Optical coupling of gold nanoparticles on vertical graphenes to maximize SERS response.

Gold particle interaction with few-layer graphenes is of interest for the development of numerous optical nanodevices. The results of numerical studies of the coupling of gold nanoparticles with few-layer vertical graphene sheets are presented. The field strengths are computed and the optimum nanoparticle configurations for the formation of surface enhanced Raman spectroscopy (SERS) hotspots are obtained. The nanoparticles are modeled as 8 nm diameter spheres atop 1.5 nm (five layers) graphene sheet. The vertical orientation is of particular interest as it is possible to use both sides of the graphene structure and potentially double the number of particles in the system. Our results show that with the addition of an opposing particle a much stronger signal can be obtained, as well as the particle the number of atomic carbon layers can control separation. These results provide further insights and contribute to the development of next-generation plasmonic devices based on nanostructures with hybrid dimensionality.

Ultrasonicated-ozone modification of exfoliated graphite for stable aqueous graphitic nanoplatelet dispersions.

A novel ultrasonicated-ozonolysis (USO) processing method has been applied to commercially available exfoliated graphite (EG) with the aim of producing stable aqueous graphitic nanoplatelet (GNP) dispersions that are suitable for ink-jet printing and electrophoretic deposition. The processing has been compared to other low energy and environmentally friendly electrochemical exfoliation (EE) techniques. The results show USO can be used to prepare highly stable aqueous dispersions from both low and high surface area EG. The level of oxygen functionalization can be easily controlled with processing time as can the dispersion concentration. The degree of disorder in the GNP structure is similar to existing EE methods but offers higher yields without the need to remove any chemicals post-processing. Ink-jet printing onto heated quartz substrates produced films which reached electrical conductivities of 1400 s m(-1) after annealing. The films printed from USO-processed EGs had higher conductivity and significantly reduced thickness as compared to films printed from aqueous dispersions of reduced graphene oxide.

Plasmonic Ag nanoparticles via environment-benign atmospheric microplasma electrochemistry.

Atmospheric-pressure microplasma-assisted electrochemistry was used to synthesize Ag nanoparticles (NPs) for plasmonic applications. It is shown that the size and dispersion of the nanoparticles can be controlled by variation of the microplasma-assisted electrochemical process parameters such as electrolyte concentration and temperature. Moreover, Ag NP synthesis is also achieved in the absence of a stabilizer, with additional control over the dispersion and NP formation possible. As the microplasma directly reduces Ag ions in solution, the incorporation of toxic reducing agents into the electrolytic solution is unnecessary, making this an environmentally friendly fabrication technique with strong potential for the design and growth of plasmonic nanostructures for a variety of applications. These experiments therefore link microplasma-assisted electrochemical synthesis parameters with plasmonic characteristics.

"It's always hard being a mom, but the pandemic has made everything harder": A qualitative exploration of the experiences of perinatal women during the COVID-19 pandemic.

BACKGROUND: Understanding the psychosocial impacts of the COVID-19 pandemic in vulnerable groups, such as pregnant and parenting women, is a critical research and clinical imperative. Although many survey-based perinatal health studies have contributed important information about mental health, few have given full voice about the experiences of pregnant and postpartum women during the prolonged worldwide pandemic using a qualitative approach. OBJECTIVE: The purpose of this study is to explore the lived experience of pregnant and postpartum women in the United States during the ongoing COVID-19 pandemic. DESIGN: Qualitative phenomenological study. SETTING: This study was conducted in the community, by recruiting women throughout the U.S. PARTICIPANTS: Fifty-four pregnant and postpartum women participated in qualitative interviews. METHODS: Data from one-on-one semi-structured interviews were analyzed using a team-based phenomenological qualitative approach. RESULTS: Two key themes were apparent: the pandemic has shined a light on the many typical struggles of motherhood; and, there is a lack of consistent, community-based or healthcare system resources available to address the complex needs of pregnant and postpartum women, both in general and during the pandemic. CONCLUSIONS: Going forward, as the world continues to deal with the current pandemic and possible future global health crises, health care systems and providers are encouraged to consider the suggestions provided by these participants: talk early and often to women about mental health; help pregnant and postpartum women create and institute a personal plan for early support of their mental health needs and create an easily accessible mental health network; conceptualize practice methods that enhance coping and resilience; practice in community-based and interdisciplinary teams (e.g., midwives, doulas, perinatal social workers/ psychotherapists) to ensure continuity of care and to foster relationships between providers and pregnant/ postpartum women; and consider learning from other countries' successful perinatal healthcare practices. REGISTRATION: Number (& date of first recruitment): not applicable. TWEETABLE ABSTRACT: Pregnant and postpartum women insist that mental health care must be overhauled, stating the pandemic has highlighted inherent cracks in the system.

