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51.
52.
The epidemiology of whooping cough (pertussis) remains enigmatic. A leading cause of infant mortality globally, its resurgence in several developed nations--despite the availability and use of vaccines for many decades--has caused alarm. We combined data from a singular natural experiment and a detailed contact network study to show that age-specific contact patterns alone can explain shifts in prevalence and age-stratified incidence in the vaccine era. The practical implications of our results are notable: Ignoring age-structured contacts is likely to result in misinterpretation of epidemiological data and potentially costly policy missteps. 相似文献
53.
Sayed Zia Mohammadi Tahereh Rohani Leila Bahadori 《Communications in Soil Science and Plant Analysis》2017,48(11):1359-1368
In the present work, magnetic iron oxide nanoparticles (MIONPs) coated with sodium dodecyl sulfate (SDS) and modified with 1-(2-pyridylazo)-2-naphthol (PAN) as a new nanoparticle were prepared and used as an adsorbent for the extraction and preconcentration of copper ions. After adsorption, copper ions were desorbed with nitric acid (HNO3), followed by determination with flame atomic absorption spectrometry (FAAS). The extraction conditions0. were investigated systematically. The linear range 3.0–500.0 ng mL?1 and the detection limit of 0.6 ng mL?1 were obtained. The relative standard deviation (RSD) of the method for seven replicate determinations of 0.1 µg mL?1 of Cu(II) was 2.2%. The method was applied for the determination of Cu(II) in different water samples with good trueness. The accuracy was also evaluated through analyses of a certified reference material (CRM TMDW-500). 相似文献
54.
Ultrasound during mid‐gestation: Agreement with physical foetal and placental measurements and use in predicting gestational age in sheep 下载免费PDF全文
AK Jones RE Gately KK McFadden ML Hoffman SM Pillai SA Zinn KE Govoni SA Reed 《Reproduction in domestic animals》2017,52(4):649-654
To determine the effects of poor maternal nutrition and litter size on foetal growth during mid‐gestation, pregnant ewes (n = 82) were fed 100%, 60% or 140% of NRC TDN beginning at day 30.2 ± 0.2 of gestation. Transabdominal ultrasound was performed weekly between day 46.0 ± 0.4 and 86.0 ± 0.7 to monitor foetal heart width (HW), umbilical diameter (UMB), rib width (RW) and placentome outer (OD) and inner diameter (ID). Data were analysed with repeated‐measures using the mixed procedure for effects of maternal diet, litter size and gestation, and equations predictive of gestational age were generated using the regression procedure. To determine the agreement of ultrasound measurement and actual size, ewes (n = 20–21) were euthanized at day 45 or 90 to obtain corresponding postmortem measurements for Bland–Altman analysis. The HW, UMB and placentome OD and ID increased with gestation (p < .0001) but were unaffected by maternal diet or litter size (p ≥ .12). Ultrasound underestimated postmortem measurements of HW (14.8%), UMB (7.3%), placentome OD (4.5%) and ID (37.3%) at day 90 of gestation. Ultrasound underestimated RW at day 45 (7.7%) but overestimated RW (23.8%) at day 90, indicating inconsistent bias when reporting RW by ultrasound. Combining the HW, UMB, RW and placentome OD generated the strongest equation predictive of gestational age (R2 = .91). These findings indicate that during mid‐gestation, maternal diet or litter size did not affect HW, UMB or placentome diameters and these factors can be used to estimate gestational age. 相似文献
55.
Lulu Rayhan Khushi SM Rubaiot Abdullah Sanjoy Saha Mohammad Raqibul Hasan Siddique 《Southern Forests》2019,81(1):45-48
Gmelina arborea Roxb. is a fast-growing, deciduous tree species native to Bangladesh. It has been widely planted since 1992 for commercial production of pulpwood in hilly areas of Bangladesh. The purpose of this study was to derive well-fitting allometric models for estimation of aboveground biomass, and carbon and nutrient (nitrogen, phosphorus and potassium) stocks in G. arborea to ensure sustainable production and management of this species. Eight linear models with 64 regression equations were tested for estimation of aboveground biomass, carbon and nutrient stocks in different parts (leaves, branches, bark and stem) of the plant. The best-fitting allometric models were selected in accordance with various relevant statistical criteria. 相似文献
56.
A major concern in solvent extraction processes is the loss of extractant into the aqueous phase due to its slight solubility
in the aqueous phase. Similarly, in membrane extraction processes, extractant loss through extractant leakage from the membrane
into the aqueous phase is also a concern. Several published membrane extraction studies using Aliquat 336 as the extractant,
have expressed this concern, but none has studied extractant leakage quantitatively. It is the authors’ opinion that the extractant
leakage should be considered as a technical parameter of a membrane. In our laboratory active progress has been made in using
Aliquat 336 ‘entangled’ into the polymer membranes to remove heavy metal ions from wastewater samples. In this work, we studied
the loss of Aliquat 336 from the point of view of its solubility in aqueous solutions. The results showed that the solubilities
of Aliquat 336 in an aqueous phase acidified with 2 M HCl is about 0.1 g/100 m/ of the solution. This figure provides a useful
guideline for evaluating the leakage of the Aliquat 336 extractant from the membranes. 相似文献
57.
