Novel enhancement of interfacial interaction and properties in biodegradable polymer composites using green chemically treated spent coffee ground microfiller

This study investigates the potential of utilizing green chemically treated spent coffee grounds (SCGs) as micro biofiller reinforcement in Poly-3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV) biopolymer composites. The aim is to assess the impact of varying SCG concentrations (1 %, 3 %, 5 %, and 7 %) on the functional, thermal, mechanical properties and biodegradability of the resulting composites with a PHBV matrix. The samples were produced through melt compounding using a twin-screw extruder and compression molding. The findings indicate successful dispersion and distribution of SCGs microfiller into PHBV. Chemical treatment of SCG microfiller enhanced the interfacial bonding between the SCG and PHBV, evidenced by higher water contact angles of the biopolymer composites. Field Emission Scanning Electron Microscopy (FE-SEM) confirmed the successful interaction of treated SCG microfiller, contributing to enhanced mechanical characteristics. A two-way ANOVA was conducted for statistical analysis. Mass losses observed after burying the materials in natural soil indicated that the composites degraded faster than the pure PHBV polymer suggesting that both composites are biodegradable, particularly at high levels of spent coffee grounds (SCG). Despite the possibility of agglomeration at higher concentrations, SCG incorporation resulted in improved functional properties, positioning the green biopolymer composite as a promising material for sustainable packaging and diverse applications.

Later exposure to perches and nests reduces individual hens' occupancy of vertical space in an aviary and increases force of falls at night

Tiered aviaries are intended to improve laying hen welfare by providing resources that enable them to perform essential behaviors. However, hens must be able to navigate these complex systems efficiently and safely. This study investigated the influence of providing perches and nests starting at 17 or 25 wk of age (WOA) on hens' use of vertical space in an aviary at 36 and 54 WOA. Three treatments were applied to pullets raised in floor pens until 17 WOA (4 units/treatment; 100 hens/unit). Control (CON) pullets were placed into aviaries at 17 WOA. Floor (FLR) pullets were placed into aviaries at 25 WOA. Perches and nests were placed in enriched (ENR) pullets' floor pens at 17 WOA prior to moving ENR birds to aviaries at 25 WOA. Five focal hens/unit (n = 20 total hens/treatment) were fitted with accelerometers, and their diurnal movement (g) and frequency (n) and acceleration (g) of falls at night were recorded. Direct observation of focal hens was conducted for 6 min/hen at morning, midday, and evening for 3 consecutive days at 36 and 54 WOA, and location and time spent on vertical tiers were recorded. At 36 WOA, FLR hens spent more time on litter than CON and ENR, which spent more time in the top tier (all P ≤ 0.05). ENR hens exhibited higher vertical movement than CON and FLR hens (0.8, 0.6, and 0.3 g; P = 0.003). CON hens fell most often at night (16 vs. 9 FLR and 5 ENR), whereas FLR hens had higher acceleration and calculated collision force than CON and ENR hens during falls (0.8, 0.5, 0.3 g and 15, 10, 5 N, respectively; P ≤ 0.05). At 54 WOA, hens' movement and vertical distribution were similar across treatments. Delaying birds' access to perches and nests until 25 WOA impacted their movement, vertical space use, and falls at night for at least 10 wk. However, providing perches and nests at 17 WOA, even in floor pens, considerably mitigated such impacts.

Pulmonary function of workers exposed to ammonia: a study in the Eastern Province of Saudi Arabia

To determine the effect of chronic exposure to ammonia on pulmonary function among ammonia workers, 77 workers were randomly selected from an ammonia factory in the Eastern Province of Saudi Arabia and 355 were selected as controls from the administrative staffs of four industrial groups in Eastern Province. Spirometry was carried out and FEV1, FVC, and FEV1/FVC% were calculated. The ammonia level in the working environment was determined spectrophotometrically. 30% of the air samples had ammonia concentrations that exceeded the threshold limit value. Significant reductions in FEV1 % predicted and FVC % predicted were observed in ammonia workers exposed to higher cumulative ammonia levels (above 50 mg/m3-years). FEV1% predicted and FEV1/FVC% were significantly lower in symptomatic than in asymptomatic workers in the exposed group. These findings may raise the possibility that exposure to a high cumulative ammonia level produces a combined restrictive/obstructive ventilatory defect.

