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51.
Chrysoperla carnea (Steph.) is a general predator reared in industrial scale. Different eggs of moth were used to rear C. carnea, but stabled moth colony needed expensive equipment and is costly. In this research, we surveyed appropriate diet to mass rearing. For this purpose, 100 same old (24H) eggs of C. carnea, separately, were selected randomly from the mass culture of C. carnea which was reared on the egg of flour moth Anagasta kuehniella (Zeller), artificial diet and semi-artificial diet under laboratory conditions (25 ± 5°C, 65 ± 5% RH and L–D: 16–8). These results showed reduction process ex (expectation of life table at age X) and the survival curve was convex (K-Strategy). Also Lx in appearing of adults that fed on egg of flour moth, artificial diet and semi-artificial diet were 0.76, 0.4 and 0.9 which implied that 24, 60 and 10% of cohort were dead before reaching adult stage. Eggs produced by each female were recorded daily until all females died. The parameters were estimated using Carey’s (1993) method. Gross (GRR) and net (R0) reproductive rates of predator on A. kuehniella, artificial diet and semi artificial diets were 225.5 ± 3.45, 72.4 ± 3.5, 267.8 ± 4.8 and 180.12 ± 2.3, 24.33 ± 4.3, 254.05+3.3 (female/female/generation), respectively. Mean generation time (T), Doubling time (DT), Intrinsic rate of increase (rm ) and Finite rate of increase (λ) of predator on A. kuehniella, artificial diet and semi artificial diet were 31.9 ± 0.71, 42.87 ± 0.45, 29.79 ± 0.57 (days); 4.27 ± 0.03, 9.36 ± 0.06, 3.74 ± 0.05 (days); 0.162 ± 0.001, 0.074 ± 0.003, 1.185 ± 0.002; and 1.175 ± 0.001, 1.076 ± 0.002, 1.203 ± 0.002 (female/female/day), respectively. This research indicated that semi-artificial diet is a suitable prey for the predator. 相似文献
52.
Diana E. Mitchell Chenkai Dai Mehdi A. Rahman Joong Ho Ahn Charles C. Della Santina Kathleen E. Cullen 《PloS one》2013,8(10)
The vestibular system detects motion of the head in space and in turn generates reflexes that are vital for our daily activities. The eye movements produced by the vestibulo-ocular reflex (VOR) play an essential role in stabilizing the visual axis (gaze), while vestibulo-spinal reflexes ensure the maintenance of head and body posture. The neuronal pathways from the vestibular periphery to the cervical spinal cord potentially serve a dual role, since they function to stabilize the head relative to inertial space and could thus contribute to gaze (eye-in-head + head-in-space) and posture stabilization. To date, however, the functional significance of vestibular-neck pathways in alert primates remains a matter of debate. Here we used a vestibular prosthesis to 1) quantify vestibularly-driven head movements in primates, and 2) assess whether these evoked head movements make a significant contribution to gaze as well as postural stabilization. We stimulated electrodes implanted in the horizontal semicircular canal of alert rhesus monkeys, and measured the head and eye movements evoked during a 100ms time period for which the contribution of longer latency voluntary inputs to the neck would be minimal. Our results show that prosthetic stimulation evoked significant head movements with latencies consistent with known vestibulo-spinal pathways. Furthermore, while the evoked head movements were substantially smaller than the coincidently evoked eye movements, they made a significant contribution to gaze stabilization, complementing the VOR to ensure that the appropriate gaze response is achieved. We speculate that analogous compensatory head movements will be evoked when implanted prosthetic devices are transitioned to human patients. 相似文献
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54.
Mehdi Dadkhah Mohammad Lagzian Glenn Borchardt 《Journal of cell communication and signaling》2017,11(2):181-185
In recent years, the academic world has been faced with much academic misconduct. Examples involve plagiarizing papers, manipulating data, and launching predatory or hijacked journals. The literature exposing these activities is growing exponentially, and so is the presentation of criteria or guidelines for counteracting the problem. Most of the research is focused on predatory or hijacked journal detection and providing suitable warnings. Overlooked in all this is the fact that papers published in these journals are questionable, but nevertheless show up in standard citation databases. We need some way to flag them so future researchers will be aware of their questionable nature and prevent their use in literature review. 相似文献
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57.
