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BackgroundPulmonary Tuberculosis (PTB) is a major health problem in prisons. Multiple studies of TB in regional Ethiopian prisons have assessed prevalence and risk factors but have not examined recently implemented screening programs for TB in prisons. This study compares bacteriologically-confirmed PTB (BC-PTB) prevalence in prison entrants versus residents and identifies risk factors for PTB in Kality prison, a large federal Ethiopian prison located in Addis Ababa, through a study of an enhanced TB screening program.MethodsParticipating prisoners (n = 13,803) consisted of 8,228 entrants screened continuously and 5,575 residents screened in two cross-sectional waves for PTB symptoms, demographics, TB risk factors, and medical history. Participants reporting at least one symptom of PTB were asked to produce sputum which was examined by microscopy for acid-fast bacilli, Xpert MTB/RIF assay and MGIT liquid culture. Prevalence of BC-PTB, defined as evidence of Mycobacterium tuberculosis (MTB) in sputum by the above methods, was compared in entrants and residents for the study. Descriptive analysis of prevalence was followed by bivariate and multivariate analyses of risk factors.ResultsPrisoners were mainly male (86%), young (median age 26 years) and literate (89%). Prevalence of TB symptoms by screening was 17% (2,334/13,803) with rates in residents >5-fold higher than entrants. Prevalence of BC-PTB detected by screening in participating prisoners was 0.16% (22/13,803). Prevalence in residents increased in the second resident screening compared to the first (R1 = 0.10% and R2 = 0.39%, p = 0.027), but remained higher than in entrants (4.3-fold higher during R1 and 3.1-fold higher during R2). Drug resistance (DR) was found in 38% (5/13) of culture-isolated MTB. Risk factors including being ever diagnosed with TB, history of TB contact and low Body Mass Index (BMI) (ConclusionsBC-PTB prevalence was strikingly lower than previously reported from other Ethiopian prisons. PTB appears to be transmitted within this prison based on its higher prevalence in residents than in entrants. Whether a sustained program of PTB screening of entrants and/or residents reduces prevalence of PTB in prisons is not clear from this study, but our findings suggest that resources should be prioritized to resident, rather than entrant, screening due to higher BC-PTB prevalence. Detection of multi- and mono-DR TB in both entrant and resident prisoners warrants regular screening for active TB and adoption of methods to detect drug resistance.

As a form of environmental degradation, soil degradation directly or indirectly affects many lives through decreased agricultural yields, increased flooding and habitat loss. Soil loss has been increasing in most parts of the world and is most pronounced in tropical developing countries where there is poor or zero soil and water conservation (SWC) planning and management activities. Identifying areas prone to soil erosion has also been inadequate, having not been informed by dedicated scientific studies. This is true of the poorly understood watershed of Welmel in the Oromia region of Ethiopia, where most livelihoods heavily rely upon agriculture. To plan effective SWC management techniques, a solid knowledge of spatial variations across different climate, land use and soil erosion is essential. This study has aimed at identifying potential areas needing SWC practices through conducting a spatial modeling of soil erosion within the Welmel watershed’s Genale Dawa basin using a geographic information system (GIS), remote sensing (RS), multiple factors as land uses and climate. The Welmel catchment is located in southeastern Ethiopia and extends between 5°0′0″ N–7°45′00″ N and 39°0′0″ E–41°15′0″ E. The revised universal soil loss equation (RUSLE), which was previously adapted to Ethiopian conditions, was used to estimate potential soil loss. It used information on interpolated rainfall erosivity (R), soil erodibility (K), vegetation cover (C) and topography (LS) from a digital elevation model (DEM) and that of conservation practices (P) from satellite images. The study demonstrates that the RUSLE using GIS and RS considering different climates and land management practices provides a great advantage in that it allows one to spatially analyze multilayer data in order to identify soil erosion-prone areas and thereby develop the most appropriate watershed management strategy. The mean soil loss was determined to be 31 tons ha−1 year−1 and it varied between 0 and 169 tons ha−1 year−1. About 79% of the watershed lies within the tolerable level of 11 tons ha−1 year−1. However, the remaining 21% has a high soil truncation trait, mainly due to its steeper slope and use as cultivated land. Our study identifies cultivated and deforested areas of the watershed as the potential SWC practice demanding areas. Thus, the application of RUSEL using GIS across different land management practices and climate zones is a potential tool for identifying SWC demanding sites. This remains helpful in efforts towards sustainable land management practices for the sustainable livelihood of the local human population.

Friction is the resisting force between two bodies having relative motion. These bodies can be solid surfaces, fluid films or elements sliding against each other. There are many devices used to overcome sliding friction which include wheels and bearings. Ball bearings are used in many high speed and high precision machine tools because of their high productivity. A Crank-Rocker four bar mechanism consists of 4 linkages and 4 nodes. These nodes perform complex motions especially the coupler-rocker joint. In order to reduce the friction between these relatively moving links, ball bearings can be introduced. The coupler-rocker bearing oscillates about some axis as well as the raceways have some relative motion. Heat generation rate is not known for bearings performing this type of complex motion. This paper describes the mathematical modelling and thermal analysis of coupler-rocker bearing. Heat generation in the bearing can be estimated using this model. This can be countered by having proper lubrication and speed of bearing.

Supersonic separator is a new technology with applications in hydrocarbon dew pointing and gas dehydration which can be used to condensate and separate water and heavy hydrocarbons from natural gas. Many researchers have studied the design, performance and efficiency, economic viability, and industrial applications of these separators. The purpose of this paper is to succinctly review recent progress in the design and application of supersonic separators and their limitations. This review has found that while several aspects of this study are well studied, considerable gaps within the published literature still exists in the areas such as turndown flexibility which is a critical requirement to cater for variation of mass flow and since almost all the available designs have a fixed geometry and therefore cannot be considered suitable for variable mass flow rate, which is a common situation in actual site. Hence, the focus needs to be more on designing a flexible geometry that can maintain a high separation efficiency regardless of inlet conditions and mass flow variations. This review is focusing only on the design and application of the supersonic separators without going through the experimental facilities, industrial platform, pilot plants as well as theoretical, analytical, and numerical modelling.

