Laboratory Studies on the Bionomics of the Rat Fleas, Xenopsylla brasiliensis, Baker and X. cheopis, Roths

1947 ◽  
Vol 38 (3) ◽  
pp. 389-404 ◽  
Author(s):  
E. B. Edney

1. The paper describes work carried out to find the causes of certain discrepancies in the results of longevity experiments on rat-fleas.2. The following factors were found to reduce significantly the survival period of unfed adult fleas:—Rearing larvae together rather than in separate tubes; Parent fleas over 11 days old; Using very fine rather than coarse sand as a matrix for larval food; Drying the blood for larval food by baking rather than in a vacuum over sulphuric acid at room temperature.3. The following factors were found to have no significant effect upon adult longevity:—Contamination of larval food by mice and their droppings;Presence or absence of adult flea faeces in larval food.4. The effect upon the weight of larvae and the duration of the larval period of some of the above-mentioned factors is described. The female larval period is shown to be shorter than that of the male under all conditions used.5. It is confirmed that there is no significant difference between the longevity of male and female adults which have fed once or not at all, and that females which have fed frequently before starvation live longer than males.6. Well developed, unfed, laboratory-bred adult fleas live longer than those which have fed once before starvation, and the latter live longer than those which have fed several times.7. There is some evidence that unfed wild-caught fleas live longer than wildcaught fleas which have fed, but this needs confirmation.8. All the available information regarding factors affecting adult longevity is summarised in a table.

Author(s):  
Nguyễn Thị Hồng Thu ◽  
Đặng Minh Nhật ◽  
Nguyễn Hoàng Dung

Sugar palm (Arenga pinnata) is a feather palm native to tropical Asia. In Vietnam, it is named Búng Báng or Đoác and grown only on the highlands in the central or northern part of Vietnam. It is utilized for many purposes, especially for Ta Vat wine production - a characteristic and unique product of Co Tu ethnic minority. However, because of the natural fermentation used in the production, the product quality is inconsistent. The purpose of this study was to examine a new procedure of using palm sap for making Ta Vat wine. Some characteristics of the sap, which was collected at Nam Giang district, Quang Nam province are determined, proving the potential of the sap for making wine product. The quality of sap changes quickly at room temperature. At low temperature (4 - 60C), the changes in sap quality are apparently slower. Examining some factors affecting its quality during the wine fermentation process, we determined the best parameters for the fermentation process as follows: inoculum size of 3% with cell density of about 1x108 cells/ml, the addition of the extract from the bark of Ceylon ironwood (Mesua ferrea L.) 4%. Keywords: Arenga pinnata, sap, Ceylon ironwood bark, Mesua ferrea L., wine fermentation.


2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
V.L Malavasi ◽  
E Fantecchi ◽  
V Tordoni ◽  
L Melara ◽  
A Barbieri ◽  
...  

Abstract Background Natural history of atrial fibrillation (AF) shows a progression of arrhythmia from non-permanent to permanent AF. Permanent AF was found associated with a worse prognosis than non-permanent one. Aim To assess the factors associated with progression to permanent AF in an unselected population of AF patients with non-permanent AF. Methods In this prospective study we enrolled in- as well as out-patients with non-permanent AF and age ≥18 years, with at least one episode of ECG-documented AF within 1 year. The patients were followed-up at 1 month and every 6 months thereafter. Results Out of 523 patients, 314 (60%) were in non-permanent AF (80 [25.5%] paroxysmal AF, 165 [52.5%] persistent AF, 69 [2%] first diagnosed AF), mostly male (188, 59.9%), median age 71 years (IQ range 62–77), median CHA2DS2VASc 3 (1–4), median HATCH score 1 (1–2). After a median follow-up of 701 (IQ range 437–902) days, 66 patients (21%) showed permanent AF. CHA2DS2VASc and HATCH scores were incrementally associated to progression to permanent AF (CHA2DS2VASc χ2 p=0.001; HATCH χ2 p=0.017; p for trend CHA2DS2VASc <0.001, HATCH p=0.001). At multivariable Cox proportional hazard regression the following variables were significantly associated with AF progression: age (hazard ratio [HR] 1.041; 95% CI: 1.004–1.079; p=0.028), at least moderate left atrial (LA) enlargement (>42 ml/m2) (HR 2.092; 95% CI: 1.132–3.866; p=0.018), antiarrhythmics drugs after the enrollment (HR 0.087; 95% CI: 0.011–0.662; p=0.018), EHRA score >2 (HR 0.351; 95% CI: 0.158–0.779; p=0.010) and Valvular HD (HR 2.161; 95% CI: 1.057–4.420; p=0.035). Adding LA dilation to HATCH score (HATCH-LA) and assigning 2 points based on multivariable Cox regression, HATCH-LA was statistically better in ROC curves in prediction of AF progression vs HATCH score (area under the curve 0.695 vs 0.636; DeLong p=0.0225). Survival-free curves on freedom from permanent AF using as discriminator HATCH-LA score ≤2 vs >2 led to a statistically significant difference (χ2=16.080 p<0.001), but the same was not found for HATCH score (χ2 =3.099; p=0.078). Conclusions In patients without permanent AF, progression of AF was independentely related to age, LA dilation, AF symptoms severity, antiarrhythmic drugs and Valvular HD. HATCH score predicted AF progression and adding to it LA dilation (at least moderate) improved patients stratification for the risk of evolution to permanent AF. Funding Acknowledgement Type of funding source: None


