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Quantum Packet for the Next Generation Network/ISDN3

  • Lam, Ray Y. W.;Chan, Henry C. B.;Chen, Hui;Dillon, Tharam S.;Li, Victor O. K.;Leung, Victor C. M.
    • Journal of Communications and Networks
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    • v.10 no.3
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    • pp.316-330
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    • 2008
  • This paper proposes a novel method for transporting various types of user traffic effectively over the next generation network called integrated services digital network 3 (ISDN3) (or quantum network) using quantum packets. Basically, a quantum packet comprises one or more 53-byte quanta as generated by a "quantumization" process. While connection-oriented traffic is supported by fixed-size quantum packets each with one quantum to emulate circuit switching, connectionless traffic (e.g., IP packets and active packets) is carried by variable-size quantum packets with multiple quanta to support store-and-forward switching/routing. Our aim is to provide frame-like or datagram-like services while enabling cell-based multiplexing. The quantum packet method also establishes a flexible and extensible framework that caters for future packetization needs while maintaining backward compatibility with ATM. In this paper, we discuss the design of the quantum packet method, including its format, the "quantumization" process, and support for different types of user traffic. We also present an analytical model to evaluate the consumption of network resources (or network costs) when quantum packets are employed to transfer loss-sensitive data using three different approaches: cut-through, store-and-forward and ideal. Close form mathematical expressions are obtained for some situations. In particular, in terms of network cost, we discover two interesting equivalence phenomena for the cut-through and store-and-forward approaches under certain conditions and assumptions. Furthermore, analytical and simulation results are presented to study the system behavior. Our analysis provides valuable insights into the. design of the ISDN3/quantum network.

Status of Laboratory Biosafety and Biosecurity in Veterinary Research Facilities in Nigeria

  • Odetokun, Ismail Ayoade;Jagun-Jubril, Afusat Toyin;Onoja, Bernard A.;Wungak, Yiltawe Simwal;Raufu, Ibrahim Adisa;Chen, Jessica Corron
    • Safety and Health at Work
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    • v.8 no.1
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    • pp.49-58
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    • 2017
  • Background: This study determined current status of laboratory biosafety in Nigerian veterinary research facilities. Methods: A questionnaire was developed to obtain information from researchers across Nigeria from July 2014 to July 2015. Information regarding demographics, knowledge of laboratory biosafety, availability and proper use of personal protective equipment (PPE), any priority pathogens researched, attitude on and use of standard laboratory practices, and biosafety awareness was obtained using a numeric scoring system. Data were analyzed with descriptive statistics, and univariate and multivariate logistic regression. Results: A total of 74 participants from 19 facilities completed the questionnaire. General knowledge scores ranged from 3 to 28 (out of 28 possible points), with 94.6% of respondents receiving low scores (scores < mean + 1 standard deviation). Very few (17.6%) reported availability or use PPE. Many participants (63.5%) reported no access to biosafety level (BSL)-1-3 facilities. None reported availability of a BSL-4 facility. Knowledge scores pertaining to biosafety management practices ranged from 0 to 14 (out of 14 possible points) with 47.3% of respondents receiving good scores (scores > mean + 1 standard deviation). Only 16.2% of respondents (from four facilities) reported having biosafety officers. Rabies virus was the most researched pathogen (31.1% of respondents). The majority (71.6%) were unaware of laws guiding biosafety. Researchers [odds ratio (OR) = 18.0; 95% confidence interval (CI): 1.63, 198.5; p = 0.023], especially in BSL-2 (OR = 258.5; 95% CI: 12.71, 5256; p < 0.001) facility of research institute (OR = 25.0; 95% CI: 5.18, 120.6; p < 0.001), are more likely to have adequate access to and properly utilize biosafety devices and PPE. Conclusions: Current knowledge of laboratory biosafety is limited except among a few researchers.

