Transition metal oxide (NiO,CuO, ZnO)-doped calcium oxide catalysts derived from eggshells for the transesterification of refined waste cooking oil

This paper reports the synthesis of new transition metal oxide-modified CaO catalysts derived from eggshells for the transesterification of refined waste cooking oil. CaO is a well-known base catalyst for transesterification. However, its moderate basicity and low surface area have restricted its catalytic performance. Therefore, a new attempt was made to modify the CaO catalyst with transition metal oxides, including Ni, Cu and Zn oxides, via simple wetness impregnation method. The catalytic performance of the resulting modified CaO-based catalysts was evaluated through the transesterification reaction using refined waste cooking oil. The results showed that the NiO/CaO(10 : 90)(ES) catalyst calcined at 700 °C, demonstrated being highly potential as a catalyst. It gave the highest biodiesel production (97.3%) at the optimum conditions of 1 : 18 oil-to-methanol molar ratio, 6 wt% catalyst loading and 180 minutes reaction time as verified by response surface methodology (RSM). The high catalytic activity of NiO/CaO(10 : 90)(ES)(700 °C) was attributed to its high basicity (8.5867 mmol g⁻¹) and relatively large surface area (7.1 m² g⁻¹). The acid value and free fatty acids of the biodiesel produced under optimal process conditions followed the EN 14214 and ASTM D6751 limit with 0.17 mg KOH per g (AV) and 0.09 mg KOH per g (FFA), respectively.

This paper reports the synthesis of new transition metal oxide-modified CaO catalysts derived from eggshells for the transesterification of refined waste cooking oil.     

Formalin-assisted training eyes for ophthalmic wet lab practice

The foundation of an ophthalmologists’ microsurgical career begins in the wet lab. Training on donor cadaveric, animal like goat or pig eyes provide the most realistic surgical environment, however, the availability of a donor’s eyes for practice is limited. This scarcity is further escalated in this current coronavirus disease 2019 pandemic where eye donations have decreased. Even among those eyes which find their way into the wet lab, quite a few would have collapsed significantly making training difficult. Therefore, we looked at ways to salvage these collapsed globes. We describe a novel way of salvaging the collapsed eyeballs by injecting formalin in slow boluses into the vitreous cavity. The longer maintenance of the globe integrity without necessitating repeated injections facilitates better quality of surgical training and optimal utilization of these eyes.     

The anatomical relationship between the sural nerve and small saphenous vein: An ultrasound study of healthy participants

Procedures involving the small saphenous vein (SSV) can result in sural nerve (SN) damage due to the proximity of the two structures. The relationship between the SN and SSV has previously been described in cadaveric studies with limited scope on surface landmarks. This study investigates the relationship between the SN and SSV in vivo through ultrasound. Transverse/short‐axis ultrasound scans of 128 legs (64 healthy participants) were taken by a single observer using a GE Logiq e ultrasound system with a 5–13 Hz linear transducer (GE Logiq 12L‐RS). The SN was identified and traced from the lateral malleolus to the popliteal fossa noting its course and proximity to the SSV. The distance between the SN and SSV was measured at points representing the distal 50% and 25% of the total leg length (the distance between the medial tibial condyle and the inferior edge of the medial malleolus). The SN and SSV were visualized in all participants regardless of BMI and atypical anatomical relationship were noted in 20.3%. The SN pierced the fascia in the distal 25.9% ± 5.3% of the total leg length. The distance between the SN and SSV was 4.06 ± 1.8 mm and 3.4 ± 1.4 mm in the distal 50% and 25% points of the total leg length, respectively. There was no significant effect of sex or body side. The SSV is a viable option for multiple vein harvest. Ultrasound visualization can be a beneficial tool for delineating variations of the SN in relation to SSV prior to surgery. Clin. Anat. 32:277–281, 2019. © 2018 Wiley Periodicals, Inc.     

Autochthonous spread of DENV-3 genotype III in Malaysia mitigated by pre-existing homotypic and heterotypic immunity

Dengue virus type 3 genotype III (DENV-3/III) is widely distributed in most dengue-endemic regions. It emerged in Malaysia in 2008 and autochthonously spread in the midst of endemic DENV-3/I circulation. The spread, however, was limited and the virus did not cause any major outbreak. Spatiotemporal distribution study of DENV-3 over the period between 2005 and 2011 revealed that dengue cases involving DENV-3/III occurred mostly in areas without pre-existing circulating DENV-3. Neutralisation assays performed using sera of patients with the respective infection showed that the DENV-3/III viruses can be effectively neutralised by sera of patients with DENV-3 infection (50% foci reduction neutralisation titres (FRNT₅₀) > 1300). Sera of patients with DENV-1 infection (FRNT₅₀ ⩾ 190), but not sera of patients with DENV-2 infection (FRNT₅₀ ⩽ 50), were also able to neutralise the virus. These findings highlight the possibility that the pre-existing homotypic DENV-3 and the cross-reacting heterotypic DENV-1 antibody responses could play a role in mitigating a major outbreak involving DENV-3/III in the Klang Valley, Malaysia.Key words: Arbovirus, dengue virus, immunity, infectious disease, Malaysia     

