App-Free Method for Visualization of Polymers in 3D and Augmented Reality

The rise of virtual and online education in recent years has led to the development and popularization of many online tools, notably three-dimensional (3D) models and augmented reality (AR), for visualizing various structures in chemical sciences. The majority of the developed tools focus on either small molecules or biological systems, as information regarding their structure can be easily accessed from online databases or obtained through relatively quick calculations. As such, due to a lack of crystallographic and theoretical data available for nonbiological macromolecules, there is a noticeable lack of accessible online tools for the visualization of polymers in 3D. Herein, using a few sample polymers, we showcase a workflow for the generation of 3D models using molecular dynamics and Blender. The 3D structures can then be hosted on p3d.in, where AR models can be generated automatically. Furthermore, the hosted 3D models can then be shared via quick response (QR) codes and used in various settings without the need to download any applications.

Low-Cost Turbidity Sensor to Determine Eutrophication in Water Bodies

Eutrophication is the excessive growth of algae in water bodies that causes biodiversity loss, reducing water quality and attractiveness to people. This is an important problem in water bodies. In this paper, we propose a low-cost sensor to monitor eutrophication in concentrations between 0 to 200 mg/L and in different mixtures of sediment and algae (0, 20, 40, 60, 80, and 100% algae, the rest are sediment). We use two light sources (infrared and RGB LED) and two photoreceptors at 90° and 180° of the light sources. The system has a microcontroller (M5stacks) that powers the light sources and obtains the signal received by the photoreceptors. In addition, the microcontroller is responsible for sending information and generating alerts. Our results show that the use of infrared light at 90° can determine the turbidity with an error of 7.45% in NTU readings higher than 2.73 NTUs, and the use of infrared light at 180° can measure the solid concentration with an error of 11.40%. According to the determination of the % of algae, the use of a neural network has a precision of 89.3% in the classification, and the determination of the mg/L of algae in water has an error of 17.95%.

Distribution of Order Parameter in Solids under High Pressure Torsion

Severe plastic deformation (SPD) can lead to various phase transformations. High-pressure torsion (HPT) is one of the most important variants of SPD. In principle, HPT can continue almost indefinitely long, as long as the plungers are not destroyed. However, the number of defects in a material during HPT deformation cannot increase indefinitely. When the rate of defects production becomes equal to the rate of their annihilation, a steady state or dynamic equilibrium is reached. Unexplored is the issue of establishing equilibrium at the initial stage of plunger torsion, when there is an angular acceleration. The parameters of the steady state are described here using the idea of an order parameter in solids in the framework of Landau phenomenological theory and the Landau-Khalatnikov equation.

Analyzing Discrepancies in Chemical-Shift Predictions of Solid Pyridinium Fumarates

Highly accurate chemical-shift predictions in molecular solids are behind the success and rapid development of NMR crystallography. However, unusually large errors of predicted hydrogen and carbon chemical shifts are sometimes reported. An understanding of these deviations is crucial for the reliability of NMR crystallography. Here, recently reported large deviations of predicted hydrogen and carbon chemical shifts of a series of solid pyridinium fumarates are thoroughly analyzed. The influence of the geometry optimization protocol and of the computational level of NMR calculations on the accuracy of predicted chemical shifts is investigated. Periodic calculations with GGA, meta-GGA and hybrid functionals are employed. Furthermore, molecular corrections at the coupled-cluster singles-and-doubles (CCSD) level are calculated. The effect of nuclear delocalization on the structure and NMR shielding is also investigated. The geometry optimization with a computationally demanding hybrid functional leads to a substantial improvement in proton chemical-shift predictions.

Four Spacetime Dimensional Simulation of Rheological Waves in Solids and the Merits of Thermodynamics

The recent results attained from a thermodynamically conceived numerical scheme applied on wave propagation in viscoelastic/rheological solids are generalized here, both in the sense that the scheme is extended to four spacetime dimensions and in the aspect of the virtues of a thermodynamical approach. Regarding the scheme, the arrangement of which quantity is represented where in discretized spacetime, including the question of appropriately realizing the boundary conditions, is nontrivial. In parallel, placing the problem in the thermodynamical framework proves to be beneficial in regards to monitoring and controlling numerical artefacts—instability, dissipation error, and dispersion error. This, in addition to the observed preciseness, speed, and resource-friendliness, makes the thermodynamically extended symplectic approach that is presented here advantageous above commercial finite element software solutions.