Background: Malaria is a critical public health concern in Ethiopia, with significant socioeconomic consequences. Malaria data trend analysis is essential for understanding transmission patterns and adopting evidence-based malaria control measures. The purpose of this study was to determine the 5 year distribution of malaria in North Shewa zone, Amhara region, Ethiopia, in 2023., Methods: A descriptive cross-sectional study design was employed to analyse the 5 year trend of malaria surveillance data in the North Shewa zone of the Amhara regional, Ethiopia, spanning from July 2018 to June 2023. The malaria indicator data were gathered from the zone's public health emergency management database. Malaria data from the previous 5 years was collected, compiled, processed, and analysed using Microsoft Excel 2019., Results: Among a total of 434,110 suspected cases 47,889 (11.03%) cases were confirmed as malaria, with an average annual malaria incidence rate of 4.4 per 1000 population in the Zone. Malaria cases exhibited an increase from Epidemiological Week (Epi week) 37 to Epi week 49 (September to November) and again from Epi week 22 to week 30 (May to July). Individuals aged 15 and above, and all districts in the Zone except Angolela were notably affected by malaria., Conclusion: Despite implementing various measures to reduce malaria incidence, the disease continues to persist in the zone. Therefore, the Zone Health Department should intensify its preventive and control efforts., (© 2024. The Author(s).)

Background: Pregnant women and recent mothers face a higher risk of severe illness from Coronavirus disease 2019 due to physiological and immunological shifts during pregnancy, rendering them more vulnerable to inflammatory lung conditions. This susceptibility poses serious threats to both maternal and newborn health. Therefore, it is imperative for pregnant women to be fully informed about Coronavirus disease 2019 and to implement preventive measures. This study aimed to evaluate the collective knowledge, attitudes, and practices related to Coronavirus disease 2019 among pregnant women across Africa., Methods: The researchers collected studies from multiple databases, including Pub Med/MEDLINE, EMBASE, CINAHL, Science Direct, Scopus, Web of Science, Cochran library, and Google Scholar. A combination of search terms and Boolean operators were utilized to gather relevant literature. Each study underwent quality assessment by five authors independently, using the modified Newcastle Ottawa Scale tailored for cross-sectional research. Statistical analysis was conducted using STATA™ Version 11 software, and meta-analysis was performed using the random-effects (Der Simonian and Laird) method. Heterogeneity was evaluated using I-squared (I 2 ) statistics, and a one-out sensitivity analysis was carried out., Results: This systematic review and meta-analysis included 19 articles, involving a total of 7852 participants. It revealed that the combined estimated prevalence of good knowledge about Coronavirus disease 2019, positive attitudes, and good practices among pregnant women was found to be 61.8 % (95 % CI: 53.0%-70.65 %; I 2  = 98.7 %), 51.7 % (95 % CI: 30.34%-73.6 %; I 2  = 99.3 %), and 52.31 % (95 % CI: 41.48%-63.15 %; I 2  = 98.8 %) respectively., Conclusion: This study emphasizes a significant concern: pregnant women exhibit a notable lack of knowledge, positive attitudes, and preventive practices regarding Coronavirus disease 2019. Considering their heightened vulnerability, urgent action is required to improve their understanding, attitudes, and behaviours related to the virus. Healthcare professionals should take proactive measures to educate pregnant women, addressing this crucial gap through various strategies., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Low vaccine acceptance remains a public health threat, which is still common among healthcare workers. Therefore, the purpose of this review is to determine the level of COVID-19 vaccine acceptance among healthcare professionals in Ethiopia. This review was reported using the PRISMA checklist. Eleven articles were retrieved, then extracted on Excel, and exported to STATA version 11 software for meta-analysis. The pooled prevalence of vaccine acceptance and it is 95% CI were presented using forest plots. Tests to check heterogeneity and publication bias were done. The estimated pooled prevalence of COVID-19 vaccine acceptance among healthcare professionals in Ethiopia with a random-effects model was 54.59% (95% CI: 42.49, 66.69) through a heterogeneity index (I 2 ) of 99.1% ( p  < .001), which is relatively low. Therefore, it is important to identify and remove any myths or obstacles preventing healthcare professionals from accepting the COVID-19 vaccination.

This data article is a result of research conducted by a multidisciplinary team of researchers with the aim of analyzing agroecological transition and performance of agroecology in Ethiopia. It was conducted in four districts of Oromia and Southern Nations, Nationalities and People's (SNNP) regional states - Fedis district (East Hararghe Zone) and Miesso district (West Hararghe Zone) from the Oromia region, and Kindo Koysha district (Wolaita Zone) and Meskan district (Gurage Zone) of SNNP region. The rationale behind generating this dataset lies on the fact that there is scanty empirical evidence on the multidimensional performance of agroecology in the country. Available evidence only provides data on limited indicators of sustainability. Hence, there is a lack of comprehensive data on the economic, environmental and social indicators of sustainability and agroecological transition in the context of smallholder farming systems in the country. To fill this gap, the Food and Agriculture Organization of the United Nations (FAO) commissioned a consultancy project that employed the Tool for Agroecological Performance Evaluation (TAPE) to assess several dimensions and indicators of agroecological transitions and generate globally comparable data. A random sample of 619 farms were selected from 12 Kebeles (i.e., the lowest administrative unit), and trained enumerators gathered primary data based on a modified TAPE questionnaire using Kobo Toolbox. Participation of smallholders was on a voluntary basis and informed consent was obtained from the respondents. The survey questionnaire contained information on basic socio-economic and demographic characteristics, access to services and infrastructure, livelihood and Income-Generating Activities (IGAs), social and ecological indicators. Data on the 10 elements of agroecology was also collected. The collected data were entered into a STATA software, cleaned and analyzed through descriptive and inferential statistics. The outputs were summarized in Tables, Charts and Graphs. Since the data contained in this data article are disaggregated by study district, categories of agroecological transition, production typology and land size groups, this can foster the promotion of specific projects and programs that can address expressed needs of smallholder farmers. It can also facilitate agro-ecological based implementation of development interventions to encourage agroecological transition, sustainable development and food systems. The dataset can also enable researchers, practitioners and other decision-makers to make comparative analysis on the economic, environmental and social dimensions of sustainability. The analyzed data is provided in this data article. The raw data used to prepare figures is provided as a supplementary material. A copy of the questionnaire, raw dataset, and description of variables are available online on Mendeley Data., (© 2023 Published by Elsevier Inc.)