Moeini MM Kiani A Mikaeili E Shabankareh HK 《Biological trace element research》2011,144(1-3):529-537
Forty heifers at the late stage of gestation were randomly assigned into five groups. Heifers were balanced for age, weight, and time of calving in each group. Four and 2?weeks before expected time of calving, the heifers were injected with 0?ml (C), 10?ml (T1), 20?ml (T2), 30?ml (T3), and 40?ml (T4) Se and VE supplements, respectively. Each milliliter of the supplement contained of 0.5?mg Se as sodium selenite and 50?IU of dl-alpha-tocopheryl acetate. Blood samples were collected from the heifers 4?weeks before expected calving and at calving day and from the calves at birth and 7?days of age. The serum Se and immunoglobulin G (IgG) concentrations, white blood cell and differential leukocyte counts were measured. The Se concentrations in the sera of the heifers before the injections of Se and VE supplements were the same among the groups (P?>?0.05), but after calving were significantly increased in the treated heifers (P?0.05). Similarly, the serum Se levels of calves of the treated heifers were higher (P?0.05). The Se concentrations in the colostrums of the heifers were affected by treatments (P?0.05). Colostrum and daily milk productions at 8-week lactation were increased in treated heifers compared with the controls (P?0.05). Likewise, the milk somatic cell counts decreased in the treated heifers compared with the controls. The changes of the mean serum IgG levels did not differ among calves (P?>?0.05). The white blood cell counts were higher in calves of heifers in groups T3 and T4 compared with the control group at 7?days of age (P?0.05). 相似文献
58.
Nageshwar YV Sheelu G Shambhu RR Muluka H Mehdi N Malik MS Kamal A 《Bioprocess and biosystems engineering》2011,34(5):515-523
Microbial nitrilases are biocatalysts of interest and the enzyme produced using various inducers exhibits altered substrate
specificity, which is of great interest in bioprocess development. The aim of the present study is to investigate the nitrilase-producing
Alcaligenes faecalis MTCC 10757 (IICT-A3) for its ability to transform various nitriles in the presence of different inducers after optimization
of various parameters for maximum enzyme production and activity. The production of A. faecalis MTCC 10757 (IICT-A3) nitrilase was optimum with glucose (1.0%), acrylonitrile (0.1%) at pH 7.0. The nitrilase activity of
A. faecalis MTCC 10757 (IICT-A3) was optimum at 35 °C, pH 8.0 and the enzyme was stable up to 6 h at 50 °C. The nitrilase enzyme produced
using different inducers was investigated for substrate specificity. The enzyme hydrolyzed aliphatic, heterocyclic and aromatic
nitriles with different substitutions. Acrylonitrile was the most preferred substrate (~40 U) as well as inducer. Benzonitrile
was hydrolyzed with almost twofold higher relative activity than acrylonitrile when it was used as an inducer. The versatile
nitrilase-producing A. faecalis MTCC 10757 (IICT-A3) exhibits efficient conversion of both aliphatic and aromatic nitriles. The aromatic nitriles, which
show not much or no affinity towards nitrilase from A. faecalis, are hydrolyzed effectively with this nitrilase-producing organism. Studies are in progress to exploit this organism for
synthesis of industrially important compounds. 相似文献
59.
A total of 250 broilers in a completely randomized design selected to evaluate the effect of different levels of chromium (Cr) supplementation on performance, carcass traits and some blood parameters of heat-stressed broiler chicks. All birds were kept under heat stress temperature (33?±?3°C) and divided into five treatments groups. Each treatment consisted of five pens with 10 birds in each pen. The basal diets were supplemented with 0?ppb (control), 800?ppb Cr-L-Met (T(1)), 1,200?ppb Cr-L-Met (T(2)) or 800?ppb CrCl(3) (T(3)), and 1,200?ppb CrCl(3) (T(4)). The feed intake and body mass were measured at 10, 21, and 42?days of age. Blood samples were collected from two birds in each replicates to determine biological and hematological values at 28 and 42?days of age. There were no significant difference in mass gain and feed conversion of broilers that received Cr supplementations compared with controls. The serum glucose concentration decreased in broilers received organic chromium methionine supplements compared with other treatments groups. Slight but not significant increases were observed in serum high-density lipoprotein (HDL) concentration of treated groups than controls while the mean serum HDL concentration was significantly higher in T(2) group compared with control group. Serum low-density lipoprotein level decreased in broiler received organic Cr supplements (p?0.05). 相似文献
60.
Manoj K. Pandey Subash C. Gupta Deepkamal Karelia Patrick J. Gilhooley Mehdi Shakibaei Bharat B. Aggarwal 《Biotechnology advances》2018,36(6):1633-1648
Bone loss or osteoporosis, is a slow-progressing disease that results from dysregulation of pro-inflammatory cytokines. The FDA has approved number of drugs for bone loss prevention, nonetheless all are expensive and have multiple side effects. The nutraceuticals identified from dietary agents such as butein, cardamonin, coronarin D curcumin, diosgenin, embelin, gambogic acid, genistein, plumbagin, quercetin, reseveratrol, zerumbone and more, can modulate cell signaling pathways and reverse/slow down osteoporosis. Most of these nutraceuticals are inexpensive; show no side effect while still possessing anti-inflammatory properties. This review provides various mechanisms of osteoporosis and how nutraceuticals can potentially prevent the bone loss. 相似文献