Minimizing the Gibbs-Thomson effect in the low-temperature plasma synthesis of thin Si nanowires.

An advanced combination of numerical models, including plasma sheath, ion- and radical-induced species creation and plasma heating effects on the surface and within a Au catalyst nanoparticle, is used to describe the catalyzed growth of Si nanowires in the sheath of a low-temperature and low-pressure plasma. These models have been used to explain the higher nanowire growth rates, low-energy barriers, much thinner Si nanowire nucleation and the less effective Gibbs-Thomson effect in reactive plasma processes, compared with those of neutral gas thermal processes. The effects of variation in the plasma sheath parameters and substrate potential on Si nanowire nucleation and growth have also been investigated. It is shown that increasing the plasma-related effects leads to decreases in the nucleation energy barrier and the critical nanoparticle radius, with the Gibbs-Thomson effect diminished, even at low temperatures. The results obtained are consistent with available experimental results and open a path toward the energy- and matter-efficient nucleation and growth of a broad range of one-dimensional quantum structures.

Real-world clinical profile, treatment patterns and patient-reported outcomes in a subset of HR+/HER2- advanced breast cancer patients with poor prognostic factors: data from an international study.

BACKGROUND: Patients with hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) advanced breast cancer (ABC) and disease-related poor prognostic factors are not well characterized. We aimed to describe patient demographics, disease characteristics, treatment patterns and patient-reported outcomes in a subset of HR+/HER2- ABC patients with these factors [at the time when cyclin-dependent kinase (CDK) 4 and 6 inhibitors were being introduced] and understand how these factors informed treatment decisions at the time of the survey. METHODS: Real-world data were derived from a large, multinational, point-in-time survey of oncologists and their consulting patients with HR+/HER2- ABC in the EU5 and USA over March-June 2017, at the start of the changing treatment landscape. Analysis focused on four poor prognostic factors: visceral metastases, liver metastases (subset of visceral metastases), progesterone receptor-negative status and high tumor grade. RESULTS: In total, 2259 patients with HR+/HER2- ABC had records eligible for this analysis. At least one poor prognostic factor was present in 63% of patients (most common visceral metastases; least common progesterone receptor-negative status), with varying degrees of overlap between factors. For physician-reported outcomes, pain increased, whereas performance status and activities of daily living declined with presence of poor prognostic factors, especially liver metastases. No clear trends were observed for patient-reported outcomes. Treatment with combined endocrine therapy plus CDK4 and 6 inhibitors was infrequent, as these agents were entering the market. CONCLUSIONS: More than 60% of the HR+/HER2- ABC Adelphi Real World Disease Specific Programme™ sample had ≥1 disease-related poor prognostic factor, and patients appeared to be heterogeneous regarding occurrence and distribution of these factors. These patients typically have increased pain and reduced performance status, highlighting the importance of implementing effective therapy with CDK4 and 6 inhibitors. Future studies could inform how the treatment landscape has evolved over time with respect to patients with poor prognostic factors.

Discordant responses on starting highly active antiretroviral therapy: suboptimal CD4 increases despite early viral suppression in the UK Collaborative HIV Cohort (UK CHIC) Study.