Pregnancies in the bicornuate uterus are usually considered high-risk because of their association with poor reproductive outcomes such as recurrent pregnancy loss, cervical insufficiency, low birthweight, preterm birth, malpresentation, cesarean delivery, and uterine rupture. The objective of the report was to show that patients with a scared bicornuate uterus at post-term could have successful pregnancy outcomes. We are presenting a 28-year-old gravida III para II lady with a bicornuate scared uterus at post-term. She has a history of early third-trimester pregnancy loss, and her second pregnancy was delivered via cesarean section. In her first pregnancy, the patient's uterus was not identified as bicornuate. However, an ultrasound during her second pregnancy revealed that she had a bicornuate uterus, which led to the diagnosis. At term, the lady had a successful cesarean section. Lastly, for the current post-term pregnancy she had no prenatal check-up. Even though this, she was coming at the latent first stage of labor and an emergency cesarean section was done.Conclusion Successful outcomes could be achieved in patients with the bicornuate uterus at post-term gestation., (© 2023. The Author(s).)

Poor quality of irrigation water and soil are among the major factors determining maize productivity in Ethiopia. This study assessed and evaluated the quality of irrigation water and soil under maize production in Soke and Woybo irrigation schemes in Boloso Sore district, Ethiopia. Four water samples per site per season were collected from the first point of the irrigation schemes and farm gate for dry and rainy seasons in 2019/2020. Soil samples of 108 were collected from 36 points, from which 18 composited samples were taken for laboratory analysis. Results show that irrigation water of the two schemes is non-saline (electrical conductivity <0.2 dS m -1 ) and in the normal pH range (6.5-7.5). Maximum concentration of cations in irrigation water was in the order of sodium (22.3 mg l -1 ) > potassium (7.3 mg l -1 ) > calcium (6.2 mg l -1 ) > magnesium (3.1 mg l -1 ). Moderate to severe sodicity (sodium adsorption ratio of 10.9) was also recorded. Sulfate, nitrate, and phosphate contents in water were trace, and increased during rainy seasons in downstream. Textural classes of soils are clay loam to clay, and less compact to restrict root penetration (bulk density ≤1.4 g cm -3 ), have slow infiltration rate (≤0.13 cm h -1 ), and medium level of total available water (≤178 mm m -1 ). Soils are strongly acidic to neutral (pH: 5-6.5), salt-free, and have low soil organic carbon (≤2.1%), low total nitrogen (≤0.1%), low available phosphorus and sulfur, and low Ca 2+ : Mg 2+ ratio. It can be concluded that the irrigation water in the study area has cation imbalance (poor quality) which affects soil quality and maize productivity. Likewise, soils of the study area have poor quality. Lime application, efficient fertilizer use, and organic matter applications can be suggested. Further study on optimizing fertilizer rates and irrigation levels has to be conducted to improve maize productivity., Competing Interests: The authors of this manuscript declare that there is no conflict of interest concerning the publication of this article., (© 2023 The Authors.)

Here, the structural, optical, and adsorptive behaviors of Ni 0.075-x Mn x Al 0.025 (OH) 2 (CO 3 ) 0.0125 ·yH 2 O (Ni-Mn/Al) layered double hydroxides (LDHs) are investigated to capture fluoride from aqueous media. The 2D mesoporous plate-like Ni-Mn/Al LDHs are successfully prepared via a co-precipitation method. The molar ratio of divalent to trivalent cations is maintained at 3:1 and the pH at 10. The X-ray diffraction (XRD) results confirm that the samples consist of pure LDH phases with a basal spacing of 7.66 to 7.72 Å, corresponding to the (003) planes at 2 θ of 11.47 o and the average crystallite sizes of 4.13 to 8.67 nm. The plate-like Mn-doped Ni-Al LDH consists of many superimposed nanosheets with a size of 9.99 nm. Energy-dispersive X-ray and X-ray photoelectron spectroscopies confirm the incorporation of Mn 2+ into the Ni-Al LDH. UV-vis diffuse reflectance spectroscopy results indicate that incorporating Mn 2+ into LDH enhances its interaction with light. The experimental data from the batch fluoride adsorption studies are subjected to kinetic models such as pseudo-first order and pseudo-second order. The kinetics of fluoride retention on Ni-Mn/Al LDH obey the pseudo-second-order model. The Temkin equation well describes the equilibrium adsorption of fluoride. The results from the thermodynamic studies also indicate that fluoride adsorption is exothermic and spontaneous., Competing Interests: The authors declare no conflict of interest., (© 2023 The Authors. Global Challenges published by Wiley‐VCH GmbH.)

