scholarly journals Effect of Larval Density on Development of the Coconut Hispine Beetle,Brontispa longissima(Gestro) (Coleoptera: Chrysomelidae)

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Mika Murata ◽  
Dang Thi Dung ◽  
Shun-ichiro Takano ◽  
Ryoko Tabata Ichiki ◽  
Satoshi Nakamura

The coconut hispine beetle,Brontispa longissimashows, aggregation in the field. To elucidate the effect of aggregation on larval developmental aspects, we examined the effects of larval density on various aspects of larval development and on survival rates. Recently we found thatB. longissimawas divided into two monophyletic clades by genetic analysis. Therefore, we also compared the results between two populations, from Ishigaki, Japan (ISH) and Papua New Guinea (PNG), which were representative of the two monophyletic clades ofB. longissima. In both ISH and PNG, the larval developmental period was shorter and the survival rate higher with rearing under high-density conditions than under isolated conditions. Similarly, fewer instars were required before pupation under high-density conditions than under isolated conditions.Brontispa longissimatherefore developed better under high-density conditions, and the trends in the density effect were similar between two monophyletic clades.

2008 ◽  
Vol 98 (5) ◽  
pp. 431-436 ◽  
Author(s):  
A. Carron ◽  
L. Bichaud ◽  
N. Platz ◽  
D.J. Bicout

AbstractThe larval survival and development times of Aedes caspius (Diptera: Culicidae) were examined in the laboratory. These life history traits were estimated using life tables constructed for two populations, one of which had been subjected to a long-term larvicide control program. Traits were evaluated for eight different population densities. The effects of population, larval stage and larval density were investigated using a general linear model. Density was positively correlated with larval survival but did not affect development time. The fourth instar and pupae had the lowest larval survival rates. First and fourth instar larvae had the longest development times. These traits were not significantly different between the two populations. The effect of larvicide control on these traits is discussed.


1969 ◽  
Vol 101 (2) ◽  
pp. 128-132 ◽  
Author(s):  
Milan Trpiš ◽  
J. A. Shemanchuk

AbstractThe most suitable temperature for larval development of Aedes flavescens was found to be 20 °C. At this temperature 74% of the larvae pupated in 20 days. At 15 °C the developmental period was 42 days with a survival rate of 54%. At 25 °C the developmental period was 22 days but the survival rate dropped to 7%. At 10 °C the developmental period was 80 days with a survival rate of 6%. At 5 °C and 30 °C mortality was 100% in the first instar stage. Adult males emerged from the pupae in three days at 25 °C, two days earlier than the females.


2007 ◽  
Vol 34 (1) ◽  
pp. 125-145 ◽  
Author(s):  
Alan Sangster

This paper considers the printing of Pacioli's Summa de Arithmetica, Geometria, Proportioni et Proportionalita (Summa) in 1494. In particular, it attempts to answer the question, how many copies of Summa were printed in 1494? It does so through consideration of the printing process, the printer of Summa, the size of the book, survival rates of other “serious” books of the period, and the dates it contains revealing when parts of it were completed. It finds that more copies were published than was previously suggested, and that the survival rate of copies has probably as much to do with the manner in which it was treated once acquired as in the number of copies printed.


BMC Cancer ◽  
2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Chaiwat Tawarungruang ◽  
Narong Khuntikeo ◽  
Nittaya Chamadol ◽  
Vallop Laopaiboon ◽  
Jaruwan Thuanman ◽  
...  