OBJECTIVES: Patients starting highly active antiretroviral therapy (HAART) may have a suboptimal CD4 increase despite rapid virological suppression. The frequency and the significance for patient care of this discordant response are uncertain. This study was designed to determine the incidence of a discordant response at two time-points, soon after 6 months and at 12 months, and to determine the relationship with clinical outcomes. METHODS: Data obtained in the UK Collaborative HIV Cohort Study were analysed. A total of 2584 treatment-naïve patients starting HAART with HIV viral load (VL) > 1000 HIV-1 RNA copies/mL at baseline and < 50 copies/mL within 6 months were included in the analysis. Patients were classified at either 6-10 (midpoint 8) months or 10-14 (midpoint 12) months as having a discordant (CD4 count increase < 100 cells/microL from baseline) or concordant response (CD4 count increase >or= 100 cells/microL). RESULTS: Discordant responses occurred in 32.1% of patients at 8 months and in 24.2% at 12 months; 35% of those discordant at 8 months were concordant at 12 months. A discordant response was associated with older age, lower baseline VL, and (at 12 months) higher baseline CD4 cell count. In a multivariate analysis it was associated with an increased risk of death, more strongly at 12 months [incidence rate ratio (IRR) 3.35, 95% confidence interval (CI) 1.73-6.47, P < 0.001] than at 8 months (IRR 2.08, 95% CI 1.19-3.64, P = 0.010), but not with new AIDS events. CONCLUSIONS: Discordant responders have a worse outcome, but assessment at 12 months may be preferred, given the number of 'slow' responders. Management strategies to improve outcomes for discordant responders need to be investigated.

Low- and high-temperature controls in carbon nanofiber growth in reactive plasmas.

A numerical growth model is used to describe the catalyzed growth of carbon nanofibers in the sheath of a low-temperature plasma. Using the model, the effects of variation in the plasma sheath parameters and substrate potential on the carbon nanofiber growth characteristics, such as the growth rate, the effective carbon flux to the catalyst surface, and surface coverages, have been investigated. It is shown that variations in the parameters, which change the sheath width, mainly affect the growth parameters at the low catalyst temperatures, whereas the other parameters such as the gas pressure, ion temperature, and percentages of the hydrocarbon and etching gases, strongly affect the carbon nanofiber growth at higher temperatures. The conditions under which the carbon nanofiber growth can still proceed under low nanodevice-friendly process temperatures have been formulated and summarized. These results are consistent with the available experimental results and can also be used for catalyzed growth of other high-aspect-ratio nanostructures in low-temperature plasmas.

Feed particle selection and nutrient intake altered by pecking stone consumption and beak length in free-range laying hens.

The present study investigated the effects of pecking stones on feeding behaviour of hens from 16 to 46 weeks of age. Eighteen flocks of Hy-Line Brown hens were housed in 2 commercial free-range housing systems. Farm A housed 10 flocks of beak trimmed (infrared beak treatment) hens in fixed sheds. Farm B housed 8 flocks of hens with intact beaks in mobile sheds. On each farm, flocks were equally assigned to control groups (no access to pecking stones) and treatment groups (access to pecking stones). Data were evaluated every 10 weeks. At each time point, 10 hens per flock were housed in individual pens, and each hen was provided with 250 g of mash diet and ad libitum water for 24 h. After 24 h, feed samples were collected and used to determine 24-h feed intake. Nutrient and particle selection was measured by subtracting nutrients and particles present in the leftover feed from the vaules obtained in the offered feed and expressed the change (Δ). In addition, pecking stone consumption was recorded for each flock. Data were analysed separately for each farm using fixed effects of pecking stone availability and hen age. Spearman's rho correlation coefficients and linear regression models were constructed to evaluate the relationship of beak length and pecking stone usage, discrete mean particle size (dMEAN) consumption (Δ dMEAN), and Δ nutrient intake. Hens with access to pecking stones consumed significantly lower quantities of large feed particles (>2.8 mm) on farm A (P = 0.029) and selected significantly more fine particles, on farm B (P = 0.013). Overall, positive relationships (P = 0.001) between beak length and pecking stone consumption, Δ dMEAN, and Δ phosphorus consumption were observed. In conclusion, pecking stone consumption resulted in reduced selection and consumption of feed particles in hens housed on both farms. Further research is warranted to investigate the effect of pecking stones on sensory innervation of the beak.