Retention of aging ewes is a strategy producers may use to maintain or increase flock size. Older ewes can have a higher risk of mortality and health issues, but these may be minimised with early intervention and culling. This retrospective study examined the incidence and causes of mortality and culling in a flock of Merino ewes as they aged from 4.5 to 5.5 until 9.5 to 10.5 years. The annual rate of ewe mortality ranged from 6.2% to 9.9%, with lambing complications being the major source of reported loss. Annual culling rates ranged from 1.6% to 42.8%, the larger rates reflecting opportunistic replacement with younger ewes rather than essential culling to maintain welfare and productivity. The major reasons for culling were low condition score, worn or missing teeth or faulty udders. The incidence of other faults was low. Only 18.3% of ewes remained when aged 9.5–10.5 years and these were fertile (89% pregnant) with a high proportion of multiple fetuses (52%) in their final year, although fleece weight had declined. Younger ewes born in 2004/2005 tended to have lower annual mortality rates than the aged ewes, but 8%–12% were still culled annually. It is concluded that an annual inspection pre-joining of all ewes and preventative culling for health issues is necessary to minimise any increase in mortality and risk to ewe welfare from retaining aging ewes. More frequent inspection will be required as potential health issues develop during the year, as these may not be evident pre-joining. 相似文献
58.
CC Kneipp AM Rose J Robson R Malik AT Deutscher AK Wiethoelter SM Mor 《Australian veterinary journal》2023,101(4):133-141
Brucella suis is an emerging, zoonotic disease predominantly affecting dogs and humans that engage in feral pig hunting in Australia and other countries. Although B. suis infection in dogs shares some clinical similarities to the host-adapted species (B. canis), B. suis remains an incompletely understood pathogen in dogs with limited published data on its pathogenesis and clinical features. This case series describes the presentations, diagnosis, and clinical management of B. suis infection in three dogs: (1) a bitch with dystocia, abortion and mastitis; (2) an entire male dog with septic arthritis and presumptive osteomyelitis; and (3) a castrated male dog with lymphadenitis. Unique features of these cases are reported including the first documented detection of B. suis from milk and isolation from lymph nodes of canine patients, as well as the follow-up of pups born to a B. suis-infected bitch. Consistent with previous reports, all three dogs showed a favourable clinical response to combination antibiotic therapy with rifampicin and doxycycline. Individually tailored drug regimens were required based on the clinical presentation and other factors, including owner expectations and compliance with therapy as well as a zoonotic risk assessment (generally considered low, except around time of whelping). The authors include their recommendations for the clinical management of dogs that are at-risk or seropositive for B. suis with or without clinical signs or laboratory-confirmed infection. 相似文献
59.
Copper-Catalyzed Oxidation of Alcohols to Aldehydes and Ketones: An Efficient, Aerobic Alternative 总被引:1,自引:0,他引:1
An efficient, copper-based catalyst has been discovered that oxidizes a wide range of alcohols into aldehydes and ketones under mild conditions. This catalytic system utilizes oxygen or air as the ultimate, stoichiometric oxidant, producing water as the only by-product. 相似文献
60.
SM Hughes 《New Zealand veterinary journal》2013,61(5):242-247
CASE HISTORY: A 6.2 kg, 8-year-old, spayed female Australian Terrier was presented with weight loss, inappetence, lethargy and a 2-day history of intermittent vomiting. CLINICAL FINDINGS: The dog had cranial abdominal pain and there was melaena present on digital rectal examination. Haematology revealed a marked, acute leucogram. DIAGNOSIS AND TREATMENT: Fasting serum gastrin levels were markedly elevated and gastrinoma was suspected. Treatment was initiated with omeprazole, ranitidine and sucralfate. The dog remained clinically normal for 26 months, at which time exploratory surgery was undertaken and the dog subsequently euthanised due to extensive metastases. Histopathology and immunocytochemistry confirmed the diagnosis of metastatic gastrinoma. CLINICAL RELEVANCE: This is a rare condition infrequently reported. Although the number of cases treated with omeprazole are too few to draw firm conclusions, it would appear that proton pump inhibitors are useful and should be considered for cases of gastrinoma managed medically. Long-term prognosis is poor, and survival times range from 1 to 147 weeks. Many treatment options are discussed in the medical literature though not all are feasible in veterinary patients. 相似文献