Post-shift changes in pulmonary function in a cement factory in eastern Saudi Arabia

This cross-sectional study was conducted in 1992 in the oldest of three Portland cement producing factories in Eastern Saudi Arabia. The respirable dust level was in excess of the recommended ACGIH level in all sections. Spirometry was done for 149 cement workers and 348 controls, using a Vitalograph spirometer. FEV1, FVC, FEV1/FVC% and FEF25-75% were calculated and corrected to BTPS. A significantly higher post-shift reduction FEV1, FEV1/FVC% and FEF25-75% was observed in the exposed subjects. Multiple regression analysis showed a significant relationship between post-shift changes and exposure to cement dust but failed to support any relationship with smoking. These findings may indicate an increase in the bronchial muscle tone leading to some degree of bronchoconstriction as a result of an irritant effect induced by the acute exposure to cement dust.

Bronchial asthma in two chemical fertilizer producing factories in eastern Saudi Arabia

SETTING

Two urea fertilizer producing factories in Saudi Arabia.

OBJECTIVE

To determine the prevalence of respiratory symptoms and diseases in employees exposed to ammonia gas.

DESIGN

A cross-sectional study involving 161 exposed subjects and 355 controls. All completed a respiratory symptoms questionnaire, with additional questions on present and past occupations. Ammonia concentrations were measured in the different sections of the factories.

RESULTS

The ammonia levels in factory B were well below the threshold limit value (TLV) (range 0.02-7.0 mg/m3 of air). In factory A the range was 2.0-130.4 mg/m3. The control and exposed groups were comparable with respect to their smoking habits. The exposed subjects in factory A had significantly higher relative risks (RR) for all respiratory symptoms; the same was true for haemoptysis (RR: 4.1, 95% confidence interval: 1.63-10.28). Bronchial asthma, chronic bronchitis, and a combined diagnosis were significantly higher among those exposed to high cumulative ammonia levels. However, in the logistic regression analysis ammonia concentration was significantly related to cough, phlegm, shortness of breath with wheezing and bronchial asthma.

CONCLUSION

Exposure to ammonia gas in the workplace is significantly associated with increase in respiratory symptoms and bronchial asthma. Re-engineering measures to lower the levels of ammonia in factory A are strongly recommended. The affected employees should be removed from further exposure and followed up.

Standardization of different spirometers

This study was designed to compare spirometers used for human testing and to determine whether the results obtained by different spirometers meeting the American Thoracic Society (ATS) requirements are interchangeable. Water-sealed spirometer (Harvard), dry bellow wedge spirometer (Vitalograph) and computerized pneumotachograph (Gould), all of them satisfying the ATS recommendations were compared. Forced vital capacity (FVC), forced expiratory volume in the first second (FEV1), forced expired flow between 25 and 75% of FVC (FEF 25-75%) and 100 FEV1/FVC (FEV1%) were selected for comparative analysis. Measurements of these parameters were carried out on a total of 40 healthy volunteers of mixed nationalities. The Vitalograph values for FVC, FEV1 and FEV1% were significantly higher than those of the water-sealed spirometer (Harvard), but were closely similar to the values obtained by the Gould computerized pneumotachograph. Our results thus do not support the interchangeability of different spirometers and stress the importance of biological standardization of spirometers against each other.

Origin of crystalloid inclusions in macrophages II: evidence for derivation from eosinophil granulocyte breakdown

Peritoneal macrophages were studied by light and electron microscopy in normal adult mice 24 h after 3 daily injections of preparations of leucocytes and platelets. Crystalloid inclusions, similar to those seen in bone marrow macrophages of normal adult mice and in man, were occasionally observed in peritoneal macrophages after administration buffy-coat white cells but not after platelets. They were much more frequently seen following the ingestion of eosinophil-rich granulocytes and were almost always associated with secondary lysosomes. Energy-dispersive analysis of X-ray provided further evidence that both crystalloid inclusions and lysosomes originated from the injected granulocytes. These observations suggest that crystalloid inclusions in marrow macrophages are derived from granulocyte breakdown and that in this respect eosinophil granulocytes are of prime importance.

Origin of crystalloid inclusions in macrophages I: studies of peritoneal macrophages after erythrocyte ingestion

In an attempt to investigate the origin of crystalloid inclusions present in bone-marrow macrophages of normal adult mice and in man, murine peritoneal macrophages (which normally do not contain inclusions of this nature) were studied by light and electron microscopy 24 h after 3 daily injections of various preparations of erythrocytes. The preparations included mouse erythrocytes with and without pretreatment with collagenase, human erythrocytes and human-erythrocyte ghosts. Crystalloid inclusions were only rarely seen in the peritoneal macrophages in these circumstances. The results offered little support for the idea that crystalloid inclusions are derived from the breakdown of erythrocytes.