Objectives: Preconception care can have a major public health impact by reducing maternal and childhood mortality and morbidity. Despite this importance, preconception care is still not implemented in majority of developing countries. Therefore, this study aimed to assess the proportion of knowledge of preconception care and its associated factors among reproductive-age women in Debre Berhan Town, Ethiopia., Design and Methods: A community-based, cross-sectional study was employed from 1 March to 30 March 2019 among reproductive-age women. Data were collected via a face-to-face, interviewer-administered questionnaire. Data were entered into EpiData V.4.6 and exported to SPSS V.25 for analysis. In a multivariable logistic regression analysis, variables with p<0.05 were declared statistically significant. The strength of statistical association was measured using adjusted OR (AOR) and 95% CI., Setting and Participants: The study was conducted in Debre Berhan Town, Ethiopia. A total of 414 reproductive-age women were enrolled in the study., Outcome: Knowledge of preconception (good or poor)., Results: Of the total 414 participants, 71 (17.1%) had good knowledge about preconception care. Women's occupation (AOR: 8.68, 95% CI 1.25 to 60.3), monthly income (AOR: 9.89, 95% CI 1.93 to 50.76), gravidity (AOR: 0.28, 95% CI 0.14 to 0.58), contraceptive use (AOR: 4.95, 95% CI 1.09 to 22.39), history of congenital abnormality (AOR: 7.53, 95% CI 2.03 to 27.96), history of neonatal death (AOR: 6.51, 95% CI 1.62 to 26.18) and time to reach a health facility (AOR: 0.37, 95% CI 0.17 to 0.79) were statistically associated with knowledge about preconception care., Conclusions: In this study area, only less than one-fifth of reproductive-age women had good knowledge of preconception care. Therefore, to improve women's knowledge about preconception care, a strong collaborative effort including several sectors should be made., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Objective: This study aimed to assess the prevalence of immediate postpartum family planning utilisation and the associated factors among postpartum women at public hospitals of North Shoa Zone, Ethiopia., Design and Methods: A facility-based cross-sectional study was conducted in 1-30 May 2020. Systematic random sampling technique was used to select the participants. Data were collected through a face-to-face interview using a structured and pretested questionnaire. Univariate and multivariable logistic regression analyses were employed. In multivariable logistic regression analysis, p<0.05 and adjusted OR (AOR) with 95% CI were used to declare statistically significant factors., Setting and Participants: The study was conducted at public hospitals of North Shoa Zone, Ethiopia. A total of 394 postpartum women within 48 hours after giving birth before discharge from the selected hospitals were enrolled in the study., Outcome: Immediate postpartum family planning utilisation (used or not used)., Results: Of the total 394 participants, 84 (21.3%) used immediate postpartum family planning. The factors associated with immediate postpartum family planning utilisation were women's age (30-34 years) (AOR: 0.118; 95% CI 0.023 to 0.616), planning status of pregnancy (AOR: 3.175; 95% CI 1.063 to 9.484), reproductive intention (AOR: 5.046; 95% CI 1.545 to 16.479), partner support (AOR: 4.293; 95% CI 1.181 to 15.61), attitude towards family planning (AOR: 2.908; 95% CI 1.081 to 7.824) and maternal satisfaction with intrapartum care (AOR: 6.243; 95% CI 2.166 to 17.994)., Conclusion: In the study area, only less than a quarter of postpartum women used immediate postpartum family planning. Therefore, enhancing immediate postpartum family planning utilisation, strengthening community awareness to develop a favourable attitude towards family planning, promoting partner involvement in family planning and ensuring maternal satisfaction during intrapartum care are essential., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2022. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Maternal satisfaction is an essential indicator of the quality and the efficiency of the health care systems. At a time when efforts are being made globally to reduce maternal and neonatal mortality and morbidity, assessing maternal satisfaction is essential. There is a dearth of studies on maternal satisfaction with intrapartum care, particularly in the study area. This study aimed to assess maternal satisfaction with intrapartum care and associated factors among postpartum women at public hospitals of North Shoa Zone Ethiopia., Methods: A facility-based cross-sectional study with a systematic random sampling technique was conducted from May1-30/ 2020. Data were entered into EpiData version 4.6 and analyzed using a statistical package for the social sciences version 25. Bivariate and multivariable logistic regression were employed. In multivariable logistic regression analysis, level of statistical significance was declared at variables with p < 0.05 and the strength of the association was measured by an adjusted odds ratio and 95% confidence interval., Result: Of the total 394 participants, 111 (28.2%) [95% CI: 23.9, 32.5] of postpartum women were satisfied with the intrapartum care. Place of residence [AOR: 1.934; 95% CI (1.183, 3.162)], planned status of the pregnancy [AOR: 2.245; 95% CI, (1.212, 4.158)], number of antenatal care visit [AOR: 2.389; 95% (1.437, 3.974)] and duration of labour [AOR: 2.463; 95% (1.378, 4.402)] were factors significantly associated with maternal satisfaction with intrapartum care., Conclusion: The proportion of maternal satisfaction with intrapartum care was low. Therefore, designing strategies to enhance maternal satisfaction by strengthening adherence to antenatal care visits, provision of family planning to prevent unplanned pregnancy, and strict utilization of partograph to prevent prolonged labour and childbirth-related complications are crucial., Competing Interests: he authors have declared that no competing interests exist.

Background: As the studies show, in every minute in the world, 380 women become pregnant and 190 face unplanned or unwanted pregnancies; 110 experience pregnancy-related complications, and one woman dies from a pregnancy-related cause. Preconception care is one of the proven strategies for the reduction in mortality and decreases the risk of adverse health effects for the woman, fetus, and neonate by optimizing maternal health services and improves woman's health. Therefore, this study aimed to estimate the pooled prevalence of utilization of preconception of care and associated factors in Africa., Methods: Systematic search of published studies done on PubMed, EMBASE, MEDLINE, Cochrane, Scopus, Web of Science CINAHL, and manually on Google Scholar. This meta-analysis follows the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The quality of studies was assessed by the modified Newcastle-Ottawa Scale (NOS). Meta-analysis was carried out using a random-effects method using the STATA™ Version 14 software., Result: From 249,301 obtained studies, 28 studies from 3 African regions involving 13067 women included in this Meta-analysis. The overall pooled prevalence of utilization of preconception care among pregnant women in Africa was found to be 18.72% (95% CI: 14.44, 23.00). Knowledge of preconception care (P = <0.001), preexisting medical condition (P = 0.045), and pregnancy intention (P = 0.016) were significantly associated with the utilization of preconception care., Conclusion: The results of this meta-analysis indicated, as one of best approaches to improve birth outcomes, the utilization of preconception care is significantly low among mothers in Africa. Therefore, health care organizations should work on strategies to improve preconception care utilization., Competing Interests: All authors declared they had no competing interests.

This study assessed the perceived causes, indicators and impacts of climate change by disaggregating farmers in to adaptor and non-adaptor groups in Goat based agro-pastoral livelihood zone of Ethiopia. The collected quantitative and qualitative data were analysed in descriptive statistics, linear regression, anomaly index, Likert rating scale and conceptual narrations. The findings demonstrated that an increasing temperature and a decreasing rainfall trends were perceived by farmers across the study decades. Higher deforestation rate, rash natural resource exploitation, poor soil and water management rehearses and alarming population growth in descending order were identified as climate change causes. Livestock and crop yield decline, livestock/human diseases epidemics and death, as well as recurrent conflicts due to grazing land were its associated impacts. The status and nature of climate change causes, indicators and impacts were however significantly diverse within similar awareness groups. To mitigate its adverse impacts, the farmers were thus applied livestock, crop and non-agriculture related adaptation strategies. Shortage of finance and eligible household labor combined with the absence of climate related information, training and extension services were hindered farmers to take any measure to the climate change. Therefore, to encourage the farmers' responsiveness, the finding underlines the importance of supplying applicable as well as legitimate natural resource exploitation system, followed by access to climate related information, awareness rising trainings, credit and input delivery services at local and community level., Competing Interests: The authors declare no conflict of interest., (© 2021 The Author(s).)