Thermodynamical Extension of a Symplectic Numerical Scheme with Half Space and Time Shifts Demonstrated on Rheological Waves in Solids

On the example of the Poynting–Thomson–Zener rheological model for solids, which exhibits both dissipation and wave propagation, with nonlinear dispersion relation, we introduce and investigate a finite difference numerical scheme. Our goal is to demonstrate its properties and to ease the computations in later applications for continuum thermodynamical problems. The key element is the positioning of the discretized quantities with shifts by half space and time steps with respect to each other. The arrangement is chosen according to the spacetime properties of the quantities and of the equations governing them. Numerical stability, dissipative error, and dispersive error are analyzed in detail. With the best settings found, the scheme is capable of making precise and fast predictions. Finally, the proposed scheme is compared to a commercial finite element software, COMSOL, which demonstrates essential differences even on the simplest—elastic—level of modeling.

Dynamics of Solid Proteins by Means of Nuclear Magnetic Resonance Relaxometry

¹H Nuclear magnetic resonance (NMR) relaxometry was exploited to investigate the dynamics of solid proteins. The relaxation experiments were performed at 37 °C over a broad frequency range, from approximately 10 kHz to 40 MHz. Two relaxation contributions to the overall ¹H spin-lattice relaxation were revealed; they were associated with ¹H-¹H and ¹H-¹⁴N magnetic dipole-dipole interactions, respectively. The ¹H-¹H relaxation contribution was interpreted in terms of three dynamical processes occurring on timescales of 10^-6 s, 10^-7 s, and 10^-8 s, respectively. The ¹H-¹⁴N relaxation contribution shows quadrupole relaxation enhancement effects. A thorough analysis of the data was performed revealing similarities in the protein dynamics, despite their different structures. Among several parameters characterizing the protein dynamics and structure (e.g., electric field gradient tensor at the position of ¹⁴N nuclei), the orientation of the ¹H-¹⁴N dipole-dipole axis, with respect to the principal axis system of the electric field gradient, was determined, showing that, for lysozyme, it was considerably different than for the other proteins. Moreover, the validity range of a closed form expression describing the ¹H-¹⁴N relaxation contribution was determined by a comparison with a general approach based on the stochastic Liouville equation.

Increased diet viscosity by oat β-glucans decreases the passage rate of liquids in the stomach and affects digesta physicochemical properties in growing pigs

Rheological properties of digesta play a role in digesta passage kinetics through the gastrointestinal tract, in turn affecting nutrient absorption kinetics. Therefore, we studied the effects of diet viscosity on digesta passage and physicochemical properties in pigs. Twenty male growing pigs (35 kg body weight at the start) were assigned to one of five diets with increasing dietary concentrations of β-glucans (BG; from 0 % to 10 %), in exchange for maize starch. After a 17-day adaptation period, pigs were euthanised and the mean retention time (MRT) of digesta solids (TiO2) and liquids (Cr-EDTA) in the stomach, and proximal and distal half of the small intestine was quantified. In the stomach, the MRT of liquids, but not of solids, increased when dietary BG level increased (6 min per % dietary BG, P = 0.008 and R2 = 0.35). Concomitantly, stomach DM content (5 g/kg per % dietary BG, P < 0.001 and R2 = 0.53) and apparent digesta viscosity (56 Pa × s at 1/s shear rate per % dietary BG, P = 0.003 and R2 = 0.41) decreased. In the proximal half of the small intestine, no effects of dietary BG level were observed. In the distal half of the small intestine, water-binding capacity (WBC) of digesta increased (0.11 g/g digesta DM per % dietary BG, P = 0.028 and R2 = 0.24) and starch digestibility decreased (0.3% per % dietary BG, P = 0.034 and R2 = 0.23) when dietary BG level increased. In the colon, apparent digesta viscosity at 45/s shear rate increased (0.1 Pa × s per % dietary BG, P = 0.03 and R2 = 0.24) in the proximal half of the colon, and digesta WBC increased (0.06 g/g digesta DM per % dietary BG, P = 0.024 and R2 = 0.26) in the distal half of the colon when dietary BG level increased. To conclude, increasing dietary BG level caused the MRT of liquids, but not that of solids, to increase in the stomach, resulting in reduced separation of the solid and liquid digesta fractions. This caused dilution of the stomach content and reduction in digesta viscosity when dietary BG levels increased. Effects of dietary BG level on physicochemical properties in the proximal small intestine were absent and may have been due to a low DM content. The WBC of digesta in the distal small intestine and colon increased when dietary BG level increased, as did apparent digesta viscosity in the proximal colon. This likely reflects the concentration of BG in digesta when moving through the gastrointestinal tract.