Inhibitory effect of therapeutic genes, cytosine deaminase and interferon-β, delivered by genetically engineered stem cells against renal cell carcinoma

  • Gyu-Sik Kim;Soo-Min Kim;Seung U. Kim;Gabsang Lee;Kyung-Chul Choi
    • Oncology Reports
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    • v.43 no.6
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    • pp.2045-2052
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    • 2020
  • Although the effects of stem cells expressing anticancer genes on tumor growth have been demonstrated by many researchers in various types of cancer, relatively few studies have investigated their inhibitory effects on cancer metastasis. In the present study, we examined the inhibitory effects of cytosine deaminase (CD)/5-fluorocytosine (5-FC) and interferon-β (IFN-β) using genetically engineered neural stem cells (hNSCs) in a cellular and metastasis model of renal cell carcinoma (RCC). The CD/5-FC method has the advantage of minimizing damage to normal tissues since it selectively targets cancer cells by the CD gene, which converts prodrug 5-FC to the drug 5-fluorouracil. Moreover, we used hNSCs as a tool to effectively deliver the anticancer genes to the tumor site. These stem cells are known to possess tumor-tropism because of chemoattractant factors expressed in cancer cells. Therefore, we ascertained the expression of these factors in A498 cells, a cell line of RCC, and identified the A498-specific migration ability of hNSCs. We also confirmed that the proliferation of A498 cells was significantly reduced by therapeutic hNSCs in the presence of 5-FC. Furthermore, we established an A498 metastasis model. In the animal experiment, the weight of the lungs increased in response to cancer metastasis, but was normalized by hNSCs expressing CD and/or IFN-β genes, while the incidence of liver metastasis was suppressed by the hNSCs. Overall, the results of this study demonstrate that stem cells expressing anticancer genes have the potential for use as an alternative to conventional therapy for metastatic cancer.

Effects of Surfactant Tween 80 on Forage Degradability and Microbial Growth on the In vitro Rumen Mixed and Pure Cultures

  • Goto, M.;Bae, H.;Lee, S.S.;Yahaya, M.S.;Karita, S.;Wanjae, K.;Cheng, K.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.5
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    • pp.672-676
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    • 2003
  • Effect of a surfactant Tween 80 on the bacterial growth in the rumen was examined on the in vitro pure cultures of Streptococcus bovis, Selenomonas ruminantium, Butyrivibrio fibrisolvens, Prevotella ruminicola, Megasphaera elsidenni, Fibrobacta succinogenes, Ruminanococcus albus and Ruminococcus flavefaciens. Dry matter degradability (DMD), concentrations and compositions of volatile fatty acids (VFA), and the most probable number (MPN) of cellulolytic bacteria and total number of bacteria in the presence of Tween 80 were also examined on the in vitro rumen mixed culture either with barley grain or orchardgrass hay. The growth of S. bovis, S. ruminantium, B. fibrisolvens, P. ruminicola, M. elsidenni and F. succinogenes were significantly higher (p<0.05) at over 0.05% concentrations of Tween 80 than those of the control cultures, while was not changed with R. albus and R. flavefaciens. With rumen mixed culture the DMD of barley grain and orchardgrass hay was significantly higher (p<0.05) at a 0.2% concentration of Tween 80 than the control, being reflected in the significantly higher (p<0.05) VFA production (mmol $g^{-1}$DDM) with orchardgrass hay. The higher (p<0.05) ratio of propionate to acetate at a 0.2% concentration of Tween 80 was also observed with orchardgrass hay, showing a similar trend with barley grain. No changes in the total bacterial number and MPN of cellulolytic bacteria were observed.

Production of Cloned Calves by the Transfer of Somatic Cells Derived from Frozen Tissues Using Simple Portable $CO_2$ Incubator

  • Dong, Y.J.;Bai, X.J.;Varisanga, M.D.;Mtango, N.R.;Otoi, T.;Rajamahendran, R.;Suzuki, T.
    • Asian-Australasian Journal of Animal Sciences
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    • v.17 no.2
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    • pp.168-173
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    • 2004
  • The ability of frozen-thawed fetal skin was examined to generate viable cell lines for nuclear transfer. Fetal skin frozen at -20$-20^{\circ}C$, $-30^{\circ}C$ or $-80^{\circ}C$ in the presence of 5% DMSO used as tissue explants to generate somatic cells. The resultant confluent cells were then used as donors for nuclear transfer (NT). Of the bovine NT embryos reconstracted from the somatic cells, 62.3%, 76.6% to 65% showed cleavage 70.5%, 81.9% to 78.5% reached the stage of morula formation and 39.7%, 43.2% or 47.6% reached the blastocyst stage. There was no significant difference in development when the NT embryos were compared with those reconstracted from fresh somatic cell derieved skin tissues (72%, 75.3%, and 45.2%, for cleavage, and development to morula and blastocyst stage, respectively). NT embryos were then placed in a portable $CO_2$ incubator and carried to China from Japan by air. After reaching to farm, two NT embryos were transferred to each of 5 recipients. We obtained 2 NT calves which birth weights is 30kg and 36kg female, and gestation periods is 281 and 284 days, respectively. There were no observation any abnormality from those calves. The results indicated that cell lines derieved from bovine fetal skin cryopreserved by a simple method could be used as donors in nuclear transfer using the portable $CO_2$ incubator.

