Vibration analysis of adding contaminants particles and carbon nanotubes to lithium grease of ball bearing

This paper examines vibration behavior of ball bearings dispersed by solid as a function of contamination of lubricant. Experimental tests were performed using SKF 6004 deep groove ball bearing, dispersed with different contaminants particles. Silica sand with different particle sizes, copper (Cu micro particles), poly methyl methacrylate (PMMA), low-density polyethylene (LDPE), and polyamide (PA), all at five concentration levels were used to disperse the lubricant. The contaminants concentration as well as the carbon nanotubes (CNTs) concentration is varied as 1, 2, 3, 4, and 5 wt. %. It was found that as the contaminants particles size and concentration increased, the corresponding acceleration values also increased up to certain limit. Furthermore, the vibration amplitudes decrease due to the increase of the copper concentration. The vibration amplitude was improved due to increase of concentration of carbon nanotubes CNTs

New Horizon in Mobile Communications Networks Planning

The new horizon in mobile communication network planning is a developed study on mobile communication services in developed and developing countries. The aim of the study is to introduce a method to predict the best country for investment in mobile communication services and industry on which the mobile communication networks planning depend. For this purpose the past and current mobile communication services are studied. The data are collected from the communication market reports of developed and developing countries and the questionnaire that was carried out in Iraq. The data are analysed using the SPSS program. The outcome is a regression model that explains the relation between the dependent variable (expenditure on mobile communication services) and the independent variables (age, gender, academic standing, money paid for mobile phone handset, interesting in mobile phone having ability to play movies, maximum price paid for mobile phone that have ability to play movies, the rating of mobile phone service quality, problems during the usage of internet on mobile phone handset, daily usage of mobile phone services, and the satisfaction in mobile phone customer support) which are the instruments used to achieve outcome. The model of the regression equation used is: Y = 3.703 - 0.123X6 + 1.372 X9 + 0.001X10 - 0.173X12 – 0.675X19 - 0.010 X22 - 0.271X24. where Y represent the dependent variable and (X1 to X24) are the independent variables. The research model will contribute toward more robust decision making and better strategic planning The research focuses on mobile communications services in seven countries three from the developed world and four are from the developing world. Data sources for this research relies primarily which on the information obtained from the questionnaire (in English & Arabic languages targeted at operators and users of mobile communications services), a review of published information and market reports of seven countries (USA, UK, Australia, India, Egypt, Syria and Iraq). Such data include technical papers, financial reports and industry specific data. This research also provides an overview of the past history of the product in terms of (value, price trends, application trends, leading producers and their market shares). The historical overview of mobile communication generations from 1G to Beyond 4G (B4G) confirms that the successive developments of new generation is based on outpacing the limitations of the previous one. The results show that more services and smooth global roaming at low cost are possible. This research explains that the quality of mobile communications services depends on the requirements of consumers. The communications services refer to mobile services available to the consumer anytime and anywhere at high transmission speed, using advanced technologies such as Orthogonal Frequency Division Multiplexing (OFDM), MIMO, WiMAX, that allow the internet and mobile services providers to offer broadband services at hundreds of Mbps, with high quality voice, video & multimedia over the internet. Over the past decade, wireless communications has shown exponential growth and will certainly continue to witness spectacular developments due to the emergence of new interactive multimedia applications and highly integrated systems driven by rapid growth in information services and microelectronic devices. At this time, broadband data access at high transmission rates are needed to provide users with packet-based services. The next generation wireless system will consist of complementary systems with a set of different standards and technologies along with different requirements and complementary capabilities, that will offer users ubiquitous wireless connectivity between mobile and desktop computers, games systems, cellular phones, a high network capacity, and throughput at low cost. Studying the market reports of US, UK, Australia, India, Egypt, Syria, and Iraq explains that the future generation of mobile communications is based on the broadband access technologies which gives high quality voice and video services, the mobile Internet phone is a solution of all communications requirements of the people today, because most of the people always are moving, so that the best way to stay in touch with others is through the mobile internet phone

Fowler-Nordheim-like local injection of photoelectrons from a silicon tip

Tunneling between a photo-excited p-type silicon tip and a gold surface is studied as a function of tip bias, tip/sample distance and light intensity. In order to extend the range of application of future spin injection experiments, the measurements are carried out under nitrogen gas at room temperature. It is found that while tunneling of valence band electrons is described by a standard process between the semiconductor valence band and the metal, the tunneling of photoelectrons obeys a Fowler-Nordheim-like process directly from the conduction band. In the latter case, the bias dependence of the photocurrent as a function of distance is in agreement with theoretical predictions which include image charge effects. Quantitative analysis of the bias dependence of the dark and photocurrent spectra gives reasonable values for the distance, and for the tip and metal work functions. For small distances image charge effects induce a vanishing of the barrier and the bias dependence of the photocurrent is exponential. In common with many works on field emission, fluctuations in the tunneling currents are observed. These are mainly attributed to changes in the prefactor for the tunneling photocurrent, which we suggest is caused by an electric-field-induced modification of the thickness of the natural oxide layer covering the tip apex.Comment: 12 pages, 11 figures. Submitted to Phys. Rev.

