasis in this region. This was a descriptive retrospective study of histologically confirmed cases of urinary bladder cancer seen at the Department of Pathology Bugando Medical Centre (BMC) over a period of 10 years. Data were retrieved from the records of the Departments of Pathology, Medical Records and Surgery. Data were analyzed by the use of contingency tables. A total of 185 patients were diagnosed with cancer of the urinary bladder during the study period, where as 90 (48.6%) were males and 95 (51.4) were females. The mean age at diagnosis was 54.3 years. Squamous cell carcinoma was the most frequent histological type (55.1%), followed by conventional transitional cell carcinoma (40.5%). Eighty three of all cancer cases (44.9%) were found to have schistosomal eggs. Schistosomiasis was commonly associated with squamous cancers compared to non squamous cancers. Most of the cancers associated with schistosomiasis had invaded the muscularis propria of the urinary bladder at the time of diagnosis (p<0.001) and such cancers were frequent below 50 years of age with a significant statistical difference (p<0.001). Poorly differentiated tumors were more frequent in females than males with a significant statistical difference (p=0.006). The majority of urinary bladder cancers seen in the Lake Region were squamous cell carcinoma associated with schistosomiasis. These cancers showed an aggressive behavior and were commonly seen in the younger age groups. Effective control of schistosomiasis in this region should significantly reduce the burden of urinary bladder cancer
Study of the effects of Pauli blocking and Pauli non-locality on the optical potential
Elastic scattering angular distributions for systems with reduced mass
between 3 and 34 and energies varying between 25 and 120 MeV/nucleon were
analyzed. The stable He, its exotic partner He, and the weakly bound
Li nuclei were included as projectiles in the systematics. Optical
model data analyzes were performed with an adjustable factor of normalization
included in the imaginary part of the potential. These analyzes indicated a
reduction of absorption for systems with small reduced masses that was detected
due to the refractive nature of the scattering by light systems.Comment: 16 pages, 7 figure
Molecular identification of adenoviruses associated with respiratory infection in Egypt from 2003 to 2010.
BACKGROUND: Human adenoviruses of species B, C, and E (HAdV-B, -C, -E) are frequent causative agents of acute respiratory infections worldwide. As part of a surveillance program aimed at identifying the etiology of influenza-like illness (ILI) in Egypt, we characterized 105 adenovirus isolates from clinical samples collected between 2003 and 2010. METHODS: Identification of the isolates as HAdV was accomplished by an immunofluorescence assay (IFA) and confirmed by a set of species and type specific polymerase chain reactions (PCR). RESULTS: Of the 105 isolates, 42% were identified as belonging to HAdV-B, 60% as HAdV-C, and 1% as HAdV-E. We identified a total of six co-infections by PCR, of which five were HAdV-B/HAdV-C co-infections, and one was a co-infection of two HAdV-C types: HAdV-5/HAdV-6. Molecular typing by PCR enabled the identification of eight genotypes of human adenoviruses; HAdV-3 (n = 22), HAdV-7 (n = 14), HAdV-11 (n = 8), HAdV-1 (n = 22), HAdV-2 (20), HAdV-5 (n = 15), HAdV-6 (n = 3) and HAdV-4 (n = 1). The most abundant species in the characterized collection of isolates was HAdV-C, which is concordant with existing data for worldwide epidemiology of HAdV respiratory infections. CONCLUSIONS: We identified three species, HAdV-B, -C and -E, among patients with ILI over the course of 7 years in Egypt, with at least eight diverse types circulating
Coexistence and Phase Separation in Sheared Complex Fluids
We demonstrate how to construct dynamic phase diagrams for complex fluids
that undergo transitions under flow, in which the conserved composition
variable and the broken-symmetry order parameter (nematic, smectic,
crystalline, etc.) are coupled to shear rate. Our construction relies on a
selection criterion, the existence of a steady interface connecting two stable
homogeneous states. We use the (generalized) Doi model of lyotropic nematic
liquid crystals as a model system, but the method can be easily applied to
other systems, provided non-local effects are included.Comment: 4 pages REVTEX, 5 figures using epsf macros. To appear in Physical
Review E (Rapid Communications
Carbohydrate antigen 19‐9 is a prognostic and predictive biomarker in patients with advanced pancreatic cancer who receive gemcitabine‐containing chemotherapy
BACKGROUND: Carbohydrate antigen 19‐9 (CA19‐9) is a widely used biomarker in pancreatic cancer. There is no consensus on the interpretation of the change in CA19‐9 serum levels and its role in the clinical management of patients with pancreatic cancer. METHODS: Individual patient data from 6 prospective trials evaluating gemcitabine‐containing regimens from 3 different institutions were pooled. CA19‐9 values were obtained at baseline and after successive cycles of treatment. The objective of this study was to correlate a decline in CA19‐9 with outcomes while undergoing treatment. RESULTS: A total of 212 patients with locally advanced (n = 50) or metastatic (n = 162) adenocarcinoma of the pancreas were included. Median baseline CA19‐9 level was 1077 ng/mL (range, 15‐492,241 ng/mL). Groups were divided into those levels below (low) or above (high) the median. Median overall survival (mOS) was 8.7 versus 5.2 months ( P = .0018) and median time to progression (mTTP) was 5.8 versus 3.7 months ( P = .082) in the low versus high groups, respectively. After 2 cycles of chemotherapy, up to a 5% increase versus ≥ 5% increase in CA19‐9 levels conferred an improved mOS (10.3 vs 5.1 months, P = .0022) and mTTP (7.5 vs 3.5 months, P = 0.0005). CONCLUSIONS: In patients who have advanced pancreatic cancer treated with gemcitabine‐containing regimens baseline CA19‐9 is prognostic for outcome. A decline in CA19‐9 after the second cycle of chemotherapy is not predictive of improved mOS or mTTP; thus, CA19‐9 decline is not a useful surrogate endpoint in clinical trials. Clinically, a ≥ 5% rise in CA19‐9 after 2 cycles of chemotherapy serves as a negative predictive marker. Cancer 2013. © 2012 American Cancer Society. Baseline carbohydrate antigen 19‐9 (CA19‐9) is prognostic for outcomes in patients with pancreatic adenocarcinoma. Change in CA19‐9 serum level up to a 5% increase from baseline remains predictive for response to gemcitabine‐containing therapy, and thus should be considered a negative predictor.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/96409/1/27734_ftp.pd
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