In the following work, the vibrational spectroscopic characteristics of artepillin C are reported by means of Fourier transform infrared (FT-IR) and Raman spectroscopies, surface-enhanced Raman scattering (SERS), and coherent anti-Stokes Raman scattering (CARS) microscopy. Artepillin C is an interesting compound due to its pharmacological properties, including antitumor activity. It is found as the major component of Brazilian green propolis, a resinous mixture produced by bees to protect their hives against intruders. Vibrational spectroscopic techniques have shown a strong peak at 1599 cm -1 , assigned to C=C stretching vibrations from the aromatic ring of artepillin C. From these data, direct visualization of artepillin C could be assessed by means of CARS microscopy, showing differences in the film hydration obtained for its neutral and deprotonated states. Raman-based methods show potential to visualize the uptake and action of artepillin C in biological systems, triggering its interaction with biological systems that are needed to understand its mechanism of action.

Background: Studies in sub-Saharan Africa indicated the overall prevalence of optimal breast feeding ranged between a lowest of 17.63% in East Africa and a highest of 46.37% in West Africa. It's estimated that 823,000 deaths of children could be prevented every year through optimal breastfeeding practices. However optimal breastfeeding practices is low in most setting of Ethiopia. Therefore, this study aimed to assess optimal breastfeeding practices and associated factors in Worabe town., Method: A community-based analytical cross-sectional study was conducted from April 15th-25th, 2018. A systematic sampling technique was applied on 347 sampled mothers who had children greater than or equal to 2 years old. The data was entered into EpiData (version 3.1) and subsequently exported to SPSS Statistics (version 22) for analysis. Descriptive statistics were used for presenting summary data using tables and graph. Bivariate and multi variable logistic regression analysis to identify were used to identify associated factors. The statistical significance was declared at P<0.05., Result: Optimal breastfeeding was exhibited by 42.1% of mothers. Government employees (AOR = 8.0; 95% CI: 1.7, 36.4), families with a household income of 1,500-3,000 Ethiopian birr (AOR = 4.6; 95% CI: 1.0, 20.1), individuals knowledgeable about optimal breastfeeding practices (AOR: 5.5 95% CI: 1.6, 18.1), individuals counselled about breastfeeding practices during postnatal follow-ups (AOR = 4.940, 95% CI: 1.313, 10.195), and individuals that had a caesarean section delivery (AOR = 4.2, 95% CI: 1.2, 14.1) had a higher chance of practicing optimal breastfeeding. However, mothers who did not attend or have access to antenatal care follow-ups (AOR = 0.1, 95% CI: 0.04, 0.5) were less likely to practice optimal breastfeeding., Conclusions: Less than half of mothers breastfed their children optimally. Factors that influenced this included knowledge of optimal breastfeeding practices, total household income, the woman's occupation, access to breastfeeding counselling during postnatal care follow-ups, access to antenatal care follow-ups, and mode of delivery. It is strongly recommended that optimal breastfeeding awareness programs through health education be done in collaboration with health extension workers, and zonal health offices., Competing Interests: The authors have declared that no competing interests exist.

Cell membrane models are useful to obtain molecular-level information on the interaction of biologically-relevant molecules such as pesticides whose activity is believed to depend on its effects on the membrane. In this study, we investigated the interaction between the widely used pesticide picloram with Langmuir monolayers of binary and ternary mixtures comprising 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC), sphingomyelin (SM) and cholesterol (Chol), which could be taken as representative of ocular membranes in humans. Picloram expanded the molecular area of DOPC/SM and DOPC/SM/Chol monolayers as the pesticide penetrated the hydrophobic region of the mixtures. A clear correlation was also found between the compressibility modulus (Cs -1 ) and the presence of cholesterol in the ternary monolayer. Data from polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS) confirmed that picloram interacts with both the acyl chains and headgroups. Spectral shifts and band broadening were induced by picloram, particularly for the phosphate and choline groups, probably owing to its H-bonding ability. The effects reported here on the lipid monolayers may be evidence of the possible activity of picloram on mammalian cell membranes, which highlights the importance of strict control of the level of exposure of humans dealing with pesticides., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The molecular fingerprints of yeasts Saccharomyces cerevisiae, Dekkera bruxellensis, and Wickerhamomyces anomalus (former name Pichia anomala) have been examined using surface-enhanced Raman spectroscopy (SERS) and helium ion microscopy (HIM). The SERS spectra obtained from cell cultures (lysate and non-treated cells) distinguish between these very closely related fungal species. Highly SERS active silver nano-particles suitable for detecting complex biomolecules were fabricated using a simple synthesis route. The yeast samples mixed with aggregated Ag nanoparticles yielded highly enhanced and reproducible Raman signal owing to the high density of the hot spots at the junctions of two or more Ag nanoparticles and enabled to differentiate the three species based on their unique features (spectral fingerprint). We also collected SERS spectra of the three yeast species in beer medium to demonstrate the potential of the method for industrial application. These findings demonstrate the great potential of SERS for detection and identification of fungi species based on the biochemical compositions, even in a chemically complex sample., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Giant unilamellar vesicles (GUVs) have been one of the most extensively investigated membrane model to study cell membrane-ligand interactions. In this study, we investigated the interaction between glyphosate and picloram with GUVs made with sphingomyelin (SM), cholesterol (CHOL), and dioleoyl-sn-glycerol-3-phosphocholine (DOPC) (DOPC/SM (1:1), DOPC/CHOL/SM (1:1:1)) in a physiological environment using confocal and phase contrast microscopy. At high pesticide concentrations (70 to 90 μM), we generally found the GUVs undergoing a physical such as contouring, elongation, and eventually lose their characteristic spherical shape. In addition, to determine the comparative effect of the pesticides, control experiments were performed using GUVs made with only DOPC and DOPC/SM 1:1. The results show that, at low concentration (0.5 μM), a significant effect was observed during a 30 min incubation time. These findings also suggest that cholesterol may play a significant role in the permeability of the vesicle against the action of the pesticides, which have important biological implications on the lipid composition of the membrane., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Programmable self-assembly of nucleic acids enables the fabrication of custom, precise objects with nanoscale dimensions. These structures can be further harnessed as templates to build novel materials such as metallic nanostructures, which are widely used and explored because of their unique optical properties and their potency to serve as components of novel metamaterials. However, approaches to transfer the spatial information of DNA constructions to metal nanostructures remain a challenge. We report a DNA-assisted lithography (DALI) method that combines the structural versatility of DNA origami with conventional lithography techniques to create discrete, well-defined, and entirely metallic nanostructures with designed plasmonic properties. DALI is a parallel, high-throughput fabrication method compatible with transparent substrates, thus providing an additional advantage for optical measurements, and yields structures with a feature size of ~10 nm. We demonstrate its feasibility by producing metal nanostructures with a chiral plasmonic response and bowtie-shaped nanoantennas for surface-enhanced Raman spectroscopy. We envisage that DALI can be generalized to large substrates, which would subsequently enable scale-up production of diverse metallic nanostructures with tailored plasmonic features.