2021 ◽  
pp. 1-7
Author(s):  
Gamze Aytaş ◽  
Rümeyza Kazancıoğlu ◽  
Ömer C. Elçioğlu ◽  
Meltem Gürsu ◽  
A. Serra Artan ◽  
...  

<b><i>Introduction:</i></b> Orthostatic hypotension (OH) affects 5–20% of the population. Our study investigates the presence of OH in diabetic nephropathy (DNP) patients and the factors affecting OH in comparison with nondiabetic chronic kidney disease (NDCKD) patients. <b><i>Method:</i></b> Patients presented to the nephrology clinic, and those who consented were included in the study. DNP was defined by kidney biopsy and/or clinical criteria. NDCKD patients of the same sex, age, and eGFR were matched to DNP patients. Demographic parameters and medications were obtained from the records. OH was determined by Mayo clinic criteria. The same researcher used an electronic device to measure blood pressure (BP). All samples were taken and analyzed the same day for biochemical and hematologic parameters and albuminuria. <b><i>Results:</i></b> 112 (51 F, 61 M, mean age: 62.56 ± 9.35 years) DNP and 94 (40 F, 54 M, mean age: 62.23 ± 10.08 years) NDCKD patients were included. There was no significant difference between DNP and NDCKD groups in terms of OH prevalence (70.5 vs. 61.7%, <i>p</i> = 0.181). Male patients had significantly higher OH prevalence than female patients (74.7 vs. 60.0%, <i>p</i> = 0.026). There was no significant difference in change in systolic BP between the groups (24.00 [10.00–32.00] mm Hg vs. 24.00 [13.75–30.25] mm Hg, <i>p</i> = 0.797), but the change in diastolic BP was significantly higher in the DNP group (8.00 [2.00–13.00] mm Hg vs. 6.00 [2.00–9.00] mm Hg, <i>p</i> = 0.025). In the DNP group, patients with OH had significantly higher uric acid levels than those without OH (7.18 ± 1.55 vs. 6.36 ± 1.65 mg/dL, <i>p</i> = 0.017). And, 73.7% of patients on calcium channel blockers developed OH (<i>p</i> = 0.015), and OH developed in 80.6% of 36 patients on alpha-blockers (<i>p</i> = 0.049). <b><i>Conclusion:</i></b> OH prevalence is very high in CKD, and etiology of CKD does not have a statistically significant effect on the frequency of OH, despite a difference that could be meaningful clinically. Therefore, patients with CKD are checked for OH, with or without concurrent diabetes mellitus. Evaluation of postural BP changes should be a part of nephrology practice.


2005 ◽  
Vol 86 (12) ◽  
pp. 3419-3424 ◽  
Author(s):  
Constanze Yue ◽  
Elke Genersch

Deformed wing virus (DWV) is a honeybee viral pathogen either persisting as an inapparent infection or resulting in wing deformity. The occurrence of deformity is associated with the transmission of DWV through Varroa destructor during pupal stages. Such infections with DWV add to the pathology of V. destructor and play a major role in colony collapse in the course of varroosis. Using a recently developed RT-PCR protocol for the detection of DWV, individual bees and mites originating from hives differing in Varroa infestation levels and the occurrence of crippled bees were analysed. It was found that 100 % of both crippled and asymptomatic bees were positive for DWV. However, a significant difference in the spatial distribution of DWV between asymptomatic and crippled bees could be demonstrated: when analysing head, thorax and abdomen of crippled bees, all body parts were always strongly positive for viral sequences. In contrast, for asymptomatic bees viral sequences could be detected in RNA extracted from the thorax and/or abdomen but never in RNA extracted from the head. DWV replication was demonstrated in almost all DWV-positive body parts of infected bees. Analysing individual mites for the presence of DWV revealed that the percentage of DWV-positive mites differed between mite populations. In addition, it was demonstrated that DWV was able to replicate in some but not all mites. Interestingly, virus replication in mites was correlated with wing deformity. DWV was also detected in the larval food, implicating that in addition to transmission by V. destructor DWV is also transmitted by feeding.