Neurological presentation of neuro-Beh?et's syndrome: clinical categories

In an attempt to categorize the diverse neurological manifestations of Beh?et's syndrome, a group of 10 patients was prospectively studied; the diagnosis of Beh?et's syndrome was not known in any of them prior to their neurological presentation. A reasonably clear distinction can be made to divide the manifestations into three general categories with some overlap. Category I includes patients with increased intracranial pressure with or without cerebral venous sinus thrombosis. Category II are those presenting with a stroke. Category III are those patients who present with spinal cord involvement and CSF pleocytosis. Brainstem involvement was noted independently of the group. In general, patients with Neuro-Beh?et's syndrome showed little ocular involvement. The course of the illness both in morbidity and mortality tended to be better in category I, and mortality was only seen in category II patients. In populations susceptible to the disease, the clinical categorisation proposed may alert the clinician to the possibility of neuro-Beh?et's syndrome whenever patients with pseudotumour cerebri, dural sinus thrombosis, stroke in the young, unexplained myelitis or possible multiple sclerosis are encountered.     

ICON rice seed treatment toxicity to crayfish (Procambarus clarkii) in experimental rice paddies

Outdoor pools (2.3 x 2.3 m) were used to simulate typical rice agricultural practices in Louisiana, USA, to evaluate the toxicity of ICON (active ingredient [a.i.] fipronil) and its degradates to crayfish (Procambarus clarkii). Six paddies were planted with seed treated with ICON 6.2 FS at an exaggerated application rate of 0.05 kg a.i./ha (recommended rate, 0.042 kg a.i./ha), simulating three rice-planting scenarios. Two reference paddies were planted with untreated seed. Crayfish were exposed to tail water within 24 to 48 h after seeding, simulating standard Louisiana agricultural and water management practices. At 50 d after planting, a separate group of crayfish was caged in situ for 14 d to evaluate toxicity. An additional 50 crayfish were added to two paddies approximately 100 d after rice planting and held for 29 weeks to evaluate bioaccumulation. Residues of fipronil and its degradates in water and soil were similar to residue concentrations measured from rice fields in Louisiana. Tail water from the treated paddies was not toxic to crayfish. The fipronil 96-h median lethal concentration (LC50) for adult crayfish was 180 microg/L, which would provide at least a sixfold safety factor between the maximum fipronil concentration in tail water and the crayfish LC50. In situ exposures of crayfish also were not toxic. Concentrations of fipronil and its degradates after 29 weeks of exposure were less than 5 microg/kg in crayfish tail muscle tissue. These results demonstrate that label instructions adequately protect crayfish in a rice-crayfish cropping scenario when ICON is applied at maximum application rates as a seed treatment.     

Overweight and obesity among patients attending a Nigerian oral surgery clinic: implications for oral surgical practice in Nigeria

Aim

To determine the prevalence of overweight and obesity among patients attending oral and maxillofacial outpatient clinic of the Lagos University Teaching Hospital, Nigeria; and discuss the clinical and surgical implications that obesity has on the delivery of oral and maxillofacial surgical and anaesthetic care.

Methods

Consecutive patients presenting to the oral and maxillofacial surgery outpatient clinic at the Lagos University Teaching Hospital, Nigeria over a 4-month period (May–August 2004) were screened for age, sex, height and weight. All of the patients were treated for dentoalveolar surgical procedures (routine and surgical extractions), incisional and excisional biopsies, and enucleation under local anaesthesia.

Results

The BMIs of the studied patients ranged from 16.7 to 39.8 kg/m², with a mean of 24.6 ± 4.5 kg/m². Prevalence of excess weight was 39.1%. Thirty-one (11.4%) patients were obese and 75 (27.7%) patients were overweight. A significant difference was observed in the BMIs of male and female patients (P=0.000). The age groups < 30 years had mean BMIs that were considered normal; whereas other age groups above 30 years had mean BMIs that were considered overweight. Prevalence of obesity increases with increasing age. Obese individuals were seen in all the age groups except those < 20 years.

Conculsions

The prevalence of excess weight (overweight and obesity) in patients presenting in the studied oral and maxillofacial outpatient setting was 39.1%. Oral and maxillofacial surgeon needs to be aware of obesity-/overweight-related medical and surgical issues and take them into consideration when treating these patients.