Esthetic outcome for maxillary anterior single implants assessed by different dental specialists

  • Al-Dosari, Abdullah;Al-Rowis, Ra'ed;Moslem, Feras;Alshehri, Fahad;Ballo, Ahmed M.
    • The Journal of Advanced Prosthodontics
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    • v.8 no.5
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    • pp.345-353
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    • 2016
  • PURPOSE. The aim of this study was to assess the esthetic outcome of maxillary anterior single implants by comparing the esthetic perception of dental professionals and patients. MATERIALS AND METHODS. Twenty-three patients with single implants in the esthetic zone were enrolled in this study. Dentists of four different dental specialties (Three orthodontists, three oral surgeons, three prosthodontists, and three periodontists) evaluated the pink esthetic score (PES)/white esthetic score (WES) for 23 implant-supported single restorations. The satisfactions of the patients on the esthetic outcome of the treatment have been evaluated according to the visual analog scale (VAS). RESULTS. The mean total PES/WES was $12.26{\pm}4.76$. The mean PES was $6.45{\pm}2.78$ and mean WES was $5.80{\pm}2.82$. There was a statistically significant difference among the different specialties for WES (P<.01) and Total PES/WES (P<.01). Prosthodontists were found to have assigned poorer ratings among the other specialties, while oral surgeons gave the higher ratings than periodontists, orthodontists, and prosthodontists. CONCLUSION. Prosthodontists seemed to be stricter when assessing aesthetic outcome among other specialties. Moreover, a clear correlation existed between dentists' and patients' esthetic perception, thereby providing rationales for involving patients in the treatment plan to achieve higher levels of patient satisfaction.

Long-Haul Truck Driver Training Does Not Meet Driver Needs in Canada

  • Malkin, Jennifer;Crizzle, Alexander M.;Zello, Gordon;Bigelow, Philip;Shubair, Mamdouh
    • Safety and Health at Work
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    • v.12 no.1
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    • pp.35-41
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    • 2021
  • Introduction: Training standards for long-haul truck drivers (LHTD) are rapidly evolving in Canada, yet the opinions of the drivers themselves have not been adequately considered. The purpose was to survey LHTD on their work training history and to examine LHTD perceptions of driver training and licensing protocols. Methods: LHTD were recruited across two Western Canadian provinces from seven different truck stops. The sample completed 207 surveys and 67 semi-structured interviews. Results: The average age of the participants was 52.5 ± 11.5 years (range 24-79); 96% were men. Approximately 33% of the LHTD had at least one crash. Those who did not receive formal driver training were significantly more likely to crash than those who had received training. Participants stated that current training standards are inadequate for the industry, particularly for new drivers. According to participants, entry-level curriculums should consist of both classroom and practical training, as well as on-road observation with a senior mentor. LHTD reported that many new drivers are not equipped to drive in various contexts and settings (e.g., mountains, slippery roads). Conclusions: LHTD are not confident in the current training guidelines for novice truck drivers. Revisions to the training curriculum and standardization across Canada should be considered. Practical Application: A federal mandatory entry-level training program is needed in Canada to ensure that all new LHTD ascertain the necessary skills to drive safely. Such a program requires government involvement and input from LHTD to facilitate appropriate licensure and consistent training for all drivers.

Prevalence and extension of the anterior loop of the mental nerve in different populations and CBCT imaging settings: A systematic review and meta-analysis

