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To determine molecular level changes occurring in lac resin, due to the effect of thermal stress at different levels of temperature and baking times.

Films of lac resin were applied on tin panels and baked at 100 and 200°C for different time intervals. The baked films were examined by specular reflectance spectroscopy, as they were otherwise difficult to examine through conventional IR techniques, using KBr pellet method. The results obtained were compared and correlated with work reported by earlier authors using wet chemical methods.

No significant spectroscopic change was observed on heating lac resin films at 100°C for different time intervals, as compared to air‐dried (parent) lac films. However, it was observed that when the films were baked at 200°C, the spectroscopic data indicated anhydride formation in the oligomers, due to heating effects.

Chemical researches on lac resin have been typically limited by lack of modern tools, due to the difficult and unique nature of the material. The present method to determine molecular level changes in lac due to heating effects, using state‐of‐art instrumentation and computational technique opens a new vista in this field of research.

Lac resin still has a significant place in the surface coating industry, typically in food applications, insulating vanishes, etc. The results obtained indicate that lac‐based baking compositions, when baked at 200°C, exhibit improved characteristics, in terms of adhesion, scratch hardness and even acid resistance. Such an improvement can be attributed unequivocally to the formation of anhydride linkage as evident from spectroscopic data.

As of now, there is no report of specular reflectance data on lac resin and its derivatives. This paper represents the first attempt to obtain and correlate reflectance data on lac. It also highlights the convenience of the method and the scope of sophisticated data analysis, using computational methods.

In the digital assembly system of large aircraft components (LAC), the docking trajectory of LAC is an important factor affecting the docking accuracy and stability of the LAC. The main content of docking trajectory planning is how to move the LAC from the initial posture and position to the target posture and position (TPP). This paper aims to propose a trajectory planning method of LAC based on measured data.

First, the posture and position error model of the wing is constructed according to the measured data of the measurement points (MPs) and the fork lug joints. Second, the particle swarm optimization algorithm based on the dynamic inertia factor is used to optimize the TPP of the wing. Third, to ensure the efficiency and stability of posture adjustment, the S-shaped curve is used as the motion trajectory of LAC, and the parameters of the trajectory are solved by the generalized multiplier method. Finally, a series of docking experiments are carried out.

During the process of posture adjustment, the motion of the numerical control locator (NCL) is stable, and the interaction force between the NCLs is always within a reasonable range. After the docking, the MPs are all within the tolerance range, and the coaxiality error of the fork lug hole is less than 0.2 mm.

In this paper, the measured data rather than the theoretical design model is used to solve the TPP, which improves the docking accuracy of LAC. Experiment results show that the proposed trajectory method can complete the LAC docking effectively and improve the docking accuracy.

Increased outsourcing and importation of drugs from different parts of the world to the Latin America and the Caribbean (LAC) region result in the proliferation of substandard and fake medicines, posing a threat to public health. The presence of substandard and fake medications in LAC regions is a source of public health concern and causes an economic burden to the governments in these regions. Whereas testing and detecting medication quality can easily be achieved in developed countries, the situation is different in developing countries such as LAC. This paper aims to examine the public health challenges faced by LAC regarding substandard, fake and counterfeit medicines and how the region can tackle these challenges.

Databases such as Scopus, PubMed, ScienceDirect, Embase, HINARI, EBSCOhost, Google Scholar, unpublished data, conference abstracts and papers from World Health Organization, Pan-American Health Organization and electronic newspapers were searched concerning medicine quality and in LAC.

Drug treatment improves the quality of life while decreasing morbidity and mortality among diseased populations. Absence of or inadequate testing laboratories, old and ineffective legislature, lack of enforcement or willpower and lack of effective surveillance are challenges in LAC for the proliferation of substandard and falsified medicines (SFMs).

The most significant limitation of this study was the need for the reviewers to have used articles written in other languages besides English. The LAC region has a large population in non-English-speaking countries, and many articles are written using local languages. Hence, excluding those articles is a limitation worthy of note in this review. The articles accessed needed to provide adequate information on SFM markets and illegal pharmacies or hospitals but did not. Future reviews may focus on providing illegal substandard and falsified medicines markets in the region and how they can be minimized or eliminated.

This review highlights the challenges faced by LAC countries regarding substandard, fake and counterfeit medicines. The sources, prevalence and consequences of substandard and falsified drugs were identified to suggest the measures needed to curb the infiltration of low-quality medicines in LAC.

Looked after children (LAC) are criminalised at five times the rate of children in the general population. Children in contact with both child welfare and child justice systems have higher rates of neurodisability and substance use problems, and LAC in general have high rates of school exclusion, homelessness and unemployment. This study aims to understand whether these factors persist in LAC who are in prison as adults.

Administrative data collected by the Do-IT profiler screening tool in a prison in Wales, UK, were analysed to compare sentenced prisoners who were LAC (n = 631) to sentenced prisoners who were not LAC (n = 2,201). The sample comprised all prisoners who were screened on entry to prison in a two-year period.

Prisoners who were LAC scored more poorly on a functional screener for neurodisability (effect size = 0.24), and on four self-report measures capturing traits of dyslexia (0.22), attention-deficit hyperactivity disorder (0.40), autism spectrum disorders (0.34) and developmental co-ordination disorder (0.33). Prisoners who were LAC were more likely to have been to a pupil referral unit (0.24), have substance use problems (0.16), be homeless or marginally housed (0.18) and be unemployed or unable to work due to disability (0.13).

This study uniquely contributes to our understanding of prisoners who were LAC as a target group for intervention and support with re-integration into the community upon release. LAC in prison as adults may require additional interventions to help with employment, housing and substance use. Education programmes in prison should screen for neurodisability, to develop strategies to support engagement.