2020 ◽  
Vol 45 (2) ◽  
pp. 7900-7915
Author(s):  
Mostakim Lahcen ◽  
Fetnassi Nidal ◽  
Ghamizi Mohamed

Measuring the phytodiversity and determining environmental factors affecting the abundance and distribution of riparian plants of Zat sub-basin in Morocco were carried out in this study. A hypothesis was tested whether there is any statistically significant difference in environmental parameters and plants communities among the Zat River and its tributaries. For this purpose, water quality parameters such as temperature, pH, salinity, electrical conductivity, Dissolved Oxygen, nitrate and phosphorus concentration, and riparian plants diversity were estimated at 17 stations along the Zat River and its tributaries during the periods (2018 and 2019). The Canonical Correspondence Analysis (CCA) and Pearson correlation were preformed to assess the relationship between environmental parameters, and the distribution and abundance of riparian plants inventoried. The presence of 113 species was recorded, distributed between 43 families and 97 genera, 9 of which were floating-leaved, 24 submerged, and 80 emergent plants. The rare and threatened species inventoried were represented by 7 taxa, whereas 6 species are reported as endemic. Raunkiaer classification showed a dominance of therophytes (38.39%) over the other groups. According to CCA, the abiotic parameters (DO, elevation, salinity and nitrate concentration) were statistically significant parameters governing the distribution and abundance of the riparian plants inventoried. The results obtained reveal the state of the riparian vegetation in the Zat subBasin, therefore we can consider them as a reliable component for the assessment of the ecological status of the aquatic environment.


PEDIATRICS ◽  
1950 ◽  
Vol 5 (4) ◽  
pp. 664-671
Author(s):  
B. M. KAGAN ◽  
M. NIERENBERG ◽  
D. GOLDBERG ◽  
A. MILZER

Table I summarizes most of the pertinent data in this report on the serum penicillin concentrations 12 and 24 hours after intramuscular injection of K penicillin G in peanut oil and beeswax, which is fluid at room temperature, and of three different procaine penicillin preparations. These three preparations are procaine penicillin G in sesame oil, procaine penicillin G in peanut oil with 2% aluminum monostearate, and procaine penicillin G in water with Na-carboxymethylcellulose. When they were given in a dosage of 8000 u./lb. to infants and children, weighing between 4.5 and 18.0 kg., there was no statistically significant difference in the serum levels obtained. A dosage schedule for these preparations is suggested for pediatric use. The aqueous preparation offers some advantages which are discussed. Experiences are reported which emphasize the necessity of avoiding intravenous administration of all these preparations.


2021 ◽  
Vol 6 (14) ◽  
pp. 1-7
Author(s):  
Emine Serap ÇAĞAN ◽  
Birsen KARACA SAYDAM ◽  
Sinem GÜLÜMSER ATEŞ ◽  
Rabia EKTİ GENÇ ◽  
Esin ÇEBER TURFAN

Introduction: The primary attachment figure is mostly defined as the mother, and studies focus on the mother. However, in many babies, basic attachment is just as good with the father as with the mother. It is seen that there are very few studies in the literature investigating the correlations of father-infant attachment relationships.. The aim of this study is to determine the father-infant attachment status and to determine the factors affecting attachment. Method: The population of the cross-sectional study consisted of the spouses of all puerperant women hospitalized in the Gynecology and Obstetrics Clinic between September 1, 2018 and October 1, 2018. The sample size consisted of 156 fathers who agreed to participate in the study. Father identification form and father-infant attachment scale were used to collect the study data. The analysis of the data obtained from the research was carried out on the computer using the SPSS 16.0 package program. Results: 156 fathers participated in the study. The mean age of the fathers is 33.64±6.49, and 38.5% of them have a bachelor's degree. 91.0% of fathers stated that they felt ready for fatherhood. The fathers' Father-Infant Attachment Scale mean score was 82.60±7.72 In the analysis, the difference between the variables and the total score of the scale was found to be statistically insignificant (p>0.05). Discussion and Conclusion: At the end of the study, the bonding process of fathers participating in the study with their babies and the factors affecting this process were evaluated and it was seen that the father-infant attachment scale mean scores of the fathers participating in the study were high and were similar to other studies. In addition, when the basic factors affecting father-infant attachment were compared with the attachment scale mean score, it was found that there was no statistically significant difference.


Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Mitch Kampmeyer ◽  
Clifton W Callaway

Recent research supports the use of cold IV fluid as a method for initiating therapeutic hypothermia in post-cardiac arrest resuscitation. However, prehospital care programs employing this treatment have encountered various difficulties. Barriers to prehospital induced hypothermia protocols include the lack of effective or economically reasonable methods to maintain cold saline in the field. Objective. Determine the time that a standard commercial cooler can maintain two 1-liter normal saline solution (NSS) bags below 4°C in 3 different environments. Methods. Environments simulating an ambulance compartment were created for the experiment. NSS temperatures were continuously recorded inside a standard commercial cooler with or without ice packs (IPs) under one of three scenarios: ambient room temperature (25°C) without (IPs), ambient room temperature with IPs and 50°C ambient temperature with IPs. Four trials under each condition were performed. Time to warm to 4°C was compared using Kaplan-Meier log rank test. Results. In a room temperature environment with IPs, the NSS warmed to 4°C in a mean interval of 29 hrs 53 mins versus in ambient room temperature without IPs (1 hr 21 mins) versus in constant hot environment of 50°C with IPs (10 hrs 50 mins). A significant difference was found between the three environments (log-rank =17.90, dF =2, p =0.0001). Conclusions. Low technology methods in the form of a cooler and IPs can provide cold NSS storage for longer than a full 24 hour shift in a room temperature ambulance. In hot ambient conditions, 4°C NSS can be maintained for nearly 11 hours using this method. This model exhibits an economical, easily deployable cold saline storage unit.


2006 ◽  
Vol 118 ◽  
pp. 479-484 ◽  
Author(s):  
Yong Hwan Kim ◽  
S.I. Kwun

This study investigated the microstructure and mechanical properties of the wide-gap region brazed with various powder mixing ratios of additive powder (IN738) to filler metal powder (DF4B). The wide-gap brazing process was carried out in a vacuum of 2×10-5 torr at 1230°C for 1 hr. The microstructure of the brazed region was analyzed by FESEM and AES. The wide-gap region brazed with 60wt.% IN738 additive powder and 40 wt.% DF 4B filler metal powder had a microstructure consisting of Ni solid solution + γ' and (Cr, W)2B. The fracture strength of the wide-gap region brazed with 60 wt.% IN738 additive and 40 wt.% DF 4B powder was as high as 832 MPa at room temperature. It was found that the (Cr, W)2B and pores in the brazed region are important microstructural factors affecting the mechanical properties of the wide-gap brazed region.


2005 ◽  
Vol 51 (10) ◽  
pp. 1823-1829 ◽  
Author(s):  
Nils G Morgenthaler ◽  
Joachim Struck ◽  
Christine Alonso ◽  
Andreas Bergmann

Abstract Background: Adrenomedullin (ADM) is a potent vasodilatory peptide, and circulating concentrations have been described for several disease states, including dysfunction of the cardiovascular system and sepsis. Reliable quantification has been hampered by the short half-life, the existence of a binding protein, and physical properties. Here we report the technical evaluation of an assay for midregional pro-ADM (MR-proADM) that does not have these problems. Methods: MR-proADM was measured in a sandwich immunoluminometric assay using 2 polyclonal antibodies to amino acids 45–92 of proADM. The reference interval was defined in EDTA plasma of 264 healthy individuals (117 male, 147 female), and increased MR-proADM concentrations were found in 95 patients with sepsis and 54 patients with cardiovascular disease. Results: The assay has an analytical detection limit of 0.08 nmol/L, and the interassay CV was &lt;20% for values &gt;0.12 nmol/L. The assay was linear on dilution with undisturbed recovery of the analyte. EDTA-, heparin-, and citrate-plasma samples were stable (&lt;20% loss of analyte) for at least 3 days at room temperature, 14 days at 4 °C, and 1 year at −20 °C. MR-proADM values followed a gaussian distribution in healthy individuals with a mean (SD) of 0.33 (0.07) nmol/L (range, 0.10–0.64 nmol/L), without significant difference between males or females. The correlation coefficient for MR-proADM vs age was 0.50 (P &lt;0.001). MR-proADM was significantly (P &lt;0.001) increased in patients with cardiovascular disease [median (range), 0.56 (0.08–3.9) nmol/L] and patients with sepsis [3.7 (0.72–25.4) nmol/L]. Conclusions: MR-proADM is stable in plasma of healthy individuals and patients. MR-proADM measurements may be useful for evaluating patients with sepsis, systemic inflammation, or heart failure.


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