Enzymes and/or combination of organic acid and essential oils supplementation in pasture-fed free-range laying hens increased the digestibility of nutrients and non-starch polysaccharides.

Pasture intake can be a major challenge for free-ranging hens. This study was conducted to examine pasture digestion and to manage its negative effects. A total of 300 ISA Brown laying hens were used to investigate the effect of time on range (T) in short-term (6 wk) and long-term (12 wk) of 2 range types (R) (gravel vs. pasture) and dietary supplements (F) (T1 = xylanase; T2 = xylanase/beta-glucanase/pectinase/protease; T3 = xylanase/benzoic acid/essential oils) on crude protein, crude fiber, acid detergent fiber, neutral detergent fiber, non-starch polysaccharides (NSP), calcium and phosphorus digestibility, pH of the crop, and ileum digesta viscosity and morphology. Hens exposed to the range for 12 wk had lower (P < 0.05) digestibility of crude protein, insoluble rhamnose, ribose, and lower ileal pH compared to hens that ranged for 6 wk. Hens ranging on pasture had lower digestibility (P < 0.05) of crude protein, acid detergent fiber, neutral detergent fiber, insoluble arabinose, and insoluble xylose, but higher digestibility (P < 0.05) of insoluble mannose and glucose compared to hens that ranged on gravel. Hens fed T2 and T3 had higher digestibility (P < 0.05) of CP, acid detergent fiber, and neutral detergent fiber compared to hens fed T1. Hens fed T2 had higher digestibility (P < 0.05) of free oligosaccharide arabinose and xylose than those fed T1 or T3 diets. A significant interaction between T × R was detected for crude fiber digestibility and villus height. Digestibility of crude fiber was reduced and villus height was increased in hens ranged on pasture for 12 wk compared to 6 wk. An interaction between R × F was observed on phosphorus and soluble NSP digestibility (P < 0.05). Hens fed T2 and T3 diets had lower digestibility of phosphorus and NSP on gravel than on pasture. In conclusion, pasture consumption impaired the digestibility of nutrients. Supplementing free-range diets with a multi-enzyme or xylanase/benzoic acid/essential oil product reduced these negative effects and increased the ileal nutrient digestibility.

Absorption of L-methionine from the human small intestine.

Absorption of L-methionine was measured in all parts of the human small intestine using transintestinal intubation and perfusion. In four normal subjects, adsorption was higher in the proximal than in the distal intestine. In two patients with nontropical sprue in relapse, there was a proximal zone of low absorption with higher absorption distally. In all parts of the small intestine, absorption showed rate-limiting kinetics as methionine concentration was increased. In normal subjects, the proximal K(m) (Michaelis constant) was more than 3 times higher than the distal, which suggests a difference in transport mechanisms between the two segments.

The electrophysiologic effects of quinidine in the transplanted human heart.

Using His bundle recording techniques, we examined direct and autonomically mediated conduction system effects of quinidine in five cardiac transplant recipients who have anatomically denervated hearts. We made control conduction interval and refractory period measurements, and then infused 10 mg/kg quinidine gluconate over a 20-min period. At 30 min, we determined the electrophysiologic changes induced by quinidine. Quinidine significantly increased the atrial-His (AH) interval (from 97+/-9 [SEM] to 108+/-7 ms, P less than 0.001), the His-ventricular (HV) inteval (from 43.9 +/- 1 to 52.8 +/- 3 ms, P less than 0.01), the donor heart sinus cycle length (from 599 +/- 38 to 630 +/- 56 ms, P less than 0.08), and the atrial effective refractory period (from 214 +/- 14 to 241 +/- 11 ms, P less than 0.01). Quinidine significantly decreased the innervated, remnant atrial sinus cycle length (from 847 +/- 104 to 660 +/- 96 ms, P less than 0.01) and the blood pressure. The mean plasma concentration of quinidine at the time that electrophysiologic measurements were repeated was 4.37 +/- 0.449 micrograms/ml. We conclude that quinidine's predominant sinus nodal and atrioventricular nodal effects in man are autonomically mediated and opposite to its direct actions upon these structures. On the other hand, quinidine's prevailing effect on atrial refractoriness and His-Purkinje conduction in man is direct.