Quantitative assessment of oral phase efficiency: validation of the Test of Masticating and Swallowing Solids (TOMASS)

BACKGROUND

The Test of Masticating and Swallowing Solids (TOMASS) has been developed to provide clinicians with objective data regarding the efficiency of oral phase function and solid bolus ingestion.

AIMS

To determine if the TOMASS will detect changes in the oral phase of swallowing imposed by topical anaesthesia, thus providing validation of its clinical utility.

METHODS & PROCEDURES

Per the standard protocol, 10 healthy participants ate one-quarter of an Arnotts Salada^TM biscuit. The number of bites per cracker, number of masticatory cycles, number of swallows and total time taken were recorded at baseline, following application of topical oral anaesthetic; this was additionally compared with a post-anaesthetic condition. Median and interquartile range (IQR) were calculated. Wilcoxon signed-rank tests were conducted to evaluate trial effect, and Friedman's tests were used to detect differences in the number of bites, number of swallows, number of chews and time taken to eat the crackers.

OUTCOMES & RESULTS

Results indicated that the number of both bites and swallows did not significantly change across conditions (χ²(2) = 0.105, p = 0.949, χ²(2) = 1.357, p = 0.507); however, the number of chews for the anaesthetic condition was significantly higher when compared with the baseline (p = 0.02) and post-anaesthesia conditions (p = 0.02). Further, the durations of ingestion in the anaesthetic condition were significantly longer than the baseline (p = 0.01) and post-anaesthesia (p = 0.01) conditions. Across all measures, there were no differences between baseline and post-anaesthesia conditions.

CONCLUSIONS & IMPLICATIONS

Although further exploration is required, these early data suggest the TOMASS is a sensitive measure in the evaluation of the oral-phase preparation of solid textures.

Operative fasting guidelines and postoperative feeding in paediatric anaesthesia-current concepts

Preoperative fasting period is the prescribed time prior to any procedure done either under general anaesthesia, regional anaesthesia or sedation, when oral intake of liquids or solids are not allowed. This mandatory fasting is a safety precaution that helps to protect from pulmonary aspiration of gastric contents which may occur any time during anaesthesia. We searched PUBMED for English language articles using keywords including child, paediatric, anaesthesia, fasting, preoperative, gastric emptying. We also hand searched references from relevant review articles and major society guidelines. Association of Paediatric Anaesthesiologists of Great Britain and Ireland (APAGBI), the French Language Society of Paediatric Anaesthesiologists and the European Society of Paediatric Anesthetists recommends clear fluid intake upto one hour prior to elective surgery unless specific contraindications exists. Current guidelines recommend fasting duration of 4 hours for breastmilk, 6 hours for milk and light meals and 8 hours for fatty meals. The European Society for Clinical Nutrition and Metabolism (ESPEN) guidelines recommend that oral intake can be initiated within hours of surgery in most patients. While fluids can be started almost immediately, the introduction of solids should be done more cautiously.

Outcomes of an early childhood obesity prevention program in a low-income community: a pilot, randomized trial

BACKGROUND

Obesity is a major and worldwide health problem in children.

OBJECTIVES

The Early Childhood Obesity Prevention Program is a multi-component, randomized, controlled trial of a pilot community-focused obesity prevention program for mother/newborn dyads.