To study the changes occurring in lac‐polyvinyl butyral (PVB) resin blends at molecular levels on baking the blends at 200°C for different intervals of time. It was also to ascertain the changes in key physico‐chemical parameters of these blends, before and after applying thermal stress on these blends.

Films of lac‐PVB blends, applied on tin panels were baked at 200°C for different time intervals. The FTIR spectra of the blends were recorded using specular reflectance spectroscopic techniques. The results obtained were compared and reported. The blends were also tested for different physico‐chemical parameters such as scratch hardness, flexibility, adhesion, acid resistance, etc.

On baking the blends of lac‐PVB resin at 200°C for different time intervals; fragmentation reaction, that is breakdown of products into small molecules, takes place in lac‐PVB blends. Side products such as acetic acid emerge on baking the blends. Probably hydrolysis of oxirane ring also takes place leading to the release of free alcoholic groups. The lac‐PVB blends do not show any improvement in scratch hardness and are also not resistant to the action of acids. The blends made by lac‐PVB resin baked at 200°C do not seem to be compatible as no improvement in any of the physico‐chemical parameters was seen.

Mixtures of solvents were tried for dissolving the PVB resin. In most of the solvent mixtures, PVB resin forms big lumps and is not soluble so there is a need for universal solvent for dissolving the PVB resin. The spectral studies on lac‐PVB blends were conducted qualitatively, although desirable, quantitative studies could not be carried out, due to the inherent difficulties in handling the resins.

The parent resins in lac‐PVB blends (baked at 200°C) do not seem to be compatible with one another as there was no improvement in any of the physico‐chemical parameters of the lac‐PVB blends. For making lac‐PVB blends, low range of baking temperature may be tried.

In literature, there is not much evidence of making lac‐PVB blends. This paper is the first one in attempting to obtain and correlate FTIR spectra of the lac‐PVB blends with physico‐chemical changes of the blends. This paper also highlights the convenience of the method and the scope of sophisticated data analysis such as derivative spectrometry.

Applies Fourier transform infrared spectroscopy (FTIR) to the study of lac resin, a complex natural resin of insect origin, and some of its derivatives. Compares the result obtained by this method with those from earlier studies that used classical methods of chemical analysis (the so‐called wet methods). Finds that FTIR has several advantages over the classical methods but, as spectroscopic assignments are still only tentative because of the complex nature of the lac resin, the FTIR data requires supplementing by other instrumental techniques such as FT‐Raman spectroscopy and solid state nuclear magnetic resonance.

Presents the details of an initiative launched in 1995 to transform an aerospace machined parts supply chain comprised of many small businesses from high cost mass production to lower cost lean production. It presents the overall conditions as they existed at the onset of the initiative, strategies and tactics that were used to bring about the desired changes, and an analysis of the business practices, cultural, and behavioural factors that contributed to successes and failures. Recommendations are given to help others in their quest to develop lean supply chains. The lessons learned are most applicable to supply chains containing a large number of small, privately held, businesses making inexpensive parts. However, many of the recommendations will also apply to supply chains containing larger publicly held companies producing more expensive parts or assemblies.

Despite gender parity in the general working population, the higher up one looks in ranks within the firm the fewer women one finds. This under-representation of women in top positions at firms is purportedly even more acute in Latin America and the Caribbean (LAC). LAC is a large and increasingly important region of the world where women are well-represented in the workforce and are comparatively better educated than men. Documenting if this resource is utilized at full potential is therefore of crucial importance. The purpose of this paper is to document the level and impact of female representation at the executive level in the region, as no systematic study exists on this topic.

The authors collect an original database of publicly listed companies to determine prevailing gender ratios among board members and executives in LAC region. The authors then estimate whether companies with women board members are more likely to appoint women executives. Finally, the authors estimate whether measures of female leadership at the firm are correlated with company performance.

The authors find that women are as under-represented in LAC as in the USA, but much less so in the Caribbean. The authors find that companies with women board members are more likely to appoint women executives in LAC. The authors find that measures of female leadership at the firm are correlated with company performance but only regarding board membership and only when the proportion of women on the board is greater than 30 percent. Again composition effects are important. Overall, the authors conclude that the LAC region exhibits empirical regularities about under-representation of women in leadership positions at the firm that are very similar to those found for high-income countries in Europe and North America.

The authors are the first and so far unique systematic study exists able to document the level and impact of female representation at the executive level in the region.

To investigate changes at molecular level in lac‐resole blends, occurring due to the effect of thermal stress at higher temperatures and different intervals of baking time.

Films of lac‐resole blends were applied on tin‐panels and baked at 200°C for different time intervals. The baked films were examined by specular reflectance spectroscopy, as they were otherwise difficult to examine through conventional IR techniques, using KBr pellet method. The results obtained were compared and reported.

When lac‐resole blends are baked at 200°C, in addition to possible chromic ring structures, esters linkages are formed between lac and resole molecules through cross linkages among different reactive sites of lac and PF resin. Blend of 70 per cent lac: 30 per cent resole, baked at 200°C for 20 min was found to be the best in terms of different physico‐chemical properties.

Lac‐synthetic resin blends are structurally complex in nature. Chemical researches on such blends have been typically limited due to lack of modern tools. The present method, to determine molecular level changes in lac‐resole blends due to heating effects, using state‐of‐the‐art instrumentation and computational techniques, opens a new field for research and industry.

Lac and its blends retain their significance in the surface coatings and food applications, in the formulation of lacquers, varnishes and in the finishing industry. This study could have significant implication for such industries from application point of view.

As of now, there is no report of specular reflectance data on lac‐synthetic resin blends. This paper represents the first attempt to obtain and correlate reflectance data on such blends. It also highlights the convenience of the method and the scope of sophisticated data analysis, including derivative spectrometry.