Abstract Background Cholangiocarcinoma (CCA) has been categorized based on tumor location as intrahepatic (ICCA), perihilar (PCCA) or distal (DCCA), and based on the morphology of the tumor of the bile duct as mass forming (MF), periductal infiltrating (PI) or intraductal (ID). To date, there is limited evidence available regarding the survival of CCA among these different anatomical and morphological classifications. This study aimed to evaluate the survival rate and median survival time after curative surgery among CCA patients according to their anatomical and morphological classifications, and to determine the association between these classifications and survival. Methods This study included CCA patients who underwent curative surgery from the Cholangiocarcinoma Screening and Care Program (CASCAP), Northeast Thailand. The anatomical and morphological classifications were based on pathological findings after surgery. Survival rates of CCA and median survival time since the date of CCA surgery and 95% confidence intervals (CI) were calculated. Multiple cox regression was performed to evaluate factors associated with survival which were quantified by hazard ratios (HR) and their 95% CIs. Results Of the 746 CCA patients, 514 had died at the completion of the study which constituted 15,643.6 person-months of data recordings. The incidence rate was 3.3 per 100 patients per month (95% CI: 3.0–3.6), with median survival time of 17.8 months (95% CI: 15.4–20.2), and 5-year survival rate of 24.6% (95% CI: 20.7–28.6). The longest median survival time was 21.8 months (95% CI: 16.3–27.3) while the highest 5-year survival rate of 34.8% (95% CI: 23.8–46.0) occurred in the DCCA group. A combination of anatomical and morphological classifications, PCCA+ID, was associated with the longest median survival time of 40.5 months (95% CI: 17.9–63.0) and the highest 5-year survival rate of 42.6% (95% CI: 25.4–58.9). The ICCA+MF combination was associated with survival (adjusted HR: 1.45; 95% CI: 1.01–2.09; P = 0.013) compared to ICCA+ID patients. Conclusions Among patients receiving surgical treatment, those with PCCA+ID had the highest 5-year survival rate, which was higher than in groups classified by only anatomical characteristics. Additionally, the patients with ICCA+MF tended to have unfavorable surgical outcomes. Showed the highest survival association. Therefore, further investigations into CCA imaging should focus on patients with a combination of anatomical and morphological classifications.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Yong Yang ◽  
Huiting Hu ◽  
Mianyan Zeng ◽  
Hongxing Chu ◽  
Zekun Gan ◽  
...  

Abstract Background Few large-sample studies in China have focused on the early survival of dental implants. The present study aimed to report the early survival rates of implants and determine the related influencing factors. Methods All patients receiving dental implants at our institution between 2006 and 2017 were included. The endpoint of the study was early survival rates of implants, according to gender, age, maxilla/mandible, dental position, bone augmentation, bone augmentation category, immediate implant, submerged implant category, implant diameter, implant length, implant torque, and other related factors. Initially, SPSS22.0 was used for statistical analysis. The Chi-square test was used to screen all factors, and those with p < 0.05 were further introduced into a multiple logistic regression model to illustrate the risk factors for early survival rates of implants. Results In this study, we included 1078 cases (601 males and 477 females) with 2053 implants. After implantation, 1974 implants were retained, and the early survival rate was 96.15%. Patients aged 30–60 years (OR  2.392), with Class I bone quality (OR  3.689), bone augmentation (OR  1.742), immediate implantation (OR  3.509), and implant length < 10 mm (OR  2.972), were said to possess risk factors conducive to early survival rates. Conclusions The early survival rate of implants in our cohort exceeded 96%, with risk factors including age, tooth position, bone quality, implant length, bone augmentation surgery, and immediate implantation. When the above factors coexist, implant placement should be treated carefully.


2021 ◽  
Vol 14 (1) ◽  
Author(s):  
Nwamaka Oluchukwu Akpodiete ◽  
Frédéric Tripet

Abstract Background Malaria vector control approaches that rely on mosquito releases such as the sterile insect technique (SIT) and suppression or replacement strategies relying on genetically modified mosquitoes (GMM) depend on effective mass production of Anopheles mosquitoes. Anophelines typically require relatively clean larval rearing water, and water management techniques that minimise toxic ammonia are key to achieving optimal rearing conditions in small and large rearing facilities. Zeolites are extensively used in closed-system fish aquaculture to improve water quality and reduce water consumption, thanks to their selective adsorption of ammonia and toxic heavy metals. The many advantages of zeolites include low cost, abundance in many parts of the world and environmental friendliness. However, so far, their potential benefit for mosquito rearing has not been evaluated. Methods This study evaluated the independent effects of zeolite and daily water changes (to simulate a continuous flow system) on the rearing of An. coluzzii under two feed regimes (powder and slurry feed) and larval densities (200 and 400 larvae per tray). The duration of larval development, adult emergence success and phenotypic quality (body size) were recorded to assess the impact of water treatments on mosquito numbers, phenotypic quality and identification of optimal feeding regimes and larval density for the use of zeolite. Results Overall, mosquito emergence, duration of development and adult phenotypic quality were significantly better in treatments with daily water changes. In treatments without daily water changes, zeolite significantly improved water quality at the lower larval rearing density, resulting in higher mosquito emergence and shorter development time. At the lower larval rearing density, the adult phenotypic quality did not significantly differ between zeolite treatment without water changes and those with daily changes. Conclusions These results suggest that treating rearing water with zeolite can improve mosquito production in smaller facilities. Zeolite could also offer cost-effective and environmentally friendly solutions for water recycling management systems in larger production facilities. Further studies are needed to optimise and assess the costs and benefits of such applications to Anopheles gambiae (s.l.) mosquito-rearing programmes. Graphic abstract