METHODS

Underserved, mother/newborn dyads were recruited to receive a standard home visitation program (Nurturing Families Network, NFN) or an enhanced program (NFN+) that incorporated behavioural change strategies (e.g., goal-setting, problem-solving) and focused on six obesity-associated behaviours (breastfeeding, juice/sugar-sweetened beverages, solids, infant sleep, TV/screen time and soothability) with linkages to community resources. Weight-for-length (WFL) z-score and maternal diet were secondary outcomes.

RESULTS

Fifty-seven dyads were recruited and 47 fully eligible dyads were enrolled (NFN = 21, NFN+ = 26). Forty-one (87.2%) were assessed at 6 months and 34 (72.3%) at 12 months. Retention at 12 months was higher for NFN+ dyads (84.6% vs. 56.1%, p = 0.04). NFN+ mothers were more likely to continue breastfeeding at 6 and 12 months vs. NFN mothers (p = 0.03 and 0.003, respectively), and at 12 months, NFN+ infants had fewer nocturnal awakenings (p = 0.04). There were no differences in other primary outcome measures or in WFL z-score at 6 or 12 months.

CONCLUSIONS

A multi-component behavioural intervention increased breastfeeding duration and decreased nocturnal awakenings in infants of low-income families.

Solution-Based, Template-Assisted Realization of Large-Scale Graphitic ZnO

With a honeycomb single-atomic-layer structure similar to those of graphene and hexagonal boron nitride (hBN), the graphitic phase of ZnO (gZnO) have been predicted to offer many advantages for engineering, including high-temperature stability in ambient conditions and great potential in heterostructure applications. However, there is little experimental data about this hexagonal phase due to the difficulty of synthesizing large-area gZnO for characterization and applications. In this work, we demonstrate a solution-based approach to realize gZnO nanoflakes with thicknesses down to a monolayer and sizes up to 20 μm. X-ray photoelectron spectroscopy, X-ray absorption near-edge spectroscopy, photoluminescence, atomic force microscopy, and electron microscopy characterizations are conducted on synthesized gZnO samples. Measurements show significant changes to the electronic band structure compared to its bulk phase, including an increase of the band gap to 4.8 eV. The gZnO nanosheets also exhibit excellent stability at temperatures as high as 800 °C in ambient environment. This wide band gap layered material provides us with a platform for harsh environment electronic devices, deep ultraviolet optical applications, and a practical alternative for hBN. Our synthesis method may also be applied to achieve other types of 2D oxides.

Understanding band gaps of solids in generalized Kohn-Sham theory

The fundamental energy gap of a periodic solid distinguishes insulators from metals and characterizes low-energy single-electron excitations. However, the gap in the band structure of the exact multiplicative Kohn-Sham (KS) potential substantially underestimates the fundamental gap, a major limitation of KS density-functional theory. Here, we give a simple proof of a theorem: In generalized KS theory (GKS), the band gap of an extended system equals the fundamental gap for the approximate functional if the GKS potential operator is continuous and the density change is delocalized when an electron or hole is added. Our theorem explains how GKS band gaps from metageneralized gradient approximations (meta-GGAs) and hybrid functionals can be more realistic than those from GGAs or even from the exact KS potential. The theorem also follows from earlier work. The band edges in the GKS one-electron spectrum are also related to measurable energies. A linear chain of hydrogen molecules, solid aluminum arsenide, and solid argon provide numerical illustrations.

Assessment of activated sludge, membrane bioreactors and vertical flow wetlands for upgrading sewage treatment works

This paper demonstrates that utilising a vertical flow (VF) wetland after a conventional activated sludge (CAS) delivers equivalent or better effluent quality to a membrane bioreactor (MBR) based on a side-by-side pilot trial. The CAS was operated under the solids retention times (SRT) of 6, 12, and 20 days, with the effluent from each pilot plant fed onto a soil aquifer treatment column to better understand their water reuse application potential. Results showed an upgraded CAS + VF system could deliver effluents with median values of 34 mgO₂.L^-1, 7 mg.L^-1 and 1.9 mg.L^-1 for organics, solids and ammonia nitrogen, respectively, which were statistically similar to those from the MBR. Water reuse standards were achieved by the upgraded system for most parameters, with the exception of total coliform removal. The upgraded system delivered superior metal removal when compared to the CAS. An economic analysis showed upgrading a CAS with a VF wetland was more favourable than investing in an MBR system for example works of 5000 and 50,000 population equivalents if the VF system was operated at hydraulic loading rates of 0.03 m.d^-1 and 0.08 m.d^-1, respectively. This was delivered for a tenth of the carbon footprint of the MBR treatment.