  • Hadilou, Mahdi;Gholami, Leila;Ghojazadeh, Morteza;Emadi, Naghmeh
    • Imaging Science in Dentistry
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    • v.52 no.2
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    • pp.141-153
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    • 2022
  • Purpose: This study aimed to identify the prevalence and extension of the anterior loop (AL) of the mental nerve in different populations and according to different cone-beam computed tomography (CBCT) imaging settings. Materials and Methods: Medline/PubMed, Embase, Scopus, Web of Science, and ProQuest were searched. The main inclusion criterion was ALs evaluated in CBCT images. The quality of studies was assessed with the Joanna Briggs Institute risk of bias checklist. Subgroup analyses were conducted for sex, side, continent, voxel size, field of view, and type of CBCT-reconstruction images with a random-effects model. Results: Sixty-three studies with 13,743 participants (27,075 hemimandibles) were included. An AL was found in 40.6% (95% CI: 32.8%-48.9%, P<0.05) of participants and 36.0% (95% CI: 27.5%-45.5%, P<0.05) of hemimandibles, in 34.9% (95% CI: 25.1%-46.2%, P<0.05) of males and 34.5% (95% CI: 23.5%-47.4%, P<0.05) of females. The average length of ALs was 2.39 mm (95% CI: 2.07-2.70 mm, P<0.05). Their extension was 2.13 mm (95% CI: 1.54-2.73 mm, P<0.05) in males and 1.85 mm (95% CI: 1.35-2.36 mm, P<0.05) in females. Significant differences were observed regarding the prevalence and length of ALs among continents and for its measured length on different CBCT-reconstruction images, but not between other subgroups. Conclusion: AL was a relatively common finding. The voxel size and fields of view of CBCT devices were adequate for assessing AL; however, a 2-mm safety margin from anatomical structures(such as the AL) could be recommended to be considered when using CBCT imaging.

Number of implants for mandibular implant overdentures: a systematic review

  • Lee, Jeong-Yol;Kim, Ha-Young;Shin, Sang-Wan;Bryant, S. Ross
    • The Journal of Advanced Prosthodontics
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    • v.4 no.4
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    • pp.204-209
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    • 2012
  • PURPOSE. The aim of this systematic review is to address treatment outcomes of Mandibular implant overdentures relative to implant survival rate, maintenance and complications, and patient satisfaction. MATERIALS AND METHODS. A systematic literature search was conducted by a PubMed search strategy and hand-searching of relevant journals from included studies. Randomized Clinical Trials (RCT) and comparative clinical trial studies on mandibular implant overdentures until August, 2010 were selected. Eleven studies from 1098 studies were finally selected and data were analyzed relative to number of implants. RESULTS. Six studies presented the data of the implant survival rate which ranged from 95% to 100% for 2 and 4 implant group and from 81.8% to 96.1% for 1 and 2 implant group. One study, which statistically compared implant survival rate showed no significant differences relative to the number of implants. The most common type of prosthetic maintenance and complications were replacement or reattaching of loose clips for 2 and 4 implant group, and denture repair due to the fracture around an implant for 1 and 2 implant groups. Most studies showed no significant differences in the rate of prosthetic maintenance and complication, and patient satisfaction regardless the number of implants. CONCLUSION. The implant survival rate of mandibular overdentures is high regardless of the number of implants. Denture maintenance is likely not inflenced substantially by the number of implants and patient satisfaction is typically high again regardless os the number of implants.

Industrial Applications of Rumen Microbes - Review -

  • Cheng, K.J.;Lee, S.S.;Bae, H.D.;Ha, J.K.
    • Asian-Australasian Journal of Animal Sciences
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    • v.12 no.1
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    • pp.84-92
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    • 1999
  • The rumen microbial ecosystem is coming to be recognized as a rich alternative source of genes for industrially useful enzymes. Recent advances in biotechnology are enabling development of novel strategies for effective delivery and enhancement of these gene products. One particularly promising avenue for industrial application of rumen enzymes is as feed supplements for nonruminant and ruminant animal diets. Increasing competition in the livestock industry has forced producers to cut costs by adopting new technologies aimed at increasing production efficiency. Cellulases, xylanases, ${\beta}$-glucanases, pectinases, and phytases have been shown to increase the efficiency of feedstuff utilization (e.g., degradation of cellulose, xylan and ${\beta}$-glucan) and to decrease pollutants (e.g., phytic acid). These enzymes enhance the availability of feed components to the animal and eliminate some of their naturally occurring antinutritional effects. In the past, the cost and inconvenience of enzyme production and delivery has hampered widespread application of this promising technology. Over the last decade, however, advances in recombinant DNA technology have significantly improved microbial production systems. Novel strategies for delivery and enhancement of genes and gene products from the rumen include expression of seed proteins, oleosin proteins in canola and transgenic animals secreting digestive enzymes from the pancreas. Thus, the biotechnological framework is in place to achieve substantial improvements in animal production through enzyme supplementation. On the other hand, the rumen ecosystem provides ongoing enrichment and natural selection of microbes adapted to specific conditions, and represents a virtually untapped resource of novel products such as enzymes, detoxificants and antibiotics.