We have studied the Fourier Transform Infrared (FT-IR) and the Fourier transform Raman (FT-Raman) spectra of stanozolol and oxandrolone, and we have performed quantum chemical calculations based on the density functional theory (DFT) with a B3LYP/6-31G (d, p) level of theory. The FT-IR and FT-Raman spectra were collected in a solid phase. The consistency between the calculated and experimental FT-IR and FT-Raman data indicates that the B3LYP/6-31G (d, p) can generate reliable geometry and related properties of the title compounds. Selected experimental bands were assigned and characterized on the basis of the scaled theoretical wavenumbers by their total energy distribution. The good agreement between the experimental and theoretical spectra allowed positive assignment of the observed vibrational absorption bands. Finally, the calculation results were applied to simulate the Raman and IR spectra of the title compounds, which show agreement with the observed spectra., Competing Interests: The authors declare no conflict of interest.

A cluster randomized effectiveness trial was used to examine the effects on mental development of introducing iodized salt to children 4 to 6 years of age in Ethiopia, where there were reportedly high levels of iodine deficiency. Sixty district clusters were randomized to receive iodized salt early at their markets with assistance from regular salt distributors or later as introduced by market forces. At pre- and post-iodization, 1602 children were given cognitive/language tests (namely School Readiness, WPPSI verbal reasoning, WPPSI Matrix reasoning), and mothers were interviewed concerning demographics, nutrition and health. Children's weight, height, urine and a blood sample were taken. Analyses of covariance, adjusting for clustering and baseline levels were conducted. Urinary iodine concentrations were significantly higher at endline in the intervention children than controls though both medians were above threshold. Overall, less than 5% were anemic. There were no significant main effect differences between groups on the cognitive/language tests, but there were effect modifiers, namely mother's education, child's sex and diet. For example, the intervention group performed better on the school readiness test than controls if their mothers had attended school, but not otherwise. In conclusion, the data are consistent with negative findings from studies where children 6 to 12 years were supplemented with an iodine capsule, indicating that the benefits of iodine, in salt or capsule form, for brain development may be restricted to children under 3 years. Yet, benefits may be tied to those with more educational resources or may compensate for conditions of disadvantage., (© 2016 John Wiley & Sons Ltd.)

Development of a label-free ultrasensitive nanosensor for detection of bacteria is presented. Sensitive assay for Gram-positive bacteria was achieved via electrostatic attraction-guided plasmonic bifacial superstructure/bacteria/columnar array assembled in one step. Dynamic optical hotspots were formed in the hybridized nanoassembly under wet-dry critical state amplifying efficiently the weak vibrational modes of three representative food-borne Gram-positive bacteria, that is, Staphylococcus xylosus, Listeria monocytogenes, and Enterococcus faecium. These three bacteria with highly analogous Raman spectra can be effectively differentiated through droplet wet-dry critical SERS approach combined with 3D PCA statistical analysis so that highly sensitive discrimination of bacterial species and samples containing mixtures of bacteria can be achieved.

The clinical application of a new, widely applicable method known as Karyomapping to carry out a total of 55 clinical cases of preimplantation genetic diagnosis (PGD) for single gene disorders is reported. Conventional polymerase chain reaction (PCR) testing was carried out in parallel to the new method for all cases. Clinical application of Karyomapping in this study resulted in three live births and nine clinical pregnancies out of 20 cases with a transfer. All in all, results presented in this study indicate that Karyomapping is a highly efficient, accurate and robust method for PGD of single gene disorders. Karyomapping can offer a more comprehensive assessment of the region of interest than conventional PCR analysis, allowing for more embryos to receive diagnosis (99.6% versus 96.8%), whereas its wide applicability reduces substantially the time that patients have to wait before starting their in vitro fertilization (IVF) cycle. Nonetheless, inclusion of elements of conventional PCR methodology, such as direct mutation detection, may be required in cases in which the gene of interest is in a region with reduced single nucleotide polymorphism (SNP) coverage (e.g. telomeric regions), when offering PGD for consanguineous couples, or in cases where no samples from additional family members are available., (Copyright © 2015 Reproductive Healthcare Ltd. Published by Elsevier Ltd. All rights reserved.)

Theoretical and experimental bands have been assigned to the Fourier Transform Infrared (FT-IR) and FT-Raman spectra of the bis(diethyldithiocarbamate)Cd(II) complex, abbreviated as ([Cd(DDTC)2]). The calculations and spectral interpretation have been based on the DFT/B3LYP method, infrared and Raman second derivative spectra, and band deconvolution analysis to assist in the assignment of observed fundamentals. This study validated the unusual pseudo tetrahedral molecular structure formed around the Cd(II) cation. Surface-enhanced Raman scattering (SERS) was used to determine the interactions of the normal-modes of the diethyldithiocarbamate cadmium (II) complex on nano-structured silver surfaces. Natural bond orbital (NBO) analysis was also carried out to study the Cd(II) hybridization causing the pseudo tetrahedral geometry of the framework of the [Cd(DDTC)2] complex, and to confirm the charge transfer mechanisms through second order perturbation theory analysis of the Fox Matrix. In order to find out the electronic dispersion of the Mulliken atomic charges (MAC) in the normal modes, we calculated the MAC for each normal mode and correlated these values with the SERS effect. Experimental UV-Vis spectra were obtained and charge transfer bands were assigned. Good agreement between the calculated and experimental values for the vibrational and UV-Vis spectra was obtained., (Copyright © 2015 Elsevier B.V. All rights reserved.)

We investigate if the functionality of spin crossover molecules is preserved when they are assembled into an interfacial device structure. Specifically, we prepare and investigate gold nanoparticle arrays, into which room-temperature spin crossover molecules are introduced, more precisely, [Fe(AcS-BPP)2](ClO4)2, where AcS-BPP = (S)-(4-{[2,6-(dipyrazol-1-yl)pyrid-4-yl]ethynyl}phenyl)ethanethioate (in short, Fe(S-BPP)2). We combine three complementary experiments to characterize the molecule-nanoparticle structure in detail. Temperature-dependent Raman measurements provide direct evidence for a (partial) spin transition in the Fe(S-BPP)2-based arrays. This transition is qualitatively confirmed by magnetization measurements. Finally, charge transport measurements on the Fe(S-BPP)2-gold nanoparticle devices reveal a minimum in device resistance versus temperature, R(T), curves around 260-290 K. This is in contrast to similar networks containing passive molecules only that show monotonically decreasing R(T) characteristics. Backed by density functional theory calculations on single molecular conductance values for both spin states, we propose to relate the resistance minimum in R(T) to a spin transition under the hypothesis that (1) the molecular resistance of the high spin state is larger than that of the low spin state and (2) transport in the array is governed by a percolation model.