Gastric emptying of solids in children: reference values for the (13) C-octanoic acid breath test

BACKGROUND

(99m) Technetium scintigraphy ((99m) TS) is the 'gold standard' for measuring gastric emptying (GE), but it is associated with a radiation exposure. For this reason, the (13) C-octanoic acid breath test ((13) C-OBT) was developed for measuring GE of solids. The objective of this study was to determine normal values for gastric half-emptying time (t1/2 GE) of solids in healthy children.

METHODS

Gastric emptying of a standardized solid test meal consisting of a pancake evaluated with (99m) TS and (13) C-OBT was compared in 22 children aged between 1 and 15 years with upper gastrointestinal symptoms. Subsequently, the (13) C-OBT was used to determine normal values for GE of the same solid test meal in 120 healthy children aged between 1 and 17 years.

KEY RESULTS

The results showed a significant correlation (r = 0.748, p = 0.0001) between t1/2 GE measured with both techniques in the group of children with upper gastrointestinal symptoms. In the group of healthy children, mean t1/2 GE was 157.7 ± 54.0 min (range 71-415 min), but t1/2 GE decreased with age between 1 and 10 years and remained stable afterward. There was no influence of gender, weight, height, body mass index, and body surface area on t1/2 GE.

CONCLUSIONS & INFERENCES

Normal values for GE of solids measured with the (13) C-OBT using a standardized methodology were determined in healthy children. We propose to use this method and corresponding reference ranges to study GE of solids in children with gastrointestinal problems.

Encoding Gaussian curvature in glassy and elastomeric liquid crystal solids

We describe shape transitions of thin, solid nematic sheets with smooth, preprogrammed, in-plane director fields patterned across the surface causing spatially inhomogeneous local deformations. A metric description of the local deformations is used to study the intrinsic geometry of the resulting surfaces upon exposure to stimuli such as light and heat. We highlight specific patterns that encode constant Gaussian curvature of prescribed sign and magnitude. We present the first experimental results for such programmed solids, and they qualitatively support theory for both positive and negative Gaussian curvature morphing from flat sheets on stimulation by light or heat. We review logarithmic spiral patterns that generate cone/anti-cone surfaces, and introduce spiral director fields that encode non-localized positive and negative Gaussian curvature on punctured discs, including spherical caps and spherical spindles. Conditions are derived where these cap-like, photomechanically responsive regions can be anchored in inert substrates by designing solutions that ensure compatibility with the geometric constraints imposed by the surrounding media. This integration of such materials is a precondition for their exploitation in new devices. Finally, we consider the radial extension of such director fields to larger sheets using nematic textures defined on annular domains.

Carrier effects on tertiary nitrifying moving bed biofilm reactor: An examination of performance, biofilm and biologically produced solids

Increasingly stricter ammonia and nitrogen release regulations with respect to wastewater effluents are creating a need for tertiary treatment systems. The moving bed biofilm reactor (MBBR) is being considered as an upgrade option for an increasing number of wastewater treatment facilities due to its small footprint and ease of operation. Despite the MBBRs creation as a system to remove nitrogen, recent research on MBBR systems showing that the system's performance is directly related to carrier surface area and is irrespective of carrier shape and type has been performed exclusively on chemical oxygen demand (COD) removal systems. Furthermore, the influence of carrier type on the solids produced by MBBR systems has also been exclusively studied for COD removal systems. This work investigates the effects of three specific carrier types on ammonia removal rates, biofilm morphology, along with solids production and settleability of tertiary nitrifying MBBR systems. The study concludes that carrier type has no significant effect on tertiary nitrifying MBBR system performance under steady, moderate loading conditions. The research does however highlight the propensity of greater surface area to volume carriers to become clogged under high loading conditions and that the high surface area carriers investigated in this study required longer adjustment periods to changes in loading after becoming clogged.