Characterization of Spontaneous and Induced Puberty in Girls with Turner Syndrome

OBJECTIVE: To characterize puberty in girls with Turner syndrome (TS) and determine whether specific patient characteristics are associated with the timing of menarche. We also sought to compare spontaneous versus induced puberty in these patients. METHODS: Medical records of girls followed in our Pediatric Endocrine clinic for TS from 2007 to 2015 were reviewed. RESULTS: Fifty-three girls were included, of whom 10 (19%) achieved menarche spontaneously and 43 (81%) received hormone replacement therapy (HRT). Of girls receiving HRT, a younger age at estrogen initiation correlated with a longer time to menarche (P = .02), and a mosaic karyotype was associated with a shorter time to menarche (P = .02), whereas no relationship was seen for body mass index, estrogen regimen, or maternal age at menarche. Nineteen girls (44%) receiving HRT had bleeding on estrogen alone at a wide dose range and were more likely to be on transdermal than oral preparations (P = .01). Girls with spontaneous puberty achieved menarche at a younger age (P<.01) and were more likely to have mosaic TS (P = .02). CONCLUSION: Significant variability in the timing of menarche exists among girls with TS. However, age at pubertal induction and karyotype were significantly correlated with age at menarche in our patients. A wide range of estrogen doses is seen in girls who bleed prior to progesterone, suggesting extreme variability in estrogen sensitivity among patients with TS. Girls achieving spontaneous menarche are younger and more likely to have a mosaic karyotype than those with induced menarche. Large-scale prospective studies are needed to confirm these results

Toward integrated conservation of North America's crop wild relatives

North America harbors a rich native flora of crop wild relatives—the progenitors and closely related species of domesticated plants—as well as a range of culturally significant wild utilized plants. Despite their current and potential future value, they are rarely prioritized for conservation efforts; thus many species are threatened in their natural habitats, and most are underrepresented in plant genebanks and botanical gardens. Further coordination of efforts among land management, botanical, and agricultural science organizations will improve conservation and general public awareness with regard to these species. We present examples of productive collaborations focused on wild cranberries (Vaccinium macrocarpon and Vaccinium oxycoccos) and chile peppers (Capsicum annuum var. glabriusculum). We then discuss five shared priorities for further action: (1) understand and document North America's crop wild relatives and wild utilized plants, (2) protect threatened species in their natural habitats, (3) collect and conserve ex situ the diversity of prioritized species, (4) make this diversity accessible and attractive for plant breeding, research, and education, and (5) raise public awareness of their value and the threats to their persistence

A growing disconnection from nature is evident in cultural products

Human connection with nature is widely believed to be in decline, even though empirical evidence on the magnitude and temporal pattern of the change is scarce. Studying works of popular culture in English throughout the 20th century and later, we document a cultural shift away from nature, beginning in the 1950s. Since then, references to nature have been decreasing steadily in fiction, song lyrics, and film storylines. No parallel decline is observed in references to the human-made environment. These findings are cause for concern, not only because they imply foregone benefits from engagement with nature, but also because cultural products are agents of socialization that can evoke curiosity, respect, and concern for the natural world

Characterizing and prognosticating chronic lymphocytic leukemia in the elderly: prospective evaluation on 455 patients treated in the United States.