Author(s):  
Fouad A. Sakr ◽  
Rana H. Bachir ◽  
Mazen J. El Sayed

Abstract Introduction: Early police transport (PT) of penetrating trauma patients has the potential to improve survival rates for trauma patients. There are no well-established guidelines for the transport of blunt trauma patients by PT currently. Study Objective: This study examines the association between the survival rate of blunt trauma patients and the transport modality (police versus ground ambulance). Methods: A retrospective, matched cohort study was conducted using the National Trauma Data Bank (NTDB). All blunt trauma patients transported by police to trauma centers were identified and matched (one-to-four) to patients transported by ground Emergency Medical Services (EMS) for analysis. Descriptive analysis was carried out. This was followed by comparing all patients’ characteristics and their survival rates in terms of the mode of transportation. Results: Out of the 2,469 patients with blunt injuries, EMS transported 1,846 patients and police transported 623 patients. Most patients were 16-64 years of age (86.2%) with a male predominance (82.5%). Fall (38.4%) was the most common mechanism of injury with majority of injuries involving the head and neck body part (64.8%). Fractures were the most common nature of injury (62.1%). The overall survival rate of adult blunt trauma patients was similar for both methods of transportation (99.2%; P = 1.000). Conclusion: In this study, adult blunt trauma patients transported by police had similar outcomes to those transported by EMS. As such, PT in trauma should be encouraged and protocolized to improve resource utilization and outcomes further.


2020 ◽  
Vol 9 (12) ◽  
pp. 3943
Author(s):  
João Caramês ◽  
Ana Catarina Pinto ◽  
Gonçalo Caramês ◽  
Helena Francisco ◽  
Joana Fialho ◽  
...  

This retrospective study evaluated the survival rate of short, sandblasted acid-etched surfaced implants with 6 and 8 mm lengths with at least 120 days of follow-up. Data concerning patient, implant and surgery characteristics were retrieved from clinical records. Sandblasted and acid-etched (SLA)-surfaced tissue-level 6 mm (TL6) or 8 mm (TL8) implants or bone-level tapered 8 mm (BLT8) implants were used. Absolute and relative frequency distributions were calculated for qualitative variables and mean values and standard deviations for quantitative variables. A Cox regression model was performed to verify whether type, length and/or width influence the implant survival. The cumulative implant survival rate was assessed by time-to-event analyses (Kaplan–Meier estimator). In all, 513 patients with a mean age of 58.00 ± 12.44 years received 1008 dental implants with a mean follow-up of 21.57 ± 10.77 months. Most implants (78.17%) presented a 4.1 mm diameter, and the most frequent indication was a partially edentulous arch (44.15%). The most frequent locations were the posterior mandible (53.97%) and the posterior maxilla (31.55%). No significant differences were found in survival rates between groups of type, length and width of implant with the cumulative rate being 97.7% ± 0.5%. Within the limitations of this study, the evaluated short implants are a predictable option with high survival rates during the follow-up without statistical differences between the appraised types, lengths and widths.


Genetics ◽  
1981 ◽  
Vol 98 (4) ◽  
pp. 849B-869
Author(s):  
Andrew G Clark ◽  
Marcus W Feldman

ABSTRACT The effects of larval density on components of fertility fitness were investigated with two mutant lines of Drosophila melanogaster. The differences in adult body weight, wing length, larval survivorship and development time verified that flies reared at high density were resource limited. Experimental results indicate that: (1) relative fecundities of both sexes show density-dependent effects, (2) there is a strong density effect on male and female mating success, and (3) in general, there is a reduction in fecundity differences between genotypes at high density. These results imply that it may be important to consider fertility in models of density-dependent natural selection.


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