Factors influencing first-time mothers' introduction of complementary foods: a qualitative exploration

BACKGROUND

Optimal infant nutrition comprises exclusive breastfeeding, with complementary foods introduced from six months of age. How parents make decisions regarding this is poorly studied. This study begins to address the dearth of research into the decision-making processes used by first-time mothers relating to the introduction of complementary foods.

METHODS

This qualitative explorative study was conducted using interviews (13) and focus groups (3). A semi-structured interview guide based on the Theory of Planned Behaviour (TPB). The TPB, a well-validated decision-making model, identifies the key determinants of a behaviour through behavioural beliefs, subjective norms, and perceived behavioural control over the behaviour. It is purported that these beliefs predict behavioural intention to perform the behaviour, and performing the behaviour. A purposive, convenience, sample of 21 metropolitan parents recruited through advertising at local playgroups and childcare centres, and electronically through the University community email list self-selected to participate. Data were analysed thematically within the theoretical constructs: behavioural beliefs, subjective norms and perceived behavioural control. Data relating to sources of information about the introduction of complementary foods were also collected.

RESULTS

Overall, first-time mothers found that waiting until six months was challenging despite knowledge of the WHO recommendations and an initial desire to comply with this guideline. Beliefs that complementary foods would assist the infants' weight gain, sleeping patterns and enjoyment at meal times were identified. Barriers preventing parents complying with the recommendations included subjective and group norms, peer influences, infant cues indicating early readiness and food labelling inconsistencies. The most valued information source was from peers who had recently introduced complementary foods.

CONCLUSIONS

First-time mothers in this study did not demonstrate a good understanding of the rationale behind the WHO recommendations, nor did they understand fully the signs of readiness of infants to commence solid foods. Factors that assisted waiting until six months were a trusting relationship with a health professional whose practice and advice was consistent with the recommendations and/or when their infant was developmentally ready for complementary foods at six months and accepted them with ease and enthusiasm. Barriers preventing parents complying with the recommendations included subjective and group norms, peer influences, infant cues indicating early readiness and food labelling inconsistencies.

Timing and Determinants of the Introduction of Complementary Foods in Kuwait: Results of a Prospective Cohort Study

BACKGROUND

The early introduction of complementary foods is common in Middle Eastern countries but little is known about the determinants of this practice in this region.

OBJECTIVES

This prospective cohort study conducted from October 2007 to October 2008 investigated the determinants of the very early (before 17 weeks) introduction of complementary foods in Kuwait and compared rates of this practice against rates reported in the mid-1990s.

METHODS

A total of 373 women were recruited from maternity hospitals in Kuwait City and followed to 26 weeks postpartum. Data on complementary feeding practices were available from 303 women. Multivariate logistic regression was used to estimate the association of very early introduction of complementary foods with infant sex and maternal characteristics including age, years of education, employment intentions at 6 months postpartum, parity, prepregnancy body mass index, and prepregnancy smoking status.

RESULTS

All infants had received complementary foods by 26 weeks of age, with 30.4% receiving complementary foods before 17 weeks of age. Women born in other Arabic countries were less likely to introduce complementary foods before 17 weeks (adjusted odds ratio [adj OR] = 0.40; 95% confidence interval [CI], 0.22-0.73) than women born in Kuwait. Women who were exclusively formula feeding at 6 weeks postpartum were less likely to introduce complementary foods before 17 weeks (adj OR = 0.40; 95% CI, 0.23-0.71) than women who were still breastfeeding.

CONCLUSION

Compared to the mid-1990s, fewer infants in Kuwait were receiving complementary foods before 17 weeks. Nevertheless, all infants had received complementary foods by 6 months of age.

Timing and Determinants of the Introduction of Complementary Foods in Kuwait: Results of a Prospective Cohort Study

BACKGROUND

The early introduction of complementary foods is common in Middle Eastern countries but little is known about the determinants of this practice in this region.

OBJECTIVES

This prospective cohort study conducted from October 2007 to October 2008 investigated the determinants of the very early (before 17 weeks) introduction of complementary foods in Kuwait and compared rates of this practice against rates reported in the mid-1990s.