BACKGROUND: Median age at diagnosis of patients with chronic lymphocytic leukemia (CLL) is \u3e 70 years. However, the majority of clinical trials do not reflect the demographics of CLL patients treated in the community. We examined treatment patterns, outcomes, and disease-related mortality in patients ≥ 75 years with CLL (E-CLL) in a real-world setting. METHODS: The Connect® CLL registry is a multicenter, prospective observational cohort study, which enrolled 1494 adult patients between 2010-2014, at 199 US sites. Patients with CLL were enrolled within 2 months of initiating first line of therapy (LOT1) or a subsequent LOT (LOT ≥ 2). Kaplan-Meier methods were used to evaluate overall survival. CLL- and infection-related mortality were assessed using cumulative incidence functions (CIF) and cause-specific hazards. Logistic regression was used to develop a classification model. RESULTS: A total of 455 E-CLL patients were enrolled; 259 were enrolled in LOT1 and 196 in LOT ≥ 2. E-CLL patients were more likely to receive rituximab monotherapy (19.3 vs. 8.6%; p \u3c 0.0001) and chemotherapy-alone regimens (p \u3c 0.0001) than younger patients. Overall and complete responses were lower in E-CLL patients than younger patients when given similar regimens. With a median follow-up of 3 years, CLL-related deaths were higher in E-CLL patients than younger patients in LOT1 (12.6 vs. 5.1% p = 0.0005) and LOT ≥ 2 (31.3 vs. 21.5%; p = 0.0277). Infection-related deaths were also higher in E-CLL patients than younger patients in LOT1 (7.4 vs. 2.7%; p = 0.0033) and in LOT ≥ 2 (16.2 vs. 11.2%; p = 0.0786). A prognostic score for E-CLL patients was developed: time from diagnosis to treatment \u3c 3 months, enrollment therapy other than bendamustine/rituximab, and anemia, identified patients at higher risk of inferior survival. Furthermore, higher-risk patients experienced an increased risk of CLL- or infection-related death (30.6 vs 10.3%; p = 0.0006). CONCLUSION: CLL- and infection-related mortality are higher in CLL patients aged ≥ 75 years than younger patients, underscoring the urgent need for alternative treatment strategies for these understudied patients. TRIAL REGISTRATION: The Connect CLL registry was registered at clinicaltrials.gov: NCT01081015 on March 4, 2010

Real-world clinical experience in the Connect® chronic lymphocytic leukaemia registry: a prospective cohort study of 1494 patients across 199 US centres.

The clinical course of chronic lymphocytic leukaemia (CLL) is heterogeneous, and treatment options vary considerably. The Connect® CLL registry is a multicentre, prospective observational cohort study that provides a real-world perspective on the management of, and outcomes for, patients with CLL. Between 2010 and 2014, 1494 patients with CLL and that initiated therapy, were enrolled from 199 centres throughout the USA (179 community-, 17 academic-, and 3 government-based centres). Patients were grouped by line of therapy at enrolment (LOT). We describe the clinical and demographic characteristics of, and practice patterns for, patients with CLL enrolled in this treatment registry, providing patient-level observational data that represent real-world experiences in the USA. Fluorescence in&nbsp;situ hybridization (FISH) analyses were performed on 49·3% of patients at enrolment. The most common genetic abnormalities detected by FISH were del(13q) and trisomy 12 (45·7% and 20·8%, respectively). Differences in disease characteristics and comorbidities were observed between patients enrolled in LOT1 and combined LOT2/≥3 cohorts. Important trends observed include the infrequent use of genetic prognostic testing, and differences in patient characteristics for patients receiving chemoimmunotherapy combinations. These data represent experiences of patients with CLL in the USA, which may inform treatment decisions in everyday practice

Effect of Gut Microbiota Biotransformation on Dietary Tannins and Human Health Implications

Tannins represent a heterogeneous group of high-molecular-weight polyphenols that are ubiquitous among plant families, especially in cereals, as well as in many fruits and vegetables. Hydrolysable and condensed tannins, in addition to phlorotannins from marine algae, are the main classes of these bioactive compounds. Despite their low bioavailability, tannins have many beneficial pharmacological effects, such as anti-inflammatory, antioxidant, antidiabetic, anticancer, and cardioprotective effects. Microbiota-mediated hydrolysis of tannins produces highly bioaccessible metabolites, which have been extensively studied and account for most of the health effects attributed to tannins. This review article summarises the effect of the human microbiota on the metabolism of different tannin groups and the expected health benefits that may be induced by such mutual interactions. Microbial metabolism of tannins yields highly bioaccessible microbial metabolites that account for most of the systemic effects of tannins. This article also uses explainable artificial intelligence to define the molecular signatures of gut-biotransformed tannin metabolites that are correlated with chemical and biological activity. An understanding of microbiota–tannin interactions, tannin metabolism-related phenotypes (metabotypes) and chemical tannin-metabolites motifs is of great importance for harnessing the biological effects of tannins for drug discovery and other health benefits

Self-ligating brackets versus conventional pre-adjusted edgewise brackets for treating malocclusion (Protocol).

-National Institute for Health Research (NIHR), UK. -Cochrane Or -al Health Global Alliance, Other