Apparent and standardized ileal nutrient digestibility of broiler diets containing varying levels of raw full-fat soybean and microbial protease.

BACKGROUND: Although soybean meal (SBM) is excellent source of protein in diets for poultry, it is sometimes inaccessible, costly and fluctuates in supply. The SBM can partially be replaced by full-fat SBM, but the meals prepared from raw full-fat soybean contain antinutritional factors. To avoid the risk of antinutritional factors, heat treatment is always advisable, but either excessive or under heating the soybean could negatively affect the quality. However, the potential for further improvement of SBM by supplementing with microbial enzymes has been suggested by many researchers. The objective of this study was to evaluate the performance and ileal nutrient digestibility of birds fed on diets containing raw soybeans and supplemented with microbial protease. METHODS: A 3 × 2 factorial, involving 3 levels of raw full-fat soybean (RFFS; 0, 45 or 75 g/kg of diet) and 2 levels of protease (0 or 15,000 PROT/kg) was used. The birds were raised in a climate-controlled room. A nitrogen-free diet was also offered to a reference group from day 19 to 24 to determine protein and amino acid flow at the terminal ileum and calculate the standardized ileal digestibility of nutrients. On days 10, 24 and 35, body weight and feed leftover were recorded to calculate the body weight gain (BWG), feed intake (FI) and feed conversion ratio (FCR). On day 24, samples of ileal digesta were collected at least from two birds per replicate. RESULTS: When RFFS was increased from 0 to 75 g/kg of diet, the content of trypsin inhibitors was increased from 1747 to 10,193 trypsin inhibitors unit (TIU)/g of diets, and feed consumption of birds was also reduced (P < 0.05). Increasing RFFS level reduced the BWG from hatch 0 to 10 d (P < 0.01) and hatch to 24 d (P < 0.05). The BWG of birds from hatch to 35 was not significantly (P = 0.07) affected. Feed intake was also reduced (P < 0.05) during 0 to 35 d. However, protease supplementation improved (P < 0.05) the BWG and FCR during 0 to 24 d. Rising levels of RFFS increased the weight of pancreas (P < 0.001) and small intestine (P < 0.001) at day 24. Except for methionine, apparent and the corresponding standardized ileal digestibility of CP and AA were reduced (P < 0.01) by increasing levels of RFFS in diets. CONCLUSION: This study showed that some commercial SBM could be replaced by RFFS in broiler diets, without markedly compromising productivity. The AID and SID of CP and lysine were slightly improved by dietary supplementation of microbial protease.

The Middle East and Eastern Europe rabies Expert Bureau (MEEREB) third meeting: Lyon-France (7-8 April, 2015).

MEEREB is an inter-regional network of countries from North Africa, Europe, the Middle East and Central Asia that work together with the aim of improving rabies control and prevention at local, regional and global level. MEEREB members met for the third time in 2015 in France (Lyon) to review the current rabies situation within the network and to discuss the way forward the prospect of a One Health approach against rabies. Dogs were the main vector of transmission in all MEEREB countries except for Croatia and Serbia where foxes represented the primary source. The number of rabies animal cases reported in 2014 varied substantially between countries with Ukraine reporting the highest number of animal cases. Human cases still occur in North Africa and all Middle East and Eurasian countries while no cases of human rabies were reported in Croatia, Serbia and Romania, although cases of rabies were identified in both dogs and foxes in 2014. Participants concluded that MEEREB can act as a think-tank where countries can share data, information, experiences and best practices to jointly address challenges in rabies control and prevention. They called for elimination of dog-transmitted rabies through vaccine and rabies immunoglobulin stockpiles and implementation of a One Health approach to achieve rabies's eradication.