METHODS

A total of 373 women were recruited from maternity hospitals in Kuwait City and followed to 26 weeks postpartum. Data on complementary feeding practices were available from 303 women. Multivariate logistic regression was used to estimate the association of very early introduction of complementary foods with infant sex and maternal characteristics including age, years of education, employment intentions at 6 months postpartum, parity, prepregnancy body mass index, and prepregnancy smoking status.

RESULTS

All infants had received complementary foods by 26 weeks of age, with 30.4% receiving complementary foods before 17 weeks of age. Women born in other Arabic countries were less likely to introduce complementary foods before 17 weeks (adjusted odds ratio [adj OR] = 0.40; 95% confidence interval [CI], 0.22-0.73) than women born in Kuwait. Women who were exclusively formula feeding at 6 weeks postpartum were less likely to introduce complementary foods before 17 weeks (adj OR = 0.40; 95% CI, 0.23-0.71) than women who were still breastfeeding.

CONCLUSION

Compared to the mid-1990s, fewer infants in Kuwait were receiving complementary foods before 17 weeks. Nevertheless, all infants had received complementary foods by 6 months of age.

Bottle and sippy cup use is associated with diet and energy intake in toddlers

The second year of life incorporates a continued shift from a liquid- to solid-based diet. Little is known about the prevalence and dietary impact of bottle and sippy cup use. This paper describes associations between percent of energy consumed via drinking containers (bottles and sippy cups combined) and dietary outcomes, between 1 and 2 years of age. This observational study recruited n = 299 low-income, nutrition programme clients from the Bronx, NY, whose 12 month olds consumed ≥ 2 non-water bottles per day. The main exposure variable was percent of energy intake via drinking containers (PEDC), dichotomized at the median into low-percent-energy-from-drinking-containers (LOW-C) and high-percent-energy-from-drinking-containers (HIGH-C) groups, assessed quarterly, for 1 year. We report 24-hour dietary recall nutrient and food serving data by LOW-C vs. HIGH-C. We employed linear mixed models to study associations between PEDC and nutrient intake. PEDC decreased from 52% to 33% between 1 and 2 years of age in both groups. The LOW-C group had higher intake of energy, dietary fibre, iron and sodium, grains, protein-rich foods and sweets. Conversely, LOW-C group had lower intake of Vitamin D and calcium vs. the HIGH-C group. PEDC was inversely associated with total energy intake in a model controlling for baseline age, baseline-weight-for-length and gender (β = -5.8, P = 0.029, 95% confidence interval (-10.96, -0.6). Lower bottle and sippy cup use had significant, albeit mixed association with diet quality in the second year of life, and was associated with higher energy intake. Evidence-based guidelines are needed to determine the appropriate use of those feeding methods.

Determinants of inappropriate timing of introducing solid, semi-solid or soft food to infants in Pakistan: secondary data analysis of Demographic and Health Survey 2006-2007

Inappropriate timing of introducing complementary food deprives the infant of optimum nutrition, leading to undernutrition, and increased mortality and morbidity. The aim of this analysis was to identify determinants of inappropriate timing of introduction of solid, semi-solid and soft foods in Pakistan. Data on 941 infants 3.00 to 8.99 months were obtained from the Pakistan Demographic and Health Survey 2006-2007. The prevalence of introduction of foods among infants aged 3.00-5.99 months and 6.00-8.99 months was examined against a set of individual, household and community level variables using univariate analysis. Adjusted odds ratio (AOR) for early introduction in age 3.00-5.99 months and non-introduction in 6.00-8.99 months of age were calculated using backward stepwise logistic regression models. The prevalence of early introduction of complementary foods among 3.00- to 5.99-month-old and timely introduction among 6.00- to 8.99-month-old infants were 10.6% and 39.2%, respectively. Multivariate analyses revealed that mothers who had four or more antenatal clinic visits (AOR=2.68) and who lived in the provinces of Sindh (AOR=2.89) and Baluchistan (AOR=6.75) were more likely to introduce complementary foods early. Mothers from middle-level households (AOR=7.82), poorer households (AOR=4.84) and poorest households (AOR=5.72) were significantly more likely to delay introduction of complementary foods. In conclusion more than half (60.8%) of Pakistani infants do not receive complementary foods at recommended time. Public health interventions to improve the timing of introduction of complementary food are needed at national level with special focus on high risk groups.