We prepare and investigate two-dimensional (2D) single-layer arrays and multilayered networks of gold nanoparticles derivatized with conjugated hetero-aromatic molecules, i.e., S-(4-{[2,6-bipyrazol-1-yl)pyrid-4-yl]ethynyl}phenyl)thiolate (herein S-BPP), as capping ligands. These structures are fabricated by a combination of self-assembly and microcontact printing techniques, and are characterized by electron microscopy, UV-visible spectroscopy and Raman spectroscopy. Selective binding of the S-BPP molecules to the gold nanoparticles through Au-S bonds is found, with no evidence for the formation of N-Au bonds between the pyridine or pyrazole groups of BPP and the gold surface. Subtle, but significant shifts with temperature of specific Raman S-BPP modes are also observed. We attribute these to dynamic changes in the orientation and/or increased mobility of the molecules on the gold nanoparticle facets. As for their conductance, the temperature-dependence for S-BPP networks differs significantly from standard alkanethiol-capped networks, especially above 220 K. Relating the latter two observations, we propose that dynamic changes in the molecular layers effectively lower the molecular tunnel barrier for BPP-based arrays at higher temperatures.

Introduction: Mesoamerican nephropathy, also known as chronic kidney disease of unknown etiology, is widespread in Pacific coastal Central America. The cause of the epidemic is unknown, but the disease may be linked to multiple factors, including diet as well as environmental and occupational exposures. As many as 50% of men in some communities have Mesoamerican nephropathy., Objective: Describe prevalence of reduced glomerular filtration rate in a region of Nicaragua suspected to harbor high rates of Mesoamerican nephropathy; and investigate potential risk factors for such reduction associated with agricultural work (such as pesticide exposure and specific agricultural tasks associated with increased heat stress); sugar consumption; and traditional factors such as age, sex, diabetes, hypertension and nephrotoxic medication use., Methods: This study uses a cross-sectional design with nested case-control analysis. Cases were individuals with estimated glomerular filtration rates of <60mL/min/1.73m2 and controls were individuals with those >90mL/min/1.73m2, estimated using serum creatinine. Data on nutrition, past medical history, medication and substance use, and agricultural behaviors and exposures were collected using medical questionnaires from June through August, 2012. Venous blood and urine samples were collected to assess hemoglobin A1c, and dipstick proteinuria, respectively; anthropometry and blood pressure measurements were made using standard techniques. Analyses were conducted using chi square, and univariate and multiple logistic regression., Results: Of 424 individuals in the study, 151 had an occupational history in agriculture. Prevalence of glomerular filtration rate <60mL/min/1.73m2 was 9.8% among women and 41.9% among men (male to female ratio = 4.3, p<0.0001). Proteinuria =300 mg/dL was observed in <10% of participants with decreased glomerular filtration rate. Hemoglobin A1c and use of NSAIDs were not associated with decreased glomerular filtration rate. Although systolic and diastolic blood pressure was higher among participants with decreased glomerular filtration rate (p <0.001), hypertension was uncommon. Significant agricultural risk factors for reduced glomerular filtration rate included increased lifetime days cutting sugarcane during the dry season (OR 5.86, 95% CI 2.45-14.01), nondeliberate pesticide inhalation (OR 3.31, 95% CI 1.32-8.31), and sugarcane chewing (OR 3.24, 95% CI 1.39-7.58)., Conclusions: Our findings demonstrate a high prevalence of chronic kidney disease not linked to traditional risk factors, and suggest it may be associated instead with occupational exposure to heat stress in conjunction with pesticide inhalation, sugarcane chewing and sugar intake during the workday.

Background: Cutaneous leishmaniasis is endemic to many parts of the world and has re-emerged in a number of endemic countries in recent years. Environmental changes, immune status of the host and treatment failure are the three most important risk factors associated with the re-emerging and spread of Leishmaniasis. Cutaneous leishmaniasis (CL) ranges from localized, self-healing type to the disfiguring mucocutaneous and diffuse cutaneous type., Objective: To access the trend of CL patient flow in ALERT Hospital, Addis Ababa, Ethiopia., Methods: Patients' clinical and laboratory records were collected retrospectively for 1651 leishmaniasis suspected individuals from ALERT Hospital, from January 1, 2007 to December 30, 2010., Results: From the suspected individuals, 234 cases were positive for Leishmania species with Giemsa stain and/or histopathology and confirmed for CL, of whom 30 (12.8%) were diagnosed in 2007, 29 (12.4%) in 2008, 75 (32.1%) in 2009, and 100 (42.7%) were in 2010., Conclusions and Recommendations: The overall proportion of cases with leishmaniasis among the suspected cases was 234/1651 (14.2%). The distribution of CL reports was higher for patients coming from Addis Ababa surrounding areas and Oromia region, 96/234 (41.03%) and 71/234 (30.34%), respectively. In general, the trend of leishmaniasis in and around Addis Ababa seems to be increasing, which calls for further detailed epidemiological studies, including vector and reservoir host studies, to help in the prevention and control of the disease.