Small intestinal glucose transport. Proximal-distal kinetic gradients.

Proximal and distal small intestinal segments of the rat were perfused in situ at two different rates with isotonic solutions containing glucose in concentrations ranging from 25 to 600 mg/100 ml. Absorption was measured as glucose disappearance rate from the lumen. Glucose absorption had not previously been studied at intraluminal concentrations above and below blood glucose. Absorption was more rapid from the proximal segment. In both segments absorption was independent of perfusion rate and of whether glucose was analyzed by counting (14)C or by the Somogyi method. The latter finding suggests that of the unidirectional fluxes, flux out of the bowel is much greater than flux into the bowel. In contrast to the findings in previous studies neither segment showed rate-limiting kinetics, and the Michaelis-Menten analysis was not applicable. The form of the curve depicting absorption rate in relation to concentration differed between the two segments. At the higher concentrations absorption rate continued to increase much more rapidly in the proximal than in the distal segment. The observations could not be explained by known mechanisms of glucose transport and illustrate the difficulties of achieving biochemically and physiologically meaningful in vivo studies of intestinal absorption.

Genetic determinants on rat chromosome 6 modulate variation in the hypercapnic ventilatory response using consomic strains.

To understand the genetic basis of pathways involved in the control of breathing, a large scale, high-throughput study using chromosomal substitution strains of rats is underway. Eight new consomic rat stains (SS-2(BN), SS-4(BN), SS-6(BN), SS-7(BN), SS-8(BN), SS-11(BN), SS-12(BN), SS-14(BN), SS-Y(BN)), containing one homozygous BN/NHsdMcwi (BN) chromosome on a background of SS/JrHsdMcwi (SS), were created by PhysGen (http://pga.mcw.edu) Program for Genomic Applications. Male and female rats were studied using standard plethysmography under control conditions and during acute hypoxia (inspired oxygen fraction = 0.12) and hypercapnia (inspired CO(2) fraction = 0.07). The rats were also studied during treadmill exercise. Both male and female BN rats had a significantly lower ventilatory response during 7% CO(2) compared with SS rats of the same gender. SS-6(BN) female rats had a significantly reduced ventilatory response, similar to BN rats due primarily to a reduced tidal volume. Male SS-6(BN) rats had a significantly reduced tidal volume response to hypercapnia but a slightly increased frequency response during hypercapnia. Gene(s) on the Y chromosome may play a role in this increased frequency response in the male rats because the SS-Y(BN) hypercapnic ventilatory response involves a significantly increased frequency response. Several chromosomal substitutions slightly altered the ventilatory responses to hypoxia and exercise. However, genes on chromosomes 6 and Y of those studied are of primary importance in aspects of ventilatory control currently studied.

Diet, nutrition intake, and metabolism in populations at high and low risk for colon cancer. Population: demographic and anthropometric characteristics.

A study was designed to compare nutritional and metabolic parameters on subjects with a spectrum of vegetarian and nonvegetarian dietary patterns. The method of selection of the study population, the description of its characteristics, and the data collection protocol are described. Anthropometric measurements of vegetarians and nonvegetarians are reported and compared with previously reported measurements on similar populations.

Diet, nutrition intake, and metabolism in populations at high and low risk for colon cancer. Laboratory analysis of 3-day composite of food samples.

In a study designed to characterize dietary patterns of vegetarian and nonvegetarian populations, chemical analysis of 3-day composite food samples showed lower fat content of food of vegetarians than that of nonvegetarians; pure vegetarians had the lowest. Unsaturated fatty acids were highest in the food of the pure vegetarian group. No significant difference was seen in percentage protein of the food consumed by male vegetarians and nonvegetarians while the food of female vegetarians was of lower protein content than that of the nonvegetarians. The relationship of these findings to the lower incidence of colon cancer in vegetarian populations remains to be determined.