Surface enhancement Raman scattering (SERS) of two tautomer of thiobarbituric acid was obtained using silver and gold nanoparticles. Large band enhancement in the region of the ν(C=S), ν(C=C), δ(CH2), and δ(CNH) vibrational modes was found. Natural bond analysis of the tautomer species revealed expressive values of charge transfer, principally from lone pair electron orbitals of the S, N, and O atoms. Complete vibrational assignment was done for the two tautomers using the B3LYP/6-311+G (d, p) procedure, band deconvolution analysis, and from a rigorous interpretation of the normal modes matrix. The calculated spectra agree well with the experimental ones., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Mind the gap: A complete, cooperative spin transition for a mononuclear Mn(III) complex is reported with an 8 K hysteresis window. Raman spectra collected at a single temperature in warming and cooling modes confirm the electronic bistability within the hysteresis loop. The source of the cooperativity is a disconnection in the hydrogen-bonded 1D chains that connect adjacent cations owing to an order-disorder transition in the PF(6)(-) counterion., (Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Capillary isoelectric focusing (CIEF) with whole column imaging detection (WCID) was used to investigate drug-protein interactions. This study was designed to examine the interaction between the platinum-based anticancer drug, oxaliplatin, with human serum albumin (HSA) in aqueous solution at physiological pH with drug concentrations of 10 to 100 microM and a constant concentration of HSA (5.0 x 10(-5)M). The reaction mixtures were incubated for 0, 0.5, 1, 12, 24, 48 and 72 h at 37 degrees C in a water bath. The CIEF results indicate that with increasing the drug concentration, the complex formation of protein adducts increased compared to low-drug concentrations and major structural changes were observed as the incubation time progressed. The altered CIEF profile demonstrated the possible conformation change due to the binding of the drug. Results also showed a significant protein's pI shift for higher HSA-oxaliplatin incubation ratios. Furthermore, spectroscopic evidence shows that oxaliplatin caused the fluorescence quenching of HSA by formation of HSA-oxaliplatin complex. Using the Stern-Volmer equation, the quenching constants were calculated in the linear range. The quenching rate constants K(q) at three different temperatures indicating the presence of static quenching mechanism in the interactions of oxaliplatin with HSA. This paper describes the validity of the CIEF-WCID technique for the study of protein-drug interactions and provides useful information and insight into the interaction of anticancer drugs with HSA.

Sample preparation is often necessary to separate and concentrate various compounds prior to analysis of complex samples. In this regard, isoelectric focusing (IEF) is one of the best sample preparation methods. With this approach, however, carrier ampholytes have to be introduced into the samples, which may result in matrix interferences. In this paper, a simple ampholyte-free IEF free-flow electrophoresis design was developed for the separation of proteins. beta-Lactoglobulin, hemoglobin, myoglobin and cytochrome c were selected as model analytes. The experimental design took advantage of the electrolysis-driven production of H(+) and OH(-) ions that migrated from the anode and cathode, respectively, establishing a pH gradient spanning from 2.3 to 8.9. The separation chamber was filled with silanized glass beads as a support medium. Dialysis membranes were mounted at the two sides of the separation chamber (made of glass slides) and sealed with 2% agarose gel. The separated proteins drained from the outlets of the separation chamber and could be successfully collected into small glass tubes. The focusing process was visually observed and the separation was confirmed by capillary isoelectric focusing (cIEF) with pI markers.

CIEF with whole column imaging detection (WCID) was used to investigate the interaction of platinum-based anticancer drugs, cis-platinum(II) diamine dichloride (cisplatin) and [SP-4-2-{1R-trans)]-(1,2-cyclohexanediamine-N,N')[ethanedioata(2-)-O,O']platinum (oxaliplatin), with human hemoglobin A(0) (Hb). This technique facilitates the investigation and characterization of the formation of adducts between drugs and proteins. Cisplatin and oxaliplatin were mixed with the target protein at different concentrations (0:1, 1:1, 1:10, 1:50, and 1:100), and the reaction mixtures were incubated for 0, 0.5, 1, 12, 24, 48, and 72 h at 37 degrees C in a water-bath. The focused Hb-drug adduct profiles were imaged by WCID. At higher drug to protein molar ratios (for both oxaliplatin and cisplatin), the results exhibit significant changes in the peak shapes and heights, which may indicate the destabilization of the protein. However, the conformational change was less evident at lower molar ratios. In addition, a major pI shift was observed for the oxaliplatin reaction mixtures (for 1:10, 1:50, and 1:100 ratios). In comparison with previously reported findings obtained by other analytical methods, conclusions were drawn about the validity of CIEF as a simple and convenient method for the investigation of protein-drug interactions. These results may provide useful information for further understanding the activity and toxicity of these chemotherapeutic drugs and improving their clinical performance.

We report a patient with osseous lesions of his fingers and thumbs that eventually were proved to be a manifestation of systemic sarcoidosis. This had been mis-diagnosed as tuberculosis and the patient had previously been treated without effect with two full courses of anti-tuberculosis chemotherapy. Eventually the clinical and radiological suspicions were confirmed by biopsy.

Here, we devised a novel approach for two-dimensional (2D) protein characterization using a single one-dimensional separation followed by a second characterization in the same instrument. The approach combines capillary isoelectric focusing (CIEF), which separates proteins according to pI, with dynamic imaging detection, which permits monitoring of protein diffusion in real time and thereby allows estimation of molecular weight from diffusion coefficient. Compared with classical 2D gel electrophoresis, the approach provided several significant advantages including speed and ease in operation and automation, while yielding comparable accuracy. The approach was applicable for protein samples of low to moderate complexity.

Surface-enhanced resonance Raman scattering (SERRS) is used for single-molecule detection from spatially resolved 1-microm2 sections of a Langmuir-Blodgett (LB) monolayer deposited onto a Ag film. The target molecule, bis (benzimidazo) thioperylene (BZP), is dispersed in an arachidic acid monomolecular layer containing one BZP molecule per microm2, which is also the probing area of the Raman microscope. For concentrated samples (attomole quantities in the field of view), average SERRS, surface-enhanced fluorescence (SEF), and Raman imaging, including line mapping and global images at different temperatures, were recorded. Single-molecule SERRS spectra, obtained using an LB monolayer, present changes in bandwidth and relative intensities, highlighting the properties of single-molecule SERRS that are lost in average SERRS measurements of mixed LB monolayers obtained at the same temperatures. Also, the dilute system phenomenon of blinking is discussed with regard to results obtained from LB monolayers. The dilution process used in the single-molecule LB SERRS work is independently supported by fluorescence results obtained from very dilute solutions with monomer concentrations down to 10(-12) M.

The Langmuir-Blodgett (LB) technique has been used to obtain spatially resolved surface-enhanced resonance Raman scattering (SERRS) spectra of single dye molecules dispersed in the matrix of a fatty acid. The experimental results presented here mimic the original electrochemical surface-enhanced Raman scattering (SERS) work where the background bulk water did not interfere with the detection of the SERS signal of molecules adsorbed onto the rough silver electrode. LB monolayers of the dye in fatty acid have been fabricated on silver island films with a concentration, in average, of one probe molecule per micrometer square. The properties of single-molecule spectroscopy were investigated using micro-Raman including mapping and global images. Blinking of